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2.
Sci Rep ; 14(1): 11700, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778184

RESUMO

Jiarong Tibetan is a regional group with distinctive regional characteristics and possess precious traditional village resources. Studying the spatial distribution and influencing factors of traditional villages is of vital significance for the protection and renewal of villages and the revitalization of cultural heritage. Nevertheless, due to the fact that the Jiarong Tibetan inhabited area has not been clearly defined for a long time, there is a lack of holistic discussion on the distribution features and driving mechanisms of traditional villages in this region. In order to fill this research gap, the paper is the first to break away from the existing county administrative divisions to define the study area. Moreover, the analysis is carried out by using the nearest neighbor index, kernel density, GoeDa and Geodetector, etc. for traditional villages at national-level and provincial-level. The results show that the spatial distribution of the traditional villages of Jiarong Tibetan is characterized by typical aggregation, with the core intensive area in Danba County and the sub-core intensive area in the central and northern parts. The results of factor detection show that the spatial distribution pattern of the traditional villages is the consequence of the synergistic effect of multiple factors, and the interaction effect is significantly enhanced. The economic level and climatic conditions play a controlling role, and population, elevation, intangible cultural heritage and rivers also have notable effects. The findings of study can offer scientific guidance and suggestions for the inheritance and development of traditional villages in Jiarong Tibetan settlement area.

3.
Molecules ; 28(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36677795

RESUMO

The aim of this study was to improve the solubility, bioavailability, and stability of resveratrol (RES-SD) Solid Dispersion in Polygonum cuspidatum extract (PCE) by hot melt extrusion (HME). In addition, the role of the auxiliary substances in PCE was also studied. The solid dispersion of Polygonum cuspidatum extract was prepared by hot-melt extrusion. The optimum formula was selected by single factor design and orthogonal test. The optimum formula was barrel temperature 140 °C, screw rotation speed 40 rpm/min, and the ratio of Polygonum cuspidatum extract to HPMCAS was 1:2. The dissolution test showed that PCE-SD increased the dissolution of RES from 46.75 ± 0.47% to 130.06 ± 0.12%. The pharmacokinetics curve of rats showed that PCE-SD increased AUC0-t of RES from 111,471.22 ± 11.4% to 160,458.968 ± 15.7%, indicating an approximately 1.44-fold increase in absorption. In addition, the rotation speed of PCE-SD screw is less than that of RES-SD screw. The bioavailability of PCE-SD was slightly better than that of RES-SD. PCE-SD is more hygroscopic than RES-SD. PCE-SD increased the solubility and oral bioavailability of RES. The auxiliary substances in Polygonum cuspidatum extract have influence on its preparation technology, stability, and bioavailability.


Assuntos
Fallopia japonica , Tecnologia de Extrusão por Fusão a Quente , Ratos , Animais , Resveratrol , Disponibilidade Biológica , Solubilidade , Extratos Vegetais , Temperatura Alta , Composição de Medicamentos
4.
World J Gastrointest Endosc ; 15(12): 705-714, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38187912

RESUMO

BACKGROUND: Precleaning is a key step in endoscopic reprocessing. AIM: To develop an effective and economic endoscope cleaning method by using a disposable endoscope bedside precleaning kit. METHODS: Altogether, 228 used gastrointestinal endoscopes were selected from five high-volume endoscopy units and precleaned by a traditional precleaning bucket (group T) or a disposable endoscope bedside precleaning kit (group D). Each group was further subdivided based on the replacement frequency of the cleaning solution, which was replaced every time in subgroups T1 and D1 and every several times in subgroups Ts and Ds. The adenosine triphosphate (ATP) level and residual proteins were measured three times: Before and after precleaning and after manual cleaning. RESULTS: After precleaning, the precleaning kit significantly reduced the ATP levels (P = 0.034) and has a more stable ATP clearance rate than the traditional precleaning bucket. The precleaning kit also saved a quarter of the cost of enzymatic detergent used during the precleaning process. After manual cleaning, the ATP levels were also significantly lower in the precleaning kit group than in the traditional precleaning bucket group (P < 0.05). Meanwhile, the number of uses of the cleaning solution (up to four times) has no significant impact on the cleaning effect (P > 0.05). CONCLUSION: Considering its economic cost and cleaning effect, the use of a disposable endoscope bedside precleaning kit can be an optimal option in the precleaning stage with the cleaning solution being replaced several times in the manual cleaning stage.

5.
J Transl Med ; 20(1): 529, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376950

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a metabolic disorder with abnormal lipid metabolism. The present study was to identify regulatory genes related to lipid droplets (LDs) abnormal accumulation in NAFLD. METHODS: transcriptomic analysis and bioinformatics analysis (GEO database) were used to identify potential genes in abnormal lipid metabolism of NAFLD. A candidate gene MAP3K4 expression were detected by immunohistochemistry staining in NAFLD and controls. RNA interference and immunoblotting were used to verify the roles of MAP3K4 in the formation of hepatic LDs. RESULTS: A total of 134 candidate genes were screened, including 44 up-regulated genes and 90 down-regulated genes. 29 genes in the protein-protein interaction (PPI) were selected as hub genes, including MAP3K4. The expression levels of MAP3K4 were positively correlated with NAFLD activity score (r = 0.702, p = 0.002). Furthermore, we found a positive correlation of MAP3K4 expression with serum total cholesterol (r = 0.564, p = 0.023), uric acid levels (r = 0.520, p = 0.039), and body mass index (r = 0.574, p = 0.020). Downregulation of MAP3K4 decreased LDs accumulation in HepG2 cells and reduced the expression of CGI-58 and Plin-2 by imbibition of JNK and group IVA cytosolic phospholipase A2 (cPLA2) activation. CONCLUSION: The study revealed a number of regulatory genes related to hepatic lipid metabolism of NAFLD, and demonstrated that MAP3K4 played a pivotal role in the hepatic lipogenesis of NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Células Hep G2 , Metabolismo dos Lipídeos/genética , Lipogênese/genética , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo
6.
Front Endocrinol (Lausanne) ; 13: 895593, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35957832

RESUMO

Metabolic-associated fatty liver disease (MAFLD) affects approximately a quarter of the global population. Identification of the key genes and pathways involved in hepatic lipid metabolism is of the utmost importance for the diagnosis, treatment, and prevention of MAFLD. In this study, differentially expressed genes were identified through whole-genome transcriptional analysis of liver tissue from MAFLD patients and healthy controls, and a series of lipid metabolism-related molecules and pathways were obtained through pathway analysis. Subsequently, we focused on Iroquois homeobox protein 3 (IRX3), one of 13 transcription factors that were screened from the 331 differentially expressed genes. The transcription factor IRX3 was significantly decreased in the liver tissue of patients with MAFLD when compared with healthy controls. Pearson's correlation analysis showed that the expression levels of IRX3 in liver tissue were negatively correlated with serum total cholesterol, triglycerides, low-density lipoprotein cholesterol, and uric acid levels. The overexpression and interference of IRX3 induced the increased and decreased lipid droplet accumulation in vitro, respectively. Moreover, interference of IRX3 expression increased mitochondrial fragmentation and reduced the activity of the mitochondrial respiratory chain complex IV. In summary, the study demonstrated that IRX3 regulated hepatic lipid metabolism of MAFLD, and also revealed the effect of IRX3 on mitochondria might be an important mechanism by which IRX3 regulated hepatic lipid metabolism of MAFLD.


Assuntos
Proteínas de Homeodomínio , Metabolismo dos Lipídeos , Fígado , Hepatopatia Gordurosa não Alcoólica , Fatores de Transcrição , Colesterol/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
J Immunol Res ; 2022: 2156204, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35747689

RESUMO

Objective: The active ingredients extracted from natural plants have anti-GC actions and can slow down gastric carcinoma (GC) progression. To investigate the impact of Amarogentin (AG) on GC cell multiplication, apoptosis and migration and the possible mechanisms. Methods: qRT-PCR quantification of circKIF4A and miR-152-3p in GC tissues and normal counterparts as well as HGC-27 (human GC cell strain) and GES-1 (human gastric mucosal epithelial cell strain) was performed. HGC-27 cells were intervened by AG of various concentrations. si-NC, si-circKIF4A were further transfected into HGC-27 cells. Besides, pcDNA and pcDNA-circKIF4A were transfected into HGC-27 cells, after which 60 mmol/L AG was added for intervention. Cell multiplication, clone formation, as well as apoptosis and migration measurements were made by MTT, plate clone formation, flow cytometry and Transwell assays, respectively; Double luciferase reporter assay was performed for targeting relationship identification between circKIF4A and miR-152-3p; Western blots were carried out to measure Bax and Bcl-2 protein levels. Results: circKIF4A increased (P <0.05) and miR-152-3p decreased (P <0.05) in GC tissues and cell strains. Concentration-dependently, AG intervention contributed to enhanced cell multiplication inhibitory rate, apoptosis rate, miR-152-3p expression and Bax protein level (P <0.05), together with declined number of cell clones formed, migrating cells, circKIF4A expression and Bcl-2 protein level (P <0.05). After transfection of si-circKIF4A, cell multiplication inhibition rate, apoptosis rate and Bax protein level enhanced (P <0.05), while cell clones formed and migrating cells as well as Bcl-2 protein level reduced (P <0.05). miR-152-3p can be controlled by circKIF4A; pcDNA-circKIF4A transfection antagonized AG's effects on HGC-27 cell multiplication, clone formation, apoptosis and migration. Conclusion: AG can decrease GC multiplication, clone formation and migration and induce apoptosis via modulating circKIF4A/miR-152-3p expression.


Assuntos
Carcinoma , MicroRNAs , Neoplasias Gástricas , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Iridoides , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias Gástricas/patologia , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
8.
Front Cell Dev Biol ; 9: 741710, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869329

RESUMO

Metabolic associated fatty liver disease (MAFLD) is associated with obesity, type 2 diabetes mellitus, and other metabolic syndromes. Farnesoid X receptor (FXR, NR1H4) plays a prominent role in hepatic lipid metabolism. This study combined the expression of liver genes in FXR knockout (KO) mice and MAFLD patients to identify new pathogenic pathways for MAFLD based on genome-wide transcriptional profiling. In addition, the roles of new target genes in the MAFLD pathogenic pathway were also explored. Two groups of differentially expressed genes were obtained from FXR-KO mice and MAFLD patients by transcriptional analysis of liver tissue samples. The similarities and differences between the two groups of differentially expressed genes were analyzed to identify novel pathogenic pathways and target genes. After the integration analysis of differentially expressed genes, we identified 134 overlapping genes, many of which have been reported to play an important role in lipid metabolism. Our unique analysis method of comparing differential gene expression between FXR-KO mice and patients with MAFLD is useful to identify target genes and pathways that may be strongly implicated in the pathogenesis of MAFLD. The overlapping genes with high specificity were screened using the Gene Expression Omnibus (GEO) database. Through comparison and analysis with the GEO database, we determined that BHMT2 and PKLR could be highly correlated with MAFLD. Clinical data analysis and RNA interference testing in vitro confirmed that BHMT2 may a new regulator of lipid metabolism in MAFLD pathogenesis. These results may provide new ideas for understanding the pathogenesis of MAFLD and thus provide new targets for the treatment of MAFLD.

9.
Molecules ; 26(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34443551

RESUMO

Hot-melt extrusion (HME) has great advantages for the preparation of solid dispersion (SD), for instance, it does not require any organic solvents. Nevertheless, its application to high-melting-point and thermosensitive drugs has been rarely reported. In this study, thermally unstable curcumin (Cur) was used as a drug model. The HME process was systematically studied by adjusting the gradient temperature mode and residence time, with the content, crystallinity and dissolution of Cur as the investigated factors. The effects of barrel temperature, screw speed and cooling rate on HME were also examined. Solubility parameters and the Flory-Huggins method were used to evaluate the miscibility between Cur and carriers. Differential scanning calorimetry, X-ray diffraction, Fourier transform infrared spectroscopy, equilibrium solubility and in vitro and in vivo experiments were used to characterize and evaluate the results. An amorphous Cur SD was successfully obtained, increasing the solubility and release of Cur. In the optimal process, the mass ratio of Cur to Eudragit® E PO (EPO) was 1:4 and the barrel temperature was set at a gradient heating mode (130 °C-135 °C-140 °C-145 °C-150 °C-155 °C-160 °C) at 100 rpm. Related pharmacokinetic test results also showed the improved bioavailability of the drug in rats. In a pharmacodynamic analysis of Sprague-Dawley rats, the Cmax and the bioavailability of the Cur-EPO SD were 2.6 and 1.5 times higher than those of Cur, respectively. The preparation of the amorphous SD not only provided more solubility but also improved the bioavailability of Cur, which provides an effective way to improve the bioavailability of BCS II drugs.


Assuntos
Curcumina/química , Portadores de Fármacos/química , Temperatura Alta , Ácidos Polimetacrílicos/química , Disponibilidade Biológica , Curcumina/farmacocinética , Transição de Fase
10.
Molecules ; 26(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34443569

RESUMO

This study aimed to prepare a sustained-release solid dispersion of poorly water-soluble resveratrol (RES) with high melting point in a single hot melt extrusion step. A hydrophobic-hydrophilic polymeric blend (Eudragit RS and PEG6000) was used to control the release of RES. With the dispersive mixing and high shear forces of hot melt extrusion, the thermodynamic properties and dispersion of RES were changed to improve its solubility. The effects of the formulation were investigated through univariate analysis to optimize the preparation of the sustained-release solid dispersion. In vitro and in vivo studies were performed to evaluate the prepared RES/RS/PEG6000 sustained-release solid dispersion. The physical state of the solid dispersion was characterized using differential scanning calorimetry and X-ray diffraction. Surface properties of the dispersion were visualized using scanning electron microscopy, and the chemical interaction between RES and excipients was detected through Fourier-transform infrared spectroscopy. Results suggested that the optimized sustained-release solid dispersion was obtained when the mass ratio of RES-polymeric blend was 1:5, the ratio of PEG6000 was 35%, the barrel temperature was 170 °C, and the screw speed was 80 rpm. In vitro studies demonstrated that the solid dispersion showed a good sustained release effect. The cumulative release of RES reached 82.42% until 12 h and was fit by the Weibull model. In addition, the saturated solubility was 2.28 times higher than that of the bulk RES. In vitro studies demonstrated that the half-life increased from 3.78 to 7.09 h, and the bioavailability improved to 140.38%. The crystalline RES was transformed into the amorphous one, and RES was highly dispersed in the polymeric blend matrix.


Assuntos
Tecnologia de Extrusão por Fusão a Quente , Resveratrol/química , Resveratrol/farmacocinética , Disponibilidade Biológica , Preparações de Ação Retardada , Portadores de Fármacos/química , Temperatura Alta , Interações Hidrofóbicas e Hidrofílicas , Polietilenoglicóis/química , Solubilidade
11.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(6): 575-582, 2021 Jun 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34275925

RESUMO

OBJECTIVES: To compare the expression of the Wnt signaling-associated proteins (Wnt3, ß-catenin, MMP-7) in gastric cancer and precancerous lesions with positive and negative Helicobacter pylori (H.pylori, Hp) infection, and to further explore the mechanisms underlying the Wnt signaling pathway involving in the formation of gastric cancer and its relationship with Hp infection. METHODS: The complete paraffin samples with pathologically confirmed diagnosis, who came from the First Hospital of Changsha from January 2018 to April 2020, were collected. All samples were randomly divided into a gastric cancer group (n=57), a precancerous lesion group (n=84), and a chronic superficial gastritis group (n=25). Improved Giemsa staining was used to detect Hp infection, and according the results of Hp infection the above groups were divided into a Hp positive subgroup and a negative subgroup. The expressions of Wnt3, ß-catenin and MMP-7 were examined with immunohistochemistry. RESULTS: The Wnt3, ß-catenin, and MMP-7 were highly expressed in the gastric cancer group and the gastric precancerous lesion group. The Wnt3 and MMP-7 were highly expressed in cytoplasm, and ß-catenin showed a tendency of cell membrane transferring to cytoplasm and nucleus, which was characterized by "nuclear translocation". The positive rates of the Wnt3, ß-catenin, and MMP-7 expressions in the gastric cancer group were higher than those in the precancerous lesion group and the chronic superficial gastritis group (all P<0.05), which showed a gradually increasing trend with the deterioration of differentiation degree. In addition, the expressions of Wnt3, ß-catenin, and MMP-7 in the Hp positive subgroup in the gastric cancer group and the precancerous lesion group were higher than those in the Hp negative subgroup (all P<0.05). CONCLUSIONS: Aberrant activation of Wnt signaling pathway is involved in the occurrence and development of precancerous lesions and gastric cancer, and which is related with Hp infection. Meanwhile, the Wnt3, ß-catenin and MMP-7 may be used as molecular markers for early diagnosis of gastric cancer and indicators to judge the degree of differentiation and malignancy of gastric cancer.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Neoplasias Gástricas , Mucosa Gástrica , Humanos , Metaloproteinase 7 da Matriz/genética , Proteína Wnt3 , beta Catenina/genética
12.
J Pharm Sci ; 109(3): 1253-1260, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31794699

RESUMO

The purpose of this study was to optimize hot-melt extrusion (HME) preparation process and evaluate in vitro and in vivo for developing curcumin (CUR) sustained-release solid dispersion, to explore the possibility of HME for one-step preparation of insoluble drug sustained-release solid dispersion. The effect of 3 process parameters-barrel temperature, screw speed, and cooling rate-was systematically studied. Physical state of CUR sustained-release solid dispersion was characterized by differential scanning calorimetry, X-ray powder diffraction, and Fourier transform infrared spectroscopy. It was found that CUR-Eudragit RS/RL system exhibited a good miscibility. Curcumin in the solid dispersion existed in an amorphous state and had molecular interactions with carriers. Stability studies showed no apparent difference of physical state of solid dispersion after 6 months. The mechanism of the CUR release in sustained-release solid dispersion was a diffusion and dissolution coexisting action. Pharmacokinetics study showed the relative bioavailability of the CUR in sustained-release solid dispersion to CUR was 223.44%. The CUR sustained-release solid dispersion have been successfully prepared by HME, significantly extending the half-life, ensuring a stable and effective blood concentration, and improving the bioavailability of CUR. In conclusion, HME can be used to prepared sustained-release solid dispersion of a poorly water-soluble drug as a promising method.


Assuntos
Curcumina , Varredura Diferencial de Calorimetria , Preparações de Ação Retardada , Composição de Medicamentos , Tecnologia de Extrusão por Fusão a Quente , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
13.
J Pharm Sci ; 109(3): 1242-1252, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31809744

RESUMO

The purpose of this study was to optimize the formulation for developing curcumin sustained-release solid dispersion to increase the solubility of curcumin, delay drug release by hot-melt extrusion, and to explore the possibility of hot-melt extrusion for one-step preparation of insoluble drug sustained-release solid dispersion. The miscibility of curcumin and Eudragit RSPO and Eudragit RLPO were assessed by solubility parameter and melting point depression. Orthogonal test was used to optimize the formulation, based on the results of single-factor experiment, and the final optimal formulation: the ratio of the sustained-release carrier material RS/RL was 1:3, the ratio of drug and carrier was 1:6, and the porogen was used in an amount of 40% of the sustained-release carrier material. The curcumin solid dispersion of the best formulation had been prepared and had a significant sustained-release effect compared to the curcumin and the physical mixture.


Assuntos
Curcumina , Tecnologia de Extrusão por Fusão a Quente , Preparações de Ação Retardada , Portadores de Fármacos , Composição de Medicamentos , Liberação Controlada de Fármacos , Temperatura Alta , Solubilidade
14.
RSC Adv ; 9(39): 22263-22273, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-35519487

RESUMO

The aim of the study was to develop an amorphous solid dispersion of a poorly water-soluble drug with high melting point by ball milling and hot melt extrusion as a co-processing method. Solid dispersion systems were prepared by ball milling-hot melt extrusion and then compared with those prepared with hot melt extrusion. The effects of three process parameters in the co-processing method, namely, barrel temperature, screw speed, and cooling rate, were systematically studied. The physical state of prepared solid dispersion was characterized by differential scanning calorimetry, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, phase solubility, and dissolution study. The Resveratrol-Eudragit® EPO system exhibited good miscibility and significant dissolution enhancement. Resveratrol in the amorphous solid dispersion existed in an amorphous state and had molecular interactions with Eudragit® EPO. Stability studies showed no apparent difference in the physical state of the solid dispersion after 6 months. In conclusion, combining ball milling with hot melt extrusion is a promising method for preparing the amorphous solid dispersion of a poorly water-soluble drug with high melting point.

15.
ACS Omega ; 3(11): 16175-16183, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31458254

RESUMO

In this study, hydroxyl-terminated polybutadiene-poly(epoxide ionic liquid)-poly(urethane urea) (HTPB-PEIL-PU) membranes, HTPB-PEIL1-PU and HTPB-PEIL2-PU, were prepared by the reaction of functionalized PEIL, poly(1-methylimidazole-3-methyl-ethyloxy)hexafluorophosphate or poly(1-methylimidazole-3-methyl-ethyloxy)bistrifluoromethanesulfonimidate, respectively, with HTPB using 4,4'-diphenylmethane diisocyanate (MDI) as the chain extender. The HTPB-PEIL-PU and HTPB membranes were investigated for the selective recovery of n-butanol from aqueous solutions by pervaporation. PEIL was confirmed to be successfully embedded in the PU membranes by 1H NMR, Fourier transform infrared, and differential scanning calorimetry measurements. According to our mechanical measurements, the HTPB-PEIL-PU membranes retain the mechanical properties of the original PU membrane. PEIL was shown to enhance the diffusion rate of n-butanol significantly based on swelling behavior tests. The pervaporation flux through the HTPB-PEIL1-PU membrane increased with increasing feed temperature and feed concentration. In contrast, the separation factor of the HTPB-PEIL1-PU membrane increased with increasing feed temperature but decreased with increasing feed concentration. In addition, the HTPB-PEIL2-PU membrane exhibited an optimal separation factor of up to 29.2 at a feed concentration of 3% and a feed temperature of 70 °C, which is superior to that (22.7) through pure HTPB membranes. Furthermore, the HTPB-PEIL1-PU and HTPB-PEIL2-PU membranes show better long-term stability than other supported ionic liquid membranes.

16.
J Biomed Mater Res B Appl Biomater ; 105(7): 1737-1746, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27177987

RESUMO

Polyethylene glycol (PEG) and heparin (Hep) were grafted onto polysulfone (PSF) membrane by plasma-induced surface modification to prepare PSF-PEG-Hep membranes used for artificial lung. The effects of plasma treatment parameters, including power, gas type, gas flow rate, and treatment time, were investigated, and different PEG chains were bonded covalently onto the surface in the postplasma grafting process. Membrane surfaces were characterized by water contact angle, PEG grafting degree, attenuated total reflectance-Fourier transform infrared spectroscopy, ultraviolet-visible spectrophotometry, X-ray photoelectron spectroscopy, critical water permeability pressure, and scanning electron microscopy. Protein adsorption, platelet adhesion, and coagulation tests showed significant improvement in the hemocompatibility of PSF-PEG-Hep membranes compared to pristine PSF membrane. Gas exchange tests through PSF-PEG6000-Hep membrane showed that when the flow rate of porcine blood reached 5.0 L/min, the permeation fluxes of O2 and CO2 reached 192.6 and 166.9 mL/min, respectively, which were close to the gas exchange capacity of a commercial membrane oxygenator. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1737-1746, 2017.


Assuntos
Plaquetas/metabolismo , Oxigenação por Membrana Extracorpórea , Heparina/química , Teste de Materiais , Membranas Artificiais , Gases em Plasma/química , Adesividade Plaquetária , Polietilenoglicóis/química , Polímeros/química , Sulfonas/química , Humanos
17.
Artif Organs ; 40(11): E219-E229, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28374499

RESUMO

Polysulfone (PSF) was grafted chemically with polyethylene glycol (PEG) of different molecular weights (400, 2000, 10 000, and 20 000) and heparin to prepare PSF-PEG-Hep membranes (labeled as PSF-PEG400-Hep, PSF-PEG2000-Hep, PSF-PEG10 000-Hep, and PSF-PEG20 000-Hep). These membranes were synthesized via the following steps: (i) PSF chloromethylation; (ii) PEGylation; and (iii) heparin immobilization process. Water contact angle, critical water permeation pressure, ATR-FTIR, 1 H NMR, UV-visible spectrophotometry, and X-ray photoelectron spectroscopy were conducted to prove grafting success and to fix the optimal reaction parameters during chemical modification processes. To further evaluate the application potential of the PSF-PEG-Hep membrane in a membrane oxygenator, we conducted pure CO2 and O2 gas permeation tests and measured the gas exchange rates of CO2 and O2 through a membrane oxygenator using fresh porcine blood. Meanwhile, the hemocompatibility of the membrane was analyzed and compared by protein adsorption, platelet adhesion, and blood coagulation tests. Results of pure gas permeation experiments indicated that the excellent gas transmission properties through PSF membrane were preserved after modification. Blood oxygenation experiments through the PSF-PEG10 000-Hep membrane showed that when the flow rate of porcine blood was 1.5 L/min, CO2 and O2 exchange rates reached 102 and 110 mL/min, respectively, which could basically satisfy the gas exchange potential of commercial membrane oxygenators. Besides, the PSF-PEG-Hep membrane has demonstrated more prominent blood compatibility than PSF.


Assuntos
Materiais Biocompatíveis/química , Heparina/química , Oxigenadores de Membrana , Polietilenoglicóis/química , Polímeros/química , Sulfonas/química , Adsorção , Testes de Coagulação Sanguínea , Teste de Materiais , Membranas Artificiais , Adesividade Plaquetária , Propriedades de Superfície
18.
Biomed Mater ; 10(6): 065022, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26658212

RESUMO

In this study, polyethylene glycol acrylate (PEGA) was introduced onto the surface of polysulphone (PSF) membrane to prepare PSF-PEGA membranes through low-temperature plasma technology for haemocompatibility improvement of artificial lungs. The effects of plasma power, PEGA solution concentration and dipcoating temperature on surface modification were systematically investigated. Results of Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy and PEGA grafting degree confirmed that PEGA was successfully grafted onto the PSF membranes. Contact angle values showed that the hydrophilicity of the PSF-PEGA membrane surface increased by 21.5%. The results of the protein adsorption, platelet adhesion and coagulation tests further showed the excellent haemocompatibility of the modified membrane. Gas exchange tests also revealed that at a porcine blood flow rate of 5 l min(-1), O2 and CO2 exchange rates through the PSF-PEGA membrane were 198.6 and 170.9 ml min(-1), respectively; approximately this is the gas exchange capacity of commercial respiratory assistance devices.


Assuntos
Resinas Acrílicas/química , Órgãos Artificiais , Oxigenação por Membrana Extracorpórea/instrumentação , Pulmão/fisiologia , Membranas Artificiais , Polietilenoglicóis/química , Troca Gasosa Pulmonar/fisiologia , Animais , Materiais Biocompatíveis/síntese química , Velocidade do Fluxo Sanguíneo/fisiologia , Desenho de Equipamento , Análise de Falha de Equipamento , Oxigenação por Membrana Extracorpórea/métodos , Humanos , Teste de Materiais , Gases em Plasma/química , Propriedades de Superfície , Suínos
19.
Zhongguo Zhong Yao Za Zhi ; 38(19): 3277-81, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24422391

RESUMO

The membrane enrichment process of traditional Chinese medicine volatile oil is environmental friendly and practical, with a good application prospect. In this article, oil-bearing solutions of eight traditional Chinese medicines, namely Caryophylli Flos, Schizonepetae Herba, Eupatorii Herb, Acori Talarinowii Rhizoma, Magnoliae Flos, Chrysanthemum indicum, Cyperi Rhizoma and Citri Reticulatae Pericarpium Viride, were taken as the experimental system. Under unified conditions (membrane: PVDF-14W, temperature: 40 degreeC, pressure: 0. 1 MPa, membrane surface speed: 150 r min- 1), trans-membrane was conducted for above eight oil-bearing solutions to explore the effect of their oil-bearing solution environment on system flux and oil recovery rate. The results showed that systems with smaller pH had a lower flux, without significant effect on oil recovery rate. Greater differences between the surface tension of solutions and that of pure water contributed to a lower oil recovery rate. The conductivity had no notable effect on membrane enrichment process. Systems with high turbidity had a lower flux, without remarkable effect on oil recovery rat. Heavy oils showed lower flux than light ones, but with a slightly higher oil recovery rat. Systems with higher viscosity had a lower flux than those with lower viscosity. Except for Magnoliae Flos volatile oil, all of the remaining volatile oils showed a much higher oil recovery rat than systems with high viscosity. The above results could provide data support and theoretical basis for the industrialization of membrane enrichment volatile oil technology.


Assuntos
Medicamentos de Ervas Chinesas/química , Medicina Tradicional Chinesa/métodos , Óleos de Plantas/química , Syzygium/química , Concentração de Íons de Hidrogênio , Temperatura
20.
Zhongguo Zhong Yao Za Zhi ; 38(20): 3461-6, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24490554

RESUMO

Membrane enrichment process of Chinese medicine volatile oil is green, practical and has a good application prospects. Schizonepetae Herba et al. six chinese medicine oily water were filtrated with polyvinylidene fluoride (PVDF) membrane with MWCO 70 000, at 40 degrees C, 0.1 MPa and 150 r x min(-1), common laws of physicochemical property of six oily water and fingerprint similarity between original and preserved oil were studied during membrane enrichment. Results were as follows: pH was gradually reduced to the minimum; conductivity firstly became larger, then smaller until 0; viscosity gradually increased to a maximum; surface tension gradually decreased to a minimum; turbidity firstly gradually increased, then reduced to a minimum; density gradually decreased to a minimum, but the change trend was opposite for Acori Tatarinowii Rhizoma with heavy oil; salinity was 0. In the end, pH reached a maximum and density reached a maximum (contrary for Acori Tatarinowii Rhizoma) and the other physicochemical property values reached a minimum for the last permeate. Fingerprint similarity between original and enriched volatile oil was above 90%. The above results provided data support and theoretical basis for the industrialization of membrane enrichment volatile oil technology.


Assuntos
Medicamentos de Ervas Chinesas/química , Óleos Voláteis/química , Plantas Medicinais/química , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/isolamento & purificação , Óleos Voláteis/isolamento & purificação
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