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1.
J Hazard Mater ; 479: 135698, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-39217934

RESUMEN

The source diversity and health risk of trace elements (TEs) in soil make it necessary to reveal the relationship between pollution, source, and risk. However, neglect of spatial heterogeneity restricts the reliability of existing identification methods. In this study, spatial heterogeneity is proposed as a necessary and feasible factor for accurately dissecting the pollution-source-risk link of soil TEs. A comprehensive framework is developed by integrating positive matrix factorization, Geodetector, and risk evaluation tools, and successfully applied in a mining-intensive city in northern China. Overall, the TEs are derived from natural background (28.5 %), atmospheric deposition (25.6 %), coal mining (21.8 %), and metal industry (24.1 %). The formation mechanism of heterogeneity for high-variance TEs (Se, Hg, Cd) is first systematically deciphered by revealing the heterogeneous source-sink relationship. Specifically, Se is dominated (76.5 %) by heterogeneous coal mining (q=0.187), Hg is determined (92.6 %) by the heterogeneity of metal mining (q=0.183) and smelting (q=0.363), and Cd is caused (50.9 %) by heterogeneous atmospheric deposition (q>0.254) co-influenced by the terrains and soil properties. Highly heterogeneous sources are also noteworthy for their potential to pose extreme risks (THI=1.122) in local areas. This study highlights the necessity of integrating spatial heterogeneity in pollution and risk assessment of soil TEs.

2.
Water Res ; 267: 122473, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39306935

RESUMEN

The discharge of wastewater into rivers can lead to resistome coalescence, thereby enhancing the spread risk of antibiotic resistance genes (ARGs) through mixing of exogenous wastewater resistome communities with indigenous riverine communities. At present, the understanding on the role of resistome community coalescence in the dissemination of ARGs is still very limited, and little is known about the process and its ecological implications. To bridge the gap, this study has conducted field-based surveys and microcosm experiments to deeply dissect the coalescence of resistome community in wastewater within river environment, utilizing genome-centric metagenomic analysis approach. The field investigation suggests resistome coalescence enhances the abundance and diversity of ARGs in the receiving river. Furthermore, the microcosm experiments reveal the effect of mixing ratio on resistome coalescence in the water-sediment system and decipher the temporal attenuation dynamics of the coalesced resistome in the environment. The results show the higher proportion of wastewater has a greater impact on ARGs in the water, whereas the effect of mixing ratio is lesser in the sediments. Temporally, the source-specific ARGs originating from wastewater exhibit decreasing trends over the experimental duration, and relatively, the attenuation in the water is more pronounced than that in the sediments. Interestingly, natural light not only facilitates the attenuation of ARGs in the water but may also induce their deposition at the water-sediment interface. Variance partitioning analyses suggest the microbiome, mobilome, and abiotic factors collectively shape the coalescence of the resistome communities in the environment. The study provides empirical evidence on resistome coalescence in river systems, which is instrumental in gaining a better understanding of the spread mechanism of ARGs in the environment.

3.
Chemosphere ; 364: 143299, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39251159

RESUMEN

Heavy metals (HMs) in soils pose significant risks on ecosystem and human health. To design targeted regulatory measures for mitigating and controlling the risk, it is necessary to accurately identify the pollution sources and environmental risks of soil HMs, as well as to reveal the linkages between them. To date, yet systematic investigation aimed at deciphering the links between source apportionment of soil HMs and their associated environmental risks is still lacking. To fill the gap, an integrated framework has been developed in this study and applied for dissecting the source-sink relationship and source-oriented ecological and health risks of soil HMs in Shanxi, a province with rich coal resource, in which long-term coal mining activities in history has resulted in soil HMs pollution and unavoidably posed environmental risks. Two advanced receptor models, multivariate curve resolution alternating least squares based on maximum likelihood principal component analysis (MCR-ALS/MLPCA) and multilinear engine 2 (ME2), have been employed for apportioning the potential sources, and their apportionment results are jointly incorporated into a modified ecological risk index and a probabilistic health risk assessment model for identifying the source-oriented ecological and health risks posed by soil metals. The results show that the soils in study area have been polluted by HMs (i.e., Cd, Cr, Hg and As) to varying degrees. Industrial activities (35%-35.8%), agricultural activities (11.1%-20.5%), atmospheric deposition (10.5%-13%) and mix source (31.5%-42.6%) are apportioned as the main contributors of soil HMs in the area. The source-oriented ecological risk assessment suggests Hg has presented significant ecological risk and largely contributed by the sources from atmospheric deposition and industrial activities. The source-oriented health risk assessment shows the non-carcinogenic hazard level and carcinogenic risk posed by soil HMs in the study area are acceptable. Relatively, industrial activities and mix source have contributed more on the health risks.

4.
Magn Reson Med ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39285623

RESUMEN

PURPOSE: To develop a model-based motion correction (MoCo) method that does not need an analytical signal model to improve the quality of cardiac multi-parametric mapping. METHODS: The proposed method constructs a hybrid loss that includes a dictionary-matching loss and a signal low-rankness loss, where the former registers the multi-contrast original images to a set of motion-free synthetic images and the latter forces the deformed images to be spatiotemporally coherent. We compared the proposed method with non-MoCo, a pairwise registration method (Pairwise-MI), and a groupwise registration method (pTVreg) via a free-breathing Multimapping dataset of 15 healthy subjects, both quantitatively and qualitatively. RESULTS: The proposed method achieved the lowest contour tracking errors (epicardium: 2.00 ± 0.39 mm vs 4.93 ± 2.29 mm, 3.50 ± 1.26 mm, and 2.61 ± 1.00 mm, and endocardium: 1.84 ± 0.34 mm vs 4.93 ± 2.40 mm, 3.43 ± 1.27 mm, and 2.55 ± 1.09 mm for the proposed method, non-MoCo, Pairwise-MI, and pTVreg, respectively; all p < 0.01) and the lowest dictionary matching errors among all methods. The proposed method also achieved the highest scores on the visual quality of mapping (T1: 4.74 ± 0.33 vs 2.91 ± 0.82, 3.58 ± 0.87, and 3.97 ± 1.05, and T2: 4.48 ± 0.56 vs 2.59 ± 0.81, 3.56 ± 0.93, and 4.14 ± 0.80 for the proposed method, non-MoCo, Pairwise-MI, and pTVreg, respectively; all p < 0.01). Finally, the proposed method had similar T1 and T2 mean values and SDs relative to the breath-hold reference in nearly all myocardial segments, whereas all other methods led to significantly different T1 and T2 measures and increases of SDs in multiple segments. CONCLUSION: The proposed method significantly improves the motion correction accuracy and mapping quality compared with non-MoCo and alternative image-based methods.

5.
Cell Mol Life Sci ; 81(1): 397, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261351

RESUMEN

Inflammatory bowel diseases (IBDs) are immune chronic diseases characterized by recurrent episodes, resulting in continuous intestinal barrier damage and intestinal microbiota dysbiosis. Safe strategies aimed at stabilizing and reducing IBDs recurrence have been vigorously pursued. Here, we constructed a recurrent intestinal injury Drosophila model and found that vitamin B12 (VB12), an essential co-factor for organism physiological functions, could effectively protect the intestine and reduce dextran sulfate sodium-induced intestinal barrier disruption. VB12 also alleviated microbial dysbiosis in the Drosophila model and inhibited the growth of gram-negative bacteria. We demonstrated that VB12 could mitigate intestinal damage by activating the hypoxia-inducible factor-1 signaling pathway in injured conditions, which was achieved by regulating the intestinal oxidation. In addition, we also validated the protective effect of VB12 in a murine acute colitis model. In summary, we offer new insights and implications for the potential supportive role of VB12 in the management of recurrent IBDs flare-ups.


Asunto(s)
Sulfato de Dextran , Modelos Animales de Enfermedad , Microbioma Gastrointestinal , Factor 1 Inducible por Hipoxia , Mucosa Intestinal , Transducción de Señal , Vitamina B 12 , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Vitamina B 12/farmacología , Vitamina B 12/metabolismo , Ratones , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Transducción de Señal/efectos de los fármacos , Sulfato de Dextran/toxicidad , Factor 1 Inducible por Hipoxia/metabolismo , Colitis/metabolismo , Colitis/inducido químicamente , Colitis/microbiología , Colitis/patología , Colitis/tratamiento farmacológico , Disbiosis/microbiología , Disbiosis/metabolismo , Ratones Endogámicos C57BL , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/microbiología , Enfermedades Inflamatorias del Intestino/patología , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Drosophila/metabolismo
6.
J Thorac Oncol ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39260521

RESUMEN

INTRODUCTION: Leptomeningeal metastasis (LM) is one of the most severe complications of non-small cell lung cancer (NSCLC). Furmonertinib is a pan-epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) with a high rate of brain penetration and a wide therapeutic window. Here, we evaluated the efficacy and safety of high-dose furmonertinib in patients with EGFR-mutated NSCLC and LM. METHODS: This prospective real-world study included patients with EGFR-mutated NSCLC and LM treated with a high-dose furmonertinib (240 mg once daily) as a monotherapy or in combination with other treatments. The primary endpoint was overall survival (OS), and the secondary endpoints included time to treatment discontinuation (TTD) and clinical response rate. Additional efficacy evaluations included changes in brain magnetic resonance imaging (MRI) by the RANO-LM radiologic criteria. We also introduced next generation sequencing (NGS)-based assays to evaluate genomic and epigenomic features of cell-free DNA (cfDNA) in patients' cerebrospinal fluid (CSF) samples and to analyze their associations with patient outcomes. RESULTS: We enrolled 48 patients, of whom 35 (72.9%) had received third-generation EGFR-TKIs. The median OS was 8.43 months (95%CI, 5.48 to 11.39 months), while the median TTD was 8.27 months (95%CI, 5.40 to 11.14 months), and the clinical response rate was 75%. The LM objective response rate (ORR) and disease control rate (DCR) assessed with RANO-LM radiologic criteria were 50.0% and 92.1%, respectively. The adverse event profiles were consistent with previous reports of furmonertinib. Briefly, 22 (45.8%) had adverse events (AEs) possibly related to furmonertinib and three (6.3%) had a grade 3-elevated aminotransaminase or nausea or leucopenia, leading to dose reduction to 160 mg daily. Furthermore, methylation analysis of cfDNA in CSF showed that there was a significant correlation between the changes of aberrant methylated fragments (AMFs) from lung cancer cells and the response of the patients. Meanwhile, the copy number burden (CNB) scores derived from the low-pass whole genome sequencing (LP-WGS) assay may offer another objective and effective method for the diagnosis and evaluation of treatment efficacy in LM. CONCLUSION: In the real world, the high-dose furmonertinib-based treatment may potentially have clinical efficacy and tolerable safety in patients of EGFR-mutated NSCLC with LM, even in patients previously treated with other third-generation EGFR-TKIs. Methylation and CNB analysis of cfDNA in CSF may be considered objective indicators for the diagnosis of LM and evaluation of treatment response.

7.
Bioresour Technol ; 412: 131371, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39209226

RESUMEN

This study is the first to explore the performance and mechanism of biochar-impacted sediment microbial fuel cell for removing antibiotic resistance genes (ARGs), and examines the effects of different biochar contents. The addition of 5% biochar produced the highest output voltage and power density, which increased by 100% and 219%, respectively, while simultaneously reducing the abundance and risk of ARGs. Comparatively, the addition of moderate amount of biochar (1-5%) promoted the removal of ARGs, while the opposite was true for excessive (10%) biochar. Biochar affected ARGs through prophages, insertion sequence, and transposons. Biological factors and voltage jointly influenced ARGs variation, with the former accounting for 56%. Further analysis of functional genes indicated that biochar controlled ARGs by regulating the synthesis of genetic material and amino acids to influence metabolism. Overall, findings of this study shed light on the potential removal of ARGs in microbial electrochemical systems.


Asunto(s)
Fuentes de Energía Bioeléctrica , Carbón Orgánico , Carbón Orgánico/química , Carbón Orgánico/farmacología , Farmacorresistencia Microbiana/genética , Sedimentos Geológicos/microbiología , Sedimentos Geológicos/química
8.
J Magn Reson Imaging ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143028

RESUMEN

BACKGROUND: Cardiac T1 mapping is valuable for evaluating myocardial fibrosis, yet its resolution and acquisition efficiency are limited, potentially obscuring visualization of small pathologies. PURPOSE: To develop a technique for high-resolution cardiac T1 mapping with a less-than-100-millisecond acquisition window based on radial MOdified Look-Locker Inversion recovery (MOLLI) and a calibrationless space-contrast-coil locally low-rank tensor (SCC-LLRT) constrained reconstruction. STUDY TYPE: Prospective. SUBJECTS/PHANTOM: Sixteen healthy subjects (age 25 ± 3 years, 44% females) and 12 patients with suspected cardiomyopathy (age 57 ± 15 years, 42% females), NiCl2-agar phantom. FIELD STRENGTH/SEQUENCE: 3-T, standard MOLLI, radial MOLLI, inversion-recovery spin-echo, late gadolinium enhancement. ASSESSMENT: SCC-LLRT was compared to a conventional locally low-rank (LLR) method through simulations using Normalized Root-Mean-Square Error (NRMSE) and Structural Similarity Index Measure (SSIM). Radial MOLLI was compared to standard MOLLI across phantom, healthy subjects, and patients. Three independent readers subjectively evaluated the quality of T1 maps using a 5-point scale (5 = best). STATISTICAL TESTS: Paired t-test, Wilcoxon signed-rank test, intraclass correlation coefficient analysis, linear regression, Bland-Altman analysis. P < 0.05 was considered statistically significant. RESULTS: In simulations, SCC-LLRT demonstrated a significant improvement in NRMSE and SSIM compared to LLR. In phantom, both radial MOLLI and standard MOLLI provided consistent T1 estimates across different heart rates. In healthy subjects, radial MOLLI exhibited a significantly lower mean T1 (1115 ± 39 msec vs. 1155 ± 36 msec), similar T1 SD (74 ± 14 msec vs. 67 ± 23 msec, P = 0.20), and similar T1 reproducibility (28 ± 18 msec vs. 22 ± 15 msec, P = 0.34) compared to standard MOLLI. In patients, the proposed method significantly improved the sharpness of myocardial boundaries (4.50 ± 0.65 vs. 3.25 ± 0.43), the conspicuity of papillary muscles and fine structures (4.33 ± 0.74 vs. 3.33 ± 0.47), and artifacts (4.75 ± 0.43 vs. 3.83 ± 0.55). The reconstruction time for a single slice was 5.2 hours. DATA CONCLUSION: The proposed method enables high-resolution cardiac T1 mapping with a short acquisition window and improved image quality. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 1.

9.
Materials (Basel) ; 17(15)2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39124301

RESUMEN

Thermoelectric materials that can convert thermal energy to electrical energy are stable and long-lasting and do not emit greenhouse gases; these properties render them useful in novel power generation devices that can conserve and utilize lost heat. SiC exhibits good mechanical properties, excellent corrosion resistance, high-temperature stability, non-toxicity, and environmental friendliness. It can withstand elevated temperatures and thermal shock and is well suited for thermoelectric conversions in high-temperature and harsh environments, such as supersonic vehicles and rockets. This paper reviews the potential of SiC as a high-temperature thermoelectric and third-generation wide-bandgap semiconductor material. Recent research on SiC thermoelectric materials is reviewed, and the principles and methods for optimizing the thermoelectric properties of SiC are discussed. Thus, this paper may contribute to increasing the application potential of SiC for thermoelectric energy conversion at high temperatures.

10.
Sci Total Environ ; 950: 175331, 2024 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-39117223

RESUMEN

Heavy metals in soils pose serious ecological and health risks. To make efficient strategies for mitigating the underlying hazards, it is critical to reveal the pollution sources and their links with the risks. Researchers have investigated source identification and risk evaluation of heavy metals in soils, yet few have systematically deciphered the source-sink relationship of soil metals and the links between source apportionment and risk assessment. In the study, an integrated technological framework has been proposed to address the gaps, and applied to characterize the pollution risks, sources and their links of soil metals in a typical coal resource city in China. The assessment using geochemical tool and ecological risk index shows the soils in study area are polluted by Cd, Hg, Cr, As and Pb in varied degrees, and particularly, Cd and Hg present significant ecological risk. Two advanced receptor models (multivariate curve resolution-weighted alternating least-squares and multilinear engine 2) are comparatively applied for apportioning the potential sources of soil metals, and the results suggest the two models have identified similar sources (r2 > 0.90), including agricultural activities, atmospheric depositions and industrial discharges with contributions of 35.5 %-38.3 %, 30.3 %-35.1 %, and 26.6 %-34.1 %, respectively. Then, apportionment results of the two models are jointly employed for evaluating the source-specific health risks of metals in the environment using a probabilistic risk assessment model. The risk levels within the area are overall acceptable or tolerable, and relatively, the industrial discharges present higher contribution on the non-carcinogenic and carcinogenic risks of soil metals to public. Findings will help the managers to design targeted policies for reducing the risks of soil metals, and the framework proposed provides a useful guideline to better understand the source-risk relationship of soil metals in other environments worldwide.

11.
Sci Rep ; 14(1): 18579, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39127852

RESUMEN

The effective detection of safflower in the field is crucial for implementing automated visual navigation and harvesting systems. Due to the small physical size of safflower clusters, their dense spatial distribution, and the complexity of field scenes, current target detection technologies face several challenges in safflower detection, such as insufficient accuracy and high computational demands. Therefore, this paper introduces an improved safflower target detection model based on YOLOv5, termed Safflower-YOLO (SF-YOLO). This model employs Ghost_conv to replace traditional convolution blocks in the backbone network, significantly enhancing computational efficiency. Furthermore, the CBAM attention mechanism is integrated into the backbone network, and a combined L C I O U + N W D loss function is introduced to allow for more precise feature extraction, enhanced adaptive fusion capabilities, and accelerated loss convergence. Anchor boxes, updated through K-means clustering, are used to replace the original anchors, enabling the model to better adapt to the multi-scale information of safflowers in the field. Data augmentation techniques such as Gaussian blur, noise addition, sharpening, and channel shuffling are applied to the dataset to maintain robustness against variations in lighting, noise, and visual angles. Experimental results demonstrate that SF-YOLO surpasses the original YOLOv5s model, with reductions in GFlops and Params from 15.8 to 13.2 G and 7.013 to 5.34 M, respectively, representing decreases of 16.6% and 23.9%. Concurrently, SF-YOLO's mAP0.5 increases by 1.3%, reaching 95.3%. This work enhances the accuracy of safflower detection in complex agricultural environments, providing a reference for subsequent autonomous visual navigation and automated non-destructive harvesting technologies in safflower operations.

12.
Aging Dis ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-39012662

RESUMEN

The increasing studies indicated that cardiovascular diseases, such as coronary artery disease (CAD), usually induce and exacerbate psychological problems, including anxiety and depression. These psychological issues are admitted as independent risk factors of heart disease as well. The interaction between CAD and anxiety and depression deteriorates the development and prognosis of CAD, which severely threatens the quality of life of patients. Although the existing mechanisms revealed the pathological relationship between CAD and anxiety and depression, there are few studies investigating the correlation between CAD and anxiety and depression from the aspect of gut microbiota (GM) and its metabolites. Therefore, in this review, we summarized whether GM and its metabolites are the emergent bridge between CAD and anxiety and depression. The results showed that there are four kinds of jointly up-regulated bacteria (i.e., Staphylococcus, Escherichia coli, Helicobacter pylori, and Shigella) and five kinds of jointly down-regulated bacteria (i.e., Prevotella, Lactobacillus, Faecalibacterium prausnitzii, Collinsella, and Bifidobacterium) in CAD as well as anxiety and depression. In addition, in CAD and anxiety and depression, the dysbiosis of the former four kinds of bacterium frequently leads to the outburst of inflammatory response, and the dysbiosis of the latter five kinds of bacterium is usually related to the metabolic abnormality of short-chain fatty acids, bile acids, and branched-chain amino acids. Therefore, we believe that GM and its metabolites act as the emergent bridge between CAD and anxiety and depression. The findings of this review provide novel insights and approaches for the clinical treatment of patients with both CAD and anxiety and depression.

13.
Dev Cell ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39047737

RESUMEN

Peroxisome dynamics are crucial for intestinal stem cell (ISC) differentiation and gut regeneration. However, the precise mechanisms that govern peroxisome dynamics within ISCs during gut regeneration remain unknown. Using mouse colitis and Drosophila intestine models, we have identified a negative-feedback control mechanism involving the transcription factors peroxisome proliferator-activated receptors (PPARs) and SOX21. This feedback mechanism effectively regulates peroxisome abundance during gut regeneration. Following gut injury, the released free very long-chain fatty acids (VLCFAs) increase peroxisome abundance by stimulating PPARs-PEX11s signaling. PPARs act to stimulate peroxisome fission and inhibit pexophagy. SOX21, which acts downstream of peroxisomes during ISC differentiation, induces peroxisome elimination through pexophagy while repressing PPAR expression. Hence, PPARs and SOX21 constitute a finely tuned negative-feedback loop that regulates peroxisome dynamics. These findings shed light on the complex molecular mechanisms underlying peroxisome regulation in ISCs, contributing to our understanding of gut renewal and repair.

15.
Environ Res ; 259: 119562, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38971360

RESUMEN

Elucidating the formation mechanism of plastisphere antibiotic resistance genes (ARGs) on different polymers is necessary to understand the ecological risks of plastisphere ARGs. Here, we explored the turnover and assembly mechanism of plastisphere ARGs on 8 different microplastic polymers (4 biodegradable (bMPs) and 4 non-biodegradable microplastics (nMPs)) by metagenomic sequencing. Our study revealed the presence of 479 ARGs with abundance ranging from 41.37 to 58.17 copies/16S rRNA gene in all plastispheres. These ARGs were predominantly multidrug resistance genes. The richness of plastisphere ARGs on different polymers had a significant correlation with the contribution of species turnover to plastisphere ARGs ß diversity. Furthermore, polymer type was the most critical factor affecting the composition of plastisphere ARGs. More opportunistic pathogens carrying diverse ARGs on BMPs (PBAT, PBS, and PHA) with higher horizontal gene transfer potential may further magnify the ecological risks and human health threats. For example, the opportunistic pathogens Riemerella anatipestifer, Vibrio campbellii, and Vibrio cholerae are closely related to human production and life, which were the important potential hosts of many plastisphere ARGs and mobile genetic elements on BMPs. Thus, we emphasize the urgency of developing the formation mechanism of plastisphere ARGs and the necessity of controlling BMPs and ARG pollution, especially BMPs, with ever-increasing usage in daily life.


Asunto(s)
Microplásticos , Microplásticos/toxicidad , Farmacorresistencia Microbiana/genética , Bacterias/genética , Bacterias/efectos de los fármacos , Genes Bacterianos
16.
Phys Chem Chem Phys ; 26(31): 20820-20827, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39044533

RESUMEN

Magnetic refrigeration based on the magnetocaloric effect is gaining interest in orthogonal or hexagonal rare-earth manganite. However, a more comprehensive understanding of the underlying mechanism is still required. We grew a high-quality single crystal of Dy0.5Ho0.5MnO3 using the optical floating zone method, since the parent crystals DyMnO3 and HoMnO3 have orthogonal and hexagonal structures, respectively. The magnetic and magnetocaloric properties and refrigeration mechanisms are thoroughly investigated. Doping modifies the magnetism according to the results obtained from the investigation of magnetic and dielectric properties and heat capacity. The spin reorientation transition shifts towards low temperature in comparison to HoMnO3. Near the Néel temperature of rare-earth sublattices (5 K), the highest changes in negative magnetic entropy under 0-70 kOe are 18 J kg-1 K-1 and 13 J kg-1 K-1 along the a- and c-axes, respectively. The low-temperature metamagnetic phase transition caused by the alterations in the magnetic symmetry of Ho3+ contributes to an increased magnetocaloric effect in comparison to the parent crystals, rendering it a promising choice for magnetic refrigeration applications. Dy0.5Ho0.5MnO3 exhibits a clear magnetocrystalline anisotropy with enhanced refrigeration capacity and negative magnetic entropy change along the a-axis. The adiabatic temperature change of Dy0.5Ho0.5MnO3 is 8.5 K, larger than that of HoMnO3, rendering it a promising choice for low-temperature magnetic refrigeration applications.

17.
Int J Mol Sci ; 25(11)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38891830

RESUMEN

The dynamic process of Drosophila spermatogenesis involves asymmetric division, mitosis, and meiosis, which ultimately results in the production of mature spermatozoa. Disorders of spermatogenesis can lead to infertility in males. ADAR (adenosine deaminase acting on RNA) mutations in Drosophila cause male infertility, yet the causative factors remain unclear. In this study, immunofluorescence staining was employed to visualize endogenous ADAR proteins and assess protein levels via fluorescence-intensity analysis. In addition, the early differentiation disorders and homeostatic alterations during early spermatogenesis in the testes were examined through quantification of transit-amplifying region length, counting the number of GSCs (germline stem cells), and fertility experiments. Our findings suggest that deletion of ADAR causes testicular tip transit-amplifying cells to accumulate and become infertile in older male Drosophila. By overexpressing ADAR in early germline cells, male infertility can be partially rescued. Transcriptome analysis showed that ADAR maintained early spermatogenesis homeostasis through the bone-morphogenetic-protein (BMP) signaling pathway. Taken together, these findings have the potential to help explore the role of ADAR in early spermatogenesis.


Asunto(s)
Adenosina Desaminasa , Proteínas Morfogenéticas Óseas , Proteínas de Drosophila , Drosophila melanogaster , Transducción de Señal , Espermatogénesis , Animales , Masculino , Espermatogénesis/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Adenosina Desaminasa/metabolismo , Adenosina Desaminasa/genética , Proteínas Morfogenéticas Óseas/metabolismo , Proteínas Morfogenéticas Óseas/genética , Infertilidad Masculina/genética , Infertilidad Masculina/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Testículo/metabolismo
18.
Cell Prolif ; : e13686, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38831624

RESUMEN

The in-depth mechanisms of microRNA regulation of premature ovarian failure (POF) remain unclear. Crispr-cas9 technology was used to construct transgenic mice. The qPCR and Western blot was used to detect the expression level of genes. H&E staining were used to detect ovarian pathological phenotypes. We found that the expression levels of microRNA-3061 were significantly higher in ovarian granulosa cells (OGCs) of POF mouse models than in controls. The miR-3061+/-/AMH-Cre+/- transgenic mice manifested symptoms of POF. RNA-Seq and luciferase reporter assay confirmed that the PAX7 was one of the target genes negatively regulated by microRNA-3061 (miR-3061-5p). Moreover, PAX7 mediated the expression of non-canonical Wnt/Ca2+ signalling pathway by binding to the motifs of promoters to stimulate the transcriptional activation of Wnt5a and CamK2a. In contrast, specific knock-in of microRNA-3061 in OGCs significantly downregulated the expression levels of PAX7 and inhibited the expression of downstream Wnt/Ca2+ signalling pathway. We also discerned a correlation between the expression levels of mRNAs of the Wnt/Ca2+ signalling pathway and the levels of E2 and FSH in POF patients by examining gene expression in the follicular fluid-derived exosomes of women. We confirmed that overexpression of microRNA-3061 induced proliferative inhibition of OGCs and ultimately induced POF in mice by suppressing the transcription factor PAX7 and downregulating expression levels of its downstream Wnt/Ca2+ signalling pathway genes.

19.
Cancer Med ; 13(12): e7224, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38888366

RESUMEN

BACKGROUND: Patients with DNA mismatch repair-proficient/microsatellite stable (pMMR/MSS) colorectal cancer (CRC), which accounts for 85% of all CRC cases, display a poor respond to immune checkpoint inhibitors (i.e., anti-PD-1 antibodies). pMMR/MSS CRC patients with locally advanced cancers need effective combined therapies. METHODS: In this pilot study, we administered six preoperative doses of each 2-week cycle of the anti-PD-1 antibody sintilimab (at a fixed dose of 200 mg), oxaliplatin, and 5-FU/CF (mFOLFOX6) combined with five doses of bevacizumab (the number of doses was reduced to prevent surgical delays) to patients with cT4NxM0 colon or upper rectal cancers. And radical surgery was performed approximately 2 weeks after the last dose of neoadjuvant therapy. The primary endpoint was a pathologic complete response (pCR). We also evaluated major pathologic response (MPR, ≤10% residual viable tumor), radiological and pathological regression, safety, and tumor mutation burden (TMB), and tumor microenvironment (TME) characteristics. RESULTS: By the cutoff date (September 2023), 22 patients with cT4NxM0 pMMR/MSS colon or upper rectal cancers were enrolled and the median follow-up was 24.7 months (IQR: 21.1-26.1). All patients underwent R0 surgical resection without treatment-related surgical delays. pCR occurred in 12 of 22 resected tumors (54.5%) and MPR occurred in 18 of 22 (81.8%) patients. At the cutoff date, all patients were alive, and 21/22 were recurrence-free. Treatment-related adverse events of grade 3 or higher occurred in of 2/22 (9.1%) patients. Among the pCR tumors, two were found to harbor POLE mutations. The degree of pathological regression was significantly greater than that of radiological regression (p = 1.35 × 10-8). The number of CD3+/CD4+ cells in the tumor and stroma in pretreated biopsied tissues was markedly lower in pCR tumors than in non-pCR tumors (p = 0.038 and p = 0.015, respectively). CONCLUSIONS: Neoadjuvant sintilimab combined with bevacizumab and mFOLFOX6 was associated with few side effects, did not delay surgery, and led to pCR and non-pCR in 54.5% and 81.8% of the cases, respectively. Downregulation of CD3/CD4 expression in the tumor and stroma is related to pCR. However, the molecular mechanisms underlying PD-1 blockade-enhanced targeted chemotherapy require further investigation.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Bevacizumab , Neoplasias Colorrectales , Fluorouracilo , Inhibidores de Puntos de Control Inmunológico , Humanos , Masculino , Femenino , Persona de Mediana Edad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Anciano , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Fluorouracilo/uso terapéutico , Fluorouracilo/administración & dosificación , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Proyectos Piloto , Bevacizumab/uso terapéutico , Bevacizumab/administración & dosificación , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Leucovorina/uso terapéutico , Leucovorina/administración & dosificación , Reparación de la Incompatibilidad de ADN , Adulto , Inestabilidad de Microsatélites , Oxaliplatino/uso terapéutico , Oxaliplatino/administración & dosificación , Terapia Neoadyuvante/métodos , Microambiente Tumoral/inmunología , Compuestos Organoplatinos/uso terapéutico , Compuestos Organoplatinos/administración & dosificación , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Resultado del Tratamiento
20.
Adv Sci (Weinh) ; 11(28): e2402162, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38708715

RESUMEN

High-performance soft magnetic materials are important for energy conservation and emission reduction. One challenge is achieving a combination of reliable temperature stability, high resistivity, high Curie temperature, and high saturation magnetization in a single material, which often comes at the expense of intrinsic coercivity-a typical trade-off in the family of soft magnetic materials with homogeneous microstructures. Herein, a nanostructured FeCoNiSiAl complex concentrated alloy is developed through a hierarchical structure strategy. This alloy exhibits superior soft magnetic properties up to 897 K, maintaining an ultra-low intrinsic coercivity (13.6 A m-1 at 297 K) over a wide temperature range, a high resistivity (138.08 µΩ cm-1 at 297 K) and the saturation magnetization with only a 16.7% attenuation at 897 K. These unusual property combinations are attributed to the dual-magnetic-state nature with exchange softening due to continuous crystal ordering fluctuations at the atomic scale. By deliberately controlling the microstructure, the comprehensive performance of the alloy can be tuned and controlled. The research provides valuable guidance for the development of soft magnetic materials for high-temperature applications and expands the potential applications of related functional materials in the field of sustainable energy.

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