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Exchange of erythrocyte intracellular (i/c) K+for extracellular (e/c) Na+in human erythrocytes treated with sub-CMC concentrations of the non-ionic detergent Brij 58 can be stopped by reincubation in serum or albumin containing solutions. The progressive equilibration of the K+contents of detergent-treated human erythrocytes with the incubation medium was reversed by an albumin-mediated withdrawal of detergent molecules from the cell. Re-establishment of near normal [K+] in terms of K+/kg water proceeds in two ways: (i) a metabolism-dependent net accumulation of K+ions; and (ii) a metabolism-independent shrinkage of erythrocytes, this being the more significant factor.  相似文献   
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In recent years, several genome‐wide association studies have identified candidate regions for genetic susceptibility in major mood disorders. Most notable are regions in a locus in chromosome 3p21, encompassing the genes NEK4‐ITIH1‐ITIH3‐ITIH4. Three of these genes represent heavy chains of the composite protein inter‐α‐inhibitor (IαI). In order to further establish associations of these genes with mood disorders, we evaluated behavioral phenotypes in mice deficient in either Ambp/bikunin, which is necessary for functional ITIH1 and ITIH3 complexes, or in Itih4, the gene encoding the heavy chain Itih4. We found that loss of Itih4 had no effect on the behaviors tested, but loss of Ambp/bikunin led to increased anxiety‐like behavior in the light/dark and open field tests and reduced exploratory activity in the elevated plus maze, light/dark preference and open field tests. Ambp/bikunin knockout mice also exhibited a sex‐dependent exaggeration of acoustic startle responses, alterations in social approach during a three‐chamber choice test, and an elevated fear conditioning response. These results provide experimental support for the role of ITIH1/ITIH3 in the development of mood disorders.  相似文献   
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Diffuse reflectance spectroscopy (DRS) is a noninvasive, fast, and low‐cost technology with potential to assist cancer diagnosis. The goal of this study was to test the capability of our physiological model, a computational Monte Carlo lookup table inverse model, for nonmelanoma skin cancer diagnosis. We applied this model on a clinical DRS dataset to extract scattering parameters, blood volume fraction, oxygen saturation and vessel radius. We found that the model was able to capture physiological information relevant to skin cancer. We used the extracted parameters to classify (basal cell carcinoma [BCC], squamous cell carcinoma [SCC]) vs actinic keratosis (AK) and (BCC, SCC, AK) vs normal. The area under the receiver operating characteristic curve achieved by the classifiers trained on the parameters extracted using the physiological model is comparable to that of classifiers trained on features extracted via Principal Component Analysis. Our findings suggest that DRS can reveal physiologic characteristics of skin and this physiologic model offers greater flexibility for diagnosing skin cancer than a pure statistical analysis. Physiological parameters extracted from diffuse reflectance spectra data for nonmelanoma skin cancer diagnosis.  相似文献   
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Insulin-like growth factor receptor (IGF-1R) is a growth factor receptor tyrosine kinase that acts as a critical mediator of cell proliferation and survival. Inhibitors of this receptor are believed to provide a new target in cancer therapy. We previously reported an isoquinolinedione series of IGF-1R inhibitors. Now we have identified a series of 3-cyanoquinoline compounds that are low nanomolar inhibitors of IGF-1R. The strategies, synthesis, and SAR behind the cyanoquinoline scaffold will be discussed.  相似文献   
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Background  

Hydrophobic protein from soybean (HPS) is an 8 kD cysteine-rich polypeptide that causes asthma in persons allergic to soybean dust. HPS is synthesized in the pod endocarp and deposited on the seed surface during development. Past evidence suggests that the protein may mediate the adherence or dehiscence of endocarp tissues during maturation and affect the lustre, or glossiness of the seed surface.  相似文献   
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This study, conducted in mesocosms, natural field sites, and in laboratory aquaria, showed that eutrophication altered the nutrient status and dominance patterns among marine macroalgae, which in turn, stimulated gammaridean density. Gammaridean abundance correlated positively with both nutrient addition and the amount of green algae (also stimulated by nutrient enrichment). Path analysis indicated that the direct effect of nutrients on gammaridean density was of less importance than the indirect effect through increased production of green algae. In cage colonisation experiments, either in the field or in a control mesocosm kept under ambient nutrient conditions, more gammarids colonised nutrient enriched algae (E-algae) than algae with ambient nutrient levels (A-algae). Gammarus locusta generally grew faster on nutrient enriched algal specimens and when reared on green rather than on brown algae (fucoids). The nutrient status of periphytic algae did not affect gammaridean growth significantly, but the number of egg-carrying females (and thus egg production) was significantly higher among gammarids reared on E-periphyton. The gammaridean habitat preference order (red > green > brown > periphyton) was almost the reverse of their growth rate in feeding assays (periphyton > green > brown). This implies that macroalgae may be more important as a habitat than as a food source for these animals, which then have to become mobile in search of optimal food items. In this process, algal nutrient content was important as the gammarids in our study actively chose high quality nutrient-rich food, which, in addition, increased their fitness. Stimulated growth rates and egg production may ultimately lead to population increase, which, combined with the preference for high nutrient food items may dampen the initial effect of nutrient enrichment (i.e. blooms of green macroalgae) in shallow coastal waters.  相似文献   
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Integrin CD11b/CD18 is a key adhesion receptor that mediates leukocyte migration and immune functions. Leukadherin-1 (LA1) is a small molecule agonist that enhances CD11b/CD18-dependent cell adhesion to its ligand ICAM-1. Here, we used single-molecule force spectroscopy to investigate the biophysical mechanism by which LA1-activated CD11b/CD18 mediates leukocyte adhesion. Between the two distinct populations of CD11b/CD18:ICAM-1 complex that participate in cell adhesion, the cytoskeleton(CSK)-anchored elastic elements and the membrane tethers, we found that LA1 enhanced binding of CD11b/CD18 on K562 cells to ICAM-1 via the formation of long membrane tethers, whereas Mn2+ additionally increased ICAM-1 binding via CSK-anchored bonds. LA1 activated wild-type and LFA1−/− neutrophils also showed longer detachment distances and time from ICAM-1-coated atomic force microscopy tips, but significantly lower detachment force, as compared to the Mn2+-activated cells, confirming that LA1 primarily increased membrane-tether bonds to enhance CD11b/CD18:ICAM-1 binding, whereas Mn2+ induced additional CSK-anchored bond formation. The results suggest that the two types of agonists differentially activate integrins and couple them to the cellular machinery, providing what we feel are new insights into signal mechanotransduction by such agents.  相似文献   
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