Performance and comparison of the Cockcroft-Gault and simplified Modification of Diet in Renal Disease formulae in estimating glomerular filtration rate in a Chinese Type 2 diabetic population.

AIMS: Our aim was to assess performances of the Cockcroft-Gault and simplified Modification of Diet in Renal Disease (MDRD) formulae in estimating glomerular filtration rate (GFR) in Chinese diabetic populations and their association with vascular risks. METHODS: A total of 1009 patients with Type 2 diabetes were categorized into low estimated GFR groups (GFR < 60 ml/min/1.73 m(2)) and control groups by the two equations. The performances of these formulae were assessed at different stages of kidney function. Carotid artery intima-media thickness (IMT) and the prevalence of diabetic retinopathy or albuminuria were compared among the groups. The ability of these formulae to identify established vascular risk markers using sensitivity, specificity, positive and negative predictive values were also compared. RESULTS: The prevalence of low estimated GFR was 32.7% with the Cockcroft-Gault formula and 5.2% with the MDRD formula, respectively. In low estimated GFR subjects by the MDRD formula, IMT was significantly thicker than those by the Cockcroft-Gault formula (1.2 mm vs. 1.0 mm; P < 0.05), with a higher prevalence of albuminuria (78.4 vs. 52.8%, P < 0.05) and diabetic retinopathy (46.5 vs. 30.5%; P < 0.05). The Cockcroft-Gault formula gave a specificity of 71.7% and a sensitivity of 37.0%, and the MDRD formula gave a specificity of 96.6% and a sensitivity of 7.9% in estimating low GFR relevant for established vascular risks. CONCLUSIONS: These formulae performed differently in Chinese diabetic populations. The simplified MDRD formula is minimally superior to the Cockcroft-Gault formula for its high specificity and positive predictive values in estimating low GFR relevant for vascular risks.     

上睑下垂的术前评估及改良提上睑肌缩短术矫治的疗效评价

目的评价改良提上睑肌缩短术矫治上睑下垂的效果。方法采用改良提上睑肌缩短术[此改良术式与常规术式不同之处在于增加分离提上睑肌腱膜的长度(22mm)和宽度(16mm),腱膜在睑板上固4对缝线,以增加其牢固度],共治疗上睑下垂57例68眼,其中轻度13例13眼,中度38例47眼,重度6例8眼。结果术后4～36个月随访,治愈48例59眼,欠矫9例9眼,无过矫病例。结论该提上睑肌缩短术与常规手术比较有改进,术后的睑缘高度易保持在上方角膜缘,弧度与健侧对称,不易形成眼角畸形,能较好提高矫治效果。     

聚丙烯改性研究

采用马来酸酐、二甲基丙烯酸乙二醇酯、三羟甲基丙烷三基丙烯酸酯对聚丙烯进行改性。以自由基反应机理为基础，讨论了引发剂用量、反应时间、改性试剂的种类、用量等因素对改性ＰＰ凝胶含量及性能的影响，提出了力学性能的优选条件。得到了力学性能优良的改性ＰＰ，为其进一步功能化提供了理论参考。     

Factors affecting antibody responses to immunizations in infants born to women immunized against pertussis in pregnancy and unimmunized women: Individual-Participant Data Meta-analysis

BackgroundExploring factors that affect immune responses to immunizations in infants born to women immunized with tetanus-diphtheria-acellular-pertussis (Tdap) in pregnancy compared with unimmunized women is important in designing immunization programs.MethodsIndividual-participant data meta-analysis of 8 studies reporting post-immunization immunoglobulin G (IgG) levels to vaccine antigens in infants born to either women immunized with Tdap in pregnancy or unimmunized women, using mixed-effects models.ResultsIn infants of Tdap-immunized women, two-fold higher levels of anti-pertussis toxin (PT) and anti-diphtheria-toxoid (DT) IgG pre-primary immunization were associated with 9% and 10% lower post-primary immunization levels, (geometric mean ratio [GMR], PT: 0.91; 95% CI, 0.88–0.95,n = 494, DT: 0.9; 0.87–0.93,n = 519). Timing of immunization in pregnancy did not affect post-primary immunization anti-Bordetella pertussis, anti-tetanus-toxoid (TT) and anti-DT IgG levels. Spacing of infant immunization did not affect post-primary immunization anti-B. pertussis and anti-DT levels. In infants of Tdap-immunized women, two-fold higher levels of anti-PT and anti-filamentous haemagglutinin (FHA) IgG pre-primary immunization were associated with lower post-booster immunization levels, (GMR, PT: 0.91; 0.85–0.97,n = 224, FHA: 0.92; 0.85–0.99,n = 232). Timing of immunization in pregnancy did not affect post-booster immunization anti-Bordetella pertussis, anti-tetanus-toxoid (TT) and anti-DT IgG levels. Spacing of infant immunization did not affect post-booster immunization anti-PT, anti-pertactin (PRN), anti-TT and anti-DT IgG levels.In infants of unimmunized women, two-fold higher IgG levels of some vaccine antigens pre-primary immunization were associated with 8–17% lower post-primary immunization levels (GMR, PT 0.92, 95% CI:0.88–0.97, n = 373; FHA:0.88, 95% CI:0.85–0.92,n = 378; PRN:0.84, 95% CI:0.81–0.88, n = 367; TT:0.88, 95% CI:0.83–0.93, n = 241; DT: 0.83, 95% CI:0.79–0.87,n = 278). Two-fold higher levels of anti-FHA IgG pre-primary immunization were associated with 8% lower post-booster immunization levels (GMR, 0.92; 95% CI: 0.86–0.99,n = 138).DiscussionIncreased IgG levels pre-primary immunization is associated with reduced post-primary and post-booster immunization levels for some antigens in infants of women immunized or unimmunized in pregnancy, but their clinical significance is uncertain.     

Chemical modification of arginine residues of Notechis scutatus scutatus notexin.

Notexin, a presynaptic phospholipase A2 (PLA2) neurotoxin isolated from Notechis scutatus scutatus venom, was inactivated by arginine-specific reagents, phenylglyoxal and 1,2-cyclohexanedione. Kinetic analyses of the modification reaction revealed that the inactivation of notexin followed pseudo-first order kinetics and the loss of PLA2 activity was correlated with the incorporation of one molecule of modification reagent per toxin molecule. However, the results of amino acid analysis and sequence determination revealed that two arginine residues at positions 43 and 79 of notexin were modified simultaneously. Modification of the arginine residues was accompanied with a decrease in the ability to inhibit the indirectly evoked contraction of chick biventer cervicis muscle and bind with synaptic membranes. The secondary structure of the toxin molecule did not significantly change after modification with phenylglyoxal as revealed by the CD spectra. The modified derivative retained its affinity for Ca2+, indicating that the modified arginine residues did not participate in Ca2+ -binding. Together with the notion that Arg-43 and Arg-79 of notexin are located in the proximity of its catalytic site and toxic site, respectively, our results suggest that modification of Arg-43 and Arg-79 should differently contribute to the observed decrease in the PLA2 activity and neurotoxic effect of notexin.     

聚乙二醇化生长激素释放激素的研究进展

生长激素释放激素（growth hormone-releasing hormone,GHRH）又称生长激素释放因子（growth hormone-releasing factor,GRF）,是由下丘脑分泌的一种肽类激素,具有促进垂体促生长素细胞合成和释放生长激素（growth hormone,GH）的作用,临床上可以用来治疗矮小症、HIV相关的脂肪营养不良、代谢综合征、艾滋病、创伤等疾病。然而GHRH应用到临床上的最大不足就是体内半衰期比较短（一般10～20min）。为了延长GHRH在体内的半衰期,减少频繁用药给患者带来的不适,须对GHRH进行修饰,以期达到半衰期显著延长,免疫原性有所降低。为此,本文主要综述了GHRH以及GHRH长效修饰的研究进展,尤其是PEG修饰GHRH的最新进展。     

采用改良L型切口行甲状腺癌颈清扫术

目的：探索更加美观隐蔽的甲状腺癌颈清扫术手术切口。方法将2009年1月～2012年12月在我院接受颈清扫术的72例甲状腺癌颈淋巴结转移患者采用改良L型切口进行手术。其中22例患者行甲状腺全切术＋患侧Ⅰ～Ⅵ区颈清扫术;另50例患者单纯行颈清扫术,清扫范围主要为Ⅰ～Ⅴ区淋巴结。颈清扫切口行于斜方肌表面发际前缘自乳突尖后向下行至锁骨上约1.5cm处循皮纹横行向前至颈前中部或与原甲状腺手术切口相连。其中根治性颈清扫术4例,功能性颈清扫术68例。结果72例患者共行83侧颈清扫术,均行改良L型切口。手术过程均顺利,术野暴露满意,手术时间为128～196min,平均145.3±23.8min。共11例患者出现术后并发症,其中颈部积液6例、副神经损伤3例、乳糜漏2例。无皮瓣坏死、切口感染等并发症发生。术后患者颈部切口瘢痕隐蔽,外观影响小。术后随访6个月～4年,淋巴结复发率为0.0%。结论采用改良L型切口行颈清扫术暴露满意,手术并发症少,术后切口隐蔽,是甲状腺癌颈清扫术一种较为理想的手术入路。     

SiO2包覆壳层对Y2O3:Yb3+,Ho3+纳米粒子上转换发光性能的影响

目的:探索提高纳米粒子上转换发光的方法。方法:采用Stber方法,将SiO2壳层包覆在Y2O3:Yb3+,Ho3+纳米粒子表面;采用TEM、XRD和荧光光谱等方法研究表面包覆前后其上转换发光性能。结果:纳米粒子表面包覆SiO2壳层会改善Y2O3:Yb3+,Ho3+纳米粒子的上转换发光强度。结论:结论:SiO2包覆的Y2O3:Yb3+,Ho3+纳米粒子可作为生物荧光标记物应用于医学诊断。