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991.
Xuntao Yin Chen Liu Li Gui Lu Zhao Jiuquan Zhang Luqing Wei Bing Xie Daiquan Zhou Chuanming Li Jian Wang 《PloS one》2014,9(1)
Binswanger''s disease (BD) is a common cause of vascular dementia in elderly patients; however, few studies have investigated the medial temporal lobe (MTL) atrophy in BD, and the differences in the atrophic patterns between BD and Alzheimer''s disease (AD) remain largely unknown. Such knowledge is essential for understanding the pathologic basis of dementia. In this study, we collected structural magnetic resonance imaging (MRI) data from 16 normal controls, 14 patients with AD and 14 patients with BD. The volumes of the hippocampus and amygdala, and morphologic parameters (volume, surface area, cortical thickness and mean curvature) of the entorhinal cortex (ERC) and perirhinal cortex (PRC) were calculated using an automated approach. Volume reduction of the hippocampus, amygdala and ERC, and disturbance of the PRC curvature was found in both AD and BD patients compared with the controls (p<0.05, uncorrected). There were no significant differences among all the structural measures between the AD and BD patients. Finally, partial correlation analyses revealed that cognitive decline could be attributed to ERC thinning in AD and volume reduction of PRC in BD. We conclude that AD and BD exhibit similar atrophy patterns in the medial temporal cortices and deep gray matter but have distinct pathologic bases for cognitive impairments. Although atrophy of the MTL structures is a sensitive biomarker for AD, it is not superior for discrimination between AD and BD. 相似文献
992.
The structure of pseudorabies virus (PRV) capsids isolated from the nucleus of infected cells and from PRV virions was determined by cryo-electron microscopy (cryo-EM) and compared to herpes simplex virus type 1 (HSV-1) capsids. PRV capsid structures closely resemble those of HSV-1, including distribution of the capsid vertex specific component (CVSC) of HSV-1, which is a heterodimer of the pUL17 and pUL25 proteins. Occupancy of CVSC on all PRV capsids is near 100%, compared to ~ 50% reported for HSV-1 C-capsids and 25% or less that we measure for HSV-1 A- and B-capsids. A PRV mutant lacking pUL25 does not produce C-capsids and lacks visible CVSC density in the cryo-EM-based reconstruction. A reconstruction of PRV capsids in which green fluorescent protein was fused within the N-terminus of pUL25 confirmed previous studies with a similar HSV-1 capsid mutant localizing pUL25 to the CVSC density region that is distal to the penton. However, comparison of the CVSC density in a 9-Å-resolution PRV C-capsid map with the available crystal structure of HSV-1 pUL25 failed to find a satisfactory fit, suggesting either a different fold for PRV pUL25 or a capsid-bound conformation for pUL25 that does not match the X-ray model determined from protein crystallized in solution. The PRV capsid imaged within virions closely resembles C-capsids with the addition of weak but significant density shrouding the pentons that we attribute to tegument proteins. Our results demonstrate significant structure conservation between the PRV and HSV capsids. 相似文献
993.
Balarini MK de Paula TA da Matta SL Peixoto JV Guião-Leite FL Rossi Júnior JL Czermak Junior AC Walker NJ 《Theriogenology》2012,77(5):873-880
Six adult Leopardus tigrinus (oncilla) were studied to characterize stages of the seminiferous epithelium cycle and its relative frequency and duration, as well as morphometric parameters of the testes. Testicular fragments were obtained (incisional biopsy), embedded (glycol methacrylate), and histologic sections examined with light microscopy. The cycle of the seminiferous epithelium was categorized into eight stages (based on the tubular morphology method). The duration of one seminiferous epithelium cycle was 9.19 d, and approximately 41.37 d were required for development of sperm from spermatogonia. On average, diameter of the seminiferous tubules was 228.29 μm, epithelium height was 78.86 μm, and there were 16.99 m of testicular tubules per gram of testis. Body weight averaged 2.589 kg, of which 0.06 and 0.04% were attributed to the testis and seminiferous tubules, respectively. In conclusion, there were eight distinct stages in the seminiferous epithelium, the length of the seminiferous epithelium cycle was close to that in domestic cats and cougars, and testicular and somatic indexes were similar to those of other carnivores of similar size. 相似文献
994.
Jiali Zeng Jian Wang Jibin Wu Rui Deng Lun Zhang Qingru Chen Jie Wang Xiaobao Jin Shuiqing Gui Yinghua Xu Xuemei Lu 《Journal of cellular and molecular medicine》2023,27(3):340
Lysosomes, a central regulator of autophagy, play a critical role in tumour growth. Lysosomal protease cathepsin D can initiate apoptosis when released from lysosomes into the cytosol. In this study, we observed that Musca domestica cecropin (Mdc) 1–8 (M1‐8), a small anti‐tumour peptide derived from Mdc, inhibits hepatoma cell growth by blocking autophagy–lysosome fusion. This effect is likely achieved by targeting lysosomes to activate lysosomal protease D. Additionally, we examined whether lysosomal content and cathepsin D release were involved in M1‐8‐induced apoptosis. After exposure to M1‐8, human hepatoma HepG2 cells rapidly co‐localized with lysosomes, disrupted lysosomal integrity, caused leakage of lysosomal protease cathepsin D, caspase activation and mitochondrial membrane potential changes; and promoted cell apoptosis. Interestingly, in M1‐8‐treated HepG2 cells, autophagic protein content increased and the lysosome–autophagosome fusion was inhibited, suggesting that M1‐8 can cause apoptosis through autophagy and lysosomes. This result indicates that a small accumulation of autophagy and autolysosome inhibition in cells can cause cell death. Taken together, these data suggest a novel insight into the regulatory mechanisms of M1‐8 in autophagy and lysosomes, which may facilitate the development of M1‐8 as a potential cancer therapeutic agent. 相似文献
995.
Mei Li Xiaoying Fu Gui Ma Xiaodong Sun Xueyuan Dong Tamas Nagy Changsheng Xing Jie Li Jin-Tang Dong 《PloS one》2012,7(12)
ATBF1 is a candidate tumor suppressor that interacts with estrogen receptor (ER) to inhibit the function of estrogen-ER signaling in gene regulation and cell proliferation control in human breast cancer cells. We therefore tested whether Atbf1 and its interaction with ER modulate the development of pubertal mammary gland, where estrogen is the predominant steroid hormone. In an in vitro model of cell differentiation, i.e., MCF10A cells cultured in Matrigel, ATBF1 expression was significantly increased, and knockdown of ATBF1 inhibited acinus formation. During mouse mammary gland development, Atbf1 was expressed at varying levels at different stages, with higher levels during puberty, lower during pregnancy, and the highest during lactation. Knockout of Atbf1 at the onset of puberty enhanced ductal elongation and bifurcation and promoted cell proliferation in both ducts and terminal end buds of pubertal mammary glands. Enhanced cell proliferation primarily occurred in ER-positive cells and was accompanied by increased expression of ER target genes. Furthermore, inactivation of Atbf1 reduced the expression of basal cell markers (CK5, CK14 and CD44) but not luminal cell markers. These findings indicate that Atbf1 plays a role in the development of pubertal mammary gland likely by modulating the function of estrogen-ER signaling in luminal cells and by modulating gene expression in basal cells. 相似文献
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为探讨新生儿细胞色素P450 2E1(CYP2E1)基因多态性和对氧磷酶2(二乙基对硝基苯磷酸酯酶2)基因(PON2)148位点多态性对早产的影响,采用横断面调查方法,使用统一的调查表,由安庆市各县医院对入院分娩孕妇及其单胎、活产、早产和对照新生儿进行调查,共得到有效样本209个母亲-新生儿对。单因素分析结果显示:CYP2E1野生纯合子基因型( / )与突变纯合子基因型(-/-)/杂合子基因型( /-)比较,对早产的影响不具有统计学意义。而PON2 Alal48Ala纯合子基因型与G1y148G1y纯合子基因型/Ala148 Gly杂合子基因型比较,对早产的影响具有显著的统计学意义。进一步分析CYP2E1基因5′端RsaⅠ位点多态性和PON2基因148位点多态性是否存在交互作用,结果显示:CYP2E1野生纯合子基因型和PON2 Ala148Ala纯合子基因型这一组合与参照组比较,对早产的影响有显著的统计学意义。基因CYP2E1 5′端Rsa I位点多态性与新生儿早产不相关,但基因PON2 148位点多态性与新生儿早产相关,且CPY2E1 5′端Rsa I位点多态性和PON2 148位点多态性之间对早产的影响存在交互作用。 相似文献