1,076 research outputs found
Imaging interactions between the immune and cardiovascular systems in vivo by multiphoton microscopy
Several recent studies in immunology have used multiphoton laser-scanning microscopy to visualise the induction of an immune response in real time in vivo. These experiments are illuminating the cellular and molecular interactions involved in the induction, maintenance and regulation of immune responses. Similar approaches are being applied in cardiovascular research where there is an increasing body of
evidence to support a significant role for the adaptive immune system in vascular disease. As such, we have begun to dissect the role of T lymphocytes in atherosclerosis in real time in vivo. Here, we provide step-by-step guides to the various stages involved in visualising the migration of T cells within a lymph node and their infiltration into inflamed tissues such as atherosclerotic arteries. These methods provide an insight into the mechanisms involved in the activation and function of immune cells in vivo
Classification Criteria for Intermediate Uveitis, Non–Pars Planitis Type
Purpose: To determine classification criteria for intermediate uveitis, non-pars planitis type (IU- NPP, also known as undifferentiated intermediate uveitis) / Design: Machine learning of cases with IU-NPP and 4 other intermediate uveitides. / Methods: Cases of intermediate uveitides were collected in an informatics-designed preliminary database, and a final database was constructed of cases achieving supermajority agreement on the diagnosis, using formal consensus techniques. Cases were split into a training set and a validation set. Machine learning using multinomial logistic regression was used on the training set to determine a parsimonious set of criteria that minimized the misclassification rate among the intermediate uveitides. The resulting criteria were evaluated on the validation set. / Results: Five hundred eighty-nine of cases of intermediate uveitides, including 114 cases of IU-NPP, were evaluated by machine learning. The overall accuracy for intermediate uveitides was 99.8% in the training set and 99.3% in the validation set (95% confidence interval 96.1, 99.9). Key criteria for IU-NPP included unilateral or bilateral intermediate uveitis with neither 1) snowballs in the vitreous nor 2) snowbanks on the pars plana. Other key exclusions included: 1) multiple sclerosis, 2) sarcoidosis, and 3) syphilis. The misclassification rates for pars planitis were 0 % in the training set and 0% in the validation set, respectively. / Conclusions: The criteria for IU-NPP had a low misclassification rate and appeared to perform well enough for use in clinical and translational research
Classification Criteria for Multiple Sclerosis-Associated Intermediate Uveitis
PURPOSE:
The purpose of this study was to determine classification criteria for multiple sclerosis-associated intermediate uveitis.
DESIGN:
Machine learning of cases with multiple sclerosis-associated intermediate uveitis and 4 other intermediate uveitides.
METHODS:
Cases of intermediate uveitides were collected in an informatics-designed preliminary database, and a final database was constructed of cases achieving supermajority agreement on the diagnosis, using formal consensus techniques. Cases were split into a training set and a validation set. Machine learning using multinomial logistic regression was used in the training set to determine a parsimonious set of criteria that minimized the misclassification rate among the intermediate uveitides. The resulting criteria were evaluated in the validation set.
RESULTS:
A total of 589 cases of intermediate uveitides, including 112 cases of multiple sclerosis-associated intermediate uveitis, were evaluated by machine learning. The overall accuracy for intermediate uveitides was 99.8% in the training set and 99.3% in the validation set (95% confidence interval: 96.1-99.9). Key criteria for multiple sclerosis-associated intermediate uveitis included unilateral or bilateral intermediate uveitis and multiple sclerosis diagnosed by the McDonald criteria. Key exclusions included syphilis and sarcoidosis. The misclassification rates for multiple sclerosis-associated intermediate uveitis were 0 % in the training set and 0% in the validation set.
CONCLUSIONS:
The criteria for multiple sclerosis-associated intermediate uveitis had a low misclassification rate and appeared to perform sufficiently well enough for use in clinical and translational research
Gamma-rays from millisecond pulsars in Globular Clusters
Globular clusters (GCs) with their ages of the order of several billion years
contain many final products of evolution of stars such as: neutron stars, white
dwarfs and probably also black holes. These compact objects can be at present
responsible for the acceleration of particles to relativistic energies.
Therefore, gamma-ray emission is expected from GCs as a result of radiation
processes occurring either in the inner magnetosperes of millisecond pulsars or
in the vicinity of accreting neutron stars and white dwarfs or as a result of
interaction of particles leaving the compact objects with the strong radiation
field within the GC. Recently, GeV gamma-ray emission has been detected from
several GCs by the new satellite observatory Fermi. Also Cherenkov telescopes
reported interesting upper limits at the TeV energies which start to constrain
the content of GCs. We review the results of these gamma-ray observations in
the context of recent scenarios for their origin.Comment: 20 pages, 9 figures, will be published in Astrophysics and Space
Science Series (Springer), eds. N. Rea and D.F. Torre
Control and Characterization of Individual Grains and Grain Boundaries in Graphene Grown by Chemical Vapor Deposition
The strong interest in graphene has motivated the scalable production of high
quality graphene and graphene devices. Since large-scale graphene films
synthesized to date are typically polycrystalline, it is important to
characterize and control grain boundaries, generally believed to degrade
graphene quality. Here we study single-crystal graphene grains synthesized by
ambient CVD on polycrystalline Cu, and show how individual boundaries between
coalescing grains affect graphene's electronic properties. The graphene grains
show no definite epitaxial relationship with the Cu substrate, and can cross Cu
grain boundaries. The edges of these grains are found to be predominantly
parallel to zigzag directions. We show that grain boundaries give a significant
Raman "D" peak, impede electrical transport, and induce prominent weak
localization indicative of intervalley scattering in graphene. Finally, we
demonstrate an approach using pre-patterned growth seeds to control graphene
nucleation, opening a route towards scalable fabrication of single-crystal
graphene devices without grain boundaries.Comment: New version with additional data. Accepted by Nature Material
Extracellular Matrix Aggregates from Differentiating Embryoid Bodies as a Scaffold to Support ESC Proliferation and Differentiation
Embryonic stem cells (ESCs) have emerged as potential cell sources for tissue engineering and regeneration owing to its virtually unlimited replicative capacity and the potential to differentiate into a variety of cell types. Current differentiation strategies primarily involve various growth factor/inducer/repressor concoctions with less emphasis on the substrate. Developing biomaterials to promote stem cell proliferation and differentiation could aid in the realization of this goal. Extracellular matrix (ECM) components are important physiological regulators, and can provide cues to direct ESC expansion and differentiation. ECM undergoes constant remodeling with surrounding cells to accommodate specific developmental event. In this study, using ESC derived aggregates called embryoid bodies (EB) as a model, we characterized the biological nature of ECM in EB after exposure to different treatments: spontaneously differentiated and retinoic acid treated (denoted as SPT and RA, respectively). Next, we extracted this treatment-specific ECM by detergent decellularization methods (Triton X-100, DOC and SDS are compared). The resulting EB ECM scaffolds were seeded with undifferentiated ESCs using a novel cell seeding strategy, and the behavior of ESCs was studied. Our results showed that the optimized protocol efficiently removes cells while retaining crucial ECM and biochemical components. Decellularized ECM from SPT EB gave rise to a more favorable microenvironment for promoting ESC attachment, proliferation, and early differentiation, compared to native EB and decellularized ECM from RA EB. These findings suggest that various treatment conditions allow the formulation of unique ESC-ECM derived scaffolds to enhance ESC bioactivities, including proliferation and differentiation for tissue regeneration applications. © 2013 Goh et al
Harnessing Naturally Occurring Tumor Immunity: A Clinical Vaccine Trial in Prostate Cancer
International audienceBACKGROUND:Studies of patients with paraneoplastic neurologic disorders (PND) have revealed that apoptotic tumor serves as a potential potent trigger for the initiation of naturally occurring tumor immunity. The purpose of this study was to assess the feasibility, safety, and immunogenicity of an apoptotic tumor-autologous dendritic cell (DC) vaccine.METHODS AND FINDINGS:We have modeled PND tumor immunity in a clinical trial in which apoptotic allogeneic prostate tumor cells were used to generate an apoptotic tumor-autologous dendritic cell vaccine. Twenty-four prostate cancer patients were immunized in a Phase I, randomized, single-blind, placebo-controlled study to assess the safety and immunogenicity of this vaccine. Vaccinations were safe and well tolerated. Importantly, we also found that the vaccine was immunogenic, inducing delayed type hypersensitivity (DTH) responses and CD4+ and CD8+ T cell proliferation, with no effect on FoxP3+ regulatory T cells. A statistically significant increase in T cell proliferation responses to prostate tumor cells in vitro (p = 0.002), decrease in prostate specific antigen (PSA) slope (p = 0.016), and a two-fold increase in PSA doubling time (p = 0.003) were identified when we compared data before and after vaccination.CONCLUSIONS:An apoptotic cancer cell vaccine modeled on naturally occurring tumor immune responses in PND patients provides a safe and immunogenic tumor vaccine
Left atrial extension of metastatic lung tumor via pulmonary vein: report on the first case of Ewing sarcoma
Extension of metastatic lung tumors into the left atrium via pulmonary veins is rare. Here, we report the first case of Ewing sarcoma exhibiting such extension. A 31-year-old man with pulmonary metastasis from Ewing sarcoma presented with a mass in the left lung, extending to the left atrium through the left inferior pulmonary vein. As the patient was considered to be at risk of tumor embolism, the mass was excised surgically
Whole Blood Interferon-Gamma Responses to Mycobacterium tuberculosis Antigens in Young Household Contacts of Persons with Tuberculosis in Uganda
Due to immunologic immaturity, IFN-gamma-producing T cell responses may be decreased in young children compared to adults, thus we hypothesized that IFN-gamma responses to mycobacterial antigens in household contacts exposed to Mycobacterium tuberculosis (Mtb) would be impaired in young children relative to adults. The objective of this study was to compare whole blood IFN-gamma production in response to mycobacterial antigens between children and adults in Uganda.We studied household contacts of persons with culture-positive pulmonary tuberculosis (TB) enrolled in a cohort study conducted in Kampala, Uganda. Whole blood IFN-gamma production in response to Mtb culture-filtrate antigens was measured by ELISA and compared between infants (<2 years old, n = 80), young children (2 <5 years old, n = 216), older children (5 <15 years old, n = 443) and adults (> or =15 years old, n = 528). We evaluated the relationship between IFN-gamma responses and the tuberculin skin test (TST), and between IFN-gamma responses and epidemiologic factors that reflect exposure to Mtb, and the effect of prior BCG vaccination on IFN-gamma responses. Young household contacts demonstrated robust IFN-gamma responses comparable to those of adults that were associated with TST and known risk factors for infection. There was no effect of prior BCG immunization on the IFN-gamma response.Young children in a TB endemic setting can mount robust IFN-gamma responses generally comparable to those of adults, and as in adults, these responses correlated with the TST and known epidemiologic risk factors for Mtb infection
- …