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1.
J Intern Med ; 289(2): 193-205, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32654192

RESUMEN

BACKGROUND: Extracellular fluid volume (ECF) is independently associated with chronic kidney disease (CKD) progression and mortality in patients with CKD, but the prognostic value of the trajectory of ECF over time beyond that of baseline value is unknown. OBJECTIVES: To characterize ECF trajectory and evaluate its association with the risks of end-stage kidney disease (ESKD) and mortality. METHODS: From the prospective tricentric NephroTest cohort, we included 1588 patients with baseline measured glomerular filtration rate (mGFR) ≥15 mL min-1 /1.73 m2 and ECF measurement. ECF and GFR were measured repeatedly using the distribution volume and clearance of 51 Cr-EDTA, respectively. ESKD and mortality were traced through record linkage with the national registries. Adjusted shared random-effect joint models were used to analyse the association between the trajectory of ECF over time and the two competing outcomes. RESULTS: Patients were mean age 58.7 years, 66.7% men, mean mGFR of 43.6 ± 18.6 mL min-1 /1.73 m2 and mean ECF of 16.1 ± 3.6 L. Over a median follow-up of 5.3 [IQR: 3.0;7.4] years, ECF increased by 136 [95%CI 106;167] mL per year on average, whilst diuretic prescription and 24-hour urinary sodium excretion remained stable. ESKD occurred in 324 (20.4%) patients, and 185 (11.6%) patients died before ESKD. A higher current value of ECF was associated with increased hazards of ESKD (adjusted hazard ratio [aHR]: 1.12 [95%CI 1.06;1.18]; P < 0.001 per 1 L increase in ECF), and death before ESKD (aHR: 1.10 [95%CI 1.04;1.17]; P = 0.002). CONCLUSIONS: The current value of ECF was associated with the risks of ESKD and mortality, independent of multiple potential confounders, including kidney function decline. This highlights the need for a close monitoring and adjustment of treatment to avoid fluid overload in CKD patients.


Asunto(s)
Líquido Extracelular/metabolismo , Fallo Renal Crónico/mortalidad , Progresión de la Enfermedad , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Factores de Riesgo
2.
Infection ; 41(2): 537-43, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23203899

RESUMEN

PURPOSE: Tuberculous paradoxical reactions (PR) have been seldom studied in non-immunocompromised patients. We conducted a study to describe the incidence, clinical and biological features, treatment and outcome of PR in human immunodeficiency virus (HIV)-negative patients treated for extrapulmonary tuberculosis (TB) and to identify predictive factors of PR. METHODS: A single-center retrospective study was conducted in consecutive HIV-negative patients presenting with TB with at least one extrapulmonary manifestation who were hospitalized in an internal medicine department between 2000 and 2010. RESULTS: Seventy-six patients were enrolled in the study. Lymphadenitis was the most common extrapulmonary manifestation of tuberculosis among this patient population (72 %). PR occurred in 19 (25 %) patients, mostly involving the lymph nodes (68 %) and lung (16 %), but also the pericardium, pleura, bone, muscle and brain. Median time to PR onset after initiation of anti-TB regimen was 86 days (interquartile range 36-125). Treatment of PR consisted mainly of corticosteroids (47 % of patients) and needle aspiration of PR lymph nodes (31 %). Peripheral lymph node involvement (p = 0.009), lymphopenia (p = 0.03) and anemia (p = 0.002) at presentation were associated with PR occurrence. Outcome was favorable in all patients with PR but one; the latter suffered residual paraplegia. CONCLUSIONS: Paradoxical reactions are frequent in the course of extrapulmonary TB treatment in HIV-negative patients but their outcome is excellent, except in some cases with central nervous system involvement.


Asunto(s)
Antituberculosos/efectos adversos , Seronegatividad para VIH , Tuberculosis Ganglionar/tratamiento farmacológico , Adulto , Anemia/microbiología , Anemia/patología , Femenino , Hospitalización , Humanos , Incidencia , Estimación de Kaplan-Meier , Pulmón/patología , Ganglios Linfáticos/patología , Linfadenitis/microbiología , Masculino , Persona de Mediana Edad , Pericardio/patología , Pleura/microbiología , Pleura/patología , Estudios Retrospectivos , Resultado del Tratamiento , Tuberculosis Ganglionar/microbiología , Tuberculosis Ganglionar/patología
3.
J Viral Hepat ; 19(7): 497-500, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22676362

RESUMEN

Therapeutic options in hepatitis C virus (HCV)-related vasculitis may target the viral trigger using antiviral therapy [pegylated interferon plus ribavirin (PEG-IFN/RBV)], and/or the downstream B-cell arm of autoimmunity with rituximab (RTX). To date, no study has compared the efficacy of RTX combined with PEG-IFN/RBV on biomarkers of liver insufficiency in patients with severe liver fibrosis. Twenty-eight untreated HCV-related vasculitis patients with severe liver fibrosis (Metavir F3-F4) were included: 14 patients received RTX plus PEG-IFN/RBV and 14 patients PEG-IFN/RBV. The main clinical and biological data were recorded and compared at baseline, month 3 (M3), M12 and M24 of follow-up. Baseline epidemiological, clinical, virological and immunological features were similar between the groups. The virological response did not differ between cases and controls. The alanine aminotransferase (ALT) level and HCV viral load did not increase in patients treated with RTX. Serum albumin levels increased in patients treated with RTX at M3 and M6 (108% and 111% of baseline value; P = 0.06 and P = 0.13), whereas it was stable in patients treated without RTX. FibroTest values decreased from 0.70 at baseline to 0.59 at M3 (P = 0.5) and returned to 0.69 at M24 in the RTX-PEG-IFN/RBV group, whereas they were stable in the PEG-IFN/RBV group. RTX is safe in patients with severe HCV liver fibrosis and vasculitis. No beneficial effects of RTX were evidenced on liver fibrosis progression, but we found interesting correlations with the serum albumin level, FibroTest values and B-cell count.


Asunto(s)
Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Antivirales/administración & dosificación , Biomarcadores/sangre , Insuficiencia Hepática/patología , Interferones/administración & dosificación , Cirrosis Hepática/patología , Ribavirina/administración & dosificación , Anciano , Alanina Transaminasa/sangre , Monitoreo de Drogas , Femenino , Hepacivirus/aislamiento & purificación , Insuficiencia Hepática/tratamiento farmacológico , Humanos , Cirrosis Hepática/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Rituximab , Resultado del Tratamiento , Carga Viral
4.
J Hosp Infect ; 107: 28-34, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32980490

RESUMEN

INTRODUCTION: Pancreatic surgery is associated with high morbidity, mainly due to infectious complications, so many centres use postoperative antibiotics (ATBpo) for all patients. However, antibiotic regimens vary according to local practices. The aims of this study were to describe the occurrence of surgical site infection (SSI) and ATBpo prescription after pancreatic surgery, and to determine the risk factors of postoperative SSI, in order to better define the clinical indications for ATBpo in this context. PATIENTS AND METHODS: All patients undergoing scheduled major pancreatic surgery from January 2007 to November 2018 were included in this retrospective study. Patients were classified into four groups according to SSI and routine ATBpo prescription: SSI+/ATBpo+, SSI-/ATBpo+, SSI+/ATBpo- and SSI-/ATBpo-. In addition, risk factors (fever and pre-operative biliary prosthesis) associated with the occurrence of SSI and ATBpo were analysed using a logistic regression model. RESULTS: Data from 149 patients (115 pancreaticoduodenectomies and 34 splenopancreatectomies) were analysed. Thirty (20.1%) patients experienced SSI and 42 (28.2%) received ATBpo. No difference was found in routine ATBpo prescription between patients with and without SSI (26.7% vs 28.6%, respectively; P=0.9). Amongst the 107 patients who did not receive routine ATBpo, 85 (79.4%) did not develop an SSI. In-hospital mortality did not differ between infected and uninfected patients (7% vs 2%, respectively; P=0.13). The occurrence of postoperative fever differed between SSI+ and SSI- patients (73.3% vs 34.2%, respectively; P<0.001), while the prevalence of pre-operative biliary prosthesis was similar (37.9% vs 26.7%, respectively; P=0.3). CONCLUSION: Non-routine ATBpo after major pancreatic surgery resulted in 85 (56%) patients being spared unnecessary antibiotic treatment. This suggests that routine ATBpo prescription could be excessive, but further studies are needed to confirm such antibiotic stewardship. Fever appears to be a relevant clinical sign for individual-based prescription, but the presence of a biliary prosthesis does not.


Asunto(s)
Profilaxis Antibiótica , Programas de Optimización del Uso de los Antimicrobianos , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Infección de la Herida Quirúrgica , Antibacterianos/uso terapéutico , Humanos , Páncreas/cirugía , Estudios Retrospectivos , Factores de Riesgo , Infección de la Herida Quirúrgica/tratamiento farmacológico
5.
Ann Intensive Care ; 10(1): 49, 2020 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-32335780

RESUMEN

BACKGROUND: The echocardiography working group of the European Society of Intensive Care Medicine recognized the need to provide structured guidance for future CCE research methodology and reporting based on a systematic appraisal of the current literature. Here is reported this systematic appraisal. METHODS: We conducted a systematic review, registered on the Prospero database. A total of 43 items of common interest to all echocardiography studies were initially listed by the experts, and other "topic-specific" items were separated into five main categories of interest (left ventricular systolic function, LVSF n = 15, right ventricular function, RVF n = 18, left ventricular diastolic function, LVDF n = 15, fluid management, FM n = 7, and advanced echocardiography techniques, AET n = 17). We evaluated the percentage of items reported per study and the fraction of studies reporting a single item. RESULTS: From January 2000 till December 2017 a total of 209 articles were included after systematic search and screening, 97 for LVSF, 48 for RVF, 51 for LVDF, 36 for FM and 24 for AET. Shock and ARDS were relatively common among LVSF articles (both around 15%) while ARDS comprised 25% of RVF articles. Transthoracic echocardiography was the main echocardiography mode, in 87% of the articles for AET topic, followed by 81% for FM, 78% for LVDF, 70% for LVSF and 63% for RVF. The percentage of items per study as well as the fraction of study reporting an item was low or very low, except for FM. As an illustration, the left ventricular size was only reported by 56% of studies in the LVSF topic, and half studies assessing RVF reported data on pulmonary artery systolic pressure. CONCLUSION: This analysis confirmed sub-optimal reporting of several items listed by an expert panel. The analysis will help the experts in the development of guidelines for CCE study design and reporting.

6.
J Exp Psychol Hum Percept Perform ; 34(2): 475-88, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18377183

RESUMEN

The use of visual occlusion as a cue to altitude maintenance in low-altitude flight (LAF) was investigated. The extent to which the ground surface is occluded by 3-D objects varies with altitude and depends on the height, radius, and density of the objects. Participants attempted to maintain a constant altitude during simulated flight over an undulating terrain with trees of various heights, radii, and densities. As would be predicted if participants used occlusion, root-mean-square error was related to the product of tree height and tree density (Experiment 1) and to the product of tree radius and tree density (Experiment 2). This relationship was also found for simulated terrains with a more realistic mixture of tree heights (Experiment 4). The authors present a modification to an occlusion model (T. Leung & J. Malik, 1997) that can be used to approximate occlusion in the context of LAF, and they evaluate the modified model using the present LAF data. On a practical level, simulating 3-D objects is computationally expensive. The present results suggest that performance may be maintained with fewer objects if their size is increased.


Asunto(s)
Aeronaves , Altitud , Orientación , Desempeño Psicomotor , Percepción Visual , Adulto , Aprendizaje por Asociación , Simulación por Computador , Humanos , Modelos Psicológicos , Privación Sensorial , Interfaz Usuario-Computador
7.
Rev Med Interne ; 29(7): 568-72, 2008 Jul.
Artículo en Francés | MEDLINE | ID: mdl-18192090

RESUMEN

INTRODUCTION: Purulent pneumoccocal pericarditis are extremely rare since the introduction of antibiotics. EXEGESIS: A 59-year-old woman presented to the emergency room with a seven-day history of dyspnea and fever. No signs of heart failure or cardiac friction rub were evidenced. Laboratory tests disclosed elevated acute phase reactants and elevated white blood cells with a high neutrophil count. Chest radiograph showed cardiomegaly and a bilateral pleural effusion. Chest-computed tomography confirmed the pleural effusion and evidenced a large pericardial effusion. Streptoccocus pneumoniae grew up form pericardial fluid and blood cultures. In addition to the pericardial drainage, the patient received intravenous amoxicillin therapy. Outcome was favourable. There was no evidence of immunodeficiency. CONCLUSION: Although exceptional, diagnosis of purulent pneumococcal pericarditis should not be missed as it may compromise vital prognosis. Therapy should combine pericardial drainage and antibiotics.


Asunto(s)
Pericarditis/diagnóstico por imagen , Infecciones Neumocócicas/diagnóstico por imagen , Amoxicilina/administración & dosificación , Amoxicilina/uso terapéutico , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Cardiomegalia/diagnóstico por imagen , Cardiomegalia/etiología , Femenino , Humanos , Infusiones Intravenosas , Persona de Mediana Edad , Pericarditis/tratamiento farmacológico , Derrame Pleural/diagnóstico por imagen , Derrame Pleural/etiología , Infecciones Neumocócicas/tratamiento farmacológico , Radiografía Torácica , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
8.
Resuscitation ; 128: 70-75, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29698751

RESUMEN

AIM: Due to collapse and cardiopulmonary resuscitation (CPR) maneuvers, major traumatic injuries may complicate the course of resuscitation for out-of-hospital cardiac arrest patients (OHCA). Our goals were to assess the prevalence of these injuries, to describe their characteristics and to identify predictive factors. METHODS: We conducted an observational study over a 9-year period (2007-2015) in a French cardiac arrest (CA) center. All non-traumatic OHCA patients admitted alive in the ICU were studied. Major injuries identified were ranked using a functional two-level scale of severity (life-threatening or consequential) and were classified as CPR-related injuries or collapse-related injuries, depending of the predominant mechanism. Factors associated with occurrence of a CPR-related injury and ICU survival were identified using multivariable logistic regression. RESULTS: A major traumatic injury following OHCA was observed in 91/1310 patients (6.9%, 95%CI: 5.6, 8.3%), and was classified as a life-threatening injury in 36% of cases. The traumatic injury was considered as contributing to the death in 19 (21%) cases. Injuries were related to CPR maneuvers in 65 patients (5.0%, (95%CI: 3.8, 6.1%)). In multivariable analysis, age [OR 1.02; 95%CI (1.00, 1.04); p = 0.01], male gender [OR 0.53; 95%CI (0.31, 0.91); p = 0.02] and CA occurring at home [OR 0.54; 95%CI (0.31, 0.92); p = 0.02] were significantly associated with the occurrence of a CPR-related injury. CPR-related injuries were not associated with the ICU survival [OR 0.69; 95%CI (0.36, 1.33); p = 0.27]. CONCLUSIONS: Major traumatic injuries are common after cardiopulmonary resuscitation. Further studies are necessary to evaluate the interest of a systematic traumatic check-up in resuscitated OHCA patients in order to detect these injuries.


Asunto(s)
Reanimación Cardiopulmonar/efectos adversos , Paro Cardíaco Extrahospitalario/mortalidad , Heridas y Lesiones/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Servicios Médicos de Urgencia/estadística & datos numéricos , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Paris/epidemiología , Sistema de Registros , Heridas y Lesiones/etiología
9.
Resuscitation ; 103: 60-65, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27068401

RESUMEN

AIM: Hypoxic hepatitis (HH) may complicate the course of resuscitated out-of-hospital cardiac arrest (OHCA) patients admitted in intensive care unit (ICU). Aims of this study were to assess the prevalence of HH, and to describe the factors associated with HH occurrence and outcome. METHODS: We conducted an observational study over a 6-year period (2009-2014) in a cardiac arrest center. All non-traumatic OHCA patients admitted in the ICU after return of spontaneous circulation (ROSC) and who survived more than 24h were included. HH was defined as an elevation of alanine aminotransferase over 20 times the upper limit of normal during the first 72h after OHCA. Factors associated with HH and ICU mortality were picked up by multivariate logistic regression. RESULTS: Among the 632 OHCA patients included in the study, HH was observed in 72 patients (11.4% (95% CI: 9.0%, 14.1%)). In multivariate analysis, time from collapse to ROSC [OR 1.02 per additional minute; 95% CI (1.00, 1.04); p=0.01], male gender [OR 0.53; 95% CI (0.29, 0.95); p=0.03] and initial shockable rhythm [OR 0.35; 95% CI (0.19, 0.65); p<0.01] were associated with HH occurrence. After adjustment for confounding factors, HH was associated with ICU mortality [OR 4.39; 95% CI (1.71, 11.26); p<0.01] and this association persisted even if occurrence of a post-CA shock was considered in the statistical model [OR 3.63; 95% CI (1.39, 9.48); p=0.01]. CONCLUSIONS: HH is not a rare complication after OHCA. This complication is mainly triggered by the duration of resuscitation and is associated with increased ICU mortality.


Asunto(s)
Hepatitis/epidemiología , Paro Cardíaco Extrahospitalario/complicaciones , Anciano , Alanina Transaminasa/sangre , Reanimación Cardiopulmonar , Femenino , Hepatitis/complicaciones , Hepatitis/enzimología , Humanos , Hipoglucemia/complicaciones , Hipoxia/complicaciones , Incidencia , Unidades de Cuidados Intensivos/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Paro Cardíaco Extrahospitalario/mortalidad , Factores de Tiempo
10.
Resuscitation ; 92: 38-44, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25917260

RESUMEN

AIM: Low survival rate was previously described after cardiac arrest in cancer patients and may challenge the appropriateness of intensive care unit (ICU) admission after return of spontaneous circulation (ROSC). Objectives of this study were to report outcome and characteristics of cancer patients admitted to the ICU after cardiac arrest. METHODS: A retrospective chart review in seven medical ICUs in France, in 2002-2012. We studied consecutive patients with malignancies admitted after out-of-hospital cardiac arrest (OHCA) or in-hospital cardiac arrest (IHCA). RESULTS: Of 133 included patients of whom 61% had solid tumors, 48 (36%) experienced OHCA and 85 (64%) IHCA. Cardiac arrest was related to the malignancy or its treatment in 47% of patients. Therapeutic hypothermia was used in 51 (41%) patients. The ICU mortality rate was 98/133 (74%). Main causes of ICU death were refractory shock or multiple organ failure (n = 64, 48%) and neurological injury (n = 27, 20%); 42 (32%) patients died in ICU after treatment-limitation decisions. Twenty-four (18%) patients were discharged alive from the hospital. Overall 6-month survival rate was 14% (18/133, 95% confidence interval, 8-21%). Survival rates at ICU discharge and after 6 months did not differ significantly across type of malignancy or between the OHCA and IHCA groups, and neither were they significantly different from those in matched controls who had cardiac arrest but no malignancy. CONCLUSIONS: Even if low, the 6-month survival rate of 14% observed in cancer patients admitted to the ICU after cardiac arrest and ROSC may support the admission of these patients to the ICU and may warrant an initial full-code ICU management.


Asunto(s)
Reanimación Cardiopulmonar/métodos , Unidades de Cuidados Intensivos , Neoplasias/complicaciones , Paro Cardíaco Extrahospitalario/terapia , Anciano , Femenino , Francia/epidemiología , Mortalidad Hospitalaria/tendencias , Humanos , Hipotermia Inducida/métodos , Masculino , Persona de Mediana Edad , Neoplasias/mortalidad , Paro Cardíaco Extrahospitalario/etiología , Paro Cardíaco Extrahospitalario/mortalidad , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Resultado del Tratamiento
11.
Arthritis Rheumatol ; 67(5): 1353-60, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25604824

RESUMEN

OBJECTIVE: Takayasu arteritis (TAK) is a large-vessel vasculitis that induces damage to the aorta and its branches. Glucocorticoids remain the gold standard of therapy for TAK. The nature of the T cells driving vascular inflammation and the effects of glucocorticoids on the systemic components of TAK are not understood. The aim of this study was to analyze T cell homeostasis and cytokine production in peripheral blood and inflammatory lesions of the aorta in patients with TAK. METHODS: T cell homeostasis and cytokine production in peripheral blood and inflammatory lesions of the aorta were analyzed using Luminex analysis, flow cytometry, and immunohistochemical analysis. The study included 41 patients fulfilling the American College of Rheumatology 1990 criteria for the classification of TAK (17 patients with active TAK and 24 patients with disease in remission), 30 patients with giant cell arteritis and 39 patients with Behçet's disease (disease controls), and 20 age- and sex-matched healthy control subjects. RESULTS: We observed a marked increase in the expression of Th1 and Th17 cells, which correlated with TAK disease activity. The addition of serum from patients with active TAK to sorted CD4+ T cells from healthy donors in culture medium induced significant production of interferon-γ (IFNγ) and interleukin-17A (IL-17A). We demonstrated the presence of IFNγ-, IL-6-, and IL-17A-producing T cells in vascular inflammatory infiltrates in patients with TAK. Corticosteroid therapy was associated with decreased levels of circulating Th1 cytokines in corticosteroid-treated patients with TAK compared with steroid-free patients with TAK (for IL-2, mean ± SD 5,079 ± 5,300 versus 7,359 ± 3,197 pg/ml; for IFNγ, 2,592 ± 3,072 versus 8,393 ± 3,392 pg/ml; for tumor necrosis factor α, 847 ± 724 versus 1,491 ± 392 pg/ml). However, glucocorticoids had essentially no effect on the frequency of Th17 cytokines (IL-1 receptor, IL-17, and IL-23). CONCLUSION: The Th17 and Th1 pathways contribute to the systemic and vascular manifestations of TAK. Glucocorticoid treatment suppresses Th1 cytokines but spares Th17 cytokines in patients with TAK.


Asunto(s)
Citocinas/inmunología , Arteritis de Takayasu/inmunología , Células TH1/inmunología , Células Th17/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Síndrome de Behçet/inmunología , Estudios de Casos y Controles , Citocinas/metabolismo , Femenino , Arteritis de Células Gigantes/inmunología , Glucocorticoides/uso terapéutico , Humanos , Inflamación , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-17/inmunología , Interleucina-17/metabolismo , Interleucina-2/inmunología , Interleucina-2/metabolismo , Interleucina-23/inmunología , Interleucina-23/metabolismo , Interleucina-6/inmunología , Interleucina-6/metabolismo , Masculino , Persona de Mediana Edad , Receptores de Interleucina-1/inmunología , Índice de Severidad de la Enfermedad , Arteritis de Takayasu/tratamiento farmacológico , Células TH1/metabolismo , Células Th17/metabolismo , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/metabolismo , Adulto Joven
12.
J Comp Neurol ; 207(1): 99-103, 1982 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-7096642

RESUMEN

It is estimated by means of electron microscopy that the optic nerve of the turtle Pseudemys scripta elegans contains 394,900 fibers of which approximately 80% are myelinated. The total fiber count agrees well with counts obtained from electron microscopic studies on other turtle species. There are, however, differences among these species in the percentage of myelinated fibers in the optic nerve. The axon diameter distribution of the myelinated fibers (excluding myelin) has a mode at 0.87 micrometer while that of the unmyelinated fibers has a mode at 0.42 micrometer. Both distributions are unimodal and are of a similar form in all areas of the nerve sampled. The total fiber count reported here agrees well with previous reports of ganglion cell counts in Pseudemys and the characteristics of the fiber distributions are comparable to those reported for nonreptilian vertebrates.


Asunto(s)
Fibras Nerviosas/ultraestructura , Nervio Óptico/anatomía & histología , Tortugas/anatomía & histología , Animales , Axones/ultraestructura , Microscopía Electrónica , Fibras Nerviosas Mielínicas/ultraestructura , Neuronas/ultraestructura
13.
Vision Res ; 27(8): 1291-8, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3424677

RESUMEN

Intraocular scatter of monochromatic light was assessed in three subjects (ages 21, 38, and 43) using the equivalent veil technique. For an annular stimulus of 3 deg inner and 8 deg outer diameter, the scattered illuminance at the center averaged 1.2% of the surround and was independent of wavelength from 420 to 650 nm. These results are inconsistent with predictions of wavelength dependence inherent in recent theories of ocular scatter. We conclude that intraocular scatter is produced by particles or cellular structures substantially larger than the wavelength of light.


Asunto(s)
Fenómenos Fisiológicos Oculares , Adulto , Femenino , Humanos , Luz , Masculino , Psicofísica , Retina/fisiología , Dispersión de Radiación , Umbral Sensorial/fisiología , Espectrofotometría
14.
Vision Res ; 35(4): 495-506, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7900290

RESUMEN

Similarity ratings were obtained to determine the minimum number of Gabor components that would produce a comparison texture that appeared preattentively similar to a 64-component standard texture. All textures were chosen to be both specifiable by a relatively small number of localized spectral components and sufficiently complex to approximate natural textures. The number of component orientations in the set of comparison textures was found to be a particularly important determinant of texture discrimination in that its effect on rated similarity was largely independent of the total number of components making up the texture. Textures were also presented at 0.75 degree and 20 degrees eccentricity, with the latter magnified by a factor of either 2 or 4. The overall similarity rating did not change with either magnification, whereas the critical number of orientations, defined as the number of orientations above which rated similarity was constant, did change for the higher magnification. The latter finding is consistent with the proposition that higher-order discriminations are mediated by higher cortical areas that integrate information across the visual field. Finally, the phase-bandwidth of a set of coherent textures was also varied in order to determine whether more explicit differences in the spatial structure of stimuli might affect rated similarity. In contrast to the results for component orientation, the ratings, obtained at 0.75 degree and 20 degrees, were different even when the phase-bandwidth stimuli were magnified by a factor of 4.


Asunto(s)
Reconocimiento Visual de Modelos/fisiología , Campos Visuales , Adulto , Sensibilidad de Contraste/fisiología , Discriminación en Psicología/fisiología , Femenino , Humanos , Masculino , Matemática , Rotación
15.
Vision Res ; 28(10): 1145-55, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3257017

RESUMEN

Saccaadic response preferences and latencies were measured using dual targets presented at 5, 10 and 15 deg along the horizontal meridian in either one or both visual hemifields. In the unihemifield condition, subjects exhibited a strong preference (about 95%) in favor of the target presented closer to the original fixation point. Further, the presence of the second target did not increase the response latency to the preferred target. In the bihemifield condition using spatially symmetric targets, directional preference varied across subjects from 57 to 100% (mean = 83%). There was also a significant increase in response latency as compared with responses to either single targets or dual targets presented in one hemifield. This latency increase was observed for responses in both the preferred and nonpreferred directions and was taken as evidence of mutual interaction between the two hemispheres. The response preferences could be eliminated by delaying the onset of the preferred target by about 100 msec in the unihemifield condition and by about 50 msec in the bihemifield condition. Further, the interactions between the effects of the targets on response time in the bihemifield condition were found to be asymmetrical in that a target presented in the preferred hemifield has a greater effect than a target in the nonpreferred hemifield on responses to targets presented in the counterhemifield. The results suggest an asymmetry in hemispheric interaction which has not previously been demonstrated in the visualoculomotor system.


Asunto(s)
Movimientos Oculares , Movimientos Sacádicos , Percepción Visual/fisiología , Adulto , Humanos , Estimulación Luminosa , Factores de Tiempo , Campos Visuales
16.
J Anim Sci ; 68(7): 1922-8, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2384385

RESUMEN

The genetic influence on body and adipose tissue characteristics of newborn pigs and their correlations to growth rate, BW, body length, backfat thickness and adipocyte size in the outer and inner layers of backfat in 8-d-old Large White piglets were determined. Samples of adipose tissue were obtained by biopsy. Pigs were born to 32 sows mated with the same boar. Heritability and genetic correlations were estimated with dam component of variance; therefore, bias due to common environmental effects cannot be excluded. The heritability estimate for adipocyte volume (.89 +/- .28) was higher than that for backfat thickness at the first and last thoracic vertebrae (.50 +/- .22; .63 +/- .24) and for body weight (.59 +/- .23) at 8 d. Backfat thickness was more closely related genetically and phenotypically to body weight and length than to adipose tissue cellularity. Heritability estimates were .75 +/- .28 for gain from 8 d to weaning and from weaning to 95 d (probably because of common environmental effects) but were .31 +/- .20 for ADG from 95 d to slaughter. Characteristics at 8 d were closely correlated phenotypically with growth rate until weaning. These correlations became lower in the two subsequent periods (to 95 d and to slaughter). Corresponding genetic correlations were nonsignificant.


Asunto(s)
Tejido Adiposo/anatomía & histología , Animales Recién Nacidos/crecimiento & desarrollo , Porcinos/crecimiento & desarrollo , Animales , Animales Recién Nacidos/anatomía & histología , Animales Recién Nacidos/genética , Peso Corporal , Femenino , Variación Genética , Análisis de los Mínimos Cuadrados , Masculino , Fenotipo , Caracteres Sexuales , Porcinos/anatomía & histología , Porcinos/genética
17.
J Anim Sci ; 68(7): 1929-35, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2384386

RESUMEN

Backfat thickness, carcass length, area of M. longissimus and carcass composition were determined for 253 Large White barrows and gilts to examine the genetic influence on the main characteristics of the carcass and the correlation of these traits with body measurements and fat characteristics at 8 d of age. Pigs were born to 32 sows mated to the same boar. At the age of 8 d, weight, body length and backfat thickness and cellularity were measured. Pigs were slaughtered at 95 and 145 kg live weight. Heritability and genetic correlations were estimated with dam component of variance. Higher adiposity of carcasses was noted for barrows than for gilts and for those animals slaughtered at the heavier vs at the lighter weight. High h2 values were observed for carcass length (.89 +/- .29), area of the M. longissimus (.67 +/- .26) and backfat thickness at the gluteus medius (.77 +/- .28). Percentage of commercial cuts also had high heritabilities. Phenotypic and genetic correlations between the characteristics at 8 d and backfat thickness, carcass length and M. longissimus area at slaughter were not statistically significant. However, significant phenotypic correlations were found between cellularity of the outer and inner layers at 8 d and percentage of major cuts (e.g., rp = .27 with total fat cuts); cellularity of the outer layer at 8 d also was correlated genetically with carcass composition (e.g., rg = .50 +/- .19 with total fat cuts). Genetic predisposition toward intensive fat deposition was more clearly predicted by cellularity than by thickness of adipose tissue in newborn pigs.


Asunto(s)
Tejido Adiposo/anatomía & histología , Animales Recién Nacidos/anatomía & histología , Peso Corporal , Porcinos/anatomía & histología , Animales , Animales Recién Nacidos/genética , Animales Recién Nacidos/crecimiento & desarrollo , Femenino , Variación Genética , Masculino , Fenotipo , Caracteres Sexuales , Porcinos/genética , Porcinos/crecimiento & desarrollo
18.
J Anim Sci ; 68(7): 1936-43, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2384387

RESUMEN

Genetic and phenotypic relationships between adipose tissue characteristics of 253 piglets aged 8 d and qualitative characteristics of their backfat at 95 and 145 kg live weight were studied. Heritability of these qualitative aspects was estimated as well. Backfat samples were tested for cellularity, moisture, lipid content and fatty acid composition of the outer and inner layers. Adipose cellularity at birth proved to be correlated with cell volume, moisture and total unsaturated fatty acid, C18:0 and C18:2 contents present in backfat at slaughter. Estimates of heritability calculated for the outer layer of backfat indicated that progress can be made by selecting for water content and fatty acid composition. Neonatal cellularity furnishes a useful indicator not only of the backfat cell size at slaughter but also of the chemical factors important in determining the physical and organoleptic characteristics of porcine fat.


Asunto(s)
Tejido Adiposo/anatomía & histología , Animales Recién Nacidos/anatomía & histología , Ácidos Grasos/análisis , Lípidos/análisis , Porcinos/anatomía & histología , Tejido Adiposo/análisis , Animales , Animales Recién Nacidos/genética , Animales Recién Nacidos/crecimiento & desarrollo , Peso Corporal , Femenino , Genotipo , Masculino , Fenotipo , Caracteres Sexuales , Porcinos/genética , Porcinos/crecimiento & desarrollo
19.
Ann Fr Anesth Reanim ; 33(4): e79-81, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24630168

RESUMEN

Ethylene glycol poisoning is rare, but prompt diagnosis is crucial, in order to initiate specific treatments. Herein, we report the case of a patient who was admitted to ICU for coma and extreme metabolic acidosis with unexpected hyperlactatemia on initial ICU blood gas analyzer. Ethylene glycol poisoning was diagnosed, and hyperlactatemia was ruled out on a blood sample sent to the biochemistry department. Interference of blood gas analyzers lactate electrodes with metabolites of ethylene glycol were the source of this apparent hyperlactatemia. Symptoms gradually improved and false hyperlactatemia resolved after renal replacement therapy and fomepizole administration. Time course of ethylene glycol concentration showed similar evolution. After initial confirmation of ethylene glycol presence, this biological interference could thus be used as a surrogate of costly and highly specialised dosages.


Asunto(s)
Glicol de Etileno/envenenamiento , Hiperlactatemia/inducido químicamente , Acidosis Láctica/inducido químicamente , Acidosis Láctica/terapia , Coma/inducido químicamente , Glicol de Etileno/sangre , Personas con Mala Vivienda , Humanos , Hiperlactatemia/sangre , Enfermedades Renales/inducido químicamente , Enfermedades Renales/terapia , Masculino , Persona de Mediana Edad , Terapia de Reemplazo Renal
20.
Ann Fr Anesth Reanim ; 33(2): 98-101, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24361281

RESUMEN

With increasing public education in basic life support and with the widespread use of automated defibrillators, post-cardiac arrest comatose patients represent a growing part of ICU admissions. However the prognosis remains very poor and only a very low proportion of these resuscitated patients will recover and will leave the hospital without major neurological impairments. Neurological dysfunction predominantly includes disorders of consciousness, and may also include other manifestations such as seizures, myoclonus status epilepticus and other forms of movement disorders including post-anoxic myoclonus. In the most severe cases, coma may be irreversible or evolve towards a minimally conscious state, a vegetative state or even brain death. These severe conditions represent by far the leading cause of mortality and disability in such patients. Currently, early use of mild therapeutic hypothermia is the only treatment that demonstrated its ability to decrease neurological consequences and to improve the prognosis. Prognostication outcome is still mainly based on a rigorous clinical evaluation coupled with neuro-physiological investigations, but brain functional imaging could become a valuable tool in the near future. Clinical research focusing on survivors should be strongly encouraged in order to assess the mid- and long-terms outcome of survivors and to evaluate the impact of new treatments or strategies.


Asunto(s)
Daño Encefálico Crónico/etiología , Trastornos de la Conciencia/etiología , Paro Cardíaco/complicaciones , Hipoxia Encefálica/etiología , Daño Encefálico Crónico/fisiopatología , Daño Encefálico Crónico/prevención & control , Daño Encefálico Crónico/psicología , Muerte Encefálica , Reanimación Cardiopulmonar , Cuidados Críticos , Paro Cardíaco/terapia , Humanos , Hipotermia Inducida , Inutilidad Médica/ética , Fármacos Neuroprotectores/uso terapéutico , Pronóstico , Calidad de Vida , Convulsiones/etiología , Estado Epiléptico/etiología , Sobrevivientes , Resultado del Tratamiento
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