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1.
Skin Res Technol ; 24(1): 93-98, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28868761

RESUMO

BACKGROUND: Sagging skin is one of the most concerning esthetic issues for elderly individuals. Although reduced skin elasticity has been reported as the cause of sagging skin, a loss of skin elasticity alone is insufficient to explain sagging facial skin. This study investigated the mechanisms underlying sagging skin, with a focus on the subcutaneous network of collagenous fibers known as the retinacula cutis (RC). METHODS: To evaluate the structure of the RC noninvasively, tomographic images of the face were obtained using magnetic resonance imaging (MRI). The RC was identified by comparing MRI results with histological specimens of human skin. A descriptive scale was used to evaluate the degree of sagging, and a device equipped with a 6-mm-diameter probe was used to measure the elasticity of deeper skin layers and evaluate the physical properties of the skin. RESULTS: The density of RC in subcutaneous tissue correlated negatively with sagging scores and positively with elasticity. CONCLUSION: These results imply that a sparse RC structure contributes to a reduction in the elasticity of subcutaneous tissue, resulting in a greater degree of sagging facial skin. These findings are expected to contribute to the understanding of the mechanisms underlying sagging skin.


Assuntos
Face/patologia , Envelhecimento da Pele/patologia , Tela Subcutânea/patologia , Adulto , Envelhecimento/patologia , Envelhecimento/fisiologia , Bochecha/diagnóstico por imagem , Bochecha/patologia , Colágeno/análise , Elasticidade , Face/diagnóstico por imagem , Face/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Pele/química , Pele/diagnóstico por imagem , Pele/patologia , Envelhecimento da Pele/fisiologia , Fenômenos Fisiológicos da Pele , Tela Subcutânea/diagnóstico por imagem , Adulto Jovem
2.
Haemophilia ; 18(3): e323-30, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22044430

RESUMO

Haemophilia A is a life long bleeding disorder caused by an inherited deficiency of factor VIII (FVIII). About 30% of haemophilia A patients develop neutralizing antibodies as a consequence of treatment with FVIII concentrates. Immune tolerance protocols for the eradication of inhibitors require daily delivery of intravenous FVIII. We evaluated the immune responses to serial intravenous administration of FVIII in preimmunized haemophilia A mice. We introduced an implantable venous-access device (iVAD) system into haemophilia A mice to facilitate sequential infusion of FVIII. After preimmunization with FVIII, the haemophilia A mice were subjected to serial intravenous administration of FVIII through the iVAD system. In all mice with serial infusion of FVIII, high titers of anti-FVIII inhibitory antibodies developed at 10 exposure days (EDs). However, the anti-FVIII IgG titers were decreased after 150 EDs of sequential low-dose infusion of FVIII [0.05 U g(-1) body weight (BW) five times per week]. Proliferative response to ex vivo FVIII stimulation was significantly suppressed in splenic CD4(+) T cells from mice with serial low-dose FVIII infusion compared with those from mice with high-dose FVIII infusion (0.5 U g(-1) BW five times per week) or preimmunized mice. Moreover, splenic CD4(+) T cells from mice with serial low-dose infusion of FVIII failed to produce interleukin-2 and interferon-γ. These data suggest that serial infusion of FVIII could induce T-cell anergy in haemophilia A mice with inhibitor antibodies.


Assuntos
Inibidores dos Fatores de Coagulação Sanguínea/imunologia , Coagulantes/imunologia , Fator VIII/imunologia , Hemofilia A/imunologia , Tolerância Imunológica/efeitos dos fármacos , Animais , Inibidores dos Fatores de Coagulação Sanguínea/sangue , Cateterismo Venoso Central , Cateteres de Demora , Proliferação de Células/efeitos dos fármacos , Coagulantes/administração & dosagem , Citocinas/metabolismo , Modelos Animais de Doenças , Fator VIII/administração & dosagem , Hemofilia A/tratamento farmacológico , Hemofilia A/metabolismo , Imunoglobulina G/sangue , Infusões Intravenosas , Isoanticorpos/sangue , Camundongos
3.
AJNR Am J Neuroradiol ; 42(6): 1038-1045, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33737266

RESUMO

BACKGROUND AND PURPOSE: Cerebral amyloid angiopathy (CAA) is a known risk factor for ischemic stroke though angiographic imaging is often negative. Our goal was to determine the relationship between vessel wall enhancement (VWE) in acute and future ischemic stroke in CAA patients. MATERIALS AND METHODS: This was a retrospective study of patients with new-onset neurologic symptoms undergoing 3T vessel wall MR imaging from 2015 to 2019. Vessel wall enhancement was detected on pre- and postcontrast flow-suppressed 3D T1WI. Interrater agreement was evaluated in cerebral amyloid angiopathy-positive and age-matched negative participants using a prevalence- and bias-adjusted kappa analysis. In patients with cerebral amyloid angiopathy, multivariable Poisson and Cox regression were used to determine the association of vessel wall enhancement with acute and future ischemic stroke, respectively, using backward elimination of confounders to P < .20. RESULTS: Fifty patients with cerebral amyloid angiopathy underwent vessel wall MR imaging, including 35/50 (70.0%) with ischemic stroke and 29/50 (58.0%) with vessel wall enhancement. Prevalence- and bias-corrected kappa was 0.82 (95% CI, 0.71-0.93). The final regression model for acute ischemic stroke included vessel wall enhancement (prevalence ratio = 1.5; 95% CI, 1.1-2.2; P = .022), age (prevalence ratio = 1.02; 95% CI, 1.0-1.05; P = .036), time between symptoms and MR imaging (prevalence ratio = 0.9; 95% CI, 0.8-0.9; P < .001), and smoking (prevalence ratio = 0.7; 95% CI, 0.5-1.0; P = .042) with c-statistic = 0.92 (95% CI, 0.84-0.99). Future ischemic stroke incidence with cerebral amyloid angiopathy was 49.7% (95% CI, 34.5%-67.2%) per year over a total time at risk of 37.5 person-years. Vessel wall enhancement-positive patients with cerebral amyloid angiopathy demonstrated significantly shorter stroke-free survival with 63.9% (95% CI, 43.2%-84.0%) versus 32.2% (95% CI, 14.4%-62.3%) ischemic strokes per year, chi-square = 4.9, P = .027. The final model for future ischemic stroke had a c-statistic of 0.70 and included initial ischemic stroke (hazard ratio = 3.4; 95% CI, 1.0-12.0; P = .053) and vessel wall enhancement (hazard ratio = 2.5; 95% CI, 0.9-7.0; P = .080). CONCLUSIONS: Vessel wall enhancement is associated with both acute and future stroke in patients with cerebral amyloid angiopathy.


Assuntos
Angiopatia Amiloide Cerebral , Acidente Vascular Cerebral , Idoso , Isquemia Encefálica , Angiopatia Amiloide Cerebral/complicações , Angiopatia Amiloide Cerebral/diagnóstico por imagem , Hemorragia Cerebral , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia
4.
J Exp Med ; 176(3): 887-91, 1992 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-1387415

RESUMO

The identity of the guanine nucleotide-binding protein (G protein) involved in T cell activation pathways remains unclear. We identified a 68-kD GTP-binding protein associated with the T cell receptor (TCR)/CD3 complex using immunoprecipitation and GTP-affinity labeling techniques. Proteins coimmunoprecipitated with the TCR/CD3 complex in digitonin lysate of a human leukemic T cell line, MOLT 16, were incubated with alpha-[32P]GTP and irradiated with ultraviolet rays to covalently link the labeled GTP to GTP-binding proteins. They were then analyzed by electrophoresis. The 68-kD protein exhibited nucleotide specificity for GTP-binding and was insensitive to cholera and pertussis toxins. The 68-kD GTP-binding protein could be coimmunoprecipitated with the TCR/CD3 complex but not with other surface molecules such as major histocompatibility complex class I and lymphocyte function associated-1, which do not cause rapid Ca2+ mobilization. These suggest that the 68-kD GTP-binding protein is specifically associated with the TCR/CD3 complex.


Assuntos
Antígenos de Diferenciação de Linfócitos T/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/metabolismo , Antígenos de Diferenciação de Linfócitos T/imunologia , Complexo CD3 , Eletroforese em Gel de Poliacrilamida , Humanos , Ativação Linfocitária , Testes de Precipitina , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia
5.
Cephalalgia ; 29(12): 1259-66, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19911463

RESUMO

To clarify if migraine-associated vertigo (MAV) and Meniere's disease (MD) share a common pathophysiology, vestibular-evoked myogenic potentials (VEMP) were measured in 11 patients with MAV, 11 with unilateral MD and eight healthy subjects. As acoustic stimuli, tone bursts (TB; 250, 500, 1000 and 2000 Hz) were presented. In healthy subjects, 500-Hz TB evoked the largest amplitude. To quantify this tendency, 500-1000 VEMP slope was calculated, and 500-1000 VEMP slope was the smallest on the affected side of MD patients. Among the 11 MD patients, five had significantly decreased 500-1000 VEMP asymmetry (shift of the tuning to 1000 Hz). Three of the 11 MAV patients also showed a significantly decreased 500-1000 VEMP slope. This finding suggests that MAV might share a common pathophysiology with MD. In addition to this finding, four of the other eight MAV patients showed prolonged p13 latencies. This suggests that MAV could consist of patients with different lesion sites.


Assuntos
Potenciais Evocados Auditivos/fisiologia , Doença de Meniere/fisiopatologia , Enxaqueca com Aura/fisiopatologia , Sáculo e Utrículo/fisiologia , Vertigem/fisiopatologia , Estimulação Acústica , Adulto , Hidropisia Endolinfática/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Tempo de Reação/fisiologia , Sáculo e Utrículo/inervação
6.
AJNR Am J Neuroradiol ; 39(2): 265-272, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29301781

RESUMO

BACKGROUND AND PURPOSE: Amide proton transfer imaging has been successfully applied to brain tumors, however, the relationships between amide proton transfer and other quantitative imaging values have yet to be investigated. The aim was to examine the additive value of amide proton transfer imaging alongside [18F] FDG-PET and DWI for preoperative grading of gliomas. MATERIALS AND METHODS: Forty-nine patients with newly diagnosed gliomas were included in this retrospective study. All patients had undergone MR imaging, including DWI and amide proton transfer imaging on 3T scanners, and [18F] FDG-PET. Logistic regression analyses were conducted to examine the relationship between each imaging parameter and the presence of high-grade (grade III and/or IV) glioma. These parameters included the tumor-to-normal ratio of FDG uptake, minimum ADC, mean amide proton transfer value, and their combinations. In each model, the overall discriminative power for the detection of high-grade glioma was assessed with receiver operating characteristic curve analysis. Additive information from minimum ADC and mean amide proton transfer was also evaluated by continuous net reclassification improvement. P < .05 was considered significant. RESULTS: Tumor-to-normal ratio, minimum ADC, and mean amide proton transfer demonstrated comparable diagnostic accuracy in differentiating high-grade from low-grade gliomas. When mean amide proton transfer was combined with the tumor-to-normal ratio, the continuous net reclassification improvement was 0.64 (95% CI, 0.036-1.24; P = .04) for diagnosing high-grade glioma and 0.95 (95% CI, 0.39-1.52; P = .001) for diagnosing glioblastoma. When minimum ADC was combined with the tumor-to-normal ratio, the continuous net reclassification improvement was 0.43 (95% CI, -0.17-1.04; P = .16) for diagnosing high-grade glioma, and 1.36 (95% CI, 0.79-1.92; P < .001) for diagnosing glioblastoma. CONCLUSIONS: Addition of amide proton transfer imaging to FDG-PET/CT may improve the ability to differentiate high-grade from low-grade gliomas.


Assuntos
Glioma/diagnóstico por imagem , Gradação de Tumores/métodos , Neuroimagem/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto , Idoso , Neoplasias Encefálicas/patologia , Feminino , Fluordesoxiglucose F18 , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
Bone Marrow Transplant ; 37(6): 601-5, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16444280

RESUMO

Eight children underwent reduced-intensity stem cell transplantation (RIST) from an HLA-matched sibling. They received a fludarabine-melphalan based preparative regimen. Stem cell source was bone marrow, and GVHD prophylaxis consisted of cyclosporine A alone. Acute GVHD grade II-IV and grade III-IV were observed in four (50%) and three (37.5%), respectively, out of these eight patients. This incidence was significantly higher than that after conventional bone marrow transplantation, without severe tissue damage, in the same setting of stem cell source and GVHD prophylaxis. Although the number of patients is small, our results suggest that incidence of acute GVHD after RIST for children is significant. It should be remembered that RIST for children does not seem to be an easy transplant procedure from the viewpoint of acute GVHD, although RIST is less toxic.


Assuntos
Transplante de Medula Óssea/métodos , Doença Enxerto-Hospedeiro/epidemiologia , Teste de Histocompatibilidade , Leucemia/terapia , Linfoma/terapia , Neoplasias/terapia , Transplante de Células-Tronco/métodos , Adolescente , Contagem de Células , Criança , Pré-Escolar , Doença Enxerto-Hospedeiro/fisiopatologia , Humanos , Incidência , Lactente , Japão , Masculino , Estudos Retrospectivos
8.
Int J Hematol ; 82(5): 437-40, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16533748

RESUMO

Recent findings indicate that Epstein-Barr virus (EBV)-infected T-/natural killer (NK) cells play an important role in the pathogenesis of mosquito allergy, and most patients with mosquito allergy die early in life if not properly treated. Over the last 7 years, we have been using combination chemotherapy and allogeneic stem cell transplantation for the treatment of EBV-associated T-/NK cell lymphoproliferative disease (LPD) in which chronic active EBV infection and mosquito allergy were included. As of this writing, we have successfully treated 2 patients with mosquito allergy with chemotherapy in which EBV-infected T-/NK cells were eradicated. The findings suggest the possible role of chemotherapy in the treatment of EBV-associated T-/NK cell LPD.


Assuntos
Culicidae , Infecções por Vírus Epstein-Barr/terapia , Hipersensibilidade Imediata/terapia , Mordeduras e Picadas de Insetos/terapia , Células Matadoras Naturais , Transtornos Linfoproliferativos/terapia , Linfócitos T , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Criança , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/patologia , Feminino , Humanos , Hipersensibilidade Imediata/complicações , Hipersensibilidade Imediata/patologia , Mordeduras e Picadas de Insetos/complicações , Mordeduras e Picadas de Insetos/patologia , Células Matadoras Naturais/patologia , Células Matadoras Naturais/virologia , Transtornos Linfoproliferativos/complicações , Transtornos Linfoproliferativos/patologia , Masculino , Indução de Remissão/métodos , Transplante de Células-Tronco/métodos , Linfócitos T/patologia , Linfócitos T/virologia , Transplante Homólogo
9.
Leukemia ; 11(12): 2168-74, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9447837

RESUMO

A human acute lymphoblastic leukemia (ALL) cell line, BALM-16, was established from the peripheral blood specimen of a patient with B cell ALL L3 type (ALL-L3) in relapse. As with the original leukemia cells, the established line was negative for both cell surface and cytoplasmic immunoglobulin (Ig) chains. Absence of Ig expression was confirmed by Western blotting. Southern blot analysis demonstrated homozygous deletion of the C kappa gene, germ line configuration of the C lambda and rearrangement of IgJH genes. Cytogenetic analysis of both leukemic bone marrow and BALM-16 cells showed the t(8;22)(q24;q11) abnormality which is specifically associated with ALL-L3 and Burkitt lymphoma. The patient's serum showed hypercalcemia, prompting further investigation of the established cell lines which showed parathyroid hormone-related peptide (PTHrP) mRNA detected by reverse-transcriptase polymerase chain reaction. However, PTHrP production was not detected in the culture supernatant. The established cell line, BALM-16, could provide a useful material for analyzing the lack of Ig expression and of clarifying the pathogenesis of this type of B cell malignancy.


Assuntos
Hipercalcemia/imunologia , Imunoglobulinas/análise , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Adulto , Antígenos CD/análise , Southern Blotting , Aberrações Cromossômicas , Genes de Imunoglobulinas , Humanos , Masculino , Proteína Relacionada ao Hormônio Paratireóideo , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas/análise , Células Tumorais Cultivadas
10.
Rev Sci Instrum ; 86(2): 023106, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25725822

RESUMO

A spectrometer to detect the ultra-weak luminescence originated by the collision of cluster ions on the surfaces of solid materials was constructed. This spectrometer consists of 11 photomultipliers with band-pass interference filters that can detect the luminescence within the wavelength ranging from 300 to 700 nm and of a photomultiplier without filter. The calibration of the detection system was performed using the photons emitted from a strontium aluminate fluorescent tape and from a high temperature tungsten filament. Preliminary measurements show the ability of this spectrometer to detect the cluster ion beam induced luminescence.

11.
Immunol Lett ; 68(2-3): 301-9, 1999 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10424436

RESUMO

Activation of resting B cells requires an initial triggering of the B cell antigen receptor (BCR) and secondary stimuli through various cytokine receptors and B cell activation molecules including CD40. We found that activation of B cells through CD40 is selectively inhibited by an immunosuppressant drug, rapamycin. This effect of rapamycin on anti-CD40-mediated activation of B cells was observed using three different in vitro assays. Rapamycin suppressed the anti-CD40-induced proliferation of splenic B cells, suppressed differentiation to surface IgMhigh/IgDlow B cells, and inhibited an anti-CD40-mediated prevention of apoptosis induced by BCR cross-linkage of WEHI-231 cells. We next examined several known CD40 signal transduction pathways to identify the target of rapamycin in stimulated B cells. Rapamycin did not inhibit the activation of c-Jun N-terminal kinases (JNKs) induced by anti-CD40 stimulation nor the activation of immediate nuclear transcription factors of NF-kappaB. Therefore, rapamycin affects a novel element of the CD40 signal transduction pathway which influences the proliferation, differentiation, and prevention of apoptosis of B cells.


Assuntos
Linfócitos B/efeitos dos fármacos , Antígenos CD40/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno , Sirolimo/farmacologia , Androstadienos/farmacologia , Animais , Antígenos de Diferenciação de Linfócitos B , Apoptose/efeitos dos fármacos , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Interações Medicamentosas , Imunoglobulina D/isolamento & purificação , Imunoglobulina M/isolamento & purificação , Imunossupressores/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Receptores de Antígenos de Linfócitos B/isolamento & purificação , Transdução de Sinais , Baço/citologia , Baço/imunologia , Wortmanina
12.
Biochem Pharmacol ; 46(6): 1096-9, 1993 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-8105783

RESUMO

The blood-brain barrier permeability of cyclosporin A (CsA), an immunosuppressive cyclic peptide, is restricted despite its highly lipophilic nature. In this study, the uptake of CsA by primary cultured bovine brain capillary endothelial cells (BCEC) was investigated in order to clarify whether P-glycoprotein (P-gp), an ATP-dependent drug efflux pump expressed in the luminal surface of BCEC, causes the decreased transport of CsA into the brain. P-gp, having a molecular mass of 130-140 kDa, was detected with anti-P-gp monoclonal antibody, C219, using western blot analysis of the membrane fraction isolated from the bovine brain capillary. The uptake of CsA by primary cultured bovine BCEC was time-dependent, and the steady-state uptake of CsA was increased in the presence of several multidrug resistance reversing agents including verapamil and steroid hormones and the substrate of P-gp in BCEC, vincristine. The steady-stage uptake was increased significantly to approximately 4-fold when cellular ATP was depleted by treating with 2,4-dinitrophenol, suggesting that the efflux process is ATP dependent. Furthermore, in the presence of an anti-P-gp monoclonal antibody, MRK16, at a 10 micrograms/mL concentration, the uptake of CsA was increased approximately 3-fold. These results suggest that the low permeability of CsA into the brain is caused by the active efflux from BCEC by P-gp present in the luminal surface of cells.


Assuntos
Barreira Hematoencefálica/fisiologia , Proteínas de Transporte/fisiologia , Ciclosporina/metabolismo , Glicoproteínas de Membrana/fisiologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Animais , Proteínas de Transporte/análise , Bovinos , Células Cultivadas/efeitos dos fármacos , Clorpromazina/farmacologia , Ciclosporina/farmacologia , Glicoproteínas de Membrana/análise , Progesterona/farmacologia , Trítio , Verapamil/farmacologia , Vincristina/farmacologia
13.
Biochem Pharmacol ; 48(10): 1989-92, 1994 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-7986214

RESUMO

To evaluate the significance of P-glycoprotein (P-gp)-mediated active efflux on the blood-brain barrier (BBB) permeability of cyclosporin A (CsA) in vivo, we investigated the effects of ATP depletion in the brain and of a multidrug-resistant (MDR) reversing agent on the transport of CsA across the BBB. Using transient brain ischemia obtained by 4-vessel occlusion of vertebral and common carotid arteries in rats to deplete ATP content in the brain, the estimated permeability surface area product (PS) value of [3H]CsA was increased 2.7-fold compared with that in normal rats, whereas the PS value of [14C]sucrose was not altered. Additionally, when quinidine hydrochloride (QND) was infused into the brain through a microdialysis probe implanted in the rat hippocampus, the extravascular extraction of CsA was increased to approximately 2.5-fold of the control, whereas no difference in the extravascular extraction between control and normal rats having no implanted dialysis probe was observed. Furthermore, the efflux rate from brain to blood of CsA was decreased remarkably to 5% of control at steady-state by co-administration of CsA with QND directly into the brain through the dialysis probe. The ATP-dependent and QND-sensitive efflux of CsA from the brain strongly indicates that P-gp in the brain capillary endothelial cells functions as an efflux pump under the physiological state, and that P-gp-mediated efflux of CsA is a major mechanism of the restricted transfer from blood into the brain.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Trifosfato de Adenosina/metabolismo , Barreira Hematoencefálica , Ciclosporina/farmacocinética , Animais , Transporte Biológico , Masculino , Ratos , Ratos Endogâmicos F344
14.
Biochem Pharmacol ; 49(10): 1541-4, 1995 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-7763297

RESUMO

We investigated the role of ATP in the active efflux of doxorubicin (DOX) mediated by P-glycoprotein (P-gp), the multidrug-resistance (MDR) gene product, at the blood-brain barrier. In transient brain ischemic rats prepared with 4-vessel occlusion of vertebral and common carotid arteries for 20 min, a procedure that depleted their brain ATP content to 3% that of normal rats, the estimated permeability coefficient of DOX was increased 17-fold (to 243 +/- 2.5 microL/min/g brain). When the ATP content recovered to a normal level by means of 30-min and 24-hr cerebral recirculation of blood, the permeability coefficient recovered to 14.0 +/- 5.0 and 18.4 +/- 2.3 microL/min/g brain (mean +/- SEM, N = 3-6), respectively, very close to the control permeability (14.3 +/- 1.5 microL/min/g brain). The uptake of DOX by primary cultured brain capillary endothelial cells expressing P-gp at the luminal membrane was increased significantly (up to 2-fold), which correlated well with the decrease of cellular ATP contents caused by treating the cells with metabolic inhibitors. Evidence for the ATP-dependent transport of DOX obtained from the present in vivo and in vitro studies strongly indicates that P-gp in the brain capillaries functions actively as an efflux pump in the physiological state, providing a major mechanism to restrict the transfer of DOX into the brain.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Trifosfato de Adenosina/metabolismo , Barreira Hematoencefálica , Doxorrubicina/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/farmacologia , Animais , Transporte Biológico , Barreira Hematoencefálica/efeitos dos fármacos , Células Cultivadas , Endotélio Vascular/metabolismo , Ataque Isquêmico Transitório/metabolismo , Masculino , Ratos
15.
Artigo em Inglês | MEDLINE | ID: mdl-10621955

RESUMO

1. Occurrence of miniature endplate potentials (MEPP) in the sartorius muscle of Rana catesbiana in high Mg2+ Ringer solution were observed in standard intracellular recording. Intervals and amplitudes of sequentially occurring MEPP were registered and analyzed. 2. Interval histograms of a time series of MEPP showed exponential-like pattern as reported in the classical study by Fatt and Katz (1952). The cumulative distribution of the intervals plotted in logarithmic axes showed two distinct phases. In shorter intervals (< 1s), curve along exponential decay was observed, and in longer intervals (> or = 1s) linear decay can be seen. The latter power-law relation gave dimensions of 4.111 +/- 0.812 (mean and S.D.). Self-similarity in longer range implies a time-scale invariant nature and may suggest fractal nature in restoration process of synaptic vesicles, while exponential decay in the short time interval range implies random release of transmitter packet from the readily releasable pool. 3. Fluctuation of amplitudes in sequentially occurred MEPP were analyzed according to Higuchi's cumulative route-length analysis. The estimates for sequential amplitude curve showed the power-law relation in a logarithmic plot whose inclination (= D) estimated with linear regression analysis was 1.996 +/- 0.007 (mean and S.D.). This results indicate that fluctuation in the amplitude of MEPP shows possible maximum complexity as a graphic curve in 2-D plane. Similar result was obtained for fluctuation of intervals of successively occurring MEPP.


Assuntos
Placa Motora/fisiologia , Junção Neuromuscular/fisiologia , Algoritmos , Animais , Eletrofisiologia , Fractais , Técnicas In Vitro , Potenciais da Membrana/fisiologia , Placa Motora/metabolismo , Junção Neuromuscular/metabolismo , Neurotransmissores/metabolismo , Rana catesbeiana , Análise de Regressão , Nervo Isquiático/metabolismo , Nervo Isquiático/fisiologia
16.
J Chromatogr A ; 811(1-2): 69-76, 1998 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-9691301

RESUMO

Filter paper pieces-based (FPB) DEAE-celluloses was prepared for direct fractionation of proteins in particle-containing feedstocks. FPB DEAE-cellulose has a protein binding capacity equivalent to that of commercially available DEAE-cellulose. Crude extracts from porcine intestine and kiwi fruit pulp, which were unmanageable by commercially available chromatographic media due to rapid clothing, could be directly fractionated with FPB DEAE-cellulose column. In addition, effluents from an FPB DEAE-cellulose column were extensively clarified. The present approach can be used as a rapid, robust and low-cost capturing step for protein from particle-containing feedstocks.


Assuntos
Proteínas Alimentares/análise , Animais , Cromatografia DEAE-Celulose , Cromatografia em Papel , Custos e Análise de Custo , Filtração , Análise de Alimentos , Frutas/química , Carne/análise , Reprodutibilidade dos Testes , Suínos , Viscosidade
17.
J Pharm Sci ; 88(12): 1281-7, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10585223

RESUMO

To determine the contribution of the mdr1a gene product to digoxin pharmacokinetics, we constructed a physiologically based pharmacokinetic model for digoxin in mdr1a (-/-) and mdr1a (+/+) mice. After intravenous administration, total body clearance and tissue-to-plasma concentration ratios for muscle and heart were decreased in mdr1a (-/-) mice as compared with mdr1a (+/+) mice, and in particular, the digoxin concentration in the brain was 68-fold higher than that in mdr1a (+/+) mice at 12 h. On the other hand, mdr1a gene disruption did not change the contributions of renal and bile clearances to total clearance, the plasma protein binding, or the blood-to-plasma partition coefficient. Brain concentration-time profiles in mdr1a (+/+) and mdr1a (-/-) mice showed a different pattern from those in plasma and other tissues, indicating digoxin accumulation in the brain tissue. Because there was no difference in the uptake or release of digoxin by brain tissue slices from the two types of mice, we assumed the brain tissue compartment to consist of two parts (a well-stirred part with influx and efflux clearance and an accumulative part). Simulation with this model gave excellent agreement with observation when active efflux clearance across the blood-brain barrier was assumed to be zero in mdr1a (-/-) mice. The observations in other tissues in both types of mice were also well simulated.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/genética , Cardiotônicos/farmacocinética , Digoxina/farmacocinética , Genes MDR/genética , Algoritmos , Animais , Bile/metabolismo , Proteínas Sanguíneas/metabolismo , Encéfalo/metabolismo , Cardiotônicos/sangue , Cardiotônicos/urina , Digoxina/sangue , Digoxina/urina , Técnicas In Vitro , Injeções Intravenosas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Esquelético/metabolismo , Ligação Proteica , Distribuição Tecidual
18.
Pharmacol Biochem Behav ; 69(3-4): 383-90, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11509195

RESUMO

Various plant-derived essential oils (EOs) have traditionally been used in the treatment of mental disorders, despite a lack of scientific evidence. In a previous study, we demonstrated that certain EOs possess behavioral effects, a finding that supports our original hypotheses that EOs possess psychoactive actions. The present study was conducted in order to obtain further evidence to support our hypothesis. Peppermint oil, a type of EO, is believed to be effective for treating mental fatigue. When the oil was administered intraperitoneally to ICR mice, the ambulatory activity of mice increased dramatically. We identified alpha-pinene, beta-pinene, (R)-(+)-limonene, 1,8-cineol, isomenthone, menthone, menthol, (R)-(+)-pulegone, menthyl acetate and caryophyllene as constituent elements of peppermint oil by GC-MS analysis. We then examined the effect of each constituent element of peppermint oil on ambulatory activity in mice. Intraperitoneal administration of 1,8-cineol, menthone, isomenthone, menthol, (R)-(+)-pulegone, menthyl acetate and caryophyllene significantly increased ambulatory activity in mice, suggesting that these chemicals are the behaviorally active elements of peppermint oil. Intravenous administration of these substances to mice induced a significant increase in ambulatory activity at much lower doses. The present study provides further evidence demonstrating that EOs possess pharmacological actions on behavior. In addition, our finding revealed that the action of peppermint oil comes from its constituent elements.


Assuntos
Monoterpenos , Atividade Motora/efeitos dos fármacos , Parassimpatolíticos/farmacologia , Óleos de Plantas/farmacologia , Animais , Antipruriginosos/farmacologia , Monoterpenos Bicíclicos , Relação Dose-Resposta a Droga , Masculino , Mentha piperita , Mentol/farmacologia , Camundongos , Camundongos Endogâmicos ICR , Atividade Motora/fisiologia , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Parassimpatolíticos/análise , Óleos de Plantas/análise , Terpenos/farmacologia
19.
Inflammation ; 25(2): 69-73, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11321361

RESUMO

The TGF-beta1(-/-) mouse is a murine model for systemic autoimmune disease. The aim of this study is to elucidate the immunological mechanism that leads to multifocal tissue inflammation and autoantibody production in TGF-beta1(-/-) mice. Heart, lung, liver, and salivary gland from TGF-beta1(-/-) were assessed for CD154 expression by RT-PCR and immunohistochemistry. Compared to wild-type littermates, CD154 expression was elevated in all tissues studied. Furthermore, IL-12 mRNA was expressed in the salivary gland and heart of TGF-beta1(-/-) mice and not in wild-type littermates. This suggests that the CD154 pathway is activated in these tissues. This shows that TGF-beta1 regulates CD154 expression leading to spontaneous IL-12 production and autoimmunity.


Assuntos
Ligante de CD40/genética , Ligante de CD40/metabolismo , Fator de Crescimento Transformador beta/genética , Animais , Autoimunidade , Imuno-Histoquímica , Inflamação/etiologia , Inflamação/genética , Inflamação/imunologia , Interleucina-12/biossíntese , Fígado/imunologia , Fígado/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocárdio/imunologia , Miocárdio/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Glândulas Salivares/imunologia , Glândulas Salivares/metabolismo , Linfócitos T/imunologia , Distribuição Tecidual , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima
20.
Jpn J Ophthalmol ; 42(1): 41-5, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9507364

RESUMO

This article reports the first case of phakomatous choristoma of the eyelid in Japan. The tumor occurred in a 2-week-old boy and was located in the left lower lid near the inner canthus. An immunohistochemical study of this rare, congenital tumor was performed. The immunohistochemical analysis revealed that the epithelial cells of this tumor showed positive staining for vimentin, S-100 protein, and neuron-specific enolase, while they had no immunoreactivity for cytokeratin, glial fibrillary acidic protein, epithelial membrane antigen, or a macrophage marker. Both the epithelial cells and the central contents of the islands in this tumor showed positive staining with anti-human alpha crystallin monoclonal mouse IgG. These results strongly indicated that a phakomatous choristoma was of a lenticular origin.


Assuntos
Coristoma/patologia , Doenças Palpebrais/patologia , Cristalino , Coristoma/metabolismo , Cristalinas/metabolismo , Doenças Palpebrais/metabolismo , Humanos , Técnicas Imunoenzimáticas , Recém-Nascido , Masculino , Fosfopiruvato Hidratase/metabolismo , Proteínas S100/metabolismo , Vimentina/metabolismo
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