Biomedical subjects

E Miyazaki

Publications and source records attributed to E Miyazaki.

At least 55 records · Page 3Linked to original sources

PubMed2000

Antenatal dexamethasone administration inhibits smooth-muscle-cell DNA synthesis in pulmonary-arterial media in nitrofen-induced congenital diaphragmatic hernia in rats.

The aim of this study was to investigate the effect of antenatal glucocorticoid therapy on smooth-muscle-cell (SMC) DNA synthesis in the pulmonary arteries (PA) in a nitrofen-induced congenital diaphragmatic hernia (CDH) rat model following nitrofen administration on day 9.5 of gestation. Antenatal dexamethasone (DEX) was given intraperitoneally on days 18.5 and 19.5 of gestation. Bromodeoxyuridine (BrdU) was injected via a jugular vein into the dam 1 h before the fetuses were killed by cesarean section at term. The fetuses were divided into three groups: group I (n = 10): normal controls; group II (n = 10): nitrofen-induced CDH; group III (n = 10): nitrofen-induced CDH with antenatal DEX treatment. Immunostaining of the lungs with anti-BrdU antibody was obtained by a standard avidin-biotin complex method. The number of immunopositive cells in the PA media and adventitia were counted using an image analyzer and analyzed statistically. The number of BrdU-immunopositive cells in the media was significantly increased in group II (16.83 +/- 3.01) compared to groups I (9.16 +/- 2.20) and III (6.83 +/- 1.70) (P < 0.01). There was no significant difference between groups I and III. The number of BrdU-immunopositive cells in the adventitia was not significantly different between the three groups. Antenatal DEX treatment inhibits SMC DNA synthesis in PA media in CDH lungs. This may be a possible mechanism by which antenatal DEX prevents structural PA changes in nitrofen-induced CDH in rats.

Animals↗

PubMed2000

Expression of UDP-GalNAc: polypeptide N-acetylgalactosaminyltransferase isozymes T1 and T2 in human colorectal cancer.

Uridine diphosphate (UDP)-GalNAc: polypeptide N-acetylgalactosaminyltransferase (GalNAc transferase) catalyzes the initial step in mucin type O-glycosylation, and its expression has been assumed to be altered between normal epithelial cells and cancer cells. We studied the alteration of GalNAc transferase expression during the carcinogenesis of human colorectal epithelial cells. We produced polyclonal antibodies against synthetic polypeptides with specific sequence to two GalNAc transferase isozymes, T1 and T2. Surgically resected specimens from 50 patients with colorectal cancer were immunohistochemically stained, and the staining grade (percentage of positively stained cells) was compared between cancer and its normal counterpart in the same specimen. Significant signals for both T1 and T2 expression were seen in the supranuclear region of normal and cancer cells, indicating the subcellular localization of the enzymes in the Golgi apparatus. The prevalence of positive staining for T1 and T2 expression in colorectal cancer was significantly higher than that in normal epithelium (P < 0.05). However, the difference in staining grades between cancer and normal tissues varied in each patient. These results indicate that there is variability in the expression patterns of GalNAc transferase isozymes in normal and cancerous cells colorectal among individuals.

Adenocarcinoma↗

PubMed2000

Appearance of denuded hepatic stellate cells and their subsequent myofibroblast-like transformation during the early stage of biliary fibrosis in the rat.

To investigate the early in vivo response of hepatic stellate cells in biliary fibrosis, we examined rat livers during the first 7 days after bile duct ligation using light microscopy, immunohistochemistry, electron microscopy, and immunoelectron microscopy. At day 1 after bile duct ligation, alpha-smooth muscle actin-positive fibroblasts appeared and then increased in number around the proliferating bile ductules. With time, the destruction of the external limiting plate became accentuated because of the invasion of the proliferating bile ductules and periductural fibrosis. At day 7, stromal cells containing fat droplets appeared in the fibrous tissue adjacent to the periportal parenchyma; these are termed denuded hepatic stellate cells. In the fibrous tissue disconnected from the liver parenchyma, the denuded hepatic stellate cells were replaced by myofibroblast-like cells. Meanwhile, the expression of transforming growth factor-beta1 on biliary epithelial cells increased. These results indicate the dual origin of myofibroblasts in experimental biliary fibrosis, the periductural and periductal fibroblasts in the initial stage, and the denuded hepatic stellate cells in the subsequent stage. These two types of stromal cells may undergo myofibroblastic transformation by the transforming growth factor-beta1 secreted by the proliferating biliary epithelial cells.

Actins↗

PubMed2000

Adenoid basal carcinoma of the uterine cervix: a case report with ultrastructural findings.

Adenoid basal carcinoma of the uterine cervix is a rare tumor with a favorable prognosis. A case of adenoid basal carcinoma (ABC) of the uterine cervix was studied using light and electron microscopy. The patient was a 74-year-old Japanese woman who had undergone hysterectomy due to cervical intraepithelial neoplasia 3. Incidentally, ABC was found in the resected uterus. The tumor cells made small nests and infiltrated the cervical portion of the uterus. In the nests, glands, cribriform patterns with glandlike structures, and squamous differentiation were seen. Immunohistochemically, the glandlike structures were positive for laminin and type IV collagen. Ultrastructurally, the tumor cells had irregular nuclei, scanty cytoplasm, and cribriform patterns in which glandlike structures were covered with basal lamina. No myoepithelial differentiation of the tumor cells was seen. These findings suggest a similarity between adenoid basal carcinomas and adenoid cystic carcinomas. Furthermore, both tumors are considered to originate in the reserve cells of the uterine cervix. Because their outcomes are different, they should be distinguished from each other.

Aged↗

PubMed2000

Mesangial myofibroblastic transformation in steroid-dependent minimal change nephrotic syndrome.

Patients with minimal change nephrotic syndrome (MCNS) occasionally show frequent relapses with proteinuria after cessation of steroid treatment, even though no significant pathological abnormalities are found in the glomeruli, compared with those in nonrelapsed and good-prognosis cases of MCNS. To resolve this contradiction, we immunohistochemically and ultrastructurally examined a biopsied renal tissue of a patient who showed glomerular features of MCNS and frequent clinical relapses. Immunohistochemistry demonstrated the overexpression of alpha-smooth muscle actin (ASMA) and vimentin in glomerular mesangial cells despite no mesangial cell proliferation, compared with nine nonrelapsed cases of MCNS. These facts may be an important clue to the investigation of the pathogenesis of steroid-dependent MCNS with frequent relapses. Furthermore, the immunohistochemical examination of ASMA and vimentin may be useful to detect mesangial myofibroblastic transformation that is not demonstrated in conventional light microscopy and immunofluorescence study.

Actins↗

PubMed2000

Antenatal dexamethasone enhances endothelin receptorB expression in hypoplastic lung in nitrofen-induced diaphragmatic hernia in rats.

BACKGROUND/PURPOSE: The hypoplastic lung and persistent pulmonary hypertension (PPH) are the principle causes of high mortality and morbidity in infants with congenital diaphragmatic hernia (CDH). Endothelin-1 (ET-1), which is produced by vascular endothelial cells and some leukocytes, plays a key role in modulating pulmonary vascular tone in PPH. Two different receptors (ET(A) and ET(B)) for ET-1 have been characterized. Binding of ET-1 to ET(A), which is present on smooth muscle cells in fetal lung, results in vasoconstriction. However, binding of ET-1 to ET(B), which is present on endothelial cells results in vasodilation mediated by endogenous nitric oxide. Antenatal glucocorticoid therapy has been shown to prevent abnormal pulmonary arterial structural changes in animal model with CDH. The aim of this study was to investigate the effect of antenatal glucocorticoid administration on ET-1 system in nitrofen-induced CDH hypoplastic lung in rats. METHODS: A CDH model was induced in pregnant rats after administration of nitrofen on day 9.5 of gestation. Dexamethasone (Dex) was given intraperitoneally on days 18.5 and 19.5 of gestation. Cesarean section was performed on day 21 of gestation. Rat ET-1 protein expression was measured in solubilized lung tissue extracts, by sandwich type enzyme-linked immunosorbent assay (ELISA) analysis. Reverse transcription polymerase chain reaction was performed to evaluate the relative amount of ET-1, ET(A), and ET(B) mRNA expression. RESULTS: The ET-1 protein and mRNA expression of ET-1 and both receptors were increased significantly in CDH lung compared with controls. Although there was no significant difference in ET(A) mRNA expression between CDH lung with Dex treatment and without Dex treatment, ET(B) mRNA expression was elevated significantly in CDH lung with Dex treatment compared with CDH lung without Dex treatment. CONCLUSION: These findings suggest that antenatal glucocorticoid therapy may modulate pulmonary vascular tone in CDH hypoplastic lung by selectively upregulating local expression of ET(B).

Animals↗

PubMed2000

Vinculin: its possible use as a marker of normal collecting ducts and renal neoplasms with collecting duct system phenotype.

Vinculin is a cytoskeletal protein associated with membrane actin-filament-attachment sites of cell-cell and cell-matrix adherens-type junctions. In this article, we examine the expression of vinculin to elucidate its role in human renal neoplasms. We reviewed surgically resected specimens and selected available tissue from 79 renal tumors in 78 patients. There were 55 men and 23 women. Their mean age was 61 years and the mean size of the renal tumors was 6.1 cm. All renal tumors were examined by immunohistochemistry using a monoclonal antibody against vinculin. Overall, 17 (21.5%) renal tumor samples reacted with vinculin. The positive ratio in various types of renal tumors was as follows: conventional-type (clear cell), 0/54; papillary-type, 5/12; chromophobe-type, 5/5; sarcomatoid-type, 3/4; collecting duct carcinoma, 3/3; and oncocytoma, 1/1. The positive rate of conventional-type renal cell carcinomas (RCCs) is significantly different from that of other renal tumors (P < .01). Normal kidney, conventional, and papillary-type RCCs exhibited positive signals in Western blot analysis. These results suggest that vinculin may serve as a useful marker of renal neoplasms with collecting duct system phenotype such as chromophobe-type RCC.

Biomarkers, Tumor↗

PubMed2000

Anaplastic carcinoma of the pancreas with rhabdoid features.

The malignant rhabdoid tumor (MRT) is histologically characterized by the invasive proliferation of polygonal to ovoid cells with abundant eosinophilic cytoplasm and eccentric vesicular nuclei with a prominent nucleolus. MRT frequently occurs in the kidney, but may also arise in other organs. However, MRT should be strictly distinguished from carcinomas with rhabdoid features. A post-mortem examination of a 68-year-old woman found an anaplastic carcinoma of the pancreas with rhabdoid features displaying extensive invasion into the neighboring tissues. To the best of our knowledge, this is the first case of a pancreatic tumor with rhabdoid features. Pathologists should consider that carcinomas showing rhabdoid features may also appear in the pancreas. As pancreatic tumors with rhabdoid features have characteristic histopathological features and poor prognosis compared to other pancreatic tumors, careful histopathological differential diagnosis is important.

Aged↗

PubMed2000

Adult-onset giant juxtaglomerular cell tumor of the kidney.

The juxtaglomerular cell tumor (JGCT) of the kidney is a rare neoplasm which commonly secretes renin. This tumor often occurs in teenagers. This paper documents the 14th adult-onset (over 30-years-old) case with a giant JGCT which measured 9.0 x 8.0 x 7.5 cm. Histologically, this tumor was composed of both vascular and tubular components. Immunohistochemically, the vascular component reacted with renin, cytokeratin 7, ulex europaeus agglutinin-1, vascular endothelial growth factor (VEGF) and Flk-1 (VEGF-R2), whereas the tubular component was positive for renin, epithelial membrane antigen (EMA), cytokeratin 7, alpha-1-antitrypsin, VEGF and Flk-1. This finding suggests that both vascular and tubular components of JGCT may promote neoplastic proliferation via an autocrine mechanism through the action of VEGF.

Female↗

PubMed2000

Bronchial granular cell tumor with osteopontin and osteonectin expression: a case report.

The case of a 52-year-old Japanese man with bronchial granular cell tumors with osteopontin and osteonectin expression is reported here because there have been few investigations of their expression in benign tumors. He was admitted because of sudden hematemesis. A bronchoscopic examination revealed a lobulated polypoid tumor located in the left and right bronchi. Histologically, most tumor cells had abundant granular eosinophilic cytoplasm and were immunoreactive for S-100, neuron-specific enolase (NSE), CD68 and vimentin. Moreover, osteopontin-positive tumor cells were randomly distributed in the tumor tissue, but few stromal cells were positive. In contrast, osteonectin was mainly expressed in the peripheral tumor cells and was also distributed in the stromal cells. Blood vessels at the tumor border in which osteonectin-positive tumor cells were distributed, proliferated moderately. These results suggest that osteopontin and osteonectin may play a role in the progression of granular cell tumors and in the interaction between the tumor and host or angiogenesis around the tumor, respectively.

Biomarkers, Tumor↗

PubMed2000

An immunohistochemical study of developing glomeruli in human fetal kidneys.

BACKGROUND: In the glomerulonephritis, mesenchymal cells frequently repeat the expression of fetal immunohistochemical phenotypes. However, in human glomerulogenesis the phenotypic alteration of mesangial and other types of glomerular cells has not been clearly defined. Our aim was to clarify the characteristics of fetal mesangial cells and glomerular capillary endothelial cells, as well as their changes during glomerulogenesis using immunohistochemistry. METHODS: We examined the renal tissues of 34 autopsied fetuses and neonates, 5 children, and 5 adults using immunohistochemistry and immunoelectron microscopy, using antibodies for cytoskeletons, contraction-associated proteins, and endothelial cell markers. RESULTS: In the V and S stages, there were no cells showing mesangial and endothelial features within the vesicles and the S-shaped bodies. In the S stage, small blood vessels, consisting of endothelial cells (CD31+, CD34+) and primitive perivascular mesenchymal cells (alpha-smooth muscle actin+, low molecular caldesmon+, vimentin+), were branched from developing interlobular arteries and appeared to extend to the lower clefts of the S-shaped bodies. In the C stage, the perivascular mesenchymal cells aggregated at the root of the immature glomeruli. In the M stage, they migrated toward the periphery of immature glomeruli and gradually lost their fetal immunohistochemical features. Similarly, with further maturation, the fetal glomerular capillary endothelial cells gradually lost the immunostaining for CD34, while the strong staining intensity of CD31 remained unchanged, just as that in the adult glomerular capillary endothelial cells. CONCLUSIONS: In human glomerulogenesis, we demonstrate that fetal mesangial and capillary endothelial cells change their immunohistochemical phenotypes with maturation. They gradually lose fetal immunohistochemical phenotypes. Already before birth, the mesangial cells in almost all glomeruli at the late M stage acquire the adult phenotype.

Adolescent↗

PubMed2000

Differential expression of CD34 in normal colorectal tissue, peritumoral inflammatory tissue, and tumour stroma.

AIMS: To investigate the role of CD34 positive stromal cells, namely dendritic interstitial cells, in the desmoplastic stroma formation of malignant epithelial neoplasms the distribution of CD34 positive stromal cells was examined in human colorectal adenocarcinomas, peritumoral inflammatory tissue, and normal tissue. METHODS: Forty one surgically resected human colorectal adenocarcinomas and their corresponding peritumoral inflammatory and normal tissues were examined. To distinguish CD34 positive stromal cells from vascular endothelial cells, immunostaining for both CD34 and CD31 was performed. The distribution of myofibroblasts was also analysed immunohistochemically, and double staining with CD34 and alpha smooth muscle actin (ASMA) was performed. RESULTS: Most of the stromal cells in the normal colorectal submucosa, muscularis propria, subserosa, and perirectal tissue were positive for CD34. In contrast, the peritumoral inflammatory tissue and the tumour stroma had no CD34 positive stromal cells. The distribution of myofibroblasts was almost the same as in the aforementioned series. No stromal cells double positive for CD34 and ASMA were detected in the peritumoral inflammatory tissues. CONCLUSIONS: Most stromal fibroblasts are CD34 positive stromal cells (dendritic interstitial cells). In colorectal adenocarcinomas, a lack of CD34 expression in stromal cells is associated with desmoplastic reaction.

Adenocarcinoma↗

PubMed2000

A case of sarcoidosis presenting as multiple pulmonary nodules, nasopharyngeal and cerebellopontine tumors.

A 64-year-old woman presented with multiple pulmonary nodules, and after spontaneous regression of the pulmonary lesions in six months, nasopharyngeal and right cerebellopontine tumors developed. Noncaseous epithelioid cell granulomas were demonstrated histologically in both resected pulmonary and nasopharyngeal tumors. She complained of hearing loss and tinnitus probably due to the cerebellopontine tumors. Corticosteroid therapy resulted in the improvement of these symptoms and the gradual decrease of tumor size. Although histological probe of the cerebellopontine tumors was not diagnostic, this patient was finally diagnosed as having sarcoidosis, based on the clinicopathological features, including systemic granulomatous lesions, MRI findings, and good response to corticosteroid therapy. The diagnosis of sarcoidosis is sometimes difficult when its clinical manifestations are uncommon.

Cerebellar Diseases↗

PubMed2000

[Misoprostol-induced pneumonitis].

A 76-year-old woman presented with non-productive cough and progressive dyspnea, and was admitted to Oita Medical University Hospital. Arterial blood gas values obtained on admission indicated severe hypoxemia. Chest roentgenograms and computed tomography disclosed diffuse interstitial infiltrates in both lungs. Transbronchial lung biopsy specimens demonstrated thickened alveolar walls with lymphocyte infiltration and swollen type II pneumocyte proliferation. Eosinophils were observed mainly around bronchioles. For approximately 6 months prior to hospitalization, the patient had been given misoprostol, sodium aurothiomalate, prednisolone, and loxoprofen sodium for the treatment of rheumatoid arthritis. Based on the clinical history and findings, drug-induced interstitial pneumonia was suspected. All medications were discontinued, and the patient was then placed on corticosteroids. After treatment, arterial blood gas values improved and the findings on chest roentgenograms cleared up. Positive lymphocyte stimulation tests and positive dermal reaction patch tests implicated misoprostol as an etiologic factor in the patient's interstitial pneumonia. High serum levels of KL-6 and cytokeratin subunit 19 fragment had been detected on admission. These values returned to normal after the interstitial infiltrates had disappeared. To our knowledge, this is the first reported case of misoprostol-induced interstitial pneumonia.

Aged↗

PubMed1999

CD34 expression as a novel marker of transformed mesangial cells in biopsied glomerular diseases.

CD34 is a marker of haematopoietic progenitor cells, stromal precursors, vascular endothelial cells, and a variety of stromal tumour cells. This immunohistochemical study examined the CD34 expression of glomerular mesangial cells in normal and diseased glomeruli and compared it with the staining patterns of alpha-smooth muscle actin (ASMA), as a transformed mesangial cell marker, and CD31, as an endothelial cell marker. In addition, the CD34 and ASMA expression of mesangial cells in various glomerulonephritis and the relationship of the immunostaining intensity to the severity of IgA nephropathy were semiquantitatively evaluated. In normal glomeruli, all cell types were negative for CD34, but in glomeruli in mesangial proliferative glomerulonephritis, CD34 was expressed exclusively in mesangial cells, corresponding to ASMA expression. The dendritic and scattered staining pattern, the mesangial location of positive signals, and the enhanced expression were clearly different from CD31 expression in diseased glomeruli. In comparison with normal controls, the grade of immunostaining for CD34 (CD34 INDEX) in mesangial proliferative glomerular diseases was higher than that of ASMA (ASMA INDEX). With the severity of glomerulonephritis, the CD34 INDEX gradually increased. These studies indicate that CD34 is a useful marker of mesangial transformation and that immunohistochemical examination with the anti-CD34 antibody is useful for the diagnosis and stage determination of glomerular diseases.

Actins↗

PubMed1999

Chondroid chordoma: fine-needle aspiration cytology with histopathological, immunohistochemical, and ultrastructural study of two cases.

Chondroid chordoma is a controversial and confusing entity that was originally described by Heffelfinger et al. (Cancer 1973; 32:410-420) as a biphasic malignant neoplasm possessing elements of both chordoma and cartilaginous tissue. Fine-needle aspiration (FNA) cytology of chondroid chordoma has not been described. The aim of our investigation was to characterize the chondroid area of chondroid chordoma and to compare the FNA features with those of well-differentiated chondrosarcoma. Clival and cervical spine chondroid chordomas were studied with light microscopy, immunohistochemistry, and electron microscopy. Chondroid chordomas demonstrated an epithelial nature by immunohistochemistry and ultrastructural studies. The FNA smears showed low cellularity, with loosely arranged or dispersed round cells in a myxoid background. Although the smears were similar to those of well-differentiated chondrosarcomas, they showed a positive reaction for epithelial markers. These findings reveal that chondroid chordoma is a variant of chordoma which possesses a hyaline matrix. Immunohistochemical demonstration of epithelial markers is useful to distinguish it from chondrosarcoma. Diagn. Cytopathol. 1999; 21:335-339.

Biomarkers, Tumor↗

PubMed1999

Effect of antenatal glucocorticoid administration on insulin-like growth factor I and II levels in hypoplastic lung in nitrofen-induced congenital diaphragmatic hernia in rats.

There is increasing evidence to suggest that insulin-like growth factors (IGF) I and II play a crucial role in fetal lung development. Expression of IGF-I and II has been demonstrated to be predominant during fetal life and decreases prior to birth. Antenatal glucocorticoids are reported to improve lung immaturity. The aim of this study was to investigate the effect of antenatal glucocorticoid administration on IGF-I and II expression in nitrofen-induced congenital diaphragmatic hernia (CDH) in rats. A CDH model was induced in pregnant rats following administration of 100 mg nitrofen on day 9.5 of gestation (term = 22 days). Dexamethasone (0.25 mg/kg) was given intraperitoneally on days 18.5 and 19.5 of gestation. Cesarean section was performed on day 21. The fetuses were divided into three groups: I, normal controls; II, nitrofen-induced CDH; and III, nitrogen-induced CDH with antenatal dexamethasone treatment. mRNA was extracted from whole lung and a reverse transcription-polymerase chain reaction (RT-PCR) was performed to evaluate the relative amounts of IGF I and II mRNA. Levels of mRNA were expressed as a ratio of the band density divided by that of beta-actin, a housekeeping gene known to be expressed at a constant level. Immunohistochemistry using anti-rat IGF I and II antibody was also performed in each group. Levels of IGF I mRNA were significantly increased in group II (0.50 +/- 0.08) compared to group I (0.34 +/- 0.10) or group III (0.32 +/- 0.06) (P < 0.05). Levels of IGF II mRNA were also significantly increased in group II (0.95 +/- 0.20) compared to group I (0.42 +/- 0.07) or group III (0. 31 +/- 0.09) (P < 0.05). Strong IGF I and II expression was observed in the hypoplastic CDH lung (group II), mainly in the bronchiolar epithelium. IGF I and II expression in group I and III lungs was either absent or weak. The finding of significant reductions in IGF I and II mRNA and protein levels in dexamethasone-treated CDH lung suggest that dexamethasone may accelerate the fetal stage of lung development.

Animals↗

PubMed1999

Increased tropoelastin and procollagen expression in the lung of nitrofen-induced diaphragmatic hernia in rats.

BACKGROUND/PURPOSE: Collagen and elastin, the predominant components of the lung connective tissue network, have been suggested to have an important influence on lung compliance and maximal expansion. Decrease in lung compliance and distensibility often is seen in human congenital diaphragmatic hernia (CDH) lung as well as in experimentally produced CDH lung. The aim of this study was to investigate mRNA levels of tropoelastin and alpha1 (I) procollagen, the precursors of elastin, and type I collagen, respectively, in CDH lung and to determine whether antenatal dexamethasone treatment has any effect on the production of these extracellular matrix proteins. METHODS: CDH model was induced in pregnant rats after administration of 100 mg nitrofen on day 9.5 of gestation (term, 22 days). Dexamethasone (0.25 mg/kg) was given on day 18.5 and 19.5. Cesarean section was performed on day 21. The fetuses were divided into three groups: group I, normal controls; group II, nitrofen-induced CDH; and group III, nitrofen-induced CDH with antenatal dexamethasone treatment. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to evaluate relative amounts of tropoelastin and alpha1 (I) procollagen mRNA. RESULTS: Levels of both tropoelastin and alpha1 (I) procollagen mRNA were significantly increased in group II compared with group I (P< .05). Neither tropoelastin nor alpha1 (I) procollagen mRNA levels were significantly different between group II and III. CONCLUSIONS: The increased local synthesis of tropoelastin and type I procollagen in CDH lung may be responsible for the increased rigidity and decreased compliance observed in the CDH hypoplastic lung. Glucocorticoids have no effect on pulmonary tropoelastin and alpha1 (I) procollagen gene expression in CDH lungs.

Animals↗