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1.
Small ; 20(36): e2402841, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38693072

RESUMO

Developing lightweight composite with reversible switching between microwave (MW) absorption and electromagnetic interference (EMI) shielding is promising yet remains highly challenging due to the completely inconsistent attenuation mechanism for electromagnetic (EM) radiation. Here, a lightweight vanadium dioxide/expanded polymer microsphere composites foam (VO2/EPM) is designed and fabricated with porous structures and 3D VO2 interconnection, which possesses reversible switching function between MW absorption and EMI shielding under thermal stimulation. The VO2/EPM exhibits MW absorption with a broad effective absorption bandwidth of 3.25 GHz at room temperature (25 °C), while provides EMI shielding of 23.1 dB at moderately high temperature (100 °C). This reversible switching performance relies on the porous structure and tunability of electrical conductivity, complex permittivity, and impedance matching, which are substantially induced by the convertible crystal structure and electronic structure of VO2. Finite element simulation is employed to qualitatively investigate the change in interaction between EM waves and VO2/EPM before and after the phase transition. Moreover, the application of VO2/EPM is demonstrated with a reversible switching function in controlling wireless transmission on/off, showcasing its excellent cycling stability. This kind of smart material with a reversible switching function shows great potential in next-generation electronic devices.

2.
Protein Expr Purif ; 215: 106391, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939750

RESUMO

While purifying a regular monospecific antibody, we found that the Protein A step yield was much lower than expected. Further studies revealed that the antibody formed large-size aggregates that did not bind to the Protein A resin, hence leading to dropped recovery. In an attempt to solve this low yield issue, we found that mildly acidic pH or ammonium sulfate treatment can partially convert the aggregates into monomers. In addition, when acidic pH treated culture harvest was processed by Protein A chromatography, the yield was restored to the normal range, suggesting that the monomers recovered from aggregates regained Protein A binding capability. Thus, low pH treatment of culture harvest can be potentially used as a general approach for improving Protein A step yield in cases where non-binding antibody aggregates are formed through noncovalent interactions.


Assuntos
Anticorpos Monoclonais , Proteína Estafilocócica A , Anticorpos Monoclonais/química , Proteína Estafilocócica A/química , Cromatografia , Concentração de Íons de Hidrogênio
3.
Protein Expr Purif ; 216: 106418, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38141898

RESUMO

For a certain number of mAbs, bispecific antibodies (bsAbs) and Fc-fusion proteins that we worked on, the Protein A capture step experienced low yield (i.e., ∼80%). A previous case study suggested that non-binding aggregate formed in cell culture was the root cause of low Protein A step yield. In the current work, we selected five projects with the low Protein A yield issue to further illustrate this phenomenon. In all cases, existence of non-binding aggregates was confirmed by size-exclusion chromatography-high performance liquid chromatography (SEC-HPLC) analysis of Protein A load and flow-through. In addition, we demonstrated that aggregates failed to bind to Protein A resin mainly due to their large sizes, which prevented them from entering the resin beads. As the data suggested, SEC-HPLC analysis of Protein A load and flow-through, although not a standard procedure, can provide information that is critical for understanding the unexpected performance of Protein A chromatography in cases like those being presented here. Thus, SEC-HPLC analysis of Protein A load and flow-through is highly recommended for antibodies/Fc-fusions suffering from low Protein A yield.


Assuntos
Anticorpos Biespecíficos , Técnicas de Cultura de Células , Cromatografia Líquida de Alta Pressão , Cromatografia em Gel , Anticorpos Monoclonais/química , Anticorpos Biespecíficos/química , Proteína Estafilocócica A/química
4.
Crit Rev Food Sci Nutr ; : 1-21, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38993144

RESUMO

Quinoa (Chenopodium quinoa Willd) is widely regarded as a versatile pseudo-cereal native to the Andes Mountains in South America. It has gained global recognition as a superfood due to its rich nutritional profile. While quinoa grains are well-known, there is an undiscovered potential in quinoa greens, such as sprouts, leaves, and microgreens. These verdant parts of quinoa are rich in a diverse array of essential nutrients and bioactive compounds, including proteins, amino acids, bioactive proteins, peptides, polyphenols, and flavonoids. They have powerful antioxidant properties, combat cancer, and help prevent diabetes. Quinoa greens offer comparable or even superior benefits when compared to other sprouts and leafy greens, yet they have not gained widespread recognition. Limited research exists on the nutritional composition and biological activities of quinoa greens, underscoring the necessity for thorough systematic reviews in this field. This review paper aims to highlight the nutritional value, bioactivity, and health potential of quinoa greens, as well as explore their possibilities within the food sector. The goal is to generate interest within the research community and promote further exploration and wider utilization of quinoa greens in diets. This focus may lead to new opportunities for enhancing health and well-being through innovative dietary approaches.

5.
Fish Shellfish Immunol ; 149: 109532, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38579977

RESUMO

C-type lectins (CTLs) execute critical functions in multiple immune responses of crustaceans as a member of pattern recognition receptors (PRRs) family. In this study, a novel CTL was identified from the exoskeleton of the oriental river prawn Macrobrachium nipponense (MnLec3). The full-length cDNA of MnLec3 was 1150 bp with an open reading frame of 723 bp, encoding 240 amino acids. MnLec3 protein contained a signal peptide and one single carbohydrate-recognition domain (CRD). MnLec3 transcripts were widely distributed at the exoskeleton all over the body. Significant up-regulation of MnLec3 in exoskeleton after Aeromonas hydrophila challenged suggested the involvement of MnLec3 as well as the possible function of the exoskeleton in immune response. In vitro tests with recombinant MnLec3 protein (rMnLec3) manifested that it had polysaccharide binding activity, a wide spectrum of bacterial binding activity and agglutination activity only for tested Gram-negative bacteria (Escherichia coli, Vibrio anguillarum and A. hydrophila). Moreover, rMnLec3 significantly promoted phagocytic ability of hemocytes against A. hydrophila in vivo. What's more, MnLec3 interference remarkably impaired the survivability of the prawns when infected with A. hydrophila. Collectively, these results ascertained that MnLec3 derived from exoskeleton took an essential part in immune defense of the prawns against invading bacteria as a PRR.


Assuntos
Aeromonas hydrophila , Sequência de Aminoácidos , Proteínas de Artrópodes , Regulação da Expressão Gênica , Hemócitos , Imunidade Inata , Lectinas Tipo C , Palaemonidae , Fagocitose , Filogenia , Alinhamento de Sequência , Animais , Palaemonidae/imunologia , Palaemonidae/genética , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Lectinas Tipo C/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Proteínas de Artrópodes/química , Hemócitos/imunologia , Imunidade Inata/genética , Aeromonas hydrophila/fisiologia , Alinhamento de Sequência/veterinária , Regulação da Expressão Gênica/imunologia , Perfilação da Expressão Gênica/veterinária , Sequência de Bases , Exoesqueleto/imunologia , Exoesqueleto/química
6.
Inorg Chem ; 63(24): 11092-11101, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38843593

RESUMO

Black phosphorus (BP), a promising two-dimensional (2D) layered semiconductor material, has gained enormous attention due to its impressive properties over the past several years. Although plenty of methods have been developed to synthesize high-quality BP, most of the currently available BP materials still suffer from unsatisfactory crystallization, purity, and stability in air, hindering their practical application. A facile approach to synthesizing ultrahigh-quality single-crystal BP is of significance to shed light on the nature of 2D semiconductor materials and their massive application. In this work, we present the facile and efficient circulating vapor growth approach to growing bulk single-crystal BP. The as-grown BP material features high crystallinity and ultrahigh purity (higher than 99.999 at %), exceeding those of all the previously reported and some commercially available BP crystals. It also maintains excellent stability in air and water after 15 consecutive days of test. Moreover, the as-synthesized BP material features good thermal stability, oxidation resistance, and excellent electrical properties, as well. This study provides a new approach for the fabrication of ultrahigh-quality BP material and thus promotes its application.

7.
BMC Infect Dis ; 24(1): 770, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090540

RESUMO

BACKGROUND: The GeneXpert MTB/RIF (Xpert) assay is a widely used technology for detecting Mycobacterium tuberculosis (MTB) in clinical samples. However, the study on the failure of the Xpert assay during routine implementation and its potential solutions is limited. METHODS: We retrospectively analyzed the records of unsuccessful tests in the Xpert and the GeneXpert MTB/RIF Ultra (Ultra) assays between April 2017 and April 2021 at the Shanghai Public Health Clinical Center. To further investigate the effect of prolonged preprocessing on clinical sputum, an additional 120 sputum samples were collected for Xpert testing after 15 min, 3 h, and 6 h preprocessing. The analysis was performed by SPSS version 19.0 software. RESULTS: A total of 11,314 test records were analyzed, of which 268 (2.37%) had unsuccessful test results. Among these, 221 (1.95%) were reported as "Error", 43 (0.38%) as "Invalid", and 4 (0.04%) as "No result". The most common clinical specimen for Xpert tests was sputum, accounting for 114 (2.17%) unsuccessful tests. The failure rate of urine specimens was lower than that of sputum (OR = 0.12, 95% CI: 0.02-0.88, χ2 = 6.22, p = 0.021). In contrast, the failure rate of stool specimens was approximately twice as high as that of sputum (OR = 1.93, 95% CI: 1.09-3.40, χ2 = 5.35, p = 0.014). In the prolonged preprocessing experiment, 102 cases (85%) yielded consistent results in Xpert tests. Furthermore, 7 cases (5.83%) detected an increase in MTB load, 8 cases (6.67%) detected a decrease in MTB load, and 3 cases (2.5%) yielded incongruent results in MTB and rifampicin resistance detection. CONCLUSIONS: The primary cause of unsuccessful tests in the Xpert assay was reported as "Error". Despite varying failure rates depending on the samples, the Xpert assay can be applied to extrapulmonary samples. For paucibacillary specimens, retesting the remaining preprocessed mixture should be carefully considered.


Assuntos
Mycobacterium tuberculosis , Escarro , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Estudos Retrospectivos , China , Manejo de Espécimes/métodos , Técnicas de Diagnóstico Molecular/métodos , Tuberculose/diagnóstico , Tuberculose/microbiologia , Rifampina/farmacologia , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/microbiologia , Masculino , Feminino
8.
J Phys Chem A ; 128(42): 9201-9207, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39387815

RESUMO

Photoinduced intramolecular charge separation in a pyrene- and triarylamine-based donor-acceptor dyad was studied by polarization-dependent femtosecond time-resolved transient absorption (TA) spectroscopy in polar solvents. Photoexcitation forms an excited state with charge transfer (CT) character due to the intrinsic electronic coupling between the triarylamine and pyrene groups, resulting in ultrafast charge separation (CS) in polar solvents. TA measurements reveal a correlation between the rate of CS and solvation dynamics, which implies that solvation is involved in the CS reaction. In addition, polarization-dependent TA spectroscopy was devoted to tracking the ultrafast anisotropy evolution of the cationic absorption band, which is attributed to intramolecular torsional motion and is proposed to be coupled to diffusive orientational solvent modes. The results therefore reveal that the evolution of the CT state in the condensed phase is driven by solvation-coupled excited-state structural relaxation. In other words, intramolecular torsional motion is directly confirmed to be involved in the reaction coordinate of the CS reaction in a strongly coupled donor-acceptor dyad.

9.
Sensors (Basel) ; 24(10)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38794106

RESUMO

Road traffic safety facilities (TSFs) are of significant importance in the management and maintenance of traffic safety. The complexity and variety of TSFs make it challenging to detect them manually, which renders the work unsustainable. To achieve the objective of automatic TSF detection, a target detection dataset, designated TSF-CQU (TSF data collected by Chongqing University), was constructed based on images collected by a car recorder. This dataset comprises six types of TSFs and 8410 instance samples. A detection transformer with an improved denoising anchor box (DINO) was selected to construct a model that would be suitable for this scenario. For comparison purposes, Faster R-CNN (Region Convolutional Neural Network) and Yolov7 (You Only Look Once version 7) were employed. The DINO model demonstrated the highest performance on the TSF-CQU dataset, with a mean average precision (mAP) of 82.2%. All of the average precision (AP) values exceeded 0.8, except for streetlights (AP = 0.77) and rods (AP = 0.648). The DINO model exhibits minimal instances of erroneous recognition, which substantiates the efficacy of the contrastive denoising training approach. The DINO model rarely makes misjudgments, but a few missed detection.

10.
Sensors (Basel) ; 24(18)2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39338904

RESUMO

Unmanned aerial vehicles (UAVs) are effective tools for identifying road anomalies with limited detection coverage due to the discrete spatial distribution of roads. Despite computational, storage, and transmission challenges, existing detection algorithms can be improved to support this task with robustness and efficiency. In this study, the K-means clustering algorithm was used to calculate the best prior anchor boxes; Faster R-CNN (region-based convolutional neural network), YOLOX-s (You Only Look Once version X-small), YOLOv5-s, YOLOv7-tiny, YOLO-MobileNet, and YOLO-RDD models were built based on image data collected by UAVs. YOLO-MobileNet has the most lightweight model but performed worst in accuracy, but greatly reduces detection accuracy. YOLO-RDD (road distress detection) performed best with a mean average precision (mAP) of 0.701 above the Intersection over Union (IoU) value of 0.5 and achieved relatively high accuracy in detecting all four types of distress. The YOLO-RDD model most successfully detected potholes with an AP of 0.790. Significant or severe distresses were better identified, and minor cracks were relatively poorly identified. The YOLO-RDD model achieved an 85% computational reduction compared to YOLOv7-tiny while maintaining high detection accuracy.

11.
Molecules ; 29(6)2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38542867

RESUMO

Jieyu Pills (JYPs), a Chinese medicine consisting of 10 herbal elements, have displayed promising clinical effectiveness and low by-effects in the treatment of depression. Prior investigations mostly focused on elucidating the mechanism and therapeutic efficacy of JYPs. In our earlier study, we provided an analysis of the chemical composition, serum pharmacochemistry, and concentrations of the main bioactive chemicals found in JYPs. However, our precise understanding of the pharmacokinetics and metabolism remained vague. This study involved a comprehensive and meticulous examination of the pharmacokinetics of 13 bioactive compounds in JYPs. Using UPLC-Orbitrap Fusion MS, we analyzed the metabolic characteristics and established the pharmacokinetic parameters in both control rats and model rats with attention deficit hyperactivity disorder (ADHD) following oral administration of the drug. Before analysis, plasma samples that were collected at different time intervals after the administration underwent methanol pre-treatment with Puerarin used as the internal standard (IS) solution. Subsequently, the sample was chromatographed on a C18 column employing gradient elution. The mobile phase consisted of methanol solution containing 0.1% formic acid in water. The electrospray ionization source (ESI) was utilized for ionization, whereas the scanning mode employed was selected ion monitoring (SIM). The UPLC-Orbitrap Fusion MS method was subjected to a comprehensive validation process to assess its performance. The method demonstrated excellent linearity (r ≥ 0.9944), precise measurements (RSD < 8.78%), accurate results (RE: -7.88% to 8.98%), and appropriate extraction recoveries (87.83-102.23%). Additionally, the method exhibited minimal matrix effects (87.58-101.08%) and satisfactory stability (RSD: 1.52-12.42%). These results demonstrated adherence to the criteria for evaluating and determining biological material. The 13 bioactive compounds exhibited unique pharmacokinetic patterns in vivo. In control rats, all bioactive compounds except Ferulic acid exhibited linear pharmacokinetics within the dose ranges. In the ADHD model, the absorption rate and amount of most of the components were both observed to have increased. Essentially, this work is an important reference for examining the metabolism of JYPs and providing guidelines for clinical therapy.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Medicamentos de Ervas Chinesas , Ratos , Animais , Ratos Sprague-Dawley , Cromatografia Líquida de Alta Pressão/métodos , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Espectrometria de Massas em Tandem/métodos , Metanol , Medicamentos de Ervas Chinesas/análise , Reprodutibilidade dos Testes
12.
J Environ Sci (China) ; 142: 236-247, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38527889

RESUMO

The response patterns of microbial functional genes involved in biogeochemical cycles to cadaver decay is a central topic of recent environmental sciences. However, the response mechanisms and pathways of the functional genes associated with the carbon (C) and nitrogen (N) cycling to cadaveric substances such as cadaverine and putrescine remain unclear. This study explored the variation of functional genes associated with C fixation, C degradation and N cycling and their influencing factors under cadaverine, putrescine and mixed treatments. Our results showed only putrescine significantly increased the alpha diversity of C fixation genes, while reducing the alpha diversity of N cycling genes in sediment. For the C cycling, the mixed treatment significantly decreased the total abundance of reductive acetyl-CoA pathway genes (i.e., acsB and acsE) and lig gene linked to lignin degradation in water, while only significantly increasing the hydroxypropionate-hydroxybutylate cycle (i.e., accA) gene abundance in sediment. For the N cycling, mixed treatment significantly decreased the abundance of the nitrification (i.e., amoB), denitrification (i.e., nirS3) genes in water and the assimilation pathway gene (i.e., gdhA) in sediment. Environmental factors (i.e., total carbon and total nitrogen) were all negatively associated with the genes of C and N cycling. Therefore, cadaverine and putrescine exposure may inhibit the pathway in C fixation and N cycling, while promoting C degradation. These findings can offer some new insight for the management of amine pollution caused by animal cadavers.


Assuntos
Carbono , Putrescina , Humanos , Animais , Cadaverina , Água , Rios/química , Sedimentos Geológicos/química , Ciclo do Nitrogênio , Nitrogênio
13.
BMC Genomics ; 24(1): 447, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553575

RESUMO

BACKGROUND: Lonicera japonica Thunb. is widely used in traditional Chinese medicine. Medicinal L. japonica mainly consists of dried flower buds and partially opened flowers, thus flowers are an important quality indicator. MADS-box genes encode transcription factors that regulate flower development. However, little is known about these genes in L. japonica. RESULTS: In this study, 48 MADS-box genes were identified in L. japonica, including 20 Type-I genes (8 Mα, 2 Mß, and 10 Mγ) and 28 Type-II genes (26 MIKCc and 2 MIKC*). The Type-I and Type-II genes differed significantly in gene structure, conserved domains, protein structure, chromosomal distribution, phylogenesis, and expression pattern. Type-I genes had a simpler gene structure, lacked the K domain, had low protein structure conservation, were tandemly distributed on the chromosomes, had more frequent lineage-specific duplications, and were expressed at low levels. In contrast, Type-II genes had a more complex gene structure; contained conserved M, I, K, and C domains; had highly conserved protein structure; and were expressed at high levels throughout the flowering period. Eleven floral homeotic MADS-box genes that are orthologous to the proposed Arabidopsis ABCDE model of floral organ identity determination, were identified in L. japonica. By integrating expression pattern and protein interaction data for these genes, we developed a possible model for floral organ identity determination. CONCLUSION: This study genome-widely identified and characterized the MADS-box gene family in L. japonica. Eleven floral homeotic MADS-box genes were identified and a possible model for floral organ identity determination was also developed. This study contributes to our understanding of the MADS-box gene family and its possible involvement in floral organ development in L. japonica.


Assuntos
Genoma de Planta , Lonicera , Lonicera/genética , Lonicera/metabolismo , Proteínas de Domínio MADS/metabolismo , Fatores de Transcrição/metabolismo , Família Multigênica , Filogenia , Regulação da Expressão Gênica de Plantas , Flores , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
14.
Small ; 19(4): e2205716, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36437045

RESUMO

Multifunctional thermal management materials with highly efficient electromagnetic wave (EMW) absorption performance are urgently required to tackle the heat dissipation and electromagnetic interference issues of high integrated electronics. However, the high thermal conductivity (λ) and outstanding EMW absorption performance are often incompatible with each other in a single material. Herein, a through-thickness arrayed NiCo2 O4 /graphene oxide/carbon fibers (NiCO@CFs) elastomer with integrated functionalities of high thermal conductivity, highly efficient EMW absorption, and excellent compressibility is reported. The NiCO@CFs elastomer realizes a high out-of-plane thermal conductivity of 15.55 W m-1  K-1 , due to the through-thickness vertically aligned CFs framework. Moreover, the unique horizontal segregated magnetic network effectively reduces the electrical contact between the CFs, which significantly enhances impedance matching of NiCO@CFs elastomer. As a result, the vertically arrayed NiCO@CFs elastomer synchronously exhibits ultrabroad effective absorption bandwidth of 8.25 GHz (9.75-18 GHz) at a thickness of 2.4 mm, good impedance matching, and a minimum reflection loss (RLmin ) of -55.15 dB. Given these outstanding findings, the multifunctional arrayed NiCO@CFs elastomer opens an avenue for applications in EMW absorption and thermal management. This strategy of constructing thermal/electrical/mechanical pathways provides a promising way for the high-performance multifunctional materials in electronic devices.

15.
Langmuir ; 39(48): 16975-16985, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-37994525

RESUMO

In the past decades, remarkable progress has been made in the field of human-machine interaction. The need for accurate sensing devices with satisfactory user experiences has propelled the development of flexible, stretchable, biocompatible, and imperceptible hydrogel-based interfaces. These innovative interfaces facilitate direct interactions between humans and machines while receiving detected input signals from sensors and giving output commands to controllers, thus motivating accurate real-time responsiveness. This Perspective discusses the sensing mechanisms for the two categories of hydrogel-based sensors and summarizes the recent progress in the development of different representations of human-machine interactions, including intelligent identification, information secrecy, interactive control, and virtual reality and augmented reality technologies. The advantages of hydrogel-based systems over conventionally used rigid electrical components are explicitly discussed. The conclusion provides a perspective on current challenges and outlines a future roadmap for the realization of state-of-the-art hydrogel-based smart systems.


Assuntos
Hidrogéis , Dispositivos Eletrônicos Vestíveis , Humanos
16.
Protein Expr Purif ; 210: 106297, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37209930

RESUMO

In downstream processing of protein therapeutics, ion exchange (IEX) chromatography is a powerful tool for removing byproducts whose isoelectric point (pI) is appreciably different from that of the product. Although in theory for a given case cation exchange (CEX) and anion exchange (AEX) chromatography should be equally effective for separation, in reality they may show different effectiveness. In the current work, with a case study, we demonstrated that AEX is more effective than CEX chromatography at removing the associated byproducts. In addition, we screened AEX resins and loading conditions to achieve best separation. Finally, we demonstrated that effective separation was achieved with the selected resin/condition, and chromatography performance was comparable between runs conducted at low and high load densities, suggesting that the developed process was relatively robust. The procedure described in this work can be used as a general approach for selecting resin and loading condition that allow for effective and robust removal of byproduct that binds weaker than the product to the selected type of column.


Assuntos
Resinas de Troca Aniônica , Cromatografia por Troca Iônica/métodos , Resinas de Troca Aniônica/química , Ânions , Cátions/química
17.
Phys Chem Chem Phys ; 25(36): 24386-24394, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37283300

RESUMO

Boron-dipyrromethene (BODIPY) derivatives are prospective organic-based triplet photosensitizers. Since the triplet generation yield of the parent BODIPY is low, heavy atoms are widely used to improve the triplet yield. However, the dimerization of BODIPYs can also significantly improve their ability to produce triplets. Through a comparative study of the triplet formation dynamics of two heavy-atom-free orthogonal covalent BODIPY heterodimers that differ in their dihedral angles, we have demonstrated that the mechanism of spin-orbit charge-transfer intersystem crossing (SOCT-ISC) promotes the triplet generation of BODIPY heterodimers in solution. Different from the general understanding of SOCT-ISC, the heterodimer with a smaller dihedral angle and low structural rigidity showed better triplet generation due to (a) the stronger inter-chromophoric interaction in the heterodimer, which promoted the formation of a solvent-stabilized charge-transfer (CT) state, (b) the more favorable energy level alignment with sizeable spin-orbit coupling strength, and (c) the balance between the stabilized singlet CT state and limited direct charge recombination to the ground state in a weakly polar solvent. The complete spectral characterization of the triplet formation dynamics clarified the SOCT-ISC mechanism and important factors affecting the triplet generation in BODIPY heterodimers.

18.
Environ Res ; 225: 115653, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36898422

RESUMO

Corpse decomposition is of great significance to the carbon cycle of natural ecosystem. Carbon fixation is a carbon conversion process that converts carbon dioxide into organic carbon, which greatly contributes to carbon emission reduction. However, the effects of wild animal carcass decay on carbon-fixing microbes in grassland soil environment are still unknown. In this research, thirty wild mammal (Ochotona curzoniae) corpses were placed on alpine meadow soil to study the carbon storage and carbon-fixing microbiota succession for a 94-day decomposition using next-generation sequencing. Our results revealed that 1) the concentration of total carbon increased approximately 2.24-11.22% in the corpse group. 2) Several carbon-fixing bacterial species (Calothrix parietina, Ancylobacter rudongensis, Rhodopseudomonas palustris) may predict the concentration of total carbon. 3) Animal cadaver degradation caused the differentiation of carbon-fixing microbiota structures during succession and made the medium-stage networks of carbon-fixing microbes more complicated. 4) The temporal turnover rate in the experimental groups was higher than that in the control groups, indicating a quick change of gravesoil carbon-fixing microbiota. 5) The deterministic process dominates the assembly mechanism of experimental groups (ranging from 53.42% to 94.94%), which reflects that the carbon-fixing microbial community in gravesoil can be regulated. Under global climate change, this study provides a new perspective for understanding the effects of wild animal carcass decay on soil carbon storage and carbon-fixing microbes.


Assuntos
Pradaria , Microbiota , Animais , Solo/química , Microbiologia do Solo , Cadáver , Mamíferos
19.
Cell Mol Life Sci ; 79(5): 224, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35389112

RESUMO

BACKGROUND: Hematoma leads to progressive neurological deficits and poor outcomes after intracerebral hemorrhage (ICH). Early clearance of hematoma is widely recognized as an essential treatment to limit the damage and improve the clinical prognosis. CD163, alias hemoglobin (Hb) scavenger receptor on microglia, plays a pivotal role in hematoma absorption, but CD163 on neurons permits Hb uptake and results in neurotoxicity. In this study, we focus on how to specially promote microglial but not neuronal CD163 mediated-Hb uptake and hematoma absorption. METHODS: RNA sequencing was used to explore the potential molecules involved in ICH progression, and hematoma was detected by magnetic resonance imaging (MRI). Western blot and immunofluorescence were used to evaluate the expression and location of fractalkine (FKN) after ICH. Erythrophagocytosis assay was performed to study the specific mechanism of action of FKN in hematoma clearance. Small interfering RNA (siRNA) transfection was used to explore the effect of peroxisome proliferator-activated receptor-γ (PPAR-γ) on hematoma absorption. Enzyme-linked immunosorbent assay (ELISA) was used to determine the serum FKN concentration in ICH patients. RESULTS: FKN was found to be significantly increased around the hematoma in a mouse model after ICH. With its unique receptor CX3CR1 in microglia, FKN significantly decreased the hematoma size and Hb content, and improved neurological deficits in vivo. Further, FKN could enhance erythrophagocytosis of microglia in vitro via the CD163/ hemeoxygenase-1 (HO-1) axis, while AZD8797 (a specific CX3CR1 inhibitor) reversed this effect. Moreover, PPAR-γ was found to mediate the increase in the CD163/HO-1 axis expression and erythrophagocytosis induced by FKN in microglia. Of note, a higher serum FKN level was found to be associated with better hematoma resolution in ICH patients. CONCLUSIONS: We systematically identified that FKN may be a potential therapeutic target to improve hematoma absorption and we shed light on ICH treatment.


Assuntos
Quimiocina CX3CL1 , Microglia , Animais , Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/patologia , Quimiocina CX3CL1/metabolismo , Hematoma/tratamento farmacológico , Hematoma/metabolismo , Humanos , Camundongos , Microglia/metabolismo , Neurônios/metabolismo , PPAR gama/metabolismo , Receptores de Superfície Celular
20.
Neural Plast ; 2023: 5545205, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37609123

RESUMO

Hyperoside (Hyp), a kind of Chinese herbal medicine, exerts multiple therapeutic effects on many diseases. However, the role and mechanisms of Hyp in vascular pathophysiology in ischemic stroke need to be further established. The study aimed to investigate the role of (large-conductance Ca2+-activated K+) BK channels on the vasoprotection of Hyp against cerebral ischemia and reperfusion (I/R) injury in rats. The concentration gradient of Hyp was pretreated in both the middle cerebral artery occlusion and reperfusion model and oxygen-glucose deprivation/reoxygenation (OGD/R) model of primary vascular smooth muscle cells (VSMCs) in rats. A series of indicators were detected, including neurological deficit score, infarct volume, malondialdehyde (MDA), superoxide dismutase (SOD), cerebral blood flow (CBF), cell viability, membrane potential, and BK channels α- and ß1-subunits expression. The results showed that Hyp significantly reduced infarct volume and ameliorated neurological dysfunction in I/R-injured rats. Besides, the effects of I/R-induced reduction of BK channels α- and ß1-subunits expression were significantly reversed by Hyp in endothelial-denudated cerebral basilar arteries. Furthermore, the protective effect against I/R-induced increases of MDA and reduction of SOD as well as CBF induced by Hyp was significantly reversed by iberiotoxin (IbTX). In OGD/R-injured VSMCs, downregulated cellular viability and BK channels ß1-subunits expression were remarkably reversed by Hyp. However, neither OGD/R nor Hyp affected BK channels α-subunits expression, and Hyp failed to induced hyperpolarization of VSMCs. Moreover, the protective effect against OGD/R-induced reduction of cell viability and SOD level and increases of MDA production induced by Hyp was significantly reversed by IbTX in VSMCs. The study indicates that Hyp has the therapeutic potential to improve vascular outcomes, and the mechanism is associated with suppressing oxidative stress and improving CBF through upregulating BK channels.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Animais , Ratos , Canais de Potássio Ativados por Cálcio de Condutância Alta , Traumatismo por Reperfusão/tratamento farmacológico , Superóxido Dismutase , Isquemia Encefálica/tratamento farmacológico
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