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1.
Int J Mol Sci ; 25(13)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-39000138

RESUMEN

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.


Asunto(s)
Antivirales , Norovirus , Norovirus/efectos de los fármacos , Animales , Humanos , Ratones , Antivirales/farmacología , Antivirales/química , Virus de la Influenza A/efectos de los fármacos , Virus de la Influenza A/fisiología , Péptidos Antimicrobianos/farmacología , Péptidos Antimicrobianos/química , Subtipo H3N2 del Virus de la Influenza A/efectos de los fármacos , Perros , Adenoviridae/efectos de los fármacos , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Células de Riñón Canino Madin Darby , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/química
2.
Brief Bioinform ; 22(4)2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-33253374

RESUMEN

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.


Asunto(s)
Infecciones por VIH/metabolismo , VIH-2/metabolismo , Receptores CCR/metabolismo , Infecciones por VIH/genética , VIH-1/genética , VIH-1/metabolismo , VIH-2/genética , Humanos , Células Jurkat , Receptores CCR/genética
3.
Brief Bioinform ; 22(2): 1387-1401, 2021 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-33458761

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infected individuals that have hypertension or cardiovascular comorbidities have an elevated risk of serious coronavirus disease 2019 (COVID-19) disease and high rates of mortality but how COVID-$19$ and cardiovascular diseases interact are unclear. We therefore sought to identify novel mechanisms of interaction by identifying genes with altered expression in SARS-CoV-$2$ infection that are relevant to the pathogenesis of cardiovascular disease and hypertension. Some recent research shows the SARS-CoV-$2$ uses the angiotensin converting enzyme-$2$ (ACE-$2$) as a receptor to infect human susceptible cells. The ACE2 gene is expressed in many human tissues, including intestine, testis, kidneys, heart and lungs. ACE2 usually converts Angiotensin I in the renin-angiotensin-aldosterone system to Angiotensin II, which affects blood pressure levels. ACE inhibitors prescribed for cardiovascular disease and hypertension may increase the levels of ACE-$2$, although there are claims that such medications actually reduce lung injury caused by COVID-$19$. We employed bioinformatics and systematic approaches to identify such genetic links, using messenger RNA data peripheral blood cells from COVID-$19$ patients and compared them with blood samples from patients with either chronic heart failure disease or hypertensive diseases. We have also considered the immune response genes with elevated expression in COVID-$19$ to those active in cardiovascular diseases and hypertension. Differentially expressed genes (DEGs) common to COVID-$19$ and chronic heart failure, and common to COVID-$19$ and hypertension, were identified; the involvement of these common genes in the signalling pathways and ontologies studied. COVID-$19$ does not share a large number of differentially expressed genes with the conditions under consideration. However, those that were identified included genes playing roles in T cell functions, toll-like receptor pathways, cytokines, chemokines, cell stress, type 2 diabetes and gastric cancer. We also identified protein-protein interactions, gene regulatory networks and suggested drug and chemical compound interactions using the differentially expressed genes. The result of this study may help in identifying significant targets of treatment that can combat the ongoing pandemic due to SARS-CoV-$2$ infection.


Asunto(s)
COVID-19/complicaciones , Enfermedades Cardiovasculares/complicaciones , Biología Computacional , Hipertensión/complicaciones , Biología de Sistemas , COVID-19/virología , Humanos , SARS-CoV-2/aislamiento & purificación
4.
BMC Psychiatry ; 21(1): 271, 2021 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-34034679

RESUMEN

BACKGROUND: Healthcare workers (HCWs) who are in the frontline during the COVID-19 pandemic are often under significant pressures that may predispose them to symptoms of poor mental health. This study aimed to investigate the prevalence of anxiety and depression among HCWs and factors correlated with mental health concerns during the COVID-19 pandemic in Bangladesh. And, it also aimed to evaluate the psychometric properties of the Bangla version of the Hospital Anxiety and Depression Scale (HADS). METHODS: A cross-sectional survey was conducted between July and August, 2020. A self-reported online questionnaire was utilized to collect data. The survey included questions concerning socio-demographic, lifestyle, and work setting, as well as the HADS. A confirmatory factor analysis (CFA) and multiple linear regression analysis were performed. RESULTS: Data from 803 HCWs (50.7% male; mean age: 27.3 [SD = 6.9]; age range: 18-58 years) were included in the final analysis. The Bangla HADS was psychometrically sound, and demonstrated good internal consistency and reliability (α = 0.83), and excellent construct validity. Prevalence estimates of anxiety and depression were 69.5%, and 39.5%, respectively, for less severe symptomology (at least borderline abnormal), and 41.2% and 15.7% for more severe (at least abnormal) symptomology. Regression analyses with the total HADS score as a dependent variable revealed significant (p < 0.05) associations with female gender, moderate and poor health status, infrequent physical exercising, smoking, having had regrets about one's profession because of the pandemic and associated experiences, not updating on the latest COVID-19-related research, experiencing discrimination in the workplace, and facing social problems due to working in a lab or hospital during the COVID-19 pandemic. CONCLUSIONS: Symptoms of anxiety and depression are prevalent among HCWs during the COVID-19 pandemic in Bangladesh. The findings suggest a need for screening for mental health concerns, and employing early intervention to help these individuals.


Asunto(s)
COVID-19 , Pandemias , Adolescente , Adulto , Ansiedad/epidemiología , Bangladesh/epidemiología , Estudios Transversales , Depresión/epidemiología , Femenino , Personal de Salud , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Reproducibilidad de los Resultados , SARS-CoV-2 , Adulto Joven
5.
Harm Reduct J ; 16(1): 38, 2019 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-31208419

RESUMEN

BACKGROUND: Bacterial infection is a major cause of morbidity and mortality for persons who inject drugs (PWID). Injection cessation may help abrogate such infections, but maintaining complete cessation is challenging. Limited data exists on the role of reduced injection intensity on invasive bacterial infection risk. We sought to evaluate decreased risk for bacterial infections following cessation and substantive reduction in the injection intensity. METHODS: Participants were persons in the AIDS Linked to the Intravenous Experience (ALIVE) cohort with initial high-frequency injection drug use (> 1 daily). Pooled logistic regression with generalized estimating equations was used to estimate risk for invasive bacterial infection (pneumonia, endocarditis, or sepsis) among participants achieving complete injection cessation or reduced injection intensity relative to those with sustained high-frequency use. RESULTS: Of 2247 study participants with 12,469 paired study visits, complete injection cessation was achieved at 13.5% and reduced injection intensity at 25.5% of study visits. Adjusting for sociodemographics and HIV status, injection cessation was associated with a 54% reduction of bacterial infection at 3 months (odds ratio [OR] 0.46, 95% CI 0.25-0.84) and a 46% reduction at 6 months (OR 0.54, 95% CI 0.36-0.81). Reduced injection intensity was associated with a 36% reduction of infection at 3 months (OR 0.64, 95% CI 0.43-0.96) and a 26% reduction at 6 months (OR 0.74, 95% CI 0.56-0.98). CONCLUSIONS: Both complete cessation and reduced injection frequency demonstrate substantial benefit in reducing invasive bacterial infection risk among PWID. With high rates of relapse into injection use, targeting sustained reductions in drug use intensity may be a key harm reduction modality for improving clinical outcomes in this population.


Asunto(s)
Endocarditis Bacteriana/epidemiología , Inyecciones Intravenosas/estadística & datos numéricos , Neumonía Bacteriana/epidemiología , Sepsis/epidemiología , Abuso de Sustancias por Vía Intravenosa/epidemiología , Adulto , Factores de Edad , Alcoholismo , Infecciones Bacterianas/epidemiología , Fumar Cigarrillos/epidemiología , Trastornos Relacionados con Cocaína/epidemiología , Femenino , Infecciones por VIH/epidemiología , Reducción del Daño , Dependencia de Heroína/epidemiología , Humanos , Modelos Logísticos , Masculino , Factores Sexuales , Estados Unidos/epidemiología
6.
BMC Infect Dis ; 14: 354, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24980635

RESUMEN

BACKGROUND: The chemokine receptors (CKRs), mainly CCR5 and CXCR4 function as major coreceptors in infections caused by human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV). Approximately 20 G protein-coupled receptors (GPCRs) have been identified as minor coreceptors, alike CCR6 that we reported recently. Since CKR-L3 is indentified as a natural isoform of CCR6, we attempted in this study to explore the coreceptor function of CKR-L3. METHODS: NP-2 cells transduced with CD4-receptor (NP-2/CD4) normally remain resistant to HIV or SIV infection. However, the introduction of functional coreceptors can make these cells susceptible to these viruses. NP-2/CD4/CKR-L3 cells were produced to examine the coreceptor activity of CKR-L3. Likely, CCR6-isoform and the major coreceptors, CCR5 and CXCR4 were also examined in parallel. Presence of viral antigen in infected NP-2/CD4/coreceptor cells was detected by indirect immunofluorescence assay (IFA). The results were validated by detection of syncytia, proviral DNA and by measuring reverse transcriptase (RT) activities. RESULTS: HIV-2MIR and SIVsmE660 were found to infect NP-2/CD4/CKR-L3 cells, indicative of the coreceptor function of CKR-L3. Viral antigens appeared faster in NP-2/CD4/CKR-L3 cells than in NP-2/CD4/CCR6, indicating that CKR-L3 is a more efficient coreceptor. Moreover, syncytia formation was more rapid and RT release evidenced earlier and at higher levels with CKR-L3 than with CCR6. Sequence analysis in the C2-V3 envelope region of HIV-2MIR replicated through CKR-L3 and CCR6 coreceptor showed two and three amino acid substitutions respectively, in the C2 region compared to the CCR5-variant. The SIVsmE660-CKRL3 variant showed three amino acid substitutions in the V1 region, one change in the V2 and two changes in the C2 region. The SIVsmE660-CCR6 variant produced two changes in the V1 region, and three in the C2 region. CONCLUSIONS: Isoform CKR-L3 exhibited coreceptor activity for limited primary HIV and SIV isolates with better efficiency than the parent CCR6-isoform. Amino acid substitutions in the envelope region of these viruses may confer selective pressure towards CKR-L3-use. CKR-L3 with other minor coreceptors may contribute to HIV and SIV pathogenesis including dissemination, trafficking and latency especially when major coreceptors become compromised. However, further works will be required to determine its clinical significance in HIV and SIV infection.


Asunto(s)
VIH/fisiología , Receptores CCR6/metabolismo , Receptores del VIH/metabolismo , Virus de la Inmunodeficiencia de los Simios/fisiología , Animales , Línea Celular , Humanos , Datos de Secuencia Molecular , Eliminación de Secuencia , Replicación Viral
7.
Microorganisms ; 12(8)2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39203431

RESUMEN

Carbapenems are the antibiotics of choice for treating multidrug-resistant bacterial infections. Metallo-ß-lactamases (MBLs) are carbapenemases capable of hydrolyzing nearly all therapeutically available beta-lactam antibiotics. Consequently, this research assessed the distribution of two MBL genes and three ß-lactamases and their associated phenotypic resistance in diarrheal and urinary-tract infections (UTIs) to guide future policies. Samples were collected through a cross-sectional study, and ß-lactamase genes were detected via PCR. A total of 228 diarrheal bacteria were isolated from 240 samples. The most predominant pathogens were Escherichia coli (32%) and Klebsiella spp. (7%). Phenotypic resistance to amoxicillin-clavulanic acid, aztreonam, cefuroxime, cefixime, cefepime, imipenem, meropenem, gentamicin, netilmicin, and amikacin was 50.4%, 65.6%, 66.8%, 80.5%, 54.4%, 41.6%, 25.7%, 41.2%, 37.2%, and 42.9%, respectively. A total of 142 UTI pathogens were identified from 150 urine samples. Klebsiella spp. (39%) and Escherichia coli (24%) were the major pathogens isolated. Phenotypic resistance to amoxicillin-clavulanic acid, aztreonam, cefuroxime, cefixime, cefepime, imipenem, meropenem, gentamicin, netilmicin, and amikacin was 93.7%, 75.0%, 91.5%, 93.7%, 88.0%, 72.5%, 13.6%, 44.4%, 71.1%, and 43%, respectively. Twenty-four diarrheal isolates carried blaNDM-1 or blaVIM genes. The overall MBL gene prevalence was 10.5%. Thirty-six UTI pathogens carried either blaNDM-1 or blaVIM genes (25.4%). Seven isolates carried both blaNDM-1 and blaVIM genes. MBL genes were strongly associated with phenotypic carbapenem and other ß-lactam antibiotic resistance. blaOXA imparted significantly higher phenotypic resistance to ß-lactam antibiotics. Active surveillance and stewardship programs are urgently needed to reduce carbapenem resistance in Bangladesh.

8.
Cureus ; 16(2): e54644, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38389567

RESUMEN

Introduction The emergence of antimicrobial resistance (AMR) is driven by the selection pressure of frequent uses of antimicrobial agents in healthcare, the food chain, agriculture, fishery, and the food animal industry, which poses a serious health risk for transmission-linked humans and the surrounding environment. Livestock, particularly cattle, play an essential role in the food sector in Bangladesh. The food-animal chains can be the potential routes of exposure to AMR-microorganisms for every domain of one health. Antimicrobial resistance genes (ARGs) can impart a reservoir of AMR within the food supply chain, even without pathogenic microorganisms. This study investigated the history of infection for the last six-month period of antimicrobials utilized in cattle farms and the distribution of selected carbapenemase resistance genes, namely, bla-KPC, bla-IMP, bla-VIM, bla-NDM-1, bla-SIM, bla-GIM, bla-SPM, and bla-SME, in cattle feces in Bangladesh. Methods A cross-sectional study was designed to analyze ARGs in fresh cow dung samples collected from commercial farms and individual houses in four Bangladesh districts, namely, Dhaka, Gazipur, Manikganj, and Tangail. Types of cattle breeds, their existing diseases, recent antimicrobial uses, and vaccine uses were recorded. DNA was extracted from each cow dung sample using commercial kits (Qiagen GmbH, Germany). Real-time quantitative polymerase chain reaction (RT-qPCR) was employed to assess the eight carbapenem resistance genes in the extracted DNA. The eight carbapenem resistance genes in the extracted DNA were assessed by RT-qPCR using the qTOWER3 thermal cycler (Analytik Jena GmbH, Konrad-Zuse-Straße 1, 07745 Jena, Germany). Results Group A carbapenemase, bla-KPC, was detected in 66.7% of the samples. However, no bla-SME was identified in all of the test samples. Group B metallo carbapenemase, bla-IMP, bla-NDM-1, bla-VIM, bla-SIM, bla-GIM, and bla-SPM, were in 66.7% (80/120), 49.2% (59/120), 48.3% (58/120), 68.3% (82/120), 58.3% (70/120), and 12.5% (15/120), respectively. Only 8.3% of the tested samples contained no MBL gene; 10% carried a single-type carbapenemase gene; and the remaining 81.7% carried two or more carbapenemase genes concurrently. Co-carriage of four or more genes was found in over 59% of samples. As many as seven genes were found together in 6.7% of samples. ARG detection in commercial cattle samples and household feces is not statistically significant. Conclusions Substantial carbapenem-resistance ARGs were detected in commercially farmed cow dung and household cattle samples. Frequent use of antibiotics for cattle for treatment and prophylactic purposes may influence the high acquisition of ARGs. Bangladeshi cattle farms are reservoirs and routes of AMR, posing a significant threat to the country's public health.

9.
Antibiotics (Basel) ; 13(6)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38927200

RESUMEN

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.

10.
J Virol ; 86(6): 2959-69, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22238310

RESUMEN

Three molecules have been identified as the main cellular factors required for binding and entry of human T-cell leukemia virus type 1 (HTLV-1): glucose transporter 1 (GLUT1), heparan sulfate (HS), and neuropilin 1 (NRP-1). However, the precise mechanism of HTLV-1 cell tropism has yet to be elucidated. Here, we examined the susceptibilities of various human cell lines to HTLV-1 by using vesicular stomatitis virus pseudotypes bearing HTLV-1 envelope proteins. We found that the cellular susceptibility to HTLV-1 infection did not correlate with the expression of GLUT1, HS, or NRP-1 alone. To investigate whether other cellular factors were responsible for HTLV-1 susceptibility, we conducted expression cloning. We identified two HS proteoglycan core proteins, syndecan 1 and syndecan 2, as molecules responsible for susceptibility to HTLV-1. We found that treatment of syndecan 1-transduced cells (expressing increased HS) with heparinase, a heparin-degradative enzyme, reduced HTLV-1 susceptibility without affecting the expression levels of HS chains. To further elucidate these results, we characterized the expression of HS chains in terms of the mass, number, and length of HS in several syndecan 1-transduced cell clones as well as human cell lines. We found a significant correlation between HTLV-1 susceptibility and the number of HS chains with short chain lengths. Our findings suggest that a combination of the number and the length of HS chains containing heparin-like regions is a critical factor which affects the cell tropism of HTLV-1.


Asunto(s)
Infecciones por HTLV-I/virología , Virus Linfotrópico T Tipo 1 Humano/fisiología , Receptores Virales/metabolismo , Sindecano-1/metabolismo , Sindecano-2/metabolismo , Internalización del Virus , Línea Celular Tumoral , Infecciones por HTLV-I/genética , Infecciones por HTLV-I/metabolismo , Virus Linfotrópico T Tipo 1 Humano/genética , Humanos , Neuropilina-1/genética , Neuropilina-1/metabolismo , Receptores Virales/química , Receptores Virales/genética , Sindecano-1/química , Sindecano-1/genética , Sindecano-2/química , Sindecano-2/genética
11.
Microbiol Immunol ; 57(6): 437-44, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23773022

RESUMEN

Human immunodeficiency viruses initiate infections via CCR5 coreceptors and then change their tropism to C-X-C chemokine receptor type 4 (CXCR4), this change being associated with rapid disease progression. HIV-1IIIB, a widely described pure X4-tropic strain, is distinct from R5X4-tropic viruses. In this study, the requirement for amino terminal regions (NTRs) of CXCR4 for entry of HIV-1IIIB virus into host cells was examined and compared to that of R5X4-tropic viruses. CXCR4 and its deletion mutant (CXCR4ΔNTR23; first 23 amino acids removed from NTR) were amplified to examine their coreceptor activities. NP-2/CD4/CXCR4 and NP-2/CD4/CXCR4ΔNTR23 cell lines were prepared accordingly. Indirect immune fluorescence assay (IFA), PCR, and reverse transcriptase (RT) activity were used to compare the process of infection of host cells by HIV-1IIIB virus, one R5-tropic and five other R5X4-tropic viruses. All the R5X4-tropic HIVs were found to utilize both CCR5 and CXCR4 but unable to use CXCR4ΔNTR23 as coreceptors. In contrast, X4-tropic HIV-1IIIB was found to preferentially infect through CXCR4ΔNTR23. Viral antigens in infected NP-2/CD4/CXCR4ΔNTR23 cells were detected by IFA and confirmed by detection of proviral DNA and by performing RT assays on the spent cell-supernatants. In dual tropic viruses, deletion of 23 amino acids from NTR abrogates the coreceptor activity of CXCR4. This observation demonstrates that NTR of CXCR4 have an obligatory coreceptor role for dual tropic viruses. However, HIV-1IIIB may have different requirements for NTR than R5X4 viruses or may infect host cells independent of NTR of CXCR4.


Asunto(s)
VIH/fisiología , Receptores CXCR4/metabolismo , Receptores del VIH/metabolismo , Tropismo Viral , Internalización del Virus , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Reacción en Cadena de la Polimerasa , Receptores CXCR4/genética , Receptores del VIH/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Eliminación de Secuencia
12.
Peptides ; 166: 171024, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37172781

RESUMEN

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.


Asunto(s)
COVID-19 , Virosis , Virus , Humanos , Antivirales/farmacología , Antivirales/uso terapéutico , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/uso terapéutico , Virosis/tratamiento farmacológico
13.
Antibiotics (Basel) ; 12(9)2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37760732

RESUMEN

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.

14.
Mutagenesis ; 27(5): 599-607, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22547343

RESUMEN

It is important to identify the mechanism by which ionising irradiation induces various genomic alterations in the progeny of surviving cells. Ionising irradiation activates mobile elements like retrotransposons, although the mechanism of its phenomena consisting of transcriptions and insertions of the products into new sites of the genome remains unclear. In this study, we analysed the effects of sparsely ionising X-rays and densely ionising carbon-ion beams on the activities of a family of active retrotransposons, long interspersed nuclear elements 1 (L1). We used the L1/reporter knock-in human glioma cell line, NP-2/L1RP-enhanced GFP (EGFP), that harbours full-length L1 tagged with EGFP retrotransposition detection cassette (L1RP-EGFP) in the chromosomal DNA. X-rays and carbon-ion beams similarly increased frequencies the transcription from L1RP-EGFP and its retrotransposition. Short-sized de novo L1RP-EGFP insertions with 5'-truncation were induced by X-rays, while full-length or long-sized insertions (>5 kb, containing ORF1 and ORF2) were found only in cell clones irradiated by the carbon-ion beams. These data suggest that X-rays and carbon-ion beams induce different length of de novo L1 insertions, respectively. Our findings thus highlight the necessity to investigate the mechanisms of mutations caused by transposable elements by ionising irradiation.


Asunto(s)
Elementos de Nucleótido Esparcido Largo/efectos de la radiación , Radiación Ionizante , Animales , Secuencia de Bases , Línea Celular Tumoral , Cromosomas Humanos Par 11/química , Cromosomas Humanos Par 11/genética , Orden Génico , Vectores Genéticos/genética , Humanos , Ratones , Datos de Secuencia Molecular , Mutagénesis Insercional , Mutación/genética , Mutación/efectos de la radiación , Secuencias Repetidas Terminales , Transcripción Genética/efectos de la radiación
15.
Cureus ; 14(3): e23046, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35419241

RESUMEN

In neonates, the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 - COVID-19) is lower. There is the potential for vertical transmission of SARS-CoV-2. To date, only a few reports suggest this possibility. Neonates usually have mild symptoms, but some develop multisystem involvement, which is a concern. COVID-19 infections have been reported both in pregnant women and their neonates. However, the evidence of vertical or horizontal transmission modes has not been fully established. We recorded a case study where a 33-year-old mother was tested positive for COVID-19 infection by RT-PCR during her 27th week of gestation and needed ventilator support for her respiratory distress at that time for 11 days. Subsequently, she gave birth to a female baby at the 35th week via a lower uterine segment cesarean section. The neonate manifested a severe multisystem inflammatory syndrome associated with her possible COVID-19 infection. Sharing her uncommon clinical presentation, immunological syndrome, and disease outcome are noteworthy for similar unforeseen pediatric case management to help guide future investigations and care.

16.
Cureus ; 14(7): e26927, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35865179

RESUMEN

Introduction Gastrointestinal parasitic infections are one of the global health concerns in developing countries like Bangladesh. Among them, Cryptosporidium spp. plays an essential role in causing diarrhea, malnutrition, and poor cognitive function, especially in children. This study was conducted to identify the frequency of Cryptosporidium cases and other parasitic agents.  Methods A cross-sectional observational study was conducted among 219 hospitalized children with diarrhea. The conventional microscopic technique was applied for parasitic detection. Particular staining (modified Ziehl-Neelsen) procedure was performed to identify oocysts of Cryptosporidium spp. A polymerase chain reaction (PCR) was performed to determine the SSU rRNA and gp60 gene of Cryptosporidium.  Results Cysts of Giardia duodenalis (2.3%), ova of Ascaris lumbricoides (1.4%,), Trichuris trichiura (0.5%), and both A. lumbricoides and T. trichiura (0.9%) were identified in samples through wet mount preparation. The distribution of Cryptosporidium spp. as detected by the staining method and nested PCR was 1.4% and 4.1%, respectively.  Conclusion Factors independently associated with Cryptosporidium infection are unsafe water, lack of regular hand washing, and insufficiency of exclusive breastfeeding. This study reports, presumably for the first time, the detection of Cryptosporidium oocysts in Chattogram metropolitan city of Bangladesh.

17.
J Family Med Prim Care ; 11(2): 503-511, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35360769

RESUMEN

Background: COVID-19 pandemic led to increased self-medication of antimicrobials, vitamins, and immune boosters among the common people and consuming without prescription can lead to adverse consequences including antimicrobial resistance. Methods: A cross-sectional study was conducted on community pharmacies in Jodhpur, India. They were inquired regarding the prescription and increased sales (<25%, 25-50%, 50--75%, or 75--100%) of various medicines (Hydroxychloroquine, Azithromycin, Ivermectin, and Vitamin C) during the COVID-19 pandemic. Logistic regression analysis was conducted to assess the relationship between requests for certain COVID-19 medications and an increase in their sale. Results: A total of 204 pharmacies took part, and 88.23% reported patients to approach them without prescriptions. Most of the pharmacies revealed that <25% of patients came without prescription. The majority came for azithromycin (68%) and vitamin C (92%). Increased sales of the four targeted medications were seen by 85.92% of pharmacies compared to last year. A majority (51.5%) reported <25% increased sales of azithromycin, but no change in the sale of hydroxychloroquine and ivermectin. However, 39.6% reported >75% increase in vitamin C sales. Conclusion: There was an increase in the demand for COVID-19 medications without prescription. This study was unable to detect a significant increase in sales of antimicrobials, which is encouraging.

18.
Artículo en Inglés | MEDLINE | ID: mdl-35082135

RESUMEN

INTRODUCTION: Our previous case-control study demonstrated that a high level of intestinal alkaline phosphatase (IAP), an endotoxin-detoxifying anti-inflammatory enzyme secreted by villus-associated enterocytes and excreted with stool, plays a protective role against type 2 diabetes mellitus (T2DM) irrespective of obesity. In the current study, we investigated the long-term effect of IAP deficiency (IAPD) on the pathogenesis of T2DM. RESEARCH DESIGN AND METHODS: A healthy cohort of participants without diabetes (30-60 years old), comprising 188 without IAPD (IAP level: ≥65 U/g stool) and 386 with IAPD (IAP level: <65 U/g stool), were followed up for 5 years. We measured stool IAP (STAP) and fasting plasma glucose, and calculated the risk ratio (RR) using log-binomial regression model. RESULTS: T2DM incidence rates were 8.0%, 11.7%, 25.6%, and 33.3% in participants with 'persistent no IAPD' (IAP level: always ≥65 U/g stool), 'remittent IAPD' (IAP level: increased from <65 U/g stool to ≥65 U/g stool), 'persistent IAPD' (IAP level: always <65 U/g stool), and 'incident IAPD' (IAP level: decreased from ≥65 U/g stool to <65 U/g stool), respectively. Compared with 'persistent no IAPD' the risk of developing T2DM with 'incident IAPD' was 270% higher (RR: 3.69 (95% CI 1.76 to 7.71), χ2 p<0.001). With 'persistent IAPD' the risk was 230% higher (RR: 3.27 (95% CI 1.64 to 6.50), p<0.001). 'Remittent IAPD' showed insignificant risk (RR: 2.24 (95% CI 0.99 to 5.11), p=0.0541). Sensitivity analyses of persistent IAP levels revealed that, compared with participants of the highest persistent IAP pentile (always >115 U/g stool), the rate of increase of fasting glycemia was double and the risk of developing T2DM was 1280% higher (RR: 13.80 (95% CI 1.87 to 101.3), p=0.0099) in participants of the lowest persistent IAP pentile (always <15 U/g stool). A diabetes pathogenesis model is presented. CONCLUSIONS: IAPD increases the risk of developing T2DM, and regular STAP tests would predict individual vulnerability to T2DM. Oral IAP supplementation might prevent T2DM.


Asunto(s)
Fosfatasa Alcalina , Diabetes Mellitus Tipo 2 , Adulto , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/etiología , Ayuno , Humanos , Incidencia , Persona de Mediana Edad , Obesidad/complicaciones
19.
Antibiotics (Basel) ; 11(5)2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-35625184

RESUMEN

BACKGROUND: Worldwide, microbes are becoming more challenging by acquiring virulent skills to adapt and develop antimicrobial resistance (AMR). This is a concern as AMR increases morbidity, mortality, and costs. Consequently, physicians need to be trained on appropriate antimicrobial prescribing, starting as medical students. OBJECTIVE: To evaluate medical students' confidence in antimicrobial prescribing and AMR. METHODS: Cross-sectional study assessing medical students' knowledge, perception, and confidence in prescribing antimicrobials and AMR in a Malaysian University. A universal sampling method was used. RESULTS: Most responding students believed that educational input regarding overall prescribing was sufficient. Regarding the principle of appropriate and accurate prescriptions, female medical students had less knowledge (odds ratio (OR) = 0.51; 95% confidence interval (CI) 0.25-0.99; p = 0.050). Year-IV and Year-V medical students had more excellent knowledge than Year-III students regarding confidence in potential antibiotic prescribing once qualified. Year-V students also showed an appreciably higher confidence in the broad principles of prescribing, including antibiotics for infectious diseases, compared to those in other years. CONCLUSION: Overall, medical students gain more knowledge and confidence regarding the potential prescribing of antimicrobials as their academic careers progress. This is important given concerns with the current excessive use of antimicrobials in Malaysia.

20.
Antibiotics (Basel) ; 11(1)2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35052982

RESUMEN

There is an increasing focus on researching children admitted to hospital with new variants of COVID-19, combined with concerns with hyperinflammatory syndromes and the overuse of antimicrobials. Paediatric guidelines have been produced in Bangladesh to improve their care. Consequently, the objective is to document the management of children with COVID-19 among 24 hospitals in Bangladesh. Key outcome measures included the percentage prescribed different antimicrobials, adherence to paediatric guidelines and mortality rates using purposely developed report forms. The majority of 146 admitted children were aged 5 years or under (62.3%) and were boys (58.9%). Reasons for admission included fever, respiratory distress and coughing; 86.3% were prescribed antibiotics, typically parenterally, on the WHO 'Watch' list, and empirically (98.4%). There were no differences in antibiotic use whether hospitals followed paediatric guidance or not. There was no prescribing of antimalarials and limited prescribing of antivirals (5.5% of children) and antiparasitic medicines (0.7%). The majority of children (92.5%) made a full recovery. It was encouraging to see the low hospitalisation rates and limited use of antimalarials, antivirals and antiparasitic medicines. However, the high empiric use of antibiotics, alongside limited switching to oral formulations, is a concern that can be addressed by instigating the appropriate programmes.

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