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961.
Despite a late start within the realm of arthroscopy, foot and ankle arthroscopy proves to be an important diagnostic and treatment tool for the foot and ankle specialist. As indication for arthroscopy increases, complications associated with foot and ankle arthroscopy must be revisited. We reviewed 405 foot and ankle arthroscopic procedures performed on 390 patients in 4 different facilities over a 3-year period extending from January 2005 to August 2008. Two-hundred-sixty foot and ankle arthroscopic procedures on 251 patients met our inclusion criteria. A total of 246 ankle and 14 posterior subtalar arthroscopic procedures were performed with a mean follow-up of 10.7 ± 3.5 months. Patient demographics, preoperative findings, intraoperative technique, and postoperative course were reviewed. We failed to identify statistically significant predictive factors for complications. Arthroscopy performed in combination with adjunctive procedures showed a trend toward higher complication rate, although statistical significance was not noted. Overall, 20 cases (7.69%) experienced arthroscopy-related complications, and this finding was comparable with previously published results. The most common complication was cutaneous nerve injury, which involved 9 cases (3.46%), and localized superficial infection, which involved 8 cases (3.08%). Injury to the superficial peroneal nerve accounted for 5 of the cutaneous nerve injuries. There were no cases of arthroscopy-related vascular injury. All cases of superficial postoperative infection resolved with antibiotic therapy, and none of the cases required return to the operating room. These results were also similar to published data.  相似文献   
962.
The natural history for patients with de novo donor‐specific antibodies (dnDSA) and the risk factors for its development have not been well defined. Furthermore, clinical and histologic correlation with serologic data is limited. We studied 315 consecutive renal transplants without pretransplant DSA, with a mean follow‐up of 6.2 ± 2.9 years. Protocol (n = 215) and for cause (n = 163) biopsies were analyzed. Solid phase assays were used to screen for dnDSA posttransplant. A total of 47 out of 315 (15%) patients developed dnDSA at a mean of 4.6 ± 3.0 years posttransplant. Independent predictors of dnDSA were HLA‐DRβ1 MM > 0 (OR 5.66, p < 0.006); and nonadherence (OR 8.75, p < 0.001); with a strong trend toward clinical rejection episodes preceding dnDSA (OR 1.57 per rejection episode, p = 0.061). The median 10‐year graft survival for those with dnDSA was lower than the No dnDSA group (57% vs. 96%, p < 0.0001). Pathology consistent with antibody‐mediated injury can occur and progress in patients with dnDSA in the absence of graft dysfunction and furthermore, nonadherence and cellular rejection contribute to dnDSA development and progression to graft loss.  相似文献   
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Gomez–Lopez‐Hernandez syndrome (GLHS) is a rare neurocutaneous disorder. We are aware of thirty previously reported cases. We present four additional patients with this condition. Previously reported patients have shown the hallmark triad of rhombocephalosynapsis, trigeminal anesthesia, and bilateral parietal or parieto‐occipital alopecia. Rhombencephalosynapsis consists of agenesis of the cerebellar vermis, fusion of the cerebellar hemispheres, and the dentate nuclei. The gene or genes responsible for GLHS remain unknown. Alopecia is seen in all previously reported cases of GLHS. Additional craniofacial findings such as low‐set and posteriorly rotated ears, midface retrusion, craniosynostosis, and brachyturricephaly are also very common in this syndrome. Trigeminal anesthesia, reported in the original three patients, is seen in just over half of reported patients. Most patients with GLHS have motor delays, intellectual disability, and hypotonia. Unusual stereotypic movements of the head are seen in many patients with GLHS. Neuroimaging of patients with GLHS shows rhombencephalosynapsis is universally present, with ventriculomegaly/hydrocephalus and cerebellar hypoplasia being common. We propose that rhombencephalosynapsis and scalp alopecia are necessary, but by themselves not sufficient, for a diagnosis of GLHS. Additional findings of trigeminal anesthesia or one of two major craniofacial findings (brachycephaly and/or turricephaly or midface retrusion) are sufficient to make a diagnosis of GLHS. Additional categories of probable and possible GLHS are proposed for patients whose examination may be compatible with a diagnosis of GLHS, but CNS imaging has not yet been obtained. © 2013 Wiley Periodicals, Inc.  相似文献   
965.
Iron dyshomeostasis is proving increasingly likely to be involved in the pathology of Alzheimer's disease (AD); yet, its mechanism is not well understood. Here, we investigated the AD-related mechanism(s) of iron-sulfate exposure in vitro and in vivo, using cultured primary cortical neurons and APP/PS1 AD-model mice, respectively. In both systems, we observed iron-induced disruptions of amyloid precursor protein (APP) processing, neuronal signaling, and cognitive behavior. Iron overload increased production of amyloidogenic KPI-APP and amyloid beta. Further, this APP misprocessing was blocked by MK-801 in vitro, suggesting the effect was N-methyl-d-aspartate receptor (NMDAR) dependent. Calcium imaging confirmed that 24 hours iron exposure led to disrupted synaptic signaling by augmenting GluN2B-containing NMDAR expression–GluN2B messenger RNA and protein levels were increased and promoting excessing extrasynaptic NMDAR signaling. The disrupted GluN2B expression was concurrent with diminished expression of the splicing factors, sc35 and hnRNPA1. In APP/PS1 mice, chronic iron treatment led to hastened progression of cognitive impairment with the novel object recognition discrimination index, revealing a deficit at the age of 4 months, concomitant with augmented GluN2B expression. Together, these data suggest iron-induced APP misprocessing and hastened cognitive decline occur through inordinate extrasynaptic NMDAR activation.  相似文献   
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967.
Objectives: To compare the outcomes of restorations placed by restorative function auxiliaries (RFAs) with those placed by dentists. Methods: Between July 1, 2007, and June 30, 2008, we matched 455 restorations placed by RFAs working at HealthPartners Dental Group with the same number placed by dentists. Restorations were matched by tooth number, American Dental Association procedure code, and patient age‐group. Results: Of 910 restorations, 17 (1.9 percent) had problems potentially related to the filling or crown placement during the first year. Problem rates were not significantly different (p = 0.33) for restorations placed by RFAs (1.3 percent, 6 of 455) and those placed by dentists (2.4 percent, 11 of 455). Conclusions: There was no significant difference in problem rates for restorations placed by RFAs versus those placed by dentists. This finding may free dentists to handle more difficult cases, alleviating some of the pressures of daily practice and meeting the need for improved access.  相似文献   
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