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1.
J Org Chem ; 89(1): 44-56, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38088910

RESUMEN

In this paper, we present an example of a photoinduced catalyst, halogen-, and base-free TEMPO-mediated interrupted 6π-photocyclization/dehydrogenative aromatization of ortho-biaryl-appended 1,3-dicarbonyl compounds for the preparation of 10-phenanthrenols. The reaction involves rapid photocycloaddition via a 1,2-biradical of 1,3-dicarbonyl compounds, followed by subsequent dehydrogenative aromatization of 1,4-biradical intermediates using TEMPO as the commercially available oxidant rather than trapped by TEMPO to form an alkoxyamine product.

2.
J Org Chem ; 88(21): 14874-14886, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37862710

RESUMEN

An efficient oxidant-free, photoredox-mediated cascade cyclization strategy for the synthesis of 1,3,4-oxadiazoles by using an organo acridinium photocatalyst and a cobaloxime catalyst has been developed. Various acylhydrazones have been transformed into the corresponding 1,3,4-oxadiazole products in up to 96% yield, and H2 is the only byproduct. Mechanistic experiments and density functional theory (DFT) calculation studies indicate carbon-centered radicals rather than oxygen-centered radicals as π-radicals produced by the oxidation of photoexcited Mes-Acr+* along with deprotonation, which is responsible for this transformation. The practical utility of this method is highlighted by the one-pot gram-scale synthesis starting directly from commercially available aldehydes and acylhydrazides.

3.
J Org Chem ; 88(13): 9094-9104, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37314129

RESUMEN

A photocatalyst- and additive-free visible-light-induced 6π-photocyclization of ortho-biaryl-appended ß-ketoesters has been developed. Upon irradiation with visible light, substrates undergo 6-endo-trig cyclization/1,5-H shift to 9,10-dihydrophenanthren-9-ols with high efficiency and selectivity. The reaction proceeds via conrotatory ring closure followed by a suprafacial 1,5-hydrogen shift leading to the observed single trans-fused products. Preliminary mechanistic studies reveal the feasibility of both 1,5-H shift and intersystem crossing of the diradical intermediate.


Asunto(s)
Hidrógeno , Luz , Ciclización
4.
J Org Chem ; 87(24): 16458-16472, 2022 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-36441578

RESUMEN

Due to the inert redox activity and high triplet energy, radical chemistry of 1,3-dicarbonyl compounds usually requires prefunctionalization substrates, external oxidant, and high-energy UV light. Here, we report a visible-light-driven photocatalyst/cobaloxime system composed of a photosensitized energy transfer reaction (PEnT) and photoinduced electron transfer reaction (PET) and with an interrupted 6π-photocyclization/dehydrogenative aromatization in one pot to synthesize 10-phenanthrenols. Preliminary mechanistic studies revealed that fac-Ir(ppy)3 plays the dual roles of energy transfer catalysis for photocycloaddition via 1,2-biradical intermediates of 1,3-dicarbonyl compounds and photoredox/cobaloxime catalysis dehydrogenative aromatization of 1,4-biradical rather than the intermediates via 6π photocyclization in the tandem reaction. In contrast to previous well-established radical chemistry of 1,3-dicarbonyl compounds, we provide a new strategy for the activation of 1,3-dicarbonyl compounds under visible light catalysis, affording a novel cyclization strategy with extremely high atom economy for the synthesis of 10-phenanthrenols.


Asunto(s)
Cobalto , Electrones , Oxidación-Reducción , Catálisis , Transferencia de Energía
5.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(4): 643-653, 2022 Aug.
Artículo en Zh | MEDLINE | ID: mdl-36065698

RESUMEN

Objective To clarify the hotspots and trends of multimorbidity research and to provide evidence for further research in China. Methods Papers on multimorbidity were retrieved from PubMed and Web of Science (from inception to August 11,2021).BICOMB and gCLUTO were used for bibliometric and clustering analysis,and CiteSpace was employed for analysis of authors and citations,and burst detection of keywords. Results The research on multimorbidity has been on the rise.Among the authors,Mercer SW published the most papers on this topic and Fortin M was the most cited author.Karolinska Institute topped the institutions in the number of published papers,and the paper published in Lancet by Barnett K in 2012 was the most cited.A total of 75 high-frequency keywords were extracted,on the basis of which seven research hotspots were summarized:epidemiology (including the prevalence and trend),medication (involving polypharmacy,medication compliance,etc.),medical expenditure (including cost and medical services),aging (such as elderly patients,frailty,and disability),psychology (involving mental health,social support,etc.),multimorbidity management (such as the treatment,primary health care,and integrated care),and comorbidity of cardiovascular and metabolic diseases (involving obesity,stroke,diabetes,etc.). Conclusions Multimorbidity is concerned as a major health threat and public health problem worldwide.The management of multimorbidity is more complex than that of one disease,which thus faces more challenges.Therefore,researchers,health care providers,and policy-makers should underscore it.


Asunto(s)
Bibliometría , Multimorbilidad , Anciano , China/epidemiología , Comorbilidad , Humanos
6.
Health Qual Life Outcomes ; 19(1): 103, 2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33752686

RESUMEN

BACKGROUND: More than 210,000 medical workers have fought against the outbreak of Coronavirus Disease 2019 (COVID-19) in Hubei in China since December 2019. However, the prevalence of mental health problems in frontline medical staff after fighting COVID-19 is still unknown. METHODS: Medical workers in Wuhan and other cities in Hubei Province were invited to participate a cross-sectional and convenience sampling online survey, which assessed the prevalence of anxiety, insomnia, depression, and post-traumatic stress disorder (PTSD). RESULTS: A total of 1,091 responses (33% male and 67% female) were valid for statistical analysis. The prevalence was anxiety 53%, insomnia 79%, depression 56%, and PTSD 11%. Healthcare workers in Wuhan were more likely to face risks of anxiety (56% vs. 52%, P = 0.03) and PTSD (15% vs. 9%, P = 0.03) than those in other cities of Hubei. In terms of educational attainment, those with doctoral and masters' (D/M) degrees may experience more anxiety (median of 7.0, [interquartile range (IQR) 2.0-8.5] vs. median 5.0 [IQR 5.0-8.0], P = 0.02) and PTSD (median 26.0 [IQR 19.5-33.0] vs. median 23.0 [IQR 19.0-31.0], P = 0.04) than those with lower educational degrees. CONCLUSIONS: The mental problems were an important issue for the healthcare workers after COVID-19. Thus, an early intervention on such mental problems is necessary for healthcare workers.


Asunto(s)
COVID-19 , Trastorno Depresivo/epidemiología , Brotes de Enfermedades , Personal de Salud/psicología , Enfermedades Profesionales/epidemiología , SARS-CoV-2 , Adulto , China/epidemiología , Estudios Transversales , Trastorno Depresivo/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/psicología , Prevalencia , Psicometría , Calidad de Vida , Encuestas y Cuestionarios , Adulto Joven
7.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 43(3): 357-365, 2021 Jun 30.
Artículo en Zh | MEDLINE | ID: mdl-34238411

RESUMEN

Objective To establish a mouse model of exogenous iron overload combined with tuberculosis(TB). Methods C57BL/6N mice were divided into negative control, low-, medium-, and high-dose iron groups and received intraperitoneal injection of iron dextran at 0, 3.75, 7.50, and 15.00 mg/dose(3 times/week for 4 weeks), respectively.After 4 weeks, the organ morphology and body weight of the mice were evaluated.The content of serum iron, ferritin, transferrin, and transferrin receptor was determined by ELISA.Heart, liver, spleen, lung, kidney, and small intestine were analyzed for tissue iron content and iron deposition pathology.Mycobacterium tuberculosis(Mtb)standard strain H37Rv was injected via tail vein to infect the mice receiving moderate-dose iron to establish an iron-overloaded mouse model of active TB.HE staining and Mtb culture were employed to analyze tuberculous lesions and bacterial loads of lung, spleen and liver tissues. Results The weight gain percentages of mice in the negative control, low-, medium-, and high-dose iron groups were 25.47%, 25.22%, 24.74%, and 21.36%, respectively, which was significantly lower in the high-dose group than in the negative control(F=17.235, P=0.027), low-dose(F=15.206, P=0.031), and medium-dose(F=11.061, P=0.036)groups.Liver had the highest iron content, followed by spleen, kidney, and small intestine.The iron content in heart and lung tissues of the low-dose group had no significant difference compared with those of the negative control group(F=19.023, P=0.715;F=23.193, P=0.902).Serum iron and ferritin in the iron-overloaded mice increased in a dose-dependent manner, while transferrin and transferrin receptor had no significant changes.HE and Prussian blue staining showed that the iron-overloaded mice had different degrees of iron deposition in tissues and high-dose iron caused liver and kidney damage.The lung(F=23.227, P=0.017), spleen(F=19.023, P=0.021), and liver(F=17.392, P=0.009)of the iron-overloaded mice with TB had a significantly shorter time of bacterial culture than those of the TB-infected mice without iron overload.The lung(F=21.012, P=0.007), spleen(F=20.173, P=0.002), and liver(F=19.091, P=0.005)of the iron-overloaded mice with TB had significantly higher bacterial loads than those of the TB-infected mice without iron overload. Conclusions The exogenous iron-overloaded mouse model with similar symptoms to patients with clinical iron overload can be established by intraperitoneal injection of medium-dose(7.50 mg/dose, 3 times/week for 4 weeks)iron dextran.Mtb injection through the tail vein can help construct a mouse model of iron overload combined with active TB.


Asunto(s)
Sobrecarga de Hierro , Tuberculosis , Animales , Humanos , Hierro , Complejo Hierro-Dextran , Ratones , Ratones Endogámicos C57BL
8.
J Cell Mol Med ; 23(11): 7673-7684, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31468674

RESUMEN

Stromal cell-derived factor-1 (SDF-1) is a well-characterized cytokine that protects heart from ischaemic injury. However, the beneficial effects of native SDF-1, in terms of promoting myocardial repair, are limited by its low concentration in the ischaemic myocardium. Annexin V (AnxA5) can precisely detect dead cells in vivo. As massive cardiomyocytes die after MI, we hypothesize that AnxA5 can be used as an anchor to carry SDF-1 to the ischaemic myocardium. In this study, we constructed a fusion protein consisting of SDF-1 and AnxA5 domains. The receptor competition assay revealed that SDF-1-AnxA5 had high binding affinity to SDF-1 receptor CXCR4. The treatment of SDF-1-AnxA5 could significantly promote phosphorylation of AKT and ERK and induce chemotactic response, angiogenesis and cell survival in vitro. The binding membrane assay and immunofluorescence revealed that AnxA5 domain had the ability to specifically recognize and bind to cells injured by hypoxia. Furthermore, SDF-1-AnxA5 administered via peripheral vein could accumulate at the infarcted myocardium in vivo. The treatment with SDF-1-AnxA5 attenuated cell apoptosis, enhanced angiogenesis, reduced infarcted size and improved cardiac function after mouse myocardial infarction. Our results suggest that the bifunctional SDF-1-AnxA5 can specifically bind to dead cells. The systemic administration of bifunctional SDF-1-AnxA5 effectively provides cardioprotection after myocardial infarction.


Asunto(s)
Anexina A5/metabolismo , Quimiocina CXCL12/metabolismo , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/fisiopatología , Proteínas Recombinantes de Fusión/uso terapéutico , Administración Intravenosa , Animales , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Quimiotaxis/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Masculino , Ratones Endogámicos C57BL , Infarto del Miocardio/patología , Isquemia Miocárdica/fisiopatología , Miocardio/metabolismo , Miocardio/patología , Neovascularización Fisiológica/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Receptores de Quimiocina/metabolismo , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/farmacología , Transducción de Señal/efectos de los fármacos
9.
Am J Forensic Med Pathol ; 38(3): 199-210, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28590265

RESUMEN

The expression of keratinocyte growth factor-1 (KGF-1) and keratinocyte growth factor-2 (KGF-2) in skin wounds in mice was studied using multiple methods. The dynamic expression of KGF-1 and KGF-2 for antemortem and postmortem injuries as well as the examination of antemortem injuries after death under different temperature and over varying time periods was studied. It demonstrates that skin KGF-1 resulting from an antemortem injury starts to rise at 6 hours, reaches its peak at 1 day, and starts to drop at 5 days. The expression of skin KGF-2 resulting from an antemortem injury starts to rise at 12 hours, reaches its peak at 7 days, and begins to drop at 10 days. Skin KGF-1 and skin KGF-2 after death stabilize within 7 days at 4°C and -20°C, within 5 days at 20°C, and within 1 day at 30°C. The application of KGF-1 and KGF-2 indicators in skin wound age determination is both feasible and reliable.


Asunto(s)
Factor 10 de Crecimiento de Fibroblastos/metabolismo , Factor 7 de Crecimiento de Fibroblastos/metabolismo , Piel/lesiones , Piel/metabolismo , Animales , Western Blotting , Factor 10 de Crecimiento de Fibroblastos/genética , Factor 7 de Crecimiento de Fibroblastos/genética , Patologia Forense/métodos , Inmunohistoquímica , Ratones Endogámicos ICR , Microscopía , Cambios Post Mortem , ARN Mensajero/metabolismo , Piel/patología , Factores de Tiempo
10.
Cytotherapy ; 17(12): 1746-62, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26455275

RESUMEN

BACKGROUND AIMS: The aim of this study was to investigate whether active specific immunotherapy (ASI) is able to demonstrate therapeutic efficacy against colorectal cancer. METHODS: We conducted a systematic review of published papers from MEDLINE, the Cochrane Central Register of Controlled Trials, EMBASE, the Wanfang Database, the China Science and Technology Periodical Database and China Journal Net. Published data were extracted independently by two authors who used predefined database templates. The effects of ASI were compared with those of surgery alone, and a pooled analysis was performed with the use of the data from random- or fixed-effect models. RESULTS: Twelve trials matched our inclusion criteria (n = 2993, including 1842 control subjects). The overall analysis showed a significant survival benefit [1-, 2-, 3-, 4-, 5-, 6- and 7-year overall survival (OS), P < 0.05; 10-year OS, P < 0.001] in favor of ASI immunotherapy combined with surgery, but there was not an improvement in the 8- or 9-year OS (P > 0.05). The disease-free survival (DFS) rate was improved after the combination of ASI immunotherapy (2-, 3-, 5- and 10-year DFS, P < 0.05), but no significant improvement was noted for the 1-, 4-, 6-, 7-, 8- or 9-year DFS (P > 0.05). In addition, the disease-specific survival (DSS) was improved at some time points after the combination of ASI immunotherapy and surgery (2-, 3-, 4-, 5- and 6-year DSS, P < 0.05, but not the 1-, 7-, 8- or 9-year DSS, P > 0.05). An improved 2-, 3-, 4-, 5- and 6-year recurrence-free interval (RFI) (P < 0.05) was also observed in patients who received ASI therapy, but this was not observed for the 1-year RFI (P > 0.05). Furthermore, an analysis of the recurrence-free survival (RFS) showed that it was significantly increased in the ASI plus surgery group (1-, 2-, 3-, 4-, 5- and 6-year RFS, P < 0.001). The funnel plots showed that the analyses were relatively reliable and the publication bias was small. CONCLUSIONS: The combination of ASI immunotherapy and surgery was superior in prolonging the overall survival time and enhancing the recurrence-free survival rate compared with surgery alone.


Asunto(s)
Neoplasias Colorrectales/terapia , Inmunoterapia/métodos , Neoplasias Colorrectales/mortalidad , Supervivencia sin Enfermedad , Humanos , Recurrencia Local de Neoplasia/terapia , Tasa de Supervivencia
11.
Cytotherapy ; 17(7): 956-68, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25824289

RESUMEN

BACKGROUND AIMS: In this study, we investigate whether bone marrow mononuclear cells (BM-MNC) or peripheral blood mononuclear cells (PB-MNC) have therapeutic efficacy in type 2 diabetes (T2D). METHODS: Search terms included stem cell, bone marrow cell, peripheral blood cell, umbilical cord blood and T2D in MEDLINE, the Cochrane Controlled Trials Register, EMBASE, the Wanfang Database, the China Science and Technology Periodical Database and China Journal Net. RESULTS: Fifteen trials met our inclusion criteria (n = 497). One group included 266 cases with BM-MNC therapy and the other group contained 231 cases with PB-MNC treatment. Glycosylated hemoglobin was decreased after BM-MNC or PB-MNC therapy compared with that before (12 months: P < 0.001; 6 months: P < 0.001; 3 months: P < 0.05). Fasting plasma glucose was reduced in BM-MNC therapy group compared with control after 12-month follow-up (P < 0.001) and after BM-MNC therapy compared with that before (9 months: P < 0.001) but was not obvious in other stages. Meanwhile, the analysis showed that C-peptide level increased after BM-MNC and PB-MNC therapy compared with the control therapy (12 months: P < 0.001) and with that before therapy (6 months: P < 0.05). Insulin requirement reduction was also observed in patients receiving BM-MNC therapy (3, 6, 9 and 12 months: P < 0.05). CONCLUSIONS: To a certain extent, BM-MNC or PB-MNC therapy for T2D demonstrated superiority of glycemic control, increased insulin biosynthesis and elevated insulin secretion from existing ß-cells and might prevent islet cell loss.


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Diabetes Mellitus Tipo 2/terapia , Insulina/biosíntesis , Leucocitos Mononucleares/trasplante , Trasplante de Células Madre/métodos , Adulto , Glucemia/análisis , Células de la Médula Ósea/citología , Trasplante de Médula Ósea , Péptido C/sangre , Femenino , Sangre Fetal/citología , Hemoglobina Glucada/análisis , Humanos , Insulina/sangre , Células Secretoras de Insulina/citología , Masculino , Persona de Mediana Edad , Células Madre/citología , Trasplante Autólogo , Resultado del Tratamiento
12.
Cytotherapy ; 16(7): 934-45, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24794183

RESUMEN

BACKGROUND: To evaluate the therapeutic efficacy of dendritic cells (DC) alone, cytokine-induced killer (CIK) cells alone and the combination of DC and CIK cells in the treatment of breast cancer, we performed a systemic review of the relevant published clinical studies, collectively referred to as DC-CIK cell therapy. METHODS: Six hundred thirty-three patients with breast cancer were assigned to cohorts, and a meta-analysis was conducted. RESULTS: The treatment of breast cancer with DC-CIK cells was associated with a significantly improved 1-year survival (P = 0.0001). The Karnofsky performance status scale of the patients treated with DC-CIK cells was significantly improved compared with that of the non-DC-CIK group (P < 0.0001). The percentage of T cells (CD3(+), CD4(+) and CD4(+)CD8(+)), CD16(+) monocytes, and CD3(+)CD56(+) natural killer T cells in the peripheral blood of cancer patients was significantly increased (P ≤ 0.05), whereas the percentage of CD4(+)CD25(+) regulatory T cells was not significantly decreased (P = 0.32) in the DC-CIK treatment group compared with the non-DC-CIK group. The levels of interleukin-2, interleukin-12, tumor necrosis factor-α, interferon-γ, and nucleolar organizer region protein in the peripheral blood of cancer patients, which reflect immune function, were significantly increased (P < 0.001) after DC-CIK cell treatment. Furthermore, after DC-CIK treatment, the average levels of the alpha-fetoprotein, cancer antigen embryonic antigen and carbohydrate antigen tumor markers were decreased (P < 0.00001). CONCLUSIONS: DC-CIK cell therapy markedly prolongs survival time, enhances immune function, and improves the efficacy of the treatment of breast cancer patients.


Asunto(s)
Neoplasias de la Mama/terapia , Células Asesinas Inducidas por Citocinas/trasplante , Células Dendríticas/trasplante , Inmunoterapia Adoptiva/métodos , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/patología , Ensayos Clínicos como Asunto , Femenino , Humanos , Inmunoterapia Adoptiva/efectos adversos
13.
J Am Heart Assoc ; : e035772, 2024 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-39470054

RESUMEN

BACKGROUND: Currently, there is a lack of evidence for the long-term bioprosthetic valve durability of patients with bicuspid aortic valve (BAV) following transcatheter aortic valve replacement (TAVR). METHODS AND RESULTS: This study aimed to evaluate hemodynamic outcome, structural valve deterioration, and bioprosthetic valve failure during long-term follow-up after TAVR in patients with BAV versus patients with tricuspid aortic valve (TAV). Patients with BAV and TAV who underwent TAVR between 2012 and 2020, with echocardiography followed for at least 3 years, were included. Baseline characteristics, long-term valve hemodynamic performance, structural valve deterioration, and bioprosthetic valve failure were compared between patients with BAV and TAV. A total of 170 patients with BAV and 145 patients with TAV were included. The mean duration of follow-up for patients with BAV and TAV was 5.2±1.8 and 5.0±1.7 years. No significant differences were observed in the rates of structural valve deterioration and bioprosthetic valve failure between patients with BAV and TAV: structural valve deterioration, BAV 20 (11.8%) versus TAV 16 (11.0%) at last follow-up (P=0.861); bioprosthetic valve failure, BAV 3 (1.8%) versus TAV 7 (4.8%) at last follow-up (P=0.196). More than moderate intravalvular aortic regurgitation (1.8% versus 4.8%, P=0.196) and paravalvular leak (6.5% versus 3.4%, P=0.305) were rare in both patients with BAV and patients with TAV. CONCLUSIONS: This study indicated satisfactory long-term valve durability of TAVR in patients with BAV. Comparable hemodynamic outcome, structural valve deterioration, and bioprosthetic valve failure could be achieved in patients with BAV and TAV during long-term follow-up after TAVR.

14.
Phys Rev Lett ; 108(5): 050501, 2012 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-22400918

RESUMEN

We propose a practical entanglement classification scheme for general multipartite pure states in arbitrary dimensions under local unitary equivalence by exploiting the high order singular value decomposition technique and local symmetries of the states. By virtue of this scheme, the method of determining the local unitary equivalence of n-qubit states proposed by Kraus is extended to the case for arbitrary dimensional multipartite states.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(10): 2814-8, 2011 Oct.
Artículo en Zh | MEDLINE | ID: mdl-22250562

RESUMEN

Due to the problem that the convex cone analysis (CCA) method can only extract limited endmember in multispectral imagery, this paper proposed a new endmember extraction method by spatial adaptive spectral feature analysis in multispectral remote sensing image based on spatial clustering and imagery slice. Firstly, in order to remove spatial and spectral redundancies, the principal component analysis (PCA) algorithm was used for lowering the dimensions of the multispectral data. Secondly, iterative self-organizing data analysis technology algorithm (ISODATA) was used for image cluster through the similarity of the pixel spectral. And then, through clustering post process and litter clusters combination, we divided the whole image data into several blocks (tiles). Lastly, according to the complexity of image blocks' landscape and the feature of the scatter diagrams analysis, the authors can determine the number of endmembers. Then using hourglass algorithm extracts endmembers. Through the endmember extraction experiment on TM multispectral imagery, the experiment result showed that the method can extract endmember spectra form multispectral imagery effectively. What's more, the method resolved the problem of the amount of endmember limitation and improved accuracy of the endmember extraction. The method has provided a new way for multispectral image endmember extraction.

16.
Radiat Res ; 196(2): 175-182, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-33979443

RESUMEN

A seed-loading device was designed and modeled using the Monte Carlo method to verify the biological effect of iodine-125 (125I) particles on blood vessels through animal experiments. The dose distribution characteristics of irradiated vessels were established by adjusting the design variables and geometry. The deviation between the actual value and the theoretical value was verified in vitro by the thermoluminescence dosimetry (TLD) method. After verification, the device was used to examine the biological effect of 125I irradiation of canine carotid arteries in two dogs (and one control dog) for 180 days. The hollow cylinder seed-loading device was constructed with an inner diameter of 0.5 cm and a length of 3.3 cm. When six seeds were loaded into a single layer, the source strength ratio of the intermediate layer to the edge layer was 0.7:1. When six layers of seeds were arranged at 0.45-cm intervals, the deviations between the maximum, minimum and mean energy fluence within 2.25 cm of the vessel wall were 2.19% and -4.12%, respectively, and -9% and 4%, respectively, when verified in vitro using TLD. The carotid arteries showed good tolerance to 0.56 kGy (range of 0.51-0.58 kGy) after 180 days of irradiation. In conclusion, this 125I seed-loading device overcomes the random distribution of seeds and lays an accurate radiophysical foundation for subsequent biological experiments. The preliminary results showed that the carotid artery has good tolerance to 0.56 kGy irradiation.


Asunto(s)
Arterias Carótidas/efectos de la radiación , Radioisótopos de Yodo/farmacología , Animales , Anisotropía , Arterias Carótidas/patología , Simulación por Computador , Perros , Humanos , Radioisótopos de Yodo/química , Método de Montecarlo , Fantasmas de Imagen , Prótesis e Implantes , Dosificación Radioterapéutica
17.
Zhonghua Jie He He Hu Xi Za Zhi ; 33(2): 123-7, 2010 Feb.
Artículo en Zh | MEDLINE | ID: mdl-20367953

RESUMEN

OBJECTIVE: to investigate the antitumor effects of tumstatin185-191 as a single agent or combination with cisplatin (DDP) on non-small lung cancer (NSCLC) cell lines A549. In addition, the changes of the protein kinase B(Akt) and extracellular regulated protein kinase (ERK) in cultured NSCLC cells treated by tumstatin185-191 and cisplatin were evaluated. METHODS: A549 cells were treated with tumstatin185-191 and cisplatin. Cell viability was assessed using the modified 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell apoptosis was measured by flow cytometry. The activation of Akt and Erk were evaluated by Western blotting. RESULTS: Tumstatin185-191 inhibited the proliferation of A549 and the IC(50) values of tumstatin 185-191 was 73.7 micromol/L. After cotreatment with 20 micromol/L tumstatin185-191, IC(50) values of cisplatin in A549 cells reduced from 5.2 micromol/L to 3.5 micromol/L, while 40 micromol/L tumstatin185-191 reduced from 5.2 micromol/L to 1.4 micromol/L. The early apoptosis rate was (19.34 +/- 0.97)% in the cotreatment group, (12.5 +/- 2.1)% in cisplatin group and (9.6 +/- 1.6)% in tumstatin185-191 group (F = 5.74, P < 0.01). The levels of phospho-Akt (p-Akt) and phospho-ERK (p-ERK) in the A549 cells were remarkably lower after being treated with tumstatin 185-191, while tumstatin 185-191 treatment whether alone, or in combination with cisplatin, had the similar effects on the protein levels of p-Akt and p-ERK in A549 cells. CONCLUSION: our data suggest that tumstatin185-191 might enhance the sensitivity of A549 cells to cisplatin. The effects of promoting apoptosis and downregulation of proliferation induced by tumstatin185-191 may be mediated through inactivation of the Akt and ERK pathways.


Asunto(s)
Adenocarcinoma/metabolismo , Autoantígenos/farmacología , Colágeno Tipo IV/farmacología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Adenocarcinoma/patología , Adenocarcinoma del Pulmón , Apoptosis , Autoantígenos/administración & dosificación , Línea Celular Tumoral/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cisplatino/administración & dosificación , Cisplatino/farmacología , Colágeno Tipo IV/administración & dosificación , Humanos , Neoplasias Pulmonares/patología
18.
Zhonghua Zhong Liu Za Zhi ; 31(8): 577-81, 2009 Aug.
Artículo en Zh | MEDLINE | ID: mdl-20021943

RESUMEN

OBJECTIVE: To investigate the effects and related mechanisms of Tumstatin 185-191 as a single agent or in combination with cisplatin on proliferation and apoptosis in a cisplatin-resistant human lung adenocarcinoma cell line A549-DDP cells. METHODS: A549-DDP cells were treated with Tumstatin185-191 and cisplatin at varying concentrations. Cell viability was assessed by a modified 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. 50% inhibiting concentration (IC(50)) values of the chemotherapeutic drugs were analyzed by MTT assay. Cell apoptosis was measured by flow cytometry. The activation of Akt and ERK was evaluated by Western blotting. RESULTS: Tumstatin185-191 inhibited the proliferation of A549-DDP cells and its IC(50) value was 80.25 micromol/L. After cotreatment with 20 micromol/L Tum185-191, the IC(50) value of cisplatin in A549-DDP cells reduced from 77.16 micromol/L to 57.97 micromol/L, the reverse index was 1.33, while with 40 micromol/L Tumstatin185-191 the IC(50) was reduced from 77.16 to 26.40 micromol/L and the reverse index was 2.92. The early apoptosis rate was 19.5% +/- 1.1% in the cotreatment group, while 13.3% +/- 1.5% in cisplatin group and 10.2% +/- 2.0% in Tum185-191 group (F = 4.09, P < 0.05). The levels of phospho-Akt (p-Akt) and phospho-ERK (p-ERK) in the A549-DDP cells were remarkably lower after treatment with Tumstatin 185-191. The Tumstatin 185-191 treatment alone or in combination with cisplatin had a similar effect on the protein levels of p-Akt and p-ERK in A549-DDP cells. CONCLUSION: Our data suggest that Tumstatin185-191 may promote apoptosis, downregulate proliferation and partly reverse the drug resistance of A549-DDP cells to cisplatin. The effects induced by Tum185-191 may be mediated through inactivation of the Akt and ERK pathways.


Asunto(s)
Adenocarcinoma/patología , Apoptosis/efectos de los fármacos , Autoantígenos/farmacología , Proliferación Celular/efectos de los fármacos , Colágeno Tipo IV/farmacología , Neoplasias Pulmonares/patología , Antineoplásicos/farmacología , Línea Celular Tumoral , Cisplatino/farmacología , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Fragmentos de Péptidos/farmacología , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo
19.
Zhonghua Jie He He Hu Xi Za Zhi ; 32(12): 931-4, 2009 Dec.
Artículo en Zh | MEDLINE | ID: mdl-20193355

RESUMEN

OBJECTIVE: To investigate the effect of activator protein-2alpha (AP-2alpha) on activation of cysteine proteases with aspartate specificity 3 (Caspase 3) and the apoptosis of vascular endothelial cells (ECV304) induced by cigarette smoke extract (CSE). METHODS: ECV304 were cultured in vitro, and those at the exponential growth phase were studied in experiments. The cells were cultured with 0.0%, 2.5%, 5.0%, 10.0%, 15.0%, and 20.0%CSE respectively for 24 h, and in another experiment, the cells were exposed to 5.0%CSE for 0, 6, 12, 18, 24, 36, and 48 h respectively. Then the cells were infected with different virus vectors or treated by 5%CSE alone for 24 h. Cell apoptosis, and proliferation were tested by Hoechst staining and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) respectively, while the expression of cleaved Caspase 3 and AP-2alpha induced by CSE were tested by Western blot. The effects of over-expression of AP-2alpha on ECV304 apoptosis and the expression of cleaved Caspase 3 were investigated by transfection, Hoechst staining and Western blot. RESULTS: Compared with the blank control group (0.630 +/- 0.086), the proliferation was significantly increased in 2.5% CSE group (0.754 +/- 0.109), while that was decreased in the 5.0%, 10.0%, 15.0% and 20.0% CSE groups in a concentration-dependent manner. The cell apoptosis rate induced by 5.0%CSE was increased in a time-dependent manner [from (5.0 +/- 1.0)% to (72.6 +/- 12.1)%], and the differences among the groups was significant (chi(2) = 1773.0, P < 0.01). The expressions of AP-2alpha (0.882 +/- 0.014) in 24 h CSE-treatment group was higher than that of the control group (0.635 +/- 0.005, t = 5.21, P < 0.01). Over-expression of AP-2alpha inhibited the cell apoptosis [the apoptosis rate was (0.9 +/- 0.4)%, (7.5 +/- 0.9)% respectively] and the expression of cleaved Caspase 3 (the ratio were 0.300 +/- 0.020, 0.484 +/- 0.025) induced by CSE (t = 6.96, 8.75, all P < 0.01). CONCLUSION: AP-2alpha was shown to inhibit the activation of Caspase 3 and the apoptosis of ECV304 induced by CSE.


Asunto(s)
Caspasa 3 , Fumar , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Células Endoteliales/metabolismo , Humanos , Humo , Nicotiana
20.
Zhonghua Jie He He Hu Xi Za Zhi ; 32(2): 128-32, 2009 Feb.
Artículo en Zh | MEDLINE | ID: mdl-19567186

RESUMEN

OBJECTIVE: To explore the effect of cyclooxygenase-2 on vascular endothelial cell apoptosis induced by cigarette smoke extract. METHODS: Human vascular endothelial cells (ECV-304) were cultured in vitro, and those at the exponential growth phase were studied in experiments. The experiment was completed through 3 steps: (1) ECV-304 cells were cultured with 0.0%, 0.5%, 1.0% and 5.0% CSE for 12 h. (2) ECV-304 cells were exposed to 5.0% CSE for 0, 3, 6, 9, 12 and 24 h. (3) Endothelial cells were treated by 5% CSE, together with different concentrations of selective COX-2 inhibitor celecoxib (0.0, 2.5, 5.0, 10.0, 20.0, 50.0 micromol/L concentrations) for 9 h. The cell apoptosis rate was tested by Hoechst staining and flow cytometry methods, and the expression of COX-2 protein by immunocytochemistry and Western blotting. RESULTS: CSE induced ECV-304 cell apoptosis and COX-2 expression in a dose-dependent manner. The apoptosis rate of ECV-304 cells with 5.0% CSE was the highest (5.40+/-0.39)%. CSE- induced COX-2 expression reached the highest level with 5.0% CSE (206.1+/-15.5), the differences being significant (F=90.03, 159.94, all P<0.05). Furthermore CSE induced both apoptosis rate and COX-2 expression time-dependently, with the apoptosis rate achieving the peak after 24 h (8.87+/-0.41)%, while COX-2 expression reached the highest level at 9 h. The selective COX-2 inhibitor celecoxib inhibited COX-2 protein expression partially and augmented cell apoptosis induced by CSE. CONCLUSIONS: CSE induces endothelial cell apoptosis and increases the expression of COX-2 protein in vascular endothelial cells. Celecoxib, the selective COX-2 inhibitor, reduces the expression of COX-2 protein and promotes cell apoptosis induced by CSE in vascular endothelial cells. COX-2 may play an important role in protecting development of CSE-associated apoptosis of endothelial cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Inhibidores de la Ciclooxigenasa 2/farmacología , Ciclooxigenasa 2/metabolismo , Pirazoles/farmacología , Humo/efectos adversos , Sulfonamidas/farmacología , Celecoxib , Línea Celular , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Humanos , Nicotiana
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