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2.
J Dent ; : 103210, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31600535

RESUMO

OBJECTIVES: The present study examined the effects of Na+→K+ ion-exchange on the wear performance of feldspathic veneering porcelain. METHODS: Bar and disk specimens were prepared using IPS classic as the feldspathic veneering porcelain. After ion-exchange by immersion of the specimens in melted KNO3 at two temperatures for different time-periods, the bars were tested for flexural strength and Vickers surface hardness. The disks were paired with zirconia antagonists and tested with a pin-on-disk tribometer with 10 N for 70☓104 wear cycles in artificial saliva. Wear analysis of the porcelain and zirconia was performed using 3D profilometer and analysed with one-way analysis of variance and Tukey's post-hoc pairwise comparison procedures. Worn surfaces were examined with scanning electron microscopy. RESULTS: The feldspathic veneering porcelain exhibited strong time-dependent wear behaviour, with typical running-in and steady wear stages. Ion-exchange treatments at 380 °C and 440 °C both enhanced the mechanical properties, decreased the wear rates of running-in wear and steady wear. The wear performance of porcelain treated by ion-exchange at lower temperature (380 °C) was improved significantly, especially reducing the wear rate of the running-in stage. CONCLUSION: A thicker ion-exchange layer with less stress relaxation may be obtained by ion-exchange at lower exchange temperature for a long processing time. Such a protocol improves the wear performance of the porcelain effectively. CLINICAL SIGNIFICANCE: Restorations with veneering porcelain may fail prematurely due to excessive wear. It important to improve the wear performance of the porcelain. Ion-exchange has the potential to strengthen dental veneering porcelain. Understanding the effect of ion-exchange on the wear performance of porcelain provides insight improving the wear performance of these restorations.

3.
Pest Manag Sci ; 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31595658

RESUMO

BACKGROUND: Precise regulation of oogenesis is crucial to female reproduction. 70% of pests belong to lepidopteran insect, so it would be interesting to explore the highly conserved genes involved in oogenesis that do not affect growth and development. This can provide potential target genes for pest control and promote the development of insect sterility technology. RESULTS: In lepidopteran species, ovarian serine protease (Osp), which encodes a member of the serine protease family, is essential for oogenesis. In this study, we used transgenic CRISPR/Cas9 technology to obtain Osp mutants in the model lepidopteran insect Bombyx mori and in the lepidopteran agricultural pest Spodoptera litura. Sequence analysis of mutants revealed an array of deletions in Osp loci in both species. We found that the deletion of Osp resulted in female sterility, whereas male fertility was not affected. Although B. mori and S. litura mutant females mated normally, they laid fewer eggs than wild-type females and eggs did not hatch. CONCLUSION: Osp is crucial for female reproductive success in two species of Lepidoptera. As the Osp gene is highly conserved in insect species, this gene is a potential molecular target for genetic-based pest management. This article is protected by copyright. All rights reserved.

4.
Mater Sci Eng C Mater Biol Appl ; 104: 109942, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499951

RESUMO

Decellularized matrix (dECM) is isolated extracellular matrix of tissues from its original inhabiting cells, which has emerged as a promising natural biomaterial for tissue engineering, aiming at support, replacement or regeneration of damaged tissues. The dECM can be easily obtained from tissues/organs of various species by adequate decellularization methods, and mimics the structure and composition of the native extracellular matrix, providing a favorable cellular environment. In this review, we summarize the recent developments in the preparation of dECM materials, including decellularization, crosslinking and sterilization. Also, we cover the advances in the utilization of dECM biomaterials in regeneration medicine in pre-clinic and clinical trials. Moreover, we highlight those emerging medical benefits of dECM beyond tissue engineering, such as cell transplantation, in vitro/in vivo model and therapeutic cues delivery. With the advances in the preparation and broader application, the dECM biomaterials could become the gold scaffold and pharmaceutical excipients in medical sciences.

5.
Insect Biochem Mol Biol ; : 103243, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31541694

RESUMO

Sterile insect technology (SIT) is an environmentally friendly method for pest control. As part of our efforts to develop a strategy that results in engineered male-sterile strains with minimum effects on viability and mating competition, we used CRISPR/Cas9 technology to disrupt Ser2, which encodes a seminal fluid protein, in the model lepidopteran insect, Bombyx mori, and an important agricultural pest, Plutella xylostella. Disruption of Ser2 resulted in dominant heritable male sterility. Wild-type females mated with Ser2-deficient males laid eggs normally, but the eggs did not hatch. We detected no differences in other reproductive behaviors in the mutant males. These results support the conclusion that Ser2 gene is necessary for male reproductive success in diverse lepidopterans. Targeting Ser2 gene has the potential to form the basis for a new strategy for pest control.

7.
Ann Hum Genet ; 2019 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-31495922

RESUMO

Intellectual disability (ID) describes a wide range of serious human diseases caused by defects in central nervous system development and function. Some mutant genes have been found to be associated with these diseases, but not all cases can be explained, thus suggesting that other disease-causing genes have not yet been discovered. Sialic acid is involved in a number of key biological processes, including embryo formation, nerve cell growth, and cancer cell metastasis, and very recently it has been suggested that N-acetylneuraminic acid synthase-mediated synthesis of sialic acid is required for brain and skeletal development. CMP-sialic acid synthetase (CMAS) is one of four enzymes involved in NeuNAc metabolism, as it catalyzes the formation of CMP-NeuNAc. Before the present study, no links between mutations in CMAS and incidences of human ID had been reported. In the current study, we recruited a recessive nonsyndromic ID pedigree with consanguineous marriage in which all patients have typical clinical manifestations of ID. We identified the NM_018686.3:c.563G > A (p.Arg188His) substitution in CMAS as being responsible for the disease in this family. Conservation analysis, structural prediction, and enzyme activity experiments demonstrated that (p.Arg188His) influences protein dimerization and alters CMAS enzyme activity. Our results offer a new orientation for future research and clinical diagnosis.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31519019

RESUMO

We measure planar Hall effect (PHE) and longitudinal anisotropic magnetoresistance (AMR) with a magnetic field rotating in the a-b plane in the type-II Dirac semimetal PdTe2. The measured PHE and AMR curves can be fitted by the theoretical equations; however, a detailed analysis of the extracted data demonstrates that the parameter related to PHE and AMR has no relationship with the chiral anomaly due to the absence of negative longitudinal magnetoresistance (MR) when the electric and magnetic fields are parallel to each other. Meanwhile, we prove that the origin of PHE in PdTe2 is the anisotropic orbital MR. Our work suggests that negative longitudinal MR is necessary to identify chiral anomaly, and we cannot in general use PHE as a signal for the presence of the chiral anomaly in Dirac/Weyl semimetals.

9.
Nucleic Acids Res ; 47(18): 9721-9740, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31504778

RESUMO

How chromatin dynamics is regulated to ensure efficient DNA repair remains to be understood. Here, we report that the ubiquitin-specific protease USP11 acts as a histone deubiquitinase to catalyze H2AK119 and H2BK120 deubiquitination. We showed that USP11 is physically associated with the chromatin remodeling NuRD complex and functionally involved in DNA repair process. We demonstrated that USP11-mediated histone deubiquitination and NuRD-associated histone deacetylation coordinate to allow timely termination of DNA repair and reorganization of the chromatin structure. As such, USP11 is involved in chromatin condensation, genomic stability, and cell survival. Together, these observations indicate that USP11 is a chromatin modifier critically involved in DNA damage response and the maintenance of genomic stability.

10.
Elife ; 82019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31482846

RESUMO

Indian Hedgehog (IHH) signaling, a key regulator of skeletal development, is highly activated in cartilage and bone tumors. Yet deletion of Ptch1, encoding an inhibitor of IHH receptor Smoothened (SMO), in chondrocyte or osteoblasts does not cause tumorigenesis. Here, we show that Ptch1 deletion in mice Prrx1+mesenchymal stem/stromal cells (MSCs) promotes MSC proliferation and osteogenic and chondrogenic differentiation but inhibits adipogenic differentiation. Moreover, Ptch1 deletion led to development of osteoarthritis-like phenotypes, exostoses, enchondroma, and osteosarcoma in Smo-Gli1/2-dependent manners. The cartilage and bone tumors are originated from Prrx1+ lineage cells and express low levels of osteoblast and chondrocyte markers, respectively. Mechanistically, Ptch1 deletion increases the expression of Wnt5a/6 and leads to enhanced ß-Catenin activation. Inhibiting Wnt/ß-Catenin pathway suppresses development of skeletal anomalies including enchondroma and osteosarcoma. These findings suggest that cartilage/bone tumors arise from their early progenitor cells and identify the Wnt/ß-Catenin pathway as a pharmacological target for cartilage/bone neoplasms.

11.
Pest Manag Sci ; 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31389133

RESUMO

BACKGROUND: Acaricide resistance is a serious problem in spider mites. Cyflumetofen is a new complex II inhibitor, whereas pyridaben acts at complex I and has been used for decades. Although cross-resistance between cyflumetofen and pyridaben has been observed in Tetranychus cinnabarinus, the specific mechanisms at play have not yet been investigated. RESULTS: Investigation into the cross-resistance mechanisms identified five P450s, among which CYP389C16 was evaluated as the most likely candidate conferring cross-resistance. Knockdown of CYP389C16 expression via RNA interference diminished the level of cross-resistance in the cyflumetofen-resistant strain. In addition, recombinant CYP389C16 (40 pmol) effectively metabolized 25.0 ± 0.7% of cyflumetofen, 39.7 ± 1.0% of pyridaben, and 69.3 ± 3.3% of AB-1 (active de-esterified metabolite of cyflumetofen) within 2 h. In addition, hydroxylation metabolite of AB-1 was identified by HPLC-MS/MS. CONCLUSIONS: The study reveals that overexpressed CYP389C16 is involved in the cross-resistance between cyflumetofen and pyridaben in T. cinnabarinus. © 2019 Society of Chemical Industry.

12.
Pestic Biochem Physiol ; 159: 85-90, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400788

RESUMO

RNA interference (RNAi) is a potentially useful pest control method because of its high specificity. Silencing the expression of important RNAi target genes of pests will block important biological processes and reduce pest damage. Ecdysone is a unique arthropod hormone and the ecdysone receptor (EcR) is a key factor in molting pathway. We investigated the possibility that dsRNA targeting of the EcR of Tetranychus cinnabarinus (TcEcR) could effectively block development from larvae to adults. The mRNA level of TcEcR was highest in the larva stage, and 73.1% of the mites failed to survive the larva stage when TcEcR expression was silenced. Only 11.7% of T. cinnabarinus ingesting dsRNA successfully developed into adults, while 86.7% in the control succeeded in molting across each stage. RNAi significantly increased the developmental intervals of T. cinnabarinus. Under the effects of dsRNA, development times for the larva and first nymph doubled. Phenotype of body size change and death were observed during the development of T. cinnabarinus ingesting dsRNA. These findings suggest that RNAi is a potential means for the control of T. cinnabarinus. Genes in hormone pathways such as EcR are possible RNAi targets.


Assuntos
Larva/metabolismo , Interferência de RNA/fisiologia , Receptores de Esteroides/metabolismo , Tetranychidae/metabolismo , Animais , Tamanho Corporal , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , RNA de Cadeia Dupla/genética , Receptores de Esteroides/genética , Tetranychidae/crescimento & desenvolvimento
13.
J Agric Food Chem ; 67(32): 8905-8918, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31380641

RESUMO

NAC TFs play crucial roles in response to abiotic stresses in plants. Here, ZmNAC071 was identified as a nuclear located transcriptional repressor. Overexpression of ZmNAC071 in Arabidopsis enhanced sensitivity of transgenic plants to ABA and osmotic stress. The expression levels of SODs, PODs, P5CSs, and AtMYB61 were inhibited by ZmNAC071, which results in reduced ROS scavenging and proline content, increased ROS level, and water loss. Besides, the expression levels of some ABA or abiotic stress-related genes, like ABIs, RD29A, DREBs, and LEAs were also significantly inhibited by ZmNAC071. Yeast one-hybrid assay demonstrated that ZmNAC071 specifically bound to the cis-acting elements containing CGT[G/A] core sequences in the promoter of stress-related genes, suggesting that ZmNAC071 may participate in the regulation of transcription of these genes through recognizing the core sequences CGT[G/A]. These results will facilitate further studies concerning the cis-elements and downstream genes targeted by ZmNAC071 in maize.


Assuntos
Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Ácido Ascórbico/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/fisiologia , Fatores de Transcrição/genética , Zea mays/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação para Baixo/efeitos dos fármacos , Pressão Osmótica , Plantas Geneticamente Modificadas/genética , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , Fatores de Transcrição/metabolismo
14.
Transplantation ; 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31365475

RESUMO

BACKGROUND: Islet transplantation is a promising option for the treatment of type 1 diabetes. However, the current lack of practical techniques for the isolated islets preservation still hampers the advancement of life-saving islet transplantation. Islet suffers from internal or external stimuli induced oxidative stress and subsequent inflammation during preservation, which leads to disappointing outcomes regarding islet yield, survival and function. ROS overproduction is the primary cause of oxidative stress that induces islet loss and dysfunction. Thus, in this paper, we hypothesized that an endogenous antioxidant, bilirubin, that could efficiently scavenge ROS and inhibit inflammatory reactions could be beneficial for islet preservation. METHODS: Herein, we studied the effect of bilirubin on the hypothermic preserved (4°C) islets, and evaluate the islets viability, insulin secretory function, oxidative stress levels, and in vivo transplantation performance. RESULTS: Bilirubin could prevent cellular damages during short-term preservation, and maintain the co-cultured islets viability and function. The protective role of bilirubin is associated with its antioxidative ability, which dramatically increased the activities of antioxidant enzymes (SOD and GSH-Px), and decreased the levels of ROS and MDA. Diabetic mice transplanted with bilirubin preserved islets were normoglycemic for 28 days, even overmatched the diabetic mouse transplanted with fresh islets. Mice receiving bilirubin co-cultured islets required the least time to achieve normoglycemia among all groups and exhibited minimum inflammatory responses during the early transplantation stage. CONCLUSIONS: By utilizing bilirubin, we achieved highly viable and functional islets after hypothermic preservation to reverse diabetes in mice.

15.
Metab Brain Dis ; 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31410775

RESUMO

Schizophrenia is a kind of neurodevelopmental disease. Epidemiological data associates schizophrenia with prenatal exposure to famine. Relevant prenatal protein deprivation (PPD) rodent models support this result by observing decreasing prepulse inhibition, altered hippocampal morphology and impaired memory in offspring. All these abnormalities are highly consistent with the pathophysiology of schizophrenia. We developed a prenatal famine rat model by restricting daily diet of the pregnant rat to 50% of low protein diet. A metabolomics study of prefrontal cortex was performed to integrate GC-TOFMS and UPLC-QTOFMS. Thirteen controls and thirteen famine offspring were used to differentiate in PLS-DA (partial least squares-discriminate analysis) model. Furthermore, metabolic pathways and diseases were enriched via KEGG and HMDB databases, respectively. A total of 67 important metabolites were screened out according to the multivariate analysis. Schizophrenia was the most statistical significant disease (P = 0.0016) in our famine model. These metabolites were enriched in key metabolic pathways related to energy metabolism and glutamate metabolism. Based on these important metabolites, further discussion speculated famine group was characterized by higher level of oxidized damage compared to control group. We proposed that oxidative stress might be the pathogenesis of prenatal undernutrition which is induced schizophrenia.

16.
Shanghai Kou Qiang Yi Xue ; 28(2): 196-200, 2019.
Artigo em Chinês | MEDLINE | ID: mdl-31384909

RESUMO

PURPOSE: To explore the methods and characteristics of removable denture restoration in children with congenital missing teeth. METHODS: From 1998 to 2018, 61 children aging 3 to 12 years old with congenital dental deficiency were treated with removable dentures. There were 59 males and 2 females. Removable denture prostheses were designed according to the characteristics of the children and the residual teeth in the mouth. There were 42 complete dentures in 21 cases, 40 single jaw complete dentures and maxillary removable partial dentures in 20 cases and 40 removable partial dentures in upper and lower jaw, totally 61 cases and 122 dentures. RESULTS: After wearing the removable denture, the appearance, chewing and pronunciation of the children were improved significantly. CONCLUSIONS: Although the etiology of congenital tooth defect is not completely clear, children can have early denture restoration. It solves the difficulty of eating, improves appearance and pronunciation, and promotes growth and physical and mental health of children.

17.
Ecotoxicol Environ Saf ; 183: 109551, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31419701

RESUMO

Sulfate radical (SO4-) and hydroxyl radical (OH) generated from persulfate or peroxymonosulfate in AOPs have been widely used in contaminant degradation. Anthracene (ANT) can be decomposed by SO4- and OH. The processes of ANT decomposition were investigated using theoretical calculations in this paper. The initiation reactions of ANT, anthrone, anthraquinone (ATQ) and 1-hydroxylanthraquinone (1-hATQ) by two radicals are studied. The highest free energy barriers of initiation reactions are 22.30 kcal mol-1 in ATQ + SO4- reaction and 6.84 kcal mol-1 in ATQ + OH reaction. Comparing the rate constants of initiation reaction through the two radicals at 273-373 K, it can be concluded that SO4- and OH both play important roles on the initiation of ANT and anthrone at lower pH. For ATQ and 1-hATQ, OH is more important than SO4- in the initiation process, which indicates that the indirect influence of SO4- are more significant in the degradation processes of ATQ and 1-hATQ. This study provides theoretical confirmations for the mechanisms of reactions of ANT with SO4- and OH, and evaluates the importance of SO4- and OH according to the reaction rates. The work can give more insight into the degradation of PAHs by radicals.

18.
Int J Cardiol ; 296: 129-135, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31439425

RESUMO

BACKGROUND: The therapeutic potential of doxorubicin (DOX) is limited by cardiotoxicity. Rubicon is an inhibitory interacting partner of autophagy protein UVRAG. Currently, the role of Rubicon in DOX-induced cardiotoxicity is unknown. In this study, we test the hypothesis that loss of Rubicon attenuates DOX-induced cardiotoxicity. METHODS: A mouse model of acute DOX-induced cardiotoxicity was established by a single intraperitoneal injection of DOX at a dose of 20 mg/kg. Rubicon expression was detected by Western blot. Cardiac damage was determined by measuring activities of lactate dehydrogenase and myocardial muscle creatine kinase in the serum, cytoplasmic vacuolization, collagen deposition, ROS levels, ATP content and mitochondrial damage in the heart. Cardiac morphometry and function were assessed by echocardiography. Markers for autophagy, mitophagy and mitochondrial dynamics were evaluated by Western blot and real time reverse transcription polymerase chain reaction. RESULTS: Rubicon expression was reduced in the heart 16 h after DOX treatment. DOX induced accumulation of cytoplasmic vacuolization and collagen, increased serum activities of lactate dehydrogenase and myocardial muscle creatine kinase, enhanced ROS levels, reduced ATP content, pronounced mitochondrial damage and greater left ventricular wall thickness in wild type mice, which were mitigated by Rubicon deficiency. Mechanistically, loss of Rubicon improved DOX-induced impairment of autophagic flux, Parkin-mediated mitophagy and mitochondrial fission and fusion in the heart. CONCLUSIONS: Loss of Rubicon ameliorates DOX-induced cardiotoxicity through enhancement of mitochondrial quality by improving autophagic flux, mitophagy and mitochondrial dynamics. Rubicon is a potential molecular target for prevention and therapy of DOX cardiotoxicity.

19.
J Phys Chem A ; 123(36): 7828-7838, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31397571

RESUMO

Methoxyphenols, which are emitted through biomass burning, are an important species in atmospheric chemistry. In the present study, temperature-dependent aqueous-phase OH radical reactions of six methoxyphenols and two related phenols have been investigated through laser flash photolysis and the density functional theory. The rate constants obtained were in a range of (1.1-1.9) × 1010 L mol-1 s-1 with k(3-MC) > k(Cre) ≈ k(Syr) ≈ k(MEP) > k(Res) > k(3-MP) > k(2-EP) ≈ k(2-MP). We derived the parameters of these reactions from the obtained T-dependent rate constants and found a mean Arrhenius activation energy of 16.9 kJ mol-1. The diffusion rate constants were calculated for each case and compared to the measured ones. Generally, the rate constants are found to be close to fully diffusion-controlled (kdiff = (1.4-1.5) × 1010 L mol-1 s-1 for all reactions). A structure-function relationship was established through the measurement result, which could be used for predicting unknown rate constants of other phenolic compounds. All of these findings are expected to enhance the predictive capabilities of models, such as the chemical aqueous-phase radical mechanism.

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