Biomedical subjects

S Ebisuno

Publications and source records attributed to S Ebisuno.

At least 37 records · Page 2Linked to original sources

PubMed1995

Adhesion of calcium oxalate crystals to Madin-Darby canine kidney cells and some effects of glycosaminoglycans or cell injuries.

The present investigation studied the quantitative adhesion of calcium oxalate monohydrate (COM) crystals to the surface of Madin-Darby canine kidney cells, which exhibit many characteristics of renal cortical collecting tubule cells. COM crystals adhered to the cell surface, and the attachment showed a time and concentration dependency with plateau. The results suggested that the attachment of microcrystals to the cortical tubular cell might be one of the earliest processes in the formation of kidney stones. Pretreatment with glycosaminoglycans significantly reduced the adherent crystals. Injuries to the Madin-Darby cells induced by 0.1 M HCl and gentamicin resulted in significant decreases of COM crystal adhesion to the cell surface. It was suggested that urinary glycosaminoglycans might play some critical role in preventing crystal adhesion to these cellular membranes and that cell injuries might not be essential for the attachment of microcrystals to the tubular cells.

Animals↗

PubMed1995

[A case of clear cell adenocarcinoma of the female urethra].

A case of clear cell adenocarcinoma arising from the female urethra is described. Histologically, solid and glandular areas consisted of clear cells. The tumor cells were stained positively with antibodies to prostate specific antigen (PSA) and prostatic acid phosphatase (PAP), suggesting that the clear cell adenocarcinoma arises from the female paraurethral duct, rather than embryonic remnant.

Adenocarcinoma, Clear Cell↗

PubMed1994

Oxalate transport in a line of porcine renal epithelial cells--LLC-PK1 cells.

The present studies examined oxalate handling in LLC-PK1 cells, an epithelial cell line of porcine origin. These cells appear to express transport systems for oxalate, as evidenced by the fact that uptake was saturable, time dependent and sensitive to the anion transport inhibitor DIDS (4,4'-diisothiocyanostilbene-2,2'-disulfonic acid). Oxalate uptake in these cells was also affected by the presence of certain inorganic anions (Cl-, SO4(2-), or HCO3-) but not by organic anions (para-aminohippurate, urate, malate, phenylsuccinate, succinate). This uptake was Na independent and unaffected by changes in membrane potential but was affected by external pH, with acidic pH stimulating and alkaline pH inhibiting oxalate accumulation. These findings suggest that LLC-PK1 cells express oxalate transporters similar to those observed in the mammalian renal cortex. Further studies using these cells may prove useful in defining the conditions that govern transcellular oxalate flux in renal epithelial cells.

Animals↗

PubMed1994

Polarized distribution of oxalate transport systems in LLC-PK1 cells, a line of renal epithelial cells.

Although oxalate is a major component of kidney stones, the factors affecting renal oxalate handling are poorly understood. This uncertainty stems in part from complexities inherent to available preparations; thus the present studies examined oxalate handling in a simpler model system, LLC-PK1 cells, an epithelial cell line of porcine origin. Initial studies on monolayers in dishes demonstrated that these cells accumulate oxalate via a process or processes sensitive to the anion transport inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS). Subsequent studies using LLC-PK1 monolayers on membrane filters examined the characteristics and distribution of these transporter(s). At the apical surface, DIDS-sensitive uptake was sensitive to [Cl-] but not [SO4(2-)] or [HCO3-] and was unaffected by alterations in pH or membrane potential. At the basolateral surface, oxalate uptake was [Cl-] insensitive but markedly affected by variation in pH, [SO4(2-)], or [HCO3-]. Uptake at the two membrane surfaces was also differentially affected by transport inhibitors and organic acids. Thus LLC-PK1 cells appear to express unique transporters at each membrane surface: oxalate/Cl- exchange at the apical surface and oxalate/SO4(2-) (or HCO3-) exchange at the basolateral surface.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗

PubMed1994

A case of Klebsiella pneumoniae endophthalmitis metastasized from prostatitis.

A case of Klebsiella pneumoniae endophthalmitis metastasized from prostatitis is reported. A 58-year-old alcoholismic man with diabetic diathesis suffered from endophthalmitis which required enucleation of his left eye, when he interrupted the treatment of prostatitis. Metastatic bacterial endophthalmitis from urinary tract infection is rare.

Endophthalmitis↗

PubMed1993

Effect of urinary macromolecules on aggregation of calcium oxalate in recurrent calcium stone formers and healthy.

The inhibitory activity of urinary macromolecules on the aggregation of calcium oxalate crystals was studied using an aggregometer originally devised to measure thrombocyte aggregation capacity by means of the optical turbidity at 660 nm. The macromolecular fraction of the urine (molecular weight above 5000) of recurrent calcium stone formers showed much less inhibitory activity than that of healthy controls (P < 0.05). It was speculated on the basis of the results of gel filtration that there were some proteins (molecular weight about 10,000-30,000) which had inhibitory activities for the aggregation of calcium oxalate. This gives support to the assumption that macromolecules are important during the phase of aggregation of calcium oxalate crystals.

Calcium Oxalate↗

PubMed1993

[Active uptake of oxalate in a renal tubular cell line (LLC-PK1)].

The oxalate uptake was studied in LLC-PK1 cells, an epithelial cell line originated in proximal tubular cells of porcine kidney. It was clear that the cells contain an oxalate exchanger highly sensitive to 4,4-diisothio-cyanostilbene-2-' disulfonic acid (DIDS). The uptake was inhibited by the addition of inorganic anions (chloride, sulphate and bicarbonate) to the reaction system, but was unaffected by sodium ion. The data suggest the possibility that it should be consistent with at least two transport systems for oxalate in LLC-PK1 cells, a SO4-/oxalate/HCO3- exchanger and a Cl-/oxalate exchanger.

4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfo↗

PubMed1993

[Some effects of pH, diuretics and organic acids on the uptake of oxalate in a renal tubular cell line (LLC-PK1)].

The effects of changes in extracellular pH and treatments with diuretics or some organic acids on the uptake of oxalate were studied in an epithelial cell line of renal origin (LLC-PK1 cells). The oxalate uptake into the cells exhibited a marked sensitivity to extracellular, pH, in the present results with acidic pH stimulating and alkaline pH inhibiting the DIDS sensitive uptakes. The uptake of oxalate was clearly inhibited by DIDS, proportionally to the concentrations from 10 microM to 1 mM. Furosemide, chlorothiazide, probenecid and acetazolamide inhibited the oxalate uptake significantly. Probenecid has the most potency on the inhibition of the uptake in high concentrations, and acetazolamide needed a high concentration for the small effect. However, allopurinol has no effect on the uptake as well as dicarboxylates (malate, succinate and phenyl succinate) and organic acids (urate and para-amino hippurate). We discussed the mechanisms of the inhibition against the oxalate uptake concerning with each drug. It was suggested that probenecid may inhibit the oxalate carriers directly, while furosemide, chlorothiazide and acetazolamide may inhibit then by the direct actions and some secondary effects which are provided by those drugs.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗

PubMed1993

[Adhesion of calcium oxalate crystal to Madin-Darby canine kidney cells: quantitative determination and effects of glycosaminoglycans (GAG) and cell injuries on adhesion].

The present investigation was designed to study adhesion of calcium oxalate crystals on the surface of intact MDCK cells quantitatively, and to estimate the effects of glycosaminoglycans (GAGs) and cell injuries on these adhesions. Calcium oxalate monohydrate (COM) crystals adhere to the cell surface by an active force, and the attachment is in a time and concentration dependency with plateau. Pre-treatments with low concentration of GAGs (chondroitin sulphate C, hyaluronic acid, heparan sulphate, heparin and sodium pentosan polysulphate) produce significant reductions of the adhesion. There are significant decreases of the adhesions with pre-treatments of Triton-X100, 0.1 N HCl and gentamicin. These phenomena might be induced by some alterations of cell surface structures or characters. The current quantitative system on MDCK cells should serve as a useful model for the investigations of interactions with crystals and tubular cells. Our studies may also support the hypothesis of attachment of microcrystals to the cellular membrane, which is one of the most important and the earliest process of the pathophysiology of kidney stone.

Animals↗

PubMed1993

[Inhibitory activity of urinary macromolecule upon calcium oxalate crystal aggregation using an aggregometer].

We studied inhibitory activity of urinary macromolecule upon the calcium oxalate crystal aggregation using an aggregometer. We have developed an aggregometric assay method to measure the anti-aggregation ratio of calcium oxalate crystals in vitro. The macromolecular fraction of urine with a molecular weight above 5,000 was isolated by PD-10 (Sephadex G-25M, Pharmacia) and made up to three-fold by Centriprep Concentrator (Amicon). The urinary macromolecular substances of recurrent calcium stone formers showed much less inhibitory activity than those of healthy controls. There were no significant relationships between the anti-aggregation activity and the concentration of urinary proteins and other parameters concerning with stone diseases. It was speculated that some proteins, molecular weight about 10,000-30,000, might inhibit the aggregation vigorously based on the result of gel filtration (Superrose 12 HR, 20/50, Pharmacia) technique used in a healthy man's 24 hours urine. Thus, it supports that some urinary macromolecules are important during the phase of aggregation of calcium oxalate crystals, and that the feeble activity to present the aggregation may be one of the cause of calcium oxalate stone formation.

Adult↗

PubMed1993

[Use of a rate responsive pacemaker in sick sinus syndrome].

In this study of 10 patients with sick sinus syndrome, we examined the benefits of a single-chamber ventricular pacing system that utilizes a sensor to detect the QT interval and then adjusts the heart rate. Changes in exercise tolerance capacity and cardiac function were evaluated when the pacing mode was changed from rate-variable mode (VVIR) to fixed-rate mode (VVI). Anaerobic threshold (AT), peak VO2 and cardiac output were measured in VVIR, during short-term VVI(VVI-S), which occurred two hours after the pacing mode was changed, and during long-term VVI (VVI-L), which occurred one month after the pacing mode was changed. 8 of 10 cases (80%) had their own beats during exercise. The AT and peak VO2 during VVI-S were not different from those during VVIR. However, AT and peak VO2 during VVI-L were significantly lower than those during VVIR pacing. (Respectively, 11.7 +/- 2.4 vs. 16.4 +/- 3.3, p < 0.01; 21.5 +/- 5.9 vs. 24.6 +/- 6.2, p < 0.01). At AT and peak VO2, there were no differences in cardiac output between VVIR and VVI-S, or between VVIR and VVI-L(NS). Physiologic changes in heart rate and cardiac output after exercise during VVIR were greater than those during VVI pacing. The present study suggests the above-mentioned changes after exercise effect, oxygen consumption in the peripheral circulation, which might lower exercise tolerance capacity in the chronic phase. The rate-variable pacing mode might improve exercise tolerance capacity and may be of benefit for patients with sick sinus syndrome.

Aged↗

PubMed1991

Results of long-term rice bran treatment on stone recurrence in hypercalciuric patients.

A series of 182 calcium stone formers with idiopathic hypercalciuria underwent treatment with rice bran for 1 to 94 months. Urinary calcium excretion was considerably reduced, but there was some increase in urinary phosphate and oxalate. Urinary excretion of magnesium and uric acid, serum calcium, magnesium, phosphate, uric acid, parathyroid hormone (PTH) and ALP was unaffected. There were no obvious changes in serum iron, zinc and copper even when patients were treated for long periods. Rice bran was well tolerated in almost all cases and there were no serious side effects; 49 patients have undergone treatment for more than 3 years (average duration of administration 5.09 years). The frequency of new stone formation was drastically reduced (individual stone formation rate (no./year) from 0.720 +/- 0.533 to 0.125 +/- 0.204; group stone formation rate (no./patient-year) from 0.721 to 0.120) compared with the 3-year period before treatment. During treatment, 61.2% of patients remained in remission. Although rice bran therapy should be effective in correcting absorptive hypercalciuria, there may be limits to the overall ability of rice bran monotherapy to prevent recurrence.

Calcium↗

PubMed1991

[An enzymatic determination of serum citrate with citrate lyase].

A method for the enzymatic determination of the serum citrate using citrate lyase is described. The optimum pH was equal to or higher than 8.6. Prior to the determination of the serum citrate, the samples were deproteinized with perchloric acid. After the precipitation of the proteins, potassium hydroxide was added under an ice-cooling condition in order to neutralize the solution. The recovery rates of the citrate added to serum ranged from 92% to 108%, and the coefficient of variation of triplicate assay was 4.2%. The mean serum value of 17 healthy subjects was 1.57 mg/dl, with a range of 1.03-2.03 mg/dl. In seven healthy subjects, 3 g of sodium-potassium citrate was administered orally and the serum citrate was measured 0, 15, 30, 45, 60, and 120 min later. The serum citrate was significantly increased in the periods between 15 and 60 min.

Adult↗

PubMed1991

[Citrate as an inhibitor of stone formation--with reference to intestinal citrate absorption and the influence of citrate on intestinal calcium absorption].

The response of serum citrate to the oral citrate load was studied in seven healthy subjects. Serum citrate was significantly elevated from 15 to 60 min post-load with some individual variations. In 27 stone-formers serum citrate and the response to the oral citrate administration was studied and compared with the results obtained on healthy subjects. The serum citrate concentration of stone-formers was 1.99 +/- 0.49 mg/dl as compared to 1.61 +/- 0.35 mg/dl in healthy subjects. After citrate administration serum citrate increased significantly in both groups, but no significant difference was shown in response to the oral citrate load between these two groups (3.44 +/- 0.94 mg/dl in stone-formers, 3.16 +/- 0.38 mg/dl in healthy subjects). In Sprague-Dawley rats each weighing about 200 g urinary citrate and calcium excretion were studied after administration of sodium citrate or calcium chloride or both. The concomitant equimolar administration of sodium citrate and calcium chloride did not have significant influence on urinary citrate or calcium excretion as compared when citrate or calcium was given alone. However, the calcium excretion was significantly decreased with the administration of citrate and calcium ata molar ratio of 1:2.

Animals↗

PubMed1991

[A case of aortitis syndrome with coronary steal syndrome due to collateral circulation from the right coronary artery to intracranial vessels].

A 44-year old female with aortitis syndrome complained of precordial pain on effort. Exercise electrocardiograms revealed significant ST segment depression in leads II, III, aVF and V. Coronary arteriograms demonstrated no stenosis. However, the right coronary arteriogram revealed collateral circulation arising from the sinus node artery to the bilateral vertebral arteries and the left internal carotid artery. Collateral vessels in aortitis.syndrome arising from the coronary artery to the lung have been reported sporadically. However, to our knowledge, the collateral circulation from the coronary artery to intracranial vessels as seen in the present case has never been reported. In the present case, the left ventricular hypertrophy was observed on electrocardiograms and echocardiograms. It can not be denied that it was a cause of the angina pectoris. However, exercise myocardial scintigraphy showed transient myocardial ischemia at stress on the inferoposterior wall corresponding to leads II, III, aVF and V on electrocardiograms. Therefore, coronary steal syndrome due to the collateral pathway from the coronary artery may be considered a likely cause of the angina pectoris. The collateral circulation was considered to be an important route of blood flow supply to the brain and, at the same time, a cause of coronary steal syndrome and consequently angina pectoris.

Adult↗

PubMed1989

Sulfhydryl groups of an extramitochondrial acetyl-CoA hydrolase from rat liver.

An extramitochondrial acetyl-CoA hydrolase (EC 3.1.2.1) purified from rat liver was inactivated by heavy metal cations (Hg2+, Cu2+, Cd2+ and Zn2+), which are known to be highly reactive with sulfhydryl groups. Their order of potency for enzyme inactivation was Hg2+ greater than Cu2+ greater than Cd2+ greater than Zn2+. This enzyme was also inactivated by various sulfhydryl-blocking reagents such as p-hydroxymercuribenzoate (PHMB), N-ethylmaleimide (NEM), 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB), and iodoacetate (IAA). DL-Dithiothreitol (DTT) reversed the inactivation of this enzyme by DTNB markedly, and that by PHMB slightly, but did not reverse the inactivations by NEM, DTNB and IAA. Benzoyl-CoA (a substrate-like competitive inhibitor) and ATP (an activator) greatly protected acetyl-CoA hydrolase from inactivation by PHMB, NEM, DTNB and IAA. These results suggest that the essential sulfhydryl groups are on or near the substrate binding site and nucleotide binding site. The enzyme contained about four sulfhydryl groups per mol of monomer, as estimated with DTNB. When the enzyme was denatured by 4 M guanidine-HCl, about seven sulfhydryl groups per mol of monomer reacted with DTNB. Two of the four sulfhydryl groups of the subunit of the native enzyme reacted with DTNB first without any significant inactivation of the enzyme, but its subsequent reaction with the other two sulfhydryl groups seemed to be involved in the inactivation process.

Acetyl-CoA Hydrolase↗

PubMed1989

[Basal studies on combination of Chinese medicine in cancer chemotherapy: protective effects on the toxic side effects of CDDP and antitumor effects with CDDP on murine bladder tumor (MBT-2)].

Effects of oral administration of Juzentaihoto, a herb drug, on the toxic side effects of cis-diammine dichloroplatinum (CDDP) and combination effects with CDDP on murine bladder tumor (MBT 2) were studied using C3H/He male mice. The following results were obtained; 1. When the mice were treated with the mixture diet of 1% or 0.5% Juzentaihoto before 2 weeks, adverse effects of high dose CDDP (15 or 17.5 mg/kg) which were included with lethal toxicity, renal and hepatic toxicity, and myelosuppression were protected significantly. The administration of 0.5% Juzentaihoto mixture diet markedly shifted the LD50 to the right. Furthermore, the effects of Juzentaihoto were clearly revealed on the histological findings of testis and kidney. 2. On murine bladder tumor, when the mice were treated with the mixture diet of 1% or 0.5% Juzentaihoto and injected CDDP (2.5 mg/kg/week) for 8 weeks, significantly greater inhibition of the tumor growth and prolongation of the survival rate were observed than those in the group of CDDP alone. These results indicates that Juzentaihoto lessens the toxic side effects of CDDP and that it enhances the effects of CDDP experimentally. Juzentaihoto, a kind of Chinese herb medicine, might come under the category of biological response modifiers.

Administration, Oral↗

PubMed1989

Nephrectomy in situ: treatment of ureteral fistula due to progressive malignancy.

The authors report 2 patients with recurrent retroperitoneal neoplasms in whom ureteral fistulas were treated successfully by percutaneous transcatheter embolization of the renal artery with absolute ethanol. Angio-occlusive nephrectomy is suggested as an alternative to surgical nephrectomy in seriously ill and high-risk patients to preserve their quality of life.

Aged↗