Search PubMed⌕ Search

Biomedical subjects

A A Ali

Publications and source records attributed to A A Ali.

71 records · Page 4Linked to original sources

Analysis of QT interval in patients with idiopathic mitral valve prolapse.

Analysis of QT interval from repeated recordings was made in 56 patients with documented idiopathic mitral valve prolapse (IMVP). The results were compared with a control of 62 healthy volunteers in whom mitral valve prolapse was excluded by both phonocardiography and echocardiography and with two other standard populations, those of Simonson and co-workers and of Ashman. After correction for age, the maximum QT interval of the patients with IMVP exceeded the 97.5 percentile of Simonson population in 51 of 56 patients compared with only three of 62 subjects of the control group. The difference between the QT interval of patients from the upper limits of the predicted mean values of Simonson was significant (P less than 0.002). The mean QTC interval in patients with IMVP was 0.48 +/- 0.035 second compared with 0.038 +/- 0.025 second in the control subjects. The difference between the mean QTC interval in patients with IMVP and the control subjects was significant (P less than 0.005). Spontaneous prolongation in the mean QT interval was noted in 43 of 56 patients with IMVP (76.6 percent) compared with only two of 62 control subjects (3 percent). The incidence of episodic arrhythmias was 72 percent in patients with marked QTC prolongation (mean, 0.58 second) compared with 22.6 percent in patients with lesser degree of QTC prolongation (mean, 0.46 second). The results suggest that QT abnormality is common in patients with IMVP and may play an important role in the genesis of cardiac arrhythmia.

Adolescent↗

Plasma concentrations and clinical effects of lorazepam after oral administration.

The relation between plasma concentrations and properties of lorazepam administered orally as premedication was studied in patients undergoing minor surgery. The drug was found to be reliably absorbed in most subjects producing plasma concentrations similar to those reported after injection. Effective concentrations were obtained within 30-60 min, maintained for 4-6 h and were closely related to the action of the drug on memory and its sedative and anxiolytic properties. Its kinetics were described in about half of the subjects by a one-compartment model, but in others two compartments were required. Variable half-lives were found (range 9.3-32.1 h, mean about 20 h). Sufficient drug remains after 24 h to suggest that residual c.n.s. effects may still be present.

Administration, Oral↗

Solid dispersions of nitrofurantoin, ethotoin, and coumarin with polyethylene glycol 6000 and their coprecipitates with providone 25,000.

The influence of two linear polymers, polyethylene glycol 6000 and povidone 25,000, on the dissolution rate of three poorly soluble drugs, nitrofurantoin, ethotoin, and coumarin, was studied. Povidone 25,000 produced better drug solubilization than polyethylene glycol 6000 with the drug-polymer ratios studied, and an increase in the weight fraction of either polymer gave more rapid dissolution. TLC and IR studies ruled out any interaction between the drugs and polyethylene glycol 6000. IR spectrophotometry provided evidence that there was complex formation between nitrofurantoin and povidone 25,000, probably via hydrogen bonding.

Chemical Precipitation↗

Formation of liquid crystal and other non-fluid phases in emulsions containing non-ionic surfactants.

The relation between the phase distribution of components and the nature and properties of dispersions formed in a four-component system containing dodecane, water and two homogeneous non-ionic surfactants has been investigated by phase-rule techniques. Phase equilibrium diagrams for the four ternary systems were investigated and the phase boundaries for the various regions formed in these systems were defined by synthetic and analytical methods. In some of the ternary diagrams a narrow three-phase region occurs where 'gel' or liquid crystal as well as two isotropic liquid phases are present. Dispersions containing the gel phase were very stable. The four-component system has not been fully investigated due to the presence of extensive liquid crystal phases and three-phase regions. However, some distribution data for the quaternary system was obtained. In the presence of sufficient amounts of the short chain non-ionic surfactant C10H21(O.CH2.CH2)3OH, a three-liquid phase region occurs where multiple drops readily form.

Crystallization↗

Rectal perchlorate for unconscious patients prior to brain scintigraphy with pertechnetate: concise communication.

Patients undergoing brain scintigraphy with pertechnetate are frequently premedicated with oral perchlorate. However, the oral route is difficult to employ in unconscious or uncooperative patients or when oral intake is restricted. In such situations, rectal administration of sodium perchlorate dissolved in water is an effective alternative to oral administration.

Brain Diseases↗

Brain scanning with the Anger multiplane tomographic scanner as a second examination evaluation by the ROC method.

One hundred and one patients (43 abnormal, 58 normal) were re-examined with a commercial prototype of the Anger multiplane tomographic scanner after brain scintigraphy. The studies were interpreted independently by four observers of varying experience. Observer performance, in terms of ROC curves, was substantially better when interpreting the tomographic brain scans and camera scintigrams together or the tomographic scans alone than when interpreting the camera images alone. Re-examination with the scanner increases the accuracy of brain scintigraphy (observer performance) in cases in which there is difficulty distinguishing intracranial lesions from superficial foci of activity by camera scintigraphy alone.

Brain Neoplasms↗

Brain scanning with the Anger multiplane tomographic scanner as a primary examination. Evaluation by the ROC method.

A commercial prototype of the Anger multiplane tomographic scanner was compared with a scintillation camera, in terms of observer performance, as a primary instrument for brain scintigraphy. Observer performance (diagnostic accuracy), expressed as ROC curves, was slightly better when reading the tomographic scans than when reading the camera images. In brain scintigraphy of a general population, the scanner has a small advantage over the scintillation camera. This advantage is directly proportional to the fraction of cases in which there is difficulty differentiating intracranial lesions from superficial foci of activity on the camera image.

Brain Neoplasms↗

Endometrial cancer metastasis presenting as a grossly swollen toe.

Metastasis to the peripheral skeleton, especially in the face of low stage disease, is rare. This report describes the case of a 77-year-old lady with stage IC disease who underwent curative total abdominal hysterectomy and bilateral salpingo-oopherectomy 2 years prior to presenting with a painless gigantism of her fourth toe. A histologic diagnosis of dedifferentiated endometrial metastasis with sarcomatous differentiation was made following amputation of the toe. Osseous metastasis to bone is discussed in the context of endometrial carcinoma and the literature reviewed. This paper reports the first case of endometrial carcinoma metastasis presenting as gross swelling of a toe.

Aged↗

Invasive pulmonary aspergillosis complicating chronic obstructive pulmonary disease in an immunocompetent patient.

Immunocompromised individuals are susceptible to pulmonary aspergillus infection, but invasive aspergillus infection is extremely rare in the presence of normal immunity. We report a case of invasive aspergillosis in an immunocompetent 63-year-old male with chronic obstructive pulmonary disease (COPD). Patients with COPD may be at risk for developing pulmonary aspergillus infection, which should be considered as a diagnostic possibility in patients with unresolving pulmonary infection.

Aspergillosis↗