PROPELLER DUO DWI序列+常规MRI在直肠癌术前T分期中的应用价值

目的研究螺旋桨采集技术扩散加权成像(PROPELLER DUO DWI)+核磁共振成像(MRI)诊断直肠癌术前T分期的应用价值。方法选取我院2018年6月至2020年6月直肠癌患者65例,均进行MRI及DWI扫描检查,以病理学诊断结果为“金标准”。比较常规MRI与常规MRI+DWI诊断直肠癌T分期的结果及准确率。结果65例直肠癌患者常规MRI诊断T1~T2期33例,T3期22例,T4期10例。MRI+PROPELLER DUO DWI诊断T1~T2期37例,T3期21例,T4期7例。MRI+PROPELLER DUO DWI诊断总准确率为92.3%(60/65),高于MRI[80.0%(52/65,P<0.05)]。结论与MRI常规序列比较,PROPELLER DUODWI技术+常规MRI在直肠癌患者术前T分期诊断中准确率更高,有助于临床治疗方案的制定。     

A simple automated stimulator of mechanically induced arrhythmias in the isolated rat heart

Transient stretching of the ventricle can trigger arrhythmias and evoke ventricular fibrillation, especially when the stimulation occurs in the vulnerable period. To explore the sensitivity of small hearts we used a commercial pressure servo to study the kinetic relationship of left ventricular pressure to excitability and arrhythmias in the rat heart. Stimulation protocols were readily composed on the computer and programmed to vary the stimulus amplitude and timing relative to pacing. The pressure-induced premature ventricular excitations were similar to those observed in larger hearts, but the convenience of using small hearts allows the use of inexpensive transgenic animals to explore the molecular basis of transduction.     

A unique AtSar1D-AtRabD2a nexus modulates autophagosome biogenesis in Arabidopsis thaliana

In eukaryotes, secretory proteins traffic from the endoplasmic reticulum (ER) to the Golgi apparatus via coat protein complex II (COPII) vesicles. Intriguingly, during nutrient starvation, the COPII machinery acts constructively as a membrane source for autophagosomes during autophagy to maintain cellular homeostasis by recycling intermediate metabolites. In higher plants, essential roles of autophagy have been implicated in plant development and stress responses. Nonetheless, the membrane sources of autophagosomes, especially the participation of the COPII machinery in the autophagic pathway and autophagosome biogenesis, remains elusive in plants. Here, we provided evidence in support of a novel role of a specific Sar1 homolog AtSar1d in plant autophagy in concert with a unique Rab1/Ypt1 homolog AtRabD2a. First, proteomic analysis of the plant ATG (autophagy-related gene) interactome uncovered the mechanistic connections between ATG machinery and specific COPII components including AtSar1d and Sec23s, while a dominant negative mutant of AtSar1d exhibited distinct inhibition on YFP-ATG8 vacuolar degradation upon autophagic induction. Second, a transfer DNA insertion mutant of AtSar1d displayed starvation-related phenotypes. Third, AtSar1d regulated autophagosome progression through specific recognition of ATG8e by a noncanonical motif. Fourth, we demonstrated that a plant-unique Rab1/Ypt1 homolog AtRabD2a coordinates with AtSar1d to function as the molecular switch in mediating the COPII functions in the autophagy pathway. AtRabD2a appears to be essential for bridging the specific AtSar1d-positive COPII vesicles to the autophagy initiation complex and therefore contributes to autophagosome formation in plants. Taken together, we identified a plant-specific nexus of AtSar1d-AtRabD2a in regulating autophagosome biogenesis.

Autophagy is a conserved catabolic process characterized by the de novo generation of a double-membrane structure called an autophagosome with a fundamental function in the bulk turnover of cytoplasmic components, including proteins, RNAs, and organelles. Genetic studies in yeast have elucidated the molecular machinery of autophagy, whereby 42 autophagy-related (ATG) genes have been identified (1–3). These ATG genes are highly conserved among eukaryotes but often have multiple isoforms in other higher organisms, in particular in sessile plants. Albeit increasing understanding on the molecular function of Atg proteins in acting hierarchically on the phagophore assembly site (PAS) to produce autophagosomes, the origin of the autophagosomal membrane remains unclear in higher eukaryotes. Furthermore, the dedication of other membranes and machineries in the autophagy pathway remains under investigation.Plant autophagy is known to play important roles in the sessile lifestyle of plants, participating in seed germination, seedling establishment, plant development, hormone responses, lipid metabolism, and reproductive development (4). Plant autophagy research is advancing with findings not only on the counterparts of the yeast/mammalian Atg proteins but also dealing with some plant-unique factors functioning in different steps of autophagosome biogenesis, thereby uncovering novel mechanisms that might or might not be conserved in nonplant species (5). More interestingly, higher plants possess multiple protein isoforms of ATG machinery, whose functional heterogeneity in the autophagy pathway has only recently been unveiled (6).The coat protein complex II (COPII) machinery consists of five cytosolic components: the small GTPase Sar1, the inner coat protein dimer Sec23-Sec24, and the outer coat proteins Sec13-Sec31. These proteins are essential for COPII-coated vesicle formation, which buds from specialized regions of the ER, namely ER exit sites (ERESs) (7). Under nutrient-rich conditions, COPII vesicles mediate anterograde ER to Golgi transport. However, increasing evidence from yeast and mammals suggests that the COPII machinery or even COPII vesicles themselves may contribute to autophagosome formation when cells are starved for nutrients (8–16). Gene duplication events have occurred substantially in sessile plants during evolution, and the importance of distinct paralogs in environmental stress adaptation during plant development has been implied (17). Arabidopsis encodes multiple COPII paralogs in its genome, including five Sar1s, seven Sec23s, three Sec24s, two Sec13s, and two Sec31s (17). Increasing numbers of studies have pinpointed the functional diversity and importance of distinct COPII paralogs in ER protein export (18–23). Nonetheless, the mechanism by which COPII vesicles are redirected to the autophagy pathway upon nutrient starvation, and their roles in autophagosome biogenesis, remains unclear. Furthermore, the participation of specific COPII paralogs in autophagy regulation remains unknown in plants.Here, we report on a role of a specific Sar1 homolog, AtSar1d, that modulates plant autophagosome biogenesis in concert with AtRabD2a. Large-scale proteomic analysis of the ATG interactome has revealed possible mechanistic connections between the ATG machinery and specific COPII components in plants. Cellular and biochemical analyses have shown that the dominant negative (DN) mutant of AtSar1d (AtSar1dDN) specifically perturbs YFP-ATG8 vacuolar degradation upon autophagic induction. Consistently, a transfer DNA (T-DNA) insertion mutant of AtSar1d exhibited starvation-related phenotypes. Notably, AtSar1d regulates autophagosome progression through specific recognition of ATG8e by a previously uncharacterized noncanonical motif. We further identify a plant-unique Rab1/Ypt1 homolog AtRabD2a that colocalizes with AtSar1d and ATG8 upon starvation by transient expression in Arabidopsis protoplasts. A DN mutant of AtRabD2a (AtRabD2aNI) perturbs autophagy flux, while AtRabD2a is indispensable for bridging the AtSar1d-positive COPII vesicles with the ATG1 complex, thus contributing to autophagosome biogenesis in plants. Our study therefore unequivocally demonstrates that the plant-specific COPII machinery regulates autophagosome biogenesis and sheds light on the evolutionary importance of gene duplication events in the plant autophagy pathway.     

Evaluation of the effect of anti–tumor necrosis factor agent use on rheumatoid arthritis work disability: The jury is still out

Objective

To examine the role of anti–tumor necrosis factor (anti‐TNF) agents in predicting work disability in subjects with rheumatoid arthritis (RA).

Methods

We studied 953 subjects with rheumatologist‐diagnosed RA from a US cohort using a nested, matched, case–control approach. Subjects provided data on medication usage and employment every 6 months for 18 months, were employed at baseline, and were age <65 years at last followup. Cases were subjects who were not employed at followup (n = 231) and were matched ～3:1 by time of entry into the cohort to 722 controls who were employed at followup. Risk of any employment loss, or loss attributed to RA, at followup as predicted by use of an anti‐TNF agent at baseline was computed using conditional logistic regression. Stratification on possible confounding factors and recursive partitioning analyses were also conducted.

Results

Subjects' mean age was 51 years, 82% were female, 92% were white, and 72% had more than a high school education. Nearly half (48%) used an anti‐TNF agent at baseline; characteristics of anti‐TNF agent users were similar to nonusers. In the main analyses, anti‐TNF use did not protect against any or RA‐attributed employment loss (odds ratio [95% confidence interval] 1.1 [0.7–1.6] versus 0.9 [0.5–1.5]). However, a protective effect was found for users with disease duration <11 years (odds ratio [95% confidence interval] 0.5 [0.2–0.9]). In recursive partitioning analyses, age, RA global severity, and functional limitation played a much greater role in determining employment loss than anti‐TNF agent use.

Conclusion

Anti‐TNF agent use did not protect against work disability in the main analyses. In stratified analyses, their use was protective among subjects with shorter RA duration, whereas in nonparametric analyses, age and disease factors were the prominent predictors of work disability.     

支气管哮喘患者外周白细胞糖皮质激素的受体变化

用放射配基结合分析法测定了外源性及内源性哮喘患者外周白细胞糖皮质激素受体（ＧＣＲ）水平，同时测定其血浆皮质醇水平。结果发现哮喘患者ＧＣＲ水平较正常对照组明显降低（Ｐ＜０．０１），其降低程度与疾病初发年龄、病程密切相关，而哮喘患者血浆皮质醇水平与正常对照组无显著差异性。提示哮喘患者肾上腺皮质功能尚未受到明显损害，但其ＧＣＲ功能存在异常。关于哮喘患者ＧＣＲ功能异常原因，我们推测与哮喘患者遗传倾向有关，同时与环境因素反复刺激、疾病反复发作有关。     

延迟增强MRI评估基质诱导自体膝关节软骨移植术效果

目的 探讨延迟增强MRI对基质诱导自体膝关节软骨移植术的临床评估效果.方法 随机选取我院2012年1月至2014年2月期间收治的行自体膝关节软骨移植术患者45例作为实验组,另选取同期软骨损伤患者45例作为对照组,对两组患者进行MRI扫描,对扫描结果进行对比分析.结果 实验组患者术后CR值(0.92±0.08)较术前(1.33±0.15)明显降低,且随着患者病情分级的不断升高,其CR也随之增高(P＜0.05);各部位的MRI增强扫描结果明显优于平扫,差异具有统计学意义(P＜0.05).结论 对基质诱导自体膝关节软骨移植术患者进行MRI增强扫描,能够为临床诊断提供高质量的膝关节软骨检查图像,同时通过对手术前后软骨强化率进行分析,有助于对手术效果进行有效评估.     

GC-MS法分析蛇床子的脂溶性成分

〗摘 要 目的： 研究蛇床子的脂溶性成分。方法: 用索氏提取法提取蛇床子的脂溶性成分,甲酯化处理后,采用气相色谱 质谱联用技术首次对其脂溶性成分进行分析和鉴定。结果: 从蛇床子中鉴定了39个化合物,占蛇床子脂溶性成分的85.33%,蛇床子主要的脂溶性成分为植物醇(15.98%)、棕榈酸(12.73%)、9,12,15 十八碳三烯酸(11.02%)、油酸(6.33%)和9,12 十八碳二烯酸(4.77%)。结论:植物醇、棕榈酸、9,12,15 十八碳三烯酸和油酸是蛇床子的活性成分。     

狗皮膏(改进型)质量标准研究

目的:修订提高狗皮膏(改进型)的质量标准。方法:用薄层色谱法对狗皮膏(改进型)中当归进行定性鉴别;用气相色谱法对狗皮膏(改进型)中冰片、薄荷脑及水杨酸甲酯进行定性鉴别,并测定处方中冰片、薄荷脑及樟脑的含量;用高效液相色谱法测定处方中盐酸苯海拉明的含量。结果:当归的薄层色谱鉴别斑点清晰,重现性好,无干扰;龙脑在0.03~0.26μg,薄荷脑在0.07~0.71μg,樟脑在0.05~0.46μg,盐酸苯海拉明在0.56~5.59μg范围内线性关系良好,各成分平均回收率分别为99.74%(龙脑)、99.10%(薄荷脑)、99.08%(樟脑)、96.95%(盐酸苯海拉明)。结论:修订后的质量标准简便易行,可有效控制狗皮膏(改进型)的质量。     

A rare case report of an solitary neurofibroma in postcricoid region of hypopharynx

Rationale:Postcricoid neurofibroma is an extremely rare hypopharynx tumor that can be challenging in both diagnosis and treatment. This case sheds light on the possibility of treatment with transoral microsurgery before pursuing open cervical incisions.Patient concerns: A 43-year-old man presented with a four months history of a persistent foreign body sensation and mild dysphagia. Indirect and direct laryngoscopy at admission revealed a round and smooth submucosal mass in the postcricoid region.Diagnosis:A laryngeal enhanced computed tomography and laryngoscopy suggested that the tumor located in hypopharynx, with clear boundary and slightly strengthened edge. A supporting laryngoscopy surgery was performed under general anesthesia and a biopsy confirmed solitary neurofibroma of the postcricoid region.Interventions:The tumor was successfully resected en bloc transorally through supporting laryngoscope, and obviated the need for open cervical surgery and tracheostomy.Outcomes:The patient recovered well without any intraoperative or postoperative complication and was discharged from hospital 2 days after surgery. There was no recurrence after 6 months follow-up.Lessons:Postcricoid neurofibroma is an extremely rare hypopharynx tumor that can be diagnostically challenging. To the best of our knowledge, this is the first case reported of solitary neurofibroma originating from the postcricoid region of the hypopharynx and was surgically removed with transoral surgery through supporting laryngoscope.     

Impact of the polymorphism in vitamin D receptor gene <Emphasis Type="Italic">BsmI</Emphasis> and the risk of systemic lupus erythematosus: an updated meta-analysis

The etiology of system lupus erythematosus (SLE) still remains unclear, and vitamin D is associated with immune response. Although a few studies are conducted to investigate the association between polymorphism in vitamin D receptor (VDR) genes and SLE risk, their results are conflicting. Following the guideline of PRISMA, we conducted a systematic search and meta-analysis of the BsmI polymorphism rs1544410 and the risk of SLE. The pooled odds ratios (OR) and its 95 % confidential interval (CI) were calculated by using Stata Version 10 with dominant and recessive model and allele analyses. Nine studies were included in our meta-analysis with a total of 1247 SLE cases and 1687 controls. No significant association was found in both models in the overall population. Only Bb?+?BB genotypes showed a significantly elevated SLE risk in Asian subgroup with an OR of 3.26 (95 % CI?=?1.30–8.17) while no significance was observed in Caucasian population. Notably, B allele significantly increased the SLE risk among Asian population with an OR of 2.29 (95 % CI?=?1.14–4.61). No positive findings were reported in Caucasian population and in the overall analysis. In Asian population, Bb?+?BB genotype and B allele can significantly increase the SLE risk.