Biomedical subjects

Y Kanno

Publications and source records attributed to Y Kanno.

At least 91 records · Page 5Linked to original sources

PubMed1995

Renal effects of amlodipine.

The effects of a new dihydropyridine calcium channel blocker, amlodipine, on blood pressure (BP) and renal function were studied in spontaneously hypertensive rats (SHR). These effects were compared with those of an angiotensin-converting enzyme (ACE) inhibitor, enalapril. In addition, the effects of amlodipine on BP and renal function were studied in hypertensive patients with renal impairment. In five of six nephrectomised salt-loaded SHR, increases in BP, urinary excretion of protein and serum creatinine were attenuated by the administration of 2 mg/kg/day of amlodipine. The progression of renal histological damage was also markedly decreased. The protective effects of amlodipine against renal damage were similar to those of enalapril. However, the mechanisms of action of these two agents seem to differ as, unlike enalapril, amlodipine did not significantly dilate the efferent arteriole in hydronephrotic perfused rat kidney. In a clinical study, 2.5-5 mg/day of amlodipine was administered once a day for 8-10 weeks to 39 hypertensive patients with renal impairment (serum creatinine > or = 1.5 mg/dl to < 5 mg/dl) or renal parenchymal disease (serum creatinine < 5 mg/dl). A significant reduction in BP (reduction of mean BP > or = 13 mm Hg) was observed in 28 patients (80%). Headache was experienced as a side-effect in one of 35 patients (2.9%). With respect to the influence of amlodipine on renal function, mean values of blood urea nitrogen and serum creatinine were unchanged for the total group whereas a slight elevation of serum creatinine was observed in four of 35 patients (11.4%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

The mouse Rxrb gene encoding RXR beta: genomic organization and two mRNA isoforms generated by alternative splicing of transcripts initiated from CpG island promoters.

Two major isoforms of retinoid X receptor beta (RXR beta; H-2RIIBP), encoded by the Rxrb gene, have been identified in the mouse. Northern analysis of Rxrb mRNA showed two close bands of 2.8 and 2.6 kb in many tissues and cell lines. They are designated as mRxr beta 1 and mRxr beta 2, respectively. Some rapidly growing cell lines and spleen tissue had about twofold more Rxr beta 1 mRNA than Rxr beta 2 whereas most adult tissues had similar amounts of both beta 1 and beta 2. Amino acid (aa) sequences deduced from cDNAs show an extra N-terminal domain of 72 aa for RXR beta 1 that is well conserved between mouse and human, but not found in RXR beta 2. These isoforms are generated from separate exons transcribed from different CpG island promoters and spliced into the common acceptor site in the transactivation domain by an alternative splicing. The Rxrb gene contains an intron in the midst of the first zinc-finger coding region. This is different from the retinoic acid receptor (RAR) and other nuclear receptor superfamily genes that contain an intron between the first and the second zinc-finger coding regions. These results, together with their unique ability to form heterodimers with other members of the superfamily, suggest a distinct phylogenic position for the Rxr genes.

Alternative Splicing↗

PubMed1994

Coculture of mouse embryos with cryopreserved human oviduct epithelial cells.

PURPOSE: The effect of coculturing mouse embryos with cryopreserved human oviduct epithelial cells was investigated. The cryopreserved cells in Cellbanker were thawed and cultured in Richard D. Goldsby culture medium to establish monolayers. Two-cell-stage mouse embryos were cultured alone (control group) or cocultured with monolayers established from cryopreserved cells (cryopreserved coculture group) or from fresh cells (fresh coculture group). The rates of embryo development and the qualities of the blastocysts in the three groups were compared. RESULTS: The two coculture groups had significantly higher blastocyst development rates (cryopreserved coculture group, 81.6%; fresh coculture group, 82.2%) than the control group (63.1%). The two coculture groups had significantly more blastomeres (cryopreserved coculture group, 108.3 +/- 25.9; fresh coculture group, 108.4 +/- 25.1) than the control group (87.7 +/- 31.9). CONCLUSION: The method of cryopreservation of human oviduct epithelial cells using Cellbanker is simpler than conventional cryopreservation methods. These cryopreserved human oviduct epithelial cells may provide a constant supply of cells for coculture for in vitro fertilization and embryo transfer.

Adult↗

PubMed1994

Interleukin-4 expression in mesangial proliferative glomerulonephritis.

Several cytokines are known to play roles in the pathogenesis of human glomerulonephritis. Recently, some studies proposed a possible relationship between interleukin-4 (IL-4) and glomerulonephritis. To investigate the involvement of IL-4 in human glomerulonephritis, we evaluated renal biopsy specimens using immunohistochemical procedures. Our study revealed that the glomeruli in immunoglobulin A nephropathy and lupus nephritis (World Health Organization grades II and IV) contained IL-4-positive cells, which were CD-3- and CD-4-positive T lymphocytes. CD-8-, CD-14-, CD-19-, or CD-56-positive cells did not react with anti-IL-4. CD-23-positive cells were not observed in the sections used in this study. Interleukin-4-positive cells were not found in the normal control kidney tissues. The degree of the glomerular IL-4-positive cell index correlated well with the glomerular hypercellularity index, but not with any other clinical or histopathologic parameters. Therefore, the present study offers more reliable evidence concerning the association between IL-4 and human glomerulonephritis.

Adult↗

PubMed1994

Effects of vasopressin V1 and V2 receptor antagonists on progressive renal failure in rats.

1. The relationship between vasopressin and the progression of renal failure has been proposed, but not intensively investigated because of a lack of orally available, selective vasopressin antagonists. 2. The effects of novel, orally available vasopressin V1 and V2 receptor antagonists on several indices of the progression of chronic renal failure, i.e. blood pressure, urinary protein excretion, sodium balance and renal histopathology, were investigated by using Wistar rats with adriamycin-induced nephropathy accelerated by deoxycorticosterone acetate-salt hypertension. Groups 2 and 3 were treated with V1 and V2 antagonists, respectively, while the untreated group 1 served as the control. To block the effects of vasopressin efficaciously, V1 and V2 antagonists were simultaneously administered (group 4). 3. At week 6, 2 weeks after the beginning of administration of deoxycorticosterone acetate-salt and vasopressin antagonists after the second injection of adriamycin, V1 and V2 antagonists given either alone or in combination significantly reduced the systolic blood pressure as compared with the control, and urine volume was increased in groups 3 and 4. The proteinuria was also decreased at week 10 in groups 2, 3 and 4. Differences in sodium excretion between all groups were not significant. Histopathological alterations in the kidneys of group 4 were significantly ameliorated. 4. These results suggest that a combination of V1 and V2 antagonists can have therapeutic effects in certain types of chronic renal failure.

Animals↗

PubMed1994

Quantification of erythema and pigmentation using a videomicroscope and a computer.

We report a method for quantitative analysis of erythema and pigmentation using a videomicroscope interfaced with a computer. The analysis was carried out by examining the brightness intensity of every picture element, composed of an image picked up from each band of red, green, and blue, and by deriving the quasi-absorbance value (absorbance index) from the mean brightness for each band. In assessments of UV-induced erythema and tanning, excellent linear correlations were found between the results obtained with our system and those with a narrow-band reflectance spectrometer. Moreover, the absorbance indices of haemoglobin and melanin solutions showed linear relationships with their concentrations in in vitro examination. As the monitored picture becomes out of focus if incorrect pressure is exerted on the skin, and as regions of interest can be chosen from a magnified image, this system offers excellent interobserver reproducibility, and is suitable for the evaluation of erythema or pigmented lesions which are too small or irregular to quantify by conventional methods such as colorimetry.

Adrenal Cortex Hormones↗

PubMed1994

Chronic and selective vasopressin blockade in spontaneously hypertensive rats.

Chronic effects of orally available, nonpeptide vasopressin V1 and V2 receptor antagonists on conscious spontaneously hypertensive rats (SHR) were investigated. SHR and Wistar rats were divided into four groups, groups S-1 to S-4 and W-1 to W-4, respectively. Groups S-1 and W-1 were untreated as control. Groups S-2 and W-2 were treated with V1 antagonist, groups S-3 and W-3 received V2 antagonist, and groups S-4 and W-4 were treated with both of V1 and V2 antagonists. V1 and/or V2 antagonists did not affect degree of blood pressure of W-2, W-3, and W-4 rats, and V1 antagonist, alone or combined with V2 antagonist, slightly reduced increases in blood pressure of S-2 and S-4 rats without significance. However, V2 antagonist induced significantly massive and hyposmolar urine in W-3 rats compared with that in S-3 rats. In conclusion, in SHR, circulating vasopressin contributes to increases in blood pressure via either V1 or V2 receptors less than expected from previous studies with antibodies or peptide antagonists.

Animals↗

PubMed1994

Metabolic coupling of glutathione between mouse and quail cardiac myocytes and its protective role against oxidative stress.

Cultured quail myocytes were much more resistant to H2O2 toxicity than cultured mouse myocytes. The intracellular concentration of glutathione ([GSH]i) and the activity of gamma-glutamylcysteine synthetase (gamma-GCS) in quail heart cells were about five and three times higher, respectively, than in mouse heart cells, although catalase and glutathione peroxidase (GSHpx) activity was similar in both. Preloading of gamma-glutamylcysteine monoethyl ester (gamma-GCE), a membrane-permeating GSH precursor, increased the H2O2 resistance of cultured mouse myocytes. These observations suggest that the high [GSH]i and the high activity of gamma-GCS in quail myocytes are responsible for their high resistance to H2O2. Both H2O2 sensitivity and [GSH]i of mosaic sheets composed of equal amounts of mouse and quail myocytes approximated those of sheets composed entirely of quail myocytes. From these observations, it is hypothesized that GSH was transferred from quail myocytes to mouse myocytes, probably through gap junctions between them, and that quail myocytes resynthesized GSH by a feedback mechanism, thus maintaining their intracellular GSH levels. When the fluorescent dye lucifer yellow was injected into a beating quail myocyte in a mosaic sheet, it spread to neighboring mouse myocytes but not to neighboring L cells (a cell line derived from mouse connective tissue). These observations indicate that existence of gap junctions in the region of cell contact between mouse and quail myocytes but not between quail myocytes and L cells. When quail myocytes preloaded with [3H]gamma-GCE were cocultured with mouse myocytes and L cells, the radioactivity was transmitted to neighboring mouse myocytes but not L cells. These observations show that GSH and/or its precursors can be transmitted from quail myocytes to mouse myocytes through gap junctions and that this can protect mouse myocytes from H2O2 toxicity. Mouse myocyte sheets composed of 10(4) cells or more showed higher resistance to H2O2 toxicity than single isolated mouse myocytes. Metabolic coupling of GSH between myocytes may contribute at least in part to this high resistance of the cell sheets.

Animals↗

PubMed1994

Acquired idiopathic pure red cell aplasia in a hemodialyzed patient with inactive systemic lupus erythematosus.

A male patient suffered chronic renal failure due to lupus nephritis and was undergoing hemodialysis. Six years after beginning hemodialysis, anemia developed, which improved by erythropoietin. Unresponsiveness to erythropoietin gradually appeared, and with a suspicion of pure red cell aplasia, he was treated with a high-dose corticosteroid but the unresponsiveness did not improve. Neither his serum nor lymphocytes inhibited erythropoiesis of either normal bone marrow stem cells or his own in vitro. These observations suggest an impaired hematopoietic microenvironment in his bone marrow.

Adrenal Cortex Hormones↗

PubMed1994

Renal protective effects of amlodipine on partially nephrectomized spontaneously hypertensive rats fed a high-salt diet.

We examined the effects of a calcium-channel blocker amlodipine on progression of renal failure in 5 of 6 nephrectomized spontaneously hypertensive rats (SHR) fed a high-salt diet. Twelve SHR, 5 of 6 with nephrectomy and salt-loading, were divided into two group: group 1 as control (n = 6) and group 2 treated with 2 mg/kg/day amlodipine (n = 6). During the 10 study weeks, body weight, systolic blood pressure (SBP), and daily urinary protein excretion were measured every 2 weeks. At the end of the study, serum creatinine, urea nitrogen, and total protein and albumin were determined. Renal tissues were obtained for light microscopic examination. The increase in SBP after 10 study weeks was significantly less in the treated group than in the control group (control 287 +/- 5 mm Hg; amlodipine 237 +/- 23 mm Hg (p < 0.01)). Urinary protein excretion was also suppressed in the amlodipine-treated group (p < 0.01). Although in the control group glomerular sclerosis and hyalinosis were marked, they were significantly less in the amlodipine-treated group. These results illustrate that amlodipine can attenuate BP increase and inhibit progression of hypertensive renal injury in this rat model.

Amlodipine↗

PubMed1994

Nonpeptide angiotensin II type 1 receptor antagonist prevents nephrosclerosis in hypertensive rats.

Angiotensin II (AII) appears essential in remnant kidney models of renal injury in rats, and renal injury was reduced by angiotensin-converting enzyme inhibitor (ACEI). To determine whether this is due to AII blockade or other actions of ACEI, we studied a nonpeptide AII type 1 receptor antagonist and an ACEI in partially nephrectomised spontaneously hypertensive rats (SHR). Thirty SHR underwent surgery and were divided into three equal groups: Control, TCV (0.5 mg/kg/day TCV-116), and CAP (30 mg/kg/day captopril). All SHR received a 5%-NaCl diet. Systolic blood pressure (SBP) and urinary protein were measured at 2-week intervals. Serum total protein, albumin, urea nitrogen, and creatinine were determined at week 8. Glomerular filtration rate (GFR) and renal blood flow (RBF) were measured at weeks 4 and 8. Renal injury was evaluated histopathologically. TCV and CAP reduced SBP at week 2 and proteinuria at week 8. GFR and RBF fell in all groups, but decreases were not significant in treated SHR and histopathological changes were significantly ameliorated. All blockade by TCV or CAP reduces renal injury in salt-loaded SHR with partial renal ablation. AII is essential in remnant kidney models of renal injury, and AII blockade is essential in renal protection by ACEI.

Angiotensin Receptor Antagonists↗

PubMed1993

The genomic structure of the murine ICSBP gene reveals the presence of the gamma interferon-responsive element, to which an ISGF3 alpha subunit (or similar) molecule binds.

ICSBP, a member of the interferon regulatory factor family, is expressed predominantly in lymphoid tissues and is induced by gamma interferon (IFN-gamma). We have studied the genomic organization of the murine ICSBP gene and its 5' upstream region. The murine ICSBP gene (Icsbp) is present as a single copy on chromosome 8 and consists of nine exons. Transcription initiates at two juxtaposed sites downstream from the TATA and CAAT boxes and produces two species of ICSBP mRNA (3.0 and 1.7 kb), presumably by differential usage of poly(A)+ signals. A sequence from -175 to -155 was identified to be an IFN response region that conferred IFN-gamma induction upon a heterologous promoter in lymphoid cell line EL4. This region includes a motif, TTCNNGGAA, designated the palindromic IFN response element (pIRE), to which an IFN-gamma-inducible, cycloheximide-sensitive factor(s) binds. A similar palindromic motif was found in the upstream region of the murine IRF-1 gene, the IFN-gamma activation site of the guanylate-binding protein gene and the IFN-gamma-responsive region of the Fc receptor type I gene, all of which competed with the pIRE for factor binding in gel mobility shift assays. We show that the pIRE binding factor reacts with the antibody against the 91-kDa subunit of ISGF3 alpha recently shown to bind to the IFN-gamma activation site. These results suggest that this factor is related to the IFN-gamma activation factor and contains the 91-kDa subunit of ISGF3 alpha. Taken together, pIRE represents an IRE that is distinct from the classical IFN-stimulated response element and that is capable of conferring IFN-gamma induction through the binding of the 91-kDa ISGF3 alpha subunit (or an antigenically similar molecule).

Animals↗

PubMed1992

Differences in myocardial fluoro-18 2-deoxyglucose uptake in young versus older patients with hypertrophic cardiomyopathy.

The purpose of this study was to determine whether regional myocardial glucose use in patients diagnosed as having hypertrophic cardiomyopathy (HC) at a younger age differs from that in those diagnosed at middle to old age. Sixteen patients with HC (group 1 aged less than 40 years (n = 8); group 2 aged greater than 40 (n = 8) were studied using positron emission tomography and fluoro-18 2-deoxyglucose (FDG). All patients were diagnosed as having HC within 6 years of the study. Contiguous regions of interest were selected circumferentially on each cross-sectional image of the left ventricular wall. In each region of interest, % FDG fractional uptake was calculated. In each patient, % left ventricular FDG fractional uptake was determined as a mean value of % FDG fractional uptake in each region of interest. Moreover, as a measure of nonhomogeneity, the % interregional coefficient of variation in FDG fractional uptake was calculated in each patient. Whereas % left ventricular FDG fractional uptake did not differ between the 2 groups, the % interregional coefficient of variation in FDG fractional uptake was increased in group 1 compared with that in group 2 (11.5 +/- 3.6 vs 7.4 +/- 1.6%; p less than 0.02). Interventricular septum/left ventricular posterior wall thickness ratio and total counts in cross-sectional image did not differ between the 2 groups. These data suggest that patients diagnosed as having HC at a younger age have more nonhomogeneous myocardial metabolic characteristics than do patients diagnosed at middle or old age, and support the notion that HC in the young may be different from that in the middle-aged or elderly.

Adolescent↗

PubMed1992

Tsutsugamushi disease in the central part of Japan.

Two cases of tsutsugamushi disease misdiagnosed initially as drug eruption were reported. Clinical symptoms of both cases disappeared dramatically after starting minocycline. Statistical examinations were performed on 29 cases of tsutsugamushi disease, including those observed in Mie Prefecture since 1982. Half of them were seen in the last 2 years. The onset was predominantly recorded in November (59%). Presumptive sites of infection were forests (63%) and fields (21%). No patients were infected along river-banks.

Adult↗

PubMed1992

Tsutsugamushi disease (scrub typhus).

Two patients with Tsutsugamushi disease (fever) were successfully treated with tetracycline derivatives after typical eschars were found, although one of the patients was initially misdiagnosed as having a drug reaction eruption. Prompt diagnosis and treatment are important because this disease can be associated with considerable morbidity and simple effective treatment is easily available.

Adult↗

PubMed1992

Three-lineage hemopoietic precursor cells and effectiveness of recombinant human erythropoietin in patients with myelodysplastic syndromes.

Four-stem-cell assays, which evaluate megakaryocytic (CFU-Meg), immature and mature erythropoietic (BFU-E, CFU-E), and granulocyte-macrophage (CFU-GM) colony formation, were performed in nine patients with myelodysplastic syndromes (MDS). The CFU-Meg, BFU-E, and CFU-E colony growths were disturbed more often than the CFU-GM colony formation. A CFU-E increase was not recognized in most MDS patients, but a dose-dependent increase of bone marrow CFU-Es in response to erythropoietin (EPO) was recognized only in two refractory anemia (RA) patients whose CFU-Es were more than one tenth of normal controls. One patient with RA and the other with chronic myelomonocytic leukemia (CMML), both of whose bone marrow CFU-Es did not increase at the higher dose of EPO in vitro, were treated with recombinant human EPO (rHuEPO), resulting in no effects. The responsiveness of patients with MDS to various recombinant hemopoietic factors might be predicted by both the residual degree of bone marrow hematopoietic precursor cells and the response of stem cells to the higher doses of each hemopoietic factor.

Adult↗

PubMed1992

[Renal and electrolyte disturbances in chronic myelogenous leukemia].

Renal and electrolyte disturbances in 91 patients with chronic myelogenous leukemia (CML) were analyzed over a period of these twenty years. At diagnosis, renal and electrolytes were studied in 72 patients including 65 in chronic cases, 5 in accelerated phase and 2 in blastic crisis. There were 8 cases of hypocalcemia among 62 patients and 5 cases of hyperphosphatemia among 48 patients. The cases of hyperphosphatemia and renal dysfunction had short median survival. There were no significant differences of renal and electrolyte disturbances between before and after chemotherapy. Various electrolyte disturbances, that is, hyponatremia, hypo-, hyperkalemia, hypocalcemia, hypo-, hyperphosphatemia, were found in the blastic crisis of CML. In the last admission, renal dysfunction and various electrolyte disturbances were present in almost half of the cases. Pathological studies were performed in 18 autopsy cases. Acute tubular insufficiency or necrosis, hypercalcemic nephropathy, and renal infiltration of leukemic cells were recognized in patients who had renal dysfunction.

Adolescent↗

PubMed1992

Hepatitis virus infection (HBV and HCV) in eleven Japanese hemodialysis units.

To evaluate hepatitis C virus (HCV) and hepatitis B virus (HBV) infection in hemodialysis (HD) units, serum samples from 607 HD patients and 150 staff members at 11 HD units in Japan were collected, and were compared with those from 704 ordinary blood donors as a control. Serum samples subjected to a first generation ELISA for antibody to HCV (anti-C100-3) and were tested by ELISA for HB surface antigen (HBs-Ag), antibody to HBs-Ag, and antibody to HB core antigen (anti-HBc) as HBV markers. We also tested for HCV infection with a second generation ELISA (for antibodies to C22-3, C33c, and C100-3) in 120 HD patients and 30 staff members at 2 selected HD units. Of 607 HD patients, 104 (17%) were positive for anti-C100-3 and 221 (36%) for HBV markers, indicating a much higher prevalence of HCV and HBV infection among HD patients than among ordinary blood donors (0.9% and 18%, respectively). Of 159 patients without a history of blood transfusion, 17 (11%) were positive for anti-C100-3, showing that HCV infection can be acquired without transfusion. The incidence of anti-C100-3 varied from 0% to 53% at different HD units, and HBV markers varied from 17% to 50%. Our study detected a high prevalence of co-infection with HBV and HCV, suggesting that HCV infection may contribute to chronic liver dysfunction in HD patients. Out of 150 staff members, 3 (2%) were positive for anti-C100-3, whereas 25 (17%) were positive for anti-HBc (indicating prior HBV infection).(ABSTRACT TRUNCATED AT 250 WORDS)

Enzyme-Linked Immunosorbent Assay↗