藏药材在鸡胚成纤维细胞体系中安全浓度的测定

用MTT法测定了藏菖蒲、红景天、决明子、灵芝菌盖、灵芝菌柄、龙胆、天冬、降香、乳香、仁青芒觉、二十五味珍珠丸和二十五味松石丸12种藏药在鸡胚成纤维细胞（CEF）培养体系中的安全浓度。结果表明,各藏药的最大安全浓度分别为红景天31．25ng／mL,天冬、降香、决明子和二十五味松石丸为62．5μg／mL,乳香为125μg/mL、二十五味珍珠丸为250μg／mL,藏菖蒲和灵芝菌柄为1000μg／mL,龙胆和仁青芒觉为2500μg／mL,灵芝菌盖为5000μg／mL;藏菖蒲在1．954～500μg／mL、天冬在1．954～15．625μg／mL、决明子在1．954～3．907μg／mL、灵芝菌柄在1．954～7．813μg／mL、仁青芒觉在19．54～1250μg／mL、龙胆在312．5～625μg／mL范围内能显著促进细胞生长。     

丝裂霉素C和γ射线对小鼠胎儿成纤维细胞饲养层制备的影响

用丝裂霉素C和γ射线对小鼠胎儿成纤维细胞进行处理，观察它们对小鼠胎儿成纤维细胞分裂与存活的影响。结果表明，小鼠胎儿成纤维细胞用不同浓度的丝裂霉素C或不同强度的)，射线处理一定时间(5μg／mL 4h、10μg／mL 1～4h、20μg／mL 1．0～2．5h或14Gy 1h、21Gy 1h、28Gy 1h)，能有效地抑制其分裂，且不影响其活力。     

脂多糖对奶牛子宫内膜上皮细胞毒性作用研究

本试验通过传代培养奶牛子宫内膜上皮细胞,以0.1μg/mL、1μg/mL、10μg/mL、50μg/mL、100μg/mL、500μg/mL、1000μg/mL 7个LPS浓度梯度刺激细胞,分别于刺激后12h、24h、36h 3个时间段做MTT细胞毒检测,同时进行细胞形态学观察,研究LPS对子宫内膜上皮细胞的毒性作用。结果发现：0.1μg/mL、1μg/mLLPS组细胞形态学无明显改变;10μg/mL、50μg/mL、100g/mL LPS组细胞形态学与对照组相比有明显改变,500μg/mL、1000μg/mL LPS组细胞发生裂解、死亡。MTT试验结果表明LPS对细胞的抑制作用呈浓度与时间依赖关系,随着LPS浓度的增加和刺激时间的延长,细胞抑制率明显增加,细胞活力明显降低。     

正己酸对大肠杆菌与金黄色葡萄球菌的抑制效果研究

对大肠杆菌和金黄色葡萄球菌进行正己酸的抗性试验,以研究正己酸对病原菌的抑制作用。试验采用等浓度梯度稀释、光密度值测定、平板涂布方法、牛津杯法,分别测定大肠杆菌及金黄色葡萄球菌的的最小抑菌浓度(minimum inhibitory concentration,MIC)以及最小杀菌浓度(minimum bactericidal concentration,MBC),绘制1/2MIC以及MIC处理过的大肠杆菌以及金黄色葡萄球菌的生长曲线,抑菌圈直径,结合扫描电镜图片分析最小杀菌浓度处理后的细胞形态结构的变化。结果表明:正己酸对大肠杆菌的最小抑菌浓度为700μg/mL、对金黄色葡萄球菌的最小抑菌浓度为1 000μg/mL;对大肠杆菌的最小杀菌浓度为1 000μg/mL、对金黄色葡萄球菌的最小杀菌浓度为1 300μg/mL;当正己酸浓度为1 600μg/mL时,电镜下,大肠杆菌数量较少,金黄色葡萄球菌数量少且呈现出细胞破裂萎缩现象。综上,正己酸对大肠杆菌和金黄葡萄球菌有抑制作用,破坏了金黄葡萄球菌的细胞膜结构。     

铜对体外仔猪软骨细胞增殖和细胞骨架的影响

体外分离、培养仔猪关节软骨细胞,在细胞培养液中分别添加铜0、7.8、15.6、31.2、62.5μmol/L。结果表明,软骨细胞在4种铜浓度中可存活并增殖,但随铜浓度的增加,其存活率、增殖率、3H-TdR掺入率有明显的差异,且能破坏软骨细胞骨架。培养液中添加铜31.2μmol/L,对软骨细胞的增殖作用最强,增殖率、3H-TdR掺入数显著高于对照组(P<0.01),软骨细胞形态及骨架均正常。表明31.2μmol/L铜浓度是促进体外软骨细胞增殖的最适浓度。     

铜对体外仔猪软骨细胞增殖和自分泌IGF—I、IGFBP的影响

体外分离、培养仔猪关节软骨细胞，然后在细胞培养液中分别添加0、7．8、15．6、31．2、62．5μmol/L铜。结果表明，软骨细胞在4种浓度的铜中可存活并增殖，而且能增加胰岛素样生长因子（IGF－I）、胰岛素样生长因子结合蛋白（IGFBP3）的分泌量。但随铜浓度的增加，其存活率、增殖率、^3H-TdR掺入率及IGF－I、IGFBP3的分泌量有明显的差异。且以培养液中添加31．2μmol/L铜对软骨细胞的增殖作用最强，增殖率、^3H-TdR掺入数、IGF－I、IGFBP3的分泌量显著高于对照组9P＜0．01）。表明31．2μmol/L铜浓度是促进体外软骨细胞增殖和自分泌IGF－I、IGFBP3的最适浓度。     

小鼠胎儿成纤维细胞饲养层制备的研究

研究主要探讨在制备小鼠胎儿成纤雏饲养层中，不同处理条件对小鼠胎儿成纤雏细胞分裂与存活的影响。结果表明：小鼠胎儿成纤雏细胞用适当处理浓度的丝裂霉素-C或适当强度的γ-射线处理一定的时间(10μg／mL 1-4h,20μg／mL 1—2．5h或21Gy和28Gy各处理1h)，能有效地抑制其分裂，且不影响其活力。     

沙冬青总生物碱体外抗牛病毒性腹泻病毒

为了探讨沙冬青总生物碱抗牛病毒性腹泻病毒的作用,采用药毒同加、先药后毒、先毒后药3种不同途径进行体外抗病毒试验,观察病毒致牛肾原代细胞病变,并采用MTT比色法测定D492值,计算病毒抑制率。结果表明,病毒的TCID50为10^-5.29／0．1mL;沙冬青种子总生物碱的药物安全质量浓度为0．39g／L;与病毒对照组相比,当质量浓度为0．16g／L和0．32g／L时,沙冬青种子总生物碱对牛病毒性腹泻病毒有较强的直接杀伤作用,可抑制病毒的复制,能有效保护经病毒感染的牛肾原代细胞,使细胞活性增强,并减弱病毒导致的细胞病变效应,但对病毒没有明显的阻断作用。综上所述,沙冬青种子总生物碱具有较强的抗牛病毒性腹泻病毒的作用。     

络合铜对藻类、车轮虫的杀灭试验及对鳜鱼的安全性试验

络合铜杀灭藻类和车轮虫试验及对鳜鱼的安全性试验表明，水中络合铜在1．2μg／mL浓度时就可以有效地杀灭寄生于实验鱼鳃部的车轮虫，在2．0μg/mL浓度时可以有效地杀灭池塘微囊藻。相对硫酸铜来说，络合铜对鳜鱼的毒性较小，当水中浓度达到6．0μg／mL时对鳜鱼造成的死亡率也只有6．7％；而慢性毒性试验中，首日投药使水中药物浓度为0．6μg／mL，以后每天投与同样量的药物至第5天，实验鱼也未见任何异常表现。因此，对鳜鱼使用络合铜来杀灭纤毛虫类寄生虫，在有效使用浓度(1．2μg／mL)下是安全的。     

优环霉素对体外鸡毒支原体的抑菌试验和对鸡毒支原体病的治疗试验

用优环霉素原粉对鸡毒支原体(病)进行了体内外的治疗、抑菌试验。体外试验结果表明：当优环霉素在培养基中有效药物浓度达到0．0625μg/mL时，能有效地抑制试管中鸡毒支原体的生长繁殖。体内试验结果显示：当饮水中药物浓度达到250μg／mL时，能一定程度上减少由于鸡毒支原体病引起的死亡，较明显地提高鸡体增重，随着药物浓度的加大这种作用更加明显；当药物浓度达到500μg／mL时，能较大幅度地降低气囊损伤。然而，所有药物治疗组均不能彻底抑制体内人工感染的鸡毒支原体而使血清学变为阴性反应。     

转柞蚕抗菌肽D基因辣椒的目的基因及表达产物检测

应用现代生物技术,从核酸和蛋白质水平对转柞蚕抗菌肽D基因辣椒第4代的目的基因进行了检测。发现所分离的柞蚕抗菌肽D基因与原设计的序列一样;辣椒组织中也含有抑菌物质,经与天然抗菌肽D对比,表明抗菌肽D基因得到了表达。     

日粮中添加天蚕素抗菌肽对断奶仔猪生产性能和血液生化指标的影响

为考察天蚕素抗菌肽对断奶仔猪生产性能和血清生化指标的影响,选用28日龄、体重相近、健康的北京原种黑猪断奶仔猪192头,采用单因子设计,按体重相近、遗传基础相似的原则,完全随机分为4个处理组:对照组饲喂基础日粮,试验组在基础日粮基础上分别添加不同剂量的天蚕素抗菌肽(试验Ⅰ组:180 g/t,试验Ⅱ组:250 g/t,试验Ⅲ组:320 g/t)。每个处理组设三个重复,每个重复16头猪,试验期为32 d。试验结果表明:饲料中添加适量的天蚕素抗菌肽能够提高断奶仔猪平均日增重,但各组间差异不显著(P>0.05);显著降低料重比(P<0.05);提高血液中的免疫球蛋白含量。因此,在断奶仔猪基础日粮中添加适量天蚕素抗菌肽能提高断奶仔猪的生产性能和机体免疫性能,且本次试验中,天蚕素抗菌肽的最适添加量为320 g/t。     

Macrophages and giant cell proliferation associated with bone protein synthesis and calcification in the trachea and bronchi of rabbits intoxicated with Solanum glaucophyllum

A histopathologic, immunohistochemical, and ultrastructural study of the trachea and the bronchi of 6 rabbits experimentally intoxicated with the calcinogenic plant Solanum glaucophyllum was performed. Histologically, infiltration of the mucosa and the submucosa of the trachea and the bronchi by macrophages, multinucleated giant cells, a few lymphocytes and mast cells, and calcium deposits in the basal lamina of the epithelium and in elastic fibers were observed. Expression of osteocalcin, osteonectin, and osteopontin was detected in the mucosa, lamina propria, and epithelium. Electron microscopic study of the corresponding areas showed numerous macrophages in the process of fusion to form multinucleated giant cells, activated mesenchymal cells, and calcium precipitation in the basal lamina of epithelium and in elastic fibers. It is suggested that the high levels of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) in the plant induces macrophage proliferation, multinucleated giant-cell formation, mesenchymal cell activation, bone-protein synthesis, and calcification. In addition, the synthesis of 1,25(OH)2D3 by local macrophages may have contributed to the calcification.     

天蚕素和合生素对AA肉鸡小肠黏膜形态和小肠免疫细胞的影响

为研究日粮中添加天蚕素、合生素对AA肉鸡小肠黏膜形态及免疫细胞的影响,试验选用480只1日龄健康AA肉鸡,随机分为4组,每组4个重复,每个重复30只鸡。对照组（Ⅰ组）饲喂基础日粮,试验组（Ⅱ~Ⅳ组）分别在基础日粮中添加0.5%天蚕素、0.3%合生素、0.5%天蚕素+0.3%合生素。试验期42 d。结果显示,与Ⅰ组相比,Ⅳ组十二指肠、回肠绒毛高度极显著升高（P<0.01）;Ⅱ组空肠和回肠、Ⅲ组小肠各段隐窝深度显著或极显著降低（P<0.05;P<0.01）;Ⅱ、Ⅲ组小肠各段和Ⅳ组十二指肠、回肠绒毛高度/隐窝深度显著或极显著升高（P<0.05;P<0.01）;Ⅱ组空肠绒毛宽度显著降低（P<0.05）,Ⅲ组十二指肠和空肠、Ⅳ组空肠和回肠绒毛宽度均极显著降低（P<0.01）;Ⅱ、Ⅲ组空肠黏膜厚度显著升高（P<0.05）,Ⅳ组小肠各段黏膜厚度均极显著升高（P<0.01）。Ⅱ组回肠上皮内淋巴细胞数量显著升高（P<0.05）,Ⅲ组十二指肠、Ⅳ组小肠各段上皮内淋巴细胞数量极显著升高（P<0.01）;Ⅲ组十二指肠、Ⅳ组十二指肠和回肠杯状细胞数量极显著升高（P<0.01）;Ⅳ组空肠肥大细胞数量显著升高（P<0.05）。综上所述,天蚕素、合生素单独或联合添加均能改善AA肉鸡小肠黏膜结构,促进小肠黏膜免疫细胞增殖,联合添加效果最佳。     

Investigation of morphological changes of HPS membrane caused by cecropin B through scanning electron microscopy and atomic force microscopy

BackgroundAntimicrobial peptides (AMPs) have been identified as promising compounds for consideration as novel antimicrobial agents.ObjectivesThis study analyzed the efficacy of cecropin B against Haemophilus parasuis isolates through scanning electron microscopy (SEM) and atomic force microscopy (AFM) experiments.ResultsCecropin B exhibited broad inhibition activity against 15 standard Haemophilus parasuis (HPS) strains and 5 of the clinical isolates had minimum inhibition concentrations (MICs) ranging from 2 to 16 μg/mL. Microelectrophoresis and hexadecane adsorption assays indicated that the more hydrophobic and the higher the isoelectric point (IEP) of the strain, the more sensitive it was to cecropin B. Through SEM, multiple blisters of various shapes and dents on the cell surface were observed. Protrusions and leakage were detected by AFM.ConclusionsBased on the results, cecropin B could inhibit HPS via a pore-forming mechanism by interacting with the cytoplasmic membrane of bacteria. Moreover, as cecropin B concentration increased, the bacteria membrane was more seriously damaged. Thus, cecropin B could be developed as an effective anti-HPS agent for use in clinical applications.     

Effects of Cecropin and Synbiotics on the Intestinal Mucosal Morphology and Intestinal Mucosal Immune Cells of AA Broilers

In order to investigate the effects of cecropin and synbiotics on the intestinal mucosal morphology and intestinal mucosal immune cells of AA broilers. 480 of 1-day-old healthy AA broilers were chosen and randomly divided into 4 groups with 4 replicates per group and 30 broilers per replicate. The broilers in group Ⅰ(control group) were fed basal diet,while that in groups Ⅱ to Ⅳ were fed the basal diet supplemented with 0.5% cecropin,0.3% synbiotics,0.5% cecropin+0.3% synbiotics,respectively. The trial lasted for 42 days. The result showed that compared with group Ⅰ,the villus height of duodenum and ileum in group Ⅳ were extremely significantly increased (P<0.01).The crypt depth of jejunum and ileum in group Ⅱ,and that of small intestine in group Ⅲ were significantly or extremely significantly decreased (P<0.05;P<0.01).The villus height/crypt depth of small intestine in groups Ⅱ and Ⅲ,and that of duodenum and ileum in group Ⅳ were significantly or extremely significantly increased (P<0.05;P<0.01).The villus width of jejunum in group Ⅱ was significantly decreased (P<0.05),while the villus width of duodenum and jejunum in group Ⅲ,that of jejunum and ileum in group Ⅳ were extremely significantly decreased (P<0.01).The mucous thickness of jejunum in groups Ⅱ and Ⅲ were significantly increased (P<0.05),while that of small intestine in group Ⅳ was extremely significantly increased (P<0.01).The number of the intraepithelial lymphocyte of ileum in group Ⅱ was significantly increased (P<0.05),and that of duodenum in group Ⅲ and small intestine in group Ⅳ were extremely significantly increased (P<0.01).The number of the goblet cell of duodenum in group Ⅲ,duodenum and ileum in group Ⅳ were extremely significantly increased (P<0.01).The mast cell of jejunum in group Ⅳ was significantly increased (P<0.05).In conclusion,both the cecropin and synbiotics could improve the small intestine mucosal structure and promote the small intestine mucosal immunocompetent cells proliferation in AA broiler, and the effect of combined utilization would be better.     

低功率氦氖激光加血卟啉衍生物杀伤肿瘤细胞的超微结构研究

用低功率氦氖激光-血卟啉衍生物(HpD)所产生的光动力学(PDT)效应治疗小鼠S180纤维肉瘤已获得了一定的实验性疗效,在此基础上进行了PDT杀伤肿瘤细胞的超微结构研究。电镜观察结果发现:PDT疗法治疗后第1天,肿瘤细胞线粒体肿胀,有的线粒体的嵴断裂;第3天,线粒体基质聚集而出现空化灶,嵴消失,内质网扩张,微绒毛减少;治疗后第7天,线粒体基质溶解呈空泡化,细胞膜破坏,胞浆内有空泡,可见胞浆内容物溢出胞外,核糖体减少,核膜部分破坏,染色质聚集成团,核膜破坏消失;13天,细胞核溶解,核内容物溢出胞外。     

抗菌肽生物工程及其应用

柞蚕抗菌肽具有广谱杀菌功能。根据其氨基酸序列设计、合成抗菌肽D及CAD基因,转化于作物,包括烟草、辣椒、马铃薯、水稻、桑树及柑桔等,已培育出抗病株系及品种。抗菌肽基因转化于酵母中表达,通过发酵生产重组抗菌肽,代替抗生素用作饲料添加剂饲喂肉鸡、仔猪及对虾,对预防疾病、提高存活率、增加体重及降低料肉比有较好效果,已经在生产中应用。用抗菌肽配制成口腔及阴道消毒洗涤剂,能预防呼吸道疾病及阴道炎症。用抗菌肽制剂与生长因子配制成多种化妆品,已投放市场,取得较好经济效益。     

Vitamin D3 supplementation of cull cows: effects on longissimus and semitendinosus muscle tenderness

Previous studies have shown that supplementation of vitamin D3 to cow diets for 4 to 10 d before slaughter lowers Warner-Bratzler shear force (WBSF) values and increases sensory tenderness scores in beef cuts. The present study was conducted to evaluate the effects of vitamin D3 supplementation on muscle calcium concentration, WBSF values, and sensory tenderness ratings of LM and semitendinosus (ST) muscles from cull, predominately Angus, cows (eight cows per treatment). Treatments included 0 (control), 5 million IU, or 7.5 million IU of vitamin D3 supplemented daily for 7 d preslaughter. Twenty-four hours after slaughter, 2.54-cm-thick LM and ST muscle steaks were cut; aged for either 0, 7, 14, or 21 d (ST steaks aged for 7 d only); and frozen at -20 degrees C for WBFS and sensory analysis. Mean values for LM calcium concentration tended to increase (P = 0.14) with vitamin D3 supplementation (154, 176, and 183 microig/g, fresh basis, for 0, 5, and 7.5 million IU/d, respectively). After 7 d of aging, LM steaks from cows fed 7.5 million IU had lower (P < 0.05) WBSF values than 7-d steaks from controls and cows fed 5.0 million IU/d aged 7 d; however, vitamin D3 supplementation had no (P > 0.05) effect on WBSF values of ST steaks aged 7 d. Vitamin D3 supplementation did not (P > 0.05) affect sensory tenderness ratings for either LM or ST steaks at any aging period. Aging, however, had a linear (P < 0.001) effect on tenderness, with an increase in tenderness as aging time increased from 0 to 21 d. Thus, results from the present study indicate that vitamin D3 supplementation, at these levels and duration before slaughter, provided little benefit to muscle tenderness of beef from cull cows.