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1.
J Endocrinol Invest ; 44(11): 2375-2386, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33646556

RESUMEN

BACKGROUND: This study aimed to identify the potential circulating biomarkers of protein, mRNAs, and long non-coding RNAs (lncRNAs) to differentiate the papillary thyroid cancers from benign thyroid tumors. METHODS: The study population of 100 patients was classified into identification (10 patients with papillary thyroid cancers and 10 patients with benign thyroid tumors) and validation groups (45 patients with papillary thyroid cancers and 35 patients with benign thyroid tumors). The Sengenics Immunome Protein Array-combined data mining approach using the Open Targets Platform was used to identify the putative protein biomarkers, and their expression validated using the enzyme-linked immunosorbent assay. Next-generation sequencing by Illumina HiSeq was used for the detection of dysregulated mRNAs and lncRNAs. The website Timer v2.0 helped identify the putative mRNA biomarkers, which were significantly over-expressed in papillary thyroid cancers than in adjacent normal thyroid tissue. The mRNA and lncRNA biomarker expression was validated by a real-time polymerase chain reaction. RESULTS: Although putative protein and mRNA biomarkers have been identified, their serum expression could not be confirmed in the validation cohorts. In addition, seven lncRNAs (TCONS_00516490, TCONS_00336559, TCONS_00311568, TCONS_00321917, TCONS_00336522, TCONS_00282483, and TCONS_00494326) were identified and validated as significantly downregulated in patients with papillary thyroid cancers compared to those with benign thyroid tumors. These seven lncRNAs showed moderate accuracy based on the area under the curve (AUC = 0.736) of receiver operating characteristic in predicting the occurrence of papillary thyroid cancers. CONCLUSIONS: We identified seven downregulated circulating lncRNAs with the potential for predicting the occurrence of papillary thyroid cancers.


Asunto(s)
Proteínas de Neoplasias , Neoplasias , ARN Largo no Codificante/sangre , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides , Área Bajo la Curva , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/clasificación , Ácidos Nucleicos Libres de Células/sangre , Diagnóstico Diferencial , Regulación hacia Abajo , Femenino , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/sangre , Proteínas de Neoplasias/clasificación , Neoplasias/sangre , Neoplasias/diagnóstico , Valor Predictivo de las Pruebas , Cáncer Papilar Tiroideo/sangre , Cáncer Papilar Tiroideo/diagnóstico , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/diagnóstico
2.
J Synchrotron Radiat ; 27(Pt 1): 158-163, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31868748

RESUMEN

Advanced imaging is useful for understanding the three-dimensional (3D) growth of cells. X-ray tomography serves as a powerful noninvasive, nondestructive technique that can fulfill these purposes by providing information about cell growth within 3D platforms. There are a limited number of studies taking advantage of synchrotron X-rays, which provides a large field of view and suitable resolution to image cells within specific biomaterials. In this study, X-ray synchrotron radiation microtomography at Diamond Light Source and advanced image processing were used to investigate cellular infiltration of HeLa cells within poly L-lactide (PLLA) scaffolds. This study demonstrates that synchrotron X-rays using phase contrast is a useful method to understand the 3D growth of cells in PLLA electrospun scaffolds. Two different fiber diameter (2 and 4 µm) scaffolds with different pore sizes, grown over 2, 5 and 8 days in vitro, were examined for infiltration and cell connectivity. After performing visualization by segmentation of the cells from the fibers, the results clearly show deeper cell growth and higher cellular interconnectivity in the 4 µm fiber diameter scaffold. This indicates the potential for using such 3D technology to study cell-scaffold interactions for future medical use.


Asunto(s)
Células HeLa/ultraestructura , Andamios del Tejido , Microtomografía por Rayos X/métodos , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Poliésteres , Porosidad , Sincrotrones
3.
Phys Chem Chem Phys ; 19(33): 22111-22120, 2017 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-28795708

RESUMEN

The growth of electrodeposited lithium microstructures on metallic lithium electrodes has prevented their use in rechargeable lithium batteries due to early performance degradation and safety implications. Understanding the evolution of lithium microstructures during battery operation is crucial for the development of an effective and safe rechargeable lithium-metal battery. This study employs both synchrotron and laboratory X-ray computed tomography to investigate the morphological evolution of the surface of metallic lithium electrodes during a single cell discharge and over numerous cycles, respectively. The formation of surface pits and the growth of mossy lithium deposits through the separator layer are characterised in three-dimensions. This has provided insight into the microstructural evolution of lithium-metal electrodes during rechargeable battery operation, and further understanding of the importance of separator architecture in mitigating lithium dendrite growth.

4.
J Synchrotron Radiat ; 22(2): 336-41, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25723934

RESUMEN

Hard X-ray microscopy is a prominent tool suitable for nanoscale-resolution non-destructive imaging of various materials used in different areas of science and technology. With an ongoing effort to push the 2D/3D imaging resolution down to 10 nm in the hard X-ray regime, both the fabrication of nano-focusing optics and the stability of the microscope using those optics become extremely challenging. In this work a microscopy system designed and constructed to accommodate multilayer Laue lenses as nanofocusing optics is presented. The developed apparatus has been thoroughly characterized in terms of resolution and stability followed by imaging experiments at a synchrotron facility. Drift rates of ∼2 nm h(-1) accompanied by 13 nm × 33 nm imaging resolution at 11.8 keV are reported.

5.
Phys Rev Lett ; 110(13): 138105, 2013 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-23581380

RESUMEN

We present a new quantitative x-ray phase-contrast imaging method based on the edge illumination principle, which allows achieving unprecedented nanoradian sensitivity. The extremely high angular resolution is demonstrated theoretically and through experimental images obtained at two different synchrotron radiation facilities. The results, achieved at both very high and very low x-ray energies, show that this highly sensitive technique can be efficiently exploited over a very broad range of experimental conditions. This method can open the way to new, previously inaccessible scientific applications in various fields including biology, medicine and materials science.


Asunto(s)
Modelos Teóricos , Tomografía Computarizada por Rayos X/instrumentación , Tomografía Computarizada por Rayos X/métodos , Polipropilenos/química
6.
Sci Rep ; 10(1): 10366, 2020 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-32587288

RESUMEN

To travel safely behind screens that can protect us from stones and hail, we must understand the response of glass to impact. However, without a means to observe the mechanisms that fail different silicate architectures, engineering has relied on external sensors, post-impact examination and best-guess to glaze our vehicles. We have used single and multi-bunch, X-ray imaging to differentiate distinct phases of failure in two silicates. We identified distinct micromechanisms, operating in tandem and leading to failure in borosilicate glass and Z-cut quartz. A surface zone in the amorphous glass densifies before bulk fracture occurs and then fails the block, whilst in quartz, fast cracks, driven down cleavage planes, fails the bulk. Varying the rate at which ejecta escapes by using different indenter tip geometries controls the failed target's bulk strength. This opens the way to more physically based constitutive descriptions for the glasses allowing design of safer, composite panels by controlling the impulses felt by protective screens.

7.
Rev Esp Med Nucl ; 28(6): 278-82, 2009.
Artículo en Español | MEDLINE | ID: mdl-19995534

RESUMEN

UNLABELLED: Coronary artery disease (CAD) is the leading cause of death in many countries. Stress electrocardiogram (ECG) is able to detect myocardial ischemia and also has prognostic value, which may be impaired in presence of electrical baseline abnormalities. Stress myocardial single photon emission tomography (SPECT) has recognized utility yield in assessment of CAD, requiring independent interpretation of ECG and myocardial images. PURPOSE: To analyze stress ECG interpretation reproducibility among observers with different training level, including pre- and post-graduate medical students, compared to an experienced cardiologist and also with SPECT. METHOD: We studied 95 patients under CAD evaluation, mean age 61+/-9.3 years (range: 42-85), 56% male. Interobserver correlation kappa (k) between perfusion gated (99m)Tc-Sestamibi SPECT and exercise ECG were calculated as normal/abnormal, presence of necrosis, ischemia or mixed pattern. Interobserver kappa (k) analysis was made. RESULTS: 49.5% stress ECG and 45% SPECT studies were abnormal at the initial report with 62.1% concordance (k: 0.24) for normal/abnormal and 58.9% for ischemia (k: 0.14). Agreement between stress ECG initial report and independent cardiologist was 89.5% (k: 0.78). The correlation between independent observers and the initial report ranged between 62.1% and 48.4%, for baseline ECG between 41.1% and 90.5% considering normal/abnormal, and between 80% and 93.7% (k: 0.59-0.87) for the presence of ischemia. CONCLUSION: Stress ECG interpretation presented adequate interobserver reproducibility with greater agreement in the most experienced observers, confirming the importance of training.


Asunto(s)
Enfermedad Coronaria/diagnóstico por imagen , Prueba de Esfuerzo , Imagen de Perfusión Miocárdica , Variaciones Dependientes del Observador , Tomografía Computarizada de Emisión de Fotón Único , Adulto , Anciano , Anciano de 80 o más Años , Cardiología/educación , Competencia Clínica , Electrocardiografía , Femenino , Imagen de Acumulación Sanguínea de Compuerta , Humanos , Masculino , Persona de Mediana Edad , Medicina Nuclear/educación , Médicos/psicología , Reproducibilidad de los Resultados , Método Simple Ciego , Estudiantes de Medicina/psicología
8.
Orthopade ; 37(2): 102-10, 2008 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-18210091

RESUMEN

The object of the present study was to determine the incidence of metal sensitivity in patients with joint replacement arthroplasties before and after surgery and whether this is of significance as regards the final outcome of the operative procedure. A questionnaire-based survey involved 1,335 patients with an average age of 61 years and joint replacement arthroplasties before and after surgery. A history of dermal sensitivity to metal was given in 99 (7%) patients with almost equal frequency in the pre- and postoperative groups (7.6 vs 7.2%). In only 27 of 99 cases was the metal sensitivity recorded in the patient chart. In 46 cases investigation was done after knee or hip replacement arthroplasty with an average implant time in situ of 68 months. In 32 of 46 patients a sensitivity to the implanted material was known and they did not show any complications related to the metal sensitivity.It is currently unclear whether metal sensitivity could be induced by joint replacement arthroplasties and it remains uncertain whether loosening or infection causes the sensitization as a consequence of increased release of metal ions or vice versa. To draw further conclusions considerably more detailed studies involving more patients are clearly indicated.


Asunto(s)
Cobalto/efectos adversos , Prótesis de Cadera/efectos adversos , Hipersensibilidad/epidemiología , Prótesis de la Rodilla/efectos adversos , Níquel/efectos adversos , Complicaciones Posoperatorias/epidemiología , Adulto , Anciano , Estudios Transversales , Dermatitis Alérgica por Contacto/diagnóstico , Dermatitis Alérgica por Contacto/epidemiología , Femenino , Estudios de Seguimiento , Alemania , Humanos , Hipersensibilidad/diagnóstico , Incidencia , Masculino , Persona de Mediana Edad , Pruebas del Parche , Complicaciones Posoperatorias/diagnóstico , Falla de Prótesis , Factores de Riesgo , Encuestas y Cuestionarios
9.
Proc Math Phys Eng Sci ; 473(2197): 20160495, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28265185

RESUMEN

The well-known Taylor cylinder impact test, which follows the impact of a flat-ended cylindrical rod onto a rigid stationary anvil, is conducted over a range of impact speeds for two polymers, polytetrafluoroethylene (PTFE) and polyetheretherketone (PEEK). In previous work, experiments and a model were developed to capture the deformation behaviour of the cylinder after impact. These works showed a region in which spatial and temporal variation of both longitudinal and radial deformation provided evidence of changes in phase within the material. In this further series of experiments, this region is imaged in a range of impacted targets at the Diamond synchrotron. Further techniques were fielded to resolve compressed regions within the recovered polymer cylinders that showed a fracture zone in the impact region. The combination of macroscopic high-speed photography and three-dimensional X-ray imaging has identified the development of failure with these polymers and shown that there is no abrupt transition in behaviours but rather a continuous range of responses to competing operating mechanisms. The behaviours noted in PEEK in these polymers show critical gaps in understanding of polymer high strain-rate response.

10.
Oncogene ; 36(38): 5440, 2017 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-28714961

RESUMEN

This corrects the article DOI: 10.1038/onc.2014.43.

11.
Microsc Res Tech ; 69(8): 660-5, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16788978

RESUMEN

This paper concerns an important aspect of current developments in medical and biological imaging: the possibility for imaging soft tissue at relatively high resolution in the micrometer range or better, without tedious and/or entirely destructive sample preparation. Structures with low absorption contrast have been visualized using in-line phase contrast imaging. The experiments have been performed at the Advanced Photon Source, a third generation source of synchrotron radiation. The source provides highly coherent X-ray radiation with high photon flux (>10(14) photons/s) at high photon energies (5-70 keV). Thick gerbil cochlear slices have been imaged and were compared with those obtained by light microscopy. Furthermore, intact gerbil cochleae have been imaged to identify the soft tissue structures involved in the hearing process. The present experimental approach was essential for visualizing the inner ear structures involved in the hearing process in an intact cochlea.


Asunto(s)
Cóclea/diagnóstico por imagen , Microscopía/métodos , Rayos X , Animales , Cóclea/anatomía & histología , Cóclea/citología , Gerbillinae , Modelos Anatómicos , Intensificación de Imagen Radiográfica/instrumentación , Intensificación de Imagen Radiográfica/métodos , Sincrotrones/instrumentación
12.
Rev Sci Instrum ; 87(9): 093505, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27782568

RESUMEN

New complex-plasma facility, Plasmakristall-4 (PK-4), has been recently commissioned on board the International Space Station. In complex plasmas, the subsystem of µm-sized microparticles immersed in low-pressure weakly ionized gas-discharge plasmas becomes strongly coupled due to the high (103-104 e) electric charge on the microparticle surface. The microparticle subsystem of complex plasmas is available for the observation at the kinetic level, which makes complex plasmas appropriate for particle-resolved modeling of classical condensed matter phenomena. The main purpose of PK-4 is the investigation of flowing complex plasmas. To generate plasma, PK-4 makes use of a classical dc discharge in a glass tube, whose polarity can be switched with the frequency of the order of 100 Hz. This frequency is high enough not to be felt by the relatively heavy microparticles. The duty cycle of the polarity switching can be also varied allowing to vary the drift velocity of the microparticles and (when necessary) to trap them. The facility is equipped with two videocameras and illumination laser for the microparticle imaging, kaleidoscopic plasma glow observation system and minispectrometer for plasma diagnostics and various microparticle manipulation devices (e.g., powerful manipulation laser). Scientific experiments are programmed in the form of scripts written with the help of specially developed C scripting language libraries. PK-4 is mainly operated from the ground (control center CADMOS in Toulouse, France) with the support of the space station crew. Data recorded during the experiments are later on delivered to the ground on the removable hard disk drives and distributed to participating scientists for the detailed analysis.

13.
Oncogene ; 34(10): 1207-19, 2015 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-24681956

RESUMEN

B-cell lymphoma/leukemia 10 (BCL10) is an apoptotic regulatory protein related to advanced TNM stage and disease recurrence in oral squamous cell carcinoma (OSCC). However, the regulatory mechanism of BCL10 in OSCC progression is still unknown. Here, we showed that knockdown of endogenous BCL10 could significantly reduce cell migration and invasion abilities, retard cell proliferation by G0/G1 phase accumulation and inhibit tumorigenicity in vivo. In molecular level, we identified S100P as a crucial downstream effector of BCL10-inhibited OSCC progression by high-throughput microarray analysis. S100P messenger RNA and protein expression levels were significantly diminished in silenced-BCL10 clones, and transfected S100P expression plasmids restored migration, invasion, proliferation abilities and tumorigenicity in shBCL10 transfectants. Furthermore, we provided evidence that BCL10 regulated S100P expression through signal transducers and activators of transcription 1 (STAT1) and activating transcription factor 4 (ATF4). Knockdown of BCL10 decreased S100P promoter activity, but showed no effect in truncated STAT1/ATF4 S100P promoter.  In addition, we also found that the P50/P65 signaling pathway was involved in BCL10-enhanced OSCC progression. Restored S100P in silenced-BCL10 clones could markedly reverse P65 activation via outside-in signaling. Taken together, we discovered a novel axis of BCL10-regulated OSCC progression via STAT1/ATF4/S100P/P65 signaling, which could predict the prognosis of OSCC and will be beneficial for developing therapeutic strategy against advanced OSCC.


Asunto(s)
Factor de Transcripción Activador 4/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas de Unión al Calcio/metabolismo , Neoplasias de la Boca/metabolismo , Proteínas de Neoplasias/metabolismo , Factor de Transcripción STAT1/metabolismo , Transducción de Señal , Factor de Transcripción Activador 4/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Proteína 10 de la LLC-Linfoma de Células B , Sitios de Unión , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Técnicas de Silenciamiento del Gen , Xenoinjertos , Humanos , Ratones , Neoplasias de la Boca/genética , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/patología , Pronóstico , Unión Proteica , Activación Transcripcional
14.
Biomaterials ; 24(25): 4591-601, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12951002

RESUMEN

This study used synchrotron X-ray microtomography on a micron scale to compare three-dimensional (3D) bone ingrowth after implantation of various calcium phosphate bone substitutes in a rabbit model. The advantage of using this new method for the study of biomaterials was then compared with histomorphometry for analysis of interconnection and bone ingrowth. The study focused on the newly formed bone-biomaterial interface. Macroporous Biphasic Calcium Phosphate (MBCP) ceramic blocks and two different injectable calcium phosphate biomaterials [an injectable bone substitute (IBS) consisting of a biphasic calcium phosphate granule suspension in hydrosoluble polymer and a calcium phosphate cement material (CPC)] were studied after in vivo implantation. Absorption or phase-contrast microtomography was performed with the dedicated set-up at beamline ID22. Experimental spatial resolution was between 1 and 1.4 microm, depending on experimental radiation. All calcium phosphates tested showed osteoconduction. IBS observations after 3D reconstruction showed interconnected bioactive biomaterial with total open macroporosity and complete bone ingrowth as early as 3 weeks after implantation. This experimentation was consistent with two-dimensional histomorphometric analysis, which confirmed its suitability for biomaterials. This 3D study relates the different types of bone substitution to biomaterial architecture. As porosity and interconnection increase, bone ingrowth becomes greater at the expense of the bone substitute: IBS>MBCP>CPC.


Asunto(s)
Materiales Biocompatibles/metabolismo , Sustitutos de Huesos/metabolismo , Fosfatos de Calcio/metabolismo , Imagenología Tridimensional/métodos , Implantes Experimentales , Oseointegración/fisiología , Tomografía/métodos , Animales , Cementos para Huesos/metabolismo , Ensayo de Materiales , Conejos , Sincrotrones , Tomografía/instrumentación , Rayos X
15.
QJM ; 95(8): 501-9, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12145389

RESUMEN

BACKGROUND: Despite the advent of modern neurosurgical techniques, new antibiotics, and powerful imaging technologies, brain abscess remains a potentially fatal central nervous system infection. AIM: To determine the epidemiological trends, prognostic factors, and outcomes of bacterial brain abscess, to improve the therapeutic strategy for this disease. DESIGN: Retrospective hospital-based epidemiology study. METHODS: Over a period of 15 years (1986-2000), 123 patients were retrospectively identified as having brain abscesses at Kaohsiung Chang Gung Memorial Hospital. To compare changes over time, the appearance of disease among our patients was divided into two time periods: 1986-1993 and 1994-2000. RESULTS: The prevalence rate of brain abscesses caused by Gram-negative organisms significantly increased in the second study period. Viridans streptococci and Klebsiella pneumoniae were the two prevalent pathogens associated with haematogenous spread. Metastatic septic abscess, a devastating complication of K. pneumoniae septicaemia, frequently occurs in diabetic patients, with a high mortality rate. Viridans streptococci were the most prevalent pathogens from infection in paranasal sinusitis, but no fatality occurred. In recent years, head trauma and/or post-neurosurgical states have become important predisposing factors, and nosocomial infections also play an important role. DISCUSSION: Despite the availability of new antibiotics and the development of better neurosurgical techniques, therapeutic outcomes of brain abscess showed no significant change when comparing the two study periods, and only the presence of septic shock influenced outcome.


Asunto(s)
Absceso Encefálico/epidemiología , Infecciones por Klebsiella/epidemiología , Infecciones Estreptocócicas/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Absceso Encefálico/microbiología , Absceso Encefálico/terapia , Niño , Preescolar , Femenino , Humanos , Lactante , Infecciones por Klebsiella/microbiología , Infecciones por Klebsiella/terapia , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/terapia , Taiwán/epidemiología
16.
Eur J Pharmacol ; 227(2): 225-8, 1992 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-1330652

RESUMEN

The effects of various proposed GABAB receptor antagonists on baclofen-mediated inhibition of adenylyl cyclase were studied in cultured cerebellar granule cells from rat. (+/-)-Baclofen maximally inhibited adenylyl cyclase by approximately 60% of the basal enzyme activity with an EC50 value of 10 microM. 3-Aminopropane sulfonic acid (3-APS) and 5-aminovaleric acid (5-AVA) produced similar responses to that seen with (+/-)-baclofen. Saclofen reversed the action of (+/-)-baclofen, 50 microM, with a half maximal inhibitory concentration (IC50) of about 1.0 mM. The most effective antagonist in blocking the action of (+/-)-baclofen was 3-aminopropyl-diethoxy-methyl-phosphonic acid (CGP 35,348). In the presence of (+/-)-baclofen, 50 microM, the IC50 for CGP 35,348 was 290 microM and its inhibitory constant (KA) was 180 microM. The agonist-like actions of 3-APS and 5-AVA were antagonized by CGP 35,348 suggesting that 3-APS and 5-AVA may act as weak agonists at the GABAB receptor that inhibits adenylyl cyclase. All antagonists tested, except the new compound CGP 35,348, have very low potencies at GABAB receptors that inhibit adenylyl cyclase, though these compounds have been quite effective at other GABAB receptor-mediated events. Thus, the GABAB receptor which inhibits adenylyl cyclase differs pharmacologically from other reported GABAB receptor/effector systems and supports the existence of multiple receptor subtypes.


Asunto(s)
Inhibidores de Adenilato Ciclasa , Aminoácidos Neutros , Baclofeno/farmacología , Cerebelo/efectos de los fármacos , Antagonistas de Receptores de GABA-A , Aminoácidos/farmacología , Animales , Células Cultivadas , Cerebelo/citología , Cerebelo/enzimología , Relación Dosis-Respuesta a Droga , Compuestos Organofosforados/farmacología , Ratas , Ratas Sprague-Dawley , Taurina/análogos & derivados , Taurina/farmacología
17.
J Biomed Mater Res A ; 66(1): 47-54, 2003 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-12833430

RESUMEN

The use of injectable calcium phosphate (CaP) biomaterials in noninvasive surgery should provide efficient bone colonization and implantation. Two different kinds of injectable biomaterials are presently under development: ionic hydraulic bone cements that harden in vivo after injection, and an association of biphasic calcium phosphate (BCP) ceramic granules and a water-soluble polymer vehicle (a technique particularly investigated by our group), providing an injectable CaP bone substitute (IBS). In our study, we compared these two approaches, using physicochemical characterizations and in vivo evaluations in light microscopy, scanning electron microscopy, and three-dimensional microtomography with synchrotron technology. Three weeks after implantation in rabbit bone, both biomaterials showed perfect biocompatibility and bioactivity, but new bone formation and degradation of the biomaterial were significantly greater for BCP granules than for ionic cement. Newly formed bone developed, binding the BCP granules together, whereas new bone grew only on the surface of the cement, which remained dense, with no obvious degradation 3 weeks after implantation. This study confirms that BCP granules carried by a cellulosic polymer conserve bioactivity and are conducive to earlier and more extensive bone substitution than a carbonated-hydroxyapatite bone cement. The presence of intergranular spaces in the BCP preparation, as shown on microtomography imaging, seems particularly favorable, allowing body fluids to reach each BCP granule immediately after implantation. Thus, the IBS functions as a completely interconnected ceramic with total open macroporosity. This new bone replacement approach should facilitate microinvasive bone surgery and local delivery of bone therapy agents.


Asunto(s)
Materiales Biocompatibles , Sustitutos de Huesos , Fosfatos de Calcio/administración & dosificación , Animales , Cementos para Huesos , Fosfatos de Calcio/química , Cerámica , Fémur , Imagenología Tridimensional , Inyecciones , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Agujas , Oseointegración , Porosidad , Conejos , Propiedades de Superficie , Sincrotrones , Tomografía/métodos , Viscosidad
18.
J Periodontol ; 61(3): 189-96, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2181111

RESUMEN

The association of bacteroides gingivalis, Bacteroides forsythus, Treponema denticola, and Actinobacillus actinomycetemcomitans among others with periodontal disease offers the opportunity for the development of diagnostic tests that are based upon the detection and/or quantification of one or more of these organisms or their by-products in the plaque. Three of the putative periodontal pathogens namely, T. denticola, B. gingivalis, and B. forsythus, can hydrolyze the synthetic trypsin substrate, N-benzoyl-DL-arginine-2-naphthylamide (BANA) forming a color reaction. The present investigation evaluated a commercially developed solid state assay for BANA hydrolysis that can be read after 15 minutes incubation at chairside. A total of 702 subgingival plaque samples were collected from 117 patients seen at four university dental clinics and placed on reagent cards. The color development on the cards was compared to the presence of T. denticola and B. gingivalis in the plaque, and with the clinical appearance of the sampled sites. This multi-center study demonstrated that antibodies to B. gingivalis and T. denticola could detect these organisms by an ELISA in the majority of the subgingival plaque samples. Comparable information could be obtained when the same plaques were evaluated by the reagent card format for BANA hydrolysis. The ELISA and reagent card were comparable in their ability to distinguish between clinically healthy and diseased sites. Both diagnostic procedures detected the periodontopathogens in plaques from sites that were judged clinically healthy.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Arginina/análogos & derivados , Benzoilarginina-2-Naftilamida , Placa Dental/microbiología , Enfermedades Periodontales/microbiología , Tiras Reactivas , Adulto , Bacteroides/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Hemorragia Gingival/patología , Humanos , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Enfermedades Periodontales/diagnóstico , Treponema/aislamiento & purificación
19.
Auton Neurosci ; 86(1-2): 99-106, 2000 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-11269931

RESUMEN

Transthoracic endoscopic T2 sympathectomy has been widely applied to the treatment of a variety of sympathetically mediated disorders. Palmar hyperhidrosis is probably the most common indication for thoracic sympathectomy, especially in certain subtropical areas. Which sympathetic ganglion is to be ablated and how extensive such ablation is enough to eliminate palm sweating are two important issues. Intraoperative monitoring of palmar skin temperature (PST) is the most frequently used method for assessing the accuracy as well as adequacy of ablation of the target sympathetic ganglia. With continuous monitoring of bilateral PST during the operative course of T2 sympathectomy, it was possible to depict the alterations of bilateral PST in response to specific surgical procedures in a real-time manner. For each case, a PST graph was obtained, which represented the graphical expression of intraoperatively recorded bilateral PST data plotted against time. The PST graphs of 93 consecutive cases were analysed. Three types of PST graphs existed, reflecting different responses of bilateral PST to different surgical procedures during the operation. In Type I PST graph pattern, found in 58 cases, skin incision and intercostal muscle dissection caused dramatic bilateral PST drop; and unilateral T2 sympathectomy induced synchronous bilateral PST elevation. Twenty-four cases demonstrated Type II PST graph pattern, in which unilateral T2 sympathectomy caused only ipsilateral PST elevation, although the PST-depressing effect of skin incision and muscle dissection was as significant as in Type I graph pattern. In the 11 cases who showed Type III PST graph pattern, neither skin incision nor T2 sympathectomy induced any apparent changes of PST on either side, giving rise to two rather flat PST curves on the PST graphs. These findings implicate that reciprocal interactions between bilateral sympathetic activities exist in the majority of cases, and that crossover sympathetic modulation may play a role in the neural control of the sudomotor and vasomotor activities of the palms. This study also provides information regarding how PST would possibly change following specific surgical procedures during transthoracic endoscopic T2 sympathectomy, which may be of importance to those who use intraoperative PST monitoring as a guide in determining whether or not the correct sympathetic ganglia are ablated for adequate sympathetic denervation of the palms.


Asunto(s)
Ganglios Simpáticos/cirugía , Mano/fisiopatología , Hiperhidrosis/cirugía , Temperatura Cutánea/fisiología , Adolescente , Adulto , Niño , Femenino , Mano/inervación , Humanos , Hiperhidrosis/fisiopatología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Glándulas Sudoríparas/inervación , Glándulas Sudoríparas/fisiopatología , Simpatectomía , Vértebras Torácicas , Toracoscopía , Resultado del Tratamiento
20.
Surg Neurol ; 56(3): 189-94, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11597651

RESUMEN

BACKGROUND: To assess the clinical features and therapeutic outcomes of brain abscess caused by streptococci. METHODS: Twenty patients, 18 males and 2 females, aged 3 to 76 years, collected over a 14-year period, have been identified at Kaohsiung Chang Gung Memorial Hospital. RESULTS: Among these 20 patients, 13 had viridans streptococci infection alone, one had non-A, non-B, and non-D streptococci infection alone, and the other 6 had mixed infections each including streptococci. The locations of all of the abscesses were supratentorial. Among these patients, 18 had a single abscess and 2 had multiple abscesses. Underlying conditions were common in our patients, including head trauma, heart disease, otopharyngeal infection, and medical procedures. Nineteen patients were treated surgically and 1 was treated with antibiotics alone. Nineteen survived and 1 died, with an overall mortality rate of 5%. CONCLUSION: The clinical presentations and underlying conditions varied according to the different streptococcal species. Streptococcal brain abscesses accounted for 17% of our cases with brain abscesses, and 30% of our streptococcal infections had polymicrobial infections. Although streptococcal brain abscesses were commonly associated with otopharyngeal infections or infectious endocarditis, they also appeared to be often related to neurosurgical events or medical procedures in recent years. Based on our study, prognosis is favorable with early diagnosis and prompt treatment.


Asunto(s)
Absceso Encefálico/diagnóstico , Absceso Encefálico/etiología , Infecciones Estreptocócicas/complicaciones , Infecciones Estreptocócicas/diagnóstico , Adolescente , Adulto , Anciano , Antibacterianos/uso terapéutico , Absceso Encefálico/terapia , Causalidad , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Infecciones Estreptocócicas/terapia , Resultado del Tratamiento
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