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51.
CLASEY, JODY L, CLAUDE BOUCHARD, LAURIE WIDEMAN, JILL KANALEY, C DAVID TEATES, MICHAEL O THORNER, MARK L HARTMAN, ARTHUR WELTMAN. The influence of anatomical boundaries, age, and sex on the assessment of abdominal visceral fat. Single-slice abdominal computed tomography (CT) scanning has been used extensively for the measurement of abdominal visceral fat (AYF). Optimal anatomical scan location and pixel density ranges have been proposed and are specifically reported to allow for the replication and standardization of AVF measurements. Standardization of the anatomical boundaries for CT measurement of AVF and the influence of age and gender on results obtained with different boundary locations have received much less attention. To determine the influence of three boundary analysis methods (AVF-1, AVF-2, and AVF-3) on the measurement of AVF by CT, 54 older (60 years to 79 years) and 37 younger (20 years to 29 years) healthy men and women were examined. The measurement boundary for AVF-1 was the internal most aspect of the abdominal and oblique muscle walls, and the posterior aspect of the vertebral body. AVF-2 used fat measurements enclosed in a boundary formed by the midpoint of the abdominal and oblique muscle walls, and the most posterior aspect of the spinous process. AVF-3 used fat measurements enclosed in a boundary formed by the external border of the abdominal and oblique muscle walls, and the external border of the erector spinae. Greater AVF measures were obtained with AVF-2 and AVF-3 compared with AVF-1 (p<0.0001). These differences were greater in older compared with younger subjects (p<0.0001) and greater in women compared with men (p<0.02). The significantly greater AVF measurements obtained with AVF-2 and AVF-3 resulted from the inclusion of larger amounts of fat that are not drained by the portal circulation. This included retroperitoneal, intermuscular, and intramuscular lipid droplets, which increase with aging. On the basis of these results, we recommend the AVF-1 anatomical boundaries for the measurement of AVF in clinical investigations, particularly with older subjects. These data demonstrate the importance of precise and reproducible anatomical boundaries for the measurement of AVF, particularly in longitudinal studies.  相似文献   
52.
Cross-linked enzyme aggregates (CLEAs) are prepared by precipitation of an enzyme and then chemical cross-linking the precipitate. Three CLEAs of lipase with glutaraldehyde concentrations of 10 mM (CLEA A), 40 mM (CLEA B) and 60 mM (CLEA C) were prepared. Studies show that there is a trade-off between thermal stability vs transesterification/hydrolysis rate vs enantioselectivity. The initial rates for transesterification of β-citronellol for the uncross-linked enzyme and CLEAs A, B and C were 243, 167, 102 and 40 µmol mg?1 h?1, respectively. Their thermal stabilities in aqueous media, as reflected by their half-life values at 55°C, were 6, 9, 13 and 16 h, respectively. The enantioselectivity, E values (for kinetic resolution of β-citronellol by transesterification) were 19, 74, 11 and 6, respectively. These results show that CLEA C was the most thermostable; the uncross-linked enzyme was best at obtaining the highest transesterification rate; and CLEA A was best suited for the enantioselective synthesis. Scanning electron microscopy (SEM) showed that the morphology of CLEA was dependent upon the extent of cross-linking.  相似文献   
53.
目的:分析前列腺癌根治术后病理得分较穿刺得分增加的原因,并建立一个可以预测中国人群中前列腺癌根治术后病理升 级的模型。方法:以2008 年8 月至2013 年12 月在我院泌尿科行前列腺癌根治性切除术的264例患者的临床资料为基础,根据 术前和术后患者病理得分的变化将其分为升级组和未升级组。运用单因素和多因素logistic 回归分析病理升级的原因,并通过多 因素回归系数建立预测病理升级的诺模图。结果:264 例患者中,共238 例最终纳入统计分析,多因素logistic 回归分析显示前列 腺特异抗原密度(0R=3.854,P=0.001 )和穿刺Gleason(≤ 6)评分是中国人群中前列腺癌根治术后病理升级的独立危险因素。前列腺 特异抗原密度和穿刺得分的ROC 最佳截断取值为0.37 ng/ml 2和8 分。运用上述两个变量建立了一个可用于预测病理升级的诺 模图。结论:前列腺特异抗原密度和穿刺Gleason 评分是预测中国人群中前列腺癌根治术后病理升级的独立危险因素,本研究所 得的诺模图可以很好地预测前列腺癌根治术后的病理升级。  相似文献   
54.
Colorectal carcinoma (CRC) poses heavy burden to human health and has an increasing incidence. Currently, the existing biomarkers for CRC bring about restrained clinical benefits. GSK3β is reported to be a novel therapeutic target for this disease but with undefined molecular mechanisms. Thus, we aimed to investigate the regulatory effect of GSK3β on CRC progression via FTO/MZF1/c-Myc axis. Firstly, the expression patterns of GSK3β, FTO, MZF1 and c-Myc were determined after sample collection. Lowly expressed GSK3β but highly expressed FTO, MZF1 and c-Myc were found in CRC. After transfection of different overexpressed and interference plasmids, the underlying mechanisms concerning GSK3β in CRC cell functions were analysed. Additionally, the effect of GSK3β on FTO protein stability was assessed followed by detection of MZF1 m6A modification and MZF1-FTO interaction. Mechanistically, GSK3β mediated ubiquitination of demethylase FTO to reduce FTO expression. Besides, GSK3β inhibited MZF1 expression by mediating FTO-regulated m6A modification of MZF1 and then decreased the proto-oncogene c-Myc expression, thus hampering CRC cell proliferation. We also carried out in vivo experiment to verify the regulatory effect of GSK3β on CRC via FTO-mediated MZF1/c-Myc axis. It was found that GSK3β inhibited CRC growth in vivo which was reversed by overexpressing c-Myc. Taken together, our findings indicate that GSK3β suppresses the progression of CRC through FTO-regulated MZF1/c-Myc axis, shedding light onto a new possible pathway by which GSK3β regulates CRC.  相似文献   
55.
Annual cycles of growth and reproduction of hatchery–reared Florida largemouth bass, Micropterus salmoides floridanus , were investigated. Animals were raised on either forage (goldfish, Carassius auratus ) or a pelleted salmon feed. Male and female year–class 1 largemouth bass were sampled throughout one complete yearly cycle (January–December). A biphasic growth cycle was observed in both forage–fed and pellet–fed fish. No increase in body length or weight was observed until approximately midway through the spawning period (May), after which fish grew at a consistent rate for the remainder of the study. The reproductive cycle of forage–fed fish was characterized by a rapid increase in gonadosomatic index (GS1) between January and April, followed by a prolonged spawning period (April–July) during which GSI progressively declined. Fully regressed gonads were observed in September and October, and a resumption of gonadal recrudescence was observed between October and December. Visceral adipose deposits (expressed as mesenteric fat index; MFI) were resorbed during gonadal growth and the initial stages of the spawning period, and restored during the post–spawning phase. Fish raised on pelleted feed had growth and reproductive cycles that parallelled those of forage–fed fish, but several significant differences were observed between the two diet groups. During the growth phase of the cycle, pellet–fed largemouth bass grew significantly faster than forage–fed largemouth bass, and had significantly larger MFIs than forage–fed largemouth bass at all times of the year. Pellet–fed fish also had significantly larger GSIs than forage–fed fish. These data indicate that diet composition may be an important determinant of growth and reproductive function in this species.  相似文献   
56.
Sirtuin 5 (SIRT5) is a NAD+‐dependent class III protein deacetylase, and its role in prostate cancer has not yet been reported. Therefore, to explore the diagnosis and treatment of prostate cancer, we investigated the effect of SIRT5 on prostate cancer. Sirtuin 5 was assessed by immunohistochemistry in 57 normal and cancerous prostate tissues. We found that the tissue expression levels of SIRT5 in patients with Gleason scores ≥7 were significantly different from those in patients with Gleason scores <7 (P < .05, R > 0). Further, mass spectrometry and pathway screening experiments showed that SIRT5 regulated the activity of the mitogen‐activated protein kinase (MAPK) pathway, which in turn modulated the expression of MMP9 and cyclin D1. Being a substrate of SIRT5, acetyl‐CoA acetyltransferase 1 (ACAT1) was regulated by SIRT5. SIRT5 also regulated MAPK pathway activity through ACAT1. These results revealed that SIRT5 promoted the activity of the MAPK pathway through ACAT1, increasing the ability of prostate cancer cells to proliferate, migrate and invade. Overall, these results indicate that SIRT5 expression is closely associated with prostate cancer progression. Understanding the underlying mechanism may provide new targets and methods for the diagnosis and treatment of the disease.  相似文献   
57.
Although the diagnosis and therapy approach developed, techniques for the early diagnosis of HCC remain insufficient which results in poor prognosis of patients. The traditional biomarker AFP, however, has been proved with low specificity. Circulating exosomal ncRNAs revealed different profiles reflecting the characteristics of tumour. In this study, we mainly focused on circulating exosomal ncRNAs which might be the fingerprint for HCC, especially for the diagnosis or metastasis prediction. A high throughput lncRNA microarray in exosomes extracted from cell‐free plasma was applied. The risk score analysis was employed to screen the potential exosome‐derived lncRNAs in two independent sets based on different clinical parameters in 200 paired HCC patients. After a multi‐stage validation, we finally revealed three lncRNAs, ENSG00000248932.1, ENST00000440688.1 and ENST00000457302.2, increased in HCC comparing with the both chronic hepatitis (CH) patients and cancer‐free controls. ROC curve revealed a higher sensitivity and specificity in predicting the occurrence of HCC from cancer‐free controls and CH patients with the area under curve (AUC) of 0.905 and 0.879 by combining AFP. The three lncRNA panel combined with AFP also indicted a fingerprint function in predicting the metastasis of HCC with the AUC of 0.870. In conclusion, ENSG00000248932.1, ENST00000440688.1 and ENST00000457302.2 might be the potential biomarker for the tumorigenesis prediction from CH patients or healthy controls and may also be applied for dynamic monitoring the metastasis of HCC.  相似文献   
58.
目的:探讨心房颤动(房颤)患者射频消融术后复发的风险因素,并依此构建个性化的风险评分系统。方法:选取2017年1~8月行射频消融术的房颤患者154例作为研究对象,依据术后3个月的随访结果将患者分为复发组及未复发组,采用单因素分析和Logistic回归分析对各风险因素进行分析,构建其评分系统,采用Hosmer-Lemeshow拟合优度检验和ROC曲线下面积评价评分系统的准确度及区分度。结果:术后随访3个月的结果显示共37例(24.03%)房颤患者出现复发,房颤类型、病程、体质量指数(BMI)、左房前后径(LAD)、左房容积(LAV)及超敏C反应蛋白(hs-CRP)水平均是房颤复发的独立风险因素(P<0.05)。构建的风险评分系统得分为0~26分,Hosmer-Lemeshow拟合优度检验:x^2=7.520,P=0.482;ROC曲线下面积为0.864(95%CI:0.837~0.891),预测评分值为15分时,约登指数最大(0.605),此时的敏感度和特异度分别为77.3%和83.2%。结论:房颤患者射频消融术后的复发率较高,依据风险因素构建的风险评分系统具有较高的预测效率和区分能力,可作为房颤患者射频消融术后复发风险评估的参考工具。  相似文献   
59.
目的:研究持续镇痛分娩对产妇分娩结局和新生儿评分的影响。方法:选择2018年7月~2019年7月中国医科大学航空总医院(本院)采取硬膜外分娩镇痛的101例产妇,将其随机分为两组。当产生确切的镇痛效果,进入第二产程后,观察组的51例产妇采用0.4μg/m L舒芬太尼以及0.08%罗哌卡因进行持续镇痛分娩;对照组的50例产妇则在宫口开全后,使用生理盐水替代泵内的局麻药物,直到分娩结束。比较两组产妇催产素的使用率,宫口扩张度和第一、第二产程按压硬膜外自控镇痛泵的次数,分娩方式,新生儿的体质量,脐动脉血pH值,出生后1 min和5 min Apgar评分,产妇修复会阴部时的视觉模拟评分(visual analogue scale, VAS)评分及产妇对于第二产程镇痛的满意度评分。结果:两组产妇催产素的使用率、宫口扩张度和第一、第二产程按压硬膜外自控镇痛泵的次数、分娩方式(剖宫产率、器械助产率、自然分娩率)、第一产程镇痛时间、第一以及第二产程时间相比均无显著差异(P0.05);两组新生儿的体质量,脐动脉血pH值,出生后1 min和5 min Apgar评分小于8分的新生儿所占的比例相比没有明显的差异(P0.05);观察组产妇修复会阴部时的VAS评分明显低于对照组(P0.05),产妇对于第二产程镇痛的满意度评分明显高于对照组(P0.05)。结论:持续镇痛分娩对产妇分娩结局和新生儿评分无明显的影响,但可显著提高产妇对第二产程镇痛和修复会阴部时镇痛的满意度。  相似文献   
60.
摘要 目的:分析冠心病(CHD)患者血浆CD69、Wnt拮抗剂蛋白-1(DKK-1)与血脂、炎性因子的关系,并分析CD69和DKK1对于CHD患者的诊断价值。方法:选取2016年6月~2018年12月在我院诊治的CHD患者136例,根据Gensini评分分为轻度亚组、中度亚组、重度亚组,同时纳入与之年龄、性别匹配的冠状动脉造影正常者136例作为对照组。检测受试者血清炎性因子、血脂、及血浆CD69、DKK-1水平,分析CHD患者CD69、DKK-1水平与血脂、炎性因子、Gensini评分的相关性,采用受试者工作特征(ROC)曲线分析CD69和DKK1对于CHD患者的诊断价值。结果:CHD患者CD69、DKK-1、白细胞介素-10(IL-10)、白细胞介素-6(IL-6)、三酰甘油(TG)、总胆固醇(TC)、低密度脂蛋白(LDL)水平高于对照组,高密度脂蛋白(HDL)水平低于对照组(P<0.05);随着冠脉狭窄病变程度的加重,CD69、DKK-1、IL-10、IL-6、TC、TG、LDL水平呈升高趋势,HDL水平呈降低趋势(P<0.05)。CHD患者CD69、DKK-1水平与IL-10、IL-6、TC、TG、LDL、Gensini评分均呈正相关,与HDL呈负相关(P<0.05)。ROC曲线分析结果显示,CD69、DKK-1联合检测诊断CHD的灵敏度、特异度分别为0.816、0.846。结论:CHD患者血浆DKK-1、CD69水平升高,与血脂、炎性因子和Gensini评分密切相关,两者联合检测可提高CHD诊断效能。  相似文献   
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