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1.
Molecules ; 24(23)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31766469

RESUMO

Nowadays, the analysis of the multi-components in Chinese patent medicine prescriptions is being paid more attention. Therefore, in this study for the first time, a simple, rapid ultrahigh performance liquid chromatography-electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) method was established for simultaneous determination of 18 active compounds in a Chinese patent medicine of Hu Gan tablets (HGT) from different pharmaceutical factories in China. This task has met great emerging challenges from not only structural complexities and similarities but also co-occurrence of water-soluble and fat-soluble components in HGT. UPLC-ESI-MS/MS was put forward to solve the problems. It was operated in both positive and negative mode using multiple reaction monitoring (MRM). The mobile phase was 0.1% formic acid in water (A) -0.1% formic acid in acetonitrile (B) with linear gradient elution at a flow rate of 0.2 mL/min, run for a total of 12.0 min. The optimized method used provided short analysis time and good linearity (R2 > 0.99), and intra- and inter-day precision (relative standard deviation (RSD) < 4.00%) with good accuracy (94.89-110.03%) and recovery (70.00-126.09%). The results indicate the method could be practically used for quality guarantee of HGT and might also be useful for further studies.

2.
J Sleep Res ; : e12930, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31633865

RESUMO

Opioid-related deaths from respiratory depression are increasing but there is only limited information on the effect of morphine on breathing during sleep. This study aimed to detect and quantify opioid-induced cardiorespiratory pattern changes during sleep in obstructive sleep apnea (OSA) patients using novel automated methods and correlate these with conventional polysomnography (PSG) measures. Under a randomized double-blind placebo-controlled crossover design, 60 male OSA patients attended two one-night visits to the sleep laboratory, at least a week apart. Either a 40-mg controlled-release oral morphine dose or placebo was administered. Breathing during sleep was measured by standard in-laboratory PSG. We analysed the inter-breath interval (IBI) from the PSG flow channel to quantify breathing irregularity. Cardiopulmonary coupling (CPC) was analysed using the PSG electrocardiogram (ECG) channel. Following the consumption of morphine, the 60 OSA patients had fewer breaths (p = .0006), a longer inter-breath interval (p < .0001) and more irregular breathing with increased IBI coefficient of variation (CV) (p = .0015) compared to the placebo night. A higher CPC sleep quality index was found with morphine use. The change of key IBI and CPC parameters was significantly correlated with the change of key PSG sleep-disordered breathing parameters. In conclusion, 40 mg controlled-release morphine resulted in a longer breathing cycle and increased breathing irregularity but generally more stable sleep in OSA patients. The significant links between the IBI and CPC techniques and a range of PSG sleep-disordered breathing parameters may suggest a practical value as surrogate overnight cardiorespiratory measurements, because both respiratory flow and ECG can be detected by small portable devices.

3.
Plant Physiol ; 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31659126

RESUMO

Gibberellin (GA) is known to play an important role in low red/far-red (R:FR) light ratio-mediated hypocotyl and petiole elongation in Arabidopsis. However, the regulatory relationship between low R:FR and GAs remains unclear, especially in gymnosperms. To increase our understanding of the molecular basis of low R:FR-mediated shoot elongation in pines and to determine whether there is an association between low R:FR and GAs action, we explored the morphological and transcriptomic changes triggered by low R:FR, GAs, and paclobutrazol (PAC), a GAs biosynthesis inhibitor, in Pinus tabuliformis seedlings. Transcriptome profiles revealed that low R:FR conditions and GAs have a common set of transcriptional targets in P. tabuliformis. We provide evidence that the effect of low R:FR on shoot elongation in P. tabuliformis is at least partially modulated by GAs accumulation, which can be largely attenuated by PAC. GAs are also involved in the crosstalk between different phytohormones in the low R:FR response. A GA biosynthesis gene, encoding ent-kaurenoic acid oxidase (KAO), was strongly stimulated by low R:FR without being affected by GAs feedback regulation or the photoperiod. We show that GA signaling is required for low R:FR-induced shoot elongation in P. tabuliformis seedlings, and that there are different regulatory targets for low R:FR-mediated GA biosynthesis between conifers and angiosperms.

4.
Biomed Pharmacother ; 120: 109537, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31605951

RESUMO

BACKGROUND: Perivascular adipose tissue (PVAT) attenuates its anti-contractile effect through an endothelial-dependent mechanism that aggravates endothelial dysfunction in obesity. The present study was conducted to explore whether liraglutide could improve vascular dysfunction, including the anti-contractile effect of PVAT and endothelial function, by modulating PVAT-related signaling pathways in obesity. METHODS: C57BL/6 mice were fed a normal-chow diet or a high-fat diet (HFD) with or without liraglutide treatment. Vascular function of the thoracic aorta with or without PVAT were measured. Protein levels of components of the PKA-AMPK-PGC1α and antioxidant signaling pathway in PVAT were determined by western blotting. Brown adipose tissue-related gene in PVAT was measured by qRT-PCR. RESULTS: Metabolic profiles of HFD-fed mice were improved after treatment with liraglutide. Liraglutide improved PVAT-induced anti-contractile capability and PVAT-induced endothelial dysfunction in HFD-fed mice both in vivo and ex vivo. However, blocking PKA, or AMPK, but not cAMP, attenuated these beneficial effects of liraglutide. Treating HFD-fed mice with liraglutide activated the AMPK/eNOS pathway and induced browning-related gene expression. Moreover, liraglutide increased antioxidant capability. The protective effects were related to activation of a cAMP-independent PKA-AMPK pathway, as demonstrated by western blot and PCR. CONCLUSIONS: Liraglutide improved vascular dysfunction by modulating a cAMP-independent PKA-AMPK pathway in PVAT in HFD-induced obese mice. The findings provide a novel mechanism for the cardiovascular protection of liraglutide by modulating PVAT function in obesity.

5.
Medicine (Baltimore) ; 98(36): e16734, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31490363

RESUMO

The present study was conducted to evaluate the clinical outcomes of a modified all-inside arthroscopic repair technique via anterolateral and accessory anterolateral port for anterior talofibular ligament (ATFL) repair. A consecutive series of 32 patients (34 ankles) with chronic ankle instability were included and treated with the modified all-inside arthroscopic repair. The function was assessed using the American Orthopaedic Foot and Ankle Society (AOFAS), visual analog score (VAS) score system, the Sefton grading system, and the anterior drawer test and talar tilt test. A total of 29 cases (30 ankles) were followed up for a mean of 33.7 ±â€Š4.5 (range 30-44) months. Based on the Sefton grading system, 12 patients were regarded as excellent, 13 were good, 2 were fair, and 2 were poor. Twenty-five cases (86.2%) achieved satisfactory functional results. Ankle mobility returned to normal in 93% of patients. The AOFAS scores increased from 55.1 ±â€Š12.3 (range 25-69) preoperatively to 89.7 ±â€Š5.9 (range 74-100) (P < .001) at the last follow-up, while the VAS score decreased significantly (P < .001). There was no wound infection or nerve injury in all cases. In conclusion, based on high satisfaction rate in terms of ankle mobility and low complication rate, the modified all-inside arthroscopic repair of ATFL via anterolateral and accessory anterolateral port appears to be an effective treatment method for chronic ankle instability. Further studies are needed.


Assuntos
Articulação do Tornozelo/cirurgia , Artroscopia/métodos , Instabilidade Articular/cirurgia , Ligamentos Laterais do Tornozelo/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Amplitude de Movimento Articular , Contenções , Índices de Gravidade do Trauma , Adulto Jovem
6.
Invest Ophthalmol Vis Sci ; 60(12): 4052-4062, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31560770

RESUMO

Purpose: High myopia (HM) is defined as a refractive error worse than -6.00 diopter (D). This study aims to update the phenotypic and genotypic landscape of nonsyndromic HM and to establish a biological link between the phenotypic traits and genetic deficiencies. Methods: A cross-sectional study involving 731 participants varying in refractive error, axial length (AL), age, myopic retinopathy, and visual impairment. The phenotypic traits were analyzed by four ophthalmologists while mutational screening was performed in eight autosomal causative genes. Finally, we assessed the clinical relevance of identified mutations under the guidance of the American College of Medical Genetics and Genomics. Results: The relationship between refractive error and AL varied in four different age groups ranging from 3- to 85-years old. In adult groups older than 21 years, 1-mm increase in AL conferred 10.84% higher risk of pathologic retinopathy (Category ≥2) as well as 7.35% higher risk of low vision (best-corrected visual acuities <0.3) with P values < 0.001. The prevalence rates of pathologic retinopathy and low vision both showed a nonlinear positive correlation with age. Forty-five patients were confirmed to harbor pathogenic mutations, including 20 novel mutations. These mutations enriched the mutational pool of nonsyndromic HM to 1.5 times its previous size and enabled a statistically significant analysis of the genotype-phenotype correlation. Finally, SLC39A5, CCDC111, BSG, and P4HA2 were more relevant to eye elongation, while ZNF644, SCO2, and LEPREL1 appeared more relevant to refracting media. Conclusions: Our findings shed light on how multiple HM-related phenotypes are associated with each other and their link with gene variants.

7.
Synapse ; : e22134, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31562782

RESUMO

Synapse impairment is associated with post-traumatic stress disorder (PTSD), which is characterized by enhanced apoptosis in the hippocampus, amygdala, and other brain regions. However, there are no detailed studies on the relationship between apoptosis and synaptic connectivity in PTSD. In this review, we discuss results from various studies describing the synaptic changes observed in the PTSD brain. A decreased number of dendrites/spines or increased number of immature spines in the hippocampus, medial prefrontal cortex, and other brain regions has been reported. Studies on axon guidance, myelination, and the cytoskeleton suggest that PTSD may involve axon overgrowth and overbranching. Apoptosis affects synapse formation; low levels of caspase maintain the balance between growth cone attraction and repulsion and inhibit axon elongation. PTSD enhances neuronal apoptosis through caspase activation, which disrupts the balance between growth cone attraction and repulsion and alters growth cone trajectory, leading to axon mistargeting. Meanwhile, caspase activation induces dendritic pruning and dendrite degeneration. These events contribute to the formation of fewer and aberrant synapses, which is associated with enhanced apoptosis in PTSD.

8.
Neurobiol Dis ; 132: 104590, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31470106

RESUMO

While Brain-derived Neurotrophic Factor (BDNF) has long been implicated in treating neurological diseases, recombinant BDNF protein has failed in multiple clinical trials. In addition to its unstable and adhesive nature, BDNF can activate p75NTR, a receptor mediating cellular functions opposite to those of TrkB. We have now identified TrkB agonistic antibodies (TrkB-agoAbs) with several properties superior to BDNF: They exhibit blood half-life of days instead of hours, diffuse centimeters in neural tissues instead millimeters, and bind and activate TrkB, but not p75NTR. In addition, TrkB-agoAbs elicit much longer TrkB activation, reduced TrkB internalization and less intracellular degradation, compared with BDNF. More importantly, some of these TrkB-agoAbs bind TrkB epitopes distinct from that by BDNF, and work cooperatively with endogenous BDNF. Unlike BDNF, the TrkB-agoAbs exhibit a half-life of days/weeks and diffused readily in nerve tissues. We tested one of TrkB-agoAbs further and showed that it enhanced motoneuron survival in the spinal-root avulsion model for motoneuron degeneration in vivo. Thus, TrkB-agoAbs are promising drug candidates for the treatment of neural injury.

9.
Neuropharmacology ; 162: 107736, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31398381

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder, characterized by social interaction impairment, stereotypical/repetitive behaviors and emotional deregulation. The endocannabinoid (eCB) system plays a crucial role in modulating the behavioral traits that are typically core symptoms of ASD. The major molecular mechanisms underlying eCB-dependent long-term depression (eCB-LTD) are mediated by group 1 metabotropic glutamate receptor (mGluR)-induced removal of postsynaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs). Recently, modulation of anandamide (AEA), one of the main endocannabinoids in the brain, has been reported to alter social behaviors in genetic models of ASD. On this basis, we investigated the effects of treatment and the synaptic mechanism underlying AEA-mediated signaling in prenatal exposure to valproic acid (VPA) in rats. We found that the social deficits, repetitive behaviors and abnormal emotion-related behaviors in VPA-exposed offspring were improved after treatment with an inhibitor of AEA degrading enzyme, URB597. Using an integrative approach combing electrophysiological and cellular mechanisms, the results showed that the impaired eCB-LTD, abnormal mGluR-mediated LTD (mGluR-LTD) and decreased removal of AMPAR subunits GluA1 and GluA2 were reversed by URB597 in the prefrontal cortex (PFC) of VPA-exposed offspring. Taken together, these results provide the first evidence that rescue of the ASD-like phenotype by URB597 is mediated by enhancing the mechanism of removal of AMPAR subunits GluA1/2 underlying AEA signaling in the PFC in a VPA-induced model of ASD.

10.
Nanoscale ; 11(27): 13078-13088, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31265049

RESUMO

Although photodynamic therapy (PDT), which uses a photosensitizer (PS) to generate toxic reactive oxygen species (ROS) upon laser irradiation to kill cancer cells, has been widely applied, the relatively high laser intensity required causes photodamage to healthy neighboring cells and limits its success. Furthermore, glutathione (GSH, an antioxidant) is overexpressed in cancer cells, which can scavenge the generated ROS, thus lowering PDT efficacy. Herein, ultralow-intensity near-infrared (NIR) light-triggered PDT was developed and enhanced through combined GSH-depletion chemotherapy (Chemo) based on exo- and endogenous synergistic effects. Highly emissive upconversion nanoparticles (UCNPs) were prepared and coated with a solid silica shell, which was used to encapsulate the PS rose bengal and bond the drug camptothecin with a disulfide-bond linker. The combination of highly emissive UCNPs and a matchable PS with an optimized loading dosage enabled ROS to be generated for PDT even upon 808 nm laser irradiation with ultralow intensity (0.30 W cm-2). According to the American National Standard, this laser intensity is below the maximum permissible exposure of skin (MPE, 0.33 W cm-2). Once the prepared nanoparticles endocytosed and encountered intracellular GSH, the disulfide-bond linker was cleaved by GSH, leading to drug release and GSH depletion. PDT was therefore simultaneously enhanced through the exogenous synergic effect of Chemo (namely, the "1 + 1 > 2" therapeutic effect) and the endogenous synergic effect as a result of GSH depletion. It was proven both in vitro and in vivo that this novel dual-synergistic Chemo/PDT system exhibits remarkable therapeutic efficacy with minimal photodamage to healthy neighboring cells.

11.
Brain Stimul ; 12(6): 1410-1420, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31324604

RESUMO

BACKGROUND: Social deficit is a core symptom in autism spectrum disorder (ASD). Although deep brain stimulation (DBS) has been proposed as a potential treatment for ASD, an ideal target nucleus is yet to be identified. DBS at the central thalamic nucleus (CTN) is known to alter corticostriatal and limbic circuits, and subsequently increase the exploratory motor behaviors, cognitive performance, and skill learning in neuropsychiatric and neurodegenerative disorders. OBJECTIVE: We first investigated the ability of CTN-DBS to selectively engage distinct brain circuits and compared the spatial distribution of evoked network activity and modulation. Second, we investigated whether CTN-DBS intervention improves social interaction in a valproic acid-exposed ASD rat offspring model. METHODS: Brain regions activated through CTN-DBS by using a magnetic resonance (MR)-compatible neural probe, which is capable of inducing site-selective microstimulations during functional MRI (fMRI), were investigated. We then performed functional connectivity MRI, the three-chamber social interaction test, and Western blotting analyses to evaluate the therapeutic efficacy of CTN-DBS in an ASD rat offspring model. RESULTS: The DBS-evoked fMRI results indicated that the activated brain regions were mainly located in cortical areas, limbic-related areas, and the dorsal striatum. We observed restoration of brain functional connectivity (FC) in corticostriatal and corticolimbic circuits after CTN-DBS, accompanied with increased social interaction and decreased social avoidance in the three-chamber social interaction test. The dopamine D2 receptor decreased significantly after CTN-DBS treatment, suggesting changes in synaptic plasticity and alterations in the brain circuits. CONCLUSIONS: Applying CTN-DBS to ASD rat offspring increased FC and altered the synaptic plasticity in the corticolimbic and the corticostriatal circuits. This suggests that CTN-DBS could be an effective treatment for improving the social behaviors of individuals with ASD.

12.
Chin Med J (Engl) ; 132(15): 1796-1801, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31343434

RESUMO

BACKGROUND: Recent genome-wide association studies have identified an important role of T-cell receptor α (TRA) gene in the development of narcolepsy type 1. However, the role of TRA haplotype polymorphisms in the symptomatic diversity of narcolepsy remains unclear. This study aimed to investigate whether TRA polymorphisms can influence the symptomatic diversity of narcolepsy. METHODS: Totally, 903 patients with narcolepsy type 1 were included in the study. Patients were divided into different groups according to their symptoms. First, 13 genotyped single nucleotide polymorphisms in the TRA were assessed for their association with symptoms of narcolepsy. We used the Chi-square test to determine differences in genotype frequencies in patients with narcolepsy. Further, we identified the haplotypes and variations of the TRA and tested their association with the symptoms of narcolepsy using a logistic regression model. RESULTS: According to the results of the logistic regression, TRA haplotypes TG and CT were significantly associated with auditory hallucination, with odds ratios of 1.235 (95% confidence interval [CI], 1.012-1.507) and 1.236 (95% CI, 1.012-1.511), respectively (P < 0.05). CONCLUSIONS: The patterns of haplotype in TRA (haplotypes TG and CT) are associated with hypnagogic auditory hallucination in patients with narcolepsy type 1. However, further studies are needed to confirm our results and explore the underlying mechanisms.

13.
Se Pu ; 37(7): 712-722, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31271010

RESUMO

A liquid chromatography-tandem mass spectrometry method for the identification of marker peptides of aquatic product allergens and quantitative detection of multiple allergens in meat products and seasonings was developed. The samples were prepared by protein extraction, protein purification, and trypsin hydrolysis. The proteins and peptides were identified using ProteinPilot by the data analysis of the ion spectrum of polypeptide fragments using ultra-performance liquid chromatography-quadrupole/electrostatic orbitrap high-resolution mass spectrometry (UPLC-Q/Exactive-HRMS). The identification of 30 species-specific marker peptides in Penaeus vannamei, Eriocheir, Scylla serrata, Thunnus thynnus, and Atlantic salmon by comparison of the basic local alignment search tool (BLAST) with the UniProt database was achieved. The verification and multiple reaction monitoring (MRM) quantitative studies of these marker peptides were performed using a triple quadrupole mass spectrometry (UPLC-QqQ-MS) system. The proposed method showed a good linear relationship in the range of 5-250 mg/kg. The limits of quantitation and observed recoveries were in the range of 2-3.5 mg/kg and 88.7%-110.2%, respectively. This method presents various advantages such as good repeatability and high throughput, suitability for rapid screening, and quantitative analysis of seven aquatic allergens in meat products and seasonings.


Assuntos
Alérgenos/análise , Proteínas de Peixes/análise , Contaminação de Alimentos/análise , Produtos da Carne/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Espectrometria de Massas em Tandem
14.
Sci Data ; 6(1): 132, 2019 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-31341172

RESUMO

Collichthys lucidus (C. lucidus) is a commercially important marine fish species distributed in coastal regions of East Asia with the X1X1X2X2/X1X2Y multiple sex chromosome system. The karyotype for female C. lucidus is 2n = 48, while 2n = 47 for male ones. Therefore, C. lucidus is also an excellent model to investigate teleost sex-determination and sex chromosome evolution. We reported the first chromosome genome assembly of C. lucidus using Illumina short-read, PacBio long-read sequencing and Hi-C technology. An 877 Mb genome was obtained with a contig and scaffold N50 of 1.1 Mb and 35.9 Mb, respectively. More than 97% BUSCOs genes were identified in the C. lucidus genome and 28,602 genes were annotated. We identified potential sex-determination genes along chromosomes and found that the chromosome 1 might be involved in the formation of Y specific metacentric chromosome. The first C. lucidus chromosome-level reference genome lays a solid foundation for the following population genetics study, functional gene mapping of important economic traits, sex-determination and sex chromosome evolution studies for Sciaenidae and teleosts.

15.
Biomater Sci ; 7(9): 3683-3692, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31361291

RESUMO

Synergistic cancer starvation/ROS-mediated/chemo-therapy is developed through a cascade reaction with enzyme glucose oxidase (GOX) modified on the surface of an Fe-based metal organic framework (MOF(Fe)) and drug camptothecin (CPT) loaded into the cavities of MOF(Fe). Once internalized by tumor cells, GOX catalyzes endogenous glucose into hydrogen peroxide (H2O2) and gluconic acid (H+) enabling starvation therapy through choking off energy (glucose) supply. Meanwhile, the acidic micro-environment of tumor enhanced by the generated H+ degrades the MOF(Fe) simultaneously releasing CPT for chemotherapy and Fe3+, catalyzing H2O2 into one of the strongest reactive oxygen species (ROS) ˙OH enabling ROS-mediated therapy. Both in vitro and in vivo results show remarkable tri-modal synergistic anticancer effects. This work may shed some light on the development of novel multi-modal cancer therapies without any external intervention.

16.
Nat Rev Neurol ; 15(9): 519-539, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31324898

RESUMO

Narcolepsy is a rare brain disorder that reflects a selective loss or dysfunction of orexin (also known as hypocretin) neurons of the lateral hypothalamus. Narcolepsy type 1 (NT1) is characterized by excessive daytime sleepiness and cataplexy, accompanied by sleep-wake symptoms, such as hallucinations, sleep paralysis and disturbed sleep. Diagnosis is based on these clinical features and supported by biomarkers: evidence of rapid eye movement sleep periods soon after sleep onset; cerebrospinal fluid orexin deficiency; and positivity for HLA-DQB1*06:02. Symptomatic treatment with stimulant and anticataplectic drugs is usually efficacious. This Review focuses on our current understanding of how genetic, environmental and immune-related factors contribute to a prominent (but not isolated) orexin signalling deficiency in patients with NT1. Data supporting the view of NT1 as a hypothalamic disorder affecting not only sleep-wake but also motor, psychiatric, emotional, cognitive, metabolic and autonomic functions are presented, along with uncertainties concerning the 'narcoleptic borderland', including narcolepsy type 2 (NT2). The limitations of current diagnostic criteria for narcolepsy are discussed, and a possible new classification system incorporating the borderland conditions is presented. Finally, advances and obstacles in the symptomatic and causal treatment of narcolepsy are reviewed.

18.
Aquat Toxicol ; 214: 105254, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31357109

RESUMO

Intracellular copper/zinc superoxide dismutase (icCuZnSOD) is a member of superoxide dismutase family that is capable of catalyzing the superoxide radicals into either hydrogen peroxide (H2O2) or ordinary molecular oxygen (O2). Unlike mammals, the study of icCuZnSOD in aquatic animals is still in the infancy stage. Here, we identified the cDNA of na-iccuznsod from yellow drum (Nibea albiflora, Richardson 1846) and obtained its fusion protein for the first time. The mRNA expressions of na-iccuznsod were investigated in different tissues, and the dominant distribution was found in head-kidney, followed by brain, liver, heart, and gill. The effects of ammonia-N/nitrite-N on the mRNA expressions of na-iccuznsod were investigated. Na-iccuznsod transcription levels showed a general tendency of an initial up-regulation followed by a down-regulation in liver, gill, and head-kidney when yellow drum were exposed to ammonia-N/nitrite-N at the lethal concentration 50 at 96 h post-treatment, suggesting the important role of Na-icCuZnSOD in eliminating reactive oxygen species (ROS) induced by ammonia-N/nitrite-N. In addition, the characteristics of Na-icCuZnSOD protein and its comparative analysis with Na-ecCuZnSOD were investigated. Na-icCuZnSOD protein showed high enzyme stabilities over a wide range of temperature (10 to 60 °C) and pH (4.9 to 11.0), indicating its broad in vitro applications in many industries. Furthermore, the comparative analysis of Na-icCuZnSOD and Na-ecCuZnSOD gives a new perspective for the study of their structure-function relationship. Collectively, the present study will advance our understanding of the toxicity of ammonia-N/nitrite-N on yellow drum through testing the mRNA expression of iccuznsod gene, and broaden our knowledge of the protein characteristics of icCuZnSOD from fish.


Assuntos
Amônia/toxicidade , Cobre/metabolismo , Regulação Enzimológica da Expressão Gênica , Nitritos/toxicidade , Perciformes/genética , Estresse Fisiológico/genética , Superóxido Dismutase/genética , Zinco/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/genética , Estabilidade Enzimática/efeitos dos fármacos , Escherichia coli/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Filogenia , Estrutura Terciária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Superóxido Dismutase/química , Superóxido Dismutase/metabolismo , Temperatura Ambiente , Fatores de Tempo , Poluentes Químicos da Água/toxicidade
19.
Sensors (Basel) ; 19(11)2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31159161

RESUMO

Timber structures have been widely used due to their low-cost and environmental-friendly properties. It is essential to monitor connection damage to ensure the stability and safety of entire timber structures since timber connection damage may induce catastrophic incidents if not detected in a timely manner. However, the current investigations on timber connections focus on mechanical properties and failure modes, and the damage detection of timber connection receives rare attention. Therefore, in this paper, we investigate the damage detection of four common timber connections (i.e., the screw connection, the bolt connection, the decussation connection, and the tooth plate connection) by using the active sensing method. The active sensing method was implemented by using a pair of lead zirconate titanate (PZT) transducers: one PZT patch is used as an actuator to generate stress waves, and the other works as a sensor to detect stress waves after propagating across the timber connection. Based on the wavelet packet energy analysis, the signal energy levels of received stress waves under different damage extent are quantified. Finally, by comparing the signal energy between the intact status and the damage status of the timber connection, we find that the energy attenuates with increasing severity of the connection damage. The experimental results demonstrate that the active sensing method can realize real-time monitoring of timber connection damage, which can guide further investigations.

20.
BMC Mol Cell Biol ; 20(1): 15, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31216990

RESUMO

BACKGROUND: To investigate the effects of serum amyloid A1 (SAA1) on lipopolysaccharide (LPS) -induced inflammation in vascular smooth muscle cells (VSMCs). SAA1 expression was detected in LPS induced VSMCs at different concentrations for different time by using Western blotting. After pre-incubation with recombinant SAA1 protein, VSMCs were treated with 1 µg/ml LPS for 24 h. The VSMCs were then divided into Control, SAA1 siRNA, Nox4 siRNA, LPS, LPS + SAA1 siRNA, LPS + Nox4 siRNA and LPS + SAA1 siRNA + Nox4 groups. MTT was performed to observe the toxicity of VSMCs. Lucigenin-enhanced chemiluminescence method was used to detect superoxide anion (O2-) production and NADPH oxidase activity. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine expressions of inflammatory factors. Western blotting was used to determine expressions of NOX-4 and p38MAPK/NF-κB pathway related proteins. RESULTS: LPS promoted SAA1 protein expression in a concentration-/time-dependent manner. Recombinant SAA1 protein could increase NOX4/ROS production and promote the release of inflammatory factors (IL-1ß, IL-6, IL-8, IL-17, TNF-α and MCP-1) in LPS (1 µg/ml) - induced VSMCs. Besides, both SAA1 siRNA and NOX-4 siRNA could not only enhance the O2- production and NADPH oxidase activity, but also up-regulate the protein expression of NOX4, the release of inflammatory factors, and the levels of p-p38 and p-NF-κB p65 in LPS-induced VSMCs. However, no significant differences in each index were observed between LPS group and LPS + SAA1 siRNA + Nox4 group. CONCLUSION: SAA1-mediated NOX4/ROS pathway could activate p38MAPK/NF-κB pathway, thereby contributing to the release of inflammatory factors in LPS-induced VSMCs.

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