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1.
Am J Orthod Dentofacial Orthop ; 159(5): e389-e397, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33931225

RESUMO

INTRODUCTION: Determination of improvement in orthodontic treatment may depend on the measurement method used and the purpose. METHODS: Improvement after orthodontic treatment (from T1 to T2 [beginning to end of treatment]) was assessed 3 ways from a set of 98 patient records: (1) calculated by subtracting judges' assessments at T2 from T1 for records presented in random order, (2) judged as a holistic impression viewing T1 and T2 records side by side, and (3) determined from proxies (American Board of Orthodontics Discrepancy Index, the American Board of Orthodontics Objective Grading System, and the Peer Assessment Rating index). RESULTS: High levels of intramethod consistency were observed, with intraclass correlation coefficient clustering around an intraclass correlation coefficient of 0.900, and distributions were normal. Calculated and judged improvements correlated at r = 0.606. Calculated or judged improvements were correlated at a lower level with proxies. Calculated improvement was significantly associated with "challenge" (T1) scores and judged improvement associated with "results" (T2) scores. Common method bias was observed, with higher correlations among similar indexes than among indexes at the same time that used various methods. Relative to differences in Peer Assessment Rating scores, calculated improvement overestimated low scores and underestimated high ones. The same effect, but statistically greater, was observed using direct judgment of improvement. CONCLUSIONS: These findings are consistent with decision science and measurement theory. In some circumstances, such as third-party reimbursement and research, operationally defined measures of occlusion are appropriate. In practice, the determination of occlusion and improvement are best performed by judgment that naturally corrects for biases in proxies and incorporates background information.


Assuntos
Má Oclusão , Ortodontia , Assistência Odontológica , Oclusão Dentária , Humanos , Julgamento , Má Oclusão/terapia , Ortodontia Corretiva , Resultado do Tratamento
2.
Sci Total Environ ; 785: 147180, 2021 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-33932677

RESUMO

Many reviewers have applied bibliometric analysis to conduct research on heavy metals (HMs) in Chinese soil and found that risk management decisions were biased to a certain extent due to case distribution difference and uncertainty. The previous methodologies were optimized integrating further uncertainty control and case identification in this study. A solid database was built, which included 779 cases published from 2009 to 2020. Based on the data features, the weight method was used to objectively shield extreme cases and normalize the concentrations. We conducted fuzzy eco- and health risk models via a triangular fuzzy number, and identified the risks from Pb, Cd, As, and Hg as the priority control metals. However, the national HMs risk had complex spatial heterogeneity and significant uncertainty. Thus, an "integrated risk grade criterion (IRGC)" was coupled with the risk threshold concentrations for the eco- and health risks to classify the each case. The cases above the moderate IRGC grade for Cd or Hg accounted for approximately 50%, and were mainly in the west and north of China, respectively. The high-grade areas were mostly in the south of China, including the Xijiang-Pearl River Basin and the Yangtze River Basin. It was demonstrated that warning health risks were likely a local question and that the ecological risks from Hg and Cd were considerable across China. By reviewing and summarizing the text information, high grades of soil Cd, Pb, and As were frequently reported in the villages associated with the mining industry, and certain soil Cd near suburban industrial complexes also caused warning health risks. Finally, this study proposed priority control objects for hierarchical risk management, including the identified heavy metals, areas, and pilot cities from multi-spatial scales.

3.
Thorac Cancer ; 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33973725

RESUMO

BACKGROUND: Considering the high morbidity and mortality of lung cancer and the high incidence of pulmonary nodules, clearly distinguishing benign from malignant lung nodules at an early stage is of great significance. However, determining the kind of lung nodule which is more prone to lung cancer remains a problem worldwide. METHODS: A total of 480 patients with pulmonary nodule data were collected from Shandong, China. We assessed the clinical characteristics and computed tomography (CT) imaging features among pulmonary nodules in patients who had undergone video-assisted thoracoscopic surgery (VATS) lobectomy from 2013 to 2018. Preliminary selection of features was based on a statistical analysis using SPSS. We used WEKA to assess the machine learning models using its multiple algorithms and selected the best decision tree model using its optimization algorithm. RESULTS: The combination of decision tree and logistics regression optimized the decision tree without affecting its AUC. The decision tree structure showed that lobulation was the most important feature, followed by spiculation, vessel convergence sign, nodule type, satellite nodule, nodule size and age of patient. CONCLUSIONS: Our study shows that decision tree analyses can be applied to screen individuals for early lung cancer with CT. Our decision tree provides a new way to help clinicians establish a logical diagnosis by a stepwise progression method, but still needs to be validated for prospective trials in a larger patient population.

4.
J Nutr Biochem ; 94: 108645, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33838230

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a chronic disease affecting the health of many people worldwide. Previous studies have shown that dietary calcium supplementation may alleviate NAFLD, but the underlying mechanism is not clear. In this study investigating the effect of calcium on hepatic lipid metabolism, 8-week-old male C57BL/6J mice were divided into four groups (n = 6): (1) mice given a normal chow containing 0.5% calcium (CN0.5), (2) mice given a normal chow containing 1.2% calcium (CN1.2), (3) mice given a high-fat diet (HFD) containing 0.5% calcium (HFD0.5), and (4) mice fed a HFD containing 1.2% calcium (HFD1.2). To understand the underlying mechanism, cells were treated with oleic acid and palmitic acid to mimic the HFD conditions in vitro. The results showed that calcium alleviated the increase in triglyceride accumulation induced by oleic acid and/or palmitic acid in HepG2, AML12, and primary hepatocyte cells. Our data demonstrated that calcium supplementation alleviated HFD-induced hepatic steatosis through increased liver lipase activity, proving calcium is involved in the regulation of hepatic lipid metabolism. Moreover, calcium also increased the level of glycogen in the liver, and at the same time had the effect of reducing glycolysis and promoting glucose absorption. Calcium addition increased calcium levels in the mitochondria and cytoplasm. Taken together, we concluded that calcium supplementation could relieve HFD-induced hepatic steatosis by changing energy metabolism and lipase activity.

5.
Heart Surg Forum ; 24(2): E311-E316, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33798045

RESUMO

OBJECTIVES: To assess sex differences of clinical presentation and outcomes in propensity-matched patients with acute type A aortic dissection (AAAD). METHODS: We collected the clinical data of patients with AAAD from a single heart center between January 2009 and July 2014. After propensity score matching, we compared differences in clinical presentation and outcomes of patients with AAAD between men and women. RESULTS: There were 590 patients (295 men and 295 women) with AAAD through propensity matching on demographics and patients' history. We found that the presentation and diagnosis of AAAD often were more delayed in women. Severe signs of congestive heart failure (9.8% vs. 5.1%, P = 0.017), cardiac tamponade/shock (9.1% vs. 4.1%, P < 0.001), and periaortic hematoma (26.4% vs. 21.7%, P < 0.001) were more commonly presented in women. Surgery was more commonly performed in men than in women (95.4% (281/295) vs. 91.5% (270/295), P = 0.045), indicating the association of sex with surgical decision. To investigate the association of sex with outcomes after surgery, patients who underwent surgical treatment were re-matched (262 men and 262 women) by propensity score. Women suffered from greater in-hospital mortality than men (8.4% vs. 3.4%, P < 0.001). Postoperative complications of congestive heart failure (9.1% vs. 3.8%, P < 0.001), visceral ischemia (6.8% vs. 1.1%, P < 0.001), and limb ischemia (7.6% vs. 1.5%, P < 0.001) were more frequent in women. For women, prolonged operative time may increase in-hospital mortality, especially after 12 hours from the start of surgery (30.0% vs. 14.3%, P < 0.001). Kaplan-Meier survival analysis indicated worse late outcomes in women in the matched surgery group (log-rank P = 0.012). CONCLUSIONS: Our analysis provides new insights into sex differences in clinical presentation and outcomes of AAAD.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33834752

RESUMO

Continuous breakthroughs have been achieved in improving the efficiency of all-polymer solar cells (all-PSCs) using diimide-based polymer acceptors, and their easy-to-synthesize, low-cost, and high stability attributes make them potential candidates for use in commercial all-PSCs. However, their low light absorption coefficient, strong aggregation, and poor adaptability with high-efficient polymer donors still limit further improvements in the device performance. Here, we combine the advantages of fluorinated bithiophene and rhodanine dye molecules to create low-cost diimide-based polymer acceptors, PNDI-2FT-TR10 and PNDI-2FT-TR20, by random copolymerization for achieving highly efficient and stable all-PSCs. The synergistic effects of fluorine atoms and rhodanine dye molecules not only significantly improve the absorption coefficient but also enable enhanced miscibility and stability of the blend film. When blended with a PM6 donor, the PNDI-2FT-TR10-based device exhibits a notable power conversion efficiency (PCE) of 10.71% with a short-circuit current (JSC) of 17.32 mA cm-2. Note that both the PCE and JSC show outstanding values for diimide-based all-PSCs, and this is the first report on blending diimide-based polymer acceptors with the PM6 donor to achieve high-performance all-PSCs. Moreover, the favorable morphology of the active layer enables the device to have good thickness tolerance and thermal stability. The results demonstrate that the absorption coefficients, blend morphology, and photovoltaic properties of all-PSCs could be rationally optimized by a random copolymer.

7.
J Steroid Biochem Mol Biol ; 211: 105893, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33819629

RESUMO

During the periparturient transition period, negative energy balance (NEB) characterized by high concentrations of non-esterified fatty acids (NEFA) may cause fatty liver and ketosis in dairy cows. Previous studies have shown that the protein kinase R-like endoplasmic reticulum kinase (PERK) branch of the endoplasmic reticulum stress (ERS) response plays an important role in lipid metabolism in hepatocytes. This study, therefore, investigated the role of the PERK-branch in NEFA-induced fatty liver. Different concentrations of NEFA or GSK2656157 (a novel catalytic inhibitor of PERK) were used to treat hepatocytes isolated from calves. The NEFA treatment significantly increased the triacylglycerol (TG) content, the phosphorylation level of PERK and eukaryotic initiation factor 2α (eIF2α), and the abundance of glucose-regulated protein 78 (Grp78), C/EBP homologous protein (CHOP), sterol regulatory element-binding protein 1c (SREBP-1c), fatty acid synthase (FASN), peroxisome proliferator-activated receptor-α (PPARα), carnitine palmitoyltransferase 1A (CPT1A), apolipoprotein B (APOB), and the low-density lipoprotein receptor (LDLR). Compared with the 1.2 mM NEFA group, inhibition of PERK activity further increased the TG content in hepatocytes, the very-low-density lipoprotein (VLDL) content in the supernatant and the protein abundance of APOB while reducing the expression and nuclear levels of SREBP-1c and PPARα, as well as the expression of CPT1A and CPT2. In conclusion, the results showed that the NEFA-induced PERK-eIF2α signaling pathway promotes lipid synthesis, lipid oxidation, but inhibits the assembly and secretion of VLDL. Therefore, during the transition period, the activation of the PERK-eIF2α signaling pathway in the liver of dairy cows could defeat the acid-induced lipotoxicity and provide energy to alleviate NEB.

8.
Int J Biol Sci ; 17(6): 1486-1496, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33907512

RESUMO

The pandemic of Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome 2 coronavirus (SARS-CoV-2) continues to be a global health crisis. Fundamental studies at genome, transcriptome, proteome, and interactome levels have revealed many viral and host targets for therapeutic interventions. Hundreds of antibodies for treating COVID-19 have been developed at preclinical and clinical stages in the format of polyclonal antibodies, monoclonal antibodies, and cocktail antibodies. Four products, i.e., convalescent plasma, bamlanivimab, REGN-Cov2, and the cocktail of bamlanivimab and etesevimab have been authorized by the U.S. Food and Drug Administration (FDA) for emergency use. Hundreds of relevant clinical trials are ongoing worldwide. Therapeutic antibody therapies have been a very active and crucial part of COVID-19 treatment. In this review, we focus on the progress of therapeutic COVID-19 antibody development and application, discuss corresponding problems and challenges, suggesting new strategies and solutions.

9.
J Mater Chem B ; 9(16): 3509-3514, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33909733

RESUMO

Early glucose detection is important in both healthy people and diabetic patients. The glucose colorimetric detection techniques usually consist of multiple steps and their preparation processes are time consuming. In this work, we fabricate a GOX-hemin nanogel (GHN) that could be used for one-step colorimetry detection of glucose. The GHN was prepared by carrying out polymerization on the surface of GOX. Each GOX-hemin nanogel consists of a single GOX encapsulated with a thin polymer network containing hemin. The proximity of hemin to GOX facilitates two reactions, i.e. the oxidation of glucose catalysed by GOX to yield H2O2, and the subsequent 3,3',5,5'-tetramethylbenzidine (TMB) oxidation reaction catalysed by hemin to yield the blue colored product. These processes work in tandem, which greatly enhances the efficacy, sensitivity and stability of the detection system. The limit of detection in our system was determined to be as low as 4 µM. Furthermore, the glucose detection activity still maintained more than 70% even after being incubated at 55 °C for 30 minutes, or in 20% (v/v) aqueous solution of DMF, CH3CN or THF for 25 minutes at room temperature. It is anticipated that this work can provide a method for developing diverse functional materials based on proteins.

10.
Parasitol Res ; 120(5): 1627-1636, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33792812

RESUMO

Paragonimus proliferus, a lung fluke of the genus Paragonimus, was first reported in Yunnan province, China. P. proliferus can infect Sprague-Dawley (SD) rats and cause lung damage, but there is still no direct evidence of human infection. Until now, there has been a lack of studies on P. proliferus parasitism and development in mammalian lung tissue. The aim of this study was to perform transcriptomic profiling of P. proliferus at different developmental stages. SD rats were infected with P. proliferus metacercariae obtained from crabs; worms isolated from the lungs at different time points as well as metacercariae were subjected to whole transcriptome sequencing. Overall, 34,403 transcripts with the total length of 33,223,828 bp, average length of 965 bp, and N50 of 1833 bp were assembled. Comparative analysis indicated that P. proliferus, similar to other Paragonimus spp., expressed genes related to catabolism, whereas P. proliferus-specific transcripts were related to the maintenance of cellular redox homeostasis, sensitivity to bacteria, and immune response. Transcriptional dynamics analysis revealed that genes involved in the regulation of catabolism and apoptosis had stable expression over the P. proliferus life cycle, whereas those involved in development and immune response showed time-dependent changes. High expression of genes associated with immune response corresponded to that of genes regulating the sensitivity to bacteria and immune protection. We constructed a P. proliferus developmental model, including the development of the body, suckers, blood cells, reproductive and tracheal systems, lymph, skin, cartilage, and other tissues and organs, and an immune response model, which mainly involved T cells and macrophages. Our study provides a foundation for further research into the molecular biology and infection mechanism of P. proliferus.

11.
Psychophysiology ; 58(5): e13798, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33645762

RESUMO

Social comparison occurs when individuals evaluate themselves in comparison with others. Social distance can influence the effect of social comparison. Using event-related potentials, this study examined how social distance affects the time course of outcome processing when individuals compare themselves with others in terms of ability. Participants were asked to perform a dot estimation task with a friend and a stranger. The results showed the effect of social distance on the N1, feedback-related negativity (FRN), and P300, such that the N1 and P300 were greater for the outcome when pairing with the stranger than when pairing with the friend, whereas the FRN was more negative for the outcome when pairing with the friend than when pairing with the stranger, suggesting that participants allocated more attention resources to the stranger's outcome during the early, automatic (the N1) and later, controlled processing stage (the P300). In addition, the FRN was sensitive to the valence of both self- and other-outcomes, and the FRN valence effect of self-outcome was modulated by friends' outcomes but not by strangers' outcomes, indicating that at the semi-automatic processing stage, closer social distance increases the likelihood of individuals being affected by the comparison targets. These results suggest that when comparing with others in the ability dimension, social distance plays a different role in different stages of outcome processing. At the primary stage of outcome processing, individuals are more likely to compare with close others in the ability dimension.

12.
BMC Infect Dis ; 21(1): 302, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33765943

RESUMO

BACKGROUND: To explore population aging and the epidemic trend of pulmonary tuberculosis (PTB) in the elderly, and provide a basis for the prevention and control of pulmonary tuberculosis among the elderly. METHODS: We collected clinical information of 239,707 newly active PTB patients in Shandong Province from 2005 to 2017. We analyzed and compared the clinical characteristics, reported incidence and temporal trend of PTB among the elderly group (≥60 years) and the non-elderly group (< 60 years) through logistic model and Join-point regression model. RESULTS: Among the total PTB cases, 77,192(32.2%) were elderly. Compared with non-elderly patients, newly active elderly PTB patients account for a greater proportion of male cases (OR 1.688, 95% CI 1.656-1.722), rural population cases (OR 3.411, 95% CI 3.320-3.505) and bacteriologically confirmed PTB cases (OR 1.213, 95%CI 1.193-1.234). The annual reported incidence of total, elderly, pulmonary bacteriologically confirmed cases were 35.21, 68.84, 35.63 (per 100,000), respectively. The annual reported incidence of PTB in the whole population, the elderly group and the non-elderly group has shown a slow downward trend since 2008. The joinpoint regression model showed that the overall reported incidence of PTB in the elderly significantly decreased from 2007 to 2017 (APC = -5.3, P < 0.05). The reported incidence of bacteriologically confirmed PTB among elderly patients declined rapidly from 2005 to 2014(2005-2010 APC = -7.2%, P < 0.05; 2010-2014 APC = -22.6%, P < 0.05; 2014-2017 APC = -9.0%, P = 0.1). The reported incidence of clinically diagnosed PTB among elderly patients from 2005 to 2017 (11.48-38.42/100,000) increased by about 235%. It rose significantly from 2007 to 2014 (APC = 9.4, P<0.05). CONCLUSIONS: Compared with the non-elderly population, the reported incidence of PTB in the elderly population is higher. The main burden of PTB will shift to the elderly, men, rural population, and clinically diagnosed patients. With the intensification of aging, more researches on elderly PTB prevention and treatment will facilitate the realization of the global tuberculosis (TB) control targets.


Assuntos
Envelhecimento , Tuberculose Pulmonar/epidemiologia , Idoso , China/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , População Rural , Tuberculose Pulmonar/diagnóstico , População Urbana
13.
EMBO Rep ; 22(4): e51606, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33655635

RESUMO

Reduction of mitochondrial membrane potential (Δψm ) is a hallmark of mitochondrial dysfunction. It activates adaptive responses in organisms from yeast to human to rewire metabolism, remove depolarized mitochondria, and degrade unimported precursor proteins. It remains unclear how cells maintain Δψm , which is critical for maintaining iron-sulfur cluster (ISC) synthesis, an indispensable function of mitochondria. Here, we show that yeast oxidative phosphorylation mutants deficient in complex III, IV, V, and mtDNA, respectively, exhibit activated stress responses and progressive reduction of Δψm . Extensive omics analyses of these mutants show that these mutants progressively activate adaptive responses, including transcriptional downregulation of ATP synthase inhibitor Inh1 and OXPHOS subunits, Puf3-mediated upregulation of import receptor Mia40 and global mitochondrial biogenesis, Snf1/AMPK-mediated upregulation of glycolysis and repression of ribosome biogenesis, and transcriptional upregulation of cytoplasmic chaperones. These adaptations disinhibit mitochondrial ATP hydrolysis, remodel mitochondrial proteome, and optimize ATP supply to mitochondria to convergently maintain Δψm , ISC biosynthesis, and cell proliferation.

14.
Mol Cell Proteomics ; 20: 100068, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33676000

RESUMO

Signet ring cell carcinoma (SRCC) is a histological subtype of gastric cancer with distinct features in multiple aspects compared with adenocarcinomas (ACs). The lack of a systematic molecular overview of this disease has led to slow progress in its clinical practice. In the present proteomics study, gastric tissues were collected from tumors and adjacent tissues, including 14 SRCCs and 34 ACs, and laser capture microdissection (LCM) was employed to eradicate the cellular heterogeneity of the tissues. The proteomes of tissues were profiled by data-independent acquisition (DIA) mass spectrometry (MS). Based on the over 6000 proteins quantified, univariate analysis and pathway enrichment revealed that some proteins and pathways demonstrated differences between SRCC and ACs. Importantly, the upregulation of a majority of complement-related proteins was notable for SRCC but not for ACs. A hypothesis, based on the proteomics evidence, was proposed that the complement cascade was evoked in the SRCC microenvironment upon infiltration, and the SRCC cells survived the complement cytotoxicity by secreting endogenous negative regulators. Moreover, an attempt was made to establish appropriate cell models for gastric SRCC through proteomic comparison of the 15 gastric cell lines and gastric tumors. The predictions of a supervised classifier suggested that none of these gastric cell lines qualified to mimic SRCC. This study discovered that the complement cascade is activated at a higher level in gastric SRCC than in ACs.

15.
J Reprod Immunol ; 145: 103312, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33770728

RESUMO

Toxoplasma gondii (T. gondii) is a ubiquitous intracellular protozoan parasite that causes adverse pregnancy outcomes. Innate lymphoid cells (ILCs) are critical mediators of mucosal immunity, and have been reported to play an important role in uterine vascular adaptation for successful pregnancy. However, the specific role of ILCs in T. gondii-infection-induced adverse pregnancy outcomes remains elusive. In the present study, we found that T. gondii infection caused the imbalance of uterine ILC cells (uILCs). It was characterized by substantially lower expression of the transcription factor GATA-3 and RORγt and higher expression of T-bet in uILCs. Consistent with the transcription factor changes, uILCs from T. gondii-infected mice produced much less IL-5 and IL-17 and substantially more IFN-γ and TNF-α than did uILCs from uninfected mice. Notably, IL-12, IL-18, and their receptors were increased in the uterus of T. gondii-infected mice. In vitro experiments showed that IL-12 and IL-18 treatment reduced the percentages of uILC2 and uILC3 and increased the percentages of uILC1. Conclusion, our data suggest that alterations in uILC composition may disrupt the balance of immune microenvironment after T. gondii infection and contribute to the adverse pregnancy outcomes caused by T. gondii infection.

16.
Vaccines (Basel) ; 9(3)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33671003

RESUMO

The mean age of lung transplant recipients has significantly increased in recent decades. Elderly recipients have a higher risk of developing herpes zoster (HZ), and they have in general a worse response to vaccination than younger persons do. We investigated the relationship between the humoral and cellular immune response to a live-attenuated HZ vaccine (Zostavax®, Merck Sharp and Dohme) and the frequencies of T and B cell subsets, especially aged cell subsets (CD28-T cells and age associated B cells, ABCs). In total, 37 patients awaiting lung transplantation received one dose of Zostavax®, and peripheral blood was collected before and within 6 months after vaccination. We observed a robust immune response after vaccination. The frequencies of CD28-T cells before vaccination had no impact on the subsequent immune response to HZ vaccination. However, a higher frequency of ABCs before vaccination correlated with a lower immune response especially regarding the cellular immune response. Cytomegalovirus seropositivity was associated with increased frequencies of CD28-T cells but not with frequencies of ABCs in the patients. In conclusion, increased levels of ABCs might disturb the cellular immune response to HZ vaccination, which could lower the efficacy of such vaccination in elderly transplant recipients.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33517651

RESUMO

Here, we put forward an effective strategy to regulate the interface structure of carbon nanotubes/polyaniline (CNTs/PANI) composite films and improve their thermoelectric (TE) properties by sequential dedoping-redoping treatment. Dedoping induces conductive resistance-undoped PANI to enhance the energy barrier between CNTs and PANI, leading to a greatly increased Seebeck coefficient and deteriorated conductivity. Subsequently, upon the redoping process, the electrical conductivity is dramatically improved owing to the generated conductive PANI chains, while Seebeck coefficient is maintained at 90% of the dedoped composites. This yields a significantly improved power factor of 407 µW m-1 K-2 from the as-prepared composites (234 µW m-1 K-2), which is the highest value among those of all the reported CNTs/PANI composites. The outstanding TE performanceis probably ascribed to the multiple interface structure of the PANI composite generated from incomplete dedoping and redoping processes, contributing to the enhanced carrier-filtering effect to retain a relatively high Seebeck coefficient and efficient charge transport to improve conductivity. Furthermore, the flexible TE device generates a high power of 1.5 µW at ΔT = 50 K, demonstrating the applicability of this composite for energy-harvesting electronic devices.

18.
Artigo em Inglês | MEDLINE | ID: mdl-33539705

RESUMO

Metal-support interaction strongly influences the catalytic properties of metal-based catalysts. Here, titanium nitride (TiN) nanospheres are shown to be an outstanding support, for tuning the electronic property of platinum (Pt) nanoparticles and adjusting the morphology of indium sulfide (In2S3) active components, forming flower-like core-shell nanostructures (TiN-Pt@In2S3). The strong metal-support interaction between Pt and TiN through the formation of Pt-Ti bonds favors the migration of charge carriers and leads to the easy reducibility of TiN-Pt, thus improving the photocatalytic atom efficiency of Pt. The TiN-Pt@In2S3 composite shows reduction of Pt loading by 70% compared to the optimal Pt-based system. In addition, the optimal TiN-Pt@In2S3 composite exhibits a H2 evolution rate 4 times that of a Pt reference. This increase outperforms all other supports reported thus far.

19.
J Ethnopharmacol ; 273: 113839, 2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-33476713

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Eighteen Incompatible Medicaments (EIM) belongs to the category of incompatibility of Traditional Chinese medicine (TCM). This theory forbids concomitant using any one of the eighteen herbal pairs such as Radix Glycyrrhizae (RG)-Radix Euphorbiae Pekinensis (REP), Radix Aconiti-Bulbus Fritiliariae Cirrhosae, and Radix et Rhizoma Veratri Nigri-Radix Ginseng. Concomitant using RG and REP could result in more serious adverse effects on major organs such as kidney, heart, and liver. AIM OF THE STUDY: To investigate the effects of RG-REP decoctions on gut microbiota and short-chain fatty acids (SCFAs) for the purpose of elucidating the mechanism of RG-REP incompatibility. MATERIALS AND METHODS: Six groups of male SD rats were intragastrically administrated with distilled water, RG decoction, REP decoction, 1:1 RG-REP decoction, 2:1 RG-REP decoction and 3:1 RG-REP decoction, respectively, twice daily for 30 consecutive days, and the feces of each rat was separately sampled for gut microbiota analysis and SCFAs assay. 16S rDNA sequencing was employed to comparatively investigate the structure and abundance of intestinal bacteria in rat feces. Gas chromatography (GC) was used to quantitatively determine the contents of SCFAs in rat feces and in vitro samples. The correlation between bacteria and the production of SCFAs was analyzed by Spearman correlation analysis. An in vitro model of human intestinal bacteria was also constructed to simulate and validate the in vivo experiment. RESULTS: The contents of butyric acid in both rat feces and in vitro samples decreased in RG-REP groups. The general structure of gut microbiota in RG-REP groups was not significantly different from that in control group. However, RG alone increased the abundance of Lactobacillus while this effect was counteracted by concomitant using with REP. REP alone decreased the abundance of two interrelated species, Akkermansia and Butyricimonas, and this effect was strengthened by concomitant using REP with RG in the ratio of 1:1. In comparison with REP alone, RG-REP combination also significantly increased the abundance of Streptococcus and Prevotella. CONCLUSION: The incompatibility of RG-REP combination is associated with its negative effect against probiotic bacteria and positive effect on conditional pathogenic bacteria as well as its inhibition on butyric acid production.

20.
Sci Total Environ ; 768: 144515, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33453542

RESUMO

Dinoflagellate blooming periods are paradoxically characterized by high biomass growth rate and low ambient dissolved CO2 and inorganic nutrients, however, the underlying mechanisms linking cell growth and nutrient acquisition are poorly understood. Here, we compared metaproteomes of non-bloom, mid-blooming and late-blooming cells of a marine dinoflagellate Prorocentrum donghaiense. Cell division, metabolism of carbon, nitrogen, phosphorus, lipid, porphyrin and chlorophyll were more active in blooming cells than in non-bloom cells. Up-regulation of carbonic anhydrase, ribulose-1,5-bisphosphate carboxylase/oxygenase II, and C4-cycle proteins enhanced CO2 assimilation of P. donghaiense. Proteins participating in external organic nutrient acquisition and conversion, such as transporters for fatty acids, peptides and amino acids, external- and internal-phosphomonoester hydrolase, and diverse peptidases and amino acid transaminases, exhibited higher expression in blooming cells relative to non-bloom cells. Interestingly, dissolved organic nitrogen (DON) such as urea and aspartate significantly down-regulated expression and activity of carbon assimilation proteins except for RuBisCO form II, suggesting that DON provided sufficient carbon source which reduced the need to concentrate internal CO2. This study demonstrates that coupling of efficient CO2 assimilation with DON utilization are essential for bloom maintenance of P. donghaiense, and future efforts should be devoted to dissolved organic nutrients for prevention and management of dinoflagelllate blooms.


Assuntos
Dinoflagelados , Dióxido de Carbono , Proliferação Nociva de Algas , Nutrientes , Fósforo
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