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Biomedical subjects

S Taniguchi

Publications and source records attributed to S Taniguchi.

At least 415 records · Page 23Linked to original sources

[Aortic valve replacement and coronary artery bypass grafting in a patient with a porcelain aorta due to aortitis syndrome].

Clamping a calcified aorta during cardiac operation increases the risk of cerebral embolism by aortic debris. We operated upon a 61-year-old female with severe angina pectoris due to aortic regurgitation and bilateral coronary calcific ostial stenosis associated with porcelain aorta secondary to aortitis syndrome. At operation, cardiopulmonary bypass was begun with profound hypothermia. Using an occlusion balloon catheter inflated in the ascending aorta, the calcified aorta was incised with scissors. However accidentally the balloon was ruptured by intimal calcification of the ascending aorta, and cardiopulmonary bypass was discontinued for 11 minutes under 20 degrees C hypothermia. Extensive removal of the intimal calcification of the ascending aorta was performed with care and then, the aorta was clamped. Aortic valve replacement and triple coronary bypass operation (SVG to LAD, SVG to LCX, GEA to RCA) were performed. The proximal anastomoses of the SVGs were made on the decalcified aortic wall. The postoperative course was uneventful and aortography revealed neither dissection nor dilatation of the ascending aorta following extensive decalcification procedure of the ascending aorta, and the 3 grafts were all patent. From the experience, we learned that extensive removal of calcification of the aorta can be successfully performed in porcelain aorta due to aortitis syndrome. For CABG in aortitis syndrome, the use of ITA is rarely possible, but the GEA may be a versatile graft.

Aorta↗

[Cell viability assessment of cold-preserved (4 degrees C) and cryopreserved (-196 degrees C) allograft valves by flowcytometric analysis].

We introduced cryopreservation technique to store the allograft valve and subsequently commenced the use of the cryopreserved aortic allograft valve for aortic valve replacement. For the clinical use of the allograft valve, it is essential to evaluate the cell viability. We assessed cell viability of the allograft valve by flowcytometry (FCM), using a fluorescein diacetate (FDA)-propidium iodide (PI) stain. Pulmonary allograft valves were harvested from the cadavers with a consent. Of the 9 valves collected and sterilized in 4 degrees C antibiotic solution for 48 hours, 4 valves were stored under refrigeration (cold-preserved), and the remaining 5 valves were cryopreserved. The warm ischemic time from cardiac death to valve preservation was 7.3 +/- 5.4 hours. The cold-preserved valves were stored at 4 degrees C in the nutrient medium (TC-199, calf serum and HEPES buffer). The cryopreserved valves were frozen by a programmable freezer to -80 degrees C in the same nutrient medium containing 10% dimethylsulfoxide (DMSO), and subsequently stored in liquid nitrogen (-196 degrees C). We assessed the cell viability of the allograft valve leaflet, before storage and at 2 weeks, 1 month and 2 months after the storage. Suspensions of the valve leaflet fibroblasts were double-stained with FDA (1 micrograms/ml) and PI (1 microgram/ml) for flowcytometric analysis of the viable cells (cells showing a chromatic response to FDA but no response to PI). In the cold-preserved group, percentage of the viable cell was 90.3 +/- 3.6% before storage, 62.0 +/- 3.0% after 1 month of storage, and 50.3 +/- 3.7% after 2 months of storage.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve↗

[Study on the inhibitory effect of oral granisetron against nausea/vomiting induced by cytosine arabinoside containing chemotherapy for tumors in the hematopoietic organs].

We investigated the antiemetic effect, safety and usefulness of granisetron tablet on nausea/vomiting induced by cytosine arabinoside (Ara-C) in the chemotherapy for tumors in the hematopoietic organs. Out of 52 cases with malignant tumors in the hematopoietic organs including acute leukemia, 30 in granisetron group had no antiemetic treatment, were evaluated for the clinical efficacy of granisetron and 22 in control group. Their chemotherapies were combination therapy with Ara-C and daunorubicin (DNR), Ara-C and mitoxantrone (MIT), or Ara-C and etoposide (VP-16). In the trial, the dosage of granisetron tablet was 2 mg once a day, and the drug was given before each chemotherapy for 6 consecutive days. In clinical efficacy the effective rate of granisetron (the percentage of cases in which the trial drug was assessed as "Remarkably effective" or "Effective") was more than 80% on each day of administration. There was no adverse event. As the abnormal laboratory test value, only 1 case tested positive in urine protein, whose causal relation to the trial drug was judged as "Unassessable". Granisetron was judged as "Safe" in 31 out of 32 cases (96.9%). In terms of usefulness, the drug was rated "Extremely useful" or "Useful" in 26 out of 30 cases (86.7%). The above results have shown that granisetron tablet, when administered orally once daily at a dose of 2 mg, has an excellent antiemetic effect, and is a safe and useful drug.

Administration, Oral↗

[The significance of arterial redox potential measurement by Vincent's method in evaluating the hemorrhagic shock state of rabbits].

Previously we suggested that the arterial redox potential (ARp) is one of the most reliable indicators to evaluate the severity and outcome of the acutely-ill patients. In this study we attempted to clarify which redox system, intracellular or extracellular, is mainly represented by redox potentials measured from arterial blood in the hemorrhagic shock state rabbits. The arterial pyruvate/lactate, acetoacetate/beta-hydroxybutyrate and oxidized glutathione/reduced glutathione (GSSG/GSH) ratios were measured in hemorrhagic shock rabbits, and correlations between ARp and each of these factors were analyzed. The best correlation was found between ARp and P/L ratio. This indicates that ARp well reflects the cytosolic redox state, i.e. cytosolic [NAD+]/[NADH], and also [ATP]/[ADP][Pi] theoretically. The ARp is a valuable index in evaluating the shock state and can be easily measured with Vincent's method.

Animals↗

Effect of Ca2+ on the binding of Actinobacillus actinomycetemcomitans leukotoxin and the cytotoxicity to promyelocytic leukemia HL-60 cells.

The effects of Ca2+ on the binding of Actinobacillus actinomycetemcomitans leukotoxin (LT) to LT-susceptible promyelocytic leukemia HL-60 cells and the consequent cytotoxicity were investigated in comparison with those on LT-resistant erythroleukemia K-562 cells. The total amount of LT bound to the HL-60 and K-562 cells, as determined by ELISA using anti-LT rabbit serum, was essentially the same for both cells. The percentage of bound LT decreased in the presence of phosphatidylcholine (PC) was also almost equal for both cells. In contrast, EGTA added in the presence of PC enhanced the decrease of bound LT significantly from HL-60, but not from K-562. By monitoring the fluorescence of Fura-2 and of fluorescein as a measure for the change in intracellular calcium ions ([Ca2+]i) and cytotoxic activity, respectively, we showed that the exposure of HL-60 to LT induced the [Ca2+]i increase followed by the cell death, whereas this was distinctly not the case for K-562. These results indicate that a Ca(2+)-dependent LT-binding mechanism is possibly the step characteristic to LT-susceptible HL-60 cells.

Aggregatibacter actinomycetemcomitans↗

[Late results of aortic valve plasty (aortic leaflet slicing) simultaneously performed with mitral valve surgery].

We followed the course of 20 patients who underwent aortic valve plasty (AVP) combined with mitral valve surgery for rheumatic mild aortic valve disease in association with severe mitral valve disease. At operation, all patients underwent aortic leaflet slicing with a knife, and aortic commissurotomy were performed additionally in 10 patients. After surgery, the degree of aortic valve regurgitation and the amplitude of aortic leaflet motion were assessed chronologically, using ultrasound cardiography. One month after surgery, all but one patients showed a reduction in regurgitation to degree I or less. From the third post-operative year, however aortic valve regurgitation tended to increase again. However, the post-operative degree of regurgitation was observed not to be severer than the pre-operative degree of regurgitation, and no patients showed aggravation of aortic valve regurgitation attributable to exacerbation of mitral valve disease. We divided the patients into two groups according to improvement of aortic valve regurgitation. In the group where the degree of regurgitation returned to the pre-operative one, the degree of amplitude of leaflet motion began to reduce from the third post-operative year and was nearly equal to the pre-operative one at the fifth post-operative year. The results of this study can be summarized as follows: 1. From the third post-operative year, aortic regurgitation was aggravated and aortic valve motion amplitude decreased. 2. The number of sliced valve leaflets and incised commissures did not correlate well with the post-operative reduction in regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Separation of hematopoietic stem cells into two populations and their characterization.

Two populations of hematopoietic stem cells (HSC) in mouse bone marrow (BM) are defined on the basis of the presence or absence of interleukin-3 (IL-3) receptor-associated antigen (IL-3RAA). HSC were purified by depletion of mature lymphoid-lineage cells followed by collection of the low-density fraction and sorting of wheat germ agglutinin-binding (WGA+) cells using a fluorescein-activated cell sorter. WGA+ cells were further separated into two populations (IL-3RAA+/WGA+ and IL-3RAA-/WGA+) by a monoclonal antibody (MoAb) against IL-3RAA. IL-3RAA+/WGA+ cells formed CFU-S on day 8; this population consisted mainly of cells in the cycling phase. IL-3RAA-/WGA+ cells form CFU-S on day 12; this population consisted mainly of dormant cells (cells in the G0 phase). When two populations obtained from C3H/HeN mice were injected into lethally irradiated (C57BL/6 x C3H/HeN)F1 mice, donor-derived cells in the peripheral blood (PB) appeared significantly earlier in mice injected with IL-3RAA+/WGA+ cells than in those injected with IL-3RAA-/WGA+ cells, whereas the reconstruction efficiency of IL-3RAA-/WGA+ cells had overtaken that of IL-3RAA+/WGA+ cells 6 weeks after injection. Long-term observation showed no significant difference between these two populations, however. The radioprotective ability (RPA) (30-day survival) of these two populations was therefore compared. The RPA of IL-3RAA-/WGA+ cells was significantly higher than that of IL-3RAA+/WGA+ cells. These findings therefore suggest that the former population is more primitive.

Animals↗

Expression pattern of the activin receptor type IIA gene during differentiation of chick neural tissues, muscle and skin.

To elucidate target cells of activins during embryogenesis we isolated cDNAs of chick activin receptor type II (cActR-II) and studied expression patterns of the cActR-II gene by in situ hybridization. Transcripts of cActR-II were observed in neuroectoderm developing to spinal cord, brain and eyes, in surface ectoderm differentiating to epidermis, and in myotomes differentiating to muscles. The expression patterns of cActR-II suggest that activin and its receptor are involved in differentiation of chick neural tissues, muscle and skin after inducing the dorsal mesoderm.

Activin Receptors↗

Differential expression of two msh-related homeobox genes Chox-7 and Chox-8 during chick limb development.

We have isolated two closely related cDNAs, Chox-7 and Chox-8, encoding homeodomain-containing proteins homologous to Drosophila msh. The Chox-7 and Chox-8 genes are chicken cognates of mouse Hox-7.1 and Hox-8.1, respectively. In situ hybridization using 3' regions of the cDNAs as probes revealed that the Chox-7 gene is highly expressed in the mesenchyme subjacent to the apical ectodermal ridge whereas Chox-8 expression is localized in the anterodistal mesenchymal region at early stages of limb formation, suggesting different roles during limb development. At later stages, both genes are expressed in the anterior and posterior mesenchymes and in the interdigital mesenchyme where programmed cell death occurs.

Amino Acid Sequence↗

Expression of the c-fos oncogene in chemically-induced mouse tumours and in human skin tumours.

Using a polyclonal antibody to fos oncoprotein and an immunofluorescent technique, we investigated expression of the fos oncogene in chemically-induced mouse tumours and human premalignant and malignant skin lesion. In the chemically induced tumours, the nuclei of almost all carcinoma cells stained uniformly with this antibody, while positive cells were observed in the outermost layers in the benign papillomas. In human tumours, a greater degree of nuclear staining was observed in cases of squamous cell carcinoma than in tissues from patients with Bowen's disease. Basal cell carcinoma and malignant melanoma with histological evidence of invasiveness of the tumour cells showed a higher expression of the fos gene product than that seen in histologically circumscribed tumour nests. Thus, a higher expression of the fos oncogene is closely related to the malignant progression of tumour cells, in particular, the extent of invasiveness.

Animals↗

Correlation between spontaneous metastatic potential and type I collagenolytic activity in a human pancreatic cancer cell line (SUIT-2) and sublines.

A human pancreatic cancer cell line (SUIT-2) and four sublines cloned in vitro (S2-007, S2-013, S2-020 and S2-028) were inoculated into nude mice for assessment of metastatic potentials. After 16 weeks of subcutaneous injection, the parent SUIT-2 line metastasized to the lungs and lymph nodes in three of six mice. S2-007 cells presented the highest metastatic potential in pulmonary (5/6) and lymph node (2/6) metastases among the four sublines. No metastasis was found in S2-028. The incidence of spontaneous pulmonary metastasis was correlated with that of pulmonary colonization after intravenous (i.v.) injection of cell clusters (r = 0.87, P = 0.056). Pulmonary colonization potential using single cells, however, did not always reflect a spontaneous metastatic ability. Type I collagenolytic activity in serum-free conditioned media of these cells was correlated effectively with the incidence of spontaneous pulmonary metastasis (r = 0.92, P = 0.026) and pulmonary colonization after i.v. injection of cell clusters (r = 0.95, P = 0.013). Thus, type I collagenolytic activity may possibly be essential to spontaneous cancer metastasis.

Animals↗

Internal thoracic artery grafting for congenital coronary malformations.

We report 2 patients with congenital coronary anomalies (atresia of left main coronary artery and anomalous origin of the left coronary artery from the pulmonary artery) successfully treated with single or double internal thoracic artery grafting. Because the internal thoracic artery has a potential for circumferential as well as longitudinal development, and because of the uncertainty of ultimate vein graft function, we believe that the internal thoracic artery is the best graft material for the treatment of congenital coronary malformations requiring bypass operation in children, adolescents, or even in adults.

Child↗

Production of a negative regulator of IL-3 by bone marrow cells in response to the supernatant of IL-3-producing STIL-3 leukemia cells.

When spleen cells of mice grafted with STIL-3 C5 cells, a leukemic T-cell line producing IL-3, are cultured in vitro, a high IL-3 activity is detectable in the culture supernatant. However, when bone marrow cells of the same grafted mice are cultured under similar conditions, hardly any IL-3 activity is detectable. To elucidate the mechanism of this difference, we examined whether the bone marrow cells either suppress IL-3 production by STIL-3 C5 cells or produce an IL-3 inhibitor. When STIL-3 C5 cells were cultured in the presence of normal bone marrow cells, the culture supernatant showed a significantly reduced IL-3 activity as assessed by growth stimulatory effects on IL-3-dependent DA-1 cells and mast cells. The conditioned medium (CM) did not inhibit the growth of IL-3-independent cell lines. Heat treatment of the CM resulted in a recovery of the IL-3 activity, indicating that the effect was mediated by a heat-labile inhibitor rather than by suppression of IL-3 production. CM of bone marrow cells alone did not inhibit the IL-3 activity. The inhibitor was produced by a stem cell-enriched fraction of the bone marrow, and not by fractions of T cells, granulocytes, or adherent cells including macrophages. Stimulation of the stem cell-enriched fraction of bone marrow with STIL-3 C5-CM also induced the production of the IL-3 inhibitor, which was recovered in a MW 50-100 kD fraction after ultrafiltration. These results suggest a possible presence of a feedback mechanism against the IL-3 effect on hemopoietic stem cells and progenitors in the bone marrow.

Animals↗

Effects of hormonal supplements on the maintenance of cardiac function in potential donor patients after cerebral death.

It is well-known that cardiac function in cerebrally dead patients rapidly deteriorates, leaving the organ unfit for donation. This study investigated whether or not cardiac function in patients with cerebral death can be maintained in a desirable condition with hormonal supplementation. In studies of changes in hormones before and after cerebral death, insulin, glucagon, triiodothyronine, thyroxine, cortisol, vasopressin, epinephrine, and norepinephrine values were measured with a lapse of time after cerebral death. Among them, triiodothyronine and cortisol levels were markedly reduced after cerebral death; therefore, these two hormones were selected as hormonal supplements. The average period from the judgment of cerebral death to cardiac arrest was 4.3 days in 12 patients with no hormonal supplement (group I) and more than 11.5 days in 4 patients with hormonal supplement (group II). This period for patients in group II was significantly longer (p less than 0.05). In 2 of the group II patients the hormonal supplementation was discontinued at the family's request, and in the other 2 patients, it was discontinued because of proposed renal donation. Hemodynamic comparisons between the two groups showed that the mean arterial pressure and the left ventricular maximum dp/dt were significantly higher (p less than 0.01) as was the cardiac index (p less than 0.05) on the 3rd day after cerebral death in members of group II. Thereafter, in group II, an excellent hemodynamic state was maintained until hormonal supplements were discontinued. We conclude that the triiodothyronine and cortisol supplements were effective in the maintenance of cardiac function in patients after cerebral death.

Adolescent↗

Cadherin-mediated cell-cell adhesion is perturbed by v-src tyrosine phosphorylation in metastatic fibroblasts.

Rat 3Y1 cells acquire metastatic potential when transformed with v-src, and this potential is enhanced by double transformation with v-src and v-fos (Taniguchi, S., T. Kawano, T. Mitsudomi, G. Kimura, and T. Baba. 1986. Jpn. J. Cancer Res. 77:1193-1197). We compared the activity of cadherin cell adhesion molecules of normal 3Y1 cells with that of v-src transformed (SR3Y1) and v-src and v-fos double transformed (fosSR3Y1) 3Y1 cells. These cells expressed similar amounts of P-cadherin, and showed similar rates of cadherin-mediated aggregation under suspended conditions. However, the aggregates or colonies of these cells were morphologically distinct. Normal 3Y1 cells formed compacted aggregates in which cells are firmly connected with each other, whereas the transformed cells were more loosely associated, and could freely migrate out of the colonies. Overexpression of exogenous E-cadherin in these transformed cells had no significant effect on their adhesive properties. We then found that herbimycin A, a tyrosine kinase inhibitor, induced tighter cell-cell associations in the aggregates of the transformed cells. In contrast, vanadate, a tyrosine phosphatase inhibitor, inhibited the cadherin-mediated aggregation of SR3Y1 and fosSR3Y1 cells but had little effect on that of normal 3Y1 cells. These results suggest that v-src-mediated tyrosine phosphorylation perturbs cadherin function directly or indirectly, and the inhibition of tyrosine phosphorylation restores cadherin action to the normal state. We next studied tyrosine phosphorylation on cadherins and the cadherin-associated proteins, catenins. While similar amounts of catenins were expressed in all of these cells, the 98-kD catenin was strongly tyrosine phosphorylated only in SR3Y1 and fosSR3Y1 cells. Cadherins were also weakly tyrosine phosphorylated only in the transformed cells. The tyrosine phosphorylation of these proteins was enhanced by vanadate, and inhibited by herbimycin A. Thus, the tyrosine phosphorylation of the cadherin-catenin system itself might affect its function, causing instable cell-cell adhesion.

Animals↗

Relationship of tumor cell motility and morphologic patterns. Part 2. Analysis of tumor cell sublines with different motility in vitro.

We have previously demonstrated by computer simulation that the relationship of proliferation and motility is likely to influence the morphological pattern of a tumor. Our study of a set of melanocytic skin tumors provided evidence that the assumptions of the model were correct with respect to proliferation. In order to test the validity of the assumptions concerning motility, we injected a tumor cell line with low motility in vitro and a subline of the same tumor cell line with high motility in vitro into the thigh of syngeneic rats. When we evaluated the morphological patterns of the resulting tumors by image analysis and compared them with computer simulations, we found that the differences of the morphological patterns were the same as predicted by the computer model. This finding further supports the concept that estimates of tumor cell proliferation and motility can be derived from the analysis of static histological patterns.

Animals↗

Effects of butylated hydroxyanisole on ornithine decarboxylase activity induced by ultraviolet-B and PUVA in mouse skin.

The effects of butylated hydroxyanisole (BHA), a representative phenolic antioxidant, on the activity of ornithine decarboxylase (ODC, an indicator of tumor promotion and epidermal hyperproliferation) induced by ultraviolet-B (UVB) or PUVA in mouse skin were investigated. By topical application of BHA (55 mumol), PUVA-induced ODC activity was suppressed by about 60% at both 12 h and 24 h after treatment. In contrast, BHA failed to suppress UVB-induced ODC activity in mouse skin. These results suggest that the induction of ODC activity by UVB or PUVA is mediated by different pathways.

Animals↗