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11.
12.
Rabbit antiserum against hamster ovary was examined on agargel diffusion plates against several hamster tissues, and also against rat and mouse ovarian extracts. Unabsorbed anti-hamster ovary antiserum showed eight to nine precipitin bands for hamster ovary and four to eight bands for other tissue extracts, but no bands against sperm antigens. Anti-hamster ovary antiserum also showed three to four bands for rat and one to two bands for mouse ovarian extracts. The present experiments confirmed previous reports for the hamster and mouse that treatment of eggs with anti-ovary antiserum blocked in vitro fertilization and that the extent of the inhibition was related to the formation of a precipitate on the zone pellucida. A single injection of anti-hamster ovary antiserum inhibited fertilization in mice but not in rats. In vitro fertilization of mouse eggs was also inhibited in the presence of such antiserum.  相似文献   
13.
Solaniol, a Toxic Metabolite of Fusarium solani   总被引:1,自引:6,他引:1  
Fusarium solani M-1-1 isolated from moldy bean hulls produces T-2 toxin, diacetoxyscirpenol, and a new toxic trichothecene, solaniol, in Czapek-Dox-peptone medium.  相似文献   
14.
The present study examined the competence of oocytes from bovine ovaries stored at low temperatures for at least 1 day, which is the necessary time period to complete inspection for bovine spongiform encephalopathy. Storage of ovaries at 10 degrees C for 24 h did not affect oocyte maturation (68% versus 68%) or the potential of oocytes to develop into day 8 blastocysts after in vitro fertilization (25% versus 27%), parthenogenetic activation (19% versus 25%), or somatic cell nucleus transfer (27% versus 32%) compared with controls. In vitro-fertilized and parthenogenetic oocytes from ovaries stored at 10 degrees C for 48 h had a significantly decreased maturation rate and developmental potential, but nucleus-transferred oocytes that received cultured cumulus cells did not (27% versus 32%). Thus, bovine ovaries can be stored at 10 degrees C for at least 24 h without decreasing oocyte maturation competence or the developmental potential of in vitro-fertilized, parthenogenetically activated, and somatic cell nucleus-transferred oocytes, at least to the blastocyst stage. The present study provides valuable information with regard to removing bovine ovaries from abattoirs after testing for bovine spongiform encephalopathy.  相似文献   
15.
Hepatitis C virus (HCV) establishes a chronic infection in 70-80% of infected individuals. Many researchers have examined the effect of human leukocyte antigen (HLA) on viral persistence because of its critical role in the immune response against exposure to HCV, but almost all studies have proven to be inconclusive. To identify genetic risk factors for chronic HCV infection, we analyzed 458,207 single nucleotide polymorphisms (SNPs) in 481 chronic HCV patients and 2,963 controls in a Japanese cohort. Next, we performed a replication study with an independent panel of 4,358 cases and 1,114 controls. We further confirmed the association in 1,379 cases and 25,817 controls. In the GWAS phase, we found 17 SNPs that showed suggestive association (P < 1 × 10-5). After the first replication study, we found one intronic SNP in the HLA-DQ locus associated with chronic HCV infection, and when we combined the two studies, the association reached the level of genome-wide significance. In the second replication study, we again confirmed the association (P combined = 3.59 × 10−16, odds ratio [OR] = 0.79). Subsequent analysis revealed another SNP, rs1130380, with a stronger association (OR=0.72). This nucleotide substitution causes an amino acid substitution (R55P) in the HLA-DQB1 protein specific to the DQB1*03 allele, which is common worldwide. In addition, we confirmed an association with the previously reported IFNL3-IFNL4 locus and propose that the effect of DQB1*03 on HCV persistence might be affected by the IFNL4 polymorphism. Our findings suggest that a common amino acid substitution in HLA-DQB1 affects susceptibility to chronic infection with HCV in the Japanese population and may not be independent of the IFNL4 genotype.  相似文献   
16.
In this study, the level of genetic diversity of captive populations of the itasenpara bitterling (Acheilognathus longipinnis) was assessed to obtain information useful for successful captive breeding and reintroduction; this analysis was performed using mitochondrial DNA (mtDNA) sequence data. Comparison of the captive and wild populations showed low levels of genetic diversity within the captive population and significant genetic differentiation among the captive populations and also between the wild and captive populations, suggesting at chance effect during the founding process for the captive population and a subsequent genetic drift. Therefore, for successful reintroduction, it is important that the reintroduced population reflects all the genetic diversity available from the captive populations, and that releasing a large number of individuals that consist of all captive populations.  相似文献   
17.
A purified extracellular endo β-1,3-xylanase (EC 3.2.1.32) from an isolated strain, Aspergillus terreus A-07, was found to hydrolyze 1,3-xylosyl linkages only. When rhodymenan (β-1,4 and β-1.3-linked xylan) was hydrolyzed by β-1,3-xylanase (EF-6), four β-1,4-linked xylooligosaccharide fractions were produced. The main product was β-1,4-xylotriose, with trace amounts of other β-1,4-linked xylooligosaccharides. Successive degradation by β-l,4-xylosidase of the β,4-xylooligosaccharides that were produced from hydrolysis of β-1,3-xylanase on rhodymenan yielded only xylose as the final product.

We compared the action pattern of this enzyme with that of an extracellular endo β-l,4-xylanase (EC 3.2.1.8) of Streptomyces. From a mixture of products of β-1,4-xylanase hydrolysis on rhodymenan, an isomeric xylotriose was isolated by charcoal chromatography after treating with β-1.4-xylosidase. The structure of this isomeric xylotriose was elucidated by methylation analysis and its susceptibility to β-1,4-xylanase, β-1,3-xylanase, and β-1,4-xylosidase. The obtained isomeric xylotriose was identified as 3-O-β-xylopyranosyl-4-O-β-D-xylopyranosyl-D-xylose (X1→3X1→4X). It has a melting point of 224~225°C and [α]D20(c = 1, H2O)= —46°.  相似文献   
18.
It has been found that although Brevibacterium lactofermentum No. 2256 is incapable of accumulating l-glutamic acid in a biotin sufficient medium, it produces a large quantity of the acid in the presence of sucrose fatty acid ester. In a biotin deficient medium, however, the ester brought the unfavorable diminution of l-glutamic acid accumulation caused by the decrease of glucose consumption in an incubation period. The undesirable effects were practically lost when the ester was added to the culture medium after more than eight hours in the course of incubation. This fact suggests that the ester is concerned with the growth of microorganism. It is very interesting to elucidate the interrelation between sucrose fatty acid ester and biotin. For the maximum accumulation of l-glutamic acid corresponding increase in amount of the ester to the increasing concentration of biotin was necessary. The proportional relation did not extend to excedingly high levels of the two implicating factors. The further observations concerning the effects of the individual fatty acid esters such as sucrose stearate remain unsatisfactory.  相似文献   
19.
This study aimed to detect the most deleterious ROS for goat sperm and then supplemented the extender with a proper antioxidant. For this, 12 adult goats (aged 1–7) were used. Fresh samples were submitted to challenge with different ROS (superoxide anion, hydrogen peroxide, and hydroxyl radical) and malondialdehyde (MDA—toxic product of lipid peroxidation). After experiment 1, sperms were cryopreserved in extenders supplemented to glutathione peroxidase (Control: 0?UI/mL; GPx1: 1?UI/mL; GPx5: 5?UI/mL, and GPx10: 10?UI/mL) and catalase (Control: 0?UI/mL; CAT60: 60?UI/mL; CAT120: 120?UI/mL, and CAT240: 240?UI/mL). Each sample was evaluated by motility, plasma membrane integrity (eosin/nigrosin), acrosome integrity (fast green/rose bengal), sperm morphology, assay of the sperm chromatin structure, mitochondrial activity (3,3-diaminobenzidine), and measurement of lipid peroxidation (thiobarbituric acid reactive substances [TBARS]). It was possible to observe a mitochondrial dysfunction (DAB—Class IV) and low membrane integrity after hydrogen peroxide action. However, the high rates of TBARS were observed on hydroxyl radical. CAT240 presents the lower percentage of plasma membrane integrity. It was possible to attest that hydrogen peroxide and hydroxyl radical are the more harmful for goat sperm. Antioxidant therapy must be improving perhaps using combination between antioxidants.  相似文献   
20.
We report a missense mutation in an adult Japanese patient with acid alpha-glucosidase (GAA) deficiency. A TC to GT transition at nucleotides 1585–1586, was identified. This transition resulted in an amino acid substitution of Ser-529 to Val (S529V) in exon 11. We also have demonstrated that the S529V mutation abolishes the catalytic activity of the enzyme. Our data suggest that this mutation is the cause of the clinical manifestation known as adult-onset GAA deficiency. The missense mutation described here is a new mutation, and the first identified in Japanese patients with GAA deficiency. Received: 23 May 1995  相似文献   
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