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1.
Br J Nutr ; 129(5): 771-778, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35272722

RESUMO

Extracts of mulberry have been shown to reduce post-prandial glucose (PPG) and insulin (PPI) responses, but reliability of these effects and required doses and specifications are unclear. We previously found that 1·5 g of a specified mulberry fruit extract (MFE) significantly reduced PPG and PPI responses to 50 g carbohydrate as rice porridge, with no indications of intolerance. The trials reported here aimed to replicate that work and assess the efficacy of lower MFE doses, using boiled rice as the carbohydrate source. Two separate randomised controlled intervention studies were carried out with healthy Indian males and females aged 20-50 years (n 84 per trial), with PPG area under the curve over 2 h as the primary outcome. Trial 1 used doses of 0, 0·37, 0·75, 1·12 and 1·5 g MFE in boiled rice and 0 or 1·5 g MFE in rice porridge. Trial 2 used doses of 0, 0·04, 0·12, 0·37 g MFE in boiled rice. In trial 1, relative to control, all MFE doses significantly decreased PPG (-27·2 to -22·9 %; all P ≤ 0·02) and PPI (-34·6 to -14·0 %, all P < 0·01). Breath hydrogen was significantly increased only at 1·5 g MFE (in rice porridge), and self-reported gastrointestinal symptoms were uniformly low. In trial 2, only 0·37 g MFE significantly affected PPG (-20·4 %, P = 0·002) and PPI (-17·0 %, P < 0·001). Together, these trials show that MFE in doses as low as 0·37 g can reliably reduce PPG and PPI responses to a carbohydrate-rich meal, with no apparent adverse effects.


Assuntos
Insulina , Morus , Masculino , Feminino , Humanos , Adulto , Glicemia , Frutas , Reprodutibilidade dos Testes , Glucose , Extratos Vegetais/farmacologia , Período Pós-Prandial
2.
Liver Int ; 42(10): 2167-2174, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35758891

RESUMO

BACKGROUND AND AIMS: In vitro fertilization-embryo transfer (IVF-ET) may increase the risk of mother-to-child transmission (MTCT) of hepatitis B virus (HBV). The purpose of this study was to investigate the impact and safety of IVF-ET on MTCT in women with chronic HBV infection (CHB). METHODS: The data of 298 women who got pregnant by IVF-ET and their 375 children were collected retrospectively. Mothers were divided into the CHB group (n = 224) and the control group (HBsAg negative, n = 74). After birth, newborns were routinely vaccinated with the hepatitis B vaccine, and infants in the CHB group were injected with hepatitis B immunoglobulin within 2 h after birth. Demographic information, clinical data and laboratory test results were collected. The primary outcome measures were the MTCT rate of HBV, and the secondary outcome measures were the safety of the mother and infant. RESULTS: There was no case of HBV MTCT in all 282 newborns born in the CHB group and 93 neonates born in the control group. Of the two groups, the birth weight (3056.74 ± 601.65 vs. 2926.24 ± 704.86, P = .083), length (49.22 ± 1.97 vs. 48.74 ± 3.09, P = .167), 5-min Apgar score (9.97 ± 0.21 vs. 9.90 ± 0.51, P = .212), days of pregnancy (265.70 ± 12.73 vs. 262.02 ± 17.50, P = .064) and neonatal malformation rate (0.71% vs. 0, P = 1.000) were similar. Two cases of neonatal malformation occurred in the CHB group. The incidences of pregnancy and childbirth complications were similar between the two groups. CONCLUSION: IVF-ET does not increase the risk of MTCT in women with chronic HBV infection, and it is safe for mothers and infants.


Assuntos
Hepatite B Crônica , Hepatite B , Complicações Infecciosas na Gravidez , DNA Viral , Transferência Embrionária , Feminino , Fertilização in vitro , Hepatite B/prevenção & controle , Antígenos de Superfície da Hepatite B , Vacinas contra Hepatite B , Vírus da Hepatite B/genética , Humanos , Lactente , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Mães , Gravidez , Estudos Retrospectivos
3.
Virulence ; 12(1): 1527-1537, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34120564

RESUMO

We prospectively investigated the neurological development in infants born from mothers treated with telbivudine (LdT) in the third trimester for prevention of hepatitis B virus (HBV) mother-to-infant transmission. Mothers with high HBV load were assigned to either the LdT group (n = 81, 600 mg of LdT each day from gestational week 28 to delivery) or the Control group (n = 39, untreated). Their infants were followed for 36 months to assess physical and neurological developments with Gesell Developmental Schedule tools. At 12 months after birth, the mean scores in the LdT group for gross motor, fine motor, adaptive, linguistic, and personal social domains were similar to those in the Control group. At 36 months, infants in the LdT group had higher mean scores for gross motor than the Control group (98.42 ± 9.69 vs. 94.54 ± 7.48, P = 0.03). In the LdT group, the rates of normal development were higher for gross motor (96.30% vs. 82.05% P = 0.01) and lower for adaptive (74.07% vs. 92.31% P = 0.02). Multivariate regression analyses showed that exposure to LdT during pregnancy was independently associated with infant's development in gross motor (OR 6.49, 95% CI 1.37-30.20, P = 0.02) and adaptive (OR 0.18, 95% CI 0.05-0.71, P = 0.01) at 36 months. These results suggest that prenatal LdT exposure might affect neurological development in long-term observation.Abbreviations: LdT: telbivudine; HBV: hepatitis B virus; HBsAg: hepatitis B surface antigen; HBeAg: hepatitis Be antigen; HbsAb: hepatitis B surface antibody; ALT: alanine aminotransferase; NA: nucleoside/nucleotide analog; LAM: lamivudine; MTCT: mother-to-child transmission; GDS: Gesell Developmental Schedule; OR: odds ratio; CI: confidence interval; DQ: developmental quotient; RMB: renminbi; BMI: body mass Index; HBIG: hepatitis B immunoglobulin.


Assuntos
Antivirais , Hepatite B Crônica , Transmissão Vertical de Doenças Infecciosas , Sistema Nervoso , Complicações Infecciosas na Gravidez , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Telbivudina/efeitos adversos , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Desenvolvimento Infantil , DNA Viral , Feminino , Seguimentos , Hepatite B Crônica/tratamento farmacológico , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Destreza Motora , Sistema Nervoso/efeitos dos fármacos , Sistema Nervoso/crescimento & desenvolvimento , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Estudos Prospectivos , Telbivudina/uso terapêutico , Resultado do Tratamento
4.
Nutr Metab (Lond) ; 17: 51, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32647531

RESUMO

BACKGROUND: Lower post-prandial glucose (PPG) and insulin (PPI) responses to foods are associated with reduced diabetes risk and progression. Several plant extracts have been proposed to reduce PPG or PPI by inhibiting enzymes or transporters involved in carbohydrate digestion and uptake. This study evaluates a range of such extracts, consumed with a carbohydrate load, for their effects on PPG, PPI and indicators of (gastrointestinal) tolerance. METHODS: Interventions were extracts of mulberry fruit (MFE, 1.5 g), mulberry leaf (MLE, 1.0 g), white bean (WBE, 3.0 g), apple (AE, 2.0 g), elderberry (EE, 2.0 g), turmeric (TE, 0.18 g), AE + TE, and EE + TE. Each of these 8 individual extracts or combinations were added to a rice porridge containing ~ 50 g available carbohydrate (control). In a within-subject (randomised, balanced incomplete block) design, individual subjects received the control and a subset of 4 of the 8 extracts or combinations. Participants were 72 apparently healthy adults (mean [SD] age 31.2 [5.5] yr, body mass index 22.1 [2.0] kg/m2). The primary outcome was the percentage change in 2-h PPG (positive incremental area under the curve) relative to control. Secondary measures were the 2-h PPI response, 7-h breath hydrogen, measures of gastrointestinal discomfort, and urine glucose. RESULTS: In the 65 subjects who completed the control and at least one intervention treatment, additions of AE, MFE and MLE produced statistically significant reductions in PPG vs control (p < 0.05; mean effect - 24.1 to - 38.1%). All extracts and combinations except TE and WBE significantly reduced PPI (p < 0.01; mean effect - 17.3% to - 30.4%). Rises in breath hydrogen > 10 ppm were infrequent, but statistically more frequent than control only for MLE (p = 0.02). Scores for gastrointestinal discomfort were extremely low and not different from control for any treatment, and no glucosuria was observed. CONCLUSIONS: Additions of AE, MFE and MLE to rice robustly reduced PPG and PPI. EE significantly reduced only PPI, while TE and WBE showed no significant efficacy for PPG or PPI. Breath hydrogen responses to MLE suggest possible carbohydrate malabsorption at the dose used, but there were no explicit indications of intolerance to any of the extracts. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT04258501. Registered 6 February 2020 - Retrospectively registered.

5.
J Biomater Sci Polym Ed ; 31(4): 549-560, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31902299

RESUMO

Eye drop solutions are widely used by the ophthalmologist to treat the anterior segment eye diseases. However, eye drop solutions have many limitations including low bioavailability, high dose requirements, and poor patient compliance. Contact lenses are used to deliver the ocular drugs with high ocular bioavailability due to its immediate location to cornea. To attend controlled and prolonged drug release from the contact lenses, scientists are working on various systems including polymeric nanoparticles, molecular imprinting, microemulsion, micelles, liposomes, implantation, supercritical fluids, and use of vitamin E. However, the changes in the critical lens properties like swelling, optical transparency, ion permeability, tensile strength, oxygen permeability, high burst release, issues during monomer extraction, sterilization and storage are yet to address. The review is focused on the commercial challenges with different methodologies to develop therapeutic contact lenses for commercial market. Many animal and clinical studies are under pipeline and it is likely that the therapeutic contact lenses will be commercialized in next few years.


Assuntos
Lentes de Contato , Sistemas de Liberação de Medicamentos/instrumentação , Animais , Humanos
6.
Biomed Res Int ; 2019: 6547019, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31886236

RESUMO

BACKGROUND: Metformin has been reported to decrease insulin resistance and is associated with a lower risk of pregnancy-induced hypertension and preeclampsia. It is widely accepted that the placenta plays a crucial role in the development of preeclampsia. Our aim is to explore the effect of metformin on preeclampsia. STUDY DESIGN: We examined control diet-fed (isocaloric diet) pregnant mice (CTRL group), pregnant mice fed a high-fat diet (HF group), and high-fat-diet-fed pregnant mice treated with metformin (HF-M group). The HF mice were fed a high-fat diet six weeks before pregnancy to establish a preeclampsia-like model; then, the group was randomly divided into a HF group and a HF-M group after pregnancy. Blood pressure, urine protein, pregnancy outcomes, protein expression, and histopathological changes in the placentas of all groups were examined and statistically analysed. RESULTS: We observed that metformin significantly improved high blood pressure, proteinuria, and foetal and placental weights in the HF-M group compared with the HF group. Metformin significantly improved placental labyrinth and foetal vascular development in preeclampsia. In addition, metformin effectively increased matrix metalloproteinase-2 (MMP-2) and vascular endothelial growth factor (VEGF) levels in the placenta. CONCLUSIONS: Our results suggest that metformin can improve preeclamptic symptoms and pregnancy outcomes.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Metformina/farmacologia , Pré-Eclâmpsia/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Metaloproteinase 2 da Matriz/sangue , Camundongos , Placenta/efeitos dos fármacos , Pré-Eclâmpsia/induzido quimicamente , Gravidez , Proteinúria , Fator A de Crescimento do Endotélio Vascular/sangue
7.
Oncol Lett ; 13(4): 2459-2464, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28454420

RESUMO

Aminoacylase 1 (ACY1) is important for regulating the proliferation of numerous types of cancer. However, the expression and mechanisms underlying the function of ACY1 in colorectal cancer remain unclear. In order to investigate the expression and function of ACY1 in colorectal cancer, tumor tissue and blood samples were collected for analysis from 132 patients diagnosed with colorectal cancer. Reverse transcription-quantitative polymerase chain reaction analysis and western blotting identified significantly increased expression of ACY1 mRNA in colorectal tumor tissue (P<0.05 vs. adjacent normal tissue) and notably increased ACY1 protein levels. This ACY1 mRNA expression was found to be positively correlated with tumor stage. In addition, plasma ACY1 concentration was increased in patients with colorectal cancer compared with healthy controls. Furthermore, in vitro knockdown of ACY1 in human colorectal cancer HT-29 cells was shown to inhibit proliferation and increase apoptosis. This effect was found to be associated with the activation of ERK1 and TGF-ß1 signaling. In conclusion, the results of the present study suggest that ACY1 promotes tumor progression, and thus may be a potential target for the diagnosis and treatment of colorectal cancer.

8.
Biomed Chromatogr ; 27(7): 910-5, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23526237

RESUMO

22-[N(-7-Nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-23,24-bisnor-5-cholen-3ß-ol (NBD-cholesterol), a fluorescent cholesterol analog, was an extragenous cholesterol tracer used to study cholesterol absorption and metabolism in cultured cells. In order to measure free intracellular cholesterol and its esters, a precise and sensitive method employing high-performance liquid chromatography/fluorescence detection (HPLC-FLD) was developed for the first time. Method validation showed a limit of detection at 30 ng/mL. The calibration curve was linear within the range of 0.0625-10.0 µg/mL (r(2) = 0.999). Accuracy and precision were highlighted by good recovery and low variations. Apart from NBD-cholesteryl oleate, two additional cellular metabolites of NBD-cholesterol, probably an isomer and an oxidation product, were determined in the lipid extracts of Caco-2 human colon adenocarcinoma cells according to mass spectrometry. In AC29 mouse malignant mesothelioma cells overexpressing acyl-CoA:cholesterol acyltransferase-1 (ACAT1) or ACAT2, only the oxidized metabolite was detected. Using the newly developed method, YIC-C8-434, a known ACAT inhibitor, was shown to inhibit ACAT activity in Caco-2 cells, as well as in AC29/ACAT1 or AC29/ACAT2 cells. In conclusion, the sensitive and specific HPLC-FLD method is a powerful tool for simultaneous quantification of intracellular NBD-cholesterol and its oleoyl-ester.


Assuntos
4-Cloro-7-nitrobenzofurazano/análogos & derivados , Colesterol/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Espaço Intracelular , Espectrometria de Fluorescência/métodos , 4-Cloro-7-nitrobenzofurazano/análise , 4-Cloro-7-nitrobenzofurazano/química , 4-Cloro-7-nitrobenzofurazano/metabolismo , Animais , Células CACO-2 , Linhagem Celular Tumoral , Colesterol/análise , Colesterol/química , Colesterol/metabolismo , Ésteres/análise , Ésteres/química , Ésteres/metabolismo , Humanos , Espaço Intracelular/química , Espaço Intracelular/metabolismo , Modelos Lineares , Espectrometria de Massas , Camundongos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Neurobiol Aging ; 31(12): 2069-79, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19131143

RESUMO

Epidemiological and experimental studies have correlated hyperhomocysteinemia to a range of neurodegenerative conditions, including Alzheimer's disease, stroke, and Parkinson's disease. Although homocysteine-induced apoptosis in neurons has been extensively studied, little information is available regarding the effect of homocysteine on microglia. In this report, we demonstrated that homocysteine promoted proliferation and up-regulated the expression of CD11b (a marker of microglial activation). Consistent with our in vitro results, a significant increase in the number of CD11b-positive microglia was also observed in brain sections of mice with hyperhomocysteinemia. Homocysteine promoted the activity of NAD(P)H oxidases, resulting in the generation of reactive oxygen species. Up-regulation of NAD(P)H oxidase activity by homocysteine appears to be due to its ability to induce the phosphorylation of p47phox through the p38 MAPK pathway. Furthermore, inhibition of reactive oxygen species significantly blocked cellular proliferation and activation in microglia. Since microglial proliferation and activation play an important role in the development of several neurodegenerative disorders, our results reveal a novel role of homocysteine in the pathogenesis of neurodegenerative diseases.


Assuntos
Proliferação de Células/efeitos dos fármacos , Homocisteína/toxicidade , Microglia/citologia , Microglia/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Células Cultivadas , Replicação do DNA/efeitos dos fármacos , Replicação do DNA/fisiologia , Homocisteína/metabolismo , Hiper-Homocisteinemia/enzimologia , Hiper-Homocisteinemia/metabolismo , Hiper-Homocisteinemia/patologia , Camundongos , Camundongos Endogâmicos BALB C , Microglia/enzimologia , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
10.
Endocrinology ; 150(1): 277-85, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18801901

RESUMO

Endoplasmic reticulum (ER) stress has been implicated in several neurodegenerative diseases. Although CCAAT/enhancer-binding protein homologous protein (CHOP) has been shown to play a critical role in ER stress, the precise apoptosis cascade downstream of CHOP is unknown. In this report, we investigated the mechanism of ER stress-mediated apoptosis as well as the action of IGF-I in PC-12 neuronal cells. Our results demonstrated that tribbles-related protein 3 (TRB3), which is a target gene of CHOP, was responsible for tunicamycin (an ER stress inducer)-induced apoptosis. TRB3 could promote dephosphorylation of Akt in PC-12 cells. IGF-I inhibited ER stress-induced apoptosis by restoring the phosphorylation level of Akt. Both wortmannin (a phosphatidylinositide 3-kinase inhibitor) and SB 212090 (a p38 MAPK inhibitor) suppressed the protective effect of IGF-I on ER stress-induced apoptosis. Interestingly, IGF-I attenuated ER stress-mediated expression of TRB3 but not CHOP. This action of IGF-I was abolished by SB 212090 but not by wortmannin. Immunoprecipitation analysis revealed that IGF-I promoted the phosphorylation of CHOP by activating p38 MAPK, probably leading to a decrease in the transcriptional activity of CHOP. The dephosphorylation of Akt resulted in increased expression of a proapoptotic protein, p53 up-regulated modulator of apoptosis (PUMA), in a forkhead box O3a-dependent manner. Knockdown of PUMA by short hairpin RNA attenuated ER stress-mediated apoptosis. Thus, our current study indicates that both TRB3 and PUMA are critical molecules in ER stress-induced apoptosis. IGF-I effectively protects PC-12 neuronal cells against ER stress-induced apoptosis through the phosphatidylinositide 3-kinase/Akt and p38 MAPK pathways.


Assuntos
Apoptose/fisiologia , Retículo Endoplasmático/fisiologia , Fator de Crescimento Insulin-Like I/farmacologia , Neurônios/fisiologia , Animais , Apoptose/efeitos dos fármacos , Proteínas de Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/genética , Primers do DNA , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Regulação para Baixo , Retículo Endoplasmático/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neurônios/citologia , Células PC12 , Feocromocitoma , Proteínas Serina-Treonina Quinases/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/genética , RNA Neoplásico/genética , Ratos , Proteínas Repressoras/efeitos dos fármacos , Proteínas Repressoras/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
J Mol Med (Berl) ; 87(1): 75-84, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18825355

RESUMO

Homocysteine is an intermediate in sulfur amino acid metabolism, which takes place mainly in the liver. Recent studies have shown that hyperhomocysteinemia in patients and murine models develop hepatic fibrosis. To define mechanisms underlying homocysteine-induced hepatic fibrosis, the effect of homocysteine on hepatic stellate cell (HSC) proliferation was examined. In the present study, homocysteine promoted proliferation in myofibroblastic HSCs. Homocysteine elicited a transient formation of reactive oxygen species (ROS). The initial ROS activated extracellular signal-regulated kinase and p38 mitogen-activated protein kinase, which were involved in the activation of NAD(P)H oxidases and the generation of more ROS. The activation of NAD(P)H oxidases resulted from upregulation of the expression of p22(phox) and the phosphorylation of p47(phox). The ROS derived from NAD(P)H oxidases activated the PI3K/Akt pathway, thus promoting cellular proliferation in HSCs. These findings provide a mechanistic explanation for the development and progression of hepatic fibrosis in hyperhomocysteinemia.


Assuntos
Proliferação de Células/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Homocisteína/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Homocisteína/sangue , Hiper-Homocisteinemia/sangue , Cirrose Hepática/sangue , Masculino , NADPH Oxidases/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
12.
Zhongguo Zhong Yao Za Zhi ; 33(11): 1291-4, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18831210

RESUMO

OBJECTIVE: To study the plasma protein binding rate of methyl protodioscin. METHOD: The ultrafiltration was employed to determine the plasma protein binding rate of methyl protodioscin. The plasma concentrations of methyl protodioscin were measured by HPLC-MS-MS. RESULT: The plasma protein binding rate of methyl protodioscin with rat plasma at the concentration of 20.0, 100 and 200 microg x mL(-1) were (94.6 +/- 0.16)%, (91.6 +/- 0.35)% and (86.10 +/- 0.60)%, respectively, while the plasma protein binding rate of methyl protodioscin with normal human plasma at the above concentrations were (82.11 +/- 5.12)%, (84.54 +/- 0.32)% and (88.52 +/- 1.02)%, respectively. CONCLUSION: The binding rate of methyl protodioscin with plasma protein is high.


Assuntos
Antineoplásicos/metabolismo , Proteínas Sanguíneas/metabolismo , Diosgenina/análogos & derivados , Saponinas/metabolismo , Animais , Calibragem , Cromatografia Líquida de Alta Pressão , Diosgenina/metabolismo , Feminino , Humanos , Masculino , Ligação Proteica , Ratos , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem , Ultrafiltração
13.
Biomed Chromatogr ; 22(4): 408-13, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18004744

RESUMO

A high performance liquid chromatography/tandem mass spectrometry assay was first developed and validated for the quantification of methyl protodioscin (MPD), a natural furostanol saponin with distinct antitumor activity, in rat plasma with 17alpha-ethinylestradiol as internal standard (IS). Methanol-mediated protein precipitation was employed for plasma sample pretreatment. The separation was achieved on a C(18) column (150 x 4.6 mm, i.d., 5 microm) by isocratic elution with methanol-water (72:28, v/v) as mobile phase at a flow rate of 1.0 mL/min. Ion acquisition was performed in selective reaction monitoring positive mode by monitoring the transition of m/z 1085.7 --> 1053.7 for MPD, and in selective ion monitoring negative mode by monitoring the deprotonated ion m/z 295.5 for IS. The assay was linear over the concentration range of 2.024-270.0 microg/mL with 2.024 microg/mL as the lower limit of quantification. It was specific, accurate, precise and reproducible with intra- and inter-run RSD <8.3% and RE between -11.5 and 12.8%. The assay was successfully applied to a preclinical pharmacokinetic study after an intravenous dose of 40 mg/kg MPD to rats.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Diosgenina/análogos & derivados , Saponinas/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Diosgenina/administração & dosagem , Diosgenina/sangue , Diosgenina/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Estrutura Molecular , Ratos , Reprodutibilidade dos Testes , Saponinas/administração & dosagem , Saponinas/farmacocinética
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