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1.
ChemMedChem ; 19(14): e202400111, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622787

RESUMEN

Abnormally localized nucleic acids (NAs) are considered as pathogen associated molecular patterns (PAMPs) in innate immunity. They are recognized by NAs-specific pattern recognition receptors (PRRs), leading to the activation of associated signaling pathways and subsequent production of type I interferons (IFNs) and pro-inflammatory cytokines, which further trigger the adaptive immunity. Notably, NAs-mediated innate immune activation is highly dependent on the conformation changes, especially the aggregation of PRRs. Evidence indicates that the characteristics of NAs including their length, concentration and even spatial structure play essential roles in inducing the aggregation of PRRs. Therefore, nucleic acid materials (NAMs) with high valency of NAs and high-order structures hold great potential for activating innate and adaptive immunity, making them promising candidates for cancer immunotherapy. In recent years, a variety of NAMs have been developed and have demonstrated significant efficacy in achieving satisfactory anti-tumor immunity in multiple mouse models, exhibiting huge potential for clinical application in cancer treatment. This review aims to discuss the mechanisms of NAMs-mediated innate immune response, and summarize their applications in cancer immunotherapy.


Asunto(s)
Inmunidad Innata , Inmunoterapia , Neoplasias , Ácidos Nucleicos , Inmunidad Innata/efectos de los fármacos , Humanos , Neoplasias/inmunología , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Ácidos Nucleicos/química , Ácidos Nucleicos/farmacología , Animales
2.
Nat Commun ; 14(1): 7766, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38012167

RESUMEN

Using highly sensitive and selective in situ techniques to investigate the dynamics of intermediates formation is key to better understand reaction mechanisms. However, investigating the early stages of solid-state reactions/transformations is still challenging. Here we introduce in situ fluorescence spectroscopy to observe the evolution of intermediates during a two-step [2 + 2] photocycloaddition process in a coordination polymer platform. The structural changes and kinetics of each step under ultraviolet light irradiation versus time are accompanied by the gradual increase-decrease of intensity and blue-shift of the fluorescence spectra from the crystals. Monitoring the fluorescence behavior using a laser scanning confocal microscope can directly visualize the inhomogeneity of the photocycloaddition reaction in a single crystal. Theoretical calculations allow us to rationalize the fluorescence behavior of these compounds. We provide a convenient strategy for visualizing the solid-state photocycloaddition dynamics using fluorescence spectroscopy and open an avenue for kinetic studies of a variety of fast reactions.

3.
Environ Res ; 237(Pt 1): 116881, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37595829

RESUMEN

Agricultural land is the most basic input factor for agricultural production and an essential component of terrestrial ecosystems, which plays a vital role in achieving carbon neutrality. Giving full play to the carbon-neutral contribution of agricultural land is a crucial part of China's economic transformation and green development. It incorporates carbon and pollution emissions from agricultural land use into the unexpected outputs of the Green and Low-carbon Utilization Efficiency of Agricultural Land (GLUEAL) evaluation system. The study utilized several advanced analytical tools, including the super-efficient Slacks-Based Measure (SBM) model, Exploratory Spatial-Temporal Data Analysis (ESTDA) method, Geodetector, and Geographically and Temporally Weighted Regression (GTWR) model. The objective was to examine the spatial-temporal evolution of GLUEAL and identify the factors that influenced it in all 31 provinces of China from 2005 to 2020. The results show that: (1) The overall spatial-temporal evolution of GLUEAL showed an increasing trend, but the disparity between provinces and regions became wider. (2) Most provinces have not yet made significant spatial and temporal jumps. They have high spatial cohesion with specific "path-dependent" characteristics. (3) The Geodetector results reveal that the Number of Rural Labor Force with Higher Education (NRLFHE) and Technology Support for Agriculture (TSA) have insufficient explanatory power on average for GLUEAL. Agricultural Economic Development Level (AEDL), Urbanization Level (UL), Multiple Crop Index (MCI), Planting Structure (PS), Degree of Crop Damage (DCD), Financial support for agriculture (FSA), and Agricultural mechanization level (AML) had stronger explanatory power on average for GLUEAL and were important factors influencing GLUEAL levels. (4) The average influence of AEDL, UL, FSA, and AML on GLUEAL changed from negative to positive. The average influence of MCI and DCD on GLUEAL was negative, and the average influence of PS on GLUEAL changed from positive to negative. This study provides a comprehensive description of the spatial and temporal evolution of GLUEAL in China. It reveals the key factors influencing GLUEAL and analyzes their spatial variations and impact patterns. These findings offer robust evidence for government policymakers to formulate policy measures for sustainable agricultural development and optimized resource allocation, promoting the transformation of agricultural land towards green and low-carbon practices and advancing the achievement of sustainable development goals.

4.
Angew Chem Int Ed Engl ; 62(33): e202306719, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37335924

RESUMEN

Due to its high reactivity and oxidative strength, singlet oxygen (1 O2 ) is used in a variety of fields including organic synthesis, biomedicine, photodynamic therapy and materials science. Despite its importance, the controlled trapping and release of 1 O2 is extremely challenging. Herein, we describe a one-dimensional coordination polymer, CP1, which upon irradiation with visible light, transforms 3 O2 (triplet oxygen) to 1 O2 . CP1 consists of CdII centers bridged by 9,10-bis((E)-2-(pyridin-4-yl)vinyl)anthracene ligands which undergo a [4+2] cycloaddition reaction with 1 O2 , resulting in the generation of CP1-1 O2 . Using microwave irradiation, CP1-1 O2 displays efficient release of 1 O2 , over a period of 30 s. In addition, CP1 exhibits enhanced fluorescence and has an oxygen detection limit of 97.4 ppm. Theoretical calculations reveal that the fluorescence behaviour is dominated by unique through-space conjugation. In addition to describing a highly efficient approach for the trapping and controlled release of 1 O2 , using coordination polymers, this work also provides encouragement for the development of efficient fluorescent oxygen sensors.

5.
Front Microbiol ; 13: 970563, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36204629

RESUMEN

The effects of brewers' spent grain (BSG) diets on the fatty liver deposition and the cecal microbial community were investigated in a total of 320 healthy 5-day-old Landes geese. These geese were randomly and evenly divided into 4 groups each containing 8 replicates and 10 geese per replicate. These four groups of geese were fed from the rearing stage (days 5-60) to the overfeeding stage (days 61-90). The Landes geese in group C (control) were fed with basal diet (days 5-90); group B fed first with basal diet in the rearing stage and then basal diet + 4% BSG in the overfeeding stage; group F first with basal diet + 4% BSG during the rearing stage and then basal diet in the overfeeding stage; and group W with basal diet + 4% BSG (days 5-90). The results showed that during the rearing stage, the body weight (BW) and the average daily gain (ADG) of Landes geese were significantly increased in groups F and W, while during the overfeeding stage, the liver weights of groups W and B were significantly higher than that of group C. The taxonomic structure of the intestinal microbiota revealed that during the overfeeding period, the relative abundance of Bacteroides in group W was increased compared to group C, while the relative abundances of Escherichia-Shigella and prevotellaceae_Ga6A1_group were decreased. Results of the transcriptomics analysis showed that addition of BSG to Landes geese diets altered the expression of genes involved in PI3K-Akt signaling pathway and sphingolipid metabolism in the liver. Our study provided novel experimental evidence based on the cecal microbiota to support the application of BSG in the regulation of fatty liver deposition by modulating the gut microbiota in Landes geese.

6.
Front Microbiol ; 12: 725196, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34764942

RESUMEN

To explore the feasibility of using fermented Chinese herbal mixture Zhihuasi Tk (Z. Tk) supplementation to increase the swine production, the protective effect of dietary supplementation with Z. Tk on the intestinal oxidative stress model and the regulation of both growth performance and intestinal microbiota of weaned piglets were investigated in vitro. Our results showed that the addition of Z. Tk increased the cell viability, prevented the decrease of glutathione peroxidase, and significantly increased the total antioxidant capacity and reduced the damage caused by H2O2 to the tight junction proteins of the porcine small intestinal epithelial cell line (IPEC-J2). Furthermore, weaned piglets supplemented with either 2 kg/ton zinc oxide (ZnO) or 4 kg/ton of Z. Tk in the diet increased body weight as well as average daily feed intake and daily gain, while the feed conversion rate and diarrhea rate decreased within 0-35 days. Results of the taxonomic structure of the intestinal microbiota showed that, in 21 days after weaning, the Firmicutes/Bacteroidetes ratio in experimental group was increased, while the abundance of beneficial bacteria such, as Lactobacillus, was increased by Z. Tk, showing inhibitory effect on pathogenic bacteria such as members of Proteobacteria. In summary, dietary supplementation with Z. Tk maintained the intestinal microbiota in a favorable state for the host to effectively reduce the abnormal changes in the intestinal microbial structure and improved growth performance of weaned piglets. Therefore, Z. Tk may potentially function as a substitute for ZnO in feed additives for weaned piglets in modern husbandry.

7.
Microorganisms ; 9(2)2021 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-33668643

RESUMEN

Bacillus amyloliquefaciens TL promotes broiler chicken performance by improving nutrient absorption and utilization and reducing intestinal inflammation. In this study, RNA-sequencing (RNA-seq)-based transcriptomes of ileal tissues collected from probiotic-fed and control broiler chickens were analyzed to elucidate the effects of the probiotic B. amyloliquefaciens TL, as a feed additive, on the gut immune function. In total, 475 genes were significantly differentially expressed between the ileum of probiotic-fed and control birds. The expression of genes encoding pyruvate kinase, prothymosin-α, and heat stress proteins was high in the ileum of probiotic-fed birds (FPKM > 500), but not in the control group. The gene ontology functional enrichment and pathway enrichment analyses revealed that the uniquely expressed genes in the control group were mostly involved in immune responses, whereas those in the probiotic group were involved in fibroblast growth factor receptor signaling pathways and positive regulation of cell proliferation. Bacillus amyloliquefaciens TL downregulated the expression of certain proinflammatory factors and affected the cytokine-cytokine receptor interaction pathway. Furthermore, B. amyloliquefaciens TL in broiler diets altered the expression of genes involved in immune functions in the ileum. Thus, it might contribute to improved broiler growth by regulating the immune system and reducing intestinal damage in broilers.

8.
Biomed Res Int ; 2019: 5431354, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31687392

RESUMEN

Probiotics can promote the health and growth performance of animals through modulation of intestinal microbiota. When used as a feed additive, they have the potential to minimize or abolish the use of antibiotics. In this study, we investigated the effect of the probiotic strain Bacillus amyloliquefaciens TL on the growth performance and cecum microflora composition in Cobb 500 broiler chickens. In total, 180 broilers were randomly divided into three groups-each group comprised 4 pens, and each pen contained 15 chickens. The three groups were fed either a control diet, or a diet supplemented with either the antibiotic chlortetracycline or B. amyloliquefaciens TL. Broilers were weighed, and cecum contents were collected on days 7, 14, 21, and 35, respectively. The broilers in both the antibiotic and probiotic groups exhibited significant weight gain compared with controls, exhibiting increases of 16.02% and 13.40%, respectively, after 35 days (P < 0.01). Similarly, the feed conversion ratio (FCR, 1-35 days) of broilers in the chlortetracycline and B. amyloliquefaciens TL groups was lower than that of the controls. HiSeq high-throughput sequencing of 16S rRNA of the cecal microbiota was performed on days 7, 14, 21, and 35, respectively. The Firmicutes/Bacteroidetes ratio was higher in the chlortetracycline and B. amyloliquefaciens TL groups than in the control group on days 14, 21, and 35, and especially on day 21. The prevalence of genera Oscillospira, Ruminococcus, Butyricicoccus, and Faecalibacterium (Firmicutes) was higher in the antibiotic and probiotic groups, while that of Bacteroides, Parabacteroides (Bacteroidetes), and Lactobacillus was higher in the control group. In this study, the changes in the microbiota of the probiotic group were similar to those in the antibiotic group. These results suggest that the probiotic strain B. amyloliquefaciens TL can modulate the cecal microbiota of broilers similar to chlortetracycline.


Asunto(s)
Bacillus amyloliquefaciens/fisiología , Ciego/microbiología , Pollos/microbiología , Microbioma Gastrointestinal/efectos de los fármacos , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Antibacterianos/farmacología , Clortetraciclina/farmacología , Dieta , Suplementos Dietéticos , Masculino , Probióticos/farmacología , ARN Ribosómico 16S , Aumento de Peso/fisiología
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