Biomedical subjects

S Iftikhar

Publications and source records attributed to S Iftikhar.

6 recordsLinked to original sources

PubMed1999

Tension pneumothorax complicating diagnostic upper endoscopy: a case report.

Hypoxemia is common during various endoscopic procedures and may result from a variety of causes. These causes range from benign and otherwise easily reversible events like oversedation to potentially life threatening complications such as pneumothorax. Although pneumothorax has been reported secondary to gastrointestinal perforation as a complication of various therapeutic endoscopic procedures, there has been no report of pneumothorax without perforation. We report a case of a patient who developed severe hypoxemia and hemodynamic instability during diagnostic upper endoscopy as a result of pneumomediastinum and tension pneumothorax in the absence of any signs of gastrointestinal perforation and comment on various possible mechanisms. Immediate endotracheal intubation and bilateral chest tube placement resulted in prompt return of the patient's oxygenation and vital signs back to normal. This report enlarges the list of possible causes of hypoxemia during endoscopy and shows the importance of early and prompt recognition, which allowed directed therapy with a good outcome.

Aged↗

PubMed1998

Gastroparesis after celiac plexus block.

A 36-yr-old woman with metastatic mucinous cystadenocarcinoma of the pancreas underwent neurolytic celiac plexus block with 100% ethanol and 0.5% bupivacaine for intractable back pain. Several hours after the procedure she developed severe nausea and vomiting, which persisted for days despite cessation of opioid analgesics, and administration of intravenous metoclopramide and ondansetron. Both esophagogastroduodenoscopy and barium examination of the stomach and small intestine showed excess gastric fluid but no evidence of mechanical obstruction. A radionuclide study revealed delayed gastric emptying of solids. Treatment with oral cisapride 10 mg p.o. q.i.d. resulted in considerable symptomatic improvement. We document the first reported case of gastroparesis after celiac plexus block and discuss possible etiological mechanisms.

Adult↗

PubMed1996

Cytotoxic effect of beta-carotene in vitro is dependent on serum concentration and source.

In a previous study we reported that beta-carotene solubilized in tetrahydrofuran (THF) is toxic for human colonic tumor cells in vitro using media containing 10% fetal calf serum (FCS). Cytotoxicity was evident using beta-carotene concentrations that are achieved in human serum as a result of supplementation with 30 mg beta-carotene/day. In an attempt to determine the mechanism for this toxicity we investigated the effect of beta-carotene when present in human serum as a result of dietary supplementation. This effect was compared to that observed for cells incubated in THF-solubilized beta-carotene. The results indicate that human serum from subjects with a high concentration of beta-carotene is not cytotoxic. Subsequent analysis revealed that in contrast to the results using FCS, THF-solubilized beta-carotene is not cytotoxic in the presence of human serum. In addition, the effect observed with FCS is blunted with increasing FCS concentration from > or = 90% cytotoxicity using 10% FCS to 36% using 100% FCS. The difference in results obtained using FCS and human serum may be due to a serum component that is relatively lacking in FCS as compared to human serum.

Antineoplastic Agents↗

PubMed1996

In vitro beta-carotene toxicity for human colon cancer cells.

Experiments were conducted to determine the effect of beta-carotene on human colon cancer cells in vitro. beta-Carotene solubilized in tetrahydrofuran (THF) was determined to be cytotoxic for three different cell lines: LS 180, SW 620, and HCT-15. The number of LS 180 and SW 620 cells surviving treatment with 2.9 microM beta-carotene was significantly reduced relative to THF-treated cells, and a similar reduction was achieved in HCT-15 cells with use of 5.8 microM beta-carotene. These concentrations are in the range achieved in serum of individuals supplemented with beta-carotene at 30 mg/day. There was no beta-carotene cytotoxicity in the concentration range that characterizes serum of unsupplemented individuals. Vitamin E at > 200 microM was not cytotoxic and at higher concentrations slightly stimulated proliferation of all three cell lines. Exposure of cells to vitamin E did not diminish the cytotoxicity of beta-carotene, suggesting that the toxic effect of beta-carotene is not due to prooxidant activity. Percent cytotoxicity was increased by extending the duration of exposure of cells to beta-carotene. Interestingly, beta-carotene cytotoxicity decreased with increasing cell density. This density-dependent toxicity was attributable to a higher beta-carotene concentration per cell for cells plated at lower densities. Thus toxicity of beta-carotene for colon cancer cells is dose, time, and cell density dependent and occurs in vitro at concentrations that can be achieved safely in humans.

Cell Division↗

PubMed1994

Medical evaluation of the adult with HIV infection.

Early, prompt assessment and clinical management can extend the lifespan and improve the quality of life of people with HIV. The initial and subsequent medical examination should evaluate conditions most often associated with HIV infection. HIV causes multiple organ diseases, and the approach to its evaluation should be systematic and comprehensive.

Adult↗

PubMed1990

Influence of kinetin on growth, flowering and alkaloidal contents of Hyoscyamus muticus L.

Plants treated with Kinetin responded very markedly and were more bushy and darker in colour than the controls. The physical yield was maximum in the plants treated with 50 PPM followed by 100 PPM and 200 PPM. Early flowering was induced in treated plants than the controls and it was seen first in 50 PPM. Growth and flowering was not very promising in higher concentration of the Kinetin. Height measurement indicated that plants treated with the Kinetin were larger than controls throughout the observation period. This indication was prominent in 50 PPM Kinetin treated plants followed by neat higher concentrations. Chemical assay has shown that the concentration of alkaloids has increased though it is not very appreciably as compared to the physical yield of each plant. Lower concentrations have better effects both on physical yield and alkaloids percentage as compared to the higher ones. From these observations it us assumed that the use of Kinetin as plant growth regulator on Hyoscyamus muticus is economical and its further investigations may prove more useful especially on other solanaceous plants.

Journal Article↗