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991.
Acute kidney injury(AKI) is increasingly prevalent in developing and developed countries and is associated with severe morbidity and mortality.Most etiologies of AKI can be prevented by interventions at the individual,community,regional and in-hospital levels.Effective measures must include community-wide efforts to increase an awareness of the devastating effects of AKI and provide guidance on preventive strategies,as well as early recognition and management.Efforts should be focused on minimizing causes of AKI,increasing awareness of the importance of serial measurements of serum creatinine in high risk patients,and documenting urine volume in acutely ill people to achieve early diagnosis;there is as yet no definitive role for alternative biomarkers.Protocols need to be developed to systematically manage prerenal conditions and specific infections.More accurate data about the true incidence and clinical impact of AKI will help to raise the importance of the disease in the community,increase awareness of AKI by governments,the public,general and family physicians and other health care professionals to help prevent the disease.Prevention is the key to avoid the heavy burden of mortality and morbidity associated with AKI.  相似文献   
992.
Background and aimsDiabetes is one of the global health emergencies of the 21st century. This study sought to assess self-care behaviours, glycaemic control and health-related quality of life (HRQoL) of type 2 diabetes patients at a Nigerian hospital, determine factors associated with HRQoL, and assess the inter-relationship among these outcomes.MethodsThe Summary of Diabetes Self-Care Activities (SDSCA) measure was used to assess self-care behaviours; HRQoL was assessed with the Appraisal of Diabetes Scale (ADS) and SF-12v2 Health Survey. Glycaemic control was assessed with fasting blood sugar (FBS). The questionnaires were distributed to 250 eligible patients attending Endocrinology clinic at the University of Uyo Teaching Hospital, Akwa Ibom State, Nigeria.ResultsMean scores (±SD) of self-care behaviours were 4.0 ± 1.3, 3.9 ± 1.0, 2.4 ± 1.2, 1.0 ± 1.1, and 2.5 ± 2.1 for general diet, specific diet, exercise, blood glucose monitoring, and foot care respectively. Mean FBS was 7.1 ± 2.1 mmol/L. Mean ADS score was 18.1 ± 4.2. The physical and mental component summary scores were 47.84 ± 8.21 and 45.66 ± 8.74 respectively. HRQoL was significantly associated with patient socio-demographic (except gender) and clinical variables (p < 0.05). Self-care activities, FBS and HRQoL were significantly inter-correlated (rs ?0.31 to 0.68; p < 0.01, p < 0.001).ConclusionsPatients were more adherent to diet recommendations than to other aspects of self-care. Though most patients had adequate glucose control, the presence of diabetes had a negative impact on the mental component of health. HRQoL was affected by most of the patient-related variables. Interventions to improve adherence to self-care are recommended to achieve good glycaemic control and improve HRQoL.  相似文献   
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Individuals with sickle cell anemia (SCA) have increased susceptibility to infections, secondary to impairment of immune function. Besides the described dysfunction in innate immunity, including impaired opsonization and phagocytosis of bacteria, evidence of dysfunction of T and B lymphocytes in SCA has also been reported. This includes reduction in the proportion of circulating CD4+ and CD8+ T cells, reduction of CD4+ helper: CD8+ suppressor T cell ratio, aberrant activation and dysfunction of regulatory T cells (Treg), skewing of CD4+ T cells towards Th2 response and loss of IgM‐secreting CD27 + IgMhighIgDlow memory B cells. These changes occur on the background of immune activation characterized by predominance of memory CD4+ T cell phenotypes, increased Th17 signaling and elevated levels of C‐reactive protein and pro‐inflammatory cytokines IL‐6 and TNF‐α, which may affect the immunogenicity and protective efficacy of vaccines available to prevent infections in SCA. Thus, in order to optimize the use of vaccines in SCA, a thorough understanding of T and B lymphocyte functions and vaccine reactivity among individuals with SCA is needed. Studies should be encouraged of different SCA populations, including sub‐Saharan Africa where the burden of SCA is highest. This article summarizes our current understanding of lymphocyte biology in SCA, and highlights areas that warrant future research. Am. J. Hematol. 91:938–946, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
996.
Recent advances in follicular lymphoma (FL) have resulted in prolongation of overall survival (OS). Here we assessed if early events as defined by event‐free survival (EFS) at 12 and 24 months from diagnosis (EFS12/EFS24) can inform subsequent OS in FL. 920 newly diagnosed grade 1‐3A FL patients enrolled on the University of Iowa/Mayo Clinic Lymphoma SPORE Molecular Epidemiology Resource (MER) from 2002‐2012 were initially evaluated. EFS was defined as time from diagnosis to progression, relapse, re‐treatment, or death due to any cause. OS was compared to age‐and‐sex‐matched survival in the general US population using standardized mortality ratios (SMR) and 95% confidence intervals (CI). We used a cohort of 412 FL patients from two Lyon, France hospital registries for independent replication. Patients who failed to achieve EFS12 had poor subsequent OS (MER SMR = 3.72, 95%CI: 2.78‐4.88; Lyon SMR = 8.74, 95%CI: 5.41‐13.36). Conversely, patients achieving EFS12 had no added mortality beyond the background population (MER SMR = 0.73, 95%CI: 0.56‐0.94, Lyon SMR = 1.02, 95%CI: 0.58‐1.65). Patients with early events after immunochemotherapy had especially poor outcomes (EFS12 failure: MER SMR = 17.63, 95%CI:11.97‐25.02, Lyon SMR = 19.10, 95%CI:9.86‐33.36; EFS24 failure: MER SMR = 13.02, 95%CI:9.31‐17.74, Lyon SMR = 7.22, 95%CI:4.13‐11.74). In a combined dataset of all patients from both cohorts, baseline FLIPI was no longer informative in EFS12 achievers. Reassessment of patient status at 12 months from diagnosis in follicular lymphoma patients, or at 24 months in patients treated with immunochemotherapy, is a strong predictor of subsequent overall survival in FL. Early event status provides a simple, clinically relevant endpoint for studies assessing outcome in FL. Am. J. Hematol. 91:1096–1101, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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OBJECTIVE: To investigate the molecular mechanism responsible for the reduced capacity of dendritic cells (DCs) from HLA-B27-transgenic rats to form conjugates with naive T cells. METHODS: We monitored interactions between DCs derived from HLA-B27-transgenic, HLA-B7-transgenic control, and nontransgenic rats and naive CD4+ T cells. Chemoattraction was studied in Transwell assays, and the formation of an immunologic synapse was examined by videomicroscopy and electron microscopy. Involvement of specific molecules in the defective interaction was examined in antibody-blocking assays. RESULTS: T cells migrated normally toward B27 DCs, but upon contact, the frequency of T cells undergoing a Ca2+ response was decreased, indicating impaired immunologic synapse formation. The immunologic synapse formed between B27 DCs and T cells appeared to be normal, as assessed by electron microscopy and by the Ca2+ response. Blocking lymphocyte function-associated antigen 1 on T cells or blocking activated leukocyte cell adhesion molecules on DCs inhibited an equivalent proportion of conjugates from forming between B27 or control DCs and T cells, whereas blocking CD86 on DCs and blocking CD28, CD2, or CD4 on T cells inhibited a greater number of conjugates from forming with control DCs, indicating specific involvement of costimulatory molecules in the reduced formation of conjugates with B27 DCs. Mature B27 molecules on the DC surface were responsible for this decreased formation of conjugates. CONCLUSION: In the HLA-B27-transgenic rat model of spondylarthropathy, mature B27 molecules expressed by DCs impair the formation of an antigen-independent immunologic synapse with naive CD4+ T cells by interfering with the engagement of costimulatory molecules. This phenomenon could potentially affect the production and/or maintenance of regulatory T cells and contribute to the expansion of pathogenic CD4+ T cells.  相似文献   
999.
BACKGROUND: The incremental role of bedside tissue Doppler echocardiography and B-type natriuretic peptide (BNP) over the clinical judgment has been recently reported in the emergency diagnosis of congestive heart failure with a normal left ventricular ejection fraction (HFNEF). However, how well does this diagnostic strategy be applicable in the setting of atrial fibrillation is unknown. OBJECTIVE: To investigate the usefulness of bedside tissue Doppler echocardiography and BNP in the emergency diagnosis of HFNEF in elderly patients with permanent, nonvalvular atrial fibrillation. METHODS: Forty-one consecutive elderly patients with an ejection fraction > or =50% (mean age 84 years; 22 with HFNEF and 19 with noncardiac cause), hospitalized for acute dyspnea at rest, were prospectively enrolled; bedside septal E/Ea and BNP were obtained at admission. Results: By multivariable logistic regression analysis including the clinical judgment of heart failure, E/Ea and BNP, E/Ea (P = 0.014) and BNP (P = 0.018) provided independent diagnostic information. Optimal cutoffs were 13 for E/Ea (area under the ROC curve of 0.846, P < 0.0001; sensitivity 81.8%, specificity 89.5%) and 253 pg/ml for BNP (area under the ROC curve of 0.928, P < 0.0001; sensitivity 86.4%, specificity 89.5%). The concordance between the clinical judgment and BNP concentration at the cutoff of 253 pg/ml correctly classified 24 of 25 patients; E/Ea at the cutoff of 13 correctly classified 14 of the 16 patients with discrepancy. CONCLUSION: Bedside tissue Doppler echocardiography and BNP provide useful additional diagnostic information over the clinical judgment for the emergency diagnosis of HFNEF in elderly patients with permanent, nonvalvular atrial fibrillation.  相似文献   
1000.

Background

Evidence exists for racial/ethnic differences in left ventricular mass index (LVMI). How this translates to future cardiovascular disease (CVD) events is unknown.

Hypothesis

The impact of racial/ethnic differences in LVMI on incident cardiovascular outcomes could have potential implications for the optimization of risk stratification strategies.

Methods

Using the prospectively collected database of the Multi‐Ethnic Study of Atherosclerosis (MESA) involving 4 racial/ethnic groups (non‐Hispanic Whites, Chinese, Blacks, and Hispanics) free of CVD at baseline, we assessed for racial/ethnic differences in the relationship between LVMI and incident CVD using a Cox model.

Results

5004 participants (mean age, 62 ± 10 years; 48% male) were included in this study. After an average follow‐up of 10.2 years, 369 (7.4%) CVD events occurred. Significant racial/ethnic differences existed in the relationship between LVMI and incident CVD (P for interaction = 0.04). Notably, the relationship was strongest for Chinese (HR per 10‐unit increase in LVMI: 1.7, 95% CI: 1.1–2.8) and Hispanics (HR per 10‐unit increase in LVMI: 1.9, 95% CI: 1.5–2.2). Non‐Hispanic Whites demonstrated the lowest relationship (HR: 1.3, 95% CI: 1.1–1.5). LVMI values of 36.9 g/m2.7, 31.8 g/m2.7, 39.9 g/m2.7, and 41.7 g/m2.7 were identified as optimal cutpoints for defining left ventricular hypertrophy (LVH) for non‐Hispanic Whites, Chinese, Blacks, and Hispanics, respectively. In secondary analysis of LVH (vs no LVH) using these optimal cutpoints, we found a similar pattern of association as above (P for interaction = 0.04). For example, compared with those without LVH, Chinese with LVH had HR: 5.3, 95% CI: 1.6–17, whereas non‐Hispanic Whites with LVH had HR: 1.6, 95% CI: 1.2–2.1 for CVD events.

Conclusions

Among 4 races/ethnicities studied, LVMI has more prognostic utility predicting future CVD events for Chinese and Hispanics and is least significant for non‐Hispanic Whites.  相似文献   
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