226 research outputs found
Anti-IgE Response in Human Airways: Relative Contribution of Inflammatory Mediators
Heman airway preparations at resting tone were relaxed with either
the leukotriene synthesis inhibitor BAY x1005 (3 μM),
chlorpheniramine (1 μM) or the thromboxane receptor antagonist
BAY u3405 (0.1 μM). The response to anti-IgE (1:1000) was 58
± 8% of acetylcholine pre-contraction (2.19 ±
0.28 g). Indomethacin (3 μM) enhanced the anti-IgE-induced
contraction by 28%. The anti-IgE maximal response was not
modified by either chlorpheniramine, BAY x1005 or BAY u3405. When
the tissues were treated with either BAY xl005/indomethacin or
BAY x1005/chlorpheniramine, the anti-IgE-induced contraction was
reduced. In addition, in presence of BAY
xl005/indomethacin/chlorpheniramine the response was
completely blocked. These results suggest that mediatots released
during anti-IgE challenge cause airway contraction which may mask
the evaluation of the leukotriene component
Idiopathic Multifocal Choroiditis and Punctate Inner Choroidopathy - Evaluation of Risk Factors for Increased Relapse Rate: A 2-Year Prospective Observational Cohort Study
Introduction: The aim of this study was to describe the course of disease in patients with idiopathic multifocal choroiditis (MFC) and punctate inner choroidopathy (PIC) and to identify risk factors associated with an increased relapse rate of disease activity. Methods: In this prospective observational cohort study, demographical and clinical data were collected concerning the relapses rate of disease activity, the conclusions of the multimodal imaging results, treatment, complications, and self-reported quality of life. Disease activity was defined as new inflammatory lesions or active inflammation in preexisting chorioretinal lesions either with or without active choroidal neovascularization (CNV). Linear regression analysis was performed to identify risk factors associated with an increased relapse rate. Results: In total, 122 eyes of 82 patients (93% females) were included with a median age (IQR) of 45 (37-54) years. A history of secondary CNV was present in 66% of the eyes. During follow-up, the best-corrected visual acuity remained stable despite a median relapse rate (IQR) of 1.0 (0.25-3). Cycles of oral corticosteroids were given in 59% of the patients, 72% were treated at baseline or started treatment during follow-up with a disease-modifying antirheumatic drug (DMARD), and 35% with a biological agent in addition to the DMARD. Both a history of secondary CNV (B = 1.2, 95% CI: 0.7-1.7, p = 3.6 × 102) and high myopia (<-6 diopters) (B = 0.6, 95% CI: 0.1-1.1, p = 0.02) independently increased the relapse rate of disease activity. Discussion/Conclusion: A history of secondary CNV and high myopia were associated with an increased relapse rate of disease activity. Moreover, the results of this study emphasize the challenging character of treating patients with MFC/PIC
Bronchodilation induced by PGE2 is impaired in Group-III pulmonary hypertension
BACKGROUND AND PURPOSE: In patients with pulmonary hypertension (PH) associated with lung disease and/or hypoxia (Group III), a reduction of pulmonary vascular tone and tissue hypoxia are considered therapeutically beneficial. Prostaglandin (PG) E2 and PGI2 induce potent relaxation of human bronchi from non-PH (control) patients via EP4 and IP receptors, respectively. However, the effects of PGE2 /PGI2 and their mimetics on human bronchi from PH-patients are unknown. Our aim was to compare the relaxant effects of several PGI2 -mimetics approved for treating PH-Group I with several PGE2 -mimetics in bronchial preparations derived from PH-Group III and control patients. EXPERIMENTAL APPROACH: Using an organ bath system, the tone of bronchial muscle was investigated in tissue from either control or PH-Group III patients. Expression of prostanoid receptors were analyzed by Western blot and real-time PCR and endogenous PGE2 , PGI2 and cAMP levels were determined by ELISA. KEY RESULTS: Maximal relaxations induced by different EP4 agonists (PGE2 , L-902688, ONO-AE1-329) were significantly decreased in human bronchi from PH-patients versus controls. In contrast, the maximal relaxations produced by PGI2 -mimetics (iloprost, treprostinil, beraprost) were similar for both groups of patients. Both EP4 and IP receptor protein and mRNA expressions were significantly lower in human bronchi from PH-patients. cAMP levels significantly correlated with PGI2 but not with PGE2 levels. CONCLUSION AND IMPLICATIONS: This study shows that PGI2 -mimetics have preserved maximal bronchodilation in PH-Group III patients. The decreased bronchodilation induced by EP4 agonists suggests that restoration of EP4 expression in airways of PH-patients with respiratory diseases could bring additional therapeutic benefit
Computation of protein geometry and its applications: Packing and function prediction
This chapter discusses geometric models of biomolecules and geometric
constructs, including the union of ball model, the weigthed Voronoi diagram,
the weighted Delaunay triangulation, and the alpha shapes. These geometric
constructs enable fast and analytical computaton of shapes of biomoleculres
(including features such as voids and pockets) and metric properties (such as
area and volume). The algorithms of Delaunay triangulation, computation of
voids and pockets, as well volume/area computation are also described. In
addition, applications in packing analysis of protein structures and protein
function prediction are also discussed.Comment: 32 pages, 9 figure
The efficacy of corticosteroid-sparing immunomodulatory therapy in treating patients with central multifocal choroiditis
Purpose: To evaluate the efficacy of corticosteroid-sparing immunomodulatory therapy (IMT) in patients with recurrent and/or sight-threatening central multifocal choroiditis (MFC). Methods: This was a retrospective cohort study in a tertiary uveitis centre including all patients with MFC who have been treated with IMT for at least 12 months. Clinical data and imaging results were collected regarding the period prior to the start of IMT and at 3, 6, 12 and – where available – 24 months after the start of IMT. Main outcome measure was the number of annual recurrences of choroiditis with or without active choroidal neovascularization before and after the start of IMT. Secondary outcomes were the percentage of patients with (steroid-free) remission and the median time between the start of IMT and (steroid-free) remission. Results: Thirty-two patients (39 eyes) were included. At the start of IMT, none of the patients were in (steroid-free) remission. At 24 months, the probability of achieving remission and steroid-free remission was 88,5% and 50%, respectively. The median time to achieve remission and steroid-free remission was 21 and 83 weeks, respectively. In 17 patients (20 eyes) with available clinical data and imaging results for ≥ 12 months prior to the start of IMT, the mean number of recurrences/year decreased significantly from 1.40 ± 0.81 at baseline to 0.49 ± 0.47 (p = 0.001) after the start of IMT. Conclusions: Preventive therapy with IMT should be considered in patients with recurrent and/or sight-threatening MFC to decrease the number of recurrences/year and to increase the prospects of achieving either remission or steroid-free remission
International Union of Basic and Clinical Pharmacology: Differences and similarities between human and rodents concerning prostaglandin EP1-4 and IP receptors: Specific roles in pathophysiologic conditions
Prostaglandins are derived from arachidonic acid metabolism through cyclooxygenase activities. Among prostaglandins (PGs), prostacyclin (PGI(2)) and PGE(2) are strongly involved in the regulation of homeostasis and main physiologic functions. In addition, the synthesis of these two prostaglandins is significantly increased during inflammation. PGI(2) and PGE(2) exert their biologic actions by binding to their respective receptors, namely prostacyclin receptor (IP) and prostaglandin E-2 receptor (EP) 1-4, which belong to the family of G-protein-coupled receptors. IP and EP1-4 receptors are widely distributed in the body and thus play various physiologic and pathophysiologic roles. In this review, we discuss the recent advances in studies using pharmacological approaches, genetically modified animals, and genome-wide association studies regarding the roles of IP and EP1-4 receptors in the immune, cardiovascular, nervous, gastrointestinal, respiratory, genitourinary, and musculoskeletal systems. In particular, we highlight similarities and differences between human and rodents in terms of the specific roles of IP and EP1-4 receptors and their downstream signaling pathways, functions, and activities for each biologic system. We also highlight the potential novel therapeutic benefit of targeting IP and EP1-4 receptors in several diseases based on the scientific advances, animal models, and human studies
Understanding the limits of animal models as predictors of human biology: lessons learned from the sbv IMPROVER Species Translation Challenge
Motivation: Inferring how humans respond to external cues such as drugs, chemicals, viruses or hormones is an essential question in biomedicine. Very often, however, this question cannot be addressed because it is not possible to perform experiments in humans. A reasonable alternative consists of generating responses in animal models and ‘translating' those results to humans. The limitations of such translation, however, are far from clear, and systematic assessments of its actual potential are urgently needed. sbv IMPROVER (systems biology verification for Industrial Methodology for PROcess VErification in Research) was designed as a series of challenges to address translatability between humans and rodents. This collaborative crowd-sourcing initiative invited scientists from around the world to apply their own computational methodologies on a multilayer systems biology dataset composed of phosphoproteomics, transcriptomics and cytokine data derived from normal human and rat bronchial epithelial cells exposed in parallel to 52 different stimuli under identical conditions. Our aim was to understand the limits of species-to-species translatability at different levels of biological organization: signaling, transcriptional and release of secreted factors (such as cytokines). Participating teams submitted 49 different solutions across the sub-challenges, two-thirds of which were statistically significantly better than random. Additionally, similar computational methods were found to range widely in their performance within the same challenge, and no single method emerged as a clear winner across all sub-challenges. Finally, computational methods were able to effectively translate some specific stimuli and biological processes in the lung epithelial system, such as DNA synthesis, cytoskeleton and extracellular matrix, translation, immune/inflammation and growth factor/proliferation pathways, better than the expected response similarity between species. Contact: [email protected] or [email protected] Supplementary information: Supplementary data are available at Bioinformatics onlin
The efficacy of adalimumab in treating patients with central multifocal choroiditis
Purpose: To evaluate the efficacy of adalimumab in patients with central multifocal choroiditis (cMFC) refractory to conventional corticosteroid-sparing immunomodulatory agents (IMT). Methods: Medical records were reviewed from all patients with cMFC and treated with adalimumab with follow-up of at least 12 months. The study focused on the 12 months prior to and after the start of adalimumab. The imaging results were independently evaluated by two ophthalmologists. The main outcomes were the number of patients without a relapse of disease activity in 12 months after the start of adalimumab and the ability to stop the systemic corticosteroids to evaluate the corticosteroid-sparing effect. Results: Twelve patients (18 eyes) were included. In 8/12 (67%) patients no relapse of disease activity was observed in the 12 months after the start of adalimumab. In 9/12 patients the systemic corticosteroid treatment could be stopped and in an additional 2 patients tapered to ≤7,5mg daily. In the 12 months before the start of adalimumab, the patients experienced a median of 3 (range 2–4) relapses of disease activity. Nine patients experienced relapses while treated with a combination of systemic corticosteroids (mean dose 13,6 mg; range 5–25 mg) and IMT. Moreover, 3 patients treated with IMT, experienced relapses after tapering and stopping the systemic corticosteroids. In all eyes (n = 5) with CNV before the start of adalimumab, the intravitreal anti-VEGF injections could be stopped after the start of adalimumab. Conclusions: AND IMPORTANCE: Adalimumab may be effective in patients with cMFC refractory to IMT and may be considered as a treatment option in patients with cMFC
Exploring Imaging Characteristics Associated With Disease Activity in Idiopathic Multifocal Choroiditis: A Multimodal Imaging Approach
Purpose: To identify characteristics on multimodal imaging (MMI) in idiopathic multifocal choroiditis (MFC) that can identify inflammatory activity and distinguish choroidal neovascularization (CNV) activity from inflammatory activity. Design: Prospective cohort study. Methods: MMI consisted of spectral-domain optical coherence tomography (angiography) (SD-OCT(A)), fundus autofluorescence, fundus photography, infrared imaging, fluorescein angiography (FA), and indocyanine green angiography (ICGA). MMI characteristics obtained during active and inactive disease were compared within the same lesion. Secondly, MMI characteristics were compared between active inflammatory lesions with and without CNV activity. Results: Fifty patients (110 lesions) were included. In 96 lesions without CNV activity, the mean focal choroidal thickness was increased during the active disease (205 µm) compared to the inactive disease (180 µm) (P ≤ .001). Lesions with inflammatory activity typically demonstrated moderately reflective material located in the sub–retinal pigment epithelium (RPE) and/or in the outer retina with disruption of the ellipsoid zone. During the inactive stage of the disease, the material disappeared or became hyperreflective and indistinguishable from the RPE. During the active stage of the disease, the area of hypoperfusion in the choriocapillaris significantly increased as visualized on both ICGA and SD-OCTA. CNV activity in 14 lesions was associated with subretinal material with a mixed reflectivity and hypotransmission of light to the choroid on SD-OCT and leakage on FA. SD-OCTA identified vascular structures in all active CNV lesions and in 24% of lesions without CNV activity (showing old, quiescent CNV membranes). Conclusion: Inflammatory activity in idiopathic MFC was associated with several MMI characteristics, including focally increased choroidal thickness. These characteristics can guide clinicians in the challenging process of the evaluation of disease activity in idiopathic MFC patients
- …