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1.
Food Chem ; 335: 127522, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32739804

RESUMO

Effect of twin-screw extrusion on soluble dietary fiber (SDF) from sweet potato residues (SPRs) were investigated using optimized conditions, at screw speed of 180 rpm, feed rate at 17 Hz, feed moisture at 40% and extrusion temperature at 150 °C. Extruded SDF, showed higher SDF levels (9.63%-29.25%), cholesterol and sodiumcholate adsorption capacity, radical scavenging capacity, and inhibition of digestive enzymes. Moreover, extrusion effectively reduced particle size and molecularweight of SDF, modulated monosaccharide ratios, and increased water retention capacity (WRC), oil retention capacity (ORC), swelling capacity (SC) and glucose absorption capacity (GAC). Additionally, scanning electron microscopy (SEM) demonstrated decomposition of macromolecules of SDF to smaller fractions and formation of a porous morphology following extrusion. Furthermore, the extruded SDF increased thermal stability as determined by differential scanning calorimetry (DSC). Overall, the SDF from SPRs with improved functional and physiochemical properties could be used as a functional additive in diverse food products.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33064441

RESUMO

Carbonylation of nitroaromatics with CO is extensively investigated with efficient but precious group 8-10 metal-based catalysts for the productions of both industrially and academically important chemicals such as isocyanates, formamides, carbamates, ureas and several types of heterocyclic compounds. Herein, we report that rationally designed nitrogen-doped carbon nanotubes (N-CNTs) exhibit catalytic activity toward CO activation for carbonylation of nitroaromatics to benzimidazolinones and ureas. Under the optimal conditions, N-CNT-promoted intramolecular carbonylation of 2-nitroaniline (1a) with CO leads to formation of 1,3-dihydro-2H-benzo[d]imidazol-2-one in 90% yield. Moreover, an intermolecular carbonylation of nitrobenzene and aniline with CO in the presence of the N-CNT gives 70% yield of N,N'-diphenylurea. The N-CNT is also applicable to various benzimidazolinones and phenyl ureas; moreover, it can be readily reused at least 9 times for the carbonylation. The theoretical investigation based on density functional theory calculations indicates that the graphitic N of the N-CNT plays a crucial step in the 1a reduction with CO. The correlation between the structural defect and catalytic performance of the N-CNT reveals an enhanced catalytic activity of the N-CNT with its increased structural defects. This research thus represents a major breakthrough in CO activation for nitroaromatic carbonylation with environmental-friendly, low-cost, and carbon-based catalysts as a potential alternative to expensive and scarce noble-metal-based catalysts.

3.
J Neurooncol ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33030654

RESUMO

In the original publication, there are errors in Fig. 3D and Fig. 5C and are corrected as follows.

5.
Biotechnol Adv ; : 107641, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33035614

RESUMO

Red algae are important renewable bioresources with very large annual outputs. Agarose is the major carbohydrate component of many red algae and has potential to be of value in the production of agaro-oligosaccharides, biofuels and other chemicals. In this review, we summarize the degradation pathway of agarose, which includes an upstream part involving transformation of agarose into its two monomers, D-galactose (D-Gal) and 3,6-anhydro-α-L-galactose (L-AHG), and a downstream part involving monosaccharide degradation pathways. The upstream part involves agarolytic enzymes such as α-agarase, ß-agarase, α-neoagarobiose hydrolase, and agarolytic ß-galactosidase. The downstream part includes the degradation pathways of D-Gal and L-AHG. In addition, the production of functional agaro-oligosaccharides such as neoagarobiose and monosaccharides such as L-AHG with different agarolytic enzymes is reviewed. Third, techniques for the setup, regulation and optimization of agarose degradation to increase utilization efficiency of agarose are summarized. Although heterologous construction of the whole agarose degradation pathway in an engineered strain has not been reported, biotechnologies applied to improve D-Gal utilization efficiency and construct L-AHG catalytic routes are reviewed. Finally, critical aspects that may aid in the construction of engineered microorganisms that can fully utilize agarose to produce agaro-oligosaccharides or as carbon sources for production of biofuels or other value-adding chemicals are discussed.

6.
Dev Cell ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33038333

RESUMO

Motile cilia are cellular beating machines that play a critical role in mucociliary clearance, cerebrospinal fluid movement, and fertility. In the airways, hundreds of motile cilia present on the surface of a multiciliated epithelia cell beat coordinately to protect the epithelium from bacteria, viruses, and harmful particulates. During multiciliated cell differentiation, motile cilia are templated from basal bodies, each extending a basal foot-an appendage linking motile cilia together to ensure coordinated beating. Here, we demonstrate that among the many motile cilia of a multiciliated cell, a hybrid cilium with structural features of both primary and motile cilia is harbored. The hybrid cilium is conserved in mammalian multiciliated cells, originates from parental centrioles, and its cellular position is biased and dependent on ciliary beating. Furthermore, we show that the hybrid cilium emerges independently of other motile cilia and functions in regulating basal body alignment.

7.
Dev Cell ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33038334

RESUMO

In situ molecular architecture analysis of organelles and protein assemblies is essential to understanding the role of individual components and their cellular function, and to engineering new molecular functionalities. Through a super-resolution-driven approach, here we characterize the organization of the ciliary basal foot, an appendage of basal bodies whose main role is to provide a point of anchoring to the microtubule cytoskeleton. Quantitative image analysis shows that the basal foot is organized into three main regions linked by elongated coiled-coil proteins, revealing a conserved modular architecture in primary and motile cilia, but showing distinct features reflecting its specialized functions. Using domain-specific BioID proximity labeling and super-resolution imaging, we identify CEP112 as a basal foot protein and other candidate components of this assembly, aiding future investigations on the role of basal foot across different cilia systems.

8.
BMC Med Genet ; 21(1): 191, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004005

RESUMO

BACKGROUND: Central nervous system (CNS) hemangioblastomas are the most frequent cause of mortality in patients with Von Hippel-Lindau (VHL) disease, an autosomal dominant genetic disease resulting from germline mutations in the VHL tumor suppressor gene, with most mutations occurring in the exons. To date, there have been no reports of CNS hemangioblastoma cases related to pathogenic variants in intron 2 of VHL, which encodes a tumor suppressor protein (i.e., pVHL) that regulates hypoxia-inducible factor proteins. CASE PRESENTATION: We report the presence of a base substitution of c.464-1G > C and c.464-2A > G in the intron 2 of VHL causing CNS hemangioblastomas in six patients with VHL from two Chinese families. The clinical information about the two pathogentic variants has been submitted to ClinVar database. The ClinVar accession for NM_000551.3(VHL):c.464-1G > C was SCV001371687. This finding may provide a new approach for diagnosing and researching VHL-associated hemangioblastomas. CONCLUSIONS: This is the first report of a pathogenic variant at intron 2 in VHL-associated hemangioblastomas. Gene sequencing showed that not only exonic but also intronic mutations can lead to the development of CNS hemangioblastomas.

9.
Phys Chem Chem Phys ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33025988

RESUMO

The zinc-promoted silylation method is of great importance to synthesize high-performance silicon-containing arylacetylene (PSA) resins in the industry. However, it is difficult to eliminate the accompanied by-product of terminal alkenes due to the lack of mechanistic understanding of the silylation. The initiation of zinc-promoted silylation is facilitated by the interaction between zinc and phenylacetylene. Our DFT calculations indicated that the intermolecular hydrogen transfer of phenylacetylene follows an ionic pathway, which generates a phenylacetylene anion and the corresponding alkene moieties on the zinc surface. The styrene by-product is observed in this stage, with its alkene moieties desorbing as radicals into the solvent under the high reaction temperature. Three possible intermediates of surface phenylacetylene anions were proposed including PhC[triple bond, length as m-dash]C-Zn, PhC[triple bond, length as m-dash]CZnCl, and (PhC[triple bond, length as m-dash]C)2Zn. These carbanion-zinc intermediates undergo an SN2 reaction with Me3SiCl to afford the alkynylsilane on the zinc surface, which is calculated to be the rate-determining step for the zinc-promoted silylation reaction.

10.
Sci Total Environ ; 755(Pt 2): 142658, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33045597

RESUMO

Drinking water treatment plants (DWTPs) are thought to be able to remove many micropollutants including nanoplastics (NPs) and microplastics (MPs). However, few studies have focused on the water treatment process itself producing NPs and/or MPs. This paper discussed the possibility of releasing NPs and MPs from organic membranes in drinking water treatment plants. The effects of physical cleaning, chemical agents, mechanical stress, aging, and wear on the possibility of membrane breach during long-term use were analyzed. Further analysis based on membrane aging mechanisms and material properties revealed that the membrane filtration systems could release NPs/MPs to drinking water supply networks. Although the toxicity of membrane materials to human body needs further study, the action that should be taken to treat the release of NPs/MPs in DWTPs cannot be ignored: (1) in-depth study of the generation and release mechanisms of NPs/MPs; (2) reconsideration of membrane life cycle design; (3) determination of NPs/MPs concentration limits in drinking water through toxicity assessment; (4) accelerating development of biomembrane and inorganic membrane materials; and (5) unification of NPs/MPs sampling and testing standard. Accordingly, more research needs to be conducted to investigate the release of NPs and/or MPs from DWTPs.

11.
Cancer Lett ; 495: 1-11, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32949680

RESUMO

As a promising method for local tumor treatment, nanosecond pulsed electric field (nsPEF) ablation elicits a potent anti-tumor immune response. However, the mechanism of the nsPEF-mediated anti-tumor immune response and its effects on the tumor microenvironment remains unclear. Here, we demonstrated that nsPEF treatment increased the level of membrane PD-L1 in liver cancer cells. Furthermore, nsPEF induced the release of PD-L1-associated extra-cellular vesicles, leading to the dysfunction of CD8+ T cells, which could potentially be reversed by PD-L1 blockade. Biological and functional assays also demonstrated that nsPEF treatment resulted in the increased PD-L1 level and dysfunction of infiltrated CD8+ T cells in tumor tissues in vivo, indicating the long term antitumor efficacy of nsPEF treatment. A combination of nsPEF treatment and PD-L1 blockade effectively inhibited tumor growth and improved the survival of the tumor-bearing mouse. In conclusion, nsPEF treatment induced the translocation and release of PD-L1 and contributed to the dysfunction of infiltrated CD8+ T cells, resulting in tumor progression at later stages. The combination of nsPEF treatment and PD-L1 blockade is a promising therapeutic strategy for liver cancer.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32965562

RESUMO

Thermal activity and stability are important characteristics for proteases applied in the detergent, pharmaceutical, food, and other green industries. With the intent to discover thermostable novel proteases, we constructed a fosmid metagenomic library from marine sediments in the East China Sea and isolated a clone endowed with high proteolytic activity from this library. Sequence analysis of the positive subclones allowed the identification of a coding region of 1254 bp related to protease activity. The unrooted phylogenetic tree and alignment results revealed that the sequence might be derived from Anaerolineaceae bacterium and encodes a new member of the peptidase S8A subfamily with the typical catalytic triad Asp119/His150/Ser325. The fusion protein, named pF1AL2, was expressed in Escherichia coli and showed a molecular weight of 35 kDa. pF1AL2 was active in the pH range of 5.0-11.0 with an optimal pH at 10.0 and had high stability under alkaline conditions, retaining more than 95% of its activity after 24 h at pH 11.0. The optimal temperature of pF1AL2 was 80 °C, and it retained nearly 80% of its activity after 6 h at 70 °C, showing great thermal activity and stability. In addition, the enzyme had great salt tolerance (the residual activity when kept in 3 M NaCl was 40%). Its thermal activity and stability, along with its halotolerance and pH-tolerance, indicate the high potential value of pF1AL2 in industrial applications. The exploitation of pF1AL2 could lay the foundation for the development and utilization of proteases with special features from marine resources by a metagenomic strategy. KEY POINTS: • A novel protease, pF1AL2, from marine sediments, was screened out by a metagenomic strategy. • The protease pF1AL2 analyzed in silico, cloned, and characterized. • pF1AL2 had an optimal temperature of 80 °C and retained nearly 80% of activity after 6 h at 70 °C. • pF1AL2 had great tolerance for high-temperature and acid, alkaline, and high salt environments.

14.
Biomed Res Int ; 2020: 5273969, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32908897

RESUMO

As one major gynecological malignancy, endometrial cancer (EC) has been widely studied recently. However, its pathogenesis is still unclear to date. In this study, we identified differentially expressed proteins between 30 endometrial cancer tissues and 30 matched normal controls using 2D LC-MS/MS quantitative proteomics. As a result, we identified 619 differentially expressed proteins among all 2521 proteins being quantified. Further analyses suggested that the changes of fat, amino acid metabolism, peroxisome, extracellular signal, cytoskeleton, and other signaling or metabolic pathways may be closely related to the development of this cancer. Particularly, the PI3K/AKT/mTOR pathway-related molecules including PI3K and mTOR, ERK (the molecule of the ERK pathway), SPP1, and ANGPT2 (angiogenesis-related molecules) are highly associated with the pathogenesis of EC, which were reconfirmed by western blot and immunohistochemistry (IHC) analysis. In summary, our study revealed that the PI3K/AKT/mTOR pathway and tumor angiogenesis molecules contribute to the pathogenesis of endometrial cancer.

15.
Neuropharmacology ; 180: 108301, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32910952

RESUMO

Social anxiety disorder (SAD) usually onsets in childhood or adolescence and is associated with brain development and chronic family stress during this period. As an information hub, the thalamus plays a crucial role in the development of emotion processing and stress regulation. Its structural and functional lateralization have been related to mental disorders. This study examined the age-dependent asymmetry of the thalamic volume in children and adolescents with SAD. We further examined the role of the thalamic asymmetry in moderating the relationships between parental alienation, which is a main source of familial stress for children and adolescents, and anxiety symptoms in this population. Fifty-three medication-free children and adolescents with SAD and 53 typical developing controls (age: 8-17) were included. Anxiety severity was measured using the Screen for Child Anxiety-Related Emotional Disorders (SCARED). We estimated the bilateral thalamic volume and examined diagnosis effect and age-group difference on the thalamic asymmetry. We further examined the moderation of the thalamic asymmetry on the associations between scores on the parental alienation, social phobia, and total SCARED. Compared with controls, the SAD group exhibited significantly abnormal asymmetry in thalamic volume. This asymmetry became more evident in the older age group. Furthermore, this asymmetry significantly weakened the relationships between parental attachment and total SCARED score. The asymmetry of the thalamic volume and its age-group difference provide novel evidence to support brain developmental abnormalities in children and adolescents with SAD. The findings further revealed interactions between physiological and chronic stress in children and adolescents with SAD.

16.
Mol Med Rep ; 22(4): 3191-3200, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32945429

RESUMO

Hepatic fibrosis (HF) is a common complication of numerous chronic liver diseases, but predominantly results from persistent liver inflammation or injury. If left untreated, HF can progress and develop into liver cirrhosis and even hepatocellular carcinoma. However, the underlying molecular mechanisms of HF remain unknown. The present study aimed to investigate the role of 11ß­hydroxysteroid dehydrogenase­1 (11ß­HSD1) during the development of hepatic fibrosis. An experimental rat model of liver fibrosis was induced using porcine serum. 11ß­HSD1 gene expression levels and enzyme activity during hepatic fibrogenesis were assessed. 11ß­HSD1 gene knockdown using small interfering RNA and overexpression were performed in LX2­human hepatic stellate cells (HSCs). HSCs were stimulated with transforming growth factor­ß1 (TGF­ß1). Cell cycle distribution, proliferation, collagen secretion and 11ß­HSD1 gene activity in HSCs were compared before and after stimulation. As hepatic fibrosis progressed, 11ß­HSD1 gene expression and activity increased, indicating a positive correlation with typical markers of liver fibrosis. 11ß­HSD1 inhibition markedly reduced the degree of fibrosis. The cell proliferation was increased, the number of cells in the G0/G1 phase decreased and the number of cells in the S and G2/M phases increased in the pSuper transfected group compared with the N group. In addition, the overexpression of 11ß­HSD1 enhanced the TGF­ß1­induced activation of LX2­HSCs and enzyme activity of connective tissue growth factor. 11ß­HSD1 knockdown suppressed cell proliferation by blocking the G0/G1 phase of the cell cycle, which was associated with HSC stimulation and inhibition of 11ß­HSD1 enzyme activity. In conclusion, increased 11ß­HSD1 expression in the liver may be partially responsible for hepatic fibrogenesis, which is potentially associated with HSC activation and proliferation.

17.
Aging (Albany NY) ; 12(18): 17976-17989, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32960786

RESUMO

Serum uric acid is reportedly associated with thrombosis development. However, still unclear is the mechanism of high uric acid in thrombosis with the involvement of let-7c. In an aim to fill this void, we conducted this study by treating mice and human umbilical vein endothelial cells with high uric acid. Analysis indicated that let-7c was upregulated in hyperuricemia patients as well as in mice and human umbilical vein endothelial cells treated with high uric acid. Furthermore, high uric acid inhibited myocyte enhancer factor-2C, but activated nuclear factor-kappa B pathway in human umbilical vein endothelial cells. Then the targeting relationship between let-7c and myocyte enhancer factor-2C was verified. On the one hand, high uric acid shortened activated partial thromboplastin time and prothrombin time of mice and declined tissue plasminogen activator level. Additionally, the treatment prolonged thrombin time and elevated the levels of thrombosis related molecules or proteins such as Fibrinogen and D-dimer. Nevertheless, these alternations could be reversed by inhibition of let-7c and nuclear factor-kappa B pathway or overexpressing myocyte enhancer factor-2C. To sum up, our results uncovered the pro-thrombotic effect of high uric acid in mice by activating myocyte enhancer factor-2C-dependent nuclear factor-kappa B pathway via let-7c upregulation.

18.
Stereotact Funct Neurosurg ; : 1-12, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32898850

RESUMO

BACKGROUND: Brain metastasis (BM) is the most common brain malignancy and a common cause of death in cancer patients. However, the relative outcome-related advantages and disadvantages of surgical resection (SR) and stereotactic radiosurgery (SRS) in the initial treatment of BM are controversial. METHOD: We systematically reviewed the English language literature up to March 2020 to compare the efficacy of SR and SRS in the initial treatment of BM. We identified cohort studies from the Cochrane Library, PubMed, and EMBASE databases and conducted a meta-analysis following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Twenty cohort studies involving 1,809 patients were included. Local control did not significantly differ between the SR and SRS groups overall (hazard ratio [HR] 1.02, 95% confidence interval (CI) 0.64-1.64, p = 0.92; I2 = 54%, p = 0.03) or in subgroup analyses of SR plus SRS vs. SRS alone, SR plus whole brain radiation therapy (WBRT) versus SRS plus WBRT, or SR plus WBRT versus SRS alone. Distant intracranial control did not significantly differ between the SR and SRS groups overall (HR 0.78, 95% CI 0.38-1.60, p = 0.49; I2 = 61%, p = 0.03) or in subgroup analyses of SR plus SRS versus SRS alone or SR plus WBRT versus SRS alone. In addition, overall survival (OS) did not significantly differ in the SR and SRS groups (HR 0.91, 95% CI 0.65-1.27, p = 0.57; I2 = 47%, p = 0.09) or in subgroup analyses of SR plus SRS versus SRS alone, SR plus WBRT versus SRS alone or SR plus WBRT versus SRS plus WBRT. CONCLUSION: Initial treatment of BM with SRS may offer comparable local and distant intracranial control to SR in patients with single or solitary BM. OS did not significantly differ between the SR and SRS groups in people with single or solitary BM.

19.
Artigo em Inglês | MEDLINE | ID: mdl-32924219

RESUMO

The COVID-19 pandemic has taken a significant toll on people worldwide, and there are currently no specific antivirus drugs or vaccines. Herein it is a therapeutic based on catalase, an antioxidant enzyme that can effectively breakdown hydrogen peroxide and minimize the downstream reactive oxygen species, which are excessively produced resulting from the infection and inflammatory process, is reported. Catalase assists to regulate production of cytokines, protect oxidative injury, and repress replication of SARS-CoV-2, as demonstrated in human leukocytes and alveolar epithelial cells, and rhesus macaques, without noticeable toxicity. Such a therapeutic can be readily manufactured at low cost as a potential treatment for COVID-19.

20.
Opt Express ; 28(19): 27443-27458, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32988038

RESUMO

During camera calibration, targets need to be placed in the depth of field of the lens to ensure clear imaging, and they should take up proper proportions in the image. These requirements cause difficulty in many calibration scenarios, such as those involving large-field-of-view, shallow-depth-of-field, or online operation cameras. In view of the above-mentioned problems, this study proposes a high-accuracy camera calibration method, which can overcome the influence of image blur and noise and is not limited by depth of field and target size. First, a high-accuracy light-spot small target is placed closely in front of the camera, so that the target image can take up a large proportion in the whole image. In case of defocus blur, the adaptive multi-scale method is used to extract feature point coordinates at first to ensure accuracy, and the location variance of each feature point is estimated concurrently. Finally, the high-accuracy intrinsic and extrinsic parameters of the camera under test are obtained by nonlinear optimization where re-projection errors are normalized by location variances according to the Gauss-Markov theorem. Simulation and physical experiments validate the effectiveness of the proposed method.

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