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1.
Nature ; 626(7997): 72-78, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38297173

RESUMEN

Recent breakthroughs in fibre technology have enabled the assembly of functional materials with intimate interfaces into a single fibre with specific geometries1-11, delivering diverse functionalities over a large area, for example, serving as sensors, actuators, energy harvesting and storage, display, and healthcare apparatus12-17. As semiconductors are the critical component that governs device performance, the selection, control and engineering of semiconductors inside fibres are the key pathways to enabling high-performance functional fibres. However, owing to stress development and capillary instability in the high-yield fibre thermal drawing, both cracks and deformations in the semiconductor cores considerably affect the performance of these fibres. Here we report a mechanical design to achieve ultralong, fracture-free and perturbation-free semiconductor fibres, guided by a study on stress development and capillary instability at three stages of the fibre formation: the viscous flow, the core crystallization and the subsequent cooling stage. Then, the exposed semiconductor wires can be integrated into a single flexible fibre with well-defined interfaces with metal electrodes, thereby achieving optoelectronic fibres and large-scale optoelectronic fabrics. This work provides fundamental insights into extreme mechanics and fluid dynamics with geometries that are inaccessible in traditional platforms, essentially addressing the increasing demand for flexible and wearable optoelectronics.

2.
Nature ; 624(7992): 579-585, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38057667

RESUMEN

The transfer of photosynthetically produced organic carbon from surface to mesopelagic waters draws carbon dioxide from the atmosphere1. However, current observation-based estimates disagree on the strength of this biological carbon pump (BCP)2. Earth system models (ESMs) also exhibit a large spread of BCP estimates, indicating limited representations of the known carbon export pathways3. Here we use several decades of hydrographic observations to produce a top-down estimate of the strength of the BCP with an inverse biogeochemical model that implicitly accounts for all known export pathways. Our estimate of total organic carbon (TOC) export at 73.4 m (model euphotic zone depth) is 15.00 ± 1.12 Pg C year-1, with only two-thirds reaching 100 m depth owing to rapid remineralization of organic matter in the upper water column. Partitioned by sequestration time below the euphotic zone, τ, the globally integrated organic carbon production rate with τ > 3 months is 11.09 ± 1.02 Pg C year-1, dropping to 8.25 ± 0.30 Pg C year-1 for τ > 1 year, with 81% contributed by the non-advective-diffusive vertical flux owing to sinking particles and vertically migrating zooplankton. Nevertheless, export of organic carbon by mixing and other fluid transport of dissolved matter and suspended particles remains regionally important for meeting the respiratory carbon demand. Furthermore, the temperature dependence of the sequestration efficiency inferred from our inversion suggests that future global warming may intensify the recycling of organic matter in the upper ocean, potentially weakening the BCP.


Asunto(s)
Dióxido de Carbono , Agua de Mar , Agua , Animales , Dióxido de Carbono/metabolismo , Fotosíntesis , Agua de Mar/química , Agua/química , Agua/metabolismo , Zooplancton/metabolismo , Calentamiento Global , Océanos y Mares
3.
Nature ; 604(7904): 72-79, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35388196

RESUMEN

Covalent organic frameworks (COFs) are distinguished from other organic polymers by their crystallinity1-3, but it remains challenging to obtain robust, highly crystalline COFs because the framework-forming reactions are poorly reversible4,5. More reversible chemistry can improve crystallinity6-9, but this typically yields COFs with poor physicochemical stability and limited application scope5. Here we report a general and scalable protocol to prepare robust, highly crystalline imine COFs, based on an unexpected framework reconstruction. In contrast to standard approaches in which monomers are initially randomly aligned, our method involves the pre-organization of monomers using a reversible and removable covalent tether, followed by confined polymerization. This reconstruction route produces reconstructed COFs with greatly enhanced crystallinity and much higher porosity by means of a simple vacuum-free synthetic procedure. The increased crystallinity in the reconstructed COFs improves charge carrier transport, leading to sacrificial photocatalytic hydrogen evolution rates of up to 27.98 mmol h-1 g-1. This nanoconfinement-assisted reconstruction strategy is a step towards programming function in organic materials through atomistic structural control.

4.
Cell ; 149(5): 1098-111, 2012 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-22632973

RESUMEN

Akt kinase plays a central role in cell growth, metabolism, and tumorigenesis. The TRAF6 E3 ligase orchestrates IGF-1-mediated Akt ubiquitination and activation. Here, we show that Akt ubiquitination is also induced by activation of ErbB receptors; unexpectedly, and in contrast to IGF-1 induced activation, the Skp2 SCF complex, not TRAF6, is a critical E3 ligase for ErbB-receptor-mediated Akt ubiquitination and membrane recruitment in response to EGF. Skp2 deficiency impairs Akt activation, Glut1 expression, glucose uptake and glycolysis, and breast cancer progression in various tumor models. Moreover, Skp2 overexpression correlates with Akt activation and breast cancer metastasis and serves as a marker for poor prognosis in Her2-positive patients. Finally, Skp2 silencing sensitizes Her2-overexpressing tumors to Herceptin treatment. Our study suggests that distinct E3 ligases are utilized by diverse growth factors for Akt activation and that targeting glycolysis sensitizes Her2-positive tumors to Herceptin treatment.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Transformación Celular Neoplásica , Proteínas F-Box/metabolismo , Glucólisis , Proteínas Quinasas Asociadas a Fase-S/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Animales , Neoplasias de la Mama/metabolismo , Modelos Animales de Enfermedad , Resistencia a Antineoplásicos , Femenino , Humanos , Ratones , Receptor ErbB-2/metabolismo , Proteínas Quinasas Asociadas a Fase-S/genética , Trastuzumab , Ubiquitinación
5.
Cell ; 150(3): 575-89, 2012 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-22863010

RESUMEN

The mechanism by which cells decide to skip mitosis to become polyploid is largely undefined. Here we used a high-content image-based screen to identify small-molecule probes that induce polyploidization of megakaryocytic leukemia cells and serve as perturbagens to help understand this process. Our study implicates five networks of kinases that regulate the switch to polyploidy. Moreover, we find that dimethylfasudil (diMF, H-1152P) selectively increased polyploidization, mature cell-surface marker expression, and apoptosis of malignant megakaryocytes. An integrated target identification approach employing proteomic and shRNA screening revealed that a major target of diMF is Aurora kinase A (AURKA). We further find that MLN8237 (Alisertib), a selective inhibitor of AURKA, induced polyploidization and expression of mature megakaryocyte markers in acute megakaryocytic leukemia (AMKL) blasts and displayed potent anti-AMKL activity in vivo. Our findings provide a rationale to support clinical trials of MLN8237 and other inducers of polyploidization and differentiation in AMKL.


Asunto(s)
Azepinas/farmacología , Descubrimiento de Drogas , Leucemia Megacarioblástica Aguda/tratamiento farmacológico , Megacariocitos/metabolismo , Poliploidía , Pirimidinas/farmacología , Bibliotecas de Moléculas Pequeñas , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , Animales , Aurora Quinasa A , Aurora Quinasas , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Humanos , Leucemia Megacarioblástica Aguda/genética , Megacariocitos/citología , Megacariocitos/patología , Ratones , Ratones Endogámicos C57BL , Mapas de Interacción de Proteínas , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Quinasas Asociadas a rho/metabolismo
6.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38493343

RESUMEN

Recent advancements in single-cell sequencing technologies have generated extensive omics data in various modalities and revolutionized cell research, especially in the single-cell RNA and ATAC data. The joint analysis across scRNA-seq data and scATAC-seq data has paved the way to comprehending the cellular heterogeneity and complex cellular regulatory networks. Multi-omics integration is gaining attention as an important step in joint analysis, and the number of computational tools in this field is growing rapidly. In this paper, we benchmarked 12 multi-omics integration methods on three integration tasks via qualitative visualization and quantitative metrics, considering six main aspects that matter in multi-omics data analysis. Overall, we found that different methods have their own advantages on different aspects, while some methods outperformed other methods in most aspects. We therefore provided guidelines for selecting appropriate methods for specific scenarios and tasks to help obtain meaningful insights from multi-omics data integration.


Asunto(s)
Benchmarking , Multiómica , Algoritmos , Ciclo Celular , ARN
7.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38324621

RESUMEN

Single-cell clustered regularly interspaced short palindromic repeats-sequencing (scCRISPR-seq) is an emerging high-throughput CRISPR screening technology where the true cellular response to perturbation is coupled with infected proportion bias of guide RNAs (gRNAs) across different cell clusters. The mixing of these effects introduces noise into scCRISPR-seq data analysis and thus obstacles to relevant studies. We developed scDecouple to decouple true cellular response of perturbation from the influence of infected proportion bias. scDecouple first models the distribution of gene expression profiles in perturbed cells and then iteratively finds the maximum likelihood of cell cluster proportions as well as the cellular response for each gRNA. We demonstrated its performance in a series of simulation experiments. By applying scDecouple to real scCRISPR-seq data, we found that scDecouple enhances the identification of biologically perturbation-related genes. scDecouple can benefit scCRISPR-seq data analysis, especially in the case of heterogeneous samples or complex gRNA libraries.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento , ARN Guía de Sistemas CRISPR-Cas
8.
Proc Natl Acad Sci U S A ; 120(15): e2216698120, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-37023129

RESUMEN

Discovering DNA regulatory sequence motifs and their relative positions is vital to understanding the mechanisms of gene expression regulation. Although deep convolutional neural networks (CNNs) have achieved great success in predicting cis-regulatory elements, the discovery of motifs and their combinatorial patterns from these CNN models has remained difficult. We show that the main difficulty is due to the problem of multifaceted neurons which respond to multiple types of sequence patterns. Since existing interpretation methods were mainly designed to visualize the class of sequences that can activate the neuron, the resulting visualization will correspond to a mixture of patterns. Such a mixture is usually difficult to interpret without resolving the mixed patterns. We propose the NeuronMotif algorithm to interpret such neurons. Given any convolutional neuron (CN) in the network, NeuronMotif first generates a large sample of sequences capable of activating the CN, which typically consists of a mixture of patterns. Then, the sequences are "demixed" in a layer-wise manner by backward clustering of the feature maps of the involved convolutional layers. NeuronMotif can output the sequence motifs, and the syntax rules governing their combinations are depicted by position weight matrices organized in tree structures. Compared to existing methods, the motifs found by NeuronMotif have more matches to known motifs in the JASPAR database. The higher-order patterns uncovered for deep CNs are supported by the literature and ATAC-seq footprinting. Overall, NeuronMotif enables the deciphering of cis-regulatory codes from deep CNs and enhances the utility of CNN in genome interpretation.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Motivos de Nucleótidos/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Bases de Datos Factuales
9.
Proc Natl Acad Sci U S A ; 120(37): e2305572120, 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37669368

RESUMEN

One essential element of redox flow batteries (RFBs) is the flow field. Certain dead zones that cause local overpotentials and side effects are present in all conventional designs. To lessen the detrimental effects, a dead-zone-compensated design of flow field optimization is proposed. The proposed architecture allows for the detection of dead zones and their compensation on existing flow fields. Higher reactant concentrations and uniformity factors can be revealed in the 3D multiphysical simulation. The experiments also demonstrate that at an energy efficiency (EE) of 80%, the maximum current density of the novel flow field is 205 mA cm-2, which is much higher than the values for the previous ones (165 mA cm-2) and typical serpentine flow field (153 mA cm-2). Extensions of the design have successfully increased system EE (2.7 to 4.3%) for a variety of flow patterns. As a result, the proposed design is demonstrated to be a general method to support the functionality and application of RFBs.

10.
Brief Bioinform ; 24(6)2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37824741

RESUMEN

Cell-cell communication events (CEs) are mediated by multiple ligand-receptor (LR) pairs. Usually only a particular subset of CEs directly works for a specific downstream response in a particular microenvironment. We name them as functional communication events (FCEs) of the target responses. Decoding FCE-target gene relations is: important for understanding the mechanisms of many biological processes, but has been intractable due to the mixing of multiple factors and the lack of direct observations. We developed a method HoloNet for decoding FCEs using spatial transcriptomic data by integrating LR pairs, cell-type spatial distribution and downstream gene expression into a deep learning model. We modeled CEs as a multi-view network, developed an attention-based graph learning method to train the model for generating target gene expression with the CE networks, and decoded the FCEs for specific downstream genes by interpreting trained models. We applied HoloNet on three Visium datasets of breast cancer and liver cancer. The results detangled the multiple factors of FCEs by revealing how LR signals and cell types affect specific biological processes, and specified FCE-induced effects in each single cell. We conducted simulation experiments and showed that HoloNet is more reliable on LR prioritization in comparison with existing methods. HoloNet is a powerful tool to illustrate cell-cell communication landscapes and reveal vital FCEs that shape cellular phenotypes. HoloNet is available as a Python package at https://github.com/lhc17/HoloNet.


Asunto(s)
Neoplasias Hepáticas , Transcriptoma , Humanos , Perfilación de la Expresión Génica , Comunicación Celular/genética , Simulación por Computador , Microambiente Tumoral
11.
Nature ; 566(7743): 205-211, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30760914

RESUMEN

Uncertainty in the global patterns of marine nitrogen fixation limits our understanding of the response of the ocean's nitrogen and carbon cycles to environmental change. The geographical distribution of and ecological controls on nitrogen fixation are difficult to constrain with limited in situ measurements. Here we present convergent estimates of nitrogen fixation from an inverse biogeochemical and a prognostic ocean model. Our results demonstrate strong spatial variability in the nitrogen-to-phosphorus ratio of exported organic matter that greatly increases the global nitrogen-fixation rate (because phytoplankton manage with less phosphorus when it is in short supply). We find that the input of newly fixed nitrogen from microbial fixation and external inputs (atmospheric deposition and river fluxes) accounts for up to 50 per cent of carbon export in subtropical gyres. We also find that nitrogen fixation and denitrification are spatially decoupled but that nevertheless nitrogen sources and sinks appear to be balanced over the past few decades. Moreover, we propose a role for top-down zooplankton grazing control in shaping the global patterns of nitrogen fixation. Our findings suggest that biological carbon export in the ocean is higher than expected and that stabilizing nitrogen-cycle feedbacks are weaker than previously thought.


Asunto(s)
Organismos Acuáticos/metabolismo , Fijación del Nitrógeno , Nitrógeno/metabolismo , Fitoplancton/metabolismo , Zooplancton/metabolismo , Animales , Organismos Acuáticos/química , Atmósfera/química , Carbono/metabolismo , Secuestro de Carbono , Retroalimentación , Mapeo Geográfico , Nitrógeno/análisis , Océanos y Mares , Fósforo/análisis , Fósforo/metabolismo , Fitoplancton/química , Ríos/química , Zooplancton/química
12.
Nano Lett ; 24(23): 7040-7047, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38804573

RESUMEN

Flexible pressure sensors with a broad range and high sensitivity are greatly desired yet challenging to build. Herein, we have successfully fabricated a pressure-temperature dual sensor via an ionic assisted charge enhancement strategy. Benefiting from the immobilization effect for [EMIM+] [TFSI-] ion pairs and charge transfer between ionic liquid (IL) and HFMO (H10Fe3Mo21O51), the formed IL-HFMO-TPU pressure sensor shows a high sensitivity of 25.35 kPa-1 and broad sensing range (∼10 MPa), respectively. Furthermore, the sensor device exhibits high durability and stability (5000 cycles@1 MPa). The IL-HFMO-TPU sensor also shows the merit of good temperature sensing properties. Attributed to these superior properties, the proposed sensor device could detect pressure in an ultrawide sensing range (from Pa to MPa), including breathe and biophysical signal monitoring etc. The proposed ionic assisted enhancement approach is a generic strategy for constructing high performance flexible pressure-temperature dual sensor.

13.
J Am Chem Soc ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842422

RESUMEN

Photocatalytic covalent organic frameworks (COFs) are typically constructed with rigid aromatic linkers for crystallinity and extended π-conjugation. However, the essential hydrophobicity of the aromatic backbone can limit their performances in water-based photocatalytic reactions. Here, we for the first time report the synthesis of hydrophilic COFs with aliphatic linkers [tartaric acid dihydrazide (TAH) and butanedioic acid dihydrazide] that can function as efficient photocatalysts for H2O2 and H2 evolution. In these hydrophilic aliphatic linkers, the specific multiple hydrogen bonding networks not only enhance crystallization but also ensure an ideal compatibility of crystallinity, hydrophilicity, and light harvesting. The resulting aliphatic linker COFs adopt an unusual ABC stacking, giving rise to approximately 0.6 nm nanopores with an improved interaction with water guests. Remarkably, both aliphatic linker-based COFs show strong visible light absorption, along with a narrow optical band gap of ∼1.9 eV. The H2O2 evolution rate for TAH-COF reaches up to 6003 µmol h-1 g-1, in the absence of sacrificial agents, surpassing the performance of all previously reported COF-based photocatalysts. Theoretical calculations reveal that the TAH linker can enhance the indirect two-electron oxygen reduction reaction for H2O2 production by improving the O2 adsorption and stabilizing the *OOH intermediate. This study opens a new avenue for constructing semiconducting COFs using nonaromatic linkers.

14.
Mol Pain ; 20: 17448069241239231, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38417838

RESUMEN

Cancer-induced bone pain (CIBP) is one of the most common and feared symptoms in patients with advanced tumors. The X-C motif chemokine ligand 12 (CXCL12) and the CXCR4 receptor have been associated with glial cell activation in bone cancer pain. Moreover, mitogen-activated protein kinases (MAPKs), as downstream CXCL12/CXCR4 signals, and c-Jun, as activator protein AP-1 components, contribute to the development of various types of pain. However, the specific CIBP mechanisms remain unknown. Esketamine is a non-selective N-methyl-d-aspartic acid receptor (NMDA) inhibitor commonly used as an analgesic in the clinic, but its analgesic mechanism in bone cancer pain remains unclear. We used a tumor cell implantation (TCI) model and explored that CXCL12/CXCR4, p-MAPKs, and p-c-Jun were stably up-regulated in the spinal cord. Immunofluorescence images showed activated microglia in the spinal cord on day 14 after TCI and co-expression of CXCL12/CXCR4, p-MAPKs (p-JNK, p-ERK, p-p38 MAPK), and p-c-Jun in microglia. Intrathecal injection of the CXCR4 inhibitor AMD3100 reduced JNK and c-Jun phosphorylations, and intrathecal injection of the JNK inhibitor SP600125 and esketamine also alleviated TCI-induced pain and reduced the expression of p-JNK and p-c-Jun in microglia. Overall, our data suggest that the CXCL12/CXCR4-JNK-c-Jun signaling pathway of microglia in the spinal cord mediates neuronal sensitization and pain hypersensitivity in cancer-induced bone pain and that esketamine exerts its analgesic effect by inhibiting the JNK-c-Jun pathway.


Asunto(s)
Neoplasias Óseas , Dolor en Cáncer , Ketamina , Humanos , Ratas , Animales , Dolor en Cáncer/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Ratas Sprague-Dawley , Dolor/metabolismo , Neoplasias Óseas/complicaciones , Médula Espinal/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Asta Dorsal de la Médula Espinal/metabolismo , Analgésicos/farmacología , Hiperalgesia/metabolismo
15.
Br J Cancer ; 130(5): 861-868, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38195887

RESUMEN

BACKGROUND: Multiple antigens, autoantibodies (AAb), and antigen-autoantibody (Ag-AAb) complexes were compared for their ability to complement CA125 for early detection of ovarian cancer. METHODS: Twenty six biomarkers were measured in a single panel of sera from women with early stage (I-II) ovarian cancers (n = 64), late stage (III-IV) ovarian cancers (186), benign pelvic masses (200) and from healthy controls (502), and then split randomly (50:50) into a training set to identify the most promising classifier and a validation set to compare its performance to CA125 alone. RESULTS: Eight biomarkers detected ≥ 8% of early stage cases at 98% specificity. A four-biomarker panel including CA125, HE4, HE4 Ag-AAb and osteopontin detected 75% of early stage cancers in the validation set from among healthy controls compared to 62% with CA125 alone (p = 0.003) at 98% specificity. The same panel increased sensitivity for distinguishing early-stage ovarian cancers from benign pelvic masses by 25% (p = 0.0004) at 95% specificity. From 21 autoantibody candidates, 3 AAb (anti-p53, anti-CTAG1 and annt-Il-8) detected 22% of early stage ovarian cancers, potentially lengthening lead time prior to diagnosis. CONCLUSION: A four biomarker panel achieved greater sensitivity at the same specificity for early detection of ovarian cancer than CA125 alone.


Asunto(s)
Autoanticuerpos , Neoplasias Ováricas , Femenino , Humanos , Sensibilidad y Especificidad , Curva ROC , Antígeno Ca-125 , Biomarcadores de Tumor , Neoplasias Ováricas/diagnóstico
16.
Genome Res ; 31(7): 1121-1135, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34140314

RESUMEN

Heterochromatin remodeling is critical for various cell processes. In particular, the "loss of heterochromatin" phenotype in cellular senescence is associated with the process of aging and age-related disorders. Although biological processes of senescent cells, including senescence-associated heterochromatin foci (SAHF) formation, chromosome compaction, and redistribution of key proteins, have been closely associated with high-order chromatin structure, the relationship between the high-order chromatin reorganization and the loss of heterochromatin phenotype during senescence has not been fully understood. By using senescent and deep senescent fibroblasts induced by DNA damage harboring the "loss of heterochromatin" phenotype, we observed progressive 3D reorganization of heterochromatin during senescence. Facultative and constitutive heterochromatin marked by H3K27me3 and H3K9me3, respectively, show different alterations. Facultative heterochromatin tends to switch from the repressive B-compartment to the active A-compartment, whereas constitutive heterochromatin shows no significant changes at the compartment level but enhanced interactions between themselves. Both types of heterochromatin show increased chromatin accessibility and gene expression leakage during senescence. Furthermore, increased chromatin accessibility in potential CTCF binding sites accompanies the establishment of novel loops in constitutive heterochromatin. Finally, we also observed aberrant expression of repetitive elements, including LTR (long terminal repeat) and satellite classes. Overall, facultative and constitutive heterochromatin show both similar and distinct multiscale alterations in the 3D map, chromatin accessibility, and gene expression leakage. This study provides an epigenomic map of heterochromatin reorganization during senescence.

17.
BMC Plant Biol ; 24(1): 23, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38166728

RESUMEN

BACKGROUND: Spiraea L. is a genus comprising approximately 90 species that are distributed throughout the northern temperate regions. China is recognized as the center of species diversity for this genus, hosting more than 70 species, including 47 endemic species. While Spiraea is well-known for its ornamental value, its taxonomic and phylogenetic studies have been insufficient. RESULTS: In this study, we conducted sequencing and assembly of the plastid genomes (plastomes) of 34 Asiatic Spiraea accessions (representing 27 Asiatic Spiraea species) from China and neighboring regions. The Spiraea plastid genome exhibits typical quadripartite structures and encodes 113-114 genes, including 78-79 protein-coding genes (PCGs), 30 tRNA genes, and 4 rRNA genes. Linear regression analysis revealed a significant correlation between genome size and the length of the SC region. By the sliding windows method, we identified several hypervariable hotspots within the Spiraea plastome, all of which were localized in the SC regions. Our phylogenomic analysis successfully established a robust phylogenetic framework for Spiraea, but it did not support the current defined section boundaries. Additionally, we discovered that the genus underwent diversification after the Early Oligocene (~ 30 Ma), followed by a rapid speciation process during the Pliocene and Pleistocene periods. CONCLUSIONS: The plastomes of Spiraea provided us invaluable insights into its phylogenetic relationships and evolutionary history. In conjunction with plastome data, further investigations utilizing other genomes, such as the nuclear genome, are urgently needed to enhance our understanding of the evolutionary history of this genus.


Asunto(s)
Genoma del Cloroplasto , Genoma de Plastidios , Rosaceae , Spiraea , Filogenia , Evolución Molecular , Genoma del Cloroplasto/genética
18.
Small ; 20(23): e2311272, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38366302

RESUMEN

Personal protective equipment pays attention exclusively to external safety protection and ignores the internal thermoregulation of physiological state in association with sweating. Herein, a super-hygroscopic calcium-doped poly(sodium 4-styrenesulfonate) and superhydrophobic metal-organic-framework-overlayed wearables (Ca-PSS/MOF) integrated cooling wearable is proposed for special personal thermal management (PTM). Compared to the pristine fabric, the superhydrophobic MOF wearables exhibit anti-fouling and antibacterial capabilities, and the antibacterial efficiency is up to 99.99% and 98.99% against E. coli and S. aureus, respectively. More importantly, Ca-PSS/MOF demonstrate significant heat index changes up to 25.5 °C by reducing relative humidity dramatically from 91.0% to 60.0% and temperature from 36.5 to 31.6 °C during the running test. The practical feasibility of the Ca-PSS/MOF cooling wearables is well proved with the protective suit of the fireman. Owing to these multifunctional merits, the sandwich-structured cooling Ca-PSS/MOF are expected to provide new insights for designing the next-generation multifunctional apparel for PTM.


Asunto(s)
Estructuras Metalorgánicas , Dispositivos Electrónicos Vestibles , Zinc , Zinc/química , Estructuras Metalorgánicas/química , Humanos , Escherichia coli , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/química , Antibacterianos/farmacología , Temperatura , Interacciones Hidrofóbicas e Hidrofílicas
19.
Small ; : e2312119, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38497515

RESUMEN

Anatase TiO2 as sodium-ion-battery anode has attracted increased attention because of its low volume change and good safety. However, low capacity and poor rate performance caused by low electrical conductivity and slow ion diffusion greatly impede its practical applications. Here, a bi-solvent enhanced pressure strategy that induces defects (oxygen vacancies) into TiO2 via N doping and reduces its size by using mutual-solvent ethanol and dopant dimethylformamide as pressure-increased reagent of tetrabutyl orthotitanate tetramer is proposed to fabricate N-doped TiO2 /C nanocomposites. The induced defects can increase ion storage sites, improve electrical conductivity, and decrease bandgap and ion diffuse energy barrier of TiO2 . The size reduction increases contact interfaces between TiO2 and C and shortens ion diffuse distance, thus increasing extra ion storage sites and boosting ion diffusion rate of TiO2 . The N-doped TiO2 possesses highly stable crystal structure with a slightly increase of 0.86% in crystal lattice spacing and 3.2% in particle size after fully sodiation. Consequently, as a sodium-ion battery anode, the nanocomposite delivers high capacity and superior rate capability along with ultralong cycling life. This work proposes a novel pressure-induced synthesis strategy that provides unique guidance for designing TiO2 -based anode materials with high capacity and excellent fast-charging capability.

20.
Biol Reprod ; 110(2): 408-418, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-37903059

RESUMEN

Non-obstructive azoospermia affects more than 10% of infertile men with over 70% patients are idiopathic with uncharacterized molecular mechanisms, which is referred as idiopathic non-obstructive azoospermia. In this study, we checked the morphology of Sertoli cell mitochondria in testis biopsies from patients with idiopathic non-obstructive azoospermia and patients with obstructive azoospermia who have normal spermiogenesis. The expression of 104 genes controlling mitochondria fission and fusion were analyzed in three gene expression datasets including a total of 60 patients with non-obstructive azoospermia. The levels of 7 candidate genes were detected in testis biopsies from 38 patients with idiopathic non-obstructive azoospermia and 24 patients with obstructive azoospermia who have normal spermatogenesis by RT-qPCR. Cell viability, apoptosis, mitochondria membrane potential, adenosine triphosphate production, oxygen consumption, and mitochondria morphology were examined in primary human Sertoli cells. Mouse spermatogonial stem cells were used to detect the cell supporting capacity of Sertoli cells. We observed that patients with idiopathic non-obstructive azoospermia had elongated mitochondria. MTFR2 and ATP5IF1 were downregulated, whereas BAK1 was upregulated in idiopathic non-obstructive azoospermia testis and Sertoli cells. Sertoli cells from patients with idiopathic non-obstructive azoospermia had reduced viability, mitochondria membrane potential, adenosine triphosphate production, oxygen consumption rate, glycolysis and increased apoptosis. Knockdown MTFR2 in Sertoli cells increased the mitochondria size. Knockdown ATP5IF1 did not change mitochondrial morphology but increased adenosine triphosphate hydrolysis. Overexpression of BAK1 reduced membrane potential and upregulated cell apoptosis. The dysregulation of all these three genes contributed to the dysfunction of Sertoli cells, which provides a clue for idiopathic non-obstructive azoospermia treatment.


Asunto(s)
Azoospermia , Enfermedades Mitocondriales , Masculino , Humanos , Ratones , Animales , Células de Sertoli/metabolismo , Azoospermia/genética , Dinámicas Mitocondriales , Testículo/metabolismo , Espermatogénesis/genética , Adenosina Trifosfato/metabolismo , Enfermedades Mitocondriales/metabolismo , Enfermedades Mitocondriales/patología , Proteína Destructora del Antagonista Homólogo bcl-2/genética , Proteína Destructora del Antagonista Homólogo bcl-2/metabolismo
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