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H Kitamura

Publications and source records attributed to H Kitamura.

At least 235 records · Page 13Linked to original sources
PubMed1997

Pure ovarian ependymoma: report of a case treated with surgery, chemotherapy, irradiation and hyperthermotherapy.

Ependymomas usually develop from neuroectodermal organs. Pure ovarian ependymoma is an extremely rare tumor. We report a patient with ovarian ependymoma who died at the age of 28, 9 years after initial surgery and subsequent intensive combination therapy (chemotherapy, irradiation and hyperthermotherapy) for repeated relapses and metastatic tumors. The diagnosis was confirmed by histopathological and immunohistochemical studies. For recurrent and persistent ependymoma, a combination of the treatment modalities described above is suggested to be beneficial in attenuating the rapid progress and spread of this disease.

Adolescent↗
PubMed1997

Detection and clinical significance of red cell aggregation in the human subcutaneous vein using a high-frequency transducer (10 MHZ): a preliminary report.

To assess ultrasonic measurements for quantitative analysis of red cell aggregation in humans, 50 patients admitted to our hospital were examined without selection. The extent of the aggregates was a assessed by videodensitometry in the subcutaneous vein in the forearm after 2 min of occlusion by manual compression over the skin. Determinants of aggregability were also evaluated by laboratory blood testing to identify potential correlations with ultrasound data. Multiple regression analysis showed that echogenicity was significantly associated with plasma fibrinogen (p < 0.0001), serum total cholesterol (p = 0.0006) and serum protein fraction excluding albumin (p = 0.0049) and was inversely associated with serum total triglyceride (p = 0.0425), but not with age or hematocrit. Ultrasound measurements of red cell aggregation seemed to be useful for the assessment not only for a part of the rheological condition of the blood, but also concomitant changes in plasma macromolecules.

Cholesterol↗
PubMed1997

Pulmonary endocrine cell hyperplasia and papilloma in rats induced by intratracheal injections of extract from particulate air pollutants.

We investigated the effect of intratracheal injections of an extract of suspended particulate matter (SPM) obtained from the urban ambient air of Tokyo, upon the development of proliferative lesions of pulmonary endocrine cells (PECs) in the rat. We also examined the modification effects of nitrogen dioxide, sulfur dioxide, or both of them on the PEC lesions. Male F344 rats were divided into six experimental groups of 5 animals each. Twenty animals were treated with intratracheal instillations of SPM admixed with carbon once a week for 4 weeks with or without additional gaseous exposure (6 ppm nitrogen dioxide or 4 ppm sulfur dioxide) 16 hrs a day for 11 months. Five animals were given intratracheal injections of carbon suspended in saline and the other five were untreated. The subcardiac lobes of the right lung were fixed with 4% paraformaldehyde, and embedded in paraffin. PEC hyperplasias and papillomas were counted in 200 serial sections, 4 microns thick. The average incidences of PEC hyperplasia in the untreated animals and in those treated with carbon were 194 and 200/cm3, respectively. The average incidences of PEC hyperplasia in the animals exposed to SPM tar only, SPM tar plus nitrogen dioxide and sulfur dioxide, SPM tar with nitrogen dioxide and SPM tar with sulfur dioxide were 376, 378, 372 and 349/cm3, respectively. These were significantly higher than the levels of the control animals, and additional gaseous stimuli had no effect on the incidence of PEC hyperplasia. Besides PEC hyperplasia, a few PEC papillomas were found in the animals treated with SPM tar, regardless of gaseous exposure, but in the control animals no papilloma was evident. Thus, compounds in airborne particulates are considered to be responsible for the development of PEC hyperplasias and papillomas.

APUD Cells↗
PubMed1997

Plasma concentration of endothelin-1 does not reflect renal vasoconstriction as estimated by duplex ultrasonography in cirrhosis.

Endothelin, a potent vasoconstrictor, is thought to play a role in liver cirrhosis-related functional kidney failure. Our aim was to investigate the correlation between renal vasoconstriction, as detected by a Doppler ultrasound technique, and plasma concentrations of endothelin in cirrhotic patients. Fifty cirrhotic patients underwent Doppler examinations to detect renal vasoconstriction. The plasma concentration of endothelin was measured in 10 patients who exhibited vasoconstriction of the renal microvessels diagnosed by Doppler waveform analysis and was compared to that of patients in whom there was no sign of such vasoconstriction. No difference was observed in the plasma concentration of endothelin between patients in whom renal vasoconstriction was diagnosed and those in whom it was not. Our results suggested that the circulating endothelin does not reflect renal vasoconstriction, at least in the early phase of the functional renal failure associated with cirrhosis of the liver.

Endothelin-1↗
PubMed1997

Complexity of expression of the intermediate filaments of six new human ovarian carcinoma cell lines: new expression of cytokeratin 20.

Six permanent human ovarian carcinoma cell lines (OVISE, OVTOKO, OVMANA and OVSAYO from clear cell adenocarcinoma, and OVSAHO and OVKATE from serous papillary adenocarcinoma) were established from solid tumours. The cell lines have been in culture for 5-8 years, the passage number varying from 62 to 246. Immunohistochemical analysis has shown that five of the six cell lines express at least six cytokeratin (CK) polypeptides. OVISE and OVSAYO expressed CKs 6, 7, 8, 18, 19 and 15 and/or 16. OVTOKO was positive for CKs 7, 8, 18, 19 and 15 and/or 16. OVSAHO expressed CKs 6, 7, 8, 14, 18, 19 and 15 and/or 16. OVMANA expressed CKs 6, 7, 8, 18, 19, 20 and 15 and/or 16. OVKATE expressed CKs 6, 7, 8, 13, 17, 18, 19, 20 and 15 and/or 16. The expression of CK7, additional expression of vimentin, and clinical and histopathological findings enabled us to confirm that six cell lines had been established from primary ovarian cancers. Two of the six cell lines were positive for CK20, although CK20 was not expressed in the original tumours. The heterotransplanted tumours produced by CK20-positive cells also expressed CK20. This is the first report of ovarian carcinoma cell lines that express CK20 irrespective of their histological type. CK20 has been found in all colon carcinoma cell lines, but only in the mucinous type of ovarian tumours. These new ovarian carcinoma cell lines will therefore provide a relevant experimental system for elucidating the regulatory control mechanisms of intermediate filament expression.

Adenocarcinoma, Clear Cell↗
PubMed1997

Effects of partial nephrectomy on the expression of osmolyte transporters.

Na+/myo-inositol cotransporter (SMIT) and Na+/Cl-/betaine-gamma-amino-n-butyric acid transporter (BGT-1) are the major osmolyte transporters that are regulated by extracellular osmolarity. We have recently shown localization and rapid regulation of the mRNAs for these transporters in rat kidney. In the present study, we examined the expression of SMIT and BGT-1 in partial nephrectomized rats in order to assess the change in local osmolarity following reduction of renal mass. Four weeks after 5/6 nephrectomy (NX), the rats were compared to sham-operated control animals (CONT). Northern analysis using RNA of whole kidney indicated that there were little differences in the levels of SMIT and BGT-1 mRNAs between the two groups. In situ hybridization revealed that signals for both transporter mRNAs were markedly reduced in the inner medulla of the remnant kidney. In contrast, these signals in the outer medulla increased following nephrectomy. SMIT signals in the cortex increased as well. Grain density, determined by counting grain number per cell, revealed that the signals in the inner medullary collecting ducts were markedly reduced whereas those in the thick ascending limbs of Henle (TAL) as well as macula densa cells were significantly increased. The signals in the TAL and macula densa were reduced by furosemide administration. The increased expression in NX rats may reflect the increased NaCl transport and high local osmolarity in this segment.

Animals↗
PubMed1997

Ultrastructural study of capillary and myocytic changes in the masseter and heart of KK-Ay mice.

We studied the capillaries and myocytes of masseter and cardiac muscles of diabetic KK-Ay mice, using light microscopy, transmission electron microscopy and scanning electron microscopy. The following changes were observed for diabetic masseters: capillary tortuosity, diversity of capillary caliber, endothelial cell swelling accompanied by luminal narrowing, widening of the pericapillary space and pericapillary fibrosis, and subsarcolemmal accumulation of myocytic mitochondria in areas adjacent to capillaries. In addition, attenuated capillary segments were largely covered by pericytes with profuse processes. In contrast, cardiac muscles of KK-Ay mice exhibited subsarcolemmal accumulation of myocytic mitochondria in areas contiguous to capillaries, and degenerative changes of myocytes such as disarrangement of myofilaments, disappearance of Z-bands and clustering of lipid-like vacuoles, although conspicuous changes of capillaries were not noted. Microvascular and myocytic changes described above may suggest the presence of microangiopathy and myopathy in the masseter and heart of KK-Ay mice.

Animals↗
PubMed1997

Effects of inhibition of myo-inositol transport on MDCK cells under hypertonic environment.

To investigate the role of myo-inositol under hypertonic conditions, we examined the effects of inhibition of myo-inositol transport in Madin-Darby canine kidney (MDCK) cells using an analog of myo-inositol, 2-O,C-methylene-myo-inositol (MMI). We first characterized the inhibitory effects of MMI on myo-inositol transport in MDCK cells. The Na+-dependent component of [3H] myo-inositol uptake was inhibited by MMI in a concentration-dependent manner, although MMI did not inhibit the activities of the betaine transporter and system A neutral amino acid transporter. We found decreased affinity for myo-inositol in the presence of MMI, whereas the maximal velocity (Vmax) of the transporter did not change. Thus MMI behaves as a competitive inhibitor of myo-inositol transport with a relatively high inhibition constant (K(i)) value (1.6 mM). Myo-inositol content in hypertonic MDCK cells was markedly reduced in the presence of 5 mM MMI, but MMI itself did not accumulate in these cells. The hypertonic cells began to detach in the presence of MMI 3 days after increasing medium osmolality, whereas MMI did not affect the cells in isotonic medium. We also examined the effects of MMI on colony-forming efficiency of MDCK cells. MMI decreased colony-forming efficiency in a concentration-dependent manner, and addition of myo-inositol returned the efficiency to the value without MMI. Addition of betaine also increased colony-forming efficiency in the presence of MMI. These results indicate that myo-inositol plays an important role in survival and growth under hypertonic environment.

Animals↗
PubMed1997

Organization of the lamina propria mucosae of rat intestinal mucosa, with special reference to the subepithelial connective tissue.

Light microscopy, scanning electron microscopy and transmission electron microscopy have been used to delineate the structure and function of the lamina propria mucosae in the rat jejunum. In silver-impregnated sections, the adepithelial surface of the lamina propria mucosae was framed by a sheet of reticular fibers (reticular sheet). Short-term (3-hour) immersion of jejunal tissues in 2 N NaOH solution enabled us to simultaneously view networks of reticular fibrils and fibroblasts residing in the subepithelial connective tissue under a scanning electron microscope. The reticular fibrils, which measured about 40 nm in diameter and were interwoven in dense networks, formed a sheet 2-3 microns thick. In the villi, this sheet contained numerous foramina ranging from 3 to 7 microns in diameter, through which lymphocytes, macrophages, basal extensions of epithelial cells and fat particles traversed. The reticular sheet in the domes of isolated lymphoid nodules was markedly porous, and many lymphocytes migrated into or out of the epithelium through the foramina. The formaina of the reticular sheet may participate in the communication between the intestinal epithelium and the lamina propria mucosae. It was noted that the foramina of the reticular sheet in the villi were surrounded by end feet of the cytoplasmic processes of fibroblasts. In addition, these fibroblasts were combined with lymphocytes or dendritic cells in the lamina propria mucosae.

Animals↗
PubMed1997

Pre-operatively determined prognostic factors in metastatic renal cell carcinoma.

OBJECTIVES: The aim of this study was to clarify the pre-operatively determined factors affecting the prognosis in patients with metastatic renal cell carcinoma (RCC). METHODS: We analyzed 69 patients with metastatic RCC who received nephrectomy. Multivariate analysis by Cox's proportional hazards model and survival studies were applied. RESULTS: Tumor thrombus in a renal vein or vena cava was the most significant poor-prognostic factor, followed by multiple-organ metastases and three or more abnormal findings of factors related to acute-phase proteins, in this order. Seven patients having these three risk factors died of cancer within 7 months after nephrectomy. On the other hand, half of the patients without risk factors survived for more than 2 years. CONCLUSIONS: Risk status should be used for selection of metastatic-RCC patients for treatment of the primary site.

Acute-Phase Proteins↗
PubMed1997

Demonstration and organization of duct-associated lymphoid tissue (DALT) of the main excretory duct in the monkey parotid gland.

Duct-associated lymphoid tissue (DALT) of the main excretory duct in the monkey parotid gland was first demonstrated by light microscopy and by transmission and scanning electron microscopy. The DALT included a follicular area, a parafollicular area and a specialized overlying epithelium with distinct fine-structural elements. There was usually a solitary lymphoid follicle located in the subepithelial area near the orifice of the parotid duct. The lymphoid follicles typically had a distinct germinal center. Numerous immune cells often infiltrated into the epithelium overlying the lymphoid follicle. The superficial epithelial cells of the DALT were larger and flatter than the ordinary duct epithelial cells, and had short irregular microvilli on their luminal surface. They were also in close contact with immune cells such as dendritic cells and lymphocytes. Goblet cells were rare in this area. In addition, bacteria, seen at the duct orifice, were sometimes taken up by the flattened epithelial cells near the orifice. Latex microspheres administrated as particulate antigens at the duct orifice were selectively taken up by the flattened epithelial cells and also by the intraepithelial dendritic cells of the DALT. These morphological findings suggest that the epithelial cells of the DALT in parotid glands take up antigens from the duct lumen and transport them to adjacent immune cells, and that the DALT in parotid glands may serve as one of the inductive sites in the common mucosal immune system.

Animals↗
PubMed1997

Malignant solitary fibrous tumor arising in the right buttock associated with metastatic parietal pleural and intrapulmonary tumors in addition to pleural effusion.

A malignant solitary fibrous tumor arising in the right buttock associated with metastatic parietal pleural and intrapulmonary tumors and pleural effusion was found in a 59-year-old man. A chest computed tomogram revealed three tumors attached to the parietal pleura with rib destruction, and a tumor in the left lower lung field. Histologically, the tumors of the buttock and parietal pleura were characterized by proliferation of bundles of spindle-shaped or oval cells separated by wavy hyalinized collagen tissue with no expression of cytokeratin, S-100 protein, muscle actin or epithelial membrane antigen, but these cells weakly expressed CD34 and strongly expressed vimentin.

Biomarkers, Tumor↗
PubMed1997

[Endoscopic reconstruction after traumatic disruption of the urethra].

Endoscopic reconstruction was performed in 5 patients after complete traumatic disruption of the urethra. A prostatic urethra was disrupted in 1 patient, prostatic and membranous urethrae in 1 and bulbous urethra in 3. After endoscopic reconstruction, all patients required additional internal urethrotomy and urethral bougienage, but became able to void by themselves. Four patients had maximum flow rates between 13.8 and 41.9 ml/s. However, the other patient with an obliterated urethral segment of 4.6 cm had traumatic impotence preoperatively and a poor voiding status after reconstruction. None of the patients developed urinary incontinence or impotence associated with the operation. In conclusion, endoscopic reconstruction is recommended as the initial procedure for patients with obliterated segments smaller than 3 cm.

Accidents, Occupational↗
PubMed1997

Genetic analysis in Japanese kindreds of congenital type I antithrombin deficiency causing thrombosis.

We have identified two novel minor deletions (case 1; -TA or -AT at nucleotide 9831-3 in exon 5 and case 2; -A at nucleotide 7640-1 in exon 4), one novel nonsense mutation (case 3; TAT to TAA at nucleotide 7491 in exon 4), and one recurrent nonsense mutation (case 4; CGA to TGA at nucleotide 5381 in exon 3A) in Japanese kindreds with congenital type I antithrombin deficiency. The deletion detected in case 1 represented a symmetric element (CTCTGTCTC) and possessed a direct repeat (CTCTATGTCTC). The deletion in case 2 was recognized in a consensus sequence (TGAAT) and possessed a direct repeat (GATGAA). The nonsense mutation in case 3 formed a palindrome (CCGTTAACGG) and that in case 4 was caused by a CpG dinucleotide mutation. These results confirm that the mutations of congenital type I antithrombin deficiency are not random events but are influenced strongly by DNA sequences.

Adult↗
PubMed1997

[Peripheral carcinoid tumor of the lung presenting as a solitary mass shadow on a chest roentgenogram and diagnosed by CT-guided percutaneous needle biopsy].

A 59-year-old woman was referred to our clinic because a solitary mass shadow (2.5 cm in diameter was seen in the left lower lung field on a chest roentgenogram. Transbronchial biopsy via a fiberoptic bronchoscope did not yield a definitive diagnosis. Examination of a specimen obtained by CT-guided percutaneous needle biopsy revealed that the tumor consisted of small cells proliferating in a solid, tubular, pseudoglandular, and follicular pattern, which suggested the diagnosis of carcinoid. A left lower lobectomy was performed, and several hilar and mediastinal lymph nodes were also removed. The tumor cells did not show pleomorphism of nuclei, mitotic activity, or necrosis. Grimelius and immunohistochemical stains for chromogranin. A, neuron-specific-enorase, synaptophysin, and serotonin were positive. These findings confirmed the diagnosis of carcinoid CT-guided percutaneous needle biopsy can be useful for the diagnosis of peripheral carcinoid and other peripheral lung tumors.

Biopsy, Needle↗
PubMed1997

Angiotensin II increases plasminogen activator inhibitor-1 and tissue factor mRNA expression without changing that of tissue type plasminogen activator or tissue factor pathway inhibitor in cultured rat aortic endothelial cells.

Angiotensin converting enzyme inhibitors (ACE-I) have been reported to prevent the recurrence of cardiovascular events. The mechanism of this decrease, however, can not be completely explained by anti-hypertensive and anti-hypertrophic effects of ACE-I. To investigate the mechanism of this decrease, we studied the regulation of plasminogen activator inhibitor-1 (PAI-1), tissue type plasminogen activator (TPA), tissue factor (TF), and tissue factor pathway inhibitor (TFPI) by angiotensin II (Ang II) in cultured rat aortic endothelial cells. Ang II increased PAI-1 and TF mRNA expression without affecting that of TPA or TFPI. These inductions were accompanied by increases in PAI-1 and TF activities and were inhibited by a type I Ang II receptor antagonist. The results suggest that Ang II decreases the antithrombotic properties of endothelial cells which increases the chance of thrombosis. Thus, inhibition of the renin-angiotensin system may be beneficial to prevent thrombus formation in treatment of ischemic heart disease.

Angiotensin II↗
PubMed1997

Analysis of p21Waf1/Cip1 expression in normal, premalignant, and malignant cells during the development of human lung adenocarcinoma.

Our studies suggested that adenocarcinoma of the peripheral lung mostly develops by several steps from atypical adenomatous hyperplasia through early adenocarcinoma to overt adenocarcinoma, and that some p53 abnormalities play an important role in this progression. In the present study, we examined by immunohistochemistry the expression of p53-inducible cyclin-dependent kinase inhibitor p21Waf1/Cip1 (p21) in the cells at various developmental stages of lung adenocarcinoma (32 lesions of adenomatous hyperplasia, 14 of early adenocarcinoma, 23 of well differentiated adenocarcinoma, and 17 of moderately or poorly differentiated adenocarcinoma) in comparison with 19 reactive proliferative lesions and analyzed the relationship between p53 and p21 expression. Bronchioalveolar cells in the normal lung expressed very little or no p21 and no p53 expression. In not only reactive but also neoplastic lesions regardless of their developmental stage, the cells expressed p21 at various frequencies. The average labeling indices ranged from 5.4 to 13.8%, and there was no significant difference between any of these categories. The expression of p21, however, tended to be relatively low in moderately and poorly differentiated adenocarcinomas (5.5%) compared to well differentiated adenocarcinomas (12.2%), and high-level p21 expressors (10% < or = positive cells) were more frequent in the latter group (1 of 17 (6%) versus 3 of 23 (35%), P < 0.05), suggesting that p21 expression is affected by the degree of differentiation of the neoplastic cells. Although the correlation was positive between the expression of p21 and p53 in reactive lesions (r = 0.88; P < 0.001), none was found in neoplastic lesions at any step or grade (-0.12 < or = r < or = 0.26). These results indicated that p21 expression depends upon p53 expression in reactive lung cells, whereas p21 expression is at least in part independent of that of p53 from the earliest to the most fully developed step of lung adenocarcinoma tumorigenesis. We concluded that disruption of the p53-dependent cell cycle regulation is a very early event in the tumorigenesis of lung adenocarcinoma.

Adenocarcinoma↗