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1.
bioRxiv ; 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37790555

RESUMO

Reaches are complex movements that are critical for survival, and encompass the control of different aspects such as direction, speed, and endpoint precision. Complex movements have been postulated to be learned and controlled through distributed motor networks, of which the thalamus is a highly connected node. Still, the role of different thalamic circuits in learning and controlling specific aspects of reaches has not been investigated. We report dissociable roles of two distinct thalamic nuclei - the parafascicular (Pf) and ventroanterior/ventrolateral (VAL) nuclei - in the refinement of spatial target reaches in mice. Using 2-photon calcium imaging in a head-fixed joystick task where mice learned to reach to a target in space, we found that glutamatergic neurons in both areas were most active during reaches early in learning. Reach-related activity in both areas decreased late in learning, as movement direction was refined and reaches increased in accuracy. Furthermore, the population dynamics of Pf, but not VAL, covaried in different subspaces in early and late learning, but eventually stabilized in late learning. The neural activity in Pf, but not VAL, encoded the direction of reaches in early but not late learning. Accordingly, bilateral lesions of Pf before, but not after learning, strongly and specifically impaired the refinement of reach direction. VAL lesions did not impact direction refinement, but instead resulted in increased speed and target overshoot. Our findings provide new evidence that the thalamus is a critical motor node in the learning and control of reaching movements, with specific subnuclei controlling distinct aspects of the reach early in learning.

2.
Exp Oncol ; 45(1): 107-119, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37417276

RESUMO

BACKGROUND: Skeletal muscle wasting is a common phenotypic feature of several types of cancer, and it is associated with functional impairment, respiratory complications, and fatigue. However, equivocal evidence remains regarding the impact of cancer-induced muscle wasting on the different fiber types. AIM: The aim of this study was to investigate the impact of urothelial carcinoma induced in mice on the histomorphometric features and collagen deposition in different skeletal muscles. MATERIALS AND METHODS: Thirteen ICR (CD1) male mice were randomly assigned into two groups: exposed to 0.05% N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in drinking water for 12 weeks, plus 8 weeks of tap water (BBN, n = 8) or with access to tap water for 20 weeks (CONT, n = 5). Tibialis anterior, soleus, and diaphragm muscles were collected from all animals. For cross-sectional area and myonuclear domain analysis, muscle sections were stained with hematoxylin and eosin, and for collagen deposition assessment, muscle sections were stained with picrosirius red. RESULTS: All animals from the BBN group developed urothelial preneoplastic and neoplastic lesions, and the tibialis anterior from these animals presented a reduced cross-sectional area (p < 0.001), with a decreased proportion of fibers with a higher cross-sectional area, increased collagen deposition (p = 0.017), and higher myonuclear domain (p = 0.031). BBN mice also showed a higher myonuclear domain in the diaphragm (p = 0.015). CONCLUSION: Urothelial carcinoma induced muscle wasting of the tibialis anterior, expressed by a decreased cross-sectional area, higher infiltration of fibrotic tissue, and increased myonuclear domain, which also increased in the diaphragm, suggesting that fast glycolytic muscle fibers are more susceptible to be affected by cancer development.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Camundongos , Masculino , Animais , Carcinoma de Células de Transição/patologia , Neoplasias da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/patologia , Camundongos Endogâmicos ICR , Músculo Esquelético/patologia , Músculo Esquelético/fisiologia , Fibras Musculares de Contração Rápida/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/patologia
3.
bioRxiv ; 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37214823

RESUMO

The brain can learn to generate actions, such as reaching to a target, using different movement strategies. Understanding how different variables bias which strategies are learned to produce such a reach is important for our understanding of the neural bases of movement. Here we introduce a novel spatial forelimb target task in which perched head-fixed mice learn to reach to a circular target area from a set start position using a joystick. These reaches can be achieved by learning to move into a specific direction or to a specific endpoint location. We find that mice gradually learn to successfully reach the covert target. With time, they refine their initially exploratory complex joystick trajectories into controlled targeted reaches. The execution of these controlled reaches depends on the sensorimotor cortex. Using a probe test with shifting start positions, we show that individual mice learned to use strategies biased to either direction or endpoint-based movements. The degree of endpoint learning bias was correlated with the spatial directional variability with which the workspace was explored early in training. Furthermore, we demonstrate that reinforcement learning model agents exhibit a similar correlation between directional variability during training and learned strategy. These results provide evidence that individual exploratory behavior during training biases the control strategies that mice use to perform forelimb covert target reaches.

4.
Pulmonology ; 27(6): 529-562, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33931378

RESUMO

INTRODUCTION: The COVID-19 pandemic originated in China and within about 4 months affected individuals all over the world. One of the limitations to the management of the COVID-19 is the diagnostic imaging to evaluate lung impairment and the patients' clinical evolution, mainly, in more severe cases that require admission into the intensive care unit. Among image examinations, lung ultrasound (LU) might be a useful tool to employ in the treatment of such patients. METHODS: A survey was carried out on PubMed to locate studies using the descriptors: ((Lung ultrasound OR ultrasound OR lung ultrasonography OR lung US) AND (coronavirus disease-19 OR coronavirus disease OR corona virus OR COVID-19 OR COVID19 OR SARS-CoV-2)). The period covered by the search was November 2019 to October 2020 and the papers selected reported LU in COVID-19. RESULTS: Forty-three studies were selected to produce this systematic review. The main LU findings referred to the presence of focal, multifocal and/or confluent B lines and the presence of pleural irregularities. CONCLUSIONS: The use of LU in the evaluation of patients with COVID-19 should be encouraged due to its intrinsic characteristics; a low cost, radiation free, practical method, with easy to sanitize equipment, which facilitates structural evaluation of lung damage caused by SARS-CoV-2. With the increase in the number of studies and the use of ultrasound scans, LU has been shown as a useful tool to evaluate progression, therapeutic response and follow-up of pulmonary disease in the patients with COVID-19.


Assuntos
COVID-19 , Pulmão , Ultrassonografia , COVID-19/diagnóstico por imagem , Teste para COVID-19 , Progressão da Doença , Humanos , Pulmão/diagnóstico por imagem , Pandemias
5.
Anim Genet ; 52(1): 32-46, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33191532

RESUMO

This study aimed to assess the predictive ability of different machine learning (ML) methods for genomic prediction of reproductive traits in Nellore cattle. The studied traits were age at first calving (AFC), scrotal circumference (SC), early pregnancy (EP) and stayability (STAY). The numbers of genotyped animals and SNP markers available were 2342 and 321 419 (AFC), 4671 and 309 486 (SC), 2681 and 319 619 (STAY) and 3356 and 319 108 (EP). Predictive ability of support vector regression (SVR), Bayesian regularized artificial neural network (BRANN) and random forest (RF) were compared with results obtained using parametric models (genomic best linear unbiased predictor, GBLUP, and Bayesian least absolute shrinkage and selection operator, BLASSO). A 5-fold cross-validation strategy was performed and the average prediction accuracy (ACC) and mean squared errors (MSE) were computed. The ACC was defined as the linear correlation between predicted and observed breeding values for categorical traits (EP and STAY) and as the correlation between predicted and observed adjusted phenotypes divided by the square root of the estimated heritability for continuous traits (AFC and SC). The average ACC varied from low to moderate depending on the trait and model under consideration, ranging between 0.56 and 0.63 (AFC), 0.27 and 0.36 (SC), 0.57 and 0.67 (EP), and 0.52 and 0.62 (STAY). SVR provided slightly better accuracies than the parametric models for all traits, increasing the prediction accuracy for AFC to around 6.3 and 4.8% compared with GBLUP and BLASSO respectively. Likewise, there was an increase of 8.3% for SC, 4.5% for EP and 4.8% for STAY, comparing SVR with both GBLUP and BLASSO. In contrast, the RF and BRANN did not present competitive predictive ability compared with the parametric models. The results indicate that SVR is a suitable method for genome-enabled prediction of reproductive traits in Nellore cattle. Further, the optimal kernel bandwidth parameter in the SVR model was trait-dependent, thus, a fine-tuning for this hyper-parameter in the training phase is crucial.


Assuntos
Bovinos/genética , Aprendizado de Máquina , Modelos Genéticos , Reprodução/genética , Animais , Brasil , Feminino , Genômica , Fenótipo , Polimorfismo de Nucleotídeo Único , Gravidez
6.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1093-1101, July-Aug. 2020. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1131520

RESUMO

A relação da eficiência nutricional com a idade e o peso à puberdade e as características reprodutivas foram estudadas em 35 novilhas F1 Holandês x Gir, em ensaios usando o consumo alimentar residual (CAR) nos períodos pós-desaleitamento (PD) e pós-puberdade (PP). Novilhas PD (P<0,0001) e PP (P<0,001) foram ranqueadas como de alta, intermediária e baixa eficiências e apresentaram CAR de -0,259 -0,014 e 0,346kg/dia e -0,848 -0,096 e 0,842kg/dia, respectivamente. Novilhas PD diferiram (P<0,05) na idade à puberdade entre ranques de alta, intermediária e baixa eficiências, em média, aos 339,7; 346,4; 315,3 dias, respectivamente. Os pesos à puberdade de novilhas PD com alta, intermediária e baixa eficiências foram, em média, de 321±28,1kg e não diferiram (P>0,05) entre CAR. Não foi verificada correlação entre diâmetro folicular, taxa de crescimento do folículo, número de ondas foliculares no ciclo estral e taxa de gestação à primeira IA com o CARPD ou CARPP. Novilhas F1HG selecionadas para CAR com baixa eficiência podem ter idade à puberdade 10 dias a mais, quando comparadas às novilhas de alta eficiência para CAR. Não foi verificado que novilhas selecionadas para alta ou baixa eficiências alimentares, usando CAR, tivessem algum impacto negativo sobre características reprodutivas avaliadas.(AU)


The relationship between nutritional efficiency and age and weight at puberty and reproductive traits was studied in 35 F1 Holstein x Gyr heifers, in trials using residual food consumption (CAR) in the post-weaning (PW) and post-pubertal (PP) periods. PD heifers (P<0.0001) and PP (P<0.001) were classified as high, intermediate and low efficiencies and presented CAR of -0.259 -0.014 and 0.346kg/day and -0.848 -0.096 and 0.842kg/day, respectively. PD heifers differed (P<0.05) in age at puberty between high, intermediate and low efficiencies, on average, at 339.7, 346.4 and 315.3 days, respectively. The weight at puberty of PD heifers with high, intermediate and low efficiencies were, on average, 321±28.1kg and did not differ (P>0.05) between CAR. No correlation was found between follicular diameter, follicle growth rate, number of follicular waves in the estrous cycle and pregnancy rate at 1st AI with the CARPD or CARPP. F1HG heifers selected for CAR with low efficiency can be aged at puberty 10 days longer when compared to high-efficiency heifers for CAR. These results did not show that heifers selected for high or low food efficiency, using CAR, had negative impact on the reproductive characteristics evaluated.(AU)


Assuntos
Animais , Feminino , Bovinos , Fenótipo , Aumento de Peso , Ciclo Estral , Comportamento Alimentar , Pesos e Medidas Corporais/veterinária , Taxa de Gravidez
7.
Med Hypotheses ; 144: 109979, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32570162

RESUMO

Atheromatous plaques occurring in large arteries are common and life-threatening lesions. Multiple factors are involved in the pathogenesis of atheromatous plaques, such as hyperlipidaemia and hypercholesterolaemia, high blood pressure and chronic systemic inflammation. Recent findings have suggested that infection with high-risk human papillomavirus (HPV) may increase the risk of developing atheromatous plaques. However, HPV is considered a tissue-specific virus with a strong tropism towards squamous epithelial cells, and the mechanisms whereby it may promote the development of atheromas remain unclear. Here, we propose a connecting hypothesis to explain the possible causative role of HPV on atheroma development. We hypothesize that HPV infection may promote atheroma formation in infected patients by enhancing systemic inflammation or by directly targeting blood vessels via nucleic acids carried by extracellular vesicles such as exosomes. The pro-inflammatory effects of HPV and the release of extracellular vesicles by HPV-transformed cells are well documented in scientific literature. Possible experimental approaches to test this hypothesis are also discussed, especially experiments employing transgenic mice bearing HPV16 transgenes. If correct, this hypothesis would have major implications for the prevention of cardiovascular diseases, especially due to the preventable nature of HPV infection through vaccination.


Assuntos
Aterosclerose , Infecções por Papillomavirus , Animais , Papillomavirus Humano 16 , Humanos , Camundongos , Camundongos Transgênicos , Infecções por Papillomavirus/complicações , Fatores de Risco
8.
Public Health ; 179: 45-50, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726400

RESUMO

OBJECTIVES: The objective of this study was to estimate mortality risk among women exposed to violence in Brazil using population-based data. STUDY DESIGN: This study used a linked database containing nearly 800,000 violence (against women) notifications and 16,500 associated deaths over the period 2011-2016. METHODS: Aggregate age-standardized population-based rates of mortality were built to estimate risk ratios (RRs) at the national and state level, and for different forms of violence and causes of death, as well as type of offender involved, and across various characteristics of the women. RRs compared the rate of mortality among women exposed to violence with that in the general population of women - excess mortality due to violence was also derived from this comparison. The analysis was divided into two time periods (2011-13 and 2014-16). RESULTS: During 2014-16, women exposed to violence had an estimated mortality risk that was 8.3 [95% confidence interval (CI): 8.2-8.5] times higher than that of the general woman population, and an estimated 100 women died on a weekly basis as a direct or indirect consequence of exposure to violence. Higher (all-cause) mortality risk was associated with physical violence and violence that involved repetition and that was self-inflicted. The risk of mortality increased when the cause of death involved external causes (RR: 51.2, 95% CI: 49.6-52.8). When death was attributable to (i) non-communicable diseases and (ii) communicable, maternal, neonatal, and nutritional diseases, the risk was 5.4 [95% CI: 5.3-5.6] and 6.7 [95% CI: 6.1-7.2] times, respectively. Women at greatest (all-cause) mortality risk include white and multiracial (parda) and single women in the age group 10-29 years, who live in the northeast part of the country. When the offender was a partner/ex., women aged 10-19 years showed the greatest (all-cause) mortality risk at 16.9 [95% CI: 13.9-19.8] times. Higher risk was also observed within the age group 30-59 years when death was attributable to external causes (RR: 74.6, 95% CI: 71.3-77.9). For younger women and girls, there was a clear gradient in (all-cause) mortality risk, with those living in the poorest municipalities at greater risk. Age-specific mortality risk also showed significant variation within and across states. CONCLUSIONS: This analysis suggests that most women exposed to violence will likely experience an increased risk of mortality, regardless of her place of residence, age group, racial/ethnic background, marital status situation, and socio-economic status. The estimated RRs are only an approximation given the design of this analysis and should be interpreted with caution.


Assuntos
Maus-Tratos Conjugais/mortalidade , Violência/estatística & dados numéricos , Adolescente , Adulto , Brasil/epidemiologia , Causas de Morte , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Doenças não Transmissíveis , Fatores de Risco , Pessoa Solteira , Maus-Tratos Conjugais/psicologia , Violência/psicologia , Adulto Jovem
9.
Life Sci ; 212: 168-175, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30292829

RESUMO

Liver cirrhosis is associated with a wide range of cardiovascular abnormalities including hyperdynamic circulation and cirrhotic cardiomyopathy. The pathogenic mechanisms of these cardiovascular changes are multifactorial and include vascular dysregulations. AIM: The present study tested the hypothesis that the systemic vascular hyporesponsiveness in thioacetamide (TAA)-induced liver injury model is dependent on nitric oxide (NO) and cyclooxygenase (COX) derivatives. MAIN METHODS: Wistar rats were treated with TAA for eight weeks to induce liver injury. KEY FINDINGS: The maximal contractile response in concentration-effect curves to phenylephrine was decreased in aorta from TAA-treated rats, but no differences were found in aorta without endothelium, suggesting an endothelium-dependent mechanism in decreased contractile response. There was no difference in the contractile response with and without L-NAME (N(ω)-nitro-l-arginine methyl ester) in rats with liver injury, showing that the TAA treatment impairs NO synthesis. Pre-incubation of the aorta with indomethacin, a COX-inhibitor, normalized the reduced contractile response to phenylephrine in arteries from TAA group. Also, COX-2 and iNOS (inducible nitric oxide syntase) protein expression was increased in aorta from TAA group compared to control group. Animals submitted to TAA treatment had a reduction in systolic blood pressure. Our findings demonstrated that liver injury induced by TAA caused a decrease in aortic contractile response by a COX-dependent mechanism but not by NO release. Also, it was demonstrated an inflammatory process in the aorta of TAA-treated rats by increased expression of COX-2 and iNOS. SIGNIFICANCE: Therefore, there is an essential contribution of COX-2 activation in extra-hepatic vascular dysfunction and inflammation present in cirrhosis induced by TAA.


Assuntos
Aorta Torácica/patologia , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Ciclo-Oxigenase 2/metabolismo , Endotélio Vascular/patologia , Tioacetamida/toxicidade , Doenças Vasculares/etiologia , Animais , Aorta Torácica/enzimologia , Pressão Sanguínea , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Endotélio Vascular/enzimologia , Masculino , Óxido Nítrico/metabolismo , Ratos , Ratos Wistar , Doenças Vasculares/enzimologia
10.
Food Funct ; 9(8): 4419-4428, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30066000

RESUMO

Cancers induced by human papillomavirus (HPV) infection remain a significant public health threat, fueling the study of new therapies. Laurel (Laurus nobilis) compounds and extracts recently showed in vitro activity against HPV-transformed cell lines. This work aims to evaluate the in vivo efficacy and hepatic toxicity of a laurel extract in a transgenic mouse model of HPV16-induced cancer. The extract was administered in drinking water (20 mg per animal per day) for three consecutive weeks, using four experimental groups (n = 10) (group I: HPV16-/- without treatment, group II: treated HPV16-/-, group III: HPV16+/- without treatment and group IV: treated HPV16+/-). Following the treatment period, animals were sacrificed and skin samples were used to classify skin lesions histologically. Toxicological parameters included hematological and biochemical blood markers, splenic and hepatic histology and hepatic oxidative stress. The extract did not prevent the progression of HPV16-induced cutaneous lesions in this model. The treated wild-type animals showed mild hepatitis, while transgenic animals suffered weight loss. However, there were no changes concerning hematological, biochemical and hepatic oxidative stress markers.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Papillomavirus Humano 16/fisiologia , Laurus/química , Infecções por Papillomavirus/virologia , Extratos Vegetais/toxicidade , Neoplasias do Colo do Útero/virologia , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Feminino , Papillomavirus Humano 16/genética , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Transgênicos , Estresse Oxidativo/efeitos dos fármacos , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
11.
Biomed Pharmacother ; 104: 275-279, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29775895

RESUMO

Infection with high-risk human papillomavirus (HPV), most often HPV16, is associated with the development of anogenital and oropharyngeal cancers. Recently, ozone therapy was reported to have considerable efficacy against rabbit VX2 tumors, induced by the cottontail rabbit papillomavirus. The present study aims to determine whether similar results can be obtained in HPV16-transgenic mice, possibly paving the way for new therapeutic options against HPV-induced cancers. HPV16-transgenic and wild-type, female, 20 weeks-old mice were injected intraperitoneally with medical O3/O2 (80░mL/kg, at O3 50░µg/mL), once a day, for 5 consecutive days. The animals were sacrificed at 25 weeks-old, and skin samples were analyzed histologically to study tumour progression. Blood and internal organ samples were used to study toxicological parameters. 85.7% of untreated transgenic mice showed dysplastic skin lesions, compared with 28.6% of O3-treated mice. This was associated with a marked reduction of dermal inflammation associated with those lesions. No significant changes were observed in any toxicological parameters. These preliminary results support the hypothesis that O3 therapy is effective against papillomavirus-induced lesions, particularly against those induced by the most common high-risk virus, HPV16. Further studies are needed to confirm the mechanisms underlying these effects.


Assuntos
Papillomavirus Humano 16/patogenicidade , Neoplasias/tratamento farmacológico , Ozônio/farmacologia , Dermatopatias/tratamento farmacológico , Animais , Progressão da Doença , Feminino , Camundongos , Camundongos Transgênicos , Neoplasias/virologia , Infecções por Papillomavirus/complicações , Coelhos , Pele/efeitos dos fármacos , Pele/virologia , Dermatopatias/virologia , Resultado do Tratamento
12.
Immunobiology ; 222(11): 1004-1013, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28641918

RESUMO

Leptospirosis is globally widespread neglected disease, affecting most mammalian species. Clinical signs can be confused with other diseases which make the diagnosis and treatment difficult. Chemokines and cytokines are known for their role in the inflammatory and immune response to infections. The profile determination of chemokines' expressions in the course of infection may elucidate the defense mechanisms of the host and support the search for effective treatment strategies. We investigated the mechanisms of innate immunity through the comparison of chemokines induced during infection with L. interrogans in mice with different levels of susceptibility. We used lung and spleen tissues samples of mice from C3H/HeJ, C3H/HePas and Balb/c, respectively sensitive, intermediate susceptibility and resistant to the pathogen. The inoculation of L. interrogans in C3H/HeJ mice led a comparatively smaller change in chemokines expression in both spleen and lung tissues. In samples from spleens and lungs of C3H/HePas and Balb/c the higher increases occurred on CXCL9, CXCL16, CXCL5, CCL8 and CCL5 in Balb/c. Given the same genetic background, the differences in the responses of C3H/HePas compared to C3H/HeJ mice strongly suggest the role of chemokines for the survival of parental strain. Therefore, the greatest increase in CXC chemokines appears to be efficient to induce migration of cells to the secondary lymphoid organs and affected tissues, which is important to control infection. Overall, CXC chemokines are important for the activation and attraction of T cell and may influence the course and control of the infection in resistant Balb/c mice.


Assuntos
Quimiocinas/metabolismo , Leptospira/imunologia , Leptospirose/patologia , Pulmão/fisiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Células Cultivadas , Progressão da Doença , Regulação Bacteriana da Expressão Gênica , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Interações Hospedeiro-Patógeno , Imunidade Inata , Mediadores da Inflamação/metabolismo , Leptospirose/imunologia , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Receptor 4 Toll-Like/metabolismo
13.
Oper Dent ; 42(3): 335-341, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28467265

RESUMO

OBJECTIVE: The objective of this study was to evaluate the influence of adhesives with different 10-MDP concentrations on the shear bond strength of a resin cement to zirconia. METHODS AND MATERIALS: Six experimental adhesives were prepared with the following composition: camphorquinone, 1,2-diaminobenzene, butylhydroxytoluene, diphenyliodonium hexafluorophosphate, 2-hydroxyethyl methacrylate triethylene glycol dimethacrylate, ethoxylated bisphenol A glycol dimethacrylate, urethane dimethacrylate, bisphenol A diglycidyl methacrylate, and ethanol. The 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) monomer was added at 0wt%, 3wt%, 6wt%, 9wt%, 12wt%, or 15wt%. Three commercially available adhesives were evaluated: Single Bond Universal, Single Bond 2, and Signum Zirconia Bond. Resin cement cylinders made with RelyX Ultimate were bonded to yttria-stabilized tetragonal zirconia polycrystal with one of the evaluated adhesives and were subjected to the shear bond strength evaluation. Failure modes were analyzed with a stereoscopic loupe. Statistical analyses were performed with one-way analysis of variance and the Tukey's Honestly Significant Difference test (α=0.05). Pearson's was used to correlate the percentage of 10-MDP in the experimental adhesives and shear bond strength. RESULTS: There were significant differences between adhesives (p<0.00001). The highest shear bond strength values were obtained with the Signum Zirconia Bond and Single Bond Universal. Single Bond 2 showed the lowest values. There were no differences between experimental adhesives. All groups showed adhesives failures. A nonlinear correlation was found between bond strength and percentage of 10-MDP in experimental adhesives (r=0.872). CONCLUSIONS: The commercially available adhesives indicated for bonding to zirconia showed the highest bonding values.


Assuntos
Colagem Dentária/métodos , Cimentos Dentários/química , Materiais Dentários/química , Metacrilatos/química , Zircônio/química , Bis-Fenol A-Glicidil Metacrilato , Resinas Compostas , Análise do Estresse Dentário , Teste de Materiais , Resistência ao Cisalhamento , Propriedades de Superfície
14.
J Neural Eng ; 14(4): 041001, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28452331

RESUMO

Optogenetics is a relatively new technology to achieve cell-type specific neuromodulation with millisecond-scale temporal precision. Optogenetic tools are being developed to address neuroscience challenges, and to improve the knowledge about brain networks, with the ultimate aim of catalyzing new treatments for brain disorders and diseases. To reach this ambitious goal the implementation of mature and reliable engineered tools is required. The success of optogenetics relies on optical tools that can deliver light into the neural tissue. Objective/Approach: Here, the design and manufacturing approaches available to the scientific community are reviewed, and current challenges to accomplish appropriate scalable, multimodal and wireless optical devices are discussed. SIGNIFICANCE: Overall, this review aims at presenting a helpful guidance to the engineering and design of optical microsystems for optogenetic applications.


Assuntos
Encéfalo/citologia , Desenho de Equipamento/métodos , Optogenética/métodos , Interface Usuário-Computador , Animais , Encéfalo/fisiologia , Eletrodos Implantados , Desenho de Equipamento/instrumentação , Humanos , Optogenética/instrumentação
15.
Int J Impot Res ; 29(4): 157-159, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28405028

RESUMO

Greater vibrotactile sensitivity has been related to better erectile function in men, and vibrotactile and pressure tactile sensitivity have been related to better sexual function in women. Our previous study found that, for both sexes, greater recalled body awareness during last sexual relation correlated with greater recalled desire and arousal. Using the same sample of that study (68 women and 48 men, recruited in the Lisbon area, Portugal), we tested if greater recalled body awareness during last sexual relation correlates with tactile pressure sensitivity, as assessed by von Frey microfilaments. In simple and partial correlations controlling for social desirability and smoking before last sex, the hypothesis was confirmed for women, but not for men. Greater tactile sensitivity might enhance sexual arousal through greater awareness of the body during sex, and/or more frequent and pleasant body sensations during sex might lead to greater tactile sensitivity in nonsexual situations. Pressure sensitivity might be more closely linked to sexual arousal in women than in men.


Assuntos
Conscientização/fisiologia , Coito/fisiologia , Dedos , Percepção do Tato/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pressão , Limiar Sensorial/fisiologia , Parceiros Sexuais , Adulto Jovem
16.
Eur J Clin Nutr ; 71(11): 1341-1344, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28294169

RESUMO

BACKGROUND/OBJECTIVES: The aim of this study was to verify the agreement between body fat percentage (%BF) values evaluated by air displacement plethysmograph (ADP) and body adiposity index (BAI) in adults with Down's syndrome (DS). SUBJECTS/METHODS: Forty-five adults with DS volunteered to participate in this study (19 women; age 28.7±8.5 years and 26 men; age 29.1±8.8 years). The %BF was measured by ADP (%BFADP) and estimated by anthropometric measures [%BF=(hip circumference/height)1.5-18] (%BFBAI). Agreement between methods was evaluated by paired t-test, Pearson's correlation coefficient and Bland-Altman analysis. RESULTS: Although high correlation coefficients were found between %BFADP and %BFBAI for women (r=0.78, P<0.05) and men (r=0.87, P<0.05), significant differences were observed between methods for both sexes (38.9±8.9 vs 42.5±8.5% for women, and 25.8±11.3 vs 32.6±5.4% for men in %BFADP and %BFBAI, respectively). Moreover, Bland-Altman analysis showed that the mean error estimate was +3.6 (95%CI, -7.59 to 14.79) in women and +6.74 (95%CI, -7.25 to 20.72) in men. CONCLUSIONS: The results indicate that BAI seems to be a limited method to evaluate %BF in women and in men with DS.


Assuntos
Tecido Adiposo , Composição Corporal , Síndrome de Down/fisiopatologia , Adulto , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pletismografia , Valor Preditivo dos Testes
17.
Transbound Emerg Dis ; 64(5): 1371-1379, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27615361

RESUMO

Over recent years, a growing number of papillomaviruses have been identified, which cause a wide range of lesions in domestic and wild animals. Papillomavirus-induced lesions may have a great impact on animal health, and some diseases observed in farm animals are associated with significant economic losses. This concise review brings together recent advancements on animal papillomavirus research, providing the scientific community and veterinary practitioners with an update on this rapidly evolving field. Among others, bovine, canine and feline papillomaviruses (BPV, CPV and FcaPV) are most extensively discussed, in view of the recent discovery of new viral types and their worldwide importance for animal health. Feline papillomaviruses 2 is an emerging, highly prevalent pathogen in domestic cats, associated with a subset of malignant skin lesions. Aspects related to cross-species infection by BPV and its environmental co-factors are also addressed. Animal papillomaviruses are also fascinating models for studying molecular and cell biology and have recently inspired some major breakthroughs. Overall, it is clear that additional, international and systematic efforts are needed to clarify which lesions are caused by which viral types and to develop experimental models for studying animal papillomavirus.


Assuntos
Doenças do Gato/virologia , Doenças dos Bovinos/virologia , Doenças do Cão/virologia , Papillomaviridae/classificação , Infecções por Papillomavirus/veterinária , Bem-Estar do Animal , Animais , Doenças do Gato/patologia , Gatos , Bovinos , Doenças dos Bovinos/patologia , Doenças do Cão/patologia , Cães , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia
18.
Biomed Pharmacother ; 81: 273-280, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27261604

RESUMO

BACKGROUND: Breast cancer remains a leading cause of death by cancer worldwide. It is commonly accepted that angiogenesis and the expression of angiogenic factors such as vascular endothelial growth factor-A (VEGF-A) is associated with the increased risk of metastasis and poor patient outcome. OBJECTIVE: This work aimed to evaluate the effects of long-term exercise training on the growth and vascularization of mammary tumors in a rat model. MATERIALS AND METHODS: Fifty female Sprague-Dawley rats were divided into four groups: two N-methyl-N-nitrosourea (MNU)-exposed groups (exercised and sedentary) and two control groups (exercised and sedentary). MNU was administered once, intraperitoneally at 7 weeks-old. Animals were then exercised on a treadmill for 35 weeks. Mammary tumors were evaluated using thermography, ultrasonography [Power Doppler (PDI), B Flow and contrast-enhanced ultrasound (CEUS)], and immunohistochemistry (VEGF-A). RESULTS: Both, MNU sedentary and exercised groups showed 100% of tumor incidence, but exercised animals showed less tumors with an increased latency period. Exercise training also enhanced VEGF-A immunoexpression and vascularization (microvessel density, MVD) (p<0.05), and reduced histological aggressiveness. Ultrasound and thermal imaging analysis confirmed the enhanced vascularization of tumors on exercised animals. CONCLUSION: Long-term exercise training increased VEGF-A expression, leading to enhanced tumor vascularization and reduced tumor burden, multiplicity and histological aggressiveness.


Assuntos
Neoplasias Mamárias Experimentais/irrigação sanguínea , Neoplasias Mamárias Experimentais/fisiopatologia , Neovascularização Patológica/fisiopatologia , Condicionamento Físico Animal , Animais , Feminino , Imuno-Histoquímica , Neoplasias Mamárias Experimentais/diagnóstico por imagem , Neoplasias Mamárias Experimentais/patologia , Tamanho do Órgão , Ratos Sprague-Dawley , Termografia , Fatores de Tempo , Ultrassonografia , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Expert Opin Drug Discov ; 11(6): 599-607, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27077499

RESUMO

INTRODUCTION: Urinary bladder cancer (UBC) is the second most frequent malignancy of the urinary system and the ninth most common cancer worldwide, affecting individuals over the age of 65. Several investigations have embarked on advancing knowledge of the mechanisms underlying urothelial carcinogenesis, understanding the mechanisms of antineoplastic drugs resistance and discovering new antineoplastic drugs. In vitro and in vivo models are crucial for providing additional insights into the mechanisms of urothelial carcinogenesis. With these models, various molecular pathways involved in urothelial carcinogenesis have been discovered, allowing therapeutic manipulation. AREAS COVERED: This paper provides critical information on existing in vitro and in vivo models to screen the efficacy and toxicity of innovative UBC therapies and point out the challenges for new and improved models. EXPERT OPINION: In our opinion, results obtained with in vitro and in vivo models should be interpreted together, as a set of delicate biological tools that can be used at different stages in the drug discovery process, to address specific questions. With the development of new technologies, new assays and biomarkers are going to play an important role in the study of UBC. The molecular diagnostics and genomic revolution will not only help to develop new drug therapies, but also to achieve tailored therapies.


Assuntos
Antineoplásicos/uso terapêutico , Desenho de Fármacos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Idoso , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Descoberta de Drogas/métodos , Resistencia a Medicamentos Antineoplásicos , Humanos , Modelos Moleculares , Técnicas de Diagnóstico Molecular , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Urotélio/patologia
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