Search PubMed⌕ Search

Biomedical subjects

S Sinha

Publications and source records attributed to S Sinha.

At least 55 records · Page 3Linked to original sources
PubMed2005

Synthesis and antitubercular activities of bis-glycosylated diamino alcohols.

Conjugate addition of diamines to glycosyl olefinic esters 1a and 1b followed by reduction of resulting bis-glycosyl beta-amino esters (2-7 and 14-19) with lithium aluminium hydride led to the respective glycosyl amino alcohols (8-13 and 20-25) in moderate to good yields. All the compounds were evaluated for antitubercular activity against Mycobacterium tuberculosis H(37)Ra and H(37)Rv. Few of the compounds exhibited antitubercular activity with MIC as low as 6.25-3.12microg/mL in virulent and avirulent strains. Compound 13 was found to be active against MDR strain and showed mild protection in mice.

Amino Alcohols↗
PubMed2005

A small library of trisubstituted pyrimidines as antimalarial and antitubercular agents.

A small library of 20 trisubstituted pyrimidines were synthesized and evaluated for their in vitro antimalarial and antitubercular activities. Out of the total screened compounds, 16 compounds have shown in vitro antimalarial activity against Plasmodium falciparum in the range of 0.25-2microg/mL and 8 compounds have shown antitubercular activity against Mycobacterium tuberculosis H(37)Ra, at a concentration of 12.5microg/mL.

Animals↗
PubMed2005

Ground state proton radioactivity from 121Pr: when was this exotic nuclear decay mode first discovered?

Ground-state proton radioactivity has been identified from 121Pr. A transition with a proton energy of E(p)=882(10) keV [Q(p)=900(10) keV] and half-life t(1/2)=10(+6)(-3) ms has been observed and is assigned to the decay of a highly prolate deformed 3/2(+) or 3/2(-) Nilsson state. The present result is found to be incompatible with a previously reported observation of ground-state proton radioactivity from 121Pr, which would have represented the discovery of this phenomenon.

Journal Article↗
PubMed2005

Prognostic factors in patients presenting with severe neurological forms of Wilson's disease.

BACKGROUND: Wilson's disease (WD), a metabolic disorder, is believed to be potentially reversible, even in its severe form. However, some patients do not respond to treatment. AIM: To analyse prognostic factors in severe WD. DESIGN: Retrospective audit. METHODS: A total of 140 patients were regularly followed from February 2002 to May 2004. Twenty-nine (18 males, 11 females) had severe disease, as defined by Modified Schwab and England Activities of Daily Living score (MSEADL) of < or=50% or Chu stage of 3. We analysed their clinical, laboratory and MRI features with respect to prognosis. RESULTS: For the severe form, mean age at symptom onset was 11.5 +/- 6.4 years, and at diagnosis, 13.3 +/- 7.0 years. Mean Neurological Symptom Score (NSS), Chu stage, and MSEADL were 26.5 +/- 8.2, 2.7 +/- 0.5 and 24.8 +/- 17.4, respectively. Twenty-one patients underwent MRI; 14 had repeat MRI. Following treatment, 14 (group A) had progressive worsening, including death in two, while 15 (group B) had sustained clinical improvement. Baseline demographic, clinical and laboratory features and MRI scores did not significantly differ between the two groups. However, diffuse white-matter abnormalities were more extensive in group A. Full-dose initial penicillamine therapy could have contributed to worsening in four patients. Drug compliance was poor in both groups but resumption of treatment did not benefit patients in group A. Serial MRI showed regression of lesions only among patients with clinical improvement. DISCUSSION: Severe WD remains a therapeutic challenge, with early diagnosis and treatment are essential. Specific MRI observations, a 'start low-go slow' regimen for penicillamine, and compliance may have prognostic significance. In absence of clinical predictors, genetic attributes need to be explored.

Adolescent↗
PubMed2005

Two-dimensional Bose-Einstein condensate under extreme rotation.

We show that a Bose-condensed gas, under extreme rotation in a 2D anisotropic trap, forms a novel elongated quantum fluid which has a roton-maxon excitation spectrum. For a sufficiently large interaction strength, the roton energy reaches zero and the system undergoes a second order quantum transition to the state with a periodic structure-rows of vortices. The number of rows increases with the interaction, and the vortices eventually form a triangular Abrikosov lattice.

Journal Article↗
PubMed2005

Deviations from liquidlike behavior in molten polymer films at interfaces.

We have performed x-ray specular and diffuse scattering on liquid polymer films and analyzed the spectra as a function of film thickness and molecular weight. The results show that films whose molecular weight is close to the entanglement length behave as simple liquids except that the shortest wavelength is determined by the radius of gyration (R(g)) rather than the monomer-monomer distance. When the molecular weight is higher than the entanglement length, the strong deviations from liquidlike behavior are observed. We find that the long wavelength cutoff vector, q(l,c), scales with film thickness, d as d(-1.1+/-0.1) rather than the usual d(-2) expected for simple liquids. If we assume that these deviations are due to surface pinning of the polymer chains, then our results are consistent with the formalism developed by Fredrickson et al. to explain the capillary wave spectrum that can propagate in a polymer brush.

Journal Article↗
PubMed2005

Role of topical antibiotics in hip surgery. A prospective randomised study.

BACKGROUND: The effectiveness of topical antibiotics has been shown well enough in vitro to justify strong consideration of their use in orthopaedic procedures. We carried out a randomised prospective trial to study the role of topical chloramphenicol ointment application on postoperative wounds following surgeries for hip fractures. METHODS: One hundred cases with fracture neck of femur were enrolled in the study. They were randomized into two treatment groups: one group had chloramphenicol ointment applied at the surgical site at the end of procedure and 3rd day postoperatively, while the control group did not. The wound was checked on the 3rd, 6th, 12th and 30th days postoperatively, by a tissue viability nurse on the guidelines issued by the Scottish Centre for Infection and Environmental Health (SCIEH). RESULTS: We had 12 cases with superficial infection of which 8 belonged to control group. The risk of developing wound infection, however, was not significant with and without the use of chloramphenicol ointment (relative risk 0.430, 95% confidence interval (CI) 0.120-1.544). Using multivariate analysis, no association was found between wound infection and age, gender, type of fracture or type of surgical procedure. Smoking was found to be the only factor significantly associated with infection, with the relative risk for current smokers compared with former/non-smokers being 7.29 (95% CI 1.62-32.67). CONCLUSION: Awareness is needed amongst the general public about the ill effects of smoking. There was reduction in the incidence of wound infection with the use of topical antibiotic ointment. However, this was not statistically significant to recommend its use in routine practice. A larger study should provide useful information on the role of topical antibiotic and its effect on postoperative wound infection.

Administration, Topical↗
PubMed2005

Stellar (n,gamma) cross section of 62Ni.

The 62Ni(n,gamma)63Ni(t(1/2)=100+/-2 yr) reaction plays an important role in the control of the flow path of the slow neutron-capture (s) nucleosynthesis process. We have measured for the first time the total cross section of this reaction for a quasi-Maxwellian (kT=25 keV) neutron flux. The measurement was performed by fast-neutron activation, combined with accelerator mass spectrometry to detect directly the 63Ni product nuclei. The experimental value of 28.4+/-2.8 mb, fairly consistent with a recent calculation, affects the calculated net yield of 62Ni itself and the whole distribution of nuclei with 62<A<90 produced by the weak s process in massive stars.

Journal Article↗
PubMed2005

Neutron spectroscopic factors in 9Li from 2H(8Li,p)9Li.

We have studied the 2H(8Li,p)9Li reaction to obtain information on the spins, parities, and single-neutron spectroscopic factors for states in 9Li, using a radioactive 8Li beam. The deduced properties of the lowest three states are compared to the predictions of a number of calculations for the structure of 9Li. The results of ab initio quantum Monte Carlo calculations are in good agreement with the observed properties.

Journal Article↗
PubMed2005

Level structure of 22Mg: implications for the 21Na(p,gamma)22Mg astrophysical reaction rate and for the 22Mg Mass.

The level structure of (22)Mg has been studied with high-sensitivity gamma-ray spectroscopy techniques. A complete level scheme is derived incorporating all subthreshold states and all levels in the energy region relevant for novae burning. The excitation energy of the most important astrophysical resonance is measured with improved accuracy and found to differ from previous values. Combining the present result with a recent resonance energy measurement of this state leads to a derived (22)Mg mass excess of -400.5(13) keV.

Journal Article↗
PubMed2005

Fly-ash-induced oxidative stress and tolerance in Prosopis juliflora L. grown on different amended substrates.

Field experiments were conducted to study the impact of metal accumulation on malondialdehyde (MDA), cysteine and non-protein thiol (NPSH) contents in the plants of Prosopis juliflora grown on the fly ash (FA) amended with soil, blue green algae (BGA) biofertilizer, farm yard manure, press mud and Rhizobium inoculation. The analysis of data revealed that the level of MDA, cysteine and NPSH was higher in the roots of the plant than leaves, which was found positively correlated with metal accumulation. An increase of 361.14, 64.25 and 305.62% in MDA, cysteine and NPSH contents, respectively was observed after 45 days in the roots of the plants grown in 100% FA as compared to 100% garden soil (GS). The level of MDA, cysteine and NPSH was found less in the plants grown on various amendments of FA showing ameliorating effect on the toxicity induced due to the accumulation of metals. The decrease in MDA, cysteine and NPSH contents was higher in Rhizobium-inoculated plants as compared to uninoculated plants grown on 100% FA. The results showed a high tolerance potential of the plant, which is further increased by inoculating the plant with FA-tolerant Rhizobium showing feasibility of using P. julifilora in environmental monitoring of FA landfills.

Carbon↗
PubMed2005

Synthesis and antimycobacterial activities of glycosylated amino alcohols and amines.

Reduction of glycosyl beta-amino esters (6-14 and 25-30) with lithium aluminum hydride resulted in glycosyl amino alcohols (15-23 and 31-36) in good yields. However, reductive amination of glycosyl aldehydes (1-3) with different amines in presence of sodium borohydride resulted in good to moderate yields of glycosyl amines (37-41). All the compounds were evaluated for antitubercular activity against Mycobacterium tuberculosis H37Ra and H37Rv. Compounds 18, 21, 35 and 36 exhibited antitubercular activities with MIC ranging from 6.25 to 3.12 microg ml(-1).

Amines↗
PubMed2005

Balloon flexor sheathplasty: one-stage grafting at 19 years.

The technique of dilatation of a flexor sheath to allow one-stage grafting was recently described and named balloon flexor sheathplasty [J. Hand Surg. 27B (2001) 487-488]. The scope of this procedure is not yet known and the application after significant delay has not been described. We report a case where balloon flexor sheathplasty allowed return of useful function after an interval of 19 years.

Adult↗
PubMed2005

Evaluation of systems of grading of neurological deficit in tuberculosis of spine.

STUDY DESIGN: Prospective comparative study. OBJECTIVE: To compare the efficacy of the ASIA scoring system and Tuli's classification for assessment of neurological status in a typical case of Pott's paraplegia/tetraplegia and suggest a suitable classification. SETTING: Department of Orthopaedics of University College of Medical Sciences and GTB Hospital, Delhi, India. METHODS: A total of 33 cases of tuberculosis of the spine with paraplegia were evaluated serially for the severity of the neurological deficit by grading systems as suggested by Tuli and ASIA score, during the course of treatment. A total of 111 readings of neurological status were recorded and analysed. RESULTS: Tuli's grading was found to be sensitive for detection of early stage (grade I) of neurological deficit. The rest of the grades (grade II, III, IV) of Tuli's classification have a wide range of sensory-motor deficit and hence are insensitive to early detection of any deterioration/improvement in the neurological status. The ASIA score failed to grade all types of neurological deficit associated with the Pott's spine. The sensory-motor score obtained by the ASIA scale depends on the level of involvement of the spinal cord. The higher the level of the cord damage, the poorer is the score. CONCLUSION: Neither Tuli's grading nor the ASIA scale alone can effectively grade all stages of neurological deficit in tuberculosis of the spine. The neurological deficit in tuberculosis of the spine should be described in stages and each stage should have sensory and motor scoring. A new staging system of Pott's tetraplegia/paraplegia is suggested.

Adolescent↗
PubMed2005

Endoscopic third ventriculostomy in post-tubercular meningitic hydrocephalus: a preliminary report.

Hydrocephalus is a common sequel of tubercular meningitis. Endoscopic third ventriculostomy (ETV) was performed in thirty-five patients. According to the duration of illness, six patients were in the early (less than 6 weeks), nineteen were in the intermediate (6 weeks to 6 months) and ten patients were in the late phase (more than 6 months) of tubercular meningitis (TBM). Six patients were in stage I, seven patients in stage II and twenty-two patients were in stage III. The overall success rate of ETV in TBM was 77 %. Sixty percent had early and seventeen percent had delayed recovery. Obstructive hydrocephalus was present in 54.3 % and 45.7 % had communicating hydrocephalus. The radiological recovery rate was 55.6 %. The outcome with a thin to transparent floor of the third ventricle was 87 %.

Adolescent↗