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2.
Br J Cancer ; 101(9): 1537-42, 2009 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-19862000

RESUMO

BACKGROUND: Neutropenia is a common adverse reaction of chemotherapy. We assessed whether chemotherapy-induced neutropenia could be a predictor of survival for patients with non-small-cell lung cancer (NSCLC). METHODS: A total of 387 chemotherapy-naïve patients who received chemotherapy (vinorelbine and gemcitabine followed by docetaxel, or paclitaxel and carboplatin) in a randomised controlled trial were evaluated. The proportional-hazards regression model was used to examine the effects of chemotherapy-induced neutropenia and tumour response on overall survival. Landmark analysis was used to lessen the bias of more severe neutropenia resulting from more treatment cycles allowed by longer survival, whereby patients who died within 126 days of starting chemotherapy were excluded. RESULTS: The adjusted hazard ratios for patients with grade-1 to 2 neutropenia or grade-3 to 4 neutropenia compared with no neutropenia were 0.59 (95% confidence interval (CI), 0.36-0.97) and 0.71 (95% CI, 0.49-1.03), respectively. The hazard ratios did not differ significantly between the patients who developed neutropenia with stable disease (SD), and those who lacked neutropenia with partial response (PR). CONCLUSION: Chemotherapy-induced neutropenia is a predictor of better survival for patients with advanced NSCLC. Prospective randomised trials of early-dose increases guided by chemotherapy-induced toxicities are warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neutropenia/induzido quimicamente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Incidência , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Neutropenia/epidemiologia , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Biochim Biophys Acta ; 1438(2): 204-12, 1999 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-10320803

RESUMO

The increased production of oxygen-derived free radicals (OFR) and lipid peroxidation may contribute to vascular complications in diabetes. Some lipid peroxidation products have already been reported to be formed via glucose-induced oxidative stress. We have identified 9-hydroxy linoleic acid (9-OH-C18:2) in the red cell membrane phospholipid of diabetic subjects. We hypothesized that 9-OH-C18:2 would be formed in hydroxyl radical reactions to linoleic acid (C18:2) during glucose-induced oxidative stress, and confirmed that the formation of 9-OH-C18:2 was induced by ultraviolet (UV)-C irradiation to the synthetic C18:2. UV-C light generates highly reactive hydroxy radicals. C18:2 is confirmed to be the precursor of 9-OH-C18:2. To estimate the degree of oxidative damage to red cell membrane phospholipids, we developed a selective ion monitoring gas chromatography-mass spectrometric measurement for C18:2 and 9-OH-C18:2, following methanolysis of red cell membrane phospholipids. The relative peak height ratio of C18:2 to 9-OH-C18:2 (9-OH-C18:2/C18:2) was measured in phospholipid extracts of red cell membranes from healthy (n=29, 3.1+/-1.9%) and diabetic (n=27, 20. 9+/-16.1%) subjects. It was confirmed that 9-OH-C18:2/C18:2 is significantly (P<0.001) elevated in patients with diabetes. The measurement of 9-OH-C18:2/C18:2 in red cell membranes should be useful for assessing oxidative damage to membrane phospholipids in diabetes.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Membrana Eritrocítica/metabolismo , Ácidos Linoleicos Conjugados , Ácidos Linoleicos/biossíntese , Biomarcadores/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Oxirredução , Fosfolipídeos/metabolismo
4.
Biochim Biophys Acta ; 1492(2-3): 369-76, 2000 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-11004509

RESUMO

In Saccharomyces cerevisiae, phosphoacetylglucosamine mutase is encoded by an essential gene called AGM1. The human AGM1 cDNA (HsAGM1) and the Candida albicans AGM1 gene (CaAGM1) were functionally cloned and characterized by using an S. cerevisiae strain in which the endogenous phosphoacetylglucosamine mutase was depleted. When expressed in Escherichia coli as fusion proteins with glutathione S-transferase, both HsAgm1 and CaAgm1 proteins displayed phosphoacetylglucosamine mutase activities, demonstrating that they indeed specify phosphoacetylglucosamine mutase. Sequence comparison of HsAgm1p with several hexose-phosphate mutases yielded three domains that are highly conserved among phosphoacetylglucosamine mutases and phosphoglucomutases of divergent organisms. Mutations of the conserved amino acids found in these domains, which were designated region I, II, and III, respectively, demonstrated that alanine substitutions for Ser(64) and His(65) in region I, and for Asp(276), Asp(278), and Arg(281) in region II of HsAgm1p severely diminished the enzyme activity and the ability to rescue the S. cerevisiae agm1Delta null mutant. Conservative mutations of His(65) and Asp(276) restored detectable activities, whereas those of Ser(64), Asp(278), and Arg(281) did not. These results indicate that Ser(64), Asp(278), and Arg(281) of HsAgm1p are residues essential for the catalysis. Because Ser(64) corresponds to the phosphorylating serine in the E. coli phosphoglucosamine mutase, it is likely that the activation of HsAgm1p also requires phosphorylation on Ser(64). Furthermore, alanine substitution for Arg(496) in region III significantly increased the K(m) value for N-acetylglucosamine-6-phosphate, demonstrating that Arg(496) serves as a binding site for N-acetylglucosamine-6-phosphate.


Assuntos
Fosfotransferases (Fosfomutases)/genética , Fosfotransferases (Fosfomutases)/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Sítios de Ligação , Candida albicans/enzimologia , Candida albicans/genética , Catálise , Clonagem Molecular , Análise Mutacional de DNA , DNA Complementar/análise , Biblioteca Genômica , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Homologia de Sequência de Aminoácidos
5.
FEBS Lett ; 435(1): 49-54, 1998 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-9755857

RESUMO

The amino acid sequence of the Saccharomyces cerevisiae mRNA 5'-triphosphatase (TPase) diverges from those of higher eukaryotes. In order to confirm the sequence divergence of TPases in lower and higher eukaryotes, the Candida albicans gene for TPase was identified and characterized. This gene designated CaCET1 (C. albicans mRNA 5'-capping enzyme triphosphatase 1) has an open reading frame of 1.5 kb, which can encode a 59-kDa protein. Although the N-terminal one-fifth of S. cerevisiae TPase (ScCet1p) is missing in CaCet1p, CaCet1p shares significant sequence similarity with ScCet1p over the entire region of the protein; the recombinant CaCet1p, which was expressed as a fusion protein with glutathione S-transferase (GST), displayed TPase activity in vitro. CaCET1 rescued CET1-deficient S. cerevisiae cells when expressed under the control of the ADH1 promoter, whereas the human capping enzyme derivatives that are active for TPase activity but defective in mRNA 5'-guanylyltransferase (GTase) activity did not. Yeast two-hybrid analysis revealed that C. albicans Cet1p can bind to the S. cerevisiae GTase in addition to its own partner, the C. albicans GTase. In contrast, neither the full-length human capping enzyme nor its TPase domain interacted with the yeast GTase. These results indicate that the failure of the human TPase activity to complement an S. cerevisiae cet1delta null mutation is attributable, at least in part, to the inability of the human capping enzyme to associate with the yeast GTase, and that the physical association of GTase and TPase is essential for the function of the capping enzyme in vivo.


Assuntos
Hidrolases Anidrido Ácido/genética , Hidrolases Anidrido Ácido/isolamento & purificação , Candida albicans/enzimologia , Genes Fúngicos , Capuzes de RNA/metabolismo , Hidrolases Anidrido Ácido/metabolismo , Sequência de Aminoácidos , Candida albicans/genética , Clonagem Molecular , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Teste de Complementação Genética , Humanos , Dados de Sequência Molecular , Mutagênese , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Capuzes de RNA/genética , Saccharomyces cerevisiae/genética
6.
FEBS Lett ; 348(1): 27-32, 1994 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-8026578

RESUMO

HM-1 killer toxin secreted from Hansenula mrakii inhibits the growth of Saccharomyces cerevisiae cells by interfering with beta-1,3-glucan synthesis. We found that HM-1 killer toxin killed intact cells but not protoplasts. In addition, cells lacking the functional KRE6 allele (kre6 delta) became resistant to higher concentration of HM-1 killer toxin. As reported by Roemer and Bussey [(1991) Proc. Natl. Acad. Sci. 88 11295-11299], cells lacking functional KRE6 had a reduced level of the cell wall beta-1,6-glucan compared to that in cells harboring the normal KRE6. These results suggest that the cell wall beta-glucan is involved in the action of HM-1 killer toxin. Addition of HM-1 killer toxin with several kinds of oligosaccharides revealed that either beta-1,3- or beta-1,6-glucan blocked the cytocidal action of HM-1 killer toxin whereas alpha-1,4-glucan and chitin did not. Mannan also interfered with HM-1 killer toxin action, but this inhibitory effect was much weaker than that observed with beta-1,3- or beta-1,6-glucans. Thus, it appears that the cell wall beta-glucan interacts with HM-1 killer toxin, and that this toxin-beta-glucan commitment is required for the action of HM-1 killer toxin.


Assuntos
Glucanos , Micotoxinas/farmacologia , Pichia/fisiologia , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/efeitos dos fármacos , beta-Glucanas , Parede Celular/efeitos dos fármacos , Resistência Microbiana a Medicamentos , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiologia , Fatores Matadores de Levedura , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Mutação
7.
Atherosclerosis ; 148(1): 197-202, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10580186

RESUMO

Increased urinary excretion of dicarboxylic acids (DAs) has been well known in patients with diabetic ketoacidosis (DKA). It was known that small amounts of such DAs were also detected in urine from healthy humans. Upon chemical, radiation-induced or enzymatic oxidation, cis-polyunsaturated fatty acids (PUFA) have previously been shown to generate saturated short- and medium-chain length DAs. In diabetes, it was confirmed that the imbalance between the generation of free radicals and antioxidant defense systems increases oxidative stress and leads to the damage of lipid, which contains PUFA. Some peroxidation products of PUFA, such as malondialdehyde and conjugated diene, are generally known to be elevated in patients with diabetes. The present study was undertaken to determine if urinary excretion of DAs is elevated in diabetic patients without DKA. Urine samples from ten non-ketoacidotic patients with type 2 diabetes and ten healthy subjects were examined for DAs by combined gas chromatography and mass spectrometry with selected ion monitoring. The diabetic subjects had significantly (Psebacic acid. Being stable and easily detectable compounds, DAs may be considered potential markers of oxidative attack on PUFA in diabetes.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Ácidos Dicarboxílicos/urina , Ácidos Graxos/metabolismo , Peróxidos/metabolismo , Adulto , Idoso , Biomarcadores/urina , Diabetes Mellitus Tipo 2/urina , Estabilidade de Medicamentos , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Immunol Lett ; 62(3): 177-81, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9698117

RESUMO

The soluble form of the leukocyte membrane antigen CD14 is known to increase the sensitivity of endothelial and epithelial cell lines to bacterial lipopolysaccharide (LPS). This molecule also directly induces cytokine production in monocytes. Here, the effect of sCD14 and LPS on the release of IL-6 and IL-8 by human bronchial epithelial cells (HBECs) was studied. Soluble CD14 induced cytokine production both in the presence and absence of LPS. In addition, neither sCD14 nor anti-CD14 monoclonal antibody which blocks the interaction of LPS with CD14 had any effect on the binding of LPS to HBECs. These data suggest that sCD14 may induce the release of IL-6 and IL-8 from HBECs. However, the binding of LPS to bronchial epithelium appears to be mediated by CD14-independent mechanisms.


Assuntos
Brônquios/imunologia , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Brônquios/citologia , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , Fluoresceína-5-Isotiocianato , Humanos , Receptores de Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/farmacologia , Mitógenos/farmacologia
9.
Immunol Lett ; 70(2): 83-8, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10569696

RESUMO

The multifunctional cytokine IL-6, which can be locally produced by human bronchial epithelial cells (HBECs), has been found to play a role in IL-4 dependent IgE synthesis. Since the allergic reaction in bronchial asthma is associated with the upregulation of IL-4 and Th2 type of immune response, the purpose of our study was to assess whether IL-4 and related cytokines IL-10 and IL-13 regulate IL-6 release by HBEC s. HBECs were obtained by bronchial brushing, cultured in LHC-9/RPMI 1640. At the third passage the cells were stimulated with cytokines (0.1-20 ng/ml) diluted in unsupplemented media for 24 h. The supernatants were tested for IL-6 content by sandwich ELISA. Unstimulated HBECs produced detectable amounts of IL-6 (368+/-25 pg/ml). Exposure to IL-10 (368+/-22 pg/ml) and IL-13 (395+/-6 pg/ml) resulted in little changes. IL-4 caused a slight but significant increase in IL-6 release (530+/-45 pg/ml), P<0.05, TNFalpha (1657+/-85 pg/ml) and IFNgamma (1953+/-37 pg/ml) showed strong induction of IL-6 release in HBECs (P<0.005 and P<0.001, respectively). Both IL-4 and IL-13 significantly inhibited TNF induced IL-6 release (P<0.01 for both) while augmenting the effect of IFNgamma (P<0.005 and P<0.01, respectively.). IL-10 was without a significant effect. We conclude that Th2-type cytokines IL-4 and IL-13 affect the release of IL-6 by HBECs in response to TNFalpha (inhibition) and IFgamma (augmentation). IL-10 had no effect on the regulation of IL-6 release. Modulation of IL-6 levels by Th2-type cytokines may play a role in allergic reactions through the IL-6 promoting effect on IL-4 mediated IgE production.


Assuntos
Brônquios/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Interleucina-13/farmacologia , Interleucina-4/farmacologia , Interleucina-6/biossíntese , Células Th2/imunologia , Brônquios/metabolismo , Células Cultivadas , Meios de Cultura Livres de Soro , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/metabolismo , Humanos
10.
Environ Health Perspect ; 59: 129-35, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3921355

RESUMO

Mercapto-, methylthio-, methylsulfinyl- and methysulfonyl metabolites of PCBs 2,5,2',5'-tetrachlorobiphenyl, 1,3,5-trichlorobenzene and some other chlorobenzenes were identified in adipose tissues of mice, rats and guinea pigs by using GC/MS/COM systems. By means of administration of CD3-methionine, it was confirmed that the methyl group in methylthio metabolites was derived from the methionine. Moreover, after pretreatment with either esterification of urinary metabolites in guinea pigs with 1,3,5-trichlorobenzene and 1,3-dichlorobenzene or N-acetylation after esterification, it was confirmed that cysteinylglycine, cysteine, N-acetylcysteine, cysteamine, mercaptopyruvate, mercaptolactate, mercaptacetate, thiol and disulfide conjugates were detected as a serial modified derivatives of glutathione moiety. These results are summarized as a metabolic proposed pathway of halogenated aromatic compounds. Three routes in pathway correspond to oxygenation (initial route), glutathione thioether disposition (intermediate route) and sulfoxydation (final route) in connection with both reactive intermediates of epoxide and thiol. Methylation of the thiol by S-adenosylmethionine may be important in inhibiting covalent binding of reactive intermediates with biocomponents, similar to the glutathione conjugation for the detoxification of epoxide.


Assuntos
Carcinógenos , Hidrocarbonetos Halogenados/metabolismo , Sulfonas/biossíntese , Animais , Biotransformação , Fenômenos Químicos , Química , Cisteína/metabolismo , Dimetil Sulfóxido , Fígado/metabolismo , Metionina/metabolismo , Camundongos , Bifenilos Policlorados/metabolismo , Ratos , Sulfonas/metabolismo
11.
Chest ; 102(3): 832-7, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1516411

RESUMO

We compared the doubling time of fibroblasts derived from idiopathic pulmonary fibrosis (usual interstitial pneumonia) (IPF [UIP]) lung tissues and control fibroblasts, cultured in usual growth medium, and examined the response of these fibroblasts to platelet-derived growth factor (PDGF) and prostaglandin E2 (PGE2). Ten fibroblast lines from open lung biopsy specimens of patients with IPF (UIP) and ten control fibroblast lines from surgically resected lung tissue of patients with limited lung diseases were established. The average doubling time of fibroblast lines was 32.0 +/- 6.0 h (mean +/- SD) in UIP and 33.2 +/- 10.4 h in controls, showing no difference between the two groups. To examine the responses of fibroblasts to PDGF and PGE2 and the differences between fibroblasts derived from fibrotic tissues with different intensity of fibrosis, lung specimens from five patients with IPF were subdivided into two groups, higher-intensity fibrotic lesions (H) and lower-intensity fibrotic lesions (L). The fibroblast lines were established separately. 3H-thymidine uptake with or without PDGF or PGE2 was examined. Results were expressed as the index of thymidine incorporation into the fibroblasts. There were no differences in the doubling times and the responses to PDGF and PGE2 between H and L. There were no differences between control and H regarding their response to PDGF. In response to PGE2, the growth inhibition for H was significantly decreased compared with the control (p less than 0.05). There was no difference in growth inhibition between H and L. The finding that PGE2 inhibits fibroblast proliferation less in UIP lung tissue suggests that fibroblasts from UIP were functionally altered cells or, to some extent, out of normal regulation. These results suggest an abnormal proliferation of fibroblasts observed in IPF (UIP).


Assuntos
Dinoprostona/farmacologia , Fibroblastos/citologia , Pulmão/patologia , Fator de Crescimento Derivado de Plaquetas/farmacologia , Fibrose Pulmonar/patologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Timidina/metabolismo , Fatores de Tempo , Trítio
12.
Metabolism ; 48(2): 205-9, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10024083

RESUMO

In diabetes, glycation and subsequent browning (or glycoxidation) reactions are enhanced by elevated glucose concentrations. It is unclear whether the diabetic state per se also induces an increase in the generation of oxygen-derived free radicals (OFRs). However, there is some evidence that glycation itself may induce the formation of OFRs. OFRs cause oxidative damage to endogenous molecules, including cholesterol. 7-Oxocholesterol is known to be one of the major products of cholesterol oxidation. The level of cholesterol peroxidation products was assessed in erythrocyte membrane lipid by monitoring the peak height ratio of 7-oxocholesterol, one of the products of cholesterol peroxidation, to cholesterol with gas chromatography/mass spectrometry (GC/MS). The peak height ratio of 7-oxocholesterol to cholesterol was used as a biomarker of lipid peroxidation. The hemoglobin A1c (HbA1c) value, an index of glycemic stress, was measured by high-performance liquid chromatography. We examined the relationship between the levels of cholesterol peroxidation products and HbA1c in erythrocytes of diabetic and healthy subjects. There was a significantly increased ratio of 7-oxocholesterol to cholesterol in diabetic erythrocytes compared with control erythrocytes. The ratio of 7-oxocholesterol to cholesterol was significantly correlated with the level of HbA1c. This suggests that glycation of hemoglobin via chronic hyperglycemia is linked to cholesterol peroxidation in erythrocytes of both diabetic and healthy subjects.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Eritrócitos/metabolismo , Hemoglobinas Glicadas/metabolismo , Peroxidação de Lipídeos , Colesterol/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Cetocolesteróis/sangue , Masculino , Pessoa de Meia-Idade
13.
Clin Biochem ; 33(7): 541-7, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11124339

RESUMO

OBJECTIVES: To reveal increased lipid peroxidation in diabetics by quantification of cholesterol oxidation products (COPs) not only in plasma, but also in erythrocytes. DESIGN AND METHODS: We quantified 7-ketocholesterol (7-kCho) by gas chromatography-mass spectrometry as a surrogate measure for COPs. These assays were performed on both plasma and erythrocytes in 20 control subjects and 20 treated patients with relatively poorly controlled Type 2 diabetes. RESULTS: Both plasma and erythrocyte 7-kCho levels in diabetics were significantly higher than those in control subjects. Although neither plasma nor erythrocyte 7-kCho levels were associated with markers for glucose tolerance in diabetics, a negative correlation of serum HDL-cholesterol levels with erythrocyte, but not plasma, 7-kCho levels was found. CONCLUSION: Increased oxidative stress in diabetics affects oxidation of cholesterol. Assays of COPs not only in plasma, but also in erythrocytes, may yield complementary information in lipid peroxidation.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Eritrócitos/metabolismo , Cetocolesteróis/sangue , Estresse Oxidativo , Plasma/metabolismo , Idoso , Calibragem , Estudos de Casos e Controles , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio/metabolismo , Fatores de Risco , Fatores Sexuais , Fatores de Tempo
14.
Neurosci Lett ; 158(1): 63-6, 1993 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-8233074

RESUMO

To investigate the effect of toluene and its derivatives on neural activity, postsynaptic field potential (population spike, PS) of granule cells as well as antidromic potential (AP) and presynaptic fiber potential (FP) (perforant path) were recorded in the guinea pig hippocampal slices. Toluene at the concentration of 0.2 ng/ml to 20 micrograms/ml in the perfusion medium increased the amplitude of PS to 109-150%. Toluene also increased the amplitude of FP and AP, although the most remarkable enhancement was observed in the PS. However, toluene at the concentrations over 1000 micrograms/ml completely depressed the PS, whereas it increased the amplitude of AP to 130% of the original level. These results indicate that toluene has excitatory and inhibitory biphasic effects on neurotransmission in the hippocampal slices according to concentration applied.


Assuntos
Hipocampo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Tolueno/farmacologia , Animais , Potenciais Evocados/efeitos dos fármacos , Cobaias , Hipocampo/citologia , Técnicas In Vitro , Fibras Nervosas/efeitos dos fármacos , Perfusão , Transmissão Sináptica/efeitos dos fármacos
15.
Clin Chim Acta ; 170(2-3): 305-14, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3436064

RESUMO

A new method for extraction and quantification of plasma o,p'-DDD (2,2-(2-chlorophenyl,4'-chlorophenyl)1,1-dichloroethane) and its metabolites has been developed. When plasma (0.1 ml) adsorbed to and dried on a filter paper was heated with 5% hydrogen chloride in methanol (1 ml) in a boiling water bath, o,p'-DDD and its metabolites were liberated from the serum protein and were able to be easily extracted with benzene. The recovery rate was raised compared with conventional methods. In addition, this procedure also carried out the simultaneous methylation of o,p'-DDA, one of the metabolites. Mass numbers of 199, 210, 235 and 246 were selected from the mass spectra of o,p'-DDD and its related substances, and they were monitored. Identification was performed on the basis of the retention time and the mass peak intensity ratio. Quantitative determination was performed using the internal standard technique. It was learned that o,p'-DDA is present in the plasma at a concentration about 10 times higher than the levels of o,p'-DDD and o,p'-DDE.


Assuntos
Mitotano/análogos & derivados , Mitotano/sangue , Ritmo Circadiano , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos
16.
Clin Chim Acta ; 252(2): 137-45, 1996 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-8853561

RESUMO

Lipids in erythrocyte membranes from 16 hemodialysis patients and 16 healthy volunteers were studied using gas chromatographic mass spectrometry. 7-keto cholestadiene was first reported in this study. The ratios of 7-keto cholestadiene to cholesterol, the ratios of arachidonate to cholesterol and the ratios of dochosahexanate to cholesterol in peak heights of chromatograms were measured in both groups as the markers of lipid peroxidation. Higher 7-keto cholestadiene/cholesterol ratios and lower arachidonate/cholesterol and dochosahexanate/cholesterol ratios were significantly observed in hemodialysis patients compared with healthy subjects. Our results are evidence that hemodialysis patients are exposed to much oxidative stress. It has been suggested that, during hemodialysis, leukocytes are activated by contract with non-physiological surfaces of the blood line tubing and produce oxygen free radicals. Oxygen free radicals attach cholesterol, arachidonate and dochosahexanate to produce lipid peroxides. In this study, this cell activation may be responsible for the increased lipid peroxidation of hemodialysis patients, 7-Keto cholestadiene, arachidonate and dochosahexanate can be used as markers of lipid peroxidation in hemodialysis patients.


Assuntos
Membrana Eritrocítica/metabolismo , Falência Renal Crônica/sangue , Lipídeos de Membrana/sangue , Adulto , Idoso , Biomarcadores , Ácidos Graxos Insaturados/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Falência Renal Crônica/terapia , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Terapia de Substituição Renal
17.
Clin Chim Acta ; 285(1-2): 35-44, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10481921

RESUMO

Oxidative stress is postulated to be increased in patients with diabetes mellitus. Glycation enhanced by elevated glucose concentrations may induce the formation of oxygen-derived free radicals (OFRs). OFRs would cause oxidative damage to endogenous molecules, including cholesterol. Accumulating evidence suggests that oxidative cell injury caused by OFRs contributes to the development of both macroangiopathy and microangiopathy in diabetes. Our previous studies have shown that 7-keto cholestadien is one of the major products of cholesterol peroxidation in diabetic erythrocyte membrane and its levels correlate with hemoglobin Alc (HbAlc) values. We have newly identified 3-cholesten-6-one, one of the minor products of cholesterol peroxidation, in it. The aim of our study is to investigate whether 3-cholesten-6-one levels also correlate with HbAlc values. Levels of 3-cholesten-6-one were assessed in erythrocyte membrane lipid by monitoring peak areas of 3-cholesten-6-one to cholesterol with gas chromatography-mass spectrometry. The peak area ratio of 3-cholesten-6-one to cholesterol was used as a marker of cholesterol peroxidation. The HbAlc value, an index of both glycemic stress and glycation, was measured by high-performance liquid chromatography. In this study, we evaluated 33 diabetic and 29 healthy subjects, matched for age (59.3+/-14.5 vs. 57.3+/-13.7 years, mean+/-S.D.) and sex (15 males and 14 females vs. 16 males and 17 females). There were both significantly raised HbAlc levels (4.6+/-0.8 vs. 8.3+/-2.4%, P<0.001) and significantly increased ratios of 3-cholesten-6-one to cholesterol (0.2+/-0.4 vs. 21+/-1.8, P<0.001) in diabetic patients compared to control subjects. A good correlation between HbAlc levels and ratios of 3-cholesten-6-one to cholesterol was found in participants (r = 0.75, P<0.001, y = 0.46x-1.8). This suggests that an oxidative stress exists in diabetes and the link between glycation and lipoxidation is found in diabetic red blood cell.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Eritrócitos/metabolismo , Hemoglobinas Glicadas/metabolismo , Lipídeos/sangue , Estresse Oxidativo , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade
18.
Clin Chim Acta ; 276(2): 163-72, 1998 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-9764734

RESUMO

In diabetes, the glycation and subsequent browning (or glycoxidation) reactions are enhanced by elevated glucose concentrations. It is unclear whether or not the diabetic state per se also induces an increase in the generation of oxygen-derived free radicals (OFRs). There is some evidence, however, that glycation itself may induce the formation of OFRs. OFRs could cause oxidative damage to endogenous molecules. We examined the relationship between the levels of lipid peroxidation and the levels of glycated hemoglobin A1c (GHbA1c) in erythrocytes of diabetic and healthy subjects. Lipid peroxidation was assessed in erythrocyte membrane lipids by monitoring peak height ratios of conjugated linoleic acid (CLA), one of the products of lipid peroxidation, to linoleic acid (LA) using gas chromatography-mass spectrometry (GC/MS). CLA is a collective term used to designate a mixture of positional and geometric isomers of LA in which the double bonds are conjugated. The peak height ratio of CLA to LA was used as a biomarker of lipid peroxidation. GHbA1c, an index of glycemic stress, was measured by high-performance liquid chromatography. There were significantly increased ratios of CLA to LA in diabetic erythrocytes compared with control erythrocytes. These ratios of CLA to LA were also significantly correlated with GHbA1c values. This suggests that glycation via chronic hyperglycemia links lipid peroxidation in the erythrocytes of both diabetic and healthy subjects.


Assuntos
Diabetes Mellitus/sangue , Eritrócitos/metabolismo , Hemoglobinas Glicadas/metabolismo , Peróxidos Lipídicos/sangue , Adulto , Idoso , Membrana Eritrocítica/química , Feminino , Radicais Livres , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Ácidos Linoleicos/sangue , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Modelos Químicos
19.
Clin Chim Acta ; 159(1): 77-82, 1986 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-3757269

RESUMO

A new, simple method for the diagnosis of adrenoleukodystrophy (ALD) using a dried blood spot sample, is described. Fatty acid from the dried blood spot was extracted and methylated simultaneously with HCl-methanol. Fatty acid methyl esters were analyzed by gas chromatography-mass spectrometry. Fatty acid compositions of the blood spot from four patients with ALD and five healthy controls were determined from the mass chromatograms of the m/z 143 ion, [(CH2)6 COOCH3]+. The ratios of tetracosanoic acid to docosanoic acid (C24:0/C22:0) and hexacosanoic acid to docosanoic acid (C26:0/C22:0) were significantly greater in ALD patients than in the controls. The fatty acid composition of the dried blood spot did not change at room temperature within a week. Since the specimens can be sent by mail, this method could be applied to the screening of ALD.


Assuntos
Adrenoleucodistrofia/diagnóstico , Esclerose Cerebral Difusa de Schilder/diagnóstico , Adrenoleucodistrofia/sangue , Ácidos Graxos/sangue , Filtração/instrumentação , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Manejo de Espécimes , Temperatura
20.
Sarcoidosis Vasc Diffuse Lung Dis ; 14(1): 39-45, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9186988

RESUMO

Our previous reports demonstrated the concomitant release of IL-1 beta and IL-1 inhibitory activity in the culture supernatants of BALF macrophages in both healthy subjects and patients with interstitial lung diseases. IL-1 inhibitory activities decreased in healthy smokers (HS), and patients with sarcoidosis (Sar), or idiopathic pulmonary fibrosis (IPF), compared with those in healthy nonsmokers (HNS), though an increase in IL-1 beta release was not detected. IL-1 inhibitory activity was mainly characterized as IL-1 receptor antagonist (IL-1ra). In this study, we confirmed a decrease in IL-1ra in terms of the amounts of protein (enzyme-linked immunoassay) and gene transcripts (reverse transcriptase polymerase chain reaction followed by high performance liquid chromatography). Imbalance between IL-1ra and IL-1 beta was expressed as a molar ratio of IL-1ra/IL-1 beta protein: (Sar; 4.20 +/- 2.06, IPF; 4.26 +/- 3.41, HS; 3.44 +/- 3.09 versus NS 8.33 +/- 2.77: P < 0.001). These results were similar in terms of the amounts of gene transcripts. In conclusion, the imbalance of IL-1 beta and IL-1ra production was confirmed at three levels: biological activity, amounts of protein, and gene transcript obtained from BALF macrophages in chronic inflammatory processes in the lungs.


Assuntos
Líquido da Lavagem Broncoalveolar/citologia , Interleucina-1/metabolismo , Doenças Pulmonares Intersticiais/metabolismo , Macrófagos Alveolares/metabolismo , Sialoglicoproteínas/metabolismo , Adulto , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Primers do DNA/química , DNA Complementar/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1/genética , Japão , Doenças Pulmonares Intersticiais/patologia , Macrófagos Alveolares/patologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Sarcoidose Pulmonar/metabolismo , Sarcoidose Pulmonar/patologia , Sialoglicoproteínas/genética , Fumar/efeitos adversos , Transcrição Gênica/genética
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