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Biomedical subjects

T Shinzato

Publications and source records attributed to T Shinzato.

At least 55 records · Page 3Linked to original sources
PubMed1997

Survival in long-term haemodialysis patients: results from the annual survey of the Japanese Society for Dialysis Therapy.

The prognosis for haemodialysis patients is reported to be more favourable in Japan than in Europe or North America. Consequently, evaluation of the death predictors for haemodialysis patients in Japan is of considerable interest outside Japan. The Patient Registration Committee of the Japanese Society for Dialysis Therapy annually surveys the individual patient case mix, laboratory data and important events occurring in the previous years. Thus, using case mix data and laboratory data (including Kt/V and protein catabolic rate) from the 1993 questionnaire survey and the individual patients' life/death statistics from the 1994 questionnaire survey, a logistic regression analysis was conducted on 53867 patients. The analysis indicated that important death risk predictors were: (i) advanced age, (ii) occurrence of diabetes mellitus, (iii) male sex, (iv) Kt/V lower than 1.8, (v) haemodialysis time less than 5 h, (vi) protein catabolic rate less than 0.9 g/kg/day, and (vii) percentage body weight decrease less than 4% and more than 8% during the first haemodialysis session of the week.

Adult↗
PubMed1997

Current status of renal replacement therapy in Japan: results of the annual survey of the Japanese Society for Dialysis Therapy.

Beginning in 1966, the Patient Registration Committee of the Japanese Society for Dialysis Therapy has conducted a survey once a year on renal replacement therapy in Japan. As of 1983, the survey covered the life/death of patients in the survey years, as well as the case mix of individual patients. In 1990 several laboratory variables were added to the survey items. The present report summarizes the data from the 1993 and 1994 surveys. The Committee mailed out questionnaire forms at the end of the survey year to the heads of all dialysis facilities. Survey forms were returned from 99.6% of the dialysis facilities in the 1993 survey, and from 99.8% of the facilities in the 1994 survey. Some 143709 patients were treated by renal replacement therapy in 1994 (7509 were treated by CAPD, and 131016 by extracorporeal haemopurification). The gross mortality rate was 9.5% in the same year. The mean values of the laboratory variables among 88693 patients undergoing thrice weekly haemodialysis were as follows in 1993: Kt/V, 1.31 +/- 0.30; protein catabolic rate, 1.04 +/- 0.30 g/kg/day; haemodialysis time, 4.12 +/- 0.50 h. In 1994, the variables were: predialysis serum creatinine concentration, 11.54 +/- 2.85 mg/dl; predialysis serum albumin concentration, 3.91 +/- 0.55 g/dl; predialysis haematocrit, 28.69 +/- 4.36%.

Aged↗
PubMed1997

New method to calculate creatinine generation rate using pre- and postdialysis creatinine concentrations.

The creatinine (Cr) generation rate reflects the muscle mass, a possible indicator of protein nutritional status. Thus, in this study, we developed equations for calculating the Cr generation rate. Depner and Daugirdas recently developed a method for determining the protein catabolic rate (PCR) from the pre- and postdialysis blood urea nitrogen concentrations. We modified their method to develop equations for calculating the total Cr generation rate from the measured predialysis Cr concentration and estimated postrebound concentration. The total Cr generation rate is defined as the sum of the intrinsic Cr generation rate and the extrinsic Cr generation rate (i.e., the generation rate of Cr derived from food). In the present study, the postrebound Cr concentration was estimated on the basis of postdialysis Cr concentration and the K/V for Cr. The intrinsic Cr generation rate was obtained by subtracting the extrinsic Cr generation rate, which was estimated on the basis of the PCR, from the total Cr generation rate calculated. The intrinsic Cr generation rate determined with this method was virtually the same as that obtained using the postrebound Cr concentration, the concentration immediately before the next hemodialysis (HD) session, and the PCR. The intrinsic Cr generation rate determined with the present method did not vary with changes in the HD prescription (i.e., with an increase in blood flow rate, a prolongation of the HD duration time, or a change in dialyzer membrane area). The present study also indicated that the intrinsic Cr generation rate decreased with age in both males and females.

Adult↗
PubMed1997

[Apoptosis in uremic complication].

Chronic renal failure (CRF) is often complicated by lymphopenia and sometimes by hepatic dysfunction. To elucidate the involvement of apoptosis in these complications, we analyzed Fas antigen which mediates apoptosis on peripheral blood T cells and hepatic cells. T cells from uremic patients expressed Fas with higher intensity than control T cells. When cultured in vitro, uremic T cells were shown to undergo acceleratd apoptosis in correlation with Fas expression. Immunohistological analysis of liver tissues revealed that hepatocytes in patients both with chronic hepatitis and with CRF expressed higher levels of Fas than those in patients alone with chronic hepatitis. These results suggest that T cells and hepatocytes in CRF may undergo apoptosis by the Fas system.

Apoptosis↗
PubMed1997

[A case of pulmonary sarcoidosis mimicking relapse of pulmonary tuberculosis].

A 61-year-old woman was suspected of relapse of pulmonary tuberculosis. A chest X-ray film taken at a regular health check-up suggested relapse of pulmonary tuberculosis in a 61-year-old woman. Chest X-ray revealed irregular shadow with calcification in the upper lobe of the left lung and pulmonary tuberculosis was initially diagnosed a despite a negative reaction for acid-fast bacilli on examination of her sputum and bronchial lavage. Chest CT revealed thickened bronchi and blood vessels and nodules in the lung field. Transbronchial by biopsy failed to reveal caseating epithelioid cell granulomas transbronchial lung biopsy. Past history of facial palsy, uveitis, high plasma levels of angiotensin-converting enzyme (31.6IU/L), and abnormal HRCT levels. Bronchoalveolar lavage analysis revealed an increase in lymphocytes and a CD4/CD8 ratio of 8.67. Sarcoidosis was diagnosed after a liver biopsy. This appears that HRCT findings are useful in the diagnosis of pulmonary sarcoidosis.

Diagnosis, Differential↗
PubMed1996

Purification and characterization of perlecan fragment in urine of end-stage renal failure patients.

We found a new spot on the two-dimensional electrophoresis pattern of the urine protein from hemodialysis patients. In order to identify the protein forming this new spot, the protein was purified by five steps of chromatography. It was shown that the amino acid sequence of this new protein from the N-terminal to the 20th amino acid was identical with the sequence from the 4197th to 4216th amino acid of perlecan, which is the core protein of the proteoglycan localizing in the systemic capillary basement membranes. It was also found that the molecular weight (25,000 daltons) of this new protein was comparable to the calculated molecular weight of the molecular region of the perlecan from the 4197th amino acid to the C-terminal. Lastly, it was shown that the antibodies against this new protein reacted with the perlecan produced by human fibroblasts. All these findings indicated that the new protein is a perlecan fragment.

Amino Acid Sequence↗
PubMed1996

Effective method for purification of lysozyme from human urine.

Lysozyme in the urine of a hemodialysis patient was purified in two steps: DEAE Sephadex chromatography followed by Sephacryl chromatography. The Sephacryl S-100 column chromatographed fraction showing lytic activity was proven to give one band on SDS-PAGE and to have a molecular mass of 14500, in agreement with that of lysozyme. The N-terminal amino acid sequence of this purified protein was identical to that of lysozyme. These results indicate that the protein purified was indeed lysozyme. The specific affinity of lysozyme for Sephacryl S-100 may explain the greater purity of the same protein isolated by this method.

Amino Acid Sequence↗
PubMed1996

First evidence for accumulation of protein-bound and protein-free pyrraline in human uremic plasma by mass spectrometry.

Glucose-derived advanced glycation end products (AGEs) cross-link proteins and cause various biological tissue damage. One of them, pyrraline [epsilon-2-(formyl-5-hydroxymethyl-pyrrol-1-yl) -L-norleucine], has been demonstrated by utilizing antibody to accumulate in plasma and sclerosed matrix of diabetic individuals, suggesting responsibility for diabetic complications. To elucidate the involvement of pyrraline in uremia, we examined the pyrraline levels in patients with chronic renal failure by a mass spectrometric approach. Here we show that protein-free pyrraline as well as pyrraline with binding protein are significantly increased in non-diabetic uremic plasma compared to healthy subjects. Our results suggest that circulating pyrraline could be a substance contributing to complications in uremia.

Blood Proteins↗
PubMed1996

Successful repair of intimal dissection following coronary angioplasty with a 48-hour inflation of spiral inflation coil and local delivery of heparin.

We report on an unusual patient with a threatened occlusive dissection, in whom prolonged (48-hr) inflation of a balloon catheter with localized heparin infusion proved successful. This intracoronary infusion catheter maintained distal coronary flow on a unique spiral coil design, and may provide an alternative or a bridge to emergency operation or stent implantation.

Aged↗
PubMed1996

Enhancement of postischemic myocardial stunning by calcium overload in hearts of diabetic rats.

The effects of Ca2+ concentration on postischemic myocardial stunning were studied in isolated working hearts of rats with streptozotocin-induced diabetes and of age-matched control rats. During reperfusion after 10 min of ischemia, hearts from control rats showed complete recovery of cardiac function of Ca2+ concentrations of 1.25, 1.88, and 2.50 mmol/L, while the recovery of diabetic rats was decreased only at a Ca2+ concentration of 2.50 mmol/L. Although myocardial Na+ and Ca2+ concentrations were comparable between control and diabetic rats, only diabetic rats showed increases in myocardial concentration of Na+ during ischemia and Ca2+ during reperfusion at a Ca2+ concentration of 2.50 mmol/L. Results suggest that diabetic rat hearts are vulnerable to postischemic stunning via an overload of calcium.

Animals↗
PubMed1996

Effect of gliclazide on the functional response to calcium in diabetic rat heart.

1. The cardiac functional response to extracellular Ca2+ in isolated working hearts was evaluated in streptozotocin-induced diabetic rats treated or not treated with gliclazide. 2. Gliclazide treatment of diabetic rats allowed a partial recovery of the body weight decrease, but not of the hyperglycemia nor insulinopenia. 3. The cardiac mechanical response of diabetic rats was altered, especially at high Ca2+ concentration, and 6-week gliclazide treatment restored the dysfunction close to the control values. 4. The results suggest that gliclazide treatment restores the cardiac function of chronic diabetic rats partly through modulating the Ca2+ metabolism.

Animals↗
PubMed1996

Cardioprotective effects of troglitazone in streptozotocin-induced diabetic rats.

Troglitazone, a new oral antidiabetic agent, shows hypoglycemic effects in insulin-resistant animal models and humans. This study was conducted to evaluate the effects of troglitazone on the heart of diabetic animals. Streptozotocin (STZ)-induced diabetic rats and age-matched controls were treated with troglitazone as a 0.2% food admixture for 6 weeks. Basal and postischemic cardiac functions at 14 weeks of age were then examined in isolated working heart. Troglitazone treatment did not attenuate the insulinopenia and hyperglycemia of diabetic rats, but it partially improved the hypertriglyceridemia. Troglitazone treatment partially restored the basal heart rate and cardiac work of diabetic rats to nearly control values. Troglitazone also improved the postischemic functional deficits of diabetic rats: heart rate (untreated 61% of baseline at 30-minute reperfusion v treated 92%, P < .001), left ventricular (LV) developed pressure (54% v 94%, P < .001), peak positive ([LV + dP/dt] 54% v 93%, P < .001) and negative ([LV -dP/dt] 53% v 94%, P < .001) first derivative of LV, and cardiac work (44% v 98%, P < .001). Diabetic animals showed ultrastructural damage including disarray of sarcomere, disorganization of mitochondrial matrix, cytoplasmic vacuolization, and invagination of nuclear membrane; these were partially normalized by troglitazone treatment. Our results suggest that troglitazone treatment has a cardiprotective effect on the basal and postischemic cardiac function of STZ-induced diabetic rats.

Animals↗
PubMed1996

Alternate repetition of short fore- and backfiltrations reduces convective albumin loss.

An effective therapeutic means to remove relatively large polypeptide uremic toxins seems to be a hemofiltration (HF) or hemodiafiltration (HDF) employing a larger-pore membrane, that is, a protein-permeable membrane. With either method, however, a significant amount of albumin will be lost into the ultrafiltrate or dialysate. Now, repetition of alternate short fore- and backfiltrations may prevent the development of the ultrafiltration-induced higher albumin concentration on the membrane surface (protein concentration polarization), where a single forefiltration time is shorter than the time needed for completion of protein concentration polarization. Since the albumin concentration on the protein-permeable membrane surface will be one of the determinants of albumin loss by convection, such HDF treatment may reduce protein loss into the dialysate. To examine this assumption, we alternately repeated short and rapid fore- and backfiltrations (push/pull HDF) through a protein-permeable membrane, each less than 1 second in duration and at each filtration volume of 15 ml, where a pyrogen-free dialysate was supplied. The present results indicated that the albumin amount lost by push/pull HDF was approximately one-third of that by conventional HDF. Nevertheless, the reduction rates of beta 2-microglobulin and myoglobin were significantly greater by push/pull HDF than by conventional HDF.

Blood Proteins↗
PubMed1996

Monocyte/macrophage response to beta 2-microglobulin modified with advanced glycation end products.

We recently found that acidic beta 2-microglobulin (beta 2m), a major isoform of beta 2m in amyloid fibrils of patients with dialysis-related amyloidosis (DRA), contained early Amadori products and advanced glycation end products (AGEs) formed nonenzymatically between sugar and protein. Further analysis revealed that acidic beta 2m induces monocyte chemotaxis and macrophage secretion of bone-resorbing cytokines, suggesting the involvement of acidic beta 2m in the pathogenesis of DRA. Acidic beta 2m, however, is a mixture of heterogeneous molecular adducts due to various types of modification. In the present study, we investigated the modification responsible for the biological activity of acidic beta 2m toward monocytes/macrophages. The presence of a fair amount of beta 2m species with deamidation was detected in acidic beta 2m isolated from urine of non-diabetic long-term hemodialysis patients, but deamidated beta 2m had no biological activity. In contrast, normal beta 2m acquired the activity upon incubation with glucose in vitro. Among the glycated beta 2m, the pigmented and fluorescent beta 2m that formed after a long incubation period, that is, AGE-modified beta 2m, exhibited biological activity, whereas beta 2m modified with Amadori products, major Maillard products in acidic beta 2m, had no such activity. These findings suggest that AGEs, although only a minor constituent of acidic beta 2m, are responsible for monocyte chemotaxis and macrophage secretion of cytokines, implicating the contribution of AGEs to bone and joint destruction in DRA.

Adult↗
PubMed1996

Advantage of monitoring skin vibration as an index of arteriovenous fistular blood flow.

Monitoring of the skin vibration is disturbed little by environmental noise. Therefore, the skin vibration is more relevant than bruit on the skin by means of monitoring the fistular blood flow. Frequency analysis of the skin vibration generated by an internal arteriovenous fistula indicated two peaks of power spectral density (PSD), one in the frequency range of 4-10 Hz and the other from 100-300 Hz. The analysis of the skin vibration generated by an external fistula, however, showed only one peak in the range of 4-10 Hz and a moderate flat PSD level in the range of 100-300 Hz. The PSD level in the range of 100-300 Hz decreased dramatically or disappeared when the fistular blood flow diminshed or ceased. Therefore, the optimal frequency for monitoring skin vibration may be the range of 100-300 Hz.

Arteriovenous Fistula↗