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1.
J Oral Rehabil ; 49(2): 237-248, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34075611

RESUMEN

BACKGROUND: Oro-facial pain is more prevalent in women than in men, and oestrogen may underlie this sex difference. Genistein reversed the potentiation of 17ß-estradiol (E2) on glutamate-induced acute masseter nociceptive behaviour, but its role in dental experimental occlusal interference (EOI)-induced chronic masseter hyperalgesia remains unclear. OBJECTIVE: This study aimed to investigate sex differences, and to explore the role and underlying mechanisms of genistein in E2-potentiated EOI-induced chronic masseter hyperalgesia in rats. METHODS: Female and male rats were prepared to compare the sex differences of masseter hyperalgesia induced by EOI using a 0.4-mm-thick metal crown. Female rats were ovariectomised (OVX) and treated with E2 and genistein, followed by EOI. The head withdrawal threshold (HWT) was examined to assess masseter sensitivity. The protein expression of transient receptor potential vanilloid-1 (TRPV1) in the trigeminal ganglion (TG) was detected using western blotting. Immunofluorescence staining was used to reveal the colocalisation of oestrogen receptors (ERs) with TRPV1 and the percentage of TRPV1-positive neurons in the TG. RESULTS: To some extent, female rats displayed enhanced sensitivity to EOI-induced chronic masseter hyperalgesia compared with males. Female rats showed the lowest HWT in the pro-oestrus phase. Pre-treatment with genistein antagonised E2 potentiation in EOI-induced masseter hyperalgesia and blocked the effect of E2 by downregulating TRPV1 protein expression and the percentage of TRPV1-positive neurons in the TG. CONCLUSION: Female rats showed greater masseter hyperalgesia than males under EOI. Genistein antagonised the facilitation of EOI-induced chronic masseter hyperalgesia by E2 probably through inhibiting TRPV1 in the TG.


Asunto(s)
Genisteína , Hiperalgesia , Animales , Estradiol/farmacología , Femenino , Genisteína/farmacología , Hiperalgesia/tratamiento farmacológico , Masculino , Músculo Masetero , Ratas , Ratas Sprague-Dawley
2.
Int J Mol Sci ; 23(10)2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35628439

RESUMEN

Bone substitutes with strong antibacterial properties and bone regeneration effects have an inherent potential in the treatment of severe bone tissue infections, such as osteomyelitis. In this study, vancomycin (Van) was loaded into zeolitic imidazolate framework-8 (ZIF-8) to prepare composite particles, which is abbreviated as V@Z. As a pH-responsive particle, ZIF-8 can be cleaved in the weak acid environment caused by bacterial infection to realize the effective release of drugs. Then, V@Z was loaded into polyvinyl alcohol (PVA) fiber by electrospinning to prepare PVA/V@Z composite bone filler. The drug-loading rate of V@Z was about 6.735%. The membranes exhibited super hydrophilicity, water absorption and pH-controlled Van release behavior. The properties of anti E. coli and S. aureus were studied under the pH conditions of normal physiological tissues and infected tissues (pH 7.4 and pH 6.5, respectively). It was found that the material had good surface antibacterial adhesion and antibacterial property. The PVA/V@Z membrane had the more prominent bacteria-killing effect compared with the same amount of single antibacterial agent containing membrane such as ZIF-8 or Van loaded PVA, and the antibacterial rate was up to 99%. The electrospun membrane had good biocompatibility and can promote MC3T3-E1 cell spreading on it.


Asunto(s)
Nanofibras , Zeolitas , Antibacterianos/química , Antibacterianos/farmacología , Escherichia coli , Nanofibras/química , Alcohol Polivinílico/química , Staphylococcus aureus , Vancomicina/farmacología
3.
Gastroenterol Nurs ; 45(6): 428-439, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35758925

RESUMEN

The quality of bowel preparation is an extremely important determinant of colonoscopy results. However, the efficacy of senna regimens in improving bowel cleanliness is uncertain. We conducted a systematic review and meta-analysis to synthesize data on whether using a senna bowel preparation regimen enhances the bowel cleanliness. We searched Web of Science Core Collection, MEDLINE, PubMed, Embase, Cochrane Library, and Scopus databases (from the inception to August 2021). The primary efficacy outcome was bowel cleanliness. Secondary outcomes included patient compliance, tolerance, and adverse events. Eleven trials fulfilled the inclusion criteria (3,343 patients. Overall, we found no significant differences in bowel cleanliness between the senna regimen and other bowel preparation regimens (odds ratio [95% confidence interval]: 1.02 [0.63, 1.67], p = 0.93). There was significant difference in tolerance (odds ratio [95% confidence interval]: 1.66 [1.08, 2.54], p = .02) and compliance (odds ratio [95% confidence interval]: 3.05 [1.42, 6.55], p = .004). The senna regimen yielded a significantly greater proportion of no nausea (odds ratio [95% confidence interval]: 1.84 [1.45, 2.32]) and vomiting (odds ratio [95% confidence interval]: 1.65 [0.81, 3.35]). Compared with other bowel preparation regimens, the senna regimen may be effective and safe in bowel cleaning before colonoscopy, with superior compliance and tolerance.


Asunto(s)
Catárticos , Colonoscopía , Humanos , Colonoscopía/métodos , Senósidos , Cooperación del Paciente , Polietilenglicoles
4.
Biomed Eng Online ; 20(1): 15, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33546713

RESUMEN

BACKGROUND: The objective of the study was to validate biomechanical characteristics of a 3D-printed, novel-designated fixation plate for treating mandibular angle fracture, and compare it with two commonly used fixation plates by finite element (FE) simulations and experimental testing. METHODS: A 3D virtual mandible was created from a patient's CT images as the master model. A custom-designed plate and two commonly used fixation plates were reconstructed onto the master model for FE simulations. Modeling of angle fracture, simulation of muscles of mastication, and defining of boundary conditions were integrated into the theoretical model. Strain levels during different loading conditions were analyzed using a finite element method (FEM). For mechanical test design, samples of the virtual mandible with angle fracture and the custom-designed fixation plates were printed using selective laser sintering (SLS) and selective laser melting (SLM) printing methods. Experimental data were collected from a testing platform with attached strain gauges to the mandible and the plates at different 10 locations during mechanical tests. Simulation of muscle forces and temporomandibular joint conditions were built into the physical models to improve the accuracy of clinical conditions. The experimental vs the theoretical data collected at the 10 locations were compared, and the correlation coefficient was calculated. RESULTS: The results show that use of the novel-designated fixation plate has significant mechanical advantages compared to the two commonly used fixation plates. The results of measured strains at each location show a very high correlation between the physical model and the virtual mandible of their biomechanical behaviors under simulated occlusal loading conditions when treating angle fracture of the mandible. CONCLUSIONS: Based on the results from our study, we validate the accuracy of our computational model which allows us to use it for future clinical applications under more sophisticated biomechanical simulations and testing.


Asunto(s)
Placas Óseas , Análisis de Elementos Finitos , Fijación Interna de Fracturas/instrumentación , Fracturas Mandibulares/cirugía , Fenómenos Biomecánicos , Humanos , Estrés Mecánico
5.
Int J Mol Sci ; 22(13)2021 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-34203300

RESUMEN

Pain symptoms in temporomandibular disorders (TMD) predominantly affect reproductive women, suggesting that estrogen regulates pain perception. However, how estrogen contributes to chronic TMD pain remains largely unclear. In the present study, we performed behavioral tests, electrophysiology, Western blot and immunofluorescence to investigate the role and underlying mechanisms of estrogen in dental experimental occlusal interference (EOI)-induced chronic masseter mechanical hyperalgesia in rats. We found that long-term 17ß-estradiol (E2) replacement exacerbated EOI-induced masseter hyperalgesia in a dose-dependent manner in ovariectomized (OVX) rats. Whole-cell patch-clamp recordings demonstrated that E2 (100 nM) treatment enhanced the excitability of isolated trigeminal ganglion (TG) neurons in OVX and OVX EOI rats, and EOI increased the functional expression of transient receptor potential vanilloid-1 (TRPV1). In addition, E2 replacement upregulated the protein expression of TRPV1 in EOI-treated OVX rats. Importantly, intraganglionic administration of the TRPV1 antagonist AMG-9810 strongly attenuated the facilitatory effect of E2 on EOI-induced masseter mechanical sensitivity. These results demonstrate that E2 exacerbated EOI-induced chronic masseter mechanical hyperalgesia by increasing TG neuronal excitability and TRPV1 function. Our study helps to elucidate the E2 actions in chronic myogenic TMD pain and may provide new therapeutic targets for relieving estrogen-sensitive pain.


Asunto(s)
Hiperalgesia/tratamiento farmacológico , Neuronas Aferentes/efectos de los fármacos , Canales Catiónicos TRPV/metabolismo , Ganglio del Trigémino/metabolismo , Acrilamidas/farmacología , Animales , Western Blotting , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Estradiol/genética , Estradiol/metabolismo , Femenino , Técnica del Anticuerpo Fluorescente , Hiperalgesia/metabolismo , Ovariectomía , Ratas , Ratas Sprague-Dawley , Ganglio del Trigémino/efectos de los fármacos
6.
Mar Drugs ; 17(5)2019 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-31083588

RESUMEN

Refractory wound healing is one of the most common complications of diabetes. Excessive production of reactive oxygen species (ROS) can cause chronic inflammation and thus impair cutaneous wound healing. Scavenging these ROS in wound dressing may offer effective treatment for chronic wounds. Here, a nanocomposite hydrogel based on alginate and positively charged Eudragit nanoparticles containing edaravone, an efficient free radical scavenger, was developed for maximal ROS sequestration. Eudragit nanoparticles enhanced edaravone solubility and stability breaking the limitations in application. Furthermore, loading these Eudragit nanoparticles into an alginate hydrogel increased the protection and sustained the release of edaravone. The nanocomposite hydrogel is shown to promote wound healing in a dose-dependent way. A low dose of edaravone-loaded nanocomposite hydrogel accelerated wound healing in diabetic mice. On the contrary, a high dose of edaravone might hamper the healing. Those results indicated the dual role of ROS in chronic wounds. In addition, the discovery of this work pointed out that dose could be the key factor limiting the translational application of antioxidants in wound healing.


Asunto(s)
Alginatos/administración & dosificación , Hidrogeles/administración & dosificación , Nanocompuestos/administración & dosificación , Nanopartículas/administración & dosificación , Cicatrización de Heridas/efectos de los fármacos , Alginatos/química , Animales , Materiales Biocompatibles/administración & dosificación , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Hidrogeles/química , Masculino , Ratones , Ratones Endogámicos C57BL , Nanocompuestos/química , Nanopartículas/química , Distribución Aleatoria , Especies Reactivas de Oxígeno/metabolismo
7.
Biomed Eng Online ; 16(1): 131, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29141673

RESUMEN

BACKGROUND: The purpose of this study was to design a customized fixation plate for mandibular angle fracture using topological optimization based on the biomechanical properties of the two conventional fixation systems, and compare the results of stress, strain and displacement distributions calculated by finite element analysis (FEA). METHODS: A three-dimensional (3D) virtual mandible was reconstructed from CT images with a mimic angle fracture and a 1 mm gap between two bone segments, and then a FEA model, including volume mesh with inhomogeneous bone material properties, three loading conditions and constraints (muscles and condyles), was created to design a customized plate using topological optimization method, then the shape of the plate was referenced from the stress concentrated area on an initial part created from thickened bone surface for optimal calculation, and then the plate was formulated as "V" pattern according to dimensions of standard mini-plate finally. To compare the biomechanical behavior of the "V" plate and other conventional mini-plates for angle fracture fixation, two conventional fixation systems were used: type A, one standard mini-plate, and type B, two standard mini-plates, and the stress, strain and displacement distributions within the three fixation systems were compared and discussed. RESULTS: The stress, strain and displacement distributions to the angle fractured mandible with three different fixation modalities were collected, respectively, and the maximum stress for each model emerged at the mandibular ramus or screw holes. Under the same loading conditions, the maximum stress on the customized fixation system decreased 74.3, 75.6 and 70.6% compared to type A, and 34.9, 34.1, and 39.6% compared to type B. All maximum von Mises stresses of mandible were well below the allowable stress of human bone, as well as maximum principal strain. And the displacement diagram of bony segments indicated the effect of treatment with different fixation systems. CONCLUSIONS: The customized fixation system with topological optimized structure has good biomechanical behavior for mandibular angle fracture because the stress, strain and displacement within the plate could be reduced significantly comparing to conventional "one mini-plate" or "two mini-plates" systems. The design methodology for customized fixation system could be used for other fractures in mandible or other bones to acquire better mechanical behavior of the system and improve stable environment for bone healing. And together with SLM, the customized plate with optimal structure could be designed and fabricated rapidly to satisfy the urgent time requirements for treatment.


Asunto(s)
Placas Óseas , Análisis de Elementos Finitos , Fracturas Mandibulares/cirugía , Diseño de Prótesis/métodos , Fenómenos Biomecánicos , Humanos , Fracturas Mandibulares/diagnóstico por imagen , Estrés Mecánico , Tomografía Computarizada por Rayos X
8.
J Biomech Eng ; 139(12)2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28816344

RESUMEN

The method used in biomechanical modeling for finite element method (FEM) analysis needs to deliver accurate results. There are currently two solutions used in FEM modeling for biomedical model of human bone from computerized tomography (CT) images: one is based on a triangular mesh and the other is based on the parametric surface model and is more popular in practice. The outline and modeling procedures for the two solutions are compared and analyzed. Using a mandibular bone as an example, several key modeling steps are then discussed in detail, and the FEM calculation was conducted. Numerical calculation results based on the models derived from the two methods, including stress, strain, and displacement, are compared and evaluated in relation to accuracy and validity. Moreover, a comprehensive comparison of the two solutions is listed. The parametric surface based method is more helpful when using powerful design tools in computer-aided design (CAD) software, but the triangular mesh based method is more robust and efficient.


Asunto(s)
Análisis de Elementos Finitos , Mandíbula , Fenómenos Mecánicos , Fenómenos Biomecánicos , Imagenología Tridimensional , Mandíbula/diagnóstico por imagen , Mandíbula/fisiología , Rango del Movimiento Articular , Tomografía Computarizada por Rayos X
9.
Food Chem ; 459: 140378, 2024 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38991446

RESUMEN

In this study, a hydrothermal process was utilized to grow mixed-valence CuFe2O4/Cu0 nanosheets on carbon fiber paper, forming a three-dimensional hierarchical electrode (CuFe2O4/Cu0@CFP). The ordered array structure, coupled with the porous bowl-like structure, enhances the exposure of more electrode active sites and facilitates analyte penetration, thus enhancing the electrode sensing performance. As a binder-free sensor, the CuFe2O4/Cu0@CFP sensor exhibited remarkable sensitivity in detecting Malachite Green (MG), Sunset Yellow (SY) and Tartrazine (TA) over wide concentration ranges: 0.1-300 µM for MG (R2 = 0.994), 0.005-200 µM for SY (R2 = 0.996), and 0.005-300 µM for TA (R2 = 0.995) with low detection limits of 0.033 µM for MG, 0.0016 µM for SY, and 0.0016 µM for TA (S/N = 3), respectively. Additionally, the 3D CuFe2O4/Cu0@CFP sensor detected MG, SY, and TA in a mixed solution with satisfactory results. It also performs well in beverage, fruit juice powder, and jelly samples, with results matching those from HPLC.


Asunto(s)
Compuestos Azo , Cobre , Nanoestructuras , Colorantes de Rosanilina , Tartrazina , Cobre/química , Cobre/análisis , Tartrazina/análisis , Tartrazina/química , Nanoestructuras/química , Colorantes de Rosanilina/química , Colorantes de Rosanilina/análisis , Compuestos Azo/química , Compuestos Azo/análisis , Fibra de Carbono/química , Contaminación de Alimentos/análisis , Técnicas Electroquímicas/instrumentación , Límite de Detección , Colorantes de Alimentos/análisis , Colorantes de Alimentos/química , Papel
10.
J Biomol NMR ; 55(2): 147-55, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23344971

RESUMEN

One of the biggest challenges in solid-state NMR studies of membrane proteins is to obtain a homogeneous natively folded sample giving high spectral resolution sufficient for structural studies. Eukaryotic membrane proteins are especially difficult and expensive targets in this respect. Methylotrophic yeast Pichia pastoris is a reliable producer of eukaryotic membrane proteins for crystallography and a promising economical source of isotopically labeled proteins for NMR. We show that eukaryotic membrane protein human aquaporin 1 can be doubly ((13)C/(15)N) isotopically labeled in this system and functionally reconstituted into phospholipids, giving excellent resolution of solid-state magic angle spinning NMR spectra.


Asunto(s)
Acuaporina 1/química , Marcaje Isotópico/métodos , Pichia/genética , Acuaporina 1/genética , Isótopos de Carbono , Humanos , Liposomas , Isótopos de Nitrógeno , Resonancia Magnética Nuclear Biomolecular , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier
11.
Pharm Res ; 30(5): 1215-27, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23269504

RESUMEN

PURPOSE: Hyaluronic acid (HA)/polyethyleneimine-dexamethasone (PEI-Dex)/DNA ternary complexes with "core-shell" bilayer were developed for double level targeted gene delivery. A PEI1800-Dex, as a core, was applied to compact DNA into a nano-sized structure and facilitate the nuclear translocation of DNA after endocytosis into tumor cells, and a polyanion HA, as the outer corona, was employed to improve targeted tumor delivery and reduce cytotoxicity. METHODS: PEI-Dex was synthesized and characterized by (1)H NMR. The characterizations of ternary complexes were investigated. Their biological properties, including transfection efficiency, cytotoxicity, cellular uptake and in vivo efficacy were evaluated systemically. RESULTS: Ternary complexes with the size of about 160 nm exhibited the lowest cytotoxicity and the highest transfection efficiency in B16F10 cells among investigated complexes. The sub-cellular localization study confirmed that ternary complexes could facilitate more efficient cell uptake and nuclear transport of DNA than binary complexes. Moreover, Cy7-labeled ternary complexes obviously accumulated in the tumor after i.v. administration, indicating that ternary complexes could assist the DNA targeting to the tumor. In in vivo studies, HA/PEI1800-Dex/DNA ternary complexes showed confirmed anti-inflammation activity, and could significantly suppress tumor growth of tumor-bearing nude mice. CONCLUSIONS: HA/PEI-Dex/DNA ternary complexes might be a promising targeted gene delivery system.


Asunto(s)
Antiinflamatorios/administración & dosificación , ADN/administración & dosificación , Dexametasona/química , Ácido Hialurónico/química , Neoplasias Hepáticas/terapia , Polietileneimina/química , Transfección , Animales , Antiinflamatorios/uso terapéutico , Línea Celular Tumoral , ADN/uso terapéutico , Sistemas de Liberación de Medicamentos , Endocitosis , Células Hep G2 , Humanos , Hígado/efectos de los fármacos , Hígado/patología , Neoplasias Hepáticas/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos
12.
Can J Gastroenterol Hepatol ; 2022: 8169649, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36092537

RESUMEN

Methods: A total of 120 patients were randomized to receive either the control group (n = 64) or the experimental group (n = 65). Patients in the control group adopted the low-volume split-dose regimen one, and patients in the experimental group adopted the low-volume split-dose regimen two. Those randomized to regimen one were instructed to take 0.75 L PEG two hours after dinner the day before the colonoscopy and 1.5 L PEG 4 hours before the colonoscopy. Patients assigned to regimen two were invited to consume 1.5 L PEG two hours after dinner the day before the colonoscopy and 0.75 L PEG 4 hours before the colonoscopy. The quality of bowel preparation, rated according to a Boston Bowel Preparation Scale (BBPS), represented the primary outcome measure. Tolerability, satisfaction, and lesions detection rated were secondary outcomes. Results: There was no significant difference between the transverse colon and right colon scores between the two groups (P > 0.05). The low-volume split-dose regimen two showed a higher success rate for cleansing of the right colon and overall colon (P < 0.05). For the comparison of the patients' bowel tolerance, there were no statistical differences between the two groups regarding thirst, abdominal pain or abdominal discomfort, abdominal distension, dizziness or headache, anal discomfort, and sleep disturbance (P > 0.05). However, regimen two had significantly less nausea, vomiting, and fatigue than regimen one (24.62% vs. 42.19%, P=0.034; 10.77% vs. 25.00%, P=0.035; 6.15% vs. 21.88%, P=0.010, respectively). Patient-reported satisfaction and willingness to repeat the bowel preparation were significantly higher for low-volume split-dose regimen two than for low-volume split-dose regimen one (P=0.011; P=0.015). Conclusions: In early morning colonoscopies, the bowel-cleansing efficacy and patient tolerability of low-volume split-dose regimen two were superior to low-volume split-dose regimen one.


Asunto(s)
Catárticos , Polietilenglicoles , Catárticos/efectos adversos , Colonoscopía , Electrólitos , Humanos , Estudios Prospectivos
13.
Acta Biomater ; 103: 259-271, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31846803

RESUMEN

Multidrug resistance of cancer cells is one of the major obstacle for chemotherapeutic efficiency. Nitric oxide (NO) has raised the potential to overcome multidrug resistance (MDR) with low side effects. Herein, we report a reactive oxygen species (ROS) and glutathione (GSH) responsive nanoparticle for the delivery of NO prodrug such as S-nitrosoglutathione (GSNO), which was chemically conjugated to an amphiphilic block copolymer. The GSNO functionalized nanoparticles show high NO loading capacity, good stability and sustained NO release with specific GSH activated NO-releasing kinetics. Such GSNO functionalized nanoparticles delivered doxorubicin (DOX) in a ROS triggered manner and increased the intracellular accumulation of DOX. However, in normal healthy cells, showing physiological concentrations of ROS, these nanoparticles presented good biocompatibility. The present work indicated that these multifunctional nanoparticles can serve as effective co-delivery platforms of NO and DOX to selectively kill chemo-resistant cancer cells through increasing chemo-sensitivity. STATEMENT OF SIGNIFICANCE: In this work, we constructed nitric oxide donor (S-nitrosoglutathione, GSNO) functionalized amphiphilic copolymer (PEG-PPS-GSNO) to deliver doxorubicin (DOX). The developed PEG-PPS-GSNO@DOX nanoparticles presented high NO capacity, ROS triggered DOX release and GSH triggered NO release. Thus NO reversed the chemo-resistance in HepG2/ADR cells increasing intrcellular accumulation of DOX. Furthermore, these PEG-PPS-GSNO@DOX nanoparticles exhibited biocompatibility to healthy cells and toxicity to cancer cells, due to elevated ROS.


Asunto(s)
Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Polímeros/química , Especies Reactivas de Oxígeno/metabolismo , S-Nitrosoglutatión/farmacología , Muerte Celular/efectos de los fármacos , Doxorrubicina/farmacología , Liberación de Fármacos , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Endocitosis/efectos de los fármacos , Células HEK293 , Células Hep G2 , Humanos , Concentración 50 Inhibidora , Nanopartículas/ultraestructura , Neoplasias/patología , Óxido Nítrico , Tamaño de la Partícula , Polietilenglicoles/síntesis química , Polietilenglicoles/química , Polímeros/síntesis química , Espectroscopía de Protones por Resonancia Magnética , Sulfuros/síntesis química , Sulfuros/química
14.
Planta ; 229(6): 1231-42, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19277702

RESUMEN

We have previously isolated a Brassica juncea cDNA encoding a novel chitinase BjCHI1 with two chitin-binding domains (Zhao and Chye in Plant Mol Biol 40:1009-1018, 1999). The expression of BjCHI1 was highly inducible by methyl jasmonate (MeJA) treatment, wounding, caterpillar feeding, and pathogenic fungal infection. These observations suggest that the promoter of BjCHI1 gene might contain specific cis-acting elements for stress responses. Here, we report the cloning and characterization of the BjCHI1 promoter. A 1,098 bp BjCHI1 genomic DNA fragment upstream of the ATG start codon was isolated by PCR walking and various constructs were made by fusing the BjCHI1 promoter or its derivatives to beta-glucuronidase reporter gene. The transgenic Arabidopsis plants showed that the BjCHI1 promoter responded to wounding and MeJA treatment, and to treatments with either NaCl or polyethyleneglycol (PEG 6000), indicating that the BjCHI1 promoter responses to both biotic and abiotic stresses. A transient gene expression system of Nicotiana benthamiana leaves was adopted for promoter deletion analysis, and the results showed that a 76 bp region from -695 to -620 in the BjCHI1 promoter was necessary for MeJA-responsive expression. Furthermore, removal of a conserved T/G-box (AACGTG) at -353 to -348 of the promoter greatly reduced the induction by MeJA. This is the first T/G-box element identified in a chitinase gene promoter. Gain-of-function analysis demonstrated that the cis-acting element present in the 76 bp region requires coupling with the T/G-box to confer full magnitude of BjCHI1 induction by MeJA.


Asunto(s)
Brassica/genética , Quitinasas/genética , Proteínas de Plantas/genética , Regiones Promotoras Genéticas/genética , Acetatos/farmacología , Secuencia de Bases , Brassica/enzimología , Clonación Molecular , Ciclopentanos/farmacología , ADN de Plantas/química , ADN de Plantas/genética , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Glucuronidasa/genética , Glucuronidasa/metabolismo , Datos de Secuencia Molecular , Oxilipinas/farmacología , Reguladores del Crecimiento de las Plantas/farmacología , Polietilenglicoles/farmacología , Secuencias Reguladoras de Ácidos Nucleicos/genética , Elementos de Respuesta/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Cloruro de Sodio/farmacología , Estrés Mecánico , Sitio de Iniciación de la Transcripción
15.
Hepatobiliary Pancreat Dis Int ; 7(5): 529-32, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18842502

RESUMEN

BACKGROUND: The presence of bacteria in bile is an important factor in the formation of pigment gallstones. The bile of healthy people is sterile and bacteria in the biliary system come from endogenous infection from the gut. Yet, the route of bacterial translocation into the bile duct is still unclear. Theoretically, two routes exist: one is through the intestinal barrier and the other is by direct reflux from the sphincter of Oddi. This study was undertaken to explore the relationship between the effectiveness of intestinal barrier and the formation of pigment gallstones in hamsters. METHODS: Thirty-two hamsters were divided into an experimental and a control group, with 16 hamsters in each group. A low protein and high cellulose diet was given for 6 weeks to induce the formation of pigment gallstones in the experimental group (PS) and a normal diet was given to the control group (CON). Morphological changes, changes in the levels of serum endotoxin and diamine oxidase, and changes in the numbers of B lymphocytes, plasma cells and secretory immunoglobin A (sIgA) in the intestinal mucosa were assessed after 6 weeks. RESULTS: Four hamsters died during lithogenesis and body weight decreased in the PS group. Pigment gallstones were found in 11 hamsters at the end of the experiment, giving a lithogenesis rate of 91.67%. The serum endotoxin level before and after gallstone formation in the PS group was 0.2960+/-0.1734 U/ml and 8.2964+/-4.6268 U/ml, respectively (P<0.05). The blood diamine oxidase level before and after gallstone formation in the PS group was 2.6333+/-0.8037 U/ml and 3.3642+/-0.9545 U/ml, respectively (P<0.05). The numbers of B lymphocytes, plasma cells and sIgA in the intestinal mucosa in the PS group were 71.56+/-2.89, 68.65+/-2.09 and 27.56+/-1.07, respectively, and were significantly decreased compared with the corresponding values in the CON group (94.25+/-3.69, 93.47+/-3.98 and 42.57+/-1.96, respectively, P<0.05). CONCLUSIONS: A low protein and high cellulose diet can markedly reduce intestinal barrier function and facilitate the formation of pigment gallstones. The decrease of intestinal barrier function may take part in the formation of pigment gallstones.


Asunto(s)
Traslocación Bacteriana , Pigmentos Biliares/metabolismo , Bilis/microbiología , Cálculos Biliares/etiología , Mucosa Intestinal/microbiología , Amina Oxidasa (conteniendo Cobre)/sangre , Animales , Linfocitos B/inmunología , Linfocitos B/microbiología , Bilis/metabolismo , Celulosa , Cricetinae , Dieta con Restricción de Proteínas , Modelos Animales de Enfermedad , Endotoxinas/sangre , Femenino , Cálculos Biliares/inmunología , Cálculos Biliares/metabolismo , Cálculos Biliares/microbiología , Inmunoglobulina A Secretora/metabolismo , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Permeabilidad , Células Plasmáticas/inmunología , Células Plasmáticas/microbiología , Factores de Tiempo
16.
Environ Pollut ; 196: 47-52, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25299793

RESUMEN

Physiologically based in vitro methods have been developed to measure bioaccessibility of organic contaminants in soils. However, bioaccessibility of hydrophobic organic contaminants (HOCs) can be underestimated by in vitro tests if gastrointestinal (GI) solution fails to provide sufficient sorption sink for HOCs. To circumvent this drawback, Tenax was included in GI solution as sorption sink to trap mobilized HOCs and maintain the desorption gradient between soil and GI solution. Polycyclic aromatic hydrocarbons (PAHs) were selected as target HOCs, and physiologically based extraction test (PBET) was selected as the in vitro method. Inclusion of Tenax in GI solution increased bioaccessibility of PAHs in five spiked soils from 8.25-20.8% to 55.7-65.9% and the bioaccessibility of PAHs in a field contaminated soil from 3.70-6.92% to 16.3-31.0%. Our results demonstrated the effectiveness of Tenax as sorption sink to enhance PAH mobilization in bioaccessibility measurement in soils.


Asunto(s)
Monitoreo del Ambiente/métodos , Hidrocarburos Policíclicos Aromáticos/análisis , Polímeros/química , Contaminantes del Suelo/análisis , Absorción Fisicoquímica , Suelo/química
17.
BMJ Open ; 5(6): e007258, 2015 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-26038356

RESUMEN

OBJECTIVE: Randomised controlled trials (RCTs) have given contradictory results about the efficacy and safety of ibandronate in treating metastatic bone disease (MBD) or multiple myeloma. This review meta-analysed the literature to gain a more comprehensive picture. DESIGN: Systematic review and meta-analysis of ibandronate compared with placebo or zoledronate. DATA SOURCES: PubMed, EMBASE and the Cochrane Library databases were systematically searched to identify RCTs published up to March 2015 evaluating ibandronate to treat MBD or multiple myeloma. REVIEW METHOD: 10 RCTs involving 3474 patients were included. Six RCTs were placebo-controlled and four compared ibandronate with zoledronate. The studies included in this review were mainly from European countries. RESULTS: Intravenous ibandronate (6 mg) or oral drug (50 mg) decreased the risk of skeletal-related events compared to placebo (risk ratio (RR) 0.80, 95% CI 0.71 to 0.90, p=0.002). It also reduced the bone pain score below baseline significantly more than did placebo at 96 weeks (weighted mean difference -0.41, 95% CI -0.56 to -0.27, p<0.001). The incidence of diarrhoea, nausea and adverse renal events was similar between the ibandronate and placebo groups, but ibandronate was associated with greater risk of abdominal pain. Ibandronate was associated with similar risk of skeletal-related events as another bisphosphonate drug, zoledronate (RR 1.02, 95% CI 0.82 to 1.26, p=0.87). The incidence of nausea, jaw osteonecrosis and fatigue was similar for the two drugs, but the incidence of adverse renal events was significantly lower in the ibandronate group. CONCLUSIONS: Ibandronate significantly reduces the incidence of skeletal-related events and bone pain in patients with MBD or multiple myeloma relative to placebo. It is associated with a similar incidence of skeletal-related events as zoledronate.


Asunto(s)
Neoplasias Óseas/complicaciones , Resorción Ósea/tratamiento farmacológico , Difosfonatos/uso terapéutico , Mieloma Múltiple/complicaciones , Dolor Musculoesquelético/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Conservadores de la Densidad Ósea/uso terapéutico , Neoplasias Óseas/secundario , Resorción Ósea/etiología , Europa (Continente) , Humanos , Ácido Ibandrónico , Mieloma Múltiple/secundario , Dolor Musculoesquelético/etiología , Resultado del Tratamiento
18.
Environ Pollut ; 192: 113-20, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24907857

RESUMEN

We investigated effects of storage temperature and duration on release of antimony (Sb) and bisphenol A (BPA) from 16 brands of polyethylene terephthalate (PET) drinking water bottles in China. After 1-week storage, Sb release increased from 1.88-8.32 ng/L at 4 °C, to 2.10-18.4 ng/L at 25 °C and to 20.3-2604 ng/L at 70 °C. The corresponding releases for BPA were less at 0.26-18.7, 0.62-22.6, and 2.89-38.9 ng/L. Both Sb and BPA release increased with storage duration up to 4-week, but their releasing rates decreased with storage time, indicating that Sb and BPA release from PET bottles may become stable under long term storage. Human health risk was evaluated based on the worst case, i.e., storage at 70 °C for 4-week. Chronic daily intake (CDI) caused by BPA release was below USEPA regulation, Sb release in one brand exceeded USEPA regulated CDI (400 ng/kg bw/d) with values of 409 and 1430 ng/kg bw/d for adult and children.


Asunto(s)
Antimonio/análisis , Compuestos de Bencidrilo/análisis , Agua Potable/química , Exposición a Riesgos Ambientales/estadística & datos numéricos , Almacenamiento de Alimentos/métodos , Fenoles/análisis , Polietilenglicoles/química , Temperatura , Adulto , Antimonio/química , Compuestos de Bencidrilo/clasificación , Niño , China , Humanos , Fenoles/clasificación , Tereftalatos Polietilenos
19.
J Laparoendosc Adv Surg Tech A ; 23(4): 356-60, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23356209

RESUMEN

BACKGROUND/AIM: Single-incision laparoscopic fundoplication is not widespread because of its technical difficulty. An additional stay suture or retractor is often needed for liver retraction during the procedure. Here, we share our 7 cases to demonstrate the feasibility of transumbilical single-incision laparoscopic fundoplication with a new technique for liver retraction without any stay suture or retractor. PATIENTS AND METHODS: From March 2010 to October 2011, 3 patients with achalasia underwent a transumbilical single-incision laparoscopic Heller-Dor operation, and 4 patients with hiatus hernia underwent transumbilical single-incision laparoscopic hernioplasty and Nissen fundoplication. The procedures were attempted transumbilically by using three rigid trocars (one was 10 mm, and two were 5 mm) inserted through the 2-cm umbilicus incision. Conventional laparoscopic instruments were used. Adequate retraction of the liver was achieved by binding the lateral left lobe of the liver to the diaphragm with cyanoacrylate. RESULTS: The pneumoperitoneal time was 115-170 minutes, and blood loss was 15-50 mL. There were no intra- or postoperative complications. The hospital stay was under 6 days for all patients. The umbilical incision healed well with satisfactory cosmetic effect. CONCLUSIONS: The transumbilical single-incision laparoscopic technique in the treatment of achalaisa and hiatus hernia is feasible for an experienced laparoscope surgeon with excellent cosmetic effect. Cyanoacrylate, when used as described, offers a safe and simple solution to the problem of liver retraction, thus obviating the need for a stay suture or liver retractor.


Asunto(s)
Cianoacrilatos , Acalasia del Esófago/cirugía , Fundoplicación/métodos , Hernia Hiatal/cirugía , Laparoscopía/métodos , Adolescente , Adulto , Anciano , Estudios de Factibilidad , Femenino , Humanos , Hígado , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Ombligo
20.
J Mol Model ; 18(4): 1263-71, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21735123

RESUMEN

A type of shape memory polyurethane with 60 wt% hard segments (SMPU60) was prepared. Its material properties were tested by dynamic mechanical analysis (DMA) and Instron, and simulated using fully atomistic molecular dynamics (MD). The glass transition temperature (T (g)) of SMPU60 determined by DMA is 316 K, which is slightly lower than that estimated through MD simulations (T (g) = 328 K) , showing the calculated T ( g ) is in good agreement with experimental data. A complex hydrogen bonding network was revealed with the calculation of radial distribution functions (RDFs). The C═O⋯H bond is the predominant hydrogen-bonding interaction. With increasing temperature, both the hydrogen bonding and the moduli decreased, and the dissociation of intermolecular hydrogen bonding induced the decrease of the moduli.


Asunto(s)
Poliuretanos/química , Dureza , Enlace de Hidrógeno , Ensayo de Materiales , Modelos Moleculares , Simulación de Dinámica Molecular , Temperatura de Transición
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