Functionalized polyester-based materials as UV curable adhesives

UV curable adhesives offer major advantages in comparison to other polymeric based adhesive systems, such as fast-curing rate and control of the polymerization heat evolution, being ideal for application on damaged tissues. Herein, functionalized polymers were prepared by modifying polycaprolactone diol (PCL) with an isocyanate-functional unsaturated acrylic ester, Laromer® 9000, using two different proportions. These functionalized materials were chemically/physically characterized and, after the addition of a biocompatible photoinitiator (Irgacure® 2959), were crosslinked by UV light irradiation. Such procedure allows the obtention of flexible transparent films. Films’ properties such as swelling, hydrolytic degradation, thermal stability, surface energy and adhesive capacity were evaluated. Furthermore, to assess the applicability of the films in biomedical applications, their haemocompatibility and biocompatibility were determined using human dermal fibroblasts as model.info:eu-repo/semantics/acceptedVersio

Polyester-based photocrosslinkable bioadhesives for wound closure and tissue regeneration support

Photocrosslinkable surgical adhesives provide many advantages when compared with traditional methods used in wound closure. This work aimed to develop UV-curable biodegradable adhesives based on lactic acid and PCL oligomers. Both materials were functionalized with 2-isocyanatoethyl acrylate (AOI). Subsequently, the photoinitiator (Irgacure® 2959) was added to the blend and then, the final materials were irradiated under UV light for two different times: 30 s and 2 min. After production of adhesives, its physicochemical properties were evaluated through FTIR-ATR and TGA, as well as its rheology, dynamic water contact angle, swelling capacity and hydrolytic degradation. Furthermore, the biocompatibility of the produced adhesives was also characterized in contact with human dermal fibroblasts cells. The antimicrobial activity of the materials was assessed by using Staphylococcus aureus and Escherichia coli, as bacterial models.info:eu-repo/semantics/publishedVersio

Type B adverse drug reactions reported by an immunoallergology department

Objective: Characterization of the adverse drug reactions (ADR) reported by the immunoallergology department (IAD), Centro Hospitalar de São João (Porto), to the Northern Pharmacovigilance Centre (NPC). Methods: An observational, descriptive and retrospective study was conducted, based in a spontaneous report system. Participants were all the patients from the IAD, with suspected ADR, reported to NPC by specialists after the study was completed. Results: Studied population had a median age of 41 years, with the predominance of the female gender (73.2%). Allergic rhinitis and asthma were the most frequent comorbidities. All studied ADR were type B, 89.6% were serious, 86.4% unexpected and 2.6% associated with drugs that presented less than 2 years in the market. The most represented drug classes were the non-steroidal anti-inflammatory drugs (NSAIDs) (52.6%) and antibiotics (25.2%). Skin symptoms represented 61.2% of the reported complaints. About 52.9% of these ADR occurred in less than one hour after intake. The most frequent ADR treatment at the time of the reaction was drug interruption (86.2%), followed by the prescription of anti-histamines (42.2%). Conclusions: Reported ADR to NPC by the Drug Alert Unit were mainly serious, unexpected, associated with NSAIDs and antibiotics and related with marketing authorization medicines older than two years. These results could be very useful to develop strategies to prevent the clinical and economic consequences of ADR.publishe

Management of Psoriasis by Family Physicians: Referral Algorithm and Shared Management with Dermatology

Introduction: The implementation of models capable of improving referral quality, limiting the growth of waiting lists in hospitals, and ensuring the best possible treatment and follow-up of the psoriatic patient is of the utmost importance. Material and methods: A panel of Family Physicians and Dermatologists discussed and created a simple and effective algorithm of referral for patients with psoriasis. Results: The proposed algorithm starts when the Family Physician suspects of psoriasis. In case of diagnostic doubt, the patient should be referred to Dermatology. In case of a confirmed diagnosis, the Family Physician should assess the patient's severity and responder profile, evaluate comorbidities and assess the presence of psoriatic arthritis. If psoriasis is mild, topical treatments should be initiated, and if there is no clinical improvement or worsening of the disease, the patient should be referred to Dermatology. If psoriasis is moderate to severe, is located in high impact locations, or in pediatric age, the patient should be referred to Dermatology. In order to enable shared management in terms of follow-up and treatment of these patients, it is critical that the Family Physician has the necessary knowledge regarding the systemic treatments used in psoriasis and their side effects. Discussion and conclusion: Only a shared management of the psoriatic patient can allow for the best treatment and follow-up of these patients, a more rational use of available medical resources, thus giving the patient the best possible quality of life.Introdução: A implementação de modelos capazes de melhorar a referenciação, por forma a garantir a qualidade e precocidade do diagnóstico, o melhor tratamento e seguimento do doente psoriático é fundamental.Material e Métodos: Um painel de médicos de Medicina Geral e Familiar e Dermatologia discutiu e criou um algoritmo de referenciação simples, eficaz e célere de doentes com psoríase.Resultados: O algoritmo proposto inicia-se quando o clínico de Medicina Geral e Familiar suspeita de psoríase. Caso haja dúvidas no diagnóstico, o doente deve ser referenciado para a dermatologia. No caso de um diagnóstico confirmado, compete ao clínico de Medicina Geral e Familiar avaliar a gravidade e perfil de respondedor do doente, rastrear comorbilidades e a possibilidade de artrite psoriática. Se a psoríase for ligeira, deverão ser iniciados tratamentos tópicos, sendo que, se não houver melhoria clínica ou ocorrer agravamento da doença, o doente deverá ser referenciado para a dermatologia. Se a psoríase for considerada moderada a grave, em localizações de elevado impacto, ou em idade pediátrica, o doente deverá ser referenciado para a dermatologia. Para que o seguimento e tratamento destes doentes seja partilhado, é fundamental que o médico de Medicina Geral e Familiar tenha o conhecimento necessário sobre os tratamentos sistémicos que o doente está a fazer e os seus efeitos adversos.Discussão e Conclusão: Apenas uma gestão partilhada do doente psoriático poderá tornar possível o melhor tratamento e seguimento destes doentes, a utilização mais racional dos recursos médicos disponíveis, proporcionando ao doente a melhor qualidade devida possível.info:eu-repo/semantics/publishedVersio

PTPN22.6, a Dominant Negative Isoform of PTPN22 and Potential Biomarker of Rheumatoid Arthritis

PTPN22 is a tyrosine phosphatase and functions as a damper of TCR signals. A C-to-T single nucleotide polymorphism (SNP) located at position 1858 of human PTPN22 cDNA and converting an arginine (R620) to tryptophan (W620) confers the highest risk of rheumatoid arthritis among non-HLA genetic variations that are known to be associated with this disease. The effect of the R-to-W conversion on the phosphatase activity of PTPN22 protein and the impact of the minor T allele of the C1858T SNP on the activation of T cells has remained controversial. In addition, how the overall activity of PTPN22 is regulated and how the R-to-W conversion contributes to rheumatoid arthritis is still poorly understood. Here we report the identification of an alternative splice form of human PTPN22, namely PTPN22.6. It lacks the nearly entire phosphatase domain and can function as a dominant negative isoform of the full length PTPN22. Although conversion of R620 to W620 in the context of PTPN22.1 attenuated T cell activation, expression of the tryptophan variant of PTPN22.6 reciprocally led to hyperactivation of human T cells. More importantly, the level of PTPN22.6 in peripheral blood correlates with disease activity of rheumatoid arthritis. Our data depict a model that can reconcile the conflicting observations on the functional impact of the C1858T SNP and also suggest that PTPN22.6 is a novel biomarker of rheumatoid arthritis

Characterization of the inflammatory cell infiltrate and expression of costimulatory molecules in chronic echinococcus granulosus infection of the human liver

Background: The local immune responses to chronic echinococcal infections in various organs are largely unknown. Since the liver is the most frequently involved organ in such infections in human we aimed to characterize the inflammatory as well as immune cell infiltrate around hydatid cysts in the liver and compared to common inflammatory processes of the liver. Method: Surgical samples from the liver of 21 cystic echinococcosis (CE) patients were studied and the distribution of different types of inflammatory and immune cells were determined by immunohistochemistry. Furthermore, expression levels of costimulatory CTLA4, CD28, CD80 and CD86 molecules were measured at RNA level by PCR. Liver biopsy samples from patients with steatohepatitis (SH, n = 11) and chronic hepatitis (CH, n = 11) were used as non-inflammatory and chronic inflammatory controls, respectively. The composition and density of the inflammatory and immune cell infiltrates have been compared by using morphometry. Results: CD3+ T cells predominated the inflammatory infiltrate in all pathological processes, while in CE samples CD20+ B cells, in CH samples CD68+ macrophages were also frequent. Both myeloperoxidase (MPO) + leukocytes and CD68+ macrophages were found to be significantly decreased in CE as compared to either SH or CH samples. Concerning T cell subtypes, only CD8+ T cells were found to be significantly decreased in SH samples. CD1a + dendritic cells were almost completely missing from CE biopsies unlike in any other sample types. There were no differences detected in the mRNA expression of costimulatory molecules except decreased expression of CD28 in CE samples. Conclusion: In the hydatid lesions of the liver of chronic echinococcal infections T cell-mediated immunity seems to be impaired as compared to other types of chronic inflammatory processes, suggesting an immunosuppressive role for Echinococcus granulosus, which deserve further attentions

Reference Genes for Accurate Transcript Normalization in Citrus Genotypes under Different Experimental Conditions

Real-time reverse transcription PCR (RT-qPCR) has emerged as an accurate and widely used technique for expression profiling of selected genes. However, obtaining reliable measurements depends on the selection of appropriate reference genes for gene expression normalization. The aim of this work was to assess the expression stability of 15 candidate genes to determine which set of reference genes is best suited for transcript normalization in citrus in different tissues and organs and leaves challenged with five pathogens (Alternaria alternata, Phytophthora parasitica, Xylella fastidiosa and Candidatus Liberibacter asiaticus). We tested traditional genes used for transcript normalization in citrus and orthologs of Arabidopsis thaliana genes described as superior reference genes based on transcriptome data. geNorm and NormFinder algorithms were used to find the best reference genes to normalize all samples and conditions tested. Additionally, each biotic stress was individually analyzed by geNorm. In general, FBOX (encoding a member of the F-box family) and GAPC2 (GAPDH) was the most stable candidate gene set assessed under the different conditions and subsets tested, while CYP (cyclophilin), TUB (tubulin) and CtP (cathepsin) were the least stably expressed genes found. Validation of the best suitable reference genes for normalizing the expression level of the WRKY70 transcription factor in leaves infected with Candidatus Liberibacter asiaticus showed that arbitrary use of reference genes without previous testing could lead to misinterpretation of data. Our results revealed FBOX, SAND (a SAND family protein), GAPC2 and UPL7 (ubiquitin protein ligase 7) to be superior reference genes, and we recommend their use in studies of gene expression in citrus species and relatives. This work constitutes the first systematic analysis for the selection of superior reference genes for transcript normalization in different citrus organs and under biotic stress

CTLA4 is expressed on mature dendritic cells derived from human monocytes and influences their maturation and antigen presentation

<p>Abstract</p> <p>Background</p> <p>Dendritic cells (DCs) initiate immune responses through their direct interaction with effector cells. However, the mechanism by which DC activity is regulated is not well defined. Previous studies have shown that CTLA4 on T cells regulates DCs function by "cross-talk". We investigated whether there is an intrinsic regulatory mechanism in DCs, with CTLA4 as a candidate regulator.</p> <p>Results</p> <p>We confirmed via RT-PCR and flow cytometry the natural expression of CTLA4 on mature DCs derived from human monocytes. Approximately 8% CD1a-positive cells express CTLA4 both on surface and intracellular, whereas 10% CD1a-negative cells express CTLA4 intracellularly, but little expression was observed on the cell surface. The cross-linking of CTLA4 inhibits DCs maturation and antigen presentation in vitro, but does not inhibit endocytosis.</p> <p>Conclusions</p> <p>CTLA4 is expressed by DCs and plays an inhibitory role. CTLA4-expressing DCs may represent a group of regulatory DCs. Because of its wide distribution on different cell types, CTLA4 may play a general role in regulating immune responses.</p

Bovine Lactoferrin Counteracts Toll-Like Receptor Mediated Activation Signals in Antigen Presenting Cells

Lactoferrin (LF), a key element in mammalian immune system, plays pivotal roles in host defence against infection and excessive inflammation. Its protective effects range from direct antimicrobial activities against a large panel of microbes, including bacteria, viruses, fungi and parasites, to antinflammatory and anticancer activities. In this study, we show that monocyte-derived dendritic cells (MD-DCs) generated in the presence of bovine LF (bLF) fail to undergo activation by up-modulating CD83, co-stimulatory and major histocompatibility complex molecules, and cytokine/chemokine secretion. Moreover, these cells are weak activators of T cell proliferation and retain antigen uptake activity. Consistent with an impaired maturation, bLF-MD-DC primed T lymphocytes exhibit a functional unresponsiveness characterized by reduced expression of CD154 and impaired expression of IFN-γ and IL-2. The observed imunosuppressive effects correlate with an increased expression of molecules with negative regulatory functions (i.e. immunoglobulin-like transcript 3 and programmed death ligand 1), indoleamine 2,3-dioxygenase, and suppressor of cytokine signaling-3. Interestingly, bLF-MD-DCs produce IL-6 and exhibit constitutive signal transducer and activator of transcription 3 activation. Conversely, bLF exposure of already differentiated MD-DCs completely fails to induce IL-6, and partially inhibits Toll-like receptor (TLR) agonist-induced activation. Cell-specific differences in bLF internalization likely account for the distinct response elicited by bLF in monocytes versus immature DCs, providing a mechanistic base for its multiple effects. These results indicate that bLF exerts a potent anti-inflammatory activity by skewing monocyte differentiation into DCs with impaired capacity to undergo activation and to promote Th1 responses. Overall, these bLF-mediated effects may represent a strategy to block excessive DC activation upon TLR-induced inflammation, adding further evidence for a critical role of bLF in directing host immune function