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H Habibi

Publications and source records attributed to H Habibi.

9 recordsLinked to original sources
PubMed2007

Role of gonadotropin-releasing hormone (GnRH) in the regulation of gonadal differentiation in the gilthead seabream (Sparus aurata).

It has been proposed that gonadotropin-releasing hormone (GnRH) plays an autocrine/paracrine regulatory role in mammalian and fish ovaries. The marine teleost gilthead seabream is an interesting model since, during the life span of the fish, gonadal tissues develop first as testes, which then regress allowing the development of ovarian follicles. Recent studies carried out in ovaries of the gilthead seabream have demonstrated that various GnRH transcripts as well as GnRH splicing variants are expressed. The mRNA level of several GnRH forms in the female and male areas of the switching gonad, and their possible role in this process, were further investigated. The results here reported show that sGnRH, cGnRH-II, and sbGnRH transcripts are locally expressed during gilthead seabream gonadal differentiation; the expression of the three GnRH forms was found to differ among the morphologically defined areas of the switching gonad, as demonstrated by applying reverse transcription-polymerase chain reaction (RT-PCR), together with in situ hybridization, and semiquantitative PCR analyses. Moreover, the hypothesis that GnRH forms may regulate testicular regression via an apoptotic mechanism was investigated by analyzing the different areas of switching gonads for caspase-3 activity as a measure of apoptosis. Our results showed a marked increase of caspase-3 activity in the area corresponding to the regressing testes in which a significant decrease of testosterone production was also found. The present findings demonstrate that the changes in the endogenous GnRH transcripts could be related with the gonadal differentiation in gilthead seabream, and that exogenous GnRH plays a role by stimulating apoptosis in the degenerating testis.

Alternative Splicing↗
PubMed2003

A gonadotropin-releasing hormone insensitive, thapsigargin-sensitive Ca2+ store reduces basal gonadotropin exocytosis and gene expression: comparison with agonist-sensitive Ca2+ stores.

We examined whether distinct Ca2+ stores differentially control basal and gonadotropin (GTH-II)-releasing hormone (GnRH)-evoked GTH-II release, long-term GTH-II secretion and contents, and GTH-II-beta mRNA expression in goldfish. Thapsigargin (Tg)-sensitive Ca2+ stores mediated neither caffeine-evoked GTH-II release, nor salmon (s)GnRH- and chicken (c)GnRH-II-stimulated secretion; the latter responses were previously shown to involve ryanodine (Ry)-sensitive Ca2+ stores. Surprisingly, Tg decreased basal GTH-II release. This response was attenuated by prior exposure to sGnRH and caffeine, but was insensitive to the phosphatase inhibitor okadaic acid, the inhibitor of constitutive release brefeldin A and cGnRH-II. GTH-II-beta mRNA expression was decreased at 24 h by 2 microm Tg, and by inhibiting (10 microm Ry) and stimulating (1 nm Ry) Ry receptors. Transient increases in GTH-II-beta mRNA were observed at 2 h and 12 h following 10 microm and 1 nm Ry treatment, respectively. Effects of Tg, Ry and GnRH on long-term GTH-II secretion, contents and apparent production differed from one another, and these changes were not well correlated with changes in GTH-II-beta mRNA expression. Our data show that GTH-II secretion, storage and transcription can be independently controlled by distinct Ca2+ stores.

Animals↗
PubMed1995

Effect of amlodipine, atenolol and their combination on myocardial ischemia during treadmill exercise and ambulatory monitoring. Canadian Amlodipine/Atenolol in Silent Ischemia Study (CASIS) Investigators.

OBJECTIVES: This study compared the effects of amlodipine, atenolol and their combination on ischemia during treadmill testing and 48-h ambulatory monitoring. BACKGROUND: It is not known whether anti-ischemic drugs exert similar effects on ischemia during ambulatory monitoring and exercise treadmill testing. METHODS: Patients with stable coronary artery disease and ischemia during treadmill testing and ambulatory monitoring were randomized to receive amlodipine (n = 51) or atenolol (n = 49). Each group underwent a counterbalanced, crossover evaluation of single drug and placebo, followed by evaluation of the combination. RESULTS: Amlodipine and the combination prolonged exercise time to 0.1-mV ST segment depression by 29% and 34%, respectively (p < 0.001) versus 3% for atenolol (p = NS). During ambulatory monitoring, the frequency of ischemic episodes decreased by 28% with amlodipine (p = 0.083 [NS]), by 57% with atenolol (p < 0.001) and by 72% with the combination (p < 0.05 vs. both single drugs; p < 0.001 vs. placebo). Suppression of ischemia during exercise testing and ambulatory monitoring was similar in patients with and without exercise-induced angina. Exercise time to angina improved by 29% with amlodipine (p < 0.01), by 16% with atenolol (p < 0.05) and by 39% with the combination (p < 0.005 vs. placebo, atenolol and amlodipine). In patients with angina, total exercise time improved by 16% with amlodipine (p < 0.001), by 4% with atenolol (p = NS) and by 19% with the combination (p < 0.05 vs. placebo and either single drug). In those patients without angina, no therapy significantly improved total exercise time. CONCLUSIONS: Ischemia during treadmill testing was more effectively suppressed by amlodipine, whereas ischemia during ambulatory monitoring was more effectively suppressed by atenolol. The combination was more effective than either single drug in both settings.

Amlodipine↗
PubMed1994

[Norplant contraception at the Rabta Tunis maternity hospital].

612 women had the benefit of contraceptive implants in the Maternity Hospital of La Rabta in Tunis over a period of 5 years (1988-1992). This study aimed at analysing the tolerance of this method by studying a group of 508 normal women and 104 women at risk (58 women were heart-diseased, 22 nursing, 13 diabetic, 11 hypertensive). The typical woman in this group is thirty years old, having 3 children, and weighing 61 kg. The implants were most of the cases withdrawn because of problems related to the menstrual cycle that were observed in 37% of the cases, equally distributed among both groups of the series. Contraceptive implants failed in 1.79% of the cases.

Adolescent↗
PubMed1993

Relative importance of psychologic traits and severity of ischemia in causing angina during treadmill exercise. Canadian Amlodipine/Atenolol in Silent Ischemia Study (CASIS) Investigators.

OBJECTIVES: This study was conducted to compare the influence of psychologic traits versus ischemia severity on the occurrence of angina during treadmill exercise. BACKGROUND: Some studies suggest that angina is associated with certain psychologic traits, whereas others show an association with more severe ischemia. The relative influence of these two factors and the extent to which they interact are not known. METHODS: Off-drug treadmill exercise testing and a battery of psychologic tests were performed on 122 patients with known coronary artery disease. Psychologic tests measured sensitivity to physical symptoms, denial and deception, type A behavior, anger, hostility, depression, marital adjustment and amount of external stress. Stepwise logistic regression was used to determine the independent association of psychologic traits, ischemic threshold and exercise tolerance with the occurrence of angina. RESULTS: Angina during treadmill exercise was reported by 66 of 122 patients. On univariate testing, angina was positively associated with sensitivity to physical symptoms (p < 0.001), type A behavior (p = 0.021) and depression (p = 0.032) and was negatively associated with exercise tolerance (p < 0.001) and work load threshold for ischemia (p < 0.01). Multivariate analysis revealed independent and additive associations of angina with sensitivity to physical symptoms (p = 0.003), exercise capacity (p = 0.003) and work load threshold for ischemia (p = 0.018). Once these were included in a logistic model, depression and type A behavior were no longer significant. Other psychologic traits showed no association with angina. CONCLUSIONS: Sensitivity to physical symptoms, ischemic threshold and exercise tolerance are independently associated with angina, with sensitivity to physical symptoms having the stronger influence. The physiologic and psychologic mechanisms underlying symptom perception have an influence on angina that is independent of and additive to the severity of underlying ischemia.

Amlodipine↗
PubMed1985

The effect of low-dose cyclophosphamide and immunologic exposure upon growth of established Dunning R-3327-G subline rat prostate adenocarcinomas.

Utilizing the Dunning rat prostate adenocarcinoma, a low dose of cyclophosphamide (CY), 30 mg/kg, administered either alone or following diethylstilbestrol (DES) therapy, was as effective as higher levels of CY (100 mg/kg) in ability to initiate tumor regression. A lower dose (10 mg/kg) of CY was initially ineffective. Animals which had been injected with tumor an additional 10 days prior to initiation of CY treatment were apparently more responsive to this mode of chemotherapy. The effect of this additional 10 days of immunologic exposure supports the belief that the activity of CY is augmented by the presence of immunologic competence. All animals which responded favorably toward therapy utilizing CY, alone or in combination with DES, were similarly able to reject subsequent tumor challenges. It is thought that low-dose CY may reduce the immunosuppressive effects observed with higher levels and presumably preserve the helper T cell population necessary to mount secondary immune responses.

Adenocarcinoma↗
PubMed1984

Pelvic lymph node dissection in prostate cancer.

The results of pelvic lymph node dissections in 105 prostate cancer patients were analyzed to compare the clinical with the pathologic stages. Twenty-four per cent of patients clinically believed to be node-negative had positive nodal involvement with cancer.

Aged↗
PubMed1979

Case report of an ovarian hydatid cyst.

Hydatid cyst is a parasitic disease caused by Taenia echinococcus. The first and most important site for this parasite is the liver. Secondary involvement of the pelvic organs is seen. However, the primary involvement is very rare. Here we are reporting a case with primary involvement of the ovary which underwent laparotomy and was proven by microscopic studies.

Echinococcosis↗