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1.
Antivir Ther ; 28(4): 13596535231189643, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37489502

RESUMO

In endemic areas, hepatitis C virus (HCV)/hepatitis B virus (HBV) coinfection is common, and patients with coinfection have a higher risk of developing liver disease such as hepatocellular carcinoma, liver fibrosis and cirrhosis. In such cases, HCV predominates, and HBV replication is suppressed by HCV. HCV core proteins and interferons that are activated by HCV are responsible for the suppression of HBV. Immunosuppression is also seen in patients with HCV and HBV coinfections. A decrease in HCV-neutralizing antibody response and circulation of Th1-like Tfh cells is observed in patients with HCV and HBV coinfection. Both viruses interacted in the liver, and treatment of HCV/HBV coinfection is genotype-based and complex due to the interaction of both viruses. In HCV-dominant cases, direct-acting antiviral drugs and peg interferon plus ribavirin are used for the treatment, with continuous monitoring of AST and ALT. HBV-dominant cases are less common and are treated with peg interferon and nucleoside nucleotide analogues with monitoring of AST and ALT. The SVR rate in HCV-HBV coinfection is higher than that in monoinfection when treated with direct-acting antiviral drugs. But there is a risk of reactivation of HBV during and after therapy. The rate of reactivation is lower in patients treated with direct-acting antiviral drugs as compared to those treated with peg interferon plus ribavirin. Biomarkers of HBV such as HBcrAg, HBV DNA and HBVpg RNA are not effective in the prediction of HBV reactivation; only the hepatitis B surface antigen titre can be used as a biomarker for HBV reactivation. HCV can also be reactive, but this is found in very rare cases in which HBV is present and is treated first.


Assuntos
Coinfecção , Hepatite C Crônica , Neoplasias Hepáticas , Humanos , Vírus da Hepatite B , Antivirais , Hepacivirus , Ribavirina , Cirrose Hepática , Interferons
2.
J Basic Microbiol ; 63(3-4): 276-291, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36316223

RESUMO

Bioactive molecules gain significance in pharmaceutical and nutraceutical industries for showcasing various beneficial biological properties including but not limited to anticancer, antimicrobial, antioxidant, antifungal, anti-inflammatory, cardioprotective, neuroprotective, and antidiabetic. However, the practice of using traditional approaches to produce bioactive molecules is gradually declining due to various limitations such as low product quality, high toxicity, low product yield, low efficiency, and product degradation. Thus, with the escalating demand for these bioactive molecules and active agents in food and other food-related industries, it has become a dire need for the scientific world to come up with novel approaches and strategies that cannot just improve the quality of these bioactives but also prepare them in a comparatively shorter time span. This review includes the latest approaches and techniques used either independently or in combinations for the extraction, purification, processing, and stability improvement of general bioactive molecules. Different parameters of these versatile techniques have been discussed with their effectiveness and work principles.


Assuntos
Suplementos Nutricionais , Indústria Alimentícia , Antioxidantes
3.
J Appl Microbiol ; 133(5): 2826-2834, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35916643

RESUMO

AIMS: Pakistan has the second highest prevalence of HCV with genotype 3a (GT-3a) being the most frequently circulating genotype. Currently, resistance-associated substitutions (RASs) are a major challenge in HCV treatment with direct-acting antivirals (DAAs). Sofosbuvir (SOF) is an FDA-approved NS5B nucleotide inhibitor. The aim of this study was to identify these RASs in the NS5B gene in naive and treated Pakistani HCV 3a isolates against SOF. METHODS AND RESULTS: Blood samples were collected from anti-HCV-positive patients, followed by HCV RNA isolation and real-time PCR quantification. HCV-positive patients were processed for HCV RNA genotyping, patients with genotype 3a were processed for NS5B gene amplification and sequencing. GT-3a was the most prevalent genotype (62.2%). S282T was identified in 2 (8.7%) patients, C316Y/G/R in 3 (13%), V321A and L320P in 1 (4.3%) each in SOF/RBV-resistant patients. Variants of S282 were detected in 3 (13%) of SOF/RBV-treated patients. While INF/RBV-associated mutations were also analysed, D244N, A333R and A334E were identified in 2 (9.5%), 3 (14.2%) and 7 (33.3%) in treatment-naive and 15 (65.2%), 7 (30.4%) and 5 (21.7%) treated patients, respectively. Q309R was observed only in one treatment-experienced patients. Some substitutions were present at higher frequency in both groups like N307G, K304R, A272D and R345H, considered that they do not have any role in sofosbuvir resistance. CONCLUSION: It was concluded that sofosbuvir RASs are present in Pakistani HCV GT-3a isolates, and they should be monitored carefully, especially in treatment-experienced patients, for further selection of treatment regimens. SIGNIFICANCE AND IMPACT OF STUDY: HCV RASs have been studied very well across the world but there is scarcity of data regarding this topic in Pakistani population, this study provides data regarding the prevalence of these RASs in Pakistani HCV isolates emphasizing the fact that these RASs must be carefully monitored before starting HCV treatment, especially in treatment failure patients.


Assuntos
Hepatite C Crônica , Sofosbuvir , Humanos , Sofosbuvir/uso terapêutico , Sofosbuvir/farmacologia , Hepacivirus/genética , Antivirais/uso terapêutico , Antivirais/farmacologia , Hepatite C Crônica/tratamento farmacológico , Farmacorresistência Viral/genética , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/farmacologia , Proteínas não Estruturais Virais/uso terapêutico , Genótipo , RNA
4.
Viral Immunol ; 32(10): 424-429, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31599707

RESUMO

Herpes simplex virus type 1 (HSV-1) infection activates a rapid stimulation of host innate immune responses and a delicate interplay between virus and host immune elements regulates the whole events. Although host immune elements play well in limiting the HSV-1 infection by interfering viral replication, they are still unable to remove the virus completely, because HSV-1 proteins are efficient enough to bypass the host antiviral immune responses and virus succeed to reactivate again from latency at opportune time. Type 1 interferon signaling pathway is the central point of innate immunity along with some of the activated neutrophils, monocytes, macrophages, and dendritic cells, and some natural killer cells play role, while the CD8+ T cells are crucial in adaptive immunity. In this review, the current knowledge of host and HSV-1 interaction has been described that how the host antiviral immune responses occur and what are the mechanisms of viral evasion adapted by virus to counteract with both arms of immunity.


Assuntos
Herpesvirus Humano 1/imunologia , Interações Hospedeiro-Patógeno/imunologia , Evasão da Resposta Imune , Imunidade Inata , Estomatite Herpética/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Humanos , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Transdução de Sinais/imunologia , Estomatite Herpética/virologia , Ativação Viral/imunologia , Latência Viral/imunologia , Replicação Viral/imunologia
5.
Crit Rev Eukaryot Gene Expr ; 29(5): 461-469, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32422002

RESUMO

The interaction between herpes simplex virus type 1 (HSV-1) and its host starts with the attachment of the virus for entry and spreading into host cells involving viral glycoproteins and host receptors. Once entered, it remains persistent as a latent infection throughout the host's life as it cannot be cleared completely by the immune system. Viral regulatory proteins and host factors determine whether the virus will enter into the acute or latent mode of infection. Acute viral infection is usually asymptomatic and self-limiting whereas latent infection may remain in the trigeminal ganglion of oropharyngeal mucosa, where it can be activated at any time depending upon the stimulus. Host innate and adaptive immune elements play important roles in limiting HSV-1 infection by interfering with viral replication but are unable to remove the virus completely. In this review, we update how the major proteins involved in entry and pathogenesis of viruses and immune responses against infection.


Assuntos
Imunidade Adaptativa , Herpes Simples/virologia , Herpesvirus Humano 1/imunologia , Interações Hospedeiro-Patógeno , Imunidade Inata , Proteínas Virais/metabolismo , Glicoproteínas/metabolismo , Herpes Simples/imunologia , Herpesvirus Humano 1/patogenicidade , Herpesvirus Humano 1/fisiologia , Humanos , Gânglio Trigeminal/virologia , Latência Viral , Replicação Viral
7.
Virol J ; 7: 283, 2010 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-20977704

RESUMO

BACKGROUND: Hepatitis delta virus (HDV) and Hepatitis B virus (HBV) co-infection is well known to induce a spectrum of acute and chronic liver diseases which further advance to cirrhosis, fulminant hepatitis and hepatocellular carcinoma (HCC). AIM: The aim of the present study was to determine the prevalence of hepatitis D virus super-infection among hepatitis B surface antigen (HBsAg) positive individuals in the highly populated province of Pakistan which is not well known. METHODS: Sera samples were subjected to HBsAg and anti-HDV screening and finally anti-HDV and HBsAg positive coinfected samples were used for HDV active RNA confirmation using nested polymerase chain reaction (PCR). RESULTS: Out of total 200 HBsAg positive samples by rapid device, 96 (48%) were also found reactive for HBsAg using enzyme linked immunosorbant assay (ELISA). Out of these HBsAg ELISA positive samples, 80 (88.8%) were anti-HDV ELISA positive which were then subjected to PCR. The amplification results further confirmed 24 (30%) samples to be HDV RNA positive. HDV super-infection was more common in male patients than female patients (81% VS 19%). CONCLUSION: The current study shows a high prevalence rate of HDV-HBV co-infection in Pakistan that tends to increase over time.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Hepatite B/complicações , Hepatite D/epidemiologia , Vírus Delta da Hepatite/isolamento & purificação , Adulto , Comorbidade , Ensaio de Imunoadsorção Enzimática , Feminino , Anticorpos Anti-Hepatite/sangue , Hepatite D/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Prevalência , RNA Viral/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Infect Genet Evol ; 10(8): 1242-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20727423

RESUMO

The continuously mutating nature of Hepatitis B virus (HBV) is responsible for the emergence of varying genotypes in different regions of the world affecting the disease outcome. The objective of the current study was to find out the pattern of HBV genotypes circulating in Pakistan. HBV genotypes were determined in HBV chronic patients of different age and gender from all the four different geographical regions (provinces) of Pakistan for a period of 2 years (2007-2009). Out of the total 3137 consecutive patients, 300 (175; 58.3% males and 125; 41.7% females) were randomly selected for HBV genotype A through H determination using molecular genotyping methods. Total 269 (89.6%) isolates were successfully genotyped where as 31 (10.3%) samples failed to generate a type-specific PCR band and were found untypable. Out of the successfully genotyped samples, 43 (14.3%) were with type A, 54 (18%) were with type B, 83 (27.6%) were with type C, 39 (13%) were with type D, 2 (0.6%) were with type E, 4 (1.3%) were with genotype F and total 44 (14.6%) were with mixed HBV infections. Of the mixed genotype infection cases, 16 were with genotypes A/D, 9 were B/C, six were A/D/F, five were with genotypes A/F, two were with A/B/D and B/E and one each for A/C as well as A/E genotypes. Four common genotypes of HBV found worldwide (A, B, C & D) were isolated from Pakistan along with uncommon genotypes E and F for the first time in Pakistan. Overall Genotype C is the most prevalent genotype. Genotypes B and C are predominant in Punjab & Balochistan and Khyber Pakhtoonkhwa, respectively whereas genotype A in Sindh.


Assuntos
DNA Viral/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/virologia , DNA Viral/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Feminino , Variação Genética , Genótipo , Geografia , Vírus da Hepatite B/classificação , Vírus da Hepatite B/isolamento & purificação , Humanos , Hepatopatias , Masculino , Técnicas de Diagnóstico Molecular , Epidemiologia Molecular , Paquistão/epidemiologia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
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