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1.
Ochratoxin A contamination of cereal feed grain was monitored during October 1989–September 1990 by analysis of blood samples from slaughter swine in Sweden. The detection of ochratoxin A in swine blood was used as a method to identify swine herds fed ochratoxin A contaminated feed. The contamination level of ochratoxin A in the blood of the positive herds was in the range 2–45 ng/ml with the mean concentration 5.2 ng/ml. Feed samples for mycological analysis were collected from both ochratoxin A positive herds (2 ng/ml blood) and ochratoxin A negative herds (<2 ng/ml blood). From the ochratoxin A positive herds and the ochratoxin A negative herds 22 and 21 feed samples were collected, respectively. No quantitative differences in mould content, as determined by colony forming units, were observed between the two groups. However, there were differences in the mycoflora. The incidence of storage fungi (Penicillium and Aspergillus spp.) was significantly higher (p < 0.05) in feed from ochratoxin A positive herds. Particularly, Penicillium verrucosum was found to be significantly more common (p < 0.001). Altogether 274 isolates were screened for their ability to produce ochratoxin A. Ochratoxin A producers were found only within P. verrucosum; 38% of the 63 isolates produced detectable amounts of ochratoxin A. Ochratoxin A producing isolates of P. verrucosum were found in 60% of the feed samples collected from ochratoxin A positive swine herds and in one sample (5% ) of the feed samples collected from the ochratoxin A negative herds.  相似文献   
2.
The applicability of 2-bromoethyl glycosides in carbohydrate synthesis is demonstrated by the synthesis of glycosides of alpha-L-Fuc-(1----2)-D-Gal and beta-D-Gal-(1----4)-D-GlcNAc. The bromoethyl aglycon was transformed into the methoxycarbonylethylthioethyl spacer, which allowed coupling of the sugars to proteins (BSA and KLH).  相似文献   
3.
The tetrasaccharide, Glc1-6Glc1-4Glc1-4Glc, denoted (Glc)4, is a limit dextrin formed by amylolytic degradation of glycogen. In order to evaluate the possible clinical importance of (Glc)4 excretion as an indicator of certain physiological and pathological conditions, we have developed a new rapid and inexpensive immunoassay using a monoclonal antibody raised against (Glc)4 glycosidically-linked to a carrier protein. As the antibody is highly specific, it can be used to measure native (Glc)4 directly, without the chemical reduction step required in previous methods. A new type of non-equilibrium ELISA inhibition test was developed based on the capacity of free (Glc)4 to decrease initial rates of antibody binding to (Glc)4-coated microtiter wells. The method is highly reproducible and is as sensitive and accurate as the gas chromatography method or radioimmunoassay used previously.Abbreviations (Glc)4 Glc1-6Glc1-4Glc1-4Glc - KLH keyhole limpet hemacyanin - BSA bovine serum albumin - PEG polyethylene glycol  相似文献   
4.
Phenylalanine 4-monooxygenase was purified from bovine liver using a modification of the procedure developed for the rat liver enzyme (Shiman, R., Gray, D. W., and Pater, A. 1979. J. Biol. Chem. 254:11300–11306). The enzyme preparation appeared essentially homogeneous on polyacrylamide gel electrophoresis under non-denaturing conditions. Electrophoresis in the presence of dodecyl sulfate revealed that about 95% of the protein had a mobility, corresponding to Mr=51,000. The remaining 5% was recovered in two minor bands corresponding to Mr of about 35,000 and 15,000 and is likely to result from limited proteolysis of the native enzyme with dissociation of the fragments on denaturation by detergent. The enzyme comigrated with the rat liver enzyme on polyacrylamide gel electrophoresis in both systems studied. No significant difference was observed between the amino acid composition of the bovine and rat liver enzyme, in the reactivity of their sulfhydryl groups or in their iron content (i.e. 1.5–3.0 iron atoms per peptide chain of Mr=50,000). Both enzymes contained less than 0.01 copper atom per peptide chain. The enzymes were inhibited in a similar manner by the chelator bathophenanthroline disulfonate (selective for iron and copper), but not by bathocuproine disulfonate (specific for copper). The results indicate that the bovine and rat liver enzymes are closely similar and that iron, but not copper, is essential for enzyme activity. High performance size-exclusion liquid chromatography revealed that both native enzymes exist in different oligomeric forms, but further studies are required to understand the physicochemical basis for this phenomenon.Abbreviations Bathophenanthroline 4,7-diphenyl-1, 10-phenanthroline - bathocuproine 2,9-dimethyl-4,7-diphenyl-1, 10-phenanthroline - Hepes N-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid - dansyl 1-dimethylaminonaphthalene-5-sulfonyl - DMPH4 2-amino-4-hydroxy-6,7-dimethyl-5,6,7,8-tetrahydropteridine - Mr relative molecular mass  相似文献   
5.
We investigated the class II B genes in free-ranging population of the ring-necked pheasant Phasianus colchicus by a combination of restriction fragment length polymorphism (RFLP), polymerase chain reaction (PCR), and DNA sequencing. Special attention was paid to the variation in the second exon, which encodes the peptide-binding 1-domain. The population was introduced, but it still exhibited major histocompatibility complex polymorphism with at least three segregating class II B haplotypes and consequently six genotypes. We found two class II B genes associated with each haplotype. The class II B genes of birds had until then only been molecularly characterized in the domestic chicken. the pheasant genes were highly variable, although one of the amplified sequences was found in two different haplotypes. Taken together, the most polymorphic positions (residues 37 and 38) were not identical in any of the predicted protein sequences, but all except one of the motifs had already been foud in the domestic chicken. Structurally important features in mammalian class II B genes were generally conserved also in the pheasant sequences, but the loss of a potential salt bridge constituent (Arg72) in several sequences may suggest a slightly different structure of the adjacent parts of the peptide-binding groove. The pheasant genes are most closely related to the so called B-LBII family in the chicken, indicating that this represents a major line of development among avian class II B genes.The nucleotide sequence data reported in this paper have been submitted to the EMBL nucleotide sequence database and have been assigned the accession numbers X75403-X75407. Correspondence to: H. Wittzell, Department of Theoretical Ecology, Ecology Building, Lund University, S-223 62 Lund, Sweden.  相似文献   
6.
Little information exists on mixed-species groups between primates and other mammals in Neotropical forests. In this paper, we describe three such associations observed during an extensive large-vertebrate survey in central Amazonia, Brazil. Mixed-species groups between a primate species and another mammal were observed on seven occasions between squirrel monkeys (Saimiri cf. ustus) and either South American coatis (Nasua nasua) or tayras (Eira barbara) and between brown capuchins (Cebus apella) and coatis. All associations were restricted to floodplain forest during its dry stage. We suggest that the associations involving the coatis are connected to foraging and vigilance but may be induced by a common alternative food resource at a time of food shortage.  相似文献   
7.
The aim of this study was to identify groups of travel mode users, based on objective risk estimates, and examine overall differences in demographic characteristics, perceived risk, worry, perceived control when using travel modes, trust in authorities, and safety motivation. The results were based on a self-completion questionnaire survey about risk perception and travel mode use in a representative sample of the Norwegian public (n = 1864). In addition, aggregate-level data on accidents in transport were used to establish the “objective risk” for various travel modes. The respondents were split into two clusters. The first cluster was characterized by a relatively greater objective risk for accidents related to public travel modes as well as related to being a pedestrian, while the second cluster was characterized by a higher risk level related to motorized private modes of transportation. There was a significant overall difference in the risk estimates among the members of the two clusters. There was also an overall difference in risk perception and other risk-related judgments due to which risk estimate-based cluster the respondents belonged. Associations between objective risk estimates, perceived risk, and worry are discussed in relation to cluster differences in objective risk.  相似文献   
8.

Background

Registered offenders are known to have a higher mortality rate, but given the high proportion of offenders with drug-addiction, particularly among offenders with a custodial sentence, higher mortality is expected. While the level of overall mortality compared to the non-criminal population is of interest in itself, we also estimate the risk of death by criminal records related to substance abuse and other types of criminal acts, and separate between those who receive a prison sentence or not.

Methods

Age-adjusted relative risks of death for 2000–2008 were studied in a population based dataset. Our dataset comprise the total Norwegian population of 2.9 million individuals aged 15–69 years old in 1999, of whom 10% had a criminal record in the 1992–1999 period.

Results

Individuals with a criminal record have twice the relative risk (RR) of death of the control group (non-offenders). Males with a record of use/possession of drugs and a prison record have an 11.9 RR (females, 15.6); males with a drug record but no prison record have a 6.9 RR (females 10.5). Males imprisoned for driving under the influence of substances have a 4.4 RR (females 5.6); males with a record of driving under the influence but no prison sentence have a 3.2 RR (females 6.5). Other male offenders with a prison record have a 2.8 RR (females 3.7); other male offenders with no prison record have a 1.7 RR (females 2.3).

Conclusion

Significantly higher mortality was found for people with a criminal record, also for those without any record of drug use. Mortality is much higher for those convicted of substance-related crimes: more so for drug- than for alcohol-related crimes and for women.  相似文献   
9.
The extent and effect of disease interaction and pathogen exchange between wild and farmed fish populations is an ongoing debate and an area of research that is difficult to explore. The objective of this study was to investigate pathogen transmission between farmed and wild Atlantic salmon (Salmo salar L.) populations in Norway by means of molecular epidemiology. Piscine reovirus (PRV) was selected as the model organism as it is widely distributed in both farmed and wild Atlantic salmon in Norway, and because infection not necessarily will lead to mortality through development of disease. A matrix comprised of PRV protein coding sequences S1, S2 and S4 from wild, hatchery-reared and farmed Atlantic salmon in addition to one sea-trout (Salmo trutta L.) was examined. Phylogenetic analyses based on maximum likelihood and Bayesian inference indicate long distance transport of PRV and exchange of virus between populations. The results are discussed in the context of Atlantic salmon ecology and the structure of the Norwegian salmon industry. We conclude that the lack of a geographical pattern in the phylogenetic trees is caused by extensive exchange of PRV. In addition, the detailed topography of the trees indicates long distance transportation of PRV. Through its size, structure and infection status, the Atlantic salmon farming industry has the capacity to play a central role in both long distance transportation and transmission of pathogens. Despite extensive migration, wild salmon probably play a minor role as they are fewer in numbers, appear at lower densities and are less likely to be infected. An open question is the relationship between the PRV sequences found in marine fish and those originating from salmon.  相似文献   
10.
The objectives of this study were to identify tissue-specific differentially methylated regions (T-DMR’s) in the folate transport genes in placental tissue compared with leukocytes, and from placental tissues obtained from normal infants or with neural tube defects (NTDs). Using pyrosequencing, we developed methylation assays for the CpG islands (CGIs) and the CGI shore regions of the folate receptor α (FOLR1), proton-coupled folate transporter (PCFT) and reduced folate carrier 1 (RFC1) genes. The T-DMRs differed in location for each gene and the difference in methylation ranged between 2 and 54%. A higher T-DMR methylated fraction was associated with a lower mRNA level of the FOLR1 and RFC1 genes. Methylation fractions differed according to RFC1 80G > A genotype in the NTD cases and in leukocytes from subjects with high total plasma homocysteine (tHcy). There were no differences in methylated fraction of folate transporter genes between NTD cases and controls. We suggest that T-DMRs participate in the regulation of expression of the FOLR1 and RFC1 genes, that the RFC1 80G > A polymorphism exerts a gene-nutrition interaction on DNA methylation in the RFC1 gene, and that this interaction appears to be most prominent in NTD-affected births and in subjects with high tHcy concentrations.  相似文献   
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