Closed system anaesthesia in dogs using liquid sevoflurane injection; evaluation of the square-root-of-time model and the influence of CO2 absorbent

Objective To determine whether predictable alveolar concentrations of sevoflurane are reliably produced in dogs when liquid sevoflurane is injected into closed circuit breathing systems, as calculated by Lowe's square‐root‐of‐time anaesthetic uptake model, and to confirm the validity of the model using soda lime and calcium hydroxide lime. Study design Prospective clinical study. Animals Eleven healthy dogs with a mean body mass of 34 ± 9 kg scheduled for pelvic limb orthopaedic surgery. Materials and methods Following pre‐anaesthetic medication, anaesthesia was induced with propofol and maintained with sevoflurane in a closed circle system. Epidural anaesthesia was performed with morphine and bupivacaine. Liquid sevoflurane was injected into the circuit by syringe, using dosages and time intervals derived from Lowe's square‐root‐of‐time anaesthetic uptake model. The target alveolar concentration chosen was 1.1 × MAC (2.6% end‐tidal sevoflurane). Either soda lime (group S; n = 6) or calcium hydroxide lime (Amsorb; group A; n = 5) were used for CO₂ absorption. Sevoflurane concentration and the respiratory gas composition were measured with an infrared gas analyser. Results End‐tidal sevoflurane concentrations were close to the predicted value of 2.6% at 9 minutes (2.53 ± 0.1% group S; 2.60 ± 0.26% group A) and 16 minutes (2.55 ± 0.30 group S; 2.52 ± 0.28% group A) but declined thereafter to reach 50% (group S) and 64% (group A) of the predicted value at 121 minutes. There was a constant trend towards higher end‐tidal sevoflurane concentrations in group A but the difference was not statistically significant. Conclusions The square‐root‐of‐time model leads to significantly lower alveolar concentrations than expected, suggesting that the rate of sevoflurane uptake in dogs declines less rapidly than predicted. The use of Amsorb tends to reduce the deviation from predicted concentrations. Clinical relevance The model used in this study provided only an approximate guide to the volume of liquid sevoflurane required. Consequently, the definitive dose schedule must be based on measured anaesthetic concentrations and clinical monitoring.     

花粉治疗前列腺增生的研究进展

对花粉治疗前列腺的实验室研究和临床应用进行了综述,初步探讨了其作用机理,并指出花粉制剂在治疗前列腺增生方面的研究进展。     

提高CO2和硝氮浓度对羽毛藻生化组成和营养盐吸收的影响

以羽毛藻为研究材料,利用CO_2培养箱通入不同CO_2浓度的空气进行培养,探究在高浓度CO_2和高浓度硝氮条件下羽毛藻生理生化的变化。结果表明,高浓度CO_2或硝氮都能显著促进藻体的生长,高碳高氮下藻体的相对生长率比低碳低氮组高出63.77%。另外,高浓度CO_2会使藻体中的叶绿素、类胡萝卜素、藻红蛋白、藻蓝蛋白、可溶性蛋白和可溶性碳水化合物的含量下降,而使硝酸还原酶活性升高,其中明显的表现为高碳低氮组叶绿素a含量比低碳低氮组降低了39.01%,高碳高氮组比低碳高氮组降低了49.26%,相应类胡萝卜素高碳组分别降低了47.62%和43.24%,增加硝氮浓度能够提高藻体中色素含量,可溶性蛋白和可溶性碳水化合物的含量;在高浓度硝氮下,提高CO_2浓度能使硝酸盐和磷酸盐的吸收率显著升高。由此得知大气CO_2浓度升高或海水富营养化会促进羽毛藻的生长,并且这两个条件的改变会对羽毛藻在生化组成和营养盐吸收方面产生深刻的影响。     

琅琊鸡胚MSX2基因克隆及发育性表达变化

【目的】 克隆鸡Msh同源框2(Msh-homeobox 2,MSX2)基因,并对其进行生物信息学和胚胎期表达模式分析,为进一步研究MSX2基因的结构和功能提供支持。【方法】 对80枚琅琊鸡种蛋进行孵化,分别于孵化期第1、2、3、4、5、6、9、12、15、18天采集样品(1~6胚龄采集整胚,9、12、15、18胚龄分别采集心脏和肝脏),提取总RNA,利用RT-PCR方法扩增并克隆MSX2基因,对其进行生物信息学分析;利用实时荧光定量PCR技术分析MSX2基因在琅琊鸡鸡胚和组织中的表达水平。【结果】 成功克隆了琅琊鸡胚MSX2基因,序列长度为818 bp,开放阅读框为780 bp,编码259个氨基酸。琅琊鸡MSX2氨基酸序列与日本鹌鹑、秃鹰和仓鸮的相似性最高,均为99.23%,与山羊的相似性最低,为74.54%;系统进化树分析结果显示,琅琊鸡与日本鹌鹑聚为一类。生物信息学分析表明,MSX2蛋白分子质量为28 235.18 u,等电点(pI)为9.71,没有信号肽和跨膜域,为不稳定的亲水性蛋白,主要分布在细胞核(60.9%);存在37个磷酸化位点、8个O-糖基化位点和1个N-糖基化位点;二级结构主要由无规则卷曲(63.32%)和α-螺旋(28.19%)组成。实时荧光定量PCR分析表明,MSX2基因在整胚(1~6胚龄)中的表达水平呈现先上升后下降趋势,且在4胚龄时表达水平最高,极显著高于1、2、3胚龄(P<0.01);MSX2基因在12胚龄鸡心脏中的表达水平极显著低于9胚龄(P<0.01);在9~18胚龄鸡肝脏中的表达量呈逐渐下降趋势,且在9胚龄鸡肝脏中表达水平最高(P<0.05)。【结论】 试验成功克隆了琅琊鸡MSX2基因序列,其表达模式在不同胚龄和同一胚龄不同组织间存在差异,为进一步探索琅琊鸡MSX2基因的结构和功能奠定了基础。     

玉屏风散对小鼠β防御素-2基因表达的影响

研究玉屏风散益气固表、提高机体对环境病因抵抗力的机理。实验组6只小鼠以玉屏风散水煎液灌胃10 d,对照组6只小鼠给予同体积生理盐水,处死动物后提取肺组织总RNA,通过实时荧光定量PCR测定小鼠在灌服玉屏风散水煎液后β防御素-2基因表达水平。结果实验组小鼠β防御素-2基因的相对表达量是对照组的9.327倍。表明玉屏风散增强机体抵抗力与其可上调β防御素-2基因的表达从而提高机体非特异性免疫力有关。     

蜂花粉中脂类对蜜蜂的作用

蜂花粉是蜜蜂主要的饲粮来源,对蜜蜂具有重要的营养作用。蜂花粉中脂肪酸、甾醇等脂类物质丰富,对蜜蜂采食、抗菌、寿命等均有影响。本文对蜂花粉中的脂类进行了分析,并就脂类对蜜蜂的营养、诱食和抗菌等作用,以及蜜蜂对脂类的营养需要进行阐述。     

斯氏艾美耳球虫ITS1-5.8S rRNA-ITS2序列的克隆及PCR检测方法的建立

通过对多种鸡球虫和松鼠球虫18SrRNA和28SrRNA进行序列比对分析,在18SrRNA 3′端和28SrRNA 5′端保守区设计艾美耳属通用引物,以斯氏艾美耳球虫洛阳分离株LY卵囊基因组DNA为模板首次成功克隆到斯氏艾美耳球虫完整的ITS1-5.8SrRNA-ITS2序列,其大小为1 178bp,其中ITS1序列长度为423bp,5.8SrRNA为155bp,ITS2为600bp,斯氏艾美耳球虫LY株ITS1/2序列高度变异,与鸡球虫、啮齿动物球虫的序列相似性低于60%。然后在斯氏艾美耳球虫ITS1/2序列超变区设计种特异引物,建立了灵敏、特异的PCR检测方法。本研究结果将为兔球虫强致病种的临床诊断和揭示兔球虫种群遗传特征提供有效的分子工具。     

Isolation and Identification of Orf Virus from Jiangsu Province and Phylogenetic Analysis of Their B2L Gene

The study was aimed to investigate prevalence of Orf virus (ORFV) in Jiangsu province in recent years and control Orf better. A total of 121 tissue samples were collected in some farms from 2013 to 2015 and subjected to PCR detection, viral isolation and phylogenetic analysis of B2L gene. Four samples were ORFV positive by PCR. The viruses were isolated by passaging in ovine fetal turbinate (OFTu) cells and MDBK cells, and were named as ORFV/Ovis/XZ/Jiangsu/2015/China, ORFV1/Ovis/DT/Jiangsu/2015/China, ORFV2/Ovis/DT/Jiangsu/2015/China and ORFV/Ovis/SL/Jiangsu/2015/China,respectively. The B2L gene was amplified and sequenced for the phylogenetic study. The nucleotide homology of these 4 strains was 98.5% to 100.0%. ORFV/Ovis/XZ/Jiangsu/2015/China, ORFV1/Ovis/DT/Jiangsu/2015/China and ORFV2/Ovis/DT/Jiangsu/2015/China, gathered into a cluster with SC-JY, GX-YB, JS-FX isolates and the nucleic acid homology of these strains was 97.8% to 100%. ORFV/Ovis/SL/Jiangsu/2015/China gathered into a cluster with LiaoNing, HuB and Gansu isolates, the nucleic acid homology was 98.8% to 98.9%. The nucleic acid homologies of 4 strains and ORFV strain China vaccine was 96.8% to 98.1%. The result showed that the ORFVs in Jiangsu province might be from different source. For controlling the spreading of this virus, it was necessary to carry out deep epidemiological survey in Jiangsu province.     

毒害艾美耳球虫初次感染雏鸡免疫器官IL-2和淋巴细胞增殖功能变化

应用组织匀浆涂片和酸性α-醋酸萘酯酶（ANAE）染色及细胞培养技术和四甲基偶氮唑盐（MTT）测定法对毒害艾美耳球虫（eimeria necatrix，E．necatrix）初次感染雏鸡免疫器官的T细胞比例、白细胞介素-2（interleukin-2，IL-2）诱生活性、T细胞和B细胞对ConA或PMA的增殖功能的动态变化进行了较全面系统的研究。结果发现，E．necatrix初次感染雏鸡，其胸腺和脾脏T细胞比例分别于感染后7～21d和7～24d明显高于对照雏鸡；IL-2诱生活性分别于感染后16～18d和18～21d较对照雏鸡显著升高；T细胞对ConA的增殖反应分别在感染后14～16d和10～18d明显增加。法氏囊和脾脏B细胞对PMA的增殖反应分别于感染后14～24d和14～21d显著高于对照雏鸡。表明E．necatrix初次感染雏鸡免疫器官的IL-2调节及细胞免疫和体液免疫功能均明显提高。     

转Bt-cry1Ab玉米花粉对意大利蜜蜂生长发育及体内酶活性的影响

自10年前首次种植转基因植物以来,转基因作物已在全球得到大面积推广。这些转基因作物中绝大多数品种具有抗虫基因能够增强作物对靶标昆虫的抗性。同时转抗虫基因植物可能带来的生态安全和环境问题也引起了国际社会广泛的关注。鉴于此,本实验开展了转Bt-cry1Ab基因抗虫玉米花粉