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1.
Rep Prog Phys ; 87(3)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38241725

RESUMO

For decades, frustrated quantum magnets have been a seed for scientific progress and innovation in condensed matter. As much as the numerical tools for low-dimensional quantum magnetism have thrived and improved in recent years due to breakthroughs inspired by quantum information and quantum computation, higher-dimensional quantum magnetism can be considered as the final frontier, where strong quantum entanglement, multiple ordering channels, and manifold ways of paramagnetism culminate. At the same time, efforts in crystal synthesis have induced a significant increase in the number of tangible frustrated magnets which are generically three-dimensional in nature, creating an urgent need for quantitative theoretical modeling. We review the pseudo-fermion (PF) and pseudo-Majorana (PM) functional renormalization group (FRG) and their specific ability to address higher-dimensional frustrated quantum magnetism. First developed more than a decade ago, the PFFRG interprets a Heisenberg model Hamiltonian in terms of Abrikosov pseudofermions, which is then treated in a diagrammatic resummation scheme formulated as a renormalization group flow ofm-particle pseudofermion vertices. The article reviews the state of the art of PFFRG and PMFRG and discusses their application to exemplary domains of frustrated magnetism, but most importantly, it makes the algorithmic and implementation details of these methods accessible to everyone. By thus lowering the entry barrier to their application, we hope that this review will contribute towards establishing PFFRG and PMFRG as the numerical methods for addressing frustrated quantum magnetism in higher spatial dimensions.

2.
Gastroenterology ; 164(1): 72-88.e18, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36108710

RESUMO

BACKGROUND & AIMS: Single-agent anti-PD1 checkpoint inhibitors convey outstanding clinical benefits in a small fraction (∼20%) of patients with advanced hepatocellular carcinoma (aHCC) but the molecular mechanisms determining response are unknown. To fill this gap, we herein analyze the molecular and immune traits of aHCC in patients treated with anti-PD1. METHODS: Overall, 111 tumor samples from patients with aHCC were obtained from 13 centers before systemic therapies. We performed molecular analysis and immune deconvolution using whole-genome expression data (n = 83), mutational analysis (n = 72), and histologic evaluation with an endpoint of objective response. RESULTS: Among 83 patients with transcriptomic data, 28 were treated in frontline, whereas 55 patients were treated after tyrosine kinase inhibitors (TKI) either in second or third line. Responders treated in frontline showed upregulated interferon-γ signaling and major histocompatibility complex II-related antigen presentation. We generated an 11-gene signature (IFNAP), capturing these molecular features, which predicts response and survival in patients treated with anti-PD1 in frontline. The signature was validated in a separate cohort of aHCC and >240 patients with other solid cancer types where it also predicted response and survival. Of note, the same signature was unable to predict response in archival tissue of patients treated with frontline TKIs, highlighting the need for fresh biopsies before immunotherapy. CONCLUSION: Interferon signaling and major histocompatibility complex-related genes are key molecular features of HCCs responding to anti-PD1. A novel 11-gene signature predicts response in frontline aHCC, but not in patients pretreated with TKIs. These results must be confirmed in prospective studies and highlights the need for biopsies before immunotherapy to identify biomarkers of response.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Estudos Prospectivos , Biomarcadores
3.
New Phytol ; 244(1): 192-201, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39107894

RESUMO

The devastating pathogen Botrytis cinerea infects a broad spectrum of host plants, causing great socio-economic losses. The necrotrophic fungus rapidly kills plant cells, nourishing their wall and cellular contents. To this end, necrotrophs secrete a cocktail of cell wall degrading enzymes, phytotoxic proteins and metabolites. Additionally, many fungi produce specialized invasion organs that generate high invasive pressures to force their way into the plant cell. However, for most necrotrophs, including Botrytis, the biomechanics of penetration and its contribution to virulence are poorly understood. Here, we use a combination of quantitative micromechanical imaging and CRISPR-Cas-guided mutagenesis to show that Botrytis uses substantial invasive pressure, in combination with strong surface adherence, for penetration. We found that the fungus establishes a unique mechanical geometry of penetration that develops over time during penetration events, and which is actin cytoskeleton dependent. Furthermore, interference of force generation by blocking actin polymerization was found to decrease Botrytis virulence, indicating that also for necrotrophs, mechanical pressure is important in host colonization. Our results demonstrate for the first time mechanistically how a necrotrophic fungus such as Botrytis employs this 'brute force' approach, in addition to the secretion of lytic proteins and phytotoxic metabolites, to overcome plant host resistance.


Assuntos
Actinas , Botrytis , Doenças das Plantas , Pressão , Botrytis/patogenicidade , Botrytis/fisiologia , Doenças das Plantas/microbiologia , Actinas/metabolismo , Virulência , Fenômenos Biomecânicos
4.
Hepatology ; 78(6): 1882-1895, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37334496

RESUMO

BACKGROUND AND AIMS: Chronic HEV infections remain a serious problem in immunocompromised patients, as specifically approved antiviral drugs are unavailable. In 2020, a 24-week multicenter phase II pilot trial was carried out, evaluating the nucleotide analog sofosbuvir by treating nine chronically HEV-infected patients with sofosbuvir (Trial Number NCT03282474). During the study, antiviral therapy reduced virus RNA levels initially but did not lead to a sustained virologic response. Here, we characterize the changes in HEV intrahost populations during sofosbuvir treatment to identify the emergence of treatment-associated variants. APPROACH AND RESULTS: We performed high-throughput sequencing on RNA-dependent RNA polymerase sequences to characterize viral population dynamics in study participants. Subsequently, we used an HEV-based reporter replicon system to investigate sofosbuvir sensitivity in high-frequency variants. Most patients had heterogenous HEV populations, suggesting high adaptability to treatment-related selection pressures. We identified numerous amino acid alterations emerging during treatment and found that the EC 50 of patient-derived replicon constructs was up to ~12-fold higher than the wild-type control, suggesting that variants associated with lower drug sensitivity were selected during sofosbuvir treatment. In particular, a single amino acid substitution (A1343V) in the finger domain of ORF1 could reduce susceptibility to sofosbuvir significantly in 8 of 9 patients. CONCLUSIONS: In conclusion, viral population dynamics played a critical role during antiviral treatment. High population diversity during sofosbuvir treatment led to the selection of variants (especially A1343V) with lower sensitivity to the drug, uncovering a novel mechanism of resistance-associated variants during sofosbuvir treatment.


Assuntos
Hepatite E , Sofosbuvir , Humanos , Sofosbuvir/farmacologia , Sofosbuvir/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , Hepatite E/tratamento farmacológico , Resposta Viral Sustentada , Quimioterapia Combinada , Hepacivirus/genética , Genótipo , Resultado do Tratamento
5.
J Exp Bot ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38628155

RESUMO

Optimal stomatal regulation is important for plant adaptation to changing environmental conditions and for maintaining crop yield. The guard-cell signal GABA is produced from glutamate by Glutamate Decarboxylase (GAD) during a reaction that generates carbon dioxide (CO2) as a by-product. Here, we investigated a putative connection between GABA signalling and the more clearly defined CO2 signalling pathway in guard cells. The GABA-deficient mutant lines gad2-1, gad2-2 and gad1/2/4/5 were examined for stomatal sensitivity to various CO2 concentrations. Our findings show a phenotypical discrepancy between the allelic mutant lines gad2-1 and gad2-2 - a weakened CO2 response in gad2-1 (GABI_474_E05) in contrast to a wild-type response in gad2-2 (SALK_028819) and gad1/2/4/5. Through transcriptomic and genomic investigation, we traced the response of gad2-1 to a deletion of full-length Mitogen-activated protein kinase 12 (MPK12) in the GABI-KAT line, thereafter as renamed gad2-1*. Guard cell-specific complementation of MPK12 restored the gad2-1* CO2 phenotype, which confirms the proposed importance of MPK12 to CO2 sensitivity. Additionally, we found that stomatal opening under low atmospheric CO2 occurs independently of the GABA-modulated opening-channel ALMT9. Our results confirm that GABA has a role in modulating the rate of stomatal opening and closing - but not in response to CO2  per se.

6.
Z Gastroenterol ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227008

RESUMO

Real-world data on the management of patients with primary biliary cholangitis (PBC) are so far scarce in Germany. Therefore, we aimed to establish a nationwide registry and describe the clinical characteristics and therapy of PBC patients.Three different cohorts defined as ursodeoxycholic acid (UDCA) responders, as inadequate responders according to Paris II criteria, and as newly diagnosed patients were prospectively recruited.This manuscript includes the baseline data of the project.In total, 33/77 (43%) contacted centres (58% of university hospitals, 38% of non-university hospitals, and 24% of private practices) recruited 515 patients including 204 UDCA responders, 221 inadequate responders to UDCA, and 90 newly diagnosed patients.All patients were treated with UDCA; however, a UDCA dosage below the recommended dosage of 13 mg/kg/d was observed in 38.5% of individuals after 12 months of treatment. UDCA dosages were lower in nonacademic compared to academic centres.Only 75/219 (38.5%) of inadequate responders to UDCA received a second-line therapy with obeticholic acid (OCA) and/or bezafibrate (BZF). OCA (13% vs. 4.5%) and BZF (14% vs. 6.5%) were significantly more often prescribed by academic vs. nonacademic centres.Pruritus (27% vs. 15.5%), fatigue (23% vs. 4.5%), and sicca syndrome (14% vs. 1%) were significantly more often reported by academic centres.The German PBC registry could be established, which indicates suboptimal therapy in a relevant proportion of patients and shows significant differences between academic and nonacademic centres. Results are fundamental to improving clinical management at different levels of care.

7.
Bioprocess Biosyst Eng ; 47(5): 713-724, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38627303

RESUMO

The concept of modular synthetic co-cultures holds considerable potential for biomanufacturing, primarily to reduce the metabolic burden of individual strains by sharing tasks among consortium members. However, current consortia often show unilateral relationships solely, without stabilizing feedback control mechanisms, and are grown in a shared cultivation setting. Such 'one pot' approaches hardly install optimum growth and production conditions for the individual partners. Hence, novel mutualistic, self-coordinating consortia are needed that are cultured under optimal growth and production conditions for each member. The heterologous production of the antibiotic violacein (VIO) in the mutually interacting E. coli-E. coli consortium serves as an example of this new principle. Interdependencies for growth control were implemented via auxotrophies for L-tryptophan and anthranilate (ANT) that were satisfied by the respective partner. Furthermore, VIO production was installed in the ANT auxotrophic strain. VIO production, however, requires low temperatures of 20-30 °C which conflicts with the optimum growth temperature of E. coli at 37 °C. Consequently, a two-compartment, two-temperature level setup was used, retaining the mutual interaction of the cells via the filter membrane-based exchange of medium. This configuration also provided the flexibility to perform individualized batch and fed-batch strategies for each co-culture member. We achieved maximum biomass-specific productivities of around 6 mg (g h)-1 at 25 °C which holds great promise for future applications.


Assuntos
Reatores Biológicos , Técnicas de Cocultura , Escherichia coli , Indóis , Escherichia coli/metabolismo , Escherichia coli/crescimento & desenvolvimento , Indóis/metabolismo
8.
Pneumologie ; 2024 Aug 15.
Artigo em Alemão | MEDLINE | ID: mdl-39146969

RESUMO

Some of the patients with SARS-CoV-2 infection (COVID-19) received invasive ventilation during inpatient care. Weaning from ventilation was difficult for some patients (so-called prolonged weaning). PATIENTS: Patients (n=751) with prolonged weaning (reason for ventilation "pneumonia" and "acute respiratory failure") from four centers for the period 2011-23 from the "WeanNet" registry were used as a matched group. RESULTS: The median duration of intensive medical care was 39 (25-68) days. In 19% (37/193) of patients, ECMO support was necessary for a median of 27 (18-51) days. In-hospital mortality was 8.3% (2.7% with vs. 9.6% without ECMO) and 6.8% died in the comparison group. At discharge, 84% (vs. 77% in the control group) were completely weaned and 2.6% (vs. 17.6% in the control group) of patients received non-invasive treatment. Invasive ventilation was still necessary in 7.8% (control group 15.7%). In the observation period of 6 months after discharge, 22.4% of patients required inpatient care and a further 14.1% after 12 months. The overall mortality at 12-month follow-up was 20,6% (5.6% with vs. 24.6% without ECMO). DISCUSSION: The mortality rate of ventilated patients with COVID-19 was very low at 8.3% in the four weaning centers studied. The mortality rate of patients with ECMO treatment was only 2.7%. The mortality rate in the control group was 7.3%. The lower mortality of patients with ECMO treatment was also evident at follow-up of up to 12 months.Patients with prolonged weaning who received invasive ventilation due to COVID-19 showed comparable results in terms of successful weaning and mortality compared to a control group from the WeanNet registry. The long-term results with a survival of more than 80% for the first year after discharge were encouraging.

9.
J Hepatol ; 78(1): 57-66, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36031158

RESUMO

BACKGROUND & AIMS: Data on the long-term persistence of HCV resistance-associated substitutions (RASs) after treatment with direct-acting antivirals (DAAs) are limited. This study evaluated the persistence of NS3, NS5A, and NS5B RASs for up to 5 years after the end of treatment (EOT). METHODS: We included samples from 678 individuals with an HCV genotype (GT) 1 or 3 infection and virologic DAA treatment failure collected in the European Resistance Database. NS3, NS5A, and NS5B were sequenced, and clinical parameters were evaluated. RESULTS: A total of 242 individuals with HCV GT1a (36%), 237 with GT1b (35%), and 199 (29%) with GT3 and a DAA failure were included. After protease inhibitor failure, the frequencies of NS3 RASs were 40-90% after the EOT. NS3 RASs disappeared rapidly in GT1b and GT3 after follow-up month 3 but were stable (≥60%) in GT1a owing to Q80K. The SOF-resistant NS5B RAS S282T was only found in individuals with GT3a. Non-nucleoside NS5B RASs were frequent in GT1 (56-80%) and decreased to 30% in GT1a but persisted in GT1b. NS5A RASs were very common in all GTs after NS5A inhibitor failure (88-95%), and even after follow-up month 24, their frequency was 65% and higher. However, RASs in GT1b had a stable course, whereas RASs in GT1a and GT3 declined slightly after follow-up month 24 (GT1a, 68%; GT1b, 95%; and GT3, 65%), mainly because of the slow decline of high-level resistant Y93H. CONCLUSIONS: We found that low-to medium-level RASs persisted, whereas high-level resistant RASs disappeared over time. Different patterns of RAS persistence according to HCV subtype could have implications for retreatment with first-generation DAAs and for global HCV elimination goals. IMPACT AND IMPLICATIONS: There are little data on the long-term persistence of HCV resistance-associated substitutions (RASs) after DAA treatment failure, and RASs could have an impact on the efficacy of a rescue treatment. Especially in countries with limited availability of VOX/VEL/SOF or G/P/SOF, different patterns of RAS persistence could have implications for retreatment with first-generation DAAs and for global HCV elimination goals. The different patterns of RAS persistence identified in this study can be used to derive general rules regarding the persistence of RASs after DAA failure that could be applied by physicians in less developed countries to plan individualized HCV retreatment.


Assuntos
Antivirais , Hepatite C Crônica , Humanos , Antivirais/farmacologia , Antivirais/uso terapêutico , Farmacorresistência Viral/genética , Proteínas não Estruturais Virais/genética , Genótipo , Hepatite C Crônica/tratamento farmacológico , Hepacivirus/genética , Falha de Tratamento
10.
BMC Immunol ; 24(1): 11, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37353774

RESUMO

BACKGROUND: Elevated levels of extracellular adenosine triphosphate (ATP) modulate immunologic pathways and are considered to be a danger signal in inflammation, lung fibrosis and cancer. Macrophages can be classified into two main types: M1 macrophages are classically activated, pro-inflammatory macrophages, whereas M2 macrophages are alternatively activated, pro-fibrotic macrophages. In this study, we examined the effect of ATP on differentiation of native human monocytes into these macrophage subtypes. We characterized M1 and M2 like macrophages by their release of Interleukin-1beta (IL-1ß) and Chemokine (C-C motif) ligand 18 (CCL18), respectively. RESULTS: Monocytes were stimulated with ATP or the P2X7 receptor agonist Benzoylbenzoyl-ATP (Bz-ATP), and the production of various cytokines was analyzed, with a particular focus on CCL18 and IL-1ß, along with the expression of different purinergic receptors. Over a 72 h period of cell culture, monocytes spontaneously differentiated to M2 like macrophages, as indicated by an increased release of CCL18. Immediate stimulation of monocytes with ATP resulted in a dose-dependent reduction in CCL18 release, but had no effect on the concentration of IL-1ß. In contrast, delayed stimulation with ATP had no effect on either CCL18 or IL-1ß release. Similar results were observed in a model of inflammation using lipopolysaccharide-stimulated human monocytes. Stimulation with the P2X7 receptor agonist Bz-ATP mimicked the effect of ATP on M2-macrophage differentiation, indicating that P2X7 is involved in ATP-induced inhibition of CCL18 release. Indeed, P2X7 was downregulated during spontaneous M2 differentiation, which may partially explain the ineffectiveness of late ATP stimulation of monocytes. However, pre-incubation of monocytes with PPADS, Suramin (unselective P2X- and P2Y-receptor blockers) and KN62 (P2X7-antagonist) failed to reverse the reduction of CCL18 by ATP. CONCLUSIONS: ATP prevents spontaneous differentiation of monocytes into M2-like macrophages in a dose- and time-dependent manner. These effects were not mediated by P2X and P2Y receptors.


Assuntos
Monócitos , Receptores Purinérgicos P2X7 , Humanos , Macrófagos , Diferenciação Celular , Trifosfato de Adenosina , Inflamação , Células Cultivadas
11.
Eur Radiol ; 33(9): 5933-5942, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37052657

RESUMO

OBJECTIVES: Bile leakage (BL) is a challenging complication after hepatobiliary surgery and liver trauma. Gadolinium ethoxybenzyl (Gd-EOB-DTPA)-enhanced magnetic resonance cholangiopancreatography (MRCP) is used to diagnose BL non-invasively. We assessed the value of Gd-EOB-DTPA-MRCP in the detection of postoperative and post-traumatic BL hypothesizing that exact identification of the leakage site is pivotal for treatment planning and outcome. METHODS: We retrospectively enrolled 39 trauma and postoperative patients who underwent Gd-EOB-DTPA-MRCP for suspected BL. Three readers rated the presence of BL and leakage site (intraparenchymal, central, peripheral ± aberrant or disconnected ducts). Imaging findings were compared to subsequent interventional procedures and their complexity and outcome. RESULTS: BL was detected in Gd-EOB-DTPA-MRCP in 25 of patients and was subsequently confirmed. Sites of BL differed significantly between postoperative (central [58%] and peripheral [42%]) and trauma patients (intraparenchymal [100%]; p < 0.001). Aberrant or disconnected ducts were diagnosed in 8%/26% of cases in the postoperative subgroup. Inter-rater agreement for the detection and localization of BL was almost perfect (Κ = 0.85 and 0.88; p < 0.001). Intraparenchymal BL required significantly less complex interventional procedures (p = 0.002), whereas hospitalization and mortality did not differ between the subgroups (p > 0.05). CONCLUSIONS: Gd-EOB-DTPA-MRCP reliably detects and exactly locates BL in postoperative and trauma patients. Exact localization of biliary injuries enables specific treatment planning, as intraparenchymal leakages, which occur more frequently after trauma, require less complex interventions than central or peripheral leaks in the postoperative setting. As a result of specific treatment based on exact BL localization, there was no difference in the duration of hospitalization or mortality. CLINICAL RELEVANCE STATEMENT: Gd-EOB-DTPA-MRCP is a reliable diagnostic tool for exactly localizing iatrogenic and post-traumatic biliary leakage. Its precise localization helps tailor local therapies for different injury patterns, resulting in comparable clinical outcomes despite varying treatments. KEY POINTS: • Gd-EOB-DTPA-MRCP enables adequate detection and localization of bile leakages in both postoperative and post-traumatic patients. • The site of bile leakage significantly impacts the complexity of required additional interventions. • Intraparenchymal bile leakage is commonly seen in patients with a history of liver trauma and requires less complex interventions than postoperative central or peripheral bile leakages, while hospitalization and mortality are similar.


Assuntos
Doenças Biliares , Neoplasias Hepáticas , Humanos , Colangiopancreatografia por Ressonância Magnética/métodos , Meios de Contraste , Estudos Retrospectivos , Bile , Gadolínio DTPA , Fígado/diagnóstico por imagem , Fígado/cirurgia , Fígado/patologia , Resultado do Tratamento , Imageamento por Ressonância Magnética/métodos
12.
Hepatol Res ; 53(12): 1156-1168, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37565510

RESUMO

AIM: Interleukin (IL)-10 and IL-12 contribute to immune responses against hepatitis B virus (HBV) infection. Polymorphisms in the IL-10 and IL-12A genes might affect the clinical outcome of HBV infection. We evaluated the association of IL-10 rs1800896 and rs3024490, and IL-12A rs568408 and rs2243115 with the progression of HBV infection and development of severe liver disease stages in a white European population. METHOD: A total of 636 white European patients with chronic HBV infection, 239 individuals with spontaneous HBV surface antigen seroclearance, and 254 healthy controls were enrolled. The chronic HBV infection group included patients with hepatitis B envelope antigen (HBeAg) negative chronic hepatitis B (n = 255), with HBeAg positive chronic hepatitis B (n = 99) and with HBeAg negative HBV infection (n = 228). A total of 104 chronically infected patients were diagnosed with liver cirrhosis. Serum levels of cytokines were measured in patients with HBV infection (n = 195) and in healthy controls (n = 160). RESULTS: In adjusted multivariate analysis, the IL-10 rs1800896 AG/GG genotypes were significantly associated with an increased probability of HBV surface antigen seroclearance (OR = 1.75, 95% CI 1.04-2.94, p = 0.034), with an increased likelihood of HBeAg negative chronic infection (OR = 1.93, 95% CI 1.05-3.54, p = 0.034) and with increased serum cytokines levels in female patients. In contrast, the IL-12A rs568408 AG/AA genotypes were independently associated with an increased risk to develop liver cirrhosis, with an OR of 1.90 (95% CI 1.07-3.39, p = 0.029) in male patients. CONCLUSION: The current study shows a sex-related association of the IL-10 single-nucleotide polymorphism rs1800896 and IL-12A single-nucleotide polymorphism rs568408 with different stages of HBV infection and with HBV-related liver cirrhosis in white European patients.

13.
Health Econ ; 32(10): 2298-2321, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37408140

RESUMO

We study the link between department-wide surgeon supply and quality of care for two major elective medical procedures. Several countries have adopted policies to concentrate medical procedures in high-volume hospitals. While higher patient volumes might translate to higher quality, we provide evidence for a positive relationship between surgeon supply and hospital revision rates for hip and knee replacement surgery. Hence, hospital performance decreases with higher surgeon supply, and this finding holds conditional on patient volumes.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Cirurgiões , Humanos , Hospitais , Qualidade da Assistência à Saúde
14.
Pneumologie ; 77(1): 15-20, 2023 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-36691377

RESUMO

BACKGROUND: Available data on patients requiring prolonged mechanical ventilation due to severe COVID-19 are sparse. Here we compare patients with ARDS related or not related to SARS-CoV-2 infection treated in a specialised weaning unit. METHODS: A retrospective analysis of all patients with prolonged mechanical ventilation associated with an ARDS admitted from the 21st November 2013 to the 23rd July 2021 to the weaning unit of the University Hospital RWTH Aachen was performed. ARDS patients with COVID-19 (cARDS) were compared to patients with ARDS not related to COVID-19 (ncARDS). RESULTS: In total, n=129 patients in prolonged need for mechanical ventilation after ARDS were treated in the weaning unit, of whom n=38 had been suffering from ARDS related to COVID-19. Both patients groups were similar in terms of demographic parameters, underlying chronic illnesses, severity of ARDS and the duration of mechanical ventilation before being admitted to the weaning unit. During ICU stay, prone positioning and therapy with systemic corticosteroids was used more frequently in cARDS patients. Furthermore, therapy with vasoconstrictors was needed more often (cARDS: 42.1% vs. ncARDS 12.1%; p=0.0003) and urinary output was lower (cARDS: 1980 ml vs. ncARDS: 2600 ml; p=0.0037) in this patient group. The clinical course of the weaning process was similar in patients with cARDS and ncARDS, there were no significant differences in the occurrence of complications and the duration of mechanical ventilation. There were n=5 deaths (13.2%) in the cARDS and n=15 deaths (16.5%) in the ncARDS group. After hospital discharge, n=4 patients required non-invasive ventilation whereas out-of-hospital invasive ventilation was only necessary in one patient (all in the ncARDS group). CONCLUSION: After having survived the acute phase, the disease prognosis of patients with severe COVID-19 is favourable and most patients can be successfully weaned from mechanical ventilation. In addition, there were only minor differences compared to patients with ARDS unrelated to COVID-19.


Assuntos
COVID-19 , Síndrome do Desconforto Respiratório , Humanos , Respiração Artificial , Estudos Retrospectivos , SARS-CoV-2 , Desmame do Respirador
15.
Catheter Cardiovasc Interv ; 100(1): 145-153, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35615874

RESUMO

OBJECTIVE: To evaluate the safety and efficacy of transcatheter mitral valve repair (TMVR) in patients with chronic obstructive pulmonary disease (COPD). BACKGROUND: Heart failure and COPD share many clinical features and commonly coexist. Data about the safety and efficacy of TMVR in patients with COPD is not conclusive. METHODS: Three hundred and forty consecutive patients undergoing TMVR were retrospectively included. COPD diagnosis was based on pulmonary function tests (PFTs). Intra-hospital, 30-day- and 1-year outcomes were compared between both groups. RESULTS: Eighty-two patients had COPD (24%). There was no difference in intra-hospital mortality between patients with and without COPD (both 5%, p = 0.95). Among patients who had a successful procedure and survived to discharge there was a trend toward more rehospitalization due to decompensated heart failure at 30-day follow-up in patients with COPD (12.9% vs. 6.8%, p = 0.08) with no difference in mortality. At median follow-up of 1 year, New York heart association (NYHA) category was comparable among both groups and there was no significant difference in rehospitalization (COPD: 29.9% vs. non-COPD: 34%, p = 0.5). There was a trend toward increased 1-year mortality in COPD patients (31.2% vs. 20.6%, p = 0.06). However, a composite endpoint of rehospitalization or death at 1 year did not differ between both groups (48% vs. 42.5%, p = 0.4). Regression analysis showed no correlation between COPD severity and worse TMVR outcomes. CONCLUSIONS: COPD is highly prevalent among patients undergoing TMVR. However, TMVR seems to be safe and effective in COPD patients. COPD severity and PFT impairment alone should not be considered as a contraindication for TMVR.


Assuntos
Insuficiência Cardíaca , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Doença Pulmonar Obstrutiva Crônica , Cateterismo Cardíaco/métodos , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Estudos Retrospectivos , Resultado do Tratamento
17.
Respiration ; 101(8): 738-745, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35504262

RESUMO

BACKGROUND: In clinical practice, capillary blood taken from hyperemized earlobes (CBGE) or fingertips (CBGF) is frequently used as substitute for arterial blood (ABG) for blood gas analysis. While there is a close agreement between ABG and CBGE/CBGF regarding pH and pCO2, pO2 is often underestimated by CBG. Recently, a software tool (v-TAC®; Roche Diagnostics, Risch-Rotkreuz, Switzerland) has been developed to calculate ABG values based on a peripheral venous blood gas analysis supplemented with peripheral oxygen saturation. OBJECTIVE: Here we investigate whether v-TAC can also be used to calculate ABG values from capillary blood samples. METHODS: Patients (n = 85) with an indwelling arterial line were included in the study. A reference ABG sample (ABG1) was obtained, followed by CBGE, CBGF, and finally a second ABG (ABG2). Results of CBGE/CBGF before and after mathematical arterialization by v-TAC (aCBGE/aCBGF) were compared to ABG1. RESULTS: After mathematical arterialization by v-TAC, the mean bias in pO2 between ABG1 and CBGE went down from 5.24 mm Hg (95% limit of agreement [95% LoA]: -14.19 to 24.67) to 0.18 mm Hg (95% LoA: -11.84 to 12.20) and was in a similar range as the mean bias between ABG1 and ABG2 (0.39 mm Hg [95% LoA: -13.46 to 14.24]). Differences in pH and pCO2 between arterial and capillary samples were small before and after mathematical arterialization. Very similar results were obtained when using fingertip instead of earlobe capillary blood. CONCLUSION: In summary, v-TAC can be used for mathematical arterialization of capillary blood samples for blood gas analysis resulting in increased diagnostic accuracy for pO2.


Assuntos
Artérias , Estado Terminal , Gasometria/métodos , Dióxido de Carbono , Humanos , Oxigênio , Suíça
18.
New Phytol ; 231(3): 1040-1055, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33774818

RESUMO

Soil salinity is an increasingly global problem which hampers plant growth and crop yield. Plant productivity depends on optimal water-use efficiency and photosynthetic capacity balanced by stomatal conductance. Whether and how stomatal behavior contributes to salt sensitivity or tolerance is currently unknown. This work identifies guard cell-specific signaling networks exerted by a salt-sensitive and salt-tolerant plant under ionic and osmotic stress conditions accompanied by increasing NaCl loads. We challenged soil-grown Arabidopsis thaliana and Thellungiella salsuginea plants with short- and long-term salinity stress and monitored genome-wide gene expression and signals of guard cells that determine their function. Arabidopsis plants suffered from both salt regimes and showed reduced stomatal conductance while Thellungiella displayed no obvious stress symptoms. The salt-dependent gene expression changes of guard cells supported the ability of the halophyte to maintain high potassium to sodium ratios and to attenuate the abscisic acid (ABA) signaling pathway which the glycophyte kept activated despite fading ABA concentrations. Our study shows that salinity stress and even the different tolerances are manifested on a single cell level. Halophytic guard cells are less sensitive than glycophytic guard cells, providing opportunities to manipulate stomatal behavior and improve plant productivity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Transporte de Íons , Estômatos de Plantas/metabolismo , Estresse Salino , Plantas Tolerantes a Sal/metabolismo
19.
Phys Rev Lett ; 127(17): 177001, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34739258

RESUMO

The recent discovery of AV_{3}Sb_{5} (A=K,Rb,Cs) has uncovered an intriguing arena for exotic Fermi surface instabilities in a kagome metal. Among them, superconductivity is found in the vicinity of multiple van Hove singularities, exhibiting indications of unconventional pairing. We show that the sublattice interference mechanism is central to understanding the formation of superconductivity in a kagome metal. Starting from an appropriately chosen minimal tight-binding model with multiple van Hove singularities close to the Fermi level for AV_{3}Sb_{5}, we provide a random phase approximation analysis of superconducting instabilities. Nonlocal Coulomb repulsion, the sublattice profile of the van Hove bands, and the interaction strength turn out to be the crucial parameters to determine the preferred pairing symmetry. Implications for potentially topological surface states are discussed, along with a proposal for additional measurements to pin down the nature of superconductivity in AV_{3}Sb_{5}.

20.
BMC Med Imaging ; 21(1): 28, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588783

RESUMO

BACKGROUND: Recent studies provide evidence that hepatocellular  adenomas  (HCAs) frequently take up gadoxetic acid (Gd-EOB) during the hepatobiliary phase (HBP). The purpose of our study was to investigate how to differentiate between Gd-EOB-enhancing HCAs and focal nodular hyperplasias (FNHs). We therefore retrospectively included 40 HCAs classified as HBP Gd-EOB-enhancing lesions from a sample of 100 histopathologically proven HCAs in 65 patients. These enhancing HCAs were matched retrospectively with 28 FNH lesions (standard of reference: surgical resection). Two readers (experienced abdominal radiologists blinded to clinical data) reviewed the images evaluating morphologic features and subjectively scoring Gd-EOB uptake (25-50%, 50-75% and 75-100%) for each lesion. Quantitative lesion-to-liver enhancement was measured in arterial, portal venous (PV), transitional and HBP. Additionally, multivariate regression analyses were performed. RESULTS: Subjective scoring of intralesional Gd-EOB uptake showed the highest discriminatory accuracies (AUC: 0.848 (R#1); 0.920 (R#2)-p < 0.001) with significantly higher uptake scores assigned to FNHs (Cut-off: 75%-100%). Typical lobulation and presence of a central scar in FNH achieved an accuracy of 0.750 or higher in at least one reader (lobulation-AUC: 0.809 (R#1); 0.736 (R#2); central scar-AUC: 0.595 (R#1); 0.784 (R#2)). The multivariate regression emphasized the discriminatory power of the Gd-EOB scoring (p = 0.001/OR:22.15 (R#1) and p < 0.001/OR:99.12 (R#2). The lesion-to-liver ratio differed significantly between FNH and HCA in the PV phase and HBP (PV: 132.9 (FNH) and 110.2 (HCA), p = 0.048 and HBP: 110.3 (FNH) and 39.2 (HCA), p < 0.001)), while the difference was not significant in arterial and transitional contrast phases (p > 0.05). CONCLUSION: Even in HBP-enhancing HCA, characterization of Gd-EOB uptake was found to provide the strongest discriminatory power in differentiating HCA from FNH. Furthermore, a lobulated appearance and a central scar are more frequently seen in FNH than in HCA.


Assuntos
Adenoma de Células Hepáticas/diagnóstico por imagem , Meios de Contraste/farmacologia , Hiperplasia Nodular Focal do Fígado/diagnóstico por imagem , Gadolínio DTPA/farmacocinética , Neoplasias Hepáticas/diagnóstico por imagem , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adenoma de Células Hepáticas/metabolismo , Adulto , Carcinoma Hepatocelular , Diagnóstico Diferencial , Feminino , Hiperplasia Nodular Focal do Fígado/metabolismo , Humanos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/metabolismo , Masculino , Curva ROC , Análise de Regressão , Sensibilidade e Especificidade
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