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Agricultural practices significantly contribute to greenhouse gas (GHG) emissions, necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production. Plastic film mulching is commonly used in the Loess Plateau region. Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity. Combining these techniques represents a novel agricultural approach in semi-arid areas. However, the impact of this integration on soil carbon storage (SOCS), carbon footprint (CF), and economic benefits has received limited research attention. Therefore, we conducted an eight-year study (2015-2022) in the semi-arid northwestern region to quantify the effects of four treatments [urea supplied without plastic film mulching (CK-U), slow-release fertilizer supplied without plastic film mulching (CK-S), urea supplied with plastic film mulching (PM-U), and slow-release fertilizer supplied with plastic film mulching (PM-S)] on soil fertility, economic and environmental benefits. The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions (≥71.97%). Compared to other treatments, PM-S increased average grain yield by 12.01%-37.89%, water use efficiency by 9.19%-23.33%, nitrogen accumulation by 27.07%-66.19%, and net return by 6.21%-29.57%. Furthermore, PM-S decreased CF by 12.87%-44.31% and CF per net return by 14.25%-41.16%. After eight years, PM-S increased SOCS (0-40 cm) by 2.46%, while PM-U decreased it by 7.09%. These findings highlight the positive effects of PM-S on surface soil fertility, economic gains, and environmental benefits in spring maize production on the Loess Plateau, underscoring its potential for widespread adoption and application.
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Agricultura , Pegada de Carbono , Fertilizantes , Plásticos , Zea mays , Zea mays/crescimento & desenvolvimento , Agricultura/métodos , China , Solo/química , Gases de Efeito Estufa/análise , Nitrogênio/análiseRESUMO
It is very important to clarify the optimization method of the rock-like material ratio for accurately characterizing mechanical properties similar to the original rock. In order to explore the optimal ratio of rock-like materials in gneissic granite, the water-paste ratio, iron powder content and coarse sand content were selected as the influencing factors of the ratio. An orthogonal test design and sensitivity analysis of variance were used to obtain the significant influencing factors of the ratio factors on seven macroscopic mechanical parameters, including compressive strength σc, tensile strength σt, shear strength τf, elastic modulus E, Poisson's ratio ν, internal friction angle φ and cohesion c. A multivariate linear regression equation was constructed to obtain the quantitative relationship between the significant ratio factors and the macroscopic mechanical parameters. Finally, a rock-like material ratio optimization program based on genetic algorithm inversion was written. The results show that the water-paste ratio had extremely significant effects on σc, σt, τf, E, ν and c. The iron powder content had a highly significant effect on σc, σt, τf and c, and it had a significant effect on ν and φ. Coarse sand content had a significant effect on σc, E and c. The multiple linear regression model has good reliability after testing, which can provide theoretical support for predicting the macroscopic mechanical parameters of rock-like materials to a certain extent. After testing, the ratio optimization program works well. When the water-paste ratio is 0.5325, the iron powder content is 3.975% and the coarse sand content is 15.967%, it is the optimal ratio of rock-like materials.
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Drought has a significant impact on crop growth and productivity, highlighting the critical need for precise and timely soil moisture estimation to mitigate agricultural losses. This study focuses on soil moisture retrieval in northern Hebei Province during July 2012, utilizing eight widely employed remote sensing drought indices derived from MODIS satellite data. These indices were cross-referenced with measured soil moisture levels for analysis. Based on their correlation coefficients, a composite remote sensing drought index set comprising six indices was identified. Furthermore, a radial basis function neural network (RBFNN) was employed to estimate soil relative humidity. The accuracy evaluation of the soil moisture estimation model, which integrates multiple remote sensing drought indices and the RBFNN, demonstrated clear superiority over models relying on single drought indices. The model achieved an average estimation accuracy of 87.54 % for soil relative humidity at a depth of 10 cm (SM10) and 87.36 % for a 20 cm depth (SM20). The root mean square errors (RMSE) for the test sets were 0.093 and 0.092, respectively. Validation results for July 2013 indicated that the inversion accurately reflected the actual soil moisture conditions, effectively capturing dynamic moisture changes. These results fully verify the reliability and practicability of the model. These findings introduce a novel approach to local agricultural soil moisture estimation, with significant implications for enhancing agricultural water resource management and decision-making processes.
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The subsidence of the earth's surface in mining areas is characterized by fast speed and large gradients. Conventional small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) monitoring can significantly underestimate results, making it challenging to capture the surface's temporal subsidence features. In this context, this paper proposes a method for monitoring subsidence in mining areas. It utilizes a phase unwrapping network (PUNet) and a fused Weibull model within the SBAS-InSAR framework to address nonlinear and large-gradient subsidence. The basic principle of this method is to first process the SAR images using the small baseline method to obtain the differential interferogram, utilizing the PUNet to obtain reliable large-gradient unwrapped phases. Next, the Weibull model parameters of each pixel are calculated based on the unwrapped phase, and the temporal subsidence of each point on the surface is determined using the calculated parameters. This method introduces a nonlinear model into the SBAS-InSAR solution, which is more consistent with the subsidence characteristics of mining areas. Through experimentation in a backfilled mining working face, the proposed method in this paper yields superior monitoring results compared to conventional approaches.
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Monitoramento Ambiental , Mineração , Monitoramento Ambiental/métodos , Modelos Teóricos , RadarRESUMO
The transient stability assessment based on machine learning faces challenges such as sample data imbalance and poor generalization. To address these problems, this paper proposes an intelligent enhancement method for real-time adaptive assessment of transient stability. In the offline phase, a convolutional neural network (CNN) is used as the base classifier. A model training method based on contrastive learning is introduced, aiming to increase the spatial distance between positive and negative samples in the mapping space. This approach effectively improves the accuracy of the model in recognizing unbalanced samples. In the online phase, when real data with different distribution characteristics from the offline data are encountered, an active transfer strategy is employed to update the model. New system samples are obtained through instance transfer from the original system, and an active sampling strategy considering uncertainty is designed to continuously select high-value samples from the new system for labeling. The model parameters are then updated by fine-tuning. This approach drastically reduces the cost of updating while improving the model's adaptability. Experiments on the IEEE39-node system verify the effectiveness of the proposed method.
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Implementing continue straw returning practices and optimizing nitrogen application can mitigate nitrogen losses and enhance nitrogen use efficiency (NUE) in dryland. 15N-labeled technique offers a robust approach for tracking fertilizer nitrogen fate and assessing nitrogen use efficiency. Based on the continue (>6 yr) experiment, we conducted a two-year experiment (2020 and 2021) to evaluate the effects of straw returning and nitrogen management under plastic film mulching on 15N recovery rates, N2O emissions and maize yield with three treatments: no straw returning with 225 kg N·ha-1 under plastic film mulching (RP-N225), straw returning with 225 kg N·ha-1 under plastic film mulching (RPS-N225), and straw returning with 20% nitrogen reduction (180 kg N·ha-1) under plastic film mulching (RPS-N180). After six years, both continue straw returning with plastic film mulching increased uptake of fertilizer nitrogen, had higher 15N recovery rates than RP-N225, leading to increased 15N accumulation in grain and aboveground biomass, ultimately enhancing yield. The RPS-N225 treatment exhibited the highest spring maize yield and nitrogen harvest index. The RPS-N180 treatment significantly increased maize yield more than RP-N225 and had the highest NUE, partial factor productivity of nitrogen fertilizer, and nitrogen uptake efficiency, with improvements ranging from 1.7 to 2.4%, 19.3-29.6%, and 17.3-27.5%, respectively, compared to the other treatments. Moreover, RPS-N225 resulted in significantly higher cumulative N2O emissions and yield-scaled N2O emissions than the other treatments, whereas the RPS-N180 treatment significantly decreased yield-scaled N2O emissions compared to RP-N225. Hence, combining continue straw returning with appropriate nitrogen reduction can effectively increase maize yield and yield-scaled N2O emissions. By offering insights into optimizing nitrogen fertilizer management after continue maize straw return, this study is contributed to widespread adoption of straw return practices and sustainable agricultural development in semi-arid areas.
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Agricultura , Fertilizantes , Nitrogênio , Zea mays , Zea mays/metabolismo , Zea mays/crescimento & desenvolvimento , Nitrogênio/metabolismo , Agricultura/métodos , Biomassa , Solo/químicaRESUMO
Cancer immunotherapy is developing as the mainstream strategy for treatment of cancer. However, the interaction between the programmed cell death protein-1 (PD-1) and the programmed death ligand 1 (PD-L1) restricts T cell proliferation, resulting in the immune escape of tumor cells. Recently, immune checkpoint inhibitor therapy has achieved clinical success in tumor treatment through blocking the PD-1/PD-L1 checkpoint pathway. However, the presence of M2 tumor-associated macrophages (TAMs) in the tumor microenvironment (TME) will inhibit antitumor immune responses and facilitate tumor growth, which can weaken the effectiveness of immune checkpoint inhibitor therapy. The repolarization of M2 TAMs into M1 TAMs can induce the immune response to secrete proinflammatory factors and active T cells to attack tumor cells. Herein, hollow iron oxide (Fe3O4) nanoparticles (NPs) were prepared for reprogramming M2 TAMs into M1 TAMs. BMS-202, a small-molecule PD-1/PD-L1 inhibitor that has a lower price, higher stability, lower immunogenicity, and higher tumor penetration ability compared with antibodies, was loaded together with pH-sensitive NaHCO3 inside hollow Fe3O4 NPs, followed by wrapping with macrophage membranes. The formed biomimetic FBN@M could produce gaseous carbon dioxide (CO2) from NaHCO3 in response to the acidic TME, breaking up the macrophage membranes to release BMS-202. A series of in vitro and in vivo assessments revealed that FBN@M could reprogram M2 TAMs into M1 TAMs and block the PD-1/PD-L1 pathway, which eventually induced T cell activation and the secretion of TNF-α and IFN-γ to kill the tumor cells. FBN@M has shown a significant immunotherapeutic efficacy for tumor treatment.
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Inibidores de Checkpoint Imunológico , Imunoterapia , Animais , Camundongos , Inibidores de Checkpoint Imunológico/química , Inibidores de Checkpoint Imunológico/farmacologia , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/terapia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/imunologia , Microambiente Tumoral/efeitos dos fármacos , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Linhagem Celular Tumoral , Nanopartículas Magnéticas de Óxido de Ferro/química , Feminino , Macrófagos Associados a Tumor/efeitos dos fármacos , Macrófagos Associados a Tumor/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/metabolismoRESUMO
The decline in global plant diversity has raised concerns about its implications for carbon fixation and global greenhouse gas emissions (GGE), including carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). Therefore, we conducted a comprehensive meta-analysis of 2103 paired observations, examining GGE, soil organic carbon (SOC) and plant carbon in plant mixtures and monocultures. Our findings indicate that plant mixtures decrease soil N2O emissions by 21.4% compared to monocultures. No significant differences occurred between mixtures and monocultures for soil CO2 emissions, CH4 emissions or CH4 uptake. Plant mixtures exhibit higher SOC and plant carbon storage than monocultures. After 10 years of vegetation development, a 40% reduction in species richness decreases SOC content and plant carbon storage by 12.3% and 58.7% respectively. These findings offer insights into the intricate connections between plant diversity, soil and plant carbon storage and GGE-a critical but previously unexamined aspect of biodiversity-ecosystem functioning.
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Biodiversidade , Carbono , Gases de Efeito Estufa , Plantas , Solo , Solo/química , Gases de Efeito Estufa/análise , Carbono/metabolismo , Carbono/análise , Plantas/metabolismo , Óxido Nitroso/análise , Óxido Nitroso/metabolismo , Ecossistema , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análise , Metano/metabolismo , Efeito EstufaRESUMO
Understanding the responses of soybean rhizosphere and functional microbiomes in intercropping scenarios holds promise for optimizing nitrogen utilization in legume-based intercropping systems. This study investigated three cropping layouts under film mulching: sole soybean (S), soybean-maize intercropping in one row (IS), and soybean-maize intercropping in two rows (IIS), each subjected to two nitrogen levels: 110 kg N ha-1 (N110) and 180 kg N ha-1 (N180). Our findings reveal that cropping patterns alter bacterial and nifh communities, with approximately 5 % of soybean rhizosphere bacterial amplicon sequence variants (ASVs) and 42 % of rhizosphere nifh ASVs exhibiting altered abundances (termed sensitive ASVs). Root traits and soil properties shape these communities, with root traits exerting greater influence. Sensitive ASVs drive microbial co-occurrence networks and deterministic processes, predicting 85 % of yield variance and 78 % of partial factor productivity of nitrogen, respectively. These alterations impact bacterial and nifh diversity, complexity, stability, and deterministic processes in legume-based intercropping systems, enhancing performance in terms of yield, nitrogen utilization efficiency, land equivalent ratio, root nodule count, and nodule dry weight under IIS patterns with N110 compared to other treatments. Our findings underscore the importance of field management practices in shaping rhizosphere-sensitive ASVs, thereby altering microbial functions and ultimately impacting the productivity of legume-based intercropping systems. This mechanistic understanding of soybean rhizosphere microbial responses to intercropping patterns offers insights for sustainable intercropping enhancements through microbial manipulation.
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Agricultura , Glycine max , Microbiota , Rizosfera , Microbiologia do Solo , Glycine max/microbiologia , Glycine max/crescimento & desenvolvimento , Agricultura/métodos , Nitrogênio/metabolismo , Produção Agrícola/métodos , Raízes de Plantas/microbiologia , Bactérias/metabolismoRESUMO
Epigenomic imbalance drives abnormal transcriptional processes, promoting the onset and progression of cancer. Although defective gene regulation generally affects carcinogenesis and tumor suppression networks, tumor immunogenicity and immune cells involved in antitumor responses may also be affected by epigenomic changes, which may have significant implications for the development and application of epigenetic therapy, cancer immunotherapy, and their combinations. Herein, we focus on the impact of epigenetic regulation on tumor immune cell function and the role of key abnormal epigenetic processes, DNA methylation, histone post-translational modification, and chromatin structure in tumor immunogenicity, and introduce these epigenetic research methods. We emphasize the value of small-molecule inhibitors of epigenetic modulators in enhancing antitumor immune responses and discuss the challenges of developing treatment plans that combine epigenetic therapy and immunotherapy through the complex interaction between cancer epigenetics and cancer immunology.
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Acute kidney injury (AKI) is a heterogeneous, high-mortality clinical syndrome with diverse pathogenesis and prognosis, but it lacks the effective therapy clinically. Its pathogenesis is associated with production of reactive oxygen/nitrogen species and infiltration of inflammatory cells. To overcome these pathogenic factors and improve the therapeutic efficiency, we synthesized triptolide-loaded mesoscale polydopamine melanin-mimetic nanoparticles (MeNP4TP) as the antioxidant plus anti-inflammatory therapeutic platform to synergistically scavenge reactive oxygen/nitrogen species (RONS), inhibit the activity of macrophages and dendritic cells, and generate Treg cells for AKI therapy. It was demonstrated that mesoscale size was beneficial for MeNP4TP to specifically accumulate at renal tubule cells, and MeNP4TP could significantly attenuate oxidative stress, reduce proinflammatory immune cells in renal, and repair renal function in cisplatin-induced AKI mouse model. MeNP4TP might be a potential candidate to inhibit oxidative damages and inflammatory events in AKI.
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BACKGROUND: Adenocarcinoma of the esophagogastric junction has a center of origin within 5 cm of the esophagogastric junction. Surgical resection remains the main treatment. A transthoracic approach is recommended for Siewert I adenocarcinoma of the esophagogastric junction and a transabdominal approach is recommended for Siewert III adenocarcinoma of the esophagogastric junction. However, there is a need to determine the optimal surgical approach for Siewert II adenocarcinoma of the esophagogastric junction to improve lung function and the prognosis of patients. AIM: To investigate and compare the surgical effects, postoperative changes in pulmonary function, and prognoses of two approaches to treating combined esophagogastric cancer. METHODS: One hundred and thirty-eight patients with combined esophagogastric cancer treated by general and thoracic surgeries in our hospital were selected. They were divided into group A comprising 70 patients (transabdominal approach) and group B comprising 68 patients (transthoracic approach) based on the surgical approach. The indexes related to surgical trauma, number of removed lymph nodes, indexes of lung function before and after surgery, survival rate, and survival duration of the two groups were compared 3 years after surgery. RESULTS: The duration of surgery, length of hospital stay, and postoperative drainage duration of the patients in group A were shorter than those of the patients in group B, and the volume of blood loss caused by surgery was lower for group A than for group B (P < 0.05). At the one-month postoperative review, the first second, maximum ventilation volume, forceful lung volume, and lung volume values were higher for group A than for group B (P < 0.05). Preoperatively, the QLQ-OES18 scale scores of the patients in group A were higher than those in group B on re-evaluation at 3 mo postoperatively (P < 0.05). The surgical complication rate of the patients in group A was 10.00%, which was lower than that of patients in group B, which was 23.53% (P < 0.05). CONCLUSION: Transabdominal and transthoracic surgical approaches are comparable in treating combined esophagogastric cancer; however, the former results in lesser surgical trauma, milder changes in pulmonary function, and fewer complications.
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Premetastatic niche (PMN) is a prerequisite for tumor metastasis. Destruction of PMN can significantly suppress the tumor metastasis. Bone marrow-derived cells are usually recruited into the premetastatic organs to support PMN formation, which can be orchestrated by tumor-derived secreted factors. Neutrophils can chemotactically migrate towards the inflammatory sites and consume tumor-derived secreted factors, capable of acting as therapeutic agents for a broad-spectrum suppression of PMN formation and metastasis. However, neutrophils in response to inflammatory signals can release neutrophil extracellular traps (NETs), promoting the tumor metastasis. Herein, live neutrophils are converted into dead neutrophils (C NE) through a quick-frozen process to maintain PMN-targeting and tumor-derived secreted factor-consuming abilities but eliminate NET-releasing shortcomings. Considering macrophages-regulated remodeling of the extracellular matrix in PMN, bacterial magnetosomes (Mag) are further hitchhiked on the surface of C NE to form C NEMag , which can repolarize macrophages from M2 to M1 phenotype for further disruption of PMN formation. A series of in vitro and in vivo assessments have been applied to confirm the effectiveness of C NEMag in suppression of PMN formation and metastasis. This study presents a promising strategy for targeted anti-metastatic therapy in clinics.
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Armadilhas Extracelulares , Magnetossomos , Neoplasias , Humanos , Neutrófilos , Fenótipo , Neoplasias/patologiaRESUMO
Bladder cancer (BC), such as non-muscle invasive bladder cancer (NMIBC), has a significantly high recurrence rate even after intravesical therapy because traditional intravesical chemotherapeutic drugs have short retention time in the bladder and lack efficient uptake in BC cells. Pollen structure usually shows potent adhesion ability to tissue surfaces, different from traditional electronic interaction or covalent binding. 4-Carboxyphenylboric acid (CPBA) has high affinity to sialic acid residues that are overexpressed on BC cells. In the present study, hollow pollen silica (HPS) nanoparticles (NPs) were prepared and modified with CPBA to form CHPS NPs, which could be further loaded with pirarubicin (THP) to form THP@CHPS NPs. THP@CHPS NPs showed high adhesion to skin tissues and could be more efficiently internalized by a mouse bladder cancer cell line (MB49) than THP, inducing more significant apoptotic cells. After intravesical instillation into a BC mouse model through an indwelling catheter, THP@CHPS NPs could more significantly accumulate at the bladder than THP at 24 h post-instillation, and after 8 days of intravesical treatments, magnetic resonance imaging (MRI) revealed that the bladders treated with THP@CHPS NPs showed more smooth bladder lining and more reduction in size and weights than those with THP. Moreover, THP@CHPS NPs exhibited excellent biocompatibility. THP@CHPS NPs hold great potential for intravesical treatment of bladder cancer.
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Antineoplásicos , Nanopartículas , Neoplasias da Bexiga Urinária , Animais , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/metabolismo , Neoplasias da Bexiga Urinária/patologia , Doxorrubicina/uso terapêutico , Bexiga Urinária/metabolismo , Administração IntravesicalRESUMO
Induction of immunogenic cell death (ICD) by hyperthermia can initiate adaptive immune responses, emerging as an attractive strategy for tumor immunotherapy. However, ICD can induce proinflammatory factor interferon-γ (IFN-γ) production, leading to indoleamine 2,3-dioxygenase 1 (IDO-1) activation and an immunosuppressive tumor microenvironment, which dramatically reduces the ICD-triggered immunotherapeutic efficacy. Herein, we developed a bacteria-nanomaterial hybrid system (CuSVNP20009NB) to systematically modulate the tumor immune microenvironment and improve tumor immunotherapy. Attenuated Salmonella typhimurium (VNP20009) that can chemotactically migrate to the hypoxic area of the tumor and repolarize tumor-associated macrophages (TAMs) was employed to intracellularly biosynthesize copper sulfide nanomaterials (CuS NMs) and extracellularly hitchhike NLG919-embedded and glutathione (GSH)-responsive albumin nanoparticles (NB NPs), forming CuSVNP20009NB. After intravenous injection into B16F1 tumor-bearing mice, CuSVNP20009NB could accumulate in tumor tissues and repolarize TAMs from the immunosuppressive M2 to immunostimulatory M1 phenotype and release NLG919 from extracellular NB NPs to inhibit IDO-1 activity. Under further near infrared laser irradiation, intracellular CuS NMs of CuSVNP20009NB could photothermally induce ICD including calreticulin (CRT) expression and high mobility group box 1 (HMGB-1) release, promoting intratumoral infiltration of cytotoxic T lymphocytes. Finally, CuSVNP20009NB with excellent biocompatibility could systematically augment immune responses and significantly inhibit tumor growth, holding great promise for tumor therapy.
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Nanopartículas , Nanoestruturas , Neoplasias , Animais , Camundongos , Nanoestruturas/uso terapêutico , Neoplasias/terapia , Nanopartículas/uso terapêutico , Linfócitos T Citotóxicos , Imunidade , Microambiente TumoralRESUMO
Lettuce (Lactuca sativa) is a leafy vegetable that belongs to the family Asteraceae. It is widely cultivated and consumed around the world. In May 2022, lettuce plants (cv. 204) showing soft rot symptoms were observed in greenhouses in Fuhai District (25°18'N, 103°6'E), Kunming City, Yunnan Province, China. The disease incidence in three greenhouses (0.3 ha in size) was between 10% to 15%. The lower parts of the outer leaves showed brown and water-soaked symptoms, but at the same time the roots were asymptomatic. Sclerotinia species can cause soft decay on lettuce leaves, known as lettuce drop, which can produce symptoms partially resembling those of bacterial soft rot (Subbarao 1998). The absence of white mycelium or black sclerotia on the leaf surfaces of diseased plants indicated that Sclerotinia species were not responsible for the disease. Instead, it is more likely that bacterial pathogens were the cause. Fourteen diseased plants were sampled from three greenhouses, and potential pathogens were isolated from the leaf tissues of six plant individuals. Leaf samples were cut into pieces ca. 0.5 cm in length. The pieces were then surface-sterilized by dipping in 75% ethanol for 60 sec, followed by three successive rinses using sterile distilled water. The tissues were immersed in 250 µl of 0.9% saline in 2 mL microcentrifuge tubes and gently pressed down with grinding pestles for 10 sec. The tubes were let stand still for 20 min. Aliquots (20 µl) 100-fold dilutions of the tissue suspensions were plated onto Luria-Bertani (LB) plates and incubated at 28°C for 24 h. Three single colonies were picked from each LB plate and restreaked five times for purity. After purification, eighteen strains were obtained, and nine of these were identified by 16S rDNA sequencing using the universal primer pair 27F/1492R (Weisburg et al. 1991). Six out of nine strains (6/9) belonged to the genus Pectobacterium (OP968950-OP968952, OQ568892- OQ568894), two strains (2/9) belonged to the genus Pantoea (OQ568895 and OQ568896), and one strain (1/9) belonged to Pseudomonas sp. (OQ568897). Since the Pectobacterium strains shared identical 16S rDNA sequence, strains CM22112 (OP968950), CM22113 (OP968951) and CM22132 (OP968952) were selected as representative strains for further testing. The 16S rDNA sequences of Pectobacterium strains were 100% identical to that of the P. polaris strain NIBIO 1392 (NR_159086.1). To identify the strains to the species level, multilocus sequence analysis (MLSA) was performed using sequences of six housekeeping genes acnA, gapA, icdA, mdh, proA and rpoS (OP972517-OP972534) (Ma et al. 2007; Waleron et al. 2008). Phylogenetic analysis showed that the strains clustered with P. polaris type strain NIBIO1006T (Dees et al. 2017). They were all capable of utilizing citrate, which is an important biochemical feature in distinguishing P. polaris from its most closely related sister species P. parvum (Pasanen et al. 2020). Lettuce plants (cv. 204), at the rosette stage, were inoculated with the strains CM22112 and CM22132 by injecting 100 µl of bacterial suspensions (107 CFU·mL-1) into the lower parts of the leaf; for the controls, 100 µl of saline was used instead. Inoculated plants were incubated at room temperature (23°C) and 90% relative humidity. Five days after inoculation, only the bacteria-inoculated lettuce showed severe soft rot symptoms. Similar results were observed in two independent experiments. Bacterial colonies were obtained from the infected lettuce leaves, which showed identical sequences to P. polaris strains CM22112 and CM22132. Therefore, these strains fulfilled Koch's postulates for lettuce soft rot. P. polaris is prevalent on potato in many countries (Dees et al. 2017). To our knowledge, this is the first report of P. polaris causing soft rot on lettuce in China. This disease could seriously affect the appearance and saleability of lettuce. Further research on the epidemiology and management strategies of the disease is needed.
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This study aimed at investigating the effects of phytosterols on the productive performance, egg quality, length of small intestine, and tibia quality in aged laying hens. A total of 960 Dawu Jinfeng commercial laying hens (75 weeks of age) were randomly assigned to three groups. Each group had 16 replicates and every replicate contained four cages (five birds/cage). The control group hens received the basal diet without phytosterols. The hens in the experimental groups received a diet containing phytosterols at concentrations of 20 mg/kg and 40 mg/kg for 7 weeks. The results showed that phytosterols had a linearly increasing effect on egg weight, eggshell surface area, albumen height, and haugh unit at week 5 of experiment (p < 0.05). Supplemental phytosterols linearly and quadratically increased eggshell thickness (p < 0.05). At week 7 of the experiment, dietary supplementation of phytosterols linearly increased egg weight and eggshell weight (p < 0.05). Supplementation of 20 mg/kg, but not 40 mg/kg, phytosterols increased the length of the small intestine. However, dietary phytosterols had no effect on the laying rate, mortality, or liver index (p > 0.1). The results of tibia quality detected by micro-CT also showed no difference in the treatment of phytosterols. Therefore, supplementation with 20 mg/kg phytosterols in the diet improves egg quality and increases the length of small intestine, but has no effects on the quality of the tibia.
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Obesity treatment is a global public health challenge due to inadequate weight loss and weight regain even after endeavors with multimodal treatments. Considering the abundance of resident macrophages in adipose tissues, precise regulation of the interactions between macrophages and adipocytes may provide chances for immunotherapy of obesity. Herein, inspired by the phagocytosis of macrophages to clear apoptotic cells in homeostasis, an immunotherapy strategy for obesity treatment is proposed for the first time through apoptotic camouflage of adipocytes by PA Au BPs to activate macrophages for clearance, where PA Au BPs are gold nanobipyramids engineered with adipose-targeting and apoptotic cell-mimicking functions. During clearance, the macrophage is switched from pro-inflammatory M1 to anti-inflammatory M2, remarkably modulating the immune microenvironment of adipose tissues to prevent weight regain. After inguinal injection with PA Au BPs, the body weights of obese mice are effectively decreased by 24.4% and can be decreased by 33.3% when combined with photothermal lipolysis, and little weight regain is associated with these treatments. This study demonstrates that the strategy of camouflaging adipocytes with apoptotic features holds great potential for obesity immunotherapy.
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Adipócitos , Tecido Adiposo , Animais , Camundongos , Adipócitos/fisiologia , Obesidade , Aumento de Peso , Imunoterapia , Camundongos Endogâmicos C57BLRESUMO
A palladium-catalyzed dearomatizing [2+2+1] spiroannulation of indoles with two molecular internal alkynes is developed in the presence of Cu(OAc)2/O2 as the oxidant, in which a domino sequence including C-H activation of indole followed by consecutive Heck reactions is involved. A range of 3,3'-spiroindolines bearing tetrasubstituted cyclopentadiene moieties and exocyclic CâC bonds at C2 are obtained in moderate to excellent yields.
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Immunotherapy efficacy has been limited by tumor-associated macrophages (TAMs), which are the most abundant immune regulatory cells infiltrating around tumor tissues. The repolarization of pro-tumor M2 TAMs to anti-tumor M1 TAMs is a very promising immunotherapeutic strategy for cancer therapy. In this manuscript, multifunctional 2D iron-based nanosheets (FeNSs) are synthesized via a simple hydrothermal method for the first time, which not only possess photothermal and photodynamic properties, but also can repolarize TAMs from M2 to M1. After modifying with polyethylene glycol and loading with bioreductive prodrug banoxantrone (AQ4N), abbreviated as AP FeNSs, it can effectively repolarize TAMs from M2 to M1 and deliver AQ4N to tumor microenvironment (TME). Moreover, the repolarized M1 TAMs overexpress inducible nitric oxide synthase, which can convert nontoxic AQ4N to cytotoxic AQ4 under hypoxic TME, enabling immunomodulation-activated chemotherapy. A series of in vitro and in vivo results corroborate that AP FeNSs effectively exert photothermal and photodynamic effects and repolarize M2 TAMs to M1 TAMs, releasing inflammatory factors and activating the chemotherapeutic effect, thereby realizing synergistic tumor therapy.