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1.
Rev Sci Instrum ; 85(11): 11E814, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430379

RESUMO

A fluctuation analysis technique using analytic signals is proposed. Analytic signals are suitable to characterize a single mode with time-dependent amplitude and frequency, such as an MHD mode observed in fusion plasmas since the technique can evaluate amplitude and frequency at a specific moment without limitations of temporal and frequency resolutions, which is problematic in Fourier-based analyses. Moreover, a concept of instantaneous phase difference is newly introduced, and error of the evaluated phase difference and its error reduction techniques using conditional/ensemble averaging are discussed. These techniques are applied to experimental data of the beam emission spectroscopic measurement in the Heliotron J device, which demonstrates that the technique can describe nonlinear evolution of MHD instabilities. This technique is widely applicable to other diagnostics having necessity to evaluate phase difference.

2.
Rev Sci Instrum ; 83(10): 10D535, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23126873

RESUMO

This paper describes the measurement of the density fluctuation using beam emission spectroscopy in Heliotron J, having the non-symmetrical helical-magnetic-axis configuration. In order to optimize the sightlines, the numerical calculations are carried out to estimate the spatial resolution and the observation location. When a tangential neutral beam is used as diagnostic one, suitable sightlines from the newly installed diagnostic port are selected whose spatial resolution Δρ is less than ± 0.07 over the entire plasma region. Modification of the interference filter and the detection systems enables us to measure the radial profile of the density fluctuation. Each of the three coherent modes due to the fast-ion-driven magnetohydrodynamic instabilities has different radial structure of the density fluctuation.


Assuntos
Análise Espectral/métodos , Hidrodinâmica , Fenômenos Magnéticos , Dispositivos Ópticos , Análise Espectral/instrumentação , Fatores de Tempo
3.
Xenobiotica ; 35(6): 589-602, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16192110

RESUMO

Valsartan is known to be excreted largely as unchanged compound and is minimally metabolized in man. Although the only notable metabolite is 4-hydroxyvaleryl metabolite (4-OH valsartan), the responsible enzyme has not been clarified at present. The current in vitro studies were conducted to identify the cytochrome P450 (CYP) enzymes involved in the formation of 4-OH valsartan. Valsartan was metabolized to 4-OH valsartan by human liver microsomes and the Eadie-Hofstee plots were linear. The apparent Km and Vmax values for the formation of 4-OH valsartan were 41.9-55.8 microM and 27.2-216.9 pmol min(-1) mg(-1) protein, respectively. There was good correlation between the formation rates of 4-OH valsartan and diclofenac 4'-hydroxylase activities (representative CYP2C9 activity) of 11 individual microsomes (r = 0.889). No good correlation was observed between any of the other CYP enzyme marker activities (CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4 and CYP4A). Among the recombinant CYP enzymes examined (CYPs 1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, 3A4, 3A5 and 4A11), CYP2C9 notably catalysed 4-hydroxylation of valsartan. For the specific CYP inhibitors or substrates examined (furafylline, diclofenac, S(+)-mephenytoin, quinidine and troleandomycin), only diclofenac inhibited the formation of 4-OH valsartan. These results showed that CYP2C9 is the only form responsible for 4-hydroxylation of valsartan in human liver microsomes. Although CYP2C9 is involved in valsartan metabolism, CYP-mediated drug-drug interaction between valsartan and other co-administered drugs would be negligible.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Microssomos Hepáticos/metabolismo , Tetrazóis/metabolismo , Valina/análogos & derivados , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacocinética , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP2C9 , Sistema Enzimático do Citocromo P-450/genética , Diclofenaco/metabolismo , Diclofenaco/farmacocinética , Diclofenaco/farmacologia , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Humanos , Hidroxilação , Cinética , Microssomos Hepáticos/efeitos dos fármacos , Proadifeno/farmacologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tetrazóis/farmacocinética , Valina/metabolismo , Valina/farmacocinética , Valsartana
4.
Jpn J Ophthalmol ; 45(4): 375-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11485769

RESUMO

BACKGROUND: Ligneous conjunctivitis is a rare condition characterized by chronic, recurrent conjunctivitis associated with pseudomembrane, and it may involve other mucous membranes in the mouth, nasopharynx, trachea, and vagina. We examined and treated a case of presumed ligneous conjunctivitis. CASE: The patient was a 10-year-old boy. His chief complaints were visual impairment, discomfort, and discharge, but no itching in his eyes. His upper eyelids appeared thick without swelling. He had a past history of surgery for lid entropion. His two siblings had similar follicular conjunctivitis. OBSERVATIONS: This case exhibited several characteristics of ligneous conjunctivitis, such as large follicles, recurrent pseudomembrane and normal level IgE in the serum. Indispensable characteristics of vernal keratoconjunctivitis, strong itching, and extensive papillary formation, were not found. In spite of the lack of woody hardness of the conjunctiva, other clinical findings led to the diagnosis of ligneous conjunctivitis. Definite histological diagnosis was not obtained, because of the lack of common histological characteristics among previously reported cases with ligneous conjunctivitis. The boy had developed corticosteroid glaucoma after instillation of dexamethasone 0.1% for 7 months at a previous time. We successfully treated this case with combined instillation of fluorometholon and cyclosporin after trabeculotomy. CONCLUSIONS: Ligneous conjunctivitis must be considered as one type of differential diagnosis of vernal keratoconjunctivitis. Cyclosporin is an effective alternative for the treatment of ligneous conjunctivitis, especially in a case with a possible history of corticosteroid glaucoma.


Assuntos
Conjuntivite/complicações , Criança , Terapia Combinada , Conjuntivite/diagnóstico , Conjuntivite/terapia , Ciclosporina/uso terapêutico , Células Epiteliais/patologia , Fluormetolona/uso terapêutico , Humanos , Masculino , Membranas/patologia , Trabeculectomia
5.
Org Lett ; 2(24): 3883-5, 2000 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-11101444

RESUMO

[reaction: see text] alpha-Methylation of 3 gave 5 as a major product whereas 4 gave 6 predominantly, although both 3 and 4 have an (S)-chiral center at C(3). This indicates that chirality at C(2) in 3 and 4 was memorized in the corresponding intermediate enolates and the induced chirality made a major contribution in the stereochemical course of the reaction, while chirality at the adjacent chiral center C(3) had little effect.


Assuntos
Isoleucina/análogos & derivados , Isoleucina/química , Alquilação , Cristalografia por Raios X , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Estereoisomerismo
7.
Am J Ophthalmol ; 130(1): 131-4, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11004280

RESUMO

PURPOSE: To determine the optical coherence tomographic images that are commonly observed in eyes with choroidal osteoma (choroidal ossification). METHODS: Three patients with choroidal osteoma were examined by optical coherence tomography. RESULTS: We found two optical coherence tomographic patterns in the eyes with choroidal osteoma. First, multiple tracks of high refractivity were present posterior to the tumor lesion. Second, thick and irregular plate-like, high-signal intensity areas were present in the choroid in the region of the tumor. CONCLUSIONS: Optical coherence tomography can be useful in the diagnosis of choroidal osteoma.


Assuntos
Neoplasias Ósseas/diagnóstico , Neoplasias da Coroide/diagnóstico , Técnicas de Diagnóstico Oftalmológico , Ossificação Heterotópica/diagnóstico , Osteoma/diagnóstico , Adulto , Idoso , Feminino , Humanos , Interferometria/métodos , Luz , Masculino , Tomografia/métodos , Tomografia Computadorizada por Raios X , Ultrassonografia
9.
J Toxicol Sci ; 25 Spec No: 51-62, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11349455

RESUMO

Doses of 0, 30 and 60 mg/kg/day of fadrozole hydrochloride (Afema: non-steroidal aromatase inhibitor, antitumor agent) were given perorally by gavage to HanIbm WIST male rats from 6 or 8 weeks of age for 2 weeks, and from 6 weeks of age for 4 weeks. In all treatment groups, reduced weights of seminal vesicle, prostate and epididymis, and degeneration/necrosis of the pachytene spermatocytes in stages VII or VIII seminiferous tubules, were dose-relatedly observed. Effects could also be assessed quantitatively by staging analysis with the result of a reduction in the numbers of stage VII pachytene spermatocytes at 30 and 60 mg/kg/day. Epididymal sperm examination revealed no treatment-related changes in any groups. The effects of 4-week treatment on male reproductive organs were similar to those of 2-week treatment at the same dose levels, except for the weights of seminal vesicle and prostate, which were more reduced by 4-week treatment than by 2-week treatment. There was no notable difference in detectability of toxicity in male reproductive organs between 2-week treatment from 6 weeks of age and 2-week treatment from 8 weeks of age. It was concluded that the changes observed in the rat male reproductive organs following 4 weeks of treatment with fadrozole hydrochloride could be detected also with 2 weeks of treatment.


Assuntos
Antineoplásicos Hormonais/toxicidade , Inibidores Enzimáticos/toxicidade , Fadrozol/toxicidade , Testículo/efeitos dos fármacos , Administração Oral , Animais , Antineoplásicos Hormonais/administração & dosagem , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Fadrozol/administração & dosagem , Masculino , Tamanho do Órgão/efeitos dos fármacos , Próstata/efeitos dos fármacos , Próstata/patologia , Ratos , Ratos Wistar , Glândulas Seminais/efeitos dos fármacos , Glândulas Seminais/patologia , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Testículo/patologia , Testículo/fisiopatologia , Fatores de Tempo , Testes de Toxicidade , Aumento de Peso/efeitos dos fármacos
10.
J Mol Evol ; 49(1): 122-9, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10368440

RESUMO

The beta-globin gene cluster of Wistar rat was extensively cloned and the embryonic genes were mapped and sequenced. Four overlapping lambda Dash recombinant clones cover about 31 kb and contain four nonadult beta-globin genes, 5'-epsilon1-gamma1-gamma2-psigamma3-3'. The epsilon1 and gamma2 are active genes, since their protein products were detected in the fetal stage of the rat (Iwahara et al., J Biochem 119:360-366, 1996). The gamma1 locus might be a pseudogene, since the ATA box in the promoter region is mutated to GTA; however, no other defect is observed. The psigamma3 locus is a truncated pseudogene because a 19-base deletion, which causes a shift of the reading frame, is observed between the second nucleotide of the putative codon 68 and codon 76. A sequence comparison suggests that the psigamma3 might be produced by a gene conversion event of the proto-gamma-globin gene set. Possible histories of the evolution of rat nonadult beta-globin genes are discussed.


Assuntos
Evolução Molecular , Globinas/genética , Família Multigênica , Sequência de Aminoácidos , Animais , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Dados de Sequência Molecular , Ratos , Ratos Wistar , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
11.
Gene ; 230(1): 91-9, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10196478

RESUMO

The highly heterogeneous rat hemoglobin system was investigated at the gene level. Two regions of the alpha-like globin gene cluster from a Wistar rat were isolated. Four lambda Dash recombinant clones carrying rat alpha-like globin genes were localized on two distinct gene regions. A region of approximately 16kb was found to contain the 5'-IIalpha1-psi theta 1-3' loci, and another of approximately 24kb the 5'-IIalpha2-psi theta2-psiI alpha3-3' loci. Both IIalpha1 and IIalpha2 are considered to be active, coding the IIalpha-globin chain. The nt sequences of IIalpha1 and IIalpha2 are identical except for six nt in the non-coding region. The psiI alpha3 locus is a truncated pseudogene. The putative promoter region of an alpha-like globin gene is joined directly to the third exon, homologous to that of Ialpha-globin cDNA. psi theta1 and psi theta2 are also pseudogenes, as evidenced by several deletions located in the protein-coding regions of these loci. The psi theta1 and psi theta2 loci exhibit extensive homology, but the restriction maps of these genes and their flanking regions differ considerably. Genomic Southern blot analyses of the total liver DNA from six rats showed the existence of three theta-globin-related genes, including psi theta1 and psi theta2. These results indicate that the two gene regions investigated are not allelic variants, but may be generated by block duplication. This is the first report of the existence of rodent theta-globin genes.


Assuntos
Globinas/genética , Animais , Sequência de Bases , Clonagem Molecular , Evolução Molecular , Duplicação Gênica , Dados de Sequência Molecular , Filogenia , Polimorfismo de Fragmento de Restrição , Regiões Promotoras Genéticas , Pseudogenes/genética , Ratos , Ratos Wistar , Mapeamento por Restrição , Alinhamento de Sequência
12.
Nippon Ganka Gakkai Zasshi ; 102(8): 509-14, 1998 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-9754022

RESUMO

During the past two years we studied the incidence of infection by eight members of the herpesvirus family in ocular samples (tear fluid, the aqueous, and the vitreous) using the polymerase chain reaction (PCR). A total of 31 ocular samples were collected from 22 eyes of 13 patients. The series comprised five cases of acute retinal necrosis, four of cytomegalovirus retinitis, three of proliferative diabetic retinopathy, and one of ocular malignant lymphoma. In 12 eyes of 9 patients with viral retinitis, causative viral DNA was detected either from the tear fluid (1/12, 8%), the aqueous (6/7, 86%), or the vitreous (1/1, 100%). In the fellow eyes free of viral retinitis, no viral DNA was detected in the samples (6 of tear fluid and one of the aqueous). Out of the other 4 patients without viral retinitis, viral DNA was detected in one patient with ocular malignant lymphoma. The findings show that PCR is a useful and sensitive method in the diagnosis of viral retinitis, but that it may give false positive results. The aqueous and the vitreous samples gave more positive results than tear fluid.


Assuntos
DNA Viral/análise , Retinite/diagnóstico , Retinite/virologia , Viroses/diagnóstico , Reações Falso-Positivas , Humanos , Reação em Cadeia da Polimerase , Viroses/virologia
14.
Am J Ophthalmol ; 122(6): 892-5, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8956649

RESUMO

PURPOSE: To describe a case of progressive outer retinal necrosis in a human immunodeficiency virus-negative immunosuppressed patient undergoing treatment for graft-versus-host disease after bone marrow transplantation. METHOD: Onset, course, and outcome of the patient's eye disease were analyzed. RESULTS: Findings and course were typical for the recently described progressive outer retinal necrosis syndrome. CONCLUSION: Progressive outer retinal necrosis is not limited to the acquired immunodeficiency syndrome but may occur in patients immunocompromised because of other conditions.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Síndrome de Necrose Retiniana Aguda/etiologia , Adolescente , Progressão da Doença , Fundo de Olho , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/etiologia , Soronegatividade para HIV , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/uso terapêutico , Leucemia Mieloide Aguda/terapia , Masculino , Síndrome de Necrose Retiniana Aguda/patologia , Síndrome de Necrose Retiniana Aguda/fisiopatologia , Acuidade Visual
15.
Biochemistry ; 34(41): 13398-406, 1995 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-7577926

RESUMO

A heme-binding protein (designated HBP23) has been purified from rat liver cytosol using heme-affinity chromatography and either reverse-phase high-performance liquid chromatography or sequential ion-exchange chromatography. The protein (23 kDa) binds heme with an affinity (Kd = 55 nM) higher than that of the abundant cytosolic heme-binding proteins, heme-binding protein (HBP)/liver fatty acid-binding protein (L-FABP) and the glutathione S-transferases (GSTs) (Kd = 100-200 nM). HBP23 is present in the cytosol of liver, kidney, spleen, small intestine, and heart, with the liver showing the highest content. A cDNA coding the 23-kDa protein was cloned using reverse transcription polymerase chain reaction with degenerative oligonucleotides derived from partial amino acid sequences. The cloned cDNA encoded 199 amino acids, and its amino acid sequence showed no homology to HBP/L-FABP, GSTs, or any other heme-binding proteins or hemeproteins. Homology search showed that HBP23 is highly homologous to mouse macrophage 23-kDa stress protein, which is inducible by oxidant stress in peritoneal macrophages [Ishii, T., Yamada, M., Sato, H., Matsue, M., Taketani, S., Nakayama, K., Sugita, Y., and Bannai, S. (1993) J. Biol. Chem. 268, 18633-18636]. Thioredoxin peroxidase as well as HBP23 and the mouse macrophage 23-kDa stress protein are members of the peroxiredoxin family, a recently recognized class of antioxidant proteins [Chae, H. Z., Chung, S. J., & Rhee, S. G. (1994) J. Biol. Chem. 269, 27670-27678]. An increase in HBP23 mRNA was observed in Hepa 1-6 cells after treatment with heme and cadmium and during liver regeneration after partial hepatectomy.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Proteínas de Transporte/metabolismo , Hemeproteínas/metabolismo , Fígado/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Transporte/biossíntese , Proteínas de Transporte/química , Cromatografia Líquida de Alta Pressão , Clonagem Molecular , Citosol/metabolismo , Primers do DNA , DNA Complementar/metabolismo , Feminino , Proteínas Ligantes de Grupo Heme , Hemeproteínas/biossíntese , Hemeproteínas/química , Humanos , Cinética , Espectrometria de Massas , Camundongos , Dados de Sequência Molecular , Peso Molecular , Especificidade de Órgãos , Reação em Cadeia da Polimerase , Ratos , Ratos Sprague-Dawley , Homologia de Sequência de Aminoácidos , Espectrofotometria
16.
J Biol Chem ; 269(17): 12654-61, 1994 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-8175675

RESUMO

Hemopexin (Hx) is an abundant acute-phase protein (APP) that binds heme with high affinity. In rat hepatic cells, the transcription rate of the Hx gene is increased by interleukin (IL)-1 and IL-6. To investigate the cis-acting regulatory elements (REs) responsive to these hormones, chloramphenicol acetyltransferase constructs of rat and human Hx gene sequences were tested in transiently transfected hepatoma cells. An IL-6-RE was identified in the promoter of both rat and human Hx genes, the function of which was dependent on the core sequence (CCGGGAA) common in other APP genes. The previously characterized Hx A element mediated a relatively minor cytokine response as compared with the Hx IL-6-RE. The human Hx A element, in contrast to the rat and human Hx IL-6-REs, was strongly trans-activated by cotransfected CAAT enhancer-binding proteins (C/EBP)-beta and -delta. The rat gene homolog of the human Hx A element was inactive as a cytokine RE and was minimally trans-activated by C/EBP isoforms. Results of electrophoretic mobility shift assays indicated that the Hx IL-6-RE is a binding site for the IL-6-inducible nuclear protein IL-6 RE-BP, which also binds to the conserved IL-6-REs of other APP genes and is distinct from C/EBP beta.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Hemopexina/genética , Interleucina-6/metabolismo , Proteínas Nucleares/metabolismo , Sequências Reguladoras de Ácido Nucleico , Animais , Sequência de Bases , Proteínas Estimuladoras de Ligação a CCAAT , Humanos , Interleucina-1/farmacologia , Masculino , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Ratos , Proteínas Recombinantes/metabolismo , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional , Células Tumorais Cultivadas
17.
J Biol Chem ; 269(9): 6851-8, 1994 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-8120047

RESUMO

Transcription of hemopexin (Hx) occurs predominantly in the liver. To investigate the contribution of the cis-acting enhancer element to the hepatocyte preferential expression, we performed chloramphenicol acetyl-transferase (CAT) assays in HepG2 cells. A strong enhancer element was identified by successive truncation to reside in the region -157/-104 from the cap site. The Hx region -145/-125 interacts with rat liver nuclear proteins, as shown by standard DNA-protein binding assays. The nucleotide sequence -141AGACTTTGACCT-130 includes, in reverse orientation, a direct repeat of the imperfect AGGTCA sequence, one of the recognition motifs of the steroid-thyroid hormone receptor superfamily. That this AGGTCA repeat is an enhancer core of the Hx element was affirmed by mutational analyses. In electrophoretic mobility shift assays, oligonucleotides, corresponding to binding regions of chicken ovalbumin upstream promoter transcription factor (COUP-TF) and apolipoprotein AI regulatory protein 1 (ARP-1) but not of hepatocyte nuclear factor-4 (HNF-4), competed with the Hx element for binding sites. Co-transfection analyses indicated that HNF-4 does not affect CAT expression whereas ARP-1 and COUP-TF repress it. Antibody supershift analyses suggested that HNF-4 and COUP-TF may not be major factors binding to the Hx element.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Hemopexina/genética , Fígado/metabolismo , Proteínas Nucleares/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Ligação Competitiva , Carcinoma Hepatocelular , Linhagem Celular , Núcleo Celular/metabolismo , Cloranfenicol O-Acetiltransferase/biossíntese , Cloranfenicol O-Acetiltransferase/metabolismo , DNA/química , DNA/metabolismo , Expressão Gênica , Hemopexina/biossíntese , Humanos , Cinética , Neoplasias Hepáticas , Dados de Sequência Molecular , Oligonucleotídeos/farmacologia , Ratos , Receptores de Esteroides/genética , Receptores dos Hormônios Tireóideos/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/metabolismo , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas
18.
Am J Cardiol ; 72(1): 36-40, 1993 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8390792

RESUMO

To elucidate the physiologic importance of atrial contribution in recently developed rate-responsive pacing, changes in cardiodynamics and neurohormonal factors were analyzed during exercise in patients with respiratory rate-dependent, rate-responsive atrial (AAIR; n = 6) and ventricular (VVIR; n = 9) demand mode pacemakers implanted for sick sinus syndrome. With increasing pacing rate during bicycle ergometer exercise, the AAIR group had significant increases in cardiac index (p < 0.05), left ventricular ejection fraction (p < 0.05), and ejection (p < 0.05) and peak filling (p < 0.05) rates; however, the VVIR group had a significant decrease in ejection fraction (p < 0.05), and an increase in cardiac index (p < 0.05) that was significantly less than in the AAIR group. At rest, the mean plasma concentrations of atrial natriuretic peptide (p < 0.005) and cyclic guanosine monophosphate (p < 0.05) were significantly greater in the VVIR group than in the AAIR group and normal subjects (n = 8). Atrial natriuretic peptide, norepinephrine, and cyclic adenosine and guanosine monophosphates were significantly greater (p < 0.05) during exercise, and atrial natriuretic peptide was significantly greater in the VVIR group (207.5 +/- 8.3 pg/ml) than in the AAIR group (116.4 +/- 51.5) and normal subjects (30.8 +/- 19.2; p < 0.05); this suggested a further increase in the nonphysiologic atrial overload with VVIR pacing. The data show both the neurohormonal and cardiodynamic importance of atrioventricular synchrony in rate-responsive pacing.


Assuntos
Função Atrial , Estimulação Cardíaca Artificial/métodos , Síndrome do Nó Sinusal/fisiopatologia , Idoso , Fator Natriurético Atrial/sangue , AMP Cíclico/sangue , GMP Cíclico/sangue , Epinefrina/sangue , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue , Marca-Passo Artificial , Síndrome do Nó Sinusal/sangue , Síndrome do Nó Sinusal/terapia , Função Ventricular Esquerda
19.
Environ Mol Mutagen ; 22(2): 101-6, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8359151

RESUMO

The micronucleus test is used widely as an in vivo short-term assay for potential carcinogens. In the present study, results of the micronucleus test were affected by cobalt dichloride pretreatment. Cobalt dichloride was used to induce erythropoietin, a growth factor for erythropoiesis. The increase in mutagen-induced micronucleus response following cobalt pretreatment, therefore, may have been due to a change in the rate of erythropoiesis. The greatest interaction between cobalt pretreatment and mutagen treatment for the induction of micronucleated polychromatic erythrocytes (MPCE) occurred when mice were injected with 1,1-dimethylhydrazine (DMH) 12-24 hr after pretreatment with cobalt dichloride and killed 30 hr later. Increased sensitivity of the micronucleus test was attributable to the administration of mutagen during the differentiation and multiplication of erythroblast, which is presumed to have been accelerated by pretreatment with cobalt dichloride. An increased induction of MPCE in the bone marrow by two chemicals--benzo(a)pyrene, 2-naphthylamine--was also observed following pretreatment with cobalt dichloride.


Assuntos
Cobalto/toxicidade , Eritropoese/efeitos dos fármacos , Testes para Micronúcleos/métodos , Mutagênicos/toxicidade , 2-Naftilamina/toxicidade , Animais , Benzo(a)pireno/toxicidade , Dimetilidrazinas/toxicidade , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fatores de Tempo
20.
J Toxicol Sci ; 17(4): 185-95, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1474613

RESUMO

The effect of estrogen on plasma membrane was investigated using the primary cultured rat hepatocytes treated with carbon tetrachloride (CCl4) and the isolated plasma membrane of rat liver. 17 beta-Estradiol (E2), at concentrations of 10(-10) M to 10(-4) M, 10(-8) M to 10(-6) M and 10(-12) M to 10(-4) M, had an inhibitory effect on the CCl4-induced leakage of glutamic oxaloacetic transaminase, glutamic pyruvic transaminase and lactate dehydrogenase, respectively from primary cultured rat hepatocytes. Diethylstilbestrol, which caused inhibition at a dose of 10(-4) M, did not inhibit any enzyme leakage at any further concentrations of 10(-12) M to 10(-6) M. In the isolated plasma membrane of rat liver, Mg(2+)- and Na+,K(+)-adenosine triphosphatase activity was increased by E2 treatment at concentrations of 10(-6) M and 10(-4) M.


Assuntos
Dietilestilbestrol/farmacologia , Estradiol/farmacologia , Fígado/efeitos dos fármacos , Progesterona/farmacologia , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Tetracloreto de Carbono/efeitos adversos , Membrana Celular/efeitos dos fármacos , Células Cultivadas , L-Lactato Desidrogenase/metabolismo , Fígado/enzimologia , Fígado/ultraestrutura , Masculino , Ratos
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