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1.
BMC Infect Dis ; 23(1): 872, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087193

RESUMO

BACKGROUND: The corona virus SARS-CoV-2 is the causative agent of recent most global pandemic. Its genome encodes various proteins categorized as non-structural, accessory, and structural proteins. The non-structural proteins, NSP1-16, are located within the ORF1ab. The NSP3, 4, and 6 together are involved in formation of double membrane vesicle (DMV) in host Golgi apparatus. These vesicles provide anchorage to viral replicative complexes, thus assist replication inside the host cell. While the accessory genes coded by ORFs 3a, 3b, 6, 7a, 7b, 8a, 8b, 9b, 9c, and 10 contribute in cell entry, immunoevasion, and pathological progression. METHODS: This in silico study is focused on designing sequence specific siRNA molecules as a tool for silencing the non-structural and accessory genes of the virus. The gene sequences of NSP3, 4, and 6 along with ORF3a, 6, 7a, 8, and 10 were retrieved for conservation, phylogenetic, and sequence logo analyses. siRNA candidates were predicted using siDirect 2.0 targeting these genes. The GC content, melting temperatures, and various validation scores were calculated. Secondary structures of the guide strands and siRNA-target duplexes were predicted. Finally, tertiary structures were predicted and subjected to structural validations. RESULTS: This study revealed that NSP3, 4, and 6 and accessory genes ORF3a, 6, 7a, 8, and 10 have high levels of conservation across globally circulating SARS-CoV-2 strains. A total of 71 siRNA molecules were predicted against the selected genes. Following rigorous screening including binary validations and minimum free energies, final siRNAs with high therapeutic potential were identified, including 7, 2, and 1 against NSP3, NSP4, and NSP6, as well as 3, 1, 2, and 1 targeting ORF3a, ORF7a, ORF8, and ORF10, respectively. CONCLUSION: Our novel in silico pipeline integrates effective methods from previous studies to predict and validate siRNA molecules, having the potential to inhibit viral replication pathway in vitro. In total, this study identified 17 highly specific siRNA molecules targeting NSP3, 4, and 6 and accessory genes ORF3a, 7a, 8, and 10 of SARS-CoV-2, which might be used as an additional antiviral treatment option especially in the cases of life-threatening urgencies.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , RNA Interferente Pequeno/genética , Filogenia , Perfilação da Expressão Gênica
2.
Environ Sci Pollut Res Int ; 30(20): 57587-57598, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36971936

RESUMO

The current study is focused on the use of the Caryota mitis Lour. (Fishtail palm) flower extract as a reducing agent for the preparation of manganese dioxide (MnO2) nanoparticles. Scanning electron microscopy (SEM), four-phase infrared analysis (FT-IR), and x-ray diffraction (XRD) methods were used to characterize the MnO2 nanoparticles. The nature of MnO2 nanoparticles was revealed by an absorption peak at 590 nm in a spectrophotometer (A1000). Then, these MnO2 nanoparticles were applied to decolorize the crystal violet dye. At 0.004% dye concentration, pH 4, and concentration of MnO2 nanoparticles of 0.005 g/L at temperatures of 50 °C, the target dye was decolorized by 91.3%. Percent reductions in COD and TOC were found to be 92.1% and 90.6%, respectively. Finally, the dye decolorization pathway was proposed based on the experimental findings.


Assuntos
Nanopartículas , Óxidos , Óxidos/química , Violeta Genciana , Compostos de Manganês/química , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas/química
3.
Viral Immunol ; 36(2): 110-121, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36626119

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic. There are four structural proteins of the virus: spike, envelope, membrane, and nucleocapsid proteins. Various vaccines were designed and are effectively being used against the spike protein of the virus. However, several vaccine-related complications have been reported worldwide. Assuming that the structural integrity of the whole protein might be contributing to these complications, this study was performed to design epitopes using the S2 domain of the spike protein, which could trigger a strong immune response. We have also predicted antigenic and allergenic properties of the selected epitopes. A total of 49 B cell epitopes passing antigenicity and other assessment filters were found using three methods. Among them, RDLICAQ had the highest antigenicity score (1.1443). However, only one cytotoxic T lymphocyte epitope, RSFIEDLLF, passed the essential filters with an antigenicity score of 0.5782 to show an appropriate immune response for T cells, while among 21 helper T cell lymphocyte epitopes that were filtered, FAMQMAYRFNGIGVT showed the highest (1.3688) antigenicity score. Conservation analysis revealed that the S2 domain is significantly conserved, thus making it an ideal candidate for vaccine development. We have also designed a vaccine construct based on the best suiting components found during the whole study. This construct and S2 domain solely can be future subjects of interest or might be included in a subunit cocktail formulation for attaining unabridged immunogenicity.


Assuntos
COVID-19 , Vacinas Virais , Humanos , SARS-CoV-2/genética , COVID-19/prevenção & controle , Glicoproteína da Espícula de Coronavírus/química , Epitopos de Linfócito B/química , Epitopos de Linfócito T , Simulação de Acoplamento Molecular
4.
Micromachines (Basel) ; 11(6)2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32570813

RESUMO

Gas sensors are critical components when adhering to health safety and environmental policies in various manufacturing industries, such as the petroleum and oil industry; scent and makeup production; food and beverage manufacturing; chemical engineering; pollution monitoring. In recent times, gas sensors have been introduced to medical diagnostics, bioprocesses, and plant disease diagnosis processes. There could be an adverse impact on human health due to the mixture of various gases (e.g., acetone (A), ethanol (E), propane (P)) that vent out from industrial areas. Therefore, it is important to accurately detect and differentiate such gases. Towards this goal, this paper presents a novel electronic nose (e-nose) detection method to classify various explosive gases. To detect explosive gases, metal oxide semiconductor (MOS) sensors are used as reliable tools to detect such volatile gases. The data received from MOS sensors are processed through a multivariate analysis technique to classify different categories of gases. Multivariate analysis was done using three variants-differential, relative, and fractional analyses-in principal components analysis (PCA). The MOS sensors also have three different designs: loading design, notch design, and Bi design. The proposed MOS sensor-based e-nose accurately detects and classifies three different gases, which indicates the reliability and practicality of the developed system. The developed system enables discrimination of these gases from the mixture. Based on the results from the proposed system, authorities can take preventive measures to deal with these gases to avoid their potential adverse impacts on employee health.

5.
Eur J Gastroenterol Hepatol ; 31(3): 389-392, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30383555

RESUMO

INTRODUCTION: Hepatitis G virus (HGV) infection appears to be common in patients with chronic hepatitis C virus (HCV) infection. The aim of this study was to investigate the prevalence of HCV/HGV in patients with chronic hepatitis C (CHC) in Pakistan and to look for possible associations with various clinical and histopathological changes in HCV/HGV coinfection and HCV infection. PATIENTS AND METHODS: The present study included 136 patients. Clinical, biochemical, virological and histological findings were compared between patients coinfected with HCV/HGV and patients with HCV alone. RESULTS: Of the 136 patients with CHC, 16 (11.76%) were coinfected with HCV/HGV. The mean age of coinfected patients was lower than in patients with HCV alone. HCV/HGV coinfected patients did not show significant differences in sex, clinical presentation, biochemical markers, and liver fibrosis as compared to those with HCV infection. Only the mean values of platelets count, mean corpuscular hemoglobin (MCH), and MCH concentration markers were significantly different in HCV/HGV coinfected patients as compare to patients with HCV alone. CONCLUSION: It was found that 11.76% of patients with CHC in Pakistan were associated with HCV/HGV coinfection. No significant differences were observed in clinical and histological features except for platelets count, MCH, and MCH concentration markers between HCV and HGV coinfected patients in comparison with HCV-infected patients.


Assuntos
Coinfecção/epidemiologia , Infecções por Flaviviridae/epidemiologia , Vírus GB C/patogenicidade , Hepatite C Crônica/epidemiologia , Hepatite Viral Humana/epidemiologia , Adulto , Coinfecção/sangue , Coinfecção/diagnóstico , Coinfecção/virologia , Índices de Eritrócitos , Feminino , Infecções por Flaviviridae/sangue , Infecções por Flaviviridae/diagnóstico , Infecções por Flaviviridae/virologia , Hepatite C Crônica/sangue , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/virologia , Hepatite Viral Humana/sangue , Hepatite Viral Humana/diagnóstico , Hepatite Viral Humana/virologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Contagem de Plaquetas , Prevalência , Carga Viral
6.
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.
Inflamm Res ; 66(6): 477-486, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28285394

RESUMO

Over the course of time, Hepatitis C has become a universal health menace. Its deleterious effects on human liver encompass a lot of physiological, genetic as well as epigenetic alterations. Fatty liver (Hepatic steatosis) is an inflammation having multifactorial ancestries; one of them is HCV (steatohepatitis). HCV boosts several cellular pathways involving up-regulation of a number of cytokines. Current study reviews the regulation of some selective key cytokines during HCV infection, to help generate an improved understanding of their role. These cytokines, IL-1ß, IL-6, TNF-α, and IFN-ϒ, are inflammatory markers of the body. These particular markers along with others help hepatocytes against viral infestation. However, recently, their association has been found in degradation of liver on the trail heading to non-alcoholic steatohepatitis (NASH). Consequently, the disturbance in their equilibrium has been repeatedly reported during HCV infection. Quite a number of findings are affirming their up-regulation. Although these cell markers are stimulated by hepatocytes as their standard protection mechanism, but modern studies have testified the paradoxical nature of this defense line. Nevertheless, direct molecular or epigenetic research is needed to question the actual molecular progressions and directions commanding liver to steatosis, cirrhosis, or eventually HCC (Hepatocellular Carcinoma).


Assuntos
Citocinas/imunologia , Hepatite C/imunologia , Fígado/imunologia , Hepatopatia Gordurosa não Alcoólica/imunologia , Animais , Hepacivirus , Humanos
8.
Virol J ; 12: 148, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26395339

RESUMO

BACKGROUND: Pattern of Dengue periodic epidemics through the years along with sporadic cases of Dengue hemorrhagic fever followed by a severe 2011 epidemic of Dengue fever in Pakistan make Pakistan a Dengue endemic country. To study the entry and evolution of dengue virus serotype 2 (DENV-2) in Pakistan, we sequenced three full length genomes and 24 complete envelope sequences of DENV-2 from the years 2010, 2011 and 2013 collected from Punjab province of Pakistan. METHODS: Phylogenetic and Bayesian phylogeographic analyses was applied to three full genome sequences as well as 24 envelope sequences to study the spatiotemporal dynamics of DENV-2 in Pakistan. RESULTS: Most of the DENV-2 viruses from the years 2008 to 2013 formed a monophyletic Pakistani clade in IVb sublineage of cosmopolitan genotype except one 2008 DENV-2 strain. Phylogeographic analysis revealed that this 2008 DENV-2 strain was rooted to India 25.4 years ago with a location probability of 0.88. However Pakistani clade rooted back to Sri Lanka 12.6 years ago with a location probability of 0.57. CONCLUSION: DENV-2 genotype IV was introduced in Pakistan in two time events. First event was introduction from India to Pakistan in the late 1980s (around 1986), and second event was introduction from Sri Lanka to Pakistan around 2000. The later introduction event was responsible for major outbreaks in the Punjab region of Pakistan, including major 2011 outbreak. After the second Introduction event, DENV-2 circulated locally in the region forming a distinct Sublineage within the IVb cosmopolitan genotype of DENV-2.


Assuntos
Vírus da Dengue/classificação , Vírus da Dengue/genética , Dengue/virologia , Surtos de Doenças , Filogeografia , Análise por Conglomerados , Dengue/epidemiologia , Vírus da Dengue/isolamento & purificação , Evolução Molecular , Genoma Viral , Humanos , Índia , Dados de Sequência Molecular , Paquistão , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência , Sri Lanka/epidemiologia
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