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2.
J Colloid Interface Sci ; 571: 100-108, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32182495

RESUMO

The cellulose, which is one of the most abundant solid by-products of agriculture and forestry industry, has been successfully tested for the synthesis of nitrogen and phosphorus co-doped carbon-based metal-free catalysts (NPC) via freeze-drying the mixture of cellulose crystallite and ammonium phosphate, followed by annealing of the hydrogel under nitrogen atmosphere at 800 °C for 2 h. Different techniques including TEM, SEM, FTIR and XPS spectroscopy have been applied to characterize the as-prepared NPC, which presents flake-like morphology with N and P doping levels of 4.3 atom% and 10.66 atom%, respectively. The NPC exhibits excellent catalytic activity for the reduction of p-nitrophenol (p-NP). The turnover frequency (TOF) of the reduction of p-NP is as high as 2 × 10-5 mmol·mg-1·min-1 and the apparent kinetic rate constant was calculated as 0.0394 min-1 at room temperature. The catalytic mechanism is proposed by combining the density functional theory calculation and analysis of the experimental results. These findings open up new possibilities of valorization for cellulose-based by-product and treatment of p-NP-based wastewater.

4.
Microbiologyopen ; : e1004, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32045512

RESUMO

Environment has a potential effect on the animal symbiotic microbiome. Here, to study the potential relationship of the symbiotic microbiomes of wild amphibians with altitude, we collected the gut and skin samples from frogs (nine species) and the environmental samples (water and soil samples) from the Leshan Mountains (altitude: 360-410 m) and Gongga Mountains (altitude: 3340-3989 m) on the eastern edge of the Tibetan Plateau. Bufo gargarizans (Bg) samples were collected from both the Leshan and Gongga mountain regions (Bg was the only species sampled on both mountains). The DNA extracted from each sample was performed high-throughput sequencing (MiSeq) of bacterial 16S rRNA gene amplicons. High relative abundance of Caulobacteraceae and Sphingomonadaceae was found in skin samples from both Bg and the other high-altitude amphibians (nine species combined). High relative abundance of Coxiellaceae and Mycoplasmataceae was found in gut samples from both Bg and the other high-altitude amphibians. Furthermore, the alpha and beta diversities of skin and gut samples from Bg and the other amphibian species (nine species combined) were similar. In terms of the symbiotic microbial community, the low-altitude samples were less diverse and more similar to each other than the high-altitude samples were. We speculated that extreme high-altitude environments and host phylogeny may affect the amphibian microbiome. Despite the distinct microbial community differences between the skin and gut microbiomes, some functions were similar in the Bg and combined high-altitude samples. The Bg and high-altitude skin samples had higher oxidative stress tolerance and biofilm formation than the low-altitude skin samples. However, the opposite results were observed for the Bg and high-altitude gut samples. Further study is required to determine whether these characteristics favor high-altitude amphibian adaptation to extreme environments.

5.
Nat Commun ; 11(1): 671, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015346

RESUMO

Dingoes are wild canids living in Australia, originating from domestic dogs. They have lived isolated from both the wild and the domestic ancestor, making them a unique model for studying feralization. Here, we sequence the genomes of 10 dingoes and 2 New Guinea Singing Dogs. Phylogenetic and demographic analyses show that dingoes originate from dogs in southern East Asia, which migrated via Island Southeast Asia to reach Australia around 8300 years ago, and subsequently diverged into a genetically distinct population. Selection analysis identifies 50 positively selected genes enriched in digestion and metabolism, indicating a diet change during feralization of dingoes. Thirteen of these genes have shifted allele frequencies compared to dogs but not compared to wolves. Functional assays show that an A-to-G mutation in ARHGEF7 decreases the endogenous expression, suggesting behavioral adaptations related to the transitions in environment. Our results indicate that the feralization of the dingo induced positive selection on genomic regions correlated to neurodevelopment, metabolism and reproduction, in adaptation to a wild environment.

6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(1): 153-159, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32027269

RESUMO

OBJECTIVE: To investigate the value of red blood cell distribution width (RDW) and fibrinogen (Fib) level for the evaluation of therapeutic efficacy and prognosis in patients with diffuse large B-cell lymphoma (DLBCL). METHODS: The relationship between RDW/Fib at initial diagnosis and efficacy and the clinical outcome was retro-spectively analyzed based on the study of 105 patients with DLBCL. The patients were divided into two groups: low RDW group (≤15%) and high RDW group (>15%), low Fib group (Fib≤4 g/L) and high Fib group (Fib>4 g/L) according to the normal values of RDW and Fib. Therapeutic efficacy, overall survival (OS) time and progression free survival (PFS) time were compared between two groups. The correlation between each factors and efficacy, prognosis was analyzed by univariate and multivariate regression. RESULTS: The therapeutic efficacy (P<0.001), OS time(P=0.004), and PFS time(P=0.007) were poorer in the high RDW group as compared with the low RDW group. The efficacy (P=0.015) and PFS time(P=0.04) were poorer in the high Fib group as compared with the low Fib group. Multivariate analysis showed that high RDW was the independent risk factor for efficacy of DLBCL patients (OR=3.394, 95% CI 1.093-10.539, P=0.035). CONCLUSION: High RDW and high Fib associate with poor efficacy in DLBCL patients.


Assuntos
Linfoma Difuso de Grandes Células B , Índices de Eritrócitos , Eritrócitos , Fibrinogênio , Humanos , Prognóstico , Estudos Retrospectivos
7.
Nat Plants ; 6(2): 143-153, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32055051

RESUMO

The spatiotemporal regulation of Ca2+ channels at the plasma membrane in response to extracellular signals is critical for development, stress response and reproduction, but is poorly understood. During flowering-plant reproduction, pollen tubes grow directionally to the ovule, which is guided by ovule-derived signals and dependent on Ca2+ dynamics. However, it is unknown how ovular signals are integrated with cytosolic Ca2+ dynamics in the pollen tube. Here, we show that MILDEW RESISTANCE LOCUS O 5 (MLO5), MLO9 and MLO15 are required for pollen tube responses to ovular signals in Arabidopsis thaliana. Phenotypically distinct from the ovule-bypass phenotype of previously identified mutants, mlo5 mlo9 double-mutant and mlo5 mlo9 mlo15 triple-mutant pollen tubes twist and pile up after sensing the ovular cues. Molecular studies reveal that MLO5 and MLO9 selectively recruit Ca2+ channel CNGC18-containing vesicles to the plasma membrane through the R-SNARE proteins VAMP721 and VAMP722 in trans mode. This study identifies members of the conserved seven transmembrane MLO family (expressed in the pollen tube) as tethering factors for Ca2+ channels, reveals a novel mechanism of molecular integration of extracellular ovular cues and selective exocytosis, and sheds light on the general regulation of MLO proteins in cell responses to environmental stimuli.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 231: 118110, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32007906

RESUMO

A morpholine-functionalized pyrrole-cyanine probe was synthesized via a simple condensation reaction in high yield. This probe exhibits high selectivity toward ClO- on fluorescence and UV-vis spectra in neat aqueous solution. The strong green emission of the probe solution was quenched and the yellow color faded immediately upon the addition of ClO-. The detection limit of the probe for ClO- was 0.165 µM. The mechanism of hypochlorite-induced CC breakage was supposed on the basis of EIS-MS, NMR, and density functional theory (DFT) calculation. Finally, the probe was utilized to image ClO- in lysosomes of living cells.

9.
Sci China Life Sci ; 63(3): 375-387, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32048161

RESUMO

Inflammatory leukocytes infiltration is orchestrated by mechanisms involving chemokines, selectins, addressins and other adhesion molecules derived from endothelial cells (ECs), but how they respond to inflammatory cues and coordinate leukocyte transmigration remain elusive. In this study, using hepatic ischemia/reperfusion injury (HIRI) as a model, we identified that endothelial Notch activation was rapidly and dynamically induced in liver sinusoidal endothelial cells (LSECs) in acute inflammation. In mice with EC-specific Notch activation (NICeCA), HIRI induced exacerbated liver damage. Consistently, endothelial Notch activation enhanced neutrophil infiltration and tumor necrosis factor (TNF)-α expression in HIRI. Transcriptome analysis and further qRT-PCR as well as immunofluorescence indicated that endomucin (EMCN), a negative regulator of leukocyte adhesion, was downregulated in LSECs from NICeCA mice. EMCN was downregulated during HIRI in wild-type mice and in vitro cultured ECs insulted by hypoxia/re-oxygenation injury. Notch activation in ECs led to increased neutrophil adhesion and transendothelial migration, which was abrogated by EMCN overexpression in vitro. In mice deficient of RBPj, the integrative transcription factor of canonical Notch signaling, although overwhelming sinusoidal malformation aggravated HIRI, the expression of EMCN was upregulated; and pharmaceutical Notch blockade in vitro also upregulated EMCN and inhibited transendothelial migration of neutrophils. The Notch activation-exaggerated HIRI was compromised by blocking LFA-1, which mediated leukocyte adherence by associating with EMCN. Therefore, endothelial Notch signaling controls neutrophil transmigration via EMCN to modulate acute inflammation in HIRI.

10.
Eur J Med Chem ; 191: 112115, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32105982

RESUMO

Adenylate cyclases (ACs), play a critical role in the conversion of adenosine triphosphate (ATP) into the second messenger cyclic adenosine monophosphate (cAMP). Studies have indicated that adenylyl cyclase type 2 (AC2) is potential drug target for many diseases, however, up to now, there is no AC2-selective agonist reported. In this research, docking-based virtual screening with the combination of cell-based biological assays have been performed for discovering novel potent and selective AC2 agonists. Virtual screening disclosed a novel hit compound 8 as an AC2 agonist with EC50 value of 8.10 µM on recombinant human hAC2 + HEK293 cells. The SAR (structure activity relationship) based on the derivatives of compound 8 was further explored on recombinant AC2 cells and compound 73 was found to be the most active agonist with the EC50 of 90 nM, which is 160-fold more potent than the reported agonist Forskolin and could selectively activate AC2 to inhibit the expression of Interleukin-6. The discovery of a new class of AC2-selective agonists would provide a novel chemical probe to study the physiological function of AC2.

11.
Biofabrication ; 12(2): 025032, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32084655

RESUMO

The fabrication technique determines the physicochemical and biological properties of scaffolds, including the porosity, mechanical strength, osteoconductivity, and bone regenerative potential. Biphasic calcium phosphate (BCP)-based scaffolds are superior in bone tissue engineering due to their suitable physicochemical and biological properties. We developed an indirect selective laser sintering (SLS) printing strategy to fabricate 3D microporous BCP scaffolds for bone tissue engineering purposes. The green part of the BCP scaffold was fabricated by SLS at a relevant low temperature in the presence of epoxy resin (EP), and the remaining EP was decomposed and eliminated by a subsequent sintering process to obtain the microporous BCP scaffolds. Physicochemical properties, cell adhesion, biocompatibility, in vitro osteogenic potential, and rabbit critical-size cranial bone defect healing potential of the scaffolds were extensively evaluated. This indirect SLS printing eliminated the drawbacks of conventional direct SLS printing at high working temperatures, i.e. wavy deformation of the scaffold, hydroxyapatite decomposition, and conversion of ß-tricalcium phosphate (TCP) to α-TCP. Among the scaffolds printed with various binder ratios (by weight) of BCP and EP, the scaffold with 50/50 binder ratio (S4) showed the highest mechanical strength and porosity with the smallest pore size. Scaffold S4 showed the highest effect on osteogenic differentiation of precursor cells in vitro, and this effect was ERK1/2 signaling-dependent. Scaffold S4 robustly promoted precursor cell homing, endogenous bone regeneration, and vascularization in rabbit critical-size cranial defects. In conclusion, BCP scaffolds fabricated by indirect SLS printing maintain the physicochemical properties of BCP and possess the capacity to recruit host precursor cells to the defect site and promote endogenous bone regeneration possibly via the activation of ERK1/2 signaling.

12.
Hemoglobin ; : 1-3, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31985312

RESUMO

We report a novel mutation on the ß-globin gene in a female of the Chinese population. This mutation produces a ß-globin variant that can be detected by the capillary electrophoresis (CE) method, but coelutes with Hb A2 by high performance liquid chromatography (HPLC). DNA sequencing showed a mutation of codon 46 and it was named Hb Cenxi [ß46(CD5)Gly→Arg (GGG>CGG), HBB: c.139G>C] for the city of birth of the proband. She presented normal hematological parameters.

13.
Mycologia ; 112(1): 185-196, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31900087

RESUMO

The genus Psiloboletinus was proposed by Rolf Singer in 1945 based on Phylloporus lariceti, a species that associates with Larix in the Altai Mountains of central and eastern Asia. However, this classification has been controversial due to the morphological similarity to known genera Boletinus and Fuscoboletinus. Because of the lack of fresh material to study, the phylogenetic position of Psiloboletinus has remained unknown since its publication. However, the recently described species Suillus foetidus reported from northeast China allows this issue to be reexamined and resolved. Through morphological observations and comparison, we find that S. foetidus is a heterotypic synonym of Ps. lariceti. Furthermore, Psiloboletinus should be retained as an independent genus sister to Suillus based on molecular phylogenetic evidence and morphological features.

15.
Chemosphere ; 246: 125828, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31927381

RESUMO

People are inevitably exposed to phthalates (PEs) ubiquitously existing in environment. Our previous studies, simulating the actual situations of people exposure to PEs, have shown that the sub-chronic exposure to low-doses PEs mixture (MIXPs) impaired reproductive function in male rats. Zinc is an important element in maintaining male reproductive functions. However, it is still unknown whether zinc supplement could mitigate PEs-induced male reproductive toxicity or not with sub-chronic low-dose mixture exposure. This study aimed to explore the effect of zinc supplement on the reproductive toxicity caused by sub-chronic MIXPs exposure (160 mg/(kg•body weight)/d, for 90 days) in male rats, and further to reveal the underlying mechanisms. Testosterone (T), FSH and LH in serum, early toxicity indicators in urine, PIWI proteins (PIWIL1 and PIWIL2) expression in testes and pathological examination were performed for toxicity evaluation. Steroidogenic proteins (17ß-HSD, StAR, CYP17A1, P450scc and SRD5A) were measured for mechanisms of exploration. The results indicated that zinc supplement could inhibit the T, LH, FSH level decreases in serum, abolish the effect of 5 early toxicity indicators' levels in urine, restrain the alteration of PIWI proteins expression and improve the constructional injury of testes. These effects might be relevant with the suppressed alteration of the expression of steroidogenic proteins induced by MIXPs in rat testicular cells. This work may offer further insights into reducing health risks of MIXPs exposure.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31963215

RESUMO

Demand calculation, which is the base of most logistics decisions and activities, is a critical work in humanitarian logistics (HL). However, previous studies on demand calculation in HL mainly focus on demand forecasting methodology, with many neglecting the checklist of critical supplies and practice background. This work proposes a new method for relief demand calculation by dividing the process into two parts: supply classification and demand calculation. A general method for classifying relief supplies and clarifying the checklist of relief items for multi-disaster and multiple natural scenarios is given in detail, followed by the procedure of demand calculation for each relief material. The authors present a case study to validate the feasibility and effectiveness of the proposed method based on the disaster response practice in China. Detailed lists of relief demand for different types and severities of disaster are provided.

17.
Int J Oncol ; 56(2): 606-617, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31894296

RESUMO

Abnormal metabolism serves a critical role in the development and progression of different types of malignancies including glioblastoma (GBM), and may therefore serve as a promising target for treatment of cancer. Preclinical studies have indicated that a ketogenic diet (KD) may exhibit beneficial effects in patients with GBM; however, the underlying mechanisms remain incompletely understood. The aim of the present study was to evaluate the effects of a KD on glioma stem­like cells (GSCs), by culturing patient­derived primary GSCs as well as a GSC cell line in glucose­restricted, ß­hydroxybutyrate­containing medium (BHB­Glow) which was used to mimic clinical KD treatment. GSCs cultured in BHB­Glow medium exhibited reduced proliferation and increased apoptosis compared with cells grown in the control medium. Furthermore, decreased expression of stem cell markers, diminished self­renewal in vitro, and reduced tumorigenic capacity in vivo, providing evidence that the stemness of GSCs was compromised. Mechanistically, culturing in BHB­Glow medium reduced glucose uptake and inhibited glycolysis in GSCs. Furthermore, culturing in the BHB­Glow medium resulted in morphological and functional disturbances to the mitochondria of GSCs. These metabolic changes may have reduced ATP production, promoted lactic acid accumulation, and thus, increased the production of reactive oxygen species (ROS) in GSCs. The expression levels and activation of mammalian target of rapamycin, hypoxia­inducible factor 1 and B­cell lymphoma 2 were decreased, consistent with the reduced proliferation of GSCs in BHB­Glow medium. ROS scavenging reversed the inhibitory effects of a KD on GSCs. Taken together, the results demonstrate that treatment with KD inhibited proliferation of GSCs, increased apoptosis and attenuated the stemness in GSCs by increasing ROS production.

18.
Electrophoresis ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900948

RESUMO

A novel method is reported to enhance the focusing of microparticle in the viscoelastic fluid. Gradually contracted geometry is designed in microchannel, which changes the distribution of the elastic lift force on the cross section. Additionally, it induces the viscous drag force and the Saffman lift force in the lateral direction. Under the combined effect of these forces, microparticles fast migrate to the center of the channel. In comparison to the channel with constant cross section, the present channel significantly enhances the particle's lateral migration, leading to efficient viscoelastic particle focusing in a short channel length. The influence of flow rate, channel length, particle size and fluid property on the particle focusing is also investigated. With simple structure, small footprint and perfect particle focusing performance, the present device has great potential in the particle focusing processes in various lab-on-a-chip applications.

19.
J Contin Educ Nurs ; 51(2): 87-96, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31978247

RESUMO

BACKGROUND: This study aimed to examine nurses' preferences for and attitudes toward e-learning, identify factors that motivated or discouraged their e-learning participation, and also find the relationship between the nurse's attitude and their characteristics. METHOD: A total of 534 RNs from eight hospitals in Shanghai were recruited. Data were collected using a questionnaire that consisted of e-learning experiences, barriers, motivating factors, learning preferences, and attitudes toward e-learning. RESULTS: Flexibility was the most important motivating factor and lack of time was the most common barrier to their participating in e-learning. Participants who had no e-learning experiences reported more barriers about lack of familiarity with e-learning and e-learning platforms. Nearly half of the participants exhibited positive attitudes toward e-learning. Regression analysis identified that nurses who were married, used computers frequently, and worked in rural hospitals were associated with more positive attitudes toward e-learning. CONCLUSION: Nurse educators and managers could provide more opportunities for nurses to increase their familiarity with online education technology and develop more high-quality online courses to meet nurses' learning needs. [J Contin Educ Nurs. 2020;51(2):87-96.].

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 230: 118025, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31927511

RESUMO

A quinoline-based hydrazone, namely, bis((quinolin-8-yl)methylene)carbonohydrazide (1), has been designed and synthesized, which could be used as a dual probe for selective recognition of Co2+ and Zn2+ by monitoring changes in absorption and fluorescence spectral pattern, respectively. The detection limits of 1 for these two ions are 0.21 and 0.66 µM, respectively. The complex formation between 1 and Co2+/Zn2+ is responsible for the detection process, as confirmed through several spectral methods and DFT calculations. The application of the as-synthesized sensor is demonstrated in Zn2+ imaging in living cells.

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