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1.
Methods Mol Biol ; 2133: 119-140, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32144665

RESUMO

The chemical synthesis of proteins allows for the precise control of structural information at the atomic level, overcoming the limits of protein expression. Peptide hydrazides are widely used as thioester equivalents in the total chemical synthesis and semisynthesis of proteins as they can be easily prepared using standard solid phase peptide synthesis (SPPS) and recombinant peptide techniques. Via treatment with NaNO2 and subsequent thiolysis, peptide hydrazides can be rapidly converted to peptide thioesters, which then selectively react with recombinant protein containing an N-terminal cysteine (Cys) to form a native peptide bond, thereby linking the two peptide segments without isolating any intermediates.

2.
Sci Total Environ ; 719: 137278, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32114223

RESUMO

The energy industry, one of the largest water consumers in the socioeconomic system, has been constrained by water scarcity in some areas worldwide. Therefore, decoupling water usage from the energy system is a pressing issue for ensuring energy security and maintaining environmental sustainability. This study applied an input-output analysis and the Tapio decoupling index, which may be considered the first attempt to investigate the decoupling degree between water usage, i.e., the direct water withdrawal for energy production (WWEP) from a production-based perspective and the water footprint for energy supply (WFES) from a consumption-based perspective, and industrial growth for five major energy sectors in China from 2002 to 2015. We found that WWEP was roughly three times higher than WFES for the whole energy industry, and both values underwent a considerable decrease during the study period. Production and supply of electricity and heat (PSEH) contributed most to the total WWEP and WFES, and was mainly responsible for the overall decline. Moreover, WFES exceeded WWEP in Processing of petroleum, coking, and processing of nuclear fuel (PPC) and Production and supply of gas (PSG), whose WEFS values accounted for 36.3% and 12.2%, respectively, of the total WFES in 2015. In terms of the decoupling status, only PSEH achieved strong decoupling in both WWEP and WFES, while PPC and PSG presented a better decoupling performance for WWEP than that for WFES. In contrast, Mining and washing of coal and Extraction of petroleum and natural gas performed relatively worse from both perspectives. These results can help provide a foundation and support for effective water conservation policies from both energy production and energy consumption perspectives.

3.
J Cell Mol Med ; 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32155686

RESUMO

Vascular smooth muscle cell (VSMC) proliferation is the pathological base of vascular remodelling diseases. Circular RNAs (circRNAs) are important regulators involved in various biological processes. However, the function of circRNAs in VSMC proliferation regulation remains largely unknown. This study was conducted to identify the key differentially expressed circRNAs (DEcircRNAs) and predict their functions in human aortic smooth muscle cell (HASMC) proliferation. To achieve this, DEcircRNAs between proliferative and quiescent HASMCs were detected using a microarray, followed by quantitative real-time RT-PCR validation. A DEcircRNA-miRNA-DEmRNA network was constructed, and functional annotation was performed using Gene Ontology (GO) and KEGG pathway analysis. The function of hsa_circ_0002579 in HASMC proliferation was analysed by Western blot. The functional annotation of the DEcircRNA-miRNA-DEmRNA network indicated that the four DEcircRNAs might play roles in the TGF-ß receptor signalling pathway, Ras signalling pathway, AMPK signalling pathway and Wnt signalling pathway. Twenty-seven DEcircRNAs with coding potential were screened. Hsa_circ_0002579 might be a pro-proliferation factor of HASMC. Overall, our study identified the key DEcircRNAs between proliferative and quiescent HASMCs, which might provide new important clues for exploring the functions of circRNAs in vascular remodelling diseases.

4.
Sensors (Basel) ; 20(5)2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155888

RESUMO

With the development of population aging, the recognition of elderly activity in smart homes has received increasing attention. In recent years, single-resident activity recognition based on smart homes has made great progress. However, few researchers have focused on multi-resident activity recognition. In this paper, we propose a method to recognize two-resident activities based on time clustering. First, to use a de-noising method to extract the feature of the dataset. Second, to cluster the dataset based on the begin time and end time. Finally, to complete activity recognition using a similarity matching method. To test the performance of the method, we used two two-resident datasets provided by Center for Advanced Studies in Adaptive Systems (CASAS). We evaluated our method by comparing it with some common classifiers. The results show that our method has certain improvements in the accuracy, recall, precision, and F-Measure. At the end of the paper, we explain the parameter selection and summarize our method.

5.
Phytochemistry ; 174: 112337, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32163787

RESUMO

Four undescribed sulfur-containing indole alkaloids, isatisindigoticanines H, I and isatindigosides F, G along with three known analogues were obtained from Isatis tinctoria L. roots. Isatisindigoticanines H and I contained an unusual 1-(thiazol-4-yl)butane-1,2,3,4-tetraol moiety while isatindigosides F and G possessed a new 3-[3-(1H-indole-2-yl)azet-2-yl]-1H-indole skeleton. The putative biosynthetic pathways of isatisindigoticanines H, I and isatindigosides F, G are proposed. The isolated compounds showed nitric oxide inhibitory effects with IC50 values ranging from 4.3 to 70.3 µM.

6.
Nat Commun ; 11(1): 1421, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32184391

RESUMO

Uncoupling protein-1 (UCP1) plays a central role in energy dissipation in brown adipose tissue (BAT). Using high-throughput library screening of secreted peptides, we identify two fibroblast growth factors (FGF), FGF6 and FGF9, as potent inducers of UCP1 expression in adipocytes and preadipocytes. Surprisingly, this occurs through a mechanism independent of adipogenesis and involves FGF receptor-3 (FGFR3), prostaglandin-E2 and interaction between estrogen receptor-related alpha, flightless-1 (FLII) and leucine-rich-repeat-(in FLII)-interacting-protein-1 as a regulatory complex for UCP1 transcription. Physiologically, FGF6/9 expression in adipose is upregulated by exercise and cold in mice, and FGF9/FGFR3 expression in human neck fat is significantly associated with UCP1 expression. Loss of FGF9 impairs BAT thermogenesis. In vivo administration of FGF9 increases UCP1 expression and thermogenic capacity. Thus, FGF6 and FGF9 are adipokines that can regulate UCP1 through a transcriptional network that is dissociated from brown adipogenesis, and act to modulate systemic energy metabolism.

7.
Environ Sci Technol ; 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32202769

RESUMO

Significance of reactive oxygen species (ROS) in subsurface has been increasingly documented in recent years, whereas the mechanisms controlling ROS production and distribution in subsurface remain poorly understood. Here we show that water table fluctuations regulate the dynamics of hydrogen peroxide (H2O2) production and distribution in unconfined aquifers. In one hydrological year, we measured the dynamics of H2O2 distribution in an unconfined aquifer impacted by a 14-m water level fluctuation in the adjacent Yangtze River. H2O2 concentrations in groundwater attained up to 123 nM at rising water table stage in summer, but were low or even below the detection limit at the other stages of stable and falling water table. Lab experiments and kinetic models revealed that abiotic reactions between dissolved O2 and reduced species (i.e., Fe(II) and organic matter) were responsible for H2O2 production in the aquifers. Both field observations and reactive transport models unveiled that rising water table developed a thermodynamically unstable banded zone in the unconfined aquifer in which elevated coexisting dissolved O2 and reduced species favored abiotic H2O2 production. Our findings provide fundamentals for understanding and predicting ROS distribution in unconfined aquifers, and constrain the significance of ROS in aquifers to specific temporal and spatial domains.

8.
Biomed Res Int ; 2020: 7539628, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32149132

RESUMO

Occlusal trauma caused by improper bite forces owing to the lack of periodontal membrane may lead to bone resorption, which is still a problem for the success of dental implant. In our study, to avoid occlusal trauma, we put forward a hypothesis that a microelectromechanical system (MEMS) pressure sensor is settled on an implant abutment to track stress on the abutment and predict the stress on alveolar bone for controlling bite forces in real time. Loading forces of different magnitudes (0 N-100 N) and angles (0-90°) were applied to the crown of the dental implant of the left central incisor in a maxillary model. The stress distribution on the abutment and alveolar bone were analyzed using a three-dimensional finite element analysis (3D FEA). Then, the quantitative relation between them was derived using Origin 2017 software. The results show that the relation between the loading forces and the stresses on the alveolar bone and abutment could be described as 3D surface equations associated with the sine function. The appropriate range of stress on the implant abutment is 1.5 MPa-8.66 MPa, and the acceptable loading force range on the dental implant of the left maxillary central incisor is approximately 6 N-86 N. These results could be used as a reference for the layout of MEMS pressure sensors to maintain alveolar bone dynamic remodeling balance.

9.
J Am Chem Soc ; 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32150680

RESUMO

During the past few decades, the study of the single polymer chain has attracted considerable attention with the goal of exploring the structure-property relationship of polymers. It still, however, remains challenging due to the variability and low atomic resolution of the amorphous single polymer chain. Here, we demonstrated a new strategy to visualize the single metallopolymer chain with a hexameric or trimeric supramolecule as a repeat unit, in which Ru(II) with strong coordination and Fe(II) with weak coordination were combined together in a stepwise manner. With the help of ultrahigh-vacuum, low-temperature scanning tunneling microscopy (UHV-LT-STM) and scanning tunneling spectroscopy (STS), we were able to directly visualize both Ru(II) and Fe(II), which act as staining reagents on the repeat units, thus providing detailed structural information for the single polymer chain. As such, the direct visualization of the single random polymer chain is realized to enhance the characterization of polymers at the single-molecule level.

10.
J Cell Mol Med ; 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32119762

RESUMO

SARI (Suppressor of AP-1, regulated by IFN-ß) is known to play an important role in some systemic disease processes such an inflammatory conditions and cancer. We hypothesize that SARI may also play a role in ocular diseases involving inflammation and neovascularization. To explore our hypothesis, further, we investigated an endotoxin-induced uveitis (EIU) and experimental argon laser-induced choroidal neovascularization (CNV) model in SARI wild-type (SARIWT ) and SARI-deficient (SARI-/- ) mice. Through imaging, morphological and immunohistochemical (IHC) studies, we found that SARI deficiency exacerbated the growth of CNV. More VEGF-positive cells were presented in the retina of SARI-/- mice with CNV. Compared to SARIWT  mice, more inflammatory cells infiltrated the ocular anterior segment and posterior segments in SARI-/- mice with EIU. Collectively, the results point to a potential dual functional role of SARI in inflammatory ocular diseases, suggesting that SARI could be a potential therapy target for ocular inflammation and neovascularization.

11.
Sleep Breath ; 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32002742

RESUMO

OBJECTIVES: Obstructive sleep apnea (OSA) and nonalcoholic fatty liver disease (NAFLD) are common in subjects with severe obesity. It has been suggested that insulin resistance and systemic inflammation may play a role in the development of nonalcoholic steatohepatitis (NASH), but the mechanisms remain controversial. The aim of this study was to explore the influence of OSA on liver injury and its potential mechanisms in severely obese patients with NAFLD. METHODS: Severely obese patients requiring bariatric surgery were consecutively recruited between November 2017 and June 2018. Demographic, biochemical, liver ultrasound, and ambulatory polygraph data were collected. RESULTS: One hundred fifty-three subjects with liver ultrasound-verified NAFLD were classified into three groups according to the apnea-hypopnea index (AHI). The level of serum alanine aminotransferase (ALT) and gamma-glutamyl transpeptidase (GGT) tended to increase with more severe OSA (P = 0.024 and P = 0.004, respectively). In the unadjusted analysis, both ALT and GGT were positively correlated with AHI, oxygen desaturation index, percentage of total sleep time spent with oxyhemoglobin saturation below 90%, male sex, homeostasis model assessment of insulin resistance (HOMA-IR), and total cholesterol, while liver enzymes were negatively related to lowest oxygen saturation. In multiple regression analysis, AHI (odds ratio (OR) = 1.052, P = 0.044) and HOMA-IR (OR = 1.135, P = 0.001) were independent risk factors for an elevated ALT level. High-sensitivity C-reactive protein (hs-CRP) was positively associated with BMI and GGT (r = 0.349 and r = 0.164 (P < 0.05), respectively), and no correlation was found between hs-CRP and AHI or other parameters of hypoxia. hs-CRP and GGT remained significantly correlated after adjusting for confounding parameters (OR = 2.509, P = 0.013). CONCLUSIONS: OSA may play a role in liver injury among severely obese individuals with NAFLD. Insulin resistance and systemic inflammation were possible contributing factors in this process.

12.
Nat Prod Res ; : 1-7, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32056448

RESUMO

Three new phenolic derivatives, picraquanines A-C (1-3), along with 6 known ones 4-9 were obtained from the stems of Picrasma quassioides (D. Don) Benn. The new structures were determined by extensive spectroscopic data analysis, including IR, HRESIMS, 1H-NMR, 13C-NMR, HSQC, HMBC, 1H-1H COSY experiments. The absolute configuration of 1 was determined by comparison of its experimental and calculated ECD spectra. Furthermore, all the compounds were tested for their nitric oxide (NO) inhibitory effects against LPS-stimulated RAW 264.7 cells, however, none of them exhibited inhibitory effects (IC50 >100 µM).[Figure: see text].

13.
Chem Commun (Camb) ; 56(20): 2987-2990, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32048633

RESUMO

The synergy among twelve carboxylates from two hexavalent baskets 16- assisted the encapsulation of one divalent diammonium guest 32+-62+ and the formation of ternary [3-6⊂12]10-. The reduction of basket's multivalency, by photoinduced α-decarboxylation of 16- to give 23-, intercepted the interannular cooperativity operating in the stabilization of capsulpex [3-6⊂12]10- to dramatically diminish the binding affinity towards diammonium guests. As a result, the cationic guests were released into bulk water with 23- assembling into nanoparticles. With numerous drugs carrying positive sites, the finding reported here could now be examined for their light-promoted spatiotemporal delivery.

15.
Mol Ther Nucleic Acids ; 19: 961-973, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32032888

RESUMO

Accumulating evidence has demonstrated that circular RNAs (circRNAs) play important roles in regulating gene expression involved in tumor development. However, the role of circRNAs in modulating the radiosensitivity of oral squamous cell carcinoma (OSCC) and its potential mechanisms have not been documented. We performed high-throughput RNA sequencing (RNA-seq) to investigate the circRNA expression profile in OSCC patients and discovered that the circATRNL1 expression was significantly downregulated and closely related to tumor progression. The circATRNL1 was structurally validated via Sanger sequencing, RNase R treatment, and specific convergent and divergent primer amplification. Importantly, the expression levels of circATRNL1 decreased after irradiation treatment, and upregulation of circATRNL1 enhanced the radiosensitivity of OSCC through suppressing proliferation and the colony survival fraction, inducing apoptosis and cell-cycle arrest. Moreover, we observed that circATRNL1 could directly bind to microRNA-23a-3p (miR-23a-3p) and relieve inhibition for the target gene PTEN. In addition, the tumor radiosensitivity-promoting effect of circATRNL1 overexpression was blocked by miR-23a-3p in OSCC. Further experiments also showed that PTEN can reverse the inhibitory effect of OSCC radiosensitivity triggered by miR-23a-3p. We concluded that circANTRL1 may function as the sponge of miR-23a-3p to promote PTEN expression and eventually contributes to OSCC radiosensitivity enhancement. This study indicates that circANTRL1 may be a novel therapeutic target to improve the efficiency of radiotherapy in OSCC.

16.
Chemosphere ; 248: 126065, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32045975

RESUMO

Two isoforms of Glutathione S-Transferase (GST) genes, belonging to mu (Dp-GSTm1 and Dp-GSTm2) and sigma (Dp-GSTs1 and Dp-GSTs2) classes, were cloned and characterised in the freshwater Daphnia pulex. No signal peptide was found in any of the four GST proteins, indicating that they were cytosolic GST. A highly conserved glutathione (GSH) binding site (G-site) occurred in the N-terminal sequence, and a substrate binding site (H-site), interacting non-specifically with the second hydrophobic substrate, was present in the C-terminal. A Tyr residue, for the stabilization of GSH, was found to be conserved in the analysed sequences. The secondary and tertiary structures indicated that these genes possess the typical cytosolic GST structure, including a conserved N-terminal domain with a ßαßαßßα motif. The µ loop (NVGPAPDYDR and NFIGAEWDR in Dp-GSTm1 and Dp-GSTm2, respectively) was identified between the ßαß (ß1α1ß2) and αßßα motifs (α2ß3ß4α3) in the N-terminal domain. The expressions of Dp-GSTs1, Dp-GSTs2, and Dp-GSTm1 were higher in other age groups compared to the newly-born neonates (1 d); however, the expression of Dp-GSTm2 first increased and then decreased with age. Gene expression was significantly reduced by high concentration (1 and 2 mg/L) of 75 nm polystyrene nanoplastic. However, nanoplastic exposure at the predicted environmental concentration (1 µg/L) had a low effect. Exposure of mothers to nanoplastic (1 µg/L) elevated the Dp-GSTs2 level in their neonates. These results improve our understanding on the response of different types of Daphnid GST to environmental contaminants, especially nanoplastic.

17.
Am J Dent ; 33(1): 17-24, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056410

RESUMO

PURPOSE: To review and assess the literature on in vitro studies evaluating tooth bleaching efficacy considering the use of a negative control, type of tooth substrate, storage medium, color evaluation methods, and evaluation time points. METHODS: The following databases were searched: PubMed (MEDLINE), Web of Science. Search used Medical Subject Headings (MeSH) in PubMed in addition to free text. The following limits were applied: English, articles published between January 1989 and October 2017. Additional free text key terms included: in vitro, tooth bleaching, placebo, negative control, overall CIELAB color change (ΔE*ab), change in shade guide units (ΔSGU), tooth color stabilization, evaluation time points, bovine teeth, and staining. Search was repeated in Web of Science but no additional articles were identified. A total of 11 studies were included for qualitative and quantitative analysis. RESULTS: The meta-analysis of nine included studies that reported ΔE*ab values, revealed that the NC statistically exceeded the perceptibility threshold (PT) of 1.2 (P< 0.05). The estimate was 2.872 with lower and upper bounds of 1.955 and 3.790, respectively. CLINICAL SIGNIFICANCE: Randomized controlled trials are gold standards to evaluate bleaching efficacy of different materials. However, in vitro studies offer a way to screen for potential bleaching efficacy. It is vital to determine an appropriate cut-off value for determining bleaching efficacy in vitro and further apply for clinical relevance.


Assuntos
Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Descoloração de Dente , Dente , Animais , Bovinos , Cor , Peróxido de Hidrogênio
18.
Obes Facts ; : 1-12, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32074620

RESUMO

INTRODUCTION: In the past two decades, urbanization in many Asian countries has led to sedentary lifestyle and overnutrition, which has set the stage for the epidemic of obesity. Those who have obesity during adolescence usually have obesity into adulthood, which causes many medical and psychological issues that can result in premature death. Recent data suggest that short sleep duration may contribute to the risk of obesity, opening a new avenue for potential intervention. The aim of this study was to describe the prevalence of sleeping time, body mass index (BMI), and fat mass in Chinese freshmen and to indicate the relationship among them. METHODS: We conducted a cross-sectional study consisting of 1,938 freshmen aged from 18 to 24 years, including 684 (35.3%) men and 1,254 (64.7%) women. BMI, sleeping time, and other potential related variables were collected by questionnaire. Obesity and overweight were defined as BMI ≥28.0 and ≥24.0, respectively. All students were divided into three groups according to the tertiles of body fat percentage (Fat%), which were measured by bioelectrical impedance analysis. Sleeping time was divided into 3 categories based on the duration, <6, 6-8, and >8 h per day. RESULTS: Participants who slept longer had lower BMI and Fat%. Sex, diet control, and maternal obesity were all significantly associated with BMI or Fat% after adjustment. There were significant differences between sleeping time <6 and >8 h in both overweight group and Fat% tertiles independent of adjustment used. The significant difference between sleeping time 6-8 and >8 h only existed in overweight group, while irrelevant relation was observed in both models of obesity group. CONCLUSION: Longer sleeping time was associated with a lower BMI in Chinese freshmen, even after adjustment for multiple confounders. The overweight stage is a critical period of weight management intervention by changing sleeping time. If adolescents have entered the obesity stage, the effect size of lifestyle intervention might be significantly limited.

19.
Artigo em Inglês | MEDLINE | ID: mdl-32078015

RESUMO

With the great success of anti-CTLA-4 and anti-PD-1 therapeutics in cancer immunotherapy, tumor necrosis factor receptor superfamily members have been recognized as ideal targets to provide co-stimulatory signals in combination with immune checkpoint blocking antibodies. Among these is OX40 (CD134), a co-stimulatory molecule expressed by activated immune cells. Recently, several anti-OX40 agonistic monoclonal antibodies, pogalizumab as the most advanced, have entered early phase clinical trials. Using a yeast platform and multiple screening methods, we identified a fully human anti-OX40 antibody (IBI101) with distinct modes of action. Unlike pogalizumab, IBI101 partially blocks the binding of OX40 to its ligand OX40L and exhibits both FcγR-dependent and independent agonistic activities in NF-κB luciferase reporter assays. IBI101 also promotes T cell activation and proliferation in vitro. These unique properties partially explain the more potent anti-tumor activity of IBI101 than that of pogalizumab in humanized NOG mice bearing LoVo tumors. In addition, IBI101 shows efficacious anti-tumor activity in mice when administrated alone or in combination with anti-PD-1 antibodies. In human OX40 knock-in mice bearing MC38 colon carcinoma, IBI101 treatment induces tumor antigen-specific CD8+ T-cell responses, decreases immunosuppressive regulatory T cells in tumor, and enhances the immune response to PD-1 inhibition. Preclinical studies of IBI101 in non-human primates demonstrate typical pharmacokinetic characteristics of an IgG antibody and no drug-related toxicity. Collectively, IBI101 has desirable preclinical attributes which support its clinical development for cancer treatment.

20.
BMC Cancer ; 20(1): 42, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31952506

RESUMO

Following publication of the original article [1], the authors reported an error in Fig 5 of this article, graphs presenting FCM and immunofluorescent for CD4T, CD8T and NK cell of the Control Groups (LL2, LL2-irradation, MCS-irradiation) were inadvertently duplicated from another parallel experiment.

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