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1.
Acta Neuropathol ; 148(1): 2, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980441

RESUMO

Proteolytic cell surface release ('shedding') of the prion protein (PrP), a broadly expressed GPI-anchored glycoprotein, by the metalloprotease ADAM10 impacts on neurodegenerative and other diseases in animal and in vitro models. Recent studies employing the latter also suggest shed PrP (sPrP) to be a ligand in intercellular communication and critically involved in PrP-associated physiological tasks. Although expectedly an evolutionary conserved event, and while soluble forms of PrP are present in human tissues and body fluids, for the human body neither proteolytic PrP shedding and its cleavage site nor involvement of ADAM10 or the biological relevance of this process have been demonstrated thus far. In this study, cleavage site prediction and generation (plus detailed characterization) of sPrP-specific antibodies enabled us to identify PrP cleaved at tyrosin 226 as the physiological and apparently strictly ADAM10-dependent shed form in humans. Using cell lines, neural stem cells and brain organoids, we show that shedding of human PrP can be stimulated by PrP-binding ligands without targeting the protease, which may open novel therapeutic perspectives. Site-specific antibodies directed against human sPrP also detect the shed form in brains of cattle, sheep and deer, hence in all most relevant species naturally affected by fatal and transmissible prion diseases. In human and animal prion diseases, but also in patients with Alzheimer`s disease, sPrP relocalizes from a physiological diffuse tissue pattern to intimately associate with extracellular aggregated deposits of misfolded proteins characteristic for the respective pathological condition. Findings and research tools presented here will accelerate novel insight into the roles of PrP shedding (as a process) and sPrP (as a released factor) in neurodegeneration and beyond.


Assuntos
Proteína ADAM10 , Secretases da Proteína Precursora do Amiloide , Doenças Neurodegenerativas , Humanos , Proteína ADAM10/metabolismo , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Proteínas Priônicas/metabolismo , Proteínas de Membrana/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Anticorpos
2.
J Clin Invest ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888964

RESUMO

The ß-secretase BACE1 is a central drug target for Alzheimer's disease. Clinically tested, BACE1-directed inhibitors also block the homologous protease BACE2. Yet, little is known about physiological BACE2 substrates and functions in vivo. Here, we identify BACE2 as the protease shedding the lymphangiogenic vascular endothelial growth factor receptor 3 (VEGFR3). Inactivation of BACE2, but not BACE1, inhibited shedding of VEGFR3 from primary human lymphatic endothelial cells (LECs) and reduced release of the shed, soluble VEGFR3 (sVEGFR3) ectodomain into the blood of mice, non-human primates and humans. Functionally, BACE2 inactivation increased full-length VEGFR3 and enhanced VEGFR3 signaling in LECs and also in vivo in zebrafish, where enhanced migration of LECs was observed. Thus, this study identifies BACE2 as a modulator of lymphangiogenic VEGFR3 signaling and demonstrates the utility of sVEGFR3 as a pharmacodynamic plasma marker for BACE2 activity in vivo, a prerequisite for developing BACE1-selective inhibitors for a safer prevention of Alzheimer's disease.

3.
Infection ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896372

RESUMO

PURPOSE: There is evidence that lower activity of the RAF/MEK/ERK network is associated with positive outcomes in mild and moderate courses of COVID-19. The effect of this cascade in COVID-19 sepsis is still undetermined. Therefore, we tested the hypothesis that activity of the RAF/MEK/ERK network in COVID-19-induced sepsis is associated with an impact on 30-day survival. METHODS: We used biomaterial from 81 prospectively recruited patients from the multicentric CovidDataNet.NRW-study cohort (German clinical trial registry: DRKS00026184) with their collected medical history, vital signs, laboratory parameters, microbiological findings and patient outcome. ERK activity was measured by evaluating ERK phosphorylation using a Proximity Ligation Assay. RESULTS: An increased ERK activity at 4 days after diagnosis of COVID-19-induced sepsis was associated with a more than threefold increased chance of survival in an adjusted Cox regression model. ERK activity was independent of other confounders such as Charlson Comorbidity Index or SOFA score (HR 0.28, 95% CI 0.10-0.84, p = 0.02). CONCLUSION: High activity of the RAF/MEK/ERK network during the course of COVID-19 sepsis is a protective factor and may indicate recovery of the immune system. Further studies are needed to confirm these results.

4.
Sci Adv ; 10(23): eadj0385, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38848354

RESUMO

Excess gene dosage from chromosome 21 (chr21) causes Down syndrome (DS), spanning developmental and acute phenotypes in terminal cell types. Which phenotypes remain amenable to intervention after development is unknown. To address this question in a model of DS neurogenesis, we derived trisomy 21 (T21) human induced pluripotent stem cells (iPSCs) alongside, otherwise, isogenic euploid controls from mosaic DS fibroblasts and equipped one chr21 copy with an inducible XIST transgene. Monoallelic chr21 silencing by XIST is near-complete and irreversible in iPSCs. Differential expression reveals that T21 neural lineages and iPSCs share suppressed translation and mitochondrial pathways and activate cellular stress responses. When XIST is induced before the neural progenitor stage, T21 dosage correction suppresses a pronounced skew toward astrogenesis in neural differentiation. Because our transgene remains inducible in postmitotic T21 neurons and astrocytes, we demonstrate that XIST efficiently represses genes even after terminal differentiation, which will empower exploration of cell type-specific T21 phenotypes that remain responsive to chr21 dosage.


Assuntos
Diferenciação Celular , Síndrome de Down , Dosagem de Genes , Células-Tronco Pluripotentes Induzidas , Neurogênese , RNA Longo não Codificante , Síndrome de Down/genética , Humanos , Neurogênese/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , RNA Longo não Codificante/genética , Diferenciação Celular/genética , Cromossomos Humanos Par 21/genética , Neurônios/metabolismo
5.
Org Biomol Chem ; 22(25): 5127-5133, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38847063

RESUMO

The synthesis of polyketide natural products has been a captivating pursuit in organic chemistry, with a particular focus on selectively introducing 1,3-polyol units. Among these natural products, Marinomycins A-D have garnered substantial interest due to their exceptional structural features and potent cytotoxicity. In this paper, we present a novel approach for synthesising the monomeric counterparts of Marinomycin A and B. Our method employs a previously established iterative cycle in conjunction with a standardised polyketide building block. Through this strategy, we showcase a promising pathway towards total and partial syntheses of these intriguing natural products.

6.
FEBS Open Bio ; 14(7): 1072-1086, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38702074

RESUMO

Telomerase activity is directly affected by the laminin receptor precursor (LRP) protein, a highly conserved nonintegrin transmembrane receptor, which has been shown to have therapeutic effects in ageing, and age-related diseases. Recently, it has been found that overexpression of LRP-FLAG, by plasmid transfection, leads to a significant increase in telomerase activity in cell culture models. This may indicate that upregulation of LRP can be used to treat various age-related diseases. However, transfection is not a viable treatment strategy for patients. Therefore, we present a nanoencapsulated protein-based drug synthesised using poly(lactic-co-glycolic acid) (PLGA) nanocapsules for delivery of the 37 kDa LRP protein therapeutic. PLGA nanocapsules were synthesised using the double emulsification-solvent evaporation technique. Different purification methods, including filtration and centrifugation, were tested to ensure that the nanocapsules were within the optimal size range, and the BCA assay was used to determine encapsulation efficiency. The completed drug was tested in a HEK-293 cell culture model, to investigate the effect on cell viability, LRP protein levels and telomerase activity. A significant increase in total LRP protein levels with a concomitant increase in cell viability and telomerase activity was observed. Due to the observed increase in telomerase activity, this approach could represent a safer alternative to plasmid transfection for the treatment of age-related diseases.


Assuntos
Sobrevivência Celular , Nanocápsulas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Humanos , Nanocápsulas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Células HEK293 , Sobrevivência Celular/efeitos dos fármacos , Proteínas Recombinantes , Telomerase/metabolismo , Telomerase/genética , Ácido Poliglicólico/química , Sistemas de Liberação de Medicamentos/métodos , Ácido Láctico/química , Receptores de Laminina/metabolismo , Receptores de Laminina/genética
7.
Eur J Immunol ; : e2350797, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778497

RESUMO

The expression of E-cadherin on Langerhans cells (LC) is required for adequate dendrite intercalation between epidermal keratinocytes. Upon disruption of epidermal homeostasis by tape stripping, E-cadherin competent LC extend dendrites reaching up to the epidermal surface, while E-cad deficient LC lack this ability.

8.
J Crit Care ; 83: 154831, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38797056

RESUMO

PURPOSE: To assess the prevalence and relevance of invasive fungal disease (IFD) during veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO). METHODS: Retrospective analysis from January 2013 to November 2023 of adult V-A ECMO cases at a German University Hospital. Parameters relating to IFD, demographics, length of stay (LoS), days on ECMO and mechanical ventilation, prognostic scores and survival were assessed. Multivariable logistic regression analyses with IFD and death as dependent variables were performed. Outcome was assessed after propensity score matching IFD-patients to non-IFD-controls. RESULTS: 421 patients received V-A ECMO. 392 patients with full electronic datasets were included. The prevalence of IFD, invasive candidiasis and probable invasive pulmonary aspergillosis was 4.6%, 3.8% and 1.0%. Severity of acute disease, pre-existing moderate-to-severe renal disease and continuous kidney replacement therapy were predictive of IFD. In-hospital mortality (94% (17/18) compared to 67% (252/374) in non-IFD patients (p = 0.0156)) was predicted by female sex, SOFA score at admission, SAVE score and IFD (for IFD: OR: 8.31; CI: 1.60-153.18; p: 0.044). There was no difference in outcome after matching IFD-cases to non-IFD-controls. CONCLUSIONS: IFD are detected in about one in 20 patients on V-A ECMO, indicating mortality >90%. However, IFD do not contribute to prognosis in this population.

9.
Bone Jt Open ; 5(4): 294-303, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38599585

RESUMO

Aims: Patients with proximal femoral fractures (PFFs) are often multimorbid, thus unplanned readmissions following surgery are common. We therefore aimed to analyze 30-day and one-year readmission rates, reasons for, and factors associated with, readmission risk in a cohort of patients with surgically treated PFFs across Austria. Methods: Data from 11,270 patients with PFFs, treated surgically (osteosyntheses, n = 6,435; endoprostheses, n = 4,835) at Austrian hospitals within a one-year period (January to December 2021) was retrieved from the Leistungsorientierte Krankenanstaltenfinanzierung (Achievement-Oriented Hospital Financing). The 30-day and one-year readmission rates were reported. Readmission risk for any complication, as well as general medicine-, internal medicine-, and surgery/injury-associated complications, and factors associated with readmissions, were investigated. Results: The 30-day and one-year readmission rates due to any complication were 15% and 47%, respectively. The 30-day readmission rate (p = 0.001) was higher in endoprosthesis than osteosynthesis patients; this was not the case for the one-year readmission rate (p = 0.138). Internal medicine- (n = 2,273 (20%)) and surgery/injury-associated complications (n = 1,612 (14%)) were the most common reason for one-year readmission. Regardless of the surgical procedure, male sex was significantly associated with higher readmission risk due to any, as well as internal medicine-associated, complication. Advanced age was significantly associated with higher readmission risk after osteosynthesis. In both cohorts, treatment at mid-sized hospitals was significantly associated with lower readmission risk due to any complication, while prolonged length of stay was associated with higher one-year readmission risks due to any complication, as well as internal-medicine associated complications. Conclusion: Future health policy decisions in Austria should focus on optimization of perioperative and post-discharge management of this vulnerable patient population.

10.
J Clin Med ; 13(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38592690

RESUMO

BACKGROUND: Our purpose was to evaluate whether the time of intervention and the type of meniscus surgery (repair vs. partial meniscectomy) play a role in managing anterior cruciate ligament (ACL) reconstructions with concurrent meniscus pathologies. METHODS: We performed a prospective cohort study which differentiated between early and late ACL reconstructions with a cut-off at 3 months. Patients were re-evaluated after 2 years. RESULTS: Thirty-nine patients received an operation between 2-12 weeks after the injury, and thirty patients received the surgery between 13-28 weeks after trauma. The strongest negative predictive factor of the International Knee Documentation Committee subjective knee form in a hierarchical regression model was older age (ß = -0.49 per year; 95% CI [-0.91; -0.07]; p = 0.022; partial R2 = 0.08)). The strongest positive predictive factor was a higher preoperative Tegner score (ß = 3.6; 95% CI [0.13; 7.1]; p = 0.042; partial R2 = 0.07) and an interaction between meniscus repair surgery and the time of intervention (ß = 27; 95% CI [1.6; 52]; p = 0.037; partial R2 = 0.07), revealing a clinical meaningful difference as to whether meniscus repairs were performed within 12 weeks after trauma or were delayed. There was no difference whether partial meniscectomy was performed early or delayed. CONCLUSIONS: Surgical timing plays a crucial role when surgeons opt for a meniscus repair rather than for a meniscectomy.

11.
Cell Mol Life Sci ; 81(1): 163, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38570362

RESUMO

Proteolytic release of transmembrane proteins from the cell surface, the so called ectodomain shedding, is a key process in inflammation. Inactive rhomboid 2 (iRhom2) plays a crucial role in this context, in that it guides maturation and function of the sheddase ADAM17 (a disintegrin and metalloproteinase 17) in immune cells, and, ultimately, its ability to release inflammatory mediators such as tumor necrosis factor α (TNFα). Yet, the macrophage sheddome of iRhom2/ADAM17, which is the collection of substrates that are released by the proteolytic complex, is only partly known. In this study, we applied high-resolution proteomics to murine and human iRhom2-deficient macrophages for a systematic identification of substrates, and therefore functions, of the iRhom2/ADAM17 proteolytic complex. We found that iRhom2 loss suppressed the release of a group of transmembrane proteins, including known (e.g. CSF1R) and putative novel ADAM17 substrates. In the latter group, shedding of major histocompatibility complex class I molecules (MHC-I) was consistently reduced in both murine and human macrophages when iRhom2 was ablated. Intriguingly, it emerged that in addition to its shedding, iRhom2 could also control surface expression of MHC-I by an undefined mechanism. We have demonstrated the biological significance of this process by using an in vitro model of CD8+ T-cell (CTL) activation. In this model, iRhom2 loss and consequent reduction of MHC-I expression on the cell surface of an Epstein-Barr virus (EBV)-transformed lymphoblastoid cell line dampened activation of autologous CTLs and their cell-mediated cytotoxicity. Taken together, this study uncovers a new role for iRhom2 in controlling cell surface levels of MHC-I by a dual mechanism that involves regulation of their surface expression and ectodomain shedding.


Assuntos
Proteínas de Transporte , Infecções por Vírus Epstein-Barr , Animais , Humanos , Camundongos , Proteína ADAM17/genética , Proteína ADAM17/metabolismo , Proteínas de Transporte/metabolismo , Herpesvirus Humano 4 , Complexo Principal de Histocompatibilidade , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Knockout
12.
Glob Chang Biol ; 30(5): e17276, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38683126

RESUMO

Boreal forests are frequently subjected to disturbances, including wildfire and clear-cutting. While these disturbances can cause soil carbon (C) losses, the long-term accumulation dynamics of soil C stocks during subsequent stand development is controlled by biological processes related to the balance of net primary production (NPP) and outputs via heterotrophic respiration and leaching, many of which remain poorly understood. We review the biological processes suggested to influence soil C accumulation in boreal forests. Our review indicates that median C accumulation rates following wildfire and clear-cutting are similar (0.15 and 0.20 Mg ha-1 year-1, respectively), however, variation between studies is extremely high. Further, while many individual studies show linear increases in soil C stocks through time after disturbance, there are indications that C stock recovery is fastest early to mid-succession (e.g. 15-80 years) and then slows as forests mature (e.g. >100 years). We indicate that the rapid build-up of soil C in younger stands appears not only driven by higher plant production, but also by a high rate of mycorrhizal hyphal production, and mycorrhizal suppression of saprotrophs. As stands mature, the balance between reductions in plant and mycorrhizal production, increasing plant litter recalcitrance, and ectomycorrhizal decomposers and saprotrophs have been highlighted as key controls on soil C accumulation rates. While some of these controls appear well understood (e.g. temporal patterns in NPP, changes in aboveground litter quality), many others remain research frontiers. Notably, very little data exists describing and comparing successional patterns of root production, mycorrhizal functional traits, mycorrhizal-saprotroph interactions, or C outputs via heterotrophic respiration and dissolved organic C following different disturbances. We argue that these less frequently described controls require attention, as they will be key not only for understanding ecosystem C balances, but also for representing these dynamics more accurately in soil organic C and Earth system models.


Assuntos
Carbono , Solo , Taiga , Incêndios Florestais , Solo/química , Carbono/metabolismo , Carbono/análise , Florestas , Micorrizas/fisiologia , Microbiologia do Solo , Agricultura Florestal
13.
J Craniomaxillofac Surg ; 52(5): 644-651, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38582672

RESUMO

This study investigated the natural course of cemento-osseous dysplasia (COD) on cone-beam computed tomography (CBCT). Retrospectively, 104 CBCT scans from 36 patients (mean age, 44.5 years; 33 female and three male) with mandibular COD (10 florid, seven focal, 19 periapical) were included, based upon clinico-radiological features, without complications such as infection and related surgery. Changes in maximum diameter and morphology (lytic, mixed lytic-sclerotic, sclerotic) were evaluated in 83 lesions, with a mean follow-up of 28.3 months. The occurrence of a diameter increase was assessed by time-to-event analysis; interreader agreement for diameter and morphological evaluation by intraclass correlation coefficient and weighted κ statistics, respectively. Fifteen of 83 (18.1%) lesions (eight florid, one focal, six periapical) in 10 patients increased in diameter; 12 of 83 (14.5%) lesions (five florid, seven periapical) in 11 patients changed morphologically. The median period until a diameter increase was longest (120 months) for periapical COD, and shortest (66 months) for florid COD (p = 0.023). There was high reader agreement (ICC = 0.891; weighted κ = 0.901). In conclusion, CBCT is an effective tool with which to follow-up COD. If any, the natural progress in uncomplicated COD is prolonged, which underlines its non-surgical character and aids in its long-term management.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Feminino , Masculino , Adulto , Estudos Retrospectivos , Pessoa de Meia-Idade , Seguimentos , Cementoma/diagnóstico por imagem , Idoso , Adolescente , Adulto Jovem , Doenças Mandibulares/diagnóstico por imagem
14.
PLoS One ; 19(3): e0300739, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38547245

RESUMO

INTRODUCTION: An increasing amount of longitudinal health data is available on critically ill septic patients in the age of digital medicine, including daily sequential organ failure assessment (SOFA) score measurements. Thus, the assessment in sepsis focuses increasingly on the evaluation of the individual disease's trajectory. Machine learning (ML) algorithms may provide a promising approach here to improve the evaluation of daily SOFA score dynamics. We tested whether ML algorithms can outperform the conventional ΔSOFA score regarding the accuracy of 30-day mortality prediction. METHODS: We used the multicentric SepsisDataNet.NRW study cohort that prospectively enrolled 252 sepsis patients between 03/2018 and 09/2019 for training ML algorithms, i.e. support vector machine (SVM) with polynomial kernel and artificial neural network (aNN). We used the Amsterdam UMC database covering 1,790 sepsis patients for external and independent validation. RESULTS: Both SVM (AUC 0.84; 95% CI: 0.71-0.96) and aNN (AUC 0.82; 95% CI: 0.69-0.95) assessing the SOFA scores of the first seven days led to a more accurate prognosis of 30-day mortality compared to the ΔSOFA score between day 1 and 7 (AUC 0.73; 95% CI: 0.65-0.80; p = 0.02 and p = 0.05, respectively). These differences were even more prominent the shorter the time interval considered. Using the SOFA scores of day 1 to 3 SVM (AUC 0.82; 95% CI: 0.68 0.95) and aNN (AUC 0.80; 95% CI: 0.660.93) led to a more accurate prognosis of 30-day mortality compared to the ΔSOFA score (AUC 0.66; 95% CI: 0.58-0.74; p < 0.01 and p < 0.01, respectively). Strikingly, all these findings could be confirmed in the independent external validation cohort. CONCLUSIONS: The ML-based algorithms using daily SOFA scores markedly improved the accuracy of mortality compared to the conventional ΔSOFA score. Therefore, this approach could provide a promising and automated approach to assess the individual disease trajectory in sepsis. These findings reflect the potential of incorporating ML algorithms as robust and generalizable support tools on intensive care units.


Assuntos
Escores de Disfunção Orgânica , Sepse , Humanos , Estudos Retrospectivos , Unidades de Terapia Intensiva , Aprendizado de Máquina , Sepse/diagnóstico , Prognóstico , Curva ROC
15.
Nat Aging ; 4(4): 595-612, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519806

RESUMO

Age-related decline in brain endothelial cell (BEC) function contributes critically to neurological disease. Comprehensive atlases of the BEC transcriptome have become available, but results from proteomic profiling are lacking. To gain insights into endothelial pathways affected by aging, we developed a magnetic-activated cell sorting-based mouse BEC enrichment protocol compatible with proteomics and resolved the profiles of protein abundance changes during aging. Unsupervised cluster analysis revealed a segregation of age-related protein dynamics with biological functions, including a downregulation of vesicle-mediated transport. We found a dysregulation of key regulators of endocytosis and receptor recycling (most prominently Arf6), macropinocytosis and lysosomal degradation. In gene deletion and overexpression experiments, Arf6 affected endocytosis pathways in endothelial cells. Our approach uncovered changes not picked up by transcriptomic studies, such as accumulation of vesicle cargo and receptor ligands, including Apoe. Proteomic analysis of BECs from Apoe-deficient mice revealed a signature of accelerated aging. Our findings provide a resource for analysing BEC function during aging.


Assuntos
Células Endoteliais , Proteômica , Camundongos , Animais , Células Endoteliais/metabolismo , Proteômica/métodos , Encéfalo/metabolismo , Endotélio/metabolismo , Apolipoproteínas E/metabolismo
16.
J Innate Immun ; 16(1): 226-247, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38527452

RESUMO

INTRODUCTION: While TLR ligands derived from microbial flora and pathogens are important activators of the innate immune system, a variety of factors such as intracellular bacteria, viruses, and parasites can induce a state of hyperreactivity, causing a dysregulated and potentially life-threatening cytokine over-response upon TLR ligand exposure. Type I interferon (IFN-αß) is a central mediator in the induction of hypersensitivity and is strongly expressed in splenic conventional dendritic cells (cDC) and marginal zone macrophages (MZM) when mice are infected with adenovirus. This study investigates the ability of adenoviral infection to influence the activation state of the immune system and underlines the importance of considering this state when planning the treatment of patients. METHODS: Infection with adenovirus-based vectors (Ad) or pretreatment with recombinant IFN-ß was used as a model to study hypersensitivity to lipopolysaccharide (LPS) in mice, murine macrophages, and human blood samples. The TNF-α, IL-6, IFN-αß, and IL-10 responses induced by LPS after pretreatment were measured. Mouse knockout models for MARCO, IFN-αßR, CD14, IRF3, and IRF7 were used to probe the mechanisms of the hypersensitive reaction. RESULTS: We show that, similar to TNF-α and IL-6 but not IL-10, the induction of IFN-αß by LPS increases strongly after Ad infection. This is true both in mice and in human blood samples ex vivo, suggesting that the regulatory mechanisms seen in the mouse are also present in humans. In mice, the scavenger receptor MARCO on IFN-αß-producing cDC and splenic marginal zone macrophages is important for Ad uptake and subsequent cytokine overproduction by LPS. Interestingly, not all IFN-αß-pretreated macrophage types exposed to LPS exhibit an enhanced TNF-α and IL-6 response. Pretreated alveolar macrophages and alveolar macrophage-like murine cell lines (MPI cells) show enhanced responses, while bone marrow-derived and peritoneal macrophages show a weaker response. This correlates with the respective absence or presence of the anti-inflammatory IL-10 response in these different macrophage types. In contrast, Ad or IFN-ß pretreatment enhances the subsequent induction of IFN-αß in all macrophage types. IRF3 is dispensable for the LPS-induced IFN-αß overproduction in infected MPI cells and partly dispensable in infected mice, while IRF7 is required. The expression of the LPS co-receptor CD14 is important but not absolutely required for the elicitation of a TNF-α over-response to LPS in Ad-infected mice. CONCLUSION: Viral infections or application of virus-based vaccines induces type I interferon and can tip the balance of the innate immune system in the direction of hyperreactivity to a subsequent exposure to TLR ligands. The adenoviral model presented here is one example of how multiple factors, both environmental and genetic, affect the physiological responses to pathogens. Being able to measure the current reactivity state of the immune system would have important benefits for infection-specific therapies and for the prevention of vaccination-elicited adverse effects.


Assuntos
Adenoviridae , Citocinas , Fator Regulador 3 de Interferon , Lipopolissacarídeos , Macrófagos , Camundongos Knockout , Animais , Camundongos , Lipopolissacarídeos/imunologia , Humanos , Fator Regulador 3 de Interferon/metabolismo , Fator Regulador 3 de Interferon/genética , Macrófagos/imunologia , Citocinas/metabolismo , Camundongos Endogâmicos C57BL , Fator Regulador 7 de Interferon/metabolismo , Fator Regulador 7 de Interferon/genética , Vetores Genéticos , Infecções por Adenoviridae/imunologia , Interferon Tipo I/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Receptor de Interferon alfa e beta/genética , Receptor de Interferon alfa e beta/metabolismo , Células Cultivadas , Células Dendríticas/imunologia , Interferon beta/metabolismo
17.
J Bodyw Mov Ther ; 37: 344-349, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38432827

RESUMO

BACKGROUND: Soccer is one of the most popular sports with millions of active professional and non-professional players worldwide. Traumatic hip dislocations are rare in soccer but can lead to major sequelae both physically and psychologically. The aim of this review was to obtain insight into the outcomes after surgerically repaired hip fracture-dislocation in soccer players as well as rehabilitation and prevention. METHODS: Two cases of a posterior hip fracture-dislocation that occurred during an amateur soccer match are presented and mechanism of injury, complications and rehabilitation were analysed. Follow-up of both patients was at least one year after surgery. Questionnaires and physical examinations were obtained to quantify and qualify outcome. RESULTS: In both cases the hip-dislocations were reduced within 3 h after injury. Semi-elective open reduction and internal fixation was performed within seven days. In one case, there was a concomitant Pipkin fracture and sciatic nerve neuropathy. There were no postoperative complications. Follow-up showed full of range of motion and normal hip functionality in both cases. However, both patients indicated a reduced quality of life and anxiety related to the accident. CONCLUSION: Traumatic hip fracture-dislocations during soccer practice are extremely rare. Despite uncomplicated fracture healing after surgery and return of hip function, both patients still suffer from psychological problems resulting in a decreased quality of life. Further research is required to enhance psychological outcomes, as well as to facilitate return to pre-injury levels of participation and engagement in sports following traumatic hip fracture-dislocations related to soccer.


Assuntos
Luxação do Quadril , Fraturas do Quadril , Futebol , Esportes , Humanos , Luxação do Quadril/etiologia , Luxação do Quadril/cirurgia , Fraturas do Quadril/cirurgia , Qualidade de Vida
18.
Clin Exp Rheumatol ; 42(1): 10-14, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38306018

RESUMO

OBJECTIVES: Sidekick Health launched a 16-week digital support programme for people with rheumatoid arthritis in 2021. The objective of this retrospective analysis was to understand whether quality of life (QoL; sleep quality, energy and stress levels) improved for users engaged with the programme in a real-world setting. METHODS: This analysis included 635 users who engaged with the programme after the first week, out of 1541 who enrolled. Users self-reported QoL up to four times per week on their phones. Survival bias was investigated by comparing pre-post QoL scores of the full analysis set (all users) and the complete case set (programme completers). Users were divided into highly-engaged and less-engaged groups based on the weekly average number of in-app activities by iterative K-means clustering. Mixed models for repeated measures were used to estimate changes in QoL for highly-versus less-engaged groups. RESULTS: Both the full analysis set and the complete case set had significant pre-post improvements in energy and stress; this suggested that survival bias did not have a substantial effect on these real-world data. Both the highly- and less-engaged groups experienced significant longitudinal improvements in all QoL outcomes. Highly-engaged users achieved better scores in energy, stress, and sleep than less-engaged users. Moreover, a significant time-group interaction for sleep showed that highly-engaged users not only had better sleep scores, but also experienced larger improvements over time than less-engaged users. CONCLUSIONS: These findings demonstrate that a 16-week digital support programme improves self-reported QoL measures, supporting the 2021 EULAR recommendations to incorporate digital healthcare into routine practice. Noteworthy is the study's relevance in the context of the increasing importance of patient empowerment in managing chronic diseases.


Assuntos
Artrite Reumatoide , Qualidade de Vida , Humanos , Saúde Digital , Estudos Retrospectivos , Doença Crônica , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/terapia
19.
Chemistry ; 30(20): e202304011, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38334293

RESUMO

One of the most useful transformations in the synthetic chemist arsenal is the oxidation of alcohols to their corresponding carbonyl congeners. Despite its seemingly straightforward nature, this transformative reaction predominantly relies on the use of metals or hazardous reagents, making these processes highly unsustainable. To address this challenge, we have developed a sustainable metal-free method for the oxidation of alcohols in continuous flow. Using a solid phase hypervalent iodine catalyst and nBu4HSO5 as a phase transfer catalyst and co-oxidant, primary and secondary alcohols were selectively oxidized to the corresponding carbonyl motifs. This operationally simple continuous-flow set-up is highly robust (15 cycles run without significant catalyst leaching or loss of reaction efficiency), uses green solvents, such as acetonitrile or acetic acid, and is readily scalable.

20.
J Autoimmun ; 143: 103168, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38350168

RESUMO

OBJECTIVE: Altered B cell receptor (BCR) signaling has been implicated in the pathogenesis of rheumatoid arthritis (RA). Here we aimed to identify signaling aberrations in autoantibody-positive and autoantibody-negative RA patients by performing a comprehensive analysis of the BCR signaling cascade in different B cell subsets. METHODS: We first optimized phosphoflow cytometry for an in-depth analysis of BCR signaling across immunoglobulin isotypes in healthy donors. Subsequently, we compared BCR signaling in circulating B cell subsets from treatment-naïve, newly-diagnosed autoantibody-positive RA and autoantibody-negative RA patients and healthy controls (HCs). RESULTS: We observed subset-specific phosphorylation patterns of the BCR signalosome in circulating B cells from healthy donors. Compared with HCs, autoantibody-positive RA patients displayed enhanced responses to BCR stimulation for multiple signaling proteins, specifically in naïve and IgA+ memory B cells. Whereas in unstimulated healthy donor B cells, the phosphorylation status of individual signaling proteins showed only limited correlation, BCR stimulation enhanced the interconnectivity in phosphorylation within the BCR signalosome. However, this strong interconnectivity within the BCR signalosome in stimulated B cells from HCs was lost in RA, especially in autoantibody-positive RA patients. Finally, we observed strong correlations between SYK and BTK protein expression, and IgA and IgG anti-citrullinated protein antibody concentrations in serum from autoantibody-positive RA patients. CONCLUSION: Collectively, the isotype-specific analysis of multiple key components of the BCR signalosome identified aberrant BCR signaling responses in treatment-naïve autoantibody-positive RA patients, particularly in naïve B cells and IgA+ memory B cells. Our findings support differential involvement of dysregulated BCR signaling in the pathogenesis of autoantibody-positive and autoantibody-negative RA.


Assuntos
Artrite Reumatoide , Autoanticorpos , Humanos , Células B de Memória , Isotipos de Imunoglobulinas , Receptores de Antígenos de Linfócitos B , Imunoglobulina A
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