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1.
Philos Trans A Math Phys Eng Sci ; 382(2268): 20230002, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38281714

RESUMO

We develop an approach to combining contextuality with causality, which is general enough to cover causal background structure, adaptive measurement-based quantum computation and causal networks. The key idea is to view contextuality as arising from a game played between Experimenter and Nature, allowing for causal dependencies in the actions of both the Experimenter (choice of measurements) and Nature (choice of outcomes). This article is part of the theme issue 'Quantum contextuality, causality and freedom of choice'.

2.
Nat Commun ; 13(1): 7445, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36460651

RESUMO

Theoretical research into many-body quantum systems has mostly focused on regular structures which have a small, simple unit cell and where a vanishingly small fraction of the pairs of the constituents directly interact. Motivated by advances in control over the pairwise interactions in many-body simulators, we determine the fate of spin systems on more general, arbitrary graphs. Placing the minimum possible constraints on the underlying graph, we prove how, with certainty in the thermodynamic limit, such systems behave like a single collective spin. We thus understand the emergence of complex many-body physics as dependent on 'exceptional', geometrically constrained structures such as the low-dimensional, regular ones found in nature. Within the space of dense graphs we identify hitherto unknown exceptions via their inhomogeneity and observe how complexity is heralded in these systems by entanglement and highly non-uniform correlation functions. Our work paves the way for the discovery and exploitation of a whole class of geometries which can host uniquely complex phases of matter.

3.
Thromb Haemost ; 122(2): 196-207, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34619795

RESUMO

BACKGROUND: 3F7 is a monoclonal antibody targeting the enzymatic pocket of activated factor XII (FXIIa), thereby inhibiting its catalytic activity. Given the emerging role of FXIIa in promoting thromboinflammation, along with its apparent redundancy for hemostasis, the selective inhibition of FXIIa represents a novel and highly attractive approach targeting pathogenic processes that cause thromboinflammation-driven cardiovascular diseases. METHODS: The effects of FXIIa inhibition were investigated using three distinct mouse models of cardiovascular disease-angiotensin II-induced abdominal aortic aneurysm (AAA), an ApoE-/- model of atherosclerosis, and a tandem stenosis model of atherosclerotic plaque instability. 3F7 or its isotype control, BM4, was administered to mice (10 mg/kg) on alternate days for 4 to 8 weeks, depending on the experimental model. Mice were examined for the development and size of AAAs, or the burden and instability of atherosclerosis and associated markers of inflammation. RESULTS: Inhibition of FXIIa resulted in a reduced incidence of larger AAAs, with less acute aortic ruptures and an associated fibro-protective phenotype. FXIIa inhibition also decreased stable atherosclerotic plaque burden and achieved plaque stabilization associated with increased deposition of fibrous structures, a >2-fold thicker fibrous cap, increased cap-to-core ratio, and reduction in localized and systemic inflammatory markers. CONCLUSION: Inhibition of FXIIa attenuates disease severity across three mouse models of thromboinflammation-driven cardiovascular diseases. Specifically, the FXIIa-inhibiting monoclonal antibody 3F7 reduces AAA severity, inhibits the development of atherosclerosis, and stabilizes vulnerable plaques. Ultimately, clinical trials in patients with cardiovascular diseases such as AAA and atherosclerosis are warranted to demonstrate the therapeutic potential of FXIIa inhibition.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Aneurisma da Aorta Abdominal/prevenção & controle , Aterosclerose/prevenção & controle , Fator XIIa/antagonistas & inibidores , Placa Aterosclerótica/metabolismo , Animais , Aneurisma da Aorta Abdominal/epidemiologia , Apolipoproteínas E , Modelos Animais de Doenças , Inflamação , Masculino , Camundongos
4.
Pharmaceutics ; 13(9)2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34575580

RESUMO

Medical devices directly exposed to blood are commonly used to treat cardiovascular diseases. However, these devices are associated with inflammatory reactions leading to delayed healing, rejection of foreign material or device-associated thrombus formation. We developed a novel recombinant fusion protein as a new biocompatible coating strategy for medical devices with direct blood contact. We genetically fused human serum albumin (HSA) with ectonucleoside triphosphate diphosphohydrolase-1 (CD39), a promising anti-thrombotic and anti-inflammatory drug candidate. The HSA-CD39 fusion protein is highly functional in degrading ATP and ADP, major pro-inflammatory reagents and platelet agonists. Their enzymatic properties result in the generation of AMP, which is further degraded by CD73 to adenosine, an anti-inflammatory and anti-platelet reagent. HSA-CD39 is functional after lyophilisation, coating and storage of coated materials for up to 8 weeks. HSA-CD39 coating shows promising and stable functionality even after sterilisation and does not hinder endothelialisation of primary human endothelial cells. It shows a high level of haemocompatibility and diminished blood cell adhesion when coated on nitinol stents or polyvinylchloride tubes. In conclusion, we developed a new recombinant fusion protein combining HSA and CD39, and demonstrated that it has potential to reduce thrombotic and inflammatory complications often associated with medical devices directly exposed to blood.

6.
Redox Biol ; 24: 101166, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30897408

RESUMO

The plant Garcinia kola is used in African ethno-medicine to treat various oxidation- and inflammation-related diseases but its bioactive compounds are not well characterized. Garcinoic acid (GA) is one of the few phytochemicals that have been isolated from Garcinia kola. We investigated the anti-inflammatory potential of the methanol extract of Garcinia kola seeds (NE) and purified GA, as a major phytochemical in these seeds, in lipopolysaccharide (LPS)-activated mouse RAW264.7 macrophages and its anti-atherosclerotic potential in high fat diet fed ApoE-/- mice. This study outlines an optimized procedure for the extraction and purification of GA from Garcinia kola seeds with an increased yield and a purity of >99%. We found that LPS-induced upregulation of iNos and Cox2 expression, and the formation of the respective signaling molecules nitric oxide and prostanoids, were significantly diminished by both the NE and GA. In addition, GA treatment in mice decreased intra-plaque inflammation by attenuating nitrotyrosinylation. Further, modulation of lymphocyte sub-populations in blood and spleen have been detected, showing immune regulative properties of GA. Our study provides molecular insights into the anti-inflammatory activities of Garcinia kola and reveals GA as promising natural lead for the development of multi-target drugs to treat inflammation-driven diseases.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Benzopiranos/farmacologia , Garcinia kola/química , Nozes/química , Vitamina E/análogos & derivados , Vitamina E/farmacologia , Animais , Biomarcadores , Cromatografia Líquida , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células RAW 264.7 , Sementes , Transdução de Sinais , Espectrometria de Massas em Tandem
7.
Eur Heart J ; 39(35): 3301-3310, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30219874

RESUMO

Aims: As the inflammatory enzyme myeloperoxidase (MPO) is abundant in ruptured human atherosclerotic plaques, we aimed to investigate the role of MPO as a potential diagnostic and therapeutic target for high-risk plaque. Methods and results: We employed the tandem stenosis model of atherosclerotic plaque instability in apolipoprotein E gene knockout (Apoe-/-) mice. To test the role of MPO, we used Mpo-/-Apoe-/- mice and the 2-thioxanthine MPO inhibitor AZM198. In vivo MPO activity was assessed by liquid chromatography-tandem mass spectrometry detection of 2-chloroethidium generation from hydroethidine and by bis-5HT-DTPA-Gd (MPO-Gd) molecular magnetic resonance imaging (MRI), while plaque phenotype was verified histologically. Myeloperoxidase activity was two-fold greater in plaque with unstable compared with stable phenotype. Genetic deletion of MPO significantly increased fibrous cap thickness, and decreased plaque fibrin and haemosiderin content in plaque with unstable phenotype. AZM198 inhibited MPO activity and it also increased fibrous cap thickness and decreased fibrin and haemosiderin in plaque with unstable phenotype, without affecting lesion monocytes and red blood cell markers or circulating leukocytes and lipids. MPO-Gd MRI demonstrated sustained enhancement of plaque with unstable phenotype on T1-weighted imaging that was two-fold greater than stable plaque and was significantly attenuated by both AZM198 treatment and deletion of the Mpo gene. Conclusion: Our data implicate MPO in atherosclerotic plaque instability and suggest that non-invasive imaging and pharmacological inhibition of plaque MPO activity hold promise for clinical translation in the management of high-risk coronary artery disease.


Assuntos
Aterosclerose/diagnóstico por imagem , Aterosclerose/enzimologia , Imageamento por Ressonância Magnética/métodos , Imagem Molecular , Peroxidase/metabolismo , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/enzimologia , Animais , Modelos Animais de Doenças , Fibrina/metabolismo , Hemossiderina/metabolismo , Espectrometria de Massas , Camundongos Knockout , Peroxidase/antagonistas & inibidores , Tioxantenos/farmacologia
8.
JCI Insight ; 3(15)2018 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-30089712

RESUMO

Despite advances in antithrombotic therapy, the risk of recurrent coronary/cerebrovascular ischemia or venous thromboembolism remains high. Dual pathway antithrombotic blockade, using both antiplatelet and anticoagulant therapy, offers the promise of improved thrombotic protection; however, widespread adoption remains tempered by substantial risk of major bleeding. Here, we report a dual pathway therapeutic capable of site-specific targeting to activated platelets and therapeutic enrichment at the site of thrombus growth to allow reduced dosing without compromised antithrombotic efficacy. We engineered a recombinant fusion protein, SCE5-TAP, which consists of a single-chain antibody (SCE5) that targets and blocks the activated GPIIb/IIIa complex, and tick anticoagulant peptide (TAP), a potent direct inhibitor of activated factor X (FXa). SCE5-TAP demonstrated selective platelet targeting and inhibition of thrombosis in murine models of both carotid artery and inferior vena cava thrombosis, without a significant impact on hemostasis. Selective targeting to activated platelets provides an attractive strategy to achieve high antithrombotic efficacy with reduced risk of bleeding complications.


Assuntos
Plaquetas/efeitos dos fármacos , Inibidores do Fator Xa/administração & dosagem , Hemostasia/efeitos dos fármacos , Trombose/prevenção & controle , Animais , Proteínas de Artrópodes/administração & dosagem , Proteínas de Artrópodes/genética , Modelos Animais de Doenças , Voluntários Saudáveis , Humanos , Imunoconjugados/administração & dosagem , Imunoconjugados/genética , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos , Ativação Plaquetária/efeitos dos fármacos , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Anticorpos de Cadeia Única/administração & dosagem , Anticorpos de Cadeia Única/genética , Trombose/etiologia
9.
Mol Ther ; 26(4): 1056-1065, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29525742

RESUMO

Abdominal aortic aneurysm (AAA) is an often deadly disease without medical, non-invasive treatment options. The upregulation of vascular cell adhesion molecule-1 (VCAM-1) on aortic endothelium provides an early target epitope for a novel biotechnological theranostic approach. MicroRNA-126 was used as a therapeutic agent, based on its capability to downregulate VCAM-1 expression in endothelial cells and thereby reduces leukocyte adhesion and exerts anti-inflammatory effects. Ultrasound microbubbles were chosen as carriers, allowing both molecular imaging as well as targeted therapy of AAA. Microbubbles were coupled with a VCAM-1-targeted single-chain antibody (scFvmVCAM-1) and a microRNA-126 mimic (M126) constituting theranostic microbubbles (TargMB-M126). TargMB-M126 downregulates VCAM-1 expression in vitro and in an in vivo acute inflammatory murine model. Most importantly, using TargMB-M126 and ultrasound-guided burst delivery of M126, the development of AAA in an angiotensin-II-induced mouse model can be prevented. Overall, we describe a unique biotechnological theranostic approach with the potential for early diagnosis and long-sought-after medical therapy of AAA.


Assuntos
Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/patologia , Terapia Genética , MicroRNAs/genética , Animais , Aneurisma da Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/terapia , Biomarcadores , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais , Técnicas de Transferência de Genes , Terapia Genética/métodos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Knockout , MicroRNAs/administração & dosagem , MicroRNAs/química , Imagem Molecular , Anticorpos de Cadeia Única/farmacologia , Ultrassonografia , Molécula 1 de Adesão de Célula Vascular/antagonistas & inibidores , Molécula 1 de Adesão de Célula Vascular/química , Molécula 1 de Adesão de Célula Vascular/metabolismo
10.
Eur Heart J ; 39(2): 111-116, 2018 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-28472483

RESUMO

Aims: CD39 is a cell membrane NTPase with anti-inflammatory and anti-platelet effects. However, its clinical use is limited by its bleeding side effect. With the goal of harnessing its therapeutic potential while avoiding haemostatic problems, we designed a fusion protein consisting of the extracellular domain of CD39 and a single-chain antibody (Targ-CD39) that specifically binds to activated glycoprotein (GP)IIb/IIIa and thus to activated platelets. Through this enrichment at activated platelets, the required systemic dose is below the dose impairing haemostasis. Methods and results: Using an ischaemia/reperfusion mouse model (left anterior descending artery ligated for 1 h) we achieved remarkable protection of the reperfused tissue with Targ-CD39 compared with Non-targ-CD39 (mutated, non-binding version of Targ-CD39) and PBS control. Targ-CD39 restored ejection fraction and fractional shortening to a level indistinguishable from pre-injury status, while controls showed functional deterioration. Employing advanced clinically relevant methods of ultrasound analysis, we observed that both radial and longitudinal strain and strain rate showed infarct-typical changes of myocardial deformation in controls, but not in Targ-CD39 treated mice. Histological assessment confirmed strong reduction of infarct size and increase in neovascularization. Furthermore, attenuation of post-ischaemic inflammation was seen in cytokine profiling. Conclusion: Overall, we demonstrate that Targ-CD39 holds promise for treatment of myocardial infarction.


Assuntos
Adenosina Trifosfatases/uso terapêutico , Anticorpos/uso terapêutico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Proteínas Recombinantes de Fusão/uso terapêutico , Adenosina Trifosfatases/farmacologia , Animais , Anticorpos/farmacologia , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Contração Miocárdica/efeitos dos fármacos , Infarto do Miocárdio/sangue , Infarto do Miocárdio/patologia , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/sangue , Traumatismo por Reperfusão Miocárdica/patologia , Ativação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Transporte Proteico , Proteínas Recombinantes de Fusão/farmacologia
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