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131.
Antisense oligodeoxynucleotides against thrombomodulin suppress the cell growth of lung adenocarcinoma cell line A549 总被引:2,自引:0,他引:2
Thrombomodulin (TM), an anticoagulant factor on endothelial cells, is known to be expressed in non-endothelial cells as well. In neoplastic cells of lung adenocarcinomas, TM is expressed but its correlation with growth potential has not been studied. As TM expression has a negative correlation with cell proliferation in lung squamous cell carcinomas, we examined its growth effect on lung adenocarcinoma cells of the A549 cell line by inhibiting TM expression with antisense oligodeoxynucleotides (ODN). In the antisense ODN transfected cells, the expression of TM mRNA was decreased to 49% at 12 h and 47% at 24 h, which was in accordance with TM expression at the protein level. By IdU (5-iodo-2'-deoxyuridine) incorporation assay, the growth of A549 cells was found to have decreased to 36% of the control level at 24 h post-transfection. The suppression of cell growth was maintained in a concentration-dependent manner for 48 h after transfection, when the expression of TM started to rebound. In the transfected cells, the G1 phase cell count was reduced to 60.7%, compared with 68.2% in the control transfectants. These results suggest that TM expression may play a suppressive role in the proliferation activity of A549 lung adenocarcinoma cells. 相似文献
132.
Hypoxia-ischemic insult in neonatal rats induced slowly progressive brain damage related to memory impairment 总被引:4,自引:0,他引:4
Mishima K Ikeda T Aoo N Takai N Takahashi S Egashira N Ikenoue T Iwasaki K Fujiwara M 《Neuroscience letters》2005,376(3):194-199
The present study was designed to determine potential associations between the brain damage induced by hypoxic-ischemic (HI) insult and spatial learning impairment in an eight-arm radial maze task. We first determined the pathological outcomes after 2, 5, 9, and 17 weeks of recovery following the HI insult. The results show that the brain damage progressed from 2 up to 17 weeks of recovery. To clarify the time course of the brain damage changes, we investigated the histological changes of the same individual with magnetic resonance imaging (MRI) after 5, 9, and 57 weeks of recovery following the HI insult. The MRI changes were similar to the histological changes, and the brain damages were exacerbated in the contralateral hemisphere after 57 weeks of recovery following the HI insult. To investigate whether alteration in brain function was correlated with MRI and histological changes, the rats were made to find their way through an eight-arm radial maze was performed at either 7th or 16th weeks of recovery. According to the results, the spatial learning impairments of rats in the maze starting at 16 weeks of recovery were more severe than those at 7 weeks of recovery, indicating that the impairments were progressive and depended on the degree of brain damage. The results of the present study are the first demonstration that the evolutional and specific brain damage following the HI insult is slowly and progressively exacerbated to the contralateral hemisphere and rats who experience the HI are at risk for showing a late impairment of brain function. 相似文献
133.
Summary Based on national mortality data, the frequency of hip fractures in elderly people was compared between Switzerland and Japan. Age-adjusted annual incidence rates per 100 000 population estimated for Swiss persons over 60 years were around 150 and 200 in males and around 450 in females, while for the Japanese they were only 132 in males and 285 in females. Age-adjusted death rates from hip fracture for the Swiss over 60 were 20.0 in males and 28.9 in females, while for the Japanese they were only 1.6 in males and 2.7 in females. The inclination of the age-dependent slope in hip fracture mortality rates was substantially the same in both countries, but there was a lag time of approximately 10 years in Japan. Remarkably, the proportion of deaths due to falls among all accidental deaths was several times greater in both sexes for the Swiss than for the Japanese. This differential might be an important underlying reason for the observed difference between death rates of hip fracture in Switzerland and Japan. Other known behavioral risk factors for hip fracture such as diet, exercise, estrogen use etc. are unlikely to explain the observed difference in hip fracture mortality and morbidity between Switzerland and Japan. However, given the doubts on the reliability and thus comparability of the available data on mortality and morbidity, the present findings should be regarded as preliminary. In conclusion, we believe that the unexplained and large difference in the burden of hip fracture between Switzerland and Japan merits further studies, including new aetiological hypotheses.
Zusammenfassung Gestützt auf nationale Sterbedaten wird die Häufigkeit von Hüftfrakturen bei Betagten in der Schweiz und Japan verglichen. Alterskorrigierte jährliche Inzidenzraten (bezogen auf 100 000 Einwohner) bezifferten sich bei den Schweizer Personen über 60 Jahren auf ca. 150–200 bei den Männern sowie ca. 450 bei den Frauen, während bei den Japanern die entsprechenden Inzidenzen lediglich 132 bei den Männern und 285 bei den Frauen betrugen. Die alterskorrigierte durch Hüftfrakturen bedinte Mortalität (pro 100000) betrug bei den Schweizern über 60 Jahren 20,0 bei den Männern und 28,9 bei den Frauen, während bei den Japanern die entsprechenden Werte bei 1,6 für Männer und 2,7 für Frauen lagen. Die Gerade, die das Verhältnis zwischen Alter und Hüftfraktur-Mortalität charakterisiert, zeigte in beiden Ländern ungefähr die gleiche Steigung, war in Japan jedoch um ca. 10 Jahre rechtsverschoben. Bemerkenswerterweise war der Anteil sturzbedingter Todesfälle unter allen unfallbedingten Todesfällen bei beiden Geschlechtern in der Schweiz wesentlich höher als in Japan. Dieser Unterschied könnte eine wichtige, zurgrundeliegende Ursache für die Differenz in der Hüftfrakturmortalität zwischen der Schweiz und Japan darstellen. Andere verhaltensabhängige Risikofaktoren für Hüftfraktur wie Ernährung, körperliche Bewegung, Oestrogenzufuhr usw. vermögen die beobachteten Unterschiede in der Mortalität und Morbidität an Hüftfraktur zwischen der Schweiz und Japan kaum zu erklären Angesichts der ungewissen Reliabilität und Vergleichbarkeit der zur Verfügung stehenden Daten müssen die vorliegenden Ergebnisse allerdings mit Vorsicht interpretiert werden. Zusammenfassend glauben wir, dass der grosse und weitgehend unerklärte schweizerisch-japanische Unterschied im Auftreten von Hüftfrakturen weiter abgeklärt werden sollte, unter Einschluss neuer ätiologischer Hypothesen.
Résumé Basée sur les données de mortalité nationales, la fréquence des fractures de hanche des personnes âgées est comparée entre la Suisse et le Japon. Les taux d'incidence annuels corrigés pour l'effet de l'âge chez les personnes suisses âgées de plus de 60 ans sont d'environ 150–200 chez les hommes (par rapport à 100 000 habitants), ainsi qu'environ 450 chez les femmes, tandis qu'au Japon les incidences correspondantes s'élèvent à 132 chez les hommes et 285 chez les femmes. La mortalité des fractures de hanche, corrigée pour l'effet de l'âge s'élève chez les Suisses âgés de plus de 60 ans à 20,0 (par 100 000) chez les hommes et à 28,9 chez les femmes, alors que chez les Japonais les taux correspondants sont 1,6 chez les hommes et 2,7 chez les femmes. La proportion de décès faisant suite à des chutes parmi l'ensemble des accidents mortels est remarquablement plus élevée en Suisse qu'au Japon, pour les femmes comme pour les hommes. Cette différence pourrait expliquer le taux élvé de décès suite à une fracture de hanche observé en Suisse. D'autres facteurs de risque pour la fracture de hanche liés au style de vie ne sont apparemment pas en mesure d'expliquer les différences de mortalité et de morbidité par fracture de hanche observées entre la Suisse et le Japon. Face aux doutes qui concernent la fiabilité et la comparabilité des données à disposition, ces résultats doivent être interprétés avec prudence. Toutefois, nous pensons que la différence substantielle des taux de fractures de hanche entre Suisse et Japon, qui reste inexpliquée, devrait être examinée plus en détail, également en ce qui concerne de nouvelles hypothèses étiologiques.相似文献
134.
Sakuragi T Fujiwara K Akashi-Tanaka S Tsuda H Fukutomi T 《Breast cancer (Tokyo, Japan)》1997,4(1):53-56
Dermatofibrosarcoma protuberans (DFSP) is a slow-growing but locally aggressive, fibrous tumor that has a high rate of local
recurrence after surgical resection. This tumor occurs most commonly in the trunk and proximal extremities. In this report
we present a case of dermatofibrosarcoma protuberans in the skin over the breast which was re-excised after pathological diagnosis,
considering cosmetic aspects. Only three other cases of dermatofibrosarcoma protuberans of the anterior chest wall have been
encountered in our hospital, and all of these cases were male. The presence of this tumor in the skin over the breast appears
to be rare in females. Careful complete resection is recommended for this type of tumor. 相似文献
135.
Arai T Yasuda Y Takaya T Yoshimi N Ito H Fujiwara H 《International journal of oncology》1997,11(1):127-131
136.
Ohno A Hirashima T Kubo A Masuda N Takada M Fujiwara H Yasumitsu T Kikui M Fukuoka M Nakagawa K 《International journal of oncology》1997,10(3):521-528
To investigate the role of p53 abnormalities in predicting the survival of patients with non-small cell lung cancer (NSCLC), polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and immunohistochemical analyses were performed on 74 and 67 tumor samples, respectively, from patients with pathological stage I-IIIa NSCLC. An abnormally migrating SSCP band was observed in 21 of 74 (28%) tumor specimens. DNA sequence analysis revealed 23 intragenic mutations including 3 small deletions and 20 point mutations. Immunohistochemical analysis using the DO-7 monoclonal antibody showed abnormal expression of p53 in 27 of 67 (40%) patients. The concordance rate between immunohistochemical and PCRSSCP analyses was 73% (49/67) in this study. Univariate and multivariate analyses demonstrated that abnormal expression of p53 may be associated with prolonged survival (p=0.0997 and 0.0099, respectively). In contrast, no relationship was observed between p53 mutation and overall survival (0.6968). These results suggest that p53 status and the survival outcome changes between immunohistochemical and mutational analyses in stage I-IIIa NSCLC. 相似文献
137.
Shuzo Oshita Yoshiki Fujiwara Hisashi Tamura Takefumi Sakabe Hiroshi Takeshita 《Journal canadien d'anesthésie》1994,41(6):534-541
To gain a better understanding of the direct actions of halothane on myocardial function in ischaemia, we studied the effects
of increasing extracellular potassium concentration and decreasing extracellular pH (acidosis), alone or in combination with
halothane, on the contractile force and resting tension in isolated atria. Guinea pig left atria were superfused with Tyrode’s
solution and stimulated at 1 Hz. Isometric contractile force and resting tension were measured using a force displacement
transducer. Perfusate potassium concentrations were increased from 5.4 mmol · L−1 to either 8.1 mmol · L−1 or 10.8 mmol · L−1 by adding KCl to the standard Tyrode’s solution, and its pH was decreased from 7.4 to either 7.0 or 6.5 by decreasing bicarbonate.
In standard Tyrode’s solution (potassium 5.4 mmol · L−1, pH 7.4), halothane 0.5–2% reduced contractile force in a dose-dependent manner (P < 0.05); the effective concentration of
halothane for 50% inhibition of contractile force (IC50) was 1.3%. Both increasing extracellular potassium and decreasing extracellular pH decreased the contractile force in a potassium-or
pH-dependent fashion. The negative inotropism of halothane (1%) was not altered by increasing potassium concentrations, whereas
1% halothane caused a greater decrease in contractile force at pH 6.5 than at pH 7.4. Halothane (1%) enhanced the acidosis
(pH 6.5)-induced increases in resting tension. Arrhythmias were produced in one of eight preparations during acidosis, while
four of eight preparations demonstrated arrhythmias during acidosis in the presence of halothane. These data suggest that
acidosis and halothane may have a synergistic interaction on the contractile force and resting tension of the atria. The increase
in resting tension observed during acidosis/ halothane conditions suggests than an increase in cytosolic calcium is associated
with these synergistic interactions between acidosis and halothane.
Pour mieux comprendre l’action direct de l’halothane sur la fonction myocardique pendant l’ischémie, nous avons étudié les
effets de l’augmentation du potassium extracellulaire et de la diminution du pH extracellulaire (acidose), seuls ou en association
avec l’halothane, sur la force contractile et la tension de repos d’oreillettes isolées. Des oreillettes gauches de cobaye
furent perfusées avec une solution de Tyrode et stimulées à 1 Hz. La force contractile isométrique et la tension de repos
ont été mesurées avec un transducteur de force de déplacement. Les concentrations de potassium perfusées ont été augmentées
de 5,4 mmol · L−1 à 8,1 mmol · L−1 ou à 10,8 mmol · L−1 par l’ajout de KCl à la solution standard de Tyrode, et son pH abaissé de 7,4 à 7,0 ou 6,5 par baisse des bicarbonates. Avec
la solution standard de Tyrode (potassium 5,4 mmol · L−1, pH 7,4), l’halothane (0.5–2%) diminue la force contractile proportionnellement à la dose (P < 0,05); la concentration efficace
d’halothane requise pour produire une inhibition de 50% de la force contractile (IC5O) a été de 1,3%. L’augmentation du potassium extracellulaire et la diminution du pH extracellulaire réduisent toutes les deux
la force contractile proportionnellement au potassium ou au pH. L’inotropisme négatif de l’halothane (1%) n’est pas modifié
par l’augmentation de la concentration de potassium alors que l’halothane produit une diminution plus importante de la force
contractile à un pH de 6,5 que de 7,4. L’halothane (1%) exagère l’augmentation de la tension de repos induite par l’acidose
(pH 6,5). Des arrythmies sont apparues sur une des huit préparations pendant l’acidose en présence d’halothane. Ces données
suggèrent que l’acidose et l’halothane pourraient avoir une activité synergique sur le force contractile et la tension de
repos des oreillettes. L’augmentation de la tension de repos observée pendant l’acidose combinée à l’halothane suggère l’association
d’une augmentation du calcium cytosolique avec des interactions synergiques entre l’acidose et l’halothane. 相似文献
138.
M. -G. Martinoli J. Q. Trojanowski M. L. Schmidt S. E. Arnold T. M. Fujiwara V. M. -Y. Lee H. Hurtig J. -P. Julien C. Clark 《Acta neuropathologica》1995,90(3):239-243
Apolipoprotein E (APOE) is a lipoprotein expressed in liver and brain as one of three isoforms (APOE 2, APOE 3 and APOE 4). Recent findings suggest that the presence of APOE 4 is associated with an increased risk for both familial Alzheimer's disease and late-onset Alzheimer's disease. We extended these observations by determining the frequency of APOE alleles in patients with pathologically confirmed Alzheimer's Disease (AD), Parkinson's disease (PD), diffuse Lewy Body disease (DLBD), AD with concomitant PD pathology, demented PD patients without or with concomitant AD pathology and in schizophrenics with a progressive dementia (SCHIZ+DEM). The APOE genotype was determined by restriction digestion of polymerase chain reaction-amplified DNA isolated from frozen brain samples. The frequency of the APOE 4 allele was highest among sporadic AD and DLBD patients (0.30 and 0.38, respectively) and lowest in the SCHIZ+DEM and non-demented PD patients (0.06 and 0.1, respectively). Thus, the APOE 4 allele is over-represented selectively in patients with dementias associated with plaques and tangles and/or cortical Lewy bodies, but not in demented schizophrenics or non-demented PD patients. 相似文献
139.
BACKGROUND: The objective of this study was to evaluate the effects of isoflurane anesthesia on the pulmonary vascular responses to exogenous adenosine triphosphate-sensitive potassium (K+ ATP) channel activation and circulatory hypotension compared with responses measured in the conscious state. In addition, the extent to which K+ ATP channel inhibition modulates the pulmonary vascular response to circulatory hypotension in conscious and isoflurane-anesthetized dogs was assessed. METHODS: Fifteen conditioned, male mongrel dogs were fitted with instruments for long-term monitoring to measure the left pulmonary vascular pressure-flow relation. The dose-response relation to the K+ ATP channel agonist, lemakalim, and the pulmonary vascular response to circulatory hypotension were assessed in conscious and isoflurane-anesthetized (approximately 1.2 minimum alveolar concentration) dogs. The effect of the selective K+ ATP channel antagonist, glibenclamide, on the pulmonary vascular response to hypotension was also assessed in conscious and isoflurane-anesthetized dogs. RESULTS: Isoflurane had no effect on the baseline pulmonary circulation, but it attenuated (P<0.05) the pulmonary vasodilator response to lemakalim. Reducing the mean systemic arterial pressure to approximately 50 mm Hg resulted in pulmonary vasoconstriction (P<0.05) in the conscious state, and this response was attenuated (P<0.05) during isoflurane. Glibenclamide had no effect on the baseline pulmonary circulation, but it potentiated (P<0.05) the pulmonary vasoconstrictor response to hypotension in conscious and isoflurane-anesthetized dogs. CONCLUSIONS: These results indicate that K+ ATP-mediated pulmonary vasodilation and the pulmonary vasoconstrictor response to hypotension are attenuated during isoflurane anesthesia. Endogenous K+ ATP channel activation modulates the pulmonary vasoconstrictor response to hypotension in the conscious state, and this effect is preserved during isoflurane anesthesia. 相似文献
140.
Hirose M Hirose Y Gamou M Harigae M Fujiwara C 《Masui. The Japanese journal of anesthesiology》1999,48(1):48-52
We studied the effects of modified Calafiore technique that is intermittent antegrade warm blood cardioplegia including potassium solution and oxygenated with normothermic cardiopulmonary bypass. From January 1996 to March 1997, 45 patients who had undergone elective coronary artery bypass grafting were assigned retrospectively to two groups. Warm group: 25 patients received intermittent antegrade warm blood cardioplegia with normothermic cardiopulmonary bypass. Cold group: 20 patients received intermittent antegrade cold blood cardioplegia with slight hypothermic cardiopulmonary bypass. Preoperative variables were similar in both groups. The rate of sinus rebeating after aorta declamping with DC was lower in warm group than in cold group [warm group 2/25 (8%) versus cold group 8/20 (40%); P < 0.05]. The levels of CK and CK-MB were significantly lower in warm group than in cold group on postoperative day 0. On postoperative day 0 and day 1, the dosage of cathecholamines were significantly less for the warm group than in the cold group. Perioperative events of IABP, PMI and neurological dysfunction were not statistically different. These results show that intermittent antegrade warm blood cardioplegia is a safe and effective method for myocardial protection. But it requires further assessment. 相似文献