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1.
J Pharm Biomed Anal ; 177: 112856, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31521020

RESUMO

Daphne genkwa Sieb. et Zucc., as a traditional oriental herb, has been widely distributed and employed in China. The major bioactive components in D. genkwa are flavonoid compounds, which showed pharmacological activities such as anti-inflammatory, analgesic, anti-tumor and immunomodulatory activities. In this study, we analyzed total flavonoids in D. genkwa and their metabolites in normal and adjuvant arthritis (AA) rat plasma, urine and feces samples by liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS). A total of 4 metabolites in plasma, 9 metabolites in urine and 15 metabolites in feces were characterized respectively by LC-Q-TOF-MS technology in normal rat. And 9 of the metabolites were observed in the AA rat urine, while there was no prototype drug or its metabolites detected in plasma and fecal samples. The metabolic pathway mainly involves hydroxylation, methylation, glucuronide, sulfate conjugation, oxidation and reduction, during the phase I and phase II biotransformation pathway. All the information gained here will be greatly helpful in elucidating the potential biological and pharmacological mechanism of flavonoid in D. genkwa, thus providing new ideas for drug development.

2.
J Nanosci Nanotechnol ; 20(6): 3356-3360, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748027

RESUMO

We report the formation of gold nanoparticles on indium tin oxide conducting glass (ITO) surface via electrodeposition method at room temperature. The prepared nano-Au electrodes has been fabricated for sensitive detection of Pb2+, and showed highly selective response toward Pb2+. The electrochemical detection of Pb2+ were determined by differential pulse stripping voltammetric (DPSV). The nano-Au electrochemical sensor could detect Pb2+ from 0.5 to 10 µM with detection limits of 0.06 µM (S/N= 3) and sensitivity of 0.27996 mA µM-1. The proposed sensor is simple, reliable, sensitive, selective, and low-cost, thus holds potential for practical application in Pb2+ detection.

3.
J Cell Physiol ; 235(2): 1405-1416, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31347176

RESUMO

Breast cancer patients with high expression of aldehyde dehydrogenases (ALDHs) cell population have higher tolerability to chemotherapy since the cells posses a characteristic of breast cancer stem cells (BCSCs) that are resistant to conventional chemotherapy. In this study, we found that the ALDH-positive cells were higher in CD44+ CD24- and CD44+ CD24- ESA+ BCSCs than that in both BT549 and MDA-MB-231 cell lines but microRNA-7 (miR-7) level was lower in CD44+ CD24- and CD44+ CD24- ESA+ BCSCs than that in MDA-MB-231 cells. Moreover, miR-7 overexpression in MDA-MB-231 cells decreased ALDH1A3 activity by miR-7 directly binding to the 3'-untranslated region of ALDH1A3; while the ALDH1A3 expression was downregulated in MDA-MB-231 cells, the expressions of CD44 and Epithelium Specific Antigen (ESA) were reduced along with decreasing the BCSC subpopulation. Significantly, enforced expression of miR-7 in CD44+ CD24- ESA+ BCSC markedly inhibited the BCSC-driven xenograft growth in mice by decreasing an expression of ALDH1A3. Collectively, the findings demonstrate the miR-7 inhibits breast cancer growth via suppressing ALDH1A3 activity concomitant with decreasing BCSC subpopulation. This approach may be considered for an investigation on clinical treatment of breast cancers.

4.
Enzyme Microb Technol ; 132: 109436, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31731954

RESUMO

The halophilic green alga Dunaliella bardawil has been used for commercial production of natural ß-carotene by large-scale outdoor cultivation, which often suffers from heat stress especially at noon in hot summers. In this study, the effects of heat stress on cell growth, pigment contents, and activities of antioxidant system in D. bardawil were studied, and RNA-seq experiment was conducted to analyze the transcriptional response to heat stress (42 °C for 2 h) in D. bardawil. High temperature (42 °C) for short time treatment (≤3 h) did not severely affect the cell growth and pigment accumulation of D. bardawil. Multiple genes encoding heat shock proteins for protein folding and antioxidant enzymes against toxic reactive oxygen species were substantially up-regulated significantly under heat stress. D. bardawil cells tended to shift from aerobic to glycolytic metabolism for energy production to increase survival chances under heat stress. Furthermore, the enrichment of ascorbate-glutathione cycle, up-regulation of genes responsible for chloroplast membranes, and changes in lipid characteristics like carbon chain length and unsaturation degree could play a vital role in achieving thermotolerance of D. bardawil. Taken together, this study improved our understanding of the molecular mechanisms of heat stress responses in D. bardawil.

5.
Water Res ; 169: 115155, 2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31671296

RESUMO

Enhancing biogas production, while avoiding inhibition of methanogenesis during co-digestion of grease interceptor waste (GIW), can help water resource recovery facilities reduce their carbon footprint. Here we used pre-adapted and non-adapted digesters to link microbial community structure to digester function. Before disturbance, the pre-adapted and non-adapted digesters showed similar methane production and microbial community diversity but dissimilar community composition. When exposed to an identical disturbance, the pre-adapted digester achieved better performance, while the non-adapted digester was inhibited. When re-exposed to disturbance after recovery, communities and performance of both digesters converged, regardless of the temporal variations. Co-digestion of up to 75% GIW added on a volatile solids (VS) basis was achieved, increasing methane yield by 336% from 0.180 to 0.785 l-methane/g-VS-added, the highest methane yield reported to date for lipid-rich waste. Progressive perturbation substantially enriched fatty acid-degrading Syntrophomonas from less than 1% to 24.6% of total 16S rRNA gene sequences, acetoclastic Methanosaeta from 2.3% to 11.9%, and hydrogenotrophic Methanospirillum from less than 1% to 6.6% in the pre-adapted digester. Specific hydrolytic and fermentative populations also increased. These ecological insights demonstrated how progressive perturbation can be strategically used to influence methanogenic microbiomes and improve co-digestion of GIW.

6.
Adv Exp Med Biol ; 1209: 23-41, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31728863

RESUMO

The highly conserved catabolic process of autophagy delivers unwanted proteins or damaged organelles to vacuoles for degradation and recycling. This is essential for the regulation of cellular homeostasis, stress adaptation, and programmed cell death in eukaryotes. In particular, emerging evidence indicates that autophagy plays a multifunctional regulatory role in plant innate immunity during plant-pathogen interactions. In this review, we highlight existing knowledge regarding the involvement of autophagy in plant immunity, mechanisms functioning in the induction of autophagy upon pathogen infection, and possible directions for future research.


Assuntos
Autofagia , Imunidade Vegetal , Homeostase , Imunidade Vegetal/imunologia , Vacúolos
8.
Dalton Trans ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31773120

RESUMO

Covalent organic frameworks (COFs) have been utilized as molecular sieves to adsorb or remove or separate a wide range of substances. Herein, a new carboxyl-containing COF (COF-COOH) is fabricated from the polymerization of 1,3,5-triformylphloroglucinol (TP) and 4,4'-diamino-[1,1'-biphenyl]-3,3'-dicarboxylic acid (DBA). COF-COOH displays good adsorption performance on Congo red (CR) through hydrogen bonds and π-π stacking interactions. Through post-modification with Ca2+/Ni2+ ions, the adsorption capacity of COF-COOCa/COF-COONi to CR is improved, which is due to the coordinated metal cations having a positive contribution to the electrostatic interactions. At 25 °C, the maximum adsorption amount of COF-COOCa and COF-COONi to CR is 704.23 mg g-1 and 781.25 mg g-1, respectively. The removal efficiency of COF-COOCa to CR is 95% and that of COF-COONi is 96%. This demonstrates that the new metal ion-assisted COFs are viable adsorbents to remove dye pollutants, which are harmful to the environment and to human health, from wastewater.

9.
Small ; : e1904589, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31778039

RESUMO

In this work, expanded MoS2 nanosheets grown on nitrogen-doped branched TiO2 /C nanofibers (NBT/C@MoS2 NFs) are prepared through electrospinning and hydrothermal treatment method as anode materials for sodium-ion batteries (SIBs). The continuous 1D branched TiO2 /C nanofibers provide a large surface area to grow expanded MoS2 nanosheets and enhance the electronic conductivity and cycling stability of the electrode. The large surface area and doping of nitrogen can facilitate the transfer of both Na+ ions and electrons. With the merits of these unique design and extrinsic pseudocapacitance behavior, the NBT/C@MoS2 NFs can deliver ultralong cycle stability of 448.2 mA h g-1 at 200 mA g-1 after 600 cycles. Even at a high rate of 2000 mA g-1 , a reversible capacity of 258.3 mA h g-1 can still be achieved. The kinetic analysis demonstrates that pseudocapacitive contribution is the major factor to achieve excellent rate performance. The rational design and excellent electrochemical performance endow the NBT/C@MoS2 NFs with potentials as promising anode materials for SIBs.

10.
Cardiovasc Pathol ; 44: 107159, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31743871

RESUMO

Trastuzumab-mediated cardiotoxicity poses a significant challenge in the treatment of human epidermal growth factor receptor 2-positive breast cancer. To understand the underlying mechanisms, we conducted experiments to determine ultrastructural changes of rabbit cardiac tissue under different experimental conditions, including differing doses of trastuzumab and supplementation with oral sodium selenite, an antioxidant. Histopathology revealed lymphocyte and macrophage infiltration in myocardium of rabbits receiving four doses of trastuzumab. Transmission electron microscopy showed substantial changes with trastuzumab, including edema with separation of myofibril bundles and rupture of sarcomeres. Within mitochondria, edema resulted in disorganization of the cristae. Some mitochondria exhibited eccentric projections of their membranes with disruption of both inner and outer membranes. These changes were seen to a lesser extent in rabbits who received oral sodium selenite prior to trastuzumab. Selenium is integral to functioning of mitochondrial glutathione peroxidases, important antioxidants that also maintain membrane integrity. If mitochondria are disrupted as part of trastuzumab cardiac toxicity, selenium supplementation might be an important therapeutic or preventive consideration. Larger studies to explore this hypothesis are warranted.

11.
Medicine (Baltimore) ; 98(48): e18025, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31770216

RESUMO

INTRODUCTION: Sepsis is a physiological, pathological, and biochemical syndrome caused by infection. Acupuncture may be useful for sepsis. This systematic review aims to assess the efficacy and safety of acupuncture as a complementary therapy for sepsis. METHODS AND ANALYSIS: We will search PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure (CNKI), Wan Fang Database, Chinese Biomedicine (CBM) database, VIP database, and TCM Literature Analysis and Retrieval Database from inception to October 31, 2019 to identify any eligible study. We include all randomized controlled trials (RCTs) without any limitation of blinding or publication language, exclude cohort studies and case reports. Two reviewers will independently select studies, extract and manage data. The primary outcomes include the mortality at 28 days, acute physiology, and chronic health evaluation II scores. The secondary outcomes include the tumor necrosis factor α (TNF-α) counts, interleukin 6 (IL-6) counts, interleukin 10 (IL-10) counts, procalcitonin (PCT), lactic acid, the level of T cell subsets (CD3+, CD4+, CD8+, CD4+/CD8+), monocytes of human leukocyte antigen DR (HLA-DR), C-reactive protein (CRP), the numeration of leukocyte, intra-abdominal pressure, and adverse events or reactions. Statistical analyses will be performed using the Review Manager V.5.3 and R packages Metafor. We will use the Cochrane risk of bias tool for randomized trials to assess the risk of bias of included studies. ETHICS AND DISSEMINATION: This study will not involve personal information. Ethical approval will not be required. We will publish the results in a peer-reviewed journal. PROSPERO TRIAL REGISTRATION NUMBER: CRD42019141491.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31770344

RESUMO

STUDY DESIGN: This is an in vitro biomechanical study. OBJECTIVE: This study aimed to investigate the biomechanical variations of lumbar spine motor units after bilateral facet joint severe violation in cadaver specimens and analyze the biomechanics under different moments. SUMMARY OF BACKGROUND DATA: The incidence of facet joint violation (FJV) is highly variable, and one of the most important factors is the lack of awareness of protection. Until now, the biomechanical effects of FJV remains unclear. METHODS: Biomechanical testing was performed on 12 human cadaveric spines under flexion-extension, lateral bending, and axial rotation loading. After intact analysis, pedicle screws were inserted at L5, and the biomechanical testing was repeated. Full range of motion (ROM) at the proximal adjacent levels under different moments was recorded and normalized to the intact (100%) noninstrumented spine. The relative ROM changes were compared between the control and severe violation groups. RESULTS: The adjacent-level ROM (flexion-extension, lateral bending, axial rotation) did not change significantly in the control group at each moment (7.5, 6.0, 4.5 N m) compared with the intact noninstrumented spine. In the severe violation group, the supradjacent-level ROM decreased significantly under all moments relative to the intact noninstrumented spine (P < 0.05) except for the ROM of lateral bending at moments of 7.5 and 6.0 N m. When comparing the ROM between the two groups, there were significant differences in all movements except lateral bending at 7.5 N m. CONCLUSIONS: When superior-segment bilateral facet joints are severely violated by screws, the flexion-extension and axial rotation ROM of adjacent vertebrae decreases at each moment (7.5, 6.0, 4.5 N m), and the lateral bending ROM decreases at 4.5 N m. LEVEL OF EVIDENCE: N/A.

13.
Ann Nutr Metab ; : 1-8, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31775140

RESUMO

OBJECTIVE: Asprosin, a novel peptide that has recently discovered as an important regulatory adipokine, is relevant to obesity in animals and adult humans. Little is known about its roles in children. The aim of the current study was to determine the potential role of asprosin and explore its relationship to various obesity-related markers in children with obesity. METHODS: A cross-sectional study was conducted among 119 Chinese children, including 79 children with obesity and 40 lean controls. Anthropometric parameters, clinical data, and circulating tumor necrosis factor-α (TNF-α), adiponectin, leptin, and asprosin levels were measured. RESULTS: Serum asprosin concentrations were significantly elevated in children with obesity compared with lean controls. Children with insulin resistance (IR) had higher asprosin levels than non-IR group. Asprosin was positively correlated with waist-to-hip ratio (WHR), diastolic blood pressure, homoeostasis model of IR (HOMA-IR), leptin-to-adiponectin ratio, TNF-α independent of their body mass index, SDs score, and age. In multivariable linear regression analysis, WHR and HOMA-IR were associated with the circulating level of asprosin. CONCLUSIONS: Circulating asprosins are increased in children with obesity and associated with IR. It may be proposed as a novel marker to predict advanced disease.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31751247

RESUMO

In this paper, we take as inspiration the labor division into scouts and workers in an ant colony and propose a novel approach for automated cell tracking in the framework of multi-Bernoulli random finite sets. To approximate the Bernoulli parameter sets, we first define an existence probability of an ant colony as well as its discrete density distribution. During foraging, the behavior of scouts is modeled as a chaotic movement to produce a set of potential candidates. Afterwards, a group of workers, a worker ant colony, is recruited for each candidate, which then embark on gathering heuristic information in a self-organized way. Finally, the pheromone field is formed by the corresponding worker ant colony, from which the Bernoulli parameter is derived and the state of the cell is estimated accordingly to be associated with the existing tracks. Performance comparisons with other previous approaches are conducted on both simulated and real cell image sequences and show the superiority of this algorithm.

15.
Dentomaxillofac Radiol ; : 20190280, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31718273

RESUMO

OBJECTIVE: The objective of this study was to determine whether the trabecular volumetric Bone Mineral Density (vBMD) of the middle, body and angle of the mandible correlates with vBMD of the cervical and lumbar vertebrae in a Chinese population. METHODS AND MATERIALS: 661 subjects (270 males, 391 females), ranging from 20 to 59 years of age, were recruited for vBMD measurements by quantitative CT (QCT). Basic information (age, height and weight), vBMD of the mandible (middle, body and angle sites), and vBMD of the cervical and lumbar vertebrae were recorded. Spearman's rank correlation test was used to investigate the association of mandibular with vertebral vBMD. RESULTS: The study cohort comprised 661 subjects: 270 (41%) males, 391 (59%) females. Median age in males was 40 (range, 21-59) years. Median age in females was 41 (range, 20-59) years. Values of the Spearman correlation coefficient between mandibular and vertebral vBMD ranged from R = 0.048 to 0.141. In males, the three correlation coefficients between mandibular and cervical vBMD (middle: R = 0.138; body: R = 0.126; angle: R = 0.122) were all statistically significant (p < 0.05). In females, the correlation between the middle mandibular site and cervical site was statistically significant (R = 0.141, p < 0.01). None of the other correlations examined were statistically significant. CONCLUSION: In this study population, mandibular vBMD was at best weakly correlated with cervical and lumbar vertebral vBMD, indicating that mandibular vBMD should be measured independently for the assessment of mandibular bone status.

16.
Sci Rep ; 9(1): 16691, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31723231

RESUMO

Coagulation is a critical process in the assembly of cellulose nanofibrils into filaments by wet spinning; however, so far, the role of the coagulation solvent has not been systematically elucidated in this context. This work considers organic non-solvents (ethanol, acetone) and aqueous electrolyte solutions (NaCl(aq), HCl(aq), CaCl2(aq)) for the coagulation of negatively charged cellulose nanofibrils via wet spinning. The associated mechanisms of coagulation with such non-solvents resulted in different spinnability, coagulation and drying time. The properties of the achieved filaments varied depending strongly on the coagulant used: filaments obtained from electrolytes (using Ca2+ and H+ as counterions) demonstrated better water/moisture stability and thermomechanical properties. In contrast, the filaments formed from organic non-solvents (with Na+ as counterions) showed high moisture sorption and low hornification when subjected to cycles of high and low humidity (dynamic vapor sorption experiments) and swelled extensively upon immersion in water. Our observations highlight the critical role of counter-ions and non-solvents in filament formation and performance. Some of the fundamental aspects are further revealed by using quartz crystal microgravimetry with model films of nanocelluloses subjected to the respective solvent exchange.

17.
J Occup Environ Med ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31743304

RESUMO

OBJECTIVE: To evaluate interaction of HLA-DPß1 and DRß1 polymorphisms with metrics of beryllium exposure, in the development of beryllium sensitization (BeS) and chronic beryllium disease (CBD). METHODS: A matched case-control study of 61 CBD, 41 BeS, and 259 controls from two beryllium-processing facilities. RESULTS: BES and CBD were significantly associated with presence of DPßE69. Dose response of exposure was not observed for the development of BES and CBD with/without adjustment for DPßE69 (p > 0.05). The DRßE71 polymorphism was more common in BeS than CBD after adjusting for exposure and maybe a protective factor (aOR 0.4, 95% CI 0.2-0.9) against the progression of BeS to CBD. CONCLUSION: No exposure-response association was found, which may reflect that the workers in this high exposure cohort were above a threshold level where an exposure-response could be observed.

18.
BMJ Open ; 9(11): e028736, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31712332

RESUMO

OBJECTIVES: Recent data relating to the association between spicy food intake frequency and abdominal obesity are limited, especially in low-income areas. Therefore, the study explored the relationship between spicy food intake frequency and abdominal obesity, and assessed the role of energy intake as a mediator of these associations in a rural Chinese adult population. DESIGN: Cross-sectional study. SETTING: Rural Chinese adult population. PARTICIPANTS: Subjects from Henan Rural Cohort Study (n=28 773). PRIMARY OUTCOME MEASURES: The effects of spicy food intake frequency on abdominal obesity were analysed by restricted cubic spline and logistic regression, and the mediation effect was analysed using the bootstrap method. RESULTS: The adjusted percentages of abdominal obesity were 47.32%, 51.93%, 50.66% and 50.29% in the spicy food intake subgroups of never, 1-2 day/week, 3-5 day/week and 6-7 day/week, respectively. An inverse U-shaped association was found between spicy food intake frequency and abdominal obesity (p<0.01). Compared with subjects who never consumed spicy food, the adjusted ORs (95% CIs) in the 1-2 day/week, 3-5 day/week and 6-7 day/week subgroups were 1.186 (1.093, 1.287), 1.127 (1.038, 1.224) and 1.104 (1.044, 1.169), respectively. Furthermore, the increased odd of abdominal obesity related to more frequent spicy food intake was mediated by higher fat energy intake; the direct and indirect effects were 1.107 (1.053, 1.164) and 1.007 (1.003, 1.012), respectively. CONCLUSIONS: The data indicated that spicy food intake increased the risk of abdominal obesity, and fat energy intake may be a mediator of this association in rural Chinese populations. Clarifying the mechanisms will facilitate the development of novel preventive and therapeutic approaches for abdominal obesity. TRIAL REGISTRATION NUMBER: ChiCTR-OOC-15006699.

19.
Adv Mater ; : e1905210, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31714630

RESUMO

Chalcopyrite compound CuGaTe2 is the focus of much research interest due to its high power factor. However, its high intrinsic lattice thermal conductivity seriously impedes the promotion of its thermoelectric performance. Here, it is shown that through alloying of isoelectronic elements In and Ag in CuGaTe2 , a quinary alloy compound system Cu1- x Agx Ga0.4 In0.6 Te2 (0 ≤ x ≤ 0.4) with complex nanosized strain domain structure is prepared. Due to strong phonon scattering mainly by this domain structure, thermal conductivity (at 300 K) drops from 6.1 W m-1 K-1 for the host compound to 1.5 W m-1 K-1 for the sample with x = 0.4. As a result, the optimized chalcopyrite sample Cu0.7 Ag0.3 Ga0.4 In0.6 Te2 presents an outstanding performance, with record-high figure of merit (ZT) reaching 1.64 (at 873 K) and average ZT reaching 0.73 (between ≈300 and 873 K), which are ≈37 and ≈35% larger than the corresponding values for pristine CuGaTe2 , respectively, demonstrating that such domain structure arising from isoelectronic multielement alloying in chalcopyrite compound can effectively suppress its thermal conductivity and elevate its thermoelectric performance remarkably.

20.
Med Sci Monit ; 25: 8221-8229, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31676746

RESUMO

BACKGROUND The prevalence of food allergies in asthmatic children and adolescents has significantly increased over recent years. Nevertheless, the relevant clinical analyses are still lacking in China. Therefore, the present study aimed to determine common food allergens in pediatric patients with asthma in Chongqing, Southwest China. MATERIAL AND METHODS A total of 8393 asthmatic patients from Children's Hospital of Chongqing Medical University (CHCMU) were enrolled in this retrospective study between October 2014 and July 2017. All patients underwent skin prick test (SPT) with 10 food allergens and recorded history of clinical reactivity. The correlations among the positive rates, categories of allergens, gender, age, and living environment were analyzed. RESULTS A total of 2544 patients (30.31%) had a positive SPT, while the prevalence of food allergy was 8%. Sea crab, peanut, and sea shrimp were the most common food allergens found in the studied population. The frequent food allergies were sea crab, peanuts, and sea shrimp. CONCLUSIONS Identifying allergens is important for the diagnosis and management of allergic disorders, and for performing immunotherapy.

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