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Biological processes are typically actuated by dynamic multi-subunit molecular complexes. However, interactions between subunits, which govern the functions of these complexes, are hard to measure directly. Here, we develop a general approach combining cryo-EM imaging technology and statistical modeling and apply it to study the hexameric clock protein KaiC in Cyanobacteria. By clustering millions of KaiC monomer images, we identify two major conformational states of KaiC monomers. We then classify the conformational states of (>160,000) KaiC hexamers by the thirteen distinct spatial arrangements of these two subunit states in the hexamer ring. We find that distributions of the thirteen hexamer conformational patterns for two KaiC phosphorylation mutants can be fitted quantitatively by an Ising model, which reveals a significant cooperativity between neighboring subunits with phosphorylation shifting the probability of subunit conformation. Our results show that a KaiC hexamer can respond in a switch-like manner to changes in its phosphorylation level.
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Relógios Circadianos , Microscopia Crioeletrônica , Proteínas CLOCK , Análise por Conglomerados , Modelos EstatísticosRESUMO
Indacenodithiophene-benzothiadiazole (IDT-BT) has emerged as one of the most promising candidates for stretchable electronics due to its good stretchability and high mobility. Here, we present an air/liquid interface self-assembly method for the stretchable IDT-BT films and design an air-side transfer adherence strategy for improving the carrier mobility of IDT-BT. By controlling the cosolvent ratio in solution and the solvent evaporation rate, the large-scale intrinsically stretchable IDT-BT film with the diameter as high as â¼3 cm was self-assembled at the air/liquid interface. The resulting stretchable film with lightweight and good uniformity could be easily transferred to curved objects such as flexible 3 M tape, glass ball, and seashell. It is found that the transfer adherence strategy of the semiconductor film significantly affects the carrier transport. The transfer adherence from air-side can effectively decrease the number of the adsorbed water molecules at semiconductor/dielectric interface, which presents the mobility as high as 2.98 cm2 V-1 s-1. Based on the air/liquid interface self-assembled IDT-BT film, the peeling process of the film for preparation of full stretchable transistors could be eliminated. The resulting intrinsically stretchable transistor exhibits mobility higher than that of the transistor with a conventional spin-coated film. Our research provides new pathways for preparing the stretchable films and intrinsically stretchable organic field-effect transistors and shows the promising potential of the air/liquid interface self-assembly strategy for stretchable electronics.
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Chiral B/N embedded multi-resonance (MR) emitters open a new paradigm of circularly polarized (CP) organic light-emitting diodes (OLEDs) owing to their unique narrowband spectra. However, pure-red CP-MR emitters and devices remain exclusive in literature. Herein, by introducing a B-N covalent bond to lower the electron-withdrawing ability of the para-positioned B-π-B motif, we developed the first pair of pure-red double hetero-[n]helicenes (n = 6 and 7) CP-MR emitter peaking 617 nm with a small full-width at half-maximum of 38 nm and a high photoluminescence quantum yield of â¼100% in toluene. The intense mirror-image CP light produced by the enantiomers is characterized by high photoluminescence dissymmetry factors (gPL ) of +1.40/-1.41 × 10-3 from their stable helicenes configuration. The corresponding devices using these enantiomers afford impressive CP electroluminescence dissymmetry factors (gEL ) of +1.91/-1.77 × 10-3 , maximum external quantum efficiencies of 36.6%/34.4% and Commission Internationale de I'Éclairage coordinates of (0.67, 0.33), exactly satisfying the red-color requirement specified by National Television Standards Committee (NTSC) standard. Notably a remarkable long LT95 (operational time to 95% of the initial luminance) of approximately 400 hours at an initial brightness of 10,000 cd m-2 is also observed for the same device, representing the most stable CP-OLED up to date. This article is protected by copyright. All rights reserved.
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Water evaporation is a ubiquitous and spontaneous phase transition process. The utilization of solar-driven interface water evaporation that simultaneously obtains clean water and power generation can effectively alleviate people's concerns about fresh water and energy shortages. However, it remains a great challenge to efficiently integrate the required functions into the same device to reduce the complexity of the system and alleviate its dependence on solar energy to achieve full-time operation. In this work, a multifunctional device based on reduced graphene oxide (RGO)/Mn3 O4 /Al2 O3 composite nanomaterials is realized by an asymmetric strategy for effective solar-thermal-electro integration that can induce power generation by water evaporation in the presence/absence of light. Under one sun irradiation, the solar-driven evaporation rate and output voltage are 1.74 kg m-2 h-1 and 0.778 V, respectively. More strikingly, the nine-grid evaporation/power generation array integrated with multiple devices in series has the advantages of small volume, large evaporation area, and high power generation, and can light up light-emitting diodes (LEDs), providing the possibility for large-scale production and application. Based on the high photothermal conversion efficiency and power production capacity of the RGO/Mn3 O4 /Al2 O3 composite evaporation/generator, it will be a promising energy conversion device for future sustainable energy development and applications.
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Introduction: Cannabis is one of the most commonly used substances during pregnancy and has the potential to negatively impact parent-infant relationships. The prefrontal cortex (PFC) response to infant cues during pregnancy has been associated with subsequent positive parenting behaviors. However, PFC activation is altered in individuals who use cannabis. As the potency of cannabis has changed over the years, little is known about the specific role of cannabis use on gestational parent brain responses to infant cues. Materials and methods: Using functional Near-Infrared Spectroscopy (fNIRS) in the second trimester of pregnancy, we measured hemodynamic responses to an infant cry task and an infant faces task among individuals who were using cannabis (N = 14) and compared them with those who were not using cannabis (N = 45). For the infant cry task, pregnant individuals listened to cry sounds and matched white noise. For the infant faces task, they viewed happy, sad, and neutral faces. Results: There was no significant difference between the two groups after adjusting for multiple comparisons. Without adjusting for multiple comparisons, we found preliminary evidence for the differences in the dorsomedial PFC associated with heightened response to infant cry among individuals who use cannabis. The groups were also different in the dorsolateral PFC associated with decreased response to infant sad faces among individuals who use cannabis. Discussion: Our preliminary data suggests that cannabis use during pregnancy was associated with brain activation in the regions involved in the emotional regulation and information processes. However, the results did not survive after adjustment for multiple comparisons, thus future research with larger sample sizes is needed to confirm potential differences in brain function among cannabis-using pregnant individuals.
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In a solid-state photonics-based Lidar, all essential components can be integrated into a silicon chip. It is simple and effective to use a tunable laser source to implement Lidar's beam steering. However, how to effectively increase the steering angle in a small wavelength tuning range is usually a key challenge due to the limited material and waveguide dispersion. In Silicon-on-insulator waveguide, we design a novel solid-state Lidar using two trans-electrical (TE) polarized beams counter-propagating towards each other. Two corresponding output beams from just a single grating coupler (GC) can be seamlessly combined to double the beam steering angle. Furthermore, a low-priced solid-state Lidar is designed for TE polarized beams counter-propagating towards each other by using wavelength division multiplexed laser array.
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We aimed to compare the effects of three intensities of treadmill running on exercise-induced hypoalgesia (EIH) in healthy individuals. We anticipated that the primary and secondary changes in pain perception and modulation may differ between running intensities. Sixty-six women were randomly assigned to one of three treadmill running intensities for 35 min: 40% reserved heart rate (HRR), 55% HRR, or 70% HRR. The effects of EIH were assessed using pressure pain thresholds (PPT) and tolerance thresholds (PPTol). We measured conditional pain modulation (CPM). Compared with baseline, PPT and PPTol significantly increased in all groups during running and at the 5-10-min follow-up. The PPT and PPTol changes in the moderate- and low-intensity groups were significantly higher than those in the high-intensity group during running and 24 h after running, while the CPM responses of the high-intensity group were significantly reduced at the 24-h follow-up. Moderate- and low-intensity running may elicit significant primary and secondary (persisting over 24 h) EIH effects and increase CPM responses in females. However, high-intensity running induced only limited analgesic effects and reduced CPM responses, which may be attributed to the activation of endogenous pain modulation.
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BACKGROUND: Primary biliary cholangitis (PBC) is a chronic progressive autoimmune cholestatic disease. The main target organ of PBC is the liver, and nonsuppurative inflammation of the small intrahepatic bile ducts may eventually develop into cirrhosis or liver fibrosis. AIM: To explore the clinical characteristics of early-stage PBC, identify PBC in the early clinical stage, and promptly treat and monitor PBC. METHODS: The data of 82 patients with PBC confirmed by pathology at Tianjin Second People's Hospital from January 2013 to November 2021 were collected, and the patients were divided into stage I, stage II, stage III, and stage IV according to the pathological stage. The general data, serum biochemistry, immunoglobulins, and autoimmune antibodies of patients in each stage were retrospectively analyzed. RESULTS: In early-stage (stages I + II) PBC patients, 50.0% of patients had normal alanine aminotransferase (ALT) levels, and 37.5% had normal aspartate aminotransferase (AST) levels. For the remaining patients, the ALT and AST levels were mildly elevated; all of these patients had levels of < 3 times the upper limit of normal values. The AST levels were significantly different among the three groups (stages I + II vs stage III vs stage IV, P < 0.05). In the early stage, 29.2% of patients had normal alkaline phosphatase (ALP) levels. The remaining patients had different degrees of ALP elevation; 6.3% had ALP levels > 5 times the upper limit of normal value. Moreover, γ-glutamyl transferase (GGT) was more robustly elevated, as 29.2% of patients had GGT levels of > 10 times the upper limit of normal value. The ALP values among the three groups were significantly different (P < 0.05). In early stage, the jaundice index did not increase significantly, but it gradually increased with disease progression. However, the above indicators were significantly different (P < 0.05) between the early-stage group and the stage IV group. With the progression of the disease, the levels of albumin and albumin/globulin ratio tended to decrease, and the difference among the three groups was statistically significant (P < 0.05). In early-stage patients, IgM and IgG levels as well as cholesterol levels were mildly elevated, but there were no significant differences among the three groups. Triglyceride levels were normal in the early-stage group, and the differences among the three groups were statistically significant (P < 0.05). The early detection rates of anti-mitochondria antibody (AMA) and AMA-M2 were 66.7% and 45.8%, respectively. The positive rate of anti-sp100 antibodies was significantly higher in patients with stage IV PBC. When AMA and AMA-M2 were negative, in the early stage, the highest autoantibody was anti-nuclear antibody (ANA) (92.3%), and in all ANA patterns, the highest was ANA centromere (38.5%). CONCLUSION: In early-stage PBC patients, ALT and AST levels are normal or mildly elevated, GGT and ALP levels are not elevated in parallel, GGT levels are more robustly elevated, and ALP levels are normal in some patients. When AMA and AMA-M2 are negative, ANA especially ANA centromere positivity suggests the possibility of early PBC. Therefore, in the clinic, significantly elevated GGT levels with or without normal ALP levels and with ANA (particularly ANA centromere) positivity (when AMA and AMA-M2 are negative) may indicate the possibility of early PBC.
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Doenças Autoimunes , Cirrose Hepática Biliar , Humanos , Autoanticorpos , Cirrose Hepática Biliar/diagnóstico , Estudos Retrospectivos , Albuminas , BiomarcadoresRESUMO
Pyrin, a protein encoded by the MEFV gene, plays a vital role in innate immunity by sensing modifications in Rho GTPase and assembling the pyrin inflammasome, which in turn activates downstream immune responses. We identified a novel and de novo MEFV p.E583A dominant variant in three patients from a family, distinct from the previously reported S242 and E244 sites. These patients exhibited a phenotype that diverged from those resulting from classical MEFV gene mutations, characterized by the absence of recurrent fever but the presence of recurrent chest and abdominal pain. Colchicine effectively controlled the phenotype, and the mutation was found to induce pyrin inflammasome assembly and activation in patients' peripheral blood mononuclear cells (PBMCs) and cell lines. Mechanistically, truncation experiments revealed that the E583A variant impacted the autoinhibitory structure of pyrin. Our study offers new insights into the mechanisms underlying pyrin inflammasome activation.
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BACKGROUND: Chronic pancreatitis (CP) is a fibroinflammatory syndrome leading to reduced quality of life and shortened life expectancy. Population-based estimates of the incidence, prevalence, and comorbidities of CP in China are scarce. AIM: To characterize the incidence, prevalence, and comorbidities of CP in Sichuan Province, China, with population-based data. METHODS: Data on CP from 2015 to 2021 were obtained from the Health Information Center of Sichuan Province. During the study period, a total of 38090 individuals were diagnosed with CP in Sichuan Province. The yearly incidence rate and point prevalence rate (December 31, 2021) of CP were calculated. The prevalence of comorbid conditions in CP patients was estimated. The annual number of CP-related hospitalizations, hospital length of stay, and hospitalization costs for CP were evaluated. Yearly incidence rates were standardized for age by the direct method using the permanent population of Sichuan Province in the 2020 census as the standard population. An analysis of variance test for the linearity of scaled variables and the Cochran-Armitage trend test for categorical data were performed to investigate the yearly trends, and a two-sided test with P < 0.05 was considered statistically significant. RESULTS: The 38090 CP patients comprised 23280 males and 14810 females. The mean age of patients at CP diagnosis was 57.83 years, with male patients (55.87 years) being younger than female patients (60.11 years) (P < 0.001). The mean incidence rate of CP during the study period was 6.81 per 100000 person-years, and the incidence of CP increased each year, from 4.03 per 100000 person-years in 2015 to 8.27 per 100000 person-years in 2021 (P < 0.001). The point prevalence rate of CP in 2021 was 45.52 per 100000 individuals for the total population, with rates of 55.04 per 100000 individuals for men and 35.78 per 100000 individuals for women (P < 0.001). Individuals aged 65 years or older had the highest prevalence of CP (113.38 per 100000 individuals) (P < 0.001). Diabetes (26.32%) was the most common comorbidity in CP patients. The number of CP-related hospitalizations increased from 3739 in 2015 to 11009 in 2021. The total costs for CP-related hospitalizations for CP patients over the study period were 667.96 million yuan, with an average of 17538 yuan per patient. CONCLUSION: The yearly incidence of CP is increasing, and the overall CP hospitalization cost has increased by 1.4 times during the last 7 years, indicating that CP remains a heavy health burden.
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Pancreatite Crônica , Qualidade de Vida , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Prevalência , Incidência , Comorbidade , Pancreatite Crônica/epidemiologiaRESUMO
Natural phosphorus-ferromanganese ore (NPO-NFMO) based composites by mechanical ball milling method, applying for the simultaneous remediation of arsenic (As) and lead (Pb) co-contaminated groundwater. Kinetic behavior adopted pseudo-second-order adsorption mechanism attaining equilibrium in 120 min over a wide pH range (2.0-6.0). NPO-NFMO realized higher adsorption capacity for As(III) (6.8 mg g-1) and Pb(II) (26.5 mg g-1) than those of single NPO (1.7 and 7.8 mg g-1) and NFMO (2.9 and 5.1 mg g-1), indicating that synergistic effects of NPO and NFMO considerably enhanced the adsorption capacity in mixed adsorption system. Fresh and used NPO-NFMO were characterized, and indicated that NPO-NFMO formed stable minerals of PbAs2O6 and PbFe2(AsO4)2(OH)2. The underlying adsorption mechanism indicated that As(III) and Pb(II) removal was involved with multiple mechanisms, including electrostatic adsorption, oxidation, complexation, and coprecipitation. The effects of key reaction parameters including mass ratios of NPO and NFMO, initial metal ion concentration, dosage, solution pH, and co-existing anions in groundwater were systematically investigated. The novel designed NPO-NFMO-based composites can be deemed as a promising amendment for simultaneous immobilization of As(III) and Pb(II) in co-contaminated soil and groundwater.
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BACKGROUND AND AIM: The literature is sparse on the association between serum liver fibrosis markers and the development of hepatic decompensation in patients with compensated cirrhosis. We aimed to assessed whether the serum liver fibrosis markers are predictive of the occurrence of hepatic decompensation. METHODS: We ascertained 688 cirrhotic patients with varying etiologies, between December 2015 to December 2019. Serum hyaluronic acid (HA), laminin (LN), collagen IV (CIV), and N-terminal propeptide of type III collagen (PIIINP) levels were measured at enrollment. All subjects were followed for at least 6 months for occurrence of hepatic decompensation. Cox proportional hazard regression models were used to estimate the hazard ratios (HRs) of hepatic decompensation during follow-up. RESULTS: During a median follow-up of 22.0 (13.0-32.0) months, decompensation occurred in 69 (10.0%) patients. Multivariate analysis indicated that higher LN (HR: 1.008, 95% confidence interval [CI]: 1.002-1.014, P = 0.011) and CIV (HR: 1.004, 95% CI: 1.001-1.007, P = 0.003) levels were independently associated with hepatic decompensation. Furthermore, patients in the tertile 2 and tertile 3 groups for CIV levels had HRs of 4.787 (1.419, 16.152) (P = 0.012) and 5.153 (1.508, 17.604) (P = 0.009), respectively, for occurrence of decompensation event compared with those in the tertile 1 group. CONCLUSION: Serum liver fibrosis markers, particularly in CIV, appeared to be reliable biomarkers of disease progression and liver decompensation in patients with compensated cirrhosis with varying etiologies.
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Cirrose Hepática , Falência Hepática , Humanos , Cirrose Hepática/complicações , Biomarcadores , Progressão da DoençaRESUMO
Background: Gliomas, the most prevalent primary malignant tumors of the central nervous system in adults, exhibit slow growth in lower-grade gliomas (LGG). However, the majority of LGG cases progress to high-grade gliomas, posing challenges for prognostication. The tumor microenvironment (TME), characterized by telomere-related genes and immune cell infiltration, strongly influences glioma growth and therapeutic response. Therefore, our objective was to develop a Telomere-TME (TM-TME) classifier that integrates telomere-related genes and immune cell landscape to assess prognosis and therapeutic response in glioma. Methods: This study encompassed LGG patients from the TCGA and CCGA databases. TM score and TME score were derived from the expression signatures of telomere-related genes and the presence of immune cells in LGG, respectively. The TM-TME classifier was established by combining TM and TME scores to effectively predict prognosis. Subsequently, we conducted Kaplan-Meier survival estimation, univariate Cox regression analysis, and receiver operating characteristic curves to validate the prognostic prediction capacity of the TM-TME classifier across multiple cohorts. Gene Ontology (GO) analysis, biological processes, and proteomaps were performed to annotate the functional aspects of each subgroup and visualize the cellular signaling pathways. Results: The TM_low+TME_high subgroup exhibited superior prognosis and therapeutic response compared to other subgroups (P<0.001). This finding could be attributed to distinct tumor somatic mutations and cancer cellular signaling pathways. GO analysis indicated that the TM_low+TME_high subgroup is associated with the neuronal system and modulation of chemical synaptic transmission. Conversely, the TM_high+TME_low subgroup showed a strong association with cell cycle and DNA metabolic processes. Furthermore, the classifier significantly differentiated overall survival in the TCGA LGG cohort and served as an independent prognostic factor for LGG patients in both the TCGA cohort (P<0.001) and the CGGA cohort (P<0.001). Conclusion: Overall, our findings underscore the significance of the TM-TME classifier in predicting prognosis and immune therapeutic response in glioma, shedding light on the complex immune landscape within each subgroup. Additionally, our results suggest the potential of integrating risk stratification with precision therapy for LGG.
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Glioma , Telômero , Adulto , Humanos , Prognóstico , Biomarcadores , Telômero/genética , Glioma/diagnóstico , Glioma/genética , Glioma/terapia , Sistema Nervoso Central , Microambiente Tumoral/genéticaRESUMO
Titanium-based implants often lead to premature implant failure due to the lack of antimicrobial, osteogenic, and angiogenic properties. To this end, a new strategy was developed to fabricate CaO2@ZIF-67-HA-ADH coating on titanium surfaces by combining calcium peroxide (CaO2) nanoparticles, zeolite imidazolate framework-67 (ZIF-67), and the chemical coupling hyaluronic acid-adipic acid dihydrazide (HA-ADH). We characterized CaO2@ZIF-67-HA-ADH with scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results demonstrated that CaO2@ZIF-67-HA-ADH was pH-sensitive and decomposed rapidly under acidic conditions, and it released inclusions slowly under neutral conditions. Antibacterial experiments showed that the CaO2@ZIF-67-HA-ADH coating had excellent antibacterial properties and effectively killed methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PAO-1). Cell experiments revealed that the CaO2@ZIF-67-HA-ADH coating promoted pro-osteoblast adhesion, proliferation, and differentiation and also promoted the migration and angiogenesis of human umbilical vein endothelial cells (HUVECs), exhibiting excellent osteogenic and angiogenic properties. In in vivo animal implantation experiments, the CaO2@ZIF-67-HA-ADH coating exhibited strong antimicrobial activity early after implantation and excellent osseointegration later after implantation. In conclusion, the pH-responsive CaO2@ZIF-67-HA-ADH coating conferred excellent antibacterial, osteogenic, and angiogenic properties to titanium implants, which effectively enhanced osseointegration of the implants and prevented bacterial infection; the coating shows promise for use in the treatment of bone defects.
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Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Zeolitas , Animais , Humanos , Ácido Hialurônico , Titânio/farmacologia , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Células Endoteliais da Veia Umbilical Humana , Concentração de Íons de HidrogênioRESUMO
Seoul virus (SEOV) is a major pathogen which causes hemorrhagic fever with renal syndrome (HFRS), and is present all over the world. However, there are currently few long-term systematic studies of SEOV's phylogenetic and evolutionary mechanisms in epidemic areas. Thus, in this study, we used RT-PCR combined with NGS to obtain the genomes of six SEOV viruses from 1993, as well as 56 Hebei province-specific tissue samples from 1999 to 2022. Phylogenetic analysis showed that the SEOV samples could be divided into seven groups and showed geographic clustering. The geographic region may be the main factor affecting the genetic diversity of SEOV. We also found that SEOV was subject to strong overall purifying selection and positive selection at certain sites during evolution. Recombination events and high nucleotide substitution rates were also shown to accelerate SEOV's evolution. Evolutionary feature of the L segment is more representative of complete genome. Our detailed analysis provides a deeper understanding of the genetic diversity and evolutionary drivers of SEOV within its primary epidemic areas. It will be important to further monitor epidemiological trends and drivers of variation to help increase our understanding of the pathogenicity of SEOV infections.
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Skeletal characteristics are important to the growth and development of poultry. In feeding management, constant free feeding (FF) of poultry may lead to imbalance between bone development and weight gain. Feed restriction (FR), to a certain extent, is one way to solve this problem. However, the effect of feed restriction on poultry bone development needs further elucidation at the molecular level. Therefore, in the present study, we investigated the effects of different levels of feed restriction (60% FR, 70% FR, 80% FR, and FF) on the sternum development of ducks at 7 and 8 wk old. In the seventh wk, with increasing feed restriction, the values of traits including body weight, breast muscle weight, sternal weight, keel length, and calcified keel length decreased. However, in the eighth wk, the sternum weight and keel length of ducks treated with 60% FR were unexpectedly higher than those of FF individuals, indicative of catch-up growth. Then, we conducted RNA-seq and metabolomic analysis on sterna from 7- and 8-wk-old FF and 60% FR ducks. The results identified multiple differentially expressed genes (DEGs) associated with sternum development that were influenced by feed restriction. Among them, we found that the mRNA expression levels of the chondroitin sulfate synthase 3 (CHSY3) and annexin A2 (ANXA2) which are involved in glycosaminoglycan biosynthesis and bone mineralization, had smaller changes over time under FR treatment than under FF treatment, implying that the FR treatment to a certain extent prevented the premature calcification and prolonged the development time of duck sternum. In addition, the metabolomic and integrative analyses revealed that several antiaging-related metabolites and genes were associated with sternal catch-up growth. Pyrimidine metabolism was identified as the most significant pathway in which most differential metabolites (DMs) between FF and 60% FR were enriched. The results from integrative analysis revealed that the content and expression of 4-aminobutyric acid (GABA) and its related genes showed relatively higher activity in the 60% FR group than in the FF group. The present study identifies multiple biomarkers associated with duck sternum development that are influenced by feed restriction and suggests the potential mechanism of feed restriction-associated duck sternal catch-up growth.
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Patos , Transcriptoma , Humanos , Animais , Patos/fisiologia , Galinhas/genética , Calcificação Fisiológica , Esterno , Ração Animal/análiseRESUMO
Two new three-dimensional (3D) polyoxometalate-based metal-organic frameworks (POMOFs), [M2(btap)4(H2O)4(HPMo10VI Mo2VO40)] (M = Co (1) and Cd (2); btap = 3, 5-bis(1', 2', 4'-triazol-1'-yl)pyridine), have been synthesized under mild hydrothermal conditions and characterized in detail. Single-crystal X-ray diffraction (SXRD) analysis indicates that 1 and 2 are isostructural. In complexes 1 and 2, the metal ion is coordinated with the ligand to form two different left and right helical one-dimensional chains, which are alternately connected in a twisted form to build a two-fold interpenetrated three-dimensional structure, and the polyoxometalate is encapsulated into in the pores generated by the interpenetrating structure. It is noteworthy that 1 and 2, as recyclable catalysts, possess favorable heterogeneous catalytic activity and excellent sulfoxide selectivity in sulfide oxidation reactions, with H2O2 as an oxidant. By reason of the high dispersion of polyoxometalate with good intrinsic activity in the skeleton structure, the title complex has high activity. In addition, no obvious decrease of sulfoxide yield is observed after at least five cycles. These results indicate the excellent catalytic activity and sustainability of 1 and 2.
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Retinal ganglion cells (RGCs), the sole output neurons in the eyes, are vulnerable to diverse insults in many pathological conditions, which can lead to permanent vision dysfunction. However, the molecular and cellular mechanisms that contribute to protecting RGCs and their axons from injuries are not completely known. Here, we identify that Porf-2, a member of the Rho GTPase activating protein gene group, is upregulated in RGCs after optic nerve crush. Knockdown of Porf-2 protects RGCs from apoptosis and promotes long-distance optic nerve regeneration after crush injury in both young and aged mice in vivo. In vitro, we find that inhibition of Porf-2 induces axon growth and growth cone formation in retinal explants. Inhibition of Porf-2 provides long-term and post-injury protection to RGCs and eventually promotes the recovery of visual function after crush injury in mice. These findings reveal a neuroprotective impact of the inhibition of Porf-2 on RGC survival and axon regeneration after optic nerve injury, providing a potential therapeutic strategy for vision restoration in patients with traumatic optic neuropathy.
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Lesões por Esmagamento , Traumatismos do Nervo Óptico , Traumatismos dos Nervos Periféricos , Animais , Camundongos , Traumatismos do Nervo Óptico/genética , Axônios , Regeneração Nervosa , Retina , Nervo Óptico , Células Ganglionares da Retina , Lesões por Esmagamento/genéticaRESUMO
Patterning antidots, which are regions of potential hills that repel electrons, into well-defined antidot lattices creates fascinating artificial periodic structures, leading to anomalous transport properties and exotic quantum phenomena in two-dimensional systems. Although nanolithography has brought conventional antidots from the semiclassical regime to the quantum regime, achieving precise control over the size of each antidot and its spatial period at the atomic scale has remained challenging. However, attaining such control opens the door to a new paradigm, enabling the creation of quantum antidots with discrete quantum hole states, which, in turn, offer a fertile platform to explore novel quantum phenomena and hot electron dynamics in previously inaccessible regimes. Here we report an atomically precise bottom-up fabrication of a series of atomic-scale quantum antidots through a thermal-induced assembly of a chalcogenide single vacancy in PtTe2. Such quantum antidots consist of highly ordered single-vacancy lattices, spaced by a single Te atom, reaching the ultimate downscaling limit of antidot lattices. Increasing the number of single vacancies in quantum antidots strengthens the cumulative repulsive potential and consequently enhances the collective interference of multiple-pocket scattered quasiparticles inside quantum antidots, creating multilevel quantum hole states with a tunable gap from the telecom to far-infrared regime. Moreover, precisely engineered quantum hole states of quantum antidots are geometry protected and thus survive on oxygen substitutional doping. Therefore, single-vacancy-assembled quantum antidots exhibit unprecedented robustness and property tunability, positioning them as highly promising candidates for advancing quantum information and photocatalysis technologies.