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2.
Chem Commun (Camb) ; 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34313269

RESUMO

A space-confined strategy has been used to control the pyrolysis of two-dimensional (2D) NiCo-MOF@ZIF-L(Zn). A thin SiO2 layer as a confined space could avoid the destruction of the 2D morphology during pyrolysis and expose more active sites. The obtained NiCo-NC material exhibits high ORR and Zn-air battery performance.

3.
J Environ Manage ; 296: 113196, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34252848

RESUMO

Considering the reduction and resource utilization of landfill sludge (LS) and fresh sludge (FS), Fe2+ activated Na2S2O8 is proposed. The effects of the molar ratio of Fe2+/S2O82- and the addition of Na2S2O8 on the dewatering performance of sludge were studied by vacuum filtration experiments. Consolidation tests were conducted on the sludge with different Na2S2O8 dosage, and the compression, consolidation, and permeability characteristics of the sludge were researched. Besides, via particle size distribution (PSD) and scanning electron microscope (SEM) test, the variation of particle size of sludge was studied from the microscopic perspective. The results are as follows: the specific resistance of filtration (SRF) of LS and FS decreases by 99.3%, 95.2% at an optimal dosage (the molar ratio of (Fe2+/S2O82-) = 1, 30% Na2S2O8); the particle size of LS and FS is significantly smaller; the consolidation and permeability coefficients are increased by 1-2 orders of magnitude compared with non-conditioned sludge; the water content of LS and FS drops from 86.5% to 58.4%, 82.4%-59.7%. The research results have certain guiding significance for the in-situ treatment of sludge deep dewatering.

4.
Genes (Basel) ; 12(7)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199012

RESUMO

The YABBY family of plant-specific transcription factors play important regulatory roles during the development of leaves and floral organs, but their functions in Brassica species are incompletely understood. Here, we identified 79 YABBY genes from Arabidopsis thaliana and five Brassica species (B. rapa, B. nigra, B. oleracea, B. juncea, and B. napus). A phylogenetic analysis of YABBY proteins separated them into five clusters (YAB1-YAB5) with representatives from all five Brassica species, suggesting a high degree of conservation and similar functions within each subfamily. We determined the gene structure, chromosomal location, and expression patterns of the 21 BnaYAB genes identified, revealing extensive duplication events and gene loss following polyploidization. Changes in exon-intron structure during evolution may have driven differentiation in expression patterns and functions, combined with purifying selection, as evidenced by Ka/Ks values below 1. Based on transcriptome sequencing data, we selected nine genes with high expression at the flowering stage. qRT-PCR analysis further indicated that most BnaYAB family members are tissue-specific and exhibit different expression patterns in various tissues and organs of B. napus. This preliminary study of the characteristics of the YABBY gene family in the Brassica napus genome provides theoretical support and reference for the later functional identification of the family genes.

5.
Nutrients ; 13(7)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202423

RESUMO

BACKGROUND: Bone mineral acquisition during adolescence is crucial for maximizing peak bone mass. Fat mass (FM) and bone mass are closely related. This study investigated the association of FM distribution with bone mass in Chinese male adolescents. METHOD: A total of 693 male adolescents aged 10-18 years were recruited from a secondary school in Jiangmen, China. Their bone mass and body composition were measured by quantitative ultrasound and bioelectrical impedance analysis, respectively. The associations of the measures of fat distribution with bone parameters, i.e., broadband ultrasound attenuation, speed of sound (SOS), and stiffness index (SI), were analyzed using multiple linear regression. Age, height, body mass index, stage of puberty, physical activity, sedentary behavior, dietary energy intake, and dietary calcium and vitamin D intake were adjusted in the model. Further subgroup analyses of prepubertal and pubertal participants were conducted. RESULTS: The measures of fat distribution showed negative associations with SOS and SI in total subjects (p < 0.010). In prepubertal boys, the measures of fat distribution were only associated with SOS (ß = -0.377 to -0.393, p < 0.050). In pubertal boys, the measures of fat distribution had associations with all bone parameters (ß = -0.205 to -0.584, p < 0.050). The strongest association was between trunk FM and SOS (ß = -0.584, p < 0.001). CONCLUSION: This study supported that the measures of fat distribution were negatively associated with bone parameters in Chinese male adolescents. Trunk FM had the strongest association with bone parameter. These associations appear to be stronger in pubertal boys than in prepubertal boys.

6.
BMC Plant Biol ; 21(1): 346, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301195

RESUMO

BACKGROUND: Root system architecture (RSA), which is determined by the crown root angle (CRA), crown root diameter (CRD), and crown root number (CRN), is an important factor affecting the ability of plants to obtain nutrients and water from the soil. However, the genetic mechanisms regulating crown root traits in the field remain unclear. METHODS: In this study, the CRA, CRD, and CRN of 316 diverse maize inbred lines were analysed in three field trials. Substantial phenotypic variations were observed for the three crown root traits in all environments. A genome-wide association study was conducted using two single-locus methods (GLM and MLM) and three multi-locus methods (FarmCPU, FASTmrMLM, and FASTmrEMMA) with 140,421 SNP. RESULTS: A total of 38 QTL including 126 SNPs were detected for CRA, CRD, and CRN. Additionally, 113 candidate genes within 50 kb of the significant SNPs were identified. Combining the gene annotation information and the expression profiles, 3 genes including GRMZM2G141205 (IAA), GRMZM2G138511 (HSP) and GRMZM2G175910 (cytokinin-O-glucosyltransferase) were selected as potentially candidate genes related to crown root development. Moreover, GRMZM2G141205, encoding an AUX/IAA transcriptional regulator, was resequenced in all tested lines. Five variants were identified as significantly associated with CRN in different environments. Four haplotypes were detected based on these significant variants, and Hap1 has more CRN. CONCLUSIONS: These findings may be useful for clarifying the genetic basis of maize root system architecture. Furthermore, the identified candidate genes and variants may be relevant for breeding new maize varieties with root traits suitable for diverse environmental conditions.

9.
Br J Psychol ; 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34260744

RESUMO

Many citizens around the globe believe conspiracy theories. Why are conspiracy theories so appealing? Here, we propose that conspiracy theories elicit intense emotions independent of emotional valence. People therefore find conspiracy theories entertaining - that is, narratives that people perceive as interesting, exciting, and attention-grabbing - and such entertainment appraisals are positively associated with belief in them. Five studies supported these ideas. Participants were exposed to either a conspiratorial or a non-conspiratorial text about the Notre Dame fire (Study 1) or the death of Jeffrey Epstein (preregistered Study 2). The conspiratorial text elicited stronger entertainment appraisals and intense emotions (independent of emotional valence) than the non-conspiratorial text; moreover, entertainment appraisals mediated the effects of the manipulation on conspiracy beliefs. Study 3 indicated that participants endorsed stronger conspiracy beliefs when an election event was described in an entertaining rather than a boring manner. Subsequent findings revealed that both organisational (Study 4) and societal conspiracy beliefs (Study 5) are positively associated with sensation seeking - a trait characterised by a preference for exciting and intense experiences. We conclude that one reason why people believe conspiracy theories is because they find them entertaining.

10.
J Comp Neurol ; 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34212389

RESUMO

Accumulation of amyloid ß (Aß) in the brain is a hallmark of Alzheimer's disease (AD). We previously showed that ErbB4 in parvalbumin (PV)-positive interneurons was associated with Aß-induced cognitive deficits; however, the underlying mechanism remains undetermined. Here we found that specific deletion of ErbB4 in PV neurons significantly attenuated oligomeric Aß-induced neuronal toxicity and inhibited Aß-induced decreases of PSD95 and synaptophysin. Moreover, specific ablation of ErbB4 in PV neurons altered activity-related protein c-Fos and decreased hippocampal PV neurons, especially in the dentate gyrus (DG) of hAPP-J20 mice. Furthermore, c-Jun N-terminal kinase (JNK), a protein downstream of ErbB4, was activated by Aß but not ErbB4's ligand neuregulin 1 (NRG1) ß1, suggesting different downstream pathways for Aß and NRG1ß1. JNK phosphorylation was inhibited by the ErbB4 inhibitor AG1478 and by pretreatment with NRG1ß1. More importantly, siRNA knockdown of ErbB4 decreased JNK phosphorylation and expression, tau phosphorylation at Ser396 and Thr 205, and Bax expression. Therefore, ErbB4 might mediate Aß-induced neuropathology through the JNK/tau pathway and represent a potential therapeutic target in patients with AD.

11.
Front Immunol ; 12: 673636, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34276662

RESUMO

Graft-versus-host disease (GVHD), especially steroid-refractory GVHD, remains a life-threatening complication after hematopoietic stem cell transplantation (HSCT). The effect of the JAK1/2 kinase inhibitor ruxolitinib on treating steroid-refractory acute GVHD has been verified by the REACH1/2 study; however, its safety and efficacy in patients with steroid-refractory chronic GVHD (SR-cGVHD) remain unclear. In this retrospective study, 70 patients received ruxolitinib as a salvage therapy for SR-cGVHD. Twenty-four weeks after ruxolitinib treatment, the overall response rate (ORR) was 74.3% (52/70), including 34 patients who achieved complete remission (CR) and 18 who achieved partial remission (PR). The main adverse event was cytopenia, which occurred in 51.4% (36/70) of patients. After ruxolitinib treatment, the percentage of CD4 cells increased from 18.20% to 23.22% (P<0.001), while the percentages of NK (CD16+CD56+) cells and regulatory T cells (CD4+CD127 ± CD25+) decreased (P<0.001, P<0.001). Among the B cell subsets, the proportion of total B cells approximately tripled from 3.69% to 11.16% (P<0.001). Moreover, we observed a significant increase in IL-10 levels after ruxolitinib treatment (P=0.025) and a remarkable decrease in levels of suppression of tumorigenicity 2 (ST2) from 229.90 ng/ml to 72.65 ng/ml. The median follow-up after the initiation of ruxolitinib treatment was 401 (6-1076) days. The estimated one-year overall survival rate of the whole group was 66.0% (54.4-77.6%, 95% CI), and the one-year overall survival rate of patients with mild and moderate cGVHD was 69.6% (57.4-81.8%, 95% CI), which was better than that of patients with severe cGVHD (31.3%, 0.0-66.2%, 95% CI) (P=0.002). Patients who achieved a CR and PR achieved better survival outcomes (84.5%, 73.9-95.1%, 95% CI) than those who showed NR to ruxolitinib treatments (16.7%, 0-34.3%, 95% CI) (P<0.001). At the final follow-up, cGVHD relapse occurred in six patients after they reduced or continued their ruxolitinib doses. Collectively, our results suggest that ruxolitinib is potentially a safe and effective treatment for SR-cGVHD.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34206719

RESUMO

It is known that social support and empathy are beneficial for mental health. As a result of the widespread development of social media, online social support and empathy could also influence user behaviors during the development of online communities. However, few studies have examined these effects from the perspective of online mental health communities. These communities appear to be a crucial source for mental health related support, but the spread of online empathy in these communities is not well-understood. This study focused on 22 mental health related subreddits, and matched and compared users (1) who received social support with those who did not receive social support, and users (2) who received more empathic social support with those who received less empathic social support. The results showed that social support and empathy are "contagious". That is, users who received social support at their first post would be more likely to post again and provide support for others; in addition, users who received more empathic support would subsequently express a higher level of empathy to others in the future. Our findings indicate the potential chain reaction of social support and empathy in online mental health communities. Our study also provides insights into how online mental health communities might better assist people to deliver social support that can help others to deal with mental problems.

13.
J Neural Eng ; 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34284361

RESUMO

OBJECTIVE: White matter tissue takes up approximately 50,% of the human brain volume and it is widely known as a messenger conducting information between areas of the central nervous system. However, the characteristic of white matter neural activity and its potential role in movement decoding are often ignored and still remain largely unknown. In this work, we make quantitative analyses to investigate these two important questions using invasive neural recordings. APPROACH: We recorded stereo-electroencephalography (SEEG) data from 32 human subjects during a visually-cued motor task, where SEEG recordings can tap into gray and white matter electrical activity simultaneously. Using the proximal tissue density (PTD) method, we identified the location (i.e., gray or white matter) of each SEEG contact. Focusing on alpha oscillatory and high gamma activities, we compared the activation patterns between gray matter and white matter. Then, we evaluated the possible role of such white matter activation in movement decoding. MAIN RESULTS: The results show that white matter also presents activation under the task, in a similar way with the gray matter but at a significantly lower amplitude. Additionally, this work also demonstrates that combing white matter neural activities together with that of gray matter significantly promotes the movement decoding accuracy than using gray matter signals only. SIGNIFICANCE: Taking advantage of SEEG recordings from a large number of subjects, we reveal the characteristics of white matter neural signals in response to the task and demonstrate its enhancing function in movement decoding. This study highlights the importance of taking white matter activities into consideration in further scientific research and translational applications.

14.
Nat Commun ; 12(1): 4091, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215748

RESUMO

Little is known about the transcriptomic plasticity and adaptive mechanisms of circulating tumor cells (CTCs) during hematogeneous dissemination. Here we interrogate the transcriptome of 113 single CTCs from 4 different vascular sites, including hepatic vein (HV), peripheral artery (PA), peripheral vein (PV) and portal vein (PoV) using single-cell full-length RNA sequencing in hepatocellular carcinoma (HCC) patients. We reveal that the transcriptional dynamics of CTCs were associated with stress response, cell cycle and immune-evasion signaling during hematogeneous transportation. Besides, we identify chemokine CCL5 as an important mediator for CTC immune evasion. Mechanistically, overexpression of CCL5 in CTCs is transcriptionally regulated by p38-MAX signaling, which recruites regulatory T cells (Tregs) to facilitate immune escape and metastatic seeding of CTCs. Collectively, our results reveal a previously unappreciated spatial heterogeneity and an immune-escape mechanism of CTC, which may aid in designing new anti-metastasis therapeutic strategies in HCC.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Heterogeneidade Genética , Evasão da Resposta Imune , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Células Neoplásicas Circulantes/imunologia , Idoso , Animais , Biomarcadores Tumorais/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Quimiocina CCL5/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Metástase Neoplásica , Células Neoplásicas Circulantes/metabolismo , Prognóstico , RNA-Seq , Transcriptoma , Microambiente Tumoral
15.
Eur J Heart Fail ; 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34196082

RESUMO

AIMS: Whether to continue or stop mineralocorticoid receptor antagonists (MRA) after an episode of hyperkalaemia is a challenge in clinical practice. While stopping MRA may prevent recurrent hyperkalaemias, it deprives patients of their cardioprotection. We here assessed the association between stopping vs. continuing MRA therapy after hyperkalaemia and the subsequent risks of adverse health events. METHODS AND RESULTS: Observational study from the Stockholm CREAtinine Measurements (SCREAM) project 2006-2018. We identified patients initiating MRA and surviving a first-detected episode of hyperkalaemia (plasma potassium >5.0 mmol/L). Using target trial emulation methods, we assessed the association between stopping vs. continuing MRA within 6 months after hyperkalaemia and subsequent outcomes. The primary outcome was the composite of hospital admission with heart failure, stroke, myocardial infarction, or death. The secondary outcome was occurrence of another hyperkalaemia event. Among 39 518 patients initiating MRA, we identified 7366 who developed hyperkalaemia. Median age was 76 years, 45% were women and 69% had a history of heart failure. Following hyperkalaemia, 2222 (30%) discontinued treatment. Compared with continuing MRA, stopping therapy was associated with a lower 2-year risk of recurrent hyperkalaemia [hazard ratio (HR) 0.75, 95% confidence interval (CI) 0.72-0.79], but a higher risk of the primary outcome (HR 1.10, 95% CI 1.06-1.14). Similar results were observed in patients with heart failure, after censoring when treatment decision was changed, and across pre-specified subgroups. CONCLUSIONS: Stopping MRA after an episode of hyperkalaemia was associated with reduced risk for recurrent hyperkalaemia, but higher risk of death or cardiovascular events. Recurrent hyperkalaemia was common in either strategy.

16.
Food Chem ; 366: 130559, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34289440

RESUMO

In order to realize rapid and non-destructive detection of hardness for maize kernels, a method for quantitative hardness measurement was proposed based on hyperspectral imaging technology. Firstly, the regression model of hardness and moisture content was established. Then, based on reflectance hyperspectral imaging at wavelengths within 399.75-1005.80 nm, the prediction model of the moisture content was studied by the partial least squares regression (PLSR) based on the characteristic wavelengths, which was selected through successive projection algorithm (SPA). Finally, the hardness prediction model was validated by combing the prediction model of moisture content with the regression model of hardness. The coefficient of determination (R2), the root mean square error (RMSE) the ratio of performance-to-deviation (RPD) and the ratio of error range (RER) of hardness prediction were 0.912, 17.76 MPa, 3.41 and 14, respectively. Therefore, this study provided a method for rapid and non-destructive detection of hardness of maize kernels.

17.
Eur Respir J ; 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34289974

RESUMO

The current pandemic of coronavirus disease 19 (COVID-19) has affected more than 160 million of individuals and caused millions of deaths worldwide at least in part due to the unclarified pathophysiology of this disease. Therefore, identifying the underlying molecular mechanisms of COVID-19 is critical to overcome this pandemic. Metabolites mirror the disease progression of an individual by acquiring extensive insights into the pathophysiological significance during disease progression. We provide a comprehensive view of metabolic characterization of sera from COVID-19 patients at all stages using untargeted and targeted metabolomic analysis. As compared with the healthy controls, we observed different alteration patterns of circulating metabolites from the mild, severe and recovery stages, in both discovery cohort and validation cohort, which suggest that metabolic reprogramming of glucose metabolism and urea cycle are potential pathological mechanisms for COVID-19 progression. Our findings suggest that targeting glucose metabolism and urea cycle may be a viable approach to fight against COVID-19 at various stages along the disease course.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34299945

RESUMO

With the COVID-19 vaccination widely implemented in most countries, propelled by the need to revive the tourism economy, there is a growing prospect for relieving the social distancing regulation and reopening borders in tourism-oriented countries and regions. This need incentivizes stakeholders to develop border control strategies that fully evaluate health risks if mandatory quarantines are lifted. In this study, we have employed a computational approach to investigate the contact tracing integrated policy in different border-reopening scenarios in Hong Kong, China. Explicitly, by reconstructing the COVID-19 transmission from historical data, specific scenarios with joint effects of digital contact tracing and other concurrent measures (i.e., controlling arrival population and community nonpharmacological interventions) are applied to forecast the future development of the pandemic. Built on a modified SEIR epidemic model with a 30% vaccination coverage, the results suggest that scenarios with digital contact tracing and quick isolation intervention can reduce the infectious population by 92.11% compared to those without contact tracing. By further restricting the inbound population with a 10,000 daily quota and applying moderate-to-strong community nonpharmacological interventions (NPIs), the average daily confirmed cases in the forecast period of 60 days can be well controlled at around 9 per day (95% CI: 7-12). Two main policy recommendations are drawn from the study. First, digital contact tracing would be an effective countermeasure for reducing local virus spread, especially when it is applied along with a moderate level of vaccination coverage. Second, implementing a daily quota on inbound travelers and restrictive community NPIs would further keep the local infection under control. This study offers scientific evidence and prospective guidance for developing and instituting plans to lift mandatory border control policies in preparing for the global economic recovery.

19.
Acta Biochim Biophys Sin (Shanghai) ; 53(7): 933-942, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34223883

RESUMO

The transgenic glyphosate-tolerant soybean MON87712 event was developed by the agrochemical and agricultural biotechnology company Monsanto (USA) and commercialized in 2013. Due to the absence of matrix-based and genomic DNA-positive reference material for MON87712, it is very difficult to detect and monitor this event. In this study, we developed a recombinant 760-bp linearized plasmid, including 150 bp of the soybean endogenous lectin gene and 610 bp of the exogenous BBX32 gene plus its 3' flanking sequence of MON87712 by In-Fusion cloning technology. In addition, a duplex real-time polymerase chain reaction for the detection of MON87712 and the soybean endogenous lectin gene was established. By using this method, we achieved specific and quantitative detection of MON87712 in 45 other kinds of crops, with a detection limit of 10 copies/µl. This method provides a new technical means for the accurate detection of transgenic soybean MON87712, as well as technical support for the supervision of agricultural transgenic organisms.

20.
Huan Jing Ke Xue ; 42(7): 3400-3404, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212666

RESUMO

The effect of ozone dosage on sludge settleability and biological nutrient removal performance in a sequencing batch reactor was investigated by inoculating the bulking sludge with the SVI of 280 mL·g-1 from a wastewater treatment plant in winter. The filamentous mycelium was interrupted, and the SVI was decreased to 125 mL·g-1 after ozone dosage with a low concentration of 0.085 g·g-1(O3/MLSS) for 20 days, which indicated the disappearance of the sludge bulking. The performance of nitrification and phosphorus removal efficiency was not affected obviously. However, the sludge settleability deteriorated with a high dosage of ozone, and the phosphorus removal efficiency was decreased to around 60%. Further study showed that PS/PN had a positive correlation with SVI with the correlation coefficient of 0.9381, which can be used to characterize sludge settleability. A low ozone dosage not only interrupted the filamentous mycelium, but it also affected the content and composition of the EPS, which led to improved settleability.


Assuntos
Ozônio , Esgotos , Reatores Biológicos , Nitrogênio , Nutrientes , Eliminação de Resíduos Líquidos
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