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1.
ACS Synth Biol ; 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33017143

RESUMO

Several microbes are polyploid, meaning they contain several copies of their chromosome. Cyanobacteria, while holding great potential as photosynthetic cell factories of various products, are found among them. In these clades the diversity of genetic elements that serve within the basic molecular toolbox is often limiting. To assist mining for the latter, we present here a method for the generation of fully segregated genomic libraries, specifically designed for polyploids. We provide proof-of-principle for this method by generating a fully segregated genomic promoter library in the cyanobacterium Synechocystis sp. PCC 6803. This new tool was first analyzed through fluorescence activated cell sorting (FACS) and then a fraction was further characterized regarding promoter sequence. The location of libraries on the chromosome provides a better reflection of the behavior of its elements. Our work presents the first method for constructing fully segregated genomic libraries in polyploids, which may facilitate their usage in synthetic biology applications.

2.
Int J Mol Sci ; 21(19)2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33019721

RESUMO

Recent studies uncover that subcellular location of long non-coding RNAs (lncRNAs) can provide significant information on its function. Due to the lack of experimental data, the number of lncRNAs is very limited, experimentally verified subcellular localization, and the numbers of lncRNAs located in different organelle are wildly imbalanced. The prediction of subcellular location of lncRNAs is actually a multi-classification small sample imbalance problem. The imbalance of data results in the poor recognition effect of machine learning models on small data subsets, which is a puzzling and challenging problem in the existing research. In this study, we integrate multi-source features to construct a sequence-based computational tool, lncLocation, to predict the subcellular location of lncRNAs. Autoencoder is used to enhance part of the features, and the binomial distribution-based filtering method and recursive feature elimination (RFE) are used to filter some of the features. It improves the representation ability of data and reduces the problem of unbalanced multi-classification data. By comprehensive experiments on different feature combinations and machine learning models, we select the optimal features and classifier model scheme to construct a subcellular location prediction tool, lncLocation. LncLocation can obtain an 87.78% accuracy using 5-fold cross validation on the benchmark data, which is higher than the state-of-the-art tools, and the classification performance, especially for small class sets, is improved significantly.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32897620

RESUMO

Transition metal chalcogenides (TMCs) are efficient oxygen evolution reaction (OER) pre-electrocatalysts, and will in situ transform into metal (oxy)hydroxides under OER condition. However, the role of chalcogen is not fully elucidated after oxidation and severe leaching. Here we present the vital promotion of surface-adsorbed chalcogenates on the OER activity. Taking NiSe2 as an example, in situ Raman spectroscopy revealed the oxidation of Se-Se to selenites (SeO3 2- ) then to selenates (SeO4 2- ). Combining the severe Se leaching and the strong signal of selenates, it is assumed that the selenates are rich on the surface and play significant roles. As expected, adding selenites to the electrolyte of Ni(OH)2 dramatically enhance its OER activity. And sulfates also exhibit the similar effect, suggesting the promotion of surface-adsorbed chalcogenates on OER is universal. Our findings offer unique insight into the transformation mechanism of materials during electrolysis.

4.
Org Lett ; 22(19): 7617-7621, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32940478

RESUMO

An enantioselective cascade reaction of N-alkylpyridinium and -quinolinium salts with o-hydroxybenzylideneacetones to access fused polyheterocycles through cross dienamine-mediated addition followed by trapping of the dearomatized enamine-type intermediates and aminal formation has been developed. A cascade assembly of N-benzyl-4-methylpyridinium salt and cyclic 2,4-dienones is further disclosed to give bridged frameworks via repetitive dearomatization and aromatization activation.

5.
Mol Brain ; 13(1): 130, 2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32972446

RESUMO

The goal of the present study was to elucidate the mechanism by which long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (lncRNA MALAT1) promotes inflammation in Parkinson's disease (PD). 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was used to induce PD development in C57BL/6 mice, and tyrosine hydroxylase (TH) expression was analysed by immunohistochemical analysis. Western blot and qPCR analyses were conducted to assess the expression of protein and mRNA levels, respectively. Lipopolysaccharide/adenosine triphosphate (LPS/ATP) was used to activate microglia in vitro. Chromatin immunoprecipitation (ChIP), RNA pull-down and RNA immunoprecipitation chip (RIP) assays were performed to investigate the interaction among specific molecules. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to evaluate cell viability and proliferation. Flow cytometry was performed to analyse cell apoptosis after staining. The dichlorofluorescein diacetate (DCFH-DA) assay was used to measure the generation of reactive oxygen species (ROS) in cells. The results showed that MALAT1 was highly expressed in the brains of MPTP-induced PD model mice and in LPS/ATP-induced microglia cells. Knockdown of MALAT1 inhibited elevated nuclear factor (erythroid-derived 2)-like-2 factor (NRF2) expression, thereby inhibiting inflammasome activation and ROS production. MALAT1 was shown to promote neuroinflammation by recruiting enhancer of zeste homologue 2 (EZH2) to the promoter of NRF2, suppressing Nrf2 expression. In summary, MALAT1 epigenetically inhibits NRF2, thereby inducing inflammasome activation and reactive oxygen species (ROS) production in PD mouse and microglial cell models.

6.
Crit Care ; 24(1): 554, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917257

RESUMO

BACKGROUND: To investigate the epidemiology and in-hospital mortality of veno-venous (VV) and veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) in Mainland China throughout 2018. METHODS: Patients supported by ECMO from 1700 tertiary hospitals in 31 provinces from January 1 to December 31, 2018, were selected from the National Clinical Improvement System database. RESULTS: The 1700 included hospitals had 2073 cases of ECMO in 2018, including 714 VV and 1359 VA ECMOs. The average patient age was 50 years (IQR 31-63), and 1346 were male. The average hospital stay was 17 days (IQR 7-30), and the average costs per case was $36,334 (IQR 22,547-56,714). The three provinces with the highest number of ECMO cases were Guangdong, Beijing, and Zhejiang; the southeast coastal areas and regions with higher GDP levels had more cases. Overall in-hospital mortality was 29.6%. Mortality was higher among patients who were male, over 70 years old, living in underdeveloped areas, and who were treated during the summer. Mortality in provinces with more ECMO cases was relatively low. The co-existence of congenital malformations, blood system abnormalities, or nervous system abnormalities increased in-hospital mortality. CONCLUSIONS: Mortality and medical expenses of ECMO among patients in China were relatively low, but large regional and seasonal differences were present. Risk factors for higher in-hospital mortality were older age, male sex, in underdeveloped areas, and treatment during the summer. Additionally, congenital malformations and blood system and nervous system abnormalities were associated with in-hospital mortality.

8.
Medicine (Baltimore) ; 99(37): e22096, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32925752

RESUMO

BACKGROUND: Adverse outcomes after unilateral vs bilateral breast reconstruction involve an unknown level of risk that warrants thorough investigation. METHODS: To address this research need, PubMed, Ovid, Medline, EMBASE, and Scopus databases were searched through systematically from January 1, 1990, to January 1, 2019 to retrieve the relevant studies on the risk of postoperative complications after unilateral vs bilateral abdominal flap breast reconstruction. According to the pre-designed inclusion criteria, available data were extracted from the relevant studies, and then analyzed comparatively in order to identify the relative risk (RR) and 95% confidence intervals (CI) applying either a random or a fixed effects model. RESULTS: Eventually, 20 studies involving 8122 female subjects met the inclusion criteria. It was found that unilateral reconstruction involved a significantly higher risk of flap loss (RR: 1.56, 95% CI: 1.21-2.00; P < .05) and fat necrosis (RR: 1.60, 95% CI: 1.23-2.09; P < .05) compared to bilateral reconstruction, while bilateral reconstruction involved a greater risk of abdominal hernia/bulge (RR: 1.67, 95% CI: 1.25-2.24; P < .05). The risk was found to be higher following bilateral free transverse rectus abdominis myocutaneous (fTRAM) flaps in comparison with deep inferior epigastric perforator (DIEP) flaps (RR: 2.62, 95% CI: 1.33-5.15; P < .05). CONCLUSION: The risk of postoperative flap complications in unilateral breast reconstruction is significantly higher than that in bilateral reconstruction. Contrarily, the abdominal complications were significantly higher in the bilateral group vs the unilateral group. Meanwhile, the risk of abdominal hernia/bulge complication after bilateral breast reconstruction was significantly higher with fTRAM vs DIEP. Therefore, DIEP flaps are recommended in priority for bilateral breast reconstruction, unless specifically contraindicated.


Assuntos
Mamoplastia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Retalhos Cirúrgicos/efeitos adversos , Feminino , Humanos
9.
Glob Public Health ; : 1-12, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32878539

RESUMO

Little was known about the role of health service utilisation on psychological distress. Using a national representative survey data in Australia, we aimed to quantify the role of disability status, types of disability, and severity of disability in their respective relationship to psychological distress in adults, and further explore the mediating effect of health service use on the disability-distress association. Data were derived from the 2015 Australian National Health Survey. Five individual actions taken for health were measured respectively, in terms of number of annual visits to general practitioner, specialist, outpatient clinic, hospital inpatient, and psychologist services. Disability was significantly associated with high psychological distress (OR = 4.46). Substantial increase in risk of high psychological distress was observed in people with psychological disability, head injury, stroke or brain damage, and intellectual disability (OR = 26.34, 18.26, 7.62). For the mediating effect of different health service use, GP services demonstrated the greatest decrease of the effect of disability on high psychological distress. GPs in the primary healthcare setting rather than psychological professionals hold a more important place to deal with the disabling and/or secondary clinical conditions as 'potential stressors'. Early screening provided by GPs for mental disorders are essential and integrated therapy will be beneficial.

10.
J Cell Mol Med ; 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32871042

RESUMO

Extracellular vesicle (EV)-associated microRNAs (miRNAs) have been found as the important biomarkers participating in the development of osteonecrosis of the femoral head (ONFH). Consequently, this study sought to examine the underlying mechanism of bone marrow mesenchymal stem cell (BMSC)-derived EVs containing miR-148a-3p in ONFH. The ONFH rat models were established. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis were applied to detect miR-148a-3p, Smad ubiquitination regulatory factor 1 (SMURF1), SMAD7 and B-cell CLL/lymphoma 2 (BCL2) expression, followed by determination of relationship between miR-148a-3p and SMURF1. BMSCs were isolated from normal rats and ONFH rats, and EVs were extracted from BMSCs of normal rats. BMSCs from ONFH rats were treated with mimic, inhibitor, small interfering RNA or EVs from miR-148a-3p mimic-treated BMSCs from normal rats (BMSC-EV-miR-148a-3p mimic). Cell Counting Kit-8 and alizarin red staining were utilized to detect cell viability and osteogenic differentiation of BMSCs. ONFH rats were injected with BMSC-EV-miR-148a-3p mimic to explore the function of BMSC-EV-delivered miR-148a-3p in vivo. miR-148a-3p was down-regulated in BMSCs and EVs from ONFH rats following decreased BMSCs viability and osteogenic differentiation. SMURF1 was a target gene of miR-148a-3p, and resulted in ubiquitination and degradation of SMAD7 to decreased BCL2 expression. The proliferation and differentiation of BMSCs were promoted by BMSC-EV-miR-148a-3p mimic or SMURF1 silencing. Additionally, BMSC-EV-miR-148a-3p mimic increased cell proliferation and osteogenic response, diminished SMURF1 expression, and elevated SMAD7 and BCL2 expression in ONFH rats. Collectively, miR-148a-3p overexpressed in BMSC-EVs promoted SMAD7 and BCL2 expression by inhibiting SMURF1, thus alleviating ONFH.

11.
Mater Sci Eng C Mater Biol Appl ; 117: 111344, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32919691

RESUMO

Myocardial tissue engineering has attracted increasing awareness for heart failure, and researchers are committed to developing an appropriate biological material to reconstruct myocardial tissues. Here, we applied a simple and high-throughput method to fabricate a three-dimensional (3D) partially reduced graphene oxide (PRGO) foam chip, whose structure, properties and biocompatibility confirmed that it is a suitable material for myocardial tissue engineering. The PRGO foam was produced based on a reduction reaction that occurred at the interface between the graphene oxide (GO) solution and Ni foam; as the Ni foam scaffold was dissolved in an HCl solution, the PRGO foam was harvested. After the PRGO foam was freeze-dried, its elasticity property was evaluated, and primary cardiomyocytes obtained from 2-day-old SD rats were cultured in the 3D foam. The results demonstrated good cell adherence, spreading, activity, organization and beating function in the PRGO foam during the long-term culturing process, which proved that the PRGO foam obtained by this method had application potential for myocardial tissue engineering.

13.
Stem Cells Int ; 2020: 8839703, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32963551

RESUMO

Mesenchymal stem cells (MSCs) present in multiple tissues can self-renew and differentiate into multiple lineages including the bone, cartilage, muscle, cardiac tissue, and connective tissue. Key events, including cell proliferation, lineage commitment, and MSC differentiation, are ensured by precise gene expression regulation. ATP-dependent chromatin alteration is one form of epigenetic modifications that can regulate the transcriptional level of specific genes by utilizing the energy from ATP hydrolysis to reorganize chromatin structure. ATP-dependent chromatin remodeling complexes consist of a variety of subunits that together perform multiple functions in self-renewal and lineage specification. This review highlights the important role of ATP-dependent chromatin remodeling complexes and their different subunits in modulating MSC fate determination and discusses the proposed mechanisms by which ATP-dependent chromatin remodelers function.

14.
J Ethnopharmacol ; 264: 113212, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32768643

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Cerebral ischemia-reperfusion (CIR) injury is one of the main diseases leading to death and disability. Acanthopanax senticosus (Rupr. & Maxim.) Harms (AS), also known as Panax ginseng, has neuroprotective effects on anti-CIR injury. However, the underlying molecular mechanism of its therapeutic effects is not clear. AIM OF THE STUDY: To systematically study and explore the mechanism of Acanthopanax senticosus (Rupr. & Maxim.) Harms extract (ASE) in the treatment of CIR injury based on metabolomics and transcriptomics. MATERIALS AND METHODS: The pharmacological basis of ASE in the treatment of CIR was evaluated, and samples were used in plasma metabolomics and brain tissue transcriptomics to reveal potential biomarkers. Finally, according to online database, we analyzed biomarkers identified by the two technologies, explained reasons for the therapeutic effect of ASE, and identify therapeutic targets. RESULTS: A total of 53 differential metabolites (DMs) were identified in plasma and 3138 differentially expressed genes (DEGs) were identified in brain tissue from three groups of rats, including sham, ischemia-reperfusion (I/R), and ASE groups. Enrichment analysis showed that Nme6, Tk1, and Pold1 that are involved in the production of deoxycytidine and thymine were significantly up-regulated and Dck was significantly down-regulated by the intervention with ASE. These findings indicated that ASE participates in the pyrimidine metabolism by significantly regulating the balance between dCTP and dTTP. In addition, ASE repaired and promoted the lipid metabolism in rats, which might be due to the significant expression of Dgkz, Chat, and Gpcpd1. CONCLUSIONS: The findings of this study suggest that ASE regulates the significant changes in gene expression in metabolites pyrimidine, and lipid metabolism in CIR rats and plays an active role in the treatment of CIR injury through multiple targets and pathways.

15.
ACS Nano ; 14(8): 9585-9593, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32806081

RESUMO

Today, tumor therapy and its therapeutic efficiency evaluation are conducted separately, and current imaging techniques cannot evaluate tumor-therapeutic effects in real time. Therefore, it is of great importance to develop highly efficient theranostic strategies which are able to evaluate their tumor-therapeutic effects in real time. In this work, by rational design of a small molecular near-infrared probe Cys(StBu)-Asp-Glu-Val-Asp-Lys(Cypate)-CBT (Cy-CBT) and using a CBT-Cys click condensation reaction, we facilely prepare an intelligent nanoparticle Cy-CBT-NP which is able to evaluate its photothermal therapy (PTT) efficiency on tumors by fluorescence "Turn-On". Fluorescence of Cy-CBT-NP is quenched and photothermal responsive. Upon caspase 3 (Casp3) cleavage of its DEVD substrates, Cy-CBT-NP disassembles to turn the fluorescence "On", which in turn evaluates the PTT efficiency of the nanoparticle on cells and tumors in real time. We envision that our smart strategy could be applied for PTT and real-time evaluation of the therapeutic efficiency of solid tumors in the near future.

16.
Radiol Infect Dis ; 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32838009

RESUMO

Objective: This study aimed to investigate the atypical computed tomography (CT) presentations of coronavirus disease 2019 (COVID-19) patients to comprehensively understand this highly infectious disease. Methods: The clinical and chest CT imaging data of 16 patients diagnosed with COVID-19 were retrospectively analyzed, and patients with atypical CT presentations were selected for analysis and review. Results: Of the 16 patients, 6 had atypical CT presentations, including 2 with faint ground glass opacities, 2 with single nodule, 1 with predominantly linear opacities, and 1 with predominantly reticular opacities. The dynamic changes of CT showed the faint ground glass opacities gradually became weak (2 cases). The scope of the single nodule was enlarged, and it developed into consolidation and residual fibrosis (2 cases). There was no obvious change of linear opacity (1 case). The reticular opacities were enlarged, then partially absorbed and new developed ground-glass opacities were found. Finally, the lesions were absorbed with residual fibrosis (1 case). Conclusion: Atypical CT presentations of COVID-19 can be classified as faint ground glass opacities, single nodule, linear opacities, and reticular opacities. Understanding the atypical presentation of COVID-19 is beneficial in the assessment and epidemic prevention and control of this disease.

17.
J Org Chem ; 85(16): 10760-10771, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32806086

RESUMO

An asymmetric intramolecular Rauhut-Currier reaction of linear bis(enones) has been achieved via double activation catalysis of thiols and phase transfer substances, furnishing both enantioenriched cyclohexene and cyclopentene derivatives (up to 95% ee). Furthermore, the desymmetric version of prochiral substrates was developed under similar catalysis, producing the frameworks bearing an additional tertiary or even quaternary stereogenic center with moderate to excellent diastereo- and enantioselectivity (up to 95% ee, >19:1 dr).

18.
Nanoscale ; 12(32): 16934-16943, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32776026

RESUMO

In this work, uniform and large gold nanoparticles (Au NPs) including quasi-spherical (QS) Au NPs with average diameters of 70 to 196 nm and trisoctahedral (TOH) Au NPs with average diameters of 140 to 195 nm were successfully synthesized by controlling the concentration of Cu2+ ions and the particle number of 3 nm Au-NP seeds, respectively, using a one-step seeded growth method with Cu2+-mediated Ostwald ripening. It is found that because of the concentration-dependent under-potential deposition of Cu2+ ions (CuUPD), 3 nm Au-NP seeds are firstly changed into Au NPs with a controlled QS- or TOH shape at the initial growth stage, followed by the conformal growth of Au atoms onto the initially formed Au NPs due to Cu2+-mediated Ostwald ripening, in which the extra Au atoms come from the dissolution of in situ Au nuclei by the unavoidable self-nucleation. Moreover, the as-prepared QS Au NPs with a rough surface exhibit a better SERS performance for physically adsorbed probes (crystal violet, CV) than the TOH Au NPs with sharp tips and with a comparable size. Furthermore, the as-prepared QS Au NPs can be used to distinguish nitrile and isonitrile groups by surface-enhanced Raman scattering (SERS) due to the presence of deformation twinnings. Thus, the as-prepared QS Au NPs with a rough surface and deformation twinnings can be further used as templates for the fabrication of bimetallic materials with multi-functionalities.

19.
BMC Gastroenterol ; 20(1): 279, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32819274

RESUMO

BACKGROUND: We aimed to compare the safety and effectiveness of the following procedures after pancreaticoduodenectomy: isolated pancreaticojejunostomy, isolated gastrojejunostomy, and conventional pancreaticojejunostomy. METHODS: We performed a systematic search of the following databases: PubMed, Embase, Web of Science, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov until 1 January 2020. Pooled odds ratios (OR) or weighted mean differences (WMD) with 95% confidence intervals (CIs) were calculated using STATA 12.0 statistical software. RESULTS: Thirteen studies involving 1942 patients were included in this study. Pooled analysis showed that reoperation rates following isolated pancreaticojejunostomy were lower reoperation than with conventional pancreaticojejunostomy (OR = 0.36, 95% CI: 0.15-0.86, p = 0.02, respectively), and that isolated pancreaticojejunostomy required longer operation time vs conventional pancreaticojejunostomy (WMD = 43.61, 95% CI: 21.64-65.58, P = 0.00). Regarding postoperative pancreatic fistula, clinically-relevant postoperative pancreatic fistula, delayed gastric emptying, clinically-relevant delayed gastric emptying, bile leakage, hemorrhage, reoperation, length of postoperative hospital stay, major complications, overall complications, and mortality, we found no significant differences for either isolated pancreaticojejunostomy versus conventional pancreaticojejunostomy or isolated gastrojejunostomy versus conventional pancreaticojejunostomy. CONCLUSIONS: This study showed that isolated pancreaticojejunostomy was associated with a lower reoperation rate, but required longer operation time vs conventional pancreaticojejunostomy. Considering the limitations, high-quality randomized controlled trials are required.

20.
J Hazard Mater ; 403: 123592, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32795824

RESUMO

Polycyclic aromatic hydrocarbon (PAH) contamination in agricultural soils (n = 41) along Shanghai road net was systematically investigated to characterize pollution distribution and to apportion sources. Total PAH (Σ16PAH) concentrations in roadside agricultural soils varied from 17.2 to 3775 ng/g with an average of 339 ± 594 ng/g, 43.9 % of which corresponded to weakly - heavily contaminated levels. The spatial distribution of pollution hotspots depended on heavy traffic volume and intensive industrial activities in adjacent areas. A positive matrix factorization receptor model identified that vehicle emission and combustion of coal, biomass and natural gas were the predominant sources, accounting for 66.0 % and 23.7 % of Σ16PAH loadings, respectively. Stable carbon isotope analysis was applied for the first time in seven sites with high Σ16PAH concentrations for tracing their unique sources. It was concluded that PAHs in the heavily contaminated soil site G18 predominantly came from vehicle emission sources, different from the six other sites controlled by coal-processing and biomass combustion sources. Future studies should focus on quantifying the source contribution of PAHs in roadside agricultural soils based on the combination of multi-isotope approaches due to the data overlap of δ13C in certain sources.

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