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1.
Brief Bioinform ; 22(5)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33834183

RESUMO

Minichromosome maintenance complex component 7 (MCM7) belongs to the minichromosome maintenance family that is important for the initiation of eukaryotic DNA replication. Overexpression of the MCM7 protein is relative to cellular proliferation and responsible for aggressive malignancy in various cancers. Mechanistically, inhibition of MCM7 significantly reduces the cellular proliferation associated with cancer. To date, no effective small molecular candidate has been identified that can block the progression of cancer induced by the MCM7 protein. Therefore, the study has been designed to identify small molecular-like natural drug candidates against aggressive malignancy associated with various cancers by targeting MCM7 protein. To identify potential compounds against the targeted protein a comprehensive in silico drug design including molecular docking, ADME (Absorption, Distribution, Metabolism and Excretion), toxicity, and molecular dynamics (MD) simulation approaches has been applied. Seventy phytochemicals isolated from the neem tree (Azadiractha indica) were retrieved and screened against MCM7 protein by using the molecular docking simulation method, where the top four compounds have been chosen for further evaluation based on their binding affinities. Analysis of ADME and toxicity properties reveals the efficacy and safety of the selected four compounds. To validate the stability of the protein-ligand complex structure MD simulations approach has also been performed to the protein-ligand complex structure, which confirmed the stability of the selected three compounds including CAS ID:105377-74-0, CID:12308716 and CID:10505484 to the binding site of the protein. In the study, a comprehensive data screening process has performed based on the docking, ADMET properties, and MD simulation approaches, which found a good value of the selected four compounds against the targeted MCM7 protein and indicates as a promising and effective human anticancer agent.


Assuntos
Azadirachta/química , Informática/métodos , Componente 7 do Complexo de Manutenção de Minicromossomo/antagonistas & inibidores , Simulação de Dinâmica Molecular , Neoplasias/tratamento farmacológico , Compostos Fitoquímicos/uso terapêutico , Algoritmos , Sítios de Ligação , Detecção Precoce de Câncer , Humanos , Ligantes , Componente 7 do Complexo de Manutenção de Minicromossomo/química , Componente 7 do Complexo de Manutenção de Minicromossomo/metabolismo , Simulação de Acoplamento Molecular , Terapia de Alvo Molecular/métodos , Neoplasias/diagnóstico , Neoplasias/metabolismo , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , Ligação Proteica , Domínios Proteicos , Termodinâmica
2.
Molecules ; 27(7)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35408488

RESUMO

Colorectal cancer (CRC) is the second most common cause of death worldwide, affecting approximately 1.9 million individuals in 2020. Therapeutics of the disease are not yet available and discovering a novel anticancer drug candidate against the disease is an urgent need. Thymidylate synthase (TS) is an important enzyme and prime precursor for DNA biosynthesis that catalyzes the methylation of deoxyuridine monophosphate (dUMP) to deoxythymidine monophosphate (dTMP) that has emerged as a novel drug target against the disease. Elevated expression of TS in proliferating cells promotes oncogenesis as well as CRC. Therefore, this study aimed to identify potential natural anticancer agents that can inhibit the activity of the TS protein, subsequently blocking the progression of colorectal cancer. Initially, molecular docking was implied on 63 natural compounds identified from Catharanthus roseus and Avicennia marina to evaluate their binding affinity to the desired protein. Subsequently, molecular dynamics (MD) simulation, ADME (Absorption, Distribution, Metabolism, and Excretion), toxicity, and quantum chemical-based DFT (density-functional theory) approaches were applied to evaluate the efficacy of the selected compounds. Molecular docking analysis initially identified four compounds (PubChem CID: 5281349, CID: 102004710, CID: 11969465, CID: 198912) that have better binding affinity to the target protein. The ADME and toxicity properties indicated good pharmacokinetics (PK) and toxicity ability of the selected compounds. Additionally, the quantum chemical calculation of the selected molecules found low chemical reactivity indicating the bioactivity of the drug candidate. The global descriptor and HOMO-LUMO energy gap values indicated a satisfactory and remarkable profile of the selected molecules. Furthermore, MD simulations of the compounds identified better binding stability of the compounds to the desired protein. To sum up, the phytoconstituents from two plants showed better anticancer activity against TS protein that can be further developed as an anti-CRC drug.


Assuntos
Antineoplásicos , Avicennia , Catharanthus , Neoplasias Colorretais , Antineoplásicos/química , Antineoplásicos/farmacologia , Avicennia/metabolismo , Catharanthus/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Humanos , Simulação de Acoplamento Molecular , Timidilato Sintase/metabolismo
3.
Molecules ; 26(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34443556

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) is a highly infectious zoonotic virus first reported into the human population in September 2012 on the Arabian Peninsula. The virus causes severe and often lethal respiratory illness in humans with an unusually high fatality rate. The N-terminal domain (NTD) of receptor-binding S1 subunit of coronavirus spike (S) proteins can recognize a variety of host protein and mediates entry into human host cells. Blocking the entry by targeting the S1-NTD of the virus can facilitate the development of effective antiviral drug candidates against the pathogen. Therefore, the study has been designed to identify effective antiviral drug candidates against the MERS-CoV by targeting S1-NTD. Initially, a structure-based pharmacophore model (SBPM) to the active site (AS) cavity of the S1-NTD has been generated, followed by pharmacophore-based virtual screening of 11,295 natural compounds. Hits generated through the pharmacophore-based virtual screening have re-ranked by molecular docking and further evaluated through the ADMET properties. The compounds with the best ADME and toxicity properties have been retrieved, and a quantum mechanical (QM) based density-functional theory (DFT) has been performed to optimize the geometry of the selected compounds. Three optimized natural compounds, namely Taiwanhomoflavone B (Amb23604132), 2,3-Dihydrohinokiflavone (Amb23604659), and Sophoricoside (Amb1153724), have exhibited substantial docking energy >-9.00 kcal/mol, where analysis of frontier molecular orbital (FMO) theory found the low chemical reactivity correspondence to the bioactivity of the compounds. Molecular dynamics (MD) simulation confirmed the stability of the selected natural compound to the binding site of the protein. Additionally, molecular mechanics generalized born surface area (MM/GBSA) predicted the good value of binding free energies (ΔG bind) of the compounds to the desired protein. Convincingly, all the results support the potentiality of the selected compounds as natural antiviral candidates against the MERS-CoV S1-NTD.


Assuntos
Antivirais/farmacologia , Produtos Biológicos/farmacologia , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Teoria Quântica , Antivirais/metabolismo , Produtos Biológicos/metabolismo , Domínio Catalítico , Avaliação Pré-Clínica de Medicamentos , Coronavírus da Síndrome Respiratória do Oriente Médio/metabolismo , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Interface Usuário-Computador
4.
Indian J Clin Biochem ; 34(3): 324-329, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31391723

RESUMO

The present study was carried out to evaluate the in vitro cytoprotective effects of Psidium guajava and their isolated quercetin fraction to reduce the CCl4 (carbon tetrachloride) induced toxicity in HepG2 cell lines (Hepatocellular carcinoma G2). Silymarin was used as a standard drug to compare the protective effects of plant extracts in infected cell lines. MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) assay, cell viability assay, leakage parameters [Aspartate aminotransferase (AST), Alanine aminotransferase (ALT) and Lactate dehydrogenase (LDH)], lipid peroxidation and reduced glutathione (GSH) levels were used to find out the protection of human derived HepG2 cells against CCl4-induced damage. The levels of cytotoxicity, viability and GSH were reduced. While the activities of AST, ALT, LDH and lipid peroxidation was increased in CCl4-treated groups. The treatment of P. guajava and their isolated quercetin fractions (100, 200, 300 µg/mL) decreased the elevated levels of all these parameters. The results of the present study suggest that the ethanolic extract of P. guajava leaf and their isolated quercetin fractions can able to reduce the CCl4-induced cytotoxicity in HepG2 cell lines.

5.
J Nanosci Nanotechnol ; 16(1): 40-57, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27398432

RESUMO

Nanomaterials are utilized in a wide array of end user products such as pharmaceuticals, electronics, clothes and cosmetic products. Due to its size (< 100 nm), nanoparticles have the propensity to enter through the airway and skin, making its path perilous with the potential to cause damages of varying severity. Once within the body, these particles have unconstrained access to different tissues and organs including the brain, liver, and kidney. As a result, nanomaterials may cause the perturbation of the immune system eliciting an inflammatory response and cytotoxicity. This potential role is dependent on many factors such as the characteristics of the nanomaterials, presence or absence of diseases, and genetic predisposition. Cobalt and nickel nanoparticles, for example, were shown to have inflammogenic properties, while silver nanoparticles were shown to reduce allergic inflammation. Just as asbestos fibers, carbon nanotubes were shown to cause lungs damage. Some nanomaterials were shown, based on animal studies, to result in cell damage, leading to the formation of pre-cancerous lesions. This review highlights the impact of nanomaterials on immune system and its effect on human health with toxicity consideration. It recommends the development of suitable animal models to study the toxicity and bio-clearance of nanomaterials and propose safety guidelines.


Assuntos
Imunidade Adaptativa/efeitos dos fármacos , Amianto/efeitos adversos , Lesão Pulmonar/imunologia , Nanopartículas Metálicas/efeitos adversos , Metais/efeitos adversos , Nanotubos de Carbono/efeitos adversos , Animais , Citotoxinas/efeitos adversos , Humanos , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/patologia
6.
J Nanosci Nanotechnol ; 15(1): 41-53, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26328304

RESUMO

Vaccination has led to the eradication of those diseases which had once claimed millions of lives worldwide; however, it is accompanied with a number of dis-advantages especially safety issues until the entry of DNA vaccines. The DNA vaccines have been emerged as the best remedy for problematic diseases being capable of producing humoral and cellular immune responses as well as the safest vaccines so far. However, the magnitude of immune responses produced in primates is lower than that in experimental animals. There are several reasons described theoretically for this limited efficacy and a number of novel approaches have been applied to boost their immune responses, e.g., use of more efficient promoters and coding optimization, addition of traditional or genetic adjuvants, electroporation, intradermal delivery and various prime-boost strategies. One of these strategies is controlled antigen administration of plasmid DNA through microspheres and nanoparticles. This approach is accompanied with a number of advantages to overcome the limitations of traditional delivery systems in terms of stability, solubility and pharmacology. Furthermore, the surface structure of a virus highly resembles with a nanoparticle because of their geometrical regularities and nanoscale dimensions; therefore, the engineering of nanoparticles is based upon principles of natural virus attack which will be the best tool for vaccination. There is evidence that these immune responses can be augmented by properly structured nanosized particles (nanoparticles) that may avoid DNA degradation and facilitate targeted delivery to antigen presenting cells. Adsorption, formulation or encapsulation with particles has been found to stabilize DNA formulations. The use of nanoparticles for DNA vaccine delivery is a platform technology and has been applied for delivery of a variety of existing and potential vaccines successfully.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas , Vacinas de DNA , Animais , Pesquisa Biomédica , Humanos , Camundongos , Plasmídeos
7.
Mediators Inflamm ; 2014: 502749, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25258478

RESUMO

Obesity today stands at the intersection between inflammation and metabolic disorders causing an aberration of immune activity, and resulting in increased risk for diabetes, atherosclerosis, fatty liver, and pulmonary inflammation to name a few. Increases in mortality and morbidity in obesity related inflammation have initiated studies to explore different lipid mediated molecular pathways of attempting resolution that uncover newer therapeutic opportunities of anti-inflammatory components. Majorly the thromboxanes, prostaglandins, leukotrienes, lipoxins, and so forth form the group of lipid mediators influencing inflammation. Of special mention are the omega-6 and omega-3 fatty acids that regulate inflammatory mediators of interest in hepatocytes and adipocytes via the cyclooxygenase and lipoxygenase pathways. They also exhibit profound effects on eicosanoid production. The inflammatory cyclooxygenase pathway arising from arachidonic acid is a critical step in the progression of inflammatory responses. New oxygenated products of omega-3 metabolism, namely, resolvins and protectins, behave as endogenous mediators exhibiting powerful anti-inflammatory and immune-regulatory actions via the peroxisome proliferator-activated receptors (PPARs) and G protein coupled receptors (GPCRs). In this review we attempt to discuss the complex pathways and links between obesity and inflammation particularly in relation to different lipid mediators.


Assuntos
Inflamação/metabolismo , Lipídeos , Obesidade/metabolismo , Animais , Ácido Araquidônico/metabolismo , Masculino , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Ratos , Ratos Wistar
8.
J Basic Microbiol ; 54(6): 531-41, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23686910

RESUMO

Citrobacter freundii is a worldwide emerging nosocomial pathogen with escalating incidence of multidrug resistance. Citrobacter freundii exists in natural environment, especially in health care settings and is difficult to eradicate. Phage therapy is considered as an alternative way of controlling bacterial infections and contaminations. In this study, we have described isolation and characterization of a virulent bacteriophage LK1 capable of specifically infecting Citrobacter freundii. A virulent bacteriophage LK1, specific for Citrobacter freundii was isolated from sewage water sample. TEM showed that phage Lk1 has an icosahedral head 70 nm in diameter and short tail of 17 nm, and can be classified as a member of the Podoviridae family. Restriction analysis indicated that phage LK1 was a dsDNA virus with an approximate genome size of 20-23 kb. Proteomic pattern generated by SDS PAGE using purified LK1 phage particles, revealed three major and six minor protein bands with molecular weight ranging from 25 to 80 kDa. Adsorption rate of LK1 relative to the host bacterium was also determined which showed significant improvement in adsorption with the addition of CaCl2 . In a single step growth experiment, LK1 exhibited a latent period of 24 min and burst size of 801 particle/cell. Moreover, pH and thermal stability of phage LK1 demonstrated a pH range of 5.0-6.0 and phage viability decreased to 0% at 65 °C. When LK1 was used to infect six other clinically isolated pathogenic strains, it showed relatively narrow host range. LK1 was capable of eliciting efficient lysis of Citrobacter freundii, revealing its potential as a non-toxic sanitizer for controlling Citrobacter freundii infection and contamination in both hospital and other public environments.


Assuntos
Bacteriófagos/isolamento & purificação , Citrobacter freundii/virologia , Vírus de DNA/isolamento & purificação , DNA Viral/química , Podoviridae/isolamento & purificação , Esgotos/virologia , Bacteriófagos/genética , Bacteriófagos/fisiologia , Bacteriófagos/ultraestrutura , Cloreto de Cálcio/metabolismo , Vírus de DNA/química , Vírus de DNA/genética , Vírus de DNA/ultraestrutura , DNA Viral/genética , Eletroforese em Gel de Poliacrilamida , Genoma Viral , Especificidade de Hospedeiro , Concentração de Íons de Hidrogênio , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/efeitos da radiação , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Peso Molecular , Podoviridae/química , Podoviridae/genética , Podoviridae/ultraestrutura , Análise de Sequência de DNA , Temperatura , Proteínas Virais/química , Proteínas Virais/isolamento & purificação , Vírion/ultraestrutura , Ligação Viral/efeitos dos fármacos
9.
J Infect Dis ; 208(11): 1888-97, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23908491

RESUMO

BACKGROUND: The envelope glycoprotein E2 of hepatitis C virus (HCV) contains several hypervariable regions. Interestingly, 2 regions of intragenotypic hypervariability within E2 have been described as being specific to HCV subtype 3a. Based on their amino acid position in E2, they were named HVR495 and HVR575. Here, we further investigated these regions in order to better understand their role in HCV infection. METHODS: Sequences of HCV envelope glycoproteins from Pakistani patients infected with subtype 3a were cloned and compared with other subtype 3a sequences. The entry functions and the sensitivity to antibody neutralization of selected HCV glycoprotein sequences were tested in the HCV pseudotyped particles (HCVpp) system. In addition, the cell-cultured HCV system (HCVcc) was also used to confirm some of the data obtained with the HCVpp system. RESULTS: We observed interesting new features within HVR495 and HVR575 for several subtype 3a isolates. Indeed, changes in glycosylation sites were observed with the appearance of a new glycosylation site within HVR495. Importantly, HCVpp and HCVcc that contained this new HVR495 glycosylation site were less sensitive to antibody neutralization. CONCLUSIONS: We identified a new glycosylation site within the HVR495 region of HCV subtype 3a that has a protective effect against antibody neutralization.


Assuntos
Anticorpos Neutralizantes/imunologia , Epitopos/imunologia , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/imunologia , Hepatite C/virologia , Proteínas do Envelope Viral/química , Sequência de Aminoácidos , Anticorpos Monoclonais/imunologia , Linhagem Celular , Glicosilação , Hepacivirus/genética , Hepacivirus/metabolismo , Hepatite C/imunologia , Humanos , Mutação , Paquistão , RNA Viral/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Tetraspanina 28/imunologia , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/metabolismo
10.
J Taibah Univ Med Sci ; 19(3): 619-627, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38812724

RESUMO

Background: Lymphoma ranks fifth in prevalence among common cancer types worldwide. This lymphatic system cancer arises from T or B cells. Diffuse large B cell lymphomas (DLBCLs) are associated with most non-Hodgkin lymphomas. Non-coding microRNAs (miRNAs) greatly affect gene expression. A single miRNA can target numerous genes, thus largely influencing gene expression networks. MiRNAs can act as oncogenes or tumor suppressors in controlling DLBCL progression. This study investigated the roles of miRNAs in patients with DLBCL through next-generation sequencing, which was found to be sensitive, accurate, and robust. Methods: The study involved seven patients with DLBCLs and three controls at a hematology-oncology clinic. MiRNA was extracted from existing formalin-fixed, paraffin-embedded (FFPE) tissue specimens. Illumina next-generation sequencing was used to sequence samples for miRNA profiling. Results: Samples from patients showed expression of various hsa-mir miRNAs (1248, 3607, 21, 142, 1244, 182, 6516, 766, 1291, 4449, and 181a), whereas those from healthy individuals showed expression of hsa-mir 1248, 3607, 21, 142, and 877. Hsa-mir-877-3p is known to target multiple genes, and miRNAs such as hsa-mir-877-3p, hsa-mir-1291, and hsa-mir-181a-5p interact primarily with target genes. Conclusions: MiRNA profiling in FFPE tissues from patients with DLBCL suggested that miRNA levels can distinguish patients with DLBCL from controls, and therefore may provide prognostic or diagnostic biomarkers for DLBCL. Altered genes and miRNAs may also be potential therapeutic targets.

11.
J Biol Chem ; 287(44): 37340-51, 2012 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-22955269

RESUMO

Chronic hepatitis C virus (HCV) infection greatly increases the risk for type 2 diabetes and nonalcoholic steatohepatitis; however, the pathogenic mechanisms remain incompletely understood. Here we report gluconeogenic enzyme phosphoenolpyruvate carboxykinase (PEPCK) transcription and associated transcription factors are dramatically up-regulated in Huh.8 cells, which stably express an HCV subgenome replicon. HCV increased activation of cAMP response element-binding protein (CREB), CCAAT/enhancer-binding protein (C/EBPß), forkhead box protein O1 (FOXO1), and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) and involved activation of the cAMP response element in the PEPCK promoter. Infection with dominant-negative CREB or C/EBPß-shRNA significantly reduced or normalized PEPCK expression, with no change in PGC-1α or FOXO1 levels. Notably, expression of HCV nonstructural component NS5A in Huh7 or primary hepatocytes stimulated PEPCK gene expression and glucose output in HepG2 cells, whereas a deletion in NS5A reduced PEPCK expression and lowered cellular lipids but was without effect on insulin resistance, as demonstrated by the inability of insulin to stimulate mobilization of a pool of insulin-responsive vesicles to the plasma membrane. HCV-replicating cells demonstrated increases in cellular lipids with insulin resistance at the level of the insulin receptor, increased insulin receptor substrate 1 (Ser-312), and decreased Akt (Ser-473) activation in response to insulin. C/EBPß-RNAi normalized lipogenic genes sterol regulatory element-binding protein-1c, peroxisome proliferator-activated receptor γ, and liver X receptor α but was unable to reduce accumulation of triglycerides in Huh.8 cells or reverse the increase in ApoB expression, suggesting a role for increased lipid retention in steatotic hepatocytes. Collectively, these data reveal an important role of NS5A, C/EBPß, and pCREB in promoting HCV-induced gluconeogenic gene expression and suggest that increased C/EBPß and NS5A may be essential components leading to increased gluconeogenesis associated with HCV infection.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/fisiologia , Fígado Gorduroso/virologia , Genoma Viral , Hepacivirus/genética , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Proteínas não Estruturais Virais/fisiologia , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Linhagem Celular Tumoral , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Diabetes Mellitus Tipo 2/virologia , Indução Enzimática , Fígado Gorduroso/enzimologia , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Genes Reporter , Gluconeogênese/genética , Glucose/metabolismo , Glucose-6-Fosfatase/genética , Glucose-6-Fosfatase/metabolismo , Hepacivirus/fisiologia , Humanos , Insulina/fisiologia , Metabolismo dos Lipídeos/genética , Luciferases/biossíntese , Luciferases/genética , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Regiões Promotoras Genéticas , Ratos , Vesículas Secretórias/metabolismo , Transdução de Sinais , Replicação Viral
12.
Virol J ; 10: 251, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23923986

RESUMO

The disproportionate imbalance between the systemic manifestation of reactive oxygen species and body's ability to detoxify the reactive intermediates is referred to as oxidative stress. Several biological processes as well as infectious agents, physiological or environmental stress, and perturbed antioxidant response can promote oxidative stress. Oxidative stress usually happens when cells are exposed to more electrically charged reactive oxygen species (ROS) such as H2O2 or O2-. The cells' ability to handle such pro-oxidant species is impeded by viral infections particularly within liver that plays an important role in metabolism and detoxification of harmful substances. During liver diseases (such as hepatocellular or cholestatic problems), the produced ROS are involved in transcriptional activation of a large number of cytokines and growth factors, and continued production of ROS and Reactive Nitrogen Species (RNS) feed into the vicious cycle. Many human viruses like HCV are evolved to manipulate this delicate pro- and antioxidant balance; thus generating the sustainable oxidative stress that not only causes hepatic damage but also stimulates the processes to reduce treatment of damage. In this review article, the oxidant and antioxidant pathways that are perturbed by HCV genes are discussed. In the first line of risk, the pathways of lipid metabolism present a clear danger in accumulation of viral induced ROS. Viral infection leads to decrease in cellular concentrations of glutathione (GSH) resulting in oxidation of important components of cells such as proteins, DNA and lipids as well as double strand breakage of DNA. These disorders have the tendency to lead the cells toward cirrhosis and hepatocellular carcinoma in adults due to constant insult. We have highlighted the importance of such pathways and revealed differences in the extent of oxidative stress caused by HCV infection.


Assuntos
Hepacivirus/fisiologia , Interações Hospedeiro-Patógeno , Fígado/patologia , Fígado/virologia , Estresse Oxidativo , Espécies Reativas de Oxigênio/toxicidade , Humanos , Espécies Reativas de Oxigênio/metabolismo
13.
Pak J Pharm Sci ; 26(6): 1181-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24191324

RESUMO

Interferon Lambda (IFN-λ) is a type III interferon which belongs to a novel family of cytokines and possesses antiviral and antitumor properties. It is unique in its own class of cytokines; because of the specificity towards its heterodimer receptors and its structural similarities with cytokines of other classes. This renders IFN-λ a better choice for the treatment against many diseases including viral hepatitis and human coronavirus (HCoV-EMC). The present study describes a computational approach known as relative synonymous codon usage (RSCU); used to enhance the expression of IFN-λ protein in a eukaryotic expression system. Manually designed and commercially synthesized IFN-λ gene was cloned into pET-22b expression plasmid under the control of inducible T7-lac promoter. Maximum levels of IFN-λ expression was observed with 0.4 mM IPTG in transformed E. coli incubated for 4 hours in LB medium. Higher concentrations of IPTG had no or negative effect on the expression of IFN-λ. This synthetically over expressed IFN-λ can be tested as a targeted treatment option for viral hepatitis after purification.


Assuntos
Códon , Escherichia coli/genética , Genes Sintéticos , Interferons/genética , Clonagem Molecular , Expressão Gênica
14.
Antibiotics (Basel) ; 12(3)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36978364

RESUMO

Carbapenem-resistant Pseudomonas aeruginosa (CRPA) poses a serious public health threat in multiple clinical settings. In this study, we detail the isolation of a lytic bacteriophage, vB_PseuP-SA22, from wastewater using a clinical strain of CRPA. Transmission electron microscopy (TEM) analysis identified that the phage had a podovirus morphology, which agreed with the results of whole genome sequencing. BLASTn search allowed us to classify vB_PseuP-SA22 into the genus Bruynoghevirus. The genome of vB_PseuP-SA22 consisted of 45,458 bp of double-stranded DNA, with a GC content of 52.5%. Of all the open reading frames (ORFs), only 26 (44.8%) were predicted to encode certain functional proteins, whereas the remaining 32 (55.2%) ORFs were annotated as sequences coding functionally uncharacterized hypothetical proteins. The genome lacked genes coding for toxins or markers of lysogenic phages, including integrases, repressors, recombinases, or excisionases. The phage produced round, halo plaques with a diameter of 1.5 ± 2.5 mm on the bacterial lawn. The TEM revealed that vB_PseuP-SA22 has an icosahedral head of 57.5 ± 4.5 nm in length and a short, non-contractile tail (19.5 ± 1.4 nm). The phage showed a latent period of 30 min, a burst size of 300 PFU/infected cells, and a broad host range. vB_PseuP-SA22 was found to be stable between 4-60 °C for 1 h, while the viability of the virus was reduced at temperatures above 60 °C. The phage showed stability at pH levels between 5 and 11. vB_PauP-SA22 reduced the number of live bacteria in P. aeruginosa biofilm by almost five logs. The overall results indicated that the isolated phage could be a candidate to control CRPA infections. However, experimental in vivo studies are essential to ensure the safety and efficacy of vB_PauP-SA22 before its use in humans.

15.
Antibiotics (Basel) ; 12(2)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36830292

RESUMO

Bacteria and their predators, bacteriophages, or phages are continuously engaged in an arms race for their survival using various defense strategies. Several studies indicated that the bacterial immune arsenal towards phage is quite diverse and uses different components of the host machinery. Most studied antiphage systems are associated with phages, whose genomic matter is double-stranded-DNA. These defense mechanisms are mainly related to either the host or phage-derived proteins and other associated structures and biomolecules. Some of these strategies include DNA restriction-modification (R-M), spontaneous mutations, blocking of phage receptors, production of competitive inhibitors and extracellular matrix which prevent the entry of phage DNA into the host cytoplasm, assembly interference, abortive infection, toxin-antitoxin systems, bacterial retrons, and secondary metabolite-based replication interference. On the contrary, phages develop anti-phage resistance defense mechanisms in consortium with each of these bacterial phage resistance strategies with small fitness cost. These mechanisms allow phages to undergo their replication safely inside their bacterial host's cytoplasm and be able to produce viable, competent, and immunologically endured progeny virions for the next generation. In this review, we highlight the major bacterial defense systems developed against their predators and some of the phage counterstrategies and suggest potential research directions.

16.
Pathogens ; 12(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36678446

RESUMO

Ticks and tick-borne diseases are considered a major challenge for human and animal health in tropical, sub-tropical, and temperate regions of the world. However, only scarce information is available on the characterization of tick species infesting dogs in Pakistan. In this study, we present a comprehensive report on the epidemiological and phylogenetic aspects of ticks infesting dogs in Pakistan using the mitochondrial markers i.e. Cytochrome c oxidase subunit 1 (cox1) and 16S ribosomal RNA (16S rRNA) nucleotide sequences. A total of 300 dogs were examined and 1150 ixodid ticks were collected across central Khyber Pakhtunkhwa, Pakistan. The morpho-molecular characterization of hard ticks revealed the presence of two ixodid tick genera on dogs, i.e., Hyalomma and Rhipicephalus, including six tick species viz. Hyalomma dromedarii (15.9%), Hyalomma excavatum (3%), Rhipicephalus sanguineus s.l. (41.3%), Rhipicephalus turanicus s.s. (28.7%), Rhipicephalus haemaphysaloides (10.2%), and Rhipicephalus microplus (2%). The total prevalence of tick infestation in dogs was 61%. The district with the highest tick prevalence rate in dogs was Mardan (14.7%), followed by Peshawar (13%), Swabi (12%), Charsadda (11%), and Malakand (10.3%), respectively. Risk factors analysis indicated that some demographic and host management-associated factors such as host age, breed, exposure to acaricides treatment, and previous tick infestation history were associated with a higher risk of tick infestation on dogs. This is the first molecular report confirming the infestation of Hyalomma and Rhipicephalus tick species in the dog population from the study area. The present study also reported a new tick−host association between Hy. excavatum, Hy. dromedarii, and dogs. Phylogenetic analysis revealed that cox1 partial nucleotide sequences of Hy. excavatum in our dataset were 100% identical to similar tick specimens identified in Turkey, and those of Hy. dromedarii were identical to tick specimens from Iran. Whereas, Rh. haemaphysaloides and Rh. microplus' cox1 partial nucleotide sequences were identical to sequences previously published from Pakistan. Rhipicephalus turanicus s.s. 's cox1 isolates from the present study were 99.8−100% identical to Pakistani-reported isolates, and those of Rh. sanguineus s.l. were 100% identical to Chinese specimens. Results on the genetic characterization of ticks were further confirmed by 16S rRNA partial nucleotide sequences analysis, which revealed 100% identity between the tick isolates of this study and those of Hy. excavatum reported from Turkey; Hy. dromedarii specimens reported from Senegal; Rh. haemaphysaloides, Rh. microplus, and Rh. turanicus s.s., previously published from Pakistan, and Rh. sanguineus s.l., published from China. Furthermore, phylogenetic analysis showed that the Rh. sanguineus s.l. isolates of this study clustered with specimens of the tropical lineage with 7.7−10% nucleotide divergence from the specimens of the temperate lineage. Further molecular works need to be performed throughout Pakistan to present a more detailed map of tick distribution with information about dog host associations, biological characteristics, and pathogen competence.

17.
Biotechnol Genet Eng Rev ; : 1-29, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36927397

RESUMO

Phage therapy has recently attracted a great deal of attention to counteract the rapid emergence of antibiotic-resistant bacteria. In comparison to monophage therapy, phage cocktails are typically used to treat individual and/or multi-bacterial infections since the bacterial agents are unlikely to become resistant as a result of exposure to multiple phages simultaneously. The bacteriolytic effect of phage cocktails may produce efficient killing effect in comparison to individual phage. However, multiple use of phages (complex cocktails) may lead to undesirable side effects such as dysbiosis, horizontal gene transfer, phage resistance, cross resistance, and/or higher cost of production. Cocktail formulation, therefore, representa compromise between limiting the complexity of the cocktail and achieving substantial bacterial load reduction towards the targeted host organisms. Despite some constraints, the applications of monophage therapy have been well documented in the literature. However, phage cocktails-based approaches and their role for the control of pathogens have not been well investigated. In this review, we discuss the principle of phage cocktail formulations, their optimization strategies, major phage cocktail preparations, and their efficacy in inactivating various food borne bacterial pathogens.

18.
Diagnostics (Basel) ; 13(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36900005

RESUMO

A wide range of histological as well as clinical properties are exhibited by B-cell non-Hodgkin's lymphomas. These properties could make the diagnostics process complicated. The diagnosis of lymphomas at an initial stage is essential because early remedial actions taken against destructive subtypes are commonly deliberated as successful and restorative. Therefore, better protective action is needed to improve the condition of those patients who are extensively affected by cancer when diagnosed for the first time. The development of new and efficient methods for early detection of cancer has become crucial nowadays. Biomarkers are urgently needed for diagnosing B-cell non-Hodgkin's lymphoma and assessing the severity of the disease and its prognosis. New possibilities are now open for diagnosing cancer with the help of metabolomics. The study of all the metabolites synthesised in the human body is called "metabolomics." A patient's phenotype is directly linked with metabolomics, which can help in providing some clinically beneficial biomarkers and is applied in the diagnostics of B-cell non-Hodgkin's lymphoma. In cancer research, it can analyse the cancerous metabolome to identify the metabolic biomarkers. This review provides an understanding of B-cell non-Hodgkin's lymphoma metabolism and its applications in medical diagnostics. A description of the workflow based on metabolomics is also provided, along with the benefits and drawbacks of various techniques. The use of predictive metabolic biomarkers for the diagnosis and prognosis of B-cell non-Hodgkin's lymphoma is also explored. Thus, we can say that abnormalities related to metabolic processes can occur in a vast range of B-cell non-Hodgkin's lymphomas. The metabolic biomarkers could only be discovered and identified as innovative therapeutic objects if we explored and researched them. In the near future, the innovations involving metabolomics could prove fruitful for predicting outcomes and bringing out novel remedial approaches.

19.
Virol J ; 9: 9, 2012 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-22234269

RESUMO

Recently it has been recognized that bacteriophages, the natural predators of bacteria can be used efficiently in modern biotechnology. They have been proposed as alternatives to antibiotics for many antibiotic resistant bacterial strains. Phages can be used as biocontrol agents in agriculture and petroleum industry. Moreover phages are used as vehicles for vaccines both DNA and protein, for the detection of pathogenic bacterial strain, as display system for many proteins and antibodies. Bacteriophages are diverse group of viruses which are easily manipulated and therefore they have potential uses in biotechnology, research, and therapeutics. The aim of this review article is to enable the wide range of researchers, scientists, and biotechnologist who are putting phages into practice, to accelerate the progress and development in the field of biotechnology.


Assuntos
Bactérias/virologia , Bacteriófagos/fisiologia , Biotecnologia/métodos , Animais , Antibacterianos , Bacteriófagos/genética , Agentes de Controle Biológico , Humanos , Vacinas
20.
Virol J ; 9: 229, 2012 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-23039269

RESUMO

BACKGROUND: Transgender males are at high risk for sexually transmitted diseases including AIDS caused by the notorious Human Immunodeficiency Virus (HIV), yet little consideration is given by the policy makers, researchers and non-governmental organizations (NGOs) towards this sensitive issue in Pakistan. METHODS: In this study, we have investigated the prevalence of HIV infection among 306 transgender males with a median age of 29 years (range 15-64 years) residing in Rawalpindi, Pakistan. Rapid HIV antibody-screening methods including the strip test and Enzyme Linked Immuno-absorbent tests were employed to detect HIV antibodies among the subjects. For further confirmation, Polymerase Chain Reaction (PCR) was carried out. Statistical analytical techniques utilized included logistic regression and chi-square. RESULTS: HIV-1 was found to be the predominant viral subtype. PCR confirmed 21.6% (Confidence Interval 0.17-0.26) of the respondents were reported being HIV positive. 15.7% of the transgender men who shave at home and 13.7% of the transgender men who were educated below 5th grade were found to have HIV. CONCLUSION: This study shows a very high prevalence of HIV among transgender males. Unawareness among these individuals about the ramifications of this infection owes largely to lack of education. The spread rate is alarming and HIV epidemic is imminent if awareness is not widespread.


Assuntos
Infecções por HIV/epidemiologia , HIV-1/isolamento & purificação , Pessoas Transgênero , Adolescente , Adulto , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Anticorpos Anti-HIV/sangue , Infecções por HIV/virologia , HIV-1/genética , HIV-1/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Reação em Cadeia da Polimerase , RNA Viral/genética , Adulto Jovem
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