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1.
Yoshifumi Abe Atsuhiko Matsunaga Ryota Matsuzawa Toshiki Kutsuna Shuhei Yamamoto Kei Yoneki Manae Harada Ryoma Ishikawa Takaaki Watanabe Atsushi Yoshida 《PloS one》2016,11(3)
Walking ability is significantly lower in hemodialysis patients compared to healthy people. Decreased walking ability characterized by slow walking speed is associated with adverse clinical events, but determinants of decreased walking speed in hemodialysis patients are unknown. The purpose of this study was to identify factors associated with slow walking speed in ambulatory hemodialysis patients. Subjects were 122 outpatients (64 men, 58 women; mean age, 68 years) undergoing hemodialysis. Clinical characteristics including comorbidities, motor function (strength, flexibility, and balance), and maximum walking speed (MWS) were measured and compared across sex-specific tertiles of MWS. Univariate and multivariate logistic regression analyses were performed to examine whether clinical characteristics and motor function could discriminate between the lowest, middle, and highest tertiles of MWS. Significant and common factors that discriminated the lowest and highest tertiles of MWS from other categories were presence of cardiac disease (lowest: odds ratio [OR] = 3.33, 95% confidence interval [CI] = 1.26–8.83, P<0.05; highest: OR = 2.84, 95% CI = 1.18–6.84, P<0.05), leg strength (OR = 0.62, 95% CI = 0.40–0.95, P<0.05; OR = 0.57, 95% CI = 0.39–0.82, P<0.01), and standing balance (OR = 0.76, 95% CI = 0.63–0.92, P<0.01; OR = 0.81, 95% CI = 0.68–0.97, P<0.05). History of fracture (OR = 3.35, 95% CI = 1.08–10.38; P<0.05) was a significant factor only in the lowest tertile. Cardiac disease, history of fracture, decreased leg strength, and poor standing balance were independently associated with slow walking speed in ambulatory hemodialysis patients. These findings provide useful data for planning effective therapeutic regimens to prevent decreases in walking ability in ambulatory hemodialysis patients. 相似文献
2.
Kei Watanabe Kenta Wada Tomoko Ohashi Saki Okubo Kensuke Takekuma Ryoichi Hashizume Jun-Ichi Hayashi Tadao Serikawa Takashi Kuramoto Yoshiaki Kikkawa 《PloS one》2012,7(11)
We discovered a new cataract mutation, kfrs4, in the Kyoto Fancy Rat Stock (KFRS) background. Within 1 month of birth, all kfrs4/kfrs4 homozygotes developed cataracts, with severe opacity in the nuclei of the lens. In contrast, no opacity was observed in the kfrs4/+ heterozygotes. We continued to observe these rats until they reached 1 year of age and found that cataractogenesis did not occur in kfrs4/+ rats. To define the histological defects in the lenses of kfrs4 rats, sections of the eyes of these rats were prepared. Although the lenses of kfrs4/kfrs4 homozygotes showed severely disorganised fibres and vacuolation, the lenses of kfrs4/+ heterozygotes appeared normal and similar to those of wild-type rats. We used positional cloning to identify the kfrs4 mutation. The mutation was mapped to an approximately 9.7-Mb region on chromosome 7, which contains the Mip gene. This gene is responsible for a dominant form of cataract in humans and mice. Sequence analysis of the mutant-derived Mip gene identified a 5-bp insertion. This insertion is predicted to inactivate the MIP protein, as it produces a frameshift that results in the synthesis of 6 novel amino acid residues and a truncated protein that lacks 136 amino acids in the C-terminal region, and no MIP immunoreactivity was observed in the lens fibre cells of kfrs4/kfrs4 homozygous rats using an antibody that recognises the C- and N-terminus of MIP. In addition, the kfrs4/+ heterozygotes showed reduced expression of Mip mRNA and MIP protein and the kfrs4/kfrs4 homozygotes showed no expression in the lens. These results indicate that the kfrs4 mutation conveys a loss-of-function, which leads to functional inactivation though the degradation of Mip mRNA by an mRNA decay mechanism. Therefore, the kfrs4 rat represents the first characterised rat model with a recessive mutation in the Mip gene. 相似文献
3.
Jean L. Santos Paulo R. Yamasaki Chung Man Chin Célio H. Takashi Fernando R. Pavan Clarice Q.F. Leite 《Bioorganic & medicinal chemistry》2009,17(11):3795-3799
New phthalimide derivatives were easily prepared through condensation of phthalic anhydride and selected amines with variable yields (70–90%). All compounds (3a–l) were evaluated against Mycobacterium tuberculosis H37Rv using Alamar Blue susceptibility. The compounds 3c, 3i, and 3l have the minimum inhibitory concentrations (MICs) of 3.9, 7.8, and 5.0 μg/mL, respectively, and could be considered new lead compounds in the treatment of tuberculosis and multi-drug resistant tuberculosis. 相似文献
4.
Biosynthesis of locust apolipophorin-III (apo-III) was studied in vitro. Gel electrophoresis and immunoblotting analyses of the locust hemolymph demonstrated that apo-III first appears in the hemolymph on the day 3 of the adult stage after the final molt and its hemolymph concentration increases thereafter. When incubated in vitro in a medium containing radioactive amino acid, the fat body cells synthesized the radiolabeled apo-III and released it into the medium. The developmental change in the apo-III synthesizing activity in the fat body reflected that of the apo-III concentration in the hemolymph. RNA isolated from the adult fat body directed the synthesis of apo-III as a major translation product in a cell-free system. These results indicate that the fat body is the tissue responsible for the synthesis of the locust apo-III, and biosynthesis of apo-III is developmentally regulated at the level of mRNA in accordance with the flight activity of the locust. 相似文献
5.
Kyriacos Athanasiou Iordanis Arzimanoglou Colette Piccoli Hiroshi Yamasaki 《Cell biology and toxicology》1987,3(3):251-261
Airborne particulates were collected over a period of twelve months by the use of Hi-Vol samplers in the basin of Athens, Greece. N-Hexane extracts were tested in a battery ofin vitro tests for their ability to induce mutation in bacteria as well as mutation, sister chromatid exchange and morphological transformation in cultured mammalian cells. Positive results were found for mutagenicity withSalmonella strain TA98 in the Ames assay, for sister chromatid exchange induction in CHO cells and for transformation in BALB/c 3T3 cells in culture. They also showed weak non-doserelated induction of ouabain resistance in BALB/c 3T3 cells. The contribution of oxidizing and nitrating agents found in the Athens atmosphere, together with sunlight UV irradiation in the formation of direct acting mutagens and potential carcinogens from ambient polycyclic aromatic hydrocarbons, is suggested.Abbreviations FCS
fetal calf serum
- FPG
fluorescent-plus-Giemsa technique
- ouaR
ouabain resistant
- PAH
polycyclic aromatic hydrocarbon
- SCE
sister chromatid exchange
- TSP
total suspended particulate 相似文献
6.
Interleukin-6 triggers the association of its receptor with a possible signal transducer, gp130 总被引:109,自引:0,他引:109
T Taga M Hibi Y Hirata K Yamasaki K Yasukawa T Matsuda T Hirano T Kishimoto 《Cell》1989,58(3):573-581
Interleukin-6 mediates pleiotropic functions in various types of cells through its specific receptor (IL-6-R), the cDNA of which has already been cloned. We report here that an 80 kd single polypeptide chain (IL-6-R) is involved in IL-6 binding and that IL-6 triggers the association of this receptor with a non-ligand-binding membrane glycoprotein, gp130. The association takes place at 37 degrees C within 5 min and is stable for at least 40 min in the presence of IL-6, but does not occur at 0 degree C. Human IL-6-R can associate with a murine gp130 homolog and is functional in murine cells. Mutant IL-6-R lacking the intracytoplasmic portion is functional, suggesting that the two polypeptide chains interact to involve their extracellular portion. In fact, a soluble IL-6-R lacking the transmembrane and intracytoplasmic domains can associate with gp130 in the presence of IL-6 and mediate its function. These findings indicate that the complex of IL-6 and IL-6-R can interact with a non-ligand-binding membrane glycoprotein, gp130, extracellularly and can provide the IL-6 signal. 相似文献
7.
Effect of lard and corn oil intake on serum lipids in young men 总被引:2,自引:0,他引:2
M Imaki T Miyoshi S Tanada T Nakamura Y Yamada R Yamasaki H Terada 《Acta biologica Hungarica》1989,40(3):271-282
An experimental diet with lard (30 g/day for 7 days) and corn oil (30 g/day for 7 days) on high carbohydrate (basal diet) was given to four healthy Japanese young men and the effect of diets containing different fat on serum lipids was examined. Serum total cholesterol was increased significantly from a basal diet of 106 +/- 23 to 141 +/- 26 mg/dl on lard diet, and then decreased significantly (p less than 0.05) to 111 +/- 22 mg/dl on corn oil diet. Serum triglycerides increased significantly (p less than 0.01) from 66 +/- 38 to 173 +/- 32 mg/dl on basal diet. Serum HDL-cholesterol was decreased significantly (p less than 0.01) from 41.9 +/- 1.6 to 31.2 +/- 3.8 mg/dl on lard diet and increased significantly (p less than 0.05) to 41.9 +/- 4.6 mg/dl on corn oil diet. Serum HDL-cholesterol fraction was decreased significantly (p less than 0.01) from 41.6 +/- 4.9 to 28.1 +/- 3.2% on basal diets, but increased significantly (p less than 0.05) to 44.3 +/- 3.1% on lard diet, and then decreased to 36.3 +/- 2.5% on corn oil diet. Serum HDL phospholipid fraction decreased significantly (p less than 0.05) from 62.5 +/- 6.7 to 50.7 +/- 1.8% on basal diet and increased significantly (p less than 0.05) to 60.4 +/- 1.0% on lard and corn oil diet. Serum phospholipids did not change by experimental diets. It is concluded that lard and corn oil have different and specific roles in lipid metabolism. 相似文献
8.
Mutagenesis of human granulocyte colony stimulating factor 总被引:9,自引:0,他引:9
T Kuga Y Komatsu M Yamasaki S Sekine H Miyaji T Nishi M Sato Y Yokoo M Asano M Okabe 《Biochemical and biophysical research communications》1989,159(1):103-111
To define the structure-function relationship, we have made a number of mutants of human granulocyte colony-stimulating factor (hG-CSF) by in vitro mutagenesis. The results indicate that most of the mutations located in the internal and C-terminal regions of the molecule abolished the activity, whereas the mutants without N-terminal 4, 5, 7, or 11 amino acids retained the activity. N-terminal amino acids were also altered by cassette mutagenesis using a synthetic oligonucleotide mixture. Among them, KW2228, in which Thr-1, Leu-3, Gly-4, Pro-5 and Cys-17 were respectively substituted with Ala, Thr, Tyr, Arg and Ser, showed more potent granulopoietic activity than that of intact hG-CSF both in vitro and in vivo. 相似文献
9.
Hajime Yamasaki Eizo Okamoto Toshinori Komatsu Yuich Manabe Sohei Shinka 《Cancer immunology, immunotherapy : CII》1990,31(2):107-114
Summary The levels of a variety of immunological parameters were examined in 203 preoperative patients with hepatocellular carcinoma (HCC) at various stages (I–IV). The changes in the peripheral blood lymphocyte (PBL) count, the serum level of immunosuppressive acidic protein and the degree of the skin reaction to purified protein derivative were associated significantly with the stage of HCC progression. However, the percentages of lymphocyte subsets, mitogenic responsiveness of PBL and serum immunoglobulin concentration remained at the levels of stage I. Further study demonstrated that in patients undergoing hepatic artery ligation, there were statistically significant correlations between the PBL count, immunosuppressive acidic protein concentration and intensity of the skin reaction to purified protein derivative, assayed 1 month after surgery, and the prognosis. HCC-specific immunity was examined in 34 patients treated by hepatic resection or hepatic artery ligation using in vitro responses of PBL to HCC extracts (ATS test). This test was performed using culture medium containing added arginine. None of the PBL from the patients showed a positive response to allogeneic HCC extracts, but the PBL from 12 patients (9 hepatic resections, 3 hepatic artery ligations) were stimulated significantly (SI 2.5) with autologous HCC extracts. In 7 of 9 hepatic resection patients who were positive in the ATS test, tumor recurrence was identified. Statistical analysis indicated that the ATS test result was significantly correlated with tumor recurrence in hepatic resection patients. Autologous-PBL-stimulating activities were isolated in a fraction at pH 8.3 and in fractions at pH 6.7–7.0 by chromatofocusing of the crude extract. Although identification of the HCC-specific antigen remains to be done, use of the above fractions may simplify the ATS test procedure and improve its sensitivity. 相似文献
10.
N Kan S Yamasaki T Harada K Satoh Y Ichinose Y Moriguchi H Kodama K Ohgaki 《Human cell》1992,5(3):236-242
Among several approaches to augment the therapeutic effect of adoptive immunotherapy, we focused the antitumor synergy between transferred killer cells and host's fresh lymphocytes. Immunotherapy models using murine tumors or clinical experiments revealed that preadministration of immunostimulator such as OK-432, followed by chemotherapeutic agents such as cyclophosphamide, can induce host's non-cytotoxic fresh lymphocytes that act synergistically with cultured killer cells against autologous tumor cells. Immuno-chemo-lymphocytotherapy (a sequential treatment with OK-432, chemotherapy and adoptive immunotherapy) is useful to treat the patients with advanced cancer even if the number of transferred lymphocytes is limited. 相似文献