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1.
Front Plant Sci ; 15: 1333249, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628362

RESUMO

Biostimulants (Bio-effectors, BEs) comprise plant growth-promoting microorganisms and active natural substances that promote plant nutrient-acquisition, stress resilience, growth, crop quality and yield. Unfortunately, the effectiveness of BEs, particularly under field conditions, appears highly variable and poorly quantified. Using random model meta-analyses tools, we summarize the effects of 107 BE treatments on the performance of major crops, mainly conducted within the EU-funded project BIOFECTOR with a focus on phosphorus (P) nutrition, over five years. Our analyses comprised 94 controlled pot and 47 field experiments under different geoclimatic conditions, with variable stress levels across European countries and Israel. The results show an average growth/yield increase by 9.3% (n=945), with substantial differences between crops (tomato > maize > wheat) and growth conditions (controlled nursery + field (Seed germination and nursery under controlled conditions and young plants transplanted to the field) > controlled > field). Average crop growth responses were independent of BE type, P fertilizer type, soil pH and plant-available soil P (water-P, Olsen-P or Calcium acetate lactate-P). BE effectiveness profited from manure and other organic fertilizers, increasing soil pH and presence of abiotic stresses (cold, drought/heat or salinity). Systematic meta-studies based on published literature commonly face the inherent problem of publication bias where the most suspected form is the selective publication of statistically significant results. In this meta-analysis, however, the results obtained from all experiments within the project are included. Therefore, it is free of publication bias. In contrast to reviews of published literature, our unique study design is based on a common standardized protocol which applies to all experiments conducted within the project to reduce sources of variability. Based on data of crop growth, yield and P acquisition, we conclude that application of BEs can save fertilizer resources in the future, but the efficiency of BE application depends on cropping systems and environments.

2.
Atherosclerosis ; 392: 117504, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38513436

RESUMO

BACKGROUND AND AIMS: The effects of protein convertase subtilisin/kexin type 9 (PCSK9) inhibitors on endothelial function as assessed by flow-mediated dilation (FMD) in patients with acute myocardial infarction (AMI) are unknown. Therefore, we aimed to investigate the effects of the PCSK9 inhibitor alirocumab added to high-intensity statin on FMD, and its association with coronary atherosclerosis in non-infarct related arteries using intracoronary intravascular ultrasound (IVUS), near-infrared spectroscopy (NIRS), and optical coherence tomography (OCT). METHODS: This was a pre-specified substudy among patients recruited at Bern University Hospital, Switzerland, for the randomized-controlled, double-blind, PACMAN-AMI trial, which compared the effects of biweekly alirocumab 150 mg vs. placebo added to rosuvastatin. Brachial artery FMD was measured at 4 and 52 weeks, and intracoronary imaging at baseline and 52 weeks. RESULTS: 139/173 patients completed the substudy. There was no difference in FMD at 52 weeks in the alirocumab (n = 68, 5.44 ± 2.24%) versus placebo (n = 71, 5.45 ± 2.19%) group (difference = -0.21%, 95% CI -0.77 to 0.35, p = 0.47). FMD improved throughout 52 weeks in both groups similarly (p < 0.001). There was a significant association between 4 weeks FMD and baseline plaque burden (IVUS) (n = 139, slope = -1.00, p = 0.006), but not with lipid pool (NIRS) (n = 139, slope = -7.36, p = 0.32), or fibrous cap thickness (OCT) (n = 81, slope = -1.57, p = 0.62). CONCLUSIONS: Among patients with AMI, the addition of alirocumab did not result in further improvement of FMD as compared to 52 weeks secondary preventative medical therapy including high-intensity statin therapy. FMD was significantly associated with coronary plaque burden at baseline, but not with lipid pool or fibrous cap thickness.


Assuntos
Anticorpos Monoclonais Humanizados , Doença da Artéria Coronariana , Endotélio Vascular , Inibidores de Hidroximetilglutaril-CoA Redutases , Infarto do Miocárdio , Inibidores de PCSK9 , Rosuvastatina Cálcica , Ultrassonografia de Intervenção , Humanos , Masculino , Feminino , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/farmacologia , Pessoa de Meia-Idade , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/complicações , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Método Duplo-Cego , Idoso , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/fisiopatologia , Rosuvastatina Cálcica/uso terapêutico , Resultado do Tratamento , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Tomografia de Coerência Óptica , Vasodilatação/efeitos dos fármacos , Quimioterapia Combinada , Espectroscopia de Luz Próxima ao Infravermelho , Placa Aterosclerótica/tratamento farmacológico , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiopatologia , Artéria Braquial/efeitos dos fármacos , Artéria Braquial/fisiopatologia , Artéria Braquial/diagnóstico por imagem , Fatores de Tempo , Pró-Proteína Convertase 9
3.
Nat Struct Mol Biol ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321148

RESUMO

Despite the importance of citrullination in physiology and disease, global identification of citrullinated proteins, and the precise targeted sites, has remained challenging. Here we employed quantitative-mass-spectrometry-based proteomics to generate a comprehensive atlas of citrullination sites within the HL60 leukemia cell line following differentiation into neutrophil-like cells. We identified 14,056 citrullination sites within 4,008 proteins and quantified their regulation upon inhibition of the citrullinating enzyme PADI4. With this resource, we provide quantitative and site-specific information on thousands of PADI4 substrates, including signature histone marks and transcriptional regulators. Additionally, using peptide microarrays, we demonstrate the potential clinical relevance of certain identified sites, through distinct reactivities of antibodies contained in synovial fluid from anti-CCP-positive and anti-CCP-negative people with rheumatoid arthritis. Collectively, we describe the human citrullinome at a systems-wide level, provide a resource for understanding citrullination at the mechanistic level and link the identified targeted sites to rheumatoid arthritis.

4.
JACC Cardiovasc Interv ; 17(1): 17-28, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38199749

RESUMO

BACKGROUND: Evidence to support immediate P2Y12 inhibitor loading in ST-segment elevation myocardial infarction (STEMI) is limited. OBJECTIVES: This study sought to compare outcomes of STEMI patients receiving immediate or delayed P2Y12 inhibitor treatment. METHODS: Using data from the prospective Bern-PCI registry between 2016 and 2020, we stratified STEMI patients undergoing percutaneous coronary intervention according to time periods with different institutional recommendations regarding P2Y12 inhibitor pretreatment. In cohort 1 (October 2016-September 2018), immediate P2Y12 inhibitor treatment was recommended. In cohort 2 (October 2018-September 2020), P2Y12 inhibitor treatment was recommended after coronary anatomy was confirmed. The primary endpoint was a composite of major adverse cardiac or cerebrovascular events (MACCEs) defined as all-cause death, recurrent myocardial infarction, stroke, or definite stent thrombosis at 30 days. Sensitivity analysis included only patients in whom these recommendations were followed. RESULTS: Cohort 1 included 1,116 patients; pretreatment was actually given in 708 (63.4%). Cohort 2 included 847 patients; pretreatment was withheld in 798 (94.2%). The mean age was 65 ± 13 years, and 24% were female. Baseline characteristics were well-balanced between groups. The median difference for P2Y12 loading to angiography was 52 minutes between cohort 1 and 2 and 100 minutes between patients receiving vs not receiving pretreatment. Rates of MACCEs were similar between cohort 1 and cohort 2 (10.1% vs 8.1%; adjusted HR: 0.91; 95% CI: 0.65-1.28; P = 0.59) and between patients receiving vs not receiving pretreatment (7.1% vs 8.4%; adjusted HR: 1.17; 95% CI: 0.78-1.74; P = 0.45). CONCLUSIONS: In this cohort study of patients with STEMI undergoing primary percutaneous coronary intervention, P2Y12 inhibitor pretreatment was not associated with improved MACCEs.


Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Estudos de Coortes , Intervenção Coronária Percutânea/efeitos adversos , Estudos Prospectivos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Resultado do Tratamento , Sistema de Registros
5.
Nat Nanotechnol ; 19(2): 196-201, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38049597

RESUMO

Interlayer excitons in van der Waals heterostructures are fascinating for applications like exciton condensation, excitonic devices and moiré-induced quantum emitters. The study of these charge-transfer states has almost exclusively focused on band edges, limiting the spectral region to the near-infrared regime. Here we explore the above-gap analogues of interlayer excitons in bilayer WSe2 and identify both neutral and charged species emitting in the ultraviolet. Even though the transitions occur far above the band edge, the states remain metastable, exhibiting linewidths as narrow as 1.8 meV. These interlayer high-lying excitations have switchable dipole orientations and hence show prominent Stark splitting. The positive and negative interlayer high-lying trions exhibit significant binding energies of 20-30 meV, allowing for a broad tunability of transitions via electric fields and electrostatic doping. The Stark splitting of these trions serves as a highly accurate, built-in sensor for measuring interlayer electric field strengths, which are exceedingly difficult to quantify otherwise. Such excitonic complexes are further sensitive to the interlayer twist angle and offer opportunities to explore emergent moiré physics under electrical control. Our findings more than double the accessible energy range for applications based on interlayer excitons.

6.
Eur Heart J ; 45(3): 161-177, 2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-37638967

RESUMO

BACKGROUND AND AIMS: The European Union Medical Device Regulation 2017/745 challenges key stakeholders to follow transparent and rigorous approaches to the clinical evaluation of medical devices. The purpose of this study is a systematic evaluation of published clinical evidence underlying selected high-risk cardiovascular medical devices before and after market access in the European Union (CE-marking) between 2000 and 2021. METHODS: Pre-specified strategies were applied to identify published studies of prospective design evaluating 71 high-risk cardiovascular devices in seven different classes (bioresorbable coronary scaffolds, left atrial appendage occlusion devices, transcatheter aortic valve implantation systems, transcatheter mitral valve repair/replacement systems, surgical aortic and mitral heart valves, leadless pacemakers, subcutaneous implantable cardioverter-defibrillator). The search time span covered 20 years (2000-21). Details of study design, patient population, intervention(s), and primary outcome(s) were summarized and assessed with respect to timing of the corresponding CE-mark approval. RESULTS: At least one prospective clinical trial was identified for 70% (50/71) of the pre-specified devices. Overall, 473 reports of 308 prospectively designed studies (enrolling 97 886 individuals) were deemed eligible, including 81% (251/308) prospective non-randomized clinical trials (66 186 individuals) and 19% (57/308) randomized clinical trials (31 700 individuals). Pre-registration of the study protocol was available in 49% (150/308) studies, and 16% (48/308) had a peer-reviewed publicly available protocol. Device-related adverse events were evaluated in 82% (253/308) of studies. An outcome adjudication process was reported in 39% (120/308) of the studies. Sample size was larger for randomized in comparison to non-randomized trials (median of 304 vs. 100 individuals, P < .001). No randomized clinical trial published before CE-mark approval for any of the devices was identified. Non-randomized clinical trials were predominantly published after the corresponding CE-mark approval of the device under evaluation (89%, 224/251). Sample sizes were smaller for studies published before (median of 31 individuals) than after (median of 135 individuals) CE-mark approval (P < .001). Clinical trials with larger sample sizes (>50 individuals) and those with longer recruitment periods were more likely to be published after CE-mark approval, and were more frequent during the period 2016-21. CONCLUSIONS: The quantity and quality of publicly available data from prospective clinical investigations across selected categories of cardiovascular devices, before and after CE approval during the period 2000-21, were deemed insufficient. The majority of studies was non-randomized, with increased risk of bias, and performed in small populations without provision of power calculations, and none of the reviewed devices had randomized trial results published prior to CE-mark certification.


Assuntos
Sistema Cardiovascular , Substituição da Valva Aórtica Transcateter , Humanos , Coração , Próteses e Implantes , União Europeia
7.
Ultrasound Med Biol ; 50(2): 277-284, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38040522

RESUMO

OBJECTIVE: Focused assessment with sonography for trauma (FAST) is a valuable ultrasound procedure in emergency settings, and there is a need for evidence-based education in FAST to ensure competencies. Immersive virtual reality (IVR) is a progressive training modality gaining traction in the field of ultrasound training. IVR holds several economic and practical advantages to the common instructor-led FAST courses using screen-based simulation (SBS). METHODS: This prospective, interventional cohort study investigated whether training FAST using IVR unsupervised and out-of-hospital was non-inferior to a historical control group training at a 90 min SBS course in terms of developing FAST competencies in novices. Competencies were assessed in both groups using the same post-training simulation-based FAST test with validity evidence, and a non-inferiority margin of 2 points was chosen. RESULTS: A total of 27 medical students attended the IVR course, and 27 junior doctors attended the SBS course. The IVR group trained for a median time of 117 min and scored a mean 14.2 ± 2.0 points, compared with a mean 13.7 ± 2.5 points in the SBS group. As the lower bound of the 95% confidence interval at 13.6 was within the range of the non-inferiority margin (11.7-13.7 points), training FAST in IVR for a median of 117 min was found non-inferior to training at a 90 min SBS course. No significant correlation was found between time spent in IVR and test scores. CONCLUSION: Within the limitations of the use of a historical control group, the results suggest that IVR could be an alternative to SBS FAST training and suitable for unsupervised, out-of-hospital courses in basic FAST competencies.


Assuntos
Avaliação Sonográfica Focada no Trauma , Realidade Virtual , Humanos , Estudos de Coortes , Estudos Prospectivos , Ultrassonografia , Competência Clínica
8.
Nat Commun ; 14(1): 8134, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38065956

RESUMO

Modified vaccinia Ankara (MVA) virus does not replicate in human cells and is the vaccine deployed to curb the current outbreak of mpox. Here, we conduct a multiplexed proteomic analysis to quantify >9000 cellular and ~80% of viral proteins throughout MVA infection of human fibroblasts and macrophages. >690 human proteins are down-regulated >2-fold by MVA, revealing a substantial remodelling of the host proteome. >25% of these MVA targets are not shared with replication-competent vaccinia. Viral intermediate/late gene expression is necessary for MVA antagonism of innate immunity, and suppression of interferon effectors such as ISG20 potentiates virus gene expression. Proteomic changes specific to infection of macrophages indicate modulation of the inflammatory response, including inflammasome activation. Our approach thus provides a global view of the impact of MVA on the human proteome and identifies mechanisms that may underpin its abortive infection. These discoveries will prove vital to design future generations of vaccines.


Assuntos
Vacínia , Humanos , Proteoma , Proteômica , Vaccinia virus/genética , Morte Celular , Antivirais
9.
Front Cardiovasc Med ; 10: 1294930, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38116535

RESUMO

Aims of the study: Percutaneous coronary intervention (PCI) exposes operators to ionizing radiation. Robotic-assisted PCI (RA-PCI) is a novel technology that enables interventional cardiologists to operate coronary devices remotely from a radiation-shed cockpit. The aim of this study is to describe the experience and challenges during the initiation of a RA-PCI program and to report outcomes of the first 21 patients undergoing RA-PCI in Switzerland. Methods: All patients undergoing RA-PCI using the CorPath GRX Vascular Robotic System between 06/2021 and 12/2021 at Inselspital, Bern University Hospital were included in this retrospective registry study. Baseline, procedural and clinical follow-up data were prospectively assessed as part of the Cardiobase Bern PCI registry (NCT02241291). The two endpoints of interest were clinical success [defined as <30% residual diameter stenosis in the absence of in-hospital major adverse cardiovascular events (MACE: composite of death, periprocedural myocardial infarction, target-vessel revascularization, and stroke)] and robotic success (defined as clinical success and completion of RA-PCI without or with partial manual assistance). Additional outcome measures include clinical long-term outcomes at one year. Results: Twenty-five lesions in 21 patients were treated with RA-PCI (age 62.4 ± 9.1 years, 24% female). Clinical success was achieved in 100%, and robotic success in 81% (17/21 procedures, including 4 procedures requiring partial manual assistance). Manual conversion (e.g. manual completion of the procedure) occurred in 19% (4 procedures). Reasons for manual assistance or conversion were poor guiding-catheter back-up or platform limitations (4), adverse events (2x transient slow-flow that was solved manually), safety decision (1x vasovagal reaction not related to robotic approach), and software error (1). No in-hospital MACE occurred. During 12 months of follow-up, one patient suffered a non-target-vessel myocardial infarction requiring repeat PCI. Conclusions: RA-PCI can safely be performed without clinically relevant robot-associated complications in selected patients with approximately 80% of procedures conducted without or with partial manual assistance.

10.
PNAS Nexus ; 2(12): pgad406, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38111822

RESUMO

Extensive efforts are underway to develop bacteriophages as therapies against antibiotic-resistant bacteria. However, these efforts are confounded by the instability of phage preparations and a lack of suitable tools to assess active phage concentrations over time. In this study, we use dynamic light scattering (DLS) to measure changes in phage physical state in response to environmental factors and time, finding that phages tend to decay and form aggregates and that the degree of aggregation can be used to predict phage bioactivity. We then use DLS to optimize phage storage conditions for phages from human clinical trials, predict bioactivity in 50-y-old archival stocks, and evaluate phage samples for use in a phage therapy/wound infection model. We also provide a web application (Phage-Estimator of Lytic Function) to facilitate DLS studies of phages. We conclude that DLS provides a rapid, convenient, and nondestructive tool for quality control of phage preparations in academic and commercial settings.

11.
Sci Transl Med ; 15(722): eadh9562, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37967201

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is generally refractory to immune checkpoint blockade, although patients with genetically unstable tumors can show modest therapeutic benefit. We previously demonstrated the presence of tumor-reactive CD8+ T cells in PDAC samples. Here, we charted the tumor-infiltrating T cell repertoire in PDAC by combining single-cell transcriptomics with functional testing of T cell receptors (TCRs) for reactivity against autologous tumor cells. On the basis of a comprehensive dataset including 93 tumor-reactive and 65 bystander TCR clonotypes, we delineated a gene signature that effectively distinguishes between these T cell subsets in PDAC, as well as in other tumor indications. This revealed a high frequency of tumor-reactive TCR clonotypes in three genetically unstable samples. In contrast, the T cell repertoire in six genetically stable PDAC tumors was largely dominated by bystander T cells. Nevertheless, multiple tumor-reactive TCRs were successfully identified in each of these samples, thereby providing a perspective for personalized immunotherapy in this treatment-resistant indication.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Linfócitos T CD8-Positivos , Transcriptoma/genética , Receptores de Antígenos de Linfócitos T/genética , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas
12.
Microbiol Resour Announc ; 12(11): e0079323, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37905824

RESUMO

We purified two novel bacteriophages from soil collected in Sioux County, Iowa: BAjuniper and Tedro. These bacteriophages were isolated from the host, Microbacterium foliorum. BAjuniper was assigned to cluster EB, and Tedro was assigned to cluster EF. Both phages display genomes typical of other phages in their clusters.

13.
Healthcare (Basel) ; 11(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37761717

RESUMO

Despite proven effectiveness, compression therapy is applied in only 20-40% of patients with venous leg ulceration, leading to avoidable chronification and morbidity. The Ulcus Cruris Care project was established to develop a new disease-management concept comparable to existing programs for chronic diseases to support evidence-based treatment of venous leg ulceration. This prospective controlled study assessed its first implementation. Interventional elements comprised online training for general practitioner practices, software support for case management, and educational materials for patients. A total of 20 practices and 40 patients were enrolled in a 1:1 ratio to the intervention and control group. Guideline-conform compression therapy was applied more frequently in the intervention group (19/20 [95%] vs. 11/19 [58%]; p = 0.006). For patients with ulcers existing ≤ 6 months, the healing rate at 12 weeks was 8/11 [73%] (intervention) compared to 4/11 [36%] (control; p = 0.087). Patients after intervention had higher scores for self-help and education in the PACIC-5A questionnaire (42.9 ± 41.6 vs. 11.4 ± 28.8; p = 0.044). Treatment costs were EUR 1.380 ± 1.347 (intervention) and EUR 2.049 ± 2.748 (control; p = 0.342). The results of this study indicate that the Ulcus Cruris Care intervention may lead to a significant improvement in care. Consequently, a broader rollout in German healthcare seems warranted.

14.
Thromb Haemost ; 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37595625

RESUMO

OBJECTIVE: The effect of the PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitor alirocumab on platelet aggregation among patients with acute myocardial infarction (AMI) remains unknown. We aimed to explore the effect of alirocumab added to high-intensity statin therapy on P2Y12 reaction unit (PRU) among AMI patients receiving dual antiplatelet therapy (DAPT) with a potent P2Y12 inhibitor (ticagrelor or prasugrel). In addition, we assessed circulating platelet-derived noncoding RNAs (microRNAs and YRNAs). METHODS: This was a prespecified, powered, pharmacodynamic substudy of the PACMAN trial, a randomized, double-blind trial comparing biweekly alirocumab (150 mg) versus placebo in AMI patients undergoing percutaneous coronary intervention. Patients recruited at Bern University Hospital, receiving DAPT with a potent P2Y12 inhibitor, and adherent to the study drug (alirocumab or placebo) were analyzed for the current study. The primary endpoint was PRU at 4 weeks after study drug initiation as assessed by VerifyNow P2Y12 point-of-care assays. RESULTS: Among 139 randomized patients, the majority of patients received ticagrelor DAPT at 4 weeks (57 [86.4%] in the alirocumab group vs. 69 [94.5%] in the placebo group, p = 0.14). There were no significant differences in the primary endpoint PRU at 4 weeks between groups (12.5 [interquartile range, IQR: 27.0] vs. 19.0 [IQR: 30.0], p = 0.26). Consistent results were observed in 126 patients treated with ticagrelor (13.0 [IQR: 20.0] vs. 18.0 [IQR: 27.0], p = 0.28). Similarly, platelet-derived noncoding RNAs did not significantly differ between groups. CONCLUSION: Among AMI patients receiving DAPT with a potent P2Y12 inhibitor, alirocumab had no significant effect on platelet reactivity as assessed by PRU and platelet-derived noncoding RNAs.

15.
Nature ; 620(7975): 873-880, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37558876

RESUMO

Human tripartite motif protein 5α (TRIM5α) is a well-characterized restriction factor for some RNA viruses, including HIV1-5; however, reports are limited for DNA viruses6,7. Here we demonstrate that TRIM5α also restricts orthopoxviruses and, via its SPRY domain, binds to the orthopoxvirus capsid protein L3 to diminish virus replication and activate innate immunity. In response, several orthopoxviruses, including vaccinia, rabbitpox, cowpox, monkeypox, camelpox and variola viruses, deploy countermeasures. First, the protein C6 binds to TRIM5 via the RING domain to induce its proteasome-dependent degradation. Second, cyclophilin A (CypA) is recruited via interaction with the capsid protein L3 to virus factories and virions to antagonize TRIM5α; this interaction is prevented by cyclosporine A (CsA) and the non-immunosuppressive derivatives alisporivir and NIM811. Both the proviral effect of CypA and the antiviral effect of CsA are dependent on TRIM5α. CsA, alisporivir and NIM811 have antiviral activity against orthopoxviruses, and because these drugs target a cellular protein, CypA, the emergence of viral drug resistance is difficult. These results warrant testing of CsA derivatives against orthopoxviruses, including monkeypox and variola.


Assuntos
Fatores de Restrição Antivirais , Ciclofilina A , Poxviridae , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases , Proteínas Virais , Humanos , Antivirais/metabolismo , Fatores de Restrição Antivirais/metabolismo , Proteínas do Capsídeo/metabolismo , Linhagem Celular , Ciclofilina A/metabolismo , Poxviridae/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Virais/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo
16.
Nat Commun ; 14(1): 5057, 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37598179

RESUMO

Atomically thin layered van der Waals heterostructures feature exotic and emergent optoelectronic properties. With growing interest in these novel quantum materials, the microscopic understanding of fundamental interfacial coupling mechanisms is of capital importance. Here, using multidimensional photoemission spectroscopy, we provide a layer- and momentum-resolved view on ultrafast interlayer electron and energy transfer in a monolayer-WSe2/graphene heterostructure. Depending on the nature of the optically prepared state, we find the different dominating transfer mechanisms: while electron injection from graphene to WSe2 is observed after photoexcitation of quasi-free hot carriers in the graphene layer, we establish an interfacial Meitner-Auger energy transfer process following the excitation of excitons in WSe2. By analysing the time-energy-momentum distributions of excited-state carriers with a rate-equation model, we distinguish these two types of interfacial dynamics and identify the ultrafast conversion of excitons in WSe2 to valence band transitions in graphene. Microscopic calculations find interfacial dipole-monopole coupling underlying the Meitner-Auger energy transfer to dominate over conventional Förster- and Dexter-type interactions, in agreement with the experimental observations. The energy transfer mechanism revealed here might enable new hot-carrier-based device concepts with van der Waals heterostructures.

17.
bioRxiv ; 2023 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-37425882

RESUMO

Extensive efforts are underway to develop bacteriophages as therapies against antibiotic-resistant bacteria. However, these efforts are confounded by the instability of phage preparations and a lack of suitable tools to assess active phage concentrations over time. Here, we use Dynamic Light Scattering (DLS) to measure changes in phage physical state in response to environmental factors and time, finding that phages tend to decay and form aggregates and that the degree of aggregation can be used to predict phage bioactivity. We then use DLS to optimize phage storage conditions for phages from human clinical trials, predict bioactivity in 50-year-old archival stocks, and evaluate phage samples for use in a phage therapy/wound infection model. We also provide a web-application (Phage-ELF) to facilitate DLS studies of phages. We conclude that DLS provides a rapid, convenient, and non-destructive tool for quality control of phage preparations in academic and commercial settings.

18.
Protein Sci ; 32(9): e4733, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37463013

RESUMO

Intrinsically disordered proteins (IDPs) are often multifunctional and frequently posttranslationally modified. Deleted in split hand/split foot 1 (Dss1-Sem1 in budding yeast) is a highly multifunctional IDP associated with a range of protein complexes. However, it remains unknown if the different functions relate to different modified states. In this work, we show that Schizosaccharomyces pombe Dss1 is a substrate for casein kinase 2 in vitro, and we identify three phosphorylated threonines in its linker region separating two known disordered ubiquitin-binding motifs. Phosphorylations of the threonines had no effect on ubiquitin-binding but caused a slight destabilization of the C-terminal α-helix and mediated a direct interaction with the forkhead-associated (FHA) domain of the RING-FHA E3-ubiquitin ligase defective in mitosis 1 (Dma1). The phosphorylation sites are not conserved and are absent in human Dss1. Sequence analyses revealed that the Txx(E/D) motif, which is important for phosphorylation and Dma1 binding, is not linked to certain branches of the evolutionary tree. Instead, we find that the motif appears randomly, supporting the mechanism of ex nihilo evolution of novel motifs. In support of this, other threonine-based motifs, although frequent, are nonconserved in the linker, pointing to additional functions connected to this region. We suggest that Dss1 acts as an adaptor protein that docks to Dma1 via the phosphorylated FHA-binding motifs, while the C-terminal α-helix is free to bind mitotic septins, thereby stabilizing the complex. The presence of Txx(D/E) motifs in the disordered regions of certain septin subunits may be of further relevance to the formation and stabilization of these complexes.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Ubiquitina-Proteína Ligases , Humanos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Fosforilação , Ligação Proteica , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
19.
EuroIntervention ; 19(4): e286-e296, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37341586

RESUMO

BACKGROUND: Treatment with proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors on top of statins leads to plaque regression and stabilisation. The effects of PCSK9 inhibitors on coronary physiology and angiographic diameter stenosis (DS%) are unknown. AIMS: This study aimed to investigate the effects of the PCSK9 inhibitor alirocumab on coronary haemodynamics as assessed by quantitative flow ratio (QFR) and DS% by three-dimensional quantitative coronary angiography (3D-QCA) in non-infarct-related arteries (non-IRA) among acute myocardial infarction (AMI) patients. METHODS: This was a prespecified substudy of the randomised controlled PACMAN-AMI trial, comparing alirocumab versus placebo on top of rosuvastatin. QFR and 3D-QCA were assessed at baseline and 1 year in any non-IRA ≥2.0 mm and 3D-QCA DS% >25%. The prespecified primary endpoint was the number of patients with a mean QFR increase at 1 year, and the secondary endpoint was the change in 3D-QCA DS%. RESULTS: Of 300 enrolled patients, 265 had serial follow-up, of which 193 underwent serial QFR/3D-QCA analysis in 282 non-IRA. At 1 year, QFR increased in 50/94 (53.2%) patients with alirocumab versus 40/99 (40.4%) with placebo (Δ12.8%; odds ratio 1.7, 95% confidence interval [CI]: 0.9 to 3.0; p=0.076). DS% decreased by 1.03±7.28% with alirocumab and increased by 1.70±8.27% with placebo (Δ-2.50%, 95% CI: -4.43 to -0.57; p=0.011). CONCLUSIONS: Treatment of AMI patients with alirocumab versus placebo for 1 year resulted in a significant regression in angiographic DS%, whereas no overall improvement of coronary haemodynamics was observed. CLINICALTRIALS: gov: NCT03067844.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Infarto do Miocárdio , Placa Aterosclerótica , Humanos , Pró-Proteína Convertase 9 , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Placa Aterosclerótica/tratamento farmacológico , Artérias
20.
J Med Chem ; 66(9): 6297-6314, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37130057

RESUMO

Fragment-based drug discovery has played an important role in medicinal chemistry and pharmaceutical research. Despite numerous demonstrated successes, the limited diversity and overrepresentation of planar, sp2-rich structures in commercial libraries often hamper the full potential of this approach. Hence, the thorough design of screening libraries inevitably determines the probability for meaningful hits and subsequent structural elaboration. Against this background, we present the generation of an exclusive fragment library based on iterative entry nomination by a specifically designed computational workflow: "Fragtory". Following a pharmacophore diversity-driven approach, we used Fragtory in an interdisciplinary academic setting to guide both tailored synthesis efforts and the implementation of in-house compounds to build a curated 288-member library of sp3-enriched fragments. Subsequent NMR screens against a model protein and hit validation by protein crystallography led to the identification of structurally novel ligands that were further characterized by isothermal titration calorimetry, demonstrating the applicability of our experimental approach.


Assuntos
Descoberta de Drogas , Farmacóforo , Proteínas , Ligação Proteica , Ligantes , Desenho de Fármacos
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