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Biomedical subjects

A Kumar

Publications and source records attributed to A Kumar.

At least 19 recordsLinked to original sources
PubMed2007

Nicotine exposure alters in vivo human responses to endotoxin.

The alpha 7 nicotinic receptor is reportedly a key element in the cholinergic anti-inflammatory pathway. Because a prototypical ligand for this receptor is nicotine, we studied the in vivo human response to bacterial endotoxin or lipopolysaccharide (LPS) in the context of nicotine or placebo pretreatment. Twelve adult male normal subjects were studied prospectively. Six received overnight transcutaneous nicotine administration by application of a standard patch (7 mg). Six hours later, all subjects were given an intravenous dose of endotoxin (2 ng/kg) and were evaluated for an additional 24 h for circulating levels of inflammatory biomarkers, vital signs and symptoms. The nicotine subjects had elevated blood levels of the nicotine metabolite, continine, prior to and throughout the 24-h post-endotoxin exposure phase. Subjects receiving nicotine exhibited a significantly lower temperature response as well as attenuated cardiovascular responses for 2.5-6 h after LPS exposure. In addition, increased circulating interkeukin (IL)-10 and cortisol levels were also noted in nicotine subjects. These data indicate an alteration in LPS-induced systemic inflammatory responses in normal subjects exposed to transcutaneous nicotine. In this model of abbreviated inflammation, nicotine exposure attenuates the febrile response to LPS and promotes a more prominent anti-inflammatory phenotype.

Administration, Cutaneous↗
PubMed2007

Is fluoroscopy essential for retrieval of lower ureteric stones?

INTRODUCTION: The aim of this study was to assess the efficacy of ureteroscopy for lower ureteric stones without the use of fluoroscopy. PATIENTS AND METHODS: Between June 2001 and January 2005, a total of 110 patients with a mean age of 33.5 years (range 12-65) suffering from of lower ureteral calculi (below the upper margin of the sacroiliac joint) prospectively underwent ureteroscopic removal. Retrograde pyelography was avoided, and no safety guidewire was placed. Whenever required, the ureteric meatus was dilated with a ureteric balloon under direct vision. Double-J stent placement was done with the aid of ureteroscopy. A fluoroscope was kept standby. The patients had a postoperative X-ray of the kidney-ureter-bladder region to document the stone clearance. RESULTS: The mean stone size was 8.7 mm (range 6-15). Complete clearance without the use of fluoroscopy was achieved in 99 patients (94.2%). Fluoroscopy was required in 6 patients (4%) for calcified stricture (n = 1), duplex system (n = 1), narrow and tortuous meatus causing difficulty in passing the 5-Fr balloon dilator (n = 3), and confirmation of spontaneous passage of the stone (n = 1). Of the 13 patients who required balloon dilatation it was successfully achieved without fluoroscopy. Double-J stenting was done due to mucosal ulceration (n = 3), polypoid reaction (n = 2), and perforation (n = 1). All these patients had correct placement of the stent, as confirmed by X-ray of the kidney-ureter-bladder region postoperatively. CONCLUSIONS: To uphold the notion for radiation exposure to be as low as reasonably achievable, ureteroscopic stone retrieval can safely be done without the use of fluoroscopy in a significant number of patients.

Adolescent↗
PubMed2006

Postcholecystectomy benign biliary strictures - long-term results.

BACKGROUND: Cholecystectomy is the most frequently performed general surgical procedure. Bile duct injury is a dreaded complication and is associated with serious long-term morbidity. PATIENTS AND METHODS: Three hundred patients with postcholecystectomy benign biliary strictures were managed from January 1989 to February 2004 at a tertiary care unit in northern India. Demographic data, clinical presentation, and immediate- and long-term results of surgical repair are analyzed from a prospective database. RESULTS: The time from cholecystectomy (open, n = 262; laparoscopic, n = 38) to stricture repair ranged from 0.2 to 360 (median 7) months. Thirty-six patients (12%) had prior stricture repair. Bismuth classification of the bile duct strictures was 32 type I, 113 type II, 126 type III, 18 type IV, and 11 type V. Two hundred and ninety-two patients (97%) underwent repair by a Roux-en-Y hepaticojejunostomy. One hundred patients (33.3%) had postoperative morbidity following stricture repair. Four patients (1.3%) died during the postoperative period. Of the 149 patients with a minimum available follow-up period of 5 years (mean 9.5, median 9.4 years; range 5-15.4 years), 134 (90%) had an excellent outcome (grade A, n = 122; grade B, n = 12); only 8 patients (5.4%) had a poor outcome. CONCLUSION: Excellent long-term outcomes with minimal morbidity and mortality can be achieved in the subgroup of benign biliary strictures managed in dedicated units with meticulous attention to the central tenets of biliary surgery.

Adolescent↗
PubMed2006

Neuroprotective effects of resveratrol against intracerebroventricular colchicine-induced cognitive impairment and oxidative stress in rats.

Alzheimer's disease is a complex and multifactorial neurodegenerative disease. Central administration of colchicine, a microtubule-disrupting agent, causes loss of cholinergic neurons and cognitive dysfunction that is associated with excessive free radical generation. The present study was aimed at evaluating the effects of trans-resveratrol in the prevention of colchicine-induced cognitive impairment and oxidative stress in rats. Intracerebroventricular administration of colchicine (15 microg/5 microl) induced impaired cognitive functions in both the Morris water maze task and the elevated plus-maze task. Chronic treatment with resveratrol (10 and 20 mg/kg, p.o.) for a period of 25 days, beginning 4 days prior to colchicine injection, significantly improved the colchicine-induced cognitive impairment. Intracerebroventricular colchicine injection resulted in free radical generation characterized by alterations in oxidative stress markers with a significant increase in malondialdehyde (MDA) and nitrite levels and depletion of reduced glutathione (GSH) activity in the rat brains. It also showed a significant decrease in acetylcholinesterase activity. Besides improving cognitive dysfunction, chronic administration of resveratrol significantly reduced the elevated MDA and nitrite levels and restored the depleted GSH and acetylcholinesterase activity. Results of the present study indicated that trans-resveratrol has a neuroprotective role against colchicine-induced cognitive impairment and associated oxidative stress.

Acetylcholinesterase↗
PubMed2006

Umbilical CSF fistula: a rare complication of ventriculoperitoneal shunt.

An umbilical CSF fistula following a ventriculoperitoneal shunt is an extremely rare complication. We report a 28-year-old man who presented with leak of clear fluid from the umbilicus, one month after a ventriculo-peritoneal shunt revision. Shuntogram revealed communication between umbilicus and abdominal end of the catheter. He was managed successfully with shunt exteriorization, antimeningitic treatment, and later shunt re-insertion.

Abdominal Injuries↗
PubMed2006

Interaction of lead with some essential trace metals in the blood of anemic children from Lucknow, India.

BACKGROUND: The effects of lead on the hematological system results in the inhibition of heme synthesis and in anemia. Lead may affect the absorption and metabolism of essential trace metals also. There is little information especially from the northern region of India regarding the relationship between blood lead levels>or=10 microg/dl and anemia in children. We performed a cross-sectional study to evaluate the association of blood lead levels>or=10 microg/dl with anemia, and its effect on hematological system and some essential trace metals in children. METHODS: A total of 75 children aged 1-7 years, 50 anemic (Hb 8 g%), drawn from Lucknow, India and nearby areas were recruited to determine blood levels of lead, iron, zinc, copper, and calcium along with hematological parameters [delta-aminolevulinic acid dehydratase (delta-ALAD) hemoglobin (Hb), hematocrit, and ascorbic acid]. RESULTS: Based on Centre for Disease Control and Prevention's intervention level of blood lead, children were categorized into those with blood lead<10 microg/dl (6.89+/-2.44) (n=19) (GI) and those with blood lead<10 microg/dl (21.86+/-7.58) (n=56) (GII). After adjustment for child's age, sex, and area of residence, children with blood lead levels>or=10 microg/dl were 2.87 (95% CI: 1.60-2.87) times as likely to have anemia as children with blood lead levels<10 microg/dl. The differences of the adjusted mean values of Hb, delta-ALAD, and hematocrit were significantly lower in children from the GII group when compared to children from the GI group (p<0.01, p<0.01, and p<0.05, respectively). Among essential trace metals, adjusted mean levels of blood iron, zinc, and calcium were significantly lower in GII as compared to GI (P<0.05 each). There were significant negative correlations of blood lead levels with delta-ALAD (r=-0.612, p<0.01), hematocrit (r=-0.427, p<0.05), iron (r=-0.552, p<0.05) zinc (r=-0.427, p<0.05), and calcium (r=-0.324, p<0.05). CONCLUSION: Results indicate that elevated blood lead levels (>or=10 microg/dl) in children were significantly associated with risk of anemia and that blood lead levels also influenced the status of essential trace metals. However, results of this study may be limited due to limited sample size but certainly form the basis of a larger sample size study, taking into account all the known potential confounders of anemia in children.

Anemia↗
PubMed2006

Salter-Harris type III fracture of the lateral femoral condyle with a ruptured posterior cruciate ligament: an uncommon injury pattern.

We report a case of an obscure injury to the distal femoral epiphysis with an uncommon pattern in a 12-year-old boy following a road traffic accident. Initial plain radiographs of the knee were inconclusive. Further investigation with magnetic resonance imaging revealed Salter-Harris type III fracture of the lateral femoral condyle with a gap at the fracture site associated with avulsion of the posterior cruciate ligament. This potentially serious injury can be underestimated on plain radiographs and therefore any suspected injury to the distal femoral epiphysis should be thoroughly assessed and investigated to institute appropriate treatment and minimise the risk of long-term complications.

Accidents, Traffic↗
PubMed2006

Autosomal dominant dystonia-plus with cerebral calcifications.

OBJECTIVE: To report genealogic, clinical, imaging, neuropathologic, and genetic data from a Canadian kindred with dystonia and brain calcinosis originally described in 1985. METHODS: The authors performed clinical examinations and CT and PET studies of the head and analyzed blood samples. One autopsy was performed. RESULTS: The family tree was expanded to 166 individuals. No individuals were newly affected with dystonia, but postural tremor developed in two. The mean age at symptom onset was 19 years. Eight individuals had dystonia: three focal, one segmental, one multifocal, and three generalized. Seven displayed additional signs: chorea, intellectual decline, postural tremor, and dysarthria. CT studies were performed on five affected and 10 at-risk family members. All affected individuals and eight at-risk individuals had brain calcinosis. PET scans in two individuals showed reduced D(1)- and D(2)-receptor binding and reduced uptake of 6-[(18)F]fluoro-l-dopa. Autopsy of one affected individual showed extensive depositions of calcium in the basal ganglia, thalamus, cerebral white matter, and cerebellum. No specific immunohistochemistry abnormalities were seen. Genome search data showed no evidence of linkage to the previously described loci IBGC1, DYT1, and DYT12. CONCLUSIONS: The phenotype of this family consists of dystonia-plus syndrome. Brain calcium deposits vary in severity and distribution, suggesting that calcifications alone are not entirely responsible for the observed clinical signs. Further studies are needed to elucidate the etiology of this heterogeneous group of disorders.

Adolescent↗
PubMed2006

Synthesis and anticonvulsant activity of some potential thiazolidinonyl 2-oxo/thiobarbituric acids.

A series of 5-[(N-substituted benzylidenylimino)amino]-2-oxo/thiobarbituric acids (3a-3h) have been synthesized by the condensation of 5-hydrazino-2-oxo/thiobarbituric acids (2a-2b) with various aromatic aldehydes. Cycloaddition of thioglycolic acid to 3a-3h, yielded 5-[(2'-substituted phenyl-4'-oxothiazolidin-3'-yl)amino]-2-oxo/thiobarbituric acids (4a-4h). All these compounds were screened, in vivo, for their anticonvulsant activity and acute toxicity studies. Compounds 4f and 4g were found to be most potent compounds of this series and were compared with the reference drugs, phenytoin sodium, lamotrigine and sodium valproate. The structures of these compounds have been established by IR, 1H NMR and mass spectroscopic data.

Animals↗
PubMed2006

Identification of mixed-symmetry states in an odd-mass nearly spherical nucleus.

The low-spin structure of 93Nb has been studied using the (n,n'gamma) reaction at neutron energies ranging from 1.5 to 3 MeV and the 94Zr(p,2ngamma)93Nb reaction at bombarding energies from 11.5 to 19 MeV. States at 1779.7 and 1840.6 keV, respectively, are proposed as mixed-symmetry states associated with the pi2p(1/2)-1x(2(1),MS+,94Mo) coupling. These assignments are derived from the observed M1 and E2 transition strengths to the 2p(1/2)-1x(2(1)+,94Mo) symmetric one-phonon states, energy systematics, spins and parities, and comparison with shell model calculations.

Journal Article↗
PubMed2006

Perforin polymorphism A91V and susceptibility to B-precursor childhood acute lymphoblastic leukemia: a report from the Children's Oncology Group.

Perforin plays a key role in the cytotoxicity of natural killer and cytotoxic T cells. Genetic mutations in the perforin gene (PRF1) give rise to approximately 30% cases of familial hemophagocytic lymphohistiocytosis. A frequent polymorphism, A91V (C to T transition at position 272), may impair processing of perforin protein to the active form, and has been suggested to increase susceptibility to childhood acute lymphoblastic leukemia (ALL). To investigate the role of A91V in ALL, we genotyped 2272 children with de novo ALL registered on the Pediatric Oncology Group ALL Classification study P9900 and 655 normal controls. Allele frequencies in the controls showed a very low frequency of the variant allele in blacks, 0.7% compared to 4% in white controls. In light of this, analysis was restricted to a comparison of white cases and controls only. Overall genotype frequencies were similar in white ALL cases and normal white controls (P=0.58), indicating that in contrast to the previous report, A91V polymorphism is not associated with increased risk of childhood ALL. PRF1 A91V frequency was significantly increased in children with BCR-ABL positive ALL (24 vs 8.5%; P=0.0048); however, this observation includes a relatively small number of cases and needs further exploration.

Base Sequence↗
PubMed2006

Synthesis and QSAR studies on 5-[2-(2-methylprop1-enyl)-1H benzimidazol-1yl]-4,6-diphenyl-pyrimidin-2-(5H)-thione derivatives as antibacterial agents.

A new series of 5-[2-(2-methylprop1-enyl)-1H benzimidazol-1yl]-4,6-diphenyl-pyrimidin-2-(5H)-thione derivatives [3a-q] has been synthesized and subjected to evaluate their antibacterial properties. All the synthesized compounds of the series displayed, remarkable activity in comparison to standard drug (ampicillin). A number of descriptors were tested to adjudge a quantitative correlation between activity and structural features. However, significant correlations have emerged between activity and physicochemical parameters viz. polarizability parameter (MR). Moreover, results are interpreted on the basis of multiple regression and cross-validation methodology.

Anti-Bacterial Agents↗
PubMed2006

Palliative care for prenatally diagnosed lethal fetal abnormality.

Diagnosis of lethal fetal abnormality raises challenging decisions for parents and clinicians. Most parents opt for termination, which may include feticide. Advances in imaging seem unlikely to lead to earlier diagnoses. Perinatal palliative care offers an alternative. Parental decision making and the clinical aspects of perinatal palliative care were studied after a prenatal diagnosis of lethal fetal abnormality in 20 pregnancies. 40% of parents chose to continue the pregnancy and pursue perinatal palliative care. Six of these eight babies were liveborn and lived for between 1(1/2) h and 3 weeks.

Decision Making↗
PubMed2006

Childhood aplastic anaemia in Lucknow, India: incidence, organochlorines in the blood and review of case reports following exposure to pesticides.

OBJECTIVES: A hospital-based case-control study, the first in India, was conducted to determine the incidence of childhood aplastic anaemia in and around Lucknow in the backdrop of organochlorine levels in the blood and review the database for any association between the disease and exposure to pesticides. DESIGN AND METHODS: A total of 25 cases of childhood aplastic anaemia were identified as per established criteria and enrolled over the study period of 1 year. Their blood organochlorine levels were determined using a gas-liquid chromatograph equipped with an electron capture detector. RESULTS: The annual incidence of childhood aplastic anaemia in and around Lucknow was found to be 6.8 cases per million which is higher than many countries (e.g., France, Brazil, UK, and United States) but lower than those reported in Sweden, China and an European-Israeli collaborative study. Blood levels of alpha-HCH, gamma-HCH, delta-HCH, total-HCH, and p, p'-DDE were higher in children with aplastic anaemia than in those of controls; only alpha-HCH differed significantly (P < 0.05). CONCLUSIONS: Although this pilot study, with limited statistical power, did not support any association between exposure to organochlorines and risk of childhood aplastic anaemia, a possible association between the two could not be ruled out in view of several cases identified following exposure to pesticides.

Anemia, Aplastic↗
PubMed2006

Antiparasitic activity of aromatic diamidines is related to apoptosis-like death in Trypanosoma cruzi.

Two aromatic diamidines, furamidine (DB75) and its phenyl-substituted analogue (DB569), which exhibit trypanocidal activity, were assayed against Trypanosoma cruzi and were found to induce apoptosis-like death characteristics such as nuclear DNA condensation and fragmentation, decreased mitochondrial membrane potential and phosphatidylserine exposure. DB569 displays superior trypanocidal activity compared to furamidine and also had higher ability to induce apoptosis-like death in treated parasites. The present results showing apoptosis-like death in T. cruzi after treatment with both DB75 and DB569 make important contributions to the understanding of the mechanisms of the aromatic diamidines, which represent promising trypanocidal compounds.

Animals↗
PubMed2006

Anterior cruciate ligament reconstruction using hamstring tendon graft without detachment of the tibial insertion.

INTRODUCTION: We report results of the anterior cruciate ligament reconstruction using a four-strand hamstring graft without detachment of the tibial insertion of the tendons. MATERIAL AND METHODS: In 74 patients the hamstring graft was fixed using an endobutton on the femoral side and a barbed staple on the tibial side. There were 69 male and 5 female patients. The mean age at the time of operation was 35.1 years (21-53 years). Postoperatively, an accelerated rehabilitation was followed with no protective braces. The mean follow-up period was 64 months (range 48 to 84 months). RESULTS: All patients achieved full range of motion with a stable knee joint. The mean side-to-side difference using KT-1000 was 1.43 mm (SD 3.86). The average Lysholm score improved from 42 to 79.2 and the Tegner score improved from 3.4 to 5.9. CONCLUSION: Detachment of hamstring tendons from their tibial insertion is unnecessary and our results with accelerated rehabilitation without protective braces are satisfactory and comparable to other studies.

Adult↗