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1.
Childs Nerv Syst ; 37(1): 211-215, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32661646

RESUMO

BACKGROUND: Acute flaccid myelitis (AFM) syndrome consists of loss of lower motor neurons following a viral infection, with preserved sensory function. It usually affects the upper limbs asymmetrically, with proximal more than distal muscle involvement. METHODS: Five cases were surgically treated with nerve transfers: spinal accessory to suprascapular nerve transfer (4 patients), branch of radial nerve to axillary nerve transfer (Somsak's procedure) (2 patients), and transfer of a fascicle of the ulnar nerve to the motor branch to the biceps (Oberlin's procedure) (1 patient). RESULTS: Motor improvement was seen in three cases. Widespread motor involvement was associated with poor outcome. CONCLUSION: This small series of cases reinforces that nerve transfers are a reliable option for treatment of selected children with AFM.


Assuntos
Viroses do Sistema Nervoso Central , Mielite , Transferência de Nervo , Doenças Neuromusculares , Criança , Humanos , Mielite/cirurgia , Nervo Ulnar
2.
Sci Rep ; 9(1): 4708, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30886193

RESUMO

Several experimental works currently demonstrate that metallic nano-oxides and carbon nanomaterials expected to be diamagnets, in fact, behave as ferromagnets at room temperature. More than scientifically intriguing, this unconventional and unexpected ferromagnetism pave the way for innovation products and novel nanotechnological applications, gathering the magnetism to interesting functionalities of these nanomaterials. Here, we investigate the non-conventional ferromagnetism observed at high temperatures in nanocrystalline cerium dioxide (CeO2or nanoceria) thin films that are optically transparent to visible light. Nanoceria exhibits several concrete applications in catalytic processes, photovoltaic cells, solid-state fuel cells, among others, which are mostly due to natural presence of oxygen vacancies and easy migration of the oxygen through the structure. The ferromagnetism in non-stoichiometric nanocrystaline ceria can be consistently described by ab initio electronic structure calculations, which support that oxygen vacancies cause the formation of magnetic moments and can provide a robust interconnectivity within magnetic polarons theoretical framework. Additionally, we present a conceptual model to account the oxygen transport to the non-conventional ferromagnetism at temperatures well above room temperature. The approach is complementary to the thermally-activated effective transfers of charge and spin around oxygen vacancy centers.

3.
J Phys Condens Matter ; 22(21): 216004, 2010 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-21393730

RESUMO

We studied the structural, chemical and magnetic properties of non-doped ceria (CeO(2)) thin films electrodeposited on silicon substrates. Experimental results confirm that the observed room temperature ferromagnetism is driven by both cerium and oxygen vacancies. We investigated ceria films presenting vacancy concentrations well above the percolation limit. Irradiation experiments with neon ions were employed to generate highly oxygen defective CeO(2-δ) structures. X-ray photoelectron spectroscopy and x-ray absorption near-edge structure spectroscopy were used to estimate the concentration of Ce(3+) sites in the films, which can reach up to 50% of Ce(3+) replacing Ce(4+), compared to a stoichiometric CeO(2) structure. Despite the increment of structural disorder, we observe that the saturation magnetization continuously increases with Ce(3+) concentration. Our experiments demonstrate that the ferromagnetism observed in ceria thin films, highly disordered and oxygen-deficient, preserving the fluorite-type structure only in a nanometer scale, remains intrinsically stable at room temperature.

4.
Photochem Photobiol ; 84(3): 627-31, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18282181

RESUMO

We report an experimental and theoretical study of magnetic properties of synthetic eumelanin. The magnetization curves are determined by using both a vibrating sample magnetometer and a superconducting quantum interferometer device in an extended range of magnetic fields ranging from -10 kOe to 10 kOe at different temperatures. We find that the eumelanin magnetization can be qualitatively explained in terms of a simple model of dipolar spheres with an intrinsic magnetic moment. The latter one is experimentally measured by using X-band electron paramagnetic resonance. Our findings indicate that synthetic melanins are superparamagnetic.


Assuntos
Magnetismo , Melaninas/química , Simulação por Computador , Espectroscopia de Ressonância de Spin Eletrônica , Melaninas/síntese química , Método de Monte Carlo , Temperatura
5.
Phytomedicine ; 14(6): 377-80, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17140782

RESUMO

The present study was designated to evaluate the antileishmanial activity of acid and basic fractions that were obtained after acid-basic extraction, from ethanolic 70% crude extract and pure compounds from the stem bark of Aspidosperma ramiflorum. The basic alkaloidal fraction presented a good activity against the extracellular form (promastigotes) of Leishmania (L.) amazonensis (LD(50) value<47 microg/ml). Based on these findings, the basic fraction was fractionated on silica gel column chromatography in a bioassay-guided fractionation affording individual purified ramiflorines A and B. Both ramiflorines A and B showed significant activity against Leishmania (L.) amazonensis (LD(50) values of 16.3+/-1.6 microg/ml and 4.9+/-0.9 microg/ml, respectively). Our results are promising, showing that these compounds are biologically active against Gram-positive bacteria.


Assuntos
Antiprotozoários/farmacologia , Aspidosperma/química , Alcaloides Indólicos/farmacologia , Leishmania/efeitos dos fármacos , Animais , Antiprotozoários/química , Alcaloides Indólicos/química , Conformação Molecular , Fitoterapia , Casca de Planta/química , Caules de Planta/química
6.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;39(3): 387-391, Mar. 2006. ilus, graf
Artigo em Inglês | LILACS | ID: lil-421371

RESUMO

We evaluated the antibacterial activities of the crude methanol extract, fractions (I-V) obtained after acid-base extraction and pure compounds from the stem bark of Aspidosperma ramiflorum. The minimum inhibitory concentration (MIC) was determined by the microdilution technique in Mueller-Hinton broth. Inoculates were prepared in this medium from 24-h broth cultures of bacteria (10(7) CFU/mL). Microtiter plates were incubated at 37°C and the MICs were recorded after 24 h of incubation. Two susceptibility endpoints were recorded for each isolate. The crude methanol extract presented moderate activity against the Gram-positive bacteria B. subtilis (MIC = 250 µg/mL) and S. aureus (MIC = 500 µg/mL), and was inactive against the Gram-negative bacteria E. coli and P. aeruginosa (MIC > 1000 µg/mL). Fractions I and II were inactive against standard strains at concentrations of <=1000 µg/mL and fraction III displayed moderate antibacterial activity against B. subtilis (MIC = 500 µg/mL) and S. aureus (MIC = 250 µg/mL). Fraction IV showed high activity against B. subtilis and S. aureus (MIC = 15.6 µg/mL) and moderate activity against E. coli and P. aeruginosa (MIC = 250 µg/mL). Fraction V presented high activity against B. subtilis (MIC = 15.6 µg/mL) and S. aureus (MIC = 31.3 µg/mL) and was inactive against Gram-negative bacteria (MIC > 1000 µg/mL). Fractions III, IV and V were then submitted to bioassay-guided fractionation by silica gel column chromatography, yielding individual purified ramiflorines A and B. Both ramiflorines showed significant activity against S. aureus (MIC = 25 µg/mL) and E. faecalis (MIC = 50 µg/mL), with EC50 of 8 and 2.5 µg/mL for ramiflorines A and B, respectively, against S. aureus. These results are promising, showing that these compounds are biologically active against Gram-positive bacteria.


Assuntos
Antibacterianos/farmacologia , Aspidosperma/química , Alcaloides Indólicos/farmacologia , Antibacterianos/química , Bacillus subtilis/efeitos dos fármacos , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Alcaloides Indólicos/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos
7.
Sci. agric ; 56(1)1999.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1495745

RESUMO

The main objective of this work was to study the applicability of the method of Acton to estimate the lactose concentration in Minas Frescal cheese. Recovery experiments were carried out, with recoveries for lactose ranging from 99.1% to 103.7%., for samples containing up to 40 FONT FACE="Symbol">m /font>g lactose/ml. Cheese samples were purchased randomly in Piracicaba, SP, Brasil with two days of shelf life, from three batches, with three samples per batch. Lactose was determined in the same day and its concentration varied from 2.36% to 2.47% for batch 1; 2.58% to 3.03% for batch 2; and from 2.19% to 2.48% for batch 3. A high uniformity was observed among batches, with little variation among samples. All values were within the range tipically found for this kind of cheese.


O principal objetivo deste trabalho foi verificar a aplicabilidade do método de Acton na determinação de lactose em queijo tipo Minas Frescal e, para isso estudou-se a porcentagem de recuperação de lactose adicionada a amostras dos queijos, em diferentes situações. As recuperações variam de 99,1% e 103,7% , e os melhores resultados em torno de 100%, obtidos para as amostras preparadas contendo até 40 FONT FACE="Symbol">m /font>g de lactose / ml. Os queijos tipo Minas Frescal, de três lotes diferentes com três queijos por lote, foram adquiridos no comércio de Piracicaba, SP aos dois dias de fabricação e nesse mesmo dia, analisados para o teor de lactose. Os resultados variaram de 2,36% a 2,47% no lote 1; 2,68% a 3,03% no lote 2 e 2,19% a 2,48% no lote 3, mostrando, assim, boa uniformidade dentro dos lotes e pequena variação entre estes, mas, todos os valores apresentaram-se dentro das faixas comumente encontradas para este tipo de queijo.

8.
Sci. agric. ; 56(1)1999.
Artigo em Português | VETINDEX | ID: vti-439204

RESUMO

The main objective of this work was to study the applicability of the method of Acton to estimate the lactose concentration in Minas Frescal cheese. Recovery experiments were carried out, with recoveries for lactose ranging from 99.1% to 103.7%., for samples containing up to 40 FONT FACE="Symbol">m /font>g lactose/ml. Cheese samples were purchased randomly in Piracicaba, SP, Brasil with two days of shelf life, from three batches, with three samples per batch. Lactose was determined in the same day and its concentration varied from 2.36% to 2.47% for batch 1; 2.58% to 3.03% for batch 2; and from 2.19% to 2.48% for batch 3. A high uniformity was observed among batches, with little variation among samples. All values were within the range tipically found for this kind of cheese.


O principal objetivo deste trabalho foi verificar a aplicabilidade do método de Acton na determinação de lactose em queijo tipo Minas Frescal e, para isso estudou-se a porcentagem de recuperação de lactose adicionada a amostras dos queijos, em diferentes situações. As recuperações variam de 99,1% e 103,7% , e os melhores resultados em torno de 100%, obtidos para as amostras preparadas contendo até 40 FONT FACE="Symbol">m /font>g de lactose / ml. Os queijos tipo Minas Frescal, de três lotes diferentes com três queijos por lote, foram adquiridos no comércio de Piracicaba, SP aos dois dias de fabricação e nesse mesmo dia, analisados para o teor de lactose. Os resultados variaram de 2,36% a 2,47% no lote 1; 2,68% a 3,03% no lote 2 e 2,19% a 2,48% no lote 3, mostrando, assim, boa uniformidade dentro dos lotes e pequena variação entre estes, mas, todos os valores apresentaram-se dentro das faixas comumente encontradas para este tipo de queijo.

9.
Sci. agric ; 50(3)1993.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1495287

RESUMO

The chemical and nutritional compositions of cheese and yogurt made from buffalo and cow milk were compared. The following conclusions were obtained: mozzarella type cheese and yogurt made from buffalo milk exhibited higher content of protein, fat, minerals, calcium and phosphorus when compared to those made from cow milk; in vitro digestibility tests of mozzarella type cheese and yogurt made from buffalo milk were similar to those of cow milk, indicantig suitable digestibility levels for human consumption.


O presente trabalho teve por objetivo verificar a composição química e nutricional do queijo e iogurte elaborados com leite de búfala e comparados com aqueles elaborados com leite de vaca. Dos resultados obtidos foram obtidas as seguintes conclusões: o queijo tipo mozzarella e o iogurte elaborado com leite de búfala apresentaram níveis superiores em proteína, gordura, cinzas, cálcio e fósforo, estando relacionados com a composição química inicial do leite. Os níveis de digestibilidade in vitro dos queijos tipo mozzarella e iogurte de leite de búfala apresentaram resultados semelhantes aos elaborados com leite de vaca, indicando níveis adequados de digestibilidade para consumo humano.

10.
Sci. agric. ; 50(3)1993.
Artigo em Português | VETINDEX | ID: vti-438760

RESUMO

The chemical and nutritional compositions of cheese and yogurt made from buffalo and cow milk were compared. The following conclusions were obtained: mozzarella type cheese and yogurt made from buffalo milk exhibited higher content of protein, fat, minerals, calcium and phosphorus when compared to those made from cow milk; in vitro digestibility tests of mozzarella type cheese and yogurt made from buffalo milk were similar to those of cow milk, indicantig suitable digestibility levels for human consumption.


O presente trabalho teve por objetivo verificar a composição química e nutricional do queijo e iogurte elaborados com leite de búfala e comparados com aqueles elaborados com leite de vaca. Dos resultados obtidos foram obtidas as seguintes conclusões: o queijo tipo mozzarella e o iogurte elaborado com leite de búfala apresentaram níveis superiores em proteína, gordura, cinzas, cálcio e fósforo, estando relacionados com a composição química inicial do leite. Os níveis de digestibilidade in vitro dos queijos tipo mozzarella e iogurte de leite de búfala apresentaram resultados semelhantes aos elaborados com leite de vaca, indicando níveis adequados de digestibilidade para consumo humano.

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