Resumo Um material endodôntico deve ser minimamente prejudicial às células-tronco, uma vez que essas células são extremamente importantes, devido à sua capacidade de proliferação, autorrenovação e diferenciação celular. Por esse motivo, a viabilidade celular e a expressão de genes envolvidos na plasticidade e diferenciação celular foram investigadas em células-tronco recuperadas de polpa dentária humana (HDPSCs) que estiveram em contato com quatro materiais endodônticos (Endofill, MTA, Pulp Canal Sealer e Sealer 26). A viabilidade das HDPSCs foi avaliada pelos ensaios MTT e de exclusão de azul de tripano. A plasticidade celular foi avaliada pela determinação das expressões dos genes CD34, CD45, Nestin, CD105, Nanog e OCT4 por PCR. O efeito na diferenciação celular foi determinado pela expressão dos genes RUNX2, ALP, OC/BGLAP e DMP1 por RT-PCR. Os dados foram analisados por ANOVA com correção de Bonferroni (p <0,05). Em comparação com o controle, Pulp Canal Sealer e Endofill diminuíram a viabilidade celular após 48 horas (p <0,001). MTA e Sealer 26 não interromperam a viabilidade celular (p> 0,05). Quando cultivado na presença de MTA e Sealer 26, as HDPSCs expressaram Nestin, CD105, NANOG e OCT-4 e não expressaram CD34 e CD45. MTA e Sealer 26 interferiram nas expressões de DMP1, OC / BGLAP e RUNX2 (p <0,05), mas não alteraram a expressão do gene ALP (p> 0,05). Sendo assim, MTA e Sealer 26 demonstraram compatibilidade biológica na presença de HDPSCs.

Abstract An endodontic material must be minimally harmful to stem cells since they are essential, thanks to their capacity for cell proliferation, self-renewal, and differentiation. For this reason, in this in vitro study, the cell viability and the expression of genes involved in cell plasticity and differentiation were investigated in stem cells recovered from human dental pulp (hDPSCs) that were in contact with four endodontic materials (Endofill, MTA, Pulp Canal Sealer, and Sealer 26). The viability of HDPSCs was assessed by MTT and trypan blue exclusion assays. PCR evaluated cellular plasticity by determining the CD34, CD45, Nestin, CD105, Nanog, and OCT4 expressions. The effect on cell differentiation was determined by RT-PCR expression of the RUNX2, ALP, OC/BGLAP, and DMP1 genes. The data were analyzed using ANOVA with Bonferroni correction (p <0.05). Pulp Canal Sealer and Endofill decreased cell viability after 48 hours (p <0.001). MTA and Sealer 26 did not disrupt cell viability (p> 0.05). When cultivated in the presence of MTA and Sealer 26, hDPSCs expressed Nestin, CD105, NANOG, and OCT-4 and did not express CD34 and CD45. MTA and Sealer 26 interfered with DMP1, OC/BGLAP and RUNX2 expressions (p <0.05) but did not change ALP gene expression (p> 0.05). MTA and Sealer 26 showed biological compatibility in the presence of hDPSCs.

Abstract: The objective of this study was to compare the periradicular responses in endodontic infections among members of two populations: an urban Brazilian population and a non-mixed indigenous population. Samples were collected immediately and 7 days after the cleaning and shaping procedures (after reducing the intracanal microbial load) in an attempt to characterize the expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-9, interferon (IFN)-γ, IL-17, IL-10, and the chemokines CXCR4, CCL2/monocyte chemotactic protein (MCP)-1, and CCR6. The endogenous cytokine and chemokine expression levels were analyzed using real-time PCR. Only the urban population showed a significant increase in TNF-α, CCL2/MCP-1, CXCR4, and CCR6 expression following the cleaning and shaping of the root canal system. The IFN-γ levels were increased at the 2nd collection (p < 0.05) in the indigenous population. In turn, a significant increase in IL-10 and IL-17 expression (p < 0.05) was observed after the cleaning and shaping procedures (2nd collection) in both populations. No significant differences in the IL-1β, IL-9, and CCL4 expression levels were observed between the 1st and 2nd collections in both populations. The results demonstrate a cytokine and chemokine expression profile that is specific to each analyzed population. However, immune modulation mediated by IL-10 began on the 7th day after the beginning of the endodontic treatment in both populations.

Abstract: The objective of this study was to analyze the epidemiological profile of oral health of Sateré-Mawé indigenous people living in Barreirinha, Amazonas (AM), Brazil, and the Tikuna indigenous people living in the urban area of Manaus (AM), in addition to characterizing the need for endodontic treatment between the two ethnic groups. A total of 138 individuals participated in the study, of whom 98 were Tikuna and 40 were Sateré-Mawé; they were distributed in age groups ranging from seven to 75 years. A very high prevalence of caries was observed in both ethnic groups. For the Sateré-Mawé in the 7–12 age group, the decayed, missing, and filled teeth (DMFT) index presented a mean value of 3.17. Comparing the DMFT index and the need for endodontic treatment in each of the ethnicities, these variables were found to be correlated, because as the DMFT index increases, the chances of needing endodontic treatment increase. The Sateré-Mawé presented a higher prevalence of need for endodontic treatment compared to the Tikuna. The association of comorbidities and the need for endodontic treatment were demonstrated only in the Tikuna, and there was only a correlation of this necessity with the presence of diabetes mellitus (DM) in one case. The need to expand access to oral health in these communities is emphasized, taking into account geographical access and technological, environmental, linguistic, and cultural barriers.

Abstract The present study aims to evaluate the longitudinal effects of induced experimental infections in gnotoxenic animals on the expression of inflammatory chemokines and their receptors in periradicular tissues. The null hypothesis tested was that Enterococcus faecalis and Fusobacterium nucleatum had no effect on CCR5, CCL5, CXCL10, CCL2/MCP-1, CXCR2 and CCR1 expression. Two groups of five animals (n = 5) aged between 8 and 12 weeks were used in this study. The animals were anaesthetized, and coronary access was performed in the first molar on the right and left sides. Microorganisms were inoculated into the left molar, and the right molar was sealed without contamination to function as a control. Animals were sacrificed 7 and 14 days after infection, and periapical tissues were collected. The cytokine mRNA expression levels were assessed using real-time PCR. The chemokine mRNA expression levels demonstrated that the experimental infection was capable of inducing increased chemokine expression on day 7 compared to that on day 14, except for CCR5 and CCL5, which showed no changes. The gnotoxenic animal model proved to be effective and allowed evaluation of the immune response against a known infection. Additionally, this study demonstrates that gene expression of chemokines and their receptors against the experimental infection preferentially prevailed during the initial phase of induction of the periradicular alteration (i.e., on day 7 post-infection).

Abstract The aim of this study is to investigate the relationship between the epidemiological and clinical profiles of patients before and after hematopoietic stem cell transplantation (HSCT) and the need for endodontic treatment. The subjects included 188 individuals enrolled in the dental care program for transplanted patients of the School of Dentistry, Federal University of Minas Gerais (Faculdade de Odontologia da Universidade Federal de Minas Gerais, FO-UFMG) from March 2011 through March 2016. The patients were subjected to an HSCT conditioning dental regimen based on a thorough clinical and radiographic evaluation. Intraoral periapical and bite-wing X-rays were obtained, and after evaluation, specific dental treatment was planned and performed. The following demographic and clinical data were collected from the patients’ medical records: age, gender, transplantation stage, primary disease, transplant type, medication used, complete blood count at the time of visit, and need for endodontic treatment. The Kolmogorov-Smirnov and the chi-square tests were used. Leukemia (31.3%) and multiple myeloma (17.9%) were the most prevalent primary diseases. Most patients were subjected to allogeneic-related transplantation (83.6%). Most patients exhibited platelet counts and hemoglobin concentrations below the reference values in the pre-transplantation stage, while the neutrophil and platelet counts and the hemoglobin levels were within the reference ranges in the post-transplantation stage. The proportions of individuals requiring endodontic treatment were similar between the pre- and post-transplantation groups: 24.3% and 24.7%, respectively. The systemic conditions of the patients referred for dental treatment were compromised.

<p>O objetivo desse artigo foi avaliar a expressão das citocinas induzidas por MTA após a perfuração experimental de furca, em camundongos. Camundongos Balb/c (n=5) foram submetidos à perfuração induzida da furca do primeiro molar superior, seguido pelo selamento da mesma com MTA no lado esquerdo (grupo experimental) e com parafina no lado direito (grupo controle). Os animais foram sacrificados 7, 14 e 21 dias após o tratamento da perfuração. A expressão gênica dos níveis de IFN-γ, TNF- α, IL-10, IL-4, TGF- β e RANKL foram investigadas por PCR em tempo real nos dentes e tecidos adjacentes. No grupo experimental, após 7 dias, houve uma diminuição da expressão dos níveis de TNF- α e IL-4 comparados ao 14° dia (p<0,05). Nesses mesmos grupos, os níveis de mRNA de RANKL, IFN- γ e TNF- α foram estatisticamente maiores após 14 dias comparados a 21 dias após o tratamento com MTA (p<0,05). Os níveis de IL-10 estavam aumentados no 21^o dia (p<0,05). A expressão de mRNA do TGF- β não apresentou alteração estatisticamente relevante. Houve uma redução estatística da expressão gênica da IL-4 quando os grupos controle e experimental foram comparados nos dias 7 e 21. Em conclusão, o selamento com MTA favoreceu a expressão de citocinas pró-inflamatórias na fase intermediária da resposta imuno-inflamatória (14^o dia). A redução dessas citocinas, na fase tardia da resposta, ocorreu provavelmente devido à imunoregulação da expressão de IL-10.</p>

<p>The aim of this study was to evaluate mineral trioxide aggregate (MTA)-induced cytokine expression in mice after experimental furcal perforation. BALB/c mice (n=5) were subjected to induced furcal drilling of the maxillary first molar followed by MTA sealing in the left side (experimental group) and paraffin sealing in the right side (control group). Animals were euthanized at 7, 14 and 21 days after sealing the perforations. The expression levels of the IFN-γ, TNF-α, IL-10, IL-4, TGF-β and RANKL genes were investigated by real time polymerase chain reaction (PCR) in the teeth and surrounding tissues. In the experimental groups, after the 7th day, there was a down-regulation of the mRNA levels of TNF-α and IL-4 compared to the 14th day (p<0.05). In these groups, the mRNA levels of RANKL, IFN-γ and TNF-α were statistically higher after 14 days compared to 21 days post-MTA sealing (p<0.05). The level of IL-10 mRNA was increased at the 21st day (p<0.05). The mRNA expression of TGF-β did not exhibit any statistically relevant results. There was a statistical down-regulation of IL-4 gene expressions when control and experimental groups were compared at days 7 and 21. In conclusion, MTA sealing favored the expression of pro-inflammatory cytokines in the intermediate phase of the immuno-inflammatory response (14th day). The reduction of these cytokines in later phase of the response was probably due to immunoregulation by IL-10.</p>

A model of skin infection with Leishmania amazonensiswith low doses of parasites is compared to infection with high doses of L. amazonensis and low and high doses of Leishmania major. C57BL/6 mice were infected with 10³ or 10(6) parasites in the ear and the outcome of infection was assessed. The appearance of lesions in mice infected with 10³ parasites was delayed compared to mice infected with 10(6) Leishmania and parasites were detectable at the infection site before lesions became apparent. Mice infected with L. amazonensisdisplayed persistent lesions, whereas infection with L. major spontaneously healed in all groups, although lymphocytes persisted at the site of infection after healing. Macrophages persisted only in L. amazonensis-infected mice. High-dose L. amazonensis-infected mice produced lower levels of IFN-γ and TNF than mice infected with L. major. No correlation between the persistence of parasites and IL-10 levels and the production of nitric oxide or urea by macrophages was found. We conclude that infection with low doses of L. amazonensisin the dermis changes the course of infection by delaying the appearance of lesions. However, low-dose infection does not change the outcomes of susceptibility and cytokine production described for subcutaneous infection with high numbers of parasites.

We describe the relationship between lesion outcome and histopathological hallmarks in susceptible (BALB/c) and resistant (C57BL/6 and IL-4-deficient BALB/c) mouse strains over the course of a 12-week-infection with Leishmania major in the ear. The infiltration of mononuclear cells and polymorphonuclear cells occurred within 6 h and mononuclear cells predominated one week post-infection. Permissive intracellular growth of the pathogen was associated with non-healing lesions. In contrast, tissue damage and clearance of the parasite was observed in healing lesions and was associated with inducible nitric oxide synthase expression. The identification of the structural components of tissue reaction to the parasite in this study furthers our understanding of subjacent immune effector mechanisms.

Resistance to infection by Leishmania major has been associated with the development of a Th1 type response that is dependent on the presence of interleukin 12 (IL-12). In this work the involvement of this cytokine in the response to infection by L. braziliensis, a less virulent species in the mouse model, was evaluated. Our results show that while interferon (IFN<FONT FACE=Symbol>-g</FONT>) deficient (-/-) mice inoculated L. braziliensis develop severe uncontrolled lesions, chronic lesions that remained under control up to 12 weeks of infection were observed in IL-12p40 -/- mice. IL 12p40 -/- mice had fewer parasites in their lesions than IFN<FONT FACE=Symbol>-g</FONT>-/- mice. Lymph node cells from IL-12p40 -/- were capable of producing low but consistent levels of IFN<FONT FACE=Symbol>-g</FONT> suggestive of its involvement in parasite control. Furthermore, as opposed to previous reports on L. major-infected animals, no switch to a Th2 response was observed in IL-12p40 -/- infected with L. braziliensis.

A capacidade de Lactobacillus acidophilus UFV-H2B20 de antagonizar Salmonella enterica subsp. enterica ser. Typhimurium, e de reduzir as conseqüências patológicas para o hospedeiro foram determinadas em animais convencionais e gnotobióticos. Camundongos NIH convencionais receberam diariamente, por via oral, 0,1 ml de uma suspensão contendo em torno de 10(8) ufc de L. acidophilus UFV-H2B20 e os animais sem germes receberam uma única dose de 0,1 ml. Os grupos gnotobióticos e convencionais foram desafiados oralmente com, respectivamente, 10² e 10(5) ufc de S. Typhimurium 7 dias após o início do tratamento. Os grupos controles foram tratados com salina estéril em vez do Lactobacillus. Dados de sobrevida mostraram um efeito protetor contra a bactéria patogênica em ambos os grupos convencional e gnotobiótico tratados com o Lactobacillus. L. acidophilus UFV-H2B20 colonizou o trato digestivo dos camundongos gnotobióticos e o número de células víaveis flutuou entre 10(9) e 10(10) ufc/g de fezes. Em ambos os grupos experimental e controle, S. Typhimurium se estabeleceu rapidamente numa faixa de 10(8) a 10(10) ufc/g de fezes e se manteve em níveis elevados até os animais morreram ou serem sacrificados. Em conclusão, o tratamento prévio de camundongos com L. acidophilus UFV-H2B20 protege os animais contra a infecção experimental com S. Typhimurium mas essa proteção não se deve à uma redução das populações patogênicas nos intestinos.

The ability of Lactobacillus acidophilus UFV-H2B20 to antagonize Salmonella enterica subsp. enterica ser. Typhimurium and to reduce the pathological consequences for the host was determining using conventional and gnotobiotic animals. Conventional NIH mice received daily by gavage a 0.1 ml suspension containing about 10(8) cfu L. acidophilus UFV-H2B20 and germfree animals received a single 0.1 ml dose. The gnotobiotic and conventional groups were infected orally with 10² and 10(5) cfu of S. Typhimurium, respectively, 7 days after the beginning of treatment. Control groups were treated with sterile saline instead of Lactobacillus. Survival data showed a protective effect against the pathogenic bacteria in both conventional and gnotobiotic Lactobacillus-treated mice. L. acidophilus UFV-H2B20 colonized the digestive tract of gnotobiotic mice and the number of viable cells ranged from 10(9) to 10(10) cfu/g of faeces. In both experimental and control gnotobiotic animals, S. Typhimurium became rapidly established at a level ranging from 10(8) to 10(10) cfu/g of faeces and remained at high levels until the animals died or were sacrificed. In conclusion, the previous treatment of mice with L. acidophilus UFV-H2B20 protects the animals against the experimental infection with S. Typhimurium but this protection was not due to the reduction of the pathogenic populations in the intestines.

Neste trabalho, estudamos a infecção experimental de camundongos Suíços/NIH com Leishmania major em comparação com camundongos isogênicos C57BL/6 e BALB/c que são resistentes e suceptíveis a esta infecção, respectivamente. Camundongos Suiços mostraram lesões que se curaram espontaneamente e se restringiram ao local de inoculação. Células linfóides derivadas destes animais desenvolveram uma resposta do tipo Th1, caracterizada pela produção de níveis altos de IFN-<FONT FACE="Symbol">g</font> e níveis baixos de IL-4. Com o objetivo de estudar a importância da microbiota no desenvolvimento da leishmaniose cutânea neste modelo, camundongos Suiços sem germes foram infectados na pata com promastigotas de L. major, convencionalizados após 3 semanas de infecção e as lesões comparadas com as observadas em camundongos convencionais. Os camundongos convencionalizados apresentaram lesões significativamente maiores do que as observadas nos camundongos convencionais. A análise histopatológica das lesões de todos os animais convencionalizados mostrou abcessos de tamanhos e formas variáveis e a presença de numerosos macrófagos parasitados. Nas lesões dos camundongos convencionais não houve a formação de abscessos e foram observados poucos macrófagos parasitados. Entretanto, células de ambos os grupos experimentais desenvolveram uma resposta similar do tipo Th1, caracterizada pela produção de altos níveis de IFN-<FONT FACE="Symbol">g</font> e baixos níveis de IL-4. Neste trabalho, demonstramos que os camundongos Suíços/NIH são resistentes à infecção por L. major, com o desenvolvimento de um fenótipo do tipo Th1 e que a ausência da microbiota no início da infecção influencia significativamente o tamanho da lesão e no processo inflamatório nestes animais.

Infection of Swiss/NIH mice with Leishmania major was compared with infection in isogenic resistant C57BL/6 and susceptible BALB/c mice. Swiss/NIH mice showed self-controlled lesions in the injected foot pad. The production of high levels of interferon-<FONT FACE="Symbol">g</font> (IFN-<FONT FACE="Symbol">g</font>) and low levels of interleukin-4 (IL-4) by cells from these animals suggests that they mount a Th1-type immune response. The importance of the indigenous microbiota on the development of murine leishmaniasis was investigated by infecting germfree Swiss/NIH in the hind footpad with L. major and conventionalizing after 3 weeks of infection. Lesions from conventionalized Swiss/NIH mice were significantly larger than conventional mice. Histopathological analysis of lesions from conventionalized animals showed abscesses of variable shapes and sizes and high numbers of parasitized macrophages. In the lesions from conventional mice, besides the absence of abscess formation, parasites were rarely observed. On the other hand, cells from conventional and conventionalized mice produced similar Th1-type response characterized by high levels of IFN-<FONT FACE="Symbol">g</font> and low levels of IL-4. In this study, we demonstrated that Swiss/NIH mice are resistant to L. major infection and that the absence of the normal microbiota at the beginning of infection significantly influenced the lesion size and the inflammatory response at the site of infection.