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Biomedical subjects

I Mori

Publications and source records attributed to I Mori.

At least 145 records · Page 8Linked to original sources
PubMed1989

[The study of polyamine levels and enzyme activities in metabolic pathway of polyamine in spleen of mice inoculated tumor cells].

Polyamine concentrations, ornithine decarboxylase (ODC) activity and S-adenosyl-L-methionine decarboxylase activity in the spleen of ICR mice after s.c. inoculation of 2 X 10(6) Sarcoma-180 ascites tumor cells were studied. ODC activity and putrescine concentration in spleen were markedly elevated at 1 and 5 d after inoculation of tumor cells, and spleen weight increased from 3 to 7 d after the inoculation. The elevations at 5 d after inoculation corresponded to the enlargement of spleen. By s.c. inoculation of 2 X 10(6) METH-A ascites tumor cells into BALB/c mice, ODC activity and putrescine concentration in the spleen were also elevated at about 1 d after inoculation. On the other hand, when normal cells (spleen cells) were inoculated into ICR mice, those variations were not observed. From these facts, it was thought that elevations of ODC activity and putrescine concentration in the spleen at 1 d after inoculation of tumor cells were related to the immune response. Further, those were elevated according to the number of inoculated cells, and when cell membranes of 2 X 10(6) Sarcoma-180 ascites tumor cells were inoculated, those were also elevated at about 1 d after the inoculation. From the above facts, it was proved that elevations of ODC activity and putrescine concentration in the spleen at 1 d after the inoculation of tumor cells were due to antigenicity of tumor cell membranes and those were dependent on the number of inoculated tumor cells.

Adenosylmethionine Decarboxylase↗
PubMed1989

Determination and biokinetics of germanium in mouse tissues by atomic absorption spectrometry with electrothermal atomization.

There are few papers on the analysis of Ge in biomaterials. A highly sensitive method is required for such determination of Ge because its concentration is very low. We developed a sensitive analytical method for determining Ge in biomaterials by using 0.05 mol/l Co (NO3)2 media as a matrix modifier with flameless atomic absorption spectrometry. This method was applied to the determination of Ge in mouse tissues, and the biokinetic parameters of Ge in mouse tissues were evaluated using the data of uptake and retention after a single peroral administration of GeO2 solution. Ge was not detectable in the blood or tissues of normal mice. The uptake of Ge into kidney is much larger than that into other tissues after injection of GeO2 solution. The disappearance of Ge from blood and the tissues is very fast. It could hardly be detected in any of the tissues 24 h after injection. The biological half-life of Ge in brain is 6.3 h, but in other tissues--1.2 h (in blood) to 4.5 h (in pancreas)--it is shorter than in brain. By the fact that Ge is rapidly excreted from all tissues, it can be understood that Ge is not detected in normal mouse tissues and its toxicity is weaker than that of other metals.

Animals↗
PubMed1988

Impaired arginine-vasopressin secretion associated with hypoangiotensinemia in hypernatremic dehydrated elderly patients.

Nine elderly patients, some with preceding dementia, presented with adipsia, progressive dehydration, impaired consciousness, and hypernatremia following common acute infections without gastrointestinal disturbance. Studies before rehydration revealed inappropriately low plasma arginine-vasopressin (AVP) levels for plasma osmolality, insufficiently concentrated urine, absolutely or relatively low plasma angiotensin II (A-II) concentrations (compared with plasma renin activity and plasma angiotensin I concentrations), and low serum angiotensin I-converting enzyme activities. The plasma AVP concentrations were positively correlated with the plasma A-II concentrations (r = .677) but not with plasma osmolality. The plasma AVP level was raised by an intravenous infusion of A-II in one patient. These findings suggest the following sequence of events: impaired A-II production caused impairment of thirst perception, renal-concentrating capacity, and AVP secretion and contributed to development of hypernatremic dehydration in these elderly patients.

Aged↗
PubMed1988

Analysis by high-performance gel permeation chromatography of hyaluronic acid in animal skins and rabbit synovial fluid.

The simultaneous analysis of the molecular weight and concentration of hyaluronic acid in biological samples using high-performance liquid chromatography with two gel permeation columns is described. The elution volumes of various molecular weights of hyaluronic acids were linearily related to the logarithms of their molecular weights up to 600,000. The concentration of hyaluronic acid could be determined in the range from 20 to 100 micrograms/ml, i.e., from 4 to 20 micrograms per 200 microliter injected. The method was applied to the analysis of several animal skin extracts and rabbit synovial fluid. Skin extracts from mouse, rat, guinea-pig and rabbit could be chromatographed without prior isolation and purification. Hyaluronic acids in skin were separated clearly from chondroitin sulphates and their concentrations were determined. The molecular weights were estimated simultaneously to be more than 10(6). Rabbit synovial fluids from intact joints and saline- and carrageenin-treated joints could be chromatographed directly. The chromatograms showed that the concentration of hyaluronic acid in carrageenin-treated synovial fluid is lower than that in saline-treated fluid and the molecular weight distribution is broader. This technique enabled the rapid analysis of hyaluronic acid present at low levels in biological samples.

Animals↗
PubMed1988

Carcinoma of possible thymic origin presenting as a thyroid mass: a new subgroup of squamous cell carcinoma of the thyroid.

Intrathyroidal thymoma is a rare tumor that occurs in the thyroid gland and has been reported as a low-grade malignant tumor. The present report describes a 59-year-old male patient with this tumor, who was treated with subtotal thyroidectomy followed by radiation and chemotherapy. The tumor was located in the lower pole of the left lobe and the isthmus of the thyroid, and it had invaded the thyroid parenchyma, thyroid capsule, adjacent connective tissue, and neck muscles. Continuity between the cervical thymus and the tumor was noted. Subsequently, the patient developed widespread metastases in the liver, lungs, bones, and lymph nodes without local recurrence. Histologic examination disclosed a solid growth of epithelial cells with squamous cell differentiation and keratinization. The tumor cells had an ill-defined cell border and large nuclei with large nucleoli. Moderate mitoses and slight necrosis of the tumor were seen. Immunohistochemical examination showed that the tumor cells were stained positively for keratin but not for calcitonin or thyroglobulin. There were infiltrations of lymphocytes in the tumor and fibrous stroma, and most of them proved to be T cells.

Carcinoma, Squamous Cell↗
PubMed1988

Glycosaminoglycan polysulfate-induced stimulation of hyaluronic acid synthesis in rabbit knee synovial membrane: involvement of binding protein and calcium ion.

We have previously reported that naturally occurring sulfated glycosaminoglycans having a chondroitin-type structure and glycosaminoglycan polysulfate (GAGPS, a persulfated derivative of chondroitin sulfate) caused a specific stimulation of hyaluronic acid synthesis in rabbit knee synovial membranes [H. Nishikawa et al. (1985) Arch. Biochem. Biophys. 240, 146-153]. In the present study, the interaction of [3H]GAGPS and the surface of the rabbit knee synovial membranes and the relationship between this interaction and the stimulatory effect of GAGPS on the hyaluronic acid synthesis were examined in order to define the stimulatory mechanism of hyaluronic acid synthesis by GAGPS. A part of the [3H]GAGPS taken up by the synovial membranes was released from the membranes by trypsin treatment. The interaction of [3H]GAGPS and the surface of the isolated synovial membranes was diminished by pretreatment of the membranes with proteases or chelating reagents. Pretreatment of synovial membranes with trypsin or ethylene glycol bis(beta-aminoethyl ether) N,N'-tetraacetic acid had little effect on the basal hyaluronic acid synthesis but caused the loss of GAGPS-induced stimulation of hyaluronic acid synthesis accompanied by significant decrease (20% P less than 0.05-P less than 0.01) in the interaction between GAGPS and the surface of the synovial membranes. Dermatan sulfate having a chondroitin-type structure also stimulated hyaluronic acid synthesis but this effect was not additive to the stimulation of hyaluronic acid synthesis by GAGPS. Heparin had no effect on either the basal hyaluronic acid synthesis or the GAGPS-induced stimulation of hyaluronic acid synthesis. These results indicate that binding of GAGPS to certain distinct protein components on the surface of synovial membranes is involved in the stimulatory mechanism of hyaluronic acid synthesis by GAGPS, and that the binding may be mediated by Ca2+ ion. The binding was also found to be specific for sulfated glycosaminoglycans having a chondroitin-type structure.

Animals↗
PubMed1988

Transposable element Tc1 of Caenorhabditis elegans recognizes specific target sequences for integration.

The frequency of movement of Tc1, a 1.6-kilobase transposable element in the nematode Caenorhabditis elegans, is under genetic control, and Tc1 insertion sites are widely but nonrandomly distributed. The usually high frequency of insertions at multiple sites in the gene unc-22 suggested that this gene might be particularly rich in preferred target sites. To discover the features of Tc1 target sites, we have sequenced the sites of seven independent Tc1 transpositions into unc-22 and three other sites. Our comparison of these and two other sites from the literature indicates that in all cases Tc1 integrates at the dinucleotide T-A when it is flanked both 5' and 3' by particular preferred nucleotides. Our analysis revealed the following consensus target for Tc1 integration: G-A-K-A-T-A-T-G-T, in which K = G or T. This target site sequence specificity has implications both for the mechanism of Tc1 transposition and the use of Tc1 in cloning genes by transposon-tagging.

Animals↗
PubMed1988

Analysis of a mutator activity necessary for germline transposition and excision of Tc1 transposable elements in Caenorhabditis elegans.

The Tc1 transposable element family of the nematode Caenorhabditis elegans consists primarily of 1.6-kb size elements. This uniformity of size is in contrast to P in Drosophila and Ac/Ds in maize. Germline transposition and excision of Tc1 are detectable in the Bergerac (BO) strain, but not in the commonly used Bristol (N2) strain. A previous study suggested that multiple genetic components are responsible for the germline Tc1 activity of the BO strain. To analyze further this mutator activity, we derived hybrid strains between the BO strain and the N2 strain. One of the hybrid strains exhibits a single locus of mutator activity, designated mut-4, which maps to LGI. Two additional mutators, mut-5 II and mut-6 IV, arose spontaneously in mut-4 harboring strains. This spontaneous appearance of mutator activity at new sites suggests that the mutator itself transposes. The single mutator-harboring strains with low Tc1 copy number generated in this study should be useful in investigations of the molecular basis of mutator activity. As a first step toward this goal, we examined the Tc1 elements in these low copy number strains for elements consistently co-segregating with mutator activity. Three possible candidates were identified: none was larger than 1.6 kb.

Animals↗
PubMed1988

Induction of peroxisome proliferation in rat liver by dietary treatment with 2,2,4,4,6,8,8-heptamethylnonane.

1. Exposure of rats to 1% (w/w) of 2,2,4,4,6,8,8-heptamethylnonane in the diet for 2 weeks resulted in marked induction of liver peroxisome proliferation as judged from electron micrography, elevated activities of hepatic catalase (36%), cyanide-insensitive palmitoyl-CoA oxidase (10-fold), carnitine acetyl transferase (9.6-fold), lauric acid hydroxylase (12.4-fold), and the induction of the 80 K protein in SDS-polyacrylamide gel electrophoresis (4.1-fold). 2. 2,2,4,4,6,8,8-Heptamethylnonane dicarboxylic acid, a non-beta-oxidizable fatty acid, was detected as the major metabolite in the liver, an example of an unmetabolizable lipophilic anion as a peroxisome proliferator.

Alkanes↗
PubMed1988

[Effect of combined BCG and UFT therapy of human maxillary cancer transplanted into nude mice].

Twenty male 5-6 week-old nude mice transplanted with human maxillary cancer (MC-Ya) were divided into 4 groups. Group I was treated with oral administration of 0.2 ml of 0.9% saline solution daily for 10-30 days, and served as control. Group II was treated with oral administration of 1 mg/mouse of BCG once a week for 10-30 days. Group III was treated with oral administration of 15 mg/kg of UFT daily for 10-30 days. Group IV was treated with the combination therapy of BCG and UFT. In comparison of the treatment effects in 4 groups, following results were obtained: 1) Mouse immunosuppressive acidic protein in the sera of nude mouse elevated in all groups, especially in group III. 2) The inhibitory effect on the growth of tumor was observed in group III and IV, especially in group IV, but not in group II. 3) The reason why the growth-inhibitory effect was observed more remarkably in group IV than in group III, would be explainable as the immunosuppression by UFT was restored by the immunostimulating effect of BCG.

Administration, Oral↗
PubMed1988

[Metastatic calcification associated with malignancy].

From 1975 to 1986, 15 cases (2%) of metastatic calcification associated with an underlying malignancy were found in a review of 702 autopsied cases with histories of malignancy. These underlying malignancies included 7 cases of lung cancer, 6 cases of malignant lymphoma, one case of breast cancer, and one of urinary bladder cancer. Squamous cell carcinoma was of the histological type most often associated with metastatic calcification in lung cancer, and ATL in malignant lymphoma. Hypercalcemia was found in 10 (83%) out of cases, and almost all were accompanied by renal dysfunction. Calcium deposits were most frequently observed in the kidneys and the lungs. It has been suggested that metastatic calcification in the lungs and kidneys of a patient with a history of malignancy showing hypercalcemia is sometimes accompanied by respiratory and renal dysfunction, causing the patient's condition to deteriorate.

Adult↗
PubMed1987

Temporal and spatial heterogeneity of mtDNA polymorphisms in natural populations of Drosophila mercatorum.

Restriction endonuclease analysis of mtDNA was used to examine the genetic relatedness of several geographically separated isolines of the Drosophila mercatorum subgroup. In addition, we examined the temporal and spatial distribution of two mtDNA restriction site polymorphisms produced by the enzymes BstEII and BstNI at a single locality--Kamuela, Hawaii. Due to small sample sizes of some collections and the undesirable dependance of the estimation of polymorphism frequency on its variance, an arcsin square root transformation of the frequency data was used. We also use an Fst estimator of our transformed frequencies to demonstrate considerable spatial and temporal differentiation within the Kamuela population. In contrast, isozyme data from the same population reveals no pattern of differentiation. The temporal and geographic heterogeneity and population subdivision detected with mtDNA analysis also is consistent with the known dispersal behavior and ecological constraints of this species. The mtDNA data in conjunction with the isozyme data show that the population structure of the Kamuela D. mercatorum is close to the boundary line separating panmixia from subdivision, a conclusion that could not be made from isozyme data alone.

Alleles↗
PubMed1987

[Dubin-Johnson syndrome associated with hepatocellular carcinoma--report of an autopsy case].

An autopsy case of Dubin-Johnson syndrome (DJS), associated with hepatocellular carcinoma (HCC), the third such case in Japanese literature, is reported. A 64-year-old man, known to have had jaundice from his childhood, was admitted because of weight loss. Close examination revealed that the patient had DJS with HCC and a right lobectomy of the liver was performed. He died, however, of metastasis of HCC about 36 months later. At autopsy, the liver was found to be brownish-black in color. Microscopic findings of the liver were those common to HCC and chronic active hepatitis, and the brown pigment seen in the hepatocytes was mainly confined to the centrilobular ares. After histochemical and electronmicroscopic study, a close relation between this pigment and lysosome is suspected.

Carcinoma, Hepatocellular↗