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991.
Massimo Filippi Gianna Riccitelli Alessandro Meani Andrea Falini Giancarlo Comi Maria A. Rocca 《Brain structure & function》2013,218(5):1211-1227
An array of brain regions in the fronto-parietal and temporal lobes cooperates to process observation and execution of actions performed by other individuals. Using functional MRI, we hypothesized that vegetarians and vegans might show brain responses to mouth actions performed by humans, monkeys, and pigs different from omnivores. We scanned 20 omnivores, 19 vegetarians, and 21 vegans while watching a series of silent videos, which presented a single mouth action performed by a human, a monkey, and a pig. Compared to omnivores, vegetarians and vegans have increased functional connectivity between regions of the fronto-parietal and temporal lobes versus the cerebellum during observation of mouth actions performed by humans and, to the same degree, animals. Vegans also had increased connectivity with the supplementary motor area. During human mouth actions, increased amygdala activity in vegetarians and vegans was found. More critically, vegetarians recruited the right middle frontal gyrus and insula, which are involved in social mirroring, whereas vegans activated the left inferior frontal gyrus and middle temporal gyrus, which are part of the mirror neuron system. Monkey mouth actions triggered language network activity in both groups, which might be due to the attempt to decode monkey mouth gesture, with an additional recruitment of associative temporo-occipital areas in vegans, whereas pig mouth actions activated empathy-related regions, including the anterior cingulum. These results support the role of the action observation–execution matching system in social cognition, which enables us to interact not only with our conspecifics but also with species in phylogenetic proximity to humans. 相似文献
992.
Zheng‐Lai Ma Li‐Jing Wang Manli Chuai Andrea Münsterberg Jian‐Guo Geng Xuesong Yang 《Anatomical record (Hoboken, N.J. : 2007)》2013,296(3):533-543
Primitive streak (PS) is the first structure occurring in embryonic gastrulation, in which the epiblast cells undergo the epithelial‐mesenchymal transition to become the loose mesoderm cells subsequently. Because the mesoderm cells departing from different portions of PS are blessed with disparate migration trajectory and differentiation fate, one question is when the cell fate is determinated. To understand whether the cell fate and cell migration pattern will be alternated along with the microenvironment transformation, the traditional transplantation technology was used to replace the anterior PS cells in HH4 host embryo using posterior PS tissue labeled by green fluorescent protein (GFP) in the same stage donor embryo, and then, we tracked the migration trajectory of the GFP‐positive cells with fluorescence stereomicroscope after incubation, and eventually verified the cell contribution from the transplants with in situ hybridization and immunocytochemistry. The same experimental strategy applied for posterior PS site replacement in host embryo. We found that the transplanted posterior PS cells to anterior part of streak followed the anterior PS cell migration pattern rather than kept its posterior streak cell migration trajectory, and so did vice versa. In addition, the transplants were involved in the contribution to the subsequent organogenesis as the local PS tissues affirmed by specific expression of myocardial or hematopoietic markers. Therefore, our data strongly suggest that the PS cells still keep stem cell plasticity during gastrulation and the eventual cell fate will depend on the spatial gene expression within local microenvironment along with development. Anat Rec, 296:533–543, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
993.
994.
Livia Garavelli Graziella Simonte Simonetta Rosato Anita Wischmeijer Enrico Albertini Elisa Guareschi Caterina Longo Giuseppe Albertini Chiara Gelmini Chiara Greco Stefania Errico Gustavo Savino Marco Pavanello Rudolf Happle Sheila Unger Andrea Superti‐Furga Karl‐Heinz Grzeschik 《American journal of medical genetics. Part A》2013,161(7):1750-1754
995.
Carole A. Samango‐Sprouse Teresa Sadeghin Francine L Mitchell Teresa Dixon Emily Stapleton Madison Kingery Andrea L. Gropman 《American journal of medical genetics. Part A》2013,161(3):501-508
The effects of early androgen treatment on neurodevelopmental performance in pre‐pubertal boys with 47,XXY have not been well investigated. The influence of hormones on brain development in humans suggests that a positive effect on neurodevelopmental outcome in young boys with XXY may be plausible with hormone replacement therapy. The aim of the study was to investigate retrospectively if an early course of androgen treatment (three injections of testosterone enanthate, 25 mg, each) had an impact on specific domains of neurodevelopmental function in boys with 47,XXY at 36 and 72 months of age. One hundred one boys with a karyotype of 47,XXY had neurodevelopmental assessments. The retrospective chart review resulted in one group (n = 34) who had received androgen treatment during infancy and the second group was untreated (N = 67). Statistical analysis was completed to determine if there was a positive effect from treatment observed at 36 and at 72 months on multiple domains of development. There were significant differences in multiple cognitive domains in the group who received androgen treatment, including multiple measures of language, intellectual, and neuromotor skills. Improved function was observed in neurodevelopmental outcome in boys with 47,XXY at 36 and 72 months who had been treated with a short course of androgen treatment in infancy. Continued research is underway to expand our understanding of the relationship of androgen, brain function, and neurobehavioral and neurodevelopmental outcome in boys with 47,XXY. © 2013 Wiley Periodicals, Inc. 相似文献
996.
A decline in the mitochondrial functions and aging are two closely related processes. The presence of estrogen and androgen receptors and hormone-responsive elements in the mitochondria represents the starting point for the investigation of the effects of 17β-estradiol and testosterone on the mitochondrial functions and their relationships with aging. Both steroids trigger a complex molecular mechanism that involves crosstalk between the mitochondria, nucleus, and plasma membrane, and the cytoskeleton plays a key role in these interactions. The result of this signaling is mitochondrial protection. Therefore, the molecular components of the pathways activated by the sexual steroids could represent targets for anti-aging therapies. In this review, we discuss previous studies that describe the estrogen- and testosterone-dependent actions on the mitochondrial processes implicated in aging. 相似文献
997.
Andrea B. Conway M.D. Melissa K. Hart M.D. Jose Jessurun M.D. Stefan E. Pambuccian M.D. 《Diagnostic cytopathology》2013,41(3):247-252
Large three‐dimensional cell aggregates and psammoma bodies are usually encountered in benign serous effusions (mesothelial hyperplasia and endosalpingiosis), mesotheliomas, and metastatic papillary carcinomas. We report a case of pulmonary small‐cell carcinoma occurring in an 88‐year‐old woman that initially presented with a malignant pleural effusion characterized cytologically by a predominance of large three‐dimensional neoplastic cell aggregates (“cannonballs”), associated with rare psammoma bodies. Although the crowded three‐dimensional tumor‐cell aggregates did not allow detailed cytologic examination, the diagnosis of metastatic small‐cell carcinoma could be established noting the characteristic chromatin features of the occasional single neoplastic cells and the characteristic “cell‐in‐cell” and “stack‐of‐coins” arrangements of rare small clusters of neoplastic cells. Immunoperoxidase stains showing positivity of the tumor cells for CD56, synaptophysin, and TTF1 further supported this diagnosis. Endobronchial ultrasound‐guided fine‐needle aspiration of a mediastinal lymph node subsequently confirmed the diagnosis of pulmonary small‐cell carcinoma. Metastatic pulmonary small‐cell carcinoma should be considered in the differential diagnosis of serous effusions showing large three‐dimensional neoplastic cell aggregates and psammoma bodies to prevent a potential diagnostic pitfall. Diagn. Cytopathol. 2013. © 2011 Wiley Periodicals, Inc. 相似文献
998.
Andrea B. Conway M.D. Shelly M. Cook M.D. Arbaz Samad M.D. Rajeev Attam M.D. Stefan E. Pambuccian M.D. 《Diagnostic cytopathology》2013,41(8):661-672
Intrapancreatic and intraabdominal accessory spleens (IPIASs) are rarely encountered in endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) biopsies. However, as incidentally discovered IPIAS can mimic a benign or malignant pancreatic neoplasm on imaging studies, a definitive diagnosis made by EUS‐FNA can avert an unnecessary surgical intervention or additional radiologic follow‐up. We report five cases of intrapancreatic splenules and one case of accessory spleen (AS) in which a definitive diagnosis was made on EUS‐FNA. Previously recognized FNA cytomorphologic features of splenic tissue, including ASs and splenosis, are endothelial cells and polymorphous lymphocytes admixed with neutrophils, eosinophils, plasma cells, histiocytes, and lymphoglandular bodies. We describe the additional finding of abundant large platelet aggregates as another distinguishing feature of splenic tissue on FNA. In all six cases, large platelet aggregates were identified along with polymorphous lymphoid cells, lymphoglandular bodies, loose aggregates of endothelial cells and scattered or aggregated bland spindle cells. A review of 10 consecutive cases of EUS‐FNA‐sampled benign intraabdominal lymph nodes showed that the presence of large platelet aggregates, three‐dimensional aggregates of lymphoid cells and of bland slender spindle cells and the absence of follicular germinal cell components (tingible body macrophages and lymphohistiocytic aggregates) are useful in differentiating IPIASs from reactive lymph nodes. Immunoperoxidase stains were useful to confirm a suspected IPIASs by showing CD31‐positive acellular flocculent material, consistent with large platelet aggregates and a rich CD8‐positive endothelial cell network between CD45‐positive lymphoid cells and CD68‐positive histiocytes in all six cases. Diagn. Cytopathol. 2013;41:661–672. © 2013 Wiley Periodicals, Inc. 相似文献
999.
Christof Holberg Philipp Winterhalder Andrea Wichelhaus Reinhard Hickel Karin Huth 《Dental materials》2013
Objectives
In the present study, lithium-disilicate ceramic inlays should be analyzed biomechanically according to their thickness and dimension, and it should be clarified as to whether there is a significant relationship between the inlay volume and the induced tensile stress level.Methods
Using a new parametric CAD modeling procedure, 27 lithium-disilicate ceramic inlays with various parameters of “depth”, “width”, “angle” and restoration volume were generated. These inlays were integrated into the CAD model of a lower molar created from the CT data of an anatomical preparation. The resulting CAD models were, finally, three-dimensionally cross-linked to FEM models. After applying a compressive force of 200 N, Principal Tensile Stresses (PTSs) could be measured in the inlay. The values were subject to statistical analysis afterwards.Results
The volume of the inlay restorations varied between 35.7 mm3 and 82.5 mm3. The maximum PTS values (n = 10) only showed a slight negative correlation with the inlay volume. The correlation coefficient according to Spearman was −0.082 (p ≤ 0.001). If the highest 1000 PTS values of each inlay were considered (n = 1000), the correlation coefficient was further reduced to +0.068 (p ≤ 0.001). No significant correlation between the inlay volume and the induced PTS level could be detected.Significance
Under the conditions and limitations of the present FEM study, the inlay volume did not significantly influence the tensile stress level of ceramic inlays. The results may support the thesis that volume-reduced all-ceramic inlays might not have an increased fracture risk. Further studies are needed to confirm this. 相似文献1000.
Greg J. Knepil Caroline T. Harvey Andrea N. Beech 《The British journal of oral & maxillofacial surgery》2013,51(5):413-415
We present a system for marking the skin during oral surgical operations. This system identifies teeth to be extracted or exposed under general anaesthesia. Removal of the wrong tooth can cause appreciable morbidity and leaves the surgeon and organisation liable for litigation and scrutiny by regulatory bodies. A recent review of claims to the NHS litigation authority between 1995 and 2010 showed that in the field of oral and maxillofacial surgery, dentoalveolar surgery resulted in the largest number of claims for negligence, of which removal of the wrong tooth was one of the most common. In 2010/2011 the National Reporting and Learning System (NRLS) of the National Patient Safety Agency (NPSA) were notified of 20 incidents when the wrong tooth had been extracted, which accounted for 5% of all incidents reported. We have therefore developed a robust marking system for oral surgical procedures in our hospital, which improves on the World Health Organisation (WHO) checklist. We have audited patients’ perceptions and the clinical application of our marking system, and have shown that the system is welcomed by patients, and is simple and effective for clinicians to use. 相似文献