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Biomedical subjects

K Iseki

Publications and source records attributed to K Iseki.

At least 73 records · Page 4Linked to original sources
PubMed1998

[A case of ABO blood group incompatibility treated by exchange transfusion].

A patient with ABO blood group incompatibility who was treated by exchange transfusion is reported. A 63-year-old woman with blood group B type Rh (+) was accidentally transfused approximately 120 ml of A type Rh (+) packed red cells. She developed shock state, complaining chilliness, trepidation, nausea and vomiting just after the atypical blood transfusion. Fortunately, we could save her life without any complication by doing exchange transfusion in addition to anti-shock therapy and anticoagulant therapy preventing disseminated intravascular coagulation. The exchange transfusion was performed while monitoring central venous pressure. The total withdrawn blood reached 4300 ml, and 18 units of B type Rh (+) packed red cells, 10 units of AB type Rh (+) fresh frozen plasmas, 1250 ml of plasma protein fractions and 1750 ml of plasma expanders were infused with crystalloid fluid therapy. Although the amount of atypical blood transfusion to her was relatively small, it is considered that the exchange blood transfusion which seems to be only the fundamental therapy against atypical blood transfusion, took effect in saving her life without any complication.

ABO Blood-Group System↗
PubMed1998

[A female case of Fournier's gangrene in a patient with lupus nephritis].

Infection is one of the common causes of death in patients with systemic lupus erythematosus (SLE). It is associated with the use of immunosuppressive agents, renal failure, and increased disease activity. Fournier's gangrene is a necrotizing fasciitis occurring in the genital region. It is rare, but can be crucial if surgical drainage is delayed. We report a female case of Fournier's gangrene occurring in a patient with lupus nephritis and chronic renal failure. The patient was a 21-year-old female with chronic renal failure due to lupus nephritis. She had suffered from watery diarrhea one month before admission. It improved after increasing the dose of prednisolone, but, she was complicated with Bartholin abscess. The vaginal pain rapidly spread to the left lower quadrant abdomen despite treatment with oral cephalosporin. Focal incision was performed and black fluid emerged with a foul smell. Pelvic computed tomography (CT) revealed many bubbles in that region. She was found to have septic shock on transfer to our hospital. Thereafter, emergency debridement was performed, followed by antibiotic therapy and hyperbaric oxygen therapy. Organisms were found to be 5 anerobes, such as Bacteroides species, and 3 aerobics, such as Morganella morganii. Fournier's gangrene was improved via these treatments, but she needed maintenance hemodialysis. Fournier's gangrene complication should be considered in SLE with urogenital infection.

Adult↗
PubMed1997

Single-step isolation method for six glycoforms of human alpha1-acid glycoprotein by hydroxylapatite chromatography and study of their binding capacities for disopyramide.

A single-step isolation method for the glycoforms of human serum alpha1-acid glycoprotein (AAG) using a hydroxylapatite column under a gradient elution program was developed. The concentrations of N-acetylneuraminic acid and monosaccharides (fucose, N-acetylglucosamine, galactose and mannose) of six AAG glycoforms were determined by the pulsedamperometric detection method. For each AAG glycoform, significant sex-related differences in carbohydrate content have been observed only for AAG glycoforms two and six, and not for each AAG glycoform. The relationship between the extent of the branch in the glycan chain and the binding capacity to disopyramide were examined. Female AAG contained highly sialylated AAG glycoforms compared to male glycoforms. Conversely, male AAG was rich in the lower sialylated AAG glycoform. Furthermore, it was found that the drug binding capacity decreases with increasing branching of the glycan chain. This suggests that the binding sites of AAG are hindered by a relatively large carbohydrate moiety, such as tetraantennary structures.

Adult↗
PubMed1997

Reduction in NaCl-enhanced gastric carcinogenesis in rats fed a high-protein diet.

The effect of a purified, high protein diet on enhanced gastric carcinogenesis induced by oral administration of NaCl was investigated in Wistar rats. Rats were fed on a purified diet with an equalized caloric content, containing 8% NaCl and 25% casein (normal protein diet), or 50% casein (high protein diet) after oral treatment with N-methyl-N'-nitro-N-nitrosoguanidine for 25 weeks. In week 52, oral administration of NaCl had significantly increased the incidence and size of gastric cancer in rats fed a normal protein diet. However, NaCl had no significant effect on gastric carcinogenesis in rats fed a high protein diet. Oral administration of NaCl also caused a significant increase in tissue norepinephrine concentrations in the antral portion of the gastric wall, and increased the labeling indices of the antral epithelial cells of rats fed on a normal protein diet. However, in rats fed a high protein diet, administration of NaCl had no significant influence on these two parameters. These findings indicate that a high protein diet attenuates enhanced gastric carcinogenesis induced by the administration of NaCl, and that this effect may be related to its ability to decrease norepinephrine concentrations in the gastric wall, which subsequently decreases the proliferation of antral epithelial cells.

Animals↗
PubMed1997

Enhancement by ethyl alcohol of experimental hepatocarcinogenesis induced by N-nitrosomorpholine.

The effects of ethyl alcohol (EtOH) during or after treatment with N-nitrosomorpholine (NNM) on hepatocarcinogenesis, ornithine decarboxylase (ODC) activity and the labeling index of the liver were investigated in male Sprague-Dawley rats. Rats were given drinking water containing NNM for 8 weeks and received i.p. injections of 1 g EtOH/kg body weight every other day during or after treatment with NNM. Pre-neoplastic and neoplastic lesions staining positively for glutathione-S-transferase, placental type (GST-P), were examined immunohistochemically. At the end of experiment at week 16, administration of EtOH after NNM treatment had no significant effect on the number and size of GST-P-positive hepatic lesions, whereas administration of EtOH during NNM treatment significantly increased the number and percentage area but not the mean area of GST-P-positive hepatic lesions. EtOH caused significant increases in the ODC activity of the liver and in the labeling indices of enzyme-altered lesions and the adjacent hepatocytes after the cessation of EtOH administration but not during EtOH treatment. Our findings indicate that EtOH enhances hepatocarcinogenesis and suggest that this effect may be closely related to the increases in ODC activity and cell proliferation in enzyme-altered lesions and the adjacent liver after EtOH treatment.

Animals↗
PubMed1997

Enhancement by monochloramine of the development of gastric cancers in rats: a possible mechanism of Helicobacter pylori-associated gastric carcinogenesis.

The effects of cytotoxic monochloramine on the development of gastric cancers induced by N-methyl-N'-nitro-N-nitrosoguanidine were investigated in Wistar rats. After oral administration of drinking water containing the carcinogen and regular chow pellets for 25 weeks, rats received regular chow pellets or chow pellets containing 20% ammonium acetate, and normal tap water or water containing 30 mM sodium hypochlorite, with or without s.c. injection of taurine, until the end of the experiment in week 52. Treatment with both ammonium acetate and sodium hypochlorite significantly increased the incidence of gastric cancers in week 52, while the concomitant use of taurine with ammonium acetate and sodium hypochlorite significantly attenuated the enhanced gastric carcinogenesis. Spectrophotometric examinations revealed that taurine scavenged monochloramine. These findings suggest that Helicobacter pylori-associated gastric carcinogenesis may be mediated by monochloramine.

Animals↗
PubMed1997

Risk factors of end-stage renal disease and serum creatinine in a community-based mass screening.

This study evaluated risk factors for end-stage renal disease (ESRD) and the prognostic significance of serum creatinine levels in a community-based mass screening. We used the registries of both community-based mass screening and chronic dialysis programs. In 1983, a total of 107,192 subjects over 18 years of age (51,122 men and 56,070 women) participated in a mass-screening program in Okinawa, Japan. Among them, serum creatinine data were available for 14,609 participants (5,613 men and 8,996 women). During 10 years of follow-up, we identified 60 dialysis patients (29 men and 31 women) among this group. Logistic regression analysis on the risk of ESRD was performed to determine the significance of serum creatinine levels in comparison with other clinical variables. The adjusted odds ratio (95% confidence interval) was 5.31 (3.39 to 8.32) in men and 3.92 (2.88 to 5.34) in women when compared to baseline serum creatinine levels of less than 1.0 mg/dl in women and 1.2 mg/dl in men. Diastolic blood pressure was not a significant predictor of ESRD. Results demonstrated the prognostic significance of serum creatinine in a community-based mass screening. Gender difference in the incidence of ESRD was explained, at least partly, by differences between clinical predictors and baseline serum creatinine levels.

Adolescent↗
PubMed1997

Low diastolic blood pressure, hypoalbuminemia, and risk of death in a cohort of chronic hemodialysis patients.

In a previous report, we showed that nutritional status and especially serum albumin had great predictive value for death in chronic hemodialysis patients, whereas blood pressure did not. In the present study, we analyzed the causes of death in consideration of the relationship between serum albumin and blood pressure. A total of 1,243 Okinawan patients (719 males, 524 females) undergoing hemodialysis in January 1991 were followed up through the end of 1995. Three hundred forty-two of the patients died, 45 received transplants, and 12 were transferred by the end of the follow-up period. The total duration of observation was 5,110.3 patient-years. Blood pressure as well as clinical and laboratory variables were determined immediately prior to the first dialysis session in January 1991. The crude death rate was 40.0% when the diastolic blood pressure (DBP) <70 mm Hg, 35.0% at 70 to 79 mm Hg, 25.0% at 80 to 89 mm Hg, 25.0% at 90 to 99 mm Hg, and 13.0% at >100 mm Hg. The death rate showed an inverse correlation with DBP. DBP showed a significant positive correlation with serum albumin (r = 0.137, P < 0.001) and age (r = -0.325, P < 0.0001). The adjusted odds ratio (95% confidence interval) of death was 0.84 (0.71 to 0.99) with 10 mm Hg increments in DBP when the reference DBP was less than 69 mm Hg. Low DBP may be a manifestation of malnutrition and/or cardiovascular disease in chronic hemodialysis patients. Target DBP levels may be higher levels in chronic hemodialysis patients than the general population.

Blood Pressure↗
PubMed1997

The mechanism of excretion of trientine from the rat kidney: trientine is not recognized by the H+/organic cation transporter.

Trientine dihydrochloride is used to treat Wilson's disease by chelating copper and increasing its urinary excretion. The mechanism of renal excretion of trientine has been investigated in-vivo and in-vitro. Trientine clearance in the rat-was significantly faster than creatinine clearance. When trientine and the same number of moles of copper ions were administered simultaneously to the rat, however, trientine clearance decreased to almost the same level as the creatinine clearance. To clarify this active excretion system for trientine, the uptake of trientine and a physiological polyamine compound, spermine, was investigated using rat renal brush-border membrane vesicles. Although, because trientine and spermine are organic cations, the H+/organic cation transporter is expected to recognize these compounds, neither an outwardly directed H+ gradient nor an inward Na+ gradient stimulated trientine uptake. [14C]Spermine uptake was, nevertheless, trans-stimulated by both unlabelled spermine and trientine and the trans-stimulating effect of spermine on trientine uptake was, furthermore, completely abolished by addition of copper ions to the incubation medium. These results suggest that there is a specific transport system for spermine and trientine on the renal brushborder membrane. This transport system contributes to the secretion of trientine in the kidney proximal tubule but does not recognize the trientine-copper complex.

Animals↗
PubMed1997

A structure-relationship study of the uptake of aliphatic polyamine compounds by rat intestinal brush-border membrane vesicles.

The effects of lipophilicity, ion-diffusion potential and membrane surface potential on the uptake of various aliphatic polyamine compounds by rat intestinal brush-border membrane vesicles (BBMV) have been investigated. A valinomycin-induced potassium-diffusion potential (inside-negative) stimulated the initial uptake of diamine compounds, and good correlation was observed between lipophilicity and the amount of diffusion-potential-dependent transport of the diamines. In contrast, because of their much lower lipophilicity, tri- and tetraamine compounds were not affected by the diffusion potential. Tetracaine, which can make the membrane surface potential more positive, inhibited the transport rate of 1,9-nonanediamine, spermidine and spermine by the BBMV. These data suggest that the transport mechanism of diamines is similar to that of monoamine compounds in respect to its dependence on ion-diffusion potential and on the membrane surface potential. The extent of the effect of ion-diffusion potential on the rate of transport of the diamines was closely related to the lipophilicity of the diamine. In contrast, only the surface potential contributed to the transport mechanism of lower lipophilic tri- and tetraamine compounds.

Anesthetics, Local↗
PubMed1997

The effect of membrane surface potential on the permeability of anionic compounds across the apical membrane in human intestinal epithelial (Caco-2) cells.

The effect of membrane surface potential of the apical side on the intracellular uptake of ionic compounds was investigated using the human colon adenocarcinoma cell line (Caco-2). The transepithelial transport of indolepropionic acid and tryptamine was consistent with the uptake behavior shown by rat intestinal brush-border membrane (BBM) vesicles. Imipramine, which diminished the negative charge of the membrane surface (for both Caco-2 and BBM), acted to increase the uptake of the anionic compounds, indolepropionic acid and ceftibuten, and to decrease that of tryptamine (cationic compound) by both the Caco-2 monolayer and the intestinal BBM vesicles at a pH of 7.5. These results suggest that the effects of membrane surface potential on the permeability of ionic compounds were detectable on the Caco-2 cell line as well as the BBM vesicles. On the other hand, the inhibition of H(+)-linked transport and the stimulation of the surface charge-regulated uptake of ceftibuten have occurred simultaneously on the Caco-2 cell line in the presence of imipramine. It seems that the membrane surface charge (negative) plays an important role in the transport process of ionic compounds across the intestinal epithelium.

Adenosine Triphosphate↗
PubMed1997

[Content determination of baicalin and baicalein in shuanghuanglian powdery injection by the method of HPLC-ECD].

The contents of baicalin and baicalein in Shuanghuanglian Powdery Injection have been determined by the method of HPLC-ECD under following conditions: column-ERC-ODS-1161, 6 mm x 100 mm; temperature-55 degrees C; mobile phase-0.1 mol/L KH2PO4, acetic acid and tetrahydrofuran (1000:100:190); flow rate-0.8 ml/min; detector voltage-+650 mV. The result shows the limit of detection for baicalin and baicalein to be 25 ng and 50 ng respectively, with an average recovery of 100.1% and 99.7% respectively. Highly reproducible, rapid, simple, convenient and accurate, this method is good for the content determination of baicalin and baicalein in Chinese medicinal herbs and preparations.

Chromatography, High Pressure Liquid↗
PubMed1997

Predictors of end-stage renal disease and body mass index in a screened cohort.

The effect of body mass index (BMI) on the risk of developing end-stage renal disease (ESRD) has not been critically evaluated. To investigate this issue we used the registries of community-based mass screening and chronic dialysis programs. In 1983, a total of 101,516 subjects (47,901 men and 53,615 women) participated in a mass screening program in Okinawa, Japan. A total of 187 (101 men and 86 women) entered an ESRD program by March 31, 1994. Body mass index was calculated as weight in kilograms divided by the square of the height in meters. Subjects were categorized into six groups based on BMI: < 20.0, 20.0-21.9, 22.0-23.9, 24.0-25.9, 26.0-27.9, and > or = 28.0 kg/m2. The cumulative incidence of ESRD, per 100,000 subjects was calculated in each BMI subgroup for men and women. In men, the cumulative incidence of ESRD increased with BMI, except in the range of 24.0 to 25.9 kg/m2. In women, the association between the cumulative incidence of ESRD and BMI was not clear, but was lowest in the range of 24.0 to 25.9 kg/m2. The adjusted odds ratio (95% confidence interval) was 0.99 (0.92 to 1.13) in men and 0.83 (0.72 to 0.96) in women.

Adult↗
PubMed1996

Inhibition by the calmodulin antagonist trifluoperazine of experimental hepatocarcinogenesis induced by N-nitrosomorpholine in Sprague-Dawley rats.

The effect of the calmodulin antagonist trifluoperazine on hepatocarcinogenesis induced by N-nitrosomorpholine (NNM) and on the ornithine decarboxylase (ODC) activity and labeling index of the liver were investigated in male Sprague-Dawley rats. Rats were given drinking water containing NNM for 8 weeks, and from the beginning of the experiment, received s.c. injections of 15 or 30 mg/kg body weight of trifluoperazine in depot form every other day until the end of the experiment. Preneoplastic and neoplastic lesions staining positively for glutathione-S-transferase, placental type (GST-P) were examined histochemically. In week 16, quantitative histological analysis showed that prolonged administration of 30 mg but not 15 mg/kg body weight of trifluoperazine resulted in significant reductions in the number and percentage area of GST-P-positive hepatic lesions. Trifluoperazine also caused significant decreases in the ODC activity of the liver and in the labeling indices of enzyme-altered lesions and their adjacent hepatocytes. These findings indicate that trifluoperazine inhibits carcinogenesis and suggest that this effect may be closely related to its effect in inhibiting ODC activity and cell proliferation in the enzyme-altered lesions and their adjacent liver.

Animals↗
PubMed1996

Solubilization and reconstitution characteristics of the carrier protein(s) responsible for the transport of ceftibuten, a substrate for the oligopeptide transporters, in rat renal brush-border membrane.

Optimal procedures for the reconstitution of the transport activity of ceftibuten, a dianionic beta-lactam antibiotic, from rat kidney brush-border membrane were developed. The uptake activity into reconstituted proteoliposomes appeared to be particularly sensitive to the extraction conditions, and to the lipid composition used for reconstitution. Changes in the concentration of octyl glucoside significantly affected the extraction of ceftibuten transport activity, and optimal extraction was achieved at a concentration of 60 mM. Optimal reconstitution was achieved using a lipid composition of asolectin, cholesterol and phosphatidylserine in a w/w percent ratio of 60:30:10, respectively, and with a lipid-to-protein ratio of 10. The uptake of ceftibuten into the resulting proteoliposomes showed temperature and pH dependency, was inhibitable by a range of cephem antibiotics, oligopeptides and the organic anion PAH, and was trans-stimulated by cephalexin and dipeptides. This reconstitution system will likely prove useful in future studies on the functional analysis of the peptide transport system in a purified form.

Animals↗
PubMed1996

Inhibition by amiloride of experimental carcinogenesis induced by azaserine in rat pancreas.

The effects of prolonged administration of the diuretic amiloride on pancreatic carcinogenesis induced by azaserine and on the labeling index of carcinogen-induced pancreatic lesions were investigated in Wistar rats. Rats were given 25 weekly injections of 10 mg/kg body weight azaserine and also 5 mg/kg body weight amiloride every other day until the end of the experiment at week 62. Carcinogen-induced pancreatic lesions were examined by histochemical techniques and were classified as ATPase-positive or ATPase-negative. In week 62, quantitative histologic analysis showed that prolonged administration of amiloride significantly reduced the number and size (as percent of parenchyma) of ATPase-positive pancreatic lesions, which are closely correlated with the subsequent development of pancreatic cancer. Amiloride also significantly decreased the labeling index of carcinogen-induced pancreatic lesions, but not of the surrounding acinar cells. In contrast, amiloride has no significant influence on the number and size of ATPase-negative pancreatic lesions. These findings indicate that amiloride inhibits pancreatic carcinogenesis, and that this effect may be related to the reduction of ATPase-positive lesions and to amiloride's inhibition of cell proliferation in neoplastic lesions of the pancreas.

Adenosine Triphosphatases↗
PubMed1996

Transport mechanisms of nucleosides and the derivative, 6-mercaptopurine riboside across rate intestinal brush-border membranes.

Na+ -driven nucleoside transport processes across rat intestinal brush-border membrane vesicles were investigated. 6-Mercaptopurine riboside (6-MPR), an analogue of purine-nucleoside such as adenosine and inosine, was recognized by its purine- and pyrimidine-nucleosides transport system, but their nucleobases did not entirely inhibit the 6-MPR transport. The analysis according to the Hill equation of the curve of Na+ activation of 6-MPR uptake was consistent with the notion of a Na+/6-MPR coupling stoichiometry of 1:1. The expressed transport activities of adenosine, uridine, and 6-MPR were Na+ -dependent and saturable, and their affinity constants (Km value) obtained by Eadie-Hofstee analysis were approx. 20, 15 and 100 microM. Moreover, the uptake of radiolabeled adenosine and uridine was trans-stimulated by 6-MPR inside vesicles in the absence of an inwardly directed Na+ gradient. On the other hand, uridine did not exhibit any inhibitory effects on the uptake of adenosine despite the fact that adenosine was a potent inhibitor of uridine uptake by intestinal brush-border membrane vesicles. These differences in the inhibition may be explained by the multiplicity of the nucleoside transport systems.

Adenosine↗