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2.
Sci Adv ; 5(9): eaaw1164, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31579819

RESUMEN

Modeling of postseismic deformation following great earthquakes has revealed the viscous structure of the mantle and the frictional properties of the fault interface. However, for giant megathrust events, viscoelastic flow and afterslip mechanically interplay with each other during the postseismic period. We explore the role of afterslip and viscoelastic relaxation and their interaction in the aftermath of the 2011 M w (moment magnitude) 9.0 Tohoku earthquake based on a detailed model analysis of the postseismic deformation with laterally varying, experimentally constrained, rock rheology. Mechanical coupling between viscoelastic relaxation and afterslip notably modifies both the afterslip distribution and surface deformation. Thus, we highlight the importance of addressing mechanical coupling for long-term studies of postseismic relaxation, especially in the context of the geodynamics of the Japan trench across the seismic cycle.

5.
Neurochirurgie ; 63(3): 164-174, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28162255

RESUMEN

INTRODUCTION: The aim of brain glioma surgery is to maximize the quality of resection, while minimizing the risk of sequelae. Due to the frequent location of gliomas near or within eloquent areas, owing to their infiltrative feature, and because of major interindividual variability, the anatomofunctional organization and connectivity must be studied individually. Therefore, to optimize the benefit-to-risk ratio of surgery, intraoperative functional mapping is extensively used. MATERIAL AND METHODS: This article aims at describing the rationale, indications and practical aspects of intraoperative direct electrical bipolar electrostimulation for cortical and subcortical mapping under awake conditions using the asleep-awake asleep anaesthetic protocol in the setting of cerebral gliomas. We will address the operative approach, including patient positioning, functional mapping resection strategy, anaesthetic conditions, as well as tips and pitfalls. RESULTS: The intraoperative direct electrical bipolar electrostimulation enables: (i) to study the real-time individual cortical functional organization; (ii) to study the anatomofunctional subcortical connectivity along the resection; (iii) to tailor the resection according to individual corticosubcortical functional boundaries. This is an easy, accurate, reliable, well-tolerated and safe detection technique of both cortical and subcortical functionally essential structures during resection. It should be performed in the context of a standardized protocol involving members of both anaesthesiology and neurosurgery teams at neurosurgical centers specialized in surgical neuro-oncology. CONCLUSION: Intraoperative direct electrical bipolar electrostimulation for cortical and subcortical mapping under awake conditions is currently considered the "gold standard" clinical tool for brain mapping during cerebral resection in neuro-oncology.


Asunto(s)
Neoplasias Encefálicas/cirugía , Estimulación Eléctrica , Glioma/cirugía , Monitorización Neurofisiológica Intraoperatoria , Procedimientos Neuroquirúrgicos , Vigilia/fisiología , Mapeo Encefálico/métodos , Neoplasias Encefálicas/patología , Estimulación Eléctrica/métodos , Glioma/complicaciones , Humanos , Procedimientos Neuroquirúrgicos/métodos
6.
J Eur Acad Dermatol Venereol ; 30(9): 1544-9, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27060697

RESUMEN

BACKGROUND: Neutrophil elastase plays an important role in skin inflammation induced by neutrophil infiltration. Elafin is an inducible elastase inhibitor expressed by keratinocytes, and is known to be involved in pathogenesis of neutrophilic skin disorders such as psoriasis. METHODS: Immunohistochemical studies of elafin expression in the cases of vasculitis were performed. Induction of elafin expression in cultured vascular cells and its effect on neutrophil migration were studied in vitro. RESULTS: A positive immunoreactivity was detected in polyarteritis nodosa, giant cell arteritis and Schönlein-Henoch purpura, but no immunoreactivity was found in Churg-Strauss syndrome. Elafin expression in cultured venous endothelial cells and arterial smooth muscle cells was undetectable, but induced by interleukin-1ß (IL-1ß) and IL-8. Elafin inhibited the elastin peptide-induced neutrophil chemotaxis at the concentration of 10(-8) -10(-5) mol/L. CONCLUSION: Elafin deposition induced by cytokines (IL-1ß or IL-8) will be an important regulator for the progress of leucocytoclastic vasculitis by functioning as an inhibitor for neutrophil chemotaxis as well as for vascular elastin degradation.


Asunto(s)
Elafina/metabolismo , Neutrófilos/patología , Piel/irrigación sanguínea , Túnica Íntima/metabolismo , Vasculitis/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Células Cultivadas , Quimiotaxis de Leucocito , Citocinas/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
7.
J Laryngol Otol ; 129(8): 752-61, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26165313

RESUMEN

BACKGROUND AND METHODS: Reconstruction with a vascularised flap provides the most reliable outcome, with post-operative cerebrospinal fluid leak rates of less than 5 per cent. This article aims to review and summarise the critical technical aspects of the vascularised flaps most commonly used for skull base reconstruction. RESULTS: Vascularised flaps are classified as intranasal or extranasal. The intranasal group includes the Hadad-Bassagaisteguy nasoseptal flap, the Caicedo reverse nasoseptal flap, the nasoseptal rescue flap, the posteriorly or anteriorly based lateral wall flaps, and the middle turbinate flap. Extranasal flaps include the transfrontal pericranial and transpterygoid temporoparietal flaps. CONCLUSION: The Hadad-Bassagaisteguy nasoseptal flap is overwhelmingly favoured for reconstructing extensive defects of anterior, middle and posterior cranial base. Its pertinent technical features are described. However, it is essential to master the skills required for the various extranasal or regional vascularised flaps because each can offer a reconstructive alternative for specific patients, especially when open approaches are needed and/or intranasal vascularised flaps are not feasible.


Asunto(s)
Procedimientos de Cirugía Plástica/métodos , Neoplasias de la Base del Cráneo/cirugía , Base del Cráneo/cirugía , Colgajos Quirúrgicos/irrigación sanguínea , Colgajos Quirúrgicos/cirugía , Pérdida de Líquido Cefalorraquídeo/prevención & control , Endoscopía/métodos , Humanos , Microcirugia/métodos , Complicaciones Posoperatorias/prevención & control , Base del Cráneo/irrigación sanguínea , Recolección de Tejidos y Órganos/métodos
8.
J Anal Toxicol ; 30(8): 576-80, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17132255

RESUMEN

Duloxetine (Cymbalta) is manufactured by Eli Lilly and Company and is the newest antidepressant to be approved by the Food and Drug Administration (FDA). Duloxetine is a potent serotonin and norepinephrine reuptake inhibitor that is also used for the management of pain associated with diabetic peripheral neuropathy. With the introduction of any new drug, toxicology laboratories around the nation experience the same problems: lack of information about the chemical and physical properties of the new drug, detection methodologies from biological specimens, and interpretation of quantitative values. Since its FDA approval in 2002, the Los Angeles County Department of Coroner Toxicology Laboratory has detected and quantitated duloxetine in 12 postmortem cases. The isolation of duloxetine from postmortem specimens consisted of a basic, liquid-liquid (n-butylchloride) extraction procedure. Duloxetine was detected in our general, pharmaceutical, basic drugs screen that utilizes gas chromatography-nitrogen-phosphorus detection (GC-NPD) and GC-mass spectrometry (MS), and the quantitation was specifically by GC-MS. Linearity was achieved from 0.05 to 3.0 mg/L with the limit of detection at 0.03 mg/L. Presented are the case histories, demographics, cause/manner of death, and the postmortem tissue distribution ranges of duloxetine: central blood, not detected (ND)-0.59 mg/L (12 cases); femoral blood, ND-0.26 mg/L (9 cases); vitreous humor, ND-0.23 mg/L (4 cases); liver, 0.28-22 mg/kg (8 cases); gastric contents, 0.08-86 mg total (6 cases); bile, 0.57-3.1 mg/L (7 cases); and urine, 0.07-0.47 mg/L (6 cases). The detection and quantitation of duloxetine in these 12 case studies are considered the first to be reported in the literature; all are designed to aid the forensic toxicologist with the interpretation of his/her own casework.


Asunto(s)
Antidepresivos/análisis , Toxicología Forense/métodos , Tiofenos/análisis , Adulto , Antidepresivos/farmacocinética , Clorhidrato de Duloxetina , Resultado Fatal , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Persona de Mediana Edad , Tiofenos/farmacocinética
10.
J Microsc ; 216(Pt 3): 222-8, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15566493

RESUMEN

A new method of microinfrared reflection spectroscopy and mapping analysis is briefly introduced. It was used to detect distributions and structures of hydrogen-related species (e.g. H(2)O, SiOH and SiH) in plastically deformed natural quartz. We used a Fourier transform-infrared spectrometer with a microscopic imaging system fully automated for all microscope functions (e.g. focusing, aperture, stage motion and measurements). Mapping can be made in thin sections with a thickness of 50 microm at room temperature and low temperatures (77 K) using a liquid N(2) cooling system. Infrared reflection spectra were obtained by five scans for each point with a range from 4000 to 400 cm(-1). The spectra were measured five times within about 2.5 s at each position. The scanning interval was 100-150 microm using a 100 x 100 microm(2) aperture. All obtained spectral data were stored in computer memory to construct two-dimensional mappings of infrared absorption. From the comparisons between infrared mapping images and deformation microstructures, in addition to the molecular H(2)O around 3600-3400 cm(-1), the hydrogen-related point defects (i.e. SiOH and SiH) around 970-900 cm(-1) within quartz grains and between grain boundaries increased with decreasing grain sizes (increasing plastic strain). The method can detect the SiOH and SiH along grain boundaries that enhance the hydrolytic weakening of natural quartz.

12.
J Anal Toxicol ; 24(7): 627-34, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11043670

RESUMEN

Fentanyl is a potent, short-acting narcotic analgesic widely used as a surgical anesthetic and for the control of pain when administered in the form of a transdermal patch. The success of the patch can be attributed to fentanyl's low molecular weight and its highly lipophilic nature, which enables it to be readily absorbed through the skin and subsequently distributed throughout the body. Over the past three years, the Los Angeles County Coroner's Toxicology Laboratory has encountered 25 cases involving Duragesic patches (fentanyl), and their postmortem tissue distributions are presented here. The analysis of fentanyl from postmortem specimens (3-mL or g sample size) consisted of an n-butyl chloride basic extraction followed by identification and quantitation on a gas chromatograph-mass spectrometer using the selected ion monitoring (SIM) mode. The fentanyl ions monitored were m/z 245, 146, and 189 and the internal standard, fentanyl-d5 ions, were m/z 250, 151, and 194 (quantitation ion underlined). The linear range of the assay was 1.67 microg/L to 500 microg/L with the limit of quantitation and detection of 1.67 microg/L. The postmortem tissue distribution ranges of fentanyl in the 25 fatalities were as follows: heart blood, 1.8-139 microg/L (23 cases); femoral blood, 3.1-43 microg/L (13 cases); vitreous, +<2.0-20 microg/L (4 cases); liver, 5.8-613 microg/kg (22 cases); bile, 3.5-262 microg/L (15 cases); urine, 2.9-895 microg/L (19 cases); gastric, 0-1200 microg total (17 cases); spleen, 7.8-79 microg/kg (3 cases); kidney, 11 microg/kg (1 case); and lung, 31 microg/kg (1 case). The age of the decedents in this study ranged from 19 to 84, with an average age of 46. The modes of death included 15 accidental, 5 natural, 3 suicidal, and 2 undetermined. The main objectives of this paper are to show the prevalence of fentanyl patches in our community and to aid the forensic toxicologist with the interpretation of postmortem fentanyl levels in casework.


Asunto(s)
Analgésicos Opioides/farmacocinética , Analgésicos Opioides/envenenamiento , Fentanilo/farmacocinética , Fentanilo/envenenamiento , Trastornos Relacionados con Opioides/diagnóstico , Administración Cutánea , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos Opioides/administración & dosificación , Autopsia/métodos , Causas de Muerte , Femenino , Fentanilo/administración & dosificación , Cromatografía de Gases y Espectrometría de Masas/instrumentación , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Masculino , Persona de Mediana Edad , Trastornos Relacionados con Opioides/complicaciones , Detección de Abuso de Sustancias/métodos , Suicidio , Distribución Tisular
13.
J Anal Toxicol ; 23(6): 544-8, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10517565

RESUMEN

Mirtazapine is a new antidepressant agent that entered the United States market in April 1996. To date, the literature provides limited information about therapeutic blood concentrations and virtually no information about postmortem levels. The Los Angeles County Coroner's Toxicology Laboratory has encountered 13 cases where postmortem tissue distributions of mirtazapine were determined. The analysis of mirtazapine from postmortem specimens (2-mL sample size) consisted of an n-butylchloride basic extraction procedure with identification and quantitation on a gas chromatograph-nitrogen-phosphorus detector. Linearity was achieved from 0.025 mg/L to 3.0 mg/L with a limit of quantitation of 0.025 mg/L. Confirmation of mirtazapine was performed on a gas chromatograph-mass spectrometer by comparison with a pure analytical standard. The tissue distribution of mirtazapine are in the following concentration ranges: heart blood 0.03-0.57 mg/L (13 cases), femoral blood 0.04-0.24 mg/L (9 cases), vitreous 0.06-0.10 mg/L (3 cases), liver 0.32-2.1 mg/kg (12 cases), bile 0.40-6.6 mg/L (7 cases), urine 0.12-2.5 mg/L (11 cases), kidney 0.23 mg/kg (1 case), spleen 0.17 mg/kg (1 case), and gastric 0.001-2.7 mg total (9 cases). Mirtazapine was not implicated in the cause of death in any of the 13 cases studied. These cases are being presented to aid the forensic toxicologist in the evaluation of postmortem mirtazapine levels.


Asunto(s)
Antidepresivos Tricíclicos/farmacocinética , Mianserina/análogos & derivados , Distribución Tisular/fisiología , Adulto , Anciano , Autopsia , Cromatografía de Gases , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Mianserina/farmacocinética , Persona de Mediana Edad , Mirtazapina
14.
Nihon Jibiinkoka Gakkai Kaiho ; 101(2): 198-204, 1998 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-9545765

RESUMEN

As part of a study on chronic inflammatory disease of the mucous membrane, silicon of the medium in postoperative maxillary cysts and in other cysts was measured, and following results were obtained. Silicon concentrations of the medium in the postoperative maxillary cysts and in the postoperative ethmoidal cysts were 34.5 ppm and 42.9 ppm (geometrical mean) respectively, and they were higher than in other primary cysts such as frontal cyst, nasal vestibular cyst, and dental cyst. The silicon content of the medium in the postoperative maxillary cyst varied with the water content of the medium; the lower the water content the higher was the silicon content and the relationship was expressed by the following equation. log S = 7.43 + 7.14 log d-6.14 log w, where S = Si (mcg), d = dry weight (g.) and w = wet weight (g.). The high concentration of silicon in the postoperative cyst was considered to be due to the large amount of silicon transudate from the surrounding fibrous tissue through a highly damaged or missing epithelial wall of the cyst.


Asunto(s)
Quistes/metabolismo , Quistes/cirugía , Enfermedades Maxilares/metabolismo , Enfermedades Maxilares/cirugía , Silicio/análisis , Femenino , Humanos , Masculino , Periodo Posoperatorio , Silicio/farmacocinética
18.
Gan To Kagaku Ryoho ; 21 Suppl 4: 477-80; discussion 481, 1994 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-7528490

RESUMEN

From April 1987 to June 1994, 81 patients of terminally ill had been care at home. In these home care, 38 patients received pain control with morphine. In 29 patients, pain control had been started before home care but in 9 patients pain control had been started under home care. Routes of morphine administration were oral in 24 cases and rectal in 14 cases. In cases of oral routes, finally 2 cases converted to rectal routes and 2 cases converted to subcutaneous routes. Duration of treatment were from 2 days to 741 days (average 72 days). Dosage of morphine were 7.5 mg to 480 mg (average 116 mg). Two patients lived but 24 patients died at home and 12 patients died at hospital. We concluded that palliative care especially pain control with morphine was very important care for patients of terminally ill who wanted care at home and ultimately die at home. We had to make ourself master of method pain control with morphine.


Asunto(s)
Servicios de Atención a Domicilio Provisto por Hospital , Morfina/uso terapéutico , Neoplasias/fisiopatología , Dolor Intratable/tratamiento farmacológico , Cuidados Paliativos , Administración Oral , Administración Rectal , Humanos , Morfina/administración & dosificación
19.
J Anal Toxicol ; 16(5): 340-2, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1294843

RESUMEN

Automating the initial screening of postmortem blood and other tissues for drugs of abuse requires a pipetting procedure that is compatible with immunoassay screening tests. The deproteinization procedure uses a zinc sulfate-5-sulfosalicylic acid reagent to precipitate blood proteins. This procedure for deproteinization of whole blood and tissue homogenates is compatible with coated tube radioimmunoassays (RIA) and can therefore be used in automating the initial screening step.


Asunto(s)
Drogas Ilícitas/sangre , Detección de Abuso de Sustancias/métodos , Automatización , Cromatografía de Gases y Espectrometría de Masas , Humanos , Fenciclidina/sangre , Cambios Post Mortem , Radioinmunoensayo , Reproducibilidad de los Resultados
20.
J Forensic Sci ; 36(4): 1074-8, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1919469

RESUMEN

Cocaine has recently been shown to affect the outcome of pregnancy when taken by pregnant women. The authors measured fetal concentrations of cocaine and benzoylecgonine and reviewed autopsy and historical data for 62 successive infants who died at less than two days of age and were seen at the Los Angeles County Office of the Chief Medical Examiner-Coroner. Of 43 infants without an obvious cause of death at autopsy, cocaine or benzoylecgonine or both were present in 40%. None of the parameters studied predicted which infants would show cocaine or benzoylecgonine. We conclude that cocaine and benzoylecgonine concentrations should be measured on all infants who die at less than two days of age when the cause of death is not evident at gross autopsy.


Asunto(s)
Causas de Muerte , Cocaína , Complicaciones del Embarazo , Resultado del Embarazo , Trastornos Relacionados con Sustancias/complicaciones , Autopsia , Química Encefálica , Cocaína/análogos & derivados , Cocaína/análisis , Cocaína/sangre , Femenino , Muerte Fetal/etiología , Humanos , Recién Nacido , Hígado/química , Embarazo
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