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BACKGROUND: Single-cell chromatin accessibility assays, such as scATAC-seq, are increasingly employed in individual and joint multi-omic profiling of single cells. As the accumulation of scATAC-seq and multi-omics datasets continue, challenges in analyzing such sparse, noisy, and high-dimensional data become pressing. Specifically, one challenge relates to optimizing the processing of chromatin-level measurements and efficiently extracting information to discern cellular heterogeneity. This is of critical importance, since the identification of cell types is a fundamental step in current single-cell data analysis practices. RESULTS: We benchmark 8 feature engineering pipelines derived from 5 recent methods to assess their ability to discover and discriminate cell types. By using 10 metrics calculated at the cell embedding, shared nearest neighbor graph, or partition levels, we evaluate the performance of each method at different data processing stages. This comprehensive approach allows us to thoroughly understand the strengths and weaknesses of each method and the influence of parameter selection. CONCLUSIONS: Our analysis provides guidelines for choosing analysis methods for different datasets. Overall, feature aggregation, SnapATAC, and SnapATAC2 outperform latent semantic indexing-based methods. For datasets with complex cell-type structures, SnapATAC and SnapATAC2 are preferred. With large datasets, SnapATAC2 and ArchR are most scalable.
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Benchmarking , Cromatina , Análisis de la Célula Individual , Análisis de la Célula Individual/métodos , Cromatina/genética , Cromatina/metabolismo , Humanos , Biología Computacional/métodosRESUMEN
Near-infrared (NIR) light, valuable for its biological penetration and invisibility to the human eye, is a crucial tool in biomedicine, environmental monitoring, anticounterfeiting, and information encryption, yet traditional NIR luminescent materials are often unstable in humid conditions. Here, a highly stable MgGeO3:Mn2+ glass ceramic (GC) with NIR luminescence was successfully synthesized. As-obtained GC700 boasts exceptional luminescent capabilities and possesses abundant trap structures, enabling data inscription with a 405 nm laser and retrieval via laser/thermal excitation. Moreover, the emission peak of Mn2+ can be manipulated from 630 to 691 nm by increasing the annealing treatment temperature. With the harnessing of the effective NIR emission, stable carrier characteristics, and numerous trap structures, there is potential for application in information encryption. Accordingly, we explored the application of MgGeO3:Mn2+ GC (GC700 and GC800) samples in precious three-dimensional (3D) information storage and NIR mechanoluminescence (ML) for biological tissue imaging. These applications demonstrate the potential and versatility of electron-capturing NIR luminescent materials in a range of cutting-edge fields.
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Aging is the major risk factor for most human diseases and represents a major socio-economical challenge for modern societies. Despite its importance, the process of aging remains poorly understood. Epigenetic dysregulation has been proposed as a key driver of the aging process. Modifications in transcriptional networks and chromatin structure might be central to age-related functional decline. A prevalent feature described during aging is the overall reduction in heterochromatin, specifically marked by the loss of repressive histone modification, Histone 3 lysine 9 trimethylation (H3K9me3). However, the role of H3K9me3 in aging, especially in mammals, remains unclear. Here we show using a novel mouse strain, (TKOc), carrying a triple knockout of three methyltransferases responsible for H3K9me3 deposition, that the inducible loss of H3K9me3 in adulthood results in premature aging. TKOc mice exhibit reduced lifespan, lower body weight, increased frailty index, multi-organ degeneration, transcriptional changes with significant upregulation of transposable elements, and accelerated epigenetic age. Our data strongly supports the concept that the loss of epigenetic information directly drives the aging process. These findings reveal the importance of epigenetic regulation in aging and suggest that interventions targeting epigenetic modifications could potentially slow down or reverse age-related decline. Understanding the molecular mechanisms underlying the process of aging will be crucial for developing novel therapeutic strategies that can delay the onset of age-associated diseases and preserve human health at old age specially in rapidly aging societies.
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Due to the sensitivity to water, the all-inorganic CsPbBr3 nanocrystals have been widely applied in information encryption with spatial dimensions. However, the absence of time-dimension information limits the information capacity for the application of CsPbBr3. In this work, the CsPbBr3 nanocrystal was combined with water-sensitive borophosphate glass, achieving decomposing/recrystallization of CsPbBr3 nanocrystal with multi-dimension. The addition of SiO2 confirms that the collapse of the borophosphate glass network structure causes the exposure of the CsPbBr3 nanocrystals. The decomposition and recrystallization mechanism of CsPbBr3 nanocrystals in glass-ceramics upon encountering water has been verified. Finally, an information encryption strategy, using the mixture of CsPbBr3 glass ceramic and sodium carboxymethylcellulose as ink, is designed via adopting screen-printing technology, which not only provides a new idea for the preparation of CsPbBr3 nanocrystals, but also establish a new avenue for the information encryption technology.
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Intravenous injectable metformin-Cu(II)-EGCG infinite coordination polymer nanoparticles (metformin-Cu(II)-EGCG ICP NPs) have been synthesized, and an efficient strategy for synergistic tumor therapy by utilizing these nanoparticles in conjunction with micro-electrothermal needles (MENs) was proposed. These nanoparticles display exceptional uniformity with a diameter of 117.5 ± 53.3 nm, exhibit an extraordinary drug loading capacity of 90% and allow for precise control over the drug ratio within the range of 1 : 1 to 1 : 20 while maintaining excellent thermal stability. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction were employed to determine their chemical structure and coordination state. The combination index (CI) value of the metformin-Cu(II)-EGCG ICP NPs was calculated to be 0.19, surpassing that of the two individual drugs and metformin mixed with EGCG (0.98). Importantly, upon intravenous injection, metformin in nanoparticles demonstrated exceptional stability in the bloodstream, while both drugs were rapidly released within the acidic tumor microenvironment. Animal experiments showcased an impressive tumor inhibition rate of 100% within a mere 20-day time frame after the synergistic therapy with a lower dosage (5.0 mg kg-1 of nanoparticles), coupled with a minimal tumor recurrence rate of only 18.75% over a 60-day observation period. These findings indicate the promising prospects of these nanoparticles in tumor treatment.
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Antineoplásicos , Cobre , Metformina , Nanopartículas , Polímeros , Metformina/química , Metformina/farmacología , Metformina/administración & dosificación , Nanopartículas/química , Animales , Cobre/química , Ratones , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/administración & dosificación , Polímeros/química , Humanos , Inyecciones Intravenosas , Tamaño de la Partícula , Ratones Endogámicos BALB C , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Línea Celular TumoralRESUMEN
The pathogenesis of Parkinson's disease (PD) has been associated with mitochondrial dysfunction. Given that the PINK1/Parkin pathway governs mitochondrial quality control by inducing mitophagy to remove damaged mitochondria, therapeutic approaches to activate PINK1/Parkin-mediated mitophagy have the potential in the treatment of PD. Here, we have identified a new small molecule, BL-918, as an inducer of mitophagy via activating the PINK1/Parkin pathway. BL-918 triggers PINK1 accumulation and Parkin mitochondrial translocation to initiate PINK1/Parkin-mediated mitophagy. We found that mitochondrial membrane potential and mitochondrial permeability transition pore were involved in BL-918-induced PINK1/Parkin pathway activation. Moreover, we showed that BL-918 mitigated PD progression in MPTP-induced PD mice in a PINK1-dependent manner. Our results unravel a new activator of the PINK1/Parkin signaling pathway and provide a potential strategy for the treatment of PD and other diseases with dysfunctional mitochondria.
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Computational biologists are frequently engaged in collaborative data analysis with wet lab researchers. These interdisciplinary projects, as necessary as they are to the scientific endeavor, can be surprisingly challenging due to cultural differences in operations and values. In this Ten Simple Rules guide, we aim to help dry lab researchers identify sources of friction and provide actionable tools to facilitate respectful, open, transparent, and rewarding collaborations.
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Biología Computacional , Conducta Cooperativa , Investigadores , HumanosRESUMEN
Bacteria-infected wounds healing has been greatly hindered by antibiotic resistance and persistent inflammation. It is crucial to develop multifunctional nanocomposites that possess effective antibacterial properties and can simultaneously accelerate the wound healing process to overcome the above challenges. Herein, we prepared a yolk-shell structured Ag nanowires (NWs)@amorphous hollow ZIF-67 by etching ZIF-67 onto the Ag NWs for infected wound healing for the first time. The etched hollow structure of amorphous ZIF-67 in the nanocomposite makes it a promising platform for loading healing-promoting drugs. We extensively studied the antibacterial and healing-promoting properties of the curcumin (CCM)-loaded nanocomposite (Ag NWs@C-HZ67). Ag NWs, being noble metal materials with plasmonic effects, can absorb a broad range of natural light and convert it to thermal energy. This photothermal conversion further improves the release of antibacterial components and wound healing drugs when exposed to light. During the healing process of an infected wound, Ag and Co ions were released from Ag NWs@C-HZ67 upon direct contact with the wound exudate and under the influence of light irradiation. Simultaneously, the loaded CCM leaked out to repair the infected wound. The minimum inhibitory concentrations of the Ag NWs@C-HZ67 groups against Escherichia coli and Staphylococcus aureus bacteria decreased to 3 and 3 µg ml-1 when exposed to white light. Furthermore, an in vivo assessment of infected wound healing demonstrated that combining Ag NWs@C-HZ67 with light significantly accelerated the wound healing process, achieving 70% healing by the 6th day and almost complete healing by the 8th day. This advanced nanocomposite, consisting of components that possess antibacterial and growth-promoting properties, offers a safe, effective and clinically-translatable solution for accelerating the healing process of infected wounds.
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Accumulated reactive oxygen species (ROS) and their resultant vascular dysfunction in androgenic alopecia (AGA) hinder hair follicle survival and cause permanent hair loss. However, safe and effective strategies to rescue hair follicle viability to enhance AGA therapeutic efficiency remain challenging. Herein, we fabricated a quercetin-encapsulated (Que) and polydopamine-integrated (PDA@QLipo) nanosystem that can reshape the perifollicular microenvironment to initial hair follicle regeneration for AGA treatment. Both the ROS scavenging and angiogenesis promotion abilities of PDA@QLipo were demonstrated. In vivo assays revealed that PDA@QLipo administrated with roller-microneedles successfully rejuvenated the "poor" perifollicular microenvironment, thereby promoting cell proliferation, accelerating hair follicle renewal, and facilitating hair follicle recovery. Moreover, PDA@QLipo achieved a higher hair regeneration coverage of 92.5% in the AGA mouse model than minoxidil (87.8%), even when dosed less frequently. The nanosystem creates a regenerative microenvironment by scavenging ROS and augmenting neovascularity for hair regrowth, presenting a promising approach for AGA clinical treatment.
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Alopecia , Folículo Piloso , Indoles , Polímeros , Quercetina , Especies Reactivas de Oxígeno , Alopecia/tratamiento farmacológico , Alopecia/patología , Quercetina/farmacología , Quercetina/administración & dosificación , Quercetina/química , Animales , Indoles/química , Indoles/farmacología , Folículo Piloso/efectos de los fármacos , Folículo Piloso/crecimiento & desarrollo , Polímeros/química , Ratones , Especies Reactivas de Oxígeno/metabolismo , Regeneración/efectos de los fármacos , Humanos , Cabello/efectos de los fármacos , Cabello/crecimiento & desarrollo , Proliferación Celular/efectos de los fármacos , Microambiente Celular/efectos de los fármacos , Modelos Animales de Enfermedad , MasculinoRESUMEN
Terahertz (THz) waves have garnered significant interest across various fields, particularly in high-sensitivity sensing applications. Metamaterials can be employed in THz sensors, specifically for refractive index sensing and pesticide detection due to their high-sensitivity characteristics. In this Article, a dual-band flexible THz metamaterial sensor based on polyimide is proposed for refractive index and pesticide sensing, which is fabricated using ultraviolet (UV) lithography technology and measured by a THz time-domain spectroscope (TDS) system. The resonant frequencies of the sensor are at 0.37 and 1.13 THz, with transmission rates of 2.9% and 0.3%, respectively. With an analyte layer attached to the sensor's surface, the sensitivity of refractive index sensing can be calculated as 0.09 and 0.28 THz/RIU (refractive index unit) at the two resonant frequencies. In order to validate the exceptional pesticide sensing performance of the sensor, chlorpyrifos-methyl acetone solutions with various concentrations are added on it. Furthermore, a monolayer of graphene is coated on the sensor's surface, which is proved capable of improving pesticide sensing sensitivity at low concentrations due to strong π-π stacking interactions with π-electrons in chlorpyrifos-methyl solutions. Therefore, the graphene-coated sensor can be utilized in detecting pesticide solutions with low concentrations, and the sensor without graphene is preferred for high concentration detection. This work provides a novel option for the THz metamaterial sensor with high sensitivity covering a wide pesticide concentration range.
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Tumor hypoxia, high oxidative stress, and low immunogenic create a deep-rooted immunosuppressive microenvironment, posing a major challenge to the therapeutic efficiency of cancer immunotherapy for solid tumor. Herein, an intelligent nanoplatform responsive to the tumor microenvironment (TME) capable of hypoxia relief and immune stimulation has been engineered for efficient solid tumor immunotherapy. The MnO2@OxA@OMV nanoreactor, enclosing bacterial-derived outer membrane vesicles (OMVs)-wrapped MnO2 nanoenzyme and the immunogenic cell death inducer oxaliplatin (OxA), demonstrated intrinsic catalase-like activity within the TME, which effectively catalyzed the endogenous H2O2 into O2 to enable a prolonged oxygen supply, thereby alleviating the tumor's oxidative stress and hypoxic TME, and expediting OxA release. The combinational action of OxA-caused ICD effect and Mn2+ from nanoreactor enabled the motivation of the cGAS-STING pathway to significantly improve the activation of STING and dendritic cells (DCs) maturation, resulting in metalloimmunotherapy. Furthermore, the immunostimulant OMVs played a crucial role in promoting the infiltration of activated CD8+T cells into the solid tumor. Overall, the nanoreactor offers a robust platform for solid tumor treatment, highlighting the significant potential of combining relief from tumor hypoxia and immune stimulation for metalloimmunotherapy. STATEMENT OF SIGNIFICANCE: A tailor-made nanoreactor was fabricated by enclosing bacterial-derived outer membrane vesicles (OMVs) onto MnO2 nanoenzyme and loading with immunogenic cell death inducer oxaliplatin (OxA) for tumor metalloimmunotherapy. The nanoreactor possesses intrinsic catalase-like activity within the tumor microenvironment, which effectively enabled a prolonged oxygen supply by catalyzing the conversion of endogenous H2O2 into O2, thereby alleviating tumor hypoxia and expediting OxA release. Furthermore, the TME-responsive release of nutritional Mn2+ sensitized the cGAS-STING pathway and collaborated with OxA-induced immunogenic cell death (ICD). Combing with immunostimulatory OMVs enhances the uptake of nanoreactors by DCs and promotes the infiltration of activated CD8+T cells. This nanoreactor offers a robust platform for solid tumor treatment, highlighting the significant potential of combining relief from tumor hypoxia and immune stimulation for metalloimmunotherapy.
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Inmunoterapia , Microambiente Tumoral , Animales , Inmunoterapia/métodos , Ratones , Microambiente Tumoral/efectos de los fármacos , Línea Celular Tumoral , Hipoxia Tumoral/efectos de los fármacos , Compuestos de Manganeso/química , Compuestos de Manganeso/farmacología , Oxaliplatino/farmacología , Oxaliplatino/química , Óxidos/química , Óxidos/farmacología , Manganeso/química , Manganeso/farmacología , Humanos , Femenino , Neoplasias/terapia , Neoplasias/patología , Neoplasias/inmunología , Neoplasias/tratamiento farmacológico , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Células Dendríticas/inmunología , Ratones Endogámicos C57BLRESUMEN
Multimodal /components tumors synergistic therapy is a crucial approach for enhancing comprehensive efficacy. Our research has identified lots of high efficiency synergies among four suitable components, revealing combinations with remarkably low combination index (CI) values (10-3-10-8). These combinations hold promise for large tumor powerful electrothermal-thermodynamic-multi-chemo trimodal therapy. To implement this approach, we developed four-component of double-layer infinite coordination polymer (ICP) nanocomposites, in which hypoxia-activated AQ4N and thermodynamic agent AIPH coordinated with Cu(â ¡) to form initial layer of positively charged ICPs-l NPs, chemotherapeutic agents gossypol-hyaluronic acid (G-HA) and CA4 coordinated with Fe(â ¢) to form out layer of negatively charged ICPs-2 NPs, then double-layer infinite coordination polymer nanocomposites (ICPs-1@ICPs-2 CNPs) were fabricated by electrostatic adsorption using ICPs-l NPs and ICPs-2 NPs. Cell experiments have extensively optimized the coordination combinations of the four components and the composition of the two layers. A programmable three-stage therapeutic procedure, assisted by a micro-electrothermal needle (MEN), was developed. Under this procedure the resulting nanocomposites demonstrate the powerful trimodal comprehensive therapeutic outcomes for large tumors using lower components dosage, achieving a tumor inhibition rate nearly reaching 100 % and no recurrence for 60 days. This study offers remarkable potential for tumor multimodal /components synergistic therapy in future.
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Antineoplásicos , Nanocompuestos , Polímeros , Nanocompuestos/química , Polímeros/química , Antineoplásicos/química , Antineoplásicos/farmacología , Humanos , Animales , Ratones , Ácido Hialurónico/química , Propiedades de Superficie , Tamaño de la Partícula , Ensayos de Selección de Medicamentos Antitumorales , Supervivencia Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Neoplasias/terapiaRESUMEN
Gaseous signaling molecules (GSMs) including nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H2S) have presented excellent therapeutic efficacy such as anti-inflammatory, anti-microbial and anti-cancer effects and multiple biomedical applications in recent years. As the three most vital signaling molecules in human physiology, these three GSMs show so intertwined and orchestrated interactions that the synergy of multiple gases may demonstrate a more complex therapeutic potential than single gas delivery. Consequently, researchers have been devoted to developing codelivery systems of GSMs by synthesizing a single molecule as a dual donor to maximize the gaseous therapeutic efficacy. In this minireview, we summarize the recent developments of molecules or materials enabling codelivery of GSMs for biomedical applications. It appears that compared with the abundant cases of codelivery of NO and H2S, research on codelivery of CO and the other two GSMs separately remains to be explored.
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Monóxido de Carbono , Sulfuro de Hidrógeno , Óxido Nítrico , Monóxido de Carbono/química , Humanos , Sulfuro de Hidrógeno/química , Sulfuro de Hidrógeno/metabolismo , Óxido Nítrico/química , Óxido Nítrico/metabolismo , Gases/química , Animales , Gasotransmisores/metabolismo , Gasotransmisores/químicaRESUMEN
Colon cancer ranks among the most prevalent malignancies worldwide, trailing only lung and breast cancer in incidence. Despite the availability of numerous therapeutic strategies, the burden of new cases and fatalities remains high in countries undergoing socioeconomic transitions. Natural products offer promising avenues for developing more effective and less toxic anticancer agents, expanding the clinical arsenal. In this investigation, we isolated a triterpenoid, (21â¯S,23â¯R,24â¯R)-21,23-epoxy-24-hydroxy-21-methoxytirucalla-7,25-dien-3-one (EHMT), from the fruits of Melia azedarach L., which exhibited significant inhibitory activity against colon cancer cells while sparing normal cells. EHMT effectively curtailed colony formation and induced apoptosis and cell cycle arrest in the HCT116 cell line. Furthermore, EHMT prompted the generation of reactive oxygen species (ROS) and the depolarization of mitochondrial membrane potential. Notably, EHMT treatment triggered ROS-mediated cell apoptosis via activation of the JNK signaling pathway in HCT116 cells. Additionally, our findings extended to Caenorhabditis elegans, where EHMT induced ROS accumulation and apoptosis. Collectively, these findings position EHMT as a promising candidate for the development of anticancer agents in the treatment of colon cancer, offering new hope in the battle against this formidable disease.
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Apoptosis , Caenorhabditis elegans , Proliferación Celular , Neoplasias del Colon , Sistema de Señalización de MAP Quinasas , Especies Reactivas de Oxígeno , Triterpenos , Humanos , Apoptosis/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Animales , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Neoplasias del Colon/metabolismo , Triterpenos/farmacología , Proliferación Celular/efectos de los fármacos , Células HCT116 , Caenorhabditis elegans/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacosRESUMEN
Introduction: Mossy biocrust represents a stable stage in the succession of biological soil crust in arid and semi-arid areas, providing a microhabitat that maintains microbial diversity. However, the impact of mossy biocrust rhizoid soil and different particle sizes within the mossy biocrust layer and sublayer on microbial diversity and soil enzyme activities remains unclear. Methods: This study utilized Illumina MiSeq sequencing and high-throughput fluorometric technique to assess the differences in microbial diversity and soil extracellular enzymes between mossy biocrust rhizoid soil and different particle sizes within the mossy biocrust sifting and sublayer soil. Results: The results revealed that the total organic carbon (TOC), total nitrogen (TN), ammonium (NH4+) and nitrate (NO3-) in mossy biocrust rhizoid soil were the highest, with significantly higher TOC, TN, and total phosphorus (TP) in mossy biocrust sifting soil than those in mossy biocrust sublayer soil. Extracellular enzyme activities (EAAs) exhibited different responses to various soil particle sizes in mossy biocrust. Biocrust rhizoid soil (BRS) showed higher C-degrading enzyme activity and lower P-degrading enzyme activity, leading to a significant increase in enzyme C: P and N: P ratios. Mossy biocrust soils were all limited by microbial relative nitrogen while pronounced relative nitrogen limitation and microbial maximum relative carbon limitation in BRS. The diversity and richness of the bacterial community in the 0.2 mm mossy biocrust soil (BSS0.2) were notably lower than those in mossy biocrust sublayer, whereas the diversity and richness of the fungal community in the rhizoid soil were significantly higher than those in mossy biocrust sublayer. The predominant bacterial phyla in mossy biocrust were Actinobacteriota, Protebacteria, Chloroflexi, and Acidobacteriota, whereas in BSS0.2, the predominant bacterial phyla were Actinobacteriota, Protebacteria, and Cyanobacteria. Ascomycota and Basidiomycota were dominant phyla in mossy biocrust. The bacterial and fungal community species composition exhibited significant differences. The mean proportions of Actinobacteriota, Protebacteria, Chloroflexi, Acidobacteriota, Acidobacteria, Cyanobacteria, and Bacteroidota varied significantly between mossy biocrust rhizoid and different particle sizes of mossy biocrust sifting and sublayer soil (p < 0.05). Similarly, significant differences (p < 0.05) were observed in the mean proportions of Ascomycota, Basidiomycota, and Glomeromycota between mossy biocrust rhizoid and different particle sizes within the mossy biocrust sifting and sublayer soil. The complexity and connectivity of bacterial and fungal networks were higher in mossy biocrust rhizoid soil compared with different particle sizes within the mossy biocrust sifting and sublayer soil. Discussion: These results offer valuable insights to enhance our understanding of the involvement of mossy biocrust in the biogeochemical cycle of desert ecosystems.
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The regeneration and upgrading of spent LiFePO4 cathodes (S-LFP) were achieved via a one-step hydrothermal treatment. The reducing effect of phytic acid could restore the degraded structure associated with an aqueous Li source. Meanwhile, Li ions are easily chelated by phytic acid groups, and a Li3PO4 coating layer could be formed to reconstruct the surface of the LFP. The regenerated LFP exhibits faster reaction kinetics, larger high-rate charge/discharge capacity, and better cycling performance than commercial LFPs, suggesting that our proposed strategy is a promising technology for the recovery of spent cathode materials.
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Uncertainties in the relative biological effectiveness (RBE) of proton remains a major barrier to the biological optimization of proton therapy. A large amount of experimental data suggest that proton RBE is variable. As an evolving Monte Carlo code toolkit, Geant4-DNA is able to simulate the initial DNA damage caused by particle beams through physical and chemical interactions at the nanometer scale over a short period of time. This contributes to evaluating the radiobiological effects induced by ionizing radiation. Based on the Geant4-DNA toolkit, this study constructed a DNA geometric model containing 6.32Gbp, simulated the relationship between radiochemical yields (G-values) and their corresponding chemical constructors, and calculated a detailed calculation of the sources of damage and the complexity of damage in DNA strand breaks. The damage model constructed in this study can simulate the relative biological effectiveness (RBE) in the proton Bragg peak region. The results indicate that: (1) When the electron energy is below 400 keV, the yield of OH·account for 18.1% to 25.3% of the total water radiolysis yields. (2) Under the influence of histone clearance function, the yield of indirect damage account for over 72.93% of the yield of DNA strand breaks (SBs). When linear energy transfer (LET) increased from 29.79 (keV/µm) to 64.29 (keV/µm), the yield of double strand breaks (DSB) increased from 17.27% to 32.65%. (3) By investigating the effect of proton Bragg peak depth on the yield of direct DSB (DSBdirect) and total DSB (DSBtotal), theRBEDSBtotandRBEDSBdirlevels of cells show that the RBE value of protons reaches 2.2 in the Bragg peak region.
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Terapia de Protones , Protones , Efectividad Biológica Relativa , Roturas del ADN de Doble Cadena , ADNRESUMEN
The CRISPR/Cas13a system has promising applications in clinical small noncoding RNA (sncRNA) detection because it is free from the interference of genomic DNA. However, detecting ultrashort sncRNAs (less than 20 nucleotides) has been challenging because the Cas13a nuclease requires longer crRNA-target RNA hybrids to be activated. Here, we report the development of a foldback-crRNA-enhanced CRISPR/Cas13a (FCECas13a) system that overcomes the limitations of the current CRISPR/Cas13a system in detecting ultrashort sncRNAs. The FCECas13a system employs a 3'-terminal foldback crRNA that hybridizes with the target ultrashort sncRNA, forming a double strand that "tricks" the Cas13a nuclease into activating the HEPN structural domain and generating trans-cleavage activity. The FCECas13a system can accurately detect miRNA720 (a sncRNA currently known as tRNA-derived small RNA), which is only 17 nucleotides long and has a concentration as low as 15 fM within 20 min. This FCECas13a system opens new avenues for ultrashort sncRNA detection with significant implications for basic biological research, disease prognosis, and molecular diagnosis.
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Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , ARN Pequeño no Traducido , ARN Guía de Sistemas CRISPR-Cas , Sistemas CRISPR-Cas/genética , Endonucleasas/metabolismo , NucleótidosRESUMEN
The recovery of spent lithium-ion batteries and the treatment of phenol wastewater are both environmental and social issues. In this study, the enhanced recovery of spent lithium-ion batteries and the efficient treatment of phenol wastewater are smartly coupled via a "treating waste with waste" strategy. Under optimal conditions, the leaching process involving phenol achieves 98% and 96% efficiency for Co and Li, respectively. After precipitation, Co and Li could be recovered as Co(OH)2 and Li2CO3, and the precipitated Co(OH)2 was further calcined to generate Co3O4. Furthermore, the organic contaminants that remained in the waste-leaching solution could be removed by a spent graphite-activating peroxymonosulfate (PMS) process. It is noteworthy that the total organic carbon (TOC) in the waste-leaching solution could be removed using fewer PMS compared with the original phenol wastewater owing to the pre-oxidation of phenol during the leaching process, further confirming the advantage of this "treating waste with waste" strategy.
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Litio , Metales , Aguas Residuales , Fenol , Reciclaje , Fenoles , Suministros de Energía EléctricaRESUMEN
We report the development of a self-renewable tag (srTAG) for protein fluorescence imaging. srTAG leverages the "on-protein" fluorophore equilibrium between the fluorescent zwitterion and non-fluorescent spirocyclic form and the reversible fluorescence labeling to enable self-recovery of fluorescence after photobleaching. This small-sized srTAG allows 2-6 times longer imaging duration compared to other commonly used self-labeling tags and is compatible with fluorophores with different spectral properties. This study provides a new strategy for fine tuning of self-labeling tags.