Background Data for General Toxicology Parameters in RccHan:WIST Rats at 8, 10, 19 and 32 Weeks of Age     

Okamura T  Suzuki S  Ogawa T  Kobayashi J  Kusuoka O  Hatayama K  Mochizuki M  Hoshiya T  Okazaki S  Tamura K 《Journal of toxicologic pathology》2011,24(4):195-205

Recently, RccHan(TM):WIST (Wistar Hannover) rats were introduced to toxicity studies in Japan. The present study was performed to obtain control data for general toxicological parameters as an aid for interpretation of results in toxicity studies using this strain of rats. Four test groups comprising of 25 male and 25 female RccHan(TM):WIST rats were housed for 2, 4, 13 or 26 weeks from 6 weeks of age and observed and examined for clinical observation, body weight, food consumption, urinalysis, hematology, blood chemistry, organ weight, necropsy and/or histopathology. Ophthalmological examination was not conducted in this study, and the data in this report were obtained from an ongoing 104-week background study in RccHan(TM):WIST rats. These data were compared with the historical control data of CD(SD) (Sprague-Dawley) and/or F344 (Fischer) rats. The body weights of RccHan(TM):WIST rats were lower than those of CD(SD) rats and higher than those of F344 rats. The ophthalmological examination revealed a greater incidence of focal corneal opacity. Histopathology revealed focal mineralization of the cornea and Berlin blue-positive pigmentation in the epididymal interstitium as well as hepatocytes. Other than the above, some minor differences were found in urinalysis, hematology, blood chemistry and organ weights as compared with CD(SD) rats.  相似文献   

A collision tumor consisting of granular cell tumor and adenocarcinoma in the uterus of an aged djungarian hamster     

Golbar HM  Izawa T  Kuwamura M  Okamura K  Fujita D  Tagami Y  Sasai H  Yamate J 《Journal of toxicologic pathology》2011,24(4):233-237

A neoplastic nodular lesion consisting of an admixture of granular cell tumor and adenocarcinoma was found in the uterus of a 26-month-old Djungarian hamster. Neoplastic cells of the uterine adenocarcinoma showed an epithelial nature in their growth patterns and by cytokeratin-immunopositive reaction, exhibiting nuclear pleomorphism. The granular cells had an abundant amount of fine granular eosinophilic cytoplasm and eccentric or central nuclei with no nuclear atypia; the granular structures were positive for periodic acid-Schiff with diastase resistance and were confirmed as lysosomes/autophagosomes by electron microscopy; immunohistochemically, the cells reacted to desmin, vimentin and α-smooth muscle actin and negatively for neurogenic, histiocyte/macrophage or epithelial markers, indicating smooth muscle origin. Because these tumors were generated from different cell origins, a diagnosis of collision tumor was made.  相似文献   

Localization of a novel RNA-binding protein, SKIV2L2, to the nucleus in the round spermatids of mice     

Osman BA  Kawashima A  Tamba M  Satoh E  Kato Y  Iki A  Konishi K  Matsuda M  Okamura N 《The Journal of reproduction and development》2011,57(4):457-467

In our previous study (Kawashima et al., Biol Reprod 2009; 80: 1293-1304), we suggested that the first cycle of spermatogenesis recovered from busulfan-induced temporary arrest was a good model system to analyze the proteins expressed at the specific stages of spermatogenesis in the mouse, and this has been confirmed in the present paper. Namely, six-week-old mice were injected with busulfan at 20 mg/kg body weight. The germ cells except for the undifferentiated spermatogonia disappeared by 32 days after injection. The surviving spermatogonia started to proliferate, and spermatogenesis was entirely recovered about 77 days after injection. By proteome analysis of the busulfan-treated testis during the process of recovery of spermatogenesis, we identified a protein that was expected to be expressed in the spermatogenic cells as Superkiller viralicidic activity-2-like-2 (SKIV2L2). Skiv2l2 mRNA was found in the kidney, epididymis and heart as well as the testis. In the testis, Skiv2l2 mRNA was shown to be highly expressed in the spermatocytes at stages I to VI. On the other hand, SKIV2L2 protein was found to be predominantly localized in the nuclei of round spermatids. In accordance with the fact that SKIV2L2 belongs to the Ski2 family within the superfamily 2 of RNA helicases, it has been shown that SKIV2L2 has both the RNA-binding and ATPase activities.  相似文献   

Molecular mechanisms of the biological clock in cultured fibroblasts   总被引：1，自引：0，他引：1  

Yagita K  Tamanini F  van Der Horst GT  Okamura H 《Science (New York, N.Y.)》2001,292(5515):278-281

In mammals, the central circadian pacemaker resides in the hypothalamic suprachiasmatic nucleus (SCN), but circadian oscillators also exist in peripheral tissues. Here, using wild-type and cryptochrome (mCry)-deficient cell lines derived from mCry mutant mice, we show that the peripheral oscillator in cultured fibroblasts is identical to the oscillator in the SCN in (i) temporal expression profiles of all known clock genes, (ii) the phase of the various mRNA rhythms (i.e., antiphase oscillation of Bmal1 and mPer genes), (iii) the delay between maximum mRNA levels and appearance of nuclear mPER1 and mPER2 protein, (iv) the inability to produce oscillations in the absence of functional mCry genes, and (v) the control of period length by mCRY proteins.  相似文献   

The roles of bone and muscle as phosphorus reservoirs during the sexual maturation of female Japanese eels, Anguilla japonica Temminck and Schlegel (Anguilliformes)     

Y. Yamada  A. Okamura  S. Tanaka  T. Utoh  N. Horie  N. Mikawa  H.P. Oka 《Fish physiology and biochemistry》2001,24(4):327-334

We sought to determine the organs that function as phosphorus (P) reservoirs for supplying this mineral to the ovary during the sexual maturation of the Japanese eel, Anguilla japonica (Anguilliformes). The P content of the ovary increased markedly during sexual maturation despite the lack of an extrinsic P supply (e.g., diet). This phenomenon suggests that the P that accumulated in the ovary was derived from other parts of the eel. In addition, the P content of bone dramatically decreased during maturation, as did the total bone weight. This result suggests that resorption of bone occurred during the sexual maturation of the eel. Whereas the P content and mass of muscle markedly decreased during maturation, the Ca and P contents of the skin (which was scaled) did not. The total (whole-fish) P content was constant throughout maturation. Together, our results suggest that almost all of the P lost from bone and muscle is incorporated in the ovary and that bone and muscle function as P reservoirs during the sexual maturation of the Japanese eel. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Hybrid neurons in a microRNA mutant are putative evolutionary intermediates in insect CO2 sensory systems     

Cayirlioglu P  Kadow IG  Zhan X  Okamura K  Suh GS  Gunning D  Lai EC  Zipursky SL 《Science (New York, N.Y.)》2008,319(5867):1256-1260

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Effect of Gelatin Hydrogel Sheet Containing Basic Fibroblast Growth Factor on Proximal Sesamoid Bone Transverse Fracture Healing in the Horse     

Naoki Sasaki  Satoru Nishii  Kazutaka Yamada  Hidehumi Huruoka  Yasuhiko Tabata 《Journal of Equine Veterinary Science》2013

Our objective in this study was to examine the effect of gelatin hydrogel (GH) sheets containing basic fibroblast growth factor (bFGF) on healing of proximal sesamoid bone transverse fractures in the horse. Ten healthy adult Thoroughbreds were used. The lateral proximal sesamoid bone of the left forelimb and the medial proximal sesamoid bone of the right forelimb were osteotomized, while the horses were under general anesthesia, and subsequently repaired by lag screw fixation using a single 4.5-mm cortical screw. A GH sheet containing 100 μg of bFGF was then sutured to the synovial membrane adjacent to the osteotomized proximal sesamoid bone. In the control group, the fracture was fixed with a lag screw, and the articular capsule was sutured. Fracture healing was assessed by radiographic examination once a week for 16 weeks after the operation. Radiographic examination of bone healing revealed significantly lower demineralization of the fracture line in the GH sheet-treated group than in the control group. The rate of demineralization of the fracture line in the GH sheet-treated group was significantly lower than that in the control group at 2, 4, and 8 weeks after the operation. In this study, we demonstrated that the use of a GH sheet containing bFGF promotes healing of proximal sesamoid bone fracture in the horse. Therefore, it is believed that this treatment strategy would be useful for quick recovery from bone fracture in the horse.  相似文献   

Epidermal structure created by canine hair follicle keratinocytes enriched with bulge cells in a three‐dimensional skin equivalent model in vitro: implications for regenerative therapy of canine epidermis     

Yu Hsuan Wang  Ji Seon Yoon  Ryoko Okamura  Kaori Ide  Manabu Ohyama  Toshio Nishiyama  Toshiroh Iwasaki  Koji Nishifuji 《Veterinary dermatology》2013,24(1):77-e20

Background – Keratinocytes in the hair follicle bulge region have a high proliferative capacity, with characteristics of epithelial stem cells. This cell population might thus be an ideal source for generating the interfollicular epidermis in a canine skin equivalent. Hypothesis/Objectives – This study was designed to determine the ability of canine hair follicle bulge cell‐enriched keratinocytes to construct canine living skin equivalents with interfollicular epidermis in vitro. Animals – Four healthy beagle dogs from a research colony. Methods – Bulge cell‐enriched keratinocytes showing keratin 15 immunoreactivity were isolated from canine hair follicles and cultured on dermal equivalent containing canine fibroblasts. Skin equivalents were subjected to histological, immunohistochemical, western blot and RT‐PCR analyses after 10–14 days of culture at the air–liquid interface. Results – The keratinocyte sheets showed an interfollicular epidermal structure comprising four to five living cell layers covered with a horny layer. Immunoreactivities for keratin 14 and desmoglein 3 were detected in the basal and immediate suprabasilar layers of the epidermis, while keratin 10 and desmoglein 1 occurred in more superficial layers. Claudin 1 immunoreactivity was seen in the suprabasalar layer of the constructed epidermis, and filaggrin monomers and loricrin were detected in the uppermost layer. Basal keratinocytes in the skin equivalent demonstrated immunoreactivity to antibodies against basement membrane zone molecules. Conclusions and clinical importance – A bulge stem cell‐enriched population from canine hair follicles formed interfollicular epidermis within 2 weeks in vitro, and thus represents a promising model for regenerative therapy of canine skin.  相似文献   

The effect of a gelatin β-tricalcium phosphate sponge loaded with mesenchymal stem cells (MSC), bone morphogenic protein-2, and platelet-rich plasma (PRP) on equine articular cartilage defect     

Nao Tsuzuki  Jong-pil Seo  Kazutaka Yamada  Shingo Haneda  Hidefumi Furuoka  Yasuhiko Tabata  Naoki Sasaki 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(6):573-580

We evaluated the curative efficacy of a gelatin β-tricalcium phosphate (β-TCP) sponge loaded with mesenchymal stem cells (MSC), bone morphogenic protein-2 (BMP-2), and platelet-rich plasma (PRP) by insertion into an experimentally induced osteochondral defect. A hole of 10 mm diameter and depth was drilled in the bilateral medial femoral condyles of 7 thoroughbred horses, and into each either a loaded sponge (treatment) or a saline-infused β-TCP sponge (control) was inserted. After 16 weeks, defects were examined by computed tomography, macroscopic analyses, and histological analyses. The median subchondral bone density and macroscopic subscores for joint healing were significantly higher in the treatment legs (P < 0.05). Although there was no significant difference in total histological scores between groups, hyaline cartilaginous tissue was observed across a wider area in the treatment group. Equine joint healing can be enhanced by inserting a BMP-2-, MSC-, and PRP-impregnated β-TCP sponge at the lesion site.  相似文献   

Crossbreeding of a metallic color carnation and diversification of the peculiar coloration by ion-beam irradiation     

Masachika Okamura  Masayoshi Nakayama  Naoyuki Umemoto  Emilio A. Cano  Yoshihiro Hase  Yuzo Nishizaki  Nobuhiro Sasaki  Yoshihiro Ozeki 《Euphytica》2013,191(1):45-56

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