Histone H4K20 methylation mediated chromatin compaction threshold ensures genome integrity by limiting DNA replication licensing

Cell cycle and replication need to be tightly regulated to ensure genome stability in mammalian cells. Here the authors provide a link between chromatin structure and DNA replication regulation by showing that chromatin compaction limits replication licensing thereby promoting genome integrity

DNA Replication Fading As Proliferating Cells Advance in Their Commitment to Terminal Differentiation

Terminal differentiation is the process by which cycling cells stop proliferating to start new specific functions. It involves dramatic changes in chromatin organization as well as gene expression. In the present report we used cell flow cytometry and genome wide DNA combing to investigate DNA replication during murine erythroleukemia-induced terminal cell differentiation. The results obtained indicated that the rate of replication fork movement slows down and the inter-origin distance becomes shorter during the precommitment and commitment periods before cells stop proliferating and accumulate in G1. We propose this is a general feature caused by the progressive heterochromatinization that characterizes terminal cell differentiation

Longitudinal study assessing the return of chloroquine susceptibility of Plasmodium falciparum in isolates from travellers returning from West and Central Africa, 2000-2011.

BACKGROUND: Chloroquine (CQ) was the main malaria therapy worldwide from the 1940s until the 1990s. Following the emergence of CQ-resistant Plasmodium falciparum, most African countries discontinued the use of CQ, and now promote artemisinin-based combination therapy as the first-line treatment. This change was generally initiated during the last decade in West and Central Africa. The aim of this study is to describe the changes in CQ susceptibility in this African region, using travellers returning from this region as a sentinel system. METHODS: The study was conducted by the Malaria National Reference Centre, France. The database collated the pfcrtK76T molecular marker for CQ susceptibility and the in vitro response to CQ of parasites from travellers' isolates returning from Senegal, Mali, Ivory Coast or Cameroon. As a proxy of drug pressure, data regarding CQ intake in febrile children were collated for the study period. Logistic regression models were used to detect trends in the proportions of CQ resistant isolates. RESULTS: A total of 2874 parasite isolates were genotyped between 2000-2011. The prevalence of the pfcrt76T mutant genotype significantly decreased for Senegal (from 78% to 47%), Ivory Coast (from 63% to 37%), Cameroon (from 90% to 59%) and remained stable for Mali. The geometric mean of the 50% inhibitory concentration (IC50) of CQ in vitro susceptibility and the proportion of resistant isolates (defining resistance as an IC50 value > 100 nM) significantly decreased for Senegal (from 86 nM (59%) to 39 nM (25%)), Mali (from 84 nM (50%) to 51 nM (31%)), Ivory Coast (from 75 nM (59%) to 29 nM (16%)) and Cameroon (from 181 nM (75%) to 51 nM (37%)). Both analyses (molecular and in vitro susceptibility) were performed for the 2004-2011 period, after the four countries had officially discontinued CQ and showed an accelerated decline of the resistant isolates for the four countries. Meanwhile, CQ use among children significantly deceased in this region (fixed effects slope = -0.3, p < 10-3). CONCLUSIONS: An increase in CQ susceptibility following official withdrawal of the drug was observed in travellers returning from West and Central African countries. The same trends were observed for molecular and in vitro analysis between 2004-2011 and they correlated to the decrease of the drug pressure

Pathologie des étrangers ou des migrants. Problèmes cliniques et thérapeutiques, enjeux de santé publique

Pathology of the strangers or the migrants. Clinical and therapeutical problems, stakes of public health. Denis MECHALI Numerous health problems are noticed in immigrant people or foreigners. Many are similar of those of natives but some are specific to this population. Specific and technical knowledge is essential, especially for diseases unknown in natives. But, even in these cases, physician has to know other aspects, particularly epidemiologic and social aspects. Severity and duration of the pathology must be evaluated for the patient and the circle (especially for transmissible disease). In the same manner, feasibility and cost of diagnosis and therapy must be known and assessed. An accurate thinking must permit to be in harmony with the three matters: technical relevance, satisfactory answer for patients and acceptable value in term of public health.Pathologie des étrangers ou des migrants. Problèmes cliniques et thérapeutiques, enjeux de santé publique. Denis MECHALI Les problèmes de santé posés par les sujets migrants ou étrangers sont multiples. Ils ne sont pas toujours spécifiques. Beaucoup sont semblables à ceux de l'ensemble de la collectivité. Une connaissance technique spécifique est indispensable pour certaines affections absentes chez les autochtones. Mais, même dans ces cas, le médecin doit faire appel à d'autres éléments, épidémiologiques et sociaux notamment, pour avoir une vision exacte. Il faut en effet évaluer la probabilité d'une pathologie donnée, sa gravité à court moyen ou long terme pour l'individu et son entourage, en particulier s'il s'agit d'une pathologie transmissible. Cela aboutit à évaluer les possibilités et les coûts diagnostiques et thérapeutiques. Une réflexion précise doit permettre d'harmoniser les trois registres d'une pertinence technique, d'une réponse satisfaisante pour les intéressés et d'une valeur acceptable en terme de Santé publique.Patología de los extranjeros o de los migrantes. Problemas clínicos y terapeúticos, puesta de salud pública. Denis MECHALI Los problemas de salud planteados por los individuos migrantes o extranjeros son multiples. No son siempre específicos. Muchos se parecen a los del conjunto de la colectividad. Cierto conocimiento técnico específico es imprecindible para cíertas afeccíones ausentes para los autóctonos. Pero incluso en esos casos el médico debe interesarse en otros elementos, epidemiólogicos y sociales particulamente, para tener una visión exacta. Hay que evaluar efectivamente la probabilidad de una patología dada, su gravedad a corto, medio o largo plazo para el individuo y su entorno, en particular si se trata de una patología transmisible. Esto tiene como consecuencia la evaluación de las posibilidades y los costos diagnósticos y terapeúticos. Una reflexión precisa debe permitir la amortiguación de los tres registros de una pertinencia técnica, una respuesta satisfactoria para los interesados y un valor aceptable en término de Salud pública.Mechali Denis. Pathologie des étrangers ou des migrants. Problèmes cliniques et thérapeutiques, enjeux de santé publique. In: Revue européenne des migrations internationales, vol. 6, n°3,1990. pp. 99-127

Les groupes sanguins ABO et Rh des Juifs du Maroc.

Mechali D., Leveque J., Faure P. Les groupes sanguins ABO et Rh des Juifs du Maroc.. In: Bulletins et Mémoires de la Société d'anthropologie de Paris, X° Série. Tome 8 fascicule 5-6, 1957. pp. 354-370

Geminin is cleaved by caspase-3 during apoptosis in Xenopus egg extracts

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