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11.
Kinuko Uno Katsuhiro Miyajima Marika Toma Noriko Suzuki-Kemuriyama Dai Nakae 《Journal of toxicologic pathology》2022,35(2):149
Nonalcoholic steatohepatitis is a lifestyle-related disease and an increasing threat worldwide. Hepatic fibrosis, which results from chronic hepatic diseases including nonalcoholic steatohepatitis, is closely correlated with mortality among hepatic lesions, such as steatosis and inflammation. Thus, it is important to identify factors that can serve as diagnostic and therapeutic targets for hepatic fibrosis. In this study, we examined the function of CD44 in the development of hepatic fibrosis in choline-deficient, methionine-lowered, L-amino-acid diet-fed rats, especially with respect to the proliferation of bile duct epithelium. Male Fischer 344 rats were fed a choline-deficient, methionine-lowered, L-amino-acid diet for 2, 4, 13, or 26 weeks. This diet decreased the body weight; increased the levels of serum parameters indicating liver injury, such as aspartate and alanine aminotransferase; upregulated inflammation- and fibrosis-related gene expression in the liver; and resulted in the development of hepatic lesions, including fatty changes in hepatocytes, inflammatory cell infiltration, and fibrosis. Hepatic hyaluronan was synthesized and deposited in the liver tissue. The expression of both CD44 mRNA and protein was significantly increased throughout the experimental period. CD44 protein was observed in some of the bile duct epithelium, around which hyaluronic acid was deposited, and these bile duct lesions were concordant with the area of hepatic fibrosis. Thus, CD44 expressed in the bile duct epithelium may be a target for controlling nonalcoholic steatohepatitis-related hepatic fibrosis. 相似文献
12.
Spontaneous nonthymic T cell lymphomas in young Wistar rats 总被引：1，自引：0，他引：1
Spontaneous acute lymphomas and related leukemias, occurring in three of 2,974 male Wistar rats used as controls in toxicity studies during the last 14 years (1974-1987), were examined by light and electron microscopy and by using immunohistochemistry. At autopsy, conspicuous hepatosplenomegaly was noted. Morphologically, tumor cells of all three rats were medium-sized lymphocytes with many mitotic figures proliferating mainly in the spleen, liver, and bone marrow. Virus-like particles were not detected. Immunohistochemically, almost all tumor cells were positive for thy-1 antigen but negative for hematopoietic and differentiation markers such as W3/13, W3/25, OX4, OX8, and OX12. The results suggest that the lymphomas in these three rats were derived from T cells. 相似文献
13.
Miyajima R Hasegawa K Yasui Y Kihara T Hosoi M Yamakawa S Iwata H Enomoto M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(4):449-452
The histological characteristics of 9 cases of granular cell tumors (GCTs) observed in B6C3F1 mice were examined to determine their cellular origin. Seven of the 9 cases were found in the uterus and other 2 cases were in the subcutaneous tissue. Tumor cells had abundant granules in the cytoplasm which were stained with PAS and were resistant to diastase treatment. Ultrastructurally, the granules were identified as lysosomes. The cell surface had cytoplasmic processus showing interdigitation with adjacent cells. A character feature of the tumor cells was the presence of a desmosome-like structure on their cell surface but no basal lamina was demonstrated. Although GCTs have been considered to be derived from Schwann cells on the basis of their ultrastructural features and S-100 protein-immunopositive findings, the absence of basal lamina in the present cases may raise a controversy as to their origin. 相似文献
14.
Ai Maeno Yoshimitsu Sakamoto Motoki Hojo Yukie Tada Jin Suzuki Akiko Inomata Takako Moriyasu Akihiko Hirose Noriko Kemuriyama Katsuhiro Miyajima Dai Nakae 《Journal of toxicologic pathology》2021,34(4):353
Zymbal’s gland neoplasms are induced in rats through the administration of various carcinogens, but spontaneous neoplasia is rare. This report describes a spontaneous Zymbal’s gland carcinoma with lung metastasis found in an aged male Fischer 344 rat. Macroscopically, the dome-like tumor nodule, approximately 30 mm in diameter with ulceration, was located near the ear canal of the rat. No healthy tissue or structure of Zymbal’s gland was identified on the corresponding side, while the normal salivary glands and a lacrimal gland were observed. Histologically, a large part of the tumor mass was occupied by poorly differentiated neoplastic cells, the shapes of which were oval to polygonal or fusiform. Additionally, clusters of sebaceous-like foamy cells and squamous metaplasia with prominent keratinization were observed. Tumor cells were found to metastasize to the lung; these cells displayed histological similarities, including a sebaceous gland-like pattern, to those in the primary site. The tumor cells were immunohistochemically positive for cytokeratin AE1/AE3 or vimentin but negative for CD68, S100, α-smooth muscle actin, von Willebrand factor, and desmin. Our results indicate that the tumor was a poorly differentiated Zymbal’s gland carcinoma with lung metastasis. 相似文献
15.
Ayato Kohzu Toshihiro Miyajima Takashi Watanabe Eitaro Wada 《Soil biology & biochemistry》2005,37(9):1598-1607
Factors that affect the δ13C values of fungi need to be analyzed for the progress of isotope-based studies of food-chain or organic matter dynamics in soils. To analyze the factors that control δ13C values of the fungal body, basidiomycete and ascomycete species were grown on a beechwood substrate (six species) and in glucose medium (nine species), and the δ13C value of produced fungal body was compared to that of the carbon source. The 13C enrichment (Δδ13C) in the fungal aggregates compared to the decomposed wood varied from 1.2 to 6.3‰ among six species. In the glucose substrate experiment, the degree of 13C enrichment in the hyphal mat was relatively small and varied from −0.1 to 2.8‰ among nine basidiomycetes species depending on their growth stage. Calculated δ13C values of the respired CO2 were lower than those of the hyphal mat, organic metabolites and the glucose used. The degree of 13C enrichment was affected by fungal species, substrate and growth stage. Fungal internal metabolic processes are the plausible mechanism for the observed isotopic discrimination between fungal bodies and substrates. Especially, dark fixation of ambient CO2 and kinetic isotope fractionation during assimilation and dissimilation reactions could well explain Δδ13C dynamics in our experiments. Through the analysis of field Δδ13C, we could know undisturbed fungal status about starvation, aeration and type of decomposition. 相似文献
16.
Rumiko KODASHIMA Noriharu AE Noriko KIKKOUJI Shingo MATSUMOTO 《Soil Science and Plant Nutrition》2006,52(1):134-134
(pp. 825–831)
This study was carried out to clarify the effects of soil nitrate before cultivation and amounts of basal-dressed nitrogen on additional N application rate and yields of semi-forced tomato for three years from 1998 to 2000. The amounts and timing of additional N dressing were determined based on diagnosis of petiole sap nitrate. The top-dressing was carried out with a liquid fertilizer when the nitrate concentration of a leaflet's petiole sap of leaf beneath fruit which is 2–4 cm declined below 2000 mg L−1 .
For standard yield by the method of fertilizer application based on this condition, no basal-dressed nitrogen was required when soil nitrate before cultivation was 150 mg kg−1 dry soil or higher in the 0–30 cm layer; 38 kg ha−1 of basal-dressed nitrogen, which corresponds to 25% of the standard rate of fertilizer application of Chiba Prefecture, was optimum when soil nitrate before cultivation was 100150 mg kg−1 dry soil; 75 kg ha−1 of basal-dressed nitrogen, which corresponds to 50% of the standard, was optimum when soil nitrate before cultivation was under 100 mg kg−1 dry soil. A standard yield was secured and the rate of nitrogen fertilizer application decreased by 49–76% of the standard by keeping the nitrate concentration of tomato petiole sap between 1000–2000 mg L−1 from early harvest time to topping time under these conditions. 相似文献
This study was carried out to clarify the effects of soil nitrate before cultivation and amounts of basal-dressed nitrogen on additional N application rate and yields of semi-forced tomato for three years from 1998 to 2000. The amounts and timing of additional N dressing were determined based on diagnosis of petiole sap nitrate. The top-dressing was carried out with a liquid fertilizer when the nitrate concentration of a leaflet's petiole sap of leaf beneath fruit which is 2–4 cm declined below 2000 mg L
For standard yield by the method of fertilizer application based on this condition, no basal-dressed nitrogen was required when soil nitrate before cultivation was 150 mg kg
17.
Keiichi Okazaki Kaori Kurimoto Ichirou Miyajima Akira Enami Hitoshi Mizuochi Yasu Matsumoto Hirotaka Ohya 《Euphytica》2005,143(1-2):101-114
Triploid tulips have agronomically desirable traits such as vigorous growth and large flower size, but only a portion of all cultivated tulips is triploid. To apply 2n pollen to polyploid breeding of tulips, the polyploidizing agent, nitrous oxide gas (N2O), was applied to bulbs. In tulips, meiosis in anthers occurs inside the bulbs from mid- to late-October. When meiosis in anthers (excised from bulbs) reached metaphase I, we treated other bulbs of the same clones with N2O for 24–48 h. Most of the treated plants produced pollen grains with a wide-ranging or bimodal size distribution, indicating a mixture of n, 2n and aneuploid pollen grains. The use of pollen containing a relatively high proportion of giant pollen grains tended to yield larger numbers of triploids in the progeny. The number of giant pollen grains could be increased when N2O-treated pollen grains were suspended in 10% sucrose and then sieved through a nylon mesh. Very few polyploids were observed in some cross combinations, even those involving pollen with a relatively high proportion of giant grains. Even so, this low polyploid yield most likely is due to a triploid block, because the capsules obtained in the crosses of the diploid×N2O-treated plants contained some abnormal seeds, which were mostly triploid. Embryo culture was useful in rescuing abnormal embryos. The present study reveals that 2n pollen can be produced at high frequency using N2O during tulip breeding. 相似文献
18.
The structure of ovules that failed to form seeds after compatible pollination in double-flowered zinnias (Zinnia violacea Cav.) was investigated by observing histological sections, and comparing the normal and abnormal development of the seeds. In an embryo sac of zinnia at anthesis, a large nucleus of fused polar nuclei was clearly recognized. Success in double fertilization was determined by the disappearance of this nucleus. In normally developing seeds, the cellular endosperm became vague at 5–6 days after pollination (DAP) and the developing embryos occupied the entire portion of the seeds up to 10 DAP. A number of ovules failed in fertilization for the lack of an embryo sac. In most of the aborted seeds, the embryo sacs degenerated, whereas the aborted embryos were still alive in a small number of aborted seeds. A small percentage of the aborted seeds exhibited an aborted embryo and an unfertilized fused nucleus of two polar nuclei or ‘single fertilization’. The three major problems suggested for the failure in seed formation in pollinated florets of zinnia included failure in fertilization, ovules lacking embryo sacs, and abortion of developing seeds. 相似文献
19.
Takeshi Ohta Yasufumi Toriniwa Naruhiko Ryumon Nobuhiro Inaba Tadaaki Hirao Saori Yamanaka Takayuki Maeno Wakako Sakakibara Morio Sumikawa Kaoru Chiba Akiko Nakamura Katsuhiro Miyajima Fatchiyah Fatchiyah Takahisa Yamada 《Animal Science Journal》2017,88(1):149-155
The onset and progression of type II diabetes is closely related to environmental factors, in particular dietary habit. Moreover, the environmental exposures very early in life can influence the risk for development of type II diabetes later in life. In this study, we investigated pathophysiological changes in the pups of maternal Spontaneously Diabetic Torii (SDT) rats that were fed a high‐fat diet (HFD) throughout gestation and lactation. Maternal SDT rats were continued on HFD for 5 weeks, from day 8 of gestation to day 21 after birth, and biological analyses of the pups were performed from 2 to 22 weeks of age. Results of serum lipid levels in pups from dams fed HFD were higher than pups from dams fed a standard diet, and the onset of diabetes was significantly accelerated in pups from dams fed HFD. In pathological analyses, pups from dams fed HFD showed increases in liver weight and vacuolation of hepatic cells at 2 weeks of age. In conclusion, the metabolic disorder of lipids and glucose in SDT rats is closely related to the nutritional condition of dams during the periods of gestation and lactation. 相似文献
20.
Kemmochi Y Takahashi A Miyajima K Yasui Y Tanoue G Shoda T Kakimoto K 《Journal of toxicologic pathology》2010,23(3):161-164
The present report describes a rare case of spontaneous primary histiocytic sarcoma of the popliteal lymph node in a 19-week-old female Sprague-Dawley (SD) rat. At necropsy, a 10 mm-diameter whitish nodule was found at the site of the femoral muscle in the right hindlimb. Histopathologically, the nodule comprised large pleomorphic histiocyte-like cells with abundant eosinophilic or foamy cytoplasm. Multinucleated giant cells, necrotic foci surrounded by palisading arrays of epithelioid histiocyte-like cells and phagocytosis of cell debris or erythrocytes by the neoplastic cells were occasionally observed. Invasion of the tumor cells into the surrounding adipose tissue was found focally, but there were no distal metastases. Immunohistochemically, the neoplastic cells were positive for vimentin, CD68 (ED1) and lysozyme. We concluded that this tumor occurred in the popliteal lymph node, considering the anatomical location of the lesion and the presence of the remnants of lymphoid tissue involved in the tumor. 相似文献