Effect of breed and gender on bovine liver cytochrome P450 3A (CYP3A) expression and inter-species comparison with other domestic ruminants

The cytochrome P450 (P450) superfamily represents a group of relevant enzymes in the field of drug metabolism and several exogenous or constitutional factors contribute to regulate its expression. Cattle represent an important source of animal-derived food-products and studies concerning the P450 expression are needed for the extrapolation of pharmacotoxicological data from one species to another and for the evaluation of the consumer's risk associated with the consumption of harmful residues found in foodstuffs. In the present study, possible breed-, gender- and species-differences in P4503A (the P450 subfamily more expressed in the human liver) expression were studied in vitro in Piedmontese (PDM) and Limousin (LIM) meat cattle breeds of both sexes and in domestic Ruminants (cattle, sheep and goats). Cytochrome P450 and P4503A contents as well as CYP3A-dependent drug metabolising enzymes (DME) were measured in liver microsomes. Significant lower levels of P450 (P < 0.001) and P4503A (P < 0.05) contents were observed in PDM vs. LIM of both sexes; the P4503A-dependent DME activities were significantly (P values ranging from 0.05 up to 0.001) higher in PDM cattle, particularly in males. A gender-effect in DME activities was noticed (P < 0.05) only in PDM male cattle. With regards to the species, the expression of both P4503A apoprotein and some of the related DME activities were more pronounced in sheep (P < 0.01 vs. cattle) and in goats (P < 0.05 vs. sheep; P < 0.01 vs. cattle) than in cattle. The significant differences in P4503A expression observed in LIM and PDM cattle are consistent with previously published data on strain- and breed-differences pointed out in rats and men. As far as a possible sex-effect is concerned, no clear-cut evidence is likely to be drawn. Finally, P4503A expression was more relevant in small ruminants.     

生物质炭对橡胶园土壤酸度及交换性能的影响

为合理运用热带农业废弃物改良酸性土壤,采用室内培养试验研究了加入15 g/kg和45 g/kg的椰炭、蔗炭、胶炭和蕉炭对橡胶园土壤酸度及交换性能的影响。结果表明:除加入蔗炭15 g/kg在培养第9 d、30~60 d和蔗炭45 g/kg的处理在培养第45 d外,四种生物质炭在两种添加量下在各培养时间内土壤pH均显著高于对照,土壤p H提升效果为蕉炭胶炭椰炭蔗炭,且不同生物质炭处理之间土壤p H提升效果差异显著;除添加蔗炭15 g/kg的处理外,其余三种生物质炭两种加入量均显著降低了土壤交换性酸和交换性铝含量,而土壤交换性氢仅在加入蔗炭45 g/kg和蕉炭15 g/kg、45 g/kg的处理上显著低于对照;此外,蕉炭、椰炭、蔗炭显著提高了土壤阳离子交换量和土壤盐基饱和度,但胶炭仅提高了土壤盐基饱和度。上述结果表明,蕉炭、胶炭、椰炭和蔗炭等热带农业废弃物生物质炭能提高橡胶园土壤p H,降低土壤交换性酸和交换性铝含量,从而改善橡胶园土壤酸度条件。同时,以上生物质炭也能提高土壤阳离子交换量和土壤盐基饱和度。可见,蕉炭、胶炭、椰炭和蔗炭等热带农业废弃物生物质炭可用于改良热带橡胶园酸性土壤,但不同种类生物质炭及其用量在土壤改良效果上存在差异。     

Diversity of insecticide resistance mechanisms and spectrum in European populations of the codling moth, Cydia pomonella

Only a few of the registered insecticides against Cydia pomonella L. are still effective in areas where insecticide resistance has emerged in this pest. Resistance mechanisms are multiple, and their lone or cumulative effects in a single population are not completely understood. A detailed estimation of resistance spectrum is still required to define the suitable insecticides to use against a given population. The efficacy of ten insecticides was therefore investigated together with the resistance mechanisms expressed in four laboratory strains and 47 field populations of C. pomonella from five countries. Bioassays were performed using topical applications of diagnostic concentrations on diapausing larvae, and resistance mechanisms were analysed on adults emerging from control insects. All populations exhibited a reduced susceptibility to at least one insecticide when compared with the susceptible laboratory strain. Cross-resistances were observed between azinphos-methyl or phosalone and more recent compounds such as spinosad and thiacloprid. Resistances to azinphos-methyl, diflubenzuron, spinosad, tebufenozide and thiacloprid were significantly correlated with mixed-function oxidase activity, while increased glutathione-S-transferase and reduced non-specific esterase activities were correlated with resistance to azinphos-methyl and emamectin, respectively. Conversely, resistances to azinphos-methyl, tebufenozide and thiacloprid were negatively correlated with increased esterase activity. None of the observed mechanisms explained the loss of susceptibility of populations to chlorpyrifos-ethyl, and no significant correlation was detected between resistance to deltamethrin and the presence of the kdr mutation. The suitability of such non-target instars to monitor insecticide resistance in field populations is discussed.     

Fusarium oxysporum f. sp. radicis‐vanillae is the causal agent of root and stem rot of vanilla

Root and stem rot (RSR) is a very detrimental disease of vanilla worldwide. Fusarium oxysporum is frequently associated with the disease but other Fusarium species are also reported. In this international study, 52 vanilla plots were surveyed in three of the most important vanilla producing countries (Madagascar, Reunion Island and French Polynesia) in order to determine the aetiology of RSR disease. Subsets from the 377 single‐spored Fusarium isolates recovered from rotten roots and stems in the surveys were characterized by molecular genotyping (EF1α and IGS gene sequences) and pathogenicity assays on Vanilla planifolia and V. ×tahitensis, the two commercially grown vanilla species. Fusarium oxysporum was shown to be the principal species responsible for the disease, representing 79% of the isolates recovered from the RSR tissues, 40% of which induced severe symptoms on inoculated plantlets. Fusarium oxysporum isolates were highly polyphyletic regardless of geographic origin or pathogenicity. Fusarium solani, found in 15% of the samples and inducing only mild symptoms on plantlets, was considered a secondary pathogen of vanilla. Three additional Fusarium species were occasionally isolated in the study (F. proliferatum, F. concentricum and F. mangiferae) but were nonpathogenic. Histopathological preparations observed in wide field and multiphoton microscopy showed that F. oxysporum penetrated the root hair region of roots, then invaded the cortical cells where it induced necrosis in both V. planifolia and V. ×tahitensis. The hyphae never invaded the root vascular system up to 9 days post‐inoculation. As a whole, the data demonstrated that RSR of vanilla is present worldwide and that its causal agent should be named F. oxysporum f. sp. radicis‐vanillae.     

不同地区、不同部位羊驼毛品质性状的研究

本研究旨在了解不同地区、不同部位羊驼毛品质的差异,为羊驼选育及羊驼毛生产提供参考数据。采集新疆野生动物园、新疆阿勒泰、新疆阿克苏、山西、天津地区羊驼颌、颈、肩、侧、股、背、腹部位共636份毛样,进行平均纤维直径、毛丛长度、净毛率、单纤维强力、有髓毛含量、无髓毛含量等性状的测定,分析不同地区及不同部位毛品质性状的差异,并进行最小二乘分析。结果表明,不同地区羊驼毛平均纤维直径、白度、亮度、原毛油脂含量、净毛率、毛丛自然长度、单纤维强力、断裂伸长百分比、有髓毛含量、无髓毛含量均存在极显著差异（P<0.01）;不同取样部位羊驼毛纤维直径、原毛油脂含量、毛丛自然长度、单纤维强力、含杂率存在极显著差异（P<0.01）,无髓毛含量和有髓毛含量存在显著差异（P<0.05）。以羊驼毛细度越细毛品质越优为准,结合单纤维强力、毛丛自然长度等性状,羊驼不同部位的毛纤维质量从高到低依次为：背、侧、股、肩、颈、颌及腹部。在育种中可将提高无髓毛含量作为新疆羊驼毛细度的选育目标,将提高净毛率和单纤维强力作为山西、天津羊驼毛育种方向,同时可考虑提高羊驼颈、颌、腹部的无髓毛含量,以提高羊驼整体毛品质水平。     

7味蒙药对大肠杆菌和金黄色葡萄球菌体外抑菌试验研究

为筛选出对金黄色葡萄球菌（Staphylococcus aureus,S. aureus）和大肠杆菌（Escherichia coli,E. coli）具有良好抑菌作用的蒙药,试验采用打孔法测定S. aureus和E. coli对石榴皮、诃子、小白蒿、黄芩、黄芪、苦参、铁线莲7味蒙药敏感程度,微量稀释法测定蒙药的最小抑菌浓度（minimal inhibitory concentration,MIC）,棋盘法测定敏感蒙药对S. aureus和E. coli的协同指数（fractional inhibitory concentration index,FICI）。结果显示：石榴皮、诃子、黄芩3味蒙药对S. aureus的抑菌圈直径为23.30~32.60 mm,MIC为0.98~7.80 mg/mL;石榴皮、诃子、黄芩3味蒙药对E. coli的抑菌圈直径为5.20~12.50 mm,MIC为7.80~31.50 mg/mL;石榴皮与诃子联合用药对S. aureus的FICI为1.00,为相加作用;诃子与黄芩、石榴皮分别联合用药对E. coli的FICI都为0.75,为相加作用。综上所述,石榴皮、诃子、黄芩3味蒙药对S. aureus综合抑菌效果达极度敏感或高度敏感;石榴皮、诃子、黄芩3味蒙药对E. coli综合抑菌效果达极度敏感或高度敏感;在抑制S. aureus的配方中石榴皮、黄芩、诃子可被优先考虑;在抑制E. coli的配方中黄芩、诃子、石榴皮可被优先考虑。     

文心兰新品种‘海文吉祥1号’

文心兰新品种‘海文吉祥1号’是由文心兰‘柠檬绿’（HoneyAngle）组培苗芽变株选育而来。花梗直立坚挺,花瓣和萼瓣淡黄色,唇瓣柱头处呈黄色,向四周边缘逐渐变浅成乳白色。为切花型品种,观赏价值高,应用前景广。     

Development and characterization of a new set of 164 polymorphic EST‐SSR markers for diversity and breeding studies in rubber tree (Hevea brasiliensis Müll. Arg.)

Despite its economic importance and recent genome release, the need for molecular tools for Hevea brasiliensis is high. In the frame of a disease resistance study, EST sequences were retrieved from public database or generated by sequencing SSH libraries. Sequences were trimmed and microsatellite motifs searched using an ad hoc bioinformatic pipeline, and pairs of primers for the amplification of candidate markers were generated. We found a total of 10 499 unigenes from both sources of sequences, and 673 microsatellites motifs were detected using the default parameters of the pipeline. Two hundred sixty‐four primer pairs were tested and 226 (85.6%) successfully amplified. Out of the amplified candidate markers, 164 exhibited polymorphism. Relationships based on dendrograms using simple matching index and diversity statistics based on EST‐SSRs were compared with Genomic SSRs, showing the potentialities of EST‐derived microsatellites for resistance studies but also for population genetics approaches.