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1.
Nanotechnology ; 34(19)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36745907

RESUMO

Self-powered wearable sensing systems have attracted great attention for their application in continuous health monitoring, which can reveal real-time physiological information on the body. Here, an innovative self-powered sound-driven humidity sensor for wearable intelligent dehydration monitoring system has been proposed. The sensor is primarily comprised of PTFE membrane, ZnO nanoarrays and Ti thin film. The piezoelectric/triboelectric effect of ZnO nanoarrays/PTFE membrane is coupled with the humidity sensing process. Sound wave can drive PTFE membrane to vibrate, and the contact and separation between PTFE and ZnO can generate electrical signals through piezoelectric/triboelectric effect. At the same time, the surface of the nanostructures can absorb the water molecules, which will influence the electrical output of the device. The device can convert sound energy into electrical output without any external electricity power supply, and the outputting voltage decreases with increasing relative humidity, acting as the sensing signal. The sensor has been integrated with data processing unit and wireless transmission module to form a self-powered wearable intelligent dehydration monitoring system, which can actively monitor the humidity of exhaled breath and transmit the information to the mobile phone. The results can open a possible new direction for the development of sound-driven gas sensors and will further expand the scope for self-powered nanosystems.


Assuntos
Dispositivos Eletrônicos Vestíveis , Óxido de Zinco , Humanos , Umidade , Desidratação , Politetrafluoretileno
2.
Drug Dev Ind Pharm ; 49(2): 217-231, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36994666

RESUMO

OBJECTIVE: To prepare porous core-shell composite particles (PCPs) in order to improve the flowability and compactibility of powder materials for direct compaction (DC), as well as the dissolution of tablets. SIGNIFICANCE: The results obtained are meaningful to boosting the development and further research of PCPs on DC. Methods: In this study, hydroxypropyl methylcellulose (HPMC E3) and polyvinylpyrrolidone (PVP K30) were selected as shell materials, the Xiao Er Xi Shi formulation powder (XEXS) was used as the core materials, ammonium bicarbonate (NH4HCO3), and sodium bicarbonate (NaHCO3) were employed as pore-forming agent. Using co-spray drying method to prepare composite particles (CPs). Then, the physical properties and comparison between different CPs were characterized comprehensively. Finally, the different CPs were directly compacted as tablets to explore the effect on the dissolution behavior of DC tablets, respectively. RESULTS: (i) The XEXS PCPs were prepared successfully by co-spray drying, and the yield of PCPs is almost 80%; (ii) The TS values of PCP-X-P-Na, PCP-X-P-NH4, PCP-X-H-Na and PCP-X-P-Na were 5.70, 7.56, 3.98, and 6.88 times higher than that of raw material (X); (iii) The disintegration time of PCPs tablets decreased 10-25% when compared with CPs tablets; (iv) The values of Carr's index (CI), Hausner ratio (HR), Caking strength (CS), and Cohesion index (CoI) of PCP-X-H-NH4 were 19.16%, 19.29%, 40.14%, and 6.39% lower than that of X, respectively. CONCLUSIONS: The PCPs prepared by co-spray drying did improve the flowability and compactibility of powder, as well as the dissolution of tablets.


Assuntos
Povidona , Pós , Porosidade , Composição de Medicamentos/métodos , Comprimidos , Solubilidade
3.
Artigo em Inglês | MEDLINE | ID: mdl-35491826

RESUMO

Most studies on microplastics (MPs) focused on gut, liver, and brain, and MPs toxicity was size-dependent, but less has been reported on gill. Here, zebrafish were exposed to three sizes of MPs (45-53 µm, 90-106 µm, and 250-300 µm). Next, comparative transcriptome analysis and determination of physiological indices were performed in zebrafish gills to elucidate the size-associated toxicity of MPs to fish gills. Compared with the control, 60, 344, and 802 differentially expressed genes (DEGs) were identified after exposure to 45-53 µm, 90-106 µm, and 250-300 µm MPs for 5 days, respectively. More DEGs in treatment with bigger MPs suggested that bigger MPs might induce more changes in zebrafish gills than smaller ones. These DEGs were significantly enriched in the FoxO signaling, cellular senescence, circadian rhythm and p53 signaling pathways. Besides, 90-106 µm and 250-300 µm MPs treatments inhibited the cell cycle and prevented the apoptosis. The GSH content significantly increased after MPs exposure, suggesting the induction of oxidative stress. AChE and Na+/K+-ATPase activities were significantly lowered in all MPs treatments than in the control, suggesting the inhibition of neurotransmission and ion regulation. These changes might negatively influence the normal functioning of gills, such as osmoregulation, ion regulation, and respiration.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Brânquias/metabolismo , Microplásticos/toxicidade , Plásticos , Transcriptoma , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo
4.
Ecotoxicology ; 30(10): 1997-2010, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34529203

RESUMO

Microplastics (MPs) are common environmental contaminants that present a growing health concern due to their increasing presence in aquatic and human systems. However, the mechanisms behind MP effects on organisms are unclear. In this study, zebrafish (Danio rerio) were used as an in vivo model to investigate the potential risks and molecular mechanisms of the toxic effects of polyethylene MPs (45-53 µm). In the zebrafish intestine, 6, 5, and 186 genes showed differential expression after MP treatment for 1, 5, and 10 days, respectively. In the gills, 318, 92, and 484 genes showed differential expression after MP treatment for 1, 5, and 10 days, respectively. In both the intestine and the gills, Gene Ontology (GO) annotation showed that the main enriched terms were biological regulation, cellular process, metabolic process, cellular anatomical entity, and binding. KEGG enrichment analysis on DEGs revealed that the dominant pathways were carbohydrate metabolism and lipid metabolism, which were strongly influenced by MPs in the intestine. The dominant pathways in the gills were immune and lipid metabolism. The respiratory rate of gills, the activity of SOD and GSH in the intestine significantly increased after exposure to MPs compared with the control (p < 0.05), while the activity of SOD did not change in the gills. GSH activity was only significantly increased after MP exposure for 5 days. Also, the MDA content was not changed in the intestine but was significantly decreased in the gills after MP exposure. The activity of AChE significantly decreased only after MPs exposure for 5 days. Overall, these results indicated that MPs pollution significantly induced oxidative stress and neurotoxicity, increased respiratory rate, disturbed energy metabolism and stimulated immune function in fish, displaying an environmental risk of MPs to aquatic ecosystems.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Ecossistema , Brânquias , Intestinos/química , Plásticos/toxicidade , Polietileno/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
5.
Int J Biol Macromol ; 270(Pt 1): 132088, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38723821

RESUMO

Chitosan, as a natural biomass material, is green, recyclable, sustainable and well biocompatible. The molecular chain is rich in active groups such as amino and hydroxyl groups, and its preparation of fluorescent probes has the advantages of biocompatibility and efficient detection performance. In this study, a bis(benzaldehyde) (BHD) fluorescent functional molecule was designed. Then a series of fluorescent chitosan-based hydrogel films (CSBHD) were prepared using chitosan as raw material and BHD as cross-linking agent. As a fluorescent probe for metal ions, CSBHD was able to efficiently detect Fe2+ with a linear correlation of fluorescence intensity in the range of 0-160 µM, and the limit of detection (LOD) was 0.55 µM. Moreover, it has excellent adsorption performance for Fe2+ ions, with a maximum adsorption capacity of 223.5 g/mg at 500 mg/L Fe2+ concentration. Finally, we characterised the structure and microscopic morphology of CSBHD films and found that CSBHD as a hydrogel film has a high cross-linking density, good water resistance, excellent thermal stability, strong resistance to swelling, and excellent stability in cycling tests. Hence, it has great potential for application in adsorption and detection of Fe2+ ions. It also provides a good strategy for the application of chitosan based fluorescent probe materials in environmental monitoring and heavy metal ion adsorption.


Assuntos
Benzaldeídos , Quitosana , Corantes Fluorescentes , Hidrogéis , Ferro , Quitosana/química , Adsorção , Hidrogéis/química , Ferro/química , Benzaldeídos/química , Corantes Fluorescentes/química , Reagentes de Ligações Cruzadas/química , Limite de Detecção , Membranas Artificiais , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
6.
Nano Lett ; 12(10): 5281-6, 2012 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-22947073

RESUMO

This paper describes a facile method for synthesis of Au-AgCdSe hybrid nanorods with controlled morphologies and spatial distributions. The synthesis involved deposition of Ag tips at the ends of Au nanorod seeds, followed by selenization of the Ag tips and overgrowth of CdSe on these sites. By simply manipulating the pH value of the system, the AgCdSe could selectively grow at one end, at both the ends or on the side surface of a Au nanorod, generating a mike-like, dumbbell-like, or toothbrush-like hybrid nanorod, respectively. These three types of Au-AgCdSe hybrid nanorods displayed distinct localized surface plasmon resonance and photoluminescence properties, demonstrating an effective pathway for maneuvering the optical properties of nanocrystals.

7.
Int J Biol Macromol ; 253(Pt 4): 127082, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37769762

RESUMO

The design and development of a rapid and quantitative method for the detection of heavy metal ions is of great importance for environmental protection. We have prepared a 1,8-Naphthalimide modified cellulose composite fluorescent hydrogel (CENAEA/PAA) with a stereo double network structure. Characterized by excellent hydrogel functional structure and fluorescence detection performance, it can efficiently and selectively identify and detect Cr(VI) with linear quenching in the range of 0-400 µmol/L and detection limit of 0.58 µmol/L for Cr(VI). The results show that the CENAEA/PAA can effectively adsorb Cr(VI) with a maximum adsorption capacity of 189.04 mg/g. Finally, the morphological characteristics, chemical structure, fluorescence properties and adsorption behavior of CENAEA/PAA were analyzed and fitted well with the pseudo-second-order model and Freundlich model. Thus, the present work provides a green and sustainable approach for the synthesis of a functional material that can be used for the detection and adsorption of heavy metal ions.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Naftalimidas , Corantes Fluorescentes , Hidrogéis , Cromo/química , Íons , Celulose/química , Adsorção , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de Hidrogênio
8.
Int J Biol Macromol ; 242(Pt 2): 124915, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37211080

RESUMO

Chitosan is a kind of natural polysaccharide biomass with the second highest content in nature after cellulose, which has good biological properties such as biocompatibility, biodegradability, hemostasis, mucosal adsorption, non-toxicity, and antibacterial properties. Therefore, hydrogels prepared from chitosan have the advantages of good hydrophilicity, unique three-dimensional network structure, and good biocompatibility, so they have received extensive attention and research in environmental testing, adsorption, medical materials, and catalytic supports. Compared with traditional polymer hydrogels, biomass chitosan-based hydrogels have advantages such as low toxicity, excellent biocompatibility, outstanding processability, and low cost. This paper reviews the preparation of various chitosan-based hydrogels using chitosan as raw material and their applications in the fields of medical materials, environmental detection, catalytic carriers, and adsorption. Some views and prospects are put forward for the future research and development of chitosan-based hydrogels, and it is believed that chitosan-based hydrogels will be able to obtain more valuable applications.


Assuntos
Quitosana , Quitosana/química , Materiais Biocompatíveis/química , Hidrogéis/química , Polissacarídeos/química , Celulose
9.
Colloids Surf B Biointerfaces ; 225: 113279, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36989815

RESUMO

Osteochondral defect repair is one of the challenging problems in orthopedics. In this study, a multilayer polycaprolactone (PCL) based fibrous membrane for osteochondral defect repair was biomimetically fabricated by combining self-induced crystallization, biomimetic mineralization and layer-by-layer electrospinning techniques. The multilayer functional bionic fibrous membrane consisted of cartilage repair layer, intermediate transition repair layer and subchondral bone repair layer. Glucosamine hydrochloride (GAH) encapsulated in core-shell structured PCL fibrous membrane (MGPCL) was suitable for cartilage repair. Shish-kebab (SK) structured PCL fibrous membrane with calcium phosphate coating (MSKPCL) was designed for subchondral bone repair. SK structured MGPCL fibrous membrane (SKMGPCL) was used as intermediate transition repair. The tensile modulus of MG/SKMG/MSKPCL fibrous membrane was 34.24 ± 2.39 MPa which met the requirements of cartilage and subchondral bone repair scaffolds, and in vitro culture results showed that MG/SKMG/MSKPCL fibrous membrane had good biological activity and osteogenic ability. These results showed that MG/SKMG/MSKPCL fibrous membrane provides a promising material basis for osteochondral integrated repair scaffold.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Alicerces Teciduais/química , Engenharia Tecidual/métodos , Biônica , Poliésteres/química
10.
Front Immunol ; 13: 1091786, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36618361

RESUMO

Purpose: HBsAg clearance represents clinical cure for patients with hepatitis B, but remains difficult to obtain for most HBV-infected patients. Recent studies have shown that inactive HBsAg carriers treated with pegylated interferon can achieve higher clinical cure rates, which may imply that the lower the baseline HBsAg quantification, the higher HBsAg clearance rate. Therefore, this study further investigated the HBsAg clearance rate in inactive HBsAg carriers with low level of HBsAg (<200 IU/ml) treated with pegylated interferon. Methods: This is a prospective cohort study. Inactive HBsAg carriers with HBsAg<200 IU/ml were divided into treatment and control groups. Pegylated interferon was administered to the patients in therapeutic group for 96 weeks. The patients in control group underwent 96 weeks of observation without any anti-viral treatment. All patients were tested for HBsAg, anti-HBs, HBV DNA, liver function, blood count, thyroid function, thyroid antibodies and autoantibodies at baseline, week 12, 24, 36, 48, 60, 72, 84 and 96. Controlled attenuation parameter (CAP) and liver stiffness measure (LSM) were evaluated at baseline and week 96. Patients were classified into no steatosis, mild steatosis, moderate steatosis and severe steatosis according to the value of CAP. Results: A total of 174 inactive HBsAg carriers with HBsAg<200IU/ml were enrolled, including 84 in the treatment group and 90 in the control group. In the treatment group, HBsAg clearance rate was 30.77% (24/78) at week 48, and increased to 57.69% (45/78) at week 96. HBsAg clearance occurred in 2 patients with a clearance rate of 2.27% (2/88) in control group, The HBsAg clearance rate of the treatment group was significantly higher than that of the control group (P<0.001). HBsAg clearance was significantly higher in patients with moderate steatosis than in those without steatosis (74.07% vs. 48.15%, p=0.008) at week 96. Conclusion: High HBsAg clearance rate could be obtained for inactive HBsAg carriers with HBsAg< 200 IU/ml treated with peginterferons. Inactive HBsAg carriers with moderate hepatic steatosis are more sensitive for the treatment.


Assuntos
Fígado Gorduroso , Hepatite B Crônica , Humanos , Antígenos de Superfície da Hepatite B , Interferons/uso terapêutico , Estudos Prospectivos , DNA Viral , Fígado Gorduroso/induzido quimicamente , Polietilenoglicóis/uso terapêutico
11.
Front Immunol ; 13: 864354, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35529845

RESUMO

Purpose: Our recent study showed a high rate of HBsAg clearance in inactive HBsAg carriers (IHCs) treated with pegylated IFN (PEG-IFN). To better understand the immune-mediated component of HBsAg clearance, this study investigated the role of serum immunoglobulin G (IgG) and its subclasses in predicting HBsAg clearance in IHCs with PEG-IFN therapy. Methods: In this study, IHCs received PEG-IFN for 96 weeks. Subjects who achieved clearance of HBsAg were considered responders (R group), and those in whom HBsAg was not cleared were considered non-responders (NR group). The HBsAg, ALT, and serum lgG subtypes (lgG1, IgG2, IgG3, lgG4) were tested at baseline, and at 12 and 24 weeks of treatment. To evaluate the factors in predicting HBsAg clearance, univariate and multivariate logistic regression analyses were performed. The receiver operator characteristic curves and the area under the receiver operator characteristic curve (AUROC) were used to evaluate prognostic values. Results: Our results showed that 39 cases obtained HBsAg clearance (group R), while 21 cases did not (group NR). There was no significant difference in age, ALT, and AST levels between the two groups. The serum levels of IgG1, lgG2, lgG3 and lgG4 at baseline, and at 12 and 24 weeks were significantly lower in IHC with HBsAg clearance than in the NR group. Univariate logistic regression analysis showed that serum IgG1, IgG2, IgG3, and IgG4 levels at baseline, and at 12, and 24 weeks were all strong predictors of HBsAg clearance. In all indicators, lgG2 had the highest AUROC at baseline and lgG3 the highest AUROC at week 12. A multifactor logistic analysis was performed with y=33.933-0.001*BaselinelgG1-0.002*BaselinelgG2. The area under the curve was 0.941 with 100% sensitivity and 76.19% specificity. Conclusion: Together, our findings suggest that serum IgG has a higher predictive value compared to the convention predictors of HBsAg and ALT for HBsAg clearance and thus may be a better clinical predictor of HBsAg clearance in IHCs.


Assuntos
Antígenos de Superfície da Hepatite B , Interferon-alfa , Antígenos de Superfície , Antivirais/uso terapêutico , Vírus da Hepatite B , Humanos , Imunoglobulina G/uso terapêutico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico
12.
ACS Appl Bio Mater ; 4(8): 6167-6174, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35006871

RESUMO

The repair of bone defects is one of the great challenges facing modern orthopedics clinics. Bone tissue engineering scaffold with a nanofibrous structure similar to the original microstructure of a bone is beneficial for bone tissue regeneration. Here, a core-shell nanofibrous membrane (MS), MS containing glucosamine (MS-GLU), MS with a shish-kebab (SK) structure (SKMS), and MS-GLU with a SK structure (SKMS-GLU) were prepared by micro-sol electrospinning technology and a self-induced crystallization method. The diameter of MS nanofibers was 50-900 nm. Contact angle experiments showed that the hydrophilicity of SKMS was moderate, and its contact angle was as low as 72°. SK and GLU have a synergistic effect on cell growth. GLU in the core of MS was demonstrated to obviously promote MC3T3-E1 cell proliferation. At the same time, the SK structure grown on MS-GLU nanofibers mimicked natural collagen fibers, which facilitated MC3T3-E1 cell adhesion and differentiation. This study showed that a biomimetic SKMS-GLU nanofibrous membrane was a promising tissue engineering scaffold for bone defect repair.


Assuntos
Nanofibras , Colágeno , Nanofibras/química , Poliésteres/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química
13.
Chemosphere ; 270: 128613, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33131733

RESUMO

Most previous researches focused on the toxicity of polystyrene microplastics (MPs) to marine organisms, but less on polyethylene MPs and freshwater zooplanktons. The present study aims to elucidate the toxicity of polyethylene (PE) MPs (diameter = 10-22 µm) to the typical freshwater rotifer Brachionus calyciflorus. Firstly, fluorescent microscope observation showed that rotifers could ingest PE MPs and accumulate them in their digestive tracts. Life-table experiments revealed that exposure to 0.5 × 103, 2.5 × 103, and 1.25 × 104 particles/mL PE MPs significantly reduced net reproductive rate and intrinsic rate of pollution increase of rotifers under algal densities (Scenedesmus obliquus) of 0.1 × 106, and 0.5 × 106 cells/mL, but no significant effects were observed under 2.5 × 106 cells/mL algal density. These results showed that PE MPs suppressed the reproduction of rotifer and this negative effect could be alleviated by increasing food supply. The swimming linear speed of rotifers significantly decreased with increasing MP concentrations. The activities of superoxide dismutase and Na+-K+-ATPase significantly decreased in treatments with high concentration of PE MPs under 0.1 × 106 cells/mL algal density, but did not change significantly in MP treatments under 0.5 × 106 and 2.5 × 106 cells/mL, compared to the control. Glutathione peroxidase activity significantly increased in treatments with 1.25 × 104 particles/mL and 2.5 × 103 particles/mL under 0.1 × 106 and 0.5 × 106 cells/mL algal density, respectively, but did not change significantly in all MP treatments under 2.5 × 106 cells/mL. Exposure to PE MPs might lower the gathering capacity of algae, induce oxidative stress, trigger cell membrane damages and disturb energy metabolism in rotifers, which can explain the PE MPs toxicity to rotifer reproduction.


Assuntos
Rotíferos , Poluentes Químicos da Água , Animais , Água Doce , Microplásticos , Plásticos , Polietileno/toxicidade , Poluentes Químicos da Água/toxicidade
14.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(3): 229-235, 2019 Jun 01.
Artigo em Zh | MEDLINE | ID: mdl-31218853

RESUMO

Tooth preparation is the primary and core operation technique for dental esthetic restoration treatment, due to its effect of providing restoration space, bonding interfaces and marginal lines for dental rehabilitation after tooth tissue reduction. The concept of microscopic minimal invasive dentistry put forward the issue of conducting high-quality tooth preparation, conserve tooth-structure, protect vital pulp and periodontal tissue simultaneously. This study reviewed the concepts, physiology background, design and minimal invasive microscopic tooth preparation, and in the meantime, individualized strategies and the two core elements of tooth preparation (quantity and shape) are listed.


Assuntos
Porcelana Dentária , Estética Dentária , Preparo do Dente , Restauração Dentária Permanente
15.
Di Yi Jun Yi Da Xue Xue Bao ; 25(4): 422-3, 2005 Apr.
Artigo em Zh | MEDLINE | ID: mdl-15837644

RESUMO

OBJECTIVE: To evaluate the effect of bronchial artery embolization (BAE) with polyvinyl alcohol (PVA) foam and gelatinum sponge (GS) for serious hemoptysis. METHOD: Of 46 patients with severe hemoptysis, BAE with only GS was performed in 21 cases and with both PVA and GS in 25 cases. RESULT: The total efficacy rate of BAE was 91.3%; and comparable between PVA+GS and GS groups (92.0%; vs 90.5%;, P>0.05). The total recurrence rate after BAE was 26.2%;, but lower in PVA+GS group than in GS group (11.3%; vs 42.1%;, P<0.05). No serious complications occurred in these patients after BAE. CONCLUSION: BAE is effective and safe for management of serious hemoptysis, and treatment with PVA+GS may effectively lower the recurrence rate.


Assuntos
Embolização Terapêutica/métodos , Esponja de Gelatina Absorvível , Hemoptise/terapia , Álcool de Polivinil , Adolescente , Adulto , Idoso , Artérias Brônquicas , Bronquiectasia/complicações , Feminino , Seguimentos , Hemoptise/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
16.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 48(8): 453-7, 2013 Aug.
Artigo em Zh | MEDLINE | ID: mdl-24238408

RESUMO

OBJECTIVE: To investigate the effect of 30% hydrogen peroxide(HP) with different pH values on color, translucency and laser-induced fluorescence of human dentin. METHODS: Sixty dentin specimens from crown of mandibular third molars were randomly assigned into four groups (n = 15) and treated with acidic 30% HP, neutral 30% HP, alkaline 30% HP and deionized water (control group), respectively. The bleaching process was 0.5 h×4 times, and time points for measuring were baseline (0), 0.5, 1 and 2 h. A colorimeter was employed to measure the L(*), a(*), b(*) coordinates of dentin against white, black and yellow background. Then the parameters of translucency, masking effects, chroma and whiteness were calculated. The dentinal laser-induced Raman/fluorescence spectra was recorded by a Raman spectrometer and the fluorescence intensity(FI) and FI% were calculated. RESULTS: ΔFI of acidic, neutral, alkaline 30% HP at 2 h were 9960.03 ± 2037.74, 8502.09 ± 1413.86, 8554.29 ± 1986.19. And ΔFI% were 84.60 ± 3.43, 84.89 ± 5.19, 86.72 ± 2.65, respectively. Repeated measure of ANOVA revealed that all parameters in the bleaching groups were significantly influenced by time (P < 0.001). Compared with control group, bleaching resulted significant change of ΔTP, Δchroma, Δwhiteness, ΔL(*), Δa(*), Δb(*), ΔE, ΔFI and ΔFI% (P < 0.001). There was no significant difference between three bleaching groups on ΔTP, Δmasking effects, Δchroma, Δwhiteness, ΔL(*), Δb(*), ΔE, ΔFI and ΔFI%. Correlation analysis demonstrated that FI was associated with chroma, a(*), b(*) and whiteness, respectively, and ΔFI was associated with ΔTP, Δmasking effects, Δwhiteness, Δchroma, Δb(*) and ΔE. CONCLUSIONS: 30% HP with different pH values could result in the same change of the color, translucency and laser-induced fluorescence of human dentin.Laser-induced fluorescence was associated with dentinal color and translucency, which might be a novel way to investigate the bleaching mechanism of dentin.


Assuntos
Cor , Dentina/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Clareadores Dentários/farmacologia , Colorimetria/métodos , Coroas , Dentina/anatomia & histologia , Fluorescência , Humanos , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Dente Serotino , Distribuição Aleatória , Análise Espectral Raman , Clareamento Dental/métodos , Clareadores Dentários/química
17.
World J Gastroenterol ; 18(48): 7341-7, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23326143

RESUMO

AIM: To compare early use of transjugular intrahepatic portosystemic shunt (TIPS) with endoscopic treatment (ET) for the prophylaxis of recurrent variceal bleeding. METHODS: In-patient data were collected from 190 patients between January 2007 and June 2010 who suffured from variceal bleeding. Patients who were older than 75 years; previously received surgical treatment or endoscopic therapy for variceal bleeding; and complicated with hepatic encephalopathy or hepatic cancer, were excluded from this research. Thirty-five cases lost to follow-up were also excluded. Retrospective analysis was done in 126 eligible cases. Among them, 64 patients received TIPS (TIPS group) while 62 patients received endoscopic therapy (ET group). The relevant data were collected by patient review or telephone calls. The occurrence of rebleeding, hepatic encephalopathy or other complications, survival rate and cost of treatment were compared between the two groups. RESULTS: During the follow-up period (median, 20.7 and 18.7 mo in TIPS and ET groups, respectively), rebleeding from any source occurred in 11 patients in the TIPS group as compared with 31 patients in the ET group (Kaplan-Meier analysis and log-rank test, P = 0.000). Rebleeding rates at any time point (6 wk, 1 year and 2 year) in the TIPS group were lower than in the ET group (Bonferroni correction α' = α/3). Eight patients in the TIPS group and 16 in the ET group died with the cumulative survival rates of 80.6% and 64.9% (Kaplan-Meier analysis and log-rank test χ(2) = 4.864, P = 0.02), respectively. There was no significant difference between the two groups with respect to 6-wk survival rates (Bonferroni correction α' = α/3). However, significant differences were observed between the two groups in the 1-year survival rates (92% and 79%) and the 2-year survival rates (89% and 64.9%) (Bonferroni correction α' = α/3). No significant differences were observed between the two treatment groups in the occurrence of hepatic encephalopathy (12 patients in TIPS group and 5 in ET group, Kaplan-Meier analysis and log-rank test, χ(2) = 3.103, P = 0.08). The average total cost for the TIPS group was higher than for ET group (Wilcxon-Mann Whitney test, 52 678 RMB vs 38,844 RMB, P < 0.05), but hospitalization frequency and hospital stay during follow-up period were lower (Wilcxon-Mann Whitney test, 0.4 d vs 1.3 d, P = 0.01; 5 d vs 19 d, P < 0.05). CONCLUSION: Early use of TIPS is more effective than endoscopic treatment in preventing variceal rebleeding and improving survival rate, and does not increase occurrence of hepatic encephalopathy.


Assuntos
Endoscopia/métodos , Varizes Esofágicas e Gástricas/cirurgia , Hemorragia Gastrointestinal/cirurgia , Derivação Portossistêmica Transjugular Intra-Hepática/métodos , Adulto , Idoso , Cianoacrilatos/química , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Feminino , Seguimentos , Humanos , Hipertensão Portal , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Recidiva , Fatores de Tempo , Resultado do Tratamento
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