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1.
J Environ Manage ; 350: 119459, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38000269

RESUMO

High energy consumption is the main obstacle of melting/vitrification technology for the disposal of municipal solid waste incineration fly ash (MSWIFA) for industrial applications. To reduce energy consumption and lower operating costs, oxygen enrichment melting was proposed and studied in this work. This research was conducted in a pilot-scale melting furnace, and three melting conditions were compared and discussed. The results showed that 66% of natural gas was saved and the operating cost was reduced by 55% when oxygen enrichment technology was applied to MSWIFA melting. When coal was used as the fuel with the oxygen enrichment melting technology, the operating cost was even lower at 66.39 dollar/ton of fly ash. Because MSWIFA was a Ca-rich material, the relatively high content of Si and Al in the coal fly ash promoted the formation of vitrificated slag, leading to a reduction in the overall pollution toxicity index (OPTI) of MSWIFA by 99.98%. Meanwhile, SO2, HCl, and secondary fly ash were the main pollutants during MSWIFA melting, and when coal was used as the fuel, the emissions of SO2 and HCl could be reduced and the OPTI of secondary fly ash was suppressed. These results suggested that to obtain the lowest operating cost and reduce secondary pollution during MSWIFA melting, the best option consisted of oxygen enrichment technology with coal as the fuel.


Assuntos
Metais Pesados , Eliminação de Resíduos , Cinza de Carvão , Resíduos Sólidos/análise , Gás Natural , Oxigênio , Incineração , Metais Pesados/análise , Carbono , Material Particulado
2.
Chembiochem ; 24(23): e202300582, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37728423

RESUMO

(R)-ß-piperonyl-γ-butyrolactones are key building blocks for the synthesis of podophyllotoxin, which have demonstrated remarkable potential in cancer treatment. Baeyer-Villiger monooxygenases (BVMOs)-mediated asymmetric oxidation is a green approach to produce chiral lactones. While several BVMOs were able to oxidize the corresponding cyclobutanone, most BVMOs gave the (S) enantiomer while Cyclohexanone monooxygenase (CHMO) from Brevibacterium sp. HCU1 gave (R) enantiomer, but with a low enantioselectivity (75 % ee). In this study, we use a strategy called "focused rational iterative site-specific mutagenesis" (FRISM) at residues ranging from 6 Šfrom substrate. The mutations by using a restricted set of rationally chosen amino acids allow the formation of a small mutant library. By generating and screening less than 60 variants, we achieved a high ee of 96.8 %. Coupled with the cofactor regeneration system, 9.3 mM substrate was converted completely in a 100-mL scale reaction. Therefore, our work reveals a promising synthetic method for (R)-ß-piperonyl-γ-butyrolactone with the highest enantioselectivity, and provides a new opportunity for the chem-enzymatic synthesis of podophyllotoxin.


Assuntos
Oxigenases , Podofilotoxina , Oxigenases/metabolismo , Oxigenases de Função Mista/metabolismo , Oxirredução , Especificidade por Substrato
3.
Artigo em Inglês | MEDLINE | ID: mdl-36884015

RESUMO

A high-level infrared dynamic patterned encoder (IR-DPE) possesses prospective applications for energy-harvesting and information, but a simple and reliable method for fabrication remains challenging. Herein, we first report an IR-DPE with multiple thermal radiation characteristics based on polyaniline (PANI). Specifically, the electron-beam evaporation technique is introduced to obtain the divanadium pentoxide (V2O5) coating, and then the V2O5 film acts as an oxidant to drive in situ polymerization of the PANI film. During the process, we experimentally explore the relationship between the thickness of V2O5 and the emissivity of PANI to obtain up to six emissivity levels and achieve the IR pattern integrated into multiple thermal radiation characteristics. The device shows multiple thermal radiation characteristics at the oxidized state, realizing a pattern visible with the IR camera and the same thermal radiation properties at the reduced state, leading to the pattern concealed in the IR regime. In addition, the highest emissivity tunability of the device is to be tuned from 0.40 to 0.82 (Δε = 0.42) at 2.5-25 µm. Meanwhile, the device exhibits a maximum temperature control of up to 5.9 °C. The results show the enormous potential of IR-DPEs for IR information transfer and thermal management.

4.
Front Cardiovasc Med ; 9: 1012095, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36531702

RESUMO

Aims: To investigate the risk factors, clinical features, and prognostic factors of patients with premature acute myocardial infarction (AMI). Materials and methods: A retrospective cohort study of patients with AMI included in data from the West China Hospital of Sichuan University from 2011 to 2019 was divided into premature AMI (aged < 55 years in men and < 65 years in women) and non-premature AMI. Patients' demographics, laboratory tests, Electrocardiography (ECG), cardiac ultrasound, and coronary angiography reports were collected. All-cause death after incident premature MI was enumerated as the primary endpoint. Results: Among all 8,942 AMI cases, 2,513 were premature AMI (79.8% men). Compared to the non-premature AMI group, risk factors such as smoking, dyslipidemia, overweight, obesity, and a family history of coronary heart disease (CHD) were more prevalent in the premature AMI group. The cumulative survival rate of patients in the premature AMI group was significantly better than the non-premature AMI group during a mean follow-up of 4.6 years (HR = 0.27, 95% CI 0.22-0.32, p < 0.001). Low left ventricular ejection fraction (LVEF) (Adjusted HR 3.00, 95% CI 1.85-4.88, P < 0.001), peak N-terminal pro-B-type natriuretic peptide (NT-proBNP) level (Adjusted HR 1.34, 95% CI 1.18-1.52, P < 0.001) and the occurrence of in-hospital major adverse cardiovascular and cerebrovascular events (MACCEs) (Adjusted HR 2.36, 95% CI 1.45-3.85, P = 0.001) were predictors of poor prognosis in premature AMI patients. Conclusion: AMI in young patients is associated with unhealthy lifestyles such as smoking, dyslipidemia, and obesity. Low LVEF, elevated NT-proBNP peak level, and the occurrence of in-hospital MACCEs were predictors of poor prognosis in premature AMI patients.

5.
Viruses ; 13(10)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34696377

RESUMO

To evaluate whether uterine injury caused by hepatitis E virus (HEV) infection is responsible for adverse pregnancy outcomes. HEV-infected female BALB/c mice were coupled with healthy male BALB/c mice at 0, 7, 14, 21, and 91 dpi to explore the uterine injury caused by HEV infection. Mice were euthanized after 10 days of copulation, and uteruses were collected for HEV RNA and antigen detection and histopathological analysis. Inflammatory responses; apoptosis; and estrogen receptor ɑ (ER-ɑ), endomethal antibody (ERAb), cytokeratin-7 (CK7), vimentin (VIM), and vascular endothelial growth factor (VEGF) expression levels were evaluated. After 10 days of copulation, miscarriage and nonpregnancy, as well as enlarged uteruses filled with inflammatory cytokines, were found in HEV-infected mice. HEV RNA and antigens were detected in the sera and uteruses of HEV-infected mice. Significant endometrial thickness (EMT) thinning, severe inflammatory responses, and aggravated apoptosis in the uteruses of HEV-infected mice that experienced miscarriage might contribute to adverse pregnancy outcomes. Furthermore, significantly suppressed ER-ɑ expression and increased ERAb, CK7, VIM, and VEGF expression levels were found in the uteruses of HEV-infected mice that had miscarried. However, uterine damage recovered after complete HEV clearance, and impaired fertility was improved. EMT injury, severe inflammatory responses, and aggravated apoptosis in the uterus caused by HEV infection are responsible for poor pregnancy outcomes.


Assuntos
Genótipo , Vírus da Hepatite E/genética , Vírus da Hepatite E/patogenicidade , Hepatite E/complicações , Útero/lesões , Útero/virologia , Aborto Espontâneo , Animais , Modelos Animais de Doenças , Feminino , Anticorpos Anti-Hepatite/imunologia , Hepatite E/virologia , Vírus da Hepatite E/classificação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Resultado da Gravidez , Anormalidades Urogenitais/virologia , Útero/anormalidades , Útero/patologia , Eliminação de Partículas Virais
6.
J Med Virol ; 93(11): 6267-6277, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34076903

RESUMO

Hepatitis E virus (HEV) is the major pathogen of viral hepatitis. However, the understanding of the HEV life cycle is limited. In the present study, cells were separately infected with nonenveloped HEV (derived from feces or bile) or quasi-enveloped HEV (derived from the cell culture after serial passages, eHEV) and observed by confocal fluorescence microscopy to investigate the life cycle of HEV. HEV finished its binding and entry into host cells at first 6 h postinoculation (hpi). Cells inoculated with eHEV showed less infectivity than cells inoculated with nonenveloped HEV. Newly synthesized progeny virions were released into the supernatant of cell cultures from 48 hpi. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis results showed that the supernatant's progeny viruses were infectious even after five serial passages. These results show the significant difference between nonenveloped HEV and eHEV, which will provide novel insights into the HEV replication cycle. The efficient cell culture of HEV will promote the development of anti-HEV drugs and vaccines.


Assuntos
Vírus da Hepatite E/fisiologia , Replicação Viral , Células A549 , Carcinoma Hepatocelular , Linhagem Celular , Linhagem Celular Tumoral , Hepatite E/virologia , Vírus da Hepatite E/classificação , Humanos , Neoplasias Hepáticas , Microscopia de Fluorescência/métodos , Envelope Viral , Vírion/fisiologia
7.
J Med Virol ; 93(6): 3769-3778, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33128390

RESUMO

Hepatitis E virus (HEV) infection has become a global concern with high mortality rates among pregnant women, especially those in their third trimester of pregnancy. Estrogen plays an important role in mediating the body, regulating physiological and pathological processes. Estrogen is activated by binding to estrogen receptors (ERs) and mediates rapid signaling events by pathways that involve transmembrane ERs. Our previous study had confirmed that high estrogen levels during pregnancy are associated with high HEV titers. However, the association between HEV infection and estrogen signaling pathways remains unclear. In the present study, the regulation of estrogen signaling pathways by HEV infection was evaluated. Results demonstrated that HEV infection significantly inhibits the cAMP-PKA-CREB and PI3K-AKT-mTOR signaling pathways, but is independent of the Ras-Raf-MEK-ERK signaling pathway. In summary, the increasing estrogen levels and highly activated ERα during pregnancy aggravates HEV replication. The exacerbation of HEV replication, in turn, inhibits ERα expression and suppresses both cAMP-PKA-CREB and PI3K-AKT-mTOR signaling pathways.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/antagonistas & inibidores , Estrogênios/metabolismo , Vírus da Hepatite E/patogenicidade , Hepatite E/fisiopatologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transdução de Sinais , Serina-Treonina Quinases TOR/antagonistas & inibidores , Células A549 , Estrogênios/genética , Feminino , Humanos , Gravidez , Proteínas Proto-Oncogênicas c-akt/metabolismo
8.
Fish Physiol Biochem ; 36(2): 157-64, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20467857

RESUMO

Vitellogenins (Vtgs), the precursors for the yolk proteins, are very important for the embryonic development of teleosts, and have also been studied extensively as biomarkers for environmental estrogenic mimics. The cDNA for a Vtg was isolated from the liver of the female white cloud mountain minnow (Tanichthys albonubes) by 3'- and 5'-RACE methods. It is 4,171 bp in full length, and encodes a putative protein of 1,326 amino acids. This putative Vtg, designated as wcmmVtg, contains complete portions of LVI and PV, but lacks the C-terminal half of LVII and thus belongs to type I vitellogenin. In addition to the liver of the female fish, wcmmVtg was also shown to be expressed in the ovary. During ovarian development, the mRNA expression of wcmmVtg in both the liver and ovary was continuously increased from the previtellogenic to late vitellogenic stages, but then decreased significantly at post-spawning stage. In the male fish, expression of wcmmVtg mRNA was induced in the liver by treatment with E2 (10 and 100 ng/l) for 14 days. These results suggest that the Vtg originated from the ovary of the white cloud mountain minnow may also contribute to the accumulation of yolk proteins during oocyte growth, and that the male white cloud mountain minnow is sensitive to the estrogenic treatment in terms of Vtg mRNA expression, which could also be applied to monitor the environmental estrogenic mimics.


Assuntos
Cyprinidae/genética , Proteínas de Peixes/genética , Vitelogeninas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Cyprinidae/crescimento & desenvolvimento , Cyprinidae/metabolismo , Primers do DNA/genética , Estradiol/farmacologia , Feminino , Expressão Gênica/efeitos dos fármacos , Masculino , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Distribuição Tecidual
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