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1.
Water Sci Technol ; 88(3): 595-614, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37578877

RESUMO

Arsenic contamination in groundwater due to natural or anthropogenic sources is responsible for carcinogenic and non-carcinogenic risks to humans and the ecosystem. The physicochemical properties of groundwater in the study area were determined in the laboratory using the samples collected across the Varanasi region of Uttar Pradesh, India. This paper analyses the physicochemical properties of water using machine learning, descriptive statistics, geostatistical and spatial analysis. Pearson correlation was used for feature selection and highly correlated features were selected for model creation. Hydrochemical facies of the study area were analyzed and the hyperparameters of machine learning models, i.e., multilayer perceptron, random forest (RF), naïve Bayes, and decision tree were optimized before training and testing the groundwater samples as high (1) or low (0) arsenic contamination levels based on the WHO 10 µg/L guideline value. The overall performance of the models was compared based on accuracy, sensitivity, and specificity value. Among all models, the RF algorithm outclasses other classifiers, as it has a high accuracy of 92.30%, a sensitivity of 100%, and a specificity of 75%. The accuracy result was compared to prior research, and the machine learning model may be used to continually monitor the amount of arsenic pollution in groundwater.

2.
Int J Mol Sci ; 21(20)2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33050457

RESUMO

Brain-derived neurotrophic factor (BDNF) is a neuronal growth and survival factor that harbors cardioprotective qualities that may attenuate dilated cardiomyopathy. In ~30% of the population, BDNF has a common, nonsynonymous single nucleotide polymorphism rs6265 (Val66Met), which might be correlated with increased risk of cardiovascular events. We previously showed that BDNF correlates with better cardiac function in Duchenne muscular dystrophy (DMD) patients. However, the effect of the Val66Met polymorphism on cardiac function has not been determined. The goal of the current study was to determine the effects of rs6265 on BDNF biomarker suitability and DMD cardiac functions more generally. We assessed cardiovascular and skeletal muscle function in human DMD patients segregated by polymorphic allele. We also compared echocardiographic, electrophysiologic, and cardiomyocyte contractility in C57/BL-6 wild-type mice with rs6265 polymorphism and in mdx/mTR (mDMD) mouse model of DMD. In human DMD patients, plasma BDNF levels had a positive correlation with left ventricular function, opposite to that seen in rs6265 carriers. There was also a substantial decrease in skeletal muscle function in carriers compared to the Val homozygotes. Surprisingly, the opposite was true when cardiac function of DMD carriers and non-carriers were compared. On the other hand, Val66Met wild-type mice had only subtle functional differences at baseline but significantly decreased cardiomyocyte contractility. Our results indicate that the Val66Met polymorphism alters myocyte contractility, conferring worse skeletal muscle function but better cardiac function in DMD patients. Moreover, these results suggest a mechanism for the relative preservation of cardiac tissues compared to skeletal muscle in DMD patients and underscores the complexity of BDNF signaling in response to mechanical workload.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Cardiomiopatia Dilatada/etiologia , Cardiomiopatia Dilatada/metabolismo , Predisposição Genética para Doença , Miócitos Cardíacos/metabolismo , Polimorfismo de Nucleotídeo Único , Animais , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/fisiopatologia , Modelos Animais de Doenças , Ecocardiografia , Eletrocardiografia , Regulação da Expressão Gênica , Estudos de Associação Genética , Humanos , Camundongos , Camundongos Transgênicos , Contração Miocárdica
3.
J Mol Cell Cardiol ; 110: 109-120, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28756206

RESUMO

Nearly every form of the heart disease is associated with myocardial fibrosis, which is characterized by the accumulation of activated cardiac fibroblasts (CFs) and excess deposition of extracellular matrix (ECM). Although, CFs are the primary mediators of myocardial fibrosis in a diseased heart, in the traditional view, activated CFs (myofibroblasts) and resulting fibrosis were simply considered the secondary consequence of the disease, not the cause. Recent studies from our lab and others have challenged this concept by demonstrating that fibroblast activation and fibrosis are not simply the secondary consequence of a diseased heart, but are crucial for mediating various myocardial disease processes. In regards to the mechanism, the vast majority of literature is focused on the direct role of canonical SMAD-2/3-mediated TGF-ß signaling to govern the fibrogenic process. Herein, we will discuss the emerging role of the GSK-3ß, ß-catenin and TGF-ß1-SMAD-3 signaling network as a critical regulator of myocardial fibrosis in the diseased heart. The underlying molecular interactions and cross-talk among signaling pathways will be discussed. We will primarily focus on recent in vivo reports demonstrating that CF-specific genetic manipulation can lead to aberrant myocardial fibrosis and sturdy cardiac phenotype. This will allow for a better understanding of the driving role of CFs in the myocardial disease process. We will also review the specificity and limitations of the currently available genetic tools used to study myocardial fibrosis and its associated mechanisms. A better understanding of the GSK-3ß, ß-catenin and SMAD-3 signaling network may provide a novel therapeutic target for the management of myocardial fibrosis in the diseased heart.


Assuntos
Glicogênio Sintase Quinase 3 beta/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , beta Catenina/metabolismo , Animais , Fibrose , Humanos
4.
Plants (Basel) ; 10(2)2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33540497

RESUMO

The present study was aimed at exploring the effect of soil application of different concentrations of orthophosphate (P) (0, 10, 20, 30, and 40 mg kg-1) on rice agronomic and yield parameters, arsenic (As) species accumulation, and polyphenol levels in the grain of rice grown under As spiked soil (10 mg kg-1). The contents of As species (As(V), As (III), MMA and DMA) and polyphenols in rice grain samples were estimated using LC-ICP-MS and LC-MS/MS, respectively. P treatments significantly reduced the toxic effects of As on agronomic parameters such as root weight and length, shoot and spike length, straw, and grain yield. Among the treatments studied, only the treatment of 30 mg kg-1 P helps to decrease the elevated levels of As (V), As (III), and DMA in rice grains due to As application. The study revealed that 30 mg kg-1 was the optimal P application amount to minimize AS accumulation in rice grains and As-linked toxicity on agronomic parameters and chlorophyll biosynthesis. Furthermore, the levels of trans-ferulic acid, chlorogenic acid, caffeic acid, and apigenin-7-glucoside increased in response to accumulation of As in the rice grain. In conclusion, the precise use of phosphorus may help to mitigate arsenic linked phytotoxicity and enhance the food safety aspect of rice grain.

5.
Expert Opin Drug Saf ; 20(11): 1443-1450, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34259127

RESUMO

BACKGROUND: D-penicillamine (D-pen) is a copper-chelating drug and has immune-modulatory properties. D-pen is used to treat rheumatoid arthritis, Wilson's disease, and kidney stones (cystinuria). However, associated adverse events (AEs) of D-pen treatment are frequent and often serious. Therefore, a comprehensive assessment of the safety profile of D-pen is urgently needed. RESEARCH DESIGN AND METHODS: We identified and analyzed AEs associated with D-pen between April-1970 to July-2020 from the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) databases and calculated the reported odds ratio (ROR) with 95% confidence intervals (CI) using the disproportionality analysis. RESULTS: A total of 9,150,234 AEs related to drugs were reported in the FAERS database, of which 542 were related to D-Pen. We report that D-pen was associated with dystonia (ROR: 20.52; 95%CI: 12.46-33.80), drug hypersensitivity (ROR: 5.42; 95%CI: 3.72-7.90), pancytopenia (ROR: 10.20; 95%CI: 5.61-18.56), joint swelling (ROR: 9.07; 95%CI: 5.51-14.94), renal-impairment (ROR: 6.68; 95%CI: 3.67-12.15), dysphagia (ROR: 5.05; 95%CI: 2.76-8.89), aggravation of condition (ROR: 4.16; 95%CI: 2.60-6.67), congestive cardiac failure (ROR: 4.04; 95%CI: 2.22-7.35), peripheral edema (ROR: 3.77; 95%CI: 2.17-6.55), tremor (ROR: 3.46; 95%CI: 2.00-6.01), pyrexia (ROR: 3.46; 95%CI: 2.00-6.01), and gait disturbance (ROR: 2.41; 95%CI: 1.29-4.52). CONCLUSIONS: Patients taking D-pen require close monitoring of renal function, blood counts, immunity, liver, cardiac function, and neurological function. D-pen suppresses immune system which maximizes the risk of infection.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Quelantes/efeitos adversos , Penicilamina/efeitos adversos , Adolescente , Adulto , Idoso , Bases de Dados Factuais , Monitoramento de Medicamentos/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Farmacovigilância , Estudos Retrospectivos , Estados Unidos , United States Food and Drug Administration , Adulto Jovem
6.
J Pers Med ; 11(2)2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33503824

RESUMO

A tightly regulated protein quality control (PQC) system maintains a healthy balance between correctly folded and misfolded protein species. This PQC system work with the help of a complex network comprised of molecular chaperones and proteostasis. Any intruder, especially environmental pollutants, disrupt the PQC network and lead to PQCs disruption, thus generating damaged and infectious protein. These misfolded/unfolded proteins are linked to several diseases such as Parkinson's disease, Alzheimer's disease, Huntington's disease, and cataracts. Numerous studies on proteins misfolding and disruption of PQCs by environmental pollutants highlight the necessity of detailed knowledge. This review represents the PQCs network and environmental pollutants' impact on the PQC network, especially through the protein clearance system.

7.
Int J Cardiol ; 316: 214-221, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32470534

RESUMO

The advent of tyrosine kinase inhibitors (TKIs) targeted therapy revolutionized the treatment of chronic myeloid leukemia (CML) patients. However, cardiotoxicity associated with these targeted therapies puts the cancer survivors at higher risk. Ponatinib is a third-generation TKI for the treatment of CML patients having gatekeeper mutation T315I, which is resistant to the first and second generation of TKIs, namely, imatinib, nilotinib, dasatinib, and bosutinib. Multiple unbiased screening from our lab and others have identified ponatinib as most cardiotoxic FDA approved TKI among the entire FDA approved TKI family (total 50+). Indeed, ponatinib is the only treatment option for CML patients with T315I mutation. This review focusses on the cardiovascular risks and mechanism/s associated with CML TKIs with a particular focus on ponatinib cardiotoxicity. We have summarized our recent findings with transgenic zebrafish line harboring BNP luciferase activity to demonstrate the cardiotoxic potential of ponatinib. Additionally, we will review the recent discoveries reported by our and other laboratories that ponatinib primarily exerts its cardiotoxicity via an off-target effect on cardiomyocyte prosurvival signaling pathways, AKT and ERK. Finally, we will shed light on future directions for minimizing the adverse sequelae associated with CML-TKIs.


Assuntos
Antineoplásicos , Cardiotoxicidade , Animais , Antineoplásicos/efeitos adversos , Resistencia a Medicamentos Antineoplásicos , Humanos , Imidazóis , Inibidores de Proteínas Quinases/efeitos adversos , Piridazinas , Peixe-Zebra
8.
J Clin Med ; 9(6)2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32549293

RESUMO

In light of the favorable outcomes of few small, non-randomized clinical studies, the Food and Drug Administration (FDA) has issued an Emergency Use Authorization (EUA) to Hydroxychloroquine (HCQ) for hospitalized coronavirus disease 2019 (COVID-19) patients. In fact, subsequent clinical studies with COVID-19 and HCQ have reported limited efficacy and poor clinical benefits. Unfortunately, a robust clinical trial for its effectiveness is not feasible at this emergency. Additionally, HCQ was suspected of causing cardiovascular adverse reactions (CV-AEs), but it has never been directly investigated. The objective of this pharmacovigilance analysis was to determine and characterize HCQ-associated cardiovascular adverse events (CV-AEs). We performed a disproportionality analysis of HCQ-associated CV-AEs using the FDA adverse event reporting system (FAERS) database. The FAERS database, comprising more than 11,901,836 datasets and 10,668,655 patient records with drug-adverse reactions, was analyzed. The disproportionality analysis was used to calculate the reporting odds ratios (ROR) with 95% confidence intervals (CI) to predict HCQ-associated CV-AEs. HCQ was associated with higher reporting of right ventricular hypertrophy (ROR: 6.68; 95% CI: 4.02 to 11.17), left ventricular hypertrophy (ROR: 3.81; 95% CI: 2.57 to 5.66), diastolic dysfunction (ROR: 3.54; 95% CI: 2.19 to 5.71), pericarditis (ROR: 3.09; 95% CI: 2.27 to 4.23), torsades de pointes (TdP) (ROR: 3.05; 95% CI: 2.30 to 4.10), congestive cardiomyopathy (ROR: 2.98; 95% CI: 2.01 to 4.42), ejection fraction decreased (ROR: 2.41; 95% CI: 1.80 to 3.22), right ventricular failure (ROR: 2.40; 95% CI: 1.64 to 3.50), atrioventricular block complete (ROR: 2.30; 95% CI: 1.55 to 3.41) and QT prolongation (ROR: 2.09; 95% CI: 1.74 to 2.52). QT prolongation and TdP are most relevant to the COVID-19 treatment regimen of high doses for a comparatively short period and represent the most common HCQ-associated AEs. The patients receiving HCQ are at higher risk of various cardiac AEs, including QT prolongation and TdP. These findings highlight the urgent need for prospective, randomized, controlled studies to assess the risk/benefit ratio of HCQ in the COVID-19 setting before its widespread adoption as therapy.

9.
Cells ; 9(5)2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32365965

RESUMO

Obesity is an independent risk factor for cardiovascular diseases (CVD), including heart failure. Thus, there is an urgent need to understand the molecular mechanism of obesity-associated cardiac dysfunction. We recently reported the critical role of cardiomyocyte (CM) Glycogen Synthase Kinase-3 beta (GSK-3ß) in cardiac dysfunction associated with a developing obesity model (deletion of CM-GSK-3ß prior to obesity). In the present study, we investigated the role of CM-GSK-3ß in a clinically more relevant model of established obesity (deletion of CM-GSK-3ß after established obesity). CM-GSK-3ß knockout (GSK-3ßfl/flCre+/-) and controls (GSK-3ßfl/flCre-/-) mice were subjected to a high-fat diet (HFD) in order to establish obesity. After 12 weeks of HFD treatment, all mice received tamoxifen injections for five consecutive days to delete GSK-3ß specifically in CMs and continued on the HFD for a total period of 55 weeks. To our complete surprise, CM-GSK-3ß knockout (KO) animals exhibited a globally improved glucose tolerance and maintained normal cardiac function. Mechanistically, in stark contrast to the developing obesity model, deleting CM-GSK-3ß in obese animals did not adversely affect the GSK-3αS21 phosphorylation (activity) and maintained canonical ß-catenin degradation pathway and cardiac function. As several GSK-3 inhibitors are in the trial to treat various chronic conditions, including metabolic diseases, these findings have important clinical implications. Specifically, our results provide critical pre-clinical data regarding the safety of GSK-3 inhibition in obese patients.


Assuntos
Deleção de Genes , Glucose/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Testes de Função Cardíaca , Coração/fisiopatologia , Miócitos Cardíacos/enzimologia , Obesidade/enzimologia , Obesidade/fisiopatologia , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/patologia , Fenótipo , Transdução de Sinais , Remodelação Ventricular
10.
Chemosphere ; 238: 124623, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31545212

RESUMO

The Indo-Gangetic alluvium is prime region for intensive agricultural. In some areas of this region, groundwater is now becoming progressively polluted by contamination with poisonous substances like arsenic. Intensive irrigation with arsenic contaminated ground water in dry spell results in the formation of As(III) which is more toxic. Thus groundwater quality assessment of Gangetic basin has become essential for its safer use. Therefore we under took study on the spatial variability of arsenic by collecting georeferred groundwater samples on grid basis from various water sources like dug well, bore and hand pumps covering the river bank region of Ganga basin. Water quality was investigated through determination pH, EC, TDS, salinity, Na, K, Ca, Mg, SAR, SSP, CO3, HCO3, RSC, Cl, As, Fe, Zn, Mn and Cu, etc. Results pointed severe As contamination in ground water of three sites of the study area. ARC GIS software is now able to process maps along with tabular data and compare them well, to provide the spatial visualization of information and using this tool, the Geographical Information System (GIS) of arsenic was developed. It was noticed from spatial maps that concentration of arsenic was more near the meandering points of Ganga.


Assuntos
Arsênio/análise , Monitoramento Ambiental/métodos , Água Subterrânea/química , Rios/química , Poluentes Químicos da Água/análise , Geografia , Humanos , Índia , Íons , Medição de Risco , Salinidade , Poluição da Água/análise , Qualidade da Água , Abastecimento de Água/normas
11.
Cardiovasc Res ; 115(1): 20-30, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30321309

RESUMO

With an estimated 38 million current patients, heart failure (HF) is a leading cause of morbidity and mortality worldwide. Although the aetiology differs, HF is largely a disease of cardiomyocyte (CM) death or dysfunction. Due to the famously limited amount of regenerative capacity of the myocardium, the only viable option for advanced HF patients is cardiac transplantation; however, donor's hearts are in very short supply. Thus, novel regenerative strategies are urgently needed to reconstitute the injured hearts. Emerging data from our lab and others have elucidated that CM-specific deletion of glycogen synthase kinase (GSK)-3 family of kinases induces CM proliferation, and the degree of proliferation is amplified in the setting of cardiac stress. If this proliferation is sufficiently robust, one could induce meaningful regeneration without the need for delivering exogenous cells to the injured myocardium (i.e. cardiac regeneration in situ). Herein, we will discuss the emerging role of the GSK-3s in CM proliferation and differentiation, including their potential implications in cardiac regeneration. The underlying molecular interactions and cross-talk among signalling pathways will be discussed. We will also review the specificity and limitations of the available small molecule inhibitors targeting GSK-3 and their potential applications to stimulate the endogenous cardiac regenerative responses to repair the injured heart.


Assuntos
Proliferação de Células/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Insuficiência Cardíaca/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Inibidores de Proteínas Quinases/uso terapêutico , Regeneração/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Receptores ErbB/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Via de Sinalização Hippo , Humanos , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/patologia , Neuregulina-1/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais
12.
Sci Rep ; 8(1): 3719, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29487356

RESUMO

Enteropathogenic E. coli infection is characterized by rapid onset of diarrhea but the underlying mechanisms are not well defined. EPEC targets the tight junctions which selectively regulate the permeability of charged and uncharged molecules. Cooperative actions of the EPEC effectors EspF and Map have been reported to mediate tight junction disruption. To analyze the individual contributions of EspF and Map, we generated in vitro models where EspF and Map, derived from the EPEC strain E2348/69, were constitutively expressed in epithelial cells. Here we report that tight junction disruption by EspF and Map is caused by the inhibition of the junctional recruitment of proteins during tight junction assembly. Constitutive expression of EspF and Map depleted the levels of tight junction proteins. EspF down-regulated the transcript levels of claudin-1, occludin and ZO-1, while Map down-regulated only claudin-1 transcripts. Both effectors also caused lysosomal degradation of existing tight junction proteins. We also identified a novel interaction of Map with non-muscle myosin II. Consistent with earlier studies, EspF was found to interact with ZO-1 while actin was the common interacting partner for both effectors. Our data provides evidence for the distinct roles of Map and EspF in tight junction disruption through non-synergistic functions.


Assuntos
Escherichia coli Enteropatogênica/metabolismo , Proteínas de Escherichia coli/metabolismo , Junções Íntimas/metabolismo , Junções Íntimas/microbiologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular , Escherichia coli Enteropatogênica/genética , Células Epiteliais/metabolismo , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Humanos , Mucosa Intestinal/citologia , Peptídeos e Proteínas de Sinalização Intracelular
13.
Int J Cardiol ; 259: 145-152, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29398139

RESUMO

BACKGROUND AND RATIONALE: Obesity, an independent risk factor for the development of myocardial diseases is a growing healthcare problem worldwide. It's well established that GSK-3ß is critical to cardiac pathophysiology. However, the role cardiomyocyte (CM) GSK-3ß in diet-induced cardiac dysfunction is unknown. METHODS: CM-specific GSK-3ß knockout (CM-GSK-3ß-KO) and littermate controls (WT) mice were fed either a control diet (CD) or high-fat diet (HFD) for 55weeks. Cardiac function was assessed by transthoracic echocardiography. RESULTS: At baseline, body weights and cardiac function were comparable between the WT and CM-GSK-3ß-KOs. However, HFD-fed CM-GSK-3ß-KO mice developed severe cardiac dysfunction. Consistently, both heart weight/tibia length and lung weight/tibia length were significantly elevated in the HFD-fed CM-GSK-3ß-KO mice. The impaired cardiac function and adverse ventricular remodeling in the CM-GSK-3ß-KOs were independent of body weight or the lean/fat mass composition as HFD-fed CM-GSK-3ß-KO and controls demonstrated comparable body weight and body masses. At the molecular level, on a CD, CM-GSK-3α compensated for the loss of CM-GSK-3ß, as evident by significantly reduced GSK-3αs21 phosphorylation (activation) resulting in a preserved canonical ß-catenin ubiquitination pathway and cardiac function. However, this protective compensatory mechanism is lost with HFD, leading to excessive accumulation of ß-catenin in HFD-fed CM-GSK-3ß-KO hearts, resulting in adverse ventricular remodeling and cardiac dysfunction. CONCLUSION: In summary, these results suggest that cardiac GSK-3ß is crucial to protect against obesity-induced adverse ventricular remodeling and cardiac dysfunction.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Deleção de Genes , Glicogênio Sintase Quinase 3 beta/deficiência , Miócitos Cardíacos/enzimologia , Obesidade/enzimologia , Animais , Glicogênio Sintase Quinase 3 beta/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Miócitos Cardíacos/patologia , Obesidade/genética , Obesidade/patologia
14.
F1000Res ; 4: 231, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27239268

RESUMO

Enteropathogenic E. coli (EPEC) causes acute intestinal infections in infants in the developing world. Infection typically spreads through contaminated food and water and leads to severe, watery diarrhea. EPEC attaches to the intestinal epithelial cells and directly injects virulence factors which modulate multiple signaling pathways leading to host cell dysfunction. However, the molecular mechanisms that regulate the onset of diarrhea are poorly defined. A major target of EPEC is the host cell tight junction complex which acts as a barrier and regulates the passage of water and solutes through the paracellular space. In this review, we focus on the EPEC effectors that target the epithelial barrier, alter its functions and contribute to leakage through the tight junctions.

15.
Bioengineered ; 6(6): 335-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26430918

RESUMO

Enteropathogenic E. coli (EPEC) cause diarrhea and are the major cause of mortality in developing countries. EPEC use a type III secretion system to deliver effector proteins into the host epithelial cells. To understand the functions of these effectors, majority of studies on EPEC pathogenesis have relied on infections of animals or cell lines with wild type strains of EPEC or mutant strains deficient in one or more effectors. While these studies have provided valuable data, it can be difficult to assess functions of an individual effector in the presence of other EPEC effectors. Recent studies have reported the use of transient transfections with plasmids encoding various EPEC effectors into different cell lines. However, variable transfection efficiencies and expression levels of the effector proteins coupled with their expression for relatively short periods of time pose a problem if the long term effects of these effectors need to be examined. We have generated a MDCK cell line with constitutive expression of the EPEC effector Map (Mitochondrial associated protein) for efficient stable expression of EGFP-tagged Map. We observed that the constitutive expression of Map increased the permeability of charged and non-charged molecules. We also generated polyclonal antibodies against Map and checked for their specificity in MDCK-Map expressing cells. Map has been reported to contribute to the onset of diarrhea but the underlying mechanism is yet to be identified. The MDCK-Map cell line and the anti-Map antibodies generated by us can be used for in vitro studies to examine the role of Map in EPEC pathogenesis.


Assuntos
Escherichia coli Enteropatogênica/genética , Escherichia coli Enteropatogênica/patogenicidade , Proteínas de Escherichia coli/genética , Animais , Anticorpos Antibacterianos/biossíntese , Clonagem Molecular , Cães , Escherichia coli Enteropatogênica/imunologia , Proteínas de Escherichia coli/imunologia , Proteínas de Escherichia coli/metabolismo , Engenharia Genética , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Células Madin Darby de Rim Canino , Camundongos , Modelos Biológicos , Engenharia de Proteínas , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/metabolismo , Junções Íntimas/metabolismo , Transfecção , Virulência/genética
16.
Bioinformation ; 5(8): 320-5, 2011 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-21383918

RESUMO

Visceral leishmaniasis is a macrophage associated disorder which leads to a profound decrease in the natural immunotherapeutic potential of the infected subjects to combat the disease. The major surface glycoprotein gp63 has been found to be a significant vaccine candidate against visceral leishmaniasis. The current study addresses the levels of similarity and identity in the gp63 obtained from different species of Leishmania viz donovoni, chagasi and infantum linked to the cause of visceral leishmaniasis. The results from BLAST, Phylogram and Cladogram studies indicate significant identity, similarity and conservation of important residues in the protein which lead us to conclude that a common gp63 based vaccine can be used as a therapeutical tool against visceral leishmaniasis caused by different species strains of leishmania.

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