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Spatiotemporal-controlled second messengers alter molecular interactions of central signaling nodes for ensuring physiological signal transmission. One prototypical second messenger molecule which modulates kinase signal transmission is the cyclic-adenosine monophosphate (cAMP). The main proteinogenic cellular effectors of cAMP are compartmentalized protein kinase A (PKA) complexes. Their cell-type specific compositions precisely coordinate substrate phosphorylation and proper signal propagation which is indispensable for numerous cell-type specific functions. Here we present evidence that TAF15, which is implicated in the etiology of amyotrophic lateral sclerosis, represents a novel nuclear PKA substrate. In cross-linking and immunoprecipitation experiments (iCLIP) we showed that TAF15 phosphorylation alters the binding to target transcripts related to mRNA maturation, splicing and protein-binding related functions. TAF15 appears to be one of multiple PKA substrates that undergo RNA-binding dynamics upon phosphorylation. We observed that the activation of the cAMP-PKA signaling axis caused a change in the composition of a collection of RNA species that interact with TAF15. This observation appears to be a broader principle in the regulation of molecular interactions, as we identified a significant enrichment of RNA-binding proteins within endogenous PKA complexes. We assume that phosphorylation of RNA-binding domains adds another layer of regulation to binary protein-RNAs interactions with consequences to RNA features including binding specificities, localization, abundance and composition.
Assuntos
Esclerose Lateral Amiotrófica , Fatores Associados à Proteína de Ligação a TATA , Humanos , Proteínas Quinases Dependentes de AMP Cíclico , Fosforilação , AMP Cíclico , RNARESUMO
AIM: Sex-specific analyses of direct head-to-head comparisons between newer P2Y12 inhibitors are limited. This study was conducted to assess the efficacy and safety of ticagrelor versus prasugrel in women and men with acute coronary syndromes (ACS) planned for an invasive strategy. METHODS: This pre-specified analysis of the ISAR-REACT 5 trial included 956 women and 3,062 men with ACS randomly assigned to either ticagrelor or prasugrel. The primary endpoint was the 12-month incidence of death, myocardial infarction, or stroke; the safety endpoint was the 12-month incidence of bleeding (type 3-5 according to the Bleeding Academic Research Consortium [BARC]). RESULTS: The primary endpoint occurred in 42 women (8.9%) in the ticagrelor group and 39 women (8.3%) in the prasugrel group (hazard ratio [HR]=1.10, 95% confidence interval [CI] 0.71-1.70, P=0.657) and in 142 men (9.4%) in the ticagrelor group and 98 men (6.5%) in the prasugrel group (HR=1.47 [1.13-1.90], P=0.004; P for interaction [Pint]=0.275). BARC type 3-5 bleeding occurred in 36 women (9.7%) in the ticagrelor group and 34 women (9.7%) in the prasugrel group (HR=1.04 [0.65-1.67], P=0.856) and in 59 men in the ticagrelor group (4.4%) and 46 men (3.6%) in the prasugrel group (HR=1.24 [0.85-1.83], P=0.266; Pint=0.571). CONCLUSIONS: Although there was no significant interaction between sex and treatment effect of study drugs, the superior efficacy of prasugrel was more evident among men. No difference in bleeding between the two study groups was seen for both women and men.
Assuntos
Síndrome Coronariana Aguda , Cloridrato de Prasugrel , Ticagrelor , Síndrome Coronariana Aguda/tratamento farmacológico , Feminino , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Hemorragia/epidemiologia , Humanos , Masculino , Intervenção Coronária Percutânea , Inibidores da Agregação Plaquetária/efeitos adversos , Cloridrato de Prasugrel/efeitos adversos , Ticagrelor/efeitos adversos , Resultado do TratamentoRESUMO
OBJECTIVES: To compare vascular closure devices (VCD) with manual compression (MC) in patients on chronic oral anticoagulation (OAC) who undergo diagnostic coronary angiography in terms of vascular access-site complications. METHODS: This is a subanalysis of 604 patients that had undergone transfemoral diagnostic coronary angiography and were randomly assigned to arteriotomy closure with either VCDs (intravascular FemoSeal VCD or extravascular EXOSEAL VCD) or MC within the large scale, randomized ISAR-CLOSURE trial. Primary endpoint was the composite of access-site-related vascular complications at 30 days. Secondary endpoints were time to hemostasis and repeat MC. RESULTS: Vascular access-site complications were similar in patients assigned to VCDs compared to MC (8.2% vs 10.6%; P=.33). There was no interaction of treatment effect and OAC (P interaction = 0.59). Rates of pseudoaneurysms were lower with VCDs (0.8% vs 3.2%; P=.02). Time to hemostasis was significantly shortened with VCDs compared to MC (1 [IQR 0.5-2.0] min vs 12 [IQR 10-15] min; P<.001). There was no difference regarding repeat MC in both groups (VCD 1.5% vs MC 0.5%; P=.23). Time to hemostasis (0.5 [0.2-1.0] min, vs 2.0 [1.75-2.0] min; P<.001) and closure device failure (3.7% vs 17.2%; P<.001) were lower with the intravascular VCD, compared with the extravascular VCD. CONCLUSIONS: In patients on chronic OAC undergoing transfemoral diagnostic coronary angiography, the use of VCDs was comparable to MC regarding the primary combined endpoint of vascular access-site related complications. VCDs reduced the occurrence of pseudoaneurysms and time to hemostasis.
Assuntos
Dispositivos de Oclusão Vascular , Anticoagulantes/efeitos adversos , Artéria Femoral/diagnóstico por imagem , Técnicas Hemostáticas , Humanos , Punções/efeitos adversos , Resultado do TratamentoRESUMO
Event probability has been traditionally regarded as the major determinant of P3b amplitudes, with amplitudes increasing when stimuli are less likely. Here we show in a simple variant of the continuous performance task that this "oddball effect" does not universally apply. Stimuli were a continuous series of (A or B) -> (X or Y) pairs, with the letter X requiring a key-press response and occurring in 80% of trials after A and in 20% after B (vice versa the Y). P3b amplitudes were equally large with probable and improbable occurrence of X. This was in contrast to visual Mismatch Negativity which was consistently larger with less probable stimuli, and also in contrast to no-go P3 amplitudes, which were larger with improbable than probable Y. The only effect on P3b amplitude was due to stimulus onset asynchronies (SOA): P3b was larger with SOAs of 2000 ms compared to 1500 ms. This result dovetails with previous evidence in the oddball task that the main determinant of the oddball effect is not event probability but rather time interval between stimuli. The absence of probability effects on P3b was in sharp contrast to the presence of these effects on no-go P3. Implications are discussed for theories about the psychological meaning of the P3b component.
Assuntos
Potenciais Evocados P300/fisiologia , Inibição Psicológica , Desempenho Psicomotor/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Atividade Motora/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Probabilidade , Fatores de Tempo , Adulto JovemRESUMO
BACKGROUND: The value of vascular closure devices (VCD) in women undergoing transfemoral catheterization has not been sufficiently investigated. METHODS AND RESULTS: This is a sex-specific analysis of 1395 women enrolled in a large-scale, randomized, multicenter trial, in which patients undergoing transfemoral diagnostic coronary angiography were randomly assigned in a 1:1:1 ratio to arteriotomy closure with an intravascular VCD, extravascular VCD, or manual compression (MC). Primary objective was to assess the safety and efficacy of 2 different VCD compared with MC regarding vascular access-site complications at 30 days. A secondary comparison was between 2 different types of contemporary VCD. Overall, women were at higher risk for vascular access-site complications compared with men (9.0% versus 6.4%; P=0.002). Vascular access-site complications were comparable in women assigned to VCD and MC (8.6% versus 9.8%; P=0.451). There was no interaction of treatment effect and sex ( Pinteraction=0.970). Time to hemostasis was significantly shortened with VCD compared with MC (1 [interquartile range, 0.5-2.0] minutes) versus 11 [interquartile range, 10-15] minutes; P<0.001); however, more women with VCD required repeat MC (2.4% versus 0.6%; P=0.018). The use of the intravascular compared with the extravascular VCD was associated with a numerical reduction in vascular access-site complications (6.6% versus 10.7%; P=0.027) and significant reductions in time to hemostasis and VCD failure. CONCLUSIONS: In women undergoing diagnostic coronary angiography via the common femoral artery, VCD and MC provided comparable safety, while time to hemostasis was reduced with VCD. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01389375.
Assuntos
Cateterismo Periférico/métodos , Angiografia Coronária/métodos , Artéria Femoral , Hemorragia/prevenção & controle , Técnicas Hemostáticas/instrumentação , Dispositivos de Oclusão Vascular , Idoso , Cateterismo Periférico/efeitos adversos , Angiografia Coronária/efeitos adversos , Desenho de Equipamento , Feminino , Hemorragia/etiologia , Técnicas Hemostáticas/efeitos adversos , Humanos , Pessoa de Meia-Idade , Pressão , Punções , Fatores Sexuais , Fatores de Tempo , Resultado do TratamentoRESUMO
In the Simon task, participants respond faster when the task-irrelevant stimulus position and the response position are corresponding, for example on the same side, compared to when they have a non-corresponding relation. Interestingly, this Simon effect is reduced after non-corresponding trials. Such sequential effects can be explained in terms of a more focused processing of the relevant stimulus dimension due to increased cognitive control, which transfers from the previous non-corresponding trial (conflict adaptation effects). Alternatively, sequential modulations of the Simon effect can also be due to the degree of trial-to-trial repetitions and alternations of task features, which is confounded with the correspondence sequence (feature integration effects). In the present study, we used a spatially two-dimensional Simon task with vertical response keys to examine the contribution of adaptive cognitive control and feature integration processes to the sequential modulation of the Simon effect. The two-dimensional Simon task creates correspondences in the vertical as well as in the horizontal dimension. A trial-by-trial alternation of the spatial dimension, for example from a vertical to a horizontal stimulus presentation, generates a subset containing no complete repetitions of task features, but only complete alternations and partial repetitions, which are equally distributed over all correspondence sequences. In line with the assumed feature integration effects, we found sequential modulations of the Simon effect only when the spatial dimension repeated. At least for the horizontal dimension, this pattern was confirmed by the parietal P3b, an event-related potential that is assumed to reflect stimulus-response link processes. Contrary to conflict adaptation effects, cognitive control, measured by the fronto-central N2 component of the EEG, was not sequentially modulated. Overall, our data provide behavioral as well as electrophysiological evidence for feature integration effects contributing to sequential modulations of the Simon effect.
RESUMO
IMPORTANCE: The role of vascular closure devices (VCD) for the achievement of hemostasis in patients undergoing transfemoral coronary angiography remains controversial. OBJECTIVE: To compare outcomes with the use of 2 hemostasis strategies after diagnostic coronary angiography performed via transfemoral access-a VCD-based strategy with 2 types of devices, an intravascular device and an extravascular device, vs standard manual compression. The primary hypothesis to be tested was that femoral hemostasis achieved through VCD is noninferior to manual compression in terms of vascular access-site complications. A secondary objective was the comparison of the 2 types of VCD. DESIGN, SETTING, AND PARTICIPANTS: Randomized, large-scale, multicenter, open-label clinical trial. We enrolled 4524 patients undergoing coronary angiography with a 6 French sheath via the common femoral artery from April 2011 through May 2014 in 4 centers in Germany. Last 30-day follow-up was performed in July 2014. INTERVENTIONS: After angiography of the access site, patients were randomized to hemostasis with an intravascular VCD, extravascular VCD, or manual compression in a 1:1:1 ratio. MAIN OUTCOMES AND MEASURES: Primary end point: the composite of access site-related vascular complications at 30 days after randomization with a 2% noninferiority margin. Secondary end points: time to hemostasis, repeat manual compression, and VCD failure. An α-level of .025 was chosen for primary and secondary comparisons. RESULTS: Of the 4524 enrolled patients, 3015 were randomly assigned to a VCD group (1509 received intravascular VCD and 1506 received extravascular VCD) and 1509 patients were randomly assigned to the manual compression group. Before hospital discharge, duplex sonography of the access site was performed in 4231 (94%) patients. The primary end point was observed in 208 patients (6.9%) assigned to receive a VCD and 119 patients (7.9%) assigned to manual compression (difference, -1.0% [1-sided 97.5% CI, 0.7%]; P for noninferiority<.001). Time to hemostasis was significantly shorter in patients with VCD (1 minute [interquartile range {IQR}, 0.5-2.0]), vs manual compression (10 minutes [IQR, 10-15]; P < .001). Time to hemostasis was significantly shorter among patients with intravascular VCD (0.5 minute [IQR, 0.2-1.0]), vs extravascular VCD (2.0 minutes [IQR, 1.0-2.0]; P <.001) and closure device failure was also significantly lower among those with intravascular vs extravascular VCD (80 patients [5.3%], vs 184 patients [12.2%]; P < .001). CONCLUSIONS AND RELEVANCE: In patients undergoing transfemoral coronary angiography, VCDs were noninferior to manual compression in terms of vascular access-site complications and reduced time to hemostasis. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01389375.
Assuntos
Angiografia Coronária/efeitos adversos , Técnicas Hemostáticas , Pressão , Dispositivos de Oclusão Vascular , Idoso , Cateterismo Cardíaco , Angiografia Coronária/métodos , Feminino , Artéria Femoral , Hemostasia , Humanos , Masculino , Pessoa de Meia-Idade , Punções , Fatores de TempoRESUMO
AIMS: Vascular closure devices (VCD) have been introduced into clinical practice with the aim of increasing the procedural efficiency and clinical safety of coronary angiography. However, clinical studies comparing VCD and manual compression have yielded mixed results, and large randomised clinical trials comparing the two strategies are missing. Moreover, comparative efficacy studies between different VCD in routine clinical use are lacking. METHODS AND RESULTS: The Instrumental Sealing of ARterial puncture site - CLOSURE device versus manual compression (ISAR-CLOSURE) trial is a prospective, randomised clinical trial designed to compare the outcomes associated with the use of VCD or manual compression to achieve femoral haemostasis. The test hypothesis is that femoral haemostasis after coronary angiography achieved using VCD is not inferior to manual compression in terms of access-site-related vascular complications. Patients undergoing coronary angiography via the common femoral artery will be randomised in a 1:1:1 fashion to receive FemoSeal VCD, EXOSEAL VCD or manual compression. The primary endpoint is the incidence of the composite of arterial access-related complications (haematoma ≥5 cm, pseudoaneurysm, arteriovenous fistula, access-site-related bleeding, acute ipsilateral leg ischaemia, the need for vascular surgical/interventional treatment or documented local infection) at 30 days after randomisation. According to power calculations based on non-inferiority hypothesis testing, enrolment of 4,500 patients is planned. The trial is registered at www.clinicaltrials.gov (study identifier: NCT01389375). CONCLUSIONS: The safety of VCD as compared to manual compression in patients undergoing transfemoral coronary angiography remains an issue of clinical equipoise. The aim of the ISAR-CLOSURE trial is to assess whether femoral haemostasis achieved through the use of VCD is non-inferior to manual compression in terms of access-site-related vascular complications.
Assuntos
Angiografia Coronária , Artéria Femoral , Hemorragia/prevenção & controle , Hemostasia , Técnicas Hemostáticas/instrumentação , Projetos de Pesquisa , Dispositivos de Acesso Vascular , Protocolos Clínicos , Angiografia Coronária/efeitos adversos , Desenho de Equipamento , Alemanha , Hemorragia/sangue , Hemorragia/etiologia , Técnicas Hemostáticas/efeitos adversos , Humanos , Pressão , Estudos Prospectivos , Punções , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVES: To prospectively assess the outcome of percutaneous edge-to-edge repair in patients with degenerative versus functional mitral regurgitation (MR). BACKGROUND: The optimal patient population eligible for percutaneous edge-to-edge repair has yet to be defined. METHODS: We analyzed 119 patients treated by percutaneous edge-to-edge repair for symptomatic MR, 72 patients with degenerative and 47 patients with functional MR. The primary endpoints were defined as procedural success (MR grade reduction ≥1 grade) as well as a composite endpoint defined as freedom from MR 3+ or 4+, mitral valve reintervention and death 12 months after clip implantation. In patients with successful clip placement we further analyzed MR grade, New York Heart Association (NYHA) functional class, distance in the 6 min walking test and left ventricular volumes 12 months after clip implantation. RESULTS: The primary success rate of all intended clipping procedures was 83.3% for degenerative and 89.4% for functional MR (P = 0.42). Regarding the composite endpoint we observed an event free survival of 59.7% in patients treated for degenerative MR and 63.8% in patients treated for functional MR (P = 0.73). We observed a highly significant reduction in MR grade as well as improvement in NYHA functional status in both groups 12 months after clip implantation. However, there was a more pronounced MR grade reduction in patients treated for degenerative MR compared with patients treated for functional MR. CONCLUSIONS: Percutaneous edge-to-edge repair of the mitral valve is feasible and comparably effective in patients with degenerative and functional MR.
Assuntos
Implante de Prótese de Valva Cardíaca/métodos , Insuficiência da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Função Ventricular Esquerda/fisiologia , Idoso , Cateterismo Cardíaco , Ecocardiografia , Feminino , Seguimentos , Humanos , Masculino , Insuficiência da Valva Mitral/fisiopatologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
AIMS: Single leaflet clip attachment (SLA) is a prevalent complication in percutaneous edge-to-edge repair of the mitral valve, leading to the recurrence of significant mitral regurgitation. The objective of this retrospective analysis was to evaluate a novel 3-D transoesophageal echocardiographic method for the assessment of clip attachment to the mitral leaflets. METHODS AND RESULTS: We analysed a total of 87 patients treated for symptomatic mitral regurgitation. In 47 patients, clip attachment to the leaflets was assessed by conventional 2-D transoesophageal echocardiography supported by biplane TEE images (biplane TEE group). In 40 patients, clip attachment to the leaflets was assessed by the intraprocedural 3-D volume method in addition to the conventional method (volumetric TEE group). The primary endpoint was defined as clip complications consisting of SLA and clip displacement at any time after clip implantation. Clip complications occurred in nine patients (19.1%) in the biplane TEE group and in two patients (5%) in the volumetric TEE group (p=0.06). Regarding the grade of mitral regurgitation, in the follow-up period we observed a more pronounced deterioration in the biplane TEE group than in the volumetric TEE group. CONCLUSIONS: These findings suggest that the additional use of 3-D volumetric transoesophageal echocardiography for the assessment of clip attachment to the mitral leaflets may contribute to a reduced rate of subsequent clip complications.
Assuntos
Cateterismo Cardíaco/instrumentação , Ecocardiografia Tridimensional , Ecocardiografia Transesofagiana , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/terapia , Valva Mitral/diagnóstico por imagem , Instrumentos Cirúrgicos , Idoso , Idoso de 80 Anos ou mais , Cateterismo Cardíaco/efeitos adversos , Desenho de Equipamento , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/fisiopatologia , Valor Preditivo dos Testes , Recidiva , Estudos Retrospectivos , Resultado do TratamentoRESUMO
BACKGROUND: Post-implantation therapies to optimize cardiac resynchronization therapy (CRT) focus on adjustments of the atrio-ventricular (AV) delay and ventricular-to-ventricular (VV) interval. However, there is little consensus on how to achieve best resynchronization with these parameters. The aim of this study was to examine a novel combination of doppler echocardiography (DE) and three-dimensional echocardiography (3DE) for individualized optimization of device based AV delays and VV intervals compared to empiric programming. METHODS: 25 recipients of CRT (male: 56%, mean age: 67 years) were included in this study. Ejection fraction (EF), the primary outcome parameter, and left ventricular (LV) dimensions were evaluated by 3DE before CRT (baseline), after AV delay optimization while pacing the ventricles simultaneously (empiric VV interval programming) and after individualized VV interval optimization. For AV delay optimization aortic velocity time integral (AoVTI) was examined in eight different AV delays, and the AV delay with the highest AoVTI was programmed. For individualized VV interval optimization 3DE full-volume datasets of the left ventricle were obtained and analyzed to derive a systolic dyssynchrony index (SDI), calculated from the dispersion of time to minimal regional volume for all 16 LV segments. Consecutively, SDI was evaluated in six different VV intervals (including LV or right ventricular preactivation), and the VV interval with the lowest SDI was programmed (individualized optimization). RESULTS: EF increased from baseline 23±7% to 30±8 (p<0.001) after AV delay optimization and to 32±8% (p<0.05) after individualized optimization with an associated decrease of end-systolic volume from a baseline of 138±60 ml to 115±42 ml (p<0.001). Moreover, individualized optimization significantly reduced SDI from a baseline of 14.3±5.5% to 6.1±2.6% (p<0.001). CONCLUSIONS: Compared with empiric programming of biventricular pacemakers, individualized echocardiographic optimization with the integration of 3-dimensional indices into the optimization protocol acutely improved LV systolic function and decreased ESV and can be used to select the optimal AV delay and VV interval in CRT.
Assuntos
Terapia de Ressincronização Cardíaca/métodos , Ecocardiografia Doppler/métodos , Ecocardiografia Tridimensional/métodos , Hemodinâmica , Idoso , Terapia de Ressincronização Cardíaca/normas , Humanos , Masculino , Métodos , Volume Sistólico , Disfunção Ventricular EsquerdaRESUMO
Herbal tea can be prepared by infusion or maceration at room temperature resulting in different compositions of extractable constituents, which possibly influences the mode of action or safety profile. Knowledge on this topic is limited. The aim of this study was to investigate the substantial differences between infusion and maceration as recommended preparation methods for the preparation of herbal mistletoe tea, a traditional remedy against cardiovascular diseases. No active substances are known but analytical marker substances such as proteins, triterpenoids, phenylpropane derivatives and flavonoids can be quantified within the herb and the different herbal tea preparations. Whereas phenylpropane derivatives were completely extracted by infusion and maceration, neither method dissolved viscotoxins. 43% of mistletoe lectins were extracted by maceration, whereas by infusion they are inactivated by thermal degradation. By contrast, oleanolic acid and betulinic acid are present in higher concentrations in infusates compared with macerates, but even infusion extracted less than 2%. Infusion extracted 43% of flavonoid-like substances and maceration only 31%. In conclusion this study determines some differences between both extraction methods on the profile of solved substances. The relevance of it should be determined in studies dealing with the efficacy of herbal mistletoe tea.
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BACKGROUND: Erythropoietin improves myocardial function in experimental models of myocardial infarction. The aim of the present study was to determine the value of erythropoietin in patients with acute ST-elevation myocardial infarction. METHODS AND RESULTS: This randomized, double-blind study included 138 patients admitted with acute ST-elevation myocardial infarction and treated with primary percutaneous coronary intervention. Patients were randomly assigned to receive epoetin-ß (3.33×104 U, n=68) or placebo (n=70) immediately and at 24 and 48 hours after percutaneous coronary intervention. The primary end point was left ventricular ejection fraction after 6 months measured by MRI. Other end points included infarct size at 5 days and 6 months. Clinical adverse events (death, recurrent myocardial infarction, stroke, and infarct-related artery revascularization) were investigated at 30 days and 6 months. Left ventricular ejection fraction at 6-month follow-up was 52.0±9.1% in the erythropoietin group compared with 51.8±9.3% in the placebo group (P=0.92). Five days after percutaneous coronary intervention, left ventricular ejection fraction was 49.4±8.0% in the erythropoietin group and 50.8±7.3% in the placebo group (P=0.32); infarct size was 26.8±20.9% and 28.3±24.4% (P=0.76) and decreased to 17.3±14.3% and 20.9±16.4% at 6-month follow-up (P=0.27). The cumulative 6-month incidence of death, recurrent myocardial infarction, stroke or target vessel revascularization was 13.2% in the erythropoietin group and 5.7% in the placebo group (hazard ratio, 2.36; 95% confidence interval, 0.73 to 7.66; P=0.15). CONCLUSIONS: In patients with acute ST-elevation myocardial infarction treated with primary percutaneous coronary intervention, erythropoietin treatment did not improve left ventricular ejection fraction or reduce infarct size but may increase clinical adverse events. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00390832.
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Angioplastia , Eritropoetina/administração & dosagem , Eritropoetina/efeitos adversos , Infarto do Miocárdio/terapia , Miocárdio/patologia , Idoso , Método Duplo-Cego , Eletrocardiografia , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Revascularização Miocárdica , Recidiva , Acidente Vascular Cerebral , Volume Sistólico , Análise de Sobrevida , Resultado do TratamentoRESUMO
In order to identify novel genes encoding enzymes involved in the terminal step of triacylglycerol (TAG) formation, a database search was carried out in the genome of the unicellular photoautotrophic green alga Ostreococcus tauri. The search led to the identification of three putative type 2 acyl-CoA:diacylglycerol acyltransferase-like sequences (DGAT; EC 2.3.1.20), and revealed the absence of any homolog to type 1 or type 3 DGAT sequence in the genome of O. tauri. For two of the cDNA sequences (OtDGAT2A and B) enzyme activity was detected by heterologous expression in Saccharomyces cerevisiae mutant strains with impaired TAG metabolism. However, activity of OtDGAT2A was too low for further analysis. Analysis of their amino acid sequences showed that they share limited identity with other DGAT2 from different plant species, such as Ricinus communis and Vernicia fordii with approximately 25 to 30% identity. Lipid analysis of the mutant yeast cells revealed that OtDGAT2B showed broad substrate specificity accepting saturated as well as mono- and poly-unsaturated acyl-CoAs as substrates.
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Acil Coenzima A/metabolismo , Clorófitas/genética , DNA de Plantas , Diacilglicerol O-Aciltransferase/genética , Expressão Gênica , Genes de Plantas , Triglicerídeos/genética , Sequência de Aminoácidos , Sequência de Bases , Clorófitas/enzimologia , Ácidos Graxos/análise , Genoma de Planta , Magnoliopsida/genética , Mutação , Saccharomyces cerevisiae , Homologia de Sequência , Especificidade por Substrato , Triglicerídeos/biossínteseRESUMO
The accumulation of smooth muscle and endothelial cells is essential for remodeling and repair of injured blood vessel walls. Bone marrow-derived progenitor cells have been implicated in vascular repair and remodeling; however, the mechanisms underlying their recruitment to the site of injury remain elusive. Here, using real-time in vivo fluorescence microscopy, we show that platelets provide the critical signal that recruits CD34+ bone marrow cells and c-Kit+ Sca-1+ Lin- bone marrow-derived progenitor cells to sites of vascular injury. Correspondingly, specific inhibition of platelet adhesion virtually abrogated the accumulation of both CD34+ and c-Kit+ Sca-1+ Lin- bone marrow-derived progenitor cells at sites of endothelial disruption. Binding of bone marrow cells to platelets involves both P-selectin and GPIIb integrin on platelets. Unexpectedly, we found that activated platelets secrete the chemokine SDF-1alpha, thereby supporting further primary adhesion and migration of progenitor cells. These findings establish the platelet as a major player in the initiation of vascular remodeling, a process of fundamental importance for vascular repair and pathological remodeling after vascular injury.