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1.
Nucleic Acids Res ; 51(21): 11770-11782, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37870428

RESUMO

Precision medicine depends on high-accuracy individual-level genotype data. However, the whole-genome sequencing (WGS) is still not suitable for gigantic studies due to budget constraints. It is particularly important to construct highly accurate haplotype reference panel for genotype imputation. In this study, we used 10 000 samples with medium-depth WGS to construct a reference panel that we named the CKB reference panel. By imputing microarray datasets, it showed that the CKB panel outperformed compared panels in terms of both the number of well-imputed variants and imputation accuracy. In addition, we have completed the imputation of 100 706 microarrays with the CKB panel, and the after-imputed data is the hitherto largest whole genome data of the Chinese population. Furthermore, in the GWAS analysis of real phenotype height, the number of tested SNPs tripled and the number of significant SNPs doubled after imputation. Finally, we developed an online server for offering free genotype imputation service based on the CKB reference panel (https://db.cngb.org/imputation/). We believe that the CKB panel is of great value for imputing microarray or low-coverage genotype data of Chinese population, and potentially mixed populations. The imputation-completed 100 706 microarray data are enormous and precious resources of population genetic studies for complex traits and diseases.


Assuntos
Bancos de Espécimes Biológicos , Genoma , Humanos , Haplótipos , Genótipo , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , China
2.
Gastroenterology ; 165(1): 61-70.e5, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37059339

RESUMO

BACKGROUND & AIMS: Evidence is sparse and inconclusive on the association between long-term fine (≤2.5 µm) particulate matter (PM2.5) exposure and esophageal cancer. We aimed to assess the association of PM2.5 with esophageal cancer risk and compared the esophageal cancer risk attributable to PM2.5 exposure and other established risk factors. METHODS: This study included 510,125 participants without esophageal cancer at baseline from China Kadoorie Biobank. A high-resolution (1 × 1 km) satellite-based model was used to estimate PM2.5 exposure during the study period. Hazard ratios (HR) and 95% CIs of PM2.5 with esophageal cancer incidence were estimated using Cox proportional hazard model. Population attributable fractions for PM2.5 and other established risk factors were estimated. RESULTS: There was a linear concentration-response relationship between long-term PM2.5 exposure and esophageal cancer. For each 10-µg/m3 increase in PM2.5, the HR was 1.16 (95% CI, 1.04-1.30) for esophageal cancer incidence. Compared with the first quarter of PM2.5 exposure, participants in the highest quarter had a 1.32-fold higher risk for esophageal cancer, with an HR of 1.32 (95% CI, 1.01-1.72). The population attributable risk because of annual average PM2.5 concentration ≥35 µg/m3 was 23.3% (95% CI, 6.6%-40.0%), higher than the risks attributable to lifestyle risk factors. CONCLUSIONS: This large prospective cohort study of Chinese adults found that long-term exposure to PM2.5 was associated with an elevated risk of esophageal cancer. With stringent air pollution mitigation measures in China, a large reduction in the esophageal cancer disease burden can be expected.


Assuntos
Neoplasias Esofágicas , Material Particulado , Adulto , Humanos , População do Leste Asiático , Exposição Ambiental/efeitos adversos , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/etiologia , Incidência , Material Particulado/efeitos adversos , Material Particulado/classificação , Estudos Prospectivos , China/epidemiologia , Fatores de Risco
3.
Biomacromolecules ; 25(5): 2965-2972, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38682378

RESUMO

Nucleic acid therapeutics have attracted recent attention as promising preventative solutions for a broad range of diseases. Nonviral delivery vectors, such as cationic polymers, improve the cellular uptake of nucleic acids without suffering the drawbacks of viral delivery vectors. However, these delivery systems are faced with a major challenge for worldwide deployment, as their poor thermal stability elicits the need for cold chain transportation. Here, we demonstrate a biomaterial strategy to drastically improve the thermal stability of DNA polyplexes. Importantly, we demonstrate long-term room temperature storage with a transfection efficiency maintained for at least 9 months. Additionally, extreme heat shock studies show retained luciferase expression after heat treatment at 70 °C. We therefore provide a proof of concept for a platform biotechnology that could provide long-term room temperature storage for temperature-sensitive nucleic acid therapeutics, eliminating the need for the cold chain, which in turn would reduce the cost of distributing life-saving therapeutics worldwide.


Assuntos
DNA , Humanos , DNA/química , Transfecção/métodos , Polímeros/química , Resposta ao Choque Térmico/efeitos dos fármacos , Temperatura , Temperatura Alta
4.
Environ Sci Technol ; 58(10): 4824-4836, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38408018

RESUMO

Electrochemically converting nitrate, a widely distributed nitrogen contaminant, into harmless N2 is a feasible and environmentally friendly route to close the anthropogenic nitrogen-based cycle. However, it is currently hindered by sluggish kinetics and low N2 selectivity, as well as scarce attention to reactor configuration. Here, we report a flow-through zero-gap electrochemical reactor that shows a high performance of nitrate reduction with 100% conversion and 80.36% selectivity of desired N2 in the chlorine-free system at 100 mg-N·L-1 NO3- while maintaining a rapid reduction kinetics of 0.07676 min-1. More importantly, the mass transport and current utilization efficiency are significantly improved by shortening the inter-electrode distance, especially in the zero-gap electrocatalytic system where the current efficiency reached 50.15% at 5 mA·cm-2. Detailed characterizations demonstrated that during the electroreduction process, partial Cu(OH)2 on the cathode surface was reconstructed into stable Cu/Cu2O as the active phase for efficient nitrate reduction. In situ characterizations revealed that the highly selective *NO to *N conversion and the N-N coupling step played crucial roles during the selective reduction of NO3- to N2 in the zero-gap electrochemical system. In addition, theoretical calculations demonstrated that improving the key intermediate *N coverage could effectively facilitate the N-N coupling step, thereby promoting N2 selectivity. Moreover, the environmental and economic benefits and long-term stability shown by the treatment of real nitrate-containing wastewater make our proposed electrocatalytic system more attractive for practical applications.


Assuntos
Nitratos , Águas Residuárias , Nitratos/química , Eletrodos , Nitrogênio/análise , Nitrogênio/química , Cinética
5.
Molecules ; 29(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38474694

RESUMO

In this study, the performance of a zero-gap flow-through reactor with three-dimensional (3D) porous Ti/RuO2-TiO2@Pt anodes was systematically investigated for the electrocatalytic oxidation of phenolic wastewater, considering phenol and 4-nitrophenol (4-NP) as the target pollutants. The optimum parameters for the electrochemical oxidation of phenol and 4-NP were examined. For phenol degradation, at an initial concentration of 50 mg/L, initial pH of 7, NaCl concentration of 10.0 g/L, current density of 10 mA/cm2, and retention time of 30 min, the degradation efficiency achieved was 95.05%, with an energy consumption of 15.39 kWh/kg; meanwhile, for 4-NP, the degradation efficiency was 98.42% and energy consumption was 19.21 kWh/kg (at an initial concentration of 40 mg/L, initial pH of 3, NaCl concentration of 10.0 g/L, current density of 10 mA/cm2, and retention time of 30 min). The electrocatalytic oxidation of phenol and 4-NP conformed to the pseudo-first-order kinetics model, and the k values were 0.2562 min-1 and 0.1736 min-1, respectively, which are 1.7 and 3.6-times higher than those of a conventional electrolyzer. Liquid chromatography-mass spectrometry (LC-MS) was used to verify the intermediates formed during the degradation of phenol or 4-NP and a possible degradation pathway was provided. The extremely narrow electrode distance and the flow-through configuration of the zero-gap flow-through reactor were thought to be essential for its lower energy consumption and higher mass transfer efficiency. The zero-gap flow-through reactor with a novel 3D porous Ti/RuO2-TiO2@Pt electrode is a superior alternative for the treatment of industrial wastewater.

6.
Biomacromolecules ; 24(11): 4587-4604, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37842883

RESUMO

Compartmentalization is a crucial feature of a natural cell, manifested in cell membrane and inner lumen. Inspired by the cellular structure, multicompartment polymersomes (MCPs), including membrane-compartmentalized polymersomes and lumen-compartmentalized polymersomes (polymersomes-in-polymersomes), have aroused great expectations for biological applications such as biocatalysis and cell mimics in the past decades. Compared with traditional polymersomes, MCPs have advantages in encapsulating multiple enzymes separately for multistep enzymatic cascade reactions. In this review, first, the design principles and preparation methods of membrane-compartmentalized and lumen-compartmentalized polymersomes are summarized. Next, recent advances of MCPs as nanoreactors and cell mimics to mimic subcellular organelles or artificial cells are discussed. Finally, the future research directions of MCPs are prospected.


Assuntos
Organelas , Biocatálise , Membrana Celular/metabolismo , Membranas , Organelas/metabolismo
7.
BMC Anesthesiol ; 23(1): 285, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37608299

RESUMO

BACKGROUND: Hypokalemia is common in patients of various operations, especially gastrointestinal surgery, which seriously affects the safety and enhanced recovery after surgery. Our study aims to explore the risk factors of preoperative hypokalemia of radical gastrectomy for gastric cancer and analyze its impact on postoperative recovery. METHODS: A total of 122 patients scheduled for radical gastrectomy from September, 2022 to December, 2022 were retrospectively analyzed. According to the serum potassium level before skin incision, patients were divided into hypokalemia group (n = 64) and normokalemia group (n = 58). Factors including age, gender, BMI, ASA classification, glutamic pyruvic transaminase (ALT), glutamic oxaloacetic transaminase (AST), creatinine, blood urea nitrogen (BUN), albumin, hypertension history, whether taking calcium channel blockers, ß-receptor blockers, angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor antagonist (ARB), thiazide diuretics and other drugs, anemia history, diabetes mellitus history, inability to eat or intestinal obstruction, vomiting, diarrhea, hypokalemia on admission and whether under cooperation with clinical nurse specialist were compared between groups. Univariate logistic regression analysis was used to determine risk factors for hypokalemia with p < 0.2 included as a cutoff. Multivariate logistic regression was used to analyze the influencing factors of preoperative hypokalemia for the indicators with differences. A receiver operating characteristic (ROC) curve was used to evaluate the efficacy of the regression model. Primary exhaust time and defecation time after surgery were compared between the two groups. RESULTS: The use of ACEI or ARB [OR 0.08, 95% CI (0.01 to 0.58), p = 0.012] and thiazide diuretics [OR 8.31, 95% CI (1.31 to 52.68), p = 0.025], inability to eat for more than 3 days or intestinal obstruction [OR 17.96, 95% CI (2.16 to 149.43), p = 0.008], diarrhea for more than 48 h [OR 6.21, 95% CI (1.18 to 32.61), p = 0.031] and hypokalemia on admission [OR 8.97, 95% CI (1.05 to 77.04), p = 0.046] were independent influencing factors of hypokalemia before skin incision. Primary postoperative exhaust time and defecation time was significantly longer in the hypokalemia group than in the normokalemia group, no matter after laparoscopic radical gastrectomy (p = 0.044, p = 0.045, respectively) or open radical gastrectomy (p = 0.033, p = 0.019, respectively). CONCLUSION: Early attention and management of serum potassium in patients undergoing radical gastrectomy can better reduce perioperative adverse reactions and promote recovery of gastrointestinal function.


Assuntos
Hipopotassemia , Humanos , Hipopotassemia/epidemiologia , Estudos Retrospectivos , Antagonistas de Receptores de Angiotensina , Inibidores de Simportadores de Cloreto de Sódio , Inibidores da Enzima Conversora de Angiotensina , Fatores de Risco , Gastrectomia/efeitos adversos , Diarreia , Potássio
8.
Molecules ; 28(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36903435

RESUMO

Electrocatalytic oxidation (ECO) has attracted attention because of its high efficiency and environmental friendliness in water treatment. The preparation of anodes with high catalytic activity and long service lifetimes is a core part of electrocatalytic oxidation technology. Here, porous Ti/RuO2-IrO2@Pt, Ti/RuO2-TiO2@Pt, and Ti/Y2O3-RuO2-TiO2@Pt anodes were fabricated by means of modified micro-emulsion and vacuum impregnation methods with high porosity titanium plates as substrates. The scanning electron microscopy (SEM) images showed that RuO2-IrO2@Pt, RuO2-TiO2@Pt, and Y2O3-RuO2-TiO2@Pt nanoparticles were coated on the inner surface of the as-prepared anodes to form the active layer. Electrochemical analysis revealed that the high porosity substrate could result in a large electrochemically active area, and a long service life (60 h at 2 A cm-2 current density, 1 mol L-1 H2SO4 as the electrolyte, and 40 °C). The degradation experiments conducted on tetracycline hydrochloride (TC) showed that the porous Ti/Y2O3-RuO2-TiO2@Pt had the highest degradation efficiency for tetracycline, reaching 100% removal in 10 min with the lowest energy consumption of 167 kWh kg-1 TOC. The reaction was consistent with the pseudo-primary kinetics results with a k value of 0.5480 mol L-1 s-1, which was 16 times higher than that of the commercial Ti/RuO2-IrO2 electrode. The fluorospectrophotometry studies verified that the degradation and mineralization of tetracycline were mainly ascribed to the •OH generated in the electrocatalytic oxidation process. This study thus presents a series of alternative anodes for future industrial wastewater treatment.

9.
Angew Chem Int Ed Engl ; 62(51): e202314045, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37916968

RESUMO

Self-assembly of subnanometer (sub-1 nm) scale polyhedral building blocks can yield some superstructures with novel and interesting morphology as well as potential functionalities. However, achieving the self-assembly of sub-1 nm polyhedral building blocks is still a great challenge. Herein, through encapsulating the titanium-substituted polyoxometalate (POM, K7 PTi2 W10 O40 ) with tetrabutylammonium cations (TBA+ ), we first synthesized a sub-1 nm rhombic dodecahedral building block by further tailoring the spatial distribution of TBA+ on the POM. Molecular dynamics (MD) simulations demonstrated the eight TBA+ cations interacted with the POM cluster and formed the sub-1 nm rhombic dodecahedron. As a result of anisotropy, the sub-1 nm building blocks have self-assembled into rhombic dodecahedral POM (RD-POM) assemblies at the microscale. Benefiting from the regular structure, Br- ions, and abundant active sites, the obtained RD-POM assemblies exhibit excellent catalytic performance in the cycloaddition of CO2 with epoxides without co-catalysts. This work provides a promising approach to tailor the symmetry and structure of sub-1 nm building blocks by tuning the spatial distribution of ligands, which may shed light on the fabrication of superstructures with novel properties by self-assembly.

10.
BMC Med ; 20(1): 354, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36266610

RESUMO

BACKGROUND: Little is known about the effects of maintaining healthy sleep patterns on frailty transitions. METHODS: Based on 23,847 Chinese adults aged 30-79 in a prospective cohort study, we examined the associations between sleep patterns and frailty transitions. Healthy sleep patterns included sleep duration at 7 or 8 h/d, without insomnia disorder, and no snoring. Participants who persisted with a healthy sleep pattern in both surveys were defined as maintaining a healthy sleep pattern and scored one point. We used 27 phenotypes to construct a frailty index and defined three statuses: robust, prefrail, and frail. Frailty transitions were defined as the change of frailty status between the 2 surveys: improved, worsened, and remained. Log-binomial regression was used to calculate the prevalence ratio (PR) to assess the effect of sleep patterns on frailty transitions. RESULTS: During a median follow-up of 8.0 years among 23,847 adults, 45.5% of robust participants, and 10.8% of prefrail participants worsened their frailty status, while 18.6% of prefrail participants improved. Among robust participants at baseline, individuals who maintained sleep duration of 7 or 8 h/ds, without insomnia disorder, and no-snoring were less likely to worsen their frailty status; the corresponding PRs (95% CIs) were 0.92 (0.89-0.96), 0.76 (0.74-0.77), and 0.85 (0.82-0.88), respectively. Similar results were observed among prefrail participants maintaining healthy sleep patterns. Maintaining healthy sleep duration and without snoring, also raised the probability of improving the frailty status; the corresponding PRs were 1.09 (1.00-1.18) and 1.42 (1.31-1.54), respectively. Besides, a dose-response relationship was observed between constantly healthy sleep scores and the risk of frailty transitions (P for trend < 0.001). CONCLUSIONS: Maintaining a comprehensive healthy sleep pattern was positively associated with a lower risk of worsening frailty status and a higher probability of improving frailty status among Chinese adults.


Assuntos
Fragilidade , Distúrbios do Início e da Manutenção do Sono , Humanos , Idoso , Fragilidade/epidemiologia , Idoso Fragilizado , Estudos Prospectivos , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Sono , China/epidemiologia
11.
Nature ; 540(7633): 354-362, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27974763

RESUMO

Renewable resources are used increasingly in the production of polymers. In particular, monomers such as carbon dioxide, terpenes, vegetable oils and carbohydrates can be used as feedstocks for the manufacture of a variety of sustainable materials and products, including elastomers, plastics, hydrogels, flexible electronics, resins, engineering polymers and composites. Efficient catalysis is required to produce monomers, to facilitate selective polymerizations and to enable recycling or upcycling of waste materials. There are opportunities to use such sustainable polymers in both high-value areas and in basic applications such as packaging. Life-cycle assessment can be used to quantify the environmental benefits of sustainable polymers.


Assuntos
Conservação dos Recursos Naturais , Polímeros/química , Polímeros/síntese química , Carboidratos/química , Dióxido de Carbono/química , Elasticidade , Eletrônica/instrumentação , Hidrogéis/síntese química , Hidrogéis/química , Óleos de Plantas/química , Plantas/química , Plásticos/síntese química , Plásticos/química , Terpenos/química
12.
J Cell Physiol ; 236(9): 6520-6533, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33576499

RESUMO

Pre-eclampsia (PE) is a pregnancy-related disorder that occurs after 20 weeks of gestation. It seriously affects the health of maternity and the fetus. However, the pathogenesis of PE is still unknown. Decidualization deficiency is considered a contributing factor to the development of PE. CTP synthetase (CTPS) which is the rate-limiting enzyme in the CTP de novo biosynthesis, is essential for nucleic acid synthesis and cellular energy metabolism, and often appears as cytoophidium in many cell types. Here, we found that the expression of CTPS was significantly downregulated in decidual tissues of patients with severe PE compared with healthy pregnant women. During in vitro decidualization, changes in CTPS were accompanied by opposite fluctuation of the AMPK signaling pathway. Moreover, the downregulation of CTPS by glutamine analogs or CTPS small interfering RNA inhibited the decidualization process and the AMPK signaling pathway. Investigating the underlying mechanism of action by co-immunoprecipitation coupled with mass spectrometry showed that CTPS interacted with ATP synthase (ATPS) and maintained the content of ATP on Day 3 of decidualization. However, when combined with mitochondrial stress protein STRESS-70 instead of ATPS, the concentration of ATP on Day 6 of induction was reduced. Corresponding to this, CTPS was mainly distributes in the cytoplasm on Day 3 of induction, while it appeared both in the cytoplasm and the nucleus on Day 6 in decidualized cells, which was similar to that in cells before induction. In summary, we believe that CTPS plays an important role in decidualization by participating in energy metabolism. Abnormal expression of CTPS in decidualization would lead to abnormal decidualization and consequently result in the occurrence of PE.


Assuntos
Carbono-Nitrogênio Ligases/metabolismo , Decídua/enzimologia , Regulação para Baixo , Metabolismo Energético , Pré-Eclâmpsia/enzimologia , Adenilato Quinase/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Diazo-Oxo-Norleucina/farmacologia , Regulação para Baixo/efeitos dos fármacos , Endométrio/patologia , Metabolismo Energético/efeitos dos fármacos , Feminino , Inativação Gênica/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Gravidez , Ligação Proteica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo
13.
J Reprod Dev ; 66(1): 19-27, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-31735743

RESUMO

One major side effect of chemotherapy that young women with cancer suffer from is ovarian damage. Therefore, it is necessary to study the pathogenesis of chemotherapeutic drugs in order to develop pharmaceutical agents to preserve fertility. Epirubicin is one of the commonly used chemotherapy drugs for breast cancer patients. This research explored the side effects of epirubicin in mice. We found that epirubicin significantly reduced the body weight, the weight of the ovaries and uteri, and the pups' number, while melatonin, which is extremely resistant to oxidation, significantly reduced these damages. Moreover, co-treatment with melatonin prevented epirubicin-induced decrease in E2 and progesterone, and the loss of follicles. Mechanism study showed that melatonin significantly reduced the levels of proapoptotic genes p53, Caspase3, and Caspase9 while it upregulated antiapoptotic factors Bcl-2 and Bcl2l1, and antioxidant genes superoxide dismutase 1 and catalase compared with the epirubicin group. In addition, melatonin markedly reduced reactive oxygen species (ROS) and the transcription of Caspase12 and Chop, which is vital in endoplasmic reticulum stress (ERS)-mediated apoptosis. These results indicate melatonin protects against epirubicin-induced ovarian damage by reducing ROS-induced ERS. Therefore, melatonin has a therapeutic potential for the protection of ovarian function and preservation of fertility during chemotherapy.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Epirubicina/toxicidade , Melatonina/farmacologia , Ovário/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Peso Corporal/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estradiol/sangue , Feminino , Camundongos , Camundongos Endogâmicos ICR , Ovário/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Progesterona/sangue , Espécies Reativas de Oxigênio/metabolismo , Útero/efeitos dos fármacos , Útero/metabolismo
14.
Dig Endosc ; 32(6): 914-920, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32473036

RESUMO

AIMS: To investigate control measures for COVID-19 pandemic in GIE centers in China. METHODS: This is a retrospective multi-center research, including seven centers. Data collection was from 1 February to 31 March 2020 and the same period in 2019. RESULTS: There were a total of 28 COVID-19 definite cases in these hospitals. Six out of seven GIE centers were arranged to shut down on 1 February, with a mean number of shutdown days of 23.6 ± 5.3. The actual workloads were only 10.3%-62.9% compared to those last year. All centers had a preoperative COVID-19 screening process. Epidemiological questionnaire, temperature taking and QR-code of journey were conducted. Chest CT scan was conducted during the shutdown period and continued in five centers after return to work. Antibody and nucleic acid test were applied in one to three centers. All endoscopists had advanced PPE. Five centers used surgical mask and the rest used N95 mask. Six centers used goggles or face shield. Five centers selected isolation gowns and the rest selected protective suits. The change frequency of these PPE was 4 h. Sterilizing measures were improved in six centers. Five centers utilized ultraviolet and six centers strengthened natural ventilation. Four and six centers used peracetic acid during the period of shutdown and return to work, alone or matched with OPA or acidified water. CONCLUSIONS: Many effective control measures were conducted in GIE centers during the outbreak, including patients' volume limitation, preoperative COVID-19 screening, advanced PPE and disinfection methods.


Assuntos
COVID-19/prevenção & controle , Endoscopia Gastrointestinal , Controle de Infecções/normas , COVID-19/epidemiologia , China/epidemiologia , Humanos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Pandemias , Estudos Retrospectivos , SARS-CoV-2
15.
J Cell Physiol ; 234(10): 17232-17241, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30684287

RESUMO

Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) is a transcriptional coactivator that has been characterized as master regulators of mitochondrial biogenesis. It has been reported that aberrant regulation of PGC-1α is involved in a variety of human cancers. However, whether PGC-1α is involved in the regulation of tumor growth and metastasis in gastric cancer (GC) remains unknown. In the present study, we found that the expression of PGC-1α was upregulated in GC tissues and GC cell lines. Inhibition of PGC-1α inhibited cell viability, migration, and invasion, and promoted cell apoptosis of GC cells. Furthermore, inhibition of PGC-1α downregulated the SNAI1 expression, whereas upregulated microRNA (miR)-128b expression. The expression of SNAI1 was upregulated and the expression of miR-128b was downregulated in GC tissues. We further found that there was a positive correlation between PGC-1α and SNAI1 expression, and a negative correlation between PGC-1α and miR-128b expression or between SNAI1 and miR-128b expression in GC tissues. Moreover, PGC-1α inhibition-induced increased miR-128b expression, and PGC-1α overexpression-induced decreased miR-128b expression were both markedly suppressed by SNAI1 overexpression. In addition, SNAI1 overexpression or miR-128b inhibition partly reversed the effects of PGC-1α inhibition in GC cells. Furthermore, inhibition of PGC-1α suppressed the tumor growth in a nude mouse model, which may be related with the dysregulation of SNAI1 and miR-128b. In conclusion, these data indicate that the PGC-1α/SNAI1/miR-128b axis plays a vital role in GC via regulating cell viability, migration, invasion, and apoptosis.


Assuntos
MicroRNAs/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Fatores de Transcrição da Família Snail/genética , Neoplasias Gástricas/genética , Animais , Apoptose/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Metástase Neoplásica/patologia
16.
Environ Sci Technol ; 53(7): 3610-3619, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30835446

RESUMO

The application of tandem catalysis is rarely investigated in degrading organic pollutants in the environment. Herein, a tandem catalyst on single platinum (Pt) nanoparticles (Pt0 NPs) is prepared for the sequential degradation of formaldehyde (HCHO) to carbon dioxide gas [CO2(g)] at room temperature. The synthesis approach includes coating of uniform Pt NPs on SrBi2Ta2O9 platelets using a photoreduction process, followed by calcination of the sample in the atmosphere to tune partial transformation of Pt0 atoms to Pt2+ ions in the tandem catalyst. The conversion of HCHO to CO2(g) is monitored by in situ Fourier transform infrared spectroscopy, which shows first conversion of HCHO to CO32- ions onto Pt0 active sites and subsequently the conversion of CO32- ions to CO2(g) by neighboring Pt2+ species of the catalyst. The later process with Pt2+ species does not allow CO32- poisoning of the catalyst. The enhanced activity of the prepared tandem catalyst to oxidize HCHO is maintained continuously for 680 min. Comparatively, the catalyst without Pt2+ shows activity for only 40 min. Additionally, the tandem catalyst presented herein performs better than the Pt/titanium dioxide (TiO2) catalyst to degrade HCHO. Overall, the tandem catalyst may be applied to degrade organic pollutants efficiently.


Assuntos
Nanopartículas Metálicas , Platina , Catálise , Domínio Catalítico , Formaldeído , Oxirredução , Temperatura
17.
Angew Chem Int Ed Engl ; 58(14): 4581-4586, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30720233

RESUMO

The synthesis and aqueous self-assembly of a new class of amphiphilic aliphatic polyesters are presented. These AB block polyesters comprise polycaprolactone (hydrophobe) and an alternating polyester from succinic acid and an ether-substituted epoxide (hydrophile). They self-assemble into biodegradable polymersomes capable of entering cells. Their degradation products are bioactive, giving rise to differentiated cellular responses inducing stromal cell proliferation and macrophage apoptosis. Both effects emerge only when the copolymers enter cells as polymersomes and their magnitudes are size dependent.


Assuntos
Poliésteres/metabolismo , Tensoativos/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/química , Fibroblastos/metabolismo , Humanos , Hidrólise , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Estrutura Molecular , Imagem Óptica , Tamanho da Partícula , Poliésteres/química , Poliésteres/farmacologia , Propriedades de Superfície , Tensoativos/química , Tensoativos/farmacologia
18.
Diabetes Metab Res Rev ; 34(4): e2980, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29314572

RESUMO

BACKGROUND: The TCF7L2 (transcription factor 7 like 2) gene is strongly associated with type 2 diabetes risk. However, many people without the TCF7L2 at-risk allele develop T2D. The aim of this study was to investigate altered Tcf7l2 DNA methylation and gene expression caused by high-fat diets (HFDs). METHODS: C57BL/6 mice were fed either an HFD or normal diet for 8 weeks, and intraperitoneal glucose tolerance tests were performed. Pancreatic islets were sorted for bisulfite sequencing polymerase chain reaction to determine DNA methylation status. We cloned the Tcf7l2 promoter, methylated it with methyltransferase, and transfected this construct into MIN-6 cells to confirm the effects of promoter methylation on Tcf7l2 expression. RESULTS: Aberrant methylation at position -165 bp relative to the transcriptional start site of Tcf7l2 was present in mice fed an HFD. Accordingly, expression of Tcf7l2 mRNA and its corresponding protein was lower in the HFD group (P < .05). Methylation of the Tcf7l2 promoter suppressed gene expression in MIN-6 cells. CONCLUSION: An HFD was shown to induce aberrant methylation of the Tcf7l2 promoter in mouse islets, which resulted in diminished gene expression. This study provides an evidence of the association between nutrient consumption and gene expression.


Assuntos
Metilação de DNA , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica , Células Secretoras de Insulina/patologia , Ilhotas Pancreáticas/patologia , Regiões Promotoras Genéticas , Proteína 1 Semelhante ao Fator 7 de Transcrição/genética , Animais , Células Cultivadas , Epigênese Genética , Teste de Tolerância a Glucose , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
19.
J Am Chem Soc ; 138(12): 4120-31, 2016 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-27003333

RESUMO

Controlling polymer composition starting from mixtures of monomers is an important, but rarely achieved, target. Here a single switchable catalyst for both ring-opening polymerization (ROP) of lactones and ring-opening copolymerization (ROCOP) of epoxides, anhydrides, and CO2 is investigated, using both experimental and theoretical methods. Different combinations of four model monomers-ε-caprolactone, cyclohexene oxide, phthalic anhydride, and carbon dioxide-are investigated using a single dizinc catalyst. The catalyst switches between the distinct polymerization cycles and shows high monomer selectivity, resulting in block sequence control and predictable compositions (esters and carbonates) in the polymer chain. The understanding gained of the orthogonal reactivity of monomers, specifically controlled by the nature of the metal-chain end group, opens the way to engineer polymer block sequences.

20.
Environ Sci Technol ; 50(12): 6310-9, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27224055

RESUMO

Environmentally persistent free radicals (EPFRs) are occasionally detected in Superfund sites but the formation of EPFRs induced by polycyclic aromatic hydrocarbons (PAHs) is not well understood. In the present work, the formation of EPFRs on anthracene-contaminated clay minerals was quantitatively monitored via electron paramagnetic resonance (EPR) spectroscopy, and surface/interface-related environmental influential factors were systematically explored. The obtained results suggest that EPFRs are more readily formed on anthracene-contaminated Fe(III)-montmorillonite than in other tested systems. Depending on the reaction condition, more than one type of organic radicals including anthracene-based radical cations with g-factors of 2.0028-2.0030 and oxygenic carbon-centered radicals featured by g-factors of 2.0032-2.0038 were identified. The formed EPFRs are stabilized by their interaction with interlayer surfaces, and such surface-bound EPFRs exhibit slow decay with 1/e-lifetime of 38.46 days. Transformation pathway and possible mechanism are proposed on the basis of experimental results and quantum mechanical simulations. Overall, the formation of EPFRs involves single-electron-transfer from anthracene to Fe(III) initially, followed by H2O addition on formed aromatic radical cation. Because of their potential exposure in soil and atmosphere, such clay surface-associated EPFRs might induce more serious toxicity than PAHs and exerts significant impacts on human health.


Assuntos
Compostos Férricos/química , Radicais Livres/química , Antracenos/química , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Solo/química
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