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891.

Background

Individuals with anorexia nervosa are thought to exert excessive self-control to inhibit primary drives.

Methods

This study used functional MRI (fMRI) to interrogate interactions between the neural correlates of cognitive control and motivational processes in the brain reward system during the anticipation of monetary reward and reward-related feedback. In order to avoid confounding effects of undernutrition, we studied female participants recovered from anorexia nervosa and closely matched healthy female controls. The fMRI analysis (including node-to-node functional connectivity) followed a region of interest approach based on models of the brain reward system and cognitive control regions implicated in anorexia nervosa: the ventral striatum, medial orbitofrontal cortex (mOFC) and dorsolateral prefrontal cortex (DLPFC).

Results

We included 30 recovered patients and 30 controls in our study. There were no behavioural differences and no differences in hemodynamic responses of the ventral striatum and the mOFC in the 2 phases of the task. However, relative to controls, recovered patients showed elevated DLPFC activity during the anticipation phase, failed to deactivate this region during the feedback phase and displayed greater functional coupling between the DLPFC and mOFC. Recovered patients also had stronger associations than controls between anticipation-related DLPFC responses and instrumental responding.

Limitations

The results we obtained using monetary stimuli might not generalize to other forms of reward.

Conclusion

Unaltered neural responses in ventral limbic reward networks but increased recruitment of and connectivity with lateral–frontal brain circuitry in recovered patients suggests an elevated degree of self-regulatory processes in response to rewarding stimuli. An imbalance between brain systems subserving bottom–up and top–down processes may be a trait marker of the disorder.  相似文献   
892.

Background

Previous studies have reported MRI abnormalities of the corpus callosum (CC) in patients with bipolar disorder (BD), although only a few studies have directly compared callosal areas in psychotic versus nonpsychotic patients with this disorder. We sought to compare regional callosal areas in a large international multicentre sample of patients with BD and healthy controls.

Methods

We analyzed anatomic T1 MRI data of patients with BD-I and healthy controls recruited from 4 sites (France, Germany, Ireland and the United States). We obtained the mid-sagittal areas of 7 CC subregions using an automatic CC delineation. Differences in regional callosal areas between patients and controls were compared using linear mixed models (adjusting for age, sex, handedness, brain volume, history of alcohol abuse/dependence, lithium or antipsychotic medication status, symptomatic status and site) and multiple comparisons correction. We also compared regional areas of the CC between patients with BD with and without a history of psychotic features.

Results

We included 172 patients and 146 controls in our study. Patients with BD had smaller adjusted mid-sagittal CC areas than controls along the posterior body, the isthmus and the splenium of the CC. Patients with a positive history of psychotic features had greater adjusted area of the rostral CC region than those without a history of psychotic features.

Limitations

We found small to medium effect sizes, and there was no calibration technique among the sites.

Conclusion

Our results suggest that BD with psychosis is associated with a different pattern of interhemispheric connectivity than BD without psychosis and could be considered a relevant neuroimaging subtype of BD.  相似文献   
893.
894.
Multifocal breast cancer (MFBC), defined as multiple synchronous unilateral lesions of invasive breast cancer, is relatively frequent and has been associated with more aggressive features than unifocal cancer. Here, we aimed to investigate the genomic heterogeneity between MFBC lesions sharing similar histopathological parameters. Characterization of different lesions from 36 patients with ductal MFBC involved the identification of non‐silent coding mutations in 360 protein‐coding genes (171 tumour and 36 matched normal samples). We selected only patients with lesions presenting the same grade, ER, and HER2 status. Mutations were classified as ‘oncogenic’ in the case of recurrent substitutions reported in COSMIC or truncating mutations affecting tumour suppressor genes. All mutations identified in a given patient were further interrogated in all samples from that patient through deep resequencing using an orthogonal platform. Whole‐genome rearrangement screen was further conducted in 8/36 patients. Twenty‐four patients (67%) had substitutions/indels shared by all their lesions, of which 11 carried the same mutations in all lesions, and 13 had lesions with both common and private mutations. Three‐quarters of those 24 patients shared oncogenic variants. The remaining 12 patients (33%) did not share any substitution/indels, with inter‐lesion heterogeneity observed for oncogenic mutation(s) in genes such as PIK3CA, TP53, GATA3, and PTEN. Genomically heterogeneous lesions tended to be further apart in the mammary gland than homogeneous lesions. Genome‐wide analyses of a limited number of patients identified a common somatic background in all studied MFBCs, including those with no mutation in common between the lesions. To conclude, as the number of molecular targeted therapies increases and trials driven by genomic screening are ongoing, our findings highlight the presence of genomic inter‐lesion heterogeneity in one‐third, despite similar pathological features. This implies that deeper molecular characterization of all MFBC lesions is warranted for the adequate management of those cancers. © 2015 The Authors. Pathological Society of Great Britain and Ireland.  相似文献   
895.

Objectives

The aim of this study was to develop a new scoring system based on thoracic aortic calcification (TAC) to predict 1-year cardiovascular and all-cause mortality.

Background

A calcified aorta is often associated with poor prognosis after transcatheter aortic valve replacement (TAVR). A risk score encompassing aortic calcification may be valuable in identifying poor TAVR responders.

Methods

The C4CAPRI (4 Cities for Assessing CAlcification PRognostic Impact) multicenter study included a training cohort (1,425 patients treated using TAVR between 2010 and 2014) and a contemporary test cohort (311 patients treated in 2015). TAC was measured by computed tomography pre-TAVR. CAPRI risk scores were based on the linear predictors of Cox models including TAC in addition to comorbidities and demographic, atherosclerotic disease and cardiac function factors. CAPRI scores were constructed and tested in 2 independent cohorts.

Results

Cardiovascular and all-cause mortality at 1 year was 13.0% and 17.9%, respectively, in the training cohort and 8.2% and 11.8% in the test cohort. The inclusion of TAC in the model improved prediction: 1-cm3 increase in TAC was associated with a 6% increase in cardiovascular mortality and a 4% increase in all-cause mortality. The predicted and observed survival probabilities were highly correlated (slopes >0.9 for both cardiovascular and all-cause mortality). The model’s predictive power was fair (AUC 68% [95% confidence interval [CI]: 64% to 72%]) for both cardiovascular and all-cause mortality. The model performed similarly in the training and test cohorts.

Conclusions

The CAPRI score, which combines the TAC variable with classical prognostic factors, is predictive of 1-year cardiovascular and all-cause mortality. Its predictive performance was confirmed in an independent contemporary cohort. CAPRI scores are highly relevant to current practice and strengthen the evidence base for decision making in valvular interventions. Its routine use may help prevent futile procedures.  相似文献   
896.
Objective: The Finnegan scoring list (FSL) is widely used to screen for poor neonatal adaptation in infants exposed to anti-depressants in utero. However, the large number of FSL-items and differential weighing of each item is time consuming. The aim of this study was to shorten and simplify the FSL yet preserving its clinimetric properties.

Methods: This observational study examined infants exposed to an anti-depressant during pregnancy admitted for at least 72?h on a maternity ward. Trained nurses completed the FSL three times daily. Items for the adapted FSL were selected through forward analysis whereby the number of selected items was based on the area under the curve (AUC). Internal validity was assessed by cross-validation.

Results: 183 infants met the inclusion criteria. By forward analysis eight equally-weighed items resulted in an AUC of 0.91. In cross-validation, the mean AUC was 0.89 for 8 items. This adapted FSL had a sensitivity of 97.7% and specificity of 37.0% and a sensitivity of 41.9% and specificity of 86.2% regarding a cut-off of, respectively, 1 and 2.

Conclusions: An adapted FSL with eight equally-weighed items has acceptable clinimetric properties and can serve as an easy to apply screening tool in infants exposed to anti-depressants during pregnancy.  相似文献   

897.
The non-invasive tension-time index of the inspiratory muscles at rest (TTMUS) can be used for assessing respiratory muscle function in children with cystic fibrosis (CF). This study aimed to investigate how TTMUS becomes altered with increasing pulmonary impairment, and which factors determine TTMUS changes in CF. We assessed TTMUS in 47 patients with stable CF ranging in age from 9 to 26 years and in 47 controls of same age and gender. Pulmonary impairment was assessed by the pulmonary function score (PFS) according to Cropp (PFS 0-2 = no, 3-7 = mild, 8-12 = moderate, and 13-18 = severe dysfunction). Median TTMUS was significantly higher in the entire CF-group than in controls ((0.112 (0.079-0.174) vs. 0.07 (0.052-0.094), P < 0.001)). It was nearly identical in CF-patients without (0.079 (0.056-0.114)) and mild (0.080 (0.059-0.128)) pulmonary dysfunction. It was non-significantly higher in subjects with moderate (0.118 (0.103-0.173)) and grossly elevated in individuals with severe (0.232 (0.211-0.31), P < 0.001)) respiratory impairment when compared to the other PFS-groups. TTMUS was significantly related to percent predicted airway resistance (Raw%pred) (r = 0.60, P < 0.001), percent predicted Forced Expiratory Volume in 1 sec (r = -0.49, P < 0.001), percent predicted Vital Capacity (-0.57, P < 0.001), Functional Residual Capacity in percent Total Lung Capacity (r = 0.42, P = 0.003), and transcutaneous oxygen saturation (r = -0.49, P < 0.001). By contrast, Raw%pred was the only variable that had a significant effect on TTMUS (P = 0.01), when a multivariate logistic regression was applied, using the median of the entire CF-cohort to dichotomise TTMUS. These findings suggest that subjects with stable CF and severe pulmonary dysfunction are prone to respiratory muscle fatigue, and that airway obstruction is an important factor contributing to the increase of TTMUS in CF. Regular determination of TTMUS may be clinically useful during course of disease, and may aid the decision to institute therapies like respiratory muscle training or non-invasive intermittent ventilation.  相似文献   
898.
Anti‐tumor efficacy of targeted peptide‐receptor radionuclide therapy (PRRT) relies on several factors, including functional tumor vasculature. Little is known about the effect of PRRT on tumor vasculature. With dynamic contrast‐enhanced (DCE‐) MRI, functional vasculature is imaged and quantified using contrast agents. In small animals DCE‐MRI is a challenging application. We optimized a clinical sequence for fast hemodynamic acquisitions, time‐resolved imaging of contrast kinetics (TRICKS), to obtain DCE‐MRI images at both high spatial and high temporal resolution in mice and rats. Using TRICKS, functional vasculature was measured prior to PRRT and longitudinally to investigate the effect of treatment on tumor vascular characteristics. Nude mice bearing H69 tumor xenografts and rats bearing syngeneic CA20948 tumors were used to study perfusion following PRRT administration with 177lutetium octreotate. Both semi‐quantitative and quantitative parameters were calculated. Treatment efficacy was measured by tumor‐size reduction. Optimized TRICKS enabled MRI at 0.032 mm3 voxel size with a temporal resolution of less than 5 s and large volume coverage, a substantial improvement over routine pre‐clinical DCE‐MRI studies. Tumor response to therapy was reflected in changes in tumor perfusion/permeability parameters. The H69 tumor model showed pronounced changes in DCE‐derived parameters following PRRT. The rat CA20948 tumor model showed more heterogeneity in both treatment outcome and perfusion parameters. TRICKS enabled the acquisition of DCE‐MRI at both high temporal resolution (Tres) and spatial resolutions relevant for small animal tumor models. With the high Tres enabled by TRICKS, accurate pharmacokinetic data modeling was feasible. DCE‐MRI parameters revealed changes over time and showed a clear relationship between tumor size and Ktrans. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
899.
Mitochondrial aldehyde dehydrogenase 2 (ALDH2) in the liver removes toxic aldehydes including acetaldehyde, an intermediate of ethanol metabolism. Nearly 40% of East Asians inherit an inactive ALDH2*2 variant, which has a lysine-for-glutamate substitution at position 487 (E487K), and show a characteristic alcohol flush reaction after drinking and a higher risk for gastrointestinal cancers. Here we report the characterization of knockin mice in which the ALDH2(E487K) mutation is inserted into the endogenous murine Aldh2 locus. These mutants recapitulate essentially all human phenotypes including impaired clearance of acetaldehyde, increased sensitivity to acute or chronic alcohol-induced toxicity, and reduced ALDH2 expression due to a dominant-negative effect of the mutation. When treated with a chemical carcinogen, these mutants exhibit increased DNA damage response in hepatocytes, pronounced liver injury, and accelerated development of hepatocellular carcinoma (HCC). Importantly, ALDH2 protein levels are also significantly lower in patient HCC than in peritumor or normal liver tissues. Our results reveal that ALDH2 functions as a tumor suppressor by maintaining genomic stability in the liver, and the common human ALDH2 variant would present a significant risk factor for hepatocarcinogenesis. Our study suggests that the ALDH2*2 allele–alcohol interaction may be an even greater human public health hazard than previously appreciated.Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is essential for alcohol detoxification. It is the second enzyme in the major oxidative pathway of alcohol metabolism, removing acetaldehyde (ACE), a toxic intermediate product from ethanol metabolism (1). More than 500 million people worldwide, mostly in East Asia, have a G-to-A point mutation in their ALDH2 gene (2, 3). This mutation results in a glutamic acid-to-lysine substitution at residue 487 (E487K) of the human ALDH2 protein (designated ALDH2*2). ALDH2*2 has significantly reduced ability to metabolize ACE (4, 5). Importantly, its activity is partially dominant-negative over that of the wild-type ALDH2*1, due to the structural alterations introduced by the mutation to the ALDH2 homotetramer complex (6). As a result, individuals with a heterozygous ALDH2*2/2*1 genotype have less than half the wild-type activity, and ALDH2*2/2*2 homozygotes have very low residual activity (7). Accumulated ACE can cause an alcohol flush reaction, commonly found in Asians with this variant after alcohol consumption (also called “Asian glow”).ACE binds to cellular proteins and DNA, leading to DNA damage and organ injury (8). Specifically, endogenous aldehydes are detrimental to hematopoietic stem cells that are defective in Fanconi anemia DNA repair (9, 10). As a result, Fanconi anemia patients with the ALDH2*2 allele exhibit accelerated disease progression (11). ALDH2*2 can also increase the risk for gastrointestinal cancers, such as gastric carcinoma (12), esophageal cancer (13), and colon cancer (14). Despite the liver being the major organ of ethanol detoxification, the relationship between ALDH2*2 and the risk for liver cancer remains unclear (15, 16).ALDH2 is highly conserved in humans and mice (17, 18), and several mouse models with modified ALDH2 activities have been developed (19). The closest model to the human ALDH2*2 polymorphism is the Aldh2 knockout (KO) mouse, which expresses no protein or enzymatic activity (20). Although Aldh2 KO mice are useful for investigating the impact of complete lack of ALDH2 activity (21), they fail to faithfully reproduce the structural and biochemical properties of ALDH2*2 in human physiology and pathology (2123). In particular, ALDH2*2 is expressed with reduced but not loss of enzymatic activity and increased protein turnover (24).To provide better mechanistic links between the ALDH2(E487K) mutation and human disease, we generated an ALDH2*2 knockin (KI) mouse. We observed impaired clearance of ACE from hepatocytes in these mutants after acute or chronic alcohol challenges. The ALDH2(E487K) mutation reduced total liver ALDH2 protein levels via a dominant-negative effect on protein stability, as has been documented for human tissues (24, 25). We also revealed a surprising role for ALDH2 as a liver tumor suppressor, raising the concern that this common human polymorphism may expose over 500 million carriers to greater risk of liver cancer.  相似文献   
900.

Background:

The aim of this study was to assess the efficacy of neoadjuvant anastrozole and fulvestrant treatment of large operable or locally advanced hormone-receptor-positive breast cancer not eligible for initial breast-conserving surgery, and to identify genomic changes occurring after treatment.

Methods:

One hundred and twenty post-menopausal patients were randomised to receive 1 mg anastrozole (61 patients) or 500 mg fulvestrant (59 patients) for 6 months. Genomic DNA copy number profiles were generated for a subgroup of 20 patients before and after treatment.

Results:

A total of 108 patients were evaluable for efficacy and 118 for toxicity. The objective response rate determined by clinical palpation was 58.9% (95% CI=45.0–71.9) in the anastrozole arm and 53.8% (95% CI=39.5–67.8) in the fulvestrant arm. The breast-conserving surgery rate was 58.9% (95% CI=45.0–71.9) in the anastrozole arm and 50.0% (95% CI=35.8–64.2) in the fulvestrant arm. Pathological responses >50% occurred in 24 patients (42.9%) in the anastrozole arm and 13 (25.0%) in the fulvestrant arm. The Ki-67 score fell after treatment but there was no significant difference between the reduction in the two arms (anastrozole 16.7% (95% CI=13.3–21.0) before, 3.2% (95% CI=1.9–5.5) after, n=43; fulvestrant 17.1% (95%CI=13.1–22.5) before, 3.2% (95% CI=1.8–5.7) after, n=38) or between the reduction in Ki-67 in clinical responders and non-responders. Genomic analysis appeared to show a reduction of clonal diversity following treatment with selection of some clones with simpler copy number profiles.

Conclusions:

Both anastrozole and fulvestrant were effective and well-tolerated, enabling breast-conserving surgery in over 50% of patients. Clonal changes consistent with clonal selection by the treatment were seen in a subgroup of patients.  相似文献   
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