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Biomedical subjects

A Khan

Publications and source records attributed to A Khan.

At least 415 records · Page 23Linked to original sources
PubMed1992

Prevalence of mutans streptococci and dental caries in Pakistani children.

The caries status of two hundred and eighteen 12 year old school children from four schools of Karachi and Lahore was determined through a WHO pathfinder survey. In addition, the levels of mutans streptococci in the sample were estimated in order to define the proportion of children with high and low mutans levels. A mean DMFT of 1.82 (1.67-0.03-0.12), for decayed and filled teeth respectively; 42% were caries free. Four mutans streptococci; 22% had mutans class 0, 22% class 1, 31% class 2 and 25% class 3. The mean DMFT was respectively, 1.0 + 1.23, 0.98 + 1.52, 2.03 + 2.36 and 3.04 + 3.08. The difference was statistically significant. Twenty four children had 5 or more DMF all except two of them, belonging to mutans classes 2 or 3.

Child↗
PubMed1991

Quantification of glucose cycling and the extent of equilibration of glucose 6-phosphate with fructose 6-phosphate in islets from ob/ob mice.

Pancreatic islets from fed and fasted obese hyperglycaemic (ob/ob) mice were incubated with [1-14C]glucose at 5.5 mM and 16.7 mM, [1-14C]mannose at 16.7 mM, and 3H2O. Yields of 14CO2 and 14C-labelled lactate, and amounts of 14C from [1-14C]mannose incorporated into glucose and of 3H bound to C-2 of glucose, were measured. Glucose utilization was determined from yields of 3H2O from [5-3H]glucose. From the results using 14C, 32-43% of the hexoses phosphorylated to hexose 6-phosphate were estimated to have been dephosphorylated, i.e. cycled. Estimates of hexose cycling from 3H incorporation into glucose were similar. Differences in the ratios of 14C yields in CO2 and lactate indicated incomplete isotopic equilibration between glucose 6-phosphate and fructose 6-phosphate, making the estimates of cycling semi-quantitative. In the fasted state, a larger percentage of the hexose utilized went to lactate than in the fed state. Thus conversion of mannose into glucose in islets indicates the occurrence of glucose cycling in islets. Yields of 14C from [1-14C]mannose, compared with from [1-14C]glucose, provide an approach for quantifying the extent of this cycling. These data provide further evidence for extensive glucose cycling occurring in ob/ob islets in both the fed and the fasted state.

Animals↗
PubMed1991

The Lewis X antigen. A new paraffin section marker for Reed-Sternberg cells.

Using a monoclonal antibody specific to the Lewis X antigen (anti-Lex), the authors studied 103 cases of Hodgkin's disease (HD) in comparison with 57 cases of non-Hodgkin's lymphoma (NHL); three cases of granulocytic sarcoma (GS); two cases of malignant histiocytosis (MH); one case of monoblastic leukemia (ML); one case of interdigitating reticulum cell sarcoma (IRCS); six cases of histiocytosis X (HX); one case of reticulohistiocytoma (RH); 44 various reactive conditions of the lymph node (LN). Reed-Sternberg and related (R-S) cells stained selectively in 80 of 92 cases of HD (87.0%), excluding 11 cases of lymphocyte predominance type. The stain was better in B-5-fixed specimens than in formalin-fixed specimens, showing a dense deposit of reaction products at a paranuclear site and on the cell surface. The staining results were compared with those of Leu-M1 and found to be superior both qualitatively and quantitatively (detection rate of R-S cells: 87.0% versus 68.5% of Leu-M1). Granulocytes, rare epithelioid histiocytes, and some endothelial and/or erythrocytes also stained with anti-Lex. The stain had positive results in three cases of GS showing a diffuse cytoplasmic staining pattern. Of NHL, two of 29 peripheral T-cell lymphomas stained to show rare paranuclear deposits without cell surface staining. The stain had negative results in MH, ML, IRCS, HX, and RH. Of 45 reactive LN, minute subcapsular collections of Lewis X+, altered-appearing Langerhans'-like cells, were observed in all ten LN from human immunodeficiency virus (HIV)-associated persistent generalized lymphadenopathy (PGL). The stain had negative results in all other various reactive conditions of LN. In conclusion, Lewis X staining is useful as a marker for R-S cells in paraffin sections with staining results superior to those of Leu-M1. Lewis X staining also detects subcapsular clustering of altered-appearing Langerhans'-like cells in PGL, which has not been described previously and warrants additional study.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Morning or evening bright light treatment of winter depression? The significance of hypersomnia.

In a randomized crossover design 19 patients with winter depression were treated with 7 days of bright morning light (6:00 to 8:00 AM) and 7 days of evening light (7:00 to 9:00 PM). Bright light in the morning reduced the Hamilton Depression Rating Scale score from 22.3 to 5.5; bright light in the evening decreased the Hamilton score from 21.0 to 12.2. Improvement in the depression as measured by the Hamilton Depression Rating scores was greater with morning light compared with evening lights. Hypersomnia was associated (p less than 0.05) with a superior response to morning light.

Adult↗
PubMed1991

HIV-associated Hodgkin disease: a clinical study of 18 cases and review of the literature.

Intermediate- and high-grade B-cell non-Hodgkin lymphoma (NHL) occurring in a human immunodeficiency virus (HIV)-infected patient is considered diagnostic of the acquired immunodeficiency syndrome (AIDS). Other neoplasms (both hematopoietic and nonhematopoietic) have also been reported in patients with HIV infection, although none except Kaposi sarcoma carries the same diagnosis of AIDS as B-cell NHL in an HIV-infected host. There have been previous reports in the literature of Hodgkin disease (HD) in HIV-infected patients. We describe our clinical and pathological experience with HD from 1984-1989, in 18 patients with documented HIV infection and also review the literature on HD in HIV-infected patients. Almost all patients described herein presented with advanced disease and mixed cellularity histology and did very poorly despite some good initial responses to therapy. By statistical analysis, we found that the patients with HIV-associated HD had a strong tendency to be outside the age range seen in non-HIV-associated HD (P less than 0.005). We also discuss the possible relationship between HIV and HD and consider whether HIV-associated HD, like B-cell NHL, is a manifestation of AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Is a single tricyclic antidepressant trial an active treatment for psychotic depression?

1. A retrospective chart review of 256 consecutively admitted depressed inpatients assessed their treatment response to optimal somatic therapy. 2. There were no differences in treatment response between patients with Major Depressive Episode (MD) and Major Depression with Psychosis (MD-P). 3. In addition, twenty-six studies were reviewed to clarify the role of tricyclic antidepressants (TCA) in the treatment of MD-P. The authors conclude from this literature review that TCA's should not be considered an active treatment for MD-P patients.

Adult↗
PubMed1991

An investigation of environmental impact on health of workers at retail petrol pumps.

Ninety-four male pump workers, employed in 41 petrol filling stations in Kanpur (formerly Cawnpore) and Lucknow--both in the Ganges plain of north India--were clinically examined. Headache, redness in eyes, lacrimation and signs like coated and/or furred tongue, throat and/or conjunctival congestion and carious teeth were significantly higher (P less than 0.05) in workers exposed to petrol fumes than in controls, as also was the level of phenol in urine (P less than 0.01). Environmental measurements revealed higher concentrations of benzene, sulphur dioxide and photoionizable dust in the air at petrol stations, and most of the symptoms and signs could be attributed to petrol fumes and other environmental pollution.

Adolescent↗
PubMed1991

Sequential morphologic changes of elastase-induced pulmonary emphysema in pig lungs. Evaluation by high-resolution computed tomography.

The authors evaluated the early morphologic changes of elastase-induced pulmonary emphysema in the pig and correlated the findings with high-resolution computed tomography (HRCT). Nine Yorkshire pigs were included in this investigation; in seven, pulmonary emphysema was induced by 2 mg/kg body weight of elastase instilled selectively into the left lower lobe bronchus. Animals were studied by CT at 0, 1, 2, 3, 7, 14, and 21 days. At the completion of the experiment, the lungs were removed, inflated, fixed and dried, and subsequently sliced corresponding to the CT sections. The gross appearance, histologic appearance, and HRCT were correlated. On HRCT, sequential changes from early edema to development of emphysema were noted. Panlobular, centrilobular and paraseptal emphysema were observed. Elastase-induced pulmonary emphysema in the pig is a useful and reproducible animal model, and high-resolution computed tomography depicts the morphologic changes observed both by gross pathologic observations and histologic observations.

Animals↗
PubMed1991

The pharmacokinetics and pharmacodynamics of nifedipine at steady state during concomitant administration of cimetidine or high dose ranitidine.

Ranitidine may be used at doses of up to 300 mg twice daily in the healing of duodenal ulcers, and this study investigated the potential for a pharmacokinetic or pharmacodynamic interaction between nifedipine 10 mg three times daily and ranitidine 300 mg twice daily compared with cimetidine 800 mg daily and placebo in a randomised crossover study in 18 healthy male subjects. Twelve blood samples were taken on the fifth day in each treatment period and assayed for nifedipine by h.p.l.c. Pulse, blood pressure and ECG recordings were also taken. Cimetidine, but not ranitidine, produced significant changes in the pharmacokinetics of nifedipine at steady state. Mean +/- s.d. values of AUC were 105 +/- 40 micrograms l-1 for placebo treatment, 111 +/- 45 micrograms l-1 h for ranitidine and 211 +/- 64 micrograms l-1 h for cimetidine (P less than 0.001), and Cmax values were 33 +/- 14, 39 +/- 27 and 76 +/- 40 micrograms l-1 (P less than 0.001), respectively. Neither ranitidine nor cimetidine produced statistically significant changes in the pharmacological response to nifedipine.

Adult↗
PubMed1991

Tardive dyskinesia in the mentally retarded: comparison of prevalence, risk factors and topography with a schizophrenic population.

Thirty mentally retarded patients treated with neuroleptics for aberrant behavior were compared with 30 neuroleptic-treated schizophrenics for the presence, topography and risk factors associated with tardive dyskinesia (TD). In the total sample (n = 60), female sex, schizophrenic diagnosis and increasing age were associated with TD. The length of neuroleptic treatment and current neuroleptic dose were not significantly associated with TD. The only topographical difference in TD presentation was that the mentally retarded group had significantly more tongue involvement.

Adult↗
PubMed1991

Solitary pulmonary nodules: comparison of classification with standard, thin-section, and reference phantom CT.

Standard, thin-section, and reference phantom computed tomography (CT) were performed to evaluate 75 consecutive patients with solitary pulmonary nodules. Follow-up was available for 62 nodules in 59 patients; 53 of the nodules were benign and nine were malignant. Twenty-one of the 62 nodules were assessed as benign with thin-section CT, while 33 of the 62 nodules were assessed as benign with reference phantom CT. Two of the nodules classified as benign with both thin-section and reference phantom CT proved to be malignant (a peripheral, ossified carcinoid and a 3.5-cm-diameter calcified carcinoma). The sensitivity of reference phantom CT (58%) for classification of benign nodules was higher than the sensitivity of thin-section CT (36%). The sensitivity of standard CT was lowest (12%). The presence of fat at thin-section CT was a reliable criterion for benignancy in six hamartomas. While both thin-section and reference phantom CT were useful in the identification of benign pulmonary nodules, reference phantom CT increased sensitivity by 22% compared with thin-section CT.

Adult↗
PubMed1991

Internal maxillary artery variability in the pterygopalatine fossa.

The third segment or pterygopalatine branch of the internal maxillary artery has variable branching in the pterygopalatine fossa. This variability in branching can lead to failure in controlling persistent nasal epistaxis by transantral ligation. Although the surgical approach has been previously studied, a systematic classification of this branching has not been previously reported. Through the performance of serial cadaver dissections in the PPF, we have demonstrated the anatomic course and variations of this third segment and offer a relatively simple classification system.

Adipose Tissue↗
PubMed1991

Ambulatory blood pressure monitoring evaluation of a semi-automated device.

The accuracy of a semi-automated ambulatory blood pressure monitoring device (the Instrumedix 'Personal Blood Pressure Transmitter') was assessed in 36 patients undergoing diagnostic cardiac catheterisation. Blood pressure readings measured by the device and by a standard manual sphygmomanometer were compared with simultaneous intra-aortic pressure measured directly via the catheter. No measurement size trends were identified for either of the two comparisons. Compared to direct intra-aortic pressure measurement, the manual sphygmomanometer gave lower systolic (p less than 0.05), and higher diastolic readings (p less than 0.01), while the semi-automated device gave slightly higher readings for both systolic (not significant: p greater than 0.05) and diastolic (p greater than 0.05) pressure. In this assessment the semi-automated device provided at least as accurate a reflection of intra-aortic pressure as did standard manual sphygmomanometry. This device is an accurate tool for the ambulatory assessment of blood pressure where adequacy of treatment or correctness of the diagnosis is in question.

Adult↗
PubMed1991

Chronic steroid dependent asthma and pulmonary function.

The authors followed 84 asthma clinic patients, with an average age of 49 years, for 12 years. Pulmonary function studies consisting of forced expiratory volume in one second and forced vital capacity were performed upon initial evaluation and quarterly re-evaluation.

Asthma↗
PubMed1991

Early experience with percutaneous transluminal coronary angioplasty in unstable angina.

Percutaneous transluminal coronary angioplasty was done in 13 of 105 patients with unstable angina, 10 of whom were males. Diagnostic coronary angiography revealed single vessel disease in 10 cases and two vessel disease in 3 cases; the degree of stenosis varied from 70-90%. Only a single major coronary artery was dilated. Immediate angiographic success was achieved in 12(92.3%) cases. The success rate at the time of discharge from hospital was 10 (76.9%) cases. Immediate complications encountered were acute myocardial infarction in 2 cases, they refused coronary artery bypass grafting and unsuccessful dilation in 1 case. No death occurred during the hospital stay. During follow-up of 6-9 months, 8 patients were symptom free (66.6%), 2 patients required repeat percutaneous transluminal coronary angioplasty and 2 patients died. In conclusion, percutaneous transluminal coronary angioplasty may be undertaken relatively safely in unstable angina, it leads to substantial improvement in symptoms during the early follow-up period. This therapeutic approach is highly beneficial particularly in single vessel disease.

Adult↗