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1.
Artículo en Inglés | MEDLINE | ID: mdl-38589588

RESUMEN

In the context of increasingly severe global climate change, finding effective carbon emission reduction strategies has become key to mitigating climate change. Environmental Protection Tax (EPT), as a widely recognized method, effectively promotes climate change mitigation by encouraging emission reduction behaviors and promoting the application of clean technologies. Based on data from 282 cities in China, this paper takes the official implementation of the EPT in 2018 as the policy impact and the cities with increased tax rates for air taxable pollutants as the treatment group and uses DID model to systematically demonstrate the relationship between the implementation of the EPT and carbon intensity (CI) and further explores the possible pollutant emissions and green innovation mediating effects. The findings show that (1) the implementation of EPT can effectively reduce CI by about 4.75%, and this conclusion still holds after considering the robustness of variable selection bias, elimination of other normal effects, policy setting time bias, and self-selection bias. (2) The implementation of EPT can reduce CI by reducing pollutant emissions and improving the level of green innovation. (3) There is obvious regional heterogeneity in the carbon reduction effect of EPT, and the implementation of EPT has a more significant effect on CI in medium-tax areas, low environmental concern areas, general cities, and eastern regions. This paper not only provides a new analytical perspective for systematically understanding the carbon emission reduction effect of EPT but also provides policy insights for promoting regional green transformation and advancing carbon peak carbon neutralization.

2.
Sci Adv ; 10(10): eadl1122, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38446892

RESUMEN

Coxsackievirus B (CVB) infection of pancreatic ß cells is associated with ß cell autoimmunity and type 1 diabetes. We investigated how CVB affects human ß cells and anti-CVB T cell responses. ß cells were efficiently infected by CVB in vitro, down-regulated human leukocyte antigen (HLA) class I, and presented few, selected HLA-bound viral peptides. Circulating CD8+ T cells from CVB-seropositive individuals recognized a fraction of these peptides; only another subfraction was targeted by effector/memory T cells that expressed exhaustion marker PD-1. T cells recognizing a CVB epitope cross-reacted with ß cell antigen GAD. Infected ß cells, which formed filopodia to propagate infection, were more efficiently killed by CVB than by CVB-reactive T cells. Our in vitro and ex vivo data highlight limited CD8+ T cell responses to CVB, supporting the rationale for CVB vaccination trials for type 1 diabetes prevention. CD8+ T cells recognizing structural and nonstructural CVB epitopes provide biomarkers to differentially follow response to infection and vaccination.


Asunto(s)
Infecciones por Coxsackievirus , Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Humanos , Linfocitos T CD8-positivos , Anticuerpos , Epítopos , Péptidos , Antivirales
3.
PLoS One ; 19(2): e0298455, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38354170

RESUMEN

Improving green innovation efficiency (GIE) is the key to achieve high-quality economic development in China, and the introduction of foreign direct investment (FDI) has become an important path choice to promote the GIE. Based on the data of 30 provinces in China, this paper explores the linear and nonlinear effects of FDI on GIE from both quantity and quality perspectives, and further analyzes the mediating role of environmental regulation level. The results show that: (1) From 2011 to 2020, the GIE of all provinces in China generally shows an upward trend. (2) The quantity and quality of FDI have a significant positive impact on the improvement of GIE in China's provinces, and this impact has regional heterogeneity. (3) The quantity and quality of FDI can promote the improvement of GIE in China through the level of environmental regulation (ER). (4) With the level of knowledge accumulation and GIE as the threshold variables, the quantity and quality of FDI have a single threshold effect on the GIE of China's provinces. The conclusions of this study provide some policy implications for local governments to make full use of FDI to perform green innovation activities.


Asunto(s)
Eficiencia , Inversiones en Salud , Humanos , Internacionalidad , China , Desarrollo Económico
4.
Nat Commun ; 15(1): 661, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38253617

RESUMEN

Understanding the nature and extent of non-canonical human leukocyte antigen (HLA) presentation in tumour cells is a priority for target antigen discovery for the development of next generation immunotherapies in cancer. We here employ a de novo mass spectrometric sequencing approach with a refined, MHC-centric analysis strategy to detect non-canonical MHC-associated peptides specific to cancer without any prior knowledge of the target sequence from genomic or RNA sequencing data. Our strategy integrates MHC binding rank, Average local confidence scores, and peptide Retention time prediction for improved de novo candidate Selection; culminating in the machine learning model MARS. We benchmark our model on a large synthetic peptide library dataset and reanalysis of a published dataset of high-quality non-canonical MHC-associated peptide identifications in human cancer. We achieve almost 2-fold improvement for high quality spectral assignments in comparison to de novo sequencing alone with an estimated accuracy of above 85.7% when integrated with a stepwise peptide sequence mapping strategy. Finally, we utilize MARS to detect and validate lncRNA-derived peptides in human cervical tumour resections, demonstrating its suitability to discover novel, immunogenic, non-canonical peptide sequences in primary tumour tissue.


Asunto(s)
Péptidos , Neoplasias del Cuello Uterino , Humanos , Femenino , Péptidos/genética , Neoplasias del Cuello Uterino/genética , Secuencia de Aminoácidos , Biblioteca de Péptidos , Benchmarking
5.
Micromachines (Basel) ; 14(12)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38138337

RESUMEN

Laser process technology provides a feasible method for directly manufacturing surface-metallized carbon fiber composites (CFCs); however, the laser's process parameters strongly influence on the adhesion strength between electroless copper and CFCs. Here, a nanosecond ultraviolet laser was used to fabricate electroless copper on the surface of CFCs. In order to achieve good adhesion strength, four key process parameters, namely, the laser power, scanning line interval, scanning speed, and pulse frequency, were optimized experimentally using response surface methodology, and a central composite design was utilized to design the experiments. An analysis of variance was conducted to evaluate the adequacy and significance of the developed regression model. Also, the effect of the process parameters on the adhesion strength was determined. The numerical analysis indicated that the optimized laser power, scanning line interval, scanning speed, and pulse frequency were 5.5 W, 48.2 µm, 834.0 mm/s, and 69.5 kHz, respectively. A validation test confirmed that the predicted results were consistent with the actual values; thus, the developed mathematical model can adequately predict responses within the limits of the laser process parameters being used.

6.
bioRxiv ; 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37662376

RESUMEN

Coxsackievirus B (CVB) infection of pancreatic ß cells is associated with ß-cell autoimmunity. We investigated how CVB impacts human ß cells and anti-CVB T-cell responses. ß cells were efficiently infected by CVB in vitro, downregulated HLA Class I and presented few, selected HLA-bound viral peptides. Circulating CD8+ T cells from CVB-seropositive individuals recognized only a fraction of these peptides, and only another sub-fraction was targeted by effector/memory T cells that expressed the exhaustion marker PD-1. T cells recognizing a CVB epitope cross-reacted with the ß-cell antigen GAD. Infected ß cells, which formed filopodia to propagate infection, were more efficiently killed by CVB than by CVB-reactive T cells. Thus, our in-vitro and ex-vivo data highlight limited T-cell responses to CVB, supporting the rationale for CVB vaccination trials for type 1 diabetes prevention. CD8+ T cells recognizing structural and non-structural CVB epitopes provide biomarkers to differentially follow response to infection and vaccination.

7.
Front Genet ; 14: 1227452, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37719706

RESUMEN

Innate lymphoid cells (ILCs) are a unique type of lymphocyte that differ from adaptive lymphocytes in that they lack antigen receptors, which primarily reside in tissues and are closely associated with fibers. Despite their plasticity and heterogeneity, identifying ILCs in peripheral blood can be difficult due to their small numbers. Accurately and rapidly identifying ILCs is critical for studying homeostasis and inflammation. To address this challenge, we collect single-cell RNA-seq data from 647 patients, including 26,087 transcripts. Background screening, Lasso analysis, and principal component analysis (PCA) are used to select features. Finally, we employ a deep neural network to classify lymphocytes. Our method achieved the highest accuracy compared to other approaches. Furthermore, we identified four genes that play a vital role in lymphocyte development. Adding these gene transcripts into model, we were able to increase the model's AUC. In summary, our study demonstrates the effectiveness of using single-cell transcriptomic analysis combined with machine learning techniques to accurately identify congenital lymphoid cells and advance our understanding of their development and function in the body.

8.
bioRxiv ; 2023 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-37745505

RESUMEN

Interferon (IFN)-α is the earliest cytokine signature observed in individuals at risk for type 1 diabetes (T1D), but its effect on the repertoire of HLA Class I (HLA-I)-bound peptides presented by pancreatic ß-cells is unknown. Using immunopeptidomics, we characterized the peptide/HLA-I presentation in in-vitro resting and IFN-α-exposed ß-cells. IFN-α increased HLA-I expression and peptide presentation, including neo-sequences derived from alternative mRNA splicing, post-translational modifications - notably glutathionylation - and protein cis-splicing. This antigenic landscape relied on processing by both the constitutive and immune proteasome. The resting ß-cell immunopeptidome was dominated by HLA-A-restricted ligands. However, IFN-α only marginally upregulated HLA-A and largely favored HLA-B, translating into a major increase in HLA-B-restricted peptides and into an increased activation of HLA-B-restricted vs. HLA-A-restricted CD8+ T-cells. A preferential HLA-B hyper-expression was also observed in the islets of T1D vs. non-diabetic donors, and we identified islet-infiltrating CD8+ T-cells from T1D donors reactive to HLA-B-restricted granule peptides. Thus, the inflammatory milieu of insulitis may skew the autoimmune response toward epitopes presented by HLA-B, hence recruiting a distinct T-cell repertoire that may be relevant to T1D pathogenesis.

9.
EBioMedicine ; 95: 104740, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37536063

RESUMEN

BACKGROUND: To resist the autoimmune attack characteristic of type 1 diabetes, insulin producing pancreatic ß cells need to evade T-cell recognition. Such escape mechanisms may be conferred by low HLA class I (HLA-I) expression and upregulation of immune inhibitory molecules such as Programmed cell Death Ligand 1 (PD-L1). METHODS: The expression of PD-L1, HLA-I and CXCL10 was evaluated in the human ß cell line, ECN90, and in primary human and mouse pancreatic islets. Most genes were determined by real-time RT-PCR, flow cytometry and Western blot. Activator and inhibitor of the AKT signaling were used to modulate PD-L1 induction. Key results were validated by monitoring activity of CD8+ Jurkat T cells presenting ß cell specific T-cell receptor and transduced with reporter genes in contact culture with the human ß cell line, ECN90. FINDINGS: In this study, we identify tryptophan (TRP) as an agonist of PD-L1 induction through the AKT signaling pathway. TRP also synergistically enhanced PD-L1 expression on ß cells exposed to interferon-γ. Conversely, interferon-γ-mediated induction of HLA-I and CXCL10 genes was down-regulated upon TRP treatment. Finally, TRP and its derivatives inhibited the activation of islet-reactive CD8+ T cells by ß cells. INTERPRETATION: Collectively, our findings indicate that TRP could induce immune tolerance to ß cells by promoting their immune evasion through HLA-I downregulation and PD-L1 upregulation. FUNDING: Dutch Diabetes Research Foundation, DON Foundation, the Laboratoire d'Excellence consortium Revive (ANR-10-LABX-0073), Agence Nationale de la Recherche (ANR-19-CE15-0014-01), Fondation pour la Recherche Médicale (EQ U201903007793-EQU20193007831), Innovative Medicines InitiativeINNODIA and INNODIA HARVEST, Aides aux Jeunes Diabetiques (AJD) and Juvenile Diabetes Research Foundation Ltd (JDRF).


Asunto(s)
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Animales , Ratones , Humanos , Triptófano , Interferón gamma/metabolismo , Células Secretoras de Insulina/metabolismo , Evasión Inmune , Antígeno B7-H1 , Proteínas Proto-Oncogénicas c-akt
10.
Front Microbiol ; 14: 1199024, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37577414

RESUMEN

Introduction: Rose black spot is an economically important disease that significantly decreases flower yield. Fungicide and biological control are effective approaches for controlling rose black spot. The objective of this study was to evaluate the effect of application of biological and chemical control agents, including Bacillus velezensis (GUAL210), Bacillus sp. (LKW) and fungicide (CP) on the black spot disease and rhizosphere fungal community structure of edible rose. Methods: In this study, the R. chinensis 'Crimson Glory' was taken as the research object, and the field experiment was designed by randomized block design. The experiment contained 3 treatments (CP, GUAL210, LKW) and 1 control. The control effect and growth promoting effect of fungicide and biological control on rose black spot were compared. The composition and diversity of rhizosphere soil fungal community of different treatments of rose were studied by high-throughput sequencing method. The fungal community composition, correlation of environmental factors and differences in metabolic pathways related to rose disease were analyzed, and the correlation between rhizosphere soil fungal community of rose and biological control of disease was explored. Results and discussion: Both disease incidence and disease index differed significantly among groups (LKW < GUAL210 < CP < CK), and disease control effect exhibited no significant difference between GUAL210 and LKW (60.96% and 63.86%, respectively). Biological control was superior to chemical control in terms of disease prevention effects and duration, and it significantly increased the number of branches and flowers of rose plants. Ascomycota and Basidiomycota accounted for more than 74% of the total fungal abundance, and the abundance of Ascomycota was highest in CK, followed by GUAL210, CP and LKW, which was consistent with the disease occurrence in each group. The analysis of metabolic pathways showed that the HSERMETANA-PWY in each experimental group was significantly lower than that in control group. The Shannon index in each experimental group was significantly lower than that in control group. PCoA analysis showed that the rhizosphere fungal community structure in each experimental group was significantly different from that in control group. Trichoderma, Paraphaeosphaeria, Suillus, Umbelopsis in GUAL210, and Galerina in LKW replaced Mortierella, Pestalotiopsis, Ustilaginoidea, Paraconiothyrium, Fusarium, and Alternaria as dominant flora, and played a nonneglectable role in reducing disease occurrence. The difference in rhizosphere fungal community structure had an important impact on the incidence of rose black spot disease. Biological control is crucial for establishing environment-friendly ecological agriculture. GUAL210 has promising prospects for application and development, and may be a good substitute for chemical control agents.

11.
Plant Dis ; 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37480253

RESUMEN

Tetrapanax papyrifer (Hook.) K. Koch, widely utilized in clinical practices in traditional Chinese medicine, is a medicinal plant whose dried stem pich exhibits activities such as lactation induction, diuresis, and anti-inflammatory effects. The species is native to the southwest of China, such as Guizhou and Yunnan provinces. It thrives in sunlight and warmth and is planted in fertile valleys in the region (Zhang et al. 2023). In July 2021, a leaf spot-like disease was observed on approximately 15% of T. papyrifer (Big T. papyrifer) in a field in Shibing County (127.2°E, 25.2°N), Guizhou Province, China. The symptomatic leaves displayed irregular, watery dark brown lesions with black conidiomata in gray centers and surrounded by yellow halos. To identify the causal agent leading to the disease, 15 symptomatic leaves from five trees in one field were collected. These leaves underwent surface sterilization, which included 30s in 75% ethanol, 2 min in 3% NaOCl, and three times of washing with sterilized distilled water. Thereafter, small pieces of the symptomatic leaf tissues (0.2 × 0.2 cm) were plated on PDA and incubated at 25°C for seven days (Fang 2007). Three isolates were obtained based on the improved single spore isolation method proposed by Gong et al. (2010), and named as GUTC 321, GUTC 523 and GUTC 873. The fungal colonies on PDA were villiform, creamy-white, whorled, and sparse aerial mycelium on the surface with black, gregarious conidiomata. The conidia were ellipsoid, mid brown to dark brown, mainly with 3-4 transverse septa, usually divided by longitudinal septum, often constricted at the septa, 21.8 (12.6-34.5) × 13.9 (8.8-19.8) µm (n=50). The morphological features were consistent with the descriptions of Pseudopithomyces chartarum (Ariyawansa et al. 2015). All three isolates exhibited identical morphological properties. The potential pathogen was confirmed as P. chartarum by amplification and sequencing of the internal transcribed spacer regions (ITS), large subunit ribosomal (LSU) and translation elongation factor 1 alpha (TEF1) genes with primers ITS4/ITS5, LROR/LR7 and EF-983F/EF-2218R, respectively (Ariyawansa et al. 2015; Jayasiriet al. 2019). BLASTn analyses of the sequences showed 100% identity among the three isolates and a high homology (ITS, 99.8%: 598/599; LSU, 100%: 853/853; and TEF1, 100%: 871/871) with those of P. chartarum sequences in GenBank (MT123059, OK655822, and MK360080, respectively). The sequences of the genes from isolate GUTC321 were deposited in GenBank under accession numbers OP269599 (ITS), OP237015 (LSU), and OR069689 (TEF1). Phylogenetic analyses of the concatenated ITS-LSU-TEF1 sequence (2,685 bp) of GUTC 321 using PhyloSuite 1.2.2 with PartitionFinder model revealed that the isolate clustered closely with P. chartarum isolate CBS 329.86T (Cecilia 1986). The pathogenicity of GUTC 321 was tested thereafter on ten healthy T. papyrifer plants grown in pots in growth chamber. The plants were inoculated by spraying with spore suspension (106 spores mL-1) of GUTC 321 or sterile water (control) onto leaves that had been slightly injured with sterilized SiO2 (0.1-0.25 mm) until runoff. The plants were maintained at 25°C in the growth chamber, and monitored for symptom development. Local lesions began to appear on all GUTC 321-inoculated leaves, but not on those of the control plants, 48 hours after inoculation. Seven days after the inoculation, lesions similar to those observed on field plants occurred on GUTC321-inoculated plants but not on the control plants, the lesions observed only in inoculated leaves. The same fungus was reisolated and identified based on the morphological characterization and molecular analyses (ITS, LSU and TEF1) from the infected leaves thus fulfilling Koch's postulates. To our knowledge, this is the first report of leaf spot on T. papyrifer caused by P. chartarum in China. Considering the significance of T. papyrifer in Chinese medicine, approximate management measures need to be developed and applied to control the disease in the crop.

12.
Oncogene ; 42(32): 2428-2438, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37400528

RESUMEN

The complement system is a major component of the innate immune system that works through the cytolytic effect of the membrane attack complex (MAC). Complement component 7 (C7) is essential for MAC assembly and its precisely regulated expression level is crucial for the cytolytic activity of MAC. We show that C7 is specifically expressed by the stromal cells in both mouse and human prostates. The expression level of C7 inversely correlates with clinical outcomes in prostate cancer. C7 is positively regulated by androgen signaling in the mouse prostate stromal cells. The androgen receptor directly transcriptionally regulates the mouse and human C7. Increasing C7 expression in the C57Bl/6 syngeneic RM-1 and Pten-Kras allografts suppresses tumor growth in vivo. Conversely, C7 haploinsufficiency promotes tumor growth in the transgenic adenocarcinoma of the mouse prostate (TRAMP) model. Interestingly, replenishing C7 in androgen-sensitive Pten-Kras tumors during androgen depletion only slightly enhances cellular apoptosis, highlighting the diverse mechanisms employed by tumors to counteract complement activity. Collectively, our research indicates that augmenting complement activity could be a promising therapeutic approach to impede the development of castration resistance in prostate cancer.


Asunto(s)
Andrógenos , Neoplasias de la Próstata , Masculino , Ratones , Humanos , Animales , Complemento C7/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Ratones Transgénicos , Neoplasias de la Próstata/patología , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo
13.
Prev Med ; 173: 107578, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37343728

RESUMEN

Today, the application of CT scanning technology is still limited. Therefore, an image observation method based on image recognition technology is proposed in this paper to study the impact of nutritional intervention on the rehabilitation level and quality of life of diabetic foot patients. Firstly, in view of the noise problems existing in CT images, this paper adopts the denoising technology, in which Gaussian noise and salt and pepper noise denoising algorithms are mainly used. Noise interference in the image can be removed by denoising processing, and the clarity and quality of the image can be improved. Subsequently, in order to improve the recognition and classification accuracy of the image, data enhancement and data standardization techniques are adopted to normalize the pixel values of the image, so as to make different images comparable, so as to improve the stability and classification accuracy of the model. Finally, CNN model is used to study image classification. The effects of nutritional intervention on the rehabilitation level and quality of life of patients with diabetic foot were investigated by setting up a comparative experiment. The results showed that nutrition intervention nursing can effectively improve the rehabilitation level of diabetic foot patients, improve the quality of life, improve nursing satisfaction.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Humanos , Calidad de Vida , Relación Señal-Ruido , Algoritmos , Tecnología
14.
Nat Commun ; 14(1): 3764, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37353502

RESUMEN

It is challenging to grow atomically thin non-van der Waals perovskite due to the strong electronic coupling between adjacent layers. Here, we present a colloid-driven low supersaturation crystallization strategy to grow atomically thin Cs3Bi2Br9. The colloid solution drives low-concentration solute in a supersaturation state, contributing to initial heterogeneous nucleation. Simultaneously, the colloids provide a stable precursor source in the low-concentration solute. The surfactant is absorbed in specific crystal nucleation facet resulting in the anisotropic growth of planar dominance. Ionic perovskite Cs3Bi2Br9 is readily grown from monolayered to six-layered Cs3Bi2Br9 corresponding to thicknesses of 0.7, 1.6, 2.7, 3.6, 4.6 and 5.7 nm. The atomically thin Cs3Bi2Br9 presents layer-dependent nonlinear optical performance and stacking-induced second harmonic generation. This work provides a concept for growing atomically thin halide perovskite with non-van der Waal structures and demonstrates potential application for atomically thin single crystals' growth with strong electronic coupling between adjacent layers.


Asunto(s)
Bismuto , Compuestos Inorgánicos , Cristalización , Compuestos de Calcio , Coloides
15.
Comput Biol Med ; 161: 107038, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37230017

RESUMEN

Polyp segmentation plays a role in image analysis during colonoscopy screening, thus improving the diagnostic efficiency of early colorectal cancer. However, due to the variable shape and size characteristics of polyps, small difference between lesion area and background, and interference of image acquisition conditions, existing segmentation methods have the phenomenon of missing polyp and rough boundary division. To overcome the above challenges, we propose a multi-level fusion network called HIGF-Net, which uses hierarchical guidance strategy to aggregate rich information to produce reliable segmentation results. Specifically, our HIGF-Net excavates deep global semantic information and shallow local spatial features of images together with Transformer encoder and CNN encoder. Then, Double-stream structure is used to transmit polyp shape properties between feature layers at different depths. The module calibrates the position and shape of polyps in different sizes to improve the model's efficient use of the rich polyp features. In addition, Separate Refinement module refines the polyp profile in the uncertain region to highlight the difference between the polyp and the background. Finally, in order to adapt to diverse collection environments, Hierarchical Pyramid Fusion module merges the features of multiple layers with different representational capabilities. We evaluate the learning and generalization abilities of HIGF-Net on five datasets using six evaluation metrics, including Kvasir-SEG, CVC-ClinicDB, ETIS, CVC-300, and CVC-ColonDB. Experimental results show that the proposed model is effective in polyp feature mining and lesion identification, and its segmentation performance is better than ten excellent models.


Asunto(s)
Colonoscopía , Aprendizaje , Benchmarking , Procesamiento de Imagen Asistido por Computador , Semántica
16.
J Hazard Mater ; 456: 131657, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37245362

RESUMEN

Oxidative degradation can effectively degrade aromatic emerging contaminants (ECs). However, the degradability of lone inorganic/biogenic oxides or oxidases is typically limited when treating polycyclic ECs. Herein, we report a dual-dynamic oxidative system comprising engineered Pseudomonas and biogenic Mn oxides (BMO), which completely degrades diclofenac (DCF), a representative halogen-containing polycyclic EC. Correspondingly, recombinant Pseudomonas sp. MB04R-2 was constructed via gene deletion and chromosomal insertion of a heterologous multicopper oxidase cotA, allowing for enhanced Mn(II)-oxidizing activity and rapid formation of the BMO aggregate complex. Additionally, we characterized it as a micro/nanostructured ramsdellite (MnO2) composite using multiple-phase composition and fine structure analyses. Furthermore, using real-time quantitative polymerase chain reaction, gene knockout, and expression complementation of oxygenase genes, we demonstrated the central and associative roles of intracellular oxygenases and cytogenic/BMO-derived free radicals (FRs) in degrading DCF and determined the effects of FR excitation and quenching on the DCF degradation efficiency. Finally, after identifying the degraded intermediates of 2H-labeled DCF, we constructed the DCF metabolic pathway. In addition, we evaluated the degradation and detoxification effects of the BMO composite on DCF-containing urban lake water and on biotoxicity in zebrafish embryos. Based on our findings, we proposed a mechanism for oxidative degradation of DCF by associative oxygenases and FRs.


Asunto(s)
Óxidos , Contaminantes Químicos del Agua , Animales , Óxidos/química , Diclofenaco/toxicidad , Diclofenaco/química , Compuestos de Manganeso/química , Pseudomonas/genética , Pseudomonas/metabolismo , Oxigenasas/metabolismo , Pez Cebra/metabolismo , Oxidación-Reducción , Estrés Oxidativo , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/química
17.
Insects ; 14(4)2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37103166

RESUMEN

The bamboo bug Notobitus meleagris (Fabricius, 1787) is a serious pest of bamboo shoots in China, India, Myanmar, Vietnam, and Singapore. The antennae of the nymphal instars and adults of N.meleagris are involved in communication among individuals and finding the host plants. In order to understand the morphology of antennal sensilla, their types, and the distribution of sensilla on the antennae of nymphal instars and adults in N. meleagris, we studied the morphology of antennal sensilla with a scanning electron microscope. The antennae of the nymphs and adults comprised the scape, pedicel, and two flagellomeres. Four types and eight subtypes of sensilla were identified in the nymphal instars (sensilla trichodea [St].1, St.2, St.3, sensilla basiconica [Sb].1, Sb.2, sensilla chaetica [Sc].1, Sc.2, sensilla coeloconica [Sco].1), whereas those of the adults had five types and eleven subtypes of sensilla (St.1, St.2, St.3, Sb.1, Sb.2, Sb.3, Sc.1, Sc.2, Sco.1, Sco.2, and sensilla campaniformia [Sca]). There are significant differences in the number, type, and size of the sensilla in different nymphal instars, which increases with the increase in nymphal instars. There was no sexual dimorphism observed in the adult sensilla; however, the length and diameter of St.3, Sb.2, and Sb.3 were sexually dimorphic. The potential functions of each sensillum were discussed based on the morphology and distribution of the antennal sensilla and were compared with similar published studies. Our results provide primary data for further research on the behavioral mechanism, green prevention, and control of N. meleagris.

18.
J Hazard Mater ; 453: 131363, 2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37043850

RESUMEN

In the present work, a novel, floral-like, magnetic sodalite microsphere (SODM) was synthesized in situ by using fly ash (FA) and metakaolin (MK) as raw materials and was used to remove Cd(II) from water. Its magnetism can solve the problems of adsorbent recovery and possible secondary pollution. During the static adsorption, SODM shows a maximum adsorption capacity of 245.17 mg/g. The adsorption of Cd(II) on the SODM surface is spontaneous, exothermic, and physicochemical adsorption, which was evaluated by thermodynamics, kinetics, and isotherm studies. During dynamic adsorption, SODM shows a maximum adsorption capacity of 342.74 mg/g in the simulated solution prepared by the deionized water, compared to 215.88 mg/g in the simulated solution prepared using Xiangsi Lake water from Guangxi Minzu University. At 0.5 g SODM dosage in the dynamic adsorption, the adsorption capacity could rise to 632.81 mg/g. These results demonstrated the excellent Cd (II) adsorption performance of the SODM. The adsorption of cadmium on the SODM surface includes the synergistic effects of electrostatic attraction, ion exchange, and surface coordination reaction. Besides, the SODM shows good regeneration performance in both the deionized water and Xiangsi Lake water. The present study explores SODM as an adsorbent for the Cd (II) removal from wastewater and unbolts the industrial applicability of the SODM in the field of wastewater purification.

19.
Elife ; 122023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-36995951

RESUMEN

T-cell receptors (TCRs) are formed by stochastic gene rearrangements, theoretically generating >1019 sequences. They are selected during thymopoiesis, which releases a repertoire of about 108 unique TCRs per individual. How evolution shaped a process that produces TCRs that can effectively handle a countless and evolving set of infectious agents is a central question of immunology. The paradigm is that a diverse enough repertoire of TCRs should always provide a proper, though rare, specificity for any given need. Expansion of such rare T cells would provide enough fighters for an effective immune response and enough antigen-experienced cells for memory. We show here that human thymopoiesis releases a large population of clustered CD8+ T cells harboring α/ß paired TCRs that (i) have high generation probabilities and (ii) a preferential usage of some V and J genes, (iii) which CDR3 are shared between individuals, and (iv) can each bind and be activated by multiple unrelated viral peptides, notably from EBV, CMV, and influenza. These polyspecific T cells may represent a first line of defense that is mobilized in response to infections before a more specific response subsequently ensures viral elimination. Our results support an evolutionary selection of polyspecific α/ß TCRs for broad antiviral responses and heterologous immunity.


Asunto(s)
Antígenos Virales , Linfocitos T CD8-positivos , Humanos , Antígenos Virales/genética , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T/genética , Péptidos
20.
Plant Dis ; 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36856648

RESUMEN

Tobacco (Nicotiana tabacum L.) is an important economic crop belonging to family Solanaceae and is widely cultivated in China (Basit 2021). From April to July in 2022, a foliar disease with symptoms similar to grey spot was extensively observed on tobacco in Guangxi Province (24°52' N, 111°23' E), China. Field surveys were conducted in 18 towns and the disease incidence was 0.89% to 6.95%. Symptomatic leaves displayed irregular, dark brown lesions surrounded by yellow halos and accompanied with black conidiomata in gray centers (Fig 1A-E). Symptomatic leaves were collected from 54 different tobacco plants. After surface sterilization (0.5 min in 75% ethanol and 1 min in 3% NaOCl, washed three times with sterilized distilled water), small pieces of symptomatic leaf tissue (0.2 × 0.2 cm) were plated on PDA and incubated at 25°C for 5 days (Fang 2007). Three single-spore isolates, GUCC BZ6-3, GUCC LJ3-4, and GUCC XH1-13 were obtained, which were identical in morphology and molecular analysis. Therefore, the representative isolate GUCC BZ6-3 was used for further study. The colonies on PDA were villiform, greyish (Fig 1F-G). Conidia were abundant, ovoid, with 2-6 transverse septa and 1-2 longitudinal septa 12.60 (9.43 to 14.76) × 4.30 (3.57 to 5.14) µm (n=50) (Fig 1H-S). The morphological features were consistent with Alternaria alstroemeriae E.G. Simmons & C.F. Hill (Simmons 2007; Nishikawa & Nakashima, 2013). The pathogen was confirmed to be A. alstroemeriae by amplification and sequencing of the ITS, GAPDH, LSU, TEF1, and RBP2 genes using primers ITS1/ITS4, gpd1/gpd2, LSU1Fd/LR5, EF1-728F/EF1-986R, and RPB2-5F2/fRPB2-7cR, respectively (Woudenberg 2013). The sequences of the PCR products were deposited in GenBank with accession numbers ON693856 (RBP2), ON714497 (ITS), ON694345 (GAPDH), ON931420 (TEF1) and ON714499 (LSU). BLAST searches of the obtained sequences revealed 99% (565/567 nucleotides), 99% (577/579 nucleotides), 99% (908/911 nucleotides), 99% (238/239 nucleotides), and 99% (751/753 nucleotides) homology with those of A. alstroemeriae in GenBank (MH863036, KP124154, MH874589, KP125072, and KP124765, respectively). Phylogenetic analyses of the sequence data consisted of Bayesian and Maximum likelihood analyses of the combined aligned dataset (MEGA 7.0 and PhyloSuite 1.2.2). The GUCC BZ6-3 in a well-supported cluster with A. alstroemeriae (Fig 2). The pathogen was thus identified as A. alstroemeriae based on morphological characterization and molecular analyses. The pathogenicity of GUCC BZ6-3 was tested through pot assay and carried out three times (Fang 2007). Ten healthy 30-day-old tobacco plants were inoculated by spraying a spore suspension (106 spores·ml-1) of strain GUCC BZ6-3 onto leaves until runoff, and the control leaves were sprayed with sterile water. The plants were maintained at 28°C with high relative humidity (95%) in a growth chamber. The symptoms developed on all inoculated leaves but not on the control. The lesions were first visible 48 h after inoculation, and typical lesions similar to those observed on field plants appeared after 7 days. The same fungus was reisolated and identified based on the morphological characterization and molecular analyses from the infected leaves but not from the noninoculated leaves. Results of pathogenicity experiments fulfilled Koch's postulates. To our knowledge, this is the first report of grey spot disease on tobacco caused by A. alstroemeriae in China. Our findings would be of great importance for the diagnosis and control of the emerging grey spot on tobacco.

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