Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Más filtros











Intervalo de año de publicación
1.
Adv Mater ; : e2408475, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235588

RESUMEN

Compact batteries and electronic devices offer a plethora of advantages, including space optimization, portability, integration capability, responsiveness, and reliability. These attributes are crucial technical enablers for the design and implementation of various electronic devices and systems within scientific exploration. Thus, the group harnesses additive manufacturing technology, specifically utilizing five-axis curved-surface multi-material printing equipment, to fabricate aqueous zinc-ion batteries with tungsten-doped manganese dioxide cathode for enhanced adaptability and customization. The five-axis linkage motion system facilitates shorter ion transportation paths for compact batteries and ensures precise and efficient molding of non-developable curved surfaces. Afterward, the compact cell is integrated with a printed nano-silver serpentine resistor temperature sensor, and an integrated functional circuit is created using intense-pulse sintering. Incorporating an emitting Light Emitting Diode (LED) allows temperature measurement through variations in LED brightness. The energy storage module with a high degree of conformity on the carrier surface has the advantages of small size and improved space utilization. The capability to produce Zinc-ion batteries (ZIBs) on curved surfaces presents new avenues for innovation in energy storage technologies, paving the way for the realization of flexible and conformal power sources.

2.
Sensors (Basel) ; 22(3)2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35161681

RESUMEN

In some applications of piezoelectric three-dimensional inkjet printing, the materials used are power-law fluids as they are shear thinning. Their time-varying viscosities affect the droplet formation, which is determined by the volume flow rate at the nozzle outlet. To obtain a fine printing effect, it is necessary to present a driving waveform design method that considers the shear-thinning viscosities of materials to control the volume flow rate at the nozzle outlet, which lays the foundation for the single and stable droplet generation during the printing process. In this research, we established the relationship between the driving waveform and the volume flow rate at the nozzle outlet by modifying a model that describes the inkjet mechanism of power-law fluid. The modified model was used to present a driving waveform design method based on iterative learning control. The iterative learning law of the method was designed based on the gradient descent algorithm and demonstrated its convergence. The driving waveform design method was verified to be practical and feasible by implementing drop generation experiments.

3.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-751710

RESUMEN

Hippo signaling pathway plays a significant role in the development of colorectal cancer,and acts as an important regulatory pathway which regulates cell proliferation and cell differentiation.Multiple proteins and genes in Hippo signaling pathway,especially the downstream YAP protein,play important roles in the occurrence,metastasis,drug resistance and recurrence of colorectal cancer.YAP and other related genes can be used as targeted markers for predicting drug resistance to colorectal cancer.Hippo signaling pathway gene network can be used as targeted therapy or combination therapy,thus providing new ideas for the treatment of colorectal cancer.

4.
Journal of Chinese Physician ; (12): 1151-1154,1158, 2018.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-705963

RESUMEN

Objective To analyze and compare the demographic characteristics and clinical features of patients with reflux esophagitis (RE) and non-erosive reflux disease (NERD),so as to appraise their different pathogenesis and effective treatment.Methods 127 patients with RE and 80 patients with NERD were enrolled and asked to complete the questionnaires.The general situation,living habits,typical esophageal symptoms,extra esophageal symptoms and the comorbidities were recorded in the two groups.Results There were more male patients in RE group,and more female patients in NERD group (P <0.05).There were more patients engaged in mental work in RE group,and NERD group had more physical workers (P < 0.05).Compared with NERD,patients with RE were fatter and had more alcohol consumption (P < 0.05).The proportion of patients with abnormal mental disorders in NERD group was significantly higher than that in RE group (P < 0.05).NERD patients were more likely to incorporate irritable bowel syndrome (IBS) (P < 0.05).RE patients were more likely to suffer from hiatal hernia (P < 0.05).The incidence of anti-acid,chest pain,pharyngeal foreign body symptoms was higher in the NERD group (P < 0.05).Conclusions The demographic characteristics,living habits,mental and psychological factors,esophageal symptoms,extra esophageal symptoms and comorbidities in patients with NERD or RE are different.These results suggest that there are different pathogenesis between RE and NERD.

5.
Chinese Traditional Patent Medicine ; (12): 1427-1430, 2017.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-617206

RESUMEN

AIM To study the chemical constituents from twigs of Trigonostemon lutescens Y.T.Chang et J.Y.Liang.METHODS The ethyl acetate fraction of 95% ethanol extract from T.lutescens twigs was isolated and purified by silica,Sephadex LH-20 and MCI column,then the structures of obtained compounds were identified by physicochemical properties and spectral data.RESULTS Ten compounds were isolated and elucidated as 3-O-acetyloleanolic acid (1),methyl 3-acetoxy-12-enly-oleanen-28-oate (2),taraxerone (3),spiciflorin (4),simiarenol (5),β-sitosterol palmitate (6),3,3',4-tri-O-methylellagic acid (7),β-sitosterol (8),stigamasterol (9),palmitic acid (10).CONCLUSION Compounds 1-6 are isolated from genus Trigonostemon for the first time,compounds 7 and 9 are first obtained from this plant.

6.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-509055

RESUMEN

[ ABSTRACT] Interstitial cells of Cajal ( ICC) is the pacemaker in the gastrointestinal tract , which is closely as-sociated with the formation of slow wave and the regulation of gastrointestinal motility .As the pacemaker of gastrointestinal tract, the activation of pacing signal is triggered by the local calcium oscillation in the ICC .The change of calcium concen-tration can activate many relevant ion channels , such as NSCC, ANO1, VGCC, HCN channels and potassium channels , which can generate a large number of pacing current to form the slow wave and then propagated by the gap junction between the ICC networks and smooth muscle cells to make the peristalsis of gastrointestinal tract in autonomic rhythm .However, the mechanism of these ion channels in the pacemaker activity is still unclear , so we refer to make a review about the re-search progress on these pacemaker channels in this article to illuminate the mechanism of pacemaker activity in ICC .

7.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-494438

RESUMEN

Objective:To investigate the expression of protein arginine methyltransferase 5 (PRMT5)in the gastric cancer tissue,and to explore the relationship between the PRMT5 expression and the occurrence and the clinicopathologic characteristics of gastric cancer, and to find a new treatment target for gastric cancer.Methods:Forty-three cases of gastric cancer tissue and 15 cases of adjacent normal gastric tissue were used as gastric cancer group and control group,respectively.The immunohistochemical staining was used to detect the expression of PRMT5 in the specimens.Results:Compared with control group (13.3%),the expression rate of PRMT5 in gastric cancer group (72.1%)was significantly increased (P 0.05).Conclusion:High expression of PRMT5 may play an important role in the occurrence and development of gastric cancer.

8.
Journal of Clinical Hepatology ; (12): 2353-2355, 2016.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-778346

RESUMEN

ObjectiveTo investigate the clinical features of extrahepatic biliary adenoma and the role of endoscopic retrograde cholangiopancreatography (ERCP) in the diagnosis and treatment of extrahepatic biliary adenoma. MethodsA retrospective analysis was performed for the clinical manifestations, imaging findings, ERCP treatment, and follow-up data of 7 patients with extrahepatic biliary adenoma who were admitted to Department of Gastroenterology in The People′s Hospital of Northern Jiangsu from January 2010 to June 2016. Results Selective ERCP was performed for 7 patients after the exclusion of surgical contraindications. Intraoperative cholangiography showed interruption of different parts of the bile duct, and brush cytology under the guidance of guide wire and bile duct biopsy with ultrafine biopsy forceps were performed for all patients. The pathological examination showed bile duct adenoma. Among these patients, 6 were treated with ERCP and 1 was treated with Roux-en-Y choledochojejunostomy after ERCP. ConclusionAs a minimally invasive examination, ERCP helps to determine the cause of the disease and evaluate patients′ condition. When patients have surgical contraindications or are not willing to choose surgery, ERCP can be used as palliative therapy to relieve their clinical symptoms.

9.
Chinese Pharmacological Bulletin ; (12): 833-837,838, 2015.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-600809

RESUMEN

Aim To observe the effects of the total fla-vonoids of scutellaria barbataon ( TFSB ) on high-fat feeding ApoE gene deficiency mice in early atheroscle-rosis ( AS ) and its underlying mechanisms. Methods 40 ApoE-/ -male mice were divided into five groups:model group, SIM group and L-TFSB, M-TFSB, H-TFSB group, 5 C57BL/6J mice were selected as nor-mal control group. All mice in experimental group were fed with high-lipid diet for 4 weeks and all mice were killed after 8 weeks. H&E staining was used to observe morphology of aorta. Blood rheometer was used to ex-amine plasm viscosity and whole blood viscosity. Fully automatic biochemical analyser was used to detect the serum levels of TG, TC, LDL-C and HDL-C. The ex-pression levels of PLTP and VE in serum were meas-ured by ELISA. The expression levels of PLTP and FXR in liver were examined by Western blot. Results The model was established successfully. TFSB groups could improve the aorta AS morphology of model mice and significantly reduce the serum levels of TG, TC and LDL-C, while increase the level of HDL-C ( P hematocrit value, plasma viscosity and whole blood vis-cosity of AS model mice significantly and had statistical significance when compared with model group ( P <0. 01 ) . The expression levels of PLTP of serum were reduced significantly when compared with model group ( P <0. 01 ) . We also found that the expression of PLTP was in negative correlation with VE ( r = -0. 675,P<0. 01). M-TFSB and H-TFSB group could decrease the expressions of PLTP and FXR of liver when compared with model group ( P <0. 01 ) . Con-clusion TFSB may exert its anti-AS effect partly through inhibiting the levels of FXR and PLTP of ApoE-/ -mice, increasing the level of VE, regulating blood lipids, improving blood rheology and reducing the damage of AS in mice.

10.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-313058

RESUMEN

<p><b>OBJECTIVE</b>To investigate the correlation between the pathogeneses of diarrhea-pre- dominant irritable bowel syndrome (D-IBS) complicated functional dyspepsia (FD) patients of Gan-stagnation Pi-deficiency Syndrome (GSPDS) and symptoms, psychological states, and gastrointestinal hormones.</p><p><b>METHODS</b>A total of 111 patients with confirmed D-IBS complicated FD of GSPDS were recruited as the treated group by using Rome III standard and Chinese medical syndrome standard. And 30 healthy volunteers were recruited as the control group. The general condition, scoring for digestive symptoms, and the distribution of GSPDS subtype of all subjects were recorded by a questionnaire, and assessed by Symptom Checklist (SCL-90; a software for psychological test developed by Beijing Huicheng Adult Cor- poration). Meanwhile, plasma levels of 5-hydroxytryptamine (5-HT), somatostatin (SS), vasoactive intestinal peptide (VIP), endothelin (ET), interleukin 10 (IL-10), and interleukin 12 (IL-12) were measured in all subjects.</p><p><b>RESULTS</b>(1) The subtype of D-IBS complicated FD of GSPDS was dominant in Pi-qi deficiency type (51/111,45.9%),Pi yang deficiency type (34/111,30.6%), and GSPDS. There was no statistical difference in the scoring of digestive symptoms among the 3 subtypes (P >0.05). (2) Compared with the control group, the anxiety factor score and the total score significantly increased in all three subtypes of D-IBS complicated FD of GSPDS, and the depression score of Pi yang deficiency type and Gan-depression type also significantly increased (P <0.05, P <0.01); the depression score of Gan-depression type was significantly higher than that of the Pi-qi deficiency type (P <0.01). Plasma 5-HT levels were obviously lower in D-IBS complicated FD patients of GSPDS accompanied with anxiety or depression than in those with no obvious psychological abnormalities, and VIP and IL-10 levels were significantly lower than those in the control group (P <0.05). Plasma VIP levels were also obviously lower in D-IBS complicated FD patients of GSPDS accompanied with anxiety or depression than in those with no obvious psychological abnormalities (P <0.01), and SS levels were significantly lower than those in the control group (P <0.05). There was no statistical difference in plasma ET or IL-12 levels in each patient group, when compared with the control group (P >0.05). (3) Compared with the.control group, plasma 5-HT levels significantly increased, plasma VIP and IL-10 levels significantly decreased in ach subtype of D-IBS complicated FD patients of GSPDS (P <0.05, P <0.01), and no significant change of SS, ET, or IL-12 occurred (P >0.05). Besides, plasma 5-HT levels were significantly higher in Gan-depression type than in Pi yang deficiency type, VIP levels were lower in Gan-depression type than in Pi-qi deficiency type (all P <0.05).</p><p><b>CONCLUSIONS</b>Gan stagnation and Pi deficiency were dominant in D-IBS complicated FD patients of GSPDS. Psychological abnormalities, increased plasma 5-HT levels, and decreased plasma VIP levels were closely correlated with Gan stagnation subtype, which provided some reference for looking for objective indicators of Chinese medical syndromes in treating D-IBS complicated FD patients of GSPDS.</p>


Asunto(s)
Adulto , Humanos , Estudios de Casos y Controles , Diarrea , Dispepsia , Sangre , Psicología , Hormonas Gastrointestinales , Sangre , Síndrome del Colon Irritable , Sangre , Psicología , Pruebas Psicológicas , Qi , Serotonina , Encuestas y Cuestionarios , Deficiencia Yang
11.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-327852

RESUMEN

Wogonin is a kind of natural flavonoid compound. According to findings in the latest studies, wogonin shows a wide range of antitumor effects, with the characteristics of multi-pathway, multi-link and multi-target, such as promoting tumor cell apoptosis through ROS or Ca(2+)-mediated signal paths, enhancing tumor cytotoxicity by TNF-α and TRAIL, blocking tumor cell cycle, inhibiting tumor angiogenesis and resisting cancer synergistically with chemotherapeutic drugs. Moreover, Wogonin could enhance body immune function by enhancing immune cell infiltration, regulating the immune cell phenotype and promoting relevant cytokine secretion. In this paper, the authors summarized the advance in studies on wogonin's antitumor and immunomodulatory effects.


Asunto(s)
Animales , Humanos , Antineoplásicos , Usos Terapéuticos , Apoptosis , Medicamentos Herbarios Chinos , Usos Terapéuticos , Flavanonas , Usos Terapéuticos , Factores Inmunológicos , Usos Terapéuticos , Neoplasias , Quimioterapia , Alergia e Inmunología , Factor de Necrosis Tumoral alfa , Genética , Alergia e Inmunología
12.
The Journal of Practical Medicine ; (24): 1702-1704, 2014.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-453023

RESUMEN

Objective To investigate the role of tyrosine kinase Src in a murine C.albicans infection model. Methods Observed cell proliferation by alarmarblue assay at 2, 24 and 48 h after Src inhibitor PP2 treatment. Phagocytosis was determined by a fluorometric assay. Cytokine TNF-αand IL-10 production was detected by ELISA. Results The 0~33.3 μmol/L PP2 had no effect on cell proliferation after PP2 treatment for 2 h. When the PP2 treatment extended to 24 or 48 h, PP2 (11.1, 33.3μmol/L) showed significant inhibition on cell proliferation with 78%, 9%, and 54%,13%, respectively. At 48 h after 11.1μmol/L PP2 treatment, the internalization of C.albicans in macrophage is significantly inhibited, contributing to the inhibition of cell proliferation. However, the 11.1 and 33.3μmol/L PP2 significantly inhibited the cytokine TNF-αand IL-10 production during C.albicans infection (P<0.01). Conclusion Src kinase played an important role during C.albicans infection, especially for the cytokine TNF-αand IL-10 production.

13.
Chinese Journal of Digestion ; (12): 88-92, 2013.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-431406

RESUMEN

Objective To investigate the psychological status of diarrhea type irritable bowel syndrome (D-IBS) patients overlapped with functional dyspepsia (FD) and its relationship with the changes of brain-gut peptides and cytokines levels.Methods A total of 190 D-IBS FD overlapped patients and 30 healthy controls were selected and all of them completed the questionnaire.The adult psychological testing system was applied for the Symptom Checklist (SCL-90) assessment.Plasma levels of 5-hydroxytryptamine (5-HT),somatostatin (SS),vasoactive intestinal peptide (VIP),endothelin (ET),interleukin (IL)-10 and IL-12 were measured in 59 randomly selected patients.Single factor analysis of variance and LSD test were performed for statistical analysis.Results In D-IBS-FD overlapped patients,the plasma 5 HT levels of the D-IBS patients and the FD patients were (1906.83±676.88) μg/L and (1745.53±653.23) μg/L respectively,both of them were significant higher than those of control group [(1289.44±918.45) μg/L,LSD test,both P<0.05].However the levels of VIP and IL-10 were significant lower than those of control group (LSD test,both P<0.01).In D-IBS patients,the plasma level of SS was significantly lower than that of control group (LSD test,P=0.025); the level of ET was significantly higher than that of control group and FD patients (LSD test,both P<0.05).In D-IBS-FD overlapped patients,the scores of anxiety,depression and opponent were higher than those of control group (F=5.114,4.555 and 10.285,all P<0.05).The plasma VIP and SS levels of patients with anxiety or depression were lower than those of control group (LSD test,both P<0.05).The plasma VIP level was lower than that of patients without psychological disorders (LSD test,P=0.005).The plasma ET level of patients with disease course over five years was significantly higher than that of patients with disease course less than one year or between one and five years (LSD test,both P<0.05),and the IL-10 level was significantly lower than that of patients with disease course less than one year (LSD test,P=0.004).Conclusions There were sub-healthlated with disease course,psychological disorder,the increased plasma 5-HT level and the decreased IL-10 level.There was close correlation between the lower gastrointestinal symptoms and the decreased levels of VIP,SS and the increased level of ET.

14.
Acta Pharmaceutica Sinica ; (12): 934-940, 2012.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-276219

RESUMEN

The microbial transformation of buflomedil by Cunninghamella blakesleana AS 3.153 was studied, as well as a microbial model which can be used to mimic metabolism of buflomedil in mammal was established. Experiments were conducted to screen the capabilities of four strains of Cunninghamella species to transform buflomedil, in which C. blakesleana AS 3.153 was selected for a preparative biotransformation. Furthermore, the microbial model was established based on the transformation condition optimization. The parent drug and its metabolites produced by C. blakesleana AS 3.153 were detected by liquid chromatography-mass spectrometry method and three metabolites were identified while two of them were new found metabolites. Two major metabolites, para-O-desmethyl buflomedil and 12-C-oxidated buflomedil, were isolated by semi-preparative HPLC. Based on the comparison between different species, the microbial transformation of buflomedil by C. blakesleana AS 3.153 is more similar to the metabolism of buflomedil in human and Beagle dog than that in rat.


Asunto(s)
Adulto , Animales , Perros , Femenino , Humanos , Masculino , Ratas , Adulto Joven , Biotransformación , Cromatografía Líquida de Alta Presión , Cunninghamella , Metabolismo , Estructura Molecular , Pirrolidinas , Química , Farmacocinética , Ratas Wistar , Espectrometría de Masa por Ionización de Electrospray
15.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-419447

RESUMEN

Galanin is a peptide with wide-ranging effects,especially within the central,peripheral nervous system and endocrine system.Many tumors of neuroendocrine origin,and also an increasing number of non-neuroendocrine cancers,have been shown to express galanin and/or its receptors.Expression of galanin peptide has been detected in pheochromocytoma,squamous cell carcinoma,pituitary adenoma,gastrointestinal cancers and so on.Galanin peptide plays an important role in tumori-genesis and progression of many kinds of tumors.Therefore,studying the roles of galanin and its receptors are helpful for diagnosis and treatment of tumors.

16.
Acta Pharmaceutica Sinica ; (12): 934-40, 2012.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-431028

RESUMEN

The microbial transformation of buflomedil by Cunninghamella blakesleana AS 3.153 was studied, as well as a microbial model which can be used to mimic metabolism of buflomedil in mammal was established. Experiments were conducted to screen the capabilities of four strains of Cunninghamella species to transform buflomedil, in which C. blakesleana AS 3.153 was selected for a preparative biotransformation. Furthermore, the microbial model was established based on the transformation condition optimization. The parent drug and its metabolites produced by C. blakesleana AS 3.153 were detected by liquid chromatography-mass spectrometry method and three metabolites were identified while two of them were new found metabolites. Two major metabolites, para-O-desmethyl buflomedil and 12-C-oxidated buflomedil, were isolated by semi-preparative HPLC. Based on the comparison between different species, the microbial transformation of buflomedil by C. blakesleana AS 3.153 is more similar to the metabolism of buflomedil in human and Beagle dog than that in rat.

17.
Chinese Medical Journal ; (24): 172-176, 2011.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-321475

RESUMEN

<p><b>BACKGROUND</b>Both repaglinide and gliclazide are insulin secretagogues widely used in the treatment of type 2 diabetes. They stimulate insulin secretion through distinct mechanisms and may benefit patients from different aspects. The present study was to evaluate the effects of repaglinide or gliclazide on glycaemic control, insulin secretion, and lipid profiles in type 2 diabetes patients.</p><p><b>METHODS</b>A total of 47 newly diagnosed type 2 diabetes patients were randomized 1:1 to receive a 4-week treatment with repaglinide or gliclazide. The standard mixed meal tolerance test was performed before and after the treatment. Plasma glucose (PG), insulin concentration, and lipid profiles were measured. The area under insulin concentration curve (AUC(ins)) and the early-phase insulin secretion index (ΔI(30)/ΔG(30)) were calculated.</p><p><b>RESULTS</b>After the trial, fasting and postprandial PG and postprandial insulin improved significantly in both groups (P < 0.05). The maximum insulin concentration occurred earlier in the repaglinide group than that in the gliclazide group. AUC(ins) increased in both groups (P < 0.05), but no significant difference was found between groups. ΔI(30)/ΔG(30) increased in both groups (P < 0.05), especially in the repaglinide group (P < 0.05). Triglyceride and total cholesterol decreased significantly in the repaglinide group in some time points, while no significant change was observed in the gliclazide group.</p><p><b>CONCLUSIONS</b>Repaglinide and gliclazide had similar effects on glycaemic control and total insulin secretion, while repaglinide had more effects on improvements in β-cell function and lipid metabolism.</p>


Asunto(s)
Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Glucemia , Carbamatos , Usos Terapéuticos , Colesterol , Sangre , Diabetes Mellitus Tipo 2 , Sangre , Quimioterapia , Metabolismo , Ayuno , Sangre , Gliclazida , Usos Terapéuticos , Hipoglucemiantes , Usos Terapéuticos , Insulina , Secreciones Corporales , Piperidinas , Usos Terapéuticos , Periodo Posprandial , Resultado del Tratamiento , Triglicéridos , Sangre
18.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-422162

RESUMEN

Transient receptor potential (TRP) is a kind of novel Ca2+ permeant channel.It is later found that TRP channels are expressed broadly in many organisms,tissues and cell types.It is involved in the regulation of sensory conduction and cell signal transduction.Further studies are required to assess which TRPC6(a member of TRPC subfamily) is associated with the cytosolic Ca2+ levels,development and progression of cancer and tumor cell cycle.TRPC6 may be regarded as new targets for the treatment of cancer.

19.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-344523

RESUMEN

<p><b>OBJECTIVE</b>To discover new chemopreventive agents, a drug screening cell model based on reporter gene and antioxidative response element (ARE) has been established.</p><p><b>METHOD</b>Four repeas of ARE DNA binding conserved sequences were synthesized and cloned into a GFP expression vector. This construct was stably transfected into HepG2 cells in vitro. The cell model was tested with known chemopreventive agents and the effects of resveratrol, protocatechuic aldehyde, ursolic acid and oleanolic acid at different concentration (0, 12.5, 25, 50, 100, 200 micromol x L(-1)) were observed by determining reporter gene GFP activity.</p><p><b>RESULT</b>The induce level of GFP was regulated by ARE and the dose-dependence in a certain range was observed. The induce level of GFP by resveratrol was significantly increased.</p><p><b>CONCLUSION</b>The method can be used to screening of chemopreventive agents from Chinese traditional medicine by measurement of luminescent value of expressed GFP in wells of microtiter plate.</p>


Asunto(s)
Humanos , Antineoplásicos , Farmacología , Quimioprevención , Ensayos de Selección de Medicamentos Antitumorales , Métodos , Medicamentos Herbarios Chinos , Farmacología , Expresión Génica , Genes Reporteros , Proteínas Fluorescentes Verdes , Genética , Metabolismo , Células Hep G2 , Modelos Biológicos , Neoplasias , Quimioterapia
20.
Chinese Medical Journal ; (24): 395-400, 2004.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-346663

RESUMEN

<p><b>BACKGROUND</b>The activation of extracellular signal-regulated kinase1/2 (ERK1/2) has been shown to be important signaling pathway in the ischemic preconditioning (IPC) response. Recently, some studies suggest a key role for the mitochondrial ATP-sensitive potassium channel (mKATP) as both a trigger and an end effector of acute and delayed protection of IPC. Hence, this study was undertaken to elucidate the relationship between mKATP and ERK1/2 in the delayed protection mechanism of anoxic preconditioning (APC).</p><p><b>METHODS</b>An APC model was established using cultured neonatal rat cardiomyocytes. Pharmacological agents [diazoxide, 5-hydroxydecanoate (5-HD), 2-mercaptopropionylglycine (MPG), and PD98059] were used to modulate mKATP and ERK1/2 activation. Cellular injury was evaluated by measuring cellular superoxide dismutase (SOD) activity, cell viability, and lactate dehydrogenase (LDH) release. The generation of cellular reactive oxygen species (ROS) and the activation of ERK1/2 were determined at different time points starting from the beginning of preconditioning with anoxia or diazoxide (an mKATP opener).</p><p><b>RESULTS</b>Cell viability and SOD activity in the APC [(81.9 +/- 11.4)%, (13.6 +/- 3.7) U/L] and diazoxide [(79.2 +/- 12.4)%, (16.5 +/- 4.6) U/L] groups were significantly higher than in the anoxia/reoxygenation (A/R) [(42.2 +/- 7.3)%, (8.8 +/- 2.8) U/L] group (all P < 0.01). LDH activity in the APC group [(101.9 +/- 18.9) U/L] and diazoxide group [(97.5 +/- 17.7) U/L] was significantly lower than in the A/R group [(250.5 +/- 43.6) U/L] (all P < 0.01). Both APC and diazoxide simultaneously facilitated intracellular ROS generation and rapid ERK1/2 activation. But the effects of APC and diazoxide were remarkedly attenuated by 5-HP (an mKATP blocker) and by MPG (a free radical scavenger). In addition, the ERK1/2 inhibitor PD98059 also abolished the cellular protective effects induced by diazoxide.</p><p><b>CONCLUSION</b>mKATP may mediate ERK1/2 activation during anoxia preconditioning by generating ROS, which then triggers the delayed protection of APC in rat cardiomyocytes.</p>


Asunto(s)
Animales , Ratas , Animales Recién Nacidos , Células Cultivadas , Activación Enzimática , Precondicionamiento Isquémico , Proteínas Quinasas Activadas por Mitógenos , Metabolismo , Miocitos Cardíacos , Fisiología , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno , Metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA