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1.
Virol J ; 20(1): 173, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537596

RESUMO

BACKGROUND: Several anti-retroviral drugs are available against Human immunodeficiency virus type-1, but have multiple adverse side effects. Hence, there is an incessant compulsion for effectual anti-retroviral agents with minimal or no intricacy. Traditionally, natural products have been the most successful source for the development of new medications. Withania somnifera, also known as Ashwagandha, is the utmost treasured medicinal plant used in Ayurveda, which holds the potential to give adaptogenic, immunomodulatory, and antiviral effects. However, its effect on HIV-1 replication at the cellular level has never been explored. Herein, we focused on the anti-HIV-1 activity and the probable mechanism of action of hydroalcoholic and aqueous extracts of Withania somnifera roots and its phytomolecules. METHODS: The cytotoxicity of the extracts was determined through MTT assay, while the in vitro anti-HIV-1 activity was assessed in TZM-bl cells against the HIV-1 strains of X4 and R5 subtypes. Results were confirmed in peripheral blood mononuclear cells, using the HIV-1 p24 antigen assay. Additionally, the mechanism of action was determined through the Time of Addition assay, which was further validated through the series of enzymatic assays, i.e. HIV-1 Integrase, Reverse transcriptase, and Protease assays. To explore the role of the identified active metabolites of Withania somnifera in antiretroviral activity, molecular docking analyses were performed against these key HIV-1 replication enzymes. RESULTS: The hydroalcoholic and aqueous extracts of Withania somnifera roots were found to be safer at the sub-cytotoxic concentrations and exhibited their ability to inhibit replication of two primary isolates of HIV-1 through cell-associated and cell-free assays, in dose-dependent kinetics. Several active phytomolecules found in Withania somnifera successfully established hydrogens bonds in the active binding pocket site residues responsible for the catalytic activity of HIV replication and therefore, signifying their role in the attenuation of HIV-1 infection as implied through the in silico molecular docking studies. CONCLUSIONS: Our research identified both the hydroalcoholic and aqueous extracts of Withania somnifera roots as potent inhibitors of HIV-1 infection. The in silico analyses also indicated the key components of Withania somnifera with the highest binding affinity against the HIV-1 Integrase by 12-Deoxywithastramonolide and 27-Hydroxywithanone, HIV-1 Protease by Ashwagandhanolide and Withacoagin, and HIV-1 Reverse transcriptase by Ashwagandhanolide and Withanolide B, thereby showing possible mechanisms of HIV-1 extenuation. Overall, this study classified the role of Withania somnifera extracts and their active compounds as potential agents against HIV-1 infection.


Assuntos
HIV-1 , Plantas Medicinais , Viroses , Withania , Humanos , Withania/química , Withania/metabolismo , Leucócitos Mononucleares , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antirretrovirais
2.
Cell Microbiol ; 21(12): e13101, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31424151

RESUMO

RNA interference (RNAi) is an evolutionary ancient innate immune response in plants, nematodes, and arthropods providing natural protection against viral infection. Viruses have also gained counter-defensive measures by producing virulence determinants called viral-suppressors-of-RNAi (VSRs). Interestingly, in spite of dominance of interferon-based immunity over RNAi in somatic cells of higher vertebrates, recent reports are accumulating in favour of retention of the antiviral nature of RNAi in mammalian cells. The present study focuses on the modulation of intracellular RNAi during infection with rotavirus (RV), an enteric virus with double-stranded RNA genome. Intriguingly, a time point-dependent bimodal regulation of RNAi was observed in RV-infected cells, where short interfering RNA (siRNA)-based RNAi was rendered non-functional during early hours of infection only to be reinstated fully beyond that early infection stage. Subsequent investigations revealed RV nonstructural protein 1 to serve as a putative VSR by associating with and triggering degradation of Argonaute2 (AGO2), the prime effector of siRNA-mediated RNAi, via ubiquitin-proteasome pathway. The proviral significance of AGO2 degradation was further confirmed when ectopic overexpression of AGO2 significantly reduced RV infection. Cumulatively, the current study presents a unique modulation of host RNAi during RV infection, highlighting the importance of antiviral RNAi in mammalian cells.


Assuntos
Proteínas Argonautas/genética , Interferência de RNA/fisiologia , Infecções por Rotavirus/genética , Infecções por Rotavirus/virologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Células HEK293 , Células HT29 , Haplorrinos , Interações Hospedeiro-Patógeno/genética , Humanos , RNA de Cadeia Dupla/genética , RNA Interferente Pequeno/genética , RNA Viral/genética
4.
J Virol ; 89(6): 3356-65, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25589644

RESUMO

UNLABELLED: Hepatitis C virus (HCV) is a serious global health problem and establishes chronic infection in a significant number of infected humans worldwide. Interferon (IFN) and IFN-stimulated genes (ISGs) are amplified during HCV infection but fail to eliminate virus from the liver in a large number of infected patients, and the mechanism is not fully understood. MicroRNAs (miRNAs) have been implicated in the control of many biological processes, including IFN signaling. To gain more insights into the role of cellular miRNAs in possible countermeasures of HCV for suppression of the host antiviral response, a miRNA array was performed by using primary human hepatocytes infected with in vitro cell culture-grown HCV. A group of miRNAs were modulated in HCV-infected primary human hepatocytes. We focused on miR-373, as this miRNA was significantly upregulated in HCV-infected primary human hepatocytes. Here, we analyzed the function of miR-373 in the context of HCV infection. HCV infection upregulates miR-373 expression in hepatocytes and HCV-infected liver biopsy specimens. Furthermore, we discovered that miR-373 directly targets Janus kinase 1 (JAK1) and IFN-regulating factor 9 (IRF9), important factors in the IFN signaling pathway. The upregulation of miR-373 by HCV also inhibited STAT1 phosphorylation, which is involved in ISG factor 3 (ISGF3) complex formation and ISG expression. The knockdown of miR-373 in hepatocytes enhanced JAK1 and IRF9 expression and reduced HCV RNA replication. Taken together, our results demonstrated that miR-373 is upregulated during HCV infection and negatively regulated the type I IFN signaling pathway by suppressing JAK1 and IRF9. Our results offer a potential therapeutic approach for antiviral intervention. IMPORTANCE: Chronic HCV infection is one of the major causes of end-stage liver disease worldwide. Although the recent introduction of direct-acting antiviral (DAA) therapy is extremely encouraging, some infected individuals do not respond to this therapy. Furthermore, these drugs target HCV nonstructural proteins, and with selective pressure, the virus may develop a resistant strain. Therefore, understanding the impairment of IFN signals will help in designing additional therapeutic modalities. In this study, we provide evidence of HCV-mediated upregulation of miR-373 and show that miR-373 impairs IFN signaling by targeting JAK1/IRF9 molecules. The knockdown of miR-373 inhibited HCV replication by upregulating interferon-stimulating gene expression. Together, these results provided new mechanistic insights into the role of miR-373 in HCV infection and suggest a new potential target against HCV infection.


Assuntos
Hepacivirus/fisiologia , Hepatite C/genética , Janus Quinases/metabolismo , MicroRNAs/metabolismo , Fator de Transcrição STAT1/metabolismo , Adulto , Feminino , Hepacivirus/genética , Hepatite C/enzimologia , Hepatite C/metabolismo , Hepatócitos/enzimologia , Hepatócitos/metabolismo , Hepatócitos/virologia , Interações Hospedeiro-Patógeno , Humanos , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/genética , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/metabolismo , Janus Quinases/genética , Masculino , MicroRNAs/genética , Fator de Transcrição STAT1/genética , Transdução de Sinais
6.
Arch Virol ; 161(10): 2773-85, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27447463

RESUMO

Species A rotaviruses (RVA) are the most important cause of acute gastroenteritis in the young of humans and many animal species globally. G1P[8], G2P[4], G3P[8], G4P[8], G9P[6/8] and G12P[6/8] are the predominantly isolated genotypes throughout the world including India. Unusual genotypes from different host species such as G5, G6, G8, G10 and G11 have also been reported in humans with low frequency. In the present study, among >650 RVA positive stool samples collected from children with diarrhea in Kolkata, India, during 2014, two isolates each of the genotype G12P[11] and G10P[14] were obtained and their genomes completely sequenced. The full genotype constellations were G12-P[11]-I1-R1-C1-M2-A1-N1-T2-E1-H1 and G12-P[11]-I1-R1-C1-M1-A5-N1-T1-E1-H1 for G12P[11] viruses, suggesting several reassortments between Wa- and DS-1-like human RVA strains, including possible reassortment of a simian NSP1 gene. The G10P[14] viruses (G10-P[14]-I2-R2-C2-M2-A11-N2-T6-E2-H3) were found to contain multiple genes closely related to RVAs of artiodactyl origin, highlighting the role of inter-host species transmissions of RVAs. From the G/P constellation of all RVA isolates, it could be concluded that approximately one quarter had likely arisen from reassortment events in vivo among RVAs of 'usual' genotypes.


Assuntos
Diarreia/virologia , Genótipo , Vírus Reordenados/classificação , Vírus Reordenados/genética , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/genética , Pré-Escolar , Diarreia/epidemiologia , Evolução Molecular , Fezes/virologia , Feminino , Genoma Viral , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , Masculino , RNA Viral/genética , Vírus Reordenados/isolamento & purificação , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Análise de Sequência de DNA
7.
J Virol ; 88(14): 7929-40, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24789793

RESUMO

Hepatitis C virus (HCV)-induced chronic liver disease is one of the leading causes of hepatocellular carcinoma (HCC). The molecular events leading to HCC following chronic HCV infection remain poorly defined. MicroRNAs (miRNAs) have been implicated in the control of many biological processes, and their deregulation is associated with different viral infections. In this study, we observed that HCV infection of hepatocytes transcriptionally downregulates miR-181c expression by modulating CCAAT/enhancer binding protein ß (C/EBP-ß). Reduced expression of the pri-miR-181c transcript was noted following HCV infection. In silico prediction suggests that homeobox A1 (HOXA1) is a direct target of miR-181c. HOXA1 is a member of the homeodomain-containing transcription factor family and possesses pivotal roles in normal growth, development, and differentiation of mammalian tissues. Our results demonstrated that HOXA1 expression is enhanced in HCV-infected hepatocytes. Exogenous expression of the miR-181c mimic inhibits HOXA1 and its downstream molecules STAT3 and STAT5, which are involved in cell growth regulation. Interestingly, overexpression of miR-181c inhibited HCV replication by direct binding with E1 and NS5A sequences. Furthermore, accumulation of HCV genotype 2a RNA with miR-181c was observed in an RNA-induced silencing complex in Huh7.5 cells. Our results provide new mechanistic insights into the role of miR-181c in HCV-hepatocyte interactions, and miR-181c may act as a target for therapeutic intervention. Importance: Chronic HCV infection is one of the major causes of end-stage liver disease, including hepatocellular carcinoma. An understanding of the molecular mechanisms of HCV-mediated hepatocyte growth promotion is necessary for therapeutic intervention against HCC. In this study, we have provided evidence of HCV-mediated transcriptional downregulation of miR-181c. HCV-infected liver biopsy specimens also displayed lower expression levels of miR-181c. We have further demonstrated that inhibition of miR-181c upregulates homeobox A1 (HOXA1), which is important for hepatocyte growth promotion. Exogenous expression of miR-181c inhibited HCV replication by directly binding with HCV E1 and NS5A sequences. Taken together, our results provided new mechanistic insights for an understanding of the role of miR-181c in HCV-hepatocyte interactions and revealed miR-181c as a potential target for therapeutic intervention.


Assuntos
Hepacivirus/fisiologia , Hepatócitos/fisiologia , Hepatócitos/virologia , Proteínas de Homeodomínio/biossíntese , Interações Hospedeiro-Patógeno , MicroRNAs/antagonistas & inibidores , Fatores de Transcrição/biossíntese , Adulto , Biópsia , Proliferação de Células , Biologia Computacional , Redes Reguladoras de Genes , Hepatite C/patologia , Humanos , Fígado/patologia
8.
Opt Express ; 23(7): 8272-80, 2015 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-25968665

RESUMO

Averaging and shifting the refractive index profiles of quasiperiodic structure reveals the formation of several localized modes in the reflectivity spectrum and were used to generate different spectral barcodes. By associating the depth and wavelength of the observed resonant modes to the thickness and position of blackbars, respectively, the possibility to generate multiple codes has been shown. An experimental verification was carried out with multilayered dielectric porous silicon structures with reflectivity spectra revealing unique photonic fingerprints.

9.
J Virol ; 87(22): 12284-90, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24006444

RESUMO

Hepatitis C virus (HCV)-mediated chronic liver disease is a global health problem, and inflammation is believed to be an important player in disease pathogenesis. HCV infection often leads to severe fibrosis/cirrhosis and hepatocellular carcinoma, although the mechanisms for advancement of disease are not fully understood. The proinflammatory cytokines interleukin-1ß (IL-1ß) and IL-18 have critical roles in establishment of inflammation. In this study, we examined induction of IL-1ß/IL-18 secretion following HCV infection. Our results demonstrated that monocyte-derived human macrophages (THP-1) incubated with cell culture-grown HCV enhance the secretion of IL-1ß/IL-18 into culture supernatants. A similar cytokine release was also observed for peripheral blood mononuclear cell (PBMC)-derived primary human macrophages and Kupffer cells (liver-resident macrophages) upon incubation with HCV. THP-1 cells incubated with HCV led to caspase-1 activation and release of proinflammatory cytokines. Subsequent studies demonstrated that HCV induces pro-IL-1ß and pro-IL-18 synthesis via the NF-κB signaling pathway in macrophages. Furthermore, introduction of HCV viroporin p7 RNA into THP-1 cells was sufficient to cause IL-1ß secretion. Together, our results suggested that human macrophages exposed to HCV induce IL-1ß and IL-18 secretion, which may play a role in hepatic inflammation.


Assuntos
Carcinoma Hepatocelular/metabolismo , Hepacivirus/fisiologia , Hepatite C/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Fígado/metabolismo , Macrófagos/metabolismo , Western Blotting , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Hepatite C/genética , Hepatite C/virologia , Humanos , Interleucina-18/genética , Interleucina-1beta/genética , Células de Kupffer , Fígado/patologia , Fígado/virologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Macrófagos/patologia , Macrófagos/virologia , NF-kappa B/genética , NF-kappa B/metabolismo , RNA Mensageiro/genética , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais
10.
Healthcare (Basel) ; 12(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38391789

RESUMO

India continues to grapple with a significant burden of HIV infections. Despite notable progress in prevention and treatment efforts, multiple challenges, such as high-risk populations, inadequate testing facilities, and limited access to healthcare in remote areas, persist. Though the Government of India offers HIV-1 plasma viral load testing at various medical centers, aiding treatment decisions and monitoring antiretroviral therapy effectiveness, enhancing care for individuals living with HIV under the National AIDS Control Program (NACP), the nation's large population and diverse demographics further complicate its outreach and response. Hence, strategic interventions and alternative methods of testing remain crucial to curbing HIV transmission and improving the quality of life for those affected. Dried blood spot (DBS) sampling has emerged as a convenient and cost-effective alternative for HIV-1 viral load testing, revolutionizing the landscape of diagnostic and monitoring strategies for HIV infection. Though the plasma-based viral load remains the gold standard for monitoring HIV-1, DBS-based HIV-1 viral load testing holds immense promise for improving access to care, particularly in resource-limited settings where traditional plasma-based methods may be logistically challenging. DBS entails the collection of a small volume of blood onto filter paper, followed by drying and storage. This approach offers numerous advantages, including simplified sample collection, transportation, and storage, reducing the need for cold-chain logistics. Recent studies have demonstrated the feasibility and accuracy of DBS-based HIV-1 viral load testing, revealing a strong correlation between DBS and plasma measurements. Its implementation can enhance the early detection of treatment failure, guide therapeutic decisions, and ultimately contribute to better clinical outcomes for HIV-infected individuals. Hence, this review explores the principles, advancements, feasibility, and implications of DBS-based HIV-1 viral load testing.

11.
Drug Deliv Transl Res ; 14(7): 1888-1908, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38161197

RESUMO

Atazanavir or ATV is an FDA-approved, HIV-1 protease inhibitor that belongs to the azapeptide group. Over time, it has been observed that ATV can cause multiple adverse side effects in the form of liver diseases including elevations in serum aminotransferase, indirect hyper-bilirubinemia, and idiosyncratic acute liver injury aggravating the underlying chronic viral hepatitis. Hence, there is an incessant need to explore the safe and efficacious method of delivering ATV in a controlled manner that may reduce the proportion of its idiosyncratic reactions in patients who are on antiretroviral therapy for years. In this study, we assessed ATV formulation along with Rosemary oil to enhance the anti-HIV-1 activity and its controlled delivery through self-nanoemulsifying drug delivery system or SNEDDS to enhance its oral bioavailability. While the designing, development, and characterization of ATV-SNEDDS were addressed through various evaluation parameters and pharmacokinetic-based studies, in vitro cell-based experiments assured the safety and efficacy of the designed ATV formulation. The study discovered the potential of ATV-SNEDDS to inhibit HIV-1 infection at a lower concentration as compared to its pure counterpart. Simultaneously, we could also demonstrate the ATV and Rosemary oil providing leads for designing and developing such formulations for the management of HIV-1 infections with the alleviation in the risk of adverse reactions.


Assuntos
Sulfato de Atazanavir , Infecções por HIV , HIV-1 , Sulfato de Atazanavir/farmacocinética , Sulfato de Atazanavir/administração & dosagem , Infecções por HIV/tratamento farmacológico , Humanos , Animais , HIV-1/efeitos dos fármacos , Emulsões , Sistemas de Liberação de Medicamentos , Óleos Voláteis/administração & dosagem , Óleos Voláteis/química , Óleos Voláteis/farmacocinética , Óleos Voláteis/farmacologia , Masculino , Inibidores da Protease de HIV/administração & dosagem , Inibidores da Protease de HIV/farmacocinética , Inibidores da Protease de HIV/uso terapêutico , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/farmacocinética , Fármacos Anti-HIV/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Sistemas de Liberação de Fármacos por Nanopartículas/química
12.
FEBS Lett ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789398

RESUMO

Nanotechnology offers promising avenues for enhancing drug delivery systems, particularly in HIV-1 treatment. This study investigates a nanoemulsified formulation combining epigallocatechin gallate (EGCG) with dolutegravir (DTG) for managing HIV-1 infection. The combinatorial interaction between EGCG and DTG was explored through cellular, enzymatic, and molecular studies. In vitro assays demonstrated the potential of a dual drug-loaded nanoemulsion, NE-DTG-EGCG, in inhibiting HIV-1 replication, with EGCG serving as a supplementary treatment containing DTG. In silico molecular interaction studies highlighted EGCG's multifaceted inhibitory potential against HIV-1 integrase and reverse transcriptase enzymes. Further investigations are needed to validate the formulation's efficacy across diverse contexts. Overall, by integrating nanotechnology into drug delivery systems, this study represents a significant advancement in managing HIV-1 infection.

13.
Heliyon ; 10(2): e24350, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38288021

RESUMO

Background: Diosgenin, an essential sapogenin steroid with significant biological implications, is composed of a hydrophilic sugar moiety intricately linked to a hydrophobic steroid aglycone. While the antiviral properties of diosgenin against numerous RNA viruses have been extensively documented, its potential in combating Human Immunodeficiency Virus infections remains unexplored. Experimental procedure: This current investigation presents a comprehensive and systematic analysis of extracts derived from the leaves of Helicteres isora, which are notably enriched with diosgenin. Rigorous methodologies, including established chromatographic techniques and Fourier-transform infrared spectroscopy were employed for the characterization of the active diosgenin compound followed by molecular interaction analyses with the key HIV enzymes and mechanistic validation of HIV inhibition. Key results: The inhibitory effects of extracted diosgenin on the replication of HIV-1 were demonstrated using a permissive cellular system, encompassing two distinct subtypes of HIV-1 strains. Computational analyses involving molecular interactions highlighted the substantial occupancy of critical active site pocket residues within the key HIV-1 proteins by diosgenin. Additionally, the mechanistic underpinnings of diosgenin activity in conjunction with standard controls were elucidated through specialized colorimetric assays, evaluating its impact on HIV-1 Reverse Transcriptase and Integrase enzymes. Conclusions: To our current state of knowledge, this study represents the inaugural demonstration of the anti-HIV efficacy inherent to diosgenin found in the leaves of Helicteres isora, and can be taken further for drug design and development for the management of HIV infection.

14.
Viruses ; 16(5)2024 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-38793546

RESUMO

Chronic immune activation in tuberculosis (TB) associated with human immunodeficiency virus (HIV) infection (HIV/TB) modifies their clinical course. We prospectively measured osteopontin (OPN), full-length galectin-9 (FL-Gal9), and total-Gal9 (T-Gal9) levels in 32 patients with HIV/TB coinfection treated with anti-tuberculosis and antiretroviral therapies over 6-18 months to determine the amelioration of inflammatory conditions in response to the therapies. We observed a significant time-dependent decrease in FL-Gal9 in both pulmonary TB (PTB, n = 20) and extrapulmonary TB (EPTB, n = 12) patients. The levels of T-Gal9, OPN, and CRP decreased significantly after treatment in only PTB patients. We calculated the inflammatory score (INS) indicating immunologic recovery based on the decline in OPN, FL-Gal9, T-Gal9, and CRP levels. Baseline levels of T-Gal9 and OPN positively correlated with INS in all TB and only PTB patients, respectively, indicating that their levels predict better recovery. In contrast, FL-Gal9 levels at the second visit negatively correlated with INS in EPTB patients. The decrease rate in OPN levels at the second visit also correlated positively with INS in PTB patients. Women showed a higher INS and lower levels of FL-Gal9 than men. The patients with moderate grade severity on chest X-ray had higher CD4 cell numbers than those with limited grade severity. Monitoring these markers will help to predict and assess the response to therapy as well as to devise strategies to reduce the complications caused by chronic immune activation in patients with HIV/TB coinfection.


Assuntos
Coinfecção , Galectinas , Infecções por HIV , Osteopontina , Tuberculose , Humanos , Infecções por HIV/complicações , Infecções por HIV/sangue , Feminino , Masculino , Coinfecção/sangue , Adulto , Osteopontina/sangue , Galectinas/sangue , Tuberculose/sangue , Tuberculose/complicações , Pessoa de Meia-Idade , Estudos Prospectivos , Biomarcadores/sangue , Antituberculosos/uso terapêutico , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/imunologia , Proteína C-Reativa/análise
15.
J Med Virol ; 85(3): 537-45, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23280762

RESUMO

Group A rotaviruses are the major cause of childhood gastroenteritis worldwide. Due to close proximity of human and cattle in rural areas of developing countries like India, interspecies transmission or zoonotic transmission is a major source of rapid generation of reassortants and genetic or antigenic variants. Previously, many human group A rotaviruses were found with porcine or bovine characteristics from eastern and north-eastern India. In this study, four unusual human G8P[4] strains were identified which had artiodactyl-like origins. During an ongoing community based surveillance for epidemiological profiling of diarrheal pathogens, these unusual human group A rotavirus G8P[4] strains were detected from the stool samples of 3-14 months old children with acute diarrhea in Sonarpur, eastern India. Analysis of eleven complete and/or partial gene segments of these unusual G8P[4] strains were done by reverse transcription-PCR (RT-PCR) followed by nucleotide sequencing and phylogenetic analysis. The VP7 nucleotide sequences revealed a close phylogenetic relationship to the G8P[7] porcine strain D-1 and bovine strain KJ59-2 from South Korea. Whereas the VP4 gene segments were also related closely to human rotavirus prototype strain DS-1. Other nine gene segments of these G8P[4] rotaviruses were related closely to either animal or animal-derived rotavirus members of the DS-1-like family. These results suggest that origin of these G8P[4] strains might have been resulted from multiple reassortment events between artiodactyls and ruminant-derived reassortant human rotaviruses. To date, this is the first report of G8P[4] rotavirus from India and the first genomic analysis of G8P[4] strains from Asian continent.


Assuntos
Gastroenterite/diagnóstico , Gastroenterite/virologia , Infecções por Rotavirus/diagnóstico , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/isolamento & purificação , Zoonoses/transmissão , Animais , Bovinos , Evolução Molecular , Fezes/virologia , Feminino , Genótipo , Humanos , Índia , Lactente , Masculino , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Vírus Reordenados/classificação , Vírus Reordenados/genética , Vírus Reordenados/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/genética , Análise de Sequência de DNA , Suínos , Zoonoses/virologia
16.
Opt Express ; 21(14): 17324-39, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23938579

RESUMO

Tunability of the optical response of multilayered photonic structures has been compared with sequential (SQ) and superposition (SP) addition of refractive index profile functions. The optical response of the composite multilayered structure, formed after the SP addition of the two Bragg type refractive index profile functions has been studied as a function of percentage overlap and relative shift between the profiles. Apart from the substantial advantage in terms of the reduced physical thickness of the SP composite structures (over the SQ addition), at certain optimum values of relative shift, photonic structures with better quality factor resonant modes or a broader PBG could be designed. Similar analysis has been extended for rugate filters as well. The experimental verification of the optical response, was carried out through multilayered dielectric porous silicon structures fabricated by electrochemical anodization.


Assuntos
Manufaturas/análise , Modelos Teóricos , Simulação por Computador , Luz , Espalhamento de Radiação
17.
Viruses ; 15(8)2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37632059

RESUMO

As rightly stated by the author Mira Grant in her novel Countdown, "There is nothing so patient, in this world or any other, as a virus searching for a host" [...].


Assuntos
Antivirais , Evasão da Resposta Imune , Humanos , Feminino , Antivirais/farmacologia , Interações entre Hospedeiro e Microrganismos
18.
Pathogens ; 12(4)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37111450

RESUMO

HPV, or Human Papilloma Virus, has been the primary causative agent of genital warts and cervical cancer worldwide. It is a sexually transmitted infection mainly affecting women of reproductive age group, also infecting men and high-risk group individuals globally, resulting in high mortality. In recent years, HPV has also been found to be the major culprit behind anogenital cancers in both gender and oropharyngeal and colorectal cancers. Few studies have reported the incidence of HPV in breast cancers as well. For a few decades, the burden of HPV-associated malignancies has been increasing at an alarming rate due to a lack of adequate awareness, famine vaccine coverage and hesitancy. The effectiveness of currently available vaccines has been limited to prophylactic efficacy and does not prevent malignancies associated with post-exposure persistent infection. This review focuses on the current burden of HPV-associated malignancies, their causes and strategies to combat the growing prevalence of the cancers. With the advent of new technologies associated with treatment pertaining to therapeutic interventions and employing effective vaccine coverage, the burden of this disease may be reduced in the population.

19.
Heliyon ; 9(5): e16027, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37215829

RESUMO

The advent of Highly Active Antiretroviral Therapy has majorly contributed towards reducing the morbidity and mortality associated with HIV infected people, thus improving the quality of their life. Still, the eradication of HIV infection has not been achieved due to some important limitations such as non-adherence to therapy, cellular toxicity, restricted bioavailability of antiretroviral drugs and emergence of drug resistant viruses. Moreover, persistence of latent HIV-reservoirs even under antiviral-drug pressure is the major obstacle in HIV cure. Currently used antiretrovirals can suppress the viral replication in activated CD4+ cells, however, it has been observed that the available antiretroviral therapy appears inadequate to reduce latent reservoirs established in resting memory CD4+ T cells. Therefore, for eradication or reduction of latent reservoirs many immunotherapeutic and pharmacologic approaches including latency reversing agents are being studied constantly. Additionally, promising therapeutic strategies including discovery of novel drugs and drug targets are continuously being explored. Therefore, preclinical testing has become an important step of drug development process, continuously demanding innovative, but less time consuming evaluation strategies. Present review attempts to gather and line-up the information on existing cell-based methodologies applied for assessing drug candidates for their antiretroviral potential. Further, we intend to outline the advanced and reliable cell based methodologies that would expedite the process of discovery and development of antiretrovirals.

20.
Artigo em Inglês | MEDLINE | ID: mdl-37622690

RESUMO

AIMS: The aim of this study is to develop a novel antiviral strategy capable of efficiently targeting a broad set of SARS-CoV-2 variants. BACKGROUND: Since the first emergence of SARS-CoV-2, it has rapidly transformed into a global pandemic, posing an unprecedented threat to public health. SARS-CoV-2 is prone to mutation and continues to evolve, leading to the emergence of new variants capable of escaping immune protection achieved due to previous SARS-CoV-2 infections or by vaccination. OBJECTIVE: RNA interference (RNAi) is a remarkable biological mechanism that can induce gene silencing by targeting complementary mRNA and inhibiting its translation. METHOD: In this study, using the computational approach, we predicted the most efficient siRNA capable of inhibiting SARS-CoV-2 variants of concern (VoCs). RESULT: The presented siRNA was characterized and evaluated for its thermodynamic properties, offsite-target hits, and in silico validation by molecular docking and molecular dynamics simulations (MD) with Human AGO2 protein. CONCLUSION: The study contributes to the possibility of designing and developing an effective response strategy against existing variants of concerns and preventing further.

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