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1.
J Hazard Mater ; 383: 121190, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31541953

RESUMO

The conversion of silver materials in environments would impact their toxicity and risk. Previous studies have reported that silver ions (Ag+) could be reduced to silver nanoparticles (AgNPs) by natural organic matters (NOM) under sunlight or heating conditions. However, whether such reaction could occur in darkness at ambient temperature and the transformation mechanism were unclear. This study found that Ag+ at environmentally relevant concentrations (as low as 1 µg/L) could be reduced to AgNPs by Suwannee River humic acid (SRHA) in darkness at 30 °C. The reaction mechanism probed by X-ray absorption fine structure spectroscopy revealed that Ag+ was first bound to the carboxylic groups of SRHA to form Ag+-SRHA ligands, which were then reduced to metallic Ag. The increase of pH (6-9) and the coexistence of formate, acetate, carbonate, and sulfate promoted the formation of AgNPs. Besides, the formed AgNPs would coalesce to large aggregates under acidic conditions or in the presence of sulfate. These results suggest that the dark transformation of Ag+ to AgNPs mediated by NOM could occur in environments and are important for the better understanding of the natural origin of AgNPs.

2.
Mol Cell Endocrinol ; 499: 110603, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31574295

RESUMO

Activin/Smad3 signaling plays a pivotal role in follicle development and atresia. However, the precise mechanisms underlying this process are not yet fully understood. Herein, we identified miR-181a as a central component of activin/Smad3-mediated follicle atresia. miR-181a was strikingly upregulated in porcine atretic follicles, which induced the apoptosis of porcine granulosa cells (GCs) in vitro. Furthermore, the transforming growth factor-ß type 1 receptor (TGFBR1) was confirmed as a direct target of miR-181a by bioinformatics analysis and luciferase assays. Transfection with an miR-181a agomir repressed the TGFBR1 mRNA and protein levels. In addition, TGFBR1 overexpression repressed GC apoptosis, whereas TGFBR1 inhibition promoted GC apoptosis. miR-181a overexpression downregulated the phosphorylation of Smad3 and blocked the activation of TGF-ß signaling. Moreover, activin A downregulated miR-181a expression and upregulated the TGFBR1 and p-Smad3 protein levels. Collectively, these data suggest that miR-181a regulates porcine GC apoptosis by targeting TGFBR1 via the activin signaling pathway.

3.
Clin Plast Surg ; 47(1): 73-79, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31739900

RESUMO

This study used stromal vascular fraction gel (SVF-gel), a mechanically processed fat-derived product, to treat eye bag and tear trough deformity. SVF-gel is prepared by a process of centrifugation and intersyringe shifting and is particularly rich in SVF cells and native adipose extracellular matrix. SVF-gel injection is used alone or combined with transconjunctival eye bag removal. High satisfaction was noted among patients treated with SVF-gel injection for periorbital rejuvenation with fairly low complication rates. SVF-gel injection is a good alternative to assist transconjunctival lower eyelid blepharoplasty and correct the palpebromalar groove, tear trough deformity, and supraorbital hollow.

4.
Food Chem ; 306: 125629, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31629298

RESUMO

To understand the mechanism of the color formation of pepper fruit, integrative analysis of the metabolome and transcriptome profiles was performed in pepper varieties with 4 different fruit colors. A total of 188 flavonoids were identified, and most of the anthocyanins, flavonols and flavones showed markedly higher abundances in purple variety than in other varieties, which was linked to the high expression of flavonoid synthesis and regulatory genes. Using weighted gene co-expression network analyses, modules related to flavonoid synthesis and candidate genes that regulate flavonoid synthesis and transport were identified. Furthermore, the analysis of 12 carotenoids showed that the content of xanthophylls at 50 days after anthesis was significantly different between the four pepper varieties, which was resulted from the differential expressions of genes downstream of the carotenoid pathway. Our results provide new insights into the understanding of the synthesis and accumulation of flavonoids and carotenoids in pepper fruit.

5.
Talanta ; 207: 120293, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594564

RESUMO

Droplet digital PCR (ddPCR) has attracted much attention in the detection of genetic signatures of cancer present at low levels in circulating tumor DNA (ctDNA) in blood. A growing number of laboratory-developed liquid biopsy tests based on such technology have become commercially available for clinical settings. To obtain consistent and comparable results, an international standard is necessary for validation of the analytical performance. In this study, a novel and SI-traceable "ctDNA" reference material (RM) carrying BRAF V600E was prepared by gravimetrically mixing a 152 bp PCR amplicon and sonicated wild-type genomic DNA. The ddPCR performance was evaluated by analyzing serial "ctDNA" dilutions using a competitive MGB assay. The mutant frequency concordance (k) between ddPCR and the gravimetrical value was 1.03 in the range from 53.9% to 0.1%. The limit of blank (LoB), detection (LoD) and quantification (LoQ) of ddPCR assay were determined to be 0.01%, 0.02% and 0.1%, respectively. Results from the interlaboratory study, using challenging low levels of BRAF V600E ctDNA RMs, demonstrated that the participating laboratories had the appropriate technical competency to perform accurate ddPCR-based low level of ratio measurements. However, a systematic error caused by uncorrected droplet volume in Naica Crystal ddPCR platform was found by using the ctDNA RM. Between-laboratory consistency in copy number measurement was greatly improved when a correct droplet volume was applied for the ddPCR measurement by using the ctDNA RM. This confirms that the "ctDNA" RM is fit for the validation of ddPCR systems for ctDNA quantification. This would also support translation of tests for circulating tumor DNA by ddPCR into routine use.

6.
Plant Sci ; 290: 110295, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31779907

RESUMO

Among the phosphofructokinase B-type carbohydrate kinase (PCK) family proteins, only few proteins, like the FRUCTOKINASE-LIKE 1 and 2, have been functionally characterized in regulation of chloroplast development. Here, we report the involvement of a PCK protein PFKB1 in chloroplast development by identification of a new rice mutant, revertible early yellowing Kitaake 2 [rey(k2)]. The mutant rey(k2) shows yellow leaf phenotype, reduced photosynthetic pigments, and retarded chloroplast development during early stages of seedlings, but gradually recovered at later stages. The phenotype of rey(k2) is resulted from the disruption of the PFKB1 protein. The Pfkb1 gene is ubiquitously expressed, and its protein is mainly targeted to the chloroplast and, in some cells, to the nucleus. In addition, the PFKB1 protein possesses phosphofructokinase activity in vitro. The rey(k2) mutant affects RNA levels of chloroplast-associated genes. In particular, the nuclear-encoded RNA polymerase (NEP)-dependent genes are expressed at a sustained high level in rey(k2) even after turning green, indicating that PFKB1 is essential for suppressing the expression of NEP-dependent genes. Taken together, our study suggests that PFKB1 functions as a novel regulator indispensable for early chloroplast development, at least partly by regulating chloroplast-associated genes.

7.
Virology ; 539: 38-48, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31670218

RESUMO

Ionic calcium (Ca2+) is a versatile intracellular second messenger that plays important roles in cellular physiological and pathological processes. Porcine deltacoronavirus (PDCoV) is an emerging enteropathogenic coronavirus that causes serious vomiting and diarrhea in suckling piglets. In this study, the role of Ca2+ to PDCoV infection was investigated. PDCoV infection was found to upregulate intracellular Ca2+ concentrations of IPI-2I cells. Chelating extracellular Ca2+ by EGTA inhibited PDCoV replication, and this inhibitory effect was overcome by replenishment with CaCl2. Treatment with Ca2+ channel blockers, particularly the L-type Ca2+ channel blocker diltiazem hydrochloride, inhibited PDCoV infection significantly. Mechanistically, diltiazem hydrochloride reduces PDCoV infection by inhibiting the replication step of the viral replication cycle. Additionally, knockdown of CACNA1S, the L-type Ca2+ voltage-gated channel subunit, inhibited PDCoV replication. The combined results demonstrate that PDCoV modulates calcium influx to favor its replication.

8.
J Nanosci Nanotechnol ; 20(6): 3415-3423, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748034

RESUMO

G-C3N4 has a bright application prospect as an electrode material of supercapacitors, which makes it a concern. In order to increase the specific capacitance of g-C3N4, we consider to combine it with a metal oxide with high theoretical specific capacitance and utilize the synergistic effect. As a common metal oxide, CuO has the characteristics of high theoretical capacitance, high chemical stability, simple preparation and environmental friendliness. A composite containing CuO nanobelts and graphitic C3N4 (g-C3N4) was successfully synthesized by a chemical precipitation method. Various testing methods were used to explore its composition, microstructure and electrochemical properties to discuss whether CuO is suitable for improving the electrochemical properties of g-C3N4.

9.
Int J Hyg Environ Health ; 223(1): 171-178, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31548162

RESUMO

AIMS: Evidence concerning the impact of ambient particulate matter (PM) on mental health is just emerging and inconsistent. Air pollution with high PM levels has been frequently reported in China, however, no Chinese study has determined the association between PM exposures and anxiety hospitalizations. We examined the potential association between PM concentrations and anxiety admissions in 26 Chinese cities from January 2014 to December 2015. METHODS: A time-stratified case-crossover design was employed in the study. Anxiety hospitalizations were identified according to ICD-10 from the electronic hospitalization summary reports system in China. Conditional logistic regression was applied to estimate the relation between PM levels and anxiety admissions, stratified by age and sex. RESULTS: Positive associations between PM2.5/PM10 and admitted anxiety cases were observed. PM2.5 had the largest effect estimate at lag 5 days, with a per 10 µg/m3 increase corresponding to a 0.63% (95% CI, 0.26-1.00) increase in anxiety admissions. PM10's largest effect estimate was observed at lag 3 days, increasing 0.37% (95% CI, 0.12-0.62) anxiety admissions per 10 µg/m3. Females were more sensitive to PM2.5/PM10 concentrations than males, however, the effect modification by age was not significant. A marginally significant distinction in anxiety hospitalizations was found in patients with and without CVDs when they were exposed to PM2.5. CONCLUSIONS: Our findings indicate that short-term exposure to increased concentrations of PM2.5/PM10 exacerbates risks of anxiety hospitalizations in 26 Chinese cities. We observed effect modification by sex, with significantly stronger associations in female patients. This study offers the promise that reducing PM air pollution could probably reduce the huge disease burden from anxiety disorders.

10.
Anal Chim Acta ; 1094: 151-159, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31761042

RESUMO

Based on superparamagnetic nanoparticles, a responsive polyacrylamide hydrogel self-assembled by nucleic acid hairpin hybridization chain reaction was designed, and a universal low field nuclear magnetic resonance sensing platform was successfully constructed. As the target was gradually added, the hydrogel coating on the surface of the magnetic nanoparticle was opened layer by layer through binding with the aptamer, which specifically bonded thereto, causing different degrees of exposure of the magnetic nanoparticle, resulting in changes of low field nuclear magnetic resonance signals. This method was originally applied to the rapid detection of adenosine triphosphate (ATP), and the versatility of the method was verified using polychlorinated biphenyl 77 (PCB77). This method had the advantage of being fast, convenient, and low cost, and it can be easily operated with high repeatability. This universal method can detect a variety of targets by replacing aptamers and may be useful in controlling food quality and for rapidly detecting cancer cells in vitro.

11.
Diabetologia ; 63(1): 21-33, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31482198

RESUMO

AIMS/HYPOTHESIS: A healthy lifestyle has been widely recommended for the prevention and management of type 2 diabetes. However, no systematic review has summarised the relationship between combined lifestyle factors (including, but not limited to, smoking, alcohol drinking, physical activity, diet and being overweight or obese) and incident type 2 diabetes and risk of health outcomes among diabetic individuals. METHODS: EMBASE and PubMed were searched up to April 2019 without language restrictions. References included in articles in relevant publications were also screened. Cohort studies investigating the combined associations of at least three lifestyle factors with incident type 2 diabetes and health outcomes among diabetic individuals were included. Reviewers were paired and independently screened studies, extracted data and evaluated study quality. Random-effects models were used to calculate summary HRs. Heterogeneity and publication bias tests were also conducted. RESULTS: Compared with participants considered to have the least-healthy lifestyle, those with the healthiest lifestyle had a 75% lower risk of incident diabetes (HR 0.25 [95% CI 0.18, 0.35]; 14 studies with approximately 1 million participants). The associations were largely consistent and significant among individuals from different socioeconomic backgrounds and baseline characteristics. Among individuals with type 2 diabetes (10 studies with 34,385 participants), the HRs (95% CIs) were 0.44 (0.33, 0.60) for all-cause death, 0.51 (0.30, 0.86) for cardiovascular death, 0.69 (0.47, 1.00) for cancer death and 0.48 (0.37, 0.63) for incident cardiovascular disease when comparing the healthiest lifestyle with the least-healthy lifestyle. CONCLUSIONS/INTERPRETATION: Adoption of a healthy lifestyle is associated with substantial risk reduction in type 2 diabetes and long-term adverse outcomes among diabetic individuals. Tackling multiple risk factors, instead of concentrating on one certain lifestyle factor, should be the cornerstone for reducing the global burden of type 2 diabetes.

12.
Neurosci Lett ; 714: 134603, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31693931

RESUMO

The tree shrew is susceptible to stimuli. However, mapping of c-Fos expression in male tree shrew forebrain has not been explored. The present results provided the first detailed mapping of c-Fos expression in the forebrain of the tree shrew (Tupaia belangeri chinensis). Acute restraint stress rapidly increased the density of c-Fos-immunoreactive (-ir) neurons in the medial orbital cortex (MO), infralimbic cortex, intermediate part of the lateral septal nucleus (LSi), ventral part of the lateral septal nucleus (LSv), anterior part of the bed nucleus of the stria terminalis, posterior part of the bed nucleus of the stria terminalis (STP), paraventricular nucleus of the hypothalamus, supraoptic nucleus, lateral hypothalamic area, ventromedial hypothalamic nucleus (VMH), and medial amygdaloid nucleus (MeA). Furthermore, a significant increase in c-Fos expression was observed in the MO, LSi, LSv, STP, VMH, arcuate hypothalamic nucleus, anterior amygdaloid area, MeA, and cortical amygdaloid nucleus immediately after acute footshock stress. In addition, the distinct patterns of c-Fos expression in the forebrain were shown in context-, restraint-, or footshock-treated tree shrews. In general, the present study provides the first detailed maps of c-Fos expression in male tree shrew forebrain immediately after various stimuli.

13.
J Cell Biochem ; 121(1): 418-429, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31222836

RESUMO

Excessive mechanical tension can lead to the degeneration of endplate chondrocytes. The presence of tension-sensitive circRNA_0058097 molecules has been detected in human endplate chondrocytes, where it was found to be a potential competing endogenous RNA. Indeed, inhibiting the expression of circRNA_0058097 effectively enhanced the stress resistance of endplate chondrocytes, suggesting that it may be an important trigger point for the degeneration of endplate cartilage. Through a series of experiments, we reveal that circRNA_0058097 can upregulate the expression of downstream target gene histone deacetylase 4 by sponge adsorption of miR-365a-5p, which promoted morphological changes of endplate chondrocytes, and increased extracellular matrix degradation and degeneration of endplate cartilage. Therefore, circRNA_0058097 may provide a new way to prevent and treat endplate cartilage degeneration.

14.
J Transcult Nurs ; 31(1): 76-86, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30957667

RESUMO

Introduction: The risk for cardiovascular disease (CVD) is higher in South Asians (SAs) than in other ethnic groups. The purpose of this review is to explore SAs' health beliefs regarding CVD risk and risk reduction behaviors including physical activity and healthy diet. Methodology: An integrative review was conducted to examine the peer-reviewed literature published before May 2017. Searches from PubMed, Scopus, and CINAHL yielded 1 mixed-method, 4 quantitative, and 14 qualitative studies. Results: Stress, lack of exercise, and high-fat diet were perceived as causes of CVD in most studies. Lack of time, sociocultural norms, and insufficient guidance from health care providers were perceived barriers to CVD risk reduction. Exercise and healthy diet were perceived to be beneficial in a few studies. Cues to action included information from community leaders and health care providers. Discussion: Understanding the unique health beliefs of SAs regarding CVD is important in planning and delivering culturally competent preventive and educational services.

15.
Health Soc Care Community ; 28(1): 225-235, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31508864

RESUMO

This study investigates the characteristics of Chinese older people receiving home and community care and the factors associated with the sources of payment for care services. The data come from the Social Survey of Older People in Urban China, which collected information from a random sample of 3,247 older people aged 60 and over in 10 large cities in different regions of China in 2017. Anderson's behavioural model of care utilisation is used to guide the analyses. The study identifies four striking features of the Chinese social care system. First, although disabilities are a significant predictor of receiving home and community care, a large proportion of care recipients do not have disabilities. Second, perceived proximity of care is the most important predictor, which implies high elasticity of demand for care services with regard to perceived distance and the great geographical inequality of care resources in the cities. Third, the government policies support the use of the internet to facilitate care access, but the enabling effect of the internet among older people is limited. Finally, sources of payment for care differ significantly according to people's age, living arrangements, disability and level of education. We argue that the government should consider shifting the focus of financial support from service providers to care recipients in the future.

16.
17.
Biosci Biotechnol Biochem ; 84(1): 85-94, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31794329

RESUMO

Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) regulates collagen-mediated platelet activation through its cytoplasmic immunoreceptor tyrosine-based inhibition motifs (ITIMs). However, the function of CEACAM1's extracellular cleavage fragments is currently unknown. In the present study, we used mass spectrometry (MS) to identify 9 cleavage fragments shed by matrix metallopeptidase 12 (MMP-12), and then we synthesized peptides with sequences corresponding to the fragments. QLSNGNRTLT (QLSN), a peptide from the A1-domain of CEACAM1, significantly attenuated collagen-induced platelet aggregation. QLSN also attenuated platelet static adhesion to collagen. Additionally, QLSN reduced human platelet secretion and integrin αIIbß3 activation in response to glycoprotein VI (GPVI)-selective agonist, convulxin. Correspondingly, QLSN treatment significantly decreased convulxin-mediated phosphorylation of Src, protein kinase B (Akt), spleen tyrosine kinase (Syk) and phospholipase Cγ2 (PLCγ2) in human platelets. These data indicate that the CEACAM1-derived peptide QLSN inhibits GPVI-mediated human platelet activation. QLSN could potentially be developed as a novel antiplatelet agent.

18.
Chemosphere ; 238: 124603, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31442773

RESUMO

Environmental pollution is a risk factor for kidney dysfunction. However, the combined toxicity of air pollutants on kidney function is scarce. We estimated the relationship between combined toxicity of air pollutants and kidney function among adult women (n = 7071, 18-65 years old) in Mianyang City, Southwest China. We measured serum concentrations of uric acid, urea, creatinine, and cystatin C, and we calculated the individual estimated glomerular filtration rate (eGFR) using a cystatin C-based equation developed specifically for Chinese patients with CKD equation. Air pollution data were collected to calculate the individual average daily dose (ADD) of pollutants based on the air quality complex index (AQCI). Mean AQCI was higher in winter and lower in summer, and followed the monthly and seasonal trends of air pollutants. Concomitantly, individual ADD was also higher in winter and lower in summer, and the seasonal differences were reflected in the levels of kidney biomarkers (including uric acid, urea, creatinine, cystatin C, and eGFR). With an interquartile range (IQR: 1.04-1.50 m3/day/kg) increases of ADD, the serum concentrations of uric acid, urea, creatinine, and cystatin C increase [B (95%CI): 1.774 (0.318, 3.231) umol/L, 0.218 (0.1888, 0.247) mmol/L, 1.501 (1.016, 1.986) umol/L, and 0.006 (0.003, 0.009) mg/L, respectively], whereas eGFR decreases [B (95%CI): -0.776 (-1.106, -0.446) mL/min/1.73 m2]. Totally, the relationship between combined toxicity of air pollutants and kidney function in Chinese adult women suggests that the toxicity of combined air pollutants inversely affects kidney function, which might accelerate the risk of CKD.

19.
Biochim Biophys Acta Mol Cell Res ; : 118617, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31785334

RESUMO

Sequestration of misfolded proteins into distinct cellular compartments plays a pivotal role in proteostasis and proteopathies. Cytoplasmic ubiquitinated proteins are sequestered by p62/SQSTM1 to deposit in sequestosomes or aggresome-like induced structures (ALIS). Most aggresome or ALIS regulators identified thus far are recruiters, while little is known about the disaggregases or dissolvers. In this research, we showed that lanosterol synthase and its enzymatic product lanosterol effectively reduced the number and/or size of sequestosomes/ALIS/aggresomes formed by endogenous proteins in the HeLa and HEK-293A cells cultured under both non-stressed and stressed conditions. Supplemented lanosterol did not affect the proteasome and autophagic activities, but released the trapped proteins from the p62-positive inclusions accompanied with the activation of HSF1 and up-regulation of various heat shock proteins. Our results suggested that the coordinated actions of disaggregation by lanosterol and refolding by heat shock proteins might facilitate the cells to recycle proteins from aggregates. The disaggregation activity of lanosterol was not shared by cholesterol, indicating that lanosterol possesses additional cellular functions in proteostasis regulation. Our findings highlight that besides protein modulators, the cells also possess endogenous low-molecular-weight compounds as efficient proteostasis regulators.

20.
J Proteomics ; : 103598, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31785380

RESUMO

Porcine circovirus type 3 (PCV3) infection induces porcine dermatitis and nephropathy syndrome, reproductive failure, and multisystemic inflammatory lesions in piglets and sows. To better understand the host responses to PCV3 infection, isobaric tags for relative and absolute quantification (iTRAQ) labeling combined with LC-MS/MS analysis was used for quantitative determination of differentially regulated cellular proteins in the lungs of specific-pathogen-free piglets after 4 weeks of PCV3 infection. Totally, 3429 proteins were detected in three independent mass spectrometry analyses, of which 242 differential cellular proteins were significantly regulated, consisting of 100 upregulated proteins and 142 downregulated proteins in PCV3-infected group relative to control group. Bioinformatics analysis revealed that these higher or lower abundant proteins involved primarily metabolic processes, innate immune response, MHC-I and MHC-II components, and phagosome pathways. Ten genes encoding differentially regulated proteins were selected for investigation via real-time RT-PCR. The expression levels of six representative proteins, OAS1, Mx1, ISG15, IFIT3, SOD2, and HSP60, were further confirmed by Western blotting and immunohistochemistry. This study attempted for the first time to investigate the protein profile of PCV3-infected piglets using iTRAQ technology; our findings provide valuable information to better understand the mechanisms underlying the host responses to PCV3 infection in piglets. SIGNIFICANCE: Our study identified differentially abundant proteins related to a variety of potential signaling pathways in the lungs of PCV3-infected piglets. These findings provide valuable information to better understand the mechanisms of host responses to PCV3 infection.

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