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The use of machine learning models to predict clinical outcomes from (longitudinal) electronic health record (EHR) data is becoming increasingly popular due to advances in deep architectures, representation learning, and the growing availability of large EHR datasets. Existing models generally assume access to the same data sources during both training and inference stages. However, this assumption is often challenged by the fact that real-world clinical datasets originate from various data sources (with distinct sets of covariates), which though can be available for training (in a research or retrospective setting), are more realistically only partially available (a subset of such sets) for inference when deployed. So motivated, we introduce Contrastive Learning for clinical Outcome Prediction with Partial data Sources (CLOPPS), that trains encoders to capture information across different data sources and then leverages them to build classifiers restricting access to a single data source. This approach can be used with existing cross-sectional or longitudinal outcome classification models. We present experiments on two real-world datasets demonstrating that CLOPPS consistently outperforms strong baselines in several practical scenarios.
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Atomically thin transition metal dichalcogenides (TMDS) offer a promising route to the scaling down of optoelectronic devices to the ultimate thickness limit. But the weak light-matter interaction caused by their atomically thin nature makes them inevitably rely on external photonic structures to enhance optical absorption. Here, we report chiral absorption enhancement in atomically thin tungsten diselenide (WSe2) using chiral resonances in photonic crystal (PhC) nanostructures patterned directly in WSe2 itself. We show that the quality factors (Q factors) of the resonances grow exponentially as the PhC thickness approaches atomic limit. As such, the strong interaction of high Q factor photonic resonance with the coexisting exciton resonance in WSe2 results into self-coupled exciton-polaritons. By balancing the light coupling and absorption rates, the incident light can critically couple to chiral resonances in WSe2 PhC exciton-polaritons, leading to the theoretically limited 50% optical absorptance with over 84% circular dichroism (CD).
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BACKGROUND: Per- and polyfluoroalkyl Substances (PFAS) are synthetic chemicals widely detected in humans and the environment. Exposure to perfluorooctanesulfonic acid (PFOS) or perfluorohexanesulfonic acid (PFHxS) was previously shown to cause dark-phase hyperactivity in larval zebrafish. OBJECTIVES: The objective of this study was to elucidate the mechanism by which PFOS or PFHxS exposure caused hyperactivity in larval zebrafish. METHODS: Swimming behavior was assessed in 5-d postfertilization (dpf) larvae following developmental (1-4 dpf) or acute (5 dpf) exposure to 0.43-7.86µM PFOS, 7.87-120µM PFHxS, or 0.4% dimethyl sulfoxide (DMSO). After developmental exposure and chemical washout at 4 dpf, behavior was also assessed at 5-8 dpf. RNA sequencing was used to identify differences in global gene expression to perform transcriptomic benchmark concentration-response (BMCT) modeling, and predict upstream regulators in PFOS- or PFHxS-exposed larvae. CRISPR/Cas9-based gene editing was used to knockdown peroxisome proliferator-activated receptors (ppars) pparaa/ab, pparda/db, or pparg at day 0. Knockdown crispants were exposed to 7.86µM PFOS or 0.4% DMSO from 1-4 dpf and behavior was assessed at 5 dpf. Coexposure with the ppard antagonist GSK3787 and PFOS was also performed. RESULTS: Transient dark-phase hyperactivity occurred following developmental or acute exposure to PFOS or PFHxS, relative to the DMSO control. In contrast, visual startle response (VSR) hyperactivity only occurred following developmental exposure and was irreversible up to 8 dpf. Similar global transcriptomic profiles, BMCT estimates, and enriched functions were observed in PFOS- and PFHxS-exposed larvae, and ppars were identified as putative upstream regulators. Knockdown of pparda/db, but not pparaa/ab or pparg, blunted PFOS-dependent VSR hyperactivity to control levels. This finding was confirmed via antagonism of ppard in PFOS-exposed larvae. DISCUSSION: This work identifies a novel adverse outcome pathway for VSR hyperactivity in larval zebrafish. We demonstrate that developmental, but not acute, exposure to PFOS triggered persistent VSR hyperactivity that required ppard function. https://doi.org/10.1289/EHP13667.
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Fluorocarbonos , Larva , Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Fluorocarbonos/toxicidade , Larva/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Receptores Ativados por Proliferador de Peroxissomo/genética , Ácidos Alcanossulfônicos/toxicidade , Reflexo de Sobressalto/efeitos dos fármacos , Ácidos Sulfônicos/toxicidade , NataçãoRESUMO
BACKGROUND: Craniofacial skeletal deformities can be addressed by applying tensile force to sutures to prompt sutural bone formation. The intricate process of mechanical modulation in craniofacial sutures involves complex biomechanical signal transduction. The small GTPase Ras homolog gene family member A (RhoA) functions as a key mechanotransduction protein, orchestrating the dynamic assembly of the cytoskeleton by activating the Rho-associated coiled-coil containing protein kinase (ROCK). Transcriptional coactivator with PDZ-binding motif (TAZ) serves as a crucial mediator in the regulation of genes and the orchestration of biological functions within the mechanotransduction signaling pathway. However, the role of RhoA/ROCK-TAZ in trans-sutural distraction osteogenesis has not been reported. METHODS: We utilized pre-osteoblast-specific RhoA deletion mice to establish an in vivo calvarial trans-sutural distraction model and an in vitro mechanical stretch model for pre-osteoblasts isolated from neonatal mice. Micro-CT and histological staining were utilized to detect the formation of new bone in the sagittal suture of the skull as well as the activation of RhoA, Osterix and TAZ. The activation of ROCK-limk-cofilin and the nuclear translocation of TAZ in pre-osteoblasts under mechanical tension were detected through Western blot, qRT-PCR, and immunofluorescence. RESULTS: The osteogenic differentiation of pre-osteoblasts was facilitated by mechanical tension through the activation of RhoA and Rho-associated kinase (ROCK), while ablation of RhoA impaired osteogenesis by inhibiting pre-osteoblast differentiation after suture expansion. Furthermore, inhibiting RhoA expression could block tensile-stimulated nuclear translocation of TAZ by preventing F-actin assembly through ROCK-LIM-domain kinase (LIMK)-cofilin pathway. In addition, the TAZ agonist TM-25659 could attenuate impaired osteogenesis caused by ablation of RhoA in pre-osteoblasts by increasing TAZ nuclear accumulation. CONCLUSIONS: This study demonstrates that mechanical stretching promotes the osteogenic differentiation of pre-osteoblasts in trans-sutural distraction osteogenesis, and this process is mediated by the RhoA/ROCK-TAZ signaling axis. Overall, our results may provide an insight for potential treatment strategies for craniosynostosis patients through trans-sutural distraction osteogenesis.
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Osteogênese por Distração , Osteogênese , Crânio , Quinases Associadas a rho , Proteína rhoA de Ligação ao GTP , Animais , Proteína rhoA de Ligação ao GTP/metabolismo , Quinases Associadas a rho/metabolismo , Camundongos , Crânio/metabolismo , Osteoblastos/metabolismo , Osteoblastos/citologia , Diferenciação Celular , Transdução de Sinais , Mecanotransdução Celular , Suturas Cranianas/metabolismo , Fator de Transcrição Sp7/metabolismo , Fator de Transcrição Sp7/genética , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteínas Adaptadoras de Transdução de SinalRESUMO
Dielectric phase gradient metasurfaces have emerged as promising candidates to shrink bulky optical elements to subwavelength thickness scale based on dielectric meta-atoms. These meta-atoms strongly interact with light, thus offering excellent phase manipulation of incident light. However, to fulfill 2π phase control using meta-atoms, the metasurface thickness, to date, is limited to the order of 102 nm. Here, we present the thickness scaling down of phase gradient metasurfaces to <λ/20 by using excitonic van der Waals metasurfaces. High-refractive-index enabled by exciton resonances and symmetry-breaking nanostructures in the patterned layered tungsten disulfide (WS2) corporately enable quasibound states in the continuum in WS2 metasurfaces, which consequently yield complete phase regulation of 2π with the thickness down to 35 nm. To illustrate the concept, we have experimentally demonstrated beam steering, focusing, and holographic display using WS2 metasurfaces. We envision our results unveiling new venues for ultimate thin phase gradient metasurfaces.
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Owing to their strong exciton effects and valley polarization properties, monolayer transition-metal dichalcogenides (1L TMDs) have unfolded the prospects of spin-polarized light-emitting devices. However, the wavefront control of exciton emission, which is critical to generate structured optical fields, remains elusive. In this work, the experimental demonstration of spin-locked vortex emission from monolayer Tungsten Disulfide (1L WS2) integrated with Silicon Nitride (SiNx) PhC slabs is presented. The symmetry-protected bound states in the continuum (BIC) in the SiNx PhC slabs engender azimuthal polarization field distribution in the momentum space with a topological singularity in the center of the Brillouin zone, which imposes the resonantly enhanced WS2 exciton emission with a spin-correlated spiral phase front by taking advantage of the winding topologies of resonances with the assistance of geometric phase scheme. As a result, exciton emission from 1L WS2 exhibits helical wavefront and doughnut-shaped intensity beam profile in the momentum space with topological charges locked to the spins of light. This strategy on spin-dependent excitonic vortex emission may offer the unparalleled capability of valley-polarized structured light generation for 1L TMDs.
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BACKGROUND: Small extracellular vesicles derived from milk (Milk-sEVs) have the advantages of easy availability, low cost, low toxicity, and inhibition of inflammation. CD36 mediates inflammation stress in a variety of disease states. The purpose of this study was to investigate the role of Milk-sEVs in inhibiting fibroblast inflammation through CD36 and provide reference data for the treatment of chronic apical periodontitis. RESULTS: The addition of Milk-sEVs resulted in decreased expression of inflammation-related factors in L929 cells, and transcriptome sequencing screened for the DEG CD36 in the Milk-sEV treatment group under inflammation. The mouse model of apical periodontitis was successfully established, and CD36 expression increased with the development of inflammation. Transfection of si-CD36 into L929 cells reduced inflammation by inhibiting activation of the MAPK signaling pathway. CONCLUSIONS: CD36 expression increased with the development of apical periodontitis. In the setting of LPS-mediated inflammation, Milk-sEVs inhibited activation of the MAPK signaling pathway by decreasing the expression of CD36 in L929 cells and thereby reducing inflammation.
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Antígenos CD36 , Vesículas Extracelulares , Sistema de Sinalização das MAP Quinases , Leite , Periodontite Periapical , Animais , Antígenos CD36/metabolismo , Antígenos CD36/genética , Vesículas Extracelulares/metabolismo , Camundongos , Leite/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Periodontite Periapical/metabolismo , Periodontite Periapical/patologia , Linhagem Celular , Modelos Animais de Doenças , Inflamação/metabolismo , Inflamação/patologia , MasculinoRESUMO
Objective: To investigate the structure, composition, and functions of the gut microbiota in elderly patients with hyperlipidemia. Methods: Sixteen older patients diagnosed with hyperlipidemia (M group) and 10 healthy, age-matched normal volunteers (N group) were included. These groups were further subdivided by sex into the male normal (NM, n = 5), female normal (NF, n = 5), male hyperlipidemia (MM, n = 8), and female hyperlipidemia (MF, n = 8) subgroups. Stool samples were collected for high-throughput sequencing of 16S rRNA genes. Blood samples were collected for clinical biochemical index testing. Results: Alpha- and beta-diversity analyses revealed that the structure and composition of the gut microbiota were significantly different between the M and N groups. The relative abundances of Bacteroides, Parabacteroides, Blautia, Peptococcus, and Bifidobacterium were significantly decreased, while those of Lactobacillus, Helicobacter, and Desulfovibrio were significantly higher in the M group. There were also significant sex-related differences in microbial structure between the NM and NF groups, and between the MM and MF groups. Through functional prediction with PICRUSt 2, we observed distinct between-group variations in metabolic pathways associated with the gut microbiota and their impact on the functionality of the nervous system. Pearson's correlation coefficient was used as a distance metric to build co-abundance networks. A hypergeometric test was used to detect taxonomies with significant enrichment in specific clusters. We speculated that modules with Muribaculaceae and Lachnospiraceae as the core microbes play an important ecological role in the intestinal microbiota of the M group. The relative intestinal abundances of Agathobacter and Faecalibacterium in the M group were positively correlated with serum triglyceride and low-density lipoprotein levels, while the relative abundance of Bifidobacterium was negatively correlated with the serum lipoprotein a level.
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Bactérias , Fezes , Microbioma Gastrointestinal , Hiperlipidemias , RNA Ribossômico 16S , Humanos , Microbioma Gastrointestinal/genética , Masculino , Feminino , Idoso , Hiperlipidemias/microbiologia , RNA Ribossômico 16S/genética , Fezes/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Pessoa de Meia-Idade , Idoso de 80 Anos ou maisRESUMO
Sequential catalysis by ent-copalyl diphosphate(CPS) and ent-kaurene synthase(KS) is a critical step for plants to initiate the biosynthesis of gibberellin with geranylgeranyl pyrophosphate(GGPP) as the substrate. This study mined the transcriptome data of Stellera chamaejasme and cloned two key diterpene synthase genes, SchCPS and SchKS, involved in the gibberellin pathway. The two genes had the complete open reading frames of 2 595 bp and 1 701 bp, encoding two hydrophilic proteins composed of 864 and 566 amino acid residues and with the relative molecular mass of 97.9 kDa and 64.6 kDa and the theoretical isoelectric points of 5.61 and 6.12, respectively. Sequence comparison and phylogenetic tree showed that SchCPS contained LHS, PNV, and DxDD motifs conserved in the CPS family and was categorized in the TPS-c subfamily, while SchKS contained DDxxD, NSE/DTE and PIx motifs conserved in the KS family and was categorized in the TPS-e subfamily. Functional validation showed that SchCPS catalyzed the protonation and cyclization of GGPP to ent-CPP, while SchKS acted on ent-CPP dephosphorylation and re-cyclization to ent-kaurene. In this study, the full-length sequences of SchCPS and SchKS were cloned and functionally verified for the first time, which not only enriched the existing CPS and KS gene libraries but also laid a foundation for the cloning and biosynthesis pathway analysis of more genes involved in the synthesis of active components in S. chamaejasme.
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Alquil e Aril Transferases , Filogenia , Proteínas de Plantas , Thymelaeaceae , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Alquil e Aril Transferases/química , Thymelaeaceae/genética , Thymelaeaceae/enzimologia , Thymelaeaceae/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Sequência de Aminoácidos , Diterpenos do Tipo Caurano/metabolismo , Diterpenos do Tipo Caurano/química , Alinhamento de Sequência , Clonagem MolecularRESUMO
PURPOSE: We conducted this study to evaluate the efficacy of total hysterectomy versus radical hysterectomy in the treatment of neuroendocrine cervical cancer (NECC). METHODS: Eligible NECC patients were identified from the Surveillance, Epidemiology and End Results (SEER) database. Demographic characteristics, clinical treatment and survival of the patients were collected. The overall survival (OS) and cancer-specific survival (CSS) were estimated by Kaplan-Meier analysis with log-rank test. RESULTS: A total of 286 patients were included, with 104 patients undergoing total hysterectomy and 182 patients undergoing radical hysterectomy. The 5-year OS were 50.8% in the total hysterectomy group and 47.5% in the radical hysterectomy group (p = 0.450); and the corresponding 5-year CSS were 51.6% and 49.1% (p = 0.494), respectively. Along with surgery, radiotherapy was given to 49.0% of patients in the total hysterectomy group and 50.5% in the radical hysterectomy group; and chemotherapy was administered to 77.9% of patients in the total hysterectomy group and 85.7% in the radical hysterectomy group. Unexpectedly, in patients who received adjuvant radiotherapy with or without chemotherapy, the OS was superior in the total hysterectomy group compared with the radical hysterectomy group (p = 0.034). While in patients who received chemotherapy alone and those who received neither radiotherapy nor chemotherapy, the OS still remained comparable between the total hysterectomy and radical hysterectomy group. CONCLUSION: Compared with radical hysterectomy, total hysterectomy was not associated with compromised survival prognosis in patients with NECC. Total hysterectomy has the potential to be a surgical alternative in the multimodal management of NECC.
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Histerectomia , Programa de SEER , Neoplasias do Colo do Útero , Humanos , Feminino , Histerectomia/métodos , Neoplasias do Colo do Útero/cirurgia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/mortalidade , Pessoa de Meia-Idade , Adulto , Carcinoma Neuroendócrino/cirurgia , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/mortalidade , IdosoRESUMO
OBJECTIVES: Ovarian cancer (OC) can occur at different ages and is affected by a variety of factors. In order to evaluate the risk of cardiovascular mortality in patients with ovarian cancer, we included influencing factors including age, histological type, surgical method, chemotherapy, whether distant metastasis, race and developed a nomogram to evaluate the ability to predict occurrence. At present, we have not found any correlation studies on cardiovascular death events in patients with ovarian cancer. This study was designed to provide targeted measures for effective prevention of cardiovascular death in patients with ovarian cancer. METHODS: Kaplan-Meier analysis and multivariable Cox proportional model were performed to evaluate the effectiveness of cardiovascular diseases on overall survival (OS) and ovarian cancer-specific survival (OCSS). We compared multiple groups including clinical, demographic, therapeutic characteristics and histological types. Cox risk regression analysis, Kaplan-Meier survival curves, and propensity score matching were employed for analyzing the data. RESULTS: A total of 88,653 ovarian cancer patients were collected, of which 2,282 (2.57%) patients died due to cardiovascular-related diseases. Age, chemotherapy and whether satisfactory cytoreduction surgery is still the most important factors affecting the prognosis of ovarian cancer patients, while different histological types, diagnosis time, and race also have a certain impact on the prognosis. The newly developed nomogram model showed excellent predictive performance, with a C-index of 0.759 (95%CI: 0.757-0.761) for the group. Elderly patients with ovarian cancer are still a high-risk group for cardiovascular death [HR: 21.07 (95%CI: 5.21-85.30), p < 0.001]. The calibration curve showed good agreement from predicted survival probabilities to actual observations. CONCLUSION: This study found that age, histology, surgery, race, chemotherapy, and tumor metastasis are independent prognostic factors for cardiovascular death in patients with ovarian cancer. The nomogram-based model can accurately predict the OS of ovarian cancer patients. It is expected to inform clinical decision-making and help develop targeted treatment strategies for this population.
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Doenças Cardiovasculares , Neoplasias Ovarianas , Humanos , Feminino , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/patologia , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/complicações , Pessoa de Meia-Idade , Idoso , Nomogramas , Adulto , Prognóstico , Fatores de Risco , Estimativa de Kaplan-Meier , Modelos de Riscos Proporcionais , Idoso de 80 Anos ou maisRESUMO
AIMS: We conducted a Mendelian randomization (MR) study to elucidate the anti-infective effects of ticagrelor. METHODS AND RESULTS: Single-nucleotide polymorphisms (SNPs) associated with serum levels of ticagrelor or its major metabolite AR-C124910XX (ARC) in the PLATelet inhibition and patient Outcomes trial were selected as genetic proxies for ticagrelor exposure. Positive control analyses indicated that genetically surrogated serum ticagrelor levels (six SNPs) but not ARC levels (two SNPs) were significantly associated with lower risks of coronary heart disease. Therefore, the six SNPs were used as genetic instruments for ticagrelor exposure, and the genome-wide association study data for five infection outcomes were derived from the UK Biobank and FinnGen consortium. The two-sample MR analyses based on inverse variance-weighted methods indicated that genetic liability to ticagrelor exposure could reduce the risk of bacterial pneumonia (odds ratio [OR]: 0.82, 95% confidence interval [CI]: 0.71-0.95, P = 8.75E-03) and sepsis (OR: 0.83, 95% CI: 0.73-0.94, P = 3.69E-03); however, no causal relationship between ticagrelor exposure and upper respiratory infection, pneumonia, and urinary tract infection was detected. Extensive sensitivity analyses corroborated these findings. CONCLUSION: Our MR study provides further evidence for the preventive effects of ticagrelor on bacterial pneumonia and sepsis.
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Solar fuels offer a promising approach to provide sustainable fuels by harnessing sunlight1,2. Following a decade of advancement, Cu2O photocathodes are capable of delivering a performance comparable to that of photoelectrodes with established photovoltaic materials3-5. However, considerable bulk charge carrier recombination that is poorly understood still limits further advances in performance6. Here we demonstrate performance of Cu2O photocathodes beyond the state-of-the-art by exploiting a new conceptual understanding of carrier recombination and transport in single-crystal Cu2O thin films. Using ambient liquid-phase epitaxy, we present a new method to grow single-crystal Cu2O samples with three crystal orientations. Broadband femtosecond transient reflection spectroscopy measurements were used to quantify anisotropic optoelectronic properties, through which the carrier mobility along the [111] direction was found to be an order of magnitude higher than those along other orientations. Driven by these findings, we developed a polycrystalline Cu2O photocathode with an extraordinarily pure (111) orientation and (111) terminating facets using a simple and low-cost method, which delivers 7 mA cm-2 current density (more than 70% improvement compared to that of state-of-the-art electrodeposited devices) at 0.5 V versus a reversible hydrogen electrode under air mass 1.5 G illumination, and stable operation over at least 120 h.
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With the rise of short-form video platforms and the increasing availability of data, we see the potential for people to share short-form videos embedded with data in situ (e.g., daily steps when running) to increase the credibility and expressiveness of their stories. However, creating and sharing such videos in situ is challenging since it involves multiple steps and skills (e.g., data visualization creation and video editing), especially for amateurs. By conducting a formative study (N=10) using three design probes, we collected the motivations and design requirements. We then built VisTellAR, a mobile AR authoring tool, to help amateur video creators embed data visualizations in short-form videos in situ. A two-day user study shows that participants (N=12) successfully created various videos with data visualizations in situ and they confirmed the ease of use and learning. AR pre-stage authoring was useful to assist people in setting up data visualizations in reality with more designs in camera movements and interaction with gestures and physical objects to storytelling.
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The tumor microenvironment (TME) is restricted in metabolic nutrients including the semi-essential amino acid arginine. While complete arginine deprivation causes T cell dysfunction, it remains unclear how arginine levels fluctuate in the TME to shape T cell fates. Here, we find that the 20-µM low arginine condition, representing the levels found in the plasma of patients with cancers, confers Treg-like immunosuppressive capacities upon activated T cells. In vivo mouse tumor models and human single-cell RNA-sequencing datasets reveal positive correlations between low arginine condition and intratumoral Treg accumulation. Mechanistically, low arginine-activated T cells engage in metabolic and transcriptional reprogramming, using the ATF4-SLC7A11-GSH axis, to preserve their suppressive function. These findings improve our understanding of the role of arginine in human T cell biology with potential applications for immunotherapy strategies.
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Fator 4 Ativador da Transcrição , Arginina , Linfócitos T CD4-Positivos , Arginina/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Animais , Humanos , Camundongos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Ativação Linfocitária/imunologia , Camundongos Endogâmicos C57BL , Sistema y+ de Transporte de Aminoácidos/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , Microambiente Tumoral/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Feminino , Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Sistemas de Transporte de Aminoácidos Básicos/genéticaRESUMO
Biodegradation of soil organic matter (SOM), which involves greenhouse gas (GHG) emissions, plays an essential role in the global carbon cycle. Over the past few decades, this has become an important research focus, particularly in natural ecosystems. SOM biodegradation significantly affects contaminants in the environment, such as mercury (Hg) methylation, producing highly toxic methylmercury (MeHg). However, the potential link between GHG production from SOM turnover in contaminated soils and biogeochemical processes involving contaminants remains unclear. In this study, we investigated the dynamics of GHG, MeHg production, and the relationship between biogeochemical processes in soils from two typical Hg mining sites. The two contaminated soils have different pathways, explaining the significant variations in GHG and MeHg production. The divergence of the microbial communities in these two biogeochemical processes is essential. In addition to the microbial role, abiotic factors such as Hg species can significantly affect MeHg production. On the other hand, we found an inverse relationship between CH4 and MeHg, suggesting that carbon emission reduction policies and management could inadvertently increase the MeHg levels. This highlights the need for an eclectic approach to organic carbon sequestration and contaminant containment. These findings suggest that it is difficult to establish a general pattern to describe and explain the SOM degradation and MeHg production in contaminated soils within the specific scenarios. However, this study provides a case study and helpful insights for further understanding the links between environmental risks and carbon turnover in Hg mining areas.
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Mercúrio , Compostos de Metilmercúrio , Oryza , Poluentes do Solo , Solo , Ecossistema , Poluentes do Solo/análise , Mercúrio/análise , Carbono , Biodegradação Ambiental , Monitoramento AmbientalRESUMO
Bone cancer is common and severe. Both primary (e.g., osteosarcoma, Ewing sarcoma) and secondary (e.g., metastatic) bone cancers lead to significant health problems and death. Currently, treatments such as chemotherapy, hormone therapy, and radiation therapy are used to treat bone cancer, but they often only shrink or slow tumor growth and do not eliminate cancer completely. The bone microenvironment contributes unique signals that influence cancer growth, immunogenicity, and metastasis. Traditional cancer therapies have limited effectiveness due to off-target effects and poor distribution on bones. As a result, therapies with improved specificity and efficacy for treating bone tumors are highly needed. One of the most promising strategies involves the targeted delivery of pharmaceutical agents to the site of bone cancer by introduction of bone-targeting moieties, such as bisphosphonates or oligopeptides. These moieties have high affinities to the bone hydroxyapatite matrix, a structure found exclusively in skeletal tissue, and can enhance the targeting ability and efficacy of anticancer drugs when combating bone tumors. This review focuses on the engineering of small molecules and proteins with bone-targeting moieties for the treatment of bone tumors.
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Antineoplásicos , Neoplasias Ósseas , Humanos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/terapia , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Animais , Difosfonatos/uso terapêutico , Difosfonatos/farmacologia , Difosfonatos/química , Sistemas de Liberação de Medicamentos/métodos , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Sarcoma de Ewing/tratamento farmacológico , Sarcoma de Ewing/terapia , Terapia de Alvo Molecular/métodos , Microambiente Tumoral/efeitos dos fármacosRESUMO
Digitoxin, an important secondary metabolite of Digitalis purpurea, is a commonly used cardiotonic in clinical practice. 3ß-Hydroxysteroid dehydrogenase(3ßHSD) is a key enzyme involved in the biosynthesis of digitoxin. It belongs to the short-chain dehydrogenase/reductase(SDR) family, playing a role in the biosynthesis of cardiac glycosides by oxidizing and isomerizing the precursor sterol. In this study, two 3ßHSD genes were cloned from D. purpurea. The results showed that the open reading frame(ORF) of Dp3ßHSD1 was 780 bp, encoding 259 amino acid residues. The ORF of Dp3ßHSD2 was 774 bp and encoded 257 residues. Dp3ßHSD1/2 had the cofactor binding site TGxxxA/GxG and the catalytic site YxxxK. In vitro experiments confirmed that Dp3ßHSD1/2 catalyzed the generation of progesterone from pregnenolone, and Dp3ßHSD1 had stronger catalytic capacity than Dp3ßHSD2. The expression level of Dp3ßHSD1 was much higher than that of Dp3ßHSD2 in leaves, and digitoxin was only accumulated in leaves. The results implied that Dp3ßHSD1 played a role in the dehydrogenation of pregnenolone to produce progesterone in the biosynthesis of digitoxin. This study provides a reference for further exploring the biosynthetic pathway of cardiac glycosides in D. purpurea.
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Digitoxina , Progesterona , Clonagem Molecular , Pregnenolona/metabolismo , Hidroxiesteroide DesidrogenasesRESUMO
Infantile hemangioma (IH) is the most common benign vascular tumor characterized by three phases - proliferation, early involution and late involution. Mast cells (MCs) play an important role in allergic reactions and numerous diseases, including tumors. While the mechanisms underlying MCs migration, activation and function in the life cycle of IH remain unclear, previous studies suggested that MCs circulate through the vasculature and migrate into IH, and subsequently mature and get activated. Estradiol (E2) emerges as a potential attractant for MC migration into IH and their subsequent activation. In various stages of IH, activated MCs secrete both proangiogenic and anti-angiogenic modulators, absorbed by various cells adjacent to them. Imbalances in these modulators may contribute to IH proliferation and involution.