581 resultados para giant cell hepatitis


Relevância:

20.00% 20.00%

Publicador:

Resumo:

According to some embodiments, the present invention provides a novel photovoltaic solar cell system from photovoltaic modules that are vertically arrayed in a stack format using thin film semiconductors selected from among org. and inorg. thin film semiconductors. The stack cells may be cells that are produced in a planar manner, then vertically oriented in an angular form, also termed herein tilted, to maximize the light capturing aspects. The use of a stack configuration system as described herein allows for the use of a variety of electrode materials, such as transparent materials or semitransparent metals. Light concn. can be achieved by using fresnel lens, parabolic mirrors or derivs. of such structures. The light capturing can be controlled by being reflected back and forth in the photovoltaic system until significant quantities of the resonant light is absorbed. Light that passes to the end and can be reflected back through the device by beveling or capping the end of the device with a different refractive index material, or alternatively using a reflective surface. The contacting between stacked cells can be done in series or parallel. According to some embodiments, the present invention uses a concentrator architecture where the light is channeled into the cells that contain thermal fluid channels (using a transparent fluid such as water) to absorb and hence reduce the thermal energy generation.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A candidate gene approach using type I single nucleotide polymorphism (SNP) markers can provide an effective method for detecting genes and gene regions that underlie phenotypic variation in adaptively significant traits. In the absence of available genomic data resources, transcriptomes were recently generated in Macrobrachium rosenbergii to identify candidate genes and markers potentially associated with growth. The characterisation of 47 candidate loci by ABI re-sequencing of four cultured and eight wild samples revealed 342 putative SNPs. Among these, 28 SNPs were selected in 23 growth-related candidate genes to genotype in 200 animals selected for improved growth performance in an experimental GFP culture line in Vietnam. The associations between SNP markers and individual growth performance were then examined. For additive and dominant effects, a total of three exonic SNPs in glycogen phosphorylase (additive), heat shock protein 90 (additive and dominant) and peroxidasin (additive), and a total of six intronic SNPs in ankyrin repeats-like protein (additive and dominant), rolling pebbles (dominant), transforming growth factor-β induced precursor (dominant), and UTP-glucose-1-phosphate uridylyltransferase 2 (dominant) genes showed significant associations with the estimated breeding values in the experimental animals (P =0.001−0.031). Individually, they explained 2.6−4.8 % of the genetic variance (R2=0.026−0.048). This is the first large set of SNP markers reported for M. rosenbergii and will be useful for confirmation of associations in other samples or culture lines as well as having applications in marker-assisted selection in future breeding programs.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The transfusion of platelet concentrates (PCs) is widely used to treat thrombocytopenia and severe trauma. Ex vivo storage of PCs is associated with a storage lesion characterized by partial platelet activation and the release of soluble mediators, such as soluble CD40 ligand (sCD40L), RANTES, and interleukin (IL)-8. An in vitro whole blood culture transfusion model was employed to assess whether mediators present in PC supernatants (PC-SNs) modulated dendritic cell (DC)-specific inflammatory responses (intracellular staining) and the overall inflammatory response (cytometric bead array). Lipopolysaccharide (LPS) was included in parallel cultures to model the impact of PC-SNs on cell responses following toll-like receptor-mediated pathogen recognition. The impact of both the PC dose (10%, 25%) and ex vivo storage period was investigated [day 2 (D2), day 5 (D5), day 7 (D7)]. PC-SNs alone had minimal impact on DC-specific inflammatory responses and the overall inflammatory response. However, in the presence of LPS, exposure to PC-SNs resulted in a significant dose associated suppression of the production of DC IL-12, IL-6, IL-1a, tumor necrosis factor-a (TNF-a), and macrophage inflammatory protein (MIP)-1b and storage-associated suppression of the production of DC IL-10, TNF-a, and IL-8. For the overall inflammatory response, IL-6, TNF-a, MIP-1a, MIP-1b, and inflammatory protein (IP)-10 were significantly suppressed and IL-8, IL-10, and IL-1b significantly increased following exposure to PC-SNs in the presence of LPS. These data suggest that soluble mediators present in PCs significantly suppress DC function and modulate the overall inflammatory response, particularly in the presence of an infectious stimulus. Given the central role of DCs in the initiation and regulation of the immune response, these results suggest that modulation of the DC inflammatory profile is a probable mechanism contributing to transfusion-related complications.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We sought to evaluate central corneal thickness (CCT), corneal endothelial cell density (ECD) and intraocular pressure (IOP) in patients with type 2 diabetes mellitus (DM) and to associate potential differences with diabetes duration and treatment modality in a prospective, randomized study. We measured ECD, CCT and IOP of 125 patients with type 2 DM (mean age 57.1¡11.5 years) and compared them with 90 age-matched controls. Measured parameters were analyzed for association with diabetes duration and glucose control modalities (insulin injection or oral medication) while controlling for age. In the diabetic group, the mean ECD (2511¡252 cells/mm2), mean CCT (539.7¡33.6 mm) and mean IOP (18.3¡2.5 mmHg) varied significantly from those the control group [ECD: 2713¡132 cells/mm2 (P,0.0001), CCT: 525.0¡45.3 mm (P50.003) and IOP: 16.7¡1.8 mmHg (P,0.0001)]. ECD was significantly reduced by about 32 cell/mm2 for diabetics with duration of .10 years when compared with those with duration of ,10 years (P,0.05). CCT was thicker and IOP was higher for diabetics with duration of .10 years than those with duration of ,10 years (P.0.05). None of the measured parameters was significantly associated with diabetes duration and treatment modality (P.0.05). In conclusion, subjects with type 2 DM exhibit significant changes in ECD, IOP and CCT, which, however, are not correlated with disease duration or if the patients receive on insulin injection or oral medications.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND Mental health co-morbidities are prevalent in hepatitis C (HCV), and in practice often considered a contraindication for initiation of treatment. A systematic review was conducted to explore whether and how current HCV clinical practice guidelines address pre-existing mental health co-morbidities. METHODS A review of the literature was undertaken to identify guidelines for the management of HCV, published in English, between 2002 and January 2015. Characteristics of the guidelines were recorded and key themes on mental health were summarized across predefined stages in the patient journey (diagnosis, pre-HCV drug therapy, on HCV drug therapy, post-HCV drug therapy, advanced disease or palliative care). RESULTS Twenty-five HCV clinical guidelines were included. Referral to psychiatrist is generally recommended as pre- and in-treatment assessment of mental health co-morbidities but HCV guidelines do not offer explicit instructions on how to manage mental health co-morbidities. Post-treatment assessment of mental health co-morbidities were lacking. Conclusions Current chronic HCV clinical guidelines are limited in their advice to clinicians regarding the management of mental health co-morbidities.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background Hepatitis C (HCV) was described as a “viral time bomb” due to its prevalence and potential for causing serious, life-threatening complications. The Australian’s National Hepatitis C Strategy calls for a coordinated, evidence-based approach to testing, management, care and support of HCV. This review aimed to systematically and comparatively appraise existing international HCV clinical guidelines. Methods A systematic search of bibliographic databases and reference lists from selected papers were the source of data. Inclusion criteria were latest clinical guidelines as defined by Institute of Medicine, published in English, between January 2002 and November 2014. Quality of the guidelines was independently assessed using the iCAHE instrument. Results Twenty-eight international clinical practice guidelines were included. The majority of the international guidelines were based on the same primary studies however clinical recommendations on pre- and in-treatment assessments, choice of pharmaceuticals, and dosages and duration of the same pharmaceutical agents varied considerably. This diversity was beyond what would be considered reasonable practice context variations. Furthermore, there is limited guidance on post-treatment surveillance and care. Conclusions/implications There is a need for a harmonised international consensus on the clinical management of HCV. Key message A lack of consistency among international HCV clinical guidelines may impede effective and efficient patient care.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Human genetic and animal studies have implicated the costimulatory molecule CD40 in the development of multiple sclerosis (MS). We investigated the cell specific gene and protein expression variation controlled by the CD40 genetic variant(s) associated with MS, i.e. the T-allele at rs1883832. Previously we had shown that the risk allele is expressed at a lower level in whole blood, especially in people with MS. Here, we have defined the immune cell subsets responsible for genotype and disease effects on CD40 expression at the mRNA and protein level. In cell subsets in which CD40 is most highly expressed, B lymphocytes and dendritic cells, the MS-associated risk variant is associated with reduced CD40 cell-surface protein expression. In monocytes and dendritic cells, the risk allele additionally reduces the ratio of expression of full-length versus truncated CD40 mRNA, the latter encoding secreted CD40. We additionally show that MS patients, regardless of genotype, express significantly lower levels of CD40 cell-surface protein compared to unaffected controls in B lymphocytes. Thus, both genotype-dependent and independent down-regulation of cell-surface CD40 is a feature of MS. Lower expression of a co-stimulator of T cell activation, CD40, is therefore associated with increased MS risk despite the same CD40 variant being associated with reduced risk of other inflammatory autoimmune diseases. Our results highlight the complexity and likely individuality of autoimmune pathogenesis, and could be consistent with antiviral and/or immunoregulatory functions of CD40 playing an important role in protection from MS. © 2015 Field et al.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective. To examine whether the T cell receptor (TCR) A or TCRB loci exhibit linkage with disease in multiplex rheumatoid arthritis (RA) families. Methods. A linkage study was performed in 184 RA families from the UK Arthritis and Rheumatism Council Repository, each containing at least 1 affected sibpair. The microsatellites D14S50, TCRA, and D14S64 spanning the TCRA locus and D7S509, Vβ6.7, and D7S688 spanning the TCRB locus were used as DNA markers. The subjects were genotyped using a semiautomated polymerase chain reaction-based method. Two-point and multipoint linkage analyses were performed. Results. Nonparametric single-marker likelihood odds (LOD) scores were 0.49 (P = 0.07) for D14S50, 0.65 (P = 0.04) for TCRA, 0.07 (P = 0.29) for D14S64, 0.01 (P = 0.43) for D7S509, 0.0 (P = 0.50) for Vβ6.7, and 0.0 (P = 0.50) for D7S688. By multipoint analysis, there was no evidence of linkage at TCRB (LOD score 0), and the maximum LOD score at the TCRA locus was 0.37 (at D14S50). The presence of a susceptibility locus (LOD score < -2.0) was excluded, with lambda ≤ 1.8 at TCRA and ≤1.4 at TCRB. Conclusion. These linkage studies provide no significant evidence of a major germline-encoded TCRA or TCRB component of susceptibility to RA.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The role of germline polymorphisms of the T-cell receptor A/D and B loci in susceptibility to ankylosing spondylitis was investigated by linkage studies using microsatellite markers in 215 affected sibling pairs. The presence of a significant susceptibility gene (lambda ≤ 1.6) at the TCRA/D locus was excluded (LOD score < -2.0). At the TCRB locus, there was weak evidence of the presence of a susceptibility gene (P = 0.01, LOD score 1.1). Further family studies will be required to determine whether this is a true or false-positive finding. It is unlikely that either the TCRA/D or TCRB loci contain genes responsible for more than a moderate proportion of the non-MHC genetic susceptibility to ankylosing spondylitis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Our understanding of the origin and fate of the IgE-switched B cell has been markedly improved by studies in mouse models. The immediate precursor of the IgE-switched B cell is either a relatively naive nonswitched B cell or a mature IgG-switched B cell. These 2 routes are referred to as the direct and indirect pathways, respectively. IgE responses derived from each pathway differ significantly, largely reflecting the difference in time spent in a germinal center and thus time for clonal expansion, somatic hypermutation, affinity maturation, and acquisition of a memory phenotype. The clinical and therapeutic implications for IgE responses in human subjects are still a matter of debate, largely because the immunization procedures used in the animal models are significantly different from classical atopic sensitization to allergens from pollen and mites. On the basis of the limited information available, it seems likely that these atopic IgE responses are characterized by a relatively low IgG/IgE ratio, low B-cell memory, and modest affinity maturation, which fits well with the direct switching pathway. It is still unresolved how the IgE response evolves to cover a wide epitope repertoire involving many epitopes per allergen, as well as many different allergens from a single allergen source. © 2013 American Academy of Allergy, Asthma & Immunology.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Allergic diseases are the most common chronic disease of the western world, costing $7.8 billion per year in lost productivity and medical care in Australia alone.1 IgE is central to the immunopathogenesis of allergic diseases and important advances are now being made on multiple fronts of IgE research. In particular, two groups independently invested in the generation of IgE reporter mice to address the vexing question of the route of development of the elusive IgE+ B cell.2, 3 Two new anti-IgE mAb targeting membrane IgE and cell-bound IgE have the potential to deplete the cellular source of IgE.4, 5 These could be candidates for alternative anti-IgE treatment options with advantages over current anti-IgE therapy (OmalizumAb), which depletes free serum IgE. Researchers are still intrigued by the modes of interaction of IgE with allergen, and with both its receptors; the high affinity FcεR1 on mast cells and basophils, and the low affinity, C-type lectin, IgE receptor, CD23,6 on B cells and monocytes (Figure 1a and b). A new approach to the study of the complexity of these interactions was recently reported by Reginald et al.7 on page 167 of this issue.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background Bahia grass pollen (BaGP) is a major cause of allergic rhinitis. Subcutaneous allergen-specific immunotherapy is effective for grass pollen allergy, but is unsuitable for patients with moderate to severe asthma due to the risk of anaphylaxis. T cell-reactive but IgE nonreactive peptides provide a safer treatment option. This study aimed to identify and characterize dominant CD4+ T cell epitope peptides of the major BaGP allergen, Pas n 1. Methods Pas n 1-specific T cell lines generated from the peripheral blood of BaGP-allergic subjects were tested for proliferative and cytokine response to overlapping 20-mer Pas n 1 peptides. Cross-reactivity to homologous peptides from Lol p 1 and Cyn d 1 of Ryegrass and Bermuda grass pollen, respectively, was assessed using Pas n 1 peptide-specific T cell clones. MHC class II restriction of Pas n 1 peptide T cell recognition was determined by HLA blocking assays and peptide IgE reactivity tested by dot blotting. Results Three Pas n 1 peptides showed dominant T cell reactivity; 15 of 18 (83%) patients responded to one or more of these peptides. T cell clones specific for dominant Pas n 1 peptides showed evidence of species-specific T cell reactivity as well as cross-reactivity with other group 1 grass pollen allergens. The dominant Pas n 1 T cell epitope peptides showed HLA binding diversity and were non-IgE reactive. Conclusions The immunodominant T cell-reactive Pas n 1 peptides are candidates for safe immunotherapy for individuals, including those with asthma, who are allergic to Bahia and possibly other grass pollens.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

There have been recent improvements in the clinical understanding and definition of the major types of autoimmune liver disease. However, still lacking is knowledge of their prevalence and pathogenesis. Three areas of study are in progress in our laboratory. First, in type 1 autoimmune hepatitis, the search continues to identify a liver/disease-specific autoantigenic reactant. Using hepatocyte membrane preparations, immunoblotting has underlined the problem of distinguishing, among multiple reactants, those that may be causally rather than consequentially related to hepatocellular damage. Second, in primary biliary cirrhosis (PBC), the need for population screening to ascertain prevalence and detect preclinical cases can be met by a rapid automated procedure for detection, by specific enzyme inhibition in microtitre wells, of antibody (anti-M2) to the pyruvate dehydrogenase complex E2 subunit (PDC-E2). Third, the structure of the conformational epitope within the inner lipoyl domain of PDC-E2 is being investigated by screening random phage-displayed peptide libraries using PBC sera. This has yielded phage clones in which the sequence of the peptide insert portrays the structure of this epitope, as judged by clustering of PBC-derived sequences to particular branches of a guide-tree that shows relatedness of peptides, and by reactivity of selected phage clones with anti-PDC-E2. Thus phage display identifies a peptide 'mimotope' of the antibody epitope in the inner lipoyl domain of PDC-E2.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Electrospun nanofiber meshes have emerged as a new generation of scaffold membranes possessing a number of features suitable for tissue regeneration. One of these features is the flexibility to modify their structure and composition to orchestrate specific cellular responses. In this study, we investigated the effects of nanofiber orientation and surface functionalization on human mesenchymal stem cell (hMSC) migration and osteogenic differentiation. We used an in vitro model to examine hMSC migration into a cell-free zone on nanofiber meshes and mitomycin C treatment to assess the contribution of proliferation to the observed migration. Poly (ɛ-caprolactone) meshes with oriented topography were created by electrospinning aligned nanofibers on a rotating mandrel, while randomly oriented controls were collected on a stationary collector. Both aligned and random meshes were coated with a triple-helical, type I collagen-mimetic peptide, containing the glycine-phenylalanine-hydroxyproline-glycine-glutamate-arginine (GFOGER) motif. Our results indicate that nanofiber GFOGER peptide functionalization and orientation modulate cellular behavior, individually, and in combination. GFOGER significantly enhanced the migration, proliferation, and osteogenic differentiation of hMSCs on nanofiber meshes. Aligned nanofiber meshes displayed increased cell migration along the direction of fiber orientation compared to random meshes; however, fiber alignment did not influence osteogenic differentiation. Compared to each other, GFOGER coating resulted in a higher proliferation-driven cell migration, whereas fiber orientation appeared to generate a larger direct migratory effect. This study demonstrates that peptide surface modification and topographical cues associated with fiber alignment can be used to direct cellular behavior on nanofiber mesh scaffolds, which may be exploited for tissue regeneration.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The periodontal ligament is the key tissue facilitating periodontal regeneration. This study aimed to fabricate decellularized human periodontal ligament cell sheets for subsequent periodontal tissue engineering applications. The decellularization protocol involved the transfer of intact human periodontal ligament cell sheets onto melt electrospun polycaprolactone membranes and subsequent bi-directional perfusion with NH4OH/Triton X-100 and DNase solutions. The protocol was shown to remove 92% of DNA content. The structural integrity of the decellularized cell sheets was confirmed by a collagen quantification assay, immunostaining of human collagen type I and fibronectin, and scanning electron microscopy. ELISA was used to demonstrate the presence of residual basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), and hepatocyte growth factor (HGF) in the decellularized cell sheet constructs. The decellularized cell sheets were shown to have the ability to support recellularization by allogenic human periodontal ligament cells. This study describes the fabrication of decellularized periodontal ligament cell sheets that retain an intact extracellular matrix and resident growth factors and can support repopulation by allogenic cells. The decellularized hPDL cell sheet concept has the potential to be utilized in future "off-the-shelf" periodontal tissue engineering strategies.