Cloning and Analysis of 5' Flanking Region of Sporamin A Gene from Sweet Potato

[Objective] The aim of the study is to clone the 5’ flanking region of Sporamin A gene from sweet potato. [Method] The sweet potato "Xushu 18" was used to amplify the 5’ flanking region of Sporamin A gene using specifically designed primers and then target fragment was analyzed by PLACE and PlantCare online. [Result] Besides the conserved elements including TATA-box and CAAT-box,the cis-acting elements including sucrose responsive element CMSRE1,SP8 acting site and some other regulatory sequence such as MYB binding site were also found in Spo A promoter sequence. The results suggest that the promoter has sucrose responsive function.[Conclusion] The study provided reference to reveal the regulation law of Spo A,and to develop high-level expression vectors promoted by Spo A promoter.     

aroA gene PCR-RFLP diversity patterns in Haemophilus parasuis and Actinobacillus species

The Haemophilus parasuis aroA gene encodes 5-enolpyruvylshikimate-3-phosphate synthase and participates in the aromatic amino acids and the folic acid universal metabolic pathway of bacteria. The application of aroA-based PCR-RFLP methodology yields a significant degree of diversity in H. parasuis and Actinobacillus species. PCR amplification of the aroA gene rendered a 1,067-bp fragment in all 15 H. parasuis serovars, and also in Actinobacillus pleuropneumoniae serotypes 1-12, Actinobacillus lignieresii, Actinobacillus equuli, Actinobacillus porcinus, Actinobacillus rossii, Actinobacillus suis, Actinobacillus ureae, Actinobacillus minor and Actinobacillus indolicus. Sau3AI and RsaI digestions of the aroA PCR products rendered seven different restriction fragment length polymorphism (RFLP) patterns: group I (H. parasuis serovars 1, 2, 4-6, and 8-15, A. porcinus and A. ureae), group II (H. parasuis serovars 3 and 7, and A. pleuropneumoniae serotypes 1, 4, 5, 9, 11 and 12), group III (A. lignieresii), group IV (A. pleuropneumoniae serotype 7), group V (A. pleuropneumoniae serotypes 2, 3, 6 and 8, A. equuli, A. rossii, A. minor and A. indolicus), group VI (A. suis) and group VII (A. pleuropneumoniae serotype 10). This is the first report describing the presence of aroA gene in H. parasuis, A. lignieresii, A. porcinus, A. rossii, A. suis, A. ureae, A. minor and A. indolicus and the data presented here demonstrates a significant degree of aroA genetic diversity in H. parasuis and species of the genus Actinobacillus.     

The form of nicotine in tobacco. Thermal transfer of nicotine and nicotine acid salts to nicotine in the gas phase

Thermal transfer to nicotine in the gas phase from neat nicotine, from various nicotine carboxylic acid salts, and from endogenous nicotine in Burley, Bright, and Oriental tobacco samples has been examined by thermogravimetric/differential thermal analysis/mass spectroscopy and evolved gas analysis. Under the conditions used in these studies, the peak transfer temperatures of these substances to nicotine in the gas phase are nicotine and nicotine acetate, both ca. 110-125 degrees C; nicotine malates, ca. 110-210 degrees C for nicotine to malic acid ratios of 1:0.56 and 1:1 and ca. 160-210 degrees C for a nicotine to malic acid ratio of 1:2; (S)-nicotine bis[(2R,3R)-hydrogen tartrate] dihydrate, ca. 195-210 degrees C; and tobacco samples, a range of ca. 160-220 degrees C. These results suggest that nicotine is mostly protonated in tobacco leaf. In all cases, the temperature of the transfer of nicotine to the gas phase was found to be many hundreds of degrees below the temperatures observed around the coal of a burning cigarette (smolder, ca. 500-775 degrees C; dynamic smoking, 600 to over 950 degrees C). Within the narrow zone of a puffing cigarette that encompasses an intermediate temperature range (125-250 degrees C), kinetic data suggest that these temperatures are not sufficient to volatilize significant amounts of nonprotonated nicotine, assuming any exists at all, during the short puff duration (2 s). It is concluded that nonprotonated nicotine and protonated nicotine (salts of nicotine with natural tobacco carboxylic acids) will transfer nicotine to smoke with comparable yields and efficiencies during the smoking process.     

Warming of the Eurasian landmass is making the Arabian Sea more productive

The recent trend of declining winter and spring snow cover over Eurasia is causing a land-ocean thermal gradient that is particularly favorable to stronger southwest (summer) monsoon winds. Since 1997, sea surface winds have been strengthening over the western Arabian Sea. This escalation in the intensity of summer monsoon winds, accompanied by enhanced upwelling and an increase of more than 350% in average summertime phytoplankton biomass along the coast and over 300% offshore, raises the possibility that the current warming trend of the Eurasian landmass is making the Arabian Sea more productive.     

Pyogenic bacterial infections in humans with MyD88 deficiency

MyD88 is a key downstream adapter for most Toll-like receptors (TLRs) and interleukin-1 receptors (IL-1Rs). MyD88 deficiency in mice leads to susceptibility to a broad range of pathogens in experimental settings of infection. We describe a distinct situation in a natural setting of human infection. Nine children with autosomal recessive MyD88 deficiency suffered from life-threatening, often recurrent pyogenic bacterial infections, including invasive pneumococcal disease. However, these patients were otherwise healthy, with normal resistance to other microbes. Their clinical status improved with age, but not due to any cellular leakiness in MyD88 deficiency. The MyD88-dependent TLRs and IL-1Rs are therefore essential for protective immunity to a small number of pyogenic bacteria, but redundant for host defense to most natural infections.     

电导率测定法检测乳中的青霉素G

测定奶中抗生素的存在(含量),对乳品工业十分重要。当前国际上通用的抗生素检测方法已有56种,但测定灵敏度都在0.005IU/ml以上。对于小于0.005IU/ml浓度的检测则无能为力。据报道台湾学者陈成会等发明了一种电导测量的方法,来检测乳中的素霉素G。其根据是抗生素存在时会对脂肪嗜热芽胞杆菌(ATCC10149)的生长产生抑制。用一台微生物分析仪(Maltyus 2000型微生物分析仪)于55     

不孕母牛的人工诱导泌乳

乳牛(含改良牛)在乳品生产中占主导地位。但由于种种原因,可造成一部分牛的不孕而无奶。这是乳牛业中令人头痛的问题。据西北农业大学刘智喜等(1983)对西安地区乳牛产科疾病的调查,在700头适繁母牛中,不孕牛104头,占14.86％,其中疾病性不孕牛69头,占66.35％,原因不明的不孕牛26头,占25％,淘汰牛中不孕牛9头,占8.65％。值得注意的是,在这些不孕牛中,高产牛往往占有较大的比例。由于母牛的不孕,给乳牛场特别是养奶牛专业户造成经济上的重大损失,并使一些很有前途的个体遭到淘汰。因此,对不孕牛进行人工诱导泌乳,具有重要的现实意义。     

胚胎移植在加拿大荷斯坦牛中的应用

序 言 胚胎移植(ET)作为繁育牛的较新方法已被公认和接受。ET是一项过程,通过它在相对短的时间里,从1头母牛能够获得更多的小牛。例如,仅在1年里从1头母牛获得的小牛可能比它整个一生自然生下的小牛还要多。因而,对1头遗传上优秀的母牛使用ET其优越性是十分明显的。 简单地说,这个过程涉及到用激素处理母牛(供体),以便使它在给定的发情周期排出多个卵来(超数排卵)。紧跟这种处理,用供体跟理想公牛配种;大约7天之后,通过一种叫做冲卵的过程从供