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1.
Huan Jing Ke Xue ; 40(10): 4310-4318, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854797

RESUMO

Based on observational data for pollutants and meteorology, this study analyzed the pollution episode that occurred during Dec 17th to 23th in 2018 in Zhaoqing, Guangdong Province, China. Using the source apportionment model CMAQ-ISAM and the hybrid receptor model, the regional contributions to air pollution were examined. The results showed that low-pressure conditions had an adverse effect on the diffusion of pollutants during this pollution episode in Zhaoqing. Prior to the pollution episode, pollutants were mainly derived from Zhaoqing and Qingyuan, accounting for 19.2% and 10.7% of pollutants, respectively. As well as pollutants from Guangdong Province, long-distance transport of pollutants from Jiangxi, Hunan, Hubei, and Shaanxi accounted for approximately 64.5% of the total during the non-pollution period. During the polluted episode, major cities in Pearl River Delta and the eastern part of Guangdong Province contributed more pollutants as a surface high-pressure field moved southward. Zhaoqing, Foshan, Dongguan, Guangzhou, and Huizhou contributed 25.5%, 14.8%, 9.8%, 9.5%, and 5.3% of the pollutants, respectively. Cities in the eastern part of Guangdong Province including Heyuan, Meizhou, Shanwei, Jieyang, Shantou, and Chaozhou contributed 13.7% of the total pollutants. In addition, pollutants from Fujian, Jiangxi, and the Yangtze River Delta accounted for approximately 32.9%. Furthermore, pollutants transported under marine influences were one of the main causes of this pollution episode in Zhaoqing.

2.
Huan Jing Ke Xue ; 39(9): 3995-4001, 2018 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-30188039

RESUMO

An emission inventory of atmospheric pollutants from crop residue burning in Guangdong for the period 2008-2016 was developed, based on crop yield data. Emissions of species of volatile organic compounds(VOCs)and corresponding ozone formation potential (OFP) in 2016 were also estimated. Results showed that emissions of atmospheric pollutants from crop residue burning in 2013-2016 were lower than in 2008-2012. This was mainly due to the policy of prohibiting open burning of straw and to improvement of rural living standards, which reduced the proportion of straw burning. In 2016, emissions of SO2, NOx, NH3, CH4, EC, OC, NMVOC, CO, and PM2.5 were 2443.7, 16187.9, 6943.8, 29174.4, 3625.5, 14830.7, 65612.6, 591613.9, and 49463.0 t, respectively. Rice straw burning was the main source of pollutants, accounting for about 68.55% of total pollutant emissions. The five municipalities with highest atmospheric pollutant emissions were Zhanjiang, Maoming, Meizhou, Zhaoqing, and Shaoguan, together accounting for about 58.63% of total emissions. The top 10 VOC species for mass-based emissions consisted of ethylene, acetaldehyde, formaldehyde, benzene, ethyne, propylene, ethane, toluene, propane, and propionaldehyde, together contributing 67.91% to total emissions. The top ten OFP-based VOC species were ethylene, formaldehyde, acetaldehyde, propylene, 1-butylene, propionaldehyde, toluene, acrolein, isoprene, and crotonaldehyde, accounting for 80.83% of total OFP.

3.
Huan Jing Ke Xue ; 39(1): 49-56, 2018 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965665

RESUMO

To meet the requirements of regional air quality management (AQM), the Air Quality Subarea Management (AQSM) system was proposed. A case study was conducted for Guangdong Province. By using the method of air quality numerical simulation and satellite remote sensing inversion analysis, the key factors were selected from the meteorological simulation field, the pollutant concentration simulation field, and the satellite image interpretation to form the index system for AQSM. On this basis, a hierarchical cluster analysis method was used to divide Guangdong Province into three types of AQSM:Strict Control Subarea, Continuous Improvement Subarea, and Coordinated Development Subarea. It was shown that the Strict Control Subarea, Continuous Improvement Subarea, and Coordinated Development Subarea in Guangdong Province covered 16.3%, 28.0%, and 55.7%, respectively. The Strict Control Subarea in the Pearl River Delta, Eastern Guangdong, Western Guangdong, and Northern Guangdong accounted for 27.9%, 19.3%, 4.4%, and 12.5%, respectively, and the subarea should implement the most stringent AQM policies to promote air quality improvement. The Continuous Improvement Subarea in the Pearl River Delta, Eastern Guangdong, Western Guangdong, and Northern Guangdong accounted for 34.4%, 15.8%, 7.8%, and 34.5%, respectively, and the subarea should implement relatively strict AQM policies to ensure sustained and stable standards. The Coordinated Development Subarea in the Pearl River Delta, Eastern Guangdong, Western Guangdong, and Northern Guangdong accounted for 37.7%, 64.9%, 87.8%, and 53.0%, respectively, and the subarea could implement more liberal AQM policies to ensure relatively good air quality. In general, the strict AQM policies in Guangdong Province should be mainly concentrated in the Pearl River Delta region, followed by Northern Guangdong, Eastern Guangdong, and Western Guangdong in order.

4.
Huan Jing Ke Xue ; 39(8): 3485-3491, 2018 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29998652

RESUMO

Atmospheric environmental capacity is an important reference in environmental planning. To meet the PM2.5 standard, a new method is proposed to balance the capacity among cities of Guangdong, with screening of the most unfavorable meteorological year and combining it with the regional transportation calculated by the CAMx-PSAT module. Pollutant overloading and capacity scenarios were also calculated. The results showed that, under the constraints of the cities' annual PM2.5 ≤ 35 µg·m-3, the capacities of SO2, NOx, NH3, and PM2.5 in Guangdong were about 6.8×105 tons, 1.35×106 tons, 4.6×105 tons, and 5.1×105 tons, respectively. Based on the benchmark scenario, SO2 emissions in Guangdong were overloaded by 10%, and the emissions of NOx, NH3, and PM2.5 exceeded by 12%, 9%, and 20%, respectively, compared to those of the capacity scenario. Ranked by the number of overloaded species in Guangdong, the cities of Guangzhou, Foshan, Zhongshan, and Qingyuan were on top. When achieving the capacity scenario, the annual PM2.5 concentration in Guangdong was about 30 µg·m-3, which meets the national secondary ambient air quality standard.

5.
Nat Commun ; 8: 14220, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28140389

RESUMO

Fossilized organic remains are important sources of information because they provide a unique form of biological and evolutionary information, and have the long-term potential for genomic explorations. Here we report evidence of protein preservation in a terrestrial vertebrate found inside the vascular canals of a rib of a 195-million-year-old sauropodomorph dinosaur, where blood vessels and nerves would normally have been present in the living organism. The in situ synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectra exhibit the characteristic infrared absorption bands for amide A and B, amide I, II and III of collagen. Aggregated haematite particles (α-Fe2O3) about 6∼8 µm in diameter are also identified inside the vascular canals using confocal Raman microscopy, where the organic remains were preserved. We propose that these particles likely had a crucial role in the preservation of the proteins, and may be remnants partially contributed from haemoglobin and other iron-rich proteins from the original blood.


Assuntos
Colágeno/análise , Fósseis/diagnóstico por imagem , Costelas/química , Amidas/análise , Amidas/história , Animais , Colágeno/história , Dinossauros/anatomia & histologia , Dinossauros/fisiologia , Compostos Férricos/análise , Compostos Férricos/história , Fósseis/anatomia & histologia , Fósseis/história , História Antiga , Costelas/anatomia & histologia , Costelas/irrigação sanguínea , Costelas/diagnóstico por imagem , Espectroscopia de Infravermelho com Transformada de Fourier , Síncrotrons
6.
J Biomed Mater Res A ; 102(7): 2248-57, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23913750

RESUMO

In our previous study, we found that cartilage fragments from osteoarthritic knee promoted chondrogenesis of mesenchymal stem cells. In this study, we further transformed the cartilage tissues into acellular cartilage matrix (ACM) and explored the feasibility of using ACM as a biological scaffold. Nonworn parts of cartilage tissues were obtained during total knee arthroplasty (TKA) surgery and were successfully fabricated into ACM powders. The ACM powders and human synovium-derived mesenchymal stem cells (SMSCs) were mixed into collagen gel for in vitro culture. Histological results showed a synergistic effect of ACM powders and chondrogenic growth factors in the formation of engineered cartilage. The findings of real-time polymerase chain reaction (PCR) suggested that ACM powders had the potential of promoting type II collagen gene expression in the growth factors-absent environment. Moreover, with growth factors induction, the ACM powders could reduce the hypertrophy in chondrogenesis of SMSCs. In summary, ACM powders could serve as a functional scaffold that benefited the chondrogenesis of SMSCs for cartilage tissue engineering.


Assuntos
Cartilagem/crescimento & desenvolvimento , Células-Tronco Mesenquimais/citologia , Membrana Sinovial/citologia , Engenharia Tecidual , Tecidos Suporte , Idoso , Humanos , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
7.
J Orthop Res ; 30(3): 393-400, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22267189

RESUMO

Extracellular matrix (ECM) is thought to participate significantly in guiding the differentiation process of mesenchymal stem cells (MSCs). In this study, we hypothesized that cartilage fragments from osteoarthritic knee could promote chondrogenesis of MSCs. Nonworn parts of cartilage tissues were obtained during total knee arthroplasty (TKA) surgery. Cartilage fragments and MSCs were wrapped into fibrin glue; and the constructs were implanted subcutaneously into nude mice. Histological analysis showed neocartilage-like structure with positive Alcian blue staining in the cartilage fragment-fibrin-MSC constructs. However, constructs with only MSCs in fibrin showed condensed appearance like MSCs in the pellet culture. Gene expression of type II collagen in the constructs with 60 mg cartilage fragments were significantly elevated after 4 weeks of implantation. Conversely, the constructs without cartilage fragments failed to express type II collagen, which indicated MSCs did not differentiate into a chondrogenic lineage. In conclusion, we demonstrated the effect of cartilage fragments from osteoarthritic knee in promoting chondrogenic differentiation of MSCs. This may be a favorable strategy for MSC chondrogenesis without exogenous growth factor induction.


Assuntos
Cartilagem/fisiologia , Condrogênese , Regeneração Tecidual Guiada , Células-Tronco Mesenquimais/fisiologia , Animais , Artroplastia do Joelho , Cartilagem/citologia , Diferenciação Celular , Colágeno Tipo II/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Osteoartrite do Joelho/cirurgia
8.
Clin Immunol ; 119(1): 21-31, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16406844

RESUMO

There is an increasing realization that the failure of adoptive therapy with cytotoxic T lymphocytes in the autologous setting, at least in part, results from the lack of help from antigen-specific CD4+ T cells. To incorporate these cells into this treatment strategy, it is not known whether currently used ex vivo culture conditions are adequate for expanding and charting these T cells with the desired qualities for optimal in vivo activity. In this study, we show that stimulation with agonistic antibodies to CD3 plus CD28 (anti-CD3/CD28), a commonly used method for CD4+ T cell expansion, is unable to expand dendritic-cell-activated hepatitis B virus (HBV)-specific CD4+ T cells to clinical relevant numbers. Whereas, in combination with interleukin(IL)-7 and IL-15, it leads to a 4000-fold expansion of HBV-specific CD4+ T cells in 2 weeks. This outcome is correlated with the anti-apoptosis effect of IL-7 and IL-15. Importantly, antigen specificity is preserved during expansion. Although a late addition of IL-2 to the anti-CD3/CD28-expanding cultures also results in robust expansion, this expansion condition renders HBV-specific CD4+ T cells more sensitive to cytokine withdrawal-, activation-, and transforming growth factor-beta-induced cell death compared to those expanded in IL-7 and IL-15. Moreover, NKG2D rather than 4-1BB, whose ligands are constitutively expressed on tumor cells, is significantly up-regulated on IL-7/IL-15-expanded HBV-specific CD4+ T cells, and its engagement promotes expansion and interferon-gamma production by these cells and thus may serve to provide co-stimulation to T cells once they reach tumor tissues. Collectively, these results may have important therapeutic implications for adoptive T cell therapy.


Assuntos
Anticorpos/farmacologia , Antígenos CD/imunologia , Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Interleucinas/farmacologia , Ativação Linfocitária/imunologia , Antígenos CD/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Antígenos CD28/imunologia , Complexo CD3/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Técnicas de Cultura de Células/métodos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/imunologia , Humanos , Imunoterapia Adotiva/métodos , Interferon gama/metabolismo , Interleucina-15/farmacologia , Interleucina-2/farmacologia , Interleucina-7/farmacologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Receptores Imunológicos/imunologia , Receptores Imunológicos/metabolismo , Receptores de Interleucina-2/metabolismo , Receptores de Células Matadoras Naturais , Receptores de Fator de Crescimento Neural/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Transfecção , Fator de Crescimento Transformador beta/farmacologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral
9.
Immunol Lett ; 86(1): 37-43, 2003 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-12600743

RESUMO

Transforming growth factor-beta (TGF-beta), found at the site of most tumors, has been recognized as one of the mechanisms involved in tumor immunological escape. To evaluate its impact on adoptive immunotherapy against cancer, we examined the susceptibility of tumor-specific T cells to TGF-beta in the setting of these T cells being prepared for adoptive transfer. Hepatitis B virus (HBV)-specific CD4(+) T cells were ex vivo generated by activating with HBV-transfected dendritic cells and selecting with antibodies to CD25 activation molecules, and then expanded with antibodies to CD3/CD28. These T cells expressed higher levels of the type II TGF-beta receptor than nai;ve T cells and exhibited enhanced apoptosis when exposed to TGF-beta. The underlying apoptotic pathway was linked to the dissipation of the mitochondrial inner membrane potential and activation of caspase-9. The absence of caspase-8 activity in TGF-beta-treated T cells suggests that the death receptor system may not be involved in this type of apoptosis. Interleukin-2 (IL-2), which is concomitantly administered with tumor-specific T cells in adoptive immunotherapy, was unable to protect HBV-specific CD4(+) T cells from the pro-apoptotic effect of TGF-beta when added simultaneously with TGF-beta. Interesting, IL-2-pretreated T cells displayed the type II TGF-beta receptor at lower levels and were more resistant to TGF-beta. Together, our findings indicate that the effectiveness of adoptive cancer immunotherapy may be impaired by tumor-derived TGF-beta and appropriate manipulation of exogenous IL-2 might overcome this hurdle.


Assuntos
Apoptose/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Imunoterapia Adotiva , Fator de Crescimento Transformador alfa/metabolismo , Animais , Linfócitos T CD4-Positivos/patologia , Caspase 9 , Caspases/imunologia , Meios de Cultivo Condicionados/química , Fragmentação do DNA/imunologia , Células Dendríticas/imunologia , Citometria de Fluxo , Antígenos de Superfície da Hepatite B/imunologia , Humanos , Separação Imunomagnética , Marcação In Situ das Extremidades Cortadas , Interferon gama/metabolismo , Interleucina-2/imunologia , Interleucina-2/metabolismo , Ativação Linfocitária/fisiologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Proteínas Serina-Treonina Quinases , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/biossíntese
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