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Objective

To assess the incidence of pertussis (whooping cough) in subjects aged 50 years and older in France.

Methods

Participating family physicians (FPs) using the patient record management software AxiSanté® included patients aged 50 years and older, who had signed an informed consent form, presenting with persistent cough for 7 to 21 days. Bordetella genetic material was detected by polymerase chain reaction (PCR) on nasopharyngeal samples collected at the FP's discretion.

Results

A total of 42 FPs included 129 patients from June 2013 to August 2014 (large cities: 38; medium-sized cities: 57; rural areas: 34); 106 samples were analyzed. Overall, 30 pertussis cases were diagnosed: 10 cases confirmed by PCR, 18 purely clinical cases, and two direct epidemiological cases. The crude incidence rate per 100,000 patients aged  50 years was 103.6 (95% CI: 69.9–47.9): 77.1 in large cities, 103.1 in medium-sized cities, and 143.9 in rural areas. The extrapolated incidence rate per 100,000 persons aged  50 years was 187.1 (95% CI: 126.2–67.1): 131.1 in large cities, 256.1 in medium-sized cities, and 242.2 in rural areas.

Conclusion

The population aged 50 years and older can serve as a reservoir. Its role in Bordetella pertussis circulation should be taken into account for pertussis booster vaccination programs.  相似文献   
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Iron-oxide nanoparticles (NPs) generated by environmental events are likely to represent health problems. α-Fe2O3 NPs were synthesized, characterized and tested in a model for toxicity utilizing human whole blood without added anticoagulant. MALDI-TOF of the corona was performed and activation markers for plasma cascade systems (complement, contact and coagulation systems), platelet consumption and release of growth factors, MPO, and chemokine/cytokines from blood cells were analyzed. The coronas formed on the pristine α-Fe2O3 NPs contained contact system proteins and they induced massive activation of the contact (kinin/kallikrein) system, as well as thrombin generation, platelet activation, and release of two pro-angiogeneic growth factors: platelet-derived growth factor and vascular endothelial growth factor, whereas complement activation was unaffected. The α-Fe2O3 NPs exhibited a noticeable toxicity, with kinin/kallikrein activation, which may be associated with hypotension and long-term angiogenesis in vivo, with implications for cancer, arteriosclerosis and pulmonary disease.  相似文献   
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Proximal tubules in the kidney play a crucial role in reabsorbing and eliminating substrates from the body into the urine, leading to high local concentrations of xenobiotics. This makes the proximal tubule a major target for drug toxicity that needs to be evaluated during the drug development process. Here, we describe an advanced in vitro model consisting of fully polarized renal proximal tubular epithelial cells cultured in a microfluidic system. Up to 40 leak-tight tubules were cultured on this platform that provides access to the basolateral as well as the apical side of the epithelial cells. Exposure to the nephrotoxicant cisplatin caused a dose-dependent disruption of the epithelial barrier, a decrease in viability, an increase in effluent LDH activity, and changes in expression of tight-junction marker zona-occludence 1, actin, and DNA-damage marker H2A.X, as detected by immunostaining. Activity and inhibition of the efflux pumps P-glycoprotein (P-gp) and multidrug resistance protein (MRP) were demonstrated using fluorescence-based transporter assays. In addition, the transepithelial transport function from the basolateral to the apical side of the proximal tubule was studied. The apparent permeability of the fluorescent P-gp substrate rhodamine 123 was decreased by 35% by co-incubation with cyclosporin A. Furthermore, the activity of the glucose transporter SGLT2 was demonstrated using the fluorescent glucose analog 6-NBDG which was sensitive to inhibition by phlorizin. Our results demonstrate that we developed a functional 3D perfused proximal tubule model with advanced renal epithelial characteristics that can be used for drug screening studies.  相似文献   
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