Exploring the Efficacy of Peptides and Mimics against Influenza A Virus, Adenovirus, and Murine Norovirus.

The ongoing battle against viral pandemics continues, with the possibility of future outbreaks. The search for effective antiviral compounds that can combat a diverse range of viruses continues to be a focal point of research. This study investigated the efficacy of two natural antimicrobial peptides (AMPs) (lactoferricin and LL-37), two synthetic AMPs (melimine and Mel4), and nine AMP mimics (758, 1091, 1096, 1083, 610, NAPL, 3-BIPL, 4-BIPL, and Sau-22) against influenza A virus strains H1N1 and H3N2, human adenovirus 5 (HAdV-5), and murine norovirus 1 (MNV-1). These compounds were tested using virus pre-treatment, cell pre-treatment, or post-cell entry treatment assays, electron microscopy, and circular dichroism (CD), alongside evaluations of cytotoxicity against the host cells. After virus pre-treatment, the AMP mimics 610 and Sau-22 had relatively low IC50 values for influenza strains H1N1 (2.35 and 6.93 µM, respectively) and H3N2 (3.7 and 5.34 µM, respectively). Conversely, natural and synthetic AMPs were not active against these strains. For the non-enveloped viruses, the AMP Mel4 and mimic 1083 had moderate activity against HAdV-5 (Mel4 IC50 = 47.4 µM; 1083 IC50 = 47.2 µM), whereas all AMPs, but none of the mimics, were active against norovirus (LL-37 IC50 = 4.2 µM; lactoferricin IC50 = 23.18 µM; melimine IC50 = 4.8 µM; Mel4 IC50 = 8.6 µM). Transmission electron microscopy demonstrated that the mimics targeted the outer envelope of influenza viruses, while the AMPs targeted the capsid of non-enveloped viruses. CD showed that Mel4 adopted an α-helical structure in a membrane mimetic environment, but mimic 758 remained unstructured. The diverse activity against different virus groups is probably influenced by charge, hydrophobicity, size, and, in the case of natural and synthetic AMPs, their secondary structure. These findings underscore the potential of peptides and mimics as promising candidates for antiviral therapeutics against both enveloped and non-enveloped viruses.

C-C Chemokine receptor-like 2 (CCRL2) acts as coreceptor for human immunodeficiency virus-2.

INTRODUCTION: Most of the typical chemokine receptors (CKRs) have been identified as coreceptors for a variety of human and simian immunodeficiency viruses (HIVs and SIVs). This study evaluated CCRL2 to examine if it was an HIV/SIV coreceptor. METHODS: The Human glioma cell line, NP-2, is normally resistant to infection by HIV and SIV. The cell was transduced with amplified cluster of differentiation 4 (CD4) as a receptor and CCR5, CXCR4 and CCRL2 as coreceptor candidates to produce NP-2/CD4/coreceptor cells (). The cells were infected with multiplicity of infection (MOI) 1.0. Infected cells were detected by indirect immunofluorescence assay (IFA). Multinucleated giant cells (MGC) in syncytia were quantified by Giemsa staining. Proviral DNA was detected by polymerase chain reaction (PCR), and reverse transcriptase (RT) activity was measured. RESULTS: IFA detected viral antigens of the primary isolates, HIV-1HAN2 and HIV-2MIR in infected NP-2/CD4/CCRL2 cells, indicated CCRL2 as a functional coreceptor. IFA results were confirmed by the detection of proviral DNA and measurement of RT-activity in the spent cell supernatants. Additionally, MGC was detected in HIV-2MIR-infected NP-2/CD4/CCCRL2 cells. HIV-2MIR were found more potent users of CCRL2 than HIV-1HAN2. Moreover, GWAS studies, gene ontology and cell signaling pathways of the HIV-associated genes show interaction of CCRL2 with HIV/SIV envelope protein. CONCLUSIONS: In vitro experiments showed CCRL2 to function as a newly identified coreceptor for primary HIV-2 isolates conveniently. The findings contribute additional insights into HIV/SIV transmission and pathogenesis. However, its in vivo relevance still needs to be evaluated. Confirming in vivo relevance, ligands of CCRL2 can be investigated as potential targets for HIV entry-inhibitor drugs.

Mobile Colistin-Resistant Genes mcr-1, mcr-2, and mcr-3 Identified in Diarrheal Pathogens among Infants, Children, and Adults in Bangladesh: Implications for the Future.

Colistin is a last-resort antimicrobial for treating multidrug-resistant Gram-negative bacteria. Phenotypic colistin resistance is highly associated with plasmid-mediated mobile colistin resistance (mcr) genes. mcr-bearing Enterobacteriaceae have been detected in many countries, with the emergence of colistin-resistant pathogens a global concern. This study assessed the distribution of mcr-1, mcr-2, mcr-3, mcr-4, and mcr-5 genes with phenotypic colistin resistance in isolates from diarrheal infants and children in Bangladesh. Bacteria were identified using the API-20E biochemical panel and 16s rDNA gene sequencing. Polymerase chain reactions detected mcr gene variants in the isolates. Their susceptibilities to colistin were determined by agar dilution and E-test by minimal inhibitory concentration (MIC) measurements. Over 31.6% (71/225) of isolates showed colistin resistance according to agar dilution assessment (MIC > 2 µg/mL). Overall, 15.5% of isolates carried mcr genes (7, mcr-1; 17, mcr-2; 13, and mcr-3, with co-occurrence occurring in two isolates). Clinical breakout MIC values (≥4 µg/mL) were associated with 91.3% of mcr-positive isolates. The mcr-positive pathogens included twenty Escherichia spp., five Shigella flexneri, five Citrobacter spp., two Klebsiella pneumoniae, and three Pseudomonas parafulva. The mcr-genes appeared to be significantly associated with phenotypic colistin resistance phenomena (p = 0.000), with 100% colistin-resistant isolates showing MDR phenomena. The age and sex of patients showed no significant association with detected mcr variants. Overall, mcr-associated colistin-resistant bacteria have emerged in Bangladesh, which warrants further research to determine their spread and instigate activities to reduce resistance.

A review of the antiviral activity of cationic antimicrobial peptides.

Viral epidemics are occurring frequently, and the COVID-19 viral pandemic has resulted in at least 6.5 million deaths worldwide. Although antiviral therapeutics are available, these may not have sufficient effect. The emergence of resistant or novel viruses requires new therapies. Cationic antimicrobial peptides are agents of the innate immune system that may offer a promising solution to viral infections. These peptides are gaining attention as possible therapies for viral infections or for use as prophylactic agents to prevent viral spread. This narrative review examines antiviral peptides, their structural features, and mechanism of activity. A total of 156 cationic antiviral peptides were examined for information of their mechanism of action against both enveloped and non-enveloped viruses. Antiviral peptides can be isolated from various natural sources or can be generated synthetically. The latter tend to be more specific and effective and can be made to have a broad spectrum of activity with minimal side effects. Their unique properties of being positively charged and amphipathic enable their main mode of action which is to target and disrupt viral lipid envelopes, thereby inhibiting viral entry and replication. This review offers a comprehensive summary of the current understanding of antiviral peptides, which could potentially aid in the design and creation of novel antiviral medications.

Antiviral Activity of Anthranilamide Peptidomimetics against Herpes Simplex Virus 1 and a Coronavirus.

The development of potent antiviral agents is of utmost importance to combat the global burden of viral infections. Traditional antiviral drug development involves targeting specific viral proteins, which may lead to the emergence of resistant strains. To explore alternative strategies, we investigated the antiviral potential of antimicrobial peptidomimetic compounds. In this study, we evaluated the antiviral potential of 17 short anthranilamide-based peptidomimetic compounds against two viruses: Murine hepatitis virus 1 (MHV-1) which is a surrogate of human coronaviruses and herpes simplex virus 1 (HSV-1). The half-maximal inhibitory concentration (IC50) values of these compounds were determined in vitro to assess their potency as antiviral agents. Compounds 11 and 14 displayed the most potent inhibitory effects with IC50 values of 2.38 µM, and 6.3 µM against MHV-1 while compounds 9 and 14 showed IC50 values of 14.8 µM and 13 µM against HSV-1. Multiple antiviral assessments and microscopic images obtained through transmission electron microscopy (TEM) collectively demonstrated that these compounds exert a direct influence on the viral envelope. Based on this outcome, it can be concluded that peptidomimetic compounds could offer a new approach for the development of potent antiviral agents.

Detection of mobile colistin-resistance gene variants (mcr-1 and mcr-2) in urinary tract pathogens in Bangladesh: the last resort of infectious disease management colistin efficacy is under threat.

Background: Currently, colistin-resistant pathogens emerged has become a global health concern. This study assessed the distribution of mcr-1 to mcr-5 variants with the phenotypic colistin-resistance in bacterial isolates from urinary tract infection (UTI) patients in Bangladesh.Methods: A cross-sectional study was conducted between April 2017 and March 2018 to enroll uncomplicated UTI patients, and 142 urine samples were analyzed. Uropathogens were identified using the API-20E biochemical panel and 16s rRNA gene sequencing. Polymerase chain reactions detected the mcr gene variants in the UTI isolates. The phenotypic colistin-susceptibility was determined by the Kirby-Bauer disc-diffusion method and the minimal inhibitory concentration (MIC) measurement.Results: The combined carriage of mcr-1 and mcr-2 genes in 11.4% (14/123) of urinary tract pathogens. The mcr-positive pathogens include five Escherichia coli, three Klebsiella pneumoniae, three Pseudomonas putida, two Enterobacter cloacae, and one Enterobacter hormaechei. The mcr-positive variant showed significantly higher phenotypic colistin resistance with MIC between >16 µg/mL and >128 µg/mL (p< 0.001). Over 85% of colistin-resistant isolates showed MDR phenomena.Conclusions: The emergence of the clinical MDR pathogens with resistance to a highly selective drug may lead to a lack of treatment options for the infectious diseases and spread of infection to the unaffected cohorts.

Ongoing efforts to improve the management of patients with diabetes in Bangladesh and the implications.

BACKGROUND: Prevalence rates of patients with diabetes are growing across countries, and Bangladesh is no exception. Associated costs are also increasing, driven by costs associated with the complications of diabetes including hypoglycemia. Long-acting insulin analogues were developed to reduce hypoglycemia as well as improve patient comfort and adherence. However, they have been appreciably more expensive, reducing their affordability and use. Biosimilars offer a way forward. Consequently, there is a need to document current prescribing and dispensing rates for long-acting insulin analogues across Bangladesh, including current prices and differences, as a result of affordability and other issues. METHODS: Mixed method approach including surveying prescribing practices in hospitals coupled with dispensing practices and prices among community pharmacies and drug stores across Bangladesh. This method was adopted since public hospitals only dispense insulins such as soluble insulins free-of-charge until funds run out and all long-acting insulin analogues have to be purchased from community stores. RESULTS: There has been growing prescribing and dispensing of long-acting insulins in Bangladesh in recent years, now accounting for over 80% of all insulins dispensed in a minority of stores. This increase has been helped by growing prescribing and dispensing of biosimilar insulin glargine at lower costs than the originator, with this trend likely to continue with envisaged growth in the number of patients. Consequently, Bangladesh can serve as an exemplar to other low- and middle-income countries struggling to fund long-acting insulin analogues for their patients. CONCLUSIONS: It was encouraging to see continued growth in the prescribing and dispensing of long-acting insulin analogues in Bangladesh via the increasing availability of biosimilars. This is likely to continue benefitting all key stakeholder groups.

Disproportionate COVID-19 vaccine acceptance rate among healthcare professionals on the eve of nationwide vaccine distribution in Bangladesh.

BACKGROUND: Acceptance of the COVID-19 vaccine by the target groups would play a crucial role in stemming the pandemic. Healthcare professionals (HCPs) are the priority group for vaccination due to them having the highest risk of exposure to infection. This survey aimed to assess their acceptance of COVID-19 vaccines in Bangladesh. RESEARCH DESIGN AND METHODS: A cross-sectional survey using an online questionnaire was conducted between January 3 to 25, 2021, among HCPs (n = 834) in Bangladesh. RESULTS: Less than 50% of HCPs would receive the vaccine against COVID-19 if available and 54% were willing to take the vaccine at some stage in the future. Female participants (OR:1.64;95%CI:1.172-2.297), respondents between 18-34 years old (OR:2.42; 95% CI:1.314-4.463), HCPs in the public sector (OR:2.09; 95% CI:1.521-2.878), and those who did not receive a flu vaccine in the previous year (OR:3.1; 95% CI:1.552-6.001) were more likely to delay vaccination. CONCLUSIONS: The study revealed that, if available, less than half of the HCPs would accept a COVID-19 vaccine in Bangladesh. To ensure the broader success of the vaccination drive, tailored strategies and vaccine promotion campaigns targeting HCPs and the general population are needed.

High abundance of the colistin resistance gene mcr-1 in chicken gut-bacteria in Bangladesh.

Colistin is considered a last-resort reserved drug for the treatment of critical human infections by Gram-negative bacteria. Phenotypic colistin-resistance is strongly associated with plasmid-mediated mobile colistin resistance (mcr) genes. The mcr-bearing Enterobacteriaceae have been detected in many countries from environments, animals, and humans. This study investigated phenotypic colistin-resistance and the distribution of mcr-1, mcr-2, mcr-3, mcr-4, and mcr-5 genes in chicken-gut bacteria in Bangladesh. Bacteria were isolated from poultry- and native-chicken droppings, and their susceptibilities to colistin were determined by agar dilution and E-test minimal inhibitory concentration (MIC) measurements. Multiplex polymerase chain reactions detected mcr-1 to mcr-5 genes. Overall, 61.7% (92/149) of the isolates showed colistin resistance by agar dilution assessment (MIC > 2.0 µg/mL). The phenotypic resistance was observed considerably higher in poultry-chicken isolates (64.6%, 64/99) than in native-chicken isolates (56%, 28/50; p = 0.373). All the resistant isolates showed MIC levels between > 2 and > 128 µg/mL. The mcr-genes (mcr-1and mcr-2 combined) were detected more in poultry gut bacteria (36.4%) than native-chicken isolates (20%, p = 0.06). Despite bacteria sources, mcr-genes appeared to be significantly associated with phenotypic colistin-resistance phenomena (p < 0.001). Prior colistin usage led to a substantial increase in the proportion of bacteria with mcr-genes and phenotypic resistance (p < 0.001).

Genotypic to Phenotypic Resistance Discrepancies Identified Involving ß-Lactamase Genes, blaKPC, blaIMP, blaNDM-1, and blaVIM in Uropathogenic Klebsiella pneumoniae.

INTRODUCTION: Klebsiella pneumoniae carbapenemase (KPC) belongs to the Group-A ß-lactamases that incorporate serine at their active site and hydrolyze various penicillins, cephalosporins, and carbapenems. Metallo-beta-lactamases (MBLs) are group-B enzymes that contain one or two essential zinc ions in the active sites and hydrolyze almost all clinically available ß-lactam antibiotics. Klebsiella pneumoniae remains the pathogen with the most antimicrobial resistance to KPC and MBLs. METHODS: This research investigated the blaKPC, and MBL genes, namely, blaIMP, blaVIM, and blaNDM-1 and their phenotypic resistance to K. pneumoniae isolated from urinary tract infections (UTI) in Bangladesh. Isolated UTI K. pneumoniae were identified by API-20E and 16s rDNA gene analysis. Their phenotypic antimicrobial resistance was examined by the Kirby-Bauer disc diffusion method, followed by minimal inhibitory concentration (MIC) determination. blaKPC, blaIMP, blaNDM-1, and blaVIM genes were evaluated by polymerase chain reactions (PCR) and confirmed by sequencing. RESULTS: Fifty-eight K. pneumoniae were identified from 142 acute UTI cases. Their phenotypic resistance to amoxycillin-clavulanic acid, cephalexin, cefuroxime, ceftriaxone, and imipenem were 98.3%, 100%, 96.5%, 91.4%, 75.1%, respectively. Over half (31/58) of the isolates contained either blaKPC or one of the MBL genes. Individual prevalence of blaKPC, blaIMP, blaNDM-1, and blaVIM were 15.5% (9), 10.3% (6), 22.4% (13), and 19% (11), respectively. Of these, eight isolates (25.8%, 8/31) were found to have two genes in four different combinations. The co-existence of the ESBL genes generated more resistance than each one individually. Some isolates appeared phenotypically susceptible to imipenem in the presence of blaKPC, blaIMP, blaVIM, and blaNDM-1 genes, singly or in combination. CONCLUSION: The discrepancy of genotype and phenotype resistance has significant consequences for clinical bacteriology, precision in diagnosis, the prudent selection of antimicrobials, and rational prescribing. Heterogeneous phenotypes of antimicrobial susceptibility testing should be taken seriously to avoid inappropriate diagnostic and therapeutic decisions.

Rapid Assessment of Price Instability and Paucity of Medicines and Protection for COVID-19 Across Asia: Findings and Public Health Implications for the Future.

Background: Countries have introduced a variety of measures to prevent and treat COVID-19 with medicines and personal protective equipment (PPE), with some countries adopting preventative strategies earlier than others. However, there has been considerable controversy surrounding some treatments. This includes hydroxychloroquine where the initial hype and misinformation lead to shortages, price rises and suicides. Price rises and shortages have also been seen for PPE. Such activities can have catastrophic effects on patients where there are high co-payment levels and issues of affordability. Consequently, there is a need to investigate this further. Objective: Assess changes in the availability, utilization and prices of relevant medicines and PPE during the pandemic among a range of Asian countries. Our approach: Narrative literature review combined with interviews among community pharmacists to assess changes in consumption, prices and shortages of medicines and PPE from the beginning of March 2020 until end of May 2020. In addition, suggestions on ways to reduce misinformation. Results: 308 pharmacists took part from five Asian countries. There was an appreciable increase in the utilization of antimicrobials in Pakistan (in over 88% of pharmacies), with lower increases or no change in Bangladesh, India, Malaysia and Vietnam. Encouragingly, there was increased use of vitamins/immune boosters and PPE across the countries, as well as limited price rises for antimicrobials in India, Malaysia and Vietnam, although greater price rises seen for analgesics and vitamin C/immune boosters. Appreciable price increases were also seen for PPE across some countries. Conclusion: Encouraging to see increases in utilization of vitamins/immune boosters and PPE. However, increases in the utilization and prices of antimicrobials is a concern that needs addressing alongside misinformation and any unintended consequences from the pandemic. Community pharmacists can play a key role in providing evidence-based advice, helping to moderate prices, as well as helping address some of the unintended consequences of the pandemic.

Type-2 Diabetes Mellitus Individuals Carry Different Periodontal Bacteria

ABSTRACT Objective: To identify etiologic microbiota associated periodontal diseases among diabetes patients and the factors related to the most commonly identified bacteria species. Material and Methods: Periodontal plaque samples from 11 diabetic participants and 13 non-diabetic controls were collected to assess their aerobic and anaerobic bacterial growth. Different distinct colonies were identified by microscopic and 16srDNA sequencing. Pearson's chi-square tests were conducted to examine any association between categorical variables. Results: The diabetic subjects revealed a more intense plaque formation with a mean plaque index of 2.4 compared to 1.8 in non-diabetics. A total of 86 bacteria were isolated from 24 plaque samples, 44 were aerobic, and 42 were anaerobic. Only aerobic isolates, 22 from diabetic patients and 22 from non-diabetic patients, were evaluated in these analyses. Bacillus spp. (B. cereus mainly) and Klebsiella spp. (K. pneumoniae, K. aerogenes, K. oxytoca) were detected markedly higher in non-diabetic individuals than in diabetic subjects (p=0.026 and p=0.021, respectively). Some bacteria were only identified in the dental plaque of diabetic individuals, namely, Bacillus mojavensis, Enterobacter cloacae, Proteus mirabilis, Staphylococcus epidermidis, Staphylococcus hominis, Staphylococcus pasteuri, Streptococcus mutans, and Streptococcus pasteurianus. The presence of acid reflux and jaundice were significantly associated with the most common bacterial isolate, namely Bacillus spp., with the p-values of 0.007 and 0.001, respectively. Conclusion: Type-2 diabetes mellitus is associated with a higher amount of dental plaques. Periodontal plaque samples from diabetic and non-diabetic subjects possess differential microbial communities. Diabetic plaques contain more versatile microbes predominated by gram-positive streptococci and staphylococci.