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Biomedical subjects

T Ahmed

Publications and source records attributed to T Ahmed.

269 records · Page 15Linked to original sources
PubMed1979

Comparison of vector competence for West Nile virus of colonized populations of Culex tritaeniorhynchus from southern Asia and the Far East.

Seven colonized stocks of Cx. tritaeniorhynchus from different geographic areas of Southern Asia and the Far East were assayed for susceptibility to WN virus infection by membrane feeding and by intrathoracic inoculation. Infected females also were tested for their ability to transmit virus to baby mice. No geographic pattern of differential susceptibility to WN virus infection was apparent from the experiments; however, the per os ID50 of one strain from Khulna, Bangladesh was over 10-fold greater than the ID50's of stocks from Karachi, Pakistan and Sendai, Japan. No difference in susceptibility was found by parenteral inoculation of virus. Likewise, greater than or equal to 90% of infected females from all the colonies were able to transmit virus.

Animals↗
PubMed1978

Carpal tunnel syndrome with polymyalgia rheumatica.

Association of carpal tunnel syndrome with systemic diseases is well established. Carpal tunnel syndrome preceded or existed simultaneously in 5 patients with polymyalgia rheumatica. It is probably related to tenosynovitis resulting in increase in the volume of the contents of the tunnel.

Aged↗
PubMed1978

Effect of chlorinated hydrocarbons on reproductive performance of adult White Leghorn male chickens.

Two experiments of 20 and 40 weeks duration were conducted to determine the effects of feeding dieldrin or PCB (Aroclor 1254) on the reproductive performance of adult White Leghorn males. Dieldrin at the levels used (0, 25, and 50 ppm) produced no significant changes in semen volume, semen concentration, fertility, and hatchability of fertile eggs. Mortality increased with increased levels of dieldrin and appeared related to duration of exposure to the pesticide. A significant reduction (P less than .05) in feed consumption was observed at the 25 ppm level. No significant differences in body weights were observed except shortly before death when marked reductions in both feed consumption and body weight were noted. PCB at the levels used (0, 10, 20, and 40 ppm) produced no differences in fertiluty, hatchability of fertile eggs, body weights, feed consumption, or mortality. However, over a period of 40 weeks, PCB significantly (P less than .05) reduced semen volume, semen concentrations, and testes weights,

Animal Feed↗
PubMed1976

Clinical evaluation in tinidazole in amoebiasis in children.

Forty children with symptomatic intestinal amoebiasis were treated with tinidazole in a single dose of 50 mg/kg for 3 consecutive days. A cure rate of 97% was obtained. Tinidazole was tolerated well in children and proved to be a valuable new amoebicidal drug.

Bangladesh↗
PubMedDate not supplied

The effect of four different types of food on the bioavailability of cefaclor.

This randomized, open-label, balanced, five-treatment, five-period, five-sequence, single-dose and crossover pharmacokinetic study assessed the effect of different types of food on the bioavailability of cefaclor in 18 healthy male volunteers. A single dose of cefaclor, 250-mg capsule was administered at five occasions: after overnight fasting, after two vegetarian (high-fat and low-fat) diets and two non-vegetarian (high-fat and low-fat) diets. Serial blood samples were collected upto 8 h post dose. Serum cefaclor concentrations were determined by a validated HPLC method. AUC values were not significantly affected by food intake, but the T(max) was prolonged and C(max) was decreased, depending on the type of meal. The non-vegetarian diets affected the rate of absorption of cefaclor more than the vegetarian diets. The least decrease in C(max) was produced by low-fat vegetarian diet, while the maximum decrease was produced by high-fat non-vegetarian diet. The results of this study indicate that while the rate of absorption of cefaclor is significantly decreased, the extent of absorption and the rate of elimination are not significantly decreased in the presence of food. As compared to high-fat non-vegetarian diet, the time above MIC50 concentration was significantly increased by low-fat vegetarian diet. The implications of these findings for the large vegetarian Indian population are considerable.

Analysis of Variance↗
PubMedDate not supplied

Comparative effect of different types of food on the bioavailability of cefaclor extended release tablet.

This randomized, six-treatment, six-period, six sequence, single dose, crossover pharmacokinetic study assessed the effect of different types of food on the bioavailability of 500-mg cefaclor extended release tablet in 23 healthy male volunteers. A single dose of cefaclor extended release 500-mg tablet was administered at six occasions: after overnight fasting, after two vegetarian (high-fat and low-fat), two non-vegetarian (high-fat and low-fat) and rice diets. Serial blood samples were collected up to 12 h after dose. Serum cefaclor concentrations were determined by a validated HPLC method. An almost equivalent increase in both Cmax and AUC was observed with both high-fat non-vegetarian and low-fat vegetarian breakfasts. However, when MIC90 values, a pharmacodynamic end-point were compared, the low-fat vegetarian diet fared better than the high-fat non-vegetarian diet. The results obtained favor low-fat vegetarian diet (breakfast) to be taken with cefaclor extended release tablet to achieve maximum benefit in terms of clinical efficacy.

Adult↗
PubMedDate not supplied

Intravenous bolus topotecan in patients with myelodysplastic syndrome.

We treated 16 patients with myelodysplastic syndromes with 24 courses of bolus topotecan. Patients received topotecan as a daily 15 minute infusion for 5 days at 3 dose levels (4.0 mg/m2/d, 2.0 mg/m2/d or 2.5 mg/m2/d). There was one complete response and one partial response (overall response rate 12%). Toxicity included myelosuppression, diarrhea, ileus and mucositis. There were 3 treatment-related deaths. The results of this schedule of topotecan appeared to be inferior to that reported with infusional topotecan in patients with MDS.

Adult↗
PubMedDate not supplied

Prevalence of hepatitis E virus (HEV) antibody in pregnant women of Karachi.

BACKGROUND: This study was aimed at determining the prevalence of HEV in Karachi. METHODS: Prevalence of hepatitis E antibody in pregnant women was carried out in 65 pregnant women. They had history of acute viral hepatitis while 15 control pregnant women were included having no history of jaundice. RESULTS: The statistical outcome of the present study indicates prevalence of HEV as 57% in pregnant women with jaundice. Majority of the patients (85%) were from lower socio-economic strata., with mean age of 25 years. All these patients had hemoglobin less than 10 gm%. The mean ALT level in HEV positive cases was 452 IU/L over a range of 102-5328. It was also observed that HEV affected more women in the last trimester (62%) and in primigravida (67%). It was observed that it was more common in last trimester and in primigravida. Majority of the patients (85%) were from lower socio-economic strata. CONCLUSIONS: The findings of the present study proved the presence of HEV in pregnant women and confirmed that HEV is endemic in Karachi. The study confirms that it occurs in last trimester and in young adult.

Adolescent↗
PubMedDate not supplied

Hypercalcemia associated with adenocarcinoma of the rectum. A case report and review of the literature.

Hypercalcemia is a well described complication of cancer both in solid tumor and hematologic malignancies. Metastatic adenocarcinoma of the rectum has not been reported to be associated with hypercalcemia. We report a case of a patient with metastatic adenocarcinoma of the rectum to the liver with hypercalcemia. Evaluation for other causes of hypercalcemia was negative. We suggest that adenocarcinoma of the rectum can lead to the development of hypercalcemia.

Adenocarcinoma↗
PubMedDate not supplied

Bone marrow transplantation for familial hemophagocytic lymphohistiocytosis.

A one year old child diagnosed at two months as having familial hemophagocytic lymphohistiocytosis had a partial response to etoposide. He relapsed and underwent a bone marrow transplant after conditioning with etoposide 65 mg/kg, total body irradiation and cyclophosphamide 60 mg/kg X 2 doses. Post transplant sepsis ensued and the patient expired. At autopsy residual disease was noted. Familial hemophagocytic lymphohistiocytosis continues to be a fatal disorder and etoposide is the only agent known so far with any efficacy. Bone marrow transplantation probably should be attempted early in its course and may have a role in the treatment of this disease.

Bone Marrow Transplantation↗
PubMedDate not supplied

Differential effects of leukotrienes C4, D4, and E4 in the pulmonary and systemic vasculature of sheep.

We investigated the comparative direct and cyclooxygenase-mediated effects of the constituents of slow-reacting substance of anaphylaxis (SRS-A), i.e., leukotriene C4 (LTC4), leukotriene D4 (LTD4) and leukotriene E4 (LTE4) on pulmonary and systemic haemodynamics of sheep. In 20 conscious sheep, measurements of pulmonary vascular resistance (Rpv) and systemic vascular resistance (Rsv) were obtained before and after a rapid intravenous injection of LTC4 (0.1 micrograms X kg-1), LTD4 (0.1 micrograms X kg-1) and LTE4 (1 microgram X kg-1). The same protocol was carried out after pretreatment with the leukotriene antagonist FPL-57231 or the cyclooxygenase inhibitor indomethacin. LTD4 increased mean Rpv to 421% of baseline (p less than 0.001) and had a biphasic effect on mean Rsv, which, following an initial decrease of 18% (p less than 0.05), increased to 143% of baseline (p less than 0.05). LTC4 and LTE4 had no significant effects on Rpv, while they increased mean Rsv to 144% and 143% of baseline, respectively (p less than 0.05). This effect was not preceded by a decrease in Rsv. FPL-57231 completely blocked the effects of LTC4, LTD4 and LTE4 on Rsv, and of LTD4 on Rpv. Indomethacin had no effect on LTC4, LTD4 and LTE4-induced increases in mean Rsv, while it prevented the LTD4-induced initial decrease in mean Rsv. Indomethacin also prevented the LTD4-induced increase in Rpv. A dose-response curve (0.05, 0.1, 0.5 and 1 microgram X kg-1) demonstrated that in raising Rsv, LTE4 was approximately 10 times less potent than LTC4 and LTD4.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Modification of hypoxic pulmonary vasoconstriction by aerosolized cromolyn sodium.

We have previously demonstrated the role of mast cell degranulation in the mediation of hypoxic pulmonary vasoconstriction, and its prevention by intravenous cromolyn sodium. In the present investigation, we studied the modification of the hypoxic pulmonary vascular response by aerosolized cromolyn sodium. In seven conscious sheep on two separate days, pulmonary arterial pressure, pulmonary arterial wedge pressure and cardiac output were measured for the calculation of pulmonary vascular resistance (Rpv) along with arterial oxygen tension (Pao2) during room air breathing and breathing a hypoxic gas mixture (13% O2-87% N2), without and with cromolyn sodium administration. Cromolyn sodium (20 mg X kg-1) was administered as an aerosol before and during 13% O2 breathing. The sheep had comparable degrees of hypoxia during low oxygen breathing on both days (mean PaO2: 43 and 46 mmHg). Breathing hypoxic gas mixture caused pulmonary vasoconstriction, with increases in mean Rpv of 89% (p less than 0.05). Aerosolized cromolyn sodium blunted the hypoxic pulmonary vascular response; mean Rpv increased by 27% (p less than 0.05), which was significantly different from the increase during hypoxia without cromolyn sodium treatment (p less than 0.05). We conclude that aerosolized cromolyn sodium (a mast cell membrane stabilizing agent) modifies hypoxic pulmonary vasoconstriction; however, unlike the intravenous form, aerosolized cromolyn sodium (at the dosage used) offers a partial protection.

Aerosols↗
PubMedDate not supplied

An appraisal of the efficacy of bleomycin in epidermoid carcinoma of the penis.

Since 1975 ten patients with advanced bidimensionally measurable epidermoid carcinoma of the penis were treated prospectively with bleomycin as a single agent. In addition, data of four patients with penile cancer treated at Memorial Hospital in 1971-72 as part of a drug-oriented prospective Phase I-II trial of bleomycin are included. Each patient had a complete evaluation including measurement of all measurable lesions by two independent observers. Standard response criteria were used. Bleomycin was given in doses of 3-20 mg/m2/day in a continuous infusion to 8 men and as a daily or weekly bolus in doses of 10-30 mg/m2 to six men. The median age of the patients was 54 years and median KPS 50%. Six patients had previously received two or more chemotherapeutic agents. All patients had Stage III-IV disease. Three (21%) of 14 patients responded including one patient who achieved a complete remission in the primary penile lesion and in malignant inguinal lymphadenopathy. Tumor regression was noted to start rapidly, i.e. within 2 weeks of starting protocol, but the duration of remission was short - median 3 months. The most frequent toxicity was mucositis which occurred in 8 cases. Three patients had a drug-related fever, two a drug rash and 2 had evidence of pulmonary toxicity. There was one instance each of an elevation of tests of liver function, and of alopecia. Within the context of this study, bleomycin has modest activity and moderately severe toxicity in patients with advanced penile carcinoma.

Adult↗
PubMedDate not supplied

Phase II trial of 10-deazaaminopterin for advanced hypernephroma.

10-Deazaaminopterin, a derivative of aminopterin with enhanced cellular uptake relative to methotrexate, was given to fourteen patients with advanced measurable hypernephroma. The dose-limiting toxicity was mucositis. Abnormalities in liver function were seen in 8 patients. No responses were seen in 13 adequately treated patients including 10 who had received no prior chemotherapy. The unique transport of this new group of compounds is discussed.

Adult↗
PubMedDate not supplied

Peripheral airway function in antigen-induced bronchoconstriction.

The density dependence of the maximum expiratory flow-volume curve, functional residual capacity (FRC) and specific airway conductance (SGaw) were studied in 16 asymptomatic subjects with ragweed hypersensitivity and a history of bronchial asthma, before and during bronchial provocation with ragweed extract (dose-response curve), and following inhalation of isoetharine. In ten of these subjects (seven "reactors" and three "non-reactors"), the baseline volume of isoflow (VisoV) was found to be greater than 20% of forced vital capacity. During antigen challenge, VisoV increased in all subjects; ten of these showed a greater than 35% decrease in SGaw (mean 45%) while the remaining six showed a decrease in SGaw of less than 20% (mean 9%), suggesting central and peripheral airway constriction in the former ("reactors") and primarily peripheral airway constriction in the latter ("non-reactors"). The beta-adrenergic agonist isoetharine increased SGaw and decreased VisoV, suggesting dilation of both central and peripheral airways. We conclude that in asymptomatic subjects with asthma and ragweed hypersensitivity a) peripheral airway dysfunction is frequently present, b) during antigen challenge VisoV may be a more sensitive indicator of airway response than SGaw, and c) the beta-adrenergic agonist isoetharine exhibits its bronchodilator effect in both central and peripheral airways following antigen challenge.

Adult↗