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Biomedical subjects

S Qureshi

Publications and source records attributed to S Qureshi.

At least 55 records · Page 3Linked to original sources

Y chromosome microdeletions and male subfertility.

Men with azoospermia and severe oligozoospermia have been investigated by molecular probing of the long arm of the Y chromosome. We find microdeletions affecting various parts of the long arm of the Y chromosome in approximately 10% of men with non-obstructive azoospermia and severe oligozoospermia but not in a fertile comparison population. This work needs further confirmation in different countries and different racial groups but it would appear that microdeletions (and presumably genetic defects) are commonly associated with defects of spermatogenesis. These findings have implications for the management of severe male subfertility with in vitro fertilization/intracytoplasmic sperm injection.

Case-Control Studies↗

Influence of anethole treatment on the tumour induced by Ehrlich ascites carcinoma cells in paw of Swiss albino mice.

The anticarcinogenic potential of anethole was studied in Ehrlich ascites tumour (EAT) in the paw of Swiss albino mice. The antitumour activity was evaluated from the cytotoxicity of EAT-cells in the paw and their biochemical changes were determined from nucleic acids, protein, malondialdehyde (MDA) and glutathione (NP-SH) concentrations. Furthermore, the observations on survival rate, tumour weight, its volume and body weight of EAT-bearing mice were made. The EAT-bearing paws were also evaluated for histopathological changes. Additional studies were undertaken on the cytological effects of anethole in order to establish its clastogenic and mitodepressive activity in normal mice. The results obtained in the present study revealed anethole to increase the survival time, reduce the tumour weight and volume and body weight of the EAT-bearing mice. It caused a significant cytotoxic effect in EAT cells in the paw, reduced the levels of nucleic acids and MDA, and increased NP-SH concentrations. The histopathological changes observed after treatment with anethole were comparable to the standard cytotoxic drug cyclophosphamide. The results on the frequency of micronuclei and the ratio of polychromatic erythrocytes to normochromatic erythrocytes showed anethole to be mitodepressive and non-clastogenic in the femoral cells of mice. Our results indicate the anticarcinogenic, cytotoxic and non=clastogenic nature of anethole. Further studies are warranted to explore the mode of action and safety of anethole for its possible use in cancer therapy.

Administration, Oral↗

Personal health benefits of Masters athletics competition.

Questionnaires (750 respondents, 44.4% response rate) examined the long-term health value of endurance exercise training in older age-classed competitors ('Masters Athletes', 551 men and 199 women) over a 7-year period (1985-1992). The majority had initially completed maximal exercise tests. The weekly time devoted to training, competition and exercise-related travel was 10 to 30 h, and the annual expenditure on clothing, equipment and entrance fees was typically in the range Canadian $500-1500. Despite their age (mean(s.d.) 58(10), current range 40-81 years), only 1.4% reported sustaining a non-fatal heart attack and 0.6% had required bypass surgery over the 7-year interval. The majority (90%) were very interested in good health; 76% considered themselves as less vulnerable to viral illnesses than their peers, and 68% regarded their quality of life as much better than that of their sedentary friends. The majority of former smokers had stopped smoking before they began training, but 37% indicated that exercise had helped them in smoking withdrawal. In keeping with their health-conscious attitude, 59% had regular medical check-ups, and 86% obeyed legislation requiring use of a seat-belt when driving. In contrast with many older people, 88% slept well or very well. Slightly over half of the sample (57%) had sustained some injury which had limited their training for one or more weeks over the 7-year study. Although participation in Masters competition appears to carry considerable health benefits, gains may in part reflect an overall healthy lifestyle.

Adult↗

Evaluation of Caralluma tuberculata pretreatment for the protection of rat gastric mucosa against toxic damage.

The ethanolic extract of Caralluma tuberculata N. E. Brown has been screened for its potential to protect gastric mucosa against the injuries caused by 80% ethanol, 0.2 M NaOH, hypertonic saline, and indomethacin. C. tuberculata at doses of 250, 500, and 1000 mg/kg body wt given 30 min before the necrotizing agents provided dose-dependent protection against the damage caused by all tested agents. The effects caused by ethanol were further investigated. Treatment of rats with 1 ml of 80% ethanol (gavage) was found to cause depletion of stomach-wall mucus, to lower the concentrations of proteins, nucleic acids, and nonprotein sulfhydryl groups in the stomach wall, and to cause histopathological lesions, including necrosis, erosions, congestion, and hemorrhage, of the stomach wall. C. tuberculata treatment caused a dose-dependent protection against all these effects. In the same manner it affected malondialdehyde concentrations altered by ethanol treatment. C. tuberculata also offered protection against mucosal damage caused by indomethacin. The protective effects of C. tuberculata in addition to its effects on mucus production and nonprotein sulfhydryl concentration may be mediated through its free radical scavenging and prostaglandin inducing properties.

Administration, Oral↗

The prognostic significance of the accumulation of p53 tumour-suppressor gene protein in gastric adenocarcinoma.

We have studied the expression of p53 in 206 patients with gastric adenocarcinomas. A standard immunohistochemical technique employing the CM-1 anti-p53 polyclonal antibody was applied to the routinely fixed and paraffin-embedded material from these tumours; overexpression of p53 was defined as positive nuclear staining: 46% (94/206) of gastric carcinomas expressed high levels of p53. There was no significant correlation between p53 positivity and the tumour grade, growth pattern, the Lauren type or lymph node metastases. Correlation with disease stage was only marginally significant (P = 0.05). Life table analysis revealed a highly significant association between p53 expression and survival (P = 0.0062), the odds ratio of death being 1.89 (95% confidence interval 1.33-2.69). The overall 5-year survival of patients with p53-positive tumours was 3% compared with 16% for those with p53-negative tumours (median survival time being 5.6 and 11.4 months respectively). These data suggest that overexpression of the p53 oncoprotein is an independent marker of shortened survival in gastric cancer patients.

Adenocarcinoma↗

Effect of Commiphora molmol (oleo-gum-resin) on the cytological and biochemical changes induced by cyclophosphamide in mice.

The anticlastogenic and biochemical potentials of Commiphora molmol were studied in Swiss albino mice treated with cyclophosphamide (CP). The C.molmol treatment (125-500 mg/kg) showed no mutagenicity. It caused a highly significant and dose-dependent mitodepressant effect in the femoral cells and reduction of RNA levels in hepatic cells as compared with the control. CP treatment showed significant increase in the frequency of micronuclei, cytotoxicity and reduction in the contents of nucleic acids and proteins. Pretreatment with C. molmol could neither alter the biochemical and cytological effects of CP nor show any additive effect of both treatments.

Animals↗

Studies on the antiinflammatory, antipyretic and analgesic activities of santonin.

Santonin, a sesquiterpene lactone, commonly found in the plants of the family Compositae was found to show significant antiinflammatory activity on acute inflammatory processes. The activity profile of santonin closely resembled that of a standard non-steroidal antiinflammatory drug, diclofenac sodium. It also showed a significant inhibitory effect on granuloma formation; however, this effect of santonin was less pronounced as compared to diclofenac sodium. Santonin caused a significant antipyretic effect in mice, which was found to be independent of the route of administration of the drug. It also increased the hot plate reaction time of treated mice, similar to morphine.

Analgesics↗

Expression of p53 protein in normal, dysplastic, and malignant gastric mucosa: an immunohistochemical study.

Mutations in the p53 nuclear oncogene are the most frequent genetic abnormalities encountered in human malignancies. Using the polyclonal antibody CM-1, we have examined the expression of the p53 oncoprotein immunohistochemically in archival material of normal, dysplastic, and malignant gastric mucosa. Abnormal expression of this protein was not observed in biopsies of normal gastric tissue (n = 30) but was detected in 22 of the 36 gastric cancers analysed (61 per cent). Nuclear staining was diffuse in 15 of the positive cancer cases, the remaining seven showing a more varied heterogeneous staining pattern. Abnormal p53 protein was not detected in mild (n = 14) or moderate (n = 16) gastric dysplasia but was present in 3 out of 15 severe dysplasia cases. The results suggest that expression of the p53 oncoprotein is a common finding in gastric cancer and occurs as a late event in the malignant transformation process.

Antibodies↗

Evaluation of the genotoxic, cytotoxic, and antitumor properties of Commiphora molmol using normal and Ehrlich ascites carcinoma cell-bearing Swiss albino mice.

The genotoxic, cytotoxic and antitumor properties of Commiphora molmol (oleo gum resin) were studied in normal and Ehrlich ascites carcinoma cell-bearing mice. In normal mice, the genotoxic and cytotoxic activity was evaluated on the bases of the frequency of micronuclei and the ratio of polychromatic to normochromatic cells in bone marrow, which was substantiated by the biochemical changes in hepatic cells. The antitumor activity of C. molmol was evaluated from the total count and viability of Ehrlich ascites carcinoma cells and their nucleic acid, protein, malondialdehyde, and elemental concentrations in addition to observations on survival and the trend of changes in body weight. The tumors at the site of injection were evaluated for histopathological changes. Treatment with C. molmol (125-500 mg/kg) showed no clastogenicity but was found to be highly cytotoxic in normal mice. The results obtained in the Ehrlich ascites carcinoma cell-bearing mice revealed the cytotoxic and antitumor activity of C. molmol which was found to be equivalent to those of the standard cytotoxic drug cyclophosphamide. On the basis of the nonmutagenic, antioxidative, and cytotoxic potential of C. molmol as observed in the present study, its use in cancer therapy seems to be appropriate and further investigations are suggested.

Animals↗

Interventional catheterization in congenital heart disease.

Balloon dilation is now an established treatment for many congenital heart defects. Recent papers deal with the extension of this approach to more complex anomalies, such as tetralogy of Fallot and transposition of the great arteries; the results are variable. Another area of investigation is balloon valvoplasty in more contentious settings, such as neonatal aortic stenosis. The catheter method appears to be as effective as surgery in these cases. Attention has also been directed to the determinants of success or failure in, for example, aortic recoarctation. Here, as in aortic stenosis, basic anatomy plays an important role. Catheter closure procedures also figure in the literature. Closure of persistent ductus now appears to be established everywhere except in the United States. Also of interest are early reports of the "button device" for closure of atrial septal defects. The use of stents appears to offer effective treatment for peripheral pulmonary stenosis, a condition with disappointing results from surgery and balloon angioplasty. Stents may also offer an alternative method for long-term maintenance of duct patency. Catheter interventions now constitute a major part of the work of pediatric cardiologists, and the present status has been summarized in the past year.

Angioplasty, Balloon↗

Ionizing radiation activates transcription of the EGR1 gene via CArG elements.

The present studies have examined the effects of ionizing radiation on control of the early growth response 1 (EGR1) gene. Exposure of human HL-525 cells to x-rays was associated with increases in EGR1 mRNA levels. Nuclear run-on assays showed that this effect is related at least in part to activation of EGR1 gene transcription. Sequences responsive to ionizing radiation-induced signals were determined by deletion analysis of the EGR1 promoter. The results demonstrate that x-ray inducibility of the EGR1 gene is conferred by a region containing six serum response or CC(A+T-rich)6GG (CArG) motifs. Further analysis confirmed that the region encompassing the three distal or upstream CArG elements is functional in the x-ray response. Moreover, this region conferred x-ray inducibility to a minimal thymidine kinase gene promoter. Taken together, these results indicate that ionizing radiation induces EGR1 transcription through CArG elements.

Base Sequence↗

Countercurrent aortography: an alternative to cardiac catheterization in infancy.

Countercurrent aortography via a peripheral artery was used to clarify the aortic arch anatomy in 25 infants in whom cross-sectional and Doppler evaluation was inconclusive. Ages ranged from 3 days to 11 months (median 9 days), and 80% were neonates. The suspected diagnosis was aortic coarctation in 21 infants, interrupted aortic arch in two, recoarctation in one, and vascular ring in one. A countercurrent aortogram provided adequate diagnostic information in 24 infants. A diagnosis of coarctation was confirmed in 15, interruption of the aortic arch in two, and vascular ring in one. In six infants countercurrent aortography excluded the presence of anomalies of the aortic arch. In only one infant, who had an anomalous origin of the right subclavian artery from the descending aorta, did this technique fail to provide adequate information. The only complication observed was transient ischemia of the arm in one patient. Countercurrent aortography is a minimally invasive procedure that can provide adequate angiographic information without the need for cardiac catheterization in patients with inconclusive echocardiographic evaluation. Injection into a right upper limb artery is preferred, because it gives better opacification of the ascending and transverse aortic arch than injection into a left one.

Aorta, Thoracic↗

A study of uric acid pretreatment for the protection of rat gastric mucosa against toxic damage.

Uric acid was evaluated for its potential to protect the gastric mucosa against the injuries caused by 80% ethanol, 0.6 m-HCl and 0.2 M-NaOH in rats. Uric acid at doses of 50, 100 or 300 mg/kg body weight provided dose-dependent protection against the ulcerogenic effects of all three agents. Other effects caused by ethanol only were studied. Serum uric acid concentrations were statistically significantly increased by both uric acid and ethanol treatments. Treatments of rats by gavage with 1 ml 80% ethanol was found to cause depletion of stomach-wall mucus, to lower the concentrations of protein, nucleic acids and non-protein sulphydryl groups in the stomach wall, and to cause histopathological lesions, including necrosis, erosions, congestion and haemorrhage, of the stomach wall. Treatment with uric acid, at doses of 50, 100 or 300 mg/kg body weight, by gavage, provided some measure of protection against all of these effects, and the protection was generally dose dependent. The protective effects of uric acid against damage to the gastric-wall mucosa may be mediated through its effects on mucus production and non-protein sulphydryl concentrations, and/or its free-radical scavenging properties.

Animals↗

Effect of Caralluma tuberculata on the cytological and biochemical changes induced by cyclophosphamide in mice.

Treatment with Caralluma tuberculata extract induced complex biochemical and cytological changes in mice. Its cytotoxicity in the bone marrow cells of mice was comparable with that of the standard drug cyclophosphamide (CP); however, unlike CP, C. tuberculata was not clastogenic (as shown by the micronucleus assay). A dose-dependent decrease in the RNA content of liver and testes was produced by C. tuberculata treatment whereas there was no effect on the content of nucleic acid and protein in the brain. In the extract-treated animals there was a significant and dose-dependent increase in the DNA content of the liver, with a negligible effect on the protein content. Combined treatment with C. tuberculata and CP showed that C. tuberculata diminished the effect of CP on DNA levels; however, RNA levels were further suppressed, resulting in increased cytotoxicity. Pretreatment with C. tuberculata extract significantly reduced the clastogenicity of CP. These results indicated the involvement of different phytoconstituents acting by different routes.

Animals↗

Effect of an acute dose of alcohol on the pharmacokinetics of oral nifedipine in humans.

Pharmacokinetic and pharmacodynamic interactions of alcohol and nifedipine were assessed in 10 healthy human volunteers. Doses of 20 mg (2 x 10-mg capsules) of nifedipine were administered with either 150 ml of orange juice or 75 ml of alcohol (94%) in 75 ml of orange juice according to a crossover randomized design. Plasma nifedipine levels were monitored for 16 hr after each dosing, along with pulse rate and blood pressure. The relative bioavailability of nifedipine, measured as AUC, was increased by 54% (533 vs 346 ng.hr/ml) after the dose of alcohol (P less than 0.0002). However, there were no significant differences between treatments in Cmax, tmax, or t1/2. Although there was no difference in the systolic and diastolic blood pressure and pulse rate between the two treatment groups, the time to reach peak heart rate was significantly faster in the group treated with alcohol (1.4 vs 2.2 hr). This study shows that ethanol increases the bioavailability of nifedipine and decreases the time for onset of increased heart rate.

Administration, Oral↗