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1.
Clin Radiol ; 79(2): e264-e272, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37926648

RESUMO

AIM: To determine the associations of intravoxel incoherent motion (IVIM) parameters with expression of programmed cell death-1 (PD-1) and programmed cell death ligand-1 (PD-L1), and evaluate the performance of the combined model established based on IVIM and clinicopathological parameters in predicting PD-L1and PD-1 status of cervical cancer (CC) patients. MATERIALS AND METHODS: Seventy-eight consecutive CC patients were enrolled prospectively and underwent magnetic resonance imaging (MRI) including IVIM. IVIM quantitative parameters were measured, compared, and correlated with PD-L1 and PD-1 expression. Independent factors related to PD-L1 and PD-1 positivity were identified and were used to establish the combined model. The combined model's diagnostic performance was evaluated using the receiver operating characteristic (ROC) analysis. The Shapley additive explanation (SHAP) algorithm was used to explain the contribution of each parameter in the combined model. RESULTS: The real diffusion coefficient (D) value was significantly lower in the PD-L1-positive group than in the PD-L1-negative group (0.64 ± 0.12 versus 0.72 ± 0.11, p=0.021). The PD-1-positive and PD-1-negative groups showed similar trends (0.63 ± 0.13 versus 0.73 ± 0.09, p=0.003). Parametrial invasion, lymph node status, pathological grade, FIGO (International Federation of Gynecology and Obstetrics) staging, and D values were independently associated with PD-L1 and PD-1expression. A combined model incorporating these parameters showed good discrimination with the sensitivity, specificity of 90.9%, 82.6% for PD-L1, and 93.5%, 72% for PD-1. According to the SHAP value, FIGO staging and pathological grade were the most influential features of the prediction model. CONCLUSION: IVIM parameters were found to correlate with PD-L1 and PD-1 expression. The combined model, incorporating parametrial invasion, lymph node status, pathological grade, FIGO staging, and D values, showed good discrimination in predicting PD-L1 and PD-1 status, providing the basis for CC immunotherapy.


Assuntos
Antígeno B7-H1 , Receptor de Morte Celular Programada 1 , Neoplasias do Colo do Útero , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Colo do Útero/diagnóstico por imagem , Colo do Útero/patologia , Receptor de Morte Celular Programada 1/metabolismo , Antígeno B7-H1/metabolismo , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Imageamento por Ressonância Magnética
2.
Obes Res Clin Pract ; 15(6): 593-599, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34561173

RESUMO

OBJECTIVE: To compare the extent to which visceral adiposity, as measured by mesenteric fat thickness, contribute to cardiometabolic risk, especially insulin resistance, in women with PCOS and healthy control. METHODS: This is a cross-sectional study with a total of 190 women with PCOS fulfilling the Rotterdam diagnostic criteria. Women without PCOS were recruited from a previous study, which comprised 416 healthy women controls with normal glucose tolerance. All subjects underwent OGTT, biochemical assessment, and sonographic assessment with measurements of mesenteric, preperitoneal and subcutaneous fat thickness. RESULTS: Mesenteric fat thickness was strongly correlated to cardiometabolic traits including blood pressure, fasting and 2-h glucose, triglycerides, HOMA-IR; and was negatively correlated to HDL-C in both cohorts (all p < 0.01). In PCOS, positive correlation was observed between mesenteric fat thickness and free androgen index (p < 0.01). Compared with controls, the regression line between mesenteric fat and HOMA-IR is much steeper in PCOS (p < 0.01). CONCLUSION: Women with PCOS remain more insulin resistant compared to controls at any given degree of visceral adiposity.


Assuntos
Doenças Cardiovasculares , Resistência à Insulina , Síndrome do Ovário Policístico , Adiposidade , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , China , Estudos Transversais , Feminino , Humanos , Síndrome do Ovário Policístico/complicações
4.
Palliat Support Care ; 19(5): 530-539, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33267934

RESUMO

OBJECTIVES: Families facing end-stage nonmalignant chronic diseases (NMCDs) are presented with similar symptom burdens and need for psycho-social-spiritual support as their counterparts with advanced cancers. However, NMCD patients tend to face more variable disease trajectories, and thus may require different anticipatory supports, delivered in familiar environments. The Life Rainbow Programme (LRP) provides holistic, transdisciplinary, community-based end-of-life care for patients with NMCDs and their caregivers. This paper reports on the 3-month outcomes using a single-group, pre-post comparison. METHOD: Patients with end-stage NMCDs were screened for eligibility by a medical team before being referred to the LRP. Patients were assessed at baseline (T0), 1 month (T1), and 3 months (T2) using the Integrated Palliative Outcome Scale (IPOS). Their hospital use in the previous month was also measured by presentations at accident and emergency services, admissions to intensive care units, and number of hospital bed-days. Caregivers were assessed at T0 and T2 using the Chinese version of the Modified Caregiver Strain Index, and self-reported health, psychological, spiritual, and overall well-being. Over-time changes in outcomes for patients, and caregivers, were tested using paired-sample t-tests, Wilcoxon-signed rank tests, and chi-square tests. RESULTS: Seventy-four patients and 36 caregivers participated in this research study. Patients reported significant improvements in all IPOS domains at both 1 and 3 months [ranging from Cohen's d = 0.495 (nausea) to 1.793 (depression and information needs fulfilled)]. Average hospital bed-days in the previous month fell from 3.50 to 1.68, comparing baseline and 1 month (p < 0.05). At 3 months, caregiver strain was significantly reduced (r = 0.332), while spiritual well-being was enhanced (r = 0.333). SIGNIFICANCE: After receiving 3 month's LRP services, patients with end-stage NMCDs and their caregivers experienced significant improvements in the quality of life and well-being, and their hospital bed-days were reduced.


Assuntos
Cuidadores , Qualidade de Vida , Doença Crônica , Humanos , Cuidados Paliativos , Poder Psicológico
5.
Plant Dis ; 101(1): 137-143, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30682317

RESUMO

In 2009, a new citrus viral disease caused by Citrus yellow vein clearing virus (CYVCV) was discovered in China. To more effectively monitor the presence of CYVCV, a survey was conducted in 166 citrus orchards from 11 major citrus-growing provinces in China from May 2014 to April 2016. In all, 458 of a total of 2,350 citrus samples tested positive for CYVCV, demonstrating that the virus is widely distributed in China. In this study, the complete genome sequences of 19 CYVCV isolates from different provinces and hosts were sequenced and characterized. Comparisons of the whole-genome sequences of these 19 CYVCV isolates as well as 4 isolates previously reported from around the world revealed that the sequence identity ranged from 97.1 to 99.8%, indicating that there is a very low level of sequence heterogeneity among CYVCV isolates of different geographic origins and hosts. Phylogenetic analysis of these 23 genomic sequences suggested that all of the isolates from China were clustered into the same clade, clearly apart from the CYVCV isolates from Turkey and Pakistan. To our knowledge, this is the first extensive survey conducted in China for CYVCV incidence.

6.
Rev Sci Instrum ; 87(5): 053122, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27250407

RESUMO

Ultralow-frequency (ULF) Raman spectroscopy becomes increasingly important in the area of two-dimensional (2D) layered materials; however, such measurement usually requires expensive and nonstandard equipment. Here, the measurement of ULF Raman signal down to 10 cm(-1) has been realized with high throughput by combining a kind of longpass edge filters with a single monochromator, which are verified by the Raman spectrum of L-cystine using three laser excitations. Fine adjustment of the angle of incident laser beam from normal of the longpass edge filters and selection of polarization geometry are demonstrated how to probe ULF Raman signal with high signal-to-noise. Davydov splitting of the shear mode in twisted (2+2) layer graphenes (t(2+2)LG) has been observed by such system in both exfoliated and transferred samples. We provide a direct evidence of twist-angle dependent softening of the shear coupling in t(2+2)LG, while the layer-breathing coupling at twisted interfaces is found to be almost identical to that in bulk graphite. This suggests that the exfoliation and transferring techniques are enough good to make a good 2D heterostructures to demonstrate potential device application. This Raman system will be potentially applied to the research field of ULF Raman spectroscopy.

7.
J Periodontal Res ; 51(3): 366-75, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26364593

RESUMO

BACKGROUND AND OBJECTIVE: The aim of this 12 mo prospective study was to assess the effect of smoking cessation on periodontal tissue without periodontal intervention, using matrix metalloproteinase (MMP)-8, MMP-9 and interleukin (IL)-1ß in gingival crevicular fluid, and nicotine and cotinine in saliva. MATERIAL AND METHODS: Of the 122 male smokers enrolled in a smoking cessation clinic, 11 quitters, nine non-quitters, six oscillators and 13 non-smokers participated in all experiments done at follow-up week 2, and follow-up months 2, 4, 6 and 12. The following were measured: gingival index; dental plaque index and sites of 3.5 mm < probing depth < 5.5 mm using a WHO probe for the full mouth; amounts of MMP-8, MMP-9 and IL-1ß in gingival crevicular fluid of the upper anterior teeth area using enzyme-linked immunosorbent assay; and concentrations of nicotine, cotinine and hydroxycotinine in saliva using high-performance liquid chromatography-tandem mass spectrometry. RESULTS: No significant differences in MMP-8 and MMP-9 in gingival crevicular fluid were detected between smokers, quit-smokers, oscillators and non-smokers for 1 year. Only the amount of IL-1ß showed that smokers (90.14 ± 65.32 pg/mL) had a significantly higher value compared with non-smokers (37.70 ± 40.90 pg/mL), quit-smokers (32.11 ± 40.50 pg/mL) and oscillators (11.90 ± 12.46 pg/mL) at 2 mo follow-up (p = 0.007). IL-1ß had a positive correlation with nicotine (r = 0.351) and the cotinine (r = 0.376), nicotine (r = 0.492) and hydroxycotinine (r = 0.358), and hydroxycotinine (r = 0.413) levels at 2 wk and 4 and 6 mo follow-up, respectively. CONCLUSIONS: This 1-year prospective smoking cessation study without nonsurgical periodontal therapy shows IL-1ß in gingival crevicular fluid could have a positive relationship with the nicotine and cotinine levels in saliva.


Assuntos
Biomarcadores/análise , Líquido do Sulco Gengival/química , Periodonto/química , Abandono do Hábito de Fumar , Adulto , Cotinina/análogos & derivados , Cotinina/análise , Índice de Placa Dentária , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interleucina-1beta/análise , Masculino , Metaloproteinase 8 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Pessoa de Meia-Idade , Nicotina/análise , Perda da Inserção Periodontal , Índice Periodontal , Bolsa Periodontal , Estudos Prospectivos , Saliva/química , Fumar
8.
Genet Mol Res ; 14(3): 9034-44, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26345835

RESUMO

In this study, we identified myogenic regulatory factors (MRFs) and analyzed the correlation between MRFs and meat quality in rainbow trout. The MyoD1a and MyoD1b genes were cloned from rainbow trout using a homology cloning method. Introns 1 and 2 in the MyoD1a and MyoD1b genes were cloned and submitted to GenBank (accession Nos. FJ623462 and FJ793566). Polymorphisms of MyoD1a and MyoD1b genes were analyzed using single-strand conformation polymorphism and sequencing, respectively. Two single nucleotide polymorphisms were detected in the MyoD1 gene, located at 129G→A in exon 1 and 37 G→A in exon 2. The 37 G→A mutation in exon 2 induced the R185K amino acid change in the polypeptide chain. Seven single nucleotide polymorphisms in the MyoD2 gene were detected, including 218T→C, 224T→C, 242A→C, 246T→A, 248T→C, 305T→C, and 329C→T. The 246T→A mutation in exon 1 induced the R83K change in the polypeptide chain. In the S3 fragment, meat quality traits of genotypes AA and AB significantly differed from those of genotype BB (P < 0.05). In the S5 fragment, meat quality traits of the genotypes AA and AC were significantly different from the genotypes BB and BC (P < 0.05). These results indicate that the MyoD1a and MyoD1b genes have an important influence on meat quality or were linked to the major genes in these strains. These genes can be used to control muscle fiber traits in rainbow trout, and the mutations in the S3 and S5 fragments can be used as molecular markers for selecting rainbow trout with better meat quality traits.


Assuntos
Estudos de Associação Genética , Carne , Proteína MyoD/genética , Oncorhynchus mykiss/genética , Animais , Sequência de Bases , Éxons , Genótipo , Oncorhynchus mykiss/crescimento & desenvolvimento , Fenótipo , Polimorfismo de Nucleotídeo Único
9.
Eur Rev Med Pharmacol Sci ; 19(2): 247-55, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25683938

RESUMO

OBJECTIVE: Sorafenib, an oral multikinase inhibitor, is the proved therapy method for patients with advanced hepatocellular carcinoma (HCC). Based on heat delivery, Radiofrequency ablation (RFA) has been found to achieve complete neoplasm necrosis. It is the most widely performed percutaneous therapy for HCC. However, Study associated combined Sorafenib with RFA therapy for patients with advanced HCC has never been reported. The aim of present study is to explore the efficacy and safety of sorafenib combined with RFA therapy for the patients with medium-sized HCC. PATIENTS AND METHODS: A total of 62 patients diagnosed as HCC were involved in this study. All patients were randomly assigned to sorafenib and RFA (n=30) or RFA-alone (n=32) treatment groups. Treatment outcomes, including recurrence rates, time to progression (TTP) and adverse reactions induced by sorafenib were observed and recorded to assess the efficacy and safety of the combination method. RESULTS: During the overall follow-up period, the recurrence rate of the combination subgroup was 56.7% (17/30), and that of the RFA-alone subgroup was 87.5% (28/32) (p < 0.01). The median TTP was 17.0 months in the combination therapy vs. 6.1 months in the RFA-alone (p < 0.05). Hand-foot skin reactions were reported by 83.3% (25/30) of patients and 46.7% (14/30) reported diarrhea while the most adverse events (AEs) were mild to moderate in the combination subgroup. CONCLUSIONS: Sorafenib combined with RFA significantly decreased recurrence rates and prolonged the survival time of medium-sized HCC patients. The combination therapy is safer and more effective than the control without unexpected side effects. Furthermore, the earlier application, the better results were.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/terapia , Ablação por Cateter/métodos , Neoplasias Hepáticas/terapia , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Adulto , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Terapia Combinada , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Niacinamida/uso terapêutico , Sorafenibe , Resultado do Tratamento
10.
Ultraschall Med ; 36(4): 348-54, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25171602

RESUMO

PURPOSE: Shear wave elastography (SWE) is a new technique which provides quantitative assessment of soft tissue stiffness. The aim of this study was to assess the reliability of SWE stiffness measurements and its usefulness in evaluating post-irradiation neck fibrosis. MATERIALS AND METHODS: 50 subjects (25 patients with previous radiotherapy to the neck and 25 sex and age-matched controls) were recruited for comparison of SWE stiffness measurements (Aixplorer, Supersonic Imagine). 30 subjects (16 healthy individuals and 14 post-irradiated patients) were recruited for a reliability study of SWE stiffness measurements. SWE stiffness measurements of the sternocleidomastoid muscle and the overlying subcutaneous tissues of the neck were made. The cross-sectional area and thickness of the sternocleidomastoid muscle and the overlying subcutaneous tissue thickness of the neck were also measured. The post-irradiation duration of the patients was recorded. RESULTS: The intraclass correlation coefficients for the intraoperator and interoperator reliability of deep and subcutaneous tissue SWE stiffness ranged from 0.90-0.99 and 0.77-0.94, respectively. The SWE stiffness measurements (mean +/- SD) of deep and subcutaneous tissues were significantly higher in the post-irradiated patients (64.6 ± 46.8 kPa and 63.9 ± 53.1 kPa, respectively) than the sex and age-matched controls (19.9 ± 7.8 kPa and 15.3 ± 8.37 respectively) (p < 0.001). The SWE stiffness increased with increasing post-irradiation therapy duration in the Kruskal Wallis test (p < 0.001) and correlated with muscle atrophy and subcutaneous tissue thinning (p < 0.01). CONCLUSION: SWE is a reliable technique and may potentially be an objective and specific tool in quantifying deep and subcutaneous tissue stiffness, which in turn reflects the severity of neck fibrosis.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Pescoço/efeitos da radiação , Lesões por Radiação/diagnóstico por imagem , Dissecação , Fibrose , Humanos , Pescoço/patologia , Lesões por Radiação/patologia , Ultrassonografia de Intervenção/métodos
11.
Hum Exp Toxicol ; 33(6): 629-37, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24064908

RESUMO

Photodynamic therapy (PDT) is a novel cancer treatment based on the tumor-specific accumulation of a photosensitizer followed by irradiation with visible light, which induces selective tumor cell death via production of reactive oxygen species. To elucidate the underlying mechanisms, microarray analysis was used to analyze the changes in gene expression patterns during PDT induced by various photosensitizers. Cancer cells were subjected to four different photosensitizer-mediated PDT and the resulting gene expression profiles were compared. We identified many differentially expressed genes reported previously as well as new genes for which the functionfunctions in PDT are still unclear. Our current results not only advance the general understanding of PDT but also suggest that distinct molecular mechanisms are involved in different photosensitizer-mediated PDT. Elucidating the signaling mechanisms in PDT will provide information to modulate the antitumor effectiveness of PDT using various photosensitizers.


Assuntos
Carcinoma de Células Escamosas/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/genética , Neoplasias Bucais/genética , Análise de Sequência com Séries de Oligonucleotídeos , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Neoplasias Bucais/patologia , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carcinoma de Células Escamosas de Cabeça e Pescoço , Fatores de Tempo
12.
Artigo em Inglês | MEDLINE | ID: mdl-23679419

RESUMO

We have measured the hydration-level dependence of the single-particle dynamics of water confined in the ordered mesoporous silica MCM-41. The dynamic crossover observed at full hydration is absent at monolayer hydration. The monolayer dynamics are significantly slower than those of water in a fully hydrated pore at ambient temperatures. At low temperatures, the opposite is found to be true. These results underscore the importance of water's tetrahedral hydrogen-bond network in accounting for its low temperature dynamic properties.

13.
Rev Sci Instrum ; 83(5): 053106, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22667601

RESUMO

An improved Fourier transform infrared spectroscopy approach adapting to photoluminescence and electroluminescence measurements in mid-infrared has been developed, in which diode-pumped solid-state excitation lasers were adopted for photoluminescence excitation. In this approach, three different Fourier transform infrared modes of rapid scan, double modulation, and step scan were software switchable without changing the hardware or connections. The advantages and limitations of each mode were analyzed in detail. Using this approach a group of III-V and II-VI samples from near-infrared extending to mid-infrared with photoluminescence intensities in a wider range have been characterized at room temperature to demonstrate the validity and overall performances of the system. The weaker electroluminescence of quantum cascade lasers in mid-infrared band was also surveyed at different resolutions. Results show that for samples with relatively strong photoluminescence or electroluminescence out off the background, rapid scan mode is the most preferable. For weaker photoluminescence or electroluminescence overlapped with background, double modulation is the most effective mode. To get a better signal noise ratio when weaker photoluminescence or electroluminescence signal has been observed in double modulation mode, switching to step scan mode should be an advisable option despite the long data acquiring time and limited resolution.

14.
Xenobiotica ; 41(6): 437-44, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21319958

RESUMO

Uridine 5'-diphosphate-glucuronosyltransferases (UGTs) involved in the glucuronide formation of efavirenz (EFV) and its three hydroxy metabolites, 8-hydroxyefavirenz (8-OH EFV), 7-hydroxyefavirenz (7-OH EFV), and 8,14-dihydroxyefavirenz (8,14-diOH EFV), were assessed. Among 12 recombinant UGT isoforms tested, only UGT2B7 showed catalytic activity in the formation of EFV-N-glucuronide (EFV-G) as previously reported. On the other hand, almost all UGT isoforms were involved in the glucuronidation of the three hydroxy metabolites, although their relative contribution is unclear. The catalytic activities in the formation of EFV-G by 17 different human liver microsomes exhibit a more than 40-fold inter-individual variability, whereas those of glucuronidation of the three hydroxy metabolites showed almost identical activity. The formation of EFV-G showed a significant correlation (r = 0.920; p < 0.0001) with UGT2B7-catalysed azidothymidine glucuronidation in 17 different human liver microsomes. Furthermore, fluconazole, a known UGT2B7 inhibitor, potently inhibited the formation of EFV-G up to 80%. This suggests that EFV might be a specific UGT2B7 substrate in vitro. This is the first study identifying specific UGT isozymes that glucuronidate EFV and its three hydroxy metabolites. Continued identification and characterisation of these pathways may help reduce adverse effects such as CNS toxicity in EFV therapy.


Assuntos
Benzoxazinas/metabolismo , Glucuronosiltransferase/metabolismo , Inibidores da Transcriptase Reversa/metabolismo , Alcinos , Ciclopropanos , Ácido Glucurônico/metabolismo , Humanos , Microssomos Hepáticos/metabolismo
15.
J Clin Endocrinol Metab ; 96(3): 799-807, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21190980

RESUMO

OBJECTIVE: Visceral fat is believed to be important in the pathogenesis of metabolic syndrome and fatty liver. In this study, we examined the relationship between mesenteric fat thickness and other sonographic indices of adiposity and the presence of fatty liver among subjects with polycystic ovary syndrome (PCOS). SUBJECTS AND METHODS: A total of 117 Chinese subjects with PCOS were evaluated (mean age, 28.6 ± 6.5 yr; mean body mass index, 24.3 ± 5.3 kg/m(2)). Anthropometric measurements and metabolic risk profile, including a standard oral glucose tolerance test, were assessed in all subjects. All subjects underwent an ultrasound examination for measurement of thickness of mesenteric, preperitoneal, and sc fat as well as evaluation for fatty liver. RESULTS: Forty-six (39.3%) of the subjects had fatty liver. PCOS subjects with fatty liver had higher body mass index, waist circumference, waist-hip ratio, and systolic blood pressure; a more unfavorable lipid profile with higher triglyceride; lower high-density lipoprotein cholesterol; higher fasting glucose and insulin; higher 2-h glucose during oral glucose tolerance test; lower SHBG; and higher alanine aminotransferase. Subjects with fatty liver had increased thickness of preperitoneal, mesenteric, and sc fat, as well as increased carotid intima-media thickness. Abdominal fat thickness showed moderate correlation to alanine aminotransferase as well as fasting insulin. On multivariate logistic regression, fasting insulin and mesenteric fat thickness were identified as independent predictors of fatty liver among subjects with PCOS. CONCLUSION: Fatty liver is present in a significant proportion of Chinese patients with PCOS. Sonographic measurement of mesenteric fat is an independent determinant of fatty liver among subjects with PCOS and identifies subjects at increased cardiovascular risk.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/etiologia , Mesentério/diagnóstico por imagem , Síndrome do Ovário Policístico/complicações , Adulto , Antropometria , Contagem de Células Sanguíneas , Análise Química do Sangue , Feminino , Teste de Tolerância a Glucose , Humanos , Lipídeos/sangue , Testes de Função Hepática , Síndrome do Ovário Policístico/diagnóstico , Valor Preditivo dos Testes , Fatores de Risco , Gordura Subcutânea/anatomia & histologia , Ultrassonografia , Circunferência da Cintura , Relação Cintura-Quadril , Adulto Jovem
16.
J Phys Chem B ; 113(50): 16169-77, 2009 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-19928867

RESUMO

We present a protocol for simultaneous structural characterization of a confined fluid and the confining substrate, along with the extraction of site-site pair correlation functions of the liquid of interest. This is based on neutron diffraction experiments, exploiting where feasible the isotopic substitution technique, analyzed through numerical coarse graining calculations and atomistic simulations. All of the subtleties of the experimental procedure, the needed ancillary measurements, and the recipe for tailoring the numerical codes to the real experiment and sample are described in the case of water confined in MCM41-S-15. In particular the excluded volume effects and the relevance of liquid-substrate cross-correlation terms in the neutron cross section are quantitatively discussed. The results obtained for the microscopic structure of water evidence a non-homogeneous distribution of molecules within the pore, with the presence of water-substrate hydrogen bonds, and a strong distortion of the water-water radial distribution functions with respect to those of bulk water extending at least up to three hydration layers.


Assuntos
Dióxido de Silício/química , Água/química , Espectroscopia de Ressonância de Spin Eletrônica , Difração de Nêutrons , Silanos/química
17.
Xenobiotica ; 38(9): 1240-51, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18720283

RESUMO

Atorvastatin is a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor that is mainly metabolized by cytochrome P450 (CYP) 3A4. A recent study showed that the lipid-lowering effect of statins is affected by the CYP3A5 polymorphism. Therefore, it was investigated whether CYP3A5 contributes to the metabolism of atorvastatin. Two metabolites of atorvastatin, para- and ortho-hydroxyatorvastatin, were produced by human liver microsomes and human recombinant CYP3A enzymes, and the enzyme kinetic pattern exhibited substrate inhibition. The intrinsic clearance (CL(int)) rates of para- and ortho-hydroxyatorvastatin by CYP3A4 were 2.4- and 5.0-fold of the respective CL(int) rates of CYP3A5, indicating that CYP3A4 is the major P450 isoform responsible for atorvastatin metabolism. These results suggest that atorvastatin is preferentially metabolized by CYP3A4 rather than by CYP3A5, and thus the genetic CYP3A5 polymorphism might not be an important factor in the inter-individual variation of atorvastatin disposition and pharmacodynamics in human.


Assuntos
Citocromo P-450 CYP3A/metabolismo , Ácidos Heptanoicos/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/metabolismo , Microssomos Hepáticos/metabolismo , Pirróis/metabolismo , Atorvastatina , Humanos , Cinética , Estrutura Molecular , Proteínas Recombinantes/metabolismo
18.
Xenobiotica ; 38(9): 1165-76, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18609447

RESUMO

1. KR-62980 and its stereoisomer KR-63198 are novel and selective peroxisome proliferator-activated receptor gamma (PPAR gamma) modulators with activity profiles different from that of rosiglitazone. This study was performed to identify the major metabolic pathways for KR-62980 and KR-63198 in human liver microsomes. 2. Human liver microsomal incubation of KR-62980 and KR-63198 in the presence of a beta-nicotinamide adenine dinucleotide phosphate (NADPH)-generating system resulted in hydroxy metabolite formation. In addition, the specific cytochrome P450s (CYPs) responsible for KR-62980 and KR-63198 hydroxylation were identified by using a combination of chemical inhibition in human liver microsomes and metabolism by recombinant P450s. It is shown that CYP1A2, CYP2D6, CYP3A4, and CYP3A5 are the predominant enzymes in the hydroxylation of KR-62980 and KR-63198. 3. The intrinsic clearance through hydroxylation was consistently and significantly higher for KR-62980 than for KR-63198, indicating metabolic stereoselectivity (CL(int) of 0.012 +/- 0.001 versus 0.004 +/- 0.001 microl min(-1) pmol(-1) P450, respectively). 4. In a drug-drug interaction study, KR-62980 and KR-63198 had no effect on the activities of the P450s tested (IC(50) > 50 microM), suggesting that in clinical interactions between KR-62980 and KR-63198 the P450s tested would not be expected.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Indenos/metabolismo , Microssomos Hepáticos/metabolismo , Morfolinas/metabolismo , PPAR gama/agonistas , Inibidores das Enzimas do Citocromo P-450 , Humanos , Indenos/farmacologia , Cinética , Espectrometria de Massas , Estrutura Molecular , Morfolinas/farmacologia , Proteínas Recombinantes/metabolismo
19.
Xenobiotica ; 38(4): 422-34, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18340565

RESUMO

To evaluate the effects of dietary salt on the stereoselective disposition of verapamil enantiomers in relation to the transporter ABCB1 2677GG/3435CC and 2677TT/3435TT haplotypes, ten healthy subjects were asked to take diets of three different salt levels for 7 days in a randomized, three-way crossover manner. The plasma concentrations of verapamil and norverapamil enantiomers were determined after a single oral dose of 240 mg verapamil on the last day of each phase. Pharmacokinetic parameters were calculated by non-compartmental analysis techniques and compared among the three different dietary salt phases. Compared with the medium salt diet, the high and low salt diets had no significant effect on the disposition of verapamil enantiomers. Moreover, the ABCB1 haplotypes did not alter the impact of dietary salt, although ABCB1 2677TT/3435TT subjects had slightly, but not significantly, higher C(max) and area under the curve (AUC) and lower T(max) for the verapamil enantiomers than did 2677GG/3435CC subjects in each salt phase.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Bloqueadores dos Canais de Cálcio/farmacocinética , Polimorfismo Genético , Cloreto de Sódio na Dieta/farmacologia , Verapamil/farmacocinética , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Adulto , Bloqueadores dos Canais de Cálcio/química , Estudos Cross-Over , Haplótipos , Humanos , Coreia (Geográfico) , Masculino , Mutação Puntual , Estereoisomerismo , Verapamil/análogos & derivados , Verapamil/urina
20.
Clin Pharmacol Ther ; 82(5): 531-40, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17392720

RESUMO

To develop and validate an in vivo cocktail method for high-throughput phenotyping of CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A, 12 healthy subjects received five probe drugs alone or simultaneously. The in vivo phenotyping index of CYP2C9, the ratio of 8 h urine concentration of losartan to its metabolite after a single administration of losartan, was not significantly different from that obtained using the five-drug cocktail. Similarly, the ratios of [omeprazole]/[5-hydroxyomeprazole] (CYP2C19) and [paraxanthine]/[caffeine] (CYP1A2) in 4 h plasma samples and the log ratio of [dextromethorphan]/[dextrorphan] (CYP2D6) in 8 h urine samples and the 4 h plasma concentrations of midazolam (CYP3A) after single administration or well-established three-drug cocktail of caffeine, omeprazole, and dextromethorphan were not significantly different from those after the new five-drug cocktail. In conclusion, the new five-drug cocktail regimen, named the "Inje cocktail," can be used as a tool to phenotype in vivo enzyme activities of CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A with only 4 h blood sampling and 8 h urine collection following simultaneous administration of the five probe drugs.


Assuntos
Cafeína , Sistema Enzimático do Citocromo P-450/genética , Dextrometorfano , Losartan , Midazolam , Omeprazol , Fenótipo , Administração Oral , Adulto , Hidrocarboneto de Aril Hidroxilases/genética , Cafeína/administração & dosagem , Cafeína/sangue , Cafeína/urina , Estudos Cross-Over , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP2C19 , Citocromo P-450 CYP2C9 , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP3A/genética , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Dextrometorfano/administração & dosagem , Dextrometorfano/sangue , Dextrometorfano/urina , Interações Medicamentosas , Genótipo , Humanos , Isoenzimas/efeitos dos fármacos , Modelos Lineares , Losartan/administração & dosagem , Losartan/sangue , Losartan/urina , Masculino , Midazolam/administração & dosagem , Midazolam/sangue , Midazolam/urina , Oxigenases de Função Mista/genética , Omeprazol/administração & dosagem , Omeprazol/sangue , Omeprazol/urina , Reação em Cadeia da Polimerase , Valores de Referência , Fatores de Tempo
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