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1.
J Biol Regul Homeost Agents ; 32(4): 781-790, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30043560

RESUMEN

The purpose of this study was to concomitantly determine oxidative DNAdamage and bone resorption following a rapid body mass reduction in association with energy restriction and exercise training, considering 17ß-estradiol level, in female collegiate judokas. Eighteen nationally ranked university female judokas were enrolled as participants in this study. All participants continuously managed to reduce their body mass 8 days just before a competition. To detect cumulative effects of oxidative DNA damage and bone resorption, urinary samples were collected in the morning on three different days (Day 1= the beginning of body mass reduction; Day 4=mid-term of body mass reduction; Day 7=the day before the competition) for the later analysis of 8-hydroxy-2’- deoxyguanosine (8-OHdG) as well as cross-linked N-terminal telopeptides of Type I collagen (NTx). Urinary 8-OHdG and NTx levels were determined with high performance liquid chromatography and enzyme-linked immunosorbent assay, respectively. No significant alterations were observed in urinary 8-OHdG or NTx levels over a rapid body mass reduction period. The findings of the present study indicate that female judokas appear to have relatively less oxidative DNA damage determined by quantification of 8-OHdG and bone resorption over a rapid body mass reduction period, potentially due to the enhanced endogenous defense responses (training adaptation). These data can provide athletes and coaches with valuable information in considering an optimal body mass management program to avoid detrimental physiological and biological conditions.


Asunto(s)
Atletas , Peso Corporal/fisiología , Resorción Ósea , Daño del ADN/fisiología , Ejercicio Físico/fisiología , 8-Hidroxi-2'-Desoxicoguanosina , Composición Corporal/fisiología , Restricción Calórica , Colágeno Tipo I/orina , Desoxiguanosina/análogos & derivados , Desoxiguanosina/orina , Femenino , Humanos , Artes Marciales , Estrés Oxidativo/fisiología , Adulto Joven
2.
Clin Exp Allergy ; 34(9): 1467-73, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15347382

RESUMEN

BACKGROUND: Since dogs frequently develop allergic diseases, similar to those in humans, dogs represent a possible animal model for allergy in humans. In human atopic dermatitis (AD), CC chemokine receptor 4 (CCR4) has been shown to play an important role in the development of allergic inflammation of AD; however, the association between allergic reaction and CCR4 is not well understood in dogs. OBJECTIVE: To examine CCR4 expression in peripheral blood CD4+ cells in dogs that had AD and were experimentally sensitized with Japanese cedar pollen. MATERIALS AND METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from 17 dogs with AD. The proportion of CCR4+ cells in peripheral blood CD4+ cells (CCR4/CD4) was evaluated by flow cytometry and compared with that in 10 healthy dogs. Similarly, in dogs that were experimentally sensitized to Japanese cedar pollen antigen, the proportion of CCR4/CD4 was examined pre- and post-sensitization. RESULTS: The proportion of CCR4/CD4 in dogs with AD was 40.3+/-3.3%, which was significantly higher than that in normal dogs (23.6+/-4.3%) (P<0.01). In the experimentally sensitized dogs, the proportion of CCR4/CD4 was 25.4+/-2.6% at pre-sensitization and it was significantly increased (29.8+/-2.9%) at post-sensitization (P<0.01). CONCLUSION: The proportion of CCR4+ cells in peripheral blood CD4+ cells was measured in dogs with allergic conditions. The present findings indicate that CCR4+ cells may be involved in the pathogenesis of allergy in dogs as in humans.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Cryptomeria/inmunología , Dermatitis Atópica/inmunología , Enfermedades de los Perros/inmunología , Polen/inmunología , Receptores de Quimiocina/análisis , Alérgenos/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Quimiocinas CC/inmunología , Reacciones Cruzadas/inmunología , Modelos Animales de Enfermedad , Perros , Femenino , Humanos , Leucocitos Mononucleares/inmunología , Masculino , Proteínas de Plantas/inmunología , ARN Mensajero/análisis , Receptores CCR4 , Receptores de Quimiocina/inmunología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos
3.
Jpn J Physiol ; 47(2): 147-59, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9201544

RESUMEN

Although CRH is the major contributor to the physiological regulation of ACTH secretion, it must be recognized that a considerable degree of heterogeneity exists regarding the chemistry and biological activity of various CRF-active substances, some of which still remain to be fully clarified. The widespread extrahypothalamic sources and diverse extrapituitary actions of CRFs suggest that multiple CRF components must act in concert for the organism to cope with the environmental changes and stresses.


Asunto(s)
Hormona Liberadora de Corticotropina/fisiología , Hipotálamo/metabolismo , Placenta/metabolismo , Hormona Adrenocorticotrópica/metabolismo , Secuencia de Aminoácidos , Animales , Proteínas Portadoras/metabolismo , Cromatografía en Gel , Hormona Liberadora de Corticotropina/sangre , Hormona Liberadora de Corticotropina/química , Hormona Liberadora de Corticotropina/aislamiento & purificación , Femenino , Humanos , Datos de Secuencia Molecular , Embarazo , Homología de Secuencia de Aminoácido , Estrés Fisiológico/metabolismo
4.
NMR Biomed ; 10(6): 257-62, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9449128

RESUMEN

Biochemical changes that occur within hepatic tissue of the rat during ischemia and subsequent reperfusion were investigated using magnetic resonance spectroscopy of liver extracts. Hepatic ischemia was produced in the rat by a continuous clamping of the left branches of the hepatic artery and portal vein. In the reperfusion experiments, the vascular clamps were released after 30 or 120 min of ischemic periods. At the end of the periods of ischemia and/or reperfusion, the left and middle hepatic lobes were dissected and processed for subsequent 1H-MRS and 31P-MRS analyses. Phosphatidylcholine, sphingomyelin, phosphatidic acid and phosphatidylethanolamine contents all showed reduction of about 30% after 120 min of ischemia. In contrast, the content of lysophosphatidylcholine showed relatively small changes following ischemia. Ten minutes after initiation of reperfusion, further decline of the total phospholipid content resulting in as much 42% reduction was observed. Then it recovered to nearly the control level when ischemia was for 30 min, but to only 65% of the control level when ischemia was for 120 min. The cholesterol/-N-(CH3)3 ratio, generally regarded as a parameter for membrane fluidity, showed about a 40% increase when ischemia was for 120 min, a change toward decreased membrane fluidity. These results appear to reflect ischemia/reperfusion-induced changes of membrane phospholipid metabolism.


Asunto(s)
Isquemia/metabolismo , Hígado/irrigación sanguínea , Hígado/ultraestructura , Resonancia Magnética Nuclear Biomolecular/métodos , Animales , Membrana Celular/metabolismo , Ligadura , Fósforo , Protones , Ratas , Ratas Wistar , Reperfusión
5.
Metabolism ; 45(11): 1330-4, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8931635

RESUMEN

Hypersecretion of prolactin (PRL) has been implicated as one of the factors that mediate ethanol-induced hypogonadism, but the site(s) in the central nervous system where ethanol acts to lead to the stimulation of PRL secretion is unknown. To clarify the site(s) of ethanol action, medial basal hypothalamic deafferentation (MBHD) or medial basal hypothalamic ablation (MBHA) were performed stereotaxically in male rats, and their PRL secretory capacity in response to acute ethanol administration was compared with that of intact or sham-operated controls. In intact control rats, plasma immunoreactive PRL concentration increased markedly (P < .001 v saline injection) following ethanol 400 to 500 mg/100 g body weight (BW) intraperitoneally (IP). The PRL response was dose-related and reached a maximum plateau level at 15 minutes. Plasma PRL returned to a near-basal level by 60 minutes. The response was blocked completely (P < .001) by pretreatment with dopamine (1 mg per rat), a specific inhibitor of adenohypophyseal PRL secretion. In sham-operated rats and in MBHD and MBHA rats, ethanol (500 mg/100 g BW IP) induced a significant (P < .001 to .05) elevation of PRL relative to the respective saline treatment. The basal level was significantly (P < .005) lower in the MBHD group (5.3 +/- 0.9 ng/mL) and significantly (P < .001) higher in the MBHA group (101.1 +/- 15.7 ng/mL) than in the sham group (17.2 +/- 5.9 ng/mL). These results suggest the following: (1) acute ethanol administration stimulates PRL secretion from the pituitary in a dose-related manner, (2) ethanol appears to have direct stimulatory effects on adenohypophyseal PRL secretion, and (3) extrahypothalamic brain areas exert a stimulatory influence and the hypothalamus an inhibitory influence on basal PRL secretion.


Asunto(s)
Etanol/farmacología , Hipotálamo/efectos de los fármacos , Prolactina/metabolismo , Animales , Dopamina/farmacología , Femenino , Hipotálamo/fisiología , Masculino , Prolactina/sangre , Ratas , Ratas Wistar , Factores Sexuales
6.
Yakugaku Zasshi ; 116(9): 728-34, 1996 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-8855718

RESUMEN

Determination of volatile components in essential oils from Atractylodis plants was studied by headspace gas chromatography. The crude drug of 0.20 g with 1.0 ml of water in a capped vial was heated at 130 degrees C for 45 min. Then 0.5 ml of vaporized components were collected by gas tightsillinge, and were applied into the injection port of GC or GC/MS. Consequently we could analyze and confirm the following components; hinesol and beta-eudesmol were found to be contained in Atractylodis Lanceae Rhizoma and atractylon in Atractylodis Rhizoma. beta-Eudesmol was analyzed by headspace gas chromatography, and the obtained calibration curve showed good linearity over the range from 2.5 micrograms to 10.0 mg. The result agreed with those obtained using numerical analyses by the steam distillation method. Atractylodis was found to have a wide variety of components depending on the available sources and on the stored conditions. This method was, therefore, more rapid and simpler determination of essential oils in crude drugs using headspace gas chromatography than those used previously. The method was useful means of the analyses of components in crude drugs such as Atractylodis plants and quality control.


Asunto(s)
Cromatografía de Gases/métodos , Aceites Volátiles/análisis , Plantas Medicinales/química
7.
Anticancer Res ; 15(4): 1401-5, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7654028

RESUMEN

Growth rate of a chemically-induced colon tumor in the absence of fecal stream was investigated and the tumors to a chemotherapeutic agent tested. Eighty Sprague-Dawley rats received dimethylhydrazine (40 mg/kg) s.c. once weekly for 10 wk to induce colon cancer. Then a colostomy was performed to produce a defunctioning colon without fecal stream. 22 wk after beginning the carcinogen treatment, a barium enema was performed to visualize tumors in the defunctionalized colon. 29 rats died postoperatively and 16 had no tumor radiographically. The remaining 35 rats were divided into a control group and UFT treatment group. After 5 wk of treatment, the barium enema was repeated. The mean doubling time of 19 tumors in the control group was 9.8 days +/- 4.0 (SD). Response to UFT was judged as effective when the doubling time exceeded 17.8 days, calculated from the mean +/- 2SDs in the control group. The response rate of UFT was 48%. The growth rate of colon tumors without fecal stream was faster and more stable than those with fecal stream; as a result, the sensitivity to UFT became higher than that in tumors with fecal stream (36%), which was reported in our previous study. The present experimental system may be more accurate for assessing the response to chemotherapeutic agents.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Colon/patología , Heces , Animales , Peso Corporal , Neoplasias del Colon/tratamiento farmacológico , Masculino , Ratas , Ratas Sprague-Dawley , Tegafur/administración & dosificación , Uracilo/administración & dosificación
8.
Anticancer Res ; 14(6B): 2637-42, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7872694

RESUMEN

Chemically-induced colon cancer was used to test the sensitivity of tumors to chemotherapeutic agents. Seventy-one Sprague-Dawley rats received dimethylhydrazine (20mg/kg) s.c. once weekly for 20 weeks to induce colon cancer. Then a barium enema was performed to see the size of colon tumors. The animals were divided into three groups that were subjected to the following treatments: 5-fluorouracil (5 FU); 1-(2-tetrahydrofuryl)-5 FU(FT); and a mixture of FT and uracil (UFT). After 5 weeks of treatment, the barium enema was repeated. "Response" was assessed on the basis of tumor doubling time. Response rates in the 5-FU, FT, and UFT groups were 25%, 33% and 36%, respectively and this reflects the clinical data of these drugs. The present system may be a predictive model for screening anticancer drugs for human colorectal cancer.


Asunto(s)
Neoplasias del Colon/tratamiento farmacológico , Fluorouracilo/uso terapéutico , Tegafur/uso terapéutico , 1,2-Dimetilhidrazina , Animales , Sulfato de Bario , Carcinógenos/análisis , División Celular/efectos de los fármacos , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/diagnóstico por imagen , Neoplasias del Colon/patología , Dimetilhidrazinas/administración & dosificación , Interacciones Farmacológicas , Enema , Inyecciones Subcutáneas , Isomerismo , Masculino , Radiografía , Ratas , Ratas Sprague-Dawley , Sensibilidad y Especificidad , Uracilo/uso terapéutico
9.
Chem Pharm Bull (Tokyo) ; 42(5): 1056-62, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8069956

RESUMEN

From the air-dried roots of Glycyrrhiza glabra L. (Leguminosae) collected in Xinjiang province, China ("Shinkyo-Kanzo" in Japanese), five new flavonoid compounds named glucoliquiritin apioside (1) (a flavonone bisdesmoside), prenyllicoflavone A (5) (a bisprenylflavone), shinflavone (7) (a prenylated pyranoflavanone), shinpterocarpin (9) and 1-methoxyphaseollin (12) (both pyranopterocarpans), were isolated together with eight known saponins, seven known flavonoid glycosides, and eleven flavonoids. The structures of the new compounds have been elucidated on the basis of their chemical and physicochemical properties.


Asunto(s)
Flavonoides/aislamiento & purificación , Glycyrrhiza/química , Plantas Medicinales , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos , Flavonoides/química , Hidrólisis
10.
Eur Arch Otorhinolaryngol ; 251 Suppl 1: S68-72, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-11894780

RESUMEN

The IgE response to Cryptomeria japonica pollen antigen (CPAg) in vivo was determined by radioimmunoassay of the plasma of 525 members from 98 families with known nasal allergies. Based on responses, patients were classified into a non-responder or low-responder group (non/low) and a high-responder group. Segregation analysis revealed that the IgE non/low responsiveness to CPAg involved a single dominant trait. The gene frequency was calculated to be 0.44-0.60. The IgE non/low response to CPAg was found to be mediated by CPAg-specific suppressor T cells. These findings demonstrated that the phenotypic variation of IgE responsiveness to CPAg is not due the immune response gene, but rather is mediated by the immune suppression gene for CPAg, via CPAg-specific suppressor T cells.


Asunto(s)
Inmunoglobulina E/inmunología , Polen/efectos adversos , Rinitis Alérgica Estacional/inmunología , Adolescente , Adulto , Electroforesis en Gel de Poliacrilamida , Femenino , Frecuencia de los Genes , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Polen/genética , Radioinmunoensayo , Rinitis Alérgica Estacional/genética
11.
Res Exp Med (Berl) ; 193(4): 231-40, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8235076

RESUMEN

Portal vein infusion of aclarubicin (ACR) emulsified with Lipiodol (LP) in regenerating liver after 70% partial hepatectomy in rats was evaluated for its safety and usefulness. DNA synthesis in regenerating liver was transiently suppressed by LP, ACR or LP+ACR, but no obvious inhibition was seen in aminopyrine N-demethylase activity and liver weights. LP significantly enhanced hepatic tissue levels of ACR and its active metabolites by long-term retention in the sinusoidal space. This study demonstrates that in rats LP has a powerful effect on the long-term retention of anticancer agents in the sinusoidal space after infusion into the portal vein, without aggravating hepatic damage by anticancer agents.


Asunto(s)
Aclarubicina/administración & dosificación , Aceite Yodado/administración & dosificación , Regeneración Hepática/fisiología , Aclarubicina/farmacocinética , Aminopirina N-Demetilasa/metabolismo , Animales , ADN/biosíntesis , Replicación del ADN/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Quimioterapia Combinada , Hepatectomía , Infusiones Intravenosas , Hígado/efectos de los fármacos , Hígado/enzimología , Hígado/patología , Regeneración Hepática/efectos de los fármacos , Masculino , Vena Porta , Ratas , Ratas Wistar
12.
Cancer Res ; 52(3): 696-700, 1992 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-1732057

RESUMEN

alpha-Difluoromethylornithine (DFMO) treatment has been shown to modify carcinogenesis in many experimental tumor models, including breast, urinary bladder, and colon. This study was designed to determine whether DFMO treatment can inhibit tumor growth on chemical-induced colon cancer in rats. Effectiveness of DFMO in combination with mitomycin C (MMC) was also evaluated. Forty-two Sprague-Dawley rats received dimethylhydrazine (20 mg/kg) s.c. once weekly for 20 wk to induce colon cancer. Then a double-contrast barium enema was performed, and colon tumors were detected. The animals were divided into four groups that were subjected to the following treatment: none; DFMO alone; MMC alone; and a combination of DFMO plus MMC. After 5 wk of treatment, the barium enema was repeated. For the evaluation of treatment efficacy, tumor doubling time was adopted. The mean tumor doubling time in the control group was 20.7 +/- 9.1 days (SD). "Response" was judged as effective when tumor doubling time in treatment groups was more than 38.9 days, calculated from the mean + 2 SDs in the control group. Response rates in the DFMO, MMC, and DFMO plus MMC groups were 40.0%, 10.0%, and 82.3%, respectively. DFMO was a more effective inhibitor of tumor growth than MMC, and DFMO in combination with MMC resulted in a synergic diminution of tumor growth. The double-contrast barium enema is useful to observe sequential tumor growth and may be appropriate for the evaluation of new treatment on experimental colon cancer in rats.


Asunto(s)
Neoplasias del Colon/patología , Eflornitina/farmacología , Animales , Peso Corporal/efectos de los fármacos , División Celular/efectos de los fármacos , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/metabolismo , Dimetilhidrazinas , Masculino , Mitomicina/uso terapéutico , Putrescina/metabolismo , Ratas , Ratas Endogámicas , Espermidina/metabolismo , Espermina/metabolismo
13.
Anesthesiology ; 74(3): 412-8, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2001017

RESUMEN

The neuromuscular effects of desflurane administered alone were studied in ten healthy human volunteers aged 20-27 yr. Also, the dose-response relationships of pancuronium and succinylcholine in surgical patients during anesthesia with desflurane (n = 13) were compared to those during isoflurane anesthesia (n = 14). In the volunteers, we measured the mechanical response of the adductor pollicis muscle to stimulation of the ulnar nerve in a train-of-four (TOF) sequence at 2 Hz and at tetanic frequencies of 50, 100, and 200 Hz, each administered for 5 s. Amplitudes of the first response (T1) in each TOF sequence and the ratios of the fourth TOF response (T4) to the first were similar at 3, 6, and 9% desflurane and decreased significantly only at 12% (P less than 0.05). Desflurane concentrations of 3-12% caused tetanic fade (greater than 10% decrement in amplitude) at 50, 100, and 200 Hz. The addition of N2O and the duration of anesthetic exposure did not alter desflurane's neuromuscular effects. The only neuromuscular variable influenced by CO2 was T1 amplitude, which decreased as arterial CO2 tension (PaCO2) increased. The doses of pancuronium that depressed T1 amplitude by 50% (ED50) were similar during anesthesia with 1.25 MAC desflurane, 10.5 +/- 2.8 micrograms/kg (mean +/- SD) and 1.25 MAC isoflurane, 12.3 +/- 5.0 micrograms/kg. The ED50 doses of succinylcholine were similar during anesthesia with desflurane 132 +/- 76 micrograms/kg and isoflurane 123 +/- 36 micrograms/kg. We conclude that desflurane significantly depresses neuromuscular function and augments the action of pancuronium and succinylcholine to a degree similar to that of isoflurane.


Asunto(s)
Anestesia por Inhalación , Isoflurano/análogos & derivados , Unión Neuromuscular/efectos de los fármacos , Pancuronio/farmacología , Succinilcolina/farmacología , Adulto , Desflurano , Relación Dosis-Respuesta a Droga , Humanos , Isoflurano/administración & dosificación , Isoflurano/farmacología , Masculino , Pancuronio/administración & dosificación , Valores de Referencia , Succinilcolina/administración & dosificación , Procedimientos Quirúrgicos Operativos
14.
Urol Int ; 47(1): 25-34, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1871909

RESUMEN

The effects of electrical stimulation of hypogastric nerve and sympathetic chain on 'electroerection' (penile erection induced by electrical stimulation of the pelvic nerve) were studied in dogs to clarify the physiological roles that these neural inputs may play in producing and/or maintaining penile erection. As an objective parameter of hemodynamics of the penile circulation, the pressure in the corpus cavernosum of the penis was measured. Hypogastric nerve electrostimulation was performed in 24 dogs who had received pelvic nerve stimulation and, therefore, had 'electroerection'. Ten dogs responded to this procedure with an augmentation of 'electroerection', 10 with an attenuation of 'electroerection', and 4 with no appreciable changes. 4 out of the 10 animals who exhibited an attenuation response were then given an alpha 1-adrenergic blocker (prazosin hydrochloride) prior to the electrical stimulation to evaluate the specificity of the effects of the hypogastric nerve stimulation. In 3 of the 4 dogs the attenuation effect was abolished by this treatment and instead an augmentation effect became evident. Sympathetic chain electrostimulation was performed in 6 dogs with 'electroerection'. When applied to the L4-5 interganglionic segment, it produced a biphasic response which consisted of an initial increase followed by a decrease of the intracorporeal pressure. In contrast, stimulation of the L2-3 interganglionic segment produced a monophasic response consisting of only augmentation of the intracorporeal pressure. These data suggested that there might be two groups of fibers in the hypogastric nerve and sympathetic chain which are functioning antagonistically, and that the anti-erectile neural inputs are mediated primarily by the alpha 1-adrenergic system. To examine the sites of penile vasculature where the innervating hypogastric nerve exerts its effects, electrical pelvic/hypogastric nerve stimulations were performed in dogs in whom the inflow blood circulation to the corpora cavernosa was disrupted by arterial ligation and replaced by a constant saline infusion. It appears that the stimulatory input via the hypogastric nerve caused an increased blood flow into the cavernous space due to vasodilation of the inflow blood vessels, and the inhibitory effect occurred mainly due to relaxation of the draining blood vessels with a resultant increase of the blood outflow from the cavernous space.


Asunto(s)
Plexo Hipogástrico/fisiología , Erección Peniana/fisiología , Sistema Nervioso Simpático/fisiología , Animales , Perros , Estimulación Eléctrica , Hemodinámica/fisiología , Masculino , Erección Peniana/efectos de los fármacos , Pene/irrigación sanguínea , Pene/inervación , Prazosina/farmacología , Presión , Propranolol/farmacología , Flujo Sanguíneo Regional/fisiología
15.
Arukoru Kenkyuto Yakubutsu Ison ; 25(6): 475-85, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2085288

RESUMEN

Recently, caffeine consumption in Japan is thought to have increased. Although caffeine had been considered to be harmless, there have been studies which suggests an association between caffeine and health and give rise to vigorous discussion. However, in Japan, there have been few epidemiological studies on caffeine consumption among a general population. A questionnaire survey was conducted among medical students and the results were as follows: 1) High dose users (estimated daily caffeine use is 250 mg or more) were observed in 15.2% and the proportion was higher in males than in females. 2) The respondents gave sleepiness, dry mouth and so on, as reasons for taking caffeine beverages, and gave, as the effects of caffeine, becoming clear-headed, shaking off sleepiness, and epigastric discomfort or pain. 3) A third of respondents have experienced taking caffeine tablets and ampules to shake off sleepiness and, in males, the more caffeine they had daily, the more who reported the experience. 4) Caffeine consumption has an association with alcohol use and smoking habit among males.


Asunto(s)
Cafeína/administración & dosificación , Estudiantes de Medicina/psicología , Adulto , Bebidas , Distribución de Chi-Cuadrado , Café , Conducta de Ingestión de Líquido , Femenino , Humanos , Japón , Masculino , Fumar , Encuestas y Cuestionarios
16.
Acta Endocrinol (Copenh) ; 109(2): 145-52, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2990130

RESUMEN

A homologous radioimmunoassay was developed for rat CRF. CRF immunoreactivity was found widely in the extrahypothalamic areas in the rat central nervous system in concentrations 1-3% of that in the median eminence. Large hypothalamic lesions including the paraventricular nucleus and the median eminence did not cause a decrease in the extrahypothalamic CRF concentrations. CRF of the rat hypothalamus and cerebral cortex both consisted of high and low molecular weight forms. In contrast the posterior pituitary and the spinal cord contained only low molecular weight forms. Upon gel filtration the low molecular weight CRF of the hypothalamus co-eluted with synthetic rat CRF whereas that of the spinal cord was considerably more retarded. The low molecular weight CRF of the posterior pituitary and cerebral cortex was slightly more retarded compared to synthetic rat CRF. We conclude that CRF in many extrahypothalamic brain areas and the spinal cord does not originate from the hypothalamus and that there is some heterogeneity in the molecular form of the extrahypothalamic CRF.


Asunto(s)
Hormona Liberadora de Corticotropina/análisis , Animales , Encéfalo/metabolismo , Corteza Cerebral/análisis , Cromatografía en Gel , Hipotálamo/análisis , Hipotálamo/fisiología , Masculino , Eminencia Media/análisis , Peso Molecular , Neurohipófisis/análisis , Radioinmunoensayo , Ratas , Ratas Endogámicas , Receptores de Superficie Celular/análisis , Receptores de Hormona Liberadora de Corticotropina , Médula Espinal/análisis
17.
Toxicol Lett ; 25(2): 199-203, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-4002248

RESUMEN

The development of reflexes in neonates exposed prenatally to methylmercury and selenite was investigated. Pregnant mice were assigned to one of 4 treatments; methylmercury (MeHg), selenite(Se), combination of 2 compounds (MeHg X Se) and saline control (NaCl). Mice were injected subcutaneously (s.c.) on day 9 of gestation. The dose of each compound was 30 mumol/kg. Mercury (Hg) concentrations in the neonatal brain and liver of the MeHg X Se group were slightly lower than in the MeHg group. The results of behavioral examination revealed that the MeHg X Se group showed significantly improved development compared with the MeHg group. These facts suggest the possibility that selenium compounds have protective effects against methylmercury neurotoxicity in fetuses and neonates.


Asunto(s)
Compuestos de Metilmercurio/antagonistas & inhibidores , Efectos Tardíos de la Exposición Prenatal , Reflejo/efectos de los fármacos , Selenio/farmacología , Animales , Animales Recién Nacidos/fisiología , Encéfalo/metabolismo , Femenino , Riñón/metabolismo , Hígado/metabolismo , Mercurio/metabolismo , Compuestos de Metilmercurio/toxicidad , Ratones , Embarazo , Ácido Selenioso , Distribución Tisular
18.
Fed Proc ; 44(1 Pt 2): 183-8, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3871408

RESUMEN

Corticotropin-releasing factor B (CRF-B) is a peptide(s) isolated from bovine hypothalamic extracts by Sephadex G-100 chromatography on the basis of its ability to stimulate secretion of adrenocorticotropin (ACTH) in vitro and in vivo. It is similar in molecular size to the 41-residue ovine CRF (oCRF) or rat CRF (rCRF) recently elucidated and appears to be their bovine counterpart. Immunoreactivity of CRF-B was examined in homologous radioimmunoassays (RIAs) for oCRF or rCRF, using several anti-oCRF and anti-rCRF antibodies. CRF-B cross-reacted well with anti-oCRF antibodies but poorly with anti-rCRF antibodies. Purification of CRF-B with preparative isoelectric focusing yielded four CRF peaks, B-1 (pH 4.7), B-2 (pH 5.5), B-3 (pH 6.3), and B-4 (pH 7.0), which accounted for 16, 30, 46, and 8% of the total immunoreactivity, respectively. CRF B-2, B-3, and B-4 showed both immunological activity and biological activity in vitro (cell culture assay) and in vivo (Arimura assay), whereas CRF B-1 showed only immunoreactivity. Their relative bioactivity/immunoreactivity ratios were 0 (B-1), 1 (B-2), 1 (B-3), and 3 (B-4). All of these CRF-B subtypes exhibited RIA displacement curves parallel to that for the oCRF standard and coeluted with oCRF on Sephadex G-100 chromatography, which suggests that their molecular modifications are relatively minor.


Asunto(s)
Hormona Liberadora de Corticotropina/inmunología , Animales , Bioensayo , Bovinos , Fraccionamiento Celular , Cromatografía en Gel , Hormona Liberadora de Corticotropina/aislamiento & purificación , Hormona Liberadora de Corticotropina/farmacología , Femenino , Hipotálamo/fisiología , Conejos/inmunología , Radioinmunoensayo , Ratas , Ratas Endogámicas , Ovinos
19.
Endocrinology ; 110(6): 2074-80, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6280987

RESUMEN

Various fractions were tested in vivo for corticotropin-releasing factor (CRF) activity after Sephadex G-100 fractionation of 0.1-N HCl extracts of bovine hypophyseal stalk or cerebral cortex. Female rats pretreated with chlorpromazine, morphine, and Nembutal were used for CRF assay. CRF-A (void volume fractions; big CRF), CRF-B (Kav = 0.583), and CRF-C (salt volume fractions) of bovine hypophyseal stalk and lysine or arginine vasopressin all induced clear-cut stimulation of ACTH and corticosterone in the assay rat, whereas they were ineffective in acutely hypophysectomized rats. Control fractions purified from bovine cerebral cortex had no CRF activity. Treatment of arginine and lysine vasopressin and CRF-C with dithiothreitol and iodoacetamide completely abolished their CRF activity, whereas the CRF activities of CRF-A and CRF-B were unaltered by these treatments. Treatment with iodoacetamide alone had no effect on the CRF activity of any of these substances. Fractionation of either CRF-C or arginine vasopressin on Sephadex G-15 yielded a CRF-active peak at a Kav of 0.35. We conclude that 1) three different forms of CRF exist in bovine hypophyseal stalk; 2) CRF-A and CRF-B are unrelated to vasopressin and require neither a disulfide bond(s) nor a sulfhydryl group(s) for their CRF activity; 3) reduction of the disulfide bond of vasopressin destroys both CRF and antidiuretic activities; 4) CRF-C requires an intact disulfide bond(s) for its CRF activity and is likely to be either vasopressin itself or a substance closely related to vasopressin; and 5) CRF-B is likely to be the physiologically important form of bovine CRF.


Asunto(s)
Hormona Liberadora de Corticotropina/metabolismo , Ditiotreitol/farmacología , Hipotálamo/efectos de los fármacos , Yodoacetamida/farmacología , Yodoacetatos/farmacología , Vasopresinas/metabolismo , Hormona Adrenocorticotrópica/metabolismo , Animales , Arginina Vasopresina/metabolismo , Bovinos , Cromatografía en Gel , Corticosterona/sangre , Hipotálamo/metabolismo , Lipresina/metabolismo , Peso Molecular , Adenohipófisis/metabolismo , Ratas
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