Le testicule foetal est-il en danger ?

On assiste depuis les dernières décennies à une augmentation des anomalies de la différenciation de l’appareil génital mâle (hypospadias, cryptorchidisme) et du cancer du testicule, ainsi qu’à une diminution quantitative et qualitative de la production de spermatozoïdes. Des études épidémiologiques ont mis en relation ces altérations avec des modifications de l’environnement, et notamment avec l’exposition croissante à des molécules agonistes des oestrogènes ou antagonistes des androgènes. Des données cliniques et expérimentales laissent penser que ces xéno-oestrogènes agiraient pendant la vie foetale et néonatale en induisant des anomalies du développement testiculaire, responsables des altérations observées chez l’adulte. Nous avons effectivement démontré que les oestrogènes endogènes inhibent physiologiquement le développement du testicule foetal.Estrogens are classically known to play a major role in female reproduction, but there is now compelling evidence that they may also be involved in the regulation of male reproductive function. In humans, a decrease in sperm count and an increase in the incidences of testicular cancer, cryptorchidism and hypospadia have been observed in many countries over the last 50 years. Male reproductive alterations were also observed in wildlife. Such male reproductive disorders have been attributed to the increase in concentration of xenobiotics, and of xenoestrogens in particular, in the environment and in food. Epidemiological, clinical and experimental studies have suggested that excessive exposure to estrogens during fetal/neonatal life can lead to reproductive disorders in adulthood. Using an in vitro model, we showed that estrogens directly affected the development of the fetal testis. Lastly, we clearly demonstrated that the fetal and neonatal testis is very sensitive to estrogens since the invalidation of estrogen receptor α leads to an increase of steroidogenesis and the invalidation of estrogen receptor β enhances the development of the germ cell lineage in the male

Milk Microbiota: What Are We Exactly Talking About?

The development of powerful sequencing techniques has allowed, albeit with some biases, the identification and inventory of complex microbial communities that inhabit different body sites or body fluids, some of which were previously considered sterile. Notably, milk is now considered to host a complex microbial community with great diversity. Milk microbiota is now well documented in various hosts. Based on the growing literature on this microbial community, we address here the question of what milk microbiota is. We summarize and compare the microbial composition of milk in humans and in ruminants and address the existence of a putative core milk microbiota. We discuss the factors that contribute to shape the milk microbiota or affect its composition, including host and environmental factors as well as methodological factors, such as the sampling and sequencing techniques, which likely introduce distortion in milk microbiota analysis. The roles that milk microbiota are likely to play in the mother and offspring physiology and health are presented together with recent data on the hypothesis of an enteromammary pathway. At last, this fascinating field raises a series of questions, which are listed and commented here and which open new research avenues

Influence of the Temperature and the Genotype of the HSP90AA1 Gene over Sperm Chromatin Stability in Manchega Rams

The present study addresses the effect of heat stress on males' reproduction ability. For that, we have evaluated the sperm DNA fragmentation (DFI) by SCSA of ejaculates incubated at 37°C during 0, 24 and 48 hours after its collection, as a way to mimic the temperature circumstances to which spermatozoa will be subject to in the ewe uterus. The effects of temperature and temperature-humidity index (THI) from day 60 prior collection to the date of semen collection on DFI were examined. To better understand the causes determining the sensitivity of spermatozoa to heat, this study was conducted in 60 males with alternative genotypes for the SNP G/C−660 of the HSP90AA1 promoter, which encode for the Hsp90α protein. The Hsp90α protein predominates in the brain and testis, and its role in spermatogenesis has been described in several species. Ridge regression analyses showed that days 29 to 35 and 7 to 14 before sperm collection (bsc) were the most critical regarding the effect of heat stress over DFI values. Mixed model analyses revealed that DFI increases over a threshold of 30°C for maximum temperature and 22 for THI at days 29 to 35 and 7 to 14 bsc only in animals carrying the GG−660 genotype. The period 29–35 bsc coincide with the meiosis I process for which the effect of the Hsp90α has been described in mice. The period 7–14 bsc may correspond with later stages of the meiosis II and early stages of epididymal maturation in which the replacement of histones by protamines occurs. Because of GG−660 genotype has been associated to lower levels of HSP90AA1 expression, suboptimal amounts of HSP90AA1 mRNA in GG−660 animals under heat stress conditions make spermatozoa DNA more susceptible to be fragmented. Thus, selecting against the GG−660 genotype could decrease the DNA fragmentation and spermatozoa thermal susceptibility in the heat season, and its putative subsequent fertility gainsPublishe

La géographie des équipements et services en faveur des personnes âgées en France

The geography of equipments and services in favour of elderly people in France. There are deep regional differences in the facilities available to older people. Among the French regions, there are 140 institution-beds for 1000 people aged 75 plus on the average. Some regions (Pays de la Loire, Normandy) have more than 180 while others have only 100 or less (Corsica, Provence-Alpes-Côte d'Azur, Languedoc-Roussillon). 4,6% of retired people receive home-help (5,9% in Midi- Pyrénées, 3,2% in Provence Côte d'Azur). 5,8 in 1000 people aged 75 or more have home-care but the comparable figures in Britanny are 13%o and none in Corsica.II existe de profondes disparités régionales dans les équipements destinés aux personnes âgées. Si l'on compte en moyenne 140 lits d'hébergement collectif pour 1000 personnes âgées de 75 ans et plus, les Pays de la Loire, la Basse et la Haute-Normandie en possèdent plus de 180 tandis que la Corse, la région Provence- Alpes-Côte d'Azur et le Languedoc-Roussillon en ont 100 ou moins. 4,6 °/o des prestataires du régime général bénéficient d'une aide- ménagère. Mais ce sont 5,9 % de ceux du Midi-Pyrénées et 3,2 % de ceux de la Provence- Alpes-Côte d'Azur. Les services de soins à domicile touchent en moyenne 5,8%o des personnes âgées de 75 ans et plus, 13%o des habitants de la Bretagne, et aucun Corse.Delbès Christiane. La géographie des équipements et services en faveur des personnes âgées en France. In: Espace, populations, sociétés, 1987-1. Personnes âgées et vieillissement - Elderly people and ageing - Londres, juillet 1986. pp. 249-256

La famille des salariés du secteur privé à la veille de la retraite. II. Les relations familiales

Delbes Christiane. — The families wage earners to the private sector on the eve of retirement. II. Family relations. The result highlighted throughout our study demonstrate the persistence of many links between those surveyed and the members of their family who no longer live under the same roof. Visits are frequent : two-thirds of those surveyed see at least one of their children each week, ever 60 % see their grandchildren and a little over one third their parents whilst they are still alive. Such visits often provide the occasion for sharing a meal and exchanging services. These meetings, however, become very much less frequent when more distant relations including collaterals are concerned. Most of those surveyed state they all their expectations of family life had been fulfilled. Men appear more satisfied than women : 77,6 % were satisfied as against 59,4 %. Some of the differences noted result from the structure of the sample. The proportion of those surveyed living in couples in lower among women, and married respondents were more often satisfied than others. If attention is confined to the satisfaction provided by children, the situation is reversed : women, display a totally positive attitude more often than men.Delbes Christiane. — La famille des salariés du secteur privé à la veille de la retraite. II. Les relations familiales. Les résultats dégagés tout au long de notre étude montrent la persistance de nombreux liens entre les enquêtes et les membres de leur famille n'habitant plus sous le même toit. Les visites sont fréquentes : deux tiers des enquêtes voient au moins un de leurs enfants chaque semaine, plus de 60% un de leurs petits-enfants, un peu plus du tiers leurs parents lorsqu'ils sont encore vivants. C'est souvent l'occasion de partager un repas et aussi d'échanger de nombreux services. Mais, ces rencontres se raréfient très nettement dès que nous quittons la lignée directe pour nous intéresser à la famille plus lointaine y compris les collatéraux. Dans une optique plus qualitative, la majorité des enquêtes annoncent avoir reçu de la vie familiale tout ce qu'ils en attendaient. Les hommes se montrent plus comblés que les femmes: 77,6% de satisfaits contre 59,4%. Une partie, mais une partie seulement, des différences constatées tient à la structure de l'échantillon. La proportion des enquêtes vivant en couple est plus faible chez les femmes, or les enquêtes mariés sont plus fréquemment satisfaits que les autres. Si l'on ne s'intéresse plus à la vie familiale en général, mais à la satisfaction apportée par les enfants, la situation se retourne : les femmes, plus souvent que les hommes, manifestent une attitude totalement positive.Delbes Christiane. — La familia de los asalariados del sector privado en visperas de jubilar. II. Las relaciones familiares. Los resultados obtenidos a lo largo de este estudio muestran la persistencia de numerosas relaciones familiares entre los entrevistados y los miembros de su familia que ya no viven bajo el mismo techo. Las visitas son frecuentes : dos tercios de los entrevistados ven рог lo menos a uno de sus hijos cada semana; mas de un 60% ven uno de sus nietos y un poco más de un tercio sus padres cuando estos viven todavia. A menudo es la ocasión de compartir una comida y también de intercambiar numerosos servicios. Pero, estos encuentros se hacen cada vez más raros desde que se abandona la linea de parentezco directa para considerar a los familiares más lejanos, incluyendo a los colaterales. En una optica más cualitativa, la mayor parte de los entrevistados declaran haber recibido de la familia todo lo que ellos esperaban. Los hombres se muestran más satisfechos que las mujeres : 77,6 % contra 59,4. Una parte, pero una parte solamente, de las diferencias encontradas se deben a la composición de la muestra. La proporciórt de los entrevistados que viven en parejas es menos frecuente entre las mujeres, pero los hombres casados aparecen con frecuencia más satisfechos que el resto. Si se toma en consideracion la satisfacción que proporcionan los hijos, sin considerar la vida familiar en general, la situation se invierte : las mujeres manifiestan una actitud totalmente positiva con más frecuencia que los hombres.Delbès Christiane. La famille des salariés du secteur privé à la veille de la retraite. II. Les relations familiales. In: Population, 38ᵉ année, n°6, 1983. pp. 959-974