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T Sonoda

Publications and source records attributed to T Sonoda.

At least 19 recordsLinked to original sources
PubMed1995

Mammalian phosphoribosyl-pyrophosphate synthetase.

PRPP synthetase from rat liver exists as large molecular weight aggregates composed of at least three different components. Cloning of cDNA for the catalytic subunit revealed the presence of two highly homologous isoforms of 34 kDa, designated as PRS I and PRS II. Northern blot analysis showed tissue-differential expression of the two isoform genes. cDNA was expressed in E. coli and studies on the recombinant isoforms showed differences in sensitivity to inhibition by ADP and GDP and to heat inactivation. The rat gene for PRS I has 22 kb and is split into 7 exons. cDNAs for human enzymes were also cloned. Human genes for PRS I and PRS II are localized at different regions on the X-chromosome and their promoter regions were examined. Another component, PRPP synthetase-associated protein of 39 kDa (PAP39), was cloned from cDNA library of the rat liver. The deduced amino acid sequence of PAP39 is remarkably similar to those of PRS I and PRS II. Evidence indicated molecular interaction between PAP39 and the catalytic subunits and an inhibitory effect of PAP39 on the catalytic activity. Expression of the PAP39 gene is tissue-differential like the PRS genes, indicating that the composition of PRPP synthetase may differ with the tissue, hence properties of the enzyme would differ. Further studies on these components and their interaction are expected to reveal various mechanisms governing mammalian PRPP synthetase.

Amino Acid Sequence↗
PubMed1994

Prognostic significance of the overexpression of c-erbB-2 protein in adenocarcinoma of the uterine cervix.

BACKGROUND: The overexpression of c-erbB-2 protein is a prognostic marker in patients with breast cancer. Alteration of the c-erbB-2 oncogene in development of adenocarcinoma of the uterine cervix, an unfavorable gynecologic neoplasm, is unknown. METHODS: To clarify the role of the c-erbB-2 oncogene in adenocarcinoma of the uterine cervix, formalin-fixed, paraffin-embedded tissue sections from 44 cases of cervical adenocarcinoma were immunohistochemically examined for expression of c-erbB-2 protein and for c-erbB-2 gene amplification in DNA by slot blot-hybridization analysis. RESULTS: The expression of c-erbB-2 protein was detected in 34 cases (77%). Strong expression on cell membranes was detected in 11 cases (25%). Most cases with strong membrane expression of c-erbB-2 protein also showed amplification of the c-erbB-2 gene by slot blot-hybridization. Expression of the protein on cell membranes was more often seen at clinical Stage II or III (9 of 23 [39%]) than at Stage 0 or 1 (2 of 21 [9%]) (P < 0.05, Fisher's exact test). Expression of the c-erbB-2 protein was also associated with poorer prognosis of patients with cervical adenocarcinoma by comparison of survival curves (P < 0.005) and by the Cox regression model analysis. CONCLUSIONS: Overexpression of c-erbB-2 protein is associated with amplification of c-erbB-2 gene and frequently occurred in cervical adenocarcinomas of the patients with poor prognoses.

Adenocarcinoma↗
PubMed1994

The superior effect of the combination of FK 506 and deoxyspergualin on rat cardiac allograft survival.

In this present study, the effects of FK 506 and 15-deoxyspergualin (DSG), with respect to dose, timing, and combination, were investigated in an ACI-to-LEW rat cardiac allograft model. FK 506 was administered intramuscularly for 14 days starting on day 0 after grafting, while DSG was given intraperitoneally for 7 days starting on day 0,4, or 7 after transplantation. FK 506 or DSG monotherapy prolonged cardiac allograft survival in dose-dependent manners, and the minimum effective dose for overcoming rejection was 0.1 mg/kg per day in the case of FK 506 and 1.0 mg/kg per day for DSG. The graft survival rate was higher with administration of DSG starting on day 4 on day 0 after transplantation. A low dosage of FK 506 starting on day 0, in combination with DSG starting on day 0 or day 4 (but not on day 7), had a synergistic effect in prolonging allograft survival for 14.0 +/- 3.3 days and 25.4 +/- 8.2 days, respectively. The most effective combination treatment schedule for prolongation of allograft survival was FK 506 starting on day 0 and DSG starting on day 4 after transplantation.

Animals↗
PubMed1994

Light microscopical immunohistochemical study on parathyroid adenoma in primary hyperparathyroidism.

Fifteen adenomatous parathyroid glands obtained from 15 patients with primary hyperparathyroidism were examined both pathologically and immunohistochemically and connected with the clinical data for each patient. Four consecutive sections of the largest section surface of each resected adenomatous parathyroid gland were utilized for 4 kinds of stains, that is, hematoxylin-eosin, Grimelius and the immunohistochemical stains for parathyroid hormone (PTH) and chromogranin A. The results were as follows: (1) The large adenomatous parathyroid glands showed strong reactions to PTH as well as chromogranin A and Grimelius. On the other hand, the parathyroid adenoma obtained from a 9-year-old boy with hypercalcemic crisis showed almost no stain-positive cells for both PTH and chromogranin A. It is assumed that the former phenomenon reflects a substantial storage of secretory granules, while the latter reflects exhaustion of these granules. (2) The normal parathyroid cells in the neoplastic parathyroid glands generally showed stronger reactions to PTH and chromogranin A than neoplastic parathyroid cells. This suggests that normal cells in the neoplastic parathyroid glands may have their release of PTH rather than its synthesis suppressed, and also might support the hypothesis of some authors that chromogranin A or SP-I might contribute to stabilization of PTH or the secretory vesicle.

Adenoma↗
PubMed1993

[Blood level monitoring of FK506 on kidney transplant recipients].

Blood level monitoring of FK506 was performed on 6 kidney transplant recipients. Reproducibility was evaluated on trough and AUC levels in both whole blood and plasma samples. Reproducibility was almost the same degree on both trough and AUC levels and in both whole blood and plasma samples. Trough and AUC levels in whole blood and AUC in plasma were low at the onset of rejection episodes, whereas those were high at the onset of adverse effects by FK506 such as hyperglycemia, hyperkalemia and neurological symptoms. Frequent trough level monitoring is useful to detect kidney transplant rejection and adverse effects by FK506.

Graft Rejection↗
PubMed1992

Promoter regions of the human X-linked housekeeping genes PRPS1 and PRPS2 encoding phosphoribosylpyrophosphate synthetase subunit I and II isoforms.

The 5' regions of the human phosphoribosylpyrophosphate synthetase subunit I and II genes (PRPS1 and PRPS2, respectively) were isolated and sequenced. A comparison of the nucleotide sequences between human and rat PRPS1 genes revealed that the sequences around the transcription initiation sites were conserved over 56 nucleotides, and that a TATA-like sequence, a CCAAT box and three putative Sp1 binding sites were present at almost the same positions in the GC-rich sequences. Two major transcription initiation sites were localized in the human PRPS1, one of the two was located 27 nucleotides downstream from the TATA-like sequence, while the upstream initiation site was in the TATA-like sequence. The promoter region of the human PRPS2 gene was also GC-rich and contained a TATA-like sequence, four Sp1 binding sites and a homopyrimidine stretch. The initiation sites were localized at 90 nucleotides upstream from the ATG initiation codon. Chloramphenicol acetyltransferase (CAT)/promoter fusion assays showed that a 2.0 kb region (human PRPS1) and a 1.1 kb region (human PRPS2) possessed the promoter activities in four cell lines. The CAT activities in the three human cell lines tended to correlate with the steady-state mRNA levels of the PRPS1 and PRPS2 genes. These results suggest that the 5' flanking regions cloned contribute to the cell-differential expression of these two genes.

Amino Acid Sequence↗
PubMed1992

Hepatic resection for a hepatocellular carcinoma larger than 10 cm.

Twenty-one patients with hepatocellular carcinoma (HCC) larger than 10 cm diameter were treated during the 18 year period from 1971 to 1988. The mean tumor size was 13 cm (range 10-18 cm). Nineteen patients (90.5%) had subjective symptoms. Eight patients (38.1%) had alpha-fetoprotein (AFP) levels over 10,000 ng/ml, and in 18 patients (85.7%) the levels were over 20 ng/ml. Nevertheless, only three (14.3%) were detected by AFP. Scintigraphy before 1981 and ultrasonography after 1982 appears to be most helpful for detection of HCC. Nineteen lesions (90.5%) were localized in the right hepatic lobe. Large HCC showed a low incidence of histologically verified concomitant cirrhosis (33%; 7 of 21) and a relatively well preserved hepatocellular function (indocyanine green test; 13.9 +/- 6.6%). Curative resection could be done for all 21 patients. There were three (14.3%) operative deaths. The 1-, 3-, and 5-year survival rates were 72.2, 32.9, and 8.2%, respectively. One patient who underwent a left hepatic lobectomy has survived for over 5 years, with recurrence. There were 14 recurrences (66.7%) in 21 patients: 11 were hepatic and three were in the lungs. In patients with large HCC, surgical resection should be done, provided the clinical status and hepatocellular reserves are adequate.

Carcinoma, Hepatocellular↗
PubMed1992

DNA ploidy of primary hepatocellular carcinoma and pulmonary metastases.

To better comprehend the differences in deoxyribonucleic acid (DNA) content between a primary hepatocellular carcinoma (HCC) and pulmonary metastatic nodules, tissue specimens taken at autopsy of 25 patients who had not received any drugs to treat the malignancy were examined using microspectrophotometry. The DNA distribution patterns were classified into Types I-III, and low (Types I and II) or high (Type III) ploidies, according to DNA distribution. Changes in the DNA content from high to low ploidies, namely DNA ploidy reduction from the primary lesion to pulmonary metastatic lesions, was evident in 9 of the 25 patients (36%), and changes from low to high were noted in 2 of the 25 patients (8%). The remaining 14 (56%) showed no evidence of changes in the DNA ploidy pattern. Reduction of DNA ploidy seen in HCC and its metastatic lesions in the lung may be one of the aspects of clonal evolution or selection mechanisms during the progression of tumor growth and metastasis.

Autopsy↗
PubMed1992

In vivo and in vitro mechanisms of cardiac allograft acceptance in the rat after short treatment with 15-deoxyspergualin.

15-Deoxyspergualin (DSG) has been reported to be a useful immunosuppressive agent already used to inhibit acute rejection in clinical transplantation. In the present study, the survival of heart allograft in rats after a short course of DSG treatment and the mechanisms underlying DSG-induced heart allograft acceptance were studied. Male LEW rats were used as recipients. Male ACI and Wistar rats were used as donors and third-party donors, respectively. Survival of ACI heart grafts in LEW recipients treated with a short course of DSG starting on day 4 after grafting was markedly prolonged, with a mean survival time of 16.6 +/- 5.8 days and 29.8 +/- 3.0 days at doses of 2.5 mg/kg per day and 5 mg/kg per day, respectively. On day 20 after grafting, the mechanism of inducing allograft survival after DSG treatment at a dose of 5 mg/kg per day was analyzed by testing the activation of spleen cells or serum in several assay systems. Spleen cells from DSG-treated rats with surviving heart allografts showed almost no proliferative response against donor strain stimulator cells compared with controls. The cytotoxic activity towards donor strain target cells of spleen cells from DSG-treated rats with surviving heart allografts was lower than that of spleen cells from rats with rejected heart allografts.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Independent association of antibodies against human papillomavirus type 16 E1/E4 and E7 proteins with cervical cancer.

The E4 open reading frame (ORF) of human papillomaviruses (HPVs) is transcribed in abundant mRNAs encoding an E1/E4 fusion gene during the productive infection, and the HPV 16 E7 ORF encodes an oncoprotein detectable in the cell lines derived from cervical carcinoma. We examined 421 human sera, which included 108 samples from the patients with cervical carcinoma, for the presence of IgG antibodies against the HPV 16 E4 and E7 proteins by enzyme-linked immunosorbent assay. Bacterially expressed fusion protein lac-E1/E4 and nonfusion protein E7 were purified and used as antigens. All of the 22 serum samples positive for anti-E7 antibody and the 11 out of 15 samples positive for anti-E1/E4 antibody were from the patients with cervical carcinoma, but only one sample was found to contain both anti-E1/E4 and anti-E7 antibodies. These findings show specific and independent association of these antibodies with cervical carcinoma.

Adenocarcinoma↗
PubMed1992

Thermogenic, thermolytic and body temperature effects of fenfluramine, a 5-hydroxytryptamine agonist, in the domestic fowl (Gallus domesticus).

1. Intramuscular injection of the 5-HT agonist DL-fenfluramine increased the metabolic rate of mature cockerels by about 25% over the following 22 hr. The acute effect, over the 3 hr following injection, attained 40% at 10 degrees C, 35% at 20 degrees C and 25% at 32 degrees C. 2. Heat loss mechanisms (peripheral vasodilatation, postural change and panting) were also stimulated, to an extent which varied with ambient temperature. 3. Food intake, respiratory quotient and locomotor activity were significantly reduced by fenfluramine injection. 4. The opposing effects on heat production and heat loss had an influence on deep-body temperature which varied from a reduction of 0.5 degrees C at 10 degrees C ambient to an increase of about 0.5 degrees C at 32 degrees C. 5. The 5-HT blocker, methysergide, prevented the effects of fenfluramine on both heat production and heat loss for about 5 hr after injection. 6. The autonomic ganglion blocker, hexamethonium chloride, reduced the thermogenic but not the heat-loss effects of fenfluramine. 7. The results suggest that DL-fenfluramine has centrally-occurring but independent effects on heat production and a number of heat loss effectors, and that the heat production effect is mediated by the autonomic nervous system. The effect of fenfluramine on deep-body temperature appears to result from an altered equilibrium between heat production and heat loss.

Animals↗
PubMed1992

Interleukin-6 activity in urine and serum in patients with bladder carcinoma.

To investigate the correlation between interleukin-6 and urothelial neoplasms, interleukin-6 activities in blood and urine samples of patients with bladder carcinoma were measured with a proliferation assay using an interleukin-6 dependent murine hybridoma clone, MH60.BSF2. A total of 43 patients and 15 normal volunteers were entered into this study. All of the patients were examined preoperatively and 26 were reexamined more than 6 days postoperatively to eliminate the effect of surgical injury on interleukin-6 secretion. The interleukin-6 titers in urine and serum increased in accordance with the progression of the tumor stage, and tumor removal induced a remarkable decrease in the titer of urinary interleukin-6. Although the interleukin-6-producing site has not been elucidated yet, our study suggests that interleukin-6 activity in bladder carcinoma patients may reflect the immunoreaction against the tumor in local urothelium.

Adult↗
PubMed1992

A strategy of cystine stone management.

Simple mechanical disintegration of cystine calculi by extracorporeal shock wave lithotripsy and/or percutaneous nephrolithotomy is being performed widely around the world. However, it cannot be denied that the cystine calculus is one of the most difficult stones for mechanical disintegration. We previously reported the oral medical chemolysis of cystine calculi in 1982 and a third of the patients became stone-free. In another third of the patients the cystine component was replaced by apatite during the medical treatment and apatite stones formed in this manner are easily disintegrated. In view of the complications of mechanical disintegration, oral medical treatment for chemolysis should be recommended before simple destruction of cystine calculi.

Adult↗
PubMed1992

The in vitro immunosuppressive effect of deoxymethylspergualin in man as compared with FK506 and cyclosporine.

The effect of deoxymethylspergualin (MeDSG) on in vitro human lymphocyte response was assessed in comparison with FK506 and cyclosporine. Peripheral blood mononuclear cells from normal human volunteers were used for assay of mixed lymphocyte reaction, cell mediated lympholysis, and blastogenesis by PHA, IL-2, and OKT3. MeDSG suppressed only allogeneic stimulation (MLR and CML) and IL-2-induced blastogenesis, not PHA- or OKT3-induced blastogenesis, although the other immunosuppressive agents showed some suppressive effect for all assays. A kinetic study of MLR showed that the suppressive activity did not decrease even when MeDSG was added at day 3 or day 4. The other agents, however, showed a weak suppressive effect when added at a later phase of MLR.

Cyclosporine↗
PubMed1992

FK506-induced kidney tubular cell injury.

Some renal changes associated with cyclosporine, such as tubular vacuolization and glomerular thrombosis, have also been reported with FK506. Furthermore, FK506 therapy is associated with a decrease in glomerular filtration rate and renal plasma flow and an increase in renal vascular resistance. We studied the in vitro tubular cell sensitivity to FK506 in comparison with CsA, the ultrastructural changes induced by FK506 and CsA, and the effect of both drugs on tubular cell growth in vitro. We also investigated whether FK506 and CsA induced endothelin-1 (ET-1) secretion of cultured tubular cells and whether this stimulatory effect coincided with a change in the endothelin systemic synthesis. Exposure of tubular cells to high concentrations of FK506 or CsA (10, 50, 100 microM) induced a time- and dose-dependent cell injury in vitro. The damage induced by FK506 and CsA was characterized by a direct cytotoxic effect on tubular cells, as expressed by release of 3H thymidine from prelabeled cells, N-acetyl-beta-D-glucosaminidase release, and cell detachment. Ultrastructural changes (vacuolizations, swelling, and mitochondrial enlargement) and inhibition of the growth of cultured tubular cells were also observed at high concentrations of FK506 and CsA. Low concentrations of FK506 and CsA (1, 0.1, 0.01, 0.001 microM) were not cytotoxic and induced only a minimal inhibitory effect on the growth of tubular cells in vitro. We demonstrated that FK506 (1, 0.1, 0.01 microM) time-dependently stimulated the secretion of endothelin by cultured tubular cells. CsA 10, 1, 0.1, 0.01 also exerted an enhancing effect on ET-1 secretion in cultured tubular cells. We observed that the concentration of CsA that induced the most important enhancing effect was 10 or 100 times higher than that required for FK506 to observe the same effect. The concentrations of FK506 or CsA that induced ET-1 secretion were not cytolytic for tubular cells in vitro. FK506- or CsA-treated rats showed an increase in serum level of ET-1 in comparison with the control. Through the stimulatory effect on endothelin secretion by tubular cells, FK506 and CsA may induce a perturbation of renal hemodynamics. Concentrations of FK506 and CsA, higher than established serum levels but close to those reached in tissues, are cytotoxic for tubular cells and induced ultrastructural changes and a significant delayed regeneration.

Acetylglucosaminidase↗