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K Barakat

Publications and source records attributed to K Barakat.

26 records · Page 2Linked to original sources
PubMed1996

Growth hormone (GH) and insulin-like growth factor I responses after treatments with an orally active GH secretagogue L-163,255 in swine.

L-163,255 is a potent orally active spiropiperidine GH secretagogue. When administered iv or orally, L-163,255 caused GH to be increased in a dose-related manner, with a return to baseline by 90 min. After iv administrations of saline and L-163,255 at 1, 3, and 10 micrograms/kg, GH areas under the curves (GH AUCs) over 120 min were 377 +/- 136, 1151 +/- 413 (P < 0.05), 795 +/- 413 (P = NS), and 1770 +/- 416 ng.min/ml (P < 0.01), and peak GH concentrations were 8 +/- 3, 16 +/- 7 (P = NS), 17 +/- 5 (P = NS), and 43 +/- 12 ng/ml (P < 0.01), respectively. No changes in plasma cortisol concentrations were noted. After oral administrations at 3, 10, and 30 micrograms/kg, GH AUCs over 180 min were 1133 +/- 154, 1246 +/- 129 (P = NS), and 1551 +/- 210 ng.min/ml (P = NS), and peak GH concentrations were 7 +/- 2, 11 +/- 3 (P = NS), and 23 +/- 6 ng/ml (P < 0.01), respectively. After administration in feed, L-163,255 caused a dose-related increase in GH, with an initial peak observed at 60 min for both 30 and 300 micrograms/kg dose groups, and remained elevated above baseline through 180 min for the high dose group only. GH AUCS for 180 min posttreatment were 929 +/- 134 and 1897 +/- 244 ng.min/ml, and peak GH concentrations were 9 +/- 2 and 22 +/- 4 ng/ml for the 30 and 300 micrograms/kg doses prepared in 150 g feed, respectively. When provided in feed ad libitum over the 72-h period, mean plasma insulin-like growth factor I levels increased 15%, 62% (P < 0.01), and 109% (P < 0.01) in the untreated, treated with L-163,255 at 360 ppm, or treated with porcine somatotropin groups, respectively. Repeated iv administration of L-163,255 at 1 mg/kg once daily over 14 days resulted in an initial marked GH response, followed by a much reduced, but significantly elevated, GH response over the saline control values on subsequent treatment days. Repeated iv treatments with L-163,255 also resulted in an elevated insulin-like growth factor I level (approximately 60%) over that in saline controls. Compared to those in saline controls, plasma cortisol concentrations tended to be increased after the initial dose of L-163,255, but no significant increases were noted on days 7 and 14 in the L-163,255 group. The results of these studies indicate that L-163,255 is an orally active GH secretagogue suitable for long term efficacy studies in swine.

Administration, Oral↗
PubMed1989

The hypoechoic band: a normal finding on testicular sonography.

High-resolution sonograms were obtained in 119 patients in whom intrascrotal disease was suspected on the basis of history and physical findings. In 20 of these patients, a total of 22 conspicuous hypoechoic intratesticular bands (18 unilateral and four bilateral) were seen in the middle third of the testicle on scans obtained axially or slightly oblique to conventional axial scans. The bands were up to 3 mm wide and 3 cm long. The bands were on the side with suspected disease in six patients. Of these, three patients had a small epididymal cyst, one had a mild hydrocele, and two had no other sonographic finding. The remaining 16 bands were on the side opposite that with clinically suspected disease and were seen in otherwise normal testes. Follow-up examination in 11 of the 20 patients with the band showed no change. In four of eight patients examined with pulsed Doppler sonography, a normal low-resistance waveform was seen that was characteristic of intratesticular arteries (with gradual descent after peak systole and relatively high diastolic flow). In three of these patients, color Doppler imaging corroborated the presence of arterial flow, which did not fill the entire width of the band, thus suggesting an additional venous component of lower velocity in the band. Identification of flow in only half the cases may have been caused by the limitations in sensitivity of the equipment. We conclude that the hypoechoic bands noted on gray-scale testicular sonography are caused by a normal variant of intratesticular vessels, artery and vein, and that they are of no clinical significance.

Humans↗
PubMedDate not supplied

Selection bias in the management of unstable angina.

OBJECTIVES: To examine the criteria for selecting patients presenting with unstable angina for cardiac catheterisation and to assess the extent to which these criteria successfully incorporate high risk groups. METHODS AND RESULTS: This was a prospective cohort study of 517 patients admitted with unstable angina with 12 months follow-up; 139 patients (26.9%) had cardiac catheterisation 32 days or longer after presentation. The odds of early catheterisation were increased by regional ST segment depression on the presenting ECG (odds ratio (OR) 1.70, 95% confidence intervals (CI) 1.01-2.87) and ongoing ischaemic chest pain more than 12 hours after admission (OR 9.72, CI 6.10-15.49), and reduced by age over 65 years (OR 0.56, 95% CI 0.35-0.90) and heart failure (OR 0.26, CI 0.11-0.64). The 12-month rates of myocardial infarction (MI) or death were 8.6% and 17.7% (p = 0.01) in patients who were and were not referred for early cardiac catheterisation, respectively. Survival analysis showed that the odds of MI and death in the first 12 months were increased substantially by heart failure (OR 2.82, 95% CI 1.53-5.20) and age over 65 (OR 1.91, 95% CI 1.13-3.23). CONCLUSION: Selection for early cardiac catheterisation in this unstable angina population was largely ischaemia-driven, based on ongoing chest pain and ST segment depression. This policy was associated with a low event rate in the ischaemic group, but it failed to target elderly patients and those with heart failure who were at greatest risk of MI and death during the first year.

Aged↗