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1.
Abstract: Cardiopulmonary support (CPS) requires durability of the oxygenator. The life span of the oxygenator is affected by various clinical factors, including patient condition, perfusion condition, and equipment usage. Predictors for the durability of oxygenators were evaluated clinically in this study. Thirty-two patients, who had undergone CPS during the last 3 years in our institute were assigned to this study. Fifty oxygenators had been used (Capiox SX in 19, CB Maxima in 23, and AL-6000 in 8). Significant predictors for the durability of oxygenators were evaluated by nonparametric survival analysis and proportional hazards regression analysis. Univariate regression analysis revealed 6 significant predictors for the life span of oxygenators. These were the oxygenator type, type of centrifugal pump, acidosis with blood pH less than 7.35, base excess less than -5, blood glutamic-oxaloacetic transaminase (GOT) levels greater than 1,000 IU, and blood lactate dehydrogenase (LDH) levels greater than 3,000 IU. After multivariate analysis, there remained only 2 significant predictors. An oxygenator used with a noncoated CPS system (Capiox SX with Capiox EBS) proved to have a significantly shorter life span than one used with a heparin-coated system (CB Maxima or AL-6000 with CB BP-80) (hazards ratio, 3.588, p = 0.0065). Patient conditions, which revealed acidosis with less than -5 of base excess, significantly shortened the life of the oxygenator (hazards ratio, 3.595, p = 0.0188).  相似文献   
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E Wada  A Urisu  Y Kondo  F Horiba  M Tsuruta  T Yasaki  S Masuda  K Yamada  T Kozawa  Y Hida 《Arerugī》1991,40(12):1493-1499
IgE-mediated mechanisms are important in immediate hypersensitive reactions (IHR) to buckwheat. However, a part of subjects with high IgE for buckwheat show no IHR to buckwheat ingestion. Inspite of cross-allergenicity between buckwheat and rice, rice ingestion rarely induces IHR even in subjects with high IgE for rice unlike buckwheat-induced IHR. We speculated that there were some relationships between the presence of IHR to buckwheat and recognition of cross-allergenic determinants on buckwheat components with rice components. We examined IgE-RAST for rice in 58 subjects with positive IgE-RAST for buckwheat. IgE-RAST for Dermatophagoides pteronyssinus (Dp), egg white and cow's milk as unrelated antigens with rice were also assessed for a comparison. Subjects (n = 33) without IHR to buckwheat showed higher IgE-RAST values for rice than those (n = 25) with IHR, whereas there were no differences in IgE-RAST values for Dp, egg white and cow's milk between two groups with and without IHR. IgE-RAST values for buckwheat showed significant close correlations to those for rice in subjects without IHR to buckwheat but not in those with IHR. There were no significant correlations between IgE-RAST values for buckwheat and for Dp, egg white or cow's milk in both groups with and without IHR. These results suggested that the IgE from subjects without IHR to buckwheat recognized cross-allergenic determinants with rice on the buckwheat components.  相似文献   
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Microglia accumulation at the site of amyloid plaques is a strong indication that microglia play a major role in Alzheimer's disease pathogenesis. However, how microglia affect amyloid-beta peptide (Abeta) deposition remains poorly understood. To address this question, we developed a novel bigenic mouse that overexpresses both amyloid precursor protein (APP) and monocyte chemotactic protein-1 (MCP-1; CCL2 in systematic nomenclature). CCL2 expression, driven by the glial fibrillary acidic protein promoter, induced mononuclear phagocyte (MP; monocyte-derived macrophage and microglial) accumulation in the brain. When APP/CCL2 transgenic mice were compared to APP mice, a fivefold increase in Abeta deposition was present despite increased MP accumulation around hippocampal and cortical amyloid plaques. Levels of full-length APP, its C-terminal fragment, and Abeta-degrading enzymes (insulin-degrading enzyme and neprilysin) in APP/CCL2 and APP mice were indistinguishable. Sodium dodecyl sulfate-insoluble Abeta (an indicator of fibrillar Abeta) was increased in APP/CCL2 mice at 5 months of age. Apolipoprotein E, which enhances Abeta deposition, was also increased (2.2-fold) in aged APP/CCL2 as compared to APP mice. We propose that although CCL2 stimulates MP accumulation, it increases Abeta deposition by reducing Abeta clearance through increased apolipoprotein E expression. Understanding the mechanisms underlying these events could be used to modulate microglial function in Alzheimer's disease and positively affect disease outcomes.  相似文献   
6.
Summary The autopsy findings in a pancreatoblastoma in a 7-year-old Japanese girl is reported. The tumour was in the head and body of the pancreas, and was associated with diffuse carcinomatous peritonitis and hepatic and pulmonary metastases. There was marked elevation (more than 10000 ng/ml) of serum alpha-fetoprotein (AFP). Histopathologically the tumour was composed of solid epithelial elements with fibrous stroma, showing acinar arrangement, squamoid clusters and tubular structures. The epithelial elements contained numerous fine PAS positive granules in the cytoplasm. Immunocytochemical results suggested epithelial differentiation with positivity to alpha-1-antitrypsin (AAT), keratin, CA19-9, and AFP. No endocrine elements were recognized. Characteristic feature of this tumour are discussed and compared with prevoius reports.  相似文献   
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Metalloproteinases and their inhibitors are known to play an important role in the extracellular matrix remodeling associated with preinvasive lesions and invasive carcinomas; however, little is known about their role in early lung carcinoma. Immunohistochemical studies were made of the reactivity of bronchial squamous preneoplastic lesions from cigarette smokers, including basal cell hyperplasia, squamous metaplasia, dysplasia, carcinoma in situ, and invasive squamous cell carcinoma for matrix metalloproteinases (MMPs), their tissue inhibitors (TIMPs), and type IV collagen in 13 patients. Staining for type IV collagen disclosed discontinuities in basement membranes from basal cell hyperplasia to dysplasia, progressing to destruction in carcinoma in situ and invasive carcinoma. Reactivity for MMP-9 was mild in basal cell hyperplasia and squamous metaplasia, increasing in carcinoma in situ and invasive carcinoma. In contrast, reactivity for MMP-1 was strong in basal cell hyperplasia and squamous metaplasia, decreasing in carcinoma in situ and invasive carcinoma. Some neoplastic cells in carcinoma in situ and invasive carcinoma were MMP-3 positive. Staining for MMP-2 and TIMP-1 was moderate to strong in all squamous preinvasive lesions. Confocal microscopy showed MMP-9-positive cells passing through fragmented basement membranes in which type IV collagen and MMP-9 were colocalized. Type IV collagen colocalized with MMP-2 in all lesions and with TIMP-1 in basal cell hyperplasia and squamous metaplasia. The inverse relationships between the reactivity for MMP-1 and MMP-9 with progression of bronchial squamous preinvasive lesions suggest important roles for these MMPs in basement membrane remodeling in these lesions.  相似文献   
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Ebselen prevents noise-induced excitotoxicity and temporary threshold shift   总被引:1,自引:0,他引:1  
This investigation tested the hypothesis that a noise-induced temporary threshold shift (TTS) can be attenuated by a peroxynitrite scavenger, ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one). Guinea pigs received an oral dose of the vehicle or 10 mg/kg ebselen 1 h before exposure to 115 dB SPL 4-kHz octave band noise for 3 h. In controls, auditory brainstem response (ABR) thresholds increased by 25–45 dB immediately after noise and returned to pre-exposure baseline thresholds 7 days later. Ebselen eliminated this ABR threshold shift following noise exposure. In controls, swelling of the afferent dendrites beneath the inner hair cells was evident immediately after noise, whereas ebselen significantly reduced this pathology. These findings suggest that scavenging peroxynitrite can attenuate noise-induced excitotoxicity and, thereby, TTS.  相似文献   
9.
The allergenic activity of Rice protein 16 KD (RP16KD) isolated from water soluble rice proteins was examined by radioallergosorbent test (RAST), RAST inhibition and histamine release assay. All of the 31 sera which showed positive RAST values for rice grain extract were positive for RP16KD RAST. Furthermore, there was a significant correlation (r = 0.56, p less than 0.01) between these RAST values. PR16KD effectively inhibited IgE binding to the rice grain extract disc in RAST inhibition assays using 4 sera with positive RAST values for both antigens. In 17 subjects with positive RAST values for rice grain extract, a significant positive correlation (r = 0.53, p less than 0.05) was found between the maximum percent histamine releases from their leukocytes by rice grain extract and RP16KD. These data strongly suggest that RP16KD is one of the major allergens of rice grain.  相似文献   
10.
Although the prostate gland is a rich source of α1-adreno- (α1-AR) and m1-cholino receptors (m1-AChR), the membrane processes associated with their activation in glandular epithelial cells is poorly understood. We used the whole-cell patch-clamp technique to show that the agonists of the respective receptors, phenylephrine (PHE) and carbachol (CCh), activate cationic membrane currents in lymph node carcinoma of the prostate (LNCaP) human prostate cancer epithelial cells, which are not dependent on the filling status of intracellular IP3-sensitive Ca2+ stores, but directly gated by diacylglycerol (DAG), as evidenced by the ability of its membrane permeable analogue, OAG, to mimic the effects of the agonists. The underlying cationic channels are characterized by the weak field-strength Eisenman IV permeability sequence for monovalent cations ( P K(25) > P Cs(4.6) > P Li(1.4) > P Na(1.0)), and the following permeability sequence for divalent cations: P Ca(1.0) > P Mg(0.74) > P Ba(0.6) > P Sr(0.36) > P Mn(0.3). They are 4.3 times more permeable to Ca2+ than Na+ and more sensitive to the inhibitor 2-APB than SK&F 96365. RT-PCR analysis shows that DAG-gated members of the transient receptor potential (TRP) channel family, including TRPC1 and TRPC3, are present in LNCaP cells. We conclude that, in prostate cancer epithelial cells, α1-ARs and m1-AChRs are functionally coupled to Ca2+-permeable DAG-gated cationic channels, for which TRPC1 and TRPC3 are the most likely candidates.  相似文献   
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