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The invasive mosquito Aedes japonicus japonicus (Theobald, 1901) settled in 2013 in the Alsace region, in the northeast of France. In this temperate area, some mosquito species use diapause to survive cold winter temperatures and thereby foster settlement and dispersal. This study reports diapause and its seasonality in a field population of Ae. japonicus in the northeast of France. For two years, eggs were collected from May to the beginning of November. They were most abundant in summer and became sparse in late October. Diapause eggs were determined by the presence of a fully developed embryo in unhatched eggs after repeated immersions. Our study showed effective diapause of Ae. japonicus in this part of France. At the start of the egg-laying period (week 20), we found up to 10% of eggs under diapause, and this rate reached 100% in October. The 50% cut-off of diapause incidence was determined by the end of summer, leading to an average calculated maternal critical photoperiod of 13 h 23 min. Interestingly, diapause was shown to occur in part of the eggs even at the earliest period of the two seasons, i.e. in May of each year. Even though we observed that the size of eggs was positively correlated with diapause incidence, morphology cannot be used as the unique predictive indicator of diapause status due to overlapping measurements between diapausing and non-diapausing eggs. This study provides new knowledge on diapause characterisation and invasive traits of Ae. japonicus.

Fleas are ectoparasites of various animals, including Homo sapiens Linnaeus, 1758 (Primates: Hominidae). Among the species relevant to the human health field, either due to their dermatopathological potential or because of their role as vectors of microorganisms responsible for infectious diseases, such as plague or murine typhus, are the human flea, oriental rat flea, closely related cat and dog fleas, and chigoe flea. However, other species can accidentally infest humans. We have herein reported two unusual cases of humans infested and bitten by Archaeopsylla erinacei, the hedgehog flea. This species has been identified using stereomicroscopy, on the base of key characteristics. Furthermore, a brief literature review has revealed that hedgehog fleas could carry human-infectious agents, such as Rickettsia felis Bouyer et al. 2001 (Rickettsiales: Rickettsiaceae) or Bartonella henselae Regnery et al.1992 (Rhizobiales: Bartonellaceae). Using molecular biology, we thus tested nine A. erinacei specimens taken from these patients, for several bacteria species commonly associated with hematophagous arthropods, implicated in human pathology. However, all our samples were proven negative. The role of A. erinacei in human epidemiology has never been evaluated to date. This report sought to remind us that these fleas can be accidental parasites in humans. In addition, recent findings pertaining to bacteria of medical interest that are present in these insects should be brought to the fore, given that the question of their role as vectors in human infections remains unanswered and deserves further investigation., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The initial representations of the profession and of proper care of student nurses beginning their training, will, throughout their course, come up against the reality of nursing practice. At the heart of the complexity of potentially intrusive care procedures and the relational approach in which they are players or witnesses, their practical work experience becomes a modelling tool for their career. This is facilitated when the teaching team structures the reflexive analysis through pedagogical approaches favouring expression and objectivity between peers.

This work, based on a matched case-control design, tests the assumption that centenarians were conceived by parents younger than the parents of individuals who had lifespan close to mean life duration. The centenarians are paired with controls of the same sex, born at the same place and at the same time in order to avoid traditional biases related to mortality peaks or secular trend of increase in life expectancy. The parental age at the time of the birth registration of 320 centenarians born in France between 1875 and 1890 and deceased between 1990 and 1999 is collected, as well as the one of 603 controls of the same sex whose births were recorded immediately before or after those of the future centenarians on the birth registers of the cities concerned. No difference is found between the parental age of parents of centenarians and of controls. In particular, no difference is found for females. Recent studies showed--from genealogical data--that the life expectancy of a female would be much reduced if her father was old at the time of her conception. Our study does not indicate a negative effect of a higher paternal age on the longevity of daughters.

We have studied the polymorphism of HLA-A, B, in 2 elderly populations (> or = 90 years) compared to a control series of 429 healthy unrelated individuals less advanced in age. The aged population issued from the CHRONOS cohort consisted of 336 centenarians without familial history of longevity, and 102 nonagenarians index cases randomly selected from families. Almost all individuals (310) were previously typed for HLA-DRB1. The increased allelic frequency of HLA DR11 was observed in familial nonagenarians (18.3%) compared to controls (10%) (p < .001) and to sporadic centenarians (11.8%). Concerning HLA Class I alleles, only rare alleles (A30, B70) remain significantly different from the controls after correction of the p value. No distortion of the Mendelian sharing of haplotypes was observed among sibling pairs of familial nonagenarians. A protective effect of the HLA-DR11 molecule itself, presenting adequately immunogenic-infectious peptides, is probable rather than genes in disequilibrium. Our study strongly supports the heterogeneity of longevity, the association of HLA-DR11 in its familial form in aged populations.

It is possible to use different studies to demonstrate the genetic component of a phenotype. From the beginning of the century, many authors have studied the possible genetic transmission of longevity. The study of genealogies of ascendants first, and then of descendants of elderly individuals shows that the age at death incorrelated in people belonging to the same family. Finally, the studies carried out on monozygot and dizygot twins have made it possible to estimate that this genetic component accounts for approximately 10% of the individual's lifespan. Research on congenic mice which differ only by the chromosomic region of the Major Histocompatibility Complex (MHC) implies that this particular region might have an effect on longevity. However, the study of several alleles of the MHC indicates a complex sex-dependent influence. Several other chromosomic regions are also implied. As far as human beings are concerned, several research teams have worked on the HLA region. Once again, the situation is still far from clear.