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Biomedical subjects

S Gupta

Publications and source records attributed to S Gupta.

At least 613 records · Page 34Linked to original sources
PubMed1998

Increased apoptosis of T cell subsets in aging humans: altered expression of Fas (CD95), Fas ligand, Bcl-2, and Bax.

Aging is associated with lymphopenia and progressive decline in T cell functions; however, the mechanisms underlying these defects are unclear. We analyzed the expression of genes promoting apoptosis (fas/fasL1 and bax) and those inhibiting apoptosis (bcl-2 and bcl-xL) in lymphocytes from aging and young subjects at the protein level, using flow cytometry/Western blotting, and at the mRNA level, using quantitative PCR. Susceptibility of T cell subsets to undergo anti-Fas-induced apoptosis was analyzed by propidium iodide staining, TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) assay, DNA fragmentation assay, and staining with Hoechst 33342 dye. An increased expression of Fas and Fas ligand and a decreased expression of Bcl-2 were observed in both CD4+ and CD8+ T cells from aging as compared with young controls. Increased Fas and decreased Bcl-2 expression were also found in memory cells of both CD4+ and CD8+ T cell subsets from aging. Bax expression was increased in lymphocytes from aging at both the protein and mRNA level. No significant difference was observed in Bcl-xL expression between aging and young; however, the ratio of Bax:Bcl-xL was increased in aging. An increased proportion of CD4+ and CD8+ T cell subsets from aging underwent apoptosis following anti-Fas Ab treatment as compared with CD4+ and CD8+ T cell subsets from young controls. These data suggest that increased apoptosis may be one of the mechanisms responsible for lymphopenia and T cell deficiency associated with human aging.

Adult↗
PubMed1998

Liver repopulation with xenogenic hepatocytes in B and T cell-deficient mice leads to chronic hepadnavirus infection and clonal growth of hepatocellular carcinoma.

To investigate host and viral mechanisms determining hepadnaviral persistence and hepatocarcinogenesis, we developed a mouse model by transplanting woodchuck hepatocytes into the liver of mice that contain the urokinase-type plasminogen activator transgene (uPA) and lack mature B and T lymphocytes due to a recombination activation gene 2 (RAG-2) gene knockout. The woodchuck hepatocytes were transplanted via intrasplenic injection and were found to integrate into the recipient mouse liver cord structure. Normal adult woodchuck hepatocytes proliferated and reconstituted up to 90% of the uPA/RAG-2 mouse liver. uPA/RAG-2 mice containing woodchuck hepatocytes were infectable with woodchuck hepatitis virus (WHV) and showed WHV replication for at least 10 months with titers up to 1 x 10(11) virions per ml in the peripheral blood. WHV-infected hepatocytes from chronic carrier woodchucks also established a persistent infection in uPA/RAG-2 mice after an 8- to 12-week lag period of viremia. Although WHV envelope, core, and X proteins were produced in the uPA/RAG-2 mice, no inflammatory host immune response was observed in the liver of WHV-replicating mice. A first antiviral test demonstrated a greater than four orders of magnitude drop in WHV titer in response to interferon alpha treatment. WHV replication was up-regulated by dexamethasone treatment. Comparison of precancerous lesions in donor woodchucks versus recipient uPA/RAG-2 mice revealed an enrichment of dysplastic precancerous hepatocytes in transplanted mice. Clonal amplification of hepatocytes from a woodchuck with hepatocellular carcinomas was demonstrated by the detection of unique WHV DNA integration patterns in hepatocellular carcinomas that arose in uPA/RAG-2 mice. In the absence of B or T cell-mediated immune responses, WHV establishes a persistent noncytotoxic infection of woodchuck hepatocytes in uPA/RAG-2 chimeric mouse livers. Further studies of the kinetics of hepadnavirus infection and replication in quiescent and proliferating hepatocytes should increase our understanding of hepadnavirus spread and aid in the design of therapies to block or cure persistent infection.

Animals↗
PubMed1998

Treatment of in-stent restenosis with high speed rotational atherectomy and IVUS guidance in small <3.0 mm vessels.

The management of in-stent restenosis remains a subject for debate because no one revascularization option is considered the most appropriate. Since a high restenosis rate still occurs after repeat balloon angioplasty, new techniques are attempted in order to reduce this rate. A combination of high speed rotational atherectomy (HSRA) and adjunctive balloon angioplasty is likely to achieve good results. In small (<3.0 mm diameter) vessels, the risk of interaction between the burr and the stent increases. We thus used intravascular ultrasound (IVUS) guidance in the treatment of in-stent restenosis with HSRA in small <3.0 mm small diameter vessels. Nine patients with in-stent restenosis in small vessels were referred for repeat angioplasty. Initial IVUS examination was used to assess the minimal stent struts diameter and to guide the burr size selection. A combination of HSRA and additional balloon angioplasty was performed under IVUS and angiographic guidance. Mean angiographic reference diameter was 2.25 +/- 0.35 mm and mean stent struts diameter was 2.38 +/- 0.20 mm. Burr size was selected approximately 0.5 mm smaller than stent struts diameter and ranged from 1.75 to 2.5 mm, with a 0.88 +/- 0.12 mean burr/artery ratio (range 0.71, 1.08). In two patients, a second larger burr was used. In 4/9 patients, the burr size chosen under IVUS guidance was close to angiographic MLD at stent implantation and thus larger than what would be used without IVUS guidance. Additional balloon angioplasty was decided in all cases, using a 1.1 +/- 0.15 balloon/artery ratio. No complication occurred. Mean relative gain in minimal lumen diameter (MLD) was 94 +/- 90% after HSRA and 54 +/- 34% after balloon angioplasty (total relative gain 180 +/- 100%). IVUS guidance allowed safe management of in-stent restenosis in small vessels using combination of HSRA and balloon angioplasty. Long-term follow-up and comparison with other techniques are necessary to assess whether this technique should be used routinely.

Adult↗
PubMed1998

Coronary stent for variant angina: atypical presentation.

Pharmacological therapy remains the treatment of choice for Prinzmetal angina. We report an unconventional approach of coronary artery stenting to treat coronary artery spasm in variant angina refractory to triple drug therapy. Favorable clinical and angiographic results and a negative Ergonovine test, under less aggressive medical therapy, are valuable arguments for stenting. Four-month angiographic follow-up showed absence of intrastent restenosis with a negative Ergonovine test. However, long-term follow-up is necessary before advocating this as a systematic approach.

Adult↗
PubMed1998

Assessment of copper and zinc status in hair and urine of young women descendants of NIDDM parents.

The concentration of copper (Cu) and zinc (Zn) in hair and urine were studied in young nonpregnant healthy women whose both parents were diagnosed for noninsulin-dependent diabetes mellitus (NIDDM descendants) and were compared with those of young healthy nonpregnant females with no family history of NIDDM or hypertension (non-NIDDM descendants) and NIDDM patients. The concentration of Zn in hair in NIDDM descendants was significantly higher than that of non-NIDDM descendants (p < 0.001) and insignificantly higher than that of NIDDM patients. The hair Cu concentrations in NIDDM descendant and patients were significantly lower than that of non-NIDDM descendants (p < 0.001). Hyperzincuria was detected in some NIDDM patients and hypocuperuria in all NIDDM descendants and patients. The data suggest that the young healthy NIDDM descendants possess high-Zn and low-Cu reserves in their bodies, and the observed perturbation appears to be associated with Cu-Zn antagonism.

Adult↗
PubMed1998

Confirmation of epidural catheter placement using nerve stimulation.

PURPOSE: To examine the reliability of low current electrical epidural stimulation to confirm epidural catheter placement. METHODS: Forty patients with epidural catheters (19G Arrow Flextip plus) already in place for post-operative pain management were studied. An adapter (Arrow-Johans ECG Adapter) was attached to the connector of the epidural catheter. The epidural catheter and adapter were filled with normal saline. The cathode lead of the nerve stimulator was attached to the metal hub of the adapter. Catheter placement was judged to be correct or incorrect, depending upon the presence or absence of truncal or limb movement to 1 Hz stimulation (1-10 mA). A standard test dose (3 ml lidocaine 1.5% with 1:200,000 epinephrine) was then injected. The efficacy of the epidural morphine was assessed independently. RESULTS: The sensitivity and specificity of the test was 100% and 91.6% compared with the standard test dose. The positive and negative predictive value was 96% and 100%. In predicting the clinical effect of epidural morphine, the sensitivity and specificity was 96.1% and 76.9%. The positive and negative predictive value was 89% and 90%. The correlation of unilateral or bilateral motor response from the test and sensory response from the lidocaine test with sensitivity and specificity was 91.6% and 53.0%. The predictive value for unilateral response was 61% and for bilateral was 88%. CONCLUSION: This study establishes this test as a simple, objective and reliable technique for confirmation of epidural catheter placement.

Analgesia, Epidural↗
PubMed1998

A rapid precurarization technique using rocuronium.

PURPOSE: To evaluate a rapid and time-saving precurarization technique using rocuronium to prevent succinylcholine-induced myalgia. METHOD: In a prospective, double blind randomized study, 42 ASA 1-2 patients were assigned to one of three pretreatment groups: 0.01 ml.kg-1 normal saline, 0.1 mg.kg-1 atracurium, and 0.1 mg.kg-1 rocuronium. Anaesthesia commenced with 1.5 micrograms.kg-1 fentanyl and 0.5 mg.kg-1 lidocaine at time zero. Pretreatment was administered 60 sec later, followed by 2.5 mg.kg-1 propofol. At 90 sec, 1.5 mg.kg-1 succinylcholine was injected and 30 sec later, the trachea was intubated and the ease of intubation was graded. The patient was observed for the presence and severity of fasciculations. Myalgias were recorded on postoperative days 1, 2 and 7. RESULTS: The incidence of fasciculations in the rocuronium group (21.4%) was lower (P < 0.001) than atracurium (78.5%) or placebo (92.8%) groups. On postoperative day 1, the incidence of postoperative myalgia in the rocuronium group (14.2%) was less than the placebo group (78.2%; P < 0.002) and atracurium group (85.7%; P < 0.001). The incidence of myalgia in the rocuronium group (7.1%) was lower than in the placebo group (78.5%; P < 0.001) but not different from the atracurium group (42.8%; P = 0.077) on postoperative day 2. On postoperative day 7, there was no difference among the three groups. Fasciculations were related to postoperative myalgia. There was no difference in intubating conditions among the three groups. CONCLUSION: Rocuronium pretreatment given just before induction of anaesthesia with propofol reduces fasciculations and succinylcholine-induced myalgia.

Adult↗
PubMed1998

Ilio-psoas abscess in the paediatric population: treatment by US-guided percutaneous drainage.

BACKGROUND: Image-guided percutaneous drainage has been shown to be a safe and effective alternative to surgery in the management of psoas abscess in adults and adolescents. There is little information on its use in children. OBJECTIVE: To evaluate the safety and efficacy of US-guided percutaneous needle aspiration and catheter drainage of ilio-psoas abscesses. MATERIALS AND METHODS: A retrospective review of 14 children with 16 ilio-psoas abscesses (10 pyogenic and 4 tuberculous) who were treated by US-guided percutaneous needle aspiration (n = 5) or catheter drainage (n = 9) along with appropriate antimicrobial therapy. RESULTS: Percutaneous treatment was successful in 10 of the 14 patients; all showed clinical improvement within 24-48 h of drainage and subsequent imaging demonstrated resolution of the abscess cavities. Surgery was avoided in all of these ten patients except one, who underwent open surgical drainage of ipsilateral hip joint pus. Of the other four patients, two had to undergo surgical drainage of the ilio-psoas abscesses after failure of percutaneous treatment, one improved with antibiotics after needle aspiration failed to yield any pus, and one died of continuing staphylococcal septicaemia within 24 h of the procedure. There were no procedural complications. CONCLUSIONS: Percutaneous drainage represents an effective alternative to surgical drainage as a supplement to medical therapy in the management of children with ilio-psoas abscesses.

Child↗
PubMed1998

Acute renal failure in bilateral urinary tract tuberculosis.

A case of bilateral urinary tract tuberculosis presenting with acute renal failure is reported. It is believed to be the first reported instance of the disease presenting in this form. The patient was managed with preliminary high diversion followed by bilateral replacement of the ureters with ileal loops that were anastomosed end-to-side and then implanted into the bladder.

Acute Kidney Injury↗
PubMed1998

Intestinal obstruction caused by caecal volvulus.

The case of a 6-month-pregnant woman who had an uneventful postoperative recovery and normal vaginal delivery following a right hemi-colectomy for volvulus of the caecum with gangrene is reported.

Adult↗
PubMed1998

Potential utility of recombinant human GM-CSF as adjunctive treatment of refractory oropharyngeal candidiasis in AIDS patients.

The aim of the study was to investigate the use of granulocyte macrophage-colony stimulating factor (GM-CSF) as an adjunctive treatment for clinically refractory mucosal candidiasis in patients with advanced AIDS. Three patients with advanced AIDS and oropharyngeal candidiasis clinically refractory to azoles or amphotericin B received GM-CSF for 14 days along with either fluconazole or amphotericin B. All three patients showed clinical improvement and mycological improvement without any adverse events. Thus, GM-CSF may be a possible alternative as adjunctive therapy in the management of refractory mucosal candidiasis in patients with advanced AIDS.

AIDS-Related Opportunistic Infections↗
PubMed1998

Congenital pouch colon revisited.

BACKGROUND/PURPOSE: The authors' recent experience with the study of the presentation, the pathological anatomy, and results of management of congenital pouch colon (CPC) malformations is presented. The possible embryogenesis of this condition is discussed. METHODS: Between January 1991 and June 1997, CPC with anorectal agenesis was diagnosed in 39 patients, 27 boys and 12 girls, who were classified in four groups, based on the length of the normal colon proximal to the distended segment. In 31 patients with little or no normal colon, the choice of primary procedure was based on the condition of the infant and the viability of the colonic pouch. Definitive surgery has been performed in 15 patients from this group. The eight patients with a suitable length of normal colon had a lower level of termination of the colonic pouch and a lower fistula. In these, a colostomy was constructed just proximal to the pouch, with later definitive surgery in four patients consisting of excision of the colonic pouch and pull-through of the proximal colon. RESULTS: Mortality after primary surgery was 13%. Definitive surgery was well tolerated in all 19 patients. CONCLUSION: In patients in whom a tubularized segment of the colonic pouch was used, continence was only fair to poor a year later.

Colon↗
PubMed1998

Excitotoxic lesions of the subthalamic nucleus ameliorate asymmetry induced by striatal dopamine depletion in the rat.

We investigated the effect of unilateral dorsal striatal dopamine depletion (by intrastriatal infusion of 6-OHDA), ibotenic acid lesions of the subthalamic nucleus (STN) and combined dopamine depletion and STN lesions on sensorimotor asymmetry using a test of somatosensory asymmetry [T. Schallert et al., Pharmacol. Biochem. Behav. 16 (1982) 455-462]. The unilateral striatal dopamine depletion resulted in a somatosensory asymmetry. This asymmetry was ameliorated in the rats with combined dopamine depletion and STN lesion. indicating the potential beneficial nature of STN inactivation in rats with striatal dopamine depletion.

Animals↗