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1.
Environ Microbiol ; 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33000483

RESUMO

Ascospores are the primary inoculum in Fusarium graminearum, a causal agent of wheat head blight. In a previous study, FgPAL1 was found to be up-regulated in the Fgama1 mutant and important for ascosporogenesis. However, the biological function of this well-conserved gene in filamentous ascomycetes is not clear. In this study, we characterized its functions in growth, differentiation, and pathogenesis. The Fgpal1 mutant had severe growth defects and often displayed abnormal hyphal tips. It was defective in infectious growth in rachis tissues and spreading in wheat heads. The Fgpal1 mutant produced conidia with fewer septa and more nuclei per compartment than the wild type. In actively growing hyphal tips, FgPal1-GFP mainly localized to the subapical collar and septa. The FgPal1 and LifeAct partially co-localized at the subapical region in the interdependent manner. The Fgpal1 mutant was normal in meiosis with eight nuclei in developing asci but most asci were aborted. Taken together, our results showed that FgPal1 plays a role in maintaining polarized tip growth and coordination between nuclear division and cytokinesis, and it is also important for infectious growth and developments of ascospores by the free cell formation process. This article is protected by copyright. All rights reserved.

2.
Exp Biol Med (Maywood) ; : 1535370220963197, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33023330

RESUMO

IMPACT STATEMENT: In this study, we explored the expression profile of lncRNA in HCC tumor tissues and paracancerous tissues using microarray assays. Furthermore, a new lncRNA (lnc-ATG9B-4) was identified, which was about 3.5 times more expressed in tumor tissues than in paracancerous tissues. Through clinicopathological analysis, lnc-ATG9B-4 was determined to be related to the tumorous size, TNM stages, portal vein tumor thrombus (PVTT), the tumor capsule, metastasis, and the degree of differentiation. Lnc-ATG9B-4 promoted the proliferation, invasion, as well as migration of the HCC cells by upregulating the expression of CDK5. Here, we further exploited the molecular mechanisms of lnc-ATG9B-4 to screen new drug intervention targets for recurrence and metastasis of HCC.

3.
J Am Chem Soc ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33026224

RESUMO

Fractals are of fundamental importance in science and technology. Theoretical simulations indicate that Sierpinski triangles (STs) possess specific optical and electronic properties. To study their properties and uncover their potential applications, it is necessary to pack STs into large-scale two-dimensional crystalline structures. Here, a series of ordered structures consisting of ST units are successfully constructed on gold surfaces through coordination between 1,3-bis(4-pyridyl) benzene molecules and Fe atoms. Crystals of STs are characterized by scanning tunneling microscopy. K-map analysis explains the structural formation mechanism, which is further verified by density functional theory calculations. The molecular free diffusion and nice structure matching between STs and gold surfaces play important roles in the formation of crystals of STs.

4.
Biomater Sci ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33026364

RESUMO

Peptides have shown great potential in cancer treatment due to their good biocompatibility and low toxicity. However, the bioavailability and adverse immune response of peptides limit their further translation from bench to bedside. Over the past few decades, various peptide-based nanomaterials have been developed for drug delivery and cancer treatment. Compared with therapeutic peptides alone, self-assembled peptide nanomaterials have obvious advantages, such as improved stability and biodistribution for high-performance cancer therapy. In this review, we have described the synthesis, self-assembly and the anti-cancer application of therapeutic peptides and their conjugates, particularly polymer-peptide conjugates (PPCs).

5.
Nanotechnology ; 31(50): 505708, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33021234

RESUMO

A graphene oxide (GO) membrane can be easily made by filtering a GO solution onto a supporting layer, and such a membrane is effective at adsorbing ions. But low flux and a high work pressure become an obstacle for its application in wastewater treatment. In this study, a positively charged mixture of carbon nanotubes and chitosan (CNTS) served as an interlayer to improve the GO membrane's flux. The three-layer membrane is known as MCG, while one without an interlayer is known as MG. For MCG and MG with the same GO load, the water flux of MCG reaches 2-8 times larger than that of MG. A better water permeability is consistently detected for MCG, with a contact angle descent speed of 3.3°/s, which is significantly faster than that of MG (0.5°/s). The ion rejections of MCG and MG are mostly attributed to GO adsorption, which stay at the same level. The flux varies with GO load, CNTS load and membrane dryness, while the ion rejection is correlated with the GO load. Optimized membrane fabrication conditions are suggested as being a CNTS load of 0.72 g m-2 and a GO load of 0.4 g m-2. A 'gap' mechanism is suggested to explain the interlayer effects. The rougher interlayer surface produces gaps between the GO and CNTS layers, which results in the faster water permeation and higher flux of MCG. These results demonstrate that it is possible to fabricate high flux GO membranes by adding a controlled-roughness interlayer.

6.
Eur J Dermatol ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33021475

RESUMO

BACKGROUND: The efficacy and safety of secukinumab, an interleukin-17 inhibitor, as systemic treatment for patients with moderate-to-severe psoriasis have been demonstrated, but real-world data pertaining to this is limited in China. OBJECTIVE: To evaluate the efficacy and safety of secukinumab in clinical practice in Chinese psoriasis patients with or without psoriatic arthritis (PsA) and identify potential baseline factors that affect the response of patients to secukinumab treatment. MATERIALS AND METHODS: Data from 81 patients treated with secukinumab for at least 16 weeks were analysed in a retrospective observational study. RESULTS: After 16 weeks of treatment with secukinumab, 91.1%, 73%, and 38.3% of patients achieved a PASI 75 (75% improvement based on the Psoriasis Area and Severity Index), PASI 90, and PASI 100, respectively. A significant improvement in the quality of life of patients was also observed. Notably, baseline factors, such as young age, lower BMI, no scalp involvement and absence of concomitant PsA, were associated with better clinical response to secukinumab. Approximately 42% of patients (34/81) experienced adverse events, of which the most common was pruritus. CONCLUSIONS: The results demonstrated that secukinumab appears to be an effective treatment alternative for the majority of Chinese plaque psoriasis patients. Baseline factors, including age, BMI, scalp involvement and concomitant presence of PsA, were associated with response to secukinumab.

7.
Insect Sci ; 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33037856

RESUMO

Chitin deacetylases (CDAs, including CDA1 and CDA2) are considered key enzymes for body cuticle formation and tracheal morphogenesis in various insect species. However, their functions in the formation of the cuticular intima of the foregut and hindgut are unclear. Here, we investigated the roles of their respective genes LmCDA1 and LmCDA2 in this process, in the hemimetabolous insect Locusta migratoria. Transcripts of LmCDA1 and LmCDA2 were highly expressed both before and after molting in the foregut. In the hindgut, their expression was high only before molting. In both the foregut and hindgut, LmCDA1 protein was localized in the basal half of the chitin matrix (procuticle), whereas LmCDA2 was detected in the upper half of the procuticle. Knockdown of LmCDA1 by RNA interference (RNAi) in fifth-instar nymphs caused no visible defects of the hindgut cuticle. By contrast, the chitinous lamellae of the cuticular intima in the foregut of knockdown animals were less compact than in control animals. RNAi against LmCDA2 led to thickening of both the foregut and hindgut cuticles, with a greater number of thinner laminae than in the respective control cuticles. Taken together, our results show that LmCDA1 and LmCDA2 have distinct, but overlapping, functions in chitin organization in the foregut cuticle. However, in the hindgut, this process seems independent of LmCDA1 activity but requires LmCDA2 function. Thus, the CDAs reflect tissue-specific differences in cuticular organization and function, which need further detailed molecular and histological analyses for full comprehension. This article is protected by copyright. All rights reserved.

8.
Cardiovasc Ther ; 2020: 7172052, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042224

RESUMO

Background: We provide an updated meta-analysis with detailed information on a combination of TCM and routine treatment. Methods: Retrieve appropriate articles with no language restrictions on keywords until 8 July 2019 in an electronic database. All trajectories are screened according to certain criteria. The quality of certified research was also evaluated. We made a detailed record of the results of the measurement. Meta-analysis was carried out by using the Revman 5.3 software. Results: Sixty-seven RCTs were included, and 6594 subjects were analyzed. Compared with routine treatment, the total effective rate (TER) of TCM combined with routine treatment was improved, and the recovery of stroke was also significantly accelerated. Regulation of blood lipids by notably shrinking the contents of TC, TG, and LDL and enhancing the levels of HDL. The levels of serum hs-CRP, WHV, and WLV decreased significantly, indicating that the expression of thrombomodulin was decreased after the comprehensive treatment of traditional Chinese medicines (TCMs). The combination of TCM treatment could enhance the protection of neural function by decreasing the NIHSS scoring while increasing the BI scoring. Paeoniae Radix Rubra, Angeticae Sinensis Radix, etc., can effectively improve the clinical symptoms of stroke convalescent patients and promote the recovery of neurological function. ACU of Baihui, Renzhong, etc., can improve the clinical rehabilitation effect of patients. However, our findings must be handled with care because of the small sample size and low quality of clinic trials cited. Other rigorous and large-scale RCTs are in need to confirm these results. Conclusion: A combination of TCM and routine treatment in the treatment of stroke could improve TER, and it is beneficial to the rehabilitation of patients in the recovery period of apoplexy. These effects can be mediated by a combination of several mechanisms. Nevertheless, due to the limitations of this study, these results should be handled with caution.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33064318

RESUMO

Multidimensional item response theory (MIRT) is widely used in assessment and evaluation of educational and psychological tests. It models the individual response patterns by specifying a functional relationship between individuals' multiple latent traits and their responses to test items. One major challenge in parameter estimation in MIRT is that the likelihood involves intractable multidimensional integrals due to the latent variable structure. Various methods have been proposed that involve either direct numerical approximations to the integrals or Monte Carlo simulations. However, these methods are known to be computationally demanding in high dimensions and rely on sampling data points from a posterior distribution. We propose a new Gaussian variational expectation--maximization (GVEM) algorithm which adopts variational inference to approximate the intractable marginal likelihood by a computationally feasible lower bound. In addition, the proposed algorithm can be applied to assess the dimensionality of the latent traits in an exploratory analysis. Simulation studies are conducted to demonstrate the computational efficiency and estimation precision of the new GVEM algorithm compared to the popular alternative Metropolis-Hastings Robbins-Monro algorithm. In addition, theoretical results are presented to establish the consistency of the estimator from the new GVEM algorithm.

11.
Environ Chem Lett ; : 1-12, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33024427

RESUMO

The coronavirus disease 2019 (COVID-19) has brought speculations on possible transmission routes of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causal agent of the pandemic. Air pollution has been linked to increased risks of COVID-19 infection and mortality rates in regions with poor air quality, yet no retrospective study has been reported on foodborne transmission of COVID-19. While studies have shown that low temperature could dramatically prolong the persistence on SARS-CoV-2 and other coronaviruses, frozen and refrigerated foods have been widely overlooked as potential vectors in policy frameworks and risk mitigation strategies. Food transmission evidence has been disclosed in China early July 2020 by the detection of SARS-CoV-2 on frozen foods, including their packaging materials and storage environments, with two re-emergent outbreaks linked to contaminated food sources. The contamination risk is augmented by a complex farm-to-table process, which favors exposure to food workers and ambient environments. Moreover, the food cold-chain also promotes contamination because laboratory studies showed that SARS-CoV-2 remained highly stable under refrigerated, at 4 °C, and freezing conditions, from - 10 to - 80 °C, on fish, meat, poultry, and swine skin, during 14-21 days. While data are lacking on long-term survival and infectivity under these conditions, ample evidence has been shown on other coronaviruses, including SARS-CoV-1. We therefore hypothesize that contaminated cold-storage foods may present a systematic risk for SARS-CoV-2 transmission between countries and regions. Here, we review the evidence, risk factors, current policy and knowledge gaps, on food contamination and foodborne transmission of SARS-CoV-2.

12.
Invest Ophthalmol Vis Sci ; 61(12): 6, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33027505

RESUMO

Purpose: Affecting children by age 3, primary congenital glaucoma (PCG) can cause debilitating vision loss by the developmental impairment of aqueous drainage resulting in high intraocular pressure (IOP), globe enlargement, and optic neuropathy. TEK haploinsufficiency accounts for 5% of PCG in diverse populations, with low penetrance explained by variable dysgenesis of Schlemm's canal (SC) in mice. We report eight families with TEK-related PCG, and provide evidence for SVEP1 as a disease modifier in family 8 with a higher penetrance and severity. Methods: Exome sequencing identified coding/splice site variants with an allele frequency less than 0.0001 (gnomAD). TEK variant effects were assayed in construct-transfected HEK293 cells via detection of autophosphorylated (active) TEK protein. An enucleated eye from an affected member of family 8 was examined via histology. SVEP1 expression in developing outflow tissues was detected by immunofluorescent staining of 7-day mouse anterior segments. SVEP1 stimulation of TEK expression in human umbilical vascular endothelial cells (HUVECs) was measured by TaqMan quantitative PCR. Results: Heterozygous TEK loss-of-function alleles were identified in eight PCG families, with parent-child disease transmission observed in two pedigrees. Family 8 exhibited greater disease penetrance and severity, histology revealed absence of SC in one eye, and SVEP1:p.R997C was identified in four of the five affected individuals. During SC development, SVEP1 is secreted by surrounding tissues. SVEP1:p.R997C abrogates stimulation of TEK expression by HUVECs. Conclusions: We provide further evidence for PCG caused by TEK haploinsufficiency, affirm autosomal dominant inheritance in two pedigrees, and propose SVEP1 as a modifier of TEK expression during SC development, affecting disease penetrance and severity.

14.
J Asian Nat Prod Res ; : 1-6, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33030048

RESUMO

Two new dibenzyl derivatives, dendrocandins V-W (1-2), together with six known compounds (3-8), have been isolated from the dried stems of Dendrobium catenatum. Their structures were mainly elucidated on the basis of HRESIMS, one- and two-dimensional NMR techniques. The isolated compounds 5-8 were evaluated in vitro for their antioxidant and hypoglycemic activities. Compound 8 showed moderate potent DPPH scavenging activity with IC50 value of 34.45 ± 1.07 µM. And compounds 5, 7-8 exhibited significant ABTS radical scavenging activities with IC50 values of 10.03 ± 0.88, 5.32 ± 1.13 and 9.01 ± 1.39 µM. Compounds 6-7 showed potent α-glucosidase inhibitory activities with IC50 values of 36.05 ± 0.67 and 159.59 ± 0.86 µM.

15.
J Int Med Res ; 48(10): 300060520962291, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33050757

RESUMO

OBJECTIVE: To investigate whether the combination of D-dimer and simplified pulmonary embolism severity index (sPESI) could improve prediction of in-hospital death from pulmonary embolism (PE). METHODS: Patients with PE (n = 272) were divided into a surviving group (n = 249) and an in-hospital death group (n = 23). RESULTS: Compared with surviving patients, patients who died in hospital had significantly higher rates of hypotension and tachycardia, reduced SaO2 levels, elevated D-dimer and troponin T levels, higher sPESI scores, and were more likely to be classified as high risk. Elevated D-dimer levels and high sPESI scores were significantly associated with in-hospital death. Using thresholds for D-dimer and sPESI of 3.175 ng/mL and 1.5, respectively, the specificity for prediction of in-hospital death was 0.357 and 0.414, respectively, and the area under the receiver operating characteristic curve (AUC) was 0.665 and 0.668, respectively. When D-dimer and sPESI were considered together, the specificity for prediction of in-hospital death increased to 0.838 and the AUC increased to 0.74. CONCLUSIONS: D-dimer and sPESI were associated with in-hospital death from PE. Considering D-dimer levels together with sPESI can significantly improve the specificity of predicting in-hospital death for patients with PE.

16.
AJR Am J Roentgenol ; : 1-9, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33052741

RESUMO

OBJECTIVE. The purpose of this study was to develop an effective nomogram and artificial neural network (ANN) model for predicting recurrent hemoptysis after bronchial artery embolization (BAE). MATERIALS AND METHODS. The institutional ethics review boards of the two participating hospitals approved this study. Patients with hemoptysis who were treated with BAE were allocated to either the training cohort (Hospital A) or the validation cohort (Hospital B). The predictors of recurrent hemoptysis were identified by univariable and multivariable analyses in the training cohort. A nomogram and ANN model were then developed, and the accuracy was validated by the Harrell C statistic and ROC curves in both the training and validation cohorts. RESULTS. A total of 242 patients (training cohort, 141; validation cohort, 101) were enrolled in this study. The univariable and multivariable analyses revealed that age of 60 years old or older (hazard ratio [HR], 3.921; 95% CI, 1.267-12.127; p = 0.018), lung cancer (HR, 18.057; 95% CI, 4.124-79.068; p < 0.001), bronchial-pulmonary shunts (HR, 11.981; 95% CI, 2.593-55.356; p = 0.001), and nonbronchial systemic artery involvement (HR, 4.194; 95% CI, 1.596-11.024; p = 0.004) were predictors of recurrent hemoptysis. The developed nomogram and ANN model had high accuracy, with a Harrell C statistic of 0.849 (95% CI, 0.778-0.919) internally (for the training cohort) and 0.799 (95% CI, 0.701-0.897) externally (for the validation cohort). The optimal cutoff value of the recurrent hemoptysis risk was 0.16. CONCLUSION. The nomogram and ANN model could effectively predict the risk for recurrent hemoptysis after BAE. Further interventions should be considered for patients with a high suspicion of risk (> 0.16) according to the nomogram.

17.
Zootaxa ; 4801(3): zootaxa.4801.3.2, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-33056654

RESUMO

This paper describes two new species of the family Pachylaelapidae, Onchodellus menglaensis sp. nov. and O. quattuorspinous sp. nov., from the earth-boring dung beetles, Enoplotrupes sinensis Hope (Scarabaeoidea: Geotrupidae), collected from Mengla County, Yunnan Province, China. An identification key to the Chinese species of the genus Onchodellus (females) is provided.

18.
Appl Radiat Isot ; 167: 109426, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-33039760

RESUMO

A method for preparing 125I brachytherapy seeds is presented. Carbon bars were used as the substrates, on which a silver coating was deposited by electroless plating, and then, 125I was adsorbed by iodinating the silver coating so as to prepare source cores. The radioactive cores were sealed individually in the titanium capsule to fabricate the 125I brachytherapy seeds. Quality control checking of the encapsulated 125I seeds for dimension, leakage and surface contamination were performed. And the 125I seeds using carbon bar as the core substrate underwent computed tomography (CT) scan and X-ray imaging to determine the visualization. This paper provides valuable experiences and data for the preparation of 125I brachytherapy seeds.

19.
J Colloid Interface Sci ; 584: 310-319, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33069029

RESUMO

The development of in vitro cell models that mimic cell behavior in organs and tissues is an approach that may have remarkable impact on drug testing and tissue engineering applications in the future. Plant-based, chemically unmodified cellulose nanofibrils (CNF) hydrogel is a natural, abundant, and biocompatible material that has attracted great attention for biomedical applications, in particular for three-dimensional cell cultures. However, the mechanisms of cell-CNF interactions and factors that affect these interactions are not yet fully understood. In this work, multi-parametric surface plasmon resonance (SPR) was used to study how the adsorption of human hepatocellular carcinoma (HepG2) cells on CNF films is affected by the different proteins and components of the cell medium. Both human recombinant laminin-521 (LN-521, a natural protein of the extracellular matrix) and poly-l-lysine (PLL) adsorbed on CNF films and enhanced the attachment of HepG2 cells. Cell medium components (glucose and amino acids) and serum proteins (fetal bovine serum, FBS) also adsorbed on both bare CNF and on protein-coated CNF substrates. However, the adsorption of FBS hindered the attachment of HepG2 cells to LN-521- and PLL-coated CNF substrates, suggesting that serum proteins blocked the formation of laminin-integrin bonds and decreased favorable PLL-cell electrostatic interactions. This work sheds light on the effect of different factors on cell attachment to CNF, paving the way for the utilization and optimization of CNF-based materials for different tissue engineering applications.

20.
Chemistry ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33044750

RESUMO

We report a green method for the synthesis of aryl selenocyanates via a three-component reaction of arylboronic acids, Se powder and TMSCN under metal-free and additive-free conditions. Remarkably , TMSCN acts as not only the substrate, but also the catalyst. Various selenaheterocycles can be also accessed with a catalytic amount of TMSCN.

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