Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 123
Filtrar
1.
Mol Biol Rep ; 46(1): 1349-1356, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30554313

RESUMO

In this work we investigated the possible cellular changes induced by C-phycocyanin (C-PC) in erythroleukemic cells with (K562-Lucena and FEPS) and without (K562) the multidrug resistance (MDR) phenotype. The reactive oxygen levels (ROS) (evaluated by fluorimetry) were increased relative to the control in K562 and K562-Lucena cells treated with 100 µg/mL and were not increased in FEPS cells. The expression of the following genes related to resistance was evaluated by real-time PCR: COX2, ALOX5, ABCB1 and ABCC1. Treatment with 100 µg/mL of C-PC increased COX2 and ABCB1 expression in K562-Lucena cells and reduced expression of ALOX5 in K562-Lucena and FEPS cells. ROS levels appear to be involved in biological responses to C-PC in K562 and K562-Lucena cells, although expression of the genes studied here was only modified by C-PC in the K562-Lucena cell line. Thus, it is possible to suggest that C-PC modulates the expression of COX2 and ABCB1 for the K562-Lucena in a ROS-dependent manner and the expression of ALOX5 for the FEPS in a ROS-independent manner; however, more studies are needed to elucidate these mechanisms.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ficocianina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Necrose
2.
Nutr Metab Cardiovasc Dis ; 29(1): 69-78, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30459074

RESUMO

BACKGROUND AND AIMS: Polyphenol-rich diets have been associated with reduced risk of cardiovascular disease (CVD). However, few prospective epidemiological studies have examined the relationship between classes of ingested polyphenols and risk of CVD. Our aim was to evaluate the association between polyphenol intake and risk of major cardiovascular events in a prospective Spanish cohort. METHODS AND RESULTS: We included 17,065 university graduates (60.7% women, mean age: 37.2 years, age range: 20-89) followed-up for a mean of 10.1 years. Polyphenol intake was assessed at baseline using a validated semi-quantitative 136-item food frequency questionnaire and matching food consumption data with the Phenol-Explorer database. Cox proportional hazards models were used to estimate the adjusted hazard ratios (HR) and 95% confidence intervals (95% CI) for incident cardiovascular events (myocardial infarction, stroke or cardiovascular death). Cherries, chocolate, coffee, apples, and olives were the major sources of variability in polyphenol intake. Participants with higher flavonoids intake (fifth quintile) had a 47% lower incidence of cardiovascular events compared to those in the lowest quintile (HR: 0.53, 95% CI: 0.29-0.98; P for trend = 0.09) after adjusting for potential confounders. The results were non-significant for other polyphenol types. CONCLUSION: The intake of flavonoids showed an inverse association with risk of cardiovascular events in a prospective cohort of Spanish middle-aged adult university graduates. REGISTRATION NUMBER FOR CLINICAL TRIALS: NCT02669602 in Clinical Trials.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta , Polifenóis/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Inquéritos sobre Dietas , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Polifenóis/classificação , Estudos Prospectivos , Fatores de Proteção , Fatores de Risco , Espanha/epidemiologia , Estudantes , Fatores de Tempo , Universidades , Adulto Jovem
3.
BMC Public Health ; 19(1): 775, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31215435

RESUMO

BACKGROUND: The food environment can influence opportunities and barriers to food access. This study aimed to investigate whether access to healthy foods varies according to store types and the socioeconomic status of the users of the public health promotion program in Brazil, known as the Health Academy Program. METHODS: A total of 18 Health Academy Program centers were selected via simple conglomerate sampling. Health Academy Program users living up to 1 km from the food stores were evaluated (n = 2831). Their socioeconomic status was investigated via face-to-face interviews. The food stores were audited through direct observation. Variables included the community nutrition environment (type and location) and consumer nutrition environment (healthy food store index, involving variables such as availability, variety, and advertising of healthy and unhealthy products). Multiple linear regression analysis was performed to examine the association between access to healthy foods, socioeconomic status, and food store type. RESULTS: A total of 336 stores were investigated. The majority were specialty fruit and vegetable markets/stores or open-air food markets. Access to healthy food was only associated with the food store type. An increase of 1% in the availability of specialized fruits and vegetable markets or open-air food markets and supermarket raised healthy food store index values by 0.12 and 0.07, respectively. CONCLUSIONS: Public food supply policies aimed at improving the diet quality of the population and reducing inequality in access should prioritize the implementation of stores of better quality, such as specialty fruit and vegetable markets and open-air food markets.


Assuntos
Comércio/estatística & dados numéricos , Abastecimento de Alimentos/estatística & dados numéricos , Frutas , Classe Social , Verduras , Idoso , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Reprod Domest Anim ; 52(6): 1067-1073, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28744919

RESUMO

It has been evident the improvement of in vitro embryo production (IVEP) in dairy cows. Nevertheless, it is known that differences in the number and quality of oocytes between taurine and zebu females impact the efficiency and economic viability of IVEP. As the insulin-like growth factor (IGF) system is related to follicular and oocyte development, we aimed to quantify mRNA abundance of IGF system members and pregnancy-associated plasma protein-A (PAPPA) in the cumulus-oocyte complexes (COCs) of Gir, 1/2 Holstein × 1/2 Gir and Holstein cows. Four pools of 30 immature COCs from Gir, 1/2 Holstein × 1/2 Gir and Holstein cows were obtained by ovum pickup (OPU), and the oocytes and cumulus cells (CC) were mechanically separated and stored at -80°C. Total RNA was extracted from pools of 30 oocytes and their respective CC. Expression of target genes was assessed by real-time RT-PCR. In oocytes, the abundance of IGFR1 mRNA was higher (p < .05) in Gir cows compared with the other breeds. In contrast, in CC, mRNA encoding IGF2 (p < .05), IGFR2 (p < .05) and IGFBP4 (p < .01) was higher in Holstein donors compared with Gir and 1/2 Holstein × 1/2 Gir cows. Additionally, the abundance of PAPPA mRNA was higher in oocytes (p < .001) and CC (p < .01) in Gir and 1/2 Holstein × 1/2 Gir cows compared with the Holstein donors. In conclusion, the higher abundance of PAPPA mRNA in the oocytes and CC from Gir and cross-breed donors combined with the low expression of IGFBP4 in the CC suggests an enhancement of the bioavailability of IGF-free when compared with Holstein COCs.


Assuntos
Bovinos/genética , Bovinos/metabolismo , Células do Cúmulo/metabolismo , Oócitos/metabolismo , Somatomedinas/genética , Somatomedinas/metabolismo , Animais , Feminino , Expressão Gênica , Recuperação de Oócitos/veterinária , Proteína Plasmática A Associada à Gravidez/genética , Proteína Plasmática A Associada à Gravidez/metabolismo , RNA Mensageiro , Análise de Sequência de RNA , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
5.
Genet Mol Res ; 16(1)2017 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-28218792

RESUMO

Casearia grandiflora (Salicaceae) is a typical Cerrado species adapted to disturbed environments, making it useful for restoration projects. Knowledge of genetic diversity is important for establishing conservation strategies for this species. This study aimed to compare chloroplast haplotype diversity and structure of C. grandiflora, under the assumption that protected areas hold greater genetic diversity than disturbed areas. The populations studied are from Parque Nacional de Sete Cidades Conservation Unit and from the surroundings of the city of Cocal de Telha, both located in the State of Piauí. Molecular analyses were performed with seven chloroplast microsatellite loci. The number of private haplotypes and haplotype diversity were higher in the conservation unit, which reinforces the importance of these areas in maintaining biodiversity. Analysis of molecular variance showed that most of the genetic variation is found within populations, with a moderate divergence between them (FST = 0.14). The Bayesian analysis and discriminant analysis of principal components suggested that populations are not structured, revealing that a set of individuals from Parque Nacional de Sete Cidades were more divergent within populations than between them. Since literature has little information on C. grandiflora, the results of this study provide important contribution to a better understanding of the specie's genetic diversity.


Assuntos
Casearia/genética , Cloroplastos/genética , DNA de Cloroplastos/análise , Variação Genética , Teorema de Bayes , Conservação dos Recursos Naturais , Análise Discriminante , Genética Populacional , Haplótipos , Repetições de Microssatélites
6.
Spinal Cord ; 54(2): 145-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26215910

RESUMO

INTRODUCTION: Increased demands on the upper extremities (UE) have been associated with a higher occurrence of musculoskeletal pain in individuals with spinal cord injury (SCI). STUDY DESIGN: This is a cross-sectional retrospective study. OBJECTIVE: The aim of this study was to characterize SCI subjects with musculoskeletal pain in the UE and to determine which variables could predict musculoskeletal pain in these individuals. SETTING: The study was conducted in SARAH Network of Rehabilitation Hospitals, Brasília, Brazil. METHODS: Five hundred sixty-four electronic medical records were investigated through a retrospective, exploratory and descriptive analysis to identify individuals with UE pain. A logistic regression model was applied to estimate (odds ratios) whether gender, age, the level of injury, severity of injury, time of injury, body mass index, type of mobility and locomotion aid could predict the occurrence of musculoskeletal pain. RESULTS: The prevalence of musculoskeletal pain in the UE was 27.7%. The odds of having musculoskeletal pain were two times higher among woman and tetraplegic patients; those over 41 years of age had twice the frequency of pain than did those <24.7 years; <1 year of injury was a predictor of musculoskeletal pain, compared with the other quartiles (1.1-2.8, 2.9-6.8 and 6.9+ years of injury). There were no differences between the wheelchair and ambulatory individuals. CONCLUSION: Female individuals, those with tetraplegia, aged >40 years and <1 year of injury showed an increased risk of musculoskeletal pain.


Assuntos
Artralgia/diagnóstico , Artralgia/epidemiologia , Quadriplegia/epidemiologia , Traumatismos da Medula Espinal/diagnóstico , Traumatismos da Medula Espinal/epidemiologia , Extremidade Superior , Adolescente , Adulto , Distribuição por Idade , Idoso , Brasil/epidemiologia , Causalidade , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/estatística & dados numéricos , Prevalência , Prognóstico , Quadriplegia/psicologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco/métodos , Sensibilidade e Especificidade , Distribuição por Sexo , Adulto Jovem
7.
Genet Mol Res ; 14(4): 18003-8, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26782447

RESUMO

Babassu (Orbignya phalerata Martius) is one of the most important palms in Brazil because of the largest morphological variation, wide geographic distribution, and high socio-economic importance. The diversity present in babassu germplasm should be protected against loss to ensure their use with high productivity. Study of the available variability in populations of babassu is necessary to develop conservation strategies. The study of genetic variability can be conducted using molecular markers and many of these studies require significant quantity of high-quality DNA. The present study aimed to effect comparison among eight DNA extraction methods in case of O. phalerata. The quality and concentration of nucleic acids were analyzed by spectrophotometry and integrity of DNA was ascertained by agarose gel electrophoresis. The spectrophotometry revealed that some methods resulted in high levels of concentration of nucleic acids, in which values of the ratio A260/280 and A260/230 were outside the range of purity. The agarose gel electrophoresis established the concentration and integrity of DNA. The methods of Murray and Thompson (1980) and Ferreira and Grattapaglia (1998) did not result in satisfactory quantities of DNA. Conversely, the method proposed by Khanuja et al. (1999) resulted in DNA of adequate quality and quantity that could be satisfactorily used for amplification reactions performed with two ISSR primers.


Assuntos
Arecaceae/genética , DNA de Plantas/isolamento & purificação , Genômica , Brasil , DNA de Plantas/genética
8.
Genet Mol Res ; 13(2): 4486-93, 2014 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-25036353

RESUMO

Molecular markers are important for characterizing the genetic diversity of plants and can provide the basis for strategies to protect and conserve endangered populations. However, numerous molecular techniques are used, requiring an evaluation of fast and efficient methods to extract DNA. Since molecular studies of Caesalpinia ferrea are rare, it is important to develop and/or adapt a DNA extraction protocol that produces quality DNA samples to enable the design of strategies for the conservation of this threatened species. This study aimed to compare five methods for DNA extraction and to determine the most efficient protocol for C. ferrea. Sufficient genomic DNA was obtained from the leaves of C. ferrea using all the tested protocols to perform techniques involving molecular markers. Two protocols based on the detergent cetyl trimethyl ammonium bromide, as well as a commercial kit, yielded high concentrations of pure DNA. However, when polymerase chain reaction amplifications were performed, DNA was only successfully amplified from extractions performed with the commercial kit, which produced sufficient genomic DNA of good quality from the leaves of C. ferrea to perform techniques involving molecular markers.


Assuntos
Caesalpinia/genética , DNA de Plantas/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Brometos/química , Detergentes/química , Folhas de Planta/genética , Compostos de Amônio Quaternário/química , Kit de Reagentes para Diagnóstico
9.
Artigo em Inglês | MEDLINE | ID: mdl-38697879

RESUMO

INTRODUCTION: Although some studies have reported the association between uric acid (UA) and hypertension, evidence on prehypertension is still lacking. Therefore, the objective of this study was to determine the levels of UA and other cardiovascular markers among prehypertensive and hypertensive patients and assess their risk for developing arterial hypertension. METHODS: 157 individuals were recruited: 67 normotensive, 23 pre-hypertensive and 67 hypertensive. Blood samples were collected to measure biochemical parameters and anthropometric measurements and blood pressure were evaluated. We calculated the product of lipid accumulation and the visceral adiposity index to assess cardiovascular risk. RESULTS: Our data showed an increase in UA levels in normotensives (4.9±1.3mg/dL), prehypertensives (5.2±1.3mg/dL) and hypertensives (5.9±1.6mg/dL) (p=0.004). We found a higher frequency of hyperuricemia in the hypertensive group (34.3%) than in the normotensive group (13.4%, p<0.05). Hypertensive volunteers had lower levels of HDL-C (p=0.004 and p=0.003) and higher body mass indexes (p<0.001 and p=0.007), glucose (p<0.001 and p=0.033), triglycerides (p=0.001 and p=0.005), visceral adiposity index (p<0.001 and p=0.002) and lipid accumulation product (p<0.001 and p=0.007) than normotensive and prehypertensive participants. We also observed that individuals with UA≥6.2mg/dL had an increased risk of hypertension of 4.77 (p=0.003) compared to individuals with levels≤4.3mg/dL. CONCLUSION: Our results showed that UA is associated with increased blood pressure and unfavorable changes in anthropometric and biochemical parameters, which represent risk factors for hypertension and cardiovascular diseases.

10.
Lett Appl Microbiol ; 57(1): 19-25, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23488866

RESUMO

UNLABELLED: Roughly 200 000 000 people in 74 countries infected with schistosomes all share the fact that they came in contact freshwater harbouring infected snails. The aim of the study is to characterize the microbiota of wild and laboratory-reared snails of Biomphalaria glabrata from Pernambuco, Brazil. The microbiota of these molluscs was identified biochemically by the VITEK 2 automated microbiological system. Antimicrobial susceptibility testing was carried out by the disc diffusion method with ß-lactam antibiotics, aminoglycosides, quinolones, folate pathway inhibitors, fenicols and tetracyclines. The results showed that all bacteria identified were gram-negative, including 11 bacterial genera: Aeromonas, Citrobacter, Enterobacter, Cupriavidus, Rhizobium, Stenotrophomonas, Pseudomonas, Klebsiella, Acinetobacter, Vibrio and Sphingomonas. Regarding the antimicrobial susceptibility, all the isolates exhibited resistance to amoxicillin and sensitivity to meropenem (beta-lactam antimicrobials). The microbiota of the wild snails consisted predominantly of Enterobacter cloacae, while the laboratory-reared snails predominantly showed Citrobacter freundii and Aeromonas sobria. SIGNIFICANCE AND IMPACT OF THE STUDY: Biomphalaria glabrata is a Brazilian freshwater Planorbidae of great medical relevance as an intermediate host of Schistosoma mansoni. About a month after being infected by one or more miracidia larvae of a compatible schistosome, B. glabrata sheds thousands of cercariae into the water where they seek human skin and, if successful, penetrate to establish infection, eventually taking up residence and maturing in blood vessels of the small intestine. Results obtained from this study aim at targeting novel biological control strategies for schistosomiasis such as paratransgenesis. This is the first study on the microbiota of B. glabrata from Brazil.


Assuntos
Biomphalaria/microbiologia , Biomphalaria/parasitologia , Metagenoma , Schistosoma mansoni , Animais , Brasil , Vetores de Doenças , Humanos , Testes de Sensibilidade Microbiana
11.
J Hum Nutr Diet ; 26(3): 230-3, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23231428

RESUMO

BACKGROUND: The present study aimed to calibrate a food frequency questionnaire (FFQ) using one 24-h recall (R24) associated with foodstuff replicas. METHODS: Calibration was performed by linear regression. Of a probability sample of 150 individuals (>18 years) of the town of Bambui, 98 completed the study. RESULTS: The mean age of the participants was 43.8 years and 63.3% were women. The calibration of the FFQ included sex for the estimation of iron, protein and zinc; and an interaction between sex and R24 was significant for vitamin A and cholesterol models. Age contributed to the vitamin C, polyunsaturated fatty acids, proteins and zinc models, and an interaction between age and R24 was significant for protein and zinc. CONCLUSIONS: Calibration coefficients and many interactions in linear regression models revealed important differences between dietary methods, indicating the complexity encountered when combining two methodologies for estimating food intake.


Assuntos
Inquéritos Nutricionais , Inquéritos e Questionários , Adulto , Ácido Ascórbico/administração & dosagem , Brasil , Calibragem , Colesterol , Dieta , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Ácidos Graxos Insaturados/administração & dosagem , Feminino , Humanos , Modelos Lineares , Masculino , Rememoração Mental , Vitamina A/administração & dosagem , Zinco/administração & dosagem
12.
J Mater Sci Mater Med ; 24(2): 395-403, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23138839

RESUMO

Electroactive materials can be taken to advantage for the development of sensors and actuators as well as for novel tissue engineering strategies. Composites based on poly(vinylidene fluoride), PVDF, have been evaluated with respect to their biological response. Cell viability and proliferation were performed in vitro both with Mesenchymal Stem Cells differentiated to osteoblasts and Human Fibroblast Foreskin 1. In vivo tests were also performed using 6-week-old C57Bl/6 mice. It was concluded that zeolite and clay composites are biocompatible materials promoting cell response and not showing in vivo pro-inflammatory effects which renders both of them attractive for biological applications and tissue engineering, opening interesting perspectives to development of scaffolds from these composites. Ferrite and silver nanoparticle composites decrease osteoblast cell viability and carbon nanotubes decrease fibroblast viability. Further, carbon nanotube composites result in a significant increase in local vascularization accompanied an increase of inflammatory markers after implantation.


Assuntos
Fibroblastos/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Polímeros/farmacologia , Polivinil/química , Animais , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Fibroblastos/fisiologia , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/fisiologia , Polímeros/síntese química , Polímeros/química , Polivinil/farmacologia , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos , Alicerces Teciduais/química
13.
Genet Mol Res ; 12(2): 1155-67, 2013 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-23661440

RESUMO

Genetic diversity and structure were analyzed in 10 accessions belonging to Banco Ativo de Germoplasma de Capsicum located at Federal University of Piauí in northwestern Brazil that receives pepper samples grown in community gardens in various regions and Brazilian states. Selections were made from seeds of C. chinense (4 accessions), C. annuum (5 accessions), and C. baccatum (1 accession). Samples consisting of leaves were collected from 4-10 plants of each accession (a total of 85 plants). Native polyacrylamide gel electrophoresis was used to identify α- and ß-esterase polymorphisms. Polymorphism was clearly detected in 5 loci. Sixteen alleles were found at 5 α/ß-esterase loci of the three Capsicum species. In the C. chinense samples, the highest HO and HE values were 0.3625 and 0.4395, respectively, whereas in C. annuum samples, HO and HE values were 0.2980 and 0.3310, respectively; the estimated HO and HE values in C. chinense samples were higher than those detected in C. annuum samples. A deficit of homozygous individuals was found in C. chinense (FIS = -0.6978) and C. annuum (FIS = 0.7750). Genetic differentiation between C. chinense and C. annuum at these loci was high (FST = 0.1867) indicating that C. chinense and C. annuum are genetically structured species for α/ß- esterase isozymes. The esterase analysis showed high genetic diversity among the C. chinense and C. annuum samples and very high genetic differentiation (FST = 0.6321) among the C. chinense and C. annuum samples and the C. baccatum accession.


Assuntos
Capsicum/genética , Esterases/genética , Polimorfismo Genético , Alelos , Capsicum/metabolismo , Esterases/classificação , Esterases/metabolismo , Loci Gênicos , Genótipo , Isoenzimas , Fenótipo , Filogenia
14.
Transl Psychiatry ; 13(1): 134, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37185805

RESUMO

Obsessive-compulsive disorder (OCD) affects 2-3% of the population. One-third of patients are poorly responsive to conventional therapies, and for a subgroup, gamma knife capsulotomy (GKC) is an option. We examined lesion characteristics in patients previously treated with GKC through well-established programs in Providence, RI (Butler Hospital/Rhode Island Hospital/Alpert Medical School of Brown University) and São Paulo, Brazil (University of São Paolo). Lesions were traced on T1 images from 26 patients who had received GKC targeting the ventral half of the anterior limb of the internal capsule (ALIC), and the masks were transformed into MNI space. Voxel-wise lesion-symptom mapping was performed to assess the influence of lesion location on Y-BOCS ratings. General linear models were built to compare the relationship between lesion size/location along different axes of the ALIC and above or below-average change in Y-BOCS ratings. Sixty-nine percent of this sample were full responders (≥35% improvement in OCD). Lesion occurrence anywhere within the targeted region was associated with clinical improvement, but modeling results demonstrated that lesions occurring posteriorly (closer to the anterior commissure) and dorsally (closer to the mid-ALIC) were associated with the greatest Y-BOCS reduction. No association was found between Y-BOCS reduction and overall lesion volume. GKC remains an effective treatment for refractory OCD. Our data suggest that continuing to target the bottom half of the ALIC in the coronal plane is likely to provide the dorsal-ventral height required to achieve optimal outcomes, as it will cover the white matter pathways relevant to change. Further analysis of individual variability will be essential for improving targeting and clinical outcomes, and potentially further reducing the lesion size necessary for beneficial outcomes.


Assuntos
Transtorno Obsessivo-Compulsivo , Radiocirurgia , Humanos , Brasil , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/cirurgia , Radiocirurgia/métodos , Resultado do Tratamento , Cápsula Interna/diagnóstico por imagem , Cápsula Interna/cirurgia
15.
J Nanosci Nanotechnol ; 12(8): 6804-10, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22962826

RESUMO

Polymer based composites of a-PVDF doped with different NaY zeolite (Na53Al53Si139O384) content were investigated. A good dispersion of NaY zeolite within the polymer matrix is achieved. The introduction of NaY nanoparticles enhance the storage modulus and the dielectric constant at room temperature. The dielectric constant at room temperature increases up to the value of 500 for the 32 wt% composite, at 1 kHz. The increase of the dielectric constant is mainly attributed to interfacial polarization effects. For increasing zeolite content, the nanocomposite conductivity shows two conducting regimes separted by the so called breaking voltage, which is associated to an intrazeolite charge transport. Thermogravimetric results show that the introduction of zeolites affects the thermal degradation of the polymer for low zeolite contents and also indicate the presence of water that also plays an important role in the electrical response of the materials.

17.
Water Sci Technol ; 64(1): 233-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22053480

RESUMO

The treatment of H2S in the biogas produced during anaerobic digestion has to be carried out to ensure the efficient long-lasting use of its energetic potential. The microaerobic removal of H2S was studied to determine the treatment capacity at low and high H2S concentrations in the biogas (0.33 and 3.38% v/v) and to determine the optimal O2 rate that achieved a concentration of H2S of 150 mg/Nm3 or lower. Research was performed in pilot-plant scale digesters of sewage sludge, with 200 L of working volume, in mesophilic conditions with a hydraulic retention time of 20 d. O2 was supplied at different rates to the headspace of the digester to create the microaerobic conditions. The treatment successfully removed H2S from the biogas with efficacies of 97% for the low concentration and 99% for the highest, in both cases achieving a concentration below 150 mg/Nm3. An optimal O2 rate of 6.4 NLO2/Nm3 of biogas when treating the biogas was found with 0.33% (v/v) of H2S and 118 NLO2/ Nm3 of biogas for the 3.38% (v/v) concentration. This relation may be employed to control the H2S content in the biogas while optimising the O2 supply.


Assuntos
Biocombustíveis/análise , Sulfeto de Hidrogênio/análise , Oxigênio/análise , Esgotos/química , Purificação da Água/métodos , Aerobiose , Anaerobiose , Oxirredução , Projetos Piloto , Esgotos/microbiologia , Espanha , Purificação da Água/instrumentação
18.
Braz J Biol ; 83: e243514, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133490

RESUMO

Allium sativum L. is an herb of the Alliaceae family with a specific taste and aroma and medicinal and nutraceutical properties that are widely marketed in several countries. Brazil is one of the largest importers of garlic in the world, despite of its production is restricted and limited to internal consumption. Thus, explore the genetic diversity of commercial garlic conserved at germplasm banks is essential to generate additional genetic information about its economically important crop. A suitable tool for this purpose is the cytogenetic characterisation of these accessions. This study aimed to characterise the cytogenetic diversity among seven accessions of garlic from a Germplasm Bank in Brazil. The karyotypes were obtained by conventional staining and with chromomycin A3 (CMA) and 4,6-diamidino-2-phenylindole (DAPI) fluorochromes. All accessions analysed showed chromosome number 2n = 16, karyotype formula 6M+2SM, symmetrical karyotypes, reticulate interphase nuclei, and chromosomes with uniform chromatin condensation from prophase to metaphase. The fluorochromes staining showed differences in the amount and distribution of heterochromatin along the chromosomes and between accessions studied. Based on the distribution pattern of these small polymorphisms, it was possible to separate the seven accessions into three groups. It was also possible to differentiate some of the accessions individually. One of the results obtained showed a heteromorphic distension of the nucleolar organiser region observed on the chromosome pairs 6 or 7 with peculiar characteristics. It was suggested for example, that the heteromorphic block of heterochromatin (CMA+++/DAPI-) on chromosome 6 of the "Branco Mineiro Piauí" accession can be used as a marker to identify this genotype or may be associated with some character of economic interest.


Assuntos
Alho , Brasil , Bandeamento Cromossômico , Heterocromatina/genética , Cariótipo , Cariotipagem
19.
Braz J Biol ; 81(1): 62-68, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32074172

RESUMO

The objective of this study was to characterize and compare the hematological variables (erythrogram, thrombogram, leukogram and plasma metabolites) of three cichlid species: Cichla monoculus, Cichla temensis and Cichla vazzoleri. A total of 45 specimens were captured in Balbina lake, Presidente Figueiredo, Amazonas, Brazil, with the aid of a rod and reel or hand line, with natural or artificial bait: 15 C. monoculus, 15 C. temensis and 15 C. vazzoleri. Their blood was removed by means of caudal puncture of the dorsal aorta, and hematological data were determined in accordance with methodology previously described in the literature. The erythrogram showed similarities between the species, while the thrombogram showed differences between C. vazzoleri and the other species studied (C. monoculus and C. temensis). The total leukocyte counts for C. temensis and C. vazzoleri were higher than those of C. monoculus. The predominant leukocyte in C. temensis and C. vazzoleri was lymphocytes, whereas it was monocytes in C. monoculus. The plasma metabolites showed differences between the three cichlid species, regarding their glucose, cholesterol, urea and potassium levels. It is concluded that these three species present hematological differentiation, thus indicating that they have differentiated blood-cell immune responses and plasma metabolite physiology.


Assuntos
Ciclídeos , Lagos , Animais , Brasil
20.
J Mech Behav Biomed Mater ; 123: 104690, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34385065

RESUMO

OBJECTIVE: To characterize the effects of aging on the nanomechanical properties and 3D surface topographical parameters of an experimental Zirconia Toughened Alumina (ZTA) composite compared to its respective individual counterpart materials. METHODS: Disk-shaped specimens comprised of three material groups were processed: 1) ZTA 70/30 (70% alumina reinforced with 30% second-generation 3Y-TZP); 2) Zpex (Second-generation 3Y-TZP), and; 3) Al2O3 (High purity Alumina) (n = 10/material, 12 × 1 mm). After synthesis, ceramic powders were pressed, the green-body samples were sintered and polished. Nanoindentation testing was performed to record elastic modulus (E) and hardness (H). Interferometry was utilized to assess 3D surface roughness parameters (Sa, Sq), while X-ray diffraction (XRD) and scanning electron microscope (SEM) assessed the crystalline content and microstructure. All tests were performed before and after simulated aging (134°C, 2.2 bar, 20 h). Statistical analyses were performed using linear mixed-model and least square difference pos-hoc tests (α = 5%). RESULTS: XRD spectra indicated increase of monoclinic peaks for Zpex (~18%) relative to ZTA 70/30 (~2.5%) after aging. Additionally, aging did not affect the surface roughness parameters of ZTA 70/30 and Al2O3, although a significant increase in Sa was recorded for Zpex following aging (~90 nm) (p < 0.001). Al2O3 yielded the highest H and E values (H:21 GPa, E: 254 GPa), followed by ZTA 70/30 (H: 13 GPa, E: 214 GPa) and Zpex (H:11 GPa, E: 167 GPa), all significantly different (p < 0.03). CONCLUSION: ZTA 70/30 and Al2O3 presented high hydrothermal stability with respect to all evaluated variables, where artificial aging significantly increased the monoclinic content and surface roughness of Zpex.


Assuntos
Óxido de Alumínio , Ítrio , Cerâmica , Materiais Dentários , Teste de Materiais , Propriedades de Superfície , Zircônio
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA