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Biomedical subjects

T Kawaguchi

Publications and source records attributed to T Kawaguchi.

At least 253 records · Page 14Linked to original sources
PubMed1995

Purification and some properties of six chitinases from Aeromonas sp. no. 10S-24.

Six chitinases were purified from a culture supernatant of Aeromonas sp. no. 10S-24 by ammonium sulfate precipitation, DEAE-Sephadex A-50, Butyl-Toyopearl 650M, and chromatofocusing. These enzymes were most active at pH 3.5-4.5 and the optimum temperature were 50 degrees C. The molecular weights of the enzymes were 89,000 to 120,000 from SDS-polyacrylamide gel electrophoresis. N-Terminal amino acid sequences of the enzymes were similar to that of chitinase I.

Aeromonas↗
PubMed1995

Effects of repeated doses of compound E for 4 and 9 weeks on the male reproductive organs.

Results of two toxicity studies of Compound E, which is an anticancer drug, on male reproductive organs and fertility by oral repeated dosing at dose levels of 12.5, 25 and 50 mg/kg/day for 4 and 9 weeks in rats were compared. After repeated dosing, the male fertility was studied by mating with untreated female animals. At the dose of 50 mg/kg/day in the 4-week study, Compound E significantly decreased testes weight and number of epididymal sperm, caused histopathological changes in the testis and epididymis characterized by decreased germ cells, but did not affect fertility. The dose of 25 mg/kg/day in the 9-week study caused reduction in epididymal weight and number of epididymal sperm and histopathological changes in the testis. The dose of 50 mg/kg/day in the 9-week study was lethal and caused more prominent toxic effects in the reproductive organs and loss of fertility. The present studies suggest that the order of sensitivity of parameters on male reproductive organs is as follows; histopathological examination = organ weight > number of sperm in epididymis > pregnancy index> copulation index. Further, 4-weeks repeated dosing is of sufficient duration to predict adverse effects of test compounds.

Animals↗
PubMed1995

[Renal cell carcinoma in a patient with malignant lymphoma: a case report].

This is a case report of a 51-year-old male in the late stage of malignant lymphoma who presented with pathological fracture renal cell carcinoma secondary to metastatic. He underwent right nephrectomy followed by immunotherapy consisting of interferon alpha and some cytokines. According to his condition and extension of the disease, OK-432, interleukin-2 and interferon gamma were combined. He was also given irradiation to the bone metastases. He died of progressive disease 8 years and 6 months after the initiation of interferon alpha therapy. The autopsy revealed evidence of pancreatic involvement with renal cell carcinoma and malignant lymphoma as well. Malignant lymphoma also infiltrated into the mesentery and left femur. We reviewed other reports regarding multiple malignant tumors associated with renal cell carcinoma and discussed the occurrence of malignant lymphoma in renal cell carcinoma patients.

Carcinoma, Renal Cell↗
PubMed1995

Synthesis and investigation of N4-substituted cytarabine derivatives as prodrugs.

Esters of Cytarabine-N4-carboxylates 2a-i and succinamates 3a-f were synthesized as prodrugs of cytarabine (Ara-C) with the aim of developing improved derivatives for oral or parentral administration. At pH 2 series 2 showed relative higher stability than 3, while both series of esters revealed matched stability at pH 7. All esters were susceptible to enzymatic hydrolysis by rat plasma and liver homogenate with half lives ranged from 0.14 h to 12 d, and showed improved stability against cytidine deaminase. A parabolic relation was shown between Kobs of enzymatic hydrolysis and Vw. All compounds are more lipophilic than the parent drug, Ara-C.

Animals↗
PubMed1995

[On time-frequency analysis at mid-QRS stage on body surface electrocardiogram].

The advanced technology in signal processing has been utilized for recording high resolution electrocardiogram. It has presented some new valuable informations, possibly reflecting electrical characteristics of myocardium. Detecting ventricular late potential is practical, however, it uses only part of high resolution signals, because of difficulty of dividing into higher frequency components. Therefore, high resolutional signals were analyzed using numerical filter in order to detect and verify higher frequency components at mid-QRS stage on body surface electrocardiogram. Precordial signals were summation-averaged and underwent narrow peak filtering using various peek frequencies increasing stepwisely between 50 Hz and 400 Hz. In conclusion, this minutely analyzing system was able to pick up valuable informations in mid-QRS stage signal. For example, harmonization of peek phases in several frequencies at QRS complex had gaps that suggested abnormality of local myocardium.

Arrhythmias, Cardiac↗
PubMed1995

[Relationship between health services and medical care expense].

The relationship of health services for the elderly to medical care expenses for persons over 40 in age was studied by examining data for fiscal year 1992 in 393 municipalities among the municipalities throughout the country where actual conditions have been surveyed. Analysis was by multiple regression analysis. Results showed that medical expenses for every disease were lower in the municipalities which had a higher rate of execution of general health examinations, stomach cancer examinations, and home-visit guidance. This tendency was particularly remarkable in the case of diseases of the circulatory system. In contrast, medical care expenses were high in the municipalities which had a higher demand rate for medical counseling or a higher rate of attendance in health consultation. However the relation of rate of execution of functional training, or attendance rate at the health education sessions, or the rate of performance of detailed examinations was not clear.

Adult↗
PubMed1994

Persistence of affected T lymphocytes in long-term clinical remission in paroxysmal nocturnal hemoglobinuria.

Long-term clinical remission of more than 10 years is rarely seen in paroxysmal nocturnal hemoglobinuria (PNH). Affected blood cells in PNH lack glycosylphosphatidylinositol (GPI)-anchored membrane proteins such as decay-accelerating factor (DAF) and CD59. We performed a flow cytometric analysis of circulating blood cells obtained from two patients with PNH who had been in clinical remission for more than 10 and 25 years, respectively. Affected cells with the PNH phenotype were demonstrated only among T-lymphocytes. Persistent affected T cells were negative for the CD52 protein only, this protein being a GPI-anchored lymphocyte marker without complement regulatory activity. The persistence of the affected T cells may be explained either by an inherently long life span after the disappearance of the PNH stem cell or by insidious production at a subclinical level by affected stem cell. In either event, detection of affected T cells, especially CD52-negative T cells, may be useful for the evaluation of long-term clinical remission in PNH.

Adrenal Cortex Hormones↗
PubMed1994

Adrenomedullin, a newly discovered hypotensive peptide, is a potent bronchodilator.

The present study was designed to examine the effect of adrenomedullin (AM), a novel vasorelaxant peptide originally isolated from human pheochromocytoma, on histamine- or acetylcholine-induced bronchoconstriction in anesthetized guinea pigs in vivo. AM significantly inhibited acetylcholine-induced bronchoconstriction in a dose-dependent fashion. AM also significantly inhibited histamine-induced bronchoconstriction, but 10(-10) M AM had no significant inhibitory effect on this response. We also found that AM induced a long-lasting bronchodilator response, while isoproterenol induced transient bronchodilation. These preliminary findings suggest that AM may play important roles in airway function.

Acetylcholine↗
PubMed1994

Interleukin-2-dependent T-cell lines established from paroxysmal nocturnal hemoglobinuria patients.

Peripheral blood T lymphocytes obtained from two patients with paroxysmal nocturnal hemoglobinuria (PNH) were immortalized with human T-lymphotropic virus type 1 (HTLV-1). These cells showed interleukin-2 (IL-2)-dependent cell growth in culture. Cell surface analysis showed that they had the phenotype of a helper/inducer T subset that was positive for CD2, CD3, and CD4, but negative for CD8, similar to adult T-cell leukemia cells induced by HTLV-1. These cell lines lacked glycosylphosphatidylinositol (GPI)-anchored proteins, CDw52, CD55 (decay-accelerating factor; DAF), and CD59 on the cell surface, whereas intracellular DAF protein was detected. These T-subset cell lines with a PNH phenotype did not synthesize GPI anchor, whereas a control cell line, similarly prepared from the T cells of a healthy volunteer, produced the anchor. The control cells expressed CDw52, DAF, and CD59 on the cell surface and showed the phenotype of a helper/inducer subset. Southern blot analysis confirmed the clonality of each cell line. These CD4+ T-cell lines with a PNH phenotype and a subset-matched control counterpart could be a useful model for PNH investigation.

Antigens, CD↗
PubMed1994

Establishment and characterization of human cell lines from a serous papillary adenocarcinoma of the endometrium.

Two cell lines, SPAC-1-L and SPAC-1-S, derived from a human serous papillary endometrial adenocarcinoma, have been established and repetitively subcultured as a monolayer culture for over 3 years through 144 passage generations. Each of the two cell lines is a subline derived from one original tumor. They have been independently subcultured from the primary culture dishes without any attempt to clone subpopulations and were further characterized with regard to morphology, growth kinetics, tumor marker production, karyotype, and tumorigenicity. These studies indicated that the SPAC-1-L and -S cell lines are different from each other in some cell properties such as morphological character, growth kinetics, and tumor marker productions. Compared with cell lines from a serous papillary endometrial carcinoma that has been previously reported in the literature, our two cell lines are more tumorigenic on nude mice (100%), which possibly correlates with the unusually aggressive biological behavior of the original tumor. In addition, implanted nude mouse tumors, especially the tumor derived from SPAC-1-S cells, retained many characteristics of the original tumor and histologically closely resembled the original serous papillary adenocarcinoma. Since serous papillary carcinoma is a clinically aggressive histological variant of endometrial adenocarcinoma with a significantly poor prognosis, these SPAC-1-L and -S cell lines should prove useful in future studies of the extremely aggressive biological behavior and unique morphology of this tumor.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1994

The long-term growth rate of residual acoustic neurinomas.

The growth rate of 19 residual acoustic neurinomas was examined in a long-term follow-up study (median, 10 years; range, 5 to 17 years) following intracapsular removal. Of these, 10 (53%) had regrowth, three (16%) showed regression, and six (32%) were unchanged. The 10 acoustic neurinomas showing regrowth were divided into two categories, either solid or cystic, according to computed tomographic findings. Five acoustic neurinomas with cyst formation showed rapid regrowth, with the tumour doubling time ranging from 0.15 to 5.0 years (median, 4.5 years), and required re-operation. Five solid tumours showed slow regrowth, with the tumour doubling time ranging from 9 to 34 years (median, 15 years). Although cyst formation is a major factor in rapid regrowth, residual acoustic neurinomas without cyst formation have a slower growth potential. In this study, 74% of the residual acoustic neurinomas have never required re-operation. It is advisable to choose intracapsular removal if there is major risk of neurological deficits.

Adult↗
PubMed1994

Cell surface laminin-like substances and laminin-related carbohydrates of rat ascites hepatoma AH7974 and its variants with different lung-colonizing potential.

Rat ascites hepatoma AH7974 cells strongly expressed antilaminin antibody-reactive substances (laminin-like substances) and Griffonia simplicifolia isolectin B4 (GS)-reactive carbohydrate (alpha-D-galactose; alpha-Gal) on their cell surface. The alpha-Gal expression was not apparently influenced by the pretreatment of cells with methanol. The cell membrane laminin-like substances has approximate molecular weights of 150, 62 and 56 kDa in denaturating reducing conditions, of which the 62 and 56 kDa bands were stained with GS. The cell membrane molecules bearing alpha-Gal were 62 and 56 kDa and were stained with antilaminin antibody. Therefore, the major molecules bearing alpha-Gal residues of AH7974 cell membrane are considered to be laminin-like substances. To determine the role of the substances in metastasis, we selected four cell lines (74AD, 74AD-f, 74FL, 74FL-a) from AH7974 in culture. 74AD and 74FL-a are adherent lines and 74AD-f and 74FL are floating lines. All of these cell lines strongly expressed laminin-like substances, but a marked difference was found in expression of alpha-Gal, which was most strongly expressed by 74FL, followed by 74AD, and rarely by 74AD-f and 74FL-a; the staining intensity was positively correlated with their experimental lung-colonizing potential. Cell membrane laminin-like substances were 200, 97, 62, 56 and 46 kDa and among them 62 and 56 kDa molecules were glycosylated with alpha-Gal. The pretreatment of 74FL cells with antilaminin antibody or with human type A serum (containing natural antibody to alpha-Gal epitope) depressed remarkably the lung-colonizing potential of the cells. These results suggest that the expression of 62 and 56 kDa laminin-like substances with alpha-Gal residues on tumor cell surfaces is one of the determinants associated with lung-colonizing potential of these cells.

Animals↗