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261.
It is well established that the glomerular capillary wall consists of three layers: endothelial cell, glomerular basement membrane, and the slit diaphragm bridging foot processes of glomerular epithelial cell. Which structure in the glomerular capillary wall represents the primary filter for retaining plasma proteins is not clearly elucidated. An anti-slit diaphragm monoclonal antibody (mAb) 5-1-6 causes massive proteinuria in rats by single intravenous injection, which clearly indicates that the slit diaphragm plays a critical role for maintaining the barrier function of the glomerular capillary wall. Recently, we concluded that mAb 5-1-6 recognized a rat homolog of nephrin, a gene product of NPHS1. The expression of nephrin decreased in puromycin aminonucleoside nephropathy and adriamycin nephropathy as well as mAb 5-1-6-induced nephropathy, which suggested that nephrin was involved in the development of proteinuria in these proteinuric states. In mAb 5-1-6 nephropathy, the slit diaphragm was maintained morphologically normal, although nephrin expression dramatically decreased. The finding suggested that nephrin was not a sole component of the slit diaphragm. To better understand the structure of the slit diaphragm, it is particularly important to identify other components that build up the structure of the slit diaphragm together with nephrin.  相似文献   
262.
Psychological stress exacerbates mast cell (MC)-dependent inflammation, including nasal allergy, but the underlying mechanisms are not thoroughly understood. Because the key stress-mediating neurohormone, corticotropin-releasing hormone (CRH), induces human skin MC degranulation, we hypothesized that CRH may be a key player in stress-aggravated nasal allergy. In the current study, we probed this hypothesis in human nasal mucosa MCs (hM-MCs) in situ using nasal polyp organ culture and tested whether CRH is required for murine M-MC activation by perceived stress in vivo. CRH stimulation significantly increased the number of hM-MCs, stimulated both their degranulation and proliferation ex vivo, and increased stem cell factor (SCF) expression in human nasal mucosa epithelium. CRH also sensitized hM-MCs to further CRH stimulation and promoted a pro-inflammatory hM-MC phenotype. The CRH-induced increase in hM-MCs was mitigated by co-administration of CRH receptor type 1 (CRH-R1)-specific antagonist antalarmin, CRH-R1 small interfering RNA (siRNA), or SCF-neutralizing antibody. In vivo, restraint stress significantly increased the number and degranulation of murine M-MCs compared with sham-stressed mice. This effect was mitigated by intranasal antalarmin. Our data suggest that CRH is a major activator of hM-MC in nasal mucosa, in part via promoting SCF production, and that CRH-R1 antagonists such as antalarmin are promising candidate therapeutics for nasal mucosa neuroinflammation induced by perceived stress.  相似文献   
263.
The beta CK2tes gene encodes a new variant of the tissue-specific regulatory beta-subunit of casein kinase 2 (CK2). The beta CK2tes open reading frame comprises nucleotide stretches encoding for the conservative polypeptide motifs characteristic for the CK2 beta-subunit including the Glu/Asp rich region responsible for regulation of CK2, C-terminal fragment responsible for binding to the catalytic alpha-subunit, and "zinc finger" motif. Unlike conserved sequences of CK2 beta-subunits in other organisms the beta CK2tes polypeptide has no autophosphorylation site or other putative phosphorylation sites. beta CK2tes is expressed only in testes, whereas beta CK2 expression is maximal at embryonic stages and is detected also in larvae. We suggest that beta CK2tes determines substrate specificity of CK2 and/or CK2 activity during spermatogenesis in Drosophila.  相似文献   
264.
The purposes of this study are (a) to establish a measurement for evaluating conversational impressions of group discussions, and (b) to make an exploratory investigation on their interactional processes which may affect to form those impressions. The impression rating and factor analysis undertaken first give us four factors concerning conversational impressions of “focus group interviews (FGIs)”: conversational activeness, conversational sequencing, the attitudes of participants and the relationships of participants. In relation to the factors of conversational activeness and conversational sequencing in particular, the microanalysis of four selected topical scenes from our database further shows that the behavior of the moderator and the interviewees is organized not independently but with reference to each other. The study thus emphasizes the importance of the integration of quantitative and qualitative approaches towards human interactions.
Kana Suzuki (Corresponding author)Email: Email:
Ikuyo MorimotoEmail:
Etsuo MizukamiEmail:
Hiroko OtsukaEmail:
Hitoshi IsaharaEmail:
  相似文献   
265.
Amino-functional silanol surface are mostly used for the immobilization of inorganic ions, molecules, organic or biochemical molecules onto the mesopore surface. In analytical chemistry, the metal ion uptake was visualized through colorimetric sensors using chromophore molecules. One needs to know the structure-property correlation between the chromophore and silylating agent while choosing chromophore, which is very important to design the sensors. We have used two chromophores representative of hydrophobic and hydrophilic type. We used density functional calculation on all the interacting molecules in both the unsolvated phase and solvated medium within the domain of hard soft acid base principle (HSAB) to look at the localized activity of the interacting atoms of these reacting molecules to formulate a priori rule to choose of the best chromophore. We have as well postulated the mechanism of interaction between chromophore and the silylating agent. The results were compared with experiment and it is observed that solvation plays a detrimental role in the binding of chromophore with silylating agent. The results also show that, the range of reactivity index can be used as a suitable property to scale activity of chromophore molecules suitable for the sensing process. It is observed that the hydrophobic chromophore binds stronger with both the metal and the silylating agent; whereas for the hydrophilic one, it binds only with the silylating agent when solvated and in all cases the metal ion binding is weaker compared to that of the hydrophobic one.  相似文献   
266.
We present the solution to the algebraic Riccati equation (ARE) with indefinite sign quadratic term related to the H control problem for singularly perturbed systems by means of a Kleinman type algorithm. The resulting algorithm is very efficient from the numerical point of view because the ARE is solvable even if the quadratic term has an indefinite sign. Moreover, the resulting iterative algorithm is quadratically convergent. We also present an algorithm for solving the generalized algebraic Lyapunov equation on the basis of the fixed point algorithm  相似文献   
267.
268.
A new assembly method is described for easy construction of optical modules consisting of guide frames, spacer frames, and a housing frame. This method is used to assemble a two-dimensional optical-fiber collimator and a digital discrete correlator, which are fundamental parts of free-space optical computing systems. We show that a multistage optical system can be constructed simply by stacking of several optical functional blocks. Moreover, these compact modules do not need a conventional optical bench, they are compact, and assembly time is reduced. We demonstrated by experiment that the accuracy of optical modules assembled with this method is within the specifications of the optical system.  相似文献   
269.
Simultaneous dry removal of SO2 and NOx from flue gas has been investigated using a powder-particle fluidized bed. In a process of flue gas desulfurization by use of solid sorbents such as FeO (dust from a steel plant) and CuO, the smaller the particle size of sorbents, the higher the expected SO2 conversion. In a powder-particle fluidized bed (PPFB), fine particles less than 40 μm in diameter fed into the bed are fluidized with coarse particles. But only the fine particles are entrained from the bed, and their residence time in the bed is remarkably long.

The reduction of NOx with NH3 in the fluidized bed is catalyzed by coarse particles or both coarse and fine particles. In this study, PPFB was applied to simultaneous dry SO2/NOx removal process, and several kinds of sorbents or catalysts were evaluated in a PPFB. Using the selected sorbents and catalysts, kinetic measurements were made in the temperature range of 300 to 600°C. SO2 removal efficiencies were affected by reaction temperature, sorbent/S ratio, and static bed height. NOx removal efficiencies in excess of 95% were achieved at NH3/NOx mole ratio of 1.0. When FeO was used as sorbent, SO2 conversion increased with increasing temperature and reached 80% at 600°C.  相似文献   

270.
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