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mTORC1 and GSK3 play critical roles in early stages of (macro)autophagy, but how they regulate late steps of autophagy remains poorly understood. Here we show that mTORC1 and GSK3-TIP60 signaling converge to modulate autophagosome maturation through Pacer, an autophagy regulator that was identified in our recent study. Hepatocyte-specific Pacer knockout in mice results in impaired autophagy flux, glycogen and lipid accumulation, and liver fibrosis. Under nutrient-rich conditions, mTORC1 phosphorylates Pacer at serine157 to disrupt the association of Pacer with Stx17 and the HOPS complex and thus abolishes Pacer-mediated autophagosome maturation. Importantly, dephosphorylation of Pacer under nutrient-deprived conditions promotes TIP60-mediated Pacer acetylation, which facilitates HOPS complex recruitment and is required for autophagosome maturation and lipid droplet clearance. This work not only identifies Pacer as a regulator in hepatic autophagy and liver homeostasis in vivo but also reveals a signal integration mechanism involved in late stages of autophagy and lipid metabolism.
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Autofagossomos/enzimologia , Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Quinase 3 da Glicogênio Sintase/metabolismo , Metabolismo dos Lipídeos , Fígado/enzimologia , Lisina Acetiltransferase 5/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Transativadores/metabolismo , Acetilação , Animais , Autofagossomos/patologia , Proteínas Relacionadas à Autofagia/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Quinase 3 da Glicogênio Sintase/genética , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Gotículas Lipídicas/metabolismo , Fígado/patologia , Lisina Acetiltransferase 5/genética , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Proteínas de Membrana , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/enzimologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Ligação a Fosfato/genética , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Transdução de Sinais , Transativadores/genética , Proteínas Supressoras de TumorRESUMO
Polymers have been widely applied in various fields in the daily routines and the manufacturing. Despite the awareness of the aggressive and inevitable aging for the polymers, it still remains a challenge to choose an appropriate characterization strategy for evaluating the aging behaviors. The difficulties lie in the fact that the polymer features from the different aging stages require different characterization methods. In this review, we present an overview of the characterization strategies preferable for the initial, accelerated, and late stages during polymer aging. The optimum strategies have been discussed to characterize the generation of radicals, variation of functional groups, substantial chain scission, formation of low-molecular products, and deterioration in the polymers' macro-performances. In view of the advantages and the limitations of these characterization techniques, their utilization in a strategic approach is considered. In addition, we highlight the structure-property relationship for the aged polymers and provide available guidance for lifetime prediction. This review could allow the readers to be knowledgeable of the features for the polymers in the different aging stages and provide access to choose the optimum characterization techniques. We believe that this review will attract the communities dedicated to materials science and chemistry.
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Human papillomavirus (HPV) integration is a critical step in cervical cancer development; however, the oncogenic mechanism at the genome-wide transcriptional level is still poorly understood. In this study, we employed integrative analysis on multi-omics data of six HPV-positive and three HPV-negative cell lines. Through HPV integration detection, super-enhancer (SE) identification, SE-associated gene expression and extrachromosomal DNA (ecDNA) investigation, we aimed to explore the genome-wide transcriptional influence of HPV integration. We identified seven high-ranking cellular SEs generated by HPV integration in total (the HPV breakpoint-induced cellular SEs, BP-cSEs), leading to intra-chromosomal and inter-chromosomal regulation of chromosomal genes. The pathway analysis revealed that the dysregulated chromosomal genes were correlated to cancer-related pathways. Importantly, we demonstrated that BP-cSEs existed in the HPV-human hybrid ecDNAs, explaining the above transcriptional alterations. Our results suggest that HPV integration generates cellular SEs that function as ecDNA to regulate unconstrained transcription, expanding the tumorigenic mechanism of HPV integration and providing insights for developing new diagnostic and therapeutic strategies.
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DNA , Elementos Facilitadores Genéticos , Genoma Humano , Papillomavirus Humano , Infecções por Papillomavirus , Transcrição Gênica , Neoplasias do Colo do Útero , Integração Viral , Feminino , Humanos , Papillomavirus Humano/genética , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Integração Viral/genética , Elementos Facilitadores Genéticos/genética , DNA/genética , DNA/metabolismo , Genoma Humano/genética , Carcinogênese , Pontos de Quebra do Cromossomo , Cromossomos Humanos/genéticaRESUMO
Super-resolution imaging has rapidly emerged as an optical microscopy technique, offering advantages of high optical resolution over the past two decades; achieving improved imaging resolution requires significant efforts in developing super-resolution imaging agents characterized by high brightness, high contrast and high sensitivity to fluorescence switching. Apart from technical requirements in optical systems and algorithms, super-resolution imaging relies on fluorescent dyes with special photophysical or photochemical properties. The concept of aggregation-induced emission (AIE) was proposed in 2001, coinciding with unprecedented advancements and innovations in super-resolution imaging technology. AIE probes offer many advantages, including high brightness in the aggregated state, low background signal, a larger Stokes shift, ultra-high photostability, and excellent biocompatibility, making them highly promising for applications in super-resolution imaging. In this review, we summarize the progress in implementation methods and provide insights into the mechanism of AIE-based super-resolution imaging, including fluorescence switching resulting from photochemically-converted aggregation-induced emission, electrostatically controlled aggregation-induced emission and specific binding-regulated aggregation-induced emission. Particularly, the aggregation-induced emission principle has been proposed to achieve spontaneous fluorescence switching, expanding the selection and application scenarios of super-resolution imaging probes. By combining the aggregation-induced emission principle and specific molecular design, we offer some comprehensive insights to facilitate the applications of AIEgens (AIE-active molecules) in super-resolution imaging.
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Pyroptosis, a newly characterized type of inflammatory programmed cell death (PCD), is usually triggered by multiple inflammasomes which can recognize different danger or damage-associated molecular patterns (DAMPs), leading to the activation of caspase-1 and the cleavage of gasdermin D (GSDMD). Gasdermin family pore-forming proteins are the executers of pyroptosis and are normally maintained in an inactive state through auto-inhibition. Upon caspases mediated cleavage of gasdermins, the pro-pyroptotic N-terminal fragment is released from the auto-inhibition of C-terminal fragment and oligomerizes, forming pores in the plasma membrane. This results in the secretion of interleukin (IL)-1ß, IL-18, and high-mobility group box 1 (HMGB1), generating osmotic swelling and lysis. Current therapeutic approaches including chemotherapy, radiotherapy, molecularly targeted therapy and immunotherapy for lung cancer treatment efficiently force the cancer cells to undergo pyroptosis, which then generates local and systemic antitumor immunity. Thus, pyroptosis is recognized as a new therapeutic regimen for the treatment of lung cancer. In this review, we briefly describe the signaling pathways involved in pyroptosis, and endeavor to discuss the antitumor effects of pyroptosis and its potential application in lung cancer therapy, focusing on the contribution of pyroptosis to microenvironmental reprogramming and evocation of antitumor immune response.
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BACKGROUND: Symptomatic brainstem cavernous malformations (BSCMs) pose a high risk of morbidity and mortality due to recurrent hemorrhage, warranting aggressive management. However, few studies have compared the effectiveness of different treatment modalities for BSCMs. We aimed to assess the association of treatment modalities with recurrent hemorrhage and neurological outcomes in patients with BSCM. METHODS: We conducted a retrospective cohort study using an observational registry database covering population of southwest and southeast China. Adult patients with BSCM were included and followed up between March 1, 2011, to March 31, 2023. We compared outcomes between microsurgery and stereotactic radiosurgery (SRS) in propensity score-matched case pairs, incorporating demographic, medical history, and lesion characteristics. The outcomes studied included recurrent hemorrhage and poor prognosis (defined as a Glasgow Outcome Scale score, <4). Absolute rate differences and hazard ratios (HRs) with 95% CIs were calculated using Cox models. RESULTS: Among 736 diagnosed patients with BSCM, 96 (48 matched pairs) were included after exclusions and propensity score matching (mean age, 43.1 [SD, 12.1] years; 50% women). During the median 5-year follow-up, no significant differences in recurrent hemorrhage (4.2% [microsurgery] versus 14.6% [SRS], HR, 3.90 [95% CI, 0.46-32.65]; P=0.21) and poor prognosis (12.5% [microsurgery] versus 8.3% [SRS], HR, 0.29 [95% CI, 0.08-1.08]; P=0.07) were observed between microsurgery and SRS recipients. Furthermore, either microsurgery or SRS correlated with fewer recurrent hemorrhage (HR, 0.09 [95% CI, 0.02-0.39]; P=0.001; HR, 0.21 [95% CI, 0.07-0.69]; P=0.01) compared with conservative treatment. CONCLUSIONS: In this study, both microsurgery and SRS were safe and effective for BSCM, demonstrated comparable outcomes in recurrent hemorrhage and poor prognosis. However, interpretation should be cautious due to the potential for residual confounding. REGISTRATION: URL: https://www.chictr.org.cn/; Unique identifier: ChiCTR2300070907.
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BACKGROUND: Surgical risk assessment is intriguing for clinical decision-making of brainstem cavernous malformation (BSCM) treatment. While the BSCM grading scale, encompassing size, developmental venous anomaly, crossing axial midpoint, age, and timing of intervention, is increasingly utilized, the clinical relevance of neurological fluctuation and recurrent hemorrhage has not been incorporated. This study aimed to propose a supplementary grading scale with enhanced predictive efficacy. METHODS: Using a retrospective nationwide registry of consecutive patients with BSCMs undergoing surgery in China from March 2011 to May 2023, a new supplementary BSCM grading scale was developed from a derivative cohort of 260 patients and validated in an independent concurrent cohort of 67 patients. The primary outcome was unfavorable neurological function (modified Rankin Scale score >2) at the latest follow-up. The performance of the supplementary grading system was evaluated for discrimination, calibration, and clinical utility and further compared with its original counterpart. RESULTS: Over a follow-up of at least 6 months after surgery, the unfavorable outcomes were 31% in the overall cohort (101/327 patients). A preoperative motor deficit (odds ratio, 3.13; P=0.001), recurrent hemorrhage (odds ratio, 3.05; P<0.001), timing of intervention (odds ratio, 7.08; P<0.001), and crossing the axial midpoint (odds ratio, 2.57; P=0.006) were associated with the unfavorable outcomes and composed the initial Huashan grading variables. A supplementary BSCM grading system was subsequently developed by incorporating the Huashan grading variables into the original BSCM grading scale. The predictive capability of the supplementary scale was consistently superior to the original counterpart in either the derivative cohort (area under the receiver operating characteristic curve, 0.74 [95% CI, 0.68-0.80] for the supplementary versus 0.68 [95% CI, 0.61-0.74] for the original) or the validation cohort (0.75 [95% CI, 0.62-0.87] versus 0.64 [95% CI, 0.48-0.81]). CONCLUSIONS: This study highlights the neurological relevance of BSCM hemorrhage in surgical risk assessment. Via compositing preoperative motor function and recurrent hemorrhages, a supplementary grading scale may improve a dynamic risk assessment for clinical decisions in the management of BSCMs.
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Hemangioma Cavernoso do Sistema Nervoso Central , Humanos , Masculino , Feminino , Adulto , Hemangioma Cavernoso do Sistema Nervoso Central/cirurgia , Estudos Retrospectivos , Pessoa de Meia-Idade , Tronco Encefálico/cirurgia , Sistema de Registros , Resultado do Tratamento , Adolescente , Adulto Jovem , Medição de Risco , ChinaRESUMO
Pterostilbene is a phenolic compound commonly found in blueberries, peanuts, grapes, and other plants. It is a dimethoxy derivative of resveratrol. In recent years, it has gained significant attention due to its remarkable anti-inflammatory and antioxidant effects. In addition, its high bioavailability and low toxicity in many species has contributed to its promising research prospects. Cardiovascular disease is closely related to pathological processes such as inflammation and oxidative stress, which aligns well with the treatment applications of pterostilbene. As a result, numerous studies have investigated the effects of pterostilbene on cardiovascular health and disease. This paper summarizes the current research on pterostilbene, with a specific focus on its potential therapeutic role in treating cardiovascular disease.
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Degradation of endoplasmic reticulum (ER) by selective autophagy (ER-phagy) is crucial for ER homeostasis. However, it remains unclear how ER scission is regulated for subsequent autophagosomal sequestration and lysosomal degradation. Here, we show that oligomerization of ER-phagy receptor FAM134B (also referred to as reticulophagy regulator 1 or RETREG1) through its reticulon-homology domain is required for membrane fragmentation in vitro and ER-phagy in vivo. Under ER-stress conditions, activated CAMK2B phosphorylates the reticulon-homology domain of FAM134B, which enhances FAM134B oligomerization and activity in membrane fragmentation to accommodate high demand for ER-phagy. Unexpectedly, FAM134B G216R, a variant derived from a type II hereditary sensory and autonomic neuropathy (HSAN) patient, exhibits gain-of-function defects, such as hyperactive self-association and membrane scission, which results in excessive ER-phagy and sensory neuron death. Therefore, this study reveals a mechanism of ER membrane fragmentation in ER-phagy, along with a signaling pathway in regulating ER turnover, and suggests a potential implication of excessive selective autophagy in human diseases.
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Autofagia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Estresse do Retículo Endoplasmático , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Transdução de Sinais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Membrana Celular/metabolismo , Citocinese/fisiologia , Retículo Endoplasmático/metabolismo , Mutação com Ganho de Função , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lisossomos/metabolismo , Proteínas de Membrana/genética , PolimerizaçãoRESUMO
The scientific community is pursuing significant efforts worldwide to develop environmentally viable film materials from biomass, particularly transparent, high-performance regenerated cellulose (RC) films, to replace traditional plastics. However, the inferior mechanical performance and hydrophilic nature of RC films are generally not suitable for use as a substitute for plastics in practical applications. Herein, lignin homogenization is used to synthesize high-performance composite films. The esterified lignin nanoparticles (ELNPs) with dispersible and binding advantages are prepared through esterification and nanometrization. In the presence of ELNPs, RC films exhibit a higher tensile strength (110.4 MPa), hydrophobic nature (103.6° water contact angle, 36.6% water absorption at 120 min, and 1.127 × 10-12 g cm cm-2 s-1 Pa-1 water vapor permeability), and exciting optical properties (high visible and low ultraviolet transmittance). The films further display antioxidant activity, oxygen barrier ability, and thermostability. The films completely biodegrade at 12 and 30% soil moisture. Overall, this study offers new insights into lignin valorization and regenerated cellulose composite films as novel bioplastic materials.
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The exploration of a new conceptual strategy for improving the oxygen evolution reaction (OER) of earth-abundant electrocatalysts is critical. In this study, chiral copper oxide nanoflower is explored by a self-assembly method. The characterization suggests the chiral structure originates from the crystal plane-level helical stack of the secondary nanosheets. Of note, the assembly illustrates a record-high degree of spin polarization of 96%, indicating the ideal alignment of electron spin. Moreover, density function theory calculations show the chiral structure reducing the reaction energy barrier (REB) while switching the potential-determining step from *Oâ*OOH to *OHâ*O. Together with the enhanced electrochemical active surface area and accelerated charge transfer, the production of ground-state triplet O2 is improved via a spin-forbidden route that involves the singlet H2O/OHâ¢. Consequently, the chiral nanoflower shows a overpotential of 308 mV at 10 mA cm-2 and a Tafel slope of 93.5 mV dec-1, which is even superior to the commercial RuO2 (310 mV, 101 mV dec-1). This study presents a new strategy for improving the OER activity by simultaneously enhancing electronic properties and lowering the REB of an non-noble electrocatalyst via chirality engineering.
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Redox-active tetrathiafulvalene (TTF)-based covalent organic frameworks (COFs) exhibit distinctive electrochemical and photoelectrical properties, but their prevalent two-dimensional (2D) structure with densely packed TTF moieties limits the accessibility of redox center and constrains their potential applications. To overcome this challenge, an 8-connected TTF linker (TTF-8CHO) is designed as a new building block for the construction of three-dimensional (3D) COFs. This approach led to the successful synthesis of a 3D COF with the bcu topology, designated as TTF-8CHO-COF. In comparison to its 2D counterpart employing a 4-connected TTF linker, the 3D COF design enhances access to redox sites, facilitating controlled oxidation by I2 or Au3+ to tune physical properties. When irradiated with a 0.7 W cm-2 808 nm laser, the oxidized 3D COF samples ( I X - ${\mathrm{I}}_{\mathrm{X}}^{-}$ @TTF-8CHO-COF and Au NPs@TTF-8CHO-COF) demonstrated rapid temperature increases of 239.3 and 146.1 °C, respectively, which surpassed those of pristine 3D COF (65.6 °C) and the 2D COF counterpart (6.4 °C increment after I2 treatment). Furthermore, the oxidation of the 3D COF heightened its photoelectrical responsiveness under 808 nm laser irradiation. This augmentation in photothermal and photoelectrical response can be attributed to the higher concentration of TTF·+ radicals generated through the oxidation of well-exposed TTF moieties.
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Synergistic therapy has shown greater advantages compared with monotherapy. However, the complex multiple-administration plan and potential side effects limit its clinical application. A transformable specific-responsive peptide (TSRP) is utilized to one-step achieve synergistic therapy integrating anti-tumor, anti-angiogenesis and immune response. The TSRP is composed of: i) Recognition unit could specifically target and inhibit the biological function of FGFR-1; ii) Transformable unit could self-assembly and trigger nanofibers formation; iii) Reactive unit could specifically cleaved by MMP-2/9 in tumor micro-environment; iv) Immune unit, stimulate the release of immune cells when LTX-315 (Immune-associated oncolytic peptide) exposed. Once its binding to FGFR-1, the TSRP could cleaved by MMP-2/9 to form the nanofibers on the cell membrane, with a retention time of up to 12 h. Through suppressing the phosphorylation levels of ERK 1/2 and PI3K/AKT signaling pathways downstream of FGFR-1, the TSRP significant inhibit the growth of tumor cells and the formation of angioginesis. Furthermore, LTX-315 is exposed after TSRP cleavage, resulting in Calreticulin activation and CD8+ T cells infiltration. All above processes together contribute to the increasing survival rate of tumor-bearing mice by nearly 4-folds. This work presented a unique design for the biological application of one-step synergistic therapy of bladder cancer.
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Peptídeos , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/metabolismo , Animais , Humanos , Linhagem Celular Tumoral , Peptídeos/química , Peptídeos/farmacologia , Camundongos , Nanofibras/químicaRESUMO
IMPORTANCE: Gaining insight into the cell-entry mechanisms of swine acute diarrhea syndrome coronavirus (SADS-CoV) is critical for investigating potential cross-species infections. Here, we demonstrated that pretreatment of host cells with tunicamycin decreased SADS-CoV attachment efficiency, indicating that N-linked glycosylation of host cells was involved in SADS-CoV entry. Common N-linked sugars Neu5Gc and Neu5Ac did not interact with the SADS-CoV S1 protein, suggesting that these molecules were not involved in SADS-CoV entry. Additionally, various host proteases participated in SADS-CoV entry into diverse cells with different efficiencies. Our findings suggested that SADS-CoV may exploit multiple pathways to enter cells, providing insights into intervention strategies targeting the cell entry of this virus.
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Alphacoronavirus , Infecções por Coronavirus , Endopeptidases , Glicoproteínas , Doenças dos Suínos , Suínos , Internalização do Vírus , Animais , Alphacoronavirus/fisiologia , Infecções por Coronavirus/enzimologia , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Endopeptidases/metabolismo , Glicoproteínas/química , Glicoproteínas/metabolismo , Suínos/virologia , Doenças dos Suínos/enzimologia , Doenças dos Suínos/metabolismo , Doenças dos Suínos/virologia , Internalização do Vírus/efeitos dos fármacos , Tunicamicina/farmacologia , GlicosilaçãoRESUMO
BACKGROUND: Whether distributions and prognostic values of high-sensitivity cardiac troponin (hs-cTn) T and I are different across normoglycemic, prediabetic, and diabetic populations is unknown. METHODS: 10127 adult participants from the National Health and Nutrition Examination Survey 1999-2004 with determined glycemic status and measurement of at least one of hs-cTn assays were included, from whom healthy participants and presumably healthy diabetic and prediabetic participants were selected to investigate pure impacts of glycemic status on distributions of hs-cTn. The nonparametric method and bootstrapping were used to derive the 99th upper reference limits of hs-cTn and 95% CI. Participants with available follow-up and hs-cTn concentrations of all 4 assays were included in prognostic analyses. Associations of hs-cTn with all-cause and cardiac-specific mortality were modeled by Cox proportional hazard regression under the complex survey design. The incremental value of hs-cTn to an established risk score in predicting cardiac-specific mortality was assessed by the 10-year area under time-dependent receiver operating characteristic curve (AUC) using the Fine-Grey competing risk model. RESULTS: Among 9714 participants included in prognostic analyses, 5946 (61.2%) were normoglycemic, 2172 (22.4%) prediabetic, and 1596 (16.4%) diabetic. Hyperglycemic populations were older than the normoglycemic population but sex and race/ethnicity were similar. During the median follow-up of 16.8 years, hs-cTnT and hs-cTnI were independently associated with all-cause and cardiac-specific mortality across glycemic status. In the diabetic population, adjusted hazard ratios per 1-standard deviation increase of log-transformed hs-cTnT and hs-cTnI (Abbott) concentrations were 1.77 (95% CI 1.48-2.12; P < .001) and 1.83 (95% CI 1.33-2.53; P < .001), respectively, regarding cardiac-specific mortality. In the diabetic but not the normoglycemic population, adding either hs-cTnT (difference in AUC: 0.062; 95% CI 0.038-0.086; P < 0.001) or hs-cTnI (Abbott) (difference in AUC: 0.071; 95% CI 0.046-0.097; P < 0.001) would significantly increase the discriminative ability of the risk score; AUC of the score combined with hs-cTnT would be further improved by incorporating hs-cTnI (0.018; 95%CI 0.006-0.029; P = 0.002). The 99th percentile of hs-cTnT of the presumably healthy diabetic population was higher than the healthy population and had no overlap in 95% CIs, however, for hs-cTnI 99th percentiles of the two populations were very close and 95% CIs extensively overlapped. CONCLUSIONS: Hs-cTnT and hs-cTnI demonstrated consistent prognostic associations across glycemic status but incremental predictive values in hyperglycemic populations only. The susceptibility of hs-cTnT 99th percentiles to diabetes plus the additive value of hs-cTnI to hs-cTnT in diabetic cardiovascular risk stratification suggested hs-cTnI and hs-cTnT may be differentially associated with glycemic status, but further research is needed to illustrate the interaction between hyperglycemia and hs-cTn.
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Infarto do Miocárdio , Estado Pré-Diabético , Adulto , Humanos , Prognóstico , Troponina T , Infarto do Miocárdio/diagnóstico , Biomarcadores , Inquéritos Nutricionais , Estado Pré-Diabético/diagnóstico , Troponina IRESUMO
Topological modes (TMs) are typically localized at boundaries, interfaces and dislocations, and exponentially decay into the bulk of a large enough lattice. Recently, the non-Hermitian skin effect has been leveraged to delocalize the wave functions of TMs from the boundary and thus to increase the capacity of TMs dramatically. Here, we explore the capability of nonlinearity in designing and configuring the wave functions of TMs. With growing intensity, wave functions of these in-gap nonlinear TMs undergo an initial deviation from exponential decay, gradually merge into arbitrarily designable plateaus, then encompass the entire nonlinear domain, and eventually concentrate at the nonlinear boundary. Intriguingly, such extended nonlinear TMs are still robust against defects and disorders, and stable in dynamics under external excitation. Advancing the conceptual understanding of the nonlinear TMs, our results open new avenues for increasing the capacity of TMs and developing compact and configurable topological devices.
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The exotic physics associated with exceptional points (EPs) is always under the scrutiny of theoretical and experimental science. Recently, considerable effort has been invested in the combination of nonlinearity and non-Hermiticity. The concept of nonlinear EPs (NEPs) has been introduced, which can avoid the loss of completeness of the eigenbasis in dynamics while retaining the key features of linear EPs. Here, we present the first direct experimental demonstration of a NEP based on two non-Hermition coupled circuit resonators combined with a nonlinear saturable gain. At the NEP, the response of the eigenfrequency to perturbations demonstrates a third-order root law and the eigenbasis of the Hamiltonian governing the system dynamics is still complete. Our results bring this counterintuitive aspect of the NEP to light and possibly open new avenues for applications.
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Despite intensive studies in modeling neuropsychiatric disorders especially autism spectrum disorder (ASD) in animals, many challenges remain. Genetic mutant mice have contributed substantially to the current understanding of the molecular and neural circuit mechanisms underlying ASD. However, the translational value of ASD mouse models in preclinical studies is limited to certain aspects of the disease due to the apparent differences in brain and behavior between rodents and humans. Non-human primates have been used to model ASD in recent years. However, a low reproduction rate due to a long reproductive cycle and a single birth per pregnancy, and an extremely high cost prohibit a wide use of them in preclinical studies. Canine model is an appealing alternative because of its complex and effective dog-human social interactions. In contrast to non-human primates, dog has comparable drug metabolism as humans and a high reproduction rate. In this study, we aimed to model ASD in experimental dogs by manipulating the Shank3 gene as SHANK3 mutations are one of most replicated genetic defects identified from ASD patients. Using CRISPR/Cas9 gene editing, we successfully generated and characterized multiple lines of Beagle Shank3 (bShank3) mutants that have been propagated for a few generations. We developed and validated a battery of behavioral assays that can be used in controlled experimental setting for mutant dogs. bShank3 mutants exhibited distinct and robust social behavior deficits including social withdrawal and reduced social interactions with humans, and heightened anxiety in different experimental settings (n = 27 for wild-type controls and n = 44 for mutants). We demonstrate the feasibility of producing a large number of mutant animals in a reasonable time frame. The robust and unique behavioral findings support the validity and value of a canine model to investigate the pathophysiology and develop treatments for ASD and potentially other psychiatric disorders.
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Transtorno do Espectro Autista , Animais , Cães , Humanos , Transtorno do Espectro Autista/genética , Sistemas CRISPR-Cas/genética , Modelos Animais de Doenças , Edição de Genes , Proteínas dos Microfilamentos/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismoRESUMO
Uveal melanoma (UM) is the most common primary ocular malignancy in adults and has high mortality. Recurrence, metastasis, and therapeutic resistance are frequently observed in UM, but no beneficial systemic therapy is available, presenting an urgent need for developing effective therapeutic drugs. Verteporfin (VP) is a photosensitizer and a Yes-Associated Protein (YAP) inhibitor that has been used in clinical practice. However, VP's lack of tumor targetability, poor biocompatibility, and relatively low treatment efficacy hamper its application in UM management. Herein, we developed a biocompatible CD44-targeting hyaluronic acid nanoparticle (HANP) carrying VP (HANP/VP) to improve UM treatment efficacy. We found that HANP/VP showed a stronger inhibitory effect on cell proliferation than that of free VP in UM cells. Systemic delivery of HANP/VP led to targeted accumulation in the UM-tumor-bearing mouse model. Notably, HANP/VP mediated photodynamic therapy (PDT) significantly inhibited UM tumor growth after laser irradiation compared with no treatment or free VP treatment. Consistently, in HANP/VP treated tumors after laser irradiation, the tumor proliferation and YAP expression level were decreased, while the apoptotic tumor cell and CD8+ immune cell levels were elevated, contributing to effective tumor growth inhibition. Overall, the results of this preclinical study showed that HANP/VP is an effective nanomedicine for tumor treatment through PDT and inhibition of YAP in the UM tumor mouse model. Combining phototherapy and molecular-targeted therapy offers a promising approach for aggressive UM management.
Assuntos
Proliferação de Células , Ácido Hialurônico , Melanoma , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Neoplasias Uveais , Verteporfina , Verteporfina/farmacologia , Verteporfina/uso terapêutico , Animais , Fotoquimioterapia/métodos , Neoplasias Uveais/tratamento farmacológico , Neoplasias Uveais/patologia , Camundongos , Melanoma/tratamento farmacológico , Melanoma/patologia , Humanos , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/química , Linhagem Celular Tumoral , Nanopartículas/química , Proliferação de Células/efeitos dos fármacos , Ácido Hialurônico/química , Receptores de Hialuronatos/metabolismo , Apoptose/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas de Sinalização YAP , Camundongos Nus , Terapia de Alvo Molecular/métodos , Camundongos Endogâmicos BALB C , FemininoRESUMO
Oxidative cross-coupling is a powerful strategy to form C-heteroatom bonds. However, oxidative cross-coupling for constructing C-S bond is still a challenge due to sulfur overoxidation and poisoning transition-metal catalysts. Now, electrochemical redox relay using sulfur radicals formed in situ from inorganic sulfur source offers a solution to this problem. Herein, electrochemical redox relay-induced C-S radical cross-coupling of quinoxalinones and ammonium thiocyanate with bromine anion as mediator is presented. The electrochemical redox relay comprised initially the formation of sulfur radical via indirect electrochemical oxidation, simultaneous electrochemical reduction of the imine bond, electro-oxidation-triggered radical coupling involving dearomatization-rearomatization, and the reformation of the imine bond through anodic oxidation. Applying this strategy, various quinoxalinones bearing multifarious electron-deficient/-rich substituents at different positions were well compatible with moderate to excellent yields and good steric hindrance compatibility under constant current conditions in an undivided cell without transition-metal catalysts and additional redox reagents. Synthetic applications of this methodology were demonstrated through gram-scale preparation and follow-up transformation. Notably, such a unique strategy may offer new opportunities for the development of new quinoxalinone-core leads.