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B Clavel

Publications and source records attributed to B Clavel.

48 records · Page 3Linked to original sources
PubMedDate not supplied

Choroidal responses in microgravity. (SLS-1, SLS-2 and hindlimb-suspension experiments).

Fluid and electrolyte shifts occurring during human spaceflight have been reported and investigated at the level of blood, cardiovascular and renal responses. Very few data were available concerning the cerebral fluid and electrolyte adaptation to microgravity, even in animal models. It is the reason why we developed several studies focused on the effects of spaceflight (SLS-1 and SLS-2 programs, carried on NASA STS 40 and 56 missions, which were 9- and 14-day flights, respectively), on structural and functional features of choroid plexuses, organs which secrete 70-90% of cerebrospinal fluid (CSF) and which are involved in brain homeostasis. Rats flown aboard space shuttles were sacrificed either in space (SLS-2 experiment, on flight day 13) or 4-8 hours after landing (SLS-1 and SLS-2 experiments). Quantitative autoradiography performed by microdensitometry and image analysis, showed that lateral and third ventricle choroid plexuses from rats flown for SLS-1 experiment demonstrated an increased number (about x 2) of binding sites to natriuretic peptides (which are known to be involved in mechanisms regulating CSF production). Using electron microscopy and immunocytochemistry, we studied the cellular response of choroid plexuses, which produce cerebrospinal fluid (CSF) in brain lateral, third and fourth ventricles. We demonstrated that spaceflight (SLS-2 experiment, inflight samples) induces changes in the choroidal cell structure (apical microvilli, kinocilia organization, vesicle accumulation) and protein distribution or expression (carbonic anhydrase II, water channels,...). These observations suggested a loss of choroidal cell polarity and a decrease in CSF secretion. Hindlimb-suspended rats displayed similar choroidal changes. All together, these results support the hypothesis of a modified CSF production in rats during long-term (9, 13 or 14 days) adaptations to microgravity.

Adaptation, Physiological↗
PubMedDate not supplied

[Anticancerous chemotherapy trial with duborimycin. Analysis of 151 cases].

Duborimycin is a new antimitotic agent approaching danorubicin and adriamycin in activity which has been tried on 151 patients suffering from cancer of different types, is an advanced local/regional stage and/or metastatic disease. It was administered intravenously every fortnight in a mean unit dose of 400 mg, and the duration of the treatment ranged from 2 to 52 weeks. Objective improvement was registered in 56 patients of the 135 cases in whcih the results were assessed (around 41.4% of cases). In 4 cases the regression of tumour volume was greater than 50% (one of these cases was in melanoma, the other a sarcoma) and in 2 cases regression was complete (a squamous cell carcinoma and an embryonal testicular tumour). The subjective effects were appreciable in 53 of the 115 cases which could be studied (46%) and above all in the refractory pain of bony secondaries from breast cancer (a favourable response in 78% of cases). Manifestations of intolerance/toxicity were of a minor nature on the haematologic side, that cardiologic ones relatively frequent (18% of treated cases) and occasionally serious (2 cases of asystole). Great care is therefore necessary in supervision of the treatment. However, the first results obtained by this line of approach, notably in chemo-resistant forms of tumour such as melanoma and sarcomas, utilizing the very strict criteria in one analysis encourage further study of duborimycin in cases of this sort (preferably in association and in accordance with protocols of comparative trials) so that its place in cancer chemotherapy may be more precisely defined.

Adenocarcinoma↗
PubMedDate not supplied

[Chemotherapy of soft tissues sarcomas. Summary of a decade and current trends].

The results of palliative chemotherapy applied to 123 patients with disseminated soft tissue sarcomas are reviewed with the recent literature data. With the exception of embryonal rhabdomyosarcomas of children, which are considered separately, the response of these tumors to chemotherapy is poor but not negligible. The association of several active drugs should permit substantial progress, especially in the initial stage of local treatment, when the number of disseminated cells is still reduced. A follow-up of controlled clinical studies must specify the modalities of multidisciplinary treatment in an effort to reduce regional recurrence or metastasis.

Adolescent↗