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1.
Water Sci Technol ; 73(8): 2007-16, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27120655

RESUMO

The sorption processes of red 5 (R5) and yellow 5 (Y5) dyes by iron modified and sodium bentonite in aqueous solutions was evaluated. The modified clay was prepared, conditioned and characterized. The sodium clay did not remove any of either dye. The sorption kinetics and isotherms of R5 and Y5 dyes by iron modified clay were determined. The maximum removal percentages achieved were 97% and 98% for R5 and Y5, respectively, and a contact time of 72 h; the experimental data were best adjusted to Ho model. The isotherms of both dyes were best adjusted to the Langmuir model and the maximum adsorption capacities of the modified clay were 11.26 mg/g and 5.28 mg/g for R5 and Y5, respectively. These results indicate that adsorption processes have a high probability to be described as chemisorption on a homogeneous material. Temperature range between 283 and 213 K does not affect the adsorption of Y5 by the iron modified clay, but the adsorption process of R5 was affected, and the thermodynamic parameters could be calculated, which indicate a chemisorption mechanism.


Assuntos
Silicatos de Alumínio/química , Corantes/química , Ferro/química , Poluentes Químicos da Água/química , Adsorção , Bentonita , Argila , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica
2.
Arterioscler Thromb Vasc Biol ; 27(9): 1991-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17600225

RESUMO

OBJECTIVES: The purpose of this study was to establish whether oxidized low-density lipoprotein (oxLDL) contributes to cytokine overproduction via upregulation of CD14 and toll-like receptor-4 (TLR-4) expression on circulating monocytes of unstable angina (UA) patients. METHODS AND RESULTS: Expression of CD14 and TLR-4 on circulating monocytes, and the concentration of plasma oxLDL, (interleukin [IL])-6, IL-1 beta, IL-8, tumor necrosis factor (TNF)-alpha, monocyte chemoattractant protein-1 (MCP-1) were measured in 27 control (C) subjects, 29 patients with stable angina (SA), and 27 with UA. CD14 and TLR-4 expression on monocytes and circulating IL-6, IL-1 beta, and oxLDL were higher in UA than in SA and C subjects (P<0.001). In in vitro experiments, oxLDL increased CD14 and TLR-4 expression (P<0.001) in control monocytes as well as IL-6, IL-1 beta, and at a lower extent TNF-alpha and MCP-1 levels in the supernatant (P from <0.05 to <0.001). The preincubation of sera derived from UA patients but with control monocytes also induced a significant increase of CD14 and TLR-4 expression (P<0.001) and of IL-6 and IL-1 beta production (P<0.001) in the supernatant. CONCLUSIONS: In UA patients oxLDL may contribute to monocyte overproduction of some cytokines by upregulating CD14 and TLR-4 expression.


Assuntos
Angina Instável/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Lipoproteínas LDL/fisiologia , Monócitos/metabolismo , Receptor 4 Toll-Like/metabolismo , Idoso , Angina Instável/sangue , Feminino , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Regulação para Cima
3.
Am J Gastroenterol ; 95(6): 1491-4, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10894585

RESUMO

OBJECTIVE: Reduced bone mineral density (BMD) has been reported in ulcerative colitis (UC) patients, but body composition (fat and lean mass) has never been concomitantly studied. We sought to investigate BMD and body composition in a group of UC outpatients with the following characteristics: age 18-60 yr (men) and 18-45 yr (women); no intestinal resection; no immunosuppressive treatment; and regular menstruation. METHODS: Whole body and subregional BMD and body composition in 43 UC patients (21 men, 22 women; male mean age, 36.5 [21-57] yr; female mean age, 35.3 [23-45] yr) and 121 healthy volunteers were studied by means of dual X-ray photon absorptiometry. RESULTS: There were no differences in total and subregional BMD, or fat and lean mass between the patients and controls, except that the total and trunk lean mass of the UC women was lower than that in the normal controls. No correlation was found between lifetime steroid intake and BMD. CONCLUSIONS: UC outpatients do not differ from normal subjects in terms of BMD and fat mass. Mild and moderate UC does not represent a risk factor for osteopenia.


Assuntos
Composição Corporal , Densidade Óssea , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Absorciometria de Fóton , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Caracteres Sexuais
4.
J Hepatol ; 29(5): 701-6, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9833906

RESUMO

BACKGROUND/AIMS: Hepatitis C virus (HCV) easily undergoes genomic changes, thus accounting for the presence of different genotypes, with different geographic distributions and different outcomes of chronic hepatitis. Type 1b is frequently found in advanced diseases; however, since this genotype is the most prevalent in older patients, the association with advanced age and severity of the disease is confounding. The aim of this study was to assess changes in the prevalence of HCV genotypes by surveying a large population of chronic hepatitis C patients in Northern Italy, and to assess if the high prevalence of genotype 1b in older patients with advanced diseases simply reflects the duration of HCV infection, rather than intrinsic biological properties of HCV. METHODS: We studied 1368 HCV-RNA positive patients, with histologically proven chronic hepatitis. Drug addiction, blood transfusions and sporadically acquired infections represented the risk factors. RESULTS: Genotype 1b, the most prevalent isolate, and genotype 2a were associated with older age, cirrhosis, sporadically-acquired infections and blood transfusion, while types 1a, 3a, and 4 were associated with younger age, chronic persistent hepatitis and drug addiction. Patients with a history of transfusions were divided into four groups depending on the period of transfusion. The prevalence of genotype 1b decreased with time. Type 3a appeared only after 1979. CONCLUSION: The severity of chronic hepatitis C could be related more to the duration of the infection rather than to the intrinsic pathogenicity of HCV genotypes.


Assuntos
Genoma Viral , Hepacivirus/genética , Hepatite C Crônica/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Variação Genética , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/fisiopatologia , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade
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