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1.
Immunity ; 56(7): 1578-1595.e8, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37329888

RESUMO

It is currently not well known how necroptosis and necroptosis responses manifest in vivo. Here, we uncovered a molecular switch facilitating reprogramming between two alternative modes of necroptosis signaling in hepatocytes, fundamentally affecting immune responses and hepatocarcinogenesis. Concomitant necrosome and NF-κB activation in hepatocytes, which physiologically express low concentrations of receptor-interacting kinase 3 (RIPK3), did not lead to immediate cell death but forced them into a prolonged "sublethal" state with leaky membranes, functioning as secretory cells that released specific chemokines including CCL20 and MCP-1. This triggered hepatic cell proliferation as well as activation of procarcinogenic monocyte-derived macrophage cell clusters, contributing to hepatocarcinogenesis. In contrast, necrosome activation in hepatocytes with inactive NF-κB-signaling caused an accelerated execution of necroptosis, limiting alarmin release, and thereby preventing inflammation and hepatocarcinogenesis. Consistently, intratumoral NF-κB-necroptosis signatures were associated with poor prognosis in human hepatocarcinogenesis. Therefore, pharmacological reprogramming between these distinct forms of necroptosis may represent a promising strategy against hepatocellular carcinoma.


Assuntos
Neoplasias Hepáticas , NF-kappa B , Humanos , NF-kappa B/metabolismo , Proteínas Quinases/metabolismo , Necroptose , Inflamação/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Apoptose
2.
Nature ; 608(7924): 766-777, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35948637

RESUMO

Myocardial infarction is a leading cause of death worldwide1. Although advances have been made in acute treatment, an incomplete understanding of remodelling processes has limited the effectiveness of therapies to reduce late-stage mortality2. Here we generate an integrative high-resolution map of human cardiac remodelling after myocardial infarction using single-cell gene expression, chromatin accessibility and spatial transcriptomic profiling of multiple physiological zones at distinct time points in myocardium from patients with myocardial infarction and controls. Multi-modal data integration enabled us to evaluate cardiac cell-type compositions at increased resolution, yielding insights into changes of the cardiac transcriptome and epigenome through the identification of distinct tissue structures of injury, repair and remodelling. We identified and validated disease-specific cardiac cell states of major cell types and analysed them in their spatial context, evaluating their dependency on other cell types. Our data elucidate the molecular principles of human myocardial tissue organization, recapitulating a gradual cardiomyocyte and myeloid continuum following ischaemic injury. In sum, our study provides an integrative molecular map of human myocardial infarction, represents an essential reference for the field and paves the way for advanced mechanistic and therapeutic studies of cardiac disease.


Assuntos
Remodelamento Atrial , Montagem e Desmontagem da Cromatina , Perfilação da Expressão Gênica , Infarto do Miocárdio , Análise de Célula Única , Remodelação Ventricular , Remodelamento Atrial/genética , Estudos de Casos e Controles , Cromatina/genética , Epigenoma , Humanos , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fatores de Tempo , Remodelação Ventricular/genética
3.
Arterioscler Thromb Vasc Biol ; 43(2): 192-202, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36579644

RESUMO

Ischemic heart disease including myocardial infarction is still the leading cause of death worldwide. Although the survival early after myocardial infarction has been significantly improved by the introduction of percutaneous coronary intervention, long-term morbidity and mortality remain high. The elevated long-term mortality is mainly driven by cardiac remodeling processes triggering ischemic heart failure and electric instability. Despite the new developments in pharmaco-therapy of heart failure, we still lack targeted therapies for cardiac remodeling and fibrosis. Single-cell and genomic technologies allow us to map the human heart at unprecedented resolution and allow to gain insights into cellular and molecular heterogeneity. However, these technologies rely on digested tissue and isolated cells or nuclei and thus lack spatial information. Spatial information is critical to understand tissue homeostasis and disease and can be utilized to identify disease-driving cell populations and mechanisms including cellular cross-talk. Here, we discuss recent advances in single-cell and spatial genomic technologies that give insights into cellular and molecular mechanisms of cardiac remodeling after injury and can be utilized to identify novel therapeutic targets and pave the way toward new therapies in heart failure.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Isquemia Miocárdica , Humanos , Remodelação Ventricular , Multiômica , Infarto do Miocárdio/genética , Infarto do Miocárdio/terapia , Infarto do Miocárdio/complicações , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/terapia
4.
Arch Toxicol ; 97(9): 2303-2328, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37402810

RESUMO

Genotoxicity data are mainly interpreted in a qualitative way, which typically results in a binary classification of chemical entities. For more than a decade, there has been a discussion about the need for a paradigm shift in this regard. Here, we review current opportunities, challenges and perspectives for a more quantitative approach to genotoxicity assessment. Currently discussed opportunities mainly include the determination of a reference point (e.g., a benchmark dose) from genetic toxicity dose-response data, followed by calculation of a margin of exposure (MOE) or derivation of a health-based guidance value (HBGV). In addition to new opportunities, major challenges emerge with the quantitative interpretation of genotoxicity data. These are mainly rooted in the limited capability of standard in vivo genotoxicity testing methods to detect different types of genetic damage in multiple target tissues and the unknown quantitative relationships between measurable genotoxic effects and the probability of experiencing an adverse health outcome. In addition, with respect to DNA-reactive mutagens, the question arises whether the widely accepted assumption of a non-threshold dose-response relationship is at all compatible with the derivation of a HBGV. Therefore, at present, any quantitative genotoxicity assessment approach remains to be evaluated case-by-case. The quantitative interpretation of in vivo genotoxicity data for prioritization purposes, e.g., in connection with the MOE approach, could be seen as a promising opportunity for routine application. However, additional research is needed to assess whether it is possible to define a genotoxicity-derived MOE that can be considered indicative of a low level of concern. To further advance quantitative genotoxicity assessment, priority should be given to the development of new experimental methods to provide a deeper mechanistic understanding and a more comprehensive basis for the analysis of dose-response relationships.


Assuntos
Dano ao DNA , Mutagênicos , Mutagênicos/toxicidade , Mutagênicos/análise , DNA , Medição de Risco , Testes de Mutagenicidade/métodos
5.
Int J Mol Sci ; 23(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36498897

RESUMO

Myocardial infarction is remains the leading cause of death in developed countries. Recent data show that the composition of the extracellular matrix might differ despite similar heart function and infarction sizes. Because collagen is the main component of the extracellular matrix, we hypothesized that changes in inflammatory cell recruitment influence the synthesis of different collagen subtypes in myofibroblasts, thus changing the composition of the scar. We found that neutrophils sustain the proliferation of fibroblasts, remodeling, differentiation, migration and inflammation, predominantly by IL-1 and PPARγ pathways (n = 3). They also significantly inhibit the mRNA expression of fibrillar collagen, maintaining a reduced stiffness in isolated myofibroblasts (n = 4-5). Reducing the neutrophil infiltration in CCR1-/- resulted in increased mRNA expression of collagen 11, moderate expression of collagen 19 and low expression of collagen 13 and 26 in the scar 4 weeks post infarction compared with other groups (n = 3). Mononuclear cells increased the synthesis of all collagen subtypes and upregulated the NF-kB, angiotensin II and PPARδ pathways (n = 3). They increased the synthesis of collagen subtypes 1, 3, 5, 16 and 23 but reduced the expression of collagens 5 and 16 (n = 3). CCR2-/- scar tissue showed higher levels of collagen 13 (n = 3), in association with a significant reduction in stiffness (n = 4-5). Upregulation of the inflammation-related genes in myofibroblasts mostly modulated the fibrillar collagen subtypes, with less effect on the FACIT, network-forming and globular subtypes (n = 3). The upregulation of proliferation and differentiation genes in myofibroblasts seemed to be associated only with the fibrillar collagen subtype, whereas angiogenesis-related genes are associated with fibrillar, network-forming and multiplexin subtypes. In conclusion, although we intend for our findings to deepen the understanding of the mechanism of healing after myocardial infarction and scar formation, the process of collagen synthesis is highly complex, and further intensive investigation is needed to put together all the missing puzzle pieces in this still incipient knowledge process.


Assuntos
Infarto do Miocárdio , Humanos , Infarto do Miocárdio/metabolismo , Cicatriz/patologia , Colágeno/genética , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Miofibroblastos/metabolismo , Fibroblastos/metabolismo , Colágeno Tipo I/metabolismo , RNA Mensageiro/metabolismo , Miocárdio/metabolismo
6.
Int J Mol Sci ; 22(11)2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34067440

RESUMO

Myocardial infarction remains the most common cause of heart failure with adverse remodeling. MicroRNA (miR)155 is upregulated following myocardial infarction and represents a relevant regulatory factor for cardiac remodeling by engagement in cardiac inflammation, fibrosis and cardiomyocyte hypertrophy. Here, we investigated the role of miR155 in cardiac remodeling and dysfunction following myocardial infarction in a dyslipidemic mouse model. Myocardial infarction was induced in dyslipidemic apolipoprotein E-deficient (ApoE-/-) mice with and without additional miR155 knockout by ligation of the LAD. Four weeks later, echocardiography was performed to assess left ventricular (LV) dimensions and function, and mice were subsequently sacrificed for histological analysis. Echocardiography revealed no difference in LV ejection fractions, LV mass and LV volumes between ApoE-/- and ApoE-/-/miR155-/- mice. Histology confirmed comparable infarction size and unaltered neoangiogenesis in the myocardial scar. Notably, myofibroblast density was significantly decreased in ApoE-/-/miR155-/- mice compared to the control, but no difference was observed for total collagen deposition. Our findings reveal that genetic depletion of miR155 in a dyslipidemic mouse model of myocardial infarction does not reduce infarction size and consecutive heart failure but does decrease myofibroblast density in the post-ischemic scar.


Assuntos
MicroRNAs/genética , Infarto do Miocárdio/genética , Miofibroblastos/metabolismo , Função Ventricular Esquerda/genética , Animais , Modelos Animais de Doenças , Ecocardiografia/métodos , Fibrose/genética , Fibrose/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Ventrículos do Coração/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Volume Sistólico/genética , Remodelação Ventricular/genética
7.
Int J Mol Sci ; 22(18)2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34575848

RESUMO

ApoE abnormality represents a well-known risk factor for cardiovascular diseases. Beyond its role in lipid metabolism, novel studies demonstrate a complex involvement of apoE in membrane homeostasis and signaling as well as in nuclear transcription. Due to the large spread of apoE isoforms in the human population, there is a need to understand the apoE's role in pathological processes. Our study aims to dissect the involvement of apoE in heart failure. We showed that apoE-deficient rats present multiple organ damages (kidney, liver, lung and spleen) besides the known predisposition for obesity and affected lipid metabolism (two-fold increase in tissular damages in liver and one-fold increase in kidney, lung and spleen). Heart tissue also showed significant morphological changes in apoE-/- rats, mostly after a high-fat diet. Interestingly, the right ventricle of apoE-/- rats fed a high-fat diet showed more damage and affected collagen content (~60% less total collagen content and double increase in collagen1/collagen3 ratio) compared with the left ventricle (no significant differences in total collagen content or collagen1/collagen3 ratio). In patients, we were able to find a correlation between the presence of ε4 allele and cardiomyopathy (χ2 = 10.244; p = 0.001), but also with right ventricle dysfunction with decreased TAPSE (15.3 ± 2.63 mm in ε4-allele-presenting patients vs. 19.8 ± 3.58 mm if the ε4 allele is absent, p < 0.0001*) and increased in systolic pulmonary artery pressure (50.44 ± 16.47 mmHg in ε4-allele-presenting patients vs. 40.68 ± 15.94 mmHg if the ε4 allele is absent, p = 0.0019). Our results confirm that the presence of the ε4 allele is a lipid-metabolism-independent risk factor for heart failure. Moreover, we show for the first time that the presence of the ε4 allele is associated with right ventricle dysfunction, implying different regulatory mechanisms of fibroblasts and the extracellular matrix in both ventricles. This is essential to be considered and thoroughly investigated before the design of therapeutical strategies for patients with heart failure.


Assuntos
Apolipoproteína E4/genética , Cardiomiopatia Dilatada/etiologia , Cardiomiopatia Dilatada/fisiopatologia , Suscetibilidade a Doenças , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia , Alelos , Animais , Apolipoproteína E4/metabolismo , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/metabolismo , Dieta Hiperlipídica , Ecocardiografia , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Testes de Função Cardíaca , Humanos , Imuno-Histoquímica , Masculino , Mutação , Ratos , Disfunção Ventricular Direita/diagnóstico
8.
Int J Mol Sci ; 22(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33922385

RESUMO

Phosphatidylserines are known to sustain skeletal muscle activity during intense activity or hypoxic conditions, as well as preserve neurocognitive function in older patients. Our previous studies pointed out a potential cardioprotective role of phosphatidylserine in heart ischemia. Therefore, we investigated the effects of phosphatidylserine oral supplementation in a mouse model of acute myocardial infarction (AMI). We found out that phosphatidylserine increases, significantly, the cardiomyocyte survival by 50% in an acute model of myocardial ischemia-reperfusion. Similar, phosphatidylserine reduced significantly the infarcted size by 30% and improved heart function by 25% in a chronic model of AMI. The main responsible mechanism seems to be up-regulation of protein kinase C epsilon (PKC-ε), the main player of cardio-protection during pre-conditioning. Interestingly, if the phosphatidylserine supplementation is started before induction of AMI, but not after, it selectively inhibits neutrophil's activation, such as Interleukin 1 beta (IL-1ß) expression, without affecting the healing and fibrosis. Thus, phosphatidylserine supplementation may represent a simple way to activate a pre-conditioning mechanism and may be a promising novel strategy to reduce infarct size following AMI and to prevent myocardial injury during myocardial infarction or cardiac surgery. Due to the minimal adverse effects, further investigation in large animals or in human are soon possible to establish the exact role of phosphatidylserine in cardiac diseases.


Assuntos
Suplementos Nutricionais , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Fosfatidilserinas/farmacologia , Disfunção Ventricular Esquerda/complicações , Remodelação Ventricular/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/etiologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/efeitos dos fármacos , Disfunção Ventricular Esquerda/fisiopatologia , Remodelação Ventricular/fisiologia
9.
Int J Mol Sci ; 21(10)2020 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-32456225

RESUMO

AIM: Recruitment of neutrophils to the heart following acute myocardial infarction (MI) initiates inflammation and contributes to adverse post-infarct left ventricular (LV) remodeling. However, therapeutic inhibition of neutrophil recruitment into the infarct zone has not been beneficial in MI patients, suggesting a possible dual role for neutrophils in inflammation and repair following MI. Here, we investigate the effect of neutrophils on cardiac fibroblast function following MI. Methods and Results: We found that co-incubating neutrophils with isolated cardiac fibroblasts enhanced the production of provisional extracellular matrix proteins and reduced collagen synthesis when compared to control or co-incubation with mononuclear cells. Furthermore, we showed that neutrophils are required to induce the transient up-regulation of transforming growth factor (TGF)-ß1 expression in fibroblasts, a key requirement for terminating the pro-inflammatory phase and allowing the reparatory phase to form a mature scar after MI. Conclusion: Neutrophils are essential for both initiation and termination of inflammatory events that control and modulate the healing process after MI. Therefore, one should exercise caution when testing therapeutic strategies to inhibit neutrophil recruitment into the infarct zone in MI patients.


Assuntos
Infarto do Miocárdio/metabolismo , Miofibroblastos/metabolismo , Neutrófilos/metabolismo , Cicatrização , Animais , Comunicação Celular , Células Cultivadas , Técnicas de Cocultura/métodos , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/patologia , Fator de Crescimento Transformador beta/metabolismo
10.
BMC Genet ; 19(1): 112, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30545291

RESUMO

BACKGROUND: Fungal fruiting bodies are complex three-dimensional structures that are formed to protect and disperse the sexual spores. Their morphogenesis requires the concerted action of numerous genes; however, at the molecular level, the spatio-temporal sequence of events leading to the mature fruiting body is largely unknown. In previous studies, the transcription factor gene pro44 and the histone chaperone gene asf1 were shown to be essential for fruiting body formation in the ascomycete Sordaria macrospora. Both PRO44 and ASF1 are predicted to act on the regulation of gene expression in the nucleus, and mutants in both genes are blocked at the same stage of development. Thus, we hypothesized that PRO44 and ASF1 might be involved in similar aspects of transcriptional regulation. In this study, we characterized their roles in fruiting body development in more detail. RESULTS: The PRO44 protein forms homodimers, localizes to the nucleus, and is strongly expressed in the outer layers of the developing young fruiting body. Analysis of single and double mutants of asf1 and three other chromatin modifier genes, cac2, crc1, and rtt106, showed that only asf1 is essential for fruiting body formation whereas cac2 and rtt106 might have redundant functions in this process. RNA-seq analysis revealed distinct roles for asf1 and pro44 in sexual development, with asf1 acting as a suppressor of weakly expressed genes during morphogenesis. This is most likely not due to global mislocalization of nucleosomes as micrococcal nuclease-sequencing did not reveal differences in nucleosome spacing and positioning around transcriptional start sites between Δasf1 and the wild type. However, bisulfite sequencing revealed a decrease in DNA methylation in Δasf1, which might be a reason for the observed changes in gene expression. Transcriptome analysis of gene expression in young fruiting bodies showed that pro44 is required for correct expression of genes involved in extracellular metabolism. Deletion of the putative transcription factor gene asm2, which is downregulated in young fruiting bodies of Δpro44, results in defects during ascospore maturation. CONCLUSIONS: In summary, the results indicate distinct roles for the transcription factor PRO44 and the histone chaperone ASF1 in the regulation of sexual development in fungi.


Assuntos
Proteínas Fúngicas/genética , Chaperonas Moleculares/genética , Sordariales/genética , Fatores de Transcrição/genética , Núcleo Celular/metabolismo , Dimerização , Carpóforos/genética , Carpóforos/crescimento & desenvolvimento , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Chaperonas Moleculares/metabolismo , Mutagênese , RNA Fúngico/química , RNA Fúngico/genética , RNA Fúngico/metabolismo , Análise de Sequência de RNA , Sordariales/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
11.
Arch Toxicol ; 89(6): 823-50, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25820917

RESUMO

The advent of new testing systems and "omics"-technologies has left regulatory toxicology facing one of the biggest challenges for decades. That is the question whether and how these methods can be used for regulatory purposes. The new methods undoubtedly enable regulators to address important open questions of toxicology such as species-specific toxicity, mixture toxicity, low-dose effects, endocrine effects or nanotoxicology, while promising faster and more efficient toxicity testing with the use of less animals. Consequently, the respective assays, methods and testing strategies are subject of several research programs worldwide. On the other hand, the practical application of such tests for regulatory purposes is a matter of ongoing debate. This document summarizes key aspects of this debate in the light of the European "regulatory status quo", while elucidating new perspectives for regulatory toxicity testing.


Assuntos
Alternativas aos Testes com Animais/métodos , Testes de Toxicidade/métodos , Toxicologia/métodos , Alternativas aos Testes com Animais/legislação & jurisprudência , Animais , Europa (Continente) , Regulamentação Governamental , Humanos , Especificidade da Espécie , Testes de Toxicidade/normas , Testes de Toxicidade/tendências , Toxicologia/legislação & jurisprudência , Toxicologia/normas , Toxicologia/tendências , Estados Unidos
12.
J Environ Qual ; 43(3): 1004-12, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25602829

RESUMO

Proper assessments of lotic ecosystems depend on our ability to isolate natural differences from anthropogenic disturbances. We examined Nebraska river and stream classification strength, based on fish species, using multiple response permutation procedures for common classification strategies: ecoregions, watersheds, hydrologic-landscape regions, and assemblage structure from cluster analyses. Next, we tested the ecological interpretability of classification schemes using nonmetric multidimensional scaling ordinations and ANOVAs. Finally, we used nonparametric ANOVA to identify environmental predictors of overall fish assemblage structure. Hydrologic-landscape regions had the highest classification strength, but cluster groups had the most ecological interpretability based on the discreteness of the groups in ordination space and on the large number of common species that had different abundances across cluster groups. In addition, presence/absence data provided groups with more classification strength and interpretability than abundance data. Temperature, stream size, total phosphorus concentrations, and the percentage of fine substrates were significantly correlated to nonmetric multidimensional scaling ordinations and to overall fish structure in the multivariate ANOVA models. Cluster analyses using presence/absence were therefore the best classification scheme, and we identified the environmental variables that are likely to be useful for determining whether streams should have similar biotic assemblages. This information will be a valuable guide for separating natural variability in biotic assemblages from anthropogenic influences.

13.
Food Chem X ; 22: 101274, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38524778

RESUMO

The occurrence of persistent organic pollutants like polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in food represents a public health concern. The BfR MEAL Study was initiated to generate a comprehensive data base of occurrence data for chemicals in the most consumed foods in Germany. Non-dioxin-like PCBs (NDL-PCBs) and PBDEs were analysed in 300 foods, purchased and prepared representatively for the eating behaviour of the population in Germany. Highest levels of NDL-PCBs and PBDEs were detected in spiny dogfish, cod liver, herring, and eel. High NDL-PCB and PBDE levels were observed in other oily fish, wild boar meat, sheep liver, and high-fat dairy products. The comparison of food from conventional and organic production revealed higher NDL-PCB values in the food group 'meat and meat products' if produced organically. Occurrence data of this study will improve future dietary exposure and risk assessments in Germany.

14.
Anaesthesiologie ; 73(3): 168-176, 2024 03.
Artigo em Alemão | MEDLINE | ID: mdl-38334810

RESUMO

Aortic valve stenosis is a common condition that requires an anesthesiologist's in-depth knowledge of the pathophysiology, diagnostics and perioperative features of the disease. A newly diagnosed aortic valve stenosis is often initially identified from the anamnesis (dyspnea, syncope, angina pectoris) or a suspicious auscultation finding during the anesthesiologist's preoperative assessment. Interdisciplinary collaboration is essential to ensure the optimal management of these patients in the perioperative setting. An accurate anamnesis and examination during the preoperative assessment are crucial to select the most suitable anesthetic approach. Additionally, a precise understanding of the hemodynamic peculiarities associated with aortic valve stenosis is necessary. After a short summary of the overall pathophysiology of aortic valve stenosis, this review article focuses on the specific anesthetic considerations, risk factors for complications, and the perioperative management for noncardiac surgery in patients with aortic valve stenosis.


Assuntos
Anestesia , Anestésicos , Estenose da Valva Aórtica , Humanos , Estenose da Valva Aórtica/complicações , Fatores de Risco , Síncope/complicações
15.
Biomedicines ; 12(4)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38672230

RESUMO

BACKGROUND: Previous studies have shown cardiac abnormalities in acute liver injury, suggesting a potential role in the associated high mortality. METHODS: We designed an experimental study exploring the short-term effects of acute cholestasis-induced liver injury on cardiac function and structure in a rodent bile duct ligation (BDL) model to elucidate the potential interplay. Thirty-seven male Sprague-Dawley rats were subjected to BDL surgery (n = 28) or served as sham-operated (n = 9) controls. Transthoracic echocardiography, Doppler evaluation of the left anterior descending coronary artery, and myocardial contrast echocardiography were performed at rest and during adenosine and dobutamine stress 5 days after BDL. Immunohistochemical staining of myocardial tissue samples for hypoxia and inflammation as well as serum analysis were performed. RESULTS: BDL animals exhibited acute liver injury with elevated transaminases, bilirubin, and total circulating bile acids (TBA) 5 days after BDL (TBA control: 0.81 ± 2.54 µmol/L vs. BDL: 127.52 ± 57.03 µmol/L; p < 0.001). Concurrently, cardiac function was significantly impaired, characterized by reduced cardiac output (CO) and global longitudinal strain (GLS) in the echocardiography at rest and under pharmacological stress (CO rest control: 120.6 ± 24.3 mL/min vs. BDL 102.5 ± 16.6 mL/min, p = 0.041; GLS rest control: -24.05 ± 3.8% vs. BDL: -18.5 ± 5.1%, p = 0.01). Myocardial perfusion analysis revealed a reduced myocardial blood flow at rest and a decreased coronary flow velocity reserve (CFVR) under dobutamine stress in the BDL animals (CFVR control: 2.1 ± 0.6 vs. BDL: 1.7 ± 0.5 p = 0.047). Immunofluorescence staining indicated myocardial hypoxia and increased neutrophil infiltration. CONCLUSIONS: In summary, acute cholestasis-induced liver injury can lead to impaired cardiac function mediated by coronary microvascular dysfunction, suggesting that major adverse cardiac events may contribute to the mortality of acute liver failure. This may be due to endothelial dysfunction and direct bile acid signaling.

16.
Eur Radiol Exp ; 7(1): 6, 2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36757486

RESUMO

BACKGROUND: Coronary physiology assessment in rodents by ultrasound is an excellent noninvasive and easy to perform technique, including pulsed-wave Doppler (PWD) and myocardial contrast echocardiography (MCE). Both techniques and the corresponding calculated parameters were investigated in this study at rest as well as their response to pharmacologically induced stress. METHODS: Left ventricular myocardial function was assessed in eight anaesthetised rats using transthoracic echocardiography. Coronary physiology was assessed by both PWD of the left coronary artery and MCE using a bolus method. Measurements were performed at rest and under stimulation with adenosine and dobutamine. Effects of stimulation on the calculated parameters were evaluated and rated by effect size (η2). RESULTS: Changes could be demonstrated by selected parameters of PWD and MCE. The clearest effect in PWD was found for diastolic peak velocity (η2 = 0.58). It increased from 528 ± 110 mm/s (mean ± standard deviation) at rest to 839 ± 342 mm/s (p = 0.001) with adenosine and 1093 ± 302 mm/s with dobutamine (p = 0.001). The most distinct effect from MCE was found for the normalised wash-in rate (η2 = 0.58). It increased from 1.95 ± 0.35% at rest to 3.87 ± 0.85% with adenosine (p = 0.001) and 3.72 ± 1.03% with dobutamine (p = 0.001). CONCLUSION: Induced changes in coronary physiology by adenosine and dobutamine could successfully be monitored using MCE and PWD in anaesthetised rats. Due to the low invasiveness of the measurements, this protocol could be used for longitudinal animal studies.


Assuntos
Circulação Coronária , Dobutamina , Animais , Ratos , Dobutamina/farmacologia , Circulação Coronária/fisiologia , Ecocardiografia/métodos , Adenosina/farmacologia , Vasos Coronários/diagnóstico por imagem
17.
Rev Sci Instrum ; 94(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862508

RESUMO

A versatile multifunctional laboratory-based near ambient pressure x-ray photoelectron spectroscopy (XPS) instrument is presented. The entire device is highly customized regarding geometry, exchangeable manipulators and sample stages for liquid- and solid-state electrochemistry, cryochemistry, and heterogeneous catalysis. It therefore delivers novel and unique access to a variety of experimental approaches toward a broad choice of functional materials and their specific surface processes. The high-temperature (electro)catalysis manipulator is designed for probing solid state/gas phase interactions for heterogeneous catalysts including solid electrolyzer/fuel cell electrocatalysts at pressures up to 15 mbar and temperatures from room temperature to 1000 °C. The liquid electrochemistry manipulator is specifically designed for in situ spectroscopic investigations of polarized solid/liquid interfaces using aqueous electrolytes and the third one for experiments for ice and ice-like materials at cryogenic temperatures to approximately -190 °C. The flexible and modular combination of these setups provides the opportunity to address a broad spectrum of in situ and operando XPS experiments on a laboratory-based system, circumventing the limited accessibility of experiments at synchrotron facilities.

18.
Cell Rep ; 42(2): 112131, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36807143

RESUMO

Fibrosis represents the common end stage of chronic organ injury independent of the initial insult, destroying tissue architecture and driving organ failure. Here we discover a population of profibrotic macrophages marked by expression of Spp1, Fn1, and Arg1 (termed Spp1 macrophages), which expands after organ injury. Using an unbiased approach, we identify the chemokine (C-X-C motif) ligand 4 (CXCL4) to be among the top upregulated genes during profibrotic Spp1 macrophage differentiation. In vitro and in vivo studies show that loss of Cxcl4 abrogates profibrotic Spp1 macrophage differentiation and ameliorates fibrosis after both heart and kidney injury. Moreover, we find that platelets, the most abundant source of CXCL4 in vivo, drive profibrotic Spp1 macrophage differentiation. Single nuclear RNA sequencing with ligand-receptor interaction analysis reveals that macrophages orchestrate fibroblast activation via Spp1, Fn1, and Sema3 crosstalk. Finally, we confirm that Spp1 macrophages expand in both human chronic kidney disease and heart failure.


Assuntos
Macrófagos , Miofibroblastos , Humanos , Fibrose , Ligantes , Macrófagos/metabolismo , Miofibroblastos/metabolismo , Osteopontina , Fator Plaquetário 4/genética , Fator Plaquetário 4/metabolismo
19.
Discoveries (Craiova) ; 9(1): e122, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33969180

RESUMO

On December 31, 2019, the Wuhan Municipal Health Commission reported an increase in the incidence of pneumonia from an unknown cause. Shortly after, SARS-CoV-19 was identified as the responsible coronavirus for the heavy progress of the disease, which can manifest itself distinctively in different individuals. Coronavirus Disease 2019 (COVID-19) triggered a pandemic because of its high contagiousness before COVID-19 associated symptoms actually appear. In response to the rapid and continuous spread of the virus around the globe governments have mobilized their forces to restrict contact and thus avoid further infection and invested significant resources in treatment and prevention strategies to tackle COVID-19. As a result, US FDA and EMA have granted emergency use authorization for two mRNA-based vaccines, namely the vaccines developed by BioNTech/Pfizer and Moderna, for use in the USA and Europe. Due to the existing critical situation, the stages of vaccine development and testing have probably never been gone through so fast as at present. Here, we are briefly commenting on these two vaccines with their benefits, advantages and limitations.

20.
Food Chem ; 362: 130092, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34087715

RESUMO

Button mushrooms are widely produced edible basidiomycetes. Commercially, they are cultivated on substrates containing fermented horse manure and chicken feces. Since pharmacologically active substances (PAS) might be introduced into the food chain via animal treatment, their residues may be present in manure used for mushroom growth. Previous studies in plants have demonstrated an uptake of PAS from the agricultural environment. The present study was performed to investigate the presence of PAS in button mushrooms. For analysis, a multi-analyte method for the detection of 21 selected PAS using liquid chromatography tandem-mass spectrometry was developed, successfully validated and applied to commercially available button mushrooms. Traces of chloramphenicol were detected in two of 20 samples. Additionally, in a mushroom cultivation experiment an uptake of ciprofloxacin, chloramphenicol and praziquantel was conducted. Throughout the whole experiment, praziquantel was present in quantifiable amounts in mushrooms and in high quantities in soil.


Assuntos
Agaricus/química , Cloranfenicol/análise , Ciprofloxacina/análise , Praziquantel/análise , Agaricus/metabolismo , Agricultura , Animais , Galinhas , Cloranfenicol/metabolismo , Cromatografia Líquida , Ciprofloxacina/metabolismo , Análise de Alimentos , Cavalos , Praziquantel/metabolismo , Solo/química , Espectrometria de Massas em Tandem
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