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1.
Curr Microbiol ; 80(1): 41, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36534266

RESUMO

Streptococcus pneumoniae (SP) infections cause morbidity and mortality among children worldwide. Hence India introduced 13-valent pneumococcal conjugate vaccine (PCV-13) in 2017 in a phased manner. The primary objective of this study was to assess the proportion of healthy children having nasopharyngeal colonization (NP) with SP. Secondary objective was to determine prevalent serotype of SP among the PCV13 vaccinated and non-vaccinated children. This cross-sectional study was conducted in 4 hospitals of Lucknow District, Northern India. Three hundred healthy children (2-59 months) were recruited between July and August 2019 from vaccination-clinics of hospitals. NP specimen was cultured using 5% sheep blood agar plate containing gentamicin. Pneumococcal isolates were identified by optochin sensitivity and bile-solubility tests. Serotyping was done using Quellung Method. Of the 300 healthy children, 56.7% (170/300) were males and 59.3% (181/300) had received at least one dose of PCV13 vaccine. The NP carriage rate of SP among healthy children was 37.7% (113/300). Vaccine serotypes were found in 33.3% (22/66) in PCV vaccinated children and 48.9% (23/47) in non-vaccinated children (p 0.09). Common vaccine serotypes that isolated were: 18C, 19A, 19F, 23F, 3, 4, 6A, 6B, 9 V. Thus more than one-third of healthy children had NP colonization with SP. Adjusting for age, there was a trend for significant reduction in vaccine serotypes in the NP with one doses versus two or more doses (ptrend = 0.04).


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Masculino , Animais , Ovinos , Feminino , Sorogrupo , Estudos Transversais , Portador Sadio , Infecções Pneumocócicas/prevenção & controle , Índia
2.
Langmuir ; 38(5): 1738-1747, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35084868

RESUMO

Non-equilibrium molecular dynamics simulations are used to probe the driving forces behind the formation of highly ordered, epitaxially connected superlattices of polyhedral-shaped nanoparticles (NPs) at fluid-fluid interfaces. By explicitly modeling coarse-grained ligands that cap the NP surface, it is shown that differences in NP shapes and time-dependent facet-specific ligand densities give rise to drastically different transformation mechanisms. Our results indicate that the extent of screening of the inter-particle interactions by the surrounding solvation environment has a significant impact on reversibility and ultimately the coherence of the final two-dimensional superlattice obtained. For the particle shapes examined, a hexagonal pre-assembly and a square superlattice final assembly (upon preferential ligand desorption from {100} facets) were prevalent; however, cuboctahedral NPs formed intermediate epitaxially bonded branched clusters, which eventually grew and rearranged into a square lattice; in contrast, truncated octahedral NPs exhibited an abrupt rhombic-to-square transition driven by the clustering of their numerous {111}-ligands that favored the stacking of linear NP rods. To track the incipient order in the system, we also outline a set of novel order parameters that measure the local orientation alignment between nearest-neighbor pairs. The simulation protocols advanced in this work could pave the way forward for exploration of the vast phase space associated with the interfacial self-assembly of NPs.

3.
J Chem Theory Comput ; 16(9): 5866-5875, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32786915

RESUMO

This study outlines the development of an implicit-solvent model that reproduces the behavior of colloidal nanoparticles at a fluid-fluid interface. The center point of this formulation is the generalized quaternion-based orientational constraint (QOCO) method. The model captures three major energetic characteristics that define the nanoparticle configuration-position (orthogonal to the interfacial plane), orientation, and inter-nanoparticle interaction. The framework encodes physically relevant parameters that provide an intuitive means to simulate a broad spectrum of interfacial conditions. Results show that for a wide range of shapes, our model is able to replicate the behavior of an isolated nanoparticle at an explicit fluid-fluid interface, both qualitatively and often nearly quantitatively. Furthermore, the family of truncated cubes is used as a test bed to analyze the effect of changes in the degree of truncation on the potential-of-mean-force landscape. Finally, our results for the self-assembly of an array of cuboctahedra provide corroboration to the experimentally observed honeycomb and square lattices.

4.
Clin Microbiol Infect ; 24(12): 1305-1310, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29496597

RESUMO

OBJECTIVES: Antimicrobial resistance (AMR) is a priority for surveillance in bacterial infections. For leprosy, AMR has not been assessed because Mycobacterium leprae does not grow in vitro. We aim to obtain AMR data using molecular detection of resistance genes and to conduct a prospective open survey of resistance to antileprosy drugs in countries where leprosy is endemic through a WHO surveillance network. METHODS: From 2009 to 2015, multi-bacillary leprosy cases at sentinel sites of 19 countries were studied for resistance to rifampicin, dapsone and ofloxacin by PCR sequencing of the drug-resistance-determining regions of the genes rpoB, folP1 and gyrA. RESULTS: Among 1932 (1143 relapse and 789 new) cases studied, 154 (8.0%) M. leprae strains were found with mutations conferring resistance showing 182 resistance traits (74 for rifampicin, 87 for dapsone and 21 for ofloxacin). Twenty cases showed rifampicin and dapsone resistance, four showed ofloxacin and dapsone resistance, but no cases were resistant to rifampicin and ofloxacin. Rifampicin resistance was observed among relapse (58/1143, 5.1%) and new (16/789, 2.0%) cases in 12 countries. India, Brazil and Colombia reported more than five rifampicin-resistant cases. CONCLUSIONS: This is the first study reporting global data on AMR in leprosy. Rifampicin resistance emerged, stressing the need for expansion of surveillance. This is also a call for vigilance on the global use of antimicrobial agents, because ofloxacin resistance probably developed in relation to the general intake of antibiotics for other infections as it is not part of the multidrug combination used to treat leprosy.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana/genética , Hanseníase/epidemiologia , Mycobacterium leprae/efeitos dos fármacos , Mycobacterium leprae/genética , Antibacterianos/efeitos adversos , Proteínas de Bactérias/genética , Biópsia por Agulha , Brasil/epidemiologia , Colômbia/epidemiologia , DNA Girase/genética , Dapsona/uso terapêutico , Doenças Endêmicas/estatística & dados numéricos , Monitoramento Epidemiológico , Saúde Global , Humanos , Índia/epidemiologia , Hanseníase/diagnóstico , Hanseníase/tratamento farmacológico , Hanseníase/microbiologia , Testes de Sensibilidade Microbiana , Mutação , Ofloxacino/uso terapêutico , Reação em Cadeia da Polimerase , Estudos Prospectivos , Recidiva , Rifampina/uso terapêutico , Vigilância de Evento Sentinela , Pele/microbiologia , Pele/patologia , Inquéritos e Questionários , Organização Mundial da Saúde
5.
Indian J Tuberc ; 65(2): 152-158, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29579430

RESUMO

Mycobacterium indicus pranii (MIP) already established as an immune-modulator in mycobacterial infections generates immune response by acting on CXC chemokines. In the present study, the immunomodulatory effect of MIP in conjunction with chemotherapy against M.tb infection was evaluated by colony forming units (CFUs) following aerosol infection to guinea pig and by measuring CXCL12 chemokine expression using q-PCR and in situ RT-PCR. Different experimental groups included, infection (Rv), immunoprophylaxis (RvMw), chemotherapy (RvCh) and combination of immunoprophylaxis+chemotherapy (RvChMw) group and normal healthy (NH) group. In the combination of immunoprophylaxis+chemotherapy (RvChMw) group, the CFU counts reduced significantly (p<0.001) at 4th week of infection as compared to other treated groups (RvMw and RvCh group). The expression of CXCL12 was recorded in all the treated groups of animals. The study demonstrated suppressed expression of CXCL 12 in both immunoprophylaxis as well as chemotherapy groups (6th and 8th week) that become elevated in immunoprophylaxis plus chemotherapy group (10th week), at which time point no CFUs were detected in RvCh and RvChMw group. The findings indicate that the expression of CXCL12 is associated with good response to anti - tubercular treatment. Thus, prior immunization with MIP appears to show good immunomodulatory effect to release CXCL12 chemokine during infection and also correlates with enhanced effect to chemotherapy.


Assuntos
Antituberculosos/uso terapêutico , Quimiocina CXCL12/sangue , Pulmão/imunologia , Mycobacterium tuberculosis/imunologia , Micobactérias não Tuberculosas/imunologia , Tuberculose Pulmonar/tratamento farmacológico , Animais , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Quimioterapia Combinada , Cobaias , Imunoterapia , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/imunologia
6.
Waste Manag ; 74: 110-122, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29331488

RESUMO

End-of-life (EOL) tyres and their decomposition present severe environmental concern due to their resistance to moisture, oxygen, natural degradation, etc. Pyrolysis is considered to be the most effective and sustainable process for recycling, due to its eco-friendly process. The current work studied the effect of recycled carbon black (rCB), obtained from the pyrolysis of EOL tyres, on the properties of ethylene propylene diene rubber (EPDM). The rCB was characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and chemical methods. rCB was incorporated solely, into a conventional EPDM formulation and also in combination with N550 carbon black. The physico-mechanical properties of the EPDM vulcanizates, before and after aging, were succinctly studied by SEM, TGA, Differential Scanning Calorimetry (DSC), tensile tests and cross-link density. The average particle size of rCB was observed to be 8 µm and the ash content was observed to be higher when compared to the conventional N550 carbon black, which was evident, by the TGA and SEM-EDX analyses. The reinforcing effect and the cross-link density of the rCB-filled vulcanizates were found to be marginally inferior in comparison to the conventional carbon black (N550). The morphology of the tensile- and tear-fractured surfaces were studied by SEM and it was observed that the breaking mechanism follows the rubber chain detachment from the surface mode.


Assuntos
Reciclagem , Borracha , Fuligem , Humanos , Microscopia Eletrônica de Varredura , Eliminação de Resíduos
8.
ACS Appl Mater Interfaces ; 9(12): 10664-10672, 2017 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-28267317

RESUMO

Generation of hydrogen by photochemical, electrochemical, and other means is a vital area of research today, and a variety of materials have been explored as catalysts for this purpose. C3N4, MoS2, and nitrogenated RGO (NRGO) are some of the important catalytic materials investigated for the hydrogen evolution reaction (HER) reaction, but the observed catalytic activities are somewhat marginal. Prompted by preliminary reports that covalent cross-linking of 2D materials to generate heteroassemblies or nanocomposites may have beneficial effect on the catalytic activity, we have synthesized nanocomposites wherein C3N4 is covalently bonded to MoS2 or NRGO nanosheets. The photochemical HER activity of the C3N4-MoS2 nanocomposite is found to be remarkable with an activity of 12778 µmol h-1 g-1 and a turnover frequency of 2.35 h-1. The physical mixture of C3N4 and MoS2, on the other hand, does not exhibit notable catalytic activity. Encouraged by this result, we have studied electrochemical HER activity of these composites as well. C3N4-MoS2 shows superior activity relative to a physical mixture of MoS2 and C3N4. Density functional theory calculations have been carried out to understand the HER activity of the nanocomposites. Charge-transfer between the components and greater planarity of cross-linked layers are important causes of the superior catalytic activity of the nanocomposites. Covalent linking of such 2D materials appears to be a worthwhile strategy for catalysis and other applications.

9.
Recent Pat Biotechnol ; 11(2): 120-140, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28215141

RESUMO

BACKGROUND: Endophytic fungi are taxonomically and ecologically heterogeneous group of organisms, mainly belonging to the Ascomycotina and Deuteromycotina. Endophytes usually produce the enzymes necessary for the colonization of plant tissues. Endophytes are able to utilize components of plant cells without disturbing host metabolism, which is confirmed by isozyme analysis and studies on substrate utilization. The patents related to enzymes and metabolites produced by endophytic fungi are associated with their ecological significance. Application of metabolites and growth promoting factors produced from endophytic fungi, in the pharmaceutical and agricultural industries, is now well established. The patents on secretion of extracellular enzymes in vitro by endophytic fungi needed for cell wall degradation, support the hypothesis that fungal endophytes represent a group of organisms specialized to live within plant tissue. OBJECTIVE: This review presents the patents granted on different aspects of endophytic fungi for the last 11 years. This expresses the scenario and impact of these patents regarding significance in human society. CONCLUSION: In the last few years, research and inventions regarding the different aspects of endophytic fungi beneficial for host plant as well as for human beings have been carried out, which is supported by the increasing number of patents granted on endophytic fungi.


Assuntos
Ascomicetos , Produção Agrícola/legislação & jurisprudência , Indústria Farmacêutica/legislação & jurisprudência , Endófitos , Fungos Mitospóricos , Produção Agrícola/métodos , Indústria Farmacêutica/métodos , Humanos , Patentes como Assunto
10.
Pestic Biochem Physiol ; 127: 28-37, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26821655

RESUMO

The present paper reports the effects of Metarhizium anisopliae, Isaria fumosoroseus and Hirsutella thompsonaii on Periplaneta americana. I. fumosoroseus and H. thompsonaii were cultured at 28±1°C on potato carrot agar and M. anisopliae was cultured at 28±1°C on potato dextrose agar for 14days. Conidial suspensions of fungi were given to cockroaches through different routes. M. anisopliae shows high virulence against adult cockroaches and mortality ranges from 38.65% to 78.36% after 48h. I. fumosoroseus and H. thompsonii show less virulence compared to M. anisopliae. We also investigated the effect of these three fungi on the activity of lactate dehydrogenase, lipid peroxidation and catalase in different tissues of the insect to gain an understanding of the different target site. The result suggested that the activity of lactate dehydrogenase, catalase and level of malondialdehyde varies in different organs and through different routes of exposure. Based on mortality percentages, all tested fungi had high potentials for biocontrol agents against P. americana. Our study reveals for the first time that I. fumosoroseus and H. thompsonaii fungal infections initiate oxidative stress in the midgut, fat body, whole body and hemolymph of cockroach thereby suggesting them to be the target organs for oxidative damage.


Assuntos
Fungos/patogenicidade , Estresse Oxidativo , Periplaneta/metabolismo , Animais , Periplaneta/microbiologia , Controle Biológico de Vetores , Virulência
11.
Kathmandu Univ Med J (KUMJ) ; 14(56): 376-379, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29336430

RESUMO

Pregnancy over the cesarean scar is the rarest cause of ectopic pregnancy and development of persistent trophoblastic disease at the scar site is extremely rare. A high index of suspicion is needed for early diagnosis and management of cesarean scar molar pregnancy. This condition is difficult to diagnose and must be considered in the patient with a history of cesarean section who has persistent vaginal bleeding or symptoms of pregnancy after suction evacuation. Diagnosis can be confirmedby measuring ß Human Chorionic Gonadotropin levels, transvaginal ultrasound with doppler flow evaluation. As this is an uncommon condition, this case report with conservative non surgical approach will add up to its clinical spectrum.


Assuntos
Cesárea/efeitos adversos , Cicatriz/patologia , Gravidez Ectópica/diagnóstico , Gravidez Ectópica/patologia , Trofoblastos/patologia , Adulto , Feminino , Humanos , Gravidez , Ultrassonografia , Hemorragia Uterina/etiologia
12.
Indian J Med Res ; 142(3): 323-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26458349

RESUMO

BACKGROUND & OBJECTIVES: Studies have shown the bactericidal potential of econazole and clotrimazole against Mycobacterium tuberculosis under in vitro and ex vivo conditions along with their synergism with conventional antituberculosis drugs. These molecules were also found to be effective against different multidrug resistant (MDR) M. tuberculosis isolates in vitro. Hence the present study was designed to evaluate the in vivo antimycobacterial potential of moxifloxacin and econazole alone and in combination against multidrug resistant tuberculosis (MDR-TB) in a mice model. METHODS: Mice were infected with 2.5×10 [7] bacilli of MDR strain of M. tuberculosis by aerosol route of infection. After four weeks of infection, chemotherapy was started orally by moxifloxacin 8.0 mg/kg body wt and econazole 3.3 mg/kg alone and in combination, as well as with four first line anti-tuberculosis drugs as a positive control. The animals were sacrificed and the lungs and spleen were excised under aspetic conditions. The tissues were homogenized with sterile normal saline, an aliquot of the homogenate was plated on Middlebrook 7H11 agar supplemented with oleate albumin dextrose catalase (OADC) and incubated at 37°C for four weeks. The number of visible and individual colonies were counted. RESULTS: The first line anti-tuberculosis drugs (RIF+INH+EMB+PZA) after eight weeks of therapy had no impact as the bacillary load in lungs and spleens remained unchanged. However, econazole, moxifloxacin alone as well as in combination significantly reduced the bacillary load in lungs as well as in spleens of MDR-TB bacilli infected mice. INTERPRETATION & CONCLUSIONS: Co-administration of the two drugs (econazole and moxifloxacin) to MDR-TB strain JAL-7782 infected mice exhibited additive effect, the efficacy of the drugs in combination being higher as compared with ECZ or MOX alone. These results were substantiated by histopathological studies. This study suggests the utility of econazole for the treatment of MDR tuberculosis and warrants further work in this direction.


Assuntos
Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Animais , Modelos Animais de Doenças , Econazol/administração & dosagem , Fluoroquinolonas/administração & dosagem , Humanos , Camundongos , Moxifloxacina , Mycobacterium tuberculosis/patogenicidade , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/patologia
13.
Microbes Infect ; 17(4): 247-57, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25576930

RESUMO

Autoantibodies against various components of host are known to occur in leprosy. Nerve damage is the primary cause of disability associated with leprosy. The aim of this study was to detect the level of autoantibodies and lympho-proliferative response against myelin basic protein (MBP) in leprosy patients (LPs) and their correlation with clinical phenotypes of LPs. Further, probable role of molecular mimicry in nerve damage of LPs was investigated. We observed significantly high level of anti-MBP antibodies in LPs across the spectrum and a positive significant correlation between the level of anti-MBP antibodies and the number of nerves involved in LPs. We report here that 4 B cell epitopes of myelin A1 and Mycobacterium leprae proteins, 50S ribosomal L2 and lysyl tRNA synthetase are cross-reactive. Further, M. leprae sonicated antigen hyperimmunization was responsible for induction of autoantibody response in mice which could be adoptively transferred to naive mice. For the first time our findings suggest the role of molecular mimicry in nerve damage in leprosy.


Assuntos
Doenças Desmielinizantes/microbiologia , Hanseníase/microbiologia , Lisina-tRNA Ligase/fisiologia , Mimetismo Molecular/fisiologia , Mycobacterium leprae/patogenicidade , Proteína Básica da Mielina/fisiologia , Proteínas Ribossômicas/fisiologia , Animais , Doenças Desmielinizantes/complicações , Doenças Desmielinizantes/etiologia , Humanos , Hanseníase/complicações , Hanseníase/etiologia , Camundongos , Camundongos Endogâmicos BALB C/sangue , Coelhos
14.
J Pediatr Urol ; 10(6): 1001-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25486943

RESUMO

OBJECTIVE: To find out the relative prevalence of renal anomalies detected in the antenatal period, and to look at factors that predict the postnatal outcome. METHODS: In this prospective study, all antenatal-detected renal anomalies booked at the tertiary health centre were evaluated and counselled. Aspects such as type of renal anomaly, oligohydramnios and presence of additional anomalies were noted. Stillborn babies underwent autopsy; all live born babies were followed for one year. Appropriate statistical analyses were performed to compare the antenatal factors with outcomes. RESULTS: Renal anomalies were detected in 136 out of 587 cases with major fetal anomalies. Most of the women were primiparous (65.4%). The mean gestation at presentation was 30 weeks; in 12 cases, diagnosis was possible before 20 weeks (8.8%). Antenatal hydronephrosis was the most commonly seen anomaly, with 61 cases; this was followed by bilateral cystic kidney in 50 cases. Out of the 136 cases, 12 (8.8%) underwent termination of pregnancy and 60 (44.1%) babies were stillborn. Autopsy was performed in 58 out of 72 (80.6%) cases after consent. Karyotyping was performed in 49 cases and abnormalities were detected in two (4.1%) of them. A total of 64 (47.1%) babies were live born; after one year, 49 (36.0%) of them were alive. Postnatal survival was highest in unilateral disease (85.7%). In cases with oligohydramnios, there was only 3.4% survival after one year; none of the cases with cystic kidney and oligohydramnios survived. The period of gestation at presentation of non-survivors was 25.9 weeks compared to 32.5 weeks with survivors. Among the cases with extra renal anomaly, 7.0% survived; none of the cases with associated cranio-vertebral defect or polydactyly survived after a year. CONCLUSION: Out of the different renal pathologies that were diagnosed, survival was highest in the unilateral group. The factors associated with poor prognosis included bilateral disease, absence of amniotic fluid and presence of associated malformation.


Assuntos
Nefropatias/congênito , Rim/anormalidades , Adolescente , Adulto , Feminino , Idade Gestacional , Humanos , Índia/epidemiologia , Lactente , Mortalidade Infantil/tendências , Recém-Nascido , Rim/diagnóstico por imagem , Rim/embriologia , Nefropatias/embriologia , Nefropatias/mortalidade , Masculino , Gravidez , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida/tendências , Ultrassonografia Pré-Natal , Adulto Jovem
15.
Tissue Antigens ; 84(5): 492-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25273327

RESUMO

This study was aimed to assess the association of Protein tyrosine phosphatase non-receptor22 (PTPN22) gene single nucleotide polymorphisms (SNPs) with rheumatic heart disease (RHD) susceptibility in 400 RHD patients and 300 controls. The PTPN22 polymorphisms (rs2476601, rs1217406 and rs3789609) were genotyped using Taqman probes (Applied Biosystems, Foster City, CA). Statistical analysis was performed by spss and haplotype analysis by snpstat. The frequencies of variant alleles were not different between controls and cases (rs2476601: 2.00% & 1.05%; rs1217406: 36.33% & 34.75%; and rs3789609: 38.17% & 40.00%, respectively]. However, G rs2476601 A rs1217406 T rs3789609 haplotype turned out to be a low risk factor for RHD (P = 0.0042) predisposition in females and adult patients. This study suggests PTPN22 haplotype may modulate the risk to RHD in North Indians.


Assuntos
Alelos , Frequência do Gene , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Cardiopatia Reumática/genética , Adolescente , Criança , Feminino , Humanos , Índia/etnologia , Masculino , Pessoa de Meia-Idade , Cardiopatia Reumática/etnologia
16.
Mol Biol Rep ; 41(1): 285-96, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24234750

RESUMO

The Rv3203 (LipV) of Mycobacterium tuberculosis (Mtb) H37Rv, is annotated as a member of Lip family based on the presence of characteristic consensus esterase motif 'GXSXG'. In vitro culture studies of Mtb H37Ra indicated that expression of Rv3203 gene was up-regulated during acidic stress as compared to normal whereas no expression was observed under nutrient and oxidative stress conditions. Therefore, detailed characterization of Rv3203 was done by gene cloning and its further expression and purification as his-tagged protein in microbial expression system. The enzyme was purified to homogeneity by affinity chromatography. It demonstrated broad substrate specificity and preferentially hydrolyzed p-nitrophenyl myristate. The purified enzyme demonstrated an optimum activity at pH 8.0 and temperature 50 °C. The specific activity, K m and V max of enzyme was determined to be 21.29 U mg(-1) protein, 714.28 µM and 62.5 µmol ml(-1) min(-1), respectively. The pH stability assay and circular dichroism spectroscopic analysis revealed that Rv3203 protein is more stable in acidic condition. Tetrahydrolipstatin, a specific lipase inhibitor and RHC80267, a diacylglycerol lipase inhibitor abolished the activity of this enzyme. The catalytic triad residues were determined to be Ser50, Asp180 and His203 residues by site-directed mutagenesis.


Assuntos
Proteínas de Bactérias/genética , Lipase/genética , Mycobacterium tuberculosis/enzimologia , Sequência de Aminoácidos , Substituição de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Domínio Catalítico , Cromatografia de Afinidade , Dicroísmo Circular , Sequência Conservada , Indução Enzimática , Estabilidade Enzimática , Regulação Bacteriana da Expressão Gênica , Concentração de Íons de Hidrogênio , Cinética , Lipase/química , Lipase/isolamento & purificação , Lipase/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Estrutura Secundária de Proteína , Estresse Fisiológico , Especificidade por Substrato
17.
Pediatr Cardiol ; 35(1): 180-2, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24030589
18.
Indian J Chest Dis Allied Sci ; 56(4): 221-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25962195

RESUMO

BACKGROUND: Most of the Indian studies on prediction equations for spirometry in adults are several decades old and may have lost their utility as these were carried out with equipment and standardisation protocols that have since changed. Their validity is further questionable as the lung health of the population is likely to have changed over time. OBJECTIVE: To develop prediction equations for spirometry in adults of north Indian origin using the 2005 American Thoracic Society/European Respiratory Society (ATS/ERS) recommendations on standardisation. METHODS: Normal healthy non-smoker subjects, both males and females, aged 18 years and above underwent spirometry using a non-heated Fleisch Pneumotach spirometer calibrated daily. The dataset was randomly divided into training (70%) and test (30%) sets and the former was used to develop the equations. These were validated on the test data set. Prediction equations were developed separately for males and females for forced vital capacity (FVC), forced expiratory volume in first second (FEV1), FEV1/FVC ratio, and instantaneous expiratory flow rates using multiple linear regression procedure with different transformations of dependent and/or independent variables to achieve the best-fitting models for the data. The equations were compared with the previous ones developed in the same population in the 1960s. RESULTS: In all, 685 (489 males, 196 females) subjects performed spirometry that was technically acceptable and repeatable. All the spirometry parameters were significantly higher among males except the FEV1/FVC ratio that was significantly higher in females. Overall, age had a negative relationship with the spirometry parameters while height was positively correlated with each, except for the FEV1/FVC ratio that was related only to age. Weight was included in the models for FVC, forced expiratory flow (FEF75) and FEV1/FVC ratio in males, but its contribution was very small. Standard errors of estimate were provided to enable calculation of the lower limits of normal and standardised residuals for these parameters. The equations were found to be valid on the test dataset, and therefore, may be extended to general population. Comparison with the 1960s equations revealed lack of good agreement, and substantially higher predicted FVC with the current equations, especially in the forty-years-plus age group, in both males and females. Even in the age group upto 40 years, the level of agreement was clinically not acceptable. CONCLUSIONS: Validated prediction equations have been developed for spirometry variables in adults of north Indian origin using the current ATS/ERS spirometry standardisation recommendations. The equations suggest an improvement in the lung health of the population over time in the middle-aged and the elderly. These equations should address a long-felt unmet need and enable a more appropriate evaluation of spirometry data in different chest diseases in Indian subjects.


Assuntos
Fenômenos Fisiológicos Respiratórios , Espirometria , Adulto , Fatores Etários , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Fatores Sexuais , Espirometria/métodos , Espirometria/normas
19.
Infect Genet Evol ; 13: 11-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23107775

RESUMO

Mycobacterium indicus pranii (earlier known as Mycobacterium w) has been used as an immunmodulatory agent in leprosy and tuberculosis by mediating the release of various cytokines and chemokines. CXCL10 (IP-10) and CXCL11 (I-TAC) chemokines are involved in T-cell migration and stimulation of natural killer cells in Mycobacterium tuberculosis infection. In this study, the effect of heat killed M. indicus pranii (alone and in conjunction with chemotherapy) on disease progression was determined by colony forming units (CFUs) in guinea pig lung following their aerosol infection and the expression levels of CXCL10 and CXCL11 were studied by quantitative Reverse Transcriptase Polymerase Chain Reaction (qRT-PCR) and in situ RT-PCR. Four groups of animals included; infection only (Rv), immunoprophylaxis (RvMw), chemotherapy (RvCh) and combination of immunoprophylaxis with chemotherapy (RvChMw). In the group where immunoprophylaxis was given in combination with chemotherapy, the CFU counts reduced significantly at 4th week post-infection as compared to animals that received immunoprophylaxis or chemotherapy alone. At the same time, all groups of animals had elevated expression of CXCL 10 which was significantly high only in animals that received Mw with or without chemotherapy. Unlike to CXCL 10, study demonstrated suppressed expression CXCL 11 in both immunoprophylaxis as well as chemotherapy groups that became up-regulated in synergistic response of immunoprophylaxis and chemotherapy. Taken together, data indicates that the expression of CXCL10 and CXCL11 positively correlates with anti-tubercular treatment (at least with combination of immunoprophylaxis and chemotherapy). Therefore, prior immunization with Mw appears to be a good immunomodulator for release of chemokines and augments the effect of chemotherapy.


Assuntos
Quimiocina CXCL10/genética , Quimiocina CXCL11/genética , Mycobacterium tuberculosis/imunologia , Tuberculose/genética , Tuberculose/microbiologia , Animais , Carga Bacteriana , Expressão Gênica , Cobaias , Pulmão/metabolismo , Pulmão/microbiologia , Pulmão/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Tempo , Tuberculose/prevenção & controle
20.
Cell Immunol ; 278(1-2): 63-75, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23121977

RESUMO

Mycobacteria are known to induce autoimmune response in the host. Anti-host keratrin antibodies (AkAbs) might be responsible for the autoimmune phenomena in leprosy patients as majority of leprosy lesions are manifested in the skin and occurrence of keratosis is not an uncommon feature. The aim of this study was to find out the level of AkAbs in leprosy patients across the spectrum and to explore its correlation with the clinical manifestation of the disease. Further, mimicking epitopes of keratin and Mycobacterium leprae components were characterized. We screened 140 leprosy patients (27 BT, 28 BL, 41 LL, 25 T1R, 19 ENL), 74 healthy controls (HC) and 3 psoriasis patients as positive control. Highest AkAbs level was observed in the psoriasis patients followed by T1R, LL, BL, ENL, TT/BT. AkAbs level was significantly (p<0.05) higher in all the groups of leprosy patients except TT/BT in comparison to HC. Significant positive correlation was found between number of lesions and level of AkAbs in leprosy patients. Highest lympho-proliferation for keratin protein was observed in T1R, followed by BL/LL, TT/BT, ENL. Lympho-proliferation was significantly (p<0.05) higher in all groups of leprosy patients except ENL in comparison to HC. Interestingly, it was noted that hyperimmunization of inbred strains of female BALB/c mice and rabbit with M. leprae soluble antigen (MLSA) induce higher level of AkAbs. The percentage of FoxP3(+) expressing Treg cells (total CD4(+)CD25(+)FoxP3(+) andCD4(+)CD25(+hi)FoxP3(+)) in splenocytes and lymph nodes of hyperimmunized mice were declined in comparison to control mice. Further, it was found that this autoimmune response can be adoptively transferred in naïve mice by splenocytes and lymph node cells as well as T cells. Comparative molecular characterization between keratin and MLSA noted a cross-reactivity/similarity between these two antigens. The cross-reactive protein of keratin was found to be in molecular weight range ≈74-51kDa and at pI 4.5 while the cross-reactive protein of MLSA was found to be in molecular weight ≈65kDa and at pI 4-4.5. Cross-reactive protein of keratin and MLSA was identified and characterized by MALDI-TOF/TOF analysis and Mascot software. It was found that the keratin (host protein) which reacted with anti-M. leprae sera is cytokeratin-10 and MLSA which reacted with anti-keratin sera is heat shock protein 65 (HSP 65). Seven B-cell epitopes of cytokeratin-10 and HSP 65 was found to be similar by multiple sequence alignment using ClustalW server and out of which 6 B-cell epitopes were found to be on the surface of HSP 65. In conclusion, our study provides evidence for the existence of molecular mimicry between cytokeratin-10 of keratin (host protein) and 65kDa HSP (groEL2) of M. leprae. Presence of heightened CMI response of leprosy patients to keratin and positive correlation of AkAbs level with number of lesions of leprosy patients showed the clinical evidence for its role in the pathogenesis in leprosy.


Assuntos
Proteínas de Bactérias/química , Chaperonina 60/química , Queratina-10/química , Hanseníase/imunologia , Hanseníase/prevenção & controle , Mycobacterium leprae/imunologia , Transferência Adotiva , Animais , Antígenos de Bactérias/administração & dosagem , Antígenos de Bactérias/imunologia , Autoanticorpos/biossíntese , Autoanticorpos/imunologia , Proteínas de Bactérias/imunologia , Estudos de Casos e Controles , Chaperonina 60/imunologia , Reações Cruzadas , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Expressão Gênica , Humanos , Imunização , Queratina-10/imunologia , Hanseníase/microbiologia , Linfonodos/citologia , Linfonodos/imunologia , Camundongos , Mimetismo Molecular , Coelhos , Índice de Gravidade de Doença , Pele/imunologia , Pele/microbiologia , Baço/citologia , Baço/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/microbiologia
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