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Objective: Multidrug-resistant (MDR) Acinetobacter baumannii is a major issue within healthcare facilities in Bangladesh due to its frequent association with hospital-acquired infections. In this study we report on a carbapenem-resistant draft genome sequence of an A. baumannii BD20 sample isolated from an infected wound in Bangladesh. Methods: A. baumannii BD20 was isolated from an infected burn wound. Whole-genome sequencing was carried out and annotated using PGAP and Prokka. Sequence type, antimicrobial resistance genes, virulence factor genes, and metal resistance genes were investigated. Core genome multilocus sequence typing–based phylogenomic analysis between A. baumannii BD20 and 213 A. baumannii strains retrieved from the NCBI GenBank database was performed using the BacWGSTdb 2.0 server. Results: A. baumannii BD20 (MLST 491) was resistant to all the antibiotics tested, except for colistin and polymyxin B. Along with many other antibiotic resistance genes, the isolate harbored three classes of beta lactamase–producing genes: blaGES-11 (class A), blaOXA-69 (class D), blaADC-10 (class C), and blaADC-11 (class C). Additionally, the strain carried several virulence genes and metal resistance determinants, which may contribute to its increased virulence. Core genome MLST–based phylogenomic analysis revealed that A. baumannii BD20 was closely related to another ST491 strain isolated from Singapore. Conclusions: The findings of this study underscore the growing challenge of MDR A. baumannii, emphasizing the need for vigilant surveillance and infection-control measures in healthcare settings in order to address these emerging threats effectively.

ABSTRACT: Objectives: Pseudomonas aeruginosa (P. aeruginosa) stands out as a key culprit in the colonization of burn wounds, instigating grave infections of heightened severity. In this study, we have performed comparative whole genome analysis of a difficult to treat extensively drug resistant P. aeruginosa isolated from a burn patient in order to elucidate genomic diversity, molecular patterns, mechanisms and genes responsible for conferring antimicrobial resistance and virulence. Method: P. aeruginosa SHNIBPS206 was isolated from an infected burn wound of a critically injured burn patient. Whole genome sequencing was carried out and annotated with Prokka. Sequence type, serotype, antimicrobial resistance genes and mechanisms, virulence genes, metal resistance genes and CRISPR/Cas systems were investigated. Later, pangenome analysis was carried out to find out genomic diversity. Result: P. aeruginosa SHNIBPS206 (MLST 357, Serotype O11) was resistant to 14 antibiotics including carbapenems and harboured all four classes of beta lactamase producing genes: Class A (blaPME-1, blaVEB-9), Class B (blaNDM-1), Class C (blaPDC-11) and Class D (blaOXA-846). Mutational analysis of Porin D gave valuable insights. Several efflux pump, virulence and metal resistance genes were also detected. Pangenome analysis revealed high genomic diversity among different strains of P. aeruginosa. Conclusion: To our knowledge, this is the first report of an extensively drug resistant ST 357 P. aeruginosa from Bangladesh, which is an epidemic high-risk P. aeruginosa clone. Further research and in-depth comprehensive studies are required to investigate the prevalence of such high-risk clone of P. aeruginosa in Bangladesh.

Abstract The increasing antimicrobial resistance in Providencia stuartii (P. stuartii) worldwide, particularly concerning for immunocompromised and burn patients, has raised concern in Bangladesh, where the significance of this infectious opportunistic pathogen had been previously overlooked, prompting a need for investigation. The two strains of P. stuartii (P. stuartii SHNIBPS63 and P. stuartii SHNIBPS71) isolated from wound swab of two critically injured burn patients were found to be multidrug-resistant and P. stuartii SHNIBPS63 showed resistance to all the 22 antibiotics tested as well as revealed the co-existence of bla VEB-6 (Class A), bla NDM-1 (Class B), bla OXA-10 (Class D) beta lactamase genes. Complete resistance to carbapenems through the production of NDM-1, is indicative of an alarming situation as carbapenems are considered to be the last line antibiotic to combat this pathogen. Both isolates displayed strong biofilm-forming abilities and exhibited resistance to copper, zinc, and iron, in addition to carrying multiple genes associated with metal resistance and the formation of biofilms. The study also encompassed a pangenome analysis utilizing a dataset of eighty-six publicly available P. stuartii genomes (n = 86), revealing evidence of an open or expanding pangenome for P. stuartii. Also, an extensive genome-wide analysis of all the P. stuartii genomes revealed a concerning global prevalence of diverse antimicrobial resistance genes, with a particular alarm raised over the abundance of carbapenem resistance gene bla NDM-1. Additionally, this study highlighted the notable genetic diversity within P. stuartii, significant informations about phylogenomic relationships and ancestry, as well as potential for cross-species transmission, raising important implications for public health and microbial adaptation across different environments.

Abstract In the context of anti-cellular catalytic permutations, the development of thermally-induced nanotechnology is of great importance. In this study, iron oxides (Fe2O3) decorated silver (Ag) core–shell nanocomposite was prepared using a green thermal decomposition process without using any additional chemicals. The nanocomposite was characterized for its composition, phase interactions, morphology, and stability using spectroscopic, thermogravimetric, and microscopic techniques. The resultant nanocomposite were also investigated against different types of bacteria and cancer cell lines. Both Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Klebsiella spp., E. coli, and Pseudomonas) growth was inhibited by the Ag/Fe2O3 nanocomposite. The highest 19 mm zone of inhibition (ZOI) was found for Staphylococcus aureus by the combined effect of Ag and Fe2O3. The antibiofilm efficacy of the prepared nanocomposites showed biofilm destruction of 82.56% Staphylococcus aureus and 51.06% Klebsiella spp. Furthermore, the nanocomposite resulted in 80–90% death of Hela and BHK-21 cells but displayed lower cell toxicity in the case of the Vero cell line. This pathway of nanocomposites preparation with particle surface engineering would open new doors in the fields of nanobiotechnology and nanobiomedical applications.

Abstract Respiratory syncytial virus (RSV) is a common respiratory pathogen that causes mild cold-like symptoms and severe lower respiratory tract infections, causing hospitalizations in children, the elderly and immunocompromised individuals. Due to genetic variability, this virus causes life-threatening pneumonia and bronchiolitis in young infants. Thus, we examined 3600 whole genome sequences submitted to GISAID by 31 December 2022 to examine the genetic variability of RSV. While RSVA and RSVB coexist throughout RSV seasons, RSVA is more prevalent, fatal, and epidemic-prone in several countries, including the United States, the United Kingdom, Australia, and China. Additionally, the virus's attachment glycoprotein and fusion protein were highly mutated, with RSVA having higher Shannon entropy than RSVB. The genetic makeup of these viruses contributes significantly to their prevalence and epidemic potential. Several strain-specific SNPs co-occurred with specific haplotypes of RSVA and RSVB, followed by different haplotypes of the viruses. RSVA and RSVB have the highest linkage probability at loci T12844A/T3483C and G13959T/C2198T, respectively. The results indicate that specific haplotypes and SNPs may significantly affect their spread. Overall, this analysis presents a promising strategy for tracking the evolving epidemic situation and genetic variants of RSV, which could aid in developing effective control, prophylactic, and treatment strategies.

Abstract The multifactorial nature of Pseudomonas aeruginosa biofilm development and genomic variabilities implicates its resistance to conventional antimicrobials and virulence. Therefore, genetic determinants need to be extensively studied to block the early steps of biofilm or already formed biofilms. In this study, a total of 20 multidrug resistant (MDR) clinical P. aeruginosa isolates were evaluated for their biofilm forming abilities and related genes. Of the isolates tested, all of them showed surface attachment tendencies in nutrient limiting conditions, and classified as strong (SBF = 45%), moderate (MBF = 30%) and weak (WBF = 25%) biofilm formers. Complete genome sequencing of representative strong (DMC-27b), moderate (DMC-20c) and weak biofilm former (DMC-30b) isolates was performed. Analysis of biofilm related genes in the sequenced genomes revealed that, 80 of the 88 biofilm related genes possess 98–100% sequence identity to the reference PAO1 strain. Complete and partial sequence data of LecB proteins from tested isolates indicate that isolates containing PA14-like LecB sequences produced strong biofilms. All of the 7 pel operon protein coding genes in weak biofilm former isolate 30b showed significant nucleotide sequence variation with other tested isolates, and their corresponding proteins are 99% identical with the pel operon proteins of PA7. Bioinformatics analyses identified divergent sequence and structural features that separate PA7 like pel operon proteins from reference PAO1-like pel operon. Congo red and pellicle forming assays revealed that the sequence and structure variations may have interfered with the Pel production pathway and resulted in impaired Pel production in isolate 30b that has a PA7 like pel operon. Expression analysis also showed that both pelB and lecB genes were about 5 to 6 folds upregulated after 24 h in SBF 27b in comparison with WBF 30b. Our findings indicate significant genomic divergence in biofilm related genes of P. aeruginosa strains that affect their biofilm phenotypes.

The majority of the world's nations have faced the second-highest cancer mortality rate. The main causes of cancer include an unbalanced diet, genetic factors, and a few specific environmental substances. Recently, a variety of substances have been used to treat cancer, and some are still being studied. It has long been known that the mid of the twentieth century that plant and marine species create a wide range of chemically and physiologically diverse metabolites with a variety of biological effects, including anticancer, anti-inflammatory, antioxidant, antibacterial, antifouling and so on. The focus of this study is on newly found compounds from plant and marine sources that have potent anticancer effects.

In recent decades, acceptance of nanoparticles (NPs) in therapeutic applications has increased because of their outstanding physicochemical features. By overcoming the drawbacks of conventional therapy, the utilization of metal NPs, metal-oxide, or metal supported nanomaterials have shown to have significant therapeutic applications in medicine. This is proved by a lot of clinical and laboratory investigations that show improved treatment outcomes, site-specific drug delivery, and fewer side effects compared to traditional medicine. The metal NPs interaction with living cells (animal and plant) showed many ways to develop therapeutic models with the NPs. Despite all of the advancements that science has achieved, there is still a need to find out their performance for long-term use to solve modern challenges. In this regard, the present documentation reviews some potential metals, including silver (Ag), gold (Au), zinc (Zn), copper (Cu), iron (Fe), and nickel (Ni) NPs, as therapeutic agents in various areas such as anticancer, antimicrobial, antidiabetic, and applicable for the treatment of many other diseases. Depending on the outstanding ongoing research and practical trials, metal-based NPs can be considered the hope of prospective modern therapeutic areas.

Abstract Gallic acid (GA) is a phenolic molecule found naturally in a wide range of fruits as well as in medicinal plants. It has many health benefits due to its antioxidant properties. This study focused on finding out the neurobiological effects and mechanisms of GA using published data from reputed databases. For this, data were collected from various sources, such as PubMed/Medline, Science Direct, Scopus, Google Scholar, SpringerLink, and Web of Science. The findings suggest that GA can be used to manage several neurological diseases and disorders, such as Alzheimer’s disease, Parkinson’s disease, strokes, sedation, depression, psychosis, neuropathic pain, anxiety, and memory loss, as well as neuroinflammation. According to database reports and this current literature-based study, GA may be considered one of the potential lead compounds to treat neurological diseases and disorders. More preclinical and clinical studies are required to establish GA as a neuroprotective drug.

Genomes may now be sequenced in a matter of weeks, leading to an influx of “hypothetical” proteins (HP) whose activities remain a mystery in GenBank. The information included inside these genes has quickly grown in prominence. Thus, we selected to look closely at the structure and function of an HP (AFF25514.1; 246 residues) from Pasteurella multocida (PM) subsp. multocida str. HN06. Possible insights into bacterial adaptation to new environments and metabolic changes might be gained by studying the functions of this protein. The PM HN06 2293 gene encodes an alkaline cytoplasmic protein with a molecular weight of 28352.60 Da, an isoelectric point (pI) of 9.18, and an overall average hydropathicity of around −0.565. One of its functional domains, tRNA (adenine (37)-N6)-methyltransferase TrmO, is a S -adenosylmethionine (SAM)-dependent methyltransferase (MTase), suggesting that it belongs to the Class VIII SAM-dependent MTase family. The tertiary structures represented by HHpred and I-TASSER models were found to be flawless. We predicted the model’s active site using the Computed Atlas of Surface Topography of Proteins (CASTp) and FTSite servers, and then displayed it in 3 dimensional (3D) using PyMOL and BIOVIA Discovery Studio. Based on molecular docking (MD) results, we know that HP interacts with SAM and S -adenosylhomocysteine (SAH), 2 crucial metabolites in the tRNA methylation process, with binding affinities of 7.4 and 7.5 kcal/mol, respectively. Molecular dynamic simulations (MDS) of the docked complex, which included only modest structural adjustments, corroborated the strong binding affinity of SAM and SAH to the HP. Evidence for HP’s possible role as an SAM-dependent MTase was therefore given by the findings of Multiple sequence alignment (MSA), MD, and molecular dynamic modeling. These in silico data suggest that the investigated HP might be used as a useful adjunct in the investigation of Pasteurella infections and the development of drugs to treat zoonotic pasteurellosis.

Abstract Cancer is the second most killer worldwide causing millions of people to lose their lives every year. In the case of women, breast cancer takes away the highest proportion of mortality rate than other cancers. Due to the mutation and resistance-building capacity of different breast cancer cell lines against conventional therapies, this death rate is on the verge of growth. New effective therapeutic compounds and treatment method is the best way to look out for in this critical time. For instance, new synthetic derivatives/ analogues synthesized from different compounds can be a ray of hope. Numerous synthetic compounds have been seen enhancing the apoptosis and autophagic pathway that directly exerts cytotoxicity towards different breast cancer cell lines. To cease the ever-growing resistance of multi-drug resistant cells against anti-breast cancer drugs (Doxorubicin, verapamil, tamoxifen) synthetic compounds may play a vital role by increasing effectivity, showing synergistic action. Many recent and previous studies have reported that synthetic derivatives hold potentials as an effective anti-breast cancer agent as they show great cytotoxicity towards cancer cells, thus can be used even vastly in the future in the field of breast cancer treatment. This review aims to identify the anti-breast cancer properties of several synthetic derivatives against different breast cancer and multi-drug-resistant breast cancer cell lines with their reported mechanism of action and effectivity.

Lung cancer is the primary cause of cancer related deaths worldwide. Limited therapeutic options and resistance to existing drugs are the major hindrances to the clinical success of this cancer. In the past decade, several studies showed the role of microRNA (miRNA) driven cell cycle regulation in lung cancer progression. Therefore, these small nucleotide molecules could be utilized as promising tools in lung cancer therapy. In this review, we highlighted the recent advancements in lung cancer therapy using cell cycle linked miRNAs. By highlighting the roles of the specific cell cycle core regulators affiliated miRNAs in lung cancer, we further outlined how these miRNAs can be explored in early diagnosis and treatment strategies to prevent lung cancer. With the provided information from our review, more medical efforts can ensure a potential breakthrough in miRNA-based lung cancer therapy.

ABSTRACT: Objectives: Nosocomial carbapenem-resistant Acinetobacter baumannii is a challenge in the treatment of intensive care unit (ICU) patients. The presence of antimicrobial resistance genes (ARGs) and mobile genetic elements can further complicate effects to combat antibiotic resistance in this post-antibiotic era. The aim of this study was to analyse the molecular basis of carbapenem resistance in A. baumannii strain DMC-32a. Methods: Strain DMC-32a, isolated from a wound swab of an ICU patient, was screened phenotypically and genotypically for carbapenem resistance. The isolate was subjected whole-genome sequencing (WGS) to investigate the resistance mechanisms. Results: Strain DMC-32a was resistant to all tested antibiotics belonging to seven classes, except for the polymyxins. MICs determined against imipenem and meropenem were 512 mg/L and >512 mg/L, respectively. Gene-specific PCR confirmed the presence of blaNDM-1 and intI1. WGS confirmed the isolate as sequence type ST1053, the presence of four classes of β-lactamases [A (blaPER-7, blaTEM-116), B (blaNDM-1), C (blaADC-26) and D (blaOXA-23, blaOXA-51)], and four genes encoding aminoglycoside-modifying enzymes [aph(6)-Id, aph(3′′)-Ib, aph(3′)-VI and ant(3′′)-IIc] conferring resistance to streptomycin, amikacin, kanamycin and spectinomycin. The analysis also confirmed the presence of a class 1 integron gene cassette harbouring ARGs to rifamycin (arr-2) and phenicols (cmlA5). No plasmid replicon was found from the sequence data. Conclusion: The co-existence of four β-lactamase classes in A. baumannii DMC-32a has not been reported previously from Bangladesh and not in this ST elsewhere. The emergence of such a nosocomial pathogen creates the need for effective therapeutics for critically-ill patients and for controlling hospital-acquired infections.

Abstract Background Antioxidants have protective capacity, and can be used combinedly with other substances. Both, ascorbic acid (AA) and phytol (PHY) have many important biological activities, including antioxidant, anti-inflammatory, and organ protective activity. Recently, PHY has been found to exert an anti-pyretic effect in a mouse model. This study aims to evaluate the combined effects of AA and/or PHY with paracetamol (PARA) in Brewer’s yeast-induced fever mice model. Methods AA (125 mg/kg) and/or PHY (200 mg/kg) were orally co-treated with the PARA (100 mg/kg, p.o.) in Brewer’s yeast-induced fever Swiss mice. Data were analyzed by using GraphPadPrism software (version: 6.0), considering p

A new strain of the beta coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is solely responsible for the ongoing coronavirus disease 2019 (COVID-19) pandemic. Although several studies suggest that the spike protein of this virus interacts with the cell surface receptor, angiotensin-converting enzyme 2 (ACE2), and is subsequently cleaved by TMPRSS2 and FURIN to enter into the host cell, conclusive insight about the interaction pattern of the variants of these proteins is still lacking. Thus, in this study, we analyzed the functional conjugation among the spike protein, ACE2, TMPRSS2, and FURIN in viral pathogenesis as well as the effects of the mutations of the proteins through the implementation of several bioinformatics approaches. Analysis of the intermolecular interactions revealed that T27A (ACE2), G476S (receptor-binding domain [RBD] of the spike protein), C297T (TMPRSS2), and P812S (cleavage site for TMPRSS2) coding variants may render resistance in viral infection, whereas Q493L (RBD), S477I (RBD), P681R (cleavage site for FURIN), and P683W (cleavage site for FURIN) may lead to increase viral infection. Genotype-specific expression analysis predicted several genetic variants of ACE2 (rs2158082, rs2106806, rs4830971, and rs4830972), TMPRSS2 (rs458213, rs468444, rs4290734, and rs6517666), and FURIN (rs78164913 and rs79742014) that significantly alter their normal expression which might affect the viral spread. Furthermore, we also found that ACE2, TMPRSS2, and FURIN proteins are functionally co-related with each other, and several genes are highly co-expressed with them, which might be involved in viral pathogenesis. This study will thus help in future genomics and proteomics studies of SARS-CoV-2 and will provide an opportunity to understand the underlying molecular mechanism during SARS-CoV-2 pathogenesis.

Scientific evidence suggests that quercetin (QUR) has anxiolytic-like effects in experimental animals. However, the mechanism of action responsible for its anxiolytic-like effects is yet to be discovered. The goal of this research is to assess QUR’s anxiolytic effects in mouse models to explicate the possible mechanism of action. After acute intraperitoneal (i.p.) treatment with QUR at a dose of 50 mg/kg (i.p.), behavioral models of open-field, hole board, swing box, and light–dark tests were performed. QUR was combined with a GABAergic agonist (diazepam) and/or antagonist (flumazenil) group. Furthermore, in silico analysis was also conducted to observe the interaction of QUR and GABA (α5), GABA (β1), and GABA (β2) receptors. In the experimental animal model, QUR had an anxiolytic-like effect. QUR, when combined with diazepam (2 mg/kg, i.p.), drastically potentiated an anxiolytic effect of diazepam. QUR is a more highly competitive ligand for the benzodiazepine recognition site that can displace flumazenil (2.5 mg/kg, i.p.). In all the test models, QUR acted similar to diazepam, with enhanced effects of the standard anxiolytic drug, which were reversed by pre-treatment with flumazenil. QUR showed the best interaction with the GABA (α5) receptor compared to the GABA (β1) and GABA (β2) receptors. In conclusion, QUR may exert an anxiolytic-like effect on mice, probably through the GABA-receptor-interacting pathway.

MicroRNAs play a crucial role in tumorigenesis, tumor progression, and metastasis, and thus they contribute in development of different malignancies including cervical cancer (CC) and colorectal cancer (CRC). Through integrated strategies of computational biology, this study aims to identify prognostic biomarkers responsible for CRC and CC prognosis, and potential therapeutic agents to halt the progression of these cancers. Expression analysis of miRNA datasets of CRC and CC identified 17 differentially expressed miRNAs (DEMs). SYNPO2, NEGR1, FGF7, LIFR, RUNX1T1, CFL2, BNC2, EPHB2, PMAIP1, and CDC25A differentially expressed genes (DEGs) regulated by these DEMs were classified as candidate genes responsible for CRC and CC. Down-regulation of Synaptopodin-2 (SYNPO2) is involved in emergence and progression of these cancers by activating ER, PI3K/AKT, and EMT pathways as well as by suppressing DNA damage response, and cell cycle pathways. Higher methylation rate in promoter region of SYNPO2 could be a possible reason for lowering the expression of SYNPO2 in tumor stages. Hence, the lower expression of SYNPO2 is associated with poor prognosis of CRC and CC and could function as prognostic biomarker and therapeutic target. Fourteen transcription factors were recognized which can activate/inhibit the transcription of SYNPO2 and may be a potential target to regulate expression of SYNPO2 in CRC and CC. Retinoic acid and Estradiol were identified as putative therapeutic drugs for CRC and CC patients. This study will thus help in understanding the underlying molecular events in CRC and CC that may improve the detection of malignant lesions in primary screening and will broaden the clinical applications.

The scientific explorations of nanoparticles for their inherent therapeutic potencies as antimicrobial and antiviral agents due to increasing incidences of antibiotic resistance have gained more attention in recent time. This factor amongst others necessitates the search for newer and more effective antimicrobial agents. Several investigations have demonstrated the prospects of nanoparticles in the treatment of various microbial infections. The therapeutic applications of nanoparticles as either delivery agent or broad spectrum inhibition agents in viral and microbial investigations can no longer be overlooked. Their large surface area to volume ratio made them an indispensable substance as delivery agents in many respect. Various materials have been used for the synthesis of nanoparticles with unique properties channelised to meet specific therapeutic requirement. This review focuses on the antibacterial, antifungal, and antiviral potential of nanoparticles with their probable mechanism of action.

Synthesis of iron oxide nanoparticles by the recently developed green approach is extremely promising because of its non-toxicity and environmentally friendly behavior. In this study, nano scaled iron oxide particles (α-Fe2O3) were synthesized from hexahydrate ferric chloride (FeCl3.6H2O) with the addition of papaya (Carica papaya) leaf extract under atmospheric conditions. The synthesis of iron oxide nanoparticles was confirmed by systematic characterization using FTIR, XRD, FESEM, EDX and TGA studies. The removal efficiency of remazol yellow RR dye with the synthesized iron oxide nanoparticles as a photocatalyst was determined along with emphasizing on the parameters of catalyst dosage, initial dye concentration and pH. Increasing the dose of iron oxide nanoparticles enhanced the decolorization of the dyes and a maximum 76.6% dye degradation was occurred at pH 2 after 6 h at a catalyst dose of 0.8 g/L. Unit removal capacity of the photocatalyst was found to be 340 mg/g at dye concentration of 70 ppm and at a catalyst dose of 0.4 g/L. The synthesized nanoparticles showed moderate antibacterial activity against Klebsiella spp., E.Coli, Pseudomonas spp., S.aureus bacterial strains. Although the cytotoxic effect of nanoparticles against Hela, BHK-21 and Vero cell line was found to be toxic at maximum doses but it can be considered for tumor cell damage because it showed excellent activity against the Hela and BHK-21 cell lines.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of the ongoing pandemic of coronavirus disease 2019 (COVID-19), a public health emergency of international concerns declared by the World Health Organization (WHO). An immuno-informatics approach along with comparative genomics was applied to design a multi-epitope-based peptide vaccine against SARS-CoV-2 combining the antigenic epitopes of the S, M, and E proteins. The tertiary structure was predicted, refined and validated using advanced bioinformatics tools. The candidate vaccine showed an average of ≥90.0% world population coverage for different ethnic groups. Molecular docking and dynamics simulation of the chimeric vaccine with the immune receptors (TLR3 and TLR4) predicted efficient binding. Immune simulation predicted significant primary immune response with increased IgM and secondary immune response with high levels of both IgG1 and IgG2. It also increased the proliferation of T-helper cells and cytotoxic T-cells along with the increased IFN-γ and IL-2 cytokines. The codon optimization and mRNA secondary structure prediction revealed that the chimera is suitable for high-level expression and cloning. Overall, the constructed recombinant chimeric vaccine candidate demonstrated significant potential and can be considered for clinical validation to fight against this global threat, COVID-19.

Introduction. Effective sanitation strategies for poultry farms require an appropriate selection of the disinfectant based on the contaminants present and their sensitivity to the disinfectants. Aim. The current study investigated the prevalence of streptococci/micrococci in poultry farms of Bangladesh and the efficacy of commercial disinfectants (Savlon, Lysol, Quatovet, Virkon S, and Virocid) along with alcohol against these pathogens to adopt appropriate strategies. Materials and Methods. Conventional approaches and the 16S rRNA gene sequencing were performed to confirm the isolates at the species level along with microtiter biofilm assay to determine their biofilm-forming ability. Efficacy of the disinfectants was tested against those isolates using agar well diffusion and minimum inhibitory concentration (MIC) test by broth dilution method using different dilutions of the disinfectants. Results. Staphylococcus lentus (n = 32), Micrococcus luteus (n = 7), and Micrococcus aloeverae (n = 4) were confirmed among 102 presumptively screened streptococci/micrococci isolates from 43 samples. No single disinfectant showed equally high efficacy against all three bacterial species in agar well diffusion test, although Virocid showed the lowest MIC against all three of them. Lysol was least effective among the commercial disinfectants by both MIC and diffusion method, although each commercial disinfectant was more effective than alcohol. Considering both the average diameter of the inhibition zones and the MIC values, efficacy can be interpreted as Virocid > Quatovet > Savlon > Virkon S > Lysol. Although the efficacy decreased with decreasing concentration, the disinfectants retained a satisfactory level of efficacy at 50% concentration. Among test pathogens, M. aloeverae was the most sensitive to the disinfectants and the weakest biofilm producers, whereas 4/14 S. lentus and 1/5 M. luteus were strong biofilm producers, which may cause more reduction in the efficacy in environmental conditions. Conclusion. As no ideal disinfectant was found in the study, the efficacy of the disinfectants should be routinely evaluated and validated to ensure the sanitation standards in the poultry sector.

Abstract Background Salmonella spp. is one of the most common pathogens associated with fresh produce related foodborne illness. This study aimed to determine Salmonella spp. contamination level in betel leaf, internalization potential and possible decontamination process. Results A total of 77% betel leaf sample collected from local market was found to be contaminated with Salmonella spp. Of all the Salmonella spp. isolated and identified, 28.5% belong to Salmonella enterica subsp. enterica serovar Enteritidis, 19.5% belong to Salmonella Typhimurium, 15.6% to Salmonella Paratyphi, 10.4% to Salmonella Schottmuelleri, 9.1% to Salmonella Gallinarum, 10.4% to Salmonella Choleraesuis and 6.5% belong to Salmonella Bongori. Internalized Salmonella spp. showed moderate resistance to commonly used antibiotics. Treatment with common surface food disinfectants could not remove Salmonella spp. completely from betel leaf indicating the possibility that the bacteria may be in internal tissue of the leaf. Assessment of internalization potential showed that Salmonella spp. isolated from inner part of betel leaf pose better internalization potential (6.7–7.4 logCFU/gm) comparing with ATCC (American Type Culture Collection) strains (0.86–0.6 logCFU/gm). The isolates also showed better survivability in internalized condition, biofilm formation ability and motility than ATCC strains. Prevalence and expression of invasion (sefA and invA) and type 3 secretion system (TTSS) associated genes (hila, avrA and sopE) were high in internalized Salmonella isolates. Commercial disinfectants as well as H2O2 were found to have poor efficacy (log reduction around 2 CFU/gm) against internalized Salmonella. Ozonated water showed better decontamination efficiency (log reduction around 3 CFU/gm) whereas ethanolic extract of Terminalia arjuna stem bark showed higher decontamination (log reduction around 4.5 CFU/gm) of internalized Salmonella. Conclusion Salmonella spp. can ingress into betel leaf and better decontamination treatment is needed to be established.

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.