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1.
J Clin Nurs ; 33(5): 1709-1723, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38156732

RESUMEN

AIMS: To identify studies and the content of the interventions that have facilitated the implementation of pressure injury (PI) prevention measures in nursing home settings. DESIGN AND METHOD: A scoping review methodology was employed. The author has carried out the following steps successively: Identified this scoping review's questions, retrieved potentially relevant studies, selected relevant studies, charted the data, summarised the results, and consulted with stakeholders from nursing homes in China. DATA SOURCES: Six electronic databases and three resources of grey literature-PubMed, CINAHL, Web of Science Core Collection, Embase, Cochrane Central Register of Controlled Trials, Psych INFO, Open Grey, MedNar, ProQuest Dissertations, and Theses Full Texts were searched from January 2002 through May 2022. RESULTS: Forty articles were included, among which the primary interventions were quality improvement, training and education, evidence-based practice, device-assisted PI prophylaxis, nursing protocols, and clinical decision support systems. Twenty-three outcome indicators were summarised in 40 articles, which included 10 outcome indicators, seven process indicators, and six structural indicators. Furthermore, only five articles reported barriers in the process of implementing interventions. CONCLUSION: The common interventions to promote the implementation of PI prevention measures in nursing homes are quality improvement, training, and education. Relatively limited research has been conducted on evidence-based practice, clinical decision support systems, device-assisted PI prophylaxis, and nursing protocols. In addition, there is a paucity of studies examining the impediments to implementing these measures and devising targeted solutions. Therefore, it is recommended that future studies include analysis and reporting of barriers and facilitators as part of the article to improve the sustainability of the intervention. IMPACT: This article reminds nursing home managers that they should realise the importance of implementation strategies between the best evidence of PI prevention and clinical practice. Also, this review provides the types, contents, and outcome indicators of these strategies for managers of nursing homes to consider what types of interventions to implement in their organisations. TRIAL AND PROTOCOL REGISTRATION: The protocol of this scoping review was published as an open-access article in June 2022 (Yang et al., 2022).


Asunto(s)
Úlcera por Presión , Humanos , Úlcera por Presión/prevención & control , Casas de Salud , China
2.
Genet Mol Res ; 15(2)2016 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-27421005

RESUMEN

Previous studies examining the association between interleukin-6 (IL-6) -174G/C polymorphism and psoriasis risk have produced inconsistent results. The aim of this study was to offer a comprehensive review of the association between IL-6 -174G/C polymorphism and psoriasis risk through a meta-analysis. Literature search of PubMed and Embase databases was conducted to identify all eligible studies published before October 29, 2015. Four case-control studies involving 651 psoriasis cases and 552 controls were included in this meta-analysis. Data were extracted, and pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the associations. Combined analysis revealed a significant association between this polymorphism and psoriasis risk under the recessive model (OR = 1.69, 95%CI = 1.12-2.55, P = 0.013 for GG vs GC + CC), and the heterozygous comparison model (OR = 1.70, 95%CI = 1.29-2.23, P < 0.001 for GG vs GC). However, no significant association was observed under the allelic model (OR = 1.37, 95%CI = 0.99-1.89, P = 0.060 for G vs C), the dominant model (OR = 1.25, 95%CI = 0.92-1.71, P = 0.152 for GG + GC vs CC), and the homozygote comparison model (OR = 1.62, 95%CI = 0.79-3.32, P = 0.186 for GG vs CC). We conclude that the IL-6 -174G/C polymorphism contributes to psoriasis risk. However, further studies should be performed to validate our results.


Asunto(s)
Interleucina-6/genética , Psoriasis/genética , Alelos , Estudios de Casos y Controles , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Interleucina-6/inmunología , Polimorfismo de Nucleótido Simple , Psoriasis/inmunología , Factores de Riesgo
3.
Genet Mol Res ; 14(2): 3869-76, 2015 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-25966157

RESUMEN

Previous studies investigating the association between methylenetetrahydrofolate reductase (MTHFR) 677C/T polymorphisms and psoriasis risk have reported inconsistent results. The present meta-analysis aimed to comprehensively evaluate the association between MTHFR 677C/T polymorphism and psoriasis risk. The studies regarding the association between MTHFR 677C/T polymorphism and psoriasis risk were retrieved from the PubMed, Embase, Web of Science, Chinese National Knowledge Infrastructure, and Chinese Biomedical databases. Data were extracted and statistical analysis was performed with the program STATA 12.0. A total of seven studies involving 1290 psoriasis cases and 1068 healthy controls were retrieved. Combined analysis showed that there was no significant difference in MTHFR 677C/T genotype distribution between psoriasis and control subjects in the comparisons C vs T, CC vs CT + TT, CC + CT vs TT, CC vs TT, and CC vs CT [respectively: odds ratio (OR) = 0.98, 95% confidence interval (CI) = 0.76-1.26, P = 0.882; OR = 1.11, 95%CI = 0.81-1.51, P = 0.526; OR = 0.79, 95%CI = 0.53-1.19, P = 0.261; OR = 0.88, 95%CI = 0.51-1.52, P = 0.648; OR = 1.19, 95%CI = 0.90-1.58, P = 0.217]. Subgroup analysis by ethnicity also showed no significant association between MTHFR 677C/T polymorphism and psoriasis risk in both Asian and Caucasian populations. In conclusion, this meta-analysis indicates that MTHFR 677C/T polymorphism may not be associated with psoriasis risk.


Asunto(s)
Predisposición Genética a la Enfermedad , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Polimorfismo Genético , Psoriasis/genética , Humanos
4.
Genet Mol Res ; 14(3): 9595-603, 2015 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-26345892

RESUMEN

Several case-control studies have been conducted to investigate the association between Interleukin-21 (IL-21) polymorphisms and systemic lupus erythematosus (SLE) susceptibility, and most of the studies focused on IL-21 rs907715 and rs2221903 polymorphisms. Given the inconsistent results from these studies, the present meta-analysis aimed to obtain a more precise estimate of the association between IL-21 rs907715 and rs2221903 polymorphisms and SLE. Studies regarding these specific polymorphisms and SLE were retrieved from PubMed, Embase, Web of Science, CNKI, and CBM. Data were extracted and meta-analysis was performed using the STATA 12.0 software. For the IL-21 rs907715 polymorphism, seven sets of comparisons involving 7977 SLE cases and 8097 healthy controls were considered. Results showed that there were significant differences in the IL-21 rs907715 genotype distribution between SLE patients and healthy controls in the comparisons of all genetic models. Upon stratified analysis by ethnicity, a similar result was found in the Caucasian and African-American population. For the IL-21 rs2221903 polymorphism, seven sets of comparisons involving 7990 SLE cases and 8098 healthy controls were considered. Results showed that there were significant differences in the IL-21 rs2221903 genotype distribution between SLE patients and healthy controls in the comparisons of GG versus AA and GG versus GA+AA. Upon stratified analysis by ethnicity, a similar result was found in the Caucasian population. This meta-analysis suggests that the both IL-21 rs907715 and rs2221903 polymorphisms may be associated with SLE susceptibility. As current evidence remains limited, further studies are needed to warrant the association between IL-21 rs907715 and rs2221903 polymorphisms and SLE susceptibility.


Asunto(s)
Predisposición Genética a la Enfermedad , Interleucinas/genética , Lupus Eritematoso Sistémico/genética , Polimorfismo de Nucleótido Simple , Alelos , Estudios de Casos y Controles , Frecuencia de los Genes , Estudios de Asociación Genética , Genotipo , Humanos , Oportunidad Relativa , Sesgo de Publicación
5.
Genet Mol Res ; 14(4): 17296-304, 2015 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-26681224

RESUMEN

Several case-control studies have been conducted to investigate the association between the tumor necrosis factor-α (TNF-α)-308G/A polymorphism and vitiligo risk. However, the results of these studies are inconsistent; therefore, we attempted to comprehensively evaluate the association between TNF-α-308G/A polymorphism and vitiligo risk via a meta-analysis. Studies reporting the association between TNF-α-308G/A polymorphism and vitiligo risk were retrieved from PubMed and EmBase databases. Data were extracted from these studies and the pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the association. Six case-control studies including 1391 vitiligo cases and 2455 control subjects were included in this meta-analysis. The overall results showed the lack of a significant difference in TNF-α-308G/A genotype distribution between the patients and controls when the G allele and GG, GG + GA, GG, and GG genotypes were compared against the A allele and the GA + AA, AA, AA, and GA genotypes, respectively (ORs = 0.65, 0.53, 0.63, 0.41, 0.55; 95%CI = 0.35-1.23, 0.24-1.18, 0.10-4.09, 0.08-1.97, 0.25-1.21; P = 0.188, 0.121, 0.627, 0.264, 0.135, respectively). This meta-analysis suggests that the TNF-α-308G/A polymorphism may not be associated with vitiligo risk. As few studies are available in this field and current evidence remains limited, these results must be corroborated with well-designed and larger studies in the future.


Asunto(s)
Alelos , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Factor de Necrosis Tumoral alfa/genética , Vitíligo/genética , Estudios de Casos y Controles , Estudios de Asociación Genética , Genotipo , Humanos , Oportunidad Relativa , Sesgo de Publicación , Riesgo , Vitíligo/epidemiología
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 43(4): 586-590, 2022 Apr 10.
Artículo en Zh | MEDLINE | ID: mdl-35443317

RESUMEN

Objective: To explore the suitable teaching mode of epidemiology for postgraduates, so as to provide techniques for improving and enhancing the teaching quality. Methods: The course was divided into three stages according to the teaching progress, which was, traditional teaching, traditional teaching and case discussion, online learning and case discussion. The test scores in three stages were compared respectively, and the students' willingness to teaching methods was investigated by questionnaire. Results: The scores of 214 students showed an upward trend in three stages, and the differences were statistically significant (P<0.001). Most students paid more attention to the knowledge systematization and important knowledge. Most students proposed that the teaching time between theoretical knowledge and case discussion should be evenly distributed. More students chose Chinese literature related to their major as teaching cases. Most students believed that case discussion improved the skills of self-study and communication. Conclusion: The epidemiology course for postgraduate should integrate the traditional teaching and case discussion, with online learning as a supplementary, and take effective methods to evaluate, so as to improve the teaching quality of postgraduate.


Asunto(s)
Estudiantes , Enseñanza , Humanos , Encuestas y Cuestionarios
8.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(2): 343-350, 2021 Feb 10.
Artículo en Zh | MEDLINE | ID: mdl-33626626

RESUMEN

Objective: To explore the association between statins and colorectal cancer and provide evidence for the prevention of colorectal cancer. Methods: Literatures about statins and colorectal cancer published from January 2000 to January 2020 were retrieved from CNKI, Wanfang data, PubMed and Cochrane Library database. The literatures which met the inclusion criteria were collected, and the Newcastle-Ottawa Scale and Jadad score were used to assess the studies. Meta-analysis was performed with statistical software Revman 5.0 and Stata 12.1. Results: A total of 31 studies, involving more than 1.62 million subjects, were included in the analysis. The case-control study (RR=0.93, 95%CI: 0.88-0.98), the cohort study (RR=0.75, 95%CI: 0.63-0.88) and the randomized controlled trial (RR=0.79, 95%CI: 0.65-0.97) showed moderate protective effect of statins. Using statin <5 years (RR=0.86, 95%CI: 0.76-0.96), average daily dosage ≥34 mg (RR=0.81, 95%CI: 0.66-0.98) and lipid-soluble statins (RR=0.86, 95%CI: 0.74-0.99) also had preventive effect on colorectal cancer; while lovastatin (RR=1.07, 95%CI: 1.00-1.14) increased the risk of colorectal cancer. Conclusion: Statins have protective effect on colorectal cancer.


Asunto(s)
Neoplasias Colorrectales , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Estudios de Casos y Controles , Estudios de Cohortes , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/prevención & control , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto
9.
Zhonghua Shao Shang Za Zhi ; 36(7): 623-626, 2020 Jul 20.
Artículo en Zh | MEDLINE | ID: mdl-32842417

RESUMEN

Scar is a kind of skin fibroproliferative disease characterized by excessive repair of skin tissue and disorganized deposition of extracellular matrix resulting from deep dermal injury caused by burns or trauma. Scar is accompanied by symptoms such as itching and pain, which could lead to appearance damage and psychological disorders, and is one of the common diseases in burns and plastic surgery clinics. Currently, transplantation of adipose tissue and components is considered as one of the most cutting-edge treatments for scar. Adipose components transplantation includes transplantation of nanofat, adipose-derived stem cell matrix gel, stromal vascular fraction, and adipose-derived stem cell. More and more studies showed that adipose tissue and components possess the functions of tissue regeneration, extracellular matrix remodeling, and anti-fibrosis, which could improve the appearance and symptoms of scar by local transplantation. Therefore, this paper reviews the effects of adipose tissue and components transplantation on scar treatment, aiming to provide theoretical reference for adipose treatment of scar.


Asunto(s)
Tejido Adiposo , Cicatriz , Adipocitos , Humanos , Piel , Cicatrización de Heridas
10.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 31(20): 1589-1592, 2017 Oct 20.
Artículo en Zh | MEDLINE | ID: mdl-29797956

RESUMEN

Objective:To study the effect of monrustet on fractional exhaled nitric oxide and inflammatory cytokines in the elderly with bronchial asthma combined obstructive sleep apnea hypopnea syndrome.Method:150 cases diagnosed as asthma were enrolled in this study. The patients were divided into bronchial asthma combined with OSAHS (n=72)and bronchial asthma (n=78). According to the different treatment methods , patients were divided into observation group and control group. Two groups were given common treatment with inhaled corticosteroids, and the observation group was taken orally montrast 10mg/night additionally. The fractional exhaled nitric oxide was detected before and after treatment. Serum were collected for detection of tumor necrosis factor alpha (TNR-α), Creactive protein (CRP) and interleukin 6 (IL-6), according to the sleep monitoring results, the sleep apnea low ventilation index (AHI) was calculated, and the changes of FeNO level,CRP,TNR-α,IL-6 and AHI were analyzed in the two groups.Result:Before treatment, the gender, age, degree of disease, FeNO level,TNR-α, CRP,IL-6 and AHI differences were not statistically significant in the two groups (P>0.05).After treatment, both groups of FeNO, TNR-α,CRP,IL-6 and AHI decreased before treatment (P < 0.05).The observation group was lower than the control group, and the difference was statistically significant (FeNO level, AHIP< 0.01,TNR-α, CRP,IL-6 P< 0.05).Conclusion::Montelukast can reduce the FeNO level, the expression of TNR-α, CRP, and IL-6 of patients of bronchial asthma combined with OSAHS. Further improvement of the patient's condition, and provide reference value for the clinical medicine of patients with asthma.


Asunto(s)
Acetatos/uso terapéutico , Asma/tratamiento farmacológico , Óxido Nítrico/metabolismo , Quinolinas/uso terapéutico , Apnea Obstructiva del Sueño/tratamiento farmacológico , Acetatos/farmacología , Asma/complicaciones , Asma/metabolismo , Pruebas Respiratorias , Ciclopropanos , Citocinas/metabolismo , Espiración , Humanos , Quinolinas/farmacología , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/metabolismo , Sulfuros
11.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 31(21): 1681-1683, 2017 Nov 05.
Artículo en Zh | MEDLINE | ID: mdl-29798127

RESUMEN

Objective:To study effects of ketotifen on fractional exhaled nitric oxide in patients with combined allergic rhinitis and asthma syndrome.Method:One hundred and twelve patients with asthma were selected from department of respiration, Affiliated Hospital of North China University of science and technology from January 2016 to 2017 in March. Eighty-four patients with allergic rhinitis were selected as the subjects, Randomly divided into two groups,including observed group(n=42) and control group(n=42).The control group was treated with antitussive,expectorant and inhaled corticosteroids, while the observed group in the control group combined with ketotifen 1 mg 2/ day oral treatment,the changes of FeNO and IL-17 in the two groups were compared after one month treament.Result:Before treatment, two groups of patients in general IL-17 and fractional exhaled nitric oxide ware no significant difference(P> 0.05).After treatment, compared to the control group, the observed group was significantly more effective,the difference was statistically significant(P <0.05);fractional exhaled nitric oxide in treatment group were lower than those in control group, the difference was statistically significant(P<0.05,P< 0.01).And the observed group was lower than the control group, and the differences were statistically significant,t(P<0.05).Conclusion:Ketotifen significantly reduce the FeNO of allergic rhinitis and asthma syndrome, reduce airway inflammation.


Asunto(s)
Asma/tratamiento farmacológico , Cetotifen/farmacología , Óxido Nítrico , Rinitis Alérgica/tratamiento farmacológico , Pruebas Respiratorias , China , Humanos
12.
SAR QSAR Environ Res ; 11(2): 117-31, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10877473

RESUMEN

It is proposed for the first time a method of prediction of the programmed-temperature retention times of components of naphthas in capillary gas chromatography using artificial neural networks. People are used to predict the programmed-temperature retention time using many formulas such as the integral formula, which requires that four parameters must be determined by calculation or experiments. However the results obtained by the formula are not so good to meet the demand of industry. In order to predict retention time accurately and conveniently, artificial neural networks using five-fold cross-validation and leave-20%-out methods have been applied. Only two parameters: density and isothermal retention index were used as input vectors. The average RMS error for predicted values of five different networks was 0.18, whereas the RMS error of predictions by the integral formula was 0.69. Obviously, the predictions by neural networks were much better than predictions by the formula, and neural networks need fewer parameters than the formula. So neural networks can successfully and conveniently solve the problem of predictions of programmed-temperature retention times, and provide useful data for analysis of naphthas in petrochemical industry.


Asunto(s)
Naftalenos/metabolismo , Redes Neurales de la Computación , Industria Química , Cromatografía de Gases , Predicción , Modelos Teóricos , Sensibilidad y Especificidad , Temperatura
14.
J Hazard Mater ; 174(1-3): 137-43, 2010 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-19800169

RESUMEN

The biosorption of Cu(II) onto chestnut shell, a residue of the food processing industry, in a batch adsorber has been studied. Equilibrium isotherms, kinetic data, and thermodynamic parameters have been evaluated. Equilibrium data agreed well with Langmuir isotherm and Redlich-Peterson isotherm models. The adsorption capacity of chestnut shell for Cu(II) was determined with the Langmuir model and was found to be 12.56 mg g(-1) at 293K. The kinetic data were found to follow the pseudo-second-order model. Intra-particle diffusion is not the sole rate-controlling factor. Gibbs free energy was spontaneous for all interactions, and the adsorption process exhibited exothermic enthalpy values. Chestnut shell was shown to be a promising biosorbent for Cu(II) removal from aqueous solutions.


Asunto(s)
Cobre/química , Industria de Alimentos , Residuos Industriales , Nueces , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica
15.
Zhongguo Yao Li Xue Bao ; 13(2): 153-6, 1992 Mar.
Artículo en Zh | MEDLINE | ID: mdl-1350880

RESUMEN

Ip methoxamine (Met), norepinephrine (NE), xylazine (Xyl), and clonidine (Clo) produced dose-related reversal of ptosis induced by reserpine. These agonists had equivalent Emax values, however, the order of potency was: Clo greater than Met approximately NE greater than Xyl. Met-induced antiptotic action was competitively inhibited by prazosin (Pra) (apparent pA2 = 6.86), but not by idazoxan (Ida); Xyl-induced antiptotic action was competitively inhibited by Ida (apparent pA2 = 6.39), but inhibited by Pra in a noncompetitive manner. These results suggested that the eyelids of mice had both alpha-1 and alpha-2 adrenoceptors. In mice lacrimal gland, Met, and NE elicited dose-related lacrimal secretions, however, Xyl and Clo had no such reaction. Lacrimal secretions elicited by Met or NE were inhibited by Pra, but not by Ida. These results suggested that the lacrimal gland of mice had only alpha-1 adrenoceptor.


Asunto(s)
Agonistas alfa-Adrenérgicos/farmacología , Antagonistas Adrenérgicos alfa/farmacología , Párpados/efectos de los fármacos , Aparato Lagrimal/efectos de los fármacos , Receptores Adrenérgicos alfa/efectos de los fármacos , Animales , Femenino , Masculino , Ratones , Lágrimas/metabolismo
16.
Exp Cell Res ; 263(1): 173-82, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11161716

RESUMEN

Vascular endothelial growth factor (VEGF)-A stimulates formation of new blood vessels (angiogenesis). This process includes migration of endothelial cells from the preexisting vessel toward the source of the growth factor. We show that VEGF-A-induced migration of porcine aortic endothelial cells expressing VEGF receptor-2 (VEGFR-2) is dependent on activation of phosphoinositide 3-kinase (PI3-kinase). There is no direct interaction between VEGF receptor-2 and PI3-kinase; instead PI3-kinase is activated downstream of focal adhesion kinase (FAK) in VEGF-A-stimulated cells. Thus, VEGF-A stimulation leads to complex formation between FAK and PI3-kinase and overexpression of dominant-negative FAK decreases VEGF-A-induced PI3-kinase activation. FAK activation by VEGF-A increases with increasing concentration of growth factor, without apparent collapse of the cytoskeleton, in contrast to the effect of platelet-derived growth factor. FAK activation is mediated via the C-terminal tail of VEGFR-2 and loss of VEGF-A-induced FAK activation in cells expressing mutant VEGFR-2 correlates with loss of migration capacity. These data show that VEGF-A-induced FAK and PI3-kinase activation are required for migration of cells expressing VEGFR-2, via a pathway independent of direct interaction with the receptor.


Asunto(s)
Movimiento Celular , Factores de Crecimiento Endotelial/farmacología , Endotelio Vascular/efectos de los fármacos , Linfocinas/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Transducción de Señal/fisiología , Secuencia de Aminoácidos , Animales , Aorta/citología , Células Cultivadas , Medio de Cultivo Libre de Suero , Proteínas del Citoesqueleto/metabolismo , Endotelio Vascular/citología , Endotelio Vascular/fisiología , Activación Enzimática , Proteína-Tirosina Quinasas de Adhesión Focal , Datos de Secuencia Molecular , Paxillin , Fosfoproteínas/metabolismo , Fosforilación , Factor de Crecimiento Derivado de Plaquetas/genética , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Pruebas de Precipitina , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptores de Factores de Crecimiento/metabolismo , Receptores de Factores de Crecimiento Endotelial Vascular , Porcinos , Transfección , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
17.
J Biol Chem ; 274(20): 14455-63, 1999 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-10318871

RESUMEN

SHP-2 is a ubiquitously expressed Src homology-2-containing cytosolic tyrosine phosphatase that binds to and becomes tyrosine-phosphorylated by the activated platelet-derived growth factor receptor-beta (PDGFR-beta). Removal of the binding site on the receptor, by mutation of Tyr1009 to Phe1009 (denoted Y1009F), led to loss of PDGF-stimulated phosphatase activity in cells expressing the mutated receptor, and these cells failed to form membrane edge ruffles and to migrate toward PDGF. Furthermore, treatment with phosphatase inhibitors phenylarsine oxide (PAO) and orthovanadate led to loss of PDGF-stimulated phosphatase activity and attenuated PDGF-stimulated migration of wild type PDGFR-beta cells. Treatment of wild type PDGFR-beta cells with combinations of PAO or orthovanadate and phosphatidylinositol 3-kinase inhibitors wortmannin or LY294002 resulted in a synergistic inhibition of PDGFR-beta-mediated cell migration. PDGF stimulation of wild type PDGFR-beta cells led to induction of p125 focal adhesion kinase (FAK) activity at low concentrations of the growth factor and a decrease at higher concentrations. In the mutant Y1009F cells and in wild type PDGFR-beta cells treated with PAO and orthovanadate, FAK activity was not increased in response to PDGF. These results suggest that SHP-2 activity is involved in regulation of FAK activity and thereby of cell migration through PDGFR-beta, independently of phosphatidylinositol 3-kinase.


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Movimiento Celular/efectos de los fármacos , Factor de Crecimiento Derivado de Plaquetas/farmacología , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Dominios Homologos src , Animales , Becaplermina , Células Cultivadas , Relación Dosis-Respuesta a Droga , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal , Péptidos y Proteínas de Señalización Intracelular , Factor de Crecimiento Derivado de Plaquetas/administración & dosificación , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Proteína Tirosina Fosfatasa no Receptora Tipo 6 , Proteínas Proto-Oncogénicas c-sis , Conejos , Receptor beta de Factor de Crecimiento Derivado de Plaquetas , Receptores del Factor de Crecimiento Derivado de Plaquetas/metabolismo , Proteínas Tirosina Fosfatasas con Dominio SH2 , Porcinos
18.
Angiogenesis ; 3(4): 371-80, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-14517417

RESUMEN

Angiogenesis involves endothelial cell invasion and migration into the surrounding tissue where cells differentiate, to form new lumen-containing vessels. We have investigated the role of phosphoinositide 3-kinase (PI3-kinase) in vascular endothelial growth factor (VEGF)- and fibroblast growth factor (FGF)-induced angiogenesis. Angiogenesis in vivo in chick embryos was inhibited by treatment with the PI3-kinase inhibitors wortmannin and LY294002. Stimulation of primary bovine capillary endothelial (BCE) cells with FGF-2, VEGF-A(165), or a combination of the two induced PI3-kinase activity in vitro and subsequent activation of the serine/threonine kinase Akt. The combination of FGF-2 and VEGF-A(165) led to an additive response. Activation of PI3-kinase was strictly required for FGF-2- and VEGF-A(165)-induced migration and DNA synthesis of BCE cells. Tubular morphogenesis was unaffected by treatment with wortmannin or LY294002, but survival of the tubular structures was dependent on PI3-kinase activity. VEGF-A(165) and FGF-2 induced increased stability of the tubular structures in a synergistic manner. These data indicate that PI3-kinase activity is required for migration, mitogenicity and survival but not for differentiation of endothelial cells during angiogenesis.

19.
Zhongguo Yao Li Xue Bao ; 18(2): 140-2, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10072966

RESUMEN

AIM: To study the mechanisms of captopril (Cap) and enalaprilat (Ena) protective effects on hypoxic and reoxygenated cardiac myocytes. METHODS: Using fluorescent probes Fura 2-AM, BCECF/AM, SBFI/AM combined with computer image processing techniques to measure intracellular ion concentrations. RESULTS: [Ca2+]i (165 +/- 8 nmol.L-1) and [Na+]i (9.2 +/- 0.8 mmol.L-1) were higher but [pH]i (6.7 +/- 0.3) was lower in hypoxic and reoxygenated myocytes (196 +/- 14 nmol.L-1, 9.3 +/- 1.3 mmol.L-1, 6.61 +/- 0.19, respectively) than in normal ones. Cap and Ena reduced [Ca2+]i (149 +/- 11 and 152 +/- 10 nmol.L-1 respectively) and intracellular acidosis (7.11 +/- 0.22 and 7.2 +/- 0.4, respectively) during hypoxia. Cap also decreased [Na+]i in hypoxic myocytes (8.1 +/- 0.9 mmol.L-1). During reoxygenation, Cap decreased [Ca2+]i and [Na+]i but Ena had no significant effect on them. Cap or Ena had no additive effect when combined with verapamil (Ver). CONCLUSION: Cap and Ena protected hypoxic and reoxygenated cardiomyocytes, but the mechanisms were not the same.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Calcio/metabolismo , Captopril/farmacología , Enalaprilato/farmacología , Miocardio/metabolismo , Sodio/metabolismo , Animales , Bloqueadores de los Canales de Calcio/farmacología , Hipoxia de la Célula , Concentración de Iones de Hidrógeno , Miocardio/citología , Ratas , Ratas Wistar , Verapamilo/farmacología
20.
J Cardiovasc Pharmacol ; 34(5): 683-9, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10547084

RESUMEN

Pentoxifylline (PTX) is a phosphodiesterase inhibitor used in the treatment of peripheral vascular disease, and this agent can suppress inflammatory vascular damage. Inflammation has been implicated in vascular lesion formation, and we examined the effects of PTX in a model of arterial injury. Sprague-Dawley rats were treated with intraperitoneal PTX (75 mg/kg/day) or saline starting 3 days before carotid balloon injury, and killed 24 h or 14 days later. Carotid arteries were analyzed by cross-sectional morphometry, immunostaining for proliferating cell nuclear antigen (PCNA) and subjected to terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL). Moreover, the effects of PTX on vascular smooth-muscle cell (VSMC) migration and production of collagen types I, IV, and VI were examined in vitro. At 14 days after balloon injury, PTX reduced the neointimal area (0.074+/-0.001 vs. 0.172+/-0.003 mm2; p<0.001), media area (0.143+/-0.001 vs. 0.176+/-0.001 mm2; p<0.01), intima/media ratio (0.50+/-0.02 vs. 0.99+/-0.12; p<0.001), and total vessel area (0.601+/-0.010 vs. 0.744+/-0.011 mm2; p<0.01). The lumen area, PCNA expression, and TUNEL were similar in the two treatment groups, whereas the neointimal cell density was increased by PTX (3,476+/-504 cells/mm2 vs. 2,215+/-232 cells/mm2; p<0.05). In vitro, PTX inhibited VSMC production of collagen type I in a concentration-dependent manner and did not influence VSMC migration. We conclude that PTX inhibits neointimal formation and induces constrictive vascular remodeling in the rat model of balloon injury by mechanisms involving decreased VSMC collagen type I production.


Asunto(s)
Traumatismos de las Arterias Carótidas/patología , Pentoxifilina/farmacología , Inhibidores de Fosfodiesterasa/farmacología , Túnica Íntima/efectos de los fármacos , Túnica Íntima/patología , Vasoconstricción/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Presión Sanguínea/efectos de los fármacos , Traumatismos de las Arterias Carótidas/etiología , División Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Colágeno/biosíntesis , Modelos Animales de Enfermedad , Masculino , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Ratas , Ratas Sprague-Dawley
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