Microspheres of essential oil in polylactic acid and poly(methyl methacrylate) matrices and their blends

This study is focussed on micro-encapsulation of essential oils in polylactic acid (PLA) and a poly(methyl methacrylate) (PMMA) matrix as well as blends of the same. Microspheres were prepared by the solvent evaporation technique and characterised by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infra-red spectroscopy (FTIR). The encapsulation efficiencies and release profiles of the essential oils were studied by gas chromatography mass spectrometry (GC-MS) and head-space solid-phase microextraction GC-MS, respectively. Furthermore, the microspheres were tested for antibacterial activity against both Gram-negative and Gram-positive bacterial strains.

The results showed that the microspheres compositions (PLA/PMMA ratio) have significant effect on their characteristics. The process adopted for preparing the microspheres promoted formation of spherical particles at the sizes of 1.5–9.5?µm. The highest encapsulation efficiency of the prepared microspheres was observed in systems consisting of linalool (81.10?±?10.0?wt. % for PLA system and 76.0?±?3.3?wt. % for PMMA system). Confirmation was also made that the release rate of the microspheres was affected by the size of the same.     

角膜电刺激对糖尿病大鼠前部缺血性视神经病变模型的影响

观察并评估角膜电刺激对糖尿病大鼠前部缺血性视神经病变（AION）模型的影响。方法：实验 研究。健康雄性Sparague-Dawley大鼠40只，随机分组后抽出8只作为正常大鼠组。余下32只先予 以链脲佐菌素腹腔注射建立糖尿病大鼠模型，将造模成功的大鼠随机抽出8只作为糖尿病组，余下 24只糖尿病大鼠采用孟加拉玫瑰红联合532 nm激光方法建立AION大鼠模型。将24只造模成功的 AION大鼠随机分成3组，每组8只，分别为AION模型组，不予任何处理；电刺激组，予以角膜电刺 激（刺激参数为：电流1 mA，频率20 Hz，波宽1 ms/phase，刺激时间1 h，隔日1次，刺激2周）；假电 刺激组，电极安放位置与电刺激组相同，仅不接通电源。2周后5组大鼠进行眼底照相、光学相干断 层扫描和视觉诱发电位，然后处死，行视网膜及视神经冰冻切片，苏木精伊红染色观察。数据采用 单因素方差分析和LSD-t检验进行分析。结果：正常大鼠组视盘上半部视网膜厚度为（211±13）μm， 糖尿病大鼠组为（206±16）μm，AION模型组为（240±54）μm，假电刺激组为（216±11）μm，电刺 激组为（198±4）μm，5组视盘上半部视网膜厚度差异有统计学意义（F=2.854，P=0.038）。其中AION 模型组视盘上半部视网膜厚度高于正常组、糖尿病组、电刺激组，差异均有统计学意义（P<0.05）； 正常组与糖尿病组差异无统计学意义，AION模型组与假电刺激组未见明显差异。视觉诱发电位示 AION模型组N1潜伏期较电刺激组延长，差异有统计学意义（t=4.1，P<0.001）；AION模型组P1潜伏 期较正常组、糖尿病组、假电刺激组、电刺激组延长，差异均有统计学意义（t=4.1、2.5、2.6、3.2， P<0.05）；电刺激组N1-P1波幅大于假电刺激组，差异有统计学意义（t=4.0，P<0.001）。结论：角膜电 刺激能促进糖尿病大鼠前部缺血性视神经病变模型肿胀的视盘变薄，加速视盘水肿的消退，同时在 一定程度上改善视功能。     

How structural and functional MRI can inform dual-site tACS parameters: A case study in a clinical population and its pragmatic implications

BackgroundAbnormalities in frontoparietal network (FPN) were observed in many neuropsychiatric diseases including substance use disorders. A growing number of studies are using dual-site-tACS with frontoparietal synchronization to engage this network. However, a computational pathway to inform and optimize parameter space for frontoparietal synchronization is still lacking. In this case study, in a group of participants with methamphetamine use disorders, we proposed a computational pathway to extract optimal electrode montage while accounting for stimulation intensity using structural and functional MRI.MethodsSixty methamphetamine users completed an fMRI drug cue-reactivity task. Four main steps were taken to define electrode montage and adjust stimulation intensity using 4x1 high-definition (HD) electrodes for a dual-site-tACS; (1) Frontal seed was defined based on the maximum electric fields (EF) predicted by simulation of HD montage over DLPFC (F3/F4 in EEG 10–10), (2) frontal seed-to-whole brain context-dependent correlation was calculated to determine connected regions to frontal seeds, (3) center of connected cluster in parietal cortex was selected as a location for placing the second set of HD electrodes to shape the informed montage, (4) individualized head models were used to determine optimal stimulation intensity considering underlying brain structure. The informed montage was compared to montages with large electrodes and classic frontoparietal HD montages (F3-P3/F4-P4) in terms of tACS-induced EF and ROI-to-ROI task-based/resting-state connectivity.ResultsCompared to the large electrodes, HD frontoparietal montages allow for a finer control of the spatial peak fields in the main nodes of the FPN at the cost of lower maximum EF (large-pad/HD: max EF[V/m] = 0.37/0.11, number of cortical sub-regions that EF exceeds 50% of the max = 77/13). For defining stimulation targets based on EF patterns, using group-level head models compared to a single standard head model results in comparable but significantly different seed locations (6.43 mm Euclidean distance between the locations of the frontal maximum EF in standard-space). As expected, significant task-based/resting-state connections were only found between frontal-parietal locations in the informed montage. Cue-induced craving score was correlated with frontoparietal connectivity only in the informed montage (r = ?0.24). Stimulation intensity in the informed montage, and not in the classic HD montage, needs 40% reduction in the parietal site to reduce the disparity in EF between stimulation sites.ConclusionThis study provides some empirical insights to montage and dose selection in dual-site-tACS using individual brain structures and functions and proposes a computational pathway to use head models and functional MRI to define (1) optimum electrode montage for targeting FPN in a context of interest (drug-cue-reactivity) and (2) proper transcranial stimulation intensity.     

辛味中药在治疗消渴证中的应用价值及中药五味理论现代研究的思考

辛味是中药五味学说中的重要性味之一,通常具有“发散”“行气”和“行血”的作用,且辛味中药在传统医学临床应用中占有较大比例。结合中药辛味的功效内涵及传统中医理论对消渴证的认识,阐述辛味中药与消渴证治疗之间的内在联系,总结辛味中药对“消渴三消”的治疗意义与价值。并在此基础上,对中药五味理论的现代研究趋势和发展方向进行思考,为同行研究提供参考。     

Exploration of D022-Type Al3TM(TM = Sc,Ti, V,Zr, Nb,Hf, Ta): Elastic Anisotropy,Electronic Structures,Work Function and Experimental Design

The structural properties, elastic anisotropy, electronic structures and work function of D0₂₂-type Al₃TM (TM = Sc, Ti, V, Y, Zr, Nb, La, Hf, Ta) are studied using the first-principles calculations. The results indicate that the obtained formation enthalpy and cohesive energy of these compounds are in accordance with the other calculated values. It is found that the Al₃Zr is the most thermodynamic stable compound. The mechanical property indexes, such as elastic constants, bulk modulus, shear modulus, Young’s modulus, Poisson’s ratio, and Vickers hardness are systematically explored. Moreover, the calculated universal anisotropic index, percent anisotropy and shear anisotropic factors of D0₂₂-type Al₃TM are analyzed carefully. It demonstrates that the shear modulus anisotropy of Al₃La is the strongest, while that of Al₃Ta is the weakest. In particular, the density of states at Fermi level is not zero, suggesting that these phases have metal properties and electrical conductivity. More importantly, the mechanisms of correlation between hardness and Young’s modulus are further explained by the work function. Finally, the experimental design proves that D0₂₂-Al₃Ta has an excellent strengthening effect.     

经皮电刺激联合导乐镇痛对分娩结局的影响及安全性分析

目的 探讨经皮电刺激联合导乐分娩镇痛对分娩结局的影响及安全性。方法 选择160例在我院住院待产的产妇作为研究对象,随机将其分为观察组与对照组,每组各80例;其中对照组予导乐分娩镇痛,观察组给予经皮电刺激联合导乐分娩镇痛。观察比较两组的VAS评分、产程时间、产后出血、剖宫产率、产妇满意度、新生儿情况、不良反应发生情况等。结果 与镇痛前比较,观察组镇痛后各时间段VAS评分降低,P＜0.05;与对照组比较,观察组的产后2 h出血量、剖宫产率降低,产妇满意度提高,P＜0.05。结论 经皮电刺激联合导乐镇痛可减轻产妇痛苦,降低剖宫产率,减少产后出血,提高产妇满意度,且无明显不良反应,值得在临床上推广应用。