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Biomedical subjects

H Suda

Publications and source records attributed to H Suda.

At least 181 records · Page 10Linked to original sources
PubMed1993

Reduced cytotoxicity of a root canal sealer through eugenol substitution.

The cytotoxicity of two zinc oxide root canal sealers was investigated in vitro. The sealers were freshly mixed and set for 24 and 168 h. The sealers had identical powders but different liquid components. One (Canals) used eugenol, while the other (Canals-N) used fatty acids. L929 cells were incubated for 4 and 24 h in direct contact with the materials or with an eluate of the materials. The toxicity was evaluated using the radiochromium release assay. In the direct exposure assay, both sealers were cytotoxic when freshly prepared or after 24 h of setting. After 1 wk of setting, Canals was still toxic, while Canals-N was not significantly different from the control in the 4-h assay. In the elution assay the materials showed very low cytotoxicity. Only the eluate from freshly prepared Canals was clearly cytotoxic after 24 h. The liquid of Canals-N was clearly less cytotoxic than liquid from Canals. The results showed that the cytotoxicity of a root canal sealer can be reduced by replacing eugenol with fatty acids.

Animals↗
PubMed1993

ED-110, a novel indolocarbazole, prevents the growth of experimental tumors in mice.

A new indolocarbazole compound, ED-110, which was obtained by glucosylating a microbial product (BE-13793C) and is a potent topoisomerase I inhibitor, showed characteristic inhibitory effects on the growth of 12 human tumor cell lines tested. The IC50 values of ED-110 against 9 of the 12 lines ranged from 11.5 micrograms/ml to 0.07 microgram/ml, while the remaining 3 lines were quite resistant (IC50, > 100 micrograms/ml). In in vivo experiments, i.p. treatment with ED-110 increased the survival period by more than two-fold in mice implanted i.p. with P388, L1210, L5178Y or EL4 murine leukemic cells. The minimum effective dose increasing the life-span of mice bearing P388 leukemia by 25% was < 2.5 mg/kg/day x 10 and the maximum tolerated dose was > 160 mg/kg/day x 10. ED-110 was also effective against the spontaneous metastasis of mouse Meth A fibrosarcoma cells and the growth of xenografted MKN-45 human stomach cancer cells as well as s.c. implanted mouse colon 26 and IMC carcinoma cells. These results indicated that ED-110 may have potential as a new antineoplastic agent with a large chemotherapeutic index and a wide range of effective doses.

Animals↗
PubMed1993

Usefulness of a new perchloric acid treatment method to measure endotoxin in cerebrospinal fluid by the limulus test.

The modernized limulus lysate assay on cerebrospinal fluid pretreated by the new perchloric acid (PCA) treatment was evaluated in one patient with Escherichia coli meningitis and four non-meningitis patients. The endotoxin (ET) concentration was much higher by the new PCA treatment than by the ordinary dilution method in the exacerbation phase of E. coli meningitis. The recovery rate of added ET also demonstrated the superiority of the new PCA treatment.

Colorimetry↗
PubMed1993

[Effects of NC-1100, a calcium channel blocker, on experimental cerebral ischemia/anoxia in rodents].

The anti-ischemic and anoxic effects of NC-1100, a piperazine type calcium channel blocker, were investigated in various cerebral ischemia and anoxia models in mice, gerbils and guinea pigs. Minimal effective doses of NC-1100 were 8 mg/kg, i.p. and 30 mg/kg, p.o. for KCN-induced anoxia; 16 mg/kg, i.p. for decapitation-induced gasping; 30 mg/kg, i.p. for cerebral ischemia induced by occlusion of bilateral carotid arteries in gerbils; and 10 microM for the in vitro ischemic model in hippocampal slices. Moreover, NC-1100 attenuated the disturbance of cerebral energy metabolism induced by decapitation in mice. These results suggest that NC-1100 has a cerebral protective effect, and that attributable to its ability to improve the cerebral energy metabolism disturbance.

Animals↗
PubMed1993

Delayed-type skin allergic reaction in guinea pigs induced by anti-rheumatic compounds with sulfhydryl groups.

Delayed-type skin allergic (DTA) reactions induced by various sulfhydryl compounds were investigated. Sulfhydryl compounds investigated were bucillamine and D-penicillamine: antirheumatic agents, SA981: an intramolecular cyclic disulfide of bucillamine, tiopronin: a hepatoprotective and potent antirheumatic agent and captopril: antihypertensive and potent antirheumatic agent. Guinea pigs were sensitized on day 1 by subcutaneous injection and day 7 by subcutaneous and intramuscular injection of emulsions of these compounds (3 mg/animal) with Freund's complete adjuvant. Two weeks after the second sensitization, 0.3 mg/animal of each compound was intradermally challenged and the 24 hr DTA reaction was evaluated. A large number of sulfhydril compounds showed positive in the DTA reactions and the intensity of these reactions had a good correlation with the frequency of the skin rashes referred to by the adverse effects in clinical reports of anti-rheumatic drugs. It is suggested that guinea pig DTA reaction may provide a good screening way to find new sulfhydryl or disulfide compounds with low incidence of skin rash. A novel sulfhydryl compound N-(2,2-dimethyl-3-mercaptopropionyl)-L-cysteine (SA3441) and its intramolecular cyclic disulfide (4R)-hexahydro-7,7-dimethyl-6-oxo-1,2,5-dithiazocine-4-carboxylic acid (SA3443), which show no DTA activity in guinea pigs, were found using the above-mentioned DTA reaction.

Animals↗
PubMed1993

[Cytotoxicity of anaerobic bacteria isolated from infected root canal].

Bacteria in the infected root canal play an important role in the progression of the periapical lesion. The purpose of the present study was to investigate the cytotoxic effects of bacteria isolated from an infected root canal on the periapical lesion. Four obligately anaerobic bacteria were isolated and their sonic extracts (SE) were prepared. The cytotoxic assay of each SE for MC3T3-E1 cell was used with respect to the morphological cell changes and [3H]-thymidine uptake. The following results were obtained: 1. Four obligately anaerobic bacteria were identified as follows: Porphyromonas asaccharolytica (P. a.), Fusobacterium nucleatum (F. n.), Eubacterium lentum (E. l.), and Peptostreptococcus micros (P. m.). 2. The protein concentrations which induced the morphological cell changes differed in each SE. The SE from P. m. caused cell abnormalities at 10 micrograms protein/ml, F. n. and E. l., at 30 micrograms protein/ml, and P. a., at 100 micrograms protein/ml. 3. The inhibition of the incorporation of [3H]-thymidine into DNA was concentration-dependent. The SE of P. a. showed less cytotoxicity than the others at lower concentrations; 3, 10, 30 micrograms protein/ml. The SE from F. n. had more cytotoxicity at higher concentrations; 100, 300 micrograms protein/ml. These results suggest that these bacterial sonic extracts have a potential to cause morphological cell changes and inhibit the cell proliferation in different concentrations.

Adult↗
PubMed1993

A new antitumor substance, BE-18591, produced by a streptomycete. I. Fermentation, isolation, physico-chemical and biological properties.

New antitumor substance, designated BE-18591, was isolated from the culture broth of a streptomycete, strain BA18591. The active principle was extracted from mycelium by methanol and purified by silica gel chromatography. BE-18591 inhibited the growth of MKN-45 human stomach cancer cell line as well as P388 cell line. In in vivo experiments, BE-18591 inhibited the growth of Ehrlich ascites tumor.BE-18591 showed antimicrobial activity against Gram-positive and some Gram-negative bacteria.

Animals↗
PubMed1993

[Emergency surgical salvage for a closing aortic dissection: 2 case reports].

We report here the emergency surgical salvage for closing an aortic dissection in 2 female patients (case 1; 52 years old, case 2; 72 year old). They were admitted to our clinic for severe back pain (case 1) and a loss of consciousness (case 2). Acute aortic dissection (Stanford A type) with cardiac tamponade was confirmed by chest CT, aortography, and cardiac ultrasonography. Diagnosis was determined as a closing aortic dissection from a thrombosed pseudolumen on enhanced chest CT. An emergency operation was performed on the ascending aorta replacement and included resection of the entry port. The postoperative courses were uneventful, except for temporary hemodialysis in case 1. A closing aortic dissection is a new subcategory for an acute aortic dissection. Diagnosis is difficult, but it is regarded as having a good prognosis following timely emergency treatment. However, provided there is no complication, we recommend that surgical treatment should be performed aggressively to avoid rupture and/or cardiac tamponade.

Aged↗
PubMed1993

[Emergency coronary artery bypass grafting in a chronic hemodialysis patient: a case report].

Emergency coronary artery bypass grafting (CABG) was performed on a 48-year-old male with a long-term hemodialysis history. Following the operation, the patient developed acute elevation of potassium. We applied hemodialysis and obtained beneficial beneficial results. No remarkable change on hemodynamics and coagulant system was observed. Hemodialysis should be recommended on an acute phase for the patients of good cardiac function with less bleeding during the operation.

Angina, Unstable↗
PubMed1993

[Quadricuspid aortic valve: a case report and the review of the literature].

We report a case of rare congenital anomaly of quadricuspid aortic valve and coexisting right coronary displacement. A 70-year-old man was admitted to our hospital for heart murmur and ECG abnormality. The trans-esophageal echocardiography and aortography showed moderate aortic stenosis and regurgitation. At the operation, a quadricuspid aortic valve with three equal cusps and one smaller cusp that showed marked calcification and displacement of right coronary orifice were noted. Successful aortic valve replacement and coronary artery bypass grafting were performed and postoperative course was uneventful.

Aged↗
PubMed1993

[A case of acute postinfarction mitral regurgitation and cardiogenic shock caused by a total rupture of the papillary muscle].

We report a case of mitral regurgitation caused by a total rupture of the posterior papillary muscle that had occurred after acute myocardial infarction. A 72-year-old woman was transferred to our hospital for cardiogenic shock. Echocardiogram revealed massive mitral regurgitation and prolapse of posterior mitral leaflet presumably due to a rupture of a papillary muscle. Cardiac catheterization demonstrated a total occlusion in the segment 2 of the right coronary artery. She had developed progressively increasing heart failure even though the patient had received a successful PTCA for a total occlusion of the right coronary artery. She underwent an emergency mitral valve replacement with preservation of the posterior leaflet using a SJM prosthetic valve. Intraoperative findings were confirmative of total rupture of the posterior papillary muscle. A postoperative course was uneventful. This case is the seventh case which has been reported as the successful operation of a total rupture of the papillary muscle in Japan.

Aged↗
PubMed1992

[2D time of flight stereoscopic MR angiography of pulmonary vessels].

Two-dimensional (2D) time-of-flight (TOF) stereoscopic MR angiographies (MRA) of the pulmonary vessels were obtained from 15 healthy volunteers and five patients with pulmonary cancer in the mediastinum and pulmonary hilum. Fifteen healthy volunteers were examined using FLASH (Fast Low Angle Shot) with breath holding (40/8/40, TR/TE/flip angle). Except for the left superior pulmonary vein, pulmonary vessels in the mediastinum and hilum were well defined on stereoscopic MRA images. Although it was difficult to define the pulmonary arteries in the peripheral zone, intersegmental veins were easily defined with this method. In five cases of pulmonary cancer that were confirmed to show definite tumor involvement of the pulmonary vessels in the mediastinum and hilum by enhanced CT and MRI (SE method), irregular narrowing and interruption of the vessels were shown on MRA. In conclusion, 2D TOF stereoscopic MRA is considered a noninvasive, effective method for evaluation of the morphology of pulmonary vessels adjacent to the tumor in the mediastinum and hilum.

Adenocarcinoma↗
PubMed1992

[Detection of intrahepatic lipids by 1H-MRS--studies by breath-holding & 1 cm3 VOI].

The authors performed 1H-MR spectroscopy (MRS) to depict lipids in the liver of 10 healthy volunteers. Spectra were obtained by a 1.5 T-MR unit, with STEAM from 1 x 1 x 1 cm3 VOI. Lipid peaks were depicted in 7 of the 10 volunteers by breath-holding 1H-MRS study, while in only 4 on normal breathing. The existence of lipids could not be depicted through chemical shift imaging adopting in-phase & opposed images. This suggests a clinical utility of 1H-MRS, particularly through breath-holding studies, in depicting lipids from 1 x 1 x 1 cm3 VOI in the liver in vivo.

Humans↗
PubMed1992

Effects of a newly synthesized leukotriene antagonist, NZ-107, on immediate-type hypersensitivity reaction in rats and guinea-pigs.

The effects of 4-bromo-5-(3-ethoxy-4-methoxybenzylamino)-3(2H)-pyridazinone (NZ-107) on immediate type hypersensitivity reactions in rats and guinea-pigs were studied. 1. When NZ-107, at a dose of 50 mg/kg (i.p.) or 100 mg/kg (orally), was administered to rats, 48-h homologous passive cutaneous anaphylaxis (PCA) reaction and histamine-, leukotriene C4 (LTC4)- and leukotriene D4 (LTD4)-induced skin reactions were suppressed by the agent. 2. NZ-107 (10(-6) g/ml) inhibited both LTC4- and LTD4-induced contractions of isolated rat stomach smooth muscle. 3. NZ-107 inhibited antigen-induced histamine release from rat peritoneal mast cells by 26% at a concentration of 10(-4) g/ml. 4. NZ-107, at doses of 25 and 50 mg/kg (orally), significantly inhibited guinea-pig 3-h heterologous PCA reaction. 5. NZ-107 inhibited antigen-induced histamine release from guinea-pig lung tissue by 17% and 48% at concentrations of 5 x 10(-5) and 10(-4) g/ml, respectively. 6. NZ-107, at doses of 25 and 50 mg/kg (i.p.), inhibited antigen-induced bronchoconstriction and eosinophil accumulation in the bronchoalveolar lavage fluid (BALF) of guinea-pigs. These results suggest that NZ-107 has anti-allergic action including inhibition of eosinophil accumulation in an antigen-challenged airway lesion in rats and guinea-pigs. The anti-allergic action of this agent is thought to be due to its action as a histamine and LT antagonist and its consequent inhibition of antigen-induced histamine release.

Animals↗
PubMed1992

In vitro biological profile of a highly potent novel endothelin (ET) antagonist BQ-123 selective for the ETA receptor.

The novel endothelin (ET) receptor antagonists BE-18257A and BE-18257B were isolated from the fermentation products of Streptomyces misakiensis. The above-mentioned compounds inhibited [125I]ET-1 binding to ETA receptors (selective for ET-1) on porcine aortic vascular smooth muscle cells (VSMCs) with IC50 values of 1.4 and 0.47 microM, respectively. [125I]ET-1 binding to ETB receptors (nonselective to ET isopeptides) in cerebellar membranes was not inhibited by either of these compounds even at 100 microM. The synthesized analogue BQ-123 induced extremely potent inhibition of [125I]ET-1 binding to ETA receptors (IC50 of 7.3 nM), but it barely inhibited [125I]ET-1 binding to ETB receptors (IC50 of 18 microM) and binding of various other peptides to their receptors. BQ-123 shifted the concentration-response curve for ET-1 toward the right in porcine isolated coronary arteries, indicative of competitive antagonism for the ETA receptor. However, there was a small amount of BQ-123-insensitive vasoconstriction that paralleled the incomplete inhibition of [125I]ET-1 binding in the membrane of the vascular smooth muscle layer. These data suggest that the artery contracts via both ETA and ETB receptors and that BQ-123 selectively inhibits ETA-mediated contraction. Furthermore, BQ-123 revealed large tissue and species differences in the distribution of ETA receptors. Thus, the potent ETA antagonist BQ-123 should be useful in clarifying the (patho)physiological roles of ETA receptors.

Amino Acid Sequence↗
PubMed1992

Neonatal adrenal hemorrhage detected antenatally.

This report describes two cases of neonatal adrenal mass detected antenatally by routine ultrasound (US) examination of pregnant women. Case 1 was recognized by the fetal US at 31 weeks gestation. The mass, located near the right upper pole of the kidney, was echolucent on US examination. A serial US of the mass showed changes of the internal echoes from a cystic lesion to a mixed lesion, and finally to a hyperechogenic lesion due to a neonatal adrenal hemorrhage (NAH). At 33 days, laparotomy was performed, and the pathological finding revealed an NAH owing to the mass bleeding into the adrenal cyst. Case 2 was also detected by fetal US just before birth. The mass of the right upper pole of the kidney was hyperechogenic on US examination. The baby clinically deteriorated after birth because of hypovolemia owing to NAH. A serial US of the mass showed the change from a hyperechogenic to a cystic lesion. Four months later, the mass spontaneously resolved. From the US spectrum, the mass was diagnosed as NAH. These are the second known cases of NAH detected before birth in Japan.

Adrenal Gland Diseases↗