Structural Models for a Series of Allosteric Inhibitors of IGF1R Kinase

The allosteric inhibition of Insulin-like Growth Factor Receptor 1 Kinase (IGF1RK) is a potential strategy to overcome selectivity barriers in targeting receptor tyrosine kinases. We constructed structural models of a series of 12 indole-butyl-amine derivatives which have been reported as allosteric inhibitors of IGF1RK. We further studied dynamics and interactions of each inhibitor in the allosteric pocket via all-atom explicit-solvent molecular dynamics (MD) simulations. We discovered that a bulky carbonyl substitution at the R1 indole ring is structurally unfavorable for inhibitor binding in the IGF1RK allosteric pocket. Moreover, we found that the most potent derivative (termed C11) acquires a distinct conformation, forming an allosteric pocket channel with better shape complementarity and interactions with the receptor. In addition to a hydrogen bonding interaction with V1063, the cyano derivative C11 forms a stable hydrogen bond with M1156, which is responsible for its unique binding conformation in the allosteric pocket. Our findings show that the position of chemical substituents at the R1 indole ring with different pharmacophore features influences molecular interactions and binding conformations of the indole-butyl-amine derivatives, hence dramatically affecting their potencies. Our results provide a structural framework for the design of allosteric inhibitors with improved affinities and specificities against IGF1RK.

Molecular basis for differential recognition of an allosteric inhibitor by receptor tyrosine kinases

Understanding kinase-inhibitor selectivity continues to be a major objective in kinase drug discovery. We probe the molecular basis of selectivity of an allosteric inhibitor (MSC1609119A-1) of the insulin-like growth factor-I receptor kinase (IGF1RK), which has been shown to be ineffective for the homologous insulin receptor kinase (IRK). Specifically, we investigated the structural and energetic basis of the allosteric binding of this inhibitor to each kinase by combining molecular modeling, molecular dynamics (MD) simulations, and thermodynamic calculations. We predict the inhibitor conformation in the binding pocket of IRK and highlight that the charged residues in the histidine-arginine-aspartic acid (HRD) and aspartic acid-phenylalanine-glycine (DFG) motifs and the nonpolar residues in the binding pocket govern inhibitor interactions in the allosteric pocket of each kinase. We suggest that the conformational changes in the IGF1RK residues M1054 and M1079, movement of the ⍺C-helix, and the conformational stabilization of the DFG motif favor the selectivity of the inhibitor toward IGF1RK. Our thermodynamic calculations reveal that the observed selectivity can be rationalized through differences observed in the electrostatic interaction energy of the inhibitor in each inhibitor/kinase complex and the hydrogen bonding interactions of the inhibitor with the residue V1063 in IGF1RK that are not attained with the corresponding residue V1060 in IRK. Overall, our study provides a rationale for the molecular basis of recognition of this allosteric inhibitor by IGF1RK and IRK, which is potentially useful in developing novel inhibitors with improved affinity and selectivity.

Multilocular cystic nephroma in an adult: a diagnostic quandary

Multilocular cystic nephroma (MLCN) is an unusual, benign slow-growing renal cystic neoplasm which mimics other cystic renal lesions and has such clinical, radiological, and morphological features that causes diagnostic dilemma. MLCN lies in the spectrum of mixed epithelial and stromal tumor (MEST) family of kidney. According to World Health Organization (WHO 2016 classification), MEST encompasses spectrum of tumors ranging from predominantly cystic tumors, adult cystic nephroma (ACN) to tumors that are variably solid (MEST), thus creating diagnostic dilemma. Moreover, it has several benign and malignant differentials due to its several overlapping histomorphological features which when not cautiously dealt with may result in misdiagnosing it as malignant lesion. We hereby present a case of a woman in late twenties who presented with left flank swelling and pain since 6 months which was misdiagnosed as renal cell carcinoma on radiology which turned out to be ACN on histology and further verified on immunohistochemistry.

Collinsella aerofaciens linked with increased ethanol production and liver inflammation contribute to the pathophysiology of NAFLD

Non-alcoholic fatty liver disease (NAFLD) is an emerging global health problem and a potential risk factor for metabolic diseases. The bidirectional interactions between liver and gut made dysbiotic gut microbiome one of the key risk factors for NAFLD. In this study, we reported an increased abundance of Collinsella aerofaciens in the gut of obese and NASH patients living in India. We isolated C. aerofaciens from the fecal samples of biopsy-proven NASH patients and observed that their genome is enriched with carbohydrate metabolism, fatty acid biosynthesis, and pro-inflammatory functions and have the potency to increase ethanol level in blood. An animal study indicated that mice supplemented with C. aerofaciens had increased levels of circulatory ethanol, high levels of hepatic hydroxyproline, triglyceride, and inflammation in the liver. The present findings indicate that perturbation in the gut microbiome composition is a key risk factor for NAFLD.

Genomic and functional insights into antibiotic resistance genes floR and strA linked with the SXT element of Vibrio cholerae non-O1/non-O139

The emergence and spread of antibiotic-resistant bacterial pathogens are a critical public health concern across the globe. Mobile genetic elements (MGEs) play an important role in the horizontal acquisition of antimicrobial resistance genes (ARGs) in bacteria. In this study, we have decoded the whole genome sequences of multidrug-resistant Vibrio cholerae clinical isolates carrying the ARG-linked SXT, an integrative and conjugative element, in their large chromosomes. As in others, the SXT element has been found integrated into the 5'-end of the prfC gene (which encodes peptide chain release factor 3 involved in translational regulation) on the large chromosome of V. cholerae non-O1/non-O139 strains. Further, we demonstrate the functionality of SXT-linked floR and strAB genes, which confer resistance to chloramphenicol and streptomycin, respectively. The floR gene-encoded protein FloR belongs to the major facilitator superfamily efflux transporter containing 12 transmembrane domains (TMDs). Deletion analysis confirmed that even a single TMD of FloR is critical for the export function of chloramphenicol. The floR gene has two putative promoters, P1 and P2. Sequential deletions reveal that P2 is responsible for the expression of the floR. Deletion analysis of the N- and/or C-terminal coding regions of strA established their importance for conferring resistance against streptomycin. Interestingly, qPCR analysis of the floR and strA genes indicated that both of the genes are constitutively expressed in V. cholerae cells. Further, whole genome-based global phylogeography confirmed the presence of the integrative and conjugative element SXT in non-O1/non-O139 strains despite being non-multidrug resistant by lacking antimicrobial resistance (AMR) gene cassettes, which needs monitoring.

Development and Evaluation of an Eco-Friendly Hand Sanitizer Formulation Valorized from Fruit Peels

Hand sanitizer usage has proven to be a common and practical method for reducing the spread of infectious diseases which can be caused by many harmful pathogens. There is a need for alcohol-free hand sanitizers because most hand sanitizers on the market are alcohol-based, and regular use of them can damage the skin and can be hazardous. India is the world's largest producer of fruits and one of the major problems after fruit consumption is their peels, causing waste management problems and contributing to the formation of greenhouse gases leading to air pollution and adding to the problem of climate change. Valorization of such wastes into other value-added products and their incorporation into formulations of eco-friendly alcohol-free hand sanitizers would solve these issues, save the environment, benefit the society, and help in achieving the sustainable development goals. Thus, this research focuses on formulating an effective natural alcohol-free hand sanitizer that harnesses the antimicrobial properties of the various types of bioactive components found in fruit peels of pomegranate, sweet lime, and lemon. The peel extracts and the formulated sanitizer proved considerable antimicrobial activity against the pathogenic Escherichia coli and hand microflora. Molecular docking was also applied to examine ligand-protein interaction patterns and predict binding conformers and affinity of the sanitizer phytocompounds towards target proteins in COVID-19, influenza, and pneumonia viruses. The binding affinities and the protein-ligand interactions virtual studies revealed that the sanitizer phytocompounds bind with the amino acids in the target proteins' active sites via hydrogen bonding interactions. As a result, it is possible to formulate a natural, alcohol-free hand sanitizer from fruit peels that is effective against pathogenic germs and viruses using the basic structure of these potential findings.

From slides to insights: Harnessing deep learning for prognostic survival prediction in human colorectal cancer histology

Prognostic survival prediction in colorectal cancer (CRC) plays a crucial role in guiding treatment decisions and improving patient outcomes. In this research, we explore the application of deep learning techniques to predict survival outcomes based on histopathological images of human colorectal cancer. We present a retrospective multicenter study utilizing a dataset of 100,000 nonoverlapping image patches from hematoxylin & eosin-stained histological images of CRC and normal tissue. The dataset includes diverse tissue classes such as adipose, background, debris, lymphocytes, mucus, smooth muscle, normal colon mucosa, cancer-associated stroma, and colorectal adenocarcinoma epithelium. To perform survival prediction, we employ various deep learning architectures, including convolutional neural network, DenseNet201, InceptionResNetV2, VGG16, VGG19, and Xception. These architectures are trained on the dataset using a multicenter retrospective analysis approach. Extensive preprocessing steps are undertaken, including image normalization using Macenko's method and data augmentation techniques, to optimize model performance. The experimental findings reveal promising results, demonstrating the effectiveness of deep learning models in prognostic survival prediction. Our models achieve high accuracy, precision, recall, and validation metrics, showcasing their ability to capture relevant histological patterns associated with prognosis. Visualization techniques are employed to interpret the models' decision-making process, highlighting important features and regions contributing to survival predictions. The implications of this research are manifold. The accurate prediction of survival outcomes in CRC can aid in personalized medicine and clinical decision-making, facilitating tailored treatment plans for individual patients. The identification of important histological features and biomarkers provides valuable insights into disease mechanisms and may lead to the discovery of novel prognostic indicators. The transparency and explainability of the models enhance trust and acceptance, fostering their integration into clinical practice. Research demonstrates the potential of deep learning models for prognostic survival prediction in human colorectal cancer histology. The findings contribute to the understanding of disease progression and offer practical applications in personalized medicine. By harnessing the power of deep learning and histopathological analysis, we pave the way for improved patient care, clinical decision support, and advancements in prognostic prediction in CRC.

Attenuation of celecoxib cardiac toxicity using Poly(δ-decalactone) based nanoemulsion via oral route

Celecoxib (CLX), a poorly soluble anti-inflammatory drug, requires administration in higher concentrations to produce therapeutic effects, oftentimes resulting in cardiac toxicity. Therefore, in this study, we employed a nanoemulsion technology to improve the solubility of CLX using poly(δ-decalactone) (PDL) polymer as an oil and mPEG-b-PDL as a surfactant. The nanoemulsion (NE) was successfully prepared via the nanoprecipitation method. In vitro characterization was performed for size, drug release, and stability. In vivo studies were performed to establish anti-inflammatory activity, CLX induced cardiac toxicity, and pharmacokinetic profile of NE, post-oral administration. The globular size of less than 100 nm was obtained in NE with high CLX loading. The in vitro drug release studies suggested ∼90% of CLX release from NE within 96 h. A significant anti-inflammatory activity with lowered cardiac marker values was observed for CLX NE compared to a marketed drug formulation. The pharmacokinetic study revealed that the mean retention time of CLX was significantly increased with NE in contrast to the marketed formulation, suggesting the advantage of administering CLX in the form of NE owing to the higher solubility and sustained release pattern. The long-term storage stability study reveals that NE does not show significant changes in terms of size with only a slight decrement in CLX content was observed after 24 months. The obtained results indicate that CLX bioavailability has been considerably improved without being toxic to the heart with the aid of NE and advocate the use of PDL NE for developing oral formulations for poorly soluble drugs.

Relationship between Cardiovascular Risk Factors and Composite Cardiovascular Outcomes in Patients Hospitalized with Takotsubo Syndrome: A Nationwide Analysis

The association of traditional cardiovascular disease (CVD) risk factors with outcomes of Takotsubo syndrome (TTS) is not well-defined. This study examined how modifiable CVD risk factors affect composite cardiovascular outcomes in TTS hospitalizations. TTS admissions were identified using ICD-10 codes and compared for demographics and comorbidities using the 2019 National Inpatient Sample. A multivariable regression examined the association of traditional CVD risk variables with adverse composite cardiovascular outcomes in TTS, controlling for confounders including sociodemographic or hospital-level characteristics and other relevant comorbidities. A total of 16,055 (38.1%) of the 41,855 adult TTS admissions had composite cardiovascular outcomes (TACCO). The TACCO cohort was 81.5% white, 77.3% female, and 72 years old. This group had higher rates of diabetes and peripheral vascular disease (PVD). The results showed that a higher prevalence of diabetes with chronic complications (OR = 1.18) and complicated hypertension (HTN) (OR = 1.1) predicted TACCO, whereas tobacco use disorder (OR = 0.84), hyperlipidemia (OR = 0.76), and uncomplicated HTN (OR = 0.65) (p < 0.001) showed a paradoxical effect with TACCO. TACCO had fewer routine discharges (35.3% vs. 63.4%), longer stays (6 vs. 3 days), and higher median hospital costs (78,309 USD vs. 44,966 USD). This population-based study found that complicated HTN and DM with chronic complications are strongly associated with adverse cardiovascular outcomes in TTS hospitalizations. But still, some risk factors, such as hyperlipidemia and uncomplicated HTN, have counterintuitive effects that require further evaluation. To prevent cardiac events in TTS patients, traditional CVD risk factors must be addressed.

Lipid-Polymer Hybrid Nanosystems: A Rational Fusion for Advanced Therapeutic Delivery

Lipid nanoparticles (LNPs) are spherical vesicles composed of ionizable lipids that are neutral at physiological pH. Despite their benefits, unmodified LNP drug delivery systems have substantial drawbacks, including a lack of targeted selectivity, a short blood circulation period, and in vivo instability. lipid-polymer hybrid nanoparticles (LPHNPs) are the next generation of nanoparticles, having the combined benefits of polymeric nanoparticles and liposomes. LPHNPs are being prepared from both natural and synthetic polymers with various techniques, including one- or two-step methods, emulsification solvent evaporation (ESE) method, and the nanoprecipitation method. Varieties of LPHNPs, including monolithic hybrid nanoparticles, core-shell nanoparticles, hollow core-shell nanoparticles, biomimetic lipid-polymer hybrid nanoparticles, and polymer-caged liposomes, have been investigated for various drug delivery applications. However, core-shell nanoparticles having a polymeric core surrounded by a highly biocompatible lipid shell are the most commonly explored LPHNPs for the treatment of various diseases. In this review, we will shed light on the composition, methods of preparation, classification, surface functionalization, release mechanism, advantages and disadvantages, patents, and clinical trials of LPHNPs, with an emphasis on core-shell-structured LPHNPs.

Antimicrobial resistance heterogeneity among multidrug-resistant Gram-negative pathogens: Phenotypic, genotypic, and proteomic analysis

Microbes evolve rapidly by modifying their genomes through mutations or through the horizontal acquisition of mobile genetic elements (MGEs) linked with fitness traits such as antimicrobial resistance (AMR), virulence, and metabolic functions. We conducted a multicentric study in India and collected different clinical samples for decoding the genome sequences of bacterial pathogens associated with sepsis, urinary tract infections, and respiratory infections to understand the functional potency associated with AMR and its dynamics. Genomic analysis identified several acquired AMR genes (ARGs) that have a pathogen-specific signature. We observed that blaCTX-M-15, blaCMY-42, blaNDM-5, and aadA(2) were prevalent in Escherichia coli, and blaTEM-1B, blaOXA-232, blaNDM-1, rmtB, and rmtC were dominant in Klebsiella pneumoniae. In contrast, Pseudomonas aeruginosa and Acinetobacter baumannii harbored blaVEB, blaVIM-2, aph(3'), strA/B, blaOXA-23, aph(3') variants, and amrA, respectively. Regardless of the type of ARG, the MGEs linked with ARGs were also pathogen-specific. The sequence type of these pathogens was identified as high-risk international clones, with only a few lineages being predominant and region-specific. Whole-cell proteome analysis of extensively drug-resistant K. pneumoniae, A. baumannii, E. coli, and P. aeruginosa strains revealed differential abundances of resistance-associated proteins in the presence and absence of different classes of antibiotics. The pathogen-specific resistance signatures and differential abundance of AMR-associated proteins identified in this study should add value to AMR diagnostics and the choice of appropriate drug combinations for successful antimicrobial therapy.

Two non-active site residues W165 and L166 prominently influence the beta-lactam hydrolytic ability of OXA-23 beta-lactamase

Dissemination of class D OXA-type carbapenemases is one of the significant causes of beta-lactam resistance in Gram-negative bacteria. The amino acid residues present near the active site are involved in hydrolytic mechanism of class D carbapenemases, though it is not identified in OXA-23. Here, with the help of site-directed mutagenesis, we aimed to explicate the importance of the residues W165, L166 and V167 of the possible omega loop and residue D222 in the short β5-β6 loop on the activity of OXA-23. All the residues were substituted with alanine. The resultant proteins were assayed for the changes in activity in E. coli cells and purified for in vitro activity, and stability assessment. E. coli cells harboring OXA-23_W165A and OXA-23_L166A, individually, exhibited a significant decrease in resistance towards beta-lactam antibiotics as compared to OXA-23. Further, purified OXA-23_W165A and OXA-23_L166A imparted about >4-fold decrease in catalytic efficiency and displayed reduced thermal stability as compared to OXA-23. Bocillin-FL binding assay revealed that W165A substitution results in improper N-carboxylation of K82, leading to deacylation deficient OXA-23. Therefore, we infer that the residue W165 maintains the integrity of N-carboxylated lysine (K82) of OXA-23 and the residue L166 might be responsible for properly orientating the antibiotic molecules.

A Narrative Review of Signaling Pathway and Treatment Options for Diabetic Nephropathy

BACKGROUND

Diabetic nephropathy is a progressive kidney disease that frequently results in end-stage renal disorders and is characterized by proteinuria, albuminuria, decreased filtration, and renal fibrosis. Despite the fact that there are a number of therapeutic alternatives available, DN continues to be the main contributor to end-stage renal disease. Therefore, significant innovation is required to enhance outcomes in DN patients.

MATERIAL AND METHODS

Information was collected from online search engines like, Google Scholar, Web of Science, PubMed, Scopus, and Sci-Hub databases using keywords like diabetes, nephropathy, kidney disease, autophagy, etc. Result: Natural compounds have anti-inflammatory and antioxidant properties and impact various signaling pathways. They ameliorate kidney damage by decreasing oxidative stress, inflammatory process, and fibrosis and enhance the antioxidant system, most likely by activating and deactivating several signaling pathways. This review focuses on the role of metabolic memory and various signaling pathways involved in the pathogenesis of DN and therapeutic approaches available for the management of DN. Special attention is given to the various pathways modulated by the phytoconstituents.

Involvement of the non-active site Residues in the Catalytic Activity of NDM-4 Metallo beta-lactamase

The rise of New Delhi metallo beta-lactamase (NDM) producing bacteria imposes a significant threat to the treatment of bacterial infections due to their broad spectrum against beta-lactams. The activity of metallo beta-lactamases is affected by active site residues as well as residues near the active site. Therefore, we aimed to identify the amino acid residues around the active site of NDM-4 which influence its function. To achieve that, seven substitution mutations (S191A, D192A, S213A, K216A, S217A, D223A and D225A) of NDM-4 were generated through site-directed mutagenesis. Out of these, expression of NDM-4_D192A and NDM-4_S217A in Escherichia coli cells increased the beta-lactam susceptibility as compared to NDM-4. Further, proteins were purified to assess the effect of substitution mutations on zinc content, in vitro catalytic efficiency, and stability of NDM-4. The catalytic efficiency was reduced for these mutants (D192A and S217A) towards beta-lactam substrates, while the thermal stability remained insubstantial as compared to NDM-4. However, the purified NDM-4_D192A exhibited altered zinc content. In silico studies reveal that these changes might be the outcomes of alterations in hydrogen bonding networks and substrate interactions. Taken together, we infer that the D192 and the S217 residues play a substantial role in the activity of NDM-4.

Spatio-temporal investigation of physico-chemical water quality parameters based on comparative assessment of QUAL 2Kw and WASP model for the upper reaches of Yamuna River stretching from Paonta Sahib, Sirmaur district to Cullackpur, North Delhi districts of North India

An accurate investigation of bio-physical and chemical parameters as proxy of in situ water quality conditions in the Himalayan region is highly challenging owing to cumbersome, strenuous, and physically exhausting sampling exercises at high altitude locations. The upper stretches of Yamuna River in the Himachal Pradesh are typical examples of such sampling locations that have rarely been examined in the past studies. A widely accepted and recognized QUAL 2Kw model is applied for estimating the water quality parameters on the upper segment of the Yamuna River from Paonta Sahib to Cullackpur. These water quality indicators mainly included electric conductivity, pH, dissolved oxygen, temperature, carbonaceous biological oxygen demand (CBOD), inorganic suspended solids, total nitrogen, total phosphorus, and alkalinity, which were systematically investigated for predicting the spatio-temporal trends during the year 2018. A total of 12 distantly located river sites were identified for sample collection and data validation using QUAL 2Kw model. The present investigation attempts to reveal long-term degraded impact of untreated wastewater and biased agricultural practices on the water quality conditions over the upper stretches of Yamuna River. The QUAL 2Kw-derived values for selected variables were inter-compared with in situ values, and any deviation from measured values was ascertained based on meaningful statistical measures. The lower error of RMSE, MRE, and BIAS, corresponding to < 15%, ± 10%., ± 20%, and ~ 1 slope evidently indicated better matchup of values, wherein, higher slope correlation coefficient (R²) of ~ 90% indicated the robust performance of the QUAL 2Kw algorithm in accurately predicting the chosen variables. A comparative assessment of QUAL 2Kw and WASP has been performed to justify aptness of water quality model in scenarios of lean flow.

Region-specific genomic signatures of multidrug-resistant Helicobacter pylori isolated from East and South India

Helicobacter pylori is a ubiquitous bacterium and contributes significantly to the burden of chronic gastritis, peptic ulcers, and gastric cancer across the world. Adaptive phenotypes and virulence factors in H. pylori are heterogeneous and dynamic. However, limited information is available about the molecular nature of antimicrobial resistance phenotypes and virulence factors of H. pylori strains circulating in India. In the present study, we analyzed the whole genome sequences of 143 H. pylori strains, of which 32 are isolated from two different regions (eastern and southern) of India. Genomic repertoires of individual strains show distinct region-specific signatures. We observed lower resistance phenotypes and genotypes in the East Indian (Kolkata) H. pylori isolates against amoxicillin and furazolidone antibiotics, whereas higher resistance phenotypes to metronidazole and clarithromycin. Also, at molecular level, a greater number of AMR genes were observed in the east Indian H. pylori isolates as compared to the southern Indian isolates. From our findings, we suggest that metronidazole and clarithromycin antibiotics should be used judicially in the eastern India. However, no horizontally acquired antimicrobial resistance gene was observed in the current H. pylori strains. The comparative genome analysis shows that the number of genes involved in virulence, disease and resistance of H. pylori isolated from two different regions of India is significantly different. Single-nucleotide polymorphisms (SNPs) based phylogenetic analysis distinguished H. pylori strains into different clades according to their geographical locations. Conditionally beneficial functions including antibiotic resistance phenotypes that are linked with faster evolution rates in the Indian isolates.

Evaluation of air pollution tolerance index and anticipated performance index of selected roadside tree species in Ludhiana, India

Air quality has deteriorated in most big cities and becoming the fifth major cause of mortality in India. Among others, vehicle gaseous emission is a major contributor. Plants have different tolerance levels, which can be identified based on Air Pollution Tolerance Index (APTI). The objectives were to study the morphological and biochemical parameters for Air Pollution Tolerance Index (APTI) of selected roadside tree species (Acacia auriculiformis, Alstonia scholaris, Chukrasia tabularis, Cassia fistula, Cassia siamea, Dalbergia sissoo, Heterophragma adenophyllum, and Putranjiva roxburghii) at control (PAU campus) and polluted sites (roadside) during summer and winter seasons. The total chlorophyll content, ascorbic acid, leaf extract pH, leaf relative water content, total soluble sugar, phenols, and carotenoids ranged from 0.59 to 4.16 mg g^-1, 1.03 to 3.75 mg g^-1, 3.16 to 7.04, 46.01 to 71.65%, 10.78 to 23.83 mg g^-1, 0.51 to 1.35 mg ^-1, and 0.19 to 1.96 mg g^-1, respectively. The Air Pollution Tolerance Index of the selected trees ranged between7.65 and 11.19 and followed an order of Cassia fistula > Acacia auriculiformis > Dalbergia sissoo > Alstonia scholaris > Putranjiva roxburghii > Heterophragma adenophyllum > Cassia siamea > Chukrasia tabularis. The evaluation of Anticipated Performance Index (API) categorized the trees into poor (Dalbergia sissoo and Cassia siamea), moderate (Cassia fistula), and good (Acacia auriculiformis, Alstonia scholaris, Chukrasia tabularis, Heterophragma adenophyllum, and Putranjiva roxburghii) categories.

Carcinosarcoma of Gallbladder with Osteosarcomatous Differentiation - a Case Report with Review of Literature

A 44-year-old female presented with dull upper abdominal pain. Contrast-enhanced computed tomography (CECT) of the abdomen revealed a well-distended gallbladder with multiple foci of minimally enhancing, intraluminal, soft tissue lesion, and hyperdensity on non-contrast scan measuring 4.3 × 3.5 cm in the fundus with few calculi embedded in it. There was no evidence of extraluminal extension. The patient underwent extended cholecystectomy with liver wedge resection. Histologically, the tumor showed both carcinomatous and sarcomatous components, with prominent osteosarcomatous differentiation. We report this unusual case and present a review of all cases of carcinosarcoma of the gallbladder with sarcomatous differentiation. Despite curative resection, CSGB prognosis remains poor, and thus, the authors recommend to focus their efforts to improve the surgical outcomes.

The future of work post Covid-19: key perceived HR implications of hybrid workplaces in India

Purpose

Human history observed an arduous time fighting the novel infectious respiratory disease Covid-19 coronavirus, which started in Wuhan, China and spread rapidly across the globe in 2020. Economies and the countries including India around the world experienced dismay with nationwide lockdowns and the fear of the unknowing. The unforeseen circumstances enforced immediate transitions in the organizations' work environment through remote working, digital infrastructure, online collaborations and new ways of interaction. The pandemic altered the workplace trajectories in lasting ways as the employees settled into a new routine of working from home more quickly than imagined. Now, as India and many other countries slowly move beyond the crisis, there exists a need to realize the implications of the pandemic on the workplace and articulate the future of work. This article, therefore, investigates the key perceived benefits and the HR implications of the new and emerging concept of hybrid workplaces and presents an HRM framework for their successful adoption in India. The findings may prove crucial in framing new workplace norms and shaping them. Moreover, this research would provide practitioners, policymakers, business leaders and HR professionals insights about the need to review the existing workplaces and successfully roll out hybrid work models in accordance with HR strategies.

Design/methodology/approach

The methodology of Systematic Review of Literature (SLR) was adopted to study the key perceived benefits and the HR implications of hybrid workplaces.

Findings

The findings of the study would help business leaders, HR professionals, policymakers and researchers in developing HR policies and approaches for the adoption of the hybrid workplace as they chart the path toward the post-pandemic future.

Research limitations/implications

The study stresses the HR implications of the future of work as the hybrid workplace paradigm evolves. The approach is explorative and would require quantitative validation in different sectors and countries.

Originality/value

The study makes a direct link between the hybrid workplaces and the impetus for the transformation of HR strategies. It also examines the changing role of the human resources (HR) functions and professionals after the pandemic.

Predictors of acute pulmonary embolism-related hospitalizations – an artificial neural network analysis using a nationwide cohort in the United States

Background

Considering a paucity of large-scale data on predictors of pulmonary embolism (PE) and its higher association with complications and worse outcomes, we aimed to determine the predictors of PE in this United States population-based analysis using Artificial Neural Network (ANN) Model in a nationally representative cohort.

Methods

We identified PE-related hospitalizations using 2018's National Inpatient Sample database. The relevant predictive factors for ANN were selected for this cohort. Of all admissions (unweighted n=7,105,498, weighted n=35,527,481), PE cohort (weighted n=387805) consisted of 1.1% of all admissions in 2018. The 2018 cohort was randomly split into training data (unweighted n=4716132, 70.0%) which were used to calibrate ANN and testing data (unweighted n=2019290, 30%) which were used to assess the accurateness of the algorithm. We equated the rate of incorrect prediction between training and testing data and measured the Area under Receiver Operator Curve (AUC) to determine ANN's efficacy in predicting PE hospitalizations.

Results

Patients hospitalized with PE often consisted of older (mean age 62.5±17.1 years), female (51.3%), white (70.5%) patients, and patients from lower-income quartile (0–25% income quartile: 28.8%%), often admitted non-electively (93.7%) with higher rates of cardiovascular disease risk factors. PE admissions revealed significantly higher (6.5% vs. 1.9%, p&lt;0.001) in-hospital mortality, less frequent routine discharges (51.4% vs. 68.1%) and more frequent other facility transfers and requirement of home health care. Normalized Predictors of PE admissions are displayed in Fig. 1. Our ANN model had AUC 0.873 which correlates with an excellent prediction model. Our data demonstrated low levels (0.8%) error in both testing and training models.

Conclusion

Our ANN model showed high performance to predict risk factors for PE admissions in the US population. It will enable clinicians to screen patients at high-risk for PE admissions, curtail complication rate, improve survival and lower the healthcare cost.

Funding Acknowledgement

Type of funding sources: None.

Morvan's syndrome: An unusual presentation of a solid pseudopapillary pancreatic tumor

Morvan's syndrome is a rare anti-contactin-associated protein-like 2 (CASPR2) antibody-mediated autoimmune disorder. The clinical features of this syndrome include muscular twitching, insomnia, dysautonomia, peripheral nerve hyperexcitability, and fluctuating delirium. An underlying tumor is commonly found among Morvan's syndrome cases, with thymoma being the most frequent association. We describe an unusual case of a 39-year-old female with excruciating bilateral leg pain, insomnia, hyperhidrosis, peripheral nerve hyperexcitability, serum anti-CASPR2 antibody positivity, and a solid pseudopapillary tumor of the pancreas on histopathology. Furthermore, the patient's symptoms improved after receiving intravenous immunoglobulin (0.4 g/kg per day for 5 days). To the best of our knowledge, this is the first case of Morvan syndrome associated with a solid pseudopapillary pancreatic tumor to be reported in the literature to date. Our case adds to the spectrum of malignancies that are associated with Morvan's syndrome. The recognition of this rare syndrome and its various associations are important for the neurologist, as it is a potentially treatable condition.

Antibiotic Potentiators Against Multidrug-Resistant Bacteria: Discovery, Development, and Clinical Relevance

Antimicrobial resistance in clinically important microbes has emerged as an unmet challenge in global health. Extensively drug-resistant bacterial pathogens have cropped up lately defying the action of even the last resort of antibiotics. This has led to a huge burden in the health sectors and increased morbidity and mortality rate across the world. The dwindling antibiotic discovery pipeline and rampant usage of antibiotics has set the alarming bells necessitating immediate actions to combat this looming threat. Various alternatives to discovery of new antibiotics are gaining attention such as reversing the antibiotic resistance and hence reviving the arsenal of antibiotics in hand. Antibiotic resistance reversal is mainly targeted against the antibiotic resistance mechanisms, which potentiates the effective action of the antibiotic. Such compounds are referred to as resistance breakers or antibiotic adjuvants/potentiators that work in conjunction with antibiotics. Many studies have been conducted for the identification of compounds, which decrease the permeability barrier, expression of efflux pumps and the resistance encoding enzymes. Compounds targeting the stability, inheritance and dissemination of the mobile genetic elements linked with the resistance genes are also potential candidates to curb antibiotic resistance. In pursuit of such compounds various natural sources and synthetic compounds have been harnessed. The activities of a considerable number of compounds seem promising and are currently at various phases of clinical trials. This review recapitulates all the studies pertaining to the use of antibiotic potentiators for the reversal of antibiotic resistance and what the future beholds for their usage in clinical settings.

Pseudomonas aeruginosa isolate PM1 effectively controls virus infection and promotes growth in plants

A bacterial isolate PM1 obtained from the rhizosphere of healthy plants was identified as Pseudomonas aeruginosa by biochemical characteristics and 16S rRNA gene sequence (GenBank ID OL321133.1). It induced resistance in Nicotiana tabacum cv. Xanthi-nc and Cyamopsis tetragonoloba, against Tobacco mosaic virus (TMV) and Sunn-hemp rosette virus (SRV), respectively. Foliar treatment with isolate PM1 curbed TMV accumulation in susceptible N. tabacum cv. White Burley. PM1 was more effective as a foliar than a root/soil drench treatment, evident through a comparative decrease in ELISA values, and reduced viral RNA accumulation. Foliar and soil drench treatment with PM1 resulted in a disease index of 48 and 86 per cent, and a control rate of 48.9 and 8.5 per cent, respectively. PM1 exhibited phosphate solubilization, produced siderophores, auxins, HCN, and ammonia, all important plant growth-promoting traits. Foliar treatment with PM1 enhanced growth in tobacco, while its volatiles significantly promoted seedling growth in C. tetragonoloba. Of the several metabolites produced by the isolate, many are known contributors to induction of systemic resistance, antibiosis, and growth promotion in plants. Soluble metabolites of PM1 were less effective in inducing antiviral resistance in N. tabacum cv. Xanthi-nc in comparison with its broth culture. PM1 and its metabolites were antagonistic to Gram-positive Bacillus spizizenii and Staphylococcus aureus, and fungi Fusarium oxysporum, Aspergillus niger, and Rhizopus stolonifer. Its volatiles were inhibitory to F. oxysporum and R. stolonifer. Thus, PM1 exhibited considerable potential for further evaluation in plant virus control and production of diverse metabolites of use in agriculture and medicine.

In silico identification and in vitro antiviral validation of potential inhibitors against Chikungunya virus

The Chikungunya virus (CHIKV) has become endemic in the Africa, Asia and Indian subcontinent, with its continuous re-emergence causing a significant public health crisis. The unavailability of specific antivirals and vaccines against the virus has highlighted an urgent need for novel therapeutics. In the present study, we have identified small molecule inhibitors targeting the envelope proteins of the CHIKV to interfere with the fusion process, eventually inhibiting the cell entry of the virus particles. We employed high throughput computational screening of large datasets against two different binding sites in the E1-E2 dimer to identify potential candidate inhibitors. Among them, four high affinity inhibitors were selected to confirm their anti-CHIKV activity in the in vitro assay. Quercetin derivatives, Taxifolin and Rutin, binds to the E1-E2 dimer at different sites and display inhibition of CHIKV infection with EC₅₀ values 3.6 μM and 87.67 μM, respectively. Another potential inhibitor with ID ChemDiv 8015-3006 binds at both the target sites and shows anti-CHIKV activity at EC₅₀ = 41 μM. The results show dose-dependent inhibitory effects of Taxifolin, Rutin and ChemDiv 8015-3006 against the CHIKV with minimal cytotoxicity. In addition, molecular dynamics studies revealed the structural stability of these inhibitors at their respective binding sites in the E1-E2 protein. In conclusion, our study reports Taxifolin, Rutin and ChemDiv 8015-3006 as potential inhibitors of the CHIKV entry. Also, this study suggests a few potential candidate inhibitors which could serve as a template to design envelope protein specific CHIKV entry inhibitors.

Deciphering the role of residues in the loops nearing the active site of OXA-58 in imparting beta-lactamase activity

The existence of OXA-58 carbapenemase alone or in combination with other beta-lactam resistance factors poses significant beta-lactam resistance. The exact mechanism of action of OXA type beta-lactamases is debatable due to the involvement of multiple residues within or outside the active site. In the present work, we have elucidated the relative role of residues present in the putative omega (W169, L170, K171) and β6-β7 (A226 and D228) loops on the activity of OXA-58 by substituting into alanine (and aspartate for A226) through site-directed mutagenesis. E. coli cells harbouring OXA-58, substituted at the putative omega loop, manifest a significant decrease in the beta-lactam resistance profile than that of the cells expressing OXA-58. Further, a reduction in the catalytic efficiency is observed for the purified variants of OXA-58 carrying individual substitutions in the putative omega loop than that of OXA-58. However, the addition of NaHCO₃ (for carbamylation of K86) increases catalytic efficiency of the individual protein as revealed by nitrocefin hydrolysis assay and steady state kinetics. Moreover, W169A and K171A substitutions show significant effects on the thermal stability of OXA-58. Therefore, we conclude that the putative omega loop residues W169, L170 and K171, individually, have significant role in the activity and stability of OXA-58, mostly by stabilising carbamylated lysine of active site.

Abstract 69: Predictors Of Cardiac Arrest-related Hospitalizations In Young (18-44 Years) Females - An Artificial Neural Network Analysis Using A Nationwide Cohort

Background: Considering the limited availability of data on Cardiac Arrest (CA) in young patients and especially females, we aimed to determine the predictors of CA in this population using Artificial Neural Network (ANN) Model in a national cohort from the United States.

Methods: We identified CA-related hospitalizations among young females (18-44 years) using 2018’s National Inpatient Sample database. ANN’s predictive factors were selected for this cohort. Young females with CA (n=10810, 0.2% of all 2018 young female admissions) were randomly split into training data (n=7567, 70%) which were used to calibrate ANN and testing data (n=3243, 30%) which were used to evaluate the accuracy of the algorithm. We compared the frequency of incorrect prediction between training and testing data and measured the Area under Receiver Operator Curve (AUC) to determine ANN’s efficacy in predicting CA.

Results: Young females with CA often consisted of older (median age 36 vs 30 years), blacks (25.3% vs 18%), and patients from lower-income quartile (0-25% income quartile:36.4% vs 29.9%) with higher rates of modifiable cardiovascular disease risk factors vs. females admitted without CA (p<0.001). Females with CA expectedly had significantly high (48.4%) in-hospital mortality. Normalized Predictors are displayed in Table 1. Our ANN model had AUC 0.902 (Fig 1) which correlates with an excellent prediction model. Our data showed 0.2% error in both testing and training models.

Conclusion: Our ANN model achieved high performance to predict risk factors for CA admissions in young females. It will enable clinicians to screen high-risk young female hospitalized patients and improve survival in them.

Abstract 158: Burden And Predictors Of Mortality And Major Adverse Cardiovascular Outcomes In Heart Failure Preserved Ejection Fraction Patients Admitted With Acute Respiratory Distress Syndrome (ARDS)

Background: Relation between Acute Respiratory Distress Syndrome (ARDS) and heart failure with preserved ejection fraction (HFpEF) are understudied and the data on these two concomitantly is lacking in the literature. Therefore, we sought to assess the burden and predictors of major adverse cardiovascular and cerebrovascular events (MACCE) and all-cause mortality in ARDS patients with HFpEF.

Methods: The National Inpatient Sample (NIS) database was used to identify patients with HFpEF (after excluding patients with heart failure reduced ejection fraction) who required inpatient hospitalization for ARDS. Administrative ICD10 codes were used to identify the population of interest. Multivariate regression analysis was performed to assess the predictors of all-cause mortality and major adverse cardiovascular outcomes in the selected cohort.

Results: Of 28,731,562 hospital admissions, 3,010 (0.14%) patients were admitted with ARDS and had HFpEF. Of those patients, 1,095 (36.4%) had all-cause mortality, and 1,415 (47.0%) had MACCE. In multivariate regression analysis, older age (OR 3.60, CI 1.40-9.28), 26-50 th quartile income (OR 2.10, CI 1.13-3.91), urban hospital admissions (OR 2.19, CI 1.20-4.01) as well as comorbidities such as coagulopathy (OR 1.77, CI 1.09-2.88), fluid and electrolyte imbalance (OR 1.65, CI 1.05-2.60), prior CABG (OR 2.99, CI 1.19-7.47), need for mechanical ventilation (OR 2.18, CI 1.12-4.23) were significant predictors of all-cause mortality. In our analysis, chronic pulmonary disease, valvular heart disease, hypertension, smoking, obesity were not significant predictors. The result of our analysis is reported in Table 1.

Conclusion: These results suggest HFpEF remains important comorbidity in ARDS patients. Here, we identified predictors of poor outcomes in this patient population which may help physicians to identify the high-risk patients and decrease mortality.

In silico identification of small molecule protein-protein interaction inhibitors: targeting hotspot regions at the interface of MXRA8 and CHIKV envelope protein

Chikungunya virus (CHIKV) is an arthritogenic arbovirus responsible for re-emerging epidemics of Chikungunya fever around the world for centuries. Chikungunya has become endemic in Africa, Southeast Asia, the Indian subcontinent, and subtropical regions of the Americas. The unavailability of antiviral therapy or vaccine against the CHIKV and its continuous re-emergence demands an urgent need to develop potential candidate therapeutics. CHIKV entry into the host cell is mediated by its envelope proteins engaging the cellular receptor MXRA8 to invade the susceptible cells. We report here two essential target binding sites at the CHIKV E1-E2 proteins by identifying hotspot regions at the E1-E2-MXRA8 binding interface. Further, we employed high throughput computational screening to identify potential small molecule protein-protein interaction (PPI) modulators which could effectively bind at the identified target sites. Molecular dynamics simulations and binding free energy calculations confirmed the stability of three compounds, viz., ZINC299817498, ZINC584908978, and LAS52155651, at both the predicted interface binding sites. The polar and charged residues at the interface were responsible for energetically holding the ligands at the binding sites. Altogether, our findings suggest that the predicted target binding sites at the E1-E2 dimer could be essential to block the receptor interaction as well as the fusion process of the CHIKV particles. Thus, we identified a few small molecule PPI inhibitors with great potential to block the E1-E2-MXRA8 interaction and act as promising templates to design anti-CHIKV drugs.Communicated by Ramaswamy H. Sarma.

Analysis of colistin resistance in carbapenem-resistant Enterobacterales and XDR Klebsiella pneumoniae

Introduction:

Increasing occurrence of infections caused by multidrug-resistant Gram-negative bacteria resulted in colistin being the last agent for treatment. Apart from plasmid-mediated mcr genes, mutations involving several genes like mgrB, phoP/phoQ, pmrA, pmrB, pmrC, and crrABC genes, are leading causes of colistin resistance. Four colistin susceptibility testing methods were compared against broth microdilution (BMD) and determined the presence of the mcr1-5 gene.

Methodology:

A total of 100 carbapenem-resistant Enterobacterales isolates were tested for colistin susceptibility by commercial broth microdilution (cBMD), E-test, VITEK-2, and rapid polymyxin NP assay (RPNP) and compared with BMD. The presence of the mcr1-5 gene was determined by modified RPNP and PCR. Two non-mcr colistin-resistant XDR isolates were subjected to whole-genome sequencing using Illumina MiSeq sequencing platform.

Results:

Among 100 carbapenem-resistant Enterobacterales isolates, 15% were resistant to colistin. Essential agreement, categorical agreement, major error, and very major error for cBMD/E-test/VITEK-2/RPNP were 96%/73%/82%/NA; 99%/86%/88%/91%, 1.2%/9.4%/11.8%/8.2% and 0%/40%/13.3%/13.3%, respectively. Only one Klebsiella pneumoniae isolate harbored the mcr-1 gene, observed by both methods. Whole-genome sequencing of two non-mcr XDR Klebsiella pneumoniae showed multiple mutations in 10 genes responsible for lipopolysaccharide biosynthesis.

Conclusions:

The performance of cBMD was excellent, whereas the E-test was unacceptable. VITEK-2 and RPNP performed better but remained unreliable due to high error rates. Multiple mutations in the target proteins involving lipopolysaccharide formation, modification, and regulation were seen, resulting in colistin resistance.

Comparative insight into the roles of the non active-site residues E169 and N173 in imparting the beta-lactamase activity of CTX-M-15

CTX-M-15 is a major extended-spectrum beta-lactamase disseminated throughout the globe. The roles of amino acids present in the active-site are widely studied though little is known about the role of the amino acids lying at the close proximity of the CTX-M-15 active-site. Here, by using site-directed mutagenesis we attempted to decipher the role of individual amino acids lying outside the active-site in imparting the beta-lactamase activity of CTX-M-15. Based on the earlier evidence, three amino acid residues namely, Glu169, Asp173 and Arg277 were substituted with alanine. The antibiotic susceptibility of E. coli cells harboring E169A and N173A substituted CTX-M-15 were enhanced by ∼ >32 fold for penicillins and ∼ 4-32 fold for cephalosporins, in comparison to CTX-M-15. However, cells carrying CTX-M-15_R277A did not show a significant difference in antibiotic susceptibility as compared to the wild-type. Further, the catalytic efficiency of the purified CTX-M-15_E169A and CTX-M-15_N173A were compromised when compared with the efficient beta-lactam hydrolysis of purified CTX-M-15. Moreover, the thermal stability of the mutated proteins CTX-M-15_E169A and CTX-M-15_N173A were reduced as compared to the wild type CTX-M-15. Therefore, we conclude that E169 and N173 are crucial non-active-site amino acids that are able to govern the CTX-M-15 activity.

A comparison of induced antiviral resistance by the phytoprotein CAP-34 and isolate P1f of the rhizobacterium Pseudomonas putida

CAP-34 is a previously reported phytoprotein isolated from Clerodendrum aculeatum (syn. Volkameria aculeata), inducing systemic antiviral resistance against plant virus infection in susceptible plants. This paper compares the resistance inducing efficacy of CAP-34 and a rhizobacterial isolate P1f on tomato (systemic) and tobacco Xanthi-nc (hypersensitive), against tobacco mosaic virus (TMV). The PGPR isolate was identified as an isolate of Pseudomonas putida through molecular and biochemical characterization, and it exhibited PGPR traits such as production of auxin and siderophore. GC-MS examination of the volatiles produced by P1f included several that are implicated in antimicrobial activity, growth promotion and induced systemic resistance. Foliar treatment of tobacco plants with P1f and CAP-34 led to an induced antiviral state in hypersensitive tobacco that persisted for 5 and 3 days, post-treatment, respectively, with a percent reduction in lesion number greater than 90. A higher accumulation of hydrogen peroxide and production of peroxidase enzyme was recorded in P1f-treated leaves, in comparison to those with CAP-34 treatment. The disease incidence in tomato plants treated with CAP-34 and P1f was 30 and 60 percent, respectively, 28dpi. A significant increase was noted in growth parameters such as number of branches and flowers in CAP-34 treated plants, while a significant enhancement in plant height and dry shoot and root weight was observed in P1f-treated set, compared to the control set. ELISA values for the presence of TMV were significantly lower in the infected tomato plants in the treated sets, as compared to the control set, with CAP-34 treatment exhibiting better results as against the P1f-treated set. In the resistant plants from either set, no viral RNA or viral coat protein was detected through RT-PCR and serology. These results suggest that CAP-34 affords more pronounced protection against virus infection compared to the rhizobacterial isolate P1f.

Antimicrobial resistance and virulence in Helicobacter pylori: Genomic insights

Microbes evolve rapidly by modifying their genome through mutations or acquisition of genetic elements. Antimicrobial resistance in Helicobacter pylori is increasingly prevalent in India. However, limited information is available about the genome of resistant H. pylori isolated from India. Our pan- and core-genome based analyses of 54 Indian H. pylori strains revealed plasticity of its genome. H. pylori is highly heterogenous both in terms of the genomic content and DNA sequence homology of ARGs and virulence factors. We observed that the H. pylori strains are clustered according to their geographical locations. The presence of point mutations in the ARGs and absence of acquired genetic elements linked with ARGs suggest target modifications are the primary mechanism of its antibiotic resistance. The findings of the present study would help in better understanding the emergence of drug-resistant H. pylori and controlling gastric disorders by advancing clinical guidance on selected treatment regimens.

Insilico study on the effect of SARS-CoV-2 RBD hotspot mutants' interaction with ACE2 to understand the binding affinity and stability

The fall of 2020 brought several new variants of SARS-CoV-2 circulating across the globe, and the steadily increasing COVID-19 cases are responsible for the emergence of these variants. All the SARS-CoV-2 variants reported to date have multiple mutations in the spike (S) protein, specifically in the receptor-binding domain (RBD). Here, we employed an integrated computational approach involving structure and sequence based predictions to study the effect of naturally occurring variations in the S-RBD on its stability and ACE2 binding affinity. The hotspot stabilizing residue mutations N501I, N501Y, Q493L, Q493H and K417R, strengthen the RBD-ACE2 complex by modulating the interaction statistics at the interface. Thus, we report here some critical mutations that could increase the binding affinity of the SARS-CoV-2 RBD with ACE2, increasing the viral infectivity and pathogenicity. Understanding the effect of these mutations will help in developing potential vaccines and therapeutics.

A comparative study of human betacoronavirus spike proteins: structure, function and therapeutics

Coronaviruses are the paradigm of emerging 21st century zoonotic viruses, triggering numerous outbreaks and a severe global health crisis. The current COVID-19 pandemic caused by SARS-CoV-2 has affected more than 51 million people across the globe as of 12 November 2020. The crown-like spikes on the surface of the virion are the unique structural feature of viruses in the family Coronaviridae. The spike (S) protein adopts distinct conformations while mediating entry of the virus into the host. This multifunctional protein mediates the entry process by recognizing its receptor on the host cell, followed by the fusion of the viral membrane with the host cell membrane. This review article focuses on the structural and functional comparison of S proteins of the human betacoronaviruses, severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we review the current state of knowledge about receptor recognition, the membrane fusion mechanism, structural epitopes, and glycosylation sites of the S proteins of these viruses. We further discuss various vaccines and other therapeutics such as monoclonal antibodies, peptides, and small molecules based on the S protein of these three viruses.

Designing novel inhibitors against cyclopropane mycolic acid synthase 3 (PcaA): targeting dormant state of Mycobacterium tuberculosis

Mycobacterium tuberculosis can sustain inside the host in dormant (non-replicating) state for years. It suppresses the host immune system by residing in the host alveolar macrophage, resulting in the development of latent tuberculosis. Despite many antibiotics available for the treatment of tuberculosis, the major hurdle in complete elimination is the ability of the bacilli to undergo dormancy and develop resistance against the existing drugs. Cyclopropanation of mycolic acids present in the cell wall of mycobacteria is required for its persistence and virulence. Cyclopropane synthases such as PcaA, CmaA1 and CmaA2, introduce site-specific modifications in mycolic acids. PcaA expression levels are high during dormancy and the gene mutants fails to persist, showing reduced survival in host macrophage. Hence, PcaA appears as a potential target to develop inhibitors against the dormant bacilli. In this study, we have identified compounds with maximum binding affinity against PcaA by in-silico virtual screening of anti-tuberculosis compounds and their structural analogues. In-silico docking followed molecular dynamic simulations and free energy calculations of the compounds with highest docking score in their respective libraries. This study reports novel inhibitors that can act as better anti-tuberculosis compounds targeting PcaA.Communicated by Ramaswamy H. Sarma.

Estimation of a stronger heparin binding locus in fibronectin domain III14using thermodynamics and molecular dynamics

The HEP II (Heparin-binding site II) region of fibronectin (FN) containing domain III¹⁴ plays a crucial role in cell adhesion and migration through heparin-binding on the cell surface. There are two such fibronectin heparin interacting peptide (FHIP I and FHIP II) sequences present in HEP II. However, the molecular principles by which these sites orchestrate heparin-binding processes are poorly understood. Such knowledge would have great implications in the therapeutic targeting of FN. With this aim, we have explored the binding studies of FHIP I and FHIP II with heparin using various biophysical methods. A fluorescence melting study specifically revealed the preference of heparin for domain III in FN, indicating the key contribution of FHIP I and FHIP II in heparin binding. In isothermal titration calorimetry (ITC), the higher binding affinity observed for FHIP II (∼10⁷ mol⁻¹) compared to FHIP I (∼10⁶ mol⁻¹) is expected due to the presence of a superior cluster of Arg and Lys residues in FHIP II, which can facilitate specific H-bonding interactions with heparin. Based on heat capacity changes, the key role of H-bonding, electrostatic and hydrophobic interactions was demonstrated in binding. Finally, the molecular docking and MD simulation results reinforced that the interaction of heparin (dodecasaccharide) is stronger and stable with the FHIP II peptide. The results described here suggest that these peptides provide all the structural and thermodynamic elements necessary for heparin-binding of HEP II of FN. Subsequently, it can be concluded that FHIP II could be a better location for therapeutic intervention in cell adhesion activity by FN.

Binding Thermodynamics of FHIP I and FHIP II with heparin.

Validation of Bifurcohaptor spp. (Monogenoidea: Dactylogyridae) reported from India using molecular methods with inclusion of insilico study: A brief report on its host-specificity

A total of 17 species of the genus Bifurcohaptor Jain, 1958 have been reported from two fish families namely Bagridae Bleeker, 1858 (Mystus vittatus (Bloch, 1794), M. tengara (Hamilton, 1822), M. keletius (Valenciennes, 1840), Hemibagrus nemurus (Valenciennes, 1840), Rita rita (Hamilton, 1822) and Sperata seenghala (Sykes, 1839)) and Sisoridae Bleeker, 1858 (Bagarius bagarius (Hamilton, 1822)). Out of these, only two species viz. B. indicus and B. giganticus are found valid in India, parasitizing gills of Mystus spp. and Bagarius sp. Taxonomic studies suggest, present specimen of B. indicus and B. giganticus, both are morphologically close to species described by Jain (1958), except morphometric variations and posses 7 pairs of marginal hooks instead of 6 pairs. Present manuscript delves with the characterization of B. indicus and B. giganticus reported from India, using molecular techniques. Partial mt COI nucleotide sequence based insilico protein analysis and partial 28S and ITS-1 rDNA based phylogenetic analysis, estimated by Neighbour-joining (NJ) and Minimum Evolution (ME) methods revealed that the species of the genus Bifurcohaptor are genetically distinct and valid. The grouping of Bifurcohaptor spp. with other representatives of family Dactylogyridae supports morphology based placement into family Dactylogyridae. Present and previous host-parasite information suggests both Bifurcohaptor spp. are species specialist however, the genus Bifurcohaptor is generalist at generic level.

Bihari Identity: An Uncharted Question

Sources of multidisciplinary social sciences were consulted for understanding the Bihari identity narrative. Bihar’s glorious history and landmark events of 100 years (1912–2012), were briefly examined. Observations and sparse empirical findings were used for presenting the Bihari identity discourse. Seemingly, the identities ‘fighter’ and ‘revolutionary’ resulted from the land’s rebellious background while unfair treatment during colonial and post-colonial rules conferred the identity ‘poor and backward’ to the state. Difficult conditions kept Bihar’s population on move and Biharis became identified as ‘migrants’. Lalu–Rabri’s regime (1990–2005) thoroughly tarnished the state’s image while feudal mentality, caste differentiation, political ambition and collective power of the oppressed constituted the identities ‘criminals’ and ‘violent’. Empirical evidence indicates that the struggling middle class wanted power was competitive and untrusting. Nevertheless, Biharis were sensitive towards others’ feelings, cared for relationships, were intelligent, hardworking and patient. An insider finds elements of simplicity in Bihari people’s attire and etiquette but also perceive them to be undisciplined, socially irresponsible and tolerant towards corruption. However, Bihari identity was in transition; backward caste was in power, social justice and development were utilized as power managing strategies and urban Biharis were opting for capitalist culture. Although Bihari identity remains tied to caste and subregions, it seems to be a subset of Indian identity.