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31.

Purpose

With increasing resistance of microorganisms to antibiotics, photodynamic inactivation (PDI) may also be a potential therapeutic option in infectious keratitis. As part of the inflammatory response in infectious keratitis, keratocytes produce various interleukins. The purpose of this study was to evaluate the potential anti-inflammatory effect of PDI, analyzing interleukin-1 alpha (IL-1α), interleukine-1 beta (IL-1β), interleukin-6 (IL-6), and interleukin-8 (IL-8) secretion of human keratocytes following PDI, in vitro.

Methods

Primary human keratocytes were isolated by digestion in collagenase A (1.0 mg/ml) from human corneal buttons, and cultured in DMEM/Ham’s F12 medium supplemented with 10 % FCS. Keratocyte cell cultures underwent illumination using red (670 nm) light for 13 min following exposure to 100 nM concentration of the photosensitizer chlorin e6 (Ce6) in the culture medium. Five and 24 hours after PDI, secretion of IL-1α, IL-1β, IL-6, and IL-8 was measured by enzyme-linked immunoabsorbent assay (ELISA).

Results

The secretion of IL-1α was under the measurement limit in treated and untreated cell cultures 5 and 24 h after PDI. Compared to untreated controls, IL-6 and IL-8 secretion of keratocytes decreased (p?<?0.05 and 0.0001) significantly 5 hours after PDI, whereas IL-1β secretion remained unchanged. Twenty-four hours after PDI, secretion of IL-1β, IL-6, and IL-8 did not differ significantly from untreated controls.

Conclusions

In the short term, PDI does not have an impact on IL-1α and IL-1β secretion of keratocytes, in vitro. Photodynamic inactivation inhibits IL-6 and IL-8 secretion of keratocytes transiently (5 h), which normalizes 24 h following treatment. Through the short-term impact of chlorine e6-PDI on IL-6 and IL-8 secretion, PDI may inhibit the inflammatory cascade in at least keratocyte cultures.  相似文献   
32.
BackgroundMeta-analyses of randomized controlled trials have suggested an increased long-term mortality risk following femoropopliteal and infrapopliteal angioplasty using paclitaxel-coated devices. This study was conducted to evaluate long-term mortality after paclitaxel drug-coated balloon (DCB) and plain old balloon angioplasty (POBA) of infrapopliteal lesions in real-world practice.MethodsA retrospective mortality analysis of patients with at least 3 years of follow-up who underwent balloon-based endovascular therapy of infrapopliteal lesions was performed.ResultsOverall, 2,424 patients with infrapopliteal lesions were treated within the study period. Five hundred seventy-six patients fulfilled the study criteria. Of those, 269 patients were treated with uncoated devices without crossover to a paclitaxel-coated device during follow-up and 307 patients with DCB angioplasty. Mean (SD) follow-up was 46.48 (32.77) months. The mortality rate was 66.9% after POBA and 46.9% after DCB (P < .001). In the matched-pair cohort, 164 patients died after uncoated treatment (66.7%), and 119 in the DCB group died (48.4%; P < .001). There was no correlation between DCB length and mortality rate (P = .357). For the entire cohort, multivariate logistic regression analysis showed type of treatment (uncoated device vs DCB; P = .002), age (P < .001), stroke (P = .005), renal insufficiency (P = .014), and critical limb ischemia (P = .001) to be independent predictors of all-cause mortality. There was no significant difference in mortality among the paclitaxel exposure groups.ConclusionIn this real-world retrospective analysis, the long-term mortality rate was lower after DCB angioplasty than after POBA of infrapopliteal lesions.  相似文献   
33.
The treatment of patients with early stage breast cancer has changed in recent years due to the introduction of pembrolizumab, olaparib, and abemaciclib. These and other drugs with the same class of active ingredient are currently in trial for various indications. This review article summarizes the latest results that have either been presented at major conferences such as the ESMO 2022 or published recently in international journals. This includes reports on newly discovered breast cancer genes, atezolizumab in neoadjuvant therapy in HER2-positive patients, long-term data from the APHINITY study, and on how preoperative peritumoral application of local anesthetics can influence the prognosis. We also present solid data on dynamic Ki-67 from the ADAPT studies.Key words: breast cancer, surgery, chemotherapy, therapy standard  相似文献   
34.
ObjectiveFederated learning (FL) allows multiple distributed data holders to collaboratively learn a shared model without data sharing. However, individual health system data are heterogeneous. “Personalized” FL variations have been developed to counter data heterogeneity, but few have been evaluated using real-world healthcare data. The purpose of this study is to investigate the performance of a single-site versus a 3-client federated model using a previously described Coronavirus Disease 19 (COVID-19) diagnostic model. Additionally, to investigate the effect of system heterogeneity, we evaluate the performance of 4 FL variations.Materials and methodsWe leverage a FL healthcare collaborative including data from 5 international healthcare systems (US and Europe) encompassing 42 hospitals. We implemented a COVID-19 computer vision diagnosis system using the Federated Averaging (FedAvg) algorithm implemented on Clara Train SDK 4.0. To study the effect of data heterogeneity, training data was pooled from 3 systems locally and federation was simulated. We compared a centralized/pooled model, versus FedAvg, and 3 personalized FL variations (FedProx, FedBN, and FedAMP).ResultsWe observed comparable model performance with respect to internal validation (local model: AUROC 0.94 vs FedAvg: 0.95, P = .5) and improved model generalizability with the FedAvg model (P < .05). When investigating the effects of model heterogeneity, we observed poor performance with FedAvg on internal validation as compared to personalized FL algorithms. FedAvg did have improved generalizability compared to personalized FL algorithms. On average, FedBN had the best rank performance on internal and external validation.ConclusionFedAvg can significantly improve the generalization of the model compared to other personalization FL algorithms; however, at the cost of poor internal validity. Personalized FL may offer an opportunity to develop both internal and externally validated algorithms.  相似文献   
35.
In certain instances, Th17 responses are associated with severe immunopathology. T cell–intrinsic mechanisms that restrict pathogenic effector functions have been described for type 1 and 2 responses but are less well studied for Th17 cells. Here, we report a cell-intrinsic feedback mechanism that controls the pathogenicity of Th17 cells. Th17 cells produce IL-24, which prompts them to secrete IL-10. The IL-10–inducing function of IL-24 is independent of the cell surface receptor of IL-24 on Th17 cells. Rather, IL-24 is recruited to the inner mitochondrial membrane, where it interacts with the NADH dehydrogenase (ubiquinone) 1 α subcomplex subunit 13 (also known as Grim19), a constituent of complex I of the respiratory chain. Together, Grim19 and IL-24 promote the accumulation of STAT3 in the mitochondrial compartment. We propose that IL-24–guided mitochondrial STAT3 constitutes a rheostat to blunt extensive STAT3 deflections in the nucleus, which might then contribute to a robust IL-10 response in Th17 cells and a restriction of immunopathology in experimental autoimmune encephalomyelitis.  相似文献   
36.
PurposeEvaluation of mRNA and microRNA (miRNA) expression in epithelium and stroma of patients with keratoconus.MethodsThe epithelium and stroma of eight corneas of eight patients with keratoconus and eight corneas of eight non-keratoconus healthy controls were studied separately. RNA was extracted, and mRNA and miRNA analyses were performed using microarrays. Differentially expressed mRNAs and miRNAs in epithelial and stromal keratoconus samples compared to healthy controls were identified. Selected genes and miRNAs were further validated using RT-qPCR.ResultsWe discovered 170 epithelial and 1498 stromal deregulated protein-coding mRNAs in KC samples. In addition, in epithelial samples 180 miRNAs and in stromal samples 379 miRNAs were significantly deregulated more than twofold compared to controls. Pathway analysis revealed enrichment of metabolic and axon guidance pathways for epithelial cells and enrichment of metabolic, mitogen-activated protein kinase (MAPK), and focal adhesion pathways for stromal cells.ConclusionsThis study demonstrates significant differences in the expression and regulation of mRNAs and miRNAs in the epithelium and stroma of Patients with KC. Also, in addition to the well-known target candidates, we were able to identify further genes and miRNAs that may be associated with keratoconus. Signaling pathways influencing metabolic changes and cell contacts are affected in epithelial and stromal cells of patients with keratoconus.  相似文献   
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40.

Purpose  

To compare two different approaches to performing focus groups and individual interviews, an open approach, and an approach based on the International Classification of Functioning, Disability and Health (ICF).  相似文献   
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