CaMV基因Ⅵ在拟南芥上的遗传转化及交叉保护

通过对ＣａＭＶＣＡＢＢ－ＢＪＩ和Ｂａｒｉ－１株系基因Ⅵ的克隆和转化，在根癌农杆菌菌种ＧＶ３１０１的介导下，利用真空渗入法获得了转化ＣＡＢＢ－ＢＪＩ和Ｂａｒｉ－１基因Ⅵ的拟南芥转基因植株。分子检测表明，基因Ⅵ已整合进拟南芥基因组并有不同程度的表达。在转基因植株中，出现了类似病毒感染症状、多生长点及花粉生活力较低等个体的变异株。而多数转基因植株（占转基因植株７０．４％）为无症状的正常植株。对转化ＣａＭＶＢａｒｉ－１株系基因Ⅵ的９个无症状转基因株系接种ＣａＭＶＣＡＢＢ－ＢＪＩ病毒抗性表明，９个转基因株系表现出了不同的抗性     

The effect of different combinations of lignocaine,ketoprofen, xylazine and tolazoline on the acute cortisol response to dehorning in calves

AIMS: The aims of this study were (a) to evaluate the effect of xylazine and tolazoline, with and without lignocaine, on the cortisol response of calves following amputation dehorning and (b) to assess the effect of a non-steroidal anti-inflammatory drug (ketoprofen) and local anaesthesia on the cortisol response of calves to amputation dehorning.

METHODS: Plasma cortisol concentrations were measured in 100 dehorned or non-dehorned 3-month-old calves over an 8-h period following five different sedative/analgesic or control treatments. Sedative/analgesic treatments were: control (no anaesthesia); local anaesthesia and ketoprofen; local anaesthesia and xylazine; local anaesthesia, xylazine and tolazoline; and xylazine only. Within each sedative/analgesic treatment group, half the calves (n=10 per group) were amputation dehorned and half were not dehorned.

RESULTS: The change in plasma cortisol concentrations in calves dehorned after being given ketoprofen and local anaesthesia did not differ significantly from that of non-dehorned control calves for at least 8 h. In contrast, the cortisol response of dehorned calves not given analgesic drugs peaked 30 min after dehorning and lasted >4 h. Xylazine injected before dehorning significantly reduced but did not eliminate the peak of the cortisol response. When both xylazine and local anaesthesia were administered before dehorning the peak in the cortisol response was virtually eliminated. In the dehorned calves that received xylazine with or without local anaesthesia, cortisol concentration increased significantly 3 h after dehorning and did not return to baseline until at least 5 h later. When tolazoline was administered shortly after xylazine, it caused a marked cortisol response, higher than the response to any other treatment.

CONCLUSIONS: Combining ketoprofen and local anaesthesia minimised the cortisol response, and by inference the pain- induced distress, following amputation dehorning in calves. Xylazine reduced the initial cortisol response to dehorning but not as much as when local anaesthesia was also given. The increase in cortisol concentration from 3–8 h after dehorning in calves given xylazine alone or in combination with local anaesthesia suggests that calves experienced pain-induced distress during this time and that xylazine had no long-term analgesic effect. Tolazoline, used to reverse the sedative effects of xylazine, caused a marked cortisol response in calves via a mechanism which remains unclear.     

Dexamethasone‐Induced Eosinopenia is Associated with Lower Progesterone Production in Cattle

Eosinophilic cells accumulate in the capillaries of the bovine Graafian follicle shortly before ovulation and in the early developing corpus luteum (CL). Suppressing the migration of these eosinophilic cells by dexamethasone allowed us to evaluate their possible function in the CL development. Brown Swiss cows (n = 10) were randomly subdivided into two groups (n = 5). Every group was used once as control group and once as experimental group with two oestrous cycles between each treatment. Eighteen hours (h) after oestrus synchronization, dexamethasone or saline was given. Ovulation was induced 24 h later with gonadotropin‐releasing hormone. Another injection of dexamethasone or saline was given 12 h later. Eosinophilic cells in the blood were counted daily until day 7 after the first dexamethasone injection. The collection of ovaries took place at days 1, 2 and 5. Gene expression, protein concentration and location of angiogenic factors, chemokines, insulin‐like growth factor 1 (IGF1) and eosinophilic cells were studied. No eosinophilic cells were found in the CL of the treatment group. Blood progesterone decreased significantly in the dexamethasone group from day 8 to 17. The protein concentration of FGF2 increased significantly in CL tissue at day 2 and VEGFA decreased. Local IGF1 gene expression in the CL was not regulated. We assume from our data that the migration of eosinophilic cells into the early CL is not an essential, but an important stimulus for angiogenesis during early CL development in cattle.     

Survival times for cats with hyperthyroidism treated with iodine 131, methimazole, or both: 167 cases (1996-2003)

OBJECTIVE: To compare survival times for cats with hyperthyroidism treated with iodine 131, methimazole, or both and identify factors associated with survival time. DESIGN: Retrospective case series. ANIMALS: 167 cats. PROCEDURE: Medical records of cats in which hyperthyroidism had been confirmed on the basis of high serum thyroxine concentration, results of thyroid scintigraphy, or both were reviewed. RESULTS: 55 (33%) cats were treated with 131I alone, 65 (39%) were treated with methimazole followed by 131I, and 47 (28%) were treated with methimazole alone. Twenty-four of 166 (14%) cats had preexisting renal disease, and 115 (69%) had preexisting hepatic disease. Age was positively correlated (r = 0.4) with survival time, with older cats more likely to live longer. Cats with preexisting renal disease had significantly shorter survival times than did cats without preexisting renal disease. When cats with preexisting renal disease were excluded, median survival time for cats treated with methimazole alone (2.0 years; interquartile range [IQR], 1 to 3.9 years) was significantly shorter than median survival time for cats treated with 131I alone (4.0 years; IQR, 3.0 to 4.8 years) or methimazole followed by 131I (5.3 years; IQR, 2.2 to 6.5 years). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that age, preexisting renal disease, and treatment type were associated with survival time in cats undergoing medical treatment of hyperthyroidism.     

Translating the terrestrial mitigation hierarchy to marine megafauna by‐catch

In terrestrial and coastal systems, the mitigation hierarchy is widely and increasingly used to guide actions to ensure that no net loss of biodiversity ensues from development. We develop a conceptual model which applies this approach to the mitigation of marine megafauna by‐catch in fisheries, going from defining an overarching goal with an associated quantitative target, through avoidance, minimization, remediation to offsetting. We demonstrate the framework's utility as a tool for structuring thinking and exposing uncertainties. We draw comparisons between debates ongoing in terrestrial situations and in by‐catch mitigation, to show how insights from each could inform the other; these are the hierarchical nature of mitigation, out‐of‐kind offsets, research as an offset, incentivizing implementation of mitigation measures, societal limits and uncertainty. We explore how economic incentives could be used throughout the hierarchy to improve the achievement of by‐catch goals. We conclude by highlighting the importance of clear agreed goals, of thinking beyond single species and individual jurisdictions to account for complex interactions and policy leakage, of taking uncertainty explicitly into account and of thinking creatively about approaches to by‐catch mitigation in order to improve outcomes for conservation and fishers. We suggest that the framework set out here could be helpful in supporting efforts to improve by‐catch mitigation efforts and highlight the need for a full empirical application to substantiate this.     

高效液相色谱法测定伊维菌素脂质体药物的含量及包封率

本试验旨在建立伊维菌素脂质体载体药物含量及包封率测定的高效液相色谱法。Waters surfire C18柱(150 mm×2.1 mm,5 μm),流动相为乙腈—甲醇—水(62∶30∶8),流速1 mL/min,检测波长245 nm,进样量10 μL,柱温30 ℃。采用凝胶过滤法、透析法、冷冻超速离心法、超滤离心法4种方法对脂质体与药物进行分离。结果表明,在优化色谱条件下伊维菌素与辅料及溶剂峰均得到良好分离,伊维菌素在1～50 μg/mL浓度范围内线性关系良好(r=0.9998,n=5),最终采用超速冷冻离心法可将脂质体与药物很好的分离,伊维菌素脂质载体的包封率可达98.54%±1.6%。该方法准确可靠、简单快速,可用于伊维菌素脂质体载体药物含量及包封率的测定。