Zhang L.,Peking Union Medical College |
Shen M.,Key Laboratory of Rheumatology and Clinical Immunology |
Zhang F.,Key Laboratory of Rheumatology and Clinical Immunology |
Tang F.,Key Laboratory of Rheumatology and Clinical Immunology
Rheumatology International | Year: 2014
The aim of this study was to analyze the characteristics of patients with diffuse connective tissue diseases (CTDs) complicated by pneumomediastinum and identify the risk factors associated with increased mortality in these patients. Twenty-eight patients with CTD-associated pneumomediastinum, who were admitted to our hospital from January 1997 to June 2012, were prospectively studied. Their demographic characteristics, time to death, and potential risk factors were assessed. Survival curves were depicted by the Kaplan–Meier method. Univariate and multivariate survival analyses were performed by Cox regression. Of the 28 patients, 21 had dermatomyositis; two, polymyositis; three, systemic lupus erythematosus; one, polyarteritis nodosa; and one, undifferentiated CTD. The mean follow-up period was 1,461 days (54–5,264). The cumulative estimated Kaplan–Meier survival rate was 68 % at 1 week, 50 % at 1 month, and 43 % at 1 year. According to univariate analysis, higher serum albumin level (HR 0.87, 95 % CI 0.78–0.98), “slow air leak” (defined as time to progression of dyspnea [newly acquired respiratory failure, mechanical ventilation required, or decrease in PaO2 >30 mmHg after pneumomediastinum]) >3 days (HR 0.07, 95 % CI 0.02–0.34), and early initiation of immunosuppressive agents (within 1 month of steroid therapy; HR 0.27, 95 % CI 0.09–0.81) were associated with better prognosis. Final regression analysis revealed that slow air leak was associated with a lower mortality risk. We found that slow air leak was independently associated with better prognosis. Furthermore, most patients (86 %) who survived for at least 1 month following the pneumomediastinum event subsequently survived beyond 1 year. © 2014, Springer-Verlag Berlin Heidelberg.
Liu C.,Tsinghua University |
Liu C.,Collaborative Innovation Center for Infectious Diseases |
Zhao X.W.,Tsinghua University |
Xu L.L.,Tsinghua University |
And 9 more authors.
Journal of Leukocyte Biology | Year: 2015
Advanced live cell imaging studies suggested that B cell activation is initiated by the formation of BCR microclusters and subsequent B cell IS upon BCR and antigen recognition. PKC family member PKCβ is highly expressed in B cells and plays an important role in the initiation of B cell activation. Here, we reported an inhibitory function of PKCβ through a negative-feedback manner in B cell activation. Compared with WT (PKCβ- WT) or the constitutively active (PKCβ-ΔNPS) form of PKCβ, DN PKCβ (PKCβ-DN) unexpectedly enhanced the accumulation of BCR microclusters into the B cell IS, leading to the recruitment of an excessive amount of pSyk, pPLC-γ2, and pBLNK signaling molecules into the membrane-proximal BCR signalosome. Enhanced calcium mobilization responses in the decay phase were also observed in B cells expressing PKCβ-DN. Mechanistic studies showed that this negative-feedback function of PKCβ works through the induction of an inhibitory form of pBtk at S180 (pBtk-S180). Indeed, the capability of inducing the formation of an inhibitory pBtk-S180 is in the order of PKCβ-ΔNPS. PKCβ-WT. PKCβ-DN. Thus, these results improve our comprehensive understanding on the positive and negative function of PKCβ in the fine tune of B cell activation. © Society for Leukocyte Biology.
Xu L.,Tsinghua University |
Xu L.,Collaborative Innovation Center for Infectious Diseases |
Xu L.,Peking Union Medical College |
Xu L.,Key Laboratory of Rheumatology and Clinical Immunology |
And 12 more authors.
Journal of Leukocyte Biology | Year: 2015
Sphingolipid- and cholesterol-rich lipid raft microdomains are important in the initiation of BCR signaling. Although it is known that lipid rafts promote the coclustering of BCR and Lyn kinase microclusters within the B cell IS, the molecular mechanism of the recruitment of lipid rafts into the B cell IS is not understood completely. Here, we report that the synaptic recruitment of lipid rafts is dependent on the cytoskeleton-remodeling proteins, RhoA and Vav. Such an event is also efficiently regulated by motor proteins, myosin IIA and dynein. Further evidence suggests the synaptic recruitment of lipid rafts is, by principle, an event triggered by BCR signaling molecules and second messenger molecules. BCR-activating coreceptor CD19 potently enhances such an event depending on its cytoplasmic Tyr421 and Tyr482 residues. The enhancing function of the CD19-PI3K module in synaptic recruitment of lipid rafts is also confirmed in human peripheral blood B cells. Thus, these results improve our understanding of the molecular mechanism of the recruitment of lipid raft microdomains in B cell IS. © Society for Leukocyte Biology.
Chen Z.,Peking Union Medical College |
Chen Z.,Key Laboratory of Rheumatology and Clinical Immunology |
Li M.-T.,Peking Union Medical College |
Li M.-T.,Key Laboratory of Rheumatology and Clinical Immunology |
And 11 more authors.
PLoS ONE | Year: 2014
Objective: Protein-losing enteropathy (PLE) is a complication in some systemic lupus erythematosus (SLE) patients that is often misdiagnosed. With this study, we provide insight into clinical characteristics, laboratory characteristics, diagnostic tests, risk factors, treatment, and prognosis of the disease. Methods: A retrospective, case-control study was performed in 44 patients with SLE-related PLE (PLE group) and 88 patients with active SLE (control group) admitted to our care from January 20002January 2012. Risk factors for SLErelated PLE were examined, and we analyzed the accuracy of single and combined laboratory characteristics in discriminating SLE-related PLE from active SLE. Serum albumin and C3 levels were measured as outcome during and after treatment with corticosteroids and immunosuppressive agents. Results: The PLE group had lower mean serum albumin and 24-hour urine protein levels, higher mean total plasma cholesterol levels, and greater frequencies of anti SSA and SSB seropositivity compared with the control group. Anti-SSA seropositivity, hypoalbuminemia, and hypercholesterolemia were independent risk factors for SLE-related PLE. The simultaneous presence of serum albumin (<22 g/ l) and 24-hour urine protein (<0.8 g/24 h) had high specificity, positive predictive value, negative predictive value, and positive likelihood ratio, a low negative likelihood ratio and no significant reduction in sensitivity. High dosage of glucocorticosteroid combined with cyclophosphomide were mostly prescribed for SLE-related PLE. Conclusion: SLE-related PLE should be considered when an SLE patient presents with generalized edema, anti-SSA antibody seropositivity, hypercholesterolemia, severe hypoalbuminemia, and low 24-hour urine protein levels. Aggressive treatment for lupus might improve prognosis. © 2014 Chen et al.
Xianbin W.,Peking Union Medical College |
Xianbin W.,Key Laboratory of Rheumatology and Clinical Immunology |
Mingyu W.,Peking Union Medical College |
Mingyu W.,Key Laboratory of Rheumatology and Clinical Immunology |
And 8 more authors.
Medicine (United States) | Year: 2015
This article aims to analyze the frequency and clinical characteristics of peripheral neuropathy (PN) in patients with systemic lupus erythematosus (SLE). A total of 4924 SLE patients admitted to the Peking Union Medical College Hospital, Beijing, China, from January 1995 to September 2013 were included in this retrospective analysis. The individuals designated as control patients were selected from the pool of SLE patients without PN using the systematic sampling method of 1:2 during the same time. The prevalence of SLE-associated PN (SLE-PN) in SLE patients was 1.5% (73/4924). Seventy-nine cases of PN affected 73 patients and 6 of these patients (8.2%) presented with 2 types of PN. Among the 7 types of PN, polyneuropathy was the most frequent and was diagnosed in 47 cases (59.5%); the remaining patients suffered from mononeuropathy (13.9%), cranial neuropathy (12.7%), myasthenia gravis (10.1%), autonomic neuropathy (2.5%), or acute inflammatory demyelinating polyradiculoneuropathy (1.3%). Five patients developed PN before the onset of SLE (3 out of 5 patients had myasthenia gravis). The most common PN-related symptoms were myasthenia and numbness (50.6%), followed by pain in affected regions (35.9%). PN symptoms were relieved in a majority of the patients (76.7%) after treatment. Compared with non-SLE-PN patients, patients with SLE-PN had a higher frequency of fever (65.8% vs 45.9%, P<0.01), mucocutaneous involvement (73.9% vs 36.3%, P<0.01), arthritis (42.5% vs 28.1%, P<0.05), myositis (17.8% vs 5.5%, P<0.01), and central nervous system involvement (38.4% vs 21.9%, P<0.05) as well as being positive for the anti-Sm antibody (31.4% vs 18.8%), immunoglobulin G (IgG) elevation (53.6% vs 37.1%, P<0.01), and reduction in complement 3 (54.8% vs 36.9%, P<0.05). A statistically significant difference was found between the Systemic Lupus Erythematosus Disease Activity Index scores in SLE-PN patients compared with the non-SLE-PN patients (P<0.05). Multivariate logistic regression showed that the only risk factor for PN was IgG elevation (odds ratio=2.553, 1.224-5.327, P=0.012). The prevalence of PN in SLE occurs more frequently in patients with an active form of the disease. IgG elevation is a risk factor for SLE-PN and should be assessed in these patients. Young female patients with myasthenia gravis should be closely monitored for the development of SLE. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.