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71.
The cathelicidin family is one of the several families of antimicrobial peptides (AMPs). A bovine myeloid antimicrobial peptide (BMAP‐28) belongs to this family. Recently, the emergence of drug‐resistant bacteria such as methicillin‐resistant Staphylococcus aureus (MRSA) has become a big problem. AMPs are expected to be leading compounds of new antibiotics against drug‐resistant bacteria. In this study, we focused on the activity of BMAP‐28 against bacterial cell surfaces. First, we observed morphological change of MRSA caused by BMAP‐28 using a scanning probe microscope. We also studied activities of BMAP‐28 against adherence of S. aureus to fibronectin, collagen type I, collagen type IV. We confirmed whether BMAP‐28 can bind to lipoteichoic acid (LTA) of S. aureus. BMAP‐28 was indicated as damaging the cell surface of MRSA. In a particular range of concentrations, BMAP‐28 promoted adherence of S. aureus against fibronectin and collagens. It was revealed that BMAP‐28 and LTA of S. aureus bound with each other. Our study showed the potential of BMAP‐28 which can damage MRSA and interact with LTA of S. aureus but promote its adherence in some concentrations. This study provides new points of which to take notice when we use AMPs as medicines.  相似文献   
72.
Monosaccharides such as glucose contribute to the development of meat flavor upon heating via the Maillard reaction; therefore, monosaccharide content is related to beef palatability. Here, we analyzed the effects of genetic and environmental factors on the content of glycogen, one of the precursors of monosaccharides, in the muscles of 958 fattened Japanese Black cattle from Yamagata Prefecture. Analysis of variance showed that muscle glycogen content was affected by the farm and postmortem periods, but not by sex, slaughter age, slaughter month or number of days detained at the slaughter yard. Additionally, consumption of digestible brown rice feed elevated muscle glycogen levels. Glycogen heritability was estimated to be 0.34, and genetic correlations between glycogen and carcass weight (CW) or beef marbling standard (BMS) were weak. The predicted breeding values varied among paternal lines. These results demonstrated that genetic factors might improve muscle glycogen content and therefore beef palatability, but do not influence CW or BMS.  相似文献   
73.
B. E. Ubi    M. Fujimori    M. Ebina  T. Komatsu 《Plant Breeding》2001,120(1):85-87
The amplified fragment length polymorphism (AFLP) technique was applied to detect genetic variation in a sample of 47 plants representing 12 diploid cultivars of rhodesgrass. In this analysis, 50±91 easily scorable fragments could be detected in a single reaction. Each of the individual plants was uniquely identified by a combination of three primer pairs and an 80.2% level of polymorphism was obtained. Large amounts of genetic variation were present within all the cultivars. The results showed that AFLPs could be a robust technique for genome analysis in rhodesgrass with a promising potential as a breeding tool.  相似文献   
74.
Mycoplasma pneumonia of swine (MPS) is caused by Mycoplasma hyopneumoniae (M.hp) and is a common chronic respiratory disease of pigs. Recently, a genetically selected variant of the Landrace pig (Miyagino L2) has a lower incidence of pulmonary MPS lesions. We investigated the pathological and immunological characteristics of MPS resistance in these pigs (n = 24) by comparing with the normal landrace pig (control: n = 24). The pathological MPS lung lesion score in MPS‐selected landrace pigs was significantly lower than in the control. The gene expression of interleukin (IL)‐12p40, which acts as a chemoattractant and a component of the bioactive cytokines IL‐12 and IL‐23, was significantly higher at the hilar lymph nodes, lung, and spleen in MPS‐selected landrace pigs than in control landrace pigs, and these were negatively correlated with the macroscopic MPS lung lesion score. In summary, we demonstrate that resistance against MPS in Miyagino L2 pigs is associated with IL‐12p40 up‐regulation, in comparison with normal landrace pigs without the MPS vaccine. In addition, a comparative study of macroscopic MPS lung lesions and IL‐12p40 gene expression in lung and hilar lymph nodes may lead to beneficial selection traits for the genetic selection for MPS resistance in pigs.  相似文献   
75.
Sleep is one of the essential behaviors in mammalian health and welfare. In this study, we focused on how concentrate‐rich diets (Conc) can influence the sleep of cattle. We hypothesized that Conc would suppress the daily sleep of cows because of behavioral frustration according to shorter eating and rumination. We subjected six Japanese black cows according to crossover experimental design. There were two diet treatments. In the Conc group, 70% of required TDN was supplied by concentrate and 30% by grass silage. On the other hand, in roughage fed group (Rough), all required TDN was supplied by grass silage. Maintenance behaviors, postures of cows, and sleep posture were measured by electronic devices. Cows fed with Conc spent less time in eating and rumination and spent more time in rest than Rough. However, contrary to our hypothesis, cows fed with Conc showed longer daily sleep posture duration (96.2 min/day vs. 69.1 min/day) and more frequent sleep posture bouts (15.4 times/day vs. 11.1 times/day) than Rough. We discussed about following possible explanations why cows fed with Conc slept longer as satisfaction, illness, displacement behavior, and shifting sleep posture.  相似文献   
76.
77.
Helleborus net necrosis virus (HeNNV) in hellebores (Helleborus spp.) has been detected for the first time in Japan. Infected plants had black streaks on fresh leaves and black spots on sepals, which resembled the symptoms of black death disease. The morphology of the virus particles isolated from infected plants was comparable to that of carlaviruses. RT-PCR analysis showed that the entire HeNNV genomic sequence isolated in Japan shared 99% identity with that of HeNNV previously reported in the United States.  相似文献   
78.
Changes in an individual's immune status are considered major contributing factors towards the morbidity of cancer and mortality of aging. To evaluate age-related changes in the immune status of dogs, the immunophenotypes (CD3, CD4, CD8 and CD21) of peripheral blood lymphocytes were measured in 160 healthy dogs aged from 1 to 17 years, and in 365 dogs with various tumors and at various stages. In healthy dogs, the absolute numbers of white blood cells, lymphocytes, and CD3(+), CD4(+) and CD21(+) lymphocytes decreased significantly with age. The relative percentages of lymphocytes and CD4(+) cells decreased significantly, while CD8(+) cells increased significantly with age. The CD4:CD8 ratio showed a significant age-related decrease. In contrast, dogs with tumors possessed significantly lower absolute numbers and relative percentages of all lymphocyte phenotypes, while the CD4:CD8 ratio was significantly higher than in age-matched controls. The relative percentages of CD3(+) and CD8(+) lymphocytes were significantly lower in dogs with distant metastases compared with dogs without metastases, and the CD4:CD8 ratio increased with advanced stage. These observations illustrate the significant changes in immune status with age and the presence of marked immunological defects in a large-scale study of dogs with advanced tumors.  相似文献   
79.
Most global climate change models predict serious ecological and social problems. In Japan, biologists have found climate change is affecting species and ecosystems, including the earlier flowering time of cherry trees which are an important cultural symbol in Japan. Cherry blossom festivals are also important to local economies. This study explored the perceptions of Japanese residents regarding climate change impacts on culturally significant events such as flower timing of cherry trees. We conducted interviews of stakeholders of three cherry blossom festivals, including sixteen organizers of festivals and 26 managers of festival-dependent businesses, to understand their awareness, attitudes and behaviors toward global climate change and impacts on cherry blossom festivals. Most organizers of the festival in Kakunodate were concerned about global warming and its impact on cherry blossom times while organizers of festivals in Nakano and Komoro felt it was unimportant if flower timing affected the festival schedule. Most (92%) managers of festival-dependent businesses mentioned that global warming is occurring and affecting the flower timing of cherry trees, but there were diverse perceptions of global warming impacts on their business. Managers more dependent on income from cherry blossom festivals indicated greater concern for the effects of climate change.  相似文献   
80.
The effect of trypsin on vascular tone and the cytosolic calcium concentration ([Ca(2+)](i)) of endothelial and smooth muscle cells were examined in the rat aorta. A calcium indicator, fura-PE3, was used to measure [Ca(2+)](i) simultaneously with vascular tone. In the endothelium-intact rat aorta, carbachol and trypsin increased [Ca(2+)](i) in a dose-dependent manner. In the endothelium-denuded rat aorta, carbachol did not change [Ca(2+)](i), but trypsin slightly increased it. Addition of trypsin to the norepinephrine-stimulated rat aorta relaxed the muscle with an additional increase in [Ca(2+)](i). Under calcium-free conditions, trypsin induced a transient increase in [Ca(2+)](i). Trypsin-induced endothelium-dependent relaxation was inhibited by preincubation with l-NMMA, an endothelial NO synthase inhibitor, U-73122, a phospholipase C inhibitor, cyclopiazonic acid, a sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase blocker, and lanthanum, a nonselective Ca(2+) channel blocker. However, indomethacin, a nonselective cyclooxygenase inhibitor, and SKF-96365, a store-operated Ca(2+)-channel blocker, had no effect on the trypsin-induced relaxation. These results suggest that trypsin increases [Ca(2+)](i) in the endothelial cells through SKF-96365-insensitive Ca(2+) channels and regulates the release of NO, which results in relaxation of the rat aorta.  相似文献   
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