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1.
Phys Rev Lett ; 124(22): 222504, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32567915

RESUMEN

We report the measurement of reaction cross sections (σ_{R}^{ex}) of ^{27,29}F with a carbon target at RIKEN. The unexpectedly large σ_{R}^{ex} and derived matter radius identify ^{29}F as the heaviest two-neutron Borromean halo to date. The halo is attributed to neutrons occupying the 2p_{3/2} orbital, thereby vanishing the shell closure associated with the neutron number N=20. The results are explained by state-of-the-art shell model calculations. Coupled-cluster computations based on effective field theories of the strong nuclear force describe the matter radius of ^{27}F but are challenged for ^{29}F.

2.
Phys Rev Lett ; 121(26): 262501, 2018 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-30636164

RESUMEN

An enhanced low-energy electric dipole (E1) strength is identified for the weakly bound excited states of the neutron-rich isotope ^{27}Ne. The Doppler-shift lifetime measurements employing a combination of the γ-ray tracking array GRETINA, the plunger device, and the S800 spectrograph determine the lower limit of 0.030 e^{2} fm^{2} or 0.052 W.u. for the 1/2^{+}→3/2^{-} E1 transition in ^{27}Ne, representing one of the strongest E1 strengths observed among the bound discrete states in this mass region. This value is at least 30 times larger than that measured for the 3/2^{-} decay to the 3/2_{gs}^{+} ground state. A comparison of the present results to large-scale shell-model calculations points to an important role of core excitations and deformation in the observed E1 enhancement, suggesting a novel example of the electric dipole modes manifested in weakly bound deformed systems.

3.
Spinal Cord ; 53(11): 786-90, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25962372

RESUMEN

STUDY DESIGN: This is a cross-sectional study. OBJECTIVES: The objective of this study was to ascertain the essential items mediating adequate dietary intake based on the Japanese Food Guide in common among the transtheoretical model (TTM), self-efficacy (SE) and outcome expectancy (OE). SETTING: Members of the organization Spinal Injuries Japan. METHODS: We posted a questionnaire survey to 2731 community-dwelling Japanese adults with spinal cord injury (SCI), and responses from 841 individuals were analyzed. Food intake was assessed as the frequency scores of 10 food items eaten in a daily diet in Japan. The correlations between the frequency scores of food intake and TTM, SE and OE were determined by binominal logistic regression analysis. RESULTS: The frequency scores of food intake were significantly associated with 'To eat vegetable dishes (dishes made mainly from vegetables or potatoes) not less than twice a day', 'To eat green/yellow vegetables not less than twice a day', 'To eat dairy products not less than once a day' and 'To eat fruits not less than once a day' in TTM. 'To eat vegetable dishes (dishes made mainly from vegetables or potatoes) not less than twice a day', 'To eat dairy products not less than once a day' and 'To eat fruits not less than once a day' were significantly associated with the frequency scores of food intake in SE. In OE, no differences were shown. CONCLUSION: This study finds that vegetable dishes, dairy products and fruits are the key items mediating adequate dietary intake. Dietary guidelines promoting the intake of these dishes for SCI individuals are needed.


Asunto(s)
Dieta/estadística & datos numéricos , Ingestión de Alimentos , Conducta Alimentaria , Alimentos , Traumatismos de la Médula Espinal/psicología , Adulto , Factores de Edad , Anciano , Estudios Transversales , Productos Lácteos , Encuestas sobre Dietas , Conducta Alimentaria/psicología , Femenino , Frutas , Humanos , Japón , Masculino , Persona de Mediana Edad , Modelos Teóricos , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/epidemiología , Encuestas y Cuestionarios , Verduras , Adulto Joven
4.
Spinal Cord ; 52(11): 836-41, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25266697

RESUMEN

STUDY DESIGN: Cross-sectional study. OBJECTIVES: There are ethnic differences in the distribution of abdominal obesity associated with metabolic disorders. In Japan, the appropriate reference values for abdominal obesity have not been established in individuals with spinal cord injury (SCI), although there are a number of studies in Western countries. This study evaluates the associations between visceral fat area (VFA), waist circumference (WC) and body mass index (BMI), to examine cutoffs and estimate the error for WC and BMI equivalent to 100 cm(2) VFA in Japanese men with SCI. SETTING: National Rehabilitation Center for Persons with Disabilities, Japan. METHODS: Seventy-four men (aged 45.6 (s.d. 14.3) years) participated in the study. VFA was quantified using computed tomography at the level of the umbilicus, and associations were determined using nonlinear regression analysis. The error of the estimates from the regression equation was assessed using a Bland-Altman plot. RESULTS: The mean VFA was 101.2 (s.d. 53.0) cm(2) and 32 subjects had a VFA ⩾100 cm(2). The cutoffs for a VFA of 100 cm(2) were WC, 81.3 cm and BMI, 22.5 kg m(-2). The relationship between the estimated and actual values showed that the error increased as VFA increased, which resulted in a negative proportional bias. CONCLUSION: The suggested cutoff for Japanese men with SCI is a VFA of 100 cm(2), which is lower than that in the healthy able-bodied population for both WC and BMI. Further investigation is needed to determine the reference value for estimating SCI-specific VF accumulation.


Asunto(s)
Índice de Masa Corporal , Grasa Intraabdominal/patología , Obesidad/patología , Circunferencia de la Cintura , Adulto , Factores de Edad , Anciano , Estudios Transversales , Ejercicio Físico , Humanos , Grasa Intraabdominal/diagnóstico por imagen , Japón , Masculino , Persona de Mediana Edad , Radiografía , Valores de Referencia , Estudios Retrospectivos , Sensibilidad y Especificidad , Estadísticas no Paramétricas , Tomógrafos Computarizados por Rayos X , Adulto Joven
5.
Int J Sports Med ; 35(10): 828-34, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24577863

RESUMEN

The purpose of this study was to investigate growth changes in human plantar flexor muscle and tendons. In addition, we ascertained whether growth changes in muscle and tendon were more closely related to skeletal age than chronological age. 22 elementary school children (ESC), 19 junior high school students (JHS), and 23 young adults (ADT) men participated in this study. Maximal strain and hysteresis of tendon structures and cross-sectional area of Achilles tendon were measured using ultrasonography. In addition, skeletal age was assessed using Tanner-Whitehouse III method. Maximal strain of ESC was significantly greater than that of other groups, while no significant difference was observed between JHS and ADT. There was no difference in hysteresis among 3 groups. Relative cross-sectional area (to body mass(2/3)) of ADT was significantly smaller than that of other groups. For ESC and JHS, measured variables of muscle and tendon were significantly correlated to both chronological and skeletal ages. These results suggested that immature musculoskeletal system was protected by more extensible and larger tendon structures in ESC and only by larger tendon structures in JHS, respectively. Furthermore, there were no differences in correlation coefficient values between measured variables of muscle and tendon and chronological or skeletal ages.


Asunto(s)
Tendón Calcáneo/crecimiento & desarrollo , Pie/crecimiento & desarrollo , Músculo Esquelético/crecimiento & desarrollo , Tendón Calcáneo/diagnóstico por imagen , Adolescente , Adulto , Determinación de la Edad por el Esqueleto , Niño , Estudios Transversales , Pie/diagnóstico por imagen , Humanos , Masculino , Fuerza Muscular/fisiología , Músculo Esquelético/diagnóstico por imagen , Ultrasonografía , Adulto Joven
6.
Int J Sports Med ; 34(1): 56-61, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22903318

RESUMEN

This study aimed to examine and compare the trunk muscularity of track and field throwers and non-athletes, and its predictive value to the physical performance of the athletes. Using a magnetic resonance imaging method, the skeletal muscle volume (SMV) of the trunk (SMV(trunk)) was determined in 19 strength trained athletes and 18 non-athletes. Also, the SMV of upper, middle and lower regions of the trunk was calculated in every 33% of the trunk length. For the athletes, the maximum weight (1RM) of squat, high clean, and deadlift, and shot forward throwing score were measured. The SMV(trunk) in the athletes was 10% greater than that of non-athletes, with a larger difference in the upper region of the trunk. Step-wise multiple regression analysis indicated that the SMV of the lower region was a significant contributor for predicting the 1RM values of the 3 tasks, as well as the shot forward throwing score. The current results indicate that, while the muscularity of the trunk in track and field throwers is characterized by predominant development in the upper region, the muscularity in the lower region is a determinant factor for the 1RM values of the squat, high clean, and deadlift and shot forward throwing score.


Asunto(s)
Rendimiento Atlético/fisiología , Composición Corporal/fisiología , Músculo Esquelético/fisiología , Atletismo/fisiología , Adolescente , Adulto , Atletas , Humanos , Imagen por Resonancia Magnética , Masculino , Valor Predictivo de las Pruebas , Análisis de Regresión , Entrenamiento de Fuerza , Adulto Joven
7.
Horm Metab Res ; 43(13): 950-5, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22113420

RESUMEN

Trigonella foenum-graecum L. (fenugreek) has been described earlier and its use in ancient medicinal practice is well known. The hypoglycemic effects of fenugreek have been studied in many animal models and diabetic patients. The purpose of this study was to examine the preventive efficiency of dietary fenugreek on diet-induced metabolic diseases in rats. The diets used in this study were a standard diet, a high-fat high-sucrose (HFS) diet, and a HFS diet containing 0.5 g/kg b. w./day fenugreek based on the modified version of the AIN-93G purified diet, for 12 weeks, respectively. The rats fed the HFS diet containing fenugreek showed significantly lower fasting insulin levels and HOMA-IR than the rats fed the HFS diet. Therefore, fenugreek improved insulin sensitivity in rats. The triglyceride and total cholesterol levels in the plasma were significantly lower in the fenugreek-administered group. Moreover, distinct reductions of triglyceride, total cholesterol, free fatty acid, and phospholipid levels in the liver were found in the rats fed the HFS diet containing fenugreek. These results suggest that fenugreek enhanced insulin sensitivity at least partly by improving lipid metabolism disorders in the plasma and the liver in the rats induced by the HFS diet.


Asunto(s)
Carbohidratos de la Dieta/efectos adversos , Grasas de la Dieta/efectos adversos , Enfermedades Metabólicas/tratamiento farmacológico , Enfermedades Metabólicas/etiología , Extractos Vegetales/uso terapéutico , Trigonella/química , Animales , Colesterol/metabolismo , Dieta Alta en Grasa/efectos adversos , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Humanos , Resistencia a la Insulina , Hígado/metabolismo , Masculino , Enfermedades Metabólicas/metabolismo , Ratas , Ratas Sprague-Dawley , Triglicéridos/metabolismo
8.
J Stomatol Oral Maxillofac Surg ; 122(3): 267-272, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32622002

RESUMEN

Cryosurgery is a recognized method for the treatment of mucoceles in the oral cavity. In this study, cryosurgery was used for mucoceles at the lip or buccal mucosa, and the effect and the indication were evaluated clinically. The subjects were patients with a clinical diagnosis of mucocele on the lip or buccal mucosa and who chose cryosurgery after procedures for both surgical excision and cryosurgery for the lesion were explained. Cryosurgery was performed with a freezing device using liquid nitrogen without local anesthesia. Twenty-four patients chose cryosurgery, including seven preschool children. There were no serious adverse events during and after cryosurgery. Healing progress after cryosurgery was not affected by patient age, lesion size, or how long the patients had the lesion. Two cases later underwent surgical excision because cryosurgery was not successful. Twenty-three patients chose surgical excision, one case had a recurrence. The number of younger patients who chose cryosurgery was significantly higher than that who chose surgical excision. This study suggests that cryosurgery is effective for mucoceles of the lip or buccal mucosa and is a simple and safe treatment method, especially for preschool children.


Asunto(s)
Criocirugía , Enfermedades de la Boca , Mucocele , Preescolar , Criocirugía/efectos adversos , Humanos , Enfermedades de la Boca/cirugía , Mucocele/diagnóstico , Mucocele/cirugía , Recurrencia Local de Neoplasia
9.
Adv Exp Med Biol ; 662: 347-52, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20204814

RESUMEN

Heavy resistance exercise may be associated with a small risk of cerebral aneurysm rupture, subarachnoid hemorrhage, and symptoms of dizziness or outright weight-lifters' blackout, which may be induced by a rapid change in the cerebral blood flow. We hypothesized that these changes during heavy exercise could be associated with the mode of ventilation. The purpose of the present study was to elucidate the effect of the mode of ventilation on cerebral blood flow response during heavy upper body exercise. Subjects performed 15-s static exercises at 80% maximum voluntary contraction (MVC) under different modes of ventilation. In this study, we observed that heavy exercise with breath holding induced marked and rapid changes in the cerebral blood flow velocity in the middle cerebral artery during and after exercise as compared with that with continued normal ventilation. We also observed that hyperventilation before exercise could largely contribute to a lower cerebral blood flow velocity during exercise and which even extended to the recovery phase. Our data suggested that even during heavy upper body exercise, the mode of ventilation is very important for maintaining cerebral circulation.


Asunto(s)
Circulación Cerebrovascular/fisiología , Prueba de Esfuerzo , Arteria Cerebral Media/fisiología , Ventilación Pulmonar/fisiología , Velocidad del Flujo Sanguíneo/fisiología , Humanos , Masculino , Adulto Joven
10.
Chest ; 94(2): 438-40, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3396429

RESUMEN

We treated a patient with Sjögren's syndrome associated with multiple bullae and pulmonary nodular amyloidosis, both of which were identified by open lung biopsy. The mechanism of bullae formation appeared to be narrowing of the airway, as a result of extensive inflammatory cell infiltration to the bronchiolar wall, which acted as the check valve mechanism. We believe this to be the first reported case of Sjögren's syndrome accompanied by these two pulmonary manifestations.


Asunto(s)
Amiloidosis/patología , Enfermedades Pulmonares/patología , Pulmón/patología , Síndrome de Sjögren/complicaciones , Amiloidosis/complicaciones , Femenino , Humanos , Enfermedades Pulmonares/complicaciones , Persona de Mediana Edad
11.
Chest ; 98(1): 243-5, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2361399

RESUMEN

A middle-aged woman developed fulminant respiratory failure during recovery from Stevens-Johnson syndrome. Mechanical ventilation was difficult because of unusually high airway pressures, and she died one month later. Autopsy revealed not only the usual features of bronchiolitis obliterans, but also obstruction of cartilaginous bronchi. The histopathologic features suggested a relationship between bronchial obstruction and Stevens-Johnson syndrome.


Asunto(s)
Bronquiolitis Obliterante/etiología , Síndrome de Stevens-Johnson/complicaciones , Adulto , Bronquios/patología , Bronquiolitis Obliterante/patología , Epitelio/patología , Femenino , Humanos
12.
Metabolism ; 45(12): 1539-46, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8969289

RESUMEN

Mice fed a high-fat diet develop hyperglycemia and obesity. Using non-insulin-dependent diabetes mellitus (NIDDM) model mice, we investigated the effects of seven different dietary oils on glucose metabolism: palm oil, which contains mainly 45% palmitic acid (16:0) and 40% oleic acid (18:1); lard oil, 24% palmitic and 44% oleic acid; rapeseed oil, 59% oleic and 20% linoleic acid (18:2); soybean oil, 24% oleic and 54% linoleic acid; safflower oil, 76% linoleic acid; perilla oil, 58% alpha-linolenic acid; and tuna fish oil, 7% eicosapentaenoic acid and 23% docosahexaenoic acid. C57BL/6J mice received each as a high-fat diet (60% of total calories) for 19 weeks (n = 6 to 11 per group). After 19 weeks of feeding, body weight induced by the diets was in the following order: soybean > palm > or = lard > or = rapeseed > or = safflower > or = perilla > fish oil. Glucose levels 30 minutes after a glucose load were highest for safflower oil (approximately 21.5 mmol/L), modest for rapeseed oil, soybean oil, and lard (approximately 17.6 mmol/L), mild for perilla, fish, and palm oil (approximately 13.8 mmol/L), and minimal for high-carbohydrate meals (approximately 10.4 mmol/L). Only palm oil-fed mice showed fasting hyperinsulinemia (P < .001). By stepwise multiple regression analysis, body weight (or white adipose tissue [WAT] weight) and intake of linoleic acid (or n-3/n-6 ratio) were chosen as independent variables to affect glucose tolerance. By univariate analysis, the linoleic acid intake had a positive correlation with blood glucose level (r = .83, P = .02) but not with obesity (r = .46, P = .30). These data indicate that (1) fasting blood insulin levels vary among fat subtypes, and a higher fasting blood insulin level in palm oil-fed mice may explain their better glycemic control irrespective of their marked obesity; (2) a favorable glucose response induced by fish oil feeding may be mediated by a decrease of body weight; and (3) obesity and a higher intake of linoleic acid are independent risk factors for dysregulation of glucose tolerance.


Asunto(s)
Grasas Insaturadas en la Dieta/administración & dosificación , Hiperglucemia/etiología , Obesidad/etiología , Animales , Diabetes Mellitus Tipo 2/fisiopatología , Modelos Animales de Enfermedad , Femenino , Prueba de Tolerancia a la Glucosa , Ratones , Ratones Endogámicos C57BL
13.
Metabolism ; 47(6): 724-30, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9627373

RESUMEN

A high-monounsaturated fat diet has been proposed as a palatable alternative to a high-carbohydrate diet in diabetic patients, but it is unknown whether a higher intake of monounsaturated fat induces obesity and diabetes, as usually observed with other types of fat. To answer this question, C57BL/6J mice were divided into three groups: the first group was given a high-carbohydrate diet, and the other two groups were given a high-monounsaturated fat diet (60% of total energy) as olive oil or synthetic triolein for 4 months. It has been previously reported that the C57BL/6J mouse has a genetic predisposition for intraabdominal obesity and non-insulin-dependent diabetes mellitus (NIDDM) by high-polyunsaturated fat (n-6) feeding. Although there were no significant differences in energy intake and fat absorption among these three groups, compared with the high-carbohydrate diet, both high-monounsaturated fat diets produced hyperglycemia, obesity, and triglyceride accumulation in the liver and skeletal muscle. These data indicate that the recently recommended high-monounsaturated fat diet might induce obesity and diabetes.


Asunto(s)
Diabetes Mellitus/etiología , Grasas Insaturadas en la Dieta/administración & dosificación , Obesidad/etiología , Animales , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/farmacología , Grasas Insaturadas en la Dieta/farmacología , Femenino , Hiperglucemia/etiología , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , Triglicéridos/metabolismo
14.
J Chromatogr A ; 824(2): 211-21, 1998 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-9818434

RESUMEN

The efficiency of pretreatment of aqueous soil extracts using a cation-exchange resin has been investigated by gas chromatographic-mass spectrometric (GC-MS) determination of nerve agent hydrolysis products after tert.-butyldimethylsilyl (TBDMS) derivatization. An aqueous solution containing methylphosphonic acid (MPA) and its monoalkyl esters, ethyl methylphosphonic acid, isopropyl methylphosphonic acid and pinacolyl methylphosphonic acid, was dried, and these phosphonic acids were derivatized with N-methyl-N-(tert.-butyldimethylsilyl)trifluoro-acetamide and analyzed by GC-MS. The yields of TBDMS derivatives were significantly decreased by the addition of calcium and magnesium ions to an aqueous solution (approximately 0.5 mM) before derivatization. The extent of lowered yields was related to the hydrophilicity of phosphonic acids. MPA and its monoalkyl esters were spiked into soil samples (sand, alluvial soil and volcanic ash soil), extracted with distilled water, dried, silylated and applied to GC-MS. The yields of TBDMS derivatives of monoalkyl esters from soil samples were low (3-42%) and MPA derivative was scarcely detected (yield: < 0.7%). By desalting the aqueous soil extract by passage through a strong cation-exchange resin, the yields of TBDMS derivatives of monoalkyl esters were significantly improved (12-69%) and MPA derivative was detected (yield: 2-36%). The extent of improved yields was related to the concentrations of divalent metal cations in aqueous soil extracts. In combination with desalting by the cation-exchange resin, GC-MS after TBDMS derivatization enables detection of nerve agent hydrolysis products in soils at sub-ppm (0.2 microgram/g) concentrations.


Asunto(s)
Resinas de Intercambio de Catión , Sustancias para la Guerra Química , Sustancias para la Guerra Química/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Compuestos Organofosforados/análisis , Suelo/análisis , Acetamidas , Cationes , Sustancias para la Guerra Química/química , Fluoroacetatos , Hidrólisis , Metales/farmacología , Sistema Nervioso/efectos de los fármacos , Compuestos Organofosforados/química , Compuestos de Organosilicio/química , Ácido Trifluoroacético/química , Agua
15.
Steroids ; 39(6): 657-66, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6760470

RESUMEN

An enzyme immunoassay for estrone in swine serum was established. For this, beta-galactosidase from E. coli was conjugated through estrone-17 (O-carboxymethyl)oxime using a mixed anhydride reaction. The percentage of immunoreactive estrone-17 (O-carboxymethyl)oxime-beta-galactosidase conjugate was estimated to be about 70%. The recovery rate of estrone (25-500 pg) added to 0.05 ml of swine serum averaged 91.4%. The sensitivity of the present enzyme immunoassay was 5 pg/tube. The coefficients of variation (CV) were 5.9-8.2% (within assays) and 4.1-5.9% (between assays), respectively. Estrone values determined by the present enzyme immunoassay were highly correlated with those determined by radioimmunoassay (r = 0.99, P less than 0.005). This method of enzyme immunoassay was determined to be suitable for the routine assay of serum estrone.


Asunto(s)
Estrona/sangre , Animales , Estradiol/sangre , Femenino , Técnicas para Inmunoenzimas , Métodos , Embarazo , Porcinos
16.
Steroids ; 38(1): 111-20, 1981 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6270851

RESUMEN

A double antibody enzyme immunoassay of plasma cortisol was established using beta-galactosidase from E. coli as the tracer. Cortisol-21-hemisuccinate was conjugated with beta-galactosidase using a water-soluble carbodiimide. An antibody raised in the rabbit against cortisol-21-hemisuccinate-bovine serum albumin was used as the first antibody and anti-rabbit gamma-globulin goat serum was used as the second. The sensitivity of the present enzyme immunoassay was 25 pg/tube. The method satisfied general reliability criteria regarding specificity, accuracy and precision. Plasma cortisol levels estimated by the enzyme immunoassay was highly correlated (r = 0.99, P less than 0.005) with the levels measured by radioimmunoassay. This method of enzyme immunoassay was found to be of practical application to the routine assay of plasma cortisol.


Asunto(s)
Hidrocortisona/sangre , Hormona Adrenocorticotrópica/farmacología , Animales , Bovinos , Reacciones Cruzadas , Técnicas para Inmunoenzimas , beta-Galactosidasa
17.
Reprod Fertil Dev ; 8(8): 1137-45, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8981637

RESUMEN

Plasma concentrations of immunoreactive (ir)-inhibin were measured in seven pregnant mares from around Day 140 of gestation to Day 2 after parturition using a heterologous bovine-based radioimmunoassay (RIA). Concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), oestradiol-17 beta, progesterone and relaxin were also measured in the same samples. A marked increase in plasma concentrations of ir-inhibin, FSH and LH occurred between Day 220 and Day 300 of gestation but the concentrations of all three hormones returned to baseline by about Day 320 (three weeks before parturition). In contrast, circulating concentrations of the three placental hormones, oestradiol-17 beta, progesterone and relaxin, increased during the final weeks of pregnancy and then decreased markedly to basal values within two days of parturition. There was a positive correlation between circulating concentrations of ir-inhibin and FSH (r = 0.75, P < 0.01) rather than the expected negative correlation. ir-inhibin was not detected in homogenates obtained at Day 190 of pregnancy and form term placenta, but high concentrations of ir-inhibin were present in homogenates of fetal and newborn gonads. Despite the high concentrations of ir-inhibin in these homogenates, they failed to exert any suppressive bioactivity on FSH secretion by rat pituitary cells cultured in vitro. Furthermore, immunohistochemical staining revealed the presence of inhibin in the interstitial cells of equine fetal gonads at Day 190 of gestation. These findings demonstrate for the first time that high concentrations of ir-inhibin, LH and FSH are secreted into the peripheral circulation of the mare during the second half of pregnancy. However, ir-inhibin present in the plasma of pregnant mares appears to be biologically inactive. This hormone is not presumed to be of placental origin but it is proposed that either the enlarged fetal gonads or the maternal ovaries, or both of these organs, may be a source of inhibin in response to the coincident increase in circulating concentrations of LH and FSH.


Asunto(s)
Caballos/sangre , Inhibinas/sangre , Ovario/química , Preñez/sangre , Testículo/química , Animales , Animales Recién Nacidos/sangre , Animales Recién Nacidos/metabolismo , Bioensayo/veterinaria , Bovinos , Estradiol/sangre , Estradiol/metabolismo , Femenino , Hormona Folículo Estimulante/sangre , Hormona Folículo Estimulante/metabolismo , Caballos/embriología , Caballos/metabolismo , Inmunohistoquímica , Inhibinas/inmunología , Inhibinas/metabolismo , Hormona Luteinizante/sangre , Hormona Luteinizante/metabolismo , Masculino , Ovario/embriología , Ovario/metabolismo , Adenohipófisis/citología , Adenohipófisis/metabolismo , Placenta/química , Embarazo , Preñez/metabolismo , Progesterona/sangre , Progesterona/metabolismo , Radioinmunoensayo/veterinaria , Ratas , Análisis de Regresión , Relaxina/sangre , Relaxina/metabolismo , Testículo/embriología , Testículo/metabolismo
18.
J Anal Toxicol ; 17(7): 415-20, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8309215

RESUMEN

Headspace (HS) capillary gas chromatography with flame-ionization detection was developed for the determination of chloroform levels in blood. Separation of chloroform was improved significantly using a DB-WAX capillary column, without interference by other volatile substances. Sensitivity was increased by adjusting the splitter ratio to 20, without any decline in peak resolution. The HS conditions, a 50 degrees C incubation for 30 min, gave reproducible and sensitive determinations. The distribution coefficient (k) was calculated to be 8.24. The CV was 1.8% for 27.7 micrograms/mL chloroform, and the detection limit was 0.02 microgram/mL (S/N = 4) when the splitter ratio was 10. Raising HS temperature resulted in a significant decrease in k for chloroform in the absence of blood, in contrast to the relatively small effect seen in the presence of blood. Although inorganic salts showed a salting-out effect, erythrocytes and hydrophobic compounds, such as detergent and lipid, significantly suppressed the vaporization of chloroform. Chloroform was found to be distributed mainly in erythrocytes when incubated with blood overnight at 2 degrees C.


Asunto(s)
Cloroformo/sangre , Cromatografía de Gases/métodos , Cromatografía de Gases/instrumentación , Humanos , Metanol/sangre
19.
ASAIO J ; 45(5): 418-23, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10503618

RESUMEN

A great deal of research has been conducted focusing on membrane materials with reference to their blood compatibility, but blood compatibility is influenced both by the material used in membranes and their structure, and by the flow conditions at the membrane surface. Accordingly, the relationship between membrane surface roughness and hemocompatibility has been evaluated using five types of membranes of differing surface roughness by evaluating the inner surfaces of the hollow fibers by atomic force microscopy (AFM) and by measuring platelet adhesion ratios using bovine blood. The yield stress, which equates to flow characteristics, was also evaluated using a glycerol suspension of polymethylmethacrylate (PMMA), a Bingham fluid. It was found that membranes having rough surfaces had high platelet adhesion ratios and poor hemocompatibility, whereas those with smoother surfaces had lower platelet adhesion ratios and better hemocompatibility. Measurement of the yield stresses for these membranes revealed higher values for those with rough surfaces, and lower values for those with smoother polyethylene glycol (PEG) grafted surfaces. This suggests that flow conditions at the membrane surface differ according to its surface roughness, and that this difference in flow conditions also influences hemocompatibility.


Asunto(s)
Membranas Artificiales , Adhesividad Plaquetaria , Diálisis Renal , Celulosa , Humanos
20.
J Comp Pathol ; 124(2-3): 122-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11222008

RESUMEN

Histopathological and immunohistochemical examinations were made on four female horses aged 9-12 years with pulmonary granular cell tumours (GCTs). The tumours, which were multiple, of varying size, firm and off-white in colour, surrounded the bronchi and bronchioles. Metastatic lesions were not detected. The tumour cells had abundant eosinophilic cytoplasm filled with prominent coarse eosinophilic granules. Immunohistochemically, these tumour cells reacted uniformly with vimentin and S100 antibodies. Most were immunolabelled by antibodies against glial fibrillary acidic protein (GFAP), myelin basic protein (MBP) and protein gene product 9.5 (PGP9.5), and a few cells were positive with Leu7 antibody. However, the tumour cells did not react with antibodies against neurofilament protein (NF), cytokeratin (CK), chromogranin, alpha1 antichymotrypsin (AACT), myoglobin, desmin, alpha-actin or alpha-smooth muscle actin (alpha-SMA). These immunohistochemical properties of tumour cells support the hypothesis that equine pulmonary GCTs are derived from Schwann cells of the peripheral nervous system in peribronchial and peribronchiolar tissues. GFAP, MBP, Leu7 and PGP9.5 antibodies should help to distinguish equine granular cell tumours from other tumours.


Asunto(s)
Tumor de Células Granulares/veterinaria , Enfermedades de los Caballos/patología , Neoplasias Pulmonares/veterinaria , Animales , Biomarcadores de Tumor/metabolismo , Femenino , Tumor de Células Granulares/química , Tumor de Células Granulares/patología , Enfermedades de los Caballos/metabolismo , Caballos , Humanos , Técnicas para Inmunoenzimas/veterinaria , Neoplasias Pulmonares/química , Neoplasias Pulmonares/patología , Proteínas de Neoplasias/metabolismo , Especificidad de la Especie
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