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1.
Braz Oral Res ; 38: e021, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38477807

RESUMO

The present study aimed to evaluate the influence of titanium surface nanotopography on the initial bacterial adhesion process by in vivo and in vitro study models. Titanium disks were produced and characterized according to their surface topography: machined (Ti-M), microtopography (Ti-Micro), and nanotopography (Ti-Nano). For the in vivo study, 18 subjects wore oral acrylic splints containing 2 disks from each group for 24 h (n = 36). After this period, the disks were removed from the splints and evaluated by microbial culture method, scanning electron microscopy (SEM), and qPCR for quantification of Streptococcus oralis, Actinomyces naeslundii, Fusobacterium nucleatum, as well as total bacteria. For the in vitro study, adhesion tests were performed with the species S. oralis and A. naeslundii for 24 h. Data were compared by ANOVA, with Tukey's post-test. Regarding the in vivo study, both the total aerobic and total anaerobic bacteria counts were similar among groups (p > 0.05). In qPCR, there was no difference among groups of bacteria adhered to the disks (p > 0.05), except for A. naeslundii, which was found in lower proportions in the Ti-Nano group (p < 0.05). In the SEM analysis, the groups had a similar bacterial distribution, with a predominance of cocci and few bacilli. In the in vitro study, there was no difference in the adhesion profile for S. oralis and A. naeslundii after 24 h of biofilm formation (p > 0.05). Thus, we conclude that micro- and nanotopography do not affect bacterial adhesion, considering an initial period of biofilm formation.


Assuntos
Aderência Bacteriana , Titânio , Humanos , Fusobacterium nucleatum , Microscopia Eletrônica de Varredura , Projetos de Pesquisa
2.
BMC Med Educ ; 24(1): 97, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287390

RESUMO

BACKGROUND: Physiology is widely recognized as a difficult course, which can potentially increase students' withdrawal and failures rates. Several factors are likely contributing to the difficulties in learning physiology, including inherent features of the discipline as well as aspects related to instructions and/or students' perception. With regards to the later, it is currently unknown how students of exercise physiology think and explain physiology in terms of its cause or consequence (i.e., teleological or mechanistic thinking). Therefore, the aims of the present study were to determine 1) whether undergraduate students' perception of cardiorespiratory physiology during exercise follows a predominant teleological or mechanistic thinking, and 2) whether prior enrollment in physiology courses can influence the predominance of teleological vs. mechanistic thinking. METHODS: The test instrument was an online questionnaire about exercise physiology consisting of nine incomplete sentences about exercise physiology where students had to choose between a teleological or a mechanistic complement. The questionnaire was administered to undergraduate students in the following areas: 1) Movement Sciences (n = 152), 2) Health-related (n = 81) and, 3) Health-unrelated programs (n = 64). Students in Movement Sciences and Health-related programs were also analyzed separately in the following categories: 1) students who previously undertook physiology courses, and 2) students who did not take physiology courses. RESULTS: Overall, all groups presented a percentage of teleological thinking above 58%, which is considerably high. Teleological thinking was significantly higher in health-unrelated programs than health-related and movement sciences programs (76 ± 16% vs. 58 ± 26% vs. 61 ± 25%; P < 0.01). Further, students with prior enrollment in physiology classes presented a significantly lower percentage of teleological thinking than students without physiology classes (59 ± 25% vs. 72 ± 22%, respectively; P < 0.01), but the overall teleological reasoning remained predominant. CONCLUSIONS: These results confirm the hypothesis that undergraduate students tend to present teleological as opposed to mechanistic thinking in exercise physiology. Furthermore, although undergraduate students with prior enrollment in physiology classes presented significantly lower teleological thinking, it remained highly predominant suggesting that teleological thinking is partially independent of the degree of familiarity with this discipline.


Assuntos
Fisiologia , Estudantes , Humanos , Aprendizagem , Resolução de Problemas , Percepção , Fisiologia/educação
3.
Ortho Sci., Orthod. sci. pract ; 17(65): 93-99, 2024. ilus, tab
Artigo em Português | BBO - Odontologia | ID: biblio-1556307

RESUMO

Este estudo objetivou determinar o efeito do armazenamento em longo prazo nas características mecânicas dos elásticos intermaxilares e o período apropriado para substituição no uso clínico. 270 elásticos (135 látex e 135 sintéticos), 3/16" médio, foram submetidos a testes de tração uniaxial com estiramento de 200% até 600% dos seus diâmetros internos. Os elásticos foram divididos nos grupos "Como Recebidos" (CR, n = 15); armazenados em refrigerador por 3 anos (n = 60), e armazenados à temperatura ambiente por 3 anos (n = 60). Os grupos de elásticos armazenados foram subdivididos em 4 subgrupos (n = 15 cada): sem estiramento prévio (SEP); estiramento prévio simulando o ambiente intraoral por 24 horas (EP24h), 48 horas (EP48h) e 72 horas (EP72h). Quanto aos elásticos de látex, as forças expressadas pelo grupo SEP, independente da temperatura de armazenamento, permaneceram similares às forças do grupo CR. Elásticos armazenados em temperatura ambiente de SEP até EP72h perderam aproximadamente 25 gF (p = 0.001), enquanto os refrigerados perderam em média 10 gF (p = 0.05). Sobre os elásticos sintéticos, o grupo SEP, independente da temperatura de armazenamento, ganhou, em média, 50 gF (p = 0.001) em comparação ao grupo CR. Os armazenados em temperatura ambiente, desde SEP até EP72h, perderam em média 30 gF (p = 0.001), enquanto os refrigerados perderam aproximadamente 50 gF (p = 0.001). Concluiu-se que os elásticos ortodônticos armazenados em longo prazo em suas embalagens originais expressam forças maiores do que os elásticos novos, e ao usar clinicamente elásticos armazenados a longo prazo, as substituições podem ser feitas a cada 72 horas sem perda da eficiência mecânica (AU)


This paper aimed to determine the effect of long-term storage on latex and non-latex intermaxillary elastics, and the proper time between substitutions. 270 elastics (135 latex and 135 non-latex elastics), medium force and standard size of 3/16", underwent uniaxial tensile tests with increase from 200% to 600% of their inner diameter. Each type was divided into groups of as received elastics (AR - n = 15), 3 years stored under refrigeration (n=60), and e years stored at room temperature (n=60). The stored groups were divided into 4 subgroups (n = 15): no previous stretching (NPS), pre-stretched si mulating the intraoral environment during 24 hours (PS24h), 48 hours (PS48h), and 72 hours (PS72h). About the elastics of latex, the forces expressed by the NPS at room temperature remained equal to the AR, while the forces of the refrigerated NPS had increased ±70 gF on average (p = 0.001). PS24h to PS72h at room temperature showed loss of ±20 gF (p = 0.001) when compared to the NPS or to AR. Non-latex - NPS, regardless of the temperature of storage, increased forces ± 70gF (p = 0.001) when compared to the AR. Starting at PS24h to PS72h, it was seen an average loss of ± 40gF (p = 0.001) when compared to the NPS. All 3 years stored non-latex elastics forces increased ± 30gF (p = 0.01) when compared to the AR. It was concluded that orthodontic elastics long-term stored in their original packages shows higher average forces than new elastics, and the replacement, when using long-term stored could be every 72 hours (AU)


Assuntos
Aparelhos Ortodônticos , Ortodontia , Ortodontia Corretiva
4.
Braz. oral res. (Online) ; 38: e021, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, BBO - Odontologia | ID: biblio-1550156

RESUMO

Abstract The present study aimed to evaluate the influence of titanium surface nanotopography on the initial bacterial adhesion process by in vivo and in vitro study models. Titanium disks were produced and characterized according to their surface topography: machined (Ti-M), microtopography (Ti-Micro), and nanotopography (Ti-Nano). For the in vivo study, 18 subjects wore oral acrylic splints containing 2 disks from each group for 24 h (n = 36). After this period, the disks were removed from the splints and evaluated by microbial culture method, scanning electron microscopy (SEM), and qPCR for quantification of Streptococcus oralis, Actinomyces naeslundii, Fusobacterium nucleatum, as well as total bacteria. For the in vitro study, adhesion tests were performed with the species S. oralis and A. naeslundii for 24 h. Data were compared by ANOVA, with Tukey's post-test. Regarding the in vivo study, both the total aerobic and total anaerobic bacteria counts were similar among groups (p > 0.05). In qPCR, there was no difference among groups of bacteria adhered to the disks (p > 0.05), except for A. naeslundii, which was found in lower proportions in the Ti-Nano group (p < 0.05). In the SEM analysis, the groups had a similar bacterial distribution, with a predominance of cocci and few bacilli. In the in vitro study, there was no difference in the adhesion profile for S. oralis and A. naeslundii after 24 h of biofilm formation (p > 0.05). Thus, we conclude that micro- and nanotopography do not affect bacterial adhesion, considering an initial period of biofilm formation.

5.
Front Neurol ; 14: 1196585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396775

RESUMO

Background: Anodal transcranial direct current stimulation (tDCS) over the primary motor cortex and cerebellum is gaining prominence in the literature due to its potential to favor learning and motor performance. If administered during motor training, tDCS is capable of increasing the effect of training. Considering the motor impairment presented by children with Autism Spectrum Disorders (ASD), atDCS applied during motor training may contribute to the rehabilitation of these children. However, it is necessary to examine and compare the effects of atDCS over the motor cortex and the cerebellum on the motor skills of children with ASD. This information may benefit future clinical indications of tDCS for rehabilitation of children with ASD. The aim of the proposed study is to determine whether anodal tDCS over the primary motor cortex and cerebellum can enhance the effects of gait training and postural control on motor skills, mobility, functional balance, cortical excitability, cognitive aspects and behavioral aspects in children with ASD. Our hypothesis is the active tDCS combined with motor training will enhance the performance of the participants in comparison to sham tDCS. Methods and design: A randomized, sham-controlled, double-blind clinical trial will be conducted involving 30 children with ASD that will be recruited to receive ten sessions of sham or ten sessions of active anodal tDCS (1 mA, 20 min) over the primary motor cortex or cerebellun combined with motor training. The participants will be assessed before as well as one, four and eight weeks after the interventions. The primary outcome will be gross and fine motor skills. The secondary outcomes will be mobility, functional balance, motor cortical excitability, cognitive aspects and behavioral aspects. Discussion: Although abnormalities in gait and balance are not primary characteristics of ASD, such abnormalities compromise independence and global functioning during the execution of routine activities of childhood. If demonstrated that anodal tDCS administered over areas of the brain involved in motor control, such as the primary motor cortex and cerebellum, can enhance the effects of gait and balance training in only ten sessions in two consecutive weeks, the clinical applicability of this stimulation modality will be expanded as well as more scientifically founded.Clinical trial registration February 16, 2023 (https://ensaiosclinicos.gov.br/rg/RBR-3bskhwf).

6.
Am J Orthod Dentofacial Orthop ; 161(4): e353-e360, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34955363

RESUMO

INTRODUCTION: The objective of this investigation was to evaluate the effects of high-intensity light-emitting diode (LED) light from a curing device on the retinas of Wistar rats. METHODS: Six male Wistar rats were used, and their ocular structures were the focus of this study. During the photostimulation of each animal, the right eye of the animal, considered the control sample, was covered with a removable polyvinyl chloride cap, and the contralateral eye, the experimental sample, was exposed to high-intensity LED light, 3200 mW/cm2 (VALO Ortho; Ultradent Products, South Jordan, Utah) for 144 seconds from a distance of 30 cm. The animals were exposed to the LED light 3 times on the same day to investigate if any acute inflammatory changes in the retina occurred. Seven days after the photostimulation sessions, the animals were anesthetized and perfused with paraformaldehyde solution. After which, the eyes were resected and processed histologically. The histologic sections were analyzed stereologically and histomorphometrically to measure the parameters of the retina under investigation. RESULTS: There was a statistically significant increase in total retinal volume in the experimental group because of the increased volume of the ganglion cell layers, inner plexiform layers, outer nuclear layers, and the cone and rod extensions. There was no statistically significant difference in terms of density. However, there was a statistically significant increase in the nuclear area of the cells in all the studied layers in the group exposed to high-intensity LED light. In addition, hyperchromatic cells that are suggestive of pyknosis were observed. CONCLUSIONS: An acute but short protocol of exposure of high-intensity LED light to the eye caused morphometric alterations in the retinal structures, specifically in the nuclear area of the photosensitive cells.


Assuntos
Luz , Retina , Animais , Modelos Animais de Doenças , Humanos , Jordânia , Masculino , Ratos , Ratos Wistar , Retina/patologia
7.
J Ethnopharmacol ; 284: 114778, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34715299

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Coffea arabica is commonly known for its cardiotonic and neurotonic activities, but in some places' folk medicine, like in Arabia and Africa, C. arabica is used to treat headache, migraine, the flu, anemia, oedema, asthenia, asthma, inflammation and wounds. AIMS OF THE STUDY: The aims were to evaluate if the aqueous extracts of Coffea arabica, prepared from beans with different degrees of roasting, and their main chemical constituents could exert an in vivo anti-gouty effect. MATERIALS AND METHODS: Coffea extracts were obtained from the beans of not roasted, light, medium and dark roasted coffee and from decaffeinated and traditional coffees and were prepared with water at 25°C and at 98°C. C57BL/6 mice were induced to gout by an injection of monosodium urate crystals and treated with coffee extracts at doses of 25, 75 and 225 mg/kg and their chemical constituents at a dose of 10 mg/kg. The antinociceptive and anti-inflammatory effects were evaluated. RESULTS: Treatments with Coffea extracts prepared with water at 98°C were more effective to exert antinociceptive and anti-inflammatory activities than the ones prepared with water at 25°C. Caffeic and chlorogenic acids reduced hypernociception in animals when compared with negative control group (7.79 and 5.69 vs 18.53; P < 0.05 and P < 0.001, respectively), inhibited neutrophil migration (1.59 × 104 and 0.38 × 104 vs 9.47 × 104; P < 0.0001 both) and decreased pro-inflammatory cytokines concentration (IL-1ß, IL-6 and TNF-α). CONCLUSIONS: We have demonstrated that our treatments attenuated gout, and this effect could be attributed to a reducement in hypernociception, neutrophil migration and cytokines concentration. These results suggest coffee as a potential candidate for studies in acute gout therapy.


Assuntos
Coffea/química , Gota/tratamento farmacológico , Inflamação/tratamento farmacológico , Dor/tratamento farmacológico , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Analgésicos/química , Analgésicos/farmacologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fitoterapia , Distribuição Aleatória
8.
J Ethnopharmacol ; 280: 114460, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34324952

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ethanolic extract of aerial parts from Lychnophora pinaster Mart. are used in traditional Brazilian medicine for treating pain, rheumatism and inflammation. AIM OF THE STUDY: Drugs for the treatment of gout present severe adverse effects, justifying the need to search for new therapeutic options. The aim of the present study was to evaluate the effects of the ethanolic extract of L. pinaster and its main constituents in arthritis induced in mice by the injection of monosodium urate (MSU) crystals. MATERIALS AND METHODS: Antinociceptive effect was investigated using an electronic pressure-meter nociception paw test in C57BL/6 mice. Anti-gouty arthritis was investigated in mice induced with gout by the injection of MSU crystals into their femur-tibial tissue. Ethanolic extract of the aerial parts of Lychnophora pinaster and its main chemical constituents were evaluated as treatment. RESULTS: The ethanolic extract and their main chemical constituents inhibited neutrophil migration, reduced IL-1ß and TNF-α concentrations in the inflamed tissue and showed antinociceptive activity. CONCLUSIONS: Gouty arthritis effects of the ethanolic extract can be attached to a synergistic effect of terpenes, flavonoids and phenolic acids present in the extract. Results obtained support the use of this extract and its main chemical constituents in the treatment of gout, inflammation, and pain.


Assuntos
Artrite Gotosa/tratamento farmacológico , Asteraceae/química , Gota/tratamento farmacológico , Extratos Vegetais/farmacologia , Analgésicos/química , Analgésicos/isolamento & purificação , Analgésicos/farmacologia , Animais , Artrite Gotosa/patologia , Brasil , Modelos Animais de Doenças , Gota/patologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dor/tratamento farmacológico , Dor/etiologia , Extratos Vegetais/química
9.
J Ethnopharmacol ; 269: 113738, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33359866

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Lychnophora trichocarpha and Lychnophora passerina are species used in folk medicine to treat inflammation, pain, and rheumatism. Previous studies have demonstrated the anti-inflammatory effect of ethanol extracts of these species and identified that sesquiterpene lactones contribute to this activity. AIM OF THE STUDY: Gout is an acute inflammatory arthritis caused by the deposition of monosodium urate (MSU) crystals in joints. Inflammation in joints induces oxidative stress in defense cells, releasing pro-inflammatory mediators. This study has three objectives: (1) to demonstrate the effects of sesquiterpene lactones lychnopholide and eremantholide C isolated from L. trichocarpha and goyazensolide isolated from L. passerina on arthritis induced by MSU crystals in C57BL6 mice; (2) to determine whether or not these compounds can inhibit the migration of neutrophils and the release of TNF-α and IL-1ß cytokines in the inflammation region; and (3) to evaluate the effects of sesquiterpene lactones on the activities of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in the cartilage of C57BL/6 mice with gouty arthritis. MATERIALS AND METHODS: The anti-inflammatory, antinociceptive, and antioxidant activities of sesquiterpene lactones in C57BL/6 mice with MSU crystal-induced arthritis were evaluated. In our experimental model, the mice were injected with MSU crystals in the tibiofemoral joint to induce arthritis and then treated with indomethacin, vitamin C, and sesquiterpene lactones. Nociception was evaluated before and after inflammation induction and treatments, neutrophil migration, IL-1ß and TNF-α concentrations, and SOD and CAT activities. RESULTS: Sesquiterpene lactones exerted an anti-inflammatory effect by inhibiting neutrophil migration and TNF-α production. These compounds also demonstrated antinociceptive and antioxidant activities. CONCLUSION: Lychnopholide, eremantholide C, and goyazensolide improved the inflammation induced by MSU crystals by inhibiting the migration of neutrophils to the inflamed area and by blocking the release of the pro-inflammatory cytokine TNF-α. In addition, sesquiterpene lactones reduced oxidative stress by activating SOD and CAT. These results suggest that sesquiterpene lactones have anti-gout activity through the inflammation, pain, and oxidative stress pathways.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Artrite Gotosa/tratamento farmacológico , Asteraceae/química , Lactonas/farmacologia , Sesquiterpenos/farmacologia , Analgésicos/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Artrite Gotosa/induzido quimicamente , Hidrocarbonetos Aromáticos com Pontes/isolamento & purificação , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Catalase/metabolismo , Furanos/isolamento & purificação , Furanos/farmacologia , Furanos/uso terapêutico , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Interleucina-1beta/metabolismo , Articulações/efeitos dos fármacos , Lactonas/isolamento & purificação , Lactonas/uso terapêutico , Masculino , Medicina Tradicional/métodos , Camundongos Endogâmicos C57BL , Neutrófilos/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/uso terapêutico , Sesterterpenos/isolamento & purificação , Sesterterpenos/farmacologia , Sesterterpenos/uso terapêutico , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ácido Úrico/toxicidade
10.
J Ethnopharmacol ; 242: 112040, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31252094

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Lychnophora pinaster, known as "Brazilian arnica" is used in folk medicine as alcoholic extract to treat inflammation, pain, rheumatism and bruises. AIM OF THE STUDY: Evaluate the effects of the Lychnophora pinaster's ethanolic extract and its chemical constituents on inflammation and hyperuricemia. MATERIALS AND METHODS: Ethanolic and hexanic extracts were obtained from the aerial parts of L. pinaster. Sesquiterpene E-lychnophoric acid was isolated from hexanic extract and identified by RMN, GC/MS and IR. In vivo anti-hyperuricemic and anti-inflammatory effects of the ethanolic extracts from L. pinaster (40, 125, 375 mg/kg), E-lychnophoric acid and other constituents previous isolated from L. pinaster and identified in the ethanolic extract by HPLC/UV/DAD (rutin, quercetin and vitexina flavonoids, caffeic, cinnamic and chlorogenic acids, lupeol and stigmasterol, at dose of 15 mg/kg) were assayed by experimental model of oxonate-induced hyperuricemia in Swiss mice, liver xanthine oxidase (XOD) inhibition and by MSU-induced paw edema in mice. RESULTS: Ethanolic extract and all its components presented anti-hyperuricemic activity by inhibiting the hepatic xanthine oxidase activity. Ethanolic extract and its chemical constituents, except quercetin and vitexin, were able to reduce paw edema size induced by urate crystals. Hypouricemic and anti-inflammatory results obtained for the ethanolic extract (40, 125, 375 mg/kg) and E-lychnophoric acid (15 mg/kg) were similar those obtained for standard drugs, allopurinol (10 mg/kg) and indomethacin (3 mg/kg). CONCLUSION: Ethanolic extract and E-lychnophoric, chlorogenic, cinnamic and caffeic acids, rutin, lupeol and stigmasterol presented anti-inflammatory and anti-hyperuricemic actvities. These compounds are responsible for the activities presented by the ethanolic extract of L. pinaster. Ethanolic extract and its chemical constituents can be considered promising agents in the therapeutic of inflammation, hyperuricemia and gout.


Assuntos
Anti-Inflamatórios/uso terapêutico , Asteraceae , Supressores da Gota/uso terapêutico , Hiperuricemia/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Etanol/química , Supressores da Gota/química , Supressores da Gota/farmacologia , Hexanos/química , Hiperuricemia/sangue , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Camundongos , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Componentes Aéreos da Planta , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Solventes/química , Ácido Úrico/sangue , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/metabolismo
11.
Phytopathology ; 109(7): 1129-1140, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30794486

RESUMO

Blast, caused by Pyricularia oryzae, has become a devastating disease on wheat in several countries worldwide. Growers need alternative methods for blast management, and silicon (Si) stands out for its potential to decrease the intensity of important diseases in several crops. This study investigated the effect of Si on improving photoassimilate production on flag leaves of wheat plants and their partitioning to spikes in a scenario where blast symptoms decreased as a result of potentiation of defense mechanisms by Si. Wheat plants (cultivar BRS Guamirim) were grown in hydroponic culture with 0 or 2 mM Si and inoculated with P. oryzae at 10 days after anthesis. The Si concentration on flag leaves and spikes of Si-supplied plants increased and resulted in lower blast symptoms. High concentrations of total soluble phenols and lignin-thioglycolic acid derivatives and greater peroxidase, polyphenoloxidase, phenylalanine ammonia-lyase, ß-1,3-glucanase, and chitinase activity occurred on flag leaves and spikes of Si-supplied plants and increased their resistance to blast. The concentration of photosynthetic pigments decreased and the photosynthetic performance of infected flag leaves and spikes from plants not supplied with Si was impaired for chlorophyll a fluorescence parameters including maximal photosystem II quantum efficiency, fraction of energy absorbed used in photochemistry, quantum yield of nonregulated energy dissipation, and quantum yield of regulated energy dissipation. The concentration of soluble sugars was lower on infected flag leaves and spikes from plants not supplied with Si, whereas the hexose-to-sucrose ratio increased on infected flag leaves. Sucrose-phosphate synthase activity was lower and acid invertase activity was higher on flag leaves and spikes of plants not supplied with Si, respectively, compared with Si-supplied plants. The starch concentration on spikes of Si-supplied plants increased. In conclusion, Si showed a beneficial effect in improving the source-sink relationship of infected flag leaves and spikes by preserving alterations in assimilate production and partitioning during the grain filling process.


Assuntos
Ascomicetos , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Silício/farmacologia , Triticum , Clorofila A , Fotossíntese , Triticum/efeitos dos fármacos , Triticum/microbiologia
12.
Natal; s.n; 20180000. 53 p. tab, ilus, graf.
Tese em Português | BBO - Odontologia | ID: biblio-1437581

RESUMO

Introdução: A evolução dos fotopolimerizadores quanto à sua potência e consequente redução do tempo clínico tem se mostrado de grande valia para a otimização da rotina de colagem de bráquetes ortodônticos. Contudo, existe uma carência na literatura do efeito desses aparelhos sobre a retina do profissional e/ou do paciente, uma vez que ambos podem receber indiretamente parte da luz refletida durante os procedimentos clínicos. Objetivo: Avaliar os efeitos do uso de um aparelho fotopolimerizador LED de alta potência nas retinas de ratos Wistar. Material e métodos: Seis ratos Wistar foram utilizados na pesquisa e suas estruturas oculares foram os objetos de estudo. Durante a fotoestimulação de cada animal, o olho direito do animal, considerado a amostra controle, foi coberto com um tampão removível em PVC, enquanto que o olho contralateral, a amostra experimental, foi exposto à luz do LED de alta potência, 3200mW/cm2 (Valo Ortho - Ultradent), por 144 segundos à distância de 30cm. Os animais foram expostos ao LED três vezes durante um dia, com o objetivo de induzir possíveis alterações inflamatórias agudas na retina. Decorrido o período de sete dias após a fotoestimulação, os animais foram anestesiados, procedido à eutanásia, removidos os olhos e processados histologicamente. Em seguida, as lâminas foram digitalizadas utilizando-se uma câmera acoplada a um microscópio óptico e suas imagens analisadas estereologicamente e histomorfometricamente para aferição de parâmetros estudados da retina. Resultados: Houve um aumento estatisticamente significativo no volume total da retina e no volume das camadas de células ganglionares (CCG), camada plexiforme interna (CPI), camada nuclear externa (CNE) e os prolongamentos de cones e bastonetes (PCB) no grupo experimental. Em relação à densidade, não houve diferença estatisticamente significativa. Entretanto, observou-se um aumento estatisticamente significativo da área nuclear das células em todas as camadas estudadas no grupo exposto à luz LED de alta potência. Além disso, observou-se células hipercromadas que são sugestivas de picnose. Conclusões: Mesmo com um protocolo agudo e curto de exposição do olho à luz LED de alta potência, houve uma alteração nas estruturas retinianas, especialmente da atividade metabólica das células fotossensíveis e neuronais, o que ressalta a necessidade de proteção durante a utilização desses aparelhos fotoativadores (AU).


Introduction: The evolution of light curing units (LCU) in terms of potency and consequent reduction of clinical time have been shown to be of great value to orthodontists, regarding the routine of brackets bonding. However, there is a lack in the literature regarding the effect of these devices on the operator and/or patient retina, as both may receive indirect reflected light during procedures. Aims: Evaluate the effect of the use of a high potency light emitting diodebased device (LED) in the retina of Wistar rats. Material and Methods: Six Wistar rats were used and their ocular structures considered objects of the study. During the photostimulation of each animal, the right eye, established as the control sample, was covered with a removable PVC tampon, as the contralateral eye - experimental sample - was exposed to high potency LED light, 3200mW/cm2 (Valo Ortho - Ultradent) for 144 seconds, at the distance of 30cm. Animals were exposed to LED light three times per day, aiming to induce possible acute inflammatory alterations in retina. Seven days after the first photostimulation, all rats were anesthetized and then euthanized for posterior eye removal and histological processing. The histological slides were scanned using a camera connected to an optical microscope and their images analyzed for the measurement of histomorphological and stereological parameters of the retina. Results: A statistically significant raise was found in the total volume of retina and in the following layers: ganglion cells layer (GCL), outer nuclear layer (ONL), inner nuclear layer (INL) and extension of cone and rods (ECR) in the experimental group. Regarding density, no statistically significant difference was observed. However, the nuclear area of the cells raised significantly in all layers analyzed after high potency LED exposure. Besides that, hyperchromic cells suggestive of pyknosis were found. Conclusions: Despite the short and acute protocol of eye exposure to high potency LED, a significant alteration was found, especially in the metabolic activity of photosensitive and neuronal cells. These results emphasize the importance of using eye protection during the use of these devices (AU).


Assuntos
Animais , Ratos , Retina , Altas Potências , Lâmpadas de Polimerização Dentária , Ratos Wistar
13.
Dental press j. orthod. (Impr.) ; 22(6): 61-67, Nov.-Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-891107

RESUMO

ABSTRACT Objective: Evaluate changes in the force system of T-Loop Springs (TLS) preactivated by curvature, due to stress relaxation. Methods: Ninety TLSs measuring 6 x 10 mm, produced out with 0.017 x 0.025-in TMA® wire and preactived by gradual curvature, were randomly distributed into nine groups according to time point of evaluation. Group 1 was tested immediately after spring preactivation and stress relief, by trial activation. The other eight groups were tested after 24, 48 and 72 hours, 1, 2, 4, 8 and 12 weeks, respectively. Using a moment transducer coupled to a digital extensometer indicator adapted to a universal testing machine, the amount of horizontal force, moment and moment-to-force ratios were recorded at every 0.5 mm of deactivation from 5 mm of the initial activation, in an interbracket distance of 23 mm. Results: The horizontal forces decreased gradually among the groups (p< 0.001) and the moments showed a significant and slow decrease over time among the groups (p< 0.001). All groups produced similar M/F ratios (p= 0.532), with no influence of time. Conclusions: The TLSs preactivated by curvature suffered a gradual deformation over time, which affected the force system, specifically the moments, which affected the horizontal forces produced.


RESUMO Objetivo: avaliar as mudanças no sistema de forças das molas T pré-ativadas por curvatura, devido ao alívio de tensão estrutural. Métodos: noventa molas em forma de "T", medindo 6 mm x 10 mm, confeccionadas com fio de beta-titânio TMA® de 0,017" x 0,025" e pré-ativadas por curvatura gradual, foram distribuídas aleatoriamente em nove grupos, de acordo com o momento de avaliação. O Grupo 1 foi testado imediatamente após a pré-ativação da mola e liberação do estresse, por meio de simulação da ativação. Os outros oito grupos foram divididos conforme o intervalo de tempo testado: após 24, 48 e 72 horas; 1, 2, 4, 8 e 12 semanas. Usando um transdutor de momentos acoplado a um indicador digital para extensometria e adaptado a uma máquina universal de ensaios, as magnitudes da força horizontal, do momento e da proporção momento/força (M/F) foram registradas a cada 0,5 mm de desativação a partir da ativação inicial de 5 mm, utilizando-se uma distância interbraquetes de 23 mm. Resultados: as forças horizontais reduziram-se gradualmente nos grupos (p< 0,001) e o momento apresentou uma queda lenta e significativa ao longo do tempo (p< 0,001). Todos os grupos tiveram proporções M/F semelhantes (p= 0,532), não influenciadas pelo período de tempo. Conclusões: as molas pré-ativadas por curvatura gradual sofreram deformação progressiva ao longo do tempo, o que afetou o sistema de forças - especificamente o momento -, alterando as forças horizontais produzidas.


Assuntos
Fios Ortodônticos , Titânio/química , Desenho de Aparelho Ortodôntico , Fechamento de Espaço Ortodôntico/instrumentação , Ligas Dentárias/química , Análise do Estresse Dentário , Estresse Mecânico , Fatores de Tempo , Fenômenos Biomecânicos , Teste de Materiais , Distribuição Aleatória , Estatísticas não Paramétricas
14.
J Ethnopharmacol ; 201: 17-25, 2017 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-28254483

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Campomanesia velutina leaves and branches infusions are used in Brazilian folk medicine to treat diarrhea and to ameliorate intestinal cramps, respectively. AIM OF THE STUDY: Carry out the acute and sub chronic pre-clinical evaluation and thus assess the safety and toxicological potential of the specie. MATERIALS AND METHODS: In vivo toxicity was evaluated by acute and sub chronic toxicity assays conducted according to the guidelines of the Brazilian Agency of National Health Surveillance (Agência Nacional de Vigilância Sanitária - ANVISA). For acute toxicity evaluation, a single dose of aqueous extracts from the leaves (AEL) and branches (AEB) of Campomanesia velutina were orally administered to mice at doses of 300, 600 and 1200mg/kg. Then, the animals were observed for 14 days. In the sub chronic study, the extracts were orally administered to mice for 14 days at doses of 300, 600 and 1200mg/kg. To assess the toxicological effects, animals were closely observed on general behavior, clinical signs of toxicity, body weight, food and water intake. At the end of the experiment, it was performed biochemical and hematological evaluations, as well as histopathological analysis from the following organs: brain, heart, lungs, liver, stomach, small intestine (section) and left kidney. Preliminary phytochemical analysis was performed using thin layer chromatography (TLC) and colorimetric pharmacognostic tests. RESULTS: In oral acute assay, treatment with AEB at the major dose (1200mg/kg) caused diarrhea, abdominal cramps and tremors in females. These effects were reversed at 4th hour. Normochromic normocytic anemia was observed in males treated with AEL 300mg/kg and AEB 600 and 1200mg/kg as well as in females treated with AEB 300 and 1200mg/kg. The kidney of all treated animals showed moderate inflammation and a few hemorrhagic points. In sub chronic assay, treatment with AEL 600mg/kg, AEL 1200mg/kg and AEB 1200mg/kg caused hyper excitability in females that was not reversed. Treatments also had impact on weight gain and the relative weight of males' brain was increased on group treated with AEL 300mg/kg, AEB 300 and AEB 1200mg/kg. Although changes in hematological parameters were not observed, serum creatinine levels were significantly higher in males treated with AEB 300mg/kg. Besides, the heart of all treated animals showed intense hyperemia. Preliminary phytochemical analysis revealed the presence of flavonoids, tannins and phenolic compounds. CONCLUSIONS: Toxicity signs were mainly observed after treatment with AEL and AEB at the two highest tested doses (600 and 1200mg/kg), suggesting that the extracts are relatively safe at its effective dose (300mg/kg). However, alterations on hematological and biochemical parameters and on the kidney and heart of the animals were not closely related with the dose, implying caution on its use.


Assuntos
Myrtaceae , Extratos Vegetais/toxicidade , Animais , Feminino , Coração/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Camundongos , Folhas de Planta , Caules de Planta , Testes de Toxicidade Aguda , Testes de Toxicidade Subcrônica
15.
Artigo em Inglês | MEDLINE | ID: mdl-29375639

RESUMO

Tabebuia species (Bignoniaceae) have long been used in folk medicine as anti-inflammatory, antirheumatic, antimicrobial, and antitumor. The aim of this study was to investigate if aqueous extract from the leaves (AEL) of Tabebuia roseoalba (Ridl.) Sandwith, Bignoniaceae, and its constituents could be useful to decrease serum uric acid levels and restrain the gout inflammatory process. HPLC analysis identified caffeic acid and chlorogenic acid in AEL. Antihyperuricemic effects and inhibition of liver XOD (xanthine oxidoreductase) by AEL and identified compounds were evaluated in hyperuricemic mice. Anti-inflammatory activity was evaluated on MSU (monosodium urate) crystal-induced paw edema. In addition, AEL antioxidant activity in vitro was evaluated. AEL, caffeic, and chlorogenic acids were able to reduce serum uric acid levels in hyperuricemic mice probably through inhibition of liver xanthine oxidase activity and significantly decreased the paw edema induced by MSU crystals. AEL showed significant antioxidant activity in all evaluated assays. The results show that the AEL of Tabebuia roseoalba can be a promising agent for treatment for gout and inflammatory diseases. We suggest that caffeic and chlorogenic acids may be responsible for the activities demonstrated by the species.

16.
Dental Press J Orthod ; 22(6): 61-67, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29364381

RESUMO

OBJECTIVE: Evaluate changes in the force system of T-Loop Springs (TLS) preactivated by curvature, due to stress relaxation. METHODS: Ninety TLSs measuring 6 x 10 mm, produced out with 0.017 x 0.025-in TMA® wire and preactived by gradual curvature, were randomly distributed into nine groups according to time point of evaluation. Group 1 was tested immediately after spring preactivation and stress relief, by trial activation. The other eight groups were tested after 24, 48 and 72 hours, 1, 2, 4, 8 and 12 weeks, respectively. Using a moment transducer coupled to a digital extensometer indicator adapted to a universal testing machine, the amount of horizontal force, moment and moment-to-force ratios were recorded at every 0.5 mm of deactivation from 5 mm of the initial activation, in an interbracket distance of 23 mm. RESULTS: The horizontal forces decreased gradually among the groups (p< 0.001) and the moments showed a significant and slow decrease over time among the groups (p< 0.001). All groups produced similar M/F ratios (p= 0.532), with no influence of time. CONCLUSIONS: The TLSs preactivated by curvature suffered a gradual deformation over time, which affected the force system, specifically the moments, which affected the horizontal forces produced.


Assuntos
Ligas Dentárias/química , Análise do Estresse Dentário , Desenho de Aparelho Ortodôntico , Fechamento de Espaço Ortodôntico/instrumentação , Fios Ortodônticos , Titânio/química , Fenômenos Biomecânicos , Teste de Materiais , Distribuição Aleatória , Estatísticas não Paramétricas , Estresse Mecânico , Fatores de Tempo
17.
Rev. bras. farmacogn ; 26(6): 720-727, Nov.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-829909

RESUMO

ABSTRACT Gout is a destructive arthritis with a high prevalence worldwide. However, the available therapy is not able to increase life quality in many patients. Campomanesia velutina (Cambess) O. Berg, Myrtaceae, is used in Brazilian folk medicine to treat pain, inflammation and rheumatism. The aim of this study was to evaluate the potential of ethanolic and aqueous extracts from C. velutina leaves to treat hyperuricemia and inflammation in gout arthritis model. Ethanolic extract of leaves and aqueous extract of leaves were in vitro assayed on xanthine oxidase inhibitory effect and in vivo on an experimental model of oxonate-induced hyperuricemia in mice, liver xanthine oxidase inhibition and monosodium urate crystal-induced paw edema model. The extracts at both tested doses (100 and 300 mg/kg) reduced serum urate levels. They were also able to inhibit xanthine oxidase in vitro and in vivo, demonstrating that this might be the mechanism of action underlying the urate-lowering effects. In addition, the extracts showed significant anti-inflammatory activity on monosodium urate crystal-induced paw edema, especially aqueous extract (100 and 300 mg/kg) that reduced edema at all evaluated times. Rutin and myricitrin were identified in ethanolic and in aqueous extracts. In this study, myricitrin was able to reduce serum uric acid levels and inhibit liver xanthine oxidase at the dose of 15 mg/kg. The anti-hyperuricemic activity of rutin has been previously reported. Thus, rutin and myricitrin seem to contribute to the observed effects of ethanolic and aqueous extracts. The results demonstrated the ability of aqueous and ethanolic extracts to lower serum urate levels and to reduce edema induced by monosodium urate crystals. Therefore, they may contribute to the management of gout in the future.

18.
Planta Med ; 82(16): 1395-1402, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27159671

RESUMO

Tabebuia species have several uses in folk medicine, including their use to treat inflammation and rheumatism. The aim of this study was to investigate whether the ethanolic extract of leaves from Tabebuia roseoalba and isolated compounds could be useful to decrease serum uric acid levels and restrain the gout inflammatory process. The compounds α-amyrin, ß-amyrin, sitosterol, and stigmasterol were isolated from the ethanolic extract. Rutin and caffeic acid were identified in the ethanolic extract by HPLC analysis. The anti-hyperuricemic effect, liver xanthine oxidoreductase inhibition, and anti-inflammatory activity of the ethanolic extract and isolated compounds were evaluated on hyperuricemic mice and on paw edema induced by monosodium urate crystals in mice. The ethanolic extract of leaves from T. roseoalba, ß-amyrin, and stigmasterol were able to reduce serum uric acid levels in hyperuricemic mice through inhibition of liver xanthine oxidase activity and significantly decreased the paw edema induced by monosodium urate crystals. The antioxidant activity of the ethanolic extract and its ability to inhibit xanthine oxidase were also evaluated in vitro. The ethanolic extract of leaves from T. roseoalba showed significant antioxidant activity in the three evaluated assays. Results were analyzed using GraphPad Prism 5.01. One-way ANOVA followed by Student's Newman-Keul's test was used to determine the significant differences between groups. The results show that the ethanolic extract of leaves from T. roseoalba, ß-amyrin, and stigmasterol can be promising agents for the treatment for gouty arthritis, hyperuricemia, and inflammation. Stigmasterol, ß-amyrin, and rutin contribute to the observed effects of the ethanolic extract of leaves from T. roseoalba.


Assuntos
Artrite Gotosa/tratamento farmacológico , Hiperuricemia/tratamento farmacológico , Inflamação/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Tabebuia/química , Animais , Anti-Inflamatórios/análise , Antioxidantes/análise , Avaliação Pré-Clínica de Medicamentos , Supressores da Gota/análise , Masculino , Camundongos , Fitoterapia , Extratos Vegetais/química
19.
J Ethnopharmacol ; 180: 37-42, 2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26778678

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Leaves infusion of Pimenta pseudocaryophyllus (Gomes) Landrum is used in Brazilian folk medicine to treat the predisposition to arthritical and gouty affections of the joints, fever and other diseases. A refreshing drink prepared with the specie is also used due to its diuretic, sedative and aphrodisiac actions. AIM OF THE STUDY: The study was undertaken to investigate the mechanisms of anti-hyperuricemic effect and anti-inflammatory activity of P. pseudocaryophyllus extracts. MATERIALS AND METHODS: Anti-hyperuricemic effect was investigated using xanthine oxidase assay and uricosuric studies with rats in which hyperuricemia was induced by potassium oxonate and uric acid. Anti-inflammatory activity was investigated on MSU crystal-induced paw edema model. Ethyl acetate extracts of the leaves (EAL) and branches (EAB), ethanolic extracts of leaves (EEL) and branches (EEB) and aqueous extracts of leaves (AL) and branches (AB) were evaluated. RESULTS: The extracts of P. pseudocaryophyllus evaluated showed expressive results regarding the inhibition of xanthine oxidase enzyme in vitro and they were also able to reduce serum uric acid levels in hyperuricemic rats. The investigation of the mechanism of action, it was found that EAL, EAB, EEB, AB (125 and 250 mg/kg) and AL (250 mg/kg) promoted an increase on the urinary excretion of uric acid and EEL, EEB, AB (125 and 250 mg/kg) and EAB (250 mg/kg) were capable to inhibit liver xanthine oxidase. Treatments with EEL (125 and 250 mg/kg) and EEB (250 mg/kg) were able to reduce edema at 48 th h. EAL and EAB (125 and 250 mg/kg) showed significant anti-inflammatory activity on monosodium urate crystal-induced paw edema model at all evaluated times. CONCLUSIONS: The specie P. pseudocaryophyllus showed remarkable anti-hyperuricemic effects through uricosuric effects and inhibition of xanthine oxidase and therefore can be considered as a promise in the treatment of diseases related to hyperuricemia. Moreover, ethyl acetate extracts had significant anti-inflammatory activity.


Assuntos
Anti-Inflamatórios , Supressores da Gota , Pimenta , Extratos Vegetais , Xantina Oxidase/antagonistas & inibidores , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Gota/sangue , Gota/tratamento farmacológico , Gota/urina , Supressores da Gota/farmacologia , Supressores da Gota/uso terapêutico , Hiperuricemia/sangue , Hiperuricemia/tratamento farmacológico , Hiperuricemia/urina , Masculino , Camundongos , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta , Ratos Wistar , Ácido Úrico/sangue , Ácido Úrico/urina , Xantina Oxidase/metabolismo
20.
Pediatr Hematol Oncol ; 32(5): 322-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26086683

RESUMO

OBJECTIVE: to investigate the associations of oral microbiota, leucocytes count, neutrophil count, platelet counts and hemoglobin level, and the severity of oral mucositis in pediatric patients with acute lymphoblastic leukemia (ALL) receiving chemotherapy. MATERIALS AND METHODS: 71 prospective patients were included. Analyses of oral microbiota and blood sample were conducted on days 14 (D14) and 56 (D56) of the Brazilian GBTLI-99 treatment protocol. Herpes simplex virus (HSV) identification was performed by PCR followed by DNA sequencing analysis. Bacteria and fungi identification was obtained by standard microbiological culture tests. RESULTS: 103 episodes of mucositis occurred, being 65 at D14 and 38 at D56. Most cases positive for herpes viral DNA sequences were identified as HSV-1. At D14, we found a significant association between the severity of mucositis and presence of HSV-1 (p = 0.0347), Candida spp. (p = 0.0078), and low platelet count (p = 0.0064). At D56, we found a significant association between the severity of mucositis and the presence of HSV-1 (p = 0.0317), previous HSV-1 presence on D14 (p < 0.0001) and neutrophil count (p = 0.0211). CLINICAL RELEVANCE: the identification of risk factors for mucositis in children and adolescents may contribute to the development of new strategies for prevention and/or treatment, reducing the complications associated with this condition. CONCLUSIONS: the presence of HSV, platelet count, and Candida spp. presence at D14 of ALL induction treatment is associated with increased severity of mucositis in children and adolescents. At D56 of ALL treatment, mucositis severity was associated with neutrophil count, HSV presence, and previous presence of HSV (at D14).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Candida , Candidíase/epidemiologia , Herpes Simples/epidemiologia , Herpesvirus Humano 1 , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Estomatite/epidemiologia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Brasil/epidemiologia , Candidíase/induzido quimicamente , Criança , Pré-Escolar , Feminino , Herpes Simples/induzido quimicamente , Humanos , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Estudos Prospectivos , Estomatite/induzido quimicamente
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