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991.
Alterations of the arginine metabolome in asthma 总被引:1,自引:0,他引:1
Lara A Khatri SB Wang Z Comhair SA Xu W Dweik RA Bodine M Levison BS Hammel J Bleecker E Busse W Calhoun WJ Castro M Chung KF Curran-Everett D Gaston B Israel E Jarjour N Moore W Peters SP Teague WG Wenzel S Hazen SL Erzurum SC;National Heart Lung Blood Institute's Severe Asthma Research Program 《American journal of respiratory and critical care medicine》2008,178(7):673-681
992.
993.
Soe Hee Ann Cai De Jin Gillian Balbir Singh Kyung Hun Lim Jae-Wook Chung Scot Garg Moo Hyun Kim Wang-Soo Lee Kyoung Im Cho Sang Wook Kim Eun-Seok Shin 《Heart and vessels》2016,31(11):1767-1775
There is limited research on plaque characteristics of ST elevation myocardial infarction (STEMI) patients according to the gender and age. 280 Consecutive STEMI patients who underwent VH-IVUS imaging on culprit before percutaneous coronary intervention (PCI) were enrolled in this study. Women were significantly older than men (69.8 ± 10 vs. 55.9 ± 11.3, p < 0.001). After propensity matching, men had higher plaque burden (79.7 ± 7.8 vs. 73.7 ± 13.0 %, p = 0.010), more fibro-fatty tissue (12.8 ± 9.9 vs. 9.5 ± 6.8 %, p = 0.04) and less dense calcium than women (8.4 ± 5.8 vs. 12.3 ± 8.7 %, p = 0.007). Subgroups dividing by 50, 65, 75 years old, plaque burden was higher in elderly men aged 66–75 years compared to the young men aged less than 50 (75.5 ± 9.2 vs. 68.4 ± 10.1 %, p = 0.012). And middle aged men ranged 51–65 years showed significantly more plaque burden at minimal lumen area site than matched aged women (77.5 ± 8.0 vs. 69.0 ± 17.6 %, p = 0.012). Elderly women aged 66–75 years showed significantly more necrotic core (28.6 ± 7.3 %) and dense calcium (14.9 ± 7.5 %) compared to all the younger or matched subgroups of men. These differences in plaque composition are blunted in the very elderly of men and women aged over 75 years. The findings may explain the gender differences in clinical prognosis in STEMI patients. 相似文献
994.
Park KC Kim JH Choi EJ Min SW Rhee S Baek SH Chung SS Bang O Park D Chiba T Tanaka K Chung CH 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(15):9733-9738
Protein modification by ubiquitin is a dynamic and reversible process that is involved in the regulation of a variety of cellular processes. Here, we show that myogenic differentiation of embryonic muscle cells is antagonistically regulated by two deubiquitinating enzymes, UBP45 and UBP69, that are generated by alternative splicing. Both enzymes cleaved off ubiquitin from polyubiquitinated protein conjugates in vivo as well as from linear ubiquitin-protein fusions in vitro. In cultured myoblasts, the level of UBP69 mRNA markedly but transiently increased before membrane fusion, whereas that of UBP45 mRNA increased as the cells fused to form myotubes. Both myoblast fusion and accumulation of myosin heavy chain were dramatically stimulated by the stable expression of UBP69 but strongly attenuated by that of the catalytically inactive form of the protease, suggesting that the mutant enzyme acts dominant negatively on the function of the wild-type protease. In contrast, stable expression of UBP45 completely blocked both of the myogenic processes but that of inactive enzyme did not, indicating that the catalytic activity of the enzyme is essential for its inhibitory effects. These results indicate that differential expression of UBP45 and UBP69 is involved in the regulation of muscle cell differentiation. 相似文献
995.
Tomita K Caramori G Lim S Ito K Hanazawa T Oates T Chiselita I Jazrawi E Chung KF Barnes PJ Adcock IM 《American journal of respiratory and critical care medicine》2002,166(5):724-731
Alveolar macrophages (AMs) are the predominant defense cells in the airway, and their numbers are increased in smokers and subjects with chronic obstructive pulmonary disease. This increase may result from increased recruitment, increased proliferation, or reduced cell death. Apoptosis regulates inflammatory cell survival, and p21(CIP1/WAF1) is an important inhibitory regulator of cycle progression after oxidative stress. We have investigated whether chronic smoke exposure influences the expression and localization of cell cycle and apoptotic proteins in AM and bronchial epithelial cells in vivo. The increased numbers of AMs seen in smokers were only partially due to enhanced proliferation. p21(CIP1/WAF1) protein expression was increased in AMs and biopsies isolated from smokers and was found predominantly within the cytoplasm. In addition, B cell lymphoma leukemia (Bcl)-x(L), an antiapoptotic regulator, was also highly expressed in macrophages from smokers compared with nonsmokers and subjects with asthma. Hydrogen peroxide, an oxidative stress, induced cytoplasmic expression of p21(CIP1/WAF1) and failed to induce apoptosis in an in vitro model. These results suggested that AM and bronchial epithelial cells from smokers, in contrast to those from normal subjects and subjects with asthma, have reduced cell death. Thus, oxidative stress induced by cigarette smoking may contribute to the chronicity of inflammation in the airway, through a reduction of apoptosis. 相似文献
996.
Cotransplantation of third-party mesenchymal stromal cells can alleviate single-donor predominance and increase engraftment from double cord transplantation 总被引:12,自引:1,他引:12
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Although the infusion of umbilical cord blood (UCB) from multiple donors can be a strategy to overcome the cell dose limitation frequently encountered in UCB transplantation, clinical trials have revealed that cells from one donor dominate engraftment. To investigate the origin of and the factors influencing this inequality, we performed mixed transplantation of 2 UCB units with varying degrees of HLA disparities into NOD/SCID mice and determined donor origins by polymerase chain reaction-sequence-specific oligonucleotide probe (PCR-SSOP) or real-time quantitative (RQ)-PCR for human short tandem repeats (STRs). When total mononuclear cells from 2 units were transplanted as a mixture, cells from one donor predominated (ratio, 81:19), despite comparable overall engraftment when infused as single units, and no augmentation in overall engraftment was observed when compared with the single-unit controls. However, lineage depletion or cotransplantation of mesenchymal stromal cells (MSCs) expanded from third-party bone marrow resulted in more balanced coengraftment. Direct comparison of double UCB transplantation in the presence or absence of MSCs showed that the reduced deviation in the donor ratio (1.8:1 vs. 2.8:1) correlated with a higher overall level of engraftment with MSC cotransplantation. These results indicate that third-party MSCs can be used to alleviate donor deviation and to facilitate engraftment of multidonor UCB. 相似文献
997.
Sung Soo Kim Yeo Min Lee Hyung Keun Kim Jin Il Kim Hiun Suk Chae In Sik Chung Doo Ho Park 《Taehan Sohwagi Hakhoe chi》2007,50(6):363-369
BACKGROUND/AIMS: This study was designed to investigate the role of gastric acid in the extent of H. pylori-induced gastritis. METHODS: Twenty eight mice were inoculated with live H. pylori. They were allocated into four groups. Mice in group I received no treatment, group II mice were treated with sham injection, group III received 125 microg/kg body weight of pentagastrin, while group IV received 250 microg/kg body weight of pentagastrin subcutaneously three times a week. After 7 months, the mucosal pH, H. pylori density, neutrophils and monocytes infiltration, and the degree of atrophy were assessed in the stomach. RESULTS: In the gastric body, the densities of H. pylori were not different among groups. The degree of neutrophil infiltration was significantly lower in group IV compared to other groups (p<0.05). The degree of monocyte infiltration was also significantly lower in group IV than group III (p<0.05). In the gastric antrum, there was no significant difference of the H. pylori density, neutrophil and monocyte infiltration, and degree of atrophy among the groups. The mice with the gastric mucosal pH lower than mean of 3.2 had significant lower level of H. pylori density (1.4 vs. 2.4, p=0.04), and infiltration of neutrophils (0.9 vs. 2.3, p=0.018), and monocytes (1.2 vs. 1.8; p=0.011) than the those with mucosal pH above 3.2 in the body of stomach. CONCLUSIONS: Gastric acid plays a role in suppressing the proximal propagation of H. pylori-induced gastritis to the body of stomach. 相似文献
998.
999.
1000.
Jung Hyun Jo Huapyong Kang Hee Seung Lee Moon Jae Chung Jeong Youp Park Seungmin Bang Seung Woo Park Si Young Song 《Hepatobiliary & pancreatic diseases international : HBPD INT》2019,18(1):62-66