Otun Saha

Dr. Otun Saha

orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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27 July 2020 in Microorganisms
Verified
Journal Article
Open access
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OSOtun Saha
Otun Saha
MHM. Nazmul Nazmul Hoque
M. Nazmul Nazmul Hoque
OIOvinu Kibria Islam
Ovinu Kibria Islam
MRMd. Mizanur Rahaman
Md. Mizanur Rahaman
MSMunawar Sultana
Munawar Sultana
MHM. Anwar Hossain
M. Anwar Hossain
The avian pathogenic Escherichia coli (APEC) strains are the chief etiology of colibacillosis worldwide. The present study investigated the circulating phylotypes, existence of virulence genes (VGs), and antimicrobial resistance (AMR) in 392 APEC isolates, obtained from 130 samples belonged to six farms using both phenotypic and PCR-based molecular approaches. Congo red binding (CRB) assay confirmed 174 APEC isolates which were segregated into ten, nine, and eight distinct genotypes by RAPD assay (discriminatory index, DI = 0.8707), BOX-PCR (DI = 0.8591) and ERIC-PCR (DI = 0.8371), respectively. The combination of three phylogenetic markers (chuA, yjaA and DNA fragment TspE4.C2) classified APEC isolates into B23 (37.36%), A1 (33.91%), D2 (11.49%), B22 (9.20%), and B1 (8.05%) phylotypes. Majority of the APEC isolates (75–100%) harbored VGs (ial, fimH, crl, papC, and cjrC). These VGs (papC and cjrC) and phylotypes (D2 and B2) of APEC had significant (p = 0.004) association with colibacillosis. Phylogenetic analysis showed two distinct clades (clade A and clade B) of APEC, where clade A had 98–100% similarity with E. coli APEC O78 and E. coli EHEC strains, and clade B had closest relationship with E. coli O169:H41 strain. Interestingly, phylogroups B2 and D2 were found in the APEC strains of both clades, while the strains from phylogroups A1 and B1 were found in clade A only. In this study, 81.71% of the isolates were biofilm formers, and possessed plasmids of varying ranges (1.0 to 54 kb). In vitro antibiogram profiling revealed that 100% isolates were resistant to ≥3 antibiotics, of which 61.96%, 55.24%, 53.85%, 51.16% and 45.58% isolates in phylotypes B1, D2, B22, B23, and A1, respectively, were resistant to these antimicrobials. The resistance patterns varied among different phylotypes, notably in phylotype B22, showing the highest resistance to ampicillin (90.91%), nalidixic acid (90.11%), tetracycline (83.72%), and nitrofurantoin (65.12%). Correspondence analysis also showed significant correlation among phylotypes with CRB (p = 0.008), biofilm formation (p = 0.02), drug resistance (p = 0.03), and VGs (p = 0.06). This report demonstrated that B2 and A1 phylotypes are dominantly circulating APEC phylotypes in Bangladesh; however, B2 and D2 are strongly associated with the pathogenicity. A high prevalence of antibiotic-resistant APEC strains from different phylotypes suggest the use of organic antimicrobial compounds, and/or metals, and the rotational use of antibiotics in poultry farms in Bangladesh.

22 September 2022 in Veterinary Medicine and Science
Verified
Journal Article
Open access
MHM. Nazmul Nazmul Hoque
M. Nazmul Nazmul Hoque
ATAnup Kumar Talukder
Anup Kumar Talukder
OSOtun Saha
Otun Saha
MHMehedi Hasan
Mehedi Hasan
MSMunawar Sultana
Munawar Sultana
ZDZiban Chandra Das
Ziban Chandra Das
Background: Staphylococcusspp. are the major causal agents of mastitis in dairy animals worldwide leading to profound economic losses and public health threats. Recently,Staphylococcus aureushas emerged as a multidrug resistant and zoonotic pathogen. This study aimed to characterizeS. aureusin subclinical mastitis (SCM) milk samples of riverine buffaloes in Bangladesh through antibiogram and virulence gene(s) profiling, and 16S rRNA gene sequencing.Method: We characterizedS. aureusin SCM milk samples (N = 500) of riverine buffaloes through antibiogram and virulence gene(s) profiling, and 16S rRNA gene sequencing.Results: Out of 500 milk samples tested, 188 (37.6%) were found positive for SCM. From 188 SCM samples, 291 isolates were obtained with a prevalence ofS. aureusin 37.4% (109/291) isolates. Phylogenetic analysis revealed the evolutionary divergence ofS. aureusisolates in bubaline SCM milk samples. The antibiogram profiling showed that about 96.0%S. aureusisolates were multidrug resistant (MDR). Notably, 29 and 16 isolates harboured methicillin‐resistant (mecA) and panton‐valentine leucocidin (pvl) genes, respectively, and 46 plasmid‐bearing isolates were MDR. NineStaphylococcalenterotoxins (SEs/SEls) includingsea(11.9%),sec(7.4%),sed(4.6%),seg(3.7%), andseh(3.7%) were detected with 72.48% toxinotypes comprising a single gene.Conclusion: This study therefore suggestsS. aureusas the single‐most aetiology (∼37.0%) of SCM in riverine buffaloes, and emergence of MDR, enterotoxin producing, and virulentS. aureusstrains could impose potential threats to animal welfare and public health.

23 September 2021 in Viruses
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Journal Article
Open access
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AIAriful Islam
Ariful Islam
JFJinnat Ferdous
Jinnat Ferdous
SIShariful Islam
Shariful Islam
Md Abu SayeedMd Abu Sayeed
Md Abu Sayeed
SCShusmita Dutta Choudhury
Shusmita Dutta Choudhury
TSTahmina Shirin
Tahmina Shirin
Diverse coronavirus (CoV) strains can infect both humans and animals and produce various diseases. CoVs have caused three epidemics and pandemics in the last two decades, and caused a severe impact on public health and the global economy. Therefore, it is of utmost importance to understand the emergence and evolution of endemic and emerging CoV diversity in humans and animals. For diverse bird species, the Infectious Bronchitis Virus is a significant one, whereas feline enteric and canine coronavirus, recombined to produce feline infectious peritonitis virus, infects wild cats. Bovine and canine CoVs have ancestral relationships, while porcine CoVs, especially SADS-CoV, can cross species barriers. Bats are considered as the natural host of diverse strains of alpha and beta coronaviruses. Though MERS-CoV is significant for both camels and humans, humans are nonetheless affected more severely. MERS-CoV cases have been reported mainly in the Arabic peninsula since 2012. To date, seven CoV strains have infected humans, all descended from animals. The severe acute respiratory syndrome coronaviruses (SARS-CoV and SARS-CoV-2) are presumed to be originated in Rhinolopoid bats that severely infect humans with spillover to multiple domestic and wild animals. Emerging alpha and delta variants of SARS-CoV-2 were detected in pets and wild animals. Still, the intermediate hosts and all susceptible animal species remain unknown. SARS-CoV-2 might not be the last CoV to cross the species barrier. Hence, we recommend developing a universal CoV vaccine for humans so that any future outbreak can be prevented effectively. Furthermore, a One Health approach coronavirus surveillance should be implemented at human-animal interfaces to detect novel coronaviruses before emerging to humans and to prevent future epidemics and pandemics.

12 February 2024 in Informatics in Medicine Unlocked
Verified
Journal Article
Open access
NSNoimul Hasan Siddiquee
Noimul Hasan Siddiquee
IHIfteker Hossain
Ifteker Hossain
ETEnamul Kabir Talukder
Enamul Kabir Talukder
SNSyed Afnan Arefin Nirob
Syed Afnan Arefin Nirob
MSManjurul Islam Shourav
Manjurul Islam Shourav
OSOtun Saha
Otun Saha

9 November 2021 in Transboundary and Emerging Diseases
Verified
Journal Article
Open access
PDF file
AIAriful Islam
Ariful Islam
JFJinnat Ferdous
Jinnat Ferdous
SIShariful Islam
Shariful Islam
Md Abu SayeedMd Abu Sayeed
Md Abu Sayeed
Md. Kaisar RahmanMd. Kaisar Rahman
Md. Kaisar Rahman
TSTahmina Shirin
Tahmina Shirin
The exact origin of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and source of introduction into humans has not been established yet, though it might be originated from animals. Therefore, we conducted a literature review to understand the putative reservoirs, transmission dynamics, and susceptibility patterns of SARS-CoV-2 in animals. Rhinolophus bats are presumed to be natural progenitors of SARS-CoV-2 related viruses. Initially, pangolin was thought to be the source of spillover to humans, but they might be infected by human or other animal species. So, the virus spillover pathways to humans remain unknown. Human-to-animal transmission has been testified in pet, farmed, zoo, and free-ranging wild animals. Infected animals can transmit the virus to other animals in natural settings like mink-to-mink, and mink-to-cat transmission. Animal-to-human transmission is not a persistent pathway, while mink-to-human transmission continues to be illuminated. Multiple companions and captive wild animals were infected by an emerging alpha variant of concern (B.1.1.7 lineage) whereas Asiatic lions were infected by delta variant, (B.1.617.2). To date, multiple animal species- cat, ferrets, non-human primates, hamsters, and bats, showed high susceptibility to SARS-CoV-2 in the experimental condition, while swine, poultry, cattle showed no susceptibility. The founding of SARS-CoV-2 in wild animal reservoirs can confront the control of the virus in humans and might carry a risk to the welfare and conservation of wildlife as well. We suggest vaccinating pets and captive animals to stop spillovers and spillback events. We recommend sustainable one health surveillance at the animal-human-environmental interface to detect and prevent future epidemics and pandemics by Disease X. This article is protected by copyright. All rights reserved

1 January 2024 in Bioinformatics and Biology Insights
Verified
Journal Article
Open access
OSOtun Saha
Otun Saha
NSNoimul Hasan Siddiquee
Noimul Hasan Siddiquee
RARahima Akter
Rahima Akter
NSNikkon Sarker
Nikkon Sarker
UBUditi Paul Bristi
Uditi Paul Bristi
MAMir Salma Akter
Mir Salma Akter
The Nipah virus (NiV) belongs to the Henipavirus genus is a serious public health concern causing numerous outbreaks with higher fatality rate. Unfortunately, there is no effective medication available for NiV. To investigate possible inhibitors of NiV infection, we used in silico techniques to discover treatment candidates in this work. As there are not any approved treatments for NiV infection, the NiV-enveloped attachment glycoprotein was set as target for our study, which is responsible for binding to and entering host cells. Our in silico drug design approach included molecular docking, post-docking molecular mechanism generalised born surface area (MM-GBSA), absorption, distribution, metabolism, excretion/toxicity (ADME/T), and molecular dynamics (MD) simulations. We retrieved 418 phytochemicals associated with the neem plant ( Azadirachta indica) from the IMPPAT database, and molecular docking was used to ascertain the compounds’ binding strength. The top 3 phytochemicals with binding affinities of −7.118, –7.074, and −6.894 kcal/mol for CIDs 5280343, 9064, and 5280863, respectively, were selected for additional study based on molecular docking. The post-docking MM-GBSA of those 3 compounds was −47.56, –47.3, and −43.15 kcal/mol, respectively. As evidence of their efficacy and safety, all the chosen drugs had favorable toxicological and pharmacokinetic (Pk) qualities. We also performed MD simulations to confirm the stability of the ligand-protein complex structures and determine whether the selected compounds are stable at the protein binding site. All 3 phytochemicals, Quercetin (CID: 5280343), Cianidanol (CID: 9064), and Kaempferol (CID: 5280863), appeared to have outstanding binding stability to the target protein than control ribavirin, according to the molecular docking, MM-GBSA, and MD simulation outcomes. Overall, this work offers a viable approach to developing novel medications for treating NiV infection.