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Biomedical subjects

B Blondel

Publications and source records attributed to B Blondel.

At least 19 recordsLinked to original sources
PubMed1995

Cell clones cured of persistent poliovirus infection display selective permissivity to the wild-type poliovirus strain Mahoney and partial resistance to the attenuated Sabin 1 strain and Mahoney mutants.

We report the isolation and characterization of HEp-2c cell clones obtained after two successive persistent poliovirus (PV) infections. Once cured, some of the cell clones displayed selective permissivity toward the wild-type Mahoney strain and partial resistance to particular mutants of this strain, including the Sabin 1 strain. Two cell clones, CI 4 and CI 10, were studied in greater detail. The cytopathic effects of Mahoney infection were comparable in the cell clones and in HEp-2c cells. The cytopathic effects of infection by Sabin 1 or Mahoney mutants were greatly delayed in CI 4 and CI 10. In the genomic region encoding the capsid proteins, determinants involved in the resistance of the cell clones to the Mahoney mutants were localized in the amino-terminal part of VP1 (amino acids 22 and 43), the B-C loop of VP1 (amino acids 94-102), and the loop of VP3 connecting its amino-terminal to beta strand B (amino acid 60). These genomic regions are thought to be involved in the early steps of viral infection. Virus adsorption was slower and less efficient on CI 10 cells than on parental HEp-2c cells. Virus adsorption was faster on CI 4 than on HEp-2c cells, and at least as efficient, but there was less receptor-induced structural modification of the capsid, a step that is required for decapsidation. Furthermore, infection of CI 4 by a Mahoney mutant in which the B-C loop of VP1 has been deleted was affected in the later steps of infection. These results indicate that, in cells cured of persistent PV infection, poliovirus multiplication was restricted at several stages and particularly at two steps of virus entry: adsorption and/or the uncoating transitions following adsorption onto the receptor.

Base Sequence↗
PubMed1995

[Usefulness of follow-up in pregnancies. Risk of pregnancies with not enough or no follow-up examinations].

The French system of antenatal care, based on financial incentive, recommends 7 antenatal visits for all pregnancies. Would fewer visits increase perinatal risk? The higher risk of low birthweight and perinatal mortality in women with little or no antenatal care is a well-known observation but data are certainly biased by socioeconomic and environmental conditions. In Western populations, for example, very high risk pregnancies are certainly under-represented in the little or no care comparison groups. Even if the effects of antenatal care may be underestimated, it is highly unlikely that extremely massive risks would be associated with few or no antenatal visits since even in the most favourable conditions, antenatal examinations cannot detect all the possible anomalies which can occur during pregnancy and available means of avoiding perinatal mortality are not perfect. The debate now focuses on optimal antenatal care. Are the 7 visits in France adequate? At present, are there risks of over-medicalization and excessive medical cost? Some answers to these questions may be forth coming from research projects. The perinatal plan, begun in France in 1994, will also provide recommendations for improving the quality of antenatal care.

Female↗
PubMed1995

Did preterm deliveries continue to decrease in France in the 1980s?

To study the trends in gestational age and birthweight in France, we compared data from three surveys that were based on representative samples of births in 10 French regions and were conducted in 1972, 1981 and 1988-89. Only single livebirths were considered in the analysis. The rate of preterm births decreased from 7.9% in 1972 to 5.8% in 1981 and 4.0% in 1988-89. The corresponding rates of children with a birthweight below 2500 g were 5.4, 4.3 and 4.7%. The mean birthweight of preterm babies born in 1988-89 was lower than the mean birthweight of those born in 1972 and 1981. The reduction in preterm births cannot be attributed to the improved accuracy of gestational age determination, but the general use of ultrasound may have played a major role in the apparent reduction of the mean birthweight of preterm babies.

Birth Weight↗
PubMed1995

[Psychological effects of embryonal reduction. From the decision making to 4 months after delivery].

The psychological effect of reducing the number of embryons was studied prospectively in two Paris hospitals. All women who had multifetal pregnancy reduction (n = 18) were contacted for interviews just after the operation, during pregnancy, and four months after delivery. The decision to reduce the number of embryons was painful and led to a guilty feeling. After operation, nearly one-half of the women suffered psychologically. To justify their decision, and contain their emotions, the women spoke of the problems related to having triplets and, most importantly, the medical arguements explained by the physician. Medical counselling is thus essential to help this couples at the time of the operation. The pregnancy period is almost always a period of calm for these women. Nevertheless, four months after delivery, 5 women expressed a psychological malaise related to the reduction, and 2 women refused to continue the study because they did not want to revive their suffering. This study shows that psychological problems are of major importance after multifetal pregnancy reduction and can occur several months after delivery. These negative conclusions should however be examined in light of the consequences if reduction had not been performed.

Adult↗
PubMed1994

Randomised controlled trial of routine cervical examinations in pregnancy. European Community Collaborative Study Group on Prenatal Screening.

Preterm delivery is strongly associated with neonatal mortality and morbidity. In some European countries, cervical examinations are used routinely during pregnancy to identify women at risk of preterm delivery. We sought to evaluate the efficacy and secondary effects of these routine cervical examinations. We did a randomised controlled trial in seven European countries, comparing two policies--namely, an attempt to do a cervical examination at every prenatal visit (2803 women) and avoidance of cervical examination if possible (2799). The median number of cervical examinations was 6 in the experimental group and 1 in the controls. There were 6.7% preterm (< 37 weeks) deliveries in the experimental group and 6.4% in the control group (risk ratio 1.05 [95% confidence interval 0.85-1.29]; non-significant). The low birthweight rate was 6.6% in the experimental group and 7.7% in the controls (non-significant). Premature rupture of membranes was not significantly more frequent in the experimental group (27.1% vs 26.5%). Our findings do not support the routine use of cervical examinations during pregnancy.

Adult↗
PubMed1994

Substitutions in the capsids of poliovirus mutants selected in human neuroblastoma cells confer on the Mahoney type 1 strain a phenotype neurovirulent in mice.

Poliovirus (PV) type 1 mutants selected in human neuroblastoma cells persistently infected (PVpi) with the wild-type Mahoney strain exhibited a mouse-neurovirulent phenotype. Four of the five substitutions present in the capsid proteins of a PVpi were demonstrated to extend the host range of the Mahoney strain to mice. These new mouse-neurovirulent determinants were located in the three-dimensional structure of the viral capsid; two of them (residues 142 of VP2 and 60 of VP3) were located in loops exposed at the surface of the protein shell, whereas the other two (residues 43 of VP1 and 62 of VP4) were located on the inside of the capsid. VP1 residue 43 and VP2 residue 142 substitutions were also selected in a PVpi derived from the attenuated Sabin strain. We suggest that the selective pressure of human neuroblastoma cell factor(s) involved in early steps of PV multiplication could be responsible for the arising of amino acid substitutions which confer adaptation to the mouse central nervous system to PV.

Amino Acid Sequence↗
PubMed1994

International infant mortality rates: bias from reporting differences.

International infant mortality statistics have caused concern in the United States, since the US ranking relative to other developed countries has declined since World War II. This paper suggests that there may be international differences in reporting of very-low-birthweight infants and perinatal deaths and that such reporting differences bias comparisons of national perinatal and infant mortality rates. Efforts must be made to adopt standard conventions for the inclusion of small, early infants and fetal deaths in rate calculations.

Bias↗
PubMed1994

[Two-year follow-up cohort studies on triplets: development of children and mother-child relationship].

BACKGROUND: The number of triplets births has increased during the last 15 years. The psychomotor development of triplets, problems concerning long-term relationships between the mother and her children and between the children themselves are still incompletely studied. PATIENTS AND METHODS: Eleven families with triplets, consecutively born at the Clinique Baudelocque, were assessed at home for 2 years by the same psychologist. IQ was measured in each child at the age of 2 years using the Brunet-Lezine test. At this age, all mothers completed the Symptom-Check List allowing to assess eventual relationship difficulties between the mother and their children. RESULTS: The psychomotor development of the children (IQ = 100) was similar to the mean score in the general population. The mother reported great physical fatigue during the first year after birth and psychological difficulties during the second year. They mentioned behavioral problems and difficult relationships among the triplets. They complained of not being able to fulfill the children's demands. In four families, more severe difficulties, potentially damaging the psychological well-being of the children, required an intervention during the survey. CONCLUSIONS: Improved and prolonged help to families with triplets is necessary, requiring the participation of pediatricians, nurses, psychologists, social workers and specialized people.

Child Development↗
PubMed1994

[Follow-up of mothers of triplets 2 years after delivery. Results of a longitudinal study].

The aim of the study was to assess the health of mothers of triplets, two years after delivery. As part of a longitudinal study, 11 mothers having delivered consecutively in clinique Baudelocque were interviewed at home. They reported considerable fatigue and stress. Four women suffered with anxiety and depressive symptoms and three of them used psychotropic medication. Considering the possible consequences of maternal depression upon the child development, one third of the children in the study are particularly at risk. These results showed that the difficulties experienced by mothers of triplets persisted and remained important even under favourable medical and social circumstances.

Child Development↗
PubMed1993

Poor antenatal care and pregnancy outcome.

OBJECTIVES: To characterize women receiving poor antenatal care and assess their perinatal risk. DESIGN: Computerized data. SETTING: Public hospital setting Paris (1987-1990). Comparison with representative sample in Ile-de-France region (n = 6423). METHODS: Poor attenders with less than 3 visits (n = 210) were compared with good attenders with 3 visits or more (n = 5631). RESULTS: Poor attenders were younger and had higher rates of perinatal mortality (4.7%), preterm delivery (Odds ratio 5.2:4.3-6.3) and low birth weight (Odds ratio 4.6:3.7-5.6). CONCLUSION: Women with poor antenatal care have a greater risk for adverse pregnancy outcome. This risk cannot be attributed to unfavourable living conditions only.

Adult↗
PubMed1992

Home uterine activity monitoring in France: a randomized, controlled trial.

OBJECTIVES: We assessed the effectiveness of ambulatory tocodynamometry in reducing the preterm delivery rate in women at risk of preterm delivery such as women with risk factors and women previously hospitalized and discharged. STUDY DESIGN: In four public maternity units these women were randomly allocated to two groups: 84 had home uterine activity monitoring and daily midwife contact and 84 were given the standard care for high-risk women, which generally includes home visits by community midwives. RESULTS: The proportion of deliveries before 37 weeks' gestation was slightly higher in the monitored group than in the control group (32% vs 22%). The corresponding odds ratio was 1.7 (95% confidence interval: 0.9 to 3.5). CONCLUSION: Although the sample was small, these results suggest that home uterine activity monitoring was probably not beneficial to the population studied, or at least that any benefit would have been too small to justify extending this monitoring in this high-risk population.

Cardiotocography↗
PubMed1992

Assessment at 1 year of the psychological consequences of having triplets.

The purpose of this study was to assess the psychological difficulties encountered by mothers 1 year after the birth of triplets. Twelve mothers entered the study having delivered triplets in a public hospital in Paris. Nine pregnancies had been initiated after in-vitro fertilization (IVF) or gamete intra-Fallopian transfer (GIFT), two after ovarian stimulation and one was spontaneous. The method consisted of tape-recorded semi-structured interviews at the mothers' homes. At 1 year, a majority of mothers reported considerable fatigue and stress. In most cases, home help was no longer provided by social services or by relatives. A majority suffered from social isolation and had difficulties in going out because of a lack of help, and inquisitive looks and questions from other people. Most mothers said that having triplets placed a strain on the marital relationship. The relationship with the children was often disturbed. Mothers reported that it was difficult to give adequate attention to the three children at the same time. Most of them tended to become emotionally detached. Eight mothers expressed psychological difficulties and three of them were treated for depression. Families with triplets should be provided with increased help, special attention, counselling and support, either at home, in clubs or in special clinics.

Emotions↗
PubMed1992

Home visits for pregnancy complications and management of antenatal care: an overview of three randomized controlled trials.

OBJECTIVE: To examine whether a policy of home visits reduces the amount of antenatal care provided by hospital maternity units. DESIGN: A meta-analysis of three randomized controlled trials. SETTING: 9 maternity units in France. SUBJECTS: 1410 women with pregnancy complications. INTERVENTION: 1 or 2 home visits a week by a midwife. MAIN OUTCOME MEASURES: Admission rate and length of stay in hospital. RESULTS: The home-visiting system did not affect the hospital admission rate (typical odds ratio = 0.9; 95% CI = 0.7-1.2). In each trial, the length of hospital stay did not differ between the intervention and the control groups. CONCLUSIONS: The home-visiting system did not greatly alter the practice of antenatal hospital admission in the maternity units studied. The results question the way the health services were used and suggest that a better integration of hospital and home services is needed to make a more rational use of health care resources.

Female↗
PubMed1991

Comparison of vaginal examination findings in two antenatal clinics.

Findings of routine vaginal examinations during pregnancy were compared in two teaching hospitals located in the same area of Paris. We selected 2943 women who had had at least one antenatal visit between 29 and 31 weeks of gestation. Large differences in the frequency of maturation signs were observed between the two hospitals for mid-position, soft consistency and expanded lower uterine segment, although the higher frequency of each sign was not found in the same hospital. No difference was observed for dilatation of the internal os. A better reliability in assessing dilatation than other signs of maturation may explain our results and the role of dilatation in the prediction of preterm delivery.

Adult↗
PubMed1991

An indicator of adverse pregnancy outcome in France: not receiving maternity benefits.

STUDY OBJECTIVE: The aim was to compare the social characteristics, the pregnancy outcome, and the antenatal care of women in France who did not receive maternity benefits to women who did. These benefits (860 FF, approx 86 pounds per month) are given to every pregnant woman, starting in the second trimester. Payments are made on the condition that at least three antenatal visits are made, the first being before the end of the first trimester. DESIGN: The study involved a random sample of women who were interviewed after delivery during their stay in hospital. Data on pregnancy outcome were collected from medical records. SETTING: The study was carried out in four public maternity units in different regions of France. PARTICIPANTS: 1692 women were included in the analysis (86.8% of the selected sample). Of 257 exclusions, 40 had multiple pregnancies, 189 had missing data, and 28 did not answer the question concerning maternity benefits. MEASUREMENTS AND MAIN RESULTS: 4.3% of the women did not receive any maternity benefits. These women lived in poorer social conditions than the women who received the benefits. They had a higher preterm delivery rate, after controlling for risk factors in a logistic regression. Women without maternity benefits were characterised by a lower level of care, yet the majority began their antenatal care during the first trimester or had more than six visits. CONCLUSIONS: Not receiving maternity benefits during pregnancy is an index of an underprivileged situation and a risk factor for pregnancy outcome.

Age Factors↗