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1.
Arch Pharm Res ; 47(1): 20-39, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38151648

RESUMEN

Ocular diseases are a growing global concern and have a significant impact on the quality of life. Cataracts, glaucoma, age-related macular degeneration, and diabetic retinopathy are the most prevalent ocular diseases. Their prevalence and the global market size are also increasing. However, the available pharmacotherapy is currently limited. These diseases share common pathophysiological features, including neovascularization, inflammation, and/or neurodegeneration. Histone deacetylases (HDACs) are a class of enzymes that catalyze the removal of acetyl groups from lysine residues of histone and nonhistone proteins. HDACs are crucial for regulating various cellular processes, such as gene expression, protein stability, localization, and function. They have also been studied in various research fields, including cancer, inflammatory diseases, neurological disorders, and vascular diseases. Our study aimed to investigate the relationship between HDACs and ocular diseases, to identify a new strategy for pharmacotherapy. This review article explores the role of HDACs in ocular diseases, specifically focusing on diabetic retinopathy, age-related macular degeneration, and retinopathy of prematurity, as well as optic nerve disorders, such as glaucoma and optic neuropathy. Additionally, we explore the interplay between HDACs and key regulators of fibrosis and angiogenesis, such as TGF-ß and VEGF, highlighting the potential of targeting HDAC as novel therapeutic strategies for ocular diseases.


Asunto(s)
Retinopatía Diabética , Glaucoma , Degeneración Macular , Recién Nacido , Humanos , Retinopatía Diabética/tratamiento farmacológico , Histona Desacetilasas/metabolismo , Calidad de Vida , Glaucoma/tratamiento farmacológico , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/uso terapéutico , Inhibidores de Histona Desacetilasas/química
2.
Comput Methods Programs Biomed ; 242: 107853, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37857025

RESUMEN

BACKGROUND AND OBJECTIVE: Despite recent development of AI, prediction of the surgical movement in the maxilla and mandible by OGS might be more difficult than that of tooth movement by orthodontic treatment. To evaluate the prediction accuracy of the surgical movement using pairs of pre-(T0) and post-surgical (T1) lateral cephalograms (lat-ceph) of orthognathic surgery (OGS) patients and dual embedding module-graph convolution neural network (DEM-GCNN) model. METHODS: 599 pairs from 3 institutions were used as training, internal validation, and internal test sets and 201 pairs from other 6 institutions were used as external test set. DEM-GCNN model (IEM, learning the lat-ceph images; LTEM, learning the landmarks) was developed to predict the amount and direction of surgical movement of ANS and PNS in the maxilla and B-point and Md1crown in the mandible. The distance between T1 landmark coordinates actually moved by OGS (ground truth) and predicted by DEM-GCNN model and pre-existed CNN-based Model-C (learning the lat-ceph images) was compared. RESULTS: In both internal and external tests, DEM-GCNN did not exhibit significant difference from ground truth in all landmarks (ANS, PNS, B-point, Md1crown, all P > 0.05). When the accumulated successful detection rate for each landmark was compared, DEM-GCNN showed higher values than Model-C in both the internal and external tests. In violin plots exhibiting the error distribution of the prediction results, both internal and external tests showed that DEM-GCNN had significant performance improvement in PNS, ANS, B-point, Md1crown than Model-C. DEM-GCNN showed significantly lower prediction error values than Model-C (one-jaw surgery, B-point, Md1crown, all P < 0.005; two-jaw surgery, PNS, ANS, all P < 0.05; B point, Md1crown, all P < 0.005). CONCLUSION: We developed a robust OGS planning model with maximized generalizability despite diverse qualities of lat-cephs from 9 institutions.


Asunto(s)
Mandíbula , Procedimientos Quirúrgicos Ortognáticos , Humanos , Cefalometría/métodos , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Procedimientos Quirúrgicos Ortognáticos/métodos , Maxilar/diagnóstico por imagen , Maxilar/cirugía
3.
J Craniomaxillofac Surg ; 51(5): 265-271, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37353406

RESUMEN

This study aimed to investigate the difference in facial reanimation surgery using functional gracilis muscle transfer between the masseteric nerve alone and its combined use with cross face nerve graft (CFNG), which has not been explored before. A novel analysis method based on artificial intelligence (AI) was employed to compare the outcomes of the two approaches. Using AI, 3-dimensional facial landmarks were extracted from 2-dimensional photographs, and distance and angular symmetry scores were calculated. The patients were divided into two groups, with Group 1 undergoing one-stage CFNG and masseteric nerve dual innervation, and Group 2 receiving only masseteric nerve. The symmetry scores were obtained before and 1 year after surgery to assess the degree of change. Of the 35 patients, Group 1 included 13 patients, and Group 2 included 22 patients. The analysis revealed that, in the resting state, the change in the symmetry score of the mouth corner showed distance symmetry (2.55 ± 2.94, 0.52 ± 2.75 for Group 1 and Group 2, respectively, p = 0.048) and angle symmetry (1.21 ± 1.43, 0.02 ± 0.22 for Group 1 and Group 2, respectively, p = 0.001), which were significantly improved in Group 1, indicating a more symmetric pattern after surgery. In the smile state, only the angle symmetry was improved more symmetrically in Group 1 (3.20 ± 2.38, 1.49 ± 2.22 for Group 1 and Group 2, respectively, p = 0.041). Within the limitations of the study it seems that this new analysis method enabled a more accurate numerical symmetry score to be obtained, and while the degree of mouth corner excursion was sufficient with only the masseteric nerve, accompanying CFNG led to further improvement in symmetry in the resting state.


Asunto(s)
Parálisis Facial , Transferencia de Nervios , Humanos , Parálisis Facial/cirugía , Estudios Retrospectivos , Inteligencia Artificial , Transferencia de Nervios/métodos , Sonrisa/fisiología , Nervio Facial/cirugía
4.
PLoS One ; 18(6): e0287512, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37379287

RESUMEN

The prevalence of dysphagia is increasing, resulting in socioeconomic burden, but previous reports have only been based on a limited populations. Therefore, we aimed to investigate the nationwide incidence and prevalence of dysphagia requiring medical attention to provide adequate information for healthcare planning and resource allocation. In this nationwide retrospective cohort study, the data of adults aged ≥20 years recorded from 2006 to 2016 were sourced from the Korean National Health Insurance Service database. Medical claim codes based on ICD-10-CM were used to define dysphagia and possible causes. The annual incidence and prevalence of dysphagia were calculated. Cox regression was used to estimate dysphagia risk in people with possible dysphagia etiology. Survival analysis was performed to estimate the mortality and hazard ratio of dysphagia. The crude annual incidence of dysphagia increased continuously from 7.14 in 2006 to 15.64 in 2016. The crude annual prevalence of dysphagia in 2006 was 0.09% and increased annually to 0.25% in 2016. Stroke (odds ratio [OR]: 7.86, 95% confidence interval [CI]: 5.76-6.68), neurodegenerative disease (OR: 6.20, 95% CI: 5.76-6.68), cancer (OR: 5.59, 95% CI: 5.17-6.06), and chronic obstructive pulmonary disease (OR: 2.94, 95% CI: 2.71-3.18) were associated with a high risk of dysphagia. The mortality in the dysphagia group was 3.12 times higher than that in the non-dysphagia group (hazard ratio: 3.12, 95% CI: 3.03-3.23). The incidence and prevalence of dysphagia requiring medical attention are increasing annually. The increasing trend was conspicuous in the geriatric population. The presence of stroke, neurodegenerative disease, cancer, and chronic obstructive pulmonary disease is associated with a high risk of dysphagia. Therefore, adequate screening, diagnosis, and management of dysphagia in the older population must be emphasized in geriatric healthcare.


Asunto(s)
Trastornos de Deglución , Neoplasias , Enfermedades Neurodegenerativas , Enfermedad Pulmonar Obstructiva Crónica , Accidente Cerebrovascular , Adulto , Humanos , Anciano , Incidencia , Prevalencia , Estudios Retrospectivos , Trastornos de Deglución/epidemiología , República de Corea/epidemiología
5.
J Pathol Transl Med ; 57(2): 113-122, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36950813

RESUMEN

BACKGROUND: Gallbladder cancer (GBC) is usually detected in advanced stages with a low 5-year survival rate. Delta-like ligand 4 (DLL4), vascular endothelial growth factor (VEGF), and hypoxia-inducible factor-2alpha (HIF2α) have been studied for their role in tumorigenesis and potential for therapeutic target, and multiple clinical trials of the agents targeting them are ongoing. We investigated the expression of these markers in surgically resected GBC and tried to reveal their association with the clinicopathologic features, mutual correlation of their expression, and prognosis of the GBC patients by their expression. METHODS: We constructed the tissue microarray blocks of 99 surgically resected GBC specimens and performed immunohistochemistry of DLL4, VEGF, and HIF2α. We used the quantitative digital image analysis to evaluate DLL4 and VEGF expression, while the expression of HIF2α was scored manually. RESULTS: The expression of VEGF and HIF2α showed a significant trend with tumor differentiation (p= .028 and p= .006, respectively). We found that the high DLL4 and VEGF expression were significantly correlated with lymph node metastasis (p= .047, both). The expression of VEGF and HIF2α were significantly correlated (p < .001). The GBC patients with low HIF2α expression showed shorter recurrence-free survival than those with high HIF2α expression. CONCLUSIONS: This study suggested the possibility of the usage of DLL4 and VEGF to predict the lymph node metastasis and the possibility of VEGF and HIF2α to predict the expression level mutually. Further studies may be needed to validate our study results and eventually accelerate the introduction of the targeted therapy in GBC.

6.
Anticancer Res ; 41(11): 5489-5498, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34732419

RESUMEN

BACKGROUND/AIM: Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is known to show uneven distribution and penetration of agents based on the nozzle position. Thus, this study aimed to investigate the ideal nozzle position for maximizing drug delivery during PIPAC. MATERIALS AND METHODS: We created 2 cm-, 4 cm- and 8 cm-ex vivo models according to the distance from the bottom to the nozzle using 21×15×16 cm-sized sealable plastic boxes. After each set of eight normal peritoneal tissues from swine were placed at eight different points (A to H), we performed PIPAC, compared the methylene blue staining areas to investigate the distribution, and estimated the depth of concentrated diffusion (DCD) and the depth of maximal diffusion (DMD) of doxorubicin. RESULTS: In terms of distribution, the 4 cm- and 8 cm-ex vivo models showed more stained faces than the 2 cm-ex vivo model. Regarding the penetration depth, the 4 cm- ex vivo model showed the highest DCD (mean; 244.1 µm, C; 105.1 µm, D; 80.9 µm, E; 250.2 µm, G; 250.2 µm, H) and DMD (mean; 174.8 µm, D; 162.7 µm, E; 511.7 µm, F; 522.2 µm, G; 528.1 µm, H) in the most points corresponding to 62.5%. CONCLUSION: The ideal nozzle position during PIPAC might be halfway between the nozzle inlet and the bottom in the ex vivo model.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/instrumentación , Neoplasias Peritoneales/tratamiento farmacológico , Peritoneo/metabolismo , Aerosoles , Animales , Antibióticos Antineoplásicos/metabolismo , Antineoplásicos/metabolismo , Difusión , Doxorrubicina/metabolismo , Diseño de Equipo , Presión , Sus scrofa , Distribución Tisular
7.
Sci Rep ; 11(1): 17512, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34471219

RESUMEN

This study aimed to evaluate the biocompatibility and patency of our newly developed titanium vascular anastomotic device (TVAD) in a pig jugular vein. TVAD was made of commercially pure grade 2 titanium. The patency and anastomotic time were simultaneously confirmed in an ex-vivo system developed by the authors and in vivo using pig jugular veins. Five 8-month-old pigs, with body weights of 50-60 kg, underwent anastomosis of both jugular veins using the device. Graft patency was evaluated for 12 weeks by biplane angiography and sonography. All tissue biopsy samples were analysed by histology. In all 10 cases, the anastomosis was completed in < 5 min. The vessel lumen was not damaged, and the inner vessel wall was completely endothelialised at the anastomotic site. No foreign body reactions were observed at the vessel lumen, vessels, and outer vessel walls by histopathologic analysis. Patency and absence of leakage at the anastomotic site of the follow-up period were confirmed clearly by angiography and sonography. This preliminary animal study proved that our newly developed device is a very promising tool for intima-to-intima contact anastomosis. TVAD can be used as a feasible and safe medical tool for vessel anastomosis.


Asunto(s)
Anastomosis Quirúrgica/instrumentación , Implantación de Prótesis Vascular/instrumentación , Venas Yugulares/cirugía , Ensayo de Materiales/métodos , Titanio/química , Grado de Desobstrucción Vascular , Anastomosis Quirúrgica/métodos , Animales , Venas Yugulares/patología , Modelos Animales , Porcinos
8.
Theranostics ; 11(18): 8855-8873, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34522215

RESUMEN

Mitochondrial dysfunction and oxidative stress are frequently observed in the early stages of Alzheimer's disease (AD). Studies have shown that presenilin-1 (PS1), the catalytic subunit of γ-secretase whose mutation is linked to familial AD (FAD), localizes to the mitochondrial membrane and regulates its homeostasis. Thus, we investigated how five PS1 mutations (A431E, E280A, H163R, M146V, and Δexon9) observed in FAD affect mitochondrial functions. Methods: We used H4 glioblastoma cell lines genetically engineered to inducibly express either the wild-type PS1 or one of the five PS1 mutants in order to examine mitochondrial morphology, dynamics, membrane potential, ATP production, mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs), oxidative stress, and bioenergetics. Furthermore, we used brains of PS1M146V knock-in mice, 3xTg-AD mice, and human AD patients in order to investigate the role of PS1 in regulating MAMs formation. Results: Each PS1 mutant exhibited slightly different mitochondrial dysfunction. Δexon9 mutant induced mitochondrial fragmentation while A431E, E280A, H163R, and M146V mutants increased MAMs formation. A431E, E280A, M146V, and Δexon9 mutants also induced mitochondrial ROS production. A431E mutant impaired both complex I and peroxidase activity while M146V mutant only impaired peroxidase activity. All PS1 mutants compromised mitochondrial membrane potential and cellular ATP levels were reduced by A431E, M146V, and Δexon9 mutants. Through comparative profiling of hippocampal gene expression in PS1M146V knock-in mice, we found that PS1M146V upregulates Atlastin 2 (ATL2) expression level, which increases ER-mitochondria contacts. Down-regulation of ATL2 after PS1 mutant induction rescued abnormally elevated ER-mitochondria interactions back to the normal level. Moreover, ATL2 expression levels were significantly elevated in the brains of 3xTg-AD mice and AD patients. Conclusions: Overall, our findings suggest that each of the five FAD-linked PS1 mutations has a deleterious effect on mitochondrial functions in a variety of ways. The adverse effects of PS1 mutations on mitochondria may contribute to MAMs formation and oxidative stress resulting in an accelerated age of disease onset in people harboring mutant PS1.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Mitocondrias/fisiología , Presenilina-1/genética , Adenosina Trifosfato/metabolismo , Enfermedad de Alzheimer/genética , Animales , Línea Celular Tumoral , Retículo Endoplásmico/metabolismo , Técnicas de Sustitución del Gen/métodos , Humanos , Potencial de la Membrana Mitocondrial/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mutación , Estrés Oxidativo/fisiología , Presenilina-1/metabolismo
9.
Drug Deliv ; 28(1): 1179-1187, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34121568

RESUMEN

This study aims to evaluate the drug distribution, tissue concentrations, penetration depth, pharmacokinetic properties, and toxicities after rotational intraperitoneal pressurized aerosol chemotherapy (RIPAC) in pigs. Because relevant medical devices have not been introduced, we developed our prototype of pressurized intraperitoneal aerosol chemotherapy (PIPAC) and RIPAC by adding a conical pendulum motion device for rotating the nozzle. RIPAC and PIPAC were conducted using 150 ml of 1% methylene blue to evaluate the drug distribution and 3.5 mg of doxorubicin in 50 ml of 0.9% NaCl to evaluate the tissue concentrations and penetration depth, pharmacokinetic properties, and toxicities. All agents were sprayed as aerosols via the nozzle, DreamPen® (Dalim Biotech, Gangwon, South Korea), with a velocity of 5 km/h at a flow rate of 30 ml/min under a pressure of 7 bars, and capnoperitoneum of 12 mmHg was maintained for 30 min. As a result, RIPAC showed a wider distribution and stronger intensity than PIPAC. Compared with PIPAC, RIPAC demonstrated high values of the tissue concentration in the central, right upper, epigastrium, left upper, left lower, right lower, and right flank regions (median, 375.5-2124.9 vs. 161.7-1240 ng/ml; p ≤ .05), and higher values of the depth of concentrated diffusion and depth of maximal diffusion (median, 232.5-392.7 vs. 116.9-240.1 µm; 291.2-551.2 vs. 250.5-362.4 µm; p ≤ .05) in all regions except for bowels. In RIPAC, the pharmacokinetic properties reflected hemodynamic changes during capnoperitoneum, and there were no related toxicities. Conclusively, RIPAC may have the potential to enhance drug delivery into the peritoneum compared to PIPAC.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/farmacocinética , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacocinética , Sistemas de Liberación de Medicamentos/métodos , Peritoneo/efectos de los fármacos , Aerosoles , Animales , Antibióticos Antineoplásicos/efectos adversos , Doxorrubicina/efectos adversos , Porcinos
10.
Acta Biomater ; 125: 242-252, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33657454

RESUMEN

Bacterial infections and the formation of biofilms on the surface of implantable medical devices are critical issues that cause device failure. Implantable medical devices, such as drug delivery technologies, offer promising benefits for targeted and prolonged drug release, but a number of common disadvantages arise that include inadequate release and side effects. Organic film coatings for antifouling and drug delivery are expected to overcome these challenges. Ferrocene polymer-based multifunctional multilayer films were prepared to control the reactive oxygen species (ROS)-responsive release of therapeutic agents while maintaining an antifouling effect and improving biocompatibility. Polymers based on ferrocene and polyethylene glycol were prepared by controlling the molar ratio of carboxylate and amine groups. Layer-by-layer deposition was optimized to achieve the linear growth and self-assembly of dense and stable films. Outstanding anti-biofilm activity (~91% decrease) could be achieved and the films were found to be blood compatible. Importantly, the films effectively incorporated hydrophobic drugs and exhibited dual-responsive drug release at low pH and under ROS conditions at physiological pH. Drug delivery to MCF-7 breast cancer cells was achieved using a Paclitaxel loaded film, which exhibited an anticancer efficacy of 62%. STATEMENT OF SIGNIFICANCE: Healthcare associated infection is caused by the formation of a biofilm by bacteria on the surface of a medical device. In order to solve this, extensive research has been conducted on many coating technologies. Also, a method of chemical treatment by releasing the drug when it enters the body by loading the drug into the coating film is being studied. However, there is still a lack of technology that can achieve both functions of preventing biofilm production and drug delivery. Therefore, in this study, a multilayer thin film that supports drug and inhibits biofilm formation was prepared through Layer-by-Layer coating of a polymer containing PEG to prevent adsorption. As such, it helps the design of multifunctional coatings for implantable medical devices.


Asunto(s)
Polímeros , Staphylococcus aureus , Materiales Biocompatibles Revestidos/farmacología , Preparaciones de Acción Retardada , Metalocenos , Prótesis e Implantes , Especies Reactivas de Oxígeno
11.
Cancers (Basel) ; 12(3)2020 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-32182896

RESUMEN

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) has been suggested as an alternative option for treating peritoneal carcinomatosis (PC). Even with its clinical advantages, the current PIPAC system still suffers from limitations regarding drug distribution area and penetration depth. Thus, we evaluated the new PIPAC system using a novel prototype, and compared its performance to the results from previous studies related with the current MIP® indirectly because the system is currently not available for purchase in the market. The developed prototype includes a syringe pump, a nozzle, and controllers. Drug distribution was conducted using a methylene blue solution for performance test. For penetration depth evaluation, an ex-vivo experiment was performed with porcine tissues in a 3.5 L plastic box. Doxorubicin was sprayed using the novel prototype, and its penetration depth was investigated by confocal laser scanning microscopy. The experiment was repeated with varying nozzle levels from the bottom. The novel prototype sprays approximately 30 µm drug droplets at a flow rate of 30 mL/min with 7 bars of pressure. The average diameter of sprayed region with concentrated dye was 18.5 ± 1.2 cm, which was comparable to that of the current MIP® (about 10 cm). The depth of concentrated diffusion (DCD) did not differ among varying nozzle levels, whereas the depth of maximal diffusion (DMD) decreased with increasing distance between the prototype and the bottom (mean values, 515.3 µm at 2 cm; 437.6 µm at 4 cm; 363.2 µm at 8 cm), which was comparable to those of the current MIP® (about 350-500 µm). We developed a novel prototype that generate small droplets for drug aerosolization and that have a comparably wide sprayed area and depth of penetration to the current MIP® at a lower pressure.

12.
ACS Appl Mater Interfaces ; 11(28): 25322-25329, 2019 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-31268653

RESUMEN

Pure and 3-12 at. % Pr-doped In2O3 macroporous spheres were fabricated by ultrasonic spray pyrolysis and their acetone-sensing characteristics under dry and humid conditions were investigated to design humidity-independent gas sensors. The 12 at. % Pr-doped In2O3 sensor exhibited approximately the same acetone responses and sensor resistances at 450 °C regardless of the humidity variation, whereas the pure In2O3 exhibited significant deterioration in gas-sensing characteristics upon the change in the atmosphere, from dry to humid (relative humidity: 80%). Moreover, the 12 at. % Pr-doped In2O3 sensor exhibited a high response to acetone with negligible cross responses to interfering gases (NH3, CO, benzene, toluene, NO2, and H2) under the highly humid atmosphere. The mechanism for the humidity-immune gas-sensing characteristics was investigated by X-ray photoelectron and diffuse reflectance infrared Fourier transform spectroscopies together with the phenomenological gas-sensing results and discussed in relation with Pr3+/Pr4+ redox pairs, regenerative oxygen adsorption, and scavenging of hydroxyl groups.

13.
ACS Appl Mater Interfaces ; 9(47): 41397-41404, 2017 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-29112803

RESUMEN

Co3O4 sensors with a nanoscale TiO2 or SnO2 catalytic overlayer were prepared by screen-printing of Co3O4 yolk-shell spheres and subsequent e-beam evaporation of TiO2 and SnO2. The Co3O4 sensors with 5 nm thick TiO2 and SnO2 overlayers showed high responses (resistance ratios) to 5 ppm xylene (14.5 and 28.8) and toluene (11.7 and 16.2) at 250 °C with negligible responses to interference gases such as ethanol, HCHO, CO, and benzene. In contrast, the pure Co3O4 sensor did not show remarkable selectivity toward any specific gas. The response and selectivity to methylbenzenes and ethanol could be systematically controlled by selecting the catalytic overlayer material, varying the overlayer thickness, and tuning the sensing temperature. The significant enhancement of the selectivity for xylene and toluene was attributed to the reforming of less reactive methylbenzenes into more reactive and smaller species and oxidative filtering of other interference gases, including ubiquitous ethanol. The concurrent control of the gas reforming and oxidative filtering processes using a nanoscale overlayer of catalytic oxides provides a new, general, and powerful tool for designing highly selective and sensitive oxide semiconductor gas sensors.

14.
Analyst ; 129(1): 87-91, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14737589

RESUMEN

The monoclonal antibody (MAb) against berberine, a bioactive constituent of Coptis japonica M., Phellodendron amurense R. and Hydrastis canadensis L., was produced and characterized. As immunogen, the derivative of berberine, 9-O-carboxymethyl berberrubine was synthesized and conjugated to carrier protein, bovine serum albumin (BSA). In order to confirm its immunogenicity, the ratio of hapten in berberine-BSA conjugate was determined by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). After immunization, hybridomas secreting MAbs against berberine were produced by fusing splenocytes with mouse myeloma cell line, P3-X63-Ag8-653. After the screening, anti-berberine MAb 1D5-3B-7 was obtained. Subsequently, a quantitative ELISA system for berberine and its related compounds using the MAb was established and evaluated comparing with HPLC method. The ELISA method described in this study can be available as an analytical tool for quality control and standardization of medicinal plants and its prescriptions containing berberine and its related compounds.


Asunto(s)
Berberina/análisis , Medicina de Hierbas , Animales , Anticuerpos Monoclonales/inmunología , Berberina/inmunología , Cromatografía Líquida de Alta Presión , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C
15.
Cytotechnology ; 44(3): 115-23, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19003234

RESUMEN

In the development of immunoassay technique, the design of hapten containing a functional group suitable for protein conjugate is the key step for the preparation of antibodies against small molecules. Coptisine (MW 320), a bioactive constituent of Berberis and Coptis species, is small as an immunogen. In addition, coptisine has no reactive group in molecule for conjugating with a protein. To overcome this problem, 9-O-carboxymethyl-berberrubine was designed and conjugated with carrier protein. In order to confirm its immunogenicity, the ratio of hapten in the conjugate was determined by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). After immunization, hybridomas secreting antibodies against coptisine were produced by fusing splenocytes with mouse myeloma cell line, P3-X63-Ag8-653. Among hybridomas, the clone 2A1 secreting anti-coptisine monoclonal antibody (MAb) 2A1-9E-1 was obtained through the limited dilution method. The MAb-based enzyme-linked immunosorbent assay (ELISA) against coptisine was developed and characterized. The linear range of the assay in this ELISA method was extended from 1.56 to 25 mug ml(-1) possessing the detection limit of 1.56 mug ml(-1). The established ELISA using MAb 2A1-9E-1 was applied for the survey of isoquinoline alkaloids in various medicinal plants.

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