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31.
Nationwide seroprevalence of Neospora caninum among dairy cattle in Japan   总被引:3,自引:0,他引:3  
Serum samples from 2420 clinically healthy dairy cattle, randomly selected from stored sera in 18 districts of Japan, were tested for the presence of Neospora caninum antibodies using an indirect fluorescent antibody test (titer > or =1:200). Nationwide seroprevalence is estimated at 5.7% (139/2420). Seropositive cattle were detected in all surveyed districts despite the evidence of confirmed case reports of bovine neosporosis, showing that N. caninum is widely distributed throughout Japan. Age-specific seroprevalence did not increase with cattle age, suggesting that Neospora infection is likely to be transmitted vertically rather than horizontally in Japan. Considering that N. caninum seropositive cows are thought to be more likely to abort, substantial fetal losses may be induced by N. caninum infection in Japan. Devising strategies are needed to reduce the economic impact on the Japanese dairy industry. This is the first study to investigate the nationwide seroprevalence of N. caninum in cattle in Asia.  相似文献   
32.

The spawning area of the Japanese eel is located at the southern part of the West Mariana Ridge in the western North Pacific, but their spawning events have not been observed. To further understand Japanese eel spawning ecology, an interdisciplinary research survey by the R/V NATSUSHIMA (NT14-09, 14 May–4 June 2014) was conducted to detect spawning sites based on the seamount, salinity front, new moon and third quadrant (spawning south of front, west of ridge) hypotheses. Attempts were made to film spawning events with underwater camera systems and to consider if eels might be detected in hydroacoustic observations. Although no Japanese eels or spawning events were video-recorded and no eel aggregations could be clearly identified acoustically, three eggs were collected at two stations in the third quadrant region at or just south of 13° N on 26 and 27 May. Three or four days later, newly hatched preleptocephali were collected at two stations far to the south, including 224 at a station > 160 km southwest of the egg catches, and a few preleptocephali were caught at two stations closer to the egg stations. The eggs and southern preleptocephali were from discrete spawning events, which indicated that at least two spawning sites occurred in May 2014.

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33.
Potato dextrose broth (PDB), one of the most popular culture media for fungi, can be made in the laboratory from potato extract and glucose (handmade PDB) and also bought as powder (commercial PDB). We compared growth of Fusarium oxysporum in handmade and commercial PDBs. For seven strains tested, bud cell formation and fungal biomass were higher in handmade PDB than in commercial PDB. Gel filtration analyses revealed that handmade PDB contained carbohydrates with molecular weights >20 MDa, while most carbohydrates in commercial PDB were <45 kDa. Freshly prepared, raw potato starch had a molecular weight >20 MDa and enhanced bud cell formation by five of seven strains when added to commercial PDB. The addition of glucose to commercial PDB promoted biomass production but not bud cell formation. Furthermore, in a semisynthetic medium containing raw potato starch, bud cell formation was enhanced for all strains tested. These results indicate that the high molecular carbohydrates present in raw potatoes enhanced bud cell formation by Fusarium oxysporum.  相似文献   
34.
Under iron deficient conditions, graminaceous plants secrete mugineic acid family phytosiderophores (MAs) from their roots to dissolve sparingly soluble iron compounds in the rhizosphere, and take up iron in the form of an Fe3+-MAs complex (Takagi 1976). A good correlation has been reported between the tolerance of Fe-deficiency and the amount of secreted MAs (Takagi 1993). Therefore, by using the genes involved in MAs biosynthesis, molecular breeding might produce transgenic plants tolerant to Fe-deficiency with a high level of MAs secretion. The biosynthetic pathway of MAs from L-methionine has been clarified (Fig. 1) and the enzymes participating in this process are now being investigated to isolate the genes responsible. Nicotianamine aminotransferase (NAAT) catalyzes the amino group transfer between nicotianamine (NA) and 2-oxoglutaric acid (Fig. 1). In order to purify NAAT, enzyme assay methods for NAAT have been developed and modified (Shojima et al. 1990; Ohata et al. 1993; Kanazawa et al. 1994). Some characteristics of NAAT have been reported using these enzyme assay methods (Kanazawa et al. 1994, 1995). Here, we further investigate some characteristics of this enzyme to improve the enzyme assay method, namely 1) the effect of K+ and Mg2+ on NAAT activity in vitro, and 2) the direct influence of MAs, Fe3+, and Fe2+ on NAAT activity. In addition, based on these results, the induction of enzyme activity by Fe-deficiency and suppression of the activity by Fe-resupply was investigated, by applying the new enzyme assay method.  相似文献   
35.
Barley contains approximately 10% dietary fiber and is easily cooked with rice, the dominant cereal in Japan, to increase the intake of dietary fiber. This research involved three experiments to examine the influence of barley on blood lipids in human subjects. All subjects received a boiled barley-rice (50/50 w/w mix) supplement two times per day in place of rice for 2 or 4 weeks. In the normolipemic subjects, serum lipids were unaffected by the ingestion of barley for 4 weeks. In twenty hypercholesterolemic men aged 41 ± 5 years, the ingestion of barley was associated with a significant fall in serum total cholesterol, LDL-cholesterol, phospholipids and LDL and VLDL-lipoproteins. In seven mildly hypercholesterolemic women aged 56±7 years, a significant improvement of serum lipid profiles was observed. The present study suggests the possibility that the ingestion of barley-rice could lower serum lipids in hypercholesterolemic subjects.  相似文献   
36.
The effects of vitamin A and vitamin E treatment on superoxide (O2-) production of neutrophils and their intracellular signaling, including intracellular Ca2+, protein kinase C (PKC), and tyrosine kinase (TK), were examined in Holstein calves. After treatment with vitamin A, heat-aggregated IgG (H-agg.IgG)-induced O2- production in neutrophils ranged from 3.7+/-0.4 to 4.3+/-0.9 nmol (mean +/- SD), and it was significantly (P<0.05) higher than that in the control calves. Opsonized zymosan (OPZ)-induced O2- production was similar with that of control calves. Intracellular signaling of neutrophils in vitamin A-treated calves was enhanced compared with that of control calves when stimulated with H-agg. IgG, but not with OPZ. After treatment with vitamin E, H-agg.IgG- and OPZ-induced O2- production of neutrophils ranged from 4.2+/-0.8 nmol to 5.4+/-0.5 nmol and from 7.8+/-0.6 nmol to 8.1+/-0.4 nmol (mean +/- SD), respectively, and they were significantly (P<0.05) higher than those in control calves. Intracellular signaling was also enhanced compared with that of control calves. These results suggested that the effects of vitamin A and E treatment on O2- production were correlated to changes in intracellular signaling of neutrophils in Holstein calves.  相似文献   
37.
A low molecular weight protein was separated from urine samples obtained from a heifer with spontaneous renal disease and from cows with CaNa2EDTA-induced renal dysfunction. The molecular weight and electrophoretic mobility of the separated protein were examined. The low molecular weight protein collected by gel filtration chromatography was further separated into two fractions by ion exchange chromatography using DEAE-cellulose. One of the two fractions, the lowest molecular weight protein showed a single band in SDS-PAGE, and its molecular weight was approximately 12,000. An antiserum against this protein formed a single precipitin line with the urine from cows with experimentally induced renal dysfunction and a heifer with spontaneous renal disease by the double immunodiffusion technique. However, the antiserum did not form any precipitin line with the concentrated urine of healthy cow and human beta 2-microglobulin. In cellulose acetate membrane electrophoresis, this protein migrated in the same position as that of serum gamma-globulin from healthy cow.  相似文献   
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The effect of diminazene aceturate on splenectomized and nonspienectomized dogs with Babesia gibsoni (B. gibsoni) infection was investigated. In splenectomized dogs, the fissional and multiplicational stages of B. gibsoni were observed in peripheral blood films, and hemoglobinuria was frequently observed. These findings were different from previous reports and were not changed by administration of diminazene aceturate. It is clear that the intramuscular administration of diminazene aceturate at the dose of 3 mg/kg body weight for 3 days is not effective against B. gibsoni infection in splenectomized dogs.  相似文献   
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