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41.
Kayoko Kudo Toru Hoshiya Tomomi Nakazawa Tsubasa Saito Natsumi Shimoyama Isamu Suzuki Kazutoshi Tamura John Curtis Seely 《Journal of toxicologic pathology》2012,25(4):277-280
Spontaneous renal tubule tumors (RTTs), with a distinctive morphological phenotype, were
present in three Sprague-Dawley rats, 1 male and 2 females, out a total of 120 animals of each
sex from untreated and placebo control groups in a 2-year carcinogenicity study. One female had
one carcinoma, adenoma and hyperplasia, and the other female had five adenomas and many
hyperplastic lesions; the male case had one carcinoma. From these cases, a biological continuum
of hyperplasia, adenoma and carcinoma could be recognized. The tumors were present in the renal
cortex and appeared as solid lobulated growths with occasional central necrosis. The lobules
were divided by a small amount of fibrovascular tissue. Occasionally the larger tumors
contained a cystic area. Tumor cells appeared distinctive and exhibited variable amounts of
eosinophilic/amphophilic and vacuolated cytoplasm. Nuclei were round to oval with a prominent
nucleolus. Mitotic figures were uncommon, and no distant metastasis was noted. The tumors were
seen as multiple and bilateral lesions in two animals and had no apparent relationship to
chronic progressive nephropathy (CPN). Foci of tubule hyperplasia were also noted to contain
the same type of cellular morphology. The morphological and biological features of these 3
cases resembled the amphophilic-vacuolar (AV) variant of RTT that has been posited to be of
familial origin. This is a report of spontaneous familial renal tumors in Sprague-Dawley rats
from Japan. 相似文献
42.
Noji N Nakamura T Kitahata N Taguchi K Kudo T Yoshida S Tsujimoto M Sugiyama T Asami T 《Journal of agricultural and food chemistry》2007,55(18):7258-7263
Pyrroloquinoline quinone (PQQ) is believed to be an important factor for mammalian growth and development and has, therefore, been declared a vitamin by some researchers. However, this issue remains controversial, and from a nutritional viewpoint, accurate determination of PQQ levels in a variety of foods is very important. Here, we describe a simple, highly sensitive, and highly selective method for quantitative analysis of PQQ. Liquid foods or aqueous extracts of solid foods were analyzed using high-performance liquid chromatography (HPLC) combined with electrospray-ionization (ESI) tandem mass spectrometry (MS/MS). (15)N-labeled PQQ was added to the samples as an internal standard. Quantitative analyses of PQQ were performed by multiple reaction monitoring (MRM) with LC/MS/MS. Free PQQ was detected in almost all food samples in the range 0.19-7.02 ng per g fresh weight (for solid foods) or per mL (liquid foods). This method will enable the rapid and simple determination of PQQ levels in many samples. 相似文献
43.
44.
Youhei MANTANI Eri ITO Miho NISHIDA Hideto YUASA Natsumi MASUDA Wang-Mei QI Junichi KAWANO Toshifumi YOKOYAMA Nobuhiko HOSHI Hiroshi KITAGAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1121-1128
Indigenous bacteria in the alimentary tract are exposed to various bactericidal
peptides and digestive enzymes, but the viability status and morphological changes of
indigenous bacteria are unclear. Therefore, the present study aimed to ultrastructurally
clarify the degeneration and viability status of indigenous bacteria in the rat intestine.
The majority of indigenous bacteria in the ileal mucous layer possessed intact cytoplasm,
but the cytoplasm of a few bacteria contained vacuoles. The vacuoles were more frequently
found in bacteria of ileal chyme than in those of ileal mucous layer and were found in a
large majority of bacteria in both the mucous layer and chyme throughout the large
intestine. In the dividing bacteria of the mucous layer and chyme throughout the
intestine, the ratio of area occupied by vacuoles was almost always less than 10%. Lysis
or detachment of the cell wall in the indigenous bacteria was more frequently found in the
large intestine than in the ileum, whereas bacterial remnants, such as cell walls, were
distributed almost evenly throughout the intestine. In an experimental control of
long-time-cultured Staphylococcus epidermidis on agar, similar vacuoles
were also found, but cell-wall degeneration was never observed. From these findings,
indigenous bacteria in the mucous layer were ultrastructurally confirmed to be the source
of indigenous bacteria in the chyme. Furthermore, the results suggested that indigenous
bacteria were more severely degenerated toward the large intestine and were probably
degraded in the intestine. 相似文献
45.
Naomi TERAMOTO Masanari IKEDA Hidetoshi SUGIHARA Takanori SHIGA Takashi MATSUWAKI Masugi NISHIHARA Kazuyuki UCHIDA Keitaro YAMANOUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(9):1416
Rhabdomyosarcoma (RMS) is an aggressive type of soft tissue sarcoma, and pleomorphic RMS is a rare subtype of RMS found in adult. p16 is a tumor suppressor which inhibits cell cycle. In human RMS, p16 gene is frequently deleted, but p16-null mice do not develop RMS. We reported that genetic ablation of p16 by the crossbreeding of p16 knock-out rats (p16-KO rats) improved the dystrophic phenotype of a rat model of Duchenne muscular dystrophy (Dmd-KO rats). However, p16/Dmd double knock-out rats (dKO rats) unexpectedly developed sarcoma. In the present study, we raised p16-KO, Dmd-KO, and dKO rats until 11 months of age. Twelve out of 22 dKO rats developed pleomorphic RMS after 9 months of age, while none of p16-KO rats and Dmd-KO rats developed tumor. The neoplasms were connected to skeletal muscle tissue with indistinct borders and characterized by diffuse proliferation of pleomorphic cells which had eosinophilic cytoplasm and atypical nuclei with anisokaryosis. For almost all cases, the tumor cells immunohistochemically expressed myogenic markers including desmin, MyoD, and myogenin. The single cell cloning from tumor primary cells gained 20 individual Pax7-negative MyoD-positive RMS cell clones. Our results demonstrated that double knock-out of p16 and dystrophin in rats leads to the development of pleomorphic RMS, providing an animal model that may be useful to study the developmental mechanism of pleomorphic RMS. 相似文献
46.
Taku Tsuyama Natsumi Shimada Taichi Motoda Yasuyuki Matsushita Yoshio Kijidani Kazuhiko Fukushima Ichiro Kamei 《Journal of Wood Science》2017,63(6):551-559
Bamboos are among the largest woody grasses and grow very rapidly. Although lignin is a crucial factor for the utilization of bamboo biomass, the lignification mechanism of bamboo shoots is poorly understood. We studied lignification in the bamboo Sinobambusa tootsik during culm development. Elongation growth began in May and ended in late-June, when the lignin content was approximately half that in mature culms. Thioacidolysis analysis indicated that p-hydroxyphenyl units in lignin formed even at late stages of lignification. The syringyl/guaiacyl ratio varied during culm development. Various lignin precursors were detected in developing culms by liquid chromatography–mass spectrometry. The ferulic acid content decreased from May to June, indicating that ferulic acid was utilized in early stages of cell wall formation. Monolignol glucosides were detected at early stages of lignification, whereas the contents of monolignols, coniferaldehyde, sinapaldehyde, p-coumaric acid, and ferulic acid peaked at later stages of lignification. Therefore, lignin precursors may be supplied differentially during the lignification process. In August, the rate of lignification decreased, although the contents of various lignin precursors peaked, implying that the rate-limiting step in the cessation of lignification in bamboo is transport or polymerization of lignin precursors, rather than their biosynthesis. 相似文献
47.
Kataoka N Nishimura M Horiuchi M Ishiguro N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(3):349-351
Surveillance of chronic wasting disease (CWD) was conducted by performing Western blot analysis of tissue samples from 136 sika deer (Cervus nippon) killed by hunters in the Tokachi district of Hokkaido Island. No prion protein (PrPSc) associated with CWD was detected in any of the samples. To assess amino acid polymorphisms of the sika deer PrP gene, nucleotide sequencing of the PrP gene was performed. The only amino acid polymorphisms detected were 3 silent mutations at nucleotide positions 63, 225 and 408. These results suggest that sika deer in the Tokachi district are genetically homogeneous, and are not infected with CWD. 相似文献