Search PubMed⌕ Search

Biomedical subjects

N Fujimoto

Publications and source records attributed to N Fujimoto.

At least 127 records · Page 7Linked to original sources
PubMed1996

Interaction between tissue inhibitor of metalloproteinases-2 and progelatinase A: immunoreactivity analyses.

By immunoreactivity analysis using monoclonal antibodies, we showed that the C-terminal domain [R415-631; R is residue] of progelatinase A [pro-matrix metalloproteinase-2 (proMMP-2); EC 3.4.24.24] affected the immunoreactivity of a one-step sandwich enzyme immunoassay (sandwich EIA) for tissue inhibitor of metalloproteinases-2 (TIMP-2) in exactly the same way as does proMMP-2 [Fujimoto, Zhang, Iwata, Shinya, Okada and Hayakawa (1993) Clin. Chim. Acta 220, 31-45], confirming that the C-terminal domain ("tail" portion of TIMP-2 participates in the binding with the C-terminal domain of proMMP-2. We also demonstrated that not only the C-terminal domain but also the N-terminal domain (R1-417) of proMMP-2 bound to TIMP-2 in a 1:1 molar ratio. The binding of each individual domain to TIMP-2, however, was weak enough that either domain could be fully replaced by proMMP-2 through the same binding sites as does proMMP-2, and also that the high-order structure of proMMP-2 allows a more stable binding to TIMP-2. We further confirmed that TIMP-2 complexed with the N-terminal domain of pro-MMP-2 had fully inhibitory activity against the collagenolytic activity of MMP-1. We also demonstrated that either the interstitial collagenase-TIMP-2 complex or the gelatinase B(MMP-9)-TIMP-2 complex was able to form a ternary complex with proMMP-2 in a 1:1 molar ratio, clearly indicating that there are two distinct binding sites, one specific for proMMP-2 complex, but the binding seemed to be less stable than the binding with TIMP-2 alone. Even in the presence of a 10-fold molar excess of the N-terminal domain, ternary complex formation was not observed between the N-terminal domain and the MMP-9--TIMP-2 complex. These clear differences might be ascribed to some significant conformational change(s) evoked in the TIMP-2 molecule, or hindrance of a part of the N-terminal domain binding site of TIMP-2 by complex formation with MMP-9.

Animals↗
PubMed1996

A one-step sandwich enzyme immunoassay for human matrix metalloproteinase 8 (neutrophil collagenase) using monoclonal antibodies.

A one-step sandwich enzyme immunoassay (EIA) system for human matrix metalloproteinase 8 (MMP-8, neutrophil collagenase, EC 3.4.24.7) has been established with a pair of monoclonal antibodies prepared against the zymogen of MMP-8 purified from human neutrophils. MMP-8 in samples simultaneously reacted with both solid-phase and peroxidase-labeled antibodies. Sensitivity of this EIA system was 0.34 micrograms/l (5.7 pg/assay) and linearity was obtained between 0.5 and 500 micrograms/l (8.3-8300 pg/assay). The EIA system recognized both precursor and active forms of MMP-8 but not MMP-8 complexed with tissue inhibitors of metalloproteinases. There was no difference in the MMP-8 levels between the plasma samples from patients with rheumatoid arthritis or osteoarthritis and those from healthy subjects (median 6.2 micrograms/l, range 1.5-28 micrograms/l). However, the level in synovial fluids from patients with rheumatoid arthritis (median 345 micrograms/l, range 84-2860 micrograms/l) was shown to be higher than that from osteoarthritic patients. MMP-8 levels in human whole saliva from patients with periodontal diseases (median 282 micrograms/l, range 0-1420 micrograms/l) were also significantly higher than those from clinically healthy subjects (median 25 micrograms/l, range 0-100 micrograms/l). Immunoreactivity analyses showed that MMP-8 species in normal human plasma exists as a precursor but not as a complex form with tissue inhibitor of metalloproteinases (TIMP)-1 or TIMP-2.

Animals↗
PubMed1996

Secretion of matrix metalloproteinase-2 (72 kD gelatinase/type IV collagenase = gelatinase A) by malignant human glioma cell lines: implications for the growth and cellular invasion of the extracellular matrix.

Human glioma cells (T98G and A172 cell lines) were cultured on various extracellular matrix (ECM) components including type I, IV and V collagens, fibronectin, laminin, and reconstituted basement membrane (Matrigel), and the role of matrix metalloproteinases (MMPs) in their growth and invasion was examined. T98G glioma cells grew well on these ECM components and invaded the reconstituted basement membrane. In contrast, A172 glioma cells showed growth inhibition on collagen types IV and V and Matrigel without invasion of the Matrigel. Gelatin zymography and enzyme immunoassays demonstrated that T98G glioma cells, but not A172 cells, secrete a large amount of matrix metalloproteinase-2 (MMP-2, 72 kD gelatinase/type IV collagenase = gelatinase A), and this was confirmed by immunoblotting and immunohistochemistry. Of the two different tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2), T98G cells produced only TIMP-1 during culture on Matrigel, whereas A172 cells secreted both. Although both human recombinant TIMP-1 and TIMP-2 stimulated T98G cell growth slightly on Matrigel, the in vitro invasiveness was significantly reduced by only recombinant TIMP-2. These results suggest that MMP-2 plays an important role in the ECM invasion of T98G human glioma cells in vitro.

Brain Neoplasms↗
PubMed1996

Changes in serum levels of metalloproteinases and their inhibitors by treatment of chronic hepatitis C with interferon.

We treated 18 patients with chronic hepatitis C by recombinant interferon-alpha (6 MIU for 24 weeks). In seven patients, serum aminotransferase levels declined to normal (responders). To evaluate the effect of interferon on matrix metalloproteinases (MMPs) and their inhibitors, namely tissue inhibitors of metalloproteinases (TIMPs), the serum levels of these enzymes were determined by enzyme immunoassay (EIA) using a specific monoclonal antibody. In responders, there was a tendency, but not a significant one, towards either an increase in serum MMP 1 levels or a decrease in serum TIMP 1 levels. In contrast, in nonresponders, both a significant decrease in MMP 1 and MMP 3 and a significant increase in TIMP 1 were observed. The number of cases of either increase in serum MMP levels or decreased in serum TIMP levels was significantly larger in responders than in nonresponders. Furthermore, the ratio of MMP 1 to TIMP 1 significantly increased in responders, suggesting that the balance between matrix formation and degradation in hepatic fibrosis tended to move toward degradation. These data indicate that interferon may exert a beneficial effect on hepatic fibrosis in parallel with improvement of aminotransferase activity.

Adult↗
PubMed1996

Elevated plasma levels of matrix metalloproteinase-9 (92-kd type IV collagenase/gelatinase B) in hepatocellular carcinoma.

BACKGROUND: Matrix metalloproteinase 9 (MMP-9), a 92-kd gelatinase/type IV collagenase, has been implicated as playing an important role in cancer invasion and metastasis. A previous study showed that serum type IV collagenase activity correlated with metastasis by hepatocellular carcinoma (HCC). The aims of this study were to determine the plasma levels of immunoreactive MMP-9 in patients with HCC and to compare the levels with the clinical features including vascular invasion. PATIENTS AND METHODS: This study included 100 patients with HCC, 21 patients with chronic hepatitis (CH), 24 patients with liver cirrhosis (LC), and 138 healthy control subjects. Plasma MMP-9 levels were measured with a specific one-step sandwich enzyme immunoassay. RESULTS: Plasma MMP-9 levels in HCC (62 [33 to 130 ng/mL] median [25%, 75%], 13 to 660 ng/mL, minimum, maximum) were significantly elevated compared with those in normal controls (36 [25 to 45], range, 2.8-70 ng/mL), in CH (28 [18 to 30], 13 to 66 ng/mL) and in LC (35 [26 to 58], 16 to 86 ng/mL) (P < .0000001; P = .0000003; and P = .00205, respectively). When the cut-off level was defined as 60 ng/mL from a receiver operating characteristic curve, plasma MMP-9 concentrations had a sensitivity of 53% and a specificity of 89% for the detection of HCC from CH and LC. The levels were significantly higher in HCC patients with macroscopic portal venous invasion (79 [36 to 160], 15-660 ng/mL) than those without the invasion (44 [27 to 80], 13 to 210 ng/mL) (P = .00726). Plasma MMP-9 levels in patients with HCC were not correlated with tumor number, size, volume, or serum alpha-fetoprotein levels. CONCLUSIONS: The present data suggest that plasma MMP-9 levels can be a candidate for a novel marker for HCC. The levels appear to reflect its potential and ongoing activity of vascular invasion. A long-term follow-up of the patients will be necessary to determine whether increased plasma MMP-9 levels are predictive of more invasive and metastatic HCC.

Adult↗
PubMed1996

Effect of prostaglandins on cultured porcine iris sphincter muscle cells.

Porcine iris sphincter muscle strips contracted in response to carbachol. The tissue contraction was inhibited by prostaglandin (PG) E2 but not by PGF2 alpha. In order to investigate the effect of PGs on the iris cells, the porcine sphincter muscle cells were grown in culture to a confluence and characterized. Using the secondary culture of cells, the effect of PGs on carbachol-induced cell contraction was investigated. Both PGE2 and PGF2 alpha at 100 microM blocked cell contraction completely. The concentration required to inhibit 50% of the maximum contraction in 15 minutes was 10(-6) M for PGE2 and 10(-6)-10(-7) M for PGF2 alpha. Using PGE2 receptor subtype agonists (EP2 agonist, 11-deoxy-16, 16 dimethyl PGE2 and EP3 agonist, sulprostone), PGE2 receptor involved in the inhibition of carbachol-induced contraction was identified to be of the EP2 subtype. In support of this characterization, the addition of PGE2 to cultured porcine sphincter muscle cells increased intracellular cAMP level. The discrepancy in PGF2 alpha effect on carbachol-induced sphincter muscle contraction between iris tissue strips and cultured cells suggests that nonmuscular cells may be involved in the modulation of the PGF2 alpha effect on sphincter muscle cells in vivo.

Animals↗
PubMed1996

Influence of paternal (252) Cf neutron exposure on abnormal sperm, embryonal lethality, and liver tumorigenesis in the F(1) offspring of mice.

Experiments were conducted to determine whether neutron-induced genetic damage in parental germline cells can lead to development of cancer in the offspring. Seven-week-old C3H male mice were irradiated with (252) Cf neutrons at a dose of 0, 50, 100, or 200 cGy. Two weeks or three months after irradiation, the male mice were mated with virgin 9-week-old C57BL females. Two weeks after irradiation, the irradiated male mice showed an increased incidence of sperm abnormalities, which led to embryo lethalities in a dose-dependent manner when they were mated with unirradiated female mice. Furthermore, liver tumors in male offspring of male mice in the 50 cGy group were significantly increased in 19 of 44 (43.2%) animals, in clear contrast to the unirradiated group (1 of 31; 3.2%) (P < 0.01). In the 100 cGy group, 6 of 39 (15%) mice had lesions. At 3 months after irradiation abnormal sperm and embryonal lethality were not significantly increased. The incidences of liver tumors in male offspring from the 50 cGy, 100 and 200 cGy groups were 6 of 20 (30%), 5 of 22 (23%) and 1 of 19 (5%), respectively, which are not significantly increased compared with the control. It is concluded that increased hepatic tumor risk in the F(1) generation may be caused by genetic transmission of hepatoma-associated trait(s) induced by (252) Cf neutron irradiation.

Animals↗
PubMed1996

Gastric tumorigenicity of 1,2-dimethylhydrazine on the background of gastric intestinal metaplasia induced by X-irradiation in CD (SD) rats.

Five-week-old male CD (SD) rats were X-irradiated with a total of 20 Gy in 2 equal fractions with a 3-day interval. After the second irradiation, rats were fed normal diet supplemented with 1% sodium chloride, which is known to increase intestinal metaplasia. 1,2-Dimethylhydrazine (DMH) solution was injected i.m. into the back musculature at a dose of 20 mg/kg body weight weekly for 10 weeks, beginning 20 weeks after the final irradiation. Twelve months after the initial carcinogen treatment, gastric tumors in the glandular stomach were observed in 2 (3 lesions) of 30 animals in the X-irradiated and DMH-treated group fed diet supplemented with 1% sodium chloride. No gastric tumors were observed in the group which excluded X-irradiation from the experimental protocol.

1,2-Dimethylhydrazine↗
PubMed1996

Production of matrix metalloproteinases and tissue inhibitors of metalloproteinases in human breast carcinomas.

We examined production and tissue localization of matrix metalloproteinase (MMP)-1 (tissue collagenase), MMP-2 (gelatinase A), MMP-3 (stromelysin-1), MMP-9 (gelatinase B), tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 in human breast carcinomas. In more than half of the cases, MMP-1, MMP-2, MMP-9, TIMP-1 and TIMP-2 were immunolocalized in carcinoma cells and MMP-2 was on the carcinoma cell membranes as well, whereas MMP-3 was positively stained in less than 15% of the cases. MMP-1 staining in carcinoma cells was significantly higher in scirrhous carcinoma than in other types of carcinoma. MMP-9 expression was remarkably higher in the carcinoma cases with lymphnode metastasis than in the non-metastatic cases. MMP-3 was mainly expressed in T-lymphocytes infiltrated in the tumor stroma. Stromal fibroblasts were positive for all these MMPs except for MMP-3. The TIMP-1 levels released into the culture media by carcinoma tissues were significantly lower than those by fibroadenoma tissues, although there were no significant differences in the levels of MMP-1, MMP-2, MMP-9 and TIMP-2. Gelatin zymographical analyses showed that the activation rate of the zymogen of MMP-2 (proMMP-2) is significantly higher in the more advanced carcinoma group with lymphnode metastasis than in the metastasis-negative and fibroadenoma groups. These data indicate that MMP-1, MMP-2 and MMP-9 are highly expressed in human breast carcinoma tissue and suggest that activation of proMMP-2 may be an indicator of lymphnode metastasis of the breast carcinoma.

Breast Neoplasms↗
PubMed1996

Blockade of the estrogen induced increase in progesterone receptor caused by propylthiouracil, an anti-thyroid drug, in a transplantable pituitary tumor in rats.

It is well known that estrogen (E2) induces progesterone receptor (PR) in the uterus and the mammary gland. In MtT/F84, a pituitary tumor, which was established in our laboratory and has been maintained with in vivo passages, we investigated the PR regulation by E2 in relation to the host's thyroidal status. The PR level in the tumor had increased five fold 48 h after an E2 injection. When the host rats were treated with propylthiouracil (PTU), an anti-thyroid drug, the induction of PR after an E2 injection was completely blocked. This result is consistent with our previous findings indicating that E2 responsiveness in the tumor may be under the control of thyroid hormones. The estrogen receptor (ER) level in the tumor treated with PTU was 15% of the control. This low ER level may account for the blocking of PR induction after an E2 injection. When the host animals were continuously treated with various doses of E2, the PR level in the tumor rose in correlation with the E2 doses. PTU administration, however, did not prevent long term induction of PR by continuous E2 treatment. Our findings suggest that PTU lower the ER level and suppresses the short term estrogenic actions such as PR induction after an E2 injection.

Animals↗
PubMed1996

Intraluminal tumor of the common bile duct as a metastasis of renal cell carcinoma.

A 57-year-old woman was admitted for evaluation of liver dysfunction. A physical examination revealed jaundice and a left abdominal mass, which was diagnosed as being a large renal tumor. Cholangiography showed a smooth filling defect 1 cm in diameter at the common bile duct. Left nephrectomy, and resection of the common bile duct were performed. The pathological diagnosis was metastasis of the common bile duct wall resulting from renal cell carcinoma. Metastatic common bile duct tumors are extremely rare. However, it is important to consider that this is one of the causes of obstructive jaundice.

Carcinoma, Renal Cell↗
PubMed1996

Clinical usefulness of serum cytokeratin 19 fragment as a tumor marker for lung cancer.

Serum soluble cytokeratin 19 fragment (CYFRA) levels were measured in 251 patients with lung cancer and 139 patients with benign lung diseases to determine the clinical usefulness of CYFRA level determination in the diagnosis and monitoring of lung cancer. Serum levels of CYFRA were measured by a 2-step sandwich ELISA method. When the cut-off value was defined as 3.5 ng/ml, which was associated with a specificity of 95% for benign lung diseases, CYFRA had a high sensitivity (53%) in all patients with lung cancer. Both the serum level of CYFRA and its sensitivity increased significantly with the increase in clinical stage. A comparison of areas under receiver operating characteristic curves showed that CYFRA had the most power of discrimination in the diagnosis of lung cancer among markers including carcinoembryonic antigen, squamous cell carcinoma antigen, carbohydrate antigen 19-9, and neuron-specific enolase. A good correlation was found between serial changes in serum CYFRA levels during therapy and clinical responses for 18 patients who underwent chemotherapy and/or radiotherapy. Our findings suggest that CYFRA may be a marker of choice for screening and monitoring of lung cancer, particularly squamous cell carcinoma.

Adenocarcinoma↗
PubMed1996

[Experience of 28 deliveries in 21 kidney transplant recipients].

BACKGROUND: Risk factors to induce graft dysfunction during pregnancy in kidney transplant recipients were studied. METHODS: A total of 28 deliveries from 21 female kidney transplant recipients were analyzed. RESULTS: All recipients were maintained on either azathioprine-based (n = 17) or cyclosporine-based (n = 11) immunosuppressive regimens. Graft dysfunction (creatinine clearance < 40 ml/min) occurred in 8 cases (8 patients) during pregnancy. No acute rejection, however, could be observed. In a case-controlled study comparing a group with graft dysfunction vs. a group with good graft function, there were significantly differences in the incidence of the cases with pre-existing hypertension (62.5% vs. 10.0%), the age of the grafted kidney (58.1 vs 47.6 year), the maternal anemia (Hb: 10.3 vs. 11.8 g/dl) and the creatinine level (1.4 vs. 1.0 mg/dl) at the first trimester. These findings suggested that poorer graft function had been underlying before pregnancy and that additional loading of the pregnancy reduced further graft function, while the deterioration would be recovered after delivery in all cases except one case. CONCLUSION: Risk factors to induce graft dysfunction during pregnancy are as follows. 1) high age of the grafted kidney (> 50 year), 2) pre-existing hypertension, 3) maternal anemia (Hb: < 11 g/dl) and 4) high creatinine level (> 1.3 mg/dl) at the first trimester.

Adult↗
PubMed1996

Matrix metalloproteinase 9 (gelatinase B) is expressed in multinucleated giant cells of human giant cell tumor of bone and is associated with vascular invasion.

Human giant cell tumor (GCT) consists of multinucleated giant cells and mononuclear stromal cells, and is characterized by frequent vascular invasion without distant metastases. To study the role of matrix metalloproteinases (MMPs) in the vascular invasion, we examined production of MMP-1 (tissue collagenase), -2 (gelatinase A), -3 (stromelysin-1), -9 (gelatinase B), and tissue inhibitors of metalloproteinases (TIMP-1 and -2) in GCT. MMP-9 was highly and predominantly expressed in giant cells by both immunohistochemistry and in situ hybridization. Expression of other MMPs was also observed in some cases but was inconstant. Sandwich enzyme immunoassays demonstrated that MMP-9 is the predominant MMP secreted by GCT. There was a definite imbalance between the amounts of MMP-9 and those of TIMPs in the culture media of GCT, leading to detectable gelatinolytic activity in an assay using 14C-gelatin. Gelatin zymography demonstrated the main activity at about 90 kd, which was identified as the zymogen of MMP-9 by immunoblotting. Immunohistochemistry for type IV collagen and laminin, major basement membrane components, showed that disappearance of the proteins is closely associated with MMP-9-positive giant cells. These results indicate the production of MMP-9 by multinucleated giant cells and suggest that the metalloproteinase may contribute to proteolysis associated with vascular invasion and local bone resorption in human GCT.

Adolescent↗
PubMed1996

[A case of primary intracranial malignant fibrous histiocytoma associated with peritumoral hemorrhage].

Malignant fibrous histiocytoma (MFH) is common among the soft-tissue sarcoma and especially occurs in the retroperitoneum and the four extremities. However primary intracranial MFH is an extremely rare occurrence. A case with primary intracranial MFH associated with peritumoral hemorrhage is reported. A 81-year-old woman was admitted to our department with impaired consciousness and left hemiparesis. On admission, she was drowsy. Computed tomography (CT) scans revealed a low density mass lesion of 4.5 x 3.5 x 6.0cm in diameter, which was surrounded by a high density area suggesting hematoma, in the right frontal lobe adjacent to the falx cerebri. The low density mass was homogeneously enhanced by contrast medium. Magnetic resonance imaging revealed that the mass was hypointense on T1 weighted image and hyperintense on T2 weighted image. After administration of Gd-DTPA, the mass was homogeneously enhanced and the falx cerebri was also enhanced at the site of attachment. Right carotid angiogram showed a tumor stain fed by the anterior cerebral artery. On operation, bleeding was encountered between the tumor and the falx cerebri on opening the dura mater. Hematoma existed between the tumor and the normal cerebral parenchyma. The tumor was sharply demarcated and didn't invade the normal cerebral parenchyma or the falx cerebri, so we considered that the tumor originated from the meninges. Histologically, pleomorphic spindle cells in atypical storiform pattern were observed. Multinucleated giant cells were also seen. This case suggested to us that primary intracranial MFH may be associated with intracranial hemorrhage.

Aged↗