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1.
Anaesthesia ; 75(1): 37-44, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31556454

RESUMO

The inflationary non-invasive blood pressure monitor (iNIBP™) uses a new measurement method, whereby the cuff is slowly inflated whilst simultaneously sensing oscillations, to determine the diastolic blood pressure first and then the systolic pressure. It may measure blood pressure more quickly than the conventional non-invasive blood pressure monitor. We studied 66 patients undergoing general anaesthesia, comparing the time taken to measure the blood pressure between the two monitors at times when there were marked changes (increases or decreases by 30 mmHg or greater) in the systolic blood pressure. The median (IQR) [range]) time was significantly longer for the non-invasive blood pressure monitor (38.8 (31.5-44.7) [18.0-130.0] s) than for the iNIBP (14.6 (13.7-16.4) [11.5-35.5] s), p = 0.001, 95%CI for difference 22-25 s). We also studied 30 volunteers to evaluate the accuracy of the iNIBP, comparing it with the mercury sphygmomanometer. There was good agreement between the two monitors, with a mean difference of 0 (95% limit of agreement -12 to 11) mmHg for the systolic blood pressure. We also compared the degree of pain during cuff inflation between the automated non-invasive blood pressure and iNIBP monitors. Pain was significantly more for the non-invasive blood pressure monitor (22 of 30 volunteers had less pain with the iNIBP). We have shown that the iNIBP measured the blood pressure quicker than the conventional non-invasive blood pressure monitor and the speed of measurement was not significantly affected by marked changes in the blood pressure.


Assuntos
Determinação da Pressão Arterial/instrumentação , Determinação da Pressão Arterial/métodos , Estudos Cross-Over , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Tempo
2.
Occup Med (Lond) ; 70(9): 680-684, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33247305

RESUMO

BACKGROUND: The number of patients living with depression continues to increase in Japan. The economic effects of depression include loss of productivity due to both absenteeism and presenteeism. Gender differences have been reported in prevalence, onset pathways and subjective symptoms of depression. AIMS: To understand how workers with major depressive disorder (MDD) perceive problems in the workplace and examine gender differences in their self-perceived levels of functioning at work, noticed during the initial stages of depression. METHODS: This is a cross-sectional study of Japanese workers with MDD. Participants' self-perceived changes in the level of functioning at work were surveyed after the diagnosis during the first visit. The relationship between gender and changes in the level of functioning at work as initially perceived by the participants themselves was analysed using the chi-square test, supplemented by a residual analysis. RESULTS: We administered the survey to 147 workers with MDD. In terms of gender differences in initial self-perceived changes in the level of functioning at work, the proportion of men reporting reduced work efficiency was significantly higher than that of women, while the proportion of women reporting deterioration in relationships with colleagues and superiors was significantly higher than that of men. CONCLUSIONS: The findings suggest that greater attention to reduced work efficiency by men and to deterioration in work relationships by women with MDD should be essential components of self-care. Managers need to pay attention to the level of functioning and provide adequate social support for employees.


Assuntos
Depressão , Transtorno Depressivo Maior , Absenteísmo , Estudos Transversais , Feminino , Humanos , Japão , Masculino , Caracteres Sexuais , Inquéritos e Questionários , Local de Trabalho
3.
Phys Rev Lett ; 114(10): 105304, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25815943

RESUMO

The transverse acoustic impedance of superfluid ^{3}He was measured in the A1 and A2 phases up to 13 T to investigate the surface states in nonunitary superfluids. The temperature dependence of the impedance was much larger in the A1 phase than in the A2 phase. This nonsymmetric behavior indicates that momentum exchange with walls for spin-down surface states is quite different from that for spin-up surface states. The spin-dependent response might be a reflection of an essential feature of the nonunitary states where gap amplitudes depend on spin states. Weak-coupling theories ignore any spin-dependent processes and do not account for the nonsymmetric behavior.

4.
Anaesthesia ; 69(8): 878-82, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24866121

RESUMO

We studied 40 adult patients to see if cricoid pressure affected placement of the I-gel(™). In a randomised crossover design, the i-gel was placed with and without cricoid pressure, and we compared the success rate of adequate ventilation through the i-gel, time to placement and the rate of optimal position of the device between the two circumstances. Cricoid pressure significantly decreased the success rate of adequate ventilation through the i-gel (40 vs 34 patients) (p = 0.041, 95% CI for difference 4-26%), and significantly decreased the rate of the optimal position (39 vs 17 patients) (p < 0.001). The time to achieve adequate ventilation was significantly longer (p < 0.001) with cricoid pressure than without (median difference 8 s; 95% CI for median difference 3-12 s). Cricoid pressure significantly decreases the success rate of ventilation through the i-gel, but the success rate of ventilation through the i-gel is reasonably high.


Assuntos
Cartilagem Cricoide/fisiologia , Elastômeros , Máscaras Laríngeas , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão
5.
Nat Genet ; 11(2): 170-6, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7550345

RESUMO

Tay-Sachs and Sandhoff diseases are clinically similar neurodegenerative disorders. These two sphingolipidoses are characterized by a heritable absence of beta-hexosaminidase A resulting in defective GM2 ganglioside degradation. Through disruption of the Hexa and Hexb genes in embryonic stem cells, we have established mouse models corresponding to each disease. Unlike the two human disorders, the two mouse models show very different neurologic phenotypes. Although exhibiting biochemical and pathologic features of the disease, the Tay-Sachs model showed no neurological abnormalities. In contrast, the Sandhoff model was severely affected. The phenotypic difference between the two mouse models is the result of differences in the ganglioside degradation pathway between mice and humans.


Assuntos
Encéfalo/patologia , Gangliosídeos/metabolismo , Neurônios/patologia , Doença de Sandhoff/genética , Medula Espinal/patologia , Doença de Tay-Sachs/genética , beta-N-Acetil-Hexosaminidases/deficiência , beta-N-Acetil-Hexosaminidases/genética , Animais , Encéfalo/fisiopatologia , Sequência de Carboidratos , Modelos Animais de Doenças , Hexosaminidase A , Hexosaminidase B , Humanos , Camundongos , Camundongos Mutantes , Dados de Sequência Molecular , Neurônios/metabolismo , Fenótipo , Mapeamento por Restrição , Doença de Sandhoff/metabolismo , Doença de Sandhoff/patologia , Medula Espinal/metabolismo , Células-Tronco/fisiologia , Doença de Tay-Sachs/metabolismo , Doença de Tay-Sachs/patologia
6.
Phys Rev Lett ; 108(2): 025302, 2012 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-22324695

RESUMO

We have found that the surface specularity for 3He quasiparticle scattering is closely related to the superfluidity and the Kosterlitz-Thouless (KT) transition of 4He film adsorbed on the surface. The specularity is determined by measurements of the transverse acoustic impedance of bulk liquid 3He. The unique point of our system is that we can control the correlation among 4He atoms in the film by changing the pressure of the bulk 3He. The observed KT transition temperature is significantly suppressed by increasing the pressure, which suggests a strong correlation effect on KT transition.

7.
J Endocrinol Invest ; 35(7): 661-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21970822

RESUMO

BACKGROUND: Serum undercarboxylated osteocalcin (ucOC) is a biochemical bone marker of vitamin K insufficiency. It had been reported that bone resorption inhibitors tend to decrease the serum ucOC level in patients with primary osteoporosis. In rheumatoid arthritis (RA) patients, these results have never been reported. AIM: We investigated risk factors which could change serum ucOC level in post-menopausal women with RA (no.=100). SUBJECTS AND METHODS: Twenty patients received no bone resorption inhibitor (control), 30 received raloxifene (RLX), while 50 received alendronate (ALN). This cross-sectional study was limited to patients with low RA disease activity (Disease Activity Score-28 ≤3.2). We measured serum ucOC, and the data were analyzed by multivariable analysis, including ucOC and the other variables. RESULTS: Scheffe's F test demonstrated a significant difference in serum ucOC levels between controls and the RLX group (p<0.01), and between controls and the ALN group (p<0.01). Serum ucOC levels were low in both treated groups. An adjusted multivariate analysis was performed for the variables: bone resorption inhibitor use, serum alkaline phosphatase, glucocorticoid dose, age, estimated glomerular filtration rate and matrix metalloproteinase 3. As a result, serum ucOC inversely correlated with bone resorption inhibitor use (p<0.01) and oral glucocorticoid dose (p<0.01), which were independent risk factors of lowering ucOC. CONCLUSIONS: Bone resorption inhibitors and glucocorticoids were independent risk factors for lowering serum ucOC levels in post-menopausal RA patients.


Assuntos
Alendronato/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Conservadores da Densidade Óssea/efeitos adversos , Glucocorticoides/efeitos adversos , Osteocalcina/sangue , Cloridrato de Raloxifeno/efeitos adversos , Deficiência de Vitamina K/induzido quimicamente , Idoso , Idoso de 80 Anos ou mais , Alendronato/uso terapêutico , Artrite Reumatoide/sangue , Artrite Reumatoide/fisiopatologia , Biomarcadores/sangue , Conservadores da Densidade Óssea/uso terapêutico , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Estudos Transversais , Feminino , Taxa de Filtração Glomerular , Glucocorticoides/uso terapêutico , Humanos , Pessoa de Meia-Idade , Osteocalcina/metabolismo , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/etiologia , Pós-Menopausa , Cloridrato de Raloxifeno/uso terapêutico , Fatores de Risco , Índice de Gravidade de Doença , Deficiência de Vitamina K/sangue , Deficiência de Vitamina K/fisiopatologia
8.
J Endocrinol Invest ; 35(9): 796-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23135318

RESUMO

AIM: The serum undercarboxylated osteocalcin (ucOC) level, a biochemical bone marker of vitamin K insufficiency, is often affected by anti-osteoporosis drugs. There have been no reports regarding the relationship between ucOC and teriparatide. SUBJECTS AND METHODS: We conducted a prospective observational study of 26 female rheumatoid arthritis (RA) patients. The patients were divided into 3 groups: those who underwent a direct switch from anti-resorptive drugs to teriparatide (12 cases), those who started teriparatide without pre-treatment (5 cases), and the control patients (9 cases). The median age (interquartile range) of the patients in each group was 75 (67-77), 82 (78-84), and 69 (62-80) yr, respectively. All patients, except controls, received 48-week treatments of teriparatide. We analyzed the median 48-week changes from baseline of the serum ucOC levels with the Steel-Dwass method. RESULTS: The median change from baseline in the direct switch group was higher than that in other groups (p<0.05). CONCLUSIONS: The serum ucOC levels increased with treatment of teriparatide in elderly RA patients, especially when the patients received pre-treatment.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Biomarcadores/sangue , Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Ácidos Carboxílicos/metabolismo , Osteocalcina/sangue , Teriparatida/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Artrite Reumatoide/sangue , Artrite Reumatoide/complicações , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/etiologia , Prognóstico , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Deficiência de Vitamina K/sangue , Deficiência de Vitamina K/induzido quimicamente
9.
Acta Gastroenterol Belg ; 85(3): 477-483, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35770281

RESUMO

Background and study aims: The gastrointestinal (GI) tract is the most common site of extra-nodal involvement for non-Hodgkin's lymphoma (NHL). The features of GI NHLs remain unclear. The aim of this study was to clarify endoscopic characteristics of GI NHLs. Patients and methods: We retrospectively analyzed the morphological characteristics of 63 GI malignant lymphomas other than mucosa-associated lymphoid tissue lymphoma. Lesions were diagnosed between 2005 and 2020. Macroscopic findings were classified into five subtypes: superficial (S); protruding without ulcer (P); protruding with ulcer (PU); fungating (F); and multiple nodules (MN). Results: Thirty-one lesions in the stomach were classified as S type in 3 cases (9.6%), P type in 6 (19%), PU type in 13 (42%), and F type in 9 (29%). In the stomach, the ulcerated phenotype was more frequent for diffuse large B-cell lymphoma (DLBCL) (89.5%) than for other histological types (41.7%; P = 0.01). In the intestine, 23 tumors were classified as S type in 4 cases (17%), P type in 1 (4%), PU type in 6 (26%), F type in 1 (4%), and MN in 11 (48%). Eleven of the 14 cases (78.6%) of intestinal follicular lymphoma lesions showed MN type. In the colon, eight tumors were classified as S type in 2 cases (25%), P type in 2 (25%), PU type in 1 (13%), and F type in 3 (38%). Conclusion: We have clarified the endoscopic features of GI NHL using macroscopic classifications. The ulcerated phenotype was the most frequent endoscopic finding for DLBCL.


Assuntos
Neoplasias Gastrointestinais , Linfoma de Zona Marginal Tipo Células B , Linfoma Difuso de Grandes Células B , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/patologia , Humanos , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Linfoma de Zona Marginal Tipo Células B/patologia , Linfoma Difuso de Grandes Células B/patologia , Estudos Retrospectivos , Úlcera
10.
Sci Rep ; 11(1): 4277, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608561

RESUMO

We report the first observation of room temperature spontaneous electric polarization in an electronic ferroelectric material, a YbFe2O4 single crystal. The observation was based on second harmonic generation (SHG), a nonlinear optical process. Tensor analysis of the SHG signal revealed that this material has a polar charge superstructure with Cm symmetry. This result settles the long-term discussion on the uncertainty about electronic ferroelectric properties, including the charge order structure. We present a complete picture of the polar charge ordering of this material via consistent results from two different characterization methods. The SHG signal shows the same temperature dependence as the superlattice signal observed in neutron diffraction experiments. These results prove ferroelectric coupling to electron ordering in YbFe2O4, which results in electronic ferroelectricity which is enabled by the real space ordering of iron cations with different valences. The existence of electronic ferroelectricity holds promise for future electronics technologies where devices run a thousand times faster than frequency of the present CPU (a few gigahertz) embedded in smartphones, etc.

11.
Phys Rev Lett ; 103(15): 155301, 2009 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-19905647

RESUMO

We measured the transverse acoustic impedance of superfluid 3He-B with a wall coated by several layers of 4He. The coating is known to enhance the specularity in quasiparticle scattering by the wall. We found a new anomaly, a bump and a peak, in the temperature dependence of the transverse acoustic impedance. This agrees with a theoretical calculation using a partially specular wall boundary condition. The new anomaly is shown to arise from a change in the surface density of states by coating and the scattering of thermally occupied surface bound states to other states. The change is towards the density of states of Majorana cone in the specular limit.

12.
Transplant Proc ; 51(1): 20-24, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30655130

RESUMO

BACKGROUND: Ex vivo machine perfusion (MP) has been reported as a possibly method to rescue discarded organs. The main aim of this study was to report an initial experience in Spain using MP for the rescue of severely marginal discarded liver grafts, and to, secondarily, define markers of viability to test the potential applicability of these devices for the real increase in the organ donor pool. METHODS: The study began in January 2016. Discarded grafts were included in a research protocol that consisted of standard retrieval followed by 10 hours of cold ischemia. Next, either normothermic (NMP) or controlled subnormothermic (subNMP) rewarming was chosen randomly. Continuous measurements of portal-arterial pressure and resistance were screened. Lactate, pH, and bicarbonate were measured every 30 minutes. The perfusion period was 6 hours, after which the graft was discarded and evaluated as potentially usable, but never implanted. Biopsies of the donor and at 2, 4, and 6 hours after ex vivo MP were obtained. RESULTS: A total of 4 grafts were included in the protocol. The first 2 grafts were perfused by NMP and grafts 3 and 4 by subNMP. The second and third grafts showed a clear trend toward optimal recovery and may have been used. Lactate dropped to levels below 2.5 mmol/L with stable arterial and portal pressure and resistance. Clear biliary output started during MP. Biopsies showed an improvement of liver architecture with reduced inflammation at the end of the perfusion. CONCLUSION: This preliminary experience has demonstrated the potential of MP devices for the rescue of severely marginal liver grafts. Lactate and biliary output were useful for viability testing of the grafts. The utility of NMP or subNMP protocols requires further research.


Assuntos
Transplante de Fígado/métodos , Preservação de Órgãos/métodos , Perfusão/métodos , Doadores de Tecidos/provisão & distribuição , Transplantes , Isquemia Fria/métodos , Circulação Extracorpórea/métodos , Humanos , Reaquecimento/métodos , Espanha , Transplantes/patologia
13.
Br J Anaesth ; 100(4): 544-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18238836

RESUMO

BACKGROUND: We studied whether laryngoscopy and tracheal intubation were easier when using the Pentax-AWS (Tokyo, Japan), a new videolaryngoscope, than when applying the Macintosh laryngoscope, during manual in-line neck stabilization. METHODS: In 203 anaesthetized patients with manual in-line neck stabilization, we inserted the Pentax-AWS and a Macintosh laryngoscope, in turn, and recorded the view of the glottis and time taken to laryngoscopy. The success rate of tracheal intubation (within 120 s) and time to intubation were also recorded. RESULTS: The view of the glottis was significantly better with the Pentax-AWS than with the Macintosh laryngoscope (P<0.001). For the Macintosh laryngoscope, the view was obscured in 22 of 203 patients (11%) (Grade 3 in 21 patients and Grade 4 in one patient), whereas for the Pentax-AWS, the glottis was always clearly seen (Grade 1). Time taken to see the glottis with the Pentax-AWS [mean (sd): 6.0 (3.1) s] was significantly shorter than with the Macintosh laryngoscope [11.0 (5.0) s] (95% CI for difference: 4-6 s). The success rate of tracheal intubation with the Pentax-AWS (all of 99 patients) was significantly higher than with the Macintosh laryngoscope (93 of 104 patients) (P=0.001). Time taken for intubation was similar between the Macintosh laryngoscope [51 (27) s] and the Pentax-AWS [54 (14) s] (95% CI for difference: -9 to 3 s). CONCLUSIONS: In patients with stabilized neck, the Pentax-AWS provided a better view of the glottis and a higher success rate of tracheal intubation, compared with the conventional Macintosh laryngoscope.


Assuntos
Movimentos da Cabeça , Imobilização/métodos , Intubação Intratraqueal/instrumentação , Laringoscópios , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Cross-Over , Equipamentos Descartáveis , Desenho de Equipamento , Feminino , Tecnologia de Fibra Óptica/instrumentação , Humanos , Intubação Intratraqueal/métodos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Gravação em Vídeo
14.
Toxicol Lett ; 281: 152-157, 2017 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-28947270

RESUMO

Evaluating myelotoxicity is essential for ensuring the safety of novel drugs before they are approved for clinical applications. Although in vivo prediction of the maximum tolerated doses (MTDs) of anticancer drugs is usually performed in rodents, the results are not always applicable to clinical treatment because drugs may have different effects in human and rodent cells. Previously, we generated a human IL-3 and GM-CSF transgenic humanized mouse (hu-IL-3/GM Tg), in which human granulocytes effectively differentiated after hematopoietic stem cell transplantation. In this study, we established a novel in vivo preclinical evaluation model for predicting human myelotoxicity of anticancer drugs using these hu-IL-3/GM Tg mice. The myelotoxicity was investigated by kinetic flow cytometry of human or murine granulocytes and by colony-forming unit granulocyte/macrophage (CFU-GM) assays. In both in vivo and in vitro analyses, topotecan was more myelotoxic to human than murine granulocytes. In contrast, oxaliplatin was more myelotoxic to murine granulocytes. The level of myelotoxicity of paclitaxel treatment was comparable between human and mouse cells. These results demonstrate that our humanized mouse model can simultaneously evaluate myelotoxicity against human and mouse cells in vivo, and provides an effective preclinical tool for predicting appropriate doses of anticancer agents for clinical treatment.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Paclitaxel/toxicidade , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaio de Unidades Formadoras de Colônias , Relação Dose-Resposta a Droga , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Granulócitos/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Interleucina-3/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Testes de Toxicidade
15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 73(3 Pt 1): 032601, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16605581

RESUMO

Dynamics of capillary condensation of liquid 4He in various density silica aerogels was investigated systematically. Interfaces were clearly visible when bulk liquid was rapidly sucked into the aerogel. Time evolution of the interface positions was consistent with the Washburn model and their effective pore radii were obtained. Condensation was a single step in a dense aerogel and two steps in a low density aerogel. Crossover between the two types of condensation was observed in an intermediate density aerogel. Variety of the dynamics may be the manifestation of the fractal nature of aerogels which had a wide range of distribution of pore radii.

17.
Phys Rev E ; 93(5): 052806, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27300963

RESUMO

To investigate whether it is possible to control the wetting of ^{4}He crystals on a wall in superfluid, the contact angles of ^{4}He crystals were measured on rough and smooth walls at very low temperatures. A rough wall was prepared in a simple manner in which a commercially available coating agent for car mirrors, which makes the glass surface superhydrophobic, was used to coat a glass plate. The contact angles of ^{4}He crystals were increased by approximately 10^{∘} on the rough wall coated with the agent. Therefore, the increase in the repellency of ^{4}He crystals in superfluid was demonstrated to be possible on a very rough surface. The enhancement of the contact angles and a scanning electron microscopy image of the coated surface both suggest that a Cassie-Baxter state of ^{4}He crystals was realized on the surface; the crystals did not have full contact with the wall, but entrapped superfluid was present beneath the crystals in the hollow parts of the rough wall.

18.
Circulation ; 99(22): 2942-50, 1999 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-10359740

RESUMO

BACKGROUND: It has been suggested that intracellular Ca2+ overload in cardiac myocytes leads to the development of diabetic cardiomyopathy. Troglitazone, an insulin-sensitizing agent, is a promising therapeutic agent for diabetes and has been shown to prevent diabetes-induced myocardial changes. To elucidate the underlying mechanism of troglitazone action on cardiac myocytes, the effects of troglitazone on voltage-dependent Ca2+ currents were examined and compared with classic Ca2+ antagonists (verapamil and nifedipine). METHODS AND RESULTS: Whole-cell voltage-clamp techniques were applied in single guinea pig atrial myocytes. Under control conditions with CsCl internal solution, the voltage-dependent Ca2+ currents consisted of both T-type (ICa,T) and L-type (ICa,L) Ca2+ currents. Troglitazone effectively reduced the amplitude of ICa,L in a concentration-dependent manner. Troglitazone also suppressed ICa,T, but the effect of troglitazone on ICa,T was less potent than that on ICa,L. The current-voltage relationships for ICa,L and the reversal potential for ICa,L were not altered by troglitazone. The half-maximal inhibitory concentration of troglitazone on ICa,L measured at a holding potential of -40 mV was 6.3 micromol/L, and 30 micromol/L troglitazone almost completely inhibited ICa,L. Troglitazone 10 micromol/L did not affect the time courses for inactivation of ICa,L and inhibited ICa,L mainly in a use-independent fashion, without shifting the voltage-dependency of inactivation. This effect was different from those of verapamil and nifedipine. Troglitazone also reduced isoproterenol- or cAMP-enhanced ICa,L. CONCLUSIONS: These results demonstrate that troglitazone inhibits voltage-dependent Ca2+ currents (T-type and L-type) and then antagonizes the effects of isoproterenol in cardiac myocytes, thus possibly playing a role in preventing diabetes-induced intracellular Ca2+ overload and subsequent myocardial changes.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/fisiologia , Cromanos/farmacologia , Hipoglicemiantes/farmacologia , Miocárdio/metabolismo , Tiazóis/farmacologia , Tiazolidinedionas , Animais , Canais de Cálcio Tipo L , Canais de Cálcio Tipo T , Cardiotônicos/farmacologia , AMP Cíclico/farmacologia , Condutividade Elétrica , Cobaias , Isoproterenol/farmacologia , Cinética , Miocárdio/citologia , Nifedipino/farmacologia , Troglitazona , Verapamil/farmacologia
19.
Diabetes ; 36(3): 256-60, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2879756

RESUMO

Directional blood flow in pancreatic islets may be important for regulation of islet hormone release. We therefore perfused an isolated canine pancreas via the celiac artery (arterial perfusion) and then via the portal vein (venous perfusion) in the same pancreas. Basal insulin and glucagon levels and their rate of release in response to 10 mM arginine, 11 mM glucose, 500 pg/ml somatostatin, or 500 pg/ml glucagon were similar under both conditions. However, the inhibition of glucagon release due to somatostatin and its recovery after the cessation of somatostatin infusion was poor in the case of venous perfusion. The basal somatostatin level and its release in response to 10 mM arginine, 11 mM glucose, and 500 pg/ml glucagon during venous perfusion was significantly higher than that during arterial perfusion. From these results, it is speculated that the directional blood flow in pancreatic islets may not be essential for regulation of hormone release from the canine pancreas or that such directionality does not exist in canine pancreatic islets, and that a considerable portion of released somatostatin may be taken up by the pancreas located downstream--probably in the exocrine pancreas.


Assuntos
Glucagon/metabolismo , Insulina/metabolismo , Ilhotas Pancreáticas/irrigação sanguínea , Somatostatina/metabolismo , Animais , Arginina/farmacologia , Artéria Celíaca , Cães , Glucose/farmacologia , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Perfusão , Veia Porta
20.
Mol Immunol ; 35(5): 317-26, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9747891

RESUMO

To investigate the role of Fas in experimental autoimmune encephalomyelitis (EAE) in mice, we examined the susceptibility of EAE in C57BL/6 (B6).lpr mice lacking Fas. The frequency of myelin oligodendrocyte glycoprotein (MOG)-induced EAE in B6.lpr mice was significantly lower than that in B6 mice (19% vs 94%). However, no significant difference was observed between them in either the lymphocyte proliferation response or antibody reactivity to MOG. In addition, the histological examination and semiquantitative reverse transcriptase polymerase chain reaction analysis revealed that the infiltration of inflammatory cells and the up-regulation of gene expression for inflammatory cytokines occurred in the central nervous system (CNS) of B6.lpr mice immunized with MOG, even if they showed no clinical sign. These results indicate that Fas may contribute to the pathogenesis of EAE and may play a crucial role in the expansion of inflammation and/or myelin destruction in the CNS rather than in the activation of encephalitogenic T cells in the periphery and/or the breakdown of blood brain barrier.


Assuntos
Encefalomielite Autoimune Experimental/etiologia , Encefalomielite Autoimune Experimental/imunologia , Receptor fas/fisiologia , Animais , Antígenos de Superfície/imunologia , Apoptose , Cruzamentos Genéticos , Citocinas/genética , Doenças Desmielinizantes/genética , Doenças Desmielinizantes/imunologia , Doenças Desmielinizantes/patologia , Progressão da Doença , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/patologia , Epitopos/imunologia , Feminino , Regulação da Expressão Gênica/imunologia , Imunização , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos MRL lpr , Proteínas da Mielina , Glicoproteína Associada a Mielina/administração & dosagem , Glicoproteína Associada a Mielina/imunologia , Glicoproteína Mielina-Oligodendrócito , Oligodendroglia/imunologia , RNA Mensageiro/biossíntese , Medula Espinal/patologia , Regulação para Cima/genética , Regulação para Cima/imunologia , Receptor fas/genética
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