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991.
BackgroundNew marker-based criteria for the diagnosis of Alzheimer's disease (AD) were recently proposed. We describe their operational translation in 144 consecutive patients referred to our Memory Clinic.MethodsVisual ratings of hippocampal atrophy and of cortical glucose hypometabolism in magnetic resonance imaging and positron emission tomography, and concentrations of total tau and Aβ1-42 in cerebrospinal fluid were assessed in 12 patients with subjective memory complaints (SMCs) (Mini-Mental State Examination [MMSE] score, 28.0 ± 1.1 [mean ± SD]), 37 with mild cognitive impairment (MCI) (MMSE, 25.1 ± 3.6), 55 with AD (MMSE, 21.1 ± 3.5), and 40 with non-AD dementia (MMSE, 21.6 ± 5.5).ResultsThe sensitivity for AD of each individual biomarker was higher (65% to 87%) than for MCI (18% to 50%). Each biomarker's specificity for SMC and non-AD dementias was good to moderate (83% and 53%). Positivity for at least one marker increased the probability 38 times of belonging to the AD group (P < 0.0001).ConclusionThe new diagnostic criteria can be operationalized in clinical routines, but longitudinal studies of MCI patients will need to assess the criteria's prognostic value.  相似文献   
992.
This study evaluated the usefulness of electrospray mass spectrometry to distinguish sera of early-stage pancreatic cancer patients from disease-free individuals. Sera peak data were generated from 33 pancreatic cancer patients and 30 disease-free individuals. A "leave one out" cross-validation procedure discriminated stage I/II pancreatic cancer versus disease-free sera with a p value <.001 and a receiver-operator characteristic curve area value of 0.85. Predictive values for cancer stage I/II test efficiency, specificity, and sensitivity were 78%, 77%, and 79%, respectively. These studies indicate that electrospray mass spectrometry is useful for distinguishing sera of early-stage pancreatic cancer patients from disease-free individuals.  相似文献   
993.

Introduction

Schwannomas are usually benign nerve sheath tumors, which typically arise in the head, neck, spinal cord and extremities. Schwannoma of the biliary tract is an extremely rare finding. Patients generally lack symptoms and seek medical attention when tumor growth causes obstructive jaundice. Preoperative diagnosis is difficult and resection is the treatment of choice.

Methods

A 54 year-old female with history of back and right labia minor melanoma for which she underwent complete excision and right inguinal lymph node dissection more than 10 years ago, was evaluated for new onset gastroesophageal reflux symptoms and found to have markedly abnormal liver enzymes. Imagining studies revealed intrahepatic ductal dilatation and a 5.2 cm mass in the porta hepatis that was not consistent with cholangiocarcinoma or hepatocellular carcinoma. Multiple percutaneous biopsies of the mass failed to provide a definitive diagnosis. With a high clinical suspicion of metastatic melanoma and no other evident sites of disease, operative intervention was undertaken for diagnosis and definitive treatment.

Results

Diagnostic laparoscopy was performed initially, but access to the mass was difficult, given its location. Subsequently, the patient underwent laparotomy, with tumor excision, common bile duct resection and hepato-jejunostomy. Pathologic examination and analysis were consistent with cellular schwannoma. Postoperatively, the patient recovered uneventfully, and liver function studies returned to normal.

Conclusion

Schwannomas are uncommon tumors, which very rarely arise from the biliary tract and cause biliary obstruction. Exploration is indicated in order to establish the diagnosis and to render definitive treatment.  相似文献   
994.
Behavioral couples therapy (BCT) is an evidence-based family treatment for substance abuse. The results of numerous investigations over the past 30 years indicate that participation in this treatment by married or cohabiting substance-abusing patients, compared with more traditional individual-based interventions, results in greater reductions in substance use, higher levels of relationship satisfaction, greater reductions in partner violence, and more favorable cost outcomes. This review examines the rationale for using BCT, the empirical literature supporting its use, methods used as part of this intervention, and future research directions.  相似文献   
995.
Cognitive-behavioral therapy (CBT), because of its comparatively high level of cognitive demand, is likely to be challenging for substance users with limitations in cognitive function. However, it is not known whether computer-assisted versions of CBT will be particularly helpful (e.g., allowing individualized pace and repetition) or difficult (e.g., via complexity of computerized delivery) for such patients. In this secondary analysis of data collected from a randomized clinical trial evaluating computer-assisted CBT, four aspects of cognitive functioning were evaluated among 77 participants. Those with higher levels of risk taking completed fewer sessions and homework assignments and had poorer substance use outcomes.  相似文献   
996.
Aging is a physiologic state in which a progressive decline of organ functions may be accompanied by developing age-related diseases and neurodegenerative diseases. The causes of such conditions remain unknown, being probably related to a multifactor process. To date, the Free Radical and Mitochondrial theories seem to be the two most prominent that could explain both how and why aged people develop certain disorders, providing a rationale for treatment. Several reports demonstrate that mitochondria play a key role in aging and some neurodegenerative diseases. Damaged mitochondria produce increased amounts of Reactive Oxygen Species (ROS), leading, in turn, to progressive augmentation in damage. Dysfunctional mitochondria enhance susceptibility to cell death. Indeed, at cell level mitochondria act as an energetic hub determining cell final fate through caspase-dependent apoptosis. Thus, if aging results from oxidative stress, it may be corrected by environmental, nutritional and pharmacological strategies. In this review we summarize the role of mitochondria dysfunction occurring in aging and neurodegenerative disease, describing novel mitochondria-targeted therapy approach and the new selective molecules and nanocarriers technology as potentially effective in targeting mitochondrial dysfunction.  相似文献   
997.
998.
To identify therapeutic opportunities for oncolytic viral therapy, we conducted genome-wide RNAi screens to search for host factors that modulate rhabdoviral oncolysis. Our screens uncovered the endoplasmic reticulum (ER) stress response pathways as important modulators of rhabdovirus-mediated cytotoxicity. Further investigation revealed an unconventional mechanism whereby ER stress response inhibition preconditioned cancer cells, which sensitized them to caspase-2-dependent apoptosis induced by a subsequent rhabdovirus infection. Importantly, this mechanism was tumor cell specific, selectively increasing potency of the oncolytic virus by up to 10,000-fold. In?vivo studies using a small molecule inhibitor of IRE1α showed dramatically improved oncolytic efficacy in resistant tumor models. Our study demonstrates proof of concept for using functional genomics to improve biotherapeutic agents for cancer.  相似文献   
999.
Cetuximab is a chimeric monoclonal antibody for the epidermal growth factor receptor (EGFR) that may provide benefit to select cancer patients; however, identification of the characteristics of those patients who may benefit from its use is not complete. The ChemoFx? drug response marker (DRM) is an in vitro assay that can provide drug response data on tumor specimens before any patient treatment is initiated. We determined the feasibility of using the ChemoFx DRM to test tumor samples for sensitivity to cetuximab. We exposed four non-small cell lung carcinoma (NSCLC) cell lines (H358, H520, HCC827, and H1666) to cetuximab and determined their sensitivity using the ChemoFx DRM and, in parallel, EGFR status using immunocytochemistry, Western blotting, and In-Cell Western (TM) analysis. We used the ChemoFx DRM to determine cetuximab sensitivity of primary NSCLC and colorectal tumor samples. The ChemoFx DRM distinguished between cetuximab-sensitive and -resistant cell lines. Cetuximab sensitivity was not dependent on EGFR mutational status; H358 cells were non-responsive to cetuximab yet contain wild-type EGFR, whereas H1666 cells were intermediately responsive to cetuximab and contain wild-type EGFR. HCC827 (EGFR-mutant) cells were intermediately responsive and, as expected, H520 cells (EGFR-null) were non-responsive to cetuximab. ChemoFx-determined cetuximab sensitivity of primary NSCLC and colorectal tumor samples was 9.0% and 7.5%, respectively. Use of the ChemoFx DRM is feasible for determining cetuximab sensitivity. The ChemoFx-determined cetuximab responses of primary NSCLC and colorectal tumor specimens were similar to published response rates of patients to treatment with cetuximab monotherapy.  相似文献   
1000.
Clinical trials operations struggle to achieve optimal distribution of workload in a dynamic data management and regulatory environment, and to achieve adequate cost recovery for personnel costs. The University of Michigan Comprehensive Cancer Center developed and implemented an effort tracking application to quantify data management and regulatory workload to more effectively assess and allocate work while improving charge capture. Staff recorded how much time they spend each day performing specific study-related and general office tasks. Aggregated data on staff use of the application from 2006 through 2009 were analyzed to gain a better understanding of what trial characteristics require the most data management and regulatory effort. Analysis revealed 4 major determinants of staff effort: 1) study volume (actual accrual), 2) study accrual rate, 3) study enrollment status, and 4) study sponsor type. Effort tracking also confirms that trials that accrued at a faster rate used fewer resources on a per-patient basis than slow-accruing trials. In general, industry-sponsored trials required the most data management and regulatory support, outweighing other sponsor types. Although it is widely assumed that most data management efforts are expended while a trial is actively accruing, the authors learned that 25% to 30% of a data manager's effort is expended while the study is either not yet open or closed to enrollment. Through the use of a data-driven effort tracking tool, clinical research operations can more efficiently allocate workload and ensure that study budgets are negotiated to adequately cover study-related expenses.  相似文献   
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