Effect of selenium supplements on the antioxidant activity and nitrite degradation of lactic acid bacteria.

Selenium (Se) is one of the essential trace elements in the human body, and Se-enriched lactic acid bacteria (LAB) can improve the biological utilization value of inorganic Se. The aim of this study was to isolate Se-enriched LAB and study their effects on antioxidant activity and nitrite degradation. The Se-enriched LAB L.P2, which was nitrite-tolerant and could grow in 30 µg/mL sodium selenite (Na2SeO3) medium, was isolated from the traditional fermented Chinese sauerkraut. L.P2 belonged to Lactobacillus plantarum according to the 16S rDNA analysis. The biomass and lactic acid production of L.P2 reached to a maximum (9.52 log CFU/mL and 16.99 mg/mL) when 2.0 µg/mL Na2SeO3 was supplemented in the medium. Additionally, the nitrite degradation rate reached 85.76% when the initial concentration of Na2SeO3 was 2.0 µg/mL. The Se-enriched LAB enhanced the scavenging capacity of hydroxyl radical and superoxide free radical of L.P2 and improved the lipid peroxidation and ion-chelating abilities. Moreover, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in Se 4 group (4.0 µg/mL Na2SeO3 was added) reached 48.49 and 50.35 U/mg, respectively. Thus, Se 4 concentration was significantly higher than that of Se 0 group (with no Se added). In particular, SOD and GSH-Px enzymes correlated with nitrite degradation (P < 0.01). Collectively, our results indicate that Se supplementation can enhance the antioxidant capacity of LAB, contribute to its nitrite degradation, and thus may have potential applications in functional foods.

Bridging gaps and seeding futures: A synthesis of soil salinization and the role of plant-soil interactions under climate change.

Soil salinization, exacerbated by climate change, poses significant threats to agricultural productivity, land restoration, and ecosystem resilience. This study reviews current knowledge on plant-soil interactions as a strategy to mitigate soil salinization induced by climate change, focusing on their role in soil salinity dynamics and tolerance mechanisms. The review examines how alterations in hydrological and temperature regimes impact soil salinity and how plant-soil mechanisms-such as salt exclusion, compartmentalization, and plant-microbe interactions-contribute to salinity mitigation. This, in turn, enhances soil quality, fertility, microbial diversity, and ecosystem services. The analysis identifies a growing body of research and highlights key themes and emerging trends, including drought, microbial communities, and salt tolerance strategies. This study underscores the critical role of plant-soil interactions in sustainable salinity management and identifies knowledge gaps and future research priorities, advocating for plant-soil interactions as a crucial pathway for improving ecosystem resilience to salinity stress amid climate change.

Structure control and evolution of atomically precise gold clusters as heterogeneous precatalysts.

Metal clusters have distinct features from single atom and nanoparticle (>1 nm) catalysts, making them effective catalysts for various heterogeneous reactions. Nevertheless, the ambiguity and complexity of the catalyst structure preclude in-depth mechanistic studies. The evolution of metal species during synthesis and reaction processes represents another challenge. One effective solution is to precisely control the structure of the metal cluster, thus offering a well-defined pre-catalyst. The well-defined chemical formula and configurations make atomically precise metal nanoclusters optimal choices. To fabricate an atomically precise metal nanocluster-based heterogeneous catalyst with enhanced performance, careful structural design of both the nanocluster and support material, an effective assembling technique, and a pre-treatment method for these hybrids need to be developed. In this review, we summarize recent advances in in the development of heterogeneous catalysts using atomically precise gold and alloy gold nanoclusters as precursors. We will begin with a brief introduction to the structural properties of atomically precise nanoclusters and structure determination of cluster/support hybrids. We will then introduce heterogeneous catalysts prepared from medium size (tens to hundreds of metal atoms) and low nuclearity nanoclusters. We will illustrate how ligand modification, support-cluster interaction, hybrid fabrication, and heteroatom (Pt, Pd Ag, Cu, Cd, Fe) introduction affect the structural properties and pretreatment/reaction-induced structural evolution of gold nanocluster pre-catalysts. Lastly, we will highlight the synthetic method of NCs@MOF hybrids and their effectiveness in circumventing the adverse cluster structural evolution. These findings are expected to shed light on the structure-activity relationship studies and future catalyst design strategies using atomically precise metal nanocluster pre-catalysts.

Dual-energy CT Radiomics Combined with Quantitative Parameters for Differentiating Lung Adenocarcinoma From Squamous Cell Carcinoma: A Dual-center Study.

RATIONALE AND OBJECTIVES: To evaluate the ability of dual-energy CT(DECT)-based quantitative parameters and radiomics features to differentiate solid lung adenocarcinoma (ADC) from squamous cell carcinoma (SCC). METHODS: This study included 213 patients diagnosed with ADC and SCC who underwent DECT scans at two centers from November 2022 to December 2023. Patients at center 1 were randomly divided into training (n = 114) and internal test set (n = 50) in a 7:3 ratio, with center 2 serving as the external test set (n = 49). Radiologic and clinical data were combined to establish a clinical-radiologic model. Ten types of DECT energy images including conventional images, iodine density (ID), effective atomic number (Zeff), electron density, and virtual mono-energetic images (VMI) were reconstructed in both arterial phases (AP) and venous phases (VP). Quantitative parameters were measured at the uniform enhanced solid portion of the tumor and normalized to the aorta, used to develop a quantification model and calculate the quantitative score (quantscore). Radiologists manually delineated the tumor ROI at the largest level for extracting radiomics features in these 10 energy images. These features were used to establish 10 uni-energy models from which the best-performing features were selected to construct the final radiomics model and calculate a radiomics score (radscore). Then, a combined model was developed using the akaike information criterion(AIC) and compared to the clinical-radiological model to test its diagnostic validity. RESULTS: The independent predictors of the clinical-radiological model included age, gender, and central or peripheral location, and the AUCs for the training set, internal test set, and external test set were 0.808, 0.837, and 0.802. The quantification model incorporated 40 keV CT values, Zeff, normalized Zeff, and the slope of the spectral attenuation curve (λHU) in the AP and normalized ID, Zeff, and λHU in the VP. Uni-energy models based on AP ID maps, AP Zeff maps, and VP VMI 65 keV significantly outperformed AUC= 0.5, and 11 radiomics features were selected from these three models to construct the final radiomics model. The combined model, incorporating age, gender, quantscore, and radscore, significantly outperformed the clinical-radiological model in the training set (AUC=0.952 vs 0.808, P < 0.001), and demonstrated higher performance in both the internal and external test sets, although these differences did not reach statistical significance (AUC=0.870 vs 0.837, for the internal test set [P = 0.542], 0.888 vs 0.802 for the external test sets [P = 0.128]). The evaluation of the combined model demonstrated good discriminative ability and potential for generalization. CONCLUSION: The combined model, integrating quantitative parameters and radiomics features from DECT multi-energy images with clinical-radiological characteristics, can be used as a non-invasive tool to differentiate ADC from SCC.

Efficacy and safety of immune checkpoint inhibitors with or without radiotherapy in metastatic non-small cell lung cancer: A systematic review and meta-analysis.

Background and purpose: Although immune checkpoint inhibitors (ICIs) have become the first-line treatment for metastatic non-small cell lung cancer (mNSCLC), their efficacy is limited. Meanwhile, recent reports suggest that radiotherapy (RT) can activate the systemic antitumor immune response by increasing the release of antigens from tumor tissues. Therefore, in patients with mNSCLC treated with ICIs, investigations were performed to determine whether the addition of RT improved the outcomes. Furthermore, the adverse events rate was evaluated. Methods and materials: Pubmed, Embase, and Cochrane Library were searched using the keywords "radiotherapy," "immune checkpoint inhibitors," and "non-small cell lung cancer" from the date of inception to 2 May 2022. Randomized controlled trials (RCTs) and nonRCTs (NRCTs) comparing the efficacy and safety of RT combined with ICIs versus ICIs alone in metastatic NSCLC were assessed. The primary outcomes were progression-free survival (PFS) and overall survival (OS), and the secondary outcomes were abscopal response rate (ARR), abscopal control rate (ACR), adverse events rate, and pneumonia rate. The analyses were conducted using the Mantel-Haenszel fixed-effects or random-effects model. The I2 statistic was used to determine heterogeneity, whereas funnel plots and Egger's test were used to assess publication bias. Results: In 15 clinical studies, 713 patients received RT combined with ICIs and 1,275 patients received only ICIs. With regard to PFS and OS, the hazard ratios of RT combined with ICIs were 0.79 (0.70, 0.89) and 0.72 (0.63, 0.82), respectively. In terms of ARR and ACR, the odds ratios (ORs) of RT combined with ICIs were 1.94 (1.19, 3.17) and 1.79 (1.08, 2.97), respectively. Subgroup analyses based on study type (RCT/NRCT), RT target (intracranial/extracranial), number of RT sites (single site), previous ICI resistance (yes/no), and sequencing of RT and ICIs (concurrent/post-RT ICIs) revealed that the addition of RT significantly prolonged PFS and OS. However, subgroup analyses based on radiation dose/fractionation indicated that the addition of hypofractionated RT significantly prolonged OS but not PFS. When grouped according to the level of PD-L1 expression, the addition of RT prolonged PFS only in patients who were PD-L1-negative. Furthermore, subgroup analyses of ARR and ACR signified that the combination therapy resulted in better local control of lesions outside the irradiation field in the hypofractionated RT, extracranial RT, and ICI-naïve subgroups. In terms of adverse events, the addition of RT did not significantly increase the adverse events rate but was associated with a higher pneumonia rate [OR values were 1.24 (0.92, 1.67) and 1.76 (1.12, 2.77), respectively]. Conclusion: Meta-analysis of existing data suggests that the addition of RT can significantly prolong PFS and OS in patients with metastatic NSCLC receiving ICIs. In addition to lesions in the irradiation field, RT can improve the local control rate of lesions outside the irradiation field via immune activation. Combination therapy does not increase the overall risk of adverse reactions, except for pneumonia.

Reveal the threat of water quality risks in Yellow River Delta based on evidences from isotopic and hydrochemical analyses.

This study aims to evaluate the seasonal and spatial characteristics of hydrochemistry and DO isotopes and identify the eco-environmental threats under the background of saline intrusion and human activities in Yellow River Delta (YRD). Analyses for major ions (i.e., K+, Na+, Ca2+, Mg2+, SO42-, HCO3- and Cl-), nitrate ion (NO3-) and isotopic composition are performed for precipitation, river water, wetland water and sea water. Based on the range of δ2H and δ18O as well as their relations, the mixing between multiple sources and evaporation are confirmed. Electrical conductivity (EC), concentration of NO3-, soluble sodium percentage (SSP) and magnesium hazard (MH) are employed as indicators to reflect the ecological risks from salinity, agricultural pollutants, sodium and magnesium. By hierarchical cluster analysis (HCA), the samples of wetland water are grouped associated with those of river water. The characteristic reflects 3 patterns of risks in wetlands, including saline intrusion, human activities and their mixed influence.

Distribution of hydrogen and oxygen stable isotopes and pollution indicators in water during a monsoon transitional period in Min River Basin.

Based on 197 monthly river water and groundwater samples and 30 event-scale precipitation samples, our study reports the distribution of hydrogen and oxygen isotopes and pollution indicators in Min River Basin. The variation of δ18O and d-excess indicate that the water source in the upper main course water is more variable and that in the middle-lower part is relatively stable. Comparison between plots of δ2H versus δ18O in the river water and precipitation reflect the dominant water source is different between river water in the upper and middle-lower parts. The electrical conductivity (EC) shows a similar spatial variation trend for main course water collected in four campaigns. The pollutant concentration change at the confluences of main tributaries shows that the inflow of Heishui River and Dadu River leads to decreased NO3- and Cl-, while that of Xi River, Pu River and Fuhe River leads to a leap in NO3- and Cl-. A significant positive correlation is observed between EC and δ18O, indicating the consistent control of water sources on isotope distribution and water quality. The relationship between elevation and δ18O in the main course river water suggests that the factors affecting isotope distribution vary spatially. "Altitude effect" can only be observed in October and November for the upper steepest plateau zone due to the spatial variation in the precipitation stored during the wet season. The "inverse altitude effect" is observed for the upper part during the wet season and for the middle-lower part during the whole study period, which can be explained by the contribution of tributaries with different discharge regimes. Our findings show that water source with different discharge regimes can serve as the leading factor controlling the stream component in multi-tributary river basins with large spatial span and may mask the influence of spatial distribution of precipitation.

Using stable isotopes as tracer to investigate hydrological condition and estimate water residence time in a plain region, Chengdu, China.

The oxygen and hydrogen isotopic compositions (δ18O and δ2H) were measured on river water and precipitation collected from four sub-catchments within the upper Tuojiang River catchment. δ18O values of river water and precipitation exhibit significant seasonal variations. These seasonal variations are used for estimating the mean residence time (MRT) for four sub-catchments by an exponential model, ranging from 346 to 493 days. The correlation between catchment MRT and mean slope of the catchment (r2 = 0.29) is weak, while the correlations between catchment MRT, catchment area (r2 = 0.79) and topographic index (r2 = 0.98) are strong. These results indicate that topography and catchment area, both control the catchment MRT and the topographic index may be a reliable parameter for estimating the catchment MRT. Moreover, the relationship between land use types and MRT was investigated. The results show that paddy fields (r2 = 0.95) compared to the other land use types may have a greater impact on the MRT of the irrigation-dominated catchment. This study provides a preliminary exploration of the factors affecting MRT in the plain region and a basis for simulating MRT in the future.

Revealing the impact of water conservancy projects and urbanization on hydrological cycle based on the distribution of hydrogen and oxygen isotopes in water.

In recent years, the development and utilization of water resources have imposed great impacts on hydrological characteristics and ecological environment. In this paper, methods based on stable isotopes were used to analyze the cumulative effect of water projects and urbanization on the hydrological cycle in Qingbaijiang River Basin. Isotope evidence shows that the hydrological processes affected by water regulation and urbanized runoff generation differentiate greatly from the natural state. The annual mean isotopic values follow an order of groundwater > rainwater > river water. Consistent isotopic composition and variation trend between the near-bank groundwater and river water were only observed from May to late June 2018 and from February to April 2019 in the upper zone, indicating the dominant recharge of river to the groundwater. However, the isotopic variations between the two waters in the middle and lower zones suggested that the hydraulic exchange was limited, demonstrating the significant changes in river water level caused by the reservoir impoundment. The isotopic enrichment rate along the flow path is highest in January (0.0265‰/km), followed by October (0.0160‰/km), indicating the significant evaporation, while slight spatial changes in July (0.0027‰/km) reflected masked evaporation effect. This variability can be mainly attributed to the flow rate change and increase of water salinity in anthropic zones. Periodic regression analysis was employed to evaluate the difference in rainfall-runoff responses between hydrographic zones and estimate the mean residence time (MRT). Periodicity of isotopes in river water increased from upper to lower reaches with increasing R2 values from 0.04 in SW1 to 0.46 in SW8. The MRT grew shorter along the flow path from 870 days in SW1 to 293 days in SW8, reflecting accelerated rainfall-runoff process due to the increasing impervious surface area and drainage system. These results identify the sensitivity of stable isotopes to the land use changes, runoff generation, and topography, and have implication for the potential water and environmental risks. Based on these understandings, suggestions for sustainable water-environment management in urban and rural areas were proposed.

Prevention and treatment of radiation-induced lung injury.

Radiation-induced lung injury (RILI) is a common complication in cancer patients receiving local thoracic radiation and bone marrow transplantation conditioning. It is divided into early-stage radiation pneumonitis and advanced radiation fibrosis of the lung. This severely hampers the quality of life and survival of cancer patients. Meanwhile, RILI is a major factor limiting radiation doses in clinical practice, which affects the local control of cancer. Unfortunately, the mechanism of RILI is still not well defined, and there are no treatment options available for these patients. In this review we summarize the methods and agents used for the treatment and prevention of RILI, with the aim of increasing understanding of RILI.