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1.
JSES Int ; 8(1): 99-103, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38312266

RESUMO

Background: In the realm of orthopedic surgery, frailty has been associated with higher rates of complications following total hip and total knee arthroplasties. Among various measures of frailty, the Six-Item Modified Frailty Index (MF-6) has recently gained popularity as a predictor for postoperative complications. The purpose of this study was to investigate MF-6 as a predictor for early postoperative complications in the elderly patient population following total shoulder arthroplasty (TSA). Methods: The authors queried the American College of Surgeons National Surgical Quality Improvement Program database for all patients who underwent TSA between 2015 and 2020. Patient demographics and comorbidities were compared between cohorts using bivariate logistic regression analysis. Multivariate logistic regression, adjusted for all significantly associated patient demographics and comorbidities, was used to identify associations between the MF-6 score and postoperative complications. Results: Of total, 9228 patients were included in this study: 8764 (95.0%) had MF-6 <3, and 464 (5.0%) patients had MF-6 ≥3. Multivariate analysis found MF-6 ≥3 to be independently associated with higher rates of urinary tract infection (odds ratio [OR]: 2.79, 95% confidence interval [CI]: 1.49-5.23; P = .001), blood transfusion (OR: 1.53, 95% CI: 1.01-2.32; P = .045), readmission (OR: 1.58, 95% CI: 1.06-2.35; P = .024), and non-home discharge (OR: 2.60, 95% CI: 2.08-3.25; P < .001). Conclusion: A high MF-6 score (≥3) in patients aged 65 and older is independently associated with higher rates of urinary tract infection, blood transfusion, readmission, and non-home discharge following TSA. The MF-6 score can be easily calculated preoperatively and may allow for better preoperative risk stratification.

2.
J Pharm Biomed Anal ; 227: 115283, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36780864

RESUMO

Ten POWER dietary supplements, chronologically called tabs, pills then caps, and advertised as 100% natural aphrodisiacs, were analyzed by 1H NMR from 2007 to 2022. They were all tainted by PDE-5 inhibitors. Eight different adulterants were identified (sildenafil (1), sildenafil analogues (6), and vardenafil analogue (1)). Their amounts ranged from 15 to 145 mg/capsule. Four supplements contained at least 100 mg/capsule of PDE-5 inhibitor or analogue, the maximal recommended dose of sildenafil. The nature of the adulterant has changed over time, probably to evade its detection by regulatory agencies routine screening tests. Despite several warnings and/or seizures from several European food and/or health authorities, the dietary supplement POWER is still on sale on the Internet, thus demonstrating the impossibility of controlling this market. Faced with this situation, the consumer should be better informed by establishing at the European level a public database of tainted dietary supplements on the model of that of the US Food and Drug Administration. It should indicate the product name, its photo, the adulterant name, and be easily accessible to everyone.


Assuntos
Suplementos Nutricionais , Inibidores da Fosfodiesterase 5 , Suplementos Nutricionais/análise , Contaminação de Medicamentos/prevenção & controle , Espectroscopia de Ressonância Magnética , Inibidores da Fosfodiesterase 5/farmacologia , Citrato de Sildenafila , Dicloridrato de Vardenafila , Humanos
3.
J Pharm Biomed Anal ; 223: 115161, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36402125

RESUMO

Due to their health benefits, including regulating blood sugar and lowering cholesterol, berberine food supplements (FS) are widely used by consumers. This study aims to evaluate the quality of such products by proposing a new analytical methodology based on low-field NMR. Eighteen berberine FS were analyzed with both conventional (500 MHz) and benchtop (60 MHz) NMR spectrometers. Three quantitative 60 MHz 1H NMR methodologies were performed to determine berberine contents that were compared to those obtained at 500 MHz considered as reference measurements. To make the recording time of the spectra acquired at low field compatible with the requirements of a routine control, the quantification was carried out using a calibration curve established under conditions of incomplete relaxation of BrB protons. This methodology, applied to a test sample of 15 mg of FS, allowed to accurately measure a minimum quantity of berberine of ≈ 10 mg/capsule or tablet in 15 min. Regarding the FS, their labels are often unclear and/or incomplete for the consumer. Moreover, only 56 % of the FS analyzed actually contain the claimed quantity of berberine. The amounts of active they supply per day are extremely variable with only 39 % of the FS delivering a sufficient dose to achieve a hypoglycemic or hypolipidemic effect (1000-1500 mg/day based on literature data). These results show that health authorities should institute much stricter control and regulation over the production, labeling and marketing of berberine-based FS.


Assuntos
Berberina , Prótons , Espectroscopia de Prótons por Ressonância Magnética , Imageamento por Ressonância Magnética , Suplementos Nutricionais
4.
J Pharm Biomed Anal ; 212: 114631, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35231794

RESUMO

Due to the numerous potential health benefits of Curcuma, turmeric dietary supplements (DS) are among the top selling products. To assess the quality of these formulations, thirty Curcuma DS along with five standard Curcuma rhizomes were analyzed with UHPLC-MS and 1H NMR. The chemometric treatment of the UHPLC-MS spectra showed a significant variability of their chemical composition that was confirmed by 1H NMR which allowed the absolute quantification of the Curcuma major bioactive components, i.e. curcuminoids (curcumin, demethoxycurcumin and bisdemethoxycurcumin), and turmerones (aryl-, α- and ß-) as well as piperine, a commonly associated curcumin bioavailability enhancer: respectively 3.5-556, 0-8.6, 0.18-8.1 mg/capsule or tablet. The comparison of the actual and claimed quantities of curcuminoids and piperine showed that 58% of the DS contained the expected amounts of actives.


Assuntos
Curcuma , Curcumina , Cromatografia Líquida , Curcuma/química , Curcumina/análise , Diarileptanoides , Suplementos Nutricionais/análise , Extratos Vegetais/química , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas em Tandem
5.
J Pharm Biomed Anal ; 191: 113482, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32898728

RESUMO

A sexual enhancer dietary supplement in pre-commercialization phase was analyzed. It contained the two phosphodiesterase-5 inhibitors (PDE-5i) sildenafil and methisosildenafil as major adulterants. Fourteen more sildenafil derivatives were detected and after isolation, their structures were elucidated thanks to NMR, high resolution and tandem mass spectrometry, and UV spectroscopy. Ten of them were never described. All these compounds are probably by-products of different reaction steps during the synthesis of the two PDE-5i that were not properly eliminated during the purification procedure. The total amount of sildenafil-related compounds was estimated at 68 mg per capsule, sildenafil and methisosildenafil accounting for 20 mg and 38 mg respectively.


Assuntos
Contaminação de Medicamentos , Inibidores da Fosfodiesterase 5 , Suplementos Nutricionais/análise , Citrato de Sildenafila , Espectrometria de Massas em Tandem
6.
Molecules ; 25(2)2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31941089

RESUMO

Red yeast rice dietary supplements (RYR DS) are largely sold in Western countries for their cholesterol-lowering/regulating effect due to monacolins, mainly monacolin K (MK), which is, in fact, lovastatin, the first statin drug on the market. 1H-NMR was used as an easy, rapid and accurate method to establish the chemical profiles of 31 RYR DS and to quantify their monacolin contents. Among all the 1H resonances of the monacolins found in RYR, only those of the ethylenic protons of the hexahydronaphthalenic ring at 5.84 and 5.56 ppm are suitable for quantification because they show no overlap with the matrix signals. The total content in monacolins per capsule or tablet determined in 28 DS (the content in 3 DS being below the limit of quantification of the method, ≈ 0.25 mg per unit dose) was close to that measured by UHPLC, as shown by the good linear correlation between the two sets of values (slope 1.00, y-intercept 0.113, r2 0.986). Thirteen of the 31 RYR DS analyzed (i.e., 42%) did not provide label information on the concentration of monacolins and only nine of the 18 formulations with an indication (i.e., 50%) actually contained the declared amount of monacolins.


Assuntos
Produtos Biológicos/análise , Suplementos Nutricionais/análise , Naftalenos/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Ressonância Magnética Nuclear Biomolecular
7.
J Pharm Biomed Anal ; 135: 31-49, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-27988395

RESUMO

The sildenafil analogue adulterant previously identified as a nitroso derivative (nitrosoprodenafil) in a dietary supplement (DS) marketed to increase sexual performance and sold in Europe in the early 2010s is the same as that found in the same type of DS available in Japan whose structure was established as a nitro derivative (mutaprodenafil or nitroprodenafil). Indeed, the compound isolated from the Man Power DS has identical UV, IR, NMR and MS spectroscopic characteristics and hydrolysis behavior than nitrosoprode-nafil. By revisiting its NMR assignments and MS and MS/MS data interpretation, it is demonstrated that the compound is actually a nitrothioimidazole-methisosildenafil hybrid, i.e. nitroprodenafil, whose structure is unequivocally confirmed by X-ray crystallography and synthesis experiments. Because the product is converted to methisosildenafil by hydrolysis, it is named nitropromethisosildenafil.


Assuntos
Suplementos Nutricionais/análise , Contaminação de Medicamentos , Espectroscopia de Ressonância Magnética/métodos , Inibidores da Fosfodiesterase 5/análise , Espectrometria de Massas em Tandem/métodos , Cristalografia por Raios X/métodos , Humanos , Hidrólise , Imidazóis/análise , Imidazóis/química , Masculino , Espectrometria de Massas/métodos , Inibidores da Fosfodiesterase 5/química , Piperazinas/análise , Piperazinas/química
8.
J Pharm Biomed Anal ; 124: 34-47, 2016 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-26928212

RESUMO

One hundred and sixty food supplements (FS) marketed for weight loss and mainly purchased on the Internet were analyzed. All the FS were claimed as 100% natural containing only natural compounds, plant extracts and/or vitamins and the presence of an active pharmaceutical ingredient (API) was never mentioned. (1)H NMR spectroscopy was used for detecting the presence of adulterants and for their identification and quantification. Mass spectrometry was used as a complementary method for supporting their identification. Among the 164 samples considered because capsules from 5 different blisters of the same FS were analyzed, 56% were tainted with six API. Forty three contained sibutramine as single adulterant (26%), 9 phenolphthalein (6%) and 23 a mixture of these API (14%) that were both withdrawn from the market several years ago because of toxicity concerns. Sildenafil was found in 12 samples, either as a single adulterant (n=5) or in combination with sibutramine (n=3), phenolphthalein (n=3) and both sibutramine and phenolphthalein (n=1). Fluoxetine was present in 4 formulations, alone (n=3) or in combination with sibutramine and orlistat (n=1). At last, lorcaserine was detected in one FS. The content of sibutramine per dosage unit was comprised between 0.1 and 22 mg and that of phenolphthalein between 0.05 and 56 mg. The study also highlights poor manufacturing practices as evidenced for instance by the variability of API in capsules from different blisters of the same box. This paper demonstrates the need for more effective quality control of weight loss FS and the efficiency of (1)H NMR spectroscopy for the detection of tainted FS.


Assuntos
Suplementos Nutricionais/análise , Medicina Herbária , Espectroscopia de Prótons por Ressonância Magnética/métodos , Espectrometria de Massas
9.
J Pharm Biomed Anal ; 102: 476-93, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25459948

RESUMO

One hundred and fifty dietary supplements (DS) marketed to increase sexual performance were analyzed. All these formulations were claimed to contain only natural compounds, plant extracts and/or vitamins. (1)H NMR spectroscopy was used for detecting the presence of adulterants and for their identification and quantification. Mass spectrometry was used as a complementary method for confirming the chemical structures. 61% of DS were adulterated with phosphodiesterase-5 inhibitors (PDE-5i) (27% with the PDE-5i medicines sildenafil, tadalafil and vardenafil, and 34% with their structurally modified analogues). Among them, 64% contained only one PDE-5i and 36% mixtures of two, three and even four. The amounts of PDE-5i medicines were higher than the maximum recommended dose in 25% of DS tainted with these drugs. Additional 5.5% DS included other drugs for the treatment of sexual dysfunction (yohimbine, flibanserin, phentolamine, dehydroepiandrosterone or testosterone). Some DS (2.5%) contained products (osthole, icariin) extracted from plants known to improve sexual performance. Only 31% of the samples could be considered as true herbal/natural products. A follow-up over time of several DS revealed that manufacturers make changes in the chemical composition of the formulations. Lack of quality or consistent manufacture (contamination possibly due to inadequate cleaning of the manufacturing chain, presence of impurities or degradation products, various compositions of a given DS with the same batch number, inadequate labelling) indicated poor manufacturing practices. In conclusion, this paper demonstrates the power of (1)H NMR spectroscopy as a first-line method for the detection of adulterated herbal/natural DS and the need for more effective quality control of purported herbal DS.


Assuntos
Afrodisíacos/análise , Suplementos Nutricionais/análise , Contaminação de Medicamentos , Espectroscopia de Ressonância Magnética/métodos , Marketing , Preparações de Plantas/análise , Afrodisíacos/economia , Suplementos Nutricionais/economia , Hidrogênio , Marketing/economia , Inibidores da Fosfodiesterase 5/análise , Inibidores da Fosfodiesterase 5/economia , Preparações de Plantas/economia , Comportamento Sexual/efeitos dos fármacos
10.
Anal Chem ; 86(23): 11897-904, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25337675

RESUMO

Nuclear magnetic resonance (NMR) spectroscopy is a unique tool for detection, structural characterization, and quantification of compounds in complex mixtures. However, due to cost constraints, NMR is rarely used in routine quality control (QC) analysis. The recent release of benchtop cryogen-free low-field NMR spectrometers represents a technological break in the NMR field. In this paper, we evaluated the potential of a benchtop cryogen-free 60 MHz spectrometer for uncovering adulteration of "100% natural" sexual enhancement and weight loss dietary supplements. We demonstrated that the adulterant(s) can readily be detected in ≈20 min of recording after a very simple and rapid sample preparation. We also showed that the quantification by the internal standard method can be done on the low-field NMR spectrometer and leads to results similar to those obtained with high-field NMR. Considering the cost and space efficiency of these spectrometers, we anticipate their introduction in QC laboratories as well as in governmental agencies, especially in the field of fraud detection.


Assuntos
Suplementos Nutricionais/análise , Contaminação de Medicamentos , Espectroscopia de Ressonância Magnética/instrumentação , Preparações Farmacêuticas/análise , Redução de Peso , Prótons
11.
J Pharm Biomed Anal ; 98: 446-62, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25038499

RESUMO

The purpose of the study was to investigate the degradation pathway of 5-fluorouracil (FU) in the situation of commercial formulations for clinical use, namely FU dissolved in sodium hydroxide (NaOH) solutions or Tris buffer at pH 8.5-9. Combination of data from (19)F, (1)H and (13)C NMR and in some cases MS led to the identification of 8 and 13 FU degradation products in NaOH and Tris solutions respectively. In FU NaOH solutions, the first stage of FU degradation is a stereoselective hydration of the C5-C6 double bond leading to 5,6-dihydro-5-fluoro-6-hydroxyuracil, the cis stereoisomer being predominant relative to the trans. The second stage involves either a defluorination step with formation of fluoride ion and 5-hydroxyuracil or the cleavage of the N3-C4 bond giving the two diastereoisomeric 2-fluoro-3-hydroxy-3-ureidopropanoic acids. The subsequent N1-C6 bond breakdown of these compounds releases urea and 2-fluoro-3-oxopropanoic acid (FOPA) which in turn losses easily carbon dioxide leading to the formation of fluoroacetaldehyde (Facet). The degradation pathway in FU-Tris solutions is identical, except that Tris reacts with the aldehydes FOPA and Facet to form oxazolidine adducts stable at pH 8.5 but in equilibrium with the aldehyde forms at physiological pH, whereas the high reactivity of free aldehydes leads to numerous unidentified degradation compounds all in very low amounts. The FOPA diastereoisomeric adducts react with Facet to form four diastereoisomeric fused bicyclic five-membered ring compounds. Facet and FOPA are highly cardiotoxic. In Tris formulations, they are trapped as stable oxazolidine adducts which release the free aldehydes at physiological pH thus explaining the higher cardiotoxicity of FU in Tris solutions compared to that of FU in NaOH solutions.


Assuntos
Fluoruracila/química , Soluções/química , Química Farmacêutica/métodos , Concentração de Íons de Hidrogênio , Hidrólise , Espectroscopia de Ressonância Magnética/métodos , Hidróxido de Sódio/química , Uracila/análogos & derivados , Uracila/química
12.
Metabolites ; 4(1): 115-28, 2014 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-24958390

RESUMO

Two publications from the same research group reporting on the detection of new possible biomarkers for the early diagnosis of Alzheimer's disease (AD), based on the analysis of cerebrospinal fluid samples (CSF) with 1H Nuclear Magnetic Resonance (NMR), are at the origin of the present study. The authors observed significant differences in 1H NMR spectra of CSF from AD patients and healthy controls and, thus, proposed some NMR signals (without attribution) as possible biomarkers. However, this work was carried out in non-standardized pH conditions. Our study aims at warning about a possible misinterpretation that can arise from 1H NMR analyses of CSF samples if pH adjustment is not done before NMR analysis. Indeed, CSF pH increases rapidly after removal and is subject to changes over conservation time. We first identify the NMR signals described by the authors as biomarkers. We then focus on the chemical shift variations of their NMR signals as a function of pH in both standard solutions and CSF samples. Finally, a principal component analysis of 1H NMR data demonstrates that the same CSF samples recorded at pH 8.1 and 10.0 are statistically differentiated.

13.
Forensic Sci Int ; 234: 29-38, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24378299

RESUMO

Twenty-four samples of heroin from different illicit drug seizures were analyzed using proton Nuclear Magnetic Resonance ((1)H NMR) and two-dimensional diffusion-ordered spectroscopy (2D DOSY) (1)H NMR. A careful assignment and quantification of (1)H signals enabled a comprehensive characterization of the substances present in the samples investigated: heroin, its main related impurities (6-acetylmorphine, acetylcodeine, morphine, noscapine and papaverine) and cutting agents (caffeine and acetaminophen in nearly all samples as well as lactose, lidocaine, mannitol, piracetam in one sample only), and hence to establish their spectral signatures. The good agreement between the amounts of heroin, noscapine, caffeine and acetaminophen determined by (1)H NMR and gas chromatography, the reference method in forensic laboratories, demonstrates the validity of the (1)H NMR technique. In this paper, 2D DOSY (1)H NMR offers a new approach for a whole characterization of the various components of these complex mixtures.

14.
J Alzheimers Dis ; 39(1): 121-43, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24145382

RESUMO

In the quest for biomarkers of onset and progression of Alzheimer's disease, a 1H NMR-based metabolomic study was performed on the simple single-transgenic Tg2576 mouse model. These mice develop a slow cognitive decline starting by 6 months and express amyloid plaques from 10 months of age. The metabolic profiles of extracts from five brain regions (frontal cortex, rhinal cortex, hippocampus, midbrain, and cerebellum) of Tg2576 male mice were compared to those of controls, at 1, 3, 6 and 11 months of age. The most obvious differences were due to brain regions. Age was also a discriminating parameter. Metabolic perturbations were already detected in the hippocampus and the rhinal cortex of transgenic mice as early as 1 month of age with decreased concentrations of glutamate (Glu) and N-acetylaspartate (NAA) compared to those in wild-type animals. Metabolic changes were more numerous in the hippocampus and the rhinal cortex of 3 month-old transgenic mice and involved Glu, NAA, myo-inositol, creatine, phosphocholine, and γ-aminobutyric acid (only in the hippocampus) whose concentrations decreased. A metabolic disruption characterized by an increase in the hippocampal concentrations of Glu, creatine, and taurine was detected in 6 month-old transgenic mice. At this time point, the chemical profile of the cerebellum was slightly affected. At 11 months, all the brain regions analyzed (except the frontal cortex) were metabolically altered, with mainly a marked increase in the formation of the neuroprotective metabolites creatine and taurine. Our findings demonstrate that metabolic modifications occur long before the onset of behavioral impairment.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Cerebelo/metabolismo , Córtex Cerebral/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Mesencéfalo/metabolismo , Metaboloma/fisiologia , Envelhecimento/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Biomarcadores/metabolismo , Modelos Animais de Doenças , Genótipo , Ácido Glutâmico/metabolismo , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Extratos de Tecidos/metabolismo
15.
J Pharm Biomed Anal ; 63: 135-50, 2012 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-22365331

RESUMO

Nine herbal dietary supplements intended to be beverages for enhancing sexual performance were analyzed before their possible launch on the market. Four of them contained a sildenafil analog reported for the first time as an adulterant. After isolation and characterization using NMR, MS, IR and UV, this analog was named propoxyphenyl-thiohydroxyhomosildenafil as the ethoxy chain on the phenyl ring of the already known analog thiohydroxyhomosildenafil was replaced by a propoxy moiety. One formulation was tainted with thiosildenafil, another unapproved PDE-5 inhibitor. Sildenafil along with the natural alkaloid tetrahydropalmatine that has no documented effect for enhancing erectile dysfunction were identified in two formulations. Another formulation was adulterated with phentolamine, a drug that is not approved for boosting male sexual performance when taken orally. The last formulation containing osthole, a bioactive natural coumarine improving sexual dysfunction, is most probably truly natural.


Assuntos
Afrodisíacos/análise , Alcaloides de Berberina/análise , Suplementos Nutricionais/análise , Contaminação de Medicamentos , Fentolamina/análise , Inibidores da Fosfodiesterase 5/análise , Piperazinas/análise , Preparações de Plantas/análise , Compostos de Sulfidrila/análise , Sulfonas/análise , Afrodisíacos/farmacologia , Alcaloides de Berberina/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Estrutura Molecular , Ereção Peniana/efeitos dos fármacos , Fentolamina/farmacologia , Inibidores da Fosfodiesterase 5/farmacologia , Piperazinas/farmacologia , Preparações de Plantas/farmacologia , Purinas/análise , Purinas/farmacologia , Comportamento Sexual/efeitos dos fármacos , Citrato de Sildenafila , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Sulfidrila/farmacologia , Sulfonas/farmacologia , Espectrometria de Massas em Tandem
16.
J Pharm Biomed Anal ; 59: 58-66, 2012 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-22030075

RESUMO

iErect, a new dietary supplement marketed as "100% natural" and sold over the Internet, was analyzed. It contains thiosildenafil, a sildenafil analogue already reported as an adulterant in herbal formulations, and a new compound whose structure was elucidated after isolation using NMR, MS and IR. It was named depiperazinothiosildenafil as it results from the hydrolytic cleavage of the S-N bond of the sulfonamide group of thiosildenafil. A capsule of iErect contains a very high amount (≈220mg) of thiosildenafil and ≈30mg of depiperazinothiosildenafil, which places consumers at risk for potentially serious side-effects.


Assuntos
Suplementos Nutricionais/análise , Suplementos Nutricionais/normas , Contaminação de Medicamentos , Piperazinas/isolamento & purificação , Preparações de Plantas/análise , Preparações de Plantas/normas , Pirimidinas/isolamento & purificação , Sulfonas/isolamento & purificação , Tionas/isolamento & purificação , Cápsulas , Cromatografia Líquida de Alta Pressão , Contaminação de Medicamentos/legislação & jurisprudência , Espectroscopia de Ressonância Magnética , Piperazinas/química , Purinas/química , Purinas/isolamento & purificação , Pirimidinas/química , Citrato de Sildenafila , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfonas/química , Espectrometria de Massas em Tandem , Tionas/química
17.
Bioorg Med Chem ; 18(24): 8537-48, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21067931

RESUMO

A convenient route for the synthesis of some acyloxymethyl esters and carboxamides of levofloxacin (LV) with modulated lipophilicity is described. The synthesized compounds were evaluated in vitro for their growth inhibitory effect in five human cancer cell lines. The most efficient LV derivatives (ester 2e and amide 4d) displayed IC(50) values in the 0.2-2.2 µM range, while IC(50) values for parent LV ranged between 70 and 622 µM depending on the cell line. The esters displayed no in vivo toxicity up to 80 mg/kg when administered intraperitoneally. This study thus shows that LV analogs displayed antitumor efficacy, at least in vitro, a feature that appeared to be independent from the lipophilicity of the grafted substituent.


Assuntos
Antineoplásicos/síntese química , Derivados de Benzeno/síntese química , Ácidos Carboxílicos/síntese química , Amidas , Antineoplásicos/farmacologia , Derivados de Benzeno/farmacologia , Ácidos Carboxílicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ésteres , Humanos , Interações Hidrofóbicas e Hidrofílicas , Concentração Inibidora 50 , Levofloxacino , Ofloxacino
18.
Magn Reson Chem ; 47 Suppl 1: S163-73, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19655367

RESUMO

Two-dimensional diffusion ordered spectroscopy (DOSY) (1)H NMR is proposed to analyze drugs that are complex mixtures in order to discriminate genuine from fake formulations. The method was applied to the analysis of 17 formulations of sildenafil, one being genuine Viagra and the others illegally manufactured formulations of this drug coming from India, Syria and China. It enabled (i) distinguishing imitations or counterfeit from the authentic formulation, (ii) detecting the presence of sildenafil or adulterants, (iii) gaining information on the formulation process by detection of various excipients, thus giving a precise and global 'signature' of the manufacturer. Even though some samples are slightly overdosed, the quality of products manufactured in India and Syria was better than that of Chinese formulations which were adulterated with vardenafil and homosildenafil. This study also presents a three-dimensional DOSY-COSY (1)H NMR experiment that provides both virtual separation and structural information.


Assuntos
Contaminação de Medicamentos , Espectroscopia de Ressonância Magnética/métodos , Piperazinas/química , Sulfonas/química , China , Cromatografia Líquida de Alta Pressão , Misturas Complexas/análise , Índia , Estrutura Molecular , Purinas/química , Citrato de Sildenafila , Síria
19.
Bioorg Med Chem ; 17(15): 5396-407, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19595598

RESUMO

Ciprofloxacin (CP), an antibiotic has been shown to have antiproliferative and apoptotic activities in several cancer cell lines. Moreover, several reports have highlighted the interest of increasing the lipophilicity to improve the antitumor efficacy. These studies have led us to synthesize new CP derivatives of various lipophilicities and to evaluate their activity in five human cancer cell lines. With an easy and cost-efficient procedure, 31 7-((4-substituted)piperazin-1-yl) derivatives of CP were prepared that displayed IC(50) values ranging from microM to mM concentrations and are non-toxic in vivo in healthy mice as shown by their maximal tolerated dose (MTD) indices >80 mg/kg. Several derivatives displayed higher in vitro antitumor activity than parent CP however this was not dependent on the lipophilicity of the substituent. Among all synthesized derivatives, the most potent were 2 and 6h whose IC(50) values were 10 microM in three (derivative 2) or four (derivative 6h) cancer cell lines.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Ciprofloxacina/análogos & derivados , Ciprofloxacina/farmacologia , Piperazinas/química , Piperazinas/farmacologia , Animais , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciprofloxacina/síntese química , Ciprofloxacina/toxicidade , Humanos , Dose Máxima Tolerável , Camundongos , Neoplasias/tratamento farmacológico , Piperazina , Piperazinas/síntese química , Piperazinas/toxicidade
20.
Anal Chem ; 81(12): 4803-12, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19453162

RESUMO

During the past decade, there has been a marked increase in the number of reported cases involving counterfeit medicines in developing and developed countries. Particularly, artesunate-based antimalarial drugs have been targeted, because of their high demand and cost. Counterfeit antimalarials can cause death and can contribute to the growing problem of drug resistance, particularly in southeast Asia. In this study, the complementarity of two-dimensional diffusion-ordered (1)H nuclear magnetic resonance spectroscopy (2D DOSY (1)H NMR) with direct analysis in real-time mass spectrometry (DART MS) and desorption electrospray ionization mass spectrometry (DESI MS) was assessed for pharmaceutical forensic purposes. Fourteen different artesunate tablets, representative of what can be purchased from informal sources in southeast Asia, were investigated with these techniques. The expected active pharmaceutical ingredient was detected in only five formulations via both nuclear magnetic resonance (NMR) and mass spectrometry (MS) methods. Common organic excipients such as sucrose, lactose, stearate, dextrin, and starch were also detected. The graphical representation of DOSY (1)H NMR results proved very useful for establishing similarities among groups of samples, enabling counterfeit drug "chemotyping". In addition to bulk- and surface-average analyses, spatially resolved information on the surface composition of counterfeit and genuine antimalarial formulations was obtained using DESI MS that was performed in the imaging mode, which enabled one to visualize the homogeneity of both genuine and counterfeit drug samples. Overall, this study suggests that 2D DOSY (1)H NMR, combined with ambient MS, comprises a powerful suite of instrumental analysis methodologies for the integral characterization of counterfeit antimalarials.


Assuntos
Antimaláricos/análise , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Composição de Medicamentos , Espectroscopia de Ressonância Magnética/instrumentação , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Comprimidos/química
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