Biomedical subjects

Y Nakano

Publications and source records attributed to Y Nakano.

At least 199 records · Page 11Linked to original sources

PubMed1999

The significance of the difference in bacterial adherence between bladder and ileum using rat ileal augmented bladder.

OBJECTIVES: Intestinal segments are frequently used in the reconstruction of the urinary tract. Chronic bacteriuria is frequently observed in these patients, but the reason is not clearly understood. Therefore, we studied the difference in bacterial adherence between bladder and ileum using the rat ileal augmented bladder model to investigate the cause of chronic bacteriuria. MATERIALS AND METHODS: Augmentation of the bladder using ileum and a sham operation were performed under sodium pentobarbital in 102 and 10 Sprague-Dawley rats, respectively. At three months after the operation, urinary pH and plasma concentration of sodium, chloride and potassium were measured and urinary culture was done. Urovirulence factors of Escherichia coli aspirated from augmented bladder were detected by polymerase chain reaction (PCR). Five to six rats with negative urinary cultures after the augmentation were used for each experimental cystitis. E. coli with type I pili aspirated from augmented rats and three clinically isolated strains of E. coli, C5 (type I pili, aerobactin), C92 (type I pili, aerobactin, P fimbriae), and C189 (type I pili, aerobactin, P fimbriae, CNF), were transurethrally inoculated into the augmented bladder of rats. Fourteen days after inoculation, rats were sacrificed and colony-forming units (CFU) per mg. of tissue of bladder and ileum were measured. RESULTS: After operation, urinary pH and the serum level of chloride in all augmented groups were higher than those of the controls. Bacterial colonization was observed in 56 of 89 rats. Most of them were E. coli having only type I pili as a virulence factor. In contrast, the sham operated group revealed no bacterial colonization. In experimental cystitis, E. coli with only type I pili aspirated from augmented rats and E. coli C5 were clearly adhered to ileum rather than to bladder, but E. coli C92 and C189 showed no significant difference with respect to adherence to the two tissues. In experimental cystitis II, E. coli C5 with D-mannose were washed out in 3 of 5 rats by 14 days, while E. coli C5 without D-mannose were not washed out in all rats by 14 days. CONCLUSIONS: These results suggested that the difference in bacterial adherence due to urovirulence factors, especially type I pili, is one of the main causes of asymptomatic bacteriuria after urinary reconstruction.

Animals↗

PubMed1999

Expression of tumor necrosis factor-alpha and interleukin-6 in oral squamous cell carcinoma.

To explore the role of cytokines in tumor development and clinical manifestations, we examined the expressions of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in tumor tissues obtained from 57 patients with oral squamous cell carcinoma (OSCC) and their relationships to pathological grade and staging. Enzyme-linked immunosorbent assay on the tumor tissues demonstrated elevated concentrations of TNF-alpha and IL-6 proteins and upregulated mRNA levels were detected by the reverse transcription-polymerase chain reaction method when compared to those in normal control tissues. These cytokines and their transcripts were localized in stromal macrophages and in the tumor cells in particular of the front area of tumor tissues, possibly indicating active synthesis of these cytokines by tumor cells. Larger-sized tumors (T3, 4) contained significantly greater levels of IL-6 proteins than small-sized tumors (T1, 2) (P<0.05). The levels of these cytokines were significantly reduced in cases with effective pre-treatment with radiation or anti-cancer agents compared to those in the less effective group (P<0.05, grade IIa vs. grade IV for both TNF-alpha and IL-6). The present study thus demonstrated enhanced expression of cytokines in OSCC tissues.

Carcinoma, Squamous Cell↗

PubMed1999

Recombination between gtfB and gtfC is required for survival of a dTDP-rhamnose synthesis-deficient mutant of Streptococcus mutans in the presence of sucrose.

The rml genes are involved in dTDP-rhamnose synthesis in Streptococcus mutans. A gene fusion between gtfB and gtfC, which both encode extracellular water-insoluble glucan-synthesizing enzymes, accompanied by inactivation of the rml genes was observed for cells grown in the presence of sucrose. The survival rates of rml mutants isolated in the absence of sucrose were drastically reduced in the presence of sucrose. The rates were consistent with the frequency of spontaneous gene fusions between gtfB and gtfC, suggesting that the spontaneous recombinant organisms were selected in the presence of sucrose. The rml mutants with a gtfB-gtfC fusion gene had markedly reduced water-insoluble glucan synthetic activity and lost the ability to colonize glass surfaces in the presence of sucrose. These results suggest that the rml mutants of S. mutans, which are defective in dTDP-rhamnose synthesis, can survive only in the absence of water-insoluble glucan synthesis.

Gene Expression Regulation, Bacterial↗

PubMed1999

A novel gene required for rhamnose-glucose polysaccharide synthesis in Streptococcus mutans.

Gene rgpG is required for biosynthesis of rhamnose-glucose polysaccharide (RGP) in Streptococcus mutans. Its deduced amino acid sequence had similarity to WecA, which initiates syntheses of enterobacterial common antigen and some O antigens in Escherichia coli. Gene rgpG complemented a wecA mutation of E. coli, suggesting that rgpG may function similarly in RGP synthesis.

Cloning, Molecular↗

PubMed1999

Comparison of low attenuation areas on computed tomographic scans between inner and outer segments of the lung in patients with chronic obstructive pulmonary disease: incidence and contribution to lung function.

BACKGROUND: The low attenuation areas on computed tomographic (CT) scans have been reported to represent emphysematous changes of the lung. However, the regional distribution of emphysema between the inner and outer segments of the lung has not been adequately studied. In this study the regional distribution of low attenuation areas has been compared by quantitative CT analysis and the contribution of the regional distribution to pulmonary function tests evaluated in patients with chronic obstructive pulmonary disease (COPD). METHODS: Chest CT images and the results of pulmonary function tests were obtained from 73 patients with COPD. The lung images were divided into inner and outer segments in the upper (cranial), middle, and lower (caudal) sections. The percentage ratio of low attenuation area to corresponding lung area (LAA%) was then calculated. The LAA% of each segment was also compared with the results of pulmonary function tests. RESULTS: The mean (SD) LAA% of the inner segment was 39.1 (18.5) compared with 28.1 (13.2) for the outer segment (p<0.0001). Linear and multiple regression analyses revealed that airflow limitation is closely correlated with the inner segment LAA% of the lower lung. In contrast, the carbon monoxide transfer factor is closely correlated with the inner segment LAA% of the upper lung. CONCLUSION: Low attenuation areas on CT scans are more often found in the inner segment of the lung than in the outer segment, and the contribution of the inner segment to pulmonary function tests may be greater than the outer segment.

Aged↗

PubMed1999

Acute response of the lung mechanics of the rabbit to hypoxia.

We measured the change in total lung resistance (RL) and that in total lung elastance (EL) induced by hypoxia (n = 7) and compared the results with those by intravenous histamine bolus (n = 5) at three different positive end-expiratory pressure (PEEP) levels (2, 5, and 8 hPa) in open-chest and vagotomized rabbits. The percent increase ratio of RL (PIRR) and EL (PIRE) was defined as the change in RL and EL, respectively, induced by hypoxia compared with that in the normoxic condition, expressed as a percentage. PIR values for the change in RL and EL induced by bolus injection of histamine were also calculated. The PIRR and PIRE induced by hypoxia and by histamine were positive by a statistically significant amount at every PEEP level, except for the PIRE value at 8-hPa PEEP in the hypoxic challenge. The PIRE-to-PIRR ratio values in the hypoxic challenge at 2-hPa PEEP were significantly larger than those in the histamine challenge (hypoxia: 0.91 +/- 0.23%; histamine: 0.37 +/- 0. 065%, P < 0.05). The increase in EL induced by histamine in the acute phase has been reported to be mainly derived from tissue distortion secondary to bronchial constriction. Thus our results suggest that a part of the increase in EL by hypoxia was originated in different parenchymal responses from histamine and imply that this hypoxic response of lung parenchyma is sensitive to the increase in parenchymal tethering at high PEEP levels.

Airway Resistance↗

PubMed1999

Antigen-specific, IgE-selective unresponsiveness induced by antigen-liposome conjugates. Comparison of four different conjugation methods for the coupling of antigen to liposome.

BACKGROUND: We have previously reported that ovalbumin (OVA) coupled with liposome via glutaraldehyde (GA) induced OVA-specific- and IgE-selective unresponsiveness in mice. METHODS: In this study, OVA-liposome conjugates were made using four different coupling protocols: via GA, N-(6-maleimidocaproyloxy) succinimide (EMCS), disuccinimidyl suberate (DSS) and N-succimidyl-3(2-pyridyldithio)propionate (SPDP) and the induction of antigen-specific IgG and IgE antibody production was investigated for each. In addition, antigen-specific cytokine production by spleen cells of mice immunized either with OVA-liposome or with OVA adsorbed with aluminum hydroxide was investigated. RESULTS: OVA-liposome conjugates coupled via GA or DSS did not induce anti-OVA IgE antibody production but induced substantial anti-OVA IgG antibody production. On the other hand, the induction of anti-OVA IgE unresponsiveness by OVA-liposome conjugates coupled via EMCS or SPDP was incomplete. The amount of interleukin 4 (IL-4) produced by spleen cells stimulated in vitro with OVA correlated well with anti-OVA IgE antibody production in donor mice. However, the production of no other cytokine, i.e., IL-2, IL-5, IL-10 or interferon-gamma, was correlated with in vivo IgE antibody production. CONCLUSION: OVA-liposome coupled via GA or DSS induced complete suppression of anti-OVA IgE production. The results in this study further suggest that the regulation of IgE antibody production does not necessarily correlate with so-called Th1 cytokine production.

Animals↗

PubMed1999

Course of IL-1beta, IL-6, IL-8, and TNF-alpha in the middle ear fluid of the guinea pig otitis media model induced by nonviable Haemophilus influenzae.

To characterize the local response in acute otitis media, courses of interleukin (IL)-1beta, IL-6, IL-8, and tumor necrosis factor (TNF)alpha in middle ear fluid (MEF) of the guinea pig otitis media model induced by nonviable Haemophilus influenzae were investigated with enzyme-linked immunosorbent assay (ELISA) kits. The IL-1beta concentration in H. influenzae-inoculated ears peaked 24 hours after inoculation. The IL-8 concentration was significantly higher in H. influenzae-inoculated ears than in controls 48 and 96 hours after inoculation. The TNF-alpha concentration in H. influenzae-inoculated ears had an initial peak 6 hours after inoculation and had significant late increases 48 and 96 hours after inoculation. The results suggest that IL-1beta and TNF-alpha were produced by middle ear mucosa in the early stage of the experiment by stimulation of bacterial inoculation, which caused subsequent inflammatory cell accumulation, and that IL-8 and TNF-alpha were produced in the late stage by accumulating inflammatory cells.

Acute Disease↗

PubMed1999

Regulation of gelatin-binding protein 28 (GBP28) gene expression by C/EBP.

We have previously reported the isolation of human gelatin-binding protein 28 (GBP28) gene which is specifically expressed in adipose tissue. The transcriptional activity of the flanking region of the GBP28 gene was examined by the transient transfection of promoter-luciferase reporter constructs into 3T3 adipocytes and electrophoretic mobility shift assay. This revealed the existence of a protein which binds to the 5'-flanking region of the GBP28 gene in nuclear extracts from human adipose tissue, but not in nuclear extracts from mouse liver. The C/EBP sites contained in this region are thought to take part in the regulation of GBP28 gene expression.

3T3 Cells↗

PubMed1999

Antiproliferative constituents from umbelliferae plants. V. A new furanocoumarin and falcarindiol furanocoumarin ethers from the root of Angelica japonica.

The CHCl3 extract of the root of Angelica japonica showed high inhibitory activity against human gastric adenocarcinoma (MK-1) cell growth. From this extract, a new furanocoumarin named japoangelone and four furanocoumarin ethers of falcarindiol, named japoangelols A-D, were isolated together with caffeic acid methyl ester, four polyacetylenic compounds (panaxynol, falcarindiol, 8-O-acetylfalcarindiol, and (9Z)-1,9-heptadecadiene-4,6-diyne-3,8,11-triol), eight coumarins (osthol, isoimperatorin, scopoletin, byakangelicin, xanthotoxin, bergapten, oxypeucedanin methanolate, and oxypeucedanin hydrate), and two chromones (3'-O-acetylhamaudol, and hamaudol). The structures of the new isolates were determined based on spectral evidence. The ED50 of isolates against MK-1, HeLa, and B16F10 cell lines are reported.

Animals↗

PubMed1999

Chronic hepatitis in interferon-gamma transgenic mice is associated with elevated CPP32-like activity and interleukin-1beta-converting enzyme activity suppression.

Interferon-gamma (IFN-gamma) transgenic mice strongly express IFN-gamma in the liver and develop chronic hepatitis. Furthermore, hepatocyte apoptosis was shown by the TdT-mediated dUTP-biotin nick endlabeling method. In the present study, interleukin-1beta-converting enzyme (ICE) and CPP32-like protease activities in the liver of IFN-gamma transgenic mice were measured, using the synthetic substrates Ac-YVAD-MCA and Ac-DEVD-MCA. Plasma aspartate aminotransferase and alanine aminotransferase activities as well as CPP32-like activity were significantly elevated, while ICE activity was significantly reduced. The addition of the ICE inhibitor Ac-YVAD-CHO to IFN-gamma transgenic mouse liver cell cytosol had no effect on the CPP32 activity, in contrast to a CPP32 inhibitor. The present results indicate that chronic hepatitis in the IFN-gamma transgenic mouse is associated with a decrease in ICE and induction of CPP32-like activity.

Alanine Transaminase↗

PubMed1999

Herpesvirus infection in tortoises (Malacochersus tornieri and Testudo horsfieldii).

Large numbers of pancake tortoises (Malacochersus tornieri) and Horsfield tortoises (Testudo horsfieldii) in three consignments imported into Japan died soon after arrival. Some tortoises in the first consignment were dead on arrival. Postmortem examination of two of the pancake tortoises and four of the Horsfield tortoises revealed necrotizing lesions of the oral mucosa in both species, primarily in the tongue. Eosinophilic to amphophilic inclusion bodies were visible in the nuclei of mucosal epithelial cells in the lesions. Similar inclusion bodies were observed in the liver, spleen, adrenal glands, stomach, lungs, kidneys, small and large intestines, pancreas, and cerebrum of the pancake tortoises and in the liver, spleen, and pancreas of the Horsfield tortoises. Electron microscopic examination of the cells containing inclusion bodies showed herpesvirus-like particles about 100 nm in diameter in the cytoplasm. Nested polymerase chain reaction analysis using a herpesvirus consensus primer method confirmed the presence of a characteristic herpesvirus base sequence in tissue from these lesions.

Animals↗

PubMed1999

Idiopathic verapamil-sensitive left ventricular tachycardia complicated by right ventricular outflow tract ventricular tachycardia and ventricular fibrillation.

Idiopathic ventricular tachycardias (VTs) are generally divided into those arising from the right ventricle and those arising from the left ventricle. There has been few reports of two morphologically distinct VT occurring in patients with no apparent structural heart disease. We report a patient with verapamil-sensitive left VT with a right bundle branch block pattern that spontaneously changed to VT with a left bundle branch block pattern. Ventricular fibrillation was induced by the application of programmed stimulation. Although it is unclear if our patient with pleomorphic VT has ventricular vulnerability, it is necessary to investigate further and follow him carefully.

Adult↗

PubMed1999

Comparative genomic hybridization defines frequent loss on 16p in human anaplastic thyroid carcinoma.

Anaplastic thyroid cancer (ATC) is one of the malignant tumors with the poor prognosis that is thought to arise from well-differentiated thyroid cancer (DTC). To investigate the molecular mechanism of ATC, we studied genomic alterations of eight ATC cell lines and three DTC cell lines by means of the comparative genomic hybridization (CGH) method. Loss of 16p was observed in five of eight ATC cell lines (62. 5%), but none of the three DTC cell lines showed loss of this chromosome arm. It is notable that loss of 18q [7/8 of ATC (87.5%), 2/3 of DTC (67%)] and gain of 20q [5/8 of ATC (62.5%), 3/3 of DTC (100%)] were frequently seen in both histologic types. Our results suggest that there is a gene in 16p that is closely associated with transformation from well-differentiated thyroid cancer to anaplastic cancer.

Carcinoma↗

PubMed1999

Prognostic significance of clinical parameters and biological markers in patients with squamous cell carcinoma of the head and neck treated with concurrent chemoradiotherapy.

Concurrent chemoradiotherapy is reported to have a fair clinical outcome with organ preservation for patients with squamous cell carcinoma of the head and neck (SCCHN). The aim of this study was to determine whether biological markers are related to proliferative activity or apoptosis of tumor cells and whether clinical factors are associated with a clinical outcome in SCCHN patients treated with concurrent chemoradiotherapy. Immunostaining with antibodies specific for p53, bcl-2, bax, and MIB-1 was performed to evaluate expression of these proteins in formalin-fixed, paraffin-embedded specimens of 111 SCCHN patients treated with concurrent chemoradiotherapy (carboplatin, 100 mg/m2, four to six times every week; total radiation therapy dose of 40-65 Gy over 4-6.5 weeks). Multivariate analysis indicated that nodal status was a significant indicator of overall survival (OS; P = 0.001) and locoregional control (LRC; P = 0.002). In a univariate analysis, patients with a low MIB-1-positive index (< 40%) had better OS than those with a high MIB-1-positive index (> or = 40%; P = 0.013), although the difference was not statistically significant in a multivariate analysis (P = 0.060). Patients with bcl-2-positive tumors had better LRC than those with bcl-2-negative tumors, based on a multivariate analysis (P = 0.017). No statistically significant association was found between p53 or bax expression and clinical outcome. These results indicate that nodal status is the major prognostic factor in SCCHN patients treated with concurrent chemoradiotherapy. In addition, our findings suggest that bcl-2 positivity is associated with better LRC and that the proliferative activity of tumor cells might be prognostic for OS.

Antigens, Nuclear↗

PubMed1999

[The present and future of the pulmonary function tests. The relationship between respiratory and non-respiratory function].

Pulmonary function is classified as respiratory and non-respiratory function. Respiratory pulmonary function involves exchange of O2 and CO2 gas at alveolar units in the lung and non-respiratory pulmonary function concerns metabolism of enzymes, hormones, surfactants vaso-active substances and immunological factors in the lung. The purpose of this study was to examine the relationship between respiratory and non-respiratory function using our newly developed expired NO gas continuous analytic method and the calculation method of ventilatory energy of the lung. Furthermore, we analyzed the relationship between arterial blood O2 pressure (PaO2) and mitochondrial function.

Humans↗

PubMed1999

Respiratory impedance during positive expiratory airway pressure in patients with chronic obstructive pulmonary disease.

The effect of positive airway pressure (5.0 hPa) on airway impedance (Za) and tissue impedance (Zt) during the expiratory phase in chronic obstructive pulmonary disease (COPD) patients was evaluated using random noise oscillation and a body box method. The results were then compared with those obtained from normal subjects. In normal subjects, there was no significant difference between non-expiratory positive pressure (NPEP) and positive expiratory pressure (PEP) for the Zar (real part) and Zai (imaginary part) at 10 Hz (Zar NPEP: 2.14 +/- 0.76, PEP: 1.96 +/- 0.79; Zai NPEP: 1.42 +/- 0.66, PEP: 1.40 +/- 0.70 hPa l-1 s). However, in COPD patients, Zar decreased significantly and the Zai increased significantly during PEP as compared to the values during NPEP (Zar NPEP: 7.10 +/- 1.88, PEP: 5.97 +/- 1.67, P < 0.05; Zai NPEP: -4.10 +/- 2.27, PEP: -2.99 +/- 2.62 hPa l-1 s, P < 0.05). These results suggested that both central and peripheral airway resistance decreased during PEP in COPD patients. Tissue compliance (Ct) calculated from the Zt increased significantly during PEP as compared to during NPEP, in both normal subjects and in COPD patients (normal NPEP: 0.024 +/- 0.004, PEP: 0.021 +/- 0.003, P < 0.05; COPD NPEP: 0.024 +/- 0.004, PEP: 0.014 +/- 0.004 l hPa-1, P < 0.001). This may have been indicative of the stiffened chest wall during PEP.

Adult↗

PubMed1999

[Syphilitic orchitis: a case report].

Syphilitic orchitis is recently a rare disease in Japan. A 75-year-old man was referred to our hospital with the complaint of persistent swelling of the left scrotal contents in spite of prior antibiotic therapy. We suspected a testicular tumor because of lack of pain, and performed high orchiectomy. The specimen showed wide-ranged necrosis with a non-specific inflammatory change of the testis on hematoxylin-eosin stain. After performing analysis using a polymerase chain reaction method, we reached the final diagnosis of syphilitic orchitis.

Aged↗