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Mild traumatic brain injury (TBI) is a common source of morbidity from the wars in Iraq and Afghanistan. With no overt lesions on structural MRI, diagnosis of chronic mild TBI in military veterans relies on obtaining an accurate history and assessment of behavioral symptoms that are also associated with frequent comorbid disorders, particularly posttraumatic stress disorder (PTSD) and depression. Military veterans from Iraq and Afghanistan with mild TBI (n = 30) with comorbid PTSD and depression and non‐TBI participants from primary (n = 42) and confirmatory (n = 28) control groups were assessed with high angular resolution diffusion imaging (HARDI). White matter‐specific registration followed by whole‐brain voxelwise analysis of crossing fibers provided separate partial volume fractions reflecting the integrity of primary fibers and secondary (crossing) fibers. Loss of white matter integrity in primary fibers (P < 0.05; corrected) was associated with chronic mild TBI in a widely distributed pattern of major fiber bundles and smaller peripheral tracts including the corpus callosum (genu, body, and splenium), forceps minor, forceps major, superior and posterior corona radiata, internal capsule, superior longitudinal fasciculus, and others. Distributed loss of white matter integrity correlated with duration of loss of consciousness and most notably with “feeling dazed or confused,” but not diagnosis of PTSD or depressive symptoms. This widespread spatial extent of white matter damage has typically been reported in moderate to severe TBI. The diffuse loss of white matter integrity appears consistent with systemic mechanisms of damage shared by blast‐ and impact‐related mild TBI that involves a cascade of inflammatory and neurochemical events. Hum Brain Mapp 34:2986–2999, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
14.

Purpose

To externally validate the performance characteristics of the Briganti’s risk stratification tool for baseline staging bone scan in patients with newly diagnosed prostate cancer (PCa).

Methods

From 2009 onwards, a consecutive series of patients with PCa were enrolled. All patients were staged to evaluate the presence of bone metastasis (BM) with a conventional total-body Tc 99 m MDP scintigraphy performed regardless of baseline PCa characteristics. The area under the curve (AUC) estimates were used to test the accuracy of the Briganti’s risk stratification tool that recommended staging baseline bone scan for patients with a biopsy Gleason score >7 or with a prostate-specific antigen (PSA) >10 ng/ml and palpable disease (cT2/T3). The new tool was compared to the European Association of Urology (EAU) guideline.

Results

A total of 313 patients were consecutively enrolled. Median age was 68 (range 49–95 years), and median PSA was 7 ng/ml (range 0.81–2,670). Twenty (6.4 %) patients presented BMs. Patients with BMs were significantly older, with higher PSA and a higher Gleason score (p = 0.001). The novel Briganti’s model was significantly (p = 0.001) more accurate (AUC: 0.75; CI: 0.632–0.859) than the EAU guideline (AUC: 0.64; CI: 0.52–0.761) for the prediction of BMs.

Conclusions

Our study validated in a group of patients with PCa the novel risk stratification tool proposed by Briganti, which presented a higher accuracy for baseline staging bone scan when compared with the EAU guideline. In our experience, this approach would further reduce (about 60 %) the use of staging baseline bone scan without compromising the ability to detect BMs in patients with PCa.  相似文献   
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Purpose

Sympathetic nervous system (SNS) hyperactivity is a salient characteristic of chronic heart failure (HF) and contributes to the progression of the disease. Iodine-123 meta-iodobenzylguanidine (123I-mIBG) imaging has been successfully used to assess cardiac SNS activity in HF patients and to predict prognosis. Importantly, SNS hyperactivity characterizes also physiological ageing, and there is conflicting evidence on cardiac 123I-mIBG uptake in healthy elderly subjects compared to adults. However, little data are available on the impact of ageing on cardiac sympathetic nerve activity assessed by 123I-mIBG scintigraphy, in patients with HF.

Methods and results

We studied 180 HF patients (age?=?66.1?±?10.5 years [yrs]), left ventricular ejection fraction (LVEF?=?30.6?±?6.3 %) undergoing cardiac 123I-mIBG imaging. Early and late heart to mediastinum (H/M) ratios and washout rate were calculated in all patients. Demographic, clinical, and echocardiographic data were also collected. Our study population consisted of 53 patients aged >75 years (age?=?77.7?±?4.0 year), 67 patients aged 62–72 years (age?=?67.9?±?3.2 years) and 60 patients aged ≤61 year (age?=?53.9?±?5.6 years). In elderly patients, both early and late H/M ratios were significantly lower compared to younger patients (p?<?0.05). By multivariate analysis, H/M ratios (both early and late) and washout rate were significantly correlated with LVEF and age.

Conclusions

Our data indicate that, in a population of HF patients, there is an independent age-related effect on cardiac SNS innervation assessed by 123I-mIBG imaging. This finding suggests that cardiac 123I-mIBG uptake in patients with HF might be affected by patient age.
  相似文献   
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Background

Adjacent segment disease (ASDz) is a potential complication following lumbar spinal fusion. A common nomenclature based on etiology and ASDz type does not exist and is needed to assist with clinical prognostication, decision making, and management.

Questions/Purposes

The objective of this study was to develop an etiology-based classification system for ASDz following lumbar fusion.

Methods

We conducted a retrospective chart review of 65 consecutive patients who had undergone both a lumbar fusion performed by a single surgeon and a subsequent procedure for ASDz. We established an etiology-based classification system for lumbar ASDz with the following six categories: “degenerative” (degenerative disc disease or spondylosis), “neurologic” (disc herniation, stenosis), “instability” (spondylolisthesis, rotatory subluxation), “deformity” (scoliosis, kyphosis), “complex” (fracture, infection), or “combined.” Based on this scheme, we determined the rate of ASDz in each etiologic category.

Results

Of the 65 patients, 27 (41.5%) underwent surgery for neurogenic claudication or radiculopathy for adjacent-level stenosis or disc herniation and were classified as “neurologic.” Ten patients (15.4%) had progressive degenerative disc pathology at the adjacent level and were classified as “degenerative.” Ten patients (15.4%) had spondylolisthesis or instability and were classified as “instability,” and three patients (4.6%) required revision surgery for adjacent-level kyphosis or scoliosis and were classified as “deformity.” Fifteen patients (23.1%) had multiple diagnoses that included a combination of categories and were classified as “combined.”

Conclusion

This is the first study to propose an etiology-based classification scheme of ASDz following lumbar spine fusion. This simple classification system may allow for the grouping and standardization of patients with similar pathologies and thus for more specific pre-operative diagnoses, personalized treatments, and improved outcome analyses.

  相似文献   
19.

Objectives:

To assess the effectiveness of school-based interventions program in reducing the prevalence of overweight or obesity among schoolchildren.

Data source:

Ovid Medline (1950-December 2012), Embase (1980-2012), CINAHL (1982-2012), secondary references, review articles, and expert in the field.

Study selection:

All published clinical trials were eligible for study if were randomized, methodologically strong-based on a validity assessment, aimed to evaluate a school-based intervention for childhood overweight or obesity, and measured outcome in term of prevalence/incidence difference in overweight and obesity among both groups. Studies involved in cost-effective analysis of school-based intervention have been excluded. Data from eligible studies abstracted and pooled for relative risk.

Results:

Five trials with 3,904 schoolchildren were included. Mean age of the students (boys and girls) ranges 8.6-12.6 years. Meta-analysis showed a statistical significance beneficial effect of school-based intervention programs on obesity status of schoolchildren (risk ratio (RR) 0.58, 95% confidence interval (CI) 0.43-0.78) and suggested 42% reduction in prevalence of obesity among schoolchildren through school-based intervention programs. Individual studies also showed effectiveness of these school-based interventions.

Conclusion:

School-based intervention programs are effective in prevention of childhood overweight and obesity problem and our results quantitatively supported this argument.  相似文献   
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