RESUMO
Four aromatic acid compounds: benzoic acid (Bz), 4-hydroxyphenylpropionic acid (HPPA), gallic acid (GA) and 4-aminobenzoic acid (PABA) were covalently bonded to chitosan in order to improve water solubility at neutral pH. The synthesis was performed via a radical redox reaction in heterogeneous phase by employing ascorbic acid and hydrogen peroxide (AA/H2O2) as radical initiators in ethanol. The analysis of chemical structure and conformational changes on acetylated chitosan was also the focus of this research. Grafted samples exhibited as high as 0.46 M degree of substitution (MS) and excellent solubility in water at neutral pH. Results showed a correlation between the disruption of C3-C5 (O3 O5) hydrogen bonds with increasing solubility in grafted samples. Spectroscopic techniques such as FT-IR and 1H and 13C NMR showed modifications in both glucosamine and N-Acetyl-glucosamine units by ester and amide linkage at C2, C3 and C6 position, respectively. Finally, loss of crystalline structure of 2-helical conformation of chitosan after grafting was observed by XRD and correlated with 13C CP-MAS-NMR analyses.
RESUMO
INTRODUCCIÓN A pesar del incremento de infecciones por VIH en mujeres, la intervención médica y política se ha centrado en el cumplimiento de los aspectos técnicos para evitar la transmisión perinatal del virus. OBJETIVOS Recuperar saberes y prácticas, demandas y estrategias desarrolladas por las mujeres a partir de la experiencia de vivir y atenderse con VIH, sobre la base de un análisis de los procesos de reconstrucción biográfica. MÉTODOS Se desarrolló una investigación cualitativa basada en el estudio de narrativas. Se realizaron 12 entrevistas en profundidad a mujeres infectadas con VIH que fueron madres con posterioridad al diagnóstico o que fueron diagnosticadas durante el embarazo, parto o puerperio. RESULTADOS La investigación reveló que el proceso de reconocerse a sí misma como afectada por el VIH no representaba un momento puntual, sino más bien un proceso relacional de variable duración, a partir del cual las personas podían (o no) armar un relato y desarrollar recursos para reorganizar y normalizar la vida, afrontar la incertidumbre y la estigmatización, aprender sobre la enfermedad y el tratamiento y enfrentar, conocer y relacionarse con los servicios de salud y otras instituciones. DISCUSIÓN El estudio plantea la necesidad de construir una mirada crítica sobre la concepción intelectualista del sujeto. Esto supone reconocer la complejidad de experiencias y la variabilidad de procesos movilizados al vivir y atenderse con VIH-sida.
Assuntos
Mulheres , HIVRESUMO
Mixtures of a nonionic surfactant and non-functionalized nanohydroxyapatite (NHA) enhanced the stability of oil-in-eutectic mixture high internal phase emulsions (HIPEs). Upon ring opening polymerization of the eutectic mixture composed of l-lactide and ε-caprolactone, biodegradable polyHIPEs with specific cavity sizes and selective interfacial functionalization with NHA are produced.
RESUMO
OBJECTIVE: To assess the tolerance of a sterile isotonic electrolyte solution containing select recombinant growth factors enterally administered in neonates who were NPO because of necrotizing enterocolitis (NEC). STUDY DESIGN: A phase I trial was accomplished among 30 neonates. Patients received 5, 10, or 20 mL enterally of the study solution/kg/day divided into every 3-hour dosing, for 3 days prior to when feedings of milk were to resume. The occurrence of emesis, gastric residuals, diarrhea, bloody stools, abdominal distention, skin rashes and death were sought. RESULTS: Gestational ages ranged from 25.2 to 41.1 weeks. A total of 16 neonates had Stage IA NEC, six Stage IB, and eight Stage IIA. The solution was well tolerated in all 30; none developed diarrhea, guaiac positive or bloody stools, or abdominal distention. Administration of the solution was not prematurely discontinued in any infant. Two neonates died secondary to late-onset sepsis remote from the study period. CONCLUSIONS: Enteral administration of a sterile isotonic electrolyte solution containing select recombinant growth factors was well tolerated by neonates with NEC.
Assuntos
Enterocolite Necrosante/terapia , Eritropoetina/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Intestinos/efeitos dos fármacos , Cloreto de Sódio/administração & dosagem , Enterocolite Necrosante/fisiopatologia , Epoetina alfa , Filgrastim , Humanos , Alimentos Infantis , Recém-Nascido , Soluções Isotônicas , Proteínas RecombinantesRESUMO
Describe el comportamiento del método RAOS (Remoción de Arsénico por Oxidación Solar) para la remoción del arsénico de aguas de consumo humano en regiones rurales de la prov. de Tucumán
Assuntos
Arsênio , Zona Rural , Remoção de Contaminantes , ArgentinaRESUMO
OBJECTIVES: Using the approach of a meta-analysis, we sought to determine whether the administration of recombinant erythropoietin (rEpo) to very low birth weight (VLBW) infants, after the first week of life, results in fewer "late" transfusions. STUDY DESIGN AND METHODS: The guidelines set forth by the Cochrane Neonatal Review Group were used to identify all relevant studies. Medline was searched from January 1990 to November of 2000. Studies that used a randomized, placebo-controlled, and double-masked design were deemed acceptable. RESULTS: Eight studies meet the inclusion criteria. These involved 357 VLBW neonates: 183 rEpo and 174 placebo recipients. The neonates in the rEpo group received fewer erythrocyte transfusions during the study period than did those in the placebo group; the common odds ratio (OR)=0.33; 95% confidence interval (CI) 0.21-0.51. Furthermore, the rEpo effect size was a function of the dose of rEpo administered (p=0.0001). CONCLUSION: A meta-analysis of the most scientifically rigorous studies on this topic indicates that administration of rEpo to VLBW infants reduces "late" erythrocyte transfusions in a dose-dependent manner.
Assuntos
Transfusão de Sangue/estatística & dados numéricos , Eritropoetina/administração & dosagem , Doenças do Recém-Nascido/tratamento farmacológico , Recém-Nascido de muito Baixo Peso , Transfusão de Sangue/métodos , Intervalos de Confiança , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Recém-Nascido , Doenças do Recém-Nascido/diagnóstico , Doenças do Recém-Nascido/terapia , Unidades de Terapia Intensiva Neonatal , Masculino , Razão de Chances , Probabilidade , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Proteínas Recombinantes , Sensibilidade e Especificidade , Resultado do TratamentoRESUMO
The effects of water stress on leaf water relations and growth are reported for three perennial tussock grass genotypes under glasshouse conditions. Studies were performed in genotypes El Palmar INTA and Selección Anguil of Agropyron scabrifolium (Döell) Parodi, and El Vizcachero of A. elongatum (Host) Beauv. Agropyron scabrifolium El Palmar INTA is native to a region with warm-temperate and humid climate without a dry season, and an average annual precipitation of 900 mm. Agropyron scabrifolium Selección Anguil comes from a region with a sub-humid, dry to semiarid climate and a mean annual precipitation of 600 mm. Agropyron elongatum is a widespread forage in semiarid Argentina with well-known water stress resistance. A mild water stress treatment was imposed slowly; plants reached a minimum pre-dawn leaf water potential of about -1.83 MPa by day 21 after watering was withheld. In all genotypes, water stress led to a reduction of leaf growth. There was a tendency for a greater epicuticular wax accumulation on water-stressed plants of A. scabrifolium Selección Anguil and A. elongatum than on those of A. scabrifolium El Palmar INTA. This may have contributed to obtain greater turgor pressures and relative water contents in the first two than in the later genotype. In turn, this may have contributed to determine smaller leaf growth rate reductions in A. scabrifolium Selección Anguil and A. elongatum than in A. scabrifolium El Palmar INTA under water stress. This study demonstrated variation in water stress resistance between genotypes in A. scabrifolium, and between A. scabrifolium Selección Anguil and A. elongatum versus A. scabrifolium El Palmar INTA, which was related to their differential responses in water relations.
Assuntos
Agropyron/genética , Agropyron/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Água/metabolismo , Agricultura , Agropyron/efeitos dos fármacos , Desastres , Pressão Osmótica , Folhas de Planta/efeitos dos fármacos , Fatores de Tempo , Água/farmacologia , Ceras/análiseRESUMO
The effects of water stress on leaf water relations and growth are reported for three perennial tussock grass genotypes under glasshouse conditions. Studies were performed in genotypes El Palmar INTA and Selección Anguil of Agropyron scabrifolium (D÷ell) Parodi, and El Vizcachero of A. elongatum (Host) Beauv. Agropyron scabrifolium El Palmar INTA is native to a region with warm-temperate and humid climate without a dry season, and an average annual precipitation of 900 mm. Agropyron scabrifolium Selección Anguil comes from a region with a sub-humid, dry to semiarid climate and a mean annual precipitation of 600 mm. Agropyron elongatum is a widespread forage in semiarid Argentina with well-known water stress resistance. A mild water stress treatment was imposed slowly; plants reached a minimum pre-dawn leaf water potential of about -1.83 MPa by day 21 after watering was withheld. In all genotypes, water stress led to a reduction of leaf growth. There was a tendency for a greater epicuticular wax accumulation on water-stressed plants of A. scabrifolium Selección Anguil and A. elongatum than on those of A. scabrifolium El Palmar INTA. This may have contributed to obtain greater turgor pressures and relative water contents in the first two than in the later genotype. In turn, this may have contributed to determine smaller leaf growth rate reductions in A. scabrifolium Selección Anguil and A. elongatum than in A. scabrifolium El Palmar INTA under water stress. This study demonstrated variation in water stress resistance between genotypes in A. scabrifolium, and between A. scabrifolium Selección Anguil and A. elongatum versus A. scabrifolium El Palmar INTA, which was related to their differential responses in water relations.