二十八烷醇抗大鼠心肌线粒体损伤的研究

目的　采用乳化二十八烷醇饲育Wistar大鼠 ,研究二十八烷醇对力竭运动大鼠心肌线粒体脂质过氧化、抗氧化系统及Ca2 + 浓度的影响。方法　Wistar大鼠随机分成三组 ,即 :安静对照组、运动力竭组、运动力竭加二十八烷醇组 ,每组 12只 ,实验期 3W ,建立力竭运动模型 ,测定心肌线粒体中丙二醛 (MDA)、谷胱甘肽过氧化物酶(GSH -Px)和超氧化物歧化酶 (SOD)活性、Ca2 + 浓度。结果　二十八烷醇能够 :降低力竭运动大鼠心肌线粒体中MDA的含量 (P <0 0 5 ) ;提高力竭运动大鼠心肌线粒体SOD和GSH -Px的活性 (P <0 0 1,P <0 0 5 ) ;保持力竭运动大鼠心肌线粒体Ca2 + 浓度。结论　二十八烷醇可减少力竭运动后因脂质过氧化而产生过多的自由基 ,降低自由基对心肌线粒体的损伤 ,维持细胞膜的功能 ,说明二十八烷醇有保护心肌线粒体的功能和防止心肌损伤的作用。     

硒化乳酸菌胞外多糖对小鼠腹腔巨噬细胞及肿瘤细胞内游离Ca~(2+)的影响

目的:研究硒化乳酸菌胞外多糖对小鼠腹腔巨噬细胞、SGC7901胃癌细胞及海拉细胞(Hela cells)内游离Ca2+的影响。方法:分离制备小鼠腹腔巨噬细胞,利用Ca2+荧光探针Fluo-3/AM及激光共聚显微镜测定加药后10 min细胞内Ca2+浓度的变化。结果:添加硒化多糖后,巨噬细胞内Ca2+浓度缓慢升高,而胃癌细胞与Hela细胞内Ca2+水平均有不同程度的下降。结论:通过对乳酸菌胞外多糖进行硒化修饰可增强其刺激巨噬细胞的能力,因而发挥其免疫功效。硒化多糖与肿瘤细胞表面受体结合后引起细胞内Ca2+内流的减少,提示硒化后的多糖可引起肿瘤细胞不同程度的细胞凋亡。     

姜黄素对过度训练所致大鼠心肌细胞凋亡的保护作用

目的:研究姜黄素缓解过度训练所致的氧化应激,抑制大鼠心肌细胞凋亡的保护作用。方法:60只7周龄SPF级雄性Wistar大鼠经适应性饲养及训练后随机分为对照组(C组,12只)、过度训练组(OM组,24只)、姜黄素+过度训练组(COM组,24只)。C组不进行任何训练,OM组、COM组大鼠进行8周递增负荷游泳训练。训练期间,COM组以200 mg/(kg·d)剂量姜黄素进行灌胃,灌胃体积5 mL/kg,其余两组灌胃等体积0.5%羧甲基纤维素纳。末次训练后24 h,光镜观察心肌组织病理学改变,检测血清睾酮(T)、皮质酮(Cor)、心肌肌钙蛋白I(cTnI)浓度,以及心肌组织凋亡水平和核因子E2相关因子2(Nrf2)、血红素加氧酶-1(HO-1)、B淋巴细胞瘤因子-2(Bcl-2)、Bcl-2相关X蛋白(Bax)表达,同时测定心肌组织总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)活性以及丙二醛(MDA)浓度。结果:8周递增负荷游泳训练后,光镜下C组大鼠心肌组织结构正常;OM组出现组织病理学改变;COM组较OM组明显减轻。与C组比较,OM组血清Cor、cTnI、心肌细胞凋亡水平和促凋亡蛋白Bax表达水平及心肌MDA浓度均升高(p<0.01),血清T水平、心肌T-AOC和SOD活性(p<0.01)、心肌HO-1及抗凋亡蛋白Bcl-2表达水平(p<0.05)降低;心肌Nrf2表达水平无显著变化(p>0.05)。与OM组比较,COM组血清Cor、心肌细胞凋亡水平、Bax表达水平(p<0.01)和血清cTnI水平、心肌MDA浓度(p<0.05)降低,血清T水平、心肌Nrf2和Bcl-2表达水平、心肌T-AOC和SOD活性(p<0.01)、心肌HO-1(p<0.05)升高。组间T/Cor比值变化趋势与T变化相一致,Bcl-2/Bax比值变化趋势与Bcl-2变化相一致。结论:姜黄素通过上调Nrf2、HO-1蛋白表达,有效缓解过度训练引发的氧化应激,从而增加Bcl-2表达,减少Bax表达,抑制大鼠心肌细胞凋亡,保护心脏组织结构和功能正常。     

硒化乳酸菌胞外多糖对小鼠腹腔巨噬细胞及肿瘤细胞内游离Ca2+的影响

目的：研究硒化乳酸菌胞外多糖对小鼠腹腔巨噬细胞、SGC7901胃癌细胞及海拉细胞（Hela cells）内游离Ca2+的影响。方法：分离制备小鼠腹腔巨噬细胞,利用Ca2+荧光探针Fluo-3/AM及激光共聚显微镜测定加药后10 min细胞内Ca2+浓度的变化。结果：添加硒化多糖后,巨噬细胞内Ca2+浓度缓慢升高,而胃癌细胞与Hela细胞内Ca2+水平均有不同程度的下降。结论：通过对乳酸菌胞外多糖进行硒化修饰可增强其刺激巨噬细胞的能力,因而发挥其免疫功效。硒化多糖与肿瘤细胞表面受体结合后引起细胞内Ca2+内流的减少,提示硒化后的多糖可引起肿瘤细胞不同程
度的细胞凋亡。     

氧化初期金属离子强度对动物体脂氧化的影响效果

研究了不同浓度金属离子(Fe2+、Ca2+、Cu2+、Mg2+)对牦牛体脂硫代巴比妥酸反应产物(TBARS)的影响效果。经0.1mol/LCu2+处理后的动物体脂TBARS在第25d超过0.5mg/kg,显著提高氧化程度(p<0.05),该浓度可作为抑制氧化的参考浓度。1mol/LFe2+处理下TBARS较其他各组明显降低(p<0.05),0.05mol/L处理组能较大程度上促进氧化过程。各浓度Mg2+处理后的TBARS呈逐步上升趋势,但变化趋势总体弱于Fe2+。不同浓度Ca2+对氧化初期TBARS的变化影响较为一致,且与空白组相差不大(p>0.05)。结论为动物体脂储藏和加工选用恰当的金属螯合剂和复配抗氧化剂含量提供参考。     

黑灵芝多糖对S-180荷瘤小鼠腹腔巨噬细胞cAMP/PKA、IP_3/Ca~(2+)及DAG/PKC信号通路的影响

目的:探讨黑灵芝多糖(polysaccharide from Ganoderma atrum,PSG-1)对S-180荷瘤小鼠腹腔巨噬细胞环磷酸腺苷(cyclic adenosine monophosphate,cAMP)/细胞蛋白激酶A(protein kinase A,PKA)、三磷酸肌醇(inositol triphosphate,IP3)/Ca2+及甘油二酯(diacylglycerol,DAG)/蛋白激酶C(protein kinase C,PKC)信号通路的影响。方法:将S-180细胞接种于BALB/c小鼠体内建立荷瘤小鼠模型,成模后收集腹腔巨噬细胞进行体外培养,用不同浓度的PSG-1干预;ELISA法分别检测巨噬细胞培养上清液中的IP3、DAG和AMP含量;流式细胞仪测定细胞内Ca2+含量;Western blotting测定细胞PKA及PKC蛋白表达。结果:PSG-1在20~160μg/mL质量浓度范围能促进S-180荷瘤小鼠腹腔巨噬细胞产生cAMP、IP3和DAG,同时能增加细胞内Ca2+含量,并显著增强PKA及PKC蛋白表达量。结论:PSG-1能有效激活S-180荷瘤小鼠腹腔巨噬细胞cAMP/PKA、IP3/Ca2+及DAG/PKC信号通路。由此推测,PSG-1可能通过cAMP/PKA、IP3/Ca2+及DAG/PKC信号通路促进S-180荷瘤小鼠腹腔巨噬细胞抗肿瘤作用。     

醋蛋多肽血管紧张素转化酶抑制活性的稳定性研究

研究了温度、pH、金属离子、食盐及食品中常见糖类和防腐剂对醋蛋多肽血管紧张素转化酶(ACE)抑制活性的影响。结果表明:醋蛋多肽的ACE抑制活性对热不稳定,对pH稳定;当金属离子浓度达到5mmol/L时,醋蛋多肽的ACE抑制活性有较明显的下降,其影响大小顺序为K+>Zn2+>Cu2+>Ca2+>Mg2+;食盐能降低醋蛋多肽的ACE抑制活性;在实验浓度范围内,葡萄糖、蔗糖、乳糖、苯甲酸和山梨酸对醋蛋多肽ACE抑制活性影响不大。     

玉足海参糖胺聚糖对血液中钙离子的影响

研究玉足海参糖胺聚糖(GAG)对血液中钙离子(Ca2+)浓度的影响. 健康家兔耳缘静脉取血进行体外复钙凝血实验,考察GAG对复钙凝血时间的影响.用GAG浸泡、烘干后的毛细管进行小鼠眼眶后静脉丛取血,考察GAG对取血过程中Ca2+浓度的影响.考察静脉注射连续给药一周后,GAG对大鼠血液中Ca2+浓度的影响.GAG对复钙凝血时间的延长可随足够Ca2+的加入而减小.用GAG浸泡、烘干后的毛细血管对小鼠眼眶后静脉丛进行取血,发现GAG可显著降低血液中Ca2+的浓度.     

不同衰老程度青菜电导率和4种主要离子溶出特性研究

目的:探究不同衰老程度青菜细胞内外主要离子的分布及水中溶出特性,从而了解青菜细胞膜对离子阻隔,及细胞壁对离子吸附的特性。方法:测定常温贮藏0,3,7 d的青菜外叶在流动水中电导率和钾(K+)、钙(Ca2+)、钠(Na+)和氯(Cl-)离子浓度变化。结果 :发现水浸泡2～19 min时,贮藏3 d青菜的电导率高于7 d和0 d青菜。此后,贮藏7 d青菜的电导率显著高于3 d青菜,后者显著高于0 d青菜。青菜K+、Cl-溶出量显著高于Na+和Ca2+,其对电导率变化贡献较大。青菜中Ca2+和Na+在开始20 s迅速溶出,且衰老7 d的青菜快速溶出持续到40 s,说明细胞外K+和Ca2+浓度比细胞内显著增高。贮藏3 d青菜的Ca2+含量显著低于0 d和7 d青菜,这可能与细胞壁吸附能力变化有关。结论:测定青菜相对电导率需要流动水浸泡30～60 min。青菜细胞外Ca2+和Na+浓度显著高于细胞内,细胞内外K+和Cl-浓度差异很小。测定Cl-和K+浓度能判断细胞膜完好程度,测定Ca2+浓度能反映细胞壁成分变化。     

莲房原花青素对极低频电磁场致星形胶质细胞氧化损伤的预防作用

目的:研究极低频电磁场(extremely low frequency electromagnetic fields,ELF-EMF)对星形胶质细胞的氧化损伤及莲房原花青素(procyanidins from lotus seedpod,LSPC)的预防作用.方法:以原代培养的SD大鼠星形胶质细胞建立ELF-EMF损伤模型,检测经LSPC预处理前后的细胞生存率、星形胶质细胞内活性氧(Reactive oxygen species,ROS)、超氧化物歧化酶(Super oxide dismutase,SOD)、丙二醛(MDA)和Ca2+含量.结果:辐射模型组的细胞生存率为54.38％,极显著下降(与正常对照组相比,p＜0.01);经5、10、20μg/mL LSPC预处理后,细胞生存率分别为65.09％、75.34％和90.78％,显著上升(与辐射模型组相比,p＜0.05);ELF-EMF引起细胞内SOD活力下降,MDA、ROS和Ca2含量上升,经5、10、20μg/mL LSPC预处理,能有效阻止SOD活力下降并显著抑制MDA、ROS和Ca2+含量的上升(与辐射模型组相比,p＜ 0.05).结论:LSPC对ELF-EMF导致的星形胶质细胞氧化损伤有明显的预防作用.     

Changes in smoking prevalence in Ukraine in 2001-5

Objectives

To analyse trends in smoking prevalence in Ukraine from three surveys conducted in 2001–5, and to explore correlates of observed changes, in order to estimate the stage of tobacco epidemic in Ukraine.

Design

Repeated national interview surveys in Ukraine in 2001, 2002 and 2005.

Main outcome measure

Prevalence of current smoking among the population aged ⩾15 years.

Results

The age‐standardised prevalence of current smoking in Ukrainian men was 54.8% in 2001 and 66.8% in 2005. Among Ukrainian women, prevalence increased from 11.5% in 2001 to 20.0% in 2005. ORs for yearly increase in prevalence were estimated as 1.164 (95% CI 1.111 to 1.220) for men and 1.187 (1.124 to 1.253) for women, which implies that, on average, 3–4% of men and 1.5–2% of women living in Ukraine join the smoking population each year.

Conclusions

In Ukraine, smoking prevalence is increasing in most population groups. Among men, the medium deprivation group with secondary education has the highest smoking prevalence. Among women, while the most educated, young and those living in larger cities are the leading group for tobacco use, other groups are also increasing their tobacco use. Tobacco promotion efforts appear to have been significantly more effective in Ukraine than smoking control efforts. The decrease in real cigarette prices in Ukraine in 2001–5 could be the main factor explaining the recent growth in smoking prevalence.Ukraine is a large eastern European country with high smoking prevalence. Tobacco products are widely available at very low prices, and the transnational tobacco industry is extremely successful in promoting its products and lobbying for its interests in the legislative field. Advocacy of tobacco control has only recently achieved some success in the legislative field, with the first tobacco control law being adopted in late 2005. Ukraine ratified the Framework Convention on Tobacco Control in 2006, but there is still much cause for concern regarding the enforcement and effectiveness of the adopted legislative measures. Unfortunately, the government is not yet involved in nationwide surveillance of the tobacco problem, and the available data have mostly been gathered with funding from foreign donors. Several attempts have been made to measure the extent of the tobacco epidemic in the countries of the former Soviet Union (FSU).^{1,2,3,4,5,6,7} Most of these studies have shown rather high smoking prevalence among men (50–70%) and comparatively low prevalence among women (5–20%). Most countries in the FSU have similar smoking rates, while certain trends are shown to be related to the differences in how the transnational tobacco industry succeeds in every national tobacco market.⁶ Unfortunately, few studies have been published showing trends in smoking prevalence in the FSU.⁷ In Ukraine, two studies^3,4 provided point estimates of smoking prevalence.The aim of this study was to analyse trends in smoking prevalence in Ukraine, on the basis of three surveys conducted in 2001–5, and to explore correlates of observed changes in order to estimate the stage of the tobacco epidemic in Ukraine.     

2010年河南省部分食品中重金属污染状况分析

了解河南省部分食品中重金属污染的现状。方法 在河南省18个省辖市采集8大类3 657份食品样品,按照国家标准检测食品中铅、镉和汞的含量,检测结果按照GB 2762—2012《食品安全国家标准食品中污染物限量》进行评价。结果 河南省部分食品中铅含量的平均值为0.34 mg/kg,总体超标率为8.8%(320/3 656),其中粮食、肉类和蔬菜中超标率较高,分别为17.2%(95/552)、14.5%(85/587)和10.7%(57/534);部分食品中镉含量的平均值为0.054 mg/kg,总体超标率为3.9%(143/3 657),其中食用菌和蛋类中超标率较高,分别为9.6%(49/508)和8.1%(42/518);部分食品中汞含量的平均值为0.077 mg/kg,总体超标率为8.3%(303/3 657),其中蔬菜和粮食中超标率较高,分别为25.3%(135/534)和12.3%(68/551)。结论 河南省部分食品中铅、汞污染情况较为严重,其中粮食、蔬菜和肉类食品中污染情况尤为突出,需要加强监管。     

Moulds and mycotoxins in sorghum stored in traditional containers in India

Various traditional containers have been used in India for storage of sorghum grains. Sorghum is susceptible to fungal infestation and toxin elaboration. The present study relates to the mould and mycotoxin contamination (aflatoxin B₁ and T-2 toxin) in stored sorghum in different storage containers viz. “Kotlu” (Storage rooms), earthenware pots, gunny bags and reed baskets. Aspergillus sp. and Fusarium sp. were the prominent genera and the “Kotlu” form of storage was most susceptible to fungal attack. Storage treatment had little effect on fungal contamination, but despite the fungal infestation, the mycotoxin contamination was found to be very low.     

中国固态发酵白酒中功能细菌研究进展

细菌是白酒酿造3大类微生物之一,其在白酒生产中有着重要的作用,如:芽孢杆菌、乳酸菌、放线菌和梭菌等,它们能产生酯类、有机酸、吡嗪、萜烯等微量成分,从而影响白酒的风味与品质。基于细菌在白酒中的重要功能以及微生物分离培养技术和分析检测技术的进步,近年来相关研究越来越深入。该文综述了近年来白酒功能细菌的研究进展,介绍了酿酒各个环节中主要功能细菌及其在白酒中的作用,旨在为白酒功能细菌的研究提供参考。     

Aflatoxins in black tea in Iran

Aflatoxins (AFs) are highly toxic, and carcinogenic secondary fungal metabolites and have been detected in various food commodities. In this regard, 40 black tea samples including domestic and imported black tea were analysed for aflatoxin contamination by high-performance liquid chromatography using a post-column derivatisation procedure (Kobra cell) with fluorescence detection. Samples were randomly collected in 2010 from Tehran markets. The results revealed that 30 among 40 samples were contaminated with aflatoxins (27.5% of the total). Mean AFB1 content was 10.0 ng/g and mean of aflatoxin total was 12.07 ng/g for the 11 contaminated samples.