Search PubMed⌕ Search

Biomedical subjects

A Gupta

Publications and source records attributed to A Gupta.

At least 361 records · Page 20Linked to original sources
PubMed1999

A time course study for the development of an immunocompromised wound model, using hydrocortisone.

Although wound healing is essentially a physiologic process, some chronic wounds exhibit considerable delay in healing. Often these do not heal perfectly in individuals with low immune profiles. Thus, the present study was undertaken to develop an excision wound model in the immunocompromised state induced by pretreatment with hydrocortisone (HC) 40 mg/kg intramuscularly in male rats. Wounds of 8-mm diameter were made on the preshaved dorsal surface of rats using an Acuderm biopsy punch, following pretreatment with HC. After 14 days HC-treated animals exhibited atrophy of spleen and adrenal glands and a significant reduction of circulating lymphocytes and increase in neutrophils; these changes are indicative of immunosuppressive state of animals. The cell proliferation was significantly affected as shown by decreases in DNA (23%) and protein (11%). Furthermore, there were also significant reductions in tensile strength (37%) and hydroxyproline (33%) contents. These results were further supported by lack of contraction of wound edges. It is concluded that animals primed with HC 1 week prior to wounding developed prolonged immunosuppression, which significantly impaired the wound healing as compared with other groups. Thus, this can be experimentally employed as an immunocompromised wound model for evaluating compounds as novel wound healers suitable for immunocompromised subjects.

Adrenal Glands↗
PubMed1999

Inhibition of DNA synthesis in Caco-2 cells by oxidative stress: amelioration by epidermal growth factor.

The role of oxidative stress in the regulation of intestinal epithelial proliferation was examined by evaluating the effect of H2O2 and xanthine oxidase + xanthine (XO + X) on [3H]thymidine incorporation into DNA in Caco-2 cells. DNA synthesis was highest 4 and 5 days after seeding, while it declined rapidly between 5 and 12 days. Pretreatment for 0.5-24 h with H2O2 or XO + X reduced DNA synthesis on 4- to 6-day-old, but not on 7- to 20-day-old cells. The effect of XO + X on DNA synthesis was significantly reduced by catalase, superoxide dismutase, and ferric chloride, but pretreatment with deferoxamine potentiated XO + X-induced inhibition of DNA synthesis. Coadministration of epidermal growth factor (EGF) for 24 hr reduced the H2O2 and XO + X-induced inhibition of DNA synthesis; this effect of EGF was not observed up to 8 hr. Results show that O2- and H2O2 rapidly inhibit DNA synthesis in Caco-2 cells and that EGF restores DNA synthesis in oxidant-treated cells.

Caco-2 Cells↗
PubMed1999

Mycotic keratitis in non-steroid exposed vernal keratoconjunctivitis.

PURPOSE: To report a patient with vernal keratoconjunctivitis who developed mycotic keratitis in absence of known risk factors. METHODS: A 17-year-old male suffering from vernal keratoconjunctivitis presented with infective keratitis. The patient had been treated in the past with topical antihistaminics and vasoconstrictors. The patient had not been exposed to topical steroids in 2 years of follow-up. He did not have dry eye or corneal micro or macroerosions prior to the development of infective keratitis. Corneal scrapings were obtained and subjected to KOH wet mount smear, calcofluor and Grams stain as well as bacterial culture sensitivity and fungal culture. RESULTS: Clinical diagnosis of mycotic keratitis in association with vernal conjunctivitis was supported by microbiological investigations. KOH wet mount and calcofluor staining showed presence of filamentous septate hyphae while fungal culture showed growth of aspergillus fumigatus. Antifungal therapy was initiated in the form of topical natamycin 5% suspension to which the patient responded and recovered 6/6 final visual acuity. CONCLUSION: The authors wish to conclude that patients suffering from vernal keratoconjunctivitis, even in the absence of corneal involvement, steroid exposure and trauma, may be at increased risk of developing keratomycosis.

Adolescent↗
PubMed1999

Efficacy of supratarsal dexamethasone versus triamcinolone injection in recalcitrant vernal keratoconjunctivitis.

PURPOSE: To compare the efficacy of supratarsal injection of short acting dexamethasone sodium phosphate versus intermediate acting triamcinolone acetonide as a new therapeutic modality for treating eyes with recalcitrant vernal keratoconjunctivitis (VKC). METHODS: The study was a prospective, randomized, double blind, case controlled trial, including 38 eyes of 19 patients with recalcitrant VKC. Except for two initial patients who received supratarsal injection of triamcinolone acetonide in both the eyes, one eye of each patient was randomly assigned to receive either 2 mg of dexamethasone sodium phosphate or 20 mg of triamcinolone acetonide. RESULTS: Both the drugs were equally effective with no statistically significant difference in the mean time of resolution of cobblestone papillae, limbal edema, shield ulcer, SPK and relief of symptoms. The recurrence rate of disease was, however, lower following triamcinolone acetonide injection. CONCLUSIONS: Supratarsal injection of corticosteroid is a cheap, effective and safe modality of treatment for managing eyes with recalcitrant VKC. Both short acting dexamethasone and intermediate acting triamcinolone acetonide are equally effective.

Adolescent↗
PubMed1999

Molecular basis for resistance to silver cations in Salmonella.

Here we report the genetic and proposed molecular basis for silver resistance in pathogenic microorganisms. The silver resistance determinant from a hospital burn ward Salmonella plasmid contains nine open reading frames, arranged in three measured and divergently transcribed RNAs. The resistance determinant encodes a periplasmic silver-specific binding protein (SilE) plus apparently two parallel efflux pumps: one, a P-type ATPase (SilP); the other, a membrane potential-dependent three-polypeptide cation/proton antiporter (SilCBA). The sil determinant is governed by a two-component membrane sensor and transcriptional responder comprising silS and silR, which are co-transcribed. The availability of the sil silver-resistance determinant will be the basis for mechanistic molecular and biochemical studies as well as molecular epidemiology of silver resistance in clinical settings in which silver is used as a biocide.

ATP Binding Cassette Transporter, Subfamily B↗
PubMed1999

Urinary sodium excretion and blood pressure in chronic psychiatric in-patients.

Studies of populations or communities with no rise in blood pressure (BP) with advancing age and low prevalence of hypertension, may provide aetiological clues on the cause of hypertension. Within westernised societies, low blood pressures have been reported amongst chronic psychiatric in-patients and closed order secluded nuns. To investigate factors associated with BP in chronic psychiatric in-patients, we surveyed the BP and lifestyle factors in 89 such subjects in low security wards in three psychiatric hospitals. The average age of examines was 48.1 years (s.d. 15.8) and the patients had been in hospital for a mean of 8.6 years (range 1.1 to 51.7 years). The mean systolic and diastolic blood pressures of this group were 122.0 mm Hg (s.d. 14.2) and 76.9 mm Hg (s.d. 8.5) respectively. This was lower than pressures obtained when they were admitted to hospital (mean systolic BP change -17.1 mm Hg (s.d. 14), paired t-test P < 0.001; mean diastolic BP change -3.7 mm Hg (s.d. 12.2), paired t-test P < 0.001). BP at examination was significantly correlated with the urinary sodium to creatinine ratio (r = 0.302, P = 0.027), but not with the urinary sodium or potassium concentrations or potassium/creatinine ratio. The change in mean systolic BP (that is, the difference in BP between admission and examination) was significantly correlated with sodium/creatinine ratio (r = 0.62, P < 0.0001), urinary sodium concentration (r = 0.27, P = 0.045) and urinary sodium/potassium ratio (r = 0.36, P = 0.008). No relationship was found between BP and the nature of the psychiatric diagnosis or the type of psychotropic medication that was being prescribed. Stepwise multiple regression demonstrated that urinary sodium creatinine ratio and age were predictive of the change in systolic BP since admission to hospital. Our study confirms previous observations of lower mean systolic and diastolic blood pressures in chronic psychiatric subjects after a long in-patient stay. This fall is related to a low urine sodium excretion and suggests that a low dietary sodium intake may, in part, account for the low BP, or the difference between BP in the stressed and relaxed state, seen in these patients.

Adult↗
PubMed1999

Inhibition of apoptosis by ionomycin and zinc in peripheral blood mononuclear cells (PBMC) of leprosy patients.

PBMC from tuberculoid (BT/TT) and lepromatous leprosy (BL/LL) leprosy patients showed spontaneous apoptosis when cultured in the absence of mitogen for 24 h, which was inhibited by anti-tumour necrosis factor-alpha (TNF-alpha) antibodies. Apoptosis was also inhibited by ionomycin and zinc, which also increased IL-2 and decreased TNF-alpha production. The increase in IL-2 production suggests a mechanism whereby dietary supplements with zinc might alter the cell-mediated immunity response in leprosy patients.

Antibodies↗
PubMed1999

Role of abdominal drains in perforated duodenal ulcer patients: a prospective controlled study.

BACKGROUND: Duodenal ulcer perforation is a common emergency in south India, with about 100-120 cases being treated at Jawaharalal Institute of Post Graduate Medical Education and Research each year. The routine to date has been to leave two tube drains: one in the Morrison's pouch and one in the pelvis after omental patch closure. This study was conducted to test the efficacy and safety of drain usage routinely after duodenal ulcer perforation closure with Roscoe Graham omental patch technique. METHODS: In this prospective controlled study, 44 patients formed the test group (without drains) and 75 patients formed the control group (with abdominal drainage). Only patients of perforated duodenal ulcer closed with Roscoe Graham omental patch technique were included in the study. The incidence of postoperative fever, wound infection, time for return of bowel function and duration of hospital stay were noted. Details of drainage noted were the mean amount of daily drainage, mean time of drain removal and occurrence of drain-related complications. Peritoneal fluid, wound discharges, drain tips and drain wounds were cultured. Abdominal ultrasound was performed in all patients in the second postoperative week or if earlier indicated to detect intra-abdominal collections. RESULTS: It was found that there was no difference in incidence or duration of postoperative pyrexia, return of bowel function or postoperative hospital stay between the two groups. Routine use of drains was not effective in preventing postoperative fluid collection nor in decreasing the incidence of intra-abdominal abscesses. The migration of bacteria from the exterior to the peritoneal cavity via the drain was also demonstrated. Drains were found to cause morbidity including intestinal obstruction. CONCLUSION: The routine use of drains was found to be neither safe nor effective in patients of perforated duodenal ulcer treated by omental patch closure.

Adult↗
PubMed1999

Prevalence and determinants of hyperhomocysteinemia in hemodialysis and peritoneal dialysis.

BACKGROUND: Hyperhomocysteinemia is an independent risk factor for atherosclerotic complications in patients with end-stage renal disease, although the mechanisms remain unclear. The major determinants of plasma homocysteine concentration are usually folate, vitamin B12, pyridoxal 5'-phosphate (vitamin B6), and glomerular filtration rate. METHODS: We measured factors, including plasma folate, vitamin B12, vitamin B6, creatinine, as well as the dose and duration of dialysis, that might affect plasma homocysteine concentrations in 130 patients on hemodialysis (HD) and compared these observations with those in 46 patients on peritoneal dialysis (PD). Independent determinants of total homocysteine were identified using a multiple logistical regression analysis. RESULTS: Total homocysteine values averaged 29.8 mumol/liter in HD patients, significantly higher than the mean value of 19.9 mumol/liter observed in patients on PD (P < 0.001). The prevalence of hyperhomocysteinemia was 90.8% among HD patients, significantly higher than the prevalence of 67.4% among PD patients. Folate values in HD patients averaged 45.5 nmol/liter and were significantly lower than in PD patients (104.2 nmol/liter, P < 0.001). For patients on HD, the only determinant of total homocysteine concentration was plasma folate (r = -0.31, P < 0.001). In contrast, for PD patients, total homocysteine did not correlate with plasma folate, vitamin B12, or vitamin B6. CONCLUSIONS: Hyperhomocysteinemia is more prevalent and intense in HD patients compared with those on PD. The homocysteine response may become refractory to excess folate supplementation in PD patients.

Creatinine↗
PubMed1999

Dialysate iron therapy: infusion of soluble ferric pyrophosphate via the dialysate during hemodialysis.

BACKGROUND: Soluble iron salts are toxic for parenteral administration because free iron catalyzes free radical generation. Pyrophosphate strongly complexes iron and enhances iron transport between transferrin, ferritin, and tissues. Hemodialysis patients need iron to replenish ongoing losses. We evaluated the short-term safety and efficacy of infusing soluble ferric pyrophosphate by dialysate. METHODS: Maintenance hemodialysis patients receiving erythropoietin were stabilized on regular doses of intravenous (i.v.) iron dextran after oral iron supplements were discontinued. During the treatment phase, 10 patients received ferric pyrophosphate via hemodialysis as monthly dialysate iron concentrations were progressively increased from 2, 4, 8, to 12 micrograms/dl and were then sustained for two additional months at 12 micrograms/dl (dialysate iron group); 11 control patients were continued on i.v. iron dextran (i.v. iron group). RESULTS: Hemoglobin, serum iron parameters, and the erythropoietin dose did not change significantly from month 0 to month 6, both within and between the two groups. The weekly dose of i.v. iron (mean +/- SD) needed to maintain iron balance during month 6 was 56 +/- 37 mg in the i.v. iron group compared with 10 +/- 23 mg in the dialysate iron group (P = 0.001). Intravenous iron was required by all 11 patients in the i.v. iron group compared with only 2 of the 10 patients receiving 12 micrograms/dl dialysate iron. The incidence of adverse effects was similar in both groups. CONCLUSIONS: Slow infusion of soluble iron pyrophosphate by hemodialysis may be a safe and effective alternative to the i.v. administration of colloidal iron dextran in maintenance hemodialysis patients.

Adult↗
PubMed1999

Diagnostic efficacy of polymerase chain reaction in granulomatous uveitis.

SETTING: The granulomatous uveitis, multifocal choroiditis and periphlebitis have been suspected to be of tubercular origin but no definitive reports about detection of etiological agents have been documented in the literature. Conventional bacteriological methods are not generally helpful in diagnosing ocular tuberculosis due to difficulty with potential morbidity associated with obtaining the biopsy material from the eye. Thus, the diagnosis of ocular tuberculosis is most often presumptive. OBJECTIVE: We evaluated the role of polymerase chain reaction (PCR) for detection of Mycobacterium tuberculosis in the aqueous humor samples obtained from eyes with active uveitis. METHODS: Aqueous samples from 53 patients having cellular reaction in the anterior chamber along with any one or more of the following: 1) active vasculitis; 2) anterior vitreous cells; 3) snowball opacities; 4) snow banking in the pars plana; 5) retinochoroiditis were withdrawn by anterior chamber paracentesis and subjected to PCR. Seventeen samples from patients with definite clinical diagnoses other than tuberculosis formed a disease control group. Fifteen aqueous samples obtained from healthy subjects undergoing routine cataract surgery served as healthy controls. PCR was performed using primers capable of amplifying a 150 b.p. segment from a conserved repetitive sequence in the genome of M. tuberculosis. RESULTS: Twenty out of the 53 samples (37.7%) in the study group were positive where as only one sample out of 17 in the disease control group (5.7%) showed a weakly positive band. No sample from the healthy control group showed a positive PCR. CONCLUSION: Our study shows that PCR can be effectively used for the diagnosis of intraocular tuberculosis in the presence of uveitis.

Aqueous Humor↗
PubMed1999

Increased ROS levels contribute to elevated transcription factor and MAP kinase activities in malignantly progressed mouse keratinocyte cell lines.

There is evidence that reactive oxygen species (ROS) are important mediators of tumor promotion and progression. The molecular mechanisms involved in ROS-mediated signaling, however, are unclear at present. Using ionizing radiation and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) as model physical and chemical carcinogens, we have malignantly progressed 308 cells, a papilloma-producing mouse keratinocyte cell line, and investigated the molecular alterations in the progressed phenotypes. In this study, we demonstrate that both MNNG and radiation-progressed malignant variants showed elevated ROS levels that contributed to their proliferative capacity in vitro as well as in vivo. We found increased Erk-1/2 and p38 MAP kinase activities to be important components of ROS-mediated signaling. The pro-oxidant state also contributed to constitutive elevation of AP-1, NFkappaB and cAMP response element transactivation in the malignant phenotype. Our data provide evidence for a functional role of elevated ROS levels in tumor progression and implicate Erk-1/2 and p38 MAP kinase activation in the malignant progression of mouse keratinocytes.

Animals↗
PubMed1999

Okadaic acid mediates p53 hyperphosphorylation and growth arrest in cells with wild-type p53 but increases aberrant mitoses in cells with non-functional p53.

The protein phosphatase inhibitor and tumor promoting agent okadaic acid (OA), has been shown previously to induce hyperphosphorylation of p53 protein, which in turn correlated with increased transactivation or apoptotic function. However, how the tumor promotion effects of OA relate to p53 tumor supressor function (or dysfunction) remain unclear. Rat embryonic fibroblasts harboring a temperature-sensitive mouse p53 transgene were treated with 50 nM doses of OA. At the wild-type permissive temperature this treatment resulted in: (i) the hyperphosphorylation of sites within tryptic peptides of the transactivation domain of p53; (ii) an increase in p53 affinity for a p21(waf1) promotor oligonucleotide; (iii) an increase in cellular steady state levels of p21(waf1) message; (iv) a G2/M cell cycle blockage in addition to the G1/S arrest previously associated with p53; and (v) no increased incidence of apoptosis. On the other hand, OA treatment at the mutated p53 permissive temperature resulted in a relatively high incidence of aberrant mitosis with no upregulation of p21(waf1) message. These results suggest that while wild-type p53 blocks the proliferative effects of OA through p21(waf1)-mediated growth arrest, cells with non-functional p53 cannot arrest and suffer relatively high levels of OA-mediated aberrant mitoses.

Animals↗
PubMed1999

Cup feeding: an alternative to bottle feeding in a neonatal intensive care unit.

Cup feeding has been suggested as an alternative to bottle feeding to help promote breastfeeding by avoiding nipple confusion. To demonstrate the possibility and utility of cup feeding, records of 59 preterm and low birthweight babies (born before 37 weeks' gestation) admitted to a neonatal intensive care unit (NICU) from May 1995 to April 1996 were analyzed. Feeding was initiated on cup if swallowing was present and cup feeding was possible as early as 29 weeks' gestational age with a birthweight of 900 g. In the case of five infants (38 per cent) in the gestational age group 28-30 weeks, 19 infants (52 per cent) in the 31-34 weeks' gestation group, and six (56 per cent) in the 35-37 weeks' gestation group, feeding could be commenced directly with a cup. Out of 59 infants, 33 infants (56 per cent) could be discharged on exclusive breastfeeding. It was concluded that cup feeding is a useful alternative to bottle feeding and an effective method of feeding preterm and small infants in NICU. Cup feeding allows successful breastfeeding without causing 'nipple confusion'.

Breast Feeding↗
PubMed1999

Delayed Tc-99m citrate scintigraphy in the evaluation of palpable breast masses.

The aim of this study was to evaluate the potential of Tc-99m citrate as a new tumor-localizing agent in palpable breast masses. Scintimammography was performed in 43 female patients. Of these, 10 women (group A) were considered to be healthy with no palpable breast masses, and the remaining 33 patients (group B) had palpable breast masses. All patients with palpable breast masses underwent fine-needle aspiration cytology and subsequent biopsy within 2 weeks of the study. Nine patients had a primary malignant lesion of the breast, whereas 24 patients had benign disease. The patients with breast cancer underwent surgery, and subsequently a histopathologic diagnosis was made. Sensitivity, specificity, and accuracy values obtained in our study were 87%, 100%, and 90%, respectively. Scintimammograms were performed in these patients up to 24 hours. Initial uptake at 1 and 3 hours was noted in all the breast masses. However, benign masses did not show persistence of tracer uptake at 24 hours, whereas those that were malignant continued to show persistent radionuclide concentration. Thus, the uptake and outflow pattern seemed to differentiate benign breast disease from breast cancer. The study shows the potential of Tc-99m citrate for imaging and evaluating breast masses.

Adolescent↗
PubMed1999

Cyanoacrylate tissue adhesive augmented tenoplasty: a new surgical procedure for bilateral severe chemical eye burns.

PURPOSE: To report on cyanoacrylate tissue adhesive augmented tenoplasty, a new surgical procedure for bilateral severe chemical eye injuries. METHODS: A 26-year-old man presented with bilateral severe (grade IV) chemical burns involving the eye, periorbital tissues, face, and neck. Despite adequate medical therapy, corneal, limbal, and scleral ulceration progressed in both eyes. Secondary Pseudomonas keratitis necessitated therapeutic penetrating keratoplasty in the right eye. Tenoplasty and glued-on rigid gas permeable contact lens were unsuccessful to arrest progression of corneolimboscleral ulceration in the left eye. We applied n-butyl cyanoacrylate tissue adhesive directly on the ulcerating corneal, limbal, and scleral surface to augment tenoplasty. RESULTS: The left ocular surface healed with resultant massive fibrous tissue proliferation and symblepharon on the nasal side. Ocular surface rehabilitation resulted in a vascularized leukomatous corneal opacity with upper temporal clear cornea. The patient achieved visual acuity of 6/36 in the left eye. CONCLUSION: We suggest that cyanoacrylate tissue adhesive-augmented tenoplasty can be undertaken to preserve ocular integrity and retain visual potential in a severe chemical eye injury.

Adult↗
PubMed1999

Immunological defect in leprosy patients: altered T-lymphocyte signals.

The early events of activation were studied in paucibacillary (TT/BT) and multibacillary (BL/LL) leprosy patients by stimulation of their lymphocytes with mitogenic agents (calcium ionophore A23187/PMA) and Micobacterium leprae antigen (PGL-1). Maximum proliferation in response to PMA/A23187 and PGL-1 was observed in the BT/TT patients and the control group, respectively. Inositol triphosphate (IP3) and calcium were constitutively elevated in BT/TT and LL/BL patients. PMA/A23187 caused an increase in both IP3 and [Ca2+]i in BT/TT patients and controls. PGL-1 marginally increased IP3 levels in BT/TT patients. In the LL/BL patients, although PMA/A23187 increased IP3 levels, but no change was seen in [Ca2+]i, PGL-1 had no effect. Protein kinase C levels were seen to be associated with particulate fractions in BT/TT patients and were found to increase further in response to PMA/A23187. PGL-1 did not increase translocation of protein kinase C in controls or LL/BL patients. A preactivated and sensitised state of T-lymphocytes was observed in BT/TT patients, responsive to antigen and mitogens, whereas the cells of LL/BL patients were unresponsive to PGL-1. The altered signal transduction events characterised in the MB patients thus correlate well with the anergic state of their cells.

Calcium↗