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T Hotta

Publications and source records attributed to T Hotta.

At least 199 records · Page 11Linked to original sources
PubMed1993

[A case of liver hernia protruded from the central tendon of the right diaphragm].

Diaphragmatic hernia is a rare disease. And if the contents of hernia are intestines, the diagnosis is easy. But if those are great omentum or liver, discrimination from the thoracic tumor is difficult. We experienced a case of liver hernia protruded from the central tendon of the right diaphragm. A 6-year-old girl was admitted to our hospital for investigation of an abnormal shadow of the right lower lung filed, pointed out in the chest X-ray examination at school. We diagnosed as a congenital diaphragmatic hernia of the liver. We made a surgical correction and her postoperative course was uneventful.

Child↗
PubMed1993

Erythroid potentiating activity of tissue inhibitor of metalloproteinases on the differentiation of erythropoietin-responsive mouse erythroleukemia cell line, ELM-I-1-3, is closely related to its cell growth potentiating activity.

The erythroid-potentiating activity (EPA) of the tissue inhibitor of metalloproteinase-1 (TIMP-1) was re-examined using ELM-I-1-3, a mouse erythroleukemia cell line, which responded well to erythropoietin. Depletion of pre-existing TIMP-1 from fetal calf serum in culture medium using monoclonal antibody suppressed erythropoietin-induced differentiation as measured by the induction of hemoglobin, commitment assay and globin mRNAs. The removal of TIMP-1 also suppressed the proliferation of ELM-I-1-3 as measured by cell number and de novo DNA synthesis. These changes were reversed by the addition of purified TIMP-1 to the culture medium. Anti-TIMP-1 antibody also blocked both hexamethylene bisacetamide (HMBA)-induced erythroid differentiation and the proliferation of both ELM-I-1-3 and Friend erythroleukemia cells. Considering previous reports analyzing the chemical induction of Friend mouse erythroleukemia cell differentiation, our results suggest that erythropoietin- or HMBA-induced erythroid differentiation might also be coupled with cell proliferation. Our 3H thymidine-uptake experiment shows that TIMP-1 removal was also effective in the inhibition of cell growth of various other cell lines in addition to erythroleukemia cell lines. These results suggest that EPA action of TIMP-1 on erythroid leukemia cell lines is closely related to its activity to promote the cell growth of various cell lines and cells including erythroleukemia cell lines.

Acetamides↗
PubMed1993

Clinical implications of chromosomal abnormalities in 401 patients with myelodysplastic syndromes: a multicentric study in Japan.

It is well known that cytogenetic analysis in patients with myelodysplastic syndrome (MDS) provides information useful in determining their prognosis. Based on the chromosomal results obtained from 401 MDS patients by a multicentric study in Japan, we studied correlations between chromosomal findings and prognosis or leukemic transformation in MDS patients. Patients with complex aberrations (cytogenetic abnormalities at more than three chromosomes), of any subtype, had a poor prognosis; for example, > 60% of patients with refractory anemia (RA) showing complex aberrations died within one year, but only 11% of them developed leukemia. In patients with RA with ringed sideroblasts (RARS), > 70% of those with complex aberrations evolved into the leukemic phase and survived for less than one year, suggesting a biologic heterogeneity in RARS patients. By contrast, about 5% of patients with RA or RARS exhibiting chromosomal findings other than -7/7q-, +8, two aberrations, and complex aberrations, developed leukemia and had a favorable prognosis. Therefore, the presence of chromosome abnormalities alone in patients with RA or RARS is not a factor in predicting leukemic transformation or poor prognosis. In patients with refractory anemia with an excess of blasts (RAEB), the presence of chromosome aberrations at MDS diagnosis affected the occurrence of leukemic transformation (24% versus 43%), however, no particular difference was noted in patients with RAEB in transformation with regard to whether they had chromosome changes or not, and about 60% of them evolved into leukemia. The poor prognosis related to complex aberrations was consistently noted in all MDS subtypes or age-matched groups, indicating that this cytogenetic anomaly is an independent risk factor for a poor prognosis in MDS patients. The duration between MDS diagnosis and development of the leukemic phase and that between the latter and death were significantly shorter in patients with complex aberrations than those without this change. Although the clinical significance of certain chromosomal abnormalities differs among subtypes of MDS, a new scoring system for predicting prognosis by cytogenetic changes, in combination with hematologic parameters, was proposed.

Adolescent↗
PubMed1993

[Cerebral renal and hepatic tissue blood flow during retrograde inferior vena caval perfusion--an experimental study in dogs].

Cerebral tissue blood flow (CBF), renal tissue blood flow (RBF), hepatic tissue blood flow (HBF), and oxygen metabolism have been measured in 8 mongrel dogs which underwent hypothermic (20 degrees C) retrograde perfusion via the inferior vena cava (IVC). IVC perfusion was performed with aortic drainage and cross-clamping of superior vena cava (SVC) at IVC pressures of 20 or 30 mmHg. CBF, RBF, and HBF at 30 mmHg of IVC pressure were 10.4 +/- 6.8, 11.4 +/- 5.5, and 19.2 +/- 11.3 mL/min/100 g. These values were 33%, 47%, and 64% of those observed with a cardiopulmonary bypass and flow rate of 1000 mL/min, and 77%, 112%, and 168% of those observed with retrograde cerebral perfusion via the both internal maxillary veins at 25 mmHg of SVC pressure. Oxygen consumption at this time was 3.78 +/- 1.77 mL/min. CBF, RBF, HBF, and oxygen consumption at 20 mmHg of IVC pressure were 7.7 +/- 4.8, 7.5 +/- 4.7, and 9.9 +/- 4.7 mL/min/100 g and 2.02 +/- 0.72 mL/min, respectively. As IVC pressure increased, CBF, RBF, HBF, and oxygen consumption increased. However, high IVC pressure by the retrograde perfusion was associated with high portal venous pressure, which would cause ascites. IVC perfusion can supply some amount of blood flow to the liver and kidney. It may therefore be advantageous to maintain proper IVC pressure to protect the abdominal organs during systemic arterial circulatory arrest under deep hypothermia.

Animals↗
PubMed1992

Thrombin-induced shape change in human megakaryoblastic leukemic cells, MEG-01, is mediated by protein kinase C.

We investigated the intracellular processes of the shape change in human megakaryoblastic leukemic cells, MEG-01, by platelet agonists. Thrombin induced the formation of many pseudopods. This shape change was also induced by phorbol 12-myristate 13 acetate (TPA) and weakly by Ca2+ ionophore, A23187, but not by ADP, collagen, or epinephrine. Electron microscopy and FITC-labeled phalloidin staining revealed thick submembranous microfilament bundles in the pseudopods of the shape-changed cells by thrombin. Shape change was inhibited by cytochalasin B. Since Ca(2+)-dependent phosphorylation reactions play central role on the initiation of shape change of platelet, we examined the effects of protein kinase C (PKC) inhibitor, H-7, and myosin light chain (MLC) kinase inhibitor, ML-9, on the shape change of MEG-01 cells induced by thrombin, and observed that H-7 potently inhibited thrombin-induced shape change, while ML-9 did not. These results suggest that thrombin-induced reorganization of microfilaments and shape change of MEG-01 cells are mediated by PKC, but not by MLC kinase.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1992

Mutations of p53 gene and their relation to disease progression in B-cell lymphoma.

The alteration of p53 tumor suppressor gene was studied in 48 patients with B-cell lymphoma. A sequential combined technique of polymerase chain reaction-mediated single-strand conformational polymorphism (PCR-SSCP) or reverse transcription (RT)-PCR-SSCP and direct sequencing were used as a simple and sensitive approach to analyze nucleotide changes. By these methods, we identified 8 missense point mutations and 2 codon deletions in 9 of the 48 patients. These mutations were located in or close to the evolutionally highly conserved regions of the p53 gene. Eight of nine patients having p53 gene alterations were in advanced clinical stage (IV). It is the first report of p53 gene mutations in follicular and diffuse lymphoma. These observations suggest that the p53 gene alteration may play an important role in lymphomagenesis and/or disease progression in some types of B-cell lymphoma.

Base Sequence↗
PubMed1992

Defective autologous mixed lymphocyte reaction (AMLR) and killer activity generated in the AMLR in cancer patients.

The autologous mixed lymphocyte reaction (AMLR) and the killer activity generated in the AMLR (AMLR-killer) in the spleen and the peripheral blood of patients with gastric cancer were investigated. The AMLR in cancer patients was suppressed, especially in the spleen, compared to that seen in controls. There was no correlation between AMLR activity and the stage status of the cancer. The cytotoxic activity of AMLR-killer cells against various tumor-cell lines was also suppressed in the spleen, and had a tendency to be suppressed in the peripheral blood of cancer patients. The autologous tumor-killing activity of AMLR-killer cells was developed in cancer patients with high AMLR activity, but was not induced in patients with low AMLR activity. Autotumor killing activity was decreased by the elimination of CD4+ cells, whereas the elimination of CD16+ cells resulted in a marked reduction in cytotoxicity against K562, indicating that the non-specific killer cells which lysed K562 were different from the specific killer cells that lysed autotumor cells. This suggests that AMLR activity is related to the differentiation and proliferation of lymphocytes with specific or non-specific cytotoxic activity and that this activity plays an important role in immune surveillance against tumors.

Adult↗
PubMed1992

Effect of intracarotid infusion of etoposide with angiotensin II-induced hypertension on the blood-brain barrier and the brain tissue.

This study investigated the effects of the intracarotid infusion of etoposide in combination with angiotensin II (AT II)-induced hypertension on the blood-brain barrier (BBB) and brain tissue in rats. Eighty rats were divided into five groups: Group 1, intravenous infusion of AT II to increase arterial blood pressure; Group 2, intracarotid infusion of etoposide at 22.5 mg/m2 for 10 minutes; Group 3, intracarotid infusion of etoposide at 75.0 mg/m2 for 10 minutes; Group 4, intracarotid infusion of etoposide at 75.0 mg/m2 for 20 minutes; Group 5, intracarotid infusion of etoposide at 75.0 mg/m2 for 10 minutes with AT II-induced hypertension. Evans blue staining of the brain was used as a monitor of BBB disruption. Mean arterial blood pressure over the experimental period in Group 1 increased from 86.3 +/- 1.3 mmHg (mean +/- SEM) to 139.0 +/- 2.4 mmHg, and Group 5 from 85.9 +/- 1.8 mmHg to 137.3 +/- 2.4 mmHg. None of the animals in Group 1 and 2 showed any obvious neurological change, while all the animals in Group 3, 4 and 5 exhibited diminished activity as their sole neurological change throughout the course of the experiment. Slight evidence of BBB disruption was seen in only 25% of the animals in Group 1. Significant BBB disruption was found in the animals in Group 2, 3, 4 and 5. No histological change was observed in any animal in Group 1 and 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensin II↗
PubMed1992

Penetration of etoposide into human malignant brain tumors after intravenous and oral administration.

Penetration of etoposide into the cerebrospinal fluid, brain tumor, and brain tissue after intravenous administration was investigated in patients presenting with malignant brain tumors. A relatively low dose (55-65 mg/m2) was used to compare intravenous with oral administration. High-performance liquid chromatography with fluorescence detection was used to evaluate drug levels. Plasma and cerebrospinal fluid levels of etoposide after oral administration (50-150 mg/day) were also studied so as to determine the adequate oral dose for the treatment of malignant brain tumors. The peak plasma concentration after intravenous administration ranged from 7.01 to 10.47 micrograms/ml, varying in proportion to the injected dose, whereas that after oral administration was lower, namely, 1.44-4.99 micrograms/ml, and was unstable when the oral dose was 150 mg daily. The peak cerebrospinal fluid level following either intravenous or oral administration was much lower than the plasma concentration and was influenced by the peak plasma level and the sampling site. The etoposide concentration in cerebrospinal fluid taken from the subarachnoid space and ventricle of patients displaying no tumor invasion and of those presenting with meningeal carcinomatosis and in cerebrospinal fluid taken from the dead space after tumor resection was 0.7% +/- 0.5%, 3.4% +/- 1.0%, and 7.2% +/- 8.5%, respectively, of the plasma concentration. Serial oral administration did not result in the accumulation of etoposide in cerebrospinal fluid. The tumor concentration (1.04-4.80 micrograms/g) was 14.0% +/- 2.9% of the plasma level after intravenous administration, was related to the injected dose, and was approximately twice the concentration detected in the brain tissue. Therefore, a relatively low dose of etoposide injected intravenously penetrates the brain tumor at an efficacious concentration. Our results indicate than an oral dose of 100 mg etoposide be given for malignant brain tumors, as limited penetration of the drug into the intracranial region was observed.

Administration, Oral↗
PubMed1992

Enhancement of tumor cell susceptibility to lymphokine-activated killer cells by treatment with the streptococcal preparation OK432.

We investigated whether tumor cell lysis by LAK cells was augmented by treatment with OK432 in vitro. NK and LAK activity against K562 cells was not enhanced by their treatment with OK432. In contrast, the susceptibility of OK432-treated Daudi and KATO-III cells to lysis by LAK cells was enhanced. Succinate dehydrogenase activity and RNA synthesis were impaired in Daudi and KATO-III cells by treatment with OK432, and moreover the expression of HLA Class I antigen and beta 2-microglobulin was inhibited in OK432-treated KATO-III cells. Thus, it is suggested that the enhancement of the susceptibility of OK432-treated tumor cells with regard to succinate dehydrogenase activity, RNA synthesis, and HLA Class I antigen expression.

Antigens, Neoplasm↗
PubMed1992

Retrograde cerebral perfusion through a superior vena caval cannula protects the brain.

Retrograde cerebral perfusion through a superior vena caval cannula is a new technique for protecting the brain during aortic arch operations. In mongrel dogs (n = 10; 13 to 15 kg) we have performed retrograde cerebral perfusion (300 mL/min) by infusing blood through a superior vena caval cannula with aortic and inferior vena caval drainage. We have measured the cerebral tissue blood flow, oxygen consumption, and carbon dioxide exudation during retrograde cerebral perfusion at normothermia (NT, 37 degrees C) and hypothermia (HT, 20 degrees C) and have compared these values with values obtained in dogs during cardiopulmonary bypass (1,200 mL/min). Cerebral tissue blood flow was measured by the hydrogen clearance method. During retrograde cerebral perfusion about 20% of the superior vena caval perfusate was returned through the aorta and the rest drained from the inferior vena cava. Cerebral vascular resistance during retrograde cerebral perfusion was lower than that during cardiopulmonary bypass (NT, 63.8 +/- 52.5 versus 126.9 +/- 58.4; HT, 28.4 +/- 32.8 versus 69.5 +/- 28.7 x 10(3) dynes.s.cm(-5). Retrograde cerebral perfusion provided half the cerebral tissue blood flow of cardiopulmonary bypass (NT, 14.7 +/- 6.4 versus 34.3 +/- 7.8; HT, 17.6 +/- 5.6 versus 37.2 +/- 10.6 mL/min). Retrograde cerebral perfusion also provided a third of the oxygen (NT, 4.4 +/- 2.1 versus 12.3 +/- 7.1; HT, 1.4 +/- 0.8 versus 4.2 +/- 1.3 mL/min) and discharged 20% of the carbon dioxide (NT, 0.24 +/- 0.08 versus 1.19 +/- 0.58; HT, 0.15 +/- 0.06 versus 0.51 +/- 0.17 mmol/min) when compared with cardiopulmonary bypass. Retrograde cerebral perfusion may reduce ischemic damage during interruption of cerebral blood flow.

Animals↗
PubMed1992

Ganglioglioma of the optic pathway. A case report.

A case of ganglioglioma of the optic pathway associated with congenital exophthalmos and strabismus is presented. Since the tumor extended from the right optic nerve to the right geniculate body, it was diagnosed as an optic glioma before operation. However, optic nerve biopsy showed that the lesion was a ganglioglioma. Although a literature review yielded two previous cases of ganglioglioma of the optic pathway, this is the first case in which the tumor involved the whole optic pathway.

Adolescent↗
PubMed1992

Intracranial germ-cell tumor with synchronous lesions in the pineal and suprasellar regions: report of six cases and review of the literature.

The features of intracranial germ-cell tumor with synchronous lesions in the pineal and suprasellar regions (GCTSPS) in six patients were investigated. GCTSPS accounted for 12.8% of all germ-cell tumors (GCT) in our brain tumor study group. In all cases, the initial symptoms were attributable to the suprasellar lesion, and symptoms due to the pineal GCT developed only after admission. Five of the six cases were histologically diagnosed as germinoma. In all cases, tumors of both regions disappeared after irradiation, resulting in no recurrence for an average of 55.3 months. Our experience and reports in the literature suggest that GCTSPS is highly sensitive to radiation in most cases, although some reports indicated that recurrence is frequent after radiation therapy alone. It is suggested that histological diagnosis in one of the GCTSPS lesions is undertaken to make a plan for the following treatment.

Adolescent↗
PubMed1992

Chemosensitivity testing of fresh human gastric cancer with highly purified tumour cells using the MTT assay.

A major problem associated with the chemosensitivity testing of fresh human tumour cells using the MTT assay is the contamination of nonmalignant cells in the tumour tissues. Highly purified fresh human gastric cancer cells could be obtained from 43 solid tumours and eight malignant ascites for the MTT assay. The success rate of the MTT assay was 87.9% (51 of the 58 cases), and the purity of tumour cells was greater than 90% after separation on Ficoll-Hypaque and Percoll discontinuous gradients in primary, or metastatic lesions, and also ascites. Cisplatin, mitomycin, and doxorubicin were more potent drugs than etoposide and 5-FU against gastric cancer cells. The chemosensitivity in differentiated cancer was equivalent to that in non-differentiated cancer. Twenty of the 51 patients with gastric cancer had evaluable lesions, and they received chemotherapy according to the results of the MTT assay using highly purified tumour cells. A clinical response was obtained in 12 of these 20 patients (response rate: 60.0%; five with complete response, seven with partial response).

Adult↗
PubMed1992

Three human osteosarcoma cell lines exhibiting different phenotypic expressions.

to elucidate the differences in histological features and biological behavior of osteosarcomas, three human osteoblastic-type osteosarcomas were studied in vitro and in nude mice. The secretory processing and extracellular fiber formation of type I collagen proved to be the most important factor in bone formation in the osteosarcomas. Alkaline phosphatase also seemed to be important. However, we were unable to find any particular protooncogene abnormalities which could have been implicated in the occurrence or biological behavior of these osteosarcomas.

Alkaline Phosphatase↗