Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros












Intervalo de ano de publicação
1.
Nanotechnology ; 30(2): 025601, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-30387444

RESUMO

Polyacrylonitrile nonwovens intercalated with graphene oxide (GO) sheets were prepared by a simultaneous electrospinning-spray deposition system. These hybrid nonwovens were carbonized in a two-stage process to obtain a mesostructured hybrid carbon containing carbon nanofibers (CNF) and reduced GO sheets (CNF/RGO). During the carbonization process, the CNF act as spacers between the RGO layers to prevent their compactation and restacking resulting in a three-dimensional structure. The presence of RGO increases the electrical conductivity in the CNF/RGO material. The resulting hybrid carbon is nitrogen-doped as indicated by x-ray photoelectron spectroscopy and Fourier transformed infrared spectroscopy. This N-doped porous carbon was used to prepare electrodes with improved sensitivity for the electrochemical detection of L-cysteine.

2.
J Bone Joint Surg Br ; 85(8): 1166-8, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14653601

RESUMO

Of 22 infants aged between 11 and 29 months who underwent a combined reconstruction of the upper brachial plexus and shoulder for the sequelae of a birth injury, 19 were followed up for two or more years. The results were evaluated using a modified Gilbert scale. Three patients required a secondary procedure before follow-up. Three patients had a persistent minor internal rotation contracture. All improved by at least two grades on a modified Gilbert scale.


Assuntos
Plexo Braquial/lesões , Paralisia Obstétrica/cirurgia , Articulação do Ombro/cirurgia , Plexo Braquial/cirurgia , Pré-Escolar , Doença Crônica , Contratura/cirurgia , Seguimentos , Humanos , Lactente , Recém-Nascido , Transferência de Nervo/métodos , Procedimentos Ortopédicos/métodos , Índice de Gravidade de Doença , Luxação do Ombro/cirurgia , Fatores de Tempo , Resultado do Tratamento
3.
J Econ Entomol ; 95(4): 856-61, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12216831

RESUMO

Beat sampling and two type of traps, cup traps and Tedders traps, were evaluated as sampling methods to detect and estimate population densities of adult Diaprepes abbreviatus L. weevils newly colonizing young citrus trees. The study was conducted over a 65-wk period across a 0.25-ha area of 80 citrus trees [Citrus sinensis (L.) Osbeck] (1.2-1.5 m tall). Beat samples were taken weekly to determine the number of trees infested and number of new adult weevils per tree. Sixteen of the 80 trees studied were each monitored weekly using one of the following trapping methods: cup traps in trees, cup traps on a stake in the ground within the tree drip line, cup traps on a stake in the ground outside of the drip line, Tedders traps on the ground within the drip line, and Tedders traps on the ground outside of the drip line. Weevils collected each week from trees and traps were removed from the study site. Based on the coefficients associated with Taylor's power law, the optimum numbers of trees to sample for an SEM equal to 25% of the mean estimate decreased from 50 trees at a mean of 0.5 new weevils per tree to 30 trees at a mean of 0.8 new weevils per tree. A significant relationship was found between the weekly mean number of new weevils per tree and the proportion of trees infested, a binomial relationship that could be further explored in the search for a sampling program for adult D. abbreviatus. Regression analyses indicated that three of the trapping methods served at least as weak indices of the presence and abundance of new weevils: cup traps in trees, Tedders traps inside the dripline and Tedders traps outside the dripline. Cup traps in trees and Tedders traps inside the dripline captured the most weevils and most frequently detected weevils. Although relatively inefficient as abundance indices of populations of new weevils, these two trapping methods appeared to have some value with respect to signaling when weevils first appeared in trees during the spring.


Assuntos
Citrus , Besouros , Controle de Insetos , Animais , Interpretação Estatística de Dados , Controle de Insetos/métodos , Densidade Demográfica
4.
J Econ Entomol ; 93(5): 1485-92, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11057722

RESUMO

When flies were treated with 0- 0.5% sodium tetraborate by feeding for 24 h, mortality in treatments was not different from controls. Fecundity and fertility were reduced by 0.5% sodium tetraborate. When flies were fed for 48 h, mortality of both males and females increased in the 0.5% sodium tetraborate treatment; oviposition was eliminated for 20 d after treatment. When treatment was extended to 168 h, 0.1% sodium tetraborate caused increased mortality and decreased fecundity and fertility. Fed for 168 h, 0.2 and 0.5% sodium tetraborate killed almost all flies within the 7-d treatment. Oviposition of survivors in 0.1 and 0.2% sodium tetraborate treatments was arrested for 20 d after treatment.


Assuntos
Boratos , Dípteros , Inseticidas , Animais , Dípteros/fisiologia , Feminino , Fertilidade , Controle de Insetos/métodos , Masculino
5.
Semin Pediatr Neurol ; 7(1): 52-7, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10749514

RESUMO

An aggressive and integrated physical and occupational therapy program is essential in the treatment of congenital brachial plexus injuries and other severe upper extremity nerve injuries. This article addresses the evaluation, identification of needs, establishment of goals, and the approaches to rehabilitation treatment for patients with brachial plexus palsy and other peripheral nerve injuries. Rehabilitative therapy can preserve and build on gains made possible by medical or surgical interventions; however, therapy is vital to these children regardless of whether surgery is indicated. The therapist uses a problem-solving approach to evaluate the patient and select appropriate occupational and physical therapy treatment modalities. Therapy is continually adjusted based on each child's unique needs. An understanding of the therapy principles aids in making appropriate referrals and prescriptions, and helps to coordinate care between the therapist, pediatrician, neurologist, and surgeon.


Assuntos
Neuropatias do Plexo Braquial/reabilitação , Paralisia Obstétrica/reabilitação , Amplitude de Movimento Articular , Articulação do Ombro/fisiopatologia , Criança , Humanos , Terapia Ocupacional/métodos , Modalidades de Fisioterapia/métodos , Recuperação de Função Fisiológica
6.
Rapid Commun Mass Spectrom ; 14(6): 408-16, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10717649

RESUMO

The gas-phase reactions of dimethyl ether (DME) ions with a number of biologically active arylalkylamines of the general formula R(1)R(2)C(6)H(3)CHR(3)(CH(2))(n)NR(4)R(5), where R(1) = H or OH, R(2) = H, F, NO(2), OH or OCH(3), R(3) = H or OH, R(4) and R(5) = H or CH(3), have been studied by means of chemical ionization mass spectrometry. Under the experimental conditions used, the most abundant DME ion is the methoxymethyl cation (CH(3)OCH(2)(+), m/z 45). The unimolecular metastable decompositions of the [M + 45](+), [M + 13](+) and [M + 15](+) adducts formed have been interpreted in terms of the initial site of reaction with the amines and the presence of different functional groups in the molecule. This has permitted establishment of general fragmentation patterns for the adducts, and their correlation with structural features of the molecules. The main site of reaction of the ion CH(3)OCH(2)(+) with the amines seems to be the amino group, particularly if the amine is primary, although a competition with attack on the aromatic ring and especially on the benzylic hydroxy group is observed. In a few cases the reaction mechanisms have been elucidated through the use of deuterated amines obtained by H/D exchange with D(2)O.


Assuntos
Alcanos/síntese química , Éteres Metílicos/química , Aminas Biogênicas/química , Espectrometria de Massas
7.
J Hand Surg Br ; 24(1): 43-5, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10190603

RESUMO

Seven children were operated on for pronation contractures of the forearm due to obstetric brachial plexus injuries. All underwent extensive preoperative evaluations to determine the extent of injury, secondary deformities, and capacity to perform a few basic tasks. Sequential video studies were used to document these findings. Operative procedures performed included various combinations of tendon/muscle lengthenings and/or transfers. Postoperative evaluations focused on function rather than gains in active range of motion and the patient/parental assessment of the benefit of the procedure by response to a questionnaire. All patients were followed for a minimum of I year following surgery. The average gain in active supination was 45 degrees. Each patient showed significant functional gains with a high degree of satisfaction.


Assuntos
Traumatismos do Nascimento/cirurgia , Plexo Braquial/lesões , Contratura/cirurgia , Antebraço/cirurgia , Adolescente , Criança , Pré-Escolar , Contratura/etiologia , Feminino , Seguimentos , Antebraço/fisiopatologia , Humanos , Masculino , Pronação , Inquéritos e Questionários , Transferência Tendinosa , Resultado do Tratamento
8.
Neurosci Lett ; 262(1): 33-6, 1999 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-10076866

RESUMO

The protooncogene Bcl-2 inhibits apoptosis in neural cells, which may involve mitochondrial stabilization and decreased generation of reactive oxygen species. Using in vivo microdialysis we found that following administration of the mitochondrial toxin 3-nitropropionic acid (3-NP) there was a significant increase in the conversion of 4-hydroxybenzoic acid (4-HBA) to 3,4-dihydroxybenzoic acid (3,4-DHBA) in control mice, but not in Bcl-2 overexpressing mice. Striatal lesions were observed in littermate control mice, whereas, lesions were minimal or absent in Bcl-2 overexpressing mice. This shows that Bcl-2 overexpression in vivo attenuates the generation of reactive oxygen species.


Assuntos
Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Animais , Anti-Hipertensivos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Feminino , Camundongos , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias/fisiologia , Neurotoxinas/farmacologia , Nitrocompostos , Estresse Oxidativo/efeitos dos fármacos , Propionatos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Succinato Desidrogenase/antagonistas & inibidores
9.
Rev Neurol ; 27(156): 271-3, 1998 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-9736958

RESUMO

OBJECTIVE AND METHODS: A variety of surgical procedures exist for early repair of the nerve injury in obstetrical brachial plexus palsy, including neuroma excision and nerve grafting, neurolysis and neurotization. Secondary deformities of the shoulder, forearm, and hand can similarly be reconstructed using soft tissue and skeletal procedures. This review describes our surgical approach to maximize the ultimate functional outcome in infants and children with obstetrical brachial plexus palsy.


Assuntos
Plexo Braquial/cirurgia , Paralisia Obstétrica/cirurgia , Contratura/fisiopatologia , Contratura/terapia , Antebraço/cirurgia , Mãos/cirurgia , Humanos , Lactente , Músculo Esquelético/fisiopatologia , Terapia Ocupacional/métodos , Modalidades de Fisioterapia/métodos , Amplitude de Movimento Articular , Ombro/anormalidades , Ombro/cirurgia
10.
J Neurochem ; 71(3): 1321-4, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9721759

RESUMO

Mutations in the enzyme copper/zinc superoxide dismutase-1 (SOD1) are associated with familial amyotrophic lateral sclerosis (FALS). The means by which the mutations cause FALS appears to be due to an adverse property of the mutant SOD1 protein that may involve increased generation of free radicals. We used in vivo microdialysis to measure the conversion of 4-hydroxybenzoic acid to 3,4-dihydroxybenzoic acid (3,4-DHBA) as a measure of "hydroxyl radical-like" production in transgenic amyotrophic lateral sclerosis (ALS) mice with the G93A mutation as well as littermate controls. The conversion of 4-hydroxybenzoic acid to 3,4-DHBA was significantly increased in the striatum of transgenic ALS mice at baseline but not in mice overexpressing wild-type human SOD1. Following administration of 3-nitropropionic acid 3,4-DHBA generation was significantly increased as compared with baseline, and the increase in the transgenic ALS mice was significantly greater than those in controls, whereas the increase in mice overexpressing wild-type human SOD1 was significantly attenuated. The present results provide in vivo evidence that expression of mutations in SOD1 can lead to increased generation of "hydroxyl radical-like" activity, which further implicates oxidative damage in the pathogenesis of ALS.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Radical Hidroxila/metabolismo , Esclerose Lateral Amiotrófica/genética , Animais , Corpo Estriado/metabolismo , Humanos , Hidroxibenzoatos/metabolismo , Camundongos , Camundongos Transgênicos/genética , Microdiálise , Neurotoxinas/farmacologia , Nitrocompostos , Parabenos/metabolismo , Propionatos/farmacologia , Superóxido Dismutase/genética , Superóxido Dismutase-1
11.
Ann Chir Main Memb Super ; 16(4): 305-9, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9479439

RESUMO

We developed a protocol to improve the final total active motion for patients with isolated unicondylar fractures of the head of the proximal phalanx. The protocol includes surgical treatment followed by hand therapy. Surgical fixation is obtained using lag screw technique. Therapy includes immediate mobilization by use of a continuous passive motion machine and controlled active motion. Specially designed splints and Coban wrap are used to control the position of the digit during the first six months following surgery. Silastic gel is used to control scarring. We treated five consecutive patients over a 4-year period using this protocol. Final total active motion of the injured digit averaged 241 degrees--approximately 90% of the normal range of 260 to 270 degrees. No patients required secondary surgery.


Assuntos
Parafusos Ósseos , Traumatismos dos Dedos/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Terapia Passiva Contínua de Movimento , Contenções , Adolescente , Adulto , Traumatismos dos Dedos/diagnóstico por imagem , Traumatismos dos Dedos/fisiopatologia , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/fisiopatologia , Humanos , Masculino , Radiografia , Amplitude de Movimento Articular
12.
Fundam Appl Toxicol ; 33(2): 272-81, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8921346

RESUMO

The purpose of these experiments was to determine the reversibility of alpha-chaconine and alpha-solanine inhibition of human plasma butyrylcholinesterase (BuChE). For the substrate alpha-naphthylacetate, optimal assay conditions were 0.50 M sodium phosphate buffer and a substrate concentration of 3-5 x 10(-4) M. Dibucaine (1 x 10(-5) M) indicated the usual phenotype for all subjects; alpha-chaconine and alpha-solanine at 2.88 x 10(-6) M inhibited BuChE about 70 and 50%, respectively. One- and 24-hr incubations at 1 x 10(-5) M with alpha-chaconine, alpha-solanine, paraoxon, eserine, and ethanol yielded reversible inhibition with dilution except for paraoxon. Twenty-four-hour dialyses of incubations showed no inhibition except for paraoxon. PAGE enzyme activity gels of 1- and 24-hr incubations also showed no inhibition except for paraoxon. alpha-Chaconine and alpha-solanine are reversible inhibitors of human butyrylcholinesterase. At estimated tissue levels, alpha-chaconine, alpha-solanine, and solanidine inhibited BuChE 10-86%. In assays which combined alpha-chaconine, alpha-solanine, and solanidine, inhibition of BuChE was less than additive. No inhibition of albumin alpha-naphthylacetate esterase (an arylesterase) was noted with any inhibitor. The importance of these data to adverse toxicological effects of potato alkaloids is discussed.


Assuntos
Butirilcolinesterase/sangue , Inibidores da Colinesterase/farmacologia , Solanina/análogos & derivados , Solanina/farmacologia , Eletroforese em Gel de Poliacrilamida , Humanos , Paraoxon/farmacologia , Especificidade por Substrato
14.
Guatemala; INCAP; Oct. 1993. 8 p. (INCAP/CI/005).
Monografia em Inglês | LILACS | ID: lil-311834

RESUMO

Qualitative information was collected of 64 indigenous women in highland Guatemalan and 73 mestizo women throughout El Salvador via in-depth interviews and direct observations prior to the design of education/communication programs. Data were collected on beliefs, attitudes and values related to infant feeding in the first 24-36 months and on actual breastfeeding and weaning practices during health and illness. Findings on cultural factors were related to the infant feeding decisions of interviewed women and to patterns of breastfeeding initiation, exclusive breastfeeding, introduction of liquids and weaning foods into infants' diets. In both settings, despite important differences in cultural traditions, women hold very similar and strong beliefs, attitudes and values towards the qualities of breastmilk, breastfeeding, the nutritional needs of young children, and their own capacity of produce adequate quantities of milk of acceptable quality. These cultural factors color their interpretation of infant behaviors such as crying and influence their day-to-day decisions about infant feeding. Dominant in the resulting suboptimal feeding patterns is the almost complete absence of exclusive breastfeeding beyond the second month. These findings demostrate the persistence of cultural factors in infant feeding practices in the early months


Assuntos
Humanos , Recém-Nascido , Lactente , Pré-Escolar , Aleitamento Materno , Conhecimentos, Atitudes e Prática em Saúde , Nutrição do Lactente , América Central , El Salvador , Guatemala
15.
s.l; s.e; s.f. 8 p. (INCAP/CI/005).
Monografia em Inglês | LILACS | ID: lil-169370

RESUMO

Qualitative information was collected of 64 indigenous women in highland Guatemalan and 73 mestizo women throughout El Salvador via in-depth interviews and direct observations prior to the design of education/communication programs. Data were collected on beliefs, attitudes and values related to infant feeding in the first 24-36 months and on actual breastfeeding and weaning practices during health and illness. Findings on cultural factors were related to the infant feeding decisions of interviewed women and to patterns of breastfeeding initiation, exclusive breastfeeding, introduction of liquids and weaning foods into infants' diets. In both settings, despite important differences in cultural traditions, women hold very similar and strong beliefs, attitudes and values towards the qualities of breastmilk, breastfeeding, the nutritional needs of young children, and their own capacity of produce adequate quantities of milk of acceptable quality. These cultural factors color their interpretation of infant behaviors such as crying and influence their day-to-day decisions about infant feeding. Dominant in the resulting suboptimal feeding patterns is the almost complete absence of exclusive breastfeeding beyond the second month. These findings demostrate the persistence of cultural factors in infant feeding practices in the early months


Assuntos
Humanos , Feminino , Lactente , Aleitamento Materno , América Central , El Salvador , Guatemala , Conhecimentos, Atitudes e Prática em Saúde , Nutrição do Lactente
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...