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B Blondel

Publications and source records attributed to B Blondel.

At least 55 records · Page 3Linked to original sources
PubMed1999

Poliovirus induces apoptosis in the mouse central nervous system.

Poliovirus (PV) is the etiological agent of human paralytic poliomyelitis. Paralysis results from the destruction of motoneurons, a consequence of PV replication. However, the PV-induced process leading to the death of motoneurons is not well known. We investigated whether PV-induced central nervous system (CNS) injury is associated with apoptosis by using mice as animal models. Transgenic mice expressing the human PV receptor were infected intracerebrally with either the neurovirulent PV-1 Mahoney strain or a paralytogenic dose of the attenuated PV-1 Sabin strain. Nontransgenic mice were infected with a mouse-adapted PV-1 Mahoney mutant. DNA fragmentation was demonstrated in CNS tissue from paralyzed mice by visualization of DNA oligonucleosomal laddering and by enzyme-linked immunosorbent assay. Viral antigens and DNA fragmentation detected by the in situ terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end-labeling technique were colocalized in neurons of spinal cords from paralyzed mice. In addition, morphological changes characteristic of cells undergoing apoptosis were observed in motoneurons by electron microscopy. Thus, we show that PV multiplication and CNS injury during paralytic poliomyelitis are associated with apoptosis.

Animals↗
PubMed1998

Poor antenatal care in 20 French districts: risk factors and pregnancy outcome.

STUDY OBJECTIVE: Poor attendance to antenatal visits was studied to identify risk factors and to analyse the association with adverse pregnancy outcome. DESIGN: All poor attenders and a sample of good attenders were compared within three groups of women: women < 20 years, French women > or = 20 years, and foreigners > or = 20 years. SETTING: 20 French districts including 85,000 births from January to June 1993. SUBJECTS: 848 poor attenders and 759 good attenders. Poor attenders made fewer than four antenatal visits or began care during or after the sixth month. Good attenders made at least four visits and began care before the sixth month. MAIN RESULTS: 1.1% of the women were poor attenders. Risk factors for poor attendance were single status and lack of health insurance in the group under 20; young age, high parity, and single status in the French group aged over 20; and single status and lack of health insurance in the foreign group aged over 20. For poor attenders, the odds ratios for preterm delivery were 5.8 (95% CI: 3.2, 10.5) among French women and 3.3 (95% CI: 1.5, 7.4) among foreign women with health insurance. Poor attendance was not associated with poor pregnancy outcome in the group under 20, and among foreign women over 20 without health insurance, but both groups had high rates of preterm delivery and low birth weight. CONCLUSION: Lack of health insurance is an important barrier to health care during pregnancy. Poor antenatal care is an important risk factor for adverse pregnancy outcome among women who have easy access to health care services.

Adolescent↗
PubMed1998

Molecular aspects of poliovirus biology with a special focus on the interactions with nerve cells.

Poliovirus (PV), the pathogenic agent of paralytic poliomyelitis, is the prototype of the picornavirus family. Although paralytic poliomyelitis has been nearly totally eradicated in most industrialized countries, PV continues to be an important public health problem in many developing countries. Moreover, in industrialized countries, two current concerns are the occurrence, albeit at a very low frequency, of vaccine-associated paralytic poliomyelitis, due to the genetic instability of the attenuated oral PV strains in vaccines, and the emergence of a neuro-muscular pathology in many survivors of the acute disease, called the post-polio syndrome. PV has been targeted by the World Health Organization for world-wide eradication in the coming decade and continues to be the subject of intensive research. The advances made in the molecular biology of PV, taken together with the development of new animal and cell models, have permitted a new look at a key step in the pathogenesis of poliomyelitis, i.e. the interactions between PV and nerve cells. These aspects of PV biology are developed in this review according to three themes: (i) the PV host range; (ii) the molecular determinants of PV neurovirulence and attenuation; and (iii) the persistence of PV in nerve cells, which has proven to be an interesting new domain in the field of PV research.

Animals↗
PubMed1998

[Medical responsibility of midwives in public and private maternity units. Results of a survey of 11 French regions].

OBJECTIVE: To describe medical responsibilities of midwives in maternity units and to compare these responsibilities between categories of maternity units. METHOD: A mail survey was carried out in 1996 on a random sample of midwives. The analysis was based on 884 midwives providing antepartum, perpartum or postpartum care in public or private maternity units. RESULTS: For many procedures and decisions, medical responsibilities of midwives were more important in the public sector than in the private sector. Responsibilities were more extended in university hospitals than in other public hospitals. These differences were observed in the postnatal ward, in the antenatal ward, and for some specific tasks in the labor ward. In the private sector, responsibilities varied according to the status of the maternity unit: midwives performed fewer procedures in profit-based maternity units than in non-profit ones. CONCLUSION: The roles of midwives vary from one type of maternity unit to another, but differences are also observed within the same categories of units. Consensus on what are the medical responsibilities of midwives does not exist in a variety of situations, even with regard to the management of normal pregnancies and deliveries.

France↗
PubMed1997

Psychological consequences of having triplets: a 4-year follow-up study.

OBJECTIVE: To assess the mental health of mothers of triplets and the quality of relationship with the children 4 years after delivery. DESIGN: Prospective follow-up study from delivery, to 4 years. Assessments at home by a psychologist, using semistructured tape-recorded interviews. SETTING: One maternity hospital in Paris, France. PATIENT(S): Eleven consecutive mothers having delivered triplets between October 1988 and February 1990. All except one had conceived after infertility treatment. MAIN OUTCOME MEASURE(S): Evaluation of the mothers' emotional well-being and level of depression measured by the CES-D Scale (Center for Epidemiologic Studies-Depression Scale). Opinion of the mothers about the quality of the relationship with the children. RESULT(S): All mothers reported emotional distress at 4 years, mainly fatigue and stress. Four mothers had a high score of depression and used psychotropic medication. The relationship with the children and difficulties in coping with their aggressive behavior and conflicts were the main reason for psychological distress. Difficulties had not decreased since the previous assessment at 2 years. Four mothers spontaneously expressed regrets about having triplets. CONCLUSION(S): Patients undergoing infertility treatments should receive adequate information about the long-term psychological "cost" of a triplet birth. Infertility treatments should be adapted in order to decrease the risk of triplet pregnancies.

Adaptation, Psychological↗
PubMed1997

[Medical certificate of neonatal death].

A specific neonatal death certificate has been put into use in France since April 1997. It must be completed for any infants born alive and deceased between 0 and 27 days. Its content is presented together with the results of an evaluation of its use performed during a 3 month period in 1996. This certificate is aimed to improve the mortality statistics of the neonatal period, thus helping to better define the priorities in the medical care and prevention fields.

Cause of Death↗
PubMed1997

Psychological reactions after multifetal pregnancy reduction: a 2-year follow-up study.

This study had two objectives. Firstly we assessed the effects of multifetal pregnancy reduction on the mothers' emotional well-being and the relationship with the children during the 2 years following intervention. Secondly at 2 years we compared mothers who had a reduction with mothers who had not and had delivered triplets. The comparisons focused on the mothers' health and their relationship with the children. Women having had a reduction in two hospitals in Paris, between May 1992 and June 1993, were contacted just after intervention for a prospective study. In all, 18 women were included. At 1 and 2 years, 10 women participated. At 2 years, 10 additional women were included. The answers of these 20 mothers were compared to those of 11 consecutive mothers of 2 year old triplets, assessed by the same psychologist in a previous prospective study. Semi-structured interviews were conducted at home. The mothers' social characteristics, their parity, the children's condition at birth and 4 months were very similar between the reduction and triplet groups. One year after birth one-third of the women in the reduction group reported persistent depressive symptoms related to the reduction, mainly sadness and guilt. The others made medical and rational comments expressing no emotion. At 2 years all but two women seemed to have overcome the emotional pain associated with the reduction. The comparison with mothers of triplets indicated that the mothers' anxiety and depression, and difficult relationship with the children were less acute in the reduction group. These results presented some limitations, since a high number of women who miscarried or refused to participate in the follow-up were not assessed at 1 and 2 years. However, a majority of women who participated in the study 2 years after intervention seemed able to accept a multifetal pregnancy reduction to achieve parental goals.

Adult↗
PubMed1997

Persistent poliovirus infection in mouse motoneurons.

Poliovirus (PV) is the causal agent of paralytic poliomyelitis. Many survivors of the acute disease, after decades of clinical stability, develop new muscular symptoms called postpolio syndrome. It has been hypothesized that the persistence of PV in the spinal cord is involved in the etiology of this syndrome. To investigate the ability of PV to persist in the spinal cord after the onset of paralysis, we exploited a mouse model in which most animals inoculated with a mouse-adapted mutant survived after the onset of paralysis. Light microscopy and ultrastructural immunohistochemical studies and reverse transcription followed by nested PCR performed on spinal cord from paralyzed mice demonstrated that PV persisted in the mouse spinal cord for at least 12 months after the onset of paralysis. This mouse model provides a new tool for studying poliomyelitis evolution after the onset of paralysis.

Animals↗
PubMed1997

[Marital violence after birth].

OBJECTIVE: The purpose was to estimate the prevalence of marital violence during the year after childbirth in France. METHODS: a survey has been carried out in three maternity units among primipara and secondipara women in 1993-1994. The women were interviewed in the three days after the delivery and they received a postal questionnaire 5 and 12 months later. The analysis includes 706 women. RESULTS: the prevalence of marital violence during the 12 months after childbirth is equal to 4.1% (2.6%-5.6%). This percentage is higher among women living an unstable relationship with their partner or when the partner has not a job. These women who reported marital violence had a higher prevalence of previous miscarriage. They used more often psychotropic drugs and reported more often depressive symptoms than the other women. CONCLUSION: physicians may be helpful by listening and counseling these women who receive low emotional and social support.

Abortion, Spontaneous↗
PubMed1997

[The perinatal situation in France. Trends between 1981 and 1995].

OBJECTIVES: Assess the main indicators of health status and medical practice at delivery and to determine the feasibility of a routine national survey. POPULATION AND METHOD: A survey conducted in 1995 concerned all live births and stillbirths occurring within one week. The sample included 13,147 women in metropolitan France. The results were compared with those of earlier national perinatal surveys. RESULTS: Since 1981, the perinatal situation in France has shown a rise in maternal age at delivery, development of prenatal care (particularly the number of visits), and an increase in the number of procedures at delivery, notably induction. The preterm delivery calculated for all births has remained unchanged: 5.6% in 1981 and 5.9% in 1995, but the proportion of infants weighing less than 2500 g has increased from 5.2% to 6.2%. CONCLUSION: The 1995 national perinatal survey in France, based on all births during one week and involving minimal data collection has provided a representative sample of births and information well adapted to surveillance of the main health and medical practice parameters. This type of survey should become routine and serve as a basic element for epidemiological surveillance.

Adult↗
PubMed1996

Fetal heart rate monitoring by telephone during pregnancy--opinion of users and non-users of a new technology.

OBJECTIVE: To compare the opinions of obstetricians who currently use fetal heart rate monitoring (FHRM) by telephone with the opinions of obstetricians in favour of this technique, but who do not use it. STUDY DESIGN: A mail questionnaire was sent to the 612 members of a professional organization of obstetricians. The response rate was 76%. RESULTS: Fourteen percent of the respondents used FHRM by telephone and 43% did not use it, but were in favour of it. Compared with current users, non-users who were in favour of this technique indicated a wider range of clinical indications for monitoring, considered a greater proportion of women to be eligible, and wanted more frequent monitoring. These differences cannot be explained by the characteristics of the obstetricians (age, type of practice or attitude towards FHRM performed in maternity unit). CONCLUSION: Our survey shows a risk of extensive use of FHRM by telephone if this technique becomes easily accessible.

Female↗
PubMed1996

Mouse adaptation determinants of poliovirus type 1 enhance viral uncoating.

Most poliovirus (PV) strains, such as PV type 1/Mahoney, cannot infect the mouse central nervous system. We previously identified two determinants of mouse adaptation of PV type 1/Mahoney at positions 22 and 31 of the viral capsid proteins VP1 and VP2, respectively (T. Couderc, J. Hogle, H. Le Blay, F. Horaud, and B. Blondel, J. Virol. 67:3808-3817, 1993). These residues are located on the interior surface of the capsid. In an attempt to understand the molecular mechanisms of adaptation of PV to mice, we investigated the effects of these two determinants on the viral multiplication cycle in a human cell line. Both determinants enhanced receptor-mediated conformational changes leading to altered particles of 135S, one of the first steps of uncoating, and viral internalization. Furthermore, the residue at position 22 of VP1 appears to facilitate RNA release. These results strongly suggest that these determinants could also facilitate conformational changes mediated by the PV murine receptor and internalization in the mouse nerve cell, thus allowing PV to overcome its host range restriction. Moreover, both mouse adaptation determinants are responsible for defects in the assembly of virions in human cells and affect the thermostability of the viral particles. Thus, these mouse adaptation determinants appear to control the balance between the viral capsid plasticity needed for the conformational changes in the early steps of infection and the structural requirements which are involved in the assembly and the stability of virions.

Adaptation, Physiological↗