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Biomedical subjects

M Kitamura

Publications and source records attributed to M Kitamura.

At least 19 recordsLinked to original sources

Gene expression of metalloproteinase and its inhibitor in mesangial cells exposed to high glucose.

To clarify the roles of metalloproteinases and their inhibitor (TIMP) in diabetic glomerulopathy, we studied the effect of a high glucose concentration on the gene expression of metalloproteinase transin and TIMP as well as collagen type IV and laminin in cultured rat mesangial cells (MCs). In the high glucose group, collagen type IV, laminin, and TIMP mRNA levels were all elevated in a concentration-dependent manner, whereas transin expression was suppressed. Osmotic control of high glucose with mannitol selectively stimulated TIMP expression. We hypothesize that high glucose decreases matrix-degrading activity as well as increases matrix productivity in MCs.

Animals

Molecular characterization of genetic mutations in human lactate dehydrogenase (LDH) B (H) variant.

We have previously detected a single base substitution of G by A at the Arg codon CGC in exon 4 of the mutant lactate dehydrogenase (LDH) gene, an unstable LDH-B variant (case 1). Here, we use the polymerase chain reaction (PCR) to amplify genomic DNA of two cases (the original case 1 and a new patient, case 2). We were able to confirm that case 1 is homozygous for the mutation, causing a replacement of the conserved Arg by His at residue 173. The resulting LDH-B variant subunit is unstable in vivo. Whereas the mutation in exon 4 was not observed in case 2, a different single base substitution of A by C was detected at the Ser codon AGT in exon 3. This mutation causes a replacement of the conserved Ser by Arg at residue 131. Genomic analysis of the family of case 2 by mismatched PCR showed that the missense mutation was consistent with their biochemical phenotypes. The replacement results in a conformational change of the residues near the Ser, probably because the side chain of Arg is much more bulky than that of Ser. The change may affect the arrangement of the cofactor binding site and result in the loss of enzyme activity. The experimental observations are consistent with computer graphics analyses.

Amino Acid Sequence

Extracellular matrix contraction by cultured mesangial cells: modulation by transforming growth factor-beta and matrix components.

Cultured glomerular mesangial cells (MCs) have the ability to contract the surrounding collagen gel matrix (CGM). To investigate this phenomenon, we examined the effect of growth factors and extracellular matrix (ECM) components. Among some growth factors tested, transforming growth factor-beta (TGF-beta) and fetal calf serum (FCS) enhanced CGM contraction dose dependently. These factors acted through distinct mechanisms because: (1) when growth-arrested MCs were used, the effect of FCS was inhibited partially but that of TGF-beta was not; and (2) anti-TGF-beta had no influence on CGM contraction induced by FCS. Among the ECM components such as laminin, fibronectin, type IV collagen, and heparin-like proteoglycans (heparan sulfate and heparin), which were each mixed separately with CGM before gelling, heparin-like proteoglycans and type IV collagen inhibited contraction by MCs. The inhibitory effect of heparin was mediated by the interaction both with CGM and with MCs because: (1) when heparin was added to the culture medium, not into the gel, the inhibitory effect was diminished but still noted; and (2) using growth-arrested MCs, the inhibitory effect of heparin in the medium was reduced but still observed. This culture assay is useful for elucidating the tensional interaction between MCs and surrounding ECM.

Animals

Cytokine gene expression in rejecting cardiac allografts.

Heart transplantation is now a viable therapeutic option for patients with certain end-stage cardiac diseases. However, episodes of rejection, opportunistic infection, and life-threatening side effects of generalized immunosuppression remain very real problems for these patients. A better understanding of the molecular mechanisms underlying rejection may provide the basis for the development of more specific, less toxic immunosuppressive therapies. While cytokines have long been implicated in the pathogenesis of rejection, the precise role of each cytokine in this process has yet to be defined. We report here the application of the polymerase chain reaction (PCR) to the detection of cytokine mRNA in biopsies obtained from heterotopic abdominal cardiac allografts in cynomolgus monkeys. With the exception of IL-6 and IL-8, cytokine transcripts were undetectable in samples obtained from the donor heart pretransplant. In contrast, IFN-gamma transcripts were detected in all transplants two days after surgery before evidence of rejection was demonstrable by histopathologic analysis. IL-1 beta, IL-2, and IL-6 transcripts were detected when minimal rejection was noted. At later times, IL-1 alpha, IL-1 beta, IL-2, IL-6, IL-8, TNF-beta, and IFN-gamma transcripts were detectable. Further characterization of the spectrum of cytokines expressed at various stages of rejection may lead to insights into the biology of transplant rejection and to the development of more specific and potent reagents to diagnose and/or treat rejection.

Animals

Induction of endogenous retroviral gene product (SU) as an acute-phase protein by IL-6 in murine hepatocytes.

The effect of Lps locus and IL-6 on the production of SU (previously termed gp70), a mouse endogenous retroviral gene product, was studied. Back-cross studies using the progeny between (NZB x C3H/HeJ)F1 and C3H/HeJ mice indicate that the basal level of SU is not associated with the Lps locus on chromosome 4. Lipopolysaccharide (LPS) mitogen response-negative mice did not show the enhancement of serum SU production after LPS injection. Spleen cells from LPS-mitogen response-positive but not from negative mice showed increase of IL-6 synthesis in the presence of LPS. Since IL-6 may be involved in the production of serum SU, we tested the effect of IL-6 in a primary hepatocyte culture system. SU production was clearly enhanced in the presence of recombinant IL-6, indicating that IL-6 induced by LPS can enhance the expression of retroviral genome.

Acute-Phase Proteins

Locoregional control for esophageal carcinoma treated with irradiation following surgery.

Locoregional failure was analyzed in a total of 34 esophageal carcinoma patients treated with postoperative prophylactic irradiation following curative surgery. All patients had squamous cell carcinoma and no prior treatment. Twelve patients had subsequent lymph node metastasis in the follow-up period. In the 12 patients with node metastasis, there were 5 instances of supraclavicular node metastasis, 7 instances of thoracic inlet node (uppermost part of mediastinum) metastasis, and 3 instances of mediastinal node metastasis. Three patients had 2 metastatic nodes and 9 patients had 1 metastatic node. Intervals between surgery and recurrence were a median of 12 months for mediastinal nodes, 19 months for thoracic inlet nodes, and 26 months for supraclavicular nodes. Ten (52.6%) of the 19 patients treated by using a 12-MeV electron beam had metastatic involvement at the supraclavicular and thoracic inlet nodes. On the other hand, 2 (13.3%) of the 15 patients had the above-described lymph node metastases when treated by using 15-MeV electron, 18-MeV electron, or 10-MV photon beams. The difference in the metastatic rate between these two groups was statistically significant at the level of p < 0.05 (chi-square test); this seems to be attributable mainly to the dose level at deep region. Doses of over 50 Gy to the thoracic inlet and supraclavicular nodes at deep location were necessary to reduce metastasis.

Adult

[Clinical significance of measuring glycated fibrinogen in plasma in diabetes mellitus].

The clinical significance of measuring glycated fibrinogen (G Fbg) in plasma was studied using a simple, rapid method for determining plasma G Fbg developed by the authors. This method is based on modified fibrin clot formation for purification of plasma Fbg, and G Fbg was estimated by improved colorimetric fructosamine assay. The values of plasma G Fbg were expressed as glycated polylysine equivalents (mumol/l). In this clinical study, 106 examinees who underwent a screening test for diabetes mellitus (DM) because of glycosuria or hyperglycemia were investigated. According to the WHO diagnostic criteria, they were divided into 3 groups: non DM group (n = 35), impaired glucose tolerance (IGT) group (n = 31) and DM (non-treated) group (n = 40). In addition, healthy controls (n = 40) and treated diabetic patients (DM treated) were involved. Plasma G Fbg/Fbg, fasting plasma glucose (FPG), fructosamine and glycated hemoglobin (HbA1c) were also analyzed in subjects of the 5 groups. Non-treated DM patients showed high levels of plasma G Fbg, which were significantly higher than those of any other groups. G Fbg levels in IGT group were significantly higher than those in healthy controls or the non-DM group. Together with a significant positive correlation between G Fbg and FPG, these results indicate that the levels of plasma G Fbg depend on plasma glucose levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Syntheses of oligonucleotide derivatives with P(V) porphyrin and their properties.

Two types of oligonucleotide derivatives which are substituted by P(V) porphyrin at the phosphorus atom of an internucleotidic linkage and at the 5'-terminal internucleotidic linkage via a spacer were synthesized (Fig. 1), and hybridization capabilities of them with complementary oligonucleotides were evaluated. A novel method for a sensing of oligonucleotide by the fluorescence quenching via photo-induced electron transfer between the P(V) porphyrin labeled oligonucleotide and pyrene-labeled one on the oligonucleotide template is reported.

Base Sequence

[A case of hepatocellular carcinoma responding to intraarterial infusion of epirubicin and mitomycin C].

A 64-year-old male was admitted for treatment of hepatocellular carcinoma. He was diagnosed as having many tumors in the area of S6 and the AFP level was elevated to 878 ng/ml. Initially, intraarterial infusion of Epirubicin only was not effective. After the first course of treatment, tumors increased in size and the AFP level was elevated. Next, intraarterial infusion of Epirubicin and Mitomycin C was performed. After the second course of treatment, the AFP level decreased from 5,006 ng/ml to 754 ng/ml and the tumors had almost completely disappeared on angiography. The tumors continued to decrease in size and thereafter the AFP level decreased to 10 ng/ml and was not elevated. The tumors almost completely disappeared in this case, and the coadministration of Epirubicin and Mitomycin C provided effective.

Antineoplastic Combined Chemotherapy Protocols

[Cervical esophago-gastrostomy via the posterior mediastinal route for carcinoma of the thoracic esophagus].

From 1981 to 1990, 297 cases of carcinoma of the thoracic esophagus were resected in our department. Among these cases, 225 cases (84.3%) were reconstructed cervical esophagogastrostomy via the posterior mediastinal route. In this paper, these 225 cases were analysed to evaluate the usefulness of this procedure which was developed by S. Abo in 1975. Operative mortality was 4.4% Anastomotic leakage occurred in 24.4% of the cases, but the majority of the cases were treated successfully without any drainage and 83.3% of the cases could start their diet within one month after operation. The volume of oral intake by the patients after discharge increased satisfactorily (1,500-1,800 kcal/day), but the body weight decreased gradually. So the ambulatory enteral nutritional support was started and proved useful for maintaining their body weight. Alkaline reflux evaluated using 24-hour pH-monitoring system was observed in about half of the cases but the degree of the alkaline shift was not strong. Some complaints (heart burn in 6.3%, regurgitation in 21.9%, feeling of fullness after eating in 40.6%, stenotic sensation in 20.7%) were present but not serious.

Body Weight

Plasmapheresis in the Tokai University Medical Center, 1983-1989.

There were 634 instances of plasmapheresis performed on 152 patients in the Kidney Center, Tokai University Hospital, in the seven year period from Jan. 1983 to Dec. 1989. The average number of plasmapheresis treatments per patient was highest for those with neurological and dermatological disease (6.7), followed by liver disease (5.6), and drug intoxication (1.2). The major treatment modalities for the liver, collagen, drug intoxication, hematologic, neurologic and hyperlipidemic disorders were plasma exchange (PE) and double filter plasmapheresis (DFPP). Recently, however, the use of plasma perfusion (PP) and immunoadsorbent plasma perfusion (IPP) has been increasing because of their ability to selectively adsorb various pathologic macromolecules.

Collagen Diseases

[DNA ploidy pattern as an indicator of degree of malignancy and prognosis in gastric cancer].

We used fresh materials and paraffin blocks of advanced gastric cancer to examine the relationship of DNA ploidy pattern from flow cytometry (FCM) to degree of malignancy and prognosis. No significant relationship was found between the frequency of DNA aneuploid (DA) and the clinicopathological factors (depth of invasion, degree of progression, histological type, lymph node metastasis, ly, v etc.). FCM examination using fresh materials revealed significant difference in prognosis between the non-DA and DA groups for non-curative stage III or IV cases (p < 0.05). On the other hand, in terms of the relationship between DNA ploidy patterns from paraffin blocks and prognosis for curative resection cases of ss-gastric cancer, prognosis was significantly better in the non-DA group than in the DA (p < 0.01). These results indicate that the clinicopathological prognostic factors for gastric cancer are connected in a complex way and that DNA ploidy patterns alone are not superior to the prognosis determining factors used in the past.

Aged

[A case of congenital esophago-bronchial fistula communicated between esophageal diverticulum and left main bronchus in the adult--a review of 47 cases in the Japanese literature].

We experienced a successful repair of congenital esophago-bronchial fistula communicated between esophageal diverticulum and left main bronchus in adult case. The patient was a 60-year-old female. She had much wet cough on taking meals since 10 years ago. At the mass screening, a esophago-bronchial fistula was detected by upper GI series. Barium esophagography revealed a fistula between esophageal diverticulum and left main bronchus. The resection of diverticulum and fistula were undergone. In the operation, there exited no adhesion or inflammation around the fistula, therefore it was easy to isorate from the surrounding tissues. This case was categorized as Brainbridge type I esophago-bronchial fistula communicated to left main bronchus. Forty-six cases of congenital esophago-bronchial fistula with diverticulum were reported in Japan, but no cases which communicated with left main bronchus were reported. Then it is assumed that this is the first case in Japan.

Bronchial Fistula

[Complications related to catheter indwelling in intra-arterial infusion chemotherapy from the standpoint of the route of cannulation].

Eighty-one cases of advanced gastric cancer, who had been treated by intra-arterial infusion chemotherapy, were examined for complications related to catheter indwelling. Subjects consisted of 46 cases of aortic cannulation (via femoral artery, 29; via subclavian artery, 17) and 35 cases of hepatic cannulation (via laparotomy, 29; via subclavian a, 6). As the result, complications were more frequent in the cases via femoral (24.1%) and via laparotomy (41.4%), whereas there was only one case in subclavian route. Six cases (67%) of dislocations developed within one month after cannulation and occlusions (8 cases) were often found in cases of one shot or non-injection. In conclusion, cannulation via subclavian artery is an excellent method.

Antineoplastic Agents