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2.
Braz J Biol ; 83: e276465, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422266

RESUMO

The zebrafish has been used in research for over 80 years. In the last three decades, discoveries about the fundamental properties of development, regeneration, cancer, and other diseases have established the zebrafish as an important model organism in biomedical research. This study aimed to evaluate liver alterations in zebrafish by quantitatively assessing the areas occupied by hepatocytes, as well as connective and adipose tissues. Forty-eight adult Danio rerio (38 males and 10 females) of approximately 13 months of age were used. They were divided into four groups, with 12 animals each. The fish were randomly distributed to form the groups, which received a maintenance and/or hypercaloric diet, with or without the addition of physical exercise. The animals underwent six hours of forced exercise (5 cm/s) for thirteen weeks. The animals that practiced physical exercise had a higher volumetric density of the area occupied by hepatocytes (65.92%±1.81 - GMex and 50.75%±2.24 GHex) among the groups. The GH group had a higher volumetric density of the area occupied by connective tissue (15.12%±0.72), followed by the GHex group (13.53%±1.43). Regarding the volumetric density of the area occupied by adipose tissue, the GH group had a higher density (27.21%±1.36), followed by the GHex group (21.66%±1.11) with statistically significant differences. The GMex had a volumetric density of the area occupied by adipose tissue of 3.5%±0.76, while the GM had 5.7%±0.5, with statistical difference. In relation to the animals in the GHex group, they had 20.39% less fat than the animals in the GH group. The animals in the GMex group had 72.47% less fat than those in the GM group. It is concluded that the different dietary constitutions and the imposition of physical exercise were able to modify the structural architecture of the liver of Danio rerio. These are acceptable criteria for modulations, thus aiming at the control and possible interferences directly related to the metabolism of the species and therefore the control of diseases.


Assuntos
Perciformes , Peixe-Zebra , Animais , Feminino , Masculino , Fígado , Dieta , Tecido Adiposo
3.
Acta Neurol Belg ; 121(6): 1799-1806, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33136273

RESUMO

Idiopathic normal pressure hydrocephalus (iNPH) is a condition characterized by gait disturbance, dementia and/or urinary incontinence and enlarged ventricular system due to disturbance of cerebrospinal fluid (CSF). This study aims to describe the long-term experience with patients with iNPH submitted to ventriculoperitoneal shunt (VPS) with the programmable valve STRATA® (Medtronic). We prospectively selected a cohort of patients with a diagnosis of iNPH from January 2010 to April 2013 in a Brazilian tertiary hospital. All patients underwent clinical evaluation, which consists of the Mini-Mental State Examination and Time Up and Go tests and the application of Japanese Scale for Idiopathic Normal Pressure Hydrocephalus in three stages: prior to the TT, 3 h after the TT and 72 h after the TT. Fifty patients were submitted to VPS and followed. There were 32 men and 18 women. Mean age was 77.1 with standard deviation of 10.9. Follow-up time ranged from 96 to 120 months, with mean of 106 months. After 1 year of follow-up, 42 (83%) patients presented with clinical improvement, decreasing to 62% of patients at mid-term follow-up and 38% of patients at late follow-up. Complications occurred in 18% of subjects, needing reoperation in 16%. Our results show relevant clinical impact of shunting in iNPH patients, decreasing over time. Complications should not be underestimated, reaching up to 18% and demanding reoperation in 16% of cases. Thus, although much has been improved with current shunt technology, it is still important to consider the drawbacks of treatment.


Assuntos
Hidrocefalia de Pressão Normal/diagnóstico por imagem , Hidrocefalia de Pressão Normal/cirurgia , Derivação Ventriculoperitoneal/tendências , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Feminino , Seguimentos , Humanos , Hidrocefalia de Pressão Normal/epidemiologia , Masculino , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Derivação Ventriculoperitoneal/métodos
4.
Braz. j. med. biol. res ; 54(2): e10098, 2021. tab, graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1142576

RESUMO

We aimed to present an overview of the literature regarding the interaction between physical exercise and APOE gene polymorphism on cognitive function, particularly in patients with Alzheimer's disease (AD). Firstly, this review focused on the effect of the physical exercise on cognitive function, regardless of APOE gene polymorphism. Some studies have shown that a high level of cardiorespiratory fitness is associated with less neuronal damage with an improvement in memory score tests whereas other studies failed to detect any association between physical exercise and cognitive improvement either in healthy individuals or patients with AD. Taken together, standardized protocols and more longitudinal studies are required to provide a better insight into the effects of physical exercise on cognitive function. Although there is no agreement in the literature regarding the effects of physical exercise on cognitive function, it is well established that it improves social interaction and the feeling of well-being, thereby positively contributing to the quality of life of the elderly. Regarding the influence of physical exercise on cognitive function in APOE ε4 allele carriers, the data trend shows that the carriers of allele ε4 for APOE gene were more responsive to the beneficial effects of physical exercise on cognitive function compared with non-carriers. Nevertheless, studies with larger sample sizes will provide more accuracy about this relationship.


Assuntos
Humanos , Idoso , Idoso de 80 Anos ou mais , Apolipoproteínas E/genética , Exercício Físico , Cognição , Polimorfismo Genético , Qualidade de Vida , Alelos , Doença de Alzheimer/genética , Genótipo
5.
Braz J Med Biol Res ; 54(2): e10098, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33331535

RESUMO

We aimed to present an overview of the literature regarding the interaction between physical exercise and APOE gene polymorphism on cognitive function, particularly in patients with Alzheimer's disease (AD). Firstly, this review focused on the effect of the physical exercise on cognitive function, regardless of APOE gene polymorphism. Some studies have shown that a high level of cardiorespiratory fitness is associated with less neuronal damage with an improvement in memory score tests whereas other studies failed to detect any association between physical exercise and cognitive improvement either in healthy individuals or patients with AD. Taken together, standardized protocols and more longitudinal studies are required to provide a better insight into the effects of physical exercise on cognitive function. Although there is no agreement in the literature regarding the effects of physical exercise on cognitive function, it is well established that it improves social interaction and the feeling of well-being, thereby positively contributing to the quality of life of the elderly. Regarding the influence of physical exercise on cognitive function in APOE ε4 allele carriers, the data trend shows that the carriers of allele ε4 for APOE gene were more responsive to the beneficial effects of physical exercise on cognitive function compared with non-carriers. Nevertheless, studies with larger sample sizes will provide more accuracy about this relationship.


Assuntos
Apolipoproteínas E/genética , Cognição , Exercício Físico , Idoso , Idoso de 80 Anos ou mais , Alelos , Doença de Alzheimer/genética , Genótipo , Humanos , Polimorfismo Genético , Qualidade de Vida
6.
Biochemistry (Mosc) ; 85(10): 1159-1168, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33202201

RESUMO

Type 2 transglutaminase (TG2) is a multifunctional protein involved in various biological processes playing a key regulatory role in cell homeostasis such as cell death and autophagy. New evidence is emerging that support an important role of autophagy in regulating normal hematopoiesis. Prompted by these findings, in this study we investigated in vivo involvement of TG2 in mouse hematopoiesis under normal or nutrient deprivation conditions. We found that the number and rate of differentiation of bone marrow hematopoietic stem cell was decreased in the TG2 knockout mice. We present evidence showing that these effects on hematopoietic system are very likely due to the TG2-dependent impairment of autophagy. In fact, stimulation of autophagy by starvation is able to rescue the block of the differentiation of stem cells progenitors in the TG2 KO mice. It was also shown that the RhoA/ERK½ pathway, known to be essential for regulation of the bone marrow progenitor cells homeostasis, was significantly impaired in the absence of TG2. Hence, this study expanded our knowledge about TG2 discovering a role of this enzyme in regulation of hematopoiesis.


Assuntos
Autofagia , Proteínas de Ligação ao GTP/fisiologia , Células-Tronco Hematopoéticas , Transglutaminases/fisiologia , Animais , Diferenciação Celular , Células Cultivadas , Feminino , Hematopoese , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 2 Glutamina gama-Glutamiltransferase
7.
Sci Rep ; 10(1): 18934, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33144603

RESUMO

Amphibians are models for studying applied ecological issues such as habitat loss, pollution, disease, and global climate change due to their sensitivity and vulnerability to changes in the environment. Developmental series of amphibians are informative about their biology, and X-ray based 3D reconstruction holds promise for quantifying morphological changes during growth-some with a direct impact on the possibility of an experimental investigation on several of the ecological topics listed above. However, 3D resolution and discrimination of their soft tissues have been difficult with traditional X-ray computed tomography, without time-consuming contrast staining. Tomographic data were initially performed (pre-processing and reconstruction) using the open-source software tool SYRMEP Tomo Project. Data processing and analysis of the reconstructed tomography volumes were conducted using the segmentation semi-automatic settings of the software Avizo Fire 8, which provide information about each investigated tissues, organs or bone elements. Hence, volumetric analyses were carried out to quantify the development of structures in different tadpole developmental stages. Our work shows that synchrotron X-ray microtomography using phase-contrast mode resolves the edges of the internal tissues (as well as overall tadpole morphology), facilitating the segmentation of the investigated tissues. Reconstruction algorithms and segmentation software played an important role in the qualitative and quantitative analysis of each target structure of the Thoropa miliaris tadpole at different stages of development, providing information on volume, shape and length. The use of the synchrotron X-ray microtomography setup of the SYRMEP beamline of Elettra Synchrotron, in phase-contrast mode, allows access to volumetric data for bone formation, eye development, nervous system and notochordal changes during the development (ontogeny) of tadpoles of a cycloramphid frog Thoropa miliaris. As key elements in the normal development of these and any other frog tadpole, the application of such a comparative ontogenetic study, may hold interest to researchers in experimental and environmental disciplines.


Assuntos
Anuros/crescimento & desenvolvimento , Larva/ultraestrutura , Microtomografia por Raio-X/veterinária , Algoritmos , Animais , Processamento de Imagem Assistida por Computador , Larva/crescimento & desenvolvimento , Síncrotrons
8.
J Appl Microbiol ; 125(5): 1296-1307, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30053334

RESUMO

AIMS: To determine the effects of cytochalasin E, isolated from the extremophile fungus Aspergillus felis, on the cells of Paracoccidioides brasiliensis Pb18. METHODS AND RESULTS: Cytochalasin E showed a minimal inhibitory concentration of 3·6 µmol l-1 and minimum fungicidal concentration of 7·2 µmol l-1 on P. brasiliensis by in vitro microdilution and IC50 >964·0 µmol l-1 on murine macrophages. Its selectivity index (>263) indicated that this compound has selectivity for fungal cells. Morphological alterations were determined by optical and fluorescence microscopy, as well as scanning and transmission electron microscopy. Cytochalasin E affected P. brasiliensis bud-forming pseudohyphae, cell morphology, cell walls and cell membranes; caused the release of cellular material; and resulted in the production of reactive oxygen species. In murine macrophages, it affected cytoskeletal actin and inhibited phagocytosis. CONCLUSION: Cytochalasin E may be useful as an antifungal prototype against P. brasiliensis and in studies on phagocytosis. SIGNIFICANCE AND IMPACT OF THE STUDY: Paracoccidioides spp. are the etiological agents of paracoccidioidomycosis (PCM). Treatment is prolonged to control the clinical manifestations and prevent relapse. The study on the effects of cytochalasin E in P. brasiliensis is important because it can be used as a prototype for new antifungal drugs and consequently, broadens the treatment options for PCM.


Assuntos
Antifúngicos/farmacologia , Citocalasinas/farmacologia , Paracoccidioides/efeitos dos fármacos , Antifúngicos/isolamento & purificação , Aspergillus/química , Citocalasinas/isolamento & purificação , Testes de Sensibilidade Microbiana
9.
Med Oral Patol Oral Cir Bucal ; 23(3): e262-e268, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29680841

RESUMO

BACKGROUND: Oral lichen planus (OLP) is a chronic inflammatory disease mediated by T cells, which manifests as reticular (white) or erosive (red) lesions, that are eventually painful. Oral lichenoid lesion (OLL) are distinguished from OLP by the presence of precipitating factors. The aim of this study was to evaluate whether the presence of metallothionein, which is involved in anti-apoptotic pathways and the anti-oxidative response, could serve as a differential diagnostic for OLP and OLL. MATERIAL AND METHODS: We evaluated the expression of metallothionein in 40 cases of OLP and 20 cases of OLL using immunohistochemistry. RESULTS AND CONCLUSIONS: White OLP has higher concentrations of metallothionein than red OLP in basal and parabasal layers. Moreover, metallothionein was more frequently observed in the cytoplasm and nuclei of basal cells in OLP patients compared to the same regions of OLL cases. Metallothionein levels are related to OLP severity and may contribute to a differential diagnosis between OLP and OLL.


Assuntos
Amálgama Dentário , Líquen Plano Bucal/diagnóstico , Líquen Plano Bucal/metabolismo , Metalotioneína/biossíntese , Adulto , Amálgama Dentário/efeitos adversos , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Boca/diagnóstico , Doenças da Boca/etiologia , Doenças da Boca/patologia
10.
Zoonoses Public Health ; 65(5): 501-504, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29441690

RESUMO

Hepatitis E virus (HEV) is an emerging pathogen that can be transmitted through contaminated raw or undercooked meat derived from domestic pigs. HEV infections have been documented among pig herds, pig products and environmental samples raising concern about the spread of the virus. HEV genotypes 3 and 4 are considered zoonotic and have been linked to human cases. HEV was detected in 51 of 335 bile samples (15.2%) from healthy pigs in Minas Gerais, Brazil. Phylogenetic analysis of partial sequences from ORF1 and ORF2 regions yielded discordant results, assigning isolates to subtypes 3c and 3i, respectively, suggesting intragenotypic HEV recombination.


Assuntos
Vírus da Hepatite E/isolamento & purificação , Hepatite E/veterinária , Doenças dos Suínos/virologia , Animais , Brasil/epidemiologia , Hepatite E/epidemiologia , Vírus da Hepatite E/genética , Filogenia , Suínos , Doenças dos Suínos/epidemiologia
11.
Braz. j. med. biol. res ; 51(2): e6808, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889020

RESUMO

Pituitary adenomas account for 10-15% of primary intracranial tumors. Growth hormone (GH)-secreting adenomas account for 13% of all pituitary adenomas and cause acromegaly. These tumors can be aggressive, invade surrounding structures and are highly recurrent. The objective of this study was to evaluate E-cadherin, Slug and neural cell adhesion molecule (NCAM) expression in GH-secreting pituitary adenomas and its relationship to tumor invasiveness. A cross-sectional study of patients who underwent hypophysectomy due to GH-secreting pituitary adenoma from April 2007 to December 2014 was carried out. The medical records were reviewed to collect clinical data. Immediately after surgery, tumor samples were frozen in liquid nitrogen and stored in a biofreezer at -80°C for assessment of E-cadherin 1 (CDH1), SLUG (SNAI2), and NCAM (NCAM1) by real-time PCR. The samples were fixed in formalin and embedded in paraffin for immunohistochemical analysis of E-cadherin and NCAM. Thirty-five patients with acromegaly were included in the study. Of these, 65.7% had invasive tumors. Immunohistochemically, E-cadherin was expressed in 96.7% of patients, and NCAM in 80% of patients. There was no statistically significant relationship between tumor grade or invasiveness and immunohistochemical expression of these markers. Regarding gene expression, 50% of cases expressed CDH1, none expressed SNAI2, and 53.3% expressed NCAM1. There was no statistically significant relationship between tumor grade or invasiveness and gene expression of CDH1, SNAI2, and NCAM1. The absence of Slug overexpression and of E-cadherin and NCAM suppression suggests that expression of these markers is not associated with tumor invasiveness in GH-secreting pituitary adenomas.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Acromegalia/patologia , Adenoma/patologia , Caderinas/análise , Moléculas de Adesão de Célula Nervosa/análise , Fatores de Transcrição da Família Snail/análise , Acromegalia/genética , Acromegalia/metabolismo , Imuno-Histoquímica , Biomarcadores Tumorais/análise , Adenoma/genética , Adenoma/química , Expressão Gênica , Estudos Transversais , Gradação de Tumores
12.
Braz J Med Biol Res ; 51(2): e6808, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29267504

RESUMO

Pituitary adenomas account for 10-15% of primary intracranial tumors. Growth hormone (GH)-secreting adenomas account for 13% of all pituitary adenomas and cause acromegaly. These tumors can be aggressive, invade surrounding structures and are highly recurrent. The objective of this study was to evaluate E-cadherin, Slug and neural cell adhesion molecule (NCAM) expression in GH-secreting pituitary adenomas and its relationship to tumor invasiveness. A cross-sectional study of patients who underwent hypophysectomy due to GH-secreting pituitary adenoma from April 2007 to December 2014 was carried out. The medical records were reviewed to collect clinical data. Immediately after surgery, tumor samples were frozen in liquid nitrogen and stored in a biofreezer at -80°C for assessment of E-cadherin 1 (CDH1), SLUG (SNAI2), and NCAM (NCAM1) by real-time PCR. The samples were fixed in formalin and embedded in paraffin for immunohistochemical analysis of E-cadherin and NCAM. Thirty-five patients with acromegaly were included in the study. Of these, 65.7% had invasive tumors. Immunohistochemically, E-cadherin was expressed in 96.7% of patients, and NCAM in 80% of patients. There was no statistically significant relationship between tumor grade or invasiveness and immunohistochemical expression of these markers. Regarding gene expression, 50% of cases expressed CDH1, none expressed SNAI2, and 53.3% expressed NCAM1. There was no statistically significant relationship between tumor grade or invasiveness and gene expression of CDH1, SNAI2, and NCAM1. The absence of Slug overexpression and of E-cadherin and NCAM suppression suggests that expression of these markers is not associated with tumor invasiveness in GH-secreting pituitary adenomas.


Assuntos
Acromegalia/patologia , Adenoma/patologia , Caderinas/análise , Moléculas de Adesão de Célula Nervosa/análise , Neoplasias Hipofisárias/patologia , Fatores de Transcrição da Família Snail/análise , Acromegalia/genética , Acromegalia/metabolismo , Adenoma/química , Adenoma/genética , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/análise , Antígeno CD56/análise , Estudos Transversais , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Neoplasias Hipofisárias/química , Neoplasias Hipofisárias/genética , Reação em Cadeia da Polimerase em Tempo Real , Estatísticas não Paramétricas , Adulto Jovem
13.
AJNR Am J Neuroradiol ; 38(9): 1771-1775, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28684458

RESUMO

BACKGROUND AND PURPOSE: Intracranial aneurysm is a devastating disease of complex etiology that is not fully understood. The purpose of this study was to assess the implications of carotid siphon anatomy for the formation and development of intracranial aneurysms. MATERIALS AND METHODS: Between January 2007 and May 2015, lateral view digital subtraction angiographic images of 692 consecutive patients with intracranial aneurysms treated in our department of interventional neuroradiology were reviewed and had their angles measured. Data on the location, presentation, and size of the lesions were collected and evaluated by multivariate analysis in relation to the measured angles. RESULTS: Of 692 aneurysms, 225 (32.51%) ruptured and 467 (67.49%) unruptured, 218 (31.50%) were in the carotid siphon and 474 (68.50%) were distal to the siphon, and the mean aneurysm size was 7.99 ± 6.95 mm. Multivariate analysis showed an association between angles of >15.40° and rupture (P = .005), postsiphon location (P = .034), and aneurysm size of >1.001 mm (P = .015). Multivariate analysis also showed that every 1-year increase in patient age produced an increase of 1.002 mm in aneurysm size (P = .015). CONCLUSIONS: There was a significant independent direct relation of greater anterior knee angle with intracranial aneurysms located distal to the carotid siphon, larger aneurysms, and greater risk of rupture. These findings may be associated with the hemodynamic interactions of blood flow and the curvature of the carotid siphon.


Assuntos
Aneurisma Roto/patologia , Artéria Carótida Interna/anatomia & histologia , Aneurisma Intracraniano/patologia , Adulto , Idoso , Angiografia Digital , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
14.
Int J Oral Maxillofac Surg ; 46(11): 1387-1393, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28633929

RESUMO

The aim of this study was to assess the biomechanical stability of six different osteosynthesis methods after sagittal split osteotomy. Sixty polyurethane hemimandibles were divided into two groups, with six subgroups in each. After 10-mm advancement of the distal segment (group 1) and 10-mm advancement combined with 20° counterclockwise rotation (group 2), the bone segments were fixed using 2.0-mm plates/screws as follows: subgroup A, one conventional straight plate; subgroup B, two conventional straight plates; subgroup C, one conventional sagittal plate; subgroup D, one locking straight plate; subgroup E, two locking straight plates; subgroup F, one locking sagittal plate. The hemimandibles were tested for compressive strength by three-point biomechanical test, until there was 3mm of displacement between the segments. The fixations showed better performance in group 1 than in group 2 in all cases, with statistical significance for subgroups A, C, and D. In both groups, the use of two straight miniplates showed the most resistance, followed by the sagittal miniplates. However, in counterclockwise rotations, no statistically significant difference was found between two conventional straight plates and the sagittal locking plate. This study shows that the use of two plates is the form of fixation with the minimum displacement. If the clinician opts to use one plate, a sagittal plate is the best alternative.


Assuntos
Análise do Estresse Dentário/métodos , Fixadores Internos , Osteotomia Mandibular/métodos , Osteotomia Sagital do Ramo Mandibular , Fenômenos Biomecânicos , Humanos , Modelos Anatômicos , Poliuretanos
16.
J Laryngol Otol ; 129(11): 1133-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26399309

RESUMO

OBJECTIVE: To report a case of successful bone-anchored hearing aid implantation in an adult patient with type III osteogenesis imperfecta, which is commonly regarded as a contraindication to this procedure. CASE REPORT: A 45-year-old man with type III osteogenesis imperfecta presented with mixed hearing loss. There was a mild sensorineural component in both ears, with an air-bone gap between 45 and 50 dB HL. He was implanted with a bone-anchored hearing aid. The audiological outcome was good, with no complications and good implant stability (as measured by resonance frequency analysis). CONCLUSION: To our knowledge, this is the first recorded case of bone-anchored hearing aid implantation in a patient with osteogenesis imperfecta.


Assuntos
Auxiliares de Audição , Perda Auditiva Neurossensorial/reabilitação , Osteogênese Imperfeita/complicações , Âncoras de Sutura , Osso Temporal/cirurgia , Implante Coclear/métodos , Implantes Cocleares , Perda Auditiva Neurossensorial/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
17.
Artigo em Inglês | MEDLINE | ID: mdl-26066118

RESUMO

Stationary and time-dependent solutions of a nonlinear Kramers equation, as well as its associated nonlinear Fokker-Planck equations, are investigated within the context of Tsallis nonextensive statistical mechanics. Since no general analytical time-dependent solutions are found for such a nonlinear Kramers equation, an ansatz is considered and the corresponding asymptotic behavior is studied and compared with those known for the standard linear Kramers equation. The H-theorem is analyzed for this equation and its connection with Tsallis entropy is investigated. An application is discussed, namely the motion of Hydra cells in two-dimensional cellular aggregates, for which previous measurements have verified q-Gaussian distributions for velocity components and superdiffusion. The present analysis is in quantitative agreement with these experimental results.

18.
Rev. bras. plantas med ; 17(2): 297-304, Apr-Jun/2015. tab, graf
Artigo em Português | LILACS | ID: lil-746120

RESUMO

RESUMO: Plantas condimentares são amplamente utilizadas na culinária como alimento funcional. Pacientes hipertensos, que retiram o sal de cozinha (NaCl) de sua alimentação, relatam que os alimentos "perdem" o sabor. Visando alternativas para substituir o sal e melhorar a palatabilidade das preparações alimentares de pacientes hipertensos, o objetivo deste estudo foi desenvolver temperos à base de plantas medicinais e analisar os teores de compostos fenólicos, flavonoides e atividade antioxidante destes. Plantas (coentro, salsa, orégano, alecrim, manjericão, alho, cebola) cultivadas organicamente em Viçosa (MG) foram processadas e os temperos foram desenvolvidos a partir de combinação destas espécies, de acordo com teste aceitabilidade sensorial afetivo por meio de escala hedônica. Foram definidos três temperos, dos quais foram feitos extratos metanólicos por remaceração até esgotamento. Nas dosagens utilizou-se DPPH na avaliação da atividade antioxidante; reagente de Folin-Ciocalteu para compostos fenólicos e vanilina clorídrica para flavonoides. As análises foram feitas com quatro repetições e os resultados submetidos à análise de variância e teste de média a 5% de significância. Na aceitação subjetiva dos temperos a nota média foi 7,07±1,09 e 8,0±0,93 na ação afetiva como alimento. O teor mais elevado de compostos fenólicos foi no tempero 2 (alho, salsa e manjericão) (55,04±4,307 mg/mL), a maior ação antioxidante foi no tempero 1 (alho, cebola, coentro e orégano) nos tempos 0 (48,72%) e 30 minutos (78,37%). Os teores de flavonoides foram semelhantes nos 3 temperos. Todos os temperos tiveram boa aceitação por pacientes hipertensos e mostraram-se promissores na substituição dos condimentos convencionais.


ABSTRACT: Plant herbs are widely used in cooking as functional food. Hypertensive patients, who remove salt (NaCl) from their diets, report that the food "loses" flavor. Seeking alternatives to replace salt and improve the palatability of food preparations of hypertensive patients the aim of this study was to develop spices based on medicinal plants and analyze their contents of phenolic compounds, flavonoids and antioxidant activity. Plants (cilantro, parsley, oregano, rosemary, basil, garlic, onion) grown organically in the city of Viçosa (state of Mato Grosso, Brazil) were processed and the seasonings were developed from the combination of these species, according to the affective sensory acceptability test using the hedonic scale. Three spices were defined, and methanol extracts were made from them by maceration until exhaustion. In the dosages, we used DPPH to evaluate the antioxidant activity, Folin-Ciocalteu reagent for phenolic compounds and hydrochloric vanillin for flavonoids. The analyses were performed with four replicates and the results were subjected to analysis of variance and to a 5% significance test. In the subjective acceptance of the spices, the average score was 7.07 ± 1.09 and 8.0 ± 0.93 in the affective action as food. The highest content of phenolic compounds was for treatment 2 (garlic, parsley and basil) (55.04 ± 4.307 mg/mL) and the highest antioxidant activity was measured in treatment 1 (garlic, onion, cilantro and oregano) at 0 (48.72%) and 30 minutes (78.37%). The contents of flavonoids were similar in the three treatments. All spices were well accepted by the hypertensive patients and have shown to be a promising replacement of conventional spices.


Assuntos
Flavonoides/análise , Condimentos , Compostos Fenólicos/análise , Antioxidantes/análise , Plantas Medicinais/metabolismo , Análise de Variância , Alimento Funcional/análise , Hipertensão
19.
J Microbiol Methods ; 115: 1-5, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25966644

RESUMO

Transformation of non-competent Escherichia coli JM109 was accomplished using pUC19 as donor plasmid and sepiolite as the acicular material to promote cell piercing via application of friction with a polystyrene stick or a magnetic bar on the surface of a hydrogel containing agar. An automatic spreading setup was built with a conventional stirring plate and compared to manual spreading. Several parameters were optimized, namely, the agar content of the hydrogel (2%), concentration of cells (OD=1.3 corresponding to 1.4×10(9) bacterial cells/mL), concentration of sepiolite (0.01%), manual versus mechanical spreading (automatic spreading more consistent) and spreading time (30s). Efficiency values up to 4.1×10(4) CFU/µg pUC19 were obtained. The method proved to be suitable for a rapid and low cost transformation of non-competent E. coli JM109, where higher values of efficiency do not need to be attained.


Assuntos
Escherichia coli/genética , Técnicas de Transferência de Genes , Plasmídeos/genética , Transformação Bacteriana , Escherichia coli/metabolismo , Plasmídeos/metabolismo
20.
Clin Microbiol Infect ; 21(8): 799.e1-3, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25889358

RESUMO

Stool samples were obtained from healthy children and children with diarrhoea in Rio de Janeiro, Brazil, and analysed for aichivirus A and salivirus by reverse transcription PCR. Aichivirus A was detected in 5 (0.8%) and salivirus in 10 (1.7%) of the samples obtained from children with diarrhoea. None of the healthy children tested positive for these viruses. The results demonstrate that these viruses continuously circulate in the country, although at a low frequency.


Assuntos
Diarreia/virologia , Gastroenterite/virologia , Infecções por Picornaviridae/virologia , Picornaviridae/classificação , Picornaviridae/isolamento & purificação , Brasil/epidemiologia , Criança , Pré-Escolar , Diarreia/epidemiologia , Fezes/virologia , Feminino , Gastroenterite/epidemiologia , Humanos , Lactente , Masculino , Infecções por Picornaviridae/epidemiologia , Prevalência , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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