Liquid chromatography–tandem mass spectrometry method for simultaneous determination of three N-7-guanine adducts of the active epoxides of prodrug treosulfan in DNA in vitro

Publication date: 1 June 2019

Source: Talanta, Volume 198

Author(s): Michał Romański, Konrad Rotecki, Bartosz Nowicki, Artur Teżyk, Franciszek K. Główka

Abstract

Prodrug treosulfan undergoes a pH and temperature-dependent activation to the monoepoxide intermediate (EBDM) and (2S,3S)-1,2:3,4-diepoxybutane (DEB). The latter DNA cross-linker is presently believed to mainly account for the pharmacological action of treosulfan. However, neither respective monoadducts nor cross-links have been isolated from treosulfan-treated DNA, and the exact alkylation mechanism of the treosulfan epoxides is unclear. In this paper, liquid chromatography method with tandem mass spectrometry detection (LC-MS/MS) for simultaneous determination of the N-7-guanine adducts of EBDM and DEB − (2′S,3′S)-N-7-(2′3′-dihydroxy-4′-methylsulfonyloxybut-1′-yl)guanine (HMSBG), N-7-(2′,3′,4′-trihydroxybut-1′-yl)guanine (THBG), and 1,4-bis(N-7-guanyl)butane-2,3-diol cross-link (bis-N7G-BD) − in calf-thymus DNA has been developed and validated for the first time. The mixture of drug-free nucleic acid with the analytes and ¹⁵N-isotope labeled internal standards underwent a mild acid thermal hydrolysis and ultrafiltration (cut-off 10 kDa). Following offline LC purification, the analytes and internal standards were determined in the LC-MS/MS system with an electrospray interface. Complete resolution of THBG, HMSBG, and bis-N7G-BD was accomplished on a Zorbax Eclipse C18 column using gradient elution with a mobile phase composed of 0.1% formic acid and acetonitrile. Calibration curves were linear in the ranges: THBG 0.2–200 pmol, HMSBG 0.2–20 pmol, and bis-N7G-BD 0.4–40 pmol. The limits of quantitation allowed to determine the adducts at concentration of 330 or 660 per 10⁹ DNA nucleotides. The LC-MS/MS method was adequately precise (coefficient of variation ≤ 16.7%) and accurate (relative error ≤ 17.7%). Calibration standards were stable for 14 days at –25 °C. The validated method enabled determination of THBG, HMSBG, and bis-N7G-BD in calf thymus DNA treated with treosulfan at pH 7.2 and 37 °C, which constitutes a novel bioanalytical application. To the authors' best knowledge, the quantification of THBG and bis-N7G-BD in one analytical run is also reported for the first time.

Graphical abstract

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Comparison of hyperspectral imaging techniques for the elucidation of falsified medicines composition

Publication date: 1 June 2019

Source: Talanta, Volume 198

Author(s): Laureen Coic, Pierre-Yves Sacré, Amandine Dispas, Abdoul Karim Sakira, Marianne Fillet, Roland D. Marini, Philippe Hubert, Eric Ziemons

Abstract

Hyperspectral imaging has shown a high potential to analyze falsifications of solid pharmaceutical products since the last decade. Thanks to the non-destructive, ecological and non-invasive properties, it is a preferred technique for these kinds of applications. Moreover, thanks to the spectroscopic properties, it is possible to detect as well organic compounds as inorganic compounds in a single analysis. Therefore, we recommend using it as second-line laboratory analysis technique. Raman microscopy and Fourier Transform Infrared (FT-IR) microscopy are two interesting techniques that are complementary. In this study, the potential of the two hyperspectral imaging techniques is evaluated to elucidate the composition of falsified antimalarial tablets. Hyperspectral data are analyzed by Multivariate Curve Resolution-Alternating Least Square (MCR-ALS). The results obtained from this study show that Raman hyperspectral imaging seems to be more suited to detect low dosed compounds possibly due to a smallest sampling volume. It has been also possible to link formulations of falsified samples of two different brands.

Graphical abstract

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Electrochemical determination of antihypertensive drugs by employing costless and portable unmodified screen-printed electrodes

Publication date: 1 June 2019

Source: Talanta, Volume 198

Author(s): Ahmed A. Khorshed, Mohamed Khairy, Craig E. Banks

Abstract

Hypertension increases the risk of heart disease and stroke, is commonly known as a silent killer disease and considered as one of the key risk factor for premature death and disability over the world. Herein, we report for the first time a sensitive, costless and reproducible voltammetric method for individual determination of five antihypertensive drugs namely, propranolol (PRO), timolol (TIM), amlodipine (AML), amiloride (AMI) and triamterene (TRI) using differential pulse voltammetry at bare/unmodified screen-printed carbon electrodes (SPEs) in presence of sodium dodecyl sulfate (SDS). Each drug exhibits an electrochemical signal in aqueous media which is significantly enhanced in presence of optimized concentration of SDS due to accumulation of the protonated drug molecules and electrostatically interaction with negatively charged micellar structures. As a result, the spherical micellar orientation of SDS onto the graphitic surface of SPEs offered the analytically sensitive determination of the target drugs over a wide linear concentration range with nano-molar detection limits possible negating the need for any complicated surface modifications. Finally, the proposed voltammetric method was successfully utilized in the individual determination of the target antihypertensive drugs in pharmaceutical formulations and human urine samples.

Graphical abstract

Electrochemical analyses of antihypertensive drugs (propranolol, timolol, amlodipine, amiloride and triamterene) were explored by employing unmodified screen-printed electrode (SPE) in micellar media. The SPE offered a costless, portable, sensitive, stable and reproducible sensor for detection of these drugs in pharmaceutical dosage and human fluid.

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Thermogravimetry coupled to an atmospheric pressure photo ionization quadrupole mass spectrometry for the product control of pharmaceutical formulations and the analysis of plasticizers in polymers

Publication date: 1 June 2019

Source: Talanta, Volume 198

Author(s): Dominik Brecht, Florian Uteschil, Oliver J. Schmitz

Abstract

The development of a thermogravimetry coupled to an atmospheric pressure photoionization mass spectrometry (TG-APPI-MS) with a high temperature and flexible transfer line is presented. A method was developed to analyze plasticizers in solution which consist of a solvent evaporation step and subsequent evaporation of the analyte. These solutions of dibutyl phthalate (DBP) in hexane were used to investigate the repeatability (RSD: 3.6%) and linearity (R²: 0.9995) of the new developed system. With the new device the detection of different phthalates in a standardized PVC (polyvinyl chloride) polymer is shown. On the example of ASA, the degradation of a pharmaceutical drug is investigated. The dimerization and the possible trimerization of ASA during the thermal degradation is shown. Ten tablets of different ASA manufacturers were analyzed with the new developed analysis platform. The active substance was found in every tablet. Differences in mass spectral data as well as the studying of the pack insert were used to assign the tablets to companies and their subsidiaries. A unique formulation of ASA was found to have a different mass pattern when analyzed with TG-APPI-qMS. The developed device is a promising tool for the product control and the identification of falsified drugs.

Graphical abstract

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One-step fabrication of cinchona-based hybrid monolithic chiral stationary phases via photo-initiated thiol-ene polymerization for cLC enantioseparation

Publication date: 1 June 2019

Source: Talanta, Volume 198

Author(s): Shujuan Ma, Yan Wang, Haiyang Zhang, Ya Li, Junjie Ou, Yinmao Wei, Mingliang Ye

Abstract

Although various click polymerization reactions (thiol-ene, thiol-yne, thiol-Michael, thiol-epoxy and amine-epoxy) have been utilized to prepare either hybrid or organic monolithic columns with homogeneous network structures, there were few reports on fabrication of monolithic CSPs via click polymerization. Herein, a fast and robust approach was explored to fabricate cinchona-based monolithic hybrid CSPs via photo-initiated thiol-ene polymerization within 10 min in one step. A self-synthesized octakis(3-mercaptopropyl) octasilsesquioxane (POSS-SH) was polymerized with phenylisocyanate cinchonidine (PCD) and (+)-N,N'-diallyl-L-tartardiamide (DATDA) or 1,2,4-trivinylcyclohexane (TVCH). The resulting two kinds of as-synthesized monolithic CSPs, poly(POSS-co-DATDA-co-PCD) and poly(POSS-co-TVCH-co-PCD), were evaluated for cLC enantioseparation of acidic racemates. It was found that they exhibited different enantioseparation ability due to using different multivinyl crosslinkers. The influence of ACN content in mobile phase on the enantioseparation of acidic racemates was investigated. The separation mechanism was also discussed on the basis of a comparison of enantioseparation on two kinds of hybrid monolithic CSPs.

Graphical abstract

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Consumer electronics devices for DNA genotyping based on loop-mediated isothermal amplification and array hybridisation

Publication date: 1 June 2019

Source: Talanta, Volume 198

Author(s): Luis A. Tortajada-Genaro, Eric Seiti Yamanaka, Ángel Maquieira

Abstract

Consumer electronic technologies offer practical performances to develop compact biosensing systems intended for the point-of-care testing of DNA biomarkers. Herein a discrimination method for detecting single nucleotide polymorphisms, based on isothermal amplification and on-chip hybridisation, was developed and integrated into user-friendly optical devices: e.g., USB digital microscope, flatbed scanner, smartphone and DVD drive. In order to adequately identify a single base change, loop-mediated isothermal amplification (LAMP) was employed, with high yields (8 orders) within 45 min. Subsequently, products were directly hybridised to the allele-specific probes attached to plastic chips in an array format. After colorimetric staining, four consumer electronic techniques were compared. Sensitive precise measurements were taken (high signal-to-noise ratios, 10-μm image resolution, 99% scan-to-scan reproducibility). These features confirmed their potential as analytical tools, are a competitive alternative to fluorescence scanners, and incorporate additional advantages, such as user-friendly interface and connectivity for telemedicine needs. The analytical performances of the integrated platform (assay and reader) in the human samples were also excellent, with a low detection limit (100 genomic DNA copies), and reproducible (<15%) and cheap assays (< 10 €/test). The correct genotyping of a genetic biomarker (single-nucleotide polymorphism located in the GRIK4 gene) was achieved as the assigned genotypes agreed with those determined by using sequencing. The portability, favourable discriminating and read-out capabilities reveal that the implementation of mass-produced low-cost devices into minimal-specialised clinical laboratories is closer to becoming a reality.

Graphical abstract

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Facile fabrication of visible light photoelectrochemical immunosensor for SCCA detection based on BiOBr/Bi2S3 heterostructures via self-sacrificial synthesis method

Publication date: 1 June 2019

Source: Talanta, Volume 198

Author(s): Dawei Fan, Chunzhu Bao, Xin Liu, Jinhui Feng, Dan Wu, Hongmin Ma, Huan Wang, Qin Wei, Bin Du

Abstract

A novel visible light photoelectrochemical immunosensor based on BiOBr/Bi₂S₃ heterostructures was fabricated to detect squamous cell carcinoma antigen (SCCA). Bi₂S₃ nanoparticles formed on the BiOBr microflowers by the self-sacrificial synthesis method based on the facile reaction between BiOBr and S^2- ions. The BiOBr/Bi₂S₃ composites exhibited excellent visible light photoelectrochemical activity, when ascorbic acid (AA) was employed as a perfect electron donor. The photocurrent intensity of BiOBr/Bi₂S₃ modified ITO electrode arrived at around 20 µA, which was approximately 30 times than that of pure BiOBr. Dopamine formed easily polydopamine film via self-polymerization on the surface of BiOBr/Bi₂S₃ composites to immobilize SCCA antibody. Under the optimal condition, this photoelectrochemical immunosensor realized the ultrasensitive determination of SCCA. With the logarithm of SCCA concentration in the range of 0.001–75 ng mL⁻¹, the specific binding between SCCA and antibody led to the linearly decrease of photocurrent signal with a low detection limit of 0.3 pg mL⁻¹ (S/N = 3). This facilely constructed photoelectrochemical immunosensor maybe have promising practical application in photocatalysis, analytical detection and biosensor, etc.

Graphical abstract

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A portable and quantitative biosensor for cadmium detection using glucometer as the point-of-use device

Publication date: 1 June 2019

Source: Talanta, Volume 198

Author(s): Lingwen Zeng, Junyu Gong, Peisen Rong, Chengshuai Liu, Junhua Chen

Abstract

As an ubiquitous heavy metal pollutant, cadmium ion (Cd²⁺) is detrimental to food and human health even at low concentrations. Conventional methods require costly instruments and cannot meet the requirements of on-site analysis. Here we report the use of a personal glucose meter (PGM) as the point-of-use (POU) device for portable and quantitative detection of Cd²⁺. The specific recognition between the aptamer and Cd²⁺ trigger the recycling signal amplification process by exonuclease III (Exo III). After successive hybridization and cleavage reactions, numerous single-stranded DNA were liberated on the surface of the magnetic bead. An invertase-conjugated DNA that is complementary to the single-stranded DNA is introduced into the sensing system. After magnetic separation, the invertase conjugates hydrolyze sucrose into glucose, thus establishing direct conversion of Cd²⁺ concentration to glucose amount, which can be directly quantified by a PGM. Thanks to the synergistic signal amplification of Exo III and invertase, the POU device greatly improves the sensitivity for Cd²⁺ analysis, with a detection limit of 5 p.M. With the advantages of portability, cost-effectiveness, wide availability, and ease of use, the PGM-based detector has the potential to be used by the public as a routine tool for reliable and quantitative detection of Cd²⁺.

Graphical abstract

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Automated solid phase extraction and electrospray chip based on programmatic pneumatic micro-valves

Publication date: 1 June 2019

Source: Talanta, Volume 198

Author(s): Xiahong Wei, Yinyin Hao, Xueying Huang, Yijun Hu, Bo Xiong

Abstract

Microfluidic chips coupled with electrospray ionization (ESI) mass spectrometry (MS) is an analytical platform with high detection throughputs and low sample consumptions. However, its applications in probing real samples are limited by the absence of reliable on-chip sample pretreatments, which are indispensable due to both the low contents of analytes and the poor salt tolerance of ESI MS. Herein, we propose an automated extraction and ESI chip (AEEC), consisting of a solid phase extraction (SPE) zone, seven on-chip pneumatic micro-valves, a monolithic ESI nozzle, and other components, to implement on-chip SPE prior to on-line ESI for analytes. In the SPE zone, magnetic silica beads were immobilized by magnets, and used as the SPE sorbent. Additionally, open and closed statuses of all micro-valves were simultaneously controlled by turning off and on applied pneumatic pressures, thus regulating the direction of various flows in AEEC. Further, the SPE in AEEC, consisting of sample introduction and extraction, elution introduction, and analytes elution, was automatically implemented by regulating the direction of both sample and elution flows in AEEC. After these steps, the analytes elution was on-line introduced to the monolithic ESI nozzle, at which the ESI for analytes was achieved. After optimizations, the AEEC-MS method was used to investigate two standard chemicals and ten pesticides, achieving a limit of detection and an enrichment ratio between 0.10 and 0.75 ng μL⁻¹ and 2.1–6.2, respectively. In addition, linear calibration curves with and without the SPE beads were compared, demonstrating the effect of the automated SPE in improving reliability and sensitivity of the AEEC method. Finally, we applied AEEC to quantify a new herbicide, quinotrione, in sorghum plant as 0.176 mg kg⁻¹ (RSD=5.70%), presenting an improved error compared with related reports. With the AEEC method, a SPE and ESI MS investigation for analytes could be automatically implemented within 300 s, effectively reducing random error and analytical time compared with manual strategies.

Graphical abstract

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Cam-based vibration-counter-balanced laser-induced fluorescence scanner for multiplexed capillary detection

Publication date: 1 June 2019

Source: Talanta, Volume 198

Author(s): Guanbin Li, Shili Wang, Zaifang Zhu, Apeng Chen, Shaorong Liu

Abstract

Laser-induced fluorescence (LIF) rotary scanners have been successfully used for multiplexed capillary detection. However, these scanners have a limitation that the capillaries have to be assembled in a circular format, which can be inconvenient for certain applications. A linear LIF scanner works well for flat parallel capillary arrays, but motor accelerations/decelerations (for direction changes) and scanning head vibrations introduce high instrumental noises. The number of capillaries that can be scanned by a linear scanner is limited because of the above constraints. We have constructed a cam-based scanner in an attempt to address these issues. A cam-based scanner eliminates the motor accelerations/decelerations but not the scanning head vibrations. In this work, we attach a second scanning head to the cam on the opposite side of the first scanning head to counter-balance the mechanical vibrations. With this modification, we improve the limit of detection by more than 3 times (from 69 pM to 20 pM fluorescein). We also increase the capillary number capacity by more than 6 times; the total number of capillaries that can be scanned is 426 if 150-μm-o.d. capillaries are used or 320 if 200-μm-o.d. capillaries are used. To demonstrate the utility of this instrument, we assemble a 99-capillary array on one capillary holder and perform capillary electrophoresis of two fluorescent dyes; separations in all capillaries are successfully monitored simultaneously. We also apply it for detecting fluorescently labeled proteins resolved by 24 s-dimension capillaries in a chip-capillary hybrid device; two-dimensional separation results are nicely produced.

Graphical abstract

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Aflatoxins screening in non-dairy beverages by Mn-doped ZnS quantum dots – molecularly imprinted polymer fluorescent probe

Publication date: Available online 14 February 2019

Source: Talanta

Author(s): Anis Chmangui, Mohamed Ridha Driss, Soufiane Touil, Pilar Bermejo-Barrera, Sondes Bouabdallah, Antonio Moreda-Piñeiro

Abstract

Synthesized molecularly imprinted polymer (MIP) materials have been anchored on the surface of PEG-Mn-doped ZnS quantum dots (QDs) to develop a fluorescence probe for aflatoxins (AFs) recognition/determination in non-dairy beverages. MIP synthesis used 5,7-dimethoxycoumarin (DMC) as a dummy template molecule, and methacrylic acid (MAA) as a functional monomer. Under optimized conditions (1.25 mL of 5 mg L⁻¹ MIP-PEG-ZnS QDs solution, pH 5.0, and 12 min delay time before scanning), the prepared MIP-QDs composite was found to offer high affinity and selectivity for AFs (AFB1, AFB2, AFG1 and AFG2). A fast fluorimetric screening method (total AFs assessment) was therefore feasible. The limits of detection (LOD) and quantification (LOQ) were 0.016 and 0.053 mg L⁻¹, respectively. Analytical recoveries (inter- and intra-day assays) were from 99±4% to 107±5%, with RSD (intra-day assay) lower than 13, and RSD (inter-day) lower than 7%. The optimized method was applied for total AFs assessment in several non-dairy beverage samples.

Graphical abstract

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Determination of uric acid in serum using an optical sensor based on binuclear Pd(II) 2-pyrazinecarboxamide - bipyridine doped in a sol gel matrix

Publication date: Available online 13 February 2019

Source: Talanta

Author(s): S.G. Hashem, M.M. Elsaady, H.G. Afify, W.E. Omer, A.O. Youssef, Maged El-Kemary, M.S. Attia

Abstract

A new highly green luminescent binuclear palladium 2-pyrazinecarboxamide-bipyridine complex [Pd(pyc)(bpy)] was prepared and characterized. The binuclear Pd(pyc)(bpy) complex doped in sol-gel matrix has a strong luminescence intensity at 547 nm with λ_ex =330 nm in water The method depends on the quenching of the luminescence intensity of the binuclear Pd(pyc)(bpy) complex at 547 nm by different concentrations of uric acid. The remarkable quenching of the luminescence intensity of the binuclear Pd(pyc)(bpy) complex, doped in a sol-gel matrix, by uric acid was successfully used for the determination of uric acid in serum samples of patients with hypouricemia disease. The calibration plot was achieved over the concentration 3.9 ×10⁻⁹ to 1.2 × 10⁻⁴ mol L⁻¹uric acid with a correlation coefficient of 0.9 and a detection limit of 1.8 × 10⁻¹⁰ mol L⁻¹. The method was used satisfactorily for the assessment of the uric acid in a number of serum samples collected from various patients with Hypouricemia disease.

Graphical abstract

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Adaptive and sensitive fibre-optic fluorimetric transducer for air- and water-borne analytes

Publication date: Available online 12 February 2019

Source: Talanta

Author(s): Alhulw H Alshammari, Abraham Kirwa, Alan Dunbar, Martin Grell

Abstract

A sensitive fibre optic fluorescence intensity meter has been designed and built as a transducer to detect quenching of conjugated polymer fluorescence with minimum adjustment between air- and waterborne analytes. Only generic, commercially available parts including optical fibres, solvents, airbrush, standard optical and electronic parts, and a digital lock-in amplifier have been used, avoiding the need for a fluorescence spectrometer. To test the instrument, optical fibres were sensitised with the generic fluorescent poly(phenylene-vinylene) derivative MDMO-PPV and exposed to a variety of vapour pressures, and concentrations in water, of the nitroaromatic explosive 2,4 dinitrotoluene (DNT). We establish dimensionless Stern-Volmer constants (K_SV) and limit-of-detection (LoD) for air- and water-borne DNT as K_SV(air) = 1.4 ×10⁷vs. K_SV(water) = 5.8 ×10⁶ and LoD(air) = 10.9 ppb and LoD(water) = 56 ppb. These LoDs compare favourably to prior reports. We consider our study of the MDMO-PPV / DNT system as a successful test of our transducer design and recommend its wider use.

Graphical abstract

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Investigation of lipid modifications in J774 macrophages by vibrational spectroscopies after eicosapentaenoic acid membrane incorporation in unloaded and cholesterol-loaded cells

Publication date: Available online 12 February 2019

Source: Talanta

Author(s): Sana Tfaili, Almar Al Assaad, Natalie Fournier, Fatima Allaoui, Jean-Louis Paul, Pierre Chaminade, Ali Tfayli

Abstract

Atherosclerosis is an inflammatory disease of the arterial wall caused by the formation of an atheroma plaque in the vessel wall. The uptake of modified LDL lipoproteins by sub-endothelial macrophages induces the latter's transformation into foam cells, which is the key step of atheroma plaque formation. The modifications of neutral lipids caused by foam cells formation are marked by the appearance of lipid droplets. Polyunsaturated fatty acids (PUFAs) incorporation into membrane phospholipids (PL) modifies their composition, which may influence membrane protein functions. The incorporation of eicosapentaenoic acid (EPA) reduces the anti-atherogenic ABCA1 (ATP Binding Cassette transporter A1) pathway and induces PLs modifications. In order to study lipids directly in the cell environment, a comparative study is conducted by vibrational spectroscopies on murine macrophages J774, loaded or not with cholesterol, which were enriched or not with eicosapentaenoic acid (EPA). The study enabled to identify changes in the spectral signature after cells enrichment with fatty acid (FA) relying only on chemometric analysis without deuterium labelling. Results highlighted spectral changes in the regions attributed to lipids associated to triglycerides, phospholipids and cholesterol in both Raman and IR.

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Electrochemical assay for 20S proteasome activity and inhibition with anti-cancer drugs

Publication date: Available online 12 February 2019

Source: Talanta

Author(s): Catarina Sofia Henriques de Jesus, Ana Maria Chiorcea-Paquim, Madalina Maria Barsan, Victor Constantin Diculescu

Abstract

The majority of eukaryotic regulated protein turnover is performed by the proteasome, a multi-catalytic enzyme. Due to the fact that proteasome enzyme abnormal functioning was observed in different malignant cells, the proteasome is becoming a target for medical treatment. In order to evaluate the mechanisms of action of pharmaceutical compounds on proteasome enzyme inhibition, detecting and characterizing its activity is essential. An electrochemical assay that allows the monitoring of the chymotrypsin-like activity and inhibition of the 20 S proteasome enzyme, based on the electrochemical detection of an electroactive compound released upon proteolysis of an adequate chymotrypsin-substrate is described. By employing differential pulse voltammetric measurement, the activity of the 20 S proteasome enzyme was investigated for different incubation times of 20 S with oligopeptide substrate as well as for different concentrations of substrate. Enzyme kinetic parameters were determined by voltammetry and the electrochemical assay compared with fluorescence spectroscopy. Electrochemical quartz crystal microbalance and atomic force microscopy were also used to investigate substrate interaction with the 20 S proteasome and their adsorption at the electrode surface. Finally, the new electrochemical assay allowed to investigate the mechanisms of two different proteasome inhibitor drugs, bortezomib and oprozomib, underlying the applicability of the assay for understanding proteasome inhibitor action.

Graphical abstract

Scheme of the 20S proteasome catalytic activity and principle of the electrochemical detection.

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Chromatographic Separation of Hemoglobin Variants Using Robust Molecularly Imprinted Polymers

Publication date: Available online 12 February 2019

Source: Talanta

Author(s): Ka Zhang, Tongchang Zhou, Karin Kettisen, Lei Ye, Leif Bülow

Abstract

Devising a robust, efficient and cost effective hemoglobin (Hb) purification strategy is one of the key challenges in the development of Hb-based blood substitutes. The aim of this study was to use molecularly imprinted polymers (MIPs) as a novel and efficient chromatographic resin to selectively recognize and purify different Hb variants. The results showed that the Hb-MIP material developed here could selectively recognize and purify various Hb directly from either crude E. coli extracts or human body fluids, such as blood plasma and cerebrospinal fluid (CSF), in one-step. The dynamic binding capacity at 10% breakthrough was around 7.4 mg mL^-1resin for adult Hb (HbA) and fetal Hb (HbF). This chromatographic material also allowed identification of changes related to amino acid substitutions on the Hb protein surface. For instance, when an additional lysine residue was introduced, the HbA αY42K mutant eluted later in an Hb-MIP column than wildtype HbA. Additional negative charges on the protein surface, such as aspartate, mitigated the interaction between the protein and imprinted polymers, and therefore an αA19D-αA12D HbF mutant eluted earlier, at −2.7 column volumes compared to wildtype HbF.

Graphical abstract

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Evaluation of the sensitivity of R1ρ MRI to pH and macromolecular density

Publication date: Available online 14 February 2019

Source: Magnetic Resonance Imaging

Author(s): Syed O. Ali, Petros Fessas, Joshua D. Kaggie, Fulvio Zaccagna, Gavin Houston, Scott Reid, Martin J. Graves, Ferdia A. Gallagher

Abstract

The tumor microenvironment is characteristically acidic and this extracellular acidosis is known to play a role in carcinogenesis and metastasis and can affect tumor chemosensitivity and radiosensitivity. Intracellular pH has been used as a possible biomarker of salvageable tissue in ischemic stroke. A non-invasive MRI-based approach for the determination and imaging of cerebral pH would be a powerful tool in cancer diagnosis and monitoring, as well as stroke treatment planning. Several pH-based MRI imaging approaches have been proposed but for these to be useful, disentangling the effects of pH from other parameters which may affect the measured MRI signal is crucial to ensure accuracy and specificity. R₁ relaxation in the rotating frame (R₁ρ) is an example of a method that has been proposed to probe pH in vivo using MRI. In this study, we have investigated the relationship between R₁ρ, pH, and macromolecular density in vitro using phantoms and in human volunteers. Here we show that the rate of R₁ρ relaxation (=1/T₁ρ) varies with pH but only in the presence of macromolecules. At constant pH, phantom macromolecular density inversely correlated with R₁ρ. R₁ρ imaging of the normal human brain demonstrated regional heterogeneity with significant differences between structurally distinct regions, which are likely to be independent of pH. For example, R₁ρ was higher in the basal ganglia compared to grey matter and higher in grey matter compared to white matter. We conclude that R₁ρ cannot be reliably used to image tissue pH without deconvolution from the effects of local tissue macromolecular composition.

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Lung Volume Reduction Under Spontaneous Ventilation in a Patient with Severe Emphysema.

Lung Volume Reduction Under Spontaneous Ventilation in a Patient with Severe Emphysema.

Am J Case Rep. 2019 Jan 30;20:125-130

Authors: Lan L, Li J, Xu X, Cen Y

Abstract
<strong>BACKGROUND</strong> One-lung ventilation under general anesthesia is necessary for most thoracic surgical procedures. However, adverse effects may derive from mechanical ventilation in emphysema patients. At present, lung volume reduction surgery under spontaneous ventilation may attenuate these adverse effects. <strong>CASE REPORT</strong> We present a case of left-side secondary spontaneous pneumothorax in a 71-year-old male who had a history of chronic obstructive pulmonary disease for 12 years, combined with a contralateral giant bulla. After conservative therapies, bubble extravasation still persisited on the left side of the drainage tube. Lung volume reduction surgery under spontaneous ventilation was considered. The patient recovered fast though intraoperative critical respiratory management, effective pain control, and suitable sedation, and he was discharged from the hospital 3 days after the operation. <strong>CONCLUSIONS</strong> Video-assisted thoracic surgery under spontaneous ventilation may be an alternative method for lung volume reduction surgery in emphysema patients who also have secondary spontaneous pneumothorax and a contralateral giant bulla.

PMID: 30759075 [PubMed - in process]

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A Rare Case of Isolated Idiopathic Inferior Mesenteric Artery Dissection.

A Rare Case of Isolated Idiopathic Inferior Mesenteric Artery Dissection.

Am J Case Rep. 2019 Jan 29;20:121-124

Authors: Ueno D, Urata R, Ono K, Sakaue Y, Hori Y, Yoshioka K, Kikai M, Nomura T, Keira N, Tatsumi T

Abstract
<strong>BACKGROUND</strong> Isolated dissection of a mesenteric artery is very rare and usually presents with acute gastrointestinal symptoms. There have been previously published reports on the isolated dissection of the superior mesenteric artery. However, isolated dissection of the inferior mesenteric artery is rare. <strong>CASE REPORT</strong> A 43-year-old man presented with sudden onset of lower abdominal pain. Abdominal computed tomography (CT) imaging confirmed isolated dissection of the inferior mesenteric artery. To prevent exacerbation of the dissection, his systolic blood pressure was controlled to <140 mmHg, and his progress was observed for ten days while in hospital during which time the dissection stabilized. There was no extension of the dissection. After three years, the dissection had healed and did not recur. <strong>CONCLUSIONS</strong> To our knowledge, this is the first case report of isolated dissection of the inferior mesenteric artery that resolved spontaneously. This case shows the importance of blood pressure control in the management of arterial dissection.

PMID: 30759073 [PubMed - in process]

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A Case of Eosinophilic Gastroenteritis Associated with Eosinophilic Ascites Diagnosed by Full-Thickness Biopsy of the Small Intestine.

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A Case of Eosinophilic Gastroenteritis Associated with Eosinophilic Ascites Diagnosed by Full-Thickness Biopsy of the Small Intestine.

Am J Case Rep. 2019 Feb 13;20:189-193

Authors: Salah HT, Al-Hussaini HF, Alqaraawi AM, Alanazi KM

Abstract
BACKGROUND Eosinophilic gastroenteritis is a rare disease, characterized by infiltrates of eosinophils in the intestinal mucosa, muscularis propria, and serosa. Eosinophilic gastroenteritis is due to Type 1 hypersensitivity and can be associated with other atopic diseases. The clinical course of eosinophilic gastroenteritis varies depending on the location, extent, and depth of eosinophilic infiltration of the gastrointestinal tract, which can make the diagnosis challenging. A case of eosinophilic gastroenteritis associated with eosinophilic ascites is presented that emphasizes the importance of full-thickness intestinal biopsy, which includes the muscularis propria, to allow the definitive diagnosis to be made. CASE REPORT A 28-year-old man presented with vague abdominal pain, nonspecific gastrointestinal symptoms, unintentional weight loss, and progressive ascites during the previous several months. A diagnosis of eosinophilic gastroenteritis was made after the exclusion of other possible causes, which was confirmed by histopathology of a full-thickness intestinal biopsy. The patient was treated with steroids. At one-month follow-up, the patient reported reduced abdominal pain. CONCLUSIONS A case of eosinophilic gastroenteritis associated with eosinophilic ascites is presented that emphasizes the importance of full-thickness intestinal biopsy, which includes the muscularis propria, to allow the definitive diagnosis to be made.

PMID: 30755542 [PubMed - in process]

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Striatal spreading depolarization: Possible implication in levodopa-induced dyskinetic-like behavior.

Striatal spreading depolarization: Possible implication in levodopa-induced dyskinetic-like behavior.

Mov Disord. 2019 Feb 13;:

Authors: de Iure A, Napolitano F, Beck G, Quiroga Varela A, Durante V, Sciaccaluga M, Mazzocchetti P, Megaro A, Tantucci M, Cardinale A, Punzo D, Mancini A, Costa C, Ghiglieri V, Tozzi A, Picconi B, Papa SM, Usiello A, Calabresi P

Abstract
OBJECTIVE: Spreading depolarization (SD) is a transient self-propagating wave of neuronal and glial depolarization coupled with large membrane ionic changes and a subsequent depression of neuronal activity. Spreading depolarization in the cortex is implicated in migraine, stroke, and epilepsy. Conversely, spreading depolarization in the striatum, a brain structure deeply involved in motor control and in Parkinson's disease (PD) pathophysiology, has been poorly investigated.
METHODS: We characterized the participation of glutamatergic and dopaminergic transmission in the induction of striatal spreading depolarization by using a novel approach combining optical imaging, measurements of endogenous DA levels, and pharmacological and molecular analyses.
RESULTS: We found that striatal spreading depolarization requires the concomitant activation of D1-like DA and N-methyl-d-aspartate receptors, and it is reduced in experimental PD. Chronic l-dopa treatment, inducing dyskinesia in the parkinsonian condition, increases the occurrence and speed of propagation of striatal spreading depolarization, which has a direct impact on one of the signaling pathways downstream from the activation of D1 receptors.
CONCLUSION: Striatal spreading depolarization might contribute to abnormal basal ganglia activity in the dyskinetic condition and represents a possible therapeutic target. © 2019 International Parkinson and Movement Disorder Society.

PMID: 30759320 [PubMed - as supplied by publisher]

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Risk Factors for Sudden Unexpected Death in Epilepsy (SUDEP) and Their Mitigation.

Risk Factors for Sudden Unexpected Death in Epilepsy (SUDEP) and Their Mitigation.

Curr Treat Options Neurol. 2019 Feb 13;21(2):7

Authors: Whitney R, Donner EJ

Abstract
PURPOSE OF REVIEW: People with epilepsy have an increased risk of mortality when compared to the general population. Sudden unexpected death in epilepsy (SUDEP) is the most common cause of epilepsy-related death in children and adults. The purpose of this review is to discuss SUDEP, with an emphasis on SUDEP risk factors, their mitigation and prevention.
RECENT FINDINGS: SUDEP affects approximately 1 in 1000 people with epilepsy each year. Recent studies suggest that the incidence in children is similar to that of adults. The most important risk factor for SUDEP is the presence and frequency of generalized tonic-clonic seizures. The presence of nocturnal supervision may decrease risk along with the use of nocturnal listening devices. Underlying genetic influences, both cardiac and epilepsy-related may further alter risk. Risk mitigation strategies include reducing seizure frequency, optimizing therapy, and the use of nocturnal supervision/seizure detection devices. Risk factors for SUDEP are well established; however, pediatric specific risk factors have not been identified. Current prevention strategies are focused on reduction of risk factors and the possible role of seizure detection devices. More research is needed to better understand the varied underlying pathological mechanisms and develop targeted prevention strategies. Further understanding the genetic factors that influence SUDEP risk may potentially aid in understanding the underlying pathophysiology of SUDEP.

PMID: 30758730 [PubMed]

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Drug-resistant epilepsy in Indian children at a tertiary-care public hospital.

Drug-resistant epilepsy in Indian children at a tertiary-care public hospital.

Childs Nerv Syst. 2019 Feb 13;:

Authors: Kharod P, Mishra D, Juneja M

Abstract
BACKGROUND: Drug-resistant epilepsy (DRE), a condition in which seizures persist and seizure freedom is unlikely to be attained with further manipulation of anti-epileptic drugs, occurs in around 20% of children with epilepsy. This study was conducted with the aim to study the profile of Indian children with resistant epilepsy, using the new consensus definition of DRE.
METHODS: All children who had been attending the Pediatric Neurology Clinic regularly for at least 6 months were reviewed between April and September 2015. Children fulfilling the ILAE Commission on Therapeutic Strategies Consensus Proposal definition of DRE were enrolled for the study. After informed consent, the records were reviewed and disease-related data was entered in the study form. The data were analyzed to determine etiological factors and treatment gaps in children with DRE.
RESULTS: Fifty children (12 females) with median (range) age of 90 (11-159) months and follow-up of 17.9 (8.5-20) months were enrolled. The mean (standard deviation) age at seizure onset and start of anti-epileptic drugs (AED) were 1.8 (2.11) and 2.1 (2.09) years, respectively. The median (range) number of anti-epileptic drugs that had been tried in these children was 5 (2-9), with drug side effects leading to discontinuation in 8 (16%) patients. Only two patients had tried ketogenic diet; vagal nerve stimulation and epilepsy surgery had not been tried by any family, despite recommendation by the physicians in 7 children.
CONCLUSIONS: Majority of Indian children with DRE have onset of epilepsy in early infancy, and are infrequently provided access to newer non-pharmacological measures.

PMID: 30758667 [PubMed - as supplied by publisher]

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Clinical, Electroencephalographic Features and Prognostic Factors of Cefepime-Induced Neurotoxicity: A Retrospective Study.

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Clinical, Electroencephalographic Features and Prognostic Factors of Cefepime-Induced Neurotoxicity: A Retrospective Study.

Neurocrit Care. 2019 Feb 12;:

Authors: Li HT, Lee CH, Wu T, Cheng MY, Tseng WJ, Chang CW, Hsieh HY, Chiang HI, Lin CY, Chang BL, Lin WR, Lim SN

Abstract
BACKGROUND: The incidence of cefepime-induced neurotoxicity (CIN) has been previously underestimated, and there have only been sporadic reports from critical neurological settings. The present study aimed to investigate the potential factors associated with disease development, electroencephalography (EEG) sub-classification, and outcome measures.
METHODS: The 10-year medical records of patients who underwent EEG between 2007 and 2016 at a tertiary medical center in Taiwan, and developed encephalopathy after cefepime therapy were retrospectively reviewed. Age- and sex-matched controls were included for further analysis. Demographic data, the occurrence of clinical seizures, non-convulsive status epilepticus (NCSE), use of antiepileptic drugs (AEDs), receiving maintenance or urgent hemodialysis, EEG findings, and functional outcomes were analyzed. The Chi-square test and a logistic regression model were applied to survey significant prognostic factors relating to mortality.
RESULTS: A total of 42 CIN patients were identified, including 25 patients from wards and 17 from intensive care units; their mean age was 75.8 ± 11.8 years. Twenty-one patients (50%) had chronic kidney disease, and 18 (43%) had acute kidney injury. Among these patients, 32 (76%) received appropriate cefepime dose adjustment. Three patients had a normal renal function at the time of CIN onset. The logistic regression model suggested that maintenance hemodialysis and longer duration of cefepime use were independently associated with the development of CIN, with odds ratios of 3.8 and 1.2, respectively. NCSE was frequently noted in the CIN patients (64%). Generalized periodic discharge with or without triphasic morphology was the most common EEG pattern (38%), followed by generalized rhythmic delta activity and generalized spike-and-waves. AEDs were administered to 86% of the patients. A total of 17 patients (40%) did not survive to hospital discharge. Adequate cefepime dose adjustment and early cefepime discontinuation led to a better prognosis.
CONCLUSIONS: CIN was associated with high mortality and morbidity rates. Neurotoxic symptoms could still occur when the cefepime dose was adjusted, or in patients with normal renal function. Patients with maintenance hemodialysis or a longer duration of cefepime therapy tended to develop CIN. Early recognition of abnormal EEG findings allowed for the withdrawal of the offending agent, resulting in clinical improvements and a better prognosis at discharge.

PMID: 30756319 [PubMed - as supplied by publisher]

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A Classic Neurocysticercosis Case with an Unusual Complication.

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A Classic Neurocysticercosis Case with an Unusual Complication.

Eur J Case Rep Intern Med. 2018;5(1):000762

Authors: Rodrigues A, Neves D, Maury I, Sargento D, Pereira A

Abstract
Cysticercosis is triggered by infection with the larval form of the tapeworm Taenia solium. The usual sites for the development of cyscticerci are the central nervous system (neurocysticercosis - NCC), subcutaneous tissue, skeletal muscle, heart muscle, and the eye. Ocular cysticercosis is caused by the growth of the larvae within ocular tissues. The extraocular muscles form is the most common type of orbital cysticercosis. We report a case of a patient admitted with seizures secondary to NCC, who developed ocular symptoms after starting combined treatment with albendazole, praziquantel and dexamethasone. The investigation revealed a cystic lesion in the lateral rectus muscle.
LEARNING POINTS: Neurocysticercosis (NCC) is the main cause of epilepsy in someone coming from an endemic area; therefore, it is imperative to have a high index of suspicion.Ocular cysticercosis can present at the time of diagnosis or can be triggered by the cysticidal treatment.Before starting cysticidal treatment, systemic corticosteroid should be used in order to reduce the inflammatory response secondary to the release of toxins following the death of the parasite.

PMID: 30755977 [PubMed]

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Epilepsy gene therapy using an engineered potassium channel.

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Epilepsy gene therapy using an engineered potassium channel.

J Neurosci. 2019 Feb 12;:

Authors: Snowball A, Chabrol E, Wykes RC, Shekh-Ahmad T, Cornford JH, Lieb A, Hughes MP, Massaro G, Rahim AA, Hashemi KS, Kullmann DM, Walker MC, Schorge S

Abstract
Refractory focal epilepsy is a devastating disease for which there is frequently no effective treatment. Gene therapy represents a promising alternative, but treating epilepsy in this way involves irreversible changes to brain tissue, so vector design must be carefully optimized to guarantee safety without compromising efficacy. We set out to develop an epilepsy gene therapy vector optimized for clinical translation. The gene encoding the voltage-gated potassium channel Kv1.1, KCNA1, was codon-optimized for human expression and mutated to accelerate the channels' recovery from inactivation. For improved safety, this engineered potassium channel (EKC) gene was packaged into a non-integrating lentiviral vector under the control of a cell type-specific CAMK2A promoter. In a blinded, randomized, placebo-controlled pre-clinical trial, the EKC lentivector robustly reduced seizure frequency in a male rat model of focal neocortical epilepsy characterized by discrete spontaneous seizures. When packaged into an adeno-associated viral vector (AAV2/9), the EKC gene was also effective at suppressing seizures in a male rat model of temporal lobe epilepsy. This demonstration of efficacy in a clinically relevant setting, combined with the improved safety conferred by cell type-specific expression and integration-deficient delivery, identify EKC gene therapy as ready for clinical translation in the treatment of refractory focal epilepsy.SIGNIFICANCE STATEMENTPharmacoresistant epilepsy affects up to 0.3% of the population. Although epilepsy surgery can be effective it is limited by risks to normal brain function. We have developed a gene therapy that builds on a mechanistic understanding of altered neuronal and circuit excitability in cortical epilepsy. The potassium channel gene KCNA1 was mutated to bypass post-transcriptional editing, and packaged in a non-integrating lentivector to reduce the risk of insertional mutagenesis. A randomized, blinded pre-clinical study demonstrated therapeutic effectiveness in a rodent model of focal neocortical epilepsy. Adeno-associated viral delivery of the channel to both hippocampi was also effective in a model of temporal lobe epilepsy. These results support clinical translation to address a major unmet need.

PMID: 30755487 [PubMed - as supplied by publisher]

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Posterior reversible encephalopathy syndrome due to hypercalcaemia: a rare cause.

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Posterior reversible encephalopathy syndrome due to hypercalcaemia: a rare cause.

BMJ Case Rep. 2019 Feb 11;12(2):

Authors: Bolanthakodi N, Vidyasagar S, Varma M, Holla A

Abstract
Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological entity described by Hinchey et al in late 90's, characterised by variable associations of seizure activity, consciousness impairment ranging from confusion to coma, headaches, visual abnormalities, nausea/vomiting and focal neurological signs. Common causes are accelerated hypertension, eclampsia, preeclampsia, cytotoxic drug use and autoimmune diseases like systemic lupus erythematosus.We report a case of PRES in a 62-year-old female patient due to hypercalcemia secondary to vitamin D toxicity on treatment with calcium supplements and vitamin D for secondary hypoparathyroidism. She had seizures and visual defects on presentation which recovered completely with treatment of hypercalcemia.

PMID: 30755423 [PubMed - in process]

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Annexin A1-derived peptide Ac2-26 in a pilocarpine-induced status epilepticus model: anti-inflammatory and neuroprotective effects.

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Annexin A1-derived peptide Ac2-26 in a pilocarpine-induced status epilepticus model: anti-inflammatory and neuroprotective effects.

J Neuroinflammation. 2019 Feb 12;16(1):32

Authors: Gimenes AD, Andrade BFD, Pinotti JVP, Oliani SM, Galvis-Alonso OY, Gil CD

Abstract
BACKGROUND: The inflammatory process has been described as a crucial mechanism in the pathophysiology of temporal lobe epilepsy. The anti-inflammatory protein annexin A1 (ANXA1) represents an interesting target in the regulation of neuroinflammation through the inhibition of leukocyte transmigration and the release of proinflammatory mediators. In this study, the role of the ANXA1-derived peptide Ac2-26 in an experimental model of status epilepticus (SE) was evaluated.
METHODS: Male Wistar rats were divided into Naive, Sham, SE and SE+Ac2-26 groups, and SE was induced by intrahippocampal injection of pilocarpine. In Sham animals, saline was applied into the hippocampus, and Naive rats were only handled. Three doses of Ac2-26 (1 mg/kg) were administered intraperitoneally (i.p.) after 2, 8 and 14 h of SE induction. Finally, 24 h after the experiment-onset, rats were euthanized for analyses of neuronal lesion and inflammation.
RESULTS: Pilocarpine induced generalised SE in all animals, causing neuronal damage, and systemic treatment with Ac2-26 decreased neuronal degeneration and albumin levels in the hippocampus. Also, both SE groups showed an intense influx of microglia, which was corroborated by high levels of ionised calcium binding adaptor molecule 1(Iba-1) and monocyte chemoattractant protein-1 (MCP-1) in the hippocampus. Ac2-26 reduced the astrocyte marker (glial fibrillary acidic protein; GFAP) levels, as well as interleukin-1β (IL-1β), interleukin-6 (IL-6) and growth-regulated alpha protein (GRO/KC). These effects of the peptide were associated with the modulation of the levels of formyl peptide receptor 2, a G-protein-coupled receptor that binds to Ac2-26, and the phosphorylated extracellular signal-regulated kinase (ERK) in the hippocampal neurons.
CONCLUSIONS: The data suggest a neuroprotective effect of Ac2-26 in the epileptogenic processes through downregulation of inflammatory mediators and neuronal loss.

PMID: 30755225 [PubMed - in process]

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Epilepsy surgery: A therapeutic patient education program.

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Epilepsy surgery: A therapeutic patient education program.

Rev Neurol (Paris). 2018 Dec;174(10):726-730

Authors: Catenoix H, Feutrier C, Taffin F, Peverelli R, Rodot M, Robinson P, André-Obadia N

Abstract
Before the creation of a therapeutic patient education (TPE) program for epilepsy surgery, a needs analysis was conducted with 29 people, including patients (n=13), family members (n=9) and healthcare providers (n=7). Most of them highlighted the psychological difficulties of the surgical process, and the need for considerably more precise information concerning the immediate postoperative period. In addition, several patients and/or family members requested meeting with a patient who had undergone the surgery. The majority of subjects were interested in epilepsy-surgery TPE. These data were important in the creation of our TPE program and, more generally, for the management of these patients.

PMID: 30301566 [PubMed - indexed for MEDLINE]

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Overexpression of miRNA-137 in the brain suppresses seizure activity and neuronal excitability: A new potential therapeutic strategy for epilepsy.

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Overexpression of miRNA-137 in the brain suppresses seizure activity and neuronal excitability: A new potential therapeutic strategy for epilepsy.

Neuropharmacology. 2018 08;138:170-181

Authors: Wang W, Guo Y, He L, Chen C, Luo J, Ma Y, Li J, Yang Y, Yang Q, Du C, Zhang Y, Li Z, Xu X, Tian X, Wang X

Abstract
miRNA-137 is an extremely abundant miRNA in the central nervous system and is thought to be closely related to synaptic plasticity. Here, we report a previously unrecognized role of miRNA-137 in epilepsy. The expression of miRNA-137 was decreased both in patients with temporal lobe epilepsy (TLE) and in two different mouse models of epilepsy. Overexpression of miRNA-137 induced by an intrahippocampal injection of a specific agomir prolonged the latency to spontaneous recurrent seizures (SRSs) and reduced seizure severity in a mouse model of pilocarpine-induced epilepsy. Elevated levels of miRNA-137 also prolonged the latency to full kindling and reduced the seizure severity in a mouse model of pentylenetetrazol (PTZ)-kindled epilepsy. Suppression of miRNA-137 levels decreased the latency to the first SRS or the latency to full kindling and increased the seizure severity in both epileptic mouse models. Whole-cell patch-clamp recordings showed that overexpression of miRNA-137 reduced the excitability of pyramidal neurons in the hippocampal CA3a region in a Mg2+-free-induced brain slice model of epileptiform activity. This effect may have been achieved by the regulation of the frequency of miniature inhibitory postsynaptic currents (mIPSCs) and presynaptic inhibitory neurotransmitter release. These results suggest that elevated levels of miRNA-137 may exert an antiepileptic effect via a presynaptic neurotransmission mechanism. These data may provide a new potential target and therapeutic strategy for treating epilepsy in the future.

PMID: 29894770 [PubMed - indexed for MEDLINE]

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Hypertensive pregnancy complications in women with epilepsy and antiepileptic drugs: a population-based cohort study of first pregnancies in Norway.

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Hypertensive pregnancy complications in women with epilepsy and antiepileptic drugs: a population-based cohort study of first pregnancies in Norway.

BMJ Open. 2018 04 24;8(4):e020998

Authors: Danielsson KC, Borthen I, Morken NH, Gilhus NE

Abstract
OBJECTIVES: To estimate the risk of hypertensive pregnancy complications in women with epilepsy, with and without antiepileptic drugs, and assess the risk associated with the four most common antiepileptic drugs.
DESIGN: A population-based cohort study using linked data from the Medical Birth Registry of Norway and the Norwegian Prescription Database. Women with epilepsy with and without antiepileptic drugs were compared with women without epilepsy.
SETTING: Norway, 2004-2012.
PARTICIPANTS: All first pregnancies of women with epilepsy and women without epilepsy were included.
PRIMARY AND SECONDARY OUTCOME MEASURES: Main outcome measures were hypertensive pregnancy complications: a compound variable of any hypertensive disorder, gestational hypertension, mild pre-eclampsia, severe pre-eclampsia, early onset pre-eclampsia, eclampsia and HELLP syndrome (haemolysis, elevated liver enzymes, low platelets).
RESULTS: In total, 1778 pregnancies in women with epilepsy and 221 662 in women without epilepsy were analysed. 682 of the women with epilepsy used antiepileptic drugs, the most common in monotherapy being: lamotrigine (n=280), carbamazepine (n=94), levetiracetam (n=71) and valproate (n=51). There was an increased risk of any hypertensive disorder in women with epilepsy (adjusted OR (aOR) 1.2, 95% CI 1.0 to 1.5) and in the subcategory using valproat (aOR 2.9, 95% CI 1.3 to 6.4). The most frequent hypertensive complication was mild pre-eclampsia and the risk was increased in women with epilepsy (aOR 1.4, 95% CI 1.1 to 1.8) and women with epilepsy with valproat (aOR 3.3, 95% CI 1.2 to 9.4).
CONCLUSIONS: Women with epilepsy have an increased risk of mild pre-eclampsia, but not for the severe types of hypertensive pregnancy complications. Lamotrigine and levetiracetam do not predispose for mild pre-eclampsia, whereas valproate was associated with an increased risk of mild pre-eclampsia.

PMID: 29691249 [PubMed - indexed for MEDLINE]

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Quantitative expression and localization of GABAB receptor protein subunits in hippocampi from patients with refractory temporal lobe epilepsy.

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Quantitative expression and localization of GABAB receptor protein subunits in hippocampi from patients with refractory temporal lobe epilepsy.

Neuropharmacology. 2018 07 01;136(Pt A):117-128

Authors: Sheilabi MA, Battacharyya D, Caetano L, Thom M, Reuber M, Duncan JS, Princivalle AP

Abstract
This study investigates GABAB protein expression and mRNA levels in three types of specimens. Two types of specimens from patients with temporal lobe epilepsy (TLE), secondary to hippocampal sclerosis, sclerotic hippocampal samples (TLE-HS), and tissue from the structurally preserved non-spiking ipsilateral superior temporal gyrus (TLE-STG) removed from the same patient during epilepsy surgery; and third specimen is hippocampal tissue from individuals with no history of epilepsy (post-mortem controls, PMC). mRNA expression of GABAB subunits was quantified in TLE-HS, TLE-STG and PMC specimens by qRT-PCR. Qualitative and quantitative Western blot (WB) and immunohistochemistry techniques were employed to quantify and localize GABAB proteins subunits. qRT-PCR data demonstrated an overall decrease of both GABAB1 isoforms in TLE-HS compared to TLE-STG. These results were mirrored by the WB findings. GABAB2 mRNA and protein were significantly reduced in TLE-HS samples compared to TLE-STG; however they appeared to be upregulated in TLE-HS compared to the PMC samples. Immunohistochemistry (IHC) showed that GABAB proteins were widely distributed in PMC and TLE-HS hippocampal sections with regional differences in the intensity of the signal. The higher expression of mature GABAB protein in TLE-HS than PMC is in agreement with previous studies. However, these findings could be due to post-mortem changes in PMC specimens. The TLE-STG samples examined here represent a better 'control' tissue compared to TLE-HS samples characterised by lower than expected GABAB expression. This interpretation provides a better explanation for previous functional studies suggesting reduced inhibition in TLE-HS tissue due to attenuated GABAB currents. This article is part of the "Special Issue Dedicated to Norman G. Bowery".

PMID: 28782512 [PubMed - indexed for MEDLINE]

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Real-world data on discordance between estrogen, progesterone, and HER2 receptor expression on diagnostic tumor biopsy versus tumor resection material.

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Real-world data on discordance between estrogen, progesterone, and HER2 receptor expression on diagnostic tumor biopsy versus tumor resection material.

Breast Cancer Res Treat. 2019 Feb 13;:

Authors: Berghuis AMS, van Deurzen CHM, Koffijberg H, Terstappen LWMM, Sleijfer S, IJzerman MJ

Abstract
PURPOSE: The estrogen (ER), progesterone (PR), and HER2 status are essential in guiding treatment decisions in breast cancer patients. In daily life, the ER/PR/HER2 status is expected to be commonly tested twice, i.e., at diagnosis using material from tumor needle biopsies, and after tumor resection using full tumor tissue material. This study explored the discordance of ER/PR/HER2 between tumor needle biopsies and full tumor resection material using real-world patient-level data from Dutch breast cancer patients.
METHODS: Pathology reports of 11,054 breast cancer patients were derived from PALGA (Dutch Pathology Registry). Discordance was calculated for multiple combinations of the ER/PR/HER2 receptor status. The influence of patient and tumor characteristics on the probability of having discordant test results was analyzed using multiple logistic regression models (separately for ER, PR and HER2).
RESULTS: For 1279 patients (14.4%), at least one of the receptors (ER/PR/HER2) was determined on both biopsy and tumor tissue material. The majority had concordant test results for ER (n = 916; 94.8%), PR (n = 1170; 86.7%), and HER2 (n = 881; 98.1%). Patients having an ER- and HER2-positive but PR-negative biopsy classification, BR grade III, and < 10% tumor tissue remaining after neoadjuvant therapy (NAT) have the highest probability of ER discordant test results (OR 4.991; p = 83.31%). The probability of discordance in PR is based on different sets of patient and tumor characteristics. Potential cost savings from omitting multiple tests if concordance can be perfectly predicted can be up to €205,000 yearly.
CONCLUSIONS: Double testing of ER/PR/HER2 is less common than expected. Discordance in ER/PR/HER2 test results between tumor needle biopsy taken at the time of diagnosis and tumor resection material is very low, especially in patients not receiving any form of neoadjuvant therapy. These results imply that a substantial number of tests can potentially be omitted in specific subgroups of breast cancer patients.

PMID: 30756285 [PubMed - as supplied by publisher]

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Significance of baseline neutrophil-to-lymphocyte ratio for progression-free survival of patients with HER2-positive breast cancer treated with trastuzumab emtansine.

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Significance of baseline neutrophil-to-lymphocyte ratio for progression-free survival of patients with HER2-positive breast cancer treated with trastuzumab emtansine.

Sci Rep. 2019 Feb 12;9(1):1811

Authors: Imamura M, Morimoto T, Egawa C, Fukui R, Bun A, Ozawa H, Miyagawa Y, Fujimoto Y, Higuchi T, Miyoshi Y

Abstract
The efficacy of trastuzumab emtansine (T-DM1) is prolonged for some patients; however, the predictive factors remain unknown. We focused on a peripheral blood biomarker, the neutrophil-to-lymphocyte ratio (NLR), regarding T-DM1 treatment efficacy. Fifty-three advanced or metastatic breast cancers treated with T-DM1 were retrospectively recruited from three institutes. The NLR in the peripheral blood was measured at baseline and after one cycle. The cutoff value of the NLR was set at median value 2.56. The progression-free survival (PFS) of patients with NLR-low at baseline (n = 26; median, not reached) was significantly better than that of patients with NLR-high (n = 27; median, 4.13 months; hazard ratio [HR], 0.226; 95% confidence interval [CI], 0.112-0.493; p = 0.0001). Longer overall survival was significantly associated with a low NLR (HR, 0.384; 95% CI, 0.170-0.910; p = 0.0296). In the subgroup analysis, patients with NLR-low consistently had longer PFS compared to those with NLR-high irrespective of the number of prior chemotherapy regimens, prior trastuzumab, visceral metastasis, estrogen receptor status, and human epidermal growth factor receptor 2 (HER2) score. Although detailed mechanisms remain unknown, treatment efficacy of T-DM1 may be partly mediated by activation of the immune system. Low baseline NLR appears to be beneficial for treatment with T-DM1 in HER2-positive breast cancers.

PMID: 30755651 [PubMed - in process]

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In Appreciation of the Maternal and Child Health Journal’s Peer Reviewers, 2018

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Anterior Dor or Posterior Toupet with Heller Myotomy for Achalasia Cardia: A Systematic Review and Meta-Analysis.

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Anterior Dor or Posterior Toupet with Heller Myotomy for Achalasia Cardia: A Systematic Review and Meta-Analysis.

World J Surg. 2019 Feb 12;:

Authors: Siddaiah-Subramanya M, Yunus RM, Khan S, Memon B, Memon MA

Abstract
BACKGROUND AND AIMS: Partial fundoplication is commonly performed in conjunction with Heller Myotomy. It is, however, controversial whether anterior Dor or posterior Toupet partial fundoplication is the antireflux procedure of choice. The aim was to perform a systematic review and meta-analysis of studies comparing these two procedures.
MATERIAL AND METHODS: A search of PubMed, Cochrane database, Medline, Embase, Science Citation Index, Google scholar and current contents for English language articles comparing Dor and Toupet fundoplication following HM between 1991 and 2018 was performed. The outcome variables analyzed included operating time, length of hospital stay (LOHS), overall complication rate, quality of life (QOL), postoperative reflux, residual postoperative dysphagia, treatment failure and reoperations. The meta-analysis was prepared in accordance with the PRISMA-P statement.
RESULTS: Seven studies totaling 486 patients (Dor = 245, Toupet = 241) were analyzed. LOHS was significantly shorter for Toupet repair compared to Dor procedure (WMD 0.73, 95% CI 0.47 to 0.99; P < 0.0001). Furthermore, patients after Toupet experienced significantly better QOL than those after Dor (WMD 1.68, 95% CI 0.68 to 2.73, P < 0.001). All other variables showed comparable effects for these two procedures.
CONCLUSION: Our systematic review and meta-analysis revealed that Toupet fundoplication is superior to Dor in terms of LOHS and QOL following HM. For other variables such as postoperative reflux, postoperative dysphagia, complication rates and treatment failure, both Dor and Toupet fundoplication produced effective and equivalent results.

PMID: 30756164 [PubMed - as supplied by publisher]

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Revisiting Laparoscopic Reconstruction for Billroth 1 Versus Billroth 2 Versus Roux-en-Y After Distal Gastrectomy: A Systematic Review and Meta-Analysis in the Modern Era.

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Revisiting Laparoscopic Reconstruction for Billroth 1 Versus Billroth 2 Versus Roux-en-Y After Distal Gastrectomy: A Systematic Review and Meta-Analysis in the Modern Era.

World J Surg. 2019 Feb 12;:

Authors: Kim MS, Kwon Y, Park EP, An L, Park H, Park S

Abstract
BACKGROUND: In this modern era, laparoscopic distal gastrectomy (LDG) has largely replaced open distal gastrectomy for the treatment of gastric cancer; however, a quantitative review of reconstruction methods applied exclusively using LDG has not yet been published. Thereafter, we compared three reconstruction methods (Billroth I, Billroth II, and Roux-en Y) using the data derived solely from LDG patients.
METHODS: A systematic search was conducted using electronic bibliographic databases (Google Scholar, PubMed, and Embase), for articles that compared reconstruction methods in LDG, published within the last decade. A systematic review comparing 12 outcome parameters and sensitivity analyses were performed to increase the statistical power and minimize the inconsistency and heterogeneity of results.
RESULTS: Twenty-three clinical trials involving 5797 patients were included in the meta-analysis. There were no significant differences in the postoperative recovery and intraoperative parameters, except for operation time. B1 demonstrated a significantly shorter operation time when compared with B2 and RY by 21.6 min (P < 0.0001) and 44.69 min (P < 0.0001), respectively. In terms of postoperative endoscopic symptoms, RY was significantly superior to B1 and B2 for bile reflux (P < 0.001) and remnant gastritis (P < 0.001). For postoperative complications, B1 showed a significantly lower rate of postoperative morbidity than did RY and B2 (P = 0.0006 and P = 0.0005, respectively).
CONCLUSIONS: Our study is the first meta-analysis comparing anastomoses in LDG and introduces novel criteria for consideration when selecting reconstructions in LDG. Considering the significant differences in postoperative complications and endoscopic symptoms, these two parameters lay reasonable groundwork for guiding the surgeon's choice of reconstruction.

PMID: 30756163 [PubMed - as supplied by publisher]

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Nationwide Propensity-Score Matched Study of Mesh Versus Suture Repair of Primary Ventral Hernias in Women with a Subsequent Pregnancy.

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Nationwide Propensity-Score Matched Study of Mesh Versus Suture Repair of Primary Ventral Hernias in Women with a Subsequent Pregnancy.

World J Surg. 2019 Feb 12;:

Authors: Oma E, Bisgaard T, Jorgensen LN, Jensen KK

Abstract
BACKGROUND: Mesh reinforcement is recommended for repair of primary ventral hernias; however, this recommendation does not consider a potential subsequent pregnancy. The aim of this prospective cohort study was to compare mesh and suture repair of a primary ventral hernia in women with a subsequent pregnancy.
METHODS: All women of childbearing age who underwent repair of a primary ventral hernia between 2007 and 2014 were identified in the Danish Ventral Hernia Database. Data were merged with the Danish Medical Birth Registry. Women with a subsequent pregnancy and a propensity-score matched control group of women without a subsequent pregnancy were included. A structured questionnaire was sent out, and the primary outcome was hernia recurrence, while the secondary outcome was chronic postoperative pain.
RESULTS: In total, 632 women were included, of whom 441 (69.8%) responded to the questionnaire (195 and 246 with and without subsequent pregnancy, respectively). The 8-year cumulative incidence of recurrence was 24.8%. In women with a subsequent pregnancy, mesh repair was associated with a decreased risk of recurrence (hazard ratio 0.44, 95% CI 0.20-0.95, p = 0.038, number needed to treat = 5.1) and an increased risk of chronic pain (OR 5.07, 95% CI 1.20-23.38, p = 0.029, number needed to harm = 4.7) compared with suture repair, in multivariable analyses.
CONCLUSIONS: Mesh repair was associated with a decreased risk of recurrence, but an increased risk of chronic pain, compared with suture repair in women with a subsequent pregnancy.

PMID: 30756162 [PubMed - as supplied by publisher]

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Genotoxic response and damage recovery of macrophages to graphene quantum dots.

Genotoxic response and damage recovery of macrophages to graphene quantum dots.

Sci Total Environ. 2019 Jan 28;664:536-545

Authors: Xu L, Zhao J, Wang Z

Abstract
The potential adverse effects of graphene quantum dots (GQDs) have increasingly attracted attention. Our present study revealed the genotoxic responses of rat alveolar macrophages (NR8383) to aminated graphene QDs (AG-QDs) and detected the cellular recovery after removing AG-QDs. Global gene expression analysis from RNA-sequencing showed that AG-QDs (100 μg/mL) caused significant alterations in expression of 2898 genes after exposure for 24 h. Among these, 1335 and 1563 genes were up-regulated and down-regulated, respectively. Based on the Gene Ontology (GO) and Kyoto Encyclopedia of Gene and Genomes (KEGG) analysis, we found that most of the down-regulated genes were responsive to "cell cycle", which correlated well with the cell cycle arrest data that AG-QDs triggered cell cycle arrest at S (synthesis) and G2/M (second gap/mitosis) phase. The percentages of cells in S and G2/M phase were increased by 4.5%, and 29.0%, respectively. In addition, the up-regulated genes related with "endocytosis" and "phagocytosis" were identified, which could regulate the internalization of AG-QDs by endocytosis and phagocytosis. After removing exposed AG-QDs and re-incubating the cells in fresh medium, the arrest of S and G2/M phase in NR8383 cells was reduced, and the cell cycle gradually recovered. This cellular recovery could be attributed to the cellular excretion of AG-QDs and the up-regulation of the DNA-repair-related genes (Rad51, Brca2, and Atm). The current work provides insights into the potential hazards of AG-QDs in transcriptional level and presented the long-term effects of AG-QDs on organisms in environment.

PMID: 30759415 [PubMed - as supplied by publisher]

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Apoptosis and Cell Cycle Arrest of Hepatocellular Carcinoma Spheroids Treated by an Alternating Electric Field.

Apoptosis and Cell Cycle Arrest of Hepatocellular Carcinoma Spheroids Treated by an Alternating Electric Field.

Biotechnol Prog. 2019 Feb 13;:e2787

Authors: Huang CH, Lei KF, Tsang NM

Abstract
Most of the current cancer therapies may induce serious side effects and affect patient quality of life. Recently, a novel treatment using an alternating low-intensity and intermediate-frequency electric field was proposed and found to be a noninvasive and minimally toxic approach. However, additional fundamental studies and scientific evidence are required to further support the development of this treatment into a standard cancer therapy. In the current work, an in-house fabricated culture plate was developed to study the responses of hepatocellular carcinoma spheroids to treatment with an alternating electric field. From the results of the viability study, the electric field was confirmed to influence the dividing cells in the spheroids. Fluorescent staining of live and dead cells revealed that a fraction of the cells were damaged in the field-treated spheroids. Moreover, flow cytometry analyses were conducted and showed that a fraction of the cells in the spheroids underwent apoptosis and cell cycle arrest. Additionally, the apoptosis pathway (Bax/caspase) and cell cycle arrest pathway (p53/p21) were found to be activated after exposure to the electric field. In summary, the results further elucidated the cellular and molecular mechanism inducing apoptosis and cell cycle arrest in the field-treated hepatocellular carcinoma spheroids. This study provides more evidence to support the efficacy of electric-field-based cancer therapy. This article is protected by copyright. All rights reserved.

PMID: 30758916 [PubMed - as supplied by publisher]

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Transient Gene Expression Using Valproic Acid in Combination with Co-transfection of SV40 Large T Antigen and human p21CIP /p27KIP.

Transient Gene Expression Using Valproic Acid in Combination with Co-transfection of SV40 Large T Antigen and human p21CIP /p27KIP.

Biotechnol Prog. 2019 Feb 13;:

Authors: Kiszel P, Fiesel S, Voit S, Waechtler B, Meier T, Oelschlaegel T, Schraeml M, Engel AM

Abstract
Transient gene expression (TGE) in HEK293 cells was optimized by Vink et al. by co-expression of human cell cycle inhibitors p21CIP /p27KIP and SV40 virus large T antigen (SVLT). In this study, we investigated the effect of this enhancer protein complex on the TGE experiments in a cell-cycle arrested condition of HEK293F cells induced by valproic acid (VPA). Growth profiles, consumptions of nutrients, formations of waste products and product titers of recombinant human antibodies (huAb) were monitored during the 7-day cultivation time. Our results showed that the use of enhancer proteins increased the product yields in a growth arrest condition as well. During the growth phase, no differences were detected regarding viable cell densities (VCD), viabilities, growth rates and cell diameters between the TGE experiments with and without enhancer proteins. However, during the declining phase VCD and viability showed slightly higher values at day 6 and 7 in the presence of enhancers. Furthermore, we could not detect any differences in glucose and glutamine metabolism during batch cultivations with co-expression of enhancer proteins. Taken together, the special complex of enhancer proteins did not contribute to further enhancement of growth arrest and shift in the main cell metabolisms, but resulted in higher cell viability during the decline phase. Our observations suggest that the human cell cycle inhibitors p21CIP /p27KIP together with very low amount of SVLT antigen may induce alternative functional activities than growth arrest to further improve the yield of recombinant proteins. This article is protected by copyright. All rights reserved.

PMID: 30758913 [PubMed - as supplied by publisher]

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PROTACs suppression of CDK4/6, crucial kinases for cell cycle regulation in cancer.

PROTACs suppression of CDK4/6, crucial kinases for cell cycle regulation in cancer.

Chem Commun (Camb). 2019 Feb 13;:

Authors: Zhao B, Burgess K

Abstract
PROTACs based on two selective, FDA approved, CDK4/6 inhibitors were formed. One of them, based on palbociclib, potently initiates degradation of these CDK proteins, and suppresses phosphorylation of retinoblastoma protein (Rb) leading to cell cycle arrest. These PROTACs are active at nanomolar concentrations, and appear to be the first for CDK4/6.

PMID: 30758029 [PubMed - as supplied by publisher]

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A p53-stabilizing agent, CP-31398, induces p21 expression with increased G2/M phase through the YY1 transcription factor in esophageal carcinoma defective of the p53 pathway.

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A p53-stabilizing agent, CP-31398, induces p21 expression with increased G2/M phase through the YY1 transcription factor in esophageal carcinoma defective of the p53 pathway.

Am J Cancer Res. 2019;9(1):79-93

Authors: Zhong B, Shingyoji M, Hanazono M, Nguyễn TTT, Morinaga T, Tada Y, Hiroshima K, Shimada H, Tagawa M

Abstract
Restoration of p53 functions is one of the therapeutic strategies for esophageal carcinoma which is often defective of the p53 pathway. We examined effects of CP-31398 which potentially increased expression of wild-type p53 or converted mutated p53 to the wild-type. We used 9 kinds of human squamous esophageal carcinoma cells with different p53 genotypes and examined expression of p53 and the related molecules in CP-31398-treated cells. Cisplatin, a DNA damaging agent, induced cleavages of PARP and caspase-3 without increase of p53 levels, indicating that the p53 down-stream pathway was disrupted in these cells. CP-31398 induced growth retardation but the cytotoxic effects were irrelevant to p53 genotype. CP-31398 influenced expression of p53 and the downstream molecules in a cell-dependent manner, but constantly increased p21 expression at the transcriptional level with decreased YY1 expression. Knockdown experiments with siRNA demonstrated that the CP-31398-mediated p21 up-regulation was unrelated with p53 expression but was associated with YY1 expression. We also showed that CP-31398-induced cell cycle changes including increase of G2/M populations was attributable to the up-regulated p21. These data collectively indicated that CP-31398 augmented endogenous p21 levels and induced cell cycle changes through regulation of YY1, and that YY1 was a novel target of CP-31398 in p53 dysfunctional cells.

PMID: 30755813 [PubMed]

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Long-Term Transcriptional Activity at Zero Growth of a Cosmopolitan Rare Biosphere Member.

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Long-Term Transcriptional Activity at Zero Growth of a Cosmopolitan Rare Biosphere Member.

MBio. 2019 Feb 12;10(1):

Authors: Hausmann B, Pelikan C, Rattei T, Loy A, Pester M

Abstract
Microbial diversity in the environment is mainly concealed within the rare biosphere (all species with <0.1% relative abundance). While dormancy explains a low-abundance state very well, the mechanisms leading to rare but active microorganisms remain elusive. We used environmental systems biology to genomically and transcriptionally characterize "Candidatus Desulfosporosinus infrequens," a low-abundance sulfate-reducing microorganism cosmopolitan to freshwater wetlands, where it contributes to cryptic sulfur cycling. We obtained its near-complete genome by metagenomics of acidic peat soil. In addition, we analyzed anoxic peat soil incubated under in situ-like conditions for 50 days by Desulfosporosinus-targeted qPCR and metatranscriptomics. The Desulfosporosinus population stayed at a constant low abundance under all incubation conditions, averaging 1.2 × 106 16S rRNA gene copies per cm³ soil. In contrast, transcriptional activity of "Ca. Desulfosporosinus infrequens" increased at day 36 by 56- to 188-fold when minor amendments of acetate, propionate, lactate, or butyrate were provided with sulfate, compared to the no-substrate-control. Overall transcriptional activity was driven by expression of genes encoding ribosomal proteins, energy metabolism, and stress response but not by expression of genes encoding cell growth-associated processes. Since our results did not support growth of these highly active microorganisms in terms of biomass increase or cell division, they had to invest their sole energy for maintenance, most likely counterbalancing acidic pH conditions. This finding explains how a rare biosphere member can contribute to a biogeochemically relevant process while remaining in a zero-growth state over a period of 50 days.IMPORTANCE The microbial rare biosphere represents the largest pool of biodiversity on Earth and constitutes, in sum of all its members, a considerable part of a habitat's biomass. Dormancy or starvation is typically used to explain the persistence of low-abundance microorganisms in the environment. We show that a low-abundance microorganism can be highly transcriptionally active while remaining in a zero-growth state for at least 7 weeks. Our results provide evidence that this zero growth at a high cellular activity state is driven by maintenance requirements. We show that this is true for a microbial keystone species, in particular a cosmopolitan but permanently low-abundance sulfate-reducing microorganism in wetlands that is involved in counterbalancing greenhouse gas emissions. In summary, our results provide an important step forward in understanding time-resolved activities of rare biosphere members relevant for ecosystem functions.

PMID: 30755506 [PubMed - in process]

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Metformin Treatment Suppresses Melanoma Cell Growth and Motility Through Modulation of microRNA Expression.

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Metformin Treatment Suppresses Melanoma Cell Growth and Motility Through Modulation of microRNA Expression.

Cancers (Basel). 2019 Feb 11;11(2):

Authors: Tseng HW, Li SC, Tsai KW

Abstract
Melanoma is a highly aggressive cancer with high mortality in advanced stages.Metformin is an oral biguanide drug used for diabetes and has demonstrated positive effects oncancer prevention and treatment. Herein, we found that metformin significantly suppressedmelanoma cancer cell motility and growth through inducing cell cycle arrest at the G2/M phase andpromoting cell apoptosis. Using the next-generation sequencing approach, we identified threeupregulated microRNAs (miRNA; miR-192-5p, miR-584-3p, and miR-1246) in melanoma cellstreated with metformin. Among these, we examined the roles of miR-192-5p and miR-584-3p anddiscovered that they significantly suppressed melanoma cell motility. Furthermore, they inhibitedmelanoma cell growth through destroying cell cycle progression and inducing cell apoptosis. Usingmicroarray and bioinformatics approaches for identifying putative target genes, Epidermal growthfactor (EGF) containing fibulin-like extracellular matrix protein 1 (EFEMP1) gene for miR-192-5pand an isoform of the secretory carrier membrane proteins (SCAMP3) gene for miR-584-3p could besilenced through targeting their 3'UTR region directly. EFEMP1 and SCAMP3 knockdownsignificantly suppressed melanoma cell growth, but only EFEMP1 knockdown inhibited its motilityabilities. Our findings indicated that miR-192-5p and miR-584-3p might contribute to metformininducedgrowth and motility suppression in melanoma cells through silencing their target genesEFEMP1 and SCAMP3.

PMID: 30754729 [PubMed]

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C/EBPβ Is a Transcriptional Regulator of Wee1 at the G₂/M Phase of the Cell Cycle.

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C/EBPβ Is a Transcriptional Regulator of Wee1 at the G₂/M Phase of the Cell Cycle.

Cells. 2019 Feb 11;8(2):

Authors: Lee JH, Sung JY, Choi EK, Yoon HK, Kang BR, Hong EK, Park BK, Kim YN, Rho SB, Yoon K

Abstract
The CCAAT/enhancer-binding protein β (C/EBPβ) is a transcription factor that regulates cellular proliferation, differentiation, apoptosis and tumorigenesis. Although the pro-oncogenic roles of C/EBPβ have been implicated in various human cancers, how it contributes to tumorigenesis or tumor progression has not been determined. Immunohistochemistry with human non-small cell lung cancer (NSCLC) tissues revealed that higher levels of C/EBPβ protein were expressed compared to normal lung tissues. Knockdown of C/EBPβ by siRNA reduced the proliferative capacity of NSCLC cells by delaying the G₂/M transition in the cell cycle. In C/EBPβ-knockdown cells, a prolonged increase in phosphorylation of cyclin dependent kinase 1 at tyrosine 15 (Y15-pCDK1) was displayed with simultaneously increased Wee1 and decreased Cdc25B expression. Chromatin immunoprecipitation (ChIP) analysis showed that C/EBPβ bound to distal promoter regions of WEE1 and repressed WEE1 transcription through its interaction with histone deacetylase 2. Treatment of C/EBPβ-knockdown cells with a Wee1 inhibitor induced a decrease in Y15-pCDK1 and recovered cells from G₂/M arrest. In the xenograft tumors, the depletion of C/EBPβ significantly reduced tumor growth. Taken together, these results indicate that Wee1 is a novel transcription target of C/EBPβ that is required for the G₂/M phase of cell cycle progression, ultimately regulating proliferation of NSCLC cells.

PMID: 30754676 [PubMed]

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Abnormal Expression of c-Myc Oncogene in NK Cells in Patients with Cancer.

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Abnormal Expression of c-Myc Oncogene in NK Cells in Patients with Cancer.

Int J Mol Sci. 2019 Feb 11;20(3):

Authors: Zakiryanova GK, Kustova E, Urazalieva NT, Baimuchametov ET, Nakisbekov NN, Shurin MR

Abstract
Natural killer (NK) cells have received a lot of attention in recent years for the roles they play in immunity and particularly in antitumor immune responses. Although defects in NK cell functions are recognized as important mechanisms for immune evasion of malignant cells, molecular pathways regulating NK cell dysfunction and exhaustion in cancer are largely unknown. Here we tested whether the c-myc proto-oncogene, known to promote cell proliferation, growth, differentiation, and apoptosis by regulating the expression of numerous target genes, may be involved in the mechanism of NK cell abnormalities in patients with lung and gastric cancer. Analysis of c-myc mRNA and protein expression in peripheral blood NK cells, mitogen-activated protein kinase (MAPK) activity, cell cycle, and cell longevity revealed a significantly decreased expression of c-myc mRNA and protein and mitotic arrest of NK cells in different phases of cell cycle. In addition, a significant decrease of NK cell death was also detected. These data allow the suggestion that defects of NK cell-mediated tumor surveillance may be associated with disturbed c-myc expression in NK cells in cancer patients. A better understanding of the mechanisms of NK cell dysfunction in cancer will help in the NK cell-mediated therapeutic eradication of primary and metastatic cancer cells and prolong patient survival.

PMID: 30754645 [PubMed - in process]

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Nanoformulation of a Novel Pyrano[2,3-c] Pyrazole Heterocyclic Compound AMDPC Exhibits Anti-Cancer Activity via Blocking the Cell Cycle through a P53-Independent Pathway.

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Nanoformulation of a Novel Pyrano[2,3-c] Pyrazole Heterocyclic Compound AMDPC Exhibits Anti-Cancer Activity via Blocking the Cell Cycle through a P53-Independent Pathway.

Molecules. 2019 Feb 11;24(3):

Authors: Sun X, Zhang L, Gao M, Que X, Zhou C, Zhu D, Cai Y

Abstract
Pyrano[2,3-c]pyrazole derivatives have been reported as exerting various biological activities. One compound with potential anti-tumor activity was screened out by MTT assay from series of dihydropyrazopyrazole derivatives we had synthesized before using a one-pot, four-component reaction, and was named as 6-amino-4-(2-hydroxyphenyl)-3-methyl-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile (hereinafter abbreviated as AMDPC). The IC50 of AMDPC against Bcap-37 breast cancer cells was 46.52 μg/mL. Then the hydrophobic AMDPC was encapsulated in PEG-PLGA block copolymers, and then self-assembled as polymeric micelle (mPEG-PLGA/AMDPC) to improve both physiochemical and release profiles. The effect of mPEG-PLGA/AMDPC on BCAP-37 cancer cells showed similar anti-tumor effects as AMDPC. Furthermore, the anti-tumor mechanism of mPEG-PLGA/AMDPC was investigated, which can probably be attributed to stimulating the expression of P21 gene and therefore protein production on BCAP-37 cells, and then blocked the cell cycle through the P53-independent pathway both in S phase and G2 phase. Thus, mPEG-PLGA/AMDPC is a promising therapeutic agent for cancer treatment, and further in vivo studies will be developed.

PMID: 30754632 [PubMed - in process]

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Differential expression of vitamin D associated genes in the aorta of coronary artery disease patients with and without rheumatoid arthritis.

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Differential expression of vitamin D associated genes in the aorta of coronary artery disease patients with and without rheumatoid arthritis.

PLoS One. 2018;13(8):e0202346

Authors: Oma I, Olstad OK, Andersen JK, Lyberg T, Molberg Ø, Fostad I, Wang Fagerland M, Almdahl SM, Rynning SE, Yndestad A, Aukrust P, Whist JE, Hollan I

Abstract
BACKGROUND: Vitamin D has an important role in the immune system, and has been linked to rheumatoid arthritis (RA) and coronary artery disease (CAD). The exact mechanisms by which vitamin D is involved in these processes are still unclear. Therefore, we wanted to search for differences in expression of genes involved in the vitamin D receptor (VDR) activation pathway and genes that are known to alter upon vitamin D stimulation, in the aortic adventitia of CAD patients with and without RA.
METHODS: Affymetrix microarray was used to determine gene expression profile in surgical specimens from the adventitia of the ascending aorta of CAD patients with RA (n = 8) and without RA (n = 8) from the Feiring Heart Biopsy Study.
RESULTS: We identified three vitamin D associated genes that were differentially expressed between RA and non-RA patients: Growth arrest and DNA-damage-inducible protein 45 alpha (GADD45A) (FC = 1.47; p = 0.006), Nuclear Receptor Co-repressor 1 (NCOR1) (FC = 1,21; p = 0.005) and paraoxonases 2 (PON2) (FC = -1.37; p = 0.01). High expression of GADD45A in RA tissues was confirmed by real-time qRT-PCR. GADD45A expression correlated with plasma levels of 1,25(OH)2D3 (rs = 0.69; p = 0.003).
CONCLUSIONS: Microarray analyses revealed higher expression of GADD45A and NCOR1; and lower expression of PON2 in the aortic adventitia of RA than non-RA patients. Further studies are needed to elucidate if and how GADD45A, NCOR1 and PON2 are involved in the development of accelerated atherosclerosis in RA. In theory, some of these factors might have proatherogenic effects whereas others might reflect an underlying vascular pathology promoting atherogenesis (such as vascular stress).

PMID: 30138371 [PubMed - indexed for MEDLINE]

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