Search PubMed⌕ Search

Biomedical subjects

Tadao Akizawa

Publications and source records attributed to Tadao Akizawa.

66 records · Page 4Linked to original sources
PubMed2003

Clinical effect of short daily in-center hemodialysis.

BACKGROUND: The safety and efficacy of short daily hemodialysis has been reported in the USA and Europe, but there is no report on its efficacy in Japanese patients undergoing hemodialysis. METHODS: Twenty-three outpatients (14 men and 9 women, 55.8 +/- 9.6 years old and 11.1 +/- 6.6 years on dialysis) undergoing hemodialysis 3 times/week participated in this study. After 4 weeks' baseline observation under conventional hemodialysis, they were subjected to short daily in-center hemodialysis (DHD, 6 times/week) for 12 weeks and then a 4-week follow-up observation period under conventional hemodialysis. RESULTS: The mean pre-dialysis systolic and diastolic blood pressure significantly decreased in the DHD period. Antihypertensive drugs could be discontinued or the dose was reduced in 6 of 11 patients treated with such drugs. The hematocrit level tended to increase in the DHD period, and recombinant human erythropoietin could be discontinued or reduced in 7 of 14 patients. Localized skin rash caused by the adhesive tape and lidocaine patch at the blood access was observed in only 2 patients, but no other adverse events associated with DHD were noted. CONCLUSION: These results indicate that DHD is safe and more useful than conventional 3 times/week hemodialysis for Japanese patients undergoing hemodialysis.

Ambulatory Care Facilities↗
PubMed2003

[Renal osteodystrophy and vitamin D].

Vitamin D deficiency is one of major pathogeneses of renal osteodystrophy (ROD). Vitamin D deficiency produces osteitis fibrosa via secondary hyperparathyroidism and osteomalacia via hypocalcemia. To prevent and treat ROD, vitamin D supplementation is an inevitable tool. Recent progresses of vitamin D therapy including development of new vitamin D analogues and direct injection to parathyroid gland will contribute to the successful treatment of ROD.

English Abstract↗
PubMed2002

Improvements in artery occlusion by low-density lipoprotein apheresis in a patient with peripheral arterial disease.

Peripheral arterial disease (PAD; arteriosclerosis obliterans) shows ischemic symptoms along the peripheral arteries due to reduced blood flow, and the number of patients with PAD is increasing. Several papers have reported on the clinical effect of low-density lipoprotein apheresis (LDL-A) on PAD, but there has been no report so far on the improvement of total peripheral artery stenosis by LDL-A. We report on the clinical course of a female PAD patient with intractable decubitus in her heel due to the complete occlusion of anterior tibial artery who was treated by a series of LDL-A sessions. The complete occlusion of the anterior tibial artery improved as seen on angiography, and the decubitus in her heel also markedly improved after LDL-A therapy. This report supports the clinical benefit of LDL-A for the treatment of PAD.

Aged↗
PubMed2002

Effects of 1,25-dihydroxy-22-oxavitamin D(3) on parathyroid gland function in haemodialysis patients with secondary hyperparathyroidism.

Secondary hyperparathyroidism (2HPT) is characterized by an abnormal threshold for suppression of parathyroid hormone (PTH) secretion by serum ionized Ca (ICa). It is therefore critical to examine the threshold of PTH secretion in chronic renal failure patients in relation to the physiopathological conditions and the severity of 2HPT. The effect of 1,25-dihidroxy-22-oxavitamin D(3) (22-oxacalcitriol, OCT) on parathyroid gland function was investigated in six haemodialysis patients with 2HPT. OCT was administered three times a week for 26 consecutive weeks. The maximum serum PTH (PTHmax), the minimum serum PTH (PTHmin), and ICa concentration required to inhibit 50% of PTHmax were estimated based on the model formula of the sigmoid curve describing the relationship between ICa and intact-PTH levels. The sigmoid ICa-PTH curves displayed a downward shift at 12 and 26 weeks of OCT treatment. Parathyroid gland function, as reflected by both PTHmax and PTHmin, decreased over time. A steep slope was found at 12 and 26 weeks, compared with that at the start of OCT treatment. There were no marked changes in the set point of calcium. Hypercalcaemia and elevated creatine phosphokinase, probably due to OCT therapy, were observed during the study period. In view of the findings that the sigmoid ICa-PTH curve displayed a downward shift, that both PTHmax and PTHmin decreased, and that functional mass of the parathyroid gland was reduced, OCT appears to be useful in ameliorating parathyroid gland function, contributing to the management of 2HPT.

Adult↗
PubMed2002

Long-term effect of 1,25-dihydroxy-22-oxavitamin D(3) on secondary hyperparathyroidism in haemodialysis patients. One-year administration study.

A trial on the long-term administration of 1,25-dihydroxy-22-oxavitamin D(3) (22-oxacalcitoriol, OCT) was conducted among 124 patients with chronic renal failure on maintenance haemodialysis (HD) complicated with secondary hyperparathyroidism (2HPT). In the trial, OCT was administered three times weekly for 26 weeks subsequent to a 26-week pre-trial. As a result, intact-parathyroid hormone (PTH) levels fell significantly after the start of administration and, at the end of the trial, PTH was decreased by over 30% in 51.6% (64/124) of the patients, and the levels of bone metabolism markers such as alkaline phosphatase (ALP), bone ALP, and tartrate-resistant acid phosphatase (TRACP) were significantly decreased compared with those at the start of administration, suggesting a correction of high-turnover bone disease. Serum calcium (Ca) levels rose significantly following OCT administration, but were successfully maintained within a physiological level. Hypercalcaemia, which was diagnosed in 33.1% of patients, was found to resolve or ameliorate immediately after the withdrawal or dose reduction of OCT. OCT can be administered for as long as 1 year without any major problems other than hypercalcaemia. The final doses ranged from 2.5 to 20.0 microg/HD, and the optimal dose varied among patients depending on the intact-PTH and adjusted serum Ca levels. These results suggest that OCT is a highly effective drug for the suppression of PTH levels in 2HPT, and is an overall safe drug if the dosage is adjusted for serum Ca and intact-PTH levels. This study confirmed that the long-term (1-year) administration of OCT is very useful for the treatment of 2HPT.

Adult↗
PubMed2002

Clinical effects of L-threo-3,4-dihydroxyphenylserine on orthostatic hypotension in hemodialysis patients.

Orthostatic hypotension is one of the major factors interfering with everyday activities in hemodialysis patients, but there has been no effective agent for treating it. In order to clarify the clinical effects of L-threo-3,4-dihydroxyphenylserine (L-DOPS) on orthostatic hypotension of hemodialysis patients, we conducted a randomized, double-blind comparative trial. 149 regular hemodialysis patients with orthostatic hypotension were randomly allocated to three groups and L-DOPS at doses of 400 mg, 200 mg or placebo was orally administrated to each group 30 min before starting every hemodialysis for 4 weeks. Changes of blood pressure (BP) in orthostatic hypotension immediately after completion of hemodialysis and symptoms related to orthostatic hypotension were compared between the three groups. In the 400-mg group, systolic and diastolic BP after standing increased significantly and the drop of mean BP after standing was also reduced compared with pretreatment levels. No such changes were observed in the placebo group. Fatiguability, malaise/weakness, dizziness and light-headed feeling, the interdialytic symptoms commonly observed in hemodialysis patients who developed orthostatic hypotension, were improved to a significant extent in the L-DOPS group compared with the placebo group. In particular, the improvement was more remarkable for the L-DOPS 400-mg group than the placebo group in patients with diabetic nephropathy, lower systolic BP after standing, and the long duration type of orthostatic hypotension. The incidence of adverse events was comparable between the three groups, and all recovered after discontinuation of L-DOPS or concomitantly administered drugs, or without any treatment. These findings indicate that L-DOPS taken before hemodialysis prevents orthostatic hypotension in patients undergoing hemodialysis, and is also effective for the interdialytic symptoms related to orthostatic hypotension.

Aged↗
PubMed2002

Diagnostic significance of serum soluble transferrin receptors in various anemic diseases: the first multi-institutional joint study in Japan.

Serum soluble transferrin receptor (sTfR) has been reported to be higher in patients with iron deficiency or with elevated erythropoiesis. In the present study, serum sTfR was measured in various anemic diseases and their clinical significance was examined in a multi-institutional joint study. Serum sTfRs in patients with the following anemic diseases were markedly higher than those in normal healthy adults: non-treated iron deficiency anemia (IDA) (9.13 +/- 7.04 mg/l, n = 52, p < 0.0001), anemia of chronic disorders (ACD) (3.45 +/- 1.38 mg/l, n = 20, p < 0.0001), hemolytic anemia (HA) (5.57 +/- 3.26 mg/l, n = 17, p < 0.0001), and myelodysplastic syndrome (MDS) (4.03 +/- 2.83 mg/l, n = 20, p < 0.0001). There were significant differences between IDA and ACD (p < 0.0001), between aplastic anemia (AA) (1.58 +/- 1.26 mg/l, n = 16) and MDS (p < 0.001), and between AA and MDS with refractory anemia (MDS-RA) (4.16 +/- 3.40 mg/l, n = 9) (p < 0.02). In patients with chronic renal failure (CRF), serum sTfR levels and serum sTfR/log serum ferritin ratios (sTfR/F index) were compared in the two classified groups according to Muirhead's criteria, as IDA and non-IDA groups with or without recombinant human erythropoietin (rHuEPO) treatment. Significantly high levels of both serum sTfR (p < 0.0001) and the sTfR/F index (p < 0.0001) were observed in IDA without rHuEPO treatment. Especially in CRF with rHuEPO treatment, the sTfR/F index showed marked elevation in the IDA group (p < 0.0001) compared with serum sTfR (p < 0.001), indicating more diagnostic efficacy of the sTfR/F index for CRF with IDA. In conclusion, the serum sTfR concentration is a useful diagnostic tool for discrimination between IDA and ACD, and between AA and MDS-RA, and for the detection of iron deficiency in CRF patients in the Japanese population.

Adult↗
PubMed2002

[The new trend on the treatment of secondary hyperparathyroidism].

Recently various treatments for secondary hyperparathyroidism were developed. Those include a cation polymer as phosphate binder, active metabolite of vitamin D and its analogue, and various kinds of calcimimetics as Ca-sensing receptor agonist. For the secondary hyperparathyroidism refractory to those medication, direct injection of ethanol or vitamin D and its analogue is considered. All those treatments may contribute prevention and control of secondary hyperparathyroidism.

English Abstract↗
PubMed2002

[Clinical development of OCT].

OCT was first synthesized in the late 1980s, and clinical development was started in July 1991 with entry into Phase I. By the time the application for manufacturing approval was submitted, in February 1998, 15 clinical studies had been carried out, including 2 double-blind comparative studies and 5 long-term administration studies. The efficacy and safety of OCT were evaluated on the basis of clinical data obtained from totally 977 participants. OCT was found to be effective against secondary hyperparathyroidism in long-term dialysis patients, as it markedly decreased the PTH level, and showed ameliorative effects in bone tissue showing high bone turnover, and on bone metabolic markers. Adding to above clinical effects, because safety data demonstrated that there was no significant drawback except for an increase of serum calcium level, manufacturing approval was finally achieved in July 2000, under the commercial name "Oxarol injection".

English Abstract↗
PubMed2002

[Long-term clinical effect of maxacalcitol on hemodialysis patients with secondary hyperparathyroidism].

A trial on the long-term administration of 22-oxacalcitriol (maxacalcitol, OCT) was conducted among 124 patients with chronic renal failure on maintenance hemodialysis (HD) complicated with secondary hyperparathyroidism (2 degrees HPT ). In the trial, OCT was administered 3 times weekly for 26 weeks subsequent to a 26-week pre-trial. As a result, intact-parathyroid hormone (PTH) levels fell significantly after the start of administration and were well controlled for one year. The levels of markers of bone metabolism such as bone alkaline phosphatase were decreased significantly compared with those at the start of administration, suggesting a correction of high-turnover bone disease. Serum calcium (Ca) levels rose significantly following OCT administration, but were successfully maintained within a physiological range. Hypercalcemia, in 33.1% of patients, was found to resolve or ameliorate immediately after the withdrawal or dose reduction of OCT. The final doses ranged from 2.5 mg to 20 mg/HD, and the optimal dose varied among patients depending on the intact-PTH and serum Ca levels. These results clearly suggest that OCT is a highly effective drug for the treatment of 2 degrees HPT, and is an overall safe drug if the dosage is adjusted for serum Ca and intact-PTH levels.

English Abstract↗
PubMedDate not supplied

Effects of L-threo-3,4-dihydroxyphenylserine on orthostatic hypotension in hemodialysis patients.

BACKGROUND: Orthostatic hypotension (OH) is a serious complication observed in hemodialysis (HD) patients after HD as well as during the interdialytic period. L-Threo-3,4-dihydroxyphenylserine (L-DOPS) is a nonphysiological neutral amino acid that is directly converted to the neurotransmitter norepinephrine by aromatic L-amino acid decarboxylase. METHODS: A placebo-controlled double-blind study for 4 consecutive weeks and a long-term study (24-52 weeks) were conducted to evaluate the efficacy of L-DOPS for OH after HD. The drug was administered orally 30 min before the start of each HD period in both studies. Doses of 400 mg of L-DOPS or placebo were given to HD patients with OH (45 and 41 patients, respectively) in the double-blind study, and doses of 200 or 400 mg of L-DOPS were given to 74 HD patients in the long-term study. RESULTS: In the double-blind study, L-DOPS significantly ameliorated subjective symptoms related to OH, including dizziness/light-headed feeling, and malaise, throughout the interdialytic period. For 19 patients with delayed-type OH, hypotension with the lowest blood pressure recorded 10 min after standing, the decrease in blood pressure was suppressed significantly after L-DOPS treatment (10 patients) as compared with the placebo-treated group (9 patients). In the long-term study, the efficacy of L-DOPS was not attenuated, and the marked fluctuations in the plasma L-DOPS and norepinephrine levels were not noted after long-term use, without increases in incidence or severity of adverse reactions. CONCLUSIONS: These results indicate that L-DOPS is effective for improving OH-related interdialytic subjective symptoms in HD patients after short-term as well as after long-term administration.

Autonomic Nervous System Diseases↗