Spontaneous hormonal variations in male cats following gonadectomy

The increased prevalence of obesity after neutering in cats is problematic in veterinary practice. Although many factors seem to be involved, the role of prolactin (PRL) and insulin-like growth factor-I (IGF-I), both implicated in adipose tissue development and glucose intolerance, should be considered. Seven male cats were castrated when 11 months old. Body weight was then recorded for 56 weeks and PRL, IGF-I and leptin assayed for 44 weeks. Body weight increased steadily but only significantly after 36 weeks. It stabilised after 44 weeks, and the cats then gained about 20% of their initial body weight. IGF-I increased rapidly and was significantly higher by week 3. PRL and leptin increased with initial peaks during the eighth and eleventh weeks, respectively. This study confirms that castration rapidly modifies the hormonal balance, partly explaining the body weight increase, and that hormonal changes precede this body weight increase. Hyperleptinaemia is apparently a consequence of excess weight.     

应用ＥＬＩＳＰＯＴ试验测定重组卡介苗诱导的Ｔ细胞应答

应用免疫磁性分离技术去除免疫小鼠脾脏细胞中ＣＤ４^ 或ＣＤ8^ Ｔ细胞后，在酶免疫斑点试验中证实表达大肠杆菌ＭalE蛋白的重组卡介苗（rBCG.MalE)诱导的Ｔ细胞应答是ＣＤ４^ t细胞依赖的对MalE、PPD持异Ｔ细胞应答的动态分析结果表明，，rBCG.MalE、ＢＣＧ诱导的特异ＣＤ４^ T细胞应答存在Ｔh1/Th2平衡转换现象，即起始阶段为Ｔh1应答，一段时间后出现Ｔh2应答，并逐步形成Ｔh1/Th２混合应答。这些结果，分为枝杆菌Ｔ细胞应答规律提供了新的认识，同时，亦表明ＢＣＧ是优良的外源抗原表达与运送载体。     

Determination of flavonol metabolites in plasma and tissues of rats by HPLC-radiocounting and tandem mass spectrometry following oral ingestion of [2-(14)C]quercetin-4'-glucoside

Epidemiological studies suggest that consumption of flavonol-rich diets decreases the risk of developing heart disease and certain cancers. Recent studies have detected flavonol conjugates in blood and urine following various dietary interventions. To assess to what extent flavonols also accumulate in tissues, where they might be expected to exert anti-carcinogenic and anti-atherogenic effects, [2-(14)C]quercetin-4'-glucoside was synthesized and fed to rats. After 60 min, 93.6% of the ingested radioactivity was recovered from the intestine, incorporated into 18 metabolites that had undergone deglycosylation followed by varying degrees of glucuronidation, methylation, and/or sulfation. [(14)C]Quercetin, the aglycon of the radiolabeled substrate, was present in the intestine and in trace amounts in the liver but was not detected in the plasma and kidneys. The original [2-(14)C]quercetin-4'-glucoside was detected exclusively in the intestine, where it accounted for only 26.2% of the radioactivity. The remainder of the recovered radioactivity was located mainly in the plasma, liver, and kidneys as (14)C-labeled metabolites. However, compared to the quantities in the gastrointestinal tract, the levels of metabolites in plasma and body tissues were very low, indicating only limited absorption into the blood stream. The data demonstrate that quercetin-4'-glucoside, which is a major flavonol in onions, undergoes rapid and extensive metabolism in the intestine, and this appears not to be associated to any extent with transport across the gut wall into the blood stream.     

Variability Of The Cadmium Content In HypericumSpecies Collected In Eastern Austria

In Hypericumspecies some specimens have been found to display higher levels of the toxic heavy metal Cd than the proposed guide value of 0.5mgkg. Plant and soil samples from various regions in Eastern Austria were collected to study the variability in the Cd content of the herbs and relate it to selected soil properties and soil micronutrient contents. The soils contained between 0.01 and 0.44mgkg^?1Cd in the dry soil. Altogether about 7% of the collected plant samples exceeded 0.5mgkg^?1Cd of dry shoots, the proposed guide value for the drug Herba Hyperici. Plants low in Cd were found on sites in the Alpenvorland, the Hainburger Berge, the Eastern Viennese Basin and the Northern Limestone Alps where the levels did not exceed 0.3mgkg^?1Cd of dry shoots. Higher Cd levels in the plants were present in material from the Waldviertel, the Southern Wienerwald and the Semmering region where often bioaccumulation factors for Cd above 1 could be calculated. In these regions the soil pH and carbonate content was somewhat lower than in other regions whereas the soil organic carbon varied greatly. In the Waldviertel some plants from a field were somewhat higher in Cd than nearby plants from the natural vegetation. In a regression analysis, the soil pH, soil organic carbon and soil Cd content were the main factors influencing Cd accumulation in the plant shoots.     

Lablab purpureus (L.) Sweet – diversity, potential use and determination of a core collection of this multi-purpose tropical legume

Two germplasm collections of Lablab purpureus L. Sweet totalling 249 accessions were grown in the field in Australia and Ethiopia and characterised using a common set of morphological and agronomic (M-A) attributes. Data from each site were analysed separately using multi-variate analysis and a classification constructed for each collection. There was considerable diversity within both collections, especially that maintained in Ethiopia. Time to flowering, seed weight, and plant height were the most important attributes in determining group allocation in both classifications. Both collections had a high proportion of L. purpureus subsp. purpureus, especially accessions similar to the Australian cultivars Highworth and Rongai. They also had good representation of the less common L. purpureus subsp. uncinatus Verdc. less common landraces and wild collections from either Africa or India. When combined, the two classifications provided an overview of diversity and highlighted the similarities and dissimilarities between the two collections. The vast range in plant types supported the view that lablab has the capacity to be a multi-purpose legume for both commercial and smallholder agriculture. Some important and less common germplasm identified were Ethiopian domesticated subsp. uncinatus, Ethiopian subsp. purpureus landraces collected from regional markets, semi-domesticated and wild accessions from southern Africa, and wild accessions from India. Using this overview, a core collection of germplasm was selected, which provides researchers with a sound basis for future plant breeding and agronomic studies with this important tropical legume.     

Structure and chemical composition of bast fibers isolated from developing hemp stem

Microscopic and chemical changes of hemp bast fibers were studied during the maturation from vegetative to grain maturity stages at both apical and basal regions of the stems. The content of protein was the main factor related to fiber maturation, whereas increased proportions of mannose and glucose and decreasing levels of galactose were also highly significant. Enhanced glucose deposition in apical fibers could be related to the gradual thickening of the fibers, whereas in basal regions the thickness of the fibers nearly reached the maximum at vegetative stages. In contrast, the extent of lignification remained close to 3-4% during plant growth. Hemp fiber lignins were rich in guaiacyl units and would be rather condensed in nature. In addition, the proportion of p-hydroxyphenyl units displayed a constant decline during maturation. A progressive chemical fractionation of hemp fibers provided further insights to the occurrence and nature of noncellulosic polysaccharides. Notably, these data pointed out that maturation is accompanied by a significant increase in water- and alkali-soluble components containing glucose- and mannose-related polymers and a decrease in arabinose and galactose components disrupted by diluted hydrochloric acid. Taken together, chemical features of the noncellulosic components suggest that the architecture of hemp fibers differs slightly from that of the more widely studied flax fibers.     

Isozyme polymorphism provides fingerprints for germplasm ofArachis glabrata Bentham

Arachis glabrata Bentham, a wild, perennial relative of the cultivated peanut, has been under development as a forage plant for the subtropics and tropics since the early 1960s. To complement the limited genetic resources available in those years, a significant germplasm collection has been assembled in recent years. But little is known about the genetic diversity in this species because research has focused mainly on agronomy. This study aimed to investigate the utility of isozymes for characterisingA. glabrata germplasm. Polyacrylamide gel electrophoresis (PAGE) was applied to rhizome-tip tissue. Isozyme characterisation by PAGE showed a high degree of intraspecific polymorphism for the isozymes α-EST, ACP, GOT, and DIA. When analysed together, the four isozyme systems could clearly distinguish all 15 accessions ofA. glabrata held in the germplasm collection at CIAT. Although several accessions originated from the same region, similarity in isozyme patterns was not correlated with geographic origin. Examining rhizome-tip tissue is useful inA. glabrata, a species which produces few seeds.     

Synthesis and characterization of dehydrogenation polymers in Gluconacetobacter xylinus cellulose and cellulose/pectin composite

To mimic the lignin polymerization process, mats of bacterial cellulose and of a pectin/cellulose composite were used as a host matrix for in vitro polymerization of coniferyl alcohol. A diffusion cell was used to allow the diffusion of both hydrogen peroxide and coniferyl alcohol into the peroxidase impregnated cellulose mats through dialysis membranes. The results indicate that significant polymerization occurs within the mats. The resulting binary and ternary blends were imaged by scanning electron microscopy (SEM) and characterized by chemical means. The presence of pectin induces a better dispersion of the synthetic lignin in the cellulose network and enhances the proportion of alkyl-aryl-ether in the polymer.