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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.
In the undecaprenyl diphosphate synthase reaction, an allylic substrate homologue, (2Z,6E,10E)-4-methyl-geranylgeranyl diphosphate was found to be a potent competitive inhibitor against the allylic primer, (2Z,6E,10E)-geranylgeranyl diphosphate. On the other hand, it acted as a strong noncompetitive inhibitor against isopentenyl diphosphate. On the basis of these facts, the topology of the substrate-binding sites as well as the reason why the synthase reaction with (E)-3-methyl-3-pentenyl diphosphate always stops completely at the first stage of condensation, yielding an allylic diphosphate with a methyl group at the 4-position, are discussed. 相似文献
4.
Phosphorylation in the carboxyl-terminal domain of the capsid protein of hepatitis B virus: evaluation with a monoclonal antibody. 总被引:1,自引:0,他引:1
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A Machida H Ohnuma F Tsuda A Yoshikawa Y Hoshi T Tanaka S Kishimoto Y Akahane Y Miyakawa M Mayumi 《Journal of virology》1991,65(11):6024-6030
The capsid protein of hepatitis B virus (p21c) is made of 183 amino acids coded for by the C gene. By using p21c isolated from Dane particles (hepatitis B virus) as an immunogen, a monoclonal antibody (no. 2212) which recognized an epitope dependent on the phosphorylation of p21c was raised. The binding of no. 2212 antibody to authentic p21c was completely inhibited by a synthetic undecapeptide with a sequence of RRRSQSPRRRR, representing amino acids 165 to 175 of p21c, only when the peptide was phosphorylated. Either or both of Ser-168 and Ser-170 were phosphorylated in p21c in vivo, therefore, and contributed to the manifestation of the epitope. No. 2212 antibody bound to p21c from core particles derived from Dane particles or hepatocellular carcinoma tissues (PLC/342) propagated in nude mice but did not bind to p21c from core particles expressed in Escherichia coli or yeast cells, indicating different states of phosphorylation in them. Nonphosphorylated p21c showed a higher affinity for the viral DNA than did phosphorylated p21c. Since the serum from an asymptomatic carrier, with a high titer for antibody to hepatitis B core antigen, specifically bound to phosphorylated undecapeptide (amino acids 165 to 175), the epitope would stimulate humoral antibody responses in the human host. 相似文献
5.
K Takahashi S Kishimoto H Ohnuma A Machida E Takai F Tsuda H Miyamoto T Tanaka K Matsushita K Oda 《Journal of immunology (Baltimore, Md. : 1950)》1986,136(9):3467-3472
There are four polypeptides coded for by the region Pre-S and gene S on DNA of hepatitis B virus that carry the receptor for polymerized human serum albumin (poly-HSA), i.e., P31 and P39, as well as their glycosylated counterparts P35 and P43. With the use of monoclonal antibodies directed to Pre-S(1) sequence and Pre-S(2) sequence (bearing the receptor for poly-HSA), the content of these polypeptides, as well as their expression on the surface, was determined for hepatitis B particles of various categories. P39 and P43, carrying both Pre-S(1) and Pre-S(2) sequences, were contained abundantly in Dane and tubular particles, and to a much lesser extent in small spherical particles, all of which were purified from plasma containing hepatitis B e antigen (HBeAg). P31 and P35, carrying Pre-S(2) but not Pre-S(1) sequence, were contained comparably in these three categories of hepatitis B particles. In remarkable contrast, small spherical particles derived from plasma containing antibody to HBeAg were very low in the content of any Pre-S polypeptides. P31 and P39 showed higher activities for poly-HSA receptor than their glycosylated versions. When Dane particles were digested with trypsin, the poly-HSA receptor was deprived in parallel with the loss of antigenicity for Pre-S(2) sequence. The antigenicity for Pre-S(1) sequence was much less affected, and that for the product of gene S was virtually unchanged by the digestion. 相似文献
6.
Biological activity assessment of the vitamin D metabolites 1,25-dihydroxy-24-oxo-vitamin D3 and 1,23,25-trihydroxy-24-oxo-vitamin D3 总被引:3,自引:0,他引:3
Two new metabolites of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], namely 1,25(OH)2-24-oxo-vitamin D3 and 1,23,25(OH)3-24-oxo-vitamin D3, have been prepared in vitro using chick intestinal mucosal homogenates. To investigate the binding of 1,25(OH)2-[23-3H]-24-oxo-D3 and 1,23,25(OH)3-[23-3H]-24-oxo-D3 to the chick intestinal receptor we have isolated both metabolites in radioactive form using an incubation system containing 1,25(OH)2-[23,24-3H))-D3 with a specific radioactivity of 5.6 Ci/mmol. Both metabolites were highly purified by using Sephadex LH-20 chromatography followed by high-pressure liquid chromatography (HPLC). Sucrose density gradient sedimentation analysis showed specific binding of both tritium-labeled metabolites to the chick intestinal cytosol receptor. Experiments were carried out to determine the relative effectiveness of binding to the chick intestinal mucosa receptor for 1,25(OH)2D3. The results are expressed as relative competitive index (RCI), where the RCI is defined as 100 for 1,25(OH)2D3. Whereas the RCI obtained for 1,25(OH)2-24-oxo-D3 was 98 +/- 2 (SE), the RCI for 1,23,25(OH)3-24-oxo-D3 was only 28 +/- 6 (SE). Also, the biological activity of both new metabolites was assessed in vivo in the chick. In our assay for intestinal calcium absorption, 1,25(OH)2-24-oxo-D3 was active at a dose level of 1.63 and 4.88 nmol/bird (at 14 h), whereas 1,23,25(OH)3-24-oxo-D3 showed only weak biological activity in this system. In our assay for bone calcium mobilization, administration of both new metabolites showed modest activity at the 4.88-nmol dose level, which was reduced at the 1.63-nmol dose level. The results indicate that biological activity declines as 1,25(OH)2D3 is metabolized to 1,24R,25(OH)3D3, 1,25(OH)2-24-oxo-D3, and then 1,23,25(OH)3-24-oxo-D3. 相似文献
7.
8.
Shinji Takai Nariaki Fukunaga Kei Kamisawa Yumiko Imai Yukako Sasaki Shiro Tsubaki 《Microbiology and immunology》1996,40(8):591-594
We recently reported that there are two different virulence-associated antigens correlated with virulence levels in Rhodococcus equi isolates from AIDS patients: virulent R. equi that kills mice with 106 cells expresses 15- to 17-kDa antigens and intermediately virulent R. equi that kills mice with 107 cells expresses a 20-kDa antigen. Environmental parameters were evaluated for their effects on the expression of these virulence-associated antigens in virulent R. equi strains by immunoblotting using monoclonal antibodies in this study. Expression of these two virulence-associated antigens of R. equi was regulated by pH and temperature; the antigens were produced maximally when the isolates were grown at 38 C and pH 6.5, but were not produced when grown at 38 C and pH 8, nor at temperatures below 30 C. The 20-kDa antigen was found to be located on the cell surface, as were the 15- to 17-kDa antigens, and showed susceptibility to proteolysis by trypsin. These results indicate that expression of the virulence-associated antigens of R. equi is dependent on the environmental conditions. 相似文献
9.
10.
Zenjiro Osawa Tsubura Morota Kenichi Hatanaka Toshihiro Akaike Kei Matsuzaki Hideki Nakashima Naoki Yamamoto Eiichiro Suzuki Hiroshi Miyano Tohru Mimura Yutaro Kaneko 《Carbohydrate polymers》1993,21(4):283-288
Sulfopropyl curdlan was synthesized, its structure was determined, and the anti-HIV activity was compared with that of standard curdlan sulfates obtained with piperidine N-sulfonic acid in dimethyl sulfoxide. It was shown that sulfopropyl curdlan exhibits weaker anti-HIV activity than curdlan sulfate. Curdlan sulfates were synthesized with a SO3-pyridine complex in a heterogeneous phase. It was shown from 13C-NMR spectra of acetylated curdlan sulfates that they had a different substituent distribution from standard curdlan sulfate. The cytotoxicity of the curdlan sulfates was attributed to their heterogeneous structure. 相似文献