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1.
Cell Rep ; 34(13): 108922, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33789111

RESUMO

Hematopoietic stem cells (HSCs) regenerate blood cells upon hematopoietic injuries. During homeostasis, HSCs are maintained in a low reactive oxygen species (ROS) state to prevent exhaustion. However, the role of nitric oxide (NO) in controlling HSC regeneration is still unclear. Here, we find increased NO during HSC regeneration with an accumulation of protein aggregation. S-nitrosoglutathione reductase (GSNOR)-deleted HSCs exhibit a reduced reconstitution capacity and loss of self-renewal after chemotherapeutic injury, which is resolved by inhibition of NO synthesis. Deletion of GSNOR enhances protein S-nitrosylation, resulting in an accumulation of protein aggregation and activation of unfolded protein response (UPR). Treatment of taurocholic acid (TCA), a chemical chaperone, rescues the regeneration defect of Gsnor-/- HSCs after 5-fluorouracil (5-FU) treatment. Deletion of C/EBP homologous protein (Chop) restores the reconstitution capacity of Gsnor-/- HSCs. These findings establish a link between S-nitrosylation and protein aggregation in HSC in the context of blood regeneration.

2.
J Hazard Mater ; 415: 125625, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33740726

RESUMO

This study focused on classifying and disposing Circulating fluidized bed (CFB) fly ashes from the level of its origin, and proposed an optimal formulation system for clinker-free cemented backfill materials. CFB fly ash-blast furnace slag (BFS)-based cemented backfill materials with unequal strength grades are used in different locations of the goaf that require more than 1 Mpa and 4 Mpa, respectively, and the leaching levels of all toxic components are lower than the underground III water quality standard limit when the additional amount of CFB fly ash does not exceed 60 wt.%. The stable S/S of Cl- is due to the combined effect of chemical fixation of HCC and physical adsorption of the C-S-H/C-A-S-H phase. B2(20 wt.% CFB fly ash) exhibits more functional hydration products and higher degree of polymerization with the hydration age extension. Ettringite is the major effective product of CFB fly ash-BFS-based cemented system due to low level of chlorine environment and HCC transformation. CFB fly ash with appropriate active Al2O3 can dissolve and promote [AlO4]5- to substitute [SiO4]4- to form the C-A-S-H phase with longer chains and higher degree of polymerization with increase in Al/Si ratio of C-A-S-H/C-S-H phase.

3.
Analyst ; 146(6): 2019-2028, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33528468

RESUMO

Protein profiling of extracellular vesicles (EVs) provides important information in both clinical cancer diagnosis and relevant biological research studies. Although a variety of bioanalytical techniques have been investigated for EV characterization, limitations such as time-consuming operations, the requirement of large sample volume and demand for specialized instruments hinder their practical applications. Here, we report a simple and wash-free homogeneous colorimetric assay for sensitive detection of surface proteins on EVs. Au nanoparticles were modified with thiolated aptamers to fabricate aptasensors and incubated with EVs. Upon addition of a Au growth reagent, the solution color changed from light red to blue in the presence of target proteins and became deep red when the targets were absent. Expression of CD63, epithelial cell adhesion molecules (EpCAM), and mucin1 in EVs derived from two breast cancer cell lines (MCF-7 and MDA-MB-231) were compared, showing results consistent with western blotting results. The colorimetric assay achieves a limit of detection (LOD) down to 0.7 ng µL-1 against MCF-7 EVs based on the assessment of EpCAM expression, suggesting its potential to be applied in clinical breast cancer diagnosis.

4.
Arch Gynecol Obstet ; 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33555431

RESUMO

OBJECTIVE: To observe the levels of leukemia inhibitory factor (LIF), interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) in blood, peritoneal fluid, ectopic endometrial tissue, and ectopic endometrial stromal cells of patients with endometriosis, and to compare expression of IL-6, LIF and VEGF expression between endometriotic and non-endometriotic patients underwent laparoscopic surgery. METHODS: Thirty-one patients who underwent laparoscopic surgery for endometriosis in our hospital from January 2018 to January 2020 were included in the observation group, and 32 patients who underwent laparoscopic surgery for uterine fibroids, ovarian serous cystadenoma, and ovarian teratomas, were included in the control group. The levels of LIF, IL-6 and VEGF in the blood and peritoneal fluid of the two groups of patients were detected. The levels of LIF, IL-6 and VEGF in ectopic endometrial tissue and self-paired eutopic endometrial tissue, ectopic endometrial stromal cells and self-paired eutopic endometrial stromal cells of patients in the observation group were detected. After treating the primary cultured ectopic endometrial stromal cells with LIF and IL-6 alone or in combination, the changes of VEGF mRNA of ectopic endometrial stromal cells and the VEGF levels in the supernatant were observed. RESULTS: The levels of LIF, IL-6 and VEGF in the blood and peritoneal fluid of the observation group were all higher than those of the control group (P < 0.05), and the levels of LIF, IL-6 and VEGF in the peritoneal fluid of the observation group were significantly higher than those in the blood (P < 0.05). In the observation group, the expression levels of LIF-mRNA and IL-6 mRNA in the ectopic endometrial tissue were higher than those in the self-paired eutopic endometrial tissues (P < 0.05), while the expression level of VEGF mRNA in the ectopic endometrial tissues was lower than that in the self-paired eutopic endometrial tissues (P < 0.05). Besides, the mRNA expression levels of LIF, IL-6 and VEGF in ectopic endometrial stromal cells of the observation group were all higher than those in the self-paired eutopic endometrial stromal cells (P < 0.05). After stimulating ectopic endometrial stromal cells with LIF, IL-6 and LIF + IL-6, respectively, the VEGF levels in the supernatant were all significantly higher than that in the blank control group (P < 0.05). CONCLUSION: The LIF, IL-6 and VEGF levels in blood and peritoneal fluid were increased in patients with endometriosis, and increased LIF and IL-6 in ectopic endometriosis stromal cells can play a synergistic role in increasing the VEGF levels, which may be involved in the occurrence and development of endometriosis.

5.
Cell Death Dis ; 12(1): 65, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431801

RESUMO

Legumain is required for maintenance of normal kidney homeostasis. However, its role in acute kidney injury (AKI) is still unclear. Here, we induced AKI by bilateral ischemia-reperfusion injury (IRI) of renal arteries or folic acid in lgmnWT and lgmnKO mice. We assessed serum creatinine, blood urea nitrogen, histological indexes of tubular injury, and expression of KIM-1 and NGAL. Inflammatory infiltration was evaluated by immunohistological staining of CD3 and F4/80, and expression of TNF-α, CCL-2, IL-33, and IL-1α. Ferroptosis was evaluated by Acsl4, Cox-2, reactive oxygen species (ROS) indexes H2DCFDA and DHE, MDA and glutathione peroxidase 4 (GPX4). We induced ferroptosis by hypoxia or erastin in primary mouse renal tubular epithelial cells (mRTECs). Cellular survival, Acsl4, Cox-2, LDH release, ROS, and MDA levels were measured. We analyzed the degradation of GPX4 through inhibition of proteasomes or autophagy. Lysosomal GPX4 was assessed to determine GPX4 degradation pathway. Immunoprecipitation (IP) was used to determine the interactions between legumain, GPX4, HSC70, and HSP90. For tentative treatment, RR-11a was administrated intraperitoneally to a mouse model of IRI-induced AKI. Our results showed that legumain deficiency attenuated acute tubular injury, inflammation, and ferroptosis in either IRI or folic acid-induced AKI model. Ferroptosis induced by hypoxia or erastin was dampened in lgmnKO mRTECs compared with lgmnWT control. Deficiency of legumain prevented chaperone-mediated autophagy of GPX4. Results of IP suggested interactions between legumain, HSC70, HSP90, and GPX4. Administration of RR-11a ameliorated ferroptosis and renal injury in the AKI model. Together, our data indicate that legumain promotes chaperone-mediated autophagy of GPX4 therefore facilitates tubular ferroptosis in AKI.

6.
Neuropeptides ; 86: 102125, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33486279

RESUMO

AIMS: Spinal cord injury (SCI) can cause a variety of cells apoptosis, neurodegeneration, and eventually permanent paralysis. This study aimed to examine whether transplanting human umbilical cord mesenchymal stem cells (hucMSCs) can promote locomotor function recovery, reduce apoptosis and inhibit demyelination in SCI models. MAIN METHODS: Rats were allocated into Sham group (spinal cord exposure only), SCI + PBS group (spinal cord impact plus phosphate-buffered saline (PBS) injections), SCI + hucMSCs group (spinal cord impact plus hucMSCs injections) groups. Behavioral tests, Basso-Beattie-Bresnahan locomotion scores (BBB scores), were carried out at 0, 3, 7, 14, 21, 28 days after SCI surgery. Hematoxylin-eosin staining observed spinal cord morphology. Nissl staining detected the number of nissl bodies. Myelin basic protein (MBP) and oligodendrocyte (CNPase) were examed by immunohistochemical staining. The apoptosis of oligodendrocyte and neurons were detected by immunofluorescence. RESULTS: The 28-day behavioral test showed that the BBB score of rats in the SCI + hucMSCs group increased significantly, comparing to the SCI + PBS group. The numbers of nissl bodies and myelin sheath in the damaged area of SCI + hucMSCs group were also significantly increased compared to the SCI + PBS group. HucMSCs transplanting decreased the expression of protein level of Caspase-3 and Bax and increased the Bcl-2, MBP and CNPase, rescued the apoptosis of neurons and the oligodendrocyte. CONCLUSION: These results showed that hucMSCs can improve motor function, tissue repairing and reducing apoptosis in SCI rats.

7.
Glob Health Action ; 14(1): 1875601, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33472568

RESUMO

Background: The COVID-19 pandemic shows variable dynamics in WHO Regions, with lowest disease burden in the Western-Pacific Region. While China has been able to rapidly eliminate transmission of SARS-CoV-2, Germany - as well as most of Europe and the Americas - is struggling with high numbers of cases and deaths. Objective: We analyse COVID-19 epidemiology and control strategies in China and in Germany, two countries which have chosen profoundly different approaches to deal with the epidemic. Methods: In this narrative review, we searched the literature from 1 December 2019, to 4 December 2020. Results: China and several neighbours (e.g. Australia, Japan, South Korea, New Zealand, Thailand) have achieved COVID-19 elimination or sustained low case numbers. This can be attributed to: (1) experience with previous coronavirus outbreaks; (2) classification of SARS-CoV-2 in the highest risk category and consequent early employment of aggressive control measures; (3) mandatory isolation of cases and contacts in institutions; (4) broad employment of modern contact tracking technology; (5) travel restrictions to prevent SARS-CoV-2 re-importation; (6) cohesive communities with varying levels of social control. Conclusions: Early implementation of intense and sustained control measures is key to achieving a near normal social and economic life.


Assuntos
/epidemiologia , Controle de Doenças Transmissíveis/organização & administração , Surtos de Doenças/prevenção & controle , China/epidemiologia , Alemanha/epidemiologia , Humanos , Pandemias/prevenção & controle
8.
Chem Biodivers ; 18(2): e2000639, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33427403

RESUMO

Fractionation of the ethanol extract of a marine fungus, Arthrinium sp., afforded a new pyridone alkaloid (arthpyrone L (1)), the structure with absolute configuration of which was established by comprehensive spectroscopic analyses. In vitro cell viability assays revealed that compound 1 showed antiproliferative effects toward human A549 (lung), MG63, U2OS (bone), MCF-7 and MDA-MB-231 (breast) cancer cells. MG63 cell lines were chosen for further biological evaluations and presented apoptosis and cell cycle arrest (G0/G1 phase) upon treatment of 1. Subsequent mechanism studies demonstrated that the growth inhibition of 1 against MG63 cells was via activation of caspase-modulated apoptotic pathway and inhibition of PI3K/Akt pathway.

9.
Plant Physiol Biochem ; 159: 226-233, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33387851

RESUMO

Plants can reduce or eliminate the damage caused by herbicides and gain herbicide resistance, which is an important theoretical basis for the development of herbicide-resistant crops at this stage. Thus, discovering novel herbicide-resistant genes to produce diverse herbicide-resistant crop species is of great value. The glycosyltransferases that commonly exist in plant kingdom modify the receptor molecules to change their physical characteristics and biological activities, and thus possess an important potential to be used in the herbicide-resistance breeding. Here, we identified a novel herbicide-induced UDP-glycosyltransferase 91C1 (UGT91C1) from Arabidopsis thaliana and demonstrated its glucosylating activity toward sulcotrione, a kind of triketone herbicides widely used in the world. Overexpression of UGT91C1 gene enhanced the Arabidopsis tolerance to sulcotrione. While, ugt91c1 mutant displayed serious damage and reduced chlorophyll contents in the presence of sulcotrione, suggesting an important role of UGT91C1 in herbicide detoxification through glycosylation. Moreover, it was also noted that UGT91C1 can affect tyrosine metabolism by reducing the sulcotrione toxicity. Together, our identification of glycosyltransferase UGT91C1, as a potential gene conferring herbicide detoxification through glucosylation, may open up a new possibility for herbicide resistant breeding of crop plants and environmental phytoremediation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis , Glicosiltransferases/metabolismo , Resistência a Herbicidas , Inativação Metabólica , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Glicosiltransferases/genética , Resistência a Herbicidas/genética , Herbicidas/metabolismo , Herbicidas/toxicidade , Inativação Metabólica/genética
10.
Food Funct ; 12(4): 1626-1638, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33476357

RESUMO

Clam is a kind of nutritious, delicious and economical aquatic food around the world and is famous for its unique aroma. Instrumental analysis, sensory analysis, and comprehensive statistical analysis were performed to explain the relationship between aroma and odorants in clam soup. Six extraction methods combined with GC-MS and sniffing were utilized to obtain the aroma fingerprints of clam soup and to analyze the correlation with aroma perception. Solvent extraction methods were more effective than headspace extraction methods for the volatiles of clam soup. SAFE was the best method to obtain the most comprehensive information of volatiles of clam soup. The sequence of a combination of different extraction methods and SAFE would also affect the results of volatiles extracted from clam soup. Volatiles extracted via SDE, P&T, and SPME would add further information to the result of SAFE. A total of 119 volatile compounds were identified from clam soup by summarising the results of different extraction methods. The significant effect of 14 key odorants in clam soup on aroma perception was verified by aroma recombination and odorant omission tests. A neural network diagram of the aroma profile was designed to visualize the information of odor perception. Furthermore, the results would be beneficial for aroma research studies of aquatic food and the processing of clam products.

11.
Mol Med Rep ; 23(1): 1, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33236154

RESUMO

Inonotus obliquus (IO) is an edible fungus that exerts various biological functions, including anti­inflammatory, antitumor and immunomodulatory effects. The present study was designed to investigate the role of IO extract (IOE) in myocardial ischemia/reperfusion (MI/R) and determine the exact molecular mechanisms. The left anterior descending coronary artery was ligated to establish the MI/R injury model in rats. IOE exhibited a novel cardioprotective effect, as shown by improvement in cardiac function and decrease in infarct size. Pretreatment with IOE activated antioxidant enzymes in cardiomyocytes, including glutathione peroxidase, superoxide dismutase and catalase. IOE pretreatment also induced the upregulation of NAD­dependent protein deacetylase sirtuin­1 (SIRT1) and downregulation of glucose­regulated protein 78, phosphorylated (p­) protein kinase R­like endoplasmic reticulum kinase, p­eukaryotic translation initiation factor 2 subunit α, C/EBP homologous protein and caspase­12. Furthermore, IOE alleviated endoplasmic reticulum (ER) stress­induced apoptosis in cardiomyocytes by decreasing the mRNA levels of caspase­12. IOE inhibited apoptosis induced by overexpression of pro­caspase­9 and pro­caspase­3. In summary, IOE pretreatment protects the heart against MI/R injury through attenuating oxidative damage and suppressing ER stress­induced apoptosis, which may be primarily due to SIRT1 activation.

12.
Mol Neurobiol ; 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33219900

RESUMO

Neuroinflammation is the important pathological feature of Alzheimer's disease (AD). Legumain, a lysosomal cysteine protease, plays an important role in neuroinflammation during ischemic stroke and depressive disorder. Legumain is involved in AD process through cleaving APP; however, it is unclear if legumain can possibly modulate neuroinflammation without cleaving APP in AD. Thus, we established a mouse model of AD by single intracerebroventricular injections of Aß1-42 in legumain knockout (KO) mice. The behavioral tests showed that legumain-KO effectively ameliorated cognitive impairment induced by Aß1-42. Moreover, legumain deprivation significantly improves the synaptic plasticity damages in Aß1-42-treated mice. Moreover, legumain-KO considerably inhibited the activation of microglia and reduced the expression of inflammatory cytokines in the hippocampus of Aß1-42-treated mice. Interestingly, we found that legumain-KO inhibited TLR4/MyD88/NF-κB pathway, which was activated by Aß1-42 in the hippocampus. In conclusion, our results suggested that legumain-KO reduced the level of neuroinflammation that was associated with inhibiting TLR4/MyD88/NF-κB pathways, thereby improving the hippocampal synaptic plasticity and reducing the cognitive impairments in Aß1-42-treated mice. Legumain knockout blocked microglia activation by inhibiting TLR4/MyD88/NF-κB signaling pathways, and further reduced inflammatory cytokine expression. As a result, legumain knockout alleviated synaptic damage and cognitive impairment induced by Aß1--42.

13.
Environ Pollut ; : 115558, 2020 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-33223337

RESUMO

Rural residential coal combustion (RRCC) has detrimental effects on air quality, climate, and human health. There are large uncertainties regarding emissions from RRCC owing to the lack of consideration of several key factors (e.g. combination modes of coal and stoves, combustion modes, and high temporal resolution). In this study, we provided a new estimation framework for RRCC emissions through a case study in the Beijing-Tianjin-Hebei (BTH) region, China. The emission estimations were improved according to four aspects, namely (1) coal-specific and stove-specific coal consumption was calculated based on face-to-face field interviews of 6700 valid volunteers/households covering 288 villages in 50 counties; (2) the influences of combustion modes (flaming and smoldering modes) on emissions were considered; (3) emissions of different fuel-stove combinations were estimated based on coal, stove, and combustion mode-specific RRCC consumption and localised emission factors; and (4) a method for emission estimation with high temporal resolution (1 h) was developed. The results indicated that RRCC emitted 413.6 kt SO2, 55.7 kt NOx, 5717.3 kt CO, 149.4 kt VOCs, 167.1 kt PM2.5, 18.2 kt EC, 32.5 kt OC, and 8.2 kt NH3 in 2016. The combination of bituminous coal and an advanced coal stove was the most significant contributor (20.7-71.8%) to various pollutant emissions. Coal combusted under the flaming mode contributed to most (81.9%) of the total coal consumption, and thus emitted the majority (50.8-99.8%) of pollutants, except for VOCs. Meanwhile, that under the smoldering mode only accounted for 18.1% of the total consumption, but contributed 49.2% and 74.7% of the CO and VOCs emissions, respectively. Two clear emission peaks occurred at approximately 7:00-9:00 and 18:00-20:00. The detailed coal consumption and emissions with high temporal and spatial resolution can provide sound data for further research on rural environmental issues and scientific support to pollution control strategies.

14.
J Hazard Mater ; : 124404, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33153794

RESUMO

Landfill disposal of municipal solid waste incineration fly ash (MIFA) presents significant environmental and economic burden. This study proposed a novel and high-efficiency approach for stabilisation/solidification (S/S) of MIFA by phosphate-modified calcium aluminate cement (CAC). Experimental results showed that the presence of Pb (the most leachable metal contaminant in the MIFA) retarded the early-stage reaction of CAC, resulting in an extension of setting time and a significant decline of compressive strength of CAC pastes. The incorporation of phosphate additives (10 wt% of binder), especially for trisodium phosphate, in CAC system effectively mitigated the negative impact of Pb on the CAC reaction and reduced the Pb leachability. Elemental mapping results illustrated that Pb2+ coordinated with phosphate to generate insoluble precipitates (e.g., Pb3(PO4)2). The S/S treated MIFA samples fulfilled the compressive strength and leachability requirements for on-site reuse. Overall, this study demonstrated that phosphate-modified CAC is a promising binder for S/S of hazardous MIFA.

15.
Bone Joint Res ; 9(10): 675-688, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33101657

RESUMO

Aims: Parathyroid hormone (PTH) (1-34) exhibits potential in preventing degeneration in both cartilage and subchondral bone in osteoarthritis (OA) development. We assessed the effects of PTH (1-34) at different concentrations on bone and cartilage metabolism in a collagenase-induced mouse model of OA and examined whether PTH (1-34) affects the JAK2/STAT3 signalling pathway in this process. Methods: Collagenase-induced OA was established in C57Bl/6 mice. Therapy with PTH (1-34) (10 µg/kg/day or 40 µg/kg/day) was initiated immediately after surgery and continued for six weeks. Cartilage pathology was evaluated by gross visual, histology, and immunohistochemical assessments. Cell apoptosis was analyzed by TUNEL staining. Microcomputed tomography (micro-CT) was used to evaluate the bone mass and the microarchitecture in subchondral bone. Results: Enhanced matrix catabolism, increased apoptosis of chondrocytes in cartilage, and overexpressed JAK2/STAT3 and p-JAK2/p-STAT3 were observed in cartilage in this model. All of these changes were prevented by PTH (1-34) treatment, with no significant difference between the low-dose and high-dose groups. Micro-CT analysis indicated that bone mineral density (BMD), bone volume/trabecular volume (BV/TV), and trabecular thickness (Tb.Th) levels were significantly lower in the OA group than those in the Sham, PTH 10 µg, and PTH 40 µg groups, but these parameters were significantly higher in the PTH 40 µg group than in the PTH 10 µg group. Conclusion: Intermittent administration of PTH (1-34) exhibits protective effects on both cartilage and subchondral bone in a dose-dependent manner on the latter in a collagenase-induced OA mouse model, which may be involved in regulating the JAK2/STAT3 signalling pathway.Cite this article: Bone Joint Res 2020;9(10):675-688.

16.
Chem Commun (Camb) ; 56(84): 12833-12836, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-32966390

RESUMO

We report two ligand-protected Au4Ru2 and Au5Ru2 nanoclusters with distinct atomic-packing modes and electronic structures, both of which act as ideal model catalysts for identifying the catalytically active sites of catalysts on the nanoclusters. Au5Ru2 exhibits superior catalytic performances to Au4Ru2 for N-methylation of N-methylaniline to N-methylformanili, which is likely due to the site-cooperation catalysis of Au5Ru2.

17.
Nanoscale ; 12(35): 18004-18012, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32870213

RESUMO

Atomically precise gold nanoclusters protected by ligands are being intensely investigated in current catalysis science, due to the definitive correlation between the catalytic properties and structures at an atomic level. By solving the crystal structures of the nanoclusters, coupled with in situ and ex situ spectroscopy, a very fundamental understanding can be achieved to learn what controls the catalytic activation, active site structure, and catalytic mechanism. Herein, we mainly focus on the recent progress in catalysis controlled by precisely modulating the surface structures of the nanoclusters, including the alteration of the surface motifs, the doping of heterogeneous atoms in the surface of the nanoclusters, and the surface ligand engineering. The article is expected to help not only gain deep insight into the crucial roles of surface motifs of the nanoclusters in regulating the catalytic properties, but also explore the wide catalytic applications of atomically precise nanoclusters by elaborately tailoring the surface of the nanoclusters.

18.
Biochem Biophys Res Commun ; 532(1): 1-10, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-32826059

RESUMO

The anther is one of the most vulnerable organs to temperature stress. Many previous works focused on the genes regulating anthers development, but few results of miRNA in anther development were reported. In order to investigate the transcriptional regulation of temperature-sensitive anther development, RNA-Sequencing was used to study micRNA in anthers of Arabidopsis thaliana under 16 °C and 27 °C. A total of 46.26 million clean reads were generated and mapped to 715,748 small RNA sequences containing 281 miRNAs. Then 13 differentially expressed (DE) miRNAs, containing 3 novel miRNAs were found. Comprehensive analysis of miRNA expression showed 7 miRNAs were down-regulated and 6 miRNAs were up-regulated. Furthermore, 13 DE miRNAs putatively regulated 614 DE mRNAs. Among them, 20 important anther genes were predicted as target genes of MIR319A, MIR447A, MIR447B and MIR398B, respectively. Over-expression MIR319A and MIR447A could effectively inhibit the transcription of target genes and lead to male sterile. It suggested that DE miRNAs might mediate temperature signals and regulate anther and pollen development. Our work will provide a broader idea and valuable data information for further understanding the mechanism of thermo-sensitive male fertility in plants.

19.
Nanoscale ; 12(33): 17530-17537, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32812597

RESUMO

Recent advances in manipulating plasmonic properties of metal/semiconductor heterostructures have opened up new avenues for basic research and applications. Herein, we present a versatile strategy for the assembly of arrays of plasmonic metal/semiconductor hemispherical nano-heterostructures (MSHNs) with control over spacing and size of the metal/semiconductor heterostructure array, which can facilitate a wide range of scientific studies and applications. The strategy combines nanosphere lithography for generating the metal core array with solution-based chemical methods for the semiconductor shell that are widely available and kinetically controllable. Periodic arrays of Au/Cu2O and Ag/Cu2O heterostructures are synthesized to demonstrate the approach and highlight the versatility and importance of the tunability of plasmonic properties. The morphology, structure, optical properties, and elemental compositions of the heterostructures were analyzed. This strategy can be important for understanding and manipulating fundamental nanoscale solid-state physical and chemical properties, as well as assembling heterostructures with desirable structure and functionality for applications.

20.
Carbohydr Polym ; 246: 116645, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32747278

RESUMO

Alginate is a commercially important polysaccharide widely applied in various industries. Carbohydrate-binding proteins could be utilized as desirable tools in the investigation and further applications of polysaccharides. Few alginate-binding proteins have hitherto been characterized and reported. In the present study, a novel alginate-binding protein ABP_Wf, consisting of two "orphan" carbohydrate-binding modules, was cloned from a predicted alginate utilization locus of marine bacterium Wenyingzhuangia funcanilytica, and expressed in Escherichia coli. ABP_Wf exhibited a specific binding capacity to alginate, and the association constant (Ka) and affinity (KD) were 1.94 × 103 M-1s-1 and 1.16 × 10-6 M. It was confirmed that the binding capacity of ABP_Wf to alginate is attributed to its constituent CBM16 domain rather than the CBM44 domain. The potentials of ABP_Wf in the semi-quantitative detection and the in situ visualization of alginate were evaluated, which implied that ABP_Wf could be served as a promising tool for investigating alginate.

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