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1.
J Synchrotron Radiat ; 25(Pt 5): 1541-1547, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30179195

RESUMEN

The Hard X-ray Photo-Electron Spectroscopy (HAXPES) beamline (PES-BL14), installed at the 1.5 T bending-magnet port at the Indian synchrotron (Indus-2), is now available to users. The beamline can be used for X-ray photo-emission electron spectroscopy measurements on solid samples. The PES beamline has an excitation energy range from 3 keV to 15 keV for increased bulk sensitivity. An in-house-developed double-crystal monochromator [Si (111)] and a platinum-coated X-ray mirror are used for the beam monochromatization and manipulation, respectively. This beamline is equipped with a high-energy (up to 15 keV) high-resolution (meV) hemispherical analyzer with a microchannel plate and CCD detector system with SpecsLab Prodigy and CasaXPS software. Additional user facilities include a thin-film laboratory for sample preparation and a workstation for on-site data processing. In this article, the design details of the beamline, other facilities and some recent scientific results are described.

2.
3.
ACS Appl Mater Interfaces ; 7(18): 9336-48, 2015 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-25918822

RESUMEN

The present study concerns development of an efficient alcohol sensor by controlling the stoichiometry, length, and wall thickness of electrochemically grown TiO2 nanotube array for its use as the sensing layer. Judicious variation of H2O content (0, 2, 10 and 100% by volume) in the mixed electrolyte comprising ethylene glycol and NH4F resulted into the desired variation of stoichiometry. The sensor study was performed within the temperature range of 27 to 250 °C for detecting the alcohols in the concentration range of 10-1000 ppm. The nanotubes grown with the electrolyte containing 2 vol % H2O offered the maximum response magnitude. For this stoichiometry, variation of corresponding length (1.25-2.4 µm) and wall thickness (19.8-9 nm) of the nanotubes was achieved by varying the anodization time (4-16 h) and temperatures (42-87 °C), respectively. While the variation of length influenced the sensing parameters insignificantly, the best response magnitude was achieved for ∼13 nm wall thickness. The underlying sensing mechanism was correlated with the experimental findings on the basis of structural parameters of the nanotubes.

5.
Neoplasma ; 61(6): 747-57, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25150320

RESUMEN

Carcinoma of oral cavity have a high risk of recurrence after initial treatment with surgery, radiotherapy, surgery with adjuvant radiotherapy, or radio-chemotherapy.The present study investigated the changes in expression, activity and regulation of matrix metalloproteinases (MMP) -2 and -9 in oral squamous cell carcinoma (OSCC) which might help to ascertain the invasive potential of the tumor . Tumor tissues and adjacent normal tissues of OSCC patients [N,37; either sex; 20-70 yrs] were subjected to clinico-pathology, histopathology and TNM grading. The enzyme activity and associated signalling was observed with gelatin zymography, immunohistochemistry, ELISA, western blot and semi quantitative reverse transcriptase PCR. OSCC tissues were observed with elevated MMP-9 activity, enhanced expression of fibronectin (FN), phosphorylated focal adhesion kinase (FAK Try 397), phosphatidyl inositol 3­kinase (PI3K), protein kinase B (AKT) and reduced expression of tissue inhibitor of metalloproteinase- 1(TIMP-1) than the control tissues.OSCC patients elicited a predominance of MMP-9 activity via up regulated FAK/PI3K/AKT pathway. A routine MMP-9 analysis may ascertain the invasiveness of the tumor and therefore may be professed as a suitable biomarker for metastatic potential of oral cancer.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Neoplasias de la Boca/enzimología , Adulto , Anciano , Femenino , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Humanos , India , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/patología , Estadificación de Neoplasias , Proteínas Proto-Oncogénicas c-akt/metabolismo
6.
Phys Rev Lett ; 113(4): 042002, 2014 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-25105609

RESUMEN

We present the first model-independent measurement of the absolute branching fraction of the Λ(c)(+) → pK(-)π(+) decay using a data sample of 978 fb(-1) collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The number of Λ(c)(+) baryons is determined by reconstructing the recoiling D((*)-) pπ(+) system in events of the type e(+)e(-) → D((*)-) pπ(+)Λ(c)(+). The branching fraction is measured to be B(Λ(c)(+) → pK(-)π(+)) = (6.84 ± 0.24(-0.27)(+0.21))%, where the first and second uncertainties are statistical and systematic, respectively.

7.
Phys Rev Lett ; 112(11): 111801, 2014 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-24702349

RESUMEN

We observe D(0)-D(0) mixing in the decay D(0) → K+π- using a data sample of integrated luminosity 976 fb(-1) collected with the Belle detector at the KEKB e+e- asymmetric-energy collider. We measure the mixing parameters x'(2) = (0.09 ± 0.22) × 10(-3) and y'=(4.6 ± 3.4) × 10(-3) and the ratio of doubly Cabibbo-suppressed to Cabibbo-favored decay rates R(D) = (3.53 ± 0.13) × 10(-3), where the uncertainties are statistical and systematic combined. Our measurement excludes the no-mixing hypothesis at the 5.1 standard deviation level.

8.
Phys Rev Lett ; 111(3): 032001, 2013 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-23909309

RESUMEN

We report measurements of B→χ(c1)γK and χ(c2)γK decays using 772×10(6) BB[over ¯] events collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. Evidence of a new resonance in the χ(c1)γ final state is found with a statistical significance of 3.8σ. This state has a mass of 3823.1±1.8(stat)±0.7(syst) MeV/c(2), a value that is consistent with theoretical expectations for the previously unseen 1(3)D(2) cc[over ¯] meson. We find no other narrow resonance and set upper limits on the branching fractions of the X(3872)→χ(c1)γ and χ(c2)γ decays.

9.
Phys Rev Lett ; 110(25): 252002, 2013 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-23829730

RESUMEN

The cross section for ee+ e- → π+ π- J/ψ between 3.8 and 5.5 GeV is measured with a 967 fb(-1) data sample collected by the Belle detector at or near the Υ(nS) (n = 1,2,…,5) resonances. The Y(4260) state is observed, and its resonance parameters are determined. In addition, an excess of π+ π- J/ψ production around 4 GeV is observed. This feature can be described by a Breit-Wigner parametrization with properties that are consistent with the Y(4008) state that was previously reported by Belle. In a study of Y(4260) → π+ π- J/ψ decays, a structure is observed in the M(π(±)J/ψ) mass spectrum with 5.2σ significance, with mass M = (3894.5 ± 6.6 ± 4.5) MeV/c2 and width Γ = (63 ± 24 ± 26) MeV/c2, where the errors are statistical and systematic, respectively. This structure can be interpreted as a new charged charmoniumlike state.

10.
Microsc Microanal ; 18(5): 1077-87, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23095447

RESUMEN

Optical and scanning electron microscopy (SEM) of red blood cells (RBCs) of common carp, Cyprinus carpio, inhabiting a polluted lake in Northeast India revealed a number of abnormalities. About 7% of the RBC showed the presence of a micronucleus, besides the presence of some bi-nucleated and abnormally shaped nuclei. RBCs, white blood cells, and hemoglobin content were found to be reduced significantly as compared to the control. SEM showed the presence of spherocytes, early stages of echinocytes, cytoplasmic blebbing, erythrocytes with contraction from one side, abnormal shape of erythrocytes (hexagonal/pentagonal/tetragonal), development of lobopodial projections, cell rupture, membrane internalization, and formation of ring-shaped RBC. Energy dispersive X-ray spectroscopy (EDS) showed the presence of a considerable percentage of silicon and lead in erythrocytes of the fish collected from the polluted lake, in contrast to a negligible concentration of the two elements in control fish. Significance of the study in relation to fish health in a polluted body of water and the importance of SEM, EDS, and light microscopy in utilizing hematological parameters as pollution indicators are discussed.


Asunto(s)
Carpas/sangre , Monitoreo del Ambiente , Eritrocitos/citología , Animales , Recuento de Eritrocitos , Eritrocitos/química , Eritrocitos/metabolismo , Hemoglobinas/análisis , Hemoglobinas/metabolismo , Lagos/análisis , Microscopía , Contaminación del Agua
11.
Scand J Immunol ; 76(6): 528-40, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22924656

RESUMEN

To study the effects of gentamicin in combination with ascorbic acid on septic arthritis, mice were infected with Staphylococcus aureus (S. aureus) and treated with gentamicin, which was given at 5 mg/kg after 24 h of infection, followed by ascorbic acid, given at 20 mg/kg body weight after 2 h of gentamicin treatment. Mice were sacrificed at 3, 9, 15 days post-infection (dpi). Combined treatment of infected mice with gentamicin and ascorbic acid eradicated the bacteria from the blood, spleen and synovial tissue and showed a significant gross reduction in arthritis, reduced serum levels of tumour necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ). S. aureus-infected mice have demonstrated the disturbed antioxidant status measured in terms of cellular antioxidants like reduced glutathione and antioxidant enzymes such as superoxide dismutase (SOD) and catalase. The same were ameliorated when the animals were co-treated with gentamicin along with ascorbic acid.


Asunto(s)
Artritis Infecciosa/tratamiento farmacológico , Ácido Ascórbico/administración & dosificación , Gentamicinas/administración & dosificación , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Animales , Artritis Infecciosa/etiología , Artritis Infecciosa/inmunología , Células Cultivadas , Progresión de la Enfermedad , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , Interferón gamma/sangre , Masculino , Ratones , Estrés Oxidativo/efectos de los fármacos , Infecciones Estafilocócicas/complicaciones , Infecciones Estafilocócicas/inmunología , Superóxido Dismutasa/metabolismo , Factor de Necrosis Tumoral alfa/sangre
12.
Microsc Res Tech ; 74(11): 998-1005, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21509904

RESUMEN

The present communication reports the ultra structural abnormalities in sperm of a fish species Cyprinus carpio inhabiting a polluted lake, Umiam in North-East India. Transmission electron microscopy (TEM) revealed absence of differentiation between head and midpiece (neck) of some sperm while scanning electron microscopy (SEM) showed some sperm tails with highly reduced length and some sperm with folded tail. Abnormal shape of some sperm head was also revealed by Scanning electron microscopy. Detachment of membrane from some parts of the sperm head and an outward expansion of the same was observed from Transmission electron micrographs of transverse section of sperm head. The well developed mitochondria surrounding the cytoplasmic channel in the sperm tail, as observed in control were found to be drastically disorganized in fish inhabiting the polluted lake. The study suggests that the fish C. carpio inhabiting the polluted lake Umiam is under severe stress as far as its male reproductive system is concerned. The study further suggests that Electron microscopic approach is extremely important in the assessment of adverse effects of environmental pollution on fish tissue. Microsc. Res. Tech. 2011. © 2011 Wiley Periodicals, Inc.


Asunto(s)
Carpas/fisiología , Exposición a Riesgos Ambientales , Espermatozoides/ultraestructura , Animales , Agua Dulce , India , Masculino , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión
13.
J Food Sci Technol ; 47(6): 693-6, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23572709

RESUMEN

Level of inclusion of chicken blood plasma (CBP) in the preparation of cakes was assessed in respect of certain physico-chemical quality traits. The cakes were prepared with and without added flavour. In each group, seven cakes were prepared from 0 (control) to 60% level of inclusion of CBP with 10% interval. The cakes at 40% level of incorporation of CBP recorded highest visual grades for colour and consistency. There was gradual rise in cake volume up to 40% level and on further increase in level of inclusion of CBP resulted into subsequent fall in cake volumes. The pH of cakes did not differ significantly up to 20% level but it increased beyond 20%. The moisture, total ash and crude protein contents of cakes exhibited an increasing trend from 0 to 60% level of inclusion of CBP. The ether extract of cakes showed a gradual decrease at increased level of inclusion of CBP. There was no significant effect of flavour for all the parameters studied. Based on the overall results, it may be concluded that CBP could be successfully used up to 30% level of inclusion for value addition in egg products.

14.
J Environ Radioact ; 99(10): 1566-71, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18258344

RESUMEN

Radiocarbon measurements were made in the water column of the Arabian Sea and the equatorial Indian Ocean during 1994, 1995 and 1997 to assess the temporal variations in bomb 14C distribution and its inventory in the region with respect to GEOSECS measurements made during 1977-1978. Four GEOSECS stations were reoccupied (three in the Arabian Sea and one in the equatorial Indian Ocean) during this study, with all of them showing increased penetration of bomb 14C along with decrease in its surface water activity. The upwelling rates derived by model simulation of bomb 14C depth profile using the calculated exchange rates ranged from 3 to 9 m a(-1). The western region of the Arabian Sea experiencing high wind-induced upwelling has higher estimated upwelling rates. However, lower upwelling rates obtained for the stations occupied during this study could be due to reduced 14C gradient compared to that during GEOSECS.


Asunto(s)
Bombas (Dispositivos Explosivos) , Agua de Mar/análisis , Contaminación Radiactiva del Agua/análisis , Radioisótopos de Carbono/análisis , Geografía , Océano Índico , Monitoreo de Radiación/métodos
15.
Ecotoxicol Environ Saf ; 69(3): 556-61, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17328951

RESUMEN

Screen-printed electrodes (SPEs) containing immobilized acetylcholine esterase (AChE) enzyme were used for the electrochemical determination of organophosphorous (OP) and carbamate pesticides. The extent of AChE deactivation by the pesticide was determined in the presence of acetylcholine (AChCl) substrate. The unique nature of this approach lies in the enzyme immobilization procedure in which AChE was attached to the SPE by in situ bulk polymerization of acrylamide to ensure efficient adherence within the membrane with minimal losses in enzyme activity. Responses were observed for the pesticides Monocrotophos, Malathion, Metasystox and Lannate over the concentration range 0-10 ppb (microg L(-1)).


Asunto(s)
Acetilcolinesterasa/metabolismo , Enzimas Inmovilizadas/antagonistas & inhibidores , Plaguicidas/análisis , Carbamatos/toxicidad , Inhibidores de la Colinesterasa/análisis , Electroquímica/métodos , Electrodos , Concentración de Iones de Hidrógeno , Cinética , Plaguicidas/toxicidad
16.
Diabetologia ; 49(5): 1097-105, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16541279

RESUMEN

AIMS/HYPOTHESIS: The goal of this investigation was to determine whether there are sex-related differences in the development of cardiomyocyte dysfunction in prediabetic, insulin-resistant animals. MATERIALS AND METHODS: Male and female rats were maintained on a high-sucrose diet for 5-11 weeks, and mechanical properties of isolated ventricular myocytes were measured by high-speed video edge detection. Several in vitro interventions were used to manipulate intracellular Ca(2+) in order to determine whether altered Ca(2+) availability contributes to the cardiomyocyte dysfunction. RESULTS: Myocyte shortening and relengthening were significantly slower in sucrose-fed (insulin-resistant) males than in starch-fed (normal) male rats, whereas only relengthening was slower in sucrose-fed females when compared with normal females. Areas under the contraction and relaxation phases for sucrose-fed males were also significantly larger than in diet-matched females, and the slowed cardiomyocyte mechanics appeared earlier in males (7 vs 10 weeks). Prolonged relaxation was ameliorated in myocytes from sucrose-fed female rats by all interventions (i.e. 10(-8) mol/l isoprenaline, elevated extracellular Ca(2+), and higher rates of stimulation). Twice as much extracellular Ca(2+) (4 mmol/l) was required to restore normal time courses of contraction and relaxation in sucrose-fed males than in females, and mechanical responses to higher frequency stimulation remained impaired (slower) in some myocytes from sucrose-fed male rats. CONCLUSIONS/INTERPRETATION: These data suggest that in myocytes from insulin-resistant rats altered Ca(2+) handling occurs, contributing to abnormal excitation-contraction coupling; female rats seem to have some cardioprotection during early stages in the progression towards type 2 diabetes. Females show delayed onset and milder abnormalities in metabolic status and cardiomyocyte function, but with a much tighter temporal coupling of these dysfunctions.


Asunto(s)
Corazón/fisiología , Corazón/fisiopatología , Resistencia a la Insulina , Células Musculares/citología , Animales , Fenómenos Biomecánicos , Dieta , Sacarosa en la Dieta/farmacología , Femenino , Corazón/efectos de los fármacos , Ventrículos Cardíacos/citología , Ventrículos Cardíacos/efectos de los fármacos , Masculino , Células Musculares/efectos de los fármacos , Miocardio/citología , Miocardio/patología , Ratas , Caracteres Sexuales
17.
Biomed Environ Sci ; 17(3): 309-14, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15602828

RESUMEN

OBJECTIVE: Fenvalerate (20% EC) is a synthetic pyrethroid, which is commonly used in India by farmers for the protection of many food and vegetable crops against a wide variety of insects. However, its inhalation toxicity data is very limited in the literature due to the fact that the exposure levels associated with these effects were usually not reported. Hence, inhalation exposure was carried out to investigate the hepatotoxic effects. METHOD: Adult male rats were exposed to fen for 4 h/day, 5 days a week for 90 days by using Flow Past Nose Only Inhalation Chamber. Sham treated control rats were exposed to compressed air in the inhalation chamber for the same period. RESULTS: The results indicated hepatomegaly, increased activities of serum clinical enzymes (indicative of liver damage/dysfunction) along with pronounced histopathological damage of liver. CONCLUSION: The hepatotoxic potential of formulated Fen (20% EC) in rats exposed by nose only inhalation is being reported for the first time and warrant adequate safety measures for human beings exposed to this insecticide, particularly by inhalation route.


Asunto(s)
Exposición por Inhalación , Insecticidas/toxicidad , Hígado/efectos de los fármacos , Hígado/patología , Piretrinas/toxicidad , Animales , Insecticidas/administración & dosificación , Hígado/enzimología , Masculino , Nitrilos , Tamaño de los Órganos/efectos de los fármacos , Piretrinas/administración & dosificación , Ratas , Ratas Wistar
18.
Gut ; 53(1): 62-9, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14684578

RESUMEN

BACKGROUND AND AIMS: The general concept is that as Vibrio cholerae is not invasive, it mediates a non-inflammatory type of infection. This is being re-evaluated based on available data that natural cholera infection or cholera toxin induces a Th2-type of immune profile and stimulates the humoral immune response, innate cells, and mediators in the host. METHODS: To perform a comprehensive analyses of the inflammatory components, we studied mucosal biopsies from patients, both adults and children with acute watery diarrhoea caused by V cholerae O1 and O139. Patients with cholera, adults (n = 30) and children (n = 18), as well as healthy controls (n = 24) were studied. Histochemical, immunohistochemical, and ultrastructural studies were carried out to elucidate the contribution of the different factors using paraffin and frozen duodenal and/or rectal sections as appropriate. Samples were collected during the acute stage and during early and/or late convalescence. RESULTS: Following natural cholera infection, patients responded with increases in neutrophil polymorphs during the acute stage (p<0.001) compared with healthy controls whereas mucosal mast cells (MMC) (p = 0.008) and eosinophils (p = 0.034) increased in the gut during convalescence. Electron microscopic analyses of duodenal biopsies from adult patients showed increased piecemeal degranulation in both MMC and eosinophils and accumulation of lipid bodies in MMC. Duodenal biopsies from V cholerae O1 infected patients showed upregulation of myeloperoxidase, lactoferrin, PGHS-1, SCF, tryptase, tumour necrosis factor alpha, alpha-defensin, and eotaxin during the acute stage and chymase, interleukin 3 and major basic protein during convalescence. CONCLUSION: We have shown that innate cells and their mediators are upregulated in acute watery diarrhoea. These cells and factors of the innate arm may be important in the host's defence against cholera. Such effects may need to be simulated in a vaccine to achieve long lasting protection from cholera.


Asunto(s)
Cólera/inmunología , Mediadores de Inflamación/metabolismo , Mucosa Intestinal/inmunología , Vibrio cholerae O139/patogenicidad , Vibrio cholerae O1/patogenicidad , Enfermedad Aguda , Adolescente , Adulto , Preescolar , Cólera/metabolismo , Cólera/patología , Duodeno/inmunología , Duodeno/metabolismo , Duodeno/ultraestructura , Eosinófilos/ultraestructura , Femenino , Humanos , Mucosa Intestinal/microbiología , Mucosa Intestinal/ultraestructura , Recuento de Leucocitos , Masculino , Mastocitos/ultraestructura , Microscopía Electrónica , Persona de Mediana Edad , Neutrófilos/patología , Regulación hacia Arriba
19.
Int J Gynecol Cancer ; 13(5): 626-32, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14675346

RESUMEN

Visual inspection of the cervix after application of 3-5% acetic acid (VIA) is a potential alternative to cytology for screening in low-resource countries. The present study evaluated the performance of VIA, magnified visual inspection after application of acetic acid (VIAM), and cytology in the detection of high-grade cervical cancer precursor lesions in Kolkata (Calcutta) and suburbs in eastern India. Trained health workers with college education concurrently screened 5881 women aged 30-64 years with VIA, VIAM, and conventional cervical cytology. Detection of well-defined, opaque acetowhite lesions close to the squamocolumnar junction; well-defined, circumorificial acetowhite lesions; or dense acetowhitening of ulceroproliferative growth on the cervix constituted a positive VIA or VIAM. Cytology was considered positive if reported as mild dysplasia or worse lesions. All screened women (N = 5881) were evaluated by colposcopy, and biopsies were directed in those with colposcopic abnormalities (N = 1052, 17.9%). The final diagnosis was based on histology (if biopsies had been taken) or colposcopic findings, which allowed direct estimation of sensitivity, specificity, and predictive values. Moderate or severe dysplasia or carcinoma in situ (CIN 2-3 disease) was considered as true positive disease for the calculation of sensitivity, specificity, and predictive values of screening tests. 18.7%, 17.7% and 8.2% of the women tested positive for VIA, VIAM, and cytology. One hundred twenty two women had a final diagnosis of CIN 2-3 lesions. The sensitivities of VIA and VIAM to detect CIN 2-3 lesions were 55.7% and 60.7%, respectively; the specificities were 82.1% and 83.2%, respectively. The sensitivity and specificity of cytology were 29.5% and 92.3%, respectively. All the tests were associated with negative predictive values above 98%. VIA and VIAM had significantly higher sensitivity than cytology in our study; the specificity of cytology was higher than that of VIA and VIAM.


Asunto(s)
Ácido Acético , Examen Físico/normas , Displasia del Cuello del Útero/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Adulto , Colposcopía , Estudios Transversales , Femenino , Humanos , India , Tamizaje Masivo/métodos , Tamizaje Masivo/normas , Persona de Mediana Edad , Examen Físico/métodos , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Neoplasias del Cuello Uterino/patología , Frotis Vaginal , Displasia del Cuello del Útero/patología
20.
Epidemiol Infect ; 129(1): 107-12, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12211576

RESUMEN

Genomic variability within the sequences of VP1/2A junction among polioviruses from across the globe has revealed the existence of several endemic genotypes and their epidemiological inter-relationships; but such data on Indian isolates are scanty. The present work was intended to ascertain the persistence and transmission pattern of different genotypes of wild type 1 polioviruses circulating in India. Forty-eight wild type 1 poliovirus isolates obtained from different parts of India during 1996-8 were subjected to RT-PCR and nucleotide sequencing using M13 tailed primers. A 293 base pair region was amplified and sequenced for genetic variation study. Considering the 15% divergence of the sequences from Sabin 1, the isolates from six different states of India confirmed a single dominant genotype 4. Phylogenetic analysis revealed the circulation and active inter-state transmission of many genetically distinct strains of wild poliovirus type 1 belonging to genotype 4. This warrants the need for insisting on more efficient surveillance mechanisms so as to assess the impact of an extensive pulse polio immunization programme in India.


Asunto(s)
Cápside/genética , Cisteína Endopeptidasas/genética , Poliovirus/genética , Proteínas Virales , Secuencia de Aminoácidos , Cápside/química , Proteínas de la Cápside , Cisteína Endopeptidasas/química , Humanos , India , Datos de Secuencia Molecular , Poliomielitis/prevención & control , Poliomielitis/transmisión , Poliovirus/clasificación
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