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41.
Akihiro Hagiwara Norio Imai Yuko Doi Mayuko Suguro Mayumi Kawabe Fumio Furukawa Kasuke Nagano Shoji Fukushima 《Journal of toxicologic pathology》2013,26(4):351-357
The effects of ethyl tertiary-butyl ether (ETBE) on two-stage urinary bladder carcinogenesis in male F344 rats initiated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) were investigated at various dose levels with regard to possible promoting activity. Groups of 30 rats were given drinking water containing 500 ppm BBN, as an initiator, for 4 weeks and starting one week thereafter received ETBE by gavage (daily, 7 days/week) at dose levels of 0 (control), 100, 300, 500 or 1000 mg/kg/day until experimental week 36. No statistically significant differences in incidences of preneoplastic lesions, papillomas, and carcinomas of the urinary bladder were evident in rats treated with 100–1000 mg/kg/day ETBE as compared with control values. Furthermore, the average numbers of preneoplastic or neoplastic lesions per unit length of basement membrane in rats given 100–1000 mg/kg/day ETBE were also comparable to control values. However, papillomatosis of the urinary bladder was found in 4 out of 30 rats (13%) in the group given 1000 mg/kg/day ETBE, and soft stones in the urinary bladder were found in 3 out of these 4 rats. The results thus demonstrated that ETBE did not exert promotional activity on urinary bladder carcinogenesis. However, papillomatosis of the urinary bladder developed in small numbers of the rats given ETBE at 1000 mg/kg/day but not in rats given 500 mg/kg/day or lower doses. 相似文献
42.
Transgenic rice lines that include barley genes have increased tolerance to low iron availability in a calcareous paddy soil 总被引:2,自引:0,他引:2
43.
In vitro and in vivo studies were conducted to evaluate the effects of thiabendazole, mebendazole, levamisole and ivermectin against Gongylonema pulchrum. For in vitro assays, third-stage larvae (L3) incubated with the drugs were administered orally to mice and the ability of larvae to invade the gastric mucosa of the animals was examined. After incubation, only those larvae treated with high concentrations of levamisole (1 and 10 microg/ml) were tightly coiled with intestines exhibiting morphological abnormalities. Good dose-response data for the drugs tested was observed at the time of worm recovery from mice, with no worms recovered at the two highest concentrations of levamisole. In vivo efficacy of the drugs against adult worms was evaluated in six groups of three rabbits, each of which was infected with 30 L3 of G. pulchrum and treated with thiabendazole at 100 mg/kg for 3 days, mebendazole at 70 mg/kg for 3 days, levamisole as a single dose of 8 mg/kg, and subcutaneously injected ivermectin as a single dose of 0.2 mg/kg or vehicles of the drugs (control) at 4 months post-infection. Necropsy 14 days after treatment revealed that levamisole, mebendazole and ivermectin reduced worm burdens by 63.2%, 22.8% and 25.8%, respectively, with no reductions in worms observed with thiabendazole. The surviving worms were principally found in the esophagus with the remainder distributed among the buccal mucosa, the tongue, and/or pharyngeal mucosa in all groups. A number of morphologically abnormal eggs were observed within the uterus and ovijector in female worms recovered from the thiabendazole-treated group. These findings suggest that levamisole exhibits in vivo efficacy against G. pulchrum infection and that the larval invasion tests using mice could be used to screen for anthelmintic susceptibility of nematodes. 相似文献
44.
The in vitro growth inhibitory activities of 15 drugs against Babesia gibsoni were evaluated following establishment of a continuous culture isolate (Aomori isolate). The culture was successfully continued in an RPMI-1640 medium supplemented with 20% normal canine serum or fetal bovine serum in a humidified atmosphere containing 5% CO(2) and 5% O(2) at 37 degrees C. We used this isolate to evaluate the growth inhibitory effect of naphthoquinone (atovaquone), aromatic diamidine (diminazene and pentamidine), artemisinin compounds (artesunate and dihydroartemisinin), an iron chelator (deferoxamine), quinoline-containing compounds (quinine and chloroquine), macrolide antibiotics (azithromycin), lyncomycin antibiotics (clindamycin), tetracycline antibiotics (doxycycline and minocycline), imidazole antifungals (clotrimazole and ketoconazole), and a nitroimidazole antiprotozoal (metronidazole). Atovaquone and aromatic diamidine showed the highest activity; they were followed by artesunate compounds with nanomole levels of IC(50). Metronidazole did not exhibit activity against the parasite. Other drugs exhibited intermediate in vitro activities with micromole levels of IC(50). This is the first report to screen drug activities against B. gibsoni in vitro. The results of our study may support further in vitro drug evaluation for the establishment of therapeutic strategies against canine B. gibsoni infections. 相似文献
45.
Yamato O Hayashi D Satoh H Shoda T Uchida K Nakayama H Sakai H Masegi T Murai A Iida T Hisada H Hisada A Yamasaki M Maede Y Arai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(8):813-818
GM2 gangliosidosis variant 0 (human Sandhoff disease) is a lysosomal storage disease caused by simultaneous deficiencies of acid beta-hexosaminidase (Hex) A and Hex B due to an abnormality of beta-subunit, a common component in these enzyme molecules, which is coded by the HEXB gene. In the present study, a retrospective diagnosis was performed in 2 previous suspected cases of feline Sandhoff-like disease using a DNA test to detect the causative mutation identified previously in 4 cats in 2 other families of Japanese domestic cats. Enzymic analysis was also performed using stored leukocytes and plasma collected from the subject families in order to investigate the usefulness of enzymic diagnosis and genotyping of carriers. The DNA test suggested that the 2 cases were homozygous recessive for the mutation. Consequently, 6 cats homozygous for the same mutation have been found in 4 separate locations of Japan, suggesting that this mutant allele may be spread widely in the Japanese domestic cat populations. In enzymic analysis, Hex A and Hex B activities in leukocytes and plasma measured using 4-methylumbelliferyl N-acetyl-beta-D-glucosaminide as a substrate were negligible in affected cats, compared with those in normal and carrier cats. However, there was a wide overlap in enzyme activity between normal and carrier cats. Therefore, it was concluded that enzymic analysis is useful for diagnosis of affected cats, but is not acceptable for genotyping of carriers. 相似文献
46.
IFN-gamma plays an important role in cellular immunity contributing to microorganism elimination. We have previously reported that bovine colostrum contains high levels of IFN-gamma as well as immunoglobulin. Lymphocytes are potent producers of IFN-gamma, so establishing the lymphocyte population in colostrum will help to identify the source of colostral cytokines. In this study, we used flow cytometric analysis to quantify the population of three types of lymphocytes found in colostrum; namely, CD4 (Th) cells, CD8 (cytotoxic T) cells, and gammadelta-T cells. We also quantified the concentration of colostral IFN-gamma using ELISA. IFN-gamma concentrations were measured in colostrum obtained from 96 healthy Holstein cows; the levels tended to decrease on the first day post-parturition. Flow cytometric analysis showed that many gammadelta-T- and CD8-positive cells were present in the colostrum, and that the CD4/CD8 ratio was low. The ratios of CD8- and gammadelta-T-positive cells to cells of other types decreased during the 5 days after parturition, but that of CD4-positive cells showed no change during the observation period. To identify IFN-gamma-expressing colostral lymphocytes, we used magnetic separation technology to separate the lymphocytes (CD4, CD8 and gammadelta-T) from colostral cells, then examined them for IFN-gamma mRNA expression with real-time PCR (RT-PCR). RT-PCR analysis revealed potent expression of the IFN-gamma gene in CD8-positive cells, reaching higher levels than in CD4- or gammadelta-T-positive cells. These results suggest that the CD8-positive T cells in colostrum play a role as producers of IFN-gamma. 相似文献
47.
Hiromi Kimoto‐Nira 《Animal Science Journal》2018,89(6):835-842
Lactic acid bacteria play an essential role in the food industry in the manufacture of many fermented products (cheese, yogurt, fermented vegetables, etc.). Application of these organisms is now being extended to the area of health improvement, as their probiotic activities become known. Probiotics are defined as viable microorganisms that exert a beneficial effect on the health of the host when they are ingested in sufficient quantity. Lactic acid bacteria and bifidobacteria isolated from the human intestine are the most common probiotics used for human consumption. The development of new probiotics with new beneficial effects is eagerly awaited in the food industry. This review introduces Lactococcus, which are one of the genera of lactic acid bacteria and are mainly isolated from dairy products and fermented vegetables, as new probiotics, focusing especially on Lactococcus lactis H61, which improves skin status in Japanese women with oral intake of heat‐killed or live cells. The deduced mechanisms associated with the beneficial effects of strain H61 are also discussed. 相似文献
48.
With the aim of improving artificial androgenesis in teleost fishes, we tested two methods for producing androgenetic diploids
of amago salmon (Oncorhynchus masou ishikawae), namely, fertilization of gamma-ray irradiated eggs with fused spermatozoa (sperm-fusion method) and the fertilization of
irradiated eggs with untreated sperm followed by the blocking of cell division (mitosis-inhibition method). Our results showed
that the optimal condition for sperm fusion was to treat the sperm with 50% polyethylene glycol (molecular weight 7500) for
100 s. The efficiency of the two methods of androgenesis was compared in terms of fertilization rate, hatching rate, and larval
survival after hatching. The rate of fertilization was lower with the sperm-fusion method than with the mitosis-inhibition
method, but the reverse was true for the hatching rate. The survival rate of hatched larvae was the same with the two methods.
Androgenesis was confirmed with a recessive albino color marker, and all viable offspring were found to be heterozygous based
on analysis of the microsatellite markers. Our results suggest that androgenesis with the sperm-fusion method is a promising
approach with potential applications in both aquaculture breeding programs and the preservation of endangered freshwater fishes. 相似文献
49.
Kim Hee-Jin Ohtani Masataka Kakumu Akira Sakakura Yoshitaka Hagiwara Atsushi 《Fisheries Science》2020,86(4):655-663
Fisheries Science - There are two types of movement pattern in the Brachionidae (rotifers), swimming and attachment, although the factors that induce a shift between them have not been adequately... 相似文献
50.
The red alga Kappaphycus alvarezii is economically important as an edible species and as a source of carrageenan, and has been extensively cultivated in many
tropical countries. For this species, different color strains, which differ from each another in growth rate and carrageenan
content, have been reported for decades. In this study, lectins from brown, red, and green strains of K. alvarezii cultivated in Vietnam were isolated and characterized for evaluation of their biochemical properties and contents. The results
showed that each color strain contained in common the three lectins, named KAA-1, KAA-2, and KAA-3, which shared the hapten-inhibition
profile of hemagglutination, 20 N-terminal amino acid sequence, and equivalent molecular mass within a range of 28,016 ± 1.2
to 28,021 ± 1.8 Da, but differed in their yields, with the highest yield of KAA-2. These properties of the three isolectins
were also comparable among the three different color strains. However, the sum of the yields of the three isolectins decreased
in the order: red (21.4 mg) to green (15.9 mg) to brown strains (15.1 mg), from 500 g fresh alga. Thus, this algal species
can be a good source of useful lectins, irrespective of color strain. 相似文献