生物工程活性角膜基质的研制及相容性研究

研究生物工程活性角膜的生物相容性，为进一步临床应用提供理论基础。猪角膜基质脱细胞并去除免疫源性物质形成网状半透明生物材料，将培养的角膜基质细胞与生物材料复合构建生物工程活性角膜基质。对复合物进行倒置显微镜和扫描电镜检测细胞附着情况及材料的细胞相容性；将活性角膜基质移植入新西兰兔角膜囊袋内．细胞用BrdU标记检测在体内移植过程中的存活及转归，不同时间观察角膜的生物相容性及改建情况。结果显示脱细胞基质材料的细胞相容性较好，细胞种植后可存活、黏附并增殖；移植区细胞可有BrdU阳性着色，4周后角膜开始透明，8周后角膜改建基本完成。     

mPEG表面修饰的PLGA嵌段共聚物的血液相容性评价

本实验室设计合成了三种不同LA／GA比例的mPEG修饰PLGA（PELGA，含15％mPEG），为了评价它们的血液相容性，我们以硅化玻璃试管为阴性对照，未硅化的试管为阳性对照，参照国际标准（ISO10993）和《中华人民共和国国家标准GB／T16886医疗器械生物学评价》方法进行了体外评价实验。试验包括溶血率实验，血小板黏附实验，动态凝血时间实验，凝血时间实验，血浆复钙时间实验和凝血酶原时间实验等综合评价指标。结果表明，合成材料具有优良的血液相容性，材料制成的纳米粒有望应用于静脉注射。     

ERK1/2信号转导途径在低切应力上调人脐静脉内皮细胞IL-8基因表达中的作用

血管内皮细胞位于血流和血管壁之间,除受化学因素的调节外还受力学因素的影响。切应力可通过刺激相应的力学感受系统来调节内皮细胞某些基因的表达,其中包括诱导内皮细胞表达IL- 8。为了阐明MAPK信号途径中的ERK1/ 2信号通路是否参与调控低切应力上调人脐静脉内皮细胞IL- 8基因表达,采用Western blot分析了低切应力(4.2 0 dyne/ cm2 )处理不同时间内皮细胞ERK1/ 2的磷酸化水平及TPK抑制剂Genistein,MEK抑制剂PD980 5 9对其磷酸化的影响;采用定量RT- PCR检测内皮细胞经低切应力刺激或给予阻断剂后再行切应力刺激等处理后IL- 8基因的表达。结果显示:(1)低切应力处理可引起内皮细胞ERK1/ 2蛋白磷酸化水平上调,其磷酸化水平与切应力作用时间有关,具有快速、双向性的特点(在刺激10 min时达到高峰,2 h左右降至未刺激水平) ,阻断剂Genistein和PD980 5 9处理后,ERK1/ 2磷酸化水平与低切应力刺激10 min比较明显降低;(2 )阻断剂Genistein,PD980 5 9可显著抑制低切应力所致的内皮细胞IL- 8m RNA上调。结果表明低切应力可通过ERK1/ 2信号途径上调人脐静脉内皮细胞IL- 8基因的表达。     

Mechanisms by which acute phase proteins enhance development of liver fibrosis: effects on collagenase and prolyl-4-hydroxylase activity in the rat liver

Previous experiments showed that the presence of high levels of acute phase reactants (APR) enhance CCl4-induced liver fibrosis in the rat. A high correlation was found between the degree of fibrosis and alpha 2-macroglobulin of the rat (alpha 2-macrofetoprotein, alpha M-FP) used for monitoring the acute phase response. This acute phase reaction was provoked by epinephrine just before CCl4 treatment was started. In the present study we analyzed the effect of APR by repeating these experiments and estimating liver neutral collagenase with a synthetic substrate and endogenous collagen as a substrate, and liver prolyl-4-hydroxylase. A strong depression of liver collagenase activity was found in rats with a preceding acute phase reaction contrary to the rats that underwent CCl4 treatment only. A high level of alpha M-FP correlated negatively with collagenase activity. Also in vitro alpha M-FP proved to inhibit collagenase activity. Prolyl-4-hydroxylase was increased in the rats during acute phase reaction and correlated highly and positively with alpha M-FP, haptoglobin, and ceruloplasmin. Thus high levels of APR promote development of CCl4-induced fibrosis, partly by anticollagenase activity and partly because of enhancement of prolyl-4-hydroxylase activity. The latter phenomenon can also be explained by the presence of APR, but this has to be proved.     

Correction to: Cichorium intybus L. promotes intestinal uric acid excretion by modulating ABCG2 in experimental hyperuricemia

The study of sex differences in hyperuricemia can provide not only a theoretical basis for this clinical phenomenon but also new therapeutic targets for urate-lowering therapy. In the current study, we aimed to confirm that estradiol can promote intestinal ATP binding cassette subfamily G member 2 (ABCG2) expression to increase urate excretion through the PI3K/Akt pathway. The estradiol levels of hyperuricemia/gout patients and healthy controls were compared, and a hyperuricemia mouse model was used to observe the urate-lowering effect of estradiol and the changes in ABCG2 expression in the kidney and intestine. In vivo and in vitro intestinal urate transport models were established to verify the urate transport function regulated by estradiol. The molecular pathway by which estradiol regulates ABCG2 expression in intestinal cells was explored. The estradiol level of hyperuricemia/gout patients was significantly lower than that of healthy controls. Administering estradiol benzoate (EB) to both male hyperuricemic mice and female mice after removing the ovaries confirmed the urate-lowering effect of estradiol, and hyperuricemia and estradiol upregulated the expression of intestinal ABCG2. Estradiol has been confirmed to promote urate transport by upregulating ABCG2 expression in intestinal urate excretion models in vivo and in vitro. Estradiol regulates the expression of intestinal ABCG2 through the PI3K/Akt pathway. Our study revealed that estradiol regulates intestinal ABCG2 through the PI3K/Akt pathway to promote urate excretion, thereby reducing serum urate levels.     

HbA1C is not directly associated with complications of bariatric surgery

IntroductionBariatric surgery is effective therapy for weight loss and diabetes control. While patients with poorly controlled type 2 diabetes (T2D) experience significant benefit from bariatric surgery, the impact of hyperglycemia on perioperative risks is unclear.ObjectiveThis study aims to investigate effect of elevated glycated hemoglobin (HbA1C) on perioperative risks for patients undergoing sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB).Settings117,644 patients undergoing RYGB or SG between the years of 2017 and 2018 in the United Stated were analyzed. Data was obtained using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database.MethodsThree commonly used cutoff levels of HbA1C were selected (6.5, 7.0, and 8.5). Complications were compared between groups of patients above and below each HbA1C level. Multivariable logistic regression models were used to account for confounders.ResultsWithout risk adjustment, HbA1C is indirectly associated with increased rates of surgical complications. However, after adjusting for underlying co-morbidities, HbA1C is not associated with overall complications, including 30 day readmissions, reoperations, reinterventions, or death at any HbA1C cutoff: 6.5 (odds ratio [OR] 1.041, P value = .219), 7.0 (OR 1.020, P value = .551), or 8.5 (OR 1.051, P value = .208).ConclusionThere is no direct relationship between HbA1C and early postoperative complications of SG and RYGB. Thus, optimizing preoperative HbA1C values alone, may not translate into decreased surgical complications of bariatric surgery. (Surg Obes Relat Dis 2020;17:271–275.) © 2020 American Society for Metabolic and Bariatric Surgery. All rights reserved.     

中国公众公共卫生安全素养量表的开发研究

目的开发公共卫生安全素养量表, 为我国公众的公共卫生安全素养测评提供适宜工具。方法通过理论构想、指标池构建、现场验证、题项缩减等步骤编制中国公共卫生安全素养初始量表, 转为"问卷星"电子问卷, 随机抽取4个省份共2 809名居民进行现场测试。利用经典测试理论(CTT)和项目反应理论(IRT)进行题项缩减。使用SPSS 23.0软件进行探索性因子分析(EFA)和单维性检验。使用R 4.1.1软件ltm和mirt包进行题项的心理测量学指标分析, 并绘制项目特征曲线(ICC)和信息函数曲线(IIC和TIF)。结果选用专家一致性系数最优的初始量表3, 共30个题项(B1～B30), 测试对象完成1个题项平均需9.8 s。根据CTT分析, 删除校正题项-总相关系数(CITC)<0.3及题项-维度相关系数(IDCC)<0.4的B2题项;删除CITC<0.3、IDCC<0.4及难度指数<0.2的B23题项;删除CITC<0.3及难度指数<0.2的B30题项。删除后量表总内部一致性信度(Cronbach’’sα)值为0.923。EFA提示删除14个因子载荷较小...     

The Effect of a PEEK Material‐Based External Fixator in the Treatment of Distal Radius Fractures with Non‐Transarticular External Fixation

ObjectiveTo explore the effect of a PEEK material‐based external fixator in the treatment of distal radius fractures with non‐transarticular external fixation.MethodsThere were 48 patients in this prospective comparative study. They were divided into two groups according to the materials used: the PEEK group and the titanium group. Wrist dorsiflexion, palmar flexion, pronation, supination, radial deviation, ulnar deviation, grip strength of the palm on the affected side, kneading force, Visual Analogue Scale/Score (VAS), Disabilities of the Arm, Shoulder, and Hand (DASH) score, operation time, frequency of fluoroscopy procedures, and X‐ray results were compared between the two groups. Functional recovery was evaluated at the last follow‐up according to the wrist joint evaluation criteria.ResultsThe baseline data were comparable between the two groups, and no significant differences were found in age, sex, fracture types (P > 0.05). There was no significant difference between the two groups in the results of DASH, grip strength, and recovery of pinch force and wrist function (dorsiflexion, clavicle, ulnar deviation, deviation, pronation, and supination) (P > 0.05). Normal limb function was achieved in the two groups of patients at an average of 6 weeks after surgery, and there was no significant difference in X‐ray examination radial height (10.60 ± 1.59 vs 11.00 ± 1.53, P = 0.687), radial inclination (1.11 ± 0.24 vs 1.12 ± 0.24, P = 0.798), volar tilt (10.33 ± 2.13 vs 10.00 ± 2.08, P = 0.660), ulnar variance (20.87 ± 3.00 vs 20.38 ± 3.04, P = 0.748), and step‐off persistence (1.73 ± 0.69 vs 1.68 ± 0.72, P = 0.425) between the two groups (P > 0.05). However, the operation time (54.80 ± 12.20 vs 85.23 ± 15.14, P = 0.033) and number of fluoroscopy procedures (36.93 ± 6.89 vs 64.77 ± 9.74, P = 0.000) in the PEEK group were significantly reduced compared with those in the titanium group.ConclusionCompared with the traditional titanium external fixator, the PEEK composite external fixator has advantages, such as a shorter operation time and fewer fluoroscopy procedures when used to treat different types of distal radius fracture.