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1.
Resour Conserv Recycl ; 164: 105205, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33390661

RESUMO

Understanding the complex relationships amongst Water, Energy, Food and Ecosystems (WEFE nexus) together with the achievement of Sustainable Development Goals (SDGs) is critical for the development of a sustainable and secure future in the Mediterranean area. In this study, we analysed 29 case studies across the Mediterranean region which describe potential success stories for the implementation of good nexus practices. We developed an analytical framework for investigating the impacts on 15 SDG targets and we also explicitly quantified the magnitude of interconnection of nexus pillars with SDGs. Our findings showed that renewable energies have a predominant role on sustainability. Moreover, to achieve the highest positive impacts on economy, environment and society, it is necessary to ensure that both people and ecosystems benefit from a minimum amount of goods/qualities as expected by specific targets like SDG 6.1-4 (clean water and sanitation) and 15.1-3 (life on land), as well as 7.2-3 (affordable and clean energy) that are strongly linked with 13.1 (climate action). We showed also that the strongest interconections between SDG and WEFE are present for the categories of renewable energy system (RED and REW). However, the analysis showed that there is a tendency to focus on a specific sector (e.g. agriculture) and that the good nexus practices implementation is not enough to understand the achievement and progress towards the SDGs. For that reason, we recommended that a more holistic nexus approach including end of supply chain options should be systematically integrated into the project design or evaluation.

2.
Am J Physiol Heart Circ Physiol ; 298(3): H1088-95, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20061537

RESUMO

Variations in circadian rhythms are evident in the incidence of cardiovascular disease, and the risk of cardiovascular events increases when rhythms are disrupted. The suprachiasmatic nucleus is the central circadian pacemaker that regulates the daily rhythm of peripheral organs. Diurnal rhythms have more recently been shown to exist in myocardial tissue and are involved in metabolism and contractile function. Thus we sought to determine whether the functional deletion of the circadian rhythm mouse periodic gene 2 (mPer2) would protect the heart against ischemic injury. Nonreperfused myocardial infarction was induced in anesthetized, ventilated C57 (n = 17) and mPer2 mutant (mPer2-M; n = 15) mice via permanent ligation of the left anterior descending coronary artery. At 4 days post-myocardial infarction, we observed a 43% reduction of infarct area in mPer2-M mice compared with wild-type mice. This is coincident with 25% less macrophage infiltration, 43% higher capillary density, 17% increase in hypertrophy, and 15% less cardiomyocyte apoptosis in the infarct zone. Also, matrix metalloproteinase-9 was expressed in inflammatory cells in both groups, but total protein was 40% higher in wild-type mice, whereas it was not elevated in mPer2-M mice in response to injury. The functional deletion of the mPer2 gene reduces the severity of myocardial infarct injury by limiting the inflammatory response, reducing apoptosis, and inducing cardiomyocyte hypertrophy, thus preserving cardiac function. These findings collectively imply that the disruption of the circadian clock gene mPer2 is protective. Understanding the interactions between circadian rhythm genes and cardiovascular disease may provide insights into potential preventative and therapeutic strategies for susceptible populations.


Assuntos
Deleção de Genes , Infarto do Miocárdio/genética , Infarto do Miocárdio/prevenção & controle , Proteínas Circadianas Period/genética , Animais , Apoptose , Vasos Coronários/fisiopatologia , Modelos Animais de Doenças , Hipertrofia , Ligadura/efeitos adversos , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Infarto do Miocárdio/etiologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia
3.
Biochemistry ; 48(3): 645-56, 2009 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-19119849

RESUMO

Specific proteins with reactive thiol(ate) groups are susceptible to nitric oxide (NO) modification, which can result in S-nitrosation, S-thiolation, or disulfide bond formation. In the present study the effect of NO modification on the functionality of human mitochondrial and cytosolic branched-chain aminotransferases (hBCATm and hBCATc, respectively) was investigated. Here, the NO reactive agents, S-nitrosoglutathione (GSNO), S-nitroso-N-acetyl-dl-penacillamine, and sodium nitroprusside, inactivated both isoforms in a dose-dependent manner. Furthermore, low concentrations of GSNO caused a time-dependent loss in BCAT activity (50 +/- 3% and 77 +/- 2% for hBCATc and hBCATm, respectively) correlating with the loss of four and one to two thiol groups, respectively, confirming the thiols as targets for NO modification. Analysis of GSNO-modified hBCATc by quadrupole time-of-flight mass spectrometry identified a major peak containing three NO adducts and a minor peak equivalent to two NO adducts and one glutathione (GSH) molecule, the latter confirmed by Western blot analysis. Moreover, prolonged exposure or increased levels of GSNO caused increased S-glutathionylation and partial dimerization of hBCATc, suggesting a possible shift from regulation by NO to one of adaptation during nitrosated stress. Although GSNO inactivated hBCATm, neither S-nitrosation, S-glutathionylation, nor dimerization could be detected, suggesting differential mechanisms of regulation through NO between isoforms in the mitochondria and cytosol. Reversal of GSNO-modified hBCAT using GSH alone was only partial, and complete reactivation was only possible using the glutaredoxin/GSH system (97 +/- 4% and 91 +/- 3% for hBCATc and hBCATm, respectively), implicating the importance of a full physiological redox system for activation/inactivation. To conclude, these results clearly demonstrate distinct functional/mechanistic responses to GSNO modification between BCAT isoforms and offer intriguing comparisons between the BCAT proteins and the respective cytosolic and mitochondrial hTrx and hGrx proteins.


Assuntos
Citosol/enzimologia , Mitocôndrias/enzimologia , Proteínas da Gravidez/metabolismo , S-Nitrosoglutationa/farmacologia , Transaminases/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Cisteína/metabolismo , Citosol/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glutarredoxinas/metabolismo , Glutationa Redutase/metabolismo , Humanos , Antígenos de Histocompatibilidade Menor , Mitocôndrias/efeitos dos fármacos , Modelos Biológicos , Dados de Sequência Molecular , Nitroprussiato/farmacologia , Nitrosação/efeitos dos fármacos , Proteínas da Gravidez/antagonistas & inibidores , Proteínas da Gravidez/química , Fatores de Tempo , Transaminases/antagonistas & inibidores , Transaminases/química
4.
Diabetes ; 65(11): 3429-3439, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27495224

RESUMO

Low-avidity autoreactive CD8 T cells (CTLs) escape from thymic negative selection, and peripheral tolerance mechanisms are essential for their regulation. We report the role of proinsulin (PI) expression on the development and activation of insulin-specific CTLs in the NOD mouse model of type 1 diabetes. We studied insulin B-chain-specific CTL from different T-cell receptor transgenic mice (G9Cα-/-) expressing normal PI1 and PI2 or altered PI expression levels. In the absence of PI2 (Ins2-/-), CTL in pancreatic lymph nodes (PLNs) were more activated, and male G9Cα-/- mice developed T1D. Furthermore, when the insulin-specific CTLs developed in transgenic mice lacking their specific PI epitope, the CTLs demonstrated increased cytotoxicity and proliferation in vitro and in vivo in the PLNs after adoptive transfer into NOD recipients. Dendritic cell-stimulated proliferation of insulin-specific T cells was reduced in the presence of lymph node stromal cells (LNSCs) from NOD mice but not from mice lacking the PI epitope. Our study shows that LNSCs regulate CTL activation and suggests that exposure to PI in the periphery is very important in maintenance of tolerance of autoreactive T cells. This is relevant for human type 1 diabetes and has implications for the use of antigen-specific therapy in tolerance induction.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Proinsulina/metabolismo , Animais , Proliferação de Células/genética , Proliferação de Células/fisiologia , Diabetes Mellitus Tipo 1/imunologia , Epitopos/genética , Feminino , Citometria de Fluxo , Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos Transgênicos
5.
J Immunol Methods ; 362(1-2): 199-203, 2010 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-20833177

RESUMO

Insulin autoantibodies (IAA) are usually the first risk-markers detected during the type 1 diabetes prodrome, but precise measurement is difficult as insulin binding is often low. Non-specific binding (NSB) of (125)I-labelled insulin necessitates competitive displacement with unlabelled insulin to demonstrate specificity. NSB varies with different batches of label, suggesting that it is caused by impurities in the label. Addition of bovine serum albumin (BSA) can reduce NSB, so we investigated whether BSA antibodies cause lack of specificity in IAA assays. Samples from patients with newly-diagnosed type 1 diabetes, healthy schoolchildren previously found to have raised (125)I-insulin binding (≥ 0.4 units) and IAA-negative schoolchildren were re-assayed for IAA by radiobinding microassay using commercial (125)I-insulin with and without 1g/dl BSA added to the buffer. Of 100 patients, 68 were IAA-positive on re-assay with BSA compared to 72 without BSA (p=0.125). Of 154 schoolchildren who previously had raised (125)I-insulin binding, only 45 had (125)I-insulin binding ≥ 0.4 units on re-assay with BSA compared to 90 without BSA (p<0.001). Following competitive displacement with unlabelled insulin, 40 were IAA-positive with BSA compared to 48 without BSA (p=0.02). No IAA-negative schoolchildren were IAA-positive on re-assay. Levels of NSB were associated with antibodies binding (125)I-BSA and purification of labelled insulin reduced NSB. Addition of BSA to assay buffer improves the screening efficiency of the IAA assay without reducing disease sensitivity in patients. High titre BSA antibodies interfere with IAA measurement because of (125)I-BSA present in some insulin labels. Improved purification of insulin labels should obviate the need for competitive displacement.


Assuntos
Autoanticorpos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Insulina/imunologia , Soroalbumina Bovina/imunologia , Adolescente , Adulto , Animais , Autoanticorpos/sangue , Bovinos , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Humanos , Lactente , Masculino , Radioimunoensaio , Soroalbumina Bovina/química
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