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1.
J Prosthet Dent ; 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32402439

RESUMO

STATEMENT OF PROBLEM: The corrosive effects of oral fluoride products on titanium have been reported, and chronic fluorosis, which causes hyperfluoemia, is one of the world's health problems. Nevertheless, the relationship between high serum fluoride and corrosion on the titanium surface, which might have adverse effects on titanium implant osseointegration, has not been elucidated. PURPOSE: The purpose of this in vitro study was to investigate the corrosion behavior of pure titanium exposed to high serum fluoride with different pH values based on surface analysis. MATERIAL AND METHODS: Pure titanium specimens, exposed to different electrolytes with 0.04 and 0.4 ppm NaF at pH 7.3 and 5.0 values, were examined for surface microstructure by using scanning electron microscopy (SEM) and for surface element composition with X-ray photoelectron spectroscopy (XPS). The corrosion behavior and metal ion release of specimens immersed in the Hanks' balanced salt solution (HBSS) containing 0.04 and 0.4 ppm serum fluoride concentrations (NaF) at 7.3 and 5.0 pH values were measured by electrochemical impedance spectroscopy (EIS) and inductively coupled plasma atomic emission spectrometry (ICP-AES). RESULTS: Pitting holes were observed on pure titanium surfaces exposed to high serum fluoride. The surfaces became rougher with the increase of serum fluoride concentration, especially under acidic conditions. XPS analysis revealed a reduction of dominant titanium dioxide (TiO2) on the pure titanium surface under serum fluoride exposure, corresponding to an increase in the relative level of F. EIS data showed an active corrosion behavior of pure titanium exposed to high serum fluoride and gradually decreased corrosion resistance with increasing concentration of serum fluoride, which was more severe under acidic conditions. The release of titanium ions was also induced by high serum fluoride and acidic conditions. CONCLUSIONS: High serum fluoride had a negative influence on the corrosion behavior of pure titanium. The titanium oxide film barrier could be broken down in the fluoride ions condition, and the corrosion resistance of pure titanium decreased with the increasing concentration of serum fluoride. The increased corrosion susceptibility of pure titanium accelerated the release of titanium ions after exposure to high serum fluoride; this was more pronounced in an acidic environment.

2.
Mol Cell Probes ; : 101592, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32389788

RESUMO

Obesity-associated hypertension induces organ damage and it is important to identify the protein responsible for initiating organ damage involves a complex pathological mechanism which most likely consists of multiple players that alters the normal physiology. The present study focuses mainly on identifying the role of HMGB1 in cardiac and renal tissue damage following obesity-induced hypertension. Following high-fat diet and leptin injection, mice developed obesity-induced initial hypertension and critical hypertension after 4 and 9 months, respectively. Histology, Immunohistochemistry, Western blotting, and siRNA were used for analysis. Histopathological analysis showed that the compact nature of cardiac and renal tissues began to loosen at the initial stages of organ damage. At the advanced stages of organ damage, cardiac tissue hardened, and renal tissue exhibited fibrosis development. Immunohistochemistry and western blotting studies revealed that HMGB1 expression was elevated in cardiac and renal tissues following initial hypertension-induced organ damage, but its expression was downregulated at critical stages of organ damage. The inflammatory marker COX2 exhibited a gradually upregulated expression pattern as organ damage progressed. Silencing of HMGB1 expression after the development of initial organ damage significantly reduced COX2 expression, but its suppression at the advanced stage of organ damage was associated with increased COX2 expression. Our study shows that HMGB1 plays a key role in initiating organ damage following obesity-induced hypertension, and that once damage reaches a certain level, HMGB1 expression is downregulated.

4.
Toxicol Lett ; 330: 23-29, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32387388

RESUMO

Diisodecyl phthalate (DIDP) is one of synthetic phthalate plasticizers. It is widely used in plastic products and is a potential endocrine disruptor. However, the effects of DIDP on fetal testicular cell development remain unclear. The objective of the present study was to determine the effects of DIDP on fetal testis development in rats after in utero exposure. Sprague Dawley dams were randomly divided into 5 groups and were daily gavaged with DIDP (0, 10, 100, 500, and 1000 mg/kg body weight) from gestational day 14-21. Serum testosterone levels, fetal Leydig cell number and distribution, testicular gene and protein expression in male pups were examined. DIDP decreased serum testosterone levels at 1000 mg/kg (1.37 ± 0.40 ng/mL, mean ± SE) when compared to the control level (3.14 ± 0.60 ng/mL). DIDP did not affect numbers of Leydig and Sertoli cells. DIDP significantly induced abnormal aggregation of fetal Leydig cells and increased the incidence of multinucleated gonocytes at 1000 mg/kg. Furthermore, DIDP down-regulated expression of Star, Cyp11a1, Hsd17b3, and Insl3 in fetal Leydig cells at 1000 mg/kg and Sox9 in Sertoli cells at 1000 mg/kg. In conclusion, the current study indicates that in utero exposure to high-dose DIDP disrupts the development of fetal testicular cells, thus affecting the male reproductive system.

5.
Mol Metab ; : 101011, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32416314

RESUMO

BACKGROUND: In response to energy abundant or deprived conditions, nutrients and hormones activate hypothalamic pathways to maintain energy and glucose homeostasis. The underlying CNS mechanisms, however, remain elusive in rodents and humans. SCOPE OF REVIEW: Here, we first discuss brain glucose sensing mechanisms in the presence of a rise or fall of plasma glucose levels, and highlight defects in hypothalamic glucose sensing disrupts in vivo glucose homeostasis in high-fat fed, obese, and/or diabetic conditions. Second, we discuss brain leptin signalling pathways that impact glucose homeostasis in glucose-deprived and excessed conditions, and propose that leptin enhances hypothalamic glucose sensing and restores glucose homeostasis in short-term high-fat and/or uncontrolled diabetic conditions. MAJOR CONCLUSIONS: In conclusion, we believe basic studies that investigate the interaction of glucose sensing and leptin action in the brain will address the translational impact of hypothalamic glucose sensing in diabetes and obesity.

6.
Insect Sci ; 2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-32452090

RESUMO

The ladybird Harmonia axyridis is an insect that exhibits pupal attachment to plants, which facilitates development and environmental adaptation. The cremaster is highly specialised for this behaviour. However, the underlying molecular regulation of the cremaster remains unclear; therefore, we performed experiments to investigate the transcriptional regulation of cremaster development. First, we examined the morphological structure of the cremaster to reveal its function in pupal attachment of H. axyridis. Next, we analysed the Hox gene Ha-Abd-B using RNAi to determine its function in regulating cremaster formation; Ha-Abd-B up-regulation promoted effective pupal attachment, whereas successful RNAi caused severe down-regulation of this gene, and pupae were unable to attach. Furthermore, successful RNAi and subsequent Ha-Abd-B down-regulation caused phenotypic changes in cremaster structure, including its complete disappearance from some individuals. Finally, we observed unique development of the cremaster and dynamic expression of Ha-Abd-B during pre-pupal development; consequently, we hypothesised that there was specific pre-pupal development of the cremaster. Overall, based on these results, the specialised cremasteric structure located on the posterior side of H. axyridis was determined to be a key organ for pupal attachment. Cremaster identification in H. axyridis is regulated by Ha-Abd-B and exhibits preferential development. Pupal attachment of H. axyridis reveals an environmental adaptation of this species; thus, this study and future molecular studies will help determine the role of Hox genes in regulation of insect attachment and further our understanding of the multiple functions of Hox genes. This article is protected by copyright. All rights reserved.

7.
Environ Microbiol ; 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32441046

RESUMO

Antibiotic-resistant Vibrio alginolyticus poses a big challenge to human health and food safety. It's urgently needed to understand the mechanisms underlying antibiotic resistance to develop effective approaches for the control. Here we explored the metabolic difference between gentamicin-resistant V. alginolyticus (VA-RGEN ) and gentamicin-sensitive V. alginolyticus (VA-S), and found that the reactive oxygen species (ROS) generation was altered. As compared to VA-S, the ROS content in VA-RGEN was reduced due to the decreased generation and increased breakdown of ROS. The decreased production of ROS was attributed to the decreased central carbon metabolism, which is associated with the resistance to gentamicin. As such a mechanism, we exogenously administrated VA-RGEN with the glucose that activated the central carbon metabolism and promoted the generation of ROS, but decreased the breakdown of ROS in VA-RGEN . The gentamicin-mediated killing was increased with the elevation of the ROS level by a synergistic effect between gentamicin and exogenous glucose. The synergistic effect was inhibited by thiourea, a scavenger of ROS. These results reveal a reduced ROS-mediated antibiotic resistance mechanism and its reversal by exogenous glucose. This article is protected by copyright. All rights reserved.

9.
J Asian Nat Prod Res ; : 1-11, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32406756

RESUMO

Two series of sulfonate derivatives of carvacrol and thymol were synthesized and screened in vitro for their anti-oomycete activity against Phytophthora capsici, respectively. Among all of 32 derivatives, five compounds 3a, 4a, 4k, 3n, and 4n exhibited more potent anti-oomycete activity against P. capsici with EC50 values of 66.66, 62.94, 68.65, 61.24, and 52.91 mg/L, respectively. This suggested that introduction of different substitutions at the hydroxyl position of 1/2 could have remarkable effect on anti-oomycete activity. Overall, when R1 = isopropyl and R2 = methyl, the anti-oomycete activities of the compounds were higher than that of the corresponding compounds of R1 = methyl and R2 = isopropyl.[Formula: see text].

10.
Medicine (Baltimore) ; 99(18): e20035, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32358383

RESUMO

INTRODUCTION: Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) involves a severe inflammatory response. Systemic glucocorticoids are very important for the treatment of the acute exacerbation period; however, their use causes serious adverse effects. There is still no evidence on whether traditional Chinese medicine (TCM) can be used to reduce the dosage of systemic glucocorticoids in the treatment of patients with AECOPD. METHODS: In this trial, we plan to enroll 204 eligible patients with AECOPD who will be randomly assigned to receive TCM or a placebo. The effect of TCM in the treatment of patients with AECOPD will be measured by the dosage of systemic glucocorticoids (at which COPD assessment test [CAT] scores improve by 50%). Safety will also be assessed. TRIAL REGISTRATION: ChiCTR2000029568.


Assuntos
Glucocorticoides/uso terapêutico , Medicina Tradicional Chinesa/métodos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Adulto , Idoso , Progressão da Doença , Relação Dose-Resposta a Droga , Feminino , Glucocorticoides/administração & dosagem , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Medicina Tradicional Chinesa/efeitos adversos , Pessoa de Meia-Idade , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Qualidade de Vida , Projetos de Pesquisa , Testes de Função Respiratória
11.
Technol Health Care ; 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32364150

RESUMO

BACKGROUND: The risk factors of hypertensive disorders in pregnancy (HDP) could be summarized into three categories: clinical epidemiological factors, hemodynamic factors and biochemical factors. OBJECTIVE: To establish models for early prediction and intervention of HDP. METHODS: This study used the three types of risk factors and Support Vector Machine (SVM) to establish prediction models of HDP at different gestational weeks. RESULTS: The average accuracy of the model was gradually increased when the pregnancy progressed, especially in the late pregnancy 28-34 weeks and ⩾ 35 weeks, it reached more than 92%. CONCLUSION: Multi-risk factors combined with dynamic gestational weeks' prediction of HDP based on machine learning was superior to static and single-class conventional prediction methods. Multiple continuous tests could be performed from early pregnancy to late pregnancy.

12.
Technol Health Care ; 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32364151

RESUMO

BACKGROUND: Fetal ECG can be obtained in a non-invasive manner to monitor fetal growth status. OBJECTIVE: In this study, a fetal heart rate calculation system was proposed, which consists of the fetal ECG recorder (MF-HOLTER) and the fetal ECG monitoring software (FECG-MS). The abdomen electrocardiogram (AECG) of pregnant woman is acquired through the MF-HOLTER. The FECG-MS packs the AECG data and calls the fetal ECG separation algorithm to obtain the separated FECG and the fetal QRS (FQRS) position. The fetal heart rate (FHR) is further obtained by calculating the R-R interval value. At the same time, this study proposed a FQRS position correction algorithm to calculate the correct FHR value. METHOD: In order to verify the accuracy of the FHR calculation, the ECG signal of FLUKE's PS320 FETAL SIMULATOR and clinical data were simultaneously tested. RESULTS: The accuracy rate is over 98% in processing the simulator's data. In processing clinical data, the FHR values obtained by both the system proposed in this study and Monica AN24 are very close, and the difference is less than 1 bpm. CONCLUSION: The results show that the fetal heart rate calculation system is accurate and stable, and has a positive application value and prospect.

13.
Plant Dis ; : PDIS08191744RE, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357118

RESUMO

During biological indexing for viruses in citrus trees, in a collection of Symons sweet orange (SSO) (Citrus sinensis L. Osbeck) graft inoculated with bark tissues of citrus trees from the Punjab Province in Pakistan, several SSO trees exhibited leaf symptoms of vein yellowing and mottle. High-throughput sequencing by Illumina of RNA preparation depleted of ribosomal RNAs from one symptomatic tree, followed by BLAST analyses, allowed identification of a novel virus, tentatively named citrus yellow mottle-associated virus (CiYMaV). Genome features of CiYMaV are typical of members of the genus Mandarivirus (family Alphaflexiviridae). Virus particles with elongated flexuous shape and size resembling those of mandariviruses were observed by transmission electron microscopy. The proteins encoded by CiYMaV share high sequence identity, conserved motifs, and phylogenetic relationships with the corresponding proteins encoded by Indian citrus ringspot virus (ICRSV) and citrus yellow vein clearing virus (CYVCV), the two current members of the genus Mandarivirus. Although CYVCV is the virus most closely related to CiYMaV, the two viruses can be serologically and biologically discriminated from each other. A reverse-transcription PCR method designed to specifically detect CiYMaV revealed high prevalence (62%) of this virus in 120 citrus trees from the Punjab Province, Pakistan, where the novel virus was found mainly in mixed infection with CYVCV and citrus tristeza virus. However, a preliminary survey on samples from 200 citrus trees from the Yunnan Province, China failed to detect CiYMaV in this region, suggesting that the molecular, serological, and biological data provided here are timely and can help to prevent the spread of this virus in citrus-producing countries.

14.
Artigo em Inglês | MEDLINE | ID: mdl-32346936

RESUMO

Hierarchical FeCoS2 -CoS2 double-shelled nanotubes have been rationally designed and constructed for efficient photocatalytic CO2 reduction under visible light. The synthetic strategy, engaging the two-step cation-exchange reactions, precisely integrates two metal sulfides into a double-shelled tubular heterostructure with both of the shells assembled from ultrathin two-dimensional (2D) nanosheets. Benefiting from the distinctive structure and composition, the FeCoS2 -CoS2 hybrid can reduce bulk-to-surface diffusion length of photoexcited charge carriers to facilitate their separation. Furthermore, this hybrid structure can expose abundant active sites for enhancing CO2 adsorption and surface-dependent redox reactions, and harvest incident solar irradiation more efficiently by light scattering in the complex interior. As a result, these hierarchical FeCoS2 -CoS2 double-shelled nanotubes exhibit superior activity and high stability for photosensitized deoxygenative CO2 reduction, affording a high CO-generating rate of 28.1 µmol h-1 (per 0.5 mg of catalyst).

15.
Mol Med Rep ; 21(4): 1941-1949, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32319620

RESUMO

DNA methylation and hydroxymethylation are the most common epigenetic modifications associated with the cell cycle and the inflammatory response. The present study aimed to investigate the role of 5­hydroxymethyl­cytosine (5­hmC) and ten­eleven translocation­2 (TET2) in keratinocytes. Following TET2 knockdown, dot blot analysis was performed to assess the levels of 5­hmC in keratinocytes, using HaCaT cells. Subsequently, the viability and cell cycle of HaCaT cells were assessed by MTT, Cell Counting Kit­8 assay and flow cytometric assays. Cyclin­dependent kinase inhibitor 2A and proinflammatory cytokine protein and mRNA expression levels were also detected. The present results suggested that TET2 may play an important role in regulating cellular proliferation by mediating DNA hydroxymethylation in HaCaT cells. In addition, TET2 knockdown decreased the production of proinflammatory cytokines, including lipocalin 2, S100 calcium binding protein A7, matrix metallopeptidase 9, C­X­C motif chemokine ligand 1, interferon regulatory factor 7 and interleukin­7 receptor. The present study suggested that TET2 regulated cell viability, apoptosis and the expression of inflammatory mediators in keratinocytes. Collectively, the results indicated that TET2 knockdown may relieve inflammatory responses in the skin.

16.
Brief Bioinform ; 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32249290

RESUMO

Despite The Central Dogma states the destiny of gene as 'DNA makes RNA and RNA makes protein', the nucleic acids not only store and transmit genetic information but also, surprisingly, join in intracellular vital movement as a regulator of gene expression. Bioinformatics has contributed to knowledge for a series of emerging novel nucleic acids molecules. For typical cases, microRNA (miRNA), long noncoding RNA (lncRNA) and circular RNA (circRNA) exert crucial role in regulating vital biological processes, especially in malignant diseases. Due to extraordinarily heterogeneity among all malignancies, hepatocellular carcinoma (HCC) has emerged enormous limitation in diagnosis and therapy. Mechanistic, diagnostic and therapeutic nucleic acids for HCC emerging in past score years have been systematically reviewed. Particularly, we have organized recent advances on nucleic acids of HCC into three facets: (i) summarizing diverse nucleic acids and their modification (miRNA, lncRNA, circRNA, circulating tumor DNA and DNA methylation) acting as potential biomarkers in HCC diagnosis; (ii) concluding different patterns of three key noncoding RNAs (miRNA, lncRNA and circRNA) in gene regulation and (iii) outlining the progress of these novel nucleic acids for HCC diagnosis and therapy in clinical trials, and discuss their possibility for clinical applications. All in all, this review takes a detailed look at the advances of novel nucleic acids from potential of biomarkers and elaboration of mechanism to early clinical application in past 20 years.

17.
J Integr Neurosci ; 19(1): 39-49, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32259885

RESUMO

Depression is a common mental health disorder that can impair normal functions, cause distress, and adversely affect the quality of life. Cognitive impairment is considered one of the characteristics of major depression disorders-related dysfunction, and it has received attention in the treatment of major depressive disorders. To investigated the mechanisms underlying depression-induced cognitive disorders, we selected a rodent model of chronic unpredictable mild stress and used liquid chromatography/mass spectrometry-based metabolomics of sera. Behavioral tests, including the sucrose preference test and open field test, revealed that model rats developed depression-like symptoms in the sixth week of the chronic unpredictable mild stress period. Rats of the model group exhibited significant cognitive changes in the Morris water maze test in the tenth week of the period. Tau phosphorylation and decreased levels of postsynaptic density-95 and synaptophysin were observed in the rodent brains by the tenth week. These results suggest that rodents developed cognitive impairment in the tenth week of the period, while serum metabonomic showed that glycerophospholipid metabolism is the most relevant pathway to reveal the mechanism of depression-induced cognitive impairment. The disorders of lipid metabolism caused by the increased cholesterol efflux and reduced reuptake could be one of the mechanisms of depression-induced cognitive disorders. However, the relationship between cholesterol efflux in the brain and elevated serum cholesterol needs further research.

18.
J Urol ; : 101097JU0000000000001068, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32249664
19.
Hum Cell ; 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32314115

RESUMO

This study is to analyze the potential contribution of Syndecan 1 (SDC1) to cisplatin resistance in hepatic carcinoma. Cell proliferation and viability were determined by direct counting and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, respectively. The protein levels of SDC1, p-AKT, AKT and ß-actin were quantified by western blotting. The SDC1 transcript abundance was measured by real-time polymerase chain reaction. The relative expression of SDC1 in clinical liver tumor samples was analyzed with immunohistochemistry. SDC1 was up-regulated in cisplatin-resistant HepG2 cells (denoted as HepG2 CR hereafter). SDC1-knockdown re-sensitized HepG2 CR cells to cisplatin treatment. Ectopic over-expression of SDC1 conferred drug resistance to naïve HepG2 cells. PI3K/AKT pathway was over-activated in HepG2 CR cells, and simultaneous administration with PI3K inhibitor greatly surmounted the resistance. We also demonstrated that SDC1 was aberrantly up-regulated in clinical hepatocellular carcinoma samples. Our study highlighted the importance of SDC1-PI3K/AKT signaling in the cisplatin resistance in hepatocellular carcinoma.

20.
Biol Psychiatry ; 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32307038

RESUMO

BACKGROUND: Chronic pain patients often complain of their poor memory. The mechanisms underlying chronic pain-related memory impairment remain elusive, and there are few clinical therapeutic strategies available for this condition. METHODS: In a neuropathic pain model induced by chronic constrictive injury of the sciatic nerve in male mice, we used circuit-specific electrophysiological recording, combined with chemogenetic, molecular, and pharmacologic methods, to examine the circuit and molecular mechanisms underlying chronic pain-related memory impairment. RESULTS: Our current results show that chronic neuropathic pain impaired the acquisition of spatial memory and, meanwhile, reduced adult neurogenesis in the dentate gyrus. Experimentally reducing dentate gyrus neurogenesis mimicked this pain-induced effect on spatial memory formation in naïve mice. Furthermore, pain-associated impairments of both hippocampal neurogenesis and memory formation were rescued or mimicked by chemogenetic activation or deactivation, respectively, of the ventral tegmental area dopaminergic projection, through which ventral tegmental area-released brain-derived neurotrophic factor was required. Importantly, we found that chronic, but not acute, systematic administration of subanesthetic doses of ketamine, while without relieving pain, ameliorated chronic pain-related impairment of spatial memory formation, potentially by rescuing brain-derived neurotrophic factor-mediated dentate gyrus neurogenesis. CONCLUSIONS: These findings provide a novel, circuit-based mechanistic link between chronic pain and memory formation deficit, and potential new therapeutic options for chronic pain-related learning deficit and memory impairment.

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