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991.
The clinical, histopathological, and electron microscopic features of an unusual case of xanthogranulomatous appendicitis are reported. The patient, a 37-year-old female, presented with typical signs of acute appendicitis and the appendix appeared slightly dilated at laparatomy. The histopathological sections showed numerous xanthoma cells mixed with inspissated fecaliths. Electron microscopy disclosed the presence of xanthoma cells filled with electron-lucent lipid droplets of variable size. The ultrastructural characteristics of these cells enabled the distinction of two types of lipid-laden histiocytes, in relationship to the size of the lipid droplets. Since the lipid droplets were seen also in cells other than histiocytes, it appears that these changes are secondary to a common mechanism,comprising factors such as obstruction, hemorrhage, inflammation,and local hypoxia. 相似文献
992.
Vered Bieber Arnon D. Cohen Tamar Freud Nancy Agmon-Levin Smadar Gertel Howard Amital 《Immunologic research》2013,56(2-3):261-266
To assess the association between RA and chronic obstructive pulmonary disease (COPD) in a population-based case-control study. A cross-sectional analysis performed utilizing the database of Clalit Health Services, the largest healthcare provider organization in Israel. Patients over the age of 20 years who were diagnosed with RA (‘cases’) and who were treated with any anti-rheumatic drug were compared with a sample of age- and gender-matched enrollees (‘controls’) without regard for the prevalence of COPD. Data on health-related lifestyles and other comorbidities were collected. χ2, t tests, and logistic regression models were used to compare the study groups. The study included 9,039 RA cases and 15,070 controls. The proportion of COPD was significantly higher in patients with RA as compared to the control group (8.6 vs. 4.4 %, p < 0.0001, odds ratio (OR) 2.06, 95 % confidence interval (CI) 1.85–2.29). A multivariate logistic regression model demonstrated that RA was significantly associated with COPD, after controlling for confounders, including age, sex, socioeconomic status, smoking, and obesity (adjusted OR 1.98, 95 % CI 1.77–2.21, p < 0.0001). In this large data-based study, RA was found to be associated with COPD. 相似文献
993.
Michal Cohen‐Eliav Regina Golan‐Gerstl Zahava Siegfried Claus L Andersen Kasper Thorsen Torben F Ørntoft David Mu Rotem Karni 《The Journal of pathology》2013,229(4):630-639
An increasing body of evidence connects alterations in the process of alternative splicing with cancer development and progression. However, a direct role of splicing factors as drivers of cancer development is mostly unknown. We analysed the gene copy number of several splicing factors in colon and lung tumours, and found that the gene encoding for the splicing factor SRSF6 is amplified and over‐expressed in these cancers. Moreover, over‐expression of SRSF6 in immortal lung epithelial cells enhanced proliferation, protected them from chemotherapy‐induced cell death and converted them to be tumourigenic in mice. In contrast, knock‐down of SRSF6 in lung and colon cancer cell lines inhibited their tumourigenic abilities. SRSF6 up‐ or down‐regulation altered the splicing of several tumour suppressors and oncogenes to generate the oncogenic isoforms and reduce the tumour‐suppressive isoforms. Our data suggest that the splicing factor SRSF6 is an oncoprotein that regulates the proliferation and survival of lung and colon cancer cells. 相似文献
994.
995.
Johanna M. Jarcho Nathan A. Fox Daniel S. Pine Amit Etkin Ellen Leibenluft Tomer Shechner Monique Ernst 《Biological psychology》2013
The present study is the first to assess whether the neural correlates of cognitive control processes differ in adults with and without a behaviorally inhibited temperament during early childhood. Adults with and without childhood behavioral inhibition completed an emotional conflict task while undergoing functional magnetic resonance imaging scanning. While no group differences in behavior were observed, adults with childhood behavioral inhibition, relative to adults without childhood behavioral inhibition, exhibited greater dorsomedial prefrontal cortex activity during conflict detection and greater putamen activity during conflict adaptation. Lifetime psychopathology predicted behavioral, but not brain-related, differences in conflict adaptation. These data suggest that the brain regions underlying cognitive control processes are differentially influenced by childhood behavioral inhibition, and may be differently related to psychopathology. 相似文献
996.
One of the most promising areas in the therapeutics for metabolic diseases centers around activation of the pathways of energy expenditure. Brown adipose tissue is a particularly appealing target for increasing energy expenditure, given its amazing capacity to transform chemical energy into heat. In addition to classical brown adipose tissue, the last few years have seen great advances in our understanding of inducible thermogenic adipose tissue, also referred to as beige fat. A deeper understanding of the molecular processes involved in the development and function of these cell types may lead to new therapeutics for obesity, diabetes, and other metabolic diseases. 相似文献
997.
998.
Monique A. Pimontel Nili Solomonov Lauren Oberlin Theodora Kanellopoulos Jennifer N. Bress Matthew J. Hoptman George S. Alexopoulos Faith M. Gunning 《The American journal of geriatric psychiatry》2021,29(3):241-248
ObjectiveApathy is common in late-life depression and is associated with poor response to antidepressant drugs. In depressed older adults, apathy may be characterized by neuroanatomical abnormalities of the salience network. The current study examined whether cortical thickness of select salience network structures predicted change in apathy following a 12-week treatment with escitalopram.MethodsA sample of 46 older adults with major depressive disorder received 12 weeks of escitalopram treatment at a daily target dose of 20 mg. All participants underwent a structural brain MRI scan at baseline, and cortical thickness was estimated in key cortical nodes of the salience network: the caudal anterior cingulate cortex and the insula. We measured baseline and post-treatment symptoms using the Apathy Evaluation Scale and the Hamilton Depression Rating Scale.ResultsA thicker insula at baseline predicted reduction in apathy symptoms following 12 weeks of treatment with escitalopram, even when controlling for age, baseline depression severity and change in depressive symptoms.ConclusionReduced insular thickness predicted residual apathetic symptoms following escitalopram treatment. These results converge with our previous findings of abnormal functional connectivity of the insular cortex in older depressed individuals with apathy. Older depressed adults with apathy may benefit from alternative treatment approaches or augmentative interventions that target abnormalities of the salience network. 相似文献
999.
Caroline Mann Tim Schfer Anke Bletsch Maria Gudbrandsen Eileen Daly John Suckling Edward T. Bullmore Michael V. Lombardo MengChuan Lai Michael C. Craig MRC AIMS Consortium Simon BaronCohen Declan G.M. Murphy Christine Ecker 《Human brain mapping》2021,42(4):953
Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that is accompanied by neurodevelopmental differences in regional cortical volume (CV), and a potential layer‐specific pathology. Conventional measures of CV, however, do not indicate how volume is distributed across cortical layers. In a sample of 92 typically developing (TD) controls and 92 adult individuals with ASD (aged 18–52 years), we examined volumetric gradients by quantifying the degree to which CV is weighted from the pial to the white surface of the brain. Overall, the spatial distribution of Frustum Surface Ratio (FSR) followed the gyral and sulcal pattern of the cortex and approximated a bimodal Gaussian distribution caused by a linear mixture of vertices on gyri and sulci. Measures of FSR were highly correlated with vertex‐wise estimates of mean curvature, sulcal depth, and pial surface area, although none of these features explained more than 76% variability in FSR on their own. Moreover, in ASD, we observed a pattern of predominant increases in the degree of FSR relative to TD controls, with an atypical neurodevelopmental trajectory. Our findings suggest a more outward‐weighted gradient of CV in ASD, which may indicate a larger contribution of supragranular layers to regional differences in CV. 相似文献
1000.
Yihui Du Qiong Li Grigory Sidorenkov Marleen Vonder Jiali Cai Geertruida H. de Bock Yu Guan Yi Xia Xiuxiu Zhou Di Zhang Mieneke Rook Rozemarijn Vliegenthart Marjolein A. Heuvelmans Monique D. Dorrius P.M.A. van Ooijen Harry J.M. Groen Pim van der Harst Yi Xiao Shiyuan Liu 《Academic radiology》2021,28(1):36-45