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Y Aso

Publications and source records attributed to Y Aso.

At least 181 records · Page 10Linked to original sources
PubMed1991

Inactivation kinetics of enzyme pharmaceuticals in aqueous solution.

The kinetics of enzyme inactivation in aqueous solution of neutral pH were studied for alpha-chymotrypsin, bromelain, and kallikrein. Inactivation of alpha-chymotrypsin and bromelain followed simple first-order kinetics, and the rate constant obtained conformed to the Arrhenius relationship. Kallikrein, however, presented more complicated kinetics of inactivation, which could be described by a kinetic expression combining a reversible and an irreversible pathway. Nonlinear regression analysis suggested that the rate constants conform reasonably well to the Arrhenius relationship. The results suggest that inactivation of enzymes in aqueous solution can be modeled even if the profile is complicated and that the inactivation rates can be predicted based on the relationship between the parameter estimates and temperature.

Bromelains↗
PubMed1991

Trial to induce prostatic cancer in ACI/Seg rats treated with a combination of 3,2'-dimethyl-4-aminobiphenyl and ethinyl estradiol.

In an attempt to induce prostatic adenocarcinoma at higher incidence in a shorter period, we administered diet containing 0.75 ppm of ethinyl estradiol (EE) for three weeks to ACI/Seg rats, which are predisposed to develop a high incidence of microscopic adenocarcinoma of the prostate at higher age. Then, feeding was changed to basal diet and a single subcutaneous injection of 50 mg/kg body weight of 3,2'-dimethyl-4-aminobiphenyl (DMAB) was given two days after the change. We repeated this schedule 10 times. The rats were killed in week 60 of the experiment and subjected to routine autopsy. The average body weight of rats in group 1 given EE and DMAB was lower than that of control rats in group 2. The incidence of adenocarcinoma was not significantly different in the two groups, i.e., 6/74 (8.1%) in group 1 and 2/54 (3.7%) in group 2. The lesions were all microscopic. The incidence of atypical hyperplasia was significantly higher in group 1 at 17 of 74 rats (23.0%) whereas in group 2, it was only 2 of 54 rats (3.7%). Simple hyperplasia was also observed in 25 of 74 rats (33.8%) in group 1, which was significantly higher than that in group 2, where six of 54 rats (11.1%) had this lesion. The reduced growth of animals due to treatments with EE and DMAB probably suppressed the development of prostate cancer in this experiment. Further studies are needed to develop an appropriate model to induce prostate carcinoma at higher incidence in a shorter period.

Aminobiphenyl Compounds↗
PubMed1991

Typing of human polyomavirus JC virus on the basis of restriction fragment length polymorphisms.

JC virus DNA clones from the urine of nonimmunosuppressed Japanese individuals regularly contain an archetypal regulatory sequence which may have generated various regulatory sequences of JC virus isolates from patients with progressive multifocal leukoencephalopathy (PML). In this study, we established 15 new clones from the urine of Dutch, German, and Taiwanese healthy volunteers and patients. Most of these clones contained regulatory sequences essentially identical to the archetypal regulatory sequence. These clones, along with two representative urine-derived clones in Japan and five clones from the brains of PML patients (four established in the United States and one established in Japan), were analyzed with a number of restriction enzymes. We found nine restriction fragment length polymorphisms by which all clones were classified into either of the two types, A and B. Type A contained only clones from the West, while type B contained some from the West and all from eastern Asia. Each type contained both urine-derived and PML-derived clones. Furthermore, there was a close relationship between some urine-derived clones and some PML-derived clones in restriction site mapping analysis. These findings support the adaptation hypothesis which has been postulated to explain the genesis of PML-type JC viruses.

Base Sequence↗
PubMed1991

Sequence rearrangement in JC virus DNAs molecularly cloned from immunosuppressed renal transplant patients.

From nonimmunocompromised individuals, we have recently identified a possible archetypal JC virus DNA sequence from which various regulatory sequences of JC virus isolates derived from patients with progressive multifocal leukoencephalopathy (PML) could have evolved. In this study, we analyzed the regulatory sequences of JCV DNAs cloned from urine samples of a PML risk group (renal transplant patients on immunosuppressive therapy). A number of JC virus DNAs were molecularly cloned from virions excreted in the urine of eight patients. Furthermore, fragments containing the regulatory region were amplified by the polymerase chain reaction and subsequently molecularly cloned from cell-associated JC virus excreted in the urine of two patients. The regulatory regions in all clones were analyzed with restriction enzymes, and those in representative clones were sequenced. We found that clones with the archetypal regulatory sequence were predominant in all urine samples, but a few clones carried regulatory sequences that diverged from the archetypal sequence by deletion or duplication. The finding that sequence rearrangement in the archetypal regulatory region occurs in the course of infection in immunosuppressed hosts is consistent with the adaptation hypothesis which has been put forward to explain the divergence of the regulatory regions in PML-derived JC virus isolates.

Base Sequence↗
PubMed1991

Flow cytometric DNA histograms of paraffin-embedded pheochromocytomas.

We proposed a new classification of pheochromocytomas according to DNA ploidy patterns. Proliferation index (PI = S% + 4C%) might be an alternative to 4C% which was used as a critical marker of DNA nonaneuploid histograms. The follow-up survey revealed that DNA tetraploid with minimum increase of PI could not rule out the substantial possibility of malignancy and the comparison of DNA diploid histograms disclosed that 22 and 0% showed significant increase of the ratio of 4C% to S% under PI and 4C% criteria, respectively. In conclusion, 4C% was more effective and reliable than PI in order to classify DNA nonaneuploid pheochromocytomas.

Adrenal Gland Neoplasms↗
PubMed1991

[Localization of alpha 1-adrenoceptors in hypertrophic prostate].

In order to determine the localization of alpha 1-adrenoceptors in human hypertrophied prostates, in vitro autoradiography was performed on the frozen specimens from 13 enucleated hypertrophied prostates with [125I]-HEAT (iodo-2-[beta-(4-hydroxyphenyl)-ethylaminomethyl] tetralone) and [3H]-prazosin. In vitro autoradiograms showed macroscopically the specific binding site on the areas seemed to the nodular area for [125I]-HEAT, but not so clear specific binding sites for [3H]-prazosin. Microscopic autoradiograms seemed to show binding sites located mainly on the interstitial beneath the gland, and partly on the basement membrane and epithelium of the prostatic gland. Further studies are needed to show clearer specific binding sites of alpha 1-adrenoceptors.

Aged↗
PubMed1991

[Cyclosporine induced nephrotoxicity and juxtaglomerular apparatus in mice].

To elucidate the relationship between Cyclosporine (Cs) induced nephrotoxicity and juxtaglomerular (JG) apparatus, we carried out biochemical and morphological experiments using mice. Adult male ICR strain mice weighing about 40 g were used. The mice were divided into 2 groups: the Cs group (Cs 50 mg/kg/day was orally given for 14 consecutive days) and the control group (olive oil for 14 days). Urine was stored for 24 hours on the day 0, 7 and 14 and urine volume and concentrations of urinary creatinine (u-Cr) and urinary potassium (u-K) were measured in each group. All the mice were sacrificed and examined on the 15th day. Concentrations of serum creatinine (s-Cr), serum potassium (s-K), plasma renin activity (PRA), plasma aldosterone (Ald) were noted in each group. The kidneys were also examined histologically with light and electron microscopes. The Cs group showed significant increases of s-K, PRA and Ald and a significant decrease of creatinine clearance compared with the control group. Histologically, the Cs group demonstrated focal vacuolar changes in the proximal tubular cells and an increase in the number of granules in the JG cells. Each granule of the Cs group was larger than that of the control group. Cs certainly stimulates the renin-angiotensin-aldosterone system and causes consequently a secondary aldosteronism.

Animals↗
PubMed1991

[The urodynamic effects of an alpha 1-adrenoceptor agonist on the bladder and urethra of female dogs].

It has been known that alpha 1-adrenoceptors play an important role in urethral contraction. The incompetence of the urethral contraction is a cause of stress incontinence. We studied the urodynamic effects of a selective alpha 1-adrenoceptor agonist (midodrine hydrochloride) on the bladder and urethra of female dogs. Under anesthesia with intravenous chloralose, four doses (0.03, 0.1, 0.3 and 1.0 mg/kg) of midodrine were administered intravenously and urodynamic studies including cystometry, urethral pressure profilometry and electromyography (EMG) of the external urethral sphincter were performed. The administration of midodrine induced a significant increase of the maximum closing pressure in the proximal portion of the urethra (p less than 0.05 at 0.03 mg/kg and p less than 0.01 at 0.1, 0.3, 1.0 mg/kg). There were no significant changes in the functional profile length, the closing pressure at the external sphincters, the maximum bladder pressure, bladder capacity and bladder compliance. The administration of 0.3 mg/kg or more of midodrine produced a significant increase in the mean arterial blood pressure. After midodrine administration, transient increases in the external sphincter EMG activities were recognized. The activities showed the synergistic pattern during the bladder contractions. In conclusion, lower dose administration of a selective alpha 1-adrenoceptor agonist (midodrine) specifically produced an increase of the closing pressure in the proximal portion of the urethra without affecting blood pressure. These results suggest that midodrine is useful for the treatment of stress incontinence in humans.

Animals↗
PubMed1991

[Lymphocytic subsets of tumor tissue, non tumorous kidney, and the peripheral blood in primary renal cell carcinoma].

Lymphocyte subsets were examined in renal cell carcinoma (TILs), adjacent non-tumor renal tissue and peripheral blood (PBLs) by flow cytometry and histochemistry in eighteen patients with renal cell carcinoma. CD5-positive cells were predominant in the TILs in 14 patients. In the renal cell carcinoma tissue, CD8-positive cells were predominant over CD4-positive cells, resulting in a less than unity ratio of CD4/CF8-positive cells. The lymphocyte number was significantly in adjacent normal renal tissue than in renal cell carcinoma. However, lymphocyte subsets ratios were not significantly different between these two tissues. PBLs showed the same proportions (CD4/CD8 mean 1.9 +/- 0.8) as the previously published healthy controlled data. The proportions of CD8-positive cells were significantly increased (p less than 0.05) and those of CD4-positive cells were also significantly decreased (p less than 0.01) in the TILs. The infiltrating pattern of TILs in 17 patients was divided histochemically into cluster (N = 7), single (N = 4), and mixed types (N = 6). The cluster and mixed types were significantly more common in grade 1 tumors and the single type was more common in the grade 2 tumors (p less than 0.05). The pT3 tumors showed the single type of TIL infiltration pattern, but showed no significant difference. In the cluster pattern of TILs, CD8-positive cells were surrounded by CD4-positive cells. Non-tumorous kidneys showed no infiltration of lymphocytes, except in 2 patients of pyelonephritis. These results suggest that cytotoxic T-cells stained as CD8 play an immunoreactive role against renal cell carcinoma.

CD4-CD8 Ratio↗
PubMed1991

[Histological grading of alveolar type renal cell carcinoma based on architectural variation].

Ninety-two of a total 107 renal cell carcinomas excluding papillary, sarcomatoid and other uncommon histological types were classified into 3 groups based on architectural variations. Statistically analyses were carried out for prognostic significance. Histological criteria of 3 groups were defined as follows. Group I consists predominantly of tubular formations with characteristic cystic change. Group III shows solid proliferation without tubular formations, and Group II shows small alveolar or trabecular structures with inconspicuous tubular formations. According to the survival curves (Kaplan-Meier method), the prognosis of Group I was significantly better than II and III. Ten year survival rate of each group was 88 +/- 7.8% in Group I, 39 +/- 8.8% in Group II, and 0% in Group III. The distribution of T and V stages in the 3 groups were not significantly different. Nuclear grading of Group I and II was not so different, though high grade cases predominated in Group III. Therefore, the present grading of alveolar type renal cell carcinoma based on architectural atypia was considered to be a useful prognostic parameter.

Aged↗
PubMed1991

[Lectins expression of parathyroid glands with primary hyperparathyroidism].

The binding sites of lectins in parathyroid glands were determined by an immunohistochemical method in normal parathyroid gland, hyperplasia, adenoma and carcinoma, the used lectins were commercially available Glycine max (SBA), Concanavalin enciformis (Con A), Triticum vulgaris (WGA), Richinus communis (RCA), Banderiaea simplicifolia II (BSA II) and Arachis hypogaea (PNA). For normal parathyroid glands (2 cases) and hyperplasia (2 cases), WGA and BSA II were stained in cytoplasma and cell membrane. For carcinoma (1 cases), all lectins but BSA II were positively stained. In particular, SBA revealed more stronger stain than any other hystological types. From the staining patterns of lectins, it was suggested that adenomas (22 cases) be divided into one group similar to carcinoma and the others to normal parathyroid gland and hyperplasia. But there was no difference in clinical data of patients between the two groups.

Adenoma↗
PubMed1991

[Vesicoureteral reflux and renal scarring. Report of cooperative study of "Progressive renal disease" of Ministry of Health and Welfare].

196 cases with vesicoureteral reflux (VUR) from multiple centers were analysed to examine the relationship between VUR and reflux nephropathy. The high correlation (p less than 0.01) was observed between reflux and renal scarring. Even in cases in whom VUR was not demonstrated at the time of testing, renal scarring of various degrees was recognized, suggesting either co-existed hypoplastic kidney or pre-existed infection. The renal scarring, but not VUR, had a significant correlation with proteinuria and hypertension. Retrospective analysis shows that the surgical treatment was closely related to the degree of renal scarring but not to the degree of reflux. Renal scarring progressed even when reflux did not become worse, which is probably accounted for by the presence of pyelonephritis. Although frequency of pyelonephritis decreased significantly (p less than 0.01) from 0.60 +/- 0.89 to 0.084 +/- 0.305 times/patient. year after anti-reflux surgery, renal scarring progressed in 13 kidneys (5.8%). Seven of the 13 kidneys became worse due to the surgical failure. The scar progression was recognized in the remaining six kidneys (three patients) including adult cases despite the successful surgical correction of reflux. Our study points to the urged need for a prospective clinical trial designed for the study of the pathological and clinical background of progressive renal failure in VUR.

Adult↗
PubMed1991

[Hyperthermic treatment of benign prostatic hyperplasia by a prostathermer].

Prostate thermotherapy consisting of 6 sessions of intrarectal 60 min irradiation of 915 MHz microwave generated by a prostathermer (Blodan, Isreal) was performed once or twice a week on 30 patients with benign prostatic hyperplasia. Excluding 2 cases who refused further therapy at the first session because of rectal discomfort, 28 cases were evaluated for the efficacy of the treatment. Good or fair improvement in subjective symptoms was observed in 24 (85.7%) of the cases. Nocturia was significantly relieved from 2.9 to 2.0 a night. Among the objective responses, no improvement was achieved as to residual urine or prostate size, while a significant increase of maximum or average flow rate on uroflowmetry was observed. Adverse effects were minor or moderate, including 2 cases of urethral bleeding and rectal discomfort, 2 cases of lower urinary tract infection and 1 case of hypotension, which occurred at the 5th session. The scoring criteria taking into account of both subjective and objective responses showed that the efficacy is good in 10 cases (33.3%) and fair or good in 20 cases (66.7%). These results indicated the usefulness of the prostathermer as one of non-surgical therapies for benign prostatic hyperplasia.

Aged↗
PubMed1991

Stability of vitamin B1 in a commercial multivitamin syrup preparation.

Accelerated stability studies of a commercial vitamin B1 syrup preparation were carried out at 50, 60, 70 and 80 degrees C. The decomposition of vitamin B1 in the preparation followed pseudo-first order reaction kinetics. Apparent decomposition rate constants conformed to the Arrhenius equation. Apparent activation energy and shelf-life at 25 degrees C were estimated to be 24.2 kcal/mol and 3.3 years, respectively.

Dosage Forms↗
PubMed1991

[Significance of serum ferritin level in testicular tumors].

The clinical value of serum ferritin level in patients with testicular cancer was studied. Seven cases of seminoma and nine cases of non-seminoma from 1983 to 1989 were evaluated. The serum levels of ferritin, human chorionic gonadotropin (beta-HCG), alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA) and lactate dehydrogenase (LDH) were estimated before and after treatment. Abnormally high values of serum ferritin before treatment were noted in 4/7 (57%) in seminoma, 3/9 (33%) in non-seminoma and 7/16 (44%) in total. The total rate showing abnormally high values of serum ferritin was lower than that of beta-HCG and LDH. Meanwhile it was the same as that of AFP and higher than that of CEA. Changes in the serum ferritin level did not always correspond with the clinical course. In 3 out of 6 tumor free patients, higher levels of serum ferritin before treatment became normal after treatment. In one patient with a high level of serum ferritin before treatment, the level of serum ferritin remained higher and retroperitoneal lymph node metastasis developed after treatment. In 9 cases with normal serum ferritin level, 7 showed the normal range of ferritin level throughout the treatment course. These findings suggests that in some patients with testicular cancer, the serum ferritin level might serve as a tumor marker indicating the efficacy of the treatment and the tumor recurrence.

Adult↗
PubMed1991

[Analysis of ferritin immunostaining in testicular tumors].

Localization of ferritin in testicular tumors was studied by the immunohistochemical method and the usefulness of ferritin was evaluated compared with the clinical course. Seven cases of seminoma and 9 cases of non-seminoma were used for the study. Formalin-fixed, paraffin-embedded tissue sections were stained by the avidin-biotin complex method. Commercial rabbit anti-human ferritin polyclonal antibody in 1/100 dilution was allowed to react at room temperature for one hour. In normal testicular tissues, the epithelium in germinal cells was not stained for ferritin. In seminomas, some tumor nests were stained for ferritin. Interstitial cells, especially histiocytes, were also stained for ferritin. In stained tumor cells, cytoplasm was stained uniformly. Necrotic cells were not stained. The same findings were obtained in non-seminomas. In metastatic lesions and tumor thrombi in the vessels, some tumor cells were stained as intensely as in the origin. A case was calculated positive if more than 5% of the tumor cells in the specimen were stained. The positive rate in ferritin immunostaining was significantly higher than that of human chorionic gonadotropin (beta-HCG), alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA) immunostaining with the same materials. The specimens from cases with abnormally high serum ferritin level, were stained more intensely than those from cases with normal serum ferritin level. The result suggests that ferritin might be a useful tumor marker in some of testicular tumors.

Adolescent↗