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2.
J Colloid Interface Sci ; 607(Pt 2): 1928-1935, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34695741

RESUMO

PtNi alloy nanoparticles display promising catalytic activity for oxygen reduction reaction (ORR), while the Ostwald ripening of particles and the dissolution/migration of surface atoms greatly affect its stability thus restricting the application. Herein, the WOx-surface modified PtNi alloy nanowires (WOx-PtNi NWs) exhibiting enhanced ORR catalytic property is reported, which has high aspect ratio with the diameter of only 2 âˆ¼ 3 nm. It is found that the WOx-PtNi NWs shows a volcano relationship between the ORR activity and the content of WOx. The WOx-(0.25)-PtNi NWs has the best performance among all the synthesized catalysts. Its mass activity (0.85 A mg-1Pt) is reduced by only 23.89% after 30k cycles durability test, which is much more stable than that of PtNi NWs (0.33 A mg-1Pt, 45.94%) and Pt/C (0.14 A mg-1Pt, 57.79%). Hence this work achieves an effective regulation of the ORR activity for PtNi alloy NWs by the synergistic effect of WOx on Pt.

3.
Mol Cancer ; 20(1): 150, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34798898

RESUMO

BACKGROUND: Accumulation of Foxp3+ regulatory T (Treg) cells in the tumor often represents an important mechanism for cancer immune evasion and a critical barrier to anti-tumor immunity and immunotherapy. Many tumor-infiltrating Treg cells display an activated phenotype and express the transcription factor Blimp1. However, the specific impact of these Blimp1+ Treg cells and their follicular regulatory T (TFR) cell subset on tumor and the underlying mechanisms of action are not yet well-explored. METHODS: Various transplantable tumor models were established in immunocompetent wild-type mice and mice with a Foxp3-specific ablation of Blimp1. Tumor specimens from patients with metastatic melanoma and TCGA datasets were analyzed to support the potential role of Treg and TFR cells in tumor immunity. In vitro culture assays and in vivo adoptive transfer assays were used to understand how Treg, TFR cells and antibody responses influence tumor control. RNA sequencing and NanoString analysis were performed to reveal the transcriptome of tumor-infiltrating Treg cells and tumor cells, respectively. Finally, the therapeutic effects of anti-PD-1 treatment combined with the disruption of Blimp1+ Treg activity were evaluated. RESULTS: Blimp1+ Treg and TFR cells were enriched in the tumors, and higher tumoral TFR signatures indicated increased risk of melanoma metastasis. Deletion of Blimp1 in Treg cells resulted in impaired suppressive activity and a reprogramming into effector T-cells, which were largely restricted to the tumor-infiltrating Treg population. This destabilization combined with increased anti-tumor effector cellular responses, follicular helper T-cell expansion, enhanced tumoral IgE deposition and activation of macrophages secondary to dysregulated TFR cells, remodeled the tumor microenvironment and delayed tumor growth. The increased tumor immunogenicity with MHC upregulation improved response to anti-PD-1 blockade. Mechanistically, Blimp1 enforced intratumoral Treg cells with a unique transcriptional program dependent on Eomesodermin (Eomes) expression; deletion of Eomes in Blimp1-deficient Treg cells restored tumor growth and attenuated anti-tumor immunity. CONCLUSIONS: These findings revealed Blimp1 as a new critical regulator of tumor-infiltrating Treg cells and a potential target for modulating Treg activity to treat cancer. Our study has also revealed two FCERIA-containing immune signatures as promising diagnostic or prognostic markers for melanoma patients.

4.
Med Sci Monit ; 27: e933443, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34799547

RESUMO

BACKGROUND Pancreatic adenocarcinoma (PAAD) is one of the deadliest types of cancer. In the early stages, patients often have atypical symptoms, making diagnosis difficult. The prognosis of diagnosed patients is very poor and treating PAAD is challenging. Therefore, determining reliable risk factors related to PAAD development is critical for improving patient prognosis. E2F family transcription factors (TFs) are essential regulators of DNA synthesis and cell cycle progression in eukaryotic cells, and they have been identified as prognostic biomarkers associated with multiple cancer types. However, further research is necessary to establish the prognostic relevance of these TFs in PAAD patients. MATERIAL AND METHODS We assessed PAAD patient transcriptional and outcome data using the TIMER, ONCOMINE, STRING, GEPIA, cBioPortal, Kaplan-Meier Plotter, GSCALite, and starBase databases. RESULTS PAAD tumor tissues exhibited increased expression of E2F1/3/5/7/8 relative to that in normal tissues, while the expression of E2F2/3/6/8 was associated with a more advanced tumor stage. Survival analyses indicated that PAAD patients expressing higher levels of E2F1/2/3/7/8 exhibited shorter overall survival (OS) and disease-free survival (DFS) than patients expressing lower levels of these TFs. In addition, E2F4 and E2F6 overexpression was associated with poorer DFS and OS, respectively. We also found that the expression of E2Fs was significantly correlated with immune infiltrates, including CD8+ T cells, CD4+ T cells, B cells, dendritic cells, neutrophils, and macrophages. CONCLUSIONS Our study may provide new insights into the optimal choice of immunotherapy and promising novel targets for therapeutic intervention in PAAD patients.

5.
Risk Manag Healthc Policy ; 14: 4393-4399, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34729027

RESUMO

Background and Aim: Relevant studies show that population migration has a great impact on the early spread of infectious diseases. Therefore, it is important to explore whether there is an explicit relationship between population migration and the number of confirmed cases for the control of the COVID-19 epidemic. This paper mainly explores the impact of population migration on early COVID-19 transmission, and establishes a predictive nonlinear mathematical model to predict the number of early cases. Methods: Data of confirmed cases were sourced from the official website of the Municipal Health Committee, and the proportions of migration from Wuhan to other cities were sourced from the Baidu data platform. The data of confirmed cases and the migration proportions of 14 cities in Hubei Province were collected, the COVID-19 cases study period was determined as 10 days based on the third quartile of the interval of the incubation period, and a non-linear mathematical model was constructed to clarify the relationship between the migration proportion and the number of confirmed COVID-19 cases. Finally, eight typical regions were selected to verify the accuracy of the model. Results: The daily population migration rates and the growth curves of the number of confirmed cases in the 14 cities were basically consistent, and Pearson's correlation coefficient was 0.91. The specific mathematical expression of 14 regions is . In each of the fourteen cities, The nonlinear exponential model structure is as follows:. It was found that the R 2 values of the fitted mathematical model were greater than 0.8 in all studied regions, excluding Suizhou (p < 0.05). The established mathematical model was used to fit eight regions in China, and the correlations between the predicted and actual numbers of confirmed cases were greater than 0.9, excluding that of Hebei Province (0.82). Conclusion: The study found that population migration has a positive and significant impact on the spread of COVID-19. Modeling COVID-19 risk may be a useful strategy for directing public health surveillance and interventions. Restricting the migration of the population is of great significance to the joint prevention and control of the pandemic worldwide.

6.
J Genet Genomics ; 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34757038

RESUMO

Melastomataceae have abundant morphological diversity with high economic and ornamental merit in Myrtales. The phylogenetic position of Myrtales is still contested. Here, we report the first chromosome-level genome assembly of Melastoma dodecandrum in Melastomataceae. The assembled genome size was 299.81 Mb with a contig N50 value of 3.00 Mb. Genome evolution analysis indicated that M. dodecandrum, Eucalyptus grandis and Punica granatum were clustered into a clade of Myrtales and formed a sister group with the ancestor of fabids and malvids. We found that M. dodecandrum experienced four whole-genome polyploidization events: the ancient event was shared with most eudicots, one event was shared with Myrtales, and the other two events were unique to M. dodecandrum. Moreover, we identified MADS-box genes and found that the AP1-like genes expanded, and AP3-like genes might have undergone subfunctionalization. We found that the SUAR63-like genes and AG-like genes showed different expression patterns in stamens, which may be associated with heteranthery. In addition, we found that LAZY1-like genes were involved in the negative regulation of stem branching development, which may be related to its creeping features. Our study sheds new light on the evolution of Melastomataceae and Myrtales, which provides a comprehensive genetic resource for future research.

7.
Front Psychiatry ; 12: 720833, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34733186

RESUMO

Objective: To explore the effects of using RPE exercise intensity monitoring methods and 12-week mid- and low-intensity team aerobic training on anxiety, depression and sleep quality of depressed middle school students after the COVID-19 epidemic. Methods: All study participants were all from a boarding middle school in Chongqing, China. All study participants were screened by the self-rating depression scale and reached the diagnostic criteria for depression. The study subjects were divided into a control group (N = 35) and an exercise group (N = 34). The exercise group performed 30-min night aerobic running four times a week. Use the Borg 6-20 rating of perceived exertion scale (RPE) as a monitoring tool for exercise intensity, and control the exercise intensity at RPE = 11-14. And the control group studied and lived normally. The experiment lasted 12 weeks in total. After the experiment, there were 34 people in the control group and 23 people in the exercise group. The subjects' anxiety, depression and Pittsburgh sleep quality were scored before and after the experiment. Results: After intervention, the depression index (p < 0.01) of the exercise group was significantly lower than that of the control group. Conclusion: Using the RPE exercise intensity monitoring method for 12 weeks of mid- and low-intensity team aerobic training can improve the depressive symptoms of depressed middle school students, and it is beneficial to improve the students' mental health.

8.
Opt Express ; 29(17): 26876-26893, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34615114

RESUMO

The binocular stereo matching method based on deep learning has limited cross-domain generalization ability, and it is a tricky problem to obtain a large amount of data from real scenes for training. The most advanced stereo matching network is difficult to apply to new real scenes. In this paper, we propose a real-scene stereo matching method based on a convolutional neural network and computer graphics. A virtual binocular imaging system is constructed by introducing graphics software, and a high-quality semi-synthetic dataset close to the texture characteristics of the real scene is constructed for training the network. A feature standardization layer is embedded in the feature extraction module of the proposed network to further reduce the feature space difference between semi-synthetic data and real scene data. Three small 4D cost volumes are constructed to replace one large 4D cost volume, which reduces GPU memory consumption and improves the matching performance of the network. The experimental results show that compared with the traditional stereo matching method, the matching accuracy of the proposed method is significantly improved by about 60%. Compared with other learning-based methods, the matching accuracy is increased by about 30%, the matching speed is increased by 38%, and it has good robustness to the interference of defocus blur and Gaussian noise.

9.
J Hazard Mater ; : 127411, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34629198

RESUMO

The excessive use of carbaryl has resulted in the risk of its exposure. In this study, we isolated six nanobodies (Nbs) from a camelid phage display library against the biomarker of carbaryl, 1-naphthol (1-NAP). Owing to its characteristics of easy genetic modifications, we produced a nanobody-alkaline phosphatase (Nb-CC4-ALP) fusion protein with good stability. A dual-emission system based ratiometric fluoroimmunoassay (RFIA) for quick and highly sensitive determination of 1-NAP was developed. Silicon nanoparticles (SiNPs) was used as an internal reference and for aggregation-induced emission enhancement (AIEE) of gold nanoclusters (AuNCs), while AuNCs could be quenched by MnO2 via oxidation. In the presence of ALP, ascorbic acid phosphate (AAP) can be transformed into ascorbic acid (AA), the later can etch MnO2 to recover the fluorescence of the AuNCs. Based on optimal conditions, the proposed assay showed 220-fold sensitivity improvement in comparison with conventional monoclonal antibody-based ELISA. The recovery test of urine samples and the validation by standard HPLC-FLD demonstrated the proposed assay was an ideal tool for screening 1-NAP and provided technical support for the monitoring of carbaryl exposure.

10.
Mitochondrial DNA B Resour ; 6(11): 3207-3208, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34676291

RESUMO

Tripsacum laxum (Guatemalan grass) is a perennial fodder grasses, which is commonly growing in large parts of Africa for a source of livestock feed. It has a high economic value as a forage. In this study, we obtained a complete chloroplast genome of T. laxum by Illumina sequencing. The results showed a circular genome of 140,556 bp, including the large single copy region (LSC, 82,939 bp), the small single-copy region (SSC, 12,573 bp), and a pair of 22,522 bp inverted repeat regions (IRs). The circular genome contained 120 genes, including 74 protein-coding genes, eight ribosomal RNA genes and 38 tRNA genes. Evolutionary relationship analysis indicates that T. laxum is more closely related to previously reported T. dactyloides.

11.
ACS Nano ; 15(10): 16729-16737, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34605638

RESUMO

Ultraviolet photodetectors (UVPDs) based on wide band gap semiconductors (WBSs) are important for various civil and military applications. However, the relatively harsh preparation conditions and the high cost are unfavorable for commercialization. In this work, we proposed a non-WBS UVPD by using a silicon nanowire (SiNW) array with a diameter of 45 nm as building blocks. Device analysis revealed that the small diameter SiNW array covered with monolayer graphene was sensitive to UV light but insensitive to both visible and infrared light illumination, with a typical rejection ratio of 25. Specifically, the responsivity, specific detectivity, and external quantum efficiency under 365 nm illumination were estimated to be 0.151 A/W, 1.37 × 1012 Jones, and 62%, respectively, which are comparable to or even better than other WBS UVPDs. Such an abnormal photoelectrical characteristic is related to the HE1m leaky mode resonance (LMR), which is able to shift the peak absorption spectrum from near-infrared to UV regions. It is also revealed that this LMR is highly dependent on the diameter and the period of the SiNW array. These results show narrow band gap semiconductor nanostructures as promising building blocks for the assembly of sensitive UV photodetectors, which are very important for various optoelectronic devices and systems.

12.
Front Pharmacol ; 12: 754175, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603063

RESUMO

Vitiligo is a complex disorder characterized by the loss of pigment in the skin. The current therapeutic strategies are limited. The identification of novel drug targets and candidates is highly challenging for vitiligo. Here we proposed a systematic framework to discover potential therapeutic targets, and further explore the underlying mechanism of kaempferide, one of major ingredients from Vernonia anthelmintica (L.) willd, for vitiligo. By collecting transcriptome and protein-protein interactome data, the combination of random forest (RF) and greedy articulation points removal (GAPR) methods was used to discover potential therapeutic targets for vitiligo. The results showed that the RF model performed well with AUC (area under the receiver operating characteristic curve) = 0.926, and led to prioritization of 722 important transcriptomic features. Then, network analysis revealed that 44 articulation proteins in vitiligo network were considered as potential therapeutic targets by the GAPR method. Finally, through integrating the above results and proteomic profiling of kaempferide, the multi-target strategy for vitiligo was dissected, including 1) the suppression of the p38 MAPK signaling pathway by inhibiting CDK1 and PBK, and 2) the modulation of cellular redox homeostasis, especially the TXN and GSH antioxidant systems, for the purpose of melanogenesis. Meanwhile, this strategy may offer a novel perspective to discover drug candidates for vitiligo. Thus, the framework would be a useful tool to discover potential therapeutic strategies and drug candidates for complex diseases.

13.
Environ Res ; : 112244, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34688645

RESUMO

Chemical fertilizer is gaining increasing attention and has been the center of much research which indicating complex beneficial and harmful effects. Chemical fertilizer might cause some environmental hazards to the biosphere, especially in the agricultural ecosystem. The application of silicon (Si) fertilizer in agriculture has been proved to be able to create good economic and environmental benefits. Si is the second most abundant earth crust element. Si fertilizer improves soil quality and alleviates biotic and abiotic crop stress. It is of great significance to understand the function of Si fertilizer in agricultural utilization and environmental remediation. This paper reviews the Si-based fertilizer in farmland use and summarizes prior research relevant with characterization, soil quality improvement, and pollution remediation effects. Its use in agriculture enhances plant silicon uptake, mediates plant salt and drought stress and remediates heavy metals such as Al, As, Cd, Cu, Zn and Cr. This article also summarizes the detoxification mechanism of silicon and its effects on plant physiological activity such as photosynthesis and transpiration. Fertilizer materials and crop fertilizer management were also considered. Foliar spraying is an effective method to improve crop growth and yield and reduce biotic or abiotic stress. Silicon nanoparticle material provides potential with great potential and prospects. More investigation and research are prospected to better understand how silicon impacts the environment and whether it is a beneficial additive.

14.
Front Plant Sci ; 12: 716784, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539710

RESUMO

The stomatal index of the leaf is the ratio of the number of stomata to the total number of stomata and epidermal cells. Comparing with the stomatal density, the stomatal index is relatively constant in environmental conditions and the age of the leaf and, therefore, of diagnostic characteristics for a given genotype or species. Traditional assessment methods involve manual counting of the number of stomata and epidermal cells in microphotographs, which is labor-intensive and time-consuming. Although several automatic measurement algorithms of stomatal density have been proposed, no stomatal index pipelines are currently available. The main aim of this research is to develop an automated stomatal index measurement pipeline. The proposed method employed Faster regions with convolutional neural networks (R-CNN) and U-Net and image-processing techniques to count stomata and epidermal cells, and subsequently calculate the stomatal index. To improve the labeling speed, a semi-automatic strategy was employed for epidermal cell annotation in each micrograph. Benchmarking the pipeline on 1,000 microscopic images of leaf epidermis in the wheat dataset (Triticum aestivum L.), the average counting accuracies of 98.03 and 95.03% for stomata and epidermal cells, respectively, and the final measurement accuracy of the stomatal index of 95.35% was achieved. R 2 values between automatic and manual measurement of stomata, epidermal cells, and stomatal index were 0.995, 0.983, and 0.895, respectively. The average running time (ART) for the entire pipeline could be as short as 0.32 s per microphotograph. The proposed pipeline also achieved a good transferability on the other families of the plant using transfer learning, with the mean counting accuracies of 94.36 and 91.13% for stomata and epidermal cells and the stomatal index accuracy of 89.38% in seven families of the plant. The pipeline is an automatic, rapid, and accurate tool for the stomatal index measurement, enabling high-throughput phenotyping, and facilitating further understanding of the stomatal and epidermal development for the plant physiology community. To the best of our knowledge, this is the first deep learning-based microphotograph analysis pipeline for stomatal index assessment.

15.
J Food Biochem ; : e13932, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34528276

RESUMO

The purpose of this study was to explore the hypouricemic effect in hyperuricemia mice of triterpenoid acids from Inonotus obliquus (TAIO), and decipher of the underlying xanthine oxidase inhibitory mechanism. Measurement of xanthine oxidase (XO) inhibitory activity was assayed. Organ indexes and serum biochemical indicators were measured in potassium oxonate-induced hyperuricemia mice. Studies showed that TAIO had the strong inhibitory effect on XO activity, and its inhibition type was mixed and reversible. In vivo, TAIO decreased efficiently uric acid level, hepatic XO, serum blood urea nitrogen activities in hyperuricemia mice. Indicating that TAIO may ameliorate kidney damage and relieve inflammation in hyperuricemic mice, and had the inhibitory effect on XO activity. Furthermore, eight triterpenoids were identified by Ultra performance liquid chromatography electrospray quadrupole time of flight mass spectrometry. These findings proved that triterpenoids from Inonotus obliquus would have potential biological characteristics and effect on controlling hyperuricemia and gout as an active supplement. PRACTICAL APPLICATIONS: There are a large amount of evidence indicating that hyperuricemia and gout are related to the hypertension and obesity. And gout and hyperuricemia are also possible connection with cardiovascular disease and metabolic syndrome. Currently, xanthine oxidase is the target of many kinds of chemical drugs at present, but the therapeutic drugs used in clinical medicine will produce more or less side effects. Therefore, the aim of this study was to explore the material basis of effective substances for reducing uric acid in Inonotus obliquus and to evaluate its effect. This study can provide a promising application of Inonotus obliquus in the fields of functional foods or medicines for gout and hyperuricemia.

16.
ACS Appl Mater Interfaces ; 13(36): 43273-43281, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34469096

RESUMO

In this study, we present a wavelength sensor that is capable of distinguishing the spectrum in the range from ultraviolet (UV) to near-infrared (NIR) light. The filterless device is composed of two horizontally stacking PdSe2/20 µm Si/PdSe2 heterojunction photodetectors with a photovoltaic (PV) behavior, which makes it possible for the device to work at 0 bias voltage. Due to the relatively small thickness of Si and the wavelength-dependent absorption coefficient, the two PdSe2/20 µm Si/PdSe2 photodetectors according to theoretical simulation display a sharp contrast in distribution of the photoabsorption rate. As a result, the photocurrents of both photodetectors evolve in completely different ways with increasing wavelengths, leading to a monotonic decrease in the photocurrent ratio from 6800 to 22 when the wavelength gradually increases from 265 to 1050 nm. The corresponding relationship between both the photocurrent ratio and wavelength can be easily described by the monotonic function, which can help to precisely determine the wavelength in the range from 265 to 1050 nm, with an average relative error less than ±1.6%. It is also revealed that by slightly revising the monotonic function, the wavelength in other different temperatures can also be estimated.

18.
Bioresour Technol ; 342: 125937, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34543820

RESUMO

This research explored the influence of distillers' grains amendment on the humification performance and microbial communities during rice straw composting. The composition of dissolved organic matter and maturity index were analyzed by the fluorescence excitation emission matrix spectroscopy and parallel factor analysis. High-throughput sequencing and redundancy analysis were employed for revealing the structure dynamics for microbial community and their shaping factors, respectively. Results indicated that addition of distillers' grains effectively increased the microbial activity, which was beneficial to the organic matter degradation and nitrogen conservation. Microbial community structures were significantly changed with different amendment strategies. Nitrate, water soluble carbon, organic matter, ammonium were the key parameters influencing the variation of bacterial community in different treatments. Water soluble carbon significantly affected the dominant fungal community dynamics. These results showed that addition of distillers' grains effectively improved the nutritional status and changed the microbial communities during rice straw composting.

19.
J Agric Food Chem ; 69(40): 11743-11752, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34583509

RESUMO

Mycotoxins are toxic contaminants in foods and feeds that are naturally occurring and largely unavoidable. Determining their contents in these products is essential to protect humans from harm. Immunoassays of mycotoxins have been well-established because they are fast, sensitive, simple, and cost-effective. However, a major limitation of immunoassays is the requirement of toxic mycotoxins as competing antigens, standards, or competing tracers. Mimotopes are peptides or proteins that can specifically bind to antibodies and compete with analytes for binding sites by mimicking antigenic epitopes. They can be employed as substitutes for competing antigens, standards, or competing tracers to avoid use of mycotoxins. This review summarizes the production and functionalization of the two main kinds of mimotopes, mimic peptides and anti-idiotypic antibodies (Ab2), and their applications in rapid analysis of mycotoxins.


Assuntos
Micotoxinas , Antígenos , Epitopos , Humanos , Imunoensaio , Peptídeos
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