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1.
Rev. Inst. Adolfo Lutz (Online) ; 77: e1749, 2018. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1489579

RESUMO

As doenças fúngicas invasivas têm sido um problema crescente em ambientes hospitalares, sobretudo nas últimas duas décadas. A aspergilose invasiva (AI), ocasionada pelo gênero Aspergillus, está entre as principais causas de morte em pacientes gravemente imunocomprometidos, com mortalidade que varia de 70 a 90%. O padrão de referência para o diagnóstico de AI é o cultivo do micro-organismo e a análise histopatológica dos órgãos afetados. Estes procedimentos são dificilmente realizados na maioria dos casos, e apresentam baixa sensibilidade (<50%), além de as amostras serem habitualmente obtidas em estados avançados da infecção. O teste de detecção de galactomanana tem sido objeto de estudo para o diagnóstico de AI, por representar uma promissora ferramenta e por ser uma técnica sorológica rápida e não invasiva. A presente revisão tem por objetivo fazer levantamento de estudos que utilizaram o teste de galactomanana em amostras de pacientes com quadros clínicos distintos, porém com suspeita e/ou com comprovada AI, bem como as atuais tendências de conhecimento, aplicação e utilidade do ensaio laboratorial.


Invasive fungal diseases represent an increasing problem in the hospital environments, predominantly in the last two decades. The invasive aspergillosis (IA), induced by Aspergillus species, has been the main cause of death in severely immunocompromised patients, with mortality varying from 70 to 90%. Difficulties are found for diagnosing the IA. In vitro culture of biological material shows low sensitivity (<50%), besides the positivity usually occurs at the advanced stages of the infection. The test for detecting galactomannan has been the object of the present study, seeing that it represents a promising diagnostic tool, as a fast and non-invasive serological procedure. The objective of the present review is to survey the studies which have been performed by using methods for detecting galactomannan in samples from patients with distinct clinical pictures. Patients presenting suspicion and/or confirmed IA were also included, as well as the up-to-date trends in knowledge, application and utility of the test.


Assuntos
Aspergilose Pulmonar Invasiva/diagnóstico , Galactanos/análise , Mananas/análise , Técnicas e Procedimentos Diagnósticos
2.
R. Inst. Adolfo Lutz ; 77: e1749, 2018. tab
Artigo em Português | VETINDEX | ID: vti-24670

RESUMO

As doenças fúngicas invasivas têm sido um problema crescente em ambientes hospitalares, sobretudo nas últimas duas décadas. A aspergilose invasiva (AI), ocasionada pelo gênero Aspergillus, está entre as principais causas de morte em pacientes gravemente imunocomprometidos, com mortalidade que varia de 70 a 90%. O padrão de referência para o diagnóstico de AI é o cultivo do micro-organismo e a análise histopatológica dos órgãos afetados. Estes procedimentos são dificilmente realizados na maioria dos casos, e apresentam baixa sensibilidade (<50%), além de as amostras serem habitualmente obtidas em estados avançados da infecção. O teste de detecção de galactomanana tem sido objeto de estudo para o diagnóstico de AI, por representar uma promissora ferramenta e por ser uma técnica sorológica rápida e não invasiva. A presente revisão tem por objetivo fazer levantamento de estudos que utilizaram o teste de galactomanana em amostras de pacientes com quadros clínicos distintos, porém com suspeita e/ou com comprovada AI, bem como as atuais tendências de conhecimento, aplicação e utilidade do ensaio laboratorial.(AU)


Invasive fungal diseases represent an increasing problem in the hospital environments, predominantly in the last two decades. The invasive aspergillosis (IA), induced by Aspergillus species, has been the main cause of death in severely immunocompromised patients, with mortality varying from 70 to 90%. Difficulties are found for diagnosing the IA. In vitro culture of biological material shows low sensitivity (<50%), besides the positivity usually occurs at the advanced stages of the infection. The test for detecting galactomannan has been the object of the present study, seeing that it represents a promising diagnostic tool, as a fast and non-invasive serological procedure. The objective of the present review is to survey the studies which have been performed by using methods for detecting galactomannan in samples from patients with distinct clinical pictures. Patients presenting suspicion and/or confirmed IA were also included, as well as the up-to-date trends in knowledge, application and utility of the test.(AU)


Assuntos
Aspergilose Pulmonar Invasiva/diagnóstico , Galactanos/análise , Mananas/análise , Técnicas e Procedimentos Diagnósticos
3.
Food Chem ; 223: 76-81, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28069126

RESUMO

Yacon (Smallanthus sonchifolius Poepp. & Endl.) roots are largely grown in Andean countries and have attracted recent interest due to their antioxidant and prebiotic effects. Yacon is typically consumed as a fruit due to its sweet taste and juiciness. The macromolecular properties of an aqueous extract of yacon are investigated using asymmetric flow field-flow fractionation (AF4) coupled to UV, multiangle light scattering (MALS) and differential refractive index (dRI) detection. The method allows for determination of molar mass and size over the size distribution. Three major populations were found of which one strongly dominates in concentration. Through collection of fractions from AF4, carbohydrate composition and glycosidic linkage analysis for the dominating population was performed. The results show that the dominating population consists of a highly branched arabinogalactan (type 2) with a molar mass of approximately 1-2·105g/mol, a hydrodynamic radius of approximately 6-10nm and a relatively high apparent density (approx. 70-150kg/m3).


Assuntos
Galactanos/análise , Galactanos/química , Extratos Vegetais/análise , Extratos Vegetais/química , Raízes de Plantas/química , Antioxidantes/análise , Antioxidantes/química , Asteraceae , Fracionamento por Campo e Fluxo/métodos , Prebióticos/análise , Solubilidade , Água/química
4.
Int J Mol Sci ; 13(1): 961-976, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22312297

RESUMO

Sulfated polysaccharides (SP) are found mainly in seaweeds and animals. To date, they have only been found in six plants and all inhabit saline environments. Furthermore, there are no reports of SP in freshwater or terrestrial plants. As such, this study investigated the presence of SP in freshwaters Eichhornia crassipes, Egeria densa, Egeria naja, Cabomba caroliniana, Hydrocotyle bonariensis and Nymphaea ampla. Chemical analysis identified sulfate in N. ampla, H. bonariensis and, more specifically, E. crassipes. In addition, chemical analysis, FT-IR spectroscopy, histological analysis, scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDXA), as well as agarose gel electrophoresis detected SP in all parts of E. crassipes, primarily in the root (epidermis and vascular bundle). Galactose, glucose and arabinose are the main monosaccharides found in the sulfated polysaccharides from E. crassipes. In activated partial thromboplastin time (APTT) test, to evaluate the intrinsic coagulation pathway, SP from the root and rhizome prolonged the coagulation time to double the baseline value, with 0.1 mg/mL and 0.15 mg/mL, respectively. However, SP from the leaf and petiole showed no anticoagulant activity. Eichornia SP demonstrated promising anticoagulant potential and have been selected for further studies on bioguided fractionation; isolation and characterization of pure polysaccharides from this species. Additionally in vivo experiments are needed and are already underway.


Assuntos
Eichhornia/metabolismo , Galactanos/análise , Polissacarídeos/química , Sulfatos/química , Anticoagulantes/análise , Anticoagulantes/química , Eletroforese em Gel de Ágar , Galactanos/química , Galactanos/metabolismo , Microscopia Eletrônica de Varredura , Tempo de Tromboplastina Parcial , Espectroscopia de Infravermelho com Transformada de Fourier , Tromboplastina/química , Tromboplastina/metabolismo
5.
BMC Complement Altern Med ; 11: 58, 2011 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-21787425

RESUMO

BACKGROUND: Mushroom polysaccharides have traditionally been used for the prevention and treatment of a multitude of disorders like infectious illnesses, cancers and various autoimmune diseases. Crude mushroom extracts have been tested without detailed chemical analyses of its polysaccharide content. For the present study we decided to chemically determine the carbohydrate composition of semi-purified extracts from 2 closely related and well known basidiomycete species, i.e. Agaricus bisporus and A. brasiliensis and to study their effects on the innate immune system, in particular on the in vitro induction of pro-inflammatory cytokines, using THP-1 cells. METHODS: Mushroom polysaccharide extracts were prepared by hot water extraction and precipitation with ethanol. Their composition was analyzed by GC-MS and NMR spectroscopy. PMA activated THP-1 cells were treated with the extracts under different conditions and the production of pro-inflammatory cytokines was evaluated by qPCR. RESULTS: Semi-purified polysaccharide extracts of A. bisporus and A. brasiliensis (= blazei) were found to contain (1→6),(1→4)-linked α-glucan, (1→6)-linked ß-glucan, and mannogalactan. Their proportions were determined by integration of 1H-NMR signs, and were considerably different for the two species. A. brasiliensis showed a higher content of ß-glucan, while A. bisporus presented mannogalactan as its main polysaccharide. The extracts induced a comparable increase of transcription of the pro-inflammatory cytokine genes IL-1ß and TNF-α as well as of COX-2 in PMA differentiated THP-1 cells. Pro-inflammatory effects of bacterial LPS in this assay could be reduced significantly by the simultaneous addition of A. brasiliensis extract. CONCLUSIONS: The polysaccharide preparations from the closely related species A. bisporus and A. brasiliensis show major differences in composition: A. bisporus shows high mannogalactan content whereas A. brasiliensis has mostly ß-glucan. Semi-purified polysaccharide extracts from both Agaricus species stimulated the production of pro-inflammatory cytokines and enzymes, while the polysaccharide extract of A. brasiliensis reduced synthesis of these cytokines induced by LPS, suggesting programmable immunomodulation.


Assuntos
Agaricus/química , Produtos Biológicos/farmacologia , Fatores Imunológicos/farmacologia , Mediadores da Inflamação/metabolismo , Inflamação/prevenção & controle , Monócitos/efeitos dos fármacos , Polissacarídeos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/uso terapêutico , Linhagem Celular , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citocinas/genética , Citocinas/metabolismo , Galactanos/análise , Galactanos/farmacologia , Galactanos/uso terapêutico , Expressão Gênica/efeitos dos fármacos , Humanos , Fatores Imunológicos/análise , Fatores Imunológicos/uso terapêutico , Inflamação/induzido quimicamente , Inflamação/metabolismo , Lipopolissacarídeos , Estrutura Molecular , Monócitos/metabolismo , Polissacarídeos/química , Polissacarídeos/uso terapêutico , beta-Glucanas/análise , beta-Glucanas/farmacologia , beta-Glucanas/uso terapêutico
6.
J Sci Food Agric ; 91(13): 2394-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21604279

RESUMO

BACKGROUND: Cooking time decreases when beans are soaked first. However, the molecular basis of this decrease remains unclear. To determine the mechanisms involved, changes in both pectic polysaccharides and cell wall enzymes were monitored during soaking. Two cultivars and one breeding line were studied. RESULTS: Soaking increased the activity of the cell wall enzymes rhamnogalacturonase, galactanase and polygalacturonase. Their activity in the cell wall was detected as changes in chemical composition of pectic polysaccharides. Rhamnose content decreased but galactose and uronic acid contents increased in the polysaccharides of soaked beans. A decrease in the average molecular weight of the pectin fraction was induced during soaking. The decrease in rhamnose and the polygalacturonase activity were associated (r = 0.933, P = 0.01, and r = 0.725, P = 0.01, respectively) with shorter cooking time after soaking. CONCLUSION: Pectic cell wall enzymes are responsible for the changes in rhamnogalacturonan I and polygalacturonan induced during soaking and constitute the biochemical factors that give bean cell walls new polysaccharide arrangements. Rhamnogalacturonan I is dispersed throughout the entire cell wall and interacts with cellulose and hemicellulose fibres, resulting in a higher rate of pectic polysaccharide thermosolubility and, therefore, a shorter cooking time.


Assuntos
Culinária/métodos , Pectinas/metabolismo , Phaseolus/química , Sementes/química , Água/química , Parede Celular/enzimologia , Cotilédone/química , Cotilédone/enzimologia , Galactanos/análise , Galactanos/química , Galactose/análise , Glicosídeo Hidrolases/metabolismo , Peso Molecular , Pectinas/análise , Pectinas/química , Phaseolus/enzimologia , Proteínas de Plantas/metabolismo , Poligalacturonase/metabolismo , Ramnose/análise , Sementes/enzimologia , Solubilidade , Fatores de Tempo , Ácidos Urônicos/análise , beta-Galactosidase/metabolismo
7.
Braz J Biol ; 68(2): 367-71, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18660965

RESUMO

The influence of population density on some aspects of the reproductive biology of the snail Bradybaena similaris was studied. Molluscs were maintained under 0.2 (isolated), 0.3, 0.6, 1.0, 1.3 and 1.7 snail/m(2) densities. The animals maintained under 0.3 and 0.6 snail/m(2) showed the lowest numbers of eggs laid/snail, being the highest value observed to the 1.7 snail/m(2). The hatching of the snails maintained under 0.3 snail/m(2) density, begun at the 21st day after laying, and the maximum time required to the hatching was 36 days was observed to the eggs came from snails maintained under the densities 0.6, 1.0, 1.3 snail/m(2), respectively. The highest percentage hatchability (55.56%) was observed to isolated snails. The galactogen content in the albumen gland did not seem to accompany the alterations occurred in the reproduction of B. similaris in response to the different population densities.


Assuntos
Galactanos/análise , Oviposição/fisiologia , Caramujos/fisiologia , Animais , Feminino , Densidade Demográfica , Reprodução/fisiologia , Caramujos/anatomia & histologia
8.
Braz. j. biol ; 68(2): 367-371, May 2008. graf, tab
Artigo em Inglês | LILACS | ID: lil-486762

RESUMO

The influence of population density on some aspects of the reproductive biology of the snail Bradybaena similaris was studied. Molluscs were maintained under 0.2 (isolated), 0.3, 0.6, 1.0, 1.3 and 1.7 snail/m² densities. The animals maintained under 0.3 and 0.6 snail/m² showed the lowest numbers of eggs laid/snail, being the highest value observed to the 1.7 snail/m². The hatching of the snails maintained under 0.3 snail/m² density, begun at the 21st day after laying, and the maximum time required to the hatching was 36 days was observed to the eggs came from snails maintained under the densities 0.6, 1.0, 1.3 snail/m², respectively. The highest percentage hatchability (55.56 percent) was observed to isolated snails. The galactogen content in the albumen gland did not seem to accompany the alterations occurred in the reproduction of B. similaris in response to the different population densities.


A influência da densidade populacional em alguns aspectos da biologia reprodutiva do molusco Bradybaena similaris foi estudada. Os moluscos foram mantidos em densidades de 0.2 (isolados), 0.3, 0.6, 1.0,1.3 e 1.7 moluscos/m². Nas densidades de 0.3 e 0.6 moluscos/m², os moluscos apresentaram os menores números de ovos postos por molusco, sendo o maior valor observado para essa variável na densidade de 1.7 molusco/m². A eclosão dos moluscos mantidos a uma densidade de 0.3 molusco/m², iniciou-se aos 21 dias após a postura, sendo o tempo máximo necessário para a eclosão 36 dias para ovos oriundos de moluscos mantidos nas densidades de 0.6, 1.0, 1.3 moluscos/m². O maior percentual de eclosão (55.56 por cento) foi observado para os moluscos isolados. O conteúdo de galactogênio na glândula de albúmem parece não acompanhar as alterações na reprodução de B. similaris em resposta a diferentes densidades populacionais.


Assuntos
Animais , Feminino , Galactanos/análise , Oviposição/fisiologia , Caramujos/fisiologia , Densidade Demográfica , Reprodução/fisiologia , Caramujos/anatomia & histologia
9.
Z Naturforsch C J Biosci ; 62(9-10): 623-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18069232

RESUMO

A polysaccharide separated from Paecilomyces sp. was determined by gel permeation chromatography to be homogeneous. HPLC showed a monosaccharide containing D-glucose and D-fructose at a ratio of about 2:1. The results obtained from IR, 1H NMR, and 13C NMR analyses confirmed the proposed structure.


Assuntos
Paecilomyces/química , Polissacarídeos/química , Cromatografia em Gel , Galactanos/análise , Hidrólise , Espectroscopia de Ressonância Magnética , Polissacarídeos/isolamento & purificação , Solanum tuberosum/química , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Int J Biol Macromol ; 41(3): 324-31, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17531313

RESUMO

Commercial guar gum (GG) was purified by four different methods and characterized by gel permeation chromatography (GPC), thermogravimetric analysis and the determination of monosaccharides composition, protein and copper content, turbidity, intrinsic viscosity and rheological parameters. The first method was based on enzymatic hydrolysis with porcine pancreatin. In the second method successive gum dissolution, centrifugation and precipitation with acetone and ethanol were carried out. Precipitation with Fehling solution was employed in the third method. In the fourth method, the gum was purified by method 2 and then by method 3. All methods led to a reduction in protein content, arabinose and glucose residues, considered as sugar contaminants, and also in intrinsic viscosity and molar mass. Total elimination of protein was only achieved by method 4. Using methods 3 and 4, the gum was contaminated with small amounts of Cu(II) from the Fehling solution. Methods 2 and 4 apparently provided purer guar gum. If the amount of protein is a crucial parameter in the biological application and the guar will be taken in low amounts, method 4 is recommended. Taking into account the purity, thermal stability, rheological parameters of the purified gum and also the cost and simplicity of the procedure, method 2 has wider biological application.


Assuntos
Galactanos/análise , Galactanos/isolamento & purificação , Mananas/análise , Mananas/isolamento & purificação , Gomas Vegetais/análise , Gomas Vegetais/isolamento & purificação , Cobre/análise , Galactanos/química , Mananas/química , Gomas Vegetais/química , Proteínas/análise
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