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1.
Bioresour Technol ; 402: 130804, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38718904

RESUMO

Lignin, a complex phenolic polymer crucial for plant structure, is mostly used as fuel but it can be harnessed for environmentally friendly applications. This article explores ozonation as a green method for lignin extraction from lignocellulosic biomass, aiming to uncover the benefits of the extracted lignin. A pilot-scale ozonation reactor was employed to extract lignin from Miscanthus giganteus (a grass variety) and vine shoots (a woody biomass). The study examined the lignin extraction and modification of the fractions and identified the generation of phenolic and organic acids. About 48 % of lignin was successfully extracted from both biomass types. Phenolic monomers were produced, vine shoots yielding fewer monomers than Miscanthus giganteus. Ozonation generated homogeneous lignin oligomers, although their molecular weight decreased during ozonation, with vine shoot oligomers exhibiting greater resistance to ozone. Extracted fractions were stable at 200 °C, despite the low molecular weight, outlining the potential of these phenolic fractions.


Assuntos
Lignina , Ozônio , Brotos de Planta , Poaceae , Lignina/química , Poaceae/química , Ozônio/química , Ozônio/farmacologia , Projetos Piloto , Brotos de Planta/química , Biomassa , Reatores Biológicos , Peso Molecular , Fenóis
2.
Carbohydr Polym ; 306: 120604, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36746590

RESUMO

In this work, nanostructured pectin aerogels were prepared via a sol-gel process and subsequent drying under supercritical conditions. To this end, three commercially available citrus pectins and an in-house produced and enzymatically modified watermelon rind pectin (WRP) were compared. Then, the effect of pectin's structure and composition on the aerogel properties were analysed and its potential application as a delivery system was explored by impregnating them with vanillin. Results showed that the molecular weight, degree of esterification and branching degree of the pectin samples played a main role in the production of hydrogels and subsequent aerogels. The developed aerogel particles showed high specific surface areas (468-584 m2/g) and low bulk density (0.025-0.10 g/cm3). The shrinkage effect during aerogel formation was significantly affected by the pectin concentration and structure, while vanillin loading in aerogels and its release profile was also seen to be influenced by the affinity between pectin and vanillin. Furthermore, the results highlight the interest of WRP as a carrier of active compounds which might have potential application in food and biomedical areas, among others.


Assuntos
Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Pectinas/química , Hidrogéis
3.
Acta ortop. mex ; 36(5): 292-296, sep.-oct. 2022. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1527649

RESUMO

Resumen: Introducción: a medida que se invierte la pirámide poblacional vamos a ver más pacientes que sufren fracturas por mecanismos de bajo impacto y no todos los hospitales cuentan con un densitómetro para hacer el diagnóstico definitivo. Sin embargo, se cuenta con herramientas clínicas que nos apoyan para iniciar con un tratamiento oportuno. Objetivo: reconocer el riesgo de refractura que existe en pacientes mayores de 50 años dentro de nuestra población. Material y métodos: se incluyeron a pacientes > 50 años que sufrieron de una fractura de bajo impacto en el Hospital Ángeles Mocel. Usando el FRAX score México para medir el riesgo de sufrir una fractura. Se dividió la muestra en dos grupos, utilizando una p < 0.05 para considerar estadísticamente significativa con un IC de 95%. Resultados: se incluyeron 69 pacientes, 47.8% ya habían sufrido de alguna fractura previa, 10% de ellos tienen tratamiento para la osteopenia. El riesgo de sufrir una fractura mayor osteoporótica en 10 años se observó en 50.7% de los pacientes. El riesgo de sufrir una fractura de cadera en 10 años se encontró en 75% de los pacientes. A ningún paciente se le dio tratamiento, ya sea modificadores del estilo de vida o tratamiento farmacológico para osteopenia/osteoporosis a su egreso hospitalario. Conclusión: hay una deficiencia en el manejo inmediato de los cirujanos ortopedistas para prevenir en pacientes futuras refracturas de bajo impacto.


Abstract: Introduction: as the population pyramid inverts, we'll see more old patients suffering a fracture secondary to a low impact mechanism and not all hospitals have a densitometer to make a definitive diagnosis. Nevertheless, we have clinical tools that can help us to start an early treatment. Objective: to recognize the risk of re-fracture of patients older than 50 years in our population. Material and methods: we included all patients older than 50 that suffered a low impact fracture in the Ángeles Mocel Hospital. We used Mexico FRAX score tool to determine de risk of suffering a fracture. The sample was divided in two groups. Utilizing p < 0.05 and a CI of 95%. Results: 69 patients where included. 47.8% had past fractures and only 10% of those had preventive osteoporotic treatment. 50.7% of the patients have a high risk of suffering a mayor osteoporotic fracture in 10 years and 75% of suffering a hip fracture in 10 years. None of the patients received a treatment, either lifestyle modifiers or specific osteoporosis pharmacotherapy at hospital discharge. Conclusion: there is a deficiency in the early preventive management of osteoporosis in patients suffering a low impact fracture by orthopedic surgeons.

4.
Acta Ortop Mex ; 36(5): 292-296, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-37402495

RESUMO

INTRODUCTION: as the population pyramid inverts, we'll see more old patients suffering a fracture secondary to a low impact mechanism and not all hospitals have a densitometer to make a definitive diagnosis. Nevertheless, we have clinical tools that can help us to start an early treatment. OBJECTIVE: to recognize the risk of re-fracture of patients older than 50 years in our population. MATERIAL AND METHODS: we included all patients older than 50 that suffered a low impact fracture in the Ángeles Mocel Hospital. We used Mexico FRAX score tool to determine de risk of suffering a fracture. The sample was divided in two groups. Utilizing p < 0.05 and a CI of 95%. RESULTS: 69 patients where included. 47.8% had past fractures and only 10% of those had preventive osteoporotic treatment. 50.7% of the patients have a high risk of suffering a mayor osteoporotic fracture in 10 years and 75% of suffering a hip fracture in 10 years. None of the patients received a treatment, either lifestyle modifiers or specific osteoporosis pharmacotherapy at hospital discharge. CONCLUSION: there is a deficiency in the early preventive management of osteoporosis in patients suffering a low impact fracture by orthopedic surgeons.


INTRODUCCIÓN: a medida que se invierte la pirámide poblacional vamos a ver más pacientes que sufren fracturas por mecanismos de bajo impacto y no todos los hospitales cuentan con un densitómetro para hacer el diagnóstico definitivo. Sin embargo, se cuenta con herramientas clínicas que nos apoyan para iniciar con un tratamiento oportuno. OBJETIVO: reconocer el riesgo de refractura que existe en pacientes mayores de 50 años dentro de nuestra población. MATERIAL Y MÉTODOS: se incluyeron a pacientes > 50 años que sufrieron de una fractura de bajo impacto en el Hospital Ángeles Mocel. Usando el FRAX score México para medir el riesgo de sufrir una fractura. Se dividió la muestra en dos grupos, utilizando una p < 0.05 para considerar estadísticamente significativa con un IC de 95%. RESULTADOS: se incluyeron 69 pacientes, 47.8% ya habían sufrido de alguna fractura previa, 10% de ellos tienen tratamiento para la osteopenia. El riesgo de sufrir una fractura mayor osteoporótica en 10 años se observó en 50.7% de los pacientes. El riesgo de sufrir una fractura de cadera en 10 años se encontró en 75% de los pacientes. A ningún paciente se le dio tratamiento, ya sea modificadores del estilo de vida o tratamiento farmacológico para osteopenia/osteoporosis a su egreso hospitalario. CONCLUSIÓN: hay una deficiencia en el manejo inmediato de los cirujanos ortopedistas para prevenir en pacientes futuras refracturas de bajo impacto.


Assuntos
Fraturas do Quadril , Osteoporose , Fraturas por Osteoporose , Humanos , Densidade Óssea , Fatores de Risco , Osteoporose/complicações , Osteoporose/epidemiologia , Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/prevenção & controle , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/etiologia , Fraturas do Quadril/prevenção & controle
5.
Genet Mol Res ; 15(3)2016 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-27525929

RESUMO

Weed resistance to herbicides is a natural phenomenon that exerts selection on individuals in a population. In Brazil, glyphosate resistance was recently detected in Digitaria insularis. The objective of this study was to elucidate mechanisms of weed resistance in this plant, including genetic variability, allelism, amino acid substitutions, gene expression, and enzymatic activity levels. Most of these have not previously been studied in this species. D. insularis DNA sequences were used to analyze genetic variability. cDNA from resistant and susceptible plants was used to identify mutations, alleles, and 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) expression, using real-time quantitative reverse transcription-polymerase chain reaction. In addition, EPSPS activity was measured. We found a decrease in genetic variability between populations related to glyphosate application. Substitutions from proline to threonine and tyrosine to cysteine led to a decrease in EPSPS affinity for the glyphosate. In addition, the EPSPS enzymatic activity was slightly higher in resistant plants, whereas EPSPS gene expression was almost identical in both biotypes, suggesting feedback regulation at different levels. To conclude, our results suggest new molecular mechanisms used by D. insularis to increase glyphosate resistance.


Assuntos
3-Fosfoshikimato 1-Carboxiviniltransferase/genética , Digitaria/enzimologia , Glicina/análogos & derivados , Herbicidas/farmacologia , Proteínas de Plantas/genética , 3-Fosfoshikimato 1-Carboxiviniltransferase/metabolismo , Substituição de Aminoácidos , Digitaria/efeitos dos fármacos , Digitaria/genética , Expressão Gênica , Glicina/farmacologia , Resistência a Herbicidas , Filogenia , Proteínas de Plantas/metabolismo , Polimorfismo Genético , Análise de Sequência de DNA , Glifosato
6.
Food Environ Virol ; 8(2): 125-32, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27008344

RESUMO

Cinnamaldehyde (CNMA), an organic compound that gives cinnamon its flavor and odor, was investigated for its virucidal activity on norovirus surrogates, murine norovirus (MNV) and feline calicivirus (FCV), and hepatitis A virus (HAV). Initially, different concentrations of CNMA (0.1, 0.5 and 1 %) were individually mixed with each virus at titers of ca. 6-7 log10 TCID50/ml and incubated 2 h at 4 and 37 °C. CNMA was effective in reducing the titers of norovirus surrogates in a dose-dependent manner after 2 h at 37 °C, while HAV titers were reduced by 1 log10 after treatment with 1 % of CNMA. When incubation time was extended, HAV titers were reduced by 3.4 and 2.7 log10 after overnight incubation at 37 °C with 1 and 0.5 % of CNMA, respectively. Moreover, this paper analyzed, for the first time, the antiviral activity of adding an active electrospun interlayer based on zein and CNMA to a polyhydroxybutyrate packaging material (PHB) in a multilayer form. Biodegradable multilayer systems prepared with 2.60 mg/cm(2) (~9.7 %) of CNMA completely inactivated FCV according to ISO 22196:2011, while MNV titers were reduced by 2.75 log10. When the developed multilayer films were evaluated after one month of preparation or at 25 °C, the antiviral activity was reduced as compared to freshly prepared multilayer films evaluated at 37 °C. The results show the excellent potential of this system for food contact applications as well as for active packaging technologies in order to maintain or extend food quality and safety.


Assuntos
Acroleína/análogos & derivados , Calicivirus Felino/efeitos dos fármacos , Embalagem de Alimentos/instrumentação , Vírus da Hepatite A/efeitos dos fármacos , Norovirus/efeitos dos fármacos , Acroleína/farmacologia , Animais , Calicivirus Felino/crescimento & desenvolvimento , Gatos , Desinfetantes/farmacologia , Contaminação de Alimentos/prevenção & controle , Vírus da Hepatite A/crescimento & desenvolvimento , Humanos , Camundongos , Norovirus/crescimento & desenvolvimento , Papel , Proibitinas , Inativação de Vírus/efeitos dos fármacos
7.
Int J Biol Macromol ; 47(4): 458-64, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20637226

RESUMO

Dietary components may have an important role in maintaining a balanced gut microbiota composition. Celiac disease is an autoimmune enteropathy caused by gliadins, and has been associated with a reduced proportion of Bifidobacterium in gut microbiota. This study evaluates the influence of glycosaminoglycans (GAGs) on bacterial adhesion and their contribution in the gliadins-induced inflammatory response. The adhesion of potential probiotic (Bifidobacterium longum CECT 7347 and Bifidobacterium bifidum CECT 7365), commensal (Escherichia coli and Bacteroides fragilis) and pathogenic (Salmonella enterica CECT 443 and Listeria monocytogenes CECT 935) bacteria to mucin and Caco-2 cell cultures was determined. Gliadins were subjected to in vitro digestion (pepsin/pancreatin-bile), with/out GAGs, and the presence or not of cell suspensions of B. longum (10(8) CFU/ml). B. longum, E. coli, and L. monocytogenes, markedly interact with the high-sulphur-containing fraction of GAGs. The GAGs reduced the gliadins-mediated production of interleukin-1ß, but not tumour necrosis factor-α. The results suggest that GAGs may ameliorate gliadin-induced inflammatory response, though they also slightly interfere with the action of B. longum.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Dieta , Enterócitos/efeitos dos fármacos , Enterócitos/patologia , Glicosaminoglicanos/farmacologia , Inflamação/patologia , Animais , Células CACO-2 , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Peixes , Gliadina , Humanos , Interleucina-1beta/biossíntese , Lectinas de Plantas/metabolismo , Proteínas de Soja/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Fator de Necrose Tumoral alfa/biossíntese
8.
Food Addit Contam ; 22(10): 988-93, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16227183

RESUMO

The objective was to demonstrate, as an example of an application, the potential of synchrotron X-ray analysis to detect morphological alterations that can occur in barrier packaging materials and structures. These changes can affect the packaging barrier characteristics when conventional food preservation treatments are applied to packaged food. The paper presents the results of a number of experiments where time-resolved combined wide-angle X-ray scattering and small-angle X-ray scattering analysis as a function of temperature and humidity were applied to ethylene-vinyl alcohol co-polymers (EVOH), polypropylene (PP)/EVOH/PP structures, aliphatic polyketone terpolymer (PK) and amorphous polyamide (aPA) materials. A comparison between conventional retorting and high-pressure processing treatments in terms of morphologic alterations are also presented for EVOH. The impact of retorting on the EVOH structure contrasts with the good behaviour of the PK during this treatment and with that of aPA. However, no significant structural changes were observed by wide-angle X-ray scattering in the EVOH structures after high-pressure processing treatment. These structural observations have also been correlated with oxygen permeability measurements that are of importance when guaranteeing the intended levels of safety and quality of packaged food.


Assuntos
Contaminação de Alimentos , Embalagem de Alimentos/normas , Plásticos , Síncrotrons , Exposição Ambiental/efeitos adversos , Conservação de Alimentos/métodos , Humanos , Umidade , Nylons , Oxigênio/química , Permeabilidade , Polipropilenos , Polivinil , Pressão , Segurança , Espalhamento de Radiação , Temperatura
9.
Rev Neurol ; 35(3): 201-5, 2002.
Artigo em Espanhol | MEDLINE | ID: mdl-12235578

RESUMO

OBJECTIVE: This study gives information about a parent training program and a clinical trial with a stimulant drug (methylphenidate) to reduce the symptoms of attention deficit hiperactivity disorder (ADHD) in a group of children in Venezuela. PATIENTS AND METHODS: 24 children, aged between 6 and 10 years and diagnosed as having ADHD, identified in ADHD screening days, were randomly assigned to two groups of treatment: parent training and a stimulant drug (methylphenidate). RESULTS: Both groups showed an improvement in their symptoms, to different degrees, after treatment. The differences were statistically significant, as evaluated by their parents, regarding the symptoms of inattention, hyperactivity and impulsivity. The teachers observed a significant improvement for the medication group with respect to the symptoms of hyperactivity and impulsivity, but no change in the inattention, whilst in the parent training group there was only significant difference in the ADHD index. There was no difference in the effectiveness of the two types of treatment. CONCLUSIONS: When the two programs of treatment were compared it was observed that both parent training and psychostimulant medication were effective in reducing the symptoms of ADHD. Although there was no difference in the effectiveness of the two programs, there was a tendency for medication to be more effective


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Metilfenidato/uso terapêutico , Pais/educação , Criança , Feminino , Humanos , Masculino , Projetos Piloto
10.
Ann Allergy Asthma Immunol ; 85(3): 215-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11030276

RESUMO

BACKGROUND: Although the vast majority of IgE-mediated allergic reactions to foods occurs through ingestion, a few cases of unexpected allergic reactions to foods may occur through the exposure to airborne food allergen particles. METHODS: Case reports. Skin prick tests and serum-specific IgE (CAP-FEIA) were used to identify specific IgE antibodies. Bronchial provocation tests were performed to determine the clinical relevance of inhaled exposure to raw and cooked green beans and raw chards. After demonstrating specific reactivity to them, SDS-PAGE and immunoblotting of raw and cooked green beans were carried out to identify relevant antigens. RESULTS: Three women developed bronchial asthma and rhinitis after exposure to raw green beans, and one of them also when exposed to raw chards. All women tolerated ingestion of green beans. Patients reported multiple episodes while handling these vegetables for cooking activities. Allergy to green beans and chards was demonstrated by skin testing and serum-specific IgE. Bronchial challenge test with these allergens showed positive responses to raw, but not cooked, green beans and chards. Oral food challenges with green beans (raw and cooked) and chards were negative in all patients. In order to further characterize the allergenic components of these extracts, SDS-PAGE and electroblotting studies were also performed. Immunoblots of raw and cooked green beans extract showed two IgE-binding bands with apparent molecular weights of 41.1 and 70.6 kD. Interestingly, a 47-kD IgE-binding protein was detected only in raw green bean extracts. CONCLUSIONS: We report three patients who developed asthma and rhinitis caused by exposure to raw, but not to cooked, green beans and chards in a non-occupational environment. Only minor differences of IgE reactivity between nitrocellulose-blotted raw and boiled green bean extract were found.


Assuntos
Asma/imunologia , Fabaceae/efeitos adversos , Hipersensibilidade Alimentar/complicações , Plantas Medicinais , Rinite/imunologia , Verduras/efeitos adversos , Adulto , Feminino , Hipersensibilidade Alimentar/etiologia , Humanos , Hipersensibilidade Imediata/diagnóstico , Hipersensibilidade Imediata/imunologia , Imunoglobulina E/imunologia , Testes Cutâneos
11.
J Allergy Clin Immunol ; 106(1 Pt 1): 183-9, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10887323

RESUMO

BACKGROUND: Foods from the Rosaceae botanical family have been increasingly reported as causes of allergic reaction. Patients frequently have positive skin tests or radioallergosorbent test results for multiple members of this botanical family. OBJECTIVE: Our purpose was to investigate the clinical cross-reactivity assessed by double-blind, placebo-controlled food challenge (DBPCFC) of Rosaceae foods (apricot, almond, plum, strawberry, apple, peach, and pear). METHODS: Thirty-four consecutive adult patients complaining of adverse reactions to Rosaceae were included in the study. Skin prick tests and CAP System (FEIA) were performed with Rosaceae foods in all patients. Clinical reactivity to Rosaceae was systematically evaluated by open food challenges (OFCs), unless there was a convincing history of a recent severe anaphylaxis. Positive reactions on OFCs were subsequently evaluated by DBPCFCs. RESULTS: Twenty-six and 24 patients had positive skin prick tests and CAP FEIA with Rosaceae, respectively; from these 88% and 100% had positive tests with >/=2. No evidence of clinical reactivity was found in 66% percent of positive skin prick tests and 63% of positive specific IgE determinations to fruits. A total of 226 food challenges (including OFC and DBPCFC) were performed in the 28 patients with positive skin prick tests or CAP System FEIA. Of 182 initial OFCs carried out, 26 (14%) reactions were confirmed by DBPCFCs. Overall, 40 reactions were considered positive in 22 patients with positive skin tests or CAP FEIA. Thirty-eight reactions had been previously reported, the remaining two were detected by systematic challenges. Most reactions were caused by peach (22 patients), apple (6), and apricot (5). Ten patients (46%) were clinically allergic to peach and other Rosaceae. CONCLUSION: Positive skin test and CAP System FEIA should not be taken as the only guide for multi-species dietary restrictions. Nevertheless, the potential clinical allergy to other Rosaceae should not be neglected. If the reported reaction is confirmed, current tolerance to other Rosaceae should be precisely established unless there has been ingestion without symptoms after the reaction.


Assuntos
Hipersensibilidade Alimentar/imunologia , Frutas/efeitos adversos , Rosales/imunologia , Adolescente , Adulto , Reações Cruzadas , Eletroforese em Gel Bidimensional , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Cutâneos
13.
Allergy ; 53(12): 1216-20, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9930601

RESUMO

BACKGROUND: Vegetables of the Liliaceae family, such as garlic or onion, have been reported to cause occupational asthma. However, there are few data on adverse reactions to asparagus. We evaluated the role of asparagus as a cause of asthma in a patient with respiratory symptoms occurring at work (horticulture) and studied relevant allergens. METHODS: A 28-year-old man complained of rhinoconjunctivitis and asthma when harvesting asparagus at work. Eating cooked asparagus did not provoke symptoms. A positive skin test reaction was observed with raw asparagus, Alternaria alternata, and grass-pollen extracts. The methacholine test demonstrated mild bronchial hyperresponsiveness. The patient had an immediate asthmatic response after challenge with raw asparagus extract. Bronchial provocation tests with boiled asparagus, A. alternata, and control extracts were negative. Two unexposed subjects with seasonal allergic asthma did not react to the raw asparagus extract. RESULTS: The double-blind, placebo-controlled food challenge with raw asparagus was negative. Serum asparagus-specific IgE was 13.9 kU(A)/l. By SDS-PAGE immunoblot, at least six IgE-binding components, ranging from 22 to 73 kDa, were detected only in raw asparagus. CONCLUSIONS: We report a case of occupational asthma caused by asparagus inhalation, confirmed by specific bronchoprovocation. Immunoblot analysis showed that asparagus allergens are very labile and quite sensitive to heat denaturation.


Assuntos
Asma/imunologia , Liliaceae/imunologia , Doenças Profissionais/imunologia , Adulto , Alérgenos/análise , Alérgenos/imunologia , Antígenos de Diferenciação/análise , Culinária , Método Duplo-Cego , Eletroforese em Gel Bidimensional , Galectina 3 , Humanos , Immunoblotting , Imunoglobulina E/sangue , Liliaceae/química , Masculino , Placebos
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