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Biomedical subjects

M Nishijima

Publications and source records attributed to M Nishijima.

At least 163 records · Page 9Linked to original sources
PubMed1993

Mechanisms of suppression of X-ray-induced transformation of 10T1/2 cells by lipopolysaccharide.

X-ray induced neoplastic transformation of C3H/10T1/2 cells was suppressed equally by Lipid A and LPS. We examined the effects of several modifiers of arachidonic acid (AA) metabolism in our investigation on the suppression mechanism of LPS. Dexamethasone (DM), an inhibitor of phospholipase A2 (PLA2), abolished the effect of LPS, whereas bromophenacyl bromide (BPB), another inhibitor of PLA2 did not. AA and aspirin neither changed the transformation frequency nor blocked the effect of LPS. TPA, 12-O-tetradecanoyl-phorbol-13-acetate, slightly enhanced radiation transformation, which was diminished by LPS. We also examined the effects of these modifiers on the release of radioactivity from 3H-AA-labeled 10T1/2 cells. No definite correlation was found between the change of AA metabolism and suppression of the transformation frequency by LPS. LPS, however, enhanced dose-dependent myristoylation of the 22 and 67 kDa proteins of 10T1/2 cells.

Animals↗
PubMed1993

Synthesis of 2-deoxy-2-[(2R,3S)-2-fluoro-3-hydroxytetradecanamido]- 3-O-[(3R)-3-hydroxytetradecanoyl]-4-O-phosphono-D-glucopyranose and its (2S,3R)-isomer.

2-Deoxy-2-[(2R,3S)-2-fluoro-3-hydroxytetradecanamido]-3-O-[( 3R)-3-hydroxytetradecanoyl]-4-O-phosphono-D-glucopyranose and its (2S,3R)-isomer were respectively synthesized from allyl 2-[(2R,3S)-3-(benzyloxycarbonyloxy)-2-fluorotetradecanamido] -2-deoxy-4,6-O-isopropylidene-beta-D-glucopyranoside and its corresponding (2S,3R)-isomer. Both target compounds did not activate macrophage, but the (2S,3R)-analogue strongly inhibited the binding of LPS to macrophage.

Carbohydrate Sequence↗
PubMed1993

Novel antimycin antibiotics, urauchimycins A and B, produced by marine actinomycete.

Two novel antimycin antibiotics, urauchimycins A and B, were isolated from a fermentation broth of a Streptomyces sp. Ni-80. The strain was isolated from an unidentified sponge. Their chemical structures were determined by 2D NMR analysis. They are the first antimycin antibiotics which possess a branched side chain moiety. They exhibited inhibitory activity against morphological differentiation of Candida albicans.

Animals↗
PubMed1993

[Histological study of the outer membrane of chronic subdural hematoma: possible mechanism for expansion of hematoma cavity].

Relationship between the histological features of the outer membrane of chronic subdural hematoma and computed tomography (CT) findings, and the period from trauma to surgery were studied, and the mechanism of hematoma enlargement was discussed. This study included 43 patients aged 16 to 84 years. The outer membranes collected during operation were examined by hematoxylin and eosin staining and elasticavan Gieson staining. Histological features were classified into 4 types according to maturity and intensity of the inflammatory reaction and hemorrhage. Type I: Noninflammatory membrane. This type of membrane was observed in 3 cases. This membrane, containing immature fibroblasts and collagen fibers, was associated with very slight or sparse cell infiltration and neocapillaries. Type II: Inflammatory membrane. This type of membrane was observed in 21 patients. The type, consisting of one layer of immature connective tissue, was associated with marked cell infiltration and vascularization throughout the entire thickness. Type III: Hemorrhagic-inflammatory membrane. This type of membrane was observed in 14 patients. This type had a structure of 2 or 3 layers, and was associated with capillaries with a large lumen on the side of the dura mater and marked cell infiltration and many thin new vessels on the side of the hematoma cavity. Some patients showed a layer consisting of only collagen fibers and fibroblasts between two such layers. In addition, hemorrhage into the membrane was often observed. Type IV: Scar-inflammatory membrane. This type of membrane was observed in 4 patients. This type showed inflammatory cell infiltration, neovascularization and hemorrhage in the outer membrane of cicatricial tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Sphingolipids are essential for the growth of Chinese hamster ovary cells. Restoration of the growth of a mutant defective in sphingoid base biosynthesis by exogenous sphingolipids.

We previously isolated a temperature-sensitive Chinese hamster ovary cell mutant (strain SPB-1) with thermolabile serine palmitoyltransferase, which is involved in the first step of sphingolipid synthesis (Hanada, K., Nishijima, M., and Akamatsu, Y. (1990) J. Biol. Chem. 265, 22137-22142). In this study, sphingolipid-deficient culture medium was used to examine the effect of exogenous sphingolipids on the cell growth of SPB-1. When cultivated in the sphingolipid-deficient medium, SPB-1 cells ceased growing at non-permissive temperatures. Under these conditions, de novo sphingolipid synthesis ceased in the SPB-1 cells, resulting in a decrease in levels of sphingomyelin and ganglioside sialyl lactosylceramide (GM3), whereas the parental CHO-K1 cells grew logarithmically with normal sphingolipid synthesis. Exogenous sphingosine restored the contents of both sphingomyelin and GM3 in the SPB-1 cells near to the parental levels through metabolic utilization and allowed the mutant cells to grow even at the non-permissive temperature. Similarly, exogenous sphingomyelin restored the sphingomyelin levels and only partly the GM3 levels and also suppressed the temperature-sensitivity of the SPB-1 cell growth. In contrast, exogenous glucosylceramide, which restored the GM3 levels but not the sphingomyelin levels, failed to suppress the temperature sensitivity of the SPB-1 cell growth. Combination of exogenous sphingomyelin with ceramide, glucosylceramide, GM3, or sphingoid bases did not show any synergistic or additive effect on the SPB-1 cell growth enhancement, compared with sphingomyelin alone. The results indicated that the temperature sensitivity of the SPB-1 cell growth was due to the lack of cellular sphingolipids, possibly that of sphingomyelin.

Acyltransferases↗
PubMed1992

Structure of a heteroglycan isolated from the fungus Omphalia lapidescens.

The major, water-soluble polysaccharide isolated from the sclerotia of Omphalia lapidescens, and purified by chromatography on DEAE-Sephadex A-50 and Toyopearl HW-65F, is a heteroglycan (OL-3), [alpha]D20 - 50 degrees (c 1, water), which is composed of D-glucose, 2-acetamido-2-deoxy-D-glucose, and D-glucuronic acid in the molar ratios 1.21:1.00:1.38. Methylation analysis, partial acid hydrolysis, and f.a.b.-m.s. of the hydrolysates indicated OL-3 to have a highly branched structure involving (1----3)-, (1----4)-, (1----6)-, and (1----3,6)-linked, and non-reducing terminal D-glucopyranosyl residues, and also to contain 2 acetamido-2-deoxy-beta-D-glucopyranosyl-(1----4)-beta-D- glucopyranosyluronic acid and beta-D-glucopyranosyl-(1----4)-2-acetamido-2-deoxy-beta-D-glucopyranosyl -(1----4)-beta-D-glucopyranosyluronic acid segments.

Agaricales↗
PubMed1992

Clinical investigation with KTP/YAG laser for lower genital tract disease.

The KTP/YAG laser (Laserscope) was clinically investigated in treatment of 54 patients, 28 of whom had cervical intraepithelial neoplasia (CIN), 11 who had cervical polyp, 4 with cervical myoma, 9 with condyloma acuminata, and 2 with vulvar tumors. All patients were treated on an outpatient basis with local anesthesia. The procedure was performed in contact and noncontact irradiation modes with the tissue by using a bare fiber held in a handpiece with a power setting of 10-15 watts. Laser excisional conization was carried out for the treatment of CIN, laser excision was used for the treatment of condyloma of the cervix, cervical polyp, cervical myoma, and benign tumor of the vulva, and laser vaporization was used for condyloma of the vulva. The first cure rates were all satisfactory for the follow-up periods of 4-10 months. Complications during and post operation were minimal. The KTP laser provided good vaporizing ability compared with CO 2 and YAG lasers. When massive bleeding occurred which could not be stopped with the KTP laser, the YAG laser was used.

Evaluation Studies as Topic↗
PubMed1992

Physicochemical characteristics and antitumor activities of a highly branched fungal (1----3)-beta-D-glucan, OL-2, isolated from Omphalia lapidescens.

Physicochemical properties and antitumor activities of a fungal (1----3)-beta-D-glucan, OL-2, isolated from Leiwan (Omphalia lapidescens) were examined. OL-2 showed sharp signals on carbon-13 nuclear magnetic resonance spectrum in dimethylsulfoxide-d6 as a solvent, and these signals were significantly reduced by the addition of distilled water to the concentration of 20%. This phenomenon is consistent with the general property of the gel forming (1----3)-beta-D-glucan. Binding of OL-2 to Congo red induced a significant change of lambda max to a longer wavelength, and the concentration to induce gel to sol transition was about 0.7 N; in contrast, the concentration was about 0.2 N in the cases of SPG and curdlan. These observations suggested that the gel structure would be significantly stabilized in the case of OL-2. OL-2 showed no or low antitumor activity against the solid form of Sarcoma 180 by intraperitoneal and intralesional administrations; however, it was effective on the ascites form of Sarcoma 180. Of interest, OL-2 also showed significant antitumor activity against the ascites form of MH-134 when administered with 5-fluorouracil. These results indicated that OL-2 showed characteristic features regarding its physicochemical properties and antitumor activity.

Agaricales↗
PubMed1992

Structure and antitumor activity of the less-branched derivatives of an alkali-soluble glucan isolated from Omphalia lapidescens. (Studies on fungal polysaccharide. XXXVIII).

The structure and antitumor activity of Smith-type degradation products (OL-2-I, OL-2-II and OL-2-III) of an alkali-soluble glucan, OL-2, isolated from a crude fungal drug "Leiwan" (Omphalia lapidescens) were investigated. Methylation analysis suggested that OL-2-I was a (1----3)-beta-D-glucan with approximately one branch at every three main chain glucosyl units at each C-6 position; OL-2-II was a (1----3)-beta-D-glucan with approximately one branch at twenty four main chain glucosyl units at each C-6 position (number of all main chain glucosyl units is on average). OL-2-I, OL-2-II and OL-2-III which were Smith-type degradation products of OL-2, showed potent antitumor activity against the solid form of sarcoma 180 in ICR mice. These results indicated that the degree of beta-linked branching at position 6 was remarkably related to the antitumor activity.

Agaricales↗
PubMed1992

[Antimutagenic activities of hexane extracts of the fruit extract and the kernels of Prunus mume Sieb. et Zucc].

Antimutagenic activities of hexane extracts obtained from the fruit extract (UE) and the Kernels (KE) of P. mume were examined. These extracts showed inhibitory activities to known mutagens, 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide, benzo[alpha]pyrene and aflatoxin B1 in the Ames assay using Salmonella typhimurium TA100 and TA98 strains. The UE and KE fractions were then separated by silicic acid column chromatography with a stepwise elution method using ether-hexane. The location of the active substances in the fractions was also determined by thin-layer chromatography. Consequently, it was found that the effective substances for the desmutagenicity were fatty acids, and identified by gas liquid chromatography, mainly as oleic acid, linoleic acid and linolenic acid in UE, and mainly as oleic acid and linoleic acid in KE, respectively.

Antimutagenic Agents↗
PubMed1992

Etiological evaluation of dural arteriovenous malformations of the lateral and sigmoid sinuses based on histopathological examinations.

Controversy persists concerning the pathogenesis of dural arteriovenous malformations (AVM's) and whether they are congenital or acquired. Furthermore, it remains undetermined whether the lesion is located in the sinus itself or within the sinus wall. In order to elucidate the pathogenesis of dural AVM's of the lateral and sigmoid sinuses, histopathological profiles of this disease were studied in serial sections of completely resected lesions from three patients. The essential lesion was histologically confirmed to be a dural arteriovenous fistula within the wall of the venous sinuses. The etiology process of this disease and its progression were evaluated.

Adult↗
PubMed1992

[Malignant melanoma metastatic to the cavernous sinus and skull with an unknown primary origin: report of a case].

A rare case of malignant melanoma metastatic to the cavernous sinus and skull, with an unknown primary origin, is reported. A 46-year-old man noticed diplopia, lt. ptosis and swelling in the parietal and maxillary regions. The parietal skull tumor and the maxillary lymph node were excised and histological examination revealed malignant melanoma. Because of its roentogenological characteristics, the lesion of the cavernous sinus was also thought to be the site of metastasis of malignant melanoma. This case is rare because the initial symptom was cavernous sinus syndrome, and no involvement of brain parenchyma was observed.

Cavernous Sinus↗
PubMed1992

[Comparison of YAG and CO2 laser excisional conization for the treatment of uterine cervical neoplasia].

Thirty-nine patients with cervical neoplasia who were treated by CO2 laser excisional conization were compared with a group of 37 patients whose diagnosis and age were similar were treated by YAG laser excisional conization. Every operation in our series was performed on an outpatient basis. The differences between two groups were statistically significant: The CO2 laser group revealed the advantages in the healing periods from treatment to the end of epithelization (p less than 0.01: T test) and irradiation time (p less than 0.001). There was no difference in the blood loss during the operation. Both initial cure rates were 100% during the follow-up period of 21 to 65 months. During and post operations, more patients required additional measures such as sutures for uncontrollable bleeding in the CO2 laser group. In conclusion, both methods are felt to be good diagnostic and also therapeutic procedures for cervical neoplasia on an outpatient basis.

Female↗
PubMed1992

[Effect of suppletory estrogen or 1,25(OH)D3 on bone mineral content].

Post-menopausal changes in bone mineral content (BMC) and the effect of suppletory estrogen or 1,25(OH)D3 was studied. BMC was evaluated by means of quantitative computed tomography. Post-menopausal BMC (age 45-49) was 158.4 +/- 42.0 mg/cm3 which was significantly lower than in other subjects in the same aged group (192.3 +/- 27.1 mg/cm3). At two years, ten years and more than ten years post-menopause it decreased significantly by 17%, 30%, 55% respectively, compared with that of pre-menopausal BMC. The administration of conjugated estrogen (0.625 mg) or 1,25(OH)D3 was effective in preventing bone loss, although a transient decrease in BMC was observed in some cases to which 1,25(OH)D3 was administered. In cases of pre-menopausal bilateral oophorectomy, BMC was found to decrease significantly to the post-menopausal level about two years after operation. However, long-term estrogen replacement therapy tends to inhibit the decrease.

Aged↗