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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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ApoB-100 and Phosphatidylcholine-specific phospholipase C (PC-PLC) are important contributors to atherosclerosis development. ApoB-100 is the main structural protein of LDL, being directly associated with atherosclerosis plaque generation. PC-PLC is highly expressed in atherosclerosis lesions and contributes to their progression. We show how phosphatidylcholine-coated nanomicelles can be used for specific characterisation of atherosclerosis plaque. Results show that ApoB-100 in the protein corona of the nanomicelle targets the particles to atherosclerotic areas in apolipoprotein E?/? mice. Furthermore, PC-PLC selectively removes the polar heads from the phospholipid coating of the nanomicelles leading to their accumulation. To fully characterise the behaviour of the nanomicelles, we developed multimodal probes using a nanoemulsion step. Hybrid imaging revealed plaque accumulation of the nanomicelles and colocalisation with PC-PLC expression and ApoB-100 in the plaque. This study shows how protein corona composition and enzyme-driven nanomaterial accumulation can be used for detection of atherosclerosis.  相似文献   
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