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111.
Appearance of albino seedlings caused by plastome-nuclear genome incompatibility was avoided by using polyploid parents in intersubgeneric hybridization between evergreen azaleas and deciduous Rhododendron japonicum f. flavum. Intra- and interploid crosses of 2x or 4x evergreen azaleas with 2xR. japonicum f. flavum showed high capsule set, but their reciprocal crosses failed to set capsules. Green and albino hybrids were obtained from 2x evergreen azaleas × 2xR. japonicum f. flavum crosses where ptDNAs of the green and albino plants were derived from R. japonicum f. flavum (paternal parent) and evergreen azaleas (maternal parents), respectively. All the progenies from the crosses of 4x evergreen azaleas × 2xR. japonicum f. flavum were green triploids with evergreen azalea-specific ptDNA. The efficiency of obtaining green hybrids in interploid crosses was higher than that in intraploid crosses. These results suggest that interploid crosses of 4x evergreen azaleas × 2xR. japonicum f. flavum can overcome plastome-nuclear genome incompatibility between evergreen azalea-specific plastome and the nuclear genome in the resulting hybrid.  相似文献   
112.
Between April 2001 and 2007, 18 Yersinia pseudotuberculosis outbreaks occurred in breeding monkeys at 12 zoological gardens in Japan, and 28 monkeys of 8 species died. A total of 18 Y. pseudotuberculosis strains from the dead monkeys, comprising one strain per outbreak, were examined for serotype and the presence of the virulence genes virF, inv, ypm (ypmA, ypmB and ypmC) and irp2. Of the 18 Y. pseudotuberculosis strains, 7 (38.9%) were serotype 4b, 7 (38.9%) were serotype 1b, and there was one each of serotypes 2b, 3, 6 and 7. All the 18 strains examined harbored virF and inv. Sixteen (88.9%) strains, including the strain of serotype 7, harbored ypmA. However, no strain harbored ypmB, ypmC and irp2.

This study demonstrated that among other pathogenic factors, almost all the Y. pseudotuberculosis isolated from the outbreaks had the ypm gene encoding the superantigenic toxin, YPM. As most of the monkeys who died in those outbreaks originated from South America and other regions, where the presence of the ypm gene have not been reported, YPM might be the cause, or at least the most important factor for, the high mortality of the breeding monkeys infected by Y. pseudotuberculosis in Japan. This is also the first report of a fatal case due to Y. pseudotuberculosis serotype 7 infection in the world.  相似文献   

113.
The effects of interleukin-8 (IL-8) on bovine mammary functions such as milk protein secretion and the blood-milk barrier during mammary involution were evaluated. Following the final milking, recombinant bovine (rb) IL-8 (5 or 25 microg) and a saline placebo were individually infused into the left- and right-front teat cisterns of 6 cows, respectively. Three cows without treatment at the final milking were also used as controls. Mammary secretions and blood were collected at -24, 0, 10, 24, 72, 168, 336, and 720 h after infusion. In the mammary glands infused with 25 microg of rbIL-8, the increases in somatic cell counts and in the concentrations of serum albumin, IgG1 and IgG2, and the decreases in the concentrations of alpha- and beta-casein and beta-lactoglobulin were greater than in the control glands. In the mammary glands infused with 5 microg of rbIL-8, compared to the glands infused with 25 microg of rbIL-8, these changes were moderate. These results indicate that rbIL-8 impairs the integrity of the blood-milk barrier and suppresses milk-specific protein secretions. In the cows infused with 25 microg of rbIL-8, the rectal temperature and serum haptoglobin level were transiently elevated after the infusion, showing that intramammary infusion of rbIL-8 could elicit systemic inflammation.  相似文献   
114.
The influence of genotype imputation using low‐density single nucleotide polymorphism (SNP) marker subsets on the genomic relationship matrix (G matrix), genetic variance explained, and genomic prediction (GP) was investigated for carcass weight and marbling score in Japanese Black fattened steers, using genotype data of approximately 40,000 SNPs. Genotypes were imputed using equally spaced SNP subsets of different densities. Two different linear models were used. The first (model 1) incorporated one G matrix, while the second (model 2) used two different G matrices constructed using the selected and remaining SNPs. When using model 1, the estimated additive genetic variance was always larger when using all SNPs obtained via genotype imputation than when using only equally spaced SNP subsets. The correlations between the genomic estimated breeding values obtained using genotype imputation with at least 3,000 SNPs and those using all available SNPs without imputation were higher than 0.99 for both traits. While additive genetic variance was likely to be partitioned with model 2, it did not enhance the accuracy of GP compared with model 1. These results indicate that genotype imputation using an equally spaced low‐density panel of an appropriate size can be used to produce a cost‐effective, valid GP.  相似文献   
115.
MicroRNAs (miRNA) are small, noncoding RNA molecules consisting of 18 to 25 nucleotides. Malignant melanomas (MMs) are one of the most common malignancies in both dogs and humans. We previously reported that chemically modified synthetic miRNA‐205 (miR‐205BP/S3) inhibits melanoma growth in vitro and in vivo. The present study aimed to evaluate the efficacy of intratumoral administration of synthetic miR‐205 for spontaneous CMMs and to evaluate its potential as systemic therapy. Ten dogs with various stages of MM were treated with miR‐205BP/S3 injected into tumours. Adverse effects (AEs) were assessed in accordance with the Veterinary Cooperative Oncology Group‐Common Terminology Criteria for Adverse Events (VCOG‐CTCAE) v1.1 guidelines. Five cases attained complete remission (CR), three attained stable disease (SD), and two cases displayed characteristics of progressive disease (PD). In all cases, no changes were observed in the blood parameters upon miRNA administration, and miR‐205BP/S3 administration did not yield any side effects. The present results suggest that intratumoral administration of miR‐205BP/S3 is a potentially applicable treatment for canine melanoma.  相似文献   
116.
Zinnia, blue torenia, dahurian patrinia, and scoparia were found to be affected by powdery mildews from 2006 to 2008 in Tokyo. Abundant white, powdery colonies were observed to grow on the stems and leaves of each plant species resulting in chlorosis and eventual dieback of infected leaves and stems. Based on the morphological characteristics of the strain from each plant species, the causal agents were determined to belong to the genus Euoidium and pathogenicity to each original host was confirmed through inoculation experiments. This is the first report of Euoidium infection on these four plant species in Japan.  相似文献   
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119.
This study examined the hypothesis that myostatin and PGC-1α are involved in the increase in skeletal muscle mass and transformation of fiber type in cold-exposed chicks. One-week-old chicks were exposed to acute (24 h) or long-term (8 d) cold at 4 °C or kept warm at 30 °C. Acute cold exposure induced a significant increase in the skeletal muscle weight and the ratio of slow- to fast-fiber specific troponin I expression (sTnI/fTnI), accompanied by a significant decrease in lactate dehydrogenase activity. Expression of myostatin mRNA in the muscle was significantly lower in cold-exposed chicks than in the controls, whereas PGC-1α mRNA expression was significantly enhanced. These changes in the gene expression rapidly returned to the levels of the control chicks after the end of cold exposure, whereas the changes in fiber type and enzymatic activity were not resumed within 24 h after removal of cold exposure. On the other hand, long-term exposure to cold resulted in a remarkable increase in skeletal muscle weight, accompanied by a significant increase in the ratio of sTnI/fTnI and the enzymatic activities of cytochrome oxidase and lactate dehydrogenase. However, the expression level of myostatin mRNA in cold-exposed chicks was not different from that in their age-matched control chicks and that of PGC-1α mRNA was significantly lower than in the controls. These results indicate that myostatin and PGC-1α expression in the skeletal muscle rapidly change in response to acute cold, suggesting the possibility that these two genes could be involved in the increase in muscle mass and transformation of fiber type, respectively, at the initial stage of adaptation in cold-exposed chicks.  相似文献   
120.
Prop-1 acts as an upstream regulator for the Pit-1 gene to induce development of Pit-1 lineage pituitary cell lines, GH-, PRL-, and TSH-producing cells, in the early stage of pituitary organogenesis. Furthermore, Prop-1 is presumed to be involved in the function of FSH/LH-producing cells, gonadotropes, since the defective Prop-1 gene shows hypogonadism. Recently, we reported evidence that Prop-1 directly regulates expression of the porcine FSHbeta gene, thus providing a novel advance in understanding the function of Prop-1 in FSH/LH production and hypogonadism. This study was intended to demonstrate the expressions of Prop-1 gene in pituitary tumor-derived cell lines. RT-PCR analyses were conducted of Pit-1, glycoprotein alpha subunit (alphaGSU), GnRH receptor, and cyclophilin A (a ubiquitously expressing gene). We observed expression of the Pit-1 gene in alphaT1-1, TalphaT1, MtT/S, GH3, and TtT/GF cells, expression of the alphaGSU gene in alphaT1-1, alphaT3-1, LbetaT2, LbetaT4, TalphaT1, and GH3 cells, and expression of GnRH receptor gene in alphaT3-1, LbetaT2, LbetaT4, and GH3 cells, respectively. These expression profiles were in accord with their cell lineages, with only a few exceptions. To accurately measure the expression level of the Prop-1 gene, a quantitative analysis was performed using the real-time PCR method. This analysis demonstrated that the LbetaT2 and LbetaT4 gonadotrope cell lines, which express the FSHbeta gene, express the Prop-1 gene. Taken together with our previous observation that Prop-1 is present in the adult porcine pituitary gonadotropes, Prop-1 might also be involved in development of gonadotropes and hormone production.  相似文献   
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