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1.
Anaesthesia ; 72(10): 1251-1264, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28737223

RESUMO

We conducted both conventional pairwise and Bayesian network meta-analyses to compare the clinical properties of supraglottic airway devices in children. We searched six databases for randomised clinical trials. Our primary end-points were oropharyngeal leak pressure, risk of insertion failure at first attempt, and blood staining risk. The risk of device failure, defined as the abandonment of the supraglottic airway device and replacement with a tracheal tube or another device, was also analysed. Sixty-five randomised clinical trials with 5823 participants were identified, involving 16 types of supraglottic airway device. Network meta-analysis showed that the i-gel™, Cobra perilaryngeal airway™ and Proseal laryngeal mask airway (LMA® -Proseal) showed statistically significant differences in oropharyngeal leak pressure compared with the LMA® -Classic, with mean differences (95% credible interval, CrI) of 3.6 (1.9-5.8), 4.6 (1.7-7.6) and 3.4 (2.0-4.8) cmH2 O, respectively. The i-gel was the only device that significantly reduced the risk of blood staining of the device compared with the LMA-Classic, with an odds ratio (95%CrI) of 0.46 (0.22-0.90). The risk (95%CI) of device failure with the LMA-Classic, LMA® -Unique and LMA-Proseal was 0.36% (0.14-0.92%), 0.49% (0.13-1.8%) and 0.50% (0.23-1.1%), respectively, whereas the risk (95%CI) of the i-gel and PRO-Breathe was higher, at 3.4% (2.5-4.7%) and 6.0% (2.8-12.5%), respectively. The risk, expressed as odds ratio (95%CrI), of insertion failure at first attempt, was higher in patients weighing < 10 kg at 5.1 (1.6-20.1). We conclude that the LMA-Proseal may be the best supraglottic airway device for children as it has a high oropharyngeal leak pressure and a low risk of insertion. Although the i-gel has a high oropharyngeal leak pressure and low risk of blood staining of the device, the risk of device failure should be evaluated before its routine use can be recommended.


Assuntos
Máscaras Laríngeas , Pressão do Ar , Anestesia Geral/instrumentação , Teorema de Bayes , Criança , Desenho de Equipamento , Falha de Equipamento , Humanos , Máscaras Laríngeas/efeitos adversos , Orofaringe , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos
2.
Clin Genet ; 88(2): 155-60, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25046119

RESUMO

In current practice of clinical genetics, molecular diagnosis has become more widely used than ever before. DNA diagnosis is important for appropriate medical care of the patient, and proper genetic counseling to the family. However, genetic testing of orphan disease cannot always be performed easily. In multiple congenital anomalies (MCA) syndromes by monogenic cause, the broad mutational spectrum and large size of responsible genes often make molecular diagnosis expensive and cumbersome. We solve this problem with on-demand genetic testing by CHIPS (CEL nuclease mediated heteroduplex incision with polyacrylamide gel electrophoresis and silver staining) technology, which is the ultimately conventional and economical mutation screening system. In this article, we show eight patients with MCA syndromes who were recently treated at our hospital, and demonstrate that CHIPS successfully offers efficient and inexpensive genetic testing and facilitates clinical genetic service in our local region.


Assuntos
Anormalidades Múltiplas/diagnóstico , Testes Genéticos/métodos , Técnicas de Diagnóstico Molecular/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Anormalidades Múltiplas/genética , Adulto , Criança , Feminino , Aconselhamento Genético , Humanos , Lactente , Recém-Nascido , Masculino , Mutação/genética
3.
Eur J Phys Rehabil Med ; 48(1): 47-55, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22071503

RESUMO

BACKGROUND: For spastic upper limb hemiparesis after stroke, we developed triple-element protocol of botulinum toxin type A (BoNTA) injection, low-frequency repetitive transcranial magnetic stimulation (LF-rTMS), and intensive occupational therapy (OT). Aim. To investigate the safety and feasibility of the protocol. Design. A preliminary study. Setting. At a university hospital. Population. Fourteen post-stroke patients with spastic upper limb hemiparesis (mean age: 54.9±9.2 years, time after onset: 87.1±48.2 months, ±SD). METHODS: In all patients, BoNTA was injected into spastic muscles of the affected upper limb (maximum total dose: 240 units). Four weeks later, they were hospitalized to receive 22 sessions of 20-min LF-rTMS and 120-min intensive OT daily over 15 days. Motor function of the affected upper limb was evaluated mainly using Fugl-Meyer Assessment (FMA), Wolf Motor Function Test (WMFT), motor activity log (MAL), and the severity of spasticity was measured with modified Ashworth scale (MAS) at BoNTA injection, discharge and four weeks post-discharge. RESULTS: All patients completed the protocol without any adverse effects. The FMA score and MAL scores, but not WMFT performance time, improved significantly at discharge. The MAS score of all examined muscles decreased significantly between BoNTA and discharge. The beneficial effect of the protocol on motor function and spasticity was almost maintained until four weeks after discharge. CONCLUSION: The protocol is safe and feasible, although further larger studies are needed to confirm its efficacy. CLINICAL REHABILITATION IMPACT: The protocol is a potentially useful neurorehabilitative approach for this patient population.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Espasticidade Muscular/reabilitação , Terapia Ocupacional/métodos , Paresia/reabilitação , Acidente Vascular Cerebral/complicações , Estimulação Magnética Transcraniana/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Toxinas Botulínicas Tipo A/administração & dosagem , Feminino , Seguimentos , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/etiologia , Fármacos Neuromusculares/administração & dosagem , Fármacos Neuromusculares/uso terapêutico , Paresia/etiologia , Estudos Retrospectivos , Reabilitação do Acidente Vascular Cerebral , Fatores de Tempo , Extremidade Superior
5.
J Pediatr Surg ; 36(12): 1781-4, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11733906

RESUMO

BACKGROUND/PURPOSE: Antiangiogenic agents offer a new approach to the treatment of aggressive neoplasms, yet very few agents are available for current use. The authors have shown previously the efficacy of antiangiogenic therapy in experimental Wilms tumor, using an investigative antibody. They hypothesized that topotecan, administered in a regimen targeting endothelial cells, would suppress tumor growth and angiogenesis in experimental Wilms tumor. METHODS: Experimental tumors were induced in the left kidneys of athymic mice by injection of cultured Wilms tumor cells. Topotecan (0.36, 0.6, 1.0, 2.0, and 3.0 mg/kg) or vehicle was injected intraperitoneally in 2 cycles over a 6-week period. Fluorescein angiograms and platelet endothelial cell adhesion molecule-1 staining of primary tumors were performed to ascertain vascular architecture. Endothelial apoptosis was assessed by TdT-mediated dUTP nick end labeling assay. RESULTS: Tumor weights were reduced significantly in treated versus control animals, even in the lowest-dose group. Endothelial cell staining and angiography results showed relatively sparse vascularity in treated xenografts. Endothelial apoptosis was observed in treated but not control tumors. CONCLUSIONS: Topotecan, delivered in an "antiangiogenic" regimen, even at very low doses, significantly inhibited growth of experimental Wilms tumors. No adverse effects were noted at low doses. Thus, the established chemotherapy agent topotecan may be useful in a novel role: as antiangiogenic therapy. J Pediatr Surg 36:1781-1784.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Topotecan/uso terapêutico , Tumor de Wilms/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Animais , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Camundongos , Camundongos Nus , Neovascularização Patológica/prevenção & controle , Topotecan/farmacologia , Tumor de Wilms/patologia
6.
J Pediatr Surg ; 36(8): 1177-81, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11479851

RESUMO

BACKGROUND/PURPOSE: Antibody to vascular endothelial growth factor (anti-VEGF) suppresses tumor growth and metastasis in experimental Wilms tumor. However, tumor growth accelerates if antibody is withdrawn. As recently shown, low-dose, frequently administered topotecan, a topoisomerase-1 inhibitor, has anti-angiogenic activity. The authors hypothesized that combined topotecan/anti-VEGF therapy would suppress tumor growth and metastasis more durably than either agent alone. METHODS: Xenografts were induced by intrarenal injection of human Wilms tumor cells in athymic mice (n = 59). Mice were divided into control (n = 10), anti-VEGF (n = 16), topotecan (n = 17), and topotecan plus anti-VEGF (n = 16) groups. All control and half the treated mice were killed at week 6. Remaining ("rebound") mice were maintained without treatment until week 8. Tumor vasculature was mapped by fluorescein angiography/PECAM immunostaining. Endothelial apoptosis was assessed by TUNEL assay. RESULTS: 6 weeks: Tumor weights were reduced significantly in treated mice (P <.003 v control). Seven of ten control and 1 of 25 treated mice displayed lung metastases (P <.003). Rebound tumors were largest in topotecan-only, intermediate in antibody-treated, and smallest in combination-treated mice. Immunostaining and angiography results showed sparse vascularity in treated xenografts. Endothelial apoptosis was observed only in treated tumors. CONCLUSION: Combination low-dose topotecan and anti-VEGF antibody therapy is antiangiogenic and suppresses tumor growth and metastasis in experimental Wilms tumor more durably than either agent alone.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neovascularização Patológica/prevenção & controle , Tumor de Wilms/tratamento farmacológico , Animais , Anticorpos Monoclonais/farmacologia , Biópsia por Agulha , Modelos Animais de Doenças , Fatores de Crescimento Endotelial/administração & dosagem , Fatores de Crescimento Endotelial/imunologia , Marcação In Situ das Extremidades Cortadas , Injeções Intraperitoneais , Neoplasias Renais/patologia , Linfocinas/administração & dosagem , Linfocinas/imunologia , Camundongos , Camundongos Nus , Transplante de Neoplasias , Valores de Referência , Sensibilidade e Especificidade , Taxa de Sobrevida , Topotecan/administração & dosagem , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Tumor de Wilms/patologia
7.
Clin Cancer Res ; 7(7): 1952-6, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11448909

RESUMO

A novel single-nucleotide polymorphism (SNP), 829C-->T in the 3'-untranslated region of the human dihydrofolate reductase (DHFR) gene transcript, was identified in the study population of 37 patients with childhood leukemias/lymphomas and 83 healthy Japanese children. Frequencies of the DHFR 829C/C, 829C/T, and 829T/T genotypes were 83.8, 10.8, and 5.4%, respectively, in the cases and 74.7, 19.3, and 6.0% in the controls, showing no significant difference in genotype frequencies between the cases and controls. When determined by real-time quantitative reverse transcription-PCR analysis, the highest expression of the DHFR transcript was demonstrated in the samples with a DHFR 829T/T polymorphism (P < 0.001). Direct association of the presence of the SNP with methotrexate-related adverse events in each patient was not demonstrated in this limited analysis. These data suggest that the novel DHFR 829 polymorphism is associated with a positive role in gene expression and provide evidence of a functional SNP in the 3' regulatory region of the gene.


Assuntos
Regiões 3' não Traduzidas/genética , Leucemia Mieloide Aguda/genética , Polimorfismo de Nucleotídeo Único , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Tetra-Hidrofolato Desidrogenase/genética , Adolescente , Sequência de Bases , Criança , Pré-Escolar , Análise Mutacional de DNA , DNA Complementar/química , DNA Complementar/genética , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Lactente , Leucemia Mieloide Aguda/enzimologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
8.
Brain Res Gene Expr Patterns ; 1(1): 17-21, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15018814

RESUMO

To study the change of gene expression in the brain tissues of schizophrenia, we used the gene expression monitoring technology and compared two sets of pools each containing four RNA samples of frontal cortex that were randomly selected from the control or schizophrenia group. We found that the expression of two genes were commonly altered in four pairwise comparisons; the expression of DEAD-box protein p72 (p72) gene was increased and neuropeptide Y (NPY) gene expression was decreased in the schizophrenia group compared with the control group. To substantiate these results, we estimated their mRNA levels by the real time TaqMan method in the 15 samples of each frontal or temporal cortex of four matched groups of schizophrenia, bipolar disorder, major depression and normal controls. A statistically significant decrease was observed for NPY in the frontal, but not in the temporal cortex, in the schizophrenia group (P=0.003). A decrease was also observed in the frontal cortex of the bipolar disorder group (P=0.031). In contrast, p72 gene expression showed no significant difference among the four groups. In conclusion, by novel technology of DNA array and TaqMan PCR analyses, we found that neuropeptide Y mRNA levels were significantly reduced in the frontal cortex in both schizophrenia and bipolar disorder.

9.
Clin Transpl ; : 195-201, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12211783

RESUMO

The living-donor liver transplant program at Kyoto University Hospital entered its 12th year in 2001. The rapid increase in adult patients that occurred with active use of right hemi-liver grafts is now reaching its plateau, limited by OR facilities and bed capacity. Graft selection is now being polarized to the left lateral section and right hemi-liver, and disease indications are becoming more similar to those for Western cadaveric programs, including a program for hepatocellular carcinoma. With the active introduction of right hemi-liver grafts, donor selection requires more multifactorial attention. Although most anatomical variants are managed surgically without significant risk, small-for-size grafts combined with high-risk patients are often a continuing problem even with the use of right hemi-liver grafts. Solutions for small-for-size syndrome with or without persistent portal hypertension and massive ascites are urgent targets of research. It will take some more time in Japan until the final establishment of a mutual compensatory system between cadaveric and living donor programs covering medical and socioeconomical aspects is achieved.


Assuntos
Transplante de Fígado , Doadores Vivos , Adolescente , Adulto , Idoso , Carcinoma Hepatocelular/cirurgia , Criança , Pré-Escolar , Hepatite B , Hepatite C , Humanos , Lactente , Recém-Nascido , Japão , Cirrose Hepática/cirurgia , Cirrose Hepática/virologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/métodos , Pessoa de Meia-Idade , Reoperação , Doadores de Tecidos , Resultado do Tratamento
10.
Biochem Biophys Res Commun ; 264(3): 768-73, 1999 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-10544006

RESUMO

Granzymes are a family of serine proteases exclusively detected in the granules of cytotoxic lymphocytes, and in mice at least eight granzymes, A to G and K, have been identified. Except for granzymes A and B, which activate the apoptotic pathway, little is known about the exact functions of the other granzymes. We have found that the granzyme D transcript is selectively expressed in functional hematopoietic stromal lines as well as primary stromal cells. Stromal lines supported growth of a pre-T lymphoma clone BTK at an efficiency proportional to the expression level of granzyme D, while a stromal line lacking granzyme D failed to do so. When the defective stromal line was transfected with granzyme D cDNA, it could efficiently support the growth of BTK cells. The results indicate that granzyme D expressed in the stromal cells plays an important role in stromal cell-lymphocyte interaction.


Assuntos
Hematopoese , Serina Endopeptidases/fisiologia , Células Estromais/fisiologia , Animais , DNA Complementar/genética , Regulação da Expressão Gênica/fisiologia , Granzimas , Camundongos , Camundongos Endogâmicos BALB C
11.
Gene ; 227(1): 39-47, 1999 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-9931425

RESUMO

A mouse homologue of the human Rep-8 gene was cloned by PCR methods using degenerate oligonucleotide primers corresponding to highly conserved regions between human and mouse genes, and by the Marathon-Ready cDNA amplification method. The full-length mouse Rep-8 contains 1422 nucleotides and codes for a protein of 277 amino acids with a calculated mol. wt. of 31,519. The overall amino acid sequence homology between mouse and human Rep-8 proteins was 73%, and the overall nucleic acid sequence similarity was 65%. The predicted amino acid sequence of mouse Rep-8 has leucine zipper-like motifs in the N-terminal region, similar to the human Rep-8 protein. Rep-8 exists as a single-copy gene and is expressed in both the early and late embryonic stages of mouse development, suggesting that the Rep-8 gene product has an important role in embryogenesis. The genomic structure of the mouse Rep-8 gene was characterized extensively so that a gene targeting strategy could be used to develop an understanding of the biological function(s) of this interesting gene and its product.


Assuntos
Proteínas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar , Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Dados de Sequência Molecular , Técnicas de Amplificação de Ácido Nucleico , Regiões Promotoras Genéticas , Conformação Proteica , Distribuição Tecidual
13.
Genomics ; 46(1): 138-42, 1997 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9403069

RESUMO

We previously identified eight testis-specific genes using antibodies raised against testicular germ cells. They are expressed during spermatogenesis and are presumed to be involved in testicular germ cell differentiation and sperm formation. We have mapped the genomic loci for these testis-specific genes using restriction fragment length variants in interspecific backcross mice. The calmegin gene (Clgn) was mapped to Chr 8. The synaptonemal complex protein gene 1 (Sycp1) probe hybridized with two sequences on different chromosomes; Sycp1-rs2 was mapped to Chr 3, whereas Sycp1-rs3 was mapped to Chr 7. The relaxin-like factor gene (Rlnl) was mapped to Chr 8, and collapsin response mediator protein 1 (Crmp1) was mapped to Chr 5. Three novel genes encoding testis-specific proteins A2 (Tsga2), A8 (Tsga8), and A12 (Tsga12) were mapped to chromosomes 3, X, and 10, respectively.


Assuntos
Calnexina , Mapeamento Cromossômico , Genes/genética , Espermatogênese/genética , Testículo/fisiologia , Animais , Proteínas de Ligação ao Cálcio/genética , Cruzamentos Genéticos , Proteínas de Ligação a DNA , Insulina , Masculino , Camundongos , Camundongos Endogâmicos C3H , Chaperonas Moleculares , Dados de Sequência Molecular , Muridae , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Fosfoproteínas/genética , Polimorfismo de Fragmento de Restrição , Proteínas/genética
14.
Anat Anz ; 173(4): 193-8, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1803943

RESUMO

The petropharyngeal muscles were observed in 7 cadavers, 8 cases (1.4%) [both side: one case (0.3%), one side: 6 cases (1.9%)] in 614 Japanese cadavers. All cases of this supernumerary muscles of the stylopharyngeal muscle took origin from the petrous part of the temporal bone to inserted to the outer surface of the middle constrictor pharyngeal muscles. And also of its muscle bundles were innervated by the glossopharyngeal nerve and supplied from the ascending pharyngeal artery. The appearance of the sex differences male was much higher than female in Japanese.


Assuntos
Povo Asiático , Músculos/anatomia & histologia , Faringe/anatomia & histologia , Idoso , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais
15.
Okajimas Folia Anat Jpn ; 66(6): 375-91, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1692402

RESUMO

The filiform papillae of subadult alligator (120 cm-260 cm total length) tongues are examined by scanning electron microscopy and electron microprobe analysis. The filiform papillae form cone-like structures and are observed over the entire dorsal surface of a relatively long tongue with a round tip. The filiform papillae are composed of four layers; outer, upper intermediate, lower intermediate, and basal layer. The keratinized epithelial cells are analysed by the sulphur (S), and nitrogen (N) content levels. The S content is higher than that of N. In the anterior side of the filiform papillae, this content is lower than that in the posteriors. The S content is highest of all at about 2 microns in depth from the surface. These results suggest that the use of S concentration measurements may serve to be an effective tool for a simple, offhand evaluation of keratinization.


Assuntos
Jacarés e Crocodilos/anatomia & histologia , Répteis/anatomia & histologia , Língua/anatomia & histologia , Jacarés e Crocodilos/metabolismo , Animais , Epitélio/análise , Epitélio/anatomia & histologia , Queratinas/análise , Microscopia Eletrônica , Nitrogênio/análise , Enxofre/análise , Língua/análise
16.
Surg Radiol Anat ; 12(1): 69-71, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2345900

RESUMO

A supernumerary cusp of the valve of the pulmonary trunk was found in a 75-year old, male Japanese. The valve was composed of 4 cusps of different size and shape. The supernumerary cusp was located between the right and left cusps. We found this case from a series of 1,100 consecutive necropsies.


Assuntos
Valva Pulmonar/anormalidades , Idoso , Humanos , Masculino , Valva Pulmonar/patologia
17.
J Morphol ; 205(2): 165-172, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29865754

RESUMO

Functional teeth from young American alligators (120 cm to 260 cm total length) were prepared for scanning electron microscopy (SEM) and electron microprobe analysis (EPMA) of the elements of the enamel layer. On the tip of the tooth, the enamel layer is thick, but over the crown it gradually reduces in thickness until it disappears near the cement-enamel junction. The enamel layer is distinguished by inner and outer layers. The inner layer is formed of separated, irregularly shaped blocks composed of small crystals. In the outer layer, the enamel crystals are closely packed and oriented perpendicularly to the surface. Radially oriented, lamella-like structures of the enamel are elongated, crystallized bands which extend from the inner to the outer layer of the enamel as reported by Kvam (Acta Odontol. Scand. 17:745-751, 1959). The highest density of crystals occurs in the enamel layer before complete calcification. Concentrations of iron, copper, and fluoride are located approximately 20 µm below the surface of the enamel in the outer layer where crystals are closely packed. The concentration of trace elements (e.g., Fe, F, Cu) is related to the formation of hydroxyapatite.

18.
Biochem Pharmacol ; 38(24): 4405-13, 1989 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-2604743

RESUMO

Male Sprague-Dawley rat liver cytosol mediated regioselective conjugation of styrene 7,8-oxide (STO) enantiomers with glutathione in completely trans-ring-opening manner to afford (1S)-S-(1-phenyl-2-hydroxyethyl)glutathione and (2R)-S-(2-phenyl-2-hydroxyethyl)glutathione in the ratio 22:1 for (R)-STO and also to afford (1R)-S-(1-phenyl-2-hydroxyethyl)glutathione and (2S)-S-(2-phenyl-2-hydroxyethyl)glutathione in the ratio 12:1 for (S)-STO. In the above cytosolic reactions, (R)-STO was conjugated 1.8 times faster than (S)-STO, while the (R)- to (S)-ratio in rate of the conjugation was 2.7 when racemic STO was used as a substrate. A kinetic study, carried out by using six major glutathione transferase (GST) isoenzymes isolated from the cytosol, indicated that GSTs 3-3, 3-4 and 4-4 (class mu enzymes) had much higher Kcat/Km values towards both STO enantiomers than the other three major isoenzymes, GSTs 1-1, 1-2 and 2-2 (class alpha enzymes). All the class mu enzymes mediated preferential glutathione conjugation of (R)-STO to (S)-STO. On the contrary, the class alpha enzymes catalysed the conjugation of (S)-STO preferentially to (R)-STO. The kinetic study strongly suggested that GSTs determining the higher enantioselectivity towards (R)-STO in the rat liver cytosol were the class mu enzymes, especially GST 3-3, which had the highest Kcat/Km value towards (R)-STO as well as the highest (R) to (S) ratio in the enantioselectivity among the six isoenzymes examined. GST 7-7, isolated as a major enzyme from the liver cytosol of the animals bearing hepatic hyperplastic nodules which were induced by chemical carcinogens, catalysed preferential GSH conjugation of (S)-STO to (R)-STO.


Assuntos
Compostos de Epóxi/metabolismo , Éteres Cíclicos/metabolismo , Glutationa Transferase/metabolismo , Glutationa/metabolismo , Isoenzimas/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Compostos de Epóxi/análise , Compostos de Epóxi/antagonistas & inibidores , Glutationa Transferase/análise , Isomerismo , Fígado/enzimologia , Masculino , Ratos , Ratos Endogâmicos
19.
Biochem Pharmacol ; 38(16): 2609-13, 1989 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-2764984

RESUMO

The fluorophotometric substrate, 7-glycidoxycoumarin (GOC), was examined for the assay of epoxide-glutathione (GSH)-conjugating activities of seven major GSH transferases (GSTs) isolated from rat liver cytosols. GST 7-7 (GST-P), isolated from the liver cytosol of rats bearing hepatic hyperplastic nodules, catalysed the GSH conjugation of GOC at a higher rate than any other examined GST isolated from the normal rat liver cytosol. GSTs 3-3, 3-4 and 4-4 (group 3-4 enzymes) had specific activities towards GOC by one fifth to one third of that of GST 7-7. GSTs 1-1, 1-2 and 2-2 (group 1-2 enzymes) had very low activities towards this epoxide. A kinetic study indicated that GST 7-7 showed the largest kappa cat/Km value for the catalytic reaction of GOC-GSH conjugation among the GSTs. In spite of their much smaller kappa cat values, group 3-4 enzymes showed much larger kappa cat/Km values for GOC than the group 1-2 enzymes, because GOC had a much higher affinity for group 3-4 enzymes than for group 1-2 enzymes. A comparative study was also done with GSH conjugations of styrene 7,8-oxide (STO) and 1-chloro-2,4-dinitrobenzene by the GSTs. Unlike GOC, the conjugation of STO was mediated at rates about twice as high by group 3-4 enzymes than by GST 7-7. STO was also a very poor substrate for group 1-2 enzymes.


Assuntos
Cumarínicos/metabolismo , Glutationa Transferase/fisiologia , Glutationa/metabolismo , Fígado/enzimologia , Animais , Dinitroclorobenzeno/metabolismo , Compostos de Epóxi/metabolismo , Técnicas In Vitro , Isoenzimas/fisiologia , Masculino , Ratos , Ratos Endogâmicos , Especificidade por Substrato
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