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1.
ACS Omega ; 9(12): 14174-14186, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38559910

RESUMO

Coal gangue spontaneous combustion has caused serious environmental and ecological problems. To investigate the reaction kinetic parameters of the gangue and the exothermic characteristics of the spontaneous combustion of the influence of the law, this study employs the thermogravimetric method to explore the characteristic parameters of the pyrolysis and oxidative combustion process of the gangue from the perspective of thermodynamics, and, at the same time, using the differential scanning calorimetry (DSC) on the exothermic effect of the gangue to explore the gangue to obtain the gangue and the original coal TG/DTG/DSC curves to be compared and from the perspective of thermodynamics. The change rule and potential parameters in the pyrolysis and oxidative combustion process of coal gangue (CG) were analyzed, the oxidation kinetic properties of CG were studied, and the reaction mechanism of oxidative spontaneous combustion of CG was further explained. The results show that the TG/DTG/DSC curves of CG in different gas atmospheres will have significant differences in all stages, and in the process of pyrolysis and oxidative combustion, the thermogravimetric curves of CG and those of the original coal show a consistent trend, except for the large difference in peak amplitude in different stages; in different gas atmospheres, as the rate of warming increases, the TG/DTG/DSC curves of the gangue are tilted toward the high-temperature region, they are inclined to the high-temperature region with the increase of the heating rate, and the phenomenon of "hysteresis" of characteristic temperature occurs. The research results provide a theoretical basis for the construction of a spontaneous combustion early warning system based on the fine division of gangue pyrolysis and oxidation combustion stages.

2.
Ecol Evol ; 14(4): e11225, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38584774

RESUMO

A new species of Papaveraceae, Corydalis sunhangii, in the section Trachycarpae, is described and illustrated from Nyingchi City, Xizang, China. The new species has some resemblance to Corydalis kingdonis, but differs by radical leaves prominent, usually several, blade tripinnate (vs. insignificant, few, blade bi- to triternate); cauline leaf usually one, much smaller than radical leaves, usually situated in lower half of stem (vs. usually two, larger than radical leaves, concentrated in upper third of stem); racemes densely 13-35-flowered (vs. rather lax, 4-11-flowered); claw of lower petal shallowly saccate (vs. very prominently and deeply saccate); capsule oblong, with raised lines of dense papillae (vs. broadly obovoid, smooth). Phylogenetic analysis, based on 68 protein-coding plastid genes of 49 samples, shows that C. sunhangii is not closely related to any hitherto described species, which is consistent with our morphological analysis.

3.
Oncol Lett ; 27(5): 224, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38586212

RESUMO

Anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) have transformed the treatment paradigm for patients with ALK-positive non-small cell lung cancer (NSCLC). Yet the differential efficacy between alectinib and crizotinib in treating patients with NSCLC and central nervous system (CNS) metastases has been insufficiently studied. A retrospective analysis was conducted of clinical outcomes of patients with ALK-positive NSCLC and CNS metastases treated at the Shandong Cancer Centre. Based on their initial ALK-TKI treatment, patients were categorised into either the crizotinib group or the alectinib group. Efficacy, progression-free survival (PFS), intracranial PFS and overall survival (OS) were evaluated. A total of 46 eligible patients were enrolled in the present study: 33 patients received crizotinib and 13 patients received alectinib. The median OS of the entire group was 66.8 months (95% CI: 48.5-85.1). Compared with the patients in the crizotinib group, the patients in the alectinib group showed a significant improvement in both median (m)PFS (27.5 vs. 9.5 months; P=0.003) and intracranial mPFS (36.0 vs. 10.8 months; P<0.001). However, there was no significant difference in OS between the alectinib and crizotinib groups (not reached vs. 58.7 months; P=0.149). Furthermore, there were no significant differences between patients receiving TKI combined with radiotherapy (RT) vs. TKI alone with respect to mPFS (11.0 vs. 11.7 months, P=0.863) as well as intracranial mPFS (12.5 vs. 16.9 months, P=0.721). In the present study, alectinib exhibited superior efficacy to crizotinib for treating patients with ALK-positive NSCLC and CNS metastases, especially in terms of delaying disease progression and preventing CNS recurrence. Moreover, the results demonstrated that it might be beneficial to delay local RT for patients with ALK-positive NSCL and CNS metastases.

4.
Int Wound J ; 21(4): e14847, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38584331

RESUMO

Due to the high risks of postoperative complications brought on by gastric cancer, traditional Chinese medicine (TCM) as a commonly used therapy, has exerted its vital role in postoperative recovery care. In this sense, this meta-analysis was conducted to explore the related documents about TCM's impact on gastric cancer postoperative recovery. During the research, we explored a total of 1549 results from databases PubMed, China National Knowledge Infrastructure (CNKI), Embase, Cochrane Library and Web of Science (WoS). Thirty-two clinical randomized trials (RCTs) were then selected and analysed for this meta-analysis by using the software RevMan 5.4 (under PRISMA 2020 regulations), with a population of 3178 patients. Data prove that TCM therapy reduced the risks for postoperative complications exposure by an estimated average of 19% (95% CI). Among the complications, TCM therapy suppressed the risks of wound infection and incisional infections by 53% and 48% respectively. Meanwhile, the patient's wound healing duration exhibited a significant reduction compared to those without TCM treatment, with a difference at around 0.74 days (95% CI). TCM also exerted its potential to strengthen the patient's immune and health conditions, leading to a significantly promoted gastrointestinal function in the patients with a shorter duration to release first exhaustion and defecation compared to those with no TCM therapy. In addition, similar promoted phenomena also exist in those patients with TCM therapy in terms of their immunity and nutritional conditions. These facts all indicate a positive impact of TCM therapy in clinical applications.


Assuntos
Medicamentos de Ervas Chinesas , Complicações Pós-Operatórias , Neoplasias Gástricas , Humanos , China , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/métodos , Complicações Pós-Operatórias/terapia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia
6.
BMC Womens Health ; 24(1): 215, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570811

RESUMO

BACKGROUND: More than 2 billion women are experiencing the menopausal transition in China, and some of these women have hypertension. Limited studies has focused on perimenopausal syndrome and hypertension in a specific population, so we aimed to investigate the prevalence of perimenopausal syndrome and hypertension and to analyse their relationships and risk factors in perimenopausal women in South China. METHODS: This cross-sectional study included 3553 women aged 40 to 60 years from South China. We collected medical report, lifestyle, blood sample, general condition questionnaire, and modified Kupperman index (mKMI) data. Multivariate logistic regression analysis was performed to identify risk factors for perimenopausal syndrome and hypertension during perimenopause. RESULTS: The prevalence of hypertension in perimenopause patients was 16.58%, and the prevalence of perimenopausal syndrome was 9.9%. Compared with women without hypertension during perimenopause, women with HTN during perimenopause had an increased risk of perimenopausal syndrome (26.4% vs. 8.7%, P < 0.001). Lipid levels and urinary tract infections were risk factors for hypertension and perimenopausal syndrome, in addition to the presence of breast nodules, the intake of snacks at night, high-salt diets, red meat and sugar-sweetened beverages, and a history of smoking and drinking for perimenopausal syndrome and the presence of gestational hypertension and diabetes for hypertension. CONCLUSION: We concluded that perimenopausal syndrome and HTN are common in perimenopausal women in South China, and the associations between them are strong and positive. Perimenopausal syndrome shares some common risk factors with HTN during perimenopause, such as BMI and dyslipidaemia. Therefore, gynaecological endocrinologists in China should consider screening for perimenopausal syndrome in hypertensive perimenopausal women, and appropriate management of perimenopause is needed to alleviate these conditions.


Assuntos
Hipertensão , Perimenopausa , Feminino , Humanos , Prevalência , Estudos Transversais , Fatores de Risco , Hipertensão/epidemiologia , China/epidemiologia
7.
Mol Biol Rep ; 51(1): 484, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578353

RESUMO

BACKGROUND: Mitochondrial Ts translation elongation factor (TSFM) is an enzyme that catalyzes exchange of guanine nucleotides. By forming a complex with mitochondrial Tu translation elongation factor (TUFM), TSFM participates in mitochondrial protein translation. We have previously reported that TUFM regulates translation of beta-site APP cleaving enzyme 1 (BACE1) via ROS (reactive oxygen species)-dependent mechanism, suggesting a potential role in amyloid precursor protein (APP) processing associated with Alzheimer's disease (AD), which led to the speculation that TSFM may regulate APP processing in a similar way to TUFM. METHODS AND RESULTS: Here, we report that in cultured cells, knockdown or overexpression TSFM did not change protein levels in BACE1 and APP. Besides, the levels of cytoplasmic ROS and mitochondrial superoxide, in addition to ATP level, cell viability and mitochondrial membrane potential were not significantly altered by TSFM knockdown in the short term. Further transcriptome analysis revealed that expression of majority of mitochondrial genes were not remarkably changed by TSFM silencing. The possibility of TSFM involved in cardiomyopathy and cancer development was uncovered using bioinformatics analysis. CONCLUSIONS: Collectively, short-term regulation of TSFM level in cultured cells does not cause a significant change in proteins involved in APP processing, levels in ROS and ATP associated with mitochondrial function. Whereas our study could contribute to comprehend certain clinical features of TSFM mutations, the roles of TSFM in cardiomyopathy and cancer development might deserve further investigation.


Assuntos
Doença de Alzheimer , Cardiomiopatias , Neoplasias , Humanos , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Aspártico Endopeptidases/genética , Doença de Alzheimer/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Cardiomiopatias/metabolismo , Fatores de Alongamento de Peptídeos/metabolismo , Trifosfato de Adenosina , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo
8.
Ther Adv Neurol Disord ; 17: 17562864241239117, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38616782

RESUMO

Multiple sclerosis (MS) was defined as a rare disease in China due to its low prevalence. For a long time, interferon ß was the only approved disease-modifying therapy (DMT). Since the first oral DMT was approved in 2018, DMT approval accelerated, and seven DMTs were approved within 5 years. With an increasing number of DMTs being prescribed in clinical practice, it is necessary to discuss the standardized MS treatment algorithms depending on the disease activity and DMT availability. In this review paper, more than 20 Chinese experts in MS have reviewed the therapeutic progress of MS in China and worldwide and discussed algorithms for treating relapsing MS (RMS) based on the available DMTs in China, providing insights for establishing the standardized RMS treatment algorithms in this country.


Treatment algorithms of relapsing multiple sclerosis in China In this review paper, more than 20 Chinese experts in MS have reviewed the therapeutic progress of MS in China and worldwide and discussed algorithms for treating relapsing MS (RMS) based on the available DMTs in China, providing insights for establishing the standardized RMS treatment algorithms in this country: 1) CIS and RRMS account for more than 90% of the MS patients and most of them are mild to moderate; 2) MS patients should initiate DMT treatments as soon as the disease has been diagnosed in order to reduce the risk of disease progression; 3) Patients who have been diagnosed with MS should start treatment with fundamental DMTs unless the disease course has been highly active; 4) MAGNIMS score may be a suitable and simplified assessment tool for measuring treatment response to DMTs; 5) Patients treated with corticosteroids and NSIS should be switched to the standardized DMT treatment during remission in accordance with disease activity.

9.
J Med Chem ; 67(8): 6822-6838, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38588468

RESUMO

Weak antigens represented by MUC1 are poorly immunogenic, which greatly constrains the development of relevant vaccines. Herein, we developed a multifunctional lipidated protein as a carrier, in which the TLR1/2 agonist Pam3CSK4 was conjugated to the N-terminus of MUC1-loaded carrier protein BSA through pyridoxal 5'-phosphate-mediated transamination reaction. The resulting Pam3CSK4-BSA-MUC1 conjugate was subsequently incorporated into liposomes, which biomimics the membrane structure of tumor cells. The results indicated that this lipidated protein carrier significantly enhanced antigen uptake by APCs and obviously augmented the retention of the vaccine at the injection site. Compared with the BSA-MUC1 and BSA-MUC1 + Pam3CSK4 groups, Pam3CSK4-BSA-MUC1 evoked 22- and 11-fold increases in MUC1-specific IgG titers. Importantly, Pam3CSK4-BSA-MUC1 elicited robust cellular immunity and significantly inhibited tumor growth. This is the first time that lipidated protein was constructed to enhance antigen immunogenicity, and this universal carrier platform exhibits promise for utilization in various vaccines, holding the potential for further clinical application.


Assuntos
Lipossomos , Mucina-1 , Animais , Mucina-1/imunologia , Mucina-1/química , Camundongos , Humanos , Lipopeptídeos/química , Lipopeptídeos/imunologia , Lipopeptídeos/farmacologia , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/química , Soroalbumina Bovina/química , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/química , Feminino , Camundongos Endogâmicos BALB C , Antígenos/imunologia , Linhagem Celular Tumoral
10.
Transl Oncol ; 44: 101953, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593585

RESUMO

BACKGROUND: Fibronectin type III domain containing 1 (FNDC1) has been associated with the metastasis of many tumors, but its function in lung cancer remains uncertain. METHODS: FNDC1 expression was analyzed in The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx), evaluate its prognostic value. Gene Set Enrichment Analysis (GSEA) enrichment analysis of differential expression of FNDC1 in lung cancer. The expression of FNDC1 was detected in five types of lung cancer cells, and screened to establish FNDC1 stable knockdown cell strains. To observe the migration and invasion ability of lung cancer cells after FNDC1 knockdown. Finally, we used rhIL-6 to interfere with the stable knockdown of FNDC1 in A549 cells and observed the recovery of migration and invasion. RESULT: Our results showed that FNDC1 expression was increased in 21 tumor tissues, including lung cancer, and was associated with poor prognosis in five cancers, including lung adenocarcinoma (LUAD) (P < 0.05). GSEA enrichment analysis showed that FNDC1 was related to the pathways involved the JAK-STAT signaling pathway. Stable knockdown of FNDC1 in A549 and H292 cells resulted in decreased migration and invasion ability of both cells, accompanied by decreased expression of MMP-2 and Snail, and a significant decline in the expression of p-JAK2 and p-STAT3. The suppressive effect of FNDC1 knockdown on lung cancer cell metastasis counteracted by the JAK-STAT agonist rhIL-6 were presented in the nude mouse metastatic tumor model. CONCLUSION: FNDC1 is implicated in poor prognosis of a diverse range of malignant tumors, which can promote metastasis and invasion of lung cancer through the JAK2-STAT3 signaling pathway.

11.
Org Lett ; 26(15): 2939-2944, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38602425

RESUMO

A selective three-component 1,2-sulfonyl etherification of aryl 1,3-dienes enabled by copper catalysis to afford biologically interesting alkenyl 1,2-sulfone ether derivatives through C-S and C-O bond formation is described. The protocol proceeds with the sulfonyl chloride and alcohols under simple, mild, and base-free conditions, providing a straightforward route to sulfonylated allyl ether compounds with broad functional group tolerance and excellent chemo- and regioselectivity. Mechanistic studies indicate that the selective alkene difunctionalization includes a key copper-mediated single-electron transfer process.

13.
Chem Commun (Camb) ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619574

RESUMO

Pyrrolo[1,2-a]indoles are structurally important scaffolds in many natural products and bioactive compounds. Herein, we report a novel synthetic method for pyrrolo[1,2-a]indole derivatives through visible-light-induced cascade dearomatizative cyclization of indoles with external nucleophiles. Moderate yields, good diastereoselectivities, and excellent regioselectivities were generally observed with the resultant indole-fused polycyclic compounds.

14.
Food Chem ; 449: 139246, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38604035

RESUMO

The levels of metabolites in honey are influenced by floral origin, production region, and bee species. However, how environmental factors affect honey quality remains unclear. Based on untargeted metabolomics and using UPLC Q-Orbitrap MS, we analyzed 3596 metabolites in 51 honey samples from Yunnan and Shennongjia. Comparative analysis revealed that geniposidic acid, kynurenic acid and caffieine accumulated at significantly different levels between Shennongjia and Yunnan honey. Based on cluster structure analysis, 36 Yunnan honey samples were divided into two distinct groups by altitude. Notably, quercetin, hyperoside, taxifolin, rutin, tryptophan, astragalin and phenylalanine were higher levels in high-altitude honey (>1700 m), whereas abscisic acid was higher levels in low-altitude honey (≤1700 m). Among these, significantly elevated levels of hyperoside, taxfolin, astragalin, and tryptophan were observed in honey collected from high-altitude areas in Shennongjia. Our findings highlight the effect of altitude on honey health-promoting components, providing valuable insights into honey quality.

15.
Plant Physiol Biochem ; 210: 108615, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38631158

RESUMO

Magnesium is one of the essential nutrients for plant growth, and plays a pivotal role in plant development and metabolism. Soil magnesium deficiency is evident in citrus production, which ultimately leads to failure of normal plant growth and development, as well as decreased productivity. Citrus is mainly propagated by grafting, so it is necessary to fully understand the different regulatory mechanisms of rootstock and scion response to magnesium deficiency. Here, we characterized the differences in morphological alterations, physiological metabolism and differential gene expression between trifoliate orange rootstocks and lemon scions under normal and magnesium-deficient conditions, revealing the different responses of rootstocks and scions to magnesium deficiency. The transcriptomic data showed that differentially expressed genes were enriched in 14 and 4 metabolic pathways in leaves and roots, respectively, after magnesium deficiency treatment. And the magnesium transport-related genes MHX and MRS2 may respond to magnesium deficiency stress. In addition, magnesium deficiency may affect plant growth by affecting POD, SOD, and CAT enzyme activity, as well as altering the levels of hormones such as IAA, ABA, GA3, JA, and SA, and the expression of related responsive genes. In conclusion, our research suggests that the leaves of lemon grafted onto trifoliate orange were more significantly affected than the roots under magnesium-deficient conditions, further indicating that the metabolic imbalance of scion lemon leaves was more severe.

16.
Water Res ; 256: 121606, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38631236

RESUMO

Aerobic methanotrophs establish a symbiotic association with denitrifiers to facilitate the process of aerobic methane oxidation coupled with denitrification (AME-D). However, the symbiosis has been frequently observed in hypoxic conditions continuing to pose an enigma. The present study has firstly characterized an electrically induced symbiosis primarily governed by Methylosarcina and Hyphomicrobium for the AME-D process in a hypoxic niche caused by Comammox Nitrospira. The kinetic analysis revealed that Comammox Nitrospira exhibited a higher apparent oxygen affinity compared to Methylosarcina. While the coexistence of comammox and AME-D resulted in an increase in methane oxidation and nitrogen loss rates, from 0.82 ± 0.10 to 1.72 ± 0.09 mmol CH4 d-1 and from 0.59 ± 0.04 to 1.30 ± 0.15 mmol N2 d-1, respectively. Furthermore, the constructed microbial fuel cells demonstrated a pronounced dependence of the biocurrents on AME-D due to oxygen competition, suggesting the involvement of direct interspecies electron transfer in the AME-D process under hypoxic conditions. Metagenomic and metatranscriptomic analysis revealed that Methylosarcina efficiently oxidized methane to formaldehyde, subsequently generating abundant NAD(P)H for nitrate reduction by Hyphomicrobium through the dissimilatory RuMP pathway, leading to CO2 production. This study challenges the conventional understanding of survival mechanism employed by AME-D symbionts, thereby contributing to the characterization responsible for limiting methane emissions and promoting nitrogen removal in hypoxic regions.

17.
J Colloid Interface Sci ; 667: 119-127, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38631250

RESUMO

The current state of drug delivery systems allows for the resolution of specific issues like inadequate solubility, limited targeting capabilities, and complex preparation processes, requiring tailored designs for different drugs. Yet, the major challenge in clinical application lies in surmounting these obstacles with a universal carrier that is effective for a variety of anticancer drugs. Herein, with the help of computer simulation, we rationally design ultrashort peptides GY and CCYRGD, which can co-assemble with hydrophobic anticancer drugs into nanoparticles with enhanced solubility, targeting ability and anticancer efficacy. Taking 7-ethyl-10-hydroxy camptothecin (SN38) as a model anticancer drug, the co-assembled SN38-GY-CCYRGD nanoparticles significantly enhance the water solubility of SN38 by more than three orders of magnitude. The as-prepared nanoparticles can effectively kill cancer cells, e.g., human small cell lung cancer (A549) cells with a notable cell mortality rate of 71%. Mice experimental results demonstrate the nanoparticles' efficient targeting capability, marked reducing the toxicity to normal tissues while improving antitumor efficacy. This work presents a novel drug delivery method, integrating effective, targeted, and safe strategies into a comprehensive carrier system, designed for the administration of hydrophobic anticancer drugs.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38651004

RESUMO

Radiomics has been widely recognized for its effectiveness in decoding tumor phenotypes through the extraction of quantitative imaging features. However, the robustness of radiomic methods to estimate clinically relevant biomarkers non-invasively remains largely untested. In this study, we propose Cascaded Data Processing Network (CDPNet), a radiomic feature learning method to predict tumor molecular status from medical images. We apply CDPNet to an epigenetic case, specifically targeting the estimation of O6-methylguanine-DNA-methyltransferase (MGMT) promoter methylation from Magnetic Resonance Imaging (MRI) scans of glioblastoma patients. CDPNet has three components: 1) Principal Component Analysis (PCA), 2) Fisher Linear Discriminant (FLD), and 3) a combination of hashing and blockwise histograms. The outlined architectural framework capitalizes on PCA to reconstruct input image patches, followed by FLD to extract discriminative filter banks, and finally using binary hashing and blockwise histogram module for indexing, pooling, and feature generation. To validate the effectiveness of CDPNet, we conducted an exhaustive evaluation on a comprehensive retrospective cohort comprising 484 IDH-wildtype glioblastoma patients with pre-operative multi-parametric MRI scans (T1, T1-Gd, T2, and T2-FLAIR). The prediction of MGMT promoter methylation status was cast as a binary classification problem. The developed model underwent rigorous training via 10-fold cross-validation on a discovery cohort of 446 patients. Subsequently, the model's performance was evaluated on a distinct and previously unseen replication cohort of 38 patients. Our method achieved an accuracy of 70.11% and an area under the curve of 0.71 (95% CI: 0.65 - 0.74).

19.
Water Res ; 256: 121571, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38583332

RESUMO

'Candidatus Methanoperedens nitroreducens' is an archaeal methanotroph with global importance that links carbon and nitrogen cycles and great potential for sustainable operation of wastewater treatment. It has been reported to mediate the anaerobic oxidation of methane through a reverse methanogenesis pathway while reducing nitrate to nitrite. Here, we demonstrate that 'Ca. M. nitroreducens' reduces ferric iron forming ammonium (23.1 %) and nitrous oxide (N2O, 46.5 %) from nitrate. These results are supported with the upregulation of genes coding for proteins responsible for dissimilatory nitrate reduction to ammonium (nrfA), N2O formation (norV, cyt P460), and multiple multiheme c-type cytochromes for ferric iron reduction. Concomitantly, an increase in the N2O-reducing SJA-28 lineage and a decrease in the nitrite-reducing 'Candidatus Methylomirabilis oxyfera' are consistent with the changes in 'Ca. M. nitroreducens' end products. These findings demonstrate the highly flexible physiology of 'Ca. M. nitroreducens' in anaerobic ecosystems with diverse electron acceptor conditions, and further reveals its roles in linking methane oxidation to global biogeochemical cycles. 'Ca. M. nitroreducens' could significantly affect the bioavailability of nitrogen sources as well as the emission of greenhouse gas in natural ecosystems and wastewater treatment plants.

20.
Angew Chem Int Ed Engl ; : e202402693, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38586976

RESUMO

As an effective method to modulate the physicochemical properties of materials, crystal phase engineering, especially hetero-phase, plays an important role in developing high-performance photocatalysts. However, it is still a huge challenge but significant to construct porous hetero-phase nanostructures with adjustable band structures. As a kind of unique porous crystalline materials, metal-organic frameworks (MOFs) might be the appropriate candidate, but the MOF-based hetero-phase is rarely reported. Herein, we developed a secondary building unit (SBU) regulating strategy to prepare two crystal phases of Ti-MOFs constructed by titanium and 1,4-dicarboxybenzene, i.e., COK and MIL-125. Besides, COK/MIL-125 hetero-phase was further constructed. In the photocatalytic hydrogen evolution reaction, COK/MIL-125 possessed the highest H2 yield compared to COK and MIL-125, ascribing to the Z-scheme homojunction at hetero-phase interface. Furthermore, by decorating with amino groups (i.e., NH2-COK/NH2-MIL-125), the light absorbing capacity was broadened to visible-light region, and the visible-light-driven H2 yield was greatly improved. Briefly, the MOF-based hetero-phase possesses periodic channel structures and molecularly adjustable band structures, which is scarce in traditional organic or inorganic materials. As a proof of concept, our work not only highlights the development of MOF-based hetero-phase nanostructures, but also paves a novel avenue for designing high-performance photocatalysts.

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