Effects of growth hormone on female reproductive organs

During the last decade many experiments have been performed to study the effects of growth hormone (GH, somatotropin) on reproductive functions. Most of the studies found only slight or no effects of GH treatment, both on the oestrous cycle and on gonadotropin, progesterone. or oestrogen serum levels. In GH-treated animals, elevated levels of insulin-like growth factor I and GH in the serum could be correlated with an increased number of small (< 5 mm in diameter) ovarian follicles, possibly as a consequence of a reduction of apoptosis and follicular atresia. There is still controversy over the effects of GH on in vivo and in vitro embryo production and on the gestation period. Recent studies produced some evidence that GH-receptor is expressed in ovarian tissue, implying a direct role for GH in the ovary.     

Identification of optimal regions for phylogenetic studies on VP1 gene of foot-and-mouth disease virus: analysis of types A and O Argentinean viruses

An analysis of the informative content of sequence stretches on the foot-and-mouth disease virus (FMDV) VPI gene was applied to two important viral serotypes: A and O. Several sequence regions were identified to allow the reconstruction of phylogenetic trees equivalent to those derived from the whole VPI gene. The optimal informative regions for sequence windows of 150 to 250 nt were predicted between positions 250 and 550 of the gene. The sequences spanning the 250 nt of the 3' end (positions 400 to 650), extensively used for FMDV phylogenetic analyses, showed a lower informative content. In spite of this, the use of sequences from this region allowed the derivation of phylogenetic trees for type A and type O FMDVs which showed topologies similar to those previously reported for the whole VP1 gene. When the sequences determined for viruses isolated in Argentina, between 1990 and 1993, were included in these analyses, the results obtained revealed features of the circulation of type A and type O viruses in the field, in the months that preceded the eradication of the disease in this country. Type A viruses were closely related to an Argentinean vaccine strain, and defined an independent cluster within this serotype. Among the type O viruses analysed, two groups were distinguished; one was closely related to the South American vaccine strains, while the other was grouped with viruses of the O3 subtype. In addition, a detailed phylogeny for type A FMDV is presented.     

A simplified method for measuring dilute emulsion stability

A simple and rapid method for the assessment of the stability of diluted pesticide emulsifiable concentrates has been developed for use in China. It gives results comparable to those obtained with FAO and WHO methods. The importance of some other physical characteristics such as contact angle, surface tension and wetted area in pesticide application are also discussed.     

Digital Image Analysis of Internal Light Spots of Appressoria of Colletotrichum acutatum

ABSTRACT The initial penetration process of appressoria of Colletotrichum acutatum on almond leaves was studied using digital image analysis of light micrographs and scanning electron microscopy. For image analysis, a series of sequential, partially focused digital micrographs of appressoria was analyzed to generate a single, completely focused montage image with a continuous in-focus depth of field. In studies on the development of the internal light spot (ILS), we observed that 50.4% of the appressoria formed an ILS after leaves were inoculated and incubated for 12 h at 20 degrees C, and that this increased to 95.8% after 24 h. Comparative image analyses of appressoria with and without ILSs using depth relief mapping and line profile software options showed that the ILS had a depth relief that was below that of the leaf surface. Depth relief analysis in the ILS region during incubation revealed an increase in depth in this area of up to 1.8 mum in some of the appressoria. A comparative morphological study of the ILS in montage images and the penetration pore of appressoria in scanning electron micrographs showed similar shapes and dimensions of the two structures in the appressorium. Light micrographs of histological sections confirmed fungal penetration and internal vesicle formation in almond leaves within 36 h after inoculation and incubation at 20 degrees C. This study represents the first direct evidence that the ILS in appressoria corresponds to the penetration pore and the developing penetration peg using a rapid, digital image analysis technique.     

Treatment of gastric ulceration in 10 standardbred racehorses with a pectin-lecithin complex

The severity of the erosive and ulcerative lesions of the squamous gastric mucosa in 10 standardbred racehorses in training was classified according to a standard scoring system. Each horse was then treated orally for 30 days with 50 g/100 kg bodyweight daily of a pectin-lecithin complex mixed into the feed. At the end of the period of treatment, the gastric lesions were re-evaluated gastroscopically and the scores were compared with those assigned at the previous evaluation. In three of the horses the gastric ulcerations had healed completely, and in six others the lesions had improved significantly.     

高温应激诱导奶牛乳腺细胞生长周期阻滞

实验通过台盼蓝染色、MTT、细胞流式等方法研究高温(40℃/41℃)对乳腺细胞活性、细胞周期及凋亡的影响。结果表明,高温可以抑制乳腺细胞的增殖,使细胞产生S、G2期阻滞,诱导乳腺细胞凋亡,并随高温强度的增加而作用增强。试验提示高温可诱导乳腺细胞周期阻滞,抑制细胞增殖。