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1.
Free Radic Res ; : 1-63, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33059489

RESUMO

Reactive oxygen species (ROS) play a crucial role in many physiological processes. However, ROS overproduction leads to oxidative stress, which plays a critical role in cell injury/death and the pathogenesis of many diseases. Members of NADPH oxidase (NOX) family, most of which are comprised of membrane and cytosolic components, are known to be the major non-mitochondrial sources of ROS in many cells. NOX2 is a widely-expressed and well-studied NOX family member, which is activated upon assembly of its membrane subunits gp91phox and p22phox with its cytosolic subunits p40phox, p47phox, p67phox, and Rac, facilitating ROS production. NOX2 activation is also enhanced by GTP and inhibited by GDP. However, there remains a lack of a mechanistic, quantitative, and integrated understanding of the kinetics and regulation of the assembly of these subunits and their relative contributions towards NOX2 activation and ROS production. Towards this end, we have developed a mechanistic computational model, which incorporates a generalized random rapid equilibrium binding mechanism for NOX2 assembly and activation as well as regulations by GTP (activation), GDP (inhibition), and individual subunits enhancing the binding of other subunits (mutual binding enhancement). The resulting model replicates diverse published kinetic data, including subunit concentration-dependent NOX2 activation and ROS production, under different assay conditions, with appropriate estimates of the unknown model parameters. The model provides a mechanistic, quantitative, and integrated framework for investigating the critical roles of NOX2 subunits in NOX2 assembly and activation facilitating ROS production in a variety of physiological and pathophysiological conditions. However, there is also a need for better quantitative kinetic data based on current understanding of NOX2 assembly and activation in order to test and further develop this model.

2.
Prog Brain Res ; 255: 99-121, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33008517

RESUMO

Migraine is a common and highly disabling headache disorder associated with a substantial socioeconomic burden. Migraine treatments can be categorized as preventive treatment, aimed at reducing the frequency and severity of migraine attacks, and acute therapy, intended to abort attacks. Traditionally, acute treatment can be classified as specific (ergot derivatives and triptans) or nonspecific (analgesics and nonsteroidal anti-inflammatory drugs). Triptans, a class of 5-HT1B/1D receptor agonists with some affinity for the 5-HT1F receptor subtype, have been proven to be efficacious for acute treatment of moderate to severe migraine and have been deemed the gold standard. The availability of triptans in non-oral formulations, such as subcutaneous (SC) and intranasal forms, can be beneficial for patients who suffer from prominent nausea or vomiting, have a suboptimal response to oral agents, and/or seek a more rapid onset of treatment effects. However, triptans are contraindicated in patients with preexisting cardiovascular and/or cerebrovascular diseases due to their 5-HT1B-mediated vasoconstrictive action. For this reason, studies have focused on the development of ditans, a group of antimigraine drugs targeting 5-HT1D and 5-HT1F receptors. Unfortunately, 5-HT1D receptor agonists have been shown to be ineffective in the acute treatment of migraine. Several ditans targeting the 5-HT1F receptor have been developed and have shown no vasoconstrictive effect in preclinical studies, but only two of them, lasmiditan and LY334370, have been tested in clinical trials for migraine, and only lasmiditan has reached to Phase III clinical trials. These Phase III trials have demonstrated the efficacy and safety of lasmiditan, a selective 5-HT1F receptor agonist, in acute migraine treatment. Lasmiditan might offer an alternative migraine therapy without cardiovascular risks. This review will summarize the development of agents targeting the 5-HT1B/1D and 5-HT1F receptors and the clinical evidence supporting the use of these agents for acute migraine treatment.

3.
Chem Commun (Camb) ; 2020 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-33099589

RESUMO

Industrially, large-scale NH3 production is achieved by the Haber-Bosch process, which operates under harsh reaction conditions with abundant energy consumption and CO2 emission. Electrochemical N2 reduction is an eco-friendly and energy-saving method for artificial N2 to NH3 fixation under ambient reaction conditions. Herein, we demonstrate that ZrS2 nanofibers with a sulfur vacancy (ZrS2 NF-Vs) behave as an efficient electrocatalyst for ambient N2 reduction to NH3 with excellent selectivity. In 0.1 M HCl, this ZrS2 NF-Vs catalyst attains a large NH3 yield of 30.72 µg h-1 mgcat.-1 and a high faradaic efficiency of 10.33% at -0.35 V and -0.30 V vs. reversible hydrogen electrode, respectively. It also shows high electrochemical and structural stability. The density functional theory calculations reveal that the introduction of Vs facilitates the adsorption and activation of N2 molecules.

4.
J Colloid Interface Sci ; 584: 403-410, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33091865

RESUMO

HYPOTHESIS: Freezing morphologies of impacting water droplets depend on the interaction between droplet spreading and solidification. The existing studies showed that the shape of frozen droplets mostly is of spherical cap with a singular tip, because of much shorter timescale of the droplet spreading than that of the solidification. Here, we create the experimental conditions of extended droplet spreading and greatly enhanced heat transfer for fast solidification, thereby allowing to study such droplet freezing process under the strong coupling of the droplet spreading and solidification. EXPERIMENTS: We design experiments that a room-temperature water droplet impacts on a subcooled superhydrophilic surface in an enclosure chamber filled with nitrogen gas. We thoroughly investigate the freezing processes of impacting droplets under the effects of impact velocity and substrate temperature. Both the droplet impact dynamics and solidification are studied with a high-speed camera. FINDINGS: We observed five different freezing morphologies which depend on the droplet impact velocity and substrate temperature. We found that the formation of diverse morphologies results from the competitive timescales related to droplet solidification and impact hydrodynamics. We also develop a phase diagram based on scaling analysis and show how freezing morphologies are controlled by droplet impact and freezing related timescales.

5.
Medicine (Baltimore) ; 99(41): e22684, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33031338

RESUMO

Previous studies have indicated that the prevalence of gestational diabetes mellitus (GDM) was related to the season. However, there was no relevant information in Asia. The aim of this study was to determine whether there was seasonality of GDM and maternal blood glucose level in Taiwanese women.A total of 6396 pregnancies were enrolled between 2012 and 2014 in this retrospective study. A 2-step approach according to the Carpenter-Coustan criteria was used for GDM diagnosis. A generalized linear mixed model was used to estimate the effect of season on GDM diagnosis by adjusting for age, prepregnancy body mass index, parity, history of GDM, fetal sex, and the rate of weight gain.During the study period, 418 (6.5%) pregnancies were diagnosed as GDM. The model demonstrated an increased prevalence of GDM in spring and summer (odds ratio: 1.59, 95% confidence interval: 1.13-2.24; odds ratio: 1.59, 95% confidence interval: 1.14-2.23, respectively) compared to winter. For the glucose level variation, the model demonstrated an increase of 2.56 mg/dL glucose in the 50-g glucose challenge test in summer compared to winter. In glucose challenge test-positive pregnancies, the season also had an effect on the results of the 100-g 1-h, 2-h, and 3-h oral glucose tolerance tests, but no effect on the 100-g fasting oral glucose tolerance tests.GDM prevalence in Taiwan presents seasonal variation, with the highest risk during spring and summer due to post-glucose load level variations. These findings could serve as reference data for countries in Southeast Asia or areas with a similar climate.


Assuntos
Glicemia , Diabetes Gestacional/epidemiologia , Estações do Ano , Adulto , Diabetes Gestacional/sangue , Feminino , Humanos , Gravidez , Prevalência , Estudos Retrospectivos , Taiwan/epidemiologia , Adulto Jovem
6.
Int J Immunopathol Pharmacol ; 34: 2058738420962902, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33045857

RESUMO

Atopic dermatitis (AD) is a skin disease characterized by chronic inflammatory condition that shows hallmark presentations in terms of sleep disturbances, pruritus, and psychological stress, and an association with increased attention deficit/hyperactivity disorder (ADHD) risk. A number of studies have suggested for the co-occurrence of the two diseased conditions. In terms of global prevalence, AD and ADHD almost exhibit a parallel increment according to epidemiological data. In addition, recent reports indicate AD to show a temporal association with later onset of ADHD. Although several studies suggest for the potential link between AD and ADHD, currently there is no definitive answer to this regard. Furthermore, epidemiological evidence of co-occurrence does not ascertain a pathophysiological link between the two conditions. The pathophysiological basis behind the association of AD and ADHD also remain poorly elucidated. The objective of this review is to present an extensive account of AD and associated comorbidities with a special attention toward ADHD as well as to elaborate on the mechanisms underlying their association. The review can provide healthcare providers with the recent updates on AD-ADHD association and help them while dealing with such patients. In general, AD and ADHD show a positive association in majority of the cross-sectional studies. However, large longitudinal studies are required to draw any conclusion on the temporal nature of such association.

7.
Sci Total Environ ; 755(Pt 2): 142617, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33045602

RESUMO

Although benzothiazole and its derivatives (BTHs) are considered emerging contaminants in diverse environments and organisms, little information is available about their contamination profiles and health impact in ambient particles. In this study, an optimized method of ultrasound-assisted extraction coupled with the selected reaction monitoring (SRM) mode of GC-EI-MS/MS was applied to characterize and analyze PM2.5-bound BTHs from three cities of China (Guangzhou, Shanghai, and Taiyuan) during the winter of 2018. The total BTH concentration (ΣBTHs) in PM2.5 samples from the three cities decreased in the order of Guangzhou > Shanghai > Taiyuan, independently of the PM2.5 concentration. Despite the large variation in concentration of ΣBTHs in PM2.5, 2-hydroxybenzothiazole (OTH) was always the predominant compound among the PM2.5-bound BTHs and accounted for 50-80% of total BTHs in the three regions. Results from human exposure assessment and toxicity screening indicated that the outdoor exposure risk of PM2.5-bound BTHs in toddlers was much higher than in adults, especially for OTH. The developmental and reproduction toxicity of OTH was further explored in vivo and in vitro. Exposure of mouse embryonic stem cells (mESCs) to OTH for 48 h significantly increased the intracellular reactive oxygen species (ROS) and induced DNA damage and apoptosis via the functionally activating p53 expression. In addition, the growth and development of zebrafish embryos were found to be severely affected after OTH treatment. An overall metabolomics study was conducted on the exposed zebrafish larvae. The results indicated that exposure to OTH inhibited the phenylalanine hydroxylation reaction, which further increased the accumulation of toxic phenylpyruvate and acetylphenylalanine in zebrafish. These findings provide important insights into the contamination profiles of PM2.5-bound BTHs and emphasize the health risk of OTH.

8.
J Therm Biol ; 93: 102731, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33077142

RESUMO

Understanding the factors that may affect behavioural thermoregulation of endangered reptiles is important for their conservation because thermoregulation determines body temperatures and in turn physiological functions of these ectotherms. Here we measured seasonal variation in operative environmental temperature (Te), body temperature (Tb), and microhabitat use of endangered crocodile lizards (Shinisaurus crocodilurus) from a captive population, within open and shaded enclosures, to understand how they respond to thermally challenging environments. Te was higher in open enclosures than in shaded enclosures. The Tb of lizards differed between the open and shaded enclosures in summer and autumn, but not in spring. In summer, crocodile lizards stayed in the water to avoid overheating, whereas in autumn, crocodile lizards perched on branches seeking optimal thermal environments. Crocodile lizards showed higher thermoregulatory effectiveness in open enclosures (with low thermal quality) than in shaded enclosures. Our study suggests that the crocodile lizard is capable of behavioural thermoregulation via microhabitat selection, although overall, it is not an effective thermoregulator. Therefore, maintaining diverse thermal environments in natural habitats for behavioural thermoregulation is an essential measure to conserve this endangered species both in the field and captivity.

9.
Commun Biol ; 3(1): 561, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037315

RESUMO

Chemical molecules specifically secreted into the blood and targeted tissues by intestinal microbiota can effectively affect the associated functions of the intestine especially immunity, representing a new strategy for immune-related diseases. However, proper ways of regulating the secretion metabolism of specific strains still remain to be established. In this article, an upconversion optogenetic micro-nanosystem was constructed to effectively regulate the specific secretion of engineered bacteria. The system included two major modules: (i) Modification of secretory light-responsive engineered bacteria. (ii) Optical sensing mediated by upconversion optogenetic micro-nanosystem. This system could regulate the efficient secretion of immune factors by engineered bacteria through optical manipulation. Inflammatory bowel disease and subcutaneously transplanted tumors were selected to verify the effectiveness of the system. Our results showed that the endogenous factor TGF-ß1 could be controllably secreted to suppress the intestinal inflammatory response. Additionally, regulatory secretion of IFN-γ was promoted to slow the progression of B16F10 tumor.

10.
Clin Pharmacol Ther ; 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978779

RESUMO

This study explored heterogeneous treatment effects (HTEs) of the real-world use of dipeptidyl peptidase-4 inhibitors (DPP-4is) vs. sulfonylureas (SUs) on cardiovascular diseases (CVDs) and mortality in patients with type 2 diabetes. Utilizing Taiwan's National Health Insurance Research Database, 19,853 propensity score-matched pairs of DPP-4i and SU stable users were identified. Classification and regression tree analyses and Cox models were applied to explore HTEs, according to various patient characteristics, on the composite CVDs, three-point major adverse cardiovascular event (MACE), and all-cause mortality. The absolute risk difference (ARD), hazard ratio (HR), and 95% confidence interval (CI) were estimated for comparing treatment effects. CVD history, ischemic stroke, or transient ischemic attack (IS/TIA) history, and age at treatment initiation were significant treatment effect modifiers. Patients with prior IS/TIA but without any other prior CVDs benefited most in reduced risks of composite CVDs from using DPP-4i vs. SU (ARD -4.31%, 95% CI -7.48% to -1.14%, HR 0.81, 95% CI 0.69 ~ 0.95), followed by those without prior IS/TIA and CVDs and initiated with DPP-4i at age < 69.3 years (ARD -0.90%, 95% CI -1.47% to -0.32%, HR 0.86, 95% CI 0.77 ~ 0.97). Patients with prior IS/TIA benefited most in reduced risks of three-point MACE from using DPP-4i vs. SU (ARD -4.22%, 95% CV -6.66% to -1.78%, HR 0.80, 95% CI 0.69 ~ 0.93), followed by those without prior IS/TIA and initiated with DPP-4i at age < 69.3 years (ARD -0.68%, 95% CI -1.08% to -0.29%, HR 0.81, 95% CI 0.70 ~ 0.93). Consideration of CVD and IS/TIA histories and age could facilitate individualized diabetes management of using DPP-4i vs. SU. Future studies are warranted given the hypothesis-generating nature in this exploratory research.

11.
Med Sci Monit ; 26: e926443, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32893845

RESUMO

BACKGROUND Curcumin is a component of Curcuma longa with various biological activities. The present study aimed to investigate curcumin's inhibitory effects on epithelial-mesenchymal transition (EMT) in colorectal cancer (CRC) cells and possible mechanisms of action underlying these effects. MATERIAL AND METHODS Human SW480 CRC cells were incubated with curcumin at 0.1, 0.2, 0.4, 0.8, or 1.6 µmol/L. The 3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay was utilized to evaluate cell viabilities. The DNA methylation levels of the cdx2 promoter were assessed by bisulfite sequencing polymerase chain reaction (BSP). Real-time quantitative PCR was used to measure the mRNA expression levels. Protein expression levels were evaluated with western blotting. Immunofluorescence staining was used to evaluate the nuclear translocation of ß-catenin. RESULTS Curcumin concentrations of 0.1, 0.2, and 0.4 µmol/L showed no significant association with the viability of SW480 cells, which were chosen for subsequent experiments. Curcumin incubation significantly downregulated expression levels of DNA methyltransferase1 (DNMT1), DNMT3a, and the methylation levels of the cdx2 promoter in a concentration-dependent manner. The expression levels of N-cadherin, Vimentin, Wnt3a, Snail1, and Twist, as well as the nuclear translocation levels of ß-catenin, were reduced in a curcumin concentration-dependent manner. The expression levels of E-cadherin were increased in a curcumin concentration-dependent manner. CONCLUSIONS Curcumin negatively regulated transcription factors promoting EMT in CRC cells by decreasing cdx2 promoter DNA methylation and consequently suppressing the CDX2/Wnt3a/ß-catenin signaling pathway.

12.
Gene ; 766: 145153, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32950633

RESUMO

AIM: Acute lung injury (ALI) is the mild form of acute respiratory distress syndrome (ARDS) which is a common lung disease with a high incidence and mortality rate. Recent studies manifested that some circular RNAs were associated with ALI. In this study, we aimed to uncover the effect of circular RNA circ_0054633 on ALI initiation and progression and proposed a new mechanism related to ALI. METHODS: The lipopolysaccharides (LPS)-induced acute lung injury model were build both in vivo of rat and in vitro of primary murine pulmonary microvascular endothelial cells (MPVECs). Hematoxylin and eosin (H&E) was employed to observe the tissue morphology and estimate the degree of lung damage. We used real-time quantitative polymerase chain reaction (RT-qPCR) to measure the expression level of circ_0054633. The expression levels of inflammatory cytokines IL-17A and tumor necrosis factor-α (TNF-α) were detected by ELISA. The effects of circ_0054633 on MPVECs proliferation and apoptosis were detected with the help of CCK-8 and apoptosis assay, separately. The expression level of NF-κB p65 protein was measured by Western blot. RESULTS: circ_0054633, IL-17A, TNF-α and NF-κB p65 were all overexpressed in LPS-treated rat and MPVECs, and LPS enhanced the proliferation and apoptosis of MPVECs. While circ_0054633 silencing reversed the above promotion effects of LPS on IL-17A, TNF-α expression and MPVECs proliferation and apoptosis. CONCLUSIONS: Quietness of circ_0054633 alleviated LPS-induced ALI via NF-κB signaling pathway, implicating circ_0054633 may be a potential biomarker for diagnose and therapy of ALI.

13.
J Comp Neurol ; 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32965038

RESUMO

Chronic stress can induce cognitive impairment, and synapse number was significantly decreased in the hippocampus of rats suffering from chronic stress. Lingo-1 is a potent negative regulator of axonal outgrowth and synaptic plasticity. In the current study, the effects of anti-Lingo-1 antibody on the spatial learning and memory abilities and hippocampal synapses of stressed rats were investigated. After 4 weeks of stress exposure, the model group was randomly divided into a chronic stress group and an anti-Lingo-1 group. Then, the anti-Lingo-1 group rats were treated with anti-Lingo-1 antibody (8 mg/kg) for 3 weeks. The effects of anti-Lingo-1 antibody on the spatial learning and memory abilities were investigated with the Morris water maze test. Immunohistological staining and an unbiased stereological method were used to estimate the total number of dendritic spine synapses in the hippocampus. At the behavioral level, after 3 weeks of treatment, the anti-Lingo-1 group rats displayed significantly more platform location crossings in the Morris water maze test than the chronic stress group rats. Anti-Lingo-1 significantly prevented the declines in dendritic spine synapses and postsynaptic density protein-95 (PSD-95) expression in the dentate gyrus and the CA1 and CA3 regions of the hippocampus. The present results indicated that anti-Lingo-1 antibody may be a safe and effective drug for alleviating memory impairment in rats after chronic stress and protecting synapses in the hippocampus of stressed rats.

14.
BMC Pediatr ; 20(1): 422, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887572

RESUMO

BACKGROUND: Diaphragmatic dysfunction (DD) has a great negative impact on clinical outcomes, and it is a well-recognized complication in adult patients with critical illness. However, DD is largely unexplored in the critically ill pediatric population. The aim of this study was to identify risk factors associated with DD, and to investigate the effects of DD on clinical outcomes among critically ill children. METHODS: Diaphragmatic function was assessed by diaphragm ultrasound. According to the result of diaphragmatic ultrasound, all enrolled subjects were categorized into the DD group (n = 24) and the non-DD group (n = 46). Collection of sample characteristics in both groups include age, sex, height, weight, primary diagnosis, complications, laboratory findings, medications, ventilatory time and clinical outcomes. RESULTS: The incidence of DD in this PICU was 34.3%. The level of CRP at discharge (P = 0.003) in the DD group was higher than the non-DD group, and duration of elevated C-reactive protein (CRP) (P < 0.001), sedative days (P = 0.008) and ventilatory treatment time (P < 0.001) in the DD group was significantly longer than the non-DD group. Ventilatory treatment time and duration of elevated CRP were independently risk factors associated with DD. Patients in the DD group had longer PICU length of stay, higher rate of weaning or extubation failure and higher mortality. CONCLUSION: DD is associated with poorer clinical outcomes in critically ill childern, which include a longer PICU length of stay, higher rate of weaning or extubation failure and a higher mortality. The ventilatory treatment time and duration of elevated CRP are main risk factors of DD in critically ill children. TRIAL REGISTRATION: Current Controlled Trials ChiCTR1800020196 , Registered 01 Dec 2018.

15.
Urol Oncol ; 2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32900630

RESUMO

OBJECTIVES: To evaluate the prognostic impact of lymphovascular invasion (LVI) on node-negative upper tract urothelial carcinoma (UTUC) in patients treated with radical nephroureterectomy (RNU). MATERIALS AND METHODS: A retrospective study was performed in single tertiary referral center of middle Taiwan between 2001 and 2015. Seven hundred and twenty-eight patients were diagnosed of UTUC and underwent RNU with ipsilateral bladder cuff excision including 303 and 195 patients with N0 and Nx status respectively. LVI status was assessed as a prognostic factor for cancer-specific (CSS) and overall survival (OS) using univariate and multivariate Cox regression analysis. RESULTS: LVI was observed in 82 patients (16.5%). LVI presentation associated with smoking status, advanced tumor stage, high tumor grade, positive surgical margin, and consequence lung/liver/bone metastasis. In the multivariate analysis, LVI was failed to predict CSS, OS, and disease-free survival (DFS) (hazard ratio [HR] [95% confidence interval [CI]: 1.07 [0.55-2.09], 1.05 [0.62-1.79], 1.15 [0.69-1.92], in CSS, OS, DFS, respectively). In the subgroup analysis of pT1-2 disease, the CSS, OS, and DFS were associated with LVI status (HR [95% CI]: 2.29 [0.44-11.84], 3.17 [1.16-8.67], 2.66 [1.04-6.79], in CSS, OS, DFS, respectively). In contrast, there was no difference in pT3 disease. CONCLUSION: In conclusion, LVI status was not associated with survival outcomes of node-negative UTUC in our study. The subgroup analysis showed different prognostic impacts of LVI status in node-negative UTUC with T1-2 and T3 stage. Further evidence to clarify the prognostic effect is needed to make LVI became a practical factor in clinical decision-making.

16.
Disabil Rehabil ; : 1-5, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32903114

RESUMO

OBJECTIVE: To compare the test-retest reliability and random measurement errors of the Barthel Index (BI) and modified Barthel Index (MBI) in patients with chronic stroke. METHOD: The intraclass correlation coefficient (ICC) and the minimal detectable change (MDC) were applied respectively to examine the test-retest reliability (about 2 weeks apart) and the random measurement errors. The MDC% was used to adjust the cut-off score for determining whether a real change had been achieved, if heteroscedasticity existed. RESULTS: A total of 60 patients participated. The BI and MBI both had high ICCs (0.94 and 0.94, respectively) with small MDCs (16.2 and 15.4, respectively) and MDC%s (21.2% and 19.0%, respectively), indicating that both measures have comparable reliability in repeated assessments. However, moderate associations (r = -0.47 for the BI and -0.59 for the MBI) were found between the means of tests and retests and the absolute values of change scores, indicating heteroscedasticity. These findings suggest that a fixed MDC value is not appropriate for determining the real change in both measures because the amount of random measurement error varies with the patients' ADL function. CONCLUSION: The MBI, which showed excellent test-retest reliability and relatively lower random measurement error than the BI, appears to be a better ADL measure. The MDC% adjusted value is recommended to determine whether the change scores are beyond random measurement error. IMPLICATIONS FOR REHABILITATION The MBI is recommended for clinical and research applications because it has better test-retest reliability and relatively lower random measurement error than those of the original BI. The MDC% adjusted value is recommended to determine whether the change scores are beyond random measurement error when the MBI or the BI is used.

17.
Environ Res ; : 110196, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32919957

RESUMO

Biologically synthesized palladium nanoparticles (bio-Pd) have attracted considerable interest as promising green catalysts for environmental remediation. However, the mechanisms by which microorganisms produce bio-Pd remain unclear. In the present study, we investigated the roles of Shewanella oneidensis MR-1 and its NADH dehydrogenases and hydrogenases (HydA and HyaB) in bio-Pd production using formate as the electron donor. The roles of NADH dehydrogenases and hydrogenases were studied by inhibiting NADH dehydrogenases and using hydrogenase mutants (ΔhydA, ΔhyaB, and ΔhydAΔhyaB), respectively. The results showed ∼97% reduction of palladium by S. oneidensis MR-1 after 24 h using 250 µM palladium and 500 µM formate. Electron microscopy images showed the presence of bio-Pd on both the outer and cytoplasmic membranes of S. oneidensis MR-1. However, the inhibition of NADH dehydrogenases in S. oneidensis MR-1 resulted in only ∼61% reduction of palladium after 24 h, and bio-Pd were not found on the outer membrane. The mutants lacking one or two hydrogenases removed 91-96% of palladium ions after 24 h and showed more cytoplasmic bio-Pd but less periplasmic bio-Pd. To the best of our knowledge, this is the first study to demonstrate the role of NADH dehydrogenases of S. oneidensis MR-1 in the formation of bio-Pd on the outer membrane. It also demonstrates that the hydrogenases (especially HyaB) of S. oneidensis MR-1 contribute to the formation of bio-Pd in the periplasmic space. This study provides mechanistic insights into the production of biogenic metal nanoparticles towards their possible use in industrial and environmental applications.

18.
J Chromatogr A ; 1630: 461577, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32980610

RESUMO

Polycyclic aromatic sulfur heterocycles (PASHs), as a group of major sulfur-containing compounds, widely occur in crude oil and its refined products. Accurate analyses of these petrochemical components play an important role in monitoring oil quality, forensic source identification, and assessment of environmental impact of an oil spill. PASHs occur at relatively lower abundances in most crude oils and refined petroleum products than their corresponding aromatic hydrocarbons and are co-eluted together with some petroleum hydrocarbons in chromatographic analysis, resulting in high uncertainty for their quantitation. Capillary gas chromatography coupled with a quadrupole time-of-flight mass spectrometry (GC-QTOF-MS) provides high resolution and high mass accuracy, which facilitates discrimination of the delicate mass defects of isobaric compounds with the same nominal mass and external matrix material. In this work, GC-QTOF-MS was applied to analyze bicyclic to pentacyclic PASHs including benzothiophenes, dibenzothiophenes, benzonaphthothiophenes, dinaphthothiophenes and their C1- to C4- alkylated homologues in a number of crude oils, refined petroleum products, and environmental samples. GC-QTOF-MS analysis substantially improved the identification confidence and reduced quantitation uncertainty of PASHs and polycyclic aromatic hydrocarbons (PAHs) by eliminating the interferences presented in nominal mass chromatograms.

19.
Immunology ; 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32876334

RESUMO

Hydrogen sulphide (H2 S) is the latest identified small gaseous mediator enabled by its lipophilic nature to freely permeate the biological membranes. Initially, H2 S was recognized by its roles in neuronal activity and vascular relaxation, which makes it an important molecule involved in paracrine signalling pathways. Recently, the immune regulatory function of gasotransmitters, H2 S in particular, is increasingly being appreciated. Endogenous H2 S level has been linked to macrophage activation, polarization and inflammasome formation. Mechanistically, H2 S-induced protein S-sulphydration suppresses several inflammatory pathways including NF-κB and JNK signalling. Moreover, H2 S serves as a potent cellular redox regulator to modulate epigenetic alterations and to promote mitochondrial biogenesis in macrophages. Here in this review, we intend to summarize the recent advancements of H2 S studies in macrophages, and to discuss with focus on the therapeutic potential of H2 S donors by targeting macrophages. The feasibility of H2 S signalling component as a macrophage biomarker under disease conditions would be also discussed.

20.
Artigo em Inglês | MEDLINE | ID: mdl-32825300

RESUMO

The high turnover rate of new generation employees is becoming an increasingly important issue for business and academia. Based on self-determination theory and conservation of resource theory, our study explores the impact of the inclusive talent development model on the turnover intention of new generation employees and the mediating role of work passion. Based on the questionnaire of 290 new generation employees' data from China, after common method biases and reliability and validity tests, we used SPSS, Mplus and bootstrapping for empirical analysis. The result showed that the inclusive talent development model includes the diversified talent team construction, rational tolerance of employee's opinions and failures, emphasis on employee's training, emphasis on fairness and win-win and emphasis on employee's advantages. The work passion has been divided into harmonious passion and obsessive passion. Among them, rational tolerance of employee's opinions and failures, emphasis on employee's training and emphasis on fairness and win-win have a significant positive impact on harmonious passion. Emphasis on fairness and win-win and emphasis on employee's advantages have negative correlation with obsessive passion. The employee's harmonious passion is significantly negatively correlated with the turnover intention and the obsessive passion is significantly positively correlated with the turnover intention. In addition, the harmonious passion plays a mediating role between rational tolerance of employee's opinions and failures, emphasis on employee's training, emphasis on fairness and win-win and employee's turnover intention, while the obsessive passion plays a mediating role between emphasis on fairness and win-win and emphasis on employee's advantages and employee's turnover intention.

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