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Fulltext Structure-Based Screening of Non-β-Lactam Inhibitors against Class D β-Lactamases: An Approach of Docking and Molecular Dynamics

Gupta D, Singh A, Somvanshi P, Singh A, Khan AU

ACS Omega, 2020 Apr 28;5(16):9356-9365.
PMID: 32363287 DOI: 10.1021/acsomega.0c00356

The manifestation of class D β-lactamases in the community raises significant concern as they can hydrolyze carbapenem antibiotics. Hence, it is exceptionally alluring to design novel inhibitors. Structure-based virtual screening using docking programs and molecular dynamics simulations was employed to identify two novel non-β-lactam compounds that possess the ability to block different OXA variants. Furthermore, the presence of a nonpolar aliphatic amino acid, valine, near the active site serine, was identified in all OXA variants that can be accounted to block the catalytic activity of OXA enzymes.
"Airplane ear"-A neglected yet preventable problem

Bhattacharya S, Singh A, Marzo RR

AIMS Public Health, 2019;6(3):320-325.
PMID: 31637280 DOI: 10.3934/publichealth.2019.3.320
Delivering emoji/icon-based universal health education messages through smartphones

Bhattacharya S, Singh A, Marzo RR

AIMS Public Health, 2019;6(3):242-247.
PMID: 31637274 DOI: 10.3934/publichealth.2019.3.242
Seasonal expression and distribution of kisspeptin1 (kiss1) in the ovary and testis of freshwater catfish, Clarias batrachus: A putative role in steroidogenesis

Singh A, Lal B, Parhar IS, Millar RP

Acta Histochem, 2021 Sep;123(6):151766.
PMID: 34384940 DOI: 10.1016/j.acthis.2021.151766

The central role of kisspeptin (kiss) in mammalian reproduction is well established; however, its intra-gonadal role is poorly addressed. Moreover, studies investigating intra-gonadal role of kiss in fish reproduction are scanty, contradictory and inconclusive. The expression of kiss1 mRNA has been detected in the fish brain, and functionally attributed to the regulation of reproduction, feeding and behavior. The kiss1 mRNA has also been demonstrated in tissues other than the brain in some studies, but its cellular distribution and role at the tissue level have not been adequately addressed in fish. Therefore, an attempt was made in the present study to localize kiss1 in gonadal cells of the freshwater catfish, Clarias batrachus. This study reports the presence of kiss1 in the theca cells and granulosa cells of the ovarian oocytes and interstitial cells in the testis of the catfish. The role of kiss1 in the ovary and testis of the catfish was also investigated using kiss1 receptor (kiss1r) antagonist (p234). The p234 treatment decreased the production of 17β-estradiol in ovary and testosterone in the testis by lowering the activities of 3β-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase under both, in vivo as well as in vitro conditions. The p234 treatment also arrested the progression of oogenesis, as evident from the low number of advancing/advanced oocytes in the treated ovary in comparison to the control ovary. It also reduced the area and perimeter of the seminiferous tubules in the treated catfish testis. Thus, our findings suggest that kiss is involved in the regulation of gonadal steroidogenesis, independent of known endocrine/ autocrine/ paracine regulators, and thereby it accelerates gametogenic processes in the freshwater catfish.
Avian Haemosporidian (Plasmodium and Haemoproteus) Status in Two Bird Groups (Old-World Flycatchers and Thrushes) of India and Their Phylogenetic Relationships with Other Lineages of the World

Vipin, Singh A, Sharma V, Tripathi NK, Dixit R, Singh B, et al.

Acta Parasitol, 2022 Dec;67(4):1756-1766.
PMID: 36306015 DOI: 10.1007/s11686-022-00626-1

PURPOSE: Avian haemosporidian may affect the host from body damage to the extinction of a population. Knowledge of their status may help in future avifauna conservation plans. Hence, their status in two bird groups of India and their phylogenetic relationships with other known lineages of the world were examined.
METHODS: Cytochrome b gene sequences (479 bp) generated from India and available at MalAvi database were used to study the avian haemosporidian prevalence and phylogenetic analysis of lineages at local and world levels.
RESULTS: One common (COLL2) and only once in the study (CYOPOL01, CHD01, CYORUB01, EUMTHA01, GEOCIT01) haemosporidian lineages were discovered. 5.88% prevalence of haemosporidian infection was found in 102 samples belonging to 6 host species. Haemoproteus prevalence was 4.90% across five host species (Phylloscopus trochiloides, Cyornis poliogenys, C. hainanus dialilaemus, C. rubeculoides, Eumiyas thalassinus) and Plasmodium prevalence was 0.98% in Geokichla citrina. Spatial phylogeny at the global level showed that COLL2 lineage, found in C. poliogenys in India, was genetically identical to H. pallidus lineages (COLL2) in parts of Africa, Europe, North America, Malaysia, and the Philippines. The Plasmodium lineage (GEOCIT01) was related to PADOM16 in Egypt, but the sequences were only 93.89% alike.
CONCLUSIONS: Four new lineages of Haemoproteus and one of Plasmodium were reported. COLL2 similarity with other H. pallidus lineages may suggest their hosts as possible infection sources.
Uterine bleeding with an IUD requiring emergency hysterectomy

Glew S, Singh A

Adv Contracept, 1989 Mar;5(1):51-3.
PMID: 2782134

A case is described of profuse uterine bleeding with a dislodged Multiload Cu 250 intrauterine device (IUD). Multiple blood transfusions were necessary, and ultimately, an emergency hysterectomy was performed.
Fulltext The complexity of stromal changes in desmoplastic ameloblastoma

Ramesh V, Singh S, Bailwad S, Kiran K, Agarwal R, Singh A

Ann Med Health Sci Res, 2014 Mar;4(Suppl 1):S14-7.
PMID: 25031898 DOI: 10.4103/2141-9248.131694

Ameloblastoma is usually considered a homogenous neoplasm and is thought of as the most primitive of all odontogenic neoplasms. However, detailed investigations have proven clinicopathological diversity in a significant number of cases, thus mounting the evidence in favor of considering ameloblastoma as a mysterious lesion. The purpose of this article is to report a unique case of desmoplastic ameloblastoma and to throw light on the atypical changes noticed in the stromal component. The findings of this case have served to add interesting parameters to the study of stromal changes associated with this perplexing odontogenic tumor.
Synthesis of Pectin and Eggshell Biowaste-Mediated Nano-hydroxyapatite (nHAp), Their Physicochemical Characterizations, and Use as Antibacterial Material

Thakur P, Arivarasan VK, Kumar G, Pant G, Kumar R, Pandit S, et al.

Appl Biochem Biotechnol, 2024 Jan;196(1):491-505.
PMID: 37145344 DOI: 10.1007/s12010-023-04550-6

The current study reports the synthesis of sustainable nano-hydroxyapatite (nHAp) using a wet chemical precipitation approach. The materials used in the green synthesis of nHAp were obtained from environmental biowastes such as HAp from eggshells and pectin from banana peels. The physicochemical characterization of obtained nHAp was carried out using different techniques. For instance, X-ray diffractometer (XRD) and FTIR spectroscopy were used to study the crystallinity and synthesis of nHAp respectively. In addition, the morphology and elemental composition of nHAP were studied using FESEM equipped with EDX. HRTEM showed the internal structure of nHAP and calculated its grain size which was 64 nm. Furthermore, the prepared nHAp was explored for its antibacterial and antibiofilm activity which has received less attention previously. The obtained results showed the potential of pectin-bound nHAp as an antibacterial agent for various biomedical and healthcare applications.
Acceleration analysis of repetitive multi-MeV ion beams from pulsed plasmas

Roshan MV, Roshan NV, Singh A

Appl Radiat Isot, 2023 Apr;194:110706.
PMID: 36738596 DOI: 10.1016/j.apradiso.2023.110706

Multi-MeV ion spectra reproduced with absolute spectral index agrees with the experimental data and meet the needs to critically analyze the repetitive pulsed plasma mode of applications. The ion acceleration parameter, (Ip.rp), predicts mean ion energy and that is related to the electric discharge components based upon the precision measurements. Proper selection of repetition rate offers a relatively stable proton beam to acquire the survival curves of irradiated targets. DSB rate for plasma focus operated at 1Hz, is 10DSB/s with corresponding surviving probability of the order of 10-5. The surviving fraction is likely to be more affected by higher dose frequencies.
Velopharyngeal stenosis, a late complication of radiotherapy

Lee SC, Tang IP, Singh A, Kumar SS, Singh S

Auris Nasus Larynx, 2009 Dec;36(6):709-11.
PMID: 19304419 DOI: 10.1016/j.anl.2009.02.002

Choanal stenosis has recently been recognized as a late complication of radiation therapy for nasopharyngeal carcinoma. The management of velopharyngeal stenosis is challenging with high risk of restenosis. We report a case of velopharyngeal stenosis post-radiotherapy and illustrated the use of mitomycin-C to prevent restenosis. Mitomycin-C application has being shown useful adjunct to surgical technique in managing nasopharyngeal stenosis for surgeons.
Fulltext Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1

Klionsky DJ, Abdel-Aziz AK, Abdelfatah S, Abdellatif M, Abdoli A, Abel S, et al.

Autophagy, 2021 Jan;17(1):1-382.
PMID: 33634751 DOI: 10.1080/15548627.2020.1797280

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.
Fulltext Changes in COVID-19 risk perceptions: methods of an internet survey conducted in six countries

Zhang F, Shih SF, Harapan H, Rajamoorthy Y, Chang HY, Singh A, et al.

BMC Res Notes, 2021 Nov 25;14(1):428.
PMID: 34823587 DOI: 10.1186/s13104-021-05846-8

OBJECTIVES: This study assessed changes in behaviors/attitudes related to the COVID-19. With the understanding that behaviors and vaccine decision-making could contribute to global spread of infectious diseases, this study collected several waves of internet-based surveys from individuals in the United States, mainland China, Taiwan, Malaysia, Indonesia, and India. The aims of this study were to (1) characterize the relationship between the epidemiology of disease and changes over time in risk perceptions, knowledge, and attitudes towards hygienic behaviors; (2) examine if risk perceptions affect acceptance of less-than-ideal vaccines; and (3) contrast adherence to public health recommendations across countries which have had different governmental responses to the outbreak.
DATA DESCRIPTION: We conducted cross-sectional online surveys in six countries from March 2020 to April 2021. By the end of June 2021, there will be six waves of surveys for the United States and China, and four waves for the rest of countries. There are common sets of questions for all countries, however, some questions were adapted to reflect local situations and some questions were designed intentionally for specific countries to capture different COVID-19 mitigation actions. Participants were asked about their adherence towards countermeasures, risk perceptions, and acceptance of a hypothetical vaccine for COVID-19.
Aerated Static Pile Composting for Industrial Biowastes: From Engineering to Microbiology

Keng ZX, Tan JJM, Phoon BL, Khoo CC, Khoiroh I, Chong S, et al.

Bioengineering (Basel), 2023 Aug 07;10(8).
PMID: 37627823 DOI: 10.3390/bioengineering10080938

This work demonstrated the feasibility of an industrial-scale aerated static pile composting system for treating one of the common biowastes-soybean curd residue. The mixing ratios of the feedstock were optimized to achieve a carbon-nitrogen ratio and a moisture level in the ranges of 25-35 and 60-70%, respectively. This open-air composting system required 6-7 months to obtain a mature compost. Solvita and seed germination tests further confirmed the maturity of the compost, with 25% compost extract concentration yielding the best germination index in the absence of phytotoxicity. The bacterial and fungal compositions of the compost piles were further examined with metagenomic analysis. Thermoactinomyces spp., Oceanobacillus spp., and Kroppenstedtia spp. were among the unique bacteria found, and Diutina rugosa, Thermomyces dupontii, and Candida taylorii were among the unique fungi found in the compost piles, suggesting the presence of good microorganisms for degrading the organic biowastes.
Fulltext Mesenchymal Stem Cell-Derived Extracellular Vesicles: Regenerative Potential and Challenges

Fuloria S, Subramaniyan V, Dahiya R, Dahiya S, Sudhakar K, Kumari U, et al.

Biology (Basel), 2021 Feb 25;10(3).
PMID: 33668707 DOI: 10.3390/biology10030172

Evidence suggests that stem cells exert regenerative potential via the release of extracellular vesicles. Mesenchymal stem cell extracellular vesicles (MSCEVs) offer therapeutic benefits for various pathophysiological ailments by restoring tissues. Facts suggest that MSCEV action can be potentiated by modifying the mesenchymal stem cells culturing methodology and bioengineering EVs. Limited clinical trials of MSCEVs have questioned their superiority, culturing quality, production scale-up and isolation, and administration format. Translation of preclinically successful MSCEVs into a clinical platform requires paying attention to several critical matters, such as the production technique, quantification/characterization, pharmacokinetics/targeting/transfer to the target site, and the safety profile. Keeping these issues as a priority, the present review was designed to highlight the challenges in translating preclinical MSCEV research into clinical platforms and provide evidence for the regenerative potential of MSCEVs in various conditions of the liver, kidney, heart, nervous system, bone, muscle, cartilage, and other organs/tissues.
AChE inhibitor: a regio- and stereo-selective 1,3-dipolar cycloaddition for the synthesis of novel substituted 5,6-dimethoxy spiro[5.3']-oxindole-spiro-[6.3″]-2,3-dihydro-1H-inden-1″-one-7-(substituted aryl)-tetrahydro-1H-pyrrolo[1,2-c][1,3]thiazole

Ashraf Ali M, Ismail R, Choon TS, Kumar RS, Osman H, Arumugam N, et al.

Bioorg Med Chem Lett, 2012 Jan 1;22(1):508-11.
PMID: 22142546 DOI: 10.1016/j.bmcl.2011.10.087

Pyrrolothiazolyloxindole analogues share vital pharmacological properties, considered useful in Alzheimer's disease (AD). The aim of this study was synthesis and evaluate pyralothiazolyloxindole analogues if possess acetyl cholinesterase (AChE) inhibitory activity. The easily accessible one-pot synthesis of these compounds resulted to be significantly less difficult and expensive than that of donepezil. Several compounds possess anti-cholinesterase activity in the order of micro and sub-micromolar. Particularly, compound was the most potent inhibitors of the series against acetyl cholinesterase enzyme with IC(50) 0.11μmol/L.
Role of Neurokinin B in gametogenesis and steroidogenesis of freshwater catfish, Clarias batrachus

Singh A, Lal B, Kumar P, Parhar IS, Millar RP

Cell Tissue Res, 2023 Aug;393(2):377-391.
PMID: 37278825 DOI: 10.1007/s00441-023-03788-0

Neurokinin B (NKB), a recently discovered neuropeptide, plays a crucial role in regulating the kiss-GnRH neurons in vertebrate's brain. NKB is also characterized in gonadal tissues; however, its role in gonads is poorly understood. Therefore, in the present study, the effects of NKB on gonadal steroidogenesis and gametogenesis through in vivo and in vitro approaches using NKB antagonist MRK-08 were evaluated. The results suggest that the NKB antagonist decreases the development of advanced ovarian follicles and germ cells in the testis. In addition, MRK-08 further reduces the production of 17β-estradiol in the ovary and testosterone in the testis under both in vivo and in vitro conditions in a dose-dependent manner. Furthermore, the in vitro MRK-08 treatment of gonadal explants attenuated the expression of steroidogenic marker proteins, i.e., StAR, 3β-HSD, and 17β-HSD dose-dependently. Moreover, the MAP kinase proteins, pERK1/2 & ERK1/2 and pAkt & Akt were also downregulated by MRK-08. Thus, the study suggests that NKB downregulates steroidogenesis by modulating the expressions of steroidogenic marker proteins involving ERK1/2 & pERK1/2 and Akt/pAkt signalling pathways. NKB also appears to regulate gametogenesis by regulating gonadal steroidogenesis in the catfish.
Correction to: Role of Neurokinin B in gametogenesis and steroidogenesis of freshwater catfish, Clarias batrachus

Singh A, Lal B, Kumar P, Parhar IS, Millar RP

Cell Tissue Res, 2023 Sep;393(3):595-596.
PMID: 37455268 DOI: 10.1007/s00441-023-03812-3
Molecular distribution, sources and potential health risks of fine particulate-bound polycyclic aromatic hydrocarbons during high pollution episodes in a subtropical urban city

Singh A, Banerjee T, Latif MT, Ramanathan S, Suradi H, Othman M, et al.

Chemosphere, 2023 Nov;340:139943.
PMID: 37625487 DOI: 10.1016/j.chemosphere.2023.139943

Abundance of fine particulate-bound 16 priority polycyclic aromatic hydrocarbons (PAHs) was investigated to ascertain its sources and potential carcinogenic health risks in Varanasi, India. The city represents a typical urban settlement of South Asia having particulate exposure manyfold higher than standard with reports of pollution induced mortalities and morbidities. Fine particulates (PM2.5) were monitored from October 2019 to May 2020, with 32% of monitoring days accounting ≥100 μgm-3 of PM2.5 concentration, frequently from November to January (99% of monitoring days). The concentration of 16 priority PAHs varied from 24.1 to 44.6 ngm-3 (mean: 33.1 ± 3.2 ngm-3) without much seasonal deviations. Both low (LMW, 56%) and high molecular weight (HMW, 44%) PAHs were abundant, with Fluoranthene (3.9 ± 0.4ngm-3) and Fluorene (3.5 ± 0.3ngm-3) emerged as most dominating PAHs. Concentration of Benzo(a)pyrene (B(a)P, 0.5 ± 0.1ngm-3) was lower than the national standard as it contributed 13% of total PAHs mass. Diagnostic ratios of PAH isomers indicate predominance of pyrogenic sources including emissions from biomass burning, and both from diesel and petrol-driven vehicles. Source apportionment using receptor model revealed similar observation of major PAHs contribution from biomass burning and fuel combustion (54% of source contribution) followed by coal combustion for residential heating and cooking purposes (44%). Potential toxicity of B[a]P equivalence ranged from 0.003 to 1.365 with cumulative toxicity of 2.13ngm-3. Among the PAH species, dibenzo[h]anthracene contributed maximum toxicity followed by B[a]P, together accounting 86% of PAH induced carcinogenicity. Incremental risk of developing cancer through lifetime exposure (ILCR) of PAHs was higher in children (3.3 × 10-4) with 56% contribution from LMW PAHs, primarily through ingestion and dermal contact. Adults in contrast, were more exposed to inhale airborne PAHs with cumulative ILCR of 2.2 × 10-4. However, ILCR to PM2.5 exposure is probably underestimated considering unaccounted metal abundance thus, require source-specific control measures.
Fulltext Worldwide Survey of COVID-19-Associated Arrhythmias

Coromilas EJ, Kochav S, Goldenthal I, Biviano A, Garan H, Goldbarg S, et al.

Circ Arrhythm Electrophysiol, 2021 03;14(3):e009458.
PMID: 33554620 DOI: 10.1161/CIRCEP.120.009458

[Figure: see text].
Fulltext A survey of psychological distress among Bangladeshi people during the COVID-19 pandemic

Marzo RR, Singh A, Mukti RF

Clin Epidemiol Glob Health, 2021;10:100693.
PMID: 33462563 DOI: 10.1016/j.cegh.2020.100693

INTRODUCTION: Previous studies conducted on the psychological impact of infectious outbreaks have found heavy psychological burdens among general population with more severe affect in the current pandemic. The main aim of this study is to examine the level of psychological distress during COVID-19 in Bangladesh and explore factors associated with higher psychological distress.
METHODS: An internet-based, cross-sectional survey was conducted from March to April 2020 in Bangladesh among adults 18 years old and above using structured online questionnaires distributed through emails and other social media throughout Bangladesh with an overall response rate of 34%. Modified version of the Covid19 peritraumatic distress index (CPDI) was used to measure distress. Univariate and Bivariate analysis was used to estimate prevalence of CPDI symptoms and test for the associations between CPDI and the exposure variables. Logistic regression analyses were used to estimate the odds ratios of our outcome variable by exposure variables.
RESULTS: Overall, 44.3% of respondents were suffering from mild to moderate distress and 9.5% were suffering from severe distress. Female respondents were 2.435 times more likely to suffer from CPDI mild to severe distress than males. As compared to Dhaka and Mymensing region of Bangladesh, odds of distress was 1.945 times more in Chittagong/Sylhet region (p-value = 0.035).
CONCLUSION: Large proportion of adult population in Bangladesh are experiencing psychological distress, with level of distress varies by different symptoms and predictors. This study suggest the need to develop comprehensive crisis prevention system including epidemiological monitoring, screening, and referral with targeted intervention to reduce psychological distress.

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