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ID PMID Title PublicationDate abstract
24423912 [Early efficacies of total knee arthroplasty for knees with severe lateral instability]. 2013 Nov 19 OBJECTIVE: To evaluate the outcomes of primary total knee arthroplasty (TKA) in the treatment of knee with severe lateral instability and summarize the essential points of operation and rehabilitation. METHODS: From February 2005 to August 2010, primary TKA was performed in 27 severe lateral unstable knees (25 cases), including 3 males (3 knees) and 22 females (24 knees). Their mean age was 57.8 (37-71) years. And their primary diseases included rheumatoid arthritis (22 knees in 21 cases) and osteoarthritis (5 knees in 4 cases). Thirteen lateral unstable knees were accompanied with 18.08° ± 5.96°(15-35°) varus deformity; in the rest 14 knees, there was medial instability with 20.71° ± 7.03° (15-35°) valgus deformity. Blood loss volume, operative duration and complications were recorded. During the follow-up period, HSS score, knee stability and varus/valgus status were recorded preoperatively, 1, 3, 6, 12 months and then annually postoperatively. RESULTS: AORI type I bone defect was found at the proximal tibia in 18 knees and distal lateral femoral condyle in 10 knees. All defects were reconstructed with cement or autograft. AORI type II bone defects at proximal tibia in 3 knees were reconstructed with metal augmentation. Blood loss during the first 24 hours were (438.9 ± 109.5) (400-700) ml and operative duration (91.1 ± 11.6) (70-110) min. The mean follow-up period was (41.6 ± 10.9) (27-60) months. At the final follow-up, the HSS score increased from (45.8 ± 5.4) to (85.4 ± 4.5) (t = 30.15, P < 0.01) .Five knees in 5 cases had mild postoperative instability. All cases were allowed to walk with knee orthosis for 4-6 weeks. At the end of follow-up, mild lateral instability of 2 knees persisted. One augmented knee had osteolysis beneath metal block. CONCLUSION: TKA for knees with severe lateral instability requires a deep understanding of causes and a rational treatment. Proper handling of bone defects and careful release of lateral soft tissue are two critical points for postoperative knee stability. Wearing knee orthosis during the early postoperative stage may be helpful or residual mild instability.
24222270 Formulation and optimization of nonionic surfactants emulsified nimesulide-loaded PLGA-bas 2014 Feb This investigation aimed to develop nimesulide (NMS)-loaded poly(lactic-co-glycolic acid) (PLGA)-based nanoparticulate formulations as a biodegradable polymeric drug carrier to treat rheumatoid arthritis. Polymeric nanoparticles (NPs) were prepared with two different nonionic surfactants, vitamin E d-α-tocopheryl polyethylene glycol 1000 succinate (vitamin E TPGS) and poly(vinyl alcohol) (PVA), using an ultrasonication solvent evaporation technique. Nine batches were formulated for each surfactant using a 3(2) factorial design for optimal concentration of the emulsifying agents, 0.03-0.09% for vitamin E TPGS and 2-4% for PVA. The surfactant percentage and the drug/polymer ratio (1:10, 1:15, 1:20) of the NMS-loaded NPs were investigated based on four responses: encapsulation efficiency, particle size, the polydispersity index, and the surface charge. The response surface plots and linearity curves indicated a relationship between the experiment's responses and a set of independent variables. The NPs produced with both surfactants exhibited a negative surface charge, and scanning electron micrographs revealed that all of the NPs were spherical in shape. A narrower size distribution and higher drug loadings were achieved in PVA-emulsified PLGA NPs than in the vitamin E TPGS emulsified. Decreasing amounts of both nonionic surfactants resulted in a reduction in the emulsion's viscosity, which led to a decrease in the particle size of NPs. According to the ANOVA results obtained in this present research, vitamin E TPGS exhibited the best correlation between the independent variables, namely drug/polymer ratio and the surfactant percentage, and the dependent variables (encapsulation efficiency R(2) = 0.9603, particle size R(2) = 0.9965, size distribution R(2) = 0.9899, and surface charge R(2) = 0.8969) compared with PVA.
24167573 Powerful haplotype-based Hardy-Weinberg equilibrium tests for tightly linked loci. 2013 Recently, there have been many case-control studies proposed to test for association between haplotypes and disease, which require the Hardy-Weinberg equilibrium (HWE) assumption of haplotype frequencies. As such, haplotype inference of unphased genotypes and development of haplotype-based HWE tests are crucial prior to fine mapping. The goodness-of-fit test is a frequently-used method to test for HWE for multiple tightly-linked loci. However, its degrees of freedom dramatically increase with the increase of the number of loci, which may lack the test power. Therefore, in this paper, to improve the test power for haplotype-based HWE, we first write out two likelihood functions of the observed data based on the Niu's model (NM) and inbreeding model (IM), respectively, which can cause the departure from HWE. Then, we use two expectation-maximization algorithms and one expectation-conditional-maximization algorithm to estimate the model parameters under the HWE, IM and NM models, respectively. Finally, we propose the likelihood ratio tests LRT[Formula: see text] and LRT[Formula: see text] for haplotype-based HWE under the NM and IM models, respectively. We simulate the HWE, Niu's, inbreeding and population stratification models to assess the validity and compare the performance of these two LRT tests. The simulation results show that both of the tests control the type I error rates well in testing for haplotype-based HWE. If the NM model is true, then LRT[Formula: see text] is more powerful. While, if the true model is the IM model, then LRT[Formula: see text] has better performance in power. Under the population stratification model, LRT[Formula: see text] is still more powerful. To this end, LRT[Formula: see text] is generally recommended. Application of the proposed methods to a rheumatoid arthritis data set further illustrates their utility for real data analysis.
25550360 Antioxidant vitamin intake and mortality: the Leisure World Cohort Study. 2015 Jan 15 To assess the relationship between antioxidant vitamin intake and all-cause mortality in older adults, we examined these associations using data from the Leisure World Cohort Study, a prospective study of residents of the Leisure World retirement community in Laguna Hills, California. In the early 1980s, participants (who were aged 44-101 years) completed a postal survey, which included details on use of vitamin supplements and dietary intake of foods containing vitamins A and C. Age-adjusted and multivariate-adjusted (for factors related to mortality in this cohort—smoking, alcohol intake, caffeine consumption, exercise, body mass index, and histories of hypertension, angina, heart attack, stroke, diabetes, rheumatoid arthritis, and cancer) hazard ratios for death were calculated using Cox regression for 8,640 women and 4,983 men (median age at entry, 74 years). During follow-up (1981-2013), 13,104 participants died (median age at death, 88 years). Neither dietary nor supplemental intake of vitamin A or vitamin C nor supplemental intake of vitamin E was significantly associated with mortality after multivariate adjustment. A compendium that summarizes previous findings of cohort studies evaluating vitamin intake and mortality is provided. Attenuation in the observed associations between mortality and antioxidant vitamin use after adjustment for confounders in our study and in previous studies suggests that such consumption identifies persons with other mortality-associated lifestyle and health risk factors.
25392121 Fc gamma receptor-TLR cross-talk elicits pro-inflammatory cytokine production by human M2 2014 Nov 13 M2 macrophages suppress inflammation in numerous disorders, including tumour formation, infection and obesity. However, the exact role of M2 macrophages in the context of several other diseases is still largely undefined. We here show that human M2 macrophages promote inflammation instead of suppressing inflammation on simultaneous exposure to complexed IgG (c-IgG) and TLR ligands, as occurs in the context of diseases such as rheumatoid arthritis (RA). c-IgG-TLR ligand co-stimulation of M2 macrophages selectively amplifies production of pro-inflammatory cytokines TNF-α, IL-1β and IL-6 and promotes Th17 responses, which all play a critical role in RA pathology. Induction of pro-inflammatory cytokines on c-IgG co-stimulation mainly depends on Fc gamma receptor IIa (FcγRIIa), which selectively amplifies cytokine gene transcription and induces caspase-1 activation. These data indicate that FcγR-TLR cross-talk may be targeted for treatment to attenuate inflammation in RA, by restoring the anti-inflammatory function of M2 macrophages.
24735118 G protein-coupled receptor kinase 2 moderates recruitment of THP-1 cells to the endotheliu 2014 Feb BACKGROUND: G protein-coupled receptors (GPCRs) are a major family of signaling molecules, central to the regulation of inflammatory responses. Their activation upon agonist binding is attenuated by GPCR kinases (GRKs), which desensitize the receptors through phosphorylation. G protein-coupled receptor kinase 2(GRK2) down-regulation in leukocytes has been closely linked to the progression of chronic inflammatory disorders such as rheumatoid arthritis and multiple sclerosis. Because leukocytes must interact with the endothelium to infiltrate inflamed tissues, we hypothesized that GRK2 down-regulation in endothelial cells would also be pro-inflammatory. OBJECTIVES: To determine whether GRK2 down-regulation in endothelial cells is pro-inflammatory. METHODS: siRNA-mediated ablation of GRK2 in human umbilical vein endothelial cells (HUVECs) was used in analyses of the role of this kinase. Microscopic and biochemical analyses of Weibel-Palade body (WPB) formation and functioning, live cell imaging of calcium concentrations and video analyses of adhesion of monocyte-like THP-1 cells provide clear evidence of GRK2 function in histamine activation of endothelial cells. RESULTS: G protein-coupled receptor kinase 2 depletion in HUVECs increases WPB exocytosis and P-selectin-dependent adhesion of THP-1 cells to the endothelial surface upon histamine stimulation, relative to controls. Further, live imaging of intracellular calcium concentrations reveals amplified histamine receptor signaling in GRK2-depleted cells, suggesting GRK2 moderates WPB exocytosis through receptor desensitization. CONCLUSIONS: G protein-coupled receptor kinase 2 deficiency in endothelial cells results in increased pro-inflammatory signaling and enhanced leukocyte recruitment to activated endothelial cells. The ability of GRK2 to modulate initiation of inflammatory responses in endothelial cells as well as leukocytes now places GRK2 at the apex of control of this finely balanced process.
23997215 Macrophage-derived IL-33 is a critical factor for placental growth. 2013 Oct 1 IL-33, the most recently discovered member of the IL-1 superfamily and ligand for the transmembrane form of ST2 (ST2L), has been linked to several human pathologies including rheumatoid arthritis, asthma, and cardiovascular disease. Deregulated levels of soluble ST2, the natural IL-33 inhibitor, have been reported in sera of preeclamptic patients. However, the role of IL-33 during healthy pregnancy remains elusive. In the current study, IL-33 was detected in the culture supernatants of human placental and decidual macrophages, identifying them as a major source of secreted IL-33 in the uteroplacental unit. Because flow cytometry and immunofluorescence stainings revealed membranous ST2L expression on specific trophoblast populations, we hypothesized that IL-33 stimulates trophoblasts in a paracrine manner. Indeed, BrdU incorporation assays revealed that recombinant human IL-33 significantly increased proliferation of primary trophoblasts as well as of villous cytotrophoblasts and cell column trophoblasts in placental explant cultures. These effects were fully abolished upon addition of soluble ST2. Interestingly, Western blot and immunofluorescence analyses demonstrated that IL-33 activates AKT and ERK1/2 in primary trophoblasts and placental explants. Inhibitors against PI3K (LY294002) and MEK1/2 (UO126) efficiently blocked IL-33-induced proliferation in all model systems used. In summary, with IL-33, we define for the first time, to our knowledge, a macrophage-derived regulator of placental growth during early pregnancy.
23981537 Metabolic features of the cell danger response. 2014 May The cell danger response (CDR) is the evolutionarily conserved metabolic response that protects cells and hosts from harm. It is triggered by encounters with chemical, physical, or biological threats that exceed the cellular capacity for homeostasis. The resulting metabolic mismatch between available resources and functional capacity produces a cascade of changes in cellular electron flow, oxygen consumption, redox, membrane fluidity, lipid dynamics, bioenergetics, carbon and sulfur resource allocation, protein folding and aggregation, vitamin availability, metal homeostasis, indole, pterin, 1-carbon and polyamine metabolism, and polymer formation. The first wave of danger signals consists of the release of metabolic intermediates like ATP and ADP, Krebs cycle intermediates, oxygen, and reactive oxygen species (ROS), and is sustained by purinergic signaling. After the danger has been eliminated or neutralized, a choreographed sequence of anti-inflammatory and regenerative pathways is activated to reverse the CDR and to heal. When the CDR persists abnormally, whole body metabolism and the gut microbiome are disturbed, the collective performance of multiple organ systems is impaired, behavior is changed, and chronic disease results. Metabolic memory of past stress encounters is stored in the form of altered mitochondrial and cellular macromolecule content, resulting in an increase in functional reserve capacity through a process known as mitocellular hormesis. The systemic form of the CDR, and its magnified form, the purinergic life-threat response (PLTR), are under direct control by ancient pathways in the brain that are ultimately coordinated by centers in the brainstem. Chemosensory integration of whole body metabolism occurs in the brainstem and is a prerequisite for normal brain, motor, vestibular, sensory, social, and speech development. An understanding of the CDR permits us to reframe old concepts of pathogenesis for a broad array of chronic, developmental, autoimmune, and degenerative disorders. These disorders include autism spectrum disorders (ASD), attention deficit hyperactivity disorder (ADHD), asthma, atopy, gluten and many other food and chemical sensitivity syndromes, emphysema, Tourette's syndrome, bipolar disorder, schizophrenia, post-traumatic stress disorder (PTSD), chronic traumatic encephalopathy (CTE), traumatic brain injury (TBI), epilepsy, suicidal ideation, organ transplant biology, diabetes, kidney, liver, and heart disease, cancer, Alzheimer and Parkinson disease, and autoimmune disorders like lupus, rheumatoid arthritis, multiple sclerosis, and primary sclerosing cholangitis.
23970345 Progesterone protects ovarian cancer cells from cisplatin-induced inhibitory effects throu 2013 Nov Progesterone, also known as P4 (pregn-4-ene-3, 20-dione), is a C-21 steroid hormone involved in the female menstrual cycle, pregnancy (supports gestation) and embryogenesis of humans and other species. Despite the physiological effects, P4 is also effective for the treatment of numerous pathological states, such as multiple sclerosis, rheumatoid arthritis and systemic lupus erythematosus as well as cancer. Considering the hormone microenvironment of gynecological cancers, P4 should be particularly noted in ovarian cancer. The present study demonstrated that P4 protected the ovarian cancer cell line HO-8910 from cisplatin (CDDP)-induced cell cycle arrest and restored the cell migratory capability following treatment of CDDP. Mechanistically, both progesterone receptor membrane component 1 (PGRMC1) and the progesterone receptor (PGR) were decreased in the cells treated with CDDP plus P4, while the level of progesterone receptor membrane component 2 (PGRMC2) was significantly elevated. Reversely, in the HO-8910 cells treated with CDDP alone, levels of both PGRMC1 and PGR were increased while the level of PGRMC2 was decreased. In addition to the receptor expression profile, the PI3K/AKT signaling pathway was also involved in the action of P4 in the CDDP-resistant HO-8910 cells, and a chemical inhibitor for PI3K, LY294002, significantly abolished the anti-apoptotic effect of P4. Consequently, the addition of a PI3K inhibitor to CDDP-based chemotherapy may have a more beneficial application for ovarian cancer therapy.
23775455 Endothelial nitric oxide synthase gene polymorphisms and the risk of osteonecrosis of the 2013 Nov PURPOSE: Nitric oxide (NO), a short-lived gaseous free radical, is a potent mediator of biological responses involved in the pathogenesis of autoimmune rheumatic diseases, such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Nitric oxide also serves as an important signal in physiological processes, including angiogenesis, thrombosis, and bone turnover, which are known to be related to the pathogenesis of osteonecrosis. We investigated whether NOS3 gene polymorphisms are associated with risk of osteonecrosis of the femoral head (ONFH). METHODS: Five polymorphisms in the NOS3 gene were genotyped using TaqMan assays in 306 controls, 150 SLE patients, and 50 SLE patients with ONFH (SLE_ONFH). RESULTS: We found that Asp258Asp and Glu298Asp (G894T) polymorphisms in the NOS3 gene were significantly associated with risk of ONFH. Additionally, we calculated haplotype frequencies of a linkage disequilibrium (LD) block in NOS3 (rs1799983 - rs1800780) and tested for haplotype associations. The haplotypes G-A and T-A showed significant protective (P = 1.6 × 10(-3); OR 0.39, 95 % confidence intervals (CI) 0.22-0.7) and increased risk (P = 2.0 x 10(-5)-6.0 x 10(-4); OR 3.17-3.73) effects for ONFH, respectively. CONCLUSIONS: These results suggest that exonic NOS3 polymorphisms may increase the risk of ONFH in Korean SLE patients.
23619715 The cytotoxic effects of certolizumab pegol and golimumab mediated by transmembrane tumor 2013 May BACKGROUND: Anti-tumor necrosis factor α (anti-TNF-α) agents have been successfully applied for the treatment of rheumatoid arthritis, Crohn's disease, and other chronic inflammatory diseases. Not only the neutralization of soluble TNF-α but also the effect on transmembrane TNF-α is important mechanisms of action of anti-TNF-α agents. This study investigated the cytotoxic effects of new anti-TNF-α agents, certolizumab pegol and golimumab, which are mediated by transmembrane TNF-α. METHODS: Transmembrane TNF-α-expressing Jurkat T cells that did not express TNF receptors were used. The binding ability of each anti-TNF-α agent to transmembrane TNF-α, antibody-dependent cell-mediated cytotoxicity, complement-dependent cytotoxicity, and the apoptotic effect were examined. RESULTS: Certolizumab pegol and golimumab bound to transmembrane TNF-α. Golimumab induced antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity, which was comparable to infliximab and adalimumab. However, certolizumab pegol did not induce antibody-dependent cell-mediated cytotoxicity or complement-dependent cytotoxicity. Certolizumab pegol directly induced nonapoptotic cell death in transmembrane TNF-α-expressing cells. Golimumab induced a weaker apoptotic effect than infliximab and adalimumab. CONCLUSIONS: The cytotoxic effects of anti-TNF-α agents on TNF-α-expressing cells are considered to be associated with the clinical effect of these agents on granulomatous diseases. The direct cytotoxic effect of certolizumab pegol on TNF-α-producing cells may contribute to its clinical efficacy in Crohn's disease. Golimumab may be less effective for granulomatous diseases.
23557090 Associations between selected immune-mediated diseases and tuberculosis: record-linkage st 2013 Apr 4 BACKGROUND: Previous studies have suggested that there may be an association between some immune-mediated diseases and risk of tuberculosis (TB). METHODS: We analyzed a database of linked statistical records of hospital admissions and death certificates for the whole of England (1999 to 2011), and a similar database (the Oxford Record Linkage Study (ORLS)) for a region of southern England in an earlier period. Rate ratios for TB were determined, comparing immune-mediated disease cohorts with comparison cohorts. RESULTS: In the all-England dataset, there were significantly elevated risks of TB after hospital admission for the following individual immune-mediated diseases: Addison's disease, ankylosing spondylitis, autoimmune hemolytic anemia, chronic active hepatitis, coeliac disease, Crohn's disease, dermatomyositis, Goodpasture's syndrome, Hashimoto's thyroiditis, idiopathic thrombocytopenia purpura (ITP), myasthenia gravis, myxedema, pemphigoid, pernicious anemia, polyarteritis nodosa, polymyositis, primary biliary cirrhosis, psoriasis, rheumatoid arthritis, scleroderma, Sjögren's syndrome, systemic lupus erythematosus (SLE), thyrotoxicosis and ulcerative colitis. Particularly high levels of risk were found for Addison's disease (rate ratio (RR) = 11.9 (95% CI 9.5 to 14.7)), Goodpasture's syndrome (RR = 10.8 (95% CI 4.0 to 23.5)), SLE (RR = 9.4 (95% CI 7.9 to 11.1)), polymyositis (RR = 8.0 (95% CI 4.9 to 12.2)), polyarteritis nodosa (RR = 6.7 (95% CI 3.2 to 12.4)), dermatomyositis (RR = 6.6 (95% CI 3.0 to 12.5)), scleroderma (RR = 6.1 (95% CI 4.4 to 8.2)) and autoimmune hemolytic anemia (RR = 5.1 (95% CI 3.4 to 7.4)). CONCLUSIONS: These two databases show that patients with some immune-mediated diseases have an increased risk of TB, although we cannot explicitly state the direction of risk or exclude confounding. Further study of these associations is warranted, and these findings may aid TB screening, control and treatment policies.
23524436 Case series of 589 tooth extractions in patients under bisphosphonates therapy. Proposal o 2013 Jul 1 OBJECTIVE: Trauma during dental surgery is a predisposing factor for bisphosphonates (BP)-related osteonecrosis of the jaws (BRONJ). However, about 40% of cases of BRONJ are not related to dental invasive procedures, being probably associated to endodontic or periodontal infections. Extraction of non-treatable teeth is considered a reliable choice, to improve symptoms and to reduce the risk of BRONJ. Here we report our experience of tooth extractions in patients under oral or intravenous BP therapy. STUDY DESIGN: Two-hundred and seventeen patients (38 males, 179 females; mean age 68.72 ± 11.26 years, range 30 to 83 years) under BP therapy received 589 tooth extractions at the Unit of Oral Medicine, Pathology and Laser-assisted Surgery of the University of Parma, Italy, between June 2006 and December 2010. Ninety five patients were under BP therapy for oncological disease (multiple myeloma (MM): 23; bone metastases (BM): 72) and 122 patients for non oncological diseases: 119 osteoporosis (OP), 2 rheumatoid arthritis (RA) and 1 Paget's disease (PD). The mean duration of BP was of 35 months. Antibiotic treatment was administered three days before and 2 weeks after tooth extractions. Patients were additionally treated with low level laser therapy (LLLT) through Nd:YAG laser (1064 nm--power 1.25 W; frequency 15 Hz; fibre diameter: 320 μm), 5 application of 1 minute each. Patients were evaluated 3 days and once a week for 2 months after the extractions and every time they received LLLT. Mean follow-up was 15 months (ranging from 4 to 31 months). RESULTS: In a total of 589 extractions (285 mandibular, 304 maxillary) performed, a minimal bone exposure was observed in 5 cases, treated with Er:YAG laser vaporization and than healed. CONCLUSIONS: Our experience supports the hypothesis that the association of antibiotic treatment and LLLT can be effective in preventing ONJ after tooth extractions in patients under BPT.
23504211 Spironolactone improves endothelial dysfunction in ankylosing spondylitis. 2013 Jul Chronic inflammation in ankylosing spondylitis (AS) is associated with vascular endothelial dysfunction which leads to accelerated atherosclerosis. Accelerated atherosclerosis contributes to premature cardiovascular disease and increased cardiovascular mortality in AS. Spironolactone inhibits the production of proinflammatory cytokines and improves endothelial dysfunction in rheumatoid arthritis. This study aimed to determine the effect of spironolactone in antitumor necrosis factor (TNF)-naive AS patients. Twenty anti-TNF-naive AS patients (M/F = 15/5) with high disease activity (Bath ankylosing spondylitis disease activity index, BASDAI >4) despite treatment with stable doses of conventional disease-modifying antirheumatic drugs were investigated. Inflammatory disease activity (BASDAI and Bath ankylosing spondylitis functional index (BASFI) scores, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels), serum nitrite concentration, and endothelium-dependent and -independent vasodilatation of the brachial artery were measured at baseline and after 12 weeks of therapy with oral spironolactone 2 mg/kg/day. Ten healthy subjects matched for age and sex acted as the control. Flow-mediated dilation (FMD) in AS patients at baseline was significantly impaired compared with healthy control group (p < 0.001). After treatment, FMD improved from 11.3 ± 1.70 to 24.69 ± 2.34% (p < 0.001); nitrite concentration reduced from 7.9 ± 0.28 to 4.79 ± 0.19 μmol/L (p < 0.001); ESR from 33.8 ± 4.38 to 15.13 ± 1.30 mm in the first hour, (p < 0.001); and CRP level from 22.39 ± 3.80 to 6.3 ± 1.29 mg/dL, (p < 0.001). BASDAI and BASFI also reduced significantly (p < 0.001). The study suggests that in AS endothelial dysfunction is a part of the disease process. This is the first study to show that treatment with spironolactone improves both endothelial dysfunction and inflammatory disease activity in AS.
23493288 The myeloperoxidase product hypochlorous acid generates irreversible high-density lipoprot 2013 May OBJECTIVE: Elevated levels of advanced oxidation protein products have been described in several chronic inflammatory diseases, like chronic renal insufficiency, rheumatoid arthritis, and atherosclerosis. Recent findings revealed that advanced oxidation protein products are inhibitors of the major high-density lipoprotein receptor, scavenger receptor class B, type 1 (SR-BI). Here, we investigated which oxidation-induced structural alterations convert plasma albumin into a high-density lipoprotein-receptor inhibitor. APPROACH AND RESULTS: Exposure of albumin to the physiological oxidant, hypochlorous acid, generated high-affinity SR-BI ligands. Protection of albumin-lysine residues before exposure to hypochlorous acid as well as regeneration of N-chloramines after oxidation of albumin completely prevented binding of oxidized albumin to SR-BI, indicating that modification of albumin-lysine residues is required to generate SR-BI ligands. Of particular interest, N-chloramines within oxidized albumin promoted irreversible binding to SR-BI, resulting in permanent receptor blockade. We observed that the SR-BI inhibitory activity of albumin isolated from chronic kidney disease patients correlated with the content of the myeloperoxidase-specific oxidation product 3-chlorotyrosine and was associated with alterations in the composition of high-density lipoprotein. CONCLUSIONS: Given that several potential atheroprotective activities of high-density lipoprotein are mediated by SR-BI, the present results raise the possibility that oxidized plasma albumin, through permanent SR-BI blockade, contributes to the pathophysiology of cardiovascular disease.
23396081 Targeting the SYK-BTK axis for the treatment of immunological and hematological disorders: 2013 May Spleen Tyrosine Kinase (SYK) and Bruton's Tyrosine Kinase (BTK) are non-receptor cytoplasmic tyrosine kinases that are primarily expressed in cells of hematopoietic lineage. Both are key mediators in coupling activated immunoreceptors to downstream signaling events that affect diverse biological functions, from cellular proliferation, differentiation and adhesion to innate and adaptive immune responses. As such, pharmacological inhibitors of SYK or BTK are being actively pursued as potential immunomodulatory agents for the treatment of autoimmune and inflammatory disorders. Deregulation of SYK or BTK activity has also been implicated in certain hematological malignancies. To date, from a clinical perspective, pharmacological inhibition of SYK activity has demonstrated encouraging efficacy in patients with rheumatoid arthritis (RA), while patients with relapsed or refractory chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) have benefited from covalent inhibitors of BTK in early clinical studies. Here, we review and discuss recent insights into the emerging role of the SYK-BTK axis in innate immune cell function as well as in the maintenance of survival and homing signals for tumor cell progression. The current progress on the clinical development of SYK and BTK inhibitors is also highlighted.
25561781 Dismicrobism in inflammatory bowel disease and colorectal cancer: changes in response of c 2014 Dec 28 Patients with inflammatory bowel disease (IBD) have an increased risk of 10%-15% developing colorectal cancer (CRC) that is a common disease of high economic costs in developed countries. The CRC has been increasing in recent years and its mortality rates are very high. Multiple biological and biochemical factors are responsible for the onset and progression of this pathology. Moreover, it appears absolutely necessary to investigate the environmental factors favoring the onset of CRC and the promotion of colonic health. The gut microflora, or microbiota, has an extensive diversity both quantitatively and qualitatively. In utero, the intestine of the mammalian fetus is sterile. At birth, the intestinal microbiota is acquired by ingesting maternal anal or vaginal organisms, ultimately developing into a stable community, with marked variations in microbial composition between individuals. The development of IBD is often associated with qualitative and quantitative disorders of the intestinal microbial flora (dysbiosis). The healthy human gut harbours about 10 different bacterial species distributed in colony forming units which colonize the gastrointestinal tract. The intestinal microbiota plays a fundamental role in health and in the progression of diseases such as IBD and CRC. In healthy subjects, the main control of intestinal bacterial colonization occurs through gastric acidity but other factors such as endoluminal temperature, competition between different bacterial strains, peristalsis and drugs can influence the intestinal microenvironment. The microbiota exerts diverse physiological functions to include: growth inhibition of pathogenic microorganisms, synthesis of compounds useful for the trophism of colonic mucosa, regulation of intestinal lymphoid tissue and synthesis of amino acids. Furthermore, mucus seems to play an important role in protecting the intestinal mucosa and maintaining its integrity. Changes in the microbiota composition are mainly influenced by diet and age, as well as genetic factors. Increasing evidence indicates that dysbiosis favors the production of genotoxins and metabolites associated with carcinogenesis and induces dysregulation of the immune response which promotes and sustains inflammation in IBD leading to carcinogenesis. A disequilibrium in gut microflora composition leads to the specific activation of gut associated lymphoid tissue. The associated chronic inflammatory process associated increases the risk of developing CRC. Ulcerative colitis and Crohn's disease are the two major IBDs characterized by an early onset and extraintestinal manifestations, such as rheumatoid arthritis. The pathogenesis of both diseases is complex and not yet fully known. However, it is widely accepted that an inappropriate immune response to microbial flora can play a pivotal role in IBD pathogenesis.
25510261 Comorbidity profiles in association with vitiligo: a nationwide population-based study in 2015 Jul BACKGROUND: The previous literature has demonstrated the association of autoimmune and atopic diseases with vitiligo, but there has been no large-scale nationwide study conducted to confirm this. OBJECTIVES: The present study was conducted to clarify the comorbid profiles in vitiligo patients and thereby better understand their clinical scenarios and underlying pathogenesis. METHODS: This was a retrospective population-based study conducted from 1996 to 2011 via the National Health Insurance Research Database in Taiwan. The differences in the prevalence of multiple autoimmune and atopic diseases between case subjects and controls were analysed by multiple logistic regression method. RESULTS: A total of 14883 vitiligo patients and 59532 controls were enroled. The prevalence of vitiligo was 0.064% and the peak of onset age was 40-59 years old. The non-stratified analysis evidenced a significant association between vitiligo and several comorbid diseases, including alopecia areata, Hashimoto thyroiditis, myasthenia gravis, psoriasis, Graves' disease, Sjögren's syndrome, systemic lupus erythematosus and atopic dermatitis. Vitiligo patients also had higher prevalence of multiple comorbidities than controls. In the age- and gender-stratified analysis, increased risks of systemic lupus erythematosus and Sjögren's syndrome were observed only in subjects aged 60-79. The association of vitiligo with myasthenia gravis and rheumatoid arthritis was identified only in the subgroup aged 20-39 and in females aged 60-79 respectively. CONCLUSION: Our study not only confirmed the significant association of vitiligo with multiple autoimmune and atopic diseases in Taiwan but also disclosed several unique findings, including the much lower prevalence of vitiligo, delayed onset of vitiligo by three decades, different associated comorbidity profiles comparing to westerners and the age- and gender-specific approach for the vitiligo-associated comorbidities.
25386048 Scropolioside B inhibits IL-1β and cytokines expression through NF-κB and inflammasome N 2014 Chronic inflammation is associated with various chronic illnesses including immunity disorders, cancer, neurodegeneration, and vascular diseases. Iridoids are compounds with anti-inflammatory properties. However their anti-inflammatory mechanism remains unclear. Here, we report that scropolioside B, isolated from a Tibetan medicine (Scrophularia dentata Royle ex Benth.), blocked expressions of TNF, IL-1, and IL-32 through NF-κB pathway. Scropolioside B inhibited NF-κB activity in a dose-dependent manner with IC50 values of 1.02 μmol/L. However, catalpol, similar to scropolioside B, was not effective in inhibiting NF-κB activity. Interestingly, scropolioside B and catalpol decreased the expression of NLRP3 and cardiolipin synthetase at both the mRNA and protein level. Our results showed that scropolioside B is superior in inhibiting the expression, maturation, and secretion of IL-1β compared to catalpol. These observations provide further understanding of the anti-inflammatory effects of iridoids and highlight scropolioside B as a potential drug for the treatment of rheumatoid arthritis and atherosclerosis.
25340460 Fc gamma receptor IIb on GM-CSF macrophages controls immune complex mediated inhibition of 2014 BACKGROUND: In rheumatoid arthritis (RA) macrophages play a major role in amplifying synovial inflammation. Important activating signals are those induced by Toll-like receptor (TLR) ligands and by activated T cells. The balance between activating and inhibitory Fc gamma receptors (FcγRs) on macrophages might be crucial in modulating these inflammatory responses. The purpose of this study was to determine FcγR expression on pro- and anti-inflammatory macrophages (gmMφ and mMφ, respectively) and identify functional consequences on immune complex uptake and macrophage activation. METHODS: Human monocytes were isolated and differentiated into gmMφ and mMφ. A full FcγR characterization of both macrophage subtypes was performed and uptake of fluorescent immune complexes (ICs) was determined. FcγRIIb isoforms were determined by qPCR. Macrophages were stimulated via different TLRs or cytokine activated T cells in the presence or absence of ICs and cytokine production was determined. Blocking studies were performed to look into the pathways involved. RESULTS: mMφ expressed high levels of the activating FcγRIIa and FcγRIII and low levels of the inhibitory FcγRIIb, while the FcγR balance on gmMφ was shifted towards the inhibitory FcγRIIb. This was accompanied by a clear increase in FcγRIIb1 mRNA expression in gmMφ. This resulted in higher IC uptake by mMφ compared to gmMφ. Furthermore, FcγR-mediated stimulation of gmMφ inhibited TLR2, 3, 4 and 7/8 mediated cytokine production via FcγRIIb and PI3K signaling. In addition, gmMφ but not mMφ produced TNFα upon co-culture with cytokine activated T cells, which was reduced by IC binding to FcγRIIb. The latter was dependent on PI3K signaling and COX2. CONCLUSIONS: FcγR expression patterns on gmMφ and mMφ are significantly different, which translates in clear functional differences further substantiating FcγRIIb as an interesting target for inflammation control in RA and other autoimmune/inflammatory diseases.