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1.
Brief Bioinform ; 25(4)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38819253

RESUMEN

Spatially resolved transcriptomics (SRT) has emerged as a powerful tool for investigating gene expression in spatial contexts, providing insights into the molecular mechanisms underlying organ development and disease pathology. However, the expression sparsity poses a computational challenge to integrate other modalities (e.g. histological images and spatial locations) that are simultaneously captured in SRT datasets for spatial clustering and variation analyses. In this study, to meet such a challenge, we propose multi-modal domain adaption for spatial transcriptomics (stMDA), a novel multi-modal unsupervised domain adaptation method, which integrates gene expression and other modalities to reveal the spatial functional landscape. Specifically, stMDA first learns the modality-specific representations from spatial multi-modal data using multiple neural network architectures and then aligns the spatial distributions across modal representations to integrate these multi-modal representations, thus facilitating the integration of global and spatially local information and improving the consistency of clustering assignments. Our results demonstrate that stMDA outperforms existing methods in identifying spatial domains across diverse platforms and species. Furthermore, stMDA excels in identifying spatially variable genes with high prognostic potential in cancer tissues. In conclusion, stMDA as a new tool of multi-modal data integration provides a powerful and flexible framework for analyzing SRT datasets, thereby advancing our understanding of intricate biological systems.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Humanos , Perfilación de la Expresión Génica/métodos , Análisis por Conglomerados , Biología Computacional/métodos , Redes Neurales de la Computación , Neoplasias/genética , Algoritmos
2.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38324623

RESUMEN

Recent advances in spatially resolved transcriptomics (SRT) have brought ever-increasing opportunities to characterize expression landscape in the context of tissue spatiality. Nevertheless, there still exist multiple challenges to accurately detect spatial functional regions in tissue. Here, we present a novel contrastive learning framework, SPAtially Contrastive variational AutoEncoder (SpaCAE), which contrasts transcriptomic signals of each spot and its spatial neighbors to achieve fine-grained tissue structures detection. By employing a graph embedding variational autoencoder and incorporating a deep contrastive strategy, SpaCAE achieves a balance between spatial local information and global information of expression, enabling effective learning of representations with spatial constraints. Particularly, SpaCAE provides a graph deconvolutional decoder to address the smoothing effect of local spatial structure on expression's self-supervised learning, an aspect often overlooked by current graph neural networks. We demonstrated that SpaCAE could achieve effective performance on SRT data generated from multiple technologies for spatial domains identification and data denoising, making it a remarkable tool to obtain novel insights from SRT studies.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Redes Neurales de la Computación
3.
Nano Lett ; 24(18): 5403-5412, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38669639

RESUMEN

The efficacy of electrical stimulation facilitating peripheral nerve regeneration is evidenced extensively, while the associated secondary damage resulting from repeated electrode invasion and indiscriminate stimulation is inevitable. Here, we present an optogenetics strategy that utilizes upconversion nanoparticles (UCNPs) to convert deeply penetrating near-infrared excitation into blue emission, which activates an adeno-associated virus-encoding ChR2 photoresponsive ion channel on cell membranes. The induced Ca2+ flux, similar to the ion flux in the electrical stimulation approach, efficiently regulates viability and proliferation, secretion of nerve growth factor, and neural function of RSC96 cells. Furthermore, deep near-infrared excitation is harnessed to stimulate autologous Schwann cells in situ via a UCNP-composited scaffold, which enhances nerve sprouting and myelination, consequently promoting functional recovery, electrophysiological restoration, and reinnervation of damaged nerves. This developed postoperatively noninvasive optogenetics strategy presents a novel, minimally traumatic, and enduring therapeutic stimulus to effectively promote peripheral nerve repair.


Asunto(s)
Nanopartículas , Regeneración Nerviosa , Optogenética , Células de Schwann , Nervio Ciático , Animales , Optogenética/métodos , Nanopartículas/química , Ratas , Dependovirus/genética , Línea Celular , Traumatismos de los Nervios Periféricos/terapia
4.
BMC Plant Biol ; 24(1): 705, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39054416

RESUMEN

BACKGROUND: Drought stress limits significantly the crop productivity. However, plants have evolved various strategies to cope with the drought conditions by adopting complex molecular, biochemical, and physiological mechanisms. Members of the nuclear factor Y (NF-Y) transcription factor (TF) family constitute one of the largest TF classes and are involved in plant responses to abiotic stresses. RESULTS: TaNF-YB2, a NY-YB subfamily gene in T. aestivum, was characterized in this study focusing on its role in mediating plant adaptation to drought stress. Yeast two-hybrid (Y-2 H), biomolecular fluoresence complementation (BiFC), and Co-immunoprecipitation (Co-IP) assays indicated that TaNF-YB2 interacts with the NF-YA member TaNF-YA7 and NF-YC family member TaNF-YC7, which constitutes a heterotrimer TaNF-YB2/TaNF-YA7/TaNF-YC7. The TaNF-YB2 transcripts are induced in roots and aerial tissues upon drought signaling; GUS histochemical staining analysis demonstrated the roles of cis-regulatory elements ABRE and MYB situated in TaNF-YB2 promoter to contribute to target gene response to drought. Transgene analysis on TaNF-YB2 confirmed its functions in regulating drought adaptation via modulating stomata movement, osmolyte biosynthesis, and reactive oxygen species (ROS) homeostasis. TaNF-YB2 possessed the abilities in transcriptionally activating TaP5CS2, the P5CS family gene involving proline biosynthesis and TaSOD1, TaCAT5, and TaPOD5, the genes encoding antioxidant enzymes. Positive correlations were found between yield and the TaNF-YB2 transcripts in a core panel constituting 45 wheat cultivars under drought condition, in which two types of major haplotypes including TaNF-YB2-Hap1 and -Hap2 were included, with the former conferring more TaNF-YB2 transcripts and stronger plant drought tolerance. CONCLUSIONS: TaNF-YB2 is transcriptional response to drought stress. It is an essential regulator in mediating plant drought adaptation by modulating the physiological processes associated with stomatal movement, osmolyte biosynthesis, and reactive oxygen species (ROS) homeostasis, depending on its role in transcriptionally regulating stress response genes. Our research deepens the understanding of plant drought stress underlying NF-Y TF family and provides gene resource in efforts for molecular breeding the drought-tolerant cultivars in T. aestivum.


Asunto(s)
Sequías , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Factores de Transcripción , Triticum , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Triticum/genética , Triticum/fisiología , Triticum/metabolismo , Estrés Fisiológico/genética , Adaptación Fisiológica/genética , Genes de Plantas , Resistencia a la Sequía
5.
Small ; 20(28): e2308032, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38801010

RESUMEN

Low solar energy utilization efficiency and serious charge recombination remain major challenges for photocatalytic systems. Herein, a hollow core-shell Au/g-C3N4@Ag3PO4 photothermal nanoreactor is successfully prepared by a two-step deposition method. Benefit from efficient spectral utilization and fast charge separation induced by the unique hollow core-shell heterostructure, the H2 evolution rate of Au/g-C3N4@Ag3PO4 is 16.9 times that of the pristine g-C3N4, and the degradation efficiency of tetracycline is increased by 88.1%. The enhanced catalytic performance can be attributed to the ordered charge movement on the hollow core-shell structure and a local high-temperature environment, which effectively accelerates the carrier separation and chemical reaction kinetics. This work highlights the important role of the space confinement effect in photothermal catalysis and provides a promising strategy for the development of the next generation of highly efficient photothermal catalysts.

6.
Small ; 20(15): e2306809, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38009781

RESUMEN

The diagnosis and evaluation of traumatic brain injury (TBI) are crucial steps toward the treatment and prognosis of patients. A common question remains as to whether it is possible to introduce an ideal device for signal detection and evaluation that can directly connect digital signals with TBI, thereby enabling prompt response of the evaluation signal and sensitive and specific functioning of the detection process. Herein, a method is presented utilizing polymetric porous membranes with TRTK-12 peptide-modified nanochannels for the detection of S100B (a TBI biomarker) and assessment of TBI severity. The method leverages the specific bonding force between TRTK-12 peptide and S100B protein, along with the nanoconfinement effect of nanochannels, to achieve high sensitivity (LOD: 0.002 ng mL-1) and specificity (∆I/I0: 44.7%), utilizing ionic current change as an indicator. The proposed method, which is both sensitive and specific, offers a simple yet responsive approach for real-time evaluation of TBI severity. This innovative technique provides valuable scientific insights into the advancement of future diagnostic and therapeutic integration devices.


Asunto(s)
Biomimética , Lesiones Traumáticas del Encéfalo , Humanos , Péptidos , Lesiones Traumáticas del Encéfalo/diagnóstico , Pronóstico , Biomarcadores , Subunidad beta de la Proteína de Unión al Calcio S100
7.
Small ; : e2310175, 2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38402424

RESUMEN

Van der Waals semiconductors (vdWS) offer superior mechanical and electrical properties and are promising for flexible microelectronics when combined with polymer substrates. However, the self-passivated vdWS surfaces and their weak adhesion to polymers tend to cause interfacial sliding and wrinkling, and thus, are still challenging the reliability of vdWS-based flexible devices. Here, an effective covalent vdWS-polymer lamination method with high stretch tolerance and excellent electronic performance is reported. Using molybdenum disulfide (MoS2 )and polydimethylsiloxane (PDMS) as a case study, gold-chalcogen bonding and mercapto silane bridges are leveraged. The resulting composite structures exhibit more uniform and stronger interfacial adhesion. This enhanced coupling also enables the observation of a theoretically predicted tension-induced band structure transition in MoS2 . Moreover, no obvious degradation in the devices' structural and electrical properties is identified after numerous mechanical cycle tests. This high-quality lamination enhances the reliability of vdWS-based flexible microelectronics, accelerating their practical applications in biomedical research and consumer electronics.

8.
Small ; : e2400149, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528389

RESUMEN

Layered Na2FePO4F (NFPF) cathode material has received widespread attention due to its green nontoxicity, abundant raw materials, and low cost. However, its poor inherent electronic conductivity and sluggish sodium ion transportation seriously impede its capacity delivery and cycling stability. In this work, NFPF by Ti doping and conformal carbon layer coating via solid-state reaction is modified. The results of experimental study and density functional theory calculations reveal that Ti doping enhances intrinsic conductivity, accelerates Na-ion transport, and generates more Na-ion storage sites, and pyrolytic carbon from polyvinylpyrrolidone (PVP) uniformly coated on the NFPF surface improves the surface/interface conductivity and suppresses the side reactions. Under the combined effect of Ti doping and carbon coating, the optimized NFPF (marked as 5T-NF@C) exhibits excellent electrochemical performance, with a high capacity of 108.4 mAh g-1 at 0.2C, a considerable capacity of 80.0 mAh g-1 even at high current density of 10C, and a high capacity retention rate of 81.8% after 2000 cycles at 10C. When assembled into a full cell with a hard carbon anode, 5T-NF@C also show good applicability. This work indicates that co-modification of Ti doping and carbon coating makes NFPF achieve high rate and long cycle performance for sodium-ion batteries.

9.
Am J Pathol ; 193(9): 1234-1247, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37611970

RESUMEN

Chondrocyte survival is critical for the preservation of a healthy cartilage matrix. Limited chondrocyte function and survival can result in articular cartilage failure, thereby contributing to osteoarthritis (OA). In this study, miR-5581 was significantly up-regulated in OA samples, and miR-5581-associated genes were enriched in Kras signaling. miR-5581 up-regulation was observed in clinical OA samples and IL-1ß-stimulated chondrocytes. miR-5581 inhibition attenuated IL-1ß-induced chondrocyte proliferation suppression, extracellular matrix (ECM) synthesis suppression and degradation, and IL-1ß-suppressed Kras signaling activation. miR-5581 was targeted to inhibit NRF1. In IL-1ß-treated chondrocytes, NRF1 overexpression attenuated IL-1ß-induced cellular damage and partially abolished the effects of miR-5581 overexpression on IL-1ß-stimulated chondrocytes. NRF1 was down-regulated in knee joint cartilage of OA mice. In conclusion, miR-5581, which was up-regulated in OA samples and IL-1ß-stimulated chondrocytes, inhibited chondrocyte proliferation and ECM synthesis, and promoted ECM degradation through targeting NRF1, whereby Kras signaling might be involved.


Asunto(s)
MicroARNs , Osteoartritis , Animales , Ratones , Proliferación Celular , Condrocitos , MicroARNs/genética , Osteoartritis/genética , Proteínas Proto-Oncogénicas p21(ras)
10.
Chaos ; 34(7)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38980380

RESUMEN

Neural networks are popular data-driven modeling tools that come with high data collection costs. This paper proposes a residual-based multipeaks adaptive sampling (RMAS) algorithm, which can reduce the demand for a large number of samples in the identification of stochastic dynamical systems. Compared to classical residual-based sampling algorithms, the RMAS algorithm achieves higher system identification accuracy without relying on any hyperparameters. Subsequently, combining the RMAS algorithm and neural network, a few-shot identification (FSI) method for stochastic dynamical systems is proposed, which is applied to the identification of a vegetation biomass change model and the Rayleigh-Van der Pol impact vibration model. We show that the RMAS algorithm modifies residual-based sampling algorithms and, in particular, reduces the system identification error by 76% with the same sample sizes. Moreover, the surrogate model accurately predicts the first escape probability density function and the P bifurcation behavior in the systems, with the error of less than 1.59×10-2. Finally, the robustness of the FSI method is validated.

11.
Mikrochim Acta ; 191(7): 391, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38874626

RESUMEN

An ultra-high sensitivity pH sensor based on vertical organic electrochemical transistors (vOECT) with extended gate was proposed. The vOECT, which exhibited high transconductance (gm), was for the first time used in the preparation of a pH sensor. The extended gate was modified by electrochemical deposition of polyaniline (PANI) using the cyclic voltammetry (CV) technique. Open circuit potential (OCP) measurements were used to optimize the scan rate, showing a super-Nernstian sensitivity at all scan rates. The pH sensor based on vOECT with extended gate was investigated at different pH levels, and it exhibited an ultra-high sensitivity of 3363.6 µA/pH in the pH range 5-9, which was about 36 times greater than the maximum current sensitivity (91 µA/pH) of other transistor-based pH sensors, to the best of our knowledge. This pH sensor performed excellently in terms of reversibility, long-term stability, and selectivity. To confirm the reliability of the pH sensor, we conducted measurements on real samples using this pH sensor and compared the results with those obtained from a standard pH meter. The ultra-high sensitivity pH sensor based on vOECT with extended gate offers a sensitive and promising alternative in environmental monitoring, food safety, chemistry, clinical diagnostics, and bio-sensing applications.

12.
J Craniofac Surg ; 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38363289

RESUMEN

BACKGROUND: Sylvian aqueduct syndrome is a rare complication after ventriculoperitoneal (V-P) shunt surgery and is not easily diagnosed. METHODS: A 26-year-old male with obstructive hydrocephalus due to tectal glioma was treated with a V-P shunt surgery in another hospital. After the surgery, the patient developed an intractable disturbance of consciousness. When the V-P shunt pressure was raised or lowered, the patient's consciousness disorder still could not be improved. The patient was diagnosed with Sylvian aqueduct syndrome, a rare complication after V-P shunt operation. RESULTS: The paper clarifies the treatment experience with simultaneous endoscopic third ventriculostomy (ETV) and tectum gliomas biopsy, postoperative pathology suggestive of fibrillary astrocytoma; after surgery, the Sylvian aqueduct syndrome was cured and the patient recovered well. CONCLUSIONS: The preferred treatment for obstructive hydrocephalus caused by tumors in the Pineal region is the ETV operation. If an ETV operation and biopsy operation are performed simultaneously, more details need to be noted.

13.
J Craniofac Surg ; 35(4): 1258-1260, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38687036

RESUMEN

OBJECTIVE: Report on a case of pseudoaneurysm which was caused by injury of the internal carotid artery (ICA) during endoscopic endonasal surgery (EES), which was followed by rebleeding after treatment with a Willis covered stent. METHODS: A woman, aged 68, underwent EES for the treatment of a pituitary adenoma. During the surgery, the right ICA was injured, and successfully hemostasis by packed with cottonoid and gelatin sponge. Besides, cerebral angiography was performed in the interventional operating room for the purpose of discovering the formation of a pseudoaneurysm in the cavernous sinus segment of ICA, which was treated with a covered stent. After successfully placing the covered stent, the patient was promptly transferred to the general operating room for the removal of the cottonoid and to address the bleeding once again. The authors employ crushed muscles and cottonoid to locally compress and stop bleeding. Owing to concerns about the risk of rebleeding in the patient, after stent implantation, the patient did not utilize antiplatelet drugs. After the surgery, the patient developed occlusion of the right ICA and massive cerebral infarction in the right hemisphere. Dehydration, anti-infection, rehabilitation, hyperbaric oxygen, as well as related treatments, were given. The cottonoid was removed in EES 2 months postsurgery, and no instances of bleeding were observed. Six months after surgery, the patient had clear consciousness and hemiplegia in the left limb, with a Glasgow Outcome Scale score of 4. RESULTS: The ICA was injured during EES, which resulted in the formation of a pseudoaneurysm, the Willis stent was adopted for treatment, and there was a risk of rebleeding after the nasal packing (cottonoid, crushed muscles) was removed immediately. CONCLUSIONS: The ICA was injured during EES after bleeding was controlled by packing with cottonoid, crushed muscles, etc, subsequently, the patient was given intravascular treatment, it is advised to make thorough preparations and, after a suitable period, remove nasal packing in the hybrid operating room to address unexpected situations and unforeseen circumstances.


Asunto(s)
Traumatismos de las Arterias Carótidas , Arteria Carótida Interna , Neoplasias Hipofisarias , Stents , Humanos , Femenino , Traumatismos de las Arterias Carótidas/etiología , Traumatismos de las Arterias Carótidas/cirugía , Traumatismos de las Arterias Carótidas/terapia , Neoplasias Hipofisarias/cirugía , Anciano , Arteria Carótida Interna/cirugía , Adenoma/cirugía , Endoscopía/métodos , Aneurisma Falso/etiología , Aneurisma Falso/cirugía , Aneurisma Falso/terapia , Aneurisma Falso/diagnóstico por imagen , Angiografía Cerebral , Recurrencia , Complicaciones Intraoperatorias/etiología
14.
Chem Soc Rev ; 52(2): 601-662, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36149439

RESUMEN

Chemical warfare agents (CWAs) are toxic chemicals that have been intentionally developed for targeted and deadly use on humans. Although intended for military targets, the use of CWAs more often than not results in mass civilian casualties. To prevent further atrocities from occurring during conflicts, a global ban was implemented through the chemical weapons convention, with the aim of eliminating the development, stockpiling, and use of CWAs. Unfortunately, because of their relatively low cost, ease of manufacture and effectiveness on mass populations, CWAs still exist in today's world. CWAs have been used in several recent terrorist-related incidents and conflicts (e.g., Syria). Therefore, they continue to remain serious threats to public health and safety and to global peace and stability. Analytical methods that can accurately detect CWAs are essential to global security measures and for forensic analysis. Small molecule fluorescent probes have emerged as attractive chemical tools for CWA detection, due to their simplicity, ease of use, excellent selectivity and high sensitivity, as well as their ability to be translated into handheld devices. This includes the ability to non-invasively image CWA distribution within living systems (in vitro and in vivo) to permit in-depth evaluation of their biological interactions and allow potential identification of therapeutic countermeasures. In this review, we provide an overview of the various reported fluorescent probes that have been designed for the detection of CWAs. The mechanism for CWA detection, change in optical output and application for each fluorescent probe are described in detail. The limitations and challenges of currently developed fluorescent probes are discussed providing insight into the future development of this research area. We hope the information provided in this review will give readers a clear understanding of how to design a fluorescent probe for the detection of a specific CWA. We anticipate that this will advance our security systems and provide new tools for environmental and toxicology monitoring.


Asunto(s)
Sustancias para la Guerra Química , Humanos , Sustancias para la Guerra Química/análisis , Colorantes Fluorescentes
15.
Int J Mol Sci ; 25(10)2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38791283

RESUMEN

Fruit color is an intuitive quality of horticultural crops that can be used as an evaluation criterion for fruit ripening and is an important factor affecting consumers' purchase choices. In this study, a genetic population from the cross of green peel 'Qidong' and purple peel '8 guo' revealed that the purple to green color of eggplant peel is dominant and controlled by a pair of alleles. Bulked segregant analysis (BSA), SNP haplotyping, and fine genetic mapping delimited candidate genes to a 350 kb region of eggplant chromosome 10 flanked by markers KA2381 and CA8828. One ANS gene (EGP22363) was predicted to be a candidate gene based on gene annotation and sequence alignment of the 350-kb region. Sequence analysis revealed that a single base mutation of 'T' to 'C' on the exon green peel, which caused hydrophobicity to become hydrophilic serine, led to a change in the three-level spatial structure. Additionally, EGP22363 was more highly expressed in purple peels than in green peels. Collectively, EGP22363 is a strong candidate gene for anthocyanin biosynthesis in purple eggplant peels. These results provide important information for molecular marker-assisted selection in eggplants, and a basis for analyzing the regulatory pathways responsible for anthocyanin biosynthesis in eggplants.


Asunto(s)
Antocianinas , Mapeo Cromosómico , Frutas , Solanum melongena , Solanum melongena/genética , Solanum melongena/metabolismo , Antocianinas/biosíntesis , Antocianinas/genética , Frutas/genética , Frutas/metabolismo , Pigmentación/genética , Polimorfismo de Nucleótido Simple , Genes de Plantas , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
16.
J Environ Manage ; 365: 121475, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38905792

RESUMEN

Many urban water bodies grapple with low flow flux and weak hydrodynamics. To address these issues, projects have been implemented to form integrated urban water bodies via interconnecting artificial lake or ponds with rivers, but causing pollution accumulation downstream and eutrophication. Despite it is crucial to assess eutrophication, research on this topic in urban interconnected water bodies is limited, particularly regarding variability and feasible strategies for remediation. This study focused on the Loucun river in Shenzhen, comprising an pond, river and artificial lake, evaluating water quality changes pre-(post-)ecological remediation and establishing a new method for evaluating the water quality index (WQI). The underwater forest project, involving basement improvement, vegetation restoration, and aquatic augmentation, in the artificial lake significantly reduced total nitrogen (by 43.58%), total phosphorus (by 79.17%) and algae density (by 36.90%) compared to pre-remediation, effectively controlling algal bloom. Rainfall, acting as a variable factor, exacerbated downstream nutrient accumulation, increasing total phosphorus by 4.56 times and ammonia nitrogen by 1.30 times compared to the dry season, and leading to algal blooms in the non-restoration pond. The improved WQI method effectively assesses water quality status. The interconnected water body exhibits obvious nutrient accumulation in downstream regions. A combined strategy that reducing nutrient and augmenting flux was verified to alleviate accumulation of nutrients downstream. This study provides valuable insights into pollution management strategies for interconnected pond-river-lake water bodies, offering significant reference for nutrient mitigation in such urban water bodies.


Asunto(s)
Eutrofización , Fósforo , Fósforo/análisis , Calidad del Agua , Nitrógeno/análisis , Ríos , Lagos , Monitoreo del Ambiente/métodos , Restauración y Remediación Ambiental/métodos
17.
Environ Geochem Health ; 46(4): 135, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38483670

RESUMEN

Some Polycyclic Aromatic Compounds (PACs) such as nitrated-PAHs (NPAHs), oxygenated-PAHs (OPAHs) and methyl-PAHs (MPAHs) have attracted significant concern due to derivatives have greater potential to be more toxic at low environmental concentrations compared to their PPAHs, particularly in petrochemical industrial region and its surrounding areas surface soils in China. Hence, this article provides an insight into the fate, sources, impacts, and relevance to the external environment of PAH-derivatives based on important emissions source. Moreover, prospective health risk due to their exposure has also been discussed. In this study, the concentration (10-3 ng/g) of Æ©18PPAHs, Æ©11MPAHs, Æ©12NPAHs, and Æ©4OPAHs in the park were 9.67 ± 1.40, 3.24 ± 0.54, 0.03 ± 0.02 and 0.19 ± 0.65, respectively, which were 4.47, 3.89, 2.04 and 1.17 times than of them surrounding the region. A decreasing trend of the low molecular weight (2-4Rings) contribution to the total amount of PAHs, while the fraction of high molecular weight (5-6Rings) species showed the opposite trend. According to the principal component analysis (PCA) and diagnostic ratios indicated PAHs in the soil samples have mixed sources from industrial activities, solid fuel combustion, and heavy traffic. Despite the high concentrations of MPAHs and OPAHs, the toxicity equivalency quotients (TEQs) of them were not calculated due to the lack of toxic equivalent factors (TEF), thus current studies on PAH and derivatives could have underestimated their exposure risks. The quality and sustainable management of soils are crucial for human health and sustainable development, while there is lack of public awareness of the severe issue of soil pollution. It is recommended to conduct more intensive monitoring and regional assessments in the future.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Compuestos Policíclicos , Contaminantes del Suelo , Humanos , Compuestos Policíclicos/análisis , Monitoreo del Ambiente , Suelo , Hidrocarburos Policíclicos Aromáticos/toxicidad , Hidrocarburos Policíclicos Aromáticos/análisis , China , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Medición de Riesgo
18.
Angew Chem Int Ed Engl ; 63(17): e202401477, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38419469

RESUMEN

Voltage-gated ion channels prevalent in neurons play important roles in generating action potential and information transmission by responding to transmembrane potential. Fabricating bio-inspired ionic transistors with ions as charge carriers will be crucial for realizing neuro-inspired devices and brain-liking computing. Here, we reported a two-dimensional nanofluidic ionic transistor based on a MXene membrane with sub-1 nm interlayer channels. By applying a gating voltage on the MXene nanofluidic, a transmembrane potential will be generated to active the ionic transistor, which is similar to the transmembrane potential of neuron cells and can be effectively regulated by changing membrane parameters, e.g., thickness, composition, and interlayer spacing. For the symmetric MXene nanofluidic, a high on/off ratio of ~2000 can be achieved by forming an ionic depletion or accumulation zone, contingent on the sign of the gating potential. An asymmetric PET/MXene-composited nanofluidic transitioned the ionic transistor from ambipolar to unipolar, resulting in a more sensitive gate voltage characteristic with a low subthreshold swing of 560 mV/decade. Furthermore, ionic logic gate circuits, including the "NOT", "NAND", and "NOR" gate, were implemented for neuromorphic signal processing successfully, which provides a promising pathway towards highly parallel, low energy consumption, and ion-based brain-like computing.


Asunto(s)
Encéfalo , Nitritos , Elementos de Transición , Potenciales de Acción , Iones , Potenciales de la Membrana
19.
Angew Chem Int Ed Engl ; 63(8): e202319289, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38185722

RESUMEN

Inherent chirality is used to describe chiral cyclic molecules devoid of central, axial, planar, or helical chirality and has tremendous applications in chiral recognition and enantioselective synthesis. Catalytic and divergent syntheses of inherently chiral molecules have attracted increasing interest from chemists. Herein, we report the enantioselective synthesis of inherently chiral tribenzocycloheptene derivatives via chiral phosphoric acid (CPA)-catalyzed condensation of cyclic ketones and hydroxylamines. This chemistry paves the way to accessing the less stable derivatives of 7-membered rings with inherent chirality. A series of chiral tribenzocycloheptene oxime ethers was synthesized in good yields (up to 97 %) with excellent enantioselectivities (up to 99 % ee).

20.
Carcinogenesis ; 44(4): 328-340, 2023 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-36999803

RESUMEN

OBJECTIVES: Although great progress has made in gastric cancer (GC) in the past years, the overall 5-year survival rate remains to be low for advanced GC patients. A recent study showed that PLAGL2 was increased in GC and enhanced the proliferation and metastasis of GC. Nevertheless, the underlying mechanism still needs to be investigated. METHODS: Gene and protein expressions were assessed using RT-qPCR and western blot. The migration, proliferation and invasion of GC cells were examined using scratch assay, CCK-8 assay and Transwell assay, respectively. ChIP-PCR, dual-luciferase assay, RIP-qPCR and CoiP were utilized to confirm the interaction among PLAGL2, UCA1, miR-145-5p and YTHDF1 as well as METTL3, YTHDF1 and eEF-2. A mouse xenograft model was used utilized to further confirm the regulatory network. RESULTS: PLAGL2 bound to the upstream promoter of UCA1, which regulated YTHDF1 by sponging miR-145-5p. METTL3 can mediate the m6A modification level of Snail. YTHDF1 recognized m6A-modified Snail by interacting with eEF-2 and thus promoted Snail expression, which eventually induced epithelial-mesenchymal transition (EMT) in GC cells and metastasis of GC. CONCLUSIONS: Overall, our study demonstrates that PLAGL2 enhances Snail expression and GC progression via the UCA1/miR-145-5p/YTHDF1 axis, suggesting that PLAGL2 may become a therapeutic target for GC treatment.


Asunto(s)
MicroARNs , Neoplasias Gástricas , Animales , Humanos , Ratones , Línea Celular Tumoral , Proliferación Celular/genética , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica , Metiltransferasas/genética , Metiltransferasas/metabolismo , MicroARNs/genética , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Neoplasias Gástricas/patología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
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