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1.
J Environ Manage ; 304: 114170, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34864419

RESUMEN

Oil-based drilling cuttings (OBDC) produced from shale gas development is a hazardous waste that have high calorific values and should be disposed of properly. Burning bricks with OBDC is a promising co-disposal method; however, organic pollutants emitted during this process have not received sufficient attention. In this study, the composition and combustion characteristics of OBDC were determined, and the emissions of typical organic pollutants when burning bricks with the addition of OBDC were investigated; these included benzene series compounds (BTEXs), non-methane total hydrocarbons (NMHC), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs). The results showed that OBDC comprised large amounts of alkanes and aromatic hydrocarbons, and combusted mainly in the temperature range of 145-450 °C with an ignition temperature of 145 °C. The co-processing 10% OBDC increased the concentrations of toluene, NMHC, and PAHs in the flue gases by ∼1000%, ∼500%, and 200%, respectively, compared to the control experiment; however, their emission concentrations were within the limits set by the Integrated emission standards of air pollutants of Chongqing. It is worth noting that 26.443 ng/Nm3 PCDD/Fs with a total toxicity of 0.709 ng I-TEQ/Nm3 was generated from the co-processing 10% OBDC, which was ascribed to the high content of chlorine and aromatic hydrocarbons in the OBDC-promoted PCDD/Fs formed during the burning and cooling processes. Though PCDD/Fs in flue gas exceeded the 0.5 ng I-TEQ/Nm3 limit prescribed in the Pollution control standard for hazardous wastes incineration of China, the realistic emission of PCDD/Fs is expected to meet with this emission limit after desulfurization treatment as PCDD/Fs can be absorbed by gypsum. It is recommended that a lower amount of OBDC is added to reduce PCDD/F formation at the source and to take more efficient air pollution control system in order to reach a stricter emission limit of 0.1 ng I-TEQ/Nm3 in EU and USA. Cycling flue gas may also be an effective method to reduce other organic pollutants. Under these conditions, co-processing OBDC in brick kilns can be achieved without serious environmental pollution, making it a potential method for disposal and utilization.


Asunto(s)
Contaminantes Atmosféricos , Benzofuranos , Dibenzodioxinas Policloradas , Hidrocarburos Policíclicos Aromáticos , Contaminantes Atmosféricos/análisis , Benzofuranos/análisis , Dibenzofuranos , Dibenzofuranos Policlorados/análisis , Monitoreo del Ambiente , Incineración , Metano , Dibenzodioxinas Policloradas/análisis
2.
BMC Infect Dis ; 20(1): 537, 2020 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-32703176

RESUMEN

BACKGROUND: Twelve students experienced symptoms of acute respiratory infection (ARI) at a training base in Beijing from August 26 to August 30, 2015. We investigated the cause of this ARI outbreak. METHODS: In partnership with the local center for disease control, we collected a total of twelve pharyngeal swab specimens as well as demographic information for the affected patients. We used multiplex real-time PCR to screen for sixteen common respiratory viruses in these samples. To isolate HAdV, we inoculated Hep-2 cells with the human adenovirus (HAdV)-positive samples and then carried out sequencing and phylogenetic analysis of the hexon, fiber, and penton genes of the isolated adenoviruses. In addition, we analyzed the entire genome of one strain isolated from the index case to identify single-nucleotide substitutions. RESULTS: We identified ten HAdV-positive students using multiplex real-time PCR. None of the students were co-infected with other viruses. We successfully isolated seven HAdV strains from the pharyngeal swab specimens. The coding sequences of the hexon, fiber, and penton genes of these seven HAdV strains were identical, suggesting that they represented seven strains from a single virus clone. One HAdV isolate obtained from the index case, BJDX-01-2015, was selected for whole genome analysis. From this isolate, we obtained a 34,774-nucleotide sequence. The genome of BJDX-01-2015 clustered with HAdV-B55 in phylogenetic analyses and had 99.97% identity with human adenovirus 55 isolate HAdV-B/CHN/BJ01/2011/55 (GenBank accession no. JX491639). CONCLUSIONS: We identified HAdV-B55 as the strain associated with the August 2015 ARI outbreak at a training base in Beijing. This was the first reported outbreak in Beijing due to HAdV-B55. Continuous surveillance of respiratory adenoviruses is urgently needed to understand the epidemiological and evolutionary features of HAdV-B55, and an epidemiological modeling approach may provide further insights into this emerging public health threat. Furthermore, the clinical laboratory data from this outbreak provides important reference for the clinical diagnosis and may ultimately aid in informing the development of strategies to control and prevent respiratory tract infections caused by HAdV-B55.


Asunto(s)
Infecciones por Adenovirus Humanos/epidemiología , Adenovirus Humanos/genética , Brotes de Enfermedades , Infecciones del Sistema Respiratorio/epidemiología , Infecciones por Adenovirus Humanos/virología , Adolescente , Beijing/epidemiología , Humanos , Incidencia , Masculino , Reacción en Cadena de la Polimerasa Multiplex , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Infecciones del Sistema Respiratorio/virología , Estudiantes , Secuenciación Completa del Genoma
3.
Chin J Cancer Res ; 26(1): 112-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24653633

RESUMEN

OBJECTIVE: To compare radiofrequency ablation (RFA) or microwave ablation (MWA) and transcatheter arterial chemoembolization (TACE) with RFA or MWA monotherapy in hepatocellular carcinoma (HCC). METHODS: A prospective, randomized, controlled trial was conducted on 94 patients with HCC ≤7 cm at a single tertiary referral center from June 2008 to June 2010 at the Department of Hepatobiliary Surgery, the Second Affiliated Hospital of Southeast University. The patients were randomly assigned into the TACE-RFA or TACE-MWA (combined treatment group) and the RFA-alone or MWA-alone groups (control group). The primary end point was overall survival. The secondary end point was recurrence-free survival, and the tertiary end point was adverse effects. RESULTS: Until the time of censor, 17 patients in the TACE-RFA or TACE-MWA group had died. The median follow-up time of the patients who were still alive for the TACE-RFA or TACE-MWA group was 47.5±11.3 months (range, 29 to 62 months). The 1-, 3- and 5-year overall survival for the TACE-RFA or TACE-MWA group was 93.6%, 68.1% and 61.7%, respectively. Twenty-five patients in the RFA or MWA group had died. The median follow-up time of the patients who were still alive for the RFA or MWA group was 47.0±12.9 months (range, 28 to 62 months). The 1-, 3- and 5-year overall survival for the RFA or MWA group was 85.1%, 59.6% and 44.7%, respectively. The patients in the TACE-RFA or TACE-MWA group had better overall survival than the RFA or MWA group [hazard ratio (HR), 0.526; 95% confidence interval (95% CI), 0.334-0.823; P=0.002], and showed better recurrence-free survival than the RFA or MWA group (HR, 0.582; 95% CI, 0.368-0.895; P=0.008). CONCLUSIONS: RFA or MWA combined with TACE in the treatment of HCC ≤7 cm was superior to RFA or MWA alone in improving survival by reducing arterial and portal blood flow due to TACE with iodized oil before RFA.

4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 47(5): 420-6, 2013 May.
Artículo en Chino | MEDLINE | ID: mdl-23958124

RESUMEN

OBJECTIVE: To explore the characteristics of the whole genome of the influenza H1N1 virus of the mild and severe cases in Beijing. METHODS: A total of 21 samples of throat swabs were collected from surveillance-designated hospitals between June and December in 2009, including 10 severe cases (4 death cases) and 11 mild cases. RNA of the virus were extracted,and the amplified primers of the whole genome were designed.Reverse transcription and PCR were performed to the RNA and then the PCR product was sequenced by software to analyze the evolution of the viral genes and the variation of the amino acids. RESULTS: Compared with the reference vaccine strain A/California/07/2009 (H1N1), the genetic nucleotide homology in the eight segments of the pandemic H1N1 virus in Beijing in 2009 was higher than 99%, without significant variation. Among them,the genetic distance of hemagglutinin (HA), neuraminidase (NA) and nucleoprotein (NP) was comparatively far, separately 0.0050, 0.0040 and 0.0040.The gene of HA, P83S, the gene of NA, N248D, the gene of polymerase (PA), P224S and the gene of NP, V100I and L122Q were found to mutate in all the samples. Genes of HA, NA, NP, PA, PB 2 and nonstructural protein (NS1) in severe cases showed obviously clustered evolution. The mutation of gene S128P and S203T of HA, gene R269R and D547E of PA, gene T588I of PB 2 and gene I123V of NS mainly happened in severe cases, separately counting 6, 9, 6, 7, 9 and 6 cases. The relevance between the mutation happened in S203T of HA, R269K and D547E of PA and the severeness of the cases showed statistical significance (P < 0.05). The mutations of HA gene were mainly on the Ca and Cb antigene domains. No drug resistant mutation was found on NA gene but happened on matrix protein 2 (M2 gene). None of the mutations were found on the virulence related genes. CONCLUSION: A high homology was found between the pandemic H1N1 virus in Beijing in 2009 and the reference vaccine strain A/California/07/2009(H1N1). Mutational sites related with the severe and fatal cases were found, but not the virulence related mutation.


Asunto(s)
Genoma Viral , Subtipo H1N1 del Virus de la Influenza A/genética , Gripe Humana/virología , Secuencia de Bases , China/epidemiología , Genes Virales , Variación Genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Humanos , Gripe Humana/epidemiología , Neuraminidasa/genética , Proteínas de la Nucleocápside , Proteínas de Unión al ARN/genética , Proteínas del Núcleo Viral/genética
5.
Int Ophthalmol ; 27(4): 235-9, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17464452

RESUMEN

BACKGROUND: It is well known that mast cells (MC) are involved in fibrosis and many forms of chronic inflammation. Chronic inflammatory cells infiltration and fibrosis in various orbital tissues are the main histopathologic features in patients with idiopathic orbital inflammatory pseudotumor (IOIP). Whether MC is involved in the course of chronic inflammatory conditions of IOIP is not yet clear. We sought to investigate the distribution of MCs in samples of IOIP and to explore the possible role of MC in the course of its pathegenesis. METHODS: Immunohistochemistry with tryptase monoclonal antibody (a specific mast-cell surface marker) was used in 53 different subtypes of IOIP specimens including 19 of the lymphocyte infiltrative type, 22 of the fibrotic type, 12 of the mixed type and 4 specimens of normal orbital tissue. The number of positive stained MC was counted by light microscopy. The differences of the number of MC between various subtypes of IOIP were analyzed. RESULTS: The average number of positive stained MC in the normal control group was 33.33 +/- 4.72 /mm(3), whereas the average numbers of positive stained MC in the lymphocyte infiltrative subtype group, the mixed subtype group and the fibrotic subtype group were 306.35 +/- 55.81 /mm(3), 662.93 +/- 115.28 /mm(3) and 813.44 +/- 146.56 /mm(3), respectively. Compared with the normal control, the number of MC increased significantly in all three subtypes of IOIP samples (P < 0.01). The number of MC in fibrotic subtype IOIP was the largest, followed by mixed subtype IOIP, and the lymphocyte infiltrative subtype IOIP (P < 0.05). The MC were distributed mainly around small vessels and in collagen fibers. CONCLUSION: Mast cells may play an underappreciated role in the fibrosis of IOIP.


Asunto(s)
Inmunohistoquímica/métodos , Mastocitos/patología , Seudotumor Orbitario/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales , Recuento de Células , Niño , Diagnóstico Diferencial , Femenino , Humanos , Linfocitos/patología , Masculino , Persona de Mediana Edad , Seudotumor Orbitario/etiología , Estudios Retrospectivos , Triptasas/inmunología
6.
Yan Ke Xue Bao ; 19(1): 54-9, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12852089

RESUMEN

PURPOSE: To study the changes of telomerase activity and cytotoxic effects by Cisplatin; cis-dichlorodiamine platinum (CDDP) in cultured human choroidal melanoma. MATERIAL AND METHODS: The primary cultured human choroidal melanoma cells were cultured in the presence and absence of CDDP with different concentration and time respectively. The toxic effects were evaluated by MTT and the level of telomerase was detected by PCR-ELISA assay. And the relationship between telomerase activity and cytotoxic effects were analyzed by a correlation analysis. RESULTS: Following the increase of the concentration and the time of CDDP, gradually repressed telomerase activity was detected in cultured cells. Meanwhile, the restrain rate of the cells increased. The telomerase activity at 24 h and 1 microgram/ml was repressed significantly compared with the control cells. However, the appearance of cell death lagged behind the decreasing of telomerase. CONCLUSIONS: CDDP is an effective telomerase inhibitor in cultured choroidal melanoma cells of human eyes, which presents concentration and time dependency and can cause the death of cultured cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias de la Coroides/patología , Cisplatino/farmacología , Melanoma/patología , Telomerasa/metabolismo , Adulto , Antineoplásicos/farmacología , Muerte Celular/efectos de los fármacos , Neoplasias de la Coroides/enzimología , Femenino , Humanos , Masculino , Melanoma/enzimología , Persona de Mediana Edad , Telomerasa/antagonistas & inhibidores , Células Tumorales Cultivadas
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