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Biomedical subjects

P Boyer

Publications and source records attributed to P Boyer.

At least 91 records · Page 5Linked to original sources
PubMed1993

Impaired response of polycythemic mice to erythropoietin induced by protein starvation imposed after hormone administration.

The present study was performed to determine the stage of the erythropoietic pathway which is affected by starvation or protein deprivation and whose manifestation is a depressed response to exogenous erythropoietin (EPO). The response to recombinant human EPO was measured in post-hypoxic polycythemic mice by determination of 59Fe uptake into red cells, spleen and femur and/or erythroid colony forming units (CFU-E) and erythroid precursor cell concentrations in femoral marrow. Experimental mice were either starved or fed one of seven different diets whose protein (casein) content ranged from 0 to 20%. All diets were isocaloric. The response of mice maintained on the standard diet (Purina Lab chow) was taken as the normal one. Starvation during the 48-hour period immediately before EPO injection had no effect on the response to the hormone. Starvation, and protein deprivation to a lesser extent, during the 48-hour period following EPO, on the other hand, significantly reduced the response. There was a progressive increase in the response as the casein content of the diet was increased. A normal response was observed when dietary casein concentration was 10%. These findings indicate that nutritional deprivation or dietary protein alterations during the period immediately following EPO injection in polycythemic mice can have detrimental effects on the erythroid response in a model in which nutritional deprivation was relatively short and acute. They also indicate that the subnormal response is not due to a decreased size of the erythroid progenitor pool available for differentiation but to deficient rates of differentiation of erythropoietic units.

Animals↗
PubMed1993

Failed oocyte retrieval in in-vitro fertilization with documented positive serum beta-human chorionic gonadotrophin (HCG) concentration on day HCG+1.

No oocytes were obtained at ovum retrieval in a 33-year-old patient with secondary tubal infertility, whereas in a previous cycle nine oocytes were obtained under the same ovarian stimulation protocol as used in the studied cycle. Oocyte retrieval failed in spite of the correct administration of human chorionic gonadotrophin (HCG) as demonstrated by serum beta-HCG concentration (58.6 mIU/ml) on day HCG+1. However, it was shown that progesterone failed to rise even after the administration of exogenous HCG as the luteinizing hormone signal. Therefore, when ovum retrieval fails, the serum progesterone as well as beta-HCG concentrations may be useful to help identify the cause of this unusual event.

Adult↗
PubMed1993

Local medical treatment of interstitial pregnancy after in-vitro fertilization and embryo transfer (IVF-ET): two case reports.

Two cases of interstitial pregnancy (one singleton, one heterotopic twins) were confirmed 31 and 34 days after in-vitro fertilization. Serum human chorionic gonadotrophin concentrations were 35,000 and 86,000 mlU/ml, respectively. They were treated conservatively with transvaginal ultrasonically guided intra-ovular injection of either methotrexate in the singleton pregnancy, or potassium chloride into the ectopic sac of the heterotopic twins. No complications were observed. The intra-uterine pregnancy continued and the patient delivered a 3350 g healthy baby at 39 weeks.

Abortion, Therapeutic↗
PubMed1993

Cervical nucleolysis: indications, technique, results. 190 patients.

For many years now percutaneous techniques have proved effective in the curative treatment of lumbar disc herniation, mostly in young subjects. This technique, however, is seldom indicated, let alone performed, in the cervical spine for a variety of reasons: a) the neck contains several closely arranged structures such as the vasculo-nervous bundles, the airway-digestive tract and the cervical spine around the spinal cord; b) the disc is approached by the anterior route, in contrast with the lumbo-sacral spine where the approach is posterolateral; c) the manufacturers insist on restrictions in the use of chymopapain in view of the potential risk of spinal cord damage, either by possible breaks in the meninges of by accidental diffusion of the enzyme into perimedullary epidural structures which support a particularly developed venous plexus; d) legal protection may be denied to operators who perform cervical chemonucleolysis, since the product has not yet been officially authorized, in France and perhaps elsewhere*, for treatment of cervical disc herniation. Several years of experience in the practice of cervical nucleolysis have convinced the authors that this method is remarkably effective and can be used in the treatment of cervicobrachial neuralgia (CBN) occurring in young subjects. Radiculalgia is essentially due to a disc fragment being positioned within the vertebral canal or a foramen, thereby compressing the nerve roots. During several years microsurgery of the disc has been effective in the treatment of refractory radiculalgia, and to compete with this procedure familiar to neurosurgeons cervical nucleolysis must convincingly demonstrate that its therapeutic value is at least as good as that of surgery. Finally, the vast majority of cervical disc herniations is made up of free disc fragments located within the meshes of the posterior longitudinal ligament of the spine (transligamentous fragment). Cervical nucleolysis was introduced in France by Bonafe and Lazorthes made enthusiastic by their first studies, and the idea of this procedure, developed by a radio-neurosurgical team, has gradually been gaining ground. The decision to intervene is made when the radiculalgia is recurrent or resistant to a well-conducted medical treatment of several weeks duration. Therefore all disc herniations that would have been treated surgically can be treated by injection of an enzyme. This point is very important, and in fact the well-codified and effective surgical procedure has progressively been abandoned by the operators, in view of the simplicity of nucleolysis and the rapid pain relief it procures.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1992

A survey of zidovudine use in pregnant women with human immunodeficiency virus infection.

BACKGROUND AND METHODS: The expanding indications for zidovudine treatment make it important to elucidate the safety and toxicity of this drug for pregnant women and their fetuses. We asked pediatricians and obstetricians at the AIDS (acquired immunodeficiency syndrome) Clinical Trials Units to report information about pregnant women infected with the human immunodeficiency virus (HIV) who were continuing their pregnancies and had received, or were receiving, zidovudine during gestation. RESULTS: Reports of 43 women were received from 17 institutions. Doses of zidovudine ranged from 300 to 1200 mg per day, and 24 women took the drug for at least two trimesters. There were two reported instances of maternal toxicity (one gastrointestinal and one hematologic). No teratogenic abnormalities occurred in the 12 infants with first-trimester exposure to zidovudine. All the infants, including two sets of twins, were born alive. The 38 singleton infants born at term for whom birth weights were reported had a mean birth weight of 3287 +/- 670 g; two cases of intrauterine growth retardation were reported among the infants delivered at term. Hemoglobin values, which were available for 31 newborns, ranged from 7.0 to 12.4 mmol per liter (11.2 to 20 g per deciliter); 3 of the 7 newborns with hemoglobin values of less than 8.4 mmol per liter (13.5 g per deciliter) were born prematurely. CONCLUSIONS: Zidovudine was well tolerated by the pregnant women and was apparently not associated with malformations in the newborns, premature birth, or fetal distress. No pattern of hematologic toxicity was observed in the newborns, but the anemia and growth retardation seen in a minority of the infants could, in part, have resulted from their mothers' treatment with zidovudine.

Abnormalities, Drug-Induced↗
PubMed1992

Teratogenic Agent Information Centre: fifteen years of counseling and pregnancy follow-up.

The Teratogenic Agent Information Centre was set up 15 years ago in response to a growing demand from a medical profession struggling to cope with the problem of teratogenic risk. Our goal was to provide information on the real nature of the risk and to monitor all at-risk pregnancies so as to obtain data in a field where there are still, unfortunately, many gaps in our knowledge. The results of these 15 years have been most encouraging, in that physicians have been provided with specialized information and the follow-up of gestations had provided considerable clinical data, which has contributed to advancing our understanding in this domain.

Counseling↗
PubMed1991

Early memories as expressions of relationship paradigms: a preliminary investigation.

Earliest childhood memories (EMs) have been utilized as expressions of relationship paradigms, but few empirical studies have been conducted. This study outlines the construction and development of an EM relationship scoring system and scale utilizing nonclinical and clinical samples. It was hypothesized that relationship episodes could be reliably coded using EMs and that they would demonstrate convergent validity with measures of attachment style (Separation-Individuation Test of Adolescence), mood (Profile of Mood States), and clinical symptomatology (Symptom Checklist 90-revised [SCL-90-R] and the Minnesota Multiphasic Personality Inventory [MMPI]). The hypotheses received broad support. Findings indicate that relationship episodes may be reliably coded from EMs. Associations between individual EM variables, the EM relationship scale, and objective measures suggest that the quality of relationships expressed in EMs is associated with degree of general maladjustment. Suggestions for further research are discussed.

Adult↗
PubMed1990

Therapeutic target for cognition enhancers: diagnosis and clinical phenomenology.

Uncertainty concerning therapeutic targets has probably retarded the development of cognition-enhancing drugs. While enhancement of normal cognitive function may be a legitimate goal it is unlikely that drugs developed without a clear clinical indication will ever be approved by regulatory authorities. Normal aging as a target would also appear to be excluded. The main debate is whether drugs should be developed for specific disease states (e.g., Alzheimer's), particular syndromes (e.g., AAMI) or for treating symptoms (e.g., memory deficits). Although targeting disease states appears the least problematic, it would be difficult to include many potentially treatable patients in such studies. In this respect, the status of AAMI is still the subject of much debate. In any case, it is important that trial populations be as homogeneous as possible, with clear diagnostic criteria (e.g., defined memory impairment, Hachinski score, CT scans) and that patients be moderately to severely affected.

Aging↗
PubMed1990

Retrograde tubal transfer of human embryos.

This preliminary study was designed to evaluate retrograde cannulation of the Fallopian tubes up to the isthmo-interstitial junction using the new technique of tubal embryo stage transfer (TEST). Follicular aspiration was performed under the guidance of a vaginal ultrasound probe in 51 women treated with GnRH + HMG. The oocytes retrieved were inseminated in vitro with 50,000 motile spermatozoa and kept in Menezo B2 medium without serum, at 37 degrees C, in an atmosphere of air + 5% CO2. The eggs were checked 24 and 36 h after insemination. No fertilization occurred in 23 patients. Cleaved embryos were obtained in the 28 other patients. One to seven embryos at the 2-4-cell stage were transferred with the 'Baudelocque Black Catheter' (BBC) into one tube and spare embryos were frozen. Five pregnancies occurred after retrograde TEST, for a pregnancy rate of 9.8% per cycle and 17.9% per transfer. One patient has given birth to a normal full-term baby. One singleton and one twin pregnancy are ongoing (8 months in June 1989). The other two pregnancies were ectopic.

Adult↗
PubMed1989

Immunoreactive renin variations during fertile and infertile hyperstimulated cycles with in-vitro fertilization and embryo transfer or gamete intra-fallopian transfer.

The concentrations of prorenin (PR) and active renin (AR) were determined sequentially during ovarian hyperstimulated cycles for in-vitro fertilization-embryo transfer or gamete intra-Fallopian transfer. AR and PR increased during the early luteal phase and PR was highly correlated with the progesterone concentration. In fertile cycles, AR increased more rapidly after HCG injection and AR and PR levels were significantly higher during the late luteal phase. These results confirm the role of the renin angiotensin system in ovarian physiology.

Adult↗
PubMed1989

Salivary oestradiol in spontaneous and stimulated menstrual cycles.

The determination of steroids in saliva provides useful information in the clinical study of various endocrine functions, and salivary progesterone concentration has been widely used for assessing corpus luteum function during the spontaneous menstrual cycle and early pregnancy. However, the determination of oestradiol in saliva (SE2) has previously been found unsatisfactory. SE2 profiles and saliva/plasma E2 ratios were established (during the different periods of the menstrual cycle) by a highly sensitive radioimmunoassay method during normal menstrual cycle. During cycles hyperstimulated for in-vitro fertilization and embryo transfer, the SE2 pattern is similar to the corresponding profile in plasma with a peri-ovulatory oestradiol peak. There is a significant difference between fertile and non-fertile cycles with a higher saliva/plasma ratio in conception cycles.

Adult↗
PubMed1988

Review of treatment of symptomatic cerebral vasospasm with nimodipine.

A number of randomized studies have shown the efficacy of nimodipine, administered either orally or intravenously, for the prevention of vasospasm and its clinical consequences in patients with subarachnoid haemorrhage following rupture of an intracranial aneurysm. It remained to be proven that nimodipine could also act on already established vasospasm. This was the aim of a multicentre study carried out in France between 1984 and 1986. Of a total of 127 patients with known clinically and/or angiographically diagnosed vasospasm, 73 (group N) underwent intravenous treatment with nimodipine and 54 (group P) with placebo within 24 hours of the onset of vasospasm. There was shown to be a significant reduction in mortality and morbidity in group N (33%) compared with group P (52%). Where vasospasm was the sole determining factor (63% of all patients), the decrease in mortality and severe morbidity rate was even greater in group N (11%) compared with group P (31.5%). These results can be viewed as confirmation of the efficacy of nimodipine in treating the ischaemic consequences of established vasospasm.

Brain↗
PubMed1988

Ovarian stimulation for in-vitro fertilization combining administration of gonadotrophins and blockade of the pituitary with D-Trp6-LHRH microcapsules: pilot studies with two protocols.

In women undergoing in-vitro fertilization and embryo transfer (IVF-ET), a total of 408 IVF cycles were stimulated using human menopausal gonadotrophin (HMG) or pure follicle stimulating hormone (FSH) plus HMG in combination with a single injection of D-Trp6-LHRH microcapsules in order to enhance the ovarian response to gonadotrophins and to avoid spontaneous LH surges. Sixty-seven pregnancies were achieved. Two protocols were employed. In protocol 1 ('blocking protocol', n = 268), the pituitary was first inhibited with a full dose (3.75 mg) of D-Trp6-LHRH in microcapsules and ovarian stimulation was started after the hypogonadotrophic hypogonadal state was ascertained (E2 less than 50 pg/ml). In protocol 2 ('flare-up protocol', n = 140), the treatment with D-Trp6-LHRH microcapsules (half-dose = 1.80 mg) and the ovarian stimulation with gonadotrophins were started at the same time. Higher doses of gonadotrophins were needed (39.5 +/- 11.2 ampoules FSH and/or HMG) in protocol 1, in which the pituitary was blocked prior to and during the stimulation, than in protocol 2 (20 +/- 9 ampoules) where the exogenous gonadotrophin stimulation appeared to be augmented by the initial agonistic effect of the injection of D-Trp6-LHRH microcapsules. In patients with purely tubal infertility, under 38 years old and no male factor, the results obtained with protocols 1 and 2 were similar in terms of pregnancy rate per cycle or per embryo transfer: 22.6 versus 20.5% and 28.3 versus 27.4%, respectively. However, considering the cost benefit, 'flare-up' protocols appeared to be a better choice and could be recommended.

Adult↗
PubMed1988

Ovarian programming and GIFT.

The procedures used for programming and ovarian stimulation in GIFT are identical to those used for in-vitro fertilization. At the Baudelocque Hospital, the hypophyseal gonadal axis is suppressed by administering a gonadotrophin-releasing hormone analogue (Decapeptyl, D-Trp-6-LHRH). Programming for the week of GIFT is then possible by controlling three stages: the beginning of treatment, which is independent of the date of the patient's period, the duration of treatment, which has 5 days' maximum variation, and an end-point of suppressing the spontaneous LH surge.

Female↗