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Biomedical subjects

A Shah

Publications and source records attributed to A Shah.

At least 289 records · Page 16Linked to original sources

Lymphangiomatosis. Histologic and immunohistochemical analysis of four cases.

Lymphangiomatosis is a rare condition that involves bone, soft tissue, or viscera in a diffuse fashion. We report four examples affecting male infants and boys (aged 9 months to 11 years: mean, 5.3 years). All four cases presented with respiratory symptoms. Investigations showed chylothorax in all patients and chylopericardium in one patient. Three patients showed multiple lytic lesions in several bones on the x-rays. Imaging studies of lungs and spleen suggested lymphangiomatosis. Biopsy specimens of the parietal pleura, lung, skin, or bone revealed an increase in the size and number of thin-walled channels lined by attenuated endothelial lining. All had histological evidence of parietal pleural involvement. In addition, lung involvement was seen in three cases and skin involvement in two cases. Factor VIII-related antigen and CD31 were the most reliable immunocytochemical markers in highlighting the endothelia. All the patients had repeated thoracocentesis and pleurodesis to control chylothorax; three died within 6 to 33 months of presentation (mean, 15 months). Autopsy performed in two cases revealed additional involvement of spleen, bone, and mediastinum. Further, lymphangiectasia was seen in the liver, kidney, tests, lymph node, intestines, and adrenals.

Biopsy↗

Relationship between cell-cycle state of erythroid progenitors and fetal hemoglobin synthesis.

DNA-synthesis state of circulating burst forming unit-erythroid (BFU-E) was evaluated in patients with sickle cell anemia and correlated with percent of fetal hemoglobin synthesized in the BFU-E-derived cells. Percentage of S-phase BFU-E inversely correlated with percent fetal hemoglobin synthesized in the BFU-E-derived cells (simple linear correlation coefficient, r = -0.8, P = 0.0302; polynomial regression, R = -0.99, P = 0.0002). This observation is of relevance to our understanding of the relationship between the developmental stage of the erythroid progenitors and expression of globin genes.

Cell Cycle↗

Ito cell expression of a nuclear retinoic acid receptor.

Although it has been suggested that retinoids regulate Ito cell proliferation and collagen synthesis, little is known about the ability of Ito cells to respond to retinoids in vivo. Because retinoids may mediate their molecular effects through nuclear receptors, Ito cells were examined for the presence of one of these receptors, nuclear retinoic acid receptor-beta. The modulation of nuclear retinoic acid receptor-beta expression was also studied during cell culture and hepatic fibrogenesis. Northern hybridization analysis revealed that Ito cells freshly isolated from normal rat liver contained nuclear retinoic acid receptor-beta messenger RNA at levels significantly higher than those found in other hepatic cell types. Ito cells also contained messenger RNA for two other nuclear retinoic acid receptors, nuclear retinoic acid receptor-alpha and nuclear retinoic acid receptor-gamma. Using an antibody to human nuclear retinoic acid receptor-beta, the nuclear presence of this receptor was demonstrated in normal Ito cells. In contrast, Ito cells cultured for at least 7 days had no detectable messenger RNA or nuclear staining for nuclear retinoic acid receptor-beta despite a 20 +/- 5-fold increase in the messenger RNA level of another retinoid binding protein, cellular retinol binding protein. Analysis of Ito cells isolated from rats with carbon tetrachloride-induced hepatic fibrosis revealed an 81% +/- 3% decrease in nuclear retinoic acid receptor-beta messenger RNA levels in these cells when compared with normal Ito cells. No difference in the messenger RNA levels of cellular retinol binding protein was found in Ito cells isolated from either normal or fibrotic liver.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

CT in childhood allergic bronchopulmonary aspergillosis.

CT of the thorax done during acute severe asthma in two paediatric patients demonstrated central bronchiectasis, a sine qua non for the diagnosis of allergic bronchopulmonary aspergillosis. Bronchography, regarded as the gold standard, was done subsequently on recovery. A comparative segmental analysis revealed that CT was able to identify immediately 24 of 27 segments which showed central bronchiectasis on bronchography. Early diagnosis with the aid of CT enabled immediate intervention which may have helped to prevent further lung damage in the paediatric patients.

Aspergillosis, Allergic Bronchopulmonary↗

Initial experience with therasonic lithotriptor.

Piezoelectric shock wave lithotripsy has been shown to offer a low-cost, safe, anesthesia-free yet effective means of disintegrating urinary calculi. The Therasonic lithotriptor combines proprietary piezoelectric shock wave technology for effective stone fragmentation with a multi-purpose urologic table and both fluoroscopic and ultrasound imaging for accurate stone localization and real-time treatment monitoring. From December 1, 1988 to November 15, 1989, 138 patients with 172 calculi were treated (94.2% were intrarenal, 5.8% were in ureter). All stones greater than or equal to 4 mm were considered suitable for treatment. Lithotripsy was performed under intravenous sedation except when ancillary procedures were necessary. For evaluation of device effectiveness, 94 patients were available with follow-up greater than or equal to thirty days. Successful fragmentation (stone free or residual debris less than or equal to 4 mm) was achieved in 97 percent of patients. The retreatment rate for stones 0.5-2.0 cm was 11 percent, and the overall retreatment rate was 21.2 percent regardless of stone size. Complications were minimal, transient, and resolved spontaneously.

Adult↗

The effects of hepatic fibrosis on Ito cell gene expression.

While Ito cells appear to be a major source of increased matrix synthesis during hepatic fibrogenesis, the cellular changes that occur in these cells during liver fibrosis have not been well delineated. In this study we examined Ito cell gene expression in isolated cells from normal rats, and rats with carbon tetrachloride-induced fibrosis, in order to better define the changes occurring in these cells during this pathologic process. Specifically, we addressed three questions: (1) which matrix genes are over expressed in Ito cells in fibrotic liver; (2) do these cells increase their expression of the fibrogenic cytokine transforming growth factor-beta 1 (TGF-beta 1); and (3) do Ito cells change their phenotype during hepatic fibrogenesis as reflected by alterations in the expression of their intermediate filament genes? Northern hybridization analysis revealed that Ito cells isolated from fibrotic livers had significant increases in mRNA levels of types I, III and IV procollagen compared to normal cells, while no increases were found in hepatocytes, and Kupffer/endothelial cells had only an increase in type I procollagen mRNA. Analysis of other matrix proteins which increase during hepatic fibrogenesis revealed elevations in laminin B and fibronectin mRNA levels only in Ito cells. Increased Ito cell matrix gene expression was also associated with a 4-fold increase in TGF-beta 1 levels in these cells. No increase in TGF-beta 1 mRNA was found in hepatocytes, and less than a 2-fold increase was found in Kupffer/endothelial cells isolated from fibrotic livers.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Legionnaires' disease and acute renal failure: case report and review.

The case of a 26-year-old man with pneumonia due to Legionella pneumophila associated with acute renal failure is presented, and the English-language literature on legionnaires' disease is reviewed. For this review, acute renal failure was defined as rapid deterioration in renal function indicated by a rise in levels of blood urea nitrogen and creatinine with or without the presence of oliguria. Our patient experienced renal failure and underwent hemodialysis. His condition gradually improved after treatment of legionnaires' disease with erythromycin. Biopsy of the kidney showed acute tubulointerstitial nephritis. Immunofluorescence microscopy demonstrated the presence of L. pneumophila serogroup 1. The laboratory findings suggested rhabdomyolysis. To our knowledge, this is the first case report of a patient with legionnaires' disease who recovered from acute renal failure and in whom the presence of L. pneumophila was demonstrated, and we believe it is the first case in which morphology of the kidney demonstrated the presence of L. pneumophila in a patient with legionnaires' disease, rhabdomyolysis, and renal failure.

Acute Kidney Injury↗

Systemic infusion versus bolus chemotherapy with 5-fluorouracil in measurable metastatic colorectal cancer.

From January 31, 1986 to January 31, 1989, 184 eligible patients were enrolled in a randomized study of either infusional or bolus 5-fluorouracil (5-FU) for the treatment of metastatic measurable colorectal cancer. Infusion was administered at an escalated dose schedule starting at 350 mg/m2 per day for 2 weeks with a 2-week rest period on a monthly basis, while bolus 5-FU was started at 400-450 mg/m2 for 5 days every 28 days. In these chemotherapy-naive patients with good performance status, the infusion arm produced a response in 11 of 88 patients versus 6 of 82 in the bolus arm (p = 0.384). Progression free survival was significantly longer (p = 0.0139) in the infusion group (3.8 versus 2.3 months), but no significant difference in survival was observed (p = 0.207). As expected, the toxicities of the regimens were different in character, but each had approximately a 20% incidence of significant toxicities. Neither of these methods of administering fluorouracil results in an exceptional response rate, nor does the infusion have an impact on survival as compared to the bolus route. If this type of complicated infusional approach is to continue, especially with increasing dosage (which could be accomplished on our schedule), randomized studies with survival as an endpoint must remain the gold standard.

Adult↗

Rationalizing neuroleptic polypharmacy in chronic schizophrenics: effects of changing to a single depot preparation.

This study investigated the effects of transferring patients on combined depot and oral neuroleptics to a single depot preparation; a secondary objective was to assess the effects of transferring patients from one depot neuroleptic to another. It was found that, whereas transferring from one depot preparation (flupenthixol) to another (fluphenazine) had no clear disadvantage for the patients, changing over from a combined oral and depot (fluphenazine) regimen to equivalent doses of depot alone resulted in an unacceptably high rate of relapse. The reasons for this may relate to either the unique pharmacokinetics of these drugs or subtle qualitative differences between them. It is suggested that caution is necessary whenever attempts are made to rationalize polypharmacy in schizophrenic patients.

Administration, Oral↗