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1.
Sci Total Environ ; 912: 169077, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38056672

RESUMO

The aim of this study is to propose a desulfurized rubber powder / styrene butadiene styrene (DRP/SBS) composite modified asphalt technology by combining the advantages of DRP and SBS. This reduces the production cost of modified asphalt and improves the performance of asphalt. In this paper, orthogonal tests were used to optimize preparation process parameters of DRP/SBS composite modified asphalt. And the physicochemical properties, modification mechanism of composite modified asphalt had been thoroughly studied. Subsequently, the results showed that the optimum content of DRP and SBS modifiers are 25 % and 2 %, respectively. The suitable preparation process is to add SBS first, then DRP, while shearing at 5000 r/min for 50 min. In addition, DRP/SBS composite modified asphalt has better high-temperature performance, viscosity-temperature characteristics, aging resistance, and storage stability. Meanwhile, the storage stability of the composite modified asphalt was verified by fluorescence microscopy test. Through the Fourier transform infrared spectroscopy test, it was observed that the composite modified asphalt modification process is a compatible and stable modification of physical and chemical coexistence. Overall, the composite modification method achieves recycling of waste tires while improving pavement performance, thus promoting the sustainability of pavement.

2.
Cancer Biol Med ; 20(11)2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-38018033

RESUMO

Cancer is the leading cause of death worldwide. Early detection of cancer can lower the mortality of all types of cancer; however, effective early-detection biomarkers are lacking for most types of cancers. DNA methylation has always been a major target of interest because DNA methylation usually occurs before other detectable genetic changes. While investigating the common features of cancer using a novel guide positioning sequencing for DNA methylation, a series of universal cancer only markers (UCOMs) have emerged as strong candidates for effective and accurate early detection of cancer. While the clinical value of current cancer biomarkers is diminished by low sensitivity and/or low specificity, the unique characteristics of UCOMs ensure clinically meaningful results. Validation of the clinical potential of UCOMs in lung, cervical, endometrial, and urothelial cancers further supports the application of UCOMs in multiple cancer types and various clinical scenarios. In fact, the applications of UCOMs are currently under active investigation with further evaluation in the early detection of cancer, auxiliary diagnosis, treatment efficacy, and recurrence monitoring. The molecular mechanisms by which UCOMs detect cancers are the next important topics to be investigated. The application of UCOMs in real-world scenarios also requires implementation and refinement.


Assuntos
Neoplasias , Humanos , Neoplasias/diagnóstico , Neoplasias/genética , Metilação de DNA , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Pescoço
3.
Environ Sci Pollut Res Int ; 30(15): 44251-44265, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36683109

RESUMO

Traditional asphalt rubber (AR) has a high viscosity and poor fluidity, which makes its construction very difficult. Reducing viscosity has been identified as one of the effective way of solving these problems. Meanwhile, the mass production and improper discharge of waste engine oil (WEO) have a serious impact on the ecological environment, and its rational reuse needs to be addressed. In this paper, molecular models of AR and WEO-modified asphalt rubber (WEOMAR) was established by molecular dynamics (MD) simulations. The influence of WEO on asphalt component's behavior was studied by radial distribution function (RDF) and diffusion coefficient (D). Then, the microscopic mechanism of viscosity reduction was evaluated. Furthermore, the viscosity reduction behavior of WEO in AR was analyzed and verified by basic properties and low field nuclear magnetic resonance (LF-NMR) laboratory tests. The results showed that the RDF peak value of rubber molecules in WEOMAR is 14.07 higher than that of AR, at r = 2.16 Å. The D of saturated and aromatic components in WEOMAR obviously increased by 140% and 67.9%, respectively. The light component molecules increased after adding WEO into AR. The rubber molecule reduces the contact with asphaltene and resin, and the viscosity of AR is significantly reduced, which is confirmed by the macro tests.


Assuntos
Simulação de Dinâmica Molecular , Borracha , Viscosidade , Hidrocarbonetos
4.
Environ Sci Pollut Res Int ; 29(60): 90463-90478, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35871198

RESUMO

The comprehensive utilization of waste cooking oil (WCO) and waste engine oil (WEO) is of great significance to build a sustainable society because recycling WCO and WEO to develop a rejuvenator for asphalt pavement not only aids the reduction of environmental pollution, but also brings about significant benefits to the Earth's sustainable development. With a clear aim to contribute to a more efficient reuse of the waste oils and recycled asphalt mixtures, this paper develops a high-efficiency compound rejuvenator and determines the optimal combination of its main constituents (WCO and WEO) through orthogonal tests. Furthermore, the performance of the rejuvenator is verified by means of the four-fraction test and the traditional asphalt performance tests (penetration, ductility, softening point). These tests confirm the regeneration efficiency of the compound rejuvenator, and the optimum dosage of the compound rejuvenator is found of 7%. Subsequently, the mechanism of the compound rejuvenator in aged asphalt is examined, and following the application of the compound rejuvenator, it was concluded that the reclaimed asphalt pavement (RAP) could be maximized by 45%. Consequentially, the results of this research promote the recycling of WEO, WCO, and waste asphalt pavement materials, ultimately advocating the sustainability of pavement construction.


Assuntos
Óleos , Desenvolvimento Sustentável , Culinária
5.
J Periodontal Res ; 55(5): 581-593, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32583879

RESUMO

Periodontal disease (PD), as a chronic bacterial infection, might cause cardiovascular and some other systemic diseases, with recent studies reporting that it exhibits some connection with lung cancer. While studies have shown that poor oral health might increase the risk of lung cancer, the veracity of these reports is questionable. Therefore, this meta-analysis was undertaken to investigate the association between PD and the risk of lung cancer. A search was run in PubMed, EMBASE, MEDLINE, CENTRAL, and ClinicalTrials.gov databases up to January 1, 2020. Cohort and case-control studies investigating the correlation between PD and lung cancer were included. Eligibility assessment and data extraction were conducted independently, and a meta-analysis was performed to synthesize the data. The association between PD, edentulism, and lung cancer was measured by the adjusted hazard ratios (HRs) or odds ratios (ORs) and their 95% confidence intervals (CIs) provided in articles. We employed appropriate effect model in terms of I2 (a fixed-effect model for PD and a random-effect model for edentulism) to obtain summary effect estimates. Statistical heterogeneity was investigated by chi-square test and I2 statistics. Newcastle-Ottawa Scale (NOS) was used to assess the quality of their method. Six cohort studies (eight references) and two case-control studies, assessed as high-quality, involving 167 256 participants, were included in the review. The summary estimates based on adjusted data showed an association between PD and a significant risk of lung cancer both in cohort studies (HR = 1.40, 95% CI = 1.25-1.58; I2  = 8.7%) and case-control studies (OR = 1.51, 95% CI = 1.16-1.98; I2  = 36.5%). Similar features were found in the sensitivity analysis and subgroups for six cohort studies, of male only (HR = 1.36, 95% CI = 1.15-2.60), setting the lung cancer incidence as endpoint (HR = 1.39, 95% CI = 1.24-1.57; I2  = 23.9%), and adjusting alcohol for multifactorial HR (HR = 1.38, 95% CI = 1.21-1.57; I2  = 39.9%). The summary HR for edentulism was 1.93 (95% CI = 1.05-3.57; I2  = 55.3%). No obvious publication bias was detected. This systematic review and meta-analysis demonstrated a significant association between PD and the incidence of lung cancer. Further observational studies are required by using standardized measurements to assess the periodontal status and by eliminating confounding factors, such as alcohol and diabetes, to verify such a relationship.


Assuntos
Neoplasias Pulmonares , Doenças Periodontais , Estudos de Casos e Controles , Estudos de Coortes , Humanos , Incidência , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia , Masculino , Doenças Periodontais/complicações , Doenças Periodontais/epidemiologia
6.
J Am Chem Soc ; 141(23): 9408-9414, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31117669

RESUMO

Soft porous crystals (SPCs) that exhibit stimuli-responsive dynamic sorption behavior are attracting interest for gas storage/separation applications. However, the design and synthesis of SPCs is challenging. Herein, we report a new type of SPC based on a [2 + 3] imide-based organic cage (NKPOC-1) and find that it exhibits guest-induced breathing behavior. Various gases were found to induce activated NKPOC-1 crystals to reversibly switch from a "closed" nonporous phase (α) to two porous "open" phases (ß and γ). The net effect is gate-opening behavior induced by CO2 and C3 hydrocarbons. Interestingly, NKPOC-1-α selectively adsorbs propyne over propylene and propane under ambient conditions. Thus, NKPOC-1-α has the potential to separate binary and ternary C3 hydrocarbon mixtures, and the performance was subsequently verified by fixed bed column breakthrough experiments. In addition, molecular dynamics calculations and in situ X-ray diffraction experiments indicate that the gate-opening effect is accompanied by reversible structural transformations. The adsorption energies from molecular dynamics simulations aid are consistent with the experimentally observed selective adsorption phenomena. The understanding gained from this study of NKPOC-1 supports the further development of SPCs for applications in gas separation/storage because SPCs do not inherently suffer from the recyclability problems often encountered with rigid materials.

7.
Pharmacogn Mag ; 12(45): 25-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27019558

RESUMO

BACKGROUND: Luffa echinata Roxb. (LER) (Cucurbitaceae) showed tremendous medicinal importance and are being used for the treatment of different ailments. OBJECTIVE: In this study, the antiproliferative properties and cell death mechanism induced by the extract of the fruits of LER were investigated. MATERIALS AND METHODS: MTT and LDH assay were used to test the antiproliferative and cytotoxicity of LER extract, respectively. The intracellular ROS were measured by a fluorometric assay. The expression of several apoptotic-related proteins in SW-480 cells treated by LER was evaluated by Western blot analysis. RESULTS: The methanolic extract of LER fruits inhibited the proliferation of human colon cancer cells (SW-480) in both dose- and time-dependent manners. The LER-treated cells showed obvious characteristics of cell apoptosis, including cell shrinkage, destruction of the monolayer, and condensed chromatin. In addition, treatments of various concentrations of LER extracts caused the release of lactate dehydrogenase as a dose-dependent manner via stimulation of the intracellular metabolic system. LER induced apoptosis, DNA fragmentation, and cellular ROS accumulation in SW-480 cells. Treatment of LER on SW-480 cells promoted the expression of caspases, Bax, Bad, and p53 proteins and decreased the levels of Bcl-2 and Bcl-XL. CONCLUSIONS: These results indicated that treatment with LER-induced cell death in mitochondrial apoptosis pathway by regulating pro-apoptotic proteins via the up regulation of the p53 protein. These findings highlight the potentials of LER in the treatment of human colon cancer. SUMMARY: LER induced apoptosis, DNA fragmentation, and cellular ROS accumulation in SW-480 cells. Treatment of LER on SW-480 cells promoted the expression of caspases, Bax, Bad, and p53 proteins and decreased the levels of Bcl-2 and Bcl-XL.

8.
J Biomed Sci ; 16: 33, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19292890

RESUMO

Developmentally regulated endothelial cell locus-1 (Del1) is an embryonic angiogenic factor expressed in early embryonic endothelial cells, but recently has been found to be expressed in some forms of cancers including colon and breast cancers, and melanoma, and human cancer cell lines. Overexpression of Del1 accelerates tumor growth by enhancing vascular formation, implying Del1 may be a potential target for anti-angiogenic cancer therapy. The study aims to investigate whether downregulation of Del1 could inhibit the growth of tumors established in nude Balb/c mice by subcutaneous implantation of human LS-174T colon cancer cells. The shRNA expression vectors targeting human Del1, and vascular endothelial growth factor (VEGF) were constructed. Gene transfection of Del1-shRNA downregulated expression of Del1 in LS-174T cells in vivo and in vitro, but did not alter the proliferative or survival properties of cells in vitro. Gene transfection of VEGF-shRNA downregulated expression of both VEGF and Del1 in LS-174T cells in vivo and in vitro. Both Del1-shRNA and VEGF-shRNA gene therapies exhibited anti-tumor activities and they also showed a synergistic effect in suppressing growth of colon tumors by anti-angiogenesis and anti-proliferation. Although further investigation to clarify the mechanisms explaining the role of Del1 in tumor growth, and the interaction between VEGF and Del1, is required, the results indicate that downregulation of Del1 presents a potent therapeutic strategy to combat colon cancer.


Assuntos
Proteínas de Transporte/biossíntese , Neoplasias do Colo/metabolismo , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Animais , Proteínas de Ligação ao Cálcio , Proteínas de Transporte/genética , Moléculas de Adesão Celular , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Terapia Genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/genética , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Neovascularização Patológica/terapia , Transfecção , Fator A de Crescimento do Endotélio Vascular/biossíntese , Fator A de Crescimento do Endotélio Vascular/genética
9.
Ann Epidemiol ; 18(6): 484-91, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18440825

RESUMO

PURPOSE: To examine age-related effects of smoking on lung cancer mortality in a large population-based case-control study that was incorporated into a nationwide retrospective survey of mortality in China. METHODS: Two data sets were pooled for this analysis: national mortality survey data and data from a nationwide case-control comparison. These pooled data were used to calculate age-specific lung cancer death rates by smoking status and expected years of lost life expectancy for each smoking-associated death. RESULTS: There was a significant excess of deaths (54% of urban deaths, 51% of rural deaths) at 35 to 69 years of age among male smokers and the average loss of life expectancy per smoking-associated death at these ages was 18.3 years. For women ages 35 to 69 years of age, 29% and 11% excess lung cancer mortality was observed in urban and rural smokers, respectively, with an average loss of life expectancy per smoking-associated death of 21.3 years. CONCLUSIONS: Tobacco smoking was associated with a large number of deaths from lung cancer. Utilizing information from a population-based retrospective mortality survey for conducting an analytic epidemiological study of main determinants of disease is feasible and can generate important results.


Assuntos
Neoplasias Pulmonares/mortalidade , Fumar/efeitos adversos , Adulto , Fatores Etários , Idoso , Estudos de Casos e Controles , China/epidemiologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores Sexuais , Fumar/mortalidade
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