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Biomedical subjects

A Gupta

Publications and source records attributed to A Gupta.

At least 127 records · Page 7Linked to original sources

Evidence from d+Au measurements for final-state suppression of high-p(T) hadrons in Au+Au collisions at RHIC.

We report measurements of single-particle inclusive spectra and two-particle azimuthal distributions of charged hadrons at high transverse momentum (high p(T)) in minimum bias and central d+Au collisions at sqrt[s(NN)]=200 GeV. The inclusive yield is enhanced in d+Au collisions relative to binary-scaled p+p collisions, while the two-particle azimuthal distributions are very similar to those observed in p+p collisions. These results demonstrate that the strong suppression of the inclusive yield and back-to-back correlations at high p(T) previously observed in central Au+Au collisions are due to final-state interactions with the dense medium generated in such collisions.

Journal Article↗

Non-ligation of the hernial sac during herniotomy: a prospective study.

Herniotomy is performed for the surgical repair of hernia and along with orchiopexy for the closure of associated patent processus vaginalis. Ligation of the hernial sac has been considered mandatory for a successful repair. The present report was designed to study the results of non-ligation of the hernial sac before excision at the neck. It was found that non-ligation has no untoward effect on early complications and recurrence rate on long-term follow-up. It is suggested that it is not necessary to ligate the hernial sac during herniotomy in children.

Child↗

Elevated protein kinase C alpha expression may be predictive of tamoxifen treatment failure.

We previously reported that stable transfection of protein kinase C alpha (PKCalpha) into T47D human breast cancer cells results in tamoxifen (TAM)-resistant tumour growth. Relevance of PKCalpha expression in clinical specimens was determined by comparing PKCalpha expression in tumours from patients exhibiting disease recurrence with patients remaining disease-free following TAM treatment. Our results suggest that PKCalpha expression may predict TAM treatment failure.

Adult↗

Immobilization of xylan-degrading enzymes from Melanocarpus albomyces IIS 68 on the smart polymer Eudragit L-100.

Xylanase of Melanocarpus albomyces IIS 68 was immobilized on Eudragit L-100. The latter is a copolymer of methacrylic acid and methyl methacrylate and is a pH-sensitive smart polymer. The immobilization was carried out by gentle adsorption and an immobilization efficiency of 0.82 was obtained. The enzyme did not leach off the polymer even in the presence of 1 M NaCl and 50% ethylene glycol. The K(m) of the enzyme changed from 5.9 mg ml(-1) to 9.1 mg ml(-1) upon immobilization. The V(max) of the immobilized enzyme showed an increase from 90.9 micro mol ml(-1) min(-1) (for the free enzyme) to 111.1 micro mol ml(-1) min(-1). The immobilized enzyme could be reused up to ten times without impairment of the xylanolytic activity. The immobilized enzyme was also evaluated for its application in pre-bleaching of eucalyptus kraft pulp.

Enzymes, Immobilized↗

Phase I study of thalidomide for the treatment of plexiform neurofibroma in neurofibromatosis 1.

An open-label phase I trial of thalidomide (TL) in 20 patients with neurofibromatosis 1 (NF1) treated symptomatic plexiform neurofibroma (PNF). TL was well tolerated in doses up to 200 mg/d. Adverse reactions included transient somnolence in four, evanescent rash in two, and reversible mild peripheral neuropathy in two patients. Four patients showed less than 25% reduction in the tumor size. TL may have a role in the treatment of PNF and should be explored in a larger controlled study, possibly using higher doses of TL.

Adolescent↗

Intravenous immunoglobulin for the treatment of Kawasaki disease in children.

BACKGROUND: Kawasaki disease is the most common cause of acquired heart disease in children in developed countries. The coronary arteries supplying the heart can be damaged in Kawasaki disease. The principal advantage of timely diagnosis is the potential to prevent this complication with early treatment. Intravenous immunoglobulin (IVIG) is widely used for this purpose. OBJECTIVES: The objective of this review was to evaluate the effectiveness of IVIG in treating, and preventing cardiac consequences, of Kawasaki disease in children. SEARCH STRATEGY: Electronic searches of the Cochrane Peripheral Vascular Disease Group Specialised Register, CENTRAL, MEDLINE, EMBASE, and CINAHL were performed (last searched April 2003). We also searched references from relevant articles and contacted authors where necessary. In addition we contacted experts in the field for unpublished works. SELECTION CRITERIA: Randomised controlled trials of intravenous immunoglobulin to treat Kawasaki disease were eligible for inclusion. DATA COLLECTION AND ANALYSIS: Fifty-nine trials were identified in the initial search. On careful inspection only sixteen of these met all the inclusion criteria. Trials were data extracted and assessed for quality by at least two reviewers. Data were combined for meta-analysis using relative risk ratios for dichotomous data or weighted mean difference for continuous data. A random effects statistical model was used. MAIN RESULTS: The meta-analysis of IVIG versus placebo, including all children, showed a significant decrease in new coronary artery abnormalities (CAAs) in favour of IVIG, at thirty days RR (95% CI) = 0.74 (0.61 to 0.90). No statistically significant difference was found thereafter. A subgroup analysis excluding children with CAAs at enrollment also found a significant reduction of new CAAs in children receiving IVIG RR (95%) = 0.67 (0.46 to 1.00). There was a trend towards benefit from IVIG at sixty days (p=0.06). Results of dose comparisons showed a decrease in the number of new CAAs with increased dose. The meta-analysis of 400 mg/kg/day for five days versus 2 gm/kg in a single dose showed statistically significant reduction in CAAs at thirty days RR (95%) = 4.47 (1.55 to 12.86). This comparison also showed a significant reduction in duration of fever with the higher dose. There was no statistically significant difference noted between different preparations of IVIG. There was no statistically significant difference of adverse effects in any group. REVIEWER'S CONCLUSIONS: Children fulfilling the diagnostic criteria for Kawasaki disease should be treated with IVIG (2 gm/kg single dose) within 10 days of onset of symptoms.

Child↗

Neuro-endoscopic surgery--experience and outcome analysis of 102 consecutive procedures in a busy neurosurgical centre of India.

BACKGROUND: Neuro-endoscopic surgery is finding increasing application for various clinical conditions. We present our experience of 100 cases of diverse intracranial lesions, including infections, managed by neuro-endoscopy in a busy neurosurgical department in the developing world. MATERIAL AND METHODS: One hundred patients treated from March 1996 to February 2002 formed the study group. Management of hydrocephalous by Endoscopic third ventriculostomy (ETV) was the aim in 75 patients with or without diagnostic biopsy. Excision or resection was attempted in 25 patients with juxtaventricular or intraventricular lesions. Endoscopic procedures included total tumour resection, partial resection, biopsy, stent placement, Monroplasty, septostomy and third ventriculostomy. Outcomes of endoscopic surgery were evaluated with respect to clinical and/or radiological improvement, complications and need for additional therapy. FINDINGS: Endoscopy was the only surgical treatment in 59 patients. Intermittent lumbar drainage for cerebrospinal fluid leak, shunt, microsurgery and/or repeat endoscopic surgery were additional treatments needed in 39 patients, who subsequently had increased hospital stay, postoperative morbidity and a higher cost of treatment. Peroperative bleeding due to distorted anatomy and obscured vision in 2 patients with post-infective loculated hydrocephalus (LH) resulted in two fatalities (2%) in the early post-operative period. INTERPRETATION: Neuro-endoscopic surgery cuts down operative time and hospital stay, reduces cost and results in a faster turnover of the patients. It is a versatile and useful tool for a busy neurosurgical department.

Adolescent↗

Spermicidal efficacy of H2-receptor antagonists and potentiation with 2', 4'-dichlorobenzamil hydrochloride: role of intrasperm Ca2+.

The present investigation was designed to study the possible role of intrasperm Ca(2+) in spermicidal action of H(2)-receptor antagonists. Influence of commonly used H(2)-receptor antagonists cimetidine, ranitidine and famotidine on sperm viability and intrasperm Ca(2+) was evaluated in ejaculated human semen samples. All these drugs were found to reduce sperm viability in a dose- and time-dependent manner. This action was accompanied with elevation of intrasperm Ca(2+). 2', 4'-dichlorobenzamil hydrochloride (DBZ), a Na(+)-Ca(2+) exchange inhibitor, that is known to elevate intrasperm Ca(2+), potentiated the spermicidal action of H(2)-receptor antagonists. Intrasperm Ca(2+) was found to rise at much faster rate when DBZ was combined with any of the three H(2)-receptor antagonists. Due to this, the maximum Ca(2+) level required to produce death of sperm cells was attained much earlier as compared to the per se effect of any one of these drugs. These results suggest that elevation of intrasperm Ca(2+) by H(2)-receptor antagonists plays a key role in influencing sperm viability.

Adult↗

Simulating thermal power plant processes on a message passing environment.

Simulators play a very important role in the operation of thermal power plants and also in the design of control systems for these plants. To cater to this requirement elaborate methodologies have been developed to simulate thermal power plant processes in an interactive way. Due to the intensive computations involved, such simulators use one or more high through-put computers known as the simulation computers. This paper puts forward a method where parallel processing on a low latency message passing environment has been used to simulate thermal power plant processes following a modular approach. This eliminates the need of an expensive high through-put simulation computer, thus cutting down the hardware cost associated with a simulator and increasing the system reliability manifold.

Journal Article↗

Species, strain and developmental variations in hippocampal neuronal and endothelial nitric oxide synthase clarify discrepancies in nitric oxide-dependent synaptic plasticity.

Nitric oxide (NO) has been implicated in long-term potentiation (LTP) in pyramidal neurons in cellular area 1 (CA1) of the hippocampus. However, considerable confusion exists about the exact role of NO, and the contribution of the endothelial nitric oxide synthase (eNOS) and neuronal nitric oxide synthase (nNOS) isoforms of NO synthase to NO-dependent LTP (NO-LTP), with results often varying, depending on the organism and experimental paradigm used. Using immunohistochemistry and in situ hybridization, we contrast NO synthase expression and activity in rat, mouse, and human hippocampus. nNOS is prominently expressed in all CA1 pyramidal cells of C57B6 mice and humans, while in rats and SV129 mice, its levels are much lower and restricted to the caudal hippocampus. By contrast, eNOS is restricted to endothelial cells. We observe N-methyl-D-aspartate-dependent citrulline production in pyramidal cells of mouse hippocampus, which is absent in nNOS(Delta/Delta) animals. Finally, we observe robust nNOS expression in human CA1 pyramidal cells.The considerable axial, developmental, strain and species-dependent variations in nNOS expression in CA1 pyramidal neurons can explain much of the variation observed in reports of NO-dependent LTP. Moreover, our data suggest that NO produced by eNOS in endothelial cells may play a paracrine role in modulating LTP.

Animals↗

Patient-controlled regional analgesia (PCRA) with ropivacaine after arthroscopic subacromial decompression.

BACKGROUND: The aim of the study was to evaluate postoperative analgesia and safety of wound instillation of ropivacaine either by a single dose or a patient-controlled regional anaesthesia (PCRA) technique. METHODS: In 40 patients undergoing arthroscopic subacromial decompression the surgeon placed a catheter into the subacromial space at the end of the operation. In Phase I (10 patients), ropivacaine 250 mg was injected twice within 1 h. In Phase II, 30 patients were randomised into three groups: group prilocaine-ropivacaine (PR) = 20 ml of 1% prilocaine-epinephrine injected preoperatively into the subacromial bursa + 20 ml of 0.5% ropivacaine infused in the catheter postoperatively; group saline-ropivacaine (SR) = saline-epinephrine (20 ml) preoperatively + 0.5% ropivacaine as in group PR; group saline-saline (SS) = saline-epinephrine (20 ml) preoperatively + saline postoperatively. The PCRA pump was filled with local anaesthetic or saline to allow boluses of 10-ml each, maximum one bolus/h, via the catheter. Pain relief, side-effects and venous plasma concentration of ropivacaine were evaluated during a 24-h-test period. RESULTS: The free plasma concentration of ropivacaine was 0.12 + 0.041 mg l-1 in Phase I. No adverse effects were seen. In Phase II pain at rest and on movement was lower in group PR than in group SS during the first 30 min postoperatively (P < 0.05). Group PR had the lowest morphine consumption (P < 0.05). Five to seven boluses were administered via the PCRA-pump, and 20 min after administration of the study solution, pain was lower in groups PR and SR compared with group SS (P < 0.001). CONCLUSIONS: Preoperative intrabursal prilocaine with epinephrine + postoperative subacromial administration of ropivacaine by PCRA-technique provided the most effective analgesia with no major side-effects. The free plasma concentrations of ropivacaine were far below toxic concentrations.

Adult↗

Dexamethasone is as effective as ondansetron for the prevention of postoperative nausea and vomiting following breast surgery.

INTRODUCTION: Postoperative nausea and vomiting remain a common problem following breast surgery. This study assesses whether dexamethasone is as effective as ondansetron in the control of postoperative nausea and vomiting (PONV). METHODS: Eighty ASA I-III patients undergoing breast surgery for carcinoma of the breast were included in the study. Following premedication with diazepam 5-10 mg, patients were induced with fentanyl 50 micro g and propofol 2-2.5 mg kg-1. A larynx mask was inserted and anesthesia maintained with sevoflurane in oxygen and nitrous oxide. Patients were then randomly divided into two groups: Group D (dexamethasone) was given 4 mg dexamethasone i.v. after induction and Group O (ondansetron) was given 4 mg ondansetron at the same time point. Postoperatively, nausea, vomiting and pain were recorded at 1-h intervals during 4 h, and thereafter every 4 h during 24 h. RESULTS: The incidence of PONV during 24 h was 37% and 33% in Group D and Group O, respectively (NS). No differences were found between the groups in the incidence of postoperative nausea, vomiting or pain at the different time intervals. No differences were found in the incidence of PONV in smokers vs. non-smokers. No side-effects of these drugs were observed. CONCLUSIONS: Ondansetron 4 mg or dexamethasone 4 mg are equally effective in the prevention of postoperative nausea and vomiting following breast surgery. Other factors being similar, the difference in cost between these drugs would favor the use of dexamethasone instead of ondansetron when monotherapy against PONV is used.

Adolescent↗

Low-dose bupivacaine plus fentanyl for spinal anesthesia during ambulatory inguinal herniorrhaphy: a comparison between 6 mg and 7. 5 mg of bupivacaine.

BACKGROUND: Inguinal herniorrhaphy is commonly performed as an outpatient procedure. Spinal anesthesia offers some advantages over general anesthesia in this setting. METHODS: Forty patients were randomly divided into two groups according to a double-blind protocol: Group L had spinal anesthesia with bupivacaine 6.0 mg and Group H with bupivacaine 7.5 mg; in both groups, fentanyl 25 micro g was added to the spinal anesthetic. The sensory block was measured by 'pin-prick' and the motor block was evaluated by a modified Bromage scale. RESULTS: No differences were seen in the spread, duration and regression of sensory block between the groups on the operated side. A greater number of patients required analgesics during the operation in Group L (6) compared with Group H (1) (P<0.05). The return of the modified Bromage scale to grade 0 was earlier in Group L than in Group H (P<0.05) but the time to mobilization and discharge was similar. Seven patients (17%) needed to be catheterized and two had the catheter retained overnight. Times to home discharge (median) were 350 and 445 min, respectively, in Groups L and H. Postoperatively and during the first week, visual analog pain scores, analgesic requirements and side-effects were similar between the groups. In Group H, 95% of the patients and in Group L 85% would have the same anesthetic again if operated upon for a similar procedure. CONCLUSIONS: Spinal anesthesia with bupivacaine 7.5 mg and fentanyl offers an alternative to general or local anesthesia for ambulatory inguinal herniorrhaphy. However, the long discharge times and risk for urinary retention restrict its routine use in all patients.

Adult↗

Increased spontaneous, tumor necrosis factor receptor- and CD95 (Fas)-mediated apoptosis in cord blood T-cell subsets from Turner's syndrome.

Increased spontaneous as well as TNF-alpha-induced and CD95-mediated apoptosis were observed in CD4+ and CD8+ T cells from the cord blood of a patient with Turner's syndrome as compared to normal cord blood. Increased apoptosis was associated with an increased expression of TNFR-1, TNFR-2, and CD95L and decreased expression of cIAP1 and FLIP(L). No significant difference was observed in the expression of Bcl-2 family members (Bcl-2, Bax) between Turner's syndrome cord blood and normal cord blood lymphocytes. This study demonstrates that increased apoptosis of T-cell subsets in Turner's syndrome occurs via the death receptor pathway and may play a role in the pathogenesis of immunological defects associated with Turner's syndrome.

Apoptosis↗

AMP-activated protein kinase, super metabolic regulator.

The AMP-activated protein kinase (AMPK) is a metabolic-stress-sensing protein kinase that regulates metabolism in response to energy demand and supply by directly phosphorylating rate-limiting enzymes in metabolic pathways as well as controlling gene expression.

AMP-Activated Protein Kinases↗