An ncRNA transcriptomics-based approach to design siRNA molecules against SARS-CoV-2 double membrane vesicle formation and accessory genes

BACKGROUND

The corona virus SARS-CoV-2 is the causative agent of recent most global pandemic. Its genome encodes various proteins categorized as non-structural, accessory, and structural proteins. The non-structural proteins, NSP1-16, are located within the ORF1ab. The NSP3, 4, and 6 together are involved in formation of double membrane vesicle (DMV) in host Golgi apparatus. These vesicles provide anchorage to viral replicative complexes, thus assist replication inside the host cell. While the accessory genes coded by ORFs 3a, 3b, 6, 7a, 7b, 8a, 8b, 9b, 9c, and 10 contribute in cell entry, immunoevasion, and pathological progression.

METHODS

This in silico study is focused on designing sequence specific siRNA molecules as a tool for silencing the non-structural and accessory genes of the virus. The gene sequences of NSP3, 4, and 6 along with ORF3a, 6, 7a, 8, and 10 were retrieved for conservation, phylogenetic, and sequence logo analyses. siRNA candidates were predicted using siDirect 2.0 targeting these genes. The GC content, melting temperatures, and various validation scores were calculated. Secondary structures of the guide strands and siRNA-target duplexes were predicted. Finally, tertiary structures were predicted and subjected to structural validations.

RESULTS

This study revealed that NSP3, 4, and 6 and accessory genes ORF3a, 6, 7a, 8, and 10 have high levels of conservation across globally circulating SARS-CoV-2 strains. A total of 71 siRNA molecules were predicted against the selected genes. Following rigorous screening including binary validations and minimum free energies, final siRNAs with high therapeutic potential were identified, including 7, 2, and 1 against NSP3, NSP4, and NSP6, as well as 3, 1, 2, and 1 targeting ORF3a, ORF7a, ORF8, and ORF10, respectively.

CONCLUSION

Our novel in silico pipeline integrates effective methods from previous studies to predict and validate siRNA molecules, having the potential to inhibit viral replication pathway in vitro. In total, this study identified 17 highly specific siRNA molecules targeting NSP3, 4, and 6 and accessory genes ORF3a, 7a, 8, and 10 of SARS-CoV-2, which might be used as an additional antiviral treatment option especially in the cases of life-threatening urgencies.

Enhanced Goat Milk MUFA Quality via Date Pit Supplementation: A Time-Based Pattern Recognition Analysis Utilizing Agricultural Waste Byproduct

Date pits are agricultural waste byproducts and are available in tons yearly. Milk MUFAs are lipids beneficial for health and sorted out for food product development. This work is aimed at researching the effect of supplementing dairy goats with date pit powder (DPP) as a source of fatty acids (FA), an alternative to enhancing the unsaturated FA in milk and analysed via chemometrics in a 3-month supplementation-based study. Saanen-Boer crossed dairy goats were divided into six groups comprising of control, 10 g and 20 g both for Ajwa DPP (high-quality dates) and Mariami DPP (agricultural waste byproduct), and another 30 g for Mariami DPP only. The supplementation exercise was done daily on each dairy goat. The DPP and milk samples were analysed for its FA profile applying GC-FID and followed by chemometric techniques, namely, PCA and PLS. Results indicated that the n-6/n-3 ratio was the highest for the unsupplemented group compared to the DPP-treated goats with lower n-6/n-3 ratios. The M30 group showcased the most promising health-related class of FAs viewed by 3D PCA and PLS model clustering patterns, in particular monounsaturated FA (MUFA) (C18:1n9c or oleic acid). These results suggest that Mariami DPP supplementation at higher doses and time to lactating Saanen-Boer cross goats can be a means to milk FA quantity and quality enhancement and that chemometrics via pattern recognition can be useful statistical tools when dealing with overwhelming data.

Study of resveratrol against bone loss by using in-silico and in-vitro methods

By applying the in-silico method, resveratrol was docked on those proteins which are responsible for bone loss. The Molecular docking data between the resveratrol and Receptor activator of nuclear factor-kappa-Β ligand [RANKL] receptors proved that resveratrol binds tightly to the receptors, showed the highest binding affinities of -6.9, -7.6, -7.1, -6.9, -6.7, and -7.1 kcal/mol. According to in-vitro data, Resveratrol reduced the osteoclasts after treating Marrow-Derived Macrophages [BMM] with Macrophage colony-stimulating factor [MCSF] 20ng / ml and RANKL 50ng / ml, with different concentrations of resveratrol (2.5, 10 μg / ml) For 7 days, the cells were treated with MCSF (20 ng / ml) and RANKL (40 ng / ml) together with concentrated trimethyl ether and resveratrol (2.5, 10 μg / ml) within 12 hours. Which, not affect cell survival. After fixing osteoclast cells with formaldehyde fixative on glass coverslip followed by incubation with 0.1% Triton X-100 in PBS for 5 min and after that stain with rhodamine phalloidin staining for actin and Hoechst for nuclei. Fluorescence microscopy was performed to see the distribution of filaments actin [F.actin]. Finally, resveratrol reduced the actin ring formation. Resveratrol is the best bioactive compound for drug preparation against bone loss.

Induction of secondary metabolites on nanoparticles stress in callus culture of Artemisia annua L

Nanoparticles are known bio elicitors in plant biotechnology. Different concentrations of ZnO, CuO and CoO nanoparticles were used for the enhanced accumulation of secondary metabolites and antioxidant activities in the callus derived from root, shoot and leaf of Artemisia annua L. Biomass of callus was somehow affected on high concentrations of Nps. Phenolic content was observed maximum (60µg) in shoot callus at 0.1mg/l of CuONps. Total antioxidant activity was observed maximum (33µg) in root callus at 0.1mg/l of ZnOnps. Total reducing power maximum (33µg) was observed in root callus at concentration of 0.05 mg/l of CoONps. Maximum radical scavenging activity was observed in shoot callus at 0.05mg/l of ZnONps. Rutin gallic acid and caffic acid were also determined in most of the samples by HPLC. The study concludes that different Nps have positive effect on the induction of secondary metabolites in A.annua plant.

FAVIPIRAVIR AND DEXAMETHASONE IN MANAGEMENT OF SARS-COV2 INFECTION

Background. The clinical presentation of Coronavirus disease 19 (COVID-19) varies from mild symptoms to severe illness including multiorgan dysfunction. Favipiravir is an antiviral agent which has been previously used for treatment of influenza and was recently approved for treatment of mild to moderate COVID-19 in India. Objective. The Objective of this study was to assess the role of Favipiravir and Dexamethasone in patients with COVID-19. Methods. A total of 17 patients were included in this observational study. The included patients were RT-PCR for SARS-Cov-2 positive with increased inflammatory markers. All patients received Antiviral therapy, Anticoagulation (Enoxaparin 0.4mg subcutaneous twice daily), Steroids (Dexamethasone 8mg daily for 5days and 4mg daily for 5 days). Viral clearance (time to RT-PCR negative), time to defervescence after antiviral therapy, time to become independent of Oxygen support was studied. Results. Fever, myalgias, dry cough and dyspnea were the commonest presentation of COVID-19. All of our patients had lymphopenia. In our study 11 (64.7%) patients had bilateral ground glass opacities on CT chest while 6 had consolidation in addition to ground glass opacities. In two patients, who required non-invasive ventilation, Favipiravir was stopped and these patients received Remdesivir for a total of 5 days. In patients who received Favipiravir only, the Median time to RT-PCR negative, defervescence and oxygen independence was 8,3 and 6 days respectively. Conclusion. Our observational study demonstrated improvement in the majority of patients with COVID-19 with use of Favipiravir. Additional studies are needed to compare the efficiency of Favipiravir with Remdesivir.

Antioxidant and antimicrobial properties of Indo-Malayan stingless bee (Heterotrigona itama) honey from different seasons and distribution of flowers

The quality of honey produced by stingless bees can be affected by a variety of factors. Different seasons may have an influence on stingless bee behaviour while different flower sources may affect the properties of stingless bee honey. Thus, this study aimed to determine the antioxidant and antimicrobial properties of stingless bee honey from different multifloral sources collected during dry and rainy seasons. Honey was collected from hives placed in two different areas with multifloral (area A and B). The difference between these areas was area A only planted with two types of flowers (with stevia) and area B with more than two flowers. Pollen in the honey samples was identified to confirm the seasonal variations. The antioxidative potential of the honey samples was determined using total phenolic content (TPC), DPPH and FRAP assays and total carotenoid content (TCC). Antimicrobial properties were analysed using well diffusion method (mm) against the foodborne pathogens Escherichia coli, Staphylococcus aureus, Listeria monocytogenes and Salmonella enterica serovar Typhimurium. The results revealed that honey harvested during the dry season showed higher antioxidant properties compared to those harvested in the rainy season. The highest antioxidant activities were measured in honey samples taken from area B. Nevertheless, honey harvested in both seasons showed antimicrobial properties against all tested food pathogens, with the dry season samples showing the highest inhibition. Surprisingly, only honey from area A present showed no antimicrobial effect against E. coli. This study showed that the antioxidant and antimicrobial properties of multifloral stingless bee honey are strongly affected by seasonal differences and the distribution of the flowering plant

Inhibition of L-NAME-induced hypertension by combined treatment with apocynin and catalase: the role of Nox 4 expression

Reactive oxygen species (ROS) such as superoxide (O2-) generated by NAD(P)H oxidases have emerged as important molecules in blood pressure regulation. This study investigated the effect of apocynin and catalase on blood pressure and renal haemodynamic and excretory function in an L-NAME induced hypertension model. Forty Male Wistar-Kyoto (WKY) rats (n=8 per group) were treated with either: vehicle (WKY-C); L-NAME (WKY-L, 15 mg/kg/day in drinking fluid); WKY-L given apocynin to block NAD(P)H oxidase (WKY-LApo, 73 mg/kg/day in drinking water.); WKY-L given catalase to enhance ROS scavenging (WKY-LCat, 10000 U/kg/day i.p.); and WKY-L receiving apocynin plus catalase (WKY-LApoCat) daily for 14 days. L-NAME elevated systolic blood pressure (SBP), 116+/-1 to 181±4 mmHg, reduced creatinine clearance, 1.69+/-0.26 to 0.97+/-0.05 ml/min/kg and fractional sodium excretion, 0.84+/-0.09 to 0.55+/-0.09 % at day 14. Concomitantly, plasma malondialdehyde (MDA) increased six fold, while plasma total superoxide dismutase (T-SOD), plasma nitric oxide (NO) and plasma total antioxidant capacity (T-AOC) were decreased by 60-70 % and Nox 4 mRNA expression was increased 2-fold. Treatment with apocynin and catalase attenuated the increase in SBP and improved renal function, enhanced antioxidative stress capacity and reduced the magnitude of Nox4 mRNAs expression in the L-NAME treated rats. This study demonstrated that apocynin and catalase offset the development of L-NAME induced hypertension, renal dysfunction and reduced oxidative stress status, possibly contributed by a reduction in Nox4 expression during NOS inhibition. These findings would suggest that antioxidant compounds such as apocynin and catalase have potential in treating cardiovascular diseases.

Palmar psoriasis or missed BCC?-A case report

Case report

A 76-year-old Caucasian woman with a history of previous BCCs excised from the head and legs was referred from the dermatology team with a biopsy proven superficial BCC to the left palm. The patient had presented to the dermatology team with the same lesion 7 years prior to the definitive diagnosis. The lesion was described as 27 × 15 mm scaly, poorly-defined, plaque-like lesion to the central palm. There was no ulceration or visible telangiectasia. At the time, an initial diagnosis of psoriasis was given and she received several courses of topical treatments to no avail. Eventually, a biopsy was taken which revealed a multifocal superficial BCC. After unsuccessful attempts at treating with topical Imiquimod, the lesion was surgically excised and resurfaced with a full thickness skin graft.

Discussion

The current understanding that BCCs derive from cells of the hair follicle cannot explain their appearance on the palm. Alternative hypotheses have been proposed as to their actual origin which would account for this rare occurrence. Ultimately, histology can determine the nature of the lesion. We urge clinicians encountering atypical, non-healing lesions to glabrous skin to keep in mind a diagnosis of skin cancer as a delayed diagnosis can lead to increased morbidity.

Prevalence of hepatitis B virus infection among pregnant women in Jos, Nigeria

Objectives:

The study sought to determine the prevalence and risk factors associated with Hepatitis B surface antigenemia (HBsAg) positivity among pregnant women in Jos, Nigeria.

Methodology:

This was a cross-sectional study carried out among the pregnant population in five healthcare facilities in Jos, between November 1, 2017 and April 30, 2018. Informed consent was obtained, and data on sociodemographic and risk factors for hepatitis B virus (HBV) infection were collected. Hepatitis B viral infection was assessed using the in vitro HBsAg diagnostic rapid kit (Acon Laboratories, USA). Descriptive statistics, Chi-square test, and logistic regression were performed to identify predictors of HBV infection in the study population. All statistical analyses were carried out on STATA version 15.

Results:

Of the 3,238 women enrolled, 7.4% (241/3238) (95% confidence interval [CI] = 6.6% to 8.4%) were HBsAg positive. The absence of HBV vaccination (adjusted odds ratio [AOR] = 2.49; 95% CI = 1.49–4.09; P < 0.001), co-infection with HIV (AOR = 1.90; 95% CI = 1.18–3.08; P = 0.009), and higher parity (AOR = 1.37; 95% CI = 1.04–1.79; P = 0.024) were independently associated with HBV infection in pregnancy.

Conclusions:

The prevalence of HBV infection among pregnant women was high, especially among those without prior vaccination for HBV, those with HIV co-infection and higher parity.

The first two months epidimiological study of COVID-19, related public health preparedness, and response to the ongoing epidemic in Pakistan

As an underdeveloped country, the coronavirus disease 2019 (COVID-19) epidemic has posed a major risk to the health and economy of Pakistan. The SIR (susceptible-infected-recovered) model of epidemiologic analysis predicts that there should have been more cases since late March 2020 in Pakistan. We therefore sought to investigate COVID-19's prevalence and epidemiologic trends in Pakistan. Research for COVID-19 is still in its early stages, so data were collected from official websites and research journals, then analyzed for the disease's prevalence, epidemiology, mortality and recoveries. The results indicated that a rapid increase had indeed occurred in the number of COVID-19 infections in Pakistan, with the first case reported on 25 February, 2020. From 25 February 25 to April, 2020, COVID-19 infected 11,155 people in Pakistan, with 237 deaths (2.12%) and 2527 recoveries (19.96%). We found a statistically significant positive correlation between the prevalence of COVID-19 and the mortality ratio (r = 0.983, r 2 = 0.966; p ≤ 0.05). We concluded that proper management must be undertaken to improve the quarantine system, and the World Health Organization guidelines must be closely followed to cope with COVID-19. There is no vaccine for COVID-19, so antiviral drugs (interferon alfa, ribavirin) may be useful to prevent COVID-19; however, severe control measures implemented in China have significantly mitigated the spread of COVID-19. Suspected and confirmed cases must be treated in separate rooms. Staying home and social distancing are the safe way to proceed.

Fetomaternal Outcome of Pregnancy in Women with Tetralogy of Fallot

This prospective study was done to determine fetomaternal outcomes of pregnancy in women with Tetralogy of Fallot (TOF) and carried out in two centres especially in the care of patients with adult congenital heart disease (CHD) from January 2005 to December 2009. Clinical, haemodynamic and obstetric data were reviewed for pregnant women with TOF. Ten (10) pregnant women were identified in the age range 18 to 47 years. Most of the patients were in the age group of 18 to 27 years, 34 to 36 weeks gestational age (in week) and primi gravida (60%). Right-sided aortic arch (20%) and major anomalies of pulmonary collaterals (30%) were common anomalies anatomical association. Normal vaginal delivery was the mode of delivery (70%) in the majority of the patients. Spontaneous abortions were occurred in 3(30%) patients. Primary maternal cardiac events complicating pregnancies were congestive heart failure (20%), arrhythmias and cardiovascular events (10%). Premature labor (40%) was the most common obstetric complication. Premature birth (40%), fetal demise (20%), neonatal death (10%) and cardiac anomaly at birth (10%) were the offspring complications in the study. Women with TOF can go through pregnancy with a low risk to themselves with frequent treatable complications, but there is a high incidence of miscarriage, premature births and low birth weight. An incidence of congenital anomaly in the fetus is higher than that found in the normal population.

Survival of antibiotic resistant Escherichia coli in vacuumpacked keropok lekor: Food safety alert among SME keropok lekor producers

The microbiological quality of thirty ready-to-eat (RTE) keropok lekor (a sausage shape Malaysian fish product) was evaluated in comparison to microbiological guidelines for ready to eat foods. The two E. coli isolates were subjected to DNA sequencing, identified and tested for their resistance towards fifteen different antibiotics. The survival and growth of the isolated E. coli strains inoculated in keropok lekor at atmospheric air and vacuum packaging were also evaluated. Results revealed that four samples (13.33%) contained Enterobacteriaceae counts that exceeded the recommended allowable counts of 4.0 log₁₀ CFU/g. Unsatisfactory level of coliforms (< 1.7 log₁₀ CFU/g) was also observed in ten of the samples; two of which contained E. coli (2.1 ± 0.17 and 3.7 ± 0.02 log₁₀ CFU/g), suggesting of poor hygiene and sanitation practices. While the 'Possible E10' E. coli strain was observably resistant towards Nalidixic acid (30µg) alone, B10 E. coli isolate was worryingly resistant towards Ampicillin (10µg), Ceftazidime (30µg), Ciprofloxacin (5µg), Ceftriaxone (30µg), Nalidixic acid (30µg) and Tetracycline (30µg). This study also revealed that the growth and survival of the 'Possible E10' and B10 E. coli strains were not significantly affected by vacuum packaging when stored at both 4°C and 28°C. Therefore, intervention programmes to alert and educate smallmedium enterprisers (SMEs) of keropok lekor producers on food safety as well as potential health risks that can be associated due to inappropriate handling procedures of such product, merits consideration.

Esculent coating of spider silk enhanced the preservation and shelf life of apricot

Abstract According to the Food and Agriculture Organization (FAO), roughly one-third of the total food produced is lost globally. The major cause of this wastage is the perishability of fruits and vegetables. Therefore, researchers have endeavored to develop an effective preservation technique. Our study explored the potential application of spider silk as an odourless and edible preservative coating for fruits. The spider silk was collected from spiders reared in the laboratory, following by degumming and dissolution to formulate the silk solution. For this study, apricots were selected as the model fruit. The apricots were dip coated with the formulated silk solution and allowed to dry. In order to enhance the beta sheet content of the silk coating, the fruits were exposed to water annealing for varying intervals of time under vacuum condition. The effect of silk coating and water annealing time period on preservation of fruits was then evaluated morphologically and gravimetrically. The results showed that the fruits, which were used as control, exhibited a greater degree of water loss and suffered from fungal attack. In contrast, the silk coated fruits showed less water loss and were protected from fungal attack. Therefore, the study provides compelling evidence regarding the application of spider silk as a preservative coating.

Thermal studies on Arabic gum - carrageenan polysaccharides film

<p>The main objective of this work is to develop film and study the thermal characteristics of polysaccharides films at various concentration of carrageenan in the mixture by calculating activation energy of polysaccharides films. There were four (4) film samples of two polysaccharides combination; arabic gum (AG) and carrageenan (C) with different formulations; sample A, sample B, sample C and sample D prepared. Sample A film is the control sample that contained only arabic gum and distilled water (DI) with 40% weight arabic gum per volume DI water (w/v%). Meanwhile for sample B and C were prepared with concentration 40 w/v% of Arabic gum and two differents of carrageenan concentrations; 1 w/v% and 10 w/v% respectively. Polyethylene glycol 400 (PEG 400) as a plasticiser was added into sample D film. The sample films were thermally characterized using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) under nitrogen atmosphere. The major thermal transitions as well as, activation energies of the major decomposition stages were determined. Sample A and B films exhibited the highest (112.43 kJ/mol) and the lowest (102.89 kJ/mol) activation energy of thermal decomposition, respectively. The activation energies were lower at larger amounts of sulfate groups from carrageenan on the degradation reactions. The DSC trend for all samples shows two (2) major intense peaks recorded in the DSC thermograms; an endothermic transition at temperature around 100^°C and followed by an exothermic transition at temperature around 300^°C. The endothermic transition is due to the heat absorption for dehydration of water, H2O and the decomposition of samples process. Meanwhile, the exothermic transition is caused by the formation of H₂O, CO and CH₄ in polysaccharide film from dehydration, depolymerisation and decomposition at the high-temperature stages.</p><p>Chemical Engineering Research Bulletin 19(2017) 80-86</p>

Amelogenesis Imperfecta with Distal Renal Tubular Acidosis: A Novel Syndrome?

Amelogenesis imperfecta (AI) is a heterogeneous group of inherited dental enamel defects. It has rarely been reported in association with multiorgan syndromes and metabolic disorders. The metabolic disorders that have been reported in association with AI include hypocalciuria, impaired urinary concentrating ability, and Bartter-like syndrome. In literature, only three cases of AI and distal renal tubular acidosis (dRTA) have been described: two cases in adults and a solitary case in the pediatric age group. Here, we report a child with AI presenting with dRTA; to the best of our knowledge, our reported case is the only second such case in pediatric age group. Our case highlights the importance of recognizing the possibility of renal abnormalities in patients with AI as it will affect the long-term prognosis.

Reactive transport modeling of subsurface arsenic removal systems in rural Bangladesh

Subsurface Arsenic Removal (SAR) is a technique for in-situ removal of arsenic from groundwater. Extracted groundwater is aerated and re-injected into an anoxic aquifer, where the oxygen in the injected water reacts with ferrous iron in the aquifer to form hydrous ferric oxide (HFO). Subsequent extraction of groundwater contains temporarily lower As concentrations, because As sorbs onto the HFO. Injection, storage, and extraction together is called a cycle. A reactive transport model (RTM) was developed in PHREEQC to determine the hydrogeochemical processes responsible for As (im)mobilization during experimental SAR operation performed in Bangladesh. Oxidation of Fe(II) and As(III) were modeled using kinetic-rate expressions. Cation exchange, precipitation of HFO, and surface complexation, were modeled as equilibrium processes. A best set of surface complexation reactions and corresponding equilibrium constants was adopted from previous studies to simulate all 20 cycles of a SAR experiment. The model gives a reasonable match with observed concentrations of different elements in the extracted water (e.g., the r(2) value of As was 0.59 or higher). As concentrations in the extracted water are governed by four major processes. First, As concentration decreases in response to the elevated pH of injection water and likewise increases when native neutral pH groundwater flows in. Second, the sorption capacity for As increases due to the gradual buildup of HFO. Third, As sorption is enhanced by preferential removal of As(V). Fourth, competitive sorption of Si limits the capacity of freshly precipitated HFO for As sorption. Transferability of the developed reactive transport model was demonstrated through successful application of the model, without further calibration, to two additional SAR sites in Bangladesh. This gives confidence that the model could be useful to assess potential SAR performance at locations in Bangladesh based on local hydrogeochemical conditions.

Serum levels of high sensitivity C-Reactive protein and its association with lipidemic status in Bangladeshi healthy adults

Background: Metabolic diseases are affecting human health all over the world. These chronic disease states are associated with high sensitive CRP. The present study aims to measure hsCRP and lipid levels in a group of healthy adults to work out the normal hsCRP levels and explore its relationship to lipidemic and anthropometric variables.Materials and Methods: A total of 149 adults, age 30-60 yrs, healthy subjects were recruited in this study. Vital statistics were taken along with measurement of blood glucose, triglyceride, total cholesterol, high density lipoprotein, low density lipoprotein and hsCRP levels. Data were analyzed using statistical Package for Social Program (SPSS) for Windows version 10.Results: Mean (±SD) hsCRP was 2.46±1.89 (mg/l) with a cut off value of 3mg/l. Of the total 149 subjects 102 (66.4%) and 47 (31.5%) subjects had hsCRP level below and above the cutoff respectively. Triglyceride was significantly higher (p=0.033) and HDL was lower in subjects with high hsCRP. Total cholesterol and LDL was almost similar in both groups. Binary logistic regression showed significant negative association between hsCRP and HDLc (p=0.029) and but the model excluding HDL-c showed significant positive association (p=0.03) with triglyceride.Conclusion: About one-third of healthy Bangladeshi adults may have chronic subclinical inflammation and thus may have a risk of cardiovascular disorders. More than one-third healthy Bangladeshi adults have one or more type of dyslipidemia and the subclinical chronic inflammation in healthy Bangladeshi adults has a positive association with their serum triglyceride and negative association with their HDL-cholesterol levels.DOI: http://dx.doi.org/10.3126/jpn.v4i8.11591 Journal of Pathology of Nepal; Vol.4,No. 8 (2014) 644-648

Effect of hyperglycaemia on muscarinic M3 receptor expression and secretory sensitivity to cholinergic receptor activation in islets

AIMS

Islets are innervated by parasympathetic nerves which release acetylcholine (ACh) to amplify glucose-induced insulin secretion, primarily via muscarinic M3 receptors (M3R). Here we investigate the consequence of chronic hyperglycaemia on islet M3R expression and secretory sensitivity of mouse islets to cholinergic receptor activation.

METHODS

The impact of hyperglycaemia was studied in (i) islets isolated from ob/ob mice, (ii) alginate-encapsulated mouse islets transplanted intraperitoneally into streptozotocin-induced diabetic mice and (iii) mouse and human islets maintained in vitro at 5.5 or 16 mmol/l glucose. Blood glucose levels were assessed by a commercial glucose meter, insulin content by RIA and M3R expression by qPCR and immunohistochemistry.

RESULTS

M3R mRNA expression was reduced in both ob/ob islets and islets maintained at 16 mmol/l glucose for 3 days (68 and 50% control, respectively). In all three models of hyperglycaemia the secretory sensitivity to the cholinergic receptor agonist, carbachol, was reduced by 60-70% compared to control islets. Treatment for 72 h with the irreversible PKC activator, PMA, or the PKC inhibitor, Gö6983, did not alter islet M3R mRNA expression nor did incubation with the PI3K-inhibitor, LY294002, although enhancement of glucose-induced insulin secretion by LY294002 was reduced in islets maintained at 16 mmol/l glucose, as was mRNA expression of the PI3K regulatory subunit, p85α.

CONCLUSIONS

Cholinergic regulation of insulin release is impaired in three experimental islet models of hyperglycaemia consistent with reduced expression of M3 receptors. Our data suggest that the receptor downregulation is a PKC- and PI3K-independent consequence of the hyperglycaemic environment, and they imply that M3 receptors could be potential targets in the treatment of type 2 diabetes.

Neuropathic changes in young type 2 diabetes mellitus related to high serum t-PA

Background and Aims: A substantial number of diabetic patients, diagnosed at relatively younger age, who don’t fit to typical type 2 and type 1 class of diabetes. These patients usually present with very high level of glycemia. The uniqueness of this group of patient provide the opportunity to explore the pathophysiology of nerve functional status at an early stage of diabetes. The present study was aimed to determine markers of endothelial dysfunction and evaluate nerve functional status of a group of newly diagnosed clinically uncomplicated young diabetic patients. Material and Methods: A total number of 32 (male-13 and female-19) newly diagnosed young (diabetes diagnosed under 30 yrs) were consecutively recruited from BIRDEM Out-patient department and 30 age-, BMI-matched healthy subjects with no family history of diabetes up to second generation served as controls. Serum fructosamine was measured by reduction test with NBT method. Serum C-peptide, endothelin-1 and tissue plasminogen activator (t-PA) by ELISA and von Willebrand factor (vWF) by Radial Immunodiffusion (RID) methods. Urinary albumin measured by immunoturbidimetry method. Nerve functional status was evaluated by nerve conduction velocities (NCV), distal latencies (DL), compound muscle action potential (CAMP), F wave latencies (FWL), nerve action potential (SNAP) for motor and sensory nerve as appropriate following the standard protocol. Results: Severe hyperglycemia in the diabetic group was reflected in their mean (SD) fasting C-peptide and fructosamine level. Altered endothelial dysfunction, as evidenced by significantly high tissue plasminogen activator (t-PA) (p<0.001) in the diabetic group. Albumin creatinine ratio (ACR) was almost similar in the two groups. Ulnar distal latency was similar in both the groups. But its CAMP and NCV were significantly lower in the diabetic group (p<0.02-0.001). Ulnar F wave latency were significantly higher (p=0.016) in the diabetic group. Ulnar sensory conduction parameters did not show any difference between two groups. Peroneal motor and sural sensory functional status of the diabetic subjects showed similar trend like that of ulnar motor and sensory status. Peroneal nerve motor NCV was significantly negatively correlated with fasting glucose [r=- 0.456, p=0.001]. Peroneal motor distal latency was significantly correlated with fasting fructosamine [r=0.439, p=0.012]. Fasting fructosamine showed significant negative correlation with motor peroneal NCV [r=-0.572, p=0.001], motor ulnar NCV [r=-0.468, p=0.007], both ulnar and sural sensory NAP (p=0.02 for both]. On the basis of F wave latency 53% of diabetic subjects had diabetic neuropathy and markedly higher t-PA compared to nonneuropathy groups (p=0.001). Conclusions: The data suggest that (i) Young type 2 diabetic subjects had endothelial dysfunction at the time of diagnosis even in the presence of normoalbuminuria state; (ii) Motor nerve conduction parameters are affected more than the sensory component; (iii) F wave latencies are more frequently and early to be involved in these subjects and linked to high serum t-PA. DOI: http://dx.doi.org/10.3329/bjms.v13i2.18302 Bangladesh Journal of Medical Science Vol.13(2) 2014 p.190-197

Pattern of hypothyroid cases in Bangladeshi People: A pilot study

Aims: The present study was undertaken to explore the pathological basis of hypothyroidism and it relationship to clino-biochemical features of Bangladeshi patients. Material and Methods: A total number of 47 hypothyroid patients with duration less than two years and had no other comorbid disease were consecutively recruited from BIRDEM Out-patient department. Patients having serum FT4 level <9.14 pmol/L and serum TSH >5.01 IU/ml were identified as hypothyroidism. Presence of either anti TG antibody >40 IU/ml or anti TPO antibody > 35 IU/ml or both were defined as autoimmune hypothyroidism. Thyroid gland was examined and classified according to joint criteria of WHO, UNICEF and ICCIDD criteria. Results: Female preponderance was observed in this series though small total number of samples. Familial hypothyroidism was reported in 19% of cases and 8% of patients came from iodine deficient area. Out of 47 cases autoimmune markers were done in 40 and of them 32 (68%) were positive for autoantibodies. Of the positive case 22% were positive for anti TPO antibody and 6% for anti TG antibody; 72% cases both. Drug and radiation were excluded as the cause of hypothyroidism in this series. Family history of hypothyroidism was positive in 22% and 25% autoimmune and non-autoimmune study cases. Of the autoimmune case 44% had age between 30-44 years and among non-autoimmune case 37% were 15-30 years. Eleven of 32 (34%) autoimmune hypothyroid cases presented with irregular menstrual cycle. Out of 47 hypothyroid patients in this study, 36 (77%) had palpable or enlarged thyroid gland. Of the 40 cases autoimmune status evaluated palpable among 25 (78%) autoimmune and 6 (75%) non-autoimmune hypothyroid patients. Conclusions: It is concluded that higher proportion of hypothyroid cases are of antoantibody positive. These subjects have heterogeneous phenotypic presentation. This necessitates that all newly detected hypothyroidism should be screened for autoimmune status with the same importance as given for thyroid hormone level and managed accordingly. DOI: http://dx.doi.org/10.3329/bjms.v12i4.16660 Bangladesh Journal of Medical Science Vol. 12 No. 04 October ’13 Page 405-412

Use of a tissue expander as a radio-protective spacer with a latissimus dorsi flap in the management of a peripheral primitive neuroectodermal tumour (pPNET)

Peripheral primitive neuroectodermal tumours (pPNET) are aggressive neoplasms that require radical surgical resection with adjuvant chemotherapy and radiotherapy. A pPNET of the posterior chest wall was resected with wide soft tissue margins in a 14 year old male. Following tumour excision a spacer device was positioned in the retroperitoneum adjacent to the ipsilateral left kidney displacing it from the planned radiotherapy field. A pedicled latissimus dorsi myocutaneous flap was used to achieve robust soft tissue cover. Ultrasound demonstrated anteromedial displacement of the left kidney with no hydronephrosis and renal function remained normal during subsequent radiotherapy. This report highlights the usefulness of a tissue expander in providing protection for vital structures during radiotherapy.

Plasma total homocysteine is not associated with peripheral neuropathy in a groups Bangladeshi type 2 diabetic subjects

Aims: The present study was undertaken to explore the relationship of plasma homocysteine in the pathogenesis of neuropathy in diabetic patients.Subjects and Methods: Forty two type 2 diabetic patients [22 with neuropathy (DN group) and 20 without neuropathy (DNN group)], age range between 35-70 years had relatively controlled glycemia and duration of diabetes 7-15 years, were studied. Motor and sensory nerve conduction velocities and action potential amplitudes of peripheral nerves were determined by following standard protocol. HbA1c was estimated by modified HPLC (BIO-RAD Variant, USA). Serum C-peptide was measured by enzyme linked immunosorbentassay (ELISA), plasma total homocysteine by Fluorescent Polarization Immunoassay (FPIA). Results: Age, BMI and blood pressure of the study subjects were. Duration of diabetes between DN and DNN groups was comparable. DN group had significantly higher fasting glucose levels (9.8±3.8, mmol/l) compared to the DNN group (6.9±1.8, p=0.004). This trend was also reflected in the HbA1c level: 8.7± 2.1 vs 7.2±1.6 in DN group and DNN group respectively (p=0.009). The two diabetic groups had relatively higher absolute C-peptide level compared to the controls (p=ns). DN and DNN groups had significantly higher plasma homocysteine level compared to the Controls. But between the two diabetic groups no significant difference was observed. Ulnar and peroneal motor nerve conduction velocities and compound muscle action potentials in the diabetic neuropathy group significantly lower compared to diabetic counterpart and the controls. Ulnar and sural sensory nerve conduction velocities and action potentials were significantly lower in the diabetic neuropathy group compared to the diabetic counterpart and the controls. Plasma homocysteine did not show any correlation with nerve conduction velocities  and action potential amplitudes.Conclusions: The data concluded that (i) Diabetic neuropathy may not  be related to hyperhomocysteinemia in type 2 diabetic patients of Bangladeshi origin; (ii) Hyperglycemia, even at milder level, is related to neuronal dysfunction in these subjects; and (ii) Hyperinsulinemia don't seem to be prerequisite for neuropathy in these subjects. DOI: http://dx.doi.org/10.3329/bjms.v11i4.12607 Bangladesh Journal of Medical Science Vol. 11 No. 04 Oct’12  

Contractility of ventricular myocytes is well preserved despite altered mechanisms of Ca2+ transport and a changing pattern of mRNA in aged type 2 Zucker diabetic fatty rat heart

There has been a spectacular rise in the global prevalence of type 2 diabetes mellitus and cardiovascular complications are the major cause of morbidity and mortality in diabetic patients. The objective of the study was to investigate ventricular myocyte shortening, intracellular Ca(2+) signalling and expression of genes encoding cardiac muscle proteins in the aged Zucker diabetic fatty (ZDF) rat. There was a fourfold elevation in non-fasting blood glucose in ZDF rats (478.43 ± 29.22 mg/dl) compared to controls (108.22 ± 2.52 mg/dl). Amplitude of shortening, time to peak (TPK) and time to half (THALF) relaxation of shortening were unaltered in ZDF myocytes compared to age-matched controls. Amplitude and THALF decay of the Ca(2+) transient were unaltered; however, TPK Ca(2+) transient was prolonged in ZDF myocytes (70.0 ± 3.2 ms) compared to controls (58.4 ± 2.3 ms). Amplitude of the L-type Ca(2+) current was reduced across a wide range of test potentials (-30 to +40 mV) in ZDF myocytes compared to controls. Sarcoplasmic reticulum Ca(2+) content was unaltered in ZDF myocytes compared to controls. Expression of genes encoding cardiac muscle proteins, membrane Ca(2+) channels, and cell membrane ion transport and intracellular Ca(2+) transport proteins were variously altered. Myh6, Tnnt2, Cacna2d3, Slc9a1, and Atp2a2 were downregulated while Myl2, Cacna1g, Cacna1h, and Atp2a1 were upregulated in ZDF ventricle compared to controls. The results of this study have demonstrated that preserved ventricular myocyte shortening is associated with altered mechanisms of Ca(2+) transport and a changing pattern of genes encoding a variety of Ca(2+) signalling and cardiac muscle proteins in aged ZDF rat.

Low Temperature ECR -Plasma Assisted MOCVD Microcrystalline and Amorphous GaN Deposition and Characterization for Electronic Devices

GaN films have been deposited over a range of temperatures from 50 C to 650 C by ECR plasma MOCVD on silicon (111) and (100), sapphire and quartz using triethylgallium and molecular nitrogen or ammonia as reagents. Growth rates of 2 um/hr are achieved on temperature-controlled substrates (total reactor pressure 0.5 mTorr, 250 watts at 2.45 GHz).

Films deposited at 200, 600 and 650 C on sapphire show the GaN(0002) diffraction peak and sharp photoluminescence lines (at 10 K) between 370 and 400 nm and broad emission at 530-550 nm. Broad photoluminescence at 390 nm is observed from GaN/Si( 11). Films deposited at 50 and 100 C show no evidence of a crystalline phase or GaN(0002) diffraction peak. The films are smooth and optically transparent. A broad photoluminescence peak at 520 nm, with a fwhm of about 150 nm is also observed (at 10K). The optical bandgap is measured to be about 2.6-2.7 eV. All of these films show a GaN LO phonon mode at 736 cm-l. IR spectra indicate some hydrocarbon impurities in the low temperature films.

Prototype devices (Schottky barrier diodes) have been made from MOCVD GaN and amorphous GaN.

Workplace-related burns

Introduction. The key element of a safe workplace for employees is the maintenance of fire safety. Thermal, chemical, and electrical burns are common types of burns at the workplace. This study assessed the epidemiology of work-related burn injuries on the basis of the workers treated in a regional burn centre. Methods. Two years' retrospective data (2005-2006) from the Trauma Registry of the American College of Surgeons of the Joseph M. Still Burn Center at Doctors Hospital in Augusta, Georgia, were collected and analysed. Results. During the time period studied, 2510 adult patients with acute burns were admitted; 384 cases (15%) were work-related. The average age of the patients was 37 yr (range, 15-72 yr). Males constituted the majority (90%) of workrelated burn injury admissions. The racial distribution was in accordance with the Centre's admission census. Industrial plant explosions accounted for the highest number of work-related burns and, relatively, a significant number of patients had chemical burns. The average length of hospital stay was 5.54 days. Only three patients did not have health insurance and four patients (1%) died. Conclusion. Burn injuries at the workplace predominantly occur among young male workers, and the study has shown that chemical burns are relatively frequent. This study functions as the basis for the evaluation of work-related burns and identification of the causes of these injuries to formulate adequate safety measures, especially for young, male employees working with chemicals.

Quaternary ultraviolet AlInGaN MQW laser diode performance using quaternary AlInGaN electron blocking layer

The effect of polarization-matched Al(0.25)In(0.08)Ga(0.67)N electron-blocking layer (EBL) on the optical performance of ultraviolet Al(0.08)In(0.08)Ga(0.84)N/Al(0.1)In(0.01)Ga(0.84)N multi-quantum well (MQW) laser diodes (LDs) was investigated. The polarization-matched Al(0.25)In(0.08)Ga(0.67)N electron blocking layer (EBL) was employed in an attempt to reduce the polarization effect inside the active region of the diodes. The device performance which is affected by piezoelectric was studied via drift-diffusion model for carrier transport, optical gain and losses using the simulation program of Integrated System Engineering Technical Computer Aided design (ISE TCAD). The optical performance of the LD using quaternary Al(0.25)In(0.08)Ga(0.67)N EBL was compared with the LD using ternary Al(0.3)Ga(0.7)N EBL where both materials have the same energy band gap of Eg = 3.53 eV. The self-consistent ISE-TCAD simulation program results showed that the polarization-matched quaternary Al(0.25)In(0.08)Ga(0.67)N EBL is beneficial as it confines the electrons inside the quantum well region better than ternary Al(0.3)Ga(0.7)N EBL. The results indicated that the use of Al(0.25)In(0.08)Ga(0.67)N EBL has lower threshold current and higher optical intensity than those for Al(0.3)Ga(0.7)N EBL. The effect of Al(0.25)In(0.08)Ga(0.67)N EBL thickness on the performance of LDs has also been studied. Results at room temperature indicated that lower threshold current, high slope efficiency, high output power, and high differential quantum efficiency DQE occurred when the thickness of Al(0.25)In(0.08)Ga(0.67)N EBL was 0.25 µm.