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1.
Hiroyuki Matsumoto Masahiro Umehara Hironobu Muroi Yoshimasa Yoshitake Shinji Tsuyumu 《Journal of General Plant Pathology》2003,69(3):189-193
Erwinia carotovora subsp. carotovora (Ecc) is a causal agent of soft-rot diseases in a wide variety of plants. Here, we have isolated nonmotile mutants in Ecc
by in vivo insertional mutagenesis using a transposon Tn5. The sequence disrupted by the Tn5 insertion in YMU1 and YMU5 mutants was highly homologous to that of flhC and flhD genes, respectively. They are involved in the initiation of the expression of flagellum-related genes in many gram-negative
bacteria such as Escherichia coli and Salmonella. With electron microscopy, the flhC and the flhD homolog mutants were shown to be aflagellate. Furthermore, the virulence of these mutants was greatly reduced in Chinese
cabbage and potato compared to that of the parental strain. These results suggest that flagellar formation is required for
the pathogenicity of Ecc.
Received: November 5, 2002 / Accepted: December 2, 2002
Acknowledgments This research was supported in part by Grant-in-Aid (12052210) and by a grant from the Ministry of Education, Culture, Sports,
Science, and Technology of Japan (13073). 相似文献
2.
Yoshimasa SASAKI Taketoshi IWATA Masashi UEMA Kenzo YONEMITSU Shizunobu IGIMI Hiroshi ASAKURA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(6):743
Chicken is a major source of human campylobacteriosis. Chicken meat originates not only from broilers but also from spent layers; however, few reports have documented the prevalence and antimicrobial resistance of Campylobacter spp. in layers in Japan. Therefore, we investigated the prevalence and antimicrobial susceptibility of Campylobacter spp. in 47 layer farms in Japan. Fecal samples were collected from the youngest and oldest flocks on the farm, and Campylobacter spp. was isolated from 46/47 (97.9%) farms. Among the C. jejuni isolates, the resistance rates to ampicillin, tetracycline, and ciprofloxacin were 29.6%, 22.2%, and 19.8%, respectively. The ciprofloxacin resistance rate (7.3%) in C. jejuni isolated from old flocks was significantly (P<0.01) lower than that in young flocks (32.5%). 相似文献
3.
Yujia Liu Yuli Qi Qi Wang Fawen Yin Honglei Zhan Han Wang Bingnan Liu Yoshimasa Nakamura Jihui Wang 《Marine drugs》2022,20(6)
Chlorella pyrenoidosa is an excellent source of protein, and in this research, we assessed the antioxidant and emulsifying effects of Chlorella protein hydrolysate (CPH) using neutral proteases and alkaline proteases, as well as the properties of CPH-derived krill oil-in-water (O/W) emulsions. The CPHs exhibited the ability to scavenge several kinds of free radicals, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), O2−, hydroxyl, and ABTS. Additionally, the CPHs (5 mg/mL) scavenged approximately 100% of the DPPH and ABTS. The CPHs showed similar emulsifying activities to Tween 20 and excellent foaming activities (max FS 74%), which helped to stabilize the krill oil-in-water emulsion. Less than 10 mg/mL CPHs was able to form fresh krill oil-in-water emulsions; moreover, the CPHs (5 mg/mL) in a krill O/W emulsion were homogenous, opaque, and stable for at least 30 days. Based on their inhibitory effects on the peroxide value (POV) and thiobarbituric acid reactive substances (TRABS), the CPHs were found to be able to inhibit lipid oxidation in both emulsifying systems and krill O/W emulsions. Thus, the CPHs could improve superoxide dismutase (SOD) activities by 5- or 10-fold and decrease the high reactive oxygen species (ROS) level caused by the addition of H2O2 in vitro. In conclusion, health-promoting CPHs could be applied in krill oil-in-water emulsions as both emulsifiers and antioxidants, which could help to improve the oxidative and physical stability of emulsions. 相似文献
4.
Reona IKEGAMI Yoshimasa TANIMOTO Miori KISHIMOTO Hideshi SHIBATA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):199-202
The rabbit, which is widely used as an experimental animal and is also popular as a companion animal, has a
flat and elongated spleen with the longitudinal hilus running along its visceral surface. The spleen receives
via the hilus an arterial supply that is essential for splenic nutrition and normal functioning. However, the
distribution and variation of the arteries to the spleen have not been studied in detail. This study
investigated anatomical variations of splenic arterial supply in 33 New Zealand White rabbits with a colored
latex injection into arteries. We also examined whether the length of the spleen correlated with the number of
the splenic branches of the splenic artery. The splenic artery always arose as the first independent branch of
the celiac artery and ran along the splenic hilus to usually provide 6 (range, 3 to 10) splenic branches to
the spleen. There was a moderate correlation (R=0.6) between the number of splenic branches
and the longitudinal length of the spleen. The splenic branches often arose as a trunk or trunks in common
with short gastric arteries. The number of common trunk(s) was usually 1 (range, 0 to 4). The data showed that
the pattern and number of arterial branches to the spleen varied according to the individual animal,
suggesting that such variations should be considered when performing experimental and veterinary surgical
treatments in rabbits. 相似文献
5.
Yoshimasa Sugiura Kohji Matsuda Takashi Okamoto Makoto Kakinuma Hideomi Amano 《Fisheries Science》2008,74(1):180-186
To investigate the anti-allergic effects of the brown alga Eisenia arborea. A strain of Brown Norway rats know to strongly respond to immunoglobulin E (IgE) were used as an allergy model animal. The
rats were immunized with ovalbumin by oral administration. The levels of serum IgE and histamine were suppressed in the rats
fed a diet supplemented with dried E. arborea powder. As for the cytokine pattern, the interferon-γ production in the spleens and mesenteric lymph nodes (MLN) was enhanced,
and the interleukin-4 (IL-4) production in the spleens and/or IL-10 production in the spleens and MLN were suppressed. These
results, together with the change in the Th1/Th2 balance, indicate that the rats fed with E. arborea became more anti-allergic, suggesting that E. arborea might possess anti-allergic effects. 相似文献
6.
Sasaki Y Fujisawa T Ogikubo K Ohzono T Ishihara K Takahashi T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(1):129-131
To isolate Campylobacter spp., the feces of healthy cattle, pigs, and broilers were examined between June 1999 and January 2000. Campylobacter lanienae strains were isolated from the feces of healthy pigs, but not from the feces of cattle or broilers. In six C. lanienae isolates, there was only 21-38% DNA-DNA homology to Campylobacter hyointestinalis subsp. lawsonii strain NCTC 12901. Thus, the primary host of C. lanienae is likely to be the pig and C. lanienae appears to be a species distinct from C. hyointestinalis subsp. lawsonii. In addition, an intervening sequence of 226 bp in the 16S rRNA gene was found in four isolates. 相似文献
7.
Periodic signaling controlled by an oscillatory circuit that includes protein kinases ERK2 and PKA 总被引:1,自引:0,他引:1
Maeda M Lu S Shaulsky G Miyazaki Y Kuwayama H Tanaka Y Kuspa A Loomis WF 《Science (New York, N.Y.)》2004,304(5672):875-878
Self-regulating systems often use robust oscillatory circuits. One such system controls the chemotactic signaling mechanism of Dictyostelium, where pulses of adenosine 3',5'-monophosphate (cAMP) are generated with a periodicity of 7 minutes. We have observed spontaneous oscillations in activation of the mitogen-activated protein (MAP) kinase ERK2 that occur in phase with peaks of cAMP, and we show that ERK2 modulates cAMP levels through the phosphodiesterase RegA. Computer modeling and simulations of the underlying circuit faithfully account for the ability of the cells to spontaneously generate periodic pulses during specific stages of development. Similar oscillatory processes may occur in cells of many different species. 相似文献
8.
Nakamura Y Yoshimoto M Murata Y Shimoishi Y Asai Y Park EY Sato K Nakamura Y 《Journal of agricultural and food chemistry》2007,55(11):4407-4413
In the present study, papaya (Carica papaya) seed and edible pulp were carefully separated and then the contents of benzyl isothiocyanate and the corresponding glucosinolate (benzyl glucosinolate, glucotropaeolin) quantified in each part. The papaya seed with myrosinase inactivation contained >1 mmol of benzyl glucosinolate in 100 g of fresh seed. This content is equivalent to that of Karami daikon (the hottest Japanese white radish) or that of cress. The papaya seed extract also showed a very high activity of myrosinase and, without myrosinase inactivation, produced 460 micromol of benzyl isothiocyanate in 100 g of seed. In contrast, papaya pulp contained an undetectable amount of benzyl glucosinolate and showed no significant myrosinase activity. The n-hexane extract of the papaya seed homogenate was highly effective in inhibiting superoxide generation and apoptosis induction in HL-60 cells, the activities of which are comparable to those of authentic benzyl isothiocyanate. 相似文献
9.
Murakami Y Okazaki Y Okayama S Fujihira S Noto T Nakatsuji S Oishi Y 《Journal of toxicologic pathology》2010,23(2):85-89
We report here the interesting case of a 5-year-old male cynomolgus monkey with goblet cell hyperplasia and thickening of the muscular layer throughout the small intestine without exhibiting any clinical symptoms. Necropsy examination showed diffuse thickening of the intestinal wall from the jejunum to the ileum, with an appearance likened to a rubber tube. Histopathologically, marked thickening was observed in both the mucosal and muscular layers in the jejunum and ileum, and slight thickening was observed in the duodenum. Goblet cell hyperplasia with extension of the circular folds and villi was prominently observed. The mucosal surface was covered with a thick mucus layer containing desquamated mucosal epithelial cells, and both the inner and outer muscular layers were markedly thickened due to smooth muscle hypertrophy. Neither macroscopic nor histopathological examination identified any causative factors, such as infection, enteritis and intestinal stenosis, or obstruction that may have caused development of this lesion. Given these observations, this case may simply be considered of spontaneous goblet cell hyperplasia and muscular layer thickening in the small intestine of a cynomolgus monkey. 相似文献
10.
The effect of pretreatment with different doses of GnRH to synchronize follicular wave on superstimulation of follicular growth in dairy cattle 总被引:1,自引:0,他引:1
Sato T Nakada K Uchiyama Y Kimura Y Fujiwara N Sato Y Umeda M Furukawa T 《The Journal of reproduction and development》2005,51(5):573-578
The objective of this study was to evaluate the efficiency of gonadotropin releasing hormone (GnRH) and GnRH doses in synchronizing follicular wave emergence as a pretreatment for superovulation in cattle. Fourteen Holstein-Friesian cows 6 days from estrus were randomly assigned to receive 100 microg (n=4), 50 microg (n=5), or 25 microg (n=5) of GnRH. Superovulation was induced with injections of porcine FSH (pFSH) twice daily, decreasing the dose (total 42 AU) over 5 days beginning 2.5 days after receiving GnRH. On the 7th and 8th injections of pFSH, 750 microg of PGF(2alpha) was also given. With the exception of one cow that was given 50 microg of GnRH, ovulation was induced in all cows from the three groups and the new follicular wave emergence was observed. The total number of follicles for the 25 microg GnRH group was less than that observed for the 100 microg GnRH group (P<0.05), although there were no differences between the 100 microg, 50 microg and 25 microg GnRH groups with respect to the number of preovulatory follicles (>or=10 mm) and CL. The numbers of normal embryos were greater for the 25 microg GnRH group than the 100 or 50 microg GnRH groups (P<0.01); however, the numbers of ova/embryos did not differ significantly between the three groups. These results suggest that 25 microg of GnRH was sufficient to induce ovulation and follicular wave emergence. On day 6 of the estrous cycle, a reduction of the dose of GnRH to synchronize follicular wave emergence as a pretreatment for superstimulation promotes transferable embryos. 相似文献