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T Sanaka

Publications and source records attributed to T Sanaka.

At least 19 recordsLinked to original sources
PubMed2003

Detection and clinical significance of Ba2+- and Sr2+-dependent antiprothrombin antibodies in patients with systemic lupus erythematosus and antiphospholipid syndrome.

We conducted this study to confirm whether or not Ca2+-dependent antiprothrombin antibody (aPT) in patients' sera with systemic lupus erythematosus and/or primary antiphospholipid syndrome would react to prothrombin/phosphatidylserine in the presence of Sr2+, Mn2+ or Ba2+, or divalent metal ions like Ca2+, utilizing ELISA, and to analyze the clinical significance of these metal-dependent aPT. We found the presence of Ba2+- and Sr2+-dependent IgG, IgM and IgA-aPT in up to 65% of patients negative for Ca2+-dependent IgG-, IgM and IgA-aPT. Maximally 69% of them were complicated by antiphospholipid syndrome-related symptoms. These data suggest that the measurement of Ba2+- and Sr2+- along with Ca2+-dependent aPT may become a clinically useful tool to correctly detect patients with antiphospholipid-related complications. However, further study is needed to clarify the clinicopathological differences among these aPTs in the future.

Adult↗
PubMed2002

Two antiprothrombin antibodies against prothrombin and prothrombin-phosphatidyl serine show partial but not total identity.

Recently, an enzyme-linked immunosorbent assay (ELISA) using prothrombin (PT) as the antigen has become a widely used test. Two ELISA methods for the detection of antiprothrombin antibody have been used extensively: one method employs PT as an antigen (aPT), and the other employs PT and phosphatidyl serine (aPT/PS) as antigens along with Ca. However, the results obtained by the two methods are not necessarily consistent with each other even using the same samples, suggesting the possibility that aPT and aPT/PS are different antibodies. We conducted an investigation to determine whether aPT and aPT/PS are identical or different antibodies. Five patients who were positive for both tests become negative to aPT after absorption with an aPT-ELISA plate or fluid-phase PT; however, they retained reactivity to aPT/PS after the same absorption procedure. These results suggest that aPT and aPT/PS are partially identical, yet still different antibodies. However, further examination employing more samples may be needed to verify our hypothesis including clarification of the clinicopathological significance of these antibodies in the future.

Adult↗
PubMed2001

Outcomes of hemodiafiltration based on Japanese dialysis patient registry.

Effectiveness of various therapeutic modalities was analyzed among 1,196 patients entered in the registry of the Japanese Society for Dialysis Therapy who were on hemopurification therapy as of the end of 1998 and developed dialysis-related amyloidosis during 1999. In the investigation, the effectiveness of various hemopurification modalities on the dialysis-related amyloidosis was ranked as exacerbation, unchanged, or alleviation, so as to analyze the possible relationship between the hemopurification modality and its effectiveness. The analysis was performed using a logistic regression approach, and the results were shown as "the risk of a worse therapeutic ranking" among the hemopurification modalities. The smaller "the risk of a worse therapeutic effect" was, the more effective the treatment modality. When the risk of a worse therapeutic effect for the hemodialysis patients treated by a regular membrane was put at 1.0, the risk for hemodialysis patients using high-flux membrane was 0.489, the off-line hemodiafiltration risk was 0.117, the on-line hemodiafiltration risk was 0.013, and the risk of push/pull hemodiafiltration was 0.017. For hemodialysis with a beta(2)-microglobulin adsorption column, a low risk of 0.054 was found. The results indicated that hemodiafiltration therapy and simultaneous hemodialysis with beta(2)-microglobulin adsorption therapy were more effective treatment for dialysis-related amyloidosis.

Amyloidosis↗
PubMed2000

Reduction of neutrophil activation by vitamin E modified dialyzer membranes.

BACKGROUND/AIM: Transient leukopenia during hemodialysis due to neutrophil activation is attributed to bioincompatibility of the dialysis membrane, but the mechanism remains unclear. We studied the mechanism of neutrophilic activation by comparing a vitamin E modified membrane (CLEE) and a regular cellulose membrane (CLSS). METHODS: (1) CLSS and CLEE membranes were used in a crossover clinical study in 7 chronic hemodialysis patients. Neutropenia, CD11b expression, and plasma C3a and myeloperoxidase concentrations were compared between the two dialyzer membranes. (2) Normal blood was circulated through CLEE and CLSS minimodels, and the same parameters were compared. (3) Blood samples with modified complement activities (EDTA: both classical and alternative pathways inactivated; EGTA+Mg: classical pathway inactivated; heating: alternative pathway inactivated; control: no modification) were incubated in the CLSS minimodel, and the neutrophilic activation was compared. RESULTS: In clinical hemodialysis, neutropenia, CD11b expression, and C3a and myeloperoxidase levels were significantly lower when CLEE membranes were used. The same tendency was observed in minimodels. However, the degrees of inhibition in clinical dialysis, especially at the venous line, were significantly higher than in minimodels. As compared with controls, CD11b expression and myeloperoxidase level were significantly lower when both classical and alternative pathways were inactivated or when the classical pathway alone was inactivated, but were not significantly different when the alternative pathway alone was inactivated. CONCLUSIONS: Vitamin E modification of the dialyzer reduces some reactions of neutrophilic activation, such as CD11b expression and myeloperoxidase release, more effectively in the clinical situation than in ex vivo models, suggesting a possible effect of vitamin E in inhibiting bioreactions due to pyrogen in the dialysate. The classical complement pathway is required in membrane-induced neutrophilic activation, at least during the initial stage.

Adult↗
PubMed2000

[The effects of ACE inhibitor treatment and ACE gene polymorphism on erythropoiesis in chronic hemodialysis patients].

Aggravation of anemia in chronic renal failure patients by angiotensin-converting enzyme inhibitors (ACEIs) has been attributed to the inhibition of angiotensin II which facilitates erythropoietin(Epo) production. This study was aimed at evaluating whether ACEIs aggravate anemia in maintenance hemodialysis patients and to investigate the influence of ACE gene polymorphism on erythropoiesis in these patients. Ninety-one hemodialysis patients were divided into 2 groups, based on whether or not they were administered ACEIs, into the ACEI group(n = 24) and the non-ACEI group(n = 67), and comparisons were made of the doses of recombinant human Epo(rHuEpo) administered, the hematocrit(Hct) and the plasma Epo concentrations. Among the patients in the non-ACEI group, only 17 did not receive rHuEpo, while all of the patients in the ACEI group received rHuEpo. The average dose of rHuEpo was 102.7 +/- 45.4 IU/kg/week in the ACEI group and 57.8 +/- 55 IU/kg/week in the non-ACEI group and the difference between the two groups was statistically significant. A statistically significant difference in the Hct was also observed between the two groups: the mean Hct in the ACEI group was 28.7 +/- 2.9% while that in the non-ACEI group was 31.1 +/- 3.7%. The plasma Epo concentrations were significantly lower in the ACEI group than in the non-ACEI group. No significant differences in the rHuEpo dose and Hct were observed between the three ACE genotype classes in either the ACEI or the non-ACEI group, however, there was a significant difference among the three genotypes in the non-ACEI group in regard to the plasma Epo concentrations; patients with the DD genotype had higher concentrations than those with the DI or II genotypes. These data suggest that anemia in maintenance hemodialysis patients is worsened by ACEIs as a result of the suppression of Epo production. Although it has been suggested that the endogenous Epo concentrations in maintenance hemodialysis patients are associated with ACE gene polymorphism, no significant influence of the ACE genotype on the rHuEpo dose or Hct was evident. Therefore, it is possible that exacerbation of anemia by ACEIs in the patients receiving rHuEpo is a result of an inhibited bone marrow response to Epo.

Adult↗
PubMed1999

Eicosapentanoic acid reduces plasma levels of remnant lipoproteins and prevents in vivo peroxidation of LDL in dialysis patients.

Causative factors of uremia-associated atherosclerosis are complex. However, it is likely that atherogenic lipoproteins accumulated in plasma are involved. Remnant lipoproteins are atherogenic and are frequently observed in uremic plasma. LDL from uremic patients has been shown to be susceptible to in vitro peroxidation, suggesting that oxidized LDL (ox-LDL) could be excessively generated in those patients. No effective treatments to prevent accumulation of both atherogenic lipoproteins in dialysis patients have been published. Eicosapentanoic acid (EPA) may change synthesis and/or catabolism of remnant lipoproteins and increase stability of LDL to peroxidation by altering the fatty acid composition of lipoproteins. A prospective comparative study was conducted to assess the efficacy of EPA on metabolism of remnant lipoproteins and ox-LDL in dialysis patients using two new methods: an immunoaffinity gel separation for quantifying plasma remnant lipoproteins and an enzyme-linked immunosorbent assay for measuring plasma ox-LDL levels, a marker for in vivo LDL peroxidation. Twenty-two hemodialysis and 16 continuous ambulatory peritoneal dialysis patients with relatively high plasma levels of remnant lipoproteins and ox-LDL were randomized to either EPA or placebo. Highly purified EPA, in an ethyl-ester form (ethyl all-cis-5,8,11,14,17-icosapentanoate) with a purity greater than 91%, was administered at a dose of 1800 mg daily. Overall, 3 mo of treatment with EPA significantly reduced the levels of both remnant lipoproteins (52% reduction) and ox-LDL (38% reduction). Additionally, gel filtration chromatography of lipoproteins showed that EPA treatment concomitantly normalized other potential abnormalities in lipoproteins. Treatment compliance was good and no critical adverse effects were observed. In conclusion, EPA administration proved to be effective and safe treatment to decrease plasma remnant lipoproteins and prevent in vivo peroxidation of LDL in dialysis patients.

Administration, Oral↗
PubMed1997

Therapeutic effect of a newly developed antioxidative agent (OPC-15161) on experimental immune complex nephritis.

The effect of a newly developed free radical scavenger (OPC-15161) on the progression of nephrotoxic serum (NTS) nephritis was evaluated. NTS nephritis rats were sacrificed immediately before and 1, 2, 3, 6, and 24 h and 13 and 19 days after intravenous injection of NTS. The tissue content of phosphatidylcholine hydroperoxide, the activity of superoxide, the activity of superoxide dismutase in the renal cortex, and the serum malondialdehyde levels were measured. The phosphatidylcholine hydroperoxide content in the renal cortex of OPC-15161-treated NTS nephritis rats was lower than that in the control rats 24 h after NTS injection. The activity of superoxide dismutase in OPC-15161-treated rats was sustained in contrast to the decrease in this activity in the control rats 6 h after injection of NTS. The effects of OPC-15161, dipyridamole, and prednisolone on NTS nephritis rats were investigated. OPC-15161 (20 mg/kg p.o.) showed a potent inhibitory effect on the urinary protein excretion, whereas dipyridamole (30 and 100 mg/kg p.o.) and prednisolone (2 mg/kg p.o.) had less suppressive effects. In view of these results, we conclude that OPC-15161 notably ameliorated the urinary protein excretion by way of the suppression of lipid peroxidation in the renal tissue of NTS nephritis rats.

Animals↗
PubMed1997

IGF-I/IGFBP-1 as an index for discrimination between responder and nonresponder to recombinant human growth hormone in malnourished uremic patients on hemodialysis.

From a clinical aspect, there are still a number of unsolved problems in patients with end-stage renal disease, for instance intractable malnutrition. The present study was undertaken to establish the therapeutic effect of recombinant human growth hormone (r-hGH) on the nutritional state and clarify the usefulness of the insulin-like growth factor-I (IGF-I) insulin-like growth factor binding protein-1 (IGFBP-1) ratio as nutritional indices for prediction of the clinical response in uremic patients on hemodialysis. Thirty hemodialysis patients (13 females and 17 males, mean age 56.7 +/- 15.2 years) were studied who were suffering from malnutrition and could not be treated by any of the usual nutritional therapies; they were subjected to 0.5 IU/kg/week of r-hGH subcutaneously after hemodialysis for 2 weeks. Blood samples were collected for measurement of the following plasma biochemical and hematological indices: serum IGF-I, IGFBP-1, growth hormone, total protein (TP), prealbumin, transferrin, albumin, serum urea nitrogen (SUN), creatinine, hematocrit, and amino acids. Immediately after r-hGH administration, SUN, essential amino acid and nonessential amino acid changed from 67.7 +/- 12.3 to 56.5 +/- 10.5 mg/dl (p < 0.05), from 798 +/- 84 to 1,115 +/- 208 microM/l (p < 0.05 vs. baseline), and from 2,185 +/- 221 to 2,814 +/- 621 microM/l (p < 0.05), respectively. Serum IGF-I increased markedly from 193 +/- 49 to 321 +/- 81 ng/ml, whereas serum IGFBP-1 decreased from 139 +/- 13 to 81 +/- 19 micrograms/l (p < 0.05). Four weeks after r-hGH administration, serum TP and albumin increased from 5.5 +/- 0.2 to 6.0 +/- 0.3 g/dl (p < 0.05) and from 3.2 +/- 0.2 to 3.6 +/- 0.3 g/dl (p < 0.05), respectively. Serum IGF-I/IGFBP-1 ratio was significantly higher in patients with an increase of 0.5 g/dl or more in serum albumin than in other patients with poor response and the control group before r-hGH administration. Patients with marked improvement in serum albumin showed an IGF-I/IGFBP-1 ratio of 2 or less. On the other hand, patients without favorable improvement in serum albumin had a higher ratio of 4 or more. We conclude that r-hGH and IGF-I improve the malnutritional state by alleviating hypoproteinemia and abnormality of serum amino acid profile in uremic patients on hemodialysis. In addition, the serum IGF-I/IGFBP-1 ratio is useful not only as a nutritional parameter but also as a predicting index of responsiveness to r-hGH.

Amino Acids↗