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71.
A new ascomycete species,Plagiostoma phragmiticola inhabiting two reed plants,Phragmites australis andP. karka, is described and illustrated. This new species is characterized by having non-stromatic, solitary perithecia, laterally
and obliquely protruding perithecial beaks, and relatively small asci and ascospores. Black zone-lines in colonized leaf tissues
were not observed. Its anamorph belongs toPhomopsis. 相似文献
72.
Introduction
Recent epidemiological studies show that high intakes of carotenoids might be useful to maintain bone health, but little is known about the association of serum carotenoids with change of bone mineral density (BMD). The objective of this study was to investigate longitudinally whether serum carotenoids are associated with bone loss.Methods
We conducted a follow-up on 146 male and 99 pre- and 212 post-menopausal female subjects from the Mikkabi study. Those who participated in previous BMD surveys and completed four years of follow-up were examined longitudinally.Results
During a 4-year follow-up, 15 of the post-menopausal female subjects developed new-onset osteoporosis. In contrast, none of the male and pre-menopausal female subjects did. In male and pre-menopausal female subjects, the six serum carotenoids at the baseline were not associated with bone loss. On the other hand, in post-menopausal female subjects, the 4-year bone loss of radius was inversely associated with the serum carotenoid concentrations, especially in β-carotene. After adjustments for confounders, the odds ratios (OR) for osteoporosis in the highest tertiles of serum β-carotene and β-cryptoxanthin against the lowest tertiles were 0.24 (95% confidence interval 0.05–1.21) and 0.07 (CI: 0.01–0.88), respectively. Serum β-cryptoxanthin was also inversely associated with the risk for osteopenia and/or osteoporosis (P for trend, 0.037). In addition, our retrospective analysis revealed that subjects who developed osteoporosis and/or osteopenia during the survey period had significantly lower serum concentrations of β-cryptoxanthin and β-carotene at the baseline than those in the normal group.Conclusions
Antioxidant carotenoids, especially β-cryptoxanthin and β-carotene, are inversely associated with the change of radial BMD in post-menopausal female subjects. 相似文献73.
74.
Imaoka T Okamoto M Nishimura M Nishimura Y Ootawara M Kakinuma S Tokairin Y Shimada Y 《Radiation research》2006,165(2):165-173
The Apc(Min/+) (Min) mouse is genetically predisposed to both intestinal and mammary tumorigenesis. We investigated age-related changes in the susceptibility of mice (before, during and after puberty) to radiation-induced mammary tumorigenesis using this model. Female Min and wild-type mice having the C57BL/6J background were irradiated with 2 Gy of X rays at 2, 5, 7 and 10 weeks and killed humanely at 18 weeks of age. Min mice irradiated at 7-10 weeks of age (after puberty) developed mammary tumors with squamous metaplasia, whereas their wild-type littermates did not. Interestingly, irradiation of Min mice at 2-5 weeks (before and during puberty, respectively) did not induce mammary tumors but rather cystic nodules with metaplasia. The mammary tumors exhibited increased nuclear beta-catenin protein and loss of the wild-type Apc allele. Our results show that susceptibility to radiation-induced mammary tumorigenesis increases after puberty in Min mice, suggesting that the tumorigenic effect of ionizing radiation targets the lobular-alveolar progenitor cells, which increase in number with age and are controlled by beta-catenin signaling. 相似文献
75.
Hirotaka Tsubouchi Mieko Inuo Toshiyo Sonta Shuji Sasaki Hideki Sumimoto 《Biochemical and biophysical research communications》2004,326(1):60-65
Increased oxidative stress may play a key role in the progressive deterioration of pancreatic β-cells and the development of diabetes. However, the underlying mechanism is not well understood. Exposure of pancreatic β-cell line, MIN6 cells, to elevated glucose level for 2 h induced an increase in reactive oxygen species (ROS) production, as evaluated by the staining of 2′,7′-dichlorofluorescein diacetate. This effect was completely blocked by NAD(P)H oxidase inhibitor (diphenylene iodonium) and protein kinase C (PKC) inhibitor (calphostin C), but not affected by other flavoprotein inhibitors (rotenone, oxypurinol, or l-N-monomethyl arginine). Glibenclamide also stimulated ROS production in a dose-dependent manner. This effect was again blocked by diphenylene iodonium and calphostin C. In conclusion, insulin secretagogues, both glibenclamide and elevated glucose level, stimulated ROS production in β-cells through a PKC-dependent activation of NAD(P)H oxidase. This mechanism may be a novel therapeutic target for preventing the progression of β-cell deterioration. 相似文献
76.
Michiyo Tsuru Michio Sata Maki Tanaka Hideaki Umeyama Yoshio Kodera Mieko Shiwa Norikazu Aoyagi Kaori Yasuda Kei Matsuoka Takaaki Fukuda Hideaki Yamana Kensei Nagata 《Translational oncology》2017,10(6):998-1007
Patients who undergo surgical extirpation of a primary liver carcinoma followed by radiotherapy and chemotherapy leading to complete remission are nevertheless known to develop cancerous metastases 3–10 years later. We retrospectively examined the blood sera collected over 8 years from 30 patients who developed bone metastases after the complete remission of liver cancer to identify serum proteins showing differential expression compared to patients without remission. We detected a novel RGD (Arg-Gly-Asp)-containing peptide derived from the C-terminal portion of fibrinogen in the sera of metastatic patients that appeared to control the EMT (epithelial-mesenchymal transition) of cancer cells, in a process associated with miR-199a-3p. The RGD peptide enhanced new blood vessel growth and increased vascular endothelial growth factor levels when introduced into fertilized chicken eggs. The purpose of this study was to enable early detection of metastatic cancer cells using the novel RGD peptide as a biomarker, and thereby develop new drugs for the treatment of metastatic cancer. 相似文献
77.
Kozo Tsuchida Mieko Arai Yoshiro Tanaka Ren Ishihara Robert O Ryan Hideaki Maekawa 《Insect biochemistry and molecular biology》1998,28(12):927-934
The yellow color of Bombyx mori hemolymph is due to the presence of carotenoids, which are primarily associated with lipophorin particles. Carotenoids were extracted from high density lipophorin (HDLp) of B. mori and analyzed by HPLC. HDLp contained 33 μg of carotenoids per mg protein. Over 90% of carotenoids were lutein while -carotene and β-carotene were minor components. When larval hemolymph was subjected to density gradient ultracentrifugation, a second minor yellow band was present, which was identified as B. mori lipid transfer particle (LTP). During other life stages examined however, this second band was not visible. To determine if coloration of LTP may fluctuate during development, we determined its concentration in hemolymph and compared it to that of lipophorin. Both proteins were present during all life stages and their concentrations gradually increased. The ratio of lipophorin: LTP was 1015:1 during the fourth and fifth instar larval stages, and 2030:1 during the pupal and adult stages. Thus, there was no correlation between the yellow color attributed to LTP and its hemolymph concentration. It is possible that yellow coloration of the LTP fraction corresponds to developmental stages when the particle is active in carotene transport. To determine if LTP is capable of facilitating carotene transfer, we took advantage of a white hemolymph B. mori strain which, when fed artificial diet containing a low carotene content, gives rise to a lipophorin that is nearly colorless. A spectrophotometric, carotene specific, transfer assay was developed which employed wild type, carotene-rich HDLp as donor particle and colorless low density lipophorin, derived from the white hemolymph strain animals, as acceptor particle. In incubations lacking LTP carotenes remained associated with HDLp while inclusion of LTP induced a redistribution of carotenes between the donor and acceptor in a time and concentration dependent manner. Time course studies suggested the rate of LTP-mediated carotene transfer was relatively slow, requiring up to 4 h to reach equilibrium. By contrast, studies employing 3H-diacylglycerol labeled HDLp as donor particle in lipid transfer assays revealed a rapid equilibration of label between the particles. Thus, it is plausible that the slower rate of LTP-mediated carotene transfer is due to its probable sequestration in the core of HDLp. 相似文献
78.
Supranutrition dietary levels of the element selenium (Se) that have been shown to reduce or retard tumor development resulting
from transplantation. The rat placental form of glutathione-S-transferase (GST-p) has been reported to be a good marker for
preneoplastic or neoplastic lesions. Four groups of rats with glioma were exposed to Se-free, 0.05, 2.0, and 4.0 ppm sodium
selenite GST-p was investigated. Normal brain tissue did not differ significantly in all groups. In contrast, GST-p in tumor
was significantly higher in Se-free and 4.0-ppm groups compared to 0.5- and 2.0-ppm groups. The concentration of Se in normal
brain tissue did not differ significantly in Se-supplement groups. By contrast, Se in tumors was significantly higher in the
0.5- and 2.0-ppm groups compared to the Se-free and 4.0-ppm groups. Mean group survival at 30 d after treatment was determined
and compared with previous dietary Se. Survival was significantly longer in the 0.5- and 2.0-ppm groups than in the Se-free
and 4.0-ppm groups. The 2.0-ppm group had enhanced survival, similar to the 0.5-ppm group. The Se-free and 4.0-ppm groups
might have no protection against carcinogenesis. 相似文献
79.
80.
Katsuhiko Yokoi Mieko Kimura Yoshinori Itokawa 《Biological trace element research》1991,29(3):257-265
To clarify the influence of iron deficiency on mineral status, the following two synthetic diets were fed to male Wistar rats: a control diet containing 128 micrograms iron/g, and an iron-deficient diet containing 5.9 micrograms iron/g. The rats fed the iron-deficient diet showed pale red conjunctiva and less reactiveness than the rats fed the control diet. The hemoglobin concentration and hematocrit of the rats fed the iron-deficient diet were markedly less than the rats fed the control diet. The changes of mineral concentrations observed in tissues of the rats fed the iron-deficient diet, as compared with the rats fed the control diet, are summarized as follows: . Iron concentrations in blood, brain, lung, heart, liver, spleen, kidney, testis, femoral muscle, and tibia decreased; . Calcium concentrations in blood and liver increased; calcium concentration in lung decreased; . Magnesium concentration in blood increased; . Copper concentrations in blood, liver, spleen and tibia increased; copper concentration in femoral muscle decreased; . Zinc concentration in blood decreased; . Manganese concentrations in brain, heart, kidney, testis, femoral muscle and tibia increased. These results suggest that iron deficiency affects mineral status (iron, calcium, magnesium, copper, zinc, and manganese) in rats. 相似文献