The effect of minimal concentration of ethylene glycol (EG) combined with polyvinylpyrrolidone (PVP) on mouse oocyte survival and subsequent embryonic development following vitrification

Purpose

Vitrification techniques employ a relatively high concentration of cryoprotectant in vitrification solutions. Exposure of oocytes to high concentrations of cryoprotectant is known to damage the oocytes via both cytotoxic and osmotic effects. Therefore, the key to successful vitrification of oocytes is to strike a balance between the usage of minimal concentration of cryoprotectant without compromising their cryoprotective actions.

Methods

The minimal concentration of ethylene glycol (EG) on mouse oocyte survival and subsequent embryonic development was evaluated following vitrification-warming and parthenogenetic activation. Polyvinylpyrrolidone (PVP) combined with EG on mouse oocyte survival and subsequent embryonic development as well as morphology of the spindle and chromosome alignment were also evaluated. Vitrification system was adapted with JY Straw and the cooling rate was approximately 442–500 °C/min. In contrast, the warming rate was approximately 2,210–2,652 °C/min.

Results

Survival rate of oocytes increased significantly when 15 % EG was combined with 2 % PVP in vitrification solution (VS). The effect of combination of EG and PVP was not significant when the concentration of EG was 20 % and higher. Although there were no significant differences in embryonic development, the percentage of abnormal spindle and chromosome alignment was significantly higher in the oocytes without 2 % PVP in VS.

Conclusions

Our data provide a proof of principle for oocyte vitrification that may not require a high concentration of cryoprotectant. There are synergic effects of EG combined with PVP for oocyte vitrification, which may provide important information to the field in developing less cytotoxic VS.     

Can poly(acrylic) acid molecular weight mixtures improve the compressive fracture strength and elastic modulus of a glass-ionomer restorative?

Objectives

To optimize the compressive fracture strength (σ) and elastic modulus (E) of a glass-ionomer (GI) restorative using poly(acrylic) acid (PAA) weight average molecular weight (M_w) mixtures.

Methods

174 PAA solutions were prepared (four control PAA M_ws at three PAA concentrations (25, 35 and 45%) (n = 12) and six M_w mixtures (Groups A-F at nine blend ratios and three PAA concentrations (n = 162))). The viscosity (η) of each PAA solution was determined using a digital viscometer. The PAA solutions were hand-mixed with a commercial GI restorative powder (Ionofil Molar; Voco, Cuxhaven, Germany) and σ and E were determined using cylindrical (6 mm height, 4 mm diameter) specimens (n = 20) at 24 h. Data were analyzed using analyses of variance (ANOVA) (three-, two- and one-way) and regression analyses at p < 0.05.

Results

The three- and two-way ANOVAs highlighted significant effects of M_w mixture, blend ratio and PAA concentration (all p < 0.0001) on the η, σ and E data. Regression analyses showed significant increases in η, σ and E (p < 0.0001) with increasing M_w from Groups A to F. There was no significant effect of blend ratio on the σ data for Groups A (p = 0.178), D (p = 0.747) and F (p = 0.107) and on the E data (p > 0.083).

Significance

The current approach to improving the mechanical properties of GI restoratives using PAA M_w mixtures is encouraging, however, further manipulation of the GI restorative system by optimizing PAA M_w mixtures, blend ratios and PAA concentrations is required to elicit further improvements in σ and E without impacting upon the η of the PAA solution.     

葛花枳椇子配伍使用对醉酒小鼠体内乙醇代谢过程的影响

目的:通过检测急性乙醇中毒小鼠体内乙醇浓度、乙醇脱氢酶(ADH)、乙醛脱氢酶(ALDH)的在不同时间的变化水平,探讨葛花枳蓂子配伍应用是否优于单独使用。方法:将ICR小鼠分为空白组、模型组、阳性药组、单用葛花、枳蓂子组及配伍1、2、3组。选取预防给药的方法,即给药30min后灌酒复制模型,分别于酒后05h,1h,2h,3h摘眼球取血及肝脏组织。酶法测定酒后不同时间点小鼠血中乙醇浓度、肝中ADH和ALDH水平。结果:醉酒小鼠血中乙醇浓度在2h达到峰值,葛花、枳蓂子配伍1、2、3组小鼠体内乙醇浓度均较模型组显著降低(P0.05);小鼠肝脏中ADH水平在1h达峰,配伍2、3组可显著升高小鼠酒后1h肝脏中ADH的水平(P0.05),在2h、3h后,只有配伍3组效用较为明显(P0.05);小鼠肝脏中ALDH水平在2h到达峰值,配伍3组可显著增加其水平,其余各组有增加的趋势但差异无统计学意义。结论:葛花、枳蓂子配伍使用效果优于单独应用,可降低酒后不同时间点小鼠血中乙醇浓度,其机制可能与激活肝脏中ADH与ALDH活性有关,从而起到预防醉酒的作用。     

An Evaluation of the Accuracy of Labeling of Percent Sodium Hypochlorite on Various Commercial and Professional Sources: Is Sodium Hypochlorite from These Sources Equally Suitable for Endodontic Irrigation?

Introduction

The shelf life of sodium hypochlorite (NaOCl) is limited, and a previous article showed that there can be a discrepancy between the expected concentration of free available chlorine (FAC) and the actual FAC concentration in NaOCl solutions intended for endodontic irrigation. The current study investigates the FAC content of domestic and professional NaOCls and evaluates the influences of dilution and storage on FAC concentration.

Methods

First, domestic and professional NaOCls not obtained from manufacturers were iodometrically titrated. Then, NaOCls were diluted with demineralized water or tap water and stored at 4°C or 18°C and analyzed at baseline and 2 and 22 weeks. Statistical analyses included paired samples, independent samples t tests and repeated multivariate analysis of variance. Correlations were calculated with the Pearson or Spearman rank correlation test. A P < .05 was considered significant.

Results

Label specifications of domestic NaOCl were very imprecise (ie, <5% NaOCl). Domestic NaOCl contained 1.8%–3.5% NaOCl (w/v). Professional NaOCl varied from 14.3% relative less FAC than specified on the label to 23.5% relative more FAC than specified. After 22 weeks, the relative average loss of FAC in all conditions was 5.4% FAC (P = .002). Dilution, diluents, or storage temperature had no effect on the decline of FAC caused by aging.

Conclusions

There is a great variation in NaOCl concentrations, with domestic NaOCl being the least accurate. NaOCl can be stored up to 5 months. The FAC concentration of domestic NaOCl is unpredictable, and, therefore, it appears less suitable for clinical application as root canal irrigant.     

应用集中度和圆形分布分析保山市流行性乙型脑炎的时间分布特征

目的 探讨保山市2005-2014 年流行性乙型脑炎发病的时间分布特征。方法 应用集中度和圆形分布法对保山市 2005-2014 年流行性乙型脑炎疫情资料进行处理、分析。结果 2005-2014年保山市流行性乙型脑炎发病时间分布的集中度M=0.818, 圆形分布r=0.820, 平均角ā=203.87, Z=205.08, P0.0001, 发病高峰日为第238日, 流行高峰期是200～274日。结论 保山市2005-2014 年流行性乙型脑炎发病有很强的季节性, 集中度和圆形分布指标可以较为准确地反映保山市乙型脑炎的流行高峰及流行时间。     

Effects of different concentrations of atropine eye drops on guinea pigs with form-deprivation myopia

ObjectiveTo study the effects of different concentrations of atropine eye drops on guinea pigs with form-deprivation myopia; to analyze the potential mechanisms of atropine. MethodsIn this experimental study, 80 3-week-old guinea pigs weighing approximately 100 g were randomly assigned to 5 groups： 4 weeks of monocular form deprivation （n=8）, 4 weeks of form deprivation and atropine （n=8 for each concentration subgroup）, 4 weeks of form deprivation and 2 weeks of atropine （n=8 for each concentration subgroup）, 4 weeks of atropine （n=6 for each concentration subgroup）, and a control group（n=6）. Pure atropine powder was dissolved in distilled water to create three different concentrations of atropine solution： 0.2%, 1.0%, 3.0%. The atropine eye drops were applied once every morning at 8∶30-9∶00. All the groups underwent biometric measurements （refraction, corneal curvature, axial length, etc.） at three timepoints： prior to the experiment, 2 weeks into the experiment, and at the end of the experiment. Immunofluorescence was used to mark the guinea pig retinal cells that had a positive expression of glucagon. The results were analyzed with a paired-sample t test and two-way repeated measures ANOVA. ResultsAfter 2 weeks of form deprivation in the monocular form-deprived group, the experimental eyes developed myopia with a deepening of the vitreous chamber and an elongation of the ocular axis compared to the contralateral eyes. The difference was statistically significant （t=-11.09, 7.89, 3.73, P<0.05）. Four weeks later, the experimental eyes had an even greater myopic shift. In the group with 4 weeks of form deprivation and atropine, there were no significant differences after 2 weeks when changes in refraction, vitreous chamber depth and axial length were compared between the experimental eyes and contralateral eyes of all three subgroups. Furthermore, there were no statistically significant differences between the contralateral and experimental eyes in each subgroup compared to the monocular form-deprived group （F=26.335, 6.479, 6.910, P<0.05）. After 4 weeks, in the group with 4 weeks of form deprivation and atropine, the experimental eyes in all three subgroups began to develop myopia compared to the contralateral eyes （t=-4.67, -7.54, -2.78, P<0.05）. Meanwhile, the vitreous chamber was deepening and the axis was elongating, but there were still statistically significant differences between the contralateral and experimental eyes of each subgroup compared to the monocular form-deprivation group （F=16.962, 5.193, 6.882, P<0.05）. However, there were no significant differences for any refractive parameter among all three subgroups. There was no statistically significant difference for any refractive parameter when the experimental/contralteral eyes of each subgroup in the group with 2 weeks of form deprivation plus 2 weeks of atropine were compared to the group with 4 weeks of form deprivation. None of the guinea pig retinal cells in any group were marked to have a positive expression of glucagon. ConclusionThe 3% concentration atropine eye drops can partly inhibit form-deprivation myopia by preventing the deepening of the vitreous chamber and elongation of the ocular axis in guinea pigs, and the effect of atropine does not show a concentration-dependent pattern. The use of atropine during the latter stage of form deprivation cannot limit the progress of myopia. Glucagon is not involved in the effect of atropine on the development of form-deprivation myopia in guinea pigs.     

家蝇抗菌肽对 FBL－3红白血病原代细胞增殖影响浓度的探索

本文初步探究不同浓度家蝇幼虫抗菌肽对FBL－3红白血病原代细胞增殖的影响。采用诱导、研磨、离心、 C18固相萃取等方法制备家蝇幼虫抗菌肽混合物,然后处理传代期的FBL－3细胞,调整浓度为2．25×106／mL并通过尾静脉注射C57BL／6小鼠,建立红白血病动物模型。待肿瘤生长较大时,处死并剥离肿瘤,再通过研磨、裂红液裂解、获取原代肿瘤细胞并培养。将抗菌肽混合物调整为不同浓度作用于传代期的FBL－3原代细胞,之后经倒置显微镜观察照相,台盼蓝染色试验计算死亡率、 CCK－8试剂盒做细胞毒性检测。结果显示抗菌肽混合物浓度为250～350μg／mL作用FBL－3原代细胞时,细胞碎片大量增多,死亡率增高,细胞毒性变大。初步证明了抗菌肽混合物在250～350μg／mL抑制细胞增殖效果明显,在300μg／mL浓度下抑制作用最强,本研究结果可作为动物模型体内实验的参考。     

双氯芬酸钠对大鼠骨髓间充质干细胞影响的浓度、时间效应

目的通过不同浓度的双氯芬酸钠干预体外培养的大鼠骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs),观察其对大鼠骨髓间充质干细胞增殖、凋亡及成骨分化能力的影响;不同药物干预时间对细胞成骨分化能力的影响。方法不同浓度的双氯芬酸钠(6.4、3.2、1.6、0.8、0.4mg/L)干预第4代(P4)BMSCs,通过MTS法检测细胞增殖活性;AnnexinⅤ-FITC法检测细胞凋亡;根据茜素红染色钙结节的数量,初步检测细胞成骨能力。并选取1.6mg/L的药物浓度,不同时间点和时长进行干预,检测细胞成骨分化能力的变化。结果随着双氯芬酸钠浓度的升高,BMSCs细胞增殖活性逐渐降低,细胞凋亡比率升高,钙结节数量减少。药物在第1~14天期间干预能够减少钙结节的形成,在第14~21天期间干预对钙结节的形成无明显影响。结论双氯芬酸钠可影响BMSCs的增殖、凋亡及成骨分化能力,且呈浓度和时间依赖性,短期的作用效果是部分可逆的。     

0.1％他克莫司软膏治疗青少年寻常型银屑病临床疗效观察

目的观察应用0.1%他克莫司软膏治疗青少年寻常型银屑病的临床疗效。方法选取我中心皮肤病性病门诊部治疗的寻常型银屑病未成年患者66例,利用随机数表法分为两组,每组33例,观察组应用0.1%他克莫司软膏治疗,对照组应用卤米松乳膏治疗,选取治疗前、治疗2周、治疗4周、治疗8周为观察点,比较两组患者皮损面积及严重程度的改善情况,并评价疗效。结果治疗2周、4周、8周,与治疗前相比,观察组患者的PASI(银屑病面积与严重性指数)改善水平均显著优于对照组(P <0.05);治疗期间,观察组不良反应率为6.1%,也明显低于对照组15.2%(P <0.05)。结论 0.1%他克莫司软膏用于治疗青少年寻常型银屑病安全有效,且副作用小,值得临床应用。