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1.
Compend Contin Educ Dent ; 41(3): e1-e9, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32125165

RESUMEN

More than 2,000 dental implant options are estimated to be available for any given clinical situation. Because many implants have claims that are substantiated mainly on the basis of in vitro studies, it is prudent for clinicians to understand the interpretation of such studies and possible clinical relevance. In vitro tests can be segregated as surface analysis tests and mechanical assessment tests. With a wide variation of methodologies used and results achieved by different implant manufacturers, practitioners may find it difficult to judge the clinical significance of in vitro tests. This article provides an overview, including limitations, of the in vitro implant analysis tests implant companies routinely perform, ranging from older methods involving mechanical testing and surface microscopy to more recent tests such as atomic force microscopy (AFM) studies and gene expression tests, to assist clinicians when choosing an implant system. Having identified the limitations of in vitro testing methods, the current evidence indicates that scanning electron microscopy may be useful in providing insight on the role of implant surface topography. AFM, single cell tests, 3D imaging, and gene expression tests could be useful for assessment of cellular and physio-biochemical properties. 3D finite element analysis may help in the evaluation of mechanical properties of dental implants. Clinicians are encouraged to correlate the findings of in vitro tests with robust animal histologic studies and well-designed, high-quality clinical research to ascertain optimum clinical results.


Asunto(s)
Implantes Dentales , Animales , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Propiedades de Superficie , Titanio
2.
Environ Pollut ; 259: 113880, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32040986

RESUMEN

Silver nanoparticles (AgNP) are commonly used in medical, cosmetics, clothing, and industrial applications for their antibacterial and catalytic properties. As AgNP become more prevalent, the doses to which humans are exposed may increase and pose health risks, particularly through incidental inhalation. This exposure was evaluated through in-vitro methods simulating lung fluids and lung epithelium, and through computational fluid dynamics (CFD) methods of AgNP transport. A high-dose scenario simulated a short-term inhalation of 10 µg AgNP/m3, based on an exposure limit recommended by the National Institute of Occupational Safety and Health for the case of a health-care worker who handles AgNP-infused wound dressings, and regularly wears AgNP-imbedded clothing. Bioaccessibility tests were followed by a Parallel Artificial Membrane Permeability Assay (PAMPA) and supported by CFD models of the lung alveoli, membrane, pores, and blood capillaries. Results indicate that such exposure produces an average and maximum AgNP flux of approximately 4.7 × 10-21 and 6.5 × 10-19 mol m-2·s-1 through lung tissue, respectively, yielding a blood-silver accumulation of 0.46-64 mg per year, which may exceed the lowest adverse effect level of 25 mg for an adult male. Results from in-silico simulations were consistent with values estimated in vitro (within an order of magnitude), which suggest that CFD models may be used effectively to predict silver exposure from inhaled AgNP. Although the average short-term exposure concentrations are 3 orders of magnitude smaller than the reported threshold for mammalian cytotoxicity effects (observed at 5000 ppb), cumulative effects resulting from constant exposure to AgNP may pose risks to human health in the long-term, with predicted bioaccumulation reaching potential toxic effects after only five months of exposure, based on maximum flux.


Asunto(s)
Pulmón , Nanopartículas del Metal , Plata , Adulto , Antibacterianos , Simulación por Computador , Exposición a Riesgos Ambientales , Humanos , Hidrodinámica , Técnicas In Vitro , Pulmón/química , Pulmón/metabolismo , Masculino , Plata/metabolismo
3.
Toxicol Lett ; 325: 67-76, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32017982

RESUMEN

Racemic 3-quinuclidinyl-α-methoxydiphenylacetate (MB266) was synthesised. Its activity at muscarinic acetylcholine receptors (mAChRs), and muscle and neuronal nicotinic acetylcholine receptors (nAChRs), was compared to that of atropine and racemic 3-quinucidinyl benzilate (QNB) using a functional assay based on agonist-induced elevation of intracellular calcium ion concentration in CN21, Chinese Hamster Ovary (CHO) and SHSY5Y human cell lines. MB266 acted as an antagonist at acetylcholine receptors, displaying 18-fold selectivity for mAChR versus nAChR (compared to the 15,200-fold selectivity observed for QNB). Thus O-methylation of QNB reduced the affinity for mAChR antagonism and increased the relative potency at both muscle and neuronal nAChRs. Despite MB266 having a pharmacological profile potentially useful for the treatment of anticholinesterase poisoning, its administration did not improve the neuromuscular function in a soman-poisoned guinea-pig diaphragm preparation pretreated with the organophosphorus nerve agent soman. Consideration should be given to exploring the potential of MB266 for possible anticonvulsant action in vitro as part of a multi-targeted ligand approach.


Asunto(s)
Antídotos/farmacología , Antídotos/uso terapéutico , Inhibidores de la Colinesterasa/envenenamiento , Antagonistas Muscarínicos/farmacología , Antagonistas Muscarínicos/uso terapéutico , Agentes Nerviosos/envenenamiento , Antagonistas Nicotínicos/farmacología , Antagonistas Nicotínicos/uso terapéutico , Animales , Anticonvulsivantes/química , Anticonvulsivantes/uso terapéutico , Antídotos/síntesis química , Células CHO , Línea Celular , Cricetinae , Cricetulus , Diafragma/efectos de los fármacos , Cobayas , Humanos , Técnicas In Vitro , Masculino , Antagonistas Muscarínicos/síntesis química , Músculo Esquelético/efectos de los fármacos , Neuronas/efectos de los fármacos , Antagonistas Nicotínicos/síntesis química , Convulsiones/inducido químicamente , Convulsiones/prevención & control , Soman/envenenamiento
4.
Ultrasonics ; 103: 106095, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32044566

RESUMEN

We measured the apparent reflection coefficient of a 1-MHz ultrasound compressional wave at the interface between rough and lubricated tongue mimicking surfaces and various food gels, composed of agar or gelatin. For the smoothest mimicking surface, when a lubricating layer was present, the apparent reflection coefficient was fairly similar for the different food gels (33.6% on average). The apparent reflection coefficient was significantly larger in the following situations: (i) tongue asperities were high and dense; (ii) lubrication levels were low; and (iii) gels were less rigid (range for the different gels-45.9-84.3%). The apparent reflection coefficient conveys the ability of food gels to mold themselves to surface asperities or to form a coupling film of liquid at the interface. This study demonstrates that ultrasound methods can and should be used to explore the physical phenomena that underlie the texture perceptions resulting from tongue-palate interactions.


Asunto(s)
Alimentos , Lengua/diagnóstico por imagen , Ultrasonografía/métodos , Agar , Módulo de Elasticidad , Gelatina , Geles , Técnicas In Vitro , Lubrificación , Propiedades de Superficie
5.
Ultrasonics ; 103: 106097, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32078843

RESUMEN

Speed of Sound (SoS) maps from ultrasound tomography (UST) provide valuable quantitative information for soft tissue characterization and identification of lesions, making this technique interesting for breast cancer detection. However, due to the complexity of the processes that characterize the interaction of ultrasonic waves with matter, classic and fast tomographic algorithms such as back-projection are not suitable. Consequently, the image reconstruction process in UST is generally slow compared to other more conventional medical tomography modalities. With the aim of facilitating the translation of this technique into real clinical practice, several reconstruction algorithms are being proposed to make image reconstruction in UST to be a fast and accurate process. The geometrical acoustic approximation is often used to reconstruct SoS with less computational burden in comparison with full-wave inversion methods. In this work, we propose a simple formulation to perform on-the-flight reconstruction for UST using geometrical acoustics with refraction correction based on quadratic Bézier polynomials. Here we demonstrate that the trajectories created with these polynomials are an accurate approximation to reproduce the refracted acoustic paths connecting the emitter and receiver transducers. The method is faster than typical acquisition times in UST. Thus, it can be considered a step towards real-time reconstructions, which may contribute to its future clinical translation.


Asunto(s)
Procesamiento de Imagen Asistida por Computador/métodos , Ultrasonografía Mamaria , Algoritmos , Técnicas In Vitro , Modelos Estadísticos , Fantasmas de Imagen
6.
Allergol. immunopatol ; 48(1): 26-33, ene.-feb. 2020. ilus, graf
Artículo en Inglés | IBECS | ID: ibc-186588

RESUMEN

Introduction and Objectives: The production and consumption of oysters is increasing annually because it can provide essential nutrients and benefit for human health, leading to frequent occurrence of severe allergic reactions observed in sensitized individuals. The aim of the present study was to investigate the effects of acid and protease treatment on the conformation and IgE-binding capacity of recombinant Crassostrea gigas tropomyosin (Cra g 1). Results: Under acidic conditions, Cra g 1 did not undergo degradation, however, the changes obvious in the intensity of CD signal and ANS-binding fluorescence were observed, which was associated with a decrease in antibody reactivity. In simulated gastrointestinal fluid (SGF) and simulated intestinal fluid (SIF) digestion system, acid-treated Cra g 1 was relatively resistant to digestion, but the degradative patterns were very different. Moreover, owing to alterations of secondary structure and hydrophobic surface of the protein during digestive processing, antigenicity of acid-induced Cra g 1 reduced in SGF while it increased significantly in SIF. Conclusion: To our knowledge, this is the first study reporting that antigenicity of acid-treated oyster tropomyosin increased after SIF digestion. These results revealed that treatment with acid and pepsin, rather than trypsin, was an effective way of reducing IgE-binding capacity of tropomyosin from oyster


No disponible


Asunto(s)
Humanos , Inmunoglobulina E/inmunología , Técnicas In Vitro/métodos , Alérgenos/química , Tropomiosina/química , Hipersensibilidad a los Alimentos/inmunología , Digestión , Alérgenos/inmunología , Tropomiosina/inmunología , Ostreidae/inmunología , Sistema Digestivo/inmunología , Electroforesis/métodos , Análisis Espectral/métodos , Ensayo de Inmunoadsorción Enzimática
7.
Mikrobiyol Bul ; 54(1): 154-162, 2020 Jan.
Artículo en Turco | MEDLINE | ID: mdl-32050886

RESUMEN

Acinetobacter species lead to nosocomial infections in immunocompromised patients hospitalized in intensive care units or services. Acinetobacter baumannii is a bacterium that is difficult to treat because it is intrinsically resistant to many antibiotics and can develop resistance afterwards. This situation limits the use of existing antibiotics and directs the clinician to new agents, different treatment options and the use of various antibiotic combinations. The aim of this study was to determine the sensitivities of doripenem (DOR), tigecycline (TGC), minocycline (MIN), amikacin (AK) and a newly developed agent ceftolozane-tazobactam (CT) in multidrug resistant A.baumannii strains which were isolated from inpatients in intensive care units and to investigate the in vitro interactions of CT/DOR, CT/TGC, CT/MIN and CT/AK combinations by using antibiotic gradient test method. Thirty-five A.baumannii strains isolated from various clinical specimens (blood, urine, sputum, tracheal aspirate, wound, abscess and catheter) between January 2017 and July 2017 were included in the study. Strains isolated from inpatients in intensive care units and resistant to at least three antibiotic classes were selected. The identification of A.baumannii isolates and the determination of routine antibiotic susceptibility profile were performed according to EUCAST 2017 criteria by the use of BD Phoenix 100 (Becton Dickinson, USA) automated system. Minimum inhibitor concentration values of CT, DOR, TGC, MIN, AK and combinations of CT with four other antibiotics (CT/DOR, CT/TGC, CT/MIN and CT/AK) were determined by antibiotic gradient test method. Fractional inhibitor concentration index (FICI) was used to determine the interactions of the combinations in vitro. According to the data obtained; the FICI was evaluated as synergy if FICI ≤ 0.5, additive if 0.5 > FICI ≤ 1, indifferent (unidentified interaction) if 1

Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Cefalosporinas , Tazobactam , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/farmacología , Cefalosporinas/farmacología , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Sinergismo Farmacológico , Humanos , Técnicas In Vitro , Pruebas de Sensibilidad Microbiana , Tazobactam/farmacología
8.
Comput Biol Chem ; 84: 107191, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31901542

RESUMEN

Members of the let-7 family of miRNAs are well-known with their tumor suppressor properties as they are expressed at low levels in several types of human malignancies. Among them, let-7b and let-7c have gained special attention due their broad significance. Although the role of let-7b and let-7c have been widely reported in various types of cancers, their functional importance and role in oncogenic signaling of breast cancer is poorly investigated. Therefore, in the present study, prognostic and diagnostic significance of let-7b and let-7c in breast cancer and the effects these miRNAs on genes involved in cancer progression were determined by using several bioinformatics analysis and validated in vitro mimic assays, respectively. Using data of TCGA, OncomiR and dbDEMC 2.0, overall expression analysis of let-7b and let-7c was performed. The effect of let-7b and let-7c on genes involved in cancer progression was investigated by mimic transfection assays. We found that both let-7b and let-7c were significantly altered in breast cancer and associated with the clinicopathological findings of patients. Additionally, both let-7b and let-7c significantly altered oncogenic signaling in breast cancer cells. Consequently, both miRNAs might have fundamental roles in breast cancer progression and can be considered as potential targets for breast cancer therapy and diagnosis.


Asunto(s)
Neoplasias de la Mama/genética , Biología Computacional , MicroARNs/genética , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Técnicas In Vitro
9.
Plast Reconstr Surg ; 145(2): 409-418, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31985633

RESUMEN

BACKGROUND: Irradiated allogeneic costal cartilage is an alternative option of cartilage graft in patients with insufficient autologous cartilage. However, complications can occur during long-term follow-up. This study investigated whether Tutoplast-processed cartilage, one of the irradiated allogeneic costal cartilages, acts as a scaffold for adipose-derived stem cells and chondrogenesis. METHODS: In vitro setting, human adipose-derived stem cells seeded onto Tutoplast-processed cartilage were cultured in chondrogenic medium and observed using a scanning electron microscope. Next, 3 types of irradiated cartilage-including Tutoplast-processed cartilage, undifferentiated stem cells on Tutoplast-processed cartilage (undifferentiated group), and chondrogenic differentiated stem cells on Tutoplast-processed cartilage (chondrogenic group)-were implanted subcutaneously into nude mice. Gross, histologic, and gene expression analyses of Tutoplast-processed cartilages were performed at postoperative weeks 2 and 4. RESULTS: Human adipose-derived stem cells subjected to in vitro three-dimensional culture differentiated into chondrocytes and expressed cartilage-specificgenes. Adipose-derived stem cells seeded onto Tutoplast-processed cartilage were differentiated into chondrocytes in chondrogenic medium. In the chondrogenic group, the chondrogenic-differentiated cells attached to the surface of the Tutoplast-processed cartilage were maintained during the follow-up and were distinct from the existing Tutoplast-processed cartilage. Moreover, the chondrogenic group had higher expression of cartilage-specific genes compared with the undifferentiated group. CONCLUSIONS: Adipose-derived stem cells seeded onto Tutoplast-processed cartilage underwent chondrogenic differentiation, generating new cartilage, which was maintained after implantation without critical complications. The findings are clinically valuable in terms of overcoming the limitations of irradiated allogeneic costal cartilage, and broaden the surgical options for treatments requiring cartilage.


Asunto(s)
Cartílago/fisiología , Condrogénesis/fisiología , Células Madre Mesenquimatosas/fisiología , Agrecanos/metabolismo , Animales , Biomarcadores/metabolismo , Cartílago/efectos de la radiación , Diferenciación Celular/fisiología , Células Cultivadas , Colágeno Tipo X/metabolismo , Femenino , Humanos , Técnicas In Vitro , Inyecciones Subcutáneas , Músculos Intercostales , Trasplante de Células Madre Mesenquimatosas/métodos , Ratones Desnudos , Microscopía Electrónica de Rastreo , Persona de Mediana Edad , Modelos Animales , Reacción en Cadena en Tiempo Real de la Polimerasa , Trasplante Heterólogo , Trasplante Homólogo
10.
Toxicol Lett ; 322: 58-65, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31962155

RESUMEN

High-level concentrations of chlorine (Cl2) can cause life-threatening lung injuries and the objective in this study was to understand the pathogenesis of short-term sequelae of Cl2-induced lung injury and to evaluate whether pre-treatment with the antioxidant N-acetyl cysteine (NAC) could counteract these injuries using Cl2-exposed precision-cut lung slices (PCLS). The lungs of Sprague-Dawley rats were filled with agarose solution and cut into 250 µm-thick slices that were exposed to Cl2 (20-600 ppm) and incubated for 30 min. The tissue slices were pre-treated with NAC (5-25 mM) before exposure to Cl2. Toxicological responses were analyzed after 5 h by measurement of LDH, WST-1 and inflammatory mediators (IL-1ß, IL-6 and CINC-1) in medium or lung tissue homogenate. Exposure to Cl2 induced a concentration-dependent cytotoxicity (LDH/WST-1) and IL-1ß release in medium. Similar cytokine response was detected in tissue homogenate. Contraction of larger airways was measured using electric-field-stimulation method, 200 ppm and control slices had similar contraction level (39 ± 5%) but in the 400 ppm Cl2 group, the evoked contraction was smaller (7 ± 3%) possibly due to tissue damage. NAC-treatment improved cell viability and reduced tissue damage and the contraction was similar to control levels (50 ± 11%) in the NAC treated Cl2-exposed slices. In conclusion, Cl2 induced a concentration-dependent lung tissue damage that was effectively prevented with pre-treatment with NAC. There is a great need to improve the medical treatment of acute lung injury and this PCLS method offers a way to identify and to test new concepts of treatment of Cl2-induced lung injuries.


Asunto(s)
Acetilcisteína/farmacología , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Cloro/toxicidad , Mediadores de Inflamación/metabolismo , Lesión Pulmonar/prevención & control , Pulmón/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Quimiocina CXCL1/metabolismo , Citoprotección , Relación Dosis-Respuesta a Droga , Femenino , Técnicas In Vitro , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Pulmón/metabolismo , Pulmón/patología , Pulmón/fisiopatología , Lesión Pulmonar/inducido químicamente , Lesión Pulmonar/metabolismo , Lesión Pulmonar/patología , Ratas Sprague-Dawley
11.
Life Sci ; 244: 117343, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31978449

RESUMEN

AIMS: Epithelial-mesenchymal transition (EMT) is one of the important regulators of metastasis in advanced hepatocellular carcinoma (HCC). Blocking the Notch signaling pathway and then reversing the EMT process is a hot spot in clinical tumor research. Here, we aimed to investigate the effect and underlying mechanisms of ADAM-17 (a key cleavage enzyme of Notch pathway) inhibitor ZLDI-8 we found before on the metastasis of hepatocellular carcinoma in vitro and in vivo. MAIN METHODS: The cell viability of HCC cells was evaluated by MTT and colony formation assays. Migration and invasion were assessed respectively with wound healing and transwell assays. The expression and location of proteins were detected by western blot and immunofluorescence, respectively. The effects of ZLDI-8 on metastasis of liver cancer in vivo were investigated in a tail vein injection model. KEY FINDINGS: In the present work, ZLDI-8 significantly inhibited proliferation, migration, invasion and EMT phenotype of highly aggressive MHCC97-H and LM3 cells. Moreover, ZLDI-8 could inhibit the migration and invasion of HepG2 and Bel7402 cells induced by TGF-ß1. ZLDI-8 suppressed the protein expression of interstitial markers and increased that of epithelial markers. Meanwhile, ZLDI-8 decreased the expression of proteins in the Notch signaling pathway. Finally, ZLDI-8 blocks metastasis in the lung metastasis model in vivo. SIGNIFICANCE: ZLDI-8 suppressed the metastasis of hepatocellular carcinoma, which was associated with reversing the EMT process and regulating Notch signaling pathway. The study laid the foundation for the discovery of drugs that reverse EMT to inhibit advanced HCC metastasis.


Asunto(s)
Proteína ADAM17/antagonistas & inhibidores , Carcinoma Hepatocelular/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Animales , Apoptosis , Carcinoma Hepatocelular/enzimología , Carcinoma Hepatocelular/patología , Proliferación Celular , Humanos , Técnicas In Vitro , Neoplasias Hepáticas/enzimología , Neoplasias Hepáticas/patología , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/secundario , Ratones , Ratones Desnudos , Transducción de Señal , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Toxicol Lett ; 319: 237-241, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31738974

RESUMEN

The RSDL® (Reactive Skin Decontamination Lotion) Kit contains a lotion-impregnated sponge extensively studied for the removal or neutralization of chemical warfare agents from skin. Pilot investigation of efficacy with industrial threat compounds noted that synthetic opioid fentanyl citrate was removed by the RSDL Kit but not chemically inactivated by the lotion. This implies that after use the RSDL Kit will contain intact fentanyl, which may pose a dermal health hazard if the fentanyl is then transferred to skin after use without proper handling. This in vitro investigation studied the contaminated RSDL Kit using three different concentrations of fentanyl with a skin contact time of 15 min under direct interaction from passive contact, light touch, and leaning with one hand. It was demonstrated that the expected transfer of fentanyl from contaminated RSDL depends on 1) the concentration of fentanyl and 2) the area of the exposed surface. From a toxicological perspective, the contact risk of fentanyl under the conditions tested can be considered low but not absent. The present study determined that a contaminated RSDL Kit, used for removal of fentanyl, should be handled with proper care. Use of protective gloves in operational use and washing skin afterwards is advised to prevent undesired contamination.


Asunto(s)
Analgésicos Opioides/efectos adversos , Analgésicos Opioides/análisis , Contaminación de Medicamentos , Fentanilo/efectos adversos , Fentanilo/análisis , Crema para la Piel/efectos adversos , Crema para la Piel/análisis , Animales , Sustancias para la Guerra Química/química , Técnicas In Vitro , Proyectos Piloto , Medición de Riesgo , Absorción Cutánea , Porcinos
13.
J Endod ; 46(1): 103-109, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31761330

RESUMEN

INTRODUCTION: This in vitro study compared the performance of the XP-endo Shaper (XP; FKG, La Chaux-de-Fonds, Switzerland) in curved canals when used with a higher speed (3000 rpm) without a glide path with the manufacturer's protocol. METHODS: Twenty extracted mandibular molars with separate mesial curved canals were matched to obtain 2 standardized groups (n = 20). For the XP 1000 group, a glide path up to a size 15 hand file was performed followed by rotary instrumentation with the XP shaper at 1000 rpm, following the manufacturer's recommendations. For the canals in the XP 3000 group, the file was rotated at 3000 rpm after only negotiation the canal with a size 8 hand file (patency file). The operating time and the number of strokes taken to reach the working length (WL) and fit a 30/.04 gutta-percha cone to the WL were recorded. The shaping abilities were evaluated by micro-computed tomographic imaging and file deformation by scanning electron microscopy. Data were analyzed using analysis of variance and chi-square tests at a 5% significance level. RESULTS: The XP 3000 group required less time and strokes to reach the WL (P < .05) and resulted in a higher percentage of adequate cone fit (P < .05). No difference was found between groups regarding the micro-CT parameters, except for the taper, which was larger in the XP 3000 group in the apical and middle thirds (P < .05). No difference was found regarding file deformation between the 2 groups. CONCLUSIONS: The suggested protocol for the use of the XP (3000 rpm without a glide path) appears to be more efficient than the manufacturer's recommended protocol to prepare curved canals in vitro.


Asunto(s)
Cavidad Pulpar , Preparación del Conducto Radicular , Diseño de Equipo , Gutapercha , Técnicas In Vitro , Diente Molar
14.
Biosci Biotechnol Biochem ; 84(3): 621-632, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31762379

RESUMEN

The antioxidant activity of Petasites japonicus flower buds cultivated in Tokushima, Japan, was examined in vitro and in vivo. The flower bud extracts were assayed using either oxygen radical absorbance capacity or 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. Antioxidants in the 80% ethanol extract were investigated using online high-performance liquid chromatography-DPPH and were identified as caffeic acid, 3-O-caffeoylquinic acid, fukinolic acid, 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, and 4,5-di-O-caffeoylquinic acid using liquid chromatography-mass spectrometry. Fukinolic acid was the most active compound based on its activity and abundance. Administering the extracts orally to ICR mice prior to iron injection significantly suppressed plasma thiobarbituric acid reactive substance (TBARS) production. Moreover, TBARS and triglyceride concentrations in the plasma of C57BL/6 mice fed with a high fat diet were also significantly decreased by the extract. The results suggest that antioxidative compounds in P. japonicus can be used in the management of oxidative stress.


Asunto(s)
Antioxidantes/farmacología , Flores/química , Petasites/química , Extractos Vegetales/farmacología , Animales , Cromatografía Líquida de Alta Presión/métodos , Técnicas In Vitro , Masculino , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Estrés Oxidativo/efectos de los fármacos , Espectrometría de Masas en Tándem , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
15.
Food Chem Toxicol ; 135: 110985, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31765700

RESUMEN

Investigation of antiviral and cytotoxic effect of quercetin 3-glucoside (Q3G) from Dianthus superbus L over influenza virus infection and replication were studied. Moreover, anti-influenza mechanism was screened by time-dependent antiviral assay, virus-induced symptoms and related gene expressions. The blockade of cap-binding domain of polymerase basic protein subunit were analysed by molecular docking study. The Q3G demonstrated potent antiviral activity showing 4.93, 6.43, 9.94, 8.3, and 7.1 µg/mL of IC50 for A/PR/8/34, A/Victoria/3/75, A/WS/33, B/Maryland/1/59, and B/Lee/40, respectively. The cellular toxicity of Q3G and oseltamivir (control) were tested and >100 µg/mL of CC50 value considered as nontoxic. Influenza A virus infection induced a higher ROS production, however potentially reduced by Q3G treatment and significantly blocked virus infection induced acidic vesicular organelles (AVO). Moreover, Q3G has no inhibitory effect for neuraminidase activity but blocked virus replication through time dependent assay and showed more competitive binding affinity (-8.0 kcal/mal) than GTP (-7.0 kcal/mol) to block polymerase basic protein-2 subunit of influenza virus. Q3G from D. superbus showed potent antiviral activity against influenza A and B viruses with suppressive effect on virus-induced cellular ROS generation and AVO formation. Thus, this study provided a new line of research for Q3G to develop possible natural anti-influenza drug.


Asunto(s)
Antivirales/farmacología , Dianthus/química , Virus de la Influenza A/efectos de los fármacos , Virus de la Influenza B/efectos de los fármacos , Gripe Humana/tratamiento farmacológico , Quercetina/análogos & derivados , Animales , Antivirales/toxicidad , Supervivencia Celular/efectos de los fármacos , Simulación por Computador , Perros , Humanos , Técnicas In Vitro , Virus de la Influenza A/genética , Virus de la Influenza A/fisiología , Virus de la Influenza B/genética , Virus de la Influenza B/fisiología , Gripe Humana/virología , Células de Riñón Canino Madin Darby , Simulación del Acoplamiento Molecular , Quercetina/farmacología , Quercetina/toxicidad , ARN Viral/biosíntesis , Especies Reactivas de Oxígeno/metabolismo , Replicación Viral/efectos de los fármacos
16.
J Appl Oral Sci ; 28: e20190042, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31778443

RESUMEN

INTRODUCTION: Gap formation of composite resin restorations is a serious shortcoming in clinical practice. Polymerization shrinkage stress exceeds the tooth-restoration bond strength, and it causes bacterial infiltration within gaps between cavity walls and the restorative material. Thus, an intermediate liner application with a low elastic modulus has been advised to minimize polymerization shrinkage as well as gap formation. OBJECTIVE: The purpose of this in vitro study was to assess gap formation volume in premolars restored with different bulk-fill composites, with and without a resin-modified glass-ionomer cement (RMGIC) liner, using x-ray micro-computed tomography (micro-CT). METHODOLOGY: Sixty extracted human maxillary premolars were divided into six groups according to bucco-palatal dimensions (n=10). Standardized Class II mesio-occluso-distal cavities were prepared. G-Premio Bond (GC Corp., Japan) was applied in the selective-etch mode. Teeth were restored with high-viscosity (Filtek Bulk Fill, 3M ESPE, USA)-FB, sonic-activated (SonicFill 2, Kerr, USA)-SF and low viscosity (Estelite Bulk Fill Flow, Tokuyama, Japan)-EB bulk-fill composites, with and without a liner (Ionoseal, Voco GmbH, Germany)-L. The specimens were subjected to 10,000 thermocycles (5-55°C) and 50,000 simulated chewing cycles (100 N). Gap formation based on the volume of black spaces at the tooth-restoration interface was quantified in mm3 using micro-computed tomography (SkyScan, Belgium), and analyses were performed. Data were analyzed using repeated-measures ANOVA and the Bonferroni correction test (p < 0.05). RESULTS: The gap volume of all tested bulk-fill composites demonstrated that Group SF (1.581±0.773) had significantly higher values than Group EB (0.717±0.679). Regarding the use of a liner, a significant reduction in gap formation volume was observed only in Group SFL (0.927±0.630) compared with Group SF (1.581±0.773). CONCLUSION: It can be concluded that different types of bulk-fill composite resins affected gap formation volume. Low-viscosity bulk-fill composites exhibited better adaptation to cavity walls and less gap formation than did sonic-activated bulk-fill composites. The use of an RMGIC liner produced a significant reduction in gap formation volume for sonic-activated bulk-fill composites.


Asunto(s)
Resinas Compuestas/química , Preparación de la Cavidad Dental/métodos , Materiales Dentales/química , Restauración Dental Permanente/métodos , Imagen Tridimensional/métodos , Polimerizacion , Análisis del Estrés Dental , Humanos , Técnicas In Vitro , Ensayo de Materiales , Cementos de Resina , Microtomografía por Rayos X
17.
World Neurosurg ; 133: e739-e744, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31606499

RESUMEN

OBJECTIVE: To carry out surgery safely in vessels with stents, it is essential to have knowledge of what would happen if the stents were clamped or cut. Using all stents that are permitted in Japan, we recorded with a surgical microscope the behavior of stents when they were clamped or cut and discussed the morphologic changes along with image findings. METHODS: We classified carotid artery and intracranial stents as group 1A and 1B or group 2A and 2B according to the structure of stent eye: laser cut or blade. Each stent was clamped using a Yasargil aneurysm clip, bulldog forceps, and vascular forceps. Degree of closure and presence or absence of stent deformation after declamping were recorded using a surgical microscope. Furthermore, we performed morphologic evaluations using high-resolution cone-beam computed tomography. Lastly, each stent was cut; the behavior of the cut stent was recorded, and differences between stents were examined. RESULTS: Complete clamping was confirmed both visually and based on image evaluations with bulldog forceps and vascular forceps in the groups of carotid artery stents, with the Yasargil aneurysm clip in the intracranial stents. In the blade-type stents, we found that the stents elongated during clamping, and the component wire scattered at the time of stent cutting. Furthermore, the stents could be easily separated by holding with forceps. CONCLUSIONS: Knowing the properties of each stent is essential to conduct safe surgery in response to complications. Special care must be taken when clamping and cutting blade-type stents.


Asunto(s)
Procedimientos Endovasculares/instrumentación , Ensayo de Materiales , Stents , Arterias Carótidas/cirugía , Humanos , Técnicas In Vitro , Aneurisma Intracraneal/cirugía
18.
Food Chem Toxicol ; 135: 110888, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31629789

RESUMEN

Glyphosate is used for cereal, vegetable and fruit crops for reducing or inhibiting the growth of weeds as well as a desiccant for various grain crops. That is why, glyphosate has been shown to be accumulated in humans and animals through ingestion of food of both plant and animal origin. The study aimed to assessed the effect of glyphosate, its metabolites: aminomethylphosphonic acid (AMPA), methylphosphonic acid and its impurities: PMIDA, N-methylglyphosate, hydroxymethylphosphonic acid and bis(phosphonomethyl)amine on apoptosis induction in human peripheral blood mononuclear cells (PBMCs). PBMCs were exposed to the compounds studied at the concentrations ranging from 0.01 to 5 mM for 4 h. We have observed an increase in reactive oxygen species (including hydroxyl radical) and cytosolic calcium ions levels as well as reduction of transmembrane mitochondrial potential (ΔΨm) in PBMCs exposed to the compounds examined. All substances studied changed PBMCs membrane permeability, activated caspase-8, -9, -3 and caused chromatin condensation, which showed that they were capable of inducing apoptosis both via extrinsic and particularly intrinsic pathway. Generally the study demonstrated that there were no differences between apoptotic changes induced by glyphosate, its metabolites or impurities, and observed changes were provoked by high concentrations of investigated compounds.


Asunto(s)
Apoptosis/efectos de los fármacos , Glicina/análogos & derivados , Herbicidas/toxicidad , Monocitos/efectos de los fármacos , Calcio/sangre , Caspasas/metabolismo , Cromatina/metabolismo , Activación Enzimática , Glicina/metabolismo , Glicina/toxicidad , Herbicidas/metabolismo , Humanos , Radical Hidroxilo/metabolismo , Técnicas In Vitro , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Monocitos/metabolismo , Especies Reactivas de Oxígeno/metabolismo
19.
Life Sci ; 240: 117068, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31751583

RESUMEN

AIMS: Bradycardia contributes to tachy-brady arrhythmias or sinus arrest during heart failure (HF). Sinoatrial node (SAN) adenosine A1 receptors (ADO A1Rs) are upregulated in HF, and adenosine is known to exert negative chronotropic effects on the SAN. Here, we investigated the role of A1R signaling at physiologically relevant ADO concentrations on HF SAN pacemaker cells. MAIN METHODS: Dogs with tachypacing-induced chronic HF and normal controls (CTL) were studied. SAN tissue was collected for A1R and GIRK mRNA quantification. SAN cells were isolated for perforated patch clamp recordings and firing rate (bpm), slope of slow diastolic depolarization (SDD), and maximum diastolic potential (MDP) were measured. Action potentials (APs) and currents were recorded before and after addition of 1 and 10 µM ADO. To assess contributions of A1R and G protein-coupled Inward Rectifier Potassium Current (GIRK) to ADO effects, APs were measured after the addition of DPCPX (selective A1R antagonist) or TPQ (selective GIRK blocker). KEY FINDINGS: A1R and GIRK mRNA expression were significantly increased in HF. In addition, ADO induced greater rate slowing and membrane hyperpolarization in HF vs CTL (p < 0.05). DPCPX prevented ADO-induced rate slowing in CTL and HF cells. The ADO-induced inward rectifying current, IKado, was observed significantly more frequently in HF than in CTL. TPQ prevented ADO-induced rate slowing in HF. SIGNIFICANCE: An increase in A1R and GIRK expression enhances IKAdo, causing hyperpolarization, and subsequent negative chronotropic effects in canine chronic HF at relevant [ADO]. GIRK blockade may be a useful strategy to mitigate bradycardia in HF.


Asunto(s)
Agonistas del Receptor de Adenosina A1/farmacología , Adenosina/farmacología , Canales de Potasio Rectificados Internamente Asociados a la Proteína G/agonistas , Insuficiencia Cardíaca/fisiopatología , Frecuencia Cardíaca/efectos de los fármacos , Receptor de Adenosina A1/metabolismo , Nodo Sinoatrial/citología , Nodo Sinoatrial/efectos de los fármacos , Potenciales de Acción/efectos de los fármacos , Antagonistas del Receptor de Adenosina A1/farmacología , Animales , Venenos de Abeja/farmacología , Relojes Biológicos , Enfermedad Crónica , Perros , Femenino , Canales de Potasio Rectificados Internamente Asociados a la Proteína G/antagonistas & inhibidores , Canales de Potasio Rectificados Internamente Asociados a la Proteína G/efectos de los fármacos , Técnicas In Vitro , Masculino , Técnicas de Placa-Clamp , Bloqueadores de los Canales de Potasio/farmacología , Receptor de Adenosina A1/efectos de los fármacos , Xantinas/farmacología
20.
Br J Radiol ; 93(1106): 20190702, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31825653

RESUMEN

OBJECTIVE: Recent in vivo results have shown prominent tissue sparing effect of radiotherapy with ultra-high dose rates (FLASH) compared to conventional dose rates (CONV). Oxygen depletion has been proposed as the underlying mechanism, but in vitro data to support this have been lacking. The aim of the current study was to compare FLASH to CONV irradiation under different oxygen concentrations in vitro. METHODS: Prostate cancer cells were irradiated at different oxygen concentrations (relative partial pressure ranging between 1.6 and 20%) with a 10 MeV electron beam at a dose rate of either 600 Gy/s (FLASH) or 14 Gy/min (CONV), using a modified clinical linear accelerator. We evaluated the surviving fraction of cells using clonogenic assays after irradiation with doses ranging from 0 to 25 Gy. RESULTS: Under normoxic conditions, no differences between FLASH and CONV irradiation were found. For hypoxic cells (1.6%), the radiation response was similar up to a dose of about 5-10 Gy, above which increased survival was shown for FLASH compared to CONV irradiation. The increased survival was shown to be significant at 18 Gy, and the effect was shown to depend on oxygen concentration. CONCLUSION: The in vitro FLASH effect depends on oxygen concentration. Further studies to characterize and optimize the use of FLASH in order to widen the therapeutic window are indicated. ADVANCES IN KNOWLEDGE: This paper shows in vitro evidence for the role of oxygen concentration underlying the difference between FLASH and CONV irradiation.


Asunto(s)
Oxígeno , Neoplasias de la Próstata/radioterapia , Supervivencia Celular/efectos de la radiación , Humanos , Técnicas In Vitro , Masculino , Dosificación Radioterapéutica , Células Tumorales Cultivadas , Hipoxia Tumoral/efectos de la radiación , Ensayo de Tumor de Célula Madre
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