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1.
Immunity ; 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39226901

RESUMEN

Pro-inflammatory autoantigen-specific CD4+ T helper (auto-Th) cells are central orchestrators of autoimmune diseases (AIDs). We aimed to characterize these cells in human AIDs with defined autoantigens by combining human leukocyte antigen (HLA)-tetramer-based and activation-based multidimensional ex vivo analyses. In aquaporin4-antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD) patients, auto-Th cells expressed CD154, but proliferative capacity and pro-inflammatory cytokines were strongly reduced. Instead, exhaustion-associated co-inhibitory receptors were expressed together with FOXP3, the canonical regulatory T cell (Treg) transcription factor. Auto-Th cells responded in vitro to checkpoint inhibition and provided potent B cell help. Cells with the same exhaustion-like (ThEx) phenotype were identified in soluble liver antigen (SLA)-antibody-autoimmune hepatitis and BP180-antibody-positive bullous pemphigoid, AIDs of the liver and skin, respectively. While originally described in cancer and chronic infection, our data point to T cell exhaustion as a common mechanism of adaptation to chronic (self-)stimulation across AID types and link exhausted CD4+ T cells to humoral autoimmune responses, with implications for therapeutic targeting.

2.
Sci Adv ; 10(36): eadn3470, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39231218

RESUMEN

Regulatory T cells (Treg cells) hold promise for sustainable therapy of immune disorders. Recent advancements in chimeric antigen receptor development and genome editing aim to enhance the specificity and function of Treg cells. However, impurities and functional instability pose challenges for the development of safe gene-edited Treg cell products. Here, we examined different Treg cell subsets regarding their fate, epigenomic stability, transcriptomes, T cell receptor repertoires, and function ex vivo and after manufacturing. Each Treg cell subset displayed distinct features, including lineage stability, epigenomics, surface markers, T cell receptor diversity, and transcriptomics. Earlier-differentiated memory Treg cell populations, including a hitherto unidentified naïve-like memory Treg cell subset, outperformed late-differentiated effector memory-like Treg cells in regulatory function, proliferative capacity, and epigenomic stability. High yields of stable, functional Treg cell products could be achieved by depleting the small effector memory-like Treg cell subset before manufacturing. Considering Treg cell subset composition appears critical to maintain lineage stability in the final cell product.


Asunto(s)
Memoria Inmunológica , Linfocitos T Reguladores , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Humanos , Fenotipo , Células T de Memoria/inmunología , Células T de Memoria/metabolismo , Diferenciación Celular , Receptores de Antígenos de Linfocitos T/metabolismo , Transcriptoma
3.
J Clin Med ; 13(12)2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38930036

RESUMEN

Objectives: Gait speed indicates the individual's functional status and predicts overall health. This study aims to determine (1) the intra- and inter-rater and test-retest reliability of the dynamic 4 m gait speed test protocol; (2) establish the normative reference values of habitual and fast gait speeds in community-dwelling healthy Singaporean adults aged 21 to 80; and (3) explore the association of age, gender, height, weight, and body mass index (BMI) on gait speed. Methods: This prospective cross-sectional study recruited healthy ambulatory community-dwelling Singaporeans aged 21 to 80 who could ambulate independently without aid. Participants were excluded if they required walking aids; were pregnant; or had physical, medical, or cognitive conditions that may affect gait. Each participant completed at least two habitual and fast gait speed test trials via a 4 m walkway with a dynamic start. The data were analysed by descriptive statistics, the Mann-Whitney test, the Spearman coefficient, and the interclass correlation coefficient (ICC). Results: In total, 178 males and 201 females were included in the data analysis. The median age was 45.0 years [interquartile range (IQR) 26.2-59.0], and the median height was 1.64 metres (m) (IQR 1.58-1.70). The median habitual gait speed was 1.08 metre/second (m/s) (IQR 0.97-1.22), and the fast gait speed was 1.55 m/s (IQR 1.40-1.70). The ICC for reliability ranged from 0.84 to 0.99, indicating that the 4 m gait speed test had good-to-excellent reliability. Conclusions: Gait speeds were not influenced by gender but declined with age advancement. Age and height and age and BMI were weakly correlated to habitual and fast gait speed, respectively. We established the norm values for the 4 m gait speeds in Singapore and proved it to be a reliable gait speed assessment ready for immediate community applications.

4.
J Interferon Cytokine Res ; 44(3): 124-134, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38488759

RESUMEN

Feline interferon omega (IFN-ω) has been proven to have high antiviral activity; however, its in-depth antiviral effects remain unknown. Extracellular vesicles (EVs) have been demonstrated to participate in the regulation of the immune response pathway for the body through various active substances, especially through the microRNA (miRNA) carried by them. In this study, we isolated EVs from feline peripheral blood by differential centrifugation, and further found that the content of IFN-ω in EVs increased continuously within 24 h after IFN-ω treatment, and a large number of miRNAs were significantly downregulated in EVs within 12 h after IFN-ω treatment. These significantly differentially expressed miRNAs were important for regulating changes in antiviral cytokines. This study reveals for the first time the correlation between EVs-mediated miRNA in feline peripheral blood and IFN-ω on antiviral immune response, which may provide strong data support for the development of novel antiviral nanomedicine and the research of the antiviral effects of IFN-ω.


Asunto(s)
Vesículas Extracelulares , Interferón Tipo I , MicroARNs , Gatos , Animales , MicroARNs/genética , Citocinas , Vesículas Extracelulares/metabolismo
5.
BMC Geriatr ; 24(1): 204, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38418958

RESUMEN

BACKGROUND: Frailty is a health condition linked to adverse health outcomes and lower life quality. The PRISMA-7, a 7-item questionnaire from the Program on Research for Integrating Services for the Maintenance of Autonomy (PRISMA), is a validated case-finding tool for frailty with good sensitivity and specificity. This study aimed to translate, culturally adapt, and validate the PRISMA-7 questionnaire for Chinese use. METHODS: A prospective observational study with convenience sampling recruited bilingual adults aged 65 and over living in the community. The Functional Autonomy Measurement System (SMAF) was the gold standard benchmark. The English PRISMA-7 questionnaire was culturally adapted to Chinese using forward and backward translation. Intra- and inter-rater reliability were determined using the intraclass correlation coefficient (ICC). Face, content and criterion validity were determined. The Receiver Operator characteristic (ROC) curve determined the optimal cut-off score. RESULTS: One-hundred-twenty participants (55 females and 65 males) were recruited. The Chinese PRISMA-7 questionnaire had excellent intra-rater and inter-rater reliability (ICC = 1.000). The rigorous forward and backward translation established the face and content validity. The moderately high correlations between the English PRISMA-7 with SMAF (r = - 0.655, p <  0.001) and Chinese PRISMA-7 with SMAF (r = - 0.653, p <  0.001) pairs established the criterion validity. An optimal cut-off score of three "Yes" responses was reported with 100% sensitivity and 85.3% specificity. CONCLUSION: This translation, cross-cultural adaptation, and validation study established the Chinese PRISMA-7 questionnaire. The preliminary results suggest adequate diagnostic test accuracy for frailty screening among the Chinese-literate community.


Asunto(s)
Comparación Transcultural , Fragilidad , Femenino , Humanos , Masculino , China , Fragilidad/diagnóstico , Psicometría/métodos , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Estudios Prospectivos
6.
Medicine (Baltimore) ; 102(51): e36591, 2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38134118

RESUMEN

RATIONALE: Crizotinib has been approved in many countries for the treatment of patients with advanced ROS1-rearranged non-small cell lung cancers (NSCLC). Entrectinib is a ROS1 inhibitor that has been designed to effectively penetrate and remain in the central nervous system (CNS) and has been recommended as first-line therapy. Few reports have precisely described sequential crizotinb followed by entrectinib in patients with ROS1 fusion in later settings. PATIENT CONCERNS: A 56-year-old man with a history of occasional smoking visited our hospital with cough, sputum, and shortness of breath. DIAGNOSIS: He was diagnosed with right lung adenocarcinoma (T4N2M1a, stage IV) after image and histological examination, without EGFR or ALK fusion mutation. INTERVENTIONS: He received three prior lines of therapies, including chemotherapy, nivolumab monotherapy, and paclitaxel plus anlotinib, with progression-free survival (PFS) of 5, 2, and 11.5 months, respectively. Then the patient began to have headaches and dizziness, and brain magnetic resonance imaging showed multiple brain metastases. Next-generation sequencing (NGS) of the biopsy from neck lymph node identified EZR-ROS1 (1.25% abundance). After 2 months of crizotinib (250 mg daily) plus bevacizumab, all pulmonary and brain lesions decreased, but a small liver lesion was discovered. As treatment went on for another 4 months, the liver lesion continued to grow while other lesions kept decreased or stable state. NGS analysis on the peripheral blood found the disappearance of EZR-ROS1 fusion and a new NTRK2 mutation (c.5C>T, p.Ser2Leu, 0.34% abundance) without other targetable molecular alteration. He received entrectinib (600 mg daily) plus bevacizumab and achieved a partial response. After 7 months of therapy, examination revealed progression of brain lesions. OUTCOMES: The patient had a total PFS of 13 months from sequential crizotinib and entrectinib therapy. LESSONS: A ROS1-rearranged NSCLC with CNS metastases responded to sequential tyrosine kinase inhibitors treatment of crizotinb followed by entrectinib. This report has potential implications in guiding decisions for the treatment after crizotinib resistance.


Asunto(s)
Neoplasias Encefálicas , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Masculino , Persona de Mediana Edad , Bevacizumab/uso terapéutico , Neoplasias Encefálicas/secundario , Carcinoma de Pulmón de Células no Pequeñas/secundario , Crizotinib/uso terapéutico , Neoplasias Pulmonares/patología , Proteínas Tirosina Quinasas , Proteínas Proto-Oncogénicas , Hígado/patología
7.
PLoS One ; 18(9): e0291132, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37669286

RESUMEN

BACKGROUND: The validated Incremental Shuttle Walk Test (ISWT) is widely used for evaluating maximal exercise capacity, with the distance-walked (IWSD) as the primary outcome. However, there are no normative reference values (NRV) and reference equations to predict ISWD for the Singaporean population. OBJECTIVES: This study aims to establish the NRV and reference equations for ISWD in healthy Singaporeans aged 21 to 80 and investigate the determining variables during ISWT. METHODS: This cross-sectional study recruited community-dwelling healthy subjects aged 21-80 from the community via convenience sampling. Each subject completed two trials of the ISWT according to the standard protocol. Variables measured during the trials included ISWD, pre-and post-test heart rate (HR), oxygen saturation, blood pressure (BP), modified Borg's dyspnoea score and Borg's rate of perceived exertion (RPE). RESULTS: 199 healthy Singaporean (females = 114, males = 85) participated in the study. The overall median ISWD was 660.0 metres (m) [interquartile range (IQR):440.0-850.0]. The age-stratified mean ISWD ranged from 430.0 m (IQR:350.0-450.0) (aged 60-80) to 480.0 m (IQR:438.0-650.0) (aged 40-59) to 780.0 m (IQR:670.0-960.0) (aged 21-39). Gender, age, weight, height and HR change (highest post-test HR minus pre-test HR) were the most significant variables (p < 0.001). IWSD (m) = 651.4(Height, m) +89.7(Gender, male = 1; female = 0) -6.31(Age, years) -3.61(Weight, kilograms) +2.54(HR change, beats per minute); R2 = 0.741. Previously published ISWT reference equations cannot accurately predict the ISWD in the Singaporean population. CONCLUSIONS: This study investigated the ISWD NRV and established reference equations for healthy Singaporeans aged 21-80. The information would be beneficial in setting performance benchmarks to guide physical assessment, intervention and rehabilitation.


Asunto(s)
Asiático , Prueba de Paso , Femenino , Humanos , Masculino , Estudios Transversales , Frecuencia Cardíaca , Valores de Referencia , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años
8.
Front Microbiol ; 14: 1158659, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37649630

RESUMEN

Extended-spectrum beta-lactamase-producing Gram-negative bacteria are common in the community and hospitals. To monitor ESBLs mediated by the CTX-M genotype, we collected clinical ESBL pathogenic strains from a hospital in central China and observed a strain of Escherichia coli, namely Ec15103 carrying blaCTX-M-14, blaCTX-M-64 and blaTEM-1, isolated from the blood of a 7-day-old infant in 2015. Strain Ec15103 contains two drug resistance plasmids: pEc15103A, an IncFI-type plasmid that cannot be conjugatively transferred and carries the drug resistance genes blaTEM-1, aacC2, aadA5, sul1, mph(A), sul2, strAB, and tetA(A); and pEc15103B, an IncK2/Z-type plasmid that carries the conjugation transfer gene and blaCTX-M-14. In addition, blaCTX-M-64 is located on the chromosome of Ec15103, and it is the first report of pathogen with blaCTX-M-64 located on its chromosome (the search terms used "blaCTX-M-64" and "chromosome"). blaCTX-M-14 and blaCTX-M-64 are carried by ISEcp1-mediated transposon Tn6503a and Tn6502, respectively. The conjugation transfer ability of pEc15103B was significantly inhibited by zidovudine (AZT) and linoleic acid (LA) and that expression of blaCTX-M-14, blaCTX-M-64 and blaTEM-1 at the mRNA level did not change based on the concentration of cefotaxime or ampicillin. Co-occurrence of blaCTX-M-14 and blaCTX-M-64 in a single isolate will enhance the drug resistance of bacteria, and the presence of blaCTX-M-64 in the chromosome may make the resistance more maintain. This fact will facilitate its dissemination and persistence under different antimicrobial selection pressures. It is essential to prevent these strains from further spreading in a hospital environment.

9.
Front Cell Dev Biol ; 11: 1176083, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37389354

RESUMEN

Advanced non-small cell lung cancer (NSCLC) with MET amplification primarily relies on MET inhibitors for treatment, but once resistance occurs, the available treatment options are limited and the prognosis is typically poor. A 57-year-old man with advanced NSCLC and C-MET amplification was initially treated with crizotinib but developed progressive disease. After the antirotinib treatment, he achieved a partial response for a year. Genetic testing showed high PD-L1 expression, and he was treated with pembrolizumab and chemotherapy for 3 months, with partial response. Maintenance therapy with pembrolizumab and local I-125 seeds brachytherapy (ISB) was given after the lung lesion progressed but other lesions remained stable. The therapy resulted in significant resolution of the right upper lung lesion. It demonstrates the effectiveness of ISB-ICI combination in treating MET amplification advanced NSCLC. Ongoing research and treatment innovation are important in managing advanced NSCLC with complex genetic aberrations. To explore the candidate mechanism of ISB therapy response, we download public genetic data and conduct different expression Lncrnas analysis and pathway analysis to discover radiotherapy related sensitive or resistance lncRNAs and pathways, we found that AL654754.1 is a key lncRNA with radiotherapy response, and it also include in classical p53 and Wnt signaling pathway. Overall, the clinical case reports, combined with the exploration of underlying mechanisms, provide positive guidance for the precise treatment of lung cancer.

10.
Artículo en Inglés | MEDLINE | ID: mdl-37174230

RESUMEN

The "Timed-Up-and-Go" test (TUG) is a standard assessment tool for functional mobility as it assesses several functional components, including balance, gait, and lower-extremity strength. It has good reliability and validity and is cost-effective and safe, making it an ideal screening tool for falls in various populations, such as older adults or various conditions. However, TUG interpretation relies on comparisons against local normative reference values (NRV), which few studies established for the Asian or younger population. Hence, this study aims to: (1) establish the normative reference values NRV for the population aged 21 to 85 years; (2) determine demographic and anthropometric variables that influence the TUG results; and (3) establish the regression equation of the TUG. A prospective, convenience sampling cross-sectional study recruited subjects aged 21-85 from the community to complete two TUG trials in various parts of Singapore. Variables collected include gender, age, height (meters, m), weight (kilograms, kg), and hand grip strength (HGS) (kg). The intraclass correlation coefficient (ICC) and 95% confidence interval (95% CI) determined test-retest, intra- and inter-rater reliabilities. TUG and variables were analyzed with descriptive statistics and multiple linear regression. p < 0.05 was accepted as statistical significance. Further, 838 subjects (542 females, 296 males) completed the data collection. The mean TUG time was 9.16 s (95% CI 9.01-9.3). Slower TUG was observed with advanced age and female gender. Multiple linear regression analysis demonstrated that age, height, and weight were the best variables to predict TUG scores. The regression formula presented as: TUG (second) = 9.11 + 0.063 (Age, years)-3.19 (Height, meters) + 0.026 (Weight, Kilograms) (R2 = 0.374, p < 0.001). This study provided the TUG NRV and regression formula for healthy Asian adults aged 21 to 85. The information may provide a quick reference for the physical function to interpret assessment findings and guide decision-making in various health and healthcare settings.


Asunto(s)
Fuerza de la Mano , Equilibrio Postural , Masculino , Humanos , Femenino , Anciano , Estudios Prospectivos , Valores de Referencia , Estudios Transversales , Reproducibilidad de los Resultados
11.
bioRxiv ; 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37214924

RESUMEN

We investigated the lateralization of gut-innervating vagal sensory neurons and their roles in feeding behavior. Using genetic, anatomical, and behavioral analyses, we discovered a subset of highly lateralized vagal sensory neurons with distinct sensory responses to intestinal stimuli. Our results demonstrated that left vagal sensory neurons (LNG) are crucial for distension-induced satiety, while right vagal sensory neurons (RNG) mediate preference for nutritive foods. Furthermore, these lateralized neurons engage different central circuits, with LNG neurons recruiting brain regions associated with energy balance and RNG neurons activating areas related to salience, memory, and reward. Altogether, our findings unveil the diverse roles of asymmetrical gut-vagal-brain circuits in feeding behavior, offering new insights for potential therapeutic interventions targeting vagal nerve stimulation in metabolic and neuropsychiatric diseases.

12.
Artículo en Inglés | MEDLINE | ID: mdl-36673801

RESUMEN

Since the Industrial Revolution, the impacts of human activities have changed the global climate system, and climate warming has had rapid and widespread effects on the planet. At present, the world is experiencing a series of natural disasters, such as climate change, environmental pollution, biodiversity loss, and sea level rise, which pose a serious threat to the livability of the Earth. An international consensus has been reached that achieving carbon neutrality is the key to tackling climate change; it is also crucial to building a livable planet. To achieve carbon neutrality, energy is the main aspect, for which technology regarding resources and the environment is essential. In this context, we collected data, performed an in-depth analysis of the basic and structural characteristics of the development of the coal industry and environmental remediation, studied and judged the trends in regional economic development and demand growth, and closely examined the requirements of China's development strategy, which focuses on the ideas of carbon peak and carbon neutralization in line with local development trends and economic system characteristics. We must build a livable Earth, promote the green and low-carbon transformation of regional energy, promote high-quality economic development, and ensure the safe supply of energy.


Asunto(s)
Carbono , Restauración y Remediación Ambiental , Humanos , Contaminación Ambiental , China , Desarrollo Económico , Dióxido de Carbono
13.
BMC Pulm Med ; 23(1): 4, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36604675

RESUMEN

BACKGROUND: Observational studies reported an association between psoriasis and risk of lung cancer. However, whether psoriasis is causally associated with lung cancer is unclear. METHODS: Genetic summary data of psoriasis were retrieved from two independent genome-wide association studies (GWAS). Genetic information of lung cancer was retrieved from GWAS of International Lung Cancer Consortium. A set of quality control steps were conducted to select instrumental tools. We performed two independent two-sample Mendelian randomization (MR) analyses and a meta-analysis based on the two independent MR estimates to assess the causal relationship between psoriasis and lung cancer (LUCA) as well as its subtypes, squamous cell carcinoma (LUSC) and adenocarcinoma (LUAD). RESULTS: Between-SNP heterogeneity was present for most MR analyses, whereas horizontal pleiotropy was not detected for all MR analyses. Multiplicative random-effect inverse variance weighted (IVW-MRE) method was therefore selected as the primary MR approach. Both IVW-MRE estimates from the two independent MR analyses suggested that there was no significant causal relationship between psoriasis and LUCA as well as its histological subtypes. Sensitivity analyses using other four MR methods gave similar results. Meta-analysis of the two IVW-MRE derived MR estimates yielded an odds ratio (OR) of 1.00 (95% CI 0.95-1.06) for LUCA, 1.01 (95% CI 0.93-1.08) for LUSC, and 0.97 (95% CI 0.90-1.06) for LUAD. CONCLUSION: Our results do not support a genetic association between psoriasis and lung cancer and its subtypes. More population-based and experimental studies are warranted to further dissect the complex correlation between psoriasis and lung cancer.


Asunto(s)
Neoplasias Pulmonares , Psoriasis , Humanos , Análisis de la Aleatorización Mendeliana , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/genética , Psoriasis/epidemiología , Psoriasis/genética
14.
Front Genet ; 13: 968376, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36506325

RESUMEN

Background: Previous studies have suggested that patients with lung adenocarcinoma (LUAD) will significantly benefit from epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI). However, many LUAD patients will develop resistance to EGFR-TKI. Thus, our study aims to develop models to predict EGFR-TKI resistance and the LUAD prognosis. Methods: Two Gene Expression Omnibus (GEO) datasets (GSE31625 and GSE34228) were used as the discovery datasets to find the common differentially expressed genes (DEGs) in EGFR-TKI resistant LUAD profiles. The association of these common DEGs with LUAD prognosis was investigated in The Cancer Genome Atlas (TCGA) database. Moreover, we constructed the risk score for prognosis prediction of LUAD by LASSO analysis. The performance of the risk score for predicting LUAD prognosis was calculated using an independent dataset (GSE37745). A random forest model by risk score genes was trained in the training dataset, and the diagnostic ability for distinguishing sensitive and EGFR-TKI resistant samples was validated in the internal testing dataset and external testing datasets (GSE122005, GSE80344, and GSE123066). Results: From the discovery datasets, 267 common upregulated genes and 374 common downregulated genes were identified. Among these common DEGs, there were 59 genes negatively associated with prognosis, while 21 genes exhibited positive correlations with prognosis. Eight genes (ABCC2, ARL2BP, DKK1, FUT1, LRFN4, PYGL, SMNDC1, and SNAI2) were selected to construct the risk score signature. In both the discovery and independent validation datasets, LUAD patients with the higher risk score had a poorer prognosis. The nomogram based on risk score showed good performance in prognosis prediction with a C-index of 0.77. The expression levels of ABCC2, ARL2BP, DKK1, LRFN4, PYGL, SMNDC1, and SNAI2 were positively related to the resistance of EGFR-TKI. However, the expression level of FUT1 was favorably correlated with EGFR-TKI responsiveness. The RF model worked wonderfully for distinguishing sensitive and resistant EGFR-TKI samples in the internal and external testing datasets, with predictive area under the curves (AUC) of 0.973 and 0.817, respectively. Conclusion: Our investigation revealed eight genes associated with EGFR-TKI resistance and provided models for EGFR-TKI resistance and prognosis prediction in LUAD patients.

15.
Dalton Trans ; 51(45): 17481-17487, 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36331374

RESUMEN

In this work, four different bis(imidazole) ligands, namely 1,4-bis(1-imidazolyl)benzene (bib), 4,4'-bis(1-imidazolyl)biphenyl (bibp), 1,4-bis (imidazol-1-ylmethylene)benzene) (bimb) and 4,4'-bis(imidazol-1-yl)diphenyl ether (bidpe), were used as the second ligand to give rise to the structural diversity of a coordination polymer based on the cobalt-miipa (H2miipa = 5-(2-methylimidazol-1-yl) isophthalic acid) system. In compound 1, miipa2- coordinates to Co(II) atoms to form the Co-miipa 3D network. On introducing linear bis(imidazole) ligands with different lengths and rigidities into the Co(II)-miipa system, the obtained compounds 2-4 form similar three-fold interpenetrating 3D MOFs constructed from the Co(II)-miipa layers pillared by bis(imidazole) ligands. While introducing the V-shaped half-flexible bis(imidazole) ligands, the obtained compound 5 exhibits a 2D double-layered network built from the Co(II)-miipa 1D quadrangular prism linked by the bis(imidazole) ligand. Each 2D double layer is further interlocked with two neighboring ones to produce an interesting 3D framework. Significantly, CoNC-5 derived from a mixture of dicyandiamide (DCD) and compound 5 with a low void volume shows a superior electrocatalytic performance for the oxygen reduction reaction. The Eonset (0.974 V) and E1/2 (0.830 V) of CoNC-5 in O2-saturated 0.1 M KOH at 1600 rpm and 5 mV s-1 are superior to those of Pt/C (0.968 and 0.799 V). The JL value of CoNC-5 (JL = 5.29 mA cm-2) is higher than that of Pt/C (5.09 mA cm-2).

16.
Artículo en Inglés | MEDLINE | ID: mdl-36430111

RESUMEN

The molecular composition of the lipid biomarkers in the surface water, water column, and surface sediments collected along the Pearl River was investigated to identify the mechanisms of the delivery and preservation of autochthonous organic carbon (AOC) and to estimate its contribution to the carbon sink. The spatial distribution of these lipid biomarkers showed that samples collected at high-DIC-concentration sites (DIC: dissolved inorganic carbon) had prominent aquatic autochthonous signatures, while samples collected at low-DIC-concentration sites showed greater terrestrial contributions, which were described as the DIC fertilization effects. In the summer, typically, intense precipitation and flood erosion diluted the biogeochemical composition and carried terrestrial plant detritus. Therefore, the percentage of AOC (auto%) was higher in the winter than in the summer. According to the calculation of the lipid biomarkers, the values of the auto% were 65% (winter) and 54% (summer) in the surface water, 55.9% (winter) and 44.6% (summer) in the below-surface water, and 52.1% (winter) and 43.9% (summer) in the surface sediment, which demonstrated that AOC accounted for a major portion of the TOC. Vertical variability was mainly present in sites with intense flood erosion, which resulted in the mixing and deposition of resuspended sediments. There was a positive correlation of the clay content with the auto% value and the biogeochemical composition, showing that clay adsorbed the organic carbon in the water, vertically deposited it into the sediment, and was the dominant mechanism of the vertical delivery of organic carbon (OC). According to the new karst carbon sink model, based on coupled carbonate weathering and aquatic photosynthesis, the karst carbon sink flux (CSF) in the Pearl River was 2.69 × 106 t/a which was 1.7 times the original estimation (1.58 × 106 t/a), and this did not consider the formation of AOC. This indicated that previously, the contribution of the riverine system to the global karst carbon sink may have been highly underestimated.


Asunto(s)
Secuestro de Carbono , Ríos , Ríos/química , Carbono/análisis , Agua , Arcilla , Monitoreo del Ambiente , Biomarcadores , Lípidos
17.
Artículo en Inglés | MEDLINE | ID: mdl-36360986

RESUMEN

On 15 March 2021, Chinese President Xi Jinping pointed out that "achieving carbon peak and carbon neutrality is a broad and profound economic and social systemic change" and called for "putting energy and resources conservation in the first place". Natural resources are the material basis, space carrier and energy source of high-quality development. The source of carbon emissions is resource utilization, and carbon reduction and removal also depend on resources. The improvement of carbon sink capacity is inseparable from natural resources. To achieve the goal of "double carbon", it is necessary to consolidate the carbon sink capacity of the ecosystem, as well as enhancing its carbon sink increment. Among natural resources, forest carbon sinks, soil carbon sinks and karst carbon sinks have significant emission reduction potential and cost advantages, representing important means to deal with climate change. This paper reviews the relevant research results at home and abroad, summarizes the carbon sink estimation, carbon sink potential, carbon sink influencing factors, ecological compensation mechanism and other aspects, analyzes the path selection of establishing carbon sink green development, and puts forward corresponding policies and suggestions, providing a theoretical reference for the achievement of the carbon neutrality goal in the field of natural resources in China.


Asunto(s)
Carbono , Ecosistema , Carbono/análisis , Desarrollo Sostenible , Conservación de los Recursos Naturales , Secuestro de Carbono , Recursos Naturales , China
18.
Dalton Trans ; 51(12): 4862-4868, 2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35258057

RESUMEN

The urothermal reactions of Co(II)/Zn(II) salts with the diverse carboxylic acid and 1,3,5,-tris(1-imidazolyl)benzene(tib) ligands afforded three novel MOFs, namely, [Co3(tib)2(abdc)2(ox)]2·6H2O (1), [Co3O(tib)(abdc)2(DMI)]·2DMI·2H2O (2) and [Zn3I2(tib)2(napdc)2]·2DMI·2H2O (3), (H2abdc = 5-amino-1,3-benzenedicarboxylate, H2napdc = 1,4-naphthalene dicarboxylic acid and DMI = 1,3-dimethyl-2-imidazolidinone). In compounds 1 and 2, the Co(II) atoms are connected by polycarboxylate ligands to form two-dimensional (2D) layers that are pillared by tib ligands leading to the formation of 3D porous frameworks. In compound 3, the Zn(II) atoms are linked by tib ligands to form one-dimensional ribbon-like chains which are further connected by polycarboxylate ligands, making a 3D framework possible. Compound 1 can selectively adsorb unsaturated hydrocarbon molecules (C2H2 and C2H4) and saturated hydrocarbon molecules (C2H6 and CH4). Specifically, compound 1 has high IAST selectivity for acetylene and methane (0.50 : 0.50, v/v) at 273 K and 1 bar. DFT calculations reveal that the π-conjugated hexagonal carbon ring may be the primary adsorption site because there are π-π interactions between the unsaturated hydrocarbon molecules (C2H2 and C2H4) and the π-conjugated hexagonal carbon ring in the framework of compound 1.

19.
Sci Total Environ ; 812: 152429, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34952062

RESUMEN

Autochthonous organic carbon (AOC) formed by biological carbon pump (BCP) in surface waters may serve as a significant carbon sink. The locations, magnitudes, variations and mechanisms responsible for the terrestrial missing carbon sink by BCP are uncertain, especially in large river systems. In this study, hydrochemical characteristics, carbon isotope compositions of dissolved inorganic carbon (DIC) and organic carbon (OC), n-alkane homologues and C/N ratios of organic matter along the Yangtze River and the Yellow River were investigated to constrain the OC source and the significance of BCP effect. It was found that (1) DIC concentrations in the Yellow River were much higher than those in the Yangtze River, which was controlled primarily by the temperature effect; (2) AOC in the both rivers was characterized by lower C/N ratios and δ13CPOC values. Based on calculation of n-alkanes compounds, the AOC proportions ranged from 29 to 88% (49% on average, with a higher proportion (55%) in the rainy season than in the dry season (46%)) and 19-68% (41% on average; with a lower proportion in the rainy season (31%) than in the dry season (51%)) in the Yangtze River and the Yellow River, respectively, indicating intense aquatic production. Low dissolved CO2 concentration (6.17 µmol/L on average) of the Yangtze River limited the aquatic production and decreased the BCP effect in the dry season, indicated by lower AOC proportion. However, the BCP effect increased in the Yellow River in the dry season mainly due to the increased light penetration; (3) even in high turbidity riverine systems such as the Yellow River, the aquatic photosynthetic uptake of DIC could produce considerable AOC. These findings clearly show the formation of AOC by BCP in both the clear and high turbidity riverine systems, suggesting a potential direction for finding the terrestrial missing carbon sink.


Asunto(s)
Carbono , Ríos , Biomarcadores , Carbono/análisis , Isótopos de Carbono/análisis , China , Monitoreo del Ambiente , Lípidos , Proteínas de Transporte de Membrana
20.
Front Microbiol ; 12: 664926, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34295316

RESUMEN

Mitogen-activated protein kinase (MAPK) pathways play a vital role in multiple plant processes, including growth, development, and stress signaling, but their involvement in response to Ralstonia solanacearum is poorly understood, particularly in pepper plants. Herein, CaMAPK7 was identified from the pepper genome and functionally analyzed. The accumulations of CaMAPK7 transcripts and promoter activities were both significantly induced in response to R. solanacearum strain FJC100301 infection, and exogenously applied phytohormones, including methyl jasmonate (MeJA), brassinolide (BR), salicylic acid (SA), and ethephon (ETN), were decreased by abscisic acid (ABA) treatment. Virus-induced gene silencing (VIGS) of CaMAPK7 significantly enhanced the susceptibility of pepper plants to infection by R. solanacearum and downregulated the defense-related marker genes, including CaDEF1, CaPO2, CaSAR82A, and CaWRKY40. In contrast, the ectopic overexpression of CaMAPK7 in transgenic tobacco enhanced resistance to R. solanacearum and upregulated the defense-associated marker genes, including NtHSR201, NtHSR203, NtPR4, PR1a/c, NtPR1b, NtCAT1, and NtACC. Furthermore, transient overexpression of CaMAPK7 in pepper leaves triggered intensive hypersensitive response (HR)-like cell death, H2O2 accumulation, and enriched CaWRKY40 at the promoters of its target genes and drove their transcript accumulations, including CaDEF1, CaPO2, and CaSAR82A. Taken together, these data indicate that R. solanacearum infection induced the expression of CaMAPK7, which indirectly modifies the binding of CaWRKY40 to its downstream targets, including CaDEF1, CaPO2, and CaSAR82A, ultimately leading to the activation of pepper immunity against R. solanacearum. The protein that responds to CaMAPK7 in pepper plants should be isolated in the future to build a signaling bridge between CaMAPK7 and CaWRKY40.

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