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31.
Nivalenol (NIV) is a trichothecene mycotoxin produced by Fusarium fungi that frequently contaminates agricultural commodities. Dietary administration of NIV to adult mice affects the renal glomeruli, but data about NIV toxicity in human infants are limited. To evaluate the effects of NIV on infant kidneys, 3-week-old male ICR-derived glomerulonephritis (ICGN) and ICR mice were administered 0, 4, 8 or 16 ppm NIV in diet for 4 weeks, and their renal status was compared with age-matched or adult ICR mice. In ICGN mice, the number of glomeruli showing mesangial expansion and α-smooth muscle actin (SMA)-positive mesangial cells was higher with 16 ppm NIV compared with controls. No other significant differences were observed in ICGN mice. In infant ICR mice, the IgA serum concentrations were significantly elevated without glomerular morphological changes in the 16 ppm NIV group. There was no difference in NIV sensitivity in the kidneys of infant ICGN and ICR mice. These data suggest that the kidneys in infant mice are not sensitive to nivalenol under the present conditions.  相似文献   
32.
Field isolates of BVDV which do not show the exaltation of Newcastle disease virus (END) phenomenon (END) are rarely reported. In this study, 45 BVDV field isolates from cattle in Hokkaido prefecture in Japan were analyzed by the reverse plaque formation method, the END method and observation of cytopathic effects. END virus was detected in 34 of 45 isolates (75.6%), although 35 of 45 field isolates contained END phenomenon positive virus as the predominant virus population. We propose that END viruses are widely distributed in the field and that it is possible that the mixture of biologically distinct BVDV correlates with the appearance of disease in infected animals.  相似文献   
33.
The recurrence of reduced milk flow is a common sequela after placement of teat inserts in the streak canal as a treatment for teat injury. We evaluated the effects of three types of commercial teat inserts on wound healing. Thirty-two normal streak canals of eight cows were incised longitudinally using a teat knife. Then, a wax-bougie, silicone self-retaining cannula, and catgut teat dilator were placed in each cow for 7 days. No insert was placed on the remaining teat as a control. Histopathological examination revealed that granulation polyps with squamous metaplasia developed in the area around the rosette of Furstenberg in most teats in which silicone cannulas and catgut teat dilators were placed, whereas the controls and the teats with wax-bougies healed with less tissue reaction. This study suggests that the placement of irritating inserts, such as a silicone cannula and catgut teat dilator, interfere with wound healing.  相似文献   
34.
Previously, we reported that rhizome powder of Kaempferia parviflora Wall. Ex. Baker prevented obesity and a range of metabolic diseases. In this study, to clarify which molecular mechanisms and active ingredients of K. parviflora have an anti-obesity effect, we investigated the effect of ethyl acetate extract of K. parviflora (KPE) on TSOD mice, a spontaneously obese Type II diabetes model, and on pancreatic lipase. In the TSOD groups, KPE showed a suppressive effect on body weight increase and visceral fat accumulation and also showed preventive effects on symptoms related to insulin resistance, hypertension and fatty liver. In addition, KPE also suppressed body weight increase and food intake in TSNO mice groups, which served as reference animals, at an early stage of administration. Searching for the ingredients in KPE revealed that KPE contains at least 12 kinds of polymethoxyflavonoid (PMF). Furthermore, KPE and its component PMFs showed an inhibitory effect on pancreatic lipase. The above results suggest that KPE has a preventive effect on obesity and various metabolic diseases. The mechanisms of action probably involve inhibition of pancreatic lipase by the PMFs in KPE.  相似文献   
35.
Glucocorticoid (GC) administration with or without other chemotherapeutic reagents is a commonly used option in the treatment of mast cell malignancies. However, the responsiveness of mast cell tumors to GC treatment varies in individuals, and the regulatory mechanisms determining the GC sensitivity of malignant mast cells remain unclear. Since the expression of the GC receptor (GR) has been reported to be associated with GC sensitivity in human neoplastic lymphocytes, we attempted to investigate the relationship between GR levels and GC sensitivity by using neoplastic mast cells derived from canine mast cell tumors (MCTs). To elucidate the regulatory mechanisms involved in GC responsiveness, we analyzed various canine MCT cell lines and tissue samples from dogs with MCT. While the proliferation of canine MCT cells was suppressed by the addition of GC to the culture, we found that MCT cells derived from humans and rodents, as well as canine lymphoma cells, responded poorly to GC. However, there were also some variations in responsiveness to GC treatment among canine MCT cell lines used in this study. Using real-time polymerase chain reaction and Western blot analysis, we elucidated the relationship between GR expression and responsiveness to GC in canine MCT cells. Furthermore, to assess the involvement of GR expression in GC sensitivity in vivo, clinical investigations were conducted on dogs with cutaneous MCT. Written informed consent was obtained from owners, and the affected dogs were treated with prednisolone (0.5-2.0 mg kg(-1)day(-1), administered orally) 1 or 2 weeks prior to the surgical removal of the tumors. Tumor volume was measured according to WHO criteria both before and after prednisolone treatment, and the GC sensitivity of each MCT was determined on the basis of the reduction in tumor volume. Of the 15 dogs with MCT, 11 responded to treatment with prednisolone completely or partially, whereas 4 dogs showed no response. Examination of clinical samples obtained by surgical removal revealed that GR expression levels were significantly lower in GC-resistant MCT tissues than in GC-sensitive MCT tissues. Thus, these results strongly indicate that GR expression may contribute to GC sensitivity in canine MCT.  相似文献   
36.
Pancreatitis is a common exocrine pancreatic disease in dogs, and the pancreatic lipase immunoreactivity (PLI) test is used for diagnosis. Enzyme catalytic assay is thought to have low specificity, but a lipase activity assay with increased specificity has been developed in human clinical chemistry. We measured serum lipase activity of 65 client-owned dogs using the newly developed FUJI DRI-CHEM slide and compared the results with their PLI concentrations. The results showed a good correlation (r = 0.91), and the normal and pancreatitis dogs identified based on the PLI values were correctly separated based on lipase activity. The present study suggests that FUJI DRI-CHEM lipase activity would be helpful for diagnosis of pacreatitis in dogs and, in particular, that it can be used as a patient-side assay and contributes to immediate treatment.  相似文献   
37.
Cultivation of useful terrestrial and aquatic plant species in plant bed filter ditches enables to treat domestic wastewater in addition to resource recycling and amenity functions. We reported previously that a ditch planted with papyrus removed Nand P most effectively from artificial wastewater. We evaluated the effectiveness of plant bed filter ditches in the treatment of eutrophic pond water, which unlike artificial wastewater, contains particulate Nand P. Experimental ditches were planted with papyrus, African marigold, peppermint, and impatience. These plant species were effective in removing N and P from artificial wastewater and could be used by rural communities for the production of handicrafts, cut flowers, and ornamental purposes. The control ditch did not contain plants (plant-free ditch). Pond water was continuously supplied to the ditches at a loading rate of 0.6–0.9 g m-2 d-1 for Nand 0.2–0.35 g m-2 d-1 for P. In the plant-free ditch, particulate Nand P in the influent were removed by passage through the bed filter, unlike NO3-N and PO4-P. A larger amount of PO4-P was dissolved from particulate P in the bed filter. The planted ditches effectively removed NO3-N, PO4-P as well as particulate Nand P. The planted ditches were able to purify eutrophic pond water, resulting in clear water with a concentration below 0.3 mg L-1 for N and 0.02 mg L-1 for P, concentrations at which water bloom does not occur. The average removal rate of pollutants by the planted ditches during the experiment, except for the first 2 weeks, was 0.67 g m-2 d-1 for total N and 0.03 g m-2 d-1 for total P. We recommend that plant bed filter ditches containing papyrus and flowers be used for ornamental purposes and removal of N and P from pond water along with the supply of clear water as ornamental streams.  相似文献   
38.
Different microbial communities characterized by the Biolog pattern were developed in the rhizosphere of radish grown on a rockwool hydroponic system treated with chloropicrinfumigated and non-fumigated soil suspensions although no differences were observed in their viable counts. Different microbial communities also were developed in the rhizosphere and non-rhizosphere. After the development of microbial communities in the rhizosphere, bud cells of Fusarium oxysporum that causes vascular wilt of radish plants were inoculated, and disease symptoms were examined. Treatment with the non-fumigated soil suspension was much more effective than that with the fumigated one in controlling the disease, indicating that the Biolog method might be applicable to characterize microbial communities that control the disease caused by F. oxysporum.  相似文献   
39.
The common marmoset (Callithrix jacchus) is now widely used in various research fields, including toxicology. However, information about the background pathology of this species is scarce. Here, we report a case of rhabdomyosarcoma that spontaneously occurred in a common marmoset. A 44-month-old male common marmoset was euthanized due to bilateral hind limb paralysis. At necropsy, a 2×2×5-cm intramuscular mass was observed in the lower right back. Histologically, the mass was mainly composed of interlacing bundles of spindle-shaped tumor cells. Immunohistochemically, the tumor cells were positive for myogenin, desmin, vimentin and alpha-smooth muscle actin. Ultrastructurally, the tumor cells contained bundles of myofilaments with Z-band-like structures. Thus, the tumor was diagnosed as a rhabdomyosarcoma. To our knowledge, this is the first report of spontaneous rhabdomyosarcoma that was definitely diagnosed in the common marmoset.  相似文献   
40.
Based on sequences of two cosmid clones from Japanese quail (Coturnix japonica, Coja), we confirmed that the syntenic cluster, GNB2L1~BTN1~BTN2, is located in the quail TRIM subregion of the quail major histocompatibility complex (MHC Coja) region. These cosmids also included four CjBG loci and one CjLEC locus; therefore, the quail TRIM subregion was thought to be adjacent to the BG/LEC subregion. We then identified three polymorphic markers – CjHEP21, CjTRIM39.2 and CjBTN2 – in the TRIM subregion that may be useful for the functional analysis of the MHC‐Coja region. We examined MHC‐Coja sequences from 321 individual quails sampled from 11 inbred strains, and we found eight alleles for each of the three genes – CjHEP21, CjTRIM39.2 and CjBTN2. These polymorphisms represent the first avian DNA markers in the TRIM subregion. Additionally, we discovered a quail‐specific VNTR (variable number of long tandem repeats, 133–137 bp) in intron 7 of CjBTN2. We identified 25 haplotypes in the sample of 321 quail; these haplotypes comprised combinations of all 24 alleles of the three polymorphic genes. We suggest that there are two recombination hotspots, one between each pair of adjacent loci. All strains, except AMRP, contained multiple haplotypes; the AMRP strain contained a single, apparently fixed haplotype.  相似文献   
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