Maternal aggression: new insights from Egr-1

Lactating mice display fierce aggression towards novel, male mice. This study compares neuronal activity in the brains of aggression-tested (T) and -untested (U) mice using early growth response factor 1 (Egr-1; also known as Krox 24, NGFI-A, Zif268, Tis8, and ZENK) as a measure of neuronal activity. Animals were sampled 90 min after either a sham or real 7-min test with a male intruder, after which their brains were examined for immunoreactivity to Egr-1 (Egr-IR). Significant increases in Egr-IR in T mice were identified in 11 of 40 brain regions, including paraventricular nucleus of the hypothalamus; anterior and lateral hypothalamus (both posterior portion); ventromedial hypothalamus; lateral periaqueductal gray; and medial, central, and basolateral amygdala. Posterodorsal (MePD) and posteroventral medial amygdala were examined for the first time in association with maternal aggression. MePD, a region associated with both sexual and aggressive behaviors in rats, hamsters, and mice, showed increased Egr-IR in association with testing. Taken together, the results from this study provide new insights into the neural circuits regulating maternal behaviors.     

褐藻胶浆在皮肤外用制剂中的应用——Ⅰ.涂膜材料的研究

本文以自行研制的褐藻胶浆作成膜材料,制备了药物涂膜剂,并以褐藻酸钠,聚乙烯醇的相同药物制剂作对照,进行了抑菌,稳定性,药物释放等实验研究。结果表明,褐藻胶浆是一较理想的皮肤外用制剂新辅料。以该原料制备的制剂治疗渗出性皮肤病,疗效满意。     

不同表面活性剂修饰的汉防己甲素PLGA纳米粒制备表征及体外评价

目的:基于纳米粒的递送系统,以改善天然化合物汉防己甲素对肺癌的功效。方法:选取聚乙烯醇、普朗尼克-F127和双十二烷基二甲基溴化铵3种不同的稳定剂,采用单乳化扩散溶剂挥发法制备载汉防己甲素的PLGA纳米粒,考察不同稳定剂对载药纳米粒粒径、ζ电位以及对肺癌A549细胞摄取的影响。结果:2%,1%和0.1%浓度的PVA、PF127和DMAB制备的纳米粒呈表面光滑、大小均一的球形,粒径范围均控制在180~200nm;药物包封率为50%~60%;体外释放实验显示,在pH 7.4的PBS溶液中3组载药纳米粒均呈现缓慢持续释药;细胞学实验结果表明3组纳米粒给药系统均表现出比药物更强的抗肿瘤活性。结论:对PLGA进行表面修饰制备的纳米载体能使汉防己甲素的给药效率得到明显提升。     

Influence of Nano-SiO2 on the Mechanical Properties of Recycled Aggregate Concrete with and without Polyvinyl Alcohol (PVA) Fiber

In recent years, recycled aggregate concrete (RAC) has become a research hotspot in the field of urban construction because of its resource utilization of construction waste. However, compared with original concrete, its strength is still low, which requires additional nano-SiO₂ (NS) and fiber. In order to study the mechanism of strength improvement of RAC, this paper takes NS and polyvinyl alcohol (PVA) fiber as variable parameters; uniaxial and triaxial compression tests were carried out on RAC with PVA fiber and NS, and the mechanical properties of RAC were investigated The result shows that within the range of 3% NS content, an increase in the NS substitution rate causes the mechanical properties of RAC to improve significantly. The compressive strength of RAC increases again after adding PVA fiber; through a SEM (scanning electron microscopy) analysis of the specimen, it was found that the NS filled the micro-pores and micro-cracks in the RAC, and the PVA fiber changed the contact range between recycled aggregate and mortar, so the microstructure of the material was more compact. The mechanism of RAC strength improvement is explained in the microcosmic view.     

聚乙烯醇水凝胶的生物相容性评价

背景：聚乙烯醇水凝胶作为烧伤创面的修复材料具有能保持创面湿润,有利于上皮细胞的生长和修复,加速伤口愈合。 目的：拟验证物理交联法制备的聚乙烯醇水凝胶的生物相容性。 设计、时间及地点：体外细胞毒性、皮内反应、迟发型超敏反应实验,2007-09/11在天津市医药科学研究所细胞实验和动物实验室完成。 材料：将医用纱布浸渍于一定浓度的聚乙烯醇溶液中,通过反复冷冻解冻制备水凝胶医用材料。 方法：参照GB/T 16886中的体外细胞毒性、皮内反应和迟发型超敏反应标准评价材料的生物相容性。 主要观察指标：①计算各组细胞的相对增殖率,确定样品的细胞毒性。②计算比较实验组与阴性组的综合平均记分。③记录样品组与阴性对照组的红斑和水肿的反应等级。 结果：细胞毒性试验中,样品浸提尿液组与50%浸提原液组的细胞相对增殖率分别为80.9%,94.1%,毒性反应均为1级;皮内反应试验中综合平均记分之差为0.2,于棉籽油介质中的综合平均记分之差为0.7;迟发型超敏反应试验中,样品浸提液致敏反应记分未超出阴性对照组。 结论：体外细胞毒性、皮内反应和迟发型超敏反应测试结果均达到国标要求,聚乙烯醇水凝胶具有可靠的生物安全性。     

Enhanced Glucose Sensor Linearity Using Poly(Vinyl Alcohol) Hydrogels

Background

High linearities, sensitivities, and low oxygen dependence constitute prime requisites for electrochemical glucose sensors. However, for implantable sensors the need to control tissue inflammation requires the use outer membranes that permit inward analyte diffusion while continuously releasing anti-inflammatory drugs and other tissue response-modifying (TRM) agents. We have shown previously that while outer membranes based on layer-by-layer (LBL) assembly enhance linearity, poly(vinyl alcohol)(PVA) hydrogels loaded with TRM-containing microspheres enable a significant reduction in tissue inflammation. This article discusses amperometric performance of glucose sensors coated with stacked LBL/PVA hydrogel outer membranes.

Methods

Sensors were fabricated by immobilizing glucose oxidase enzyme on a 50-μm platinum wire followed by deposition of stacked LBL/PVA hydrogel outer membranes. The sensor response to various glucose concentrations was determined by applying 0.7 V vs an Ag/AgCl reference electrode in phosphate-buffered saline (37°C). Michaelis–Menten analysis was performed to quantify sensor performance in terms of linearity (Km,gluapp) and oxygen dependence (Km,O2app/[Glucose]).

Results

When overlaid onto LBL-assembled outer membranes, PVA hydrogels improved sensor linearity by 60% from 10 to 16 mM of glucose and resulted in a twofold decrease in oxygen dependence.

Conclusions

Enhancement in the performance of a PVA-coated sensor is attributed to the oxygen-storing capability of PVA hydrogel due to the formation of hydrophobic domains during its freezing and thawing employed to physical cross-link the PVA. Such membranes with the capability to release TRMs continuously while storing oxygen constitute a major improvement over current outer membrane technologies.     

Combining mechanical foaming and thermally induced phase separation to generate chitosan scaffolds for soft tissue engineering

In this paper, a novel foaming methodology consisting of turbulent mixing and thermally induced phase separation (TIPS) was used to generate scaffolds for tissue engineering. Air bubbles were mechanically introduced into a chitosan solution which forms the continuous polymer/liquid phase in the foam created. The air bubbles entrained in the foam act as a template for the macroporous architecture of the final scaffolds. Wet foams were crosslinked via glutaraldehyde and frozen at ?20 °C to induce TIPS in order to limit film drainage, bubble coalescence and Ostwald ripening. The effects of production parameters, including mixing speed, surfactant concentration and chitosan concentration, on foaming are explored. Using this method, hydrogel scaffolds were successfully produced with up to 80% porosity, average pore sizes of 120 μm and readily tuneable compressive modulus in the range of 2.6 to 25 kPa relevant to soft tissue engineering applications. These scaffolds supported 3T3 fibroblast cell proliferation and penetration and therefore show significant potential for application in soft tissue engineering.     

超选择性插管栓塞治疗子宫肌瘤

目的研究和探讨子宫动脉栓塞术（UAE）治疗妇科子宫肌瘤的临床疗效。方法选择32例子宫肌瘤患者,采用Seldinger技术行单侧股动脉穿刺插管,选用管径为4—5F的Cobra导管行髂内动脉造影,根据血管造影检查结果,进一步超选择插管达双侧子宫动脉,经血管造影证实后,用携带有抗生素的PVA颗粒和明胶海绵颗粒栓塞该处血管。结果血管造影检查发现,子宫动脉是子宫肌瘤的主要供血动脉,且血管迂曲扩张,血液供应丰富。经子宫动脉栓塞治疗6～12个月后,子宫肌瘤患者的症状明显改善,月经量明显减少。子宫肌瘤体积明显缩小。术后患者有不同程度的下腹胀痛、低热,经对症处理后症状逐渐消失。结论超选择性插管栓塞治疗子宫肌瘤可有效地缩小子宫肌瘤体积,并明显改善子宫肌瘤患者的临床症状。     

PVA-PFSA/PAN渗透汽化膜强化乙酸乙酯酯化脱水及工艺过程模拟

以聚丙烯腈（PAN）中空纤维超滤膜为底膜,以酒石酸（Tac）为交联剂,制备了聚乙烯醇（PVA）与全氟磺酸（PFSA）共混复合膜,并用于乙酸乙酯-水、乙酸乙酯-乙醇-水溶液的脱水研究。考察了分离乙酸乙酯水二元溶液时,料液温度和含水量对复合膜分离性能的影响;40 ℃下分离含水2%（质量分数,下同）的乙酸乙酯水溶液时,其总渗透通量81.1 g/(m2·h),分离因子为1890;考察了复合膜用于分离乙酸乙酯乙醇水(质量比90∶2∶8)三元溶液时,料液温度的影响及脱水效果。结果表明：40 ℃时复合膜对三元溶液的总渗透通量可达251.0 g/(m2·h),此温度下,只需12 h就可将含8%初始水的三元溶液脱水至4.66%。PVA-PFSA/PAN渗透汽化膜对乙酸乙酯体系的脱水效果良好,可应用于强化乙酸乙酯酯化生产工艺。利用Aspen Plus 11.1软件对工艺流程进行了模拟,结果表明：在同等操作条件下,渗透汽化膜强化酯化工艺流程相对于普通的反应精馏,提高了乙酸乙酯的单程收率和原料的转化率,简化了乙酸乙酯生产流程。     

经支气管动脉PVA化疗栓塞治疗中央型肺癌

目的 探讨应用聚乙烯醇（PVA）颗粒行支气管动脉化疗栓塞治疗中央型肺癌的临床价值。方法 32例中央型肺癌患者，行选择性支气管动脉造影并确认病变血供，超选择下行支气管动脉干或支气管动脉分支化疗栓塞术，栓塞物质为直径350～500μm的PVA颗粒。结果 治疗总有效率100％，其中显效率84％。随访12个月，无一例患者死亡。结论 支气管动脉PVA化疗栓塞治疗中央型肺癌是一种安全、有效的方法，近期疗效肯定。