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1.
J Hazard Mater ; 383: 121149, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31550667

RESUMO

Water pollution and energy crisis are two important research subjects awaited to solution. Herein, we propose a strategy of "turning scrap into wealth" to obtain the highly-efficient photocatalyst for hydrogen evolution by recycling of heavy metal ions in wastewater. The novel mesoporous zeolite Beta (mBeta) can be used as adsorbent to remove the heavy metal ions (i.e., Cd2+ and/or Zn2+) from wastewater due to its excellent adsorptive performance from the electrostatic affinity, ion-exchange ability and structural channels in zeolite. Subsequently, in-situ sulfuring of the Cd2+ or/and Zn2+ adsorbed mBeta was carried out to obtain highly-efficient photocatalysts. As expected, the sample CdS/ZnS-mBeta exhibited super photocatalytic activity and high stability under visible light irradiation. It is believed that the synergetic effect between CdS and ZnS nanoparticles are responsible for its good visible light absorption performance and the effective separation of photoelectrons and holes. Besides, the mBeta with high specific surface area can improve the dispersibility of sulfides, which would contribute to its high stability.

2.
J Cell Physiol ; 235(1): 221-231, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31187497

RESUMO

The motility of mesenchymal stem cells (MSCs) is highly related to their homing in vivo, a critical issue in regenerative medicine. Our previous study indicated copper (Cu) might promote the recruitment of endogenous MSCs in canine esophagus defect model. In this study, we investigated the effect of Cu on the motility of bone marrow mesenchymal stem cells (BMSCs) and the underlying mechanism in vitro. Cu supplementation could enhance the motility of BMSCs, and upregulate the expression of hypoxia-inducible factor 1α (Hif1α) at the protein level, and upregulate the expression of rho family GTPase 3 (Rnd3) at messenger RNA and protein level. When Hif1α was silenced by small interfering RNA (siRNA), Cu-induced Rnd3 upregulation was blocked. When Rnd3 was silenced by siRNA, the motility of BMSCs was decreased with or without Cu supplementation, and Cu-induced cytoskeleton remodeling was neutralized. Furthermore, overexpression of Rnd3 also increased the motility of BMSCs and induced cytoskeleton remodeling. Overall, our results demonstrated that Cu enhanced BMSCs migration through, at least in part, cytoskeleton remodeling via Hif1α-dependent upregulation of Rnd3. This study provided an insight into the mechanism of the effect of Cu on the motility of BMSCs, and a theoretical foundation of applying Cu to improve the recruitment of BMSCs in tissue engineering and cytotherapy.

3.
Plant Sci ; 290: 110267, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31779911

RESUMO

Both nitrogen (N) and potassium (K) have been widely studied in maintaining efficient photosynthesis and plant growth. However, the mechanisms underlying the photosynthetic response to their interaction remain unclear. This study assessed the effects of N and K supply on photosynthetic limitations and the corresponding changes in anatomical structures in leaves of rice (Oryza sativa L.) plants, grown hydroponically under different levels of N and K in a greenhouse. Results revealed that a suitable leaf N/K ratio (2.99-3.10) maintain a high rate of photosynthesis (A). The A under N and/or K deficiency was primarily limited by mesophyll conductance (gm) and RuBP carboxylation in biochemical processes. The decline of gm in N- or K-starved leaves was mostly resulted from low surface area of chloroplasts exposed to intercellular airspaces (Sc) and high mesophyll cell wall thickness. Synergistic effects of N and K on gm were reflected in leaf anatomical structure, especially their coordinated roles in enhancing Sc. The enhanced photosynthesis in plants with coordinated supply of N and K was caused by the balance of RuBP carboxylation and regeneration. These results highlight the synergistic effect of N and K on leaf photosynthesis, which are mainly reflected in facilitating anatomical-determined gm and carboxylation capacity.

4.
Mater Sci Eng C Mater Biol Appl ; 106: 110153, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753368

RESUMO

Three dimensional (3D) printed porous bioactive glass nanoparticles scaffolds (BGNS) exhibit excellent bone integration and bone regeneration capacities, but the early rapid ion release, brittle mechanical properties and lack of functions limit their application. In this work, photoluminescent biomimetic elastomeric BGNS were fabricated by directly assembling poly(citrate-siloxane) (PCS) on the surface of BGNS (BGNS@PCS). The morphologies, mechanical behavior, photoluminescent ability, ions release, biomineralization activity, biocompatibility and osteogenic properties of BGNS@PCS were evaluated in detail. The results indicated that BGNS@PCS presented superior elasticity and outstanding compressive strength compared with BGNS. The controlled release of the Si and Ca ions in BGNS@PCS was achieved and enhanced biomineralization ability was also observed. In addition, the modified scaffolds have the photoluminescent ability which has the potential application for bioimaging. BGNS@PCS could significantly promote cells attachment, proliferation and enhance osteogenic differentiation of mouse bone marrow stromal cells (BMSCs). Therefore, the BGNS@PCS with the multifunctional properties including elastomeric surface, enhanced photoluminescent, controlled ions release and biomineralization, reinforced osteogenic activity, would be a promising candidate for bone tissue regeneration. This study probably provides a novel strategy to design biomimetic elastomeric bioceramic scaffolds for hard tissue regeneration.

5.
Biomed Pharmacother ; 121: 109565, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31704615

RESUMO

With the improvement of people's living standard and the changes of environment, the incidence of diabetes mellitus (DM) is on the rise day by day, while clinical treatment mainly aims at lowering blood glucose, instead of fundamental prevention and treatment. What's worse, the measures of prevention and treatment of DM complications remain inadequate. Both Chinese and modern medicine have advantages and disadvantages in treating DM, therefore, it would be a worthy attempt to break through the bottleneck of DM treatment by combining the advantages of both, and explore the new measures to prevent and deal with DM from the perspective of the combination of Traditional Chinese Medicine (TCM) syndrome and modern medicine. In this paper, modern research methods and possible indicators of TCM syndromes of DM were expounded from clinical and basic research aspects, aiming to find specific biomarkers of TCM syndromes, and providing experimental supports for the diagnosis and treatment of DM and the verification of TCM theory.

6.
J Cell Biochem ; 121(1): 596-608, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31407404

RESUMO

Cervical cancer is the third leading cause of female death in the world. Serum microRNAs (miRNAs) are currently considered to be valuable as noninvasive cancer biomarkers, but their role in the prognosis of cervical cancer has not been elucidated. We aimed to find serum miRNAs that can be used as prognostic factors for cervical cancer. A traumatic pathological biopsy is the only reliable method for determining the severity of cervical cancer currently. Thus, noninvasive diagnostic markers are needed. The serological expression of candidate miRNAs were measured in 90 participants, including 60 patients with cervical cancer and 50 patients with cervical intraepithelial neoplasia. Two patients with cervical cancer were excluded from the study because of lack of data. miRNAs were evaluated by quantitative reverse transcription polymerase chain reaction. miR-143/-4636 appeared specific for cervical cancer compared with cervical intraepithelial neoplasia (P < .001). The classification performance of validated miRNAs for cervical cancer [Area under the receiver operating characteristic curve (AUC) = 0.942] was better than that reached by squamous cell carcinoma antigen (SCC-Ag; AUC = 0.727). Poor-differentiation group has lower miR-143/-4636 levels in serum (P < .05). miR-4636 level was correlated gross tumor volume and the depth of invasion (P < .0001). In our study, we found a combination of miR-143 and miR-4636 that is independently and strongly associated with cervical cancer prognosis and can be used as a clinically prognostic factor.

7.
Appl Radiat Isot ; 155: 108915, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31590101

RESUMO

To develop PET radiotracers for imaging of Alzheimer's disease, a new carbon-11 labeled potent and selective γ-secretase modulator (GSM) has been synthesized. The reference standard tetrahydrobenzisoxazole derivative 8 and its desmethylated precursor 9 were synthesized from cyclohex-2-en-1-one and 3-hydroxy-4-nitrobenzaldehyde in eight and nine steps with 11% and 5% overall chemical yield, respectively. The radiotracer [11C]8 was prepared from its corresponding precursor 9 with [11C]CH3OTf through O-11C-methylation and isolated by RP-HPLC combined with SPE in 45-50% radiochemical yield, based on [11C]CO2 and decay corrected to EOB. The radiochemical purity was >99%, and the molar activity (Am) at EOB was 555-740 GBq/µmol.

8.
Sci China Life Sci ; 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31792780

RESUMO

Cas1 is a key component of the CRISPR adaptation complex, which captures and integrates foreign DNA into the CRISPR array, resulting in the generation of new spacers. We have determined crystal structures of Thermus thermophilus Cas1 involved in new spacer acquisition both in complex with branched DNA and in the free state. Cas1 forms an asymmetric dimer without DNA. Conversely, two asymmetrical dimers bound to two branched DNAs result in the formation of a DNA-mediated tetramer, dimer of structurally asymmetrical dimers, in which the two subunits markedly present different conformations. In the DNA binding complex, the N-terminal domain adopts different orientations with respect to the C-terminal domain in the two monomers that form the dimer. Substrate binding triggers a conformational change in the loop 164-177 segment. This loop is also involved in the 3' fork arm and 5' fork arm strand recognition in monomer A and B, respectively. This study provides important insights into the molecular mechanism of new spacer adaptation.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31790725

RESUMO

Although higher precuneus activation has often been observed in subjects with addictions when facing addiction-relevant cues, the recruitment of the precuneus is not consistent across studies. Here, we examined the extent to which addiction severity may relate to precuneus involvement during cue reactivity in internet gaming disorder (IGD). We recruited 65 subjects with IGD, collected brain responses when exposed to gaming cues and assessed brain structure. We correlated IGD severity with brain responses during a cue-craving task, precuneus volume, and connectivity with respect to inputs/outputs to/from the precuneus. In the cue-craving task, IGD severity was positively correlated with precuneus activation when exposed to gaming cues. IGD severity was also positively correlated with the volume of precuneus and connectivity from the hippocampal gyrus to the precuneus. IGD severity was also negatively correlated with connectivity from the middle frontal gyrus to the precuneus. In IGD, IGD severity relates to precuneus involvement with respect to functionality, morphology, and connectivity. The precuneus may act as a platform for integrating potential contradictory information between executive control and sub-cortical cravings.

11.
Adv Healthc Mater ; : e1900635, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31788987

RESUMO

Microneedles (MNs) permit the delivery of nucleic acids like small interfering RNA (siRNA) through the stratum corneum and subsequently into the skin tissue. However, skin penetration is only the first step in successful implementation of siRNA therapy. These delivered siRNAs need to be resistant to enzymatic degradation, enter target cells, and escape the endosome-lysosome degradation axis. To address this challenge, this article introduces a nanoparticle-embedding MN system that contains a dissolvable hyaluronic acid (HA) matrix and mesoporous silica-coated upconversion nanoparticles (UCNPs@mSiO2 ). The mesoporous silica (mSiO2 ) shell is used to load and protect siRNA while the upconversion nanoparticle (UCNP) core allows the tracking of MN skin penetration and NP diffusion through upconversion luminescence imaging or optical coherence tomography (OCT) imaging. Once inserted into the skin, the HA matrix dissolves and UCNPs@mSiO2 diffuse in the skin tissue before entering the cells for delivering the loaded genes. As a proof of concept, this system is used to deliver molecular beacons (MBs) and siRNA targeting transforming growth factor-beta type I receptor (TGF-ßRI) that is potentially used for abnormal scar treatment.

12.
Nutr J ; 18(1): 80, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31785608

RESUMO

BACKGROUND: Acute respiratory infections (ARI), including the common cold causes significant morbidity and economical losses globally. Micronutrient deficiency may increase ARI incidence risk and its associated duration and severity among healthy adults, but evidence are inconclusive. This study aims to systematically review all observations on the association between single micronutrient deficiency and ARI incidence, duration and severity in healthy adults. METHODS: Systematic literature searches were conducted in PubMed, Cochrane Library, Embase and Scopus databases. Eligible studies were assessed for the reporting and methodological quality. Adjusted summary statistics with their relevant 95% confidence intervals or interquartile ranges were extracted for the outcomes of interest. RESULTS: The literature search identified 423 unique studies. Of which, only eight studies were eligible and included in the final review. Only vitamin D deficiency (VDD) was observed among these eight studies. There were no eligible studies that focused on the association between other single micronutrient deficiency and ARI. The review found mixed observations on ARI incidence, and a lack of evidence on its associated severity to conclude the association between VDD and these outcomes. However, existing evidence consistently suggested that VDD is likely to lead to longer ARI duration (median duration in days: deficient group, 4 to 13; non-deficient groups, 2 to 8). CONCLUSION: This review found that VDD may be associated to longer ARI duration, but its effect on ARI incidence and its associated severity among healthy adults remains inconclusive. This review also highlighted the lack of a consistent regional and/or global definition for micronutrient sufficiency, and that future studies should explore and conclude the association between other micronutrient deficiency and ARIs in healthy adults before considering supplementation for ARI prevention and management.

13.
PLoS One ; 14(12): e0225750, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800596

RESUMO

Natural Cordyceps sinensis, which is a valuable anti-tumor, immunomodulatory, and antiviral agent in Asia, has been overexploited in recent years. Therefore, it is important for cultivated C. sinensis to be recognized in the market. In this research, the main components of entirely cultivated, naturally grown C. sinensis, and stiff worms across different sampling years were detected and compared by HPLC-MS and UV spectrometry. The results indicated that the mean levels of adenosine and cordycepin were significantly higher, whereas the mean levels of mannitol and polysaccharides were remarkably lower in the cultivated type than in the natural type. No distinct difference in the average soluble protein content was observed. The composition of the stiff worms was similar to that of the natural herb, except that the total soluble protein content was higher, and that of mannitol was lower. In addition, the ultraviolet absorption spectroscopy of the three types showed high similarity at 260 nm. This research indicates that the main nutritional composition of cultivated and natural C. sinensis is identical and that cultivated type can be used as an effective substitute.

14.
Cell Rep ; 29(10): 3101-3117.e7, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31801076

RESUMO

Although adult neurogenesis recapitulates processes that occur during embryonic development, it exhibits distinct characteristics from the embryonic counterpart. However, the intrinsic mechanism underlying the differential regulation of neurogenesis between these two stages remains unclear. Herein, we show that the ablation of RNA-binding protein HuR in NSCs impairs adult but not embryonic neurogenesis. HuR is predominantly expressed in the cytoplasm of embryonic NSCs but translocates into the nucleus of adult NSCs. Transcriptomic analysis of HuR-deficient adult NSCs revealed that HuR primarily regulates alternative splicing of numerous premRNA transcripts, including focal adhesion kinase (FAK). HuR-deficient adult NSCs generate increased FAK mRNA isoforms with shorter 5'-UTRs, leading to enhanced FAK mRNA translation and hyperactivated FAK signaling, and inhibition of FAK ameliorates defective adult neurogenesis and impaired hippocampus-dependent learning in HuR-deficient mice. These findings provide mechanistic insights into the differential regulation of embryonic and adult neurogenesis through developmental cytoplasmic-to-nuclear translocation of HuR.

15.
Biosci Rep ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31803920

RESUMO

BACKGROUND: MicroRNA-135(miR-135) is a well-known non-coding RNA that has been demonstrated to participate in tumorigenesis and cancer development; however, the clinical prognostic value of microRNA-135 in digestive system cancers remains controversial. This meta-analysis aims to explore the potential value of microRNA-135 as a prognostic marker for digestive system cancers. METHODS: The PubMed, Embase, Cochrane Library, and Web of Science databases were searched for eligible articles published before August 31, 2019. Stata 12.0 software was used to analyze the overall survival (OS), disease-free survival (DFS), and recurrence-free survival (RFS) rates to access the prognostic value of microRNA-135 in digestive system cancers. We then used TCGA datasets to validate the meta-analysis results. Results A total of 1,470 patients from 17 studies were included in this meta-analysis. The pooled results showed that enhanced microRNA-135 expression was significantly associated with poor OR (HR: 1.790; 95%CI: 1.577-2.031; P=0.000), DFS (HR: 1.482; 95%CI: 0.914-2.403; P=0.110), and RFS (HR: 3.994; 95%CI: 1.363-11.697; P=0.012) in digestive system cancers. A sensitivity analysis confirmed the reliability of our findings, and no significant publication bias was observed. CONCLUSION: MicroRNA-135 can be used as a novel biomarker for patients with digestive system cancers. We look forward to future large-scale clinical studies that will investigate the prognostic value of microRNA-135.

16.
J Environ Pathol Toxicol Oncol ; 38(3): 271-283, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679313

RESUMO

Certain mechanical stimuli-particularly low-magnitude, high-frequency vibration-could induce bone marrow stem cell osteogenic differentiation and promote bone formation via Wnt signaling pathway, although the molecular mechanism is still unclear. In this study, we found that miR-335-5p is significantly upregulated after low-magnitude, high-frequency vibration, which suppresses the expression of the Wnt signaling inhibitor Dickkopf-related protein 1. Inhibition of miR-335-5p greatly reduced the osteogenic differentiation. Furthermore, the increase of miR-335-5p level was also confirmed in vivo after LMHF vibration in rabbit. Our study elucidates the prominent role of miRNAs that links the LMHF vibration and osteogenic differentiation.


Assuntos
Expressão Gênica , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Osteogênese/fisiologia , Vibração/efeitos adversos , Animais , Diferenciação Celular/fisiologia , Masculino , MicroRNAs/metabolismo , Coelhos
17.
Sci Rep ; 9(1): 15744, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31673091

RESUMO

Endoscopic grading of gastroesophageal flap valve (GEFV) is simple and reproducible and offers useful information for reflux activity. To investigate the potential correlation between GEFV grading and reflux finding score (RFS) in patients with laryngopharyngeal reflux disease (LPRD), 225 consecutive Patients with suspected LPRD who underwent both routine upper gastrointestinal endoscopy and laryngoscope were enrolled in our study. Patients with a RFS of more than 7 were diagnosed with LPRD. The GEFV was graded as I through IV according to Hill's classification and was classified into two groups: normal GEFV group (grades I and II) and the abnormal GEFV group (grades III and IV). The percent of GEFV grades I to IV was 39.1%, 39.1%, 12.4%, and 9.3%, respectively. Age was significantly related to an abnormal GEFV (p = 0.002). Gender, BMI, smoke and alcohol were not related to GEFV grade. Fifty-one patients (22.67%) had positive RFS. Reflux finding scores were higher in GEFV grades III and IV than I and II (p < 0.05). Endoscopic grading of GEFV is well correlated with reflux finding score in patients with LPRD. This is a simple and useful technique that provides valuable diagnostic information of LPRD.

18.
Artigo em Inglês | MEDLINE | ID: mdl-31675344

RESUMO

To solve the disturbed time-varying inversion problem, an exponential-type anti-noise varying-gain network (EAVGN) is proposed and analyzed. To do so, a vector-based error function is first defined. By using the varying-gain neural dynamic design method, an EAVGN model is then formulated. Furthermore, the differentiation error and the model-implementation error are considered into the model, and the perturbed EAVGN model is obtained. For better illustrations, comparisons between the EAVGN and the conventional fixed-parameter recurrent neural network (FP-RNN) are conducted to illustrate the advantages of the proposed EAVGN. Mathematical proof demonstrates that the proposed EAVGN has much better anti-noise properties than FP-RNN. On one hand, the residual error of EAVGN can be reduced to zero in any case, but that of FP-RNN is large and cannot be convergent, in particular when the bound of Frobenius norm of the exact solution is large or the noise is large. On the other hand, the bound of the residual error of EAVGN is always smaller than that of FP-RNN. Simulation results verify that when different types of noises exist, the proposed EAVGN owns better anti-noise property compared with the state-of-the-art methods. In addition, a practical application is presented to illustrate the implementation process and the practical benefits of the EAVGN.

19.
Zootaxa ; 4590(5): zootaxa.4590.5.7, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31716078

RESUMO

Two new species of the genus Hamodes Guenée, 1852, H. pseudobutleri sp. nov. and H. hainana sp. nov. are described from Southern China. Compared with the already known species H. butleri, the new species have a wider submarginal line on forewing and medial line on hindwing respectively; and in male genitalia, H. pseudobutleri sp. nov. has a shorter and curved saccular process, while H. hainana sp. nov. has a stouter saccular process. In addition, H. pendleburyi Prout, 1932 is recorded in mainland China for the first time. Adults and their genitalia are illustrated.


Assuntos
Lepidópteros , Mariposas , Animais , China , Genitália , Masculino
20.
Zootaxa ; 4590(3): zootaxa.4590.3.5, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31716089

RESUMO

Pangrapta Hübner, 1818 was erected for the North American species P. decoralis Hübner, 1818 as its type species. The genus Pangrapta presently consists of about 100 species, and is widely distributed in China and surrounding regions, as well as in the New World (Hu Wang, 2013). In this article, three new species, P. nanlingensis sp. n., P. jianfenglingensis sp. n. and P. hainanensis sp. n., are described from China. Each of them is superficially similar to the species, P. neorecusata (Hu Wang, 2013), P. perturbans (Walker, 1858) and P. pannosoides (Holloway, 2005), correspondently. The known Southeast Asian species, P. shivula (Guenée, 1852), is reported for the first time from China. Adults and genitalia are illustrated. The type series of all described species (including holotypes) are deposited in Southwest University of Science and Technology (SWUST), Mianyang, China.


Assuntos
Lepidópteros , Mariposas , Animais , China , Genitália
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