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31.
Abstract

Objective: The Unified Classification System (UCS) presents itself as an evolution of the Vancouver Classification (VCS) for the evaluation of periprosthetic fractures of the proximal femur (PPF). The aim of our study was to highlight any loss of reproducibility or validity of the new classification system, compared to the previous one.

Material and methods: We tested the interobserver and intraobserver agreement using 40 PPF clinical cases. Each classifying subtype of the UCS and VCS was present in at least two cases. Six experienced hip surgeons (Senior Surgeon, SS) and 5 surgeons in training (Junior Surgeon, JS) classified the clinical cases, using VCS and UCS. The validity of both classifications was then tested with intraoperative surveys.

Results: The mean κ value for interobserver agreement for the VCS in the JS group was 0.65 and 0.81 for the SS group. The mean κ value for interobserver agreement for the UCS in the JS group was 0.63 and 0.65 for the SS group. The mean κ value for intraobserver agreement for the VCS in the JS group was 0.71 and 0.73 for the SS group. The mean κ value for intraobserver agreement for the UCS in the JS group was 0.72 and 0.7 for the SS group. Validity analysis showed a moderate agreement for the VCS and a good agreement for the UCS.

Conclusion: The UCS completes the Vancouver classification, expanding it. It is reliable, despite the increase in classification categories and number of parameters to evaluate, with a slightly higher validity.  相似文献   
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A 4‐year‐old girl with clinical and laboratory signs of Kawasaki disease (KD) was hospitalized and given intravenous immunoglobulin plus aspirin therapy, with rapid defervescence and clinical improvement, and was discharged 48 hours after admission. At the time of her follow‐up echocardiography on day 14, orange‐brown pigmentation of the nail beds was noticed and confirmed with dermoscopy. No clear association between KD and orange‐brown chromonychia has been demonstrated, although reports and case series suggest a possible link between these two entities. We suggest that this particular finding might be encompassed in late (subacute) changes of extremities as part of KD diagnostic criteria.  相似文献   
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ABSTRACT: BACKGROUND: Familial partial lipodystrophies (FPLD) are clinically heterogeneous disorders characterized by selective loss of adipose tissue, insulin resistance and metabolic complications. Until genetic studies become available for clinical practice, clinical suspicion and pattern of fat loss are the only parameters leading clinicians to consider the diagnosis. The objective of this study was to compare body composition by dual energy X-ray absorptiometry (DXA) in patients with FPLD and control subjects, aiming to find objective variables for evaluation of FPLD. METHODS: Eighteen female patients with partial lipodystrophy phenotype and 16 healthy controls, matched for body mass index, sex and age were studied. All participants had body fat distribution evaluated by DXA measures. Fasting blood samples were obtained for evaluation of plasma leptin, lipid profile and inflammatory markers. Genetic studies were carried out on the 18 patients selected that were included for statistical analysis. Thirteen women confirmed diagnosis of Dunnigan-type FPLD (FPLD2). RESULTS: DXA revealed a marked decrease in truncal fat and 3 folds decrease in limbs fat percentage in FPLD2 patients (p <0.001). Comparative analysis showed that ratio between trunk and lower limbs fat mass, characterized as Fat Mass Ratio (FMR), had a greater value in FLPD2 group (1.86 +/- 0.43 vs controls 0.93 +/- 0.10; p <0.001) and a improved accuracy for evaluating FPLD2 with a cut-off point of 1.2. Furthermore, affected women showed hypoleptinemia (FLPD2 4.9 +/- 2.0 vs controls 18.2 +/- 6.8; p <0.001), insulin resistance and a more aggressive lipid profile. CONCLUSION: In this study, assessment of body fat distribution by DXA permitted an objective characterization of FLPD2. A consistent pattern with marked fat reduction of lower body was observed in affected patients. To our knowledge this is the first time that cut-off values of objective variables were proposed for evaluation of FPLD2.  相似文献   
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Vascular disorders can either be cause or consequence in the pathophysiology of Alzheimer’s disease (AD). To comprehensively characterize the occurrence of vascular impairment in a double transgenic mouse model for AD (APPswe/PS1dE9) during aging, we developed a new method to obtain microvascular relative cerebral blood volume (rCBVmicro) maps from gradient echo MR imaging by histogram evaluation and we applied a voxel-wise approach to detect rCBVmicro changes. With this methodology the development of cerebral microvascular impairments can be described in vivo with 0.16 mm isotropic resolution for the whole mouse brain. At 8 months, impaired rCBVmicro appeared in some cortical regions and in the thalamus, which spreads over several sub-cortical areas and the hippocampus at 13 months. With a ROI-based approach, we further showed that hippocampal rCBVmicro in 13-month-old wild-type and APPswe/PS1dE9 mice correlates well with capillary density measured with immunohistochemical staining. However, no differences in capillary density were detected between genotypes. The rCBVmicro values showed no significant correlation with amyloid-β (Aβ) plaque deposition, Aβ at blood vessel walls and biochemically measured levels of Aβ1-40, Aβ1-42 oligomers and fibrillar forms. These results suggest that rCBVmicro reduction is caused by an impaired vasoactivity of capillaries and arterioles, which is not directly correlated with the amount of Aβ deposition in parenchyma nor blood vessel walls.  相似文献   
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Background: Routine pathological examination can miss micro-metastatic tumor foci in the lymph nodes (LN) of patients with prostate cancer (PCa) that undergo radical prostatectomy and pelvic lymph node dissection (PLND). The aim of the present prospective study was to evaluate the impact of micrometastases assessed by serial section (SS), immunohistochemistry (IHC), and Real-time Polymerase Chain Reaction (RT-PCR) in patients undergoing radical prostatectomy with extended PLND. Materials and methods: 32 consecutive patients who underwent radical prostatectomy with extended PLND (obturator, internal/external and distal 2cm common iliac lymph-nodes (LN)) for intermediate (clinical T1c-T2 and PSA:10-20 ng/mL and clinical Gleason Score = 7) or high (clinical stage T3 or PSA>20 or clinical Gleason Score = 8-10) PCa were enrolled. The nodes were processed by the one uropathologist, both according to the routine pathological examination (analysis of the central section for 4 mm nodes or every 2 mm for LN>4 mm), which served as comparative method, both according to SS, IHC with antibodies against PSA and broad-spectrum Cytokeratins (BSCK), and quantitative RT-PCR targeting PSA, PSMA (PS Membrane Antigen), and Glucuronidase-S-Beta (GUSB) mRNA, that are over-expressed in prostatic cancer cells. Results: A total of 628 LN were analyzed, with a mean number of LN removed of 19.6 (SD = 7.2). Applying the routine pathological examination, 10 (31.2%) patients and 23 (3.9%) LN resulted positive for nodal involvement, with mean positive LN of 2.2 (SD = 1.4). After applying the SS and the molecular method of analysis (IHC and RT-PCR), micrometastases were found in 7 LN (SS showed micrometastases in 3 of them, IHC in 6 of them and RT-PCR in 7 of them); a total of 3 (9.3%) node-negative patients showed micrometastases at routine pathological examination (in 2 patients with RT-PCR and in 1 with IHC). Conclusions: The significance of micrometastases in PCa and the potential therapeutic role of PLND is not yet clarified, but the molecular analysis of the LN can detect a significant percentage of patients who harbor micro-metastatic PCa missed at routine pathological examination, and can enhance the accuracy of lymphadenectomy as a staging method.  相似文献   
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Objectives: The aim of this report is to present the results of a scanning electron microscopic study on the presence of matrix vesicles (MVs) found in human dentine. Study Design: Dentin tissue from 20 human bicuspids was analyzed by means of scanning electron microscopy. Results: MVs were found as outgrowths of the cellular membrane of the odontoblastic body, the more proximal portion of the odontoblastic process before entering the dentinal tubule and in the odontoblastic process within the inner third of the dentin. Size of MVs varied depending on location. In the inner third of dentin, they were seen in diverse positions; as membranal outgrowths, deriving from the odontoblastic process, lying free in the intratubular space and attached to the dentinal wall. Sometimes, they were seen organized forming groups of different sizes and shapes or as multivesicular chains running from the surface of the odontoblastic process to the tubular wall. MVs were present in places never considered: 1) the body of odontoblasts; 2) the most proximal part of the odontoblastic processes before entering the circumpulpal dentine and also: 3) in the inner third of dentinal tissue. Conclusions: According to our results, MVs not only participate during mantle dentin mineralization during early dentinogenesis, they also contribute during the mineralization process of the inner dentin. Key words:Dentin, microvesicles, secretory vesicles, dentin formation, dentin secretion.  相似文献   
40.
Objective: This exploratory study assessed health literacy among urban African-American high school students to improve understanding of the association between adolescent health literacy and asthma. Methods: We conducted a secondary data analysis of the control group (n = 181) of the Puff City randomized controlled trial (2006–2010), a web-based intervention to promote asthma management among students, grades 9 through 12. A validated self-report 3-item health literacy screening instrument was completed at final online follow-up survey. Logistic regression was used to explore the association between health literacy, demographic characteristics, quality of life, asthma management, and health care utilization. Results: Multivariate analysis revealed that an overall inadequate health literacy score was associated with students who were more likely to be younger (OR 0.61; 95% CI 0.44–0.84), not on Medicaid (OR 0.36; 95% CI 0.17–0.76), have at least one hospitalization (OR 1.29; 95% CI 1.07–1.56); and a lower overall quality of life (OR 0.75; 95% CI 0.59–0.95). Those lacking confidence in filling out medical forms, needing help reading hospital materials, and having difficulty understanding written information were more likely to not have a rescue inhaler (OR 0.49; 95% CI 0.25–0.94), have one or more emergency visits (OR 1.21 95% CI 1.02–1.43), and one or more hospitalizations (OR 1.19; 95% CI 1.01–1.41), respectively. Conclusions: The findings indicate a significant association between inadequate health literary and suboptimal asthma management. It is important to advance understanding of adolescent health literacy, especially those at-risk, as they assume asthma self-management tasks and move toward independent adult self-care.  相似文献   
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