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Objective: To compare the clinical efficacy, prognostic factors, and survival impact of endoscopic submucosal dissection (ESD) versus endoscopic submucosal resection (ESR) in patients with colorectal neuroendocrine tumors (NETs). Methods: This retrospective study analyzed 118 patients with colorectal NETs treated from January 2012 to December 2020. Patients were divided into the ESD group (n=59) and the ESR group (n=59) based on the surgical treatment method. We assessed the surgical efficacy, long-term survival, and factors influencing tumor recurrence using logistic regression analysis with clear criteria for group division. Results: En bloc resection, complete histological resection rates, and postoperative complications did not significantly differ between groups (P > .05). In the 33 patients with recurrence, those with tumor diameter < 10 mm, tumor grade G1, and negative resection margins were significantly fewer (P < .05). Logistic regression identified tumor diameter, grade, and resection margin status as significant predictors of recurrence (P < .05). There was no significant difference in distant metastasis, survival rates, and mortality between the groups (P > .05). Conclusions: ESD and ESR offer high clinical efficacy in treating colorectal NETs without significantly impacting prognosis or long-term survival. ESD, however, may be more suited for larger tumors due to its precise tissue removal capability. Future research should explore the long-term outcomes over 3 and 5 years to further validate these findings.
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BACKGROUND The aim of this study was to compare the expression levels of mRNA of the B cell-specific Moloney murine leukemia virus integration site 1 (BMI-1) and the WW domain-containing oxidoreductase (WWOX) genes and their protein products in tissues from patients with liver cancer with normal liver tissues from patients without liver cancer. MATERIAL AND METHODS The liver cancer group (N=56) included patients with available tissue samples of histologically confirmed liver cancer. The control group (N=24) included histologically confirmed normal liver tissue samples. Immunofluorescence staining and Western blot were used to detect and compare protein expression of Bmi-1 and WWOX in liver tissues in the liver cancer group and the control group. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect and compare mRNA expression of BMI-1 and WWOX in liver tissues in the liver cancer group and the control group. Expression levels of the protein and mRNA levels and the clinicopathological features including patient prognosis in liver cancer were evaluated statistically using analysis of variance (ANOVA). RESULTS There were significant differences in the expression levels of protein and mRNA of BMI-1 and WWOX between the liver cancer group and the control group. BMI-1 mRNA and protein expression were significantly increased, and WWOX mRNA and protein expression were significantly reduced in liver cancer tissue, compared with normal liver tissue (p<0.05). CONCLUSIONS In liver cancer tissue compared with normal liver, the expression of BMI-1 and WWOX mRNA and their protein products were upregulated and down-regulated, respectively.
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Neoplasias Hepáticas/genética , Complexo Repressor Polycomb 1/genética , Proteínas Supressoras de Tumor/genética , Oxidorredutase com Domínios WW/genética , Adulto , Idoso , Carcinoma Hepatocelular/genética , China , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Fígado/citologia , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Vírus da Leucemia Murina de Moloney , Oxirredutases , Complexo Repressor Polycomb 1/metabolismo , Prognóstico , RNA Mensageiro , Proteínas Supressoras de Tumor/metabolismo , Oxidorredutase com Domínios WW/metabolismo , Domínios WWRESUMO
The effect of whey protein isolate (WPI)- galacto-oligosaccharides (GOS)/fructo-oligosaccharides (FOS) conjugates on RAW264.7 cells, and further the effect of WPI-GOS conjugates on CTX-induced immunosuppressed mice were investigated. Compared to WPI-FOS conjugates, WPI-GOS conjugates exhibited deeper glycation extent, more pronounced structural unfolding and helix-destabilizing, and obviously improved functional indicators of RAW264.7 macrophages. In addition, WPI-GOS conjugates also repaired immune organ and intestinal barrier and increased IL-1ß and IFN-γ levels in immunosuppressed mice. The alteration of gut microbiota induced by WPI-GOS conjugates changed the serum metabolites, causing the activation of NFκB pathway, which strengthens the immune system. The activation of NFκB pathway maybe associated with the mTOR signal pathway and ABC transporters. However, the precise mechanisms by which NFκB pathway interacts with mTOR signal pathway and ABC transporters to modulate the immune response need for further research.
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We prepared the ß-lactoglobulin (BLG)-ferulic acid (FA)-glucose (Glu) conjugates by alkaline method and Maillard reaction to assess the allergenicity. FA and Glu can form a ternary covalent conjugate with BLG, as evidenced by the shortening of SEC retention time, upward migration of SDS-PAGE protein bands, considerable decrease in free amino and sulfhydryl content, and changes in multistructure. BLG-Glu-FA conjugates weakly bound to immunoglobulin E in allergic sera was weak, reduced interleukin 4 and tumor necrosis factor α levels in RBL-2H3 cells and histamin and interleukin 6 secretion levels in KU812 cells, and inhibited the nuclear factor-κB signaling pathway. In vivo experiments showed that the conjugates regulated T-cell homeostasis in mouse splenic and mesenteric lymphocytes and attenuated splenic and duodenal immune injury. Therefore, the conjugates of BLG with FA combined with Glu altered the epitope structure and exhibited low allergenicity.
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A novel strategy combining ferulic acid and glucose was proposed to reduce ß-lactoglobulin (BLG) allergenicity and investigate whether the reduction in allergenicity was associated with gut microbiome and serum metabolism. As a result, the multistructure of BLG changed, and the modified BLG decreased significantly the contents of IgE, IgG, IgG1, and mMCP-1 in serum, improved the diversity and structural composition of gut microbiota, and increased the content of short-chain fatty acids (SCFAs) in allergic mice. Meanwhile, allergic mice induced by BLG affected arachidonic acid, tryptophan, and other metabolic pathways in serum, the modified BLG inhibited the production of metabolites in arachidonic acid metabolism pathway and significantly increased tryptophan metabolites, and this contribution helps in reducing BLG allergenicity. Overall, reduced allergenicity of BLG after ferulic acid was combined with glucose modification by regulating gut microbiota, the metabolic pathways of arachidonic acid and tryptophan. The results may offer new thoughts alleviating the allergy risk of allergenic proteins.
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Alérgenos , Ácidos Cumáricos , Microbioma Gastrointestinal , Glucose , Lactoglobulinas , Ácidos Cumáricos/metabolismo , Ácidos Cumáricos/química , Animais , Lactoglobulinas/imunologia , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Camundongos , Humanos , Alérgenos/imunologia , Alérgenos/química , Alérgenos/metabolismo , Glucose/metabolismo , Feminino , Bactérias/imunologia , Bactérias/metabolismo , Bactérias/classificação , Bactérias/genética , Camundongos Endogâmicos BALB C , Imunoglobulina E/imunologia , Imunoglobulina E/sangue , Ácidos Graxos Voláteis/metabolismo , Bovinos , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Hipersensibilidade a Leite/imunologiaRESUMO
The present study aims to investigate the effects of ultrasound on the non-covalent interaction of ß-lactoglobulin (ß-LG) and luteolin (LUT) and to investigate the relationship between allergenicity and human intestinal microbiota. After treatment, the conformational structures of ß-LG were changed, which reflected by the decrease in α-helix content, intrinsic fluorescence intensity and surface hydrophobicity, whereas the ß-sheet content increased. Molecular docking studies revealed the non-covalent interaction of ß-LG and LUT by hydrogen bond, van der Walls bond and hydrophobic bond. ß-LG-LUT complex treated by ultrasound has a lower IgG/IgE binding ability and inhibits the allergic reaction of KU812 cells, depending on the changes in the conformational epitopes of ß-LG. Meanwhile, the ß-LG-LUT complex affected the composition of human intestinal microbiota, such as the relative abundance of Bifidobacterium and Prevotella. Therefore, ultrasound improved the non-covalent interaction of ß-LG with LUT, and the reduction in allergenicity of ß-LG depends on conformational epitopes and human intestinal microbiota changes.
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The effects of phosphorylation on the allergenicity of bovine α-lactalbumin (BLA) and digestive products were studied in vitro digestion. Two components with different molecular weight and conformation were obtained from natural and phosphorylated BLA. In vivo and in vitro assessment of allergenicity showed that phosphorylation prior to digestion significantly decreased the IgE/IgG binding capacity and allergic response in KU812 cells, and reduced the levels of IgG, IgE, IL-4 and histamine, with an increase in IFN-γ levels in mouse serum, depending on the changes in BLA structures, producing numerous small peptides. There were four phosphorylated sites (S22, T29, S47 and S70) in the high molecular weight components of phosphorylated BLA after digestion. These phosphorylated sites could mask the linear epitopes of digestive products, resulting in reduced allergic activity. Phosphorylation prior to digestion of dairy products can reduce the risk of anaphylaxis in patients with milk allergy to some extent.
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Alérgenos , Lactalbumina , Animais , Bovinos , Digestão , Imunoglobulina E , Camundongos , FosforilaçãoRESUMO
The present study aims to investigate the structure of covalent conjugates of bovine ß-lactoglobulin (BLG) and flavonoids (luteolin, myricetin, and hyperoside), and their effect on the allergenicity and human intestinal microbiota. Covalent modification of amino acids in BLG by flavonoids was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and o-phthaldialdehyde assay. The secondary and conformational structures of BLG were changed by the covalent modification, which were determined by the circular dichroism, Fourier transform infrared spectroscopy, fluorescence spectroscopy, and UV spectroscopy. The enzyme-linked immunosorbent assay (ELISA) and cell experiments indicated that BLG covalent conjugates could reduce IgE/IgG binding capacities and suppress the allergy reactivity of RBL-2H3 cells, suggesting that the covalent modification modulated the balance of T cells. Meanwhile, covalent modification of BLG with these flavonoids can alter the diversity of human intestinal microbiota and the community abundance at phylum, family, and genus levels. The results revealed that covalent modification of BLG with flavonoids alters human intestinal microbiota, might result in the reduction of allergenicity, which could provide information for confirming the relationship between food allergy and the intestinal microbial ecosystem.
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Microbioma Gastrointestinal , Lactoglobulinas , Alérgenos , Animais , Bovinos , Ecossistema , Flavonoides , HumanosRESUMO
Bovine α-lactalbumin (α-Lac) allergy is a common health problem. This study assesses the allergenic reactivity and the structural properties of α-Lac after protein modification (glycation, phosphorylation and acetylation) by ELISA, cells experiment and high-resolution mass spectrometry. Three modified methods significantly reduced the IgE/IgG-binding capacity, and the release of histamine and interleukin-6, and changed the conformational structure of α-Lac. α-Lac was glycated at K13, K16, K94, K98, and K108, phosphorylated at Y18, S22, Y103, and S112, and acetylated at K13, T33, S34, T38, S47, K62, S69, S70, K108, and K114, respectively, leading to masking the linear epitopes of α-Lac. Therefore, the decrease of allergenic reactivity of α-Lac induced by glycation, phosphorylation and acetylation depends upon not only the shielding effect of their modified sites, but also the change of conformational structure. This study confirmed that protein modification was a promising method for decreasing the allergenic reactivity of allergic proteins.
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Alérgenos/imunologia , Lactalbumina/imunologia , Acetilação , Animais , Bovinos , Ensaio de Imunoadsorção Enzimática , Epitopos/metabolismo , Glicosilação , Imunoglobulina E/metabolismo , Espectrometria de Massas , Fosforilação , Processamento de Proteína Pós-TraducionalRESUMO
Bovine α-lactalbumin (α-La)/ß-lactoglobulin (ß-Lg) was pretreated through ultrasonic treatment and subsequently binding with oleic acid (OA) by heat treatment. And, the antitumor activity, IgE/IgG-binding ability, and structural modifications were investigated. After α-La/ß-Lg were treated by ultrasonic prior to binding with OA, the treated α-La/ß-Lg showed high antitumor activity and IgE/IgG-binding ability, and significantly affected the structural modifications, which reflected by the reduction in α-helix content, the increase of molecular weight, intrinsic fluorescence intensity, and surface hydrophobicity. Molecular docking studies indicated that OA bound to α-La/ß-Lg by hydrogen bonds and hydrophobic interaction. Therefore, ultrasonic prior to binding with OA could improve antitumor activity and IgE/IgG-binding ability of α-La/ß-Lg as a result of structural modifications. And, ultrasonic prior to binding with fatty acid processing of milk products alone may increase the antitumor activity, this change may enhance the risk of an allergenic reaction in milk allergy patients to some extent. PRACTICAL APPLICATIONS: Fatty acids, natural ligands associated with the bovine milk proteins, and milk protein-fatty acid complex has a variety of functional applications in the food industry. This study revealed that antitumor activity, IgE/IgG-binding ability, and structural modifications of α-La/ß-Lg induced by ultrasonic prior to binding with oleic acid. It will be beneficial to understand the mechanism of the functional changes of protein. Ultrasonic prior to binding with oleic acid will be more likely to develop a practical technology to improve the functional characteristics of milk protein and design the optimal nutritional performance of milk food.
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Lactalbumina , Lactoglobulinas , Animais , Bovinos , Humanos , Imunoglobulina E , Imunoglobulina G , Simulação de Acoplamento Molecular , Ácido OleicoRESUMO
Increasing evidence has revealed that long noncoding RNAs (lncRNAs) emerge as pivotal regulators in diverse cancers, including hepatocellular carcinoma (HCC). This study was conducted to investigate the role of lncRNA WWOX antisense RNA 1 (WWOX-AS1) in HCC progression. Our present study illustrated that WWOX-AS1 was lowly expressed in HCC tissues and cell lines. High WWOX-AS1 expression was further confirmed to predict a favorable prognosis in HCC patients. Through functional assays, we observed that upregulated WWOX-AS1 was correlated with decreased cell proliferation, migration, epithelial to mesenchymal transition (EMT) process and increased cell apoptosis, suggesting that WWOX-AS1 exerted anti-carcinogenic role in the development of HCC. Moreover, WWOX, the nearby gene of WWOX-AS1, was found at a low level in HCC tissues and cell lines. Furthermore, there was a positive relationship between WWOX-AS1 and WWOX. Additionally, WWOX overexpression hampered cell proliferation, migration, EMT process and induced cell apoptosis in HCC. Mechanically, WWOX-AS1 was identified as a cytoplasmic RNA in HCC cells and sponged miR-20b-5p to regulate WWOX expression. Rescue assays further indicated that WWOX knockdown counteracted WWOX-AS1 overexpression-mediated suppressive function on HCC progression. Collectively, WWOX-AS1/miR-20b-5p/WWOX axis suppresses HCC tumorigenesis, hinting a potential molecular mechanism for the therapy of HCC patients.
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Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Oxidorredutase com Domínios WW/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , RNA Antissenso/genética , RNA Antissenso/metabolismo , Proteínas Supressoras de Tumor/genética , Regulação para Cima , Oxidorredutase com Domínios WW/genéticaRESUMO
OBJECTIVE: To investigate expression profiles of survivin and endoglin in patients with hepatic carcinoma. MATERIALS AND METHODS: Cancerous tissues (hepatic carcinoma group) of 48 patients with hepatic carcinoma and adjacent noncancerous hepatic tissues (control group) were used as objects of study. Histopathological staining [hematoxylin & eosin (H&E) staining] was used to study the pathological differences in hepatic tissues between hepatic carcinoma group and control group. Moreover, survivin and endoglin protein expressions in hepatic tissues in hepatic carcinoma group and control group were detected via western blotting. Finally, Statistical Product and Service Solutions 17.0 statistical software was used to analyze the differences in survivin and endoglin expressions in hepatic tissues between hepatic carcinoma group and control group. RESULTS: H&E staining showed that histopathological features in hepatic carcinoma group were significantly different from those in control group. Compared with those in control group, the cell structure in hepatic carcinoma group was damaged, karyopyknosis was obvious, and the hepatic injury was serious. Reverse transcription-polymerase chain reaction showed that survivin and endoglin mRNA expression levels in hepatic carcinoma group were significantly increased compared with those in control group. Besides, immunofluorescence method and western blotting revealed the low expressions of survivin and endoglin proteins in tissues in control group, which were obviously lower than those in hepatic tissues in hepatic carcinoma group. Results of analyses of variance showed that the expressions of survivin and endoglin in normal hepatic tissues and cancerous tissues had statistically significant differences (p < 0.01). Furthermore, expressions of survivin and endoglin were significantly associated with histological grade, tumor size, and tumor, node, metastasis (TNM) stage. CONCLUSION: Elevated expressions of survivin and endoglin are associated with histological grade, tumor size, and TNM stage in patients with hepatic carcinoma, indicating that survivin and endoglin might be involved in the pathogenesis of hepatic carcinoma and therapeutic targeting them might be a novel approach for the treatment of hepatic carcinoma.
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Carcinoma Hepatocelular/metabolismo , Endoglina/biossíntese , Neoplasias Hepáticas/metabolismo , Survivina/biossíntese , Adulto , Idoso , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Endoglina/genética , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Survivina/genéticaRESUMO
PURPOSE: As a conserved cellular stress response, autophagy has recently been demonstrated to be involved in the pathogenesis of several human cancers. Beclin-1 is an important autophagy gene that is abnormally expressed in a variety of human cancers. In this study, we investigated the expression of Beclin-1 in Hepatocellular Carcinoma (HCC). METHODS: A total of 83 patients with primary HCC were enrolled in this study. The expression of Beclin-1, PCNA, NET-1, Bcl-2, and Bax was measured in tissue microarray, including 83 cases of HCC and 46 adjacent non-tumor liver tissues. The association of the expression of Beclin-1 with clinicopathological features as well as PCNA, NET-1, Bcl-2, and Bax were analyzed. RESULTS: The positive rate of Beclin-1 in HCC tissues was significantly lower than that in adjacent tissues (x2 = 4.013, p=0.012). Beclin-1 expression in HCC tissues was negatively correlated with the expression of PCNA, NET-1, and anti-apoptotic protein Bcl-2, but positively correlated with pro-apoptotic protein Bax expression. Meanwhile, Beclin-1 expression was negatively correlated with HCC Edmondson grading (p=0.0058). Furthermore, Beclin-1 expression was significantly lower in HCC patients with liver cirrhosis (p=0.029) or vascular invasion (p=0.011) than those in HCC patients without cirrhosis or vascular invasion. CONCLUSION: Decreased expression of Beclin-1 was observed in HCC tissues and negatively correlated with HCC Edmondson grading, suggesting that Beclin-1 might be a valuable prognostic indicator for HCC.
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Proteína Beclina-1/genética , Carcinoma Hepatocelular/genética , Proliferação de Células/genética , Neoplasias Hepáticas/genética , Apoptose/genética , Autofagia/genética , Carcinoma Hepatocelular/patologia , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Hepáticas/patologia , Masculino , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Análise Serial de Tecidos , Proteína X Associada a bcl-2/genéticaRESUMO
As a new type of functional material, magnetic thermosensitive polymeric microspheres offer high potential application in various fields, particularly in bioengineering and biomedical fields. In this review, the development of synthesis and application of magnetic thermosensitive polymeric microspheres was summarized, and the research trends were also discussed.
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Materiais Biocompatíveis/química , Magnetismo , Microesferas , Polímeros/química , Tamanho da Partícula , TemperaturaRESUMO
Environmental stimuli-sensitive biodegradable drug delivery systems are drawing more and more attentions because of their advantages such as smart properties, high efficiency and easy-to-handle properties. On the basis of a large quantity of references on this topic, a review has been made on the developments of the thermosensitive and pH-sensitive intelligent polymeric systems for drug delivery.
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Materiais Biocompatíveis/química , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Materiais Biocompatíveis/farmacologia , Biodegradação Ambiental , Quitosana/química , Excipientes/química , Humanos , Polietilenoglicóis/química , Poliglactina 910/químicaRESUMO
A glucose-sensitive microcapsule with a porous membrane and with linear-grafted polyacrylic acid (PAAC) chains and covalently bound glucose oxidase (GOD) enzymes in the membrane pores acting as functional gates was successfully prepared. Polyamide microcapsules with a porous membrane were prepared by interfacial polymerization, PAAC chains were grafted into the pores of the microcapsule membrane by plasma-graft pore-filling polymerization, and GOD enzymes were immobilized onto the PAAC-grafted microcapsules by a carbodiimide method. The release rates of model drug solutes from the fabricated microcapsules were significantly sensitive to the existence of glucose in the environmental solution. In solution, the release rate of either sodium chloride or VB(12) molecules from the microcapsules was low but increased dramatically in the presence of 0.2mol/L glucose. The prepared PAAC-grafted and GOD-immobilized microcapsules showed a reversible glucose-sensitive release characteristic. The proposed microcapsules provide a new mode for injection-type self-regulated drug delivery systems having the capability of adapting the release rate of drugs such as insulin in response to changes in glucose concentration, which is highly attractive for diabetes therapy.
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Resinas Acrílicas/química , Cápsulas/química , Glucose Oxidase/química , Membranas Artificiais , Composição de Medicamentos/métodos , Enzimas Imobilizadas/química , Tamanho da Partícula , Porosidade , Cloreto de Sódio/química , Propriedades de Superfície , Fatores de Tempo , Vitamina B 12/químicaRESUMO
Experimental investigations on the Shirasu-porous-glass (SPG)-membrane emulsification processes for preparing monodisperse core-shell microcapsules with porous membranes were carried out systematically. The results showed that, to get monodisperse oil-in-water (O/W) emulsions by SPG membrane emulsification, it was more important to choose an anionic surfactant than to consider hydrophile-lipophile balance (HLB) matching. Increasing the viscosity of either the disperse phase or the continuous phase or decreasing the solubility of the disperse phase in the continuous phase could improve both the monodispersity and the stability of emulsions. With increasing monomer concentration inside the disperse phase, the monodispersity of emulsions became slightly worse and the mean diameter of emulsions gradually became smaller. Monodisperse monomer-containing emulsions were obtained when the SPG membrane pore size was larger than 1.0 micro m, and from these emulsions satisfactory monodisperse core-shell microcapsules with a porous membrane were prepared. On the other hand, when the SPG membrane pore size was smaller than 1.0 mciro m, no monodisperse emulsions were obtained because of the formation and chokage of solid monomer crystals in the pores or at the end of the pores of the SPG membrane. This was due to the remarkable solvation and diffusion of the solvent in water. With increasing the emulsification time the average emulsion diameter generally decreased, and the monodispersity of the emulsions gradually became worse.
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AIM: To study the antagonistic effect of myricetin on platelet activing factor (PAF). METHODS: The specific binding of [3H] PAF to rabbit platelet receptor was investigated using radio ligand binding assay (RLBA). Platelet adhesion induced by PAF was measured with spectrophotometry. The elevation of inner free calcium concentration in rabbit polymorphonuclear leukocytes (PMNs) induced by PAF was assayed by Fura-2 fluorescent technique. RESULTS: The specific binding inhibition potency of Myr was found to be concentration-dependent. The IC50 of Myr in [3H] PAF 1, 2 and 4 nmol.L-1 were 34.8, 85.7 and 118.6 mumol.L-1, respectively. The PAF induced reactions of rabbit platelet adhesion and PMNs inner free calcium concentration increase were inhibited by Myr in a dose-dependent manner. The IC50 of Myr to inhibit platelet adhesion was 13.1 mumol.L-1. CONCLUSION: The specific receptor binding of PAF can be antagonized by myricetin.
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Cálcio/metabolismo , Flavonoides/farmacologia , Neutrófilos/metabolismo , Fator de Ativação de Plaquetas/antagonistas & inibidores , Adesividade Plaquetária/efeitos dos fármacos , Animais , Masculino , Fator de Ativação de Plaquetas/metabolismo , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Glicoproteínas da Membrana de Plaquetas/metabolismo , Coelhos , Receptores Acoplados a Proteínas G/metabolismoRESUMO
OBJECTIVE: To explore the inhibitory effect and mechanism of rutin against platelet activating factor (PAF) induced platelet aggregation, 5-HT release and intra-platelet free calcium concentration. METHODS: The rate of washed rabbit platelet (WRP) aggregation was measured by turbidimetry and O-phthaldialdehyde (OPT) fluoro-spectrophotometry (FSPM) was used to determine 5-HT content. The intraplatelet free calcium concentration was measured with Fura-2/AM FSPM assay. RESULTS: Rutin in vitro was concentration-dependently inhibiting PAF (9.55 x 10(-9) mol/L) induced WRP aggregation, the IC50 of 5-HT release was 0.73, 1.13 mmol/L respectively and the intraplatelet free calcium concentration elevation evoked by PAF (4.78 x 10(-10) mol/L) were inhibited by 68.3, 136, 274, 545 mumol/L of rutin dose-dependently. CONCLUSION: Rutin could inhibit PAF induced platelet aggregation, 5-HT release and the increase of intraplatelet free calcium.
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Fator de Ativação de Plaquetas/antagonistas & inibidores , Inibidores da Agregação Plaquetária/farmacologia , Rutina/farmacologia , Animais , Transporte Biológico Ativo , Plaquetas/metabolismo , Cálcio/metabolismo , Masculino , Ativação Plaquetária/efeitos dos fármacos , Coelhos , Serotonina/metabolismoRESUMO
OBJECTIVE: To observe the platelet activating factor (PAF) antagonistic effect of kaempferol. METHOD: The specific binding of [3H] PAF to rabbit platelet receptor was investigatedwith radio ligand binding assay (RLBA). Platelet adhesion induced by PAF was measured with spectrophotometry. The elevation of inner free calcium concentration in rabbit polymorphonuclear leukocytes (PMNs) induced by PAF was determined with Fura-2 fluorescent technique. RESULT: The 1, 2 or 4 nmol x L(-1) [3H]PAF specific binding to rabbit platelet receptor was inhibited by Kae dosage dependently and the IC50 were 30.8, 74.6 and 92.0 micro mol x L(-1), respectively. The PAF induced reactions of rabbit platelet adhesion and PMNs inner free calcium concentration elevation were inhibited by Kae in a dose-dependent manner. The IC50 of Kae to inhibit platelet adhesion was 65 micromol x L(-1). CONCLUSION: Kae is effective in inhibiting the action of PAF and it is a new PAF receptor antagonist.