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Biomedical subjects

N M Gupta

Publications and source records attributed to N M Gupta.

At least 19 recordsLinked to original sources
PubMed2006

P53, COX-2, iNOS protein expression changes and their relationship with anti-oxidant enzymes in surgically and multi-modality treated esophageal carcinoma patients.

Esophageal carcinoma has a high incidence in India but its etiology remains unknown. In the present study the correlation between apoptosis regulatory proteins and anti-oxidant enzymes in 40 esophageal carcinoma patients was examined. Patients in one group were operated by transhiatal esophagectomy and in the second group were administered cisplatin (30 mg/m2/day) and 5-fluorouracil (5-FU) (750 mg/m2/day) daily for three days followed by surgery after four weeks of neo-adjuvant therapy (NAT). Complete pathological response was achieved in 15% of patients. Results obtained by Western blot analysis showed over-expressed p53 and COX-2 protein levels in the tumor tissues as compared to the adjoining tissue and its paired normal mucosa in both groups of patients. Immunohistochemical studies showed heterogenous p53 staining pattern with sections showing both nuclear and cytoplasmic staining with 36.8% mild, 10.5% moderate and 52.6% intense p53 immunoreactivity. Both COX-2 and iNOS immunostaining revealed 25% negative and 75% mild to strongly positive immunoreactivity. Correlation studies demonstrated a positive relationship between p53 and COX-2 (P=0.030; r = +0.70) in surgically treated patients. The association of COX-2 and p53 with various anti-oxidant enzymes showed a significantly positive correlation between COX-2 expression and catalase activity and an inverse correlation between p53 expression and superoxide dismutase and catalase activity in the tumor tissue of patients given NAT. In addition, we observed a negative trend between p53 expression levels and GPx enzyme levels in both the adjoining and tumor tissue of patients having undergone surgery as main mode of treatment.

Adenocarcinoma↗
PubMed2005

Vapor-phase photo-oxidation of methanol over nanosize titanium dioxide clusters dispersed in MCM-41 host material part 1: synthesis and characterization.

Nanosize clusters of titania were dispersed in mesoporous MCM-41 silica matrix with the help of the incipient wet-impregnation route, using an isopropanol solution of titanium isopropoxide as precursor. The clusters thus formed were of pure anatase phase and their size depended upon the titania loading. In the case of low (< 15 wt %) loadings, the TiO2 particles were X-ray and laser-Raman amorphous, confirming very high dispersion. These particles were mostly of < or = 2 nm size. On the other hand, larger size clusters (2-15 nm) were present in a sample with a higher loading of approximately 21 wt %. These particles of titania, irrespective of their size, exhibited an absorbance behavior similar to that of bulk TiO2. Powder X-ray diffraction, N2-adsorption and transmission electron microscopy results showed that while smaller size particles were confined mostly inside the pore system, the larger size particles occupied the external surface of the host matrix. At the same time, the structural integrity of the host was maintained even though some deformation in the pore system was noticed in the case of the sample having highest loading. The core level X-ray photoelectron spectroscopy results revealed a + 4 valence state of Ti in all the samples. A positive binding energy shift and the increase of the width of Ti 2p peaks were observed, however, with the decrease in the particle size of supported titania crystallites, indicative of a microenvironment for surface sites that is different from that of the bulk.

Crystallization↗
PubMed2005

Vapor-phase photo-oxidation of methanol over nano-size titanium dioxide clusters dispersed in MCM-41 host material part 2: catalytic properties and surface transient species.

We report in this paper on the ultraviolet-assisted vapor-phase oxidation of methanol at room temperature, with the help of nano-size clusters of titanium dioxide dispersed in an MCM-41 silicate matrix. The surface species formed during the adsorption/oxidation of methanol and the transformation that they undergo as a result of ultraviolet irradiation were monitored using in-situ Fourier transform infrared and thermal desorption spectroscopy techniques. Parallel experiments conducted on TiO2/MCM, bulk titania, and pristine MCM-41 samples helped in identifying the individual role of titanium dioxide and host matrix in these processes. The photo-catalytic oxidation of methanol, at concentrations of 0.1 to 1.1 mol% in air, gave rise to formation of CO2 and H2O as products, for both the TiO2/MCM and bulk TiO2 samples. No such reaction occurred on titania-free MCM. Furthermore, the rate of reaction depended upon the TiO2 content of a sample and also on the concentration of methanol in reaction mixture. Thus, the rate of conversion increased progressively with the increase in TiO2 loading from 5 to 21 wt% in TiO2/MCM samples, particularly for the experiments with high concentration of methanol. For low methanol concentration (0.1 mol%) in air, the effect of titania content in MCM was very small. The specific activity (per g of titania) of a sample, on the other hand, showed an inverse relationship with the loading of titanium dioxide in a sample. Infrared and temperature-programmed desorption results revealed that the mode of CH3OH adsorption and the reactivity of the transient species formed during the oxidation process were independent of the size of dispersed titania particles. Thus, the particles of approximately 2-6 nm size, present in TiO2/MCM, exhibited a chemisorption behavior similar to that of the bulk titania. The results of the present study provide strong evidence that the hydroxyl groups, both on the host matrix and at the titania sites, participate independently in the formation of methoxyl groups and at the same time promote the heterogeneous photo-catalytic oxidation of methanol molecules via formation of transient formate groups. Our results also show that the effect of titania crystallite size in the photo-catalytic properties relate mainly to the larger surface area and hence to the enhanced number of chemisorption sites, rather than to the changes in electronic properties.

Catalysis↗
PubMed2003

Xanthogranulomatous cholecystitis.

Twelve cases of xanthogranulomatous cholecystitis are reported. The clinical presentation was similar to chronic cholecystitis. All patients had associated gallstones. The diagnosis was achieved at histopathological examination of the resected gall bladders and none had any focus of malignancy. Cholecystectomy was curative.

Adult↗
PubMed2001

Comparison of the clinical profile and outcome for squamous cell carcinoma and adenocarcinoma of the distal esophagus and cardia in India.

This retrospective review aimed to assess the clinical profile and outcome of squamous cell carcinoma as compared with adenocarcinoma of the lower third of esophagus and cardia following a transhiatal esophagectomy. A total of 169 patients were analyzed retrospectively in this series from 1989 to 1994. There were 100 patients with squamous cell carcinoma (SCC) and 69 patients with adenocarcinoma (ADC). All tumors were assessed by an esophagogram, upper gastrointestinal endoscopy, and abdominal ultrasonography. The surgical procedure performed in all cases was a transhiatal esophagectomy (THE). The mean age of the patients with SCC and ADC was comparable (48 +/- 14 vs 54 +/- 12 years). Male/female ratio was 1.0:1.4 in the SCC group while in the ADC group it was 8.8:1.0. The main symptom in both the groups was grade II dysphagia (62% in SCC and 60% in ADC). The mean length of the tumor was 6.6 +/- 4.5 cm in the SCC group and 4.2 +/- 3.3 cm in the ADC group. The resectability rate of the SCC group was significantly higher (76%) than in the ADC group (55%). The 6-month and 1-year survival for the SCC patients was not significantly different from the ADC patients (83.7% and 49.3% vs 85.0% and 54.0%). The 5-year survival achieved in SCC was higher than in the ADC group (11.6% vs 7.2%) but the difference was not statistically significant. Adenocarcinoma arising from the distal esophagus and cardia was more common in males, and also occurred in a higher age group and had a lower resectability rate than squamous cell carcinoma. No case of Barrett's esophagus was encountered. The short- and long-term survival in both tumors were similar.

Adenocarcinoma↗
PubMed2001

Minimizing cervical esophageal anastomotic complications by a modified technique.

BACKGROUND: The anastomotic leak and stricture formation after esophagectomy and cervical esophagogastric anastomosis deny patients with esophageal carcinoma the benefits of surgery. The present study was designed to ascertain whether a wide cross-sectional area at the site of anastomosis leads to lesser anastomotic complications. METHODS: One hundred patients with resectable carcinoma of the esophagus were randomly distributed into two groups of 50 each. All patients underwent one-stage transhiatal esophagectomy. In group A, 3 x 2 cm gastric crescent was excised from the anterior wall of the gastric tube before constructing the cervical esophagogastric anastomosis. No such intervention was done in group B, which acted as control. All patients were followed up for at least 3 months for detection of anastomotic complications. RESULTS: The incidence of anastomotic leak in the study group was significantly less in comparison with the control group (4.3% versus 20.8%; P = 0.03). Similarly, anastomotic stricture formation was significantly lower in the study group (8.5% versus 29.2%; P = 0.02). CONCLUSIONS: A wide cross-sectional area achieved at the anastomotic site by removal of gastric crescent resulted in significantly lower anastomotic complications.

Adolescent↗
PubMed2001

Gastrointestinal stromal tumors the assessment of malignant potential.

GISTS are the largest category of non-epithelial neoplasms of stomach and small bowel. Numerous immunohistochemical, ultrastructural and flow cytometry studies have been carried out for evaluation of prognostic factors which could predict malignant behaviour of these neoplasms. Tumor size of 5 cm and mitosis of 2/10 hpf were suggested as two important parameters which could predict the chances of recurrence and clinically aggressive course. The aim of this study is to examine predictive value of these two important parameters in assigning the tumors as high, intermediate and low risk groups. Using these two parameters we categorized 30 cases of GIST over a period of 6 years (1990-95) into low, intermediate and high risk groups and examined other features of these cases. Based on these two parameters alone we found that 4 cases each in low and intermediate group could be assigned to a higher risk group clinically as there were presence of adjacent organ infiltration, lymphatic emboli, serosal nodules, lymph node metastasis and transmural infiltration. Hence, other features like hemorrhage, necrosis and anaplasia should also be included in risk assessment. Metaplastic tissues like bone, cartilage and adipose tissues were seen only in high-risk categories.

Adolescent↗
PubMed2000

Endoscopic dilation for treatment of anastomotic leaks following transhiatal esophagectomy.

BACKGROUND AND STUDY AIMS: Anastomotic leak is a known complication after transhiatal esophagectomy (THE) and cervical esophagogastric anastomosis. Conservative management takes a long time to heal such leaks. We assessed the role of endoscopic dilation in patients with anastomotic leak following THE. PATIENTS AND METHODS: Eight consecutive patients (seven men, one woman; mean age 51) with anastomotic leak following THE were subjected to endoscopic dilation using Savary Gilliard dilators of 7-15 mm diameter. The mean interval between surgery and detection of leak was 9 days (range 5-22 days) and dilation was performed at a mean interval of 11.4 days (range 1-20 days) after detection of the leak. RESULTS: Drainage from fistulas stopped completely after 1-8 days (mean 3 days). X-ray with water soluble contrast showed closure of the fistula in all cases. Duration of follow-up ranged from 2 to 12 months. Anastomotic strictures developed in three patients. These patients required three sessions each of repeat dilation, and were alive at follow-up periods of 2, 4, and 12 months, respectively. One patient developed recurrence of growth at an anastomotic site. Four patients died because of distant metastasis. CONCLUSIONS: Bougie dilation of anastomotic sites is a safe and effective technique for the healing of anastomotic leaks following THE. However there is a need for a prospective randomized trial comparing endoscopic dilation with no dilation in patients with anastomotic leaks following THE.

Adult↗
PubMed1999

Usefulness of percutaneous transhepatic biliary drainage in patients with surgical jaundice--a prospective randomised study.

BACKGROUND: Patients with obstructive jaundice undergoing surgical procedures have a significant risk of morbidity and mortality. The role of preoperative percutaneous transhepatic biliary drainage (PTBD) was evaluated in a randomized trial. METHODS: A total of 40 patients were assigned to either preoperative PTBD (n = 20), or surgery alone (n = 20). PTBD was performed under ultrasound guidance. There were no major complications related to the procedure. RESULTS: Ultrasound guided drainage was a successful and safe method of preoperative biliary decompression. There was a marked relief from pruritus and significant reduction of hyperbilirubinaemia from a mean of 386.48 mumol/L to 116.10 mumol/L (p < 0.001). Mean duration of drainage was 42.5 days. Postoperative complications occurred in five patients in PTBD group (25%) compared to 11 patients (55%) in the control group. One death (5%) occurred in PTBD group compared to four deaths (20%) in the control group (significant at 5% level with probability 0.2). CONCLUSIONS: Ultrasound guided drainage is a useful preoperative supportive measure in preparing deeply jaundiced patients for surgery and permits hepatic function to return to a near normal state preoperatively. The improved results in our study were due to longer duration of drainage.

Adult↗
PubMed1998

Endotoxemia predicts outcome in acute pancreatitis.

The incidence of complications of acute pancreatitis is high in patients with endotoxemia, and so we determined the endotoxin levels in the blood and peritoneal fluid of patients with acute severe pancreatitis to correlate the levels with any sequelae. Fourteen patients with acute severe pancreatitis were examined with regard to clinical features, biochemical tests, and laparotomy (n = 9). In all coagulation profiles, blood gas analysis, chest and abdominal x-rays, ultrasound, and abdominal computed tomography scan (n = 10) were performed. Qualitative estimation of endotoxin levels was done in peripheral blood and peritoneal and peripancreatic fluid. Ten (71.42%) of 14 patients had endotoxin in the blood, and 9 (64.28%) had it in the peritoneal fluid. Twelve (85.7%) had pulmonary involvement, with hypoxia being the most common (85.7%); among them endotoxin was found in the blood of 10 (83.32%) and in the peritoneal fluid of 8 (66.66%) patients. Renal dysfunction was found in 4 (28.57%) patients; endotoxin was present in the blood of all 4 patients and in the peritoneal fluid of 3 (75%) patients. Cardiovascular abnormality was detected in 8 (57.14%) patients, and endotoxin was present in the blood and peritoneal fluid of all patients. Metabolic abnormality was present in 8 (57.14%) patients; endotoxin was present in the blood of all 8 patients and in the peritoneal fluid of 7 (87.6%) patients. Eight (88.88%) of the 9 patients who required surgery had endotoxemia. Three (30%) patients with endotoxemia survived, whereas all 4 patients without endotoxemia survived. Mean hospital stay was 61.2 days and 46.7 days for endotoxin-positive and endotoxin-negative patients, respectively. We conclude that the presence of endotoxin in blood and peritoneal fluid correlates with the severity, systemic complications, and mortality rates of acute pancreatitis. Endotoxin estimation can identify patients at risk in the early stages of acute pancreatitis.

Acute Disease↗
PubMed1998

Pedunculated large leiomyoma of esophagus.

We report a patient with pedunculated esophageal leiomyoma which was 20 cm in length. Barium swallow had shown a grossly dilated esophagus with filling defect along its whole length, giving an appearance suggesting achalasia and retained food. The patient is doing well after transhiatal esophagectomy.

Esophageal Neoplasms↗
PubMed1997

Transhiatal oesophagectomy for benign obstructive conditions of the oesophagus.

BACKGROUND: Transhiatal oesophagectomy is an accepted approach for the treatment of carcinoma of the oesophagus. However, experience of this technique in benign diseases is limited. METHODS: Transhiatal oesophagectomy was done in 29 patients for benign oesophageal conditions including corrosive stricture (21), achalasia of the cardia (four), tuberculosis (one), mediastinal fibrosis (one), Crohn's disease (one) and peptic stricture (one). Dysphagia was the predominant symptom in all patients; strictures had all previously been dilated repeatedly. The stomach was used as an oesophageal substitute in 24 patients; in five with a scarred stomach due to damage by a corrosive agent, oesophagocoloplasty was performed. Resection and reconstruction were done in one stage in 25 patients; four with poor nutritional status had a two-stage procedure. RESULTS: There was no perioperative death. Complications encountered were recurrent laryngeal nerve palsy (six patients) which was mostly transient, anastomotic leak (seven) and stenosis (eight). Postoperative function of the intrathoracic stomach was satisfactory. CONCLUSION: Transhiatal oesophagectomy is a safe and satisfactory procedure for benign obstructive conditions of the oesophagus.

Adolescent↗
PubMed1997

Primary gastrointestinal lymphoma--disease spectrum and management: a 15-year review from north India.

OBJECTIVE: To analyze retrospectively the disease spectrum and outcome of primary gastrointestinal lymphoma (PGIL) in a tertiary referral center in north India. MATERIAL: Seventy five patients presenting with PGIL between January 1971 and December 1985 were evaluated. RESULTS: The 49 males and 26 females were aged 3.5-69 years (mean 34) at presentation. Abdominal pain, weight loss and vomiting were cardinal symptoms at presentation; the stomach was the most common site of involvement. Histologically, a majority of patients were classified as having diffuse poorly-differentiated lymphocytic lymphoma (46.7%) and diffuse histiocytic type (30.7%). Twenty seven (36%) patients had stage I disease, 31 (40%) stage II, 11 (14.7%) stage III, and 6 (8%) stage IV. At laparotomy, primary resection and anastomosis was carried out in 66 patients, while only biopsies were taken in nine. Forty eight patients received adjuvant radiation with or without chemotherapy. The mean follow-up was 3.9 years (range 1-14). The 5-year actuarial survival was 34%, 25% and 16% for stages I, II, and higher-stage disease, respectively. The survival was significantly better (p < 0.01) for gastric location (44%) compared to other sites (24%). CONCLUSION: PGIL was more common in the 3rd and 4th decades of life, with the stomach being the predominant site of involvement. Survival was better among patients with stages I and II disease, and gastric location of lesion.

Adolescent↗
PubMed1996

Emergency transhiatal oesophagectomy for instrumental perforation of an obstructed thoracic oesophagus.

Between 1986 and 1994, 14 patients underwent emergency transhiatal oesophagectomy for iatrogenic instrumental perforation of the oesophagus. Continuity of the alimentary tract was restored immediately with cervical anastomosis by oesophagogastroplasty in 13 and oesophagocoloplasty in one. Six patients had oesophageal perforation with a carcinoma, seven had corrosive strictures, and cardiac achalasia was present in one. Only five patients underwent operation within 24 h of initial trauma. There were two postoperative deaths. Resectional surgery, though aggressive, has given good results for perforations with oesophageal strictures. Transhiatal subtotal oesophagectomy has both theoretical and practical advantages over transthoracic resection in the management of instrumental perforation with a distal stricture.

Adolescent↗