Search PubMed⌕ Search

Biomedical subjects

M Umeda

Publications and source records attributed to M Umeda.

At least 181 records · Page 10Linked to original sources
PubMed1996

Slowing of peripheral motor nerve conduction was ameliorated by aminoguanidine in streptozocin-induced diabetic rats.

The aims of this study were to investigate the effect of aminoguanidine (AG) on slowing of motor nerve conduction velocity (MNCV) of the sciatic nerve in streptozocin-induced diabetic rats and to assess its mechanism of action. The MNCV of the sciatic nerve was measured electrophysiologically in diabetic rats treated with and without AG for 16 weeks. To elucidate the action of AG, morphological lesion and abnormality of polyol pathway metabolism in the nerve were examined and tissue levels of advanced glycosylation end-products (AGE) were determined as an indicator of AGE accumulation in tissue. Diabetic rats were treated with AG at three doses of 10, 25 and 50 mg/kg for 16 weeks. Myelinated fiber morphometry and nerve Na+,K(-)-ATPase activity were determined. The AGE levels in renal cortex were measured by a specific ELISA. Aminoguanidine dose-dependently ameliorated slowing of MNCV 16 weeks after the treatment without changing body weight or blood glucose levels. No difference in myelinated fiber morphometry or Na+,K(+)-ATPase activity with or without AG treatment was detected in diabetic rats. Diabetes increased the AGE level in the renal cortex by six times compared to non-diabetic rats, and AG reduced the rise in the AGE level by 40%. The MNCV was inversely correlated with the AGE levels. We conclude that improvement of conduction slowing by AG in experimental diabetes may be through decreasing the AGE level in the peripheral tissues. Aminoguanidine may have a therapeutic potential in controlling diabetic peripheral neuropathy.

Animals↗
PubMed1996

Microbial flora in the acute phase of periodontitis and the effect of local administration of minocycline.

Periodontitis, similar to other infectious diseases, is known to progress as chronic inflammation with recurrent acute phases. The purpose of this study was to clarify the microbiological composition of the acute phase and to compare the bacterial flora with that of comparable chronic periodontal pockets. We also evaluated the effect of application of minocycline gel locally on the change in the microflora in the acute pockets. Microbial flora from the subgingival pockets of 28 patients in the acute phase of periodontitis and of 12 patients in a comparable chronic phase as the control were investigated by various bacterial culture methods including TS blood agar and TSBV plates. Minocycline gel was applied to the acute periodontal pockets. Changes in the microbiological proportion and clinical parameters at one week after baseline examination were followed by dark-field analysis, culture method, and indirect immunofluorescence technique. Characteristic features of bacterial proportions in the acute site were observed as an increase in Bacteroides forsythus. The number of Porphyromonas gingivalis and black pigmented anaerobic rods also increased. Application of minocycline gel in the acute pocket without any debridement produced improvement in clinical symptoms at one week. Black-pigmented anaerobic rods, P. gingivalis, and B. forsythus decreased significantly at one week after the application. Results indicate that periodontopathic bacteria including B. forsythus and P. gingivalis were predominant in the acute phase of periodontitis and a locally delivered antibiotic may be effective as an alternative modality of treating the acute inflammation.

Acute Disease↗
PubMed1996

Characterization of cDNA encoding for phosphoglucose isomerase of rice (Oryza sativa L.).

Two types of genes (Pgi-a and Pgi-b) encoding phosphoglucose isomerase (PGI; EC 5.3.1.9) were cloned from cDNA libraries of rice cultured cells (Oryza sativa L.). Pgi-a and Pgi-b consisted of 2132 and 2030 nucleotides, respectively. The homology between these genes was 93.0% at nucleotide level. The homology scores between these genes in protein coding region and 3' non-coding region were 95.6% and 79.4%, respectively. PGI proteins encoded by Pgi-a and Pgi-b consisted of 567 and 568 amino acid, respectively, sharing 95.8% homology at amino acid sequences. Of 11 PGI genes from other plant species and organisms whose amino acid sequences had been determined, a dicotyledonous plant Clarkia lewisii PGI showed the highest homology (about 80%) with rice PGIs. GC contents at the third position of rice PGI genes were about 40%. In order to confirm the enzyme activity of the protein encoded by the rice cDNA, Pgi-a was subcloned into an expression vector, pBluescript II SKp, which was introduced into Escherichia coli. The transformant had an additional PGI activity from Pgi-a.

Amino Acid Sequence↗
PubMed1996

Novel DNA probes capable of discriminating indica and japonica rice cultivars.

We obtained two DNA clones, G93 (1.6kb) and G318 (1.7kb) from indica rice (Oryza sativa L.) cultivar Culture 340. Southern hybridization analysis indicated that both DNA probes hybridized with DNA of indica cultivars but not with japonica cultivars. Some javanica cultivars DNAs did not hybridize with these probes. Nucleotide sequence (400bp) of a part of G93 showed a 65.8% G + C content. These novel DNA probes can be used for the study of evolutional fingerprinting of rice cultivars.

Base Sequence↗
PubMed1996

[Double cancer in elderly patients with hematologic malignancies].

The occurrence of multiple malignancy was studied in 674 patients with hematologic malignancies who were admitted to this department during the past 10 years. Of the 674 patients, 205 were aged 65 years or older, and 56 (8.3%) had another cancer. The frequency of multiple malignancy was significantly higher in older patients than in younger patients: 44 (21.5%) vs. 12 (2.6%). The major hematologic conditions in patients with multiple malignancy were multiple myeloma, myelodysplastic syndromes, non-Hodgkin's lymphoma, and chronic myelogenous leukemia. The major sites of cancers other than hematological malignancies were the stomach, colon, breast, and esophagus. Many of the older patients had gastric cancer or colon cancer, and gastric cancer was common in the younger patients. The multiple malignant neoplasms were synchronous in as many as 20 of the 44 older patients. There was only one such case among the younger patients. Of the 56 patients, nine had received alkylating agents, and one has received etoposide. In brief, elderly patients with hematologic malignancies are likely to have multiple malignant neoplasms. If they are synchronous, the patient's prognosis may be adversely affected, because simultaneous management of multiple malignant neoplasms is not easy.

Aged↗
PubMed1996

[Evaluation of non radioactive DNA probe (Affirm DP) for detecting periodontopathic bacteria].

The purpose of this investigation was to evaluate the potential of application of non-radioactive DNA probe method (Affirm DP) in clinical diagnosis and evaluation of treatment efficacy. Sensitivity and specificity of two different cut-off levels (10(4), 5 x 10(5)) of the method with bacterial culture in detection of Bacteroides forsythus, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans were compared. Those bacteria were obtained from bacterial cultures and clinical samples from healthy subjects and patients with periodontal disease. The results showed that detection percentage of DNA probe method with 10(4) cut-off was equal to or higher than the culture method for Bacteroides forsythus and Porphyromonas gingivalis detection. Therefore, it is suggested to be a useful chairside DNA probe kit as an aid in clinical diagnosis and evaluation of treatment efficacy.

Aggregatibacter actinomycetemcomitans↗
PubMed1996

[Classification of patterns of nocturnal penile tumescence with continuous monitoring of penile rigidity: analysis of various factors affecting erection].

In 43 men who required further examination of erectile function, we analyzed the relationship between the various factors including hormone levels, penile blood pressure index (PBPI), shape of the arterial wave, erection period after prostaglandin E1 injection and dynamic cavernosography/metry, as well as the patterns of nocturnal penile tumescence (NPT) with rigidity. Normal, dissociation, short episode, low amplitude and flat trace patterns, which were classified by Kaneko, were observed in 11, 8, 11, 2 and 11 men, respectively. Uncoupling was not observed in any men. There were no differences in the levels of prolactin and LH among the 6 patterns. A high FSH level was seen in men with a flat trace pattern; a low level of free testosterone ( < 12.2 pg/ml) was seen in men with dissociation, low amplitude and flat trace patterns, and low PBPI ( < 0.75) in men with flat trace pattern; and an arteriosclerotic shape of the arterial wave was seen in men with short episode and flat trace patterns. Each erection period immediately after prostaglandin E1 injection in men with dissociation, short episode, low amplitude and flat trace was shorter compared with cases with a normal pattern. Venoocclusive dysfunction was observed in 5 men with a dissociation pattern and 6 men with a flat trace pattern. In conclusion, an integral analysis of pattern of NPT with rigidity and other examinations are useful for differentiating organic impotence from psychogenic impotence and for accurately diagnosing pathophysiological disorders of organic impotence and underlying diseases.

Adult↗
PubMed1996

Specific cross-reaction of IgG anti-phospholipid antibody with platelet glycoprotein IIIa.

To study the pathological functions of anti-phospholipid (anti-PL) antibodies, we have analyzed their effect on platelet function. We identified an IgG anti-PL mAb, designated PSG3, which cross-reacted specifically with glycoprotein (GP) IIIa in human platelets and inhibited platelet aggregation. PSG3 bound also to certain polyanionic substances, such as double-stranded DNA, heparan sulfate, dextran sulfate and acetylated-LDL, but not to other polyanionic substances. The binding of PSG3 to GPIIIa was completely inhibited by heparan sulfate and dextran sulfate, indicating that PSG3 recognizes a particular array of negative charges expressed on both GPIIIa and the specified polyanionic substances. Since neither neuraminidase- nor endoglycopeptidase F-treatment of GPIIIa had any significant effect on the binding of PSG3, this array must be located within the amino acid sequence of GPIIIa but not in the carbohydrate moiety. Reduction of the disulfide bonds in GPIIIa greatly reduced its reactivity, suggesting that the negative charges in the epitope are arranged in a particular conformation. PSG3 inhibited platelet aggregation induced by either ADP or collagen, it also inhibited fibrinogen binding to activated platelets in a dose-dependent fashion. PSG3, however, did not inhibit the binding of GRGDSP peptide to activated platelets. These results suggest that the PSG3 epitope on GPIIIa contains a particular array of negative charges, and possibly affects the fibrinogen binding to GPIIb/IIIa complex necessary for platelet aggregation.

Amino Acid Sequence↗
PubMed1996

[Clinical usefulness of 123I-BMIPP (beta-methyl iodophenyl pentadecanoic (acid) myocardial SPECT in patients with hematological malignancies with adriamycin-induced cardiomyopathy].

In order to investigate myocardial lipid metabolism in patients receiving chemotherapy regimens containing adriamycin (ADR) for hematological malignancies, 123I-beta-methyl iodophenyl pentadecanoic acid (BMIPP) myocardial SPECT was performed. Thirty-two patients with hematological malignancies received a mean total ADR dose of 245 mg/m2 (range: 0-550 mg/m2). A polar map based on data from 8 normal individuals was used to calculate the extent score (representing the area of decreased uptake) and the severity score (representing the severity of defects) in the patients given ADR. 1) There was a significant association between the total ADR dose and the extent and severity scores. 2) The left ventricular ejection fraction was significantly associated with the extent and severity scores. 3) The two scores were also significantly associated with the washout rate of 123I-metaiodobenzylguanidine (MIBG). These results suggest that 123I-BMIPP myocardial scintigraphy reflects dysfunction of the myocardial mitochondria and serves as a guide for determining whether administration of ADR should be discontinued or the dose reduced.

Antibiotics, Antineoplastic↗
PubMed1996

[8;21 translocation acute myelocytic leukemia developing in the second trimester of pregnancy with successful delivery].

A 28 year-old woman in the 26th week of pregnancy was admitted to our hospital on February 6, 1993, because of anemia and thrombocytopenia. On admission, her hemoglobin was 8.2 g/dl, platelet count 6.3 x 10(4)/microliter, and WBC 6,300/microliter with 43% blasts. The bone marrow examination showed hyperplastic bone marrow with 38.8% blasts. She was diagnosed as having 8;21 translocation acute myelocytic leukemia (M2). In the 30th week of pregnancy, she gave birth to a 1449 g male infant by induction delivery. After DCMP therapy, complete remission was obtained. She has been in complete remission for 32 months and her child is growing healthy after overcoming an underweight condition due to premature birth, respiratory distress syndrome, circulation insufficiency and hyperbilirubinemia. This case suggests that in the event of second trimester pregnant patients with acute leukemia, we should wait for the proper time at which successful delivery can be expected, and then intensified remission induction chemotherapy should be carried out after the delivery.

Adult↗
PubMed1995

A novel phosphatidylserine-binding peptide motif defined by an anti-idiotypic monoclonal antibody. Localization of phosphatidylserine-specific binding sites on protein kinase C and phosphatidylserine decarboxylase.

A monoclonal anti-idiotypic antibody, Id8F7, previously shown to bind to a phosphatidylserine (PS)-specific binding site on protein kinase C (PKC) has been used to identify a 12-amino acid consensus sequence shared by PKC and phosphatidylserine decarboxylase (PSD). The 14-amino acid synthetic peptide derived from the corresponding region of PSD (amino acids 351-364 of the enzyme from Chinese hamster ovary cells) bound effectively and specifically to PS, and that derived from rat PKC gamma (amino acids 227-240) bound weakly but specifically to PS. Analysis of binding of Id8F7 to various synthetic peptides revealed that the consensus sequence motif, FXFXLKXXXKXR, is responsible for the interaction with both Id8F7 and PS. The results suggest that the conserved amino acid residues represent a basic structural motif for the specific interaction with PS, and the corresponding regions of PKC and PSD form the PS-specific binding sites of these enzymes.

Amino Acid Sequence↗
PubMed1995

Trypsinogen expression in human ovarian carcinomas.

Increased secretion of matrix metalloproteinases and serine proteinases is well known to be associated with cancer invasion and metastasis. We aimed to elucidate the implication of trypsin, a serine proteinase and a representative digestive enzyme in invasion and metastasis of human carcinomas. Northern blot, RT-PCR and Western blot analyses and immunohistochemical studies were performed to detect and analyze trypsinogen expression in 5 ovarian carcinoma cell lines and 10 human ovarian carcinoma tissues using a DNA probe for trypsinogen I, and monoclonal and polyclonal antibodies to human trypsin I. Among the 5 ovarian carcinoma cell lines, only the MCAS (mucinous cystadenocarcinoma) cell line showed a high level of trypsinogen production and mRNA expression by Western and Northern blot analyses, respectively. However, Southern blot analysis of RT-PCR products could detect considerable levels of trypsinogen mRNA in all ovarian cancer cell lines. In Northern analysis of ovarian cancer tissues, all advanced cancer samples showed trypsinogen gene expression. Serous cystadenocarcinomas exhibited particularly high levels of gene expression. Immunohistochemical staining also detected trypsin in ovarian carcinoma tissues. In contrast, normal ovaries and tumors with low malignant potential did not show trypsinogen expression. Our results demonstrate the extra-pancreatic production and distribution of trypsinogen in human ovarian carcinomas.

Adenocarcinoma↗
PubMed1995

Characterization of glycosylphosphatidylinositol (GPI)-anchored NCAM on mouse skeletal muscle cell line C2C12: the structure of the GPI glycan and release during myogenesis.

The mouse myoblast cell line C2C12 constitutively expressed 160-kDa transmembrane NCAM isoform and 135-kDa GPI-anchored isoform before differentiation. During differentiation into multinucleated myotubes, the cells newly expressed 150-kDa GPI-anchored isoform and the level of 135-kDa GPI-anchored isoform increased. Structural analysis of the GPI glycan of NCAM, which was purified from C2C12 myotubes after metabolic labeling with [3H]inositol, was performed by sequential exoglycosidase digestion and Wistaria floribunda agglutinin-agarose column chromatography. The core GPI glycan structure, Man alpha 1-2Man alpha-Man alpha-GlcNH2-myoInositol, was conserved and variations were observed in additional mannose and N-acetylgalactosamine residues. Structural analysis of the GPI glycans of the two GPI-anchored isoforms, GPI-NCAM 135 and GPI-NCAM 150, showed the enhanced attachment of the N-acetylgalactosamine residue to the GPI glycan core of GPI-NCAM 150. These GPI-anchored NCAM isoforms were released from C2C12 cells during the myoblast differentiation. Release of GPI-anchored NCAMs was observed when C2C12 cells were cultured in a serum-free medium, and inositol but not inositol phosphate was detected after nitrous acid deamination of the released NCAM. These results suggest that the GPI-anchored NCAM was released from the cell surface by the action of an endogeneous phospholipase D.

Animals↗