Archaeological excavations carried out in two ancient cemeteries (1657-1844) of Notre-Dame-de-Québec Basilica in old Québec City allowed us to analyze the skeletal remains of more than 175 children who died before they were 10 years old. The proportion of infants is higher than expected according to the parish registers presumably because archaeologists recovered the remains of infants whose death had not been recorded in the registers. Two peaks of mortality have been noted: among the newborns and between one and two years old. The observed bone lesions lead us to believe that prenatal stress and rickets might be responsible for these high mortality rates. Although the samples from the two cemeteries were contemporaneous and drawn from the same community, there are some significant differences from the morbidity and mortality standpoint, tentatively attributed to the fact that most of the children recovered from one of the cemeteries were the victims of an epidemic while those from the other cemetery died in normal circumstances. This study shows how the analysis of skeletal remains can shed light on pathological conditions which otherwise would remain undocumented and how paleoanthropology opens new perspectives of research on diseases and death in the past.
BACKGROUND: After a large increase during the 19th and the 20th century, for two decades the gap in life expectancy between sexes has been reducing in most industrialised countries. In France, where it was specially large, it stopped increasing in the early 1980s and decreased in the most recent years. The paper investigates reasons for these recent trends in France and in the industrialised countries. METHODS: Two types of data are used for analysis. Death probabilities from life tables are used for calculating male excess mortality by age and estimating the role of various age groups in life expectancy differences by sex. Sex- and cause-specific mortality rates from INED database for France and from WHO database for other countries are used to assess the part played by various causes of death in the gender gap and its evolution. RESULTS: In France, the stabilisation of the gap is mainly related to the decrease in cardiovascular mortality for men who benefit from the same progress but later than women. In the most recent years, the reduction of the gap is due to the trend reversal of male cancer mortality which is now decreasing, specially because of the reduction of lung cancer mortality. In European countries, taken as examples (England & Wales, Sweden, Switzerland, Italy) cardiovascular mortality is also the main responsible for the decreasing differences. Conversely, in Japan, the gap is still increasing specially for mortality from cancer and respiratory diseases. CONCLUSIONS: The recent gap narrowing between male and female life expectancy in France is not a specific case. It does not mean that female health situation is worsening but it is related to an acceleration of progress for males. This reduction will most probably go on in the next years, except if females would enjoy dramatic progression in old age mortality.
INTRODUCTION: The global warming of the planet and its anthropogenic origin are no longer debatable. Nevertheless, from a medical point of view, while the epidemiological consequences of the warming are rather well-known, the biological consequences are still poorly documented. This is a good example of evolutionary (or darwinian) medicine. METHODS: The research strategy of this systematic review is based on both PubMed during the period of 2000-2007 and several reviews articles for the period >2000. RESULTS: From a medical point of view, there are four types of consequences. 1-The simple elevation of the average external temperature is accompanied by an increased global mortality and morbidity, the mortality/external temperature is a J curve, with the warm branch more pronounced than the cold one. A recent study on 50 different cities had confirmed that global, and more specifically cardiovascular mortalities were enhanced at the two extreme of the temperatures. 2-The acute heatwaves, such as that which happened in France in August 2003, have been studied in detail by several groups. The mortality which was observed during the recent heatwaves was not compensated by harvesting, strongly suggesting that we were dealing with heat stroke, and that such an increased mortality was more reflecting the limits of our adaptational capacities than aggravation of a previously altered health status. 3-Climate changes have modified the repartition and virulence of pathogenic agents (dengue, malaria...) and above all their vectors. Such modifications were exponential and are likely to reflect the biological properties of parasites. 4-Indirect consequences of global warming include variations in the hydraulic cycle, the new form of tropical hurricanes and many different changes affecting both biodiversity and ecosystems. They will likely result in an increased level of poverty. DISCUSSION: These finding gave rise to several basic biological questions, rarely evoked, and that concern the limits of the adaptational capacities of human genome. Our genome has indeed been shaped in the past by a rather cold environment which has acutely been modified. The immediate physiological regulation includes sweating and skin vasodilatation. The latter may strongly enhance the cardiac output which explains the heat-induced cardiac decompensation. Long term regulation depends upon the numerous mechanisms of uncoupling of the mitochondrial respiration. For the moment, the thermolytic mechanisms and their regulation were rather poorly documented.