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1.
Clin Exp Allergy ; 48(4): 379-393, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29288569

RESUMEN

BACKGROUND: Gender disparities in adult patients with asthma regarding its prevalence and severity are mainly due to enhanced type 2 T-helper (Th2) cytokine production in female patients compared to that in male patients. However, the pathways mediating this effect remain unclear. OBJECTIVE: We aimed to determine the roles of two major subsets of dendritic cells (DCs) in females, specifically those displaying CD11b or CD103, during enhanced Th2 priming after allergen exposure, using an ovalbumin-induced asthma mouse model. METHODS: Sex-based differences in the number of DCs at inflamed sites, costimulatory molecule expression on DCs, and the ability of DCs to differentiate naïve CD4+ T cells into Th2 population were evaluated after allergen exposure in asthmatic mice. In addition, we assessed the role of 17ß-oestradiol in CD103+ DC function during Th2 priming in vitro. RESULTS: The number of CD11bhigh DCs and CD103+ DCs in the lung and bronchial lymph node (BLN) was increased to a greater extent in female mice than in male mice at 16 to 20 hours after ovalbumin (OVA) inhalation. In BLNs, CD86 and I-A/I-E expression levels and antigen uptake ability in CD103+ DCs, but not in CD11bhigh DCs, were greater in female mice than in male mice. Furthermore, CD4+ T cells cultured with CD103+ DCs from female mice produced higher levels of interleukin (IL)-4, IL-5, and IL-13, compared with CD4+ T cells cultured with CD103+ DCs from male mice. The 17ß-oestradiol-oriented enhancement of CD86 expression on CD103+ DCs after allergen exposure induced the enhanced IL-5 production from CD4+ T cells. CONCLUSIONS AND CLINICAL RELEVANCE: These findings suggest that with regard to asthma, enhanced Th2 cytokine production in females might be attributed to 17ß-oestradiol-mediated Th2-oriented CD103+ DCs in the BLN.


Asunto(s)
Asma/inmunología , Células Dendríticas/inmunología , Hipersensibilidad/inmunología , Caracteres Sexuales , Animales , Antígenos CD/inmunología , Citocinas/biosíntesis , Estradiol/inmunología , Femenino , Cadenas alfa de Integrinas/inmunología , Activación de Linfocitos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Células Th2/inmunología
2.
Sci Rep ; 7(1): 13450, 2017 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-29044178

RESUMEN

The progress of caries has conventionally been evaluated by checking changes in mineral density using transverse microradiography (TMR). Recent advances have seen development of a new measurement system, using in-air micro proton induced X-ray/gamma-ray emission (PIXE/PIGE). PIXE/PIGE enables analysis of distributions and concentrations of multiple mineral elements in a carious lesion. The aim of this study was to evaluate the effectiveness of PIXE/PIGE for investigating the development of root caries. In summary, we successfully established a multi-elemental sequential measuring method using in-air micro-PIXE/PIGE to identify the dynamic distributions and concentrations of Ca and F in human root dentin. The PIXE/PIGE potentially offers a useful advantageous technique for studying carious development by using as a combination with conventional techniques such as TMR and Micro-computed tomography (µCT).


Asunto(s)
Calcio/análisis , Rayos gamma , Radiografía Dental , Caries Radicular/diagnóstico por imagen , Rayos X , Humanos , Minerales , Radiografía Dental/métodos , Caries Radicular/metabolismo , Caries Radicular/patología , Desmineralización Dental/diagnóstico por imagen , Desmineralización Dental/metabolismo , Desmineralización Dental/patología
3.
Diabetes Obes Metab ; 17(11): 1033-41, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26094974

RESUMEN

AIMS: To evaluate the efficacy and tolerability of sitagliptin in subjects with impaired glucose tolerance (IGT). METHODS: In a double-blind, parallel-group study, 242 Japanese subjects with IGT, determined by a 75-g oral glucose tolerance test (OGTT) at week -1, were randomized (1 : 1 : 1) to placebo (n = 83), sitagliptin 25 mg (n = 82) or 50 mg (n = 77) once daily for 8 weeks. Glycaemic variables were assessed using another OGTT at week 7 and meal tolerance tests (MTTs) at weeks 0 and 8. Primary and secondary endpoints were percent change from baseline in glucose total area under the curve 0-2 h (AUC(0 -2 h)) during the MTT and OGTT, respectively. RESULTS: Least squares mean percent change from baseline in glucose AUC(0 -2 h) during the MTT were -2.4, -9.5 and -11.5%, and during the OGTT were -3.7, -21.4 and -20.1% with placebo, sitagliptin 25 mg once daily, and 50 mg once daily, respectively (p < 0.001 for either sitagliptin dose vs placebo in both tests). Sitagliptin treatment enhanced early insulin response during the OGTT and decreased total insulin response, assessed as the total AUC(0 -2 h) during the MTT. Sitagliptin treatment also suppressed glucagon response during the MTT. The incidence of adverse events, including hypoglycaemia, was low and generally similar in all treatment groups. CONCLUSIONS: Treatment with sitagliptin significantly reduced glucose excursions during both an MTT and an OGTT; this effect was associated with an increase in early insulin secretion after oral glucose loading as well as a blunted glucagon response during an MTT. Sitagliptin was generally well tolerated in subjects with IGT.


Asunto(s)
Glucemia/efectos de los fármacos , Intolerancia a la Glucosa/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Periodo Posprandial/efectos de los fármacos , Fosfato de Sitagliptina/administración & dosificación , Anciano , Glucemia/metabolismo , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Prueba de Tolerancia a la Glucosa , Carga Glucémica/efectos de los fármacos , Humanos , Insulina/sangre , Japón , Masculino , Comidas , Persona de Mediana Edad
4.
Transplant Proc ; 44(1): 134-6, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22310597

RESUMEN

This report presents a falsely abnormally elevated blood trough concentration (C(t)) of tacrolimus measured by antibody-conjugated magnetic immunoassay (ACMIA) methods in a renal transplant recipient. Because the C(t) of tacrolimus was 78.5 ng/mL at day 2 after a 52-year-old man underwent renal transplantation, we stopped the tacrolimus extended-release formulation. However, because the abnormally elevated blood C(t) continued in the range of 41.1-59.1 ng/mL, we then measured the tacrolimus concentration in a stored blood sample before renal transplantation, it was 43 ng/mL. Consequently, the day-7 blood sample was measured with both ACMIA and enzyme-linked immunoassay, showing C(t) values of 42.8 ng/mL and 0.89 ng/mL, respectively. Because the abnormally elevated C(t) was falsely measured by the ACMIA method, we restarted tacrolimus However, the calcineurin inhibitor was subsequently converted to cyclosporine at day 21 after renal transplantation. Although cyclosporine was also measured by ACMIA, there was not an abnormally elevated C(t). Subsequently, the tacrolimus concentration ratio in plasma and whole blood (P/B-tacrolimus concentration ratio) was measured by ACMIA in a posttacrolimus blood sample. The P/B-tacrolimus concentration ratio was 100%. In contrast, the P/B-tacrolimus concentration ratio was <30% in 2 control patients administered tacrolimus. It has been reported recently that there were cases showing falsely slightly elevated C(t) of tacrolimus within the therapeutic range of concentrations. Therefore, we must be careful not to reduce the tacrolimus dose falsely. We consider confirmatory methods for a falsely abnormally elevated C(t) of tacrolimus measured by ACMIA to (1) measure P/B-tacrolimus concentration ratio, (2) compare ACMIA with another measurement, and (3) evaluate a blood sample stored before tacrolimus administration.


Asunto(s)
Monitoreo de Drogas/métodos , Inmunoensayo , Inmunosupresores/sangre , Trasplante de Riñón , Magnetismo , Tacrolimus/sangre , Ciclosporina/administración & dosificación , Sustitución de Medicamentos , Quimioterapia Combinada , Técnica de Inmunoensayo de Enzimas Multiplicadas , Ensayo de Inmunoadsorción Enzimática , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/farmacocinética , Trasplante de Riñón/inmunología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Tacrolimus/administración & dosificación , Tacrolimus/farmacocinética , Resultado del Tratamiento
5.
J Hosp Infect ; 73(1): 24-33, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19640607

RESUMEN

Microbial surveillance of environmental bacteria was performed in order to study the microbial changes in a newly established hospital building. Airborne bacteria and surface-associated bacteria on floors and sinks were systematically collected between 2002 and 2005. The number of isolates obtained from frequently used floors was significantly higher than that obtained from those floors used less often. A significant increase in Staphylococcus aureus, the appearance of Pseudomonas aeruginosa, and changes among species of Gram-negative bacilli were observed 8-11 months after the new building had been opened. Furthermore, pulsed-field gel electrophoresis (PFGE) typing of meticillin-resistant S. aureus (MRSA) and P. aeruginosa showed that strains of the same PFGE groups were isolated from different sinks, floors and the adjoining old buildings. The number of MRSA isolates obtained from the new building increased as time passed. The sinks from which P. aeruginosa strains of the same PFGE type were isolated are connected by the same drainage pipe. Human movement has considerable effects on bacterial flora and their subsequent spread.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Biodiversidad , Microbiología Ambiental , Hospitales , Bacterias/genética , Técnicas de Tipificación Bacteriana , Análisis por Conglomerados , Dermatoglifia del ADN , Electroforesis en Gel de Campo Pulsado , Genotipo , Humanos , Estudios Longitudinales , Prevalencia
7.
J Dent Res ; 87(8): 762-6, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18650549

RESUMEN

The flexural strength of Type I collagen, the major organic component of human dentin, increases with heat. We hypothesized that human dentin can be strengthened by heating, which may help prevent fracture of non-vital teeth after restoration. Beam-shaped dentin specimens were obtained from the crowns of human third molars. The dentinal tubular orientations were arranged to run parallel or perpendicular to loading surfaces. The flexural and microtensile strengths of dentin in the parallel specimens were 2- to 2.4-fold greater after being heated between 110 degrees C and 140 degrees C for 1 hr. The stress intensity factors at fracture also increased after specimens were heated. The x-ray diffraction analyses suggested that shrinking of the lateral packing of the collagen triple-helices from 14 A to 11 A was the probable cause of the strengthening of heated dentin. We conclude that heat treatment strengthens human dentin.


Asunto(s)
Análisis del Estrés Dental , Dentina/química , Calor , Diente Molar/química , Análisis de Varianza , Desecación , Humanos , Técnicas In Vitro , Estrés Mecánico , Resistencia a la Tracción
8.
Eur J Anaesthesiol ; 25(10): 805-9, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18538052

RESUMEN

BACKGROUND AND OBJECTIVE: To investigate the effect of urinary flow rate on the urinary bladder temperature, we compared the accuracy and precision of urinary bladder temperature with oesophageal temperature at both high and low urine flow rates. METHODS: Twenty-four patients ASA physical status I or II who were undergoing tympanoplasty were randomly assigned to two groups with different intravenous fluid volumes: high (10 mL kg(-1) h(-1), n = 12) and low (3 mL kg(-1) h(-1), n = 12). General anaesthesia was induced with propofol and maintained with sevoflurane (1.5-2.5%) in nitrous oxide and oxygen. Urinary bladder temperature was measured using a Foley urinary catheter; distal oesophageal temperature was measured using a stethoscope thermocouple. These temperatures were measured every 5 min during surgery and the accuracy and precision of urinary bladder temperature with oesophageal temperature were determined using regression and Bland and Altman analyses. RESULTS: The correlation coefficient for oesophageal and urinary bladder temperature was 0.90 in the high urinary volume group and 0.75 in the low urinary volume group. The offset (oesophageal-urinary bladder) was -0.13 +/- 0.32 degrees C and -0.46 +/- 0.45 degrees C, respectively. CONCLUSION: Urinary bladder temperature appears to be more accurate at high urinary flow rates than at low urinary flow rates for clinical use.


Asunto(s)
Temperatura Corporal , Esófago/fisiología , Vejiga Urinaria/fisiología , Adolescente , Adulto , Anciano , Anestesia General , Femenino , Humanos , Masculino , Persona de Mediana Edad , Timpanoplastia
9.
Clin Exp Allergy ; 38(7): 1212-9, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18498415

RESUMEN

BACKGROUND: The prevalence and severity of asthma are higher among boys than girls, but the ratios are reversed after puberty. These observations strongly suggest that sex hormones have a role in the pathogenesis of the disease. However, the mechanisms underlying the gender differences in asthma are not fully understood. OBJECTIVE: The aim of this study was to investigate sex differences in allergic inflammation in terms of immune function. METHODS: Male and female C57BL/6 mice were sensitized and challenged with ovalbumin (OVA). OVA-specific IgE in serum and airway inflammation were compared between sexes. Splenocytes from OVA-sensitized male or female donor mice were transferred to male or female naïve recipient mice. Subsequently, the recipient mice were challenged, followed by the evaluation of OVA-specific IgE and airway inflammation. Cytokines secreted from splenocytes of the sensitized mice were measured. RESULTS: The levels of OVA-specific IgE and the allergen-induced airway inflammation were higher in female than in the male mice. The contents of T-helper type 2 (Th2) cytokines, IL-4, IL-5 and IL-13, in the bronchoalveolar lavage fluid from female mice were higher than those from male mice. The airway inflammation in female recipients transferred with splenocytes from female donors was more severe than that in any other combination of recipients and donors. Splenocytes from the sensitized female mice produced more of the Th2 cytokine, IL-5, than those from the sensitized male mice upon stimulation with OVA. CONCLUSION: Our findings suggest that the sex difference in allergic airway inflammation may be attributable to the sex difference in not only the hormonal environment but also in the immune cells themselves.


Asunto(s)
Asma/inmunología , Líquido del Lavado Bronquioalveolar/inmunología , Inmunoglobulina E/sangre , Ovalbúmina/inmunología , Caracteres Sexuales , Animales , Asma/metabolismo , Líquido del Lavado Bronquioalveolar/citología , Eosinófilos/inmunología , Eosinófilos/metabolismo , Femenino , Inflamación/inmunología , Inflamación/metabolismo , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-13/biosíntesis , Interleucina-13/inmunología , Interleucina-4/biosíntesis , Interleucina-4/inmunología , Interleucina-5/biosíntesis , Interleucina-5/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL
10.
Eur J Anaesthesiol ; 25(6): 450-3, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18339218

RESUMEN

BACKGROUND AND OBJECTIVE: The inhibition of thermoregulatory control by anaesthesia is manifested by reduced vasoconstriction and shivering thresholds. As intraoperative bleeding can result in haemodynamic changes, including vasoconstriction, we investigated the effect of experimental bleeding on the shivering threshold in rabbits. METHODS: Twenty-four rabbits were randomly assigned to one of three treatment strategies: (1) no blood removal (control), (2) 5 mL kg(-1) isovolaemic blood removal and (3) 10 mL kg(-1) isovolaemic blood removal. After tracheal intubation under isoflurane anaesthesia, anaesthesia was maintained with 50% nitrous oxide in oxygen. The removed blood volume was replaced with the same volume of warm hydroxyethyl starch colloid solution. Oesophageal temperature was measured as a core temperature at 1-min intervals. After blood removal, the animal's body was cooled at a rate of 2-3 degrees C h(-1) by perfusing water at 10 degrees C through a U-shaped thermode positioned in the colon. Hypothermic shivering was evaluated by visual inspection, and the core temperature at which shivering was triggered was identified as the thermoregulatory threshold for this response. RESULTS: Just before the cooling, the body temperature of the animals was around 38.6 degrees C in all of the three groups. The shivering threshold in the control group was 37.2 +/- 0.2 degrees C (mean +/- SD). The shivering thresholds in the 5 mL kg(-1) (36.9 degrees +/- 0.3 degrees C) and 10 mL kg(-1) (36.5 degrees +/- 0.5 degrees C) blood removal groups were significantly lower and in proportion with the volume of blood removed than that in the control group. CONCLUSION: Isovolaemic haemodilution decreased the shivering threshold in rabbits in proportion with the volume of blood removed.


Asunto(s)
Anestesia/efectos adversos , Temperatura Corporal/fisiología , Hemodilución/efectos adversos , Hemodilución/métodos , Tiritona/efectos de los fármacos , Animales , Volumen Sanguíneo/fisiología , Masculino , Conejos , Distribución Aleatoria
11.
Inhal Toxicol ; 19 Suppl 1: 55-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17886051

RESUMEN

In order to investigate whether or not airborne nanoparticles with a minimum agglomeration could be used for exposure tests on animals, we developed a nanoparticle generation system and examined the biological effects of the particles in an inhalation study. The generation system was composed of an ultrasonic nebulizer and diffusion dryers, and 30 Wistar male rats were exposed to nickel oxide (NiO) nanoparticles for 4 wk (6 h/day). The geometric mean diameter of the particles and the daily average exposure concentration determined by a combination of a differential mobility analyzer and a condensation nucleus counter in the exposure chamber were 139 +/- 12 nm and 1.0 +/- 0.5 x 10(5) particles/cm3, respectively. At 4 days and 1 and 3 mo after the inhalation, each group of 10 rats were sacrificed and NiO nanoparticles deposited in the lung were determined by chemical analysis and the biopersistence (biological half time) was calculated. The deposited amount of NiO nanoparticles in the rat lungs at 4 days after the inhalation was 29 +/- 4 microg. The retained particle amount in the rat lungs after the inhalation exponentially decreased and the calculated biological half time was 62 days. The histopathological change was not severe just after the inhalation nor throughout the observation time. We concluded that nanoparticles with a minimum agglomeration were dispersed stably in the chamber and exposed to rats for 4 wk and that deposited amounts in the rat lungs and the biopersistence of the particles and the biological response in lung were detected.


Asunto(s)
Exposición por Inhalación , Pulmón/metabolismo , Nanopartículas , Níquel/farmacocinética , Animales , Cámaras de Exposición Atmosférica , Pulmón/efectos de los fármacos , Masculino , Nanopartículas/administración & dosificación , Nebulizadores y Vaporizadores , Níquel/administración & dosificación , Tamaño de la Partícula , Ratas , Ratas Wistar , Distribución Tisular/efectos de los fármacos , Distribución Tisular/fisiología
12.
Clin Exp Allergy ; 37(11): 1720-7, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17877756

RESUMEN

BACKGROUND: There has been increasing evidence suggesting the involvement of angiotensin II (Ang II) and type 1 Ang II receptors (AT1) in the pathogenesis of bronchial asthma. However, whether such an involvement would promote or suppress the pathophysiology of asthma is controversial. OBJECTIVE: The aim of this study was to investigate the role of AT1 in the development of allergic airway inflammation. METHODS: Agtr1a+/+ [wild-type C57BL/6 mice (WT)] and Agtr1a-/- mice [AT1a knockout mice (AT1aKO)] with a genetic background of C57BL/6 were systemically sensitized to ovalbumin (OVA), followed by OVA inhalation. OVA-specific IgE in serum obtained just before the inhalation was measured. Bronchoalveolar lavage (BAL) fluid and lung tissues were obtained at various time-points. Cell numbers and differentiation, and cytokine contents in BAL fluids were determined. Peribronchial accumulation of eosinophils and mucus inclusions in the bronchial epithelium were evaluated in lung tissues stained histochemically. Cell numbers and differentiation in BAL fluids of the mice were also determined after lipopolysaccharide (LPS) inhalation. RESULTS: The levels of OVA-specific IgE in AT1aKO were significantly higher than those in WT. The numbers of total cell, eosinophils and lymphocytes in BAL fluids 7 days after OVA inhalation in AT1aKO were significantly higher than those in WT. Airway inflammation in bronchial tissues in terms of eosinophil accumulation and mucus hypersecretion in AT1aKO was also stronger than in WT. The contents of IL-4, IL-5 and IL-13, but not IFN-gamma, in BAL fluids of AT1aKO were significantly higher than those of WT. In contrast, neutrophil accumulation in BAL fluids after LPS inhalation was significantly higher in WT than in AT1aKO. CONCLUSION: AT1a might be involved in the negative regulation of the development of allergic airway inflammation through polarizing the T-helper (Th) balance towards Th1 predominance. Therefore, it would be of clinical importance to investigate the effects of long-term administration of AT1 blockers on the Th1/Th2 balance in hypertensive patients with bronchial asthma.


Asunto(s)
Asma/inmunología , Bronquitis/inmunología , Receptor de Angiotensina Tipo 1/genética , Animales , Asma/inducido químicamente , Asma/fisiopatología , Bronquitis/fisiopatología , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/inmunología , Recuento de Células , Diferenciación Celular/efectos de los fármacos , Citocinas/análisis , Citocinas/metabolismo , Modelos Animales de Enfermedad , Inmunoglobulina E/sangre , Lipopolisacáridos/farmacología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Linfocitos/patología , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Moco/metabolismo , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Neutrófilos/patología , Ovalbúmina/administración & dosificación , Ovalbúmina/inmunología , Receptor de Angiotensina Tipo 1/deficiencia , Receptor de Angiotensina Tipo 1/fisiología
13.
Inflammopharmacology ; 15(2): 90-4, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17450449

RESUMEN

We investigated the effect of ecabet sodium (ecabet) on rat acute esophageal lesions induced by reflux of gastric juice. Ligation of both pylorus and fore-stomach induced the reflux of gastric juice, decreased the amount of mucus and formed hemorrhagic lesions in the esophageal mucosa. Intragastric injection of ecabet reduced the pepsin activity and prevented both the decrease of mucus amount and formation of lesions. Ecabet enhanced the reduction in lesion formation induced by omeprazole and ranitidine without a change in decreased acid concentration and pepsin activity. Digestion of mucosa and the reduction in mucus were prevented by ecabet in the everted HCl and pepsin treated esophageal sac. These results indicate that ecabet prevents esophageal lesions by inhibiting pepsin activity as well as by protecting mucus from degradation. These further implicate the therapeutic potential of ecabet for prevention/treatment of GERD, especially in combination with a proton pump inhibitor or H(2)-antagonist.


Asunto(s)
Abietanos/farmacología , Antiulcerosos/farmacología , Enfermedades del Esófago/prevención & control , Esófago/efectos de los fármacos , Jugo Gástrico/efectos de los fármacos , Abietanos/administración & dosificación , Animales , Antiulcerosos/administración & dosificación , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Quimioterapia Combinada , Enfermedades del Esófago/etiología , Esófago/patología , Reflujo Gastroesofágico/complicaciones , Masculino , Membrana Mucosa/efectos de los fármacos , Membrana Mucosa/patología , Omeprazol/farmacología , Pepsina A/efectos de los fármacos , Pepsina A/metabolismo , Ranitidina/farmacología , Ratas , Ratas Sprague-Dawley
14.
Eur J Clin Pharmacol ; 62(11): 939-46, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16953457

RESUMEN

OBJECTIVE: To examine the inhibitory effect of finasteride 1 mg on the metabolism of omeprazole in genetically determined extensive (EMs) and poor metabolizers (PMs) for CYP2C19 in young healthy Japanese male subjects. METHODS: Twenty-four volunteers participated in this study, among whom 12 were homozygous EMs and 12 were PMs for CYP2C19. A single center, controlled, randomized, open, crossover study with a 5 day washout between the two study periods was performed. Each of the six EMs and PMs received a single oral 20 mg dose of omeprazole on day 1 (treatment I). After a 5 day washout period, these subjects received 1 mg of finasteride once a day for three consecutive days, and a single oral 20 mg dose of omeprazole was co-administered on day 3 (treatment II). The 12 other EMs and PMs received treatments I and II in reverse. Plasma samples were collected for up to a 12 hours postdose of omeprazole, and the pharmacokinetic parameters of omeprazole were determined. RESULTS: The geometric mean ratio (GMR) for the AUC((0-12 hr)) of omeprazole when co-administered with finasteride/omeprazole alone is 1.13 (90%CI, 1.03, 1.25) and 0.96 (0.88, 1.05) in EMs and PMs, respectively. Finasteride did not significantly alter C(max), T(max) and t(1/2) in both genotypes. CONCLUSION: Finasteride 1 mg, widely used for the treatment of androgenetic alopecia in men, did not meaningfully increase omeprazole exposure (20 mg) in both EMs and PMs for CYP2C19. These results indicate that finasteride does not meaningfully inhibit CYP2C19 activity in vivo at the dose of 1 mg.


Asunto(s)
Antiulcerosos/farmacocinética , Hidrocarburo de Aril Hidroxilasas/genética , Pueblo Asiatico , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/farmacocinética , Finasterida/farmacología , Oxigenasas de Función Mixta/genética , Omeprazol/farmacocinética , Adulto , Antiulcerosos/metabolismo , Área Bajo la Curva , Estudios Cruzados , Citocromo P-450 CYP2C19 , Inhibidores Enzimáticos/administración & dosificación , Femenino , Finasterida/administración & dosificación , Genotipo , Humanos , Técnicas In Vitro , Masculino , Microsomas Hepáticos/metabolismo , Omeprazol/metabolismo , Farmacogenética
15.
Transplant Proc ; 37(4): 1725-7, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15919445

RESUMEN

The target blood concentrations of tacrolimus (TAC) and cyclosporine (CYA) during continuous intravenous infusion (C(ss)) have been determined based on clinical experience. However, it is desirable that C(ss) should be set so that the AUC after intravenous infusion is equal to the AUC after oral administration (AUC(po)). Accordingly, we performed 12-hour monitoring of blood concentrations to calculate C(ss) from the blood trough levels (C(TL)) on 15 kidney recipients administered TAC and 12 recipients administered CYA (Neoral). We used an area under the trough level (AUTL) as a new pharmacokinetic parameter. The C(ss) was evaluated from C(TL), AUC(po), and AUTL was calculated to be C(ss) = C(TL) x (AUC(po)/AUTL). In addition, AUTL/AUC(po) ratio and blood peak/trough level ratio (C(max)/C(min)) were examined to compare pharmacokinetics of TAC and CYA. The formula for TAC was C(ss) = C(TL) x 1.40 and that for CYA, C(ss) = C(TL) x 2.55. The calculated target C(ss) of TAC was 1.40 times that of C(TL), which was similar to the present clinical C(TL). In contrast, the calculated target C(ss) of CYA was 2.55 times the C(TL), and therefore an extremely high C(ss) was necessary to obtain a sufficient AUC that will be available after oral administration. Consequently, intravenous administration of CYA twice a day was considered to be more appropriate to obtain sufficient CYA pharmacokinetics, rather than a continuous intravenous administration. We conclude that the formula, C(ss) = C(TL) x (AUC(po)/AUTL) was useful to calculate the target blood concentration of calcineurin inhibitors when changing from continuous intravenous infusion to oral administration of these drugs.


Asunto(s)
Ciclosporina/sangre , Inmunosupresores/sangre , Trasplante de Riñón/fisiología , Tacrolimus/sangre , Administración Oral , Área Bajo la Curva , Ciclosporina/administración & dosificación , Ciclosporina/uso terapéutico , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/uso terapéutico , Infusiones Intravenosas , Trasplante de Riñón/inmunología , Tacrolimus/administración & dosificación , Tacrolimus/uso terapéutico
16.
Transplant Proc ; 37(4): 1739-40, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15919450

RESUMEN

We performed 24-hour monitoring of cyclosporine (NEO) and tacrolimus (TAC) blood concentrations, evaluating pharmacokinetic parameters and characterizing circadian variations. The monitoring was performed in 10 instances on nine patients administered NEO and 12 out of 11 patients administered TAC. All cases were administered equally divided doses of drugs twice daily orally. Blood samples were taken before and 1, 2, 3, 4, 6, and 12 hours after NEO or TAC administration in the morning and evening. The pharmacokinetic parameters were compared between morning and evening administrations of both drugs. AUC0-12, AUC0-4, C(max), C2, and C(max)/C(min) of NEO and TAC were significantly lower during the evening compared with morning administrations. C(min) values were significantly higher in the evening. T(max) of NEO was longer in evening, although there was not a significant difference; T(max) of TAC was significantly longer in the evening. We found that NEO and TAC administrations in the evening resulted in reduced bioavailability and delayed absorption when compared with drug administrations in the morning. It was thought that the difference in bioavailability between morning and evening administrations was smaller with TAC, because TAC shows lower peak levels and a flatter blood concentration curve than NEO. C(min) was higher after evening administration than morning because of delayed absorption, though the bioavailability of both drugs decreased in the evening. These results suggest that we have to appreciate apparently high trough levels.


Asunto(s)
Ciclosporina/farmacocinética , Tacrolimus/farmacocinética , Administración Oral , Área Bajo la Curva , Ritmo Circadiano , Ciclosporina/administración & dosificación , Ciclosporina/uso terapéutico , Esquema de Medicación , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/farmacocinética , Inmunosupresores/uso terapéutico , Tacrolimus/administración & dosificación , Tacrolimus/uso terapéutico
17.
Transplant Proc ; 37(4): 1745-7, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15919452

RESUMEN

We evaluated the relative clinical potency of cyclosporine (CyA) and tacrolimus (Tac) using pharmacodynamic and pharmacokinetic parameters of the drug to obtain the most suitable converting dose and target trough level. The relative pharmacodynamic potency was examined by the mean ratio of drug concentrations giving 50% inhibition of blastogenesis of lymphocytes (IC50) in 66 chronic renal failure patients. The relative potency estimated from clinical pharmacokinetic parameters was examined by the mean ratio of each pharmacokinetic parameter value of CyA versus Tac. The pharmacokinetic parameters were estimated by 12-hour monitoring of drug blood concentrations in seven CyA patients and seven Tac patients. The mean IC50 ratio of CyA and Tac (CyA/Tac of IC50) was 25.1. The mean area under the concentration-time curve (AUC) ratio (CyA/Tac of AUC) was 25.5, the mean trough level (C(min)) ratio (CyA/Tac of C(min)) was 13.2, and the mean dose per body weight ratio was 25.2. The relative potency estimated from AUC that is the most reliable pharmacokinetic parameter for the estimation of clinical efficacy of calcineurin inhibitors appeared to agree with the relative pharmacodynamic potency estimated from IC50. The data suggest that TAC 25-fold more potent than CyA, which represents a suitable converting dose ratio, and that target trough level of CyA is about 13-fold greater than Tac based on CyA/Tac of C(min). We conclude that these relative values may be useful to estimate the suitable dose and target trough levels to convert between CyA and Tac.


Asunto(s)
Ciclosporina/farmacocinética , Ciclosporina/uso terapéutico , Trasplante de Riñón/inmunología , Linfocitos/inmunología , Tacrolimus/farmacocinética , Tacrolimus/uso terapéutico , Área Bajo la Curva , Ciclosporina/sangre , Humanos , Inmunosupresores/sangre , Inmunosupresores/farmacocinética , Inmunosupresores/uso terapéutico , Linfocitos/efectos de los fármacos , Tacrolimus/sangre
18.
Calcif Tissue Int ; 74(6): 509-15, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15354858

RESUMEN

We investigated the relationships between tumor necrosis factor (TNF) gene polymorphism, circulating TNF-alpha (TNF-alpha) concentrations, and bone mineral density (BMD) in the lumbar spine. TNF gene polymorphisms studied were the Nco I polymorphism within the first intron of TNF-beta (TNF-beta) and three single nucleotide polymorphisms in the promoter region of the TNF-alpha gene, at positions -857, -863, and -1031. Allelic variants of the TNF gene were identified using restriction fragment length polymorphism (RFLP) analysis in 177 postmenopausal Japanese women within 10 years after menopause, aged 56.4 +/- 4.5 years (mean +/- SD). A significantly higher prevalence of the alleles TNF-alpha-863A (20.3% versus 9.9%) and TNF-alpha-1031C (21.3% versus 12.4%) was seen in the low BMD group (Z-score < 0, n = 91) than in the high BMD group (0 < Z-score, n = 86). In genotype analysis, although difference did not reach a significant level, women with the rarest allelic variants, i.e., homozygous TNFbl, TNF-alpha-863A, and TNF-alpha-1031C, showed the lowest BMD Z-scores. Women with another rarest allelic variant, TNF-alpha-857T/T had significantly lower BMD Z-scores than did women with TNF-alpha-857C/T or -857C/C. The BMD Z-score decreased significantly with an increase in the total number of such rare alleles. Serum concentrations of TNF-alpha did not differ significantly among groups divided by genotypes. Multiple linear regression analysis revealed that the total number of rare alleles, in addition to the body mass index and the number of years since menopause, was an independent predictor of the BMD. These presumptive functional polymorphisms of the TNF gene may be associated with the lumbar spine BMD in early postmenopausal Japanese women.


Asunto(s)
Pueblo Asiatico , Densidad Ósea/genética , Vértebras Lumbares/metabolismo , Polimorfismo de Nucleótido Simple , Posmenopausia , Factor de Necrosis Tumoral alfa/genética , Absorciometría de Fotón , Cartilla de ADN/química , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Japón/epidemiología , Desequilibrio de Ligamiento , Linfotoxina-alfa/genética , Persona de Mediana Edad , Osteoporosis Posmenopáusica/epidemiología , Osteoporosis Posmenopáusica/genética , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Factor de Necrosis Tumoral alfa/metabolismo
19.
Br J Anaesth ; 90(1): 88-90, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12488386

RESUMEN

BACKGROUND: Comparable minimum alveolar concentration (MAC) fractions of volatile anaesthetics produce similar thermoregulatory impairment. Nitrous oxide, however, decreases the vasoconstriction threshold less than sevoflurane or isoflurane. We tested the hypothesis that nitrous oxide also decreases shivering threshold less than isoflurane alone or in combination. METHODS: Twenty-four rabbits were assigned randomly to one of three 0.3 MAC anaesthetic regimens: (i) nitrous oxide 69%; (ii) nitrous oxide 35% and isoflurane 0.3%; or (iii) isoflurane 0.6%. Body temperature was lowered by perfusing 10 degrees C water through a U-shaped thermode positioned in the colon. Shivering was evaluated by inspection. RESULTS: The rabbits anaesthetized with nitrous oxide alone shivered at 37.0 (0.5) degrees C (P<0.01 vs other groups). In those given the nitrous oxide and isoflurane combination, the shivering threshold was 36.4 (0.5) degrees C and that in the isoflurane group was 35.9 (0.4) degrees C. CONCLUSION: This study indicates that nitrous oxide reduces the shivering threshold less than isoflurane.


Asunto(s)
Anestésicos por Inhalación/farmacología , Isoflurano/farmacología , Óxido Nitroso/farmacología , Tiritona/efectos de los fármacos , Animales , Regulación de la Temperatura Corporal/efectos de los fármacos , Masculino , Conejos , Tiritona/fisiología
20.
Nihon Arukoru Yakubutsu Igakkai Zasshi ; 36(5): 504-13, 2001 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-11725535

RESUMEN

To clarify the influence of chronic and excessive alcohol consumption on gustatory function, we examined taste functions of 20 male alcoholics by total oral gustometry using salty, sweet, sour, bitter and glutamate solutions. As results, all patients showed markedly impaired taste in all kinds of solutions comparing with age and sex matched healthy persons, nevertheless none of them recognized their impaired taste. Serum zinc levels of all patients were within reference range, but the most of them were within lower part of reference level. Although average serum zinc level increased significantly after 5 weeks of admission, serum zinc level showed no significant correlation with taste function. From these findings, we concluded that alcoholics had impaired taste functions probably due to impaired peripheral nervous system.


Asunto(s)
Alcoholismo/complicaciones , Enfermedades del Nervio Glosofaríngeo/etiología , Adulto , Enfermedades del Nervio Glosofaríngeo/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso Periférico/etiología , Zinc/deficiencia
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