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1.
Chin Med J (Engl) ; 133(10): 1144-1154, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32433046

RESUMO

BACKGROUND: The association of milk intake with cardiovascular disease (CVD) and cause-specific mortality remained controversial and evidence among the Chinese population was limited. We aimed to study the relationship between milk intake and CVDs among general Chinese adults. METHODS: A total of 104,957 participants received questionnaire survey. Results of physical examination such as anthropometric measurements and biochemical tests during 2007 to 2008, demographic data and their information on milk intake were collected through standardized questionnaires. Cox proportional hazard regression models were used to calculate hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) of CVD incidence, cause-specific mortality and all-cause mortality related to milk intake. Restricted cubic splines (RCSs) were applied to examine dose-response associations. RESULTS: Among the 91,757 participants with a median follow-up period of 5.8 years, we documented 3877 CVD cases and 4091 all-cause deaths. Compared with participants who never consumed milk, the multivariate-adjusted HRs (95% CIs) of CVD incidence for 1 to 150 g/day, 151 to 299 g/day, and ≥300 g/day were 0.94 (0.86-1.03) (P > 0.05), 0.77 (0.66-0.89) (P < 0.05), and 0.59 (0.40-0.89) (P < 0.05), respectively; each 100 g increase of daily milk intake was associated with 11% lower risk of CVD incidence (HR, 0.89; 95% CI: 0.85-0.94; P < 0.001), and 11% lower risk of CVD mortality (HR, 0.89; 95% CI: 0.82-0.97; P = 0.008) after adjustment for age, sex, residential area, geographic region, education level, family history of CVD, smoking, alcohol drinking, physical activity level, body mass index, and healthy diet status (ideal or not). RCS analyses also showed a linear dose-response relationship with CVD (P for overall significance of the curve <0.001; P for non-linearity = 0.979; P for linearity <0.001) and stroke (P for overall significance of the curve = 0.010; P for non-linearity = 0.998; P for linearity = 0.002) incidence, and CVD mortality (P for overall significance of the curve = 0.045; P for non-linearity = 0.768; P for linearity = 0.014) within the current range of daily milk intake. CONCLUSIONS: Daily milk intake was associated with lower risk of CVD incidence and mortality in a linear inverse relationship. The findings provide new evidence for dietary recommendations in CVD prevention among Chinese adults and people with similar dietary pattern in other countries.

2.
Nano Lett ; 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32431154

RESUMO

Liposomal drug delivery for cancer therapy can be limited due to drug leakage in circulation. Here, we develop a new method to enhance the stability of actively loaded liposomal doxorubicin (DOX) through embedding a stiff nanobowl in the liposomal water cavity. Nanobowl-supported liposomal DOX (DOX@NbLipo) resists the influence of plasma protein and blood flow shear force to prevent drug leakage. This approach yields improved drug delivery to tumor sites and enhanced antitumor efficacy. Compared to alternative methods of modifying liposome surface and composition for stability, this approach designs a physical support for an all-aqueous nanoliposomal cavity. Nanobowl stabilization of liposomes is a simple and effective method to improve carrier stability and drug delivery.

3.
Biomed Res Int ; 2020: 4569037, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32309431

RESUMO

As an important category of proteins, alpha-helix transmembrane proteins (αTMPs) play an important role in various biological activities. Because the solved αTMP structures are inadequate, predicting the residue contacts among the transmembrane segments of an αTMP exhibits the basis of protein fold, which can be used to further discover more protein functions. A few efforts have been devoted to predict the interhelical residue contact using machine learning methods based on the prior knowledge of transmembrane protein structure. However, it is still a challenge to improve the prediction accuracy, while the deep learning method provides an opportunity to utilize the structural knowledge in a different insight. For this purpose, we proposed a novel αTMP residue-residue contact prediction method IMPContact, in which a convolutional neural network (CNN) was applied to recognize those interhelical contacts in a TMP using its specific structural features. There were four sequence-based TMP-specific features selected to descript a pair of residues, namely, evolutionary covariation, predicted topology structure, residue relative position, and evolutionary conservation. An up-to-date dataset was used to train and test the IMPContact; our method achieved better performance compared to peer methods. In the case studies, IHRCs in the regular transmembrane helixes were better predicted than in the irregular ones.

4.
Mar Pollut Bull ; 154: 111089, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32319918

RESUMO

Investigating the heterogeneous distribution pattern of plastic pollution in river systems is useful for better understanding the transport pathways of plastics from land to sea. Therefore, we analyzed samples from 17 sites to evaluate the distribution pattern of microplastics (MPs) in Minjiang River Watershed. The MP concentrations ranged between 0.12 and 2.72 n/L, with higher microplastic concentrations located in urban areas with greater population and gross domestic product (GDP) densities. MP concentrations were positively correlated with population density, GDP density, and built-up land use percentage, suggesting that increasing urbanization level will lead to greater plastic pollution. MP concentrations spanning the upstream and downstream sides of the SK Hydropower Dam showed decreasing trends, suggesting that MP settling would occur behind the dam and Shuikou Reservoir might serve as a sink for MPs. This study provides useful insight for revealing the effects of urbanization and dams on spatial distribution of riverine MPs.

5.
ACS Appl Mater Interfaces ; 12(18): 20321-20330, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32293862

RESUMO

Metal-organic frameworks (MOFs) have been identified as promising materials for the delivery of therapeutics to cure cancer owing to their intrinsic porous structure. However, in a majority of cases, MOFs act as only a delivery cargo for anticancer drugs while little attention has been focused on the utilization of their intriguing physical and chemical properties for potential anticancer purposes. Herein for the first time, an ultrathin (16.4 nm thick) ferrocene-based MOF (Zr-Fc MOF) nanosheet has been synthesized for synergistic photothermal therapy (PTT) and Fenton reaction-based chemodynamic (CDT) therapy to cure cancer without additional drugs. The Zr-Fc MOF nanosheet acts not only as an excellent photothermal agent with a prominent photothermal conversion efficiency of 53% at 808 nm but also as an efficient Fenton catalyst to promote the conversion of H2O2 into hydroxyl radical (•OH). As a consequence, an excellent therapeutic performance has been achieved in vitro as well as in vivo through this combinational effect. This work aims to construct an "all-in-one" MOF nanoplatform for PTT and CDT treatments without incorporating any additional therapeutics, which may launch a new era in the investigation of MOF-based synergistic therapy platforms for cancer therapy.

6.
J Mater Chem B ; 8(17): 3929-3938, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32232281

RESUMO

Developing drug delivery platforms that can modulate a tumor microenvironment and deliver multiple therapeutics to targeted tumors is critical for efficient cancer treatment. Achieving these platforms still remains a great challenge. Herein, biodegradable nanocapsules based on MnFe hydroxides (H-MnFe(OH)x) have been developed as a new type of cargo delivery with high loading capacity and catalytic activity, enabling synergetic therapy with promoted efficacy by relieving hypoxia in tumor tissues. As a proof of concept, a photosensitizer (indocyanine green, ICG) and a chemotherapeutic drug (doxorubicin, DOX) are co-loaded in nanocapsules and selectively released upon degradation of the nanocapsules in the acidic tumor microenvironment, and are promoted by near infrared irradiation. Meanwhile, Mn2+/Fe3+ ions released from the degradation of nanocapsules catalyze the conversion of H2O2 in a tumor microenvironment into oxygen, which modulates tumor hypoxia and dramatically boosts multimodal therapies. Remarkable synergistic anticancer outcomes have been demonstrated both in vitro and in vivo, paving the way towards future multifunctional therapeutic platforms.

7.
Nat Genet ; 52(4): 428-436, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32231277

RESUMO

Adaptive changes in plant phenology are often considered to be a feature of the so-called 'domestication syndrome' that distinguishes modern crops from their wild progenitors, but little detailed evidence supports this idea. In soybean, a major legume crop, flowering time variation is well characterized within domesticated germplasm and is critical for modern production, but its importance during domestication is unclear. Here, we identify sequential contributions of two homeologous pseudo-response-regulator genes, Tof12 and Tof11, to ancient flowering time adaptation, and demonstrate that they act via LHY homologs to promote expression of the legume-specific E1 gene and delay flowering under long photoperiods. We show that Tof12-dependent acceleration of maturity accompanied a reduction in dormancy and seed dispersal during soybean domestication, possibly predisposing the incipient crop to latitudinal expansion. Better understanding of this early phase of crop evolution will help to identify functional variation lost during domestication and exploit its potential for future crop improvement.

8.
Chin Med J (Engl) ; 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32304403

RESUMO

BACKGROUND: The association of milk intake with cardiovascular disease (CVD) and cause-specific mortality remained controversial and evidence among the Chinese population was limited. We aimed to study the relationship between milk intake and CVDs among general Chinese adults. METHODS: A total of 104,957 participants received questionnaire survey. Results of physical examination such as anthropometric measurements and biochemical tests during 2007 to 2008, demographic data and their information on milk intake were collected through standardized questionnaires. Cox proportional hazard regression models were used to calculate hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) of CVD incidence, cause-specific mortality and all-cause mortality related to milk intake. Restricted cubic splines (RCSs) were applied to examine dose-response associations. RESULTS: Among the 91,757 participants with a median follow-up period of 5.8 years, we documented 3877 CVD cases and 4091 all-cause deaths. Compared with participants who never consumed milk, the multivariate-adjusted HRs (95% CIs) of CVD incidence for 1 to 150 g/day, 151 to 299 g/day, and ≥300 g/day were 0.94 (0.86-1.03) (P > 0.05), 0.77 (0.66-0.89) (P < 0.05), and 0.59 (0.40-0.89) (P < 0.05), respectively; each 100 g increase of daily milk intake was associated with 11% lower risk of CVD incidence (HR, 0.89; 95% CI: 0.85-0.94; P < 0.001), and 11% lower risk of CVD mortality (HR, 0.89; 95% CI: 0.82-0.97; P = 0.008) after adjustment for age, sex, residential area, geographic region, education level, family history of CVD, smoking, alcohol drinking, physical activity level, body mass index, and healthy diet status (ideal or not). RCS analyses also showed a linear dose-response relationship with CVD (P for overall significance of the curve <0.001; P for non-linearity = 0.979; P for linearity <0.001) and stroke (P for overall significance of the curve = 0.010; P for non-linearity = 0.998; P for linearity = 0.002) incidence, and CVD mortality (P for overall significance of the curve = 0.045; P for non-linearity = 0.768; P for linearity = 0.014) within the current range of daily milk intake. CONCLUSIONS: Daily milk intake was associated with lower risk of CVD incidence and mortality in a linear inverse relationship. The findings provide new evidence for dietary recommendations in CVD prevention among Chinese adults and people with similar dietary pattern in other countries.

9.
J Microbiol Methods ; 172: 105894, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32184161

RESUMO

BACKGROUND AND AIM: The rapid diagnosis of bloodstream infection (BSI) often leads to better clinical outcomes. The present study was conducted to compare two rapid protocols (Sepsityper kit and short-term subculture) for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)-based identification of microorganisms from positive blood cultures in pediatric patients. METHODS: This study was conducted between May 1, 2018, and April 30, 2019, at a tertiary children's hospital in eastern China. Only monomicrobial blood cultures included in this study were used to conduct the Sepsityper kit protocol and short-term subculture protocol at the same time. RESULTS: In total, 115 monomicrobial blood cultures were included in this study. For the Sepsityper kit protocol, 85.2% and 64.3% of microorganisms were correctly identified to the genus (score ≥ 1.700) and species levels (score ≥ 2.000), respectively. For the short-term subculture protocol, 89.6% and 70.4% of microorganisms were correctly identified to the genus and species levels, respectively. At the genus level (P = .321) or the species level (P = .325), there was no significant difference between the Sepsityper kit protocol and the short-term subculture protocol. Moreover, the short-term subculture protocol exhibited similar performance between Gram-positive bacteria (GPB) and Gram-negative bacteria (GNB) (the genus level: 93.7% (GPB) versus 87.9% (GNB), P = .518; the species level: 68.4% (GPB) versus 81.8% (GNB), P = .147). In addition, the Sepsityper kit protocol exhibited similar performance between GPB and GNB at the genus level (86.1% (GPB) versus 84.8% (GNB), P = 1.000). However, the Sepsityper kit protocol exhibited better performance in GNB at the species level (58.2% (GPB) versus 81.8% (GNB), P = .017). The rates of yeast-like fungi were correctly identified to the genus level (0.0%) or the species level (0.0%) for short-term subculture protocol were significantly lower than those of other microorganisms (the genus level: 92.0%, P = .001; the species level: 72.3%, P = .024). However, a similar result of identification was not found using the Sepsityper kit protocol (the genus level: P = .384; the species level: P = .599). In addition, the two rapid protocols both exhibited better performance at the genus level when the time to positivity (TTP) of blood cultures <19 h (the Sepsityper kit protocol: 91.8% (TTP < 19 h) versus 77.8% (TTP ≥ 19 h), P = .034; the short-term subculture protocol: 95.1% (TTP < 19 h) versus 83.3% (TTP ≥ 19 h), P = .040). In addition, the two rapid protocols both exhibited better performance at the species level when the TTP of blood cultures was <19 h (the Sepsityper kit protocol: 78.7% (TTP < 19 h) versus 48.1% (TTP ≥ 19 h), P = .000; the short-term subculture protocol: 83.6% (TTP < 19 h) versus 55.6% (TTP ≥ 19 h), P = .001). CONCLUSION: The Sepsityper kit protocol and short-term subculture protocol are both reliable and rapid methods for the identification of most microorganisms from positive blood cultures in pediatric patients. The performance of these two rapid protocols is associated with the TTP of blood cultures.

10.
Biophys J ; 118(8): 1811-1819, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32197062

RESUMO

A current bottleneck in the advance of neurophysics is the lack of reliable methods to quantitatively measure the interactions between neural cells and their microenvironment. Here, we present an experimental technique to probe the fundamental characteristics of neuron adhesion through repeated peeling of well-developed neurite branches on a substrate with an atomic force microscopy cantilever. At the same time, a total internal reflection fluorescence microscope is also used to monitor the activities of neural cell adhesion molecules (NCAMs) during detaching. It was found that NCAMs aggregate into clusters at the neurite-substrate interface, resulting in strong local attachment with an adhesion energy of ∼0.1 mJ/m2 and sudden force jumps in the recorded force-displacement curve. Furthermore, by introducing a healing period between two forced peelings, we showed that stable neurite-substrate attachment can be re-established in 2-5 min. These findings are rationalized by a stochastic model, accounting for the breakage and rebinding of NCAM-based molecular bonds along the interface, and provide new insights into the mechanics of neuron adhesion as well as many related biological processes including axon outgrowth and nerve regeneration.

11.
J Cell Mol Med ; 24(9): 5122-5134, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32185887

RESUMO

Angelica sinensis (AS; Dang Gui), a traditional Chinese herb, has for centuries been used for the treatment of bone diseases, including osteoporosis and osteonecrosis. However, the effective ingredient and underlying mechanisms remain elusive. Here, we identified guaiacol as the active component of AS by two-dimensional cell membrane chromatography/C18 column/time-of-flight mass spectrometry (2D CMC/C18 column/TOFMS). Guaiacol suppressed osteoclastogenesis and osteoclast function in bone marrow monocytes (BMMCs) and RAW264.7 cells in vitro in a dose-dependent manner. Co-immunoprecipitation indicated that guaiacol blocked RANK-TRAF6 association and RANK-C-Src association. Moreover, guaiacol prevented phosphorylation of p65, p50, IκB (NF-κB pathway), ERK, JNK, c-fos, p38 (MAPK pathway) and Akt (AKT pathway), and reduced the expression levels of Cathepsin K, CTR, MMP-9 and TRAP. Guaiacol also suppressed the expression of nuclear factor of activated T-cells cytoplasmic 1(NFATc1) and the RANKL-induced Ca2+ oscillation. In vivo, it ameliorated ovariectomy-induced bone loss by suppressing excessive osteoclastogenesis. Taken together, our findings suggest that guaiacol inhibits RANKL-induced osteoclastogenesis by blocking the interactions of RANK with TRAF6 and C-Src, and by suppressing the NF-κB, MAPK and AKT signalling pathways. Therefore, this compound shows therapeutic potential for osteoclastogenesis-related bone diseases, including postmenopausal osteoporosis.

12.
Nutrients ; 12(3)2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32120990

RESUMO

Adequate calorie restriction (CR) as a healthy lifestyle is recommended not only for people with metabolic disorders but also for healthy adults. Previous studies have mainly focused on the beneficial metabolic effects of CR on obese subjects, while its effects on non-obese subjects are still scarce. Here, we conducted a three-week non-controlled CR intervention in 41 subjects, with approximately 40% fewer calories than the recommended daily energy intake. We measured BMI, and applied targeted metabolic profiling on fasting blood samples and shotgun metagenomic sequencing on fecal samples, before and after intervention. Subjects were stratified into two enterotypes according to their baseline microbial composition, including 28 enterotype Bacteroides (ETB) subjects and 13 enterotype Prevotella (ETP) subjects. CR decreased BMI in most subjects, and ETP subjects exhibited a significantly higher BMI loss ratio than the ETB subjects. Additionally, CR induced limited changes in gut microbial composition but substantial microbial-independent changes in blood AAs, including a significant increase in 3-methylhistidine, a biomarker of the skeletal muscle protein turnover. Finally, baseline abundances of seven microbial species, rather than baseline AA levels, could well predict CR-induced BMI loss. This non-controlled intervention study revealed associations between baseline gut microbiota and CR-induced BMI loss and provided evidence to accelerate the application of microbiome stratification in future personalized nutrition intervention.

13.
Arch Gynecol Obstet ; 301(4): 963-971, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32193602

RESUMO

PURPOSE: Circular RNAs (circRNAs) are widely expressed noncoding RNAs which play important roles in various processes. The present study aimed to explore the effect of maternal PCOS on the expression of circRNAs in fetus and assessed the potential role of circRNA in human ovarian granulosa cell proliferation. METHODS: Total RNA was extracted from the fetal side of placental tissues from maternal PCOS (n = 3) and healthy puerpera (n = 3) for circRNA microarray. Real-time reverse transcriptase quantitative PCR (RT-qPCR) was used to validate the microarray data in fetal side of placental tissues from puerpera with (n = 18) and without (n = 30) PCOS. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were applied to predict the functions and pathways of circ_0023942 host genes. The circRNA-miRNA-mRNA network was constructed through bioinformatics prediction. Circ_0023942 overexpression vector was transiently transfected into human ovarian granulosa cell lines KGN and COV434. Cell proliferation was detected by cell counting kit-8. The protein expression level was determined by western blot. RESULTS: Compared with healthy puerpera, 14 circRNAs were significantly upregulated and 101 circRNAs were significantly downregulated in the fetal side of placenta from maternal PCOS according to the microarray data. Six differentially expressed circRNAs were selected for validation by RT-qPCR, and the expression patterns of circ_0023942, circ_0002151, circ_0001274, and circ_0008514 were consistent with the microarray data. Circ_0023942 was chosen for further investigation. GO and KEGG analysis predicted that circ_0023942 participated in the regulation of developmental process and the MAPK signaling pathway. Seven miRNAs were predicted to be the targets of circ_0023942. Overexpression of circ_0023942 inhibited human ovarian granulosa cell proliferation and suppressed the expression of CDK-4. CONCLUSION: Maternal PCOS impairs circ_0023942 expression in fetus. Overexpression of circ_0023942 inhibits human ovarian granulosa cell proliferation possibly via regulating CDK-4.

14.
Circulation ; 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32200651

RESUMO

Background: Branched-chain amino acids (BCAAs), essential nutrients including leucine, isoleucine and valine, serve as a resource for energy production and the regulator of important nutrient and metabolic signals. Recent studies have suggested that dysfunction of BCAA catabolism is associated with a risk of cardiovascular disease. Platelets play an important role in cardiovascular disease, but the functions of BCAA catabolism in platelets remain unknown. Methods: The activity of human platelets from healthy subjects before and after ingestion of BCAAs were measured. Protein phosphatase 2Cm (PP2Cm) specifically dephosphorylates branched-chain α-keto acid dehydrogenase, and thereby activates BCAA catabolism. PP2Cm deficient mice were used to elucidate the impacts of BCAA catabolism on platelet activation and thrombus formation. Results: We found that ingestion of BCAAs significantly promoted human platelet activity (n=5, P<0.001) and arterial thrombosis formation in mice (n=9, P<0.05). We also found that the valine catabolite α-ketoisovaleric acid (KIV) and the ultimate oxidation product propionyl-coenzyme A showed the strongest promotion effects on platelet activation, suggesting that the valine/KIV catabolic pathway plays a major role in BCAA-facilitated platelet activation. PP2Cm deficiency significantly suppresses the activity of platelets in response to agonists (n=5, P<0.05). Our results also suggested that BCAA metabolic pathways may be involved in the integrin αIIbß3-mediated bidirectional signaling pathway that regulates platelet activation. Mass spectrometry identification and immunoblotting revealed that BCAAs enhanced propionylation of tropomodulin-3 at K255 in platelets or CHO cells expressing integrin αIIbß3. The tropomodulin-3 K255A mutation abolished propionylation and attenuated the promotion effects of BCAAs on integrin-mediated cell spreading, suggesting that K255 propionylation of tropomodulin-3 is an important mechanism underlying integrin αIIbß3-mediated BCAA-facilitated platelet activation and thrombosis formation. Additionally, the increased levels of BCAAs and the expression of positive regulators of BCAA catabolism in platelets from type 2 diabetes mellitus patients are significantly correlated with platelet hyperreactivity. Lowering dietary BCAA intake significantly reduced platelet activity in ob/ob mice (n=4, P<0.05). Conclusions: BCAA catabolism is an important regulator of platelet activation and is associated with arterial thrombosis risk. Targeting the BCAA catabolism pathway or lowering dietary BCAA intake may serve as a novel therapeutic strategy for metabolic syndrome-associated thrombophilia.

15.
Genome Biol ; 21(1): 24, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-32014062

RESUMO

BACKGROUND: Regulation of transcription depends on interactions between cis-regulatory elements (CREs) and regulatory proteins. Active CREs are imbedded in open chromatin that are accessible to nucleases. Several techniques, including DNase-seq, which is based on nuclease DNase I, and ATAC-seq, which is based on transposase Tn5, have been widely used to identify genomic regions associated with open chromatin. These techniques have played a key role in dissecting the regulatory networks in gene expression in both animal and plant species. RESULTS: We develop a technique, named MNase hypersensitivity sequencing (MH-seq), to identify genomic regions associated with open chromatin in Arabidopsis thaliana. Genomic regions enriched with MH-seq reads are referred as MNase hypersensitive sites (MHSs). MHSs overlap with the majority (~ 90%) of the open chromatin identified previously by DNase-seq and ATAC-seq. Surprisingly, 22% MHSs are not covered by DNase-seq or ATAC-seq reads, which are referred to "specific MHSs" (sMHSs). sMHSs tend to be located away from promoters, and a substantial portion of sMHSs are derived from transposable elements. Most interestingly, genomic regions containing sMHSs are enriched with epigenetic marks, including H3K27me3 and DNA methylation. In addition, sMHSs show a number of distinct characteristics including association with transcriptional repressors. Thus, sMHSs span distinct classes of open chromatin that may not be accessible to DNase I or Tn5. We hypothesize that the small size of the MNase enzyme relative to DNase I or Tn5 allows its access to relatively more condensed chromatin domains. CONCLUSION: MNase can be used to identify open chromatin regions that are not accessible to DNase I or Tn5. Thus, MH-seq provides an important tool to identify and catalog all classes of open chromatin in plants.

16.
Ecotoxicol Environ Saf ; 192: 110271, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32044605

RESUMO

Pollution with total petroleum hydrocarbons (TPHs) is a global concern and particularly in coastal environments. Polycyclic aromatic hydrocarbons (PAHs) are regarded as the most toxic components of TPHs and they can also be derived from other sources. Fangcheng Port is considered as a representative emerging coastal city in China, but the status, sources, and hazards to organisms and humans with respect to contamination with PAHs and TPHs are unknown in the coastal regions of this area. Therefore, in this study, we cloned cytochrome P450 family genes (CYP1A1, CYP3A, and CYP4) and heat shock protein 70 gene (HSP70) in the clam Meretrix meretrix as well as optimizing the method for measuring the 7-ethoxyresorufin O-deethylase activity. These molecular indicators and four specific physiological indexes were found to be appropriate biomarkers for indicating the harmful effects of PAHs and TPHs on clams after exposure to the crude oil water-soluble fraction. In field monitoring surveys, we found that the 2- and 3-ring PAHs were dominant in the clams whereas the 4- to 6-ring PAHs were dominant in the sediments at each site. The PAH levels (3.63-12.77 ng/g wet weight) in wild clams were lower, whereas the TPH levels (13.25-70.50 µg/g wet weight) were higher compared with those determined previous in China and elsewhere. The concentrations of PAHs and TPHs in the sediments (19.20-4215.76 ng/g and 3.65-866.40 µg/g dry weight) were moderate compared with those in other global regions. Diagnostic ratio analysis demonstrated that the PAHs were derived mainly from pyrogenic sources. The TPHs may have come primarily from industrial effluents, land and maritime transportation, or fishing activities. The Integrated Biomarker Response version 2 indexes indicated that the clams collected from site S5 exhibited the most harmful effects due to contamination by PAHs and TPHs. Human health risk assessments demonstrated that the risks due to PAHs and TPHs following the consumption of clams can be considered acceptable. Our results suggest that continuous monitoring of contamination by PAHs and TPHs is recommended in this emerging coastal city as well as assessing their human health risks.


Assuntos
Monitoramento Biológico/métodos , Bivalves/efeitos dos fármacos , Biomarcadores Ambientais/efeitos dos fármacos , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Animais , Bivalves/metabolismo , China , Cidades , Humanos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Urbanização , Poluentes Químicos da Água/metabolismo
18.
Curr Microbiol ; 77(6): 953-958, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31989212

RESUMO

The present study aimed to investigate the relationship between the time to positivity (TTP) of blood cultures and the performance of short-term subculture for MALDI-TOF MS-based identification of microorganisms from positive blood cultures in pediatric patients. The study was conducted between April 2018 and July 2019 at a tertiary children's hospital in Eastern China and the TTP of all the blood cultures included was retrospectively collected at the same time. In total, 332 monomicrobial blood cultures were included in the study. Blood cultures that were identified at the genus level (score ≥ 1.700) by the short-term subculture protocol had shorter TTP (median TTP: 17.5 h) than of those not identified (median TTP: 24.6 h; P < 10-3). Those that were identified at the species level (score ≥ 2.000) by the short-term subculture protocol also had shorter TTP (median TTP: 16.7 h) than of those not identified (median TTP: 21.7 h; P < 10-3). ROC curve analysis indicated that the TTP cutoff value to the genus level of the short-term subculture protocol was 18.2 h (area under the curve (AUC): 0.801; 95% confidence interval (CI) 0.741-0.861; P < 10-3). At the same time, the TTP cutoff value to the species level of the short-term subculture protocol was 18.1 h (AUC: 0.747; 95% CI 0.694-0.800; P < 10-3). TTP is a convenient and valuable prognostic tool for the determination of the performance of short-term subculture for MALDI-TOF MS-based identification of microorganisms from positive blood cultures in pediatric patients.

19.
Environ Sci Technol ; 54(7): 4564-4572, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-31977202

RESUMO

Complete dechlorination and mineralization of chlorophenols via the reduction-oxidation-mediated electro-Fenton process with a composite bulk cathode is first proposed. The in situ formation of a PdFe nanoalloy and carbon defects as key active sites is mutually induced during the formation of a carbon aerogel-based electrode. Specifically, the PdFe nanoalloy promotes the generation of [H]ads as reduction sites and improves the electron transfer via an electrical circuit, while the carbon defects selectively favor the 2e- oxygen reduction pathway. Notably, this work implies a novel electrocatalytic model for the formation of ·OH via (2 + 1)e- oxygen reduction by a consecutive reaction with carbon defects and a PdFe nanoalloy. Complete total organic carbon removal and dechlorination of 3-chlorophenol were performed after 6 h. The kinetic rate constant for removing haloacetamides (HAMs) in drinking water was 0.21-0.41 h-1, and the degradation efficiency was self-enhanced after electrolysis for 2 h because of the increased concentration of [H+]. The specific energy consumption was ∼0.55 W·h·g-1 at 100% removal of some HAMs, corresponding to a power consumption of 0.6-1.1 kW·h for complete dehalogenation per ton of drinking water in waterworks. Moreover, the PdFe alloy/CA exhibited extreme mechanical and electrochemical stability with limited iron (∼0.07 ppm) and palladium (0.02 ppm) leaching during the actual application.

20.
PLoS One ; 15(1): e0227587, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923275

RESUMO

Diffusing fluid at a deep-sea hydrothermal vent creates rapid, acute physico-chemical gradients that correlate strongly with the distribution of the vent fauna. Two alvinocaridid shrimps, Alvinocaris longirostris and Shinkaicaris leurokolos occupy distinct microhabitats around these vents and exhibit different thermal preferences. S. leurokolos inhabits the central area closer to the active chimney, while A. longirostris inhabits the peripheral area. In this study, we screened candidate genes that might be involved in niche separation and microhabitat adaptation through comparative transcriptomics. The results showed that among the top 20% of overexpressed genes, gene families related to protein synthesis and structural components were much more abundant in S. leurokolos compared to A. longirostris. Moreover, 15 out of 25 genes involved in cellular carbohydrate metabolism were related to trehalose biosynthesis, versus 1 out of 5 in A. longirostris. Trehalose, a non-reducing disaccharide, is a multifunctional molecule and has been proven to act as a protectant responsible for thermotolerance in Saccharomyces cerevisiae. Putative positively selected genes involved in chitin metabolism and the immune system (lectin, serine protease and antimicrobial peptide) were enriched in S. leurokolos. In particular, one collagen and two serine proteases were found to have experienced strong positive selection. In addition, sulfotransferase-related genes were both overexpressed and positively selected in S. leurokolos. Finally, genes related to structural proteins, immune proteins and protectants were overexpressed or positively selected. These characteristics could represent adaptations of S. leurokolos to its microhabitat, which need to be confirmed by more evidence, such as data from large samples and different development stages of these alvinocaridid shrimps.


Assuntos
Aclimatação/genética , Adaptação Fisiológica/genética , Decápodes/genética , Animais , Crustáceos/genética , Ecossistema , Perfilação da Expressão Gênica/métodos , Fontes Hidrotermais , Filogenia , Transcriptoma/genética
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