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61.
Dongowski G Jacobasch G Schmiedl D 《Journal of agricultural and food chemistry》2005,53(23):9257-9267
Microbial metabolism is essential in maintaining a healthy mucosa in the large bowel, preferentially through butyrate specific mechanisms. This system depends on starch supply. Two structurally different resistant starches type 3 (RS3) have been investigated with respect to their resistance to digestion, fermentability, and their effects on the composition and turnover of bile acids in rats. RSA (a mixture of retrograded maltodextrins and branched high molecular weight polymers), which is more resistant than RSB (a retrograded potato starch), increased the rate of fermentation accompanied by a decrease of pH in cecum, colon, and feces. Because they were bound to RS3, less bile acids were reabsorbed, resulting in a higher turnover through the large bowel. Because of the rise of volume, the bile acid level was unchanged and the formation of secondary bile acids was partly suppressed. The results proved a strong relation between RS3, short chain fatty acid production, and microflora. However, butyrate specific benefits are only achieved by an intake of RS3 that result in good fermentation properties, which depend on the kind of the resistant starch structures. 相似文献
62.
Soboll Hussey G Hussey SB Wagner B Horohov DW Van de Walle GR Osterrieder N Goehring LS Rao S Lunn DP 《Veterinary research》2011,42(1):23
ABSTRACT: Equine herpesvirus-1 (EHV-1) infection remains a significant problem despite the widespread use of vaccines. The inability to generate a protective immune response to EHV-1 vaccination or infection is thought to be due to immunomodulatory properties of the virus, and the ORF1 and ORF2 gene products have been hypothesized as potential candidates with immunoregulatory properties. A pony infection study was performed to define immune responses to EHV-1, and to determine if an EHV-1 ORF1/2 deletion mutant (ΔORF1/2) would have different disease and immunoregulatory effects compared to wild type EHV-1 (WT). Infection with either virus led to cytokine responses that coincided with the course of clinical disease, particularly the biphasic pyrexia, which correlates with respiratory disease and viremia, respectively. Similarly, both viruses caused suppression of proliferative T-cell responses on day 7 post infection (pi). The ΔORF1/ORF2 virus caused significantly shorter primary pyrexia and significantly reduced nasal shedding, and an attenuated decrease in PBMC IL-8 as well as increased Tbet responses compared to WT-infected ponies. In conclusion, our findings are (i) that infection of ponies with EHV-1 leads to modulation of immune responses, which are correlated with disease pathogenesis, and (ii) that the ORF1/2 genes are of importance for disease outcome and modulation of cytokine responses. 相似文献
63.
64.
Transgenic crops producing insecticidal toxins from Bacillus thuringiensis (Bt) are widely used for pest control. Bt-resistant insect strains have been studied, but the molecular basis of resistance has remained elusive. Here, we show that disruption of a cadherin-superfamily gene by retrotransposon-mediated insertion was linked to high levels of resistance to the Bt toxin Cry1Ac in the cotton pest Heliothis virescens. Monitoring the early phases of Bt resistance evolution in the field has been viewed as crucial but extremely difficult, especially when resistance is recessive. Our findings enable efficient DNA-based screening for resistant heterozygotes by directly detecting the recessive allele. 相似文献
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66.
Guadalupe Gómez-Hernández Juana Claudia Leyva-Aguilera Sheila Delhumeau-Rivera Georges Seingier Fernando Ricardo Elorriaga-Verplancken Gisela Heckel 《水产资源保护:海洋与淡水生态系统》2021,31(4):841-852
- Marine mammals are indicators of ecosystem health, and thus stranding records are an invaluable information source. The response to marine mammal stranding (RMMS) must be comprehensive, taking into account three components: (i) operations, (ii) research, and (iii) information dissemination. Although RMMS had previously been practised in several coastal locations in Mexico, the recent enforcement of a new regulation for RMMS has posed a challenge to actors as they adapt to it.
- To understand the functioning of RMMS in Mexico, Bahía Todos Santos and Bahía de La Paz, two localities with over 20 years of experience in RMMS, were selected. To achieve this goal, a document review to identify the actors involved and their functions was undertaken together with a social network analysis to identify relevant actors in each locality and semi-structured interviews to identify key topics for RMMS.
- The composition of the involved actors was similar at both locations. Some actors were found to have mandatory functions (i.e. governmental actors), while others (i.e. civil society organizations) performed functions beyond those established in official documents. Governmental agencies, the academic sector, and civil society organizations were the most connected actors and could help disseminate information, facilitate communication within the network, and influence decision-making.
- The main topics identified were, in order of relevance: (i) economic constraints; (ii) actors' involvement; (iii) stranding response logistics; and (iv) recognition among actors.
- In conclusion, several limitations to the RMMS exist at both localities, mainly related to the lack of economic resources, but actors involved in RMMS actions are motivated by their own interests. This study proposes the integration of actors into local networks that take into consideration the biological, physical, and social characteristics of each place.
67.
Summary A potato crop can be grown from true potato seed (TPS) either by transplanting seedlings to the field (seedling transplants)
or by planting tubers derived from seedlings (seedling tubers). The effect of the planting method on performance of TPS families
was evaluated for three types of families, 4x×2x hybrid, open pollinated, and self pollinated. Families from seedling transplants
and seedling tubers and their 4x parental clones were compared for tuber yield and specific gravity. Families from tubers
had substantially higher yields and significantly more uniform specific gravity than families from transplants. Hybrid seedling
tuber families had a higher mean yield than the parental clones and did not differ from them in specific gravity. Selection
in the seedling generation could further improve both OP and hybrid families from transplants and from seedling tubers.
Paper no. 3163 from the Department of Genetics, University of Madison. 相似文献
68.
Coloured potatoes (Solanum tuberosum L.) rich in anthocyanins are gaining increasing interest on the markets, mainly due to beneficial health effects. Potato
varieties containing colour pigments are therefore utilized more and more in actual breeding programmes. In this study, 10
purple-fleshed potato cultivars were compared in their resistance to soft rot caused by Pectobacterium carotovorum (Pc) with 10 white/yellow-fleshed potato cultivars. The results revealed that coloured potato cultivars exhibited on average
better resistance to soft rot than white/yellow-fleshed potato cultivars. On tuber halves of purple-fleshed cultivars, the
extent of rotting caused by Pc was on average 28.6% lower than on white/yellow-fleshed cultivars. The greater resistance of
coloured potatoes coincided with the presence of anthocyanins, higher concentrations of soluble phenols and elevated polyphenol
oxidase activity in tuber tissue. These three components were significantly correlated with the extent of rotting caused by
Pc. However, coloured and white/yellow-fleshed cultivars were not very different in phenylalanine ammonia-lyase and peroxidase
activity. There were also no significant differences in concentrations of dry matter, starch, crude protein and glycoalkaloids.
Key findings reveal that total soluble phenols and anthocyanins contributed crucially to resistance expression in tuber tissue
of coloured potato cultivars. 相似文献
69.
A major aim in sugar beet breeding is to decrease the concentration of soluble N compounds in the beet to avoid negative impacts during beet processing. Due to its importance and analytical limitations the only selection criterion is amino N analyzed in the beet at harvest. It is thus not clear when genotypic differences are established during the season. Furthermore, it is not known whether selection for low amino N affects other N compounds in the beet and the N composition of other plant organs. Therefore, the concentrations of total N and soluble N compounds (protein, amino N, glutamine, betaine, nitrate) were investigated during the season in different organs (leaf blades, petioles, crown, beet) of two sugar beet genotypes differing in the amino N concentration of the beet. Field trials were carried out at three sites in 2002 and in 2003 with harvests at three times from 100 to 170 days after sowing. 相似文献
70.