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141.
142.
We describe a patient who developed a systemic lupus erythematosus-like syndrome characterized by bilateral malar erythema, antinuclear antibody, and anti-double-stranded DNA antibody. He was started on hemodialysis (3 times/week) because of renal failure. He completely lacked total hemolytic complement (CH50) activity, which was subsequently determined to be due to the absence of the first component of complement (C1). The specificity was further defined, by Ouchterlony analysis using anti-C1s antiserum, and was found to be the C1 subcomponent C1s. There was no absence of C1r. We conclude that this is a case of selective deficiency of C1s.  相似文献   
143.
The Native American Pima population has the highest incidence of insulin resistance (IR) and type 2 diabetes mellitus (T2DM) of any reported population, but the pathophysiologic mechanism is unknown. Genetic studies in Pima Indians have linked acyl-CoA dehydrogenase 10 (ACAD10) gene polymorphisms, among others, to this predisposition. The gene codes for a protein with a C-terminus region that is structurally similar to members of a family of flavoenzymes—the acyl-CoA dehydrogenases (ACADs)—that catalyze α,β-dehydrogenation reactions, including the first step in mitochondrial FAO (FAO), and intermediary reactions in amino acids catabolism. Dysregulation of FAO and an increase in plasma acylcarnitines are recognized as important in the pathophysiology of IR and T2DM. To investigate the deficiency of ACAD10 as a monogenic risk factor for T2DM in human, an Acad-deficient mouse was generated and characterized. The deficient mice exhibit an abnormal glucose tolerance test and elevated insulin levels. Blood acylcarnitine analysis shows an increase in long-chain species in the older mice. Nonspecific variable pattern of elevated short-terminal branch-chain acylcarnitines in a variety of tissues was also observed. Acad10 mice accumulate excess abdominal adipose tissue, develop an early inflammatory liver process, exhibit fasting rhabdomyolysis, and have abnormal skeletal muscle mitochondria. Our results identify Acad10 as a genetic determinant of T2DM in mice and provide a model to further investigate genetic determinants for insulin resistance in humans.  相似文献   
144.

Background

In this study we evaluated the influence of sex on the left ventricular end-diastolic dimension (LVEDD) and adverse outcomes in patients hospitalized for acute decompensated heart failure (HF) with a reduced ejection fraction (EF).

Methods

Among the 4842 patients enrolled in the Acute Decompensated Heart Failure Syndromes (ATTEND) registry, 2367 patients (1607 men and 760 women) discharged alive after hospitalization for acute decompensated HF with a reduced EF (defined as a left ventricular EF < 50%) were investigated to assess the association of sex and LVEDD with the primary end point (all-cause death and readmission for HF after discharge). Men and women were separately divided into LVEDD quartiles at discharge (men: LVEDD ≤ 54, 55-60, 61-65, and ≥ 66 mm; women: LVEDD ≤ 48, 49-54, 55-60, and ≥ 61 mm). The median follow-up period after discharge was 524 (range, 385-785) days.

Results

Occurrence of the primary end point did not differ between men and women (37.0% vs 37.2%; P = 0.921). After adjustment for multiple comorbidities including left ventricular EF, men with an LVEDD of 61-65 and ≥ 66 mm had a significantly higher risk of the primary end point than men with an LVEDD ≤ 54 mm, indicating a positive association between a larger LVEDD and adverse outcomes. In contrast, in women, the adjusted risk of the primary end point was comparable among the LVEDD quartiles.

Conclusions

Men and women with acute decompensated HF and a reduced EF might show important differences in relation to the association between left ventricular cavity dilation and outcomes.  相似文献   
145.

Background

Acute heart failure (AHF) with its high in-hospital mortality is an increasing burden on healthcare systems worldwide, and comparing hospital performance is required for improving hospital management efficiency. However, it is difficult to distinguish patient severity from individual hospital care effects. The aim of this study was to develop a risk adjustment model to predict in-hospital mortality for AHF using routinely available administrative data.

Methods

Administrative data were extracted from 86 acute care hospitals in Japan. We identified 8620 hospitalized patients with AHF from April 2010 to March 2011. Multivariable logistic regression analyses were conducted to analyze various patient factors that might affect mortality. Two predictive models (models 1 and 2; without and with New York Heart Association functional class, respectively) were developed and bootstrapping was used for internal validation. Expected mortality rates were then calculated for each hospital by applying model 2.

Results

The overall in-hospital mortality rate was 7.1%. Factors independently associated with higher in-hospital mortality included advanced age, New York Heart Association class, and severe respiratory failure. In contrast, comorbid hypertension, ischemic heart disease, and atrial fibrillation/flutter were found to be associated with lower in-hospital mortality. Both model 1 and model 2 demonstrated good discrimination with c-statistics of 0.76 (95% confidence interval, 0.74-0.78) and 0.80 (95% confidence interval, 0.78-0.82), respectively, and good calibration after bootstrap correction, with better results in model 2.

Conclusions

Factors identifiable from administrative data were able to accurately predict in-hospital mortality. Application of our model might facilitate risk adjustment for AHF and can contribute to hospital evaluations.  相似文献   
146.
Background Although hepatitis C virus (HCV) infection is a persistent public health concern in hemodialysis patients, there seem to have been only a few reports on the prevalence of HCV at the start of hemodialysis. In this study we investigated whether patients starting on hemodialysis therapy are positive for anti-HCV antibody or not. Methods The 400 patients who began regular hemodialysis between February 2003 and June 2007 were enrolled in this study. Clinical data such as age, anti-HCV antibody and primary cause of end-stage kidney disease (ESKD) were examined. As healthy controls we used 70,717 healthy blood donors in 2005 whose data were obtained from Tokyo Metropolitan Red Cross Blood Center. Anti-HCV antibody was used as an indicator of HCV infection. Since the prevalence of HCV infection is affected by age in Japan, we classified the patients by age group. Results The anti-HCV antibody prevalence rate among the patients who were new to hemodialysis was 7.3%, as opposed to 0.15% in the healthy volunteers. The prevalence of HCV in the 31–45-, 46–60-, and 61-year-old groups was significantly higher among the hemodialysis patients than among the healthy volunteers (P = 0.0209, <0.0001, and <0.0001, respectively). The prevalence rate of anti-HCV antibody was higher among men (10.0%) than among women (1.5%, P < 0.0001) in the hemodialysis patients. The anti-HCV-antibody-positive patients were significantly older than the anti-HCV-antibody-negative patients (66.4 ± 14.3 years versus 58.6±16.6 years; P = 0.0152). Diabetic nephropathy was a more frequent cause of ESKD among the anti-HCV-antibody-positive patients (30.4%) than among the anti-HCV-antibody-negative patients (19.9%, P = 0.0122). Among the anti-HCV-antibody-positive patients, 55.2% had received a blood transfusion. The rate was significantly higher than that among the anti-HCV-antibody-negative patients (19.4%, P < 0.0001). Conclusion The results showed a much higher rate of anti-HCV antibody positivity in patients new to hemodialysis than in healthy volunteers. Older age, blood transfusion, male gender, and diabetic nephropathy seemed to be risk factors for anti-HCV antibody positivity in Japan.  相似文献   
147.
BACKGROUND: A child whose left temporal lobe contained mesial, anterior and basal structures but lacked superio-lateral cortex had intractable epilepsy secondary to a porencephalic cyst. Magnetoencephalography (MEG) shows equivalent current dipoles (ECDs) as dipole modeling for temporal lobe epilepsy rather than in an exact location. AIM: We hypothesized that the magnetic fields generated by the epileptic discharges in mesio-basal temporal areas could be detected by MEG without interference from the superio-lateral temporal cortices. METHODS: We analyzed MEG spikes using single dipole analysis and synthetic aperture magnetometry (SAM), and compared with EEG spike topography. RESULTS: Two MEG ECDs corresponding to T3 spikes localized to the anterior mesio-basal temporal region with vertical orientation. Sixteen MEG ECDs corresponding to T5 spikes localized to the middle to posterior mesio-basal temporal region with vertical orientation. SAM revealed maximum current density at hippocampus and anterior fusiform gyrus for T3 spikes, and at posterior hippocampus and fusiform gyrus for T5 spikes. CONCLUSION: Vertically oriented ECDs were obtained without superio-lateral temporal cortices because of temporo-parieto-occipital porencephalic cyst. The absence of superio-lateral temporal cortices, prominent temporal EEG spikes, less prominent MEG spikes, and mesio-basal SAM spikes indicated that the vertically oriented ECDs were projected directly from the mesio-basal temporal region.  相似文献   
148.
PURPOSE: To identify the predictors of postsurgical seizure freedom in children with refractory epilepsy and normal or nonfocal MRI findings. METHODS: We analyzed 22 children with normal or subtle and nonfocal MRI findings, who underwent surgery for intractable epilepsy following extraoperative intracranial EEG. We compared clinical profiles, neurophysiological data (scalp EEG, magnetoencephalography (MEG) and intracranial EEG), completeness of surgical resection and pathology to postoperative seizure outcomes. RESULTS: Seventeen children (77%) had a good postsurgical outcome (defined as Engel class IIIA or better), which included eight (36%) seizure-free children. All children with postsurgical seizure freedom had an MEG cluster in the final resection area. Postsurgical seizure freedom was obtained in none of the children who had bilateral MEG dipole clusters (3) or only scattered dipoles (1). All five children in whom ictal onset zones were confined to < or = 5 adjacent intracranial electrodes achieved seizure freedom compared to three of 17 children with ictal onset zones that extended over >5 electrodes (p = 0.002). None of six children with more than one type of seizure became seizure-free, compared to eight of 16 children with a single seizure type (p = 0.04). Complete resection of the preoperatively localized epileptogenic zone resulted in seizure remission in 63% (5/8) and incomplete resections, in 21% (3/14) (p = 0.06). Age of onset, duration of epilepsy, number of lobes involved in resection, and pathology failed to correlate with seizure freedom. CONCLUSIONS: Surgery for intractable epilepsy in children with normal MRI findings provided good postsurgical outcomes in the majority of our patients. As well, restricted ictal onset zone predicted postoperative seizure freedom. Postoperative seizure freedom was less likely to occur in children with bilateral MEG dipole clusters or only scattered dipoles, multiple seizure types and incomplete resection of the proposed epileptogenic zone. Seizure freedom was most likely to occur when there was concordance between EEG and MEG localization and least likely to occur when these results were divergent.  相似文献   
149.
Objectives: The aim of this study was to develop a limited sampling strategy (LSS) for monitoring the use of mycophenolic acid (MPA) in maintenance therapy with tacrolimus (TCL) in renal transplant patients. Methods: Eighteen adult patients receiving a first transplant were investigated. All patients were treated with a combination of TCL, steroid and mycophenolate mofetil (MMF). Besides the predose trough concentration (C0), whole blood samples were taken for measurement of the MPA concentration at 0·5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12 h for a 14‐point 12‐h pharmacokinetic (PK) profile. Using stepwise linear regression analysis, an abbreviated area under the concentration time curve (AUC) was calculated using all 14, and any combination of sampling points to give an estimating equation with up to three predictors. Results: The equation derived from C2, C7 and C12, for AUC estimation: AUC = (2·05 × C2) + (8·51 ×C7) + (2·29 × C12) + 4·24. was found to be optimal. Using this formula, there was an excellent correlation between the estimated 3‐point AUC and AUC0–12 h. To assess the agreement between the abbreviated methods and the full PK profile, we plotted the average AUC of the abbreviated estimates and the full PK profile. This Bland‐Altman analysis indicated good agreement to within ±2 SD and a prediction variability of 7·56 μg × h/mL. Conclusion: Our proposed three‐sampling‐point estimate of AUCs is clinically acceptable. However, the sampling times are inconvenient for outpatients, and is recommended only for monitoring MMF treatment of inpatients with suspected toxicity or at high risk of organ rejection.  相似文献   
150.
Macrophage migration inhibitory factor plays an important role in inflammatory diseases. We investigated the role of macrophage migration inhibitory factor (MIF) in the development of dextran sulfate sodium (DSS)-induced colitis using MIF null ((-/-)) mice. MIF(-/-) mice given 3% DSS showed no clinical and histological feature of colitis in contrast to wild-type (WT) mice. Lack of MIF suppressed the up-regulation of TNF-alpha and IFN-gamma as Th1-derived cytokines, and increased the level of IL-4 as Th2-derived cytokine in the colon tissues. Moreover, we found that the expressions of heat shock protein (HSP)40 and HSP70 were markedly up-regulated in the colon of MIF(-/-) mice in response to DSS compared with WT mice. Additionally, quercetin, an inhibitor of HSP synthesis, inhibited the up-regulation of HSP40 and 70 expressions and developed DSS-induced colitis in MIF(-/-) mice. Our findings in this study provide more information in the role of MIF in colitis.  相似文献   
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