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Biomedical subjects

Y Tsuruta

Publications and source records attributed to Y Tsuruta.

At least 91 records · Page 5Linked to original sources
PubMed1992

Successful pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension associated with anticardiolipin antibodies: report of a case.

Chronic pulmonary thromboembolism with pulmonary hypertension is a rare but most unique syndrome in the broad spectrum of pulmonary embolism. This report describes a successful pulmonary thromboendarterectomy performed for a totally occluded right pulmonary artery on a 43 year old man who presented with positive cardiolipin antibodies. The surgery was performed through a median sternotomy with cardiopulmonary bypass and intermittent periods of deep hypothermic circulatory arrest. We are convinced that this method allows for complete removal of the thrombotic obstruction and should be the procedure of choice for patients with very proximal obstruction of a pulmonary artery.

Adult↗
PubMed1992

[Flow cytometric analysis of DNA ploidy in nasosinal papilloma].

Using paraffin embedded specimens taken from 32 patients with histologically benign nasosinal papillomas, we conducted nuclear DNA analysis by flow cytometry and studied the biological degree of malignancy in this disease. Aneuploidy, which is frequently observed in malignant tumors was not seen in any of these nasosinal papilloma cases. Age did not affect either S+G2M % or polyploid %, two parameters that reflect cell proliferation capacity. Both parameters, S+G2M % and polyploid %, were higher in inverted papillomas which are more likely to become malignant than epithelial papillomas. In recurrent cases of nasosinal papilloma both S+G2M % and polyploid % were higher than in nonrecurrent cases. Moreover, the polyploid % was significantly different, supporting speculation that this can be used as a parameter for predicting recurrence of nasosinal papilloma.

Cell Nucleus↗
PubMed1992

[Clinical effects of six-month short time biofiltration].

The clinical effects of six-month short time biofiltration (SBF) were evaluated using a B-A-B' study (B, B': conventional bicarbonate hemodialysis; CBHD, A:SBF) in ten patients maintained on CBHD three times a week. An F80 hemodiafilter (1.9 m2, polysulfone, Fresenius) was used. In addition to routine clinical parameters for a patient on regular dialysis treatment, plasma von Willebrand factor antigen (vWF) (an index of stimulation of vascular endothelium), and the methylguanidine/creatinine ratio (MG/Cr) and malondialdehide (MDA) (indices of the levels of oxygen radicals), were evaluated. Nine patients completed the study, one patient dropping out at the 12th week of A because of muscle cramps during SBF. The treatment time was 2 hours in six cases and 2.5 hours in three cases. The mean blood flow rate was 280 +/- 42 (SD) minutes. Using the urea kinetics model, the mean KT/V was 1.26 +/- 0.28, and the mean protein catabolic rate was 1.22 +/- 0.18 g/kg body weight/day at the end of A. No change in ultrafiltration, blood pressure, cardiac function (assessed by echocardiography), CTR, human atrial natriuretic peptide, total protein, albumin, uric acid, serum creatinine, sodium, calcium, inorganic phosphorus, vWF, or MDA was found between each period. Blood urea nitrogen, c-PTH, and MG/Cr increased during the A period. Serum magnesium and beta-2 microglobulin decreased during the A period. Blood gas results, on the whole, did not change. In a patients, however, acidosis gradually developed. An increase in substitution fluid from 5 L/session to 7.5 L/session improved the acid-base balance in that patient. In conclusion, SBF is as effective as CBHD in removing small molecules and maintaining cardiocirculatory status, and is superior to CBHD in removing beta 2-microglobulin and is less stimulative to the endothelium than CBHD.

Adult↗
PubMed1992

Constitutive expression of leukemia inhibitory factor (LIF) mRNA and production of LIF by a cloned murine thymic stromal cell line.

We have found that normal mouse thymus expressed mRNA for leukemia inhibitory factor (LIF), suggesting the presence of cell component(s) in the thymus that produces this cytokine. High levels of mRNA for LIF were observed to be constitutively expressed in the murine thymic stromal cell clone, MRL104.8a. This stromal cell clone produced potent magnitudes of LIF activity in its culture supernatant. These observations imply that LIF may also exert its growth/differentiation-regulating effect in the thymus. Thus, this thymic stromal cell clone provides a tool for investigating potential roles of LIF in the intrathymic T cell development.

Animals↗
PubMed1991

Glucocorticoid treatment reduces prostacyclin synthesis in response to limited stimuli.

Dexamethasone 21-acetate (DMS 21-A) time- and dose-dependently suppressed bradykinin-stimulated prostacyclin synthesis in porcine aortic endothelial cells. The suppression was more prominent in the presence of pertussis toxin, which by itself could enhance bradykinin-induced prostacyclin synthesis. The DMS 21-A treatment diminished prostacyclin synthesis also in response to vasopressin. In contrast, it did not affect prostacyclin synthesis in response to arachidonic acid or A23187. Melittin-induced prostacyclin synthesis was reduced only at low doses (1-7 x 10(-7) M). The suppression of bradykinin-induced prostacyclin synthesis by DMS 21-A was completely blocked by cycloheximide. DMS 21-A had no effect on the cellular level of lipocortin I protein, but increased the anti-phospholipase A2 activity in EDTA extracts of the cells. These results suggest that the DMS 21-A treatment induces phospholipase A2 inhibitor protein(s) other than lipocortin I and reduces prostacyclin production in response to limited stimuli.

Animals↗
PubMed1991

[Flow cytometric analysis of DNA content in paraffin-embedded tissue in head and neck cancer (the second report)--primary lesions of laryngeal cancer].

Flow cytometric analysis of DNA content using paraffin-embedded materials has become an important diagnostic, as well as prognostic, method for clinical pathology and investigative oncology. DNA content as measured in paraffin-embedded materials is closely related with that obtained from fresh specimens. This method also permits retrospective analysis on a lot of cases and studying different specimens of a tumor for intratumor heterogeneity. Flow cytometry was used to investigation of the DNA distribution in biopsy specimens from 30 patients with squamous cell carcinoma of the larynx. These patients had initially treated in our institute in the period from 1986 to 1988 and followed for two to four years. A modification of Hedley's method was used to prepare paraffin-embedded materials. DNA histogram were assessed in terms of DNA index (DI). The coefficient of variation for determination of DI ranged 4.2 to 13.7% (mean 7.8 +/- 2.4%). Using infiltrated lymphocytes and mesenchymal cells as an internal standards, aneuploid DNA histogram were found in 13 of 30 specimens (43.3%). DI ranged from 1.05 to 1.22. There was no significant correlation between DNA content and sex, age, tumor size, staging or treatment. The aneuploidy was found in 2 of 17 cases with well differentiated tumor (11.8%), 10 of 12 with moderately differentiated tumor (83.3%), one with poorly differentiated tumor (100%). 11.8% of patients with diploid tumor cells had recurrence during the interval of observation, compared to 38.5% of those with aneuploid tumor cells (p less than 0.05). In T1 lesions of glottic cancer aneuploid group had a significantly lower local control rate than diploid group (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Flow cytometric analysis of DNA content in paraffin-embedded tissue in head and neck cancer--evaluation of malignant potential and carcinogenic process of nasoparanasal tumor].

Flow cytometric analysis of DNA content from paraffin-embedded material has become an important diagnostic and prognostic method in clinical pathology and investigative oncology. We analyzed nuclear DNA content in order to detect possible alternations in DNA histogram as an indicator of malignant potential and carcinogenic process of head and neck tumor. DNA histograms were evaluated by three parameters; DNA aneuploidy, S + G2M% : rate of S and G2 + M phase cells as a parameter for growth kinetics, and polyploid%: rate of more than tetraploid cells as a parameter of nuclear atypia. We took a simple method for the selection of tumor area in paraffin blocks using a consecutive section stained with hematoxylin-eosin as a diagnostic guideline. This technique can be used either to enrich the sample to be analyzed with aimed area or to analyze histopathologically different compartments of the tumor. We compared the result of fresh and fixed specimens in 20 materials. DNA aneuploidy was found in both specimens of the same two carcinomas and there was a close relationship between them in S + G2M% (p less than 0.01) and polyploid% (p less than 0.05). We studied two cases of maxillary carcinoma with coexisting inverted papilloma as precancerous lesion. In one case S + G2M% and polyploid% were 16%, 1.15% in nasoparanasal papilloma, 20.5%, 4.0% in papilloma with atypia, and 33%, 8.25% in carcinoma, respectively. In the other case those were 3%, 0.1% in transitional papilloma, 8%, 0.9% in inverted papilloma, and 13%, 4.0% in carcinoma, respectively. There was positive correlation between these two parameters and histopathological grade. Finally we analyzed nuclear DNA content from fixed specimens in three groups; 33 papillomas, 15 maxillary carcinomas and 23 normal epithelia. Mean values of S + G2M% and polyploid% were as follows: 2.1%, 2.6% in normal epithelia, 19.6%, 8.9% in papillomas, and 34.8%, 18.1% in carcinomas. There was statistical significance between three groups (p less than 0.01). DNA aneuploidy was only found in 6 of 15 carcinomas (40%). The results demonstrated that S + G2M% and polyploid% were significantly compared with the histopathological grade of atypia and DNA aneuploidy was a marker of carcinoma. We suggest that DNA histogram is a good indicator for biological activity and that the increased S + G2M% and polyploid% may indicate carcinogenic process. We also suggest that tumor progression may lead to acquired genetic variability and DNA aneuploidy.

Aged↗
PubMed1991

[Surgical results of pulmonary thromboendarterectomy for chronic pulmonary thromboembolism].

Chronic pulmonary thromboembolism may produce severe respiratory insufficiency and progressive pulmonary hypertension resulting in an intractable right ventricular failure. Although the pathogenesis of this syndrome has not been completely understood, medical treatment usually has little effect and only surgery can be a life saving remedy. Since 1986, seven patients with this syndrome have had pulmonary thromboendarterectomy at the First Department of Surgery, Chiba University Medical Center. Surgery is indicated mainly for patients who present with a mean pulmonary arterial pressure greater than 30 mmHg. All procedures were performed through a unilateral thoracotomy with a cardiopulmonary bypass on stand-by use. Two patients (#1 and #6) needed bilateral surgery which was carried out in two stages, in the remainder only a right side being operated on. When a major pulmonary artery was clamped, the systolic pulmonary arterial pressure rose to equalize or even exceeded that of systemic artery, however since no further hemodynamic deterioration was observed, cardiopulmonary bypass was not used in any case. Although the key feature of this procedure is commonly said to establish an exact cleavage plane between thrombus and arterial wall, it can be carried out without difficulty through thoracotomy approach. Grasping the thrombus, blunt dissection is further proceeded until the entire thrombotic material comes free as a cast of the vessels. All patients survived the operation without major complications including severe reperfusion pulmonary edema. Postoperative catheterization, performed one month following surgery, demonstrated a marked reduction of pulmonary arterial pressure with significantly reduced pulmonary arterial resistance (PAR).

Adult↗
PubMed1990

Enhancement of bradykinin-induced prostacyclin synthesis in porcine aortic endothelial cells by pertussis toxin. Possible implication of lipocortin I.

Bradykinin-stimulated prostacyclin synthesis in porcine aortic endothelial cells was enhanced by pretreatment of the cells with pertussis toxin or islet-activating protein (IAP) for 5 hr or longer. Although ADP-ribosylation of a protein with a molecular weight of 41-42 kD in the cell membranes was completed by 3 hr after the addition of IAP into the incubation medium, there was good correlation between enhancement of bradykinin-induced prostacyclin synthesis and ADP-ribosylation of the IAP substrate over a wide range of IAP concentrations. Furthermore, even if IAP was removed from the incubation medium at 3 hr, bradykinin-induced prostaglandin synthesis at 24 hr was still potentiated. Cycloheximide and actinomycin D enhanced bradykinin-induced prostacyclin synthesis and apparently blocked the effect of IAP. Since this result suggested the involvement of an inhibitor protein(s) of prostacyclin synthesis in the IAP effect, we studied the effect of IAP on the level of lipocortin I which is known to inhibit phospholipase A2. Western and Northern blot analyses revealed that IAP decreased the amounts of protein and mRNA of lipocortin I. These results suggest that the enhancement of bradykinin-induced prostacyclin synthesis by IAP is associated with a decrease in the level of lipocortin I.

Adenosine Diphosphate Ribose↗
PubMed1990

The role of lipocortin I in macrophage-mediated immunosuppression in tumor-bearing mice.

The soluble mediators and/or mechanisms involved in immunosuppression in tumor-bearing hosts are not well characterized, although macrophages have long been recognized as major participants. We have investigated the role of lipocortin I, a phospholipid-binding protein, in macrophage-mediated immunosuppression in tumor-bearing mice. Proliferation of splenic lymphocytes in response to the mitogens (PHA, Con A, LPS, and PWM) was severely suppressed in tumor (Sqc-NH-1 carcinoma)-bearing mice. This immunosuppression was associated with a decrease in T and B lymphocytes and an increase in macrophages in these spleens. Mac-2+ macrophages were found only in spleens from tumor-bearing mice. Splenic macrophages from tumor-bearing, but not normal, mice were responsible for this immunosuppression, as revealed by negative and positive selection experiments. The levels of lipocortin I mRNA expression were markedly increased in peripheral blood cells from tumor-bearing mice as compared with those from normal mice. Lipocortin I mRNA was strongly induced in splenic mononuclear cells from tumor-bearing mice. Furthermore, these cells displayed increased expression of lipocortin I protein, as judged by Western blot analysis with polyclonal anti-lipocortin I serum. Some nonimmune organs such as the heart, submaxillary gland, muscle, and bladder also displayed increased levels of lipocortin I mRNA expression in tumor-bearing mice. Mac-2+ macrophages among the splenic mononuclear cells in tumor-bearing mice expressed lipocortin I mRNA, as judged by negative and positive selection experiments. Most of these Mac-2+ macrophages also had Mac-1 and Mac-3 Ag. Lipocortin I protein was increased in the serum of tumor-bearing mice as compared with normal mice. The culture supernatants of splenic cells from tumor-bearing mice suppressed the mitogenic responses of splenic cells from normal mice, and addition of anti-lipocortin I antiserum inhibited this suppression. Furthermore, recombinant mouse lipocortin I suppressed mitogenic responses of splenic cells from normal mice. In summary, Mac-2+ macrophage-derived lipocortin I was largely involved in immunosuppression in tumor-bearing mice.

Animals↗
PubMed1990

Constitutive expression of interleukin-7 mRNA and production of IL-7 by a cloned murine thymic stromal cell line.

Mouse interleukin-7 (IL-7) cDNA was cloned from mouse thymic stromal cell clone MRL 104.8a using a polymerase chain reaction (PCR) technique and expressed in COS-7 cells. The resulting recombinant interleukin-7 (rIL-7) supported the proliferation of mouse antigen-specific helper T cell (Th) clone 9-16 in the absence of IL-2 and antigen as well as mouse pre-B cell line DW34. It was also found that high levels of the mRNA for IL-7 were constitutively expressed in the MRL104.8a cells, and a potent amount of IL-7 was produced in its culture supernatant. These results provide the evidence for constitutive expression of IL-7 mRNA and for production of IL-7 by thymic stromal cells that have a critical role in intrathymic T cell development. The results are discussed in the context of the functional and molecular relationship between IL-7 and the previously described cytokines produced by thymic stromal cells.

Animals↗
PubMed1990

[Three dimensional culture of human salivary gland using irradiated collagen gel embedding technique].

Embedding culture was performed on normal salivary gland cells from five subjects using 0.2% irradiated collagen gel. Collagen was collected from rat tail tendon and gelatinized at the final concentration of 0.2%. D-MEM added BSA (5mg/ml), insulin (10 micrograms/ml) and EGF (5 micrograms/ml) was used as a serum-free medium. Within the collagen gel, the cells were found to grow in a branch-like pattern, and then to form a lot of radial duct-like structures containing alcian blue positive secretions. Immunohistochemical observation of myoepithelial cells with monoclonal antibody from human mammalian cancer suggested that these cells play an important role in the process of glandular ducts formation. Salivary gland cells being able to grow in collagen gel in a very similar fashion to in-vivo condition, the present collagen gel embedding culture is useful for morphological or functional studies on salivary gland cells.

Animals↗
PubMed1990

[Multiple primary malignancies in patients with head and neck cancer].

From July, 1978 to December, 1985, 1,138 cases of malignancies of the head and neck were treated at the authors' hospital, and up to June, 1986, 132 patients with multiple primary malignancies were detected. In all cases, the incidence rate of a multiple primary malignancy was 11.6%. In 45 (33.0%) of these head and neck cancer cases, the multiple cancer was detected simultaneously, and as for the other cases (66.7%), they were discovered metachronously. In patients with a cancer of the mesopharynx, the incidence rate of a multiple primary malignancy was the highest (25.8%), whereas in those with a cancer of the parotid gland and in those with a cancer of the hypopharynx, the incidence rates were 20.0% and 14.9%, respectively. In most patients the second malignancy occurred in the same head and neck region, and in the rest, the second malignancy was a gastric cancer, a lung cancer, or an esophageal cancer in that descending order. Of the 45 synchronous cancer cases, ten were a thyroid cancer, most being latent. In head and neck malignancies, the authors stress the importance of a precise investigation prior to start of therapy and of maintaining follow-up investigations after therapy.

Adult↗
PubMed1989

[Clinical analysis of supraglottic cancer].

We treated 159 cases of supraglottic cancer including 53 cases of transglottic type from July, 1978 to December, 1984. The mean age was 65 years and man to woman ratio was fifth. Of those patients 15 were classified as T1, 36 as T2, 56 as T3 and 52 as T4 and 113 as N0, 22 as N1, 14 as N2 and 10 as N3. Stage classifications were stage I in 13, stage II in 21, stage III in 50 and stage IV in 75. Treatment modalities were divided radiation in 25, operation only in 105, pre-or post-operative radiation in 29. Multiple primary malignancies were detected in 18 cases (11.3%). Until December, 1986, 52 patients died. Cause of death were original cancer (33 cases, 63.5%), additional malignancies (5 cases, 9.6%), intercurrent disease (12 cases, 23.1%) and others. Deaths of original cancer were attributable to the metastasis to the cervical lymph node and/or distant metastasis, mainly to the lung. Metastatic lymph nodes at the initial treatment were found in 66.7% of patients who died of supraglottic and/or transglottic cancer. In order to improve survival rates, early diagnosis and radical dissection of positive lymph nodes are seemed to be important.

Aged↗
PubMed1989

Presence of pancreatic-type phospholipase A2 mRNA in rat gastric mucosa and lung.

The content of mRNA for a pancreatic-type phospholipase A2 present in rat gastric mucosa was much greater than that in pancreas. In lung the mRNA for this pancreatic-type phospholipase A2 was also detected, but less than in pancreas. Nucleotide sequence analysis showed that these pancreatic-type phospholipase A2 cDNAs derived from rat gastric mucosa and lung were completely identical to that from rat pancreas (Ohara et al. (1986) J. Biochem. 99, 733-739). This demonstrates that the pancreatic-type phospholipase A2 present in gastric mucosa and lung does not originate from pancreas.

Animals↗
PubMed1989

[Local control after radiation therapy for T1N0M0 glottic carcinoma].

From 1978 through 1984, we had 151 patients with T1N0M0 glottic carcinoma. They were treated by radiotherapy with 4MV x-ray in parallel opposing field of 5 X 5 cm2 or 6 X 6 cm2. The total dose was 60 Gy/30 fractions/6 weeks. The local control rate was 88.1%, the local recurrence being noted in 18 cases (11.9%). Of these 18 cases, 6 underwent partial laryngectomy, and 10 total laryngectomy. The remaining two cases died: one refused further treatment for recurrence and the other died in spite of total laryngectomy due to recurrence after partial laryngectomy. The salvage rate was 94.1%. The cumulative survival rate was 82.6% in Tla, 71.5% in Tlb and 81.1% in 151 T1N0. The tumor response was poor in the presence of lesion occupying the whole length of the vocal cord. Also, in the cases with ulcer formation or thickened vocal cord as seen on laryngogram, local control rate was not good. Better results will be achieved by improving treatment techniques, specially by improving dose-distribution by wedge-filtered technique and method for immobilization in plastic shell during radio-therapy.

Adult↗
PubMed1989

Nucleophilic aminoalcohol-catalyzed degradation of indomethacin in aqueous solution.

The catalytic effect of ethanolamine and related aminoalcohols on the rate of degradation of indomethacin in alkaline solutions has been shown to be due to a nucleophilic reaction mechanism involving formation of an intermediate ester consisting of p-chlorobenzoic acid and aminoalcohol through the reaction of aminoalcohol hydroxyl group with carbonyl carbon of indomethacin amide group. This ester subsequently undergoes a rapid intramolecular aminolysis to yield a stable p-chlorobenzamide derivative and/or is hydrolyzed to p-chlorobenzoic acid, depending on the chemical structure of aminoalcohols. No catalytic effect was observed with the amines not containing a hydroxyl group.

Amino Alcohols↗