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1.
Int J Mol Sci ; 24(15)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37569547

RESUMO

Protein tyrosine kinase 7 (PTK7), a catalytically defective receptor tyrosine kinase (RTK), is often upregulated in various cancers. This study aimed to validate PTK7 as a target for breast cancer (BC) and investigate its oncogenic signaling mechanism. BC tissue analysis showed significantly elevated PTK7 mRNA levels, especially in refractory triple-negative breast cancer (TNBC) tissues, compared with normal controls. Similarly, BC cell lines exhibited increased PTK7 expression. Knockdown of PTK7 inhibited the proliferation of T-47D and MCF-7 hormone-receptor-positive BC cell-lines and of HCC1187, MDA-MB-231, MDA-MB-436, and MDA-MB-453 TNBC cells. PTK7 knockdown also inhibited the adhesion, migration, and invasion of MDA-MB-231, MDA-MB-436, and MDA-MB-453 cells, and reduced the phosphorylation levels of crucial oncogenic regulators including extracellular signal-regulated kinase (ERK), Akt, and focal adhesion kinase (FAK). Furthermore, PTK7 interacts with fibroblast growth factor receptor 1 (FGFR1) and epidermal growth factor receptor (EGFR) expressed in MDA-MB-231 cells. Knockdown of PTK7 decreased the growth-factor-induced phosphorylation of FGFR1 and EGFR in MDA-MB-231 cells, indicating its association with RTK activation. In conclusion, PTK7 plays a significant role in oncogenic signal transduction by enhancing FGFR1 and EGFR activation, influencing BC tumorigenesis and metastasis. Hence, PTK7 represents a potential candidate for targeted BC therapy, including TNBC.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Transdução de Sinais , Fosforilação , Receptores ErbB/genética , Receptores ErbB/metabolismo , Movimento Celular/genética , Proliferação de Células/genética , Moléculas de Adesão Celular/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo
2.
Int J Mol Sci ; 24(15)2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37569820

RESUMO

Leucine-rich alpha-2-glycoprotein 1 (LRG1) mediates skin repair and fibrosis by stimulating the transforming growth factor-beta (TGF-ß) signaling pathway. In the present study, we investigated the effect of LRG1 on extracellular matrix (ECM) integrity in fibroblasts, as well as on skin aging. The treatment of dermal fibroblasts with purified recombinant human LRG1 increased type I collagen secretion and decreased matrix metalloproteinase-1 secretion. Additionally, LRG1 promoted SMAD2/SMAD3 phosphorylation in a pattern similar to that of TGF-ß1 treatment. An inhibitor of TGF-ß receptor 1 abolished LRG1-induced SMAD2 phosphorylation. RNA sequencing identified "extracellular region", "extracellular space", and "extracellular matrix" as the main Gene Ontology terms in the differentially expressed genes of fibroblasts treated with or without LRG1. LRG1 increased TGF-ß1 mRNA levels, suggesting that LRG1 partially transactivates the expression of TGF-ß1. Furthermore, an increased expression of type I collagen was also observed in fibroblasts grown in three-dimensional cultures on a collagen gel mimicking the dermis. LRG1 mRNA and protein levels were significantly reduced in elderly human skin tissues with weakened ECM integrity compared to in young human skin tissues. Taken together, our results suggest that LRG1 could retard skin aging by activating the TGF-ß signaling pathway, increasing ECM deposition while decreasing its degradation.


Assuntos
Colágeno Tipo I , Fator de Crescimento Transformador beta1 , Humanos , Idoso , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Transdução de Sinais , Fibroblastos/metabolismo , RNA Mensageiro/metabolismo , Células Cultivadas , Glicoproteínas/metabolismo
3.
Exp Eye Res ; 220: 109091, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35487263

RESUMO

The visual system uses ON and OFF pathways to signal luminance increments and decrements. Increasing evidence suggests that ON and OFF pathways have different signaling properties and serve specialized visual functions. However, it is still unclear the contribution of ON and OFF pathways to visual behavior. Therefore, we examined the effects on optomotor response and the retinal dopamine system in nob mice with ON pathway dysfunction and Vsx1-/- mice with partial OFF pathway dysfunction. Spatial frequency and contrast sensitivity thresholds were determined, and values were compared to age-matched wild-type controls. Retinas were collected immediately after visual testing to measure levels of dopamine and its metabolite, DOPAC. At 4 weeks of age, we found that nob mice had significantly reduced spatial frequency (19%) and contrast sensitivity (60%) thresholds compared to wild-type mice. Vsx1-/- mice also exhibited reductions in optomotor responses (3% in spatial frequency; 18% in contrast sensitivity) at 4 weeks, although these changes were significantly smaller than those found in nob mice. Furthermore, nob mice had significantly lower DOPAC levels (53%) and dopamine turnover (41%) compared to controls while Vsx1-/- mice displayed a transient increase in DOPAC levels at 4 weeks of age (55%). Our results show that dysfunction of ON pathways leads to reductions in contrast sensitivity, spatial frequency threshold, and retinal dopamine turnover whereas partial loss of the OFF pathway has minimal effect. We conclude that ON pathways play a critical role in visual reflexes and retinal dopamine signaling, highlighting a potential association for future investigations.


Assuntos
Dopamina , Retina , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Dopamina/metabolismo , Proteínas do Olho , Proteínas de Homeodomínio/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Retina/metabolismo , Visão Ocular
4.
Invest Ophthalmol Vis Sci ; 62(1): 28, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33502461

RESUMO

Purpose: Exposure to high-intensity or outdoor lighting has been shown to decrease the severity of myopia in both human epidemiological studies and animal models. Currently, it is not fully understood how light interacts with visual signaling to impact myopia. Previous work performed in the mouse retina has demonstrated that functional rod photoreceptors are needed to develop experimentally-induced myopia, alluding to an essential role for rod signaling in refractive development. Methods: To determine whether dim rod-dominated illuminance levels influence myopia susceptibility, we housed male C57BL/6J mice under 12:12 light/dark cycles with scotopic (1.6 × 10-3 candela/m2), mesopic (1.6 × 101 cd/m2), or photopic (4.7 × 103 cd/m2) lighting from post-natal day 23 (P23) to P38. Half the mice received monocular exposure to -10 diopter (D) lens defocus from P28-38. Molecular assays to measure expression and content of DA-related genes and protein were conducted to determine how illuminance and lens defocus alter dopamine (DA) synthesis, storage, uptake, and degradation and affect myopia susceptibility in mice. Results: We found that mice exposed to either scotopic or photopic lighting developed significantly less severe myopic refractive shifts (lens treated eye minus contralateral eye; -1.62 ± 0.37D and -1.74 ± 0.44D, respectively) than mice exposed to mesopic lighting (-3.61 ± 0.50D; P < 0.005). The 3,4-dihydroxyphenylacetic acid /DA ratio, indicating DA activity, was highest under photopic light regardless of lens defocus treatment (controls: 0.09 ± 0.011 pg/mg, lens defocus: 0.08 ± 0.008 pg/mg). Conclusions: Lens defocus interacted with ambient conditions to differentially alter myopia susceptibility and DA-related genes and proteins. Collectively, these results show that scotopic and photopic lighting protect against lens-induced myopia, potentially indicating that a broad range of light levels are important in refractive development.


Assuntos
Visão de Cores/fisiologia , Dopamina/metabolismo , Luz , Visão Mesópica/fisiologia , Miopia/metabolismo , Visão Noturna/fisiologia , Retina/metabolismo , Animais , Western Blotting , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Regulação da Expressão Gênica/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monoaminoxidase/genética , Refração Ocular/fisiologia , Transdução de Sinais/fisiologia , Proteínas Vesiculares de Transporte de Monoamina/genética , Acuidade Visual/fisiologia
5.
Sci Justice ; 60(1): 86-94, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31924293

RESUMO

Over the past decade, illicit drugs have been founded in marketed products, which pose a risk to public health. In particular, newly designed analogues synthesized by chemical modification of parent compounds to avoid detection by authorities are frequently detected worldwide. Although many analytical methods for determination of drugs have been reported, analytical methods using high-resolution mass spectrometry, which has the advantage of rapid screening and accurate identification of new substances, are necessary to control illicit drugs in marketed products. In this study, a rapid analytical method using an Orbitrap™ mass spectrometer for identification of illicit drugs in marketed products was developed. The 32 drugs were classified as benzodiazepine-, synthetic cannabinoid-, amphetamine- and benzylpiperazine-type drugs according to their chemical structures, and from their fragmentation patterns in tandem mass spectrometry spectra of an established method. The method validation gave a limit of detection of 0.06-5.30 ng/mL and a limit of quantification of 0.18-16.50 ng/mL, high linearity (R2 > 0.994) and mean recoveries of spiked matrix-blank samples ranging from 83.7% to 117.1%. Approximately 71% of 21 samples collected over 3 years were found to individually contain one of four types of benzodiazepines or two different synthetic cannabinoids. In one case, levels as high as 827.2 mg/g were measured suggesting adulteration at high levels, which suggests that potential illicit products containing drugs should be regularly screened to protect public health.


Assuntos
Contaminação de Medicamentos , Drogas Ilícitas/análise , Medicamentos Sintéticos/análise , Espectrometria de Massas em Tandem/métodos , Anfetaminas/análise , Benzodiazepinas/análise , Canabinoides/análise , Humanos , Drogas Ilícitas/síntese química , Limite de Detecção , Piperazinas/análise , Medicamentos Sintéticos/síntese química
6.
Forensic Sci Int ; 303: 109932, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31473560

RESUMO

With the increasing prevalence of obesity, the use of counterfeit drugs for weight loss is widespread owing to their easy and rapid availability. Since counterfeit weight-loss drugs are not prepared under the rigorous standard of Good Manufacturing Practice (GMP), they pose a risk to public health and cause significant side effects. To counteract the risk posed by counterfeit drugs, we investigated counterfeit weight-loss drugs seized by the Incheon Customs Services using UHPLC-PDA. Five of 23 confiscated samples with distinctive pink-coloured coating contained levothyroxine, sennoside A and B, and phenolphthalein in amounts ranging from 0.03-132.40 mg/g. In addition, three unknown compounds in one of the adulterated samples containing phenolphthalein were structurally elucidated by several analytical techniques. Their accurate masses corresponded to molecular formula of C34H22O7, C34H20O6, and C20H12O3, respectively. These compounds were identified as impurities, possibly produced during the synthesis of phenolphthalein or by improper removal during purification. These impurities were detected for the first time in counterfeit drugs.


Assuntos
Fármacos Antiobesidade/química , Medicamentos Falsificados/química , Cromatografia Líquida de Alta Pressão , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular
7.
Sci Justice ; 59(4): 433-441, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31256815

RESUMO

Recently, adulterated supplements with phosphodiesterase-5 inhibitors (PDE-5i) have frequently observed. New synthetic analogues obtained from the chemical modification of parent compounds are frequently found in illicit products despite continuous efforts to inspect for these adulterants. A rapid and accurate method based on quadrupole-Orbitrap mass spectrometry was developed for simultaneously confirming and quantifying 85 PDE-5i and derived analogues present in illicit products for erectile dysfunction (ED). Common ions of PDE-5i according to their similar structures were proposed based on MS/MS fragmentations. These common ions could be an important diagnosis of their presence targets or new emerging analogues in supplements. Several validation parameters were employed, resulting in a limit of detection and quantification of 0.09-8.55 ng/mL and 0.24-17.10 ng/mL, respectively. The linear correlation coefficient (r2) was higher than 0.995, and mean recoveries of target compounds were in the range of 82-118%. A total of 187 illicit products, obtained from on/offline markets over a period of 3 years (2015-2017), were screened by the established method. Approximately 53% of them were adulterated with PDE-5i or derived analogues at concentrations of 0.1-726.0 mg/g in the illicit products. In the interests of public health, this study describes a rapid and accurate method to determine PDE-5i and new emerging analogues in adulterated products.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos Falsificados , Espectrometria de Massas/métodos , Inibidores da Fosfodiesterase 5/química , Vasodilatadores/química , Suplementos Nutricionais , Contaminação de Medicamentos , Contaminação de Alimentos , Citrato de Sildenafila/análogos & derivados , Tadalafila/análogos & derivados , Dicloridrato de Vardenafila/análogos & derivados
8.
Forensic Sci Int ; 298: 10-19, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30870700

RESUMO

The worldwide spread of illegal sexual enhancement products is posing a threat to public health. The aim of this study was to investigate illegal products claiming to be effective in improving sexual performance through the online or offline markets between 2014 and 2017; these products include foods, dietary supplements, counterfeit drugs, and herbal medicines. These samples were analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the presence of 80 PDE-5 inhibitors (PDE-5i) and analogues. The developed method was validated as follows: LODs and LOQs spiked in solid- and liquid-type negative samples (0.03-3.33 ng/mL and 0.08-10.00 ng/mL), linearities (R2 > 0.997), recoveries spiked negative samples (82.2-109.3 %), accuracies (81.6-118.9 %), precisions (≥ 6.5%, RSD) of intra-day and inter-day, and stability (≥10.0%, RSD). Out of 362 measured samples, 145 were adulterated samples mostly detected in food (51%). Sildenafil group (50%) was frequently observed, followed by tadalafil group (41%). Although sildenafil and tadalafil were mainly detected in adulterated samples, their analogues were also found. In particular, new analogues have appeared steadily on illicit erectile dysfunction (ED) products even after they were first discovered. The concentration of detected samples ranged from 0.1 to 826.0 mg/g, and sildenafil of them contained a considerable amount in illicit ED products in 2014, posing a potential toxicology risk of public health. The testing method is fast and reliable making it suitable for both routine screening and up-to-date quantitative analysis of PDE-5i and their analogues in suspicious foods, dietary supplements, and counterfeit drugs.


Assuntos
Comércio , Medicamentos Falsificados , Inibidores da Fosfodiesterase 5/análise , Cromatografia Líquida , Suplementos Nutricionais , Formas de Dosagem , Contaminação de Alimentos/análise , Humanos , Internet , Limite de Detecção , Espectrometria de Massas , Inibidores da Fosfodiesterase 5/química , Fitoterapia
9.
Exp Eye Res ; 180: 226-230, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30605665

RESUMO

Retinal photoreceptors are important in visual signaling for normal eye growth in animals. We used Gnat2cplf3/cplf3 (Gnat2-/-) mice, a genetic mouse model of cone dysfunction to investigate the influence of cone signaling in ocular refractive development and myopia susceptibility in mice. Refractive development under normal visual conditions was measured for Gnat2-/- and age-matched Gnat2+/+ mice, every 2 weeks from 4 to 14 weeks of age. Weekly measurements were performed on a separate cohort of mice that underwent monocular form-deprivation (FD) in the right eye from 4 weeks of age using head-mounted diffusers. Refraction, corneal curvature, and ocular biometrics were obtained using photorefraction, keratometry and optical coherence tomography, respectively. Retinas from FD mice were harvested, and analyzed for dopamine (DA) and 3,4-dihydroxyphenylacetate (DOPAC) using high-performance liquid chromatography. Under normal visual conditions, Gnat2+/+ and Gnat2-/- mice showed similar refractive error, axial length, and corneal radii across development (p > 0.05), indicating no significant effects of the Gnat2 mutation on normal ocular refractive development in mice. Three weeks of FD produced a significantly greater myopic shift in Gnat2-/- mice compared to Gnat2+/+ controls (-5.40 ±â€¯1.33 D vs -2.28 ±â€¯0.28 D, p = 0.042). Neither the Gnat2 mutation nor FD altered retinal levels of DA or DOPAC. Our results indicate that cone pathways needed for high acuity vision in primates are not as critical for normal refractive development in mice, and that both rods and cones contribute to visual signalling pathways needed to respond to FD in mammalian eyes.


Assuntos
Miopia/fisiopatologia , Retina/fisiopatologia , Células Fotorreceptoras Retinianas Cones/patologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Suscetibilidade a Doenças , Dopamina/metabolismo , Feminino , Proteínas Heterotriméricas de Ligação ao GTP/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miopia/metabolismo , Refração Ocular/fisiologia , Retina/metabolismo , Privação Sensorial , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
10.
Sci Justice ; 58(6): 447-454, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30446074

RESUMO

A new sildenafil analogue was detected during routine screening of dietary supplements suspected to be adulterated with an erectile dysfunction drug(s) using HPLC-DAD. The UV spectrum of this compound was highly similar to that of sildenafil and almost identical to that of desmethylpiperazinyl sildenafil. The analogue was purified by using semi-preparative HPLC and structurally elucidated by performing mass spectrometric and NMR spectroscopic experiments. The spectral data revealed that this sildenafil analogue bears an n-propoxy group instead of an ethoxy group and possesses no methylpiperazinyl moiety. The isolated compound, structure of which was further confirmed by spectral comparison with synthetic one, was thus named as desmethylpiperazinyl propoxysildenafil.


Assuntos
Suplementos Nutricionais/análise , Citrato de Sildenafila/análogos & derivados , Cromatografia Líquida de Alta Pressão , Contaminação de Medicamentos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Espectrofotometria Infravermelho
11.
Forensic Sci Int ; 291: 167-174, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30216842

RESUMO

Illicit psychoactive substances have threatened public health worldwide. An active metabolite of ADB-CHMINACA and MDMB-CHMINACA was identified for the first time in a powder-type product found in an airmail package. The structure of compound 1 was elucidated by a combination of gas chromatography-mass spectrometry (GC-MS), liquid chromatography-high resolution mass spectrometry (LC-HRMS), infrared (IR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. Compound 1 was proven to be an analogue of MDMB-CHMINACA, an indazole-based synthetic cannabinoid. The methyl ester group in MDMB-CHMINACA was replaced with a carboxylic acid group in compound 1. Compound 1 was determined as 2-[1-(cyclohexylmethyl)-1H-indazole-3-carboxamido]-3,3-dimethylbutanoic acid and named as DMBA-CHMINACA.


Assuntos
Canabinoides/química , Drogas Ilícitas/química , Indazóis/química , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Estrutura Molecular , Análise Espectral
12.
Forensic Sci Int ; 284: 129-135, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29408720

RESUMO

Synthetic hair-growth compounds have been illegally used in diverse products to enhance the short-term efficacy of these products. In this study, a rapid and simultaneous method for the determination of hair-growth compounds in adulterated products based on ultra high pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was developed and validated. The limit of detection (LOD) and limit of quantitation (LOQs) of the method were 0.08-43.6ng/mL and 0.27-145ng/mL for the solid-, liquid-, and cream-type samples, respectively. Good calibration linearity for all compounds was demonstrated with a correlation coefficient (r2) higher than 0.997. The intra- and inter-assay precisions were within 11%. The corresponding accuracies were 86-117% and 81-113%, respectively. The mean recoveries obtained for the solid-, liquid, and cream-type samples ranged from 87 to 114%, with a relative standard deviation (RSD) within 6%. The RSD of the stability evaluated at 4°C for 48h was less than 6%. The established method was used to screen 76 samples advertised as hair-growth treatments, from online and offline markets, over the course of two years. In 10% of the samples, four compounds, including triaminodil, minoxidil, finasteride, methyltestosterone, and testosterone-propionate were detected. The concentrations were in the range of 0.5-16.4mg/g. This technique provides a reliable platform for technical analysis for continuous monitoring of adulterated products to protect public health.


Assuntos
Qualidade de Produtos para o Consumidor , Contaminação de Medicamentos , Preparações para Cabelo/química , Cromatografia Líquida de Alta Pressão , Finasterida/análise , Humanos , Limite de Detecção , Metiltestosterona/análise , Minoxidil/análogos & derivados , Minoxidil/análise , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Propionato de Testosterona/análise
13.
PLoS One ; 13(2): e0192435, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29408880

RESUMO

Visual experience during the critical period modulates visual development such that deprivation causes visual impairments while stimulation induces enhancements. This study aimed to determine whether visual stimulation in the form of daily optomotor response (OMR) testing during the mouse critical period (1) improves aspects of visual function, (2) involves retinal mechanisms and (3) is mediated by brain derived neurotrophic factor (BDNF) and dopamine (DA) signaling pathways. We tested spatial frequency thresholds in C57BL/6J mice daily from postnatal days 16 to 23 (P16 to P23) using OMR testing. Daily OMR-treated mice were compared to littermate controls that were placed in the OMR chamber without moving gratings. Contrast sensitivity thresholds, electroretinograms (ERGs), visual evoked potentials, and pattern ERGs were acquired at P21. To determine the role of BDNF signaling, a TrkB receptor antagonist (ANA-12) was systemically injected 2 hours prior to OMR testing in another cohort of mice. BDNF immunohistochemistry was performed on retina and brain sections. Retinal DA levels were measured using high-performance liquid chromatography. Daily OMR testing enhanced spatial frequency thresholds and contrast sensitivity compared to controls. OMR-treated mice also had improved rod-driven ERG oscillatory potential response times, greater BDNF immunoreactivity in the retinal ganglion cell layer, and increased retinal DA content compared to controls. VEPs and pattern ERGs were unchanged. Systemic delivery of ANA-12 attenuated OMR-induced visual enhancements. Daily OMR testing during the critical period leads to general visual function improvements accompanied by increased DA and BDNF in the retina, with this process being requisitely mediated by TrkB activation. These results suggest that novel combination therapies involving visual stimulation and using both behavioral and molecular approaches may benefit degenerative retinal diseases or amblyopia.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Estimulação Luminosa , Retina/metabolismo , Acuidade Visual , Animais , Cromatografia Líquida de Alta Pressão , Sensibilidades de Contraste , Dopamina/metabolismo , Eletrorretinografia , Potenciais Evocados Visuais , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
14.
Artigo em Inglês | MEDLINE | ID: mdl-28612683

RESUMO

The purpose of this study was to validate a rapid, simple and accurate method using ultra-performance liquid chromatography (UPLC) for the simultaneous determination of 26 anti-diabetic compounds in illegally adulterated dietary supplements. The method was validated for specificity, linearity, limit of detection, limit of quantitation, precision, accuracy, recovery and stability. All compounds were separated with a resolution of over 1.5. The limits of detection and quantitation were 0.10-1.70 and 0.30-5.10 µg g-1 in a solid sample, respectively; the corresponding values were 0.10-1.25 and 0.30-3.75 µg ml-1 in a liquid sample. The correlation coefficient was > 0.99, precisions were 0.11-3.30% (intra-day) and 0.05-6.15% (inter-day), and accuracies were 83-108% (intra-day) and 85-109% (inter-day). The recoveries were measured with six dosage forms, and the results were acceptable as 87-117% with relative standard deviations ≤ 6.44%. The relative standard deviations of stability were ≤ 3.40% and the standard solution was stable for 48 h. Ninety-six samples were obtained from on/off-line markets and were analysed using the developed method. Among these samples, pioglitazone and glibenclamide were found in seven samples and the concentrations of each compound were 0.15% and 0.26-0.51%, respectively. With the increasing adulteration of dietary supplements with anti-diabetic drugs, this method may be helpful to protect public health and safety.


Assuntos
Suplementos Nutricionais/análise , Hipoglicemiantes/análise , Cromatografia Líquida de Alta Pressão , Contaminação de Medicamentos , Reprodutibilidade dos Testes
15.
Artigo em Inglês | MEDLINE | ID: mdl-29143575

RESUMO

In this study, we developed a UPLC-PDA and LC-Q-TOF/MS method to identify and measure the following prohibited substances that may be found in dietary supplements:triaminodil, minoxidil, bimatoprost, alimemazine, diphenylcyclopropenone, α-tradiol, finasteride, methyltestosterone, spironolatone, flutamide, cyproterone, dutasteride, and testosterone 17-propionate.The method was validated according to International Conference on Harmonization guidelines in terms of specificity, linearity, accuracy, precision, LOD, LOQ, recovery, and stability. The method was completely validated showing satisfactory data for all method validation parameters. The linearity was good (R2 > 0.999) with intra- and inter-day precision values of 0.2-3.4% and 0.3-2.9%, respectively. Moreover, the intra- and inter-day accuracies were 87-102% and 86-103%, respectively, and the precision was better than 9.4% (relative standard deviation).Hence, the proposed method is precise and has high quality,and can be utilised to comprehensively and continually monitor illegal drug adulteration in various forms of dietary supplements. Furthermore, to evaluate the applicability of the proposed method, we analysed 13 hair-growth compounds in 78 samples including food and dietary supplements. Minoxidil and triaminodil were detected in capsules at concentrations of 4.69 mg/g and 6.54 mg/g. In addition, finasteride was detected in a tablet at 13.45 mg/g. In addition, the major characteristic fragment ions were confirmed once again using LC-Q-TOF/MS for higher accuracy.


Assuntos
Suplementos Nutricionais/análise , Contaminação de Medicamentos , Contaminação de Alimentos/análise , Cabelo/efeitos dos fármacos , Cabelo/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Finasterida/análise , Minoxidil/análise , Espectrometria de Massas em Tandem
16.
Artigo em Inglês | MEDLINE | ID: mdl-29067865

RESUMO

A new minoxidil analogue was detected in an illegal dietary supplement advertised as a hair-growth treatment. The analogue was identified using ultra-performance liquid chromatography (UPLC), high-resolution mass spectrometry (LC-HR-MS) and nuclear magnetic resonance (NMR) spectroscopy. The compound was structurally elucidated as a minoxidil analogue in which the piperidinyl group of minoxidil was replaced with a pyrrolidinyl group corresponding to a molecular formula of C8H13N5O. The new analogue has been named triaminodil. As this is the first report of the compound, there are no chemical, toxicology or pharmacological data available.


Assuntos
Suplementos Nutricionais/análise , Contaminação de Medicamentos , Minoxidil/análogos & derivados , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Minoxidil/química , Estrutura Molecular
17.
J Sep Sci ; 40(24): 4677-4688, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29057572

RESUMO

Adulterated products are continuously detected in society and cause problems. In this study, we developed and validated a method for determining synthetic sedative-hypnotics and sleep inducers, including barbital, benzodiazepam, zolpidem, and first-generation antihistamines, in adulterated products using Quadrupole-Orbitrap mass spectrometry and ultrahigh performance liquid chromatography with tandem mass spectrometry. In Quadrupole-Orbitrap mass spectrometry analysis, target compounds were confirmed using a combination of retention time, mass tolerance, mass accuracy, and fragment ions. For quantification, several validation parameters were employed using ultrahigh performance liquid chromatography with tandem mass spectrometry. The limit of detection and limit of quantitation was 0.05-53 and 0.17-177 ng/mL, respectively. The correlation coefficient for linearity was more than 0.995. The intra- and interassay accuracies were 86-110 and 84-111%, respectively. Their precision values were evaluated as within 4.0 (intraday) and 10.7% (interday). Mean recoveries of target compounds in adulterated products ranged from 85 to 116%. The relative standard deviation of stability was less than 10.7% at 4°C for 48 h. The 144 adulterated products obtained over 3 years (2014-2016) from online and in-person vendors were tested using established methods. After rapidly screening with Quadrupole-Orbitrap mass spectrometry, the detected samples were quantified using ultrahigh performance liquid chromatography with tandem mass spectrometry. Two of them were adulterated with phenobarbital.


Assuntos
Contaminação de Medicamentos , Hipnóticos e Sedativos/análise , Medicamentos Indutores do Sono/análise , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Espectrometria de Massas em Tandem
18.
Artigo em Inglês | MEDLINE | ID: mdl-28004593

RESUMO

A new tadalafil analogue was found in a commercial dietary supplement for enhancing sexual performance. The compound was detected by a high-performance liquid chromatography-diode array detector (HPLC-DAD). The analogue was isolated using semi-preparative HPLC, and its accurate mass was established by two LC-high-resolution-mass spectrometers (LC-HRMS). The structure was determined by nuclear magnetic resonance (NMR) spectroscopy. The accurate mass of the compound corresponded to a molecular formula of C24H23N3O4. The compound was identified as a structural analogue of tadalafil in which the N-methyl group of tadalafil was replaced with an N-isopropyl group. We have named the new analogue isopropylnortadalafil and it is first reported herein.


Assuntos
Suplementos Nutricionais/análise , Tadalafila/análogos & derivados , Tadalafila/análise , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Tadalafila/química
19.
Optom Vis Sci ; 94(3): 387-394, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28005683

RESUMO

PURPOSE: To determine the association between changes in body length with ocular refraction, corneal radii, axial length, and lens thickness in two different mouse strains. METHODS: Body length, ocular refraction, corneal radii, axial length, and lens thickness were measured for two inbred mouse strains: 129S1/SvJ (n = 7) and C57BL/6 J (n = 10) from 4 to 12 weeks of age. Body length, from tip of nose to base of tail, was obtained using a digital camera. Biometric parameters, corneal radii, and refractions were measured using spectral-domain optical coherence tomography, automated keratometry, and infrared photorefraction, respectively. A mixed-model ANOVA was performed to examine the changes in ocular parameters as a function of body length and strain in mice controlling for age, gender, and weight over time. RESULTS: C57BL/6J mice had significantly longer body length (average body length at 10 weeks, 8.60 ± 0.06 cm) compared to 129S1/SvJ mice (8.31 ± 0.05 cm) during development (P < .001). C57BL/6J mice had significantly hyperopic refractions compared to 129S1/SvJ mice across age (mean refraction at 10 weeks, 129S1/SvJ: +0.99 ± 0.44D vs. C57BL/6J: +6.24 ± 0.38D, P < .001). Corneal radius of curvature, axial length, and lens thickness (except 10 weeks lens thickness) were similar between the two strains throughout the measurement. In the mixed-model ANOVA, changes in body length showed an independent and significant association with the changes in refraction (P = .002) and corneal radii (P = .016) for each mouse strain. No significant association was found between the changes in axial length (P = .925) or lens thickness (P = .973) as a function of body length and strain. CONCLUSIONS: Changes in body length are significantly associated with the changes in ocular refraction and corneal radii in different mouse strains. Future studies are needed to determine if the association between body length and ocular refraction are related to changes in corneal curvature in mice.


Assuntos
Comprimento Axial do Olho/fisiologia , Tamanho Corporal/fisiologia , Córnea/anatomia & histologia , Cristalino/anatomia & histologia , Refração Ocular/fisiologia , Erros de Refração/fisiopatologia , Animais , Biometria/métodos , Feminino , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Tomografia de Coerência Óptica
20.
Invest Ophthalmol Vis Sci ; 57(14): 6089-6097, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27832275

RESUMO

PURPOSE: MicroRNA (miRNAs) have been previously implicated in scleral remodeling in normal eye growth. They have the potential to be therapeutic targets for prevention/retardation of exaggerated eye growth in myopia by modulating scleral matrix remodeling. To explore this potential, genome-wide miRNA and messenger RNA (mRNA) scleral profiles in myopic and control eyes from mice were studied. METHODS: C57BL/6J mice (n = 7; P28) reared under a 12L:12D cycle were form-deprived (FD) unilaterally for 2 weeks. Refractive error and axial length changes were measured using photorefraction and 1310-nm spectral-domain optical coherence tomography, respectively. Scleral RNA samples from FD and fellow control eyes were processed for microarray assay. Statistical analyses were performed using National Institute of Aging array analysis tool; group comparisons were made using ANOVA, and gene ontologies were identified using software available on the Web. Findings were confirmed using quantitative PCR in a separate group of mice (n = 7). RESULTS: Form-deprived eyes showed myopic shifts in refractive error (-2.02 ± 0.47 D; P < 0.01). Comparison of the scleral RNA profiles of test eyes with those of control eyes revealed 54 differentially expressed miRNAs and 261 mRNAs fold-change >1.25 (maximum fold change = 1.63 and 2.7 for miRNAs and mRNAs, respectively) (P < 0.05; minimum, P = 0.0001). Significant ontologies showing gene over-representation (P < 0.05) included intermediate filament organization, scaffold protein binding, detection of stimuli, calcium ion, G protein, and phototransduction. Significant differential expression of Let-7a and miR-16-2, and Smok4a, Prph2, and Gnat1 were confirmed. CONCLUSIONS: Scleral mi- and mRNAs showed differential expression linked to myopia, supporting the involvement of miRNAs in eye growth regulation. The observed general trend of relatively small fold-changes suggests a tightly controlled, regulatory mechanism for scleral gene expression.


Assuntos
Regulação da Expressão Gênica , MicroRNAs/genética , Miopia/genética , RNA Mensageiro/genética , Refração Ocular , Esclera/metabolismo , Animais , Modelos Animais de Doenças , Estudo de Associação Genômica Ampla , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/biossíntese , Miopia/metabolismo , Miopia/fisiopatologia , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase em Tempo Real , Esclera/patologia , Privação Sensorial , Tomografia de Coerência Óptica
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