Search PubMed⌕ Search

Biomedical subjects

M Kodama

Publications and source records attributed to M Kodama.

At least 433 records · Page 24Linked to original sources
PubMed1988

Actinoplanones A and B, new cytotoxic polycyclic xanthones from Actinoplanes sp.

Two new cytotoxic polycyclic xanthones, actinoplanones A (1) and B (2) were isolated from the culture broth of Actinoplanes sp. R-304 by monitoring their bioactivity against HeLa cells. Compound 1 was extremely cytotoxic (IC50 0.00004 micrograms/ml) against HeLa cells. The structures of 1 and 2 were established mainly by analyses of 2D heteronuclear correlation NMR experiments. The absolute configurations of the asymmetric carbons of the compounds have been assigned to be 9R, 24S, 25R and 27S by circular dichroism spectra and NMR analysis using chiral derivatives (esters of alpha-methoxy-alpha-(trifluoromethyl)acetic acid).

Actinomycetales↗
PubMed1988

Actinoplanones C, D, E, F and G, new cytotoxic polycyclic xanthones from Actinoplanes sp.

Our previous finding of strong cytotoxic polycyclic xanthones, actinoplanones A (1) and B (2), in the culture broth of Actinoplanes sp. R-304 stimulated us to isolate further five new cytotoxic polycyclic xanthones which were named actinoplanones C (3), D (4), E (5), F (6) and G (7) from the broth. Actinoplanones C (3) and G (7) showed very strong cytotoxicity against HeLa cells at less than 0.00004 microgram/ml dosage (IC50). The structures of 3-7 were varieties of 1 for the N-2 and C-4 substituents. All or several actinoplanones showed strong antimicrobial activities against bacteria and the rice blast fungus. Actinoplanone A (1) was tested for cytotoxicity against various tumor cells and for inhibitory effect on HeLa cell macromolecular synthesis, and 1 exhibited strong cytotoxicity against the cells and inhibitory action on DNA synthesis.

Actinomycetales↗
PubMed1988

[Congenital vesical diverticulum in a child].

A case of congenital vesical diverticulum in childhood is reported and 28 other cases in children from the Japanese literature are reviewed. A 9-year-old boy presented with hematuria and two-phase micturition. Excretory urogram and voiding cystourethrogram showed a diverticulum of the bladder on the left side and left vesico-ureteral reflex. Diverticulectomy and left ureteroneocystostomy (by Paquin's method) were performed. Post-surgical recovery was very good. All 28 cases we reviewed were in males whose average age was 6 years and 2 months. Their chief complaints consisted of dysuria, urinary infection and hematuria. The two-phase micturition appeared to be rather rare.

Child↗
PubMed1988

[True hermaphroditism with 46, XX karyotype: report of a case].

A case of true hermaphroditism, in a 4-year-old, legally female, is reported. The external genitalia showed clitorism and labial agglutinate, and her karyotype from peripheral lymphocytoculture was 46,XX. She received gonadectomy at both sides, clitorectomy and plasty of vaginal orifice. Histopathological examination showed that both gonads were ovotestis.

Child, Preschool↗
PubMed1988

[Study on the lymphatic flow of the lower gastric region for radical lymphadenectomy in advanced lower gastric cancer].

A prognosis of patients with a curative resected advanced cancer of the lower gastric region was worse than that of the other region of the stomach. The 5 year survival rate was only 47.3%. One of the main reasons was that a rate of lymph node recurrence was higher. In this point of view, we studied on lymphatic flow of the lower gastric region using an activated carbon particle (CH40). Lymph nodes were stained black soon after the injection of CH40 into the lower gastric wall at laparotomy. The black stained rate of an each regional lymph node was as follows. 3. 58%, 4. 17%, 5. 50%, 6. 25%, 1. 21%, 7. 58%, 8. 83%, 9. 58%, 11. 17% and 12. 33% in case of injection into the greater curvature and and 4. 31%, 6. 100%, 8. 25%, 9. 25%, 14V and 56% in case of injection into the lesser curvature. The stained rate was relatively high in 12 and 14V lymph node which we had not routinely dissected. The rates of lymph nodes stained black were related to those of cancer metastasis. The results suggest that lymphadenectomy of 12 for the cancer at the lesser curvature and that of 14V for the cancer at the greater curvature might make a prognosis of lower gastric cancer better.

Adult↗
PubMed1988

[Clinical effects of terodiline hydrochloride for urinary frequency and sense of residual urine].

The clinical effects of terodiline hydrochloride were evaluated in forty-four patients with urinary frequency and/or sense of residual urine. After a four-week treatment with 24 mg terodiline hydrochloride once daily, subjective symptoms were improved and micturition frequency was decreased significantly. Slight dysuria was reported as a side effect only in one patient. Terodiline hydrochloride is considered to be superiorly effective and safe for the treatment of urinary frequency and sense of residual urine.

Adult↗
PubMed1987

Activation of deoxycholic acid by the lipid peroxy radical and its covalent binding to nucleic acids.

Deoxycholic acid, a colon tumor promoter, was found to bind covalently to DNA and RNA in the presence of methyl linoleate hydroperoxide and ferrous ion. This binding was shown to occur specifically with guanine residues and its covalent nature was demonstrated by analysis of hydrolysates of nucleic acid adducts. These findings are discussed in connection with the increased risk of colon cancer associated with a high fat and meat diet.

DNA↗
PubMed1987

Chemically modified collagen: a natural biomaterial for tissue replacement.

Glutaraldehyde crosslinking of native or reconstituted collagen fibrils and tissues rich in collagen significantly reduces biodegradation. Other aldehydes are less efficient than glutaraldehyde in generating chemically, biologically, and thermally stable crosslinks. Tissues crosslinked with glutaraldehyde retain many of the viscoelastic properties of the native collagen fibrillar network which render them suitable for bioprostheses. Implants of collagenous materials crosslinked with glutaraldehyde are subject long-term to calcification, biodegradation, and low-grade immune reactions. We have attempted to overcome these problems by enhancing crosslinking through bridging of activated carboxyl groups with diamines and using glutaraldehyde to crosslink the epsilon-NH2 groups in collagen and the unreacted amines introduced by aliphatic diamines. This crosslinking reduces tissue degradation and nearly eliminates humoral antibody induction. Covalent binding of diphosphonates, specifically 3-amino-1-hydroxypropane-1, 1-diphosphonic acid (3-APD), and chondroitin sulfate to collagen or to the crosslink-enhanced collagen network reduces its potential for calcification. Platelet aggregation is also reduced by glutaraldehyde crosslinking and nearly eliminated by the covalent binding of chondroitin sulfate to collagen. The cytotoxicity of residual glutaraldehyde--leaching through the interstices of the collagen fibrils or the tissue matrix--and of reactive aldehydes associated with the bound polymeric glutaraldehyde can be minimized by neutralization and thorough rinsing after crosslinking and storage in a nontoxic bacteriostatic solution.

Adenosine Diphosphate↗
PubMed1987

Toxin production in the dinoflagellate Protogonyaulax tamarensis.

Many clones of Protogonyaulax tamarensis were collected from Ofunato Bay in the same season and cultured under the same conditions. The toxicity of the cultured cells of these clones was remarkably different from each other (maximum of 100-fold). Significant differences (maximum of 20-fold) in toxicity of cultured cells were also observed among subclones isolated from a single clonal culture. It is unlikely that this variation in toxicity among subclones is due to mutation during culture. From these observations we suggest that toxin production in P. tamarensis is not a hereditary characteristic.

Animals↗
PubMed1987

Generation of free radical and hydrogen peroxide from 2-hydroxyemodin, a direct-acting mutagen, and DNA strand breaks by active oxygen.

Among several hydroxylated metabolites of emodin, a fungal anthraquinone and constituent of rhubarb, 2-hydroxyemodin was a direct-acting mutagen showing a large electron-spin resonance (ESR) signal in the presence of DNA, especially at alkaline pH. Coupled with generation of free radical, hydrogen peroxide but not superoxide was formed. The active oxygen produced from 2-hydroxyemodin induced strand breaks in phi X 174 replicative form I DNA (supercoiled covalently closed circular duplex DNA). These results suggest a possible role of active oxygen in the process of mutagenesis.

Anthraquinones↗
PubMed1987

Hormonal status of gastric cancer. I. Effect of rice and salty rice diets on the constitution of urinary steroids in mice.

We investigated the effect of rice and salty rice diets on the physical growth and on the constitution of urinary steroids in Swiss/ICR mice. The following three kinds of diets were employed in the feeding experiment: 1) standard diet; 2) rice diet; and 3) salty rice diet. Long-term maintenance of mice on both rice and salty rice diets led to a relative increase of tetrahydrocortisol associated with a concomitant decrease of androgen, progestin, and cholesterol in urine. Evidence was presented to indicate that the activity of endogenous hydrocortisone in mice could be augmented by an increased intake of sodium chloride alone; there was also evidence that the glandular stomach of a young mouse drinking physiological saline is highly sensitive to a suppressive action of hydrocortisone. We concluded that the two experimental diets produced a state of catabolic glucocorticoid excess combined with a deficiency of anabolic androgen and progestin. Mineralocorticoid status was not examined. In the salty rice diet, a markedly lower weight gain was observed, whereas in the rice diet, in general, no significant weight changes were observed.

Animals↗
PubMed1987

Hormonal status of gastric cancer. II. Abnormal constitution of urinary steroids in gastric cancer patients.

We undertook a case-control study regarding the excretions of 14 urinary steroids in gastric cancer (GC) patients. The results are as follows: the levels of androgens, progestins, and two corticosteroids were, relative to tetrahydrocortisol, significantly depressed in GC patients of both sexes compared with the corresponding normal controls. The deviation profile of urinary steroids was not affected by radical gastrectomy. Evidence indicated that observed changes of GC urines were the steroidal expression of a decrease of endogenous testosterone combined with an increase of endogenous hydrocortisone; there was also evidence that the hormonal environment of our GC patients was endocrinologically homologous to that of rice-fed or salty rice-fed mice. Epidemiological inquiry revealed that GC patients having more access to rice-rich or salt-rich diets were taller and less obese than were rural healthy controls. In agreement with the anthropometric data of those cancer patients is the finding that the specific death rate of GC (as calculated for each of 15 prefectures of northern Japan) was positively correlated for each sex with the mean heights, but not with the mean weights, of 14-year-old youths of those areas. This paper discusses the possible relevancy of the hormonal and epidemiological aspects of GC patients to gastrocarcinogenesis in light of steroid physiology.

Adult↗