The Thioredoxin-Like Family of Selenoproteins: Implications in Aging and Age-Related Degeneration

Abstract

The thioredoxin-like (Rdx) family proteins contain four selenoproteins (selenoprotein H, SELENOH; selenoprotein T, SELENOT; selenoprotein V, SELENOV; selenoprotein W, SELENOW) and a nonselenoprotein Rdx12. They share a CxxU or a CxxC (C, cysteine; x, any amino acid; U, selenocysteine) motif and a stretch of eGxFEI(V) sequence. From the evolutionary perspective, SELENOW and SELENOV are clustered together and SELENOH and SELENOT are in another branch. Selenoproteins in the Rdx family exhibit tissue- and organelle-specific distribution and are differentially influenced in response to selenium deficiency. While SELENOH is nucleus-exclusive, SELENOT resides mainly in endoplasmic reticulum and SELENOW in cytosol. SELENOV is expressed essentially only in the testes with unknown cellular localization. SELENOH and SELENOW are more sensitive than SELENOT and SELENOV to selenium deficiency. While physiological functions of the Rdx family of selenoproteins are not fully understand, results from animal models demonstrated that (1) brain-specific SELENOT knockout mice are susceptible to 1-methyl-4-phenylpyridinium-induced Parkinson's disease in association with redox imbalance and (2) adult zebrafishes with heterozygous SELENOH knockout are prone to dimethylbenzanthracene-induced tumorigenesis together with increased DNA damage and oxidative stress. Further animal and human studies are needed to fully understand physiological roles of the Rdx family of selenoproteins in redox regulation, genome maintenance, aging, and age-related degeneration.

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The Impact of Trace Minerals on Bone Metabolism

Abstract

Bone is a metabolically active tissue that responds to alterations in dietary intake and nutritional status. It is ~ 35% protein, mostly collagen which provides an organic scaffolding for bone mineral. The mineral is the remaining ~ 65% of bone tissue and composed mostly of calcium and phosphate in a form that is structurally similar to mineral within the apatite group. The skeletal tissue is constantly undergoing turnover through resorption by osteoclasts coupled with formation by osteoblasts. In this regard, the overall bone balance is determined by the relative contribution of each of these processes. In addition to macro minerals such as calcium, phosphorus, and magnesium which have well-known roles in bone health, trace elements such as boron, iron, zinc, copper, and selenium also impact bone metabolism. Effects of trace elements on skeletal metabolism and tissue properties may be indirect through regulation of macro mineral metabolism, or direct by affecting osteoblast or osteoclast proliferation or activity, or finally through incorporation into the bone mineral matrix. This review focuses on the skeletal impact of the following trace elements: boron, iron, zinc, copper, and selenium, and overviews the state of the evidence for each of these minerals.

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Systematic Review of the Effects of Chromium(III) on Chickens

Abstract

Chromium supplementation has been proposed to have beneficial effects in farm animals, particularly when under stress. The last two decades, in particular, have seen an emphasis on examining the effects of supplemental chromium on a variety of variables in chicks and chickens. Thus, given the recent approval of a Cr(III) compound for use in chicken feed in the United States and the recent surge in papers on the use of Cr in chicken feed, the need for a systematic review of studies utilizing chickens is extremely urgent and timely. With the exception of studies on cold-stressed laying hens, the results of studies of Cr supplementation of chickens, whether broilers or laying hens, were found to be too inconsistent for any firm conclusions to be drawn other than that Cr supplementation generally leads to accumulation of Cr in tissues. Few potential trends in terms or beneficial or deleterious effects from Cr supplementation were found regardless of strain of chicken, Cr source, Cr dose, duration of supplementation, or variable examined. Hence, in summary, no recommendation for the use of Cr as a supplement for the diet of chickens can be made at this time.

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Iodine Nutrition During Pregnancy: Past, Present, and Future

Abstract

Iodine is a trace element that is important for the synthesis of thyroid hormones. During pregnancy, iodine requirements are increased by approximately 50% because of physiological changes. Adequate iodine status in pregnancy is crucial for maternal health and fetal growth. The World Health Organization (WHO) recommends a daily intake of 250 μg iodine for pregnant women to maintain adequate iodine status. Severe iodine deficiency during pregnancy can result in a series of detrimental effects on maternal and fetal health including hypothyroidism, goiter, stillbirth, abortion, increased neonatal mortality, neurological damage, and intellectual impairment. Correction of severe iodine deficiency can reduce the risk of adverse impacts. However, the influences of mild-to-moderate maternal iodine deficiency on fetal neural development and cognitive function are less clear. The safety and efficacy of iodine supplementation in mildly-to-moderately iodine-deficient women also remain uncertain. In addition, excess iodine during pregnancy carries a risk of adverse effects, and the recommended safe upper limits of iodine intake are controversial. Effective iodine supplementation should be implemented, and routine monitoring is necessary to guarantee adequate iodine status.

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Vanadium in Biological Action: Chemical, Pharmacological Aspects, and Metabolic Implications in Diabetes Mellitus

Abstract

Vanadium compounds have been primarily investigated as potential therapeutic agents for the treatment of various major health issues, including cancer, atherosclerosis, and diabetes. The translation of vanadium-based compounds into clinical trials and ultimately into disease treatments remains hampered by the absence of a basic pharmacological and metabolic comprehension of such compounds. In this review, we examine the development of vanadium-containing compounds in biological systems regarding the role of the physiological environment, dosage, intracellular interactions, metabolic transformations, modulation of signaling pathways, toxicology, and transport and tissue distribution as well as therapeutic implications. From our point of view, the toxicological and pharmacological aspects in animal models and humans are not understood completely, and thus, we introduced them in a physiological environment and dosage context. Different transport proteins in blood plasma and mechanistic transport determinants are discussed. Furthermore, an overview of different vanadium species and the role of physiological factors (i.e., pH, redox conditions, concentration, and so on) are considered. Mechanistic specifications about different signaling pathways are discussed, particularly the phosphatases and kinases that are modulated dynamically by vanadium compounds because until now, the focus only has been on protein tyrosine phosphatase 1B as a vanadium target. Particular emphasis is laid on the therapeutic ability of vanadium-based compounds and their role for the treatment of diabetes mellitus, specifically on that of vanadate- and polioxovanadate-containing compounds. We aim at shedding light on the prevailing gaps between primary scientific data and information from animal models and human studies.

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Iron, Zinc, and Physical Performance

Abstract

Iron and zinc are nutritionally essential trace elements that function through incorporation into proteins and enzymes; many of these proteins and enzymes affect physical performance. Poor iron status (iron deficiency and iron deficiency anemia) is prevalent in both developed and developing nations. Zinc deficiency has been reported in clinical and population studies, although the incidence is difficult to quantify due to the lack of a reliable zinc status indicator. The objective of this manuscript is to review the relationship between iron and zinc status and physical performance. In sum, numerous reports indicate diminished physical performance in individuals with poor iron and/or zinc status, whereas, in individuals with adequate status, evidence supporting a beneficial role of iron or zinc at levels beyond the recommended dietary allowance for optimizing physical performance is lacking.

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Editorial

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Effects of Nutritional Deficiency of Boron on the Bones of the Appendicular Skeleton of Mice

Abstract

Scientific evidence has shown the nutritional importance of boron (B) in the remodeling and repair of cancellous bone tissue. However, the effects of the nutritional deficiency of B on the cortical bone tissue of the appendicular skeleton have not yet been described. Thus, a study was performed to histomorphometrically evaluate the density of osteocyte lacunae of cortical bone of mouse femora under conditions of nutritional deficiency of B and to analyze the effects of the deficiency on the biomechanical properties of mouse tibiae. Weaning, 21-day-old male Swiss mice were assigned to the following two groups: controls (B+; n = 10) and experimental (B−; n = 10). Control mice were fed a basal diet containing 3 mg B/kg, whereas experimental mice were fed a B-deficient diet containing 0.07 mg B/kg for 9 weeks. The histological and histomorphometric evaluations of the mice fed a B-deficient diet showed a decrease in the density of osteocyte lacunae in the femoral cortical bone tissue and the evaluation of biomechanical properties showed lower bone rigidity in the tibia.

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Hair Mineral and Trace Element Content in Children with Down’s Syndrome

Abstract

The objective of the present study was to assess the level of minerals and trace elements in 40 children with Down's syndrome and 40 controls aged 1–2 years old. Hair mineral and trace element analysis was performed using inductively coupled plasma mass spectrometry. The obtained data demonstrate that hair levels of Mg, P, I, Cr, Si, Zn, and Pb in Down's syndrome patients exceeded the respective control values by 36, 36, 93, 57, 45, 28, and 54%, whereas hair mercury was more than twofold lower in children with Down's syndrome. The observed difference in the levels of trace elements was age-dependent. In particular, in 1-year-olds, major differences were observed for essential elements (Cr, Si, Zn), whereas in 2-year-olds—for toxic elements (Hg, Pb). At the same time, hair P levels in Down's syndrome patients were 14 and 35% higher at the age of 1 and 2 years in comparison to the respective controls. Multiple regression analysis demonstrated that a model incorporating all elements, being characterized by a significant group difference, accounted for 42.5% of status variability. At the same time, only hair phosphorus was significantly interrelated with Down's syndrome status (β = 0.478; p < 0.001). Principal component analysis (PCA) used As, Ca, Cr, Fe, Hg, I, Mg, P, Pb, Se, Si, Sn, and Zn as predictors, with the resulting R² = 0.559. The OPLS-DA models also separated between Down's and health control groups. Therefore, 1–2-year-old patients with Down's syndrome are characterized by significant alterations of mineral and trace element status.

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The Problematic Use of Dietary Reference Intakes to Assess Magnesium Status and Clinical Importance

Abstract

Determination of the public health concern about magnesium (Mg) in health and disease has been confounded by the lack of a practical measure of status. This has resulted in a lack of consistency in associating Mg deficiency with specific pathological conditions. Some attempts at associating Mg with a chronic disease have used the Dietary Reference Intakes (DRIs) as a status assessment measure. Use of current DRIs for Mg is problematic because recent evidence suggests that they should be updated and based on body weight. An evidence-based suggested Estimated Average Requirement (EAR) and Recommended Dietary Allowance (RDA) for a 70-kg individual is 175 and 250 mg/day, respectively. However, numerous dietary and physiological factors can affect the need for Mg and thus affect the use of the current or suggested new DRIs to assess Mg status. Calcium intakes above normal requirements can decrease Mg balance and exacerbate signs of Mg deficiency. Mg deficiency apparently occurs often in obesity because of increased need to counteract the inflammatory stress induced by adipose tissue dysfunction. Deficiency in anti-oxidant nutrients such as vitamin E and selenium can exacerbate a response to low dietary Mg indicated by increased oxidative stress which can lead to chronic disease. Dietary modifiers of Mg absorption and excretion affect balance and thus the need for Mg. Factors decreasing Mg balance include low dietary protein and non-fermentable fiber, while factors that can increase balance include fructose and fermentable fiber and fructose-containing oligosaccharides. Use of the DRIs to assess the Mg status of a population or group needs to consider their physiological characteristics and dietary habits and be aware that the DRIs may need updating. The DRIs only can be considered a component of a toolbox that presently includes serum Mg concentration and the daily urinary Mg excretion to assess the Mg status of an individual.

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A Brief Overview from the Physiological and Detrimental Roles of Zinc Homeostasis via Zinc Transporters in the Heart

Abstract

Zinc (mostly as free/labile Zn²⁺) is an essential structural constituent of many proteins, including enzymes in cellular signaling pathways via functioning as an important signaling molecule in mammalian cells. In cardiomyocytes at resting condition, intracellular labile Zn²⁺ concentration ([Zn²⁺]_i) is in the nanomolar range, whereas it can increase dramatically under pathological conditions, including hyperglycemia, but the mechanisms that affect its subcellular redistribution is not clear. Therefore, overall, very little is known about the precise mechanisms controlling the intracellular distribution of labile Zn²⁺, particularly via Zn²⁺ transporters during cardiac function under both physiological and pathophysiological conditions. Literature data demonstrated that [Zn²⁺]_i homeostasis in mammalian cells is primarily coordinated by Zn²⁺ transporters classified as ZnTs (SLC30A) and ZIPs (SLC39A). To identify the molecular mechanisms of diverse functions of labile Zn²⁺ in the heart, the recent studies focused on the discovery of subcellular localization of these Zn²⁺ transporters in parallel to the discovery of novel physiological functions of [Zn²⁺]_i in cardiomyocytes. The present review summarizes the current understanding of the role of [Zn²⁺]_i changes in cardiomyocytes under pathological conditions, and under high [Zn²⁺]_i and how Zn²⁺ transporters are important for its subcellular redistribution. The emerging importance and the promise of some Zn²⁺ transporters for targeted cardiac therapy against pathological stimuli are also provided. Taken together, the review clearly outlines cellular control of cytosolic Zn²⁺ signaling by Zn²⁺ transporters, the role of Zn²⁺ transporters in heart function under hyperglycemia, the role of Zn²⁺ under increased oxidative stress and ER stress, and their roles in cancer are discussed.

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Boron, Chromium, Manganese, and Nickel in Agricultural Animal Production

Abstract

This paper provides an overview of research that has been conducted with manganese (Mn), chromium (Cr), nickel (Ni), and boron (B) in poultry, swine, and ruminants. Manganese is an essential trace mineral that functions as an enzyme component and enzyme activator. A deficiency of Mn results in a variety of bone abnormalities, and Mn deficiency signs have been observed under practical conditions in poultry and cattle. Chromium can potentiate the action of insulin, but whether Cr is an essential trace mineral is controversial. Insulin sensitivity has been enhanced by Cr in cattle, swine, and broilers. Responses to Cr supplementation have been variable. Production responses to Cr supplementation have been most consistent in animals exposed to various stressors (heat, cold, weaning, etc). The legality of supplementing Cr to animal diets varies among countries, Cr sources, and animal species. A specific biochemical function for Ni and B has not been identified in mammals. Signs of Ni deficiency have been produced experimentally in a number of animal species. Nickel may affect rumen microbial fermentation in ruminants, as Ni is a component of bacterial urease and cofactor F₄₃₀ in methanogenic bacteria. There is little evidence that dietary Ni limits animal production under practical conditions. Beneficial effects of B supplementation on growth and bone strength have been seen in poultry and swine, but results have been variable.

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Investigating the Essentiality and Requirements of Iron from the Ancient to the Present

Abstract

This review discusses the development of studies that evaluated the essentiality and requirements of iron from the ancient to the present. The therapeutic effects of iron compounds were recognized by the ancient Greeks and Romans. The earliest recognition of the essentiality of iron was stated by Paracelsus, a distinguished physician alchemist, in the sixteenth century. Iron was included in the earliest nutritional standard prepared for the Royal Army by E. A. Parkes, the first professor of hygiene. The League of Nations Health Organisation determined average iron requirements based on literature review. In the first US Recommended Dietary Allowances (RDA), the RDA of iron was determined from the results of iron balance studies. In the current Dietary Reference Intakes, iron requirements were determined based on the factorial method with the aid of Monte Carlo simulation for combining basal and menstrual iron losses. Population data analysis is a recently developed alternative that does not use the pre-estimated iron absorption rate and requires the prevalence of inadequacy instead. Population data analysis uses the convolution integral for combining basal and menstrual iron losses to ensure the required accuracy. This review also provides new estimates of hair and nail iron losses.

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Improved Magnesium Levels in Morbidly Obese Diabetic and Non-diabetic Patients After Modest Weight Loss

Abstract

Serum magnesium (Mg) is reported to be reduced in individuals with obesity, hypertension, and diabetes mellitus and has been suggested as a marker for metabolic syndrome. We have studied changes in serum Mg concentrations in a group of obese patients (n = 92) with and without diabetes mellitus after weight loss induced by dieting and bariatric surgery. At inclusion, 11% (10/92) of the population had severe Mg deficiency (< 0.75 mmol/L) and median serum Mg was lower in diabetic (n = 20) compared to non-diabetic (n = 72) patients (p = 0.002). A weight loss of 10 kg after 8 weeks of lifestyle interventions was accompanied by increased serum Mg of about 5% in both diabetic and non-diabetic patients. Serum Mg remained stable thereafter in the non-diabetic patients, while it continued to increase in the diabetic patients after bariatric surgery. Six months after bariatric surgery, there was no significant difference in serum Mg concentration between the groups (p = 0.08). The optimal range of circulating Mg concentration is not known, but as even small increments in serum Mg are reported to lower the risk of cardiovascular and ischemic heart disease, our results are interesting in a public health perspective.

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Small Molecule Modifiers of In Vitro Manganese Transport Alter Toxicity In Vivo

Abstract

Manganese (Mn) is essential for several species and daily requirements are commonly met by an adequate diet. Mn overload may cause motor and psychiatric disturbances and may arise from an impaired or not fully developed excretion system, transporter malfunction and/or exposure to excessive levels of Mn. Therefore, deciphering processes regulating neuronal Mn homeostasis is essential to understand the mechanisms of Mn neurotoxicity. In the present study, we selected two small molecules (with opposing effects on Mn transport) from a previous high throughput screen of 40,167 to test their effects on Mn toxicity parameters in vivo using Caenorhabditis elegans. We pre-exposed worms to VU0063088 and VU0026921 for 30 min followed by co-exposure for 1 h with Mn and evaluated Mn accumulation, dopaminergic (DAergic) degeneration and worm survival. Control worms were exposed to vehicle (DMSO) and saline only. In pdat-1::GFP worms, with GFP labeled DAergic neurons, we observed a decrease of Mn-induced DAergic degeneration in the presence of both small molecules. This effect was also observed in an smf-2 knockout strain. SMF-2 is a regulator of Mn transport in the worms and this strain accumulates higher Mn levels. We did not observe improved survival in the presence of small molecules. Our results suggest that both VU0063088 and VU0026921 may modulate Mn levels in the worms through a mechanism that does not require SMF-2 and induce protection against Mn neurotoxicity.

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Sources and distribution of arsenic in agricultural soils of Central Mexico

Abstract

Purpose

The concentrations and distribution of arsenic (As) in two different soil types (Vertisols and Entisols) of Central Mexico impacted by mine activities and irrigation with As-rich groundwater are analyzed in order to determine their impact on the soil quality, and to contribute reliable data that may help to assess the environmental risk that represents the progressive accumulation of As in the arable soils of Guanajuato.

Materials and methods

Two Entisol and two Vertisol profiles located in the Guanajuato state (Mexico) were described and sampled from ~ 1.20-m-deep pits. Soils are irrigated with As-rich deep and shallow groundwaters that were sampled from irrigation boreholes. Additionally, a Vertisol profile located in a parcel not impacted by irrigation was sampled and used as a control soil. Minerals were identified by X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with dispersive X-ray spectrometry (EDS). Geoaccumulation indexes (Igeo) were calculated to evaluate As enrichment with respect to a control soil and the Upper Continental Crust (UCC). Anions and cations of groundwater were analyzed by high-performance liquid chromatography (HPLC) and by inductively coupled plasma atomic emission spectroscopy (ICP-AES), respectively. As in soils was determined by ICP-AES.

Results and discussion

Near total As concentrations are higher in Entisols (mean As value = 7.20 mg/kg) than in Vertisols (mean As = 1.02 mg/kg). As concentrations in the control soil are lower (0.34 to 0.70 mg/kg). The in-depth distribution of As in Vertisol profiles reveals that the higher As concentrations are found in the uppermost horizons (10 cm) and they tend to decrease with depth. In Entisols, As concentrations do not follow a vertical trend. Igeo values of As indicate moderate to heavy As contamination in Vertisols and moderate contamination in Entisols. SEM-EDS analyses revealed the presence of some potential As-bearing minerals such as magnetite and abundant Fe oxides and Ti-Fe coatings precipitated onto feldspar grains, particularly in Entisols.

Conclusions

Irrigation of Vertisols with As-rich groundwater determines As concentrations in the uppermost horizons that exceed the natural background of the region (0.4 mg/kg). In depth, clay grain-sized particles inhibit the downward migration of As, while Fe oxides and organic matter scavenge As by adsorption. As concentrations in Entisols are higher, and the in-depth distribution of this element is controlled by periodic contributions of As-bearing minerals delivered from mine prospects located at the river's catchments.

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Comparing alternative tracing measurements and mixing models to fingerprint suspended sediment sources in a mesoscale Mediterranean catchment

Abstract

Purpose

Knowledge of suspended sediment provenance in mesoscale catchments is important for applying erosion control measures and best management practices as well as for understanding the processes controlling sediment transport in the critical zone. As suspended sediment fluxes are highly variable in time, particularly given the variability of soil and rainfall properties in mesoscale catchments, knowledge of sediment provenance at high temporal resolution is crucial.

Materials and methods

Suspended sediment fluxes were analyzed at the outlet of a 42-km² Mediterranean catchment belonging to the French critical zone observatory network (OZCAR). Spatial origins of the suspended sediments were analyzed at high temporal resolution using low-cost analytical approaches (color tracers, X-ray fluorescence, and magnetic susceptibility). As the measurements of magnetic susceptibility provide only one variable, they were used for cross-validation of the results obtained with the two alternative tracing methods. The comparison of the tracer sets and three mixing models (non-negative least squares, Bayesian mixing model SIMMR, and partial least squares regression) allowed us to estimate different sources of errors inherent in sediment fingerprinting studies and to assess the challenges and opportunities of using these fingerprinting methods.

Results and discussion

All tracer sets and mixing models could identify marly badlands as the main source of suspended sediments. However, the percentage of source contributions varied between the 11 flood events in the catchment. The mean contribution of the badlands varied between 74 and 84%; the topsoils on sedimentary geology ranged from 12 to 29% and the basaltic topsoils from 1 to 8%. While for some events the contribution remained constant, others showed a high within-event variability of the sediment provenance. Considerable differences in the predicted contributions were observed when different tracer sets (mean RMSE 19.9%) or mixing models (mean RMSE 10.1%) were used. Our result shows that the choice of the tracer set was more important than the choice of the mixing model.

Conclusions

These results highlighted the importance of using multi-tracer multi-model approaches for sediment fingerprinting in order to obtain reliable estimates of source contributions. As a given fingerprinting approach might be more sensitive to one type of error, i.e., source variability, particle size selectivity, multi-tracer ensemble predictions allow to detect and quantify these potential biases. High sampling resolution realized with low-cost methods is important to reveal within- and between-event dynamics of sediment fluxes and to obtain reliable information of main contributing sources.

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Design and fabrication of novel thiourea coordination compounds as potent inhibitors of bacterial growth

Design and fabrication of novel thiourea coordination compounds as potent inhibitors of bacterial growth

Design and fabrication of novel thiourea coordination compounds as potent inhibitors of bacterial growth, Published online: 12 February 2019; doi:10.1038/s41429-019-0147-2

Design and fabrication of novel thiourea coordination compounds as potent inhibitors of bacterial growth

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In vitro activities of antimicrobial peptides and ceragenins against Legionella pneumophila

In vitro activities of antimicrobial peptides and ceragenins against Legionella pneumophila

In vitro activities of antimicrobial peptides and ceragenins against <i>Legionella pneumophila</i>, Published online: 12 February 2019; doi:10.1038/s41429-019-0148-1

In vitro activities of antimicrobial peptides and ceragenins against Legionella pneumophila

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Lactacystin: first-in-class proteasome inhibitor still excelling and an exemplar for future antibiotic research

Lactacystin: first-in-class proteasome inhibitor still excelling and an exemplar for future antibiotic research

Lactacystin: first-in-class proteasome inhibitor still excelling and an exemplar for future antibiotic research, Published online: 12 February 2019; doi:10.1038/s41429-019-0141-8

Lactacystin: first-in-class proteasome inhibitor still excelling and an exemplar for future antibiotic research

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Propofol and isoflurane on intraoperative motor evoked potentials

The effects of propofol and isoflurane on intraoperative motor evoked potentials during spinal cord tumour removal surgery - A prospective randomised trial p. 92

Parthiban Velayutham, Verghese T Cherian, Vedantam Rajshekhar, Krothapalli S Babu

DOI:10.4103/ija.IJA_421_18  

Background and Aims: Transcranial electrical stimulation (TES) elicited intraoperative motor evoked potentials (iMEPs), are suppressed by most anaesthetic agents. This prospective randomised study was carried out to compare the effects of Isoflurane and Propofol on iMEPs during surgery for spinal cord tumours. Methods: A total of 110 patients were randomly divided into two groups. In group P, anaesthesia was maintained with intravenous propofol (6.6 ± 1.5 mg/kg/hr) and in group I anaesthesia was maintained with isoflurane (0.8 ± 0.1% minimal alveolar concentration (MAC). An Oxygen- air mixture (FiO2-0.3) was used in both groups. TES-iMEPs were recorded from tibialis anterior, quadriceps, soleus and external anal sphincter muscles in 60 of 90 patients. Statistical analysis was performed with Pearson correlation and Paired 't' tests. Results: Successful baseline iMEPs were recorded in 74% of patients in Group P and in 50% of patients in Group I. Age and duration of symptoms influenced the elicitation of baseline iMEPs under isoflurane (r = −0.71, −0.66 respectively, P < 0.01) as compared to propofol (r = −0.60, −0.50 respectively, P < 0.01). The mean stimulus strength required to elicit the baseline iMEPs were lesser in propofol (205 ± 55Volts) as compared to isoflurane (274 ± 60 Volts). Suppression of the iMEP responses was less under propofol (7.3%) as compared to isoflurane anaesthesia (11.3%) in patients with no preoperative neurological deficits. Conclusion: iMEPs are better maintained under propofol anaesthesia (6-8 mg/kg/hr) when compared with isoflurane (0.7-0.9 MAC). in patients undergoing surgery for excision of spinal cord tumours.

Analgesia nociception index and systemic haemodynamics during anaesthetic induction and tracheal intubation

: A secondary analysis of a randomised controlled trial p. 100

Kamath Sriganesh, Kaushic A Theerth, Madhusudan Reddy, Dhritiman Chakrabarti, Ganne Sesha Umamaheswara Rao

DOI:10.4103/ija.IJA_656_18  

Background and Aims: Direct laryngoscopy and tracheal intubation is a noxious stimulation that induces significant stress response. Currently, this nociceptive response is assessed mainly by haemodynamic changes. Recently, analgesia nociception index (ANI) is introduced into anaesthesia practice and provides objective information about parasympathetic (low nociceptive stress) and sympathetic (high nociceptive stress) balance, which reflects the degree of intraoperative nociception/analgesia. This study evaluated the changes in ANI and haemodynamics during anaesthetic induction and intubation, and their correlation during tracheal intubation. Methods: Sixty adult patients scheduled for elective brain tumour surgery under general anaesthesia were studied for changes in ANI, heart rate (HR) and mean blood pressure (MBP) during anaesthetic induction and intubation. This was a secondary analysis of a previously published trial. Linear mixed effects model was used to evaluate changes in ANI, HR and MBP and to test correlation between ANI and haemodynamics. Results: Anaesthetic induction reduced ANI (but not below the critical threshold of nociception of 50) and MBP, and increased the HR (P < 0.001). Direct laryngoscopy and tracheal intubation resulted in increase in HR and MBP with decrease in ANI below the threshold of 50 (P < 0.001). A linear negative correlation was observed between ANI and HR; r = −0.405, P < 0.001, and ANI and MBP; r = −0.415, P= 0.001. Conclusion: Significant changes are observed in ANI during anaesthetic induction and intubation. There is a negative linear correlation between ANI and systemic haemodynamics during intubation.

Altered anatomical relationship between internal jugular vein and common carotid artery with supraglottic airway in children

Ultrasonographic assessment of altered anatomical relationship between internal jugular vein and common carotid artery with supraglottic airway in children: LMA vs i-gel™ p. 114

Rakhi Khemka, Sonal Rastogi, Arunangshu Chakraborty, Subir Sinha

DOI:10.4103/ija.IJA_747_18  

Background and Aims: Use of ultrasound (US) during internal jugular vein (IJV) cannulation reduces the risk of associated complications in children under general anaesthesia. We studied the effect of two varieties of supraglottic airway device (SGAD), the Ambu AuraOnce™ LMA (Ambu LMA), and i-gel™ on the anatomical relationship between IJV and common carotid artery (CCA). Both these SGAD are known to have similar safety profile in paediatric age group. Methods: A total of 62 children were randomly allocated into 2 groups. In group L: Ambu AuraOnce™ LMA (Ambu LMA) and in group I: i-gel™ was inserted. After induction of GA, US images were taken with head in neutral and 30 degrees rotated to the opposite side both before and after insertion of SGAD. The relationship between IJV and CCA was noted as lateral, anterolateral, and anterior. Degree of overlap between the two vessels was also noted. Results: Lateral rotation of the head significantly alters the relationship between the IJV and CCA and also increases the degree of overlap between them. Though these changes were noted to be similar with both varieties of SGAD, but between the two varieties of SGAD, these changes were significantly higher in group I. Conclusion: Higher oesophageal sealing pressure exerted by i-gel™ as compared to other SGAD might cause increased distortion of the surrounding soft tissue leading to altered anatomical relationship between IJV and CCA, which makes the CCA vulnerable to puncture during IJV cannulation using landmark technique.

Anaesthetic management of bilateral temporomandibular joint ankylosis with cervical spine fusion for total alloplastic joint replacement in a patient with ankylosing spondylitis

LETTER TO EDITOR

Year : 2019  |  Volume : 63  |  Issue : 2  |  Page : 148-150

Saurav, Shalendra Singh, S Kiran, Alok Jaiswal
Department of Anaesthesiologist and Critical Care, Armed Forces Medical College, Pune, Maharashtra, India

Date of Web Publication

11-Feb-2019

Correspondence Address:
Dr. Shalendra Singh
Department of Anaesthesiologist and Critical Care, Armed Forces Medical College, Pune - 411 040, Maharashtra 
India

Source of Support: None, Conflict of Interest: None

Check

DOI: 10.4103/ija.IJA_573_18

 

How to cite this article: Saurav, Singh S, Kiran S, Jaiswal A. Anaesthetic management of bilateral temporomandibular joint ankylosis with cervical spine fusion for total alloplastic joint replacement in a patient with ankylosing spondylitis. Indian J Anaesth 2019;63:148-50

How to cite this URL: Saurav, Singh S, Kiran S, Jaiswal A. Anaesthetic management of bilateral temporomandibular joint ankylosis with cervical spine fusion for total alloplastic joint replacement in a patient with ankylosing spondylitis. Indian J Anaesth [serial online] 2019 [cited 2019 Feb 12];63:148-50. Available from: http://www.ijaweb.org/text.asp?2019/63/2/148/251972

Sir,

It is not very common to manage a patient with ankylosing spondylitis (AS) and bilateral 'temporomandibular joint' (TMJ) ankylosis with cervical spine fusion to undergo alloplastic joint replacement. However, anaesthetic management of such patients in the context of difficult airway has been described.^[1] AS presents challenges to the anaesthesiologist as a consequence of potential difficult airway, cardiovascular, respiratory complications and increased risk of neurological complications. Incidence of TMJ involvement is 4–24% in AS; however, a case where bilateral TMJ ankylosis associated with cervical spine fusion and AS having undergone total alloplastic joint replacement is rare.

A 39-year-old male patient with complaint of difficulty in mouth opening for the past 18 years presented for bilateral alloplastic TMJ replacement. Airway examination revealed 6 mm of interincisor distance, grade IV Mallampati score with no lateral movement of the mandible, along with rigidity of cervical spine. Computerised tomography scan of both TMJs confirmed severe ankylosis [Figure 1]. X-ray of the cervical spine revealed fusion of the cervical spine [Figure 2]. All routine investigations including haemogram, biochemistry, chest X-ray and ECG were within normal limits. No abnormality was detected in lung function tests and arterial blood gas analysis.

Figure 1: Three-dimensional CT scan of patient showing bilateral TMJ ankylosis Click here to view

Figure 2: Lateral view X-ray of neck showing cervical spine fusion Click here to view

He was planned for general anaesthesia with awake fibreoptic nasal intubation which is the gold standard^[2] in view of restricted mouth opening and potential loss of airway under muscle relaxant. In the operation theatre, trolley for emergency surgical tracheostomy was kept ready. All standard monitoring devices were attached and the patient was pre-medicated with inj. glycopyrrolate 0.2 mg intravenous (IV) and inj. midazolam 1 mg IV. For nasal decongestion and topical anaesthesia, xylometazoline 0.05% nasal drops (3–5 drops) were instilled and nasal packing by gauze soaked in 2% lignocaine was done. Recurrent laryngeal nerve block was performed by injecting 2 ml of 4% lignocaine after piercing the cricothyroid membrane. Mild sedation for the awake fibreoptic intubation was achieved with inj. dexmedetomidine 20 μg IV and inj. ketamine 20 mg IV. After pre-oxygenation, both nasal passages were lubricated with lubricant jelly and fibreoptic bronchoscope was passed through the left nasal passage. After manipulation, epiglottis was visualised, and with spray-as-you-go technique using 4% topical lignocaine glottis was visualised. The pre-loaded flexo-metallic cuffed endotracheal tube size 7.0 mm was gently advanced over the bronchoscope. The position of the tube was confirmed by ETCO₂ and the anaesthesia was induced with inj. propofol 120 mg IV and maintained on O₂, N₂O, isoflurane and vecuronium. Intraoperative period was uneventful. Operating on each side of his face posed a practical problem because of the rigidity of his cervical spine, which required a bodily tilt of the operating table by 15–25° on each side. Neck support was used during anaesthesia and movements of the neck in the presence of neuromuscular blockade were restricted to avoid neurological injury. Three litres of crystalloid were infused intraoperatively with a total blood loss of 350 ml. The patient was shifted to surgical intensive care unit (SICU) with endotracheal tube in situ and maintained on assisted ventilation support in view of difficult airway and risk of airway oedema. After 12 h, the trachea was extubated uneventfully in SICU over an airway exchange catheter in view of potential difficult extubation. The same precautions regarding patient positioning and neck movement were applied at emergence, as with intubation. The patient was discharged on the seventh postoperative day.

To conclude, we successfully managed a case of AS with bilateral TMJ ankylosis having cervical spine fusion undergoing alloplastic joint replacement. It is emphasised that the prime concerns of the anaesthesiologists are to maintain a patent airway and maintain immobility of cervical spine, apart from the other anaesthetic concerns during perioperative management of such patients.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 

References

1.	Dave N, Sharma RK. Temporomandibular joint ankylosis in a case of ankylosing spondylitis – Anaesthetic management. Indian J Anaesth 2004;48:54-6.     [Full text]
2.	Vas L, Sawant P. A review of anaesthetic technique in 15 paediatric patients with temporomandibular joint ankylosis. Paediatr Anaesth 2001;11:237-44.

Figures

  [Figure 1], [Figure 2]

Anaesthesia for tracheal reconstruction

LETTER TO EDITOR

Year : 2019  |  Volume : 63  |  Issue : 2  |  Page : 152-153

Anaesthesia for tracheal reconstruction – Neither a dilemma nor a catastrophe

Vaijayanti Nitin Gadre, Deoshree Bal Ramteke, Sushila Ramkishan Yadav, Esmat Gulamraza Mundrawala
Department of Anesthesiology, Grant Government Medical College, Mumbai, Maharashtra, India

Date of Web Publication

11-Feb-2019

Correspondence Address:
Dr. Vaijayanti Nitin Gadre
'Sniti-11', General Jagannath Bhosale Marg, Oppo. Mantralaya, Near Sachivalaya Gymkhana, Mumbai - 400 021, Maharashtra 
India

Source of Support: None, Conflict of Interest: None

Check

DOI: 10.4103/ija.IJA_629_18

 

How to cite this article: Gadre VN, Ramteke DB, Yadav SR, Mundrawala EG. Anaesthesia for tracheal reconstruction – Neither a dilemma nor a catastrophe. Indian J Anaesth 2019;63:152-3

How to cite this URL: Gadre VN, Ramteke DB, Yadav SR, Mundrawala EG. Anaesthesia for tracheal reconstruction – Neither a dilemma nor a catastrophe. Indian J Anaesth [serial online] 2019 [cited 2019 Feb 12];63:152-3. Available from: http://www.ijaweb.org/text.asp?2019/63/2/152/251975

Sir,

Narrowing of trachea due to prolonged intubation, thyroid mass or cervical malignancies is known. We report a case of tracheal stenosis for proposed tracheal reconstruction.

A 21-year-old 70-kg tracheostomised male had difficulty in breathing through his 4.5-mm tracheostomy tube. He had undergone craniotomy 4 years back, had received mechanical ventilation for 15 days and was discharged after a month with a 7.5 mm tracheostomy tube. Over a period of 4 years, the trachea could not be decannulated even after repeated laser dilatation. Computerised tomography of neck showed 1.4-cm long near-complete (7 mm diameter) obliteration of trachea at C7 to T1 level. The patient was posted for anterior tracheoplasty with tibial periosteal grafting. In the operating room, difficult airway cart including additional small-sized endotracheal tubes was kept ready. The patient was positioned supine, monitors were attached and intravenous access was secured. Nebulisation was done with 2% lignocaine 1 ml for 15 min and for premedication, intravenous ondansetron 4 mg, glycopyrrolate 0.2 mg, midazolam 1 mg, hydrocortisone 100 mg and fentanyl 60 μg were given slowly. Pre-oxygenation was done with closed circuit attached to the tracheostomy tube; anaesthesia was induced with propofol 2 mg/kg and a ratio of O₂:N₂O was maintained at 50:50 and 2% sevoflurane was given on spontaneous-assisted ventilation. Flexible fibre-optic nasopharyngolaryngoscope was introduced through left nostril by the surgeon to study the vocal cord dynamics and rule out inter-arytenoid and subglottic fibrosis. Overhanging epiglottis was also ruled out before deciding definitive tracheal correction. For examining the sub-glottis up to carina, vecuronium 3 mg IV was given. This step helped surgeons to count total intact tracheal rings above the stoma to plan the extent of tracheal resection or trachaeoplasty with stenting. Only 10 rings were present (normal 16–18); hence, 6-cm long and 1.8-mm internal diameter stent (Montgomery T tube) was inserted to ensure optimal tracheal length. To allow surgery as well as uninterrupted ventilation at this step, laryngeal mask airway (LMA classic size 4) was inserted, cuff was inflated, ventilation was confirmed and continued via the first anaesthesia workstation. The tracheostomy tube was removed [Figure 1] and the open stoma was secured with a sterile cuffed flexo-metallic endotracheal tube (size 5). The machine end of this tube was blocked by anaesthesiologist's gloved finger to prevent leakage of ventilated gases. As and when required, this endotracheal tube was connected to a second anaesthesia workstation. Ventilation continued alternatively through distal endotracheal tube or LMA, in coordination with proximal and distal end suturing, respectively, of the stent inside the trachea.

Figure 1: Figure showing open stoma and LMA inserted Click here to view

A horizontal incision was taken below the level of stoma, a subplatysmal flap was elevated, the strap muscles were separated and the trachea with stoma was exposed. The perpendicular end of the T-tube was cut and the longitudinal portion inserted from the lower end of the cricoid cartilage superiorly up to the first tracheal ring inferiorly. The anterior wall of the resected trachea was reconstructed with a 5-cm × 2-cm tibial periosteum graft, haemostasis was achieved and wound was closed in layers after confirming no air leak. Ventilation was controlled through the LMA throughout until closure. After return of spontaneous ventilation, reversal was done with neostigmine 0.05 mg/kg and glycopyrrolate 0.008 mg/kg. Patient was extubated and shifted to critical care for monitoring.

Anaesthesia for surgical procedures on the trachea and major airways is essentially perilous because an already compromised airway needs to be shared with the surgeon. The unique challenge is the ability to maintain adequate oxygenation and uninterrupted ventilation. A discrete plan for ventilation at each surgical step is needed. Considering the extent of tracheal pathology, preparations for alternative modes of ventilation are employed in coordination with the surgeon. In the face of an open airway, ventilation can be managed by manual oxygen through a small bore anode tube placed through the upper tracheal lesion combined with a distal endotracheal or bronchial tube inserted distal to the stenosis.^[1] Earlier belief was that maximum length of the trachea that can be resected is 2 cm.^[2] Lesions requiring resection of more than 6 cm or more than 50% of total length of trachea in adults or more than 30% trachea in children are considered inoperable. Longer segment involvement after previous surgery needs patch augmentation or slide trachaeoplasty.^[3] Tissue engineering advances have successfully used cadaveric allografts and autologous tissue.^[4]

In the present case, T-tube was appropriate to palliate the obstruction. It allowed respiration through nasopharynx, preserved humidification and speech. It has no tissue irritation and hence proved useful.

Patient was advised postoperatively to retain follow-up until complete reepithelialisation and undergo stent removal.

Meticulous preoperative planning, precise airway control and perfect coordination to oxygenate the patient with each distinct surgical step were the essence of our successful management of anaesthesia during transected airway surgery.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 

References

1.	Barash PG, Cullen BF, Stoelting RK. Anaesthesia for thoracic surgery. In: Clinical Anaesthesia 5th ed, ch. 29. Philadelphia: Lippincott Williams and Wilkins. A Walter Kluwer company; 2006. p. 813-55.
2.	Heitmiller RF. Tracheal release maneuvers. Chest Surg Clin N Am 1996;6:675-83.
3.	Grillo HC. Primary tracheal tumours. In: HC Grillo, editor. Surgery of Trachea and Bronchi. Hamilton: BC Decker; 2004, p. 791-802.
4.	Jungebluth P, Moll G, Baiguera S, Macchiarini P. Tissue engineered airway: A regenerative solution. Clinical Pharmacol Therap 2012;91:81-93.

Figures

  [Figure 1]

Displaced paediatric central venous catheter causing extravasation of intravenous fluid

LETTER TO EDITOR

Year : 2019  |  Volume : 63  |  Issue : 2  |  Page : 157-159

Displaced paediatric central venous catheter causing extravasation of intravenous fluid due to relatively longer gap between the distal and proximal lumens

Nishith Govil¹, Mridul Dhar¹, Kesari Masaipeta¹, Intezar Ahmed^2
1 Department of Anaesthesiology and Critical Care, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India
² Department of Paediatric Surgery, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India

Date of Web Publication

11-Feb-2019

Correspondence Address:
Dr. Mridul Dhar
Department of Anaesthesiology and Critical Care, All India Institute of Medical Sciences, Rishikesh, Uttarakhand 
India

Source of Support: None, Conflict of Interest: None

Check

DOI: 10.4103/ija.IJA_674_18

 

How to cite this article: Govil N, Dhar M, Masaipeta K, Ahmed I. Displaced paediatric central venous catheter causing extravasation of intravenous fluid due to relatively longer gap between the distal and proximal lumens. Indian J Anaesth 2019;63:157-9

How to cite this URL: Govil N, Dhar M, Masaipeta K, Ahmed I. Displaced paediatric central venous catheter causing extravasation of intravenous fluid due to relatively longer gap between the distal and proximal lumens. Indian J Anaesth [serial online] 2019 [cited 2019 Feb 12];63:157-9. Available from: http://www.ijaweb.org/text.asp?2019/63/2/157/251981

Sir,

A 4-month-old female child weighing 6 kg was posted for surgical excision of a sacrococcygeal teratoma. Pre-anaesthetic evaluation revealed no other significant history or findings on examination. On the day of surgery, the child was taken into the operation theatre and general anaesthesia was induced uneventfully. After discussion with surgical team, decision was taken to place a central venous catheter (CVC) as the patient had difficult peripheral venous access and was also going to require a relatively longer duration of IV antibiotics.

A 4.5-French, 6-cm double-lumen CVC (Vygon®) was inserted into the right internal jugular vein (IJV) under ultrasound guidance (USG). The catheter was introduced using over the wire Seldinger technique and position was confirmed by smooth aspiration of blood from both ports and visualization of catheter tip in the IJV lumen on USG. The catheter was fixed at 5 cm at the skin using the secondary fixation wing, as the blood flow was achieved at ~ 1.5 cm during initial puncture with the introducer needle. After securing the catheter with sutures and flushing the catheter with heparinised saline, the patient was turned prone for the surgery with the head turned sideways. IV fluid was not given through the central line intraoperatively. The surgery and eventual recovery were uneventful. Backflow of blood from the catheter during aspiration was confirmed once more at the end of the surgery.

Two hours post-operatively, IV fluids were initiated via the central line (proximal port). Soon after starting the fluid, the child developed a swelling in the submandibular region, which was soft, gradually increasing in size and tender to touch [Figure 1]. The IV fluid was stopped immediately, and a chest X-ray and USG examination of the swelling was ordered. The chest X-ray revealed a neck swelling which was more on the right side. The CVC appeared to be in place but seemed to have curved slightly in the subcutaneous tissue [Figure 2]. USG of the neck was suggestive of fluid collection in the subcutaneous plane and the catheter tip was still visible in the IJV lumen. The catheter was removed and a gentle compression was given on the swelling. The swelling subsided to near normal after 7–8 h. On examination of the catheter, it was observed that the proximal lumen was almost 2 cm from the tip of the catheter [Figure 3].

Figure 1: Submandibular swelling following fluid infusion Click here to view

Figure 2: Curving of catheter in the subcutaneous tissue Click here to view

Figure 3: Relatively longer distance of proximal lumen from distal tip Click here to view

Central venous access is often required in younger paediatric patients during elective surgeries.^[1] Although technically challenging, it offers a smooth intra- and post-operative course and avoidance of multiple pricks. Sizes of CVCs ranging from 3 to 5.5 french are available commercially. Cases of displaced and migrated CVC's have been reported and are quite common especially in the paediatric population.^[2]

In the current case, it was hypothesised that the even though the initial placement of the CVC was correct, it could have migrated and curved during prone positioning due to sideways turning of the head; or subsequently during the post-operative period when the child was actively moving her neck. As the distance of the proximal lumen was nearly 2 cm from the tip, it could have led to slipping of the proximal lumen in and out of the IJV into the subcutaneous tissue; even though the rest of the catheter was still inside the vein.

Paediatric CVC's of different makers have varied specifications and different arrangement of lumens. In the present case, the CVC had a relatively longer gap between the proximal lumen and the distal tip, which increased the chances of the proximal lumen slipping out of the vein. When deciding the depth of insertion of CVC's in paediatric patients, in addition to the age- and height-based formulas,^[3] one should also consider the arrangement and distance of the various lumens from the tip to minimise chances of CVC mal-positioning and prevent inadvertent extravasation of IV fluid or drugs into subcutaneous tissue.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 

References

1.	Scott-Warren VL, Morley RB. Paediatric vascular access. BJA Educ 2015;15:199-206.
2.	Roldan CJ, Paniagua L. Central venous catheter intravascular malpositioning: Causes, prevention, diagnosis, and correction. West J Emerg Med 2015;16:658-64.
3.	Andropoulos DB, Bent ST, Skjonsby B, Stayer SA. The optimal length of insertion of central venous catheters for pediatric patients. Anesth Analg 2001;93:883-6.

Figures

  [Figure 1], [Figure 2], [Figure 3]