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1.
Rhinology ; 58(2): 136-144, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31904030

RESUMEN

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a heterogeneous disease, and its pathogenesis remains controversial. This study aimed to examine the involvement of fungi in CRSwNP pathogenesis. METHODS: We enrolled 29 controls and 111 CRSwNP patients. We analyzed fungi in the nasal secretions, serum fungus-specific immunoglobulin E (IgE) levels, and nasal polyp (NP) IgE levels. Moreover, we evaluated the correlation between patients' IgE levels and computed tomography (CT) scores. RESULTS: There was no difference in fungal detection rate between CRSwNP patients with and without asthma. Specific IgEs against various antigens were highly detectable in NPs of CRSwNP patients. In CRSwNP patients, fungus-specific IgE levels in NPs were correlated with CT scores. Serum fungus-specific IgEs became undetectable after operation in more than half of the CRSwNP patients without asthma but not in those with asthma. Other serum airborne antigen-specific IgEs did not become undetectable after operation. CONCLUSIONS: Fungus-specific IgEs were highly detectable in NPs of CRSwNP patients, and NPs comprised a major region of specific IgE production. Fungi may therefore play an important role in CRSwNP pathogenesis by inducing Th2 immune responses, including IgE synthesis.


Asunto(s)
Anticuerpos Antifúngicos/inmunología , Inmunoglobulina E/inmunología , Micosis/inmunología , Pólipos Nasales/inmunología , Rinitis/inmunología , Sinusitis/inmunología , Estudios de Casos y Controles , Enfermedad Crónica , Hongos , Humanos , Micosis/complicaciones , Pólipos Nasales/microbiología , Rinitis/microbiología , Sinusitis/microbiología
2.
Lett Appl Microbiol ; 68(6): 589-596, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30942912

RESUMEN

Industrialization often causes polycyclic aromatic hydrocarbon (PAH) and heavy metal contamination of soil and water. In this study, we isolated a bacterium from bottom mud water around a park of Kawasaki Port, Japan, that degrades the 5-ring PAH dibenz[a,h]anthracene (DBA). The strain, Comamonas sp. 3ah48, degraded 29% of DBA (30 µg ml-1 ) in 7 days, and the degradation level increased drastically, to 59%, by the addition of glutamate to the medium. The strain also degraded 40, 14, 15 and 19% of pyrene (Pyr), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF) and benzo[g,h,i]perylene (BghiP) respectively. Benzo[a]pyrene (BaP) was degraded only when glutamate was added to the medium. Strain 3ah48 retained its degradation levels in the presence of 2 mmol l-1 Co2+ , Zn2+ or Cr2+ , at almost the same level as that without metal, and increased the DBA degradation level to 57% in the presence of 2 mmol l-1 Cu2+ , suggesting the possibility of the presence of laccase. SIGNIFICANCE AND IMPACT OF THE STUDY: Sixteen polycyclic aromatic hydrocarbons (PAHs) are listed as priority pollutants by the United States Environmental Protection Agency (USEPA). Information about the biodegradation of one of those PAHs, dibenz[a,h]anthracene (DBA), is limited. The present study focuses on DBA degradation by Comamonas sp. 3ah48 strain isolated around Kawasaki Port, Japan. Comamonas sp. 3ah48, cultured with the addition of glutamate to the medium, was found to increase the degradation level of DBA and to degrade DBA even in the presence of high concentrations of heavy metals.


Asunto(s)
Benzo(a)Antracenos/metabolismo , Benzo(a)pireno/metabolismo , Biodegradación Ambiental , Comamonas/metabolismo , Metales Pesados/toxicidad , Comamonas/efectos de los fármacos , Sedimentos Geológicos/microbiología , Ácido Glutámico/metabolismo , Japón , Hidrocarburos Policíclicos Aromáticos/metabolismo , Suelo/química , Microbiología del Suelo
3.
J Microsc ; 229(Pt 2): 320-6, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18304092

RESUMEN

Properties of evanescent-field-coupled waveguide-mode sensors consisting of a multi-layer structure made of a SiO(2) waveguide, a thin metal layer (Au, Cu, W or Ti), and a high refractive index glass substrate illuminated under the Kretschmann configuration have been theoretically and experimentally investigated. In all cases, reflectivity changes attributed to streptavidin combining to biotinyl groups were observed in close spectral vicinity of the waveguide resonances. The sensors with the Au and the Cu layers show superior sensitivity as compared to those with the W and the Ti layers, whereas the W and Ti layers show better thermal and chemical stability. The results indicate that the materials of thin metal layers should be chosen in accordance with the purpose of sensors and/or environment in which the sensors are used.


Asunto(s)
Técnicas Biosensibles/métodos , Biotina/química , Nanopartículas del Metal/química , Nanotecnología/métodos , Refractometría/métodos , Estreptavidina/química , Óptica y Fotónica , Dióxido de Silicio
4.
Neonatology ; 91(4): 275-80, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17565227

RESUMEN

BACKGROUND/OBJECTIVE: The skin color of newborn infants is subjectively observed to change, depending upon their gestational age. We evaluated the relationship between neonatal skin color and gestational age by employing an objective method. METHODS: Using a tristimulus photocolorimeter, L*, a*, and b* were examined as the parameters of skin color in Japanese newborn infants (Commission Internationale de l'Eclairage L*a*b* color space). The following items were examined: (1) the reproducibility of the measurements; (2) the time course of the values during the first 24 h after birth, and (3) the relationship with the gestational age. The gestational age of these infants had been determined by measuring their crown-rump length during fetal periods. RESULTS: Reliability and validity of the measurements were satisfactory for all parameters. However, a* and b* fluctuated widely during the first 24 h. By contrast, L* was stable between 3 and 24 h after birth. L* measured during these periods directly correlated with the gestational age (r=0.843, p<0.0001). CONCLUSIONS: Because L* represents lightness or darkness, our results suggest that the skin color changes from black to white with maturation. L* may be a helpful parameter for the evaluation of the gestational age of newborn infants.


Asunto(s)
Pueblo Asiatico , Pigmentación de la Piel/fisiología , Piel/crecimiento & desarrollo , Bilirrubina/sangre , Peso al Nacer , Femenino , Edad Gestacional , Hemoglobinas/metabolismo , Humanos , Recién Nacido , Japón , Masculino , Variaciones Dependientes del Observador , Oxígeno/sangre , Reproducibilidad de los Resultados
5.
J Phys Condens Matter ; 18(26): 6009-16, 2006 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-21690815

RESUMEN

Hafnium and zirconium silicate films were deposited on a silicon substrate and the effects of postannealing on their electrical properties were investigated. When the films are postannealed in nitrogen monoxide (NO), the leakage current becomes lower by more than one order of magnitude as compared with that of the as-deposited films. The capacitance-voltage (C-V) hysteresis width is also decreased drastically by the NO postannealing. From electron spin resonance spectroscopy, it is indicated that paramagnetic defects at the interface between the film and the substrate are responsible for the leakage current and the C-V hysteresis. It is also indicated by x-ray photoelectron spectroscopy that the postnitridation effectively terminates these interface defects and contributes to the improvement in electrical properties.

6.
Arerugi ; 50(8): 689-92, 2001 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-11579520

RESUMEN

The treatment points and score for definition of the asthma severity were initially introduced in the guideline for pediatric asthma treatment and management on 1998. We studied the relationship between the severity of clinical symptoms for children with bronchial asthma and the treatment points from July 1998 to November 1999 in our hospital. One hundred twenty five patients (one to 15 years of age, 77 boys and 48 girls) were retrospectively investigated. The treatment points and scores were associated with the clinical symptom score. However, there was no relationship in some patients. In order to define the severity of bronchial asthma, we should investigate not only the severity in terms of the clinical symptoms; the number and degree of asthma attacks, but also the treatment points and score. Furthermore, we should pay attention to the seasonal variation of the treatment points.


Asunto(s)
Asma/fisiopatología , Índice de Severidad de la Enfermedad , Adolescente , Asma/tratamiento farmacológico , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos
7.
Genes Cells ; 6(5): 411-20, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11380619

RESUMEN

BACKGROUND: Group I introns share a conserved core region consisting of two domains, P8-P3-P7 and P4-P6, joined by four base-triples. We showed previously that the T4 td intron can perform phosphoester transfer reactions at two splice sites in the absence of both P4-P6 and the conserved base-triples, whereas it is barely able to perform the intact splicing reaction due to the difficulty of conducting the sequential reactions. RESULTS: Based on previous findings, we constructed a bimolecular ribozyme lacking a large portion of P4-P6 and the base-triples from the Tetrahymena intron, on the assumption that the long-range interactions of the peripheral regions in the two RNAs can compensate for the deteriorated core. The bimolecular ribozyme performed the intact splicing reaction. CONCLUSION: The present analysis indicates that the base-triples are nonessential, but that L4 and the distal part of P4 in P4-P6 are important for conducting the splicing reaction. The reconstituted self-splicing ribozyme provides an amenable system for analysing the role(s) of elements in the core region in the self-splicing reaction mechanism.


Asunto(s)
Intrones/genética , Empalme del ARN , ARN Catalítico/genética , ARN Protozoario/química , ARN Protozoario/metabolismo , ARN Ribosómico/química , Tetrahymena/genética , Animales , Secuencia de Bases , Sitios de Unión , Dominio Catalítico/genética , Secuencia Conservada , Electroforesis en Gel de Poliacrilamida , Cinética , Mutagénesis Sitio-Dirigida , Conformación de Ácido Nucleico , Reacción en Cadena de la Polimerasa , Precursores del ARN/genética , ARN Catalítico/química , ARN Catalítico/metabolismo , ARN Mensajero/química , ARN Mensajero/genética , ARN Protozoario/genética , ARN Ribosómico/genética , Relación Estructura-Actividad
9.
FEBS Lett ; 493(2-3): 95-100, 2001 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-11287003

RESUMEN

The Tetrahymena group I ribozyme requires a hierarchical folding process to form its correct three-dimensional structure. Ribozyme activity depends on the catalytic core consisting of two domains, P4-P6 and P3-P7, connected by a triple-helical scaffold. The folding proceeds in the following order: (i) fast folding of the P4-P6 domain, (ii) slow folding of the P3-P7 domain, and (iii) structure rearrangement to form the active ribozyme structure. The third step is believed to directly determine the conformation of the active catalytic domain, but as yet the precise mechanisms remain to be elucidated. To investigate the folding kinetics of this step, we analyzed mutant ribozymes having base substitution(s) in the triple-helical scaffold and found that disruption of the scaffold at A105G results in modest slowing of the P3-P7 folding (1.9-fold) and acceleration of step (iii) by 5.9-fold. These results suggest that disruption or destabilization of the scaffold is a normal component in the formation process of the active structure of the wild type ribozyme.


Asunto(s)
ARN Catalítico/química , ARN Protozoario/química , Tetrahymena/enzimología , Animales , Secuencia de Bases , Dominio Catalítico , Cartilla de ADN/genética , Cinética , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Conformación de Ácido Nucleico , ARN Catalítico/genética , ARN Protozoario/genética , Tetrahymena/genética
10.
Biol Neonate ; 79(1): 34-8, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11150828

RESUMEN

We measured the levels of type IV collagen and lipid peroxides in bronchoalveolar lavage fluid (BALF) from infants with respiratory distress syndrome (RDS) to determine the relationship to the development of bronchopulmonary dysplasia (BPD). We analyzed their levels between two groups, RDS infants who developed BPD (n = 8, BPD group) and those who did not (n = 11, RDS group). The levels of the type IV collagen in the BPD group were significantly higher than those in the RDS group at 3 and 7 days of age (p = 0.0024). In the BPD group, persistently increased levels of the type IV collagen were observed during the period up to 14 days of age. There was a positive relationship between the type IV collagen levels and polymorphonuclear leukocyte counts, and thiobarbituric acid-reactive substance levels in BALF. These results suggest that the increased type IV collagen levels in BALF of BPD infants may reflect pulmonary basement membrane damage and the involvement of oxygen metabolites in its process.


Asunto(s)
Líquido del Lavado Bronquioalveolar/química , Displasia Broncopulmonar/metabolismo , Colágeno/análisis , Recien Nacido Prematuro , Peso al Nacer , Líquido del Lavado Bronquioalveolar/citología , Edad Gestacional , Humanos , Recién Nacido , Recuento de Leucocitos , Neutrófilos , Respiración Artificial , Síndrome de Dificultad Respiratoria del Recién Nacido/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis
11.
Pediatr Diabetes ; 2(4): 160-9, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15016181

RESUMEN

The Japanese Study Group of Insulin Therapy for Childhood and Adolescent Diabetes (JSGIT) was established in July 1994 with the chief aim to improve the quality of therapy for type 1 diabetes in children, an entity far less common in Japan than in Europe. We proposed four initial research topics: (i) to determine the current status of medical care and glycemic control in Japanese children with type 1 diabetes mellitus; (ii) to standardize the measurement of hemoglobin A1c; (iii) to establish a registry of a large cohort of patients in order to enable prospective studies to improve the quality of therapy for children with type 1 diabetes in Japan; and (iv) to enable participants of the JSGIT to hold a workshop twice annually. We registered a total of 736 patients from 45 hospitals throughout Japan. Intervention via insulin treatment was instituted after 2 yr for those patients whose hemoglobin A1c level was more than 8.1%. The proportion of patients receiving multiple insulin injections increased after intervention; however, average hemoglobin A1c in females remained significantly higher than in males. We identified two forms of diabetes in Japanese children: a rapidly progressive form and a more slowly progressive form. There was a significantly higher prevalence of a family history of diabetes in first-degree relatives in the slowly progressive form. These preliminary findings are the result of the first collaborative study of childhood diabetes in Japan.

12.
Acta Paediatr ; 89(11): 1381-4, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11106054

RESUMEN

To assess the ability of ultrasonography to detect the tip of a very thin (0.4 mm outer diameter) percutaneous central venous catheter (PCVC) in neonates, the PCVC tip location was assessed by ultrasonography (US) and compared to the location estimated by standard radiography for 57 PCVCs in 44 neonates. Of 57 occasions, the examiner could not find the PCVC tip in three cases (5%). In the remaining 54 instances, in 87% of cases, the PCVC tip position was consistent with the location implied by skeletal landmarks on standard radiographs. On 24 occasions we also assessed catheter tip dislodgement according to flexion and extension of the infant's arm. US could detect 78% of cases of catheter tip dislodgement. The PCVC tip was sometimes visualized as a dot and parallel lines as well as mere parallel lines. In a large population of cases, US is a reliable method for detection of a thin PCVC tip. US provides precise information about the PCVC tip position in relation to vascular structure and contributes to safer positioning of the PCVC than traditional radiography alone.


Asunto(s)
Cateterismo Venoso Central , Recién Nacido , Ultrasonografía , Factores de Edad , Migración de Cuerpo Extraño/diagnóstico por imagen , Atrios Cardíacos/diagnóstico por imagen , Humanos , Vena Ilíaca/diagnóstico por imagen , Radiografía , Vena Subclavia/diagnóstico por imagen , Vena Cava Inferior/diagnóstico por imagen , Vena Cava Superior/diagnóstico por imagen
14.
Angew Chem Int Ed Engl ; 39(17): 3120-3122, 2000 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11028052
15.
Opt Lett ; 25(2): 88-9, 2000 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-18059791

RESUMEN

We report the fabrication of long-period optical fiber gratings by use of a refractive-index increase induced by ion implantation. Helium ions were implanted in an optical fiber core through a metal mask that had a 170-microm -pitch grating with spacing of 60 microm . We obtained a wavelength-dependent effective transmission loss by use of the grating.

16.
J Neurophysiol ; 82(6): 3580-5, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10601484

RESUMEN

In contrast to findings in the cat, it recently has been shown that disynaptic pyramidal EPSPs only rarely are observed in forelimb motoneurons of the macaque monkey in the intact spinal cord or after a corticospinal transection in C(5). This finding has been taken to indicate that the disynaptic pyramidal excitatory pathway via C(3)-C(4) propriospinal neurons (PNs) is weakened through phylogeny when the monosynaptic cortico-motoneuronal connection has been strengthened. We reinvestigate this issue with special focus on the possibility that the inhibitory control of the C(3)-C(4) PNs may be stronger in the macaque monkey than in the cat. The effect in forelimb motoneurons of electrical stimulation in the contralateral pyramid was investigated in anesthetized macaque monkeys (Macaca fuscata). We confirmed the low frequency of disynaptic pyramidal EPSPs in forelimb motoneurons. However, after intravenous injection of strychnine, disynaptic EPSPs could be evoked in 39 of 41 forelimb motoneurons recorded after lesion of the corticospinal fibers in C5. After a corresponding lesion in C(2), disynaptic pyramidal EPSPs were observed in 2 of 25 motoneurons. In contrast to previous reports, we conclude that C(3)-C(4) PNs can mediate disynaptic pyramidal excitation in high frequency of occurrence to forelimb motoneurons in the C(6)-C(8) segments and that this transmission is under a stronger inhibitory control than in the cat. Thus, the hypothesis that the disynaptic excitatory cortico-motoneuronal pathway via the C(3)-C(4) PNs is weakened in parallel with the strengthened monosynaptic connection through phylogeny is not supported by the present findings.


Asunto(s)
Miembro Anterior/fisiología , Neuronas Motoras/fisiología , Propiocepción/fisiología , Tractos Piramidales/fisiología , Médula Espinal/fisiología , Anestesia , Animales , Estimulación Eléctrica , Miembro Anterior/inervación , Glicinérgicos/farmacología , Interneuronas/efectos de los fármacos , Interneuronas/fisiología , Macaca , Neuronas Motoras/efectos de los fármacos , Fibras Nerviosas/efectos de los fármacos , Fibras Nerviosas/fisiología , Propiocepción/efectos de los fármacos , Tractos Piramidales/efectos de los fármacos , Médula Espinal/citología , Médula Espinal/efectos de los fármacos , Estricnina/farmacología
17.
Pediatr Nephrol ; 13(9): 880-5, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10603141

RESUMEN

To determine the postnatal changes in mineralocorticoid action on the cortical distal nephron in preterm neonates, we evaluated the transtubular potassium gradient (TTKG) and its relationship to other renal and non-renal parameters in 16 preterm neonates during the first 5 weeks of life. Preterm neonates were divided into two groups according to their gestational age: the first group (group A, n=9) had a gestational age less than 30 weeks and the second group (group B, n=7) had a gestational age over 30 weeks. TTKG in both groups increased significantly with postnatal age, and TTKG in group A was significantly lower than that in group B (P=0.0003; two-way repeated analysis of variance). TTKG in group A was significantly lower during the 2 weeks of postnatal life than that in full-term neonates [TTKG during 1st week (mean+/-SD) 3.73+/-1.32, P<0.00001; during 2nd week 7.77+/-3.60, P=0.0096 versus full-term neonates (n=19); 11.56+/-3.23]. TTKG in group B was significantly lower only during the 1st week of life (6.55+/-2.71, P=0.0013) compared with full-term neonates. Plasma aldosterone concentration did not correlate with TTKG value. Stepwise regression analysis showed that postnatal age, cortical lumen sodium concentration (CLNa), and clinical condition requiring the use of mechanical ventilation were independent variables that correlated significantly with TTKG. We postulate that the low TTKG level in preterm neonates might reflect the prematurity of renal function (early postnatal age, CLNa) and the condition(s), relating to immaturity, such as the use of mechanical ventilation.


Asunto(s)
Recien Nacido Prematuro/metabolismo , Túbulos Renales/metabolismo , Potasio/metabolismo , Factores de Edad , Aldosterona/sangre , Aldosterona/orina , Análisis de Varianza , Creatinina/sangre , Creatinina/orina , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Potasio/sangre , Potasio/orina , Análisis de Regresión , Sodio/sangre , Sodio/orina
18.
J Asthma ; 36(6): 503-9, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10498045

RESUMEN

To evaluate bronchial hyperresponsiveness (BHR) in infants with asthma and the influence of aging on BHR during the infantile period, bronchial reactivity to inhaled methacholine (BRm) in infants was monitored using the transcutaneous oxygen pressure (tcPO2) method. One hundred thirty-seven infants with asthma (from 1 to 5 years, mean 3.4 years) and 97 age-matched children without chronic respiratory diseases (from 6 months to 5 years, mean 2.1 years) were enrolled in this study. Consecutive doses of methacholine were doubled until a 10% decrease in tcPO2 from the baseline was reached. The cumulative dose of methacholine at the inflection point of tcPO2 (Dmin-PO2) was considered to represent the reactivity of tcPO2 to inhaled methacholine. Dmin-PO2 values in the asthma groups were lower than those in the control groups in each year-group from 1 to 5. There was no statistical difference in Dmin-PO2 among the 1-4-year-old asthma groups, but Dmin-PO2 in the 5-year-old asthma group was significantly lower than Dmin-PO2 in the 1-4-year-old asthma groups. The same age-related change in Dmin-PO2 was also seen in the control groups. There was no difference in age-related Dmin-PO2 change between the female group and the male group. We concluded that BRm in asthmatic children increases during the infantile period, and that the age-related changes in BRm, observed in both asthmatic and control infants, may have an effect on the clinical symptoms of asthma during childhood.


Asunto(s)
Asma/diagnóstico , Hiperreactividad Bronquial/diagnóstico , Pruebas de Provocación Bronquial , Broncoconstrictores , Cloruro de Metacolina , Factores de Edad , Monitoreo de Gas Sanguíneo Transcutáneo , Preescolar , Femenino , Humanos , Lactante , Masculino , Valores de Referencia
19.
Exp Brain Res ; 127(1): 43-53, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10424413

RESUMEN

The tuning of fingertip forces to the physical properties of objects during manipulation may be controlled partly by digit-specific mechanisms using local afferent information and partly by controllers that support interdigital coordination and use sensory information from more than one digit. In the present study we addressed digital interactions when humans used the tips of two fingers to restrain a pair of horizontally oriented plates from moving when subjected to tangential force loads in the distal direction. Subjects used the right and left index fingers in a bimanual grasp, and the right index and middle fingers in an unimanual grasp. The plates were loaded at unpredictable times by identical force profiles consisting of a force increase of up to a 3-N force plateau. The plates were concurrently loaded in 85% of the trials and each plate was loaded separately in 7% of the trials. For each plate, we measured its movement and the normal and tangential forces applied by the finger to restrain it. When a finger was loaded, the subject automatically responded by a normal force increase to a level that remained fairly constant during the subsequent load plateau. The initial part of this finger grasp response was affected by simultaneous loading of its partner finger; the magnitude of the response was boosted with a bimanual grasp, whereas the onset latency tended to be shorter with a unimanual grasp. Responses also occurred at a non-loaded finger during both bimanual and unimanual grasps, but these responses were weaker than those evoked when the same finger was loaded. In the bimanual grasp, they were largely characterized by a brief force pulse whose onset was delayed by some 15 ms compared with the response onset of the loaded finger, i.e., there was no sustained response. In the unimanual grasp, the onset of the response coincided in time with that of the accompanying (loaded) finger, and the dynamic response was stronger and prolonged, with more than one force rate peak. There was also a significant static response present. We conclude that during unimanual as well as bimanual reactive restrain tasks there are interactions between digits engaged in terms of neural control that facilitate the response of a digit when an accompanying digit is simultaneously loaded. However, digit-specific afferent inputs are necessary for eliciting the full-size reactive grasp responses required to successfully restrain the manipulandum.


Asunto(s)
Dedos/fisiología , Fuerza de la Mano/fisiología , Adulto , Femenino , Dedos/inervación , Lateralidad Funcional/fisiología , Humanos , Masculino , Persona de Mediana Edad
20.
J Appl Physiol (1985) ; 86(5): 1505-12, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10233111

RESUMEN

To investigate the pathogenesis of ultrasonically nebulized distilled water-induced airway narrowing, we studied the role of airway epithelial cells during a distilled water-inhalation challenge in an animal model of airway inflammation. Guinea pigs were divided into four groups: 1) a sham/saline (S/S) group: sham ozone followed by saline inhalation; 2) a sham/water (S/W) group: sham ozone followed by water inhalation; 3) an ozone/saline (O/S) group: ozone followed by saline inhalation; and 4) an ozone/water (O/W) group: ozone followed by water inhalation. After exposure to either 3.0 parts/million ozone or air at the same flow rate for 2 h, guinea pigs were anesthetized and tracheostomized, and then lung resistance (RL) was measured. For morphometric assessment, tissues were fixed with formaldehyde, stained with hematoxylin and eosin, and cut into transverse sections. Airway dimensions were either measured directly or calculated from the internal perimeter, the external perimeter, and airway wall area. There were no statistical differences in the values of RL before distilled water inhalation between the sham groups and the ozone groups. RL increased significantly after 10 min of distilled water inhalation in both the S/W group and the O/W group. In the S/W group, epithelial cells were swollen, and intercellular spaces were wider, resulting in significant increase in epithelial wall thickness, but there was no significant infiltration by inflammatory cells. In the O/S group, the epithelium showed infiltration by inflammatory cells without change in cell volume. In the O/W group, the epithelium showed both infiltration and a greater increase in epithelial wall thickness compared with the S/W group. These results suggest that airway epithelial cell swelling, induced by inhaled distilled water, increases with RL in guinea pigs and that this reaction may be accelerated by airway inflammation.


Asunto(s)
Células Epiteliales/ultraestructura , Agua/farmacología , Administración por Inhalación , Resistencia de las Vías Respiratorias/efectos de los fármacos , Resistencia de las Vías Respiratorias/fisiología , Algoritmos , Animales , Bronquios/efectos de los fármacos , Bronquios/patología , Hiperreactividad Bronquial/inducido químicamente , Hiperreactividad Bronquial/patología , Tamaño de la Célula/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Cobayas , Masculino , Nebulizadores y Vaporizadores , Oxidantes Fotoquímicos/toxicidad , Ozono/toxicidad , Ultrasonido , Agua/administración & dosificación
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