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1.
Phys Rev Lett ; 125(13): 132501, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33034500

RESUMO

We report the first observation of two wobbling bands in ^{183}Au, both of which were interpreted as the transverse wobbling (TW) band but with different behavior of their wobbling energies as a function of spin. It increases (decreases) with spin for the positive (negative) parity configuration. The crucial evidence for the wobbling nature of the bands, dominance of the E2 component in the ΔI=1 transitions between the partner bands, is provided by the simultaneous measurements of directional correlation from the oriented states ratio and the linear polarization of the γ rays. Particle rotor model calculations with triaxial deformation reproduce the experimental data well. A value of spin, I_{m}, has been determined for the observed TW bands below which the wobbling energy increases and above which it decreases with spin. The nucleus ^{183}Au is, so far, the only nucleus in which both the increasing and the decreasing parts are observed and thus gives the experimental evidence of the complete transverse wobbling phenomenon.

2.
Phys Rev Lett ; 115(17): 172501, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26551106

RESUMO

Excited states of the neutron-rich nuclei (97,99)Rb were populated for the first time using the multistep Coulomb excitation of radioactive beams. Comparisons of the results with particle-rotor model calculations provide clear identification for the ground-state rotational band of (97)Rb as being built on the πg(9/2) [431] 3/2(+) Nilsson-model configuration. The ground-state excitation spectra of the Rb isotopes show a marked distinction between single-particle-like structures below N=60 and rotational bands above. The present study defines the limits of the deformed region around A∼100 and indicates that the deformation of (97)Rb is essentially the same as that observed well inside the deformed region. It further highlights the power of the Coulomb-excitation technique for obtaining spectroscopic information far from stability. The (99)Rb case demonstrates the challenges of studies with very short-lived postaccelerated radioactive beams.

4.
Fungal Genet Biol ; 79: 118-24, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26092798

RESUMO

Understanding the cellular organization and biology of fungal pathogens requires accurate methods for genomic integration of mutant alleles or fluorescent fusion-protein constructs. In Zymoseptoria tritici, this can be achieved by integrating of plasmid DNA randomly into the genome of this wheat pathogen. However, untargeted ectopic integration carries the risk of unwanted side effects, such as altered gene expression, due to targeting regulatory elements, or gene disruption following integration into protein-coding regions of the genome. Here, we establish the succinate dehydrogenase (sdi1) locus as a single "soft-landing" site for targeted ectopic integration of genetic constructs by using a carboxin-resistant sdi1(R) allele, carrying the point-mutation H267L. We use various green and red fluorescent fusion constructs and show that 97% of all transformants integrate correctly into the sdi1 locus as single copies. We also demonstrate that such integration does not affect the pathogenicity of Z. tritici, and thus the sdi1 locus is a useful tool for virulence analysis in genetically modified Z. tritici strains. Furthermore, we have developed a vector which facilitates yeast recombination cloning and thus allows assembly of multiple overlapping DNA fragments in a single cloning step for high throughput vector and strain generation.


Assuntos
Ascomicetos/genética , Loci Gênicos , Genética Microbiana/métodos , Biologia Molecular/métodos , Mutagênese Insercional/métodos , Recombinação Genética , Expressão Gênica , Succinato Desidrogenase/genética
5.
Phys Rev Lett ; 108(6): 062701, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22401060

RESUMO

The neutron-rich nuclei 94,96Kr were studied via projectile Coulomb excitation at the REX-ISOLDE facility at CERN. Level energies of the first excited 2(+) states and their absolute E2 transition strengths to the ground state are determined and discussed in the context of the E(2(1)(+)) and B(E2;2(1)(+)→0(1)(+)) systematics of the krypton chain. Contrary to previously published results no sudden onset of deformation is observed. This experimental result is supported by a new proton-neutron interacting boson model calculation based on the constrained Hartree-Fock-Bogoliubov approach using the microscopic Gogny-D1M energy density functional.

6.
Phys Rev Lett ; 105(25): 252501, 2010 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-21231582

RESUMO

The "island of inversion" nucleus 32 Mg has been studied by a (t, p) two neutron transfer reaction in inverse kinematics at REX-ISOLDE. The shape coexistent excited 0+ state in 32 Mg has been identified by the characteristic angular distribution of the protons of the Δ L=0 transfer. The excitation energy of 1058 keV is much lower than predicted by any theoretical model. The low γ-ray intensity observed for the decay of this 0+ state indicates a lifetime of more than 10 ns. Deduced spectroscopic amplitudes are compared with occupation numbers from shell-model calculations.

7.
Indian J Otolaryngol Head Neck Surg ; 58(2): 202-4, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23120289

RESUMO

Hypohydrotic (Anhidrotic) Ectodermal dysplasia is a rare hereditary genodermatosis characterized by a triad of defects including hypohidrosis hypotrichosis and anomalous dentition. Mainly ectodermal structures are involved such as epidermis and its annexes (hair & nails), although non-ecotodermal tissue may also became involved(1). ENT involvement in such cases is a consequence of the defect involving the eccrine and sebaceous glands. A case of a 3 years old female child suffering from hypohidrotic ectodermal dysplasia with features of Atrophic Rhinitis from infancy & early childhood is reported here. Management of these patients is mainly supportive and otolaryngologist is a vital component of the health care team managing such patients.

8.
Toxicol Lett ; 145(3): 231-7, 2003 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-14580894

RESUMO

The involvement of frequency-dependent depression (FDD) of synaptic transmission for the depressant action of the Ptychodiscus brevis toxin (PbTx) was investigated in neonatal rat spinal cord in vitro. The stimulation of a dorsal root by train of pulses (five stimuli) at different frequencies evoked potentials in the ventral root (monosynaptic reflex, MSR). Amplitude of the fifth response as percent of first response at 0.1, 0.2, 0.5, 1.0 and 2.0 Hz were 90, 80, 75, 70 and 50%, respectively. In Mg2+-free medium, PbTx depressed the MSR and also enhanced the FDD in a concentration-dependent manner. Further, the PbTx-induced depression can well be correlated with the enhancement of FDD (r=0.98). In the presence of Mg2+ (1.3 mM), the FDD was greater than that in the absence of Mg2+. But in the presence of Mg2+ PbTx did not alter FDD, even though there was 25% depression at 28 microM (significantly lesser than in Mg2+-free medium). The results indicate that the Mg2+-sensitive component of PbTx-induced depression of MSR is mediated via the neuronal systems involving FDD.


Assuntos
Ciclopentanos/farmacologia , Compostos Organofosforados/farmacologia , Reflexo Monosináptico/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Depressão Química , Estimulação Elétrica , Técnicas In Vitro , Magnésio/farmacologia , Ratos , Ratos Endogâmicos , Raízes Nervosas Espinhais/efeitos dos fármacos
9.
J Assoc Physicians India ; 50: 879-81, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12126339

RESUMO

OBJECTIVE: To study the changing incidence of blood transfusion-related viral infections consequent to compulsory screening of blood and greater awareness of the problem, over the last five years. METHODS: This is a cross-sectional study carried out at Medical College, Calcutta. Three groups each consisting of 100 subjects were selected for this study. Group A comprised multiple transfused patients who have also received transfusion before 1995. Group B comprised patients who had received transfusions only since 1995. Group C comprised of control patients who have never been transfused. The incidence of HBsAg +ve, anti-HCV +ve and HIV +ve cases were calculated and expressed as percentages and compared using the chi square test. RESULTS: The incidences of HBsAg +ve and anti-HCV +ve cases in the three groups were 20% and 16% in Group A, 7% and 6% in Group B and 4% and 2% in Group C. The difference between Group A and Group B were statistically significant. CONCLUSION: The incidence of HBsAg and anti-HCV positive cases among the multi-transfused has decreased over the last five years.


Assuntos
Hepatite B/etiologia , Hepatite C/etiologia , Reação Transfusional , Adolescente , Transfusão de Sangue/tendências , Criança , Estudos Transversais , Feminino , Hepatite B/sangue , Hepatite B/epidemiologia , Antígenos de Superfície da Hepatite B/sangue , Hepatite C/sangue , Hepatite C/epidemiologia , Humanos , Índia/epidemiologia , Masculino
10.
Toxicol Lett ; 128(1-3): 177-83, 2002 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-11869828

RESUMO

Effects of Ptychodiscus brevis toxin (PbTx) analogs on the spinal synaptic transmission in neonatal rats in vitro were evaluated. PbTx1/PbTx2 had aromatic groups and PbTx3/PbTx4 had aliphatic groups. All the analogs depressed monosynaptic reflex (MSR) and polysynaptic reflex (PSR) in a concentration-dependent manner. The maximal depression of MSR (75% from initial) and PSR (96%) was at 84 microM for PbTx1. Concentration to produce 25% inhibition from initial (IC25) by PbTx1 for MSR and PSR was < or =2.8 microM. The maximal depression of MSR (80%) was at 96 microM and PSR (100%) was at 32 microM by PbTx2. IC25 for MSR and PSR were 5.5 microM and <3.2 microM, respectively. PbTx3 decreased MSR by 25% maximally (=IC25) at 36 microM. The depression of PSR fluctuated and was maximal (75%) at 108 microM and IC25 was 6.2 microM. PbTx4 depressed MSR and PSR at the maximum of 35% at 32 microM and IC25 for MSR was 8.3 microM and for PSR was 35 microM. Rank order of potency of toxins for depressing MSR was PbTx1>PbTx2>>PbTx4>PbTx3; and for PSR it was PbTx2>PbTx1>PbTx3>>PbTx4. Results indicate that the toxins having aromatic groups exhibited greater neurotoxicity.


Assuntos
Toxinas Marinhas/toxicidade , Medula Espinal/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Depressão Química , Dinoflagellida/química , Dinoflagellida/metabolismo , Feminino , Técnicas In Vitro , Masculino , Oxocinas , Ratos , Medula Espinal/fisiologia
12.
Int J Tuberc Lung Dis ; 5(7): 604-10, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11467366

RESUMO

SETTING: The public health sector of Bangladesh. OBJECTIVE: To assess gender differences in access to tuberculosis diagnosis and in tuberculosis treatment outcome in Bangladesh. METHODS: Information on the age and sex of a sample of patients in 1997 was collected from out-patient registers and tuberculosis laboratory and treatment registers in 59 thanas in three divisions in Bangladesh. RESULTS: The female/male ratio was 0.79 among 42,877 out-patients with respiratory complaints, 0.51 among 5,665 tuberculosis suspects undergoing sputum smear microscopy, 0.36 among 869 tuberculosis suspects with positive sputum smears, and 0.35 among 5,632 patients registered for tuberculosis treatment. Treatment was successful (cured or treatment completed) in 86% of female and 84% of male patients. CONCLUSION: Women in Bangladesh appear to have less access to public out-patient clinics than men, and if they present with respiratory symptoms they are less likely to undergo sputum smear examination. If examined, women are less likely than men to be smear-positive. No gender bias was observed in tuberculosis treatment outcome. It is recommended to focus further research on exploration of sex differences in the incidence of respiratory conditions, identification of constraints among women in accessing out-patient clinics and verification of the quality of sputum submitted by women for examination.


Assuntos
Tuberculose/diagnóstico , Tuberculose/terapia , Adolescente , Adulto , Idoso , Bangladesh , Criança , Atenção à Saúde , Terapia Diretamente Observada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Escarro/microbiologia
13.
FEMS Microbiol Lett ; 188(1): 47-53, 2000 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10867233

RESUMO

L1 is a lysogenic phage of mycobacteria, which along with L5 and D29 constitute a closely linked family of homoimmune mycobacteriophages. These phages can be potentially used for genetic engineering of mycobacteria and diagnosis of mycobacterial infection. The effectiveness of such phage based systems depends on the efficiency with which they infect and grow within target cells. While working with phage L1c1ts which is a temperature sensitive mutant of phage L1, we observed that high yielding phage stocks were generated by repeated passage through the host, Mycobacterium smegmatis. A plaque purified mutant L1-P2, obtained from one such high yielding stock, when analyzed further was found to infect host cells with increased efficiency. The DNA obtained from L1-P2 was examined by restriction digestion, and it was observed that spontaneous loss of DNA fragment from the right arm, which encodes early regulatory factors, had occurred. It has been further demonstrated that the high yielding property of the mutant phage could be utilized to increase the sensitivity of mycobacteriophage-based detection systems.


Assuntos
Mutação , Micobacteriófagos/crescimento & desenvolvimento , Micobacteriófagos/genética , Mycobacterium smegmatis/virologia , Adsorção , Contagem de Colônia Microbiana , DNA Viral/análise , Lisogenia , Mycobacterium smegmatis/crescimento & desenvolvimento , Mycobacterium smegmatis/isolamento & purificação , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/isolamento & purificação , Mycobacterium tuberculosis/virologia , Mapeamento por Restrição , Ensaio de Placa Viral
14.
Indian J Biochem Biophys ; 36(1): 51-4, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10549161

RESUMO

The permissible limit of arsenic content in drinking water is 0.05 ppm, whereas, in many parts of West Bengal the arsenic level in drinking water is 0.1 ppm, frequently 0.3 ppm and even 3.0 ppm, though rarely. In order to assess possible risk to brain function by drinking such water, rats were given arsenic mixed in drinking water at the above four concentrations for 40 days. There was increased lipid peroxidation at all doses of arsenic, including the 'permissible limit', decrease in glutathione level, superoxide dismutase and glutathione reductase activities, indicating the free-radical-mediated degeneration of brain.


Assuntos
Intoxicação por Arsênico/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Humanos , Índia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Concentração Máxima Permitida , Ratos , Ratos Sprague-Dawley , Abastecimento de Água/análise
15.
Plasmid ; 41(2): 135-40, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10087218

RESUMO

Escherichia coli-mycobacteria shuttle vectors, derived from pAL5000 (a mycobacterial plasmid) and pUC19, were frequently found to undergo structural alterations due to transposition of IS1096, a Mycobacterium smegmatis transposable element, at a cluster of sites located within a small region of 60 bp, immediately upstream of a kanamycin resistance gene present in these vectors. The structural alterations led to deletion of large regions of the vector which, in several cases, were found to extend into the ORF2 (RepB) coding sequences of the pAL5000 replication region without affecting its replication capability. This suggests that the entire ORF2 coding sequences of the pAL5000 replication region may not be essential for replication of pAL5000-derived vectors. The deletion derivatives, which contain the minimal sequences required for replication and selection in mycobacteria, were found to be structurally stable and therefore these could be potentially used as stable vector systems for the transformation of mycobacteria.


Assuntos
Elementos de DNA Transponíveis , Escherichia coli/genética , Vetores Genéticos , Mycobacterium smegmatis/genética , Sequência de Bases , DNA Bacteriano , Dados de Sequência Molecular
16.
J Indian Med Assoc ; 96(8): 236-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9830289

RESUMO

A 5-year sentinel surveillance of diphtheria from 1989 to 1993 was undertaken at a rural medical college hospital. No significant change in the number of diphtheria cases was observed in spite of sustained high level of diphtheria, pertussis, tetanus vaccine-3 doses (DPT3) coverage. Most of the diphtheria cases occurred during July to November. Age distribution of diphtheria cases showed that more than 75% occurred above 2 years age (except in 1989) and around 65% cases above 3 years age. The age shift in diphtheria signified success of primary diphtheria immunisation, as well as indicated the lack of coverage with booster doses at appropriate ages. Because of high coverage with primary diphtheria immunisation there was decrease in circulating toxigenic C diphtheriae resulting in less natural boosting of antibody titre. Thus, in absence of booster immunisation, the older children and adults were more vulnerable to diphtheria. The findings of the study justified the need of emphasising importance of booster diphtheria immunisation at appropriate ages for effective control of diphtheria.


Assuntos
Difteria/prevenção & controle , Adulto , Fatores Etários , Criança , Pré-Escolar , Difteria/epidemiologia , Toxoide Diftérico/administração & dosagem , Feminino , Humanos , Imunização , Imunização Secundária , Índia/epidemiologia , Lactente , Recém-Nascido , Estudos Prospectivos , Estudos Retrospectivos , Estações do Ano , Vigilância de Evento Sentinela
17.
Phys Rev C Nucl Phys ; 54(6): R2820-R2822, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9971721
18.
J Appl Toxicol ; 16(6): 497-500, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8956095

RESUMO

Effect of diisopropylphosphorofluoridate (DFP), an irreversible cholinesterase (ChE) inhibitor, on compound action potential (CAP) of sciatic nerve in vitro was examined. Further, the role of cholinesterase reactivator (1 acetyl-4-hydroxy imino methyl pyridinium bromide; SPK-3) in reversing DFP-induced changes was also evaluated. Diisopropylphosphorofluoridate produced a dose-dependent depression of the CAP. A concentration as low as 0.01 microM DFP produced a 5% depression (P < 0.05) and the maximal depression (30% of control) was observed with 1 microM. The SPK-3 (up to 10 microM) had no effect on the CAP; SPK-3 (10 microM) antagonized the DFP-induced depression of the CAP partially but not after 1 microM DFP. However, the inhibitory concentration of DFP to produce 50% of the maximal depression (IC50) was 0.38 +/- 0.025 microM in the presence of SPK-3 (10 microM; n = 4), against 0.15 +/- 0.05 microM for DFP alone (n = 7). These IC50 values were significantly different (P < 0.05, Student's t-test). The DFP decreased nerve ChE activity by 41% in the absence of SPK-3 and by 31% in the presence of SPK-3. Although SPK-3 could not completely reactivate the inhibited enzyme, it seems reasonable to conclude that the DFP-induced depression of the action potential of sciatic nerve was mediated by inhibiting the ChE activity.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Inibidores da Colinesterase/toxicidade , Isoflurofato/toxicidade , Nervo Isquiático/efeitos dos fármacos , Animais , Regulação para Baixo , Técnicas In Vitro , Compostos de Piridínio/farmacologia , Ranidae
19.
Biophys J ; 71(4): 1776-88, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8889154

RESUMO

13C- and 2H-NMR experiments were used to examine the phase behavior and dynamic structures of N-palmitoylgalactosylsphingosine (NPGS) (cerebroside) and cholesterol (CHOL) in binary mixtures. 13C spectra of 13C=O-labeled and 2H spectra of [7,7-2H2] chain-labeled NPGS as well as 3 alpha-2H1 CHOL indicate that cerebroside and CHOL are immiscible in binary mixtures at temperatures less than 40 degrees C. In contrast, at 40 degrees C < t < or = T(C) (NPGS), up to 50 mol% CHOL can be incorporated into melted cerebroside bilayers. In addition, 13C and 2H spectra of melted NPGS/CHOL bilayers show a temperature and cholesterol concentration dependence. An analysis of spectra obtained from the melted 13C=O NPGS bilayer phase suggests that the planar NH-C=O group assumes an orientation tilted 40 degrees-55 degrees down from the bilayer interface. The similarity between the orientation of the amide group relative to the bilayer interface in melted bilayers and in the crystal structure of cerebroside suggests that the overall crystallographic conformation of cerebroside is preserved to a large degree in hydrated bilayers. Variation of temperature from 73 degrees to 86 degrees C and CHOL concentration from 0 to 51 mol% results in small changes in this general orientation of the amide group. 2H spectra of chain-labeled NPGS and labeled CHOL in NPGS/CHOL bilayer demonstrate that molecular exchange between the gel and liquid-gel (LG) phases is slow on the 2H time scale, and this facilitates the simulation of the two component 2H spectra of [7,7-2H2]NPGS/CHOL mixtures. Simulation parameters are used to quantitate the fractions of gel and LG cerebroside. The quadrupole splitting of [7,7-2H2]NPGS/CHOL mixtures and 2H simulations allows the LG phase bilayer fraction to be characterized as an equimolar mixture of cerebroside and CHOL.


Assuntos
Cerebrosídeos/química , Colesterol/química , Galactosilceramidas/química , Bicamadas Lipídicas/química , Isótopos de Carbono , Deutério , Espectroscopia de Ressonância Magnética/métodos , Conformação Molecular , Ácido Palmítico/química , Termodinâmica
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