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1.
J Am Coll Nutr ; 40(6): 502-516, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33606612

RESUMO

OBJECTIVE: It was aimed at comparing the glycating capacities of glucose and ribose in bovine serum albumin (BSA) and anti-glycation activity of pomegranate mesocarp extract (PME). The protective mechanism of PME against ribosylated BSA (BSARIB)-induced toxicity was also investigated. METHODS: BSA was incubated with glucose or ribose in the presence or absence of PME for 15 days. In preadipocytes pretreated with PME, cell viability, ROS production, lipid peroxidation and mitochondrial membrane potential were investigated following 1, 6, 12, 18 and 24 h exposure to BSARIB. Nuclear translocation of NFκB was assessed at 1 h and 24 h of BSARIB insult. Accumulation of oxidized proteins, activities of intrinsic antioxidant enzymes and IL-6 secretion were also determined after 24 h exposure to BSARIB. RESULTS: Ribose was a harsher glycating agent as compared to glucose and PME showed strong anti-glycation activity by suppressing (P < 0.05) the increase in levels of fluorescent AGEs, Amadori products, protein carbonyl and advanced oxidation protein products (AOPP). In preadipocytes, BSARIB potentiated pro-apoptotic activity by inhibiting the nuclear translocation of NFκB. BSARIB induced a time dependent decrease in cell viability, which was significantly suppressed (P < 0.05) by PME. The extract also significantly reduced (P < 0.05) the time dependent increase in ROS level and associated lipid peroxidation as well as loss in mitochondrial membrane potential caused by BSARIB. PME also counteracted the BSARIB-induced accumulation of oxidized proteins, decrease in intrinsic antioxidant activity and IL-6 over-secretion. CONCLUSIONS: PME showed anti-glycation activity and afforded protection against BSARIB-induced toxicity, oxidative stress and inflammation in preadipocytes.


Assuntos
Lythraceae , Punica granatum , Antioxidantes/farmacologia , Peroxidação de Lipídeos , Soroalbumina Bovina/metabolismo , Soroalbumina Bovina/toxicidade
3.
Appl Opt ; 56(35): 9663-9675, 2017 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-29240111

RESUMO

Original waveforms and optimized signal processing are proposed for frequency-modulated continuous-wave lidar for range finding, velocimetry, and laser anemometry. For range finding, the aim of this signal processing is to extend lidar range and reduce ambiguities. Moreover, the effect of moderate atmospheric turbulence on lidar efficiency is analyzed for infinite and finite targets, taking into account wind-induced bistatism. For laser anemometry, the aim is to measure air speed at the shortest distance farther than the rotor-induced turbulent volume around the helicopter and to avoid parasitic echoes coming from clouds or hard targets in the vicinity of a helicopter.

4.
Appl Opt ; 56(35): 9676-9685, 2017 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-29240112

RESUMO

Frequency-modulated continuous-wave lidar is evaluated for range finding, velocimetry, and laser anemometry. An original signal processing and waveform calibration for range finding leads to a reduction of computational effort while preserving capability for long-range measurement. Multiple target distance measurement is also demonstrated. For laser anemometry, the aim is to avoid parasitic echoes in the vicinity of a helicopter and to measure the air speed at the shortest distance farther than the rotor-induced turbulent volume around the helicopter. Flight tests of this functionality and vortex ring state warning are demonstrated.

5.
Food Funct ; 8(11): 4194-4209, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29043349

RESUMO

This study aimed at investigating and comparing the anti-diabetic potential of black and green teas. Biochemical analyses indicate higher antioxidant potency, significantly correlated with the phytochemicals present, in green teas compared to black teas. Both extracts afforded a similar level of protection to erythrocytes against peroxyl radical-induced lysis. Non-cytotoxic concentration of green and black tea extracts significantly reduced the reactive oxygen species (ROS) production (P < 0.01), lowered the oxidation of proteins (P < 0.05) and decreased the IL-6 secretion (P < 0.01) induced by AGEs or H2O2 in 3T3-L1 preadipocytes. Both teas also inhibited the decline in the enzymatic activities of superoxide dismutase, catalase and glutathione peroxidase induced by the pro-oxidants. The teas further suppressed the glycation of BSA mediated by glucose, ribose and MGO by reducing fluorescent AGE, fructosamine, protein carbonyl and AOPP levels. Black and green teas also inhibited the activities of α-amylase (AA50: 589.86 ± 39.51 and 947.80 ± 18.20 µg mL-1, respectively) and α-glucosidase (AA50: 72.31 ± 4.23 and 100.23 ± 8.10 µg mL-1, respectively). The teas afforded a comparable level of protection at the cellular level and against glycation while black tea exerted the highest carbohydrate hydrolysing enzymes inhibitory activity. Our results clearly show that black and green teas represent an important source of antioxidants with anti-diabetic potential.


Assuntos
Camellia sinensis/química , Diabetes Mellitus Tipo 2/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Hipoglicemiantes/farmacologia , Preparações de Plantas/farmacologia , Células 3T3 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/enzimologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Humanos , Interleucina-6/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , alfa-Amilases/química , alfa-Glucosidases/química
6.
Eur J Clin Nutr ; 67(9): 939-43, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23695204

RESUMO

BACKGROUND/OBJECTIVES: In sedentary adults, hydration is mostly influenced by total fluid intake and not by sweat losses; moreover, low daily fluid intake is associated with adverse health outcomes. This study aimed to model the relation between total fluid intake and urinary hydration biomarkers. SUBJECTS/METHODS: During 4 consecutive weekdays, 82 adults (age, 31.6±4.3 years; body mass index, 23.2±2.7 kg/m(2); 52% female) recorded food and fluid consumed, collected one first morning urine (FMU) void and three 24-h (24hU) samples. The strength of linear association between urinary hydration biomarkers and fluid intake volume was evaluated using simple linear regression and Pearson's correlation. Multivariate partial least squares (PLS) modeled the association between fluid intake and 24hU hydration biomarkers. RESULTS: Strong associations (|r| ≥ 0.6; P<0.001) were found between total fluid intake volume and 24hU osmolality, color, specific gravity (USG), volume and solute concentrations. Many 24hU biomarkers were collinear (osmolality versus color: r=0.49-0.76; USG versus color: r=0.46-0.78; osmolality versus USG: 0.86-0.97; P<0.001). Measures in FMU were not strongly correlated to intake. Multivariate PLS and simple linear regression using urine volume explained >50% of the variance in fluid intake volume (r(2)=0.59 and 0.52, respectively); however the error in both models was high and the limits of agreement very large. CONCLUSIONS: Hydration biomarkers in 24hU are strongly correlated with daily total fluid intake volume in sedentary adults in free-living conditions; however, the margin of error in the present models limits the applicability of estimating fluid intake from urinary biomarkers.


Assuntos
Biomarcadores/urina , Ingestão de Líquidos , Adulto , Índice de Massa Corporal , Desidratação , Feminino , Humanos , Modelos Lineares , Masculino , Análise Multivariada , Gravidade Específica , Equilíbrio Hidroeletrolítico
7.
Am J Gastroenterol ; 108(5): 786-95, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23588235

RESUMO

OBJECTIVES: The aim of the present pilot study was to evaluate the usefulness of a test meal containing lactulose in the non-invasive assessment of visceral sensitivity in irritable bowel syndrome (IBS), and to identify subsets of IBS patients based on gastrointestinal (GI) symptom generation. METHODS: We included 43 patients with IBS (Rome III) and 29 healthy controls. The fasted subjects were served three test meals consisting of a 400-ml liquid breakfast alone or containing lactulose (15 or 25 g) in a double-blind crossover design. Seven GI symptoms, overall digestive comfort, and exhaled H2/CH4 were assessed at baseline and every 15 min during 4 h after meal intake. Anxiety and depression were assessed only at baseline. A mapping of the seven GI symptoms was done using a Principal Component Analysis (4 h mean area under the curve, AUC). Independently, a hierarchical cluster analysis was performed on the same parameters to identify GI symptom-based IBS clusters. RESULTS: All three tests were well tolerated. The 25 g lactulose challenge enabled discrimination of IBS from healthy controls according to the symptom response. This challenge also enabled clustering of IBS subjects in two subgroups based mainly on bloating, distension, and discomfort symptoms (2,457 (2,043-2,872), 2,450 (1,910-2,990), 2,602 (2,126-3,079) vs. 537 (383-691), 619 (458-780), 643 (432-854); 4 h mean AUC; P<0.0001), overall digestive comfort (1807 (1318-2295) vs. 3350 (2942-3758); 4 h mean AUC; P<0.0001), and anxiety at baseline (9.2 (7.0-11.5) vs. 5.5 (4.2-6.9); Hospital Anxiety and Depression scale anxiety mean scores; P=0.003). This clustering was independent of the Rome III subtype and the amount of exhaled H2/CH4. CONCLUSIONS: The lactulose challenge test seems to be a promising tool to assess visceral sensitivity in IBS, and to subgroup IBS patients based on their symptom pattern.


Assuntos
Testes Respiratórios , Alimentos Formulados , Fármacos Gastrointestinais , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/fisiopatologia , Lactulose , Dor Abdominal/etiologia , Adulto , Idoso , Ansiedade/diagnóstico , Análise por Conglomerados , Estudos Cross-Over , Depressão/diagnóstico , Método Duplo-Cego , Feminino , Flatulência/etiologia , Fármacos Gastrointestinais/administração & dosagem , Gastroenteropatias/complicações , Gastroenteropatias/fisiopatologia , Humanos , Síndrome do Intestino Irritável/psicologia , Lactulose/administração & dosagem , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Período Pós-Prandial , Valor Preditivo dos Testes , Índice de Gravidade de Doença
8.
Diabetes Metab ; 38(2): 171-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22349032

RESUMO

AIM: Albumin, a major protein in the blood circulation, can undergo increased glycation in diabetes. From recent studies, it has become evident that glycation has important implications for albumin actions and impact on cell functioning. This study compares the structural and functional properties of albumin glycated by glucose and methylglyoxal (MGO) with those of albumin purified from diabetic patients. METHODS: Human serum albumin (HSA) was purified from diabetic patients and control subjects using affinity chromatography, and oxidation parameters in various albumin preparations were determined. Tryptophan and 1-anilino-8-naphthalene sulphonic acid (ANSA) probe fluorescence, redox state, antioxidant and copper-binding capacities of the different preparations of albumin were also determined and compared. RESULTS: Occurrence of oxidative modifications was enhanced in albumin whether purified from diabetic patients, or glycated by glucose or MGO, after determination of their fructosamine and free thiol and amino group contents, carbonyl content and antioxidant activities. Whereas more quantitative changes in oxidative and structural parameters were observed in the glucose- and MGO-modified albumins, significant impairment of albumin function (free-radical-scavenging and copper-binding capacities) were demonstrated in the HSA purified from diabetics. These findings reveal different structural and functional features of diabetic HSA compared with in vitro models. CONCLUSION: This study provides new information supporting albumin as an important biomarker for monitoring diabetic pathophysiology. In addition, it reconfirms the influence of experimental conditions in which advanced glycation end-products (AGEs) are generated in tests designed to mimic the pathological conditions of diabetes.


Assuntos
Cromatografia/métodos , Desoxiglucose/química , Diabetes Mellitus/sangue , Glucose/química , Produtos Finais de Glicação Avançada/química , Albumina Sérica/química , Desoxiglucose/análogos & derivados , Glicosilação , Humanos , Espectrometria de Fluorescência
9.
Ann Bot ; 96(7): 1307-14, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16243851

RESUMO

BACKGROUND AND AIMS: Plastid NADP-dependent malate dehydrogenase (MDH) catalyses the conversion of oxaloacetate to malate. In C4 plants, it is involved in photosynthetic carbon assimilation. In Poaceae, one NADP-MDH gene has been identified in rice (C3; Erhartoideae) and maize (C4; Panicoideae), whereas two tandemly repeated genes have been identified in Sorghum (C4; Panicoideae). In the present study, the molecular evolution of the NADP-MDH multigene family was investigated in order to analyse how the C4 isoform has evolved over a broader range of panicoid grasses. METHODS: Polymerase chain reaction (PCR)-based cloning was used to isolate cDNAs encoding NADP-MDHs from 15 species of Panicoideae. A gene phylogeny was reconstructed based on cDNA sequences using distance and maximum parsimony methods. Episodic selection along some branches of the phylogenetic tree was tested by analysing non-synonymous and synonymous rate ratios. Transcription of NADP-MDH genes was compared in green leaves of five accessions of Saccharum, Sorghum and Vetiveria using a semi-quantitative PCR approach. KEY RESULTS: Phylogenetic analyses of these data support the existence of two NADP-MDH gene lineages (NMDH-I and NMDH-II) in several Andropogoneae (i.e. Saccharum, Sorghum and Vetiveria). Episodic positive selection was shown along the basal branch of the NMDH-II clade. Three amino acid modifications allow the two gene lineages to be distinguished, suggesting a positive selection at these sites. In green leaves, we showed that the transcript accumulation was higher for NMDH-I than for NMDH-II. CONCLUSIONS: It is hypothesized that the maintenance of both NADP-MDH genes in some Andropogoneae is due to a partition of the original functions across both copies. NMDH-I probably corresponds to the C4 isoform as previously suggested. Nevertheless, some C4 species (e.g. maize) only have one gene which should be selected for its high expression level in leaves. This study confirms that gene duplicates have been recruited for C4 photosynthesis but are not required in every case.


Assuntos
Malato Desidrogenase (NADP+)/genética , Poaceae/genética , Evolução Molecular , Duplicação Gênica , Família Multigênica , Mutação , Filogenia , Seleção Genética , Transcrição Gênica
10.
CANNT J ; 11(1): 36-9, 2001.
Artigo em Francês | MEDLINE | ID: mdl-11785320

RESUMO

The initial production of a poster and a document about a Hepatitis B vaccination protocol spurred the further development of a self-care guide for dialysis patients. The Hepatitis B vaccination document, which was an important tool for recording vaccination results, gave rise to a completely unexpected development. Based on feedback from the patients, all dialysis results eventually became integrated into a self-care guide. In this self-care guide, not only is general information for dialysis patients provided but also specific advice to promote continuity of care. Nurses play an important role in encouraging and developing the self-care abilities of patients. With case management, the nurse also plays an important role in health promotion for a group of patients. There are countless benefits for the targeted group. This self-care guide is intended to be a tool to provide information, to promote awareness, to aid follow-up and to prevent complications. Its goal is an improved state of health and wellbeing for dialysis patients.


Assuntos
Educação de Pacientes como Assunto , Diálise Renal , Autocuidado
13.
Hum Antibodies Hybridomas ; 2(4): 194-9, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1721552

RESUMO

The heterohybridoma cell line HBp2 secreting human monoclonal antibody (hMAb) directed against Bordetella pertussis was generated by fusing SP2/HPT heteromyeloma cells with human spleen lymphocytes, after in vitro stimulation for 6 days. The hybridoma was maintained in culture for more than 1 year with continuous antibody secretion. The hMAb HBp2, an IgM, reacted with untreated and proteinase K-treated B. pertussis outer membrane antigens, whereas the reactivity was lost when the antigen was treated with sodium periodate. Human MAb HBp2 was shown to be specific to B. pertussis LOS by immunoblotting of whole cell extracts after SDS-PAGE. In a dot enzyme immunoassay, HBp2 reacted with all B. pertussis strains and clinical isolates tested except for four atypical variant strains of the LOS B phenotype. Human MAb HBp2 also reacted with a clinical isolate of B. bronchiseptica. No reaction was observed against B. parapertussis and other gram-negative species. Together these studies suggested that HBp2 is reactive with carbohydrate epitopes present on the LOS A. Binding assays with live bacteria demonstrated that hMAb HBp2 reacted with cell surface exposed epitopes on B. pertussis but the antibody did not bind significantly to the surface on intact B. bronchiseptica cells. When examined for bactericidal activity in the presence of complement, hMAb HBp2 showed high lytic capability against B. pertussis while no killing was obtained against B. bronchiseptica. These experiments established that LOS A is a target for human bactericidal antibodies. This antigen merits further investigation as a potentially important component in human immunity to B. pertussis infection.


Assuntos
Anticorpos Monoclonais , Bordetella pertussis/imunologia , Lipopolissacarídeos/imunologia , Anticorpos Antibacterianos/biossíntese , Anticorpos Monoclonais/biossíntese , Citotoxicidade Celular Dependente de Anticorpos , Proteínas da Membrana Bacteriana Externa/imunologia , Epitopos , Humanos , Hibridomas/imunologia
14.
J Gen Microbiol ; 137(4): 905-11, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1713258

RESUMO

Spleen cells from mice immunized with a Bordetella pertussis N-lauroyl sarcosine membrane extract (SME) were used to generate hybridoma cells lines producing monoclonal antibodies (mAbs). Seven mAbs were shown to be specific to B. pertussis lipo-oligosaccharide (LOS) by immunoblotting of SME or purified LOS following SDS-PAGE. All mAbs reacted with the B. pertussis Tohama I strain of the LOS AB phenotype, and did not react with the atypical variant strain 134 of the LOS B phenotype. The immune reactivity of the mAbs was retained after treatment of SME with proteinase K and was lost after sodium periodate treatment. No cross-reactivity was observed with the mAbs when tested against B. parapertussis and other Gram-negative bacteria. However, all mAbs reacted with B. bronchiseptica. Binding assays with live B. pertussis cells demonstrated that mAbs strongly reacted with cell surface exposed antigenic determinants. High bacterial cell lytic capability was observed for five of these mAbs. Concentrations between 0.22 and 2.2 micrograms mAb ml-1 (0.1 and 1 microgram per 450 microliter assay) purified by protein A were required to kill at least 50% of the bacteria. Competition immunoassays with biotinylated antibodies showed that the bacteriolytic and non-bacteriolytic mAbs were directed to different epitopes of the B. pertussis LOS A.


Assuntos
Anticorpos Monoclonais/imunologia , Bordetella pertussis/imunologia , Lipopolissacarídeos/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Anticorpos Antibacterianos/farmacologia , Anticorpos Monoclonais/farmacologia , Especificidade de Anticorpos , Antígenos de Superfície/imunologia , Western Blotting , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Epitopos , Camundongos , Camundongos Endogâmicos BALB C
16.
Nouv Presse Med ; 10(22): 1813-5, 1981 May 16.
Artigo em Francês | MEDLINE | ID: mdl-7232170

RESUMO

Skin lesions in systemic candidiasis are erythematous maculopapules and maculonodules which appear at the onset of the septicaemic phase. Their presence, especially when associated with diffuse myalgia, suggest the diagnosis which must be confirmed by haemocultures, histological examination of the skin with PAS stain and culture of skin fragments in Sabouraud's medium. Systemic candidiasis with skin lesions seems to be mainly due to Candida tropicalis and to occur with great frequency in patients with underlying blood disease. Of the three cases reported here, one concerned a 24-year-old man with premyelocytic acute leukaemia, the second a 45-year-old woman with drug-induced agranulocytosis and the third one a man aged 25 admitted to hospital for peritonitis secondary to Crohn's disease.


Assuntos
Candidíase/diagnóstico , Sepse/diagnóstico , Dermatopatias/etiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sepse/complicações
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