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1.
Artigo em Inglês | MEDLINE | ID: mdl-33022778

RESUMO

TGF-ß signaling plays an extremely important role in the occurrence and development of type 2 diabetes mellitus (T2DM), and the blockade of TGF-ß/Smad3 pathway protests against the high-fat diet-induced obesity and diabetes. As a specific small molecule inhibitor of Smad3 protein, the biological activities of compound SIS3 were evaluated by high-fat diet-induced T2DM model mice. In vivo results indicated that SIS3 can not only significantly reduce the body weight, fat mass, fasting blood glucose in high-fat diet-induced T2DM model mice, but also improve insulin sensitivity and oral glucose tolerance of high-fat diet-induced T2DM model mice after the injection of SIS3 with 5 mg/kg for 45 days.

2.
Cells ; 9(10)2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33019728

RESUMO

Obesity is associated with increased breast cancer risk and poorer cancer outcomes; however, the precise etiology of these observations has not been fully identified. Our previous research suggests that adipose tissue-derived fibroblast growth factor-2 (FGF2) promotes the malignant transformation of epithelial cells through the activation of fibroblast growth factor receptor-1 (FGFR1). FGF2 is increased in the context of obesity, and increased sera levels have been associated with endocrine-resistant breast cancer. Leptin is a marker of obesity and promotes breast carcinogenesis through several mechanisms. In this study, we leverage public gene expression datasets to evaluate the associations between FGFR1, leptin, and the leptin receptor (LepR) in breast cancer. We show a positive association between FGFR1 and leptin protein copy number in primary breast tumors. These observations coincided with a positive association between Janus kinase 2 (Jak2) mRNA with both leptin receptor (LepR) mRNA and FGFR1 mRNA. Moreover, two separate Jak2 inhibitors attenuated both leptin+FGF2-stimulated and mouse adipose tissue-stimulated MCF-10A transformation. These results demonstrate how elevated sera FGF2 and leptin in obese patients may promote cancer progression in tumors that express elevated FGFR1 and LepR through Jak2 signaling. Therefore, Jak2 is a potential therapeutic target for FGFR1 amplified breast cancer, especially in the context of obesity.

3.
Sci Adv ; 6(41)2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33028531

RESUMO

RNAs form critical components of biological processes implicated in human diseases, making them attractive for small-molecule therapeutics. Expanding the sites accessible to nuclear magnetic resonance (NMR) spectroscopy will provide atomic-level insights into RNA interactions. Here, we present an efficient strategy to introduce 19F-13C spin pairs into RNA by using a 5-fluorouridine-5'-triphosphate and T7 RNA polymerase-based in vitro transcription. Incorporating the 19F-13C label in two model RNAs produces linewidths that are twice as sharp as the commonly used 1H-13C spin pair. Furthermore, the high sensitivity of the 19F nucleus allows for clear delineation of helical and nonhelical regions as well as GU wobble and Watson-Crick base pairs. Last, the 19F-13C label enables rapid identification of a small-molecule binding pocket within human hepatitis B virus encapsidation signal epsilon (hHBV ε) RNA. We anticipate that the methods described herein will expand the size limitations of RNA NMR and aid with RNA-drug discovery efforts.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33029929

RESUMO

A catalytic asymmetric alkylation of azoles with secondary 1-arylalkyl bromides through direct C-H functionalization is reported. Under blue light photoexcitation, copper(I)/carbazole-based bisoxazoline (CbzBox) catalytic system exhibits good reactivity and high stereoselectivity, thus offering an efficient strategy for constructing chiral alkyl azoles.

5.
Nat Commun ; 11(1): 5172, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33057164

RESUMO

The COVID-19 pandemic is impacting human activities, and in turn energy use and carbon dioxide (CO2) emissions. Here we present daily estimates of country-level CO2 emissions for different sectors based on near-real-time activity data. The key result is an abrupt 8.8% decrease in global CO2 emissions (-1551 Mt CO2) in the first half of 2020 compared to the same period in 2019. The magnitude of this decrease is larger than during previous economic downturns or World War II. The timing of emissions decreases corresponds to lockdown measures in each country. By July 1st, the pandemic's effects on global emissions diminished as lockdown restrictions relaxed and some economic activities restarted, especially in China and several European countries, but substantial differences persist between countries, with continuing emission declines in the U.S. where coronavirus cases are still increasing substantially.

6.
Hemodial Int ; 2020 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33040490

RESUMO

BACKGROUND: Superior vena cava occlusion (SVCO) induced by tunneled central venous catheter (tCVC) is an uncommon but challenging complication of hemodialysis patients. The aim of this study was to access the efficacy, safety, and patency of stents in tCVC-related SVCO via through-and-through technique. METHOD: We retrospectively identified seven patients with benign SVCO secondary to tCVC treated with endovascular approaches successfully between 1 March 2013 and 31 October 2019. Patients' demographic data, clinical signs and symptoms, and imaging data were followed up and recorded. RESULTS: Technical success was achieved in all cases. All the patients were performed with percutaneous transcatheter angioplasty (PTA) and subsequently stent placement via the through-and-through technique. During follow-up, four patients underwent secondary interventions, including PTA and/or stent placement. The primary patency after 3, 6, 9 and 12 months was 100%, 100%, 86% and 86%, and secondary patency after 12 months was 100%. No procedure-related deaths occurred. CONCLUSIONS: Endovascular management of SVCO is a safe and effective approach. CT examination can provide a direction for endovascular treatment and periodic surveillance.

7.
Chemosphere ; 264(Pt 1): 128427, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33002800

RESUMO

Eleven years (2005-2015) of data from long-term monitoring at a Japanese remote background site in Wajima, were analyzed to investigate temporal trends and sources. Water-soluble inorganic ions (WSIIs) were analyzed for aerosol chemical composition. The total WSIIs concentration was 7.93 ± 3.93 µg/m3, accounting for 42.3% of TSP mass, ranged from 11.4 to 93.9%. SO42- is the most abundant ion, contributing a total WSII mass from 18.0 to 79.8%, and non-sea-salt (nss-) SO42- contributed from 63.6% to 99.6% of total SO42-, which was related to human activities on the Asian continent and the effects of marine precursors in spring and summer, respectively. NO3- and NH4+ contribute 6.3 and 7.4% of the total WSIIs and were affected by long-range transport and local sources as well. The increasing trend of Na+ and Cl- indicates the increased influence of sea salt, which is caused by more frequent strong winds. K+ is mainly produced from biomass burning with a stable seasonal variation, Ca2+ as the characteristic ion of dust has the highest concentration in spring. Mg2+ comes from minerals and marine sources during spring and summer, respectively. This work describes in detail the annual change trend of the WSIIs of atmospheric particles in the Wajima area, seasonal characteristics, and source contributions, provide a comprehensive understanding of long-term variation in atmospheric particulate.

8.
Sci Data ; 7(1): 318, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004808

RESUMO

The spatial mismatch of energy resources and electricity demand in China drives the large-scale construction of power transmission infrastructure, which consumes a large amount of carbon-intensive products. However, a systematic accounting framework for the carbon emissions of power transmission infrastructure has not yet been established. This study for the first time compiles an embodied carbon emissions inventory covering 191 typical power transmission infrastructure projects in China in 2015, including 145 types of alternating current (AC) transmission line projects, 37 typical AC substation projects, 8 typical direct current (DC) transmission line projects and 1 typical DC converter station project. The inventory also shows the detailed inputs of all the projects. These data not only enable a quantitative assessment of the embodied carbon emissions of power transmission infrastructure in China but also provide essential information for climate mitigation policy design in the power sector.

9.
Artigo em Inglês | MEDLINE | ID: mdl-32939875

RESUMO

Monolithically integrated hybrid tandem solar cells (TSCs) that combine solution-processed colloidal quantum dot (CQD) and organic molecules are a promising device architecture, able to complement the absorption across the visible to the infrared. However, the performance of organic/CQD hybrid TSCs has not yet surpassed that of single-junction CQD solar cells. Here, a strategic optical structure is devised to overcome the prior performance limit of hybrid TSCs by employing a multibuffer layer and a dual near-infrared (NIR) absorber. In particular, a multibuffer layer is introduced to solve the problem of the CQD solvent penetrating the underlying organic layer. In addition, the matching current of monolithic TSCs is significantly improved to 15.2 mA cm-2 by using a dual NIR organic absorber that complements the absorption of CQD. The hybrid TSCs reach a power conversion efficiency (PCE) of 13.7%, higher than that of the corresponding individual single-junction cells, representing the highest efficiency reported to date for CQD-based hybrid TSCs.

10.
Artigo em Inglês | MEDLINE | ID: mdl-32966125

RESUMO

Pulmonary arterial hypertension (PAH) is a rare and lethal disease characterized by vascular remodeling and vasoconstriction, which is associated with increased intracellular calcium ion (Ca2+) concentration. Platelet-derived growth factor-BB (PDGF-BB) is the most potent mitogen for pulmonary arterial smooth muscle cells (PASMCs) and involved in vascular remodeling during PAH development. PDGF signaling has been proved to participate in maintaining Ca2+ homeostasis of PASMCs, however, the mechanism needs to be further elucidated. Here we illuminate that the expression of PMCA4 was downregulated in PASMCs after PDGF-BB stimulation, which was abolished by MEK/ERK inhibition. Functionally, suppression of PMCA4 attenuated the intracellular Ca2+ ([Ca2+]i) clearance in PASMCs after Ca2+ entry, promoting cell proliferation and elevating cells locomotion through mediating formation of focal adhesion. Additionally, the expression of PMCA4 was decreased in the pulmonary artery of MCT- or hypoxia-induced PAH rats. Moreover, knockdown of PMCA4 could increase the right ventricular systolic pressure and wall thickness of pulmonary artery in rats raised under normal condition. Taken together, our data proved the importance of the PDGF/MEK/ERK/PMCA4 axis in intracellular Ca2+ homeostasis in PASMCs, indicating a functional role of PMCA4 in pulmonary arterial remodeling and PAH development.

12.
Materials (Basel) ; 13(17)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887240

RESUMO

Secondary aluminum dross (SAD) is regarded as a solid waste of aluminum recycling process that creates serious environmental and health concerns. However, SAD can also be used as a good source of aluminum, so that utilizing the SAD for the production of valuable products is a promising approach of recycling such waste. In the present work, a novel eco-friendly three-step process was proposed for the synthesis of cryolite (Na3AlF6) from the SAD, and it consisted of (1) water-washing pretreatment of SAD, (2) extraction of Al component via pyro-hydrometallurgy, including low-temperature alkaline smelting, water leaching and purification of leachate in sequence, (3) precipitation of cryolite from the purified NaAlO2 solution using the carbonation method. By analysis of the parameter optimization for each procedure, it was found that the maximum hydrolysis efficiency of aluminum nitride (AlN) in the SAD was around 68.3% accompanied with an extraction efficiency of Al reaching 91.5%. On this basis, the cryolite of high quality was synthesized under the following optimal carbonation conditions: reaction temperature of 75 °C, NaAlO2 concentration of 0.11 mol/L, F/(6Al) molar ratio of 1.10, and 99.99% CO2 gas pressure, and flow rate of 0.2 MPa and 0.5 L/min respectively. The formation of Na3AlF6 phase can be detected by XRD. The morphological feature observed by SEM revealed that the as-synthesized cryolite had a polyhedral shape (~1 µm size) with obvious agglomeration. The chemical composition and ignition loss of the as-synthesized cryolite complied well with the requirements of the Chinese national standard (GB/T 4291-2017).

13.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(4): 385-392, 2020 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-32865356

RESUMO

OBJECTIVE: To evaluate the effect of scaling and root planing (SRP) on serum C-reactive protein (CRP) levels in patients with moderate to severe chronic periodontitis. METHODS: We searched the PubMed, Web of Science, EMBASE, Cochrane, CNKI, Wanfang, and VIP databases from the inception to July 8th, 2019. Two reviewers independently screened literature, extracted data, and evaluated the bias risk of included studies. Then, a meta-analysis was performed using RevMan 5.3 software. RESULTS: A total of 13 randomized controlled clinical trials and 12 prospective clinical trials were included. Meta-analysis showed that serum CRP levels decreased at 2 and 3 months after SRP (P<0.05), and no significant difference in serum CRP levels was found at 6 months (P=0.49). CONCLUSIONS: SRP can reduce serum CRP levels in systematically healthy patients with moderate to severe chronic periodontitis at 2 and 3 months after SRP.


Assuntos
Periodontite Crônica , Proteína C-Reativa , Raspagem Dentária , Humanos , Estudos Prospectivos , Aplainamento Radicular
14.
World J Gastroenterol ; 26(30): 4501-4522, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32874061

RESUMO

BACKGROUND: No guideline recommends antiviral therapy for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients with persistently normal alanine aminotransferase levels and a high hepatitis B virus (HBV) DNA viral load. AIM: To evaluate the feasibility and safety of a Chinese herbal formula as a therapeutic option for chronic HBV infection. METHODS: In total, 395 patients (30-65 years old) with confirmed HBeAg-positive chronic hepatitis B infection and persistently normal alanine aminotransferase were randomized to receive either Chinese herbal formula or placebo for 96 wk. Endpoints to evaluate therapeutic efficacy included: (1) HBV DNA levels decreased to less than 4 log10 IU/mL at weeks 48 and 96; and (2) HBeAg clearance and seroconversion rates at weeks 48 and 96. RESULTS: HBV DNA levels ≤ 4 log10 IU/mL were 10.05% at week 48 and 18.59% at week 96 in the treatment group. The HBeAg clearance and conversion rates were 8.54% and 8.04% at week 48 and 16.08% and 14.57% at week 96, respectively. However, HBV DNA levels ≤ 4 log10 IU/mL were 2.55% and 2.55% at weeks 48 and 96, respectively, and the HBeAg clearance rates were 3.06% and 5.61% at weeks 48 and 96, respectively, in the control group. The quantitative hepatitis B surface antigen and HBeAg levels at baseline and changes during the treatment period as well as the alanine aminotransferase elevation at weeks 12 and 24 were strong predictors of HBeAg clearance. CONCLUSION: High rates of HBV DNA reduction, HBeAg clearance and seroconversion could be achieved with Chinese herbal formula treatments, and the treatments were relatively safe for HBeAg-positive chronic hepatitis B-infected patients with persistently normal alanine aminotransferase. The ability of the compound to modulate host immune function probably contributed to this effect.

15.
Cancer Res Treat ; 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32878425

RESUMO

Purpose: This study attempted to detect the changes of cervical cancer screening rate and willingness among female migrants, and the associated socio-demographic factors in Shenzhen city. Materials and Methods: Two citywide surveys were conducted using a multistage random cluster sampling method in 2011 and 2014, respectively. Data on demographic characteristics, screening participation, and willingness to screen were collected. Logistic regression models were applied to detect possible associated socio-demographic characteristics, and their variations with survey years. Results: In total, 12,017 female migrants were enrolled, with a mean age (standard deviation) of 36.73 (6.55) years. From 2011 to 2014, the screening rate increased (25.8% vs. 35.1%, p<0.001), while the willingness to screen remained stable (82.2% vs. 82.8%, p=0.46). Overall, socio-demographic characteristics of female migrants, including age, marital status, education, monthly income, employment, and medical insurance, were found to be positively associated with screening participation. Similar impacts in relation to willingness were observed except for age. However, these associations varied with survey years, mainly in the contributions of education and monthly income to screening participation, as well as age, monthly income, and medical insurance to willingness of being screened. Conclusion: Identifying changes of associated socio-demographic factors precisely is warranted of necessity, which provides novel clues to adjust targeted actions regularly in promoting cervical cancer screening participation among female migrants in Shenzhen.

16.
BMC Pediatr ; 20(1): 418, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32878600

RESUMO

BACKGROUND: To explore the relationship between the pathological changes of the colon, terminal ileum, lung, liver and kidney, and the changes of Bax, PCNA and PAF in a rat model of NEC. METHODS: One hundred and forty neonatal SD rats were randomly divided into NEC group and control group (70 in each group). NEC group was given hypoxia, cold stimulation and artificial feeding twice a day for 3 consecutive days. The control group was only fed normally. After modeling, From the 1st day to the 7th day, 10 rats were sampled in each group for pathological examination of colon, terminal ileum, lung, liver and kidney tissue. The levels of Bax, PCNA and PAF were investigated by immunohistochemistry. RESULTS: Compared with the normal group, in the NEC group, on the 1st day, the colon, terminal ileum, lung, liver and kidney showed inflammatory damage. On the 5th day, the inflammatory injury was reduced. The inflammation disappeared on the 7th day. There were differences in the time of apoptosis in the intestine. In the intestine, the proliferation of PCNA was weak at first and then strong. Bax in liver and kidney showed marked apoptosis and apoptosis time increased in the lung. The expression of PCNA increased in lung, liver and kidney, and the expression of PAF increased in lung and liver. CONCLUSIONS: NEC can lead to secondary injury of different degrees in colon, terminal ileum, lung, liver and kidney, and the degree and time of injury and repair were different. In general, organ repair played a leading role on the 4th day after modeling.

17.
Sci Rep ; 10(1): 14412, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32879362

RESUMO

Clear cell renal cell carcinoma (ccRCC) is the most common type of renal cell carcinoma (RCC). Despite the existing extensive research, the molecular and pathogenic mechanisms of ccRCC are elusive. We aimed to identify the immune-related lncRNA signature and molecular subtypes associated with ccRCC. By integrating 4 microarray datasets from Gene Expression Omnibus database, we identified 49 immune-related genes. The corresponding immune-related lncRNAs were further identified in the TCGA dataset. 12-lncRNAs prognostic and independent signature was identified through survival analysis and survival difference between risk groups was further identified based on the risk score. Besides, we identified 3 molecular subtypes and survival analysis result showed that cluster 2 has a better survival outcome. Further, ssGSEA enrichment analysis for the immune-associated gene sets revealed that cluster 1 corresponded to a high immune infiltration level. While cluster 2 and cluster 3 corresponded to low and medium immune infiltration level, respectively. In addition, we validated the 12-lncRNA prognostic signature and molecular subtypes in an external validation dataset from the ICGC database. In summary, we identified a 12-lncRNA prognostic signature which may provide new insights into the molecular mechanisms of ccRCC and the molecular subtypes provided a theoretical basis for personalized treatment by clinicians.

18.
Endocrine ; 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948949

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

19.
Artigo em Inglês | MEDLINE | ID: mdl-32969568

RESUMO

Understanding the particular mechanisms by which vulnerability and capability factors influence cognitive reactivity (CR) can contribute to an enhanced capacity to adequately react to depression. However, few studies have explored the CR model. The main aim of the present study was to develop a model that specifies the predictive effects of CR for depression among individuals at high risk for first-episode and recurrent depression. A national cross-sectional, online study using convenience sampling was conducted among 587 vulnerable healthy individuals and 224 depressed patients in China. A battery of indices, including measures of CR, social support, resilience, self-compassion, life events, neuroticism, sleep condition, and negative emotion, were collected. A structural equation model was applied to analyse the data. The final first-episode and recurrent depressive symptoms of the CR models showed good model fit. According to the models, 45%-52% of the variance in depressive symptom was predicted by CR. Social support, self-compassion, resilience, and positive life events directly influenced CR, with ß values ranging from -0.18 to -0.24 (P < 0.01). Neuroticism, negative emotion, poor sleep conditions, and negative life events also directly and positively influenced CR (P < 0.01). The relationship between these negative or positive contributing factors and depression was also indirectly influenced by CR (P < 0.01). Our findings demonstrate the role of CR in the prevention and treatment of depression. The first-episode and recurrent depressive symptoms of the CR models considering both vulnerabilities and capabilities of CR in the psychopathology of depression provide a theoretical basis for interventions that reduce CR in high-risk populations.

20.
J Am Chem Soc ; 142(38): 16218-16222, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32881493

RESUMO

The potential applications of metal-organic cages (MOCs) are mostly achieved through specific host-guest interactions within their cavities. Electronic applications would require an effective electron transport pathway, which has been extensively studied in hybrid organic-inorganic materials with extended structures. These properties have not been considered for MOCs because cage-to-cage interactions in these materials have rarely been examined and are challenging to functionalize. We report here a previously unobserved actinide-based MOC assembled from four hexagonal-bipyramidal-coordinated uranyl ions and six bidentate flexible ligands. Remarkably, each isolated cage is further interlocked with six adjacent ones through mechanical bonds, resulting in the first case of a 0D → 3D f-element polycatenated metal-organic cage, SCU-14. Long-range π-π stacking extending throughout the structure is built via polycatenation, providing a visible carrier transmission path. SCU-14 is also an extremely rare case of an intrinsically semiconductive MOC with a wide band gap of 2.61 eV. Combined with the high X-ray attenuation efficiency, SCU-14 can effectively convert X-ray photons to electrical current signals and presents a promising sensitivity of 54.93 µC Gy-1 cm-2.

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