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61.
Larsen KO Yndestad A Sjaastad I Løberg EM Goverud IL Halvorsen B Jia J Andreassen AK Husberg C Jonasson S Lipp M Christensen G Aukrust P Skjønsberg OH 《American journal of physiology. Lung cellular and molecular physiology》2011,301(1):L50-L59
The chemokine receptor CCR7 regulates lymphocyte trafficking, and CCR7 deficiency induces infiltration of T and B cells adjacent to vessels in mouse lungs. Perivascular infiltration of T and B cells has also been found in human pulmonary arterial hypertension, and downregulation of the CCR7 receptor in circulating leukocytes of such patients has been observed. To investigate whether changes in the CCR7 system contribute to the pathogenesis of pulmonary hypertension, we utilized mice deficient of the CCR7 receptor. The cardiopulmonary and inflammatory responses of CCR7 depletion were evaluated in CCR7-deficient and wild-type mice. Measurements of cytokines upregulated in the animal model were also performed in patients with pulmonary hypertension and controls and in vascular smooth muscle cells. We found that mice lacking CCR7 had increased right ventricular systolic pressure, reduced pulmonary artery acceleration time, increased right ventricular/tibial length ratio, Rho kinase-mediated pulmonary vasoconstriction, and increased muscularization of distal arteries, indicating pulmonary hypertension. These mice also showed increased perivascular infiltration of leukocytes, consisting mainly of T and B cells, and increased mRNA levels of the inflammatory cytokines interleukin-12 and CX3CL1 within pulmonary tissue. Increased serum levels of interleukin-12 and CX3CL1 were also observed in patients with pulmonary hypertension, particularly in those with pulmonary hypertension associated with connective tissue disorder. In smooth muscle cells, interleukin-12 induced secretion of the angiogenic cytokine interleukin-8. We conclude that these results suggest a role for CCR7 in the development of pulmonary arterial hypertension, at least in some subgroups, possibly via pulmonary infiltration of lymphocytes and secretion of interleukin-12 and CX3CL1. 相似文献
62.
Innala L Möller B Ljung L Magnusson S Smedby T Södergren A Öhman ML Rantapää-Dahlqvist S Wållberg-Jonsson S 《Arthritis research & therapy》2011,13(4):R131
Introduction
Co-morbidity and mortality due to cardiovascular disease (CVD) are increased in patients with rheumatoid arthritis (RA). Most published studies in this field are retrospective or cross sectional. We investigated the presence of traditional and disease related risk factors for CVD at the onset of RA and during the first five years following diagnosis. We also evaluated their potential for predicting a new cardiovascular event (CVE) during the five-year follow-up period and the modulatory effect of pharmacological treatment. 相似文献63.
The use of transgenic livestock is providing new methods for obtaining pharmaceutically useful proteins. However, the protein expression profiles of the transgenic animals, including expression of milk fat globule membrane (MFGM) proteins, have not been well characterized. In this study, we compared the MFGM protein expression profile of the colostrum and mature milk from three lines of transgenic cloned (TC) cattle, i.e., expressing recombinant human α-lactalbumin (TC-LA), lactoferrin (TC-LF) or lysozyme (TC-LZ) in the mammary gland, with those from cloned non-transgenic (C) and conventionally bred normal animals (N). We identified 1, 225 proteins in milk MFGM, 166 of which were specifically expressed only in the TC-LA group, 265 only in the TC-LF group, and 184 only in the TC-LZ group. There were 43 proteins expressed only in the transgenic cloned animals, but the concentrations of these proteins were below the detection limit of silver staining. Functional analysis also showed that the 43 proteins had no obvious influence on the bovine mammary gland. Quantitative comparison revealed that MFGM proteins were up- or down-regulated more than twofold in the TC and C groups compared to N group: 126 in colostrum and 77 in mature milk of the TC-LA group; 157 in colostrum and 222 in mature milk of the TC-LF group; 49 in colostrum and 98 in mature milk of the TC-LZ group; 98 in colostrum and 132 in mature milk in the C group. These up- and down-regulated proteins in the transgenic animals were not associated with a particular biological function or pathway, which appears that expression of certain exogenous proteins has no general deleterious effects on the cattle mammary gland. 相似文献
64.
Tao Tan Jun Wu Chenyang Si Shaoxing Dai Youyue Zhang Nianqin Sun E Zhang Honglian Shao Wei Si Pengpeng Yang Hong Wang Zhenzhen Chen Ran Zhu Yu Kang Reyna Hernandez-Benitez Llanos Martinez Martinez Estrella Nuñez Delicado W. Travis Berggren Juan Carlos Izpisua Belmonte 《Cell》2021,184(8):2020-2032.e14
65.
Traxlmayr MW Wozniak-Knopp G Antes B Stadlmayr G Rüker F Obinger C 《Journal of biotechnology》2011,155(2):193-202
Recently, it has been demonstrated that loops of the crystallizable fragment of IgG1 (IgG1-Fc) can be engineered to form antigen-binding sites. In this work C-terminal structural loops in the CH3 domains of homodimeric IgG1-Fc have been functionalized to form integrin-binding sites in order to probe the effect of engineering on structural integrity and thermal stability of IgG1-Fc as well as on binding to the ligands Protein A, CD16 and FcRn, respectively. The peptide sequence GCRGDCL - a disulfide-bridged cyclic heptapeptide that confers binding to human αvβ3 integrin was introduced into AB, CD and/or EF loops and single and double mutants were heterologously expressed in Pichia pastoris. Integrin binding of engineered IgG-Fc was tested using both binding to coated αvβ3 integrin in ELISA or to αvβ3-expressing K562 cells in FACS analysis. Additionally, blocking of αvβ3-mediated cell adhesion to vitronectin was investigated. The data presented in this report demonstrate that bioactive integrin-binding peptide(s) can be grafted on the C-terminal loops of IgG-Fc without impairing binding to effector molecules. Observed differences between the investigated variants in structural stability and integrin binding are discussed with respect to the known structure of IgG-Fc and its structural loops. 相似文献
66.
Phosphorus effects on metabolic processes in monoxenic arbuscular mycorrhiza cultures 总被引:5,自引:0,他引:5
The influence of external phosphorus (P) on carbon (C) allocation and metabolism as well as processes related to P metabolism was studied in monoxenic arbuscular mycorrhiza cultures of carrot (Daucus carota). Fungal hyphae of Glomus intraradices proliferated from the solid minimal medium containing the colonized roots into C-free liquid minimal medium with different P treatments. The fungus formed around three times higher biomass in P-free liquid medium than in medium with 2.5 mM inorganic P (high-P). Mycelium in the second experiment was harvested at an earlier growth stage to study metabolic processes when the mycelium was actively growing. P treatment influenced the root P content and [(13)C]glucose administered to the roots 7 d before harvest gave a negative correlation between root P content and (13)C enrichment in arbuscular mycorrhiza fungal storage lipids in the extraradical hyphae. Eighteen percent of the enriched (13)C in extraradical hyphae was recovered in the fatty acid 16:1omega5 from neutral lipids. Polyphosphate accumulated in hyphae even in P-free medium. No influence of P treatment on fungal acid phosphatase activity was observed, whereas the proportion of alkaline-phosphatase-active hyphae was highest in high-P medium. We demonstrated the presence of a motile tubular vacuolar system in G. intraradices. This system was rarely seen in hyphae subjected to the highest P treatment. We concluded that the direct responses of the extraradical hyphae to the P concentration in the medium are limited. The effects found in hyphae seemed instead to be related to increased availability of P to the host root. 相似文献
67.
68.
Briva A Vadász I Lecuona E Welch LC Chen J Dada LA Trejo HE Dumasius V Azzam ZS Myrianthefs PM Batlle D Gruenbaum Y Sznajder JI 《PloS one》2007,2(11):e1238
Background
In patients with acute respiratory failure, gas exchange is impaired due to the accumulation of fluid in the lung airspaces. This life-threatening syndrome is treated with mechanical ventilation, which is adjusted to maintain gas exchange, but can be associated with the accumulation of carbon dioxide in the lung. Carbon dioxide (CO2) is a by-product of cellular energy utilization and its elimination is affected via alveolar epithelial cells. Signaling pathways sensitive to changes in CO2 levels were described in plants and neuronal mammalian cells. However, it has not been fully elucidated whether non-neuronal cells sense and respond to CO2. The Na,K-ATPase consumes ∼40% of the cellular metabolism to maintain cell homeostasis. Our study examines the effects of increased pCO2 on the epithelial Na,K-ATPase a major contributor to alveolar fluid reabsorption which is a marker of alveolar epithelial function.Principal Findings
We found that short-term increases in pCO2 impaired alveolar fluid reabsorption in rats. Also, we provide evidence that non-excitable, alveolar epithelial cells sense and respond to high levels of CO2, independently of extracellular and intracellular pH, by inhibiting Na,K-ATPase function, via activation of PKCζ which phosphorylates the Na,K-ATPase, causing it to endocytose from the plasma membrane into intracellular pools.Conclusions
Our data suggest that alveolar epithelial cells, through which CO2 is eliminated in mammals, are highly sensitive to hypercapnia. Elevated CO2 levels impair alveolar epithelial function, independently of pH, which is relevant in patients with lung diseases and altered alveolar gas exchange. 相似文献69.
70.
Hye Ran Park Jae Meen Lee Gwanhee Ehm Hui-Jun Yang In Ho Song Yong Hoon Lim Mi-Ryoung Kim Keyoung Ran Kim Woong-Woo Lee Young Eun Kim Jae Ha Hwang Chae Won Shin Hyeyoung Park Jin Wook Kim Han-Joon Kim Cheolyoung Kim Dong Gyu Kim Beom Seok Jeon Sun Ha Paek 《PloS one》2016,11(1)