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Biomedical subjects

A Dupont

Publications and source records attributed to A Dupont.

At least 181 records · Page 10Linked to original sources

New hormonal therapy in prostatic carcinoma: combined treatment with an LHRH agonist and an antiandrogen.

In order to block the influence of androgens from all sources on the growth of prostatic cancer, we have used a new hormonal therapy based on medical castration achieved with the potent LHRH agonist [D-Ser(TBU)6, des-Gly-NH2(10)]LHRH ethylamide (HOE-766) combined with the administration of a pure antiandrogen that neutralizes the action of adrenal androgens as well as those still secreted in low amounts by the testis during LHRH agonist treatment. This study was performed in ten patients with advanced prostatic carcinoma (9 at stage D2 and one at stage C). Bone pain, prostatism and general well-being were 60 to 90% improved within one month after starting treatment in all patients. After 2 months of treatment, minimal bone pain remained only in one patient who was originally bedridden. Bone scanning showed a 70 to 90% decrease in uptake after 3 to 5 months of treatment in the patients studied. Acid phosphatase levels were 60 to 90% reduced after 2 months of treatment in 3 out of the 4 patients who had elevated levels before therapy. Marked objective and subjective improvement was thus rapidly observed in 9 out of 10 patients treated with the combined therapy, while, in the other patient at stage C, subjective improvement could be documented. Although preliminary, this study indicates that a combined hormonal therapy which neutralizes all androgenic influences on peripheral tissues is of potential benefit in prostatic cancer. Moreover, the ease of application as well as the lack of secondary effects of the present approach should make possible its use early in the disease and should thus minimize the development of metastases and androgen-resistant cell clones. Randomized prospective studies on this potentially beneficial therapy are warranted.

Adenocarcinoma↗

[Metastasis of visceral tumors in intracranial tumors. Apropos of a metastasis of a lung cancer in an intracranial meningioma].

In a 52 years old man a backward epilepsy revealed a left fronto parietal tumor. The histopathological study shows that it is a meningial tumor composed around by meningocytic proliferation with a metastasis of lung cancer in the middle. This fact was proved only two months after neurosurgical intervention. Thirty three cases of cancer with metastasis in an intracranial primitive tumor have been collected in the literature. The authors study the clinical aspects and etiopathogenic hypothesis of this surprising anatomopathological fact.

Brain↗

Effect of hypophysectomy and pituitary stalk transection on alpha-melanocyte-stimulating hormone-like immunoreactivity in the brain of the frog, Rana ridibunda Pallas.

The existence of an alpha-MSH-like molecule in the frog brain led us to investigate the role of the pituitary gland in the maintenance of the alpha-MSH content in 3 different regions of the brain. Acetic acid extracts of hypothalamus, rhombencephalon and telencephalon were analyzed by means of a highly specific radioimmunoassay for alpha-MSH in normal, sham-operated, pituitary disconnected and hypophysectomized frogs. Transection of the pituitary stalk gave rise to a significant decrease in alpha-MSH content in the intermediate lobe of the pituitary gland (-71% after 3 days), but did not affect alpha-MSH content in the distal lobe or in the brain. Eight days after total hypophysectomy, an alpha-MSH immunoreactive compound, co-eluting with synthetic alpha-MSH on Sephadex G-25, was found in the 3 brain regions studied. Removal of the whole pituitary gland did not significantly modify alpha-MSH content in the hypothalamus and the telencephalon. A slight increase in alpha-MSH was even observed in the rhombencephalon of hypophysectomized animals. Furthermore, no modification in alpha-MSH immunoreactivity occurred in any region of hypophysectomized animals. These results demonstrate the existence of alpha-MSH-like material in the brain of Rana ridibunda and establish that brain alpha-MSH in the frog is not of pituitary origin.

Animals↗

Effects of chronic estrogen treatment on dopamine concentrations and turnover in discrete brain nuclei of ovariectomized rats.

We investigated the effects of chronic estrogen treatment in ovariectomized rats on the concentration of dopamine in 33 discrete brain nuclei. In order to assess estrogen's influence on dopamine turnover, some of the rats were administered alpha-methyl-p-tyrosine. Estrogen treatment reduced the concentrations of dopamine in the nucleus accumbens septi, striatum, median eminence, nucleus anterior hypothalami, nucleus suprachiasmaticus, nucleus arcuate IV-V, area ventralis tegmenti, interpeduncular nucleus and nucleus interstitialis striae terminalis. Treatment was without effect on dopamine turnover in all areas studied.

Animals↗

Changes in the beta-endorphin content of discrete hypothalamic nuclei during the estrous cycle of the rat.

Concentrations of beta-endorphin were measured in discrete brain nuclei of 4-day cycling rats on each day of the estrous cycle. On the afternoon of proestrus beta-endorphin levels were significantly higher in median eminence and suprachiasmatic nucleus, and lower in arcuate nucleus, when compared to levels found on other days of the cycle. These changes coincided with the peak of plasma prolactin, which was blocked by prior administration of naloxone.

Animals↗

Regional distributions of somatostatin and cholecystokinin-like immunoreactivities in rat and bovine brain.

The distribution of somatostatin- and cholecystokinin octapeptide (CCK-8)-like immunoreactivities in the central nervous system of bovine and rat has been studied using a sensitive and specific radioimmunoassay. The most interesting information is the high concentration of CCK-8 in the various cortical areas in rat and bovine. The nuclei of amygdala contain the highest amount of octapeptide in rat while in bovine brain, this structure contains the second highest concentration after polus frontalis.

Animals↗

Effect of neonatal thyroid deficiency on the catecholamine, substance P, and thyrotropin-releasing hormone contents of discrete rat brain nuclei.

The effects of neonatal thyroidectomy and thyroid hormone replacement therapy on the development of catecholamine-, TRH-, and substance P-containing neurons in discrete rat brain nuclei were studied. Newborn male rats were rendered hypothyroid by the injection of 125 muCi 131I and, after 45 days, were compared with normal littermate controls and 131I-injected animals subsequently maintained on T4 injections. The peptide or catecholamine content of discrete brain nuclei removed by punches of frozen brain slices was measured by RIA or radioenzymatic assay, respectively. The success of the thyroidectomy was verified by criteria of weight, length, plasma T4, and pituitary GH content. Animals receiving T4 replacement therapy were indistinguishable from normal littermates. Substance P was measured in 32 different brain nuclei and was significantly increased in 19 of these areas in hypothyroid animals. No changes in norepinephrine were detected, and the dopamine content of all but 3 brain nuclei was increased by thyroidectomy. The TRH concentration was drastically reduced in the median eminence of hypothyroid animals and also changed in 3 other extrahypothalamic areas. All of the changes seen in catecholamine, TRH, and substance P distribution in hypothyroid animals were completely reversed by T4 replacement therapy. These results demonstrate changes in brain peptide neurotransmitters during the hypothyroid state and open new vistas for comprehension of biochemical mechanisms underlying central nervous system malfunction.

Animals↗

[Surgical treatment of intestinal radio-lesions. 53 patients operated, out of 171 radio-lesions among 7301 irradiated (author's transl)].

Results of a complete and homogenous series by the Medical Team of the Centre Anti-Cancéreux.--2,45% of abdomino-pelvic irradiations among 6516 cases,--but only 0.78 are serious and need surgery (i.e. 1/3 of the radio-lesions). The study concerned 65 cases;--during the same period, medical treatment alone controlled 51 cases of rectitis and 51 stenoses. The interval after irradiation is variable: 33 times, it was shorter than 1 year, in 32 cases, it was longer, up to 13 years. The plan for therapy is to continue the medical treatment as well as possible and to operate only in case of absolute need, but before obstruction;--to prefer immediate resection to internal derivation. The 27 resections resulted in 18 recoveries and 9 cases of peritonitis. In spite of the serious nature of the initial irradiated lesion, followed by this complicated radio-lesion, we observed: 28% of 5-year survivals, and over 10 years in 9 cases.

Humans↗