Cyclic AMP binding to a universal stress protein in Mycobacterium tuberculosis is essential for viability

Mycobacterial genomes encode multiple adenylyl cyclases and cAMP effector proteins, underscoring the diverse ways these bacteria utilize cAMP. We identified universal stress proteins (USP), Rv1636, and MSMEG_3811 in M. tuberculosis and M. smegmatis, respectively, as abundantly expressed, novel cAMP-binding proteins. Rv1636 is secreted via the SecA2 secretion system in M. tuberculosis but is not directly responsible for the efflux of cAMP from the cell. In slow-growing mycobacteria, intrabacterial concentrations of Rv1636 were equivalent to the concentrations of cAMP present in the cell. In contrast, levels of intrabacterial MSMEG_3811 in M. smegmatis were lower than that of cAMP and therefore, overexpression of Rv1636 increased levels of 'bound' cAMP. While msmeg_3811 could be readily deleted from the genome of M. smegmatis, we find that the rv1636 gene is essential for the viability of M. tuberculosis and is dependent on the cAMP-binding ability of Rv1636. Therefore, Rv1636 may function to regulate cAMP signaling by direct sequestration of the second messenger. This is the first evidence of a 'sponge' for any second messenger in bacterial signaling that would allow mycobacterial cells to regulate the available intrabacterial 'free' pool of cAMP.

Abrocitinib effect on patient-reported outcomes in patients with moderate-to-severe atopic dermatitis: Results from phase 3 studies, including the long-term extension JADE EXTEND study

BACKGROUND

Abrocitinib improved signs and symptoms of moderate-to-severe atopic dermatitis (AD) at Weeks 12 and 16 in phase 3 studies, with a manageable safety profile. Patient-reported outcomes with long-term abrocitinib treatment were not reported.

OBJECTIVE

To evaluate patient-reported outcomes with long-term abrocitinib treatment in patients with moderate-to-severe AD.

METHODS

JADE EXTEND (NCT03422822) is an ongoing, phase 3, long-term extension study that enrolled patients from previous abrocitinib AD trials. This analysis includes patients from the phase 3 trials JADE MONO-1 (NCT03349060), JADE MONO-2 (NCT03575871) and JADE COMPARE (NCT03720470) who completed the full treatment period of placebo or abrocitinib (200 or 100 mg once daily) and subsequently entered JADE EXTEND and were randomised to receive once-daily abrocitinib 200 or 100 mg. Patient-reported endpoints to Week 48 included the proportion of patients who achieved Dermatology Life Quality Index (DLQI) scores of 0/1 (no effect of AD on quality of life [QoL]) and a ≥4-point improvement in Patient-Oriented Eczema Measure (POEM) score (clinically meaningful improvement). Data cut-off: April 22, 2020.

RESULTS

Baseline DLQI mean scores were 15.4 and 15.3 in the abrocitinib 200- and 100-mg groups, respectively, which corresponded to a 'very large effect' on QoL; at Week 48, mean DLQI scores were lower with abrocitinib 200 mg (4.6; 'small effect' on QoL) and abrocitinib 100 mg (5.9; 'moderate effect' on QoL). Baseline POEM mean scores were 20.4 and 20.5 in the abrocitinib 200- and 100-mg groups, respectively; at Week 48, mean POEM scores were 8.2 and 11.0. Week 48 patient-reported responses with abrocitinib 200 mg and abrocitinib 100 mg were 44% and 34% for DLQI 0/1, and 90% and 77% for a ≥4-point reduction in POEM score.

CONCLUSION

In patients with moderate-to-severe AD, long-term abrocitinib treatment resulted in clinically meaningful improvement in patient-reported symptoms of AD, including QoL.

Low-Loss Dielectric Ink for Printed Radio Frequency and Microwave Devices

Direct write printing is restricted by the lack of dielectric materials that can be printed with high resolution and offer dissipation factors at radio frequency (RF) within the range of commercial RF laminates. Herein, we outline the development of dielectric materials with dielectric loss below 0.006 in X and Ku frequency bands (8.2-18 GHz), the range required for radio frequency and microwave applications. The described materials were designed for printability and processability, specifically a prolonged viscosity below 1000 cps and a robust cure procedure, which requires minimal heat treatment. In the first stage of this work, nonpolar ring-opening metathesis polymerization (ROMP) is demonstrated at room temperature in an open-air environment with a low-viscosity monomer, 5-vinyl-2-norbornene, using the second-generation Grubbs catalyst (G-II). Differential scanning calorimetry (DSC) was used to study how the catalyst activity is increased with heating at various stages in the reaction, which is then used as a strategy to cure the material after printing. The resulting cured poly(5-vinyl-2-norbornene) material is then characterized for dielectric and mechanical performance before and after a secondary heat treatment, which mimics processing procedures to incorporate subsequent printed conductor layers for multilayer applications. After the secondary heat treatment, the material exhibits a 55.0% reduction in the coefficient of thermal expansion (CTE), an increase in glass-transition temperature (T_g) from 32.4 to 46.1 °C, and an increased 25 °C storage modulus from 428 to 1031 MPa while demonstrating a minimal change in dielectric loss. Lastly, samples of the developed dielectric material are printed with silver overtop to demonstrate how the material can be effectively incorporated into fully printed, multilayer RF applications.

H9N2 avian influenza virus dispersal along Bangladeshi poultry trading networks

Avian influenza virus subtype H9N2 is endemic in Bangladesh's poultry population. The subtype affects poultry production and poses a potential zoonotic risk. Insufficient understanding of how the poultry trading network shapes the dissemination of avian influenza viruses has hindered the design of targeted interventions to reduce their spread. Here, we use phylodynamic analyses of haemagglutinin sequences to investigate the spatial spread and dispersal patterns of H9N2 viruses in Bangladesh's poultry population, focusing on its two largest cities (Dhaka and Chattogram) and their poultry production and distribution networks. Our analyses suggest that H9N2 subtype avian influenza virus lineage movement occurs relatively less frequently between Bangladesh's two largest cities than within each city. H9N2 viruses detected in single markets are often more closely related to viruses from other markets in the same city than to each other, consistent with close epidemiological connectivity between markets. Our analyses also suggest that H9N2 viruses may spread more frequently between chickens of the three most commonly sold types (sunali-a cross-bred of Fayoumi hen and Rhode Island Red cock, deshi-local indigenous, and exotic broiler) in Dhaka than in Chattogram. Overall, this study improves our understanding of how Bangladesh's poultry trading system impacts avian influenza virus spread and should contribute to the design of tailored surveillance that accommodates local heterogeneity in virus dispersal patterns.

Trehalose-Grafted Glycopolymer: Synthesis via the Staudinger Reaction and Capture of Mycobacteria

A new trehalose-grafted poly(2-hydroxyethyl methacrylate) (HEMA) glycopolymer was synthesized via the perfluorophenyl azide (PFPA)-mediated Staudinger reaction between poly(HEMA-co-HEMA-PFPA) and a diphenylphosphine-derivatized trehalose. The reaction occurred rapidly at room temperature without the use of any catalyst, giving the trehalose glycopolymers over 68% yield after 1 h. The grafting density of trehalose can be controlled by the copolymer composition in poly(HEMA-co-HEMA-PFPA), resulting in 6.1% (TP1) or 37% (TP2) at 10:1 and 1:1 HEMA/HEMA-PFPA feed ratio, respectively. The trehalose glycopolymer was covalently attached on glass slides or silicon wafers using a thin film of poly(HEMA-co-HEMA-PFPA) as the adhesion layer, achieved through the C-H insertion reaction of the photogenerated singlet perfluorophenyl nitrene. To demonstrate the ability of the trehalose glycopolymer to capture mycobacteria, arrays of the trehalose glycopolymer were fabricated and treated with Mycobacterium smegmatis. Results from the optical, fluorescence, and scanning electron microscopy showed that mycobacteria were indeed captured on the trehalose glycopolymer. The amount of mycobacteria captured increased with the percent trehalose in the trehalose glycopolymer and also with the concentration of the trehalose glycopolymer. In addition, the captured bacteria could be visualized by the naked eye under the illumination of a hand-held UV lamp.

Convergent evolution in the supercoiling of prokaryotic flagellar filaments

The supercoiling of bacterial and archaeal flagellar filaments is required for motility. Archaeal flagellar filaments have no homology to their bacterial counterparts and are instead homologs of bacterial type IV pili. How these prokaryotic flagellar filaments, each composed of thousands of copies of identical subunits, can form stable supercoils under torsional stress is a fascinating puzzle for which structural insights have been elusive. Advances in cryoelectron microscopy (cryo-EM) make it now possible to directly visualize the basis for supercoiling, and here, we show the atomic structures of supercoiled bacterial and archaeal flagellar filaments. For the bacterial flagellar filament, we identify 11 distinct protofilament conformations with three broad classes of inter-protomer interface. For the archaeal flagellar filament, 10 protofilaments form a supercoil geometry supported by 10 distinct conformations, with one inter-protomer discontinuity creating a seam inside of the curve. Our results suggest that convergent evolution has yielded stable superhelical geometries that enable microbial locomotion.

High threshold efficacy responses in moderate‐to‐severe atopic dermatitis are associated with additional quality of life benefits: pooled analyses of abrocitinib monotherapy studies in adults and adolescents

Background

Once‐daily abrocitinib treatment provided meaningful improvements in signs and symptoms of moderate‐to‐severe atopic dermatitis (AD) in randomized controlled studies.

Objective

To evaluate proportions of patients with responses meeting higher threshold efficacy responses than commonly used efficacy end points and to determine if these responses were associated with quality‐of‐life (QoL) benefits.

Methods

Data from a phase 2b (NCT02780167) and two phase 3 studies (NCT03349060/JADE MONO‐1; NCT03575871/JADE MONO‐2) in adult and adolescent patients (N = 942) with moderate‐to‐severe AD receiving once‐daily abrocitinib 200 mg, abrocitinib 100 mg or placebo were pooled. Commonly used (Eczema Area and Severity Index [EASI]‐75 and ≥4‐point improvement in Pruritus Numerical Rating Scale [PP‐NRS4]) and higher threshold efficacy end points (EASI‐90 to <EASI‐100, EASI‐100 or PP‐NRS0/1 response) were evaluated. Proportions of patients across Children's Dermatology Life Quality Index/Dermatology Life Quality Index (CDLQI/DLQI) band descriptors who achieved various efficacy end points were analysed.

Results

More abrocitinib‐treated patients achieved commonly used or higher threshold efficacy end points at week 12 vs. placebo. More abrocitinib‐treated patients who achieved higher threshold efficacy end points reported ‘no effect’ of AD on QoL (by CDLQI/DLQI) at week 12 vs. those who achieved commonly used but not higher threshold efficacy end points (PP‐NRS0/1 vs. PP‐NRS4 but not PP‐NRS0/1 responders [200 mg: 66.3% vs. 17.5%; 100 mg: 62.1% vs. 20.0%]; EASI‐100, EASI‐90 to <EASI‐100 vs. EASI‐75 to <EASI‐90 responders [200 mg: 67.6%, 48.9% vs. 28.8%; 100 mg: 63.2%, 48.1% vs. 36.7%]).

Conclusions

Substantial proportions of patients with moderate‐to‐severe AD receiving abrocitinib met higher threshold efficacy end points, and this was associated with meaningful additional QoL benefits compared with those who did not meet these higher efficacy thresholds. Not only do a substantial proportion of abrocitinib‐treated patients achieve higher threshold efficacy end points but they also do so in a similar timeframe as the more commonly used thresholds for efficacy end points.

Clinical trials

NCT02780167, NCT03349060 and NCT03575871.

Prevalence of Sonologically Detected Non-alcoholic Fatty liver disease Among School Children of Sylhet City

This cross sectional descriptive type of observational study was designed to see the prevalence of NAFLD among school children of Sylhet, Bangladesh from December 2019 to January 2020. School children of three private schools of Sylhet City were randomly selected. Socio-demographic data and anthropometric measurement of them were recorded. Then they underwent screening sonologically for NAFLD. Data analysis was done using SPSS version 20.0. P value <0.05 was taken as significant. Total 174 students, boys 99(56.9%) and girls 75(43.1%) were included. Age of them varied from nine years to 17 years (mean 13.408). In this series 82(47.1%), 52(29.9%) and 40(23.0%) were of normal weight, overweight and obese children respectively. In this study 29(16.7%) children had NAFLD and seven (4.0%) had biliary sludge in gall bladder. NAFLD was significantly higher among children with higher BMI (p=0.00). Female sex, children consuming fast food and playing video games were about two times more prone to develop NAFLD. Biliary sludge was found significantly higher among children consuming fast food (p=0.02). NAFLD among school going children is not uncommon. Higher BMI is a significant risk factor of developing NAFLD. Girls and children consuming fast food and playing video games also are more prone to develop NAFLD. Prevalence of sludge in gall bladder is low among school children.

Can paraoxonase activity serve as a comparable marker than high density lipoprotein in the follow-up of patients of coronary artery disease?

Funding Acknowledgements

Type of funding sources: None.

Background

Human serum paraoxonase (PON1) produced by the liver and residing almost exclusively on high density lipoproteins (HDL), has been demonstrated to prevent the oxidation of low density lipoprotein (LDL), which is  the central initiating factor in the causation of atherosclerosis. (1,2) Thus, PON1 along with HDL, plays an important role in the pathophysiology of atherosclerosis and consequently coronary artery disease. Statins are commonly used in clinical practice for the management of dyslipidemia , a known risk factor for coronary artery disease (CAD).Keeping this in mind,  it was deemed necessary to set up an observational study to explore whether the changes in PON1 activity after 3 months of statin therapy could help in the follow up of CAD patients.

Purpose

The purpose of the study was to evaluate the alterations in the PON1 activity along with the concentrations of HDL and LDL in patients of CAD before and after 3 months of statin therapy and to explore whether PON1 can be used as a comparable marker for assessment of the atherosclerotic risk in the follow up of these patients.

Materials and Methods

The study included 30 new patients who were put on statin therapy following the diagnosis of acute coronary syndrome in the Cardiology outpatients department. The activity of PON1 and the lipid profile parameters were estimated before starting statin therapy and again three months later. Patients with co-morbidities like diabetes, chronic kidney disease, chronic liver disease and other cardiac diseases of infectious etiology were excluded from the study. The data thus obtained was compiled and tabulated in Excel and statistically analyzed.

Results

The mean, median and standard deviation of the PON1, LDL and HDL, both before and after starting statin therapy, were calculated and the distribution of the individual parameters were determined. Analysis of the compiled data revealed that there was a statistically significant increase in both PON1 (p &lt; 0.05) and HDL (p &lt; 0.001) and a decrease (p &lt;0.05, also statistically significant) in LDL after 3 months of statin therapy. The results both before and after 3 months of statin therapy are summarised in the table attached.(Table 1)

Conclusion

It may be concluded from the above study that the activity of PON1 may be used to indicate the changes in the lipid profile in the follow up of patients of CAD being treated with statins. It is however necessary to conduct larger, well designed studies in future to explore whether it may be used as a comparable marker better than HDL in the follow up of these patients. Abstract Figure.

Multifunctional Thio-Stabilized Gold Nanoparticles for Near-Infrared Fluorescence Detection and Imaging of Activated Caspase-3

Background

Gold nanoparticles (AuNPs) are commonly used in nanomedicine because of their unique spectral properties, chemical and biological stability, and ability to quench the fluorescence of organic dyes attached to their surfaces. However, the utility of spherical AuNPs for activatable fluorescence sensing of molecular processes have been confined to resonance-matched fluorophores in the 500 nm to 600 nm spectral range to maximize dye fluorescence quenching efficiency. Expanding the repertoire of fluorophore systems into the NIR fluorescence regimen with emission >800 nm will facilitate the analysis of multiple biological events with high detection sensitivity.

Objective

The primary goal of this study is to determine if spherical AuNP-induced radiative rate suppression of non-resonant near-infrared (NIR) fluorescent probes can serve as a versatile nanoconstruct for highly sensitive detection and imaging of activated caspase-3 in aqueous media and cancer cells. This required the development of activatable NIR fluorescence sensors of caspase-3 designed to overcome the nonspecific degradation and release of the surface coatings in aqueous media.

Method

We harnessed the fluorescence-quenching properties and multivalency of spherical AuNPs to develop AuNP-templated activatable NIR fluorescent probes to detect activated caspase-3, an intracellular reporter of early cell death. Freshly AuNPs were coated with a multifunctional NIR fluorescent dye-labeled peptide (LS422) consisting of an RGD peptide sequence that targets α_vβ₃-integrin protein (α_vβ₃) on the surface of cancer cells to mediate the uptake and internalization of the sensors in tumor cells; a DEVD peptide sequence for reporting the induction of cell death through caspase-3 mediated NIR fluorescence enhancement; and a multidentate hexacysteine sequence for enhancing self-assembly and stabilizing the multifunctional construct on AuNPs. The integrin binding affinity of LS422 and caspase-3 kinetics were determined by a radioligand competitive binding and fluorogenic peptide assays, respectively. Detection of intracellular caspase-3, cell viability, and the internalization of LS422 in cancer cells were determined by confocal NIR fluorescence spectroscopy and microscopy.

Results

Narrow size AuNPs (13 nm) were prepared and characterized by transmission electron microscopy and dynamic light scattering. When assembled on the AuNPs, the binding constant of LS422 for α_vβ₃ improved 11-fold from 13.2 nM to 1.2 nM. Whereas the catalytic turnover of caspase-3 by LS422-AuNPs was similar to the reference fluorogenic peptide, the binding affinity for the enzyme increased by a factor of 2. Unlike the α_vβ₃ positive, but caspase-3 negative breast cancer MCF-7 cells, treatment of the α_vβ₃ and caspase-3 positive lung cancer A549 cells with Paclitaxel showed significant fluorescence enhancement within 30 minutes, which correlated with caspase-3 specific activation of LS422-AuNPs fluorescence. Incorporation of a 3.5 mW NIR laser source into our spectrofluorometer increased the detection sensitivity by an order of magnitude (limit of detection ~0.1 nM of cypate) and significantly decreased the signal noise relative to a xenon lamp. This gain in sensitivity enabled the detection of substrate hydrolysis at a broad range of inhibitor concentrations without photobleaching the cypate dye.

Conclusion

The multifunctional AuNPs demonstrate the use of a non-resonant quenching strategy to design activatable NIR fluorescence molecular probes. The nanoconstruct offers a selective reporting method for detecting activated caspase-3, imaging of cell viability, identifying dying cells, and visualizing the functional status of intracellular enzymes. Performing these tasks with NIR fluorescent probes creates an opportunity to translate the in vitro and cellular analysis of enzymes into in vivo interrogation of their functional status using deep tissue penetrating NIR fluorescence analytical methods.

A Portable Micro-Gas Chromatography with Integrated Photonic Crystal Slab Sensors on Chip

The miniaturization of gas chromatography (GC) systems has made it possible to utilize the analytical technique in various on-site applications to rapidly analyze complex gas samples. Various types of miniaturized sensors have been developed for micro-gas chromatography (µGC). However, the integration of an appropriate detector in µGC systems still faces a significant challenge. We present a solution to the problem through integration of µGC with photonic crystal slab (PCS) sensors using transfer printing technology. This integration offers an opportunity to utilize the advantages of optical sensors, such as high sensitivity and rapid response time, and at the same time, compensate for the lack of detection specificity from which label-free optical sensors suffer. We transfer printed a 2D defect free PCS on a borofloat glass, bonded it to a silicon microfluidic gas cell or directly to a microfabricated GC column, and then coated it with a gas responsive polymer. Realtime spectral shift in Fano resonance of the PCS sensor was used to quantitatively detect analytes over a mass range of three orders. The integrated µGC–PCS system was used to demonstrate separation and detection of a complex mixture of 10 chemicals. Fast separation and detection (4 min) and a low detection limit (ng) was demonstrated.

Confinement driven anomalous freezing in nano porous spray dried microspheres

One-step evaporative jamming of colloidal silica particles in contact-free spray droplets resulted in well-defined powder micro-granules with interstitial nanopores. This paper reports the anomalous freezing behaviour of confined water in the microspheres synthesized using spray drying. It has been revealed that the freezing point of water in these microspheres gets significantly lowered (∼-45 °C) owing to the confinement effect. Thermoporometry results are corroborated with the structural details obtained using complementary techniques of gas adsorption measurements and small-angle x-ray scattering.

POS0678 DOES SILDENAFIL IMPROVE ENDOTHELIAL DYSFUNCTION IN RHEUMATOID ARTHRITIS? – A PILOT CLINICAL TRIAL

Background:

Rheumatoid arthritis (RA) is independently associated with an increased risk of cardiovascular disease (CVD). One of the early stages of atherosclerosis is endothelial dysfunction, which is increased in RA. Using drugs to target endothelial dysfunction is a promising novel strategy for CVD prevention in RA. Sildenafil has been shown to improve endothelial function in diabetics, who have similar increased CVD risk. Our hypothesis was that sildenafil use may be a novel primary CVD prevention strategy in RA.

Objectives:

To determine if sildenafil use in RA patients improves endothelial dysfunction (as measured by brachial artery flow-mediated dilation [FMD] and peripheral arterial tone [PAT]), as well as serum inflammatory and atherosclerosis biomarkers.

Methods:

This NIH-funded study was a phase II, randomized double-blind placebo-controlled crossover efficacy trial of 25 RA patients, with no known history of CVD, but at least one traditional CVD risk factor. Patients were randomized 1:1 to receive either sildenafil or placebo for 3 months, then after a 2-week washout, crossed over to each respective group for an additional 3 months. Vascular studies (FMD and PAT) and serum atherosclerosis biomarkers (e-Selectin, ICAM-1, VCAM-1) were performed at baseline, 3 months pre- and post-washout, and 6 months. Adverse events were collected. Given the cross-over design, analyses included a random effects model for within-subject comparisons of sildenafil versus placebo periods, adjusting for the baseline (FMD or EndoPAT) within that period and a term for treatment order. All tests were 2-sided with α=0.05.

Results:

A total of 233 subjects were assessed for eligibility, with 25 subjects being randomized after written informed consent. A total of 13 subjects were randomized to placebo first, and 12 to sildenafil first. Baseline characteristics were similar between those randomized to Placebo vs. Sildenafil first. Mean age was 62.0+/-10.9 years; 84% were female; and 92% were white. A total of 6 adverse events experienced in 3 subjects occurred. The primary endpoint (increase in %FMD in Sildenafil period vs. Placebo period) was not significant (p=0.19). However, note the study was powered at 80% to detect an effect size of 0.37 for change in %FMD or biomarker with a sample size of 60, not 25. However, sildenafil use was associated with a significant increase (improvement) by 0.200 units of PAT ratio (p=0.003) compared with placebo, adjusted by treatment order and baseline PAT ratio (within the given treatment period). Exploratory linear mixed models comparing e-Selectin, ICAM-1, and VCAM-1 between Sildenafil vs. Placebo periods, adjusted for treatment order and the baseline biomarker level, did not show any significant differences except for ICAM-1 (55.3 units higher in Sildenafil vs. Placebo periods, p=0.011).

Conclusion:

In this pilot trial of 25 RA subjects, sildenafil use was associated with a significant increase (improvement) in endothelial function as measured by PAT. However, there was no significant difference in FMD. The study is limited due to the small sample size, which was impacted by slow recruitment as well as the COVID-19 pandemic. Future larger studies are required to assess whether other PDE5 inhibitors may improve endothelial dysfunction in RA and other autoimmune disease patients at high risk of CVD.

References:

[1]Maradit-Kremers H, Crowson CS, Nicola PJ, et al. Increased unrecognized coronary heart disease and sudden deaths in rheumatoid arthritis: a population-based cohort study. Arthritis Rheum 2005;52:402-11.

[2]Peters MJ, van Halm VP, Voskuyl AE, et al. Does rheumatoid arthritis equal diabetes mellitus as an independent risk factor for cardiovascular disease? A prospective study. Arthritis Rheum 2009;61:1571-9.

[3]Deyoung L, Chung E, Kovac JR, et al. Daily use of sildenafil improves endothelial function in men with type 2 diabetes. J Andrology 2012;33:176-80.

Disclosure of Interests:

None declared

A study on effect of phototherapy on platelet count in neonates with unconjugated hyperbilirubinemia: a hospital based prospective observational study

Background: Thrombocytopenia as a side effect of phototherapy has not been mentioned in standard literature and textbooks. Though there are few studies in this regard, but results are conflicting. Aims and Objective: Hence, the present study is undertaken to find out whether any significant change in platelet count occurs following phototherapy, and if there be any, to see whether the changes are transient or not. Materials and Methods: This prospective and observational study was carried out over a period of one and half years (1st March 2019 to 31st August 2020) on 190 new-borns admitted with idiopathic unconjugated hyperbilirubinemia needing phototherapy through consecutive enrolment. Serum bilirubin (total, conjugated and unconjugated) and platelet count were done before initiation and just after completion of phototherapy, and seven days after completion of phototherapy. Appropriate statistical tests were used to make statistical comparisons with a p-value of < 0.05 taken as significant. Results: Among 190 neonates, 108(56.8%) were male and 82(43.2%) were female; 90(47.4%) were preterm and 100(52.6%) were term. Mean birth weight was (2.4725 ± 0.4782) kg. Mean gestational age was (36.4316 ± 2.4802) weeks. Mean haemoglobin level was (17.3816± 1.0784) gm/dl. Mean age at presentation was (4.5737± 1.5811) days. Mean total serum bilirubin (TSB) before initiation, after completion, and 7 days after completion of phototherapy were (17.8595 ± 3.7034) mg/dl, (8.1726 ± 2.2586) mg/dl and (5.7279± 1.5918) mg/dl respectively. The mean duration of phototherapy required was (48.1895 ± 13.6054) hours. Mean platelet count before initiation and just after completion of phototherapy were (2,49,321.0526± 89,460.2101)/μL and (2,22,436.8421 ± 88,538.7173)/μL respectively. Mean platelet count 7days after completion of phototherapy was (2,46,210.5263 ± 87,442.3038)/μL. Decrease in platelet count just after completion of phototherapy was statistically significant. Fifty-nine (31.1%) out of 190 neonates developed mild thrombocytopenia (100000- <150000/μL) just after completion of phototherapy, but none developed moderate or severe thrombocytopenia. None having thrombocytopenia manifested with clinical bleed. Platelet count raised near to pre-phototherapy level 7 days after completion of phototherapy. Fall in platelet count was found to have a positive association with increased duration of phototherapy and lower gestational age (p<0.0001). However, there was no statistically significant association (p>0.05) between reduction in platelet count with gender. Conclusions: Though the incidence of thrombocytopenia following phototherapy was significant, but it was mostly mild and transient, and clinically insignificant. There was significant association between decrease of platelet count with duration of phototherapy and lower gestational age.

Mycobacterial STAND adenylyl cyclases: The HTH domain binds DNA to form biocrystallized nucleoids

Mycobacteria harbor a unique class of adenylyl cyclases with a complex domain organization consisting of an N-terminal putative adenylyl cyclase domain fused to a nucleotide-binding adaptor shared by apoptotic protease-activating factor-1, plant resistance proteins, and CED-4 (NB-ARC) domain, a tetratricopeptide repeat (TPR) domain, and a C-terminal helix-turn-helix (HTH) domain. The products of the rv0891c-rv0890c genes represent a split gene pair, where Rv0891c has sequence similarity to adenylyl cyclases, and Rv0890c harbors the NB-ARC-TPR-HTH domains. Rv0891c had very low adenylyl cyclase activity so it could represent a pseudoenzyme. By analyzing the genomic locus, we could express and purify Rv0890c and find that the NB-ARC domain binds ATP and ADP, but does not hydrolyze these nucleotides. Using systematic evolution of ligands by exponential enrichment (SELEX), we identified DNA sequences that bound to the HTH domain of Rv0890c. Uniquely, the HTH domain could also bind RNA. Atomic force microscopy revealed that binding of Rv0890c to DNA was sequence independent, and binding of adenine nucleotides to the protein induced the formation of higher order structures that may represent biocrystalline nucleoids. This represents the first characterization of this group of proteins and their unusual biochemical properties warrant further studies into their physiological roles in future.

Variety-specific arsenic accumulation in 44 different rice cultivars (O. sativa L.) and human health risks due to co-exposure of arsenic-contaminated rice and drinking water

Arsenic (carcinogenic) is a global health concern due to its presence in groundwater and subsequent accumulation in cultivated-rice via irrigation. The present work focused on the evaluation of arsenic concentration in groundwater, different cultivated-rice varieties (studied together for the first-time) and related health-risks. Arsenic in groundwater (0.26-0.73 mg/L) exceeded the World Health Organization limit for drinking water (0.01 mg/L). Arsenic concentration in rice-grains was found in the range: < 0.0003-2.6 mg/kg dry-weights, where 42 rice varieties (out of total 44) exceeded the Codex Alimentarius Commission limit of polished-rice (0.2 mg/kg). The variety-specific differential-response of arsenic-accumulation was observed (first-time report), where high yielding rice varieties (HYV) were more prone to accumulate arsenic in comparison to local varieties (LV), however, 'Radhunipagol' (an aromatic LV) exhibited as a moderate arsenic-accumulator (BCF = 2.8). The cumulative estimated-daily-intakes (EDI_Cumulative) of arsenic in central-tendency-exposure were observed to be 0.029, 0.031 and 0.04 mg/kg-day among children, teenagers and adults, respectively. The EDI_Cumulative for possible reasonable-maximum-exposure among the above mentioned subpopulation was 0.038, 0.04 and 0.05 mg/kg-day, respectively. The evaluated Cumulative Hazard Index and Individual Excess Lifetime Cancer Risk values suggested that the studied population is under extremely severe cancerous and noncancerous risks to arsenic co-exposures via drinking water and rice.

E-cadherin Gene (CDH1) Expression in Low Grade Astrocytoma

Astrocytoma is the commonest primary brain tumor. These are feared due to their invasiveness in brain parenchyma so are less amenable to surgical removal and current chemotherapy regimens with a high mortality rate. Cell adhesion molecule (CAM) E-cadherin (CDH1) downregulation has been associated with tumors of different system and organs featuring invasion and metastasis. Therefore, the aim of the study was to find out the level of E-cadherin gene expression in low grade astrocytoma. In this cross-sectional study, 22 formalin fixed paraffin embedded tissue were taken as cases. Three non tumorous brain tissue and 1fresh post-mortem brain tissue were taken as control. Histological features were studied under light microscope with Haematoxylin and Eosin (H&E stain). Expression of CDH1 gene was analyzed by real time - polymerase chain reaction (RT-PCR) by comparative cyclic threshold (Ct) value method. The change in E-cadherin expression was measured by fold change in comparison with the control brain tissue. The data was tabulated and statistical analysis was performed. Among the 22 study cases 8(36.36%) were World Health Organization (WHO) Grade I and 14(63.63%) were WHO Grade II. All tumors showed downregulation of CDH1 gene in comparison with non-tumorous control tissue. The result is statistically significant (p=0.019). So, the study data revealed that downregulation of E-cadherin gene occurs in low grade astrocytoma and tumors of WHO Grade II showed more downregulation than Grade I tumors.

A multi-centre, cross-sectional study on coronavirus disease 2019 in Bangladesh: clinical epidemiology and short-term outcomes in recovered individuals

Coronavirus disease 2019 (COVID-19) rapidly became a global pandemic. This study aimed to investigate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) -associated epidemiology and clinical outcomes in Bangladesh in order to understand the future course of the COVID-19 pandemic and develop approaches to prevention. A cross-sectional study based on retrospective interviews was conducted on 1021 individuals with RT-PCR-confirmed COVID-19 admitted in six different hospitals in Bangladesh and who recovered 4 weeks before the interview date. Of the 1021 patients, 111 (10.9%) were asymptomatic and the other 910 (89.1%) were symptomatic. Higher prevalence of COVID-19 was found in the male population (75%), in cohorts with B-positive blood group (36.3%) and in the 31-40 years age group. Common symptoms observed in our study participants were fever (72.4%), cough (55.9%), loss of taste (40.7%) and body ache (40%); whereas among the biochemical parameters, neutrophil count (46.4%), D-dimer (46.1%) and ferritin (37.9%) levels were elevated. Among the recovered individuals, short-term outcomes including pains and aches (31.8%), weakened attention span (24.4%) and anxiety or depression (23.1%) were also significantly prevalent in the symptomatic cases with comorbidities. Our study showed that in Bangladesh, adult males aged between 31 and 40 years were more vulnerable to developing COVID-19. It also indicated a rising trend of asymptomatic cases as the pandemic progressed. As a consequence, deployment of interventions to curb further spread of community infection is necessary to avoid grave outcomes of COVID-19 in Bangladesh.

Integrated ozonation assisted electrocoagulation process for the removal of cyanide from steel industry wastewater

This work focuses on the removal of cyanide, chemical oxygen demand (COD), biological oxygen demand (BOD), and chloride from biological oxidation treated (BOT) effluent of the steel industry by integrated ozonation assisted electrocoagulation method. The removal efficiency of the pollutants was found to be inefficient when the electrocoagulation or ozonation process was performed separately. However, a combination of ozonation and electrocoagulation gives a highly satisfactory result. Such an integrated approach for the treatment of BOT effluent has not been previously investigated. The effects of operating variables viz. ozone generation rate, current density, and analysis time on pollutant removal were primarily analyzed for the hybrid process. The experimental operating condition was optimized and was seen that ozone generation rate of 1.33 mg s^-1, ozonation time of 40 min, a current density of 100 A m^-2, and electrolysis time of 30 min were sufficient for reducing the pollutant concentration below its permissible limits. The removal efficiencies of the combined process at optimum conditions were 99.8%, 94.7%, 95%, and 46.5% for cyanide, COD, BOD, and chloride ions, respectively. A kinetic study was performed for the degradation of the pollutants during ozonation. The pseudo-first-order kinetic model was found to be best suited for the analysis with the highest R² value of 0.99 for cyanide, COD, BOD, and chloride, respectively. The mass transfer study conducted further showed that the volumetric mass transfer coefficient, K_la, was increased with that of the ozone generation rate. Cost estimation of the hybrid process was done and compared with that of the other reported integrated process.

Direct genital manipulation is rare a manifestation of childhood gratification behaviour below 5 years of age: A case series

Childhood masturbation/self-gratification behaviour means self-stimulation of the genitals by an immature child. Literature on this topic is scarce and scattered. Though most of the paediatricians seem to know about this entity, precise knowledge on spectrum of different behavioural patterns these children may show is lacking. Masturbatory activity in infants and young children is difficult to recognise because it often does not involve manual stimulation of the genitalia at all. We hereby report a series of 3 cases of childhood masturbation where direct genital manipulation, a very rare manifestation, was evident during gratification spells.

Utilization of LD slag from steel industry for the preparation of MF membrane

This work is focused on utilizing the solid waste generated from steel industry for the fabrication of porous ceramic membrane from Linz Donawitz (LD) slag. Membranes were fabricated using uniaxial method sintered at three different temperatures like 650 °C, 850 °C and 950 °C. Membranes fabricated with raw LD slag gave a highly basic filtrate. In contrast with this issue, LD slag was modified using acetic acid and CO₂ purging to convert calcium oxide which is present in the slag to calcium carbonate. The membranes fabricated from modified LD slag showed a filtrate pH of 8.4 and 8.5. Porosity, pore size distribution, flexural strength, chemical stability was determined and pure water flux experiments were conducted to evaluate the efficiency of the prepared membranes. Considering the raw materials cost, the cost of the fabricated membranes was estimated in the range of 32.55-55.7 USD/m². This work gives a potential path to develop microfiltration ceramic membrane with, high porosity and great quality in terms of strength and chemical stability. The fabricated membranes were utilized in a hybrid technique (flocculation followed by microfiltration) for the treatment of cold roll mill (CRM) wastewater generated from steel industry. Use of LD slag for the fabrication of ceramic membrane is not only an appealing option towards the commercialization of membrane, yet also great option to reduce the solid waste which is dumped to the environment.

A universal stress protein in Mycobacterium smegmatis sequesters the cAMP-regulated lysine acyltransferase and is essential for biofilm formation

Universal stress proteins (USPs) are present in many bacteria, and their expression is enhanced under various environmental stresses. We have previously identified a USP in Mycobacterium smegmatis that is a product of the msmeg_4207 gene and is a substrate for a cAMP-regulated protein lysine acyltransferase (KATms; MSMEG_5458). Here, we explored the role of this USP (USP4207) in M. smegmatis and found that its gene is present in an operon that also contains genes predicted to encode a putative tripartite tricarboxylate transporter (TTT). Transcription of the TTT-usp4207 operon was induced in the presence of citrate and tartrate, perhaps by the activity of a divergent histidine kinase-response regulator gene pair. A usp4207-deleted strain had rough colony morphology and reduced biofilm formation compared with the WT strain; however, both normal colony morphology and biofilm formation were restored in a Δusp4207Δkatms strain. We identified several proteins whose acetylation was lost in the Δkatms strain, and whose transcript levels increased in M. smegmatis biofilms along with that of USP4207, suggesting that USP4207 insulates KATms from its other substrates in the cell. We propose that USP4207 sequesters KATms from diverse substrates whose activities are down-regulated by acylation but are required for biofilm formation, thus providing a defined role for this USP in mycobacterial physiology and stress responses.

Do children use language structure to discover the recursive rules of counting?

We test the hypothesis that children acquire knowledge of the successor function - a foundational principle stating that every natural number n has a successor n + 1 - by learning the productive linguistic rules that govern verbal counting. Previous studies report that speakers of languages with less complex count list morphology have greater counting and mathematical knowledge at earlier ages in comparison to speakers of more complex languages (e.g., Miller & Stigler, 1987). Here, we tested whether differences in count list transparency affected children's acquisition of the successor function in three languages with relatively transparent count lists (Cantonese, Slovenian, and English) and two languages with relatively opaque count lists (Hindi and Gujarati). We measured 3.5- to 6.5-year-old children's mastery of their count list's recursive structure with two tasks assessing productive counting, which we then related to a measure of successor function knowledge. While the more opaque languages were associated with lower counting proficiency and successor function task performance in comparison to the more transparent languages, a unique within-language analytic approach revealed a robust relationship between measures of productive counting and successor knowledge in almost every language. We conclude that learning productive rules of counting is a critical step in acquiring knowledge of recursive successor function across languages, and that the timeline for this learning varies as a function of count list transparency.

Molecular characterization of Bu-1 and TLR2 gene in Haringhata Black chicken

Haringhata Black is the only registered indigenous poultry genetic resource of West Bengal till date. Molecular characterization of HB revealed that Bu-1 to be highly glycoylated transmembrane protein unlike mammalian Bu-1, whereas TLR2 of HB chicken was observed to be rich in Leucine rich repeat. HB chicken was observed to be genetically close to chicken of Japan, while distant to chicken breed of UK and Chicago. Avian species wise evolution study indicates genetic closeness of HB chicken with turkey. Differential mRNA expression profile for the immune response genes (TLR2, TLR4 and Bu1 gene) were studied for HB chicken with respect to other chicken breed and poultry birds, which reveals that HB chicken were better in terms of B cell mediated immunity and hence better response to vaccination. Hence HB chicken is one of the best poultry genetic resources to be reared under backyard system where biosecurity measures are almost lacking.

Spectroscopic Studies of Asparaginyl-tRNA Synthetase from Entamoeba histolytica

BACKGROUND

Aminoacyl-tRNA synthetases play an important role in catalyzing the first step in protein synthesis by attaching the appropriate amino acid to its cognate tRNA which then transported to the growing polypeptide chain. Asparaginyl-tRNA Synthetase (AsnRS) from Brugia malayi, Leishmania major, Thermus thermophilus, Trypanosoma brucei have been shown to play an important role in survival and pathogenesis. Entamoeba histolytica (Ehis) is an anaerobic eukaryotic pathogen that infects the large intestines of humans. It is a major cause of dysentery and has the potential to cause life-threatening abscesses in the liver and other organs making it the second leading cause of parasitic death after malaria. Ehis-AsnRS has not been studied in detail, except the crystal structure determined at 3 Å resolution showing that it is primarily α-helical and dimeric. It is a homodimer, with each 52 kDa monomer consisting of 451 amino acids. It has a relatively short N-terminal as compared to its human and yeast counterparts.

OBJECTIVE

Our study focusses to understand certain structural characteristics of Ehis-AsnRS using biophysical tools to decipher the thermodynamics of unfolding and its binding properties.

METHODS

Ehis-AsnRS was cloned and expressed in E. coli BL21DE3 cells. Protein purification was performed using Ni-NTA affinity chromatography, following which the protein was used for biophysical studies. Various techniques such as steady-state fluorescence, quenching, circular dichroism, differential scanning fluorimetry, isothermal calorimetry and fluorescence lifetime studies were employed for the conformational characterization of Ehis-AsnRS. Protein concentration for far-UV and near-UV circular dichroism experiments was 8 µM and 20 µM respectively, while 4 µM protein was used for the rest of the experiments.

RESULTS

The present study revealed that Ehis-AsnRS undergoes unfolding when subjected to increasing concentration of GdnHCl and the process is reversible. With increasing temperature, it retains its structural compactness up to 45ºC before it unfolds. Steady-state fluorescence, circular dichroism and hydrophobic dye binding experiments cumulatively suggest that Ehis-AsnRS undergoes a two-state transition during unfolding. Shifting of the transition mid-point with increasing protein concentration further illustrate that dissociation and unfolding processes are coupled indicating the absence of any detectable folded monomer.

CONCLUSION

This article indicates that GdnHCl induced denaturation of Ehis-AsnRS is a two - state process and does not involve any intermediate; unfolding occurs directly from native dimer to unfolded monomer. The solvent exposure of the tryptophan residues is biphasic, indicating selective quenching. Ehis-AsnRS also exhibits a structural as well as functional stability over a wide range of pH.

Assessment of Number and Distribution of Mast Cell in Oral Squamous Cell Carcinoma in Biopsy Specimen and Its Correlation with Histological Grading

Oral cancer is a commonly occurring one worldwide. More than 90% of all oral cancers are squamous cell carcinoma (SCC). The molecular biological markers of oral SCC have been extensively studied to aid in prevention and prognosis. However, no marker has been universally accepted so far. Mast cells are important component of cancer stromal interaction. Their early recruitment in tumor microenvironment and multifarious function make them a burning topic of interest in the field of research. So mast cell may act as a new target for the adjuvant treatment of oral SCC. Therefore, the aim of the study was to compare the number and distribution of mast cell between different grades of oral SCC. In this cross sectional study the sample size was 100. After routine tissue processing and staining with Hematoxylin & Eosin (H/E) stains, slides of all cases were grouped as- well, moderate and poorly differentiated invasive squamous cell carcinoma according to Anneroth's grading system. Identification of mast cell was done by Toluidine blue stain. Distribution of mast cells was observed and number of mast cells was counted. The data was tabulated and statistical analysis was performed. Out of 100 cases, 66% patients belonged to Grade I, 28% Grade II and 6% Grade III. The mean±SD number of mast cells was 3.28±1.21, 1.59±0.58 and 0.44±0.17 in Grade I, Grade II and Grade III SCC, respectively. The p value was found to be highly significant (p<0.001). An inverse significant Pearson's correlation was found between number of mast cells and grades of oral SCC. The number of mast cell was slightly increased in oral SCC cases than normal. The number of mast cells also had an inverse association with histologic grade. So, in this observation mast cell is a good cellular indicator of tumor grade.

Anisotropic interaction driven surface modulation on spray-dried microgranules

Rapid evaporation of solvent from spray colloidal droplets induces directed self-assembly among the nanoparticles, eventually interlocking them into correlated granular structures. In this work, it is demonstrated that anisotropy in colloidal interparticle interaction plays a key role in governing the surface topology of spray-dried granules. Colloidal dispersion comprised of spherical nanosilica (NS) and cylindrical carbon nanotubes (CNT) was chosen as a model system in this regard. For identical polarities of the colloidal components, granules with prominent wrinkle-like modulations are obtained, which is in drastic contrast with the case of opposite polarities. The extent of surface modulation depends on the relative concentration of CNT with respective to NS. A plausible mechanism for the formation of surface modulation is elucidated on the basis of the evolving anisotropic interparticle interactions during assembly. Electron microscopy, small-angle scattering, Raman spectroscopic techniques have been used for quantitative characterization of these micro-granules.

Mycobacterial phenolic glycolipid synthesis is regulated by cAMP-dependent lysine acylation of FadD22

The mycobacterial cell envelope is unique in its chemical composition, and has an important role to play in pathogenesis. Phthiocerol dimycocerosates (PDIMs) and glycosylated phenolphthiocerol dimycocerosates, also known as phenolic glycolipids (PGLs), contribute significantly to the virulence of Mycobacterium tuberculosis. FadD22 is essential for PGL biosynthesis. We have recently shown in vitro that FadD22 is a substrate for lysine acylation by a unique cAMP-dependent, protein lysine acyltransferase found only in mycobacteria. The lysine residue that is acylated is at the active site of FadD22. Therefore, acylation is likely to inhibit FadD22 activity and reduce PGL biosynthesis. Here, we show accumulation of PGLs in a strain of M. bovis BCG deleted for the gene encoding the cAMP-dependent acyltransferase, katbcg, with no change seen in PDIM synthesis. Complementation using KATbcg mutants that are deficient in cAMP-binding or acyltransferase activity shows that PGL accumulation is regulated by cAMP-dependent protein acylation in vivo. Expression of FadD22 and KATbcg mutants in Mycobacterium smegmatis confirmed that FadD22 is a substrate for lysine acylation by KATbcg. We have therefore described a mechanism by which cAMP can regulate mycobacterial virulence as a result of the ability of this second messenger to modulate critical cell wall components that affect the host immune response.