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101.
Although there are clear interactions between circadian rhythms and drug addiction, mechanisms for such interactions remain unknown. Here we establish a role for the Clock gene in regulating the brain's reward circuit. Mice lacking a functional Clock gene display an increase in cocaine reward and in the excitability of dopamine neurons in the midbrain ventral tegmental area, a key brain reward region. These phenotypes are associated with increased expression and phosphorylation of tyrosine hydroxylase (the rate-limiting enzyme in dopamine synthesis), as well as changes in several genes known to regulate dopamine activity in the ventral tegmental area. These findings demonstrate the involvement of a circadian-associated gene, Clock, in regulating dopamine function and cocaine reward.  相似文献   
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Background

Treatment‐related mortality and abandonment of therapy are major barriers to successful treatment of childhood acute lymphoblastic leukemia (ALL) in the developing world.

Procedure

A collaboration was undertaken between Instituto Nacional de Cancerologia (Bogota, Colombia), which serves a poor patient population in an upper‐middle income country, and Dana‐Farber/Boston Children's Cancer and Blood Disorders Center (Boston, USA). Several interventions aimed at reducing toxic deaths and abandonment were implemented, including a reduced‐intensity treatment regimen and a psychosocial effort targeting abandonment. We performed a cohort study to assess impact.

Results

The Study Population comprised 99 children with ALL diagnosed between 2007 and 2010, and the Historic Cohort comprised 181 children treated prior to the study interventions (1995–2004). Significant improvements were achieved in the rate of deaths in complete remission (13% to 3%; P = 0.005), abandonment (32% to 9%; P < 0.001), and event‐free survival with abandonment considered an event (47% to 65% at 2 years; P = 0.016). However, relapse rate did not improve. Medically unnecessary treatment delays were common, and landmark analysis revealed that initiating the PIII phase of therapy ≥4 weeks delayed predicted markedly inferior disease‐free survival (P = 0.016). Conversely, patients who received therapy without excessive delays had outcomes approaching those achieved in high‐income countries.

Conclusions

Implementation of a twinning program was followed by reductions in abandonment and toxic deaths, but relapse rate did not improve. Inappropriate treatment delays were common and strongly predicted treatment failure. These findings highlight the importance of adherence to treatment schedule for effective therapy of ALL. Pediatr Blood Cancer 2015;62:1395–1402. © 2015 Wiley Periodicals, Inc.  相似文献   
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Healthcare institutions, accreditation agencies for higher learning, and organizations such as the National Academy of Medicine in the United States, support interprofessional education (IPE) opportunities. However, incorporating IPE opportunities into academic settings remains difficult. One challenge is assessing IPE learning and practice outcomes, especially at the level of student performance to ensure graduates are “collaboration-ready”. The Creighton-Interprofessional Collaborative Evaluation (C-ICE) instrument was developed to address the need for a measurement tool for interprofessional student team performance. Four interprofessional competency domains provide the framework for the C-ICE instrument. Twenty-six items were identified as essential to include in the C-ICE instrument. This instrument was found to be both a reliable and a valid instrument to measure interprofessional interactions of student teams. Inter-rater reliability as measured by Krippendorff’s nominal alpha (nKALPHA) ranged from .558 to .887; with four of the five independent assessments achieving nKALPHA greater than or equal to 0.796. The findings indicated that the instrument is understandable (Gwet’s alpha coefficient (gAC) 0.63), comprehensive (gAC = 0.62), useful and applicable (gAC = 0.54) in a variety of educational settings. The C-ICE instrument provides educators a comprehensive evaluation tool for assessing student team behaviors, skills, and performance.  相似文献   
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OBJECTIVES: We sought to determine pregnancy outcomes in patients with tetralogy of Fallot (TOF). BACKGROUND: Pregnancy outcomes in patients with TOF are incompletely defined. METHODS: Clinical, hemodynamic, and obstetric data were reviewed for women with TOF and prior pregnancy. RESULTS: Of 72 respondents, 43 (mean age, 26 years) had 112 pregnancies (range, 1 to 5); 82 pregnancies were successful. Eight women had unrepaired TOF at the time of their 20 successful pregnancies. At first assessment (age > or =18 years), six patients had pulmonary hypertension, three had moderate or severe right ventricular (RV) systolic dysfunction, and 13 had severe RV dilation due to pulmonic regurgitation. Sixteen patients had 30 miscarriages (27%) and one term stillbirth. Mean overall birth weight was 3.2 kg (range, 2.1 to 4.2 kg). Unrepaired TOF (p = 0.05) and morphologic pulmonary artery abnormality (p = 0.03) were independently predictive of infant birth weight. Six patients had cardiovascular complications during pregnancy: supraventricular tachycardia in two, heart failure in two, pulmonary embolism in a patient with pulmonary hypertension, and progressive RV dilation in a patient with severe pulmonic regurgitation. Five infants (6%) had congenital anomalies. CONCLUSIONS: Patients with TOF have an increased risk of fetal loss, and their offspring are more likely to have congenital anomalies than offspring in the general population. Adverse maternal events, although rare, may be associated with left ventricular dysfunction, severe pulmonary hypertension, and severe pulmonic regurgitation with RV dysfunction.  相似文献   
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Activity of lactosyl ceramide beta-galactosidase (beta-D-galactoside galactohydrolase, EC 3.2.1.23) was found to be extremely low in enzyme preparations from liver, brain, and cultured skin fibroblasts from patients with Krabbe's disease. Leukocytes from one set of parents had enzyme levels approximately half those measured in control leukocytes. The low activity observed for this galactolipid hydrolase is the fourth enzymatic deficiency noted for this genetic disease. Beta-galactosidase activity toward galactocerebroside, psychosine, and monogalactosyl diglyceride is also low in patients with Krabbe's disease. Other lysosomal enzymes measured were found to be in the normal range. This enzymatic defect may provide a better explanation for the pathological and chemical findings previously reported for this syndrome.  相似文献   
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