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One of the main challenges of tissue engineering in dentistry is to replace bone and dental tissues with strategies or techniques that simulate physiological tissue repair conditions. This systematic review of in vitro studies aimed to evaluate the influence of the addition of nanohydroxyapatite (NHap) to scaffolds on cell proliferation and osteogenic and odontogenic differentiation of human mesenchymal stem cells. In vitro studies on human stem cells that proliferated and differentiated into odontogenic and osteogenic cells in scaffolds containing NHap were included in this study. Searches in PubMed/MEDLINE, Scopus, Web of Science, OpenGrey, ProQuest, and Cochrane Library electronic databases were performed. The total of 333 articles was found across all databases. After reading and analyzing titles and abstracts, 8 articles were selected for full reading and extraction of qualitative data. Results showed that despite the large variability in scaffold composition, NHap-containing scaffolds promoted high rates of cell proliferation, increased alkaline phosphatase (ALP) activity during short culture periods, and induced differentiation, as evidenced by the high expression of genes involved in osteogenesis and odontogenesis. However, further studies with greater standardization regarding NHap concentration, type of scaffolds, and evaluation period are needed to observe possible interference of these criteria in the action of NHap on the proliferation and differentiation of human stem cells.

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One of the main challenges of tissue engineering in dentistry is to replace bone and dental tissues with strategies or techniques that simulate physiological tissue repair conditions. This systematic review of in vitro studies aimed to evaluate the influence of the addition of nanohydroxyapatite (NHap) to scaffolds on cell proliferation and osteogenic and odontogenic differentiation of human mesenchymal stem cells. In vitro studies on human stem cells that proliferated and differentiated into odontogenic and osteogenic cells in scaffolds containing NHap were included in this study. Searches in PubMed/MEDLINE, Scopus, Web of Science, OpenGrey, ProQuest, and Cochrane Library electronic databases were performed. The total of 333 articles was found across all databases. After reading and analyzing titles and abstracts, 8 articles were selected for full reading and extraction of qualitative data. Results showed that despite the large variability in scaffold composition, NHap-containing scaffolds promoted high rates of cell proliferation, increased alkaline phosphatase (ALP) activity during short culture periods, and induced differentiation, as evidenced by the high expression of genes involved in osteogenesis and odontogenesis. However, further studies with greater standardization regarding NHap concentration, type of scaffolds, and evaluation period are needed to observe possible interference of these criteria in the action of NHap on the proliferation and differentiation of human stem cells.

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Fungi exhibit three adverse effects on human health: inflammatory, allergic and toxic effects, these implications affect mainly immunodepressed patients. The objective of this work was to analyze the fungal microbiota of the ambient air of an Intensive Care Unit. Three collections were carried out in an Intensive Care Unit in the city of Rio Branco, Acre, Western Amazon, Brazil from March to May 2017. 126 Petri dishes were exposed with the culture medium Agar Sabouraud with chloramphenicol and Agar Mycosel, considering the distribution of the 21 air conditioners, split residential model. The plates were incubated for seven days at room temperature and the growth of Colony Forming Units was observed. Colony counting and isolation for the morphological characterization of the granted fungi was performed. After quantification, the concentration of fungi per cubic meters of air (CFU.m-3) was settled. The third collection had a larger number of colony forming units with 48.6%. In the total of the analyzed samples, filamentous fungi (85.5%) and yeasts (14.5%) were isolated. Thirteen genera of fungi were identified, with the most frequent filaments being Cladosporium spp. 33.0%, Aspergillus spp. 30.4% and Penicillium spp. 19.6%, and yeasts Candida spp. 52.6%, Trichosporon spp. 36.9%. The colony-forming unit per cubic meter (CFU.m-3) did not shown any difference between the Cores in the same collection period, however in the 1st and 3rd collection, Core 1 had the highest average. The fungal microbiota of this Unit presented thirteen different genera potentially pathogenic, revealing the need for monitoring microorganisms and prevention actions.

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OBJECTIVE: To evaluate the adhesion of universal adhesive systems to the dentin of noncarious cervical lesions (NCCLs) by comparing the etch-and-rinse and self-etch strategies through a systematic review and meta-analysis. METHODS: Systematic electronic searches were performed by two independent reviewers into the following databases: PubMed/MEDLINE, Scopus, Web of Science, and Cochrane Library until December of 2021. Only randomized clinical trials were selected, comparing etch-and-rinse and self-etch strategies and using universal adhesive systems in NCCLs. This systematic review was conducted according to the PRISMA guidelines and registered into PROSPERO. RESULTS: After the removal of duplicates, 170 articles were identified. In an initial screening of titles and abstracts, 146 records did not satisfy the inclusion criteria and were, therefore, excluded. Twenty-four studies were eligible for evaluation of the full text, and four were excluded after this step. Finally, 20 randomized clinical trials were included in this systematic review and meta-analysis. CONCLUSION: This systematic review and meta-analysis revealed that applying universal adhesive systems in the etch-and-rinse strategy could lead to better medium-term (>12 to 36 months) retention of NCCL restorations than the self-etch strategy, as well as resulting in lower percentages of marginal discoloration, marginal adaptation, and secondary caries. However, the use of a self-etching strategy can lead to lower postoperative sensitivity.

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Ganoderma lucidum is a medicinal mushroom widely recognized as a source of biomolecules with pharmacological properties, however, little is known about the factors that influence the synthesis of bioactive proteins by this fungus when cultivated under submerged fermentation. The objective of this work was to evaluate the production of mycelial biomass and intracellular proteases and protease inhibitors by G. lucidum cultivated under different submerged fermentation conditions. The cultivation was carried out in a medium composed of glucose (10 or 20 g.L-1), soy peptone (2.5 or 5 g.L-1) and yeast extract (5 g.L-1), with incubation under agitation (120 rpm) and non-agitation, totaling 8 experimental conditions. Biomass production was determined from the dry weight, while glucose consumption was estimated by quantification of reducing sugars. The proteins were extracted in NaCl (0.15 M), and the protein extracts were submitted to protein quantification by the Bradford method, total proteolytic activity using azocasein, caseinolytic and fibrinolytic activity in Petri dishes, activity of serine (trypsin and chymotrypsin) and cysteine (papain) protease inhibitors. Cultivation in agitated condition showed higher biomass production with a maximum value of 7 g.L-1, in addition to higher activities of trypsin, chymotrypsin and papain inhibitors, with 154 IU.mg-1, 153 IU.mg-1 e 343 IU.mg-1 of protein, respectively. The non-agitated condition showed a greater potential for obtaining proteins, total proteases, caseinolytic and fibrinolytic enzymes, with maximum values of 433 mg.g-1 of extract, 71 U.mL-1 of extract, 63.62 mm2 and 50.27 mm2, respectively. Thus, a medium composed of soy peptone, yest extract and glucose in a 1:2:4 proportion is recommended, under agitation to produce protease inhibitors, and the non-agitated condition when the target is, mainly caseinolytic and fibrinolytic enzymes.

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This study aimed to compare the fracture toughness of molars with wide mesio-occlusal-distal (MOD) cavities restored with regular and flowable bulk-fill resin composite and a conventional resin composite after 250,000 mechanical cycles of chewing simulation. Thirty-two extracted mandibular third molars were selected and class II MOD cavities involving 2/3 of the intercuspal width and 4 mm depth were prepared. Teeth were divided into four groups based on resin composite type and insertion technique (n=8): (1) CT, unprepared teeth (control); (2) CV, conventional resin composite (Tetric N-Ceram, Ivoclar Vivadent) with incremental technique; (3) R-BF, regular bulk-fill resin composite (Tetric N-Ceram Bulk Fill, Ivoclar Vivadent) with a single increment; and (4) F-BF, flowable bulk-fill resin composite (Tetric N-Flow Bulk Fill, Ivoclar Vivadent) with a single increment, except for a 1-mm-thick layer at the occlusal surface, restored with conventional resin composite (Tetric N-Ceram). All specimens were evaluated to detect the presence and propagation of enamel cracks using a LED transilluminator before and after 250,000 mechanical cycles (SD Mechatronic GmbH). After a chewing simulation, they were subjected to a compressive force in a universal testing machine (DL-2000, EMIC) until fracture. The maximum fracture load of the specimens was measured (N) and the fracture patterns were classified based on the fracture site (above or below the cementoenamel junction [CEJ]). Data were statistically analyzed with one-way ANOVA. All specimens survived after 250,000 mechanical cycles, and no statistically significant differences among groups were observed regarding the fracture toughness (p<0.05). The fracture analysis demonstrated that failures below the CEJ were more common in CV (75%), while CT, R-BF, and F-BF showed this type of failure in 38%, 63%, and 63% of the specimens, respectively. The results of the crack analysis showed that the occurrence of new cracks and crack propagation was also higher in CV (33.3%), followed by R-BF, F-BF, and CT (14%, 14%, and 11% of the specimens, respectively). Teeth restored with regular and flowable bulk-fill composites showed similar fracture toughness after the chewing simulation compared to those restored with the conventional resin composite and unprepared teeth. Furthermore, teeth restored with both regular and flowable bulk-fill composites showed a lower incidence of enamel cracks and fractures below the CEJ compared to those restored with the conventional resin composite.

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Ganoderma lucidum is a medicinal mushroom widely recognized as a source of biomolecules with pharmacological properties, however, little is known about the factors that influence the synthesis of bioactive proteins by this fungus when cultivated under submerged fermentation. The objective of this work was to evaluate the production of mycelial biomass and intracellular proteases and protease inhibitors by G. lucidum cultivated under different submerged fermentation conditions. The cultivation was carried out in a medium composed of glucose (10 or 20 g.L-1), soy peptone (2.5 or 5 g.L-1) and yeast extract (5 g.L-1), with incubation under agitation (120 rpm) and non-agitation, totaling 8 experimental conditions. Biomass production was determined from the dry weight, while glucose consumption was estimated by quantification of reducing sugars. The proteins were extracted in NaCl (0.15 M), and the protein extracts were submitted to protein quantification by the Bradford method, total proteolytic activity using azocasein, caseinolytic and fibrinolytic activity in Petri dishes, activity of serine (trypsin and chymotrypsin) and cysteine (papain) protease inhibitors. Cultivation in agitated condition showed higher biomass production with a maximum value of 7 g.L-1, in addition to higher activities of trypsin, chymotrypsin and papain inhibitors, with 154 IU.mg-1, 153 IU.mg-1 e 343 IU.mg-1 of protein, respectively. The non-agitated condition showed a greater potential for obtaining proteins, total proteases, caseinolytic and fibrinolytic enzymes, with maximum values of 433 mg.g-1 of extract, 71 U.mL-1 of extract, 63.62 mm2 and 50.27 mm2, respectively. Thus, a medium composed of soy peptone, yest extract and glucose in a 1:2:4 proportion is recommended, under agitation to produce protease inhibitors, and the non-agitated condition when the target is, mainly caseinolytic and fibrinolytic enzymes.

Ganoderma lucidum é um cogumelo medicinal amplamente reconhecido como fonte de biomoléculas com propriedades farmacológicas, entretanto, pouco se conhece acerca dos fatores que influenciam a síntese de proteínas bioativas por esse fungo, quando cultivado sob fermentação submersa. O objetivo deste trabalho foi avaliar a produção de biomassa micelial e de proteases e inibidores de proteases intracelulares por G. lucidum cultivado em diferentes condições de fermentação submersa. O cultivo foi realizado em meio contendo glicose (10 ou 20 g.L-1), peptona de soja (2,5 ou 5 g.L-1) e extrato de levedura (5 g.L-1), com incubação sob agitação (120 rpm) ou não-agitado, totalizando 8 condições experimentais. A produção de biomassa foi determinada a partir do peso seco e o consumo de glicose a partir da quantificação de açúcares redutores. As proteínas foram extraídas em NaCl (0,15 M) e os extratos proteicos foram submetidos à quantificação de proteínas pelo método de Bradford, atividade proteolítica total usando azocaseína, atividade caseinolítica e fibrinolítica em placa de Petri, atividade de inibidores de serino-proteases (tripsina e quimotripsina) e cisteíno-protease (papaína). O cultivo em condição agitada apresentou maior produção de biomassa com valor máximo de 7g.L-1, além de maiores atividades de inibidores de tripsina, quimotripsina e papaína, com 154 UI.mg-1, 153 UI.mg-1 e 343 UI.mg-1 de proteína, respectivamente. A condição não-agitada demonstrou maior potencial para a obtenção de proteínas, proteases totais, enzimas caseinolíticas e fibrinolíticas, com valores máximos de 433 mg.g-1 de extrato, 71 U.mL-1 de extrato, 63,62 mm2 e 50,27 mm2, respectivamente. Assim, recomenda-se o meio composto de peptona de soja, extrato de levedura e glicose na proporção 1:2:4, em condição agitada para a produção de inibidores de proteases, e a condição não-agitada para a síntese de proteases, principalmente enzimas caseinolíticas e fibrinolíticas.

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Trypanosoma is a hemoflagellate capable of infecting a wide variety of invertebrates and vertebrates, such as Neotropical freshwater fish. The present study described and morphologically compared Trypanosoma spp., found in Platydoras armatulus, Valenciennes, 1840, in southwestern Amazon. Fish specimens were sampled in Ipixuna and Juruá rivers located in the states of Amazonas and Acre, Brazil. Fish blood samples were taken by cardiac puncture, and smears were prepared for quantification, morphometric measurements, and morphotyping (characterization of the trypanosomes according to their morphological variations) of trypanosomes found. Prevalence, mean abundance, and intensity of parasitism were estimated in the parasitized fish specimens. Five fish specimens were collected, showing a 100% prevalence of parasites in the host. We found two Trypanosoma morphotypes, A and B, in which A had the highest infection intensity in host specimens. Thus, the present study presented the first report of Trypanosoma parasitizing P. armatulus, with different morphological variations.

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A raça tropicalmente adaptada Curraleiro Pé Duro (CPD) possui grande rusticidade e capacidade de produção. A técnica de criopreservação de células somáticas permite estocar, por tempo indeterminado, o material genético. O objetivo deste trabalho é avaliar a viabilidade de fibroblastos, pós-criopreservação, em protocolos diferentes. Foi utilizada uma biópsia auricular de um bovino CPD, que passou por antissepsia e anestesia local. Posteriormente o material foi processado e incubado para ser observado quanto à confluência e à morfologia. Em seguida, os fibroblastos foram criopreservados em três tratamentos (T1, T2 e T3). Após serem criopreservados, foram descongelados e analisados quanto à viabilidade celular, à capacidade de crescimento e à morfologia. Na análise de variância e das médias, foram comparados pelo teste de Tukey com significância de 5%. Não foram observadas, nos protocolos, diferenças estatísticas entre a viabilidade celular (T1 = 67,98%, T2 = 71,42% e T3 = 69,93%), a capacidade de confluência (T1 = 80%, T2 = 90%, T3 = 85%) ou a passagem de origem das células. A criopreservação de fibroblastos auriculares de bovinos CPD não mostrou diferença entre os três métodos, sugerindo até que o método que demanda equipamentos menos especializados (T1) é tão eficiente quanto os demais.

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