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1.
Int Arch Allergy Immunol ; 152(3): 255-63, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20150743

RESUMO

The role of genetic and environmental factors, as well as their interaction, in the natural history of asthma, allergic rhinitis and chronic obstructive pulmonary disease (COPD) is largely unknown. This is mainly due to the lack of large-scale analytical epidemiological/genetic studies aimed at investigating these 3 respiratory conditions simultaneously. The GEIRD project is a collaborative initiative designed to collect information on biomarkers of inflammation and oxidative stress, individual and ecological exposures, diet, early-life factors, smoking habits, genetic traits and medication use in large and accurately defined series of asthma, allergic rhinitis and COPD phenotypes. It is a population-based multicase-control design, where cases and controls are identified through a 2-stage screening process (postal questionnaire and clinical examination) in pre-existing cohorts or new samples of subjects. It is aimed at elucidating the role that modifiable and genetic factors play in the occurrence, persistence, severity and control of inflammatory airway diseases, by way of the establishment of a historical multicentre standardized databank of phenotypes, contributed by and openly available to international epidemiologists. Researchers conducting population-based surveys with standardized methods may contribute to the public-domain case-control database, and use the resulting increased power to answer their own scientific questions.


Assuntos
Meio Ambiente , Projetos de Pesquisa Epidemiológica , Doenças Respiratórias/epidemiologia , Doenças Respiratórias/genética , Asma/epidemiologia , Asma/genética , Viés , Estudos de Casos e Controles , Coleta de Dados , Interpretação Estatística de Dados , Bases de Dados Factuais , Poluição Ambiental , Feminino , Habitação , Humanos , Itália/epidemiologia , Estudos Longitudinais , Masculino , Inquéritos Nutricionais , Fenótipo , Setor Público , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/genética , Rinite Alérgica Perene/epidemiologia , Rinite Alérgica Perene/genética , Rinite Alérgica Sazonal/epidemiologia , Rinite Alérgica Sazonal/genética , Inquéritos e Questionários
2.
J Endocrinol Invest ; 33(4): 244-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19915386

RESUMO

BACKGROUND: Zoledronic acid (Zol) is used successfully to inhibit bone resorption in tumor bone disease of various human cancer. Zol inhibits the mevalonate pathway and other potential targets include the inhibition of tyrosine phosphatase activity, disruption of metalloproteinase, secretion and down-regulation of the catalytic subunit of telomerase (hTERT). The six-transmembrane epithelial antigen of prostate protein (STEAP) is a new marker highly expressed at all phases of prostate cancer. AIM: Here, we analyzed for the first time the effect of Zol on STEAP gene expression in prostate cancer cells. MATERIAL AND METHODS: We evaluated the effects of Zol in STEAP gene expression by RT real time PCR in androgen-sensitive (LNCaP) and androgen-non-sensitive (PC3 and DU145) cell lines. To confirm the pro-apoptotic effect of Zol, we also analyzed the caspase-3 gene expression, that resulted up-regulated in cancer cell apoptosis. RESULTS: Zol strongly decreased cell viability and lowered STEAP gene expression in a dose-dependent manner. In addition, this effect was accompanied by an increase of apoptotic index and an up-regulation of caspase-3 gene expression. CONCLUSION: Zol may affect cancer cells also by targeting the gene expression of STEAP.


Assuntos
Antígenos de Neoplasias/metabolismo , Conservadores da Densidade Óssea/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Difosfonatos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Imidazóis/farmacologia , Oxirredutases/metabolismo , Neoplasias da Próstata/fisiopatologia , RNA Mensageiro/metabolismo , Antígenos de Neoplasias/genética , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Relação Dose-Resposta a Droga , Humanos , Masculino , Oxirredutases/genética , RNA Mensageiro/genética , Ácido Zoledrônico
3.
Reumatismo ; 61(1): 54-64, 2009.
Artigo em Italiano | MEDLINE | ID: mdl-19370189

RESUMO

Bisphosphonates are the most commonly prescribed medications for the treatment of osteoporosis. Despite evidence supporting the anti-fracture efficacy of aminobisphosphonates approximately 50% of patients do not follow their prescribed treatment regimen and/or discontinue treatment within the first year. Poor compliance is associated with negative outcomes, including increased fracture risk. Tolerability and safety are among the causes of poor compliance. Intravenous bisphosphonates avoids the gastrointestial intolerance and the complex dosing instruction of the oral route ensuring full compliance which may provide improved efficacy. However, there are some concerns regarding potent intravenous bisphosphonates as zoledronic acid with respect to tolerability, mainly the acute phase response and to safety, mainly a theoretical risk of over suppression of bone turnover, renal toxicity and osteonecrosis of the jaw. In the HORIZON study, 152 patients on active treatment (82) or placebo (70) underwent to a bone biopsy after double tetracycline labeling. Bone biopsies (iliac crest) were obtained at the final visit at month 36, 1 year after the last infusion. The biopsies were analyzed by histomorphometry on bone sections and by micro-CT (microCT) analysis. One hundred forthy-three biopsies (76 zoledronic acid, 67 placebo) had at least one microCT parameter measured and 111 were available for quantitative histomorphometry (59 zoledronic acid, 52 placebo). Micro-CT analysis of bone structure revealed higher trabecular bone volume (BV/TV), decreased trabecular separation (Tb.Sp), and a strong trend towards improvement in connectivity density in biopsies obtained from patients treated with zoledronic acid, indicating preservation of trabecular bone structure with respect to placebo. Histomorphometric analysis obtained from patients treated with zoledronic acid exhibited reduction of bone turnover, as suggested by decreased activation frequency (Ac.F) by 63%, mineralizing surface (MS/BS), bone formation rate (BFR/BV). In addition, mineral appositional rate (MAR), reflecting the bone-forming capacity of osteoblastic teams at the bone multicellular unit (BMU) level, was significantly higher in patients on active treatment. No sign of excessive suppression of bone turnover or mineralization impairment was detected, confirming the safety of the treatment with intravenous zoledronic acid once a year. These interesting findings are discussed in the article, particularly in terms of new histomorphometric results and clinical findings supporting the tolerability and safety of zoledronic acid.


Assuntos
Difosfonatos/uso terapêutico , Imidazóis/uso terapêutico , Osteoporose Pós-Menopausa/tratamento farmacológico , Fibrilação Atrial/induzido quimicamente , Biópsia , Densidade Óssea , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Difosfonatos/administração & dosagem , Difosfonatos/efeitos adversos , Feminino , Fraturas do Fêmur/etiologia , Fraturas do Fêmur/prevenção & controle , Seguimentos , Humanos , Imidazóis/administração & dosagem , Imidazóis/efeitos adversos , Infusões Intravenosas , Estudos Multicêntricos como Assunto , Osteoporose Pós-Menopausa/complicações , Ensaios Clínicos Controlados Aleatórios como Assunto , Insuficiência Renal/induzido quimicamente , Estudos Retrospectivos , Fatores de Risco , Segurança , Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/prevenção & controle , Fatores de Tempo , Ácido Zoledrônico
4.
J Endocrinol Invest ; 31(6): 525-30, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18591885

RESUMO

Primary hyperparathyroidism (PHPT) is a common endocrine disease. High levels of PTH cause demineralization of bone and increased risk of fracture. On the other hand, the effect of PHPT on bone structure is more ambiguous. The aim of this study was to evaluate the effect of PHPT on cancellous bone volume, structure, and microarchitecture. Thirteen transiliac biopsy specimens taken in untreated post-menopausal women aged 65+/-5 yr with primary hyperparathyroidism were compared with 13 biopsies taken in normal women aged 66+/-6 yr. None of the patients presented any other disorder affecting bone metabolism. In these samples we evaluated the direct and indirect histomorphometric parameters of bone microarchitecture using an image analysis system consisting of an epifluorescent microscope (Leica DMR) connected to an analogic 3 CCD camera (Sony DXC 390P) and a computer equipped with specific software for histomorphometric analyses. No significant differences between PHPT patients and controls in cancellous bone volume, trabecular thickness, and number were found. Two-dimensional parameters showed a preserved microarchitecture in PHPT patients. On the other hand, indirect parameters of microarchitecture [Marrow Star Volume (MSV) and Trabecular Bone Pattern Factor (TBPf)] showed a significant compromising of microarchitecture in these patients. PHPT patients have similar structural parameters to normal subjects. Concerning microarchitecture, indirect approach by MSV and TBPf shows a significant compromising of connectivity. These results can explain trabecular fragility observed in clinical studies on PHPT.


Assuntos
Hiperparatireoidismo Primário/patologia , Ílio/anatomia & histologia , Idoso , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Feminino , Humanos , Hiperparatireoidismo Primário/fisiopatologia , Ílio/fisiologia , Pessoa de Meia-Idade , Pós-Menopausa/fisiologia
5.
Br J Sports Med ; 42(10): 845-9; discussion 849-50, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17545276

RESUMO

OBJECTIVES: A few studies on small patient series have investigated the relationship between gastroesophageal reflux and bronchial responsiveness as expressed by exercise-induced bronchoconstriction (EIB), with non-conclusive results. The aim of this study was to evaluate whether the presence of acid in the oesophagus may influence EIB. METHODS: 45 patients with bronchial asthma underwent spirometry, exercise challenge on bicycle ergometer and 24 h oesophageal pH monitoring. Subjects with EIB (Forced expiratory volume in the first second (FEV1)) percentage decrease after exercise (DeltaFEV1) > or =15%, n = 28) were retested after a 2 week treatment course with omeprazole 40 mg/daily. Exercise at baseline was performed at the same time as oesophageal pH monitoring. RESULTS: In basal condition, there was no difference in FEV1, acid exposure time or number of refluxes measured during 24 h pH monitoring between patients with and without EIB. There was no relationship between spirometry results and DeltaFEV1 on one hand, and parameters of gastroesophageal reflux on the other. Nine patients with EIB (31.0%) and six patients without EIB (37.5%) had one or more episodes of GER during exercise challenge, without significant differences between the two groups. After gastric acid inhibition by omeprazole, DeltaFEV1 did not change significantly. CONCLUSIONS: The results indicate that acid in the oesophagus, or its short-term inhibition by proton pump inhibitors, has no influence on exercise-induced bronchoconstriction.


Assuntos
Asma Induzida por Exercício/etiologia , Exercício Físico/fisiologia , Refluxo Gastroesofágico/complicações , Adulto , Broncoconstrição/fisiologia , Monitoramento do pH Esofágico , Teste de Esforço , Feminino , Humanos , Masculino , Testes de Função Respiratória , Espirometria
6.
J Endocrinol Invest ; 30(9): 739-46, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17993765

RESUMO

UNLABELLED: Osteoporosis is a severe complication of glucocorticoid treatment. Bisphosphonates are a powerful therapeutic option to prevent osteoporotic fractures. The aims of this study were: a) to determine bone alterations induced by therapy with glucocorticoids (GC); b) to establish the efficacy of risedronate (Ris) in the prevention of these effects. We studied 40 female Sprague-Dawley rats randomly divided into 4 groups of treatment, administered 3 times a week sc: 1. CONTROL: vehicle of methylprednisolone (GC) + vehicle of Ris; 2. Ris: Ris 5 mug/kg body weight vehicle of GC; 3. GC: GC 7 mg/kg + vehicle of Ris; 4. GC+Ris: GC 7 mg/kg, Ris 5 microg/kg. Animals were treated for 30 days and then were sacrificed. Densitometry was performed at baseline and at the end of the treatment. Right tibiae were removed for histomorphometric analyses. The GC group showed a 7% decrease in bone density vs controls (p<0.05), while the GC+Ris group was associated with a 3.5% increase in bone density vs controls (p<0.05). In the GC group, histomorphometric evaluations showed reduced bone volume (BV/TV) and thinning of trabeculae (Tb.Th) vs controls (BV/TV: 31+/-1 vs 35+/-1%, p<0.05; Tb.Th: 43+/-2 vs 50+/-3 microm, p<0.01; Ac.f: 1.8+/-0.2 vs 1.6+/-0.3 N/yr). The GC+Ris group had increased BV/TV and Tb.Th, and reduced Ac.f vs the GC group. Ris also maintained trabecular microarchitecture. At the histological level, glucocorticoid-induced osteoporosis was characterized by decreased bone volume, reduced osteoblastic activity, and deterioration of microarchitecture. Ris counteracted these effects both by prolonging osteoblast activity, and by maintaining bone microarchitecture.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Osso e Ossos/patologia , Ácido Etidrônico/análogos & derivados , Glucocorticoides/efeitos adversos , Osteoporose/induzido quimicamente , Osteoporose/prevenção & controle , Animais , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Conservadores da Densidade Óssea/farmacologia , Reabsorção Óssea/tratamento farmacológico , Osso e Ossos/efeitos dos fármacos , Modelos Animais de Doenças , Ácido Etidrônico/farmacologia , Ácido Etidrônico/uso terapêutico , Feminino , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Osteoporose/fisiopatologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Ácido Risedrônico
7.
Biochim Biophys Acta ; 1165(3): 279-87, 1993 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-8418885

RESUMO

Lipid hydroperoxides have been implicated in the pathogenesis of atherosclerosis. This work was therefore set up to obtain a fast and specific chemiluminescent assay for measuring hydroperoxides in native low-density lipoprotein (LDL). The apparatus was a complete HPLC system including two pumps, an autosampler, a computer and a chemiluminescent detector with a T-mixing coil in the place of the column. Samples were injected from the autosampler and mixed with luminescent reagent (3 microM luminol and 1 microM microperoxidase in 0.1 M carbonate buffer (pH 10)) in the T-piece. To generate a calibration curve, linoleic acid hydroperoxide was obtained by incubating soybean lipoxygenase with linoleic acid. The calculated conjugated diene concentration was in good agreement with the nominal linoleic acid hydroperoxide concentration. The chemiluminescence was linear with the amount of linoleic acid hydroperoxide injected and the detection limit was about 3 pmol linoleic acid hydroperoxide. The chemiluminescence induced by copper-oxidized LDL was linear with concentration; the detection limit, when compared with linoleic acid hydroperoxide, was similar. The reproducibility of the linoleic acid hydroperoxide and of oxidized LDL hydroperoxide was examined in single pools. The coefficient of variation on the triplicates of each pool was about 3%. The titre of the linoleic acid hydroperoxide and oxidized LDL peroxides was quite stable for at least 10 days when stored under argon at 4 degrees C in the presence of EDTA. The mean value of the LDL hydroperoxides in 16 control subjects was 145.20 +/- 98.81 pmol/mg LDL protein. In conclusion, the microperoxidase-luminol-dependent chemiluminescence flow-injection assay is a rapid, sensitive and selective method for measuring lipid hydroperoxides in native LDL.


Assuntos
Peróxidos Lipídicos/análise , Lipoproteínas LDL/sangue , Medições Luminescentes , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Cinética , Ácido Linoleico , Ácidos Linoleicos/química , Peroxidação de Lipídeos , Lipoproteínas LDL/química , Lipoxigenase/química , Luminol , Peroxidases
8.
Diabetes ; 47(1): 130-3, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9421387

RESUMO

Troglitazone, an oral antidiabetic agent with antioxidant properties, has previously been shown to increase the resistance of LDL to oxidation in vitro and in vivo in healthy volunteers. In a randomized, placebo-controlled, parallel-group study in 29 patients with NIDDM, we tested the effect of troglitazone (200 mg once daily) on the resistance of LDL to oxidation and on circulating levels of preformed lipid hydroperoxides and the adhesion molecule E-selectin. Resistance of LDL to oxidation was assessed by measuring 1) fluorescence development induced by copper treatment (lag phase), and 2) amount of thiobarbituric acid-reactive substances (TBARS) generated by incubation with umbilical vein endothelial cells. At 8 weeks, the lag phase was increased by 23% (P < 0.01 by analysis of covariance [ANCOVA]) in the patients receiving troglitazone (n = 18) compared with the group receiving placebo (n = 11). At the same time, TBARS were 3.63 +/- 0.10 nmol/l (vs. 5.32 +/- 0.10 nmol/l in the placebo group, P = 0.009), LDL hydroperoxide concentration was reduced from 1.48 +/- 0.03 to 1.19 +/- 0.03 ng/mg (no change in the placebo group, P < 0.01), and plasma E-selectin levels decreased from 56.5 +/- 2.33 to 43.7 +/- 1.77 microg/l (no change in the placebo group, P < 0.01). In NIDDM, troglitazone may slow down the development of atherosclerosis by modifying LDL-related atherogenic events.


Assuntos
LDL-Colesterol/metabolismo , Cromanos/farmacologia , Diabetes Mellitus Tipo 2/sangue , Selectina E/sangue , Hipoglicemiantes/farmacologia , Tiazóis/farmacologia , Tiazolidinedionas , Análise de Variância , Arteriosclerose/prevenção & controle , Cromanos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Método Duplo-Cego , Endotélio Vascular/metabolismo , Feminino , Fluorescência , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oxirredução , Peróxidos/análise , Peróxidos/sangue , Tiazóis/uso terapêutico , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Troglitazona , Vitamina E/administração & dosagem
9.
Micron ; 36(7-8): 609-16, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16242341

RESUMO

The increasing use of densitometric devices for assessing bone fragility has progressively strengthened the assumption that mass is the most important property determining bone mechanical competence. Nevertheless, structure and microarchitecture are relevant aspects of bone strength. The study of microarchitecture is based on the measure of width, number, and separation of trabeculae as well as on their spatial organization. There are several methods to assess bone architecture, particularly at the trabecular level. In particular, histomorphometry, based on the use of optical microscopy and on the principles of quantitative histology and stereology, evaluates microarchitecture two-dimensionally, even if these measures appear well correlated to the three-dimensional structure and properties of bone. In addition, new computerized methods allow the acquisition of more sophisticated measurements by means of a digitizer have been introduced to integrate the use of the microscope. These methods supply information on trabecular width as well as on its distribution and on the organization of the trabeculae in the marrow space. Microarchitecture seems to be a determinant of bone fragility independent of bone density and it is important for understanding the mechanisms of bone fragility as well as the action of the drugs used to prevent osteoporotic fractures. Several in vivo studies (on animals and humans) can provide an additional interpretation for the anti-fracture effect of such drugs. For instance, bisphosphonates and parathyroid hormone seem to preserve or even improve microarchitecture. The challenge for the future will be to evaluate bone quality in vivo with the same or better resolution and accuracy than the invasive methods used today.


Assuntos
Densidade Óssea , Osso e Ossos/citologia , Osso e Ossos/fisiologia , Animais , Fenômenos Biomecânicos , Densidade Óssea/efeitos dos fármacos , Doenças Ósseas/patologia , Doenças Ósseas/fisiopatologia , Osso e Ossos/efeitos dos fármacos , Tecido Conjuntivo/patologia , Tecido Conjuntivo/ultraestrutura , Difosfonatos/farmacologia , Fraturas Ósseas/patologia , Fraturas Ósseas/fisiopatologia , Ósteon/citologia , Ósteon/patologia , Histocitoquímica , Humanos , Processamento de Imagem Assistida por Computador , Osteoporose/patologia , Osteoporose/fisiopatologia , Hormônio Paratireóideo/farmacologia , Ratos
10.
J Bone Miner Res ; 14(8): 1420-4, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10457275

RESUMO

Alterations of the collagen matrix, e.g., increased hydroxylation and glycosylation of lysyl residues in collagen I, were found in human osteoporotic bone, and it was suggested that they could alter the mechanical properties of skeleton. To test this hypothesis, we evaluated the content of galactosyl-hydroxylysine (GHYL) in bone collagen, as assessed by its urinary excretion, and related it to the occurrence of fracture. Two hundred and fifteen unselected postmenopausal women with osteoporosis were divided in two subgroups (comparable for age, age of menopause, bone mineral density, and biochemical parameters of bone turnover) on the basis of the history of fragility fracture; 115 patients had suffered no fracture and 100 patients had suffered one or more fractures 3 or more years before. Four urinary markers of bone turnover (hydroxyproline, cross-linked N-telopeptide, free deoxypyridoline, and GHYL) were evaluated in all patients. There was no difference between the two groups with regard to all the parameters studied except for GHYL, which was significantly higher in the group with a history of fracture (1.35 +/- 0.82 mmol/mol of creatinine [Cr] versus 1.03 +/- <0.48 mmol/mol Cr, p < 0.001); this marker did not correlate with other markers of bone remodeling in the fracture group, indicating a possible defect in bone collagen. In conclusion, provided that increased levels of urinary GHYL do reflect overglycosylation of hydroxylysine in bone collagen, the GHYL may be considered a marker of bone collagen quality. Our results, showing higher urinary GHYL in osteoporosis patients with fracture, seem to confirm this suggestion.


Assuntos
Densidade Óssea/fisiologia , Hidroxilisina/análogos & derivados , Osteoporose Pós-Menopausa/urina , Idoso , Biomarcadores/urina , Fenômenos Biomecânicos , Colágeno/química , Feminino , Humanos , Hidroxilisina/urina , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Free Radic Biol Med ; 16(4): 459-63, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8005531

RESUMO

The determination of lipid hydroperoxides in plasma and lipoproteins recently reached a clinical relevance in disorders such as atherosclerosis, where oxidative reactions have been suggested to play a fundamental pathogenetic role. The peroxide content of lipoproteins is usually measured after ultracentrifugation and extraction. During this procedure, some peroxides might decompose causing a too low recovery. To screen this possibility, the disappearance, in the presence of human plasma, of hydroperoxides of linoleic acid and Cu-oxidized low density lipoprotein (LDL) have been investigated, using both a iodometric titration and an enzymatic assay. While only in the presence of GSH plasma decomposes linoleic acid hydroperoxides quite rapidly, peroxides in Cu-oxidized LDL were stable both in presence as well as in absence of GSH. This indicated that lipid hydroperoxides are stable in plasma and that peroxides of Cu-oxidized LDL are not substrate for the glutathione-dependent peroxidase activity in plasma. The relevant decrease of the iodometric titre of LDL peroxides observed in the presence of elevated amounts of plasma was shown to be artifactual, since some compounds extracted from plasma do react with iodine generated by peroxides. Whole plasma itself, indeed, has been shown to reduce back to I- appreciable amount of free iodine.


Assuntos
Cobre/farmacologia , Ácidos Linoleicos/sangue , Peróxidos Lipídicos/sangue , Lipoproteínas LDL/metabolismo , Glutationa/farmacologia , Humanos , Cinética , Lipoproteínas LDL/efeitos dos fármacos , Oxirredução , Peroxidases/sangue , Valores de Referência , Especificidade por Substrato , Fatores de Tempo
12.
Free Radic Biol Med ; 22(1-2): 117-27, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-8958136

RESUMO

The oxidative modification of low density lipoprotein (LDL) and the endothelial expression of adhesion molecules are key events in the pathogenesis of atherosclerosis. In this study we evaluated the effect of oxidized LDL on the expression of intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin on human umbilical vein endothelial cells (HUVECs). The hypothesis that oxidized LDL functions as a prooxidant signal was also evaluated, by studying the effect of different radical-scavenging antioxidants on expression of adhesion molecules. LDL was oxidized by using Cu2+, HUVECs or phospholipase A2 (PLA2)/ soybean lipoxygenase (SLO), the degree of oxidation being measured as thiobarbituric acid-reactive substances (TBARS) and conjugated dienes (CD). Exposure of 200 micrograms/ml of native LDL to 1 microns Cu2+, HUVECs and to PLA2/ SLO resulted in four- to fivefold higher levels of TBARS and CD than in native LDL. Cu(2+)-(1 microM), HUVEC-, and PLA2/SLO-oxidized LDL caused a dose-dependent, significant increase of ICAM-1 and VCAM-1 (p < .01). The expression of E-selectin did not change. LDL oxidized with a 2.5 and 5 microM Cu2+ did not increase ICAM-1 and VCAM-1 significantly. Both the Cu(2+)- and HUVEC-oxidized LDL, subjected to dialysis and ultrafiltration, induced ICAM-1 and VCAM-1 expression. After incubation with the ultrafiltrate, the expression of ICAM-1 and VCAM-1 was not significantly different from that obtained with native LDL. LDL pretreated with different antioxidants (vitamin E and probucol) and subjected to oxidation by Cu2+ and HUVECs induced a significantly lower expression of ICAM-1 and VCAM-1 than nonloaded LDL (p < .01). The pretreatment of HUVECs with vitamin E and probucol significantly reduced the expression of VCAM-1 on HUVECs induced by oxidized LDL (p < .01); the effect on ICAM-1 was much less evident. In conclusion, oxidized LDL can induce the expression of different adhesion molecules on HUVECs; this induction can be prevented by pretreating either the LDL or the cells with radical-scavenging antioxidant.


Assuntos
Antioxidantes/farmacologia , Endotélio Vascular/efeitos dos fármacos , Molécula 1 de Adesão Intercelular/biossíntese , Lipoproteínas LDL/farmacologia , Molécula 1 de Adesão de Célula Vascular/biossíntese , Células Cultivadas , Diálise , Selectina E/biossíntese , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Sequestradores de Radicais Livres/farmacologia , Radicais Livres , Humanos , Oxirredução , Espécies Reativas de Oxigênio , Ultrafiltração , Veias Umbilicais/citologia , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/metabolismo
13.
Bone ; 15(4): 415-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7917580

RESUMO

Twenty patients with mild Paget's disease of bone were given either 20 (10 patients) or 40 mg alendronate daily for 6 months. The 20-mg dose was well tolerated, but in 3 patients on 40 mg/d alendronate, the treatment was withdrawn after 3-5 months because of gastric and oesophageal disturbances. Urinary hydroxyproline excretion fell within the first month to 77 +/- 5% (SD) and to 47 +/- 5% of pretreatment values in the 20- and 40-mg dosing group, respectively (p < 0.001 between group comparison). The serum alkaline phosphatase fell more slowly with the maximum suppression of disease activity reached at 4 months, when it attained a plateau in both groups of patients. However, the decrease in serum alkaline phosphatase was significantly more pronounced in the patients treated with 40 mg/d tablets (50 +/- 10% of pretreatment values) than in those given 20 mg alendronate per day (76 +/- 9% of initial value), in none of whom a disease remission was observed. It appears, therefore, that while 20 mg/d oral doses of alendronate are insufficient, 40 mg/d are associated with a high incidence of side effects. Furthermore, the suppression of disease activity depends on the dose of bisphosphonate given daily or over a short period of time and lower doses cannot be compensated by a longer duration of the treatment course.


Assuntos
Difosfonatos/uso terapêutico , Osteíte Deformante/tratamento farmacológico , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Alendronato , Fosfatase Alcalina/sangue , Análise de Variância , Difosfonatos/administração & dosagem , Difosfonatos/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Humanos , Hidroxiprolina/urina , Masculino , Pessoa de Meia-Idade
14.
J Hypertens ; 16(12 Pt 2): 1913-9, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9886877

RESUMO

OBJECTIVE: The mechanisms by which oxidized low-density lipoprotein (ox-LDL) induces the expression of adhesion molecules on endothelial cells (HUVECs) are still not clear. The signal transduction pathways for these binding molecules include the translocation of the transcription factor NF-kB and the intracellular reactive oxygen species (ROS) are said to play a key role in this process. Aim of this study was (1) to evaluate the effect of ox-LDL on intracellular production of ROS in culture of HUVECs; (2) to evaluate if the intracellular increase of ROS induced by ox-LDL is mediated by the binding to a specific endothelial receptor; (3) to ascertain if lacidipine can decrease ox-LDL-induced ROS production in HUVECs. METHODS: Five microM Cu2+ ox-LDL were incubated with HUVECs for 5 min. 2',7'-Dichlorofluorescein (DCF) as an expression of intracellular ROS production, was measured by flow cytometry. RESULTS: ox-LDL induced a significant dose-dependent increase in DCF production (P < 0.001) through the binding to a specific receptor. The preincubation of HUVECs with radical scavengers compounds and lacidipine significantly reduced (P < 0.001) the ox-LDL-induced DCF production. CONCLUSIONS: ox-LDL increased the intracellular formation of ROS through the ligation to a specific endothelial receptor. Preincubation of HUVECs with lacidipine, a calcium antagonist with antioxidant properties, significantly reduced the intracellular ROS formation induced by ox-LDL. We propose that the effect of lacidipine on adhesion molecule expression and on NF-kB activation can be explained by its effect on intracellular ROS formation.


Assuntos
Di-Hidropiridinas/farmacologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Lipoproteínas LDL/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Arteriosclerose/etiologia , Arteriosclerose/prevenção & controle , Bloqueadores dos Canais de Cálcio/farmacologia , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Fluoresceínas , Corantes Fluorescentes , Humanos , Líquido Intracelular/metabolismo , Lipoproteínas LDL/metabolismo , NF-kappa B/metabolismo , Oxirredução
15.
J Hypertens ; 15(12 Pt 2): 1633-40, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9488215

RESUMO

OBJECTIVE: The adhesion of monocytes to endothelium, an early event in atherosclerosis is mediated by cell adhesion molecules. Signal-transduction pathways for these binding molecules include the translocation of the transcription factor NF-kappaB; moreover, intracellularly generated oxygen-derived free radicals play a major role in this process. In this study we evaluated the extent to which lacidipine, a calcium antagonist with antioxidant properties, affects the expression of intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin on human umbilical vein endothelial cells, induced by different pro-oxidant signals such as oxidized low density lipoprotein (LDL) and tumor necrosis factor-alpha (TNF-alpha). METHODS: We incubated 5 micromol/l Cu2+-oxidized LDL and TNF-alpha (2 ng/ml) with human umbilical vein endothelial cells for 48 and 6 h, respectively. ICAM-1, VCAM-1 and E-selectin were measured by flow cytometry. NF-kappaB was evaluated by electrophoretic mobility shift assay. RESULTS: The incubation of 5 micromol/l Cu2+-oxidized LDL not only caused a dose-dependent increase in ICAM-1, VCAM-1 and E-selectin (P < 0.001), but also synergically increased their TNF-alpha-induced expression (P < 0.001). The addition of lacidipine to human umbilical vein endothelial cells significantly reduced the expression of ICAM-1, VCAM-1 and E-selectin induced by TNF-alpha alone or with oxidized LDL (P < 0.001). The reduction in adhesion molecule expression caused by lacidipine was paralleled by a significant fall in NF-kappaB translocation. CONCLUSIONS: The results suggest that lacidipine may have prevented NF-kappaB-mediated adhesion molecule expression by exerting its effects on oxygen-derived free radicals. The results support previous observations that lacidipine may have therapeutic effects in atherosclerosis.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Moléculas de Adesão Celular/metabolismo , Di-Hidropiridinas/farmacologia , Endotélio Vascular/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Endotélio Vascular/metabolismo , Humanos , Oxirredução , Veias Umbilicais/citologia
16.
Clin Chim Acta ; 204(1-3): 57-68, 1991 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-1819474

RESUMO

The predisposition to LDL oxidation during copper-catalyzed oxidative modification and its relationship with LDL alpha-tocopherol concentration was studied in 41 control subjects. The results show that the predisposition of LDL to oxidation expressed as duration of the inhibition period and rate of the propagation period varied greatly in the controls, but did not correlate with the values of LDL alpha-tocopherol. On the contrary the experiments with alpha-tocopherol incorporated in LDL demonstrate that even small increases of incorporated alpha-tocopherol, under circumstances where other variables were probably largely unaffected, increased proportionally the length of the inhibition period and reduced the rate of the propagation period. The values of LDL alpha-tocopherol achieved after the enrichment turned out to be positively correlated with the duration of the inhibition period and negatively with the rate of the propagation period. Finally the results of this study also show that there was a variability in the LDL alpha-tocopherol decay of different subjects under the same oxidative stress. In our conditions however, the time in which alpha-tocopherol contributed to the LDL protection was much shorter than the mean length of the inhibition period. The results demonstrate that the variability in the predisposition to LDL oxidation during copper-catalyzed oxidative modification is not determined only by the concentration of alpha-tocopherol in LDL and that therefore its value as a sole indicator of antioxidant status is probably inadequate.


Assuntos
Cobre/metabolismo , Lipoproteínas LDL/sangue , Vitamina E/sangue , Antioxidantes , Sulfato de Cobre , Humanos , Cinética , Oxirredução
17.
Maturitas ; 17(3): 191-6, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8133793

RESUMO

The transdermal and oral administration of estrogens for one year were compared with respect to the effects on lipid metabolism. Eighty-one postmenopausal women (1.5-3 years after menopause) were randomly divided into three groups. The first two groups received sequential estrogen treatment with either transdermal estradiol (Estraderm TTS, Ciba Geigy; 50 micrograms/day; 24 women) or 0.625 mg/day conjugated estrogens (Premarin, Wyeth; 20 subjects), respectively. In both groups medroxyprogesterone (10 mg/day per os) was added for 12 days of each cycle. Thirty-five subjects served as control group without therapy. No significant changes in the lipid profile was observed in control subjects after 1 year of follow-up. Serum triglycerides decreased significantly (-10.9 +/- 26% S.D.; P < 0.05) in transdermal treated women, whereas it slightly rose in oral estrogen group. Comparable significant decreases in total and low density lipoprotein (LDL) cholesterol (mean range -6.5/-18.0%) were observed in women on estrogen replacement therapy. High density lipoprotein (HDL) cholesterol significantly diminished in transdermal estradiol group, but it rose slightly in the oral estrogen group. Thus the fraction of HDL cholesterol over LDL cholesterol did not change in the transdermal group whereas it significantly rose in subjects treated with oral estrogens. It remains to be established to what extent these differences on lipid metabolism are relevant for the prevention of cardiovascular diseases.


Assuntos
Terapia de Reposição de Estrogênios , Lipídeos/sangue , Lipoproteínas/sangue , Pós-Menopausa/sangue , Administração Cutânea , Administração Oral , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estradiol/administração & dosagem , Terapia de Reposição de Estrogênios/métodos , Estrogênios Conjugados (USP)/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Triglicerídeos/sangue
18.
Pathol Res Pract ; 185(5): 786-9, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2696954

RESUMO

Diagnostic sensitivity of bone histomorphometry was assessed in different metabolic bone diseases, after fixing the specificity at 75%, 90% and 95% reference levels. Sensitivity was particularly high in cases with greatly increased osteoid and/or resorption features, as in renal osteodystrophy (ROD). All the remodeling indicators were highly sensitive toward advanced or severe forms of mixed ROD (mROD). Osteoid indicators were the most sensitive parameters in ROD with predominant osteomalacia (oROD). Osteoclastic and several osteoid indicators were very sensitive in all grades of ROD with predominant hyperparathyroidism (hROD). Sensitivity was generally low in uremic patients without bone changes (wROD) and also in patients with idiopathic osteoporosis (OP). It is our recommendation, however, that for each individual patient the definite diagnosis should be based on both morphological, clinical and metabolic parameters.


Assuntos
Doenças Ósseas Metabólicas/patologia , Osso e Ossos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/patologia , Análise de Variância , Distúrbio Mineral e Ósseo na Doença Renal Crônica/patologia , Feminino , Humanos , Hiperparatireoidismo/patologia , Masculino , Pessoa de Meia-Idade , Osteomalacia/patologia , Osteoporose/patologia , Valores de Referência , Análise de Regressão , Sensibilidade e Especificidade
19.
Artigo em Inglês | MEDLINE | ID: mdl-11108443

RESUMO

The clinical efficacy of local nasal immunotherapy (LNIT) in patients with allergic rhinitis is amply documented. The aim of the study was to determine the effect on bronchial hyperresponsiveness (BHR) assessed at baseline and after 3 years of LNIT or pharmacological treatment alone. Forty-three randomized patients with allergic oculorhinitis were enrolled (26 positive to Graminaceae and 17 to Parietaria judaica pollens). All patients were asked whether they were willing to follow a 3-year treatment course involving preseasonal LNIT with a powder extract of Graminaceae or Parietaria pollens. Twenty-four patients (16 allergic to Graminaceae and eight to Parietaria) selected LNIT and the other 19 opted for symptomatic pharmacological treatment only. The latter was considered the control group. On the basis of positive or negative bronchial hyperresponsiveness and the LNIT, four subgroups were established and followed in open conditions, during which a record was kept of symptom scores, drug use, spirometry and methacholine test findings. After 3 years, patients treated with LNIT had a significant reduction of symptoms and drug intake. In the controls, symptoms worsened, thus requiring more drugs to control them. Bronchial hyperresponsiveness significantly improved in hyperreactive patients receiving LN7IT 10 of whom were no longer hyperreactive and one at a higher threshold. Among controls, bronchial hyperresponsiveness did not change, with the exception of three nonreactive patients who became hyperreactive, one of them with asthma. These findings confirm the efficacy of LNIT in allergic rhinitis suggesting that it might have systemic activity interfering with bronchial hyperresponsiveness and hence the onset of bronchial asthma.


Assuntos
Hiper-Reatividade Brônquica/terapia , Rinite Alérgica Sazonal/terapia , Administração Intranasal , Adolescente , Adulto , Criança , Feminino , Volume Expiratório Forçado , Humanos , Imunoterapia , Masculino , Pessoa de Meia-Idade , Projetos Piloto
20.
Minerva Med ; 70(32): 2251-64, 1979 Jul 14.
Artigo em Italiano | MEDLINE | ID: mdl-379703

RESUMO

The incidence of thyroid diseases was evaluated in patients with primary hyperparathyroidism subjected to parathyroidectomy. Eleven patients (26.8%) were affected in this way: 2 with carcinoma, 5 with nodular goitre, and 4 with adenoma. The possible reasons for associations of this kind are discussed, and it is suggested that their high frequency points to a relationship of cause and affect.


Assuntos
Hiperparatireoidismo/complicações , Doenças da Glândula Tireoide/etiologia , Adenoma/diagnóstico , Adenoma/etiologia , Ensaios Clínicos como Assunto , Feminino , Bócio Nodular/diagnóstico , Bócio Nodular/etiologia , Humanos , Masculino , Doenças da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/etiologia
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