Synthesis and Characterization of Poly(Vinyl Alcohol)-Chitosan-Hydroxyapatite Scaffolds: A Promising Alternative for Bone Tissue Regeneration.

Scaffolds can be considered as one of the most promising treatments for bone tissue regeneration. Herein, blends of chitosan, poly(vinyl alcohol), and hydroxyapatite in different ratios were used to synthesize scaffolds via freeze-drying. Mechanical tests, FTIR, swelling and solubility degree, DSC, morphology, and cell viability were used as characterization techniques. Statistical significance of the experiments was determined using a two-way analysis of variance (ANOVA) with p < 0.05. Crosslinked and plasticized scaffolds absorbed five times more water than non-crosslinked and plasticized ones, which is an indicator of better hydrophilic features, as well as adequate resistance to water without detriment of the swelling potential. Indeed, the tested mechanical properties were notably higher for samples which were undergone to crosslinking and plasticized process. The presence of chitosan is determinant in pore formation and distribution which is an imperative for cell communication. Uniform pore size with diameters ranging from 142 to 519 µm were obtained, a range that has been described as optimal for bone tissue regeneration. Moreover, cytotoxicity was considered as negligible in the tested conditions, and viability indicates that the material might have potential as a bone regeneration system.

Musculoskeletal disorders due to chikungunya virus: A real experience in a rheumatology department in Neiva, Huila.

BACKGROUND: Chikungunya (CHIKV), is an endemic RNA virus in some regions of Asia and Africa. In Colombia in 2014, its spread started explosively and quickly. The presentation of CHIKV is a febrile condition, with musculoskeletal symptoms, which can progress to erosive arthropathy and polyarticular deformity. The purpose of this study is to evaluate symptomatic and serological behaviour in patients suffering from CHIKV infection in Neiva, Huila who attend the Rheumatology clinic, and to describe the comorbidities associated with the chronic phase of the disease. METHODS: An observational, longitudinal and retrospective analysis of data collected in 410 patients afflicted with the CHIKV virus, with symptoms lasting more than 3 months, who persisted with musculoskeletal and joint symptoms. The patients were classified according to their commitment in post-viral arthralgias, polyarthritis post viral, Rheumatoid Arthritis (RA) post CHIKV, Spondyloarthritis postCHIKV, and soft tissue rheumatism. The statistical analysis was performed using SPSS software (version 24). A descriptive analysis was carried out to evaluate quantitative variables such as the mean (standard deviation), and categorical variables such as frequency (%). The categorical variables were compared using the Chi-square equation. As a statistical significance, a p less than .05 was considered. RESULTS: Of the 410 patients, 89.23% were women, with polyarticular involvement in 92.26% of the cases. Of the patients, 49.83% had osteoarthritis. At the time of the evaluation in the Rheumatology clinic, 46.3% of the cases presented persistent non-inflammatory arthralgias, and 53.7% of the patients underwent arthritis on physical examination, of which, remarkably, 20.3% met the criteria for rheumatoid arthritis postCHIKV. CONCLUSIONS: The development of musculoskeletal symptoms after CHIKV infection is a very serious public health problem, with persistent complications and long-term morbidity risk in real life. The presence of net postviral arthritis is noteworthy, however the development of postCHIKV rheumatoid arthritis usually requires more advanced pharmacological measures, including, in some cases, transition to biological therapy. The presence of symptoms of venous insufficiency in the lower limbs that developed with CHIKV infection was an incidental finding that requires a more precise study.

Musculoskeletal Disorders due to Chikungunya Virus: A Real Experience in a Rheumatology Department in Neiva, Huila. / Desórdenes musculoesqueléticos crónicos por virus Chikungunya: experiencia real en la consulta de reumatología en Neiva, Huila.

BACKGROUND: Chikungunya (CHIKV), is an endemic RNA virus in some regions of Asia and Africa. In Colombia in 2014, its spread starts explosively and quickly. The presentation of CHIKV is a febrile condition, with musculoskeletal symptoms, which can progress to erosive arthropathy and polyarticular deformity. The purpose of this study is to evaluate in patients suffering from CHIKV infection in Neiva, Huila who attend the Rheumatology clinic, the symptomatic and serological behavior, and to describe comorbidities associated to the chronic phase of the disease. METHODS: An observational, longitudinal and retrospective analysis of data collected in 410 patients afflicted with the CHIKV virus, with symptoms lasting more than 3 months, who persisted with musculoskeletal and joint symptoms. The patients were classified according to their commitment in post-viral arthralgias, polyarthritis post viral, Rheumatoid Arthritis (RA) post CHIKV, Spondyloarthritis postCHIKV, and soft tissue rheumatism. The statistical analysis was performed using SPSS software (version 24). A descriptive analysis was carried out to evaluate quantitative variables such as the mean (standard deviation), and categorical variables such as frequency (%). The categorical variables were compared using the Chi-square equation. As a statistical significance, a p less than .05 was considered. RESULTS: Of the 410 patients, 89.23% were women, with polyarticular involvement in 92.26% of the cases. Of the patients, 49.83% had osteoarthritis. At the time of the evaluation in the Rheumatology clinic, 46.3% of the cases presented persistent non-inflammatory arthralgias, and 53.7% of the patients underwent arthritis on physical examination, of which, remarkably, 20.3% met the criteria for rheumatoid arthritis postCHIKV. CONCLUSIONS: The development of musculoskeletal symptoms after CHIKV infection is a very serious public health problem, with persistent complications and long-term morbidity risk in real life. The presence of net postviral arthritis is noteworthy, however the development of postCHIKV rheumatoid arthritis usually requires more advanced pharmacological measures, including, in some cases, transition to biological therapy. The presence of symptoms of venous insufficiency in the lower limbs that developed with CHIKV infection was an incidental finding that requires a more precise study.

Bovine Decellularized Amniotic Membrane: Extracellular Matrix as Scaffold for Mammalian Skin.

Decellularized membranes (DM) were obtained from bovine amniotic membranes (BAM) using four different decellularization protocols, based on physical, chemical, and mechanical treatment. The new material was used as a biological scaffold for in vitro skin cell culture. The DM were characterized using hematoxylin-eosin assay, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR-ATR), and differential scanning calorimetry (DSC). The in vitro cytotoxicity of DM was evaluated using MTT. The efficacy of decellularization process was assessed through DNA quantification and electrophoresis. All the used protocols showed a high effectiveness in terms of elimination of native cells, confirmed by DNA extraction and quantification, electrophoresis, and SEM, although protocol IV removes the cellular contents and preserve the native extracellular matrix (ECM) architecture which it can be considered as the most effective in terms of decellularization. FTIR-ATR and DSC on the other hand, revealed the effects of decellularization on the biochemical composition of the matrices. There was no cytotoxicity and the biological matrices obtained were a source of collagen for recellularization. The matrices of protocols I, II, and III were degraded at day 21 of cell culture, forming a gel. The biocompatibility in vitro was demonstrated; hence these matrices may be deemed as potential scaffold for epithelial tissue regeneration.