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1.
Nanotechnology ; 34(7)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36332230

RESUMO

Hierarchical domain structures associated with oxygen octahedra tilting patterns were observed in lead-free (Bi1/2Na1/2)TiO3ceramics using aberration-corrected high-resolution transmission electron microscopy (HRTEM). Three types of domains are induced by distinct mechanisms: the 'orientation-domain' is induced at micrometer scale formed by different tilting orientations of the oxygen octahedra, the 'meso-chemical-domain' occurs at a few tens of nanometer scale by chemical composition variation on the A-site in the ABO3perovskite structure, and the 'nano-cluster-region' runs across several unit-cells with apparent A-site cation segregation with oxygen vacancies clustering around Na cations. Based on HRTEM amplitude contrast imaging (ACI), the correlation between the oxygen octahedral tilting pattern and compositional non-stoichiometry was established. The role of the hierarchical domain structure associated with the tilting patterns of the oxygen octahedra on the ferroelectric behavior of (Bi1/2Na1/2)TiO3is also discussed.

2.
Pharmazie ; 70(9): 581-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26492642

RESUMO

Niemann-Pick C1-like 1 (NPC1L1i) protein is the key transporter responsible for dietary cholesterol absorption. Recent studies indicated that several functional polymorphisms of NPC1L1 were associated with coronary heart disease (CHD) and response to ezetimibe therapy. The aim of the present study was to analyze the allele frequency and haplotype distribution of NPC1L1 polymorphisms in Chinese Hans and to compare them with those of other ethnic populations reported before. Blood samples were collected from 424 unrelated Chinese Hans (246 males and 178 females). Ten NPC1L1 polymorphisms (-762T > C, -133A > G, -18C > A, 1721C > T, 1735C > G, 1764T > C, 1767G > A, 27677T > C, 25342A > C and 28650A > G) were genotyped by direct sequencing or polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Among the variants, the minor allele frequency of -762T > C and 1735C > G were 35.0% and 37.0%, respectively. Furthermore, these two polymorphisms were highly linked with a D' value of 0.80. The observed frequencies of two major haplotypes were 59.1% for T-762/C1735 and 30.1% for C-762/G1735, respectively. The frequencies of the rest variants were extremely low (1.8% for - 133G, 1.5% for -18A, 0.9% for 1721T and only 0.2% for 27677C allele, respectively) or even not detected (1764T > C, 1767G > A, 25342A > C and 28650A > G) in our study population. Comparison with other ethnic populations revealed a remarkable genetic variability in the incidences of NPC1L1 polymorphisms. The frequencies of NPC1L1 polymorphisms in Chinese Hans are comparable to Japanese population but totally different from Caucasians, African-Americans and Hispanic individuals. This is the first study to report the ethnic difference in the frequencies of NPC1L1 functional polymorphisms in detail. -762T > C and 1735C > G are two prevalent NPC1L1 variants which need further studies to explore their clinical impact on CHD prevalence and response to ezetimibe therapy in Chinese Hans.


Assuntos
Proteínas de Membrana/genética , Adulto , Alelos , Povo Asiático , China/epidemiologia , Feminino , Frequência do Gene , Genótipo , Haplótipos , Humanos , Masculino , Proteínas de Membrana Transportadoras , Pessoa de Meia-Idade , Polimorfismo Genético/genética
3.
Pharmazie ; 69(10): 775-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25985569

RESUMO

This study was designed to investigate the potential association between NTCP c.800C >T polymorphism and rosuvastatin pharmacokinetics in Chinese healthy males. 305 individuals were enrolled to identify NTCP c.800C > T, OATP1B1 c.521T > C and BCRP c.421C > A genotypes by direct sequencing and pyrosequencing methods, respectively. 17 healthy volunteers who were OATP1B1 c.521TT and BCRP c.421CC wild-type homozygotes with different NTCP c.800C > T genotype were selected to participate in this pharmacokinetic study. Nine were NTCP c.800CC wild-type homozygotes and the other eight subjects were carriers with at least one c.800T variant allele (seven subjects with c.800CT genotype and one was homozygote of c.800TT). All the subjects received a single oral dose of 10 mg rosuvastatin. The plasma concentrations of rosuvastatin were measured up to 72 h by a LC-MS method. NTCP c.800C > T genetic polymorphism markedly effected rosuvastatin pharmacokinetics. The AUC(o-72) and AUC(0 --> ∞) in subjects with NTCP c.800CT + TT genotype were 56% (162.64 ± 37.55 vs. 103.99 ± 28.15 ng x h/ml, P = 0.016) and 57% greater (178.51 ± 42.75 vs. 113.60 ± 33.73 ng x h/ml, P = 0.020) than those in the c.800CC wild-type subjects, respectively. In the c.800CT + TT mutant group, the C(max) was about 78% higher than those in c.800CC genotype (14.31 ± 3.63 vs. 8.04 ± 1.72 ng x h/ml, P = 0.004). The oral clearance (CL/F) of rosuvastatin in subjects with the c.800CT+TT genotype was only 63% of those in the c.800CC genotype (58.32 ± 12.16 vs. 93.04 ± 20.61 ng x h/ml, P = 0.009). The half-time (T1/2) and the T(max) had no significant difference between two groups (p = 0.466 and 0.713, respectively). NTCP c.800C > T polymorphism play a critical role in the individual variability of rosuvastatin pharmacokinetics in Chinese healthy males after excluding the impact of OATP1B1 c.521T > C and BCRP c.421C > A polymorphisms.


Assuntos
Fluorbenzenos/farmacocinética , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacocinética , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Pirimidinas/farmacocinética , Sulfonamidas/farmacocinética , Simportadores/genética , Adulto , Área Sob a Curva , Povo Asiático , China/epidemiologia , Frequência do Gene , Humanos , Masculino , Polimorfismo Genético/genética , Rosuvastatina Cálcica
4.
Elife ; 122024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488852

RESUMO

Dysregulated pre-mRNA splicing and metabolism are two hallmarks of MYC-driven cancers. Pharmacological inhibition of both processes has been extensively investigated as potential therapeutic avenues in preclinical and clinical studies. However, how pre-mRNA splicing and metabolism are orchestrated in response to oncogenic stress and therapies is poorly understood. Here, we demonstrate that jumonji domain containing 6, arginine demethylase, and lysine hydroxylase, JMJD6, acts as a hub connecting splicing and metabolism in MYC-driven human neuroblastoma. JMJD6 cooperates with MYC in cellular transformation of murine neural crest cells by physically interacting with RNA binding proteins involved in pre-mRNA splicing and protein homeostasis. Notably, JMJD6 controls the alternative splicing of two isoforms of glutaminase (GLS), namely kidney-type glutaminase (KGA) and glutaminase C (GAC), which are rate-limiting enzymes of glutaminolysis in the central carbon metabolism in neuroblastoma. Further, we show that JMJD6 is correlated with the anti-cancer activity of indisulam, a 'molecular glue' that degrades splicing factor RBM39, which complexes with JMJD6. The indisulam-mediated cancer cell killing is at least partly dependent on the glutamine-related metabolic pathway mediated by JMJD6. Our findings reveal a cancer-promoting metabolic program is associated with alternative pre-mRNA splicing through JMJD6, providing a rationale to target JMJD6 as a therapeutic avenue for treating MYC-driven cancers.


Assuntos
Neuroblastoma , Precursores de RNA , Sulfonamidas , Humanos , Animais , Camundongos , Precursores de RNA/genética , Precursores de RNA/metabolismo , Glutaminase/genética , Reprogramação Metabólica , Histona Desmetilases com o Domínio Jumonji/metabolismo
5.
IEEE Trans Med Imaging ; 42(10): 3069-3079, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37167043

RESUMO

Clarifying the morphological characteristics of neurons can promote the understanding of brain function. However, traditional morphometrics fail to capture the modeling of each point in reconstructed neurons, leading to limited ability to distinguish massive nerve fibers and restricted application scenarios. To address these challenges, we propose MorphoGNN, a single neuron morphological embedding based on a graph neural network in this study. MorphoGNN learns the point-level structure information of reconstructed nerve fibers by considering their nearest neighbors on each hidden layer. This enables MorphoGNN to capture the lower-dimensional representation of a single neuron through an end-to-end model. In order to meet the requirements of various tasks, both supervised and self-supervised training strategies are designed to learn the characteristics that fit artificial semantics or the morphological patterns of neurons, respectively. We quantitatively compare our embeddings with other features in neuron classification and retrieval tasks and demonstrate cutting-edge performance. Additionally, we introduce our embeddings to the task of reconstruction quality classification and neuron clustering, where they can help detect reconstruction errors and obtain similar subtyping results to existing work. Furthermore, our method can be handily combined with other modal features, such as microscopic image features and traditional morphometrics. Ablation and robustness tests are also conducted to analyze the impact of several network components and low-quality reconstructed neurons on the performance of our method. The code is available at https://github.com/fun0515/MorphoGNN.


Assuntos
Fibras Nervosas , Neurônios , Análise por Conglomerados , Redes Neurais de Computação , Percepção
6.
bioRxiv ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37425900

RESUMO

Dysregulated pre-mRNA splicing and metabolism are two hallmarks of MYC-driven cancers. Pharmacological inhibition of both processes has been extensively investigated as potential therapeutic avenues in preclinical and clinical studies. However, how pre-mRNA splicing and metabolism are orchestrated in response to oncogenic stress and therapies is poorly understood. Here, we demonstrate that Jumonji Domain Containing 6, Arginine Demethylase and Lysine Hydroxylase, JMJD6, acts as a hub connecting splicing and metabolism in MYC-driven neuroblastoma. JMJD6 cooperates with MYC in cellular transformation by physically interacting with RNA binding proteins involved in pre-mRNA splicing and protein homeostasis. Notably, JMJD6 controls the alternative splicing of two isoforms of glutaminase (GLS), namely kidney-type glutaminase (KGA) and glutaminase C (GAC), which are rate-limiting enzymes of glutaminolysis in the central carbon metabolism in neuroblastoma. Further, we show that JMJD6 is correlated with the anti-cancer activity of indisulam, a "molecular glue" that degrades splicing factor RBM39, which complexes with JMJD6. The indisulam-mediated cancer cell killing is at least partly dependent on the glutamine-related metabolic pathway mediated by JMJD6. Our findings reveal a cancer-promoting metabolic program is associated with alternative pre-mRNA splicing through JMJD6, providing a rationale to target JMJD6 as a therapeutic avenue for treating MYC-driven cancers.

7.
Br J Clin Pharmacol ; 74(6): 999-1004, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22519658

RESUMO

AIMS: This study aimed to investigate the effect of metamizole on bupropion hydroxylation related to different CYP2B6 genotype groups in healthy volunteers. METHODS: Sixteen healthy male volunteers (6 CYP2B6*1/*1, 6 CYP2B6*1/*6 and 4 CYP2B6*6/*6) received orally administered bupropion alone and during daily treatment with metamizole 1500 mg day(-1) (500 mg tablet taken three times daily) for 4 days. Serial blood samples were obtained up to 48 h after each bupropion dose. RESULTS: After metamizole treatment relative to bupropion alone, the geometric mean ratios (GMRs) and 90% confidence interval (CI) of the AUC(0,∞) ratio of 4-hydroxybupropion over bupropion were 1.99 (1.57, 2.55) for the CYP2B6*1/*1 group, 2.15 (1.53, 3.05) for the CYP2B6*1/*6 group and 1.86 (1.36, 2.57) for the CYP2B6*6/*6 group. The GMRs and 90% CI of bupropion were 0.695 (0.622, 0.774) for AUC(0,∞) and 0.400 (0.353, 0.449) for C(max) , respectively. The corresponding values for 4-hydroxybupropion were 1.43 (1.28, 1.53) and 2.63 (2.07, 2.92). The t(1/2) value was significantly increased for bupropion and decreased for 4-hydroxybupropion. The t(max) values of bupropion and 4-hydroxybupropion were both significantly decreased. The mean percentage changes in pharmacokinetic parameters among the CYP2B6 genotype groups were not significantly different. CONCLUSIONS: Oral administration of metamizole for 4 days significantly altered the pharmacokinetics of both bupropion and its active metabolite, 4-hydroxybupropion, and significantly increased the CYP2B6-catalyzed bupropion hydroxylation in all of the subjects. Cautions should be taken when metamizole is co-administered with CYP2B6 substrate drugs.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antidepressivos de Segunda Geração/farmacocinética , Bupropiona/farmacocinética , Dipirona/farmacologia , Administração Oral , Anti-Inflamatórios não Esteroides/administração & dosagem , Área Sob a Curva , Hidrocarboneto de Aril Hidroxilases/genética , Povo Asiático/genética , Citocromo P-450 CYP2B6 , Dipirona/administração & dosagem , Interações Medicamentosas , Genótipo , Humanos , Hidroxilação , Masculino , Oxirredutases N-Desmetilantes/genética , Adulto Jovem
8.
Cancers (Basel) ; 14(7)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35406427

RESUMO

Increased TERT mRNA is associated with disease relapse in favorable histology Wilms tumor (WT). This study sought to understand the mechanism of increased TERT expression by determining the association between TERT and WT1 and N-MYC, two proteins important in Wilms tumor pathogenesis that have been shown to regulate TERT expression. Three out of 45 (6.7%) WTs and the corresponding patient-derived xenografts harbored canonical gain-of-function mutations in the TERT promoter. This study identified near ubiquitous hypermethylation of the TERT promoter region in WT compared to normal kidney. WTs with biallelic inactivating mutations in WT1 (7/45, 15.6%) were found to have lower TERT expression by RNA-seq and qRT-PCR and lower telomerase activity determined by the telomerase repeat amplification protocol. Anaplastic histology and increased percentage of blastema were positively correlated with higher TERT expression and telomerase activity. In vitro shRNA knockdown of WT1 resulted in decreased expression of TERT, reduced colony formation, and decreased proliferation of WiT49, an anaplastic WT cell line with wild-type WT1. CRISPR-Cas9-mediated knockout of WT1 resulted in decreased expression of telomere-related gene pathways. However, an inducible Wt1-knockout mouse model showed no relationship between Wt1 knockout and Tert expression in normal murine nephrogenesis, suggesting that WT1 and TERT are coupled in transformed cells but not in normal kidney tissues. N-MYC overexpression resulted in increased TERT promoter activity and TERT transcription. Thus, multiple mechanisms of TERT activation are involved in WT and are associated with anaplastic histology and increased blastema. This study is novel because it identifies potential mechanisms of TERT activation in Wilms tumor that could be of therapeutic interests.

9.
J Pharm Biomed Anal ; 200: 114077, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33892396

RESUMO

Drug resistance and adverse reactions to oxaliplatin remain a considerable issue in clinical practice. Emerging evidence has suggested that alterations in the lipid metabolism during drug therapy affect cancer cells. To gain insight into the important process of lipid metabolism, we investigated the lipid and gene expression profile changes in HT29 cells treated with oxaliplatin. A total of 1403 lipid species from 16 lipid classes were identified by UHPLC-MS. Interestingly, phospholipids, including phosphatidylglycerol (PG), phosphatidic acid (PA), phosphatidylcholine (PC), and most of phosphatidylethanolamine (PE) with polyunsaturated fatty acid (PUFA) chains, were significantly higher due to oxaliplatin treatment, while triacylglycerols (TAGs) with a saturated fatty acid chain or monounsaturated fatty acid were significantly downregulated. Gene Set Enrichment Analysis (GSEA) based on RNA sequencing data suggested that neutral lipid metabolism was enriched in the control group, whereas the phospholipid metabolic process was enriched in the oxaliplatin-treated group. We observed that altered lipid metabolism enzyme genes were involved in the synthesis and lipolysis of TAGs and the Lands cycle pathway based on the network between the core lipid-related gene and lipid species, which was further verified by qRT-PCR. In summary, our findings revealed that oxaliplatin impressed a specific lipid profile signature and lipid transcriptional reprogramming in HT29 cells, which provides new insights into biomarker discovery and pathways for overcoming drug resistance and adverse reactions.


Assuntos
Neoplasias Colorretais , Lipidômica , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Humanos , Metabolismo dos Lipídeos/genética , Oxaliplatina , Fosfolipídeos , Transcriptoma
10.
Nat Commun ; 12(1): 7204, 2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34893606

RESUMO

The H3K27me2/me3 histone demethylase KDM6B is essential to neuroblastoma cell survival. However, the mechanism of KDM6B action remains poorly defined. We demonstrate that inhibition of KDM6B activity 1) reduces the chromatin accessibility of E2F target genes and MYCN, 2) selectively leads to an increase of H3K27me3 but a decrease of the enhancer mark H3K4me1 at the CTCF and BORIS binding sites, which may, consequently, disrupt the long-range chromatin interaction of MYCN and E2F target genes, and 3) phenocopies the transcriptome induced by the specific CDK4/6 inhibitor palbociclib. Overexpression of CDK4/6 or Rb1 knockout confers neuroblastoma cell resistance to both palbociclib and the KDM6 inhibitor GSK-J4. These data indicate that KDM6B promotes an oncogenic CDK4/6-pRB-E2F pathway in neuroblastoma cells via H3K27me3-dependent enhancer-promoter interactions, providing a rationale to target KDM6B for high-risk neuroblastoma.


Assuntos
Quinase 4 Dependente de Ciclina/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/genética , Neuroblastoma/metabolismo , Oncogenes/genética , Linhagem Celular Tumoral , Quinase 4 Dependente de Ciclina/genética , Epigenômica , Regulação Neoplásica da Expressão Gênica , Histona Desmetilases/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Proteína Proto-Oncogênica N-Myc/genética , Fatores de Transcrição
11.
Ann Pharmacother ; 44(6): 1038-45, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20484172

RESUMO

BACKGROUND: Curcumin is a kind of plant polyphenol that is extracted from the rhizome of Curcuma longa. Studies about the effect of curcumin on the activity of drug-metabolizing enzymes in humans are lacking. OBJECTIVE: To investigate the effect of curcumin on the activities of CYP1A2, CYP2A6, N-acetyltransferase (NAT2), and xanthine oxidase (XO) in vivo, using caffeine as a probe drug. METHOD: Sixteen unrelated, healthy Chinese men were recruited for the study. There were 2 phases in the study. In the first phase, volunteers orally received 100 mg caffeine and 0- to 12-hour blood and urine samples were collected. In the second phase, volunteers received 1000 mg curcumin once daily for 14 continuous days, and blood and urine samples were collected on day 15, following the same procedure used on the first day. Urinary caffeine metabolite ratios were used as the indicators of the activities of CYP1A2, CYP2A6, NAT2, and XO. The pharmacokinetics of caffeine and its metabolites were determined by high-performance liquid chromatography. RESULTS: In the curcumin-treated group, CYP1A2 activity was decreased by 28.6% (95% CI 15.6 to 41.8; p < 0.000), while increases were observed in CYP2A6 (by 48.9%; 95% CI 25.3 to 72.4; p < 0.000). Plasma area under the curve from zero to 12 hours of 1,7-dimethylxanthine (17X) was decreased by 27.2% (95% CI 6.1 to 48.3; p = 0.014). The urinary excretion of 17X and 1-methylxanthine was significantly decreased by 36.4% (95% CI 19.4 to 53.6; p < 0.000) and 31.2% (95% CI 8.5 to 54.1; p = 0.010), respectively. The excretion of 1,7-dimethylurate (17U) was significantly increased by 77.3% (95% CI 5.6 to 148.8; p = 0.036). No significant changes were observed for caffeine, 1-methylurate, and 5-acetylamino-6-formylamino-3-methyluracil between the 2 study phases. CONCLUSIONS: The results indicated that curcumin inhibits CYP1A2 function but enhances CYP2A6 activity. Simultaneously, some pharmacokinetic parameters relating to 17X were affected by curcumin. If this finding is confirmed by other studies, the possibility of herb-drug interactions associated with curcumin should be considered in clinical practice.


Assuntos
Hidrocarboneto de Aril Hidroxilases/biossíntese , Povo Asiático , Curcumina/farmacocinética , Inibidores do Citocromo P-450 CYP1A2 , Flavonoides/farmacocinética , Fenóis/farmacocinética , Adolescente , Adulto , Hidrocarboneto de Aril Hidroxilases/metabolismo , Cafeína/farmacocinética , Estudos Cross-Over , Curcumina/química , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2A6 , Regulação para Baixo/efeitos dos fármacos , Flavonoides/química , Interações Ervas-Drogas/fisiologia , Humanos , Masculino , Fenóis/química , Extratos Vegetais/farmacocinética , Polifenóis , Regulação para Cima/efeitos dos fármacos , Adulto Jovem
12.
Eur J Clin Pharmacol ; 66(8): 805-810, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20393696

RESUMO

BACKGROUND: Glycyrrhizin is a major ingredient of licorice which is widely used in the treatment of various diseases such as chronic hepatitis. Licorice or glycyrrhizin has been shown to alter the activity of CYP3A in rodents. The influence of glycyrrhizin on CYP3A has not been elucidated in humans. OBJECTIVE: To investigate the effects of repeated glycyrrhizin ingestion on the oral pharmacokinetics of midazolam, a probe drug for CYP3A activity in humans. METHODS: Sixteen healthy adult male subjects were enrolled in a two-phase randomized crossover design. In each phase the volunteers received placebo or glycyrrhizin for 14 days. On the 15th day, midazolam was administered and blood samples were obtained to determine midazolam plasma concentrations. Bioequivalence was assessed by determining geometric mean ratios (GMRs) and 90% confidence intervals (90% CI). RESULTS: The geometric mean (geometric coefficient of variation) for the AUC(0-infinity) of midazolam in the placebo group was 196.4 ng x h/ml (30.3%) and after glycyrrhizin treatment, 151.3 ng x h/ml (34.7%). The GMRs and 90% CI for AUC(0-infinity) and Cmax of midazolam in the presence/ absence of glycyrrhizin were 0.77 (0.70, 0.89) and 0.83 (0.74, 1.01), respectively. The 90% CI for AUC(0-infinity) and Cmax for the GMR of glycyrrhizin over placebo were both out of the no-effect boundaries of 0.80-1.25. CONCLUSIONS: Administration of glycyrrhizin resulted in a modest induction of CYP3A that was clinically relevant according to the bioequivalence analysis.


Assuntos
Anti-Inflamatórios/farmacologia , Citocromo P-450 CYP3A/metabolismo , Ácido Glicirrízico/farmacologia , Midazolam/farmacocinética , Adolescente , Adulto , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Área Sob a Curva , Estudos Cross-Over , Método Duplo-Cego , Ácido Glicirrízico/química , Ácido Glicirrízico/metabolismo , Meia-Vida , Humanos , Masculino , Taxa de Depuração Metabólica , Midazolam/sangue , Estrutura Molecular , Equivalência Terapêutica
13.
Br J Clin Pharmacol ; 68(2): 201-6, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19694739

RESUMO

AIMS: To assess the effects of Ginkgo biloba extract on the pharmacokinetics of bupropion in healthy volunteers. METHODS: Fourteen healthy male volunteers (age range 19-25 years) received orally administered bupropion (150 mg) alone and during treatment with G. biloba 240 mg day(-1) (two 60-mg capsules taken twice daily) for 14 days. Serial blood samples were obtained over 72 h after each bupropion dose, and used to derive pharmacokinetic parameters of bupropion and its CYP2B6-catalysed metabolite, hydroxybupropion. RESULTS: Ginkgo biloba extract administration resulted in no significant effects on the AUC(0-infinity) of bupropion and hydroxybupropion. Bupropion mean AUC(0-infinity) value was 1.4 microg.h ml(-1)[95% confidence interval (CI) 1.2, 1.6] prior to G. biloba treatment and 1.2 microg.h ml(-1) (95% CI 1.1, 1.4) after 14 days of treatment. Hydroxybupropion mean AUC(0-infinity) value was 8.2 microg.h ml(-1) (95% CI 6.5, 10.4) before G. biloba administration and 8.7 microg.h ml(-1) (95% CI 7.1, 10.6) after treatment. The C(max) of hydroxybupropion increased from 221.8 ng ml(-1) (95% CI 176.6, 278.6) to 272.7 ng ml(-1) (95% CI 215.0, 345.8) (P = 0.038) and the t(1/2) of hydroxybupropion fell from 25.0 h (95% CI 22.7, 27.5) to 21.9 h (95% CI 19.9, 24.1) (P = 0.000). CONCLUSIONS: Ginkgo biloba extract administration for 14 days does not significantly alter the basic pharmacokinetic parameters of bupropion in healthy volunteers. Although G. biloba extract treatment appears to reduce significantly the t(1/2) and increase the C(max) of hydroxybupropion, no bupropion dose adjustments appear warranted when the drug is administered orally with G. biloba extract, due to the lack of significant change observed in AUC for either bupropion or hydroxybupropion.


Assuntos
Antidepressivos/farmacocinética , Bupropiona/análogos & derivados , Ginkgo biloba/metabolismo , Extratos Vegetais/farmacocinética , Administração Oral , Adulto , Bupropiona/farmacocinética , Cromatografia Líquida de Alta Pressão , Métodos Epidemiológicos , Interações Ervas-Drogas/fisiologia , Humanos , Masculino , Adulto Jovem
14.
Ann Pharmacother ; 43(6): 1045-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19458107

RESUMO

BACKGROUND: osartan is metabolized by CYP2C9 and CYP3A4 to an active metabolite, E-3174, which has greater antihypertensive activity than the parent compound. Soy extract has been shown to be an activator of CYP2C9 and CYP3A4 in vitro. Coadministration of soy extract and losartan may therefore alter the pharmacokinetics of losartan and E-3174. OBJECTIVE: To determine whether, when losartan was used in combination with soy extract, a significant pharmacokinetic interaction would be observed in healthy female volunteers. METHODS: Eighteen healthy Chinese female volunteers were recruited. In an open-label, 2-phase study, losartan 50 mg was given to each subject, with and without soy extract. Plasma concentrations of losartan and E-3174 were determined by liquid chromatography-tandem mass spectrometry for 12 and 24 hours, respectively. On day 8 through day 21 of the study, following a 7-day washout period, each subject consumed two 1000-mg Genistein Soy Complex tablets orally after meals, twice daily, for 14 days. On day 22, all volunteers received losartan 50 mg and blood samples were collected again. RESULTS: All subjects completed the study, without adverse drug effects. Over the 14-day pretreatment period, soy extract did not significantly influence the pharmacokinetics of losartan or E-3174. The ratio of the area under the curve of the drug and metabolite after losartan administration, with and without soy extract ingestion, was 0.21 +/- 0.05 and 0.23 +/- 0.05 (mean +/- SD), respectively. The difference was not statistically significant (p = 0.22). CONCLUSIONS: Our data indicate that a significant interaction between soy extract and losartan is unlikely to occur in females.


Assuntos
Antiarrítmicos/farmacocinética , Glycine max/química , Losartan/farmacocinética , Extratos Vegetais/farmacologia , Área Sob a Curva , Hidrocarboneto de Aril Hidroxilases/efeitos dos fármacos , Hidrocarboneto de Aril Hidroxilases/metabolismo , China , Cromatografia Líquida , Citocromo P-450 CYP2C9 , Citocromo P-450 CYP3A/efeitos dos fármacos , Citocromo P-450 CYP3A/metabolismo , Feminino , Humanos , Imidazóis/farmacocinética , Espectrometria de Massas em Tandem , Tetrazóis/farmacocinética , Fatores de Tempo , Adulto Jovem
15.
Ann Pharmacother ; 43(5): 944-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19401473

RESUMO

BACKGROUND: Ginkgo biloba extract (GBE), the best selling herbal medicine in the world, has been reported to inhibit P-glycoprotein in vitro. However, the effects of GBE on P-glycoprotein activity in humans have not been clarified. OBJECTIVE: To investigate the effects of single and repeated GBE ingestion on the oral pharmacokinetics of talinolol, a substrate drug for P-glycoprotein in humans. METHODS: Ten unrelated healthy male volunteers were selected to participate in a 3-stage sequential study. Plasma concentrations of talinolol from 0 to 24 hours were measured by high-performance liquid chromatography after talinolol 100 mg was administrated alone, with a single oral dose of GBE (120 mg), and after 14 days of repeated GBE ingestion (360 mg/day). RESULTS: A single oral dose of GBE did not affect the pharmacokinetics of talinolol. Repeated ingestion of GBE increased the talinolol maximum plasma concentration (C(max)) by 36% (90% CI 10 to 68; p = 0.025), the area under the concentration-time curve (AUC)(0-24) by 26% (90% CI 11 to 43; p = 0.008) and AUC(0-infinity) by 22% (90% CI 8 to 37; p = 0.014), respectively, without significant changes in elimination half-life and the time to C(max). CONCLUSIONS: Our results suggest that long-term use of GBE significantly influenced talinolol disposition in humans, likely by affecting the activity of P-glycoprotein and/or other drug transporters.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/efeitos adversos , Ginkgo biloba/efeitos adversos , Propanolaminas/farmacocinética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antagonistas Adrenérgicos beta/farmacocinética , Adulto , Povo Asiático , Interações Ervas-Drogas , Humanos , Masculino , Fatores de Tempo
16.
Eur J Clin Pharmacol ; 65(3): 281-5, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18982321

RESUMO

AIM: To study the pharmacokinetic characteristics of voriconazole in healthy Chinese male volunteers in relation to cytochrome P450 (CYP) 2C19 genotype status, including ultra-rapid metabolizers (URMs), homozygous extensive metabolizers (EMs), and poor metabolizers (PMs). METHOD: Twenty healthy Chinese male volunteers were recruited for the study. Of these, four were CYP2C19 heterozygous URMs (*1/*17), eight were CYP2C19 homozygous EMs (*1/*1), and eight were CYP2C19 PMs (*2/*2). After a single oral dose of 200 mg voriconazole, plasma concentrations of voriconazole were determined for a 24-h period by liquid chromatography-mass spectrometry/mass spectrometry. RESULT: In Chinese male subjects, the allele frequencies of the CYP2C19*17 and CYP2C19*2 alleles were 0.64 and 35.6%, respectively, and both alleles were in Hardy-Weinberg equilibrium. The area under the concentration-time curve (AUC) from predose to 24 h (AUC(0-24)) and from predose to infinity (AUC(0-infinity)), and apparent oral clearance (CL/F) of voriconazole were statistically different among all three genotypic groups (P < 0.001, respectively). The maximum plasma concentration (C(max)) value of URMs also showed statistically significant differences from those of EMs and PMs (P = 0.036 and P = 0.035, respectively). The elimination half-life (t(1/2)) in URMs was 87% (P = 0.58) of that in EMs and 51% (P= 0.002) of that in PMs. CONCLUSION: Our data indicate that the presence of the CYP2C19*17 allele results in ultra-rapid metabolism of voriconazole after a single oral dose.


Assuntos
Antifúngicos/farmacocinética , Hidrocarboneto de Aril Hidroxilases/genética , Pirimidinas/farmacocinética , Triazóis/farmacocinética , Antifúngicos/sangue , Área Sob a Curva , Hidrocarboneto de Aril Hidroxilases/metabolismo , Povo Asiático , China , Citocromo P-450 CYP2C19 , Genótipo , Humanos , Masculino , Pirimidinas/sangue , Triazóis/sangue , Voriconazol , Adulto Jovem
17.
Eur J Clin Pharmacol ; 65(4): 403-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19066872

RESUMO

PURPOSE: This study investigated the effect of the herbal medicine baicalin on bupropion hydroxylation, a probe reaction for CYP2B6 activity related to different CYP2B6 genotype groups. METHOD: Seventeen healthy male volunteers (6 CYP2B6*1/*1, 6 CYP2B6*1/*6, and 5 CYP2B6*6/*6) received orally administered bupropion alone and during daily treatment with baicalin. Blood samples were taken up to 72 h after each bupropion dose, and pharmacokinetics profiles were determined on days 1 and 25 for bupropion and hydroxybupropion. RESULT: Baicalin administration increased hydroxybupropion maximum plasma concentration (C(max)) by 73% [90% confidence interval (CI), 44-108%; P < 0.01] and the area under the concentration time curve extrapolated to infinity (AUC(0-infinity)) of hydroxybupropion by 87% (90% CI, 48-137%; P < 0.01), with no change in the elimination half-life of hydroxybupropion. Baicalin increased the AUC(0-infinity) ratio of hydroxybupropion to bupropion by 63% (90% CI, 38-92%; P < 0.01). CONCLUSION: Baicalin significantly induced CYP2B6-catalyzed bupropion hydroxylation, and the effects of baicalin on other CYP2B6 substrate drugs deserve further investigation.


Assuntos
Hidrocarboneto de Aril Hidroxilases/biossíntese , Hidrocarboneto de Aril Hidroxilases/efeitos dos fármacos , Bupropiona/análogos & derivados , Bupropiona/metabolismo , Flavonoides/farmacologia , Oxirredutases N-Desmetilantes/biossíntese , Oxirredutases N-Desmetilantes/efeitos dos fármacos , Extratos Vegetais/farmacologia , Adulto , Área Sob a Curva , Bupropiona/sangue , Bupropiona/farmacocinética , Citocromo P-450 CYP2B6 , Inibidores da Captação de Dopamina/metabolismo , Indução Enzimática/efeitos dos fármacos , Flavonoides/química , Glucuronidase/antagonistas & inibidores , Haplótipos , Interações Ervas-Drogas , Humanos , Hidroxilação/efeitos dos fármacos , Masculino , Extratos Vegetais/química , Polimorfismo de Nucleotídeo Único , Fatores de Tempo
18.
Eur J Clin Pharmacol ; 65(7): 679-83, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19396436

RESUMO

OBJECTIVE: To evaluate the impact of the DRD2 TaqIA and DRD3 Ser9Gly polymorphisms on the efficacy of pramipexole in treating patients with Parkinson's disease (PD). METHODS: Thirty patients with PD prospectively received pramipexole 0.25 mg three times daily for 2 months. Unified Parkinson Disease Rating Scale (UPDRS) assessments were conducted at baseline and 2 months after treatment initiation. Improvement by 20% or more in the total score on the UPDRS was considered to indicate responsiveness. The PCR-restriction fragment length polymorphism analysis was used to analyze the DRD2 Taq1A and DRD3 Ser9Gly genotype. RESULTS: The DRD2 Taq1A allele frequencies were A141.7 (A1) and 58.3% (A2), and the DRD3 Ser9Gly allele frequencies were 68.3 (Ser) and 31.7% (Gly). When the subjects were grouped by the DRD3 Ser9Gly polymorphism, the response rates for pramipexole treatment were significantly higher in the Ser/Ser group (60%) than in the group containing the Gly allele (13%). There was a significant association between the DRD3 Ser9Gly polymorphism and response rate to pramipexole in PD patients (P = 0.024). When the subjects were grouped by the DRD2 Taq1A polymorphism, there were no significant differences among the three Taq1A genotypes. CONCLUSIONS: DRD3 Ser9Gly polymorphisms are significantly associated with the therapeutic efficacy of pramipexole in Chinese patients with PD. A large-scale and multi-dose group study in patients with PD is necessary for evaluating the impact of the genetic polymorphisms of the dopamine receptor on the therapeutic effects of pramipexole.


Assuntos
Benzotiazóis/uso terapêutico , Agonistas de Dopamina/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Receptores de Dopamina D2/genética , Receptores de Dopamina D3/genética , Idoso , Alelos , Povo Asiático/estatística & dados numéricos , DNA/sangue , DNA/genética , DNA/isolamento & purificação , Esquema de Medicação , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Pramipexol , Resultado do Tratamento
19.
Eur J Clin Pharmacol ; 65(6): 601-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19172254

RESUMO

OBJECTIVE: To investigate the interaction between allicin and omeprazole and to observe the effects of allicin on CYP2C19 and CYP3A4 activity in healthy Chinese male volunteers with different CYP2C19 genotypes. METHODS: Eighteen subjects (six CYP2C19*1/CYP2C19*1, four CYP2C19*1/CYP2C19*2, two CYP2C19*1/ CYP2C19*3, and six CYP2C19*2/ CYP2C19*2) were enrolled in a two-phase randomized crossover trial. In each phase, all subjects received placebo or a 180 mg allicin capsule once daily for 14 consecutive days. The pharmacokinetics of omeprazole (20 mg orally on day 15) was determined for up to 12 h following administration by high-performance liquid chromatography. RESULTS: In carriers of the CYP2C19*1/CYP2C19*1 and CYP2C19*1/CYP2C19*2 or *3 genotype, allicin treatment increased the peak plasma concentration (C(max)) of omeprazole by 49.7 +/- 7.2 (p < 0.001) and 54.2 +/- 9.2% (p < 0.001), and increased the area under the plasma time-concentration curve (AUC(0-infinity)) of omeprazole by 48.1 +/- 9.0 (p = 0.001) and 73.6 +/- 26.7% (p < 0.001), respectively. The ratio of AUC(0-infinity) of 5-hydroxyomeprazole to omeprazole (a marker for CYP2C19 activity) decreased significantly (p < 0.001 and p = 0.001, respectively). However, no pharmacokinetic parameters were significantly changed by allicin in CYP2C19*2/CYP2C19*2. The C(max) and AUC(0-infinity) of omeprazole sulfone were unchanged in all three genotypes. CONCLUSIONS: Allicin reduced the metabolism of omeprazole by inhibiting CYP2C19 activity in individuals with the CYP2C19*1/CYP2C19*1 and CYP2C19*1/CYP2C19*2 or *3 genotypes, but not in those with the CYP2C19*2/ CYP2C19*2 genotype. Allicin did not significantly affect the activity of CYP3A4 in all subjects.


Assuntos
Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP3A/metabolismo , Ácidos Sulfínicos/farmacologia , Antiulcerosos/farmacocinética , Hidrocarboneto de Aril Hidroxilases/genética , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Citocromo P-450 CYP2C19 , Dissulfetos , Genótipo , Humanos , Masculino , Omeprazol/farmacocinética , Placebos , Valores de Referência , Espectrofotometria Ultravioleta
20.
Medicine (Baltimore) ; 98(28): e16115, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31305395

RESUMO

INTRODUCTION: The benefits of magnesium sulfate for surgical field during endoscopic sinus surgery remain controversial. We conduct a systematic review and meta-analysis to explore the influence of magnesium sulfate versus placebo on surgical field during endoscopic sinus surgery. METHODS: We search PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through November 2018 for randomized controlled trials (RCTs) assessing the effect of magnesium sulfate versus placebo on surgical field during endoscopic sinus surgery. This meta-analysis is performed using the random-effect model. RESULTS: Four RCTs and 404 patients are included in the meta-analysis. Overall, compared with control group endoscopic sinus surgery, magnesium sulfate has remarkably positive impact on surgical field scores (MD = -1.76; 95% CI = -2.33 to -1.18; P < .00001), and intraoperative blood loss (MD = -89.09; 95% CI = -163.20 to -14.97; P = .02), but shows no markedly effect on surgery duration (MD = -7.08; 95% CI = -21.38 to 7.22; P = .33), fentanyl (MD = -0.64; 95% CI = -1.97 to 0.70; P = .35), and vecuronium (MD = -3.64; 95% CI = -10.99 to 3.70; P = .33). CONCLUSIONS: Magnesium sulfate exerts positive impact on surgical field and blood loss reduction for endoscopic sinus surgery.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Sulfato de Magnésio/uso terapêutico , Cirurgia Endoscópica por Orifício Natural , Vasodilatadores/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
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