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991.
Ester Cerin Stephanie R. Rainey-Smith David Ames Nicola T. Lautenschlager S. Lance Macaulay Christopher Fowler Joanne S. Robertson Christopher C. Rowe Paul Maruff Ralph N. Martins Colin L. Masters Kathryn A. Ellis 《Alzheimer's & dementia》2017,13(4):388-398
Introduction
“Walkable” neighborhoods offer older adults opportunities for activities that may benefit cognition-related biological mechanisms. These have not previously been examined in this context.Methods
We objectively assessed neighborhood walkability for participants (n = 146) from the Australian Imaging, Biomarkers and Lifestyle study with apolipoprotein E (APOE) genotype and two 18-month-apart brain volumetric and/or amyloid β burden assessments. Linear mixed models estimated associations of neighborhood walkability with levels and changes in brain imaging outcomes, the moderating effect of APOE ε4 status, and the extent to which associations were explained by physical activity.Results
Cross-sectionally, neighborhood walkability was predictive of better neuroimaging outcomes except for left hippocampal volume. These associations were to a small extent explained by physical activity. APOE ε4 carriers showed slower worsening of outcomes if living in walkable neighborhoods.Discussion
These findings indicate associations between neighborhood walkability and brain imaging measures (especially in APOE ε4 carriers) minimally attributable to physical activity. 相似文献992.
Annick Bosch Joanne Riebschleger Linda van Loon 《International Journal of Mental Health Promotion, The》2017,19(3):159-172
Children of parents with a mental illness (COPMI) have a higher risk of acquiring a mental illness themselves. Feelings of guilt and shame could increase COPMI risks of acquiring mental health disorder symptoms. These feelings of guilt and shame could also impact the quality of the parent-child relationship. Data were drawn from the qualitative part of a mixed method study featuring 18 face-to-face interviews with Dutch COPMI aged 12–21. Interviewees were asked about their experiences with guilt and shame related to their parent with mental illness and the extent they felt that these feelings affected their relationships with their parents. Qualitative thematic analysis (QTA) revealed that most COPMI youth described feelings of guilt and some of them reported feelings of shame. They reported making behavioral adjustments especially using caution in parental communication. In their perception, guilt and shame did not have long-term impacts on their relationships with parents. 相似文献
993.
Genetic effect of MTHFR C677T polymorphism on the structural covariance network and white‐matter integrity in Alzheimer's disease 下载免费PDF全文
Shih‐Wei Hsu Ya‐Ting Chang Chi‐Wei Huang Mu‐En Liu Nai‐Ching Chen Wen‐Neng Chang Jung‐Lung Hsu Chen‐Chang Lee Chiung‐Chih Chang 《Human brain mapping》2017,38(6):3039-3051
The 677 C to T transition in the MTHFR gene is a genetic determinant for hyperhomocysteinemia. We investigated whether this polymorphism modulates gray matter (GM) structural covariance networks independently of white‐matter integrity in patients with Alzheimer's disease (AD). GM structural covariance networks were constructed by 3D T1‐magnetic resonance imaging and seed‐based analysis. The patients were divided into two genotype groups: C homozygotes (n = 73) and T carriers (n = 62). Using diffusion tensor imaging and white‐matter parcellation, 11 fiber bundle integrities were compared between the two genotype groups. Cognitive test scores were the major outcome factors. The T carriers had higher homocysteine levels, lower posterior cingulate cortex GM volume, and more clusters in the dorsal medial lobe subsystem showing stronger covariance strength. Both posterior cingulate cortex seed and interconnected peak cluster volumes predicted cognitive test scores, especially in the T carriers. There were no between‐group differences in fiber tract diffusion parameters. The MTHFR 677T polymorphism modulates posterior cingulate cortex‐anchored structural covariance strength independently of white matter integrities. Hum Brain Mapp 38:3039–3051, 2017. © 2017 The Authors Human Brain Mapping Published Wiley by Periodicals, Inc. 相似文献
994.
Liu Y Khadka A Li J Hu J Zhu S Hsu Y Wang Q Wang D 《International journal of oral and maxillofacial surgery》2011,40(11):1238-1245
The traditional approach for ankylosis is gap arthroplasty or interpositional arthroplasty followed by reconstruction of the condyle using, for example, costochondral grafts. As these are non-pedicled grafts, there is eventual resorption with subsequent decrease in height of the ramus, facial asymmetry and deviated mouth opening. The authors have applied the method of total and partial sliding vertical osteotomy on the posterior border of the mandibular ramus for reconstruction of the mandible condyle as a pedicled graft for the correction of temporomandibular joint (TMJ) ankylosis. From 2004 to 2008, 18 patients who were diagnosed with TMJ ankylosis underwent operations for resection of the ankylosed condyle. Two methods were performed depending on the level of osteotomy on the posterior part of the mandibular ramus. All patients were followed-up for an average of 36 months (range 24-48 months). All patients showed apparent improved joint function with no cases of re-ankylosis. The results showed that sliding vertical osteotomy on the posterior border of the mandibular ramus seems to be an alternative and promising method for condylar reconstruction in patients with TMJ bony ankylosis. 相似文献
995.
R H Mehta F Helmcke N C Nanda M Hsiung A D Pacifico T L Hsu 《Journal of the American College of Cardiology》1990,16(4):1010-1016
Transesophageal Doppler color flow imaging was performed in 19 adult patients (mean age 35 years) with an atrial septal defect demonstrated by cardiac catheterization or at surgery, or both. The transesophageal study correctly identified and classified 19 of 19 shunts in contrast to 16 of 18 shunts identified by the transthoracic approach. The area of the atrial septal defect was calculated by assuming it to be circular and taking the maximal Doppler color flow jet width at the defect site as its diameter. The pulsed Doppler sample volume was placed parallel to the shunt flow direction at the defect site to obtain the mean velocity and flow duration. From these values, the shunt volume was calculated as a product of the defect area, mean velocity, flow duration and heart rate. The calculated shunt flow volume obtained by transesophageal study showed a good correlation with shunt flow volume (r = 0.91, p less than 0.001) and pulmonary to systemic blood flow ratio (r = 0.84, p less than 0.001) obtained at cardiac catheterization. The size of the defect by transesophageal Doppler color flow mapping correlated fairly well with the size estimated at surgery (r = 0.73, p = 0.004). It is concluded that transesophageal Doppler color flow imaging is useful in the detection and classification of atrial septal defects and in the assessment of shunt volumes. 相似文献
996.
Fibroblast-mediated acceleration of human epithelial tumor growth in vivo. 总被引:21,自引:2,他引:21 下载免费PDF全文
J L Camps S M Chang T C Hsu M R Freeman S J Hong H E Zhau A C von Eschenbach L W Chung 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(1):75-79
Transformed fibroblasts coinoculated with epithelial cells accelerated the growth and shortened the latency period of human epithelial tumors in athymic mice. Addition of NbF-1 fibroblasts caused epithelial tumors to grow from five marginally tumorigenic or "nontumorigenic" (nontumor-forming) human tumor cell lines or strains: PC-3 (prostate), WH (bladder), MDA-436 (breast), and cells derived from the ascites fluids of patients with metastatic renal pelvic or prostate cancers. Evidence for the human and epithelial nature of these experimental tumors was provided by histologic, immunohistochemical, Southern and dot-blot hybridization, and cytogenetic analyses. Transformed fibroblasts induced predominantly carcinosarcomas, whereas nontumorigenic fibroblasts (NIH 3T3) and lethally irradiated transformed fibroblasts induced exclusively carcinomas. The fibroblast-epithelial interaction appears to occur bidirectionally and does not result from cell fusion. Because coculture experiments in vitro did not demonstrate an increased cell proliferation, it appears that undefined host factors can influence tumor growth. This tumor model may be useful in drug-screening programs and in mechanistic studies of factors regulating human tumor growth and progression. 相似文献
997.
D W Hsu M el-Azouzi P M Black W W Chin E T Hedley-Whyte L M Kaplan 《Endocrinology》1990,126(6):3159-3167
Galanin is a widely distributed regulatory peptide which modulates the pituitary secretion of PRL and GH. Estrogen administration strongly stimulates galanin gene expression in the rat anterior pituitary. In adult female Fischer 344 rats, estrogen also induces hyperplasia of lactotropes. We used immunocytochemical analysis to assess the effects of estrogen on galanin-like immunoreactivity (Gal-IR) in the rat pituitary and hypothalamus during sc diethylstilbestrol (DES) implantation and after its removal at 30 days. In the anterior pituitary, DES implantation increased the portion of Gal-IR-containing cells from less than 2% in the control rats to 18.3% after 3 days of DES and 36% after 30 days. These changes paralleled the lactotrope hyperplasia exhibited in response to DES exposure. Ten and 30 days after removal of the DES capsules, the percentage of Gal-IR-containing cells in the anterior pituitary decreased to 6.3% and 1.5%, respectively. Colocalization studies revealed that Gal-IR-containing cells were predominantly lactotropes. Immunoelectron microscopy demonstrated that Gal-IR was concentrated in the Golgi region of these hyperplastic lactotropes and suggests that little of the synthesized galanin is secreted. The distribution of Gal-IR in the hypothalamus, median eminence, and neurohypophysis was unaffected by DES treatment. These data demonstrate that galanin is synthesized by hyperplastic pituitary lactotropes of Fischer 344 rats and that peptide accumulation is dependent on the presence of circulating estrogens. In contrast, neuronal galanin synthesis in the hypothalamus does not appear to be regulated by estrogen. 相似文献
998.
Matrix vesicle biogenesis in vitro by rachitic and normal rat chondrocytes. 总被引:3,自引:0,他引:3 下载免费PDF全文
H. C. Anderson D. J. Stechschulte Jr D. E. Collins D. H. Jacobs D. C. Morris H. H. Hsu P. A. Redford S. Zeiger 《The American journal of pathology》1990,136(2):391-398
Calcifying matrix vesicles (MVs) are released from chondrocytes and osteoblasts in monolayer culture. In the present studies, we tested the ability of rachitic versus normal rat growth plate chondrocytes in micromass or monolayer primary cultures to produce MVs. Unlike earlier reports of in vitro MV biogenesis by chicken chondrocytes in which most MVs were released into the medium, we found that most of the released rat matrix vesicles were entrapped in a newly formed cartilaginous matrix enveloping the cells. These matrix-associated MVs could be isolated by mild collagenase treatment and concentrated by differential centrifugation. Vesicle production slowed in the older 2- to 4-week-old cultures and, unlike vesicle release from cultured chicken chondrocytes, active vesicle production did not show a second burst of activity at 3 to 4 weeks. Alkaline phosphatase (ALP) activity diminished with time in culture in cells and matrix vesicles, suggesting a decrease in differentiative expression. Protein profiles on SDS polyacrylamide gels of native matrix vesicles and culture-derived MVs from rachitic and normal cells were quite similar and showed a typical simplified protein pattern as compared to chondrocyte plasma membrane proteins. There were distinctive proteins migrating at 130, 80 to 95, 66, 43, 20, and 14 kd. Culture-derived MVs showed vigorous in vitro calcifying activity that was ALP related. We conclude that 1) rachitic chondrocytes are essentially normal in their matrix vesicle production; 2) matrix entrapment of MVs is a characteristic of rat chondrocyte cultures; and 3) culture-produced MVs are similar to native MVs in protein profile and calcifiability, and thus can be studied as a model for normal MV composition and calcification. 相似文献
999.
Cultured Reed-Sternberg cells HDLM-1 and KM-H2 can be induced to become histiocytelike cells. H-RS cells are not derived from lymphocytes. 下载免费PDF全文
Two Hodgkin's Reed-Sternberg cell (H-RS) lines, HDLM-1 and KM-H2, have phenotypes and functional properties very similar to those of H-RS cells in tissues. These two types of cells were induced to differentiate with a combination of phorbol ester, retinoic acid, and extracellular matrix. The induced cells displayed the morphology of histiocytes or histiocytelike cells, with a small, round or oval, eccentric nucleus and abundant cytoplasm. In ultrastructural studies, many cytoplasmic projections and rugae were observed. These induced cells exhibited abundant cytoplasmic lysosomal enzymes, such as esterase, acid phosphatase, alpha 1-antitrypsin, or lysozyme. The histiocytic nature of these induced cells was further confirmed by the increased expression of many monocyte/histiocyte markers, including CD11b, CD11c, CD13, CD14, CD15, CD33, CD68, Mac387, and 1E9. In functional tests, the induced cells were shown to produce interleukin-1, tumor necrosis factor, macrophage colony-stimulating factor, and/or prostaglandin E2. Phagocytosis was detected in less than 5% to 10% of the cells when Candida albicans was added to cultures. The results strongly suggest that H-RS cells are related to cells of histiocyte lineage. 相似文献
1000.
Mu-Hong Chen Tung-Ping Su Ying-Sheue Chen Ju-Wei Hsu Kai-Lin Huang Wen-Han Chang Tzeng-Ji Chen Tai-Long Pan Ya-Mei Bai 《Journal of psychosomatic research》2014