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1.
Huan Jing Ke Xue ; 45(8): 4432-4439, 2024 Aug 08.
Artículo en Chino | MEDLINE | ID: mdl-39168663

RESUMEN

Satellite-based formaldehyde(HCHO)columns and tropospheric nitrogen dioxide columns were observed using the Ozone Monitoring Instrument(OMI),and groundbased observations of ozone(O3)for May-August from 2013 to 2022 were connected to calculate the threshold values of the HCHO to NO2 ratio(FNR)in Shanxi Province. Then,the spatiotemporal distributions and variations in summertime ozone photochemical production regimes were analyzed. The results showed that:① The volatile organic compound(VOC) -sensitive regime area(FNR < 2.3)was obviously reduced,while the VOCs-NOx transitional regime(FNR between 2.3-4.1)area increased in the early years and then decreased, and NO x -sensitive regime area expanded significantly in summer from 2013 to 2022 over Shanxi Province. ② The increased summertime FNR during 2013 to 2019 was associated with the co-effect of increased HCHO columns and decreased tropospheric NO2 columns. The Shanxi Province was generally under an NOx regime since 2016,which reflected the remarkable effect of NO x emission reductions;however,there was a shift from a VOC-sensitive regime to a VOCs-NOx transitional regime,in which O3 pollution aggravation was widespread under the background of decreased NOx emissions. The decrease in O3 concentration during 2020 to 2022 followed the synergistical declines in HCHO columns and tropospheric NO2 columns. ③ The O3 weekend effects were reversed in Linfen and Yuncheng but were persistent in the other nine cities. Satellite-based weekend HCHO and NO2 levels were higher than those on weekdays in some cities of Shanxi Province,indicating that the O3 weekend effect was not only dependent on the changes of precursors emissions but was also closely related to O3 photochemical production sensitivity. The results indicated the necessity of simultaneous controls in NOx emissions and VOCs emissions for ozone abatement plans over Shanxi Province. In addition,Taiyuan,Yangquan,Yuncheng,and Jincheng should continue to promote reduction in NOx emissions.

2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 20(6): 1327-31, 2012 Dec.
Artículo en Chino | MEDLINE | ID: mdl-23257426

RESUMEN

This study was aimed to investigate the proliferation inhibition and apoptosis induction of cucurmosin (CUS) combined with all trans-retinoic acid (ATRA) or arsenic trioxide (ATO) on human acute promyelocytic leukemia cell line NB4. MTT method was used to determine the proliferative inhibition of CUS combined with ATRA or ATO on NB4 cells, and flow cytometry was used to determine the apoptosis induction effect of CUS combined with ATRA or ATO on NB4 cells. Jin's formula was used to assess the synergistic effect of this combinations. The results showed that, compared with single drug, the proliferation inhibitory ratio and apoptotic ratio of CUS combined with ATRA or ATO on NB4 cells was higher than CUS, ATRA and ATO alone. The synergistic index (q) were all larger than 0.85, and the combined effects were significant at low concentrations. It is concluded that the CUS combined with ATRA or ATO synergistically increases the effects of proliferative inhibition and apoptosis induction on NB4 cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Leucemia Promielocítica Aguda/patología , Proteínas de Plantas/farmacología , Trióxido de Arsénico , Arsenicales/farmacología , Línea Celular Tumoral , Sinergismo Farmacológico , Humanos , Óxidos/farmacología , Tretinoina/farmacología
3.
Zhonghua Yan Ke Za Zhi ; 45(3): 243-7, 2009 Mar.
Artículo en Chino | MEDLINE | ID: mdl-19575920

RESUMEN

OBJECTIVE: To analyze the characteristics of the retrobulbar blood vessels' hemodynamics changes and the choroidal circulation disorder, and to observe the relations between retinal pigment epithelium's (RPE) pathological changes and them. METHODS: It was a case control study. For 57 (57 affected eyes and 57 contralateral eyes) unilateral eye affected patients and 25 (50 eyes) normal health adults, we examined ophthalmic arteries (OA), posterior ciliary arteries (PCA) and short posterior ciliary arteries (SPCA) by color Doppler flow Imaging (CDFI), and recorded the peak systolic velocities (PSV), end diastolic velocities (EDV) and resistance indexes (RI) of them. We compared each hemodynamic parameter of the normal eyes with it of the affected eyes and contralateral eyes in patients group respectively, and contrasted them between affected eyes and contralateral eyes of the patients. Fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were performed simultaneously on 57 patients with Heidelberg retina angiography, and the images were analyzed in contrast. We used SPSS 12.0 statistics software was used in the study. To the PSV, EDV and RI of the OA, PCA and SPCA in affected eyes and contralateral eyes of the patients, we used paired t-test for the same sample to compare their hemodynamic parameters; to compare normal health adults' eyes with the affected eyes and the contralateral eyes of patients group respectively, we used two-group t-test. When the P-value was less than 0.05, there was a statistical significance. RESULTS: There was a more significant decrease of the hemodynamic parameters in both PSVs and EDVs of temporal PCAs (PSV: t = 3.044, P = 0.005; EDV: t = 3.731, P = 0.001) and temporal SPCAs (PSV: t = 2.822, P = 0.008; EDV: t = 3.194, P = 0.003) compared the patients group's affected eyes with normal health adults group eyes, there was a more significant decrease of them of temporal PCAs (PSV: t = 3.219, P = 0.003; EDV: t = 3.807, P = 0.001) and temporal SPCAs (PSV: t = 3.931, P = 0.000, EDV: t = 3.145, P = 0.003) compared the patients group's contralateral eyes with normal health adults group eyes, and there was a statistical significance of them (P < 0.05). There was no difference in hemodynamic parameters of both PSVs and EDVs of temporal PCAs (PSV: t = 0.608, P = 0.548; EDV: t = 0.122, P = 0.904) and temporal SPCAs (PSV: t = 0.730, P = 0.470; EDV: t = 0.109, P = 0.914) between affected eyes and contralateral eyes of the patients, and there was no statistical significance of them (P > 0.05). The results of FFA and ICGA showed that all the RPE's leaks of 57 affected eyes appeared at the hypofluorescent regions of relative choroids; 52 cases of 57 affected eyes were followed by choroidal vessels dilatation at the early hypofluorescent regions, and appeared hyperfluorescence leakages in the late phase images; At the all regions of RPE's transmitted fluorescences of affected eyes and contralateral eyes, the corresponding choroids showed hyperfluorescence in the late phase images in ICGA; There were no RPE's transmitted fluorescences at the regions of 20 affected eyes and 16 contralateral eyes in FFA, which showed hyperfluoresceince leakages in the late phase images of choroids in ICGA. CONCLUSIONS: CSC is possibly a bilateral disease associated with systemic pathologic conditions. Hypoperfusion and ischemia are the basal characteristics of retrobulbar blood vessels' circulation disorder and choroidal ultracirculation disorder. The damage of RPE is following to the choroidal circulation disorder.


Asunto(s)
Coriorretinopatía Serosa Central/diagnóstico por imagen , Coriorretinopatía Serosa Central/fisiopatología , Ojo/irrigación sanguínea , Ojo/diagnóstico por imagen , Adulto , Estudios de Casos y Controles , Ojo/fisiopatología , Femenino , Angiografía con Fluoresceína , Fondo de Ojo , Hemodinámica , Humanos , Verde de Indocianina , Masculino , Persona de Mediana Edad , Arteria Oftálmica , Radiografía
4.
Zhonghua Yan Ke Za Zhi ; 40(4): 266-71, 2004 Apr.
Artículo en Chino | MEDLINE | ID: mdl-15268837

RESUMEN

OBJECTIVE: Endostatin is an endogeneous angiogenesis inhibitor. The purpose of this study was to investigated the effect of Endostatin on the eyes of rats with experimental choroidal neovascularization (CNV). METHODS: Experimental CNV was induced by laser photocoagulation. Animals were given subretinal injections of recombinant human Endostatin 20 microl (5 g/L) or 0.9% chlorine sodium. The intensity of fluorescein leakage from the photocoagulated lesions was studied 13 days after photocoagulation. The area of CNV at each rupture site was measured using high molecular weight FITC-dextran (MW 2 x 10(6)) for high resolution angiography in RPE-choroid-sclera flat mounts. In addition, 8 eyes in each group were removed and fixed 14 days after photocoagulation, cut into thin sections. The sections were examined by light microscopy. Immunolocalization of Endoglin (CD105) and factor VIII on sections of CNV lesions was studied by immunohistochemical evaluation. RESULTS: After Endostatin injection, fluorescein leakage from the CNV lesions decreased significantly compared with the control eyes. The average area of CNV at sites of the Bruch's membrane rupture showed significant difference in eyes injected with Endostatin compared with control eyes. Endothelial cells demonstrated strong immunoreactivity of CD105 and factor VIII in CNV lesions of control eyes. CD105-positive cell were not detected in normal chorioretinal tissues. CONCLUSIONS: The development of CNV can be inhibited by injection of Endostatin, which suggest that Endostatin may be beneficial in treating CNV and that further studies can be considered to evaluate this possibility.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Neovascularización Coroidal/prevención & control , Endostatinas/farmacología , Inhibidores de la Angiogénesis/administración & dosificación , Animales , Antígenos CD , Western Blotting , Neovascularización Coroidal/etiología , Neovascularización Coroidal/metabolismo , Electroforesis en Gel de Poliacrilamida , Endoglina , Endostatinas/administración & dosificación , Ojo/irrigación sanguínea , Ojo/química , Ojo/efectos de los fármacos , Inmunohistoquímica , Coagulación con Láser/efectos adversos , Masculino , Ratas , Receptores de Superficie Celular , Retina/química , Retina/efectos de los fármacos , Retina/patología , Molécula 1 de Adhesión Celular Vascular/análisis
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