32 research outputs found

    Effect of nicotine on the viability and morphology of fibroblasts: in vitro study

    Get PDF
    O objetivo do estudo foi avaliar in vitro o efeito da nicotina sobre a viabilidade e a morfologia celular utilizando-se uma linhagem contínua de fibroblastos. Para tal, foram formados dois grupos experimentais segundo a dose (0 - controle, 10 mig, 100 mig, 0,5 mg, 1 mg) e o tempo de condicionamento (1 e 24 horas). Cada um dos 12 orifícios de uma placa para cultura celular recebeu 2 ml de meio de Eagle, e 1 ml de suspensão de meio de cultura contendo aproximadamente 1 × 10(5) células/ml. Foi, então, acrescentada a solução de nicotina nas diferentes concentrações. Após o condicionamento com a droga, nos dois períodos testados, as células foram coradas com azul de trypan 0,4%, e observadas em microscópio invertido por um examinador cego para os grupos experimentais, que avaliou a viabilidade e a morfologia segundo o índice de Gamal. Os experimentos foram repetidos 5 vezes. Quanto à morfologia, os resultados obtidos demonstraram, no grupo condicionado por 1 h, que os controles apresentaram diferenças estatisticamente significantes em relação apenas à maior dose de nicotina; no entanto, foram encontradas diferenças estatisticamente significantes entre o controle e todas as concentrações após 24 horas de condicionamento. Na viabilidade celular, um maior número de células não viáveis foi observado nas diferentes concentrações de nicotina em comparação aos controles tanto após 1 quanto 24 horas de condicionamento (p < 0,05). Em ambos períodos existiu uma tendência significativa de aumento do número de células não viáveis com o aumento da dose de nicotina (p = 0,0053; p = 0,00001 após 1 e 24 h respectivamente). Portanto, conclui-se que a nicotina pode alterar, in vitro, a viabilidade e a morfologia de fibroblastos de forma proporcional à dose e ao tempo de exposição.The aim of this study was to evaluate, in vitro, the effect of nicotine on the viability and morphology of fibroblasts from a continuous lineage. Two experimental groups were prepared, with different drug dosages (0 - control, 10 mug, 100 mug, 0.5 mg, 1 mg) and conditioning time (1 and 24 hours). Twelve-well microplates were utilized. Each well received 2 ml of fresh culture medium and 1 ml of a solution containing 1 × 10(5) cells/ml. Nicotine was then added to the wells, at the tested concentrations. After the incubation period, cell viability was assessed by means of 0.4% trypan blue staining. Cell viability and morphology were assessed in an inverted microscope, by a single examiner, who was blind as to the experimental groups. The experiment was repeated 5 times. Regarding morphology, in the 1-hour conditioned group there was statistically significant difference between the control group and the group with the greatest dose of nicotine. These differences were also observed between the control group and all nicotine groups after 24 hours. The results of the Kruskal-Wallis test revealed that more unviable cells were found in the groups exposed to nicotine, in comparison with the control group, both after 1 and 24 hours of conditioning (p < 0.05). Moreover, with increasing doses of nicotine there was a directly proportional increase in the number of unviable cells, both after 1 and 24 hours of exposure (p = 0.0053 and p = 0.00001, respectively). The conclusion of this study is that nicotine can alter, in vitro, the viability and morphology of fibroblasts in a manner proportional to the dose and time of exposure

    Relatório de estágio profissional

    Get PDF
    Este trabalho encontra-se estruturado em quatro capítulos. Inicialmente será abordada a importância da elaboração do relatório, a metodologia utilizada, a caracterização do Jardim-Escola, assim como do meio em que se insere e a pertinência deste relatório. O primeiro capítulo é composto pelos relatos diários que refletem os momentos mais pertinentes dos dias de estágio, nas várias turmas. Após cada relato diário seguem- -se as inferências, em que são mencionados pontos de vista pessoais ou explicações que permitam uma melhor compreensão dos relatos antecedidos. Como conclusão, de cada dia mencionado, fundamentar-se-á os temas e metodologias vividas em sala de aula. No segundo capítulo dá-se relevância à planificação de aulas dadas durante o estágio, especificamente em cada área e domínio curricular: Conhecimento do Mundo, Matemática (pré-escolar), Linguagem oral e abordagem à escrita, Língua Portuguesa, Matemática (1.º Ciclo) e Estudo do Meio. Em seguida serão igualmente abordadas as planificações elaboradas para a Prova Prática de Avaliação da Capacidade Profissional. Cada fundamentação será devidamente fundamentada. O terceiro capítulo explorará a avaliação, introduzindo seis dispositivos de avaliação elaborados para as várias áreas curriculares. O quarto capítulo é constituído por uma reflexão final sobre este relatório, em que serão apresentadas algumas limitações, bem como sugestões para novas pesquisas

    MAMMALS IN PORTUGAL : A data set of terrestrial, volant, and marine mammal occurrences in P ortugal

    Get PDF
    Mammals are threatened worldwide, with 26% of all species being includedin the IUCN threatened categories. This overall pattern is primarily associatedwith habitat loss or degradation, and human persecution for terrestrial mam-mals, and pollution, open net fishing, climate change, and prey depletion formarine mammals. Mammals play a key role in maintaining ecosystems func-tionality and resilience, and therefore information on their distribution is cru-cial to delineate and support conservation actions. MAMMALS INPORTUGAL is a publicly available data set compiling unpublishedgeoreferenced occurrence records of 92 terrestrial, volant, and marine mam-mals in mainland Portugal and archipelagos of the Azores and Madeira thatincludes 105,026 data entries between 1873 and 2021 (72% of the data occur-ring in 2000 and 2021). The methods used to collect the data were: live obser-vations/captures (43%), sign surveys (35%), camera trapping (16%),bioacoustics surveys (4%) and radiotracking, and inquiries that represent lessthan 1% of the records. The data set includes 13 types of records: (1) burrowsjsoil moundsjtunnel, (2) capture, (3) colony, (4) dead animaljhairjskullsjjaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8),observation in shelters, (9) photo trappingjvideo, (10) predators dietjpelletsjpine cones/nuts, (11) scatjtrackjditch, (12) telemetry and (13) vocalizationjecholocation. The spatial uncertainty of most records ranges between 0 and100 m (76%). Rodentia (n=31,573) has the highest number of records followedby Chiroptera (n=18,857), Carnivora (n=18,594), Lagomorpha (n=17,496),Cetartiodactyla (n=11,568) and Eulipotyphla (n=7008). The data setincludes records of species classified by the IUCN as threatened(e.g.,Oryctolagus cuniculus[n=12,159],Monachus monachus[n=1,512],andLynx pardinus[n=197]). We believe that this data set may stimulate thepublication of other European countries data sets that would certainly contrib-ute to ecology and conservation-related research, and therefore assisting onthe development of more accurate and tailored conservation managementstrategies for each species. There are no copyright restrictions; please cite thisdata paper when the data are used in publications.info:eu-repo/semantics/publishedVersio

    Mammals in Portugal: a data set of terrestrial, volant, and marine mammal occurrences in Portugal

    Get PDF
    Mammals are threatened worldwide, with ~26% of all species being included in the IUCN threatened categories. This overall pattern is primarily associated with habitat loss or degradation, and human persecution for terrestrial mammals, and pollution, open net fishing, climate change, and prey depletion for marine mammals. Mammals play a key role in maintaining ecosystems functionality and resilience, and therefore information on their distribution is crucial to delineate and support conservation actions. MAMMALS IN PORTUGAL is a publicly available data set compiling unpublished georeferenced occurrence records of 92 terrestrial, volant, and marine mammals in mainland Portugal and archipelagos of the Azores and Madeira that includes 105,026 data entries between 1873 and 2021 (72% of the data occurring in 2000 and 2021). The methods used to collect the data were: live observations/captures (43%), sign surveys (35%), camera trapping (16%), bioacoustics surveys (4%) and radiotracking, and inquiries that represent less than 1% of the records. The data set includes 13 types of records: (1) burrows | soil mounds | tunnel, (2) capture, (3) colony, (4) dead animal | hair | skulls | jaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8), observation in shelters, (9) photo trapping | video, (10) predators diet | pellets | pine cones/nuts, (11) scat | track | ditch, (12) telemetry and (13) vocalization | echolocation. The spatial uncertainty of most records ranges between 0 and 100 m (76%). Rodentia (n =31,573) has the highest number of records followed by Chiroptera (n = 18,857), Carnivora (n = 18,594), Lagomorpha (n = 17,496), Cetartiodactyla (n = 11,568) and Eulipotyphla (n = 7008). The data set includes records of species classified by the IUCN as threatened (e.g., Oryctolagus cuniculus [n = 12,159], Monachus monachus [n = 1,512], and Lynx pardinus [n = 197]). We believe that this data set may stimulate the publication of other European countries data sets that would certainly contribute to ecology and conservation-related research, and therefore assisting on the development of more accurate and tailored conservation management strategies for each species. There are no copyright restrictions; please cite this data paper when the data are used in publications

    Hormonal imbalances of the menstrual cycle and the subgingival microflora

    No full text

    Effects of basic fibroblast growth factor on density and morphology of fibroblasts grown on root surfaces with or without conditioning with tetracycline or EDTA.

    No full text
    A study was conducted to evaluate in vitro the effect of root surface conditioning with basic fibroblast growth factor (b-FGF) on morphology and proliferation of fibroblasts. Three experimental groups were used: non-treated, and treated with 50 microg or 125 microg b-FGF/ml. The dentin samples in each group were divided into subgroups according to the chemical treatment received before application of b-FGF: none, or conditioned with tetracycline-HCl or EDTA. After contact with b-FGF for 5 min, the samples were incubated for 24 h with 1 ml of culture medium containing 1 x 10(5) cells/ml plus 1 ml of culture medium alone. The samples were then subjected to routine preparation for SEM, and random fields were photographed. Three calibrated and blind examiners performed the assessment of morphology and density according to two index systems. Classification and regression trees indicated that the root surfaces treated with 125 microg b-FGF and previously conditioned with tetracycline-HCl or EDTA presented a morphology more suggestive of cellular adhesion and viability (P = 0.004). The density of fibroblasts on samples previously conditioned with EDTA, regardless of treatment with b-FGF, was significantly higher than in the other groups (P < 0.001). The present findings suggest that topical application of b-FGF has a positive influence on both the density and morphology of fibroblasts

    Effect of air-powder system on titanium surface on fibroblast adhesion and morphology.

    No full text
    PURPOSE: To evaluate the number and morphology of fibroblasts grown on machined titanium healing abutments treated with an airpowder system. MATERIALS AND METHODS: Twenty-six abutments were assigned to two experimental groups: control (no treatment) and treated (exposed to the Prophy-Jet for 30 seconds). The specimens were incubated for 24 hours with fibroblastic cells in multiwell plates, followed by routine laboratory processing for scanning electron microscope analysis. The specimens were photographed at x 350, and the cell number was counted on an area of approximately 200 um2. RESULTS: No significant differences were found on morphology between the groups (P > 0.05); however, the control group presented a significantly greater amount of cells (71.44 +/- 31.93, mean +/- SD) in comparison with treated group (35.31 +/- 28.14), as indicated by a nonpaired t test (P = 0.001). CONCLUSION: The use of an air-abrasive prophylaxis system on the surface of titanium healing abutments reduced the cells proliferation but did not influence cell morphology

    Periodontal conditions of teeth presenting pathologic migration.

    No full text
    The aim of the present study was to evaluate the periodontal conditions of anterior teeth that presented pathologic migration in patients with chronic periodontitis and to compare periodontal destruction in migrated versus non-migrated teeth. The sample included 32 patients of both sexes (mean age: 46.0 +/- 11.6 years) diagnosed with generalized chronic periodontitis and selected on the basis of the presence of pathologic migration in one or more anterior teeth. This migration was classified according to the following categories: facial flaring, diastema, proximal tilting, rotation or extrusion. The periodontal parameters recorded were clinical attachment loss (CAL) and percentage of radiographic bone loss (BL). Mean CAL of 5.50 +/- 2.20 mm and mean BL of 41.90 +/- 15.40% were found in 115 teeth assessed. The most frequent type of migration was facial flaring (34.80%), followed by diastema (27.00%). Extrusion was hardly observed in the sample (4.30%). However, greater severity of BL and CAL were observed in teeth with this type of migration (59.44% and 8.42 mm, respectively), and in teeth with facial flaring (45.17% of BL and 6.07 mm of CAL). Kruskal-Wallis test indicated that BL presented by teeth with extrusion or facial flaring was greater than that observed in rotated or tilted teeth (p < 0.05), while there was no difference between groups regarding CAL (p = 0.11). It was observed that anterior teeth with pathologic migration presented greater CAL and BL (5.1 mm and 40%) than non-migrated teeth (4.1 and 31%). The study indicated that the most prevalent kind of pathologic migration is facial flaring, which was associated to higher level of bone loss

    p38 MAPK regulates IL-1β induced IL-6 expression through mRNA stability in osteoblasts

    No full text
    Osteoblast-derived IL-6 functions in coupled bone turnover by supporting osteoclastogenesis favoring bone resorption instead of bone deposition. Gene regulation of IL-6 is complex occurring both at transcription and post-transcription levels. The focus of this paper is at the level of mRNA stability, which is important in IL-6 gene regulation. Using the MC3T3-E1 as an osteoblastic model, IL-6 secretion was dose dependently decreased by SB203580, a p38 MAPK inhibitor. Steady state IL-6 mRNA was decreased with SB203580 (2 μM) ca. 85% when stimulated by IL-1β (1-5 ng/ ml). These effects require de novo protein synthesis as they were inhibited by cycloheximide. p38 MAPK had minor effects on proximal IL-6 promoter activity in reporter gene assays. A more significant effect on IL-6 mRNA stability was observed in the presence of SB203580. Western blot analysis confirmed that SB203580 inhibited p38 MAP kinase, in response to IL-1β in a dose dependent manner in MC3T3-E1 cells. Stably transfected MC3T3-E1 reporter cell lines (MC6) containing green fluorescent protein (GFP) with the 3′untranslated region of IL-6 were constructed. Results indicated that IL-1β, TNFα, LPS but not parathyroid hormone (PTH) could increase GFP expression of these reporter cell lines. Endogenous IL-6 and reporter gene eGFP-IL-6 3′UTR mRNA was regulated by p38 in MC6 cells. In addition, transient transfection of IL-6 3′UTR reporter cells with immediate upstream MAP kinase kinase-3 and -6 increased GFP expression compared to mock transfected controls. These results indicate that p38 MAPK regulates IL-1β-stimulated IL-6 at a post transcriptional mechanism and one of the primary targets of IL-6 gene regulation is the 3′UTR of IL-6

    Cytotoxicity of two novel formulations of calcium phosphate cements: A comparative in vitro study

    No full text
    The purpose was to evaluate the cytotoxicity of two novel formulations (alpha and beta) of calcium phosphate cements. Positive control, represented by a commercial hydroxyapatite cement, and negative control were included for comparative purposes. A continuous lineage of fibroblastic cells was used, and the effect of the tested materials on both cell proliferation and viability was assessed by counting cell number on hemocytometer and by the trypan blue exclusion test, respectively. Study design attempted to simulate clinical use by allowing direct and indirect contact of cells and cements. Results were analyzed by the Kruskal-Wallis test and indicated that the beta formulation was extremely cytotoxic (P < 0.001), because this material induced the greatest reduction on cell proliferation and viability. The alpha formulation behaved similarly to the positive control regarding its effect on cell proliferation and viability. Thus, it is concluded that alpha formulation has promise for further evaluation of its behavior in vivo
    corecore