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1.
Europace ; 25(1): 6-27, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35894842

RESUMO

Despite marked progress in the management of atrial fibrillation (AF), detecting AF remains difficult and AF-related complications cause unacceptable morbidity and mortality even on optimal current therapy. This document summarizes the key outcomes of the 8th AFNET/EHRA Consensus Conference of the Atrial Fibrillation NETwork (AFNET) and the European Heart Rhythm Association (EHRA). Eighty-three international experts met in Hamburg for 2 days in October 2021. Results of the interdisciplinary, hybrid discussions in breakout groups and the plenary based on recently published and unpublished observations are summarized in this consensus paper to support improved care for patients with AF by guiding prevention, individualized management, and research strategies. The main outcomes are (i) new evidence supports a simple, scalable, and pragmatic population-based AF screening pathway; (ii) rhythm management is evolving from therapy aimed at improving symptoms to an integrated domain in the prevention of AF-related outcomes, especially in patients with recently diagnosed AF; (iii) improved characterization of atrial cardiomyopathy may help to identify patients in need for therapy; (iv) standardized assessment of cognitive function in patients with AF could lead to improvement in patient outcomes; and (v) artificial intelligence (AI) can support all of the above aims, but requires advanced interdisciplinary knowledge and collaboration as well as a better medico-legal framework. Implementation of new evidence-based approaches to AF screening and rhythm management can improve outcomes in patients with AF. Additional benefits are possible with further efforts to identify and target atrial cardiomyopathy and cognitive impairment, which can be facilitated by AI.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/terapia , Inteligência Artificial , Diagnóstico Precoce , Consenso , Cognição , Acidente Vascular Cerebral/prevenção & controle
2.
J Chem Phys ; 157(18): 184112, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36379790

RESUMO

To accelerate the exploration of chemical space, it is necessary to identify the compounds that will provide the most additional information or value. A large-scale analysis of mononuclear octahedral transition metal complexes deposited in an experimental database confirms an under-representation of lower-symmetry complexes. From a set of around 1000 previously studied Fe(II) complexes, we show that the theoretical space of synthetically accessible complexes formed from the relatively small number of unique ligands is significantly (∼816k) larger. For the properties of these complexes, we validate the concept of ligand additivity by inferring heteroleptic properties from a stoichiometric combination of homoleptic complexes. An improved interpolation scheme that incorporates information about cis and trans isomer effects predicts the adiabatic spin-splitting energy to around 2 kcal/mol and the HOMO level to less than 0.2 eV. We demonstrate a multi-stage strategy to discover leads from the 816k Fe(II) complexes within a targeted property region. We carry out a coarse interpolation from homoleptic complexes that we refine over a subspace of ligands based on the likelihood of generating complexes with targeted properties. We validate our approach on nine new binary and ternary complexes predicted to be in a targeted zone of discovery, suggesting opportunities for efficient transition metal complex discovery.

3.
Exp Dermatol ; 30(12): 1814-1819, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34223669

RESUMO

Graft-versus-host disease (GvHD) is a major complication following stem-cell or solid-organ transplantation. Accurate diagnosis of cutaneous GvHD is challenging, given that drug eruptions and viral rashes may present with similar clinical/histological manifestations. Specific markers are not available. We performed the histological examination of biopsy samples from acute GvHD (aGvHD; n = 54), Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN; n = 27), maculopapular drug eruption (MDE; n = 26) and healthy controls (n = 26). Samples of aGvHD showed a decrease in Langerhans cells (LC, p = 0.0001) and an increase in macrophages (MΦ, p = 0.0001) compared to healthy skin. Compared to SJS/TEN, MDE and healthy skin, aGvHD biopsies contained greater numbers of CD4+ and CD8+ T cells. The majority of CD4+ T-helper cells were localized in the upper dermis, whereas cytotoxic CD8+ T cells were found in the epidermis. Increased numbers of CD56+ natural killer (NK) cells in the upper dermis of aGvHD skin (p = 0.007) were not observed in controls or SJS/TEN and MDE. There were no differences in elafin staining between aGvHD and the latter two conditions. Acute GvHD appears to have a distinct inflammatory cell profile (T cells/NK cells) that may aid establishing in a more accurate diagnosis, especially when used to rule out differential diagnoses such as SJS/TEN or MDE.


Assuntos
Doença Enxerto-Hospedeiro/diagnóstico , Transplante de Órgãos , Pele/patologia , Biomarcadores , Linfócitos T CD8-Positivos/metabolismo , Estudos de Casos e Controles , Diagnóstico Diferencial , Toxidermias/diagnóstico , Toxidermias/imunologia , Toxidermias/patologia , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Humanos , Células Matadoras Naturais/metabolismo , Síndrome de Stevens-Johnson/diagnóstico , Síndrome de Stevens-Johnson/imunologia
4.
J Chem Phys ; 152(8): 084112, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32113346

RESUMO

Locating the minimum energy structure of molecules, typically referred to as geometry optimization, is one of the first steps of any computational chemistry calculation. Earlier research was mostly dedicated to finding convenient sets of molecule-specific coordinates for a suitable representation of the potential energy surface, where a faster convergence toward the minimum structure can be achieved. More recent approaches, on the other hand, are based on various machine learning techniques and seem to revert to Cartesian coordinates instead for practical reasons. We show that the combination of Gaussian process regression with those coordinate systems employed by state-of-the-art geometry optimizers can significantly improve the performance of this powerful machine learning technique. This is demonstrated on a benchmark set of 30 small covalently bonded molecules.

5.
J Phys Chem A ; 123(18): 3977-3984, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-30973728

RESUMO

The 0.4 K internal temperature of superfluid helium nanodroplets is believed to guarantee a corresponding ground-state population of dopant atoms and molecules inside this cryogenic matrix. We have recorded 6s ← 5p excitation spectra of indium atoms in helium droplets and found two absorption bands separated by about 2000 cm-1, a value close to the spin-orbit (SO) splitting of the In 2P ground state. The intensities of the bands agree with a thermal population of the 2P1/2 and 2P3/2 states at 870 K, the temperature of the In pick-up cell. Applying femtosecond pump-probe spectroscopy, we found the same dynamical response of the helium solvation shell after the photoexcitation of the two bands. He-density functional theory simulations of the excitation spectra are in agreement with the bimodal structure. Our findings show that the population of SO levels of hot dopants is conserved after pick-up inside the superfluid droplet. Implications for the interpretation of experiments on molecular aggregates are discussed.

6.
Chemphyschem ; 19(18): 2331-2339, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-29863766

RESUMO

In a recent study [Angew. Chem. Int. Ed., 2014, 53, 9957-9960] a new concept of chiral separation has been suggested, which is based on functionalized, nanoporous sheets of graphene. In this follow-up article we discuss the underlying principle in greater detail and make suggestions for suitable pore functionalizations with respect to a selection of chiral prototype molecules. Considering drug molecules as future targets for a chiral separation via membranes, the necessary pore sizes represent a big challenge for standard methods of computational chemistry. Therefore, we test two common force fields (GAFF, CGenFF) as well as a semiempirical tight-binding approach recently developed by the Grimme group (GFN-xTB) against the computationally much more expensive density functional theory. We identify the GFN-xTB method as the most suitable approach for future simulations of functionalized pores for the given purpose, as it is able to produce reaction pathways in very good agreement with density functional theory, even in cases where force fields tend to an extreme overestimation of barrier heights.

7.
J Antimicrob Chemother ; 72(12): 3406-3413, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28961714

RESUMO

OBJECTIVES: A two-part (Phase 1B/3), sequential, open-label, multicentre study evaluated the pharmacokinetics (PK) and safety of intravenous (iv) posaconazole given as antifungal prophylaxis to neutropenic patients with AML or myelodysplastic syndrome (MDS) or to recipients at risk of invasive fungal disease (IFD) after allogeneic HSCT. METHODS: Patients (N = 237) received 300 mg of posaconazole iv twice daily on day 1, followed by 300 mg of posaconazole iv once daily for 4-28 days. After at least 5 days, patients were randomly assigned to receive posaconazole oral suspension, 400 mg twice daily or 200 mg three times daily, to complete a 28 day treatment course. Primary PK parameters were steady-state average concentration over the dosing interval (Cavg) and posaconazole trough levels (Cmin). RESULTS: Mean posaconazole Cmin was 1320 ng/mL (day 6) and 1297 ng/mL (day 8); steady-state Cmin was 1090 ng/mL (day 10). Mean steady-state posaconazole Cavg was 1500 ng/mL (day 10 or 14) and was similar in HSCT recipients (1560 ng/mL) and AML/MDS patients (1470 ng/mL). The most commonly reported treatment-related adverse events were diarrhoea (8%), nausea (5%) and rash (5%). IFD was reported in 3/237 patients (1%; 2 proven, 1 probable). CONCLUSIONS: Intravenous posaconazole at 300 mg was well tolerated, resulted in adequate steady-state systemic exposure and was associated with a low incidence of IFD in this population at high risk. TRIAL REGISTRY AND NUMBER: ClinicalTrials.gov, NCT01075984.


Assuntos
Antifúngicos/efeitos adversos , Antifúngicos/farmacocinética , Quimioprevenção/efeitos adversos , Quimioprevenção/métodos , Infecções Fúngicas Invasivas/prevenção & controle , Triazóis/efeitos adversos , Triazóis/farmacocinética , Administração Intravenosa , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/administração & dosagem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Hospedeiro Imunocomprometido , Leucemia Mieloide Aguda/complicações , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/complicações , Triazóis/administração & dosagem , Adulto Jovem
8.
Europace ; 18(1): 37-50, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26481149

RESUMO

At least 30 million people worldwide carry a diagnosis of atrial fibrillation (AF), and many more suffer from undiagnosed, subclinical, or 'silent' AF. Atrial fibrillation-related cardiovascular mortality and morbidity, including cardiovascular deaths, heart failure, stroke, and hospitalizations, remain unacceptably high, even when evidence-based therapies such as anticoagulation and rate control are used. Furthermore, it is still necessary to define how best to prevent AF, largely due to a lack of clinical measures that would allow identification of treatable causes of AF in any given patient. Hence, there are important unmet clinical and research needs in the evaluation and management of AF patients. The ensuing needs and opportunities for improving the quality of AF care were discussed during the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference in Nice, France, on 22 and 23 January 2015. Here, we report the outcome of this conference, with a focus on (i) learning from our 'neighbours' to improve AF care, (ii) patient-centred approaches to AF management, (iii) structured care of AF patients, (iv) improving the quality of AF treatment, and (v) personalization of AF management. This report ends with a list of priorities for research in AF patients.


Assuntos
Fibrilação Atrial/diagnóstico , Fibrilação Atrial/terapia , Cardiologia/normas , Procedimentos Clínicos/normas , Guias de Prática Clínica como Assunto , Melhoria de Qualidade/normas , Europa (Continente) , Humanos
9.
Br J Haematol ; 168(6): 824-34, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25546611

RESUMO

Salvage therapy followed by high-dose therapy (HDT) remains a mainstay for patients with relapsed lymphoma, however no optimal regimen has been defined. Here we report on the results of R-DexaBEAM (rituximab, dexamethasone, carmustine, etoposide, cytarabine, melphalan) followed by HDT. Patients aged 18-65 years, Eastern Cooperative Oncology Group performance score 0-2, with relapsed/refractory B-cell non-Hodgkin lymphoma (NHL) were eligible. R-Dexa-BEAM was given for two cycles followed by stem cell mobilization and HDT. Primary endpoint of the trial was progression-free-survival (PFS). One hundred and three patients were included: aggressive NHL (aNHL): diffuse large B-cell lymphoma 55, mantle cell lymphoma 7, follicular lymphoma (FL) grade 3: 5, indolent Lymphoma (iNHL): FL grade 1-2: 29, marginal zone lymphoma 6, Immunocytoma 1. The overall response rate after salvage therapy was 62% for aNHL and 78% for iNHL patients. 66% of patients with aNHL and 86% with iNHL underwent HDT. Treatment-related mortality for HDT was 1·3%. For aNHL patients, the median PFS was 0·83 years with 44% alive at the median follow-up of 7·3 years. Corresponding figures for iNHL were: median PFS 3·7 years and 72% alive after 8 years. The combination of rituximab with DexaBEAM followed by HDT resulted in high response rates and sustained remissions in responders. R-DexaBEAM followed by HDT can be considered a valid salvage option for NHL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Células B/tratamento farmacológico , Terapia de Salvação/métodos , Adulto , Idoso , Anticorpos Monoclonais Murinos/administração & dosagem , Anticorpos Monoclonais Murinos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carmustina/administração & dosagem , Carmustina/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Relação Dose-Resposta a Droga , Esquema de Medicação , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Mobilização de Células-Tronco Hematopoéticas/métodos , Humanos , Estimativa de Kaplan-Meier , Masculino , Melfalan/administração & dosagem , Melfalan/efeitos adversos , Pessoa de Meia-Idade , Seleção de Pacientes , Estudos Prospectivos , Recidiva , Indução de Remissão , Rituximab , Adulto Jovem
10.
Mol Carcinog ; 53(2): 117-24, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22930395

RESUMO

Recent studies of mammalian genomes suggest that alternative promoters are associated with various disorders, including cancer. Here we present an intronic promoter of the murine proteinase 3 gene, which drives the expression of an alternative mRNA in intron 2 of the prtn3 gene. The proximal promoter sequences were identified and a series of promoter deletion constructs were used to identify the sequence elements that are required for basal promoter activity. Expression of the homeobox transcription factor CUX1 p75 isoform was found to suppress the activity of the alternative PR3 promoter. Data base analyses, multiple alignments and expression data showed that the intronic PR3 promoter is active in leukemia and other tumor cells as well as in mouse embryo, male mammary gland and bone marrow. In the spleen, the transcript is exclusively expressed by Gr-1(int) /CD11b(+) cells, which are also known as myeloid-derived suppressor cells (MDSCs). In humans, an alternative transcript of the PR3-gene could be detected in the bone marrow and in various cancer cell lines but not in primary leukemia cells, suggesting a species-overarching function of this kind of promoter. Therefore, the alternative PR3 promoter and its mRNA may be useful tools to investigate the fate of hematopoietic stem cells.


Assuntos
Íntrons , Neoplasias/genética , RNA não Traduzido/genética , Animais , Sequência de Bases , Linhagem Celular , Linhagem Celular Tumoral , Genes Homeobox/genética , Células HL-60 , Células HeLa , Proteínas de Homeodomínio/genética , Humanos , Células MCF-7 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Mieloblastina/genética , Células NIH 3T3 , Regiões Promotoras Genéticas , Fatores de Transcrição/genética
11.
J Chromatogr A ; 1714: 464526, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38071876

RESUMO

Over the last years, inverse gas chromatography (IGC) proved to be a versatile and sensitive analytical technique for physicochemical properties. However, the comparability of results obtained by different users and devices remains a topic for debate. This is the first time, an interlaboratory study using different types of IGC instruments is reported. Eight organizations with different IGC devices defined a common lab measurement protocol to analyse two standard materials, silica and lactose. All data was collected in a standard result form and has been treated identically with the objective to identify experimentally observed differences and not potentially different data treatments. The calculated values of the dispersive surface energy vary quite significantly (silica: 22 mJ/m2 - 34 mJ/m2, lactose 37 mJ/m2 - 51 mJ/m2) and so do the ISP values and retention volumes for both materials. This points towards significant and seemingly undiscovered differences in the operation of the instruments and the obtained underlying primary data, even under the premise of standard conditions. Variations are independent of the instrument type and uncertainties in flow rates or the injected quantities of probe molecules may be potential factors for the differences. This interlaboratory study demonstrates that the IGC is a very sensitive analytical tool, which detects minor changes, but it also shows that for a proper comparison, the measurement conditions have to be checked with great care. A publicly available standard protocol and material, for which this study can be seen as a starting point, is still needed to judge on the measurements and the resulting parameters more objectively.


Assuntos
Lactose , Dióxido de Silício , Propriedades de Superfície , Lactose/química , Reprodutibilidade dos Testes , Cromatografia Gasosa/métodos
12.
Biol Blood Marrow Transplant ; 19(5): 767-76, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23376495

RESUMO

To assess current clinical practice in diagnosis and treatment of acute graft-versus-host disease (aGVHD), we performed a survey among German, Austrian, and Swiss allogeneic hematopoietic stem cell transplantation (allo-HSCT) centers. Thirty-four of 72 contacted centers (47%) completed both the diagnostic and therapeutic sections of the survey, representing 65% of allo-HSCT activity within the participating countries in 2011. Three pediatric centers answered as requested only the diagnostic part of the survey. In the presence of diarrhea and decreased oral intake after engraftment, only 4 centers (12%) do not perform any endoscopy before the start of immunosuppressive treatment. In case of a skin rash with the differential diagnosis of drug reaction, only 12 centers (35%) perform a skin biopsy up front, whereas 19 do so after failure of systemic steroids. In the presence of rapidly increasing cholestasis occurring without any other signs of aGVHD, 11 centers (32%) perform a liver biopsy up front and 14 only after failure of steroid treatment, whereas 9 centers do not perform a liver biopsy at all. Twenty centers (59%) use a percutaneous approach, 12 a transvenous approach, and 1 mini-laparoscopy for liver biopsies. First-line treatment of cutaneous aGVHD stage 1 consists of topical treatment alone in 17 of 31 responding centers (61%), whereas isolated cutaneous aGVHD stage III is treated with systemic steroids (prednisolone below 0.5 mg/kg/day n = 2, 0.5 to 1.0 mg/kg/day n = 10, above 1.0 to 2.5 mg/kg/day n = 19) without or with topical agents (steroids n = 10; calcineurin inhibitors n = 3). In gastrointestinal manifestations of aGVHD, 9 centers (29%) add topical to systemic steroids, and 3 consider topical steroids as the only treatment for mild gastrointestinal and cutaneous aGVHD. The choice of agent for second-line treatment as well as the sequence of administration are extremely heterogeneous, most likely due to a lack of convincing data published. Most frequently used are mycophenolate mofetil (n = 14) and extracorporeal photopheresis (n = 10). Our survey also demonstrates that clinicians chose salvage therapies for steroid-refractory aGVHD based on their centers' own clinical experience.


Assuntos
Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/terapia , Padrões de Prática Médica/estatística & dados numéricos , Doença Aguda , Áustria , Coleta de Dados , Alemanha , Doença Enxerto-Hospedeiro/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas/estatística & dados numéricos , Humanos , Suíça , Resultado do Tratamento
13.
Haematologica ; 98(4): 518-25, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22983588

RESUMO

Based on molecular aberrations, in particular the NPM1 mutation (NPM1(mut)) and the FLT3 internal tandem duplication (Flt3-ITD), prognostic subgroups have been defined among patients with acute myeloid leukemia with normal karyotype. Whereas these subgroups are known to play an important role in outcome in first complete remission, and also in the indication for allogeneic stem cell transplantation, data are limited on their role after transplantation in advanced disease. To evaluate the role of molecular subgroups of acute myeloid leukemia with normal karyotype after allogeneic stem cell transplantation beyond first complete remission, we analyzed the data from 141 consecutive adults (median age: 51.0 years, range 18.4-69.3 years) who had received an allogeneic transplant either in primary induction failure or beyond first complete remission. A sequential regimen of cytoreductive chemotherapy (fludarabine, high-dose AraC, amsacrine) followed by reduced intensity conditioning (FLAMSA-RIC), was uniformly used for conditioning. After a median follow up of three years, overall survival from transplantation was 64 ± 4%, 53 ± 4% and 44 ± 5% at one, two and four years, respectively. Forty patients transplanted in primary induction failure achieved an encouraging 2-year survival of 69%. Among 101 patients transplanted beyond first complete remission, 2-year survival was 81% among patients with the NPM1(mut)/FLT3(wt) genotype in contrast to 43% in other genotypes. Higher numbers of transfused CD34(+) cells (hazard ratio 2.155, 95% confidence interval 0.263-0.964, P=0.039) and favorable genotype (hazard ratio 0.142, 95% confidence interval: 0.19-0.898, P=0.048) were associated with superior overall survival in multivariate analysis. In conclusion, patients with acute myeloid leukemia with normal karyotype can frequently be rescued after primary induction failure by allogeneic transplantation following FLAMSA-RIC. The prognostic role of NPM1(mut)/FLT3-ITD based subgroups was carried through after allogeneic stem cell transplantation beyond first complete remission.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Quimioterapia de Indução/métodos , Leucemia Mieloide/genética , Leucemia Mieloide/terapia , Doença Aguda , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Cariótipo , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Mutação , Proteínas Nucleares/genética , Nucleofosmina , Recidiva , Terapia de Salvação/métodos , Condicionamento Pré-Transplante/métodos , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem , Tirosina Quinase 3 Semelhante a fms/genética
14.
Europace ; 15(11): 1540-56, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23981824

RESUMO

The management of atrial fibrillation (AF) has seen marked changes in past years, with the introduction of new oral anticoagulants, new antiarrhythmic drugs, and the emergence of catheter ablation as a common intervention for rhythm control. Furthermore, new technologies enhance our ability to detect AF. Most clinical management decisions in AF patients can be based on validated parameters that encompass type of presentation, clinical factors, electrocardiogram analysis, and cardiac imaging. Despite these advances, patients with AF are still at increased risk for death, stroke, heart failure, and hospitalizations. During the fourth Atrial Fibrillation competence NETwork/European Heart Rhythm Association (AFNET/EHRA) consensus conference, we identified the following opportunities to personalize management of AF in a better manner with a view to improve outcomes by integrating atrial morphology and damage, brain imaging, information on genetic predisposition, systemic or local inflammation, and markers for cardiac strain. Each of these promising avenues requires validation in the context of existing risk factors in patients. More importantly, a new taxonomy of AF may be needed based on the pathophysiological type of AF to allow personalized management of AF to come to full fruition. Continued translational research efforts are needed to personalize management of this prevalent disease in a better manner. All the efforts are expected to improve the management of patients with AF based on personalized therapy.


Assuntos
Fibrilação Atrial/terapia , Gerenciamento Clínico , Medicina de Precisão/métodos , Medicina de Precisão/tendências , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/genética , Biomarcadores/sangue , Encéfalo/patologia , Ecocardiografia , Eletrocardiografia , Humanos , Imageamento por Ressonância Magnética , Fatores de Risco , Resultado do Tratamento
15.
J Immunol ; 187(3): 1142-9, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21697461

RESUMO

Epidermal Langerhans cells (LC) are potent APCs surveying the skin. They are crucial regulators of T cell activation in the context of inflammatory skin disease and graft-versus-host disease (GVHD). In contrast to other dendritic cell subtypes, murine LC are able to reconstitute after local depletion without the need of peripheral blood-derived precursors. In this study, we introduce an experimental model of human skin grafted to NOD-SCID IL2Rγ(null) mice. In this model, we demonstrate that xenografting leads to the transient loss of LC from the human skin grafts. Despite the lack of a human hematopoietic system, human LC repopulated the xenografts 6 to 9 wk after transplantation. By staining of LC with the proliferation marker Ki67, we show that one third of the replenishing LC exhibit proliferative activity in vivo. We further used the skin xenograft as an in vivo model for human GVHD. HLA-disparate third-party T cells stimulated with skin donor-derived dendritic cells were injected intravenously into NOD-SCID IL2Rγ(null) mice that had been transplanted with human skin. The application of alloreactive T cells led to erythema and was associated with histological signs of GVHD limited to the transplanted human skin. The inflammation also led to the depletion of LC from the epidermis. In summary, we provide evidence that human LC are able to repopulate the skin independent of blood-derived precursor cells and that this at least partly relates to their proliferative capacity. Our data also propose xeno-transplantation of human skin as a model system for studying the role of skin dendritic cells in the efferent arm of GVHD.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Epiderme/imunologia , Células de Langerhans/imunologia , Ativação Linfocitária/imunologia , Transplante de Pele/imunologia , Transplante Heterólogo/imunologia , Animais , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/transplante , Morte Celular/imunologia , Morte Celular/efeitos da radiação , Diferenciação Celular/imunologia , Diferenciação Celular/efeitos da radiação , Movimento Celular/imunologia , Movimento Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Células Cultivadas , Modelos Animais de Doenças , Epiderme/patologia , Epiderme/transplante , Feminino , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Humanos , Células de Langerhans/patologia , Células de Langerhans/transplante , Ativação Linfocitária/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Camundongos Transgênicos , Transplante de Pele/patologia , Transplante Heterólogo/patologia
16.
Beilstein J Nanotechnol ; 14: 586-602, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37228743

RESUMO

The thermal conductance of nanowires is an oft-explored quantity, but its dependence on the nanowire shape is not completely understood. The behaviour of the conductance is examined as kinks of varying angular intensity are included into nanowires. The effects on thermal transport are evaluated through molecular dynamics simulations, phonon Monte Carlo simulations and classical solutions of the Fourier equation. A detailed look is taken at the nature of heat flux within said systems. The effects of the kink angle are found to be complex, influenced by multiple factors including crystal orientation, details of transport modelling, and the ratio of mean free path to characteristic system lengths. The effect of varying phonon reflection specularity on the heat flux is also examined. It is found that, in general, the flow of heat through systems simulated through phonon Monte Carlo methods is concentrated into a channel smaller than the wire dimensions, while this is not the case in the classical solutions of the Fourier model.

17.
Front Chem ; 11: 1084046, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37065825

RESUMO

Surface-modified porous silica is a well-established composite material. To improve its embedding and application behavior, adsorption studies of various probe molecules have been performed using the technique of inverse gas chromatography (IGC). For this purpose, IGC experiments were carried out in the infinite dilution mode on macro-porous micro glass spheres before and after surface modification with (3-mercaptopropyl)trimethoxysilane. To provide information about the polar interactions between probe molecules and the silica surface, in particular, eleven polar molecules have been injected. In summary, the free surface energy for pristine silica ( γ S t o t a l = 229 mJ/m2) and for (3-mercaptopropyl)trimethoxysilane-modified silica ( γ S t o t a l = 135 mJ/m2) indicates a reduced wettability after surface modification. This is due to the reduction of the polar component of the free surface energy ( γ S S P ) from 191 mJ/m2 to 105 mJ/m2. Simultaneously, with the reduction of surface silanol groups caused by surface modification of silica and, therefore, the decrease in polar interactions, a substantial loss of Lewis acidity was observed by various IGC approaches. Experiments with all silica materials have been conducted at temperatures in the range from 90°C to 120°C to determine the thermodynamic parameters, such as adsorption enthalpy ( Δ H a d s ) and adsorption entropy ( Δ S a d s ), using the Arrhenius regression procedure evaluating the IGC data. With the help of the enthalpy-entropy compensation, two types of adsorption complexes are assumed between polar probe molecules and the silica surface because of different isokinetic temperatures. Identical adsorption complexes with an isokinetic temperature of 370°C have been assigned to alkanes and weakly interacting polar probes such as benzene, toluene, dichloromethane, and chloroform. Polar probe molecules with typical functional groups such as OH, CO, and CN, having the ability to form hydrogen bonds to the silica surface, exhibit a lower isokinetic temperature of 60°C. Quantum chemical calculations of the probe molecules on a non-hydroxylated and hydroxylated silica cluster supported the formation of hydrogen bonds in the case of a strong polar adsorption complex with a bonding distance of 1.7 nm-1.9 nm to the silica surface.

18.
Nat Comput Sci ; 3(1): 38-47, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38177951

RESUMO

Approximate density functional theory has become indispensable owing to its balanced cost-accuracy trade-off, including in large-scale screening. To date, however, no density functional approximation (DFA) with universal accuracy has been identified, leading to uncertainty in the quality of data generated from density functional theory. With electron density fitting and Δ-learning, we build a DFA recommender that selects the DFA with the lowest expected error with respect to the gold standard (but cost-prohibitive) coupled cluster theory in a system-specific manner. We demonstrate this recommender approach on the evaluation of vertical spin splitting energies of transition metal complexes. Our recommender predicts top-performing DFAs and yields excellent accuracy (about 2 kcal mol-1) for chemical discovery, outperforming both individual Δ-learning models and the best conventional single-functional approach from a set of 48 DFAs. By demonstrating transferability to diverse synthesized compounds, our recommender potentially addresses the accuracy versus scope dilemma broadly encountered in computational chemistry.

19.
Stud Health Technol Inform ; 307: 161-171, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37697850

RESUMO

Representing knowledge in a comprehensible and maintainable way and transparently providing inferences thereof are important issues, especially in the context of applications related to artificial intelligence in medicine. This becomes even more obvious if the knowledge is dynamically growing and changing and when machine learning techniques are being involved. In this paper, we present an approach for representing knowledge about cancer therapies collected over two decades at St.-Johannes-Hospital in Dortmund, Germany. The presented approach makes use of InteKRator, a toolbox that combines knowledge representation and machine learning techniques, including the possibility of explaining inferences. An extended use of InteKRator's reasoning system will be introduced for being able to provide the required inferences. The presented approach is general enough to be transferred to other data, as well as to other domains. The approach will be evaluated, e. g., regarding comprehensibility, accuracy and reasoning efficiency.


Assuntos
Medicina , Neoplasias , Humanos , Inteligência Artificial , Neoplasias/terapia , Alemanha , Hospitais
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