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1.
Plesiomonas shigelloides is a causal agent of gastroenteritis, sepsis and meningitis in humans. We examined the prevalence of P. shigelloides among great cormorants (Phalacrocorax carbo hanedae) in Japan and the antimicrobial susceptibility of isolates. P. shigelloides was isolated from 33 (47.8%) of 69 fecal samples from great cormorants in 2014. All 33 isolates were subjected to antimicrobial susceptibility testing using broth microdilution methods, which showed resistance to ampicillin (31 isolates, 93.9%), tetracycline (two isolates, 6.1%) and trimethoprim (one isolate, 3.0%). The high prevalence of P. shigelloides in the great cormorants implicates the possible microbiological risk to public health.  相似文献   
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Trunk rot, caused by Fomitiporia torreyae, is one of the most economically important sap rot diseases on Cryptomeria japonica, especially on a cutting cultivar ‘Sanbu-sugi’. This disease had been reported only from Chiba and Ibaraki prefectures in Japan; however, a similar trunk rot on Japanese cedars was found recently in Kyoto prefecture. We identified the causal agent of the trunk rot on Japanese cedars in Kyoto prefecture, clarified the genotype of ‘Sanbu-sugi’ (sensu stricto) using microsatellite markers, and then investigated the relatedness of these infected cedars with ‘Sanbu-sugi’. The pathogen was identified as F. torreyae by its DNA sequences and morphological characteristics of the fruiting body. The 25 ramets of ‘Sanbu-sugi’ had only one genotype based on eight microsatellite loci. Infected Japanese cedars in Kyoto were comprised of different genotypes and showed no close relatedness to ‘Sanbu-sugi’. This is the first report of trunk rot caused by F. torreyae on cultivars of Japanese cedar with no relatedness to ‘Sanbu-sugi’ outside of Chiba and Ibaraki prefectures and showed the potential for expansion of this disease to Japanese cedar plantations in other areas.  相似文献   
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In order to clarify the chronic influence of acid fog on the gas exchange rates of momi fir (Abies firma Sieb. et Zucc.) trees, we exposed them to simulated acid fog (pH 3) for 3 years. The composition of the acid fog was similar to that observed in a region where momi fir trees have been declining, and it contained organic acids. We then treated the firs with various additional stresses, such as drought, low temperature, fine root cutting, ozone exposure, soil acidification, nitrogen load, and rhizosphere aluminum stress. Under chronic exposure to acid fog, the momi fir seedlings exhibited a pattern of stomatal behavior whereby they excessively opened in summer and closed in winter. Furthermore, the stomata of these seedlings tended to open during drought stress, and their needles were visibly injured after ozone exposure. The net photosynthesis rates of the seedlings exposed to acid fog were regulated by their stomatal aperture, rather than directly by acid fog. These results suggest that acid fog exposure disturbs the control of stomatal function in the momi fir seedlings. In addition, we found that chronic acid fog exposure suppressed the decrease in net photosynthesis rate, due to its nitrogen load.  相似文献   
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Genome-wide single nucleotide polymorphism (SNP) markers in Japanese Black cattle enable genomic prediction and verifying parent–offspring relationships. We assessed the performance of opposing homozygotes (OH) for paternity testing in Japanese Black cattle, using SNP genotype information of 50 sires and 3,420 fattened animals, 1,945 of which were fathered by the 50 genotyped sires. The number of OH was counted for each sire–progeny pair in 28,764 SNPs with minor allele frequencies of ≥0.05 in this population. Across all pairs of animals, the number of OH tended to increase as the pedigree-based coefficient of relationship decreased. With a threshold of 288 (1% of SNPs) for paternity testing, most sire–progeny pairs were detected as true relationships. The frequency of Mendelian inconsistencies was 2.4%, reflecting the high accuracy of pedigree information in Japanese Black cattle population. The results indicate the utility of OH for paternity testing in Japanese Black cattle.  相似文献   
5.
ABSTRACT:   The changes in physical habitats and responses of fish, e.g. the Kirikuchi charr Salvelinus leucomaenis japonicus , were examined by placing instream structures in a stream on the upper drainage of the Totsu River system of the Kii Peninsula, Japan, over a two-year period. Instream structures created pools below the structures, and these pools have maintained their functions as fish habitats over two years. In two treatment sections, sections A and B (some red-spotted masu salmon were removed in advance in section B), mean water depth increased soon after placing the structures, but decreased over two years. Mean water velocity slowed after placing the structures in both sections. Total fish abundance has been relatively high at the two treatment sections compared with a control section after placing the structures. Age 1 Kirikuchi charr, however, increased only in section B. These results indicate that instream structures can serve as habitat enhancement for fish, including Kirikuchi charr, in the study area if other appropriate habitat factors for respective species are taken into consideration.  相似文献   
6.
Plasma N-terminal pro-atrial natriuretic peptide (NT-proANP) concentration increases with progression of myxomatous mitral valve disease (MMVD) in dogs. This multicentre, prospective study compared plasma NT-proANP, N-terminal pro-brain natriuretic peptide (NT-proBNP), ANP, and cardiac troponin I (cTnI) concentrations in dogs with MMVD for their characteristics and discriminatory ability to detect cardiac dilatation and congestive heart failure (CHF). Thirty-six healthy dogs and 69 dogs with MMVD were included. Clinical variables were obtained via physical examination, thoracic radiography, and echocardiography. The discriminatory ability of each cardiac biomarker (CB) to determine the presence or absence of cardiac dilatation (event 1) and CHF (event 2) was evaluated using the receiver operating characteristic curves. Plasma NT-proANP, NT-proBNP, and ANP concentrations showed a significant association with the left atrium/aorta ratio (P<0.01). The area under the curve of plasma NT-proANP and NT-proBNP concentrations were 0.72 and 0.75, respectively in event1 and 0.72 and 0.76, respectively in event2. Plasma NT-proANP and NT-proBNP concentrations showed sensitivity 80.0 and 80.0%; specificity 67.6 and 64.7% in event1 (cutoff value; 8,497.81 pg/ml and 1,453.00 pmol/l, respectively) and sensitivity 85.7 and 81.0%; specificity 60.4 and 64.6% in event2 (cutoff value; 8,684.33 pg/ml and 1,772.00 pmol/l, respectively). In dogs with MMVD, plasma NT-proANP, NT-proBNP, and ANP concentrations increase with left atrial enlargement. Particularly, plasma NT-proANP and NT-proBNP concentrations appeared to be equally useful in the discriminatory ability to detect cardiac dilatation and CHF.  相似文献   
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ABSTRACT

Root exudate is derived from plant metabolites and its composition is affected by plant nutrient status. A deficiency of mineral nutrients, such as nitrogen (N) and phosphorus (P), strongly affects the type and amount of plant metabolites. We applied a metabolite profiling technique to investigate root exudates of rice plants under N and P deficiency. Oryza sativa was grown in culture solution containing two N levels (0 and 60 mg N L?1) or two P levels (0 and 8 mg P L?1). Shoot extracts, root extracts, and root exudates were obtained from the rice plants 5 and 15 days after transplanting and their metabolites were determined by capillary electrophoresis/time-of-flight mass spectrometry. Shoot N concentration and dry weight of rice plants grown at ?N level were lower than those of plants grown at +N level. Shoot P concentration and dry weight of rice plants grown at ?P level were lower than those of plants grown at +P level. One hundred and thirty-two, 127, and 98 metabolites were identified in shoot extracts, root extracts, and root exudates, respectively, at the two N levels. One hundred and thirty-two, 128, and 99 metabolites were identified in shoot extracts, root extracts, and root exudates, respectively, at the two P levels. Seventy-seven percent of the metabolites were exuded to the rhizosphere. The concentrations of betaine, gamma-aminobutyric acid, and glutarate in root exudates were higher at both ?N and ?P levels than at their respective high levels. The concentration of spermidine in root exudates was lower at both ?N and ?P levels than at their respective high levels. The concentrations of the other metabolites in root exudates were affected differently by plant N or P status. These results suggest that rice roots actively release many metabolites in response to N and P deficiency.  相似文献   
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