间歇微脉冲超声乳化术对角膜内皮细胞损伤的临床研究

目的 :研究间歇微脉冲模式超声乳化对角膜内皮细胞的影响及不同硬度核病人角膜内皮细胞损伤的差别。方法 :老年性白内障 14 8例 180眼 ,按核硬度随机分为A、B、C三组 ,其中A组小于等于Ⅱ级核 60眼 ,B组Ⅲ级核 60眼 ,C组大于等于Ⅳ级核 60眼。A、B、C每组又随机分为两组 ,即A1、A2 ,B1、B2 ,C1、C2 组 ,其中A1、B1、C1为实验组行间歇微脉冲模式超声乳化 ,A2 、B2 、C2 为对照组行线性模式超声乳化 ,每组术前、术后 0、 2、 6、 12、 2 4、 48小时、 1周、 1月、 3月检查视力 ,裂隙灯检查角膜及前房反应情况 ,行中央区角膜内皮细胞反射显微照相 ,观察角膜内皮细胞形态及数量的变化情况。结果 :术后 2 4小时 ,裸眼视力大于或等于 0 5 :A1组 2 9例 ( 96 7% ) ,A2 组 2 8例 ( 93 3 % ) ,B1组 2 9例 ( 96 7% ) ,B2 组 7例( 2 3 3 % ) ,C1组 2 0例 ( 66 7% ) ,C2 组 5例 ( 1 67% )。术后 2小时各组角膜均透明 ,无后弹力层皱褶。 6小时角膜开始出现水肿 ,C1组 2 0 %病人、B2 组全部病人角膜细线状后弹力层皱褶 ,C2 组大部分可见明显条状后弹力层皱褶 ,部分可见斑块状混浊。 1周基本消退 ,B2 、C2 组一个月消退。术后除C2 组前房有反应外 ,其余无明显炎症反应。角膜内皮细胞形态学轻度改变。角膜内皮细胞损失     

Changes of TGF-β2, MMP-2, and TIMP-2 levels in the vitreous of patients with high myopia

Purpose

To investigate the concentrations of transforming growth factor (TGF)-β2, matrix metalloproteinase (MMP)-2, and tissue inhibitor of metalloproteinase (TIMP)-2 in the vitreous of patients with high myopia.

Methods

Twenty-six patients with high myopia (HM) who received vitrectomy for macular retinoschisis or macular hole were enrolled in this prospective study. Twenty-six patients with idiopathic macular hole or macular epiretinal membrane were chosen as a control group. Vitreous samples were obtained during the vitrectomy surgery. The levels of TGF-β2、MMP-2、TIMP-2 in the vitreous samples were measured by enzyme-linked immunosorbent assay. The MMP activity was determined by a fluorometric assay.

Results

There was no significant difference in the vitreous level of TGF-β2 between HM (1.64?±?0.38 ng/ml) and the control group (1.56?±?0.32 ng/ml, p?=?0.56). The vitreous levels of MMP-2 in HM (32.40?±?14.90 ng/ml) were significantly higher than in the control group (21.42?±?6.74 ng/ml, p?MMP-2/TIMP-2 was significantly elevated in the vitreous samples from HM (0.61?±?0.19), compared to the control group (0.48?±?0.11, p?p?Conclusions The elevated MMP/TIMP ratio and MMP activity may play a role in the pathogenesis of human high myopia. Large prospective studies are needed to further investigate the effect of MMPs in the pathogenesis of human high myopia.     

邻苯二甲酸二丁酯对雌性果蝇生殖能力的双重作用

目的:研究邻苯二甲酸二丁酯(DBP)对雌性果蝇生殖能力的影响。方法:将未交配雌性果蝇随机分为5组,分别给予含DBP0.1%(A组)、0.4%(B组)、1.6%(C组)和6.4%(D组)的培养基喂饲,并以0浓度为对照组(E组),在染毒10d和20d时,分别取存活的实验雌蝇进行交配试验和生育试验。结果:各染毒组雌蝇1h交配率随DBP浓度升高而降低,D组雌蝇的1h交配率和生育率明显低于E组(P<0.05或P<0.01);染毒10d后C组的平均生育数和平均产卵期均明显高于E组(P<0.05),且在连续产卵10d后仍保持较高的生育水平;染毒20d后D组的平均生育数和平均产卵期均明显低于E组(P<0.01)。结论:DBP对雌蝇生殖能力有双重作用,较低浓度可提高雌性果蝇生育力,而较高浓度可使其生育能力降低。     

米非司酮对中期引产母、儿外周血SCE的影响

目的探讨用不同剂量米非司酮（MFT）中期妊娠引产对母、儿姐妹染色单体交换（SCE）频率的影响,评估MFT对人体的染色体稳定性影响。方法选择符合研究条件的中期引产患者120例,随机分为4组：空白对照组,分别口服MFT 150、200、300 mg引产组,于胎儿娩出后取母亲静脉血及胎儿脐带血,进行SCE频率检测比较。结果①母亲组MFT 150 mg组、200 mg组与对照组SCE频率比较差异无统计学意义;300 mg组与对照组SCE频率比较,差异有统计学意义（P〈0.001）;各组均随着用药剂量加大,SCE频率逐渐升高（spearmanr=0.802,P〈0.05.）。②胎儿各组脐血SCE频率与是否用药以及药物剂量差异均无统计学意义（P〉0.05）。结论①小剂量MFT（150、200 mg）引产,不引起母亲SCE频率显著增加。但300 mg引产时,SCE频率显著提高,应引起临床注意。②不同剂量MFT对胎儿SCE频率无影响。     

三种指标产前筛查出胎儿生长迟缓23例

方法利用姐妹染色单体互换频率、B型超声、宫高及腹围三种指标综合判断产前诊断胎儿生长迟缓.目的以提高产前诊断率及建立新的早期诊断方法.结果姐妹染色单体互换频率产前诊断率为61.76%,B型超声为52.94%,宫高腹围为26.09%,姐妹染色单体互换频率阳性检出率为75%,孕20周前阳性检出率为76.19%,三种指标综合判断可使产前诊断率提高到82.19%.结论多种指标判断可以提高产前诊断率,姐妹染色单体互换频率可以作为一项产前诊断胎儿宫内生长迟缓的新指标.     

论数字农业与中药农业

20世纪末,国际上形成了数字农业的概念,以3S技术（遥成（RS）技术、地理信息系统（GIS）技术和全球定位系统（GPS）技术）为基础的数字农业预示着21世纪的农业将呈现出一个以数字化为特征的崭新面貌。它将对农业资源环境、生产状况、气象和生物性灾害等进行有效预测,指导人们根据各种变异情况实时实地采取相应的农事操作。本文概述数字农业的含义和技术体系,阐述数字农业在中药农业中的作用,及其对中药农业发展的影响。     

Numerical Simulation and Process Optimization on Hot Twist-Stretch Straightening of Ti-6Al-4V Alloy Profile

Ti-6Al-4V profiles prepared by hot extrusion are usually accompanied by bending and twisting. The hot twist-stretch straightening is an effective strategy such that the bending deflection and twisting angle can be simultaneously decreased by a single straightening process. In addition, utilizing stress relaxation effect, the residual stress and springback can be greatly reduced by holding the straightening temperature and strain constant for a period after twist-stretch straightening. In this study, the hot deformation behaviors of the Ti-6Al-4V profile were revealed by experiments. The tensile model was obtained by uniaxial tensile tests within ranges of temperatures (500–700 °C) and strain rates (5 × 10⁻⁵–1 × 10⁻³ s⁻¹). The creep constitutive model was acquired with stress relaxation experiments in ranges of temperatures (500–700 °C) and pre-strain of 1.5%. Then, the coupled thermo-mechanical model of hot twist-stretch straightening was established. Based on orthogonal experiment strategy, the effects of straightening temperature, stretch strain, and holding time on the bending deflection and torsion angle of profile were investigated systematically and the process was optimized. The straightening accuracy is significantly affected by straightening temperature and holding time. By using optimized process parameters in practical straightening experiments, the deflection/length and angle/length after straightening does not exceed 2‰ and 2.5‰°/mm, respectively, which is basically consistent with the numerical simulation result.     

Transperineal pelvic drainage combined with lateral position to promote perineal wound healing after abdominoperineal resection: A prospective cohort trial

Background:For the rectal cancer <5 cm from anal margin, extralevator abdominoperineal resection (eAPR) has been accepted widely by surgeons. However, the rate of perineal infection following up eAPR is approximately 70%. We did the study with the aim of evaluating the effect and safety of transperineal pelvic drainage combined with lateral position (TPDLP) on perineal wound in patients undergoing eAPR.Methods:Patients were randomly assigned to N-TPDLP group (standard arm) or TPDLP group (intervention arm). In the standard arm, surgery was completed after abdominal drainage tube was placed in pelvic. Comparatively, an additional transperineal wound drainage tube was applied in the experimental arm. Postoperatively, patients of both 2 groups were informed not to sit to reduce perineal compression until the perineal wound healed. But lateral position was demanded in the intervention arm. The primary endpoint was the rate of uncomplicated perineal wound healing defined as a Southampton wound score of <2 at 30 days postoperatively. Patients were followed for 6 months.Results:In total, 60 patients were randomly assigned to standard arm (n = 31) and intervention arm (n = 29). The mean perineal wound healing time was 34.2 (standard deviation [SD] 10.9) days in TPDLP arm, which significantly differ from 56.4 (SD 34.1) in N-TPDLP arm (P = .001). At 30 days postoperatively, 3 (10%) of 29 patients undergoing TPDLP were classified into grade 4 according to Southampton wound score, however, 16 (52%) of 31 patients were classified into grade 4 in control arm, and significantly difference was observed between randomization groups (P = .001). What''s more, perineal wound pain was assessed at 30 days postoperatively, and it is discovered that the pain degree of patients in control arm was significantly more severe than the interventive arm (P = .015).Conclusion:In the present study, we found that TPDLP generated a favorable prognosis for perineal wounds with acceptable side-effects.     

Using a two-step method of surface mechanical attrition treatment and calcium ion implantation to promote the osteogenic activity of mesenchymal stem cells as well as biomineralization on a β-titanium surface

Surface treatment is known as a very efficient measure by which to modulate the surface properties of biomaterials in terms of grain structure, topography, roughness and chemistry to determine the osseointegration of implants. In this work, a two-step method of surface modification was employed to impart high osteogenic activity and biomineralization capacity on a Ti–25Nb–3Mo–2Sn–3Zr alloy (a type of β-titanium named TLM). The preliminary surface mechanical attrition treatment (SMAT) refined the average grain size from 170 ± 19 μm to 74 ± 8 nm in the TLM surface layer and promoted the surface to be much rougher and more hydrophilic. The subsequent Ca-ion implantation did not change the surface roughness and topography obviously, but enhanced the surface wettability of the SMAT-treated TLM alloy. The in vitro evaluations of the adhesion, proliferation, osteogenic genes (RUNX2, ALP, BMP-2, OPN, OCN and COL-I) and protein (ALP, OPN, OCN and COL-I) expressions, as well as extracellular matrix (ECM) mineralization of mesenchymal stem cells (MSCs) revealed that the initial SMAT-treated sample significantly enhanced the adhesion and osteogenic functions of MSCs compared to an untreated TLM sample, and the subsequent introduction of Ca ions onto the SMAT-derived nanograined sample further promotes the MSC adhesion, proliferation, osteo-differentiation and ECM mineralization due to the adsorption of more proteins such as laminin (Ln), fibronectin (Fn) and vitronectin (Vn) on the surface, as well as the increase in extracellular Ca concentrations. In addition, the biomineralization capacity of the samples was also evaluated by soaking them in simulated bodily fluid (SBF) at 37 °C for 28 days, and the results showed that the Ca-ion implanted sample significantly boosted the deposition of Ca and P containing minerals on its surface, which was associated with the generation of more Ti–OH groups on the surface after ion implantation. The combination of the SMAT technique and Ca-ion implantation thus endowed the TLM alloy with outstanding osteogenic and biomineralization properties, providing a potential means for its future use in the orthopedic field.

Combination of the SMAT technique and Ca-ion implantation produced a β-titanium alloy with a bioactive surface layer, which was proved to effectively promote the osteogenic activity of MSCs and Ca–P mineral deposition in vitro.     

Increased neutrophil count Is associated with the development of chronic kidney disease in patients with diabetes

BackgroundThis study aims to investigate the potential association of peripheral inflammatory blood cell parameters with the incidence and progression of chronic kidney disease (CKD) in patients with diabetes.MethodsThe cross‐sectional study included 1192 subjects with diabetes derived from one center. The cohort study included 2060 subjects with diabetes derived from another two centers followed up for 4 years. Logistic regression and Cox proportional hazards models were used to evaluate the association of peripheral inflammatory blood cell with CKD.ResultsIn the cross‐sectional study, neutrophil count performed best as an independent risk factor for CKD (odds ratio 2.556 [95% confidence interval 1.111, 5.879]) even after 1:1 case–control matching for age, gender, history of high blood pressure and duration of diabetes. Spline regression revealed a significant linear association of CKD incidence with continuous neutrophil count in excess of 3.6 × 10⁹/L. In the cohort study, subjects were grouped based on tertile of neutrophil count and neutrophil‐to‐lymphocyte ratio. Cox regression analysis results showed that only neutrophil count was independently associated with CKD progression (the highest group vs. the lowest group, hazard ratio 2.293 [95% confidence interval 1.260, 4.171]) after fully adjusting for potential confounders. The cumulative incidence of CKD progression in patients with diabetes gradually increased with increasing neutrophil count (53 (7.7%) subjects in the lowest group vs. 60 (8.2%) in the middle group vs. 78 (12.2%) in the highest group).ConclusionsThis study suggested that neutrophil count is an independent risk factor for progression of CKD in patients with diabetes.