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2.
BMC Cardiovasc Disord ; 23(1): 232, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-37138228

RESUMO

BACKGROUND: ST-segment elevation myocardial infarction (STEMI) still causes significant mortality and morbidity despite best-practice revascularization and adjunct medical strategies. Within the STEMI population, there is a spectrum of higher and lower risk patients with respect to major adverse cardiovascular and cerebral events (MACCE) or re-hospitalization due to heart failure. Myocardial and systemic metabolic disorders modulate patient risk in STEMI. Systematic cardiocirculatory and metabolic phenotyping to assess the bidirectional interaction of cardiac and systemic metabolism in myocardial ischemia is lacking. METHODS: Systemic organ communication in STEMI (SYSTEMI) is an all-comer open-end prospective study in STEMI patients > 18 years of age to assess the interaction of cardiac and systemic metabolism in STEMI by systematically collecting data on a regional and systemic level. Primary endpoint will be myocardial function, left ventricular remodelling, myocardial texture and coronary patency at 6 month after STEMI. Secondary endpoint will be all-cause death, MACCE, and re-hospitalisation due to heart failure or revascularisation assessed 12 month after STEMI. The objective of SYSTEMI is to identify metabolic systemic and myocardial master switches that determine primary and secondary endpoints. In SYSTEMI 150-200 patients are expected to be recruited per year. Patient data will be collected at the index event, within 24 h, 5 days as well as 6 and 12 months after STEMI. Data acquisition will be performed in multilayer approaches. Myocardial function will be assessed by using serial cardiac imaging with cineventriculography, echocardiography and cardiovascular magnetic resonance. Myocardial metabolism will be analysed by multi-nuclei magnetic resonance spectroscopy. Systemic metabolism will be approached by serial liquid biopsies and analysed with respect to glucose and lipid metabolism as well as oxygen transport. In summary, SYSTEMI enables a comprehensive data analysis on the levels of organ structure and function alongside hemodynamic, genomic and transcriptomic information to assess cardiac and systemic metabolism. DISCUSSION: SYSTEMI aims to identify novel metabolic patterns and master-switches in the interaction of cardiac and systemic metabolism to improve diagnostic and therapeutic algorithms in myocardial ischemia for patient-risk assessment and tailored therapy. TRIAL REGISTRATION: Trial Registration Number: NCT03539133.


Assuntos
Doença da Artéria Coronariana , Insuficiência Cardíaca , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Estudos de Coortes , Estudos Prospectivos , Intervenção Coronária Percutânea/efeitos adversos , Doença da Artéria Coronariana/complicações , Insuficiência Cardíaca/etiologia , Resultado do Tratamento
3.
J Prosthet Dent ; 129(6): 939-945, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34598769

RESUMO

STATEMENT OF PROBLEM: Occlusal devices can be either conventionally processed, milled, or printed. However, little is known about the biocompatibility of 3D printing resin materials. PURPOSE: The purpose of this in vitro study was to compare the viability and morphology of human gingival fibroblast cells (HFG-1) after cultivation on conventionally processed, milled, and printed occlusal device materials with different surface treatments. MATERIAL AND METHODS: Disks of a conventionally processed (PalaXpress Clear [pP]), milled (Yamahachi PMMA Clear [sY]), and 2 different printed materials (Dental LT Clear Resin [aD]; Freeprint splint [aF]) were prepared. The surfaces of the specimens were finished by using 2 different treatments (unpolished and polished with P1200-grit silicon carbide paper). HGF-1 cells were cultivated on the specimens for 24 hours, and a viability assay was performed by using polystyrene disks as a control (n=9 disks per group). Cell morphology and the topography of the specimens were examined with scanning electron microscopy (n=3 disks per group). Two-way analysis of variance was applied to determine the effect of material and surface treatment followed by the post hoc Fisher least significant difference test (α=.05). RESULTS: Overall, material (P<.001) and surface treatment (P<.001) significantly influenced the viability of HGF-1 cells. The viability of cells on all specimens displayed mean values between 0.85 and 1.01 compared with the control except for unpolished aD (0.00 ±0.07) and aF (0.02 ±0.05) that had only a few cells with a round shape. CONCLUSIONS: The behavior of HGF-1 cells on conventionally processed and milled specimens was similar and not dependent on the surface treatment. Unpolished printed specimens had a cytotoxic effect. However, after polishing, cell behavior was similar to that of the conventionally processed and milled specimens.


Assuntos
Materiais Dentários , Impressão Tridimensional , Humanos , Teste de Materiais , Fibroblastos , Propriedades de Superfície
4.
Basic Res Cardiol ; 117(1): 48, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36205817

RESUMO

Although p38 MAP Kinase α (p38 MAPKα) is generally accepted to play a central role in the cardiac stress response, to date its function in maladaptive cardiac hypertrophy is still not unambiguously defined. To induce a pathological type of cardiac hypertrophy we infused angiotensin II (AngII) for 2 days via osmotic mini pumps in control and tamoxifen-inducible, cardiomyocyte (CM)-specific p38 MAPKα KO mice (iCMp38αKO) and assessed cardiac function by echocardiography, complemented by transcriptomic, histological, and immune cell analysis. AngII treatment after inactivation of p38 MAPKα in CM results in left ventricular (LV) dilatation within 48 h (EDV: BL: 83.8 ± 22.5 µl, 48 h AngII: 109.7 ± 14.6 µl) and an ectopic lipid deposition in cardiomyocytes, reflecting a metabolic dysfunction in pressure overload (PO). This was accompanied by a concerted downregulation of transcripts for oxidative phosphorylation, TCA cycle, and fatty acid metabolism. Cardiac inflammation involving neutrophils, macrophages, B- and T-cells was significantly enhanced. Inhibition of adipose tissue lipolysis by the small molecule inhibitor of adipocytetriglyceride lipase (ATGL) Atglistatin reduced cardiac lipid accumulation by 70% and neutrophil infiltration by 30% and went along with an improved cardiac function. Direct targeting of neutrophils by means of anti Ly6G-antibody administration in vivo led to a reduced LV dilation in iCMp38αKO mice and an improved systolic function (EF: 39.27 ± 14%). Thus, adipose tissue lipolysis and CM lipid accumulation augmented cardiac inflammation in iCMp38αKO mice. Neutrophils, in particular, triggered the rapid left ventricular dilatation. We provide the first evidence that p38 MAPKα acts as an essential switch in cardiac adaptation to PO by mitigating metabolic dysfunction and inflammation. Moreover, we identified a heart-adipose tissue-immune cell crosstalk, which might serve as new therapeutic target in cardiac pathologies.


Assuntos
Insuficiência Cardíaca , Miócitos Cardíacos , Tecido Adiposo/metabolismo , Angiotensina II/metabolismo , Animais , Cardiomegalia/metabolismo , Ácidos Graxos/metabolismo , Inflamação/metabolismo , Lipase/metabolismo , Lipase/uso terapêutico , Lipídeos/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Neutrófilos/metabolismo , Tamoxifeno/metabolismo , Tamoxifeno/uso terapêutico , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/uso terapêutico
5.
Arterioscler Thromb Vasc Biol ; 41(10): 2551-2562, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34380333

RESUMO

Objective: The dominant driver of arteriogenesis is elevated shear stress sensed by the endothelial glycocalyx thereby promoting arterial outward remodeling. Hyaluronan, a critical component of the endothelial glycocalyx, is synthesized by 3 HAS isoenzymes (hyaluronan synthases 1-3) at the plasma membrane. Considering further the importance of HAS3 for smooth muscle cell and immune cell functions we aimed to evaluate its role in collateral artery growth. Approach and Results: Male Has3-deficient (Has3-KO) mice were subjected to hindlimb ischemia. Blood perfusion was monitored by laser Doppler perfusion imaging and endothelial function was assessed by measurement of flow-mediated dilation in vivo. Collateral remodeling was monitored by high resolution magnetic resonance angiography. A neutralizing antibody against CD44 (clone KM201) was injected intraperitoneally to analyze hyaluronan signaling in vivo. After hindlimb ischemia, Has3-KO mice showed a reduced arteriogenic response with decreased collateral remodeling and impaired perfusion recovery. While postischemic leukocyte infiltration was unaffected, a diminished flow-mediated dilation pointed towards an impaired endothelial cell function. Indeed, endothelial AKT (protein kinase B)-dependent eNOS (endothelial nitric oxide synthase) phosphorylation at Ser1177 was substantially reduced in Has3-KO thigh muscles. Endothelial-specific Has3-KO mice mimicked the hindlimb ischemia-induced phenotype of impaired perfusion recovery as observed in global Has3-deficiency. Mechanistically, blocking selectively the hyaluronan binding site of CD44 reduced flow-mediated dilation, thereby suggesting hyaluronan signaling through CD44 as the underlying signaling pathway. Conclusions: In summary, HAS3 contributes to arteriogenesis in hindlimb ischemia by hyaluronan/CD44-mediated stimulation of eNOS phosphorylation at Ser1177. Thus, strategies augmenting endothelial HAS3 or CD44 could be envisioned to enhance vascularization under pathological conditions.


Assuntos
Células Endoteliais/enzimologia , Membro Posterior/irrigação sanguínea , Receptores de Hialuronatos/metabolismo , Hialuronan Sintases/metabolismo , Isquemia/enzimologia , Neovascularização Fisiológica , Óxido Nítrico Sintase Tipo III/metabolismo , Animais , Circulação Colateral , Modelos Animais de Doenças , Humanos , Hialuronan Sintases/genética , Isquemia/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Óxido Nítrico Sintase Tipo III/genética , Fosforilação , Fluxo Sanguíneo Regional , Transdução de Sinais , Fatores de Tempo
6.
Arterioscler Thromb Vasc Biol ; 41(2): 796-807, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33380173

RESUMO

OBJECTIVE: The aim of this study was to unravel mechanisms whereby deficiency of the transcription factor Id3 (inhibitor of differentiation 3) leads to metabolic dysfunction in visceral obesity. We investigated the impact of loss of Id3 on hyaluronic acid (HA) production by the 3 HAS isoenzymes (HA synthases; -1, -2, and -3) and on obesity-induced adipose tissue (AT) accumulation of proinflammatory B cells. Approach and Results: Male Id3-/- mice and respective wild-type littermate controls were fed a 60% high-fat diet for 4 weeks. An increase in inflammatory B2 cells was detected in Id3-/- epididymal AT. HA accumulated in epididymal AT of high-fat diet-fed Id3-/- mice and circulating levels of HA were elevated. Has2 mRNA expression was increased in epididymal AT of Id3-/- mice. Luciferase promoter assays showed that Id3 suppressed Has2 promoter activity, while loss of Id3 stimulated Has2 promoter activity. Functionally, HA strongly promoted B2 cell adhesion in the AT and on cultured vascular smooth muscle cells of Id3-/- mice, an effect sensitive to hyaluronidase. CONCLUSIONS: Our data demonstrate that loss of Id3 increases Has2 expression in the epididymal AT, thereby promoting HA accumulation. In turn, elevated HA content promotes HA-dependent binding of B2 cells and an increase in the B2 cells in the AT, which contributes to AT inflammation.


Assuntos
Tecido Adiposo/metabolismo , Linfócitos B/metabolismo , Hialuronan Sintases/metabolismo , Ácido Hialurônico/biossíntese , Proteínas Inibidoras de Diferenciação/metabolismo , Paniculite/metabolismo , Tecido Adiposo/imunologia , Animais , Linfócitos B/imunologia , Adesão Celular , Células Cultivadas , Técnicas de Cocultura , Dieta Hiperlipídica , Modelos Animais de Doenças , Hialuronan Sintases/genética , Proteínas Inibidoras de Diferenciação/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/imunologia , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/imunologia , Miócitos de Músculo Liso/metabolismo , Paniculite/genética , Paniculite/imunologia , Fenótipo , Transdução de Sinais , Regulação para Cima
7.
Clin Oral Implants Res ; 33(4): 424-432, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35137461

RESUMO

OBJECTIVES: To determine whether the surface treatment of zirconia affects biofilm formation in an in vitro three-species biofilm model and in situ. MATERIAL AND METHODS: Zirconia surfaces considered for the transmucosal portion of a zirconia implant were compared with polished pure titanium grade 4 (Tp). Disks 13 mm in diameter of either polished (Zp), polished and heat-treated (Zpt), machined (Zm), machined and heat-treated (Zmt) and sandblasted, etched and heat-treated (Z14) zirconia were fabricated. Surface roughness and wettability of specimens was measured. Biofilm formation was evaluated by safranin staining and scanning electron microscopy (SEM) using a three-species model, and intraorally with 16 volunteers carrying oral splints in two independent experiments. Relative biofilm formation was compared with Kruskal-Wallis followed by Bonferroni post hoc test (α = 0.05). RESULTS: In vitro biofilm formation with optical density values on Zp (0.14 ± 0.01), Zpt (0.14 ± 0.02), Zm (0.13 ± 0.01) and Zmt (0.13 ± 0.01) was significantly lower than on Tp (0.21 ± 0.05) and Z14 (0.20 ± 0.04) (p < .05). In situ biofilm formation was significantly higher on Z14 (0.56 ± 0.45) (p < .05), while no significant differences in optical density were observed among Zp (0.25 ± 0.20), Zm (0.36 ± 0.34) and Tp (0.28 ± 0.22). SEM analysis supported quantitative findings. CONCLUSIONS: In the in vitro, three-species biofilm model differences in material and surface roughness affected biofilm formation. In situ biofilm formation was mainly affected by the surface roughness of the specimens. Polishing of zirconia is recommended to reduce biofilm formation, while heat treatment has no significant effect.


Assuntos
Implantes Dentários , Biofilmes , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Titânio , Zircônio
8.
J Mater Sci Mater Med ; 33(8): 61, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35849225

RESUMO

Bone graft materials are applied in patients to augment bone defects and enable the insertion of an implant in its ideal position. However, the currently available augmentation materials do not meet the requirements of being completely resorbed and replaced by new bone within 3 to 6 months. A novel electrospun cotton-wool like material (Bonewool®, Zurich Biomaterials LLC, Zurich, Switzerland) consisting of biodegradable poly(lactic-co-glycolic) acid (PLGA) fibers with incorporated amorphous ß-tricalcium phosphate (ß-TCP) nanoparticles has been compared to a frequently used bovine derived hydroxyapatite (Bio-Oss®, Geistlich Pharma, Wolhusen, Switzerland) in vitro. The material composition was determined and the degradation behavior (calcium release and pH in different solutions) as well as bioactivity has been measured. Degradation behavior of PLGA/ß-TCP was generally more progressive than for Bio-Oss®, indicating that this material is potentially completely resorbable. Graphical abstract.


Assuntos
Substitutos Ósseos , Fosfatos de Cálcio , Animais , Materiais Biocompatíveis/química , Fosfatos de Cálcio/química , Bovinos , Humanos
9.
J Esthet Restor Dent ; 34(5): 833-842, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35305288

RESUMO

OBJECTIVE: The purpose of this study is to compare the bonding performance and mechanical properties of two different resin composite cements using simplified adhesive bonding strategies. MATERIALS AND METHODS: Shear bond strength of two resin composite cements (an adhesive cement: Panavia V5 [PV5] and a self-adhesive cement: RelyX Universal [RUV]) to human enamel, dentin, and a variety of restorative materials (microfilled composite, composite, polymer-infiltrated ceramic, feldspar ceramic, lithium disilicate and zirconia) was measured. Thermocycle aging was performed with selected material combinations. RESULTS: For both cements, the highest shear bond strength to dentin was achieved when using a primer (PV5: 18.0 ± 4.2 MPa, RUV: 18.2 ± 3.3 MPa). Additional etching of dentin reduced bond strength for RUV (12.5 ± 4.9 MPa). On enamel, PV5 achieved the highest bond strength when the primer was used (18.0 ± 3.1 MPa), while for RUV etching of enamel and priming provided best results (21.2 ± 6.6 MPa). Shear bond strength of RUV to restorative materials was superior to PV5. Bonding to resin-based materials was predominantly observed for RUV. CONCLUSIONS: While use of RUV with the selective-etch technique is slightly more labor intensive than PV5, RUV (with its universal primer) displayed a high-bonding potential to all tested restorative materials, especially to resin. CLINICAL SIGNIFICANCE: For a strong adhesion to the tooth substrate, PV5 (with its tooth primer) is to be preferred because etching with phosphoric acid is not required. However, when using a wide range of varying restorative materials, RUV with its universal primer seems to be an adequate option.


Assuntos
Colagem Dentária , Cerâmica , Colagem Dentária/métodos , Cimentos Dentários , Materiais Dentários , Análise do Estresse Dentário , Humanos , Teste de Materiais , Cimentos de Resina/química , Resistência ao Cisalhamento , Propriedades de Superfície
10.
Diabetologia ; 64(8): 1834-1849, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34131781

RESUMO

AIMS/HYPOTHESIS: People with diabetes have an increased cardiovascular risk with an accelerated development of atherosclerosis and an elevated mortality rate after myocardial infarction. Therefore, cardioprotective effects of glucose-lowering therapies are of major importance for the pharmacotherapy of individuals with type 2 diabetes. For sodium-glucose cotransporter 2 inhibitors (SGLT2is), in addition to a reduction in blood glucose, beneficial effects on atherosclerosis, obesity, renal function and blood pressure have been observed. Recent results showed a reduced risk of worsening heart failure and cardiovascular deaths under dapagliflozin treatment irrespective of the diabetic state. However, the underlying mechanisms are yet unknown. Platelets are known drivers of atherosclerosis and atherothrombosis and disturbed platelet activation has also been suggested to occur in type 2 diabetes. Therefore, the present study investigates the impact of the SGLT2i dapagliflozin on the interplay between platelets and inflammation in atherogenesis. METHODS: Male, 8-week-old LDL-receptor-deficient (Ldlr-/-) mice received a high-fat, high-sucrose diabetogenic diet supplemented without (control) or with dapagliflozin (5 mg/kg body weight per day) for two time periods: 8 and 25 weeks. In a first translational approach, eight healthy volunteers received 10 mg dapagliflozin/day for 4 weeks. RESULTS: Dapagliflozin treatment ameliorated atherosclerotic lesion development, reduced circulating platelet-leucocyte aggregates (glycoprotein [GP]Ib+CD45+: 29.40 ± 5.94 vs 17.00 ± 5.69 cells, p < 0.01; GPIb+lymphocyte antigen 6 complex, locus G+ (Ly6G): 8.00 ± 2.45 vs 4.33 ± 1.75 cells, p < 0.05) and decreased aortic macrophage infiltration (1.31 ± 0.62 vs 0.70 ± 0.58 ×103 cells/aorta, p < 0.01). Deeper analysis revealed that dapagliflozin decreased activated CD62P-positive platelets in Ldlr-/- mice fed a diabetogenic diet (3.78 ± 1.20% vs 2.83 ± 1.06%, p < 0.01) without affecting bleeding time (85.29 ± 37.27 vs 89.25 ± 16.26 s, p = 0.78). While blood glucose was only moderately affected, dapagliflozin further reduced endogenous thrombin generation (581.4 ± 194.6 nmol/l × min) × 10-9 thrombin vs 254.1 ± 106.4 (nmol/l × min) × 10-9 thrombin), thereby decreasing one of the most important platelet activators. We observed a direct inhibitory effect of dapagliflozin on isolated platelets. In addition, dapagliflozin increased HDL-cholesterol levels. Importantly, higher HDL-cholesterol levels (1.70 ± 0.58 vs 3.15 ± 1.67 mmol/l, p < 0.01) likely contribute to dapagliflozin-mediated inhibition of platelet activation and thrombin generation. Accordingly, in line with the results in mice, treatment with dapagliflozin lowered CD62P-positive platelet counts in humans after stimulation by collagen-related peptide (CRP; 88.13 ± 5.37% of platelets vs 77.59 ± 10.70%, p < 0.05) or thrombin receptor activator peptide-6 (TRAP-6; 44.23 ± 15.54% vs 28.96 ± 11.41%, p < 0.01) without affecting haemostasis. CONCLUSIONS/INTERPRETATION: We demonstrate that dapagliflozin-mediated atheroprotection in mice is driven by elevated HDL-cholesterol and ameliorated thrombin-platelet-mediated inflammation without interfering with haemostasis. This glucose-independent mechanism likely contributes to dapagliflozin's beneficial cardiovascular risk profile.


Assuntos
Compostos Benzidrílicos/uso terapêutico , Doença da Artéria Coronariana/prevenção & controle , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos/uso terapêutico , Ativação Plaquetária/efeitos dos fármacos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Trombina/metabolismo , Adulto , Animais , Glicemia/metabolismo , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/prevenção & controle , HDL-Colesterol/sangue , Doença da Artéria Coronariana/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Citometria de Fluxo , Voluntários Saudáveis , Humanos , Imuno-Histoquímica , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Selectina-P/metabolismo , Contagem de Plaquetas , Reação em Cadeia da Polimerase em Tempo Real , Comportamento de Redução do Risco
11.
PLoS Biol ; 16(6): e2004408, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29927970

RESUMO

We show that the cyclin-dependent kinase inhibitor 1B (CDKN1B)/p27, previously known as a cell cycle inhibitor, is also localized within mitochondria. The migratory capacity of endothelial cells, which need intact mitochondria, is completely dependent on mitochondrial p27. Mitochondrial p27 improves mitochondrial membrane potential, increases adenosine triphosphate (ATP) content, and is required for the promigratory effect of caffeine. Domain mapping of p27 revealed that the N-terminus and C-terminus are required for those improvements. Further analysis of those regions revealed that the translocation of p27 into the mitochondria and its promigratory activity depend on serine 10 and threonine 187. In addition, mitochondrial p27 protects cardiomyocytes against apoptosis. Moreover, mitochondrial p27 is necessary and sufficient for cardiac myofibroblast differentiation. In addition, p27 deficiency and aging decrease respiration in heart mitochondria. Caffeine does not increase respiration in p27-deficient animals, whereas aged mice display improvement after 10 days of caffeine in drinking water. Moreover, caffeine induces transcriptome changes in a p27-dependent manner, affecting mostly genes relevant for mitochondrial processes. Caffeine also reduces infarct size after myocardial infarction in prediabetic mice and increases mitochondrial p27. Our data characterize mitochondrial p27 as a common denominator that improves mitochondria-dependent processes and define an increase in mitochondrial p27 as a new mode of action of caffeine.


Assuntos
Cafeína/farmacologia , Cardiotônicos/farmacologia , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Mitocôndrias/metabolismo , Infarto do Miocárdio/patologia , Miócitos Cardíacos/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/fisiologia , Diferenciação Celular/fisiologia , Linhagem Celular , Movimento Celular/fisiologia , Inibidor de Quinase Dependente de Ciclina p27/genética , Células Endoteliais/fisiologia , Células HEK293 , Humanos , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/citologia , Transporte Proteico/fisiologia
12.
Circ Res ; 124(10): 1433-1447, 2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-30916618

RESUMO

RATIONALE: Immediate changes in the ECM (extracellular matrix) microenvironment occur after myocardial ischemia and reperfusion (I/R) injury. OBJECTIVE: Aim of this study was to unravel the role of the early hyaluronan (HA)-rich ECM after I/R. METHODS AND RESULTS: Genetic deletion of Has2 and Has1 was used in a murine model of cardiac I/R. Chemical exchange saturation transfer imaging was adapted to image cardiac ECM post-I/R. Of note, the cardiac chemical exchange saturation transfer signal was severely suppressed by Has2 deletion and pharmacological inhibition of HA synthesis 24 hours after I/R. Has2 KO ( Has2 deficient) mice showed impaired hemodynamic function suggesting a protective role for endogenous HA synthesis. In contrast to Has2 deficiency, Has1-deficient mice developed no specific phenotype compared with control post-I/R. Importantly, in Has2 KO mice, cardiac macrophages were diminished after I/R as detected by 19F MRI (magnetic resonance imaging) of perfluorcarbon-labeled immune cells, Mac-2/Galectin-3 immunostaining, and FACS (fluorescence-activated cell sorting) analysis (CD45+CD11b+Ly6G-CD64+F4/80+cells). In contrast to macrophages, cardiac Ly6Chigh and Ly6Clow monocytes were unaffected post-I/R compared with control mice. Mechanistically, inhibition of HA synthesis led to increased macrophage apoptosis in vivo and in vitro. In addition, α-SMA (α-smooth muscle actin)-positive cells were reduced in the infarcted myocardium and in the border zone. In vitro, the myofibroblast response as measured by Acta2 mRNA expression was reduced by inhibition of HA synthesis and of CD44 signaling. Furthermore, Has2 KO fibroblasts were less able to contract collagen gels in vitro. The effects of HA/CD44 on fibroblasts and macrophages post-I/R might also affect intercellular cross talk because cardiac fibroblasts were activated by monocyte/macrophages and, in turn, protected macrophages from apoptosis. CONCLUSIONS: Increased HA synthesis contributes to postinfarct healing by supporting macrophage survival and by promoting the myofibroblast response. Additionally, imaging of cardiac HA by chemical exchange saturation transfer post-I/R might have translational value.


Assuntos
Matriz Extracelular/fisiologia , Hialuronan Sintases/deficiência , Ácido Hialurônico/biossíntese , Macrófagos/fisiologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Cicatrização/fisiologia , Actinas/metabolismo , Animais , Apoptose , Comunicação Celular/fisiologia , Sobrevivência Celular , Microambiente Celular/fisiologia , Matriz Extracelular/metabolismo , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/antagonistas & inibidores , Imageamento por Ressonância Magnética/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , Monócitos/fisiologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/citologia , Miofibroblastos/metabolismo , Miofibroblastos/fisiologia
13.
Int J Mol Sci ; 22(22)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34830059

RESUMO

BACKGROUND: Vascular injury induces the exposure of subendothelial extracellular matrix (ECM) important to serve as substrate for platelets to adhere to the injured vessel wall to avoid massive blood loss. Different ECM proteins are known to initiate platelet adhesion and activation. In atherosclerotic mice, the small, leucine-rich proteoglycan biglycan is important for the regulation of thrombin activity via heparin cofactor II. However, nothing is known about the role of biglycan for hemostasis and thrombosis under nonatherosclerotic conditions. METHODS: The role of biglycan for platelet adhesion and thrombus formation was investigated using a recombinant protein and biglycan knockout mice. RESULTS: The present study identified biglycan as important ECM protein for the adhesion and activation of platelets, and the formation of three-dimensional thrombi under flow conditions. Platelet adhesion to immobilized biglycan induces the reorganization of the platelet cytoskeleton. Mechanistically, biglycan binds and activates the major collagen receptor glycoprotein (GP)VI, because reduced platelet adhesion to recombinant biglycan was observed when GPVI was blocked and enhanced tyrosine phosphorylation in a GPVI-dependent manner was observed when platelets were stimulated with biglycan. In vivo, the deficiency of biglycan resulted in reduced platelet adhesion to the injured carotid artery and prolonged bleeding times. CONCLUSIONS: Loss of biglycan in the vessel wall of mice but not in platelets led to reduced platelet adhesion at the injured carotid artery and prolonged bleeding times, suggesting a crucial role for biglycan as ECM protein that binds and activates platelets via GPVI upon vessel injury.


Assuntos
Biglicano/genética , Biglicano/metabolismo , Adesividade Plaquetária/fisiologia , Glicoproteínas da Membrana de Plaquetas/metabolismo , Trombose/metabolismo , Animais , Plaquetas/metabolismo , Plaquetas/patologia , Artérias Carótidas/metabolismo , Lesões das Artérias Carótidas/metabolismo , Colágeno/metabolismo , Citoesqueleto/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Voluntários Saudáveis , Hemorragia/genética , Hemorragia/metabolismo , Humanos , Integrinas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Ativação Plaquetária/fisiologia , Adesividade Plaquetária/genética
14.
J Biol Chem ; 294(19): 7864-7877, 2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-30914479

RESUMO

4-Methylumbelliferone (4-MU) inhibits hyaluronan (HA) synthesis and is an approved drug used for managing biliary spasm. However, rapid and efficient glucuronidation is thought to limit its utility for systemically inhibiting HA synthesis. In particular, 4-MU in mice has a short half-life, causing most of the drug to be present as the metabolite 4-methylumbelliferyl glucuronide (4-MUG), which makes it remarkable that 4-MU is effective at all. We report here that 4-MUG contributes to HA synthesis inhibition. We observed that oral administration of 4-MUG to mice inhibits HA synthesis, promotes FoxP3+ regulatory T-cell expansion, and prevents autoimmune diabetes. Mice fed either 4-MUG or 4-MU had equivalent 4-MU:4-MUG ratios in serum, liver, and pancreas, indicating that 4-MU and 4-MUG reach an equilibrium in these tissues. LC-tandem MS experiments revealed that 4-MUG is hydrolyzed to 4-MU in serum, thereby greatly increasing the effective bioavailability of 4-MU. Moreover, using intravital 2-photon microscopy, we found that 4-MUG (a nonfluorescent molecule) undergoes conversion into 4-MU (a fluorescent molecule) and that 4-MU is extensively tissue bound in the liver, fat, muscle, and pancreas of treated mice. 4-MUG also suppressed HA synthesis independently of its conversion into 4-MU and without depletion of the HA precursor UDP-glucuronic acid (GlcUA). Together, these results indicate that 4-MUG both directly and indirectly inhibits HA synthesis and that the effective bioavailability of 4-MU is higher than previously thought. These findings greatly alter the experimental and therapeutic possibilities for HA synthesis inhibition.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Ácido Hialurônico/biossíntese , Himecromona/análogos & derivados , Linfócitos T Reguladores/metabolismo , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/patologia , Himecromona/farmacologia , Camundongos , Linfócitos T Reguladores/patologia
15.
Br J Cancer ; 123(6): 942-954, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32601464

RESUMO

BACKGROUND: The activation of the EGFR/Ras-signalling pathway in tumour cells induces a distinct chemokine repertoire, which in turn modulates the tumour microenvironment. METHODS: The effects of EGFR/Ras on the expression and translation of CCL20 were analysed in a large set of epithelial cancer cell lines and tumour tissues by RT-qPCR and ELISA in vitro. CCL20 production was verified by immunohistochemistry in different tumour tissues and correlated with clinical data. The effects of CCL20 on endothelial cell migration and tumour-associated vascularisation were comprehensively analysed with chemotaxis assays in vitro and in CCR6-deficient mice in vivo. RESULTS: Tumours facilitate progression by the EGFR/Ras-induced production of CCL20. Expression of the chemokine CCL20 in tumours correlates with advanced tumour stage, increased lymph node metastasis and decreased survival in patients. Microvascular endothelial cells abundantly express the specific CCL20 receptor CCR6. CCR6 signalling in endothelial cells induces angiogenesis. CCR6-deficient mice show significantly decreased tumour growth and tumour-associated vascularisation. The observed phenotype is dependent on CCR6 deficiency in stromal cells but not within the immune system. CONCLUSION: We propose that the chemokine axis CCL20-CCR6 represents a novel and promising target to interfere with the tumour microenvironment, and opens an innovative multimodal strategy for cancer therapy.


Assuntos
Quimiocina CCL20/biossíntese , Receptores ErbB/fisiologia , Neoplasias/imunologia , Microambiente Tumoral , Proteínas ras/fisiologia , Animais , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estadiamento de Neoplasias , Neoplasias/tratamento farmacológico , Neovascularização Patológica/etiologia , Receptores CCR6/fisiologia , Transdução de Sinais/fisiologia
16.
Basic Res Cardiol ; 115(4): 43, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32533377

RESUMO

Anaemia is frequently present in patients with acute myocardial infarction (AMI) and contributes to an adverse prognosis. We hypothesised that, besides reduced oxygen carrying capacity, anaemia is associated with (1) red blood cell (RBC) dysfunction and a reduced circulating nitric oxide (NO) pool, (2) compensatory enhancement of vascular and cardiac endothelial nitric oxide synthase (eNOS) activity, and (3) contribution of both, RBC dysfunction and reduced circulatory NO pool to left ventricular (LV) dysfunction and fatal outcome in AMI. In mouse models of subacute and chronic anaemia from repeated mild blood loss the circulating NO pool, RBC, cardiac and vascular function were analysed at baseline and in reperfused AMI. In anaemia, RBC function resulted in profound changes in membrane properties, enhanced turnover, haemolysis, dysregulation of intra-erythrocytotic redox state, and RBC-eNOS. RBC from anaemic mice and from anaemic patients with acute coronary syndrome impaired the recovery of contractile function of isolated mouse hearts following ischaemia/reperfusion. In anaemia, the circulating NO pool was reduced. The cardiac and vascular adaptation to anaemia was characterised by increased arterial eNOS expression and activity and an eNOS-dependent increase of end-diastolic left ventricular volume. Endothelial dysfunction induced through genetic or pharmacologic reduction of eNOS-activity abrogated the anaemia-induced cardio-circulatory compensation. Superimposed AMI was associated with decreased survival. In summary, moderate blood loss anaemia is associated with severe RBC dysfunction and reduced circulating NO pool. Vascular and cardiac eNOS are crucial for the cardio-circulatory adaptation to anaemia. RBC dysfunction together with eNOS dysfunction may contribute to adverse outcomes in AMI.


Assuntos
Adaptação Fisiológica/fisiologia , Anemia/fisiopatologia , Eritrócitos/patologia , Coração/fisiopatologia , Óxido Nítrico/sangue , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/fisiopatologia , Anemia/sangue , Animais , Artérias/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/sangue , Infarto do Miocárdio/fisiopatologia , Óxido Nítrico Sintase Tipo III/metabolismo
17.
Mol Ther ; 27(1): 46-58, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30528085

RESUMO

Insulin-like growth factor 1 (IGF1) is an anabolic hormone that controls the growth and metabolism of many cell types. However, IGF1 also mediates cardio-protective effects after acute myocardial infarction (AMI), but the underlying mechanisms and cellular targets are not fully understood. Here we demonstrate that short-term IGF1 treatment for 3 days after AMI improved cardiac function after 1 and 4 weeks. Regional wall motion was improved in ischemic segments, scar size was reduced, and capillary density increased in the infarcted area and the border zone. Unexpectedly, inducible inactivation of the IGF1 receptor (IGF1R) in cardiomyocytes did not attenuate the protective effect of IGF1. Sequential cardiac transcriptomic analysis indicated an altered myeloid cell response in the acute phase after AMI, and, notably, myeloid-cell Igf1r-/- mice lost the protective IGF1 function after I/R. In addition, IGF1 induced an M2-like anti-inflammatory phenotype in bone marrow-derived macrophages and enhanced the number of anti-inflammatory macrophages in heart tissue on day 3 after AMI in vivo. In summary, modulation of the acute inflammatory phase after AMI by IGF1 represents an effective mechanism to preserve cardiac function after I/R.


Assuntos
Fator de Crescimento Insulin-Like I/uso terapêutico , Células Mieloides/efeitos dos fármacos , Infarto do Miocárdio/tratamento farmacológico , Animais , Ecocardiografia , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase em Tempo Real , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo
18.
J Prosthet Dent ; 124(6): 780-786, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31955837

RESUMO

STATEMENT OF PROBLEM: Comparisons of the material qualities of pressed, milled, and 3D-printed occlusal devices are sparse, complicating informed decisions on material choice. PURPOSE: The purpose of this in vitro study was to compare the material properties of pressed, milled, and 3D-printed resins, as well as how these are affected by thermal aging. These data were then used to estimate the likely clinical performance of the tested materials. MATERIAL AND METHODS: Three pressed (ProBase Cold; Ivoclar Vivadent AG, Palapress clear; Kulzer GmbH, Aesthetic Blue clear; Candulor), 3 milled (Temp Premium Flexible Transpa; Zirkonzahn, idodentine PMMA transparent; Unión Dental S.A., Yamahachi PMMA clear; Yamahachi Dental MFG), and three 3D-printed (Freeprint splint; DETAX GmbH, LuxaPrint Ortho Plus; DMG GmbH, Nextdent Ortho Clear; Vertex-Dental B.V.) resin materials were evaluated. Flexural strength, Martens hardness (HM), Vickers hardness (HV), water sorption, water solubility, and surface topography were analyzed. The tests were carried out after 50 hours of water storage at 37 °C (baseline) and after simulated aging (50 hours of water storage at 37 °C, followed by 20 000 thermocycles [TC] at 5 °C and 55 °C). RESULTS: At baseline, the mean flexural strength values were 92.8 to 99.5 MPa for pressed, 95.1 to 122.0 MPa for milled, and 19.5 to 91.3 MPa for 3D-printed materials. After aging, these values were 87.6 to 93.5 MPa for pressed, 93.1 to 116.0 MPa for milled, and 13.0 to 63.3 MPa for 3D-printed resins. The mean HM values were 130.1 to 134.1 N/mm for pressed and 130.3 to 158.5 N/mm for milled resins. After aging, the mean HM ranged from 121.6 to 124.2 N/mm for pressed and 116.2 to 149.7 N/mm for milled resins. The mean HV values were 18.2 to 19.9 for pressed and 18.4 to 23.0 for milled resins before aging and 16.9 to 18.7 for pressed and 17.3 to 22.3 N/mm for milled resins after aging. Printed resins could not be measured. At baseline, the mean modulus of elasticity ranged from 4.6 to 4.8 GPa for pressed and from 4.7 to 5.3 GPa for milled resins. For 3D-printed resins, only 1 material could be measured (3.7 GPa). The mean sorption values were 8.6 to 9.2 µg/mm3 for pressed, 7.9 to 10.5 µg/mm3 for milled, and 9.2 to 21.2 µg/mm3 for additive resins. After aging, these values were 21.1 to 22.6 µg/mm3 for pressed, 20.5 to 23.7 µg/mm3 for milled, and 19.4 to 45.5 µg/mm3 for 3D-printed resins. The mean solubility values ranged from 0.3 to 1.4 µg/mm3 for pressed, 0.4 to 1.7 µg/mm3 for milled, and -3.5 to 11 µg/mm3 for 3D-printed materials. CONCLUSIONS: Pressed and milled resins can be considered equivalent in terms of their material properties. Relative to the pressed and milled resins, the 3D-printed resins had lower flexural strength and hardness values and higher water sorption and solubility.


Assuntos
Resinas Compostas , Estética Dentária , Materiais Dentários , Resistência à Flexão , Dureza , Teste de Materiais , Impressão Tridimensional , Estresse Mecânico , Propriedades de Superfície
19.
Clin Oral Implants Res ; 30(2): 178-186, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30629769

RESUMO

OBJECTIVE: This study evaluated the loading capacity of CAD/CAM-fabricated anterior feldspathic ceramic crowns bonded to one-piece zirconia implants with different cements. MATERIAL AND METHODS: Fifty one-piece zirconia implants were embedded in epoxy resin. The abutment aspect of one implant was optically scanned and a standardized upper canine was designed with CAD-software. Fifty feldspathic ceramic crowns were milled, polished, and mounted on the implants either without any cement, with a temporary cement or with three different composite resin cements after surface pretreatment as recommended by the manufacturers (n = 10). After storage in distilled water at 37°C for 24 hr, specimens were loaded until fracture on the palatal surface of the crown at an angle of 45° to the long axis of the implant and loads until fracture were detected and compared. Compressive strength of the investigated cement materials was determined. Statistical analyses were done with One-way ANOVA followed by post hoc Fisher LSD test (α = 0.05). RESULTS: The cements revealed significantly different compressive strength values (temporary cement: 37.1 ± 7.0 MPa; composite resin cements: 185.8 ± 21.3, 277.9 ± 22.1, and 389.0 ± 13.6 MPa, respectively). Load-at-fracture values had an overall mean value of 237.1 ± 58.2 N with no significant difference among the composite resin cements (p > 0.05). Fracture load values with the temporary cement or without cement were significantly lower (p < 0.002). CONCLUSIONS: CAD/CAM-fabricated anterior feldspathic ceramic crowns bonded to one-piece zirconia implants provide sufficient resistance to intraoral forces.


Assuntos
Silicatos de Alumínio , Coronantes , Cimentos Dentários , Compostos de Potássio , Próteses e Implantes , Zircônio , Cerâmica , Colagem Dentária , Suporte de Carga
20.
FASEB J ; 31(7): 2869-2880, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28325757

RESUMO

While radiotherapy is a mainstay for cancer therapy, pneumonitis and fibrosis constitute dose-limiting side effects of thorax and whole body irradiation. So far, the contribution of immune cells to disease progression is largely unknown. Here we studied the role of ecto-5'-nucelotidase (CD73)/adenosine-induced changes in the myeloid compartment in radiation-induced lung fibrosis. C57BL/6 wild-type or CD73-/- mice received a single dose of whole thorax irradiation (WTI, 15 Gy). Myeloid cells were characterized in flow cytometric, histologic, and immunohistochemical analyses as well as RNA analyses. WTI induced a pronounced reduction of alveolar macrophages in both strains that recovered within 6 wk. Fibrosis development in wild-type mice was associated with a time-dependent deposition of hyaluronic acid (HA) and increased expression of markers for alternative activation on alveolar macrophages. These include the antiinflammatory macrophage mannose receptor and arginase-1. Further, macrophages accumulated in organized clusters and expressed profibrotic mediators at ≥25 wk after irradiation (fibrotic phase). Irradiated CD73-/- mice showed an altered regulation of components of the HA system and no clusters of alternatively activated macrophages. We speculate that accumulation of alternatively activated macrophages in organized clusters represents the origins of fibrotic foci after WTI and is promoted by a cross-talk between HA, CD73/adenosine signaling, and other profibrotic mediators.-De Leve, S., Wirsdörfer, F., Cappuccini, F., Schütze, A., Meyer, A. V., Röck, K., Thompson, L. F., Fischer, J. W., Stuschke, M., Jendrossek, V. Loss of CD73 prevents accumulation of alternatively activated macrophages and the formation of prefibrotic macrophage clusters in irradiated lungs.


Assuntos
5'-Nucleotidase/metabolismo , Regulação Enzimológica da Expressão Gênica/fisiologia , Pulmão/citologia , Pulmão/efeitos da radiação , Macrófagos Alveolares/efeitos da radiação , Adenosina/metabolismo , Animais , Antígeno CD11b/metabolismo , Adesão Celular , Ácido Hialurônico/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fibrose Pulmonar/etiologia , Transdução de Sinais
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