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P Gupta

Publications and source records attributed to P Gupta.

At least 37 records · Page 2Linked to original sources
PubMed2004

Using absorption imaging to study ion dynamics in an ultracold neutral plasma.

We report optical absorption imaging of ultracold neutral strontium plasmas. The ion absorption spectrum determined from the images is Doppler broadened and thus provides a quantitative measure of the ion kinetic energy. For the particular plasma conditions studied, ions heat rapidly as they equilibrate during the first 250 ns after plasma formation. Equilibration leaves ions on the border between the weakly coupled gaseous and strongly coupled liquid states. On a longer time scale of microseconds, pressure exerted by the trapped electron gas accelerates the ions radially.

Journal Article↗
PubMed2004

Arthrobacter gangotriensis sp. nov. and Arthrobacter kerguelensis sp. nov. from Antarctica.

Two coryneform bacteria were isolated from a penguin rookery soil sample collected in Antarctica, near the Indian station Dakshin Gangotri (strain Lz1y(T)), and from sea water from Kerguelen island, Antarctica (strain KGN15(T)). They have morphological and chemotaxonomic properties (peptidoglycan A4alpha type; major menaquinones MK-8, MK-9 and MK-10; predominant fatty acids anteiso-C(15 : 0) and anteiso-C(17 : 0)) that are characteristic of members of the genus Arthrobacter. The isolates shared 97.8 % 16S rRNA gene sequence similarity to each other and were most closely related to Arthrobacter sulfureus (about 98.5 % sequence similarity). DNA-DNA hybridization experiments revealed 50 % relatedness between the isolates, while the levels of DNA-DNA relatedness between strains Lz1y(T) and KGN15 (T) and their phylogenetic relative, A. sulfureus, were respectively 54 and 12 %. Based on the above data and distinct phenotypic differences between the isolates and A. sulfureus, two novel species are proposed, Arthrobacter gangotriensis sp. nov. (type strain Lz1y(T)=DSM 15796(T)=JCM 12166(T)) and Arthrobacter kerguelensis sp. nov. (type strain KGN15(T)=DSM 15797(T)=JCM 12165(T)).

Antarctic Regions↗
PubMed2004

Bilateral adductor vocal cord paresis following endotracheal intubation for general anaesthesia.

Recurrent laryngeal nerve palsy is a rare complication of endotracheal intubation. We report a case of bilateral vocal cord palsy following endotracheal intubation for general anaesthesia. The clinical picture was of hoarseness and aspiration suggestingpartialparesis, as complete bilateral recurrent laryngeal nerve palsy usually causes acute airway obstruction due to unopposed vocal cord adduction. Compression of the anterior branch of the recurrent laryngeal nerve between the cuff of the endotracheal tube and the posterior part of the thyroid cartilage was the likely mechanism. Ensuring that the cuff of the endotracheal tube is distal to the cricoid cartilage and that the pressure in the cuff is kept to the minimum required to prevent a gas leak should prevent this complication.

Adult↗
PubMed2004

Correlation of mutations detected by INNO-LiPA with levels of rifampicin resistance in Mycobacterium tuberculosis.

BACKGROUND & OBJECTIVES: Due to emergence of drug resistance in Mycobacterium tuberculosis, there is a need to have accurate and rapid methods for detection of drug resistance to important drugs like rifampicin. The present study was aimed at evaluation of a commercially available INNO-LiPA assay, for the detection of mutation in rpoB gene region of M. tuberculosis and correlate these mutations with levels of rifampicin resistance for assessing their clinical relevance. METHODS: Fifty five well-characterized isolates of M. tuberculosis deposited from various regions of India in Mycobacterial Repository Centre at the CJILOMD, Agra were subjected to susceptibility testing for rifampicin at various concentrations of drug viz., 10, 40, 64, 128 microg/ml on Lowenstein- Jensen (LJ) medium. rpoB gene fragment (260 bp) was amplified using Rif-TB amplification kit and after hybridization, detection was done by using INNO-LiPA Rif TB kit. RESULTS: The rpoB gene could be amplified from DNA extracted from all the 55 culture isolates and showed clear hybridization pattern with M. tuberculosis complex specific probes on LiPA strips. Mutations detected were correlated with degree of rifampicin resistance. All the sensitive isolates (identified by MIC) were identified as rifampicin sensitive (100%) by INNO-LiPA as they exhibit positive for wild type 'S' probes and negative for 'R' probes. Two of the 5 isolates, resistant at 10 microg/ml and 40 microg/ml had either D516V, H526Y mutations or unknown mutations. Thirty (85.71%) isolates resistant at clinically relevant levels (64,128microg/ml) exhibited double, triple or more 'R' type mutations (R(2(D516V)), R(4a(H526Y)), R(4b(H526D)), R(5(S531L))) as well as unknown mutations present at 'S' probes region whereas remaining isolates did not show any mutation by this method. This method could identify with definitiveness 60 per cent ( 21/35) isolates as rifampicin resistant as mutations observed in others were also present in isolates with low levels of resistance. INTERPRETATION & CONCLUSION: The results indicate that INNO-LiPA Rif TB test is a rapid and easy to use method for detection of mutations associated with rifampicin resistance in M. tuberculosis. However, as some of these mutations are also present in isolates with low degree of resistance which are still microbiologically sensitive to rifampicin, there is a need to improve this assay by exclusion of some of the current probes and inclusion of more probes.

Antibiotics, Antitubercular↗
PubMed2003

2-(2-Naphthyloxy)acetate derivatives. II. A new class of antiamnesic agents.

The title compounds, 4-(2-naphthyloxymethylcarbonyl)morpholine, C(16)H(17)NO(3), (I), and 4-methyl-1-(2-naphthyloxymethylcarbonyl)piperazine, C(17)H(20)N(2)O(2), (II), are potential antiamnesics. The morpholine ring in (I) and the piperazine ring in (II) adopt chair conformations. In (I), the molecules are linked by weak intermolecular C-H.O interactions into chains that have a graph-set motif of C(10), while in (II), the molecules are linked by weak intermolecular C-H.O interactions that generate two C(7) graph-set motifs. The dihedral angle between the naphthalene moiety and the best plane through the morpholine ring is 20.62 (4) degrees in (I), while the naphthalene moiety is oriented nearly perpendicular to the mean plane of the piperazine ring in (II).

Acetates↗
PubMed2003

Cross-sectional area of the lumbar back muscles as a function of torso flexion.

OBJECTIVE: Quantification of the maximum anatomical cross-sectional area of the lumbar back muscles as a function of torso flexion angle and development of prediction equations as a function of torso flexion and anthropometric measures. BACKGROUND: Cross-sectional areas of the lumbar back muscles used as inputs into biomechanical models have traditionally been derived from subjects lying in the neutral supine posture. However, it is known that the cross-sectional area of muscle is altered as the torso angle changes. DESIGN: Experimental design consisted of a two-factor multivariate analysis of variance on the cross-sectional area of the lumbar torso muscle across the lumbar levels, as a function of gender and torso angle. Hierarchical linear regression was utilized to assess the association between cross-sectional area and individual and torso posture characteristics. METHOD: Axial MRI scans, through and parallel to each of the lumbar intervertebral discs at four torso flexion positions were obtained from subjects in a lateral recumbent posture. Cross-sectional areas were quantified and converted into anatomical cross-sectional areas utilizing known fascicle orientations. RESULTS: The maximum anatomical cross-sectional area was located between the L(3)/L(4) and L(4)/L(5) level in the neutral posture. The anatomical cross-sectional areas at the L(4)/L(5) and L(5)/S(1) decreased during torso flexion, however, the percent change varied as a function of the individual level. The majority of the anatomical cross-sectional area variability was explained by gender and body mass. Lumbar curvature explained a larger proportion of the anatomical cross-sectional area variability at the lower lumbar levels than at the higher lumbar levels. CONCLUSIONS: The maximum anatomical cross-sectional area of the lumbar back muscles occur at the neutral torso posture and did not decrease as a function of torso flexion. When using maximum anatomical cross-sectional area or specific lumbar level anatomical cross-sectional areas, it appears necessary to account for gender and body mass. At the lower lumbar levels, knowledge of spinal curvature plays an increasing role in the estimation of the size of the lumbar torso muscle cross-sectional area. RELEVANCE: This research indicates the lower lumbar level trunk muscle anatomical cross-sectional area decrease as torso flexion increases, however, the maximum lumbar trunk muscle anatomical cross-sectional area does not vary as a function of torso flexion. Accounting for gender, body mass, torso characteristics and lumbar curvature may help increase accuracy of anatomical cross-sectional area prediction, as well as muscle force predictions from biomechanical models.

Adult↗
PubMed2003

Awareness of brain death and organ transplantation among select Indian population.

BACKGROUND: With the improvement in transplant technology major organ transplantation is gradually becoming the treatment of choice in many conditions. The present study assesses the awareness of the concepts of brain death and organ transplantation among public. METHODS: Six hundred thirty six select populations, which included office-goers of Delhi, class 12th school children of a reputed public school and villagers, were interviewed to assess their knowledge in various aspects of brain death and organ transplantation. RESULTS: There was widespread acceptance of organ transplantation among this population. The most alarming feature was that the awareness of the concept of brain death and its importance for organ donation was extremely low. Only small number of individuals were aware that brain death is legal in India. Awareness about brain death was especially low among villagers. CONCLUSIONS: Education about various aspects of brain deaths, its immense importance for organ donation and legality of brain death in India needs to be highlighted.

Adolescent↗
PubMed2002

Carbon fibres and plasma-preserved tendon allografts for gap repair of flexor tendon in bovines: clinical, radiological and angiographical observations.

Twenty-four tenorrhaphies were performed at the mid-metatarsal region in 12 crossbred calves under xylazine-ketamine spinal analgesia. A 2.5-cm long gap was created in the superficial digital flexor (SDF) tendon and immediately repaired with carbon fibres in the animals of group I and with plasma-preserved tendon allografts in group II. Clinical examination revealed a slight increase (P > 0.05) in rectal temperature, heart and respiratory rate for 2-4 days postoperation in both groups. Milder pain and exudation as well as earlier restoration of tendon gliding movements and weight bearing were observed in group I as compared to group II. Air-tendogram in the carbon fibre group on day 30 revealed restoration of continuity across the defect of the tendon. whereas, in the allograft group, a dense homogeneous swelling was seen along the flexors. Regression of peritendinous adhesions and swelling at the reconstructed site at later stages was seen in both groups. Angiography showed hypervascularization at the reconstructed site on day 14 in the carbon fibre group, however, in the allograft group the site appeared to be relatively avascular. On days 30 and 90, blood vessels were normally organized in both groups.

Angiography↗
PubMed2002

Mammary tuberculosis: report on 52 cases.

Fifty two cases of tuberculosis of the breast encountered over a 15 year period and accounting for 3% of all breast lesions are reported. The classic presentation was a breast lump with associated sinus in 39%, isolated breast lump in 23%, sinus without lump in 12%, and tender nodularity in 23% of the patients. Associated axillary lymphadenopathy was found in 41%. Diagnosis was confirmed by fine needle aspiration cytology or histology in all the cases and antitubercular therapy formed the mainstay of treatment.

Adolescent↗
PubMed2002

Pulmonary arteriovenous malformations: effect of embolization on right-to-left shunt, hypoxemia, and exercise tolerance in 66 patients.

OBJECTIVE: This study assessed the effect and safety of percutaneous transcatheter coil embolization of pulmonary arteriovenous malformations. MATERIALS AND METHODS: In 58 (88%) of 66 patients, all malformations with feeding vessels greater than or equal to 3 mm in diameter were embolized with steel coils. Arterial oxygen saturation at rest and exercise, intrapulmonary right-to-left anatomic shunt fraction ((99m)Tc-macroaggregate injection), maximum exercise capacity (incremental work rate test), and pulmonary function were measured before and after embolization. Complications were analyzed. RESULTS: Three categories of patients were identified. Patients in group 1 (27%) had complete occlusion of all angiographically visible pulmonary arteriovenous malformations; patients in group 2 (61%) had complete occlusion of all malformations with feeding vessels greater than or equal to 3 mm in diameter, but with smaller lesions persisting; and patients in group 3 (12%) had incomplete embolization, with feeding vessels greater than or equal to 3 mm in diameter remaining. The mean right-to-left shunt after embolization was least in group 1 (7%), intermediate in group 2 (10%), and greatest in group 3 (19%). Arterial oxygen saturation and right-to-left shunt fraction returned to normal levels (>96% and <3.5%, respectively) in 33% of patients. A significant improvement occurred after embolization in carbon monoxide diffusing capacity per unit of alveolar volume and in exercise capacity in 16 and 10 patients, respectively. In 93 procedures, 12 complications (13%) occurred. CONCLUSION: Coil embolization of pulmonary arteriovenous malformations is effective in reducing right-to-left anatomic shunt fraction and in improving arterial oxygenation. Coil embolization of pulmonary arteriovenous malformations is well tolerated and has a low complication rate.

Adolescent↗
PubMed2002

Study of yoga asanas in assessment of pulmonary function in NIDDM patients.

Certain yoga asanas if practiced regularly are known to have beneficial effects on human body. These yoga practices might be interacting with various, somato-neuro-endocrine mechanisms to have therapeutic effects. The present study done in twenty four NIDDM patients of 30 to 60 year old, provides metabolic and clinical evidence of improvement in glycaemic control and pulmonary functions. These middle-aged subjects were type II diabetics on antihyperglycaemic and dietary regimen. Their baseline fasting and postprandial blood glucose and glycosylated Hb were monitored along with pulmonary function studies. The expert gave these patients training in yoga asanas and were pursed 30-40 min/day for 40 days under guidance. These asanas consisted of 13 well known postures, done in a sequence. After 40 days of yoga asanas regimen, the parameters were repeated. The results indicate that there was significant decrease in fasting blood glucose levels (basal 190.08 +/- 90.8 in mg/dl to 141.5 +/- 79.8 in mg/dl). The postprandial blood glucose levels also decreased (276.54 +/- 101.0 in mg/dl to 201.75 +/- 104.1 in mg/dl), glycosylated hemoglobin showed a decrease (9.03 +/- 1.4% to 7.83 +/- 2.6%). The FEV1, FVC, PEFR, MVV increased significantly (1.81 +/- 0.4 lt to 2.08 +/- 0.4 lt, 2.20 +/- 0.6 lt to 2.37 +/- 0.5 lt, 3.30 +/- 1.0 lt/s to 4.43 +/- 1.4 lt/s and 64.59 +/- 25.7 lt min to 76.28 +/- 28.1 lt/min respectively). FEV1/FVC% improved (85 +/- 0.2% to 89 +/- 0.1%). These findings suggest that better glycaemic control and pulmonary functions can be obtained in NIDDM cases with yoga asanas and pranayama. The exact mechanism as to how these postures and controlled breathing, interact with somato-neuro-endocrine mechanism affecting metabolic and pulmonary functions remains to be worked out.

Adult↗
PubMed2001

Spine loading characteristics of patients with low back pain compared with asymptomatic individuals.

STUDY DESIGN: Patients with low back pain and asymptomatic individuals were evaluated while performing controlled and free-dynamic lifting tasks in a laboratory setting. OBJECTIVE: To evaluate how low back pain influences spine loading during lifting tasks. SUMMARY OF BACKGROUND DATA: An important, yet unresolved, issue associated with low back pain is whether patients with low back pain experience spine loading that differs from that of individuals who are asymptomatic for low back pain. This is important to understand because excessive spine loading is suspected of accelerating disc degeneration in those whose spines are damaged already. METHODS: In this study, 22 patients with low back pain and 22 asymptomatic individuals performed controlled and free-dynamic exertions. Trunk muscle activity, trunk kinematics, and trunk kinetics were used to evaluate three- dimensional spine loading using an electromyography- assisted model in conjunction with a new electromyographic calibration procedure. RESULTS: Patients with low back pain experienced 26% greater spine compression and 75% greater lateral shear (normalized to moment) than the asymptomatic group during the controlled exertions. The increased spine loading resulted from muscle coactivation. When permitted to move freely, the patients with low back pain compensated kinematically in an attempt to minimize external moment exposure. Increased muscle coactivation and greater body mass resulted in significantly increased absolute spine loading for the patients with low back pain, especially when lifting from low vertical heights. CONCLUSIONS: The findings suggest a significant mechanical spine loading cost is associated with low back pain resulting from trunk muscle coactivation. This loading is further exacerbated by the increases in body weight that often accompany low back pain. Patient weight control and proper workplace design can minimize the additional spine loading associated with low back pain.

Adult↗
PubMed2001

Disruption of PPT1 or PPT2 causes neuronal ceroid lipofuscinosis in knockout mice.

PPT1 and PPT2 encode two lysosomal thioesterases that catalyze the hydrolysis of long chain fatty acyl CoAs. In addition to this function, PPT1 (palmitoyl-protein thioesterase 1) hydrolyzes fatty acids from modified cysteine residues in proteins that are undergoing degradation in the lysosome. PPT1 deficiency in humans causes a neurodegenerative disorder, infantile neuronal ceroid lipofuscinosis (also known as infantile Batten disease). In the current work, we engineered disruptions in the PPT1 and PPT2 genes to create "knockout" mice that were deficient in either enzyme. Both lines of mice were viable and fertile. However, both lines developed spasticity (a "clasping" phenotype) at a median age of 21 wk and 29 wk, respectively. Motor abnormalities progressed in the PPT1 knockout mice, leading to death by 10 mo of age. In contrast, the majority of PPT2 mice were alive at 12 mo. Myoclonic jerking and seizures were prominent in the PPT1 mice. Autofluorescent storage material was striking throughout the brains of both strains of mice. Neuronal loss and apoptosis were particularly prominent in PPT1-deficient brains. These studies provide a mouse model for infantile neuronal ceroid lipofuscinosis and further suggest that PPT2 serves a role in the brain that is not carried out by PPT1.

Animals↗
PubMed2001

HIV gp120 V(1)/V(2) and C(2)-V(3) domains glycoprotein compatibility is required for viral replication.

The envelope gene, especially the V(3) region, of HIV-1 has been shown to be a principal determinant of cell tropism, replication and cytopathogenicity of the virus. In addition, the V(1)/V(2) region of the envelope gene has been found to be an important factor in cell tropism. We examined the compatibility between the V(1)/V(2) and C(2)-V(3) domains of HIV-1 gp120 in different combinations on viral replication by using envelope recombinants between ME1 and ME46, two infectious molecular clones with diverse biologic activity longitudinally isolated from one seropositive subject. Our data demonstrate that a proper interaction between the regions of V(1)/V(2)and C(2) is essential for viral infection and hence replication. Sequence analysis and subsequent site directed mutagenesis study indicate that the pattern of potential envelope N-glycosylation in the V(1)/V(2) and C(2)-V(3) regions may be the determining factor in such interaction between these two regions. It is possible that improper N-glycosylation sites while not affecting virus assembly, can influence through steric hindrance the conformational change of the V(3) region that is required for the co-receptor attachment and hence the viral infectivity.

Binding Sites↗