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1.
J Environ Manage ; 347: 119088, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37812904

RESUMO

Understanding the interactions between human and environmental systems is key to sustainable environmental management. Dynamically Coupled Socioeconomic system dynamics models integrated with physically-based Environmental Models (DCSEMs) are promising tools to appropriately capture the non-linear relationships between complex socioeconomic and biophysical systems, thereby supporting sustainable environmental management. However, existing approaches for testing integrated models are commonly based on the point-to-point analysis of model outputs, which is not suitable for DCSEMs that are behaviour pattern oriented. Consequently, the lack of well-defined behaviour pattern-based approaches has limited the adaptability of DCSEMs. To address this gap, this study proposes a novel behaviour pattern-based model testing approach that includes global sensitivity analysis (GSA), auto-calibration algorithms, and evaluation to assess behaviour pattern similarities between model outputs and real-world trends. The proposed approach is demonstrated through a real-world case study, in which an existing DCSEM is calibrated and evaluated to simulate water table depth in the Rechna Doab region of Pakistan. Compared to the conventional numerical point approach, the proposed approach is better suited for DCSEMs, as it replicates observed system behaviour patterns (as opposed to observed point values) over time. Furthermore, the outcomes of the Theil inequality statistical analysis and parameter distribution analysis provide evidence that the suggested approach is effective in testing and improving the performance of the DCSEM by capturing the spatial heterogeneity within the study area. The proposed behaviour-pattern testing procedure is a useful approach for model testing in data-limited, spatially-distributed DCSEMs.


Assuntos
Água Subterrânea , Modelos Teóricos , Humanos , Fatores Socioeconômicos , Paquistão
2.
Front Pharmacol ; 13: 867709, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784715

RESUMO

Lamiaceae species are rich sources of biologically active compounds which have been applied in medicine since ancient times. Especially their antineoplastic properties have been thoroughly studied with respect to their putative application in chemoprevention and adjuvant therapy of cancer. However, the most known biological effects of Lamiaceae have been ascribed to their essential oil fractions, whereas their (poly)phenolic metabolites being also abundant in these plants, are much less recognized, nevertheless contributing to their beneficial properties, such as anti-cancer actions. The aim of this study was to evaluate the impact of dried aqueous extracts from common thyme (Thymus vulgaris L.) (ExTv), wild thyme (Thymus serpyllum L.) (ExTs), sweet marjoram (Origanum majorana L.) (ExOm), and peppermint (Mentha × piperita L.) (ExMp), as well as (poly)phenolic compounds: caffeic acid (CA), rosmarinic acid (RA), lithospermic acid (LA), luteolin-7-O-ß-glucuronide (Lgr), luteolin-7-O-rutinoside (Lr), eriodictyol-7-O-rutinoside (Er), and arbutin (Ab), on unstimulated Jurkat cells, in comparison with their effect on staurosporine-stimulated Jurkat cells. Jurkat T cells were incubated with different concentrations of ExTv, ExTs, ExOm, ExMp, Lgr, LA, Er, Lr, RA, CA, or Ab. Subsequently, staurosporine was added to half of the samples and flow cytometry combined with fluorescence-activated cell sorting analysis was conducted, which allowed for the selection of early and late apoptotic cells. Both ExTs and ExOm stimulated apoptosis of Jurkat cells and enhanced the proapoptotic effect of staurosporine. Conversely, ExTv and ExMp demonstrated no clear effect on apoptosis. CA and RA raised the staurosporine-induced apoptotic effect. The impact of Er and Lgr on Jurkat cells showed fluctuations depending on the compound concentration. Neither Er nor Ab altered staurosporine-induced apoptosis in Jurkat cells, whereas Lgr seemed to weaken the proapoptotic action of staurosporine. The most evident observation in this study was the pro-apoptotic action of ExTs and ExOm observed both in staurosporine-unstimulated and stimulated Jurkat cells. Additionally, an enhancement of staurosporine-induced apoptosis by caffeic and rosmarinic acids was reported. Therefore, it might be concluded that these are the mixtures of biologically active polyphenols which often exert more pronounced beneficial effects than purified molecules.

3.
Adv Clin Exp Med ; 29(1): 71-78, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31967744

RESUMO

BACKGROUND: Paraoxonase 1 (PON1) is an enzyme with the capability to protect against lipid oxidation and atherosclerotic lesions formation. Impaired antioxidative capacity and enhanced lipid peroxidation (reflected by malondialdehyde rise) accompany dementias. OBJECTIVES: The aim of this study was to discern the possible differences in the activity and phenotype distribution of PON1, and lipid peroxidation level in dementias of neurodegenerative and vascular pathology, to assess whether they reflect structural changes in the brain, and to evaluate their potential as dementia markers. MATERIAL AND METHODS: Paraoxonase 1 arylesterase activity and polymorphisms (dual-substrate method), and malondialdehyde/thiobarbituric acid reactive substances (MDA/TBARS) levels were determined spectrophotometrically in 257 serum samples derived from 136 dementive patients (with Alzheimer's disease (AD; n = 63), vascular dementia (VaD; n = 40) and mixed-type dementia (MD; n = 33), as well as from 121 non-dementive individuals. The results were analyzed with reference to dementia type and severity (assessed with Mini Mental State Examination (MMSE) and Clinical Dementia Rating (CDR) scales), structural brain changes (estimated with magnetic resonance imaging (MRI) - Global Cortical Atrophy (GCA), Medial Temporal lobe Atrophy (MTA) and Fazekas scales)) and brain ischemia (Hachinski Ischemic Scale (HIS) index), and evaluated using receiver operating characteristic (ROC) analysis. RESULTS: Malondialdehyde/thiobarbituric acid reactive substances were increased in dementia (more in VaD than AD). In patients with vascular involvement, MDA/TBARS elevation reflected a degree of global cortical atrophy. Paraoxonase 1 activity was decreased in patients with dementia, especially in patients with severe cognitive deficits. In VaD, a drop in PON1 reflected a degree of MTA and brain ischemia. MDA/TBARS displayed 75% accuracy as a general dementia marker, but, similarly to PON1, were a poor differential marker. CONCLUSIONS: Both indices were more associated with vascular involvement and the severity of brain atrophy or ischemia rather than with degree of cognitive decline.


Assuntos
Doença de Alzheimer , Arildialquilfosfatase , Encéfalo , Disfunção Cognitiva , Demência Vascular , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/enzimologia , Doença de Alzheimer/patologia , Arildialquilfosfatase/metabolismo , Atrofia , Encéfalo/patologia , Demência Vascular/enzimologia , Demência Vascular/patologia , Feminino , Humanos , Peroxidação de Lipídeos , Imageamento por Ressonância Magnética , Masculino
4.
Peptides ; 122: 170169, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31563540

RESUMO

Hepcidin is a peptide hormone regulating iron metabolism, the dyshomeostasis of which has been implicated in dementia. Yet, data on hepcidin status in dementia are scanty, limited to Alzheimer's disease (AD) and inconsistent due to methodological problems with its determination using immunoassays and/or lack of homogeneity of evaluated groups. Hepcidin association with vascular dementia (VaD) remains unknown. We proposed a mass spectrometry method of hepcidin quantification in sera and aimed at determining hepcidin systemic status in patients with dementia of AD, VaD, or mixed (MD) pathology, with reference to the degree of cognitive loss and structural changes in the brain as well as at evaluating the diagnostic potential of hepcidin as a biomarker. We found that hepcidin concentrations were significantly elevated in VaD and insignificantly so in AD or MD and that they positively correlated with the Clinical Dementia Rating and inversely with the Mini Mental State Examination. Hepcidin tended to be more pronouncedly elevated in patients with advanced cortical atrophy and white matter lesions. It displayed a biphasic relationship with the Hachinski Ischemic Scale and a good accuracy as dementia but not differential marker. Taken together, our results demonstrated that dementia of vascular and not neurodegenerative pathology is associated with significant elevation of systemic hepcidin. Hepcidin elevation reflects the degree of cognitive loss as well as the severity of structural changes in the brain. If confirmed in a prospective study, hepcidin quantification may hold promise as a diagnostic marker; its accuracy as a differential marker of VaD is insufficient.


Assuntos
Doença de Alzheimer/genética , Encéfalo/fisiopatologia , Demência/genética , Hepcidinas/genética , Idoso , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/fisiopatologia , Biomarcadores/sangue , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Cromatografia Líquida , Demência/sangue , Demência/diagnóstico por imagem , Demência/fisiopatologia , Feminino , Hepcidinas/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem , Substância Branca/diagnóstico por imagem , Substância Branca/fisiopatologia
5.
Food Chem ; 141(2): 1313-21, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23790919

RESUMO

The aim of this study was to evaluate the cytotoxicity of dried aqueous extracts from Thymus serpyllum (ExTs), Thymus vulgaris (ExTv), Majorana hortensis (ExMh), and Mentha piperita (ExMp), and the phenolic compounds caffeic acid (CA), rosmarinic acid (RA), lithospermic acid (LA), luteolin-7-O-glucuronide (Lgr), luteolin-7-O-rutinoside (Lr), eriodictiol-7-O-rutinoside (Er), and arbutin (Ab), on two human breast cancer cell lines: Adriamycin-resistant MCF-7/Adr and wild-type MCF-7/wt. In the MTT assay, ExMh showed the highest cytotoxicity, especially against MCF-7/Adr, whereas ExMp was the least toxic; particularly against MCF-7/wt cells. RA and LA exhibited the strongest cytotoxicity against both MCF-7 cell lines, over 2-fold greater than CA and Lgr, around 3-fold greater than Er, and around 4- to 7-fold in comparison with Lr and Ab. Except for Lr and Ab, all other phytochemicals were more toxic against MCF-7/wt, and all extracts exhibited higher toxicity against MCF-7/Adr. It might be concluded that the tested phenolics exhibited more beneficial properties when they were applied in the form of extracts comprising their mixtures.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Neoplasias da Mama/fisiopatologia , Lamiaceae/química , Fenóis/toxicidade , Extratos Vegetais/toxicidade , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Células MCF-7
6.
Inflamm Bowel Dis ; 16(9): 1467-75, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20186929

RESUMO

BACKGROUND: Oxidative stress contributes to the propagation and exacerbation of inflammatory bowel disease (IBD) but the status of erythrocyte antioxidant defense remains unknown. METHODS: Erythrocyte activities of superoxide dismutase-1 (SOD1), catalase, and glutathione peroxidase-1 (GPx1) were determined in 174 IBD patients and 105 controls and referred to IBD activity, inflammation severity, nutritional status, systemic oxidative stress, anemia, and treatment. RESULTS: Catalase and GPx1 activities were decreased in active IBD, whereas SOD1 became upregulated by IBD-related oxidative stress. In Crohn's disease (CD) corticosteroids decreased SOD1 activity. SOD1 correlated indirectly with CD activity and erythrocyte sedimentation rate (ESR) and directly with transferrin. In ulcerative colitis (UC) anemia downregulated SOD1. Decreases in GPx activity corresponded with IBD activity, anemia, inflammation, and malnutrition. Oxidative stress in UC and corticosteroids in CD also downregulated GPx. Catalase activity was decreased by CD-related anemia, correlating directly with hemoglobin, and indirectly with CD activity, inflammatory and protein oxidative stress markers. When co-analyzed, anemia but not CD activity significantly contributed to catalase downregulation. In UC, catalase activity corresponded indirectly with UC endoscopic activity and inflammation and directly with hemoglobin. UC activity, anemia, and treatment with azathioprine negatively affected catalase. As indicators of active IBD, GPx1 showed a diagnostic accuracy of 73%, whereas catalase showed 63% as compared to 74% of C-reactive protein and ESR. CONCLUSIONS: Erythrocyte antioxidant defense is impaired in active IBD. SOD1, GPx1, and CAT activities are differently affected by the disease type, activity, anemia, inflammation, oxidative stress, and treatment. As an active IBD indicator, GPx1 was comparable to C-reactive protein and ESR.


Assuntos
Anemia/sangue , Antioxidantes/metabolismo , Colite Ulcerativa/sangue , Doença de Crohn/sangue , Membrana Eritrocítica/enzimologia , Oxirredutases/metabolismo , Adolescente , Adulto , Idoso , Sedimentação Sanguínea , Estudos de Casos e Controles , Catalase/metabolismo , Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Doença de Crohn/metabolismo , Feminino , Glutationa Peroxidase/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Adulto Jovem , Glutationa Peroxidase GPX1
7.
Inflamm Bowel Dis ; 15(1): 93-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18626964

RESUMO

BACKGROUND: Paraoxonase 1 (PON1) is an extracellular enzyme, which in the gastrointestinal tract may act as a local detoxifier, antioxidant, immunomodulator, and/or quorum-quenching factor. There are no data on PON1 activity in Crohn's disease (CD). METHODS: PON1 phenotype and activity were determined spectrophotometrically in 52 subjects with CD, 67 with ulcerative colitis (UC), and 99 healthy individuals, and related to lipid peroxidation and disease phenotype, clinical and biochemical activity, and therapeutic strategy. Diagnostic utility of PON1 was evaluated by ROC analysis and compared with C-reactive protein (CRP). RESULTS: In comparison with controls (166 U), PON1 was reduced only in active CD (110 U, P < 0.0001) and UC (126 U, P < 0.0001), and correlated with disease activity (r = -0.47, P = 0.001 in CD and r = -0.50, P < 0.001 in UC). PON1 significantly correlated with erythrocyte sedimentation rate (ESR) (r = -0.36), platelets (r = -0.35), interleukin-6 (r = -0.45), hemoglobin (r = 0.29), transferrin (r = 0.46), albumin (r = 0.60) in CD, and CRP (r = -0.29), ESR (r = -0.37), platelets (r = -0.43), leukocytes (r = -0.50), interleukin-6 (r = -0.45), hemoglobin (r = 0.34), transferrin (r = 0.54), and albumin (r = 0.50) in UC. PON1 correlated positively with lipids but not with their peroxidation markers (thiobarbituric acid-reactive substances, lipid hydroperoxides, ox-LDL, and ox-LDL autoantibodies). PON1 phenotype B (protective against IBD) tended to be less frequent in IBD patients than controls, and associated with lower concentration of inflammatory indices. PON1 was a poorer indicator of CD or UC than CRP. CONCLUSIONS: PON1 was reduced in IBD, despite treatment with antioxidant 5'-aminosalicylate derivatives. PON1 reflected disease activity, inflammation severity, and anemia but not lipid peroxidation. The diagnostic power of PON1 was insufficient for its clinical application.


Assuntos
Arildialquilfosfatase/metabolismo , Biomarcadores/metabolismo , Colite Ulcerativa/enzimologia , Doença de Crohn/enzimologia , Adolescente , Adulto , Idoso , Proteína C-Reativa/metabolismo , Colite Ulcerativa/diagnóstico , Doença de Crohn/diagnóstico , Feminino , Hemoglobinas/metabolismo , Humanos , Inflamação , Interleucina-6/metabolismo , Contagem de Leucócitos , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Fenótipo , Curva ROC , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Transferrina/metabolismo , Adulto Jovem
8.
Clin Biochem ; 41(12): 943-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18501708

RESUMO

OBJECTIVES: To evaluate the formation of advanced oxidation protein products (AOPPs) in juvenile overweight/obesity and obesity-related disorders and to investigate the effect of weight reduction on AOPPs. DESIGN AND METHODS: AOPPs were determined in 114 overweight/obese children and adolescents without/with insulin resistance and metabolic syndrome and compared with 53 lean controls. Measurements were repeated following weight reduction program (diet/exercise, bran-enriched diet/exercise, and diet/exercise plus metformin). RESULTS: Overweight/obese subjects had higher AOPPs than lean controls, more elevated in patients with co-occurring metabolic syndrome. AOPPs positively correlated with central obesity, triglycerides, lipid peroxidation and insulin, and negatively with glucose to insulin ratio. AOPPs decreased following obesity intervention and DeltaAOPPs correlated with DeltaBMI%. AOPPs reduction was more pronounced in subjects on bran-enriched diet. Baseline AOPPs were a better predictor of clinically significant weight reduction than BMI%. CONCLUSIONS: Juvenile overweight/obesity was associated with AOPPs accumulation, more pronounced in metabolic syndrome. Body mass reduction decreased oxidative stress, with bran-enriched diet being more effective than diet/exercise alone.


Assuntos
Proteínas Sanguíneas/metabolismo , Obesidade/metabolismo , Sobrepeso/metabolismo , Redução de Peso , Adolescente , Análise de Variância , Glicemia/metabolismo , Índice de Massa Corporal , Colesterol/sangue , Feminino , Humanos , Insulina/sangue , Masculino , Síndrome Metabólica/metabolismo , Obesidade/dietoterapia , Sobrepeso/dietoterapia , Oxirredução , Estresse Oxidativo , Análise de Regressão , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Triglicerídeos/sangue
9.
Clin Biochem ; 41(1-2): 48-55, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18246609

RESUMO

OBJECTIVES: To validate the diagnostic utility of oxidative stress markers in the evaluation of young type 1 diabetics, as suggested elsewhere. DESIGN: Advanced oxidation protein products (AOPP), thiobarbituric acid-reactive substances (TBARS) and total antioxidant status (TAS) were measured in sera from diabetics, their siblings and controls, with diagnostic potential evaluated by ROC analysis, and related to diabetes clinical parameters. RESULTS: In diabetics AOPP and TBARS were elevated, TAS decreased. Similar alterations were observed for AOPP and TAS in their siblings. AOPP and TAS were good indicators of diabetes. AOPP and TBARS correlated with HbA1C (independent predictor), but were poor markers of non-adequate glycemic control. The cardiovascular disease risk factors were independent predictors of TBARS concentrations. CONCLUSIONS: AOPP accumulation and TAS reduction seem to precede diabetes and might be considered as susceptibility indicators in relatives, but not as diabetes markers in general population (no diabetes specificity has been shown). Application in monitoring of metabolic control is not validated.


Assuntos
Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/metabolismo , Angiopatias Diabéticas/diagnóstico , Estresse Oxidativo/fisiologia , Estado Pré-Diabético/diagnóstico , Adolescente , Biomarcadores/análise , Glicemia/análise , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Estudos de Casos e Controles , Criança , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Angiopatias Diabéticas/metabolismo , Feminino , Hemoglobinas Glicadas/análise , Produtos Finais de Glicação Avançada/sangue , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Masculino , Estado Pré-Diabético/sangue , Estado Pré-Diabético/metabolismo , Fatores de Risco , Sensibilidade e Especificidade , Irmãos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de Tempo
10.
Inflamm Bowel Dis ; 14(6): 794-802, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18213700

RESUMO

BACKGROUND: Advanced oxidation protein products (AOPPs) are new protein markers of oxidative stress with pro-inflammatory properties, accumulated in many pathological conditions. The issue of their enhanced formation in IBD has not been addressed yet. METHODS: The concentration of relative AOPPs (rAOPP; concentration of AOPPs divided by albumin level) were measured in 68 subjects with ulcerative colitis (UC), 50 subjects with Crohn's disease (CD) and 45 healthy volunteers, and related to disease phenotype, clinical and biochemical activity, and therapeutic strategy. Diagnostic utility of rAOPP was evaluated by ROC analysis. RESULTS: In comparison with controls (1.367 micromol/g), rAOPP were increased in inactive (1.778 micromol/g, P = 0.053) and active (1.895 micromol/g, P = 0.013) UC and in active (1.847 micromol/g, P = 0.003) CD. In CD, but not UC, rAOPP correlated with disease activity (r = 0.42, P = 0.013). Significant correlations with the inflammatory/malnutrition indices-erythrocyte sedimentation rate (ESR) (r = 0.53), leukocytes (r = 0.33), platelets (r = 0.38), IL-6 (r = 0.36), and transferrin (r = -0.35) were demonstrated in CD. In UC, rAOPP correlated only with ESR (r = 0.35) and IL-6 (r = 0.30). Instead, associations with antioxidant dismutase (r = 0.29) and catalase (r = 0.22) were observed. The diagnostic power of rAOPP in discriminating diseased from non-diseased subjects was less than that of C-reactive protein (CRP). Simultaneous determination of rAOPP and CRP did not significantly improve the power of single CRP determination. CONCLUSIONS: IBD was associated with enhanced formation of AOPP, which differed between C and UC with respect to the relationship between rAOPP and disease activity, inflammatory and antioxidant response. These differences may reflect divergent ways that oxidative stress develops in CD and UC. The diagnostic power of rAOPP was insufficient for its clinical application.


Assuntos
Biomarcadores/sangue , Proteínas Sanguíneas/metabolismo , Doenças Inflamatórias Intestinais/sangue , Estresse Oxidativo/fisiologia , Adolescente , Adulto , Idoso , Proteína C-Reativa/análise , Colite Ulcerativa/sangue , Doença de Crohn/sangue , Feminino , Humanos , Inflamação/sangue , Doenças Inflamatórias Intestinais/diagnóstico , Interleucina-6/sangue , Lipídeos/sangue , Masculino , Desnutrição/sangue , Pessoa de Meia-Idade , Oxirredução , Curva ROC , Transferrina/análise
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