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J Murakami

Publications and source records attributed to J Murakami.

At least 55 records · Page 3Linked to original sources
PubMed1998

SPARC from corneal epithelial cells modulates collagen contraction by keratocytes.

PURPOSE: Contraction of the scar tissue during corneal wound healing changes the shape of the cornea and corneal refraction. In a previous study, it was found that corneal epithelial cells secrete the factor that stimulates collagen gel contraction by keratocytes in vitro. The purpose of the present study was to purify and identify the contraction-stimulating factor derived from corneal epithelial cells. METHODS: The cultured medium of rabbit corneal epithelial cells was collected and used as an epithelial cell-conditioned medium (ECCM). Subcultured rabbit keratocytes were embedded in a collagen gel, and collagen gel contraction was investigated. The contraction-stimulating factor in the ECCM was purified through acetone precipitation, affinity chromatography (heparin Sepharose), gel filtration, and reversed-phase chromatography. The amino acid sequence of a contraction-stimulating factor was analyzed. RESULTS: Collagen gel contraction by keratocytes was enhanced by the addition of ECCM in a dose-dependent manner. The amino acids sequence of the contraction-stimulating factor was homologous to a 32-kDa glycoprotein, a secreted protein that is acidic and rich in cysteine (SPARC). Western blot analysis confirmed that SPARC was contained in the ECCM. Collagen gel contraction by keratocytes was enhanced by the addition of purified SPARC in a dose-dependent manner. SPARC was found in the basal layer of the migrating epithelium and activated keratocytes adjacent to the wound 3 days and 1 week after perforating injury in rabbit corneas. CONCLUSIONS: Epithelial cells secrete SPARC, which modulates the contraction of scar tissue in the corneal stroma.

Animals↗
PubMed1997

Telomerase activity in ovarian tumors.

BACKGROUND: Shortening of telomeres occurs with each cell division and eventually results in cell death. The activity of telomerase, an enzyme that catalyzes telomere elongation, has been detected in germ cell lines and cancer cells, and has been detected in immortal cell lines but not in normal somatic cells. The relationship between telomerase expression and ovarian carcinogenesis was investigated. METHODS: Ovarian tissue was obtained from 41 women with ovarian tumors (10 benign, 6 borderline-malignant, and 25 malignant tumors) and 6 with uterine disease (2 with uterine myoma and 4 with uterine carcinoma). These specimens were analyzed for telomerase activity and telomere length by the telomeric repeat amplification protocol and Southern blot hybridization, respectively. RESULTS: Telomerase activity was detected in 23 of 25 malignant ovarian tumors (92%), in 1 of 6 borderline-malignant tumors (16.7%), and in 2 of 10 benign tumors (20%) (both of which were germ cell tumors). Weak telomerase activity was present in the cortex of normal ovaries from premenopausal women, and appeared to be attributable to follicles. Telomerase activity in malignant and poorly differentiated tumors tended to be higher than that in other tumors. Terminal restriction fragment length ranged between 8 and 13 kilobase pairs (kbp) for normal ovaries, and was <8 kbp in 1 of 6 malignant Stage I tumors (16.7%), 1 of 2 Stage II tumors (50%), and 9 of 17 Stage III tumors (52.9%). CONCLUSIONS: Telomerase activity may be a useful marker for the diagnosis of ovarian tumors.

Adult↗
PubMed1997

T-686, a novel inhibitor of plasminogen activator inhibitor-1, inhibits thrombosis without impairment of hemostasis in rats.

The aim of this study was to evaluate the antithrombotic potential of T-686 ((3E,4E)-3-benzylidene-4-(3,4,5-trimethoxy-benzylidene)-pyrr olidine-2,5-dione), a novel inhibitor of plasminogen activator inhibitor-1 (PAI-1), in rat thrombosis models. T-686 (0.1-100 mg/kg per day, p.o.) dose dependently decreased the weight of venous thrombi induced by a combination of stasis and hypercoagulability. The antithrombotic effect was enhanced by repeated administration of T-686. Warfarin (0.1 mg/kg per day for 3 days) also prevented thrombus formation. The antithrombotic action by warfarin was accompanied by prolongation of coagulation time, while no effect on coagulation time was observed in T-686-treated rats. T-686 lowered the activity of PAI-1 in plasma. In the arterio-venous shunt model, pretreatment with T-686 (10 mg/kg per day) or ticlopidine (100 mg/kg per day) for 8 days inhibited thrombus formation by 33% and 44%, respectively. T-686 had no effect on collagen-induced platelet aggregation ex vivo, while ticlopidine inhibited platelet aggregation. T-686 did not affect bleeding time at 10-100 times the antithrombotic dose, while warfarin dose dependently prolonged bleeding time at and around the antithrombotic dose. These results suggest that T-686 prevents thrombus formation in rats without impairment of hemostasis.

Animals↗
PubMed1997

Acute suppurative perithyroiditis: MR findings.

We report the MR findings in two cases of acute suppurative perithyroiditis. MR has the advantages over other imaging modalities of being able to distinguish areas of inflammation from adjacent normal tissue and of allowing imaging in planes which more accurately demonstrate the extent of the lesion. MR imaging is one of the most useful methods to evaluate this entity.

Acute Disease↗
PubMed1997

Colour Doppler sonography of breast masses: a multiparameter analysis.

OBJECTIVE: To evaluate signals from breast lesions on both colour and spectral Doppler US, and to correlate findings with angiographic and histopathological features including microvessel density. MATERIALS AND METHODS: One hundred and sixteen breast lesions in 113 patients were evaluated with colour Doppler ultrasonography. Subjective and semi-quantitative assessment of colour signals as well as spectral Doppler analysis were performed and compared. Comparison of colour Doppler features with angiographic and histopathological findings were also carried out. RESULTS: Subjective evaluation revealed that colour signals were more commonly found in malignant (89%) than benign (56%) lesions. Malignant lesions demonstrated a more elaborate vascular network (51%) compared to 12.5% in benign lesions. Spectral Doppler analysis revealed slightly higher specificity values for the pulsatility and resistivity indices, respectively, but lower sensitivity and accuracy values compared to qualitative assessment. Colour Doppler patterns corresponded well with angiograhic images, however, the correlation between colour Doppler parameters and microvessel density was not significant. CONCLUSION: Despite the increased examination time required, spectral analysis does not appear to contribute significantly to the differentiation between malignant and benign breast tumours. Features such as the density, pattern and predominant site of colour signals may be more useful for the evaluation of breast lesions on colour Doppler imaging.

Adolescent↗
PubMed1997

Primary non-Hodgkin lymphoma of the sinonasal cavities: correlation of CT evaluation with clinical outcome.

PURPOSE: To determine retrospectively the primary site of origin of sinonasal lymphomas with computed tomography (CT) and correlate the CT findings with histologic phenotype and clinical outcome. MATERIALS AND METHODS: In 24 patients with stage I and II non-Hodgkin lymphomas of the sinonasal cavities, the CT appearances and clinical data were reviewed retrospectively. RESULTS: The sites of primary tumor determined at CT were the nasal cavity in 13 patients, the ethmoidal sinus in three patients, and the maxillary sinus in eight patients. B-cell lymphomas were found mainly in the maxillary sinus, while T-cell lymphomas were found in the nasal cavity and ethmoidal sinus (P < .005). The 5-year survival rates in relation to the primary site of the tumor were 64% for the nasal cavity, 50% for the ethmoidal sinus, and 100% for the maxillary sinus (P = .26). CONCLUSION: Patients with B-cell primary lymphoma of the maxillary sinus tended to have a good prognosis in contrast to those with T-cell lymphomas that originated from midline structures. The primary site determined at CT appears to be correlated with the histologic phenotype and clinical outcome.

Ethmoid Sinus↗
PubMed1997

MRI findings in the liver in biliary atresia patients after the Kasai operation.

To evaluate liver function in biliary atresia (BA) patients after the Kasai operation, magnetic resonance imaging (MRI) was carried out 28 times in 19 BA patients. Sixteen of these were divided into three groups on the basis of the serum level of total bilirubin (t-bil), glutamic pyruvic transaminase (GPT) and gamma-glutamyltransferase (gamma-GTP) in the postoperative follow-up period (2-11 years). In group 1 (n = 7) the t-bil was continuously kept under 1 mg/100 ml. In group 2 (n = 4) the t-bil was continuously kept under 1 mg/100 ml, but GPT and gamma-GTP remained high (GPT > 100 IU/liter, gamma-GTP > 200 IU/ liter) for more than 2 years. In group 3 (n = 5) an increase in the t-bil level reappeared (1-2 mg/100 ml; n = 4, > 2 mg/100 ml; n = 1). The differences between MRI finding in the 3 groups, and the correlation between MRI findings and laboratory data (t-bil, cholinesterase; ChE, GPT and gamma-GTP), which were taken around the time of MRI examinations, were studied. The results were as follows: (1) All 19 patients had normal or high signal areas of various sizes on T1 weighted images (WI). (2) Eighteen of 19 patients had high signal areas of various sizes on T2 WI in the portal system areas and/or liver parenchyma, and these areas were enhanced by gadolinium-DTPA in about half of the patients. (3) Ten of 16 patients had atrophic change over one liver lobe. (4) MRI findings for group 1 and the other groups were significantly different, and MRI findings, except for atrophic change, were correlated with the increase or decrease in laboratory data taken around the time of MRI examinations (p < 0.05). These results indicate that a normal or high signal area on T1 WI shows functional tissue, and that a high signal area on T2 WI shows tissue damaged by inflammation and/or progressive fibrosis. MRI is useful for evaluating liver function, especially in terms of morphological features, in BA patients after the Kasai operation, and will be one method for establishing their prognosis.

Alanine Transaminase↗
PubMed1997

[Intrapulmonary hematoma diagnosed by magnetic resonance imaging].

We report a case of intrapulmonary hematoma in which magnetic resonance imaging was useful in establishing the diagnosis. A 53-year-old man had bronchial asthma that was well controlled with inhaled beclomethasone dipropionate and salbutamol, and with oral theophylline. A spherical mass was found in the right lower lung field on a chest radiograph taken during a regular physical examination. A CT scan showed a well circumscribed spherical mass, which was attached to an intrapulmonary bullae. Magnetic resonance imaging showed a well-circumscribed mass in the superior segment of the right lower lobe. On a T1-weighted image the mass was hyperintense and had a higher-intensity rim. On a T2-weighted image the mass was hyperintense and had some hypointense areas. We therefore diagnosed intrapulmonary hematoma. Chest radiography 6 months later revealed a substantial decrease in the size of the mass, which supported the diagnosis. As in this case, intrapulmonary hematoma can be difficult to diagnose because of the lack of a history of injury and because of the slow regression. In this case, magnetic resonance imaging was useful in making the diagnosis.

Hematoma↗
PubMed1997

[A case of 47XYY syndrome presenting with male infertility].

A 32-year-old man was referred to our hospital for primary infertility of a 4.5-year duration. Neither character nor intelligence disorders were observed. Bilateral testes measured 16 ml each. Sperm density was 0-0.1 x 10(6)/ml on 3 separate occasions. Endocrine examinations were all within normal limits. Maturation arrest was found on testicular biopsy. Karyotyping showed 47, XYY inversion. Polymerase chain reaction revealed no deletion of the azoospermic factor (AZF) gene on the Y chromosome. This is the 6th case reported in the Japanese literature of the 47XYY syndrome presenting with male infertility.

Adult↗
PubMed1997

Protective effect of T-686, an inhibitor of plasminogen activator inhibitor-1 production, against the lethal effect of lipopolysaccharide in mice.

We have examined the effects of an inhibitor of plasminogen activator inhibitor-1 (PAI-1) production, (3E,4E)-3-benzylidene-4-(3,4,5-trimethoxy-benzylidene)pyrrol idine-2,5-dione (T-686), on lipopolysaccharide (LPS)-induced death in mice. Oral administration of T-686 (10 and 100 mg/kg/day) for 8 days prior to the LPS injection (35 mg/kg, i.v.) protected mice from the lethal effect of LPS in a dose-dependent fashion. Moreover, treatment with 100 mg/kg T-686 attenuated the increase in plasma PAI-1 activity and the decrease in AT-III activity induced by LPS. We conclude that T-686 can reduce the mortality of mice induced by LPS, which seems to be partially correlated with both hypercoagulation and hypofibrinolysis.

Angiotensin III↗
PubMed1997

Availability of nasal mask BiPAP systems for the treatment of respiratory failure after cardiovascular surgery.

BACKGROUND: The availability of nasal mask bi-level positive airway pressure (BiPAP) support in managing respiratory failure following cardiovascular surgery was studied. MATERIALS AND METHODS: BiPAP support was used for eight patients requiring postoperative prolonged respiratory support of 72 hours or longer. Their mean age was 65 years of age and the mean periods of postoperative endotracheal intubation was 12+/-5 days. BiPAP support was removed within 48 hours in six out of eight patients. Reintubation of an endotracheal tube was not necessary in all eight patients after the BiPAP treatment. RESULTS: The respiratory rates during the BiPAP management remained unchanged. The values of the respiratory index significantly (p<0.01) improved after BiPAP management (1.5+/-0.2 --> 0.9+/-0.2). A-aDO2 and Qs/Qt decreased (p<0.1) after the BiPAP management. There were no significant differences in central venous pressure and circulatory states during BiPAP support. CONCLUSIONS: In conclusions, BiPAP support is a noninvasive management technique for postoperative respiratory failure and may also prevent prolonged endotracheal intubation.

Aged↗
PubMed1996

Primary B-cell lymphoma of the breast in patient with smoldering type adult T-cell lymphoma.

We report a patient with primary B-cell lymphoma of the breast complicated by smoldering type adult T-cell leukaemia (ATL). A 52-year-old Japanese woman complained of a rapidly enlarging lump in her right breast. She had been diagnosed to have smoldering type ATL since the age of 49. Aspiration cytology and subsequent excisional biopsy revealed B-cell type lymphoma of the breast. A gallium-scintigram showed abnormal accumulation in the bilateral breasts. Radiology was adopted because the lesion was localized only in the breasts and associated with smoldering type ATL. The lesions disappeared after the treatment.

Breast Neoplasms↗
PubMed1996

Inhibitory effect of a new butadiene derivative on the production of plasminogen activator inhibitor-1 in cultured bovine endothelial cells.

Tissue-type plasminogen activator (t-PA) and its physiological inhibitor, plasminogen activator inhibitor-1 (PAI-1), are known to be synthesized by vascular endothelial cells and to play important roles in regulating the fibrinolytic activity of plasma. We found that a new butadiene derivative, (3E, 4E)-3-benzylidene-4-(3,4,5-trimethoxybenzylidene)pyrrolidine -2,5-dione (T-686), inhibits PAI-1 production without affecting plasminogen activator (PA) synthesis in cultured bovine endothelial cells. T-686 (1-10 microM) dose-dependently decreased the accumulation of PAI-1 in conditioned medium from the treated cells and elevated PA activity in the conditioned medium. Analysis of the conditioned medium by the zymography technique indicated that T-686 decreased the activities of PAI-1 with an M(r) of 55,000 and t-PA/PAI-1 complex with an M(r) of 99,000. Furthermore, T-686 attenuated the augmentation of PAI-1 antigen induced by lipopolysaccharide in the conditioned medium. The decrease of PAI-1 antigen was in parallel with the reduction of the PAI-1 mRNA level (Northern blots). These results suggest that T-686 can promote net fibrinolytic activity through suppression of PAI-1 production without affecting PA elaboration in endothelial cells.

Animals↗
PubMed1996

Partial monosomy 10q and partial trisomy 9q with anal atresia due to maternal translocation: t(9;10)(q32;q26).

We report a case of a boy with a partial deletion of the long arm of chromosome 10 and partial duplication of the long arm of chromosome 9 due to maternal balanced translocation. The karyotype was 46,XY,-10, +der(10)t(9;10)(q32;q26)mat. Our patient had imperforate anus and as this finding is usually not observed in association with trisomy 9q, it suggests that partial monosomy of the long arm of chromosome 10 might be associated with anogenital anomalies.

Abnormalities, Multiple↗
PubMed1996

Breast lesions: correlation of contrast medium enhancement patterns on MR images with histopathologic findings and tumor angiogenesis.

PURPOSE: To compare qualitative and quantitative magnetic resonance (MR) mammographic features of breast lesions with histopathologic findings, especially tumor angiogenesis. MATERIALS AND METHODS: Seventy-three patients (72 women, one man; aged 30-78 years; mean age, 51.0 years) with suspicious breast lesions underwent MR imaging. Noncontrast medium-enhanced localization imaging and then gadolinium-enhanced dynamic fast spoiled gradient-recalled-echo (SPGR) imaging were performed in all patients. In selected patients, subtraction fast SPGR images were obtained. The Pearson and Spearman correlation tests were used to determine the strength of the relationships between enhancement parameters and microvessel determinations. RESULTS: Time intensity curve type correlated with microvessel density grade (Spearman rank correlation test: r = .90, P < .001). The steepest slope of contrast medium uptake correlated with microvessel counts (Pearson correlation test; r = .83, P < .001). Peripheral enhancement in invasive carcinomas (n = 9) correlated with high peripheral and low central microvessel densities, which were associated with desmoplasia and/or necrosis. Internal septations (n = 2) were seen only in fibroadenomas. CONCLUSION: The density and distribution of microvessels may play major roles in the determination of the initial rate of contrast medium uptake and the heterogeneity of tumor enhancement.

Adult↗
PubMed1996

[Surgical repair of atrial septal defect and tricuspid regurgitation in a 79-year-old man: a case report].

A 79-year-old man with atrial septal defect (ASD) and tricuspid regurgitation was successfully operated upon. Preoperative examinations showed atrial fibrillation, moderate pulmonary hypertension and lung dysfunction. Direct closure of the ASD accompanying with tricuspid annuloplasty was performed. Postoperative administration of catecholamines continued for twenty-six days to maintain hemodynamics. An intratracheal tube was extubated two days after the operation. However, an additional respiratory support using a nasal continuous positive airway pressure method was required for six days. His postoperative physical activity has been improved with class I of the New York Heart Association classification. Surgical intervention may be the treatment of choice for aged patients over 70 years with an ASD.

Aged↗