Potential effect of platelet rich fibrin prepared under differen centrifugation protocols on stem cells from the apical papila / O potencial efeito da fibrina rica em plaquetas preparada sob diferentes protocolos de centrifugação nas células tronco da papila apical

Objetivo: Este estudo objetivou avaliar o potencial proliferativo e de diferenciação das células tronco da papila cultivadas conjuntamente com fibrina rica em plaquetas (PRF) preparados sob dois protocolos de centrifugação distintos. Material e Métodos: Protocolos padrão e avançado de PRF foram utilizados. As células foram divididas em 4 grupos: controle negativo, controle positivo, padrão (L-PRF) e avançado (A-PRF). A contagem de células e ensaio de viabilidade foram realizados para verificar a capacidade proliferativa. Coloração vermelho de alizarina S, atividade de fosfatase alcalina e imunofluorescência para o receptor ativador do fator nuclear kappa-B (RANKL) foram utilizados para avaliar o potencial osteogênico e de diferenciação celular. Resultados: Ambos os tipos de PRF aumentaram o número de células, viabilidade celular sem toxicidade o que refletiu no aumento da proliferação e diferenciação de acordo com os testes realizados. Conclusão: O grupo A-PRF aumentou significativamente a proliferação e diferenciação comparado com o grupo L-PRF.(AU)

Objectives: The present work was designed to evaluate the proliferation and differentiation potential of stem cells from the apical papilla (SCAP) seeded along with platelet rich fibrin (PRF) scaffolds prepared under two different centrifugation protocols. Materials and Methods: Standard and advanced PRF protocols were used. Cells were divided into 4 groups: negative control, positive control, standard (L-PRF) and advanced (A-PRF) groups. Cell count and cell viability assays were carried out to assess the proliferation capacity. Alizarin red S (ARS) stain, Alkaline phosphatase (ALP) activity and Receptor activator of nuclear factor-kappa B ligand (RANKL) immunofluorescence staining were used to evaluate the osteogenic potential in the differentiated cells. Results:Both types of platelet rich fibrin increased the cell count, cell viability with no cytotoxicity that was reflected on increased proliferation and differentiation in terms of the performed tests. Conclusion: A-PRF group showed significant increase in proliferation and differentiation potentials compared to L-PRF group

Systemic versus local injection of bone marrow mesenchymal stem cells on 5-fluorouracil treated parotid glands of albino rats / Injeção sistêmica e local de células tronco da medula óssea em glandula parotida de ratos albinos tratados com 5-Fluorouracil

Objective: Head and neck cancer is the sixth leading cancer by incidence worldwide and eighth by death. Recent reports revealed that, not only radiotherapy but also chemotherapy may induce xerostomia. The aim of this study was to compare the possible regenerative effect of BMSCs through systemic and local injections. Material and Methods: 52 male Albino rats were randomly divided into 4 groups: Group 1: 10 rats received 0.5 ml of PBS by injection. Group 2: 14 rats received an intraperitoneal injection of 5-FU drug. Group 3: 14 rats were injected the same dose of 5-FU then received an intraglandular transplantation of BMSCs suspended in 0.5 ml of PBS at day 1 after 5-FU administration. Group 4: 14 rats were injected the same dose of 5-FU then received an intravenous injection of BMSCs suspended in 0.5 ml of PBS via the tail vein at day 1 after 5-FU administration. Results: Histological examination showed that group 2 showed features of severe degenerative changes which increased over time. Group 3 showed increasing amelioration in the ductal structure overtime. Group 4 also showed regenerated ductal elements however concerning apoptotic changes, immunohistochemistry results revealed improvement in both group 3 and 4 over group 2 with no statistical difference between groups 3 and 4. Conclusion: Histological and immunohistochemical features in group 3 and group 4 revealed similar amelioration in regenerative potentials. On the other hand, regenerative features of both experimental groups were statistically significant as compared independently to group 1 (AU)

Objetivo: O carcinoma de cabeça e pescoço é o sexto câncer de maior incidência no mundo sendo a oitava causa de morte por cancer. Relatos recentes revelaram que não apenas a radioterapia, mas também a quimioterapia podem induzir xerostomia. O objetivo desse estudo foi comparar a possivel ação regenerative de BMSCs através de injeção local e sistêmica. Material e Métodos: 52 ratos Albino foram aleatoriamente alocados em 4 grupos: Grupo 1: 10 ratos que receberam 0.5 ml de injeção de PBS. Grupo 2: 14 ratos que receberam injeção intraperitoneal da droga 5-FU. Grupo 3: 14 ratos que foram injetados com a mesma dose de 5-FU e receberam transplante intraglandular de BMSCs ressuspendidas em 0.5mL de PBS no dia 1 após a administração do 5-FU. Grupo 4: 14 ratos que foram injetados com a mesma dose de 5-FU e receberam injeção intravenosa de BMSCs ressuspendidas em 0.5mL de PBS via veia caudal 1 dia após a administração de 5-FU. Resultados: O exame histológico demonstrou que o grupo 2 apresentou alterações degenerativas severas que se agravaram com o tempo. O Grupo 3 mostrou melhora da estrutura ductal ao longo do experimento. Group 4 também mostrou elementos ductais regenerados. Referente a alterações apoptóticas,análise imunohistoquimica mostrou melhora nos grupos 3 e 4 comparados ao grupo 2, sendo que os grupos 3 e 4 foram estatisticamente semelhantes. Conclusão: Análises histológicas e imunohistoquímicas mostram que os grupos 3 e 4 apresentam melhora no potencial regenerativo Por outro lado, os resultados observados para os dois grupos foi estatisticamente semlhante quando comparados independentemente ao grupo 1 (AU)

New scope on the relationship between rotifers and Biomphalaria alexandrina snails

Objective: To investigate the effect of rotifer internalization into snail tissue on the development of schistosomes. Methods:Susceptible laboratory-bred Biomphalaria alexandrina (B. alexandrina) snails were exposed to lab-maintained rotifers; Philodina spp., two weeks before and after being infected with Schistosoma mansoni (S. mansoni) miracidia. The consequent histopathological impact on snail tissues and cercarial biology were investigated before and after emergence from snails. Results:Contamination of B. alexandrina snails with philodina, two weeks before miracidial exposure, was found to hinder the preliminary development of S. mansoni cercariae inside the snail tissues. Furthermore, when snails were contaminated with rotifers two weeks post miracidial exposure; growth of already established cercariae was found to be retarded. The consequent influence of internalized rotifers within the snail tissue was clearly reflected on cercarial emergence, activity and infectivity along the four weeks duration of shedding. In the present study, comparison of snail histopathological findings and altered cercarial biology observed between the experimental and control groups indicated that the rotifers may have affected the levels of snail's energy reservoirs, which eventually was found to have had an adverse impact on reproduction, growth and survival of the parasite within the snail host, coupled with its performance outside the snail. Conclusions:In future biological control strategies of schistosomiasis, ritifers should be considered as a parasitic scourge of humanity.