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1.
West J Nurs Res ; : 193945920916750, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32406791

RESUMO

This study aims to systematically evaluate the efficacy of mindfulness-based intervention (MBI) in improving mental health and quality of life for people with dementia. Comprehensive literature search was performed using the PubMed, EMBASE, Web of Science, Cochrane Library, and CINAHL databases from their inception till June 26, 2019. In total, nine articles met the eligibility criteria and were included. The results of the meta-analysis showed a statistically significant decrease in depressive symptoms (SMD = -0.39, 95% CI: - 0.62 to - 0.15), in people with dementia who were treated with MBI. However, there were no significant improvements in anxiety, stress, or quality of life. These findings suggest that MBI is a promising alternative to conventional interventions in the treatment of depression among dementia patients and warrant further study.

2.
J Mater Chem B ; 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32373898

RESUMO

Decellularized cartilage scaffold (DCS) is an emerging substitute for cartilage defect application. However, it is hard to preserve an intact structure of such scaffolds derived from terrestrial animals, because of their dense and compact constitution. In contrast, squid (Dosidicus gigas) cranial cartilage, which possesses a relatively loose structure, could be easily decellularized using mild conditions and it retains the original microstructures of extracellular matrix (ECM). Herein, decellularized squid cranial cartilage scaffold (DSCS) was fabricated successfully after substantially removing the cells, which contained abundant ECM components (proteoglycans and type II collagen). Microscopic structure results showed that the DSCS possesses a relatively smooth and dense surface with a favorable interconnected inner porous structure for cell growth. DSCS exhibited excellent biomechanics and hydrophilicity. In vitro experiments indicated that the scaffold extracts were not toxic to cells, and were amenable to chondrocyte migration. Meanwhile, chondrocytes seeded in DSCS could maintain a favorable viability and present a spreading morphology. Furthermore, the in vivo experiments revealed that both cell-free scaffold and cell-laden scaffold exert promotive effects for the regeneration of cartilage in a full-thickness rabbit cartilage defect model. Taken together, these results suggested that DSCS presents a novel and promising cell-free therapeutic choice for cartilage tissue engineering.

3.
Placenta ; 93: 26-33, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32250736

RESUMO

INTRODUCTION: Accumulating evidences have suggested a crucial role of epigenetics in the initiation and progression of pre-eclampsia (PE). Here, we studied the expression of the metalloproteinase ADAMTS7 and the methylation level of its promoter in PE placentas and investigated ADAMTS7 role in the pathogenesis of PE. METHODS: We first explored ADAMTS7 expression in PE and normal placentas by reverse transcription quantitative PCR (RT-qPCR), western blot, and immunohistochemistry. Methylation specific PCR (MSP) and bisulfite sequencing PCR (BSP) were performed to evaluate the methylation status of ADAMTS7 promoter. Treatment with 5'-Aza was used to induce demethylation and thereby to explore the direct relationship between promoter methylation and ADAMTS7 expression. CCK8 assay, colony formation assay, and trans-well assay were conducted to assess the viability, migration, and invasion of HTR-8/SVneo and JEG-3 cells. RESULTS: Our results showed that ADAMTS7 expression was upregulated in PE placentas. Methylation analysis revealed a hypomethylated status of ADAMTS7 promoter regions in PE placenta tissues. Besides, demethylation induced by 5'-Aza directly restored ADAMTS7 expression in trophoblast cells. Finally, overexpression of ADAMTS7 inhibited viability, migration, and invasion of HTR-8/SVneo and JEG-3 cells, while silence of ADAMTS7 by RNA interference reciprocally facilitated cell viability, migration and invasion in vitro. DISCUSSION: Upregulation of ADAMTS7 by promoter hypomethylation in placenta might contribute to the etiology of PE via suppressing cell functions of trophoblasts.

4.
Physiol Plant ; 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32333383

RESUMO

Owing to the potential health benefits, anthocyanin-rich teas (Camellia sinensis) have attracted interest over the past decade. Previously, we developed the cultivar 'Ziyan,' which has dark-purple leaves because of the accumulation of a high amount of anthocyanins. In this study, we performed a genetic analysis of this anthocyanin-rich tea cultivar and 176 of its naturally pollinated offspring. For two consecutive years, we quantified the anthocyanins and catechins of 'Ziyan' and the offspring population. While >60% of the offspring accumulated less than half of the amount of anthocyanins of 'Ziyan,' 17 (2018) and 15 (2019) individuals exceeded 'Ziyan' in anthocyanin content. A negative correlation between anthocyanin and total catechin content (r = -0.59, P < 0.001) was observed. The population was genotyped with 131 SSR markers spanning all linkage groups of the C. sinensis genome. Kruskal-Wallis tests identified 10 markers significantly associated with anthocyanins, catechins and their ratios in both years. Quantitative trait locus (QTL) analyses using the interval mapping method detected 13 QTLs, suggesting the dark-purple trait of 'Ziyan' is because of the pyramiding of anthocyanin-promoting alleles on at least five linkage groups. Two genetic loci reversely related to anthocyanin and total catechin contents were identified. This study provides valuable information for genetic improvement of purple tea cultivars and for fine-mapping related genes.

5.
J Biomed Mater Res A ; 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32323472

RESUMO

This study evaluated the effect of thermosensitive hydroxybutyl chitosan (HBC) hydrogel loaded with human platelet lysate (hPL) on skin wound healing in rats. hPLs were generated by freeze-thaw method of platelet-rich plasma from healthy donors. Successful grafting of hydroxybutyl group to chitosan molecular chain to obtain HBC hydrogel was confirmed by Fourier-transform infrared spectroscopy. HBC/hPL was prepared by combining 10% (vol/vol) hPL with HBC solution. Surface morphologies were determined by Scanning Electron Microscopy, rheological properties were measured by rheometer, and sustained release of factors from HBC/hPL was measured by enzyme-linked immunoassay. We evaluated the in vitro effect of HBC/hPL on human umbilical cord vein endothelial cell (HUVEC) proliferation, migration, and tube formation. The effect of growth factors released from HBC/hPL in promoting skin wound healing was evaluated by gross observation, histology, immunohistochemistry, and immunofluorescence in vivo. Rheological analyses indicated the gelation temperatures of HBC and HBC/hPL were 17 and 14°C, respectively. ELISA showed sustained release of human platelet-derived growth factor, basic fibroblast growth factor, and transforming growth factor-ß1 from HBC/hPL hydrogel. In vitro studies revealed HBC/hPL promoted greater levels of HUVECs proliferation, migration, and tube formation than the HBC and control groups. In vivo studies showed better wound healing, greater amounts of newly formed collagen, as well as neovascular and neo-epidermis markers in the wound site of HBC/hPL-treated group compared to the HBC and control groups. HBC/hPL is a promising potential therapeutic agent for promoting skin wound healing via the sustained release of growth factors.

6.
Eur J Obstet Gynecol Reprod Biol ; 248: 211-221, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32240894

RESUMO

OBJECTIVE: Pre-eclampsia (PE) is a common multi-systemic disease, and the effect of cytokines on PE is not clear. The purpose of this meta-analysis was to evaluate the circulating levels of interferon gamma (IFN-γ), interleukin (IL)-1, IL-17 and IL-22 in patients with PE. STUDY DESIGN: Relevant studies were identified after a preliminary investigation of studies published up to May 2019 using PubMed and Embase. In this study, all 27 included articles underwent quality rating, with a total of 495 patients with PE and 557 controls. Among them, eight papers and 932 subjects contributed to the meta-analysis of IFN-γ, and six papers and 343 subjects contributed to the meta-analysis of IL-17. Based on the inclusion and exclusion criteria, the retrieved papers were screened and evaluated independently. Relevant data for IFN-γ and IL-17 were extracted for meta-analysis and subgroup analysis, and the stability of the results was evaluated by sensitivity analysis. At the same time, a systematic evaluation was carried out for IL-1 and IL-22 with a small number of included papers. RESULTS: Several papers included in the systematic review showed that the circulating levels of IL-22 were higher in patients with severe PE than in controls, while IL-1 levels did not differ significantly between the two groups. The meta-analysis showed that patients with PE had higher circulating levels of IFN-γ than controls [standardized mean difference (SMD) 1.45, 95 % confidence interval (CI) 0.56-2.34]. There was no evidence of a difference in the circulating levels of IL-17 between patients with PE and controls (SMD 0.53, 95 %CI -0.43 to 1.48). CONCLUSION: This meta-analysis suggested that changes in circulating levels of IFN-γ might be associated with PE.

7.
Nat Commun ; 11(1): 1599, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32221300

RESUMO

Surface charge density is the key factor for developing high performance triboelectric nanogenerators (TENG). The previously invented charge excitation TENG provides a most efficient way to achieve maximum charge output of a TENG device. Herein, criteria to quantitatively evaluate the contact efficiency and air breakdown model on charge excitation TENG are established to enhance and evaluate charge density. The theoretical results are further verified by systematic experiments. A high average charge density up to 2.38 mC m-2 is achieved using the 4 µm PEI film and homemade carbon/silicone gel electrode in ambient atmosphere with 5% relative humidity. This work also reveals the actual charge density (over 4.0 mC m-2) in a TENG electrode based on quantified surface micro-contact efficiency and provides a prospective technical approach to improve the charge density, which could push the output performance of TENG to a new horizon.

8.
Nephron ; : 1-6, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32182617

RESUMO

AIMS: This study aimed to investigate the association of single nucleotide polymorphisms (SNPs) within vascular endothelial growth factor (VEGF) gene and additional gene-environment interaction with renal cell carcinoma (RCC) risk. METHODS: PCR-restriction fragment length polymorphism was performed to detect SNPs. Hardy-Weinberg equilibrium and allele frequencies in cases and controls were calculated using SNPStats (http://bioinfo.iconcologia.net/SNPstats). Generalized multifactor dimensionality reduction (GMDR) was used to screen the best interaction combination among 4 SNPs, smoking, and alcohol drinking. Logistic regression was performed to investigate the association between 4 SNPs within VEGF gene, additional gene-smoking interaction, and RCC risk. RESULTS: RCC risk was significantly higher in carriers with the T allele of rs833061 within VEGF gene than those with CC genotype (CT+TT vs. CC) {adjusted odds ratio (OR) (95% confidence interval [CI]) = 1.71 (1.17-2.32), p = 0.002} and higher in carriers with the A allele of rs699947 within VEGF gene than those with GG genotype (GA+AA vs. GG) (adjusted OR [95% CI] = 1.64 [1.27-2.10], p < 0.001). GMDR analysis indicated a significant 2-locus model (p = 0.0010) involving rs833061 and smoking. The cross-validation consistency of the 2-locus model was 10/10, and the testing accuracy was 60.72%. Current smokers with rs833061-CT+TT genotype had the highest RCC risk, compared to never smokers with rs833061-CC genotype within VEGF gene (OR [95% CI] = 3.02 [1.84-4.23], p < 0.001). CONCLUSIONS: We found that the T allele of rs833061 and the A allele of rs699947 within VEGF gene, and the interaction between rs833061 and smoking were all associated with increased RCC risk.

9.
Environ Sci Pollut Res Int ; 27(15): 18773-18783, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32207003

RESUMO

To improve the electrocatalytic efficiency of the cathode and provide a wider pH range in the electro-Fenton process, N-doped multi-walled carbon nanotubes (NCNTs) and ferrous ion complexed with carboxylated carbon nanotubes (CNT-COOFe2+) were used to fabricate the diffusion layer and catalyst layer of a membrane cathode, respectively. The morphology, structure, and composition of CNT-COOFe2+ were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The oxygen reduction performance of NCNT was evaluated using cyclic voltammetry (CV) and the rotating disk electrode technique (RDE). In addition, a potential application of the cathode in sequential electro-Fenton degradation of p-nitrophenol (p-NP) was investigated. The results revealed that iron was successfully doped on the carboxylated carbon nanotubes in ionic complexation form and the content of iron atoms in CNT-COOFe2+ was 2.65%. Furthermore, the defects on the tube walls provided more reactive sites for the electro-Fenton process. A combination of CV and RDE data indicated that NCNT had better electrocatalytic H2O2 generation activity with a more positive onset potential and higher cathodic peak current response than CNT. A p-NP removal rate of 96.04% was achieved within 120 min, and a mineralization efficiency of 80.26% was obtained at 180 min in the sequential electro-Fenton process at a cathodic potential of - 0.7 V vs SCE and neutral pH. The activity of the used cathode was restored simply through electro-reduction at - 1.0 V vs SCE, and a p-NP removal rate of more than 70% was obtained at 60 min after six regeneration cycles.

10.
ACS Nano ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32049482

RESUMO

Vibrations in the environment are usually distributed over a wide frequency spectrum in multiple directions and a weaker amplitude, which makes most of the current vibrational energy collectors limited in practical environmental applications. Herein, a triboelectric-electromagnetic hybridized nanogenerator (TEHG) for low-frequency random microvibrational energy harvesting in all directions and a wide working bandwidth is fabricated. The output peak power of a triboelectric nanogenerator (TENG) up to 3.65 mW is realized (θ = 0.4 rad, f = 1 Hz). In addition, a real self-powered seawater splitting system and electrochemical cathodic protection system are fabricated, directly converting blue energy to hydrogen energy, and the ships can achieve self-protection against corrosion. Furthermore, relying on the linear relationship between the number of peaks and the amplitude of vibration, a highly sensitive self-powered vibration amplitude sensor system based on LabVIEW software is achieved, which can be used as an amplitude detection of bridges and earthquake monitoring, etc. This work is an important development for harvesting low-frequency random multiple direction microvibrational energy over a wide working bandwidth and the bright future of blue energy. In addition, it has been successfully applied to the power supply of portable electronic equipment, environmental monitors, and self-powered systems.

11.
J Cell Mol Med ; 24(7): 4183-4193, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32090454

RESUMO

Osteoarthritis (OA), which is principally featured by progressive joint metabolic imbalance and subsequent degeneration of articular cartilage, is a common chronic joint disease. Arctigenin (ATG), a dietary phyto-oestrogen, has been described to have potent anti-inflammatory effects. Nevertheless, its protective effects on OA have not been clearly established. The target of our following study is to evaluate the protective effects of ATG on IL-1ß-induced human OA chondrocytes and mouse OA model. Our results revealed that the ATG pre-treatment effectively decreases the level of pro-inflammatory mediators, such as prostaglandin E2 (PGE2), nitrous oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), IL-6 and tumour necrosis factor alpha (TNF-α) in IL-1ß-induced human chondrocytes. In addition, ATG protects against the degradation of extracellular matrix (ECM) under the stimulation of IL-1ß and the possible mechanism might be connected with the inactivation of phosphatidylinositol-3-kinase (PI3K)/Akt/nuclear factor-kappa B (NF-κB) axis. Furthermore, a powerful binding capacity between ATG and PI3K was also uncovered in our molecular docking research. Meanwhile, ATG may act as a protector on the mouse OA model. Collectively, all these findings suggest that ATG could be utilized as a promising therapeutic agent for the treatment of OA.

12.
J Cell Mol Med ; 24(6): 3701-3711, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32068951

RESUMO

As a chronic musculoskeletal degeneration disease, intervertebral disc degeneration (IVDD) has been identified as a crucial cause for low back pain. This condition has a prevalence of 80% among adults without effective preventative therapy. Procyanidin B3 (Pro-B3) is a procyanidin dimer, which is widely present in the human diet and has multiple functions, such as preventing inflammation. But the inhibiting effect of Pro-B3 in IVDD development is still no known. Thus, our study aimed to demonstrate the therapeutical effect of Pro-B3 in IVDD and explain the underlying mechanism. In vitro studies, human nucleus pulposus (NP) cells were isolated and exposed in lipopolysaccharide (LPS) to simulate IVDD development. Pro-B3 pre-treatment inhibited LPS-induced production of inflammation correlated factors such as tumour necrosis factor α (TNF-α), interleukin-6 (IL-6), prostaglandin E2 (PGE2) and Nitric oxide (NO). On the other hand, LPS-medicated extracellular matrix (ECM) breakdown was blocked in Pro-B3 treated NP cells. Additionally, Pro-B3 treatment blocked the activation of NF-κB/toll-like receptor 4 pathway in LPS-exposed NP cells. Mechanistically, Pro-B3 could occupy MD-2's hydrophobic pocket exhibiting high affinity for LPS to intervene LPS/TLR4/MD-2 complex formation. In vivo, Pro-B3 treatment prevented the loss of gelatin NP cells and structural damage of annulus fibrosus in rat IVDD model. In brief, Pro-B3 is considered to be a treatment agent for IVDD.

13.
Endokrynol Pol ; 71(2): 153-159, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32096550

RESUMO

INTRODUCTION: Thyroid dysgenesis (TD) is the main cause of congenital hypothyroidism (CH), affecting nearly 1 in 2000-3000 newborns worldwide, as the most common neonatal endocrine disorder. Paired box gene 8 (PAX8), expressed during all stages of thyroid follicular cell, plays a key role in thyroid morphogenesis by a complex regulatory network. In conclusion, the genetic mechanism of PAX8 mutant in TD is still ambiguous; therefore, further research is needed. MATERIAL AND METHODS: Blood samples were collected from 289 TD patients in Shandong Province, China. Genomic DNA was extracted from peripheral blood. All the exons of PAX8 along with their exon-intro boundaries were amplified by PCR and analysed by Sanger sequencing. RESULTS: We identified three novel PAX8 nonsense mutations in three patients by sequence analysis of PAX8: Patient 1 (c.285C>G, p.Tyr95Ter), Patient 2 (c.747T>G, p.Tyr249Ter), and Patient 3 (c.786C>A, p.Tyr262Ter). All the three patients carrying PAX8 variants had obvious clinical phenotypes of thyroid anomaly, such as hypoplasia and athyreosis. CONCLUSION: We conducted the largest worldwide PAX8 mutation screening so far in TD patients. Three presumably pathogenic PAX8 mutations were detected in 289 TD cases for the first time, showing the mutation rate of PAX8 is 1.04% in Chinese TD patients. In addition, our study expands the gene mutation spectrum of TD.

14.
Chemosphere ; 248: 125957, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32006829

RESUMO

This study reports on the propranolol (PRO) degradation performance and product toxicity of an ultraviolet light-emitting diode (UV-LED)/chlorine process. The effects of experimental parameters including solution pH, chlorine dosage, and water matrix constituents on PRO removal were evaluated. Up to 94.5% of PRO could be eliminated within 15 min at a PRO-to-chlorine molar ratio of 1:4. The overall removal efficiency of PRO was non-pH dependent in the range of 5-9, while the initial rate was accelerated under alkaline conditions. The presence of Cl-/HCO3- had little influence on the PRO degradation, whereas either humic acid or NO3- had an obvious inhibitory effect. Radical scavenger experiments showed that both HO and Cl primarily contributed to the PRO degradation, and electron paramagnetic resonance data demonstrated the generation of 1O2. The transformation of PRO during this process led to five detected products, which exhibited a higher acute toxicity than the parent compound according to the bright luminescent bacillus T3 method. It is worth mentioning that under the same ultraviolet illumination intensity, the degradation of PRO under UV-LED/chlorine gave a better performance than UV254/chlorine, but the EEO of the former is obviously higher than the latter. So further research is required on improving the electric current to photon conversion efficiency for UV-LED. Additionally, the UV-LED/chlorine system was effective in the degradation of other drugs including sulfamethoxazole, oxytetracycline hydrochloride, and gatifloxacin, suggesting the possible application of the UV-LED/chlorine process for the removal of pharmaceuticals during wastewater treatment.


Assuntos
Propranolol/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Cloro/química , Substâncias Húmicas , Cinética , Oxirredução , Propranolol/toxicidade , Raios Ultravioleta , Águas Residuárias , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
15.
Environ Pollut ; 261: 114129, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32045792

RESUMO

Glyphosate is the most popular herbicide used worldwide. This study aimed to investigate the adverse effects of glyphosate on the small intestine and gut microbiota in rats. The rats were gavaged with 0, 5, 50, and 500 mg/kg of body weight glyphosate for 35 continuous days. The different segments of the small intestine were sampled to measure indicators of oxidative stress, ion concentrations and inflammatory responses, and fresh feces were collected for microbiota analysis. The results showed that glyphosate exposure decreased the ratio of villus height to crypt depth in the duodenum and jejunum. Decreased activity of antioxidant enzymes (T-SOD, GSH, GSH-Px) and elevated MDA content were observed in different segments of the small intestine. Furthermore, the concentrations of Fe, Cu, Zn and Mg were significantly decreased or increased. In addition, the mRNA expression levels of IL-1ß, IL-6, TNF-α, MAPK3, NF-κB, and Caspase-3 were increased after glyphosate exposure. The 16 S rRNA gene sequencing results indicated that glyphosate exposure significantly increased α-diversity and altered bacterial composition. Glyphosate exposure significantly decreased the relative abundance of the phylum Firmicutes and the genus Lactobacillus, but several potentially pathogenic bacteria were enriched. In conclusion, this study provides important insight to reveal the negative influence of glyphosate exposure on the small intestine, and the altered microbial composition may play a vital role in the process.

16.
Reprod Sci ; 27(2): 468-476, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32016800

RESUMO

Pre-eclampsia (PE) is a serious pregnancy complication defined as hypertension combined with proteinuria. Previous report has indicated that the expression of connective tissue growth factor (CTGF) is upregulated in PE placentas. In this study, we aim to investigate the potential association between the methylation of the CTGF promoter and PE. The methylation status of CTGF promoter was assessed by methylation-specific PCR and the expression of CTGF was analyzed by real-time quantitative PCR and immunohistochemistry staining, in placental samples from PE patients and normal pregnant women. The methylation level of the CTGF promoter was also analyzed in peripheral blood DNA samples from 90 PE patients and 94 normal pregnant women and further confirmed by methylation-sensitive restriction enzyme digestion combined with real-time PCR. We found a decreased methylation rate of CTGF promoter in PE placentas compared with normal control. In addition, the frequency of hemimethylated (UM) promoter of CTGF in peripheral blood was significantly lower in the PE group (P = 0.019), while the frequency of overall methylated (MU + MM) promoter of CTGF in peripheral blood was lower (borderline significance P = 0.043) in the PE group. The percentage of methylated CpG in CTGF promoter was 30% lower in maternal blood of PE subjects than in controls. Moreover, the lower methylation frequency of CTGF promoter was in accordance with the higher expression of CTGF in trophoblast cells. Together, our data suggested an association between PE and the hypomethylation of CTGF promoter both in placentas and peripheral blood from a Chinese Han population.

17.
PLoS Comput Biol ; 16(2): e1007670, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32053592

RESUMO

Proteins in cellular environments are highly susceptible. Local perturbations to any residue can be sensed by other spatially distal residues in the protein molecule, showing long-range correlations in the native dynamics of proteins. The long-range correlations of proteins contribute to many biological processes such as allostery, catalysis, and transportation. Revealing the structural origin of such long-range correlations is of great significance in understanding the design principle of biologically functional proteins. In this work, based on a large set of globular proteins determined by X-ray crystallography, by conducting normal mode analysis with the elastic network models, we demonstrate that such long-range correlations are encoded in the native topology of the proteins. To understand how native topology defines the structure and the dynamics of the proteins, we conduct scaling analysis on the size dependence of the slowest vibration mode, average path length, and modularity. Our results quantitatively describe how native proteins balance between order and disorder, showing both dense packing and fractal topology. It is suggested that the balance between stability and flexibility acts as an evolutionary constraint for proteins at different sizes. Overall, our result not only gives a new perspective bridging the protein structure and its dynamics but also reveals a universal principle in the evolution of proteins at all different sizes.


Assuntos
Biologia Computacional/métodos , Conformação Proteica , Proteínas/química , Algoritmos , Sítio Alostérico , Catálise , Simulação por Computador , Cristalografia por Raios X , Bases de Dados de Proteínas , Elasticidade , Fractais , Proteínas de Choque Térmico HSP90/química , Humanos , Imageamento Tridimensional , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Distribuição Normal , Mapeamento de Interação de Proteínas , Relação Estrutura-Atividade
18.
Molecules ; 25(2)2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952238

RESUMO

'Ziyan' is a novel anthocyanin-rich tea cultivar with dark purple young shoots. However, how its anthocyanin accumulation is affected by environmental factors, such as ultraviolet (UV), remains unclear. In this study, we observed that UV light treatments stimulated anthocyanin accumulation in 'Ziyan' leaves, and we further analyzed the underlying mechanisms at gene expression and enzyme activity levels. In addition, the catechins and chlorophyll contents of young shoots under different light treatments were also changed. The results showed that the contents of total anthocyanins and three major anthocyanin molecules, i.e., delphinidin, cyanidin, and pelargonidin, were significantly higher in leaves under UV-A, UV-B, and UV-AB treatments than those under white light treatment alone. However, the total catechins and chlorophyll contents in these purple tea plant leaves displayed the opposite trends. The anthocyanin content was the highest under UV-A treatment, which was higher by about 66% than control. Compared with the white light treatment alone, the enzyme activities of chalcone synthase (CHS), flavonoid 3',5'-hydroxylase (F3'5'H), and anthocyanidin synthase (ANS) under UV treatments increased significantly, whereas the leucoanthocyanidin reductase (LAR) and anthocyanidin reductase (ANR) activities reduced. There was no significant difference in dihydroflavonol 4-reductase (DFR) activity under all treatments. Comparative transcriptome analyses unveiled that there were 565 differentially expressed genes (DEGs) of 29,648 genes in three pair-wise comparisons (white light versus UV-A, W vs. UV-A; white light versus UV-B, W vs. UV-A; white light versus UV-AB, W vs. UV-AB). The structural genes in anthocyanin pathway such as flavanone 3-hydroxylase (F3H), F3'5'H, DFR, and ANS, and regulatory gene TT8 were upregulated under UV-A treatment; F3'5'H, DFR, ANS, and UFGT and regulatory genes EGL1 and TT2 were upregulated under UV-AB treatment. However, most structural genes involved in phenylpropanoid and flavonoid pathways were downregulated under UV-B treatment compared with control. The expression of LAR and ANR were repressed in all UV treatments. Our results indicated that UV-A and UV-B radiations can induce anthocyanin accumulation in tea plant 'Ziyan' by upregulating the structural and regulatory genes involved in anthocyanin biosynthesis. In addition, UV radiation repressed the expression levels of LAR, ANR, and FLS, resulting in reduced ANR activity and a metabolic flux shift toward anthocyanin biosynthesis.

19.
World Neurosurg ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31931252

RESUMO

This article retrospectively studies patients undergoing radiofrequency ablation of atrial fibrillation, analyses the characteristics of heart rate variability in patients, and explores the role of DE-MRI imaging and autonomic nerve function, changes in autonomic nerve function, and recurrence after radiofrequency ablation of AF To understand the effect of denervation of autonomic nerves on the efficacy of radiofrequency ablation of AF. The study found that there were no significant differences in clinical baseline characteristics, MeanHR, and HRV indicators between patients without relapse and those with relapse (P> 0.05). The overall HRV index was significantly reduced after surgery and before surgery; in the relapse-free group, the HF that responded to vagal tone was more significant, LF / HF increased, and other HRV indicators were significantly reduced; in the relapse group, MeanHR increased, and sympathetic response The LF of nerve tension was significantly reduced, and the LF / HF was decreased. The difference was statistically significant (P <0.05). Therefore, sympathetic and parasympathetic nerve function were significantly reduced after radiofrequency ablation of the pulmonary veins in patients with AF. Reducing vague nerve tension may inhibit early recurrence of left atrial ring pulmonary vein ablation in patients with paroxysmal atrial fibrillation.

20.
Sci Total Environ ; 708: 134921, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31771854

RESUMO

The microorganisms contained in PM2.5 from livestock houses can spread over long distances through airborne transmission. As such, the potential bacterial pathogens and fungal allergens within can pose a formidable threat to nearby residents' health and the overall environment. However, little is known about the microbial assemblage contained in PM2.5 from pig houses. In this study, 16S and 18S rRNA gene sequencing was employed to analyze the bacterial and fungal assemblage contained in PM2.5 from a nursery pig house across four seasons, respectively. The results showed that alpha diversity was higher in summer and autumn compared to the spring and winter. The bacterial and fungal assemblage varied according to season. At the phylum level, the dominant bacteria and fungi were Firmicutes and Basidiomycota, respectively, across the four seasons. At the genus level, a total of five potential bacterial pathogen and 20 potential fungal allergen genera were identified across the samples. The most abundant bacterial pathogen and fungal allergen genera were observed in summer and autumn, respectively, but neither had a significant correlation with PM2.5 concentration. Moreover, microbial diversity and the relative abundance of fungal allergen genera were positively correlated with temperature and relative humidity. It can be concluded that microbial diversity and assemblage varied significantly among the seasons in a nursery pig house, and this can be useful in exploring the potential risks of PM2.5 from pig houses across all four seasons.

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