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Antigen-specific memory CD4+ T cells can persist and confer rapid and efficient protection from microbial reinfection. However, the mechanisms underlying the long-term maintenance of the memory CD4+ T cell pool remain largely unknown. Here, using a mouse model of acute infection with lymphocytic choriomeningitis virus (LCMV), we found that the serine/threonine kinase complex mammalian target of rapamycin complex 2 (mTORC2) is critical for the long-term persistence of virus-specific memory CD4+ T cells. The perturbation of mTORC2 signaling at memory phase led to an enormous loss of virus-specific memory CD4+ T cells by a unique form of regulated cell death (RCD), ferroptosis. Mechanistically, mTORC2 inactivation resulted in the impaired phosphorylation of downstream AKT and GSK3ß kinases, which induced aberrant mitochondrial reactive oxygen species (ROS) accumulation and ensuing ferroptosis-causative lipid peroxidation in virus-specific memory CD4+ T cells; furthermore, the disruption of this signaling cascade also inhibited glutathione peroxidase 4 (GPX4), a major scavenger of lipid peroxidation. Thus, the mTORC2-AKT-GSK3ß axis functions as a key signaling hub to promote the longevity of virus-specific memory CD4+ T cells by preventing ferroptosis.
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Linfócitos T CD4-Positivos/imunologia , Ferroptose/imunologia , Memória Imunológica/imunologia , Longevidade/imunologia , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Alvo Mecanístico do Complexo 2 de Rapamicina/imunologia , Animais , Glicogênio Sintase Quinase 3 beta/imunologia , Peroxidação de Lipídeos/imunologia , Ativação Linfocitária/imunologia , Contagem de Linfócitos/métodos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-akt/imunologiaRESUMO
The differential performance of polygenic risk scores (PRSs) by group is one of the major ethical barriers to their clinical use. It is also one of the main practical challenges for any implementation effort. The social repercussions of how people are grouped in PRS research must be considered in communications with research participants, including return of results. Here, we outline the decisions faced and choices made by a large multi-site clinical implementation study returning PRSs to diverse participants in handling this issue of differential performance. Our approach to managing the complexities associated with the differential performance of PRSs serves as a case study that can help future implementers of PRSs to plot an anticipatory course in response to this issue.
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Predisposição Genética para Doença , Herança Multifatorial , Humanos , Herança Multifatorial/genética , Fatores de Risco , Estudo de Associação Genômica Ampla , Medição de Risco , Testes Genéticos/métodos , Estratificação de Risco GenéticoRESUMO
BACKGROUND AND AIMS: Patients with aggressive HCC have limited therapeutic options. Therefore, a better understanding of HCC pathogenesis is needed to improve treatment. Genomic studies of HCC have improved our understanding of cancer biology. However, the ubiquitomic characteristics of HCC remain poorly understood. We aimed to reveal the ubiquitomic characteristics of HCC and provide clinical feature biomarkers of the aggressive HCC that may be used for diagnosis or therapy in the clinic. APPROACH AND RESULTS: The comprehensive proteomic, phosphoproteomic, and ubiquitomic analyses were performed on tumors and adjacent normal liver tissues from 85 patients with HCC. HCCs displayed overexpression of drugable targets CBR1-S151 and CPNE1-S55. COL4A1, LAMC1, and LAMA4 were highly expressed in the disease free survival-poor patients. Phosphoproteomic and ubiquitomic features of HCC revealed cross talk in metabolism and metastasis. Ubiquitomics predicted diverse prognosis and clarified HCC subtype-specific proteomic signatures. Expression of biomarkers TUBA1A, BHMT2, BHMT, and ACY1 exhibited differential ubiquitination levels and displayed high prognostic risk scores, suggesting that targeting these proteins or their modified forms may be beneficial for future clinical treatment. We validated that TUBA1A K370 deubiquitination drove severe HCC and labeled an aggressive subtype of HCCs. TUBA1A K370 deubiquitination was at least partly attributed to protein kinase B-mediated USP14 activation in HCC. Notably, targeting AKT-USP14-TUBA1A complex promoted TUBA1A degradation and blocked liver tumorigenesis in vivo. CONCLUSIONS: This study expands our knowledge of ubiquitomic signatures, biomarkers, and potential therapeutic targets in HCC.
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Coronary plaque rupture remains the prominent mechanism of myocardial infarction. Accurate identification of rupture-prone plaque may improve clinical management. This study assessed the discriminatory performance of electrochemical impedance spectroscopy (EIS) in human cardiac explants to detect high-risk atherosclerotic features that portend rupture risk. In this single-center, prospective study, n = 26 cardiac explants were collected for EIS interrogation of the three major coronary arteries. Vessels in which advancement of the EIS catheter without iatrogenic plaque disruption was rendered impossible were not assessed. N = 61 vessels underwent EIS measurement and histological analyses. Plaques were dichotomized according to previously established high rupture-risk parameter thresholds. Diagnostic performance was determined via receiver operating characteristic areas-under-the-curve (AUC). Necrotic cores were identified in n = 19 vessels (median area 1.53 mm2) with a median fibrous cap thickness of 62 µm. Impedance was significantly greater in plaques with necrotic core area ≥1.75 mm2 versus <1.75 mm2 (19.8 ± 4.4 kΩ vs. 7.2 ± 1.0 kΩ, p = .019), fibrous cap thickness ≤65 µm versus >65 µm (19.1 ± 3.5 kΩ vs. 6.5 ± 0.9 kΩ, p = .004), and ≥20 macrophages per 0.3 mm-diameter high-power field (HPF) versus <20 macrophages per HPF (19.8 ± 4.1 kΩ vs. 10.2 ± 0.9 kΩ, p = .002). Impedance identified necrotic core area ≥1.75 mm2, fibrous cap thickness ≤65 µm, and ≥20 macrophages per HPF with AUCs of 0.889 (95% CI: 0.716-1.000) (p = .013), 0.852 (0.646-1.000) (p = .025), and 0.835 (0.577-1.000) (p = .028), respectively. Further, phase delay discriminated severe stenosis (≥70%) with an AUC of 0.767 (0.573-0.962) (p = .035). EIS discriminates high-risk atherosclerotic features that portend plaque rupture in human coronary artery disease and may serve as a complementary modality for angiography-guided atherosclerosis evaluation.
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Doença da Artéria Coronariana , Vasos Coronários , Espectroscopia Dielétrica , Placa Aterosclerótica , Humanos , Doença da Artéria Coronariana/patologia , Espectroscopia Dielétrica/métodos , Masculino , Feminino , Placa Aterosclerótica/patologia , Placa Aterosclerótica/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Prospectivos , Idoso , Vasos Coronários/patologia , Aterosclerose/patologia , Fatores de RiscoRESUMO
Distinguishing quiescent from rupture-prone atherosclerotic lesions has significant translational and clinical implications. Electrochemical impedance spectroscopy (EIS) characterizes biological tissues by assessing impedance and phase delay responses to alternating current at multiple frequencies. We evaluated invasive 6-point stretchable EIS sensors over a spectrum of experimental atherosclerosis and compared results with intravascular ultrasound (IVUS), molecular positron emission tomography (PET) imaging, and histology. Male New Zealand White rabbits (n = 16) were placed on a high-fat diet, with or without endothelial denudation via balloon injury of the infrarenal abdominal aorta. Rabbits underwent in vivo micro-PET imaging of the abdominal aorta with 68Ga-DOTATATE, 18F-NaF, and 18F-FDG, followed by invasive interrogation via IVUS and EIS. Background signal-corrected values of impedance and phase delay were determined. Abdominal aortic samples were collected for histology. Analyses were performed blindly. EIS impedance was associated with markers of plaque activity including macrophage infiltration (r = .813, p = .008) and macrophage/smooth muscle cell (SMC) ratio (r = .813, p = .026). Moreover, EIS phase delay correlated with anatomic markers of plaque burden, namely intima/media ratio (r = .883, p = .004) and %stenosis (r = .901, p = .002), similar to IVUS. 68Ga-DOTATATE correlated with intimal macrophage infiltration (r = .861, p = .003) and macrophage/SMC ratio (r = .831, p = .021), 18F-NaF with SMC infiltration (r = -.842, p = .018), and 18F-FDG correlated with macrophage/SMC ratio (r = .787, p = .036). EIS with phase delay integrates key atherosclerosis features that otherwise require multiple complementary invasive and non-invasive imaging approaches to capture. These findings indicate the potential of invasive EIS to comprehensively evaluate human coronary artery disease.
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Aterosclerose , Espectroscopia Dielétrica , Animais , Coelhos , Espectroscopia Dielétrica/métodos , Masculino , Aterosclerose/patologia , Aterosclerose/diagnóstico por imagem , Aorta Abdominal/patologia , Aorta Abdominal/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/patologia , Tomografia por Emissão de Pósitrons/métodos , Fenótipo , Modelos Animais de Doenças , Macrófagos/patologia , Macrófagos/metabolismoRESUMO
Idiopathic pulmonary fibrosis (IPF) poses significant challenges due to limited treatment options despite its complex pathogenesis involving cellular and molecular mechanisms. This study investigated the role of transient receptor potential ankyrin 1 (TRPA1) channels in regulating M2 macrophage polarization in IPF progression, potentially offering novel therapeutic targets. Using a bleomycin-induced pulmonary fibrosis model in C57BL/6J mice, we assessed the therapeutic potential of the TRPA1 inhibitor HC-030031. TRPA1 upregulation was observed in fibrotic lungs, correlating with worsened lung function and reduced survival. TRPA1 inhibition mitigated fibrosis severity, evidenced by decreased collagen deposition and restored lung tissue stiffness. Furthermore, TRPA1 blockade reversed aberrant M2 macrophage polarization induced by bleomycin, associated with reduced Smad2 phosphorylation in the TGF-ß1-Smad2 pathway. In vitro studies with THP-1 cells treated with bleomycin and HC-030031 corroborated these findings, highlighting TRPA1's involvement in fibrotic modulation and macrophage polarization control. Overall, targeting TRPA1 channels presents promising therapeutic potential in managing pulmonary fibrosis by reducing pro-fibrotic marker expression, inhibiting M2 macrophage polarization, and diminishing collagen deposition. This study sheds light on a novel avenue for therapeutic intervention in IPF, addressing a critical need in the management of this challenging disease.
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Fibrose Pulmonar Idiopática , Macrófagos , Canal de Cátion TRPA1 , Animais , Camundongos , Acetanilidas , Bleomicina , Colágeno , Proteínas do Citoesqueleto , Camundongos Endogâmicos C57BL , Purinas , Canal de Cátion TRPA1/metabolismoRESUMO
[This corrects the article DOI: 10.1371/journal.pgen.1009233.].
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To understand the role of myo-inositol oxygenase (miox) in the osmotic regulation of Nile tilapia, its expression was analyzed in various tissues. The results showed that the expression of miox gene was highest in the kidney, followed by the liver, and was significantly upregulated in the kidney and liver under 1 h hyperosmotic stress. The relative luminescence efficiency of the miox gene transcription starting site (-4,617 to +312 bp) under hyperosmotic stress was measured. Two fragments (-1,640/-1,619 and -620/-599) could induce the luminescence activity. Moreover, the -1,640/-1,619 and -620/-599 responded to hyperosmotic stress and high-glucose stimulation by base mutation, suggesting that osmotic and carbohydrate response elements may exist in this region. Finally, the salinity tolerance of Nile tilapia was significantly reduced after the knocking down of miox gene. The accumulation of myo-inositol was affected, and the expression of enzymes in glucose metabolism was significantly reduced after the miox gene was knocked down. Furthermore, hyperosmotic stress can cause oxidative stress, and MIOX may help maintain the cell redox balance under hyperosmotic stress. In summary, MIOX is essential in osmotic regulation to enhance the salinity tolerance of Nile tilapia by affecting myo-inositol accumulation, glucose metabolism, and antioxidant performance.NEW & NOTEWORTHY Myo-inositol oxygenase (MIOX) is the rate-limiting enzyme that catalyzes the first step of MI metabolism and determines MI content in aquatic animals. To understand the role of miox in the osmotic regulation of Nile tilapia, we analyzed its expression in different tissues and its function under hyperosmotic stress. This study showed that miox is essential in osmotic regulation to enhance the salinity tolerance of Nile tilapia by affecting myo-inositol accumulation, glucose metabolism, and antioxidant performance.
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Ciclídeos , Animais , Ciclídeos/genética , Ciclídeos/metabolismo , Inositol Oxigenase/genética , Inositol Oxigenase/metabolismo , Antioxidantes , Inositol/metabolismo , Glucose/metabolismoRESUMO
The mitochondrial citrate shuttle, which relies on the solute carrier family 25 member 1 (SLC25A1), plays a pivotal role in transporting citrate from the mitochondria to the cytoplasm. This shuttle supports glycolysis, lipid biosynthesis, and protein acetylation. Previous research has primarily focused on SLC25A1 in pathological models, particularly high-fat diet (HFD)-induced obesity. However, the impact of SLC25A1 inhibition on nutrient metabolism under HFD remains unclear. To address this gap, we used zebrafish (Danio rerio) and Nile tilapia (Oreochromis niloticus) to evaluate the effects of inhibiting Slc25a1. In zebrafish, we administered Slc25a1-specific inhibitors (CTPI-2) for 4 wk, whereas Nile tilapia received intraperitoneal injections of dsRNA to knock down slc25a1b for 7 days. Inhibition of the mitochondrial citrate shuttle effectively protected zebrafish from HFD-induced obesity, hepatic steatosis, and insulin resistance. Of note, glucose tolerance was unaffected. Inhibition of Slc25a1 altered hepatic protein acetylation patterns, with decreased cytoplasmic acetylation and increased mitochondrial acetylation. Under HFD conditions, Slc25a1 inhibition promoted fatty acid oxidation and reduced hepatic triglyceride (TAG) accumulation by deacetylating carnitine palmitoyltransferase 1a (Cpt1a). In addition, Slc25a1 inhibition triggered acetylation-induced inactivation of Pdhe1α, leading to a reduction in glucose oxidative catabolism. This was accompanied by enhanced glucose uptake and storage in zebrafish livers. Furthermore, Slc25a1 inhibition under HFD conditions activated the SIRT1/PGC1α pathway, promoting mitochondrial proliferation and enhancing oxidative phosphorylation for energy production. Our findings provide new insights into the role of nonhistone protein acetylation via the mitochondrial citrate shuttle in the development of hepatic lipid deposition and hyperglycemia caused by HFD.NEW & NOTEWORTHY The mitochondrial citrate shuttle is a crucial physiological process for maintaining metabolic homeostasis. In the present study, we found that inhibition of mitochondrial citrate shuttle (Slc25a1) could alleviate metabolic syndromes induced by high-fat diet (HFD) through remodeling hepatic protein acetylation modification. Briefly, Slc25a1 inhibition reduces hepatic triglyceride deposition by deacetylating Cpt1a and reduces glucose oxidative catabolism by acetylating Pdhe1α. Our study provides new insights into the treatment of diet-induced metabolic syndromes.
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Ácido Cítrico , Dieta Hiperlipídica , Peixe-Zebra , Animais , Dieta Hiperlipídica/efeitos adversos , Ácido Cítrico/metabolismo , Síndrome Metabólica/metabolismo , Síndrome Metabólica/prevenção & controle , Síndrome Metabólica/genética , Síndrome Metabólica/etiologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Carnitina O-Palmitoiltransferase/metabolismo , Carnitina O-Palmitoiltransferase/genética , Obesidade/metabolismo , Obesidade/prevenção & controle , Obesidade/genética , Obesidade/etiologia , Acetilação , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Fígado/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Resistência à Insulina , Fígado Gorduroso/metabolismo , Fígado Gorduroso/prevenção & controle , Fígado Gorduroso/patologia , Fígado Gorduroso/etiologia , Metabolismo dos Lipídeos/efeitos dos fármacosRESUMO
Pharmacological inhibition of mitochondrial fatty acid oxidation (FAO) has been clinically used to alleviate certain metabolic diseases by remodeling cellular metabolism. However, mitochondrial FAO inhibition also leads to mechanistic target of rapamycin complex 1 (mTORC1) activation-related protein synthesis and tissue hypertrophy, but the mechanism remains unclear. Here, by using a mitochondrial FAO inhibitor (mildronate or etomoxir) or knocking out carnitine palmitoyltransferase-1, we revealed that mitochondrial FAO inhibition activated the mTORC1 pathway through general control nondepressible 5-dependent Raptor acetylation. Mitochondrial FAO inhibition significantly promoted glucose catabolism and increased intracellular acetyl-CoA levels. In response to the increased intracellular acetyl-CoA, acetyltransferase general control nondepressible 5 activated mTORC1 by catalyzing Raptor acetylation through direct interaction. Further investigation also screened Raptor deacetylase histone deacetylase class II and identified histone deacetylase 7 as a potential regulator of Raptor. These results provide a possible mechanistic explanation for the mTORC1 activation after mitochondrial FAO inhibition and also bring light to reveal the roles of nutrient metabolic remodeling in regulating protein acetylation by affecting acetyl-CoA production.
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BACKGROUND & AIMS: Endoplasmic reticulum (ER) stress of hepatocytes plays a causative role in non-alcoholic fatty liver disease (NAFLD). Reduced expression of hepatic nuclear factor 4α (HNF4α) is a critical event in the pathogenesis of NAFLD and other liver diseases. Whether ER stress regulates HNF4α expression remains unknown. The aim of this study was to delineate the machinery of HNF4α protein degradation and explore a therapeutic strategy based on protecting HNF4α stability during NAFLD progression. METHODS: Correlation of HNF4α and tribbles homologue 3 (TRIB3), an ER stress sensor, was evaluated in human and mouse NAFLD tissues. RNA-sequencing, mass spectrometry analysis, co-immunoprecipitation, in vivo and in vitro ubiquitination assays were used to elucidate the mechanisms of TRIB3-mediated HNF4α degradation. Molecular docking and co-immunoprecipitation analyses were performed to identify a cell-penetrating peptide that ablates the TRIB3-HNF4α interaction. RESULTS: TRIB3 directly interacts with HNF4α and mediates ER stress-induced HNF4α degradation. TRIB3 recruits tripartite motif containing 8 (TRIM8) to form an E3 ligase complex that catalyzes K48-linked polyubiquitination of HNF4α on lysine 470. Abrogating the degradation of HNF4α attenuated the effect of TRIB3 on a diet-induced NAFLD model. Moreover, the TRIB3 gain-of-function variant p.Q84R is associated with NAFLD progression in patients, and induces lower HNF4α levels and more severe hepatic steatosis in mice. Importantly, disrupting the TRIB3-HNF4α interaction using a cell-penetrating peptide restores HNF4α levels and ameliorates NAFLD progression in mice. CONCLUSIONS: Our findings unravel the machinery of HNF4α protein degradation and indicate that targeting TRIB3-TRIM8 E3 complex-mediated HNF4α polyubiquitination may be an ideal strategy for NAFLD therapy. IMPACT AND IMPLICATIONS: Reduced expression of hepatic nuclear factor 4α (HNF4α) is a critical event in the pathogenesis of NAFLD and other liver diseases. However, the mechanism of HNF4α protein degradation remains unknown. Herein, we reveal that TRIB3-TRIM8 E3 ligase complex is responsible for HNF4α degradation during NAFLD. Inhibiting the TRIB3-HNF4α interaction effectively stabilized HNF4α protein levels and transcription factor activity in the liver and ameliorated TRIB3-mediated NAFLD progression. Our findings demonstrate that disturbing the TRIM8-TRIB3-HNF4α interaction may provide a novel approach to treat NAFLD and even other liver diseases by stabilizing the HNF4α protein.
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Peptídeos Penetradores de Células , Hepatopatia Gordurosa não Alcoólica , Proteínas Serina-Treonina Quinases , Animais , Humanos , Camundongos , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/metabolismo , Peptídeos Penetradores de Células/metabolismo , Fígado/patologia , Simulação de Acoplamento Molecular , Proteínas do Tecido Nervoso , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Repressoras , Ubiquitina-Proteína Ligases/metabolismoRESUMO
In response to the critical challenges of interfacial impedance and volumetric changes in Li(1+x)AlxTi(2x)(PO4)3 (LATP)-based lithium metal batteries, an elastomeric lithium-conducting interlayer fabricates from fluorinated hydrogenated nitrile butadiene rubber (F-HNBR) matrix is introduced herein. Owing to the vulcanization, vapor-phase fluorination, and plasticization processes, the lithium-conducting interlayer exhibits a high elasticity of 423%, exceptional fatigue resistance (10 000 compression cycles), superior ionic conductivity of 6.3 × 10-4 S cm-1, and favorable lithiophilicity, rendering it an ideal buffer layer. By integrating the F-HNBR interlayer, the LATP-based lithium symmetric cells demonstrate an extended cycle life of up to 1600 h at 0.1 mA cm-2 and can also endure deep charge/discharge cycles (0.5 mAh cm-2) for the same duration. Furthermore, the corresponding lithium metal full cells achieve 500 cycles at 0.5 C with 98.3% capacity retention and enable a high-mass-loading cathode of 11.1 mg cm-2 to operate at room temperature.
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The receptor binding domain (RBD) of the SARS-CoV-2 Spike (S) glycoprotein is an appealing immunogen, but associated vaccine approaches must overcome the hapten-like nature of the compact protein and adapt to emerging variants with evolving RBD sequences. Here, a vaccine manufacturing methodology is proposed comprising a sterile-filtered freeze-dried lipid cake formulation that can be reconstituted with liquid proteins to instantaneously form liposome-displayed protein nanoparticles. Mannitol is used as a bulking agent and a small amount of Tween-80 surfactant is required to achieve reconstituted submicron particles that do not precipitate prior to usage. The lipid particles include an E. coli-derived monophosphoryl lipid A (EcML) for immunogenicity, and cobalt porphyrin-phospholipid (CoPoP) for antigen display. Reconstitution of the lipid cake with aqueous protein results in rapid conversion of the RBD into intact liposome-bound format prior to injection. Protein particles can readily be formed with sequent-divergent RBD proteins derived from the ancestral or Omicron strains. Immunization of mice elicits antibodies that neutralize respective viral strains. When K18-hACE2 transgenic mice are immunized and challenged with ancestral SARS-CoV-2 or the Omicron BA.5 variant, both liquid liposomes displaying the RBD and rapid reconstituted particles protect mice from infection, as measured by the viral load in the lungs and nasal turbinates.
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Vacinas contra COVID-19 , COVID-19 , Animais , Camundongos , Nanovacinas , SARS-CoV-2 , Escherichia coli , Lipossomos , COVID-19/prevenção & controle , LipídeosRESUMO
Clinical data are increasingly being mined to derive new medical knowledge with a goal of enabling greater diagnostic precision, better-personalized therapeutic regimens, improved clinical outcomes and more efficient utilization of health-care resources. However, clinical data are often only available at irregular intervals that vary between patients and type of data, with entries often being unmeasured or unknown. As a result, missing data often represent one of the major impediments to optimal knowledge derivation from clinical data. The Data Analytics Challenge on Missing data Imputation (DACMI) presented a shared clinical dataset with ground truth for evaluating and advancing the state of the art in imputing missing data for clinical time series. We extracted 13 commonly measured blood laboratory tests. To evaluate the imputation performance, we randomly removed one recorded result per laboratory test per patient admission and used them as the ground truth. DACMI is the first shared-task challenge on clinical time series imputation to our best knowledge. The challenge attracted 12 international teams spanning three continents across multiple industries and academia. The evaluation outcome suggests that competitive machine learning and statistical models (e.g. LightGBM, MICE and XGBoost) coupled with carefully engineered temporal and cross-sectional features can achieve strong imputation performance. However, care needs to be taken to prevent overblown model complexity. The challenge participating systems collectively experimented with a wide range of machine learning and probabilistic algorithms to combine temporal imputation and cross-sectional imputation, and their design principles will inform future efforts to better model clinical missing data.
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Algoritmos , Aprendizado de Máquina , Estudos Transversais , Coleta de Dados , Humanos , Modelos EstatísticosRESUMO
Brain damage caused by acute hypoxia is associated with the physiological activities of mitochondria. Although mitochondria being dynamically regulated, our comprehensive understanding of the response of specific brain cell types to acute hypoxia remains ambiguous. Tumor necrosis factor receptor-associated protein 1 (TRAP1), a mitochondrial-based molecular chaperone, plays a role in controlling mitochondrial movements. Herein, we demonstrated that acute hypoxia significantly alters mitochondria morphology and functionality in both in vivo and in vitro brain injury experiments. Summary-data-based Mendelian Randomization (SMR) analyses revealed possible causative links between mitochondria-related genes and hypoxia injury. Advancing the protein-protein interaction network and molecular docking further elucidated the associations between TRAP1 and mitochondrial dynamics. Furthermore, it was shown that TRAP1 knockdown levels variably affected the expression of key mitochondrial dynamics proteins (DRP1, FIS1, and MFN1/2) in primary hippocampal neurons, astrocytes, and BV-2 cell, leading to changes in mitochondrial structure and function. Understanding the function of TRAP1 in altering mitochondrial physiological activity during hypoxia-induced acute brain injury could help serve as a potential therapeutic target to mitigate neurological damage.
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Lesões Encefálicas , Proteínas de Choque Térmico HSP90 , Mitocôndrias , Dinâmica Mitocondrial , Animais , Mitocôndrias/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Neurônios/metabolismo , Neurônios/patologia , Humanos , Masculino , Mapas de Interação de Proteínas , Simulação de Acoplamento Molecular , Camundongos , Astrócitos/metabolismo , Astrócitos/patologia , Camundongos Endogâmicos C57BL , Hipóxia/complicações , Hipóxia/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Doença AgudaRESUMO
BACKGROUND: Stroke is a globally dangerous disease capable of causing irreversible neuronal damage with limited therapeutic options. Meldonium, an inhibitor of carnitine-dependent metabolism, is considered an anti-ischemic drug. However, the mechanisms through which meldonium improves ischemic injury and its potential to protect neurons remain largely unknown. METHODS: A rat model with middle cerebral artery occlusion (MCAO) was used to investigate meldonium's neuroprotective efficacy in vivo. Infarct volume, neurological deficit score, histopathology, neuronal apoptosis, motor function, morphological alteration and antioxidant capacity were explored via 2,3,5-Triphenyltetrazolium chloride staining, Longa scoring method, hematoxylin and eosin staining, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay, rotarod test, transmission electron microscopy and Oxidative stress index related kit. A primary rat hippocampal neuron model subjected to oxygen-glucose deprivation reperfusion was used to study meldonium's protective ability in vitro. Neuronal viability, mitochondrial membrane potential, mitochondrial morphology, respiratory function, ATP production, and its potential mechanism were assayed by MTT cell proliferation and cytotoxicity assay kit, cell-permeant MitoTracker® probes, mitochondrial stress, real-time ATP rate and western blotting. RESULTS: Meldonium markedly reduced the infarct size, improved neurological function and motor ability, and inhibited neuronal apoptosis in vivo. Meldonium enhanced the morphology, antioxidant capacity, and ATP production of mitochondria and inhibited the opening of the mitochondrial permeability transition pore in the cerebral cortex and hippocampus during cerebral ischemia-reperfusion injury (CIRI) in rats. Additionally, meldonium improved the damaged fusion process and respiratory function of neuronal mitochondria in vitro. Further investigation revealed that meldonium activated the Akt/GSK-3ß signaling pathway to inhibit mitochondria-dependent neuronal apoptosis. CONCLUSION: Our study demonstrated that meldonium shows a neuroprotective function during CIRI by preserving the mitochondrial function, thus prevented neurons from apoptosis.
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Apoptose , Sobrevivência Celular , Metilidrazinas , Mitocôndrias , Neurônios , Fármacos Neuroprotetores , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Animais , Fármacos Neuroprotetores/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/tratamento farmacológico , Masculino , Sobrevivência Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Metilidrazinas/farmacologia , Metilidrazinas/uso terapêutico , Isquemia Encefálica/patologia , Isquemia Encefálica/tratamento farmacológico , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , RatosRESUMO
The emerging evidence of human infections with emerging viruses suggests their potential public health importance. A novel taxon of viruses named Statoviruses (for stool-associated Tombus-like viruses) was recently identified in the gastrointestinal tracts of multiple mammals. Here we report the discovery of respiratory Statovirus-like viruses (provisionally named Restviruses) from the respiratory tracts of five patients experiencing acute respiratory disease with Human coronavirus OC43 infection through the retrospective analysis of meta-transcriptomic data. Restviruses shared 53.1%-98.8% identities of genomic sequences with each other and 39.9%-44.3% identities with Statoviruses. The phylogenetic analysis revealed that Restviruses together with a Stato-like virus from nasal-throat swabs of Vietnamese patients with acute respiratory disease, formed a well-supported clade distinct from the taxon of Statoviruses. However, the consistent genome characteristics of Restviruses and Statoviruses suggested that they might share similar evolutionary trajectories. These findings warrant further studies to elucidate the etiological and epidemiological significance of the emerging Restviruses.
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Genoma Viral , Filogenia , Infecções Respiratórias , Humanos , China/epidemiologia , Genoma Viral/genética , Infecções Respiratórias/virologia , Infecções Respiratórias/epidemiologia , Masculino , Feminino , Estudos Retrospectivos , Sistema Respiratório/virologia , Pré-Escolar , Adulto , Criança , RNA Viral/genética , Pessoa de Meia-IdadeRESUMO
Digital holographic microscopy (DHM) is a powerful quantitative phase imaging (QPI) technique that is capable of recording sample's phase information to enhance image contrast. In off-axis DHM, high-quality QPI images can be generated within a single recorded hologram, and the system stability can be enhanced by common-path configuration. Diffraction gratings are widely used components in common-path DHM systems; however, the presence of multiple diffraction beams leads to system power loss. Here, we propose and demonstrate implementation of a volume holographic grating (VHG) in common-path DHM, which provides single diffraction order. VHG in common-path DHM (i.e., VHG-DHM) helps in improving signal-to-noise ratio as compared to the conventional DHM. In addition, VHG, with inherently high angular selectivity, reduces image noise caused by stray light. With a simple fabrication process, it is convenient to utilize VHG to control the beam separation angle of DHM. Further, by using Bragg-matched wavelength degeneracy to avoid potential cell damaging effect in blue light, the VHG is designed for recording at a maximum sensitive wavelength of â¼488â nm, while our VHG-DHM is operated at the longer wavelength of red 632.8â nm for cell observation. Experimental results, measured by the VHG-DHM, show the measurement of target thickness ranging from 100â nm to 350â nm. In addition, stability of the system is quantitatively measured. High-contrast QPI images of human lung cancer cells are demonstrated.
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In this paper, we firstly propose a method to measure the topological charges (TCs) of a circular Bessel Gaussian beam with multiple vortex singularities (CBGBMVS) by utilizing cross phase. Based on theory and experiment, the cross phase is utilized to realize the TCs measurement of the CBGBMVS in free space with different situations, such as different singularity number, TCs and singularity location. Especially, the TCs measurement method is also investigated and verified in atmosphere turbulence. Our work provides an effective and convenient way to realize the TCs measurement of multiple singularities embedded in abruptly autofocusing host beams which has plenty of potential application in optical communication.
RESUMO
Airy light sheets combined with the deconvolution approach can provide multiple benefits, including large field of view (FOV), thin optical sectioning, and high axial resolution. The efficient design of an Airy light-sheet fluorescence microscope requires a compact illumination system. Here, we show that an Airy light sheet can be conveniently implemented in microscopy using a volume holographic grating (VHG). To verify the FOV and the axial resolution of the proposed VHG-based Airy light-sheet fluorescence microscope, ex-vivo fluorescently labeled Caenorhabditis elegans (C. elegans) embryos were imaged, and the Richardson-Lucy deconvolution method was used to improve the image contrast. Optimized parameters for deconvolution were compared with different methods. The experimental results show that the FOV and the axial resolution were 196 µm and 3 µm, respectively. The proposed method of using a compact VHG to replace the common spatial light modulator provides a direct solution to construct a compact light-sheet fluorescence microscope.