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We investigated antibiotic resistance pattern in clinical bacterial pathogens isolated from in-patients and out-patients, and compared it with non-clinical bacterial isolates. 475 bacterial strains isolated from patients were examined for antibiotic resistance. Staphylococcus spp. (148; 31.1%) were found to be the most prevalent, followed by Klebsiella pneumoniae (135; 28.4%), Escherichia coli (74; 15.5%), Pseudomonas aeruginosa (65; 13.6%), Enterobacter spp. (28; 5.8%), and Acinetobacter spp. (25; 5.2%). Drug-resistant bacteria isolated were extended spectrum-ß-lactamase K. pneumoniae (8.8%), E. coli (20%), metallo-ß-lactamase P. aeruginosa (14; 2.9%), erythromycin-inducing clindamycin resistant (7.4%), and methicillin-resistant Staphylococcus species (21.6%). Pathogens belonging to the Enterobacteriaceae family were observed to undergo directional selection developing resistance against antibiotics ciprofloxacin, piperacillin-tazobactam, cefepime, and cefuroxime. Pathogens in the surgical ward exhibited higher levels of antibiotic resistance, while non-clinical P. aeruginosa and K. pneumoniae strains were more antibiotic-susceptible. Our research assisted in identifying the drugs that can be used to control infections caused by antimicrobial resistant bacteria in the population and in monitoring the prevalence of drug-resistant bacterial pathogens.
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Lactobacillus rhamnosus strain LR231 was isolated from the feces of healthy human subjects. It is observed to be a potential probiotic strain, having a broad spectrum of antimicrobial activity against a wide range of human pathogens and food pathogens. Here, we provide the 2.59-Mb draft genome sequence of L. rhamnosus LR231.
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Bacillus safensis strain VK was isolated from the rhizosphere of a cumin plant growing in the saline desert of Radhanpar, Gujarat, India. Here, we provide the 3.68-Mb draft genome sequence of B. safensis VK, which might provide information about the salt tolerance and genes encoding enzymes for the strain's plant growth-promoting potential.
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Glutamine: fructose-6-phosphate amidotransferase (GFAT), also termed GFPT1 and GFAT1, catalyzes the first committed step of the hexosamine biosynthesis pathway in mammals and consequently plays an important role in type 2 diabetes. In the present study, a combination of pharmacophore modelling, homology modelling, and molecular docking analysis was performed to design new glutamine competitive inhibitors of human GFAT, and to investigate important interaction details of inhibitor molecules. A pharmacophore model of GFAT inhibitors was developed, subsequently validated, and utilized for the screening by the PHASE database to identify new molecules. Afterwards, homology modelling was performed to construct the glutamine-binding site of the GFAT protein. The modelled active site was utilized to dock the studied molecules to investigate important receptor-ligand interactions and to scrutinize database-screened molecules on the basis of essential interactions. This systematic in silico protocol helped us to identify new molecules that would be explored for the treatment of type 2 diabetes and its complications.
Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/antagonistas & inibidores , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/química , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Simulação de Acoplamento Molecular , Animais , Domínio Catalítico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Conformação ProteicaRESUMO
Colorectal Cancer (CRC) is the second leading cause of cancer-related mortality and is the fourth most common malignant neoplasm in USA. Escaping apoptosis and cell mutation are the prime hallmarks of cancer. It is apparent that balancing the network between DNA damage and DNA repair is critical in preventing carcinogenesis. One-third of cancers might be prevented by nutritious healthy diet, maintaining healthy weight and physical activity. In this review, an attempt is made to abridge the role of carcinogen in colorectal cancer establishment and prognosis, where special attention has been paid to food-borne mutagens and functional role of beneficial human gut microbiome in evading cancer. Further the significance of tailor-made prebiotics, probiotics and synbiotics in cancer management by bio-antimutagenic and desmutagenic activity has been elaborated. Probiotic bacteria are live microorganisms that, when administered in adequate amounts, confer a healthy benefit on the host. Prebiotics are a selectively fermentable non-digestible oligosaccharide or ingredient that brings specific changes, both in the composition and/or activity of the gastrointestinal microflora, conferring health benefits. Synbiotics are a combination of probiotic bacteria and the growth promoting prebiotic ingredients that purport "synergism."
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Neoplasias Colorretais/terapia , Prebióticos , Probióticos/administração & dosagem , Simbióticos , Antimutagênicos/administração & dosagem , Trato Gastrointestinal/microbiologia , Humanos , Fatores Imunológicos/administração & dosagem , Metagenoma , Estados UnidosRESUMO
The protective effect of Lactobacillus rhamnosus 231 (Lr 231) against potent carcinogen N-Methyl-N'-Nitro-N-Nitrosoguanidine (MNNG) in the rat model is studied. Daily feeding with Lr 231 improved the body weight of male Wistar rats compared with control groups. Fecal azoreductase (p < 0.001) and nitroreductase (p < 0.01) enzyme activity decreased significantly in Lr 231 group in comparison with control groups that received only phosphate buffer or MNNG. Oral administration of MNNG led to a significant increase in Glutathione transferase (GST) while Glutathione reductase (GSH) showed decreased activity. Conversely, feeding Lr 231 showed significantly increased GSH and decreased GST activity in comparison to the MNNG group, emphasizing the protection provided by Lr 231 against MNNG. Histopathological analysis of liver, spleen and colon showed decreased signs of inflammation in the Lr 231 group. The present study highlights that inclusion of active Lr 231 in regular diets could be used to prevent MNNG induced colon carcinoma.
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Inflamação/terapia , Lacticaseibacillus rhamnosus/metabolismo , Metilnitronitrosoguanidina/efeitos adversos , Probióticos/uso terapêutico , Animais , Peso Corporal , Colo/enzimologia , Colo/patologia , Ativação Enzimática , Ensaios Enzimáticos , Fezes/enzimologia , Glutationa Transferase/metabolismo , Inflamação/induzido quimicamente , Inflamação/patologia , Fígado/enzimologia , Fígado/patologia , Masculino , NADH NADPH Oxirredutases/metabolismo , Nitrorredutases , Probióticos/administração & dosagem , Probióticos/metabolismo , Ratos , Ratos Wistar , Baço/enzimologia , Baço/patologiaRESUMO
In vitro mutagen binding ability of human Lactobacillus rhamnosus 231 (Lr 231) was evaluated against acridine orange (AO), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), 2-amino-3, 8-dimethylimidazo-[4,5-f]-quinoxaline (MeIQx) and 4-nitro-o-phenylenediamine (NPD). Binding of AO by Lr 231 is due to adsorption, thereby leading to removal of mutagen in solution and is instantaneous, pH- and concentration-dependent. Whereas, binding of MNNG and MeIQx by Lr 231 results into biotransformation leading to detoxification with subsequent loss of mutagenicity as determined by spectral analysis, thin layer chromatography and Ames test. Binding of mutagen by Lr 231 was dependent on culture age and optimum binding of AO, MNNG and MeIQx was observed to occur with 24 h old culture. Cells of Lr 231 were subjected to different chemical treatments prior to binding studies. Results indicated cell wall component such as cell wall polysaccharide, peptidoglycan, carbohydrates and proteins plays an important role in adsorption of AO, also involving hydrophilic and ionic interactions. Binding, biotransformation and detoxification of MNNG and MeIQx by Lr 231 was dependent on cell surface characteristics mainly involving carbohydrates, proteins, teichoic acid/lipoteichoic acid, hydrophobic interaction and presence of thiol group. L. rhamnosus 231 bound MNNG instantaneously. More than 96 (p < 0.01) and 70% (p < 0.05) cells remained viable after mutagen binding and various pretreatments respectively. This study shows Lr 231 exhibits ability to bind and detoxify potent mutagens, and this property can be useful in formulating fermented foods for removal of potent mutagens.
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Antimutagênicos , Lacticaseibacillus rhamnosus/metabolismo , Mutagênicos/metabolismo , Laranja de Acridina/química , Laranja de Acridina/metabolismo , Biotransformação , Meios de Cultura , Fezes/microbiologia , Humanos , Concentração de Íons de Hidrogênio , Lacticaseibacillus rhamnosus/crescimento & desenvolvimento , Lacticaseibacillus rhamnosus/isolamento & purificação , Metilnitronitrosoguanidina/química , Metilnitronitrosoguanidina/metabolismo , Viabilidade Microbiana , Mutagênicos/química , Fenilenodiaminas/química , Fenilenodiaminas/metabolismo , Quinoxalinas/química , Quinoxalinas/metabolismoRESUMO
A simple, accurate, rapid, specific and reproducible UV spectrophotometric method was developed for estimation of content uniformity of atenolol and losartan potassium in its combined tablet dosage form. The method involves formation and solving the simultaneous equation using 226.4 and 254 nm as two wavelengths for atenolol and losartan, respectively. Developed method was employed to determine the atenolol and losartan content in ten individual tablet units of five market formulations. Methanol was used as solvent. The method was validated. From the results, it was concluded that all brands are within the content uniformity limit, 85-115%.
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BACKGROUND: Stigma and discrimination, particularly in access to healthcare, remains a major problem for people Infected with HIV in most parts of India. METHODS: We did a multicentre study (n = 10) with a cross-sectional survey design using a standardized, interviewer-administered questionnaire. RESULTS: A total of 2200 healthcare providers participated. The knowledge, attitude and practice (KAP) related to HIV service delivery were very poor with a mean overall KAP score of only 49.7% (CI: 49.1-50.3). Only 5%, 5% and 1% of the participants scored more than 75% separately for the dimensions of knowledge, attitude and practice, respectively. Only 24.4% and 36.7% of responders knew that HIV screening was not recommended prior to surgery and pre-employment check-up. Many doctors (19.4%) had refused treatment to people living with HIV/AIDS (PLHA) at least some of the time and nearly half (47.2%) identified and labelled them; 23.9% isolated them in separate care areas and 13.3% postponed or changed treatment based on the patient's HIV status. Screening for HIV prior to elective surgery was done by 67% of providers. While 64.7% of responders were aware of the existence of national guidelines on and recommendations for HIV testing, only 38.4% had read the policy document. CONCLUSION: There is a growing need to provide care, support and treatment to a large number of PLHA. The capacity of healthcare providers must be urgently built up so as to improve their knowledge of and attitude to HIV to enable them to deliver evidence-based and compassionate care to PLHA in various healthcare settings.
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Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Competência Clínica , Infecções por HIV/diagnóstico , Política de Saúde , Programas de Rastreamento/normas , Política Organizacional , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/estatística & dados numéricos , Sorodiagnóstico da AIDS , Análise por Conglomerados , Infecções por HIV/prevenção & controle , Infecções por HIV/terapia , Pesquisas sobre Atenção à Saúde , Hospitais/normas , Humanos , Índia , Programas de Rastreamento/estatística & dados numéricos , Preconceito , Atenção Primária à Saúde/normas , Setor Privado/normas , Setor Público/normas , Recusa em Tratar , Estereotipagem , Inquéritos e Questionários , Precauções UniversaisRESUMO
BACKGROUND: Inhaled endotoxin or lipopolysaccharide (LPS) is implicated in the pathogenesis of pulmonary diseases. We investigated the inhalation effects of two different doses of LPS in healthy human subjects. METHODS: Eighteen healthy non-atopic human subjects inhaled either 15 microg (n=10) or 50 microg (n=8)Escherichia coli LPS in an open study. As control, each subject had isotonic saline inhalation 1 week before (baseline) and after LPS inhalation. Data collected included those of clinical parameter, induced sputum and peripheral blood CD4+ and CD8+ T cells. RESULTS: Acute flu-like symptoms and pyrexia were significantly greater in the 50 microg than 15 microg LPS group. Similarly, the increase in sputum and blood total cell and neutrophil counts at 6h following inhaled LPS were greater in the 50 microg group. Myeloperoxidase, human neutrophil elastase and interleukin-8 in sputum sol, but not blood, showed a trend towards greater increase following 50 microg LPS. All these changes were resolved at one week. In the 50 microg dose group alone, there was a reduction in the proportion of peripheral blood interferon (IFN)-gamma-producing CD4+ and CD8+ T cells at 6h followed by an increase at 1 week after inhaled LPS. CONCLUSIONS: The airway and systemic effects of inhaled LPS are dose-related and predominantly neutrophilic. The changes in the proportions of circulating CD4+ and CD8+ T cells suggests preferential recruitment of IFN-gamma-producing T cells into tissue from inhaled 50 microg LPS, followed by reappearance of these cells in blood 1 week later.
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Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Lipopolissacarídeos/efeitos adversos , Administração por Inalação , Adulto , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Lipopolissacarídeos/administração & dosagem , Contagem de Linfócitos , Masculino , Escarro/citologiaRESUMO
White-rot fungi (WRF) are ubiquitous in nature with their natural ability to compete and survive. WRF are the only organisms known to have the ability to degrade and mineralize recalcitrant plant polymer lignin. Their potential to degrade second most abundant carbon reserve material lignin on the earth make them important link in global carbon cycle. WRF degrade lignin by its unique ligninolytic enzymatic machinery including lignin peroxidase, manganese peroxidase, laccase, cellobiose dehydrogenase, H2O2-generating enzymes, etc. The ligninolytic enzymes system is non-specific, extracellular and free radical based that allows them to degrade structurally diverse range of xenobiotic compounds. Lignin peroxidase and manganese peroxidase carry out direct and indirect oxidation as well as reduction of xenobiotic compounds. Indirect reactions involved redox mediators such as veratryl alcohol and Mn2+. Reduction reactions are carried out by carboxyl, superoxide and semiquinone radicals, etc. Methylation is used as detoxification mechanism by WRF. Highly oxidized chemicals are reduced by transmembrane redox potential. Degradation of a number of environmental pollutants by ligninolytic system of white rot fungi is described in the present review.
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Basidiomycota/enzimologia , Lignina/metabolismo , Xenobióticos/química , Basidiomycota/crescimento & desenvolvimento , Biodegradação AmbientalRESUMO
Manganese peroxidase (MnP) was produced by shallow stationary cultures of Phanerochaete chrysosporium growing on N-limited medium. Decolorization of sulfonphthalein (SP) dyes by MnP was investigated. The MnP activity profile and decolorization of SP dyes was correlated and almost all dyes were decolorized at pH 4.0. The influence of various inhibitors on Bromocresol Purple decolorization suggested an oxidative nature of the MnP-catalyzed decolorization of SP dyes.
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Corantes/metabolismo , Peroxidases/metabolismo , Phanerochaete/enzimologia , Fenolftaleínas/metabolismo , Quelantes/farmacologia , Colorimetria , Cisteína/farmacologia , Ácido Edético/farmacologia , Poluentes Ambientais/metabolismo , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Peroxidases/antagonistas & inibidores , Azida Sódica/farmacologiaRESUMO
Synaptotagmin has been proposed to function as a Ca(2+) sensor that regulates synaptic vesicle exocytosis, whereas the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex is thought to form the core of a conserved membrane fusion machine. Little is known concerning the functional relationships between synaptotagmin and SNAREs. Here we report that synaptotagmin can facilitate SNARE complex formation in vitro and that synaptotagmin mutations disrupt SNARE complex formation in vivo. Synaptotagmin oligomers efficiently bind SNARE complexes, whereas Ca(2+) acting via synaptotagmin triggers cross-linking of SNARE complexes into dimers. Mutations in Drosophila that delete the C2B domain of synaptotagmin disrupt clathrin AP-2 binding and endocytosis. In contrast, a mutation that blocks Ca(2+)-triggered conformational changes in C2B and diminishes Ca(2+)-triggered synaptotagmin oligomerization results in a postdocking defect in neurotransmitter release and a decrease in SNARE assembly in vivo. These data suggest that Ca(2+)-driven oligomerization via the C2B domain of synaptotagmin may trigger synaptic vesicle fusion via the assembly and clustering of SNARE complexes.
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Proteínas de Ligação ao Cálcio , Cálcio/metabolismo , Fusão de Membrana/fisiologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Vesículas Sinápticas/metabolismo , Proteínas de Transporte Vesicular , Subunidades alfa do Complexo de Proteínas Adaptadoras , Proteínas Adaptadoras de Transporte Vesicular , Animais , Biopolímeros/biossíntese , Biopolímeros/química , Cálcio/farmacologia , Dimerização , Drosophila , Endocitose/fisiologia , Exocitose/fisiologia , Substâncias Macromoleculares , Fusão de Membrana/efeitos dos fármacos , Glicoproteínas de Membrana/química , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Mutação , Proteínas do Tecido Nervoso/química , Testes de Precipitina , Conformação Proteica , Estrutura Terciária de Proteína/genética , Ratos , Proteínas SNARE , Relação Estrutura-Atividade , SinaptotagminasRESUMO
The synaptic vesicle protein synaptotagmin I has been proposed to serve as a Ca(2+) sensor for rapid exocytosis. Synaptotagmin spans the vesicle membrane once and possesses a large cytoplasmic domain that contains two C2 domains, C2A and C2B. Multiple Ca(2+) ions bind to the membrane proximal C2A domain. However, it is not known whether the C2B domain also functions as a Ca(2+)-sensing module. Here, we report that Ca(2+) drives conformational changes in the C2B domain of synaptotagmin and triggers the homo- and hetero-oligomerization of multiple isoforms of the protein. These effects of Ca(2)+ are mediated by a set of conserved acidic Ca(2)+ ligands within C2B; neutralization of these residues results in constitutive clustering activity. We addressed the function of oligomerization using a dominant negative approach. Two distinct reagents that block synaptotagmin clustering potently inhibited secretion from semi-intact PC12 cells. Together, these data indicate that the Ca(2)+-driven clustering of the C2B domain of synaptotagmin is an essential step in excitation-secretion coupling. We propose that clustering may regulate the opening or dilation of the exocytotic fusion pore.
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Sinalização do Cálcio/fisiologia , Cálcio/fisiologia , Exocitose/fisiologia , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/fisiologia , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/fisiologia , Sequência de Aminoácidos , Animais , Sítios de Ligação , Proteínas de Ligação ao Cálcio/química , Proteínas de Ligação ao Cálcio/fisiologia , Grânulos Citoplasmáticos/fisiologia , Endocitose , Membranas Intracelulares/fisiologia , Substâncias Macromoleculares , Fusão de Membrana , Dados de Sequência Molecular , Células PC12 , Isoformas de Proteínas/química , Isoformas de Proteínas/fisiologia , Ratos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Sinaptotagmina I , SinaptotagminasRESUMO
Development of naive T cells into type 1 (Th1, Tc1) or type 2 (Th2, Tc2) effector cells is thought to be under the control of cytokines. In this study, we show that when both IL-12 and IL-4 are present, murine and human T cell differentiation is regulated by the balance of protein kinase C (PKC) and calcium signaling within T cells. Although both biochemical signals were required for T cell activation via the TCR, altering the balance between them redirected type 1 cells to type 2 and vice versa. Stimulation of calcium signaling or inhibition of PKC favored type 1 differentiation, whereas stimulation of PKC or inhibition of calcineurin resulted in type 2 effectors. Altered peptide ligands induced distinct balances of PKC/calcium signaling and altered Tc1/Tc2 development in TCR-transgenic CD8 T cells. The data suggest novel strategies for manipulation of the immune response in vivo.
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Sinalização do Cálcio/imunologia , Proteína Quinase C/fisiologia , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/enzimologia , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/enzimologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/enzimologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Calcineurina/fisiologia , Sinalização do Cálcio/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Células Clonais , Humanos , Ionomicina/farmacologia , Ligantes , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/enzimologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Células Th2/efeitos dos fármacos , Células Th2/enzimologia , Células Th2/imunologia , Células Th2/metabolismoRESUMO
It has recently become clear that distinct subsets of CD8 T cells, analogous to their CD4 counterparts, exist in rodents and humans. To examine functional differences between human CD8 T-cell subsets, we generated Tc1, Tc2, and Tc0 T-cell clones from the peripheral blood of healthy individuals. The majority of CD8 T-cell clones generated displayed a classic Tc1 phenotype, but 10% to 20% secreted interleukin (IL)-4 in addition to interferon-gamma (Tc0 phenotype). Generation of Tc2 clones was dependent on the use of anti-CD3 and anti-CD28 as the primary stimulus. The cytokine profiles of established clones remained susceptible to modification by the addition of IL-12 and IL-4. In addition, IL-12 enhanced and IL-4 inhibited the growth of Tc1 but not Tc2/0 CD8 T-cell clones. Significant functional differences were observed between the subsets. Tc2/0 clones expressed CD30 and CD40 ligand at a much higher level than Tc1 clones. Both Tc1 and Tc2/0 clones showed comparable cytotoxicity and produced similar levels of perforin and Fas L. However, Tc2 clones were much more resistant to activation-induced cell death and less susceptible to apoptosis by direct Fas ligation. Moreover, Tc1 and Tc2 clones had opposing effects on the development of CD4 effectors, promoting type 1 and type 2 responses, respectively. These data provide evidence for profound differences between human CD8 T-cell subsets that may be important in their functions as cytotoxic or immunoregulatory cells. (Blood. 2000;95:231-240)