Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Biomed Mater Res B Appl Biomater ; 103(3): 539-47, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24934473

RESUMO

Hemocompatibility of genistein-modified poly(ethersulfone)/poly(vinylpyrrolidone) (PES/PVP) hemodialysis (HD) membranes has been investigated in vitro with emphasis on evaluation of cell viability, antioxidant, anti-inflammatory, and antiplatelet adhesion properties. Genistein modified PES/PVP membranes reveal significant reduction of the reactive oxygen species and also considerable suppression of interleukin-1ß and tumor necrosis factor-α levels in whole blood, but to a lesser extent ininterleukin-6. The incorporation of PVP into the HD membrane reduces platelet adhesion by virtue of its hydrophilicity. Of particular importance is that platelet adhesion of the genistein modified membranes declines noticeably at low concentrations of genistein for about 5-10%, beyond which it raises the number of adhered platelets. The initial decline in the platelet adhesion is attributable to genistein's ability to inhibit intercellular and/or vascular cell adhesion, whereas the reversal of this adhesion trend with further increase of genistein loading is ascribed to the inherent hydrophobicity of the genistein modified HD membrane.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Materiais Biocompatíveis/farmacologia , Genisteína/farmacologia , Membranas Artificiais , Adesividade Plaquetária/efeitos dos fármacos , Polímeros/farmacologia , Povidona/farmacologia , Diálise Renal/instrumentação , Sulfonas/farmacologia , Anti-Inflamatórios/toxicidade , Antioxidantes/toxicidade , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/metabolismo , Genisteína/química , Genisteína/toxicidade , Humanos , Interações Hidrofóbicas e Hidrofílicas , Técnicas In Vitro , Interleucina-1beta/sangue , Interleucina-6/sangue , Teste de Materiais , Estrutura Molecular , Polímeros/química , Polímeros/toxicidade , Povidona/química , Povidona/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Sulfonas/química , Sulfonas/toxicidade , Fator de Necrose Tumoral alfa/análise
2.
J Phys Chem B ; 118(41): 11993-2001, 2014 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-25247624

RESUMO

By virtue of antioxidant and anti-inflammable properties, plant-derived phytochemicals such as mangiferin and genistein have attracted considerable attention for functionalization of polymeric hemodialysis (HD) membranes via solution blending. In-vitro dihydrorhodamine (DHR) assay of the genistein-modified membranes revealed drastic reduction in the level of the reactive oxygen species (ROS). In contrast, mangiferin-modified HD membrane manifested the pro-oxidant activity. We suspected that such difference in ROS generation may be attributed to the glucose unit on the xanthone backbone of mangiferin. This hypothesis was confirmed by comparing the ROS levels of genistein versus genistin, and mangiferin versus xanthone and 3,4,5,6-tetrahydroxyxanthone. Phytochemicals without the glucose unit show better antioxidant property related to the glycosides. Anti-inflammatory property was further conducted by measuring the level of TNF-α in blood after contacting with the same selected phytochemicals. Of particular interest is that the glucose unit promotes the generation of TNF-α.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glucose/farmacologia , Compostos Fitoquímicos/farmacologia , Anti-Inflamatórios/química , Antioxidantes/química , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/fisiologia , Membrana Celular/fisiologia , Sobrevivência Celular/fisiologia , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Genisteína/química , Genisteína/farmacologia , Humanos , Compostos Fitoquímicos/química , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/sangue , Xantonas/química , Xantonas/farmacologia
3.
Biomacromolecules ; 14(5): 1423-33, 2013 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-23594342

RESUMO

Genistein is a phytochemical with a broad range of desirable biological activity for wound healing. However, its poor bioavailability requires developing a new method for fabricating an appropriate carrier vehicle to deliver genistein in a sustained manner. Based on the guidance afforded by the ternary phase diagram of poly(D,L-lactic acid) (PDLLA), poly(ethylene oxide) (PEO), and genistein blends, certain selective compositions were electrospun. We obtained a uniformly smooth surface morphology in unmodified and genistein-modified PEO/PDLLA fibers, documented by scanning electron microscopy. Moreover, wide-angle X-ray diffraction and 1H NMR studies revealed that the genistein molecules, successfully incorporated in the blends, remained chemically stable after electrospinning. Besides surface wettability and dimensional stability of the electrospun mats, the released genistein amount has been evaluated as a function of PEO concentration. Our biocompatibility investigations suggest that genistein-modified PEO/PDLLA electrospun mats exhibit strong antioxidant and anti-inflammatory activities which indicate they have potential applications for wound dressings.


Assuntos
Anti-Inflamatórios/química , Antioxidantes/química , Materiais Biocompatíveis/síntese química , Preparações de Ação Retardada/síntese química , Genisteína/química , Ácido Láctico/química , Polímeros/química , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Bandagens , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Preparações de Ação Retardada/farmacologia , Técnicas Eletroquímicas , Genisteína/farmacologia , Humanos , Cinética , Ácido Láctico/farmacologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Microscopia Eletrônica de Varredura , Poliésteres , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Polímeros/farmacologia , Molhabilidade , Cicatrização
4.
Biomacromolecules ; 12(7): 2447-55, 2011 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-21657246

RESUMO

Genistein-modified poly(amide):poly(vinyl pyrrolidone) (PA:PVP/G) hemodialysis membranes have been fabricated by coagulation via solvent (dimethyl sulfoxide, DMSO)/nonsolvent (water) exchange. The antioxidant and anti-inflammatory properties of the unmodified PA:PVP membranes were evaluated in vitro using human blood. It was found that these unmodified PA:PVP membranes were noncytotoxic to peripheral blood mononuclear cells (PBMC) but raised intracellular reactive oxygen species (ROS) levels. Pure genistein (in DMSO solution) was not only nontoxic to PBMC, but also suppressed the ROS levels in a manner dependent on genistein dosage. A similar dose-dependent suppression of ROS was found in genistein-modified PA (i.e., PA/G) membranes. However, the PVP addition had little or no effect in the suppression of ROS levels for the ternary PA:PVP/G system; the membrane ROS suppression was largely controlled by the genistein dosage. The levels of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin (IL-6) in whole blood were measured by ex vivo stimulation with lipopolysaccharide (LPS). The unmodified PA:PVP membranes drastically increased the level of TNF-α; however, the concentration of IL-1ß and IL-6 remained almost the same. The PA/G membranes reduced the concentration of IL-1ß and TNF-α even at very low genistein loadings, but it required a higher genistein loading to realize a similar effect in the case of IL-6. Of particular importance is that the genistein-modified blend membranes (PA:PVP/G) showed greater suppression of the concentrations of all three cytokines (TNF-α, IL-1ß, and IL-6) in comparison with those of the PA/G membranes, signifying the role of PVP in the enhanced anti-inflammatory properties of these genistein-modified membranes. Ultraviolet-visible (UV-vis) spectroscopy was employed to quantify any genistein leaching during the in vitro testing.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Genisteína/farmacologia , Membranas Artificiais , Diálise Renal , Anti-Inflamatórios não Esteroides/química , Antioxidantes/química , Sobrevivência Celular/efeitos dos fármacos , Genisteína/química , Humanos , Leucócitos Mononucleares , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície
5.
J Trauma ; 67(5): 968-74, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19901656

RESUMO

BACKGROUND: Aging is associated with a decline in immune function. This may contribute to decreased ability of an elderly patient to mount an appropriate innate inflammatory response when injured. This study examined elderly trauma patients to determine whether there was a difference in neutrophil response to injury when compared with controls. METHODS: This prospective, observational, cohort study compared neutrophil function in 24 injured elderly (older than 65 years) patients admitted to our trauma center to control groups of noninjured individuals (11 elderly and 17 young). Blood samples were also taken from the injured elderly group within 48 hours of trauma and subsequently at two periods during their hospital stay. A single blood sample was obtained from the noninjured control groups. Neutrophils were analyzed for CD18 expression, stimulated oxidative burst, apoptosis, and IL-10. Results were compared using one-way analysis of variance (alpha 0.05). This study was approved by the Institutional Review Board. RESULTS: Twenty-four injured elderly subjects were enrolled: mean injury severity score 15.3, average age 74.6 years, 92% survival, 100% blunt trauma. CD18 levels in the elderly injured subjects for all three time periods were significantly higher than both control groups. When evaluated between controls, CD18 for the noninjured elderly (NIE) was also significantly higher than the noninjured young (NIY). The neutrophil stimulated oxidative burst in the injured elderly subjects at time periods 1, 2, and 3 was not significantly different from the NIY controls. However, the injured elderly had a significantly higher oxidative burst at time period 3 than the NIE controls. Apoptosis in the injured elderly subjects was significantly lower in all three time periods than the NIY. There was no difference in apoptosis between the injured elderly subjects when compared with the NIE controls. There was no significant difference in IL-10 expression among groups. CONCLUSION: Injury results in differences in innate immune function in the elderly when compared with controls. The clinical significance of this is uncertain and warrants further investigation.


Assuntos
Imunidade Inata/imunologia , Neutrófilos/imunologia , Ferimentos não Penetrantes/imunologia , Idoso , Anexina A5/metabolismo , Apoptose/fisiologia , Antígenos CD18/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Escala de Gravidade do Ferimento , Interleucina-10/sangue , Masculino , Projetos Piloto , Estudos Prospectivos , Explosão Respiratória/fisiologia
6.
Ann N Y Acad Sci ; 1173: 186-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19758149

RESUMO

Antibodies to gliadin and tissue transglutaminase (TTG) are associated with celiac disease. Celiac patients often present with low hemoglobin levels; however, the incidence of celiac disease in patients with low hemoglobin levels is unknown. We investigated the incidence of celiac disease-associated antibodies in plasma obtained from individuals with low and normal hemoglobin levels. Our objective was to determine if antigliadin and anti-TTG antibodies are more prevalent in individuals with low hemoglobin levels than in control subjects with normal hemoglobin levels. Following IRB approval, we obtained 86 plasma specimens with hemoglobin levels less than or equal to 10 g/dL and 88 plasma specimens from individuals with hemoglobin levels greater than or equal to 13 g/dL. IgA and IgG antibodies to gliadin and TTG were determined by ELISA assays provided by BioRad, Inc. IgG antigliadin Ab was present in 6 out of 86 low hemoglobin specimens and in two of the normal hemoglobin specimens. The IgA antigliadin ELISA assay was positive in 19 out of 86 low hemoglobin specimens and in 21 out of 88 normal hemoglobin specimens. IgA anti-TTG was detected in 9 out of 86 low hemoglobin specimens and in 3 out of 88 normal hemoglobin specimens. IgG anti-TTG was not present in any of the specimens. IgA antibodies to TTG were more prevalent in individuals with low hemoglobin levels. The incidence of IgG anti-TTG and IgG and IgA antibodies to gliadin was not related to plasma hemoglobin levels in our sample.


Assuntos
Autoanticorpos/sangue , Doença Celíaca/sangue , Hemoglobinas/metabolismo , Doença Celíaca/diagnóstico , Doença Celíaca/imunologia , Ensaio de Imunoadsorção Enzimática , Proteínas de Ligação ao GTP , Gliadina/imunologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Proteína 2 Glutamina gama-Glutamiltransferase , Transglutaminases/imunologia , Globinas beta
7.
Diagn Microbiol Infect Dis ; 55(4): 327-31, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16626911

RESUMO

The emergence of macrolide- and lincosamide-resistant Streptococcus pneumoniae is a worldwide concern. Of particular interest is the increasing prevalence of erythromycin and clindamycin-resistant isolates containing both erm(B) and mef genes. This study determined the prevalence of erythromycin and clindamycin resistance in 596 clinical S. pneumoniae isolates from 2 adult tertiary care hospitals over a 4-year period (2001-2004). Erythromycin resistance increased from 24% to 34%, but S. pneumoniae isolates resistant to clindamycin as well as to erythromycin increased from 3% in 2001 to 15.5% in 2004 (5-fold increase). Among erythromycin-resistant isolates, those also resistant to clindamycin (MLS(B) phenotype) increased 3-fold (12.8-45%). Of forty-one erythromycin/clindamycin-resistant S. pneumoniae isolates tested, 29 (71%) contained both erm(B) and mef(E) genes. Pulsed-field gel electrophoresis performed on 28 erm(B) + mef(E) positive isolates identified 2 predominant and possibly related clones, which made up 64% of the isolates.


Assuntos
Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Proteínas de Membrana/genética , Metiltransferases/genética , Streptococcus pneumoniae/genética , Clindamicina/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Eritromicina/uso terapêutico , Humanos , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/crescimento & desenvolvimento , Estados Unidos
8.
Anal Quant Cytol Histol ; 26(6): 323-30, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15678614

RESUMO

OBJECTIVE: To establish whether the results of quantitative evaluation of estrogen receptors (ERs) in cytologic fine needle aspiration (FNA) biopsies of the breast are comparable to the results obtained on excised breast tumors and therefore suitable for making a clinical decision on tamoxifen treatment in women who are not candidates for surgery. STUDY DESIGN: We performed a retrospective review of 118 breast FNA specimens that were positive for adenocarcinoma cells, had adequate cell block cellularity and provided subsequent surgical resection tissue. Quantification of ERs was performed on cell block material and follow-up tissue sections by the Chromavision Automated Imaging System, San Juan Capistrano, California, U.S.A. RESULTS: Quantitative image analysis provided consistently reliable, comparable results when evaluating for the presence or absence of ERs (at a 5% staining cutoff level), with 98.3% agreement between FNA cytology and histology specimens. Quantitative measurements of FNA samples showed the best agreement with the values derived from the subsequent surgical specimens at high-end (> 85% staining) and low-end (< 10% staining) values. However, a direct linear correlation of values was not observed. In the great majority of parallel measures, ERs were either strongly positive (> 75% staining) or had a zero value, particularly in the surgical specimens, with more "in-between" values identified in FNA specimens. CONCLUSION: Quantitative image analysis of FNA of ER results are comparable to those of surgical excision specimens and can be used for therapeutic decision making. The utility and advantages of quantitative ERs by image analysis include providing the patient and physician with important early prognostic and diagnostic information before planning a surgical approach. Additionally, FNA ERs are useful in determining therapy alternatives in patients who are not surgical candidates and in evaluating the preoperative hormone status of patients receiving chemotherapy prior to surgery.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Processamento de Imagem Assistida por Computador , Receptores de Estrogênio/metabolismo , Adenocarcinoma/patologia , Biópsia por Agulha Fina , Neoplasias da Mama/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Ohio , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...