蟾酥的药理作用与制剂开发(上)

１蟾酥的有效成分蟾酥为蟾蜍科动物中华大蟾蜍Bufobufogar－garizansCantor或黑眶蟾蜍BufomelanostictusSchneider等的耳后腺及皮肤腺分泌的白色浆液，经加工干燥而成的固体物，是重要的中药材。其化学成分复杂，有效成分总称为蟾蜍毒素类（Bufotoxins），包括：１．１甾体强心     

蟾酥方剂的制作

1 鲜蟾酥及乳蟾酥 从蟾蜍耳后腺及皮肤腺刮取蟾酥浆后，置人容器中（忌用金属器具，以免浆液变色），加入95％乙醇密闭浸渍，配剂时取出沥去乙醇即为鲜蟾酥。也有将蟾酥浆加白酒（或酒精，按1：2）浸渍（密闭），搅拌或研磨，然后回收酒精，干燥研成细粉，称为乳蟾酥，供配剂用。     

蟾蜍产品的化学成分及药理作用与兽药制剂的开发应用

本文综述蟾酥（毒）和蟾蜍衣的化学成分及其药理作用,供开发兽医制剂及临床应用参考。     

蟾酥对产气肠杆菌抑制作用的方差分析和相关分析

把采自中华大蟾蜍的蟾酥用蒸馏水稀释成4、6、8、10mg／mL共4种浓度，作为因素A，用LB液体培养基将活化的产气肠杆菌原液按1：10^4和1：10^5稀释，作为因素B，采用二因子（A和B）方差分析观察了蟾酥对产气肠杆菌抑菌圈直径的影响，并分析了蟾酥浓度与抑菌圈直径之间的相关关系。结果显示，蟾酥浓度与抑菌圈直径之间存在显著正相关（r=0．988～0．997）；不同浓度的蟾酥溶液对产气肠杆菌均有抑制作用；且随着蟾酥浓度的升高，抑制作用加强。     

皮下埋植蟾酥治疗猪无名高热

皮下埋植蟾酥治疗猪无名高热李智（湖北省京山县杨集兽医站４３１８０５猪无名高热症是颇为棘手的猪多发病。笔者经多年实践，筛选出以皮下埋植蟾酥法疗效最佳。１蟾酥的采集以夏季捕捉为宜，将捕捉的蟾蜍装入塑料袋里（１只／袋为宜），袋口用橡皮筋扎紧，双手挤压背部，...     

养蟾蜍采蟾衣取蟾酥有误区

目前社会上将人工养蟾蜍采蟾衣取蟾酥炒得火热，笔者有6年养蟾采天然蟾衣、取蟾酥经验，觉得一些媒体和少数养殖场家宣传有误区。     

喉炎净散中蟾酥的薄层鉴别

采用薄层色谱法对中药喉炎净散中的蟾酥进行定性鉴别。用硅胶GF254的CMC-Na薄层板，以环已烷-氯仿-丙酮（5：3：3）为展开剂，紫外灯（254nm或365)相检视。检测结果表明本法能较好地分离喉炎净散中的各种成分，可对蟾酥进行质量监控。该法设备简易，结果可靠，专属性高，可作为含蟾酥制剂的质量控制方法。     

养蟾蜍采蟾衣取蟾酥的误区

目前，社会上对人工养蟾蜍采蟾衣取蟾酥炒得火热，我从自己六年养蟾采天然蟾衣、取蟾酥的经验中，觉得一些媒体和少数养殖场家在宣传上有不少误区。[第一段]     

蟾酥方剂的制作

<正>1鲜蟾酥及乳蟾酥从蟾蜍耳后腺及皮肤腺刮取蟾酥浆后,置入容器中(忌用金属器具,以免浆液变色),加入95%乙醇密闭浸渍,配剂时取出沥去乙醇即为鲜蟾酥。民间将蟾酥浆加白酒(或酒精,按1:2)浸渍(密闭),搅拌或研磨,然后回收酒精、干燥、研成细粉,称为乳蟾酥,供配剂用。也可取蟾酥块,按上法浸渍,研磨成细粉后,回收酒精、干燥后供用。     

蟾酥注射液质量标准的初步研究

为初步建立兽用蟾酥注射液的质量标准,采用薄层层析法对蟾酥进行鉴别,采用紫外分光光度法对蟾酥进行含量测定,并且在试验中采用掩蔽法消除抗氧化剂干扰,测定样品中水溶性吲哚类总生物碱的含量。结果表明,薄层色谱图像斑点较清晰,与相应标准品对照整齐;平均回收率为98.92%,变异系数为1.00%,说明该方法可准确检测蟾酥注射液中蟾酥的含量。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein