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1.
Oxid Med Cell Longev ; 2022: 6687626, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35340212

RESUMO

Background and Aims: Elevated serum uric acid (SUA) is associated with an increased risk of nonalcoholic fatty liver disease (NAFLD); however, whether this association is causal is undetermined. Methods: Each participant from the Dongfeng-Tongji cohort study based on 27,009 retirees was interviewed face-to-face following a clinical examination. Covariance, logistic regression analysis, and instrumental variables were used to assess associations between SUA and (severity of) NAFLD and the causal link. Results: Among 8,429 subjects free of NAFLD at baseline, 2,007 participants developed NAFLD after 5 years of follow-up. The multivariable-adjusted odds ratio (OR) for NAFLD for individuals in the fourth quartile of SUA level versus those in the first was 1.71 (95% CI: 1.45-2.01, P for trend <0.001) and was more dramatic in women or normal-weight persons. Furthermore, SUA was materially associated with greater mean markers of hepatic necroinflammation and greater probabilities of fibrosis. In genetic analyses, both single nucleotide polymorphisms (rs11722228 to SLC2A9 and rs2231142 to ABCG2) were pronouncedly associated with increased SUA concentrations, ranging from 0.19 to 0.22 mg/dl. No significant associations were observed between SNPs and potential confounders. No association was observed between the SUA-increasing allele and NAFLD, with an OR of 0.98 (95% CI: 0.90-1.08) per genetic score. This was not significantly different (P = 0.25) from what was expected (1.03, 95% CI: 1.03-1.03). Conclusions: SUA was positively associated with NAFLD incidence especially in female and normal-weight individuals and the suspected progression risk of newly developed NAFLD. However, the Mendelian randomization analyses lend no causal evidence, suggesting high SUA as a marker and not a cause of NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Ácido Úrico , Estudos de Coortes , Feminino , Proteínas Facilitadoras de Transporte de Glucose , Humanos , Hepatopatia Gordurosa não Alcoólica/genética , Razão de Chances , Fatores de Risco
2.
Br J Soc Psychol ; 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513772

RESUMO

Studies on cyberbullying have revealed an inconsistent relationship between trait empathy and bystanders' aggressive tendencies towards victims. We believe that these studies have overlooked the role of social exclusion. We infer that high-severity social exclusion suppresses the negative relationship between trait empathy and bystanders' aggressive tendencies. In Study 1, 226 participants read a news report concerning a singer's humiliation by netizens due to lack of talent. The results revealed that trait empathy predicted lower aggressive tendencies towards the singer for participants with fewer experiences of social exclusion. However, trait empathy was unrelated to aggressive tendencies for participants with more experiences of social exclusion. In Study 2, 146 participants were randomly assigned to a low-severity or a high-severity social exclusion condition and were required to recall their experiences of low- or high-severity social exclusion, respectively. The results demonstrated that in the low-severity condition, trait empathy was negatively associated with participants' aggressive tendencies towards the singer and this relationship was mediated by state empathy. However, there was no evidence that the process was at work in the high-severity condition. This study further presents implications and directions for future research.

3.
Neural Regen Res ; 17(11): 2530-2536, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35535907

RESUMO

Spinal muscular atrophy (SMA) is a rare hereditary neuromuscular disease with a high lethality rate in infants. Variants in the homologous genes survival of motor neuron (SMN)1 and SMN2 have been reported to be SMA pathogenic factors. Previous studies showed that a high inclusion rate of SMN2 exon 7 increased SMN expression, which in turn reduced the severity of SMA. The inclusion rate of SMN2 exon 7 was higher in neural tissues than in non-neural tissues. Neuro-oncological ventral antigen (NOVA) is a splicing factor that is specifically and highly expressed in neurons. It plays a key role in nervous system development and in the induction of nervous system diseases. However, it remains unclear whether this splicing factor affects SMA. In this study, we analyzed the inclusion of SMN2 exon 7 in different tissues in a mouse model of SMA (genotype smn-/-SMN22tg/0) and littermate controls (genotype smn+/-SMN22tg/0). We found that inclusion level of SMN2 exon 7 was high in the brain and spinal cord tissue, and that NOVA1 was also highly expressed in nervous system tissues. In addition, SMN2 exon 7 and NOVA1 were expressed synchronously in the central nervous system. We further investigated the effects of NOVA1 on disease and found that the number of neurons in the anterior horn of spinal cord decreased in the mouse model of SMA during postnatal days 1-7, and that NOVA1 expression levels in motor neurons decreased simultaneously as spinal muscular atrophy developed. We also found that in vitro expression of NOVA1 increased the inclusion of SMN2 exon 7 and expression of the SMN2 protein in the U87MG cell line, whereas the opposite was observed when NOVA1 was knocked down. Finally, point mutation and RNA pull-down showed that the UCAC motif in SMN2 exon 7 plays a critical role in NOVA1 binding and promoting the inclusion of exon 7. Moreover, CA was more essential for the inclusion of exon 7 than the order of Y residues in the motif. Collectively, these findings indicate that NOVA1 interacts with the UCAC motif in exon 7 of SMN2, thereby enhancing inclusion of exon 7 in SMN2, which in turn increases expression of the SMN protein.

4.
Nanotechnology ; 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35523088

RESUMO

Hole transport layer (HTL) plays a critical role in perovskite solar cells (PSCs). We focus on the improvement of PSCs performance with MoS2 nanosheets as the anode buffer layer in the inverted photovoltaic structure. PSC with single MoS2 buffer layer shows poor performance in power conversion efficiency (PCE) and the long-term stability. By combination of MoS2and Poly[bis(4-phenyl) (2,4,6-trimethylphenyl) amine] (PTAA) as double-layer HTL, the PCE is improved to 18.47%, while the control device with PTAA alone shows a PCE of 14.48%. The same phenomenon is also found in 2D PSCs. For double-layer HTL devices, the PCE reaches 13.19%, and the corresponding PCE of the control group using PTAA alone is 10.13%. This significant improvement is attributed to the reduced interface resistance and improved hole extraction ability as shown by the electric impedance spectroscopy and fluorescence spectroscopy. In addition, the improved device exhibits better stability because the PCE still maintains 66% of the initial value after 500 hours of storage, which is higher than the 47% of the remaining PCE from device based on single PTAA or MoS2. Our results demonstrate the potential of polymer/inorganic nanomaterial as a double-layer buffer material for PSCs.

5.
Ecotoxicol Environ Saf ; 238: 113605, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35561546

RESUMO

The analysis of soil bacterial community has guiding significance for fully utilization of soil microbial resources. The results of high-throughput sequencing (HTS) showed that the bacteria in the three sulfometuron-methyl contaminated soil samples were mainly composed of 677 genera, including Phenylobacterium, Bacillus, belonging to 28 phyla, including Proteobacteria, Firmicutes. The diversity and richness of bacterial community decreased with the increase in sulfometuron-methyl concentration. In addition, sulfometuron-methyl could also affect the soil bacterial function based on PICRUSt functional predictive analysis. Combined with the results of HTS and phylogenetic molecular ecological networks (pMENs), 12 genera, including Ralstonia (Pi=0.64), were identified as the key soil microflora (intra-module connectivity Zi ≥ 2.5 or inter-module connectivity Pi ≥ 0.62), and the abundance of Ralstonia significantly increased with the concentration of sulfometuron-methyl, indicating that the strains of this genus might be the potential degrading bacteria and could form a stable relationship with indigenous microorganisms. Among the isolated bacteria of genus Ralstonia, one strain, named Ralstonia sp. JM-1, was verified to possess higher sulfometuron-methyl degradation efficiency, which completely degraded 20 mg L-1 of sulfometuron-methyl within 96 h. Furthermore, the immobilized strains generated by the mixture of 2.0 g bamboo charcoal and 3.0 mL bacterial suspension for 24 h had the highest sulfometuron-methyl degradation rate than that under other conditions, and the dynamic process degrading 10-30 mg L-1 of sulfometuron-methyl conforms to the zero-order kinetic equation. The bioremediation of contaminated soil showed the immobilized strains could completely degrade sulfometuron-methyl (1.39 mg kg-1) in contaminated soil within 9 d, which is higher than that application of strains in the free state (74.8%). This study could provide ideas for the isolation of functional strains and a theoretical basis for the bioremediation of STM and other contaminated soils.

6.
J Agric Food Chem ; 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35549340

RESUMO

The application of agrochemicals is critical to global food safety. Nowadays, environmentally friendly green agrochemicals are the trend in field crop protection. The research and development of nematicides absorbed more attention as a typical representation of agrochemicals. This review describes the origin of recently commercialized nematicides, the application of bioisosterism and scaffold hopping in the discovery and optimization of agrochemicals, especially nematicides, and novel bioisosteric design strategies for the identification of fluensulfone analogues. Pesticide repurposing, high-throughput screening, computer-aided drug design, and incorporation of known pharmacophoric fragments have been the most successful approach for the discovery of new nematicides. As outlined, the strategies of bioisosteric replacements and scaffold hopping have been very successful approaches in the search for new nematicides for sustainable crop protection. In the exploration of novel fluensulfone analogues with nematicidal activity, bioisosteric replacement of sulfone by amide, chain extension by insertion of a methylene group, and reversal of the amide group have proven to be successful approaches and yielded new and highly active fluensulfone analogues. These attempts might result in compounds with an optimal balance of steric, hydrophobic, electronic, and hydrogen-bonding properties and contribute to deal with the complex problem during the research and development of new nematicides. Further ideas are also put forward to provide new approaches for the molecular design of nematicides.

7.
J Exp Clin Cancer Res ; 41(1): 173, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35549739

RESUMO

BACKGROUND: The ETS transcription factor GABPA has long been thought of as an oncogenic factor and recently suggested as a target for cancer therapy due to its critical effect on telomerase activation, but the role of GABPA in clear cell renal cell carcinoma (ccRCC) is unclear. In addition, ccRCC is characterized by metabolic reprograming with aberrant accumulation of L-2-hydroxyglurate (L-2HG), an oncometabolite that has been shown to promote ccRCC development and progression by inducing DNA methylation, however, its downstream effectors remain poorly defined. METHODS: siRNAs and expression vectors were used to manipulate the expression of GABPA and other factors and to determine cellular/molecular and phenotypic alterations. RNA sequencing and ChIP assays were performed to identify GABPA target genes. A human ccRCC xenograft model in mice was used to evaluate the effect of GABPA overexpression on in vivo tumorigenesis and metastasis. ccRCC cells were incubated with L-2-HG to analyze GABPA expression and methylation. We carried out immunohistochemistry on patient specimens and TCGA dataset analyses to assess the effect of GABPA on ccRCC survival. RESULTS: GABPA depletion, although inhibiting telomerase expression, robustly enhanced proliferation, invasion and stemness of ccRCC cells, whereas GABPA overexpression exhibited opposite effects, strongly inhibiting in vivo metastasis and carcinogenesis. TGFBR2 was identified as the GABPA target gene through which GABPA governed the TGFß signaling to dictate ccRCC phenotypes. GABPA and TGFBR2 phenocopies each other in ccRCC cells. Higher GABPA or TGFBR2 expression predicted longer survival in patients with ccRCC. Incubation of ccRCC cells with L-2-HG mimics GABPA-knockdown-mediated phenotypic alterations. L-2-HG silenced the expression of GABPA in ccRCC cells by increasing its methylation. CONCLUSIONS: GABPA acts as a tumor suppressor by stimulating TGFBR2 expression and TGFß signaling, while L-2-HG epigenetically inhibits GABPA expression, disrupting the GABPA-TGFß loop to drive ccRCC aggressiveness. These results exemplify how oncometabolites erase tumor suppressive function for cancer development/progression. Restoring GABPA expression using DNA methylation inhibitors or other approaches, rather than targeting it, may be a novel strategy for ccRCC therapy.

8.
Gene ; : 146565, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35569770

RESUMO

BACKGROUND: Hypoxia is a primary inducer of cardiomyocyte injury, its significant marker being hypoxia-induced cardiomyocyte apoptosis. Nuclear respiratory factor-1 (NRF-1) and hypoxia-inducible factor-1α (HIF-1α) are transcriptional regulatory elements implicated in multiple biological functions, including oxidative stress response. However, their roles in hypoxia-induced cardiomyocyte apoptosis remain unknown. The effect HIF-α, together with NRF-1, exerts on cardiomyocyte apoptosis also remains unclear. METHODS: We established a myocardial hypoxia model and investigated the effects of these proteins on the proliferation and apoptosis of rat cardiomyocytes (H9C2) under hypoxia. Further, we examined the association between NRF-1 and HIF-1α to improve the current understanding of NRF-1 anti-apoptotic mechanisms. RESULTS: The results show that NRF-1 and HIF-1α are important anti-apoptotic molecules in H9C2 cells under hypoxia, although their regulatory mechanisms differ. NRF-1 could bind to the promoter region of Hif1a and negatively regulate its expression. Additionally, HIF-1ß exhibited competitive binding with NRF-1 and HIF-1α, demonstrating a synergism between NRF-1 and the peroxisome proliferator-activated receptor-gamma coactivator-1α. CONCLUSION: These results indicate that cardiomyocytes can regulate different molecular patterns to tolerate hypoxia, providing a novel methodological framework for studying cardiomyocyte apoptosis under hypoxia.

9.
Ann Transl Med ; 10(8): 456, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35571419

RESUMO

Background: Oncostatin M (OSM) is reported to be involved in many stages of atherosclerosis, including endothelial dysfunction, chronic inflammation, and smooth muscle cell migration. This study explored the effects of OSM on foam cell formation and its corresponding molecular mechanisms. Methods: THP-1 cells were treated with phorbol-12-myristate-13-acetate (PMA) to induce macrophage differentiation and were then exposed to oxidized low-density lipoprotein (ox-LDL). OSM expression was analyzed by quantitative reverse transcription-polymerase chain reaction, Western blotting, and enzyme-linked immunosorbent assay (ELISA). OSM-specific small interfering RNAs (siRNAs) were transfected into THP-1 macrophages. The effects of OSM silencing were evaluated by Oil Red O staining, ELISA, and Western blotting. Moreover, the activation of NLR family pyrin domain containing 3 (NLRP3) inflammasomes was detected by western blotting and immunofluorescence. Results: OSM was highly expressed in THP-1 macrophages in a time- and dose-dependent fashion. Silencing OSM significantly reduced the total cholesterol content and Oil Red O staining levels in ox-LDL-treated macrophages. Silencing OSM significantly inhibited ox-LDL-induced cytokine release, including TNF-α, IL-1ß, IL-6, and IL-18. Ox-LDL activated p65 and NLRP3, which further induced caspase-1 cleavage, apoptosis-associated, speck-like protein containing a caspase-1 recruitment domain (ASC) upregulation, and gasdermin-D (GSDMD)-N fragmentation. Overexpression of NLRP3 significantly reversed the effects of OSM silencing on ox-LDL-induced foam cell formation and inflammation. Conclusions: OSM was highly expressed in the cell model of atherosclerosis. OSM has a promoting role in ox-LDL-induced foam cell formation and inflammation via the activation of p65-NLRP3 signaling pathways. Silencing OSM may be has benefit in treating atherosclerosis.

10.
Chem Mater ; 34(7): 3440-3450, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35572784

RESUMO

Frustrated lanthanide oxides with dense magnetic lattices are of fundamental interest for their potential in cryogenic refrigeration due to a large ground state entropy and suppressed ordering temperatures but can often be limited by short-range correlations. Here, we present examples of frustrated fcc oxides, Ba2GdSbO6 and Sr2GdSbO6, and the new site-disordered analogue Ca2GdSbO6 ([CaGd] A [CaSb] B O6), in which the magnetocaloric effect is influenced by minimal superexchange (J 1 ∼ 10 mK). We report on the crystal structures using powder X-ray diffraction and the bulk magnetic properties through low-field susceptibility and isothermal magnetization measurements. The Gd compounds exhibit a magnetic entropy change of up to -15.8 J/K/molGd in a field of 7 T at 2 K, a 20% excess compared to the value of -13.0 J/K/molGd for a standard in magnetic refrigeration, Gd3Ga5O12. Heat capacity measurements indicate a lack of magnetic ordering down to 0.4 K for Ba2GdSbO6 and Sr2GdSbO6, suggesting cooling down through the liquid 4-He regime. A mean-field model is used to elucidate the role of primarily free-spin behavior in the magnetocaloric performance of these compounds in comparison to other top-performing Gd-based oxides. The chemical flexibility of the double perovskites raises the possibility of further enhancement of the magnetocaloric effect in the Gd3+ fcc lattices.

11.
J Thorac Dis ; 14(4): 841-850, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35572869

RESUMO

Background: The influences of marital status on cardiovascular death risk in patients with breast cancer remained unclear. This study aimed to evaluate the associations of different marital status with cardiovascular death risk in patients with breast cancer. Methods: A total of 182,666 female breast cancer patients were enrolled in this study from the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2014, and was divided into two groups: married (N=107,043) and unmarried (N=75,623). A 1:1 propensity score matching (PSM) was applied to reduce inter-group bias between the two groups. Competing-risks model was used to assess the associations between different marital status and cardiovascular death risk in patients with breast cancer. Results: After PSM, marital status was an independent predictor for cardiovascular death in patients with breast cancer. Unmarried condition was associated with increased cardiovascular death risk than married condition among breast cancer patients [unadjusted model: hazard ratio (HR) =2.012, 95% confidence interval (CI): 1.835-2.208, P<0.001; Model 1: HR =1.958, 95% CI: 1.785-2.148, P<0.001; Model 2: HR =1.954, 95% CI: 1.781-2.144, P<0.001; Model 3: HR =1.920, 95% CI: 1.748-2.107, P<0.001]. With the exception of separated condition (adjusted HR =0.886, 95% CI: 0.474-1.658, P=0.705), further unmarried subgroups analysis showed that the other three unmarried status were associated with increased cardiovascular death risk as follows: single (adjusted HR =1.623, 95% CI: 1.421-1.853, P<0.001), divorced (adjusted HR =1.394, 95% CI: 1.209-1.608, P<0.001), and widowed (adjusted HR =2.460, 95% CI: 2.227-2.717, P<0.001). In particularly, widowed condition showed the highest cardiovascular death risk in all 4 unmarried subgroups. Conclusions: Unmarried condition (e.g., single, divorced and widowed) was associated with elevated cardiovascular death risk compared with their married counterparts in patients with breast cancer, suggesting that more attention and humanistic care should be paid to unmarried breast cancer patients (especially the widowed patients) in the management of female breast cancer patients.

12.
Am J Transl Res ; 14(4): 2244-2255, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35559380

RESUMO

With the COVID-19 epidemic quickly under control in China in the early stage of 2020, global cooperation/communications may pose great challenges to epidemic control and prevention in the country. Large-scale spread by asymptomatic carriers was a concern. We obtained data on new cluster outbreak regions with COVID-19 caused by asymptomatic carriers from June 2020 to May 2021 in China, and reported the epidemiological characteristics, the possible routes of viral transmission and infection, and different control strategies. These results show the importance of regular screening for high-risk populations and differential management strategies for epidemic control, which provide an objective basis for suppressing the spread of the SARS-CoV-2 virus. These experiences can be used as a reference to minimize the subsequent spread of virus mutants in various places.

13.
Ying Yong Sheng Tai Xue Bao ; 33(4): 1083-1090, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35543063

RESUMO

With the Quanfuzhuang River basin located at Hani Rice Terrace core region as study area, we analyzed the isotopic composition and the effects of 12 surface water sampling sites for the forest landscape type and terrace landscape type from May 2015 to April 2016. The results showed that: 1) For the variation of isotope composition, both the average value and the variation range of δ18O in surface water under forest patches were smaller than that under terrace patches. 2) The overall elevation effect of the hydrogen and oxygen stable isotopes in surface water was obvious, except that in August and March, which could be expressed as the linear regression equation δ18O=-0.012H+13.84 (r=-0.83, n=12). 3) The altitude gradient of δ18O in surface water was -1.2‰·(100 m)-1, which was not the true altitude gradient affected by precipitation but by landscape gradient of δ18O in surface water between forest patches and terrace patches. 4) Under the "Forest-Terrace" landscape pattern, the δ18O differences in surface water between forest patches and terrace patches enhanced the elevation effect. Therefore, when landscape heterogeneity was strong, isotopic effect was strengthened, even with opposite isotope effect.

14.
Biochem Res Int ; 2022: 9948229, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35528843

RESUMO

Objective: To study the mechanism by which miR-21 regulates the differentiation and function of Th17/Treg cells in sepsis. Methods: A rat model with sepsis was made by cecal ligation and puncture (CLP). Then, some of the septic rats were transfected with miR-21 mimic or inhibitor by liposome. At 48 hours, lymphocytes and plasma from septic rats were isolated for further experimental detection. The expression of miR-21 in lymphocytes was detected by Polymerase Chain Reaction (PCR); the differentiation of Th17/Treg cells was counted by flow cytometry; lymphocyte apoptosis was observed by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay. The caspase-3/9 proteins were tested by Western blot; IL-10 and IL-17 were detected by enzyme-linked immunosorbent assay (ELISA). Results: Compared with the sepsis group (SP group), the Th17 cells increased significantly, the Treg cells decreased significantly, the apoptosis rate of lymphocytes decreased significantly, the mRNA and proteins of caspase-3/9 decreased significantly, the IL-17 decreased, and the IL-10 increased in the sepsis group transfected with miR-21 (SP + miR-21 mimic group). After transfection of miR-21 inhibitor, the results were almost opposite to those of SP + miR-21 mimic group. Conclusions: The differentiation and function of Th17/Treg cells were regulated by miR-21 in sepsis through caspase pathway.

15.
ACS Sens ; 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35546283

RESUMO

Low-dimensional semiconductor materials, such as single-walled carbon nanotubes, two-dimensional (2D) atomic crystals, and organic frameworks, have been widely adapted as ideal platforms to construct various chemo/biosensors with satisfying sensitivity. However, the general drawbacks in chemiresistive devices, including high operation temperatures, low response to low-polarity molecules, and poor selectivity, have limited their real-world applications. In this study, 2D materials (graphene, MoS2, and WSe2) were systematically functionalized with series of monodispersed single atomic sites (Pt, Co, and Ru) through a facile approach to construct single-atom sensors (SASs) for the detection of VOCs at room temperature. The structural and catalytic characteristics of SAs successfully translated into enhanced gas-sensing performance, with a 1-2 orders of magnitude increase in relative response to ethanol (@5 ppm) and acetone (@20 ppm) vapors (in all M-2D SASs as compared to pristine substrates), high selectivity to VOCs against relative humidity (M-WSe2 SASs), and fast response/recovery time (11/58 s for Pt-Graphene and 22/48 s for Pt-MoS2 to 50 ppm ethanol, 9/57 s for Pt-Graphene and 15/75 s for Pt-MoS2 to 200 ppm acetone) that are several times faster than the pristine 2D materials. Density functional theory (DFT) calculations revealed the signaling mechanism in SASs, and the data were further trained to build machine learning (ML) models for predicting the adsorption energies and sensing performance using the features of adsorption heights, metal charge, and charge transfer between the adsorbed VOCs and SASs sites. Finally, the rich combination of the metal single atoms and 2D atomic crystal supports were converted to cross-sensitive SA sensor array that allows for detection and identification of different VOCs.

16.
Spectrochim Acta A Mol Biomol Spectrosc ; 278: 121324, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35567822

RESUMO

The construction of multi-modal detection methods has attracted widespread attention in the field of biosensing due to their high sensitivity and strong anti-interference ability. In this manuscript, we developed colorimetric and ratiometric fluorescence dual-signal optical methods based on cerium-based nanoparticles (Ce NPs) for the sensitive detection of vitamin C (VC). The catalysis of Ce NPs with excellent peroxidase-like activity upon the reaction of H2O2 with OPD was occurred, promoting the oxidation of o-phenylenediamine (OPD) to generate 2,3-diaminophennazine (OPDox) with an obvious absorption peak at 420 nm and an emission peak at 565 nm. In the presence of VC, VC not only inhibited the generation of OPDox, but also induced the formation of quinoxaline with an obvious absorption peak at 336 nm and an emission peak at 430 nm. This can be visually observed and monitored by measuring the absorbance of peak at 336 nm (A336) and the ratiometric fluorescence intensity (F430/F565). Therefore, the dual-signal methods are constructed for the detection of VC. The detection lower detection limits are 8.0 µM and 8.4 µM when using the fluorescence and colorimetric signals, respectively. Furthermore, the proposed methods are successfully applied to the detection of VC in practical samples with satisfactory results.

17.
J Agric Food Chem ; 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35521920

RESUMO

5-Methyltetrahydrofolate (5-MTHF) is the predominant folate form in human plasma, which has been widely used as a nutraceutical. However, the microbial synthesis of 5-MTHF is currently inefficient, limiting green and sustainable 5-MTHF production. In this study, the Generally Regarded As Safe (GRAS) microorganism Bacillus subtilis was engineered as the 5-MTHF production host. Three precursor supply modules were first optimized by modular engineering for strengthening the supply of guanosine-5-triphosphate (GTP) and p-aminobenzoic acid (pABA). Next, the impact of genome-wide gene expression on 5-MTHF biosynthesis was evaluated using transcriptome analyses, which identified key genes for 5-MTHF production. The effects of potential genes on 5-MTHF synthesis were verified by observing the genes' up-regulated by strong promoter P566 and those down-regulated by inhibition through the clustered regularly interspaced short palindromic repeat interference (CRISPRi). Finally, a key gene for improved 5-MTHF biosynthesis, comGC, was integrated into the genome of modular engineered strain B89 for its overexpression and facilitating efficient 5-MTHF synthesis, reaching 3.41 ± 0.10 mg/L with a productivity of 0.21 mg/L/h, which was the highest level achieved by microbial synthesis. The engineered 5-MTHF-producing B. subtilis developed in this work lays the foundation of further enhancing 5-MTHF production by microbial fermentation, which can be used for isolation and purification of 5-MTHF as food and nutraceutical ingredients.

18.
J Sep Sci ; 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35579607

RESUMO

In this study, monodisperse magnetic carbon microspheres were successfully synthesized through the carbonization of phenolic resin encapsulated Fe3 O4 core-shell structures. The magnetic carbon microspheres showed high performance in ultrafast extraction and separation of trace triazine herbicides from environmental water samples. Under optimized conditions, both the adsorption and desorption processes could be achieved in 2 min, and the maximum adsorption capacity for simazine and prometryn were 387.6 and 448.5 µg/g. Coupled with HPLC-UV detection technology, the detection limit of triazine herbicides was in the range of 0.30-0.41 ng/mL. The mean recoveries ranged from 81.44 to 91.03% with relative standard deviations lower than 7.47%. The excellent magnetic solid phase extraction performance indicates that magnetic carbon microspheres are promising candidate adsorbent for the fast analysis of environmental contaminants. This article is protected by copyright. All rights reserved.

19.
Future Oncol ; 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35440164

RESUMO

The success of sotorasib (AMG-510) and adagrasib (MRTX-849) has resolved the problem of non-availability of drugs for patients with KRASG12C-mutated non-small-cell lung cancer. However, more research is required before these drugs can be introduced as a first-line treatment for those patients, and there are no available drugs for other non-G12C-mutated patients so far; therefore, immunotherapy remains the optimal first-line treatment in this situation. The role of KRAS in affecting the response to immunotherapy in non-small-cell lung cancer has not been fully elucidated. The purpose of this review was to summarize the impact of KRAS mutations, a highly heterogeneous group, on immunotherapy to provide clinicians and researchers with relevant information that can help guide decision-making.


Sotorasib (AMG-510) and adagrasib (MRTX-849) have changed the problem of non-availability of targeted drugs for patients with KRAS-mutated lung cancer. However, thus far, immunotherapy remains the optimal treatment for lung cancer patients with KRAS mutations who have not received previous treatment. The role of KRAS in affecting the response to immunotherapy in non-small-cell lung cancer has not been fully elucidated. The purpose of this review was to summarize the impact of KRAS mutations, a highly heterogeneous group, on immunotherapy to provide clinicians and researchers with relevant information that can help guide decision-making.

20.
Nat Nanotechnol ; 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35449409

RESUMO

Despite the remarkable progress in power conversion efficiency of perovskite solar cells, going from individual small-size devices into large-area modules while preserving their commercial competitiveness compared with other thin-film solar cells remains a challenge. Major obstacles include reduction of both the resistive losses and intrinsic defects in the electron transport layers and the reliable fabrication of high-quality large-area perovskite films. Here we report a facile solvothermal method to synthesize single-crystalline TiO2 rhombohedral nanoparticles with exposed (001) facets. Owing to their low lattice mismatch and high affinity with the perovskite absorber, their high electron mobility and their lower density of defects, single-crystalline TiO2 nanoparticle-based small-size devices achieve an efficiency of 24.05% and a fill factor of 84.7%. The devices maintain about 90% of their initial performance after continuous operation for 1,400 h. We have fabricated large-area modules and obtained a certified efficiency of 22.72% with an active area of nearly 24 cm2, which represents the highest-efficiency modules with the lowest loss in efficiency when scaling up.

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