PubMed Health⌕ Search

Biomedical subjects

I A Shah

Publications and source records attributed to I A Shah.

At least 19 recordsLinked to original sources
PubMed1999

The efficacy and safety of argon plasma coagulation therapy in Barrett's esophagus.

BACKGROUND: Thermoablation is being used to eliminate the metaplastic epithelium of Barrett's esophagus and allow its reversal into squamous epithelium in an acid-controlled environment. This study assessed the efficacy and safety of a new thermoablation technique, argon plasma coagulation. METHODS: Patients with circumferential Barrett's esophagus 2 to 5 cm long were enrolled. Acid suppression was accomplished with lansoprazole. One-half the circumference of Barrett's mucosa was treated with argon plasma coagulation, and the other half served as an internal control. After macroscopic squamous re-epithelialization occurred, biopsy specimens were obtained from both areas systematically. RESULTS: Nine patients, all men with a mean age of 51.1 years, completed the study. During 24-hour esophageal pH monitoring a pH less than 4 occurred on average 2.8% of the time with a mean dose of lansoprazole of 70 mg/day. Squamous re-epithelialization developed in treated areas in all 9 patients. Biopsy showed that 7 of 9 patients (77.8%) had squamous re-epithelialization without intestinal metaplasia. Biopsy showed that 2 of 9 patients (22.2%) had squamous re-epithelialization with evidence of underlying intestinal metaplasia. There were no serious complications. CONCLUSIONS: Argon plasma coagulation in an acid-controlled environment was both efficacious and safe in the treatment of Barrett's esophagus. However, the reappearance of squamous epithelium after therapy did not exclude the presence of underlying intestinal metaplasia.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1999

Pseudomesotheliomatous carcinoma involving pleura and peritoneum: A clinicopathologic and immunohistochemical study of three cases.

Pseudomesotheliomatous carcinoma is a rare variant of peripheral adenocarcinoma of the lung that can manifest clinical, radiologic, and pathologic features similar to malignant mesothelioma. We present three patients with pseudomesotheliomatous carcinoma of the lung. In one patient the carcinoma extended beyond the thorax and extensively involved the peritoneum, mesentery, omentum, and intestines. All patients experienced weight loss and chest pain. All were white men aged 63, 65, and 67 years. Two were smokers and had shortness of breath, cough, and pleural effusion. One had a history of asbestos exposure. No patient developed dyspnea or hemoptysis. One was successfully treated for prostatic carcinoma 18 months earlier. Radiographically, all tumors were pleura-based. Grossly, the tumors spread extensively over pleural (and in one case peritoneal) surfaces and mimicked malignant mesothelioma. Histologically, all tumors were poorly differentiated and necrotic; two tumors exhibited spindle-cell components and desmoplasia. Mucin production was detectable in none, 10%, and 50% of tumor cells. The percentages of tumor cells immunoreactive for Ber-EP4 were 70%, 100%, and 80%; for Leu MI 0%, 90%, and 50%; for epithelial membrane antigen 80%, 80%, and 100%; for B 72.3%, 0%, 90%, and 20%; for polyclonal carcinoembryonic antigen 0%, 10%, and 10%; and for monoclonal 5%, 0%, and 0%. Of these, Ber-EP4 and B 72.3 rendered the most reliable diagnostic results. The clinical, radiologic, and gross and routine histologic findings were similar to those of a malignant mesothelioma; the final diagnosis could be made based mainly on immunocytochemical results. We have reviewed the English and German literature regarding 65 such tumors and present our experience with three additional cases. We emphasize the application of immunocytochemical studies on pleura-based poorly or undifferentiated malignant tumors of unknown origin.

Aged↗
PubMed1998

Papillary serous carcinoma of the peritoneum in a man: a case report.

BACKGROUND: Papillary serous carcinoma of the peritoneum (PSCP) is a rare primary peritoneal tumor, described exclusively in women. It is believed to arise from the secondary müllerian system, which is comprised of the pelvic and lower abdominal mesothelial lining and subjacent (subcoelomic) mesenchyme in women. Both mesotheliomas and PSCP arise from the coelomic epithelium, but are clinicopathologically and biologically distinct entities. METHODS: The authors report clinicopathologic findings in a man, age 74 years, who died 3 months after the diagnosis of an extensive malignant abdominal disease. RESULTS: The routine histologic and immunocytochemical studies of tumor tissue, obtained during the patient's lifetime and at autopsy, validated the unique occurrence of PSCP in a man. CONCLUSIONS: This case illustrates that PSCP can occur in a man and that this diagnosis may be considered in the differential diagnosis of papillary serous tumors of the peritoneum in male patients. Although rare, PSCP is a diagnostically distinct entity the treatment of which is similar to ovarian serous tumors rather than mesotheliomas.

Aged↗
PubMed1998

Variability of mitomycin C adsorption by activated charcoal.

A saline suspension of mitomycin C adsorbed on activated charcoal and administered intraperitoneally has been reported to be safe and effective in the treatment of gastric carcinoma. Activated charcoal specifically targets tumour and lymph-node tissues and the sustained higher local drug concentration is thought to be beneficial. The charcoal particles used in these suspensions have varied in size from > 147 microm to < 20 nm in diameter, but no data have been published to show how this might affect drug adsorption and delivery. Any variability in drug adsorption could pose a serious clinical risk for drugs with a narrow therapeutic index. We have, therefore, investigated the adsorption of mitomycin C on activated charcoal in-vitro. Activated charcoal was ground and sieved to yield four size-fractions between 180 and 53 microm. Adsorption isotherms (n > or = 3) were constructed and applied to the Freundlich model with 0-l00 microg mL(-1) mitomycin C measured by HPLC with detection at 365 nm. Adsorption of mitomycin C by activated charcoal varied by a factor of three under identical conditions at room temperature (21 degrees C) and at 37 degrees C. The specific adsorption (microg mitomycin C (mg activated charcoal)(-1)) was generally higher at 37 degrees C than at room temperature. The variability of mitomycin C adsorption was greatly reduced by addition of the surface-active agent polyvinylpyrollidone, used to determine that adsorption of mitomycin C was independent of activated charcoal particle size. The characteristics of adsorption of mitomycin C by activated charcoal are complex and should be thoroughly investigated to discover the critical controlling factors before submitting the suspensions for further clinical evaluation.

Adsorption↗
PubMed1997

Comparative immunoreactivity of CD-68 and HMB-45 in malignant melanoma, neural tumors and nevi.

The monoclonal antibody CD 68 (KP 1) reacts with fibrohistiocytic and some epithelial neoplasms; its reactivity compared with that of HMB 45 in malignant melanoma (MM) and neural tumors needs further elucidation. Using a streptavidin-biotin-immunoperoxidase procedure, we examined the reactivity of 65 MM (46 conventional, 1 polypoid, 6 desmoplastic [DMM], and 12 metastatic), 21 neurofibromas, 1 neurofibrosarcoma, 10 schwannomas, 1 perineurioma, 2 neurothekeomas, and 14 blue and 26 other nevi for CD-68, HMB-45-defined antigen, S 100 and neurofilament protein. A positive staining for CD 68 was observed in 38 of 42 primary, 5 of 6 DMM, and 11 of 12 metastatic melanomas; 6 of 10 schwannomas; 5 of 10 nevi with junctional component and all 14 blue nevi. All 21 neurofibromas, 1 each neurofibrosarcoma and perineurioma, both neurothekeomas, and all 12 nevi with dermal component were CD 68-negative. HBM 45 was expressed by all 44 primary, none of 6 DMM, and 7 of 12 metastatic melanomas; by none of 10 schwannomas, 6 neurofibromas, 1 neurofibrosarcoma, 1 perineurioma and 2 neurothekeomas. Both junctional nevi, 8 of 10 nevi with junctional components, 1 of 10 dermal components of junctional nevi, and 11 of 13 blue nevi were also HMB 45 positive. Except for 1 perineurioma, S 100 decorated all tumors examined. NF was immunoreactive in 1 of 45 conventional melanomas, 2 of 21 neurofibromas, 2 of 10 schwannomas, and 3 of 10 blue nevi; it was non-reactive in all polypoid, desmoplastic and metastatic melanomas; neurofibrosarcoma, perineurioma, neurothekeoma and other nevi. We conclude that the CD-68-reactivity in primary melanomas, neurofibromas, neurofibrosarcomas, perineuriomas, and nevi was similar to that of HMB 45. The significantly higher CD 68-positivity than of HMB 45 in metastatic and desmoplastic melanomas and schwannomas may be of diagnostic value.

Antigens, CD↗
PubMed1996

Veno-occlusive disease of the small bowel. An entity in search of identity.

Veno-occlusive disease of the bowel is a rare entity, and, to our knowledge, only two studies have been reported in the literature; these reports describe 11 patients with veno-occlusive disease of the small and large bowels. We describe a patient who developed veno-occlusive disease of the small bowel, whose histologic findings were somewhat different from those previously reported.

Adult↗
PubMed1995

Expanded programme of immunization in Karachi.

Immunization status of children and their mothers and reasons for their failure to be immunized were studied. The study lasted for two months, i.e., August and September, 1993 at the Paediatric Outpatient Department of Civil Hospital, Karachi. Three groups of patients were targeted. Six hundred and twenty-four children under 1 year of age, 955 children between the ages of 1 to 5 years and 1579 mothers were registered. These women were questioned regarding their immunization status and that of their children. In the group below 1 year of age, BCG, DPT and polio (3 doses) and measles were given to 75%, 35% and 23% respectively. Tetanus toxoid (2 doses) was given to 47% of their mothers. In the group of children between 1-5 years, BCG, DPT and polio 3 doses and measles were given to 84%, 63% and 58% respectively. Tetanus toxoid (2 doses) were given to 64% of their mothers. The main reasons for not vaccinating were lack of information and lack of motivation.

Adult↗
PubMed1993

The effects of retinoids and terbinafine on the human hepatic microsomal metabolism of cyclosporin.

Following the observation of increased trough whole blood cyclosporin A (CyA) concentrations and reduced renal function in a patient with recalcitrant generalized pustular psoriasis treated with a combination of CyA and etretinate, the effect of vitamin A analogues on human microsomal cytochrome P450-dependent CyA metabolism was investigated in vitro. In addition, the effect of terbinafine, a new allylamine antifungal agent, was also tested. Etretinate, its major metabolite acitretin, and isotretinoin, each at a single concentration of 100 microM, inhibited total hepatic microsomal CyA metabolism to a similar extent (33-45%, compared with control values). The generation of total primary and total secondary CyA metabolites was also inhibited to a similar extent by each of the retinoids. Conversely, terbinafine was without significant effect on CyA metabolism in vitro. The results, which suggest that inhibition of hepatic CyA metabolism by retinoids may contribute to increased circulating CyA concentrations, are discussed in relation to other potential drug interactions, and to the use of etretinate in reducing the CyA administered dose.

Acitretin↗
PubMed1993

Renal cell carcinoma insulated in the renal capsule with calcification and ossification.

We describe a case of renal-cell carcinoma insulated and entrapped in the renal capsule by a calcified and ossified rim. To our knowledge, this is the first time a renal-cell carcinoma of the renal capsule is reported. The fact that the tumor cells originated from the distal/medullary tubules was supported by immunohistochemical studies. The pertinent literature is reviewed.

Calcinosis↗
PubMed1993

Neurofilament immunoreactivity in Merkel-cell tumors: a differentiating feature from small-cell carcinoma.

To differentiate Merkel-cell tumor (MCT) from other neuroendocrine (NE) carcinomas, we immunostained (using avidin-biotin-peroxidase method) nine MCT and 37 NE (including 28 small-cell) carcinomas for NE markers (neuron-specific enolase and chromogranin), cytokeratin, neurofilament, vimentin, and a number of other markers. Cytokeratin was positive in 100% of MCT and in 85% of small-cell carcinomas; neurofilament and vimentin were positive in respectively 100% and 22% of MCT and 0% of NE carcinomas. Our data suggest that the coexpression of cytokeratin and neurofilament by an undifferentiated dermal or visceral tumor is of significant help in diagnosing MCT and differentiating it from small-cell carcinomas. The vimentin reactivity is a weak and insignificant discriminant.

Adult↗
PubMed1992

Influence of the distance between interrupted sutures and the tension of sutures on the healing of experimental colonic anastomoses.

Certain technical factors determine the success of the creation of intestinal anastomoses. The influence of the distance between interrupted sutures and the suture tension on wound healing was investigated in an experimental study using a specially designed suture model. The combination of a long suture distance (group A, 2.5 mm) and a short suture distance (group B, 1.5 mm) with three different suture tensions, i.e., (1) no tension; (2) moderate tension; and (3) high tension, resulted in six different techniques. Tension was created by means of a spring balance. The anastomoses were examined macroscopically, histologically by microangiography, and by bursting pressure. Apposition of the bowel wall between the interrupted sutures was inappropriate due to prolapse of the mucosa in 7.9% of the patients in group A but did not occur in groups B2 and B3. The leakage rate was 4.6% in group A and 1.3% in group B. Early healing of the mucosa was noted in group B2. Bursting pressure was significantly higher on day 2 and 4 in groups B2 and B3. The results demonstrate the influence of suture technique on the wound healing of intestinal anastomoses. The best healing pattern was achieved by a small distance between the sutures and a moderate suture tension.

Anastomosis, Surgical↗