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1.
Molecules ; 28(8)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37110688

RESUMO

Interactions between polymers (P) and surfactants (S) in aqueous solution lead to interfacial and aggregation phenomena that are not only of great interest in physical chemistry but also important for many industrial applications, such as the development of detergents and fabric softeners. Here, we synthesized two ionic derivatives-sodium carboxymethylcellulose (NaCMC) and quaternized cellulose (QC)-from cellulose recycled from textile wastes and then explored the interactions of these polymers with assorted surfactants-cationic (CTAB, gemini), anionic (SDS, SDBS) and nonionic (TX-100)-commonly used in the textile industry. We obtained surface tension curves of the P/S mixtures by fixing the polymer concentration and then increasing the surfactant concentration. In mixtures where polymer and surfactant are oppositely charged (P-/S+ and P+/S-), a strong association is observed, and from the surface tension curves, we determined the critical aggregation concentration (cac) and critical micelle concentration in the presence of polymer (cmcp). For mixtures of similar charge (P+/S+ and P-/S-), virtually no interactions are observed, with the notable exception of the QC/CTAB system, which is much more surface active than the neat CTAB. We further investigated the effect of oppositely charged P/S mixtures on hydrophilicity by measuring the contact angles of aqueous droplets on a hydrophobic textile substrate. Significantly, both P-/S+ and P+/S- systems greatly enhance the hydrophilicity of the substrate at much lower surfactant concentrations than the surfactant alone (in particular in the QC/SDBS and QC/SDS systems).

2.
Neuropathology ; 36(1): 3-16, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26303046

RESUMO

Severe dengue disease is often associated with long-term neurological impairments, but it is unclear what mechanisms are associated with neurological sequelae. Previously, we demonstrated antibody-enhanced dengue disease (ADE) dengue in an immunocompetent mouse model with a dengue virus 2 (DENV2) antibody injection followed by DENV3 virus infection. Here we migrated this ADE model to Callithrix penicillata. To mimic human multiple infections of endemic zones where abundant vectors and multiple serotypes co-exist, three animals received weekly subcutaneous injections of DENV3 (genotype III)-infected supernatant of C6/36 cell cultures, followed 24 h later by anti-DENV2 antibody for 12 weeks. There were six control animals, two of which received weekly anti-DENV2 antibodies, and four further animals received no injections. After multiple infections, brain, liver, and spleen samples were collected and tissue was immunolabeled for DENV3 antigens, ionized calcium binding adapter molecule 1, Ki-67, TNFα. There were marked morphological changes in the microglial population of ADE monkeys characterized by more highly ramified microglial processes, higher numbers of trees and larger surface areas. These changes were associated with intense TNFα-positive immunolabeling. It is unclear why ADE should generate such microglial activation given that IgG does not cross the blood-brain barrier, but this study reveals that in ADE dengue therapy targeting the CNS host response is likely to be important.


Assuntos
Sistema Nervoso Central/patologia , Dengue/patologia , Inflamação/patologia , Animais , Anticorpos Antivirais/toxicidade , Barreira Hematoencefálica/patologia , Callithrix , Vírus da Dengue/imunologia , Hipocampo/patologia , Imuno-Histoquímica , Microglia/patologia , Fator de Necrose Tumoral alfa/metabolismo
3.
Plant Foods Hum Nutr ; 67(1): 82-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22173821

RESUMO

Many authors attribute the antioxidant activity of brewed coffee to its caffeine content. In addition, caffeine intake has been associated with increased performance during physical exercise. This study analyzed the in vivo effects of drinking caffeinated and decaffeinated instant coffee (8%, w/v) on oxidative stress and antioxidant enzyme activity in the anterior tibialis muscles of rats subjected to intense exercise. It was observed that exercise induced lipid peroxidation (estimated using malondialdehyde) and protein oxidation (evaluated by determining the formation of carbonyl groups) in the muscle (P < 0.05). Decaffeinated instant coffee and caffeine solution did not exhibit antioxidant activity in vivo. Caffeinated instant coffee beverage intake did not induce changes in superoxide dismutase and glutathione peroxidase activities but was able to diminish lipid and protein oxidation in the anterior tibialis muscles of rats after exercise (P < 0.05), contributing to a reduction in the oxidative stress triggered by exercise.


Assuntos
Antioxidantes/farmacologia , Cafeína/farmacologia , Café , Peroxidação de Lipídeos/efeitos dos fármacos , Músculos/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Teste de Esforço , Glutationa Peroxidase/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Masculino , Malondialdeído/metabolismo , Músculos/enzimologia , Oxirredução , Proteínas/química , Ratos , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo
4.
Waste Manag ; 153: 99-109, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36067549

RESUMO

Chemical recycling can be used to separate fibers that are constituents of different types of fabrics. This type of process can be considered one of the most effective forms of recycling, given that a large part of fabrics is made up of fiber mixtures. As part of an innovative circular strategy, the main goal of this work was to study the conditions for extracting cellulose from mixed textile wastes by acid hydrolysis and further transform it into cellulose derivatives, thus contributing to reduce such wastes and expanding the possible sources of cellulose. Our work covers a wide range of textile wastes and addresses the main technical challenges of this recycling methodology. The percentage of recovered cellulose powder varies between 65 and 88%. To evaluate the feasibility of using the extracted cellulose as raw material to produce cellulose derivatives, two strategies were applied: etherification to obtain sodium carboxymethylcellulose (with degree of substituion between 0.27 and 0.61) and esterification, to obtain cellulose acetate (with degree of substituion of 2.59). The cellulose derivatives obtained are very useful as additives in the textile industry, and hence the concept and practice of a circular economy are promoted.


Assuntos
Carboximetilcelulose Sódica , Reciclagem , Celulose , Hidrólise , Pós , Têxteis
5.
Environ Toxicol Pharmacol ; 87: 103703, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34265456

RESUMO

Potential endpoint biomarkers were evaluated in the assessment of exposure to triazoles, in the southern region of Minas Gerais, Brazil. Volunteers were divided into three groups: occupationally exposed and rural residents (n = 21), non-occupationally exposed and rural residents (n = 35) and non-occupationally exposed and urban residents (n = 30). Of all endpoints evaluated, plasma concentration of androstenedione (p < 0.001) and glycine-conjugated bile acids presented statistical differences in the three studied groups (p < 0.05). However, our findings concerning oxidative stress and testosterone levels, plus that related to unconjugated and taurine conjugated bile acids, suggested that more studies are necessary to evaluate their potential as biomarkers for triazole exposure, as statistical significance was not attained between the groups. Our human population data contributes to the development of triazole exposure risk assessment with respect to these potential effect biomarkers, in potentially vulnerable groups and individuals.


Assuntos
Disruptores Endócrinos , Fungicidas Industriais , Exposição Ocupacional , Triazóis , Adulto , Androstenodiona/sangue , Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/metabolismo , Monitoramento Biológico , Biomarcadores/sangue , Glicina/metabolismo , Humanos , Pessoa de Meia-Idade , Estresse Oxidativo , População Rural , Testosterona/sangue , População Urbana
6.
Int J Pharm ; 589: 119840, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32890657

RESUMO

Buclizine (BCZ) is a chiral synthetic piperazine derivative which has antihistaminic, anti-muscarinic and antiemetic properties, and has been reintroduced as an appetite stimulant, especially for pediatric patients. Structural information about this drug, as well as other buclizine crystalline forms (solvates, salts and co-crystals) including the BCZ free-base (BCZ-FB), is non-existent. Here, we present for the first time the crystal structure of the monohydrochloride monohydrate salt of BCZ (BCZHCl·H2O), and of its anhydrous form, BCZHCl. Interestingly, BCZHCl·H2O was obtained by recrystallization from the raw material (BCZH2Cl2) in ethanol:water solution showing that BCZ anhydrous dihydrochloride salt changes easily to a monohydrochloride monohydrate salt modification, which raise concerns about formulation quality control. BCZHCl·H2O and BCZHCl crystallize in the orthorhombic space groups (Pna21 and Pca21) belonging to the mm2 point group and are thus classified as non-centrosymmetric achiral structures (NA). Intuitively, we expect these salts to crystallize in a space group with a center of symmetry, since less than 5% of the known racemic compounds crystallize in the NA type. The crystal structures of BCZH2Cl2 and BCZ-FB were not determined, but their existence was verified by other techniques (chloride ion analysis, PXRD, HPLC, FT-IR, DSC, TGA) and by comparison of the obtained results with those found for BCZHCl. Additionally, we have also performed an evaluation of the equilibrium solubility (at six different aqueous media) and the dissolution profile of the BCZHCl salt compared to the raw material and BCZ-FB. Different equilibrium solubility values were found comparing the three forms in acidic and neutral pH ranges and all of them were insoluble at pH > 7.0. Moreover, tablets prepared with BCZH2Cl2, BCZHCl or BCZ-FB show significant differences in terms of dissolution profile.


Assuntos
Preparações Farmacêuticas , Piperazinas , Criança , Humanos , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Artigo em Inglês | MEDLINE | ID: mdl-30369957

RESUMO

The oil obtained from baru (Dipteryx alata Vog.) almonds exhibits high energy value and is reported in popular medicine for the treatment of rheumatic diseases and reproductive disturbances. Although baru oil is used in domestic cuisine, the chemical characterization of this oil and its effects on lipid metabolism are still poorly understood. Therefore, this study evaluated the fatty acid (FA) profile and the effects of baru oil on liver and aorta in a murine model of dyslipidemia. The chromatographic profile of baru oil showed high levels of unsaturated FAs, especially oleic acid. Saturated FAs, such as palmitic and lignoceric acids, were found in lower amounts. Hypercholesterolemia was induced in male Wistar rats by daily administration of a lipid emulsion by gavage for 15 weeks. Biochemical and histopathological analysis were performed on serum, aorta, and liver. The results demonstrated that animals developed marked hypercholesterolemia, liver steatosis, and increased lipid peroxidation in the aorta. Treatment with baru oil attenuated lipid peroxidation and drastically reduced liver damage, especially ballooning degeneration and steatosis. By restricting vascular and hepatic injury, this oil showed potential applicability as a functional food, reinforcing its use in popular medicine and domestic cuisine.

8.
Int J Pharm ; 553(1-2): 272-280, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30359686

RESUMO

Glimepiride (GLIM) is used as an oral antihyperglycemic agent for treatment of type 2 diabetes. The drug presents two polymorphic forms (GLIM form I and GLIM form II) described in the literature, and according to in vitro data, GLIM form II is about 3.5 times more soluble and releases 2 times the drug amount than GLIM form I in the physiological pH range. Considering the literature in vitro data and that the diabetes treatment demands glycemic control, avoiding abrupt fluctuations in the blood glucose levels, this work aimed to study the impact of GLIM polymorphism in the in vivo performance of GLIM solid oral dosages. For this, hard gelatin capsules with GLIM form I or II were prepared and orally administered in rats. After that, pharmacokinetic studies were performed by sampling animal blood at different times, and biochemical parameters (pharmacodynamic), such as glucose and insulin, were also evaluated. Our results showed that the in vitro data corroborate with our in vivo assays. GLIM form II provided higher plasma concentration of drug than form I (at baseline up to approximately 200 min after oral administration) and, consequently, increased insulin release and reduced levels of glucose, showing good correlation between pharmacokinetic and pharmacodynamics assays. Thus, this study demonstrated that GLIM polymorphs in oral dosages might alter the drug efficacy, which may expose the patients to risks, such as hypoglycemia.


Assuntos
Glicemia/efeitos dos fármacos , Hipoglicemiantes/química , Insulina/sangue , Compostos de Sulfonilureia/química , Administração Oral , Animais , Cápsulas , Cristalização , Gelatina , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/farmacologia , Masculino , Ratos , Ratos Wistar , Solubilidade , Compostos de Sulfonilureia/farmacocinética , Compostos de Sulfonilureia/farmacologia
9.
Environ Toxicol Pharmacol ; 55: 99-106, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28843102

RESUMO

The aim of the study was to assess of occupational exposure to pesticides in rural workers using genotoxicity test, bioindicators and clinical evaluation. Blood, urine and buccal samples from persons, rural workers exposed to a complex mixture of pesticides with organophosphates (n=94) and without organophosphates (n=94) were collected to compare the activities of cholinesterases, the levels of urinary dialkyl phosphates, genotoxicity data, from a cytome assay. Biomarkers were analysed by traditional/published methods Control group consisted of 50 other persons, non- occupationally exposed to pesticides from the city of Alfenas, Minas Gerais, Brazil. All subjects underwent a clinical evaluation. In the group exposed to organophosphates, the activity of acetylcholinesterase, butyrylcholinesterase and total cholinesterase was lower by 63.8%, 12.8%, and 14.8%, respectively, and 92.6% of the group had dialkyl phosphates present in their urine. The cytome assay was used to measure biomarkers of DNA damage (micronuclei and/or elimination of nuclear material by budding), cytokinetic defects (binucleated cells), and proliferative potential (basal cell) and/or cell death (condensed chromatin, karyorrhectic, pyknotic, and karyolytic cells). The group exposed to organophosphates showed significant changes in all these parameters compared to the control group and showed significant changes in budding, condensed chromatin and karyolytic cells compared with the group non-exposed to organophosphates. Data from the clinical evaluation showed significant changes in the central nervous, respiratory and auditory systems. The studied biomarkers are able to distinguish occupational and environmental exposure to pesticides and the data showed hazardous exposure to organophosphates and afforded valuable data to estimate the risk to cancer development.


Assuntos
Alcanos/análise , Colinesterases/metabolismo , Exposição Ocupacional/efeitos adversos , Organofosfatos/efeitos adversos , Praguicidas/efeitos adversos , Adulto , Alcanos/sangue , Alcanos/urina , Sangue/efeitos dos fármacos , Sangue/metabolismo , Brasil , Dano ao DNA , Feminino , Humanos , Masculino , Testes para Micronúcleos , Pessoa de Meia-Idade , Boca/efeitos dos fármacos , Boca/metabolismo , Testes de Mutagenicidade , População Rural , Urina/química
10.
Braz. J. Pharm. Sci. (Online) ; 58: e19562, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1394045

RESUMO

Abstract This study aimed to evaluate the antioxidant potential of the Coffea arabica Lineu (L.) leaf extract and its effects on platelet aggregation of dyslipidemic rats. The extract was obtained by the percolation of C. arabica L. leaves in hydroethanolic solution 70% (v/v). The mass spectrometry FIA-ESI-MS² suggested the presence of chlorogenic acid, rutin acid, and quinic acid. The DPPH• radicals scavenging capacity was demonstrated (IC50 = 0.06 mg/mL). The extract was administered to rats by gavage (300 mg/kg/day) for 56 days. Dyslipidemia was induced by administering Triton WR-1339 (300 mg/kg body weight) on the 54th day. On day 56, blood was collected by puncturing the abdominal aorta artery and the aortic artery was removed. Lipid profile, markers of renal and hepatic injury, lipid peroxidation, and platelet aggregation tests were carried out. The ingestion of extract reduced the lipid peroxidation (aorta and plasma) and platelet aggregation in dyslipidemic rats. The extract did not affect markers of renal and hepatic function as analyzed in this study, suggesting neither impaired liver nor kidney function in these animals. Therefore, our results demonstrate that the extract of leaves of C. arabica L. show antioxidant potential in vitro and in vivo as well as anti-platelet aggregation in dyslipidemic animals


Assuntos
Animais , Masculino , Feminino , Ratos , Extratos Vegetais/análise , Folhas de Planta/classificação , Coffea/efeitos adversos , Dislipidemias/tratamento farmacológico , Espectrometria de Massas/métodos , Plaquetas/classificação , Agregação Plaquetária , Antioxidantes/administração & dosagem
11.
Arq Neuropsiquiatr ; 64(3A): 672-5, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17119817

RESUMO

We report on a 49 year old man with impacted cisterna magna without the presence of syringohydromyelie (SM). The clinical picture was characterized by spastic paraparesis. Magnetic resonance imaging depicted a cisterna magna filled by the cerebellar tonsils. Six months after osteodural-neural decompression of the posterior fossa there was resolution of neurological symptoms and signs with the exception of hyperactive patellar and Achilles reflexes.


Assuntos
Malformação de Arnold-Chiari/diagnóstico , Cisterna Magna , Paraparesia Espástica/diagnóstico , Malformação de Arnold-Chiari/complicações , Malformação de Arnold-Chiari/cirurgia , Descompressão Cirúrgica , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Paraparesia Espástica/etiologia , Paraparesia Espástica/cirurgia
12.
Rev. ciênc. farm. básica apl ; 42: 1-14, 20210101.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1177731

RESUMO

Objectives: The study aimed to determine the effect of coffee intake on AGEs formation and platelet aggregation in diabetic Wistar rats. Methods: Coffee powder samples were used to prepare a 10% beverage. Diabetes mellitus was induced in the animals by administering 2% alloxan. All animal experiments were approved by the ethics committee for animal experiments under N°. 420/2012 and 536/2013. Diabetic and non-diabetic rats were divided into 6 groups treated and untreated with coffee (7.2 mL/Kg body weight) and aminoguanidine (AGE inhibiting agent) (100 mg/Kg body weight) for 50 days. After 50 days, the animals were fasted for 12 h and anesthetized (40 mg/Kg sodium pentobarbital) intraperitoneally. Blood samples were collected from the abdominal artery puncture. Hematological parameters (red cells, hemoglobin, hematocrit and leukocyte) and glycemic and HbA1c levels were measured. AGEs quantification (spectrofluorometric method) and the platelet aggregation test (aggregation of cuvettes in a four-channel platelet aggregometer) were also conducted. The rats' renal function was evaluated by measuring serum urea and creatinine. Results: Data showed that coffee intake had no effect on the hematological parameters. Fasting glucose and HbA1c dosage were significantly higher in diabetic animals compared to non-diabetic animals (confirmed the effectiveness of inducing and maintaining diabetic status). Results showed that coffee reduced AGE formation and platelet aggregation in our animal model, not altering the animals' renal function. Conclusions: These results suggest beneficial effects on vasculopathy, a common complication in diabetic patients.

13.
Rev. ciênc. farm. básica apl ; 41: [13], 01/01/2020.
Artigo em Inglês | LILACS | ID: biblio-1147064

RESUMO

The present study analyzed the in vivo effects of drinking caffeinated and decaffeinated instant coffee (8% w/v) by adult male Wistar rats submitted to high-intensity exercises. The parameters used in the evaluation were the determination of the activities of NADPH oxidase, myeloperoxidase and other antioxidant enzymes present in neutrophils of rats. It was observed that exercise-induced superoxide anion production depends on the NADPH oxidase activity (estimated by the cytochrome C reduction test) in peritoneal neutrophils (p < 0.05). The intake of caffeinated and decaffeinated instant coffee beverages and of a caffeine solution to 1.67% did not induced changes in the activities of the enzymes myeloperoxidase, superoxide dismutase and glutathione peroxidase (p < 0.05). But consumption of caffeinated instant coffee drink prevented an increase in NADPH oxidase-mediated superoxide production induced by highly intense exercise in rat neutrophils. While the decaffeinated instant coffee drink or caffeine solution alone did not affect NADPH oxidase-mediated superoxide production. We suggest that this activity is associated with the chemical composition and concentration of phenolic compounds and other antioxidant substances formed during roasting. From the obtained results, it was concluded that moderate intake of caffeinated instant coffee (equivalent to a daily human consumption of 4 50-mLcups of coffee) may have beneficial effects on health, contributing to a reduction in superoxide anion generation. Therefore, more research must be conducted to elucidate the mechanism of action of caffeinated coffee on NADPH oxidase in neutrophils.


Assuntos
Análise de Mediação
14.
PLoS One ; 8(8): e72719, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23977346

RESUMO

Dyslexic children, besides difficulties in mastering literacy, also show poor postural control that might be related to how sensory cues coming from different sensory channels are integrated into proper motor activity. Therefore, the aim of this study was to examine the relationship between sensory information and body sway, with visual and somatosensory information manipulated independent and concurrently, in dyslexic children. Thirty dyslexic and 30 non-dyslexic children were asked to stand as still as possible inside of a moving room either with eyes closed or open and either lightly touching a moveable surface or not for 60 seconds under five experimental conditions: (1) no vision and no touch; (2) moving room; (3) moving bar; (4) moving room and stationary touch; and (5) stationary room and moving bar. Body sway magnitude and the relationship between room/bar movement and body sway were examined. Results showed that dyslexic children swayed more than non-dyslexic children in all sensory condition. Moreover, in those trials with conflicting vision and touch manipulation, dyslexic children swayed less coherent with the stimulus manipulation compared to non-dyslexic children. Finally, dyslexic children showed higher body sway variability and applied higher force while touching the bar compared to non-dyslexic children. Based upon these results, we can suggest that dyslexic children are able to use visual and somatosensory information to control their posture and use the same underlying neural control processes as non-dyslexic children. However, dyslexic children show poorer performance and more variability while relating visual and somatosensory information and motor action even during a task that does not require an active cognitive and motor involvement. Further, in sensory conflict conditions, dyslexic children showed less coherent and more variable body sway. These results suggest that dyslexic children have difficulties in multisensory integration because they may suffer from integrating sensory cues coming from multiple sources.


Assuntos
Dislexia/fisiopatologia , Sensação/fisiologia , Filtro Sensorial/fisiologia , Criança , Feminino , Dedos , Humanos , Masculino , Postura/fisiologia , Fatores de Tempo
15.
J Med Microbiol ; 62(Pt 9): 1326-1331, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23741024

RESUMO

One hundred and six nalidixic acid-resistant Enterobacteriaceae isolates from two Brazilian hospitals isolated from June to October 2010 were evaluated to characterize the co-existence of plasmid-mediated quinolone resistant (PMQR) and extended-spectrum ß-lactamase (ESBL) determinants. The qnr genetic environment was determined by PCR and sequencing. Conjugation and hybridization experiments determined whether qnr-carrying plasmids were self-transferable. The aac(6')-Ib-cr and qepA genes were also screened. Thirteen qnr-like genes (12.3 %) were identified, with qnrB1 the most common, followed by qnrS1, qnrB2 and qnrB19. No qnrA, qnrC, qnrD or qepA determinant was detected. All qnr-positive strains possessed chromosomal substitutions in gyrase- and topoisomerase-encoding genes and four harboured a aac(6')-Ib-cr gene. The co-production of blaCTX-M was observed in ten qnr-positive strains. These results indicate the dissemination of PMQR genes shown in clinical isolates from Brazil, and their co-existence with ESBL genes emphasizes the complexity of plasmid-mediated resistance determinants among Enterobacteriaceae.


Assuntos
Farmacorresistência Bacteriana , Enterobacteriaceae/enzimologia , Ácido Nalidíxico/farmacologia , Plasmídeos/genética , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Brasil , Cefotaxima/farmacologia , Cromossomos Bacterianos/genética , Cromossomos Bacterianos/metabolismo , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Genes Bacterianos , Testes de Sensibilidade Microbiana , Mutação , Plasmídeos/metabolismo , Infecção da Ferida Cirúrgica/microbiologia , Urina/microbiologia , beta-Lactamases/genética
17.
Neurosci Lett ; 492(1): 29-32, 2011 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-21276829

RESUMO

This study investigated the influence of gymnastics training on the postural control of children with and without the use of visual information. Two age groups, aged 5-7 and 9-11 years old, of gymnasts and nongymnasts were asked to maintain an upright and quiet stance on a force platform with eyes open (EO) and eyes closed (EC) for 30s. Area of the stabilogram (AOS) and mean velocity of the center of pressure (COP) in anterior-posterior (AP) and medial-lateral (ML) directions were calculated and used to investigate the effects of gymnastics training, age, and visual information. Younger gymnasts presented greater postural control compared to younger nongymnasts while visual information did not improve postural control in younger nongymnasts. Younger gymnasts displayed improved postural control with EO compared to EC. The mean velocity of the COP in the ML direction was: less for younger gymnasts than younger nongymnasts with EO. These results suggest that gymnastics training promotes improvements in postural control of younger children only, which results from their use of visual information when available.


Assuntos
Ginástica , Postura , Desempenho Psicomotor , Fatores Etários , Criança , Pré-Escolar , Feminino , Humanos , Percepção Visual
18.
Res Dev Disabil ; 32(5): 1814-21, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21498044

RESUMO

Difficulty with literacy acquisition is only one of the symptoms of developmental dyslexia. Dyslexic children also show poor motor coordination and postural control. Those problems could be associated with automaticity, i.e., difficulty in performing a task without dispending a fair amount of conscious efforts. If this is the case, dyslexic children would show difficulties in using "unperceived" sensory cues to control body sway. Therefore, the aim of the study was to examine postural control performance and the coupling between visual information and body sway in dyslexic children. Ten dyslexic children and 10 non-dyslexic children stood upright inside a moving room that remained stationary or oscillated back and forward at frequencies of 0.2 or 0.5 Hz. Body sway magnitude and the relationship between the room's movement and body sway were examined. The results indicated that dyslexic children oscillated more than non-dyslexic children in both stationary and oscillating conditions. Visual manipulation induced body sway in all children but the coupling between visual information and body sway was weaker and more variable in dyslexic children. Based upon these results, we can suggest that dyslexic children use visual information to postural control with the same underlying processes as non-dyslexic children; however, dyslexic children show poorer performance and more variability while relating visual information and motor action even in a task that does not require an active cognitive and conscious motor involvement, which may be a further evidence of automaticity problem.


Assuntos
Dislexia/fisiopatologia , Equilíbrio Postural/fisiologia , Postura/fisiologia , Desempenho Psicomotor/fisiologia , Criança , Estado de Consciência/fisiologia , Humanos , Sensação/fisiologia , Acuidade Visual/fisiologia , Volição/fisiologia
19.
Rev. bras. ciênc. esporte ; 33(3): 747-760, jul.-set. 2011. graf, tab
Artigo em Português | LILACS | ID: lil-611262

RESUMO

O objetivo deste estudo foi investigar o desempenho e a contribuição da informação visual no controle postural de crianças praticantes e não praticantes de ginástica artística (GA). Quarenta e três meninas, 23 praticantes de GA e 20 não praticantes de GA, idade 5 a 7 e 9 a 11 anos, permaneceram em pé sobre uma plataforma de força em três bases de apoio: bipodal, semi-tandem stance e base reduzida, com olhos abertos e com olhos fechados. A área de deslocamento do centro de pressão e o índice de contribuição visual foram calculados. Os resultados indicaram que a prática de GA melhora o controle postural de crianças nos anos iniciais de desenvolvimento. Ainda, crianças praticantes de GA utilizam melhor informação visual que crianças não praticantes de GA para manter a postura ereta mais estável.


The purpose of this study was to investigate postural control and the importance of visual information in gymnastics and non-gymnastics children. Forty-three female children, 23 gymnastics and 20 non-gymnastics, age 5 to 7 and 9 to 11 years, stood upright on a force platform in bipodal, semi-tandem, and reduced bases, with and without vision. The area of center of pressure oscillation and the visual contribution index were calculated. The results indicated that practice of gymnastic improves postural control in younger children. Finally, gymnastic children use more properly visual information than non-gymnastic children in order to maintain the upright stance more steadily.


El objetivo de este trabajo fue investigar el desempeño y la contribución de la información visual en el control postural en niños practicantes e no practicantes de gimnasia artística (GA). Cuarenta y tres niñas, 23 practicantes de GA y 20 no practicantes de GA, de 5 a 7 y de 9 a 11 años de edad, permanecieron en pie sobre una plataforma de fuerza con tres bases de apoyo: bipodal, semi-tandem stance y base reducida, con los ojos abiertos y con los ojos cerrados. El área de desplazamiento del centro de presión y el índice de contribución visual fueron calculados. Los resultados indicaron que la práctica de GA mejora el control postural de los niños en los primeros años de desarrollo evolutivo. Los niños practicantes de GA utilizan mejor la información visual para mantener la postura erecta más estable que los niños no practicantes de GA.

20.
Arq. neuropsiquiatr ; 64(3a): 672-675, set. 2006. ilus
Artigo em Inglês, Português | LILACS | ID: lil-435611

RESUMO

We report on a 49 year old man with impacted cisterna magna without the presence of syringohydromyelie (SM). The clinical picture was characterized by spastic paraparesis. Magnetic resonance imaging depicted a cisterna magna filled by the cerebellar tonsils. Six months after osteodural-neural decompression of the posterior fossa there was resolution of neurological symptoms and signs with the exception of hyperactive patellar and Achilles reflexes.


Hans Chiari (1891, 1895) descreveu 4 tipos de anomalias cerebelares que, ulteriormente, foram denominadas de malformação de Chiari (MC). Iskandar et al. (1998) relataram 5 casos de hidrosiringomielia (SM) sem herniação rombencefálica, nos quais as tonsilas cerebelares preenchiam a cisterna magna. Todos os casos melhoraram após a descompressão da fossa posterior com redução do tamanho da cavidade siringomiélica. Relatamos o caso de paciente de 49 anos com cisterna magna impactada sem a presença de siringo-hidromielia (SM). O quadro clínico caracterizava-se por paraparesia espástica. A ressonância magnética evidenciou a cisterna magna preenchida pelas tonsilas cerebelares. Seis meses após a descompressão osteodural-neural da fossa posterior, houve resolução dos sintomas e sinais neurológicos, com exceção da hiperatividade dos reflexos patelares e aquileus.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Malformação de Arnold-Chiari/diagnóstico , Cisterna Magna , Paraparesia Espástica/diagnóstico , Malformação de Arnold-Chiari/complicações , Malformação de Arnold-Chiari/cirurgia , Descompressão Cirúrgica , Imageamento por Ressonância Magnética , Paraparesia Espástica/etiologia , Paraparesia Espástica/cirurgia
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