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1.
Zhongguo Zhong Yao Za Zhi ; 46(3): 591-598, 2021 Feb.
Artículo en Chino | MEDLINE | ID: mdl-33645024

RESUMEN

Nano-LC MS/MS was used to analyze trypsin digested deer-hide gelatin(DHG) samples, hydroxylation and O-glycosylation on lysine sites of DHG were comprehensive identified by using PEAKS Studio software. The sites, sorts and amounts of hydroxylation and O-glycosylation on Type Ⅰ collagen α1 chain(COL1 A1) and α2 chain(COL1 A2) of DHG were revealed. As a result, 5 284 peptides were identified from DHG samples, which were mainly from COL1 A1 and COL1 A2. Among these peptides, there were 449 peptides with hydroxylysine, 442 with galactosyl-hydroxylysine, 449 with glucosyl-galactosyl-hydroxylysine. The major modified sites of hydroxylation and O-glycosylation in DHG were shown as follow: α1-9 N and α2-5 N in N-telopeptides, α1-87, α1-174, α1-930, α2-87, α2-174, α2-933 in triple helix domain, and α1-16 C in C-telopeptides. These hydroxylation and O-glycosylation were correlated with the formation and stability of collagen molecules and collagen fibrils. It is feasible for the collagens and peptides dissolving from deer skin collagen fibrils under high temperature and pressure decocting, high temperature and pressure also might destroy inter-molecular covalent cross-linking and help those glycol-peptides formations. The present study provided ideas and strategies for the in-depth investigation on DHG chemical constituents, and showed good theoretical significance and application value.

2.
J Biomed Mater Res A ; 2021 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-33650768

RESUMEN

A promising strategy that emerged in tissue engineering is to incorporate two-dimensional (2D) materials into polymer scaffolds, producing materials with desirable mechanical properties and surface chemistries, which also display broad biocompatibility. Black phosphorus (BP) is a 2D material that has sparked recent scientific interest due to its unique structure and electrochemical characteristics. In this study, BP nanosheets (BPNSs) were incorporated into a cross-linkable oligo[poly(ethylene glycol) fumarate] (OPF) hydrogel to produce a new nanocomposite for bone regeneration. BPNSs exhibited a controllable degradation rate coupled with the release of phosphate in vitro. MTS assay results together with live/dead images confirmed that the introduction of BPNSs into OPF hydrogels enhanced MC3T3-E1 cell proliferation. Moreover, the morphology parameters indicated better attachments of cells in the BPNSs containing group. Immunofluorescence images as well as intercellular ALP and OCN activities showed that adding a certain amount of BPNSs to OPF hydrogel could greatly improve differentiation of pre-osteoblasts on the hydrogel. Additionally, embedding black phosphorous into a neutral polymer network helped to control its cytotoxicity, with optimal cell growth observed at BP concentrations as high as 500 ppm. These results reinforced that the supplementation of OPF with BPNSs can increase the osteogenic capacity of polymer scaffolds for use in bone tissue engineering.

3.
Sleep Breath ; 2021 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-33619665

RESUMEN

BACKGROUND: Sleep deprivation (SD) has become a serious concern worldwide. This study aimed to identify key modules and candidate hub genes correlated with diseases caused by SD, using co-expression analysis. METHODS: The weighted gene co-expression network analysis was performed to construct a co-expression network of hub genes correlated with SD. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed to search for signaling pathways. The protein-protein interaction network analysis of central genes was performed to recognize the interactions among central genes. Molecular Complex Detection, a plugin in Cytoscape, was used to discover the hub gene clusters involved in SD. RESULTS: A total of 564 genes in the yellow module were identified based on the results of topological overlap measure-based clustering. The yellow module showed a pivotal correlation with SD. Six hub gene clusters prominently associated with SD were identified. Heat shock protein family and circadian clock genes among them may be the hub genes involved in SD. CONCLUSIONS: These genes and pathways might become therapeutic targets with clinical usefulness in the future.

4.
Oral Dis ; 2021 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-33529425

RESUMEN

OBJECTIVE: Primary cilia, evolutionally conserved organelles involving multiple cell functions, are frequently lost in various cancers. However, little is known about the role of primary cilia in oral squamous cell carcinoma (OSCC). METHODS: Immunofluorescence staining was applied to detect primary cilia in normal, oral leukoplakia (OLK) and OSCC tissues. Differentially expressed ciliary genes of OSCC were screened from the TCGA database. Immunohistochemical analysis was used for validating the correlation between the expression of interested proteins and primary cilia, and their regulatory effect on primary cilia was further proved in vitro and in vivo. RESULTS: A significant decrease in cilia ratio was found in OLK, especially in OSCC. Multiple ciliary genes were abnormally expressed in OSCC and epidermal growth factor receptor (EGFR)-Aurora A signaling was chosen for further study. A parallel increase of EGFR-Aurora A was observed in OLK and OSCC tissues. Moreover, EGFR activation induced obvious cilia absorption by phosphorylating Aurora A. Besides, Aurora A silencing significantly restored ciliary expression and decreased tumor growth in vivo. CONCLUSIONS: The abnormal activation of EGFR-Aurora A leads to the gradual loss of primary cilia in oral mucosa carcinogenesis. Primary cilia have the potential to be new biomarkers and therapeutic targets of oral cancer.

5.
Int J Med Sci ; 18(6): 1415-1422, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33628098

RESUMEN

Objective: SARS-CoV-2 (originally named COVID-2019) pneumonia is currently prevalent worldwide. The number of cases has increased rapidly but the auscultatory characteristics of affected patients and how to use it to predict who is most likely to survive or die are not available. This study aims to describe the auscultatory characteristics and its clinical relativity of SARS-CoV-2 pneumonia by using a wireless stethoscope. Material and methods: A cross-sectional, observational, single-center case series of 30 consecutive hospitalized patients with confirmed SARS-CoV-2 pneumonia at Leishenshan Hospital in Wuhan, China, were enrolled from March 9 to April 5, 2020. Clinical, laboratory, radiological, treatment data and lung auscultation were collected and analyzed. Lung auscultation was acquired by a wireless electronic stethoscope. Auscultatory characteristics of the moderate, severe, and critically ill patients were compared. Results: Kinds of crackles including fine crackles and wheezing were heard and recorded in these patients. Velcro crackles were heard in most critically ill patients (6/10). Besides, patients with Velcro crackles were all dead (6/6). There was no positive lung auscultatory finding in the moderate group and little positive lung auscultatory findings (4/10) in the severe group. Conclusion: Velcro crackles can be auscultated by this newly designed electronic wireless stethoscope in most critically ill patients infected by SARS-CoV-2 and predicts a poor prognosis. Moderate and severe patients without positive auscultatory findings may have a better prognosis.

6.
Arthritis Res Ther ; 23(1): 58, 2021 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-33602317

RESUMEN

BACKGROUND: Our previous studies reveal that impaired draining function of the synovial lymphatic vessel (LV) contributes to the pathogenesis of inflammatory arthritis, but the cellular and molecular mechanisms involved are not fully understood. OBJECTIVE: To investigate the involvement of lymphatic muscle cells (LMCs) in mediating impaired LV function in inflammatory arthritis. METHODS: TNF transgenic (TNF-Tg) arthritic mice were used. The structure and function of the LVs that drained the hind limbs were examined by whole-mount immunofluorescence staining, electron microscopy, and near-infrared lymphatic imaging. Primary LMCs were treated with TNF, and the changes in proliferation, apoptosis, and functional gene expression were assessed. The roles of the herbal drug, Panax notoginseng saponins (PNS), in arthritis and LVs were studied. RESULTS: TNF-Tg mice developed ankle arthritis with age, which was associated with abnormalities of LVs: (1) dilated capillary LVs with few branch points, (2) mature LVs with reduced LMC coverage and draining function, and (3) degenerative and apoptotic appearance of LMCs. TNF caused LMC apoptosis, reduced expression of muscle functional genes, and promoted the production of nitric oxide (NO) by lymphatic endothelial cells (LECs). PNS attenuated arthritis, restored LMC coverage and draining function of mature LVs, inhibited TNF-mediated NO expression, and reduced LMC apoptosis. CONCLUSION: The impaired draining function of LVs in TNF-Tg mice involves LMC apoptosis. TNF promotes LMC death directly and indirectly via NO production by LECs. PNS attenuates arthritis, improves LVs, and prevents TNF-induced LMC apoptosis by inhibiting NO production of LECs. LMCs contribute to the dysfunction of synovial LVs in inflammatory arthritis.

7.
Nat Commun ; 12(1): 983, 2021 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-33579949

RESUMEN

The state of ecosystems is influenced strongly by their past, and describing this carryover effect is important to accurately forecast their future behaviors. However, the strength and persistence of this carryover effect on ecosystem dynamics in comparison to that of simultaneous environmental drivers are still poorly understood. Here, we show that vegetation growth carryover (VGC), defined as the effect of present states of vegetation on subsequent growth, exerts strong positive impacts on seasonal vegetation growth over the Northern Hemisphere. In particular, this VGC of early growing-season vegetation growth is even stronger than past and co-occurring climate on determining peak-to-late season vegetation growth, and is the primary contributor to the recently observed annual greening trend. The effect of seasonal VGC persists into the subsequent year but not further. Current process-based ecosystem models greatly underestimate the VGC effect, and may therefore underestimate the CO2 sequestration potential of northern vegetation under future warming.

8.
Sensors (Basel) ; 21(4)2021 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-33562385

RESUMEN

A breathing crack is a typical form of structural damage attributed to long-term dynamic loads acting on engineering structures. Traditional linear damage identification methods suffer from the loss of valuable information when structural responses are essentially non-linear. To deal with this issue, bispectrum analysis is employed to study the non-linear dynamic characteristics of a beam structure containing a breathing crack, from the perspective of numerical simulation and experimental validation. A finite element model of a cantilever beam is built with contact elements to simulate a breathing crack. The effects of crack depth and location, excitation frequency and magnitude, and measurement noise on the non-linear behavior of the beam are studied systematically. The result demonstrates that bispectral analysis can effectively identify non-linear damage in different states with strong noise immunity. Compared with existing methods, the bispectral non-linear analysis can efficiently extract non-linear features of a breathing crack, and it can overcome the limitations of existing linear damage detection methods used for non-linear damage detection. This study's outcome provides a theoretical basis and a paradigm for damage identification in cracked structures.

9.
Andrologia ; : e14005, 2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33565168

RESUMEN

This study evaluates the protective role of oyster peptide (OP) on the occurrence of Exercise-Hypogonadal Male Condition. Male rats were given heavy-load swimming training and / or OP was supplemented for 6 consecutive weeks. After heavy-load training, sperm count, sperm viability and sperm motility in epididymis, testosterone in serum and testis, glutathione peroxidase (GSH-px) and androgen receptor (AR) in testis and mating times were remarkably decreased, malondialdehyde (MDA), capture latency and mating latency were significantly increased, mRNA expression of steroidogenic acute regulatory (StAR) and P450 cholesterol side-chain cleavage enzyme (P450scc) were obviously down-regulated, but serum follicle-stimulating hormone (FSH) and luteinising hormone (LH) were not statistically changed. Conversely, when OP was supplemented at heavy-load training, sperm count, sperm viability and sperm motility in epididymis, serum FSH, LH, testosterone, GSH-px, superoxide dismutase (SOD), testosterone, AR in testis and mating times were dramatically increased, while testicular MDA, capture latency and mating latency were significantly decreased, and mRNA expression of StAR, StARD7, P450scc and 3ß-hydroxysteroid dehydrogenase (3ß-HSD) were significantly up-regulated. In conclusion, heavy-load training causes testicular spermatogenic and steroidogenic disorders by enhancing the generation of reactive oxygen species (ROS), which can be protected by the co-administration of OP by enhancing the function of pituitary gonad axis and lowering ROS generation.

10.
EJNMMI Phys ; 8(1): 12, 2021 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-33555478

RESUMEN

BACKGROUND: Standardized uptake value (SUV) normalized by lean body mass ([LBM] SUL) is recommended as metric by PERCIST 1.0. The James predictive equation (PE) is a frequently used formula for LBM estimation, but may cause substantial error for an individual. The purpose of this study was to introduce a novel and reliable method for estimating LBM by limited-coverage (LC) CT images from PET/CT examinations and test its validity, then to analyse whether SUV normalised by LC-based LBM could change the PERCIST 1.0 response classifications, based on LBM estimated by the James PE. METHODS: First, 199 patients who received whole-body PET/CT examinations were retrospectively retrieved. A patient-specific LBM equation was developed based on the relationship between LC fat volumes (FVLC) and whole-body fat mass (FMWB). This equation was cross-validated with an independent sample of 97 patients who also received whole-body PET/CT examinations. Its results were compared with the measurement of LBM from whole-body CT (reference standard) and the results of the James PE. Then, 241 patients with solid tumours who underwent PET/CT examinations before and after treatment were retrospectively retrieved. The treatment responses were evaluated according to the PE-based and LC-based PERCIST 1.0. Concordance between them was assessed using Cohen's κ coefficient and Wilcoxon's signed-ranks test. The impact of differing LBM algorithms on PERCIST 1.0 classification was evaluated. RESULTS: The FVLC were significantly correlated with the FMWB (r=0.977). Furthermore, the results of LBM measurement evaluated with LC images were much closer to the reference standard than those obtained by the James PE. The PE-based and LC-based PERCIST 1.0 classifications were discordant in 27 patients (11.2%; κ = 0.823, P=0.837). These discordant patients' percentage changes of peak SUL (SULpeak) were all in the interval above or below 10% from the threshold (±30%), accounting for 43.5% (27/62) of total patients in this region. The degree of variability is related to changes in LBM before and after treatment. CONCLUSIONS: LBM algorithm-dependent variability in PERCIST 1.0 classification is a notable issue. SUV normalised by LC-based LBM could change PERCIST 1.0 response classifications based on LBM estimated by the James PE, especially for patients with a percentage variation of SULpeak close to the threshold.

11.
Cell Chem Biol ; 2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33567254

RESUMEN

Phenotypic screening for bioactive small molecules is typically combined with affinity-based chemical proteomics to uncover the respective molecular targets. However, such assays and the explored bioactivity are biased toward the monitored phenotype, and target identification often requires chemical derivatization of the hit compound. In contrast, unbiased cellular profiling approaches record hundreds of parameters upon compound perturbation to map bioactivity in a broader biological context and may link a profile to the molecular target or mode of action. Herein we report the discovery of the diaminopyrimidine DP68 as a Sigma 1 (σ1) receptor antagonist by combining morphological profiling using the Cell Painting assay and thermal proteome profiling. Our results highlight that integration of complementary profiling approaches may enable both detection of bioactivity and target identification for small molecules.

12.
Nature ; 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33536623

RESUMEN

Tissue-resident innate lymphoid cells (ILCs) help sustain barrier function and respond to local signals. ILCs are traditionally classified as ILC1, ILC2 or ILC3 on the basis of their expression of specific transcription factors and cytokines1. In the skin, disease-specific production of ILC3-associated cytokines interleukin (IL)-17 and IL-22 in response to IL-23 signalling contributes to dermal inflammation in psoriasis. However, it is not known whether this response is initiated by pre-committed ILCs or by cell-state transitions. Here we show that the induction of psoriasis in mice by IL-23 or imiquimod reconfigures a spectrum of skin ILCs, which converge on a pathogenic ILC3-like state. Tissue-resident ILCs were necessary and sufficient, in the absence of circulatory ILCs, to drive pathology. Single-cell RNA-sequencing (scRNA-seq) profiles of skin ILCs along a time course of psoriatic inflammation formed a dense transcriptional continuum-even at steady state-reflecting fluid ILC states, including a naive or quiescent-like state and an ILC2 effector state. Upon disease induction, the continuum shifted rapidly to span a mixed, ILC3-like subset also expressing cytokines characteristic of ILC2s, which we inferred as arising through multiple trajectories. We confirmed the transition potential of quiescent-like and ILC2 states using in vitro experiments, single-cell assay for transposase-accessible chromatin using sequencing (scATAC-seq) and in vivo fate mapping. Our results highlight the range and flexibility of skin ILC responses, suggesting that immune activities primed in healthy tissues dynamically adapt to provocations and, left unchecked, drive pathological remodelling.

13.
Oral Dis ; 2021 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-33529456

RESUMEN

OBJECTIVE: To examine the comparative efficacy and safety of topical administration for oral lichen planus. MATERIALS AND METHODS: An electronic database search (1st January 1946 to 1st May 2020) for randomised controlled trials identified 34 studies involving eight interventions (clobetasol, betamethasone, triamcinolone, dexamethasone, fluocinolone, tacrolimus, pimecrolimus, and cyclosporine); these studies were subjected to network meta-analysis using direct and indirect comparisons [efficacy indicators: clinical response rate, symptom-reducing effect (visual analogue scale score), sign-reducing effect (Thongprasom-scale score) and relapse; safety indicator: adverse event occurrence]. RESULTS: Compared with placebo, tacrolimus had the best clinical response rate (odds ratio (OR), 57.78 [95% CI 3.15-1060.52]; P-score, 0.8654) and cyclosporine had the worst (OR, 3.61[95% CI 0.20-66.62]; P-score, 0.2236); tacrolimus had the best symptom-reducing effect (standardised mean difference (SMD), 1.06 [95% CI 0.41-1.71]; P-score, 0.9323) and fluocinolone had the worst (SMD, -0.54 [95% CI -1.44-0.36]; P-score, 0.0157); dexamethasone had the best sign-reducing effect (SMD, 3.60 [95% CI 1.74-5.45]; P-score, 0.8306) and clobetasol had the worst (SMD, 2.63 [95% CI 1.66-3.61]; P-score, 0.2581); and pimecrolimus performed best (OR, 0.04 [95% CI 0.00-0.64]; P-score, 0.9227) and clobetasol performed the worst [OR, 0.60; 95% CI 0.15-2.45; P-score, 0.2545] in reducing relapse. Regarding safety, dexamethasone was the safest compared with placebo [OR, 0.37; 95% CI 0.05-2.57; P-score, 0.9337), whereas fluocinolone ranked low for safety [OR, 9.48; 95% CI 1.50- 60.03; P-score, 0.1189]. CONCLUSIONS: The relative ranking of topical administration varies according to the different indicators. Based on the joint consideration of clinical response rate and adverse event occurrence, dexamethasone, triamcinolone and betamethasone are recommended for better efficacy and safety. The optimal treatment for oral lichen patients varies under different conditions.

14.
JAMA Netw Open ; 4(2): e2037554, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33595663

RESUMEN

Importance: Extremely low diastolic blood pressure has been reported to be associated with increased adverse cardiovascular events (ie, the diastolic J-shape phenomenon); however, current US guidelines recommend an intensive blood pressure target of less than 130/80 mm Hg without mentioning the lower limits of diastolic blood pressure. Objectives: To evaluate whether there is a diastolic J-shape phenomenon for patients with an treated systolic blood pressure of less than 130 mm Hg and to explore the safe and optimal diastolic blood pressure ranges for this patient population. Design, Setting, and Participants: This cohort study analyzed outcome data of patients at high cardiovascular risk who were randomized to intensive or standard blood pressure control and achieved treated systolic blood pressure of less than 130 mm Hg in the Systolic Blood Pressure Intervention Trial (SPRINT) and Action to Control Cardiovascular Risk in Diabetes-Blood Pressure (ACCORD-BP) trial. Data were collected from October 2010 to August 2015 (SPRINT) and from September 1999 to June 2009 (ACCORD-BP). Data were analyzed from January to May 2020. Exposure: Treated diastolic blood pressure, divided in intervals of less than 60, 60 to less than 70, 70 to less than 80, and 80 mm Hg and greater. Main Outcomes and Measures: The primary outcome was a composite of all-cause death, nonfatal myocardial infarction, and nonfatal stroke. A composite cardiovascular outcome, including cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke, was among the key secondary outcomes. Results: A total of 7515 patients (mean [SD] age, 65.6 [8.7] years; 4553 [60.6%] men) were included in this analysis. The nominally lowest risk was observed at a diastolic blood pressure between 70 and 80 mm Hg for the primary outcome, the composite cardiovascular outcome, nonfatal myocardial infarction, and cardiovascular death. A mean diastolic blood pressure of less than 60 mm Hg was associated with significantly increased risk of the primary outcome (hazard ratio [HR], 1.46; 95% CI, 1.13-1.90; P = .004), the composite cardiovascular outcome (HR, 1.74; 95% CI, 1.26-2.41; P = .001), nonfatal myocardial infarction (HR, 1.73; 95% CI, 1.15-2.59; P = .008), and nonfatal stroke (HR, 2.67; 95% CI, 1.26-5.63; P = .01). Conclusions and Relevance: This cohort study found that lowering diastolic blood pressure to less than 60 mm Hg was associated with increased risk of cardiovascular events in patients with high cardiovascular risk and an treated systolic blood pressure less than 130 mm Hg. The finding that a diastolic blood pressure value between 70 and 80 mm Hg was an optimum target for this patient population merits further study.

15.
Bioresour Technol ; 326: 124768, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33529982

RESUMEN

Corncob is an abundant and renewable resource that could be enzymatically hydrolyzed to fermentable sugar. A major impediment in corncob utilization is the low hydrolysis efficiency at high-solids content. This study attempted different pretreatment methods and fed-batch modes to achieve a 25% solids content hydrolysis with high yields. Natural corncobs were compared with acid-treated and acid-alkali-treated corncobs in terms of kinetics parameters, conversion rate and glucose titer. By feeding in batches, a "low amount and high frequency" mode (10%-3%-3%-3%-3%-3%, every 5 h) was confirmed to be optimal for a 25% high-solids hydrolysis system with a cellulase loading of 12 mg/g (7.3 FPU/g), resulted with an 84.4% glucose yield at 96 h. Our results demonstrated that combination of both optimized pretreatment method and fed-batch mode were a favored process model for high-solids hydrolysis of lignocellulose, boosting cellulose hydrolysis efficiency and sugar yields on an industrial scale.


Asunto(s)
Celulasa , Zea mays , Álcalis , Celulosa , Hidrólisis
16.
Artículo en Inglés | MEDLINE | ID: mdl-33449427

RESUMEN

Herein we report visible-light-induced intramolecular double dearomative cycloaddition of arenes. Compared with the well-known photodimerization of arenes under ultraviolet irradiation, the current reactions are carried out under mild conditions and feature wide substrate scope. A large array of structurally-diverse polycyclic indoline derivatives is afforded in high yields (up to 98 %) with exclusive diastereoselectivity (>20:1 dr) via dearomative [4+2] or [2+2] pathway.

17.
Environ Pollut ; 273: 116467, 2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33453699

RESUMEN

As zoned areas of industries, industrial parks have great impacts on the environment. Several studies have demonstrated that chemical compounds and heavy metals released from industrial parks can contaminate soil, water, and air. However, as an emerging pollutant, antimicrobial resistance genes (ARGs) in industrial parks have not yet been investigated. Here, we collected soil samples from 35 sites in an industrial park in China and applied a metagenomics strategy to profile the ARGs and virulence factors (VFs). We further compared the relative abundance of ARGs between the sites (TZ_31-35) located in a beta-lactam antimicrobial-producing factory and other sites (TZ_1-30) in this industrial park. Metagenomic sequencing and assembly generated 14, 383, 065 contigs and 17, 631, 051 open reading frames (ORFs). Taxonomy annotation revealed Proteobacteria and Actinobacteria as the most abundant phylum and class, respectively. The 32 pathogenic bacterial genera listed in the virulence factor database (VFDB) were all identified from the soil metagenomes in this industrial park. In total, 685,354 ARGs (3.89% of the ORFs) and 272,694 virulence factors (VFs) (1.55% of the ORFs) were annotated. These ARGs exhibited resistance to several critically important antimicrobials, such as rifampins, fluroquinolones, and beta-lactams. In addition, no significant difference in the relative abundance of ARGs was observed between sites TZ_31-35 and TZ_1-30, indicating that ARGs have already disseminated widely in this industrial park. The present study gave us a better understanding of the whole picture of the resistome and virulome in the soil of the industrial park and suggested that we should treat the industrial park as a whole in the surveillance and maintenance of ARGs.

18.
Biology (Basel) ; 10(2)2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33513687

RESUMEN

Hepatic steatosis caused by starvation, resulting in non-alcoholic fatty liver disease (NAFLD), has been a research topic of human clinical and animal experiments. To understand the molecular mechanisms underlying the triggering of abnormal liver metabolism by starvation, thus inducing hepatic lipid accumulation, we used zebrafish larvae to establish a starvation-induced hepatic steatosis model and conducted comparative transcriptome analysis by RNA-seq. We demonstrated that the incidence of larvae steatosis is positively correlated with starvation time. Under starvation conditions, the fatty acid transporter (slc27a2a and slc27a6-like) and fatty acid translocase (cd36) were up-regulated significantly to promote extrahepatic fatty acid uptake. Meanwhile, starvation inhibits the hepatic fatty acid metabolism pathway but activates the de novo lipogenesis pathway to a certain extent. More importantly, we detected that the expression of numerous apolipoprotein genes was downregulated and the secretion of very low density lipoprotein (VLDL) was inhibited significantly. These data suggest that starvation induces hepatic steatosis by promoting extrahepatic fatty acid uptake and lipogenesis, and inhibits hepatic fatty acid metabolism and lipid transport. Furthermore, we found that starvation-induced hepatic steatosis in zebrafish larvae can be rescued by targeting the knockout cd36 gene. In summary, these findings will help us understand the pathogenesis of starvation-induced NAFLD and provide important theoretical evidence that cd36 could serve as a potential target for the treatment of NAFLD.

19.
J Chem Phys ; 154(4): 044701, 2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33514096

RESUMEN

Although large-radius carbon nanotubes (CNTs) are now available in macroscopic quantities, little is known about their condensed phase. Large-scale density functional theory calculations predict a low energy phase in which the same-diameter "dog-bone" collapsed CNTs form a graphite-like phase with complex, anomalous grain boundaries (GBs). The excess GB volume does not prevent the strong van der Waals coupling of the flattened CNT sides into AB stacking. The associated GB energetics is dominated by the van der Waals energy penalty and high curvature bending of the loop CNT edges, which exhibit reactivity and flexoelectricity. The large density and superior mechanical rigidity of the proposed microstructural organization as well as the GB flexoelectricity are desirable properties for developing ultra-strong composites based on large-radius CNTs.

20.
Rev Sci Instrum ; 92(1): 015105, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33514197

RESUMEN

Ultrasonic gas flow meters are especially suitable for measurement in pipelines with large diameters. However, on the one hand, it is difficult to find a stable feature point to calculate the duration of propagation of the ultrasonic signal, through which we can obtain the real-time flow rate of the gas, and on the other hand, the computation incurred by signal processing methods to this end is burdensome and affects the real-time performance of the flow meter. To solve these problems, this study examines the characteristics of the stability of the echo signal and patterns of variation in the echo contour at different flow rates of gas. We found that peak points of the middle part of the rising segment of the echo signal were relatively stable, and the slope of the envelope of this part was always relatively large but constant, which indicates that peak points in this part were approximately distributed along a straight line. This finding is used to develop a signal processing method based on the connection fitting of the echo peak point with a large slope. This method is easy to implement, incurs a small amount of calculation, and has strong anti-interference ability. Moreover, it can guide research on signal processing methods and the stability of the echo signal. The proposed method was implemented on a dual-core hardware system, and the results of calibration show that it can attain 1.0-level accuracy over a measurable range of 30 m3/h-1100 m3/h.

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