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61.
62.
Patients with amyotrophic lateral sclerosis (ALS) have a motor disorder and cognitive difficulties, including difficulty with action verbs. However, the basis for the action verb impairment is unknown. Thirty-six participants with ALS and 22 with Parkinson’s disease (PD) were assessed on a simple, two-alternative forced-choice associativity judgment task, where performance was untimed and did not depend on motor functioning. We probed 120 frequency-matched action verbs, cognition verbs, concrete nouns and abstract nouns. Performance was related to T1 MRI imaging of gray matter atrophy. Patients with ALS were significantly impaired relative to healthy senior control participants only for action verbs. Patients with PD did not differ from controls for all word categories. Regression analyses related action verb performance in ALS to motor-associated cortices, but action verb judgments in PD were not related to cortical atrophy. These findings are consistent with the hypothesis that action verb difficulty in ALS is related in part to the degradation of action-related conceptual knowledge represented in motor-associated cortex.  相似文献   
63.
Supraspinal processes in humans can have a top‐down enhancing effect on nociceptive processing in the brain and spinal cord. Studies have begun to suggest that such influences occur in conditions such as fibromyalgia (FM), but it is not clear whether this is unique to FM pain or common to other forms of chronic pain, such as that associated with osteoarthritis (OA). We assessed top‐down processes by measuring anticipation‐evoked potentials and their estimated sources, just prior (< 500 ms) to laser heat pain stimulation, in 16 patients with FM, 16 patients with OA and 15 healthy participants, by using whole‐brain statistical parametric mapping. Clinical pain and psychological coping factors (pain catastrophizing, anxiety, and depression) were well matched between the patient groups, such that these did not confound our comparisons between FM and OA patients. For the same level of heat pain, insula activity was significantly higher in FM patients than in the other two groups during anticipation, and correlated with the intensity and extent of reported clinical pain. However, the same anticipatory insula activity also correlated with OA pain, and with the number of tender points across the two patient groups, suggesting common central mechanisms of tenderness. Activation in the dorsolateral prefrontal cortex was reduced during anticipation in both patient groups, and was related to less effective psychological coping. Our findings suggest common neural correlates of pain and tenderness in FM and OA that are enhanced in FM but not unique to this condition.  相似文献   
64.
Ipsilateral primary motor cortex (M1) reorganisation after unilateral lower‐limb amputation may degrade function of the amputated limb. We hypothesised unilateral lower‐limb amputees would have a bilateral increase in corticomotor excitability, and increased excitability of ipsilateral M1 would be associated with increased step‐time variability during gait. Twenty transtibial amputees (16 male) aged 60.1 years (range 45–80 years), and 20 age‐ and gender‐matched healthy adult controls were recruited. Single‐pulse transcranial magnetic stimulation assessed corticomotor excitability. Two indices of corticomotor excitability were calculated. An index of corticospinal excitability (ICE) determined relative excitability of ipsilateral and contralateral corticomotor projections to alpha‐motoneurons innervating the quadriceps muscle (QM) of the amputated limb. A laterality index (LI) assessed relative excitability of contralateral projections from each hemisphere. Spatial‐temporal gait analysis was performed to calculate step‐time variability. Amputees had lower ICE values, indicating relatively greater excitability of ipsilateral corticomotor projections than controls (= 0.04). A lower ICE value was associated with increased step‐time variability for amputated (= 0.04) and non‐amputated limbs (= 0.02). This association suggests corticomotor projections from ipsilateral M1 to alpha‐motoneurons innervating the amputated limb QM may interfere with gait. Cortical excitability in amputees was not increased bilaterally, contrary to our hypothesis. There was no difference in excitability of contralateral M1 between amputees and controls (= 0.10), and no difference in LI (= 0.71). It appears both hemispheres control one QM, with predominance of contralateral corticomotor excitability in healthy adults. Following lower‐limb amputation, putative ipsilateral corticomotor excitability is relatively increased in some amputees and may negatively impact on function.  相似文献   
65.
Introduction: Magnetic resonance imaging of muscle shows short tau‐inversion recovery (STIR) brightness in autosomal dominant facioscapulohumeral muscular dystrophy (FSHD1) suggestive of active inflammation/injury. We measured the longitudinal stability/progression of this potential disease biomarker. Methods: Nine subjects underwent calf MRI imaging over 2 years. Two radiologists evaluated qualitative muscle changes. Results: In 3/9 subjects, calf muscles demonstrated moderate/severe STIR hyperintensity at Time 1 that had progressed to fatty replacement 2 years later (Time 2). In the remaining subjects, moderate/severe muscle STIR abnormalities, when present, were consistent between exams. Mild STIR+ elevations had roughly similar patterns between exams. Conclusions: Moderate/severe STIR hyperintensities often foreshadow fatty replacement over a 2‐year interval. Whether longer time courses are required to observe muscle degeneration and fatty replacement in some subjects remains to be explored. Muscle Nerve 49 : 257–260, 2014  相似文献   
66.

Objective

Patients with terminal illness often face important medical decisions that may carry ethical and legal implications, yet they may be at increased risk for impaired decisional capacity. This study examined the prevalence of impairment on the four domains of decisional capacity relevant to existing legal standards.

Method

Twenty-four adults diagnosed with a terminal illness completed the MacArthur Competence Assessment Tool for Treatment, a semi-structured measure of decision-making capacity and measures of cognitive functioning and psychological distress.

Results

Approximately one third of the sample demonstrated serious impairment on at least one domain of decisional capacity. The greatest proportion of impairment was found on subscales that rely heavily on verbal abilities. Decisional capacity was significantly associated with cognitive functioning and education, but not with symptoms of anxiety or depression.

Conclusions

This study is the first to examine decisional capacity in patients with terminal illness relative to legal standards of competence. Although not universal, decisional impairment was common. Clinicians working with terminally ill patients should frequently assess capacity as these individuals are called on to make important medical decisions. Comprehensive assessment will aid clinicians in their responsibility to balance respect for patient autonomy with their responsibility to protect patients from harm resulting from impaired decisional capacity.  相似文献   
67.
This contemporary review of melanoma surveillance strategies seeks to help practitioners examine and improve their surveillance protocols based on the currently available data. In general, there is no definitive benefit from increased screening or more aggressive use of interval imaging. Low-intensity surveillance strategies do not appear to adversely affect patient outcomes and should be the preferred approach compared with high-intensity strategies for most melanoma patients. All surveillance programs should emphasize education in order to maximize the effectiveness of patient-based detection of recurrent disease.  相似文献   
68.
ObjectivesIn patients with a rising prostate-specific antigen (PSA) level during treatment with androgen deprivation therapy, identification of men who progress to bone metastasis and death remains problematic. Accurate risk stratification models are needed to better predict risk for bone metastasis and death among patients with castration-resistant prostate cancer (CRPC). This study evaluates whether alkaline phosphatase (AP) kinetics predicts bone metastasis and death in patients with CRPC.Methods and materialsA retrospective cohort study of 9,547 patients who underwent treatment for prostate cancer was conducted using the Center for Prostate Disease Research Multi-center National Database. From the entire cohort, 347 were found to have CRPC and, of those, 165 had 2 or more AP measurements during follow-up. To determine the AP velocity (APV), the slope of the linear regression line of all AP values was plotted over time. Rapid APV was defined as the uppermost quartile of APV values, which was found to be ≥6.3 IU/l/y. CRPC was defined as 2 consecutive rising PSA values after achieving a PSA nadir<4 ng/ml and documented testosterone values less than 50 ng/dl. The primary study outcomes included bone metastasis–free survival (BMFS) and overall survival (OS).ResultsRapid APV and PSA doubling time (PSADT) less than 10 months were strong predictors of both BMFS and OS in a multivariable analysis. Faster PSADT was a stronger predictor for BMFS (odds ratio [OR] = 12.1, P<0.0001 vs. OR = 2.7, P = 0.011), whereas rapid APV was a stronger predictor of poorer OS (OR = 5.11, P = 0.0001 vs. OR = 3.98, P = 0.0034). In those with both a rapid APV and a faster PSADT, the odds of developing bone metastasis and death exceeded 50%.ConclusionAPV is an independent predictor of OS and BMFS in patients with CRPC. APV, in conjunction with PSA-based clinical parameters, may be used to better identify patients with CRPC who are at the highest risk of metastasis and death. These findings need validation in prospective studies.  相似文献   
69.
ObjectivesTreating high-risk prostate cancer (CaP) with definitive therapy improves survival. We evaluated whether having health insurance reduces racial disparities in the use of definitive therapy for high-risk CaP.Materials and methodsThe Surveillance, Epidemiology, and End Results Program was used to identify 70,006 men with localized high-risk CaP (prostate-specific antigen level >20 ng/ml or Gleason score 8–10 or stage>cT3a) diagnosed from 2007 to 2010. We used multivariable logistic regression to analyze the 64,277 patients with complete data to determine the factors associated with receipt of definitive therapy.ResultsCompared with white men, African American (AA) men were significantly less likely to receive definitive treatment (adjusted odds ratio [AOR] = 0.60; 95% CI: 0.56–0.64; P<0.001) after adjusting for sociodemographics and known CaP prognostic factors. There was a significant interaction between race and insurance status (Pinteraction = 0.01) such that insurance coverage was associated with a reduction in racial disparity between AA and white patients regarding receipt of definitive therapy. Specifically, the AOR for definitive treatment for AA vs. white was 0.38 (95% CI: 0.27–0.54, P<0.001) among uninsured men, whereas the AOR was 0.62 (95% CI: 0.57–0.66, P<0.001) among insured men.ConclusionsAA men with high-risk CaP were significantly less likely to receive potentially life-saving definitive treatment when compared with white men. Having health insurance was associated with a reduction in this racial treatment disparity, suggesting that expansion of health insurance coverage may help reduce racial disparities in the management of aggressive cancers.  相似文献   
70.
ObjectivesCigarette smoking is a known risk factor for urothelial carcinoma (UC) of the bladder. However, the persistence of an increased risk for UC following smoking cessation is not well established. We assessed the risk of UC among former smokers using a recent, prospective cohort with a high proportion of former smokers.Materials and methodsStudy participants were members of the VITamins And Lifestyle cohort (VITAL), a group of 77,719 men and women between the ages of 50 and 76 years from western Washington State. Smoking history and other risk factors were obtained at the time of recruitment. The primary outcome was a new diagnosis of UC (n =385), as determined through linkage to a population-based cancer registry.Results and limitationsThe cohort included 8% current and 44% former smokers, and among the UC cases, 15% were current and 60% former smokers. Both the current and former smoker had an increased risk of UC compared with never smokers (hazard ratio [HRs]: 3.81; 95% confidence intervals [CI] 2.71–5.35 and 2.0; 95% CI 1.55–2.58, respectively). Among former smokers, the risk of UC increased with the pack-years smoked and decreased with the years since quitting. When both the measures of smoking were considered together, the risk of UC was similar for long-term quitters and recent quitters for a given level of pack-years. For example, for those with pack-years of 22.5–37.5, the HR of UC was 1.91 (95% CI 1.17–3.11) for the distant quitters (≥23.5 y before baseline) and HR = 1.92 (95% CI 1.26–2.94) among the recent quitters. Limitations include the small number of cases at the extremes of smoking history and errors in self-reported smoking history.ConclusionsThe risk of bladder cancer in former smokers remains elevated>32 years after quitting, even among those with moderate smoking histories. This argues that a history of smoking confers a lifelong increased risk of UC.  相似文献   
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