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1.
Stud Health Technol Inform ; 217: 1009-12, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26294602

RESUMEN

Trial experiments utilized robotic pets to facilitate self-reliance in nursing home residents. A remote-control robot modeled clear and meaningful behaviors to elderly residents. Special attention was paid to its effects on mental and social domains. Employing the robot as a gaze target and center of attention created a cue to initiate a communication channel between residents who normally show no interest in each other. The Sony AIBO robot in this study uses commercially available wireless equipment, and all its components are easily accessible to any medical or welfare institution interested in additional practice of these activities.


Asunto(s)
Enfermedad de Alzheimer/psicología , Enfermedad de Alzheimer/rehabilitación , Terapia Asistida por Animales/instrumentación , Personas con Discapacidad/rehabilitación , Hogares para Ancianos , Casas de Salud , Mascotas , Robótica/instrumentación , Anciano , Animales , Atención , Comunicación , Señales (Psicología) , Perros , Diseño de Equipo , Femenino , Humanos , Masculino , Destreza Motora , Conducta Social
3.
Neurology ; 75(6): 555-61, 2010 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-20697108

RESUMEN

OBJECTIVE: To evaluate whether the pretreatment Alberta Stroke Programme Early CT Score (ASPECTS) assessed using diffusion-weighted imaging (DWI) predicts stroke outcomes at 3 months following IV recombinant tissue-type plasminogen activator (rt-PA) therapy. METHODS: Stroke patients treated with rt-PA (0.6 mg/kg alteplase) in 10 stroke centers in Japan were retrospectively studied. ASPECTS was assessed on DWI just prior to rt-PA injection. The primary outcome was a modified Rankin Scale (mRS) score of 0-2 at 3 months. Secondary outcomes included death at 3 months and symptomatic intracerebral hemorrhage (sICH) within 36 hours. RESULTS: For the 477 patients (316 men, 71 +/- 11 years old) enrolled, the median NIH Stroke Scale score was 13 (interquartile range 7-18.5), the median ASPECTS on DWI was 8 (7-10), and sICH was identified in 15 patients (3.1%). At 3 months, 245 (51.4%) had an mRS score of 0-2, and 29 (6.1%) had died. Patients with an mRS score of 0-2 had higher median ASPECTS (9; interquartile range 8-10) than other patients (8; 6-9, p < 0.001). Using receiver operating characteristic curves, the optimal cutoff ASPECTS to predict an mRS score of 0-2 was > or =7. On multivariate regression analysis, ASPECTS > or =7 was related to an mRS score of 0-2 (odds ratio 1.85; 95% confidence interval 1.07-3.24), ASPECTS < or =4 was related to death (3.61; 1.23-9.91), and ASPECTS < or =5 was related to sICH (4.74; 1.54-13.64). CONCLUSION: ASPECTS on DWI was independently predictive of functional and vital outcomes at 3 months, as well as sICH within 36 hours, following rt-PA therapy for stroke patients.


Asunto(s)
Fibrinolíticos/administración & dosificación , Sistema de Registros , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/tratamiento farmacológico , Activador de Tejido Plasminógeno/administración & dosificación , Anciano , Anciano de 80 o más Años , Femenino , Fibrinolíticos/uso terapéutico , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos , Accidente Cerebrovascular/epidemiología , Activador de Tejido Plasminógeno/uso terapéutico , Resultado del Tratamiento
4.
AJNR Am J Neuroradiol ; 30(6): 1268-9, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19213827

RESUMEN

The frontal bone window (FBW) is a promising approach in evaluating the anterior cerebral artery. The goal of the present study was to determine the rates of detection of the basal cerebral arteries by using the FBW alone and a combination of the FBW with the temporal bone window (TBW) in 163 patients. The combined application improved detection rates of A1 (58.6% versus 46.0%, P = .001) and A2 (43.6% versus 6.7%, P < .001) compared with the TBW alone.


Asunto(s)
Arteria Cerebral Anterior/diagnóstico por imagen , Ecoencefalografía/métodos , Ecoencefalografía/estadística & datos numéricos , Aumento de la Imagen/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/epidemiología , Ultrasonografía Doppler en Color/métodos , Ultrasonografía Doppler en Color/estadística & datos numéricos , Anciano , Femenino , Humanos , Japón/epidemiología , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
Inflamm Bowel Dis ; 7(3): 221-5, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11515848

RESUMEN

OBJECTIVES: Oral 5-aminosalicylic acid (5-ASA) preparations have been used frequently in the treatment of ulcerative colitis. However, there have been few reports investigating the relationship between colonic mucosal concentrations of 5-ASA and its clinical efficacy when oral sulfasalazine or 5-ASA compounds were administered. The aim of this study is to compare the mucosal concentrations of 5-ASA ensured by sulfasalazine or mesalamine, and to define the clinical significance of the measurement of 5-ASA concentrations in the treatment of distal ulcerative colitis. MATERIALS AND METHODS: Biopsies were taken from the rectum and sigmoid colon of the oral sulfasalazine group (n = 13) and the slow-release 5-ASA (mesalamine) group with (n = 5) or without (n = 11) rectal administration of 5-ASA. High-pressure liquid chromatography was used to measure the tissue concentrations of 5-ASA and its metabolites. We compared the 5-ASA concentrations of the sulfasalazine group with the mesalamine group. Furthermore, we analyzed the relationship between tissue 5-ASA concentrations and the Disease Activity Index (DAI). RESULTS: The concentrations of 5-ASA and acetyl-5-ASA in the sulfasalazine group were higher than those in the group taking oral mesalamine alone (p < 0.01). The concentration of 5-ASA was much higher in the patients who received oral and rectal mesalamine in an enema than in the patients who had oral mesalamine alone. There was a significant inverse correlation between the DAI and concentrations of 5-ASA in the rectum (r = 0.712, p < 0.001). CONCLUSIONS: We demonstrated that the colonic mucosal concentration of 5-ASA was significantly higher in the sulfasalazine group than in the mesalamine group. Furthermore, the concentrations of mucosal 5-ASA may be a good marker for the estimation of its efficacy in the treatment of ulcerative colitis.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Mucosa Intestinal/metabolismo , Mesalamina/uso terapéutico , Sulfasalazina/uso terapéutico , Administración Oral , Adulto , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/farmacología , Femenino , Humanos , Mucosa Intestinal/efectos de los fármacos , Masculino , Mesalamina/administración & dosificación , Mesalamina/farmacología , Persona de Mediana Edad , Sulfasalazina/administración & dosificación , Sulfasalazina/farmacología , Resultado del Tratamiento
7.
Am J Gastroenterol ; 96(4): 1123-6, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11316158

RESUMEN

OBJECTIVES: Studies in the US and Europe have shown that appendectomy may prevent the development of ulcerative colitis, but no detailed study has been conducted in Japan, where ulcerative colitis is uncommon and the population is racially homogeneous. In addition, there has been no detailed analysis of the relationship between appendectomy and the clinical course of ulcerative colitis. In this multicenter clinical study, we evaluated the effects of appendectomy on ulcerative colitis in Japan. METHODS: A case-control study was undertaken in seven medical institutions comparing the incidence of appendectomy and tonsillectomy in 325 patients with ulcerative colitis and 325 controls matched for age (10-yr intervals) and sex. Disease duration, extent, and prognosis were determined in 21 patients with ulcerative colitis who underwent appendectomies and 304 patients with ulcerative colitis who did not undergo appendectomies. RESULTS: Appendectomy was performed in a significantly lower percentage of patients in the ulcerative colitis group (21/325, 6.5%) than in the control group (53/325, 16.3%) (p < 0.001) (odds ratios = 0.355, 95% CI = 0.208-0.603). In contrast, no significant difference was observed between the groups with respect to tonsillectomy. The mean age (25.7 +/- 10.9 yr) of patients with ulcerative colitis at the time of appendectomy was significantly higher than the mean age (20.1 +/- 8.7 yr) of patients in the control group at the time of appendectomy (p < 0.05). The incidence of proctitis was higher in the appendectomy group than in the group that did not undergo appendectomies (38.1% vs 18.1%). In addition, the recurrence rates were significantly lower in the appenectomy group than in the group that did not undergo appendectomies (57. 1% vs 78.6%, p < 0.05), although both groups were similar in composition as to sex, age, duration of disease, smoking status, and previous medical treatment. CONCLUSIONS: Our results indicate that appendectomy has a negative association with and perhaps a preventive effect on the development of ulcerative colitis in the Japanese population. Furthermore, appendectomy also appears to reduce the extent and recurrence of ulcerative colitis.


Asunto(s)
Apendicectomía , Colitis Ulcerosa/prevención & control , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Recurrencia , Tonsilectomía
8.
Nihon Shokakibyo Gakkai Zasshi ; 98(2): 151-6, 2001 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-11235189

RESUMEN

The efficacy and safety of mesalamine enema were examined in 20 patients with steroid-resistant or dependent, distal ulcerative colitis. Rectal bleeding disappeared in 3 (18%). 8 (50%) of 16 patients within 2 weeks and 4 weeks after the start of mesalamine enema treatment, respectively. Mean clinical activity index (CAI) score after the treatment was significantly reduced (8.1-->3.6, p < 0.001). Furthermore, Mean doses of oral corticosteroid after the treatment (7.3 mg) were also significantly lower than those before the treatment (12.8 mg) (p < 0.01). Four patients dropped out. Three patients could not retain the enemas because of abdominal discomfort and one patient had fever and rash. There were no significant differences in age, gender, disease duration, disease type, and mean doses of oral corticosteroid before the treatment between the response group (n = 8) and the non-response group (n = 8). However, clinical and endoscopic activities before mesalamine enema treatment in the non-response group (CAI 9.8, Matts score 8.0) were higher than those in the response group (CAI 6.4, Matts score 5.5). These results suggest that mesalamine enema is useful for mildly to moderately active distal ulcerative colitis by improving clinical symptoms and reducing corticosteroid.


Asunto(s)
Antiinflamatorios/administración & dosificación , Colitis Ulcerosa/tratamiento farmacológico , Enema , Mesalamina , Prednisolona/administración & dosificación , Adolescente , Corticoesteroides/administración & dosificación , Adulto , Colitis Ulcerosa/diagnóstico , Resistencia a Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad
9.
Opt Lett ; 26(20): 1538-40, 2001 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-18049655

RESUMEN

A novel method of optical phase-shift detection using differential-phase-to-intensity conversion (DPIC) based on injection locking of a semiconductor laser is proposed. We predict DPIC numerically and verify it experimentally. We then demonstrate detection of OC-48 (2.48832-Gbit/s) phase-modulated signals by use of DPIC.

10.
J Cardiovasc Pharmacol Ther ; 6(4): 363-7, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11907638

RESUMEN

BACKGROUND: The concurrent use of amiodarone and warfarin inhibits metabolism of S-warfarinby cytochrome P450 (CYP) 2C9, thereby increasing the anticoagulant effect of warfarin. Amiodarone primarily inhibits CYP1A2 and CYP3A4, and desethylamiodarone primarily inhibits CYP2C9. We investigate whether a relationship exists between the plasma concentration of desethylamiodarone and anticoagulation when amiodarone is administered to patients receiving warfarin therapy. METHODS AND RESULTS: The correlation between the plasma concentration of either amiodarone or desethylamiodarone, and prolongation of prothrombin time-international normalized ratio/dose of warfarin (Delta INR/Dose) on day 7 of amiodarone administration was studied in 25 patients (22-74 years old) with structural heart disease and refractory arrhythmias receiving stable warfarin therapy. RESULTS: No correlation was found between the plasma concentration of amiodarone and Delta INR/Dose, but a correlation was found between the plasma concentration of desethylamiodarone and Delta INR/Dose. CONCLUSIONS: It was suggested that inhibition of CYP2C9 by desethylamiodarone, the active metabolite of amiodarone, plays an important role in the interaction of warfarin and amiodarone.


Asunto(s)
Amiodarona/análogos & derivados , Amiodarona/farmacología , Anticoagulantes/farmacología , Anticoagulantes/uso terapéutico , Cardiopatías/tratamiento farmacológico , Warfarina/metabolismo , Warfarina/farmacología , Adulto , Anciano , Amiodarona/sangre , Amiodarona/uso terapéutico , Anticoagulantes/administración & dosificación , Anticoagulantes/metabolismo , Interacciones Farmacológicas , Quimioterapia Combinada , Femenino , Cardiopatías/sangre , Humanos , Relación Normalizada Internacional , Masculino , Persona de Mediana Edad , Warfarina/administración & dosificación , Warfarina/uso terapéutico
11.
Gastroenterology ; 119(6): 1514-23, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11113073

RESUMEN

BACKGROUND & AIMS: Crohn's disease (CD) is characterized by a marked accumulation of activated Th1 type CD4(+) T cells and macrophages in inflamed intestinal mucosa. Interleukin (IL)-18 is a recently described cytokine that mainly exists in activated macrophages and shares biological activities with IL-12 in driving the development of Th1 type CD4(+) T cells by inducing interferon gamma. To clarify the role of IL-18 in intestinal inflammation in CD, we assessed the functional role of IL-18 in regulating intestinal mucosal lymphocytes. METHODS: Serum IL-18 concentration was measured by enzyme-linked immunosorbent assay. Expression of IL-18 and IL-18 receptor in human intestinal mucosa was determined using immunohistochemistry and flow cytometry. The functional activity of IL-18 was assessed by the use of recombinant IL-18 to stimulate both the growth of intestinal mucosal lymphocytes and IL-2 receptor induction activity. RESULTS: The serum IL-18 concentration was significantly higher in patients with CD than normal controls. In the inflamed colonic mucosa of CD, many IL-18(+)CD68(+) macrophages had infiltrated the lamina propria. Intestinal mucosal lymphocytes from CD expressed functional IL-18 receptors. Recombinant IL-18 induced significant proliferative responses in freshly isolated mucosal lymphocytes from CD patients, but not from normal controls. IL-18 up-regulated IL-2 receptor expression in mucosal lymphocytes from patients with CD, but not from normal controls. CONCLUSIONS: These findings suggest that infiltrated macrophages in the inflamed intestinal mucosa in CD produce IL-18, and that macrophage-derived IL-18 may serve as a potent regulatory factor for intestinal mucosal lymphocytes, thereby contributing to chronic intestinal inflammation in CD.


Asunto(s)
Enfermedad de Crohn/patología , Interleucina-18/fisiología , Mucosa Intestinal/patología , Linfocitos/patología , División Celular/fisiología , Membrana Celular/metabolismo , Enfermedad de Crohn/metabolismo , Humanos , Interleucina-18/metabolismo , Subunidad alfa del Receptor de Interleucina-18 , Mucosa Intestinal/metabolismo , Receptores de Interleucina/metabolismo , Receptores de Interleucina-18 , Valores de Referencia , Distribución Tisular
12.
Am J Gastroenterol ; 95(10): 2848-51, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11051358

RESUMEN

OBJECTIVE: Much remains unknown about the pathogenesis of intestinal Behçet's disease. The majority of these patients are treated with surgical intervention, although it has been recently reported that a number of medical treatments are sometimes effective. Only few studies, however, have ever been undertaken to analyze the long-term prognosis of this disease. In this study, we analyzed the clinical course and the recurrences after initial therapy in patients with intestinal Behçet's disease. METHODS: We investigated 20 patients (surgical group, n = 8; nonsurgical group, n = 12) for whom the clinical courses were known for > or = 2 yr (2-23 yr). RESULTS: The surgical group tended to have higher rates of complications such as ocular and ileal lesions than the nonsurgical group. In the surgical group, 75% of the patients recurred (and were readmitted) within 2 yr, and 37.5% of the patients required reoperation for intestinal obstruction because of ulcer at the anastomosis. The percentage of peripheral CD8+ DR+ lymphocytes in the recurrent group (10.4% +/- 2.5%) was significantly higher than that in the nonrecurrent group (4.3% +/- 1.2%, p < 0.05). CONCLUSIONS: Our results indicate that more extensive disease involving the ileum and ocular lesions are markers of severity and progression to surgical crisis, and that patients requiring surgery suffer more frequent recurrences. Furthermore, an increased percentage of peripheral CD8+ DR+ lymphocytes may be a risk factor for disease recurrence.


Asunto(s)
Síndrome de Behçet/diagnóstico , Enfermedades Intestinales/diagnóstico , Adolescente , Adulto , Síndrome de Behçet/cirugía , Femenino , Estudios de Seguimiento , Humanos , Enfermedades Intestinales/cirugía , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/cirugía , Recurrencia , Reoperación
13.
J Toxicol Sci ; 25(1): 17-24, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10736786

RESUMEN

The activity of ultraviolet (UV) light to induce unscheduled DNA synthesis (UDS) was investigated in hairless mouse epidermis by means of an in vivo-in vitro assay using a liquid scintillation counting method. Groups of three to five 8-week-old female hairless mice were irradiated with UV-B or UV-A, then skin samples were taken and cultured individually in medium containing [3H]thymidine with or without hydroxyurea (HU) for 2 hr. DNA of the epidermis was extracted, and incorporation of [3H]thymidine and the DNA content were determined with a liquid scintillation counter and a fluorescence spectrophotometer, respectively. Induction of UDS was judged in terms of the UDS index [(the ratio of DNA synthesis in the presence of HU to that in its absence) x 100]. UV-B increased the UDS index 1 hr after irradiation of 500 J/m2, which corresponds to approximately 1 minimal erythema dose or 1 minimal edema dose, and showed a dose-dependent increase up to 17-fold in the UDS index at irradiation doses of 500 to 2,000 J/m2. In a time-course study, UV-B also increased replicative DNA synthesis (RDS) 48 hr after irradiation at 1,000 J/m2. On the other hand, UV-A did not increase the UDS index at irradiation doses of 2 x 10(5) to 8 x 10(5) J/m2. These results show that induction of UDS by UV irradiation depends on wavelength and an increase of RDS in the epidermis exposed to UV-B irradiation appears after induction of UDS.


Asunto(s)
ADN/efectos de la radiación , Epidermis/efectos de la radiación , Rayos Ultravioleta/efectos adversos , Animales , ADN/biosíntesis , ADN/efectos de los fármacos , Daño del ADN , Relación Dosis-Respuesta en la Radiación , Edema/etiología , Epidermis/efectos de los fármacos , Eritema/etiología , Femenino , Hidroxiurea/farmacología , Ratones , Ratones Pelados , Factores de Tiempo
15.
J Invest Dermatol ; 112(1): 19-24, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9886258

RESUMEN

Although ultraviolet B (UVB) irradiation induces local immune or systemic immune suppression, depending on the dose, the immune suppression by ultraviolet A (UVA) has not been fully investigated. In this study, we investigated the effect of UVA on the immune response in vitro and in vivo. The effect of UVA on the antigen-presenting function of epidermal cells was measured in terms of antigen-specific T cell proliferation. A murine epidermal cell suspension was exposed to UVA in vitro, pulsed with trinitrobenzenesulfonic acid, and cultured with T cells prepared from syngeneic mice previously sensitized with trinitrochlorobenzene. UVA (5-20 J per cm2) suppressed the antigen-presenting function of epidermal cells in a dose-dependent manner, accompanied with suppression of the expression of costimulatory molecules on Langerhans cells. In order to investigate the effect of an antioxidant on the immune suppression, an epidermal cell suspension was irradiated with UVA in the presence or absence of glutathione. The suppressions of antigen-presenting function and ICAM-1 expression were significantly prevented by glutathione in a dose-dependent manner. Further, the effect of UVA on the immune response at the induction phase of contact hypersensitivity was evaluated in terms of lymph node cell proliferation ex vivo. UVA irradiation suppressed the endogenous proliferation of lymph node cells in trinitrochlorobenzene-painted mice, and this suppression was significantly reversed by the application of glutathione to the skin during irradiation. These results suggest that UVA-induced immune suppression may be mediated by reactive oxygen species, at least in part.


Asunto(s)
Tolerancia Inmunológica/efectos de la radiación , Especies Reactivas de Oxígeno , Rayos Ultravioleta , Animales , Presentación de Antígeno/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Femenino , Glutatión/farmacología , Molécula 1 de Adhesión Intercelular/biosíntesis , Queratinocitos/efectos de la radiación , Activación de Linfocitos , Ratones , Ratones Endogámicos C3H
16.
Rev Lat Am Enfermagem ; 7(4): 75-81, 1999 Oct.
Artículo en Portugués | MEDLINE | ID: mdl-12040569

RESUMEN

The present study was carried out at the Municipalities of São Paulo and Guarulhos with undergraduate nursing students and aimed at evaluating their knowledge regarding neonatal nursing and, if necessary, to contribute to the program reformulation. Thus, we would be able to improve nurses knowledge on the full-term new born care. In order to develop a structured questionnaire to be used as an instrument to measure the studied variable, aspects of the theoretical content related to the most common care procedures at the neonatal unit were selected. Authors found that students' theoretical knowledge on the theme was regular.


Asunto(s)
Competencia Clínica , Enfermería Neonatal/educación , Humanos , Recién Nacido , Encuestas y Cuestionarios
17.
J Dermatol ; 25(4): 211-21, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9609977

RESUMEN

To investigate the characteristics of the proliferation and differentiation of epidermal melanocytes in F1 hairless mice of HR-1 x HR/De parents in vitro, cell suspensions of the neonatal epidermis were cultured in a serum-free medium supplemented with dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP) and/or basic fibroblast growth factor (bFGF). The differentiation of melanocytes was induced by treatment with DBcAMP. In contrast, the sustained proliferation of melanoblasts was induced by combined treatment with DBcAMP and bFGF. The melanoblasts could be subcultured in serum-free medium supplemented with the two factors in the presence of keratinocytes, but not in their absence. This is the first report of successful culture of melanoblasts and melanocytes from hairless mice; it is expected to be useful in understanding the mechanism of the development of pigmented spots in the epidermis of (HR-1 x HR/De)F1 mice, which are reported to be induced by repeated exposure to ultraviolet light B.


Asunto(s)
Células Epidérmicas , Queratinocitos/citología , Melanocitos/citología , Ratones Pelados , Animales , Animales Recién Nacidos , Bucladesina/farmacología , Diferenciación Celular , División Celular/efectos de los fármacos , Células Cultivadas/citología , Medios de Cultivo , Femenino , Factores de Crecimiento de Fibroblastos/farmacología , Humanos , Recién Nacido , Queratinocitos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía de Contraste de Fase , Valores de Referencia , Especificidad de la Especie
18.
Biophys J ; 74(2 Pt 1): 892-8, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9533700

RESUMEN

Formation of the inverted hexagonal (H(II)) phase from the lamellar (L(alpha)) phase of bovine brain-extracted phosphatidylcholine (BBPC) and phosphatidylethanolamine (BBPE) was investigated using 31P-NMR with or without cholesterol. When the ratio of BBPC to BBPE was 1:1, the H(II) formation was observed in the presence of 33 mol% cholesterol (i.e., BBPC:BBPE:cholesterol = 1:1:1) at 47 degrees C. The fraction of the H(II) phase in the BBPC/BBPE/cholesterol system could be controlled by the addition of dioleoylglycerol. The change of molecular motion of cholesterol affected by the H(II) formation was measured at various ratios of the L(alpha) to H(II) phase with the time-resolved fluorescence depolarization method, using dehydroergosterol as a fluorescent probe. It is observed that the motion of cholesterol became vigorous in the mixture state of the L(alpha) and the H(II) phases compared to that in the L(alpha) or the H(II) phase only. These facts show that cholesterol has the strong ability to induce the H(II) phase, probably by special molecular motion, which includes change of its location from the headgroup area to the acyl-chain area.


Asunto(s)
Colesterol/química , Liposomas/química , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Animales , Química Encefálica , Bovinos , Diglicéridos , Polarización de Fluorescencia , Modelos Moleculares , Conformación Molecular , Resonancia Magnética Nuclear Biomolecular , Fosfatidilcolinas/aislamiento & purificación , Fosfatidiletanolaminas/aislamiento & purificación , Fósforo , Factores de Tiempo
19.
J Photochem Photobiol B ; 47(2-3): 136-41, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10093913

RESUMEN

We have studied the effect of a plasmin inhibitor, trans-4-aminomethylcyclohexanecarboxylic acid (trans-AMCHA), on skin pigmentation induced by ultraviolet (UV) exposure in Weiser-Maples guinea pigs. When guinea pigs are exposed to UV radiation (840 mJ cm-2), skin pigmentation is clearly observed from seven days after exposure and continued to increase to 29 days. Post-exposure applications of 2 and 3% solutions of trans-AMCHA to the exposed regions prevent or inhibit the pigmentation process. When the skin is removed and stained by the Fontana-Masson method, melanin content in the basal layer of UV-exposed epidermis is significantly reduced in the regions to which 2 and 3% trans-AMCHA solutions have been applied, compared with the vehicle control. As plasmin is known to contribute to the release of arachidonic acid (AA) and the production of prostaglandins (PGs), we have examined the effects of trans-AMCHA on AA-induced pigmentation in guinea pig skin. Topical application of trans-AMCHA causes a dose-dependent decrease in AA-induced pigmentation. These results suggest that trans-AMCHA reduces melanocyte tyrosinase activity by suppressing the production of PGs, UV-induced melanogens, through the suppression of the UV-induced increase in epidermal plasmin activity.


Asunto(s)
Antifibrinolíticos/farmacología , Pigmentación de la Piel , Ácido Tranexámico/farmacología , Administración Tópica , Animales , Antifibrinolíticos/química , Ácido Araquidónico/farmacología , Cobayas , Masculino , Melaninas , Estructura Molecular , Piel/efectos de los fármacos , Piel/patología , Piel/efectos de la radiación , Pigmentación de la Piel/efectos de la radiación , Ácido Tranexámico/química , Rayos Ultravioleta
20.
J Dermatol Sci ; 14(3): 199-206, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9138477

RESUMEN

We examined how and to what extent the constitution of melanin and the expression, as well as the activity, of melanosomal proteins influence the production of melanin pigment by human black and light brown melanocytes, Mel (b) cells and Mel (l) cells, respectively. Melanin pigment in Mel (b) and Mel (l) cells consisted of a mixture of eumelanin and pheomelanin, and Mel (b) cells contained a larger amount. The signal intensity ratio of eumelanin to pheomelanin was similar in both cell types, though the two cell types differed in appearance. Tyrosinase activity and the amount of tyrosinase-related protein (TRP-1) of Mel (b) cells were higher than those of Mel (l) cells. Dopachrome tautomerase (DCT) activity and the amount of 6H5MICA were reduced in Mel (b) cells in comparison with Mel (l) cells. No significant difference in DHICA-converting activity or catechol-O-methyltransferase activity was found between Mel (b) and Mel (l) cells. There was no correlation between DHICA-converting activity and amount of TRP-1. These results suggest that the difference in the pigmentation of the two human melanocyte cell lines, Mel (b) and Mel (l), is derived from differences in the activity and expression of tyrosinase, TRP-1 and DCT, which affect the content and constitution of melanin polymers.


Asunto(s)
Pueblo Asiatico/genética , Población Negra/genética , Oxidorreductasas Intramoleculares , Melaninas/metabolismo , Melanocitos/metabolismo , Glicoproteínas de Membrana , Pigmentación de la Piel/genética , Población Blanca/genética , Northern Blotting , Catecol O-Metiltransferasa/análisis , Catecol O-Metiltransferasa/genética , Catecol O-Metiltransferasa/metabolismo , Células Cultivadas , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia por Spin del Electrón , Citometría de Flujo , Regulación de la Expresión Génica , Humanos , Recién Nacido , Isomerasas/análisis , Isomerasas/genética , Isomerasas/metabolismo , Masculino , Melaninas/análisis , Melaninas/genética , Melanocitos/química , Melanocitos/citología , Monofenol Monooxigenasa/análisis , Monofenol Monooxigenasa/genética , Monofenol Monooxigenasa/metabolismo , Oxidorreductasas/análisis , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Proteínas/análisis , Proteínas/genética , Proteínas/metabolismo , ARN Mensajero/análisis , ARN Mensajero/genética , ARN Mensajero/metabolismo , Pigmentación de la Piel/fisiología
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