Search PubMed⌕ Search

Biomedical subjects

J Rousseau

Publications and source records attributed to J Rousseau.

At least 91 records · Page 5Linked to original sources

Synthesis, receptor binding, and tissue distribution of (17 alpha,20E)- and (17 alpha,20Z)-21-[125I]iodo-19-norpregna-1,3,5(10), 20-tetraene-3,17-diol .

The isomeric (17 alpha,20E)- and (17 alpha,20Z)-(iodovinyl)estradiol derivatives 3 and 6, and their no-carrier-added (nca) [125I]iodovinyl analogues, were tested for their relative target tissue retention and binding affinity for the estrogen receptor. The (iodovinyl)estradiols 3 and 6 were prepared via destannylation of the (17 alpha,20E)- and (17 alpha,20Z)-tributylstannyl precursors 2 and 4 with retention of configuration. Selective formation of the E or Z isomers 2 and 4 during the reaction of 17 alpha-ethynylestradiol 1a with tri-n-butyltin hydride was controlled by the presence or absence of the catalyst, the polarity of the solvent, and the reaction temperature. The nca [125I]iodovinyl analogues [125I]-3a and [125I]-6a were obtained in good radiochemical yield and high purity by treatment of 2a and 4a with [125I]NaI in the presence of H2O2 and chloroamine-T, respectively. Of the two isomeric iodovinyl derivatives 3 and 6, the 20Z isomer 6a exhibited the highest receptor binding affinity and the [125I]-6a gave the highest in vivo receptor-mediated target tissue uptake.

Animals↗

Ifenprodil and SL 82.0715 as cerebral anti-ischemic agents. I. Evidence for efficacy in models of focal cerebral ischemia.

Recent studies have strongly implicated the excitatory neurotransmitter glutamate in the cascade of pathological mechanisms that cause neuronal loss after certain types of brain ischemia. The neurotoxic effects of glutamate are mediated, at least in global ischemia, via NMDA receptors. In the present study we have examined the effects of compounds that possess NMDA receptor antagonist properties (ifenprodil, SL 82.0715 [(+/-)-alpha-(4-chlorophenyl)-4-[(4-fluorophenyl)methyl]- 1-piperidineethanol] and 1-[1-(2-thienyl)cyclohexyl]piperidine) on the histological consequences of focal, as opposed to global, cerebral ischemia in both the rat and the cat. Ifenprodil (0.3-3 mg/kg i.v.) administered as a perfusion over 3 hr after occlusion of the feline middle cerebral artery reduced the volume of infarcted tissue (measured 4 days after occlusion) in a dose-related manner. At the highest dose a 42% reduction of infarcted volume was noted, essentially in cortical tissue. In an identical protocol, a derivative of ifenprodil, SL 82.0715, reduced the volume of infarction in a manner comparable to that described for ifenprodil. As SL 82.0715 possesses better p.o. bioavailability, this compound was also evaluated in the rat, again after middle cerebral artery occlusion. First administered 30 min after the induction of ischemia, SL 82.0715 (1 and 10 mg/kg p.o.) reduced infarction volume by 34 and 48%, respectively. The quantitative histology was performed 2 days after middle cerebral artery occlusion. The noncompetitive receptor antagonist, 1-[1-(2-thienyl)cyclohexyl]piperidine, administered (1 mg/kg i.p.) before the induction of focal ischemia, similarly and significantly decreased the final volume of infarction. As both ifenprodil and SL 82.0715 are noncompetitive antagonists of the NMDA receptor, two conclusions may be drawn from the present investigation. First, NMDA antagonism by ifenprodil and its derivative is an effective approach for tissue sparing in animal models of stroke and brain infarction. Second, these pharmacological observations provide evidence for the involvement of excitatory amino-acid induced-neurotoxicity in the evolution and consequences of focal cerebral ischemia.

Animals↗

Synthesis of a series of compounds related to betaxolol, a new beta 1-adrenoceptor antagonist with a pharmacological and pharmacokinetic profile optimized for the treatment of chronic cardiovascular diseases.

A series of para-substituted phenoxypropanolamines has been synthesized and tested for beta-adrenoceptor blocking activity. Some derivatives (8, 11, 12, 20, 21) exhibited greater in vitro potency than the reference drugs metoprolol and propranolol. This series, in contrast to propranolol but similar to metoprolol, possesses cardioselectivity. The 3-[p-[(cycloalkylmethoxy)ethyl]phenoxy]-1-substituted-amino-2-prop anol derivatives 8 (cyclopropylmethoxyethyl: betaxolol) and 11 (cyclobutylmethoxyethyl) produced antihypertensive effects in spontaneously hypertensive rats. Betaxolol (Kerlon, 8) was found to exhibit an appropriate preclinical pharmacological and human pharmacokinetic profile (elevated oral bioavailability and prolonged plasma half-life) for the treatment of chronic cardiovascular diseases such as hypertension and angina.

Adrenergic beta-Antagonists↗

Pulsed-field electrophoresis: application of a computer model to the separation of large DNA molecules.

The biased reptation theory has been applied to the pulsed-field electrophoresis of DNA in agarose gels. A computer simulation of the theoretical model that calculates the mobility of large DNA molecules as a function of agarose pore size, DNA chain properties, and electric field conditions has been used to generate mobility curves for DNA molecules in the size range of the larger yeast chromosomes. Pulsed-field electrophoresis experiments resulting in the establishment of an electrophoretic karyotype for yeast, where the mobility of the DNA fragments is a monotonic function of molecular size for the entire size range that is resolved (200-2200 kilobase pairs), has been compared to the theoretical mobility curves generated by the computer model. The various physical mechanisms and experimental conditions responsible for band inversion and improved electrophoretic separation are identified and discussed in the framework of the model.

Chromosomes↗

[A swollen leg disclosing a popliteal cyst. Apropos of a misleading case].

A patient was admitted with a clinical suspicion of left sural thrombophlebitis. Analysis of the clinical features and the results of rheoplethysmography, phlebography, arteriography and, most importantly, ultrasonography led to the diagnosis of popliteal synovial cyst and demonstrated the vascular repercussions of this lesions responsible for the swollen leg. A review of the literature confirms the frequently misleading clinical features of popliteal cysts. The authors present a strategy for the investigation of these cases, based on vascular functional investigations and in particular ultrasonography.

Angiography↗

Synthesis, tissue distribution and tumor uptake of 99mTc- and 67Ga-tetrasulfophthalocyanine.

Complexes of tetrasulfophthalocyanine with 99mTc, 69Ga and 67Ga were prepared by the condensation of sulfophthalic acid with the appropriate metal-species. The Ga-complex was also obtained by exchange of the central hydrogens of the empty tetrasulfophthalocyanine. The labeled complexes were purified by thin layer chromatography and characterized by their chromatographic properties. Their biodistribution in rabbits and tumor-bearing rats revealed that most of the radioactivity accumulated in the kidneys, liver, ovaries, adrenals and spleen. Comparison of these distribution pattern with those of [99mTc]pertechnetate and 67Ga-citrate confirmed the in vivo stability of the labeled complexes. The 67Ga-complex reached better tumor-to-blood and tumor-to-muscle ratios than 67Ga-citrate.

Adenocarcinoma↗

[Congenital factor XII deficiency: a rare cause of increased activated cephalin time].

The fortuitous detection of an increased activated cephalin clotting time is often dependent on defects of the blood-clotting factors synthesized by the liver, haemophilia or von Willebrand's disease, circulating anticoagulants or specific deficiencies of various factors necessary for blood-clotting mechanisms. Much more rarely, it may be due to an isolated Hageman factor defect. This deficiency does not lead to an increased bleeding tendency and surgery has proved surprisingly uneventful. On the other hand, thromboembolic events may appear. Being and inherited disease with autosomal recessive transmission, the discovery of Hageman factor deficiency must lead to a complete family investigation.

Adult↗

Incidence of Hb Barts and alpha-thalassaemia genotypes in a South African population.

The cord blood of 1,207 randomly selected neonates from the Cape Coloured population of South Africa was analysed for the presence of Hb Barts. 40 individuals (3.3%) had detectable Hb Barts levels with values ranging from 1.1 to 7.3%. Restriction enzyme analysis of DNA from subjects with Hb Barts showed that 85% of the cases studied had the genotypes -alpha 3.7/alpha alpha or -alpha 3.7/-alpha 3.7. The observed frequency of the -alpha/alpha alpha genotype was much lower than the expected frequency which suggests that this genotype is often not associated with detectable levels of Hb Barts. Mapping of the sigma-globin locus in three subjects with HbH disease revealed the presence of the--SEA/alpha-thalassaemia determinant in this population.

DNA↗

[Cancer of the anal canal. Results of the treatment of a series of 195 cases].

Between 1968 and 1982, 195 patients with invasive anal canal carcinoma were treated at Institut Curie (Paris, France). There were 168 females and 27 males --sex-ratio: 5.7/1, mean age: 67 +/- 11 yrs. (range: 38-85 yrs.). The initial size of the tumors was analyzed according to the circumferential invasion of the anal canal. The tumor involved 1/4 of the circumference in 49 cases, 1/2 of the circumference in 108 cases, 3/4 of the circumference in 22 cases and the whole circumference in 16 cases. Pathological examination revealed 20 cloacogenic carcinomas and 175 squamous carcinomas. All patients received radiotherapy as initial treatment and none received chemotherapy as a curative procedure. Eight patients received only palliative treatment. Twenty-seven patients were operated on because the response of the tumor to irradiation was partial or incomplete. One hundred and sixty patients received the full course of irradiation with a complete response. Among the latter, 100 patients were alive NED with a normal anal function with at least a 2-year follow-up. Local recurrences (n = 42) underwent salvage surgery in 50 p. 100 of the cases with a 3-year survival over 50 p. 100. Actuarial survival of the 195 patients was 68.5 p. 100 at 3 years and 58 p. 100 at 5 years. Survival was highly related to the initial size of the tumor and to the presence of positive inguinal nodes (p less than 0.0002). The histologic type was not related to the response to radiotherapy, nor to local recurrence or to survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Treatment of epidermoid anal canal cancer.

Between 1968 and 1979, 183 patients with invasive epidermoid cancer of the anal canal were treated at Institut Curie. There was 156 women, 27 men with a mean age of 67 +/- 11 years (range 40 to 85 years). The initial height of the tumor was less than 4 cm (65 patients), 4 to 6 cm (98 patients), and more than 6 cm (20 patients). All the patients received radiotherapy, either preoperatively or as curative procedure. Twenty-five patients received preoperative radiotherapy, and there was no residual tumor in 9 biopsies obtained at operation. Four local recurrences were observed. One hundred fifty-eight patients received curative radiotherapy, 115 of whom did not undergo operation. Eighty were alive with no evidence of disease and good anal function with a minimum of 3 years follow-up. We observed 15 local recurrences, 4 inguinal recurrences, and 8 visceral metastases. In addition, eight patients initially had such a big tumor that radiotherapy was only a palliative procedure. Forty-three patients required a surgical procedure after this curative radiotherapy. Colostomy (12 patients) or abdominoperineal amputation (25 patients) was required for local recurrence and colostomy was required for necrosis related to radiotherapy. Five year survival was 59 percent. The survival was related to the size of the tumor (p less than 0.0001). The likelihood of retaining normal anal function with local control of the tumor was also closely related to the initial size of the tumor.

Adult↗

Synthesis, receptor binding, and target-tissue uptake of carbon-11 labeled carbamate derivatives of estradiol and hexestrol.

The reaction of ethyl chloroformate with amino compounds has been evaluated as a simple route to carbon-11 labeling of steroid hormone-receptor-based imaging agents. Both a 17 beta-amino analogue of estradiol and an aminoethyl derivative of the nonsteroidal estrogen hexestrol with potential affinity for the estrogen receptor were studied. The unlabeled carbamate derivatives of the amino estrogens were prepared by standard methods, and the 11C-labeled analogues were synthesized from [11C]ethyl chloroformate, generated by purging ethanol with [11C]phosgene. Both carbamates showed weak in vitro binding affinity for the estrogen receptor, and only the 11C-labeled hexestrol exhibited a small but significant estrogen-responsive uterus uptake in immature rats.

Animals↗