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1.
Diabetol Metab Syndr ; 16(1): 98, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38715117

RESUMEN

BACKGROUND: Emerging evidence indicates carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is involved in the development of atherosclerosis (AS). However, the roles and functions of CEACAM1 in AS remain unknown. Therefore, this study aims to investigate the roles and molecular functions of CEACAM1 in AS. METHODS: We constructed a diabetes mellitus (DM) + high-fat diet (HFD) mouse model based on the streptozotocin (STZ)-induced apolipoprotein E-knockdown (ApopE-/-) mouse to investigate the roles and regulatory mechanism of miR-449a/CEACAM1 axis. The mRNA expression and protein levels in this study were examined using quantity PCR, western blot, immunofluorescence (IF), enzyme-linked immunosorbent assay (ELISA), and immunohistochemistry (IHC), respectively. And the lipid deposition and collagen content were detected using Oil Red O and Sirius Red staining. Cell apoptosis, migration, invasion, and tuber formation were detected by Annexin-V FITC/PI, wound healing, transwell, and tuber formation assays, respectively. The relationship between miR-449a and CEACAM1 was determined by a dual-luciferase reporter gene assay. RESULTS: miR-449a and MMP-9 were upregulated, and CEACAM1 was downregulated in the DM + HFD MOUSE model. Upregulation of CEACAM1 promoted atherosclerotic plaque stability and inhibited inflammation in the DM + HFD mouse model. And miR-449a directly targeted CEACAM1. Besides, miR-449a interacted with CEACAM1 to regulate atherosclerotic plaque stability and inflammation in DM-associated AS mice. In vitro, the rescue experiments showed miR-449a interacted with CEACAM1 to affect apoptosis, migration, invasion, and tuber formation ability in high glucose (HG)-induced HUVECs. CONCLUSION: These results demonstrated that miR-449a promoted plaque instability and inflammation in DM and HFD-induced mice by targeting CEACAM1.

2.
Heliyon ; 10(9): e30603, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38726149

RESUMEN

Objectives: Epithelial ovarian cancer (EOC) is considered to be a prevalent female malignancy with both high incidence and mortality. It is reported that RNA-binding protein 3 (RBMS3) executives a tumor suppressor function in different cancers. This investigation was designed to examine the expression of RBMS3 in epithelial ovarian cancer, the effects on EOC cells, and its connection to immune cells that infiltrate tumors in the EOC microenvironment. Methods: The expression levels of RBMS3 in EOC tissues as well as their correlations with immune cell infiltration and clinical outcome were examined using bioinformatics approaches. Western blotting as well as immunohistochemistry were carried out to determine the protein levels in EOC tissues. In addition, qRT-PCR was employed to look at the expression of the mRNA. The role of RBMS3 in EOC cells was investigated, and an RBMS3 lentiviral vector was developed. The effects of RBMS3 on subcutaneous tumor development, the proliferation protein Ki-67, the tumor angiogenesis indicator CD31, and its function in controlling the tumor immune microenvironment were evaluated by in vivo tests. Results: There was a considerable decrease in RBMS3 expression in EOC tissues, which was linked to a poor prognosis for patients and the infiltration of multiple immune cell. Given immunohistochemical studies, tissues with increased RBMS3 expression had decreased markers of myeloid-derived suppressor cells, regulatory T cells, and M2 macrophages, whereas M1 macrophage markers were elevated. RBMS3 appears to suppress the capabilities of proliferating, invading, and migrating in EOC cells according to in vitro tests, whereas tumors overexpressing RBMS3 developed more slowly in syngeneic mouse models. The overexpression of RBMS3 led to a decline in the levels of Ki-67 protein and CD31. Additionally, it showed a negatively correlation with markers of regulatory T cell, myeloid-derived suppressor cell, and M2 macrophage but a positive correlation with markers of M1 macrophage. Conclusions: The findings revealed that elevated RBMS3 expression plays a tumor suppressor role in EOC and was connected to patient survival in EOC. The studies conducted in vitro and in vivo demonstrated a link between RBMS3 expression and the infiltration of certain immune cells, indicating a function for RBMS3 in the immunosuppressive tumor microenvironment and its promising efficiency as a novel target for immunotherapy against EOC.

3.
Scand J Occup Ther ; 31(1): 2348816, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38728597

RESUMEN

BACKGROUND: Preliminary evidence of the content validity of the simplified Chinese version of 'Picture My Participation' (PMP-C; Simplified) items and reliability of the subscale attendance for the effectiveness of the use with children and youth in mainland China has been collected. However, evidence of construct validity for the instrument is not yet available. AIM: To explore the construct validity of the attendance scale in PMP-C (Simplified). METHODS: A cross-sectional study using convenience sampling was conducted using PMP-C (Simplified) with a picture-supported interview for 290 children and youths aged 5-21 with and without ID in urban and rural areas of mainland China. Exploratory factor analysis (EFA) was performed using the principal component analysis (PCA) to analyse the resulting data. RESULTS: The EFA extracted five factors with eigenvalues greater than one and the cumulative contribution rate of factors accounted for 51.62% of the variance. All items had factor loadings above 0.50. The five subcomponents included: organised activities, social activities, taking care of others, family life activities and personal care and development activities. CONCLUSION: The results of the factor analysis support the construct validity of the PMP-C (Simplified) attendance scale. It provides further psychometric evidence that PMP-C (Simplified) is a sound measure to assess participation for children and youths in mainland China.


Asunto(s)
Psicometría , Humanos , Masculino , Estudios Transversales , Femenino , China , Niño , Adolescente , Reproducibilidad de los Resultados , Adulto Joven , Análisis Factorial , Encuestas y Cuestionarios , Preescolar , Participación Social , Terapia Ocupacional
4.
Cancer Lett ; : 216951, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38734159

RESUMEN

Neoadjuvant immunotherapy represents promising strategy in the treatment of esophageal squamous cell carcinoma (ESCC). However, the mechanisms underlying its impact on treatment sensitivity or resistance remain a subject of controversy. In this study, we conducted single-cell RNA and T/B cell receptor (scTCR/scBCR) sequencing of CD45+ immune cells on samples from 10 patients who received neoadjuvant immunotherapy and chemotherapy. We also validated our findings using multiplexed immunofluorescence and analyzed bulk RNA-seq from other cohorts in public database. By integrating analysis of 87357 CD45+ cells, we found GZMK+ effector memory T cells were relatively enriched and CXCL13+ exhausted T cells and regulator T cells decreased among responders, indicating a persistent anti-tumor memory process. Additionally, the enhanced presence of BCR expansion and somatic hypermutation process within TNFRSF13B+ memory B cells suggested their roles in antigen presentation. This was further corroborated by the evidence of the T-B co-stimulation pattern and CXCL13-CXCR5 axis. The complexity of myeloid cell heterogeneity was also particularly pronounced. The elevated expression of S100A7 in ESCC, as detected by bulk RNA-seq, was associated with an exhausted and immunosuppressive tumor microenvironment. In summary, this study has unveiled a potential regulatory network among immune cells and the clonal dynamics of their functions, and the mechanisms of exhaustion and memory conversion between GZMK+ Tem and TNFRSF13B+ Bmem from antigen presentation and co-stimulation perspectives during neoadjuvant PD-1 blockade treatment in ESCC.

5.
Nat Neurosci ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38741020

RESUMEN

The subcommissural organ (SCO) is a gland located at the entrance of the aqueduct of Sylvius in the brain. It exists in species as distantly related as amphioxus and humans, but its function is largely unknown. Here, to explore its function, we compared transcriptomes of SCO and non-SCO brain regions and found three genes, Sspo, Car3 and Spdef, that are highly expressed in the SCO. Mouse strains expressing Cre recombinase from endogenous promoter/enhancer elements of these genes were used to genetically ablate SCO cells during embryonic development, resulting in severe hydrocephalus and defects in neuronal migration and development of neuronal axons and dendrites. Unbiased peptidomic analysis revealed enrichment of three SCO-derived peptides, namely, thymosin beta 4, thymosin beta 10 and NP24, and their reintroduction into SCO-ablated brain ventricles substantially rescued developmental defects. Together, these data identify a critical role for the SCO in brain development.

6.
Artículo en Inglés | MEDLINE | ID: mdl-38763304

RESUMEN

OBJECTIVE: Accurately predicting response during neoadjuvant chemoimmunotherapy for resectable non-small cell lung cancer (NSCLC) remains clinically challenging. In this study, we investigate the effectiveness of blood-based tumor mutational burden (bTMB) and a deep learning (DL) model in predicting major pathologic response (MPR) and survival from a phase II trial. METHODS: Blood samples were prospectively collected from 45 stage IIIA (N2) NSCLC patients undergoing neoadjuvant chemoimmunotherapy. An integrated model, combining the CT-based DL score, bTMB, and clinical factors, was developed to predict tumor response to neoadjuvant chemoimmunotherapy. RESULTS: At baseline, bTMB were detected in 77.8% (35 of 45) of patients. Baseline bTMB ≥11 Muts/Mb was associated with significantly higher MPR rates (77.8% vs. 38.5%, p = 0.042), and longer disease-free survival (DFS, p = 0.043), but not overall survival (p = 0.131), compared to bTMB < 11 Muts/Mb in 35 patients with bTMB available. The developed DL model achieved an area under the curve (AUC) of 0.703 in all patients. Importantly, the predictive performance of the integrated model improved to an AUC of 0.820 when combining the DL score with bTMB and clinical factors. Baseline circulating tumor DNA (ctDNA) status was not associated with pathological response and survival. Compared to ctDNA residual, ctDNA clearance before surgery was associated with significantly higher MPR rates (88.2% vs. 11.1%, p < 0.001) and improved DFS (p = 0.010). CONCLUSIONS: The integrated model shows promise as a predictor of tumor response to neoadjuvant chemoimmunotherapy. Serial ctDNA dynamics provide a reliable tool for monitoring tumor response.

7.
Med Princ Pract ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38772352

RESUMEN

Hepatocellular carcinoma (HCC), the most prevalent form of liver cancer globally, poses a substantial health burden. HCC development is influenced by multiple risk factors including hepatitis B and C infections, excessive alcohol consumption, nonalcoholic steatohepatitis (NASH), and demographic variables like gender, race, and age. Although the exact etiology of HCC is not fully understood, HCC formation is a multi-step process that is contributed by the interplays of viral infection, hepatocyte oncogenic mutations, and chronic liver diseases such as alcoholic cirrhosis and NASH. Disease stage significantly impacts HCC prognosis, with 5-year survival rates ranging from 36% in early-stage cases to 13% in late-stage metastatic cases. Therefore, there is significant potential for life-saving and socioeconomic benefits through the implementation of surveillance programs and the introduction of low-cost screening measures for high-risk groups, such as ultrasound imaging and blood tests. Treatment options for HCC encompass surgery, liver transplantation, radiation therapy, chemotherapy, targeted therapy, and immunotherapy. Despite therapeutic advances, the treatment of advanced HCC remains a challenge. The prognosis of advanced HCC could be greatly improved with continued efforts in prevention, early detection, and treatment development. These efforts will ultimately lead to improved patient outcomes and increased chances of long-term survival.

8.
Inorg Chem ; 63(19): 8750-8763, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38693869

RESUMEN

Using a quinoline substituted Qsal ligand, Hqsal-5-Brq (Hqsal-5-Brq = N-(5-bromo-8-quinolyl)salicylaldimine), four FeIII complexes, [Fe(qsal-5-Brq)2]A·CH3OH (Y = NO3- (1NO3), BF4- (2BF4), PF6- (3PF6), OTf- (4OTf), were prepared and characterized. Structure analysis revealed that complex 2BF4 contained two species (2BF4(P1̅) and 2BF4(C2/c)). In these compounds except 3PF6, the [Fe(qsal-5-Brq)2]+ cations form 1D chains through π-π interactions and other weak interactions. Adjacent chains are connected to form the 2D "Chain Layer" structures and 3D structures through various supramolecular interactions. For 3PF6, a "Dimer Chain" structure is formed from the loosely connected dimers. Magnetic studies revealed that compounds 1NO3 and 2BF4(P1̅) displayed abrupt hysteretic SCO with the transition temperature T1/2↓ = 235 K, T1/2↑ = 240 K for 1NO3 and T1/2↓ = 230 K, T1/2↑ = 235 K for 2BF4(P1̅), while compounds 3PF6 and 4OTf are in the HS state. Desolvation of the complexes significantly modifies their SCO properties: the desolvated 1NO3 and 2BF4 show a gradual SCO, desolvated 3PF6 undergoes a two-step SCO, and desolvated 4OTf exhibits a hysteretic transition. Overall, this work reported the FeIII-SCO complexes of the quinoline-substituted Hqsal ligand and highlighted the potential of these ligands for the development of interesting FeIII-SCO materials.

9.
Front Oncol ; 14: 1391546, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38764577

RESUMEN

Objectives: The objective of this network meta-analysis is to systematically compare the efficacy of diverse progestin-based combination regimens in treating patients diagnosed with endometrial cancer or atypical endometrial hyperplasia. The primary goal is to discern the optimal combination treatment regimen through a comprehensive examination of their respective effectiveness. Methods: We systematically searched four prominent databases: PubMed, Web of Science, Embase, and Cochrane Central Register of Controlled Trials, for randomized controlled trials addressing the efficacy of progestins or progestin combinations in the treatment of patients with endometrial cancer or atypical endometrial hyperplasia. The search spanned from the inception of these databases to December 2023. Key outcome indicators encompassed survival indices, criteria for assessing efficacy, as well as pregnancy and relapse rate. This study was registered in PROSPERO (CRD42024496311). Results: From the 1,558 articles initially retrieved, we included 27 studies involving a total of 5,323 subjects in our analysis. The results of the network meta-analysis revealed that the mTOR inhibitor+megestrol acetate (MA)+tamoxifen regimen secured the top rank in maintaining stable disease (SD) (SUCRA=73.4%) and extending progression-free survival (PFS) (SUCRA=72.4%). Additionally, the progestin combined with tamoxifen regimen claimed the leading position in enhancing the partial response (PR) (SUCRA=75.2%) and prolonging overall survival (OS) (SUCRA=80%). The LNG-IUS-based dual progestin regimen emerged as the frontrunner in improving the complete response (CR) (SUCRA=98.7%), objective response rate (ORR) (SUCRA=99.1%), pregnancy rate (SUCRA=83.7%), and mitigating progression (SUCRA=8.0%) and relapse rate (SUCRA=47.4%). In terms of safety, The LNG-IUS-based dual progestin regimen had the lowest likelihood of adverse events (SUCRA=4.2%), while the mTOR inhibitor regimen (SUCRA=89.2%) and mTOR inbitor+MA+tamoxifen regimen (SUCRA=88.4%) had the highest likelihood of adverse events. Conclusions: Patients diagnosed with endometrial cancer or atypical endometrial hyperplasia exhibited the most favorable prognosis when undergoing progestin combination therapy that included tamoxifen, mTOR inhibitor, or LNG-IUS. Notably, among these options, the LNG-IUS-based dual progestin regimen emerged as particularly promising for potential application. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO, identifier CRD42024496311.

10.
Front Vet Sci ; 11: 1376678, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38764852

RESUMEN

Porcine idiopathic vesicular disease (PIVD), one of several clinically indistinguishable vesicular diseases of pigs, is caused by the emerging pathogen Senecavirus A (SVA). Despite the widespread prevalence of porcine SVA infection, no effective commercial vaccines for PIVD prevention and control are available, due to high costs associated with vaccine testing in pigs, considerable SVA diversity, and SVA rapid evolution. In this study, SVA CH/JL/2022 (OP562896), a novel mutant SVA strain derived from an isolate obtained from a pig farm in Jilin Province, China, was inactivated then combined with four adjuvants, MONTANIDETM GEL02 PR (GEL 02), MONTANIDETM ISA 201 VG (ISA 201), MONTANIDETM IMG 1313 VG N (IMS1313), or Rehydragel LV (LV). The resulting inactivated SVA CH/JL/2022 vaccines were assessed for efficacy in mice and found to induce robust in vivo lymphocyte proliferation responses and strong IgG1, IgG2a, and neutralizing antibody responses with IgG2a/IgG1 ratios of <1. Furthermore, all vaccinated groups exhibited significantly higher levels of serum cytokines IL-2, IL-4, IL-6, and IFN as compared to unvaccinated mice. These results indicate that all vaccines elicited both Th1 and Th2 responses, with Th2 responses predominating. Moreover, vaccinated mice exhibited enhanced resistance to SVA infection, as evidenced by reduced viral RNA levels and SVA infection-induced histopathological changes. Collectively, our results demonstrate that the SVA-GEL vaccine induced more robust immunological responses in mice than did the other three vaccines, thus highlighting the potential of SVA-GEL to serve an effective tool for preventing and controlling SVA infection.

11.
Heliyon ; 10(9): e30668, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38774097

RESUMEN

Objective: To analyse and continually improve existing issues in the quality improvement process of medical linear accelerators (LINACs) and enhance the quality control management of LINACs. Methods: Data were collected from eight LINACs (sourced from three manufacturers) at Zhejiang Cancer Hospital using Excel diaries between January 2019 and December 2020. The data description and analysis were performed using the analytic hierarchy process, SPSSAU and Excel software, and mean-time-to-repair (MTTR)/mean-time-between-failure (MTBF) metrics. Continuous quality improvement was executed using the quality control circle (QCC) quality management method. Results: After quality improvement, the risk frequency of 'LINAC down' events decreased by 43.63% and downtime was reduced by 40.45%. The weight of downtime risk improved by 73.69%. The MTTR recovery value increased by 31.90%, and MTBF reliability increased by 2.97 h. The simulation results demonstrated that the proposed quality improvement measures could effectively decrease the frequency and duration of downtimes, consequently extending the normal operational time of LINACs. Conclusion: Transitioning from instant repair to preventative maintenance can enhance the operational efficiency of equipment and yield economic benefits for hospitals. The QCC method and the event risk evaluation model are effective in reducing the downtime of LINACs and improving their quality control management.

12.
Front Immunol ; 15: 1381061, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38774877

RESUMEN

Background: Thyroid immune-related adverse events (irAEs) associated with immune checkpoint inhibitor (ICI) treatment appear to correlate with a better prognosis. We aimed to investigate clinical biomarkers associated with thyroid irAEs. Methods: We retrospectively analyzed data from 129 patients receiving programmed cell death protein 1 (PD-1) inhibitors for stage III and IV gastrointestinal tumors. Patients were divided into two groups: "thyroid irAEs" group and "no thyroid irAEs" group. We compared continuous variables using Mann-Whitney U and Kruskal-Wallis tests and categorical variables using Pearson's chi-square test. Survival curves were generated using the Kaplan-Meier method, and associations between clinical features and thyroid irAEs were assessed using univariate and multivariate logistic regression models. Associations for thyroid irAEs and outcomes [progression-free survival (PFS), overall survival (OS)] of the patients were performed with a Cox proportional hazard model. Results: A total of 129 patients, including 66 gastric cancer, 30 esophageal squamous cell carcinoma, and 33 hepatocellular carcinoma (HCC), were involved in this analysis with 47 cases of thyroid irAEs occurrence. The Cox proportional hazard model analysis confirmed the extended PFS [hazard rate (HR) = 0.447, 95% confidence interval (CI): 0.215 to 0.931, p = 0.031] and OS (HR = 0.424, 95% CI: 0.201 to 0.893, p = 0.024) for thyroid irAEs group when compared with those of the no thyroid irAEs group. Association between thyroid irAEs and clinical characteristics at baseline was analyzed subsequently by univariate analysis. Higher body mass index (p = 0.005), increased eosinophil count (p = 0.014), increased lactate dehydrogenase (p = 0.008), higher baseline thyroid stimulating hormone (TSH) (p = 0.001), HCC (p = 0.001) and increased adenosine deaminase (ADA) (p = 0.001) were linked with thyroid irAEs occurrence. The multivariable logistic regression model indicated that ADA [odds rate (OR) = 4.756, 95% CI: 1.147 to 19.729, p = 0.032] was independently associated with thyroid irAEs occurrence. Conclusions: Increased baseline level of ADA was associated with thyroid irAEs occurrence in patients with advanced gastrointestinal tumors who received ICI treatment. In the case of abnormal ADA, attention should be paid to the risk of thyroid irAEs.


Asunto(s)
Neoplasias Gastrointestinales , Inhibidores de Puntos de Control Inmunológico , Estadificación de Neoplasias , Humanos , Femenino , Masculino , Neoplasias Gastrointestinales/inmunología , Neoplasias Gastrointestinales/tratamiento farmacológico , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Adulto , Glándula Tiroides/patología , Glándula Tiroides/inmunología , Glándula Tiroides/metabolismo , Pronóstico , Biomarcadores de Tumor
13.
J Am Chem Soc ; 146(20): 14278-14286, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38727720

RESUMEN

The development of catalysts serves as the cornerstone of innovation in synthesis, as exemplified by the recent discovery of photoenzymes. However, the repertoire of naturally occurring enzymes repurposed by direct light excitation to catalyze new-to-nature photobiotransformations is currently limited to flavoproteins and keto-reductases. Herein, we shed light on imine reductases (IREDs) that catalyze the remote C(sp3)-C(sp3) bond formation, providing a previously elusive radical hydroalkylation of enamides for accessing chiral amines (45 examples with up to 99% enantiomeric excess). Beyond their natural function in catalyzing two-electron reductive amination reactions, upon direct visible-light excitation or in synergy with a synthetic photoredox catalyst, IREDs are repurposed to tune the non-natural photoinduced single-electron radical processes. By conducting wet mechanistic experiments and computational simulations, we unravel how engineered IREDs direct radical intermediates toward the productive and enantioselective pathway. This work represents a promising paradigm for harnessing nature's catalysts for new-to-nature asymmetric transformations that remain challenging through traditional chemocatalytic methods.

14.
Adv Healthc Mater ; : e2401160, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38757919

RESUMEN

To solve the problems of slow regeneration and mismatch of axon regeneration after peripheral nerve injury, nerve guidance conduits (NGCs) have been widely used to promote nerve regeneration. Multichannel NGCs have been widely studied to mimic the structure of natural nerve bundles. However, multichannel conduits are prone to structural instability. Thermo-responsive shape memory polymers (SMPs) can maintain a persistent initial structure over the body temperature range. Electrical stimulation (ES), utilized within nerve NGCs, serves as a biological signal to expedite damaged nerve regeneration. Here, we designed an electrospun shape-persistent conductive NGC to maintain the persistent tubular structure in the physiological temperature range and improve the conductivity. The physicochemical and biocompatibility of these P, P/G, P/G-GO, and P/G-RGO NGCs were conducted in vitro. Meanwhile, to evaluate biocompatibility and peripheral nerve regeneration, NGCs were implanted in subcutaneous parts of the back of rats and sciatic nerves assessed by histology and immunofluorescence analyses. The conductive NGC displayed a stable structure, good biocompatibility and promoted nerve regeneration. Collectively, the shape-persistent conductive NGC (P/G-RGO) is expected to promote peripheral nerve recovery, especially for long-gap and large-diameter nerves. This article is protected by copyright. All rights reserved.

15.
Sci Total Environ ; 931: 172926, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38697519

RESUMEN

Flash droughts characterized by rapid onset and intensification are expected to be a new normal under climate change and potentially affect vegetation photosynthesis and terrestrial carbon sink. However, the effects of flash drought on vegetation photosynthesis and their potential dominant driving factors remain uncertain. Here, we quantify the susceptibility and response magnitude of vegetation photosynthesis to flash drought across different ecosystems (i.e., forest, shrubland, grassland, and cropland) in China based on reanalysis and satellite observations. By employing the extreme gradient boosting model, we also identify the dominant factors that influence these flash drought-photosynthesis relationships. We show that over 51.46 % of ecosystems across China are susceptible to flash drought, and grasslands are substantially suppressed, as reflected in both sensitivity and response magnitude (with median gross primary productivity anomalies of -0.13). We further demonstrate that background climate differences (e.g., mean annual temperature and aridity) predominantly regulate the response variation in forest and shrubland, with hotter/colder or drier ecosystems being more severely suppressed by flash drought. However, in grasslands and croplands, the differential vegetation responses are attributed to the intensity of abnormal hydro-meteorological conditions during flash drought (e.g., vapor pressure deficit (VPD) and temperature anomalies). The effects of flash droughts intensify with increasing VPD and nonmonotonically relate to temperature, with colder or hotter temperatures leading to more severe vegetation loss. Our results identify the vulnerable ecological regions under flash drought and enable a better understanding of vegetation photosynthesis response to climate extremes, which may be useful for developing effective management strategies.


Asunto(s)
Cambio Climático , Sequías , Ecosistema , Fotosíntesis , China , Bosques
16.
Eur J Surg Oncol ; 50(7): 108362, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38704899

RESUMEN

OBJECTIVE: This study aims to establish a machine learning (ML) model for predicting the risk of liver and/or lung metastasis in colorectal cancer (CRC). METHODS: Using the National Institutes of Health (NIH)'s Surveillance, Epidemiology, and End Results (SEER) database, a total of 51265 patients with pathological diagnosis of colorectal cancer from 2010 to 2015 were extracted for model development. On this basis, We have established 7 machine learning algorithm models. Evaluate the model based on accuracy, and AUC of receiver operating characteristics (ROC) and explain the relationship between clinical pathological features and target variables based on the best model. We validated the model among 196 colorectal cancer patients in Beijing Electric Power Hospital of Capital Medical University of China to evaluate its performance and universality. Finally, we have developed a network-based calculator using the best model to predict the risk of liver and/or lung metastasis in colorectal cancer patients. RESULTS: 51265 patients were enrolled in the study, of which 7864 (15.3 %) had distant liver and/or lung metastasis. RF had the best predictive ability, In the internal test set, with an accuracy of 0.895, AUC of 0.956, and AUPR of 0.896. In addition, the RF model was evaluated in the external validation set with an accuracy of 0.913, AUC of 0.912, and AUPR of 0.611. CONCLUSION: In this study, we constructed an RF algorithm mode to predict the risk of colorectal liver and/or lung metastasis, to assist doctors in making clinical decisions.

17.
Water Res ; 257: 121683, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38703542

RESUMEN

Efficient uranium capture from wastewater holds great importance for the environmental remediation and sustainable development of nuclear energy, but it is a tremendous challenge. Herein, a facile and scalable approach is reported to fabricate functionalized hierarchical porous polymers (PPN-3) decorated with high density of phosphate groups for uranium adsorption. The as-constructed hierarchical porous structure could allow rapid diffusion of uranyl ions, while abundant phosphate groups that serve as adsorption sites could provide the high affinity for uranyl. Consequently, PPN-3 shows a high uranium adsorption uptake of 923.06 mg g-1 and reaches adsorption equilibrium within simply 10 min in uranium-spiked aqueous solution. Moreover, PPN-3 affords selective adsorption of uranyl over multiple metal ions and possesses a rapid and high removal rate of U(VI) in real water systems. Furthermore, this study offers direct polymerization strategy for the cost-effective fabrication of phosphate-functionalized porous organic polymers, which may provide promising application potential for uranium extraction.

18.
J Oleo Sci ; 73(5): 657-664, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38692889

RESUMEN

This present work investigated the influence of black rice anthocyanins as antioxidants on the oxidation stability of oil. Malonic acid, succinic acid and succinic anhydride were grafted on black rice anthocyanins through acylation method to improve their antioxidant activity in oil. The results from fourier transform infrared spectroscopy (FTIR) showed new absorption peaks near 1744 cm -1 and 1514 cm -1 , which implied that malonic acid, succinic acid and succinic anhydride grafted on the -OH of glucoside and rutinoside through esterification reaction and resulted that the polarity of these were reduced. Total content of anthocyanin (TAC) decreased to 166. 3 mg/g, 163.7 mg/g and 150.2 mg/g, respectively after modification with succinic acid, malonic acid and succinic anhydride. Compared with native anthocyanins, the acylation of black rice anthocyanins partially reduced its antioxidant activity. In addition, DPPH clearance of molecular modified anthocyanins decreased to 62.6% (San-An). As revealed in the oil stability through the determination of primary oxidation products (PV) and secondary oxidation products (p-AV), Sa-An, Ma-An and San-An showed stronger antioxidant activity in Schaal oven accelerated oxidation test during 12 days than native black rice anthocyanin in both corn oil and flaxseed oil. Molecular modified black rice anthocyanins are expected to be used as colorants, antioxidants, etc. in oil-rich food.


Asunto(s)
Antocianinas , Antioxidantes , Oryza , Oxidación-Reducción , Antocianinas/química , Antocianinas/farmacología , Antioxidantes/farmacología , Oryza/química , Acilación , Aceites de Plantas/química , Aceites de Plantas/farmacología , Espectroscopía Infrarroja por Transformada de Fourier
19.
Angew Chem Int Ed Engl ; : e202407339, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714494

RESUMEN

Two-electron oxidative addition is one of the most important elementary reactions for d-block transition metals but it is uncommon for f-block elements. Here, we report the first examples of intermolecular oxidative addition of E-H (E = C, N) bonds to uranium(II) centers. The transient U(II) species was formed in-situ by reducing a heterometallic cluster featuring U(IV)-Pd(0) bonds with potassium-graphite (KC8). Oxidative addition of C-H or N-H bonds to the U(II) centers was observed when this transient U(II) species was treated with benzene, carbazole or 1-adamantylamine, respectively. The U(II) centers could also react with tetracene, biphenylene or N2O, leading to the formation of arene reduced U(IV) products and uranyl(VI) species via two- or four-electron processes. This study demonstrates that the intermolecular two-electron oxidative addition reactions are viable for actinide elements.

20.
J Hazard Mater ; 473: 134595, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38761769

RESUMEN

A biocatalytic system comprising fungal laccase and mediators can generate phenol radicals and efficiently eliminate various triarylmethane dyes. This study systematically explores the kinetic impact of dissolved organic matter (DOM), represented by humic substance (HS consisting of 90% fulvic acid, from lignite), on the decolorization of seven typical triarylmethane dyes by Trametes versicolor laccase and twenty natural mediators. Among these, 4-hydroxybenzyl alcohol (4-HA) and methyl violet (MV) undergo in-depth investigation regarding degradation products, pathways, and reaction mechanisms. In instances where HS hampers laccase-alone decolorization, such as malachite green, Coomassie brilliant blue, bromophenol blue, and acid magenta, this inhibition may persist despite mediator introduction. Conversely, in cases where HS facilitates decolorization, such as crystalline violet and ethyl violet, most laccase-mediator systems (LMSs) can still benefit. For MV decolorization by laccase and 4-HA, HS's kinetic effect is controlled by concentration and reaction time. A 5 mg/L HS increased the decolorization rate from 50% to 67% within the first hour, whereas 10 mg/L HS only achieved 45%. After 16 h of reaction, HS's impact on decolorization rate diminishes. Furthermore, the addition of HS enhances precipitation production, probably due to its involvement in polymerization with MV and mediator. Computational simulations and spectral monitoring reveal that low HS concentrations accelerate laccase-mediated demethylation by disrupting the chromophores bound to MV, thus promoting the decolorization of MV. Conversely, inhibition by high HS concentrations stems from the competitive binding of the enzyme pocket to the mediator, and the reduction of phenol free radicals in the system. Molecular docking and kinetic simulations revealed that laccase forms complexes with both the mediator and MV. Interestingly, the decolorization of MV occurred through a non-radical mechanism in the presence of HS. This work provided a reference for screening of high catalytic performance mediators to remove triarylmethane dyes in the actual water environment.

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