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41.
The role of retinal microglial cells (MCs) in age-related macular degeneration (AMD) is unclear. Here we demonstrated that all retinal MCs express CX3C chemokine receptor 1 (CX3CR1) and that homozygosity for the CX3CR1 M280 allele, which is associated with impaired cell migration, increases the risk of AMD. In humans with AMD, MCs accumulated in the subretinal space at sites of retinal degeneration and choroidal neovascularization (CNV). In CX3CR1-deficient mice, MCs accumulated subretinally with age and albino background and after laser impact preceding retinal degeneration. Raising the albino mice in the dark prevented both events. The appearance of lipid-bloated subretinal MCs was drusen-like on funduscopy of senescent mice, and CX3CR1-dependent MC accumulation was associated with an exacerbation of experimental CNV. These results show that CX3CR1-dependent accumulation of subretinal MCs evokes cardinal features of AMD. These findings reveal what we believe to be a novel pathogenic process with important implications for the development of new therapies for AMD.  相似文献   
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Little is known of the natural history of thymic carcinoids in multiple endocrine neoplasia type 1 (MEN1). This is important because in 1993 they were identified as a frequent cause of death, yet only small retrospective studies and case reports exist. We report results of a prospective study of 85 patients with MEN1 evaluated for pancreatic endocrine tumors and followed over a mean of 8 yr with serial chest computed tomography, magnetic resonance imaging (MRI), chest x-ray, and, since 1994, octreoscans [somatostatin receptor scintigraphy (SRS)]. Seven patients (8%) developed thymic carcinoids. Patients with and without carcinoids did not differ in clinical, laboratory, or MEN1 tumor features, except for male gender and the presence of a gastric carcinoid. All thymic tumors were hormonally inactive. Four thymic carcinoids lacked 11q loss of heterozygosity, although it was found in three pancreatic endocrine tumors. Computed tomography and/or MRI were more sensitive than SRS or chest x-ray in detecting tumors initially or with recurrence. All patients underwent resection of the thymic carcinoid, and in all patients followed more than 1 yr, the tumor recurred. Bone metastases developed in two patients and were detected early only on MRI, not SRS. This study provides information on early thymic carcinoids and allows modifications of existing guidelines to be recommended for their diagnosis, surveillance, and treatment.  相似文献   
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Homeless urbanites are a heterogeneous population with unique health and social service needs. The study examined situational, behavioral, health-related and resource indicators in terms of their direct impact on frailty, hypothesized as a latent variable. Using structural equation modeling (SEM), a model was tested with 150 homeless men and women, ages 40–73, from three homeless day center drop-in sites on Skid Row and one residential drug treatment (RDT) facility that works with homeless parolees and probationers. In bivariate analyses with the latent construct frailty, months homeless (p < 0.01), female gender (p < 0.05), education (p < 0.05), comorbid conditions (p < 0.001), nutrition (p < 0.001), resilience (p < 0.001), health care utilization (p < 0.01), and falls (p < 0.001) were significantly associated with frailty. In the final path model, significant predictors of frailty included educational attainment (p < 0.01), comorbid conditions (p < 0.001), nutrition (p < 0.001), resilience (p < 0.001), and falls (p < 0.01). These findings will serve as a foundation for future nurse-led, community-based initiatives that focus on key predictors of frailty among the homeless and the development of interventions.  相似文献   
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Robotic surgery offers potential technical advantages that may facilitate pancreatic resection. The aim of this study was to evaluate the learning curve and short-term perioperative outcomes in patients who underwent laparoscopic and robot-assisted distal pancreatectomy. All perioperative variables were evaluated and compared retrospectively between laparoscopic (LDP) (n = 23) and robot-assisted (RDP) (n = 11) distal pancreatectomy. The mean total operative time was shorter in LDP (194 vs. 225 min; p = 0.017). All other perioperative criteria were similar between LDP and RDP patients (blood loss, transfusion rate, conversion, pancreatic fistula, postoperative morbidity, and duration of hospitalization). Non-adjusted CUSUM curve for composite events including operative time, conversion, postoperative morbidity and reoperation rates showed that the RDP learning curve corresponded to the first seven consecutive patients. During early experience, RDP was associated with longer operative time but similar short-term perioperative outcomes compared to conventional distal pancreatectomy.  相似文献   
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Pediatric diffuse midline gliomas are devastating diseases. Among them, diffuse midline gliomas H3K27M‐mutant are associated with worse prognosis. However, recent studies have highlighted significant differences in clinical behavior and biological alterations within this specific subgroup. In this context, simple markers are needed to refine the prognosis of diffuse midline gliomas H3K27M‐mutant and guide the clinical management of patients. The aims of this study were (i) to describe the molecular, immunohistochemical and, especially, chromosomal features of a cohort of diffuse midline gliomas and (ii) to focus on H3K27M‐mutant tumors to identify new prognostic markers. Patients were retrospectively selected from 2001 to 2017. Tumor samples were analyzed by immunohistochemistry (including H3K27me3, EGFR, c‐MET and p53), next‐generation sequencing and comparative genomic hybridization array. Forty‐nine patients were included in the study. The median age at diagnosis was 9 years, and the median overall survival (OS) was 9.4 months. H3F3A or HIST1H3B mutations were identified in 80% of the samples. Within the H3K27M‐mutant tumors, PDGFRA amplification, loss of 17p and a complex chromosomal profile were significantly associated with worse survival. Three prognostic markers were identified in diffuse midline gliomas H3K27M‐mutant: PDGFRA amplification, loss of 17p and a complex chromosomal profile. These markers are easy to detect in daily practice and should be considered to refine the prognosis of this entity.  相似文献   
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