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1.
Occup Med (Lond) ; 70(9): 680-684, 2020 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-33247305

RESUMEN

BACKGROUND: The number of patients living with depression continues to increase in Japan. The economic effects of depression include loss of productivity due to both absenteeism and presenteeism. Gender differences have been reported in prevalence, onset pathways and subjective symptoms of depression. AIMS: To understand how workers with major depressive disorder (MDD) perceive problems in the workplace and examine gender differences in their self-perceived levels of functioning at work, noticed during the initial stages of depression. METHODS: This is a cross-sectional study of Japanese workers with MDD. Participants' self-perceived changes in the level of functioning at work were surveyed after the diagnosis during the first visit. The relationship between gender and changes in the level of functioning at work as initially perceived by the participants themselves was analysed using the chi-square test, supplemented by a residual analysis. RESULTS: We administered the survey to 147 workers with MDD. In terms of gender differences in initial self-perceived changes in the level of functioning at work, the proportion of men reporting reduced work efficiency was significantly higher than that of women, while the proportion of women reporting deterioration in relationships with colleagues and superiors was significantly higher than that of men. CONCLUSIONS: The findings suggest that greater attention to reduced work efficiency by men and to deterioration in work relationships by women with MDD should be essential components of self-care. Managers need to pay attention to the level of functioning and provide adequate social support for employees.


Asunto(s)
Depresión , Trastorno Depresivo Mayor , Absentismo , Estudios Transversales , Femenino , Humanos , Japón , Masculino , Caracteres Sexuales , Encuestas y Cuestionarios , Lugar de Trabajo
2.
Sci Rep ; 9(1): 9803, 2019 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-31278289

RESUMEN

The anthropogenic CO2 accumulating in the ocean is lowering seawater carbonate ion concentration and may reduce calcification rates of marine calcareous organisms. Several proxies based on test weights of planktic foraminifera have been used to evaluate the impact of ocean acidification on these organisms. Unfortunately, because of the absence of a method to evaluate the bulk density of a test, the impact of seawater carbonate chemistry on test calcification is still not fully understood. In this study, we measured bulk densities of living Globigerina bulloides (planktic foraminifera) tests with an X-ray micro-computed tomography (XMCT) scanner and compared them with ambient seawater characteristics. Results demonstrated that test bulk densities were controlled by ambient seawater carbonate ion concentrations and that changes of test bulk densities were accompanied by changes in micron to submicron scale porosity of internal ultrastructure. These results suggest that alteration of the bulk density of foraminiferal tests due to acidification of ambient seawater can be directly observed by XMCT scanning. A useful metric of calcification intensity would therefore be physical measurements of test densities with XMCT.


Asunto(s)
Calcificación Fisiológica , Foraminíferos/fisiología , Océanos y Mares , Plancton/fisiología , Agua de Mar/química , Carbonato de Calcio/química , Ciclo del Carbono/fisiología , Dióxido de Carbono/química , Carbonatos/química , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Microtomografía por Rayos X
3.
Occup Med (Lond) ; 69(1): 39-46, 2019 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-30428079

RESUMEN

BACKGROUND: Teaching is one of the most stressful occupations. Over the last decade, about 5000 Japanese public school teachers per year have taken sick leave due to a mental illness. School principals and vice principals also face occupational stress, although few studies have examined occupational stress in these groups. AIMS: To clarify the relationship between occupational stress, role problems and depressive symptoms among school principals and vice principals in Japan. METHODS: We conducted a cross-sectional study in 2013 with data from 262 principals and 268 vice principals in Japan. We used the Japanese version of Zung's Self-Rating Depression Scale (SDS) to evaluate depressive symptoms and the Generic Job Stress Questionnaire to evaluate occupational stress and social support. We categorized SDS scores above 49 as indicating depression. We examined the relationship between depressive symptoms and perceived occupational stress using stepwise forward multivariate logistic regression analyses. RESULTS: Thirty-six (14%) principals and 81 (30%) vice-principals were categorized into the depressive group. Quantitative workload (odds ratio, OR = 6.62 [2.63-16.70]) and role ambiguity (OR = 4.94[1.57-15.53]) were associated with higher depressive scores in principals. Social support from supervisors (OR = 4.14 [1.97-8.68]) and role ambiguity (OR = 9.71 [4.08-23.14]) were associated with higher depressive scores in vice-principals. CONCLUSIONS: Clarifying job roles for principals and vice-principals, reducing quantitative workload for principals and increasing supervisory support for vice-principals may be important for mitigating depression for school principals and vice-principals in Japan.


Asunto(s)
Personal Administrativo/psicología , Depresión/epidemiología , Estrés Laboral/epidemiología , Instituciones Académicas , Estudios Transversales , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Apoyo Social , Encuestas y Cuestionarios , Carga de Trabajo/estadística & datos numéricos
4.
Occup Med (Lond) ; 68(3): 171-176, 2018 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-29506081

RESUMEN

Background: Work-related stressors are associated with low sleep quality. However, few studies have reported an association between role stressors and sleep quality. Aims: To elucidate the association between role stressors (including role conflict and ambiguity) and sleep quality. Methods: Cross-sectional study of daytime workers whose sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). Work-related stressors, including role stressors, were assessed using the Generic Job Stress Questionnaire (GJSQ). The association between sleep quality and work-related stressors was investigated by logistic regression analysis. Results: A total of 243 participants completed questionnaires were received (response rate 71%); 86 participants reported poor sleep quality, based on a global PSQI score ≥6. Multivariable logistic regression analysis revealed that higher role ambiguity was associated with global PSQI scores ≥6, and that role conflict was significantly associated with sleep problems, including sleep disturbance and daytime dysfunction. Conclusions: These results suggest that high role stress is associated with low sleep quality, and that this association should be considered an important determinant of the health of workers.


Asunto(s)
Estrés Laboral/complicaciones , Rol Profesional/psicología , Horario de Trabajo por Turnos/efectos adversos , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estrés Laboral/psicología , Psicometría/instrumentación , Psicometría/métodos , Horario de Trabajo por Turnos/psicología , Trastornos del Sueño-Vigilia/complicaciones , Encuestas y Cuestionarios
5.
J Hosp Infect ; 94(2): 150-3, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27346624

RESUMEN

Inpatients who had been in close contact with patients with influenza were given oseltamivir [75mg capsules once daily for adults or 2mg/kg (maximum of 75mg) once daily for children] for three days as postexposure prophylaxis (PEP). The index patients with influenza were prescribed a neuraminidase inhibitor and were discharged immediately or transferred to isolation rooms. The protective efficacy of oseltamivir for three days was 93% overall [95% confidence interval (CI) 53-99%; P=0.023] and 94% for influenza A (95% CI 61-99%; P=0.017), which is comparable to that of seven- to 10-day regimens of oseltamivir as PEP.


Asunto(s)
Antivirales/administración & dosificación , Quimioprevención/métodos , Gripe Humana/prevención & control , Oseltamivir/administración & dosificación , Profilaxis Posexposición/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
6.
Neuroscience ; 284: 632-642, 2015 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-25450961

RESUMEN

The primary vestibular neurons convey afferent information from hair cells in the inner ear to the vestibular nuclei and the cerebellum. The intrinsic firing properties of vestibular ganglion cells (VGCs) are heterogeneous to sustained membrane depolarization, and undergo marked developmental changes from phasic to tonic types during the early postnatal period. Previous studies have shown that low-voltage-activated potassium channels, Kv1 and Kv7, play a critical role in determining the firing pattern of VGCs. In the present study, we explored the developmental changes in the properties of hyperpolarization-activated current (Ih) in rat VGCs and the role played by Ih in determining the firing properties of VGCs. Tonic firing VGCs showed a larger current density of Ih as compared to phasic firing VGCs, and tonic firing VGCs became phasic firing in the presence of ZD7288, an Ih channel blocker, indicating that Ih contributes to control the firing pattern of VGCs. The amplitude of Ih increased and the activation kinetics of Ih became faster during the developmental period. Analysis of developmental changes in the expression of hyperpolarization-activated cyclic nucleotide-gated cation (HCN) channels revealed that expression of HCN1 protein and its mRNA increased during the developmental period, whereas expression of HCN2-4 protein and its mRNA did not change. Our results suggest that HCN1 channels as well as Kv1 channels are critical in determining the firing pattern of rat VGCs and that developmental up-regulation of HCN1 transforms VGCs from phasic to tonic firing phenotypes.


Asunto(s)
Potenciales de Acción/fisiología , Ganglios Sensoriales/crecimiento & desarrollo , Neuronas/fisiología , Nervio Vestibular/crecimiento & desarrollo , Potenciales de Acción/efectos de los fármacos , Animales , Western Blotting , Células Cultivadas , Ganglios Sensoriales/efectos de los fármacos , Ganglios Sensoriales/fisiología , Regulación del Desarrollo de la Expresión Génica , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/metabolismo , Neuronas/efectos de los fármacos , Neurotransmisores/farmacología , Técnicas de Placa-Clamp , Canales de Potasio/metabolismo , Pirimidinas/farmacología , ARN Mensajero/metabolismo , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Nervio Vestibular/efectos de los fármacos , Nervio Vestibular/fisiología
8.
AJNR Am J Neuroradiol ; 33(11): 2167-70, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22595898

RESUMEN

BACKGROUND AND PURPOSE: Restenosis after CAS is a postoperative problem, with a reported frequency of approximately 2%-8%. However differences in stent design, procedure, and the antiplatelet agent appear to affect the incidence of restenosis. We assessed the frequency of restenosis and the effect of the antiplatelet agent CLZ in preventing restenosis after CAS by the standard procedure using the CWS. MATERIALS AND METHODS: Between May 2010 and October 2011, 62 lesions in 60 consecutive patients underwent CAS using the CWS at 4 medical institutions, and all patients were followed clinically and assessed by sonography, 3D-CTA, or angiography at 3 and 6 months postoperatively. Restenosis was defined as ≥50% stenosis. The incidence of restenosis and the variation in the incidence of restenosis by the difference in type of antiplatelet agent between the CLZ group (n = 30; aspirin, 100 mg, and CLZ, 200 mg) and the non-CLZ group (n = 32; aspirin, 100 mg, and clopidogrel, 75 mg [n = 29]; or ticlopidine, 100 mg [n = 2] or 200 mg [n = 1]) were retrospectively investigated. Two antiplatelet agents were given starting 1 week preoperatively until at least 3 months postoperatively. RESULTS: Restenosis occurred in 5 patients (8.3%), but all were cases of asymptomatic lesions in the follow-up period. All 5 patients with restenosis were in the non-CLZ group, with no cases of restenosis in the CLZ group; the difference was significant (P = .0239). CONCLUSIONS: The restenosis rate after CAS by using the CWS was 8.3%. CLZ was associated with significant inhibition of restenosis.


Asunto(s)
Enfermedades de las Arterias Carótidas/cirugía , Oclusión de Injerto Vascular/etiología , Oclusión de Injerto Vascular/prevención & control , Premedicación/métodos , Stents/efectos adversos , Tetrazoles/administración & dosificación , Anciano , Anciano de 80 o más Años , Enfermedades de las Arterias Carótidas/complicaciones , Cilostazol , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Estudios Retrospectivos , Resultado del Tratamiento , Vasodilatadores/administración & dosificación
9.
Bone Marrow Transplant ; 45(5): 912-8, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19802024

RESUMEN

Chronic GVHD (cGVHD) of the liver is an important cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-SCT). It is characterized by the destruction of bile duct epithelium followed by progressive cholestasis, which resembles primary biliary cirrhosis (PBC) clinically and histologically. Bezafibrate (BF) is a widely used agent for hyperlipidemia that is also effective in ursodeoxycholic acid (UDCA)-resistant PBC patients. The putative mechanism in cholestasis is that BF upregulates the expression of phosphatidylcholine flippase on bile canaliculi, facilitates phospholipid output into bile and relieves bile duct damage caused by hydrophobic bile salts. Therefore, the effects of BF in patients with cGVHD of the liver were investigated. Of 87 patients with cGVHD who survived more than 100 days after SCT, 8 were given BF to treat liver cGVHD because of a poor therapeutic response to UDCA and immunosuppressants. The serum alkaline phosphatase (ALP) and gamma-glutamyl transpeptidase (gamma-GTP) levels decreased significantly within 1 month after initiation of BF therapy compared with those before BF therapy in all patients (ALP, 964.9.0+/-306.9 to 597.8+/-102.5 IU/l, P=0.012; gamma-GTP, 528.8+/-299.0 to 269.0+/-119.9 IU/l, P=0.012). BF was effective in patients with liver cGVHD, including UDCA-resistant patients. BF could be a novel therapeutic option for liver cGVHD that helps to preserve normal immunity with the antileukemic effect of cGVHD.


Asunto(s)
Bezafibrato/uso terapéutico , Enfermedad Injerto contra Huésped/terapia , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Hepatopatías/terapia , Adulto , Enfermedad Crónica , Femenino , Enfermedad Injerto contra Huésped/complicaciones , Enfermedad Injerto contra Huésped/diagnóstico , Humanos , Hepatopatías/complicaciones , Hepatopatías/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Trasplante Homólogo
10.
Clin Genet ; 76(4): 383-91, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19737284

RESUMEN

Usher syndrome (USH) is an autosomal recessive disorder characterized by retinitis pigmentosa and hearing loss. USH type 2 (USH2) is the most common type of USH and is frequently caused by mutations in USH2A, which accounts for 74-90% of USH2 cases. This is the first study reporting the results of scanning for USH2A mutations in Japanese patients with USH2. In 8 of 10 unrelated patients, we identified 14 different mutations. Of these mutations, 11 were novel. Although the mutation spectrum that we identified differed from that for Caucasians, the incidence of mutations in USH2A was 80% for all patients tested, which is consistent with previous findings. Further, c.8559-2A>G was identified in four patients and accounted for 26.7% of mutated alleles; it is thus a frequent mutation in Japanese patients. Hence, mutation screening for c.8559-2A>G in USH2A may prove very effective for the early diagnosis of USH2.


Asunto(s)
Proteínas de la Matriz Extracelular/genética , Predisposición Genética a la Enfermedad/genética , Mutación/genética , Síndromes de Usher/genética , Adulto , Pueblo Asiatico , Análisis Mutacional de ADN , Cartilla de ADN/genética , Femenino , Pruebas Genéticas , Humanos , Japón , Masculino , Persona de Mediana Edad
11.
Ann N Y Acad Sci ; 1164: 344-6, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19645924

RESUMEN

Bone-conducted vibration of the forehead, in the midline at the hairline (Fz) causes linear acceleration stimulation of both mastoids and results in an ocular vestibular-evoked myogenic potential (oVEMP), recorded by surface electromyogram (EMG) electrodes just beneath the eyes. The early n10 component of the oVEMP is symmetrical in healthy subjects, absent in patients with bilateral vestibular loss, and in patients after unilateral vestibular loss (uVL) n10 is small or absent on the side contralateral to the uVL, but of normal amplitude on the side contralateral to the healthy ear. The n10 component probably reflects mainly otolithic function, since in the guinea pig, primary otolith irregular neurons are selectively activated by bone-conducted vibration (BCV) at low intensities (0.1 g), whereas semicircular canal primary afferents are not activated even at high intensities (10 g).


Asunto(s)
Huesos/fisiología , Membrana Otolítica/fisiología , Humanos , Vibración
12.
Clin Neurophysiol ; 120(3): 588-93, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19211301

RESUMEN

OBJECTIVE: The n10 component (n10) of the ocular vestibular evoked myogenic potential (oVEMP) to brief bone conducted vibration (BCV) of the forehead at Fz is probably caused by the vibration selectively activating vestibular otolithic receptors. If the n10 is due primarily to utricular activation then diseases which affect only the superior division of the vestibular nerve (SVN) should reduce or eliminate n10. METHODS: The n10 component of the oVEMP was measured in 13 patients with unilateral SVN but with inferior vestibular nerve function preserved. RESULTS: We compared the n10 to BCV of these 13 SVN patients to previously published data for healthy subjects and patients after complete unilateral vestibular loss. We found that in 12 out of the 13 patients with SVN, n10 was markedly reduced or absent under the contralesional eye. CONCLUSION: Since all utricular afferents course in the superior vestibular nerve and in 12/13 of these patients the n10 was reduced we conclude that the n10 component of the oVEMP to BCV is probably mediated by the superior vestibular nerve and probably due to activation of mainly utricular receptors. SIGNIFICANCE: The n10 appears to be a simple new test of superior vestibular nerve and probably mainly utricular function.


Asunto(s)
Conducción Ósea/fisiología , Potenciales Evocados/fisiología , Músculos del Cuello/fisiología , Músculos Oculomotores/fisiología , Reflejo Vestibuloocular/fisiología , Nervio Vestibular/fisiología , Adulto , Anciano , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Persona de Mediana Edad , Músculos Oculomotores/inervación , Membrana Otolítica/fisiología , Estimulación Física , Sáculo y Utrículo/fisiología , Vestíbulo del Laberinto/fisiología , Vibración
14.
Clin Neurophysiol ; 119(9): 2135-47, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18639490

RESUMEN

OBJECTIVE: To provide the empirical basis for using ocular vestibular evoked myogenic potentials (oVEMPS) in response to Fz bone conducted vibration (BCV) stimulation to indicate vestibular function in human subjects. To show the generality of the response by testing a large number of unselected healthy subjects across a wide age range and the repeatability of the response within subjects. To provide evidence that the response depends on otolithic function. METHODS: The early negative component (n10) of the oVEMP to brief BCV of the forehead, in the midline at the hairline (Fz) is recorded by surface EMG electrodes just beneath the eyes. We used a Bruel and Kjaer 4810 Mini-Shaker or a light tap with a tendon hammer to provide adequate BCV stimuli to test a large number (67) of unselected healthy people to quantify the individual differences in n10 magnitude, latency and symmetry to Fz BCV. A Radioear B-71 bone oscillator at Fz is not adequate to elicit a reliable n10 response. RESULTS: The n10 oVEMP response showed substantial differences in amplitude between subjects, but is repeatable within subjects. n10 is of equal magnitude in both eyes with an average asymmetry around 11%. The average n10 amplitude for Mini Tone Burst BCV is 8.47microV+/-4.02 (sd), the average latency is 10.35ms+/-0.63 (sd). The amplitude of n10 decreases and its latency increases with age. CONCLUSIONS: oVEMPs are a new reliable, repeatable test to indicate vestibular and probably otolithic function. SIGNIFICANCE: This study shows the optimum conditions for recording oVEMPs and provides baseline values for individual differences and asymmetry. oVEMPs can be measured in senior subjects without difficulty.


Asunto(s)
Conducción Ósea/fisiología , Potenciales Evocados Auditivos/fisiología , Músculos Oculomotores/fisiología , Prosencéfalo/fisiología , Vibración , Estimulación Acústica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Electromiografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculos Oculomotores/inervación , Tiempo de Reacción/fisiología , Sonido , Enfermedades Vestibulares/fisiopatología
15.
Audiol Neurootol ; 13(6): 396-404, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18663292

RESUMEN

If a patient, who is lying supine and looking upward, is given bone-conducted vibration (BCV) of the forehead at the hairline in the midline (Fz) with a clinical reflex hammer or a powerful bone conduction vibrator, short-latency surface potentials called ocular vestibular evoked myogenic potentials (oVEMP) can be recorded from just beneath the eyes. The early negative (excitatory) component (n10) is approximately equal in amplitude for both eyes in healthy subjects, but in patients with unilateral vestibular loss, the n10 component is significantly asymmetrical under the 2 eyes - the n10 component is small or absent under the eye on the side contralateral to the prior unilateral vestibular nerve removal, but of normal amplitude under the eye on the side contralateral to the healthy ear. The n10 component of the oVEMP response to BCV at Fz stimuli reflects vestibular and probably mainly otolithic function via crossed otolithic-ocular pathways, and so n10 asymmetry is a new way of identifying the affected side in patients with unilateral otolithic loss.


Asunto(s)
Electromiografía/métodos , Frente/fisiología , Membrana Otolítica/fisiopatología , Enfermedades Vestibulares/diagnóstico , Enfermedades Vestibulares/fisiopatología , Adulto , Conducción Ósea , Potenciales Evocados , Femenino , Frente/inervación , Lateralidad Funcional , Humanos , Masculino , Persona de Mediana Edad , Neuroma Acústico/fisiopatología , Neuroma Acústico/cirugía , Tiempo de Reacción , Nervio Vestibular/fisiología , Nervio Vestibular/cirugía , Vibración
16.
Appl Radiat Isot ; 66(10): 1321-4, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18467114

RESUMEN

The excitation function for the (63)Cu(n,p)(63)Ni reaction has been measured by activation method using the 4.5 MV Dynamitron accelerator of the Fast Neutron Laboratory of Tohoku University. Copper plates and hollow spherical copper shells were irradiated by neutrons of various energy up to 14.9 MeV produced by the T(p,n), D(d,n), and T(d,n) reactions. The (63)Ni produced in the irradiated copper target was chemically separated. The beta-rays emitted from the extracted (63)Ni were measured by a liquid scintillation method. The cross sections obtained were compared with the evaluated data files of JENDL-3.3, ENDF/B-VI and FENDL/A-2.0. Consequently, it is found that FENDL/A-2.0 is consistent with our experimental data in the energy range studied in this work. The effect of proton shell appeared in the excitation function obtained is also discussed.


Asunto(s)
Cobre/química , Cobre/efectos de la radiación , Transferencia Lineal de Energía , Neutrones , Níquel/química , Níquel/efectos de la radiación , Radioisótopos/química , Radioisótopos/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Dosis de Radiación
17.
Radiat Environ Biophys ; 47(3): 343-8, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18496703

RESUMEN

The upper and lower limits of the excitation function of the (63)Cu(n,p)(63)Ni reaction were experimentally determined, and the number of (63)Ni nuclei produced in copper samples exposed to atomic bomb neutrons in Hiroshima was estimated by using the experimental excitation functions and the neutron fluences given in the DS02 dosimetry system. The estimated number of (63)Ni nuclei was compared with that measured and with that calculated using the DS02 dosimetry system and the corresponding ENDF/B-VI cross section. In comparison with DS02, there is about a 60% maximum difference in (63)Ni production at the hypocenter when the experimental upper cross section values are used. The difference becomes smaller at greater distances from the hypocenter and decreases, for example, to less than 30 and 5% when using the upper and lower experimental cross sections at 1,000 m, respectively.


Asunto(s)
Cobre/análisis , Neutrones , Níquel/análisis , Guerra Nuclear , Radioisótopos/análisis , Japón
18.
AJNR Am J Neuroradiol ; 29(7): 1329-34, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18451088

RESUMEN

BACKGROUND AND PURPOSE: Visual field defects sometimes occur after temporal resection surgery. Our purpose was to evaluate the correlation between visual field defects caused by temporal lobe resection and the degree of resection of the Meyer loop, as assessed by diffusion tensor tractography. MATERIALS AND METHODS: We examined 14 patients who underwent temporal resection for temporal lobe epilepsy. We obtained presurgical tractographies and then measured the distance between the temporal tip and the anterior limit of the Meyer loop (T-M distance). The degree of resection of the Meyer loop was defined as the distance from the anterior limit of the Meyer loop to the posterior limit of the temporal lobe resection (M-R distance). This was calculated by subtracting the T-M distance from the measured distance between the temporal tip and the posterior limit of the resection (T-R distance). RESULTS: The mean T-M distance was 36.6 mm. The interindividual variation of the distance ranged from 30.0 to 43.2 mm. Although there was no statistically significant correlation between the extent of the visual field defect and the T-R distance, there was a statistically significant correlation between the degree of the visual field defect and the M-R distance. CONCLUSION: The range of interindividual variation for the position of the Meyer loop was rather large, indicating that this variation is the key factor in visual field defects after temporal lobectomy, and the visual field defect appears to be predicted by presurgical tractography. Evaluation of the Meyer loop through the use of tractography seems to be a feasible method, which can be used to predict the visual field defect after temporal lobe resection.


Asunto(s)
Lobectomía Temporal Anterior/métodos , Imagen de Difusión por Resonancia Magnética , Epilepsia del Lóbulo Temporal/cirugía , Aumento de la Imagen , Procesamiento de Imagen Asistido por Computador , Complicaciones Posoperatorias/diagnóstico , Campos Visuales/fisiología , Vías Visuales/lesiones , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Estudios Retrospectivos , Esclerosis/patología , Esclerosis/cirugía , Lóbulo Temporal/patología , Vías Visuales/patología
20.
Eur J Anaesthesiol ; 25(1): 67-71, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17888193

RESUMEN

BACKGROUND AND OBJECTIVE: The alpha-2 adrenergic agonists clonidine and dexmedetomidine are used as an antihypertensive and a sedative, respectively. The aim of this study was to determine the effects of these agonists on ovalbumin-sensitized airway tone in guinea pigs. METHODS: The animals were divided into two groups: control and sensitized. The sensitized group received ovalbumin intraperitoneally and was boosted by exposure to aerosolized ovalbumin. The effects of the alpha-2 agonists were investigated by measuring (1) total lung resistance and (2) smooth muscle tension using a tracheal ring preparation. RESULTS: In the control group, acetylcholine significantly increased total lung resistance in a dose-dependent manner. In the sensitized animals, total lung resistance was significantly higher (by 95%) at 6 mug kg-1 acetylcholine than that in the control group. Both clonidine and dexmedetomidine had a slight but significant inhibitory effect on the response curve of lung resistance at higher concentrations of carbachol, a potent muscarinic receptor agonist. Similar to the data obtained in the control group, both clonidine and dexmedetomidine significantly decreased total lung resistance and the inhibitory effects of these alpha-2 agonists on lung resistance were significantly distinguishable. Similar direct inhibitory effects of the alpha-2 agonists on carbachol-induced muscle contraction were observed in both the control and sensitized groups, the inhibitory effects in the sensitized group being significantly greater. CONCLUSION: Both clonidine and dexmedetomidine can relax the airway even in the hyper-reactive state.


Asunto(s)
Agonistas alfa-Adrenérgicos/uso terapéutico , Obstrucción de las Vías Aéreas/prevención & control , Clonidina/uso terapéutico , Dexmedetomidina/uso terapéutico , Ovalbúmina/efectos adversos , Acetilcolina/farmacología , Obstrucción de las Vías Aéreas/inducido químicamente , Animales , Hiperreactividad Bronquial/inducido químicamente , Hiperreactividad Bronquial/prevención & control , Carbacol/farmacología , Cobayas , Hipnóticos y Sedantes/uso terapéutico , Pulmón/efectos de los fármacos , Pulmón/fisiología , Pulmón/fisiopatología , Masculino , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiología , Organismos Libres de Patógenos Específicos , Tráquea/efectos de los fármacos , Tráquea/fisiología
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