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1.
Nutrition ; 65: 18-26, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31029917

RESUMO

OBJECTIVE: Intrauterine and postnatal micronutrient malnutrition may program metabolic diseases in adulthood. We examined whether moderate zinc restriction in male and female rats throughout fetal life, lactation, or postweaning growth induces alterations in liver, adipose tissue, and intermediate metabolism. METHODS: Female Wistar rats were fed low-zinc or control zinc diets from pregnancy to offspring weaning. After weaning, male and female offspring were fed either a low-zinc or a control zinc diet. At 74 d of life, oral glucose tolerance tests were performed and serum metabolic profiles were evaluated. Systolic blood pressure and oxidative stress and morphology of liver and retroperitoneal adipose tissue were evaluated in 81 d old offspring. RESULTS: Zinc restriction during prenatal and postnatal life induced an increase in systolic blood pressure, hyperglycemia, hypertriglyceridemia, higher serum glucose levels at 180 min after glucose overload, and greater insulin resistance indexes in male rats. Hepatic histologic studies revealed no morphologic alterations, but an increase in lipid peroxidation and catalase activity were identified in zinc-deficient male rats. Adipose tissue from zinc-deficient male rats had adipocyte hypertrophy, an increase in lipid peroxidation, and a reduction in catalase and glutathione peroxidase activity. Adequate dietary zinc content during postweaning growth reversed basal hyperglycemia, hypertriglyceridemia, insulin resistance indexes, hepatic oxidative stress, and adipocyte hypertrophy. Female rats were less sensitive to the metabolic effects of zinc restriction. CONCLUSIONS: This study strengthens the importance of a balanced intake of zinc during growth to ensure adequate lipid and carbohydrate metabolism in adult life.


Assuntos
Exposição Materna/efeitos adversos , Doenças Metabólicas/metabolismo , Complicações na Gravidez/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Zinco/deficiência , Animais , Suplementos Nutricionais , Feminino , Feto/metabolismo , Lactação/metabolismo , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Doenças Metabólicas/etiologia , Gravidez , Complicações na Gravidez/etiologia , Efeitos Tardios da Exposição Pré-Natal/etiologia , Ratos , Ratos Wistar , Fatores Sexuais , Desmame , Zinco/administração & dosagem
2.
PLoS One ; 12(3): e0172900, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28257515

RESUMO

INTRODUCTION: The immune system acts on different metabolic tissues that are implicated in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Leptin and linoleic acid have the ability to potentially affect immune cells, whereas curcumin is a known natural polyphenol with antioxidant and anti-inflammatory properties. AIMS: This study was designed to evaluate the pro-inflammatory and pro-oxidant effects of leptin and linoleic acid on immune cells from patients with NAFLD and to corroborate the modulatory effects of curcumin and its preventive properties against the progression of NAFLD using a high-fat diet (HFD)-induced NAFLD/nonalcoholic steatohepatitis mouse model. RESULTS: The ex vivo experiments showed that linoleic acid increased the production of reactive oxygen species in monocytes and liver macrophages, whereas leptin enhanced tumor necrosis factor-α (TNF-α) production in monocytes and interferon-γ production in circulating CD4+ cells. Conversely, oral administration of curcumin prevented HFD-induced liver injury, metabolic alterations, intrahepatic CD4+ cell accumulation and the linoleic acid- and leptin- induced pro-inflammatory and pro-oxidant effects on mouse liver macrophages. CONCLUSION: Our findings provide new evidence for the therapeutic potential of curcumin to treat human NAFLD. However, the development of a preventive treatment targeting human circulating monocytes and liver macrophages as well as peripheral and hepatic CD4+ cells requires additional research.


Assuntos
Antioxidantes/administração & dosagem , Curcumina/administração & dosagem , Fígado/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Leptina/administração & dosagem , Ácido Linoleico/administração & dosagem , Fígado/metabolismo , Fígado/patologia , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Espécies Reativas de Oxigênio/metabolismo
3.
Acta bioquím. clín. latinoam ; Acta bioquím. clín. latinoam;50(4): 575-581, dic. 2016. graf, tab
Artigo em Espanhol | LILACS | ID: biblio-837631

RESUMO

El objetivo del trabajo fue evaluar si la reducción de adiponectina (ADP) en el síndrome metabólico (SMet), influencia las características aterogénicas de VLDL. Se estudiaron 45 pacientes con SMet y 15 controles sanos. En suero en ayunas se midió perfil lipídico, ácidos grasos libres (AGL), ADP, se aisló VLDL (d<1,006 g/L) caracterizándola en su composición química y tamaño (HPLC-exclusión molecular). En plasma post-heparínico se determinó la actividad de lipoproteína lipasa (LPL). En SMet VLDL mostró incremento de masa, número de partículas, contenido en triglicéridos-VLDL y mayor proporción de VLDL grandes (p<0,05). El incremento de AGL correlacionó con la masa de VLDL (r=0,36; p=0,009), número de partículas-VLDL (r=0,45; p=0,0006) y %-VLDL grandes (r=0,32; p=0,02). SMet mostró descenso en ADP (7,4±4,8 vs. 15,5±7,2 μg/mL, p=0,01) y en actividad de LPL (p=0,01), que correlacionaron entre si (r=0,38; p=0,01; ajustado por HOMA-IR y cintura: β=0,35; p=0,02). ADP correlacionó negativamente con AGL y %-VLDL grandes (p<0,03). Se concluye que en SMet la disminución de ADP favorecería la secreción de VLDL sobre-enriquecidas en triglicéridos y de mayor tamaño, y además retardaría el catabolismo de VLDL mediado por LPL, resultando en la acumulación de VLDL alteradas en circulación con características aterogénicas.


The aim of the work was to evaluate whether the reduction of adiponectin (ADP) in metabolic syndrome (MetS) affects the atherogenic features of VLDL. A total of 45 patients with MetS (ATPIII) and 15 healthy controls were studied. In fasting serum, lipid profile, free fatty acids (FFA) and ADP were determined. VLDL was isolated (d<1.006 g/L) and characterized in chemical composition and size (size exclusion-HPLC). In post-heparin plasma, lipoprotein lipase (LPL) activity was measured. In MetS, VLDL showed increased total mass, particle number, VLDL-triglyceride content and higher large-VLDL proportion (p<0.05). The increase in FFA correlated with VLDL mass (r=0.36; p=0.009), VLDL particle number (r=0.45; p=0.0006) and large-VLDL proportion (r=0.32; p=0.02). MetS patients showed a decrease in ADP (7.4±4.8 vs. 15.5±7.2 μg/mL, p=0.01) and in LPL activity (p=0.01), that positively correlated between them (r=0.38; p=0.01; adjusted by HOMA-IR and waist: β=0.35; p=0.02). ADP inversely correlated with FFA and large-VLDL% (p<0.03). It can be concluded that in MetS, decreased ADP would favour the secretion of triglyceride over-enriched and larger VLDL particles, and also would delay VLDL catabolism mediated by LPL, resulting in the accumulation of altered VLDL with atherogenic characteristics.


O objetivo do trabalho foi avaliar se a redução da adiponectina (ADP) na síndrome metabólica (SM), afeta as características aterogênicas das VLDL. Foram estudados 45 indivíduos com SM e 15 controles saudáveis. Em jejum, foi medido em soro o perfil lipídico, ácidos graxos livres (AGL) e ADP. Foram isoladas as VLDL (d <1,006 g / L) caracterizando-as em relação a sua composição química e tamanho (HPLC- exclusão molecular). No plasma pós-heparina foi medida a atividade da lipoproteína lipase (LPL). Em indivíduos com SM, as VLDL apresentaram aumento de massa, número de partículas, conteúdo de triglicerídeos -VLDL e maior proporção de VLDL grandes (p<0,05). O aumento de AGL correlacionou com a massa de VLDL (r=0,36; p=0,009), número de partículas -VLDL (r=0,45; p=0,0006) e percentual -VLDL grandes (r=0,32; p=0,02). A SM mostrou uma diminuição em ADP (7,4±4,8 vs. 15,5±7,2 μg/mL, p=0,01) e em atividade de LPL (p=0,01), que correlacionaram entre eles (r=0,38; p=0,01; ajustada por HOMA-IR e cintura: β=0,35; p=0,02). A ADP correlacionou em forma negativa com AGL e %-VLDL grandes (p<0,03). A conclusão é que em indivíduos com SM, a diminuição da ADP iria favorecer a secreção de VLDL super-enriquecidas em triglicerídeos e de maior tamanho, e também atrasaria o catabolismo das VLDL mediado por LPL, resultando na acumulação de VLDL alteradas em circulação com características aterogênicas.


Assuntos
Humanos , Masculino , Feminino , Triglicerídeos/análise , Síndrome Metabólica , Adiponectina , Ácidos Graxos não Esterificados , Lipase Lipoproteica
4.
Acta bioquím. clín. latinoam ; Acta bioquím. clín. latinoam;50(4): 629-634, dic. 2016.
Artigo em Espanhol | LILACS | ID: biblio-837635

RESUMO

LOX-1 es un receptor endotelial de la familia de las lectinas. Su actividad biológica tiene un fuerte impacto en los fenómenos inflamatorios, oxidativos y aterogénicos endoteliales. Cuando se conoció el receptor de la lipoproteína de baja densidad (RLDL) y su regulación, se afirmó el papel aterogénico del colesterol transportado en esta lipoproteína (C-LDL). Este papel de las lipoproteínas fue la base de la denominación de dislipoproteinemias en reemplazo de dislipemias. En condiciones post-prandiales, las lipoproteínas ricas en triglicéridos, como quilomicrones y lipoproteínas de muy baja densidad (VLDL), son degradadas por la lipoproteína lipasa (LPL) de la pared vascular, produciéndose remanentes de quilomicrones (RQ) y lipoproteínas de densidad intermedia (IDL), respectivamente, que en conjunto se denominan lipoproteínas remanentes (RLPs). Dependiendo del estrés oxidativo las RLPs son oxidables y pueden unirse al LOX-1. También se liberan ácidos grasos que injurian células endoteliales y contribuyen a abrir brechas en el endotelio, que en condiciones fisiológicas es una barrera de células con uniones estrechas. El dominio intracelular de LOX-1 regula el reconocimiento de lipoproteínas de baja densidad oxidadas (LDLOX) y de RLPs. Además, posee un efecto dependiente de los radicales reactivos de oxígeno (ROS). Su dominio transmembrana actúa en el pasaje de LDLOX y monocitos al subendotelio. La inhibición de LOX-1 con anticuerpos específicos impide su unión con LDLOX, restableciendo la barrera entre el lumen vascular y el subendotelio. En cambio, las LDLOX unidas al dominio transmembrana, producen apoptosis de las células endoteliales y suprimen uniones estrechas intercelulares en el endotelio, facilitando la actividad de las moléculas de adhesión leucocitarias que promueven el pasaje al subendotelio de los elementos del lumen, tales como monocitos, plaquetas, LDLOX, RLPs oxidables y lipoproteínas (a) (Lp(a)) semejantes al plasminógeno. Las LDLOX subendoteliales aumentan la movilidad de células musculares lisas. Los monocitos subendoteliales se establecen como residentes, e incorporan LDLOX, convirtiéndose sucesivamente en macrófagos, células espumosas y lesiones aterogénicas. Sin embargo, desde Assmann G y su estudio PROCAM no puede ignorarse el papel de los triglicéridos y colesterol de lipoproteínas de alta densidad (C-HDL) como componentes del cuadro de riesgo en ECV.


LOX-1 is an endothelial receptor belonging to the family of lectins. Its biological activity has a strong impact on inflammatory, oxidative and atherogenic phenomena in endothelium. When Low Density Lipoprotein receptor (RLDL) and its regulation were known, the atherogenic role of the cholesterol transported in LDL (LDL-C) was confirmed. This lipoprotein role in atherosclerosis was the base to use the term dyslipoproteinemia instead of dyslipidemia. In post-prandial conditions, triglyceride-rich lipoproteins like chylomicrons and very low-density lipoproteins (VLDL), are degraded by lipoprotein lipase (LPL) on the vascular wall, with the resultant formation of chylomicron remnants (CR) and intermediate density lipoproteins (IDL) respectively, which as a whole are called remnant lipoproteins (RLPs). Depending on oxidative stress, RLPs are oxidized and then they can bind the LOX-1. In this process, fatty acids are also released, injuring endothelial cells and contributing to open gaps in endothelium, which under physiological conditions, is a barrier of cells with tight junctions. The intracellular domain of LOX-1 regulates the recognition of oxidized LDL (oxLDL) and RLPs, and its effect depends on reactive oxygen species (ROS). LOX-1 transmembrane domain acts in the passage of oxLDL and monocytes to the sub-endothelium. Inhibition of LOX-1 by specific antibodies prevents its binding with OxLDL, restoring the barrier between the vascular lumen and sub-endothelium. By contrast, the oxLDL, attached to the transmembrane domain, produce apoptosis of endothelial cells and the suppression of narrow intercellular junctions in the endothelium. Thus, enabling the activity of leucocyte adhesion molecules that promote the transfer to subendothelial elements lumen of monocytes, platelets, oxLDL, oxidized RLPs and lipoprotein (a) (Lp (a)), similar to plasminogen such as. Sub-endothelial OxLDL increase the mobility of smooth muscle cells. Sub-endothelial monocytes establish as resident, up-take oxLDL and successively become into macrophages, foam cells and atherosclerotic lesions. However, since Assman’s PROCAM study, the role of triglycerides and High Density Lipoprotein-cholesterol (HDL-C), as components of cardiovascular risk, cannot be ignored.


LOX-1 é um receptor endotelial da família das lectinas. Sua atividade biológica tem um importante impacto nos fenômenos inflamatórios, oxidativos e aterogênicos endoteliais. Quando foi conhecido o receptor da lipoproteína de baixa densidade (RLDL) e sua regulação, afirmou-se o papel aterogênico do colesterol transportado nesta lipoproteína (C-LDL). Este papel das lipoproteínas foi a base da denominação de dislipoproteinemias em substituição de dislipidemias. Em condições pós-prandiais, as lipoproteínas ricas em triglicérides como quilomícrons e Lipoproteínas de muito baixa densidade (VLDL) são degradadas pela lipoproteína lipase (LPL) da parede vascular, produzindo remanescentes de quilomícrons (RQ) e lipoproteínas de densidade intermediária (IDL) respectivamente, que em conjunto são chamadas lipoproteínas remanescentes (RLPs). Dependendo do estresse oxidativo, as RLPs são oxidáveis e podem se ligar ao LOX-1. Também são liberados ácidos graxos que injuriam células endoteliais e contribuem na abertura de fendas no endotélio, que em condições fisiológicas é uma barreira de células com uniões estreitas. O domínio intracelular de LOX-1 regula o reconhecimento de lipoproteínas de baixa densidade oxidativa (LDLOX) e de RLPs. Também possui um efeito dependente dos radicais reativos de oxigênio (ROS). Seu domínio transmembrana atua na passagem de LDLOX e monócitos para o subendotélio. A inibição de LOX-1 com anticorpos específicos impede sua união com LDLOX restabelecendo a barreira entre o lúmem vascular e o subendotélio. Entretanto, as LDLOX ligadas ao domínio transmembrana produzem apoptose das células endoteliais e suprimem estreitas junções intercelulares no endotélio, facilitando a atividade das moléculas de adesão leucocitária que promovem a passagem para o subendotélio de elementos do lúmem, tais como monócitos, plaquetas, LDLOX, RLPs oxidáveis e lipoproteínas (a) [Lp(a)] semelhantes ao plasminogênio. As LDLOX subendoteliais aumentam a mobilidade das células musculares lisas. Os monócitos subendoteliais se estabelecem como residentes, e incorporam LDLOX, virando sucessivamente em macrófagos, células espumosas e lesões aterogênicas. No entanto, desde Assman G e seu estudo PROCAM, não pode se ignorar o papel dos triglicérides e do colesterol de lipoproteínas de alta densidade (C-HDL) como componentes do evento de risco em ECV.


Assuntos
Endotélio , Inflamação , Lectinas , Estresse Oxidativo , Lipoproteínas LDL , Receptores de LDL Oxidado
5.
Thyroid ; 26(3): 365-72, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26839156

RESUMO

BACKGROUND: Qualitative lipoprotein changes, such as an increase in fasting remnants, are reported in subclinical hypothyroidism (SCH). It was hypothesized that such changes are due to reduced hepatic lipase (HL) activity in SCH: HL is an enzyme regulated by thyroid hormones, and is involved in the degradation of triglyceride (TG)-rich remnants. This study aimed to quantify remnant-like lipoproteins (RLP), small dense LDL (sdLDL), and HL activity in women with SCH, and to assess these parameters after levothyroxine replacement therapy. METHODS: This was an observational cross-sectional study with a subsequent longitudinal follow-up. Findings in women with thyrotropin levels >4.5 mIU/L (SH group) were compared with age- and body mass index (BMI)-matched euthyroid women (control group). In addition, a subgroup analysis was undertaken in SCH women who chose to receive levothyroxine treatment (0.9 µg/kg/day) for 6 months. RLP was quantified by measuring cholesterol (RLP-C) and triglycerides (RLP-TG) after immunoaffinity chromatography, and sdLDL by automated standardized methods; HL activity was measured in post-heparin plasma. RESULTS: The SCH group included 37 women; 29 women were included in the control group. In addition, 22 women with SCH were included in the subgroup analysis (levothyroxine treatment). Significantly higher RLP values were observed in the SCH group than in the control group: RLP-C (median [range], mg/dL): 20.3 (5.8-66.8) versus 10.2 (2.7-36.3), p = 0.005; RLP-TG (mg/dL): 26.3 (3.2-123.3) versus 12.1 (2.5-61.6), p = 0.033. HL activity (mean ± standard deviation [SD], µmol free fatty acid/mL post-heparin plasma.h)-9.83 ± 4.25 versus 9.92 ± 5.20, p = 0.707-and sdLDL levels (mg/dL)-23.1 ± 10.7 versus 22.6 ± 8.4, p = 0.83-were similar. After levothyroxine, RLP-C decreased-21.5 (5.8-66.8) versus 17.2 (4.1-45.6), p = 0.023-and HL increased-9.75 ± 4.04 versus 11.86 ± 4.58, p = 0.012-in the subgroup of SCH women. No changes in sdLDL were observed. CONCLUSIONS: Women with SCH have higher RLP levels than matched controls do, but their RLP-C levels decrease significantly following levothyroxine therapy. Furthermore, HL activity also increases after levothyroxine therapy and can be interpreted as a possible explanation for the decrease in RLP-C.


Assuntos
Terapia de Reposição Hormonal , Hipotireoidismo/tratamento farmacológico , Lipase/metabolismo , Lipoproteínas LDL/sangue , Fígado/efeitos dos fármacos , Tiroxina/uso terapêutico , Adulto , Idoso , Doenças Assintomáticas , Biomarcadores/sangue , Estudos de Casos e Controles , Colesterol/sangue , Estudos Transversais , Feminino , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/diagnóstico , Hipotireoidismo/enzimologia , Lipoproteínas/sangue , Fígado/enzimologia , Estudos Longitudinais , Pessoa de Meia-Idade , Resultado do Tratamento , Triglicerídeos/sangue
6.
Materials (Basel) ; 8(4): 1951-1965, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28788041

RESUMO

A series of new organic polyimides were synthesized from 4-fluoro-4'4"-diaminotriphenylmethane and four different aromatic dianhydrides through a one-step, high-temperature, direct polycondensation in m-cresol at 180-200 °C, resulting in the formation of high-molecular-weight polyimides (inherent viscosities ~ 1.0-1.3 dL/g). All the resulting polyimides exhibited good thermal stability with initial decomposition temperatures above 434 °C, glass-transition temperatures between 285 and 316 °C, and good solubility in polar aprotic solvents. Wide-angle X-ray scattering data indicated that the polyimides were amorphous. Dense membranes were prepared by solution casting and solvent evaporation to evaluate their gas transport properties (permeability, diffusivity, and solubility coefficients) toward pure hydrogen, helium, oxygen, nitrogen, methane, and carbon dioxide gases. In general, the gas permeability was increased as both the fractional free volume and d-spacing were also increased. A good combination of permeability and selectivity was promoted efficiently by the bulky hexafluoroisopropylidene and 4-fluoro-phenyl groups introduced into the polyimides. The results indicate that the gas transport properties of these films depend on both the structure of the anhydride moiety, which controls the intrinsic intramolecular rigidity, and the 4-fluoro-phenyl pendant group, which disrupts the intermolecular packing.

7.
Eur J Clin Invest ; 44(10): 951-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25145771

RESUMO

BACKGROUND: Matrix metalloproteinases (MMPs), especially MMP-2 and MMP-9, have been identified in atherosclerotic plaques and have been directly associated with plaque remodelling and vulnerability. Cardiovascular disease (CVD) is related to insulin resistance (IR) and obesity, characterized by changes in plasma levels of inflammatory markers, such as adiponectin and C-reactive protein (CRP). Our aim was to evaluate the impact of both proteins on MMP-2 and MMP-9 behaviour in individuals with IR. MATERIALS AND METHODS: Plasma MMP-2 and MMP-9 activity, adiponectin and hs-CRP concentration and lipoprotein profile were determined in 52 patients with metabolic syndrome (MS) and 27 controls. RESULTS: Patients with MS presented significantly higher MMP-2 activity than controls: 0·95 ± 0·12 vs. 0·77 ± 0·15 relative units (RU) (P < 0·001), while MMP-9 activity was not detectable. MMP-2 activity decreased across quartiles of adiponectin, being significantly reduced in individuals with the highest levels of adiponectin in compared with the lowest levels (0·75 ± 0·17 vs. 0·93 ± 0·09 RU, P < 0·005). This difference persisted significant after adjusting by obesity markers. MMP-2 activity was significantly increased in individuals with the highest levels (G3) compared with those with the lowest levels (G1) of hs-CRP (0·94 ± 0·12 vs. 0·86 ± 0·12, P = 0·041) CONCLUSION: In this study, we observed that adiponectin levels predicted MMP-2 plasma activity independently of obesity. This finding suggests that the inflammatory process, associated with the highest CVD risk, would be involved in MMPs vascular production.


Assuntos
Adiponectina/fisiologia , Proteína C-Reativa/fisiologia , Metaloproteinase 2 da Matriz/metabolismo , Síndrome Metabólica/enzimologia , Obesidade/enzimologia , Adulto , Idoso , Biomarcadores/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Resistência à Insulina/fisiologia , Metabolismo dos Lipídeos/fisiologia , Lipoproteínas/metabolismo , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Materials (Basel) ; 7(8): 5711-5734, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-28788156

RESUMO

Compounds of poly(ionic liquid)s (PILs), derived from imidazole with different alkylic chain lengths located in the third position of the imidazolium ring (poly(1-vinyl-3-dodecyl-imidazolium) (PImC12), poly(1-vinyl-3-octylimidazolium) (PImC8) and poly(1-vinyl-3-butylimidazolium) (PImC4) hexafluorophosphate) were synthesized. These compounds were tested as corrosion inhibitors on aluminum alloy AA6061 in diluted sulfuric acid (0.1-1 M H2SO4) by weight loss tests, polarization resistance measurements and inductively coupled plasma optical emission spectroscopy. Langmuir's isotherms suggested film formation on bare alloy while standard free energy indicated inhibition by a physisorption process. However, compound efficiencies as inhibitors ranked low (PImC12 > PImC8 > PImC4) to reach 61% for PImC12 in highly diluted acidic solution. Apparently, the high mobility of sulfates favored their adsorption in comparison to PILs. The surface film displayed general corrosion, and pitting occurred as a consequence of PILs' partial inhibition along with a continuous dissolution of defective patchy film on formation. A slight improvement in efficiency was displayed by compounds having high molecular weight and a long alkyl chain, as a consequence of steric hindrance and PIL interactions.

9.
Rev. chil. ter. ocup ; 13(1): 23-32, ago. 2013. tab, ilus
Artigo em Espanhol | LILACS | ID: lil-705110

RESUMO

Propósito: el objetivo de este trabajo fue indagar en características de la forma, función y significado de la conducción de automóviles en un grupo de adultos mayores residentes en la ciudad de Santiago de Chile, en el año 2011, a partir de sus experiencias y percepciones. Metodología: Bajo un paradigma naturalista interpretativo se realizó una entrevista en profundidad a siete participantes; luego la información fue analizada con un enfoque de teoría fundamentada por medio de comparación constante, y generando categorías con hallazgos/temas principales. Resultados: en el grupo estudiado, la conducción presentaba una forma condicionada por factores atribuibles al envejecimiento tales como declive visual, perceptual y cognitivo, y por el contexto físico y social. La función de la conducción emergió como medio facilitador de actividades instrumentales de la vida diaria y tiempo libre; y el significado de la conducción emergió como prioritario debido a su vinculación con la autonomía, la independencia y la continuidad biográfica al permitir la mantención de roles que eran importantes para los participantes. Conclusiones: este trabajo posiciona la conducción de automóviles como una ocupación cuya forma, función y significado, contribuirían de manera importante al bienestar de los adultos mayores y releva información a considerar en los contextos de atención de terapia ocupacional para adultos mayores.


Purpose: the aim of this research was to inquire on characteristics of form, function and meaning of car driving in a group of community dwelling older adults in the city of Santiago de Chile, in 2011, from their perspectives and experiences. Methods: qualitative in-depth interviews were carried out to seven participants; then information was analyzed using a grounded theory approach using constant comparison, and generating categories with main findings / themes. Results: within the study group, car driving had a form conditioned by factors associable to aging such as visual, perceptual and cognitive declining, and by the social and physical context. Function of car driving emerged mainly as a facilitator of instrumental activities of daily living and leisure; and the meaning of the activity was probably the most important component, since car driving was perceived by the group as a priority and fundamental activity as it enabled independence, autonomy and biographical continuity by maintenance of significant roles. Conclusions: this study positions car driving as an occupation whose form, function and meaning, would contribute significantly to wellbeing and quality of life of older adults. Clinical implications for occupational therapy practice are also discussed.


Assuntos
Feminino , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Envelhecimento , Condução de Veículo , Chile , Entrevistas como Assunto , Terapia Ocupacional , Autonomia Pessoal , Qualidade de Vida
10.
Microvasc Res ; 89: 153-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23778199

RESUMO

OBJECTIVE: It has been reported that LDL inhibits endothelium-dependent relaxation (EDR) and that HDL can neutralize this effect. However, the atherogenic properties of VLDL have been so far difficult to demonstrate. Studies on VLDL are controversial, and nothing is known about the role of HDL on potential VLDL vascular actions. We examined the effect of human VLDLs on EDR, and the role of HDL in this system. METHODS: VLDL (n=14) and LDL (n=6) were isolated from volunteer subjects. Normal HDL was obtained from one healthy donor. VLDL ability to inhibit ACh-induced vasorelaxation (10(-9)-10(-5)mM) on aortic rings previously precontracted by noradrenaline (10(-8)mM) was measured in the presence and absence of HDL. RESULTS: ACh-induced maximal relaxation (R%) was mildly, but not significantly attenuated in the presence of VLDL (72±7%), while LDL caused a significant inhibition (60±10%, p<0.05) when compared to incubation in the absence of lipoproteins. VLDLs were subdivided into 2 groups depending on their cholesterol/triglyceride ratio: 0.18-0.22 (n=8) was considered typical and 0.10-0.15, rich in triglycerides (VLDLRT, n=6). Typical VLDL had no effect on EDR (p=0.38), however R% from VLDLRT was lower (54±7%, p<0.01) similar to the one obtained with LDL (p=0.32). HDL showed favorable effects on EDR inhibition induced by the presence of VLDLRT (p<0.05.). CONCLUSION: Although typical VLDL did not cause endothelial dysfunction, triglyceride-enriched VLDL had inhibitory effect on EDR. It is proposed that alterations in VLDL composition would increase its atherogenic capacity. Moreover HDL appears to protect endothelium from VLDL action.


Assuntos
HDL-Colesterol/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Lipoproteínas VLDL/metabolismo , Triglicerídeos/metabolismo , Acetilcolina/química , Animais , Aorta/patologia , Aterosclerose/patologia , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Lipoproteínas/química , Masculino , Norepinefrina/química , Ratos , Ratos Sprague-Dawley , Vasodilatação/efeitos dos fármacos
11.
Acta bioquím. clín. latinoam ; Acta bioquím. clín. latinoam;47(1): 95-100, mar. 2013.
Artigo em Espanhol | LILACS | ID: lil-727419

RESUMO

La disminución de colesterol-LDL (c-LDL) se considera meta principal del tratamiento de pacientes con riesgo cardiovascular. Sin embargo, pacientes con Enfermedad Renal Crónica (ERC) en hemodiálisis presentan c-LDL menor de 100 mg/dL, aumentos moderados de triglicéridos y baja frecuencia de colesterol-HDL por debajo de valores deseables. Esta condición se encuadra dentro del fenómeno conocido como "epidemiología inversa", en la cual la conocida asociación prevalente entre hipercolesterolemia, hipertensión arterial, obesidad y morbimortalidad por eventos cardiovasculares no se encuentra y, por el contrario se invierte la estrecha relación de estos parámetros con eventos cardiovasculares propia de los pacientes no hemodializados. Por un lado el 35% de los pacientes con ERC presentan diabetes mellitus tipo 2 y por otra parte, existen otros factores patogénicos menos conocidos como la Lipoproteína asociada a Fosfolipasa A2, la Proteína C Reactiva, los remanentes lipoproteicos, la Lp(a) y enzimas y proteínas asociadas a la HDL, como la Paraoxonasa y Apo A-I. El conjunto de factores descritos podrían reemplazar, en pacientes con ERC en hemodiálisis, al colesterol-LDL (c-LDL), típico analito que en otros pacientes actúa como factor de riesgo y/o patogénico de aterosclerosis y no sólo como marcador circulante. Una explicación plausible respecto al c-LDL disminuído es la modificación cualitativa de LDL por oxidación, glicación, carbamilación, la presencia de LDL pequeñas y densas, fenómenos inflamatorios y malnutrición.


Assuntos
Humanos , Nefropatias , Epidemiologia , Diálise Renal , LDL-Colesterol , Lisofosfolipase
12.
Acta bioquím. clín. latinoam ; Acta bioquím. clín. latinoam;47(1): 95-100, mar. 2013.
Artigo em Espanhol | BINACIS | ID: bin-130988

RESUMO

La disminución de colesterol-LDL (c-LDL) se considera meta principal del tratamiento de pacientes con riesgo cardiovascular. Sin embargo, pacientes con Enfermedad Renal Crónica (ERC) en hemodiálisis presentan c-LDL menor de 100 mg/dL, aumentos moderados de triglicéridos y baja frecuencia de colesterol-HDL por debajo de valores deseables. Esta condición se encuadra dentro del fenómeno conocido como "epidemiología inversa", en la cual la conocida asociación prevalente entre hipercolesterolemia, hipertensión arterial, obesidad y morbimortalidad por eventos cardiovasculares no se encuentra y, por el contrario se invierte la estrecha relación de estos parámetros con eventos cardiovasculares propia de los pacientes no hemodializados. Por un lado el 35% de los pacientes con ERC presentan diabetes mellitus tipo 2 y por otra parte, existen otros factores patogénicos menos conocidos como la Lipoproteína asociada a Fosfolipasa A2, la Proteína C Reactiva, los remanentes lipoproteicos, la Lp(a) y enzimas y proteínas asociadas a la HDL, como la Paraoxonasa y Apo A-I. El conjunto de factores descritos podrían reemplazar, en pacientes con ERC en hemodiálisis, al colesterol-LDL (c-LDL), típico analito que en otros pacientes actúa como factor de riesgo y/o patogénico de aterosclerosis y no sólo como marcador circulante. Una explicación plausible respecto al c-LDL disminuído es la modificación cualitativa de LDL por oxidación, glicación, carbamilación, la presencia de LDL pequeñas y densas, fenómenos inflamatorios y malnutrición.(AU)


The decrease in LDL cholesterol (LDL-C) is considered the main goal in the treatment of patients with atherosclerotic cardiovascular risk. However, patients with chronic kidney disease (CKD) on hemodialysis have LDL-C below 100 mg/dL, moderate increases in triglycerides and low frequency of HDL cholesterol values below desirable.This condition fits into the phenomenon known as "reverse epidemiology", in which the normal relationship between hypercholesterolemia, high blood pressure, obesity and cardiovascular morbidity and mortality is not found; contrarily, there is a reversal in the close relationship of these parameters with cardiovascular events typical of non-hemodialyzed patients. On the one hand, 35% of CKD patients have Type 2 diabetes mellitus and on the other hand, there are other lesser known pathogenic factors such as lipoprotein-associated phospholipase A2, C-reactive protein, remnant lipoproteins, Lp(a) and enzymes and proteins associated to HDL such as paraoxonase and Apo A-I. The set of factors described could replace, in CKD patients on hemodialysis, LDL cholesterol, a typical analyte that, in other patients, acts as a risk and/or pathogenesis factor of atherosclerosis and not only as a circulating marker. A likely explanation for decreased C-LDL cholesterol is qualitative modification of LDL as a result of oxidation, glycation, carbamylation, occurrence of small and dense LDL, inflammatory phenomena and malnutrition.(AU)


A diminuiþÒo de colesterol-LDL (c-LDL) considera-se objetivo principal do tratamento de pacientes com risco cardiovascular. Entretanto, pacientes com Doenþa Renal Cr¶nica (ERC) em hemodiálise apresentam c-LDL menor de 100 mg/dL, aumentos moderados de triglicerídeos e baixa frequÛncia de colesterol-HDL inferior aos valores desejáveis. Esta condiþÒo se enquadra dentro do fen¶meno conhecido como "epidemiologia reversa", na qual a conhecida associaþÒo prevalente entre hipercolesterolemia, hipertensÒo arterial, obesidade e morbimortalidade por eventos cardiovasculares nÒo se encontra e, pelo contrário se inverte a estreita relaþÒo destes parÔmetros com eventos cardiovasculares própria dos pacientes nÒo hemodialisados. De um lado, 35% dos pacientes com ERC apresentam Diabetes Melito tipo 2 e do outro, existem diferentes fatores patogÛnicos menos conhecidos como a Lipoproteína associada a Fosfolipase A2, a Proteína C Reativa, os remanescentes lipoproteicos, a Lp(a) e enzimas e proteínas associadas O HDL, como a Paraoxonase e Apo A-I. O conjunto de fatores descritos poderia substituir, em pacientes com ERC em hemodiálise, o colesterol-LDL (c-LDL), típico analito que em outros pacientes age como fator de risco e/ou patogÛnico de aterosclerose e nÒo só como marcador circulante. Uma explicaþÒo plausível a respeito do c-LDL diminuído é a modificaþÒo qualitativa de LDL por oxidaþÒo, glicaþÒo, carbamilaþÒo, a presenþa de LDL pequenas e densas, fen¶menos inflamatórios e malnutriþÒo.(AU)

13.
Acta bioquím. clín. latinoam ; Acta bioquím. clín. latinoam;47(1): 95-100, mar.2013.
Artigo em Espanhol | BINACIS | ID: bin-129806

RESUMO

La disminución de colesterol-LDL (c-LDL) se considera meta principal del tratamiento de pacientes con riesgo cardiovascular. Sin embargo, pacientes con Enfermedad Renal Crónica (ERC) en hemodiálisis presentan c-LDL menor de 100 mg/dL, aumentos moderados de triglicéridos y baja frecuencia de colesterol-HDL por debajo de valores deseables. Esta condición se encuadra dentro del fenómeno conocido como "epidemiología inversa", en la cual la conocida asociación prevalente entre hipercolesterolemia, hipertensión arterial, obesidad y morbimortalidad por eventos cardiovasculares no se encuentra y, por el contrario se invierte la estrecha relación de estos parámetros con eventos cardiovasculares propia de los pacientes no hemodializados. Por un lado el 35% de los pacientes con ERC presentan diabetes mellitus tipo 2 y por otra parte, existen otros factores patogénicos menos conocidos como la Lipoproteína asociada a Fosfolipasa A2, la Proteína C Reactiva, los remanentes lipoproteicos, la Lp(a) y enzimas y proteínas asociadas a la HDL, como la Paraoxonasa y Apo A-I. El conjunto de factores descritos podrían reemplazar, en pacientes con ERC en hemodiálisis, al colesterol-LDL (c-LDL), típico analito que en otros pacientes actúa como factor de riesgo y/o patogénico de aterosclerosis y no sólo como marcador circulante. Una explicación plausible respecto al c-LDL disminuído es la modificación cualitativa de LDL por oxidación, glicación, carbamilación, la presencia de LDL pequeñas y densas, fenómenos inflamatorios y malnutrición.(AU)


Assuntos
Humanos , Epidemiologia , Nefropatias , Diálise Renal , LDL-Colesterol , Lisofosfolipase
14.
Eur J Nutr ; 52(1): 297-305, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22457075

RESUMO

INTRODUCTION: Obese ß rats may be a suitable model to evaluate the association between calcium intake (CaI) and obesity during growth. OBJECTIVE: The present study comparatively evaluated Ca absorption and retention, and changes in body composition in spontaneously genetically obese (ß) male rats fed three different dietary Ca levels: high 0.9% (HCa); normal: 0.5% (NCa); low: 0.2% (LCa). METHODS: Pregnant rats were fed isocaloric diets which varied in Ca content only. Male pups continued feeding the same maternal diet until postnatal day 60. The percentage of Apparent Ca absorption (CaA %), Ca balance (CaB), body composition, glucose, triglycerides (TGL), and insulin levels were evaluated. RESULTS: Food consumption and body weight (BW) were higher in Group LCa than in Groups NCa and HCa (p < 0.01); no differences were observed between the latter two groups. Group LCa presented the highest body fat, liver weight, perigonadal and retroperitoneal fat (p < 0.05); conversely, body ashes and total skeleton bone mineral content were significantly lower compared with animals in both the NCa (p < 0.01) and HCa groups (p < 0.01). CaB (mg/day) reached a plateau at the highest CaI (mg/day) value (r = 0.985, p < 0.001). CaA%, serum glucose, insulin, and TGL levels rose as CaI decreased (p < 0.01). CONCLUSIONS: Although further studies are required, low Ca consumption in this strain of rats could modulate BW inducing changes in several lipid metabolism parameters, which in turn lead to an increase in body fat.


Assuntos
Composição Corporal , Cálcio da Dieta/farmacocinética , Cálcio/metabolismo , Obesidade/genética , Adiposidade , Animais , Peso Corporal , Dieta , Feminino , Lactação , Metabolismo dos Lipídeos , Masculino , Gravidez , Taxa de Gravidez , Ratos , Triglicerídeos/sangue
15.
Clin Biochem ; 45(4-5): 293-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22245548

RESUMO

OBJECTIVE: To study size heterogeneity of triglyceride rich lipoproteins (TRL) in metabolic syndrome (MS). DESIGN AND METHODS: Thirty MS patients and 14 healthy subjects were included. In fasting serum we measured: lipid profile, free fatty acids (FFA) and adiponectin; TRL were isolated (d<1.006 g/mL) and analysis by size exclusion HPLC followed by UV detection was performed; each subfraction was expressed as percentage of total TRL. RESULTS: MS patients, even those with normal triglycerides, presented higher proportion of very large VLDL (90 nm diameter) and large VLDL (60 nm) and slightly lower of typical VLDL (37 nm) (p<0.04); increased FFA (p=0.04) and lower adiponectin (p=0.001). FFA correlated with large VLDL% (r=0.58; p=0.003), independently of insulin-resistance and waist. Furthermore, the lower the adiponectin, the greater the predominance of large VLDL (r=-0.40; p=0.04). CONCLUSION: MS was associated with large VLDL, described as more atherogenic beyond triglyceride levels. Size exclusion HPLC would represent a useful tool for assessing subfractions' lipoprotein profile.


Assuntos
Lipoproteínas VLDL/sangue , Síndrome Metabólica/sangue , Adiponectina/sangue , Adulto , Argentina/epidemiologia , Aterosclerose/epidemiologia , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Ácidos Graxos não Esterificados/sangue , Feminino , Humanos , Lipoproteínas VLDL/química , Lipoproteínas VLDL/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Risco , Triglicerídeos/sangue , Ultracentrifugação
16.
Clin Chim Acta ; 412(1-2): 143-7, 2011 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-20887718

RESUMO

BACKGROUND: It is not elucidated if liver fat deposits associated to metabolic syndrome (MS) aggravate the atherogenic state. We evaluated, in MS patients, if the presence of non-alcoholic hepatic steatosis (HS) determines differences in inflammatory markers and VLDL characteristics. METHODS: Seventy-five patients with MS were divided into 2 groups depending on the presence or absence of HS, assessed by ultrasound. Lipid profile, free fatty acids (FFA), VLDL composition, adiponectin, tumor necrosis factor-alpha (TNF-α), high sensitivity C-reactive protein (hs-CRP), and soluble adhesion molecules (sVCAM-1 and sICAM-1) were measured. RESULTS: HS patients presented increased triglycerides levels, HOMA-IR and FFA. Patients with HS showed a reduction in adiponectin (p = 0.04) and increase in hs-CRP (p = 0.02), independently of insulin-resistance (IR). FFA correlated positively with TNF-α (p = 0.04) and inversely with adiponectin (p = 0.01). hs-CRP correlated with all inflammatory markers, independently of IR: TNF-α (r = 0.34, p = 0.02), sVCAM-1 (r = 0.29 p = 0.03), sICAM-1 (r = 0.56, p = 0.01), adiponectin (r = -0.34, p = 0.04). HS patients presented higher VLDL mass and number of particles. Adiponectin correlated with VLDL cholesterol content (r = -0.47, p = 0.04), independently of IR. VLDL, once secreted, would suffer from changes, becoming more atherogenic. CONCLUSIONS: Simple HS would play an important role increasing cardiovascular risk, independently of IR. hs-CRP may represent a useful biomarker of this condition.


Assuntos
Aterosclerose/sangue , Aterosclerose/complicações , Síndrome Metabólica/sangue , Síndrome Metabólica/complicações , Adiponectina/sangue , Adulto , Biomarcadores/sangue , Fígado Gorduroso/sangue , Fígado Gorduroso/complicações , Feminino , Humanos , Inflamação/sangue , Lipoproteínas VLDL/sangue , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica
17.
Clin Chim Acta ; 412(7-8): 587-92, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21159313

RESUMO

BACKGROUND: Hepatic steatosis (HS) is closely associated to metabolic syndrome (MS). Both, VLDL-triglyceride oversecretion and intrahepatic deposits, can take place. We evaluated VLDL characteristics, CETP, hepatic lipase (HL), IDL and small dense LDL (sdLDL), in patients with HS associated to MS. METHODS: We studied 3 groups matched by age and sex: 25 MS patients with HS (diagnosed by ultrasonography), 25 MS patients without HS and 25 healthy controls. Main measurements were: lipid profile, free fatty acids, VLDL composition, VLDL size by HPLC, CETP and HL activities, IDL-cholesterol and sdLDL-cholesterol. RESULTS: Patients with HS presented higher triglyceride levels, HOMA-IR and free fatty acids, VLDL mass and VLDL-apoB (p<0.05). No differences in VLDL composition were observed. MS groups presented higher proportion of large VLDL than controls (p<0.05). HS group showed higher CETP than controls (p=0.01) and almost higher than MS without HS (p=0.06). CETP correlated with VLDL-cholesterol content, r=0.48, p<0.005. The increase in sdLDL-cholesterol correlated with CETP (r=0.47) and HL (r=0.56), independent of insulin resistance (p<0.003). CONCLUSION: Despite intrahepatic fat, patients with HS secreted higher number of VLDL particles. CETP would have a remodeling action on VLDL in circulation, enriching it in cholesterol and also favoring, together with HL, the formation of sdLDL.


Assuntos
Fígado Gorduroso/sangue , Lipoproteínas LDL/sangue , Lipoproteínas VLDL/sangue , Síndrome Metabólica/sangue , Adulto , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Mol Divers ; 14(4): 777-87, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20091120

RESUMO

Seventy five ionic liquids (ILs) were tested as a sequestering agent of sulfured compounds in natural gasoline (NG). Desulphurization of NG was performed by means of liquid-liquid extraction method at room temperature and atmospheric pressure. Experimental ILs containing imidazolium, pyridinium, and ammonium cations along with organic and inorganic anions were synthesized conventionally and under microwave and sonochemical conditions. The effect of the molecular structure of ILs on the desulfurization efficiency of NG with high sulfur content was evaluated. Analysis indicated that the anion type played a more important role than the cation on the desulphurization process. ILs based on halogen-ferrates and halogen-aluminates exhibited the highest efficiency in sulfur removal, and their efficiency is further improved when there is an excess of metallic salt in a ratio of at least 1:1.3 during the synthesis of the corresponding IL. An explanation for the ability of metallic ILs to remove sulfur-containing compounds from natural gasoline based on the ratio of the ionic charge to the atomic radius is proposed. Furthermore, a method to recover and reuse water-sensitive to halogenated precursors is described.


Assuntos
Fracionamento Químico/métodos , Gasolina , Líquidos Iônicos/química , Líquidos Iônicos/farmacologia , Compostos de Enxofre/química , Enxofre/isolamento & purificação , Cromatografia Líquida/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Eficiência , Gasolina/análise , Ligação de Hidrogênio , Modelos Biológicos , Enxofre/química , Enxofre/metabolismo , Compostos de Enxofre/análise , Compostos de Enxofre/farmacocinética
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