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.     

理气中药组方对糖尿病大鼠胃排空延迟的作用

目的:观察理气中药经验组方对糖尿病大鼠胃排空延迟的干预作用。方法:雌雄各半成年SD大鼠110只,随机分为正常组(A组)、糖尿病中药组(B组)、糖尿病胃复安组(C组)、糖尿病组(D组)。A组、D组1次/d按10 mL/只予0.9%生理盐水灌胃,B组1次/d按8 mL/只予中药煎剂灌胃,C组1次/d按0.5 mg/只予胃复安片灌胃。喂养12周后,行13C胃排空实验及甲基橙水溶液胃排空实验,观察各组大鼠胃排空情况。结果:糖尿病大鼠胃排空较正常大鼠明显延迟(P0.01),糖尿病大鼠胃排空延迟模型制作成功。糖尿病中药组和糖尿病胃复安组大鼠胃排空较糖尿病组快(P0.01);糖尿病中药组大鼠胃排空较糖尿病胃复安组大鼠快(P0.05)。结论:常规喂养12周后糖尿病大鼠出现胃排空延迟。理气中药陈皮、枳实、木香、香附组方煎剂和胃复安均能促进糖尿病大鼠胃排空,理气中药组方煎剂的效果优于胃复安。     

Poly(ortho ester) nanoparticles targeted for chronic intraocular diseases: ocular safety and localization after intravitreal injection

Treatment of posterior eye diseases is more challenging than the anterior segment ailments due to a series of anatomical barriers and physiological constraints confronted by drug delivery to the back of the eye. In recent years, concerted efforts in drug delivery have been made to prolong the residence time of drugs injected in the vitreous humor of the eye. Our previous studies demonstrated that poly(ortho ester) (POE) nanoparticles were biodegradable/biocompatible and were capable of long-term sustained release. The objective of the present study was to investigate the safety and localization of POE nanoparticles in New Zealand white rabbits and C57BL/6 mice after intravitreal administration for the treatment of chronic posterior ocular diseases. Two concentration levels of POE nanoparticles solution were chosen for intravitreal injection: 1.5?mg/ml and 10?mg/ml. Our results demonstrate that POE nanoparticles were distributed throughout the vitreous cavity by optical coherence tomography (OCT) examination 14 days post-intravitreal injection. Intraocular pressure was not changed from baseline. Inflammatory or adverse effects were undetectable by slit lamp biomicroscopy. Furthermore, we demonstrate that POE nanoparticles have negligible toxicity assessed at the cellular level evidenced by a lack of glia activation or apoptosis estimation after intravitreal injection. Collectively, POE nanoparticles are a novel and nontoxic as an ocular drug delivery system for the treatment of posterior ocular diseases.     

Glutamate hypothesis in schizophrenia

Schizophrenia is a chronic and severe psychiatric disorder that has profound impact on an individual’s life and on society. Thus, developing more effective therapeutic interventions is essential. Over the past quarter‐century, an abundance of evidence from pharmacologic challenges, post‐mortem studies, brain imaging, and genetic studies supports the role of glutamatergic dysregulation in the pathophysiology of schizophrenia, and the results of recent randomized clinical trials based on this evidence have yielded promising results. In this article, we review the evidence that alterations in glutamatergic neurotransmission, especially focusing on the N‐methyl‐d ‐aspartate receptor (NMDAR) function, may be a critical causative feature of schizophrenia, how this contributes to pathologic circuit function in the brain, and how these insights are revealing whole new avenues for treatment development that could reduce treatment‐resistant symptoms, which account for persistent disability.     

顶空气相色谱-质谱法测定布南色林原料药中遗传毒性杂质

目的：建立顶空气相色谱-质谱法测定布南色林原料药中甲磺酸甲酯、甲磺酸乙酯和甲磺酸异丙酯3种遗传毒性杂质含量的方法。方法：采用顶空气相色谱-质谱法，以甲磺酸丁酯为内标，按内标标准曲线法进行甲磺酸甲酯、甲磺酸乙酯和甲磺酸异丙酯的含量测定。色谱条件：DB-WAX毛细管色谱柱（30 m×0.25 mm×0.25 μm）；程序升温，初始柱温为40℃，维持3 min，升温速率为30℃·min^-1，终止温度150℃，保持2 min；进样口温度为110℃；载气（He）流速为0.6 mL·min^-1；进样量为1 mL；进样方式为分流进样，分流比为20：1。质谱条件：电子轰击离子源（EI），扫描方式为选择性离子检测；离子源温度为200℃；接口温度为150℃；电子能量为70 eV；溶剂延迟1 min。结果：3种杂质成分之间的分离度均大于2.0；甲磺酸甲酯、甲磺酸乙酯、甲磺酸异丙酯检测质量浓度线性范围均为0.025~3.0 μg·mL^-1（r ≥ 0.998 5）；精密度、稳定性、重复性试验的RSD<5%；加样回收率分别为93.40%~101.40%（RSD为3.2%，n=9）、92.80%~99.70%（RSD为2.5%，n=9）和96.30%~100.75%（RSD为1.6%，n=9）。结论：该方法简便、准确、灵敏、迅速，可用于布南色林原料药中3种遗传毒性杂质的测定。     

Caffeic acid phenethyl ester,a propolis polyphenolic,attenuates potentially cadmium-induced testicular dysfunction in mice

Abstract

Cadmium (Cd) as environmental pollutant can induce severe damage, particularly to the testis. This study investigated the effects of Caffeic acid phenethyl ester (CAPE) on testicular dysfunction induced by Cd. Adult mice were intraperitoneally injected with cadmium chloride (CdCl₂) with different doses of CAPE pretreatment. After CdCl₂ injection, body/testis weight ratio decreased, Cd levels accumulated and zinc levels decreased in testis. Furthermore, Cd intoxication caused a significant increase of oxidative stress levels, antioxidant enzymes activities, and glutathione levels. Interestingly, significant improvements were observed after the administration of CAPE. Our results demonstrated the protective effect of CAPE, linking Cd testicular dysfunction to oxidative stress.     

l-DOPA induces concentration-dependent facilitation and inhibition of presynaptic acetylcholine release in the guinea-pig submucous plexus

Neurotransmitter- or neuromodulator-like actions ofl-DOPA were investigated with intracellular recordings from submucous plexus neurons of the guinea-pig caecum.l-DOPA at 30 nM augmented the amplitude of fast EPSPs, but did not affect depolarizations elicited by puff application of acetylcholine (ACh). The augmenting effect ofl-DOPA on the fast EPSPs was counteracted byl-DOPA methyl ester. The fast EPSPs were depressed by 10 μMl-DOPA, but transiently augmented after rinsing the drug.l-DOPA methyl ester did not affect the inhibitory action ofl-DOPA on the fast EPSPs, but antagonized the potentiation following the inhibition. The depolarization elicited by exogenously applied. ACh was inhibited by 10 μMl-DOPA. Intracellular Ca²⁺ concentrations ([Ca²⁺]_i) of the neuronal soma were measured with fura-2 microfluorophotometry. The transient increase in the [Ca²⁺]_i evoked by the somatic action potential (Δ[Ca²⁺]_AP) was facilitated by 30 nMl-DOPA, but decreased by the drug at 10 μM. It is concluded thatl-DOPA at low concentrations enhances the Δ[Ca²⁺]_AP, increasing the neurotransmitter release, but at high dose diminishes the Δ[Ca²⁺]_AP, inhibiting the neurotransmission.     

汽油添加剂甲基叔丁基醚的毒性研究

目的　通过研究汽油添加剂甲基叔丁基醚 (MTBE)对小鼠体内谷胱甘肽 (GSH)、谷胱甘肽过氧化物酶 (GSH -Px)活性的改变以及骨髓微核、精子畸变率的影响 ,了解汽油添加剂甲基叔丁基醚的毒性。方法　 40只健康昆明种成年小鼠 ,体重 3 3 .3± 6 .9g ,随机分为 4组。灌胃染毒 ,染毒剂量分别为1 6 0 0、40 0、1 0 0和 0mg kg。每天 1次 ,每周 5天 ,共计 40天。结果　MTBE染毒各组小鼠体重轻度降低 ,染毒组全血及肝组织匀浆中GSH在低剂量染毒时增高 ,而高剂量时表现为降低 ,与对照组比较差异有显著性 (P <0 .0 5 ) ;GSH -Px活性明显减低 ,染毒高剂量组与对照组比较差异有高度显著性 (P <0 .0 1 ) ;骨髓嗜多染红细胞微核及精子畸变率增高 ,与对照组比较明显增高 ,差异有显著性 (P <0 .0 5 )。结论　MTBE对昆明小鼠具有一定毒性 ,可降低全血及肝脏组织中GSH -Px活性 ,低剂量时可增加全血及肝脏组织中GSH含量 ,而高剂量可降低其含量。MTBE能使骨髓微核率、精子畸形率明显增高 ,提示MTBE具有潜在的遗传毒性。     

L—NAME促进大鼠红藻氨酸诱导性发作

为证明癫痫发作早期一氧化氮（ＮＯ）抗发作效应，用ＮＯ合酶（ＮＯＳ）抑制剂Ｌ－硝基精氨酸甲酯（Ｌ－ＮＡＭＥ）对大鼠红藻氨酸（ＫＡ）诱导性发作进行干预，同时用分光光度法检测海马结构中ＮＯＳ活性的早期变化。发现ＫＡ发作１０ｍｉｎ、３０ｍｉｎ组海马结构中ＮＯＳ活性明显升高，而ＫＡ注射前３０ｍｉｎ给予Ｌ－ＮＡＭＥ可显著抑制ＮＯＳ活性的升高，这种抑制效应与大鼠ＫＡ发作中湿狗样摇动（ＷＤＳ）的提早出现和发生次数增多显著相关。结果提示在ＫＡ诱导大鼠发作早期内源性ＮＯ具有明显的抗发作效用。     

薄层扫描法测定复脉定冲剂中远志有效成分的含量

采用薄层扫描法对复脉定冲剂中远志有效成分３，４，５－三甲氧基反式肉桂酸乙酯的含量进行测定。方法简单、快速，结果可靠，可作为该制剂的质控标准。