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1.
Small ; : e2407038, 2024 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-39394989

RESUMEN

Photothermal therapy (PTT) against cancer not only directly ablates tumors but also induces tumor immunogenic cell death (ICD). However, the antitumor immune response elicited by ICD is insufficient to prevent relapse and metastasis because of the immunosuppressive tumor microenvironment (TME). A biomimetic nanoplatform (bmNP) mimicking cytotoxic lymphocytes (CTLs) for combinational photothermal-immunotherapy to effectively regulate the immunosuppressive TME is reported here. The bmNP is constructed by wrapping the T-cell membrane onto a new type of photothermal agents, spherical Au-based PNCs (sAuPNCs). Similar to T-cells, the bmNP enhanced accumulation at the tumor site by targeting the tumor via adhesion proteins on T-cell membrane. The obtained sAuPNCs have a wide absorption band in the second near-infrared (NIR-II) region with a high photothermal conversion efficiency (PCE) up to about 75% and excellent photostability. The bmNP with a smaller size is more superior compete with T-cells to bond with tumor cells via PD-1/PD-L1 interaction to effectively block the PD-1 checkpoint of T-cells for preventing T-cell exhaustion. Furthermore, in vivo studies reveal the immunological memory effect is significantly elicited in mice received bmNPs therapy. Collectively, bmNPs show great potential in photothermal-enhanced immunotherapy.

2.
J Mater Chem B ; 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39403919

RESUMEN

Sensitive imaging of microRNAs (miRNAs) in tumor cells holds great significance in the domains of pathology, drug development, and personalized diagnosis and treatment. DNA nanostructures possess excellent biostability and programmability and are suitable as carriers for intracellular imaging probes. With its highly controllable motion mechanism and remarkable target recognition specificity, the DNA walker is an ideal tool for living cell imaging. Here, we report a DNA nanowire based-DNAzyme Walker (D-Walker), which loads the DNAzyme based-molecular beacon (D-MB) onto DNA nanowires (NWs) functionalized with aptamers. The experimental results demonstrated that the intracellular target miRNA can specifically activate the pre-locked DNAzyme through a strand displacement reaction, thereby triggering the cleavage of its substrate molecular beacon (MB) and subsequent fluorescence emission. NWs decorated with aptamers can effectively prevent the degradation of the D-Walker by nuclease, and can enter target cells without any transfection reagents, which enhances the stability and reliability of cell imaging. Furthermore, the D-Walker exhibited a remarkable sensitivity with a limit of detection (LOD) of 61 pM and was capable of distinguishing miRNA-21 from other closely related family members. This study provides a novel strategy for intracellular miRNA imaging, offering a promising tool for cancer diagnosis and treatment.

3.
J Chromatogr A ; 1736: 465333, 2024 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-39260151

RESUMEN

A zwitterionic stationary phase comprising pyridinium cations and sulfonate anions was successfully developed through thiol-ene click chemistry. Using seven polar small molecules as probes, the zwitterionic stationary phase showed high separation selectivity and excellent column efficiency (35,200-54,800 plates/m) compared with two commercial columns. The influence of water proportion, salt concentration, and pH in the mobile phase, and column temperature, on the retention of six polar compounds was examined. The retention mechanism was explored by three hydrophilic retention models, Tanaka test and linear solvation energy relationship analysis. For the analysis of sample dairy products (milk powder, milk, and yogurt), the stationary phase was operated in hydrophilic interaction chromatography mode without the addition of buffer salts, facilitating rapid and efficient detection and quantification of melamine. The LOD and LOQ are 0.04 mg⋅g-1 and 0.13 mg⋅g-1, respectively, and the recovery rate is 90.3 - 102.8 %. The zwitterionic stationary phase has the advantages of simple preparation, good method reproducibility, good selectivity and high precision.


Asunto(s)
Betaína , Interacciones Hidrofóbicas e Hidrofílicas , Límite de Detección , Leche , Piridinas , Triazinas , Betaína/química , Betaína/análogos & derivados , Piridinas/química , Triazinas/química , Triazinas/análisis , Triazinas/aislamiento & purificación , Leche/química , Reproducibilidad de los Resultados , Animales , Cromatografía Líquida de Alta Presión/métodos , Ácidos Sulfónicos/química , Concentración de Iones de Hidrógeno , Química Clic
4.
J Chromatogr A ; 1736: 465349, 2024 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-39293277

RESUMEN

To deal with complicated separation situations, this study successfully prepared two mixed-mode chromatography (MMC) stationary phases, CCL-SIL and PCL-SIL, by functionalizing dialdehyde cellulose (DAC) derivatives. In liquid chromatography applications, CCL-SIL exhibited superior separation performance for nucleosides and bases in HILIC mode, while PCL-SIL performed better in RPLC and IEC modes. Their distinct separation mechanisms were also elucidated by quantum chemical calculations. Both CCL-SIL and PCL-SIL showed good stability and reproducibility, with relative standard deviations of retention time, peak area, and peak height below 7.79 % and 4.37 % for multiple injections. Particularly, the PCL-SIL column and the CCL-SIL column were successfully used for the quantitative analysis of trace targets in real samples with complex matrix, demonstrating high accuracy and precision.


Asunto(s)
Celulosa , Celulosa/análogos & derivados , Celulosa/química , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los Resultados , Nucleósidos/aislamiento & purificación , Nucleósidos/análisis , Nucleósidos/química , Interacciones Hidrofóbicas e Hidrofílicas
5.
Anal Chem ; 96(33): 13566-13575, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39105712

RESUMEN

The development of appropriate molecular tools to monitor different mercury speciation, especially CH3Hg+, in living organisms is attractive because its persistent accumulation and toxicity are very harmful to human health. Herein, we develop a novel activity-based ratiometric SERS nanoprobe to selectively monitor Hg2+ and CH3Hg+ in aqueous media and in vivo. In this nanoprobe, a new bifunctional Raman probe bis-s-s'-[(s)-(4-(ethylcarbamoyl)phenyl)boronic acid] (b-(s)-EPBA) was synthesized and immobilized on the surface of gold nanoparticles via a Au-S bond, in which the phenylboronic acid group was employed as the recognition unit for Hg2+ and CH3Hg+ based on the Hg-promoted transmetalation reaction. In the presence of Hg2+ and CH3Hg+, a new surface-enhanced Raman scattering (SERS) peak aroused from of C-Hg appeared at 1080 cm-1, and the SERS intensity at 1002 cm-1 belonged to the B-O symmetric stretching decreased simultaneously. The quantitative tracking of Hg2+ and CH3Hg+ was realized based on the SERS intensity ratio (I1080/I1303) with rapid response (∼4 min) and high sensitivity, with detection limits of 10.05 and 25.13 nM, respectively. Moreover, the SERS sensor was used for the quantitative detection of Hg2+ and CH3Hg+ in four actual water samples with a high accuracy and excellent recovery. More importantly, cell imaging experiments showed that AuNPs@b-(s)-EPBA could quantitatively detect intracellular CH3Hg+ and had a good concentration dependence in ratiometric SERS imaging. Meanwhile, we demonstrated that AuNPs@b-(s)-EPBA could detect and image CH3Hg+ in zebrafish. We anticipate that AuNPs@b-(s)-EPBA could potentially be used to study the physiological functions related to CH3Hg+ in the future.


Asunto(s)
Ácidos Borónicos , Oro , Mercurio , Nanopartículas del Metal , Espectrometría Raman , Espectrometría Raman/métodos , Ácidos Borónicos/química , Mercurio/análisis , Mercurio/química , Humanos , Nanopartículas del Metal/química , Oro/química , Animales , Pez Cebra , Propiedades de Superficie , Agua/química , Límite de Detección , Contaminantes Químicos del Agua/análisis
6.
Talanta ; 279: 126638, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39210548

RESUMEN

Detecting dopamine (DA) is critical for early diagnosis of neurological and psychiatric disorders. However, the presence of other catecholamine neurotransmitters with structural similarities to DA causes significant interference in its detection. Herein, we introduce S stripping defects via laser-induced MoS2 to functionalize MoS2 electrodes and improve their selectivity for DA electrochemical detection. The sensing results show its excellent immunity to interference from other neurotransmitters, ensuring the preservation of the DA electrochemical signal even in the mixed neurotransmitters such as acetylcholine (ACh), γ-aminobutyric acid (GABA), epinephrine (EP), norepinephrine (NP), and serotonin (5-HT). DFT calculations further reveal that the negatively charged S-stripping defects enhance DA adsorption on the surface of the functionalized MoS2 electrode, contributing to its excellent performance. Moreover, this functionalized electrodes successfully monitor DA released from living PC12 cells in the presence of other interference, highlighting its potential applicability in intercellular signaling communication.


Asunto(s)
Dopamina , Técnicas Electroquímicas , Electrodos , Rayos Láser , Neurotransmisores , Dopamina/análisis , Células PC12 , Técnicas Electroquímicas/métodos , Animales , Neurotransmisores/análisis , Ratas , Disulfuros/química , Catecolaminas/análisis , Epinefrina/análisis , Norepinefrina/análisis , Teoría Funcional de la Densidad , Molibdeno
7.
Front Microbiol ; 15: 1433046, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39104579

RESUMEN

Water reservoir sediments represent a distinct habitat that harbors diverse microbial resources crucial for nitrogen cycling processes. The discovery of resuscitation promoting factor (Rpf) has been recognized as a crucial development in understanding the potential of microbial populations. However, our understanding of the relationship between microorganisms containing rpf-like genes and nitrogen-cycling functional populations remains limited. The present study explored the distribution patterns of rpf-like genes and nitrogen-cycling genes in various water reservoir sediments, along with their correlation with environmental factors. Additionally, the co-occurrence of rpf-like genes with genes associated with the nitrogen cycle and viable but non-culturable (VBNC) formation was investigated. The findings indicated the ubiquitous occurrence of Rpf-like domains and their related genes in the examined reservoir sediments. Notably, rpf-like genes were predominantly associated with Bradyrhizobium, Nitrospira, and Anaeromyxobacter, with pH emerging as the primary influencing factor for their distribution. Genera such as Nitrospira, Bradyrhizobium, Anaeromyxobacter, and Dechloromonas harbor the majority of nitrogen-cycling functional genes, particularly denitrification genes. The distribution of nitrogen-cycling microbial communities in the reservoir sediments was mainly influenced by pH and NH4 +. Notably, correlation network analysis revealed close connections between microorganisms containing rpf-like genes and nitrogen-cycling functional populations, as well as VBNC bacteria. These findings offer new insights into the prevalence of rpf-like genes in the water reservoir sediments and their correlation with nitrogen-cycling microbial communities, enhancing our understanding of the significant potential of microbial nitrogen cycling.

8.
Anal Chem ; 96(35): 14215-14221, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39162214

RESUMEN

Atherosclerosis (AS) is the leading cause of cardiovascular disease. Foam cells, with elevated lipid droplets (LDs) and HClO levels, are the main components of the atherosclerotic plaques that are characteristic of AS. Super-resolution imaging can be used to visualize the distribution of LDs in foam cells at the nanometer level, facilitating the identification of LDs and HClO. In the present study, we report the development of a ratiometric fluorescent probe, SFL-HClO, for super-resolution imaging of LDs and HClO. Super-resolution imaging with this probe revealed the precise structure of LDs at the suborganelle level. Moreover, the fluorescence behavior of SFL-HClO on the surface of LDs verified its excellent performance in detecting HClO in the foam cells. SFL-HClO can sequentially and specifically respond to LDs and HClO via "turn-on" and ratiometric signal output, respectively, thus contributing to precise imaging of foam cells. Importantly, we demonstrate that SFL-HClO can be used to report on upregulated HClO in atherosclerotic plaques in the aorta of AS mice, providing a suitable fluorescent tool for early atherosclerotic disease assessment.


Asunto(s)
Aterosclerosis , Colorantes Fluorescentes , Células Espumosas , Ácido Hipocloroso , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Células Espumosas/patología , Animales , Aterosclerosis/diagnóstico por imagen , Aterosclerosis/patología , Ratones , Ácido Hipocloroso/análisis , Células RAW 264.7 , Imagen Óptica , Humanos , Placa Aterosclerótica/diagnóstico por imagen , Placa Aterosclerótica/química , Placa Aterosclerótica/patología , Ratones Endogámicos C57BL , Gotas Lipídicas/química
9.
Anal Chem ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39133550

RESUMEN

Analyzing trace-level volatile organic compounds (VOCs) remains challenging due to initial sampling and preconcentration limitations. Inspired by the highly reproducible and constantly renewable electrode surface of dropping mercury electrode (DME), a contactless enrichment process was first reported by using an acoustic levitation device to trap and concentrate VOCs from gas samples onto suspended droplets, which were then directly transferred into gas chromatography-mass spectrometry (GC-MS) for real-time analysis. Compared with traditional methods injection methods, this method achieves a 46-fold increase in nicotine peak area. The detection sensitivity was enhanced significantly, attributed to the high specific surface area of the droplets and the accelerating extraction vibration. Notably, the number of identified VOCs from burning cigarettes significantly increased from 17 to 212, including 22 aromatic compounds with distinct aromas. The remarkable versatility of this method was demonstrated by effectively monitoring the dynamic changes of 16 VOCs in environmental tobacco smoke (ETS) following cigarette burning, revealing the persistence of these compounds, even after 40 min. Moreover, directly analyzing human-exhaled aerosol found that nicotine rapidly decreased while its metabolite cotinine increased, showcasing the potential for tracking human metabolism and behavior in vivo. Furthermore, multivariate data analysis of VOC profiles from six cigarette brands allowed for their visual differentiation. With versatility, sensitivity, and the ability to distinguish trace-level VOCs in realtime, this method offers promising avenues for environmental monitoring, metabolic studies, and various analytical applications.

10.
J Chromatogr A ; 1730: 465113, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-38959656

RESUMEN

Ionic covalent organic frameworks with both crystallinity and charged sites have attracted significant attention from the scientific community. The versatile textural structures, precisely defined channels, and abundant charged sites of ionic COFs offer immense potential in various areas such as separation, sample pretreatment, ion conduction mechanisms, sensing applications, catalytic reactions, and energy storage systems. This review presents a comprehensive overview of facile preparation methods for ionic covalent organic frameworks (iCOFs), along with their applications in food sample pretreatment techniques such as solid-phase extraction (SPE), magnetic solid-phase extraction (MSPE), and dispersive solid-phase extraction (DSPE). Furthermore, it highlights the extensive utilization of iCOFs in detecting various food contaminants including pesticides, contaminants from food packaging, veterinary drugs, perfluoroalkyl substances, and poly-fluoroalkyl substances. Specifically, this review critically discusses the limitations, challenges, and future prospects associated with employing iCOF materials to ensure food safety.


Asunto(s)
Análisis de los Alimentos , Contaminación de Alimentos , Estructuras Metalorgánicas , Extracción en Fase Sólida , Estructuras Metalorgánicas/química , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Extracción en Fase Sólida/métodos , Plaguicidas/análisis , Plaguicidas/química , Embalaje de Alimentos
11.
Chem Commun (Camb) ; 60(62): 8115-8118, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-38994726

RESUMEN

We pioneered an angle-adjustable photonic crystal fluorescence platform (APC-Fluor) that integrates PCs, an angular resolution spectrometer and a strategically aligned laser source. This configuration, featuring a coaxial rotating swing arm, allows for precise control over the angles of incidence and emission. The presence of photonic crystal microcavities facilitates the dispersion of fluorescent materials and promotes the transition of electrons from the excited state to the lowest vibrational energy level. The optical resonance effect triggered by modulating the alignment of the reflection peaks of the photonic crystals with the emission peaks of the fluorescent materials can significantly enhance the fluorescence intensity. Compared with the single BSA-AuNCs, the optimized fluorescence intensity can be significantly increased by 11.9-fold. The APC-Fluor system showcases rapid and highly sensitive detection capabilities for oxytetracycline (OTC), exhibiting a response across a concentration range from 2 to 1 × 104 nM and achieving a notably low detection limit of 1.03 nM.

12.
Environ Res ; 261: 119699, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39074776

RESUMEN

The investigation into viable but non-culturable (VBNC) bacteria through the implementation of resuscitation promoting factors (Rpfs) has broadened the potential sources for isolating strains capable of degrading polychlorinated biphenyls (PCBs). Nonetheless, there has been limited research on the efficacy of resuscitated strains and the potential improvement of their performance through co-cultivation. In this work, the PCB degradation potential of resuscitated strains, specifically Pseudomonas sp. HR1 and Achromobacter sp. HR2, as well as their co-cultures, was investigated. Of particular importance was the comparative analysis between the optimal co-culture and individual strains regarding their ability to degrade PCB homologs and mineralize intermediate metabolites. The results suggested that the resuscitated strains HR1 and HR2 demonstrated robust growth and effective degradation of Aroclor 1242. The co-culture CO13, with an optimal HR1 to HR2 ratio of 1:3, exhibited a remarkable improvement in PCB degradation and intermediate metabolite mineralization compared to individual strains. Analysis of functional genes and degradation metabolites revealed that both the individual strains and co-culture CO13 degraded PCBs via the HOPDA-benzoate pathway, then mineralized through protocatechuate meta- and ortho-cleavage pathways, as well as the catechol ortho-cleavage pathway. This study represents the first documentation of the improved PCB degradation through the co-cultivation of resuscitated strains, which highlights the great promise of these resuscitated strains and their co-cultures as effective bio-inoculants for enhanced bioremediation.


Asunto(s)
Biodegradación Ambiental , Técnicas de Cocultivo , Bifenilos Policlorados , Bifenilos Policlorados/metabolismo , Pseudomonas/metabolismo , Achromobacter/metabolismo , Achromobacter/genética , Arocloros/metabolismo
13.
J Environ Manage ; 366: 121877, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39018860

RESUMEN

Sulfur-driven autotrophic denitrification (S0dAD) was employed to remove residual nitrogen from the biological effluent of landfill leachate after partial nitrification and denitrification pretreatment. The performance of S0dAD were assessed with various NOx--N (NO2--N and NO3--N) loadings over a 185-day operational period. The results demonstrated that a notable NOx--N removal efficiency of 97.8 ± 2.0% was achieved under nitrogen removal rates of 0.12 ± 0.02 kg N/(m3· d), leading to total nitrogen concentrations of 8.6 ± 3.8 mg/L in the effluent. Batch experiments revealed competitive utilization of nitrogenous electron acceptors, with NO2--N demonstrating 2-4 times higher denitrification rates than NO3--N under coexistence conditions. Genus-level microbial community identified that Thiobacillus and Sulfurovum was highly enriched with as key denitrifying bacteria in the S0dAD system. These findings provide insights for advanced nitrogen removal coupling S0dAD with partial nitrification and denitrification process for landfill leachate treatment.


Asunto(s)
Desnitrificación , Nitrificación , Nitrógeno , Azufre , Contaminantes Químicos del Agua , Nitrógeno/metabolismo , Azufre/metabolismo , Contaminantes Químicos del Agua/metabolismo , Procesos Autotróficos
14.
ACS Appl Bio Mater ; 7(8): 5337-5344, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-38968606

RESUMEN

Cerium oxide (CeO2-x) performs well in photothermal and catalytic properties due to its abundance of oxygen vacancies. Based on this, we designed a thermosensitive therapeutic nanoplatform to achieve continuous circular drug release in tumor. It can solve the limitation caused by insufficient substrate in the process of tumor treatment. Briefly, CeO2-x and camptothecin (CPT) were wrapped in an agarose hydrogel, which could be melted by the photothermal effect of CeO2-x. At the same time, the local temperature increase provided photothermal treatment, which could induce the apoptosis of tumor cell. After that, CPT was released to damage the DNA in tumor cells to realize chemical treatment. In addition, CPT could active nicotinamide adenine dinucleotide oxidase to react with O2 to increase the intracellular H2O2. After that, the exposed CeO2-x could catalyze H2O2 to generate cytotoxic reactive oxygen species for chemodynamic therapy. More importantly, CeO2-x could catalyze H2O2 to produce O2, which could combine with the catalytic action of CPT to construct a substrate self-cycling nanoenzyme system. Overall, this self-cycling nanoplatform released hypoxia in the tumor microenvironment and built a multimode tumor treatment, which achieved an ideal antitumor affect.


Asunto(s)
Materiales Biocompatibles , Cerio , Ensayo de Materiales , Cerio/química , Cerio/farmacología , Humanos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Tamaño de la Partícula , Animales , Ratones , Camptotecina/química , Camptotecina/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/metabolismo , Temperatura
15.
Anal Chem ; 96(28): 11581-11587, 2024 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-38951996

RESUMEN

Ferroptosis is an iron-dependent programmed cell death that is characterized by the dysregulation of lipid reactive oxygen species (ROS) production, causing abnormal changes in hypochlorous acid (HClO) levels in lysosomes. Super-resolution imaging can observe the fine structure of the lysosome at the nanometer level; therefore, it can be used to detect lysosome HClO levels during ferroptosis at the suborganelle level. Herein, we utilize a ratiometric fluorescent probe, SRF-HClO, for super-resolution imaging of lysosome HClO. Structured-illumination microscopy (SIM) improves the accuracy of lysosome targeting and enables the probe SRF-HClO to be successfully applied to rapidly monitor the up-regulated lysosome HClO at the nanoscale during inflammation and ferroptosis. Importantly, the probe SRF-HClO can also detect HClO changes in inflammatory and ferroptosis mice and evaluate the inhibitory effect of ferroptosis on mice tumors.


Asunto(s)
Ferroptosis , Colorantes Fluorescentes , Ácido Hipocloroso , Lisosomas , Ferroptosis/efectos de los fármacos , Colorantes Fluorescentes/química , Ácido Hipocloroso/análisis , Ácido Hipocloroso/metabolismo , Lisosomas/química , Lisosomas/metabolismo , Animales , Ratones , Humanos , Imagen Óptica , Células RAW 264.7
16.
Animals (Basel) ; 14(11)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38891686

RESUMEN

Human-wildlife conflicts are becoming increasingly common worldwide and are a challenge to biodiversity management. Compared with compensatory management, which often focuses on solving emergency conflicts, mitigation management allows decision-makers to better understand where the damage is distributed, how the species are distributed and when the species conduct their activity. Here, we integrated data collected from 90 districts/counties' damage surveys and 1271 camera traps to understand the damage status, abundance, density and activity rhythms of wild boar (Sus scrofa) in Zhejiang, Eastern China, from January 2019 to August 2023. We found that (1) wild boar-human conflicts were mainly distributed in the northwest and southwest mountainous regions of Zhejiang Province; (2) the total abundance of wild boar was 115,156 ± 24,072 individuals, indicating a growing trend over the past decade and a higher density in the western and southern regions; (3) wild boar exhibited different activity patterns across different damage regions, and the periods around 7:00, 11:00 and 16:00 represented activity peaks for wild boar in seriously damaged regions. The damage distribution, density, distribution and activity rhythms provide specific priority regions and activity intensity peaks for conflict mitigation. We believe that these findings based on the damage, distribution and activity could provide a scientific basis for mitigation management at the county level and enrich the framework of human-wildlife conflict mitigation.

17.
Int J Mol Sci ; 25(11)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38892163

RESUMEN

Extreme weather poses huge challenges for animals that must adapt to wide variations in environmental temperature and, in many cases, it can lead to the local extirpation of populations or even the extinction of an entire species. Previous studies have found that one element of amphibian adaptation to environmental stress involves changes in mitochondrial gene expression at low temperatures. However, to date, comparative studies of gene expression in organisms living at extreme temperatures have focused mainly on nuclear genes. This study sequenced the complete mitochondrial genomes of five Asian hylid frog species: Dryophytes japonicus, D. immaculata, Hyla annectans, H. chinensis and H. zhaopingensis. It compared the phylogenetic relationships within the Hylidae family and explored the association between mitochondrial gene expression and evolutionary adaptations to cold stress. The present results showed that in D. immaculata, transcript levels of 12 out of 13 mitochondria genes were significantly reduced under cold exposure (p < 0.05); hence, we put forward the conjecture that D. immaculata adapts by entering a hibernation state at low temperature. In H. annectans, the transcripts of 10 genes (ND1, ND2, ND3, ND4, ND4L, ND5, ND6, COX1, COX2 and ATP8) were significantly reduced in response to cold exposure, and five mitochondrial genes in H. chinensis (ND1, ND2, ND3, ND4L and ATP6) also showed significantly reduced expression and transcript levels under cold conditions. By contrast, transcript levels of ND2 and ATP6 in H. zhaopingensis were significantly increased at low temperatures, possibly related to the narrow distribution of this species primarily at low latitudes. Indeed, H. zhaopingensis has little ability to adapt to low temperature (4 °C), or maybe to enter into hibernation, and it shows metabolic disorder in the cold. The present study demonstrates that the regulatory trend of mitochondrial gene expression in amphibians is correlated with their ability to adapt to variable climates in extreme environments. These results can predict which species are more likely to undergo extirpation or extinction with climate change and, thereby, provide new ideas for the study of species extinction in highly variable winter climates.


Asunto(s)
Anuros , Genoma Mitocondrial , Filogenia , Animales , Anuros/genética , Anuros/fisiología , Respuesta al Choque por Frío/genética , Frío , Adaptación Fisiológica/genética , Regulación de la Expresión Génica
18.
Se Pu ; 42(6): 572-580, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-38845518

RESUMEN

Perfluorooctanoic acid (PFOA) is a persistent contaminant with detrimental effects on the natural environment. This persistence leads to potential enrichment and osmotic transfer, which can affect normal circulation in the environment. PFOA poses significant threats to both the natural environment and human health. Therefore, the development of cost-effective, highly efficient, and environment-friendly PFOA adsorbents is a crucial endeavor. This paper presents the catalyst-free one-pot synthesis of fluorinated nitrogen-rich porous organic polymers (POP-3F) via a Schiff-base condensation reaction. The reaction between the nitrogen-rich compound 1,4-bis(2,4-diamino-1,3,5-triazine)benzene and p-trifluoromethylbenzaldehyde yielded POP-3F. The introduction of fluorine atoms into the nitrogen-rich porous organic polymer enhanced its hydrophobicity, thereby facilitating favorable fluoro-fluorine interactions with PFOA and, thus, improving the efficacy of the adsorbent. Scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), solid-state nuclear magnetic resonance (ssNMR) spectroscopy, X-ray photoelectron spectroscopy (XPS), nitrogen adsorption-desorption analysis, and thermogravimetric analysis (TGA) were used to confirm the successful synthesis and characterization of POP-3F. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was conducted in negative electrospray ionization (ESI) mode coupled with multi-reaction monitoring mode (MRM). The instrument was equipped with an Atlantis T3 column (100 mm×2.1 mm, 3 µm), and analysis was conducted using an external standard method. The influences of various factors on PFOA adsorption by POP-3F, including pH, salt concentration, and humic acid presence, were investigated. The highest PFOA removal rate (98.6%) was achieved at a pH of 2, indicating the applicability of POP-3F for the effective removal of PFOA from acidic industrial wastewater. The removal rate of PFOA was unaffected by increases in NaCl concentration. This phenomenon can be attributed to electrostatic interactions between the protonated secondary amines in POP-3F and deprotonated PFOA. Upon the addition of NaCl, a double electric layer is formed on the POP-3F surface, with Cl- ions in the outer layer and Na+ ions in the inner layer, which weakened these interactions. Humic acid is competitively adsorbed with PFOA. However, POP-3F demonstrated good removal rates even in the presence of high humic acid concentrations in water. Adsorption isotherm and kinetics experiments were conducted at the optimal pH to explore the relevant adsorption mechanism. The results showed a rapid initial adsorption rate, with 95.4% PFOA removal within 5 min. Optimal adsorption equilibrium was achieved within 6 h, and the removal rate decreased by only 0.3% after 24 h. This finding indicates that POP-3F exhibits sustained efficacy for PFOA removal. Langmuir fitting analysis revealed a theoretical maximum adsorption capacity of 191 mg/g for POP-3F; this value surpasses those of activated carbon materials and most other adsorbents, highlighting the superior PFOA-adsorption performance of POP-3F. Additionally, matrix effects minimally affected the removal of PFOA by POP-3F, with only a slight reduction (0.1%) observed in simulated natural water. The recyclability of POP-3F was assessed over five adsorption-desorption cycles. The removal efficenecy exhibited a minor decrease of only 0.67% after five cycles. These results demonstrate the recyclability of the proposed adsorbent, which translates into cost reduction through reusability. This characteristic renders POP-3F a promising candidate for the economical and efficient removal of PFOA from wastewater in practical applications.

19.
Biomed Mater ; 19(4)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38772387

RESUMEN

Single-cell analysis is an effective method for conducting comprehensive heterogeneity studies ranging from cell phenotype to gene expression. The ability to arrange different cells in a predetermined pattern at single-cell resolution has a wide range of applications in cell-based analysis and plays an important role in facilitating interdisciplinary research by researchers in various fields. Most existing microfluidic microwell chips is a simple and straightforward method, which typically use small-sized microwells to accommodate single cells. However, this method imposes certain limitations on cells of various sizes, and the single-cell capture efficiency is relatively low without the assistance of external forces. Moreover, the microwells limit the spatiotemporal resolution of reagent replacement, as well as cell-to-cell communication. In this study, we propose a new strategy to prepare a single-cell array on a planar microchannel based on microfluidic flip microwells chip platform with large apertures (50 µm), shallow channels (50 µm), and deep microwells (50 µm). The combination of three configuration characteristics contributes to multi-cell trapping and a single-cell array within microwells, while the subsequent chip flipping accomplishes the transfer of the single-cell array to the opposite planar microchannel for cells adherence and growth. Further assisted by protein coating of bovine serum albumin and fibronectin on different layers, the single-cell capture efficiency in microwells is achieved at 92.1% ± 1%, while ultimately 85% ± 3.4% on planar microchannel. To verify the microfluidic flip microwells chip platform, the real-time and heterogeneous study of calcium release and apoptosis behaviours of single cells is carried out. To our knowledge, this is the first time that high-efficiency single-cell acquisition has been accomplished using a circular-well chip design that combines shallow channel, large aperture and deep microwell together. The chip is effective in avoiding the shearing force of high flow rates on cells, and the large apertures better allows cells to sedimentation. Therefore, this strategy owns the advantages of easy preparation and user-friendliness, which is especially valuable for researchers from different fields.


Asunto(s)
Microfluídica , Análisis de la Célula Individual , Análisis de la Célula Individual/métodos , Humanos , Microfluídica/métodos , Adhesión Celular , Animales , Diseño de Equipo , Técnicas Analíticas Microfluídicas/instrumentación , Dispositivos Laboratorio en un Chip , Fibronectinas/química , Fibronectinas/metabolismo , Calcio/metabolismo , Calcio/química , Albúmina Sérica Bovina/química , Comunicación Celular
20.
Biomed Pharmacother ; 175: 116787, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38788548

RESUMEN

Pulmonary hypertension (PH) is a cardiovascular disorder characterized by substantial morbidity and mortality rates. It is a chronic condition characterized by intricate pathogenesis and uncontrollable factors. We summarized the pathological effects of estrogen, genetics, neuroinflammation, intestinal microbiota, metabolic reorganization, and histone modification on PH. PH is not only a pulmonary vascular disease, but also a systemic disease. The findings emphasize that the onset of PH is not exclusively confined to the pulmonary vasculature, consequently necessitating treatment approaches that extend beyond targeting pulmonary blood vessels. Hence, the research on the pathological mechanism of PH is not limited to target organs such as pulmonary vessels, but also focuses on exploring other fields (such as estrogen, genetics, neuroinflammation, intestinal microbiota, metabolic reorganization, and histone modification).


Asunto(s)
Microbioma Gastrointestinal , Hipertensión Pulmonar , Humanos , Hipertensión Pulmonar/fisiopatología , Animales , Estrógenos/metabolismo , Enfermedades Neuroinflamatorias
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