RESUMO
Background: Platelet rich plasma (PRP) is a blood-derived source of growth factors and several cytokines, which are essential for tissue regeneration and important for wound healing due to their angiogenic, mitogenic, and chemotactic activities. To date no protocol has been established for PRP production. Standardization of this technique should consider fundamental factors such as experimental model used, blood collection method, anticoagulant choice, rotation and amount of centrifugations, elapsed time between sample activation and its clinical use in order to ensure quality and biological effects of the product. This study aimed to compare three protocols for PRP achievement in order to evaluate platelet enrichment ability and method reproducibility for further use in clinical investigations regarding PRP therapeutic properties. Materials, Methods & Results: New Zealand higid rabbits whole blood was collected in tubes containing sodium citrate. Samples were obtained through exsanguination, via abdominal aortic puncture, and separated in four aliquots designed for PRP processing and basal platelet count. The count was conducted at the time blood was collected and after every concentration protocol. Methods were tested in triplicates, and three different individuals repeated each technique for three times, reaching 27 repetitions. Selected methodologies consisted in two c
O plasma rico em plaquetas derivado de sangue autólogo é definido como um volume de plasma com uma concentração plaquetária acima dos níveis fisiológicos. É uma fonte autógena e de baixo custo de fatores de crescimento (FC). FC são moléculas bioativas fundamentais no reparo e regeneração de diversos tecidos, capazes de estimular a mitogênese, angiogênese, quimiotaxia, proliferação e diferenciação celular. Entre os fatores liberados pelas plaquetas destacam-se: Fator de Crescimento Derivado de Plaquetas (PDGF), Fator de Crescimento Transformador Beta (TGF- ), Fator de Crescimento Endotelial Vascular (VEGF) e Fator de Crescimento Epitelial (EGF). [...]
RESUMO
Background: Colitis murine models have become essential tools to investigate the molecular and cellular mechanisms that lead to inflammatory bowel disease (IBD), such as ulcerative colitis (UC). DSS-induced colitis model faithfully reproduces many of the clinical presentation and immunological disturbances observed in UC. Notwithstanding mice can show differential susceptibilities and responsiveness to dextran sodium sulfate (DSS), and varying DSS concentration and molecular weights appear to be associated with the severity of inflammation. The aim of this study was to analyze the features of mice induced colitis using different DSS concentrations and molecular weights. Materials, Methods and Results: C57BL/6 mice received 2% of high molecular weight DSS (36 000 - 50 000) in drinking water (HDSS2%) or 5% of the same molecular weight (HDSS5%); other group received 5% of low molecular weight DSS (10 000) (LDSS5%). During the 7 days of DSS administration, animals were observed for weight loss, stool consistency and presence of blood feces to determine the disease activity index (DAI). On day 8, colons were removed, measured and weighed for indirect assessment of inflammation. The tissue samples were processed for histological analysis and blood samples were collected for hematological analysis. Our results demonstrated that HDSS5% group began to show significant clinical signs sta
Background: Colitis murine models have become essential tools to investigate the molecular and cellular mechanisms that lead to inflammatory bowel disease (IBD), such as ulcerative colitis (UC). DSS-induced colitis model faithfully reproduces many of the clinical presentation and immunological disturbances observed in UC. Notwithstanding mice can show differential susceptibilities and responsiveness to dextran sodium sulfate (DSS), and varying DSS concentration and molecular weights appear to be associated with the severity of inflammation. The aim of this study was to analyze the features of mice induced colitis using different DSS concentrations and molecular weights. Materials, Methods and Results: C57BL/6 mice received 2% of high molecular weight DSS (36 000 - 50 000) in drinking water (HDSS2%) or 5% of the same molecular weight (HDSS5%); other group received 5% of low molecular weight DSS (10 000) (LDSS5%). During the 7 days of DSS administration, animals were observed for weight loss, stool consistency and presence of blood feces to determine the disease activity index (DAI). On day 8, colons were removed, measured and weighed for indirect assessment of inflammation. The tissue samples were processed for histological analysis and blood samples were collected for hematological analysis. Our results demonstrated that HDSS5% group began to show significant clinical signs sta
RESUMO
Background: Colitis murine models have become essential tools to investigate the molecular and cellular mechanisms that lead to inflammatory bowel disease (IBD), such as ulcerative colitis (UC). DSS-induced colitis model faithfully reproduces many of the clinical presentation and immunological disturbances observed in UC. Notwithstanding mice can show differential susceptibilities and responsiveness to dextran sodium sulfate (DSS), and varying DSS concentration and molecular weights appear to be associated with the severity of inflammation. The aim of this study was to analyze the features of mice induced colitis using different DSS concentrations and molecular weights. Materials, Methods and Results: C57BL/6 mice received 2% of high molecular weight DSS (36 000 - 50 000) in drinking water (HDSS2%) or 5% of the same molecular weight (HDSS5%); other group received 5% of low molecular weight DSS (10 000) (LDSS5%). During the 7 days of DSS administration, animals were observed for weight loss, stool consistency and presence of blood feces to determine the disease activity index (DAI). On day 8, colons were removed, measured and weighed for indirect assessment of inflammation. The tissue samples were processed for histological analysis and blood samples were collected for hematological analysis. Our results demonstrated that HDSS5% group began to show significant clinical signs sta
Background: Colitis murine models have become essential tools to investigate the molecular and cellular mechanisms that lead to inflammatory bowel disease (IBD), such as ulcerative colitis (UC). DSS-induced colitis model faithfully reproduces many of the clinical presentation and immunological disturbances observed in UC. Notwithstanding mice can show differential susceptibilities and responsiveness to dextran sodium sulfate (DSS), and varying DSS concentration and molecular weights appear to be associated with the severity of inflammation. The aim of this study was to analyze the features of mice induced colitis using different DSS concentrations and molecular weights. Materials, Methods and Results: C57BL/6 mice received 2% of high molecular weight DSS (36 000 - 50 000) in drinking water (HDSS2%) or 5% of the same molecular weight (HDSS5%); other group received 5% of low molecular weight DSS (10 000) (LDSS5%). During the 7 days of DSS administration, animals were observed for weight loss, stool consistency and presence of blood feces to determine the disease activity index (DAI). On day 8, colons were removed, measured and weighed for indirect assessment of inflammation. The tissue samples were processed for histological analysis and blood samples were collected for hematological analysis. Our results demonstrated that HDSS5% group began to show significant clinical signs sta
RESUMO
Background: Platelet rich plasma (PRP) is a blood-derived source of growth factors and several cytokines, which are essential for tissue regeneration and important for wound healing due to their angiogenic, mitogenic, and chemotactic activities. To date no protocol has been established for PRP production. Standardization of this technique should consider fundamental factors such as experimental model used, blood collection method, anticoagulant choice, rotation and amount of centrifugations, elapsed time between sample activation and its clinical use in order to ensure quality and biological effects of the product. This study aimed to compare three protocols for PRP achievement in order to evaluate platelet enrichment ability and method reproducibility for further use in clinical investigations regarding PRP therapeutic properties. Materials, Methods & Results: New Zealand higid rabbits whole blood was collected in tubes containing sodium citrate. Samples were obtained through exsanguination, via abdominal aortic puncture, and separated in four aliquots designed for PRP processing and basal platelet count. The count was conducted at the time blood was collected and after every concentration protocol. Methods were tested in triplicates, and three different individuals repeated each technique for three times, reaching 27 repetitions. Selected methodologies consisted in two c
O plasma rico em plaquetas derivado de sangue autólogo é definido como um volume de plasma com uma concentração plaquetária acima dos níveis fisiológicos. É uma fonte autógena e de baixo custo de fatores de crescimento (FC). FC são moléculas bioativas fundamentais no reparo e regeneração de diversos tecidos, capazes de estimular a mitogênese, angiogênese, quimiotaxia, proliferação e diferenciação celular. Entre os fatores liberados pelas plaquetas destacam-se: Fator de Crescimento Derivado de Plaquetas (PDGF), Fator de Crescimento Transformador Beta (TGF- ), Fator de Crescimento Endotelial Vascular (VEGF) e Fator de Crescimento Epitelial (EGF). [...]