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1.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(5): 907-914, 2021 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-34650293

RESUMO

OBJECTIVE: To analyze the effects of visual restoration after cataract surgery on plantar pressure and biomechanics of foot in elder individuals. METHODS: Thirty-two patients [male/female 5/27, (70.1±5.2) years old] with age-related cataract were recruited between October 2016 and December 2019. The footscan system was employed to record the data of plantar pressure during level walking before and 1-month after the cataract surgery. Parameters of peak pressure (PP), impulse (I), pressure-time integral (PTI) and time to peak pressure (TPP) from the regions of the 1st toe (T1), 2nd to 5th toes (T2-5), 1st to 5th metatarsal heads (M1-M5), midfoot (MF), medial hindfoot (HM) and lateral hindfoot (HL) were analyzed respectively. RESULTS: Post-operatively, the visual function was effectively reconstructed with improved visual acuity in both eyes (Z=-4.878, -4.801; P < 0.001). The PP (t=2.266, P=0.031) and I (t=2.152, P=0.039) values in M2 region on the dominant side (right foot) increased statistically at post-operative phase, while the changes of pressure and temporal para-meters in other regions remained stable. There was laterality in plantar pressure at pre-operative phase, manifested as greater PP values in M1, M2, MF, and HM regions on the dominant sides (t=-2.414, -2.478, -2.144, -5.269; P < 0.05), greater PP values in T1, M3, M5 and HL regions on the non-dominant sides (t=4.830, 3.155, 2.686, 3.683; P < 0.05), greater I values in M1, MF, and HM regions on the dominant sides (t=-2.380, -2.185, -5.320; P < 0.05) and greater I values in T1, M3, M5 and HL regions on the non-dominant sides (t=4.489, 2.247, 2.838, 3.992; P < 0.05). post-operatively, the pressure tended to be compatible between the two sides in regions of M3 and MF, while the magnitude of laterality in regions of M1 (ZPP△= -2.721, P=0.007; ZI△=-2.581, P=0.010), M2 (ZPP△=-2.674, P=0.007; ZI△=-2.375, P=0.018) and M5 (ZPP△=1.991, P=0.046; ZI△=2.150, P=0.032) was further increased. CONCLUSION: Changes in plantar pressure after cataract surgery were characterized as increased pressure in the 2nd metatarsal head area on the dominant side. Visual restoration might intensify the laterality in the medial of forefoot on the dominant side and the lateral of forefoot on the non-dominant side.


Assuntos
, Idoso , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão
2.
Clin Microbiol Infect ; 24(10): 1055-1063, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29208560

RESUMO

OBJECTIVES: To provide a summary of evidence for the diagnostic accuracies of three multiplex PCR systems (mPCRs)-BioFire FilmArray RP (FilmArray), Nanosphere Verigene RV+ test (Verigene RV+) and Hologic Gen-Probe Prodesse assays-on the detection of viral respiratory infections. METHODS: A comprehensive search up to 1 July 2017 was conducted on Medline and Embase for studies that utilized FilmArray, Verigene RV+ and Prodesse for diagnosis of viral respiratory infections. A summary of diagnostic accuracies for the following five viruses were calculated: influenza A virus (FluA), influenza B virus, respiratory syncytial virus, human metapneumovirus and adenovirus. Hierarchical summary receiver operating curves were used for estimating the viral detection performance per assay. RESULTS: Twenty studies of 5510 patient samples were eligible for analysis. Multiplex PCRs demonstrated high diagnostic accuracy, with area under the receiver operating characteristic curve (AUROC) equal to or more than 0.98 for all the above viruses except for adenovirus (AUROC 0.89). FilmArray, Verigene RV+ and ProFlu+ (the only Prodesse assay with enough data) demonstrated a summary sensitivity for FluA of 0.911 (95% confidence interval, 0.848-0.949), 0.949 (95% confidence interval, 0.882-0.979) and 0.954 (95% confidence interval, 0.871-0.985), respectively. The three mPCRs were comparable in terms of detection of FluA. CONCLUSIONS: Point estimates calculated from eligible studies showed that the three mPCRs (FilmArray, Verigene RV+ and ProFlu+) are highly accurate and may provide important diagnostic information for early identification of respiratory virus infections. In patients with low pretest probability for FluA, these three mPCRs can predict a low possibility of infection and may justify withholding empirical antiviral treatments.


Assuntos
Reação em Cadeia da Polimerase Multiplex/métodos , Infecções Respiratórias/diagnóstico , Viroses/diagnóstico , Vírus/genética , Humanos , Infecções Respiratórias/virologia , Viroses/virologia
3.
Cell Death Dis ; 7(6): e2290, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-27362807

RESUMO

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) show a clinical benefit when used to treat patients with EGFR-mutated non-small-cell lung cancer (NSCLC), but this treatment unfortunately fails in patients with TKI-resistant tumors. We here provide evidence that TC-N19 (N19), a novel dual inhibitor of EGFR and cMET, efficiently overcomes the EGFR-TKI resistance in EGFR-mutated NSCLC cells via simultaneous degradation of both proteins by ubiquitin proteasomes. Comparison with HSP90 inhibitor treatment and knockdown of EGFR and cMET by small hairpin RNAs reveal that the reduction of EGFR and cMET expression by N19 is responsible for overcoming the intrinsic TKI resistance mediated by paxillin (PXN) in high PXN-expressing cells, PXN-overexpressing PC9 cells (PC9-PXN), the EGFR-T790M-mediated TKI resistance in H1975 and CL97 cells, and the acquired resistance to gefitinib in gefitinib-resistant PC9 cells (PC9GR). Annexin V-PI staining assay showed that the induction of apoptosis in NSCLC cells by N19 depended on the reduction in levels of both proteins. Xenograft tumor formation in nude mice induced by a PC9-PXN-stable clone and by PC9GR cells was nearly completely suppressed by N19 treatment, with no changes in animal body weight. MTT assays of normal lung cells and reticulocytes showed no cytotoxicity responses to N19. In summary, N19 may act as a novel dual inhibitor of EGFR and cMET that induces apoptosis in TKI-resistant EGFR-mutated NSCLC cells and suppresses xenograft tumor formation. We suggest that N19 may be a potential new-generation TKI or HSP90 inhibitor used for treatment of NSCLC patients who show resistance to current TKI-targeting therapies.


Assuntos
Antraquinonas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Neoplasias Pulmonares/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Receptores ErbB/metabolismo , Gefitinibe , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/metabolismo , Quinazolinas/farmacologia , Ensaio Tumoral de Célula-Tronco , Ubiquitina/metabolismo , Ubiquitinação/efeitos dos fármacos
4.
Cell Death Differ ; 18(11): 1791-804, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21566658

RESUMO

Znf179 is a member of the RING finger protein family. During embryogenesis, Znf179 is expressed in a restricted manner in the brain, suggesting a potential role in nervous system development. In this report, we show that the expression of Znf179 is upregulated during P19 cell neuronal differentiation. Inhibition of Znf179 expression by RNA interference significantly attenuated neuronal differentiation of P19 cells and a primary culture of cerebellar granule cells. Using a microarray approach and subsequent functional annotation analysis, we identified differentially expressed genes in Znf179-knockdown cells and found that several genes are involved in development, cellular growth, and cell cycle control. Flow cytometric analyses revealed that the population of G0/G1 cells decreased in Znf179-knockdown cells. In agreement with the flow cytometric data, the number of BrdU-incorporated cells significantly increased in Znf179-knockdown cells. Moreover, in Znf179-knockdown cells, p35, a neuronal-specific Cdk5 activator that is known to activate Cdk5 and may affect the cell cycle, and p27, a cell cycle inhibitor, also decreased. Collectively, these results show that induction of the Znf179 gene may be associated with p35 expression and p27 protein accumulation, which lead to cell cycle arrest in the G0/G1 phase, and is critical for neuronal differentiation of P19 cells.


Assuntos
Diferenciação Celular , Proteínas de Ligação a DNA/metabolismo , Células-Tronco de Carcinoma Embrionário/citologia , Neurônios/citologia , Animais , Bromodesoxiuridina/farmacologia , Células Cultivadas , Quinase 5 Dependente de Ciclina/antagonistas & inibidores , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Células-Tronco de Carcinoma Embrionário/metabolismo , Fase G1 , Pontos de Checagem da Fase G1 do Ciclo Celular , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurogênese/genética , Neurônios/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fase de Repouso do Ciclo Celular , Tretinoína/farmacologia
5.
Neuroscience ; 170(2): 390-8, 2010 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-20670675

RESUMO

L-DOPA therapy for Parkinson's disease has a double-edge effect on nigrostriatal dopaminergic neurons: L-DOPA increases the intracellular level of dopamine, but it induces neuron cytotoxicity in a concentration-dependent manner. To investigate the molecular signaling mechanisms that underlie the concentration-dependent effects of L-DOPA on cell viability, the activities of mitogen-activated protein kinases (MAPKs) and apoptotic enzymes were measured in rat adrenal pheochromocytoma (PC12) cells in the presence of a low concentration (20 muM) and high concentrations (100-200 muM) of L-DOPA. At the low concentration, L-DOPA was not cytotoxic and its presence increased the activities of extracellular signal-regulated kinase (ERK)1/2, p38 MAPK, BadSer112, Bcl-2, and caspase-12. At the high concentrations, L-DOPA was cytotoxic and stimulated the activities of ERK1/2, p38 MAPK, c-Jun N-terminal kinase (JNK)1/2, BadSer155, caspase-12 and caspase-3. The increased levels of ERK1/2 and BadSer155 in the presence of high concentrations of L-DOPA did not protect against L-DOPA-mediated cytotoxicity. In addition, the levels of L-type Ca(2+) channel-sensitive intracellular cyclic AMP (cAMP) and Ca(2+) were elevated in the presence of L-DOPA, and the increase in the levels of intracellular cAMP may also play a role in cellular viability, since cAMP levels and cytotoxicity increased in parallel with L-DOPA concentrations and the addition of forskolin in the medium increased cytotoxicity in a concentration-dependent manner. These results suggest that, at a low and non-toxic concentration, L-DOPA may promote cell survival by increasing the activities of ERK1/2, BadSer112 and Bcl-2, while, at high concentrations, L-DOPA activates the caspase-3 cell death enzyme through the JNK1/2 and p38 MAPK signaling pathways as well as endoplasmic reticulum stress that activates caspase-12. Intracellular cAMP levels may also play a role here. The results may lead to an effective therapy for Parkinson's disease.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , AMP Cíclico/metabolismo , Levodopa/toxicidade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Cálcio/metabolismo , Colforsina/toxicidade , Relação Dose-Resposta a Droga , Levodopa/administração & dosagem , Células PC12 , Ratos , Transdução de Sinais/efeitos dos fármacos
6.
Chem Pharm Bull (Tokyo) ; 49(10): 1288-91, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11605655

RESUMO

The synthesis of a series of 1,5-dichloro-9(10H)-anthracenones bearing O-linked and N-linked substituents in the 10-position are described. Previous studies have shown that 9-acyloxy 1,5-dichloroanthracenes and 9-acyloxy 1,8-dichloroanthracenes displayed a potential cytotoxic effect. These results have encouraged us in further investigation of potential anthracenone derivatives. Therefore, a series of 10-substituted 1,8-dichloro-9(10H)-anthracenone derivatives were synthesized. These compounds were evaluated for their ability to inhibit the growth of human oral epidermoid carcinoma cells (KB cell line), human cervical carcinoma cells of ME 180 (GBM 8401) and Chinese hamster ovary (CHO) cells, respectively. Compounds 3c and 4c of this series compare favorably in the KB cellular assay with mitoxantrone. Compound 4c showed combined inhibitory action against KB, GBM and CHO cell growth, respectively. In addition, redox property of the compounds for the inhibition of lipid peroxidation in model membranes was determined. Compounds 4b and 4d exhibited stronger antioxidant activity than ascorbic acid, (+)-alpha-tocopherol and mitoxantrone, respectively.


Assuntos
Antracenos/síntese química , Antibióticos Antineoplásicos/síntese química , Antibióticos Antineoplásicos/toxicidade , Antioxidantes/síntese química , Antioxidantes/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacos , Animais , Antracenos/toxicidade , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Indicadores e Reagentes , Modelos Moleculares , Ratos , Ratos Wistar , Espectrofotometria Ultravioleta , Células Tumorais Cultivadas
7.
Chem Pharm Bull (Tokyo) ; 49(10): 1346-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11605668

RESUMO

The synthesis and cytotoxic evaluation of 9-acyloxy 1,8-dichloroanthracene derivatives are described. The system selectively reduces the carbonyl group flanked by the peri substituents of the anthracenediones to give the corresponding 1,8-dichloro-9(10H)-anthracenone. Simple acylation of anthracenone occurred with appropriate acyl chlorides in CH2Cl2 with a catalytic amount of pyridine to give the 9-acyloxy-1,8-dichloroanthracene derivatives. Considerable interest has developed in the mechanism of how anthracenones achieve this desirable selectivity. These compounds were evaluated in vitro for their ability to inhibit the growth of human oral epidermoid carcinoma cells (KB cell line), human cervical carcinoma cells of ME 180 (GBM 8401) and Chinese hamster ovary (CHO) cells, respectively, as compared to mitoxantrone. The in vitro cytotoxicity evaluation of 9-acyloxy 1,8-dichloroanthracenes against these above cell lines revealed for most of the compounds a cytotoxic potency lower than that of mitoxantrone. The most active compounds were thus selected for further in vitro biological evaluation and structural modification.


Assuntos
Antracenos/síntese química , Antracenos/farmacologia , Antibióticos Antineoplásicos/síntese química , Antibióticos Antineoplásicos/farmacologia , Animais , Células CHO , Cricetinae , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Indicadores e Reagentes , Células KB , Espectroscopia de Ressonância Magnética , Espectrofotometria Infravermelho , Células Tumorais Cultivadas
8.
J Formos Med Assoc ; 100(8): 548-52, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11678006

RESUMO

BACKGROUND AND PURPOSE: To compare the concentrations of two fluoroquinolones, ofloxacin (OFLX) and norfloxacin (NFLX), in the prostate glands of patients who underwent transurethral resection of the prostate (TUR-P) after oral ingestion of both drugs for surgical prophylaxis. METHODS: Ten patients with clinical symptoms of benign prostatic hyperplasia undergoing TUR-P received 200 mg of both drugs per os simultaneously 2 hours before surgery. The concentrations of the drugs in the serum and prostate at the time of surgery were measured by high performance liquid chromatography. Patients' clinical characteristics were evaluated, including findings from transrectal ultrasonography of the prostate, prostate specific antigen concentration, renal function tests, and post-operative status. RESULTS: Two hours after administration, the mean serum concentration of OFLX was 4.14 +/- 0.64 mg/L (range 0.27-6.37) and of NFLX was 1.10 +/- 0.22 mg/L (range 0.02-2.1). The concentration of ORLX in prostatic tissue was 4.10 +/- 0.79 micrograms/g (range 1.70-6.37) and of NFLX was 2.22 +/- 0.57 micrograms/g (range 0.63-4.35). The ratio of the prostatic tissue concentration (P) to the serum concentration (S) was 2.11 for OFLX and 5.71 for NFLX. The concentrations of both drugs exceeded the minimum inhibitory concentration (MIC) for most gram-negative organisms, but NFLX may be unable to exceed the MIC90 of Enterobacter cloacae in some individuals. Leukocytosis and spiking fever developed after TUR-P in two of the 10 patients. CONCLUSIONS: Concentrations of OFLX were higher in both serum and prostatic adenoma tissues than those of NFLX (p < 0.001), while NFLX had better penetration into the prostate (P/S ratio) (p < 0.001). The results of this study indicated that the concentrations of both of these drugs exceeded the MIC for most gram-negative organisms.


Assuntos
Anti-Infecciosos/farmacocinética , Norfloxacino/farmacocinética , Ofloxacino/farmacocinética , Complicações Pós-Operatórias/prevenção & controle , Próstata/metabolismo , Hiperplasia Prostática/cirurgia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/metabolismo , Infecções Urinárias/prevenção & controle
9.
Chem Pharm Bull (Tokyo) ; 49(8): 969-73, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11515587

RESUMO

The synthetically useful approaches to 9-acyloxy 1,5-dichloroanthracene derivatives are reported. The system selectively reduces the carbonyl group flanked by the peri substituents of the anthracenediones to give the corresponding 1,5-dichloro-9(10H)-anthracenone. Simple regioselective acylation of anthracenone is applied with appropriate acyl chlorides in CH2Cl2 with catalytic amount of pyridine to give the novel 9-acyloxy 1,5-dichloroanthracene derivatives. Considerable interest has developed in the mechanism of how anthracenone achieves this desirable selectivity. In an attempt to understand the mechanism of this reaction, solid-state structures of anthracene derivatives have been obtained. In addition, the inhibition of lipid peroxidation in model membranes was determined as was their ability to inhibit the telomere-addition function of the human telomerase enzyme together with their inhibition of the Taq polymerase enzyme. In contrast to (+)-alpha-tocopherol, 3b, 3c, 3d, 3g, and 3i do not enhance lipid peroxidation in model membranes. Implications for 9-acyloxy 1,5-dichloroanthracene analogues as potential anticancer agents are discussed.


Assuntos
Antracenos/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Telomerase/antagonistas & inibidores , Acilação , Animais , Antracenos/química , Antraquinonas/química , Antraquinonas/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Humanos , Peroxidação de Lipídeos/fisiologia , Ratos , Ratos Wistar , Telomerase/metabolismo
10.
J Biochem ; 128(4): 673-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11011150

RESUMO

Molecular cloning of the gene and the crystal structure of the prolyl aminopeptidase [EC 3.4.11.5] from Serratia marcescens have been studied by us [J. Biochem. 122, 601-605 (1997); ibid. 126, 559-565 (1999)]. Through these studies, Phe139, Tyr149, Glu204, and Arg136 were estimated to be concerned with substrate recognition. To elucidate the details of the mechanism for the substrate specificity, the site-directed mutagenesis method was applied. The F139A mutant showed an 80-fold decrease in catalytic efficiency (k(cat)/K(m)), but the Y149A mutant did not show a significant change in catalytic efficiency. The catalytic efficiency of the E204Q mutant was about 4% of that of the wild type. The peptidase activity of the mutant (R136A) was markedly decreased, however, arylamidase activity with Pyr-bNA was retained as in the wild-enzyme. From these results, it was clarified that the pyrrolidine ring and the amino group of proline at the S1 site were recognized by Phe139 and Glu204, respectively. P1' of a substrate was recognized by Arg136. On the other hand, the enzyme had two cysteine residues. Mutants C74A and C271A were inhibited by PCMB, but the double mutated enzyme (C74/271A) was resistant to it.


Assuntos
Aminopeptidases/metabolismo , Prolina/metabolismo , Serratia marcescens/enzimologia , Aminopeptidases/antagonistas & inibidores , Aminopeptidases/química , Aminopeptidases/genética , Sítios de Ligação , Catálise , Cisteína/genética , Cisteína/metabolismo , Cinética , Modelos Moleculares , Mutagênese Sítio-Dirigida/genética , Mutação/genética , Peptídeos/química , Peptídeos/metabolismo , Prolina/genética , Estrutura Secundária de Proteína/efeitos dos fármacos , Especificidade por Substrato , Ácido p-Cloromercurobenzoico/farmacologia
11.
Artigo em Inglês | MEDLINE | ID: mdl-10882192

RESUMO

Regulation of arachidonate metabolism in human epidermoid carcinoma A431 cells by phospholipid hydroperoxide glutathione peroxidase (PHGPx) and cytosolic glutathione peroxidase (GPx1) was studied. In order to study the effect of reduced glutathione (GSH) on the catalysis regulation of these oxygenation enzymes, diethyl maleate was used to deplete the intracellular GSH. In the presence of 13-hydroperoxyoctadecadienoic acid, the enzymatic catalysis of cyclooxygenase and 12-lipoxygenase was significantly increased in the GSH-depleted cells. In terms of the inhibitory effect on 12-lipoxygenase, PHGPx was more sensitive to GSH concentrations than GPx1. Inhibition of PHGPx activity by the treatment of cells with antisense oligonucleotide of PHGPx mRNA increased the enzymatic catalysis of both cyclooxygenase and 12-lipoxygenase. In conclusion, the results indicate that catalysis of cyclooxygenase and 12-lipoxygenase in A431 cells was regulated by redox-reaction, and PHGPx seems to play an important role in the controlling of these reactions.


Assuntos
Araquidonato 12-Lipoxigenase/metabolismo , Glutationa Peroxidase/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Ácido Araquidônico/metabolismo , Plaquetas/enzimologia , Plaquetas/metabolismo , Carcinoma de Células Escamosas , Catálise , Fracionamento Celular , Glutationa/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/isolamento & purificação , Humanos , Metabolismo dos Lipídeos , Oligonucleotídeos Antissenso/farmacologia , Oxirredução , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Células Tumorais Cultivadas
12.
J Cell Biochem ; 79(1): 58-70, 2000 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-10906755

RESUMO

Stress susceptibility in pigs is inherited by a single recessive gene (Hal(n)), and homozygous individuals can be identified by exposure to halothane anesthesia. Previous studies have shown that in stress-susceptible pigs, exposure to a high ambient temperature resulted in a twofold increase in corticotropin (ACTH) and lower plasma cortisol. To determine whether there is a fundamental difference in adrenocortical function between halothane-sensitive (HAL-S) and halothane-resistant (HAL-R) pigs, independent of other factors influencing the hypothalamic-pituitary-adrenal (HPA) axis, we compared cortisol responses to ACTH and 8-bromo-cyclic AMP (8-Br-cAMP) in HAL-S and HAL-R pig adrenocortical cells in vitro. We also determined directly the accumulation of four different mRNAs encoding cholesterol side-chain cleavage cytochrome P450 (P450(scc)), 17alpha-hydroxylase cytochrome P450 (P450(17alpha)), 21-hydroxylase cytochrome P450 (P450(c21)) and 11beta-hydroxylase cytochrome P450 (P450(11beta)) in HAL-S pig adrenal cells and compared them to HAL-R pigs. A time- and dose-dependent increase in medium content of cortisol and cAMP was observed after ACTH treatment. 8-Br-cAMP also caused a time- and dose-dependent increase in cortisol production in the medium. Addition of ACTH or 8-Br-cAMP to HAL-S and HAL-R male Lanyu small-ear miniature pig adrenocortical cells increased cortisol production in a dose- and time-related manner. However, cells isolated from HAL-S pigs had a lower cortisol production in response to ACTH or 8-Br-cAMP compared to those from HAL-R pigs. Treatment of cultured cells with 8-Br-cAMP (0.5 mM) for 18 h resulted in a significant increase in P450(scc), P450(17alpha), P450(c21), and P450(11beta) mRNA levels. In the absence of 8-Br-cAMP, the four genes were expressed constitutively in both HAL-S and HAL-R pig adrenal cells. Densitometric scanning of the autoradiograph indicated that the relative amounts of P450(scc) and P450(17(alpha)) mRNAs in HAL-S pig adrenal cells were between 48% and 53% of those detected in HAL-R pig adrenal cells (P < 0.05). No difference in the amounts of P450(c21) and P450(11beta) was seen in HAL-S and HAL-R pig adrenal cells. Addition of 8-Br-cAMP (0.5 mM) resulted in a uniform increase in the levels of all four P450 mRNAs in both HAL-S and HAL-R pig adrenal cells. However, the amounts of P450(scc) mRNA in HAL-S pig adrenal cells were 67% (P < 0.05) of those measured in HAL-R pig adrenal cells, whereas the amounts of P450(17alpha ), P450(c21), and P450(11beta) mRNAs were similar in these cells. Our data suggest an HPA axis defect in HAL-S pigs at the adrenal level. This defect appears to be at the level of P450scc gene expression, which could be partially related to reduced cortisol production by ACTH stimulation.


Assuntos
Córtex Suprarrenal/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/genética , Halotano/farmacologia , Hidrocortisona/biossíntese , RNA Mensageiro/genética , Córtex Suprarrenal/citologia , Córtex Suprarrenal/enzimologia , Córtex Suprarrenal/metabolismo , Hormônio Adrenocorticotrópico/farmacologia , Animais , AMP Cíclico/biossíntese , Relação Dose-Resposta a Droga , Masculino , RNA Mensageiro/metabolismo , Suínos , Porco Miniatura
13.
BJU Int ; 85(9): 1143-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10848711

RESUMO

OBJECTIVE: To evaluate the possible role of free radicals in nephrolithiasis in rats induced by ethylene glycol, and to examine the correlation between the urinary enzymes N-acetyl-beta-glucosaminidase (NAG), beta-galactosidase (GAL) and neutral endopeptidase (NEP), and free radical production. MATERIALS AND METHODS: Hyperoxaluria was produced in male Wistar rats by adding ethylene glycol to their drinking water. After 7, 21 and 42 days of treatment, urinary oxalate, creatinine clearance and urinary enzymes (NAG, GAL and NEP) were measured. The nitroblue tetrazolium perfusion method was used to locate the sites of free-radical production. Ultrasensitive chemiluminescence was used to directly measure the production of reactive oxygen species (ROS) in vivo. Vitamin E and potassium citrate were fed to rats, in addition to ethylene glycol, to assess their effects on free radical production. RESULTS: Urinary oxalate increased significantly and was associated with an increase in NAG and GAL at all sample times. However, urinary NEP activity was unchanged on day 7, although there was four times as much NEP on days 21 and 42 than in the control groups. Formazan particles in the renal cortex were scored as 3+ to 4+ in rats treated for 7 days with ethylene glycol. Blood ROS levels were also higher in this group than in the controls (P < 0.01). After vitamin E and potassium citrate treatment, blood ROS levels were lower than in rats treated with ethylene glycol alone. CONCLUSION: Free radicals may be produced in the early stages of nephrolithiasis in rats fed with ethylene glycol. Free radicals occurred mainly in blood and might be associated with NEP inactivation.


Assuntos
Hiperoxalúria/metabolismo , Cálculos Renais/induzido quimicamente , Animais , Etilenoglicol , Radicais Livres/metabolismo , Hiperoxalúria/induzido quimicamente , Cálculos Renais/metabolismo , Medições Luminescentes , Masculino , Ratos , Ratos Wistar
15.
Prostaglandins Other Lipid Mediat ; 58(2-4): 65-75, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10560610

RESUMO

The partially purified phospholipid hydroperoxide glutathione peroxidase (PHGPx) from A431 cells was used to systematically compare the inhibitory effect on the enzyme activity of various lipoxygenases and cyclooxygenases. Under the standard assay system, platelet 12-lipoxygenase, 15-lipoxygenase, and cyclooxygenase-2 were the most sensitive to the inhibition by PHGPx. 5-Lipoxygenase and cyclooxygenase-1 were less sensitive to the inhibition by PHGPx than platelet 12-lipoxygenase and cyclooxygenase-2, respectively, and the difference was approximately 10-fold. Reduction of 12(S)-hydroperoxyeicosatetraenoic acid to 12(S)-hydroxyeicosatetraenoic acid by PHGPx was observed in the presence of glutathione (GSH), and the inhibitory effect of PHGPx on 12-lipoxygenase-catalyzed arachidonate metabolism was reversed by the addition of exogenous lipid hydroperoxide. The results indicate that PHGPx directly reduced lipid hydroperoxides and then down-regulated the activity of arachidonate oxygenases. Moreover, a high-level expression of PHGPx mRNA and its 12-lipoxygenase-inhibitory activity was observed in cancer cells and endothelial cells, and these results suggest that PHGPx may play a significant role in the regulation of reactive oxygen species formation in these cells.


Assuntos
Inibidores de Ciclo-Oxigenase/farmacologia , Glutationa Peroxidase/farmacologia , Inibidores de Lipoxigenase/farmacologia , Animais , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Regulação para Baixo/efeitos dos fármacos , Humanos , Isoenzimas/metabolismo , Leucotrienos/metabolismo , Ácidos Linoleicos/metabolismo , Peroxidação de Lipídeos , Peróxidos Lipídicos/metabolismo , Lipoxigenase/metabolismo , Proteínas de Membrana , Oxirredução , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Prostaglandina-Endoperóxido Sintases/metabolismo , RNA Mensageiro/metabolismo , Proteínas Recombinantes , Células Tumorais Cultivadas
16.
FEBS Lett ; 455(1-2): 111-6, 1999 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-10428483

RESUMO

Promoter activation in the expression of phospholipid hydroperoxide glutathione peroxidase (PHGPx) gene in human epidermoid carcinoma A431 cells was studied in the present investigation. Luciferase reporter assays with plasmids carrying a 400 bp of the promoter DNA were performed to analyze the regulatory element in the proximal promoter of human PHGPx gene. Transient transfection with a series of 5'-deletion and internal truncation mutants showed that the 5'-flanking region spanning from -212 to -121 bp was important for the basal expression of PHGPx gene in A431 cells. A region from -170 to -140 bp was protected in DNase I footprinting assays and bound the nuclear proteins in electrophoretic mobility shift assays. This region, denoted FP3, contains the consensus recognition sites for AP-2, CCAAT-box and CRE. The oligonucleotide competitor with the mutation at CCAAT-box could not eliminate the nuclear protein binding in gel-shift assay and the site-directed mutagenesis at the CCAAT-box decreased the luciferase activity of PHGPx promoter for approximate 50% in reporter gene assays. Competition experiments indicate that the binding of nuclear factor to the FP3 region was abolished by oligodeoxyribonucleotide corresponding to NF-Y/CP1 binding site to a greater extent than by those corresponding to sites for CTF/NFI and C/EBP. Taken together, the CCAAT-box in the promoter ranging from -156 to -151 bp, bound to NF-Y/CP1, was essential for the basal expression of human PHGPx gene in A431 cells.


Assuntos
Carcinoma de Células Escamosas/enzimologia , Proteínas de Ligação a DNA/metabolismo , Regulação Enzimológica da Expressão Gênica , Glutationa Peroxidase/genética , Proteínas Estimuladoras de Ligação a CCAAT , Carcinoma de Células Escamosas/patologia , DNA , Humanos , Luciferases/genética , Mutagênese Sítio-Dirigida , Proteínas Nucleares/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Células Tumorais Cultivadas
17.
J Formos Med Assoc ; 97(10): 673-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9830276

RESUMO

To analyze the characteristics and prognostic factors of penile cancer in Taiwanese, we retrospectively reviewed the clinical data of patients with a diagnosis of penile cancer treated during a 20-year period (1977-1996) at National Taiwan University Hospital (NTUH). Of 71 patients treated for penile cancer during the study period, 17 were referred from other hospitals or clinics. Our analyses focused on the 54 previously untreated patients. Growth on the penis was the main symptom in all cases. Palpable inguinal lymph nodes were found only in 14 patients. All 54 patients with primary tumors were treated surgically. Pathologic examination showed squamous cell carcinoma (SCC) in 43 cases, extra-mammary Paget's disease in three, verrucous carcinoma in three, Bowen's disease in two, cutaneous lymphoma in two and basal cell carcinoma in one. Twenty-six (48%) patients had stage I penile cancer, 13 (24%) had stage II, seven (13%) had stage III, and eight (15%) had stage IV cancer. The five-year survival rate was 78% among patients with SCC and 84% among those with nonsquamous malignancies (p = 0.80). The five-year cumulative survival rates according to Jackson's cancer stage were 100% for patients with stage I, 88.9% for those with stage II, 66.7% for those with stage III, and 0% for those with stage IV (p < 0.001). Tumor staging (p = 0.027) and adjuvant chemotherapy (p = 0.042) were found to be the most significant prognostic factors. Penile cancer accounted for 0.254% of all malignancies among male patients at the NTUH during the study period. Our findings indicate that penile cancer is uncommon in Taiwanese and its prognosis is closely related to tumor staging and management. Early diagnosis and appropriate treatment may lead to prolonged survival.


Assuntos
Neoplasias Penianas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Penianas/diagnóstico , Neoplasias Penianas/terapia , Prognóstico , Estudos Retrospectivos , Taiwan/epidemiologia
18.
J Endocrinol Invest ; 21(7): 428-33, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9766256

RESUMO

Langerhans cell histiocytosis (LCH) is a rare disorder and may be complicated with hypopituitarism and diabetes insipidus (DI) due to invasion of the hypothalamic-pituitary area. In this study, 10 patients with complete (4) and partial (6) type central DI were found among 125 LCH patients in our hospital records. The water deprivation test, followed by the pitressin test, was performed to confirm DI. Hypothalamic-pituitary endocrine function tests were carried out on these 10 patients at the initial diagnosis and during follow-up. All patients revealed growth hormone insufficiency in the insulin hypoglycemic tolerance test. Four patients had impairment of cortisol secretion, demonstrated by insulin hypoglycemic stimulating test results. Two patients had poor response in the thyrotropin releasing hormone stimulating test. Two patients had only partial responses in the luteinizing hormone releasing hormone test. Four patients had hyperprolactinemia. All patients underwent surgical treatment followed by chemotherapy and/or radiotherapy. One patient completely recovered from the endocrine disorder, 3 patients required smaller doses of desmopressin, and one patient had normal adrenal, thyroid, and gonadal function. Hypothalamic-pituitary disorders in LCH should not be neglected. Treatment of LCH can partially or completely reverse associated endocrine disorders. Therefore, endocrine studies and hormone replacement should be mandatory for patients with LCH.


Assuntos
Diabetes Insípido/fisiopatologia , Glândulas Endócrinas/fisiopatologia , Histiocitose de Células de Langerhans/fisiopatologia , Adolescente , Adulto , Medula Óssea/patologia , Criança , Pré-Escolar , Diabetes Insípido/complicações , Diabetes Insípido/patologia , Feminino , Histiocitose de Células de Langerhans/complicações , Histiocitose de Células de Langerhans/patologia , Terapia de Reposição Hormonal , Hormônios/sangue , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Testes de Função Hipofisária , Adeno-Hipófise/fisiopatologia , Estudos Retrospectivos
19.
Otolaryngol Head Neck Surg ; 118(5): 728-31, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9591882

RESUMO

Anaplastic thyroid carcinoma is one of the most lethal neoplasms, with poor prognosis being reported by most authors. The benefits of surgery for most cases of advanced disease remain controversial. In this study we asked the following question: Does surgical intervention alter outcomes for patients with advanced anaplastic thyroid carcinoma? Forty-six patients with advanced anaplastic thyroid carcinoma were analyzed. There were 20 patients with advanced localized disease (group 1), 15 of whom received surgery. Of the other 26 patients with evidence of distant metastases (group 2), 13 received surgery. For group 1 patients, the mean survival was 12.8 months versus 8.6 months in the surgical and nonsurgical subgroups (p = 0.46). For group 2 patients, the mean survival was 3.5 months versus 2.8 months in the surgical and nonsurgical subgroups (p = 0.72). These data suggest that surgery does not improve survival for patients with advanced anaplastic thyroid carcinoma. In conclusion, the mean survival showed no significant differences between surgical and nonsurgical patients (p = 0.43). This study suggests that surgical resection does not improve the survival of patients with advanced anaplastic thyroid carcinoma.


Assuntos
Carcinoma/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Carcinoma/patologia , Carcinoma/secundário , Feminino , Humanos , Neoplasias Pulmonares/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Taxa de Sobrevida , Neoplasias da Glândula Tireoide/patologia , Resultado do Tratamento
20.
FEBS Lett ; 424(1-2): 22-6, 1998 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-9537508

RESUMO

An endogenous lipoxygenase inhibitor, purified from the cytosol of human epidermoid carcinoma A431 cells, was analyzed by N-terminal microsequencing and mass spectrometric analysis. The inhibitor was purified by SDS-PAGE, then subjected to in-gel CNBr cleavage and trypsin digestion. The N-terminal sequence data obtained from a 6-8 kDa band of in-gel CNBr cleavage and the three isolated peptides of in-gel trypsin digestion, and the C-terminal peptide sequence from matrix-assisted laser desorption ionization mass spectrometry matched the sequence of human phospholipid hydroperoxide glutathione peroxidase. The purified inhibitor exhibited peroxidase activity using phosphatidylcholine hydroperoxides as the substrate. We therefore concluded that the lipoxygenase inhibitor present in A431 cells was a phospholipid hydroperoxide glutathione peroxidase.


Assuntos
Glutationa Peroxidase/isolamento & purificação , Inibidores de Lipoxigenase/isolamento & purificação , Sequência de Aminoácidos , Glutationa Peroxidase/química , Humanos , Inibidores de Lipoxigenase/química , Espectrometria de Massas , Dados de Sequência Molecular , Mapeamento de Peptídeos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Fosfolipídeos/metabolismo , Células Tumorais Cultivadas/enzimologia
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