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Biomedical subjects

M Maeyama

Publications and source records attributed to M Maeyama.

At least 19 recordsLinked to original sources
PubMed2006

Spreds, inhibitors of the Ras/ERK signal transduction, are dysregulated in human hepatocellular carcinoma and linked to the malignant phenotype of tumors.

Aberrant activation of the Ras/Raf-1/extracellular-regulated kinase (ERK) pathway has been shown to be involved in the progression of human hepatocellular carcinoma (HCC). However, the mechanism of dysregulation of ERK activation is poorly understood. Recently, we identified Sprouty-related protein with Ena/vasodilator-stimulated phosphoprotein homology-1 domain (Spred) as a physiological inhibitor of the Ras/Raf-1/ERK pathway. In this study, we found that the expression levels of Spred-1 and -2 in human HCC tissue were frequently decreased, comparing with those in adjacent non-tumorous tissue. Moreover, Spred expression levels in HCC tissue were inversely correlated with the incidence of tumor invasion and metastasis. Forced expression of Spred-1 inhibited HCC cell proliferation in vitro and in vivo, which was associated with reduced ERK activation. Spred-1 overexpression also reduced the secretion of matrix metalloproteinase-9 (MMP-9) and MMP-2, which play important roles in tumor invasion and metastasis. In addition, Spred-1 inhibited growth factor-mediated HCC cell motility. These data indicate that the reduction of Spred expression in HCC is one of the causes of the acquisition of malignant features. Thus, Spred could be not only a novel prognostic factor but also a new therapeutic target for human HCC.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Adduct of acetylene at sulfur in an oxygen- and sulfur-bridged open cubane cluster complex of tungsten.

Formation of a single carbon-sulfur bond is described. The reaction of incomplete cubane-type sulfur and oxygen-bridged isothiocyanato tungsten cluster [W3(mu3-S)(mu-O)(mu-S)2(NCS)9]5- (7) with acetylene affords [W3(mu3-S)(mu-O)(mu-S)(mu-SCH=CH2)(NCS)9]4- (8). The cluster 8 has been isolated as K0.5(Hpy)3.5[W3(mu3-S)(mu-O)(mu-S)(mu-SCH=CH2)(NCS)9] (8'), whose structure has been characterized by X-ray crystallography, electronic spectra, and 1H and 13C NMR spectroscopy. Crystal data of 8': triclinic system, space group P1, a = 14.465(5) A, b = 17.353(3) A, c = 10.202(2) A, alpha = 90.98(1) degrees, beta = 108.59(2) degrees, gamma = 98.13(2) degrees, V = 2397.6(10) A(3), Z = 2, D(c) = 2.096 g cm(-3), Dm = 2.08 g cm(-3), R (Rw) = 3.6 (5.5)% for 8786 reflections (I > 1.50 sigma(I)). The carbon-carbon distance is 1.27(1) A and is almost equidistant between ethylene (1.339 A) and acetylene (1.203 A). The electronic spectrum of 8' in 1.0 M HCl containing 1.5 M KSCN has a characteristic broad peak in the near-infrared region [lambda(max), nm (epsilon, M(-1) cm(-1)): 840 (650), 575 (1450)]. (1)H NMR and HH correlation spectroscopy (COSY) of 8' in CD3CN support the results of the X-ray structural analysis. The (1)H NMR spectrum shows three signals at 2.42 (1H, dd), 4.84 (1H, d, J = 8.8 Hz), and 4.89 (1H, d, J = 16.2 Hz) ppm due to the mu-SCH=CH2 moiety of 8'. The correlation spectrum shows spin couplings of the signal at 2.42 ppm with the signals at 4.84 and 4.89 ppm. The mechanism of the formation of 8 is suggested to proceed through an intermediate with acetylene bridging two of the sulfur atoms.

Journal Article↗
PubMed1993

[An outbreak of Pseudomonas sepsis associated with nosocomial infection in a pediatric ward].

A five-year old girl, diagnosed with fever of unknown origin (FUO), was transferred to our hospital due to a deterioration in her general condition. Pseudomonas cepacia (P. cepacia) was detected in her blood culture and she soon recovered after imipenem cilastatin (IPM/CS) administration. When the former hospital was informed of the results of her blood cultures, we learned that five other cases of FUO had occurred there within the previous two weeks in noncompromised children. Except for one case, Pseudomonas species was detected in their blood cultures. P. cepacia was found in one case, Pseudomonas aeruginosa (P. aeruginosa) was detected in two other cases, and both P. cepacia and P. aeruginosa were demonstrated in the other patient. Although the origin of the bacteria is unknown, it may have spread to the children through a contaminated liquid reservoir or medical devices.

Bacteremia↗
PubMed1990

Growth stimulation by androgens, glucocorticoids or fibroblast growth factors and the blocking of the stimulated growth by antibody against basic fibroblast growth factor in protein-free culture of Shionogi carcinoma 115 cells.

Shionogi carcinoma 115 (SC115) has been accepted for 20 years as an androgen-responsive mouse mammary tumor. We have established an androgen-dependent cloned cell line (SC-3) from a SC115 tumor. In a serum-free medium, testosterone (T) or fibroblast growth factors (FGFs) markedly stimulate the growth of SC-3 cells, and the T-induced growth was shown to be mediated through FGF-like peptide(s) in an autocrine mechanism. Since we used the serum-free culture including 0.1% bovine serum albumin (BSA), a partially serum-containing condition, putative roles of BSA- or serum-borne growth factors in growth stimulation of autocrine production of FGF-like peptide(s) could not be excluded. This paper reports findings performed in a protein-free medium including plating [Ham's F-12:MEM (1:1; v/v)]. In the protein-free culture, the growth of SC-3 cells was significantly stimulated by the addition of greater than or equal to 10(-10) M T (up to 20-fold), greater than or equal to 10(-7) M dexamethasone (Dex; up to 7-fold) or greater than or equal to 1 ng/ml basic (b) or acidic FGF (up to 10-fold); other various growth factors had no such effects. Furthermore, DNA synthesis of SC-3 cells induced by T, Dex or bFGF was similarly and markedly inhibited by bFGF neutralizing antibody IgG. Therefore, the present findings seem to demonstrate that androgens or high levels of glucocorticoids induce the production and secretion of FGF-like peptide(s) from SC-3 cells for their growth even in the absence of additional support by other factors.

Androgens↗
PubMed1987

Uterine papillary serous carcinoma with high levels of serum carcinoembryonic antigen. Response to combination chemotherapy.

A case of metastatic uterine papillary carcinoma with elevated serum carcinoembryonic antigen (CEA) is reported. The patient presented with ascites and pleural effusions and with a high level of CEA (258 ng/ml) 3 months after primary surgical resection and postoperative irradiation had been performed. Her complete response, although temporary, to two kinds of combination chemotherapy was evaluated using serial estimations of the serum CEA.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1986

Characterization of a vasopressor substance generated in human plasma by incubation.

Incubation of human plasma at 37 degrees C for several hours leads to the formation of a non-dialysable vasopressor substance termed the active pressor principle. Some of the chemical and physical natures of active pressor principle were investigated in anesthetized and ganglion blocked rats. It was found to have properties characteristic of protein. The substance was crudely purified to about 25-fold in alcoholic trichloroacetic acid solution after placing the plasma in a boiling water bath for 5 minutes ("active fraction"). After treatment of the vasoactive plasma or "active fraction" with Pronase, the pressor activity was almost abolished. The molecular weight of this fraction as determined by gel filtration was about 68,000. With addition of diisopropyl fluorophosphate before incubation of the plasma, no vasopressor substance was generated. After treatment of the rat with captopril, an angiotensin converting enzyme inhibitor, the pressor effect of incubated plasma was not inhibited. These findings suggest that a vasoactive protein, which is clearly different from renin, is generated during simple incubation of plasma, and that a serine protease is involved in the formation of this substance.

Angiotensin I↗
PubMed1986

Craniofacial defects associated with amniotic band syndrome: a case report.

A pathological study was made of a female infant with amniotic band syndrome. At birth, the 1450-g female infant was noted to have craniofacial defects such as anencephaly, cleft lip, severe nasal deformity and asymmetric microphthalmia. The fetal membrane was focally adhered to the scalp, and histological examinations revealed that the connecting area of the fetal head to the membrane resembled a serial architecture from keratinized squamous cells to amniotic layer without any inflammatory findings. These observations suggested that the etiology in the present case may be consistent with Torpin's mesodermic band theory.

Abnormalities, Multiple↗
PubMed1986

A case of clear cell adenocarcinoma of the uterine cervix in pregnancy.

An extremely rare case of clear cell adenocarcinoma of the uterine cervix in pregnancy is reported. The primary lesion was first found at 34 weeks of pregnancy in a 34-year-old patient, and was cytologically suspected to be malignant. At 39 weeks of pregnancy, the patient underwent abdominal cesarean section concomitantly with removal of huge right ovarian tumor (3050 g) and delivered a normal male baby weighing 3590 g. Histological findings for cone biopsy at 22 days postpartum revealed invasive adenocarcinoma, and abdominal radical hysterectomy and pelvic lymphoadenectomy were performed at 36 days postpartum. Microscopically, the tumor tissue was composed of clear and hobnail-type cells. It showed a considerable amount of PAS-positive diastase-labile glycogen but was only weakly positive for immunoperoxidase staining of carcinoembryonic antigen.

Adenocarcinoma↗
PubMed1986

Small cell carcinoma of the endometrium associated with adenosquamous carcinoma: a light and electron microscopic study.

This report describes a 64-year-old woman with a primary small cell carcinoma of the endometrium associated with adenosquamous carcinoma. The light microscopic features resembled those of small cell carcinoma of the lung and those of the uterine cervix, and foci of adenosquamous carcinoma lay scattered sparsely in the small cell carcinoma. Electron microscopy revealed cytoplasmic neurosecretory type granules. The neoplasm behaved in a very aggressive manner such that at 3 months after surgery a metastatic neoplasm appeared in the vagina. This case is a rare example of an endometrial carcinoma with differentiation toward endocrine as well as adeno and squamous cell carcinoma.

Adenocarcinoma↗
PubMed1986

Biochemical and immunohistochemical studies on carcinoembryonic antigen of ovarian mucinous and serous tumors.

The carcinoembryonic antigen (CEA) in the cyst fluid of ovarian mucinous and serous tumors was investigated. The molecular weight and antigenicity of the CEA from both ovarian tumors were very similar to those of colon cancer CEA as determined by SDS electrophoresis and double immunodiffusion on agar plates. In the cyst fluid of ovarian mucinous tumors, the amount of CEA was generally high and CEA of molecular weight (MW) 200,000 was increased. In contrast, in the cyst fluid of ovarian serous tumors, the CEA amount was low and CEA variants of MW 370,000 and 180,000 were present in addition to the main CEA of MW 200,000. Immunohistochemically, CEA was stained mainly in the intestinal type epithelium of ovarian mucinous tumors, and the CEA revealed a tendency to be stained more frequently and strongly with increasing degree of tumor malignancy. Thus, ovarian mucinous tumors (especially the intestinal type epithelium) produced large amounts of CEA which closely resembled colon cancer CEA, whereas ovarian serous tumors produced small amounts of CEA, including some CEA variants. In the study of ovarian epithelial tumors, CEA may be useful as a marker for the malignant transformation of ovarian mucinous tumors.

Carcinoembryonic Antigen↗
PubMed1986

The effects of A23187 and phorbol ester on the phosphorylation of proteins in rat anterior pituitary cells.

The effects of A23187 and 12-O-tetradecanoyl-phorbol-13-acetate (TPA) on the phosphorylation of proteins in normal rat anterior pituitary cells were compared. A23187 rapidly activated the phosphorylation of at least 5 proteins (45, 47, 53, 54 and 58 kDa), which reached the maximal level in 2-10 min, and decreased gradually thereafter. In contrast, TPA activated the phosphorylation of at least 6 proteins (45, 62, 64, 72, 76 and 82 kDa), which were mostly distinguished from those activated by A23187. TPA-induced response was elicited more slowly, reached a plateau after about 10 min, and was sustained thereafter. These results suggest that the protein phosphorylation stimulated by A23187 and TPA is conducted by different mechanisms.

Animals↗
PubMed1986

Eccrine adenocarcinoma of the vulva producing isolated alpha-subunit of glycoprotein hormones.

A rare case of adenocarcinoma of the sweat glands of the vulva producing isolated alpha-subunit of glycoprotein hormones is reported. By an immunohistochemical method, eccrine gland adenocarcinoma tissues obtained from the right vulva and from its metastatic lesion in the right subclavicular lymph nodes were found to react with human chorionic gonadotropin (hCG), alpha-hCG but not beta-hCG. The concentrations of alpha-subunit in the serum and urine were markedly elevated to 6000 ng/mL and 55,000 ng/mL, respectively, just before the death of the patient.

Adenocarcinoma↗
PubMed1986

Inguinal sweat gland carcinoma with choriocarcinomatous differentiation.

An inguinal sweat gland carcinoma is described including the unusual occurrence of alpha hCG. The alpha hCG was demonstrated in the tumor presenting choriocarcinomatous differentiation and undifferentiated polygonal cells in ordinary tumor nests. beta hCG and SP-1 were weakly and sporadically demonstrated in a small area of the tumor presenting choriocarcinomatous differentiation. On the other hand, hPL and histochemical reaction of placental type alkaline phosphatase were not observed in the choriocarcinomatous and undifferentiated tumor cells. CEA was observed in both ordinary sweat gland carcinoma nests and choriocarcinomatous differentiated regions. In the ordinary tumor nests, enzyme histochemical reactions of phosphorylase and SDH were positive. And S 100 protein was sporadically demonstrated. In spite of chemotherapy and radiotherapy, the patient died after a short duration of the disease.

Aged↗
PubMed1986

Pseudomyxoma peritonei: effect of chronic continuous immunotherapy with a streptococcal preparation, OK-432 after surgery.

Three cases of pseudomyxoma peritonei with ovarian neoplasma were treated by adjunctive immunotherapy with OK-432 after surgery. In 2 of the 3 cases, the periods of intramuscular injection of OK-432 were 11 and 16 months, respectively, and the 2 patients remain clinically free from evidence of disease, 7 and 6 years after surgery. The third patient is still undergoing treatment, with no evidence of recurrence at 4 months after surgery. These results, although for a small number of patients, clearly suggest that adjunctive immunotherapy with OK-432 may be suitable for treating pseudomyxoma peritonei of ovarian tumor origin.

Aged↗