BackgroundEpidemiological data on the prevalence of headache in nursing staff in Mainland China are lacking. We therefore performed a study to assess the prevalence of headache, and factors associated with headaches, in nursing staff in three hospitals in North China.MethodsStratified random cluster sampling was used to select 1102 nurses from various departments in three hospitals. A structured questionnaire was used to collect epidemiological data, headache characteristics and associated factors.ResultsThe response rate was 93.0%. Among nursing staff, the 1-year prevalence of primary headache disorders was 45.3%, of migraine 14.8% (migraine with aura 3.4%, migraine without aura 11.4%), of tension-type headache (TTH) 26.2%, of chronic daily headache (CDH) 2.7%. Multivariate analysis showed that seniority (≥5 years) was a risk factor for migraine (OR 2.280), obesity (BMI ≥ 25) was a risk factor for TTH and CDH (OR 1.684 and 3.184), and age (≥40 years) was a risk factor for CDH (OR 8.455). Nurses working in internal medicine were more likely to suffer CDH than those in other departments. Working a greater number of night shifts was also associated with increased prevalence of headache.ConclusionThe prevalence of primary headache disorders in nurses is higher than that in the general population in China, and occupational factors may play an important role. Therefore, the prevalence of headache in nurses should be a focus of attention, and coping strategies should be provided. Such measures could contribute to improving patient care.
In parallel imaging, the signal-to-noise ratio (SNR) of sensitivity encoding (SENSE) reconstruction is usually degraded by the ill-conditioning problem, which becomes especially serious at large acceleration factors. Existing regularization methods have been shown to alleviate the problem. However, they usually suffer from image artifacts at high acceleration factors due to the large data inconsistency resulting from heavy regularization. In this paper, we propose Bregman iteration for SENSE regularization. Unlike the existing regularization methods where the regularization function is fixed, the method adaptively updates the regularization function using the Bregman distance at different iterations, such that the iteration gradually removes the aliasing artifacts and recovers fine structures before the noise finally comes back. With a discrepancy principle as the stopping criterion, our results demonstrate that the reconstructed image using Bregman iteration preserves both sharp edges lost in Tikhonov regularization and fines structures missed in total variation (TV) regularization, while reducing more noise and aliasing artifacts. Magn Reson Med 61: 145-152, 2009.
The role of neutrophils in bone regeneration remains elusive. In this study, it is shown that intramuscular implantation of interleukin-8 (IL-8) (commonly recognized as a chemotactic cytokine for neutrophils) at different levels lead to outcomes resembling those of fracture hematoma at various stages. Ectopic endochondral ossification is induced by certain levels of IL-8, during which neutrophils are recruited to the implanted site and are N2-polarized, which then secrete stromal cell-derived factor-1 (SDF-1 ) for bone mesenchymal stem cell (BMSC) chemotaxis via the SDF-1/CXCR4 (C-X-C motif chemokine receptor 4) axis and its downstream phosphatidylinositol 3'-kinase (PI3K)/Akt pathway and -catenin-mediated migration. Neutrophils are pivotal for recruiting and orchestrating innate and adaptive immunocytes, as well as BMSCs at the initial stage of bone healing and regeneration. The results in this study delineate the mechanism of neutrophil-initiated bone regeneration and interaction between neutrophils and BMSCs, and innate and adaptive immunities. This work lays the foundation for research in the fields of bone regenerative therapy and biomaterial development, and might inspire further research into novel therapeutic options.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.