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51.
N S Magnuson L E Perryman C R Wyatt T Ishizaka P H Mason A E Namen K L Banks J A Magnuson 《Journal of immunology (Baltimore, Md. : 1950)》1984,133(5):2518-2524
Peripheral blood mononuclear cells (PBMC) from 14 foals with hereditary severe combined immunodeficiency (SCID) were studied to determine the extent of lymphocyte differentiation that occurs in this disorder. PBMC from all 14 horses had the morphologic characteristics of large granular lymphocytes (LGL). Cells from only one of 14 horses were responsive to phytolectin stimulation in a standard blastogenesis assay; however, PBMC from all 14 horses proliferated in continuous culture in the presence of partially purified interleukin 2. Furthermore, there were differences in the growth patterns of these cultured cells that correlated with their ability to respond to phytolectin stimulation. PBMC obtained from the 13 phytolectin-unresponsive foals survived in culture for only 4 to 5 wk, divided very slowly, developed large granules composed primarily of calcium phosphate, and accumulated high concentrations of histamine. In contrast, PBMC from the phytolectin-responsive SCID foal proliferated in continuous culture for over 100 days, divided as rapidly as normal equine PBMC under identical culture conditions, and did not accumulate granules or histamine. These observations indicate that lymphoid cell differentiation occurs in some horses with SCID even though the identity of the LGL is unresolved. Two possibilities are that LGL are products of a pathway separate from that of lymphocytes or that LGL are precursors of mature lymphocytes. 相似文献
52.
Multiphysics simulation of blood flow and LDL transport in a porohyperelastic arterial wall model 总被引:1,自引:0,他引:1
Atherosclerosis localizes at a bend andor bifurcation of an artery, and low density lipoproteins (LDL) accumulate in the intima. Hemodynamic factors are known to affect this localization and LDL accumulation, but the details of the process remain unknown. It is thought that the LDL concentration will be affected by the filtration flow, and that the velocity of this flow will be affected by deformation of the arterial wall. Thus, a coupled model of a blood flow and a deformable arterial wall with filtration flow would be invaluable for simulation of the flow field and concentration field in sequence. However, this type of highly coupled interaction analysis has not yet been attempted. Therefore, we performed a coupled analysis of an artery with multiple bends in sequence. First, based on the theory of porous media, we modeled a deformable arterial wall using a porohyperelastic model (PHEM) that was able to express both the filtration flow and the viscoelastic behavior of the living tissue, and simulated a blood flow field in the arterial lumen, a filtration flow field and a displacement field in the arterial wall using a fluid-structure interaction (FSI) program code by the finite element method (FEM). Next, based on the obtained results, we further simulated LDL transport using a mass transfer analysis code by the FEM. We analyzed the PHEM in comparison with a rigid model. For the blood flow, stagnation was observed downward of the bends. The direction of the filtration flow was only from the lumen to the wall for the rigid model, while filtration flows from both the wall to the lumen and the lumen to the wall were observed for the PHEM. The LDL concentration was high at the lumenwall interface for both the PHEM and rigid model, and reached its maximum value at the stagnation area. For the PHEM, the maximum LDL concentration in the wall in the radial direction was observed at the position of 3% wall thickness from the lumenwall interface, while for the rigid model, it was observed just at the lumenwall interface. In addition, the peak LDL accumulation area of the PHEM moved about according to the pulsatile flow. These results demonstrate that the blood flow, arterial wall deformation, and filtration flow all affect the LDL concentration, and that LDL accumulation is due to stagnation and the presence of filtration flow. Thus, FSI analysis is indispensable. 相似文献
53.
Otaki JM 《Journal of insect physiology》2007,53(6):526-537
Application of cold shock or tungstate to butterfly pupae produces a unique color-pattern modification type on the adult wings, in which the color-pattern elements are dislocated toward the reduced focal elements. This modification-inducing activity has been primarily attributed to the putative cold-shock hormone (CSH) that is secreted into the hemolymph upon cold shock. Here, using a species of nymphalid butterfly Junonia almana, a new "reversed" type of the color-pattern modifications of butterfly wings was obtained by the application of heat shock or thapsigargin, a calcium-ATPase inhibitor, in which most elements were dislocated away from the enlarged focal elements. This result suggests that the endocrine secretion of CSH is sensitive to a wide range of temperature shocks, which then affects the cellular interpretation of the wing-wide positional information that is emitted from the focal locations. Ecdysteroid contributes to the wing-wide patterning primarily independently from CSH, but these two systems negatively interact with each other, probably in the intracellular signaling pathways. 相似文献
54.
Iida J Wilhelmson KL Ng J Lee P Morrison C Tam E Overall CM McCarthy JB 《The Biochemical journal》2007,403(3):553-563
We previously reported that CS (chondroitin sulfate) GAG (glycosaminoglycan), expressed on MCSP (melanoma-specific CS proteoglycan), is important for regulating MT3-MMP [membrane-type 3 MMP (matrix metalloproteinase)]-mediated human melanoma invasion and gelatinolytic activity in vitro. In the present study, we sought to determine if CS can directly enhance MT3-MMP-mediated activation of pro-MMP-2. Co-immunoprecipitation studies suggest that MCSP forms a complex with MT3-MMP and MMP-2 on melanoma cell surface. When melanoma cells were treated with betaDX (p-nitro-beta-D-xylopyranoside) to inhibit coupling of CS on the core protein, both active form and proform of MMP-2 were no longer co-immunoprecipitated with either MCSP or MT3-MMP, suggesting a model in which CS directly binds to MMP-2 and presents the gelatinase to MT3-MMP to be activated. By using recombinant proteins, we determined that MT3-MMP directly activates pro-MMP-2 and that this activation requires the interaction of the C-terminal domain of pro-MMP-2 with MT3-MMP. Activation of pro-MMP-2 by suboptimal concentrations of MT3-MMP is also significantly enhanced in the presence of excess C4S (chondroitin 4-sulfate), whereas C6S (chondroitin 6-sulfate) or low-molecular-mass hyaluronan was ineffective. Affinity chromatography studies using CS isolated from aggrecan indicate that the catalytic domain of MT3-MMP and the C-terminal domain of MMP-2 directly bind to the GAG. Thus the direct binding of pro-MMP-2 with CS through the C-domain would present the catalytic domain of pro-MMP-2 to MT3-MMP, which facilitates the generation of the active form of MMP-2. These results suggest that C4S, which is expressed on tumour cell surface, can function to bind to pro-MMP-2 and facilitate its activation by MT3-MMP-expressing tumour cells to enhance invasion and metastasis. 相似文献
55.
Mao Yihang Hafeez Abdul Pan Taowen Wu Chaorong Wang Lei Muramoto Joji Shennan Carol Cai Kunzheng Tian Jihui 《Plant and Soil》2022,477(1-2):539-552
Plant and Soil - Anaerobic soil disinfestation (ASD) has been proven to be an effective and environmentally friendly method for controlling soil-borne plant diseases. Mechanisms of ASD-mediated... 相似文献
56.
57.
Carrageenans (CGNs) are extracted from cell walls of certain algae of the Rhodophyta and are gel-forming polysaccharides. There are three kinds of purified carrageenans available—kappa, lambda, and iota CGN. All of them stimulated responding T lymphocytes in both autologous and allogeneic mixed lymphocyte reaction, lambda CGN being the most effective. Silica particles abrogated proliferation of responding cells in autologous and allogeneic mixed lymphocyte reaction by killing human monocytes. However, when 1 mg/ml of CGN was added to silica-added assay system, CGN could induce proliferation of responding T cells even in the absence of monocytes. It was concluded that CGN was a monocyte-independent T-lymphocyte mitogen that was also toxic for human monocytes. 相似文献
58.
Butterfly wing color-patterns are determined in the prospective wing tissues during the late larval and early pupal stages. To study the cellular differentiation process of wings, morphological knowledge on pupal wings is prerequisite. Here we systematically examined morphological patterns of the pupal wing cuticular surface in a wide variety of nymphalid butterflies in relation to adult color-patterns. Several kinds of pupal wing patterns corresponding to particular adult color-pattern elements were widely observed in many species. Especially noteworthy were the pupal "focal" spots corresponding to the adult border ocelli system, which were detected in many species of Nymphalinae, Apaturinae, Argynninae, Satyrinae, and Danainae. Striped patterns on the pupal wing cuticle seen in some species of Limenitinae, Ariadnae, and Marpesiinae directly corresponded to those of the adult wings. In Vanessa cardui, eyespot-like pattern elements were tentatively produced during development in the wing tissue underneath the pupal spots and subsequently erased, suggesting a mechanism for producing novel color-patterns in the course of development and evolution. The pupal focal spots reasonably correlated with the adult eyespots in size in Precis orithya and Ypthima argus. We physically damaged the pupal focal spots and their corresponding cells underneath in these species, which abolished or inhibited the formation of the adult eyespots. Taken together, our results clarified that pupal cuticle patterns were often indicative of the adult color-patterns and apparently reflect molecular activity of organizing centers for the adult color-pattern formation at least in nymphalid butterflies. 相似文献
59.
Saito K Ishizaka N Aizawa T Sata M Iso-o N Noiri E Mori I Ohno M Nagai R 《American journal of physiology. Heart and circulatory physiology》2005,288(4):H1836-H1843
Long-term administration of angiotensin II causes myocardial loss and cardiac fibrosis. We previously found iron deposition in the heart of the angiotensin II-infused rat, which may promote angiotensin II-induced cardiac damage. In the present study, we have investigated whether an iron chelator (deferoxamine) and a free radical scavenger (T-0970) affect the angiotensin II-induced upregulation of transforming growth factor-beta1 (TGF-beta1). Angiotensin II infusion for 7 days caused a robust increase in TGF-beta1 mRNA expression in vascular smooth muscle cells, myofibroblast-like cells, and migrated monocytes/macrophages. T-0970 and deferoxamine suppressed the upregulation of TGF-beta1 mRNA and reduced the extent of cardiac fibrosis in the heart of rats treated with angiotensin II. These agents blocked the angiotensin II-induced upregulation of heme oxygenase-1, a potent oxidative and cellular stress-responsive gene, but they did not significantly affect systolic blood pressure or plasma levels of aldosterone. In addition, T-0970 and deferoxamine suppressed the angiotensin II-induced upregulation of monocyte chemoattractant protein-1 in the heart. These results collectively suggest that iron and the iron-mediated generation of reactive oxygen species may contribute to angiotensin II-induced upregulation of profibrotic and proinflammatory genes, such as TGF-beta1 and monocyte chemoattractant protein-1. 相似文献
60.
Kim JY Park JS Strassheim D Douglas I Diaz del Valle F Asehnoune K Mitra S Kwak SH Yamada S Maruyama I Ishizaka A Abraham E 《American journal of physiology. Lung cellular and molecular physiology》2005,288(5):L958-L965
High mobility group box 1 (HMGB1) is a novel late mediator of inflammatory responses that contributes to endotoxin-induced acute lung injury and sepsis-associated lethality. Although acute lung injury is a frequent complication of severe blood loss, the contribution of HMGB1 to organ system dysfunction in this setting has not been investigated. In this study, HMGB1 was detected in pulmonary endothelial cells and macrophages under baseline conditions. After hemorrhage, in addition to positively staining endothelial cells and macrophages, neutrophils expressing HMGB1 were present in the lungs. HMGB1 expression in the lung was found to be increased within 4 h of hemorrhage and then remained elevated for more than 72 h after blood loss. Neutrophils appeared to contribute to the increase in posthemorrhage pulmonary HMGB1 expression since no change in lung HMGB1 levels was found after hemorrhage in mice made neutropenic with cyclophosphamide. Plasma concentrations of HMGB1 also increased after hemorrhage. Blockade of HMGB1 by administration of anti-HMGB1 antibodies prevented hemorrhage-induced increases in nuclear translocation of NF-kappa B in the lungs and pulmonary levels of proinflammatory cytokines, including keratinocyte-derived chemokine, IL-6, and IL-1 beta. Similarly, both the accumulation of neutrophils in the lung as well as enhanced lung permeability were reduced when anti-HMGB1 antibodies were injected after hemorrhage. These results demonstrate that hemorrhage results in increased HMGB1 expression in the lungs, primarily through neutrophil sources, and that HMGB1 participates in hemorrhage-induced acute lung injury. 相似文献