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991.
Comparative study of meningitis dynamics across nine African countries: a global perspective 总被引:1,自引:0,他引:1
Hélène Broutin Solenne Philippon Guillaume Constantin de Magny Marie-Françoise Courel Benjamin Sultan Jean-François Guégan 《International journal of health geographics》2007,6(1):29
Background
Meningococcal meningitis (MM) represents an important public health problem especially in the "meningitis belt" in Africa. Although seasonality of epidemics is well known with outbreaks usually starting in the dry season, pluri-annual cycles are still less understood and even studied. In this context, we aimed at study MM cases time series across 9 sahelo-sudanian countries to detect pluri-annual periodicity and determine or not synchrony between dynamics. This global and comparative approach allows a better understanding of MM evolution in time and space in the long-term. 相似文献992.
Menvielle G Leclerc A Chastang JF Melchior M Luce D;Evolution Des Inégalités Sociales Par Causes Médicales de Décès 《American journal of public health》2007,97(11):2082-2087
Objectives. We investigated changes in socioeconomic inequalities in cancer mortality rates among men in France between 1968 and 1996.Methods. We used a representative sample of 1% of the French population and studied 4 periods (1968–1974, 1975–1981, 1982–1988, and 1990–1996). Causes of death were obtained by direct linkage with the French national death registry. The socioeconomic position of men aged 35 to 59 years was measured by using the occupational class reported at the time of the census at the beginning of each period. Analyses were conducted for all cancers and specifically for lung, upper aerodigestive tract, esophageal, colorectal, and other cancers.Results. In all analyses, we observed socioeconomic inequalities during the 4 periods considered; the inequalities increased between the first and the last period. Most of the total increase occurred between 1968 and 1981, and inequalities remained stable thereafter. Inequalities were larger when men out of the labor force were included in the analysis. The strongest increase in socioeconomic inequalities over time was observed for upper aerodigestive tract cancer.Conclusions. Although cancer mortality rates have decreased, substantial socioeconomic inequalities in cancer mortality among men remain.Changes over time in socioeconomic inequalities in mortality rates by cause of death among men have been examined principally in northern Europe, the United States, and the United Kingdom.1–7 In France, changes over time in socioeconomic inequalities in cause-specific mortality rates have not been examined extensively,8,9 and little is known regarding cancer mortality rates. The study of cancer mortality rates is of special interest in France because cancer rather than cardiovascular disease is the leading cause of premature mortality (before the age of 65 years). A comparative study found that cancer mortality contributed to approximately 40% of socioeconomic inequalities in total mortality in France, Italy, and Switzerland, compared with fewer than 20% in the United Kingdom and northern Europe.10 A comparative study including Italy, the United Kingdom, and northern European countries and focusing on time trends in socioeconomic inequalities in mortality rates found that trends in socioeconomic inequalities in cardiovascular mortality rates accounted for a large part of the change in the socioeconomic inequalities in all-cause mortality rates in all countries except Italy.11In addition, mortality rates by cancer site have been investigated in a few studies, but none of them have included data for France. Most of them have considered lung cancer2–4,6,7,12 and less often colorectal cancers separately.6,12 Few results are available on prostate6 and stomach cancer.4For lung cancer mortality rates, socioeconomic inequalities are observed in all countries; in France, large inequalities are also observed for non–lung cancer mortality rates.10 This is principally attributable to upper aerodigestive tract (UADT) cancers, which in France are both frequent and unequally distributed among social classes.13The situation in France is specific with regard to cancer mortality rates, with large socioeconomic inequalities in lung cancer and non–lung cancer mortality rates. Investigating changes in socioeconomic inequalities in cancer mortality rates by cancer site in this context may provide leads to identify factors associated with cancer incidence and survival, as well as to formulate prevention strategies.We describe changes in socioeconomic inequalities in cancer mortality among French men between 1968 and 1996. 相似文献
993.
Unprecedented heat-related deaths during the 2003 heat wave in Paris: consequences on emergency departments 下载免费PDF全文
Jean-Fran?ois Dhainaut Yann-Erick Claessens Christine Ginsburg Bruno Riou 《Critical care (London, England)》2003,8(1):1
In August 2003, France sustained an unprecedented heat wave that resulted in 14,800 excess deaths. The consequences were maximal
in the Paris area. The Assistance Publique–H?pitaux de Paris reported more than 2600 excess emergency department visits, 1900
excess hospital admissions, and 475 excess deaths despite a rapid organization. Indeed, simple preventice measures before
hospital admissions are only able to reduce mortality which mostly occurred at home and in nursing homes. 相似文献
994.
Prognostic value of the pulmonary dead-space fraction during the first 6 days of acute respiratory distress syndrome 总被引:4,自引:0,他引:4
BACKGROUND: The ratio of pulmonary dead space to tidal volume (VD/VT) in acute respiratory distress syndrome (ARDS) is reported to be between 0.35 and 0.55. However, VD/VT has seldom been measured with consideration to the evolving pathophysiology of ARDS. METHODS: We made serial VD/VT measurements with 59 patients who required mechanical ventilation for > or = 6 days. We measured VD/VT within 24 h of the point at which the patient met the American-European Consensus Conference criteria for ARDS, and we repeated the VD/VT measurement on ARDS days 2, 3, and 6 with a bedside metabolic monitor during volume-regulated ventilation. We analyzed the changes in VD/VT over the 6-day period to determine whether VD/VT has a significant association with mortality. RESULTS: VD/VT was significantly higher in nonsurvivors on day 1 (0.61 +/- 0.09 vs 0.54 +/- 0.08, p < 0.05), day 2 (0.63 +/- 0.09 vs 0.53 +/- 0.09, p < 0.001), day 3 (0.64 +/- 0.09 vs 0.53 +/- 0.09, p < 0.001), and day 6 (0.66 +/- 0.09 vs 0.51 +/- 0.08, p < 0.001). CONCLUSION: In ARDS a sustained VD/VT elevation is characteristic of nonsurvivors, so dead-space measurements made beyond the first 24 hours may have prognostic value. 相似文献
995.
DC-SIGN-mediated infectious synapse formation enhances X4 HIV-1 transmission from dendritic cells to T cells 总被引:16,自引:0,他引:16
Arrighi JF Pion M Garcia E Escola JM van Kooyk Y Geijtenbeek TB Piguet V 《The Journal of experimental medicine》2004,200(10):1279-1288
Dendritic cells (DCs) are essential for the early events of human immunodeficiency virus (HIV) infection. Model systems of HIV sexual transmission have shown that DCs expressing the DC-specific C-type lectin DC-SIGN capture and internalize HIV at mucosal surfaces and efficiently transfer HIV to CD4+ T cells in lymph nodes, where viral replication occurs. Upon DC-T cell clustering, internalized HIV accumulates on the DC side at the contact zone (infectious synapse), between DCs and T cells, whereas HIV receptors and coreceptors are enriched on the T cell side. Viral concentration at the infectious synapse may explain, at least in part, why DC transmission of HIV to T cells is so efficient.Here, we have investigated the role of DC-SIGN on primary DCs in X4 HIV-1 capture and transmission using small interfering RNA-expressing lentiviral vectors to specifically knockdown DC-SIGN. We demonstrate that DC-SIGN- DCs internalize X4 HIV-1 as well as DC-SIGN+ DCs, although binding of virions is reduced. Strikingly, DC-SIGN knockdown in DCs selectively impairs infectious synapse formation between DCs and resting CD4+ T cells, but does not prevent the formation of DC-T cells conjugates.Our results demonstrate that DC-SIGN is required downstream from viral capture for the formation of the infectious synapse between DCs and T cells. These findings provide a novel explanation for the role of DC-SIGN in the transfer and enhancement of HIV infection from DCs to T cells, a crucial step for HIV transmission and pathogenesis. 相似文献
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Jean-Fran?ois Dorval Pascale Geoffroy Martin G Sirois Jean-Fran?ois Tanguay 《Journal of endovascular therapy》2006,13(1):104-110
PURPOSE: To investigate the effect of endovascular cryotherapy (Cryo) on the density of collagen types I (CI) and III (CIII), which are involved in the dynamic modulation of extracellular matrix (ECM) after percutaneous transluminal angioplasty (PTA). METHODS: Twenty-one juvenile farm swine and 10 miniswine underwent PTA of the femoral arteries with and without Cryo (-50 degrees C for 2 minutes). Quantitative angiography, histomorphometry, and quantification of CI and CIII were performed at 1 week (n=7), 1 month (n=7), 3 months (n=7), and 6 months (n=10). RESULTS: PTA decreased the minimal luminal diameter (MLD) (range 3.48+/-0.18 to 4.2+/-0.39 mm) compared to baseline values (range 3.67+/-0.15 to 4.59+/-0.23 mm), but the application of Cryo maintained the MLDs at preprocedural levels (range 3.88+/-0.31 to 4.58+/-0.21 mm). At the time of sacrifice, the MLDs were similar in PTA and Cryo-treated arteries, but the external elastic lamina was significantly greater after Cryo application (range 10.17+/-0.54 to 14.34+/-0.76 mm2) than after PTA (range 8.69+/-0.70 to 11.77+/-0.73 mm2, p<0.05). Cryo did not alter the luminal area or prevent neointimal growth. A time-dependent increase of both CI and CIII was observed as early as 1 week after PTA, peaking at 3 months, and declining thereafter. Cryo accentuated this increase at all time points. CONCLUSION: The application of Cryo accentuates the accumulation of CI and CIII in PTA-treated femoral arteries. This effect may be of clinical relevance in the stabilization of peripheral atherosclerotic plaque. 相似文献