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J Bertin

Publications and source records attributed to J Bertin.

31 records · Page 2Linked to original sources
PubMed1993

Litigating reproductive and developmental health in the aftermath of UAW versus Johnson Controls.

In a major decision handed down last term (International Union [UAW] versus Johnson Controls, Inc.), the Supreme Court ruled that employment practices excluding fertile or pregnant women from the workplace because of alleged concerns for fetal health constitute illegal sex discrimination. We analyze the three opinions in the case and explain why the decision was an essential first step to promoting reproductive and developmental health in the workplace. Continued progress toward eliminating or reducing reproductive occupational risks will require comprehensive legal strategies involving private lawsuits, governmental regulation and enforcement actions, and new legislation designed to preserve the existing rights of workers and to obtain new and additional protections. Finally, we caution that, in designing such strategies, it will be important to avoid solutions that either shift responsibility for reproductive health to workers, rather than to employers, or that undermine other important legal rights.

Embryonic and Fetal Development↗
PubMed1992

Stalling by RNA polymerase II in the polyomavirus intergenic region is dependent on functional large T antigen.

RNA polymerase II encounters an elongation block and stalls in vivo during transcription of the late strand of polyomavirus DNA. In this study, we performed transcriptional run-on assays and localized the stalling site to a 164-nucleotide region (nt 11-175) that contains specific binding sites for polyomavirus large T antigen. The effect of large T antigen on elongation by RNA polymerase II through this region was examined in cells infected with a mutant polyomavirus (AT3-ts25E) which encodes a thermolabile large T antigen. Removal of functional large T antigen by shifting to the nonpermissive temperature (39 degrees) eliminated stalling by RNA polymerase in this region, although RNA polymerases transcribing other regions of the viral genome were unaffected. RNA polymerase resumed stalling when functional large T antigen was again allowed to accumulate by shifting back to the permissive temperature (32 degrees). We conclude that stalling by RNA polymerase II in vivo is dependent on the presence of functional large T antigen.

Animals↗
PubMed1988

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↗
PubMed1988

[Trophoblastic proteins].

Many studies conducted on human or animal placenta (chorion) suggest that the trophoblast is not only a passive filter between maternal and foetal blood flow, but is also endowed with complex functions. Factors of trophoblast origin involved in the mechanism of pregnancy recognition or maintenance of the progesterone environment required for the embryo survival, are reviewed. The main proteins involved in pregnancy are reported in table 1. Emphasis is laid on early signals of pregnancy which are of practical interest in human clinical medicine and animal husbandry. Among them, human chorionic gonadotropin (hCG), protein SP1 ("Schwangerschaftsprotein" 1) and some pregnancy-associated plasma proteins such as the PAPP A are very useful in the diagnosis of pregnancy, abortion, foetal abnormality or tumor in the human species. The presence of trophoblastin (presently studied in our laboratory) of a pregnancy-specific protein B and of early pregnancy factor (EPF) attest the establishment of pregnancy in domestic animals and in other mammals. The biological properties of some hormones such as placental lactogens (PL) or chorionic somatomammotropins (CS), human placental growth hormone (hPGH) contribute to a better understanding of the gestation function. Many other factors participate in the foetal development, for example, proliferin. Some proteins can display immunosuppressive properties or be responsible for the immune tolerance between the mother and the foetus. Although many placental proteins have already been defined, their biological functions have not yet been elucidated.

Animals↗
PubMed1987

Formation and maintenance of viroplasmic centers in Tipula iridescent virus-infected mosquito cells with deranged cytoskeletons.

We have examined the role of cytoskeletal elements with respect to the formation and maintenance of viroplasmic centers (VCs) in Tipula iridescent virus (TIV)-infected mosquito Aedes albopictus (C6/36) cells. Filamentous systems consisting of microtubules and microfilaments were detected by immunofluorescence microscopy. Inoculation of cells with TIV resulted in an alteration of microtubule and microfilament organization whether or not VCs developed. The formation of short arrays of microtubules induced by taxol or the depolymerization of microtubules by colchicine, as observed by immunofluorescence microscopy, had no apparent effect upon the development of VCs as detected by Hoechst staining and electron microscopy. The dissolution of the actin-containing filamentous system by cytochalasin B also had no effect upon development. We conclude from these results that microtubules and microfilaments are not involved in the formation or maintenance of VCs in TIV-infected A. albopictus (C6/36) cells.

Aedes↗
PubMed1980

[Reversed vein bypass for the femoro-popliteal axis (author's transl)].

One hundred and twenty nine saphenous femoro-popliteal or infra-popliteal bypass were realised in 125 patients, 55 for very short distance intermittent claudication, 32 for rest pain, 38 for distal gangrene. A one to seven years follow up allows to draw four conclusions: -- In spite of a 4% mortality and a decrease of permeability from 88% at one year to 58% at 5 years, one must consider that in most cases the limb was saved, pain disappeared and the patient was able to work again. -- In case of intermittent claudication, operative indication should be very limited to severe socio-professional disturbance. In contrast, one should not hesitate in case of limb threatening. -- If a thrombosis of the bypass occurs, the spontaneous prognosis is hazardous and the patient should immediately be sent back to the surgical team that first operated. -- Since preventive reoperations have better prognosis than curative reoperations, the authors emphazise the interest of a systematic research of late stenosis or aneurism at the bypass level or up or down in order to correct the trouble prior to acute ischemic complication.

Adult↗
PubMed1980

[Acute ischemic lesions in young women taking oral contraceptives. A report on 5 cases (author's transl)].

Severe ischemic lesions were observed in 5 cases among women aged between 35 and 43 years taking the contraceptive pill over a period of 4 years. Three of these patients developed sudden severe ischemia of the lower limbs after the unrecognized appearance of intermittent claudication for periods of from 2 to 10 months, and amputation was necessary after various ineffective treatments. Recovery occurred in the two other patients, one of whom developed ischemia in the upper limb, the other in the lower limb, who were treated at an early stage. The young age of these women and the absence of atheroma were factors that suggested that the oral contraceptives, taken for periods of from 6 months to 4 years, were at least partially responsible for the lesions, and this hypothesis was supported by the discovery of anti-ethinyl estradiol antibodies in the serum. This was probably not the only causative factor, however, as all the patients were smokers. These cases demonstrate the danger of associating smoking with the taking of oral contraceptives, that the latter should be discontinued when signs suggestive of peripheral arterial insufficiency appear, and that urgent thrombectomy should be conducted in cases of severe ischemic lesions.

Adult↗
PubMed1979

[Primary lymphoid sarcomas of the stomach. Ten cases (author's transl)].

These sarcomas fall within a precise definition and must be differentiated from gastrointestinal involvement in a haematological disorder. For certain histological forms (nodular forms), the prognosis is less bad than that of carcinomas. Pre-operative diagnosis, often difficult, must be established by large biopsies. The best results are likely to result from a combination of surgery and radiotherapy or of surgery and chemotherapy.

Adenocarcinoma↗
PubMed1977

[Value of total thyroidectomy with cervical dissection in the treatment of differentiated thyroid cancers].

Study of 52 cases of differentiated carcinoma of the thyroid treated by anatomically total thyroidectomy with block dissection of the cervical nodes indicated three amin findings: examination by puncture for cytological examination would have missed 8 micro-carcinomas; unilateral excistion would have bee inadequate in 12 patients; lymph node excision confined to detectable lymphadenopathies would have left neoplastic tissue in place in 8 cases. In the light of these advantages from an oncological standpoint, the complications of total thyroidectomy with bilateral block dissection are few and can be avoided in most cases.

Adolescent↗