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A novel cyclic chalcone fluorescent probe C-PN was synthesized to detect ONOO-. After reaction with peroxynitrite, the double bond of C-PN in the cyclic chalcone structure was disconnected, which caused the change of intramolecular charge transfer (ICT) effect, emitting blue fluorescence and quenching orange red fluorescence. Visible to the naked eye, the color of the probe solution changed. The probe showed low sensitivity (detection limit = 20.2 nm), short response time (less than 60 s) at low concentration of ONOO-, good visibility, and good selectivity and stability for ONOO-.
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BACKGROUND: In previous studies, the 308-nm light-emitting diode (LED) has been proven safe and effective for treating vitiligo. However, direct comparisons between the 308-nm LED and 308-nm excimer lamp (308-nm MEL) for the treatment of vitiligo are lacking. OBJECTIVE: To compare the efficacy of the 308-nm LED and 308-nm MEL for treating nonsegmental stable vitiligo. PATIENTS AND METHODS: This randomized controlled trial was conducted between January 2018 and August 2023. Enrolled patients were randomly assigned to either the 308-nm LED or the 308-nm MEL groups, both receiving 16 treatment sessions. Adverse events that occurred during the treatment were documented. RESULTS: In total, 269 stable vitiligo patches from 174 patients completed the study. A total of 131 lesions were included in the 308-nm LED group, and 138 lesions were included in the 308-nm MEL group. After 16 treatment sessions, 38.17% of the vitiligo patches in the 308-nm LED group achieved repigmentation of at least 50% versus 38.41% in the 308-nm MEL group. The two devices exhibited similar results in terms of efficacy for a repigmentation of at least 50% (p = .968). The incidence of adverse effects with the two phototherapy devices was comparable (p = .522). CONCLUSIONS: Treatment of vitiligo with the 308-nm LED had a similar efficacy rate to the 308-nm MEL, and the incidence of adverse effects was comparable between the two devices.
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Vitiligo , Humanos , Vitiligo/radioterapia , Vitiligo/terapia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Adolescente , Lasers de Excimer/uso terapêutico , Lasers de Excimer/efeitos adversos , Adulto Jovem , CriançaRESUMO
BACKGROUND: Psoriasis is a chronic inflammatory dermatosis with an unclear pathogenesis. Mast cells (MCs) can serve as a bridge between innate and adaptive immunity and are involved in the regulation of the inflammatory state and immune homeostasis in diseases. MCs constitutively express interleukin-33 receptor T1/ST2 (IL-33R). IL-33 is a potent MCs activator that is actively secreted by keratinocytes in psoriasis. However, the regulatory role of MCs in psoriasis remains uncertain. Therefore, we hypothesised that IL-33 could promote MC activation to regulate psoriasis development. METHODS: We performed experiments on wild-type (WT) and MC-deficient (Kit Wsh/Wsh) mice, established psoriasis-like mouse models using imiquimod (IMQ), and performed RNA sequencing and transcriptomic analysis of skin lesions. Exogenous administration was performed using recombinant IL-33. Validation and evaluation were performed using PSI scoring, immunofluorescence, immunohistochemistry, and qPCR. RESULTS: We observed an upregulation in the number and activation of MCs in patients with psoriasis and in IMQ-induced psoriasis-like dermatitis. Deficiency of MCs ameliorates IMQ-induced psoriatic dermatitis at an early stage. IL-33 is increased and co-localized with MCs in the dermis of psoriasis-like lesions using immunofluorescence. Compared to WT mice, IMQ-induced KitWsh/Wsh mice demonstrated a delayed response to exogenous IL-33. CONCLUSIONS: MCs are activated by IL-33 in the early stages of psoriasis and exacerbate psoriasis-associated skin inflammation. The regulation of MC homeostasis may be a potential therapeutic strategy for psoriasis. Video Abstract.
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Dermatite , Psoríase , Animais , Camundongos , Dermatite/patologia , Imiquimode , Interleucina-33/uso terapêutico , Mastócitos , Camundongos Endogâmicos BALB C , Psoríase/induzido quimicamente , Psoríase/tratamento farmacológico , Pele/patologiaRESUMO
Breast remodelling is a major therapeutic choice in radical mastectomy. Breast reconstruction is regarded as a promising option for the treatment of breast cancer. The purpose of this meta-analysis was to investigate the effect of Post mastectomy radiotherapy (PMRT) on postoperative wound complications in breast carcinoma. A comprehensive review of documents was conducted between the date of establishment and the 28th of August 2023. In all of the trials, patients were treated with breast cancer. The researchers chose 11 publications out of 8068 related studies. Two researchers examined these publications to satisfy the inclusion criteria. Among the 516 patients who had received radiation therapy in the course of the operation, 1772 had not received radiation therapy. The impact of radiation therapy and non-radiation therapy in breast cancer patients after breast reconstruction was reported in 8 studies, and the incidence of postoperative wound infection in non-radiation group was significantly lower (OR, 1.95; 95% CI, 1.26-3.02 p = 0.003). In nine studies, There is not considered to have achieved statistical significance between radiation therapy and non-radiation treatment for post-operation wound dehiscence in breast cancer patients who had received chemotherapy (OR, 1.61; 95% CI, 0.70-3.72 p = 0.27). The results of six trials demonstrated that radiation therapy and non-radiation therapy had no statistical significance on post-operation haemorrhage in breast cancer patients (OR, 1.02; 95% CI, 0.42-2.47 p = 0.96). The results of 7 trials demonstrated that radiation therapy and non-radiation therapy had no significant impact on the post-operation of skin necrosis (OR, 1.22; 95% CI, 0.66-2.28 p = 0.53). Two trials demonstrated that those without radiation therapy were less likely than those who received radiation therapy in skin contracture in patients (OR, 7.24; 95% CI, 1.80-29.10 p = 0.005). Regarding the incidence of wound infection and cutaneous contraction was higher in the radiation group.
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In coordination-based supramolecular materials such as metallogels, simultaneous temporal and spatial control of their assembly remains challenging. Here, we demonstrate that the combination of light with acids as stimuli allows for the spatiotemporal control over the architectures, mechanical properties, and shape of porous soft materials based on metal-organic polyhedra (MOPs). First, we show that the formation of a colloidal gel network from a preformed kinetically trapped MOP solution can be triggered upon addition of trifluoroacetic acid (TFA) and that acid concentration determines the reaction kinetics. As determined by time-resolved dynamic light scattering, UV-vis absorption, and 1H NMR spectroscopies and rheology measurements, the consequences of the increase in acid concentration are (i) an increase in the cross-linking between MOPs; (ii) a growth in the size of the colloidal particles forming the gel network; (iii) an increase in the density of the colloidal network; and (iv) a decrease in the ductility and stiffness of the resulting gel. We then demonstrate that irradiation of a dispersed photoacid generator, pyranine, allows the spatiotemporal control of the gel formation by locally triggering the self-assembly process. Using this methodology, we show that the gel can be patterned into a desired shape. Such precise positioning of the assembled structures, combined with the stable and permanent porosity of MOPs, could allow their integration into devices for applications such as sensing, separation, catalysis, or drug release.
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Coloides/química , Géis/química , Estruturas Metalorgânicas/química , Sulfonatos de Arila/química , Sulfonatos de Arila/efeitos da radiação , Coloides/síntese química , Módulo de Elasticidade , Géis/síntese química , Luz , Estruturas Metalorgânicas/síntese química , Polimerização/efeitos da radiação , Porosidade , Ácido Trifluoracético/químicaRESUMO
While monolithic giant earth observation satellites still have obvious advantages in regularity and accuracy, distributed satellite systems are providing increased flexibility, enhanced robustness, and improved responsiveness to structural and environmental changes. Due to increased system size and more complex applications, traditional centralized methods have difficulty in integrated management and rapid response needs of distributed systems. Aiming to efficient missions scheduling in distributed earth observation satellite systems, this paper addresses the problem through a networked game model based on a game-negotiation mechanism. In this model, each satellite is viewed as a "rational" player who continuously updates its own "action" through cooperation with neighbors until a Nash Equilibria is reached. To handle static and dynamic scheduling problems while cooperating with a distributed mission scheduling algorithm, we present an adaptive particle swarm optimization algorithm and adaptive tabu-search algorithm, respectively. Experimental results show that the proposed method can flexibly handle situations of different scales in static scheduling, and the performance of the algorithm will not decrease significantly as the problem scale increases; dynamic scheduling can be well accomplished with high observation payoff while maintaining the stability of the initial plan, which demonstrates the advantages of the proposed methods.
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Psoriasis is a chronic disease and often requires long-term treatment, especially in patients with moderate-to-severe psoriasis. It remains controversial whether the doses of systemic medications could be tapered or if these medications could be discontinued among patients in clinical remission. In this review, we summarize whether it is possible to taper or discontinue methotrexate, cyclosporine, and biologics while controlling the relapse rates of psoriasis. Based on the current evidence, methotrexate and biologics should not be discontinued for psoriasis patients with low disease activity. However, the doses of these medications could be tapered by reducing the maintenance dose or increasing the between-dose intervals. If the disease recurs, methotrexate and biologics should be restarted at their standard doses, and for cyclosporine, the dose can be maintained or discontinued progressively. If patients relapse, cyclosporine can be given again. The decisions to taper or discontinue anti-psoriasis drugs need to account for both benefits and risks and should be individualized according to patients' disease severity, quality of life, and presence of comorbidities.
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Fármacos Dermatológicos , Psoríase , Ciclosporina/efeitos adversos , Fármacos Dermatológicos/efeitos adversos , Humanos , Metotrexato/efeitos adversos , Psoríase/diagnóstico , Psoríase/tratamento farmacológico , Qualidade de Vida , Índice de Gravidade de DoençaRESUMO
We address the problem of lung CT image registration, which underpins various diagnoses and treatments for lung diseases. The main crux of the problem is the large deformation that the lungs undergo during respiration. This physiological process imposes several challenges from a learning point of view. In this paper, we propose a novel training scheme, called stochastic decomposition, which enables deep networks to effectively learn such a difficult deformation field during lung CT image registration. The key idea is to stochastically decompose the deformation field, and supervise the registration by synthetic data that have the corresponding appearance discrepancy. The stochastic decomposition allows for revealing all possible decompositions of the deformation field. At the learning level, these decompositions can be seen as a prior to reduce the ill-posedness of the registration yielding to boost the performance. We demonstrate the effectiveness of our framework on Lung CT data. We show, through extensive numerical and visual results, that our technique outperforms existing methods.
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Processos Estocásticos , Tomografia Computadorizada por Raios X , Tomografia Computadorizada por Raios X/métodos , Humanos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Pulmão/diagnóstico por imagem , Algoritmos , Pneumopatias/diagnóstico por imagem , Pneumopatias/fisiopatologiaRESUMO
Exposure to ultraviolet radiation can lead to skin photoaging, which increases the risk of skin tumors. This study aims to investigate how microRNA m6A modification contributes to skin photoaging. This study found that skin fibroblasts exposed to a single UVB dose of 30 mJ/cm2 exhibited characteristics of photoaging. The m6A level of total RNA decreased in photoaged cells with a down-regulated level of METTL14, and overexpression of METTL14 displayed a photoprotective function. Moreover, miR-100-3p was a downstream target of METTL14. And METTL14 could affect pri-miR-100 processing to mature miR-100-3p in an m6A-dependent manner via DGCR8. Furthermore, miR-100-3p targeted at 3' end untranslated region of ERRFI1 mRNA with an inhibitory effect on translation. Additionally, photoprotective effects of overexpression of METTL14 were reversed by miR-100-3p inhibitor or overexpression of ERRFI1. In UVB-induced photoaging of human skin fibroblasts, METTL14-dependent m6A can regulate miR-100-3p maturation via DGCR8 and affect skin fibroblasts photoaging through miR-100-3p/ERRFI1 axis.
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Fibroblastos , Metiltransferases , MicroRNAs , Envelhecimento da Pele , Raios Ultravioleta , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Metiltransferases/metabolismo , Metiltransferases/genética , Envelhecimento da Pele/efeitos da radiação , Envelhecimento da Pele/genética , Pele/metabolismo , Pele/efeitos da radiação , Adenosina/análogos & derivados , Adenosina/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genéticaRESUMO
BACKGROUND: Cholangiocarcinoma (CCA), a malignancy that arises from biliary epithelial cells, has a dismal prognosis, and few targeted therapies are available. Aurora B, a key mitotic regulator, has been reported to be involved in the progression of various tumors, yet its role in CCA is still unclarified. METHODS: Human CCA tissues and murine spontaneous CCA models were used to assess Aurora B expression in CCA. A loss-of-function model was constructed in CCA cells to determine the role of Aurora B in CCA progression. Subcutaneous and liver orthotopic xenograft models were used to assess the therapeutic potential of Aurora B inhibitors in CCA. RESULTS: In murine spontaneous CCA models, Aurora B was significantly upregulated. Elevated Aurora B expression was also observed in 62.3% of human specimens in our validation cohort (143 CCA specimens), and high Aurora B expression was positively correlated with pathological parameters of tumors and poor survival. Knockdown of Aurora B by siRNA and heteroduplex oligonucleotide (HDO) or an Aurora B kinase inhibitor (AZD1152) significantly suppressed CCA progression via G2/M arrest induction. An interaction between Aurora B and c-Myc was found in CCA cells. Targeting Aurora B significantly reduced this interaction and accelerated the proteasomal degradation of c-Myc, suggesting that Aurora B promoted the malignant properties of CCA by stabilizing c-Myc. Furthermore, sequential application of AZD1152 or Aurora B HDO drastically improved the efficacy of gemcitabine in CCA. CONCLUSIONS: Aurora B plays an essential role in CCA progression by modulating c-Myc stability and represents a new target for treatment and chemosensitization in CCA.
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Nuclear detection, segmentation and morphometric profiling are essential in helping us further understand the relationship between histology and patient outcome. To drive innovation in this area, we setup a community-wide challenge using the largest available dataset of its kind to assess nuclear segmentation and cellular composition. Our challenge, named CoNIC, stimulated the development of reproducible algorithms for cellular recognition with real-time result inspection on public leaderboards. We conducted an extensive post-challenge analysis based on the top-performing models using 1,658 whole-slide images of colon tissue. With around 700 million detected nuclei per model, associated features were used for dysplasia grading and survival analysis, where we demonstrated that the challenge's improvement over the previous state-of-the-art led to significant boosts in downstream performance. Our findings also suggest that eosinophils and neutrophils play an important role in the tumour microevironment. We release challenge models and WSI-level results to foster the development of further methods for biomarker discovery.
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Algoritmos , Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Núcleo Celular/patologia , Técnicas Histológicas/métodosRESUMO
Genetically encoded fluorescent indicators are powerful tools for tracking cellular dynamic processes. Engineering these indicators requires balancing screening dimensions with screening throughput. Herein, we present a functional imaging-guided photoactivatable cell selection platform, Faculae (functional imaging-activated molecular evolution), for linking microscopic phenotype with the underlying genotype in a pooled mutant library. Faculae is capable of assessing tens of thousands of variants in mammalian cells simultaneously while achieving photoactivation with single-cell resolution in seconds. To demonstrate the feasibility of this approach, we applied Faculae to perform multidimensional directed evolution for far-red genetically encoded calcium indicators (FR-GECIs) with improved brightness (Nier1b) and signal-to-baseline ratio (Nier1s). We anticipate that this image-based pooled screening method will facilitate the development of a wide variety of biomolecular tools.
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Corantes , Engenharia , Animais , Evolução Molecular , Biblioteca Gênica , Genótipo , MamíferosRESUMO
Medical image segmentation is an important task in medical imaging, as it serves as the first step for clinical diagnosis and treatment planning. While major success has been reported using deep learning supervised techniques, they assume a large and well-representative labeled set. This is a strong assumption in the medical domain where annotations are expensive, time-consuming, and inherent to human bias. To address this problem, unsupervised segmentation techniques have been proposed in the literature. Yet, none of the existing unsupervised segmentation techniques reach accuracies that come even near to the state-of-the-art of supervised segmentation methods. In this work, we present a novel optimization model framed in a new convolutional neural network (CNN)-based contrastive registration architecture for unsupervised medical image segmentation called CLMorph. The core idea of our approach is to exploit image-level registration and feature-level contrastive learning, to perform registration-based segmentation. First, we propose an architecture to capture the image-to-image transformation mapping via registration for unsupervised medical image segmentation. Second, we embed a contrastive learning mechanism in the registration architecture to enhance the discriminative capacity of the network at the feature level. We show that our proposed CLMorph technique mitigates the major drawbacks of existing unsupervised techniques. We demonstrate, through numerical and visual experiments, that our technique substantially outperforms the current state-of-the-art unsupervised segmentation methods on two major medical image datasets.
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Pemigatinib, a pan-FGFR inhibitor, is approved to treat intrahepatic cholangiocarcinoma (ICC) harboring FGFR2 fusion mutations. Improving its targeting of FGFR2 fusions remains an unmet clinical need due to its pan selectivity and resistance. Here, we report a cholesterol-conjugated DNA/RNA heteroduplex oligonucleotide targeting the chimeric site in FGFR2-AHCYL1 (F-A Cho-HDO) that accumulates in ICC through endocytosis of low-density lipoprotein receptor (LDLR), which is highly expressed in both human and murine ICC. F-A Cho-HDO was determined to be a highly specific, sustainable, and well-tolerated agent for inhibiting ICC progression through posttranscriptional suppression of F-A in ICC patient-derived xenograft mouse models. Moreover, we identified an EGFR-orchestrated bypass signaling axis that partially offset the efficacy of F-A Cho-HDO. Mechanistically, EGFR-induced STAT1 upregulation promoted asparagine (Asn) synthesis through direct transcriptional upregulation of asparagine synthetase (ASNS) and dictated cell survival by preventing p53-dependent cell cycle arrest. Asn restriction with ASNase or ASNS inhibitors reduced the intracellular Asn, thereby reactivating p53 and sensitizing ICC to F-A Cho-HDO. Our findings highlight the application of genetic engineering therapies in ICC harboring FGFR2 fusions and reveal an axis of adaptation to FGFR2 inhibition that presents a rationale for the clinical evaluation of a strategy combining FGFR2 inhibitors with Asn depletion.
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BACKGROUND: Xylo-oligomers are a kind of high value-added products in biomass fractionation. Although there are several chemical methods to obtain xylo-oligomers from biomass, the reports about the deep eutectic solvents (DESs)-mediated co-production of xylo-oligomers and fermentable sugars and the related kinetic mechanism are limited. RESULTS: In this work, glycolic acid-based DESs were used to obtain xylo-oligomers from corncob. The highest xylo-oligomers yield of 65.9% was achieved at 120 °C for 20 min, of which the functional xylo-oligosaccharides (XOSs, DP 2-5) accounted for up to 31.8%. Meanwhile, the enzymatic digestion of cellulose and xylan in residues reached 81.0% and 95.5%, respectively. Moreover, the addition of metal inorganic salts significantly accelerated the hydrolysis of xylan and even the degradation of xylo-oligomers in DES, thus resulting in higher selectivity of xylan removal. AlCl3 showed the strongest synergistic effect with DES on accelerating the processes, while FeCl2 is best one for xylo-oligomers accumulation, affording the highest xylo-oligomers yield of 66.1% for only 10 min. Furthermore, the kinetic study indicates that the 'potential hydrolysis degree' model could well describe the xylan hydrolysis processes and glycolic acid/lactic acid (3:1) is a promising solvent for xylo-oligomers production, in particular, it worked well with FeCl2 for the excellent accumulation of xylo-oligomers. CONCLUSIONS: Glycolic acid-based deep eutectic solvents can be successfully applied in corncob fractionation with excellent xylo-oligomers and fermentable sugars yields on mild conditions, and the large amount of xylo-oligosaccharides accumulation could be achieved by specific process controlling. The strategies established here can be useful for developing high-valued products from biomass.
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Ferroptosis is a recognized novel form of programmed cell death pathway, featuring abnormalities in iron metabolism, SystemXc-/glutathione axis, and lipid peroxidation regulation. A variety of ferroptosis inducers can influence glutathione peroxidase directly or indirectly via diverse pathways, leading to decreased antioxidant capacity, accumulated cellular lipid peroxides, and finally inducing ferroptosis. To date, mounting studies confirm the association of ferroptosis with various cutaneous diseases, including skin homeostasis, neoplastic diseases, infectious diseases, genetic skin disease, inflammatory skin diseases, and autoimmune diseases. There are shared characteristics regarding ferroptosis and various cutaneous diseases in terms of pathophysiological mechanisms, such as oxidative stress associated with iron metabolism disorder and accumulated lipid peroxides. Therefore, we summarize the current knowledge regarding the mechanisms involved in the regulation of ferroptosis for further discussion of its role in the pathogenesis and prognosis of skin diseases. Gaining insight into the underlying mechanisms of ferroptosis and the associated dermatological disorders could illuminate the pathogenesis and treatments of different cutaneous diseases.
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Objective: This study aimed to explore whether astragalus polysaccharides (APS) could treat herpes simplex by increasing tissue-resident memory CD8+ T cells (CD8+ TRM cells) and analyze its potential mechanism using the network pharmacologic approach. Methods: C57BL/6J male mice aged 6-8 weeks were divided into a model group with HSV-1 infection treated by saline, a control group without HSV-1 infection but treated by saline, and an APS group with HSV-1 infection treated by APS. Clinical signs were observed, and the disease score was recorded every day. The skin lesions on day 9 after infection were taken for flow cytometric analysis to evaluate CD8+ TRM cells. Network pharmacologic analysis was performed to select the potential protein targets of astragalus associated with herpes simplex. Besides, Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed. The peripheral blood from the retroorbital venous plexus was collected to evaluate the levels of serum interferon-γ (IFN-γ) and interleukin 12 (IL-12). The comparisons of clinical signs, the disease score, CD8+ TRM cells, the serum IFN-γ, and IL-12 levels were performed among the three groups. Results: Compared with the model group, the disease score in the APS group was significantly lower (p < 0.05). On the day 9 after HSV-1 infection, there was no significant difference in the body weight of mice among the three groups. However, compared with the control group or model group, the spleen weight in the APS group increased significantly (p < 0.05). The surface antigens of CD8+ TRM cells had no significant difference between the control group and the model group, while compared with the model group, the surface antigens of CD8 (p < 0.05), CD69 (p < 0.05), and CD103 (p < 0.05) in the APS group increased significantly. Moreover, the serum IL-12 (p < 0.05) and IFN-γ (p < 0.01) levels in the APS group increased significantly compared with the model group. Conclusion: Our study suggested that APS could alleviate the symptoms of the mice infected with HSV-1, and CD8+ TRM cells in the skin lesions and the levels of IL-12 and IFN-γ in the serum of mice with HSV-1 infection increased after the APS treatment, of which the specific underlying mechanism requires further experiments to clarify. In addition, the antiviral effect of APS might be worthy of further development and utilization.
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The stability of aggregates is of great significance to evaluate water and soil environment in regions plan-ting economic fruit forest. We explored the effects of economic fruit forest types on the structure and stability of soil aggregates in the 0-50 cm soil layer from 5-year-old Amygdalus persica, Pyrus sorotina, Citrus reticulata, Camellia oleifera and Actinidia chinensis forests in the hilly area in northern Hunan. The content, distribution characteristics and stability indices of soil aggregates from each economic fruit forest were quantitatively analyzed by the Shavinov method. The results showed that most soil aggregates were mechanically stable, with a minimum content of 92.3%. After wet sieving, the size of water-stable aggregates in the soil from Camellia oleifera forest was mainly >2 mm, accounting for 55.9% of the total aggregates. The 0.25-2 mm aggregates were the dominant particles in the A. persica, P. sorotina, C. reticulata and A. chinensis forest soils, with contributions higher than 43.6%. The mean weight diameter (MWD) and the geometric mean diameter (GMD) of soil aggregates for the five economic fruit forest types ranged from 1.10 to 3.19 mm and 0.61 to 2.28 mm, respectively. Furthermore, the percentages of soil aggregate destruction (PAD) and fractal dimension (D) were in the range of 2.9%-37.3% and 2.30-2.68, respectively. With the increases of soil depth, the stability of soil aggregates from A. persica, C. oleifera and A. chinensis forest soils became worse; MWD and GMD decreased by 1.7%-57.7% and 4.5%-65.8%, respectively; PAD and D increased by 0.4%-17.3% and 1.6%-11.1%, respectively. The effects of economic fruit forest types on the stability of soil aggregates decreased with increasing soil depth. Based on the stability indices, aggregate stability from five economic fruit forests followed the order of C. oleifera > A. chinensis > P. sorotina > C. reticulata > A. persica. The type of economic fruit forest improved the stability of soil structure mainly by affecting the content of large-size aggregates. In terms of improving the distribution and stability of soil aggregates, it was suggested that C. oleifera should be given the top priority as the economic fruit forest in the subtropical hilly area, followed by A. chinensis. Whereas A. persica planting might reduce the degree of soil agglomeration, thus, the protective measures of soil loss should be considered during planting. Our results could provide theoretical basis and application guidance for the development, utilization, and ecological management of economic fruit forests in subtropical hilly areas.
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Carbono , Solo , Carbono/análise , China , Florestas , Frutas/química , Solo/química , ÁguaRESUMO
This work presents an efficient and facile strategy to prepare an α-amylase bioreactor. As enzymes are quite large to be immobilized inside metal-organic frameworks (MOFs), the tertiary and quaternary structures of α-amylase were first disrupted using a combination of urea, dithiothreitol (DTT), and iodoacetamide (IAA). After losing its tertiary structure, the unfolded proteins can now penetrate into the microporous MOFs, affording fragmented α-amylase@MOF bioreactors. Among the different MOFs evaluated, UiO-66 gave the most promising potential due to the size-matching effect of the α-helix of the fragmented α-amylase with the pore size of UiO-66. The prepared bioreactor exhibited high yields of small carbohydrate (maltose) even when reused up to 15 times (>80% conversion).
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In this paper, we describe the facile preparation of a chiral catalyst by the combination of the amino acid, l-proline (Pro), and the enzyme, porcine pancreas lipase (PPL), immobilized on a microporous metal-organic framework (PPL-Pro@MOF). The multipoint immobilization of PPL onto the MOF is made possible with the aid of Pro, which also provided a chiral environment for enhanced enantioselectivity. The application of the microporous MOF is pivotal in maintaining the catalytic activity of PPL, wherein it prevented the leaching of Pro during the catalytic reaction, leading to the enhanced activity of PPL. The prepared biocatalyst was applied in asymmetric carbon-carbon bond formation, demonstrating the potential of this simple approach for chemical transformations.