有限元数字化膝关节模型构建的研究与应用

背景：膝关节的解剖结构和力学特征决定它的生物力学特性,应用有限元分析方法对膝关节生物力学机制及损伤机制进行研究,可以有效地指导预防和治疗膝关节疾患。 目的：评价有限元数字化膝关节模型构建的研究和应用价值。 方法：以“CT,MRI,膝关节,有限元,模型构建”为关键词,采用计算机检索2005年1月至2011年11月维普数据库和万方数据库相关文章。纳入与膝关节模型构建及应用相关的文章;排除重复研究或Meta分析类文章。以9篇文献为重点讨论CT、MRI和有限元模型构建在膝关节中的研究和应用。 结果与结论：CT、MRI所采集到的DICM图像在有限元模型构建中各具优缺点,有限元模型合理应用,能够为膝关节的手术提供更全面、更可靠的影像学资料,临床医师可根据模型进行手术方案设计,模拟手术流程,显著降低了手术风险,减少了患者的痛苦。     

Lack of association between the CALM1 core promoter polymorphism (-16C/T) and susceptibility to knee osteoarthritis in a Chinese Han population

Background

Familial adenomatous polyposis (FAP) is typically characterized by multiple colonic polyps and frequent extracolonic features. Whereas the number of colonic polyps has been linked to the APC gene mutation, possible genotype-phenotype correlations largely remain to be defined for the extracolonic manifestations.

Methods

Full genomic sequencing combined with multiplex ligation-dependent probe amplification was used to identify APC gene mutations, which were correlated to the clinical presentations.

Results

10 novel APC gene mutations were identified in 11 families. A broad spectrum of extracolonic manifestations was identified in most of these individuals. Two sisters with an insertion in codon 528 (c.1582_1583insGC) both showed severe phenotypes with classical polyposis, upper gastrointestinal polyps and thyroid cancer. A woman with a 3'APC mutation (c.5030_5031insAA) developed colon cancer at age 72 as the first manifestation of attenuated FAP.

Conclusion

With an increasing number of FAP families diagnosed, a broad and variable tumor spectrum and a high frequency of extracolonic manifestations are gradually recognized. We report novel APC mutations and present two FAP cases that suggest familial aggregation of thyroid cancer and demonstrate the need to consider attenuated FAP also among elderly patients with colon cancer.     

Collagen I gel can facilitate homogenous bone formation of adipose-derived stem cells in PLGA-beta-TCP scaffold

Cell-based tissue engineering is thought to be a new therapy for treatment of bone defects and nonunions after trauma and tumor resection. In this study, we explore the in vitro and in vivo osteogenesis of a novel biomimetic construct fabricated by using collagen I gel to suspend rabbit adipose-derived stem cells (rASCs) into a porous poly(lactic-co-glycolic)acid-beta-tricalcium phosphate (PLGA-beta-TCP) scaffold (rASCs-COL/PLGA-beta-TCP). In vitro and in vivo studies of the rASCs-COL/PLGA-beta-TCP composite (group A) were carried out compared with the single combination of rASCs and PLGA-beta-TCP (rASCs/PLGA-beta-TCP; group B), the combination of acellular collagen I gel and PLGA-beta-TCP (COL/PLGA-beta-TCP; group C), and the PLGA-beta-TCP scaffold (group D). Composites of different groups were cultured in vitro for 2 weeks in osteogenic medium and then implanted into the autologous muscular intervals for 8 weeks. After 2 weeks of in vitro culture, alkaline phosphatase activity and extracellular matrix mineralization in group A were significantly higher than in group B (p < 0.01, n = 4). In vivo osteogenesis was evaluated by radiographic and histological analyses. The calcification level was radiographically evident in group A, whereas no apparent calcification was observed in groups B, C and D (n = 4). In group A, woven bone with a trabecular structure was formed, while in group B, only osteoid tissue was observed. Meanwhile, the bone-forming area in group A was significantly higher than in group B (p < 0.01, n = 4). No bone formation was observed in groups C or D (n = 4). In conclusion, by using collagen I gel to suspend rASCs into porous PLGA-beta-TCP scaffold, osteogenic differentiation of rASCs can be improved and homogeneous bone tissue can be successfully formed in vivo.     

Genome-wide association study identifies breast cancer risk variant at 10q21.2: results from the Asia Breast Cancer Consortium

Although approximately 20 common genetic susceptibility loci have been identified for breast cancer risk through genome-wide association studies (GWASs), genetic risk variants reported to date explain only a small fraction of heritability for this common cancer. We conducted a four-stage GWAS including 17 153 cases and 16 943 controls among East-Asian women to search for new genetic risk factors for breast cancer. After analyzing 684 457 SNPs in 2062 cases and 2066 controls (Stage I), we selected for replication among 5969 Chinese women (4146 cases and 1823 controls) the top 49 SNPs that had neither been reported previously nor were in strong linkage disequilibrium with reported SNPs (Stage II). Three SNPs were further evaluated in up to 13 152 Chinese and Japanese women (6436 cases and 6716 controls) (Stage III). Finally, two SNPs were evaluated in 10 847 Korean women (4509 cases and 6338 controls) (Stage IV). SNP rs10822013 on chromosome 10q21.2, located in the zinc finger protein 365 (ZNF365) gene, showed a consistent association with breast cancer risk in all four stages with a combined per-risk allele odds ratio of 1.10 (95% CI: 1.07-1.14) (P-value for trend = 5.87 × 10(-9)). In vitro electrophoretic mobility shift assays demonstrated the potential functional significance of rs10822013. Our results strongly implicate rs10822013 at 10q21.2 as a genetic risk variant for breast cancer among East-Asian women.     

Personal food systems of male collegiate football players: a grounded theory investigation

Context:

Factors that affect food choices include the physical and social environments, quality, quantity, perceived healthfulness, and convenience. The personal food choice process was defined as the procedures used by athletes for making food choices, including the weighing and balancing of activities of daily life, physical well-being, convenience, monetary resources, and social relationships.

Objective:

To develop a theoretical model explaining the personal food choice processes of collegiate football players.

Design:

Qualitative study.

Setting:

National Collegiate Athletic Association Division II football program.

Patients or Other Participants:

Fifteen football players were purposefully sampled to represent various positions, years of athletic eligibility, and ethnic backgrounds.

Data Collection and Analysis:

For text data collection, we used predetermined, open-ended questions. Data were analyzed using the constant comparison method. The athletes'' words were used to label and describe their interactions and experiences with the food choice process. Member checks and an external audit were conducted by a qualitative methodologist and a nutrition specialist, and the findings were triangulated with the current literature to ensure trustworthiness of the text data.

Results:

Time was the core category and yielded a cyclic graphic of a theoretical model for the food choice system. Planning hydration, macronutrient strategies, snacks, and healthful food choices emerged as themes.

Conclusions:

The athletes planned meals and snacks around their academic and athletic schedules while attempting to consume foods identified as healthful. Healthful foods were generally lower in fat but high in preferred macronutrients. High-protein foods were the players'' primary goal; carbohydrate consumption was secondary. The athletes had established plans to maintain hydration. Professionals may use these findings to implement educational programs on food choices for football players.     

Electrophysiological properties of neurons in the robust nucleus of the arcopallium of adult male zebra finches

Nucleus robust arcopallium (RA) of the songbird is a distinct forebrain region that is essential for song production. To explore the electrophysiological properties, whole cell recordings were made from adult zebra finch RA neurons in slice preparations. Based on the electrophysiological properties, neurons in RA were classified into two distinct classes. Type I neurons were spontaneously active. They had larger input resistance, longer time constant, larger time-peak of an afterhyperpolarization (AHP), and broader action potentials than those of the other class. A slow, time-dependent inward rectification was induced by hyperpolarizing current pulses in this type of neuron, and was blocked by external CsCl (2mM). Type II neurons had a more negative resting membrane potential than that of type I neurons. They were characterized by a steeper slope of the recovery from the peak of the AHP and frequency-current relationships, a higher firing threshold, and irregular spiking in response to depolarizing current injection.     

肝移植后早期营养支持的评估

背景：大多数肝移植受者移植前后均存在不同程度的营养不良,常规的营养支持治疗方法有肠外营养、肠内营养两种。近年来,营养支持正在向更新、更广的方向发展,代谢调理营养在器官移植中的作用倍受重视。 目的：探索肝移植后早期安全、有效和可行的营养支持治疗方法。 方法：选择肝移植后早期(移植后1~7 d)进行营养支持治疗的受者45例,随机摸球法分成3组,即肠外营养支持组、肠内营养支持组、代谢调理组(肠内营养支持+谷氨酰胺+精氨酸),每组15例,各组营养支持均为等热量和等氮量。通过检测肝功能、测定氮平衡、观察术后营养支持并发症发生等手段,分析比较3种方法的疗效。 结果与结论：纳入患者45例均进入结果分析。与肠外营养相比,肠内和代谢调理营养更能有效地改善受者移植后营养状况,促进移植肝功能恢复;与肠内营养相比,代谢调理营养更有利于改善受者氮平衡,促进蛋白质合成,促进移植肝功能恢复,有其优越性。结果提示,肝移植后早期营养支持治疗,肠内营养和代谢调理营养是安全、有效和可行的。     

E003对RSA模型小鼠蜕膜组织超微结构的影响

目的　观察瑞香素（daphnetin）即E003处理后RSA模型小鼠蜕膜组织形态结构的改变。 方法　建立反复自然流产（recurrent spontaneous abortion,RSA）模型小鼠后,实验分正常妊娠组、RSA模型组、E003低剂量组和E003高剂量组共4组,E003连续灌胃处理14 d后,取蜕膜组织。光镜下观察蜕膜组织血管和细胞形态,电镜下观察蜕膜组织超微结构。 结果　解剖子宫计算胚胎吸收率,E003处理组（低剂量组和高剂量组）低于RSA模型组,差异具有统计学意义,P<0.05;E003高剂量组胚胎吸收率与正常妊娠组相比无统计学差异,P>0.05。光镜下可见RSA模型组蜕膜细胞碎裂,数量较正常妊娠组减少;E003低剂量组和高剂量组蜕膜细胞数量均较模型组增多,排列较整齐。电镜下RSA模型组较正常妊娠组蜕膜细胞体积减小,细胞间隙增大,血管壁不完整,血管内皮细胞结构不完整,细胞核呈梭形;E003低剂量组与模型组比较,蜕膜细胞体积增大,细胞间隙增大,血管壁较完整,血管内皮细胞呈长梭形,细胞结构较完整,细胞间隙稍增宽;E003高剂量组蜕膜细胞组织及血管壁接近正常妊娠组。 结论　RSA模型小鼠存在母胎界面血管生成障碍,E003可修复RSA模型小鼠蜕膜组织中破坏的细胞结构,改善血管生成和细胞器形态,对RSA模型小鼠具有一定的治疗作用。     

金叶女贞花提取物镇痛抗炎活性的筛选及评价

目的:筛选和评价金叶女贞花提取物的镇痛抗炎活性。方法:利用溶剂萃取法制备金叶女贞花水提取物、乙酸乙酯提取物和正丁醇提取物。SPF级昆明小鼠分为5组:空白对照组(control)、阿司匹林组(aspirin)、金叶女贞花水提取物组、金叶女贞花乙酸乙酯提取物组以及金叶女贞花正丁醇提取物组。采用小鼠热板法和冰醋酸扭体法建立小鼠疼痛模型,评价金叶女贞花各提取物的镇痛效果。采用小鼠耳廓肿胀法、小鼠足肿胀法评价金叶女贞花不同提取物的抗炎作用。结果:镇痛实验结果显示,金叶女贞花水提取物能显著提高小鼠痛阈,减少扭体次数(P<0.05),且金叶女贞花水提取物的镇痛率高达63.89%。抗炎实验结果显示,金叶女贞花水提取物、乙酸乙酯提取物和正丁醇提取物均能抑制小鼠耳肿胀和足肿胀,具有显著的抗炎作用(P<0.05)。结论:金叶女贞花兼具镇痛和抗炎活性的物质主要存在于水提取物中。此外,金叶女贞花的乙酸乙酯提取物和正丁醇提取物均具有一定的抗炎活性。     

前列腺癌靶区位移影响因素分析

目的 深层次探究直肠肌肉张力、腹内压和盆腔骨骼3个客观因素对前列腺癌放疗前锥形束CT校准数据影响,得到影响前列腺靶区运动主要因素,为优化放疗计划设计和提高图像引导精度提供参考.方法 依据试验纳排标准,筛选符合条件的10名前列腺癌患者,接受每周两次随机治疗前锥形束CT扫描,获取前列腺靶区校准数据.扫描之后,分别采用剪切波超声弹性成像技术量化患者直肠肌肉张力影响,采用气囊测压表测量膀胱内压间接量化腹内压影响,采用误差均方根量化盆腔骨骼影响.回归分析3个因素与锥形束CT校准数据之间关系.结果 所有患者左右、前后、头脚方向上锥形束CT校准结果分别为:0.513 mm±0.072 mm、1.369 mm±0.162 mm、1.335 mm±0.271 mm;杨氏模量值:8.965 kPa±1.391 kPa、10.211 kPa±1.544 kPa、3.926 kPa±0.693 kPa,腹内压(未分方向):4.844 mmHg±1.347 mmHg(1 mmHg=133.3 Pa),误差均方根:0.020 mm±0.011 mm、0.069 mm±0.049 mm、0.052 mm±0.029 mm;前后方向上直肠肌肉张力(R=0.895)和腹内压(R=0.523)均同锥形束CT校准数据存在统计学意义相关性,头脚方向上腹内压(R=0.717)存在统计学意义相关性.结论 前后方向上直肠肌肉张力和头脚方向上腹内压是造成前列腺癌靶区位移主要因素,结果对优化放疗计划设计和提高图像引导精度具有重要意义,并为未来降低靶区位移提供了方法学指导.