A Comparative Evaluation Study of Growth Conditions for Culturing the Isolates of Campylobacter spp.

Abstract

Campylobacter is one of the leading causes of foodborne travelers' diarrhea worldwide. Although a large number cases of campylobacteriosis go undiagnosed or unreported, it is considered as the second most common foodborne illness in the USA affecting over 1.3 million individuals every year. Of various Campylobacter species, C. jejuni, C. coli, and C. lari have been accounted for causing more than 99% of human infections. Thus, there is a need to have efficient isolation method to protect public health on food safety and monitoring the burden of campylobacteriosis. Nevertheless, it is a challenging task as the exposure of environmental stress during isolation process makes Campylobacter species less culturable. Sixteen Campylobacter spp. were used to evaluate the current protocols used in Campylobacter isolation. For optimal recovery, a range of growth media (Bolton, Columbia, Muller Hinton, CVA Campy and mCCDA), incubation temperatures, and additional supplements (including antibiotics) were tested. Blood agars without antibiotics were sufficient for the initial recovery. Afterward, the isolates could grow on agars without any supplements, and in some cases growth was observed in the presence of antibiotics. Incubation at 37 °C was found to be the optimal temperature for the recovery and the growth of most species. Additionally, a food adulteration study was also carried out by artificially contaminating three food matrices that included egg, milk, and infant cereal, with two isolates of C. jejuni and C. coli. Results of this study should provide the insight for culturing and isolation of Campylobacter from food and other sources.

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LncRNA-ATB: An indispensable cancer-related long noncoding RNA

Abstract

Objectives

Long non-coding RNAs (lncRNAs) are a group of non-protein-coding RNAs that are greater than 200 nucleotides in length. Increasing evidence indicates that lncRNAs, which may serve as either oncogenes or tumour suppressor genes, play a vital role in the pathophysiology of human diseases, especially in tumourigenesis and progression. Deregulation of lncRNAs impacts different cellular processes, such as proliferation, dedifferentiation, migration, invasion and anti-apoptosis. The aim of this review was to explore the molecular mechanism and clinical significance of long non-coding RNA-activated by transforming growth factor β (lncRNA-ATB) in various types of cancers.

Materials and methods

In this review, we summarize and analyze current studies concerning the biological functions and mechanisms of lncRNA-ATB in tumour development. The related studies were obtained through a systematic search of Pubmed, Web of Science, Embase and Cochrane Library.

Results

Long non-coding RNAs-ATB is a novel cancer-related lncRNA that was recently found to exhibit aberrant expression in a variety of malignancies, including hepatocellular carcinoma, colorectal cancer, gastric cancer, and lung cancer. Dysregulation of lncRNA-ATB has been shown to contribute to proliferation, migration and invasion of cancer cells. Long non-coding RNAs-ATB promotes tumourigenesis and progression mainly through competitively binding miRNAs to induce epithelial-mesenchymal transition (EMT).

Conclusions

Long non-coding RNAs-ATB likely represents a feasible cancer biomarker or therapeutic target.

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IJMS, Vol. 18, Pages 1929: Chemical Genomics Approach Leads to the Identification of Hesperadin, an Aurora B Kinase Inhibitor, as a Broad-Spectrum Influenza Antiviral

IJMS, Vol. 18, Pages 1929: Chemical Genomics Approach Leads to the Identification of Hesperadin, an Aurora B Kinase Inhibitor, as a Broad-Spectrum Influenza Antiviral

International Journal of Molecular Sciences doi: 10.3390/ijms18091929

Authors: Yanmei Hu Jiantao Zhang Rami Musharrafieh Raymond Hau Chunlong Ma Jun Wang

Influenza viruses are respiratory pathogens that are responsible for annual influenza epidemics and sporadic influenza pandemics. Oseltamivir (Tamiflu®) is currently the only FDA-approved oral drug that is available for the prevention and treatment of influenza virus infection. However, its narrow therapeutic window, coupled with the increasing incidence of drug resistance, calls for the next generation of influenza antivirals. In this study, we discovered hesperadin, an aurora B kinase inhibitor, as a broad-spectrum influenza antiviral through forward chemical genomics screening. Hesperadin inhibits multiple human clinical isolates of influenza A and B viruses with single to submicromolar efficacy, including oseltamivir-resistant strains. Mechanistic studies revealed that hesperadin inhibits the early stage of viral replication by delaying the nuclear entry of viral ribonucleoprotein complex, thereby inhibiting viral RNA transcription and translation as well as viral protein synthesis. Moreover, a combination of hesperadin with oseltamivir shows synergistic antiviral activity, therefore hesperadin can be used either alone to treat infections by oseltamivir-resistant influenza viruses or used in combination with oseltamivir to delay resistance evolution among oseltamivir-sensitive strains. In summary, the discovery of hesperadin as a broad-spectrum influenza antiviral offers an alternative to combat future influenza epidemics and pandemics.

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IJMS, Vol. 18, Pages 1927: 3D Printed, Microgroove Pattern-Driven Generation of Oriented Ligamentous Architectures

IJMS, Vol. 18, Pages 1927: 3D Printed, Microgroove Pattern-Driven Generation of Oriented Ligamentous Architectures

International Journal of Molecular Sciences doi: 10.3390/ijms18091927

Authors: Chan Park Kyoung-Hwa Kim Yong-Moo Lee William Giannobile Yang-Jo Seol

Specific orientations of regenerated ligaments are crucially required for mechanoresponsive properties and various biomechanical adaptations, which are the key interplay to support mineralized tissues. Although various 2D platforms or 3D printing systems can guide cellular activities or aligned organizations, it remains a challenge to develop ligament-guided, 3D architectures with the angular controllability for parallel, oblique or perpendicular orientations of cells required for biomechanical support of organs. Here, we show the use of scaffold design by additive manufacturing for specific topographies or angulated microgroove patterns to control cell orientations such as parallel (0°), oblique (45°) and perpendicular (90°) angulations. These results demonstrate that ligament cells displayed highly predictable and controllable orientations along microgroove patterns on 3D biopolymeric scaffolds. Our findings demonstrate that 3D printed topographical approaches can regulate spatiotemporal cell organizations that offer strong potential for adaptation to complex tissue defects to regenerate ligament-bone complexes.

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Hydrolysis conditions for antioxidant peptides derived from enzymatic hydrolysates of sandfish ( Arctoscopus japonicus )

Abstract

Sandfish (Arctoscopus japonicus) meat and roe were used as natural materials for the preparation of antioxidant peptides using enzymatic hydrolysis. Meat and roe were hydrolyzed using Alcalase 2.4 L and Collupulin MG, respectively. Optimal hydrolysis conditions were determined through the effects of pH, temperature, enzyme concentration, and hydrolysis time on the radical scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH). The optimal hydrolysis conditions for meat hydrolysate (MHA) obtained via Alcalase 2.4 L treatment were a pH of 6.0, temperature of 70 °C, enzyme concentration of 5% (w/w), and a hydrolysis time of 3 h. The optimal hydrolysis conditions for roe hydrolysate (RHC) obtained via Collupulin MG treatment were pH 9.0, 60 °C temperature, 5% (w/w) enzyme concentration, and 1 h hydrolysis time. Under the optimal conditions, the DPPH radical scavenging activities of MHA and RHC were 60.04 and 79.65%, respectively. These results provide fundamental data for the production of antioxidant peptides derived from sandfish hydrolysates.

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Enhancing the hydrolysis of corn starch using optimal amylases in a high-adjunct-ratio malt mashing process

Abstract

Incompletely degraded corn starch particles often seriously inhibit wort filtration and decrease a brewery's beer productivity. Herein, the inhibiting factors of starch hydrolysis and the application of amylases to degrade residual starch were evaluated. The results showed that resistant starch and the amylopectin of corn starch were not the inhibiting factors. Almost all residual starch left in the spent grain layer was proved to be degradable by amylases. Mesophilic α-amylase was selected through a comparison of nine amylases, which increased the wort filtration rate by 44%. However, >6% of corn starch was still left after mashing when a high ratio of corn starch to water (>1:3.5) was used in liquefaction. The low water content in liquefaction was proved to be the key inhibiting factor. Considering the existing equipment and brewing technology, the application of mesophilic α-amylases should be a simple and effective method for enhancing the hydrolysis of corn starch and accelerating the wort lautering process during a high-adjunct-ratio beer brewing process.

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Discrimination and geographical origin prediction of washed specialty Bourbon coffee from different coffee growing areas in Rwanda by using electronic nose and electronic tongue

Abstract

The study aimed at discriminating washed specialty Bourbon coffee from major coffee growing areas in Rwanda and evaluating the feasibility of using flavor to predict the geographical origin of Arabica coffees from different origins. Discrimination was achieved by performing a principal component analysis, and a discriminant factorial analysis (DFA) model was used to predict the geographical origin of coffee samples based on their intrinsic flavor. Discrimination results from both e-nose and e-tongue indicated clear grouping of coffee samples from areas within the same geographical sub-regions. A DFA model using e-nose was successful in predicting the geographical origin of coffee samples but not with e-tongue. Therefore, the study demonstrated that aroma could reliably be used to predict the geographical origin of coffee samples from different origins than their taste profile.

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Monitoring of the amphetamine-like substances in dietary supplements by LC-PDA and LC–MS/MS

Abstract

Recently, amphetamine-like substances derived from the β-phenylethylamine core structure have been detected in dietary supplements. Especially, β-methylphenylethylamine (BMPEA), an amphetamine isomer, has been found in dietary supplements labeled as containing Acacia rigidula. The U. S. Food and Drug Administration determined that BMPEA is not naturally present in food and does not meet the statutory definition of a dietary ingredient. In addition, BMPEA has been classified as a psychotropic drug in South Korea and a doping substance by the World Anti-Doping Agency. The aim of this study was to determine whether dietary supplements contained amphetamine and amphetamine-like substance, including β-phenylethylamine (β-PEA) and BMPEA using LC-PDA and LC–MS/MS. In 10 of 110 samples, illegally added compounds were detected in the following ranges; β-PEA 1.4–122.0 mg/g and BMPEA 4.7–37.6 mg/g. This study will contribute to enhancement of food safety in the South Korea.

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Pandemic Influenza A H1N1 Vaccination and Subsequent Risk of Type 1 Diabetes in Norway.

No abstract available

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Scientists Must Shape our Future as They Have Shaped our Past: Perspective of the Former US EPA Administrator.

No abstract available

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Spatial autocorrelation of Neogene-Quaternary lava along the Snake River Plain, Idaho, USA

Abstract

The sequence of eruption, spatial pattern, and spatio-temporal relationships among the Neogene-Quaternary rhyolitic and basaltic lava along the Snake River Plain (SRP) in Idaho are analyzed applying the spatial methods of global and local Moran's I, standard deviational ellipse, and Ripley's K-function. The results of the analyses by the Moran's I and K-function methods indicate a higher spatial autocorrelation, hence clustering, of rhyolitic lava compared to the more dispersed basaltic lava in each center of eruption along the SRP. The clustered nature of rhyolitic lava around each caldera either reflects the original spread and large thickness of the rhyolitic lava, or the absence of younger cover strata or lava like the distribution of rhyolite in the present caldera at the Yellowstone National Park. The standard deviational ellipses (SDEs) of the lavas indicate that younger basaltic lava that erupted from newer calderas overlapped older rhyolitic and basaltic lava as the position of the Yellowstone hotspot progressively migrated to the northeast along the SRP. The less eccentric SDEs of rhyolitic lava in each caldera probably reflect the original caldera-scale spread of viscous felsic lava, compared to the more eccentric and larger SDEs of basaltic lava which represent basalt's wider and more directed spread due to its higher fluidity and ability to flow longer distances along the trend of the SRP. The alignment of the long axes of the lava SDEs with the trend of the Eastern SRP and the trend of systematic spatial overlap of older lava by successively younger basaltic lava corroborate the previously reported migration of the centers of eruption along the ESRP as the Yellowstone hotspot migrated to the northeast.

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International tuberculosis research collaborations within Asia

Asia bears more than half the global tuberculosis (TB) burden. Economic development in the region has increased available funding for biomedical research and opportunity for collaboration. We explored the exte...

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Factors influencing the practice of exclusive breastfeeding among nursing mothers in a peri-urban district of Ghana

Exclusive breastfeeding (EBF) is one of the optimal infant and young child feeding practices. Globally,

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AmpC and extended spectrum beta-lactamases production among urinary isolates from a tertiary care hospital in Lalitpur, Nepal

Production of AmpC and extended spectrum beta-lactamases among urinary isolates has created a serious problem to the successful management of the urinary tract infection. The main purpose of this study was to ...

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Prevalence and significance of Mycoplasma genitalium in women living with HIV in Denmark

Mycoplasma genitalium (M. genitalium) is a sexually transmitted pathogen associated with urethritis, cervicitis, and pelvic inflammatory disease. Previous studies have shown a strong a...

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Successful treatment of acute renal failure secondary to complicated infective endocarditis by peritoneal dialysis: a case report

Infective endocarditis is one of the most common infections among intravenous drug addicts. Its complications can affect many systems, and these can include acute renal failure. There is a scarcity of cases in...

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Molar incisor hypomineralisation: prevalence

70 observational studies were included in this molar incisor hypomineralisation (MIH) prevalence. The overall prevalence of MIH was estimated to be 14.2%(95%CI; 12.6–15.8).

The post Molar incisor hypomineralisation: prevalence appeared first on National Elf Service.

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More fishers and fewer martens due to cumulative effects of forest management and climate change as evidenced from local knowledge

Monitoring of fur-bearing species populations is relatively rare due to their low densities. In addition to catch data, trappers' experience provides information on the ecology and status of the harvested spec...

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Toxicity, uptake, and accumulation of nano and bulk cerium oxide particles in Artemia salina

Abstract

Although the toxicological impact of metal oxide nanoparticles has been studied for the last few decades on aquatic organisms, the exact mechanism of action is still unclear. The fate, behavior, and biological activity of nanoparticles are dependent on physicochemical factors like size, shape, surface area, and stability in the medium. This study deals with the effect of nano and bulk CeO₂ particles on marine microcrustacean, Artemia salina. The primary size was found to be 15 ± 3.5 and 582 ± 50 nm for nano and bulk CeO₂ (TEM), respectively. The colloidal stability and sedimentation assays showed rapid aggregation of bulk particles in seawater. Both the sizes of CeO₂ particles inhibited the hatching rate of brine shrimp cyst. Nano CeO₂ was found to be more toxic to A. salina (48 h LC₅₀ 38.0 mg/L) when compared to bulk CeO₂ (48 h LC₅₀ 92.2 mg/L). Nano CeO₂-treated A. salina showed higher oxidative stress (ROS) than those treated with the bulk form. The reduction in the antioxidant activity indicated an increase in oxidative stress in the cells. Higher acetylcholinesterase activity (AChE) was observed upon exposure to nano and bulk CeO₂ particles. The uptake and accumulation of CeO₂ particles were increased with respect to the concentration and particle size. Thus, the above results revealed that nano CeO₂ was more lethal to A. salina as compared to bulk particles.

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Squid ink could make your dentist visits much less painful

Your dentist visits could become a pleasant pain-free experience, and it's all thanks to squids . A team of engineers from the University of California San Diego have developed an imaging method using squid ink and ultrasound to check for gum disease.

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Pupillary response to nitrous oxide administration in cataract surgery under general anesthesia

Despite recent innovations in cataract surgery, pupillary diameter is one of the most important affecting factors in outcome of this surgery. As cataract surgery is performed ideally when the pupil is sufficiently dilated, anesthesia may contribute significantly in success or failure of this operation. This study was performed to evaluate the effect of nitrous oxide on pupillary diameter in cataract surgery under general anesthesia.

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US consumers’ acceptability of soy sauce and bulgogi

Abstract

This study investigated acceptability and consumer segmentation of soy sauce and famous Korean dish, bulgogi. A total of 123 participants evaluated intensity of 18 attributes and sensory liking of 4 commercial soy sauce samples and bulgogi samples made by aforementioned soy sauces. The overall results showed that appearance liking was the only significant different attribute among soy sauce samples and there were no significant differences among bulgogi samples. Furthermore, there was little correlation between overall liking of soy sauce and bulgogi samples. However, different segments of consumer groups were found by cluster analysis. Four and five subgroups of consumers were identified on evaluation of soy sauce samples and bulgogi samples, respectively. These results demonstrated that consumers' different preference pattern. In conclusion, this study specified characteristics of commercial soy sauce perceived by consumers and consumers' acceptability toward soy sauces and bulgogi made using soy sauces.

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Extraction of caffeine and catechins using microwave-assisted and ultrasonic extraction from green tea leaves: an optimization study by the IV-optimal design

Abstract

In this research, optimal conditions for extraction of caffeine and polyphenols were established from Iranian green tea leaves. In the first step, caffeine was extracted with efficacy about 86% versed to 4.5% of EGC + EGCG. The EGCG + EGC was extracted from partially decaffeinated green tea leaves through microwave-assisted extraction (MAE) and ultrasound-assisted extraction (USE) with efficiency levels of 95 and 85%, respectively. The best results for the MAE process were obtained with 7.8 min and three number of extraction cycles and for the USE process were as followed: time 57 min, temperature 65 °C, and the number of extraction cycles 3. The total phenol content values at the best conditions of MAE and the USE processes were 125 ± 5 and 96 ± 6 mg gallic acid/g DW. The 50% inhibition (IC₅₀) on 1,1-diphenyl-2-picrylhydrazyl (DPPH) were 56 and 66 mg/g of phenol for the MAE and USE processes.

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Diagnosis of gastrogastric fistula on computed tomography: a quantitative approach

Abstract

Objective

To determine if the attenuation of contrast material in the excluded stomach compared with the gastric pouch is helpful in diagnosing gastrogastric (GG) fistula.

Materials and methods

In a retrospective study, 13 CT scans in 12 patients (age 43.2 ± 9.2, 10 females) who had undergone Roux-en-Y gastric bypass and who had oral contrast in both the gastric pouch and excluded stomach were qualitatively and quantitatively evaluated for GG fistula by two radiologists, using upper GI series (UGI) as the gold standard. Quantitative analysis was performed by computing the relative attenuation (RA) ratio (HU in excluded stomach/HU in gastric pouch). Statistical analysis was performed to determine if the RA ratio values correlated with the UGI findings of GG fistula.

Results

46.2% (6/13) of UGI studies demonstrated a GG fistula. Statistical analysis demonstrated a significant difference in RA ratio (P < 0.05) between the fistula group (1.12 ± 0.29) and the reflux group (0.56 ± 0.19). A receiver operating characteristic analysis identified an RA ratio of 0.8 that maximized sensitivity (100%), at the expense of specificity (78.6%), for diagnosing GG fistula. In contrast, the initial qualitative evaluation for GG fistula yielded a lower sensitivity (45.8%) and a higher specificity (89.2%). After taking RA ratios into account, radiologists' final conclusions achieved higher sensitivity (58.3%) and specificity (100%).

Conclusion

The relative attenuation ratio of oral contrast in the excluded stomach versus the gastric pouch can be a reliable tool in differentiating GG fistula from oral contrast reflux up the biliopancreatic limb on CT.

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Mechanisms of zinc binding to the solute binding protein AztC and transfer from the metallochaperone AztD [Molecular Biophysics]

Bacteria can acquire the essential metal zinc from extremely zinc-limited environments by using ATP-binding cassette (ABC) transporters. These transporters are critical virulence factors relying on specific and high-affinity binding of zinc by a periplasmic solute-binding protein (SBP). As such, the mechanisms of zinc binding and release among bacterial SBPs are of considerable interest as antibacterial drug targets. Zinc SBPs are characterized by a flexible loop near the high-affinity zinc-binding site. The function of this structure is not always clear, and its flexibility has thus far prevented structural characterization by X-ray crystallography. Here, we present intact structures for the zinc-specific SBP AztC from the bacterium Paracoccus denitrificans in the zinc-bound and the apo states. A comparison of these structures revealed that zinc loss prompts significant structural rearrangements mediated by the formation of a sodium-binding site in the apo structure. We further show that the AztC flexible loop has no impact on zinc-binding affinity, stoichiometry, or protein structure, yet is essential for zinc transfer from the metallochaperone AztD. We also found that three His residues in the loop appear to temporarily coordinate zinc and then convey it to the high-affinity binding site. Consistent with this, mutation of any of these residues to Ala abrogated zinc transfer from AztD. Our structural and mechanistic findings conclusively identify a role for the AztC flexible loop in zinc acquisition from the metallochaperone AztD and yield critical insights into metal binding by AztC from both solution and AztD. These proteins are highly conserved in human pathogens, making this work potentially useful to the development of novel antibiotics.

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Prediction models for the mortality risk in chronic dialysis patients: a systematic review and independent external validation study

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Deglycosylating enzymes acting on N-glycans in fungi: Insights from a genome survey

Publication date: Available online 7 September 2017
Source:Biochimica et Biophysica Acta (BBA) - General Subjects
Author(s): Georgios Tzelepis, Magnus Karlsson, Tadashi Suzuki
BackgroundN-Glycosylation, one of the most prominent post-translational modifications of proteins, is found in all domains of life, i.e. eukaryotes, bacteria and archaea, and has been shown to play a crucial role in modulating the physicochemical/physiological properties of carrier proteins. Deglycosylating enzymes that act on N-glycans are widely used in analyzing the structures/functions of N-glycans. Fungi are known to produce various deglycosylating enzymes, some of which are fungi-specific. While such enzymes likely are biologically relevant in fungal biology, their properties as well as their functions have not been explored in detail.Scope of reviewIn this review, we summarize the current knowledge of fungal deglycosylating enzymes and discuss their biological significance.Major conclusionsAs of this writing, five types of deglycosylating enzymes that act on N-glycans are known to occur in fungi; (1) the cytosolic peptide: N-glycanase (PNGase), (2) the acidic PNGase, (3) the glycoside hydrolase family (GH) 85 endo-β-N-acetylglucosaminidase (ENGase), (4) the GH18 cytosolic ENGase, and (5) the GH18 secreted ENGase. Interestingly, genome surveys indicate that the loss of cytosolic PNGase activity in certain fungi coincide with the occurrence of GH18 cytosolic ENGase, implying that the GH18 ENGase serves to replace the deglycosylation function of the cytosolic PNGase in those filamentous ascomycete fungi.General significanceOur review concludes that fungi promise to be valuable organisms for developing an understanding of the biological functions of PNGases/ENGases.



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Cancer of the esophagus and asbestos exposure

Background

Our study aimed at analyzing incidence and mortality from esophageal cancer within a cohort of workers with previous occupational asbestos exposure (ARDCo Program).

Methods

A 10-year follow-up study was conducted in the 14 515 male subjects included in this program between October 2003 and December 2005. Follow-up began when exposure stopped. Asbestos exposure was analyzed by industrial hygienists using data from a standardized questionnaire. The Cox model was used, with age as the time axis variable adjusted for smoking, time since first exposure (TSFE) and cumulative exposure index (CEI) of exposure to asbestos.

Results

We reported a significant dose-response relationship between CEI of exposure to asbestos and esophageal cancer, in both incidence (hazard ratio [HR] 1.26, 95% confidence interval [CI] 1.00-1.58), and mortality (HR 1.40, [95%CI 1.12-1.75]).

Conclusions

This large-scale study suggests the existence of a relationship between asbestos exposure and cancer of the esophagus

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Relationship between swallowing function and breathing/phonation

Clarification of the association between the swallowing function and respiratory and phonatory functions.

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Relationship between swallowing function and breathing/phonation

Clarification of the association between the swallowing function and respiratory and phonatory functions.

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Natural course of tonsillectomy pain: A prospective patient cohort study

The aim of this study was to determine the natural course of pain after tonsillectomy.

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Co-targeting c-Met and DNA double-strand breaks (DSBs): Therapeutic strategies in BRCA-mutated gastric carcinomas

Publication date: Available online 7 September 2017
Source:Biochimie
Author(s): Chrysovalantou Mihailidou, Michalis V. Karamouzis, Dimitrios Schizas, Athanasios G. Papavassiliou
Gastric cancer (GC) is a threatening malignancy characterized by heterogeneity. Current therapies use DNA damaging agents, for example, chemotherapeutic agents and ionizing radiation (IR). However, a significant portion of GC patients develops therapeutic resistance to DNA damage response (DDR) - inducing agents. An important mechanism is the stimulation of the c-MET RTK, which is a tyrosine kinase receptor and its ligand hepatocyte growth factor (HGF), which facilitates cell survival by boosting DNA damage repair pathways and via escaping cell cycle arrest. A small subgroup of GC diagnosed patients has defects in BRCA1 and BRCA2 as mediators of DNA repair proteins. BRCA1/2 related-tumors acquire resistance to chemotherapy through the DSBs (DNA double strand breaks) repair pathways. However, BRCA2-deficient cells, are vulnerable to PARP [poly (ADP-ribose) polymerase] inhibitors as the replication forks collapse and the DNA-induced damage is not reversed. Herein, we pose that taking into consideration the defective DDR machinery can trigger GC cell sensitization to therapies via inhibition of DNA repair response. Inhibition of DNA damage response axis may designate cancer cells with BRCAness (BRCA-mutant cells) more vulnerable to DNA-damaging mediators, such as c-Met inhibitors.

Graphical abstract

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Peptides derived from transcription factor EB bind to calcineurin at a similar region as the NFAT-type motif

Publication date: Available online 7 September 2017
Source:Biochimie
Author(s): Ruiwen Song, Jing Li, Jin Zhang, Lu Wang, Li Tong, Ping Wang, Huan Yang, Qun Wei, Huaibin Cai, Jing Luo
Calcineurin (CN) is involved in many physiological processes and interacts with multiple substrates. Most of the substrates contain similar motifs recognized by CN. Recent studies revealed a new CN substrate, transcription factor EB (TFEB), which is involved in autophagy. We showed that a 15-mer QSYLENPTSYHLQQS peptide from TFEB (TFEB-YLENP) bound to CN. When the TFEB-YLENP peptide was changed to YLAVP, its affinity for CN increased and it had stronger CN inhibitory activity. Molecular dynamics simulations revealed that the TFEB-YLENP peptide has the same docking sites in CN as the 15-mer DQYLAVPQHPYQWAK motif of the nuclear factor of activated T cells, cytoplasmic 1 (NFATc1-YLAVP). Moreover expression of the NFATc1-YLAVP peptide suppressed the TFEB activation in starved Hela cells. Our studies first identified a CN binding site in TFEB and compared the inhibitory capability of various peptides derived from CN substrates. The data uncovered a diversity in recognition sequences that underlies the CN signaling within the cell. Studies of CN-substrate interactions should lay the groundwork for developing selective CN peptide inhibitors that target CN-substrate interaction in vitro experiments.



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AN-7, a butyric acid prodrug, sensitizes cutaneous T-cell lymphoma cell lines to doxorubicin via inhibition of DNA double strand breaks repair

Summary

We previously found that the novel histone deacetylase inhibitor (HDACI) butyroyloxymethyl diethylphosphate (AN-7) had greater selectivity against cutaneous T-cell lymphoma (CTCL) than SAHA. AN-7 synergizes with doxorubicin (Dox), an anthracycline antibiotic that induces DNA breaks. This study aimed to elucidate the mechanism underlying the effect of AN-7 on Dox-induced double-strand DNA breaks (DSBs) in CTCL, MyLa and Hut78 cell lines. The following markers/assays were employed: comet assay; western blot of γH2AX and p-KAP1; immunofluorescence of γH2AX nuclear foci; Western blot of repair protein; quantification of DSBs-repair through homologous recombination. DSB induction by Dox was evidenced by an increase in DSB markers, and DSBs-repair, by their subsequent decrease. The addition of AN-7 slightly increased Dox induction of DSBs in MyLa cells with no effect in Hut78 cells. AN-7 inhibited the repair of Dox-induced DSBs, with a more robust effect in Hut78. Treatment with AN-7 followed by Dox reduced the expression of DSB-repair proteins, with direct interference of AN-7 with the homologous recombination repair. AN-7 sensitizes CTCL cell lines to Dox, and when combined with Dox, sustains unrepaired DSBs by suppressing repair protein expression. Our data provide a mechanistic rationale for combining AN-7 with Dox or other DSB inducers as a therapeutic modality in CTCL.

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FFAR2-FFAR3 receptor heteromerization modulates short-chain fatty acid sensing [Research]

Free fatty acid receptors (FFAR2/FFA2/GPR43 and FFAR3/FFA3/GPR41) are mammalian receptors for gut microbiota–derived short-chain fatty acids (SCFAs). These receptors are promising drug targets for obesity, colitis, colon cancer, asthma, and arthritis. Here, we demonstrate that FFAR2 and FFAR3 interact to form a heteromer in primary human monocytes and macrophages via proximity ligation assay, and during heterologous expression in HEK293 cells via bimolecular fluorescence complementation and fluorescence resonance energy transfer. The FFAR2-FFAR3 heteromer displayed enhanced cytosolic Ca²⁺ signaling (1.5-fold increase relative to homomeric FFAR2) and β-arrestin-2 recruitment (30-fold increase relative to homomeric FFAR3). The enhanced heteromer signaling was attenuated by FFAR2 antagonism (CATPB), Gαq inhibition (YM254890), or Gαi inhibition (pertussis toxin). Unlike homomeric FFAR2/3, the heteromer lacked the ability to inhibit cAMP production but gained the ability to induce p38 phosphorylation in HEK293 and inflammatory monocytes via a CATPB- and YM254890-sensitive mechanism. Our data, taken together, reveal that FFAR2 and FFAR3 may interact to form a receptor heteromer with signaling that is distinct from the parent homomers—a novel pathway for drug targeting.—Ang, Z., Xiong, D., Wu, M., Ding, J. L. FFAR2-FFAR3 receptor heteromerization modulates short-chain fatty acid sensing.

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Real-time acquisition of transendothelial electrical resistance in an all-human, in vitro, 3-dimensional, blood-brain barrier model exemplifies tight-junction integrity [Research]

The blood–brain barrier (BBB) consists of endothelial cells, astrocytes, and pericytes embedded in basal lamina (BL). Most in vitro models use nonhuman, monolayer cultures for therapeutic-delivery studies, relying on transendothelial electrical resistance (TEER) measurements without other tight-junction (TJ) formation parameters. We aimed to develop reliable, reproducible, in vitro 3-dimensional (3D) models incorporating relevant human, in vivo cell types and BL proteins. The 3D BBB models were constructed with human brain endothelial cells, human astrocytes, and human brain pericytes in mono-, co-, and tricultures. TEER was measured in 3D models using a volt/ohmmeter and cellZscope. Influence of BL proteins—laminin, fibronectin, collagen type IV, agrin, and perlecan—on adhesion and TEER was assessed using an electric cell-substrate impedance–sensing system. TJ protein expression was assessed by Western blotting (WB) and immunocytochemistry (ICC). Perlecan (10 µg/ml) evoked unreportedly high, in vitro TEER values (1200 ) and the strongest adhesion. Coculturing endothelial cells with astrocytes yielded the greatest resistance over time. ICC and WB results correlated with resistance levels, with evidence of prominent occludin expression in cocultures. BL proteins exerted differential effects on TEER, whereas astrocytes in contact yielded higher TEER values and TJ expression.—Maherally, Z., Fillmore, H. L., Tan, S. L., Tan, S. F., Jassam, S. A., Quack, F. I., Hatherell, K. E., Pilkington, G. J. Real-time acquisition of transendothelial electrical resistance in an all-human, in vitro, 3-dimensional, blood–brain barrier model exemplifies tight-junction integrity.

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Normoxic cells remotely regulate the acid-base balance of cells at the hypoxic core of connexin-coupled tumor growths [Research]

ATP fuels the removal of metabolic end-products, including H⁺ ions that profoundly modulate biological activities. Energetic resources in hypoxic tumor regions are constrained by low-yielding glycolysis, and any means of reducing the cost of acid extrusion, without compromising pH homeostasis, would therefore be advantageous for cancer cells. Some cancers express connexin channels that allow solute exchange between cells, and we propose that, via this route, normoxic cells supply hypoxic neighbors with acid-neutralizing HCO₃^– ions. This hypothesis was tested by imaging cytoplasmic pH in spheroidal tissue growths of connexin43-positive pancreatic cancer Colo357 cells during light-controlled H⁺ uncaging at the hypoxic core. Cytoplasmic acid retention at the core was halved in the presence of CO₂/HCO₃^–, but this process requires a restorative HCO₃^– flux. The effect of CO₂/HCO₃^– was ablated by connexin43 inhibition or knockdown. In connexin-decoupled spheroids, 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS), an inhibitor of HCO₃^– uptake, had no effect on cytoplasmic [H⁺] in the H⁺-uncaging region, indicating that DIDS-sensitive transport is not an adequate pH-regulatory strategy therein. With intact connexin-coupling, acid retention at the core increased upon DIDS treatment, indicating that HCO₃^– ions are taken up actively by peripheral cells and then transmitted passively to cells at the hypoxic core. Thus, the energetic burden of pH regulation is offloaded from hypoxic cells onto metabolically altruistic normoxic neighbors.—Dovmark, T. H., Hulikova, A., Niederer, S. A., Vaughan-Jones, R. D., Swietach, P. Normoxic cells remotely regulate the acid-base balance of cells at the hypoxic core of connexin-coupled tumor growths.

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Evaluation of a peer education program on student leaders’ energy balance-related behaviors

Few studies have reported energy balance-related behavior (EBRB) change for peer leaders delivering health promotion programs to younger students in secondary schools. Our study assessed the impact of the Stud...

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The phospholipase PNPLA7 functions as a lysophosphatidylcholine hydrolase and interacts with lipid droplets through its catalytic domain [Enzymology]

Mammalian patatin-like phospholipase domain containing proteins (PNPLAs) are lipid metabolizing enzymes with essential roles in energy metabolism, skin barrier development, and brain function. A detailed annotation of enzymatic activities and structure-function relationships remains an important prerequisite to understand PNPLA functions in (patho-)physiology, for example, in disorders such as neutral lipid storage disease, non-alcoholic fatty liver disease, and neurodegenerative syndromes. In this study, we characterized the structural features controlling the subcellular localization and enzymatic activity of PNPLA7, a poorly annotated phospholipase linked to insulin signaling and energy metabolism. We show that PNPLA7 is an endoplasmic reticulum (ER) transmembrane (TM) protein that specifically promotes hydrolysis of lysophosphatidylcholine (LPC) in mammalian cells. We found that TM and regulatory domains in the PNPLA7 N-terminal region cooperate to regulate ER targeting but are dispensable for substrate hydrolysis. Enzymatic activity is instead mediated by the C-terminal domain, which maintains full catalytic competence even in the absence of N-terminal regions. Upon elevated fatty acid flux the catalytic domain targets cellular lipid droplets and promotes interactions of PNPLA7 with these organelles in response to increased cAMP levels. We conclude that PNPLA7 acts as an ER-anchored LPC hydrolase that is composed of specific functional domains mediating catalytic activity, subcellular positioning, and interactions with cellular organelles. Our study provides critical structural insights into an evolutionarily conserved class of phospholipid-metabolizing enzymes.

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Kinetic signatures of myosin-5B, the motor involved in microvillus inclusion disease [Protein Structure and Folding]

Myosin-5B is a ubiquitous molecular motor that transports cargo vesicles of the endomembrane system in intracellular recycling pathways. Myosin-5B malfunction causes the congenital enteropathy microvillus inclusion disease, underlining its importance in cellular homeostasis. Here we describe the interaction of myosin-5B with F-actin, nucleotides, and the pyrazolopyrimidine compound myoVin-1. We show that single-headed myosin-5B is an intermediate duty ratio motor with a kinetic ATPase cycle that is rate-limited by the release of phosphate. The presence of a second head generates strain and gating in the myosin-5B dimer that alters the kinetic signature by reducing the actin-activated ADP release rate to become rate-limiting. This kinetic transition into a high duty ratio motor is a prerequisite for the proposed transport function of myosin-5B in cellular recycling pathways. Moreover, we show that the small molecule compound myoVin-1 inhibits the enzymatic and functional activity of myosin-5B in vitro. Partial inhibition of the actin-activated steady-state ATPase activity and sliding velocity suggests that caution should be used when probing the effect of myoVin-1 on myosin-5-dependent transport processes in cells.

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Structural features of human inositol phosphate multikinase rationalize its inositol phosphate kinase and phosphoinositide 3-kinase activities. [Signal Transduction]

Human inositol phosphate multikinase (HsIPMK) critically contributes to intracellular signaling through its inositol-1,4,5-trisphosphate (Ins(1,4,5)P3) 3-kinase and phosphatidylinositol- 4,5-bisphosphate (PtdIns(4,5)P2) 3-kinase activities. This catalytic profile is not conserved; orthologs from Arabidopsis thaliana and Saccharomyces cerevisiae are predominantly Ins(1,4,5)P3 6-kinases, and the plant enzyme cannot phosphorylate PtdIns(4,5)P2. Therefore, crystallographic analysis of the yeast and plant enzymes, without bound inositol phosphates, do not structurally rationalize HsIPMK activities. Here, we present 1.6 Å resolution crystal structures of HsIPMK in complex with either Ins(1,4,5)P3 or PtdIns(4,5)P2. The Ins(1,4,5)P3 headgroup of PtdIns(4,5)P2 binds in precisely the same orientation as free Ins(1,4,5)P3 itself, indicative of evolutionary optimization of 3- kinase activities against both substrates. We report on nucleotide binding between the separate N- and C-lobes of HsIPMK. The N-lobe exhibits a remarkable degree of conservation with protein kinase A (root mean square deviation = 1.8 Å), indicating common ancestry. We also describe structural features unique to HsIPMK. First, we observed a constrained, horseshoe-shaped substrate pocket, formed from an α-helix, a 310 helix, and a recently evolved tri-proline loop. We further found HsIPMK activities rely on a preponderance of Gln residues, in contrast to the larger Lys and Arg residues in yeast and plant orthologs. These conclusions are supported by analyzing 14 single-site HsIPMK mutants, some of which differentially affect 3-kinase and 6- kinase activities. Overall, we structurally rationalize phosphorylation of Ins(1,4,5)P3 and PtdIns(4,5)P2 by HsIPMK.

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C-Terminal Phosphorylation of NaV1.5 Impairs FGF13-Dependent Regulation of Channel Inactivation [Genomics and Proteomics]

Voltage-gated Na+ (NaV) channels are key regulators of myocardial excitability, and Ca2+/calmodulin-dependent protein kinase II (CaMKII)-dependent alterations in NaV1.5 channel inactivation are emerging as a critical determinant of arrhythmias in heart failure. However, the global native phosphorylation pattern of NaV1.5 subunits associated with these arrhythmogenic disorders, and the associated channel regulatory defects remain unknown. Here, we undertook phosphoproteomic analyses to identify and quantify in situ the phosphorylation sites in the NaV1.5 proteins purified from adult WT and failing CaMKIIδc-overexpressing (CaMKIIδc-Tg) mouse ventricles. Of 19 native NaV1.5 phosphorylation sites identified, two C-terminal phosphoserines at positions 1938 and 1989 showed increased phosphorylation in the CaMKIIδc-Tg, compared with the WT, ventricles. We then tested the hypothesis that phosphorylation at these two sites impairs Fibroblast Growth Factor 13 (FGF13)-dependent regulation of NaV1.5 channel inactivation. Whole-cell voltage-clamp analyses in HEK293 cells demonstrated that FGF13 increases NaV1.5 channel availability and decreases late Na+ current, two effects that were abrogated with NaV1.5 mutants mimicking phosphorylation at both sites. Additional co-immunoprecipitation experiments revealed that FGF13 potentiates the binding of calmodulin to NaV1.5, and that phosphomimetic mutations at both sites decrease the interaction of FGF13 and, consequently, of calmodulin with NaV1.5. Together, we have identified two novel native phosphorylation sites in the C-terminus of NaV1.5 that impair FGF13-dependent regulation of channel inactivation and may contribute to CaMKIIδc-dependent arrhythmogenic disorders in failing hearts.

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Identification of optineurin as an Interleukin-1 receptor-associated kinase 1-binding protein and its role in regulation of MyD88-dependent signaling [Immunology]

Upon stimulation of toll-like receptor (TLR) with various microbial ligands, induction of a variety of inflammatory genes is elicited by activation of a myeloid differentiation primary-response protein 88 (MyD88)-dependent signaling pathway. Interleukin-1 (IL-1) receptor-associated kinase 1 (IRAK1) plays an essential role in this pathway by activating nuclear factor κB (NF-κB) and mitogen-activated kinases (MAPK). Here, we identified optineurin (OPTN) as an IRAK1-binding protein by yeast two-hybrid screening using IRAK1 as bait. A C-terminal fragment of OPTN harboring a ubiquitin-binding domain was co-immunoprecipitated with IRAK1. In reporter analyses, overexpression of OPTN inhibited IL-1β-, IRAK1-, and LPS-induced NF-κB activation. Consistently, OPTN deficiency resulted in increased NF-κB activation in response to IL-1β/LPS-stimulation. To address the mechanisms underlying the inhibitory effect of OPTN on NF-κB signaling, we focused on tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6), which is an adaptor protein of IRAK1, and upon polyubiquitination plays a crucial role during NF-κB activation. Overexpression of OPTN prevented TRAF6 polyubiquitination. Furthermore, OPTN H486R mutant, which is unable to recruit the deubiquitinase CYLD, failed to inhibit IRAK1-induced NF-κB activation. These results suggest that the IRAK1-binding protein OPTN negatively regulates IL-1β/LPS-induced NF-κB activation by preventing polyubiquitination of TRAF6.

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The Rho ADP-ribosylating C3 exoenzyme binds cells via an Arg-Gly-Asp motif [Membrane Biology]

The Rho ADP-ribosylating C3 exoenzyme (C3bot) is a bacterial protein toxin devoid of a cell-binding or -translocation domain. Nevertheless, C3 can efficiently enter intact cells, including neurons, but the mechanism of C3 binding and uptake is not yet understood. Previously, we identified the intermediate filament vimentin as an extracellular membranous interaction partner of C3. However, uptake of C3 into cells still occurs (although reduced) in the absence of vimentin, indicating involvement of an additional host cell receptor. C3 harbors an Arg-Gly-Asp (RGD) motif, which is the major integrin-binding site, present in a variety of integrin ligands. To check whether the RGD motif of C3 is involved in binding to cells, we performed a competition assay with C3 and RGD peptide or with a monoclonal antibody binding to beta1-integrin subunit and binding assays in different cell lines, primary neurons and synaptosomes with C3-RGD mutants. Here, we report that pre-incubation of cells with GRGDNP peptide strongly reduced C3 binding to cells. Moreover, mutation of the RGD motif reduced C3 binding to intact cells and also to recombinant vimentin. Anti-integrin antibodies also lowered the C3 binding to cells. Our results indicate that the RGD motif of C3 is at least one essential C3 motif for binding to host cells and that integrin is an additional receptor for C3 besides vimentin.

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Transcriptional fidelities of human mitochondrial POLRMT, yeast mitochondrial Rpo41, and Phage T7 single-subunit RNA polymerases [RNA]

Single-subunit RNA polymerases (RNAPs) are present in phage T7 and in mitochondria of all eukaryotes. This RNAP class plays important roles in biotechnology and cellular energy production, but we know little about its fidelity and error rates. Herein, we report the error rates of three single-subunit RNAPs measured from the catalytic efficiencies of correct and all possible incorrect nucleotides. The average error rate of T7 RNAP (2×10−6), yeast mitochondrial Rpo41 (6×10−6), and human mitochondrial POLRMT (2×10−5) indicates high accuracy/fidelity of RNA synthesis resembling those of replicative DNA polymerases. All three RNAPs exhibit a distinctly high propensity for GTP misincorporation opposite dT, predicting frequent A to G errors in RNA with rates of ~10−4. The A→C, G→A, A→U, C→U, G→U, U→C, and U→G errors mostly due to pyrimidine to purine mismatches were relatively frequent (10−5 to10−6), whereas C→G, U→A, G→C, and C→A errors from purine to purine and pyrimidine to pyrimidine mismatches were rare (10−7 to10−10). POLRMT also shows a high C→A error rate on 8-oxo-dG templates (~10−4). Strikingly, POLRMT shows high mutagenic bypass rate, which is exacerbated by TEFM. The lifetime of POLRMT on terminally mismatched elongation substrate is increased in the presence of TEFM that allows POLRMT to efficiently bypass the error and continue with transcription. This investigation of nucleotide selectivity on normal and oxidatively damaged DNA by three single-subunit RNAPs provides the basic information to understand the error rates in mitochondria and, in case of T7 RNAP, to assess the quality of in vitro transcribed RNAs.

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The Tiam1 Guanine Nucleotide Exchange Factor is Auto-inhibited by its Pleckstrin Homology Coiled-Coil Extension Domain [Protein Structure and Folding]

T-cell lymphoma invasion and metastasis 1 (Tiam1) is a Dbl-family guanine nucleotide exchange factor (GEF) that specifically activates the Rho-family GTPase Rac1 in response to upstream signals, thereby regulating cellular processes including cell adhesion and migration. Tiam1 contains multiple domains, including an N-terminal Pleckstrin homology coiled-coiled extension (PHn-CC-Ex) and catalytic Dbl-homology and C-terminal Pleckstrin homology (DH-PHc) domain. Previous studies indicate that larger fragments of Tiam1, such the region encompassing the N-terminal to C-terminal Pleckstrin homology domains (PHn-PHc) are auto-inhibited. However, the domains in this region responsible for inhibition remain unknown. Here, we show that the PHn-CC-Ex domain inhibits Tiam1 GEF activity by directly interacting with the catalytic DH-PHc domain, preventing Rac1 binding and activation. Enzyme kinetics experiments suggested that Tiam1 is auto-inhibited through occlusion of the catalytic site, rather than by allostery. Small angle X-ray scattering and ensemble modeling yielded models of the PHn-PHc fragment that indicate it is in equilibrium between open and closed conformational states. Finally, single-molecule experiments support a model in which conformational sampling between the open and closed states of Tiam1 contributes to Rac1 dissociation. Our results highlight the role of the PHn-CC-Ex domain in Tiam1 GEF regulation, and suggest a combinatorial model for GEF inhibition and activation of the Rac1 signaling pathway.

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Zinc oxide nanoparticles provide anti-cholera activity by disrupting the interaction of cholera toxin with the human GM1 receptor [Molecular Bases of Disease]

Vibrio cholerae causes cholera and is the leading cause of diarrhea in the developing countries, highlighting the need for the development of new treatment strategies to combat this disease agent. While exploring the possibility of using zinc oxide (ZnO) nanoparticles (NPs) in cholera treatment, we previously found that ZnO NPs reduce fluid accumulation in mouse ileum induced by the cholera toxin (CT) protein. To uncover the mechanism of action of ZnO NPs on CT activity, here we used classical (O395) and El Tor (C6706) V. cholerae biotypes in growth and biochemical assays. We found that a ZnO NP concentration of 10 µg/ml did not affect the growth rates of these two strains, nor did we observe that ZnO NPs reduce the expression levels of CT mRNA and protein. It was observed that ZnO NPs form a complex with CT, appear to disrupt the CT secondary structure, and block its interaction with the GM1 ganglioside receptor in the outer leaflet of the plasma membrane in intestinal (HT-29) cells and thereby reduce CT uptake into the cells. In the range of 2.5-10 µg/ml, ZnO NPs exhibited no cytotoxicity on kidney (HEK293) and HT-29 cells. We conclude that ZnO NPs prevent the first step in the translocation of cholera toxin into intestinal epithelial cells without exerting measurable toxic effects on HEK293 and HT-29 cells.

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Peptide array based screening reveals a large number of proteins interacting with the ankyrin repeat domain of the zDHHC17 S-acyltransferase [Computational Biology]

zDHHC S-acyl-transferases are enzymes catalyzing protein S-acylation, a common post-translational modification on proteins frequently affecting their membrane targeting and trafficking. The ankyrin-repeat (AR) domain of zDHHC17 (HIP14) and zDHHC13 (HIP14L) S-acyltransferases, which is involved in both substrate recruitment and S-acylation-independent functions, was recently shown to bind at least six proteins, by specific recognition of a consensus sequence in them. To further refine the rules governing binding to the AR of zDHHC17, we employed peptide arrays based on zDHHC AR-binding motif (zDABM) sequences of synaptosomal-associated protein 25 (SNAP25) and cysteine string protein alpha (CSPα). Quantitative comparisons of the binding preferences of 400 peptides allowed us to construct a position-specific scoring matrix (PSSM) for zDHHC17 AR binding, with which we predicted and subsequently validated many putative zDHHC17 interactors. We identified 95 human zDABM sequences with unexpected versatility in amino-acid usage; these sequences were distributed among 90 proteins, of which 62 have not been previously implicated in zDHHC17/13 binding. These zDABM-containing proteins included all family members of the SNAP25, sprouty, cornifelin, ankyrin, and SLAIN-motif containing families; seven endogenous Gag polyproteins sharing the same binding sequence; and several proteins involved in cytoskeletal organization, cell communication, and regulation of signaling. A dozen of the zDABM-containing proteins had more than one zDABM sequence, while isoform-specific binding to the AR of zDHHC17 was identified for the Ena/VASP-like protein. The large number of zDABM sequences within the human proteome suggests that zDHHC17 may be an interaction hub regulating many cellular processes.

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Switch I-Dependent Allosteric Signaling In A G-Protein Chaperone-B12 Enzyme Complex [Enzymology]

G-proteins regulate various processes ranging from DNA replication and protein synthesis to cytoskeletal dynamics and cofactor assimilation, and serve as models for uncovering strategies deployed for allosteric signal transduction. MeaB is a multifunctional G-protein chaperone, which gates loading of the active 5'-deoxyadenosylcobalamin cofactor onto methylmalonyl-CoA mutase (MCM) and precludes loading of inactive cofactor forms. MeaB also safeguards MCM, which uses radical chemistry, against inactivation and rescues MCM inactivated during catalytic turnover by using the GTP-binding energy to offload inactive cofactor. The conserved switch I and II signaling motifs used by G-proteins, are predicted to mediate allosteric regulation in response to nucleotide binding and hydrolysis in MeaB. Herein, we targeted conserved residues in the MeaB switch I motif to interrogate the function of this loop. Unexpectedly, the switch I mutations had only modest effects on GTP binding and on GTPase activity and did not perturb stability of the MCM-MeaB complex. However, these mutations disrupted multiple MeaB chaperone functions including cofactor editing, loading and offloading. Hence, while residues in the switch I motif are not essential for catalysis they are important for allosteric regulation. Furthermore, single particle EM analysis revealed for the first time, the overall architecture of the MCM-MeaB complex, which exhibits a 2:1 stoichiometry. These EM studies also demonstrate that the complex exhibits considerable conformational flexibility. In conclusion, the switch I element does not significantly stabilize the MCM-MeaB complex or influence the affinity of MeaB for GTP, but is required for transducing signals between MeaB and MCM.

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CD155T/TIGIT Signaling Regulates CD8+ T Cell Metabolism and Promotes Tumor Progression in Human Gastric Cancer

The T cell surface molecule TIGIT is an immune checkpoint molecule that inhibits T cell responses, but its roles in cancer are little understood. In this study, we evaluated the role TIGIT checkpoint plays in the development and progression of gastric cancer (GC). We show that the percentage of CD8 T cells that are TIGIT+ was increased in GC patients compared to healthy individuals. These cells showed functional exhaustion with impaired activation, proliferation, cytokine production and metabolism, all of which were rescued by glucose. In addition, GC tissue and cell lines expressed CD155, which bound TIGIT receptors and inactivated CD8 T cells. In a T cell-GC cell co-culture system, GC cells deprived CD8 T cells of glucose and impaired CD8 T cell effector functions; these effects were neutralized by the additional glucose or by TIGIT blockade. In GC tumor cells, CD155 silencing increased T cell metabolism and IFNγ production, whereas CD155 overexpression inhibited T cell metabolism and IFNγ production; this inhibition was neutralized by TIGIT blockade. Targeting CD155/TIGIT enhanced CD8 T cell reaction and improved survival in tumor bearing mice. Combined targeting of TIGIT and PD-1 further enhanced CD8 T cell activation and improved survival in tumor bearing mice. Our results suggest that GC cells inhibit CD8 T cell metabolism through CD155/TIGIT signaling, which inhibits CD8 T cell effector functions, resulting in hyporesponsive antitumor immunity. These findings support the candidacy of CD155/TIGIT as a potential therapeutic target in gastric cancer.

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FSTL1 promotes metastasis and chemoresistance in esophageal squamous cell carcinoma through NF{kappa}B-BMP signaling crosstalk

Esophageal squamous cell carcinoma (ESCC) has a generally poor prognosis and molecular markers to improve early detection and predict outcomes are greatly needed. Here we report that the BMP-binding follistatin-like protein FSTL1 is overexpressed in ESCCs where it correlates with poor overall survival. Genetic amplification of FSTL1 or chromosome 3q where it is located occurred frequently in ESCC, where FSTL1 copy number correlated positively with higher FSTL1 protein expression. Elevating FSTL1 levels by various means was sufficient to drive ESCC cell proliferation, clonogenicity, migration, invasion, self-renewal and cisplatin resistance in vitro and tumorigenicity and distant metastasis in vivo. Conversely, FSTL1 attenution by shRNA or neutralizing antibody elicited the opposite effects in ESCC cells. mRNA profiling analyses suggested that FSTL1 drives ESCC oncogenesis and metastasis through various pathways with deregulation of NF-κB and BMP signaling figuring prominently. Crosstalk between the NF-κB and BMP pathways was evidenced by functional rescue experiments using inhibitors of NF-κB and TLR4. Our results establish the significance of FSTL1 in driving oncogenesis and metastasis in ESCC by coordinate NF-κB and BMP pathway control, with implications for its potential use as a diagnostic or prognostic biomarker and a candidate therapeutic target in this disease setting.

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Discovery of human-similar gene fusions in canine cancers

Canine cancers represent a tremendous natural resource due to their incidence and striking similarities to human cancers, sharing similar clinical and pathological features as well as oncogenic events including identical somatic mutations. Considering the importance of gene fusions as driver alterations, we explored their relevance in canine cancers. We focused on three distinct human-comparable canine cancers representing different tissues and embryonic origins. Through RNA-Seq, we discovered similar gene fusions as those found in their human counterparts: IGK-CCND3 in B-cell lymphoma, MPB-BRAF in glioma, and COL3A1-PDGFB in dermatofibrosarcoma protuberans-like. We showed not only similar partner genes but also identical breakpoints leading to oncogene overexpression. This study demonstrates similar gene fusion partners and mechanisms in human-dog corresponding tumors and allows for selection of targeted therapies in preclinical and clinical trials with pet dogs prior to human trials, within the framework of personalized medicine.

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Genetic dissociation of glycolysis and the TCA cycle affects neither normal nor neoplastic proliferation

Rapidly proliferating cells increase glycolysis at the expense of oxidative phosphorylation (oxphos) to generate sufficient levels of glycolytic intermediates for use as anabolic substrates. The pyruvate dehydrogenase complex (PDC) is a critical mitochondrial enzyme that catalyzes pyruvate's conversion to acetyl coenzyme A (AcCoA), thereby connecting these two pathways in response to complex energetic, enzymatic and metabolic cues. Here we utilized a mouse model of hepatocyte-specific PDC inactivation to determine the need for this metabolic link during normal hepatocyte regeneration and malignant transformation. In PDC "knockout" (KO) animals, the long-term regenerative potential of hepatocytes was unimpaired, and growth of aggressive experimental hepatoblastomas (HB) was only modestly slowed in the face of 80-90% reductions in AcCoA and significant alterations in the levels of key TCA cycle intermediates and amino acids. Overall, oxphos activity in KO livers and HB was comparable to that of control counterparts, with evidence that metabolic substrate abnormalities were compensated for by increased mitochondrial mass. These findings demonstrate that the biochemical link between glycolysis and the TCA cycle can be completely severed without affecting normal or neoplastic proliferation, even under the most demanding circumstances.

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KDM4 inhibition targets breast cancer stem-like cells

Traditional treatments for breast cancer fail to address therapy-resistant cancer stem-like cells that have been characterized by changes in epigenetic regulators such as the lysine demethylase KDM4. Here we describe an orally available, selective and potent KDM4 inhibitor (QC6352) with unique preclinical characteristics. To assess the anti-tumor properties of QC6352, we established a method to isolate and propagate breast cancer stem-like cells (BCSC) from individual triple-negative tumors resected from patients after neoadjuvant chemotherapy. Limiting-dilution orthotopic xenografts of these BCSC regenerated original patient tumor histology and gene expression. QC6352 blocked BCSC proliferation, sphere formation and xenograft tumor formation. QC6352 also abrogated expression of EGFR which drives the growth of therapy-resistant triple-negative breast cancer cells. Our findings validate a unique BCSC culture system for drug screening and offer preclinical proof of concept for KDM4 inhibition as a new strategy to treat triple-negative breast cancer.

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Enhanced acid sphingomyelinase activity drives immune evasion and tumor growth in non-small cell lung carcinoma

The lipid hydrolase enzyme acid sphingomyelinase (ASM) is required for the conversion of the lipid cell membrane component sphingomyelin into ceramide. In cancer cells, ASM-mediated ceramide production is important for apoptosis, cell proliferation and immune modulation, highlighting ASM as a potential multimodal therapeutic target. In this study, we demonstrate elevated ASM activity in the lung tumor environment and blood serum of patients with non-small cell lung cancer (NSCLC). RNAi-mediated attenuation of SMPD1 in human NSCLC cells rendered them resistant to serum starvation-induced apoptosis. In a murine model of lung adenocarcinoma, ASM deficiency reduced tumor development in a manner associated with significant enhancement of Th1-mediated and cytotoxic T cell-mediated antitumor immunity. Our findings indicate that targeting ASM in NSCLC can act by tumor cell intrinsic and extrinsic mechanisms to suppress tumor cell growth, most notably by enabling an effective antitumor immune response by the host.

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Transplantation of iPS-derived tumor cells with a homozygous MHC haplotype induces GRP94 antibody production in MHC-matched macaques

Immune surveillance is a critical component of the anti-tumor response in vivo, yet the specific components of the immune system involved in this regulatory response remain unclear. In this study, we demonstrate that autoantibodies can mitigate tumor growth in vitro and in vivo. We generated two cancer cell lines, embryonal carcinoma and glioblastoma cell lines, from monkey induced pluripotent stem cells (iPSC) carrying a homozygous haplotype of major histocompatibility complex (MHC, Mafa in Macaca fascicularis). To establish a monkey cancer model, we transplanted these cells into monkeys carrying the matched Mafa haplotype in one of the chromosomes. Neither Mafa-homozygous cancer cell line grew in monkeys carrying the matched Mafa haplotype heterozygously. We detected in the plasma of these monkeys an IgG autoantibody against GRP94, a heat shock protein. Injection of the plasma prevented growth of the tumor cells in immunodeficient mice, whereas plasma IgG depleted of GRP94 IgG exhibited reduced killing activity against cancer cells in vitro. These results indicate that humoral immunity, including autoantibodies against GRP94, plays a role in cancer immune surveillance.

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miR-193b-regulated signaling networks serve as tumor suppressors in liposarcoma and promote adipogenesis in adipose-derived stem cells

Well-differentiated and dedifferentiated liposarcomas (WDLS/DDLS) account for approximately 13% of all soft tissue sarcoma in adults and cause substantial morbidity or mortality in the majority of patients. In this study, we evaluated the functions of miRNA (miR-193b) in liposarcoma in vitro and in vivo. Deep RNA sequencing on 93 WDLS, 145 DDLS and 12 normal fat samples demonstrated that miR-193b was significantly underexpressed in DDLS compared to normal fat. Re-introduction of miR-193b induced apoptosis in liposarcoma cells and promoted adipogenesis in human adipose-derived stem cells (ASC). Integrative transcriptomic and proteomic analysis of miR-193b-target networks identified novel direct targets including CRK-like proto-oncogene (CRKL) and focal adhesion kinase (FAK). miR-193b was found to regulate FAK-SRC-CRKL signaling through CRKL and FAK. miR-193b also stimulated ROS signaling by targeting the antioxidant methionine sulfoxide reductase A (MSRA) to modulate liposarcoma cell survival and ASC differentiation state. Expression of miR-193b in liposarcoma cells was downregulated by promoter methylation resulting at least in part from increased expression of the DNA methyltransferase DNMT1 in WDLS/DDLS. In vivo, miR-193b mimetics and FAK inhibitor (PF-562271) each inhibited liposarcoma xenograft growth. In summary, miR-193b not only functions as a tumor suppressor in liposarcoma, but also promotes adipogenesis in ASC. Furthermore, this study reveals key tyrosine kinase and DNA methylation pathways in liposarcoma, some with immediate implications for therapeutic exploration.

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Opsin 3 and 4 Mediate Light-Induced Pulmonary Vasorelaxation that is Potentiated by G-Protein Receptor Kinase 2 Inhibition

We recently demonstrated that blue light induces vasorelaxation in the systemic mouse circulation, a phenomenon mediated by the non-visual G protein-coupled receptor (GPCR) melanopsin (opsin 4; Opn4). Here we tested the hypothesis that non-visual opsins mediate photorelaxation in the pulmonary circulation. We discovered Opsin 3 (Opn3), Opn4, and G-protein coupled receptor kinase 2 (GRK2) in rat pulmonary arteries (PAs) and in pulmonary arterial smooth muscle cells (PASMCs), where the opsins interact directly with GRK2 as demonstrated with a proximity ligation assay. Light elicited an intensity-dependent relaxation of PAs pre-constricted with phenylephrine (PE), with a maximum response between 400-460 nm (blue light). Wavelength-specific photorelaxation was attenuated in PAs from Opn4-/- mice and further reduced following shRNA-mediated knockdown of Opn3. Inhibition of GRK2 amplified the response and prevented physiologic desensitization to repeated light exposure. Blue light also prevented PE-induced constriction in isolated PAs, decreased basal tone, ablated PE-induced single-cell contraction of PASMCs, and reversed PE-induced depolarization in PASMCs when GRK2 was inhibited. The photorelaxation response was modulated by soluble guanylyl cyclase, but not by protein kinase G or nitric oxide. Most importantly, blue light induced significant vasorelaxation of PAs from rats with chronic pulmonary hypertension and effectively lowered pulmonary arterial pressure (PPA) in isolated intact perfused rat lungs subjected to acute hypoxia. These findings show that functional Opn3 and Opn4 in PAs represent an endogenous "optogenetic system" that mediates photorelaxation in the pulmonary vasculature. Phototherapy in conjunction with GRK2 inhibition could therefore provide an alternative treatment strategy for pulmonary vasoconstrictive disorders.

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Childhood tolerance of severe influenza: a mortality analysis in mice

During the 1918 influenza pandemic, children experienced substantially lower mortality than adults, a striking but unexplained finding. Whether this was due to enhanced resistance (reduced virus load) or better tolerance (reduced impact of infection) has not been defined. We found that prepubertal mice infected with H1N1 influenza virus also showed greater survival than infected pubertal mice, despite similar virus loads. Transcriptome profiling of infected lungs identified estrogen as a regulator of susceptibility in both sexes, and also linked better survival to late expression of IL-1beta. Blocking puberty with gonadectomy or a GnRH antagonist improved survival. Estrogen or testosterone (which can be converted to estrogen) restored susceptibility of gonadectomized pubertal mice to influenza mortality, but dihydrotestosterone (which cannot be converted to estrogen) did not. Estrogen receptor blockade with fulvestrant in both male and female pubertal mice resulted in improved survival, even when given three days after infection. Moreover, late, but not early, IL-1beta neutralization after infection was also protective. These findings indicate that pubertal increases in estrogen in both sexes are associated with increased mortality during influenza. This helps explain the reduced mortality of children seen with influenza in 1918, and might also be relevant to childhood tolerance to many other infectious diseases.

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The TNF Receptor Superfamily-NF-κB Axis Is Critical to Maintain Effector Regulatory T Cells in Lymphoid and Non-lymphoid Tissues

Publication date: Available online 7 September 2017
Source:Cell Reports
Author(s): Ajithkumar Vasanthakumar, Yang Liao, Peggy Teh, Maria F. Pascutti, Anna E. Oja, Alexandra L. Garnham, Renee Gloury, Jessica C. Tempany, Tom Sidwell, Eloy Cuadrado, Paul Tuijnenburg, Taco W. Kuijpers, Najoua Lalaoui, Lisa A. Mielke, Vanessa L. Bryant, Philip D. Hodgkin, John Silke, Gordon K. Smyth, Martijn A. Nolte, Wei Shi, Axel Kallies
After exiting the thymus, Foxp3⁺ regulatory T (Treg) cells undergo further differentiation in the periphery, resulting in the generation of mature, fully suppressive effector (e)Treg cells in a process dependent on TCR signaling and the transcription factor IRF4. Here, we show that tumor necrosis factor receptor superfamily (TNFRSF) signaling plays a crucial role in the development and maintenance of eTreg cells. TNFRSF signaling activated the NF-κB transcription factor RelA, which was required to maintain eTreg cells in lymphoid and non-lymphoid tissues, including RORγt⁺ Treg cells in the small intestine. In response to TNFRSF signaling, RelA regulated basic cellular processes, including cell survival and proliferation, but was dispensable for IRF4 expression or DNA binding, indicating that both pathways operated independently. Importantly, mutations in the RelA binding partner NF-κB1 compromised eTreg cells in humans, suggesting that the TNFRSF-NF-κB axis was required in a non-redundant manner to maintain eTreg cells in mice and humans.

Graphical abstract

Teaser

Effector regulatory T (eTreg) cells are potent repressors of immune pathology in lymphoid and non-lymphoid tissues. Vasanthakumar et al. have identified a signaling nexus, composed of TNFRSF and NF-κB/RelA, which operates independently of TCR-induced transcription factor IRF4 and is required for the differentiation and maintenance of eTreg cells.


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Blood monocytes sample MelanA/MART1 antigen for long-lasting cross-presentation to CD8+ T cells after differentiation into dendritic cells

Abstract

Human blood monocytes are very potent to take up antigens. Like macrophages in tissue, they efficiently degrade exogenous protein and are less efficient than dendritic cells at cross-presenting antigens to CD8⁺ T cells. Although it is generally accepted that dendritic cells take up tissue antigens and then migrate to lymph nodes to prime T cells, the mechanisms of presentation of antigens taken up by monocytes are poorly documented so far. In the present work, we show that monocytes loaded in vitro with MelanA long peptides retain the capacity to stimulate antigen-specific CD8⁺ T cell clones after 5 days of differentiation into monocytes-derived dendritic cells (MoDC). Tagged-long peptides can be visualized in electron-dense endocytic compartments distinct from lysosomes, suggesting that antigens can be protected from degradation for extended periods of time. To address the pathophysiological relevance of these findings, we screened blood monocytes from eighteen metastatic melanoma patients and found that CD14⁺ monocytes from 2 patients effectively activate a MelanA-specific CD8 T cell clone after in vitro differentiation into MoDC. This in vivo sampling of tumor antigen by circulating monocytes might alter the tumor-specific immune response and should be taken into account for cancer immunotherapy. This article is protected by copyright. All rights reserved.

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Breast conserving therapy and mastectomy revisited: Breast cancer-specific survival and the influence of prognostic factors in 129,692 patients

Abstract

This large population-based study compared breast-conserving surgery with radiation therapy (BCT) with mastectomy on (long-term) breast cancer-specific (BCSS) and overall survival (OS), and investigated the influence of several prognostic factors.

Patients with primary T1-2N0-2M0 breast cancer, diagnosed between 1999-2012, were selected from the Netherlands Cancer Registry. We investigated the 1999-2005 (long-term outcome) and the 2006-2012 cohort (contemporary adjuvant systemic therapy). Cause of death was derived from the Statistics Netherlands (CBS). Multivariable analyses, per time cohort, were performed in T1-2N0-2, and separately in T1-2N0-1 and T1-2N2 stages. The T1-2N0-1 stages were further stratified for age, hormonal receptor and HER2 status, adjuvant systemic therapy and comorbidity.

In total, 129,692 patients were included. In the 1999-2005 cohort, better BCSS and OS for BCT than mastectomy was seen in all subgroups, except in patients <40 years with T1-2N0-1 stage. In the 2006-2012 cohort, superior BCSS and OS were found for T1-2N0-1, but not for T1-2N2. Subgroup analyses for T1-2N0-1 showed superior BCSS and OS for BCT in patients >50 years, not treated with chemotherapy and with comorbidity. Both treatments led to similar BCSS in patients <50 years, without comorbidity and those treated with chemotherapy.

Although confounding by severity and residual confounding cannot be excluded, this study showed better long-term BCSS for BCT than mastectomy. Even with more contemporary diagnostics and therapies we identified several subgroups that may benefit from BCT. Our results support the hypothesis that BCT might be preferred in most breast cancer patients when both treatments are suitable. This article is protected by copyright. All rights reserved.

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Transcriptional repression of Aurora-A gene by wild-type p53 through directly binding to its promoter with histone deacetylase 1 and mSin3a

Abstract

In this study, we firstly showed that p53 transcriptionally represses Aurora-A gene expression through directly binding to its promoter. DNA affinity precipitation assay and chromatin immunoprecipitation assay indicated that p53 physically bound to the Aurora-A promoter. Moreover, the in vitro and in vivo assays showed that p53 directly bound to the Aurora-A promoter together with histone deacetylase 1 (HDAC1) and mSin3a as corepressors. Furthermore, we identified that the nucleotides -360 to -354 (CCTGCCC), upstream of the Aurora-A transcriptional start site, was responsible for the p53-mediated repression. Mutation within this site disrupted its interaction with p53, mSin3a and HDAC1, as well as attenuated the repressive effect of p53 on Aurora-A promoter activity. Treatment with trichostatin A (TSA), a HDAC1 inhibitor, disrupted the interaction of p53-HDAC1-mSin3a complex with the nucleotides -365∼-345 region, and enhanced the Aurora-A promoter activity and gene expression. Additionally, knockdown of p53 or mSin3a also drastically blocked the formation of p53-HDAC1-mSin3a repressive complex onto this promoter region and elevated the Aurora-A promoter activity and gene expression. Moreover, the p53-HDAC1-mSin3a repressive complex also involved in the inhibition of Aurora-A gene expression upon cisplatin treatment. Finally, the clinical investigation showed that Aurora-A and p53 exhibited an inverse correlation in both the expression level and prognostic status and the low p53/high Aurora-A showed the poorest prognosis of NSCLC patients. Our findings showed novel regulatory mechanisms of p53 in regulating Aurora-A gene expression in NSCLC cells.

Many types of cancer feature a boost in production of the kinase Aurora-A, and several studies have implicated the protein in transformation and tumorigenesis. Some evidence suggests that p53 affects Aurora-A expression, and in this study, the authors set out to describe that relationship. They found that p53 binds directly to the Aurora-A promoter, repressing transcription. Next, they showed that treatment with trichostatin A thwarts this repression, allowing Aurora-A transcription to proceed. Clinical investigation revealed that lung cancer patients with low p53 and high Aurora-A expression had the worst prognosis. This article is protected by copyright. All rights reserved.

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Recognition by Natural Killer cells of N6-isopentenyladenosine-treated human glioma cell lines

Abstract

Cancer cell stress induced by cytotoxic agents promote antitumor immune response. Here we observed that N6-isopentenyladenosine (iPA), an isoprenoid modified adenosine with a well established anticancer activity, was able to induce a significant upregulation of cell surface expression of NKG2D ligands on glioma cells in vitro and xenografted in vivo. Specifically suboptimal doses of iPA (0.1 and 1µM) control the selective upregulation of ULBP2 on p53wt-expressing U343MG and that of MICA/B on p53mut-expressing U251MG cells. This event made the glioblastoma cells a potent target for natural killer (NK) cell mediated recognition through a NKG2D restricted mechanism. p53 siRNA mediated knock-down and pharmacological inhibition (pifithrin-α), profoundly prevented the iPA action in restoring the immunogenicity of U343MG cells through a mechanism that is dependent upon p53 status of malignancy. Furthermore, accordingly to the preferential recognition of senescent cells by NK cells, we found that iPA treatment was critical for glioma cells entry in premature senescence through the induction of S and G2/M phase arrest.

Collectively, our results indicate that behind the well established cytotoxic and anti-angiogenic effects, iPA can also display an immune-mediated antitumor activity. The indirect engagement of the innate immune system and its additional activity in primary derived patient's glioma cell model (GBM17 and GBM37), fully increase its translational relevance and led to the exploitation of the isoprenoid pathway for a valid therapeutic intervention in anti-glioma research. This article is protected by copyright. All rights reserved.

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Combination of Functional Nanoengineering and Nanosecond Laser Texturing for Design of Superhydrophobic Aluminum Alloy with Exceptional Mechanical and Chemical Properties

ACS Nano

DOI: 10.1021/acsnano.7b04634

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Secondary Linburg-Comstock syndrome: a case report

Abstract

Linburg-Comstock syndrome is characterized by an inability to flex the interphalangeal joint of the thumb without simultaneous flexion of the distal interphalangeal joint of the index finger due to hereditary interconnections between the flexor pollicis longus (FPL) and the index flexor digitorum profundus (iFDP) resulting in discomfort and symptoms of flexor tenosynovitis. In addition to this anatomic anomaly, our clinical findings suggest that the interconnection can also result secondarily as a consequence of tenosynovial hyperplasia producing adhesions from any cause including previous surgery or trauma using the example of forearm laceration with dissection of the two tendons.

Level of Evidence: Level V, diagnostic study.

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Splice serum

Aug 6, 2016 Splice has launched a new "Rent-to-Own" plan for the Serum ... Differential regulation of serum- and glucocorticoid-inducible kinase 1 ...

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Do air-gaps behind soft body armour affect protection?

Introduction

Body armour typically comprises a fabric garment covering the torso combined with hard armour (ceramic/composite). Some users wear only soft armour which provides protection from sharp weapons and pistol ammunition. It is usually recommended that body armour is worn against the body with no air-gaps being present between the wearer and the armour. However, air-gaps can occur in certain situations such as females around the breasts, in badly fitting armour and where manufacturers have incorporated an air-gap claiming improvements in thermophysiological burden. The effect of an air-gap on the ballistic protection and the back face signature (BFS) as a result of a non-perforating ballistic impact was determined.

Methods

Armour panels representative of typical police armour (400x400 mm) were mounted on calibrated Roma Plastilina No 1 and impacted with 9 mm Luger FMJ (9x19 mm; full metal jacket; Dynamit Nobel DM11A1B2) ammunition at 365±10 m/s with a range of air-gaps (0–15 mm). Whether or not the ammunition perforated the armour was noted, the BFS was measured and the incidence of pencilling (a severe, deep and narrow BFS) was identified.

Results

For 0° impacts, a critical air-gap size of 10 mm is detrimental to armour performance for the armour/ammunition combination assessed in this work. Specifically, the incidences of pencilling were more common with a 10 mm air-gap and resulted in BFS depth:volume ratios ≥1.0. For impacts at 30° the armour was susceptible to perforation irrespective of air-gap.

Conclusions

This work suggested that an air-gap behind police body armour might result in an increased likelihood of injury. It is recommended that body armour is worn with no air-gap underneath.

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An exertional heat illness triage tool for a jungle training environment

This article introduces a practical triage tool designed to assist commanders, jungle training instructors (JTIs) and medical personnel to identify Defence Personnel (DP) with suspected exertional heat illness (EHI). The challenges of managing suspected EHI in a jungle training environment and the potential advantages to stratifying the urgency of evacuation are discussed. This tool has been designed to be an adjunct to the existing MOD mandated heat illness recognition and first aid training.

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Group O low titre only emergency donor panels for small combat teams

Introduction

Military elements increasingly operate in small teams in remote areas with no immediate blood product support. Planners and operators may endorse collection of fresh whole blood from pretested donors in emergency situations. The biggest risk of transfusion is the accidental use of ABO incompatible blood which can be fatal. The risk may be mitigated by using only group O LOw (OLO) titre donors with plasma containing low levels of the naturally occurring antibody to group A and B red cells. This paper reviews the ABO blood group distribution in potential blood donors from a high readiness UK medical regiment and explores the feasibility of using only group OLO donors in small teams.

Methods

A retrospective review of routine volunteer blood donor samples was undertaken at 6 monthly intervals during a 2-year period. Personnel were tested in groups when available during training to create multiple donor panels to simulate small teams.

Results

206 donation samples were collected from 157 potential donors. All donors were acceptable based on the lifestyle questionnaire, serology and microbiology screen. Of the 206 samples reviewed, 85 (41%) were group O (D pos and D neg). 14 group O (16.5%) were shown to have high titre of anti-A or B. Therefore, 71, that is, 34% overall were suitable as OLO donors. The donor panel size varied from 15 to 44. The absolute number of OLO donors in each panel ranged from 4 to 17 and the number of O neg donors was 0–3.

Conclusion

A third of samples were suitable as OLO donors; however, there were insufficient 'universal' donors within smaller subgroups (<10). In this situation, we recommend the careful use of both group O and group A donors or the use of a buddy-buddy blood group matrix.

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The Centre for Defence Healthcare Engagement: a focus for Defence Engagement by the Defence Medical Services

The 2015 Strategic Defence and Security Review committed the government to an ambitious programme of Defence Engagement. This paper provides a short summary of the medical contribution to UK Defence Engagement. It then describes the intentions behind the creation of the Centre for Defence Health Engagement.

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Neuropathic pain treatment and research: experiences from the United Kingdom mission to Afghanistan and future prospects

The Defence Medical Services (DMS) of the United Kingdom (UK) assumed command of the Role 3 Medical Treatment Facility field hospital during Operation HERRICK in Afghanistan from April 2006 until the final drawdown in November 2014. The signature injury sustained by coalition personnel during this period was traumatic amputation from improvised explosive devices. Many patients who had suffered extensive tissue damage experienced both nociceptive and neuropathic pain (NeuP). This presented as a heterogeneous collection of symptoms that are resistant to treatment. This paper discusses the relationship of NeuP in the context of ballistic injury, drawing in particular on clinical experience from the UK mission to Afghanistan, Operation HERRICK. The role of this paper is to describe the difficulties of assessment, treatment and research of NeuP and make recommendations for future progress within the DMS.

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Exploring the health risks of help-seeking military veterans living in different parts of the UK

Background

Little is known about the mental and physical health differences of treatment-seeking military veterans across the different nations that make up the UK. The aim of this research was to explore potential health differences in order to support better service planning.

Methods

A random cross-sectional sample of treatment-seeking veterans residing in England, Scotland, Wales and Northern Ireland was identified from a national mental health charity. 403 veterans completed a questionnaire highlighting their demographics, mental health and physical health difficulties. The data were analysed using a multinomial logistic regression with England as the baseline comparison.

Results

Help-seeking veterans residing in Northern Ireland tended to be older, have experienced less childhood adversity, joined the military after the age of 18 and took longer to seek help. Additionally, veterans from Northern Ireland had higher levels of obesity, sensory, mobility and systemic problems and a greater number of physical health conditions. Scottish and Welsh veterans had a higher risk of smoking and alcohol misuse. No differences were found in mental health presentations.

Conclusion

The findings from this paper suggest that a greater focus needs to be placed on treating physical problems in Northern Irish veterans. Alcohol misuse should be addressed in more detail in treatment programmes, particularly in Scotland and Wales. As few differences were found in the mental health presentations, this suggests that standardised services are adequate.

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Time to consider a targeted HPV vaccination programme for male military recruits

Human papillomaviruses (HPV) are the most common type of sexually transmitted infection in men but also related to high-risk cancers. This article considers the epidemiology of HPV in the male military population, the UK vaccination programme and the current UK Joint Committee on Vaccination and Immunisation recommendations. Military men may not benefit from HPV herd immunity and may have a different risk profile; vaccination may in turn reduce the operational burden of HPV-related disease within this population. Military men may benefit from a targeted vaccination programme, and the paper calls for urgent consideration of approaches that could protect them from acquiring HPV.

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Addressing the knowledge gap: sexual violence and harassment in the UK Armed Forces

Despite media interest in alleged sexual violence and harassment in the UK military, there remains a paucity of UK-based peer-reviewed research in this area. Ministry of Defence and service-specific reports support the suggestion that UK service personnel may be at risk of experiencing sexual harassment. These reports however highlight a reluctance by service personnel to report sexual harassment through official channels. In this article, we discuss the paucity of UK-based research pertaining to the prevalence and impact of sexual harassment in the military, explore potential reasons for this gap in knowledge and outline future directions and priorities for academic research.

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Hearing threshold shifts among military pilots of the Israeli Air Force

Background

Military aviators are potentially at risk for developing noise-induced hearing loss. Whether ambient aircraft noise exposure causes hearing deficit beyond the changes attributed to natural ageing is debated. The aim of this research was to assess changes in hearing thresholds of Israeli Air Force (IAF) pilots over 20 years of military service and identify potential risk factors for hearing loss.

Methods

A retrospective cohort analysis was conducted of pure-tone air conduction audiograms of pilots, from their recruitment at 18 years of age until the last documented medical check-up. Mean hearing thresholds were analysed in relation to age, total flight hours and aircraft platform. Comparisons were made to the hearing thresholds of air traffic controllers (ATCs) who were not exposed to the noise generated by aircraft while on duty.

Results

One hundred and sixty-three pilots were included, with flying platforms ranging from fighter jets (n=54), combat helicopters (n=27), transport helicopters (n=52) and transport aircraft (n=30). These were compared with the results from 17 ATCs. A marked notch in the frequency range of 4–6 kHz was demonstrated in the mean audiograms of all platforms pilots, progressing with ageing. Hearing threshold shifts in relation to measurements at recruitment were first noted at the age of 30 years, particularly at 4 kHz (mean shift of 2.97 dB, p=0.001). There was no statistical association between flying variables and hearing thresholds adjusted for age by logistic regression analysis.

Conclusions

The audiometric profile of IAF pilots has a pattern compatible with noise exposure, as reflected by characteristic noise notch. However, no flight variable was associated with deterioration of hearing thresholds, and no significant difference from non-flying controls (ATCs) was seen.

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