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Biomedical subjects

T Tsutsui

Publications and source records attributed to T Tsutsui.

At least 163 records · Page 9Linked to original sources
PubMed1994

[Association of cell cycle and protein kinase C with the expression of cytoskeletal protein in cultured rat mesangial cells].

We conducted a study to investigate whether expression of the contractile proteins in cultured rat mesangial cells (MC) was associated with the cell cycle and protein kinase C (PKC). When growth-arrested MC were stimulated with 100 nM phorbol myristate acetate (PMA) for 24 hours, an increased expression of smooth muscle alpha-actin and vimentin was detected by immunocytochemistry. A proportion of the S- and G2/M-phase in MC was increased in accordance with the enhanced expression of contractile proteins on flow cytometry. Immunoblot analysis revealed that 100 nM PMA stimulated expression of alpha-actin and vimentin as a single band. These results indicate that expression of contractile proteins, such as alpha-actin and vimentin, is dependent on the cell cycle and PKC, suggesting a phenotypic change in which MC assume smooth muscle cell characteristics.

Animals↗
PubMed1994

[Comparison of the clinical usefulness of the two types of combined spinal epidural needles].

The clinical usefulness of Combined Spinal-Epidural (CSE) needles, Portex Spinal/Epidural set (P needles) and Hakko Disposable Needles set type H (H needles) was compared on 30 patients undergoing elective orthopedic lower limb surgeries. Although the calibers of the epidural needles were a little different, both needles were introduced quite easily in the epidural space. The spinal needles were inserted successfully to the subarachnoid space in 27 out of 30 cases by the P needles and 23 out of 30 cases by the H needles. The average trial times for successful insertion of the spinal needles were 1.3 and 2.6 by the P needles and the H needles, respectively. this was statistically significant (P < 0.05). Adequate spinal anesthesia was established in 26 patients (87%) and 19 patients (63%) by the P needles and the H needles, respectively. One case of the accidental location of the epidural catheter in the subarachnoid space was observed in each group. As the CSE device, the P needles were more sophisticatedly designed for easier insertion to the subarachnoid space than the H needles.

Adolescent↗
PubMed1994

Establishment and characterization of an immortalized bovine glomerular endothelial cell line.

Bovine subcultures (second passage) of glomerular endothelial cells (GEN) isolated from one-year-old kidney were successfully transfected by recombinant plasmids containing the simian virus (SV)-40 T antigen (Tag) using a lipofectin-mediated procedure. One cell clone was selected, propagated and characterized. This clone can be grown in RPMI 1640 medium supplemented with 10% fetal calf serum. The advantage of this cell line is the cultivation of bovine GEN without the addition of fibroblast growth factor or a coating of fibronectin or gelatin on the culture plate. More than 80 passages were achieved and the doubling time was 32 h. The Tag was easily identified in transfected-GEN by indirect immunofluorescence. These cells weakly expressed factor VIII-related antigen, slightly took up acetylated-low density lipoprotein and secreted a detectable amount of angiotensin-converting enzyme. Immunocytochemical staining for UAE-1 was also positive. Moreover, oncoproteins, such as Ki-67 and p53, were expressed in these cells. Cell cycle analysis by flow cytometry revealed that the percentages of G1, S, and G2/M stages in cycling transfected-GEN culture in RPMI 1640 medium supplemented with 10% fetal calf serum were 34%, 52.9%, and 13.1%, respectively. The conditioned medium from confluent transfected-GEN stimulated [3H]thymidine incorporation into glomerular mesangial cells. This cell line may provide a useful tool for examining modulators of mesangial cell growth. Thus this cell line is the first immortalized bovine GEN that retain the morphologic, phenotypic, and functional characteristics of bovine GEN.

Animals↗
PubMed1994

[Influence of ionized calcium concentration during cardiopulmonary bypass on pediatric cardiac surgery].

Changes of serum ionized calcium concentration (Ca2+) during cardiopulmonary bypass (CPB) were analyzed in 30 pediatric cardiac patients less than 15 kg body weight. Ca2+ decreased suddenly after the start of CPB, and it gradually increased to the normal value. Citrate added to the stored blood for priming and its metabolism might play a role in these changes of Ca2+. Addition of adequate volume of calcium chloride to the priming prevented sudden decrease of Ca2+. Although addition of citrate before aortic declamp effectively decreased Ca2+ and may prevent reperfusion cardiac injury associated with hypercalcemia, there were no correlation between predeclamp level of Ca2+ and serum CPK and GOT levels.

Body Weight↗
PubMed1994

Identification of GTP-binding proteins in human glomeruli.

The localization of GTP-binding proteins (G-proteins) in human glomeruli was examined using immunohistochemistry and immunoblotting. Immunohistochemical staining for G-protein subunits demonstrated the existence of Gs alpha, Gi alpha and Go alpha proteins in the glomeruli. Moreover, immunoblots further revealed Gs alpha (52 kD), Gi alpha 1/2 (40-41 kD), Gi alpha 3 (40 kD) and Go alpha (39 kD) in the glomerular membranes. The predominant subspecies of Gs was a 52-kD protein, and Go alpha was detectable in the smallest amounts of the G-protein subunits. However, immunoblots failed to demonstrate detectable amounts of G-proteins in cytosolic extracts. This is the first report that characterizes G-protein subunits in human glomeruli. Further study is required to determine the roles of G-proteins in signal transductions in human glomeruli.

GTP-Binding Proteins↗
PubMed1994

[Significance of membrane attack complex inhibitory factor expression in cultured human glomerular epithelial cells].

Membrane attack complex (MAC) inhibitory factor (MACIF) is a 20-kD membrane protein that inhibits MAC formation on homologous cells. Until recently, a functional role of MACIF had been demonstrated in erythrocytes. Therefore, we have focused on the fact that glomerular epithelial cells (GECs) are the primary target of MAC-mediated damage in rat Heymann's nephritis model of human membranous nephropathy. Using immunocytochemistry and western blotting we have shown that MACIF is expressed in cultured human GECs. Phosphatidyl-inositol (PI)-phospholipase C (PLC) reduced MACIF expression in these cells, suggesting that MACIF is a PI-linked membrane protein in GECs. In addition, we elucidated that MACIF protects GECs against complement-mediated lysis. These findings suggest that MACIF expressed on GECs plays an important role in the protection of GECs against complement mediated-cellular damage in vivo.

CD59 Antigens↗
PubMed1993

Assessment of high-energy phosphorus compounds in the rat kidney by in situ 31P nuclear magnetic resonance spectroscopy: effect of ischemia and furosemide.

31P nuclear magnetic resonance (NMR) spectroscopy of the in situ rat kidney was performed by a surface coil method, and the effects of ischemia and furosemide infusion were assessed. 31P NMR spectra of the kidney subjected to 30 min of ischemia returned completely to the pre-ischemic level after 60 min of reperfusion. But the 31P NMR spectra after 60 min of ischemia did not recover, even after 120 min of reperfusion. Levels of beta-ATP and inorganic phosphate (Pi) decreased and the chemical shift of Pi increased after intravenous infusion of furosemide. This increase in chemical shift might signal an alkalotic change in intracellular pH. Furosemide infusion prior to ischemia is thought to protect the kidney from injury induced by 60 min of warm ischemia. The chemical shift of Pi returned to the pre-ischemic level earlier than beta-ATP and Pi. In conclusion, according to the findings of 31P NMR spectroscopy, furosemide infusion prior to ischemia may be effective in protecting the kidney against ischemic injury. But the change in Pi peak and the causes of the dissociation of Pi and beta-ATP should be examined further.

Animals↗
PubMed1993

Cell cycle dependence of cytotoxicity and clastogenicity induced by treatment of synchronized human diploid fibroblasts with sodium fluoride.

To study the cell cycle dependence of cytotoxicity and clastogenicity of sodium fluoride (NaF), synchronized human diploid fibroblasts were treated with NaF during different phases of the cell cycle and analyzed. Exponentially growing cells were synchronized by the following two procedures. (1) The cells were synchronized at G0/G1 phase by a period of growth in medium containing 1% serum (low serum medium). (2) The cells were synchronized at the G1/S boundary by growth in low serum medium, followed by hydroxyurea treatment (Tsutsui et al., 1984a). Synchronized cells were treated with NaF for 3 h during the G1 phase or G2 phase, and for each of three 3-h periods during the S phase which lasted 9 h. Cytotoxicity, as determined by a decrease in colony-forming ability, was dependent upon the phase of the cell cycle during which NaF treatment was administered. The highest lethality was induced in cultures treated with NaF during the first 3 h of S phase (early S phase). Moderate lethality was observed when the cultures were treated with NaF during the second or third 3 h of S phase (middle or late S phase, respectively), or G2 phase. Little lethality was observed in cultures in G1 phase. Inducibility of chromosome aberrations of the cells following treatment with NaF was also dependent upon the phase of the cell cycle. A significant increase in the incidence of chromosome aberrations was observed only in cultures treated with NaF during early and/or middle S phases of cell cycle. These results suggest that cytotoxicity and clastogenicity of NaF to cultured human diploid fibroblasts are cell cycle dependent, and that the cells in early and middle S phases are more sensitive to the effects.

Cell Cycle↗
PubMed1993

Analysis of hprt gene mutation following anti-cancer treatment in pediatric patients with acute leukemia.

We evaluated the genotoxic effect of cancer therapy on somatic cell mutation by isolating 6-thioguanine-resistant mutants in peripheral lymphocytes. The study population comprised 45 children with acute lymphoblastic leukemia (ALL), 13 children with acute myelogenous leukemia (AML) and 28 age-matched healthy controls. The geometric mean mutant frequency for ALL patients was 7.8 x 10(-6), which was significantly higher than that for AML patients (1.7 x 10(-6)) or for healthy controls (1.1 x 10(-6)). Fifteen patients with ALL showed a high mutant frequency above 10 x 10(-6), although 10 of them had completed their treatment at least 24 months earlier. Moreover, repeated measurements of mutant frequency at intervals of 12 or more months revealed that the values were very stable. Structural hypoxanthine-guanine phosphoribosyl transferase (hprt) gene alterations, as determined by Southern blot analysis, were seen in 23% (12/52) of mutant clones derived from ALL patients, but not in those from the controls. These results suggest that intensive anti-cancer therapy of children may produce persistent somatic mutations, which could be related to the appearance of second neoplasms.

Adolescent↗
PubMed1993

A reconsideration of surgery for mitral stenosis based on the extent of valvular distortion shown by two-dimensional echocardiography preoperatively.

A twelve-year follow-up study was carried out with 98 consecutive patients operated on for pure mitral stenosis with open mitral commissurotomy (OMC) or valve replacement with porcine valves (MVR). Each patient had the extent of valve distortion diagnosed preoperatively by two-dimensional echocardiography as either grade I of the dome-formation type, grade II of the intermediate type, or grade III of the mass-formation type. Thirty grade I patients and 24 grade II patients underwent OMC and 44 grade III patients received MVR. The long-term survival and reoperation rates were significantly poorer with grade II than grade I patients and there was no statistical significance between grades II and III. However, the clinical conditions set by NYHA are significantly worse in grade II than in grade III. This can be clearly explained by the fact that the left atrial volume decreasing ratio (LAVDR) in the latest period, which was measured in patients with more than 7 years survival, remained nearly at the early postoperative value in grade III, while the LAVDR of grade II at the latest period grew worse and became insignificantly different from the preoperative values. This study clearly shows that when OMC is applied to grade II patients, frequent reoperations might be necessary because of poor hemodynamic conditions. Thus, it might be better to adopt MVR rather than OMC with grade II patients with moderately distorted mitral valves.

Actuarial Analysis↗
PubMed1993

Laparoscopic adrenalectomy for primary aldosteronism: a new operative method.

From January 17, 1992 to January 16, 1993, laparoscopic adrenalectomy was performed in 7 patients (3 men, 4 women) with primary aldosteronism ranging in age from 35 to 65 years (mean 48.7 years). Five of the adrenal lesions were on the left side and two were on the right. Five to six trocar-sheath units were used, and adrenal tumors were successfully removed with adjacent normal adrenal glands in all patients. The operative time ranged from 165 to 572 min (mean 302 min), operative blood loss was between 50 and 450 ml (mean 217.2 ml), and there was no major complication. In conclusion, laparoscopic adrenalectomy is a safe alternative operative method for primary aldosteronism, although application of this technique to other types of adrenal lesions remains to be examined.

Adrenal Gland Neoplasms↗
PubMed1993

Ability of peroxisome proliferators to induce cell transformation, chromosome aberrations and peroxisome proliferation in cultured Syrian hamster embryo cells.

Di(2-ethylhexyl)phthalate (DEHP), a commonly used plasticizer, induces proliferation of peroxisomes in liver cells and causes hepatocellular carcinomas when chronically administered in the diet to rodents. To examine possible mechanisms for DEHP-associated cancer, we have measured induction of morphological transformation, chromosome aberrations and peroxisome proliferations of cultured Syrian hamster embryo (SHE) cells by DEHP and other peroxisome proliferators. Morphological transformation of SHE cells was weakly induced by treatment for 48 h with DEHP and its metabolite mono(2-ethylhexyl)phthalate (MEHP). The transformation frequency by DEHP was enhanced by exogenous metabolic activation using rat liver postmitochondrial supernatants. Treatment for 24 h with DEHP resulted in chromosome aberrations of the cells only in the presence of exogenous metabolic activation. 2-(p-chlorophenoxy)-2-methylpropionic acid ethyl ester (clofibrate), a widely used hypolipidemic drug, failed to induce morphological transformation or chromosome aberrations of SHE cells. Treatment with [4-chloro-6-(2,3-xylidino)-2-pyrimidinylthio] acetic acid (WY-14,643), which is a more potent carcinogen than DEHP or clofibrate, elicited a lower frequency of morphological transformation than DEHP in the presence of exogenous metabolic activation but was more active than DEHP at inducing chromosome aberrations. Similar levels of peroxisome proliferation, as determined by an intensity of diaminobenzidine staining, were observed in cultures treated for 2 h with DEHP, MEHP, clofibrate or WY-14,643. These results suggest a possible involvement of genetic damage by DEHP metabolites in the induction of cell transformation of SHE cells by DEHP; however, no clear relationship among induction of peroxisome proliferation, carcinogenicity in vivo and cell transformation was observed. Although the ability to induce cell transformation and chromosomal mutations is not adequate to explain the carcinogenicity of this class of compounds, these biological effects may be contributory to the carcinogenic activities of peroxisome proliferators.

Animals↗
PubMed1993

Value of urinary endothelin-1 in patients with primary vesicoureteral reflux.

By using a radioimmunoassay specific for endothelin-1 (ET-1), we measured urinary excretion of ET-1-like immunoreactivity (LI) in 63 spot urine samples of 48 patients with primary vesicoureteral reflux (VUR). And also, urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG), beta 2-microglobulin (beta-2-MG), microalbumin (Alb) and creatinine (Cr) were measured. There was no significant correlation in any of the pairs ET-1 and NAG, ET-1 and beta 2-MG, and ET-1 and Alb. Comparing the grade of reflux according to the International Classification with urinary ET-1, urinary ET-1/Cr levels in patients with grade 2, 3 and 4 VUR were higher than normal, and the ratio of more than normal urinary ET-1/Cr increased in proportion to the grade of reflux, but it conversely decreased in grade 5. In conclusion, urinary ET-1 may be an indicator of renal tubular injury in patients with primary VUR, and its meaning may be different from conventional urinary parameters.

Acetylglucosaminidase↗
PubMed1993

Evaluation of upper urinary tract dynamics by diuresis renography in patients receiving urinary reservoir operation. Comparison of full and empty reservoir.

Upper urinary tract dynamics was evaluated using diuresis renography during full and empty reservoir in 14 patients (11 men, 3 women, 13-70 years old) with intestinal urinary reservoir or intestinal bladder augmentation. Types of operation were Mainz pouch urinary diversion 5, Mainz neobladder to urethra, 5, Kock pouch urinary diversion 2, and Mainz bladder augmentation 2. Diuresis renography was performed using 99mTc-DTPA and furosemide during full and empty reservoir, and several parameters (Tmax, T75, T50, GFR) in addition to the patterns of renogram were evaluated. In the normal control, none of the parameters of the diuresis renogram with full bladder differed from those with empty bladder. In 5 of 14 patients, abnormal waves on cystometry (CMG) were found, and in 4 of these 5 patients, the patterns of diuresis renogram of full reservoir were worse than those of empty reservoir. However, the patterns of diuresis renogram of full reservoir were not different from those of empty reservoir in 9 patients without abnormal waves on CMG. In conclusion, renal injury may easily occur in patients with intestinal reservoir and abnormal waves on CMG.

Adolescent↗
PubMed1993

Successful fibrinolytic therapy using tissue plasminogen activator in acute renal failure due to acute thrombosis of bilateral renal arteries.

A 46-year-old housewife with regurgitation of mitral valve developed acute renal failure due to acute thrombosis of bilateral renal arteries after cardiac catheterization. A regional fibrinolytic therapy using transarterial infusion of tissue plasminogen activator (t-PA) was performed at 8 h after the onset, and was successful. She could be taken off hemodialysis 2 weeks after the fibrinolytic therapy, and could be successfully operated on with mitral valve replacement 7 months after that. Three years after mitral valve replacement, her serum creatinine was 148 mumol/l. This is the longest follow-up case after regional transarterial fibrinolysis of acute thrombosis of renal artery using t-PA, and this therapy is a safe and good one for acute thrombosis of renal artery.

Acute Disease↗
PubMed1993

Pituitary response of cryptorchid dogs to LH-RH-analogue before and after sexual maturation.

An LH-RH-analogue (LH-RH-A) was administered to 5 cryptorchid (CR) and 6 normal beagles before and after sexual maturation and peripheral plasma LH and testosterone levels were measured. The response patterns of plasma LH levels for LH-RH-A in the CR dogs were similar to those in the normal dogs before and after sexual maturation. It was therefore demonstrated there is little difference in pituitary response to LH-RH-A in the CR and normal dogs. However, the maximum levels of testosterone in the CR dogs were generally lower than those in the normal dogs.

Animals↗
PubMed1993

Ovarian response to hCG in the postweaning sow.

Five non-cyclic postweaning sows were given intramuscularly 1,000 IU of hCG on day 2 (4 sows) and day 36 (1 sow) after weaning. Single or multiple follicular cysts were developed in ovaries in all cases. Plasma E2 fluctuated at low levels in 4 of 5 sows resulting in silent heat. The sows which exhibited neither estrus nor ovulation after hCG administration did not display any preovulatory LH surge, and plasma progesterone levels remained low (< or = 1 ng/ml). These results suggest that abnormal follicular growth or impairment of the ovulation process as a consequence of unsatisfactory LH release after hCG treatment in swine with ovarian inactivity may promote the formation of ovarian cysts.

Animals↗