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Magnetic resonance imaging (MRI) is the current gold standard for the diagnosis of brain tumors. However, despite the development of MRI techniques, the differential diagnosis of central nervous system (CNS) primary pathologies, such as lymphoma and glioblastoma or tumor‐like brain lesions and glioma, is often challenging. MRI can be supported by in vivo magnetic resonance spectroscopy (MRS) to enhance its diagnostic power and multiproject‐multicenter evaluations of classification of brain tumors have shown that an accuracy around 90% can be achieved for most of the pairwise discrimination problems. However, the survival rate for patients affected by gliomas is still low. The High‐Resolution Magic‐Angle‐Spinning Nuclear Magnetic Resonance (HR‐MAS NMR) metabolomics studies may be helpful for the discrimination of gliomas grades and the development of new strategies for clinical intervention. Here, we propose to use T2‐filtered, diffusion‐filtered and conventional water‐presaturated spectra to try to extract as much information as possible, fusing the data gathered by these different NMR experiments and applying a chemometric approach based on Multivariate Curve Resolution (MCR). Biomarkers important for glioma's discrimination were found. In particular, we focused our attention on cystathionine (Cyst) that shows promise as a biomarker for the better prognosis of glioma tumors.  相似文献   
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MR metabolic profiling of the prostate is promising as an additional diagnostic approach to separate indolent from aggressive prostate cancer. The objective of this study was to assess the relationship between the Gleason score and the metabolic biomarker (choline + creatine + spermine)/citrate (CCS/C) measured by ex vivo high‐resolution magic angle spinning MRS (HR‐MAS MRS) and in vivo MRSI, and to evaluate the correlation between in vivo‐ and ex vivo‐measured metabolite ratios from spatially matched prostate regions. Patients (n = 13) underwent in vivo MRSI prior to radical prostatectomy. A prostate tissue slice was snap‐frozen shortly after surgery and the locations of tissue samples (n = 40) collected for ex vivo HR‐MAS were matched to in vivo MRSI voxels (n = 40). In vivo MRSI was performed on a 3T clinical MR system and ex vivo HR‐MAS on a 14.1T magnet. Relative metabolite concentrations were calculated by LCModel fitting of in vivo spectra and by peak integration of ex vivo spectra. Spearman's rank correlations (ρ) between CCS/C from in vivo and ex vivo MR spectra, and with their corresponding Gleason score, were calculated. There was a strong positive correlation between the Gleason score and CCS/C measured both in vivo and ex vivo (ρ = 0.77 and ρ = 0.69, respectively; p < 0.001), and between in vivo and ex vivo metabolite ratios from spatially matched regions (ρ = 0.67, p < 0.001). Our data indicate that MR metabolic profiling is a potentially useful tool for the assessment of cancer aggressiveness. Moreover, the good correlation between in vivo‐ and ex vivo‐measured CCS/C demonstrates that our method is able to bridge MRSI and HR‐MAS molecular analysis. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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High‐resolution magic angle spinning (HR MAS) nuclear magnetic resonance (NMR) spectroscopy is increasingly being used to study metabolite levels in human breast cancer tissue, assessing, for instance, correlations with prognostic factors, survival outcome or therapeutic response. However, the impact of intratumoral heterogeneity on metabolite levels in breast tumor tissue has not been studied comprehensively. More specifically, when biopsy material is analyzed, it remains questionable whether one biopsy is representative of the entire tumor. Therefore, multi‐core sampling (n = 6) of tumor tissue from three patients with breast cancer, followed by lipid (0.9‐ and 1.3‐ppm signals) and metabolite quantification using HR MAS 1H NMR, was performed, resulting in the quantification of 32 metabolites. The mean relative standard deviation across all metabolites for the six tumor cores sampled from each of the three tumors ranged from 0.48 to 0.74. This was considerably higher when compared with a morphologically more homogeneous tissue type, here represented by murine liver (0.16–0.20). Despite the seemingly high variability observed within the tumor tissue, a random forest classifier trained on the original sample set (training set) was, with one exception, able to correctly predict the tumor identity of an independent series of cores (test set) that were additionally sampled from the same three tumors and analyzed blindly. Moreover, significant differences between the tumors were identified using one‐way analysis of variance (ANOVA), indicating that the intertumoral differences for many metabolites were larger than the intratumoral differences for these three tumors. That intertumoral differences, on average, were larger than intratumoral differences was further supported by the analysis of duplicate tissue cores from 15 additional breast tumors. In summary, despite the observed intratumoral variability, the results of the present study suggest that the analysis of one, or a few, replicates per tumor may be acceptable, and supports the feasibility of performing reliable analyses of patient tissue.  相似文献   
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The prognosis for patients with pancreatic cancer is extremely poor, as evidenced by the disease's five‐year survival rate of ~5%. New approaches are therefore urgently needed to improve detection, treatment, and monitoring of pancreatic cancer. MRS‐detectable metabolic changes provide useful biomarkers for tumor detection and response‐monitoring in other cancers. The goal of this study was to identify MRS‐detectable biomarkers of pancreatic cancer that could enhance currently available imaging approaches. We used 1H high‐resolution magic angle spinning MRS to probe metabolite levels in pancreatic tissue samples from mouse models and patients. In mice, the levels of lipids dropped significantly in pancreata with lipopolysaccharide‐induced inflammation, in pancreata with pre‐cancerous metaplasia (4 week old p48‐Cre;LSL‐KrasG12D mice), and in pancreata with pancreatic intraepithelial neoplasia, which precedes invasive pancreatic cancer (8 week old p48‐Cre LSL‐KrasG12D mice), to 26 ± 19% (p = 0.03), 19 ± 16% (p = 0.04), and 26 ± 10% (p = 0.05) of controls, respectively. Lactate and taurine remained unchanged in inflammation and in pre‐cancerous metaplasia but increased significantly in pancreatic intraepithelial neoplasia to 266 ± 61% (p = 0.0001) and 999 ± 174% (p < 0.00001) of controls, respectively. Importantly, analysis of patient biopsies was consistent with the mouse findings. Lipids dropped in pancreatitis and in invasive cancer biopsies to 29 ± 15% (p = 0.01) and 26 ± 38% (p = 0.02) of normal tissue. In addition, lactate and taurine levels remained unchanged in inflammation but rose in tumor samples to 244 ± 155% (p = 0.02) and 188 ± 67% (p = 0.02), respectively, compared with normal tissue. Based on these findings, we propose that a drop in lipid levels could serve to inform on pancreatitis and cancer‐associated inflammation, whereas elevated lactate and taurine could serve to identify the presence of pancreatic intraepithelial neoplasia and invasive tumor. Our findings may help enhance current imaging methods to improve early pancreatic cancer detection and monitoring. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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ObjectiveTo investigate the associations between participants’ adherence to a physical activity and exercise program after stroke and functional recovery 18 months after inclusion.DesignSecondary analyses of the intervention arm in the multisite randomized controlled trial Life After Stroke (LAST).SettingPrimary health care services in 3 Norwegian municipalities.ParticipantsOf the participants enrolled (N=380), 186 (48.9%) were randomized to the intervention. The study sample comprised community dwelling individuals included 3 months after stroke, with mean age of 71.7 ± 11.9 years and 82 (44.1%) women. According to the National Institutes of Health Stroke Scale, 97.3% were diagnosed as having mild (National Institutes of Health Stroke Scale<8) and 2.7% with moderate (8-16 on the National Institutes of Health Stroke Scale) stroke.InterventionMonthly coaching by physiotherapists encouraging participants to adhere to 30 minutes of daily physical activity and 45-60 minutes of weekly exercise.Main Outcome MeasuresThe primary outcome was Motor Assessment Scale (MAS). Secondary outcome measures were 6-minute walk test, Timed Up and Go (TUG), Berg Balance Scale (BBS), and the physical domains of the Stroke Impact Scale (SIS). Adherence was assessed by combining participants’ training diaries and physiotherapists’ reports.ResultsThe relationship between adherence and functional recovery was analyzed with simple and multiple linear regression models. Adjusted for age, sex, dependency, and cognition, results showed statistically significant associations between adherence and functional outcomes after 18 months, as measured by MAS, TUG, BBS, and SIS (P≤.026).ConclusionsIncreased adherence to physical activity and exercise was associated with improved functional recovery after mild to moderate stroke. This emphasizes the importance of developing adherence-enhancing interventions. Dose-response studies are recommended for future research.  相似文献   
8.

Objective

To compare the efficacy of neuromuscular electrical stimulation (NMES) and transcutaneous nerve stimulation (TENS) on hemiplegic shoulder pain (HSP).

Design

This is a prospective randomized controlled trial.

Setting

A rehabilitation hospital.

Participants

Participants (N=90) were randomized into NMES (n=36), TENS (n=36), or control groups (n=18).

Interventions

NMES (15Hz, pulse width 200μs) was applied to supraspinatus and deltoids (medial and posterior parts), whereas TENS (100Hz, pulse width 100μs) was used on the same areas. The surface electrodes were placed near the motor points of the supraspinatus and medial or posterior bundle of deltoids. The 4-week treatment consisted of 20 sessions, each session composed of 1 hour of stimulation per day. Routine rehabilitation program without any stimulation was administered to the control and the NMES/TENS groups. Numerical rating scale (NRS), active/passive range of motion (AROM/PROM) of shoulder, upper extremity Fugl-Meyer Assessment (FMA), modified Ashworth scale (MAS), Barthel Index (BI), and stroke-specific quality of life scale (SSQOLS) were assessed in a blinded manner at baseline, 2, 4, and 8 weeks after treatment, respectively.

Main Outcome Measures

The primary endpoint was the improvement from baseline in NRS for HSP at 4 weeks.

Results

NRS scores in NMES, TENS, and control groups had decreased by 2.03, 1.44, and 0.61 points, respectively after 4 weeks of treatment, with statistically significant differences among the 3 groups (P<.001). The efficacy of the NMES group was significantly better than that of the TENS group (P=.043). Moreover, the efficacy of NMES and TENS groups was superior to that of the control group (P<.001, P=.044, respectively). The differences in the therapeutic efficacy on shoulder AROM/PROM, FMA, MAS, BI, and SSQOLS scores were not significant among the 3 groups.

Conclusions

TENS and NMES can effectively improve HSP, the efficacy of NMES being distinctly superior to that of TENS in maintaining long-term analgesia. However, NMES was not more efficacious than the TENS or control group in improving the shoulder joint mobility, upper limb function, spasticity, the ability of daily life activity, and stroke-specific quality of life in HSP patients.  相似文献   
9.
Juvenile dermatomyositis is an immune-mediated inflammatory multi-system disease involving mainly striated muscles and skin. Typical dermatological features are fundamental to establish the diagnosis, especially whenever the myopathy is very mild or absent, as it occurs in the form called as amyopathic juvenile dermatomyositis. Sometimes, systemic rheumatic diseases can develop a hyperferritinemia syndrome characterized by hemophagocytosis, namely macrophage activation syndrome, which represents a severe and life-threatening complication. Here, we describe a complex clinical history characterized by a hyper-ferritinemia syndrome after infectious mononucleosis, leading to recurrent episodes of macrophage activation syndrome. Finally, the late onset of several skin changes brought to a diagnosis of amyopathic juvenile dermatomyositis.  相似文献   
10.
ObjectivesTo evaluate change in fine motor hand performance and to investigate the relationship between existing clinical measures and dynamic computerized dynamometry (DCD) after botulinum toxin-A (BTX-A) injections for adults with upper limb spasticity.DesignPretest/posttest clinical intervention study.SettingHospital outpatient spasticity clinics.ParticipantsA convenience sample of adults (N=28; mean age, 51y) with upper limb spasticity after acquired brain injury.InterventionsBTX-A injections for upper limb spasticity management.Main Outcome MeasuresDCD protocol using a piezoelectric pinch meter (termed DCD[pinch]); current clinical upper limb measures: Modified Ashworth Scale, Tardieu Scale, Action Research Arm Test, Michigan Hand Outcomes Questionnaire, and Goal Attainment Scale.ResultsBTX-A produced a significant change on DCD(pinch) and some current clinical measures, with correlations observed between DCD(pinch) and current clinical measures.ConclusionsDCD(pinch) sensitively and objectively assessed the effects of BTX-A on upper limb spasticity during a simulated functionally based pinch and release task.  相似文献   
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