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.     

Impact of different types of olive oil on cardiovascular risk factors: A systematic review and network meta-analysis

Background and aimThis network meta-analysis (NMA) compares the effects of different types of olive oil (OO) on cardiovascular risk factors.Methods and resultsLiterature search was conducted on three electronic databases (Medline, Web of Science, and Cochrane Central). Inclusion criteria: Randomized controlled trials (RCTs) (≥3 weeks duration of intervention) comparing at least two of the following types of OO: refined OO (ROO), mixed OO (MOO), low phenolic (extra) virgin OO (LP(E)VOO), and high phenolic (extra) virgin OO (HP(E)VOO). Random-effects NMA was performed for seven outcomes; and surface under the cumulative ranking curve (SUCRA) was estimated, using an analytical approach (P-score). Thirteen RCTs (16 reports) with 611 mainly healthy participants (mean age: 26–70 years) were identified. No differences for total cholesterol, HDL-cholesterol, triacylglycerols, and diastolic blood pressure were observed comparing ROO, MOO, LP(E)VOO and HP(E)VOO. HP(E)VOO slightly reduce LDL-cholesterol (LDL-C) compared to LP(E)VOO (mean difference [MD]: −0.14 mmol/L, 95%–CI: −0.28, −0.01). Both, HP(E)VOO and LP(E)VOO reduces SBP compared to ROO (range of MD: −2.99 to −2.87 mmHg), and HP(E)VOO may improve oxidized LDL-cholesterol (oxLDL-C) compared to ROO (standardized MD: −0.68, 95%–CI: −1.31, −0.04). In secondary analyses, EVOO may reduce oxLDL-C compared to ROO, and a dose-response relationship between higher intakes of phenolic compounds from OO and lower SBP and oxLDL-C values was detected. HP(E)VOO was ranked as best treatment for LDL-C (P-score: 0.83), oxLDL-C (0.88), and SBP (0.75).ConclusionsHP(E)VOO may improve some cardiovascular risk factors, however, public health implications are limited by overall low or moderate certainty of evidence.     

The preventive role of wheat germ oil against sertraline‐induced testicular damage in male albino rats

Sertraline is an antidepressant medication used extensively in the therapy of depression. The present investigation was intended to estimate the actual protective role of wheat germ oil on sertraline‐caused testicular injury in albino rats. Sertraline (human therapeutic dose, 15.63 mg/kg) was orally administrated to rats for 28 successive days. Sertraline‐administered rats were concurrently supplemented with wheat germ oil (human therapeutic dose, 68.75 mg/kg) for 28 successive days. Sertraline administration induced an elevation in testicular DNA damage and acute testicular damage illustrated by the histopathological alterations including marked degeneration and necrosis of germ cells lining seminiferous tubules, as well as interstitial oedema, congestion of interstitial blood vessel. Wheat germ oil administration potentially mitigated the histopathological alterations of sertraline‐administered rats. Lipid peroxidation, oxidative stress biomarker, showed a significant elevation in testicular tissue of sertraline‐administered rats. Furthermore, glutathione content and catalase activity were decreased in testicular tissue of sertraline‐administered rats. Serum testosterone level was elevated in sertraline‐administered rats. Wheat germ oil significantly reduced lipid peroxidation of testicular tissue and improved the antioxidant defences. Finally, wheat germ oil has a preventive role against testicular damage induced by sertraline in rats probably via its potential to prevent reactive oxygen species.     

多巴胺受体与其他血压调节系统的交互作用在高血压研究中的地位

肾脏是人体负责钠排泄的重要器官,多巴胺由于其强大的抑制肾脏钠重吸收作用而在原发性高血压的发生、发展中发挥重要作用。多巴胺受体的5个亚型均直接或间接通过与其他血压调节系统的交互作用,参与肾脏钠通道或血压的调节。现就多巴胺受体在调节机体血压和肾脏利钠、利尿作用中所发挥的重要作用作一综述。     

棕榈油对成人血脂和血小板功能的影响

报道了棕榈油（ＰＡ），花生油（ＰＥ）对血清总胆固醇水平（ＴＣ）在５．５～７．０ｍｍｏｌ／Ｌ的受试者血脂和血小板功能的影响。５１名受试者（男３１人，女２０人，年龄３０～６６岁之间）分为两组，一组男１５人，女１１人，称ＰＥ组；另一组男１６人女９人，称ＰＡ组，预备期３周，膳食以当地日常食用的花生油烹调，实验期６周。ＰＡ组受试者食用以棕榈油烹调的实验膳；ＰＥ组受试者仍食花生油烹调的膳食。脂肪约占膳食能量的３０％，其中６０％～６５％来自实验油。实验结果表明：与起始值相比，６周末ＰＡ组受试者血清ＴＣ，低密度脂蛋白胆固醇（ＬＤＬ－Ｃ）和总胆固醇与高密度脂蛋白胆固醇比值（ＴＣ／ＨＤＬ－Ｃ）显著下降，血浆血栓素Ｂ２（ＴＸＢ２）／６－酮前列环素Ｆ１α、（６－ｋｅｔｏ－ＰＧＦ１α）比值显著下降，全血血小板聚集率未见显著变化。ＰＥ组受试者的血脂、血浆ＴＸＢ２、６－ｋｅｔｏ－ＰＧＦ１α及全血血小板聚集率等指标均未出现显著变化。提示，棕榈油作为我国居民家庭烹调用油并不会增加发生心血管疾病的危险。     

尼罗罗非鱼肉营养成分分析

<正> 尼罗罗非鱼(Tilapia nilotica)是我国从非洲引进的热带鱼类,具有刺少肉味鲜嫩、食性广、生长快、繁殖力强、养殖周期短等特点。已快速地养殖到全国各地。作者对利用地热资源人工喂养条件下的尼罗罗非鱼肉的氨基酸和肉内的粗蛋白、脂肪、维生素等成分进行分析,评估尼罗罗非鱼肉的营养价值,从营养学的角度为人们提供科学依据。     

烹调油烟致大小鼠肺癌的实验研究

[目的]了解烹调油烟（cooking oil fumes，COF）的动物致癌性。[方法]采用动式染毒法给Balb／c小鼠（雌雄各半）吸入COF浓度为9．09、20．65、38．85mg／m^3，染毒1次／1～2d，30min／次，共150次，计8个月；SD大鼠（雌雄各半）吸入COF浓度为6、88、15．06、35．33mg／m^3，染毒1次／2d，30min／次，共191次，计12．5个月。分别制备COF慢性中毒动物模型；两实验均设空白对照组，吸入与实验组相同温度的清洁空气。[结果]COF诱发Balb／c小鼠实验组肺癌总发生率为18、95％（29／153），低、中、高浓度组肺癌发生率分别为15．09％、20、00％和22．00％，与对照组差异均有显著性。但低、中、高三组间差异无显著性（P〉0．05）；COF诱发SD大鼠肺癌总发生率为9、10％（9／99），低、中、高浓度组肺癌发生率分别为6．45％、8．57％、12．12％，高浓度组肺癌发生率高于对照组（P〈0．05）。各性别组间肺癌发生率的差别无显著性（P〉0．05）。[结论]COF可以诱导Balb／c小鼠和SD大鼠肺癌，诱发的肺癌主要为肺腺癌（小鼠28／29，大鼠7／9），余为小细胞肺癌。