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1.
J Nanobiotechnology ; 22(1): 268, 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38764056

RESUMEN

The development of cost-effective and eco-friendly fertilizers is crucial for enhancing iron (Fe) uptake in crops and can help alleviate dietary Fe deficiencies, especially in populations with limited access to meat. This study focused on the application of MgFe-layered double hydroxide nanoparticles (MgFe-LDHs) as a potential solution. We successfully synthesized and characterized MgFe-LDHs and observed that 1-10 mg/L MgFe-LDHs improved cucumber seed germination and water uptake. Notably, the application of 10 mg/L MgFe-LDHs to roots significantly increased the seedling emergence rate and growth under low-temperature stress. The application of 10 mg/L MgFe-LDHs during sowing increased the root length, lateral root number, root fresh weight, aboveground fresh weight, and hypocotyl length under low-temperature stress. A comprehensive analysis integrating plant physiology, nutrition, and transcriptomics suggested that MgFe-LDHs improve cold tolerance by upregulating SA to stimulate CsFAD3 expression, elevating GA3 levels for enhanced nitrogen metabolism and protein synthesis, and reducing levels of ABA and JA to support seedling emergence rate and growth, along with increasing the expression and activity of peroxidase genes. SEM and FTIR further confirmed the adsorption of MgFe-LDHs onto the root hairs in the mature zone of the root apex. Remarkably, MgFe-LDHs application led to a 46% increase (p < 0.05) in the Fe content within cucumber seedlings, a phenomenon not observed with comparable iron salt solutions, suggesting that the nanocrystalline nature of MgFe-LDHs enhances their absorption efficiency in plants. Additionally, MgFe-LDHs significantly increased the nitrogen (N) content of the seedlings by 12% (p < 0.05), promoting nitrogen fixation in the cucumber seedlings. These results pave the way for the development and use of LDH-based Fe fertilizers.


Asunto(s)
Frío , Cucumis sativus , Hierro , Plantones , Cucumis sativus/crecimiento & desarrollo , Cucumis sativus/metabolismo , Cucumis sativus/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Plantones/efectos de los fármacos , Hierro/metabolismo , Raíces de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Germinación/efectos de los fármacos , Hidróxidos/farmacología , Hidróxidos/metabolismo , Fertilizantes , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Nanopartículas/química , Estrés Fisiológico , Magnesio/metabolismo
2.
Microbiol Res ; 285: 127748, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38735241

RESUMEN

The rhizosphere system of plants hosts a diverse consortium of bacteria that confer beneficial effects on plant, such as plant growth-promoting rhizobacteria (PGPR), biocontrol agents with disease-suppression activities, and symbiotic nitrogen fixing bacteria with the formation of root nodule. Efficient colonization in planta is of fundamental importance for promoting of these beneficial activities. However, the process of root colonization is complex, consisting of multiple stages, including chemotaxis, adhesion, aggregation, and biofilm formation. The secondary messenger, c-di-GMP (cyclic bis-(3'-5') dimeric guanosine monophosphate), plays a key regulatory role in a variety of physiological processes. This paper reviews recent progress on the actions of c-di-GMP in plant beneficial bacteria, with a specific focus on its role in chemotaxis, biofilm formation, and nodulation.

3.
J Appl Clin Med Phys ; : e14371, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38682540

RESUMEN

PURPOSE: To create and evaluate a three-dimensional (3D) Prompt-nnUnet module that utilizes the prompts-based model combined with 3D nnUnet for producing the rapid and consistent autosegmentation of high-risk clinical target volume (HR CTV) and organ at risk (OAR) in high-dose-rate brachytherapy (HDR BT) for patients with postoperative endometrial carcinoma (EC). METHODS AND MATERIALS: On two experimental batches, a total of 321 computed tomography (CT) scans were obtained for HR CTV segmentation from 321 patients with EC, and 125 CT scans for OARs segmentation from 125 patients. The numbers of training/validation/test were 257/32/32 and 87/13/25 for HR CTV and OARs respectively. A novel comparison of the deep learning neural network 3D Prompt-nnUnet and 3D nnUnet was applied for HR CTV and OARs segmentation. Three-fold cross validation and several quantitative metrics were employed, including Dice similarity coefficient (DSC), Hausdorff distance (HD), 95th percentile of Hausdorff distance (HD95%), and intersection over union (IoU). RESULTS: The Prompt-nnUnet included two forms of parameters Predict-Prompt (PP) and Label-Prompt (LP), with the LP performing most similarly to the experienced radiation oncologist and outperforming the less experienced ones. During the testing phase, the mean DSC values for the LP were 0.96 ± 0.02, 0.91 ± 0.02, and 0.83 ± 0.07 for HR CTV, rectum and urethra, respectively. The mean HD values (mm) were 2.73 ± 0.95, 8.18 ± 4.84, and 2.11 ± 0.50, respectively. The mean HD95% values (mm) were 1.66 ± 1.11, 3.07 ± 0.94, and 1.35 ± 0.55, respectively. The mean IoUs were 0.92 ± 0.04, 0.84 ± 0.03, and 0.71 ± 0.09, respectively. A delineation time < 2.35 s per structure in the new model was observed, which was available to save clinician time. CONCLUSION: The Prompt-nnUnet architecture, particularly the LP, was highly consistent with ground truth (GT) in HR CTV or OAR autosegmentation, reducing interobserver variability and shortening treatment time.

4.
Front Cardiovasc Med ; 11: 1352921, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38500760

RESUMEN

Introduction: The presence of abdominal aortic calcification (AAC) is strongly linked to the development of atherosclerosis and the incidence of morbidity and mortality related to cardiovascular diseases (CVD). Urinary albumin creatinine ratio (UACR) was found related with the increased risk of CVD. The aim of this study is to explore the relationship between the UACR and severe AAC (SAAC). Methods and Results: This study included a total of 2,379 individuals aged over 40 years, and their information was obtained from the National Health and Nutrition Examination Survey conducted (NHANES) in 2013-2014. The measurement of AAC was conducted through dual-energy x-ray absorptiometry and assessed using the Kauppila scoring system. SAAC was characterized by a Kauppila score of 6 or higher. Multivariate regression models were used to analyze the relationship between UACR level and SAAC, with covariate adjustment. In the completely adapted model, the top third subgroup exhibits increased likelihood of SAAC (odds ratio 1.50; 95%CI: 0.98, 2.29; p = 0.030) in contrast to the bottom third subgroup. The subgroup analyses revealed a more pronounced correlation among the older participants (p-value for interaction = 0.013). Discussion: In the United States, SAAC was more likely to occur in adults who had a higher probability of UACR. The use of UACR has the potential to be a valuable method for forecasting the likelihood of SAAC.

5.
Curr Res Food Sci ; 8: 100711, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38524400

RESUMEN

The current study investigated the in vitro probiotic potential of yeast isolated from kombucha, a tea beverage fermented with a symbiotic culture of acetic acid bacteria and yeast. A total of 62 yeast strains were previously isolated from four different commercial kombucha samples sold in New Zealand. Fifteen representative isolates belonging to eight different species were evaluated for their growth under different conditions (temperature, low pH, concentrations of bile salts, and NaCl). Cell surface characteristics, functional and enzymatic activities of the selected strains were also studied in triplicate experiments. Results showed that six strains (Dekkera bruxellensis LBY1, Sachizosaccharomyces pombe LBY5, Hanseniaspora valbyensis DOY1, Brettanomyces anomalus DOY8, Pichia kudraivzevii GBY1, and Saccharomyces cerevisiae GBY2) were able to grow under low-acid conditions (at pH 2 and pH 3) and in the presence of bile salts. This suggests their potential to survive passage through the human gut. All 15 strains exhibited negative enzymatic activity reactions (haemolytic, gelatinase, phospholipase, and protease activities), and thus, they can be considered safe to consume. Notably, two of the fifteen strains (Pichia kudraivzevii GBY1 and Saccharomyces cerevisiae GBY2) exhibited desirable cell surface hydrophobicity (64.60-83.87%), auto-aggregation (>98%), co-aggregation, resistance to eight tested antibiotics (ampicillin, chloramphenicol, colistin sulphate, kanamycin, nalidixic acid, nitrofurantoin, streptomycin, and tetracycline), and high levels of antioxidant activities (>90%). Together, our data reveal the probiotic activities of two yeast strains GBY1 and GBY2 and their potential application in functional food production.

6.
Microorganisms ; 12(3)2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38543667

RESUMEN

Alfalfa (Medicago sativa L.), a forage legume known for its moderate salt-alkali tolerance, offers notable economic and ecological benefits and aids in soil amelioration when cultivated in saline-alkaline soils. Nonetheless, the limited stress resistance of alfalfa could curtail its productivity. This study investigated the salt tolerance and growth-promoting characteristics (in vitro) of four strains of plant growth-promoting rhizobacteria (PGPR) that were pre-selected, as well as their effects on alfalfa at different growth stages (a pot experiment). The results showed that the selected strains belonged to the genera Priestia (HL3), Bacillus (HL6 and HG12), and Paenibacillus (HG24). All four strains exhibited the ability to solubilize phosphate and produce indole-3-acetic acid (IAA) and 1-aminocyclopropane-1-carboxylate (ACC) deaminase. Among them, except for strain HG24, the other strains could tolerate 9% NaCl stress. Treatment with 100 mM NaCl consistently decreased the IAA production levels of the selected strains, but inconsistent changes (either enhanced or reduced) in terms of phosphate solubilization, ACC deaminase, and exopolysaccharides (EPS) production were observed among the strains. During the various growth stages of alfalfa, PGPR exhibited different growth-promoting effects: at the seedling stage, they enhanced salt tolerance through the induction of physiological changes; at the flowering stage, they promoted growth through nutrient acquisition. The current findings suggest that strains HL3, HL6, and HG12 are effective microbial inoculants for alleviating salt stress in alfalfa plants in arid and semi-arid regions. This study not only reveals the potential of indigenous salt-tolerant PGPR in enhancing the salt tolerance of alfalfa but also provides new insights into the mechanisms of action of PGPR.

7.
Chemistry ; 30(24): e202400350, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38407517

RESUMEN

The development of new metal-organic frameworks (MOFs) thin films is important for expanding their functions and applications. Herein, we first report a new kind of MOF thin film by using aggregation-induced emission (AIE) dicarboxyl ligand through a liquid-phase epitaxial (LPE) layer-by-layer (LBL) spraying method (named AIE surface-coordinated metal-organic frameworks thin film, AIE-SURMOF). The obtained AIE-SURMOF Zn4O(TPE)3 (ZnTPE) has highly growth orientation and homogeneous thin film, showing strong fluorescent property. Furthermore, by loading chiral guest in the MOF pore, the formed chiral encapsulated AIE-SURMOF can clearly indicate obvious circularly polarized luminescence performance with glum of 0.01. This study provides new MOF thin film and new strategy for expanding function and application of MOF materials.

8.
Crit Care ; 27(1): 493, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-38102705

RESUMEN

BACKGROUND: Intensive care unit-acquired weakness (ICU-AW) is a prevalent and severe issue among ICU patients. Resistance training and beta-hydroxy-beta-methylbutyrate (HMB) intervention have demonstrated the potential to enhance muscle function in patients with sarcopenia and in older adults. The purpose of this study was to determine whether resistance training and/or HMB administration would improve physical function, muscle strength, and quality of life in medical ICU patients. METHODS: In this multicentre, four-arm, single-blind randomised control trial, a total of 112 adult patients with internal medical diagnoses admitted to the ICU were enrolled. These participants were then randomly assigned to one of four treatment groups: the resistance training group received protocol-based multilevel resistance exercise, the HMB group received 3 g/day of HMBCa, combination group and control groups received standard care, from the ICU to the general ward until discharge. The primary outcomes assessed at discharge included six-minute walking distance (6MWD) and short physical performance battery (SPPB). Secondary outcomes measured included muscle mass, MRC score, grip strength, and health reports quality of life at different time points. Data analysis was performed using a generalised linear mixed model, adhering to the principles of intention-to-treat analysis. RESULTS: Resistance training and combination treatment groups exhibited significant increases in SPPB scores (3.848 and 2.832 points, respectively) compared to the control group and substantial improvements in 6WMD (99.768 and 88.577 m, respectively) (all with P < 0.01). However, no significant changes were observed in the HMB group. Muscle strength, as indicated by MRC and grip strength tests conducted at both ICU and hospital discharge, showed statistically significant improvements in the resistance training and combination groups (P < 0.05). Nevertheless, no significant differences were found between the treatment groups and usual care in terms of 60-day mortality, prevalence of ICU-AW, muscle mass, quality of life, or other functional aspects. CONCLUSIONS: Resistance training with or without beta-hydroxy-beta-methylbutyrate during the entire hospitalisation intervention improves physical function and muscle strength in medical ICU patients, but muscle mass, quality of life, and 60-day mortality were unaffected. TRIAL REGISTRATION: ChiCTR2200057685 was registered on March 15th, 2022.


Asunto(s)
Entrenamiento de Fuerza , Humanos , Suplementos Dietéticos , Unidades de Cuidados Intensivos , Fuerza Muscular , Músculo Esquelético/fisiología , Alta del Paciente , Calidad de Vida , Método Simple Ciego , Adulto
9.
J Nanobiotechnology ; 21(1): 417, 2023 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-37950234

RESUMEN

Layered double hydroxides (LDHs) have been widely used in the field of plant engineering, such as DNA/RNA transformation and enhancing plant disease resistance. However, few studies have examined the direct effects of LDHs on plants and their potential utility as nanofertilizers. In this study, the retention capacity of Cu/Fe-layered double hydroxide nanoparticles (CuFe-LDHs) was assessed by comparative experiments on vegetables. The results showed that the retention of CuFe-LDHs in leafy vegetables was high, such as lettuce. Phenotypic analysis revealed that the fresh and dry weights of lettuce leaves were both increased by spraying 10-100 µg/mL CuFe-LDHs. Using the optimal concentration of 10 µg/mL, we conducted further experiments to elucidate the mechanism of CuFe-LDHs promoting lettuce growth. It was found that the application of CuFe-LDHs had a significant effect on growth and induced physiological, transcriptomic, and metabolomic changes, including an increase in the chlorophyll b content, net photosynthetic rate, and intercellular carbon dioxide concentration, as well as modifications in gene expression patterns and metabolite profiles. This work provides compelling evidence that CuFe-LDHs can efficiently adsorb on the surface of lettuce leaves through hydrogen bonding, promote lettuce growth, mitigate the toxicity of heavy metal ions compared to their raw materials at the same concentration and offer a molecular-scale insight into the response of leafy vegetables to CuFe-LDHs.


Asunto(s)
Metales Pesados , Nanopartículas , Lactuca , Hidróxidos
10.
ACS Nano ; 17(19): 19136-19143, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37740252

RESUMEN

Combining the features of the host-guest system and chirality is an efficient strategy to achieve circularly polarized luminescence (CPL). Herein, well-defined chiral carbon nanodot (chirCND) arrays were confined-synthesized by low-temperature calcination of a chiral amino acid loaded metal-organic framework (MOF) to induce high CPL. An achiral porous pyrene-based MOF NU-1000 thin film as the host template was prepared by a liquid-phase epitaxial layer-by-layer fashion, and chiral amino acids as the carbon sources could be confined in the porous MOF and carbonized to homogeneous and ultrasmall chirCND arrays, resulting in a chirCNDs@NU-1000 thin film (l-CNDsx@NU-1000; x = l-cysteine (cys), l-serine, l-histidine, l-glutamic acid, and l-pyroglutamic acid). The results show the pristine chirCNDs by directly carbonizing chiral amino acids hardly endow them with a CPL property. By contrast, benefiting from the arrayed confinement and coordination interaction between chirCNDs and NU-1000, the chirality transfer on the excited state of chirCNDs@NU-1000 is enabled, leading to strong CPL performance (a high luminescence dissymmetry factor glum of l-CNDscys@NU-1000 thin film reached 1.74 × 10-2). This study of chirCNDs encapsulated in fluorescent MOF thin films provides a strategy for developing uniform chiral carbon nanoarrays and offers chiral host-guest thin-film materials for optical applications.

11.
Parasit Vectors ; 16(1): 280, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37580819

RESUMEN

BACKGROUND: Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is increasing worldwide. Although there is currently no completely curative treatment, helminthic therapy shows certain therapeutic potential for UC. Many studies have found that Trichinella spiralis (T.s) has a protective effect on UC, but the specific mechanism is still unclear. METHODS: Balb/c mice drank dextran sulfate sodium (DSS) to induce acute colitis and then were treated with T.s. In vitro experiments, the LPS combination with ATP was used to induce the pyroptosis model, followed by intervention with crude protein from T.s (T.s cp). Additionally, the pyroptosis agonist of NSC or the pyroptosis inhibitor vx-765 was added to intervene to explore the role of pyroptosis in DSS-induced acute colitis. The degree of pyroptosis was evaluated by western blot, qPCR and IHC, etc., in vivo and in vitro. RESULTS: T.s intervention significantly inhibited NLRP3 inflammasome activation and GSDMD-mediated pyroptosis by downregulating the expression of pyroptosis-related signatures in vitro (cellular inflammatory model) and in vivo (DSS-induced UC mice model). Furthermore, blockade of GSDMD-mediated pyroptosis by the caspase-1 inhibitor vx-765 has a similar therapeutic effect on DSS-induced UC mice with T.s intervention, thus indicating that T.s intervention alleviated DSS-induced UC in mice by inhibiting GSDMD-mediated pyroptosis. CONCLUSION: This study showed that T.s could alleviate the pathological severity UC via GSDMD-mediated pyroptosis, and it provides new insight into the mechanistic study and application of helminths in treating colitis.


Asunto(s)
Colitis Ulcerosa , Colitis , Gasderminas , Enfermedades Inflamatorias del Intestino , Trichinella spiralis , Animales , Ratones , Colitis/inducido químicamente , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Piroptosis
12.
Foods ; 12(12)2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37372525

RESUMEN

Kombucha is a popular sparkling sugared tea, fermented by a symbiotic culture of acetic acid bacteria (AAB) and yeast. The demand for kombucha continues to increase worldwide, mainly due to its perceived health benefits and appealing sensory properties. This study isolated and characterised the dominant AAB and yeast from a starter culture and kombucha broth after 0, 1, 3, 5, 7, 9, 11, and 14 days of fermentation at ambient temperature (22 °C). Yeast and AAB were isolated from the Kombucha samples using glucose yeast extract mannitol ethanol acetic acid (GYMEA) and yeast extract glucose chloramphenicol (YGC) media, respectively. The phenotypic and taxonomic identification of AAB and yeast were determined by morphological and biochemical characterisation, followed by a sequence analysis of the ribosomal RNA gene (16S rRNA for AAB and ITS for yeast). The changes in the microbial composition were associated with variations in the physico-chemical characteristics of kombucha tea, such as pH, titratable acidity, and total soluble solids (TSS). During fermentation, the acidity increased and the TSS decreased. The yield, moisture content, and water activity of the cellulosic pellicles which had developed at the end of fermentation were attributed to the presence of AAB. The dominant AAB species in the cellulosic pellicles and kombucha broth were identified as Komagataeibacter rhaeticus. The yeast isolates belonged to Debaryomyces prosopidis and Zygosaccharomyces lentus.

13.
Bioresour Technol ; 385: 129309, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37311530

RESUMEN

A novel heterotrophic nitrification and aerobic denitrification (HN-AD) bacterium D1-1 was identified as Pseudomonas nicosulfuronedens D1-1. Strain D1-1 removed 97.24%, 97.25%, and 77.12% of 100 mg/L NH4+-N, NO3--N, and NO2--N, with corresponding maximum removal rates of 7.42, 8.69, and 7.15 mg·L-1·h-1, respectively. Strain D1-1 bioaugmentation enhanced woodchip bioreactor performance with an average NO3--N removal efficiency of 93.8%. Bioaugmentation enriched N cyclers along with increased bacterial diversity and predicted genes for denitrification, DNRA (dissimilatory nitrate reduction to ammonium), and ammonium oxidation. It also reduced local selection and network modularity from 4.336 to 0.934, resulting in predicted nitrogen (N) cycling genes shared by more modules. These observations suggested that bioaugmentation could enhance the functional redundancy to stabilize the NO3--N removal performance. This study provides insights into the potential applications of HN-AD bacteria in bioremediation or other environmental engineering fields, relying on their ability to shape bacterial communities.


Asunto(s)
Compuestos de Amonio , Pseudomonas , Desnitrificación , Aerobiosis , Nitrificación , Reactores Biológicos , Nitrógeno , Procesos Heterotróficos , Nitritos
14.
Ying Yong Sheng Tai Xue Bao ; 34(3): 761-769, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37087660

RESUMEN

The Yellow River Basin is short of water resources. The dynamic monitoring of surface water area is helpful to clarify the distribution and change trend of water resources in this area. It is of great scientific significance to deeply understand the impacts of climate change and human activities on water resources and ensure the ecological security of the basin. Based on the Google Earth Engine (GEE) cloud platform, we analyzed the spatial variations of surface water area in the Yellow River Basin from 1986 to 2021 by using the mixed index algorithm, and revealed the driving factors of surface water area change in the Yellow River Basin. The results showed that the overall recognition accuracy of the water extraction algorithm based on mixing index was 97.5%. Compared with available water data products, the proposed algorithm can guarantee the integrity of the whole water area to a certain extent. The surface water area in the upper, middle, and lower reaches of the Yellow River Basin was 71.7%, 18.4%, and 9.9% of the total surface water area, respectively. From 1986 to 2021, the surface water area of the basin showed an overall upward trend, with a total increase of 3163.6 km2. The surface water area of the upper, middle, and downstream regions increased by 72.0%, 22.4%, and 5.6%, respectively. The increase of precipitation was the main reason for the increase of water area, with a contribution of 55%. Vegetation restoration and construction of water conservancy projects had increased the water area of the basin. The intensification of human water extraction activity reduced the water area of the basin.


Asunto(s)
Monitoreo del Ambiente , Agua , Humanos , Ríos , Cambio Climático , Algoritmos , China
15.
Anal Chim Acta ; 1252: 341074, 2023 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-36935132

RESUMEN

G4 DNA structure highly localized to functionally important sites within the human genome, has been identified as a biomarker for regulation of multiple biological processes. Identification G4-responsive fluorescence probes has broad application prospects for addressing G4 biological functions, as well as developing of new families of anticancer drugs. However, some currently designed G4 DNA probes may suffer from serious solvent-dependent effect, and cause unspecific fluorescence that masks the specific signal from G4 DNA. Herein, with a bulky imidazole-cored molecular rotor fusing in D-A building block of carbazole-pyridinium, we constructed a new probe ACPS. This new probe with desirable environmentally insensitive property exhibited a "fluorescence-off" state in various polarity solvents. In the presence of G4 DNA, the intra-molecular rotations would be restricted, triggering intense fluorescence enhancement. Especially, probe ACPS bound to G4 DNA structures with superior selectivity, exhibiting much weaker fluorescence response in the presence of non-G4 DNA structures. This probe was also able to realize fluorescence visualization in cell imaging. Collectively, the probe design strategy eliminates the background fluorescence caused by uncontrollable environmental polarity change, thereby achieving high-fidelity sensing G4 DNA structures in complicated systems.


Asunto(s)
Colorantes Fluorescentes , G-Cuádruplex , Humanos , Colorantes Fluorescentes/química , Fluorescencia , ADN/química
16.
Proc Natl Acad Sci U S A ; 120(3): e2207832120, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36626561

RESUMEN

Microorganisms play essential roles in soil ecosystem functioning and maintenance, but methods are currently lacking for quantitative assessments of the mechanisms underlying microbial diversity patterns observed across disparate systems and scales. Here we established a quantitative model to incorporate pH into metabolic theory to capture and explain some of the unexplained variation in the relationship between temperature and soil bacterial diversity. We then tested and validated our newly developed models across multiple scales of ecological organization. At the species level, we modeled the diversification rate of the model bacterium Pseudomonas fluorescens evolving under laboratory media gradients varying in temperature and pH. At the community level, we modeled patterns of bacterial communities in paddy soils across a continental scale, which included natural gradients of pH and temperature. Last, we further extended our model at a global scale by integrating a meta-analysis comprising 870 soils collected worldwide from a wide range of ecosystems. Our results were robust in consistently predicting the distributional patterns of bacterial diversity across soil temperature and pH gradients-with model variation explaining from 7 to 66% of the variation in bacterial diversity, depending on the scale and system complexity. Together, our study represents a nexus point for the integration of soil bacterial diversity and quantitative models with the potential to be used at distinct spatiotemporal scales. By mechanistically representing pH into metabolic theory, our study enhances our capacity to explain and predict the patterns of bacterial diversity and functioning under current or future climate change scenarios.


Asunto(s)
Ecosistema , Suelo , Suelo/química , Microbiología del Suelo , Bacterias/genética , Bacterias/metabolismo , Concentración de Iones de Hidrógeno , Biodiversidad
17.
J Environ Manage ; 325(Pt A): 116499, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36257227

RESUMEN

Over-compensatory growth of plants after disturbance is generally preferred by grassland users and managers because of more forage. How the grassland productivity and the plant growth condition before disturbance affect the compensatory growth are important for grazing management and the understanding of grassland degradation, yet they are not well understood. A clipping experiment was conducted on the Qinghai-Tibetan Plateau to understand the compensatory growth and conditions for the occurrence of over-compensatory at alpine meadows with different degradation status. Results showed the competition for light constrains the plant growth post-clipping at non-degraded and slightly degraded alpine meadows, while the reduction of soil nitrogen limits it at heavily degraded alpine meadow. The biomass accumulated post-clipping was positively correlated with the growing season biomass in unclipped plots and the biomass at clipping in clipped plots. When the aboveground biomass at clipping was less than 40.10 g m-2 and the growing season biomass was between 38 and 97 g m-2, the over-compensatory growth of alpine meadow could occur. Higher clipping rate is required for the alpine meadow with high productivity but the maximum clipping rate should be less than 0.71 to induce the over-compensatory growth. Equal-compensatory occurred at non-degraded and slightly degraded, while over-compensatory growth was observed at moderately degraded and a marginally significant over-compensatory growth at heavily degraded alpine meadow. The over-compensatory growth occurred at moderately degraded alpine meadow is mainly due to the performance of forbs. Our results suggest that grazing at moderately degraded alpine meadow may induce the over-compensatory growth at the community level, but the over-compensatory growth of forbs at moderately degraded alpine meadow may aggravate the alpine meadow degradation.


Asunto(s)
Pradera , Suelo , Tibet , Biomasa , Nitrógeno/análisis , Plantas/metabolismo
18.
Cell Death Dis ; 13(12): 1031, 2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36494334

RESUMEN

The cell-cell interaction between hepatocytes and Kupffer cells (KCs) is crucial for maintaining liver homeostasis, and the loss of KCs and hepatocytes is known to represent a common pathogenic phenomenon in autoimmune hepatitis. Until now, the mechanisms of cell-cell interaction between hepatocytes and KCs involved in immune-mediated hepatitis remains unclear. Here we dissected the impact of activated mTORC1 on the cell-cell interaction of KCs and hepatocyte in immune-mediated hepatitis. In the liver from patients with AIH and mice administrated with Con-A, mTORC1 was activated in both KCs and hepatocytes. The activated mTORC1 signal in hepatocytes with Con-A challenge caused a markedly production of miR-329-3p. Upregulated miR-329-3p inhibited SGMS1 expression in KCs through paracrine, resulting in the death of KCs. Most of maintained KCs were p-S6 positive and distributed in hepatocyte mTORC1 negative area. The activation of mTORC1 enabled KCs expressed complement factor B (CFB) to enhance the complement alternative system, which produced more complement factors to aggravate liver injury. Our findings remonstrate a heterogeneous role of mTORC1 in specific cell type for maintaining tolerogenic liver environment, and will form the basis for the development of new interventions against immune-mediated hepatitis.


Asunto(s)
Hepatitis , MicroARNs , Ratones , Animales , Macrófagos del Hígado/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Hepatocitos/metabolismo , Hepatitis/metabolismo , Hígado , Concanavalina A , MicroARNs/metabolismo
20.
Huan Jing Ke Xue ; 43(11): 5084-5095, 2022 Nov 08.
Artículo en Chino | MEDLINE | ID: mdl-36437080

RESUMEN

Mining activities change the groundwater level and flow conditions through pumping and drainage, which enhances the interaction between groundwater and aquifer rocks; mine drainage is discharged into the surface water system, which affects the whole karst water hydrogeochemical process. Based on hydrogeochemistry and the δ34S isotope, the hydrogeochemical processes, characteristics, and main controlling factors for waste water, karst groundwater, and surface water in a typical Carlin gold mining area and its surrounding areas were revealed. The results showed that:chemical compositions of groundwater and surface water unaffected by gold mining activities were mainly controlled by the weathering of limestone and dolomitic limestone; Ca2+, Mg2+, and HCO3- were main ions; and the water chemical types were Ca-HCO3. The mine wastewater and its downstream receiving water were affected by the dissolution of carbonate and silicate minerals, and cation exchange also played a role; the main ions were Ca2+, Mg2+, Na+, and SO42-, and the hydrochemical type gradually evolved from Ca-HCO3 to Ca-SO4. SO42- was the characteristic component in various water bodies affected by mining, and the concentration of SO42- gradually decreased from top to bottom in the well. The values of δ34S for unaffected groundwater and surface water were positive, and SO42- was mainly derived from realgar oxidation. Conversely, mine wastewater and downstream water were negative, SO42- was mainly influenced by the mixing action of realgar oxidation and meteoric precipitation, and pyrite also contributed to a certain extent. At the same time, NO3- came from agricultural fertilizer and rural domestic sewage discharge directly. Principal component analysis (PCA) further demonstrated:sulfide mineral oxidation and mining activities were the main controlling factors for the water chemical composition of mine wastewater and downstream water, whereas unaffected groundwater and surface water were mainly influenced by water-rock (carbonate rock) interactions. Agricultural fertilizer and rural sewage discharge also had a certain influence. Therefore, the study area should strengthen the interception of surface water, control-block-management of sulfide oxidation, rural domestic sewage treatment, and agricultural fertilizer.


Asunto(s)
Oro , Aguas Residuales , Aguas del Alcantarillado , Fertilizantes , Isótopos de Azufre , Carbonato de Calcio , Minería , Sulfuros
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