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1.
Ann Ist Super Sanita ; 58(4): 254-263, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36511196

RESUMEN

INTRODUCTION: A case study is reported on anti-motion sickness transdermal patches sold in the Internet, claiming to contain only natural ingredients but, actually, containing undeclared medicinal active substances. The visual inspection of the samples evidenced many inconsistencies in secondary and primary packaging, missing of various legal information and a non-compliant "CE" mark. METHODS: The qualitative analysis was performed by liquid chromatography - high resolution mass spectrometry and the quantitative by liquid chromatography with diode array detector. RESULTS: The analyses evidenced the presence of the antihistaminic drug Diphenhydramine and of other active substances (Capsaicin, a transdermal absorption enhancer, and Diclofenac in traces, probably a contaminant from other productions of the same plant). Moreover, the presence of several trace elements, including those potentially toxic to humans, was assessed by ICP-MS analysis. CONCLUSIONS: The case discussed is a new case of "medicines in disguise" never reported in literature, and shows the presence of tangible risks for public health.


Asunto(s)
Preparaciones Farmacéuticas , Humanos
2.
Water Res ; 197: 117092, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33831774

RESUMEN

The oil-water interface formed during an oil spill represents a challenging environment for pelagic communities living in aquatic ecosystems. At this anoxic barrier, we report the formation of a microbial hydrocarbonoclastic biofilm capable of electron transfer along the water column. This biofilm generated a membrane of surface-active compounds that allowed the spontaneous separation of electrical charges, causing the establishment of an anodic and a cathodic region and, as a result, the spontaneous creation of a liquid microbial fuel cell. Such floating biofilm was connected to the water column underneath by floating filaments that could contribute to oxygen reduction at distance. The filaments revealed an unusual lipid content induced by anoxic conditions, with prominent ultrastructural features similar to myelin found in oligodendrocytes of the vertebrate nervous system. Furthermore, these filaments showed an interesting cross-reactivity towards different epitopes of the myelin basic protein (MBP) and Claudin 11 (O4) of human oligodendrocytes. The presence of a network of filaments similar to myelin suggests the probable existence of evolutionary connections between very distant organisms. Collectively these results suggest a possible mechanism for how lake microbial communities can adapt to oil spills while offering an interesting starting point for technological developments of liquid microbial fuel cells related to the study of hydrocarbon-water interfaces. The data that support the findings of this study are openly available in figshare at https://figshare.com/s/72bc73ae14011dc7920d.


Asunto(s)
Contaminación por Petróleo , Biopelículas , Ecosistema , Humanos , Hidrocarburos , Contaminación por Petróleo/análisis , Agua
3.
Talanta ; 198: 337-343, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-30876570

RESUMEN

This paper describes a case of medicine in disguise: seized tattoo inks containing lidocaine and tetracaine at high concentration. Identification of anaesthetics was performed by LC MS Q-TOF with ESI+ source, by accurate mass measurement and by comparing the fragmentation patterns of molecular ions, at 30 V and 10 V of collision-offset voltage, with reference standards. Quantification was also performed by LC MS Q-TOF on the chromatographic peaks in the extracted ion chromatograms, by calibration curves obtained at different standard concentrations and by standard additions approach. The measurement uncertainty was estimated from validation data. The paper gives also chromatographic parameters, MS and MS/MS data and a quantitation method, with a full validation, of other six "caines". Thus the paper intends to provide a tool for identification and quantitation of the most common local anaesthetics that could be fraudulently added to tattoo inks. The results here reported show that the seized samples of inks represent a serious health risk owing to the high anaesthetic content - therapeutic-like dosage - found.


Asunto(s)
Anestésicos/análisis , Tinta , Lidocaína/análisis , Tatuaje , Tetracaína/análisis , Cromatografía Liquida , Humanos , Espectrometría de Masas
4.
J Pharm Biomed Anal ; 162: 158-163, 2019 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-30243055

RESUMEN

Adverse reactions have been reported for antibiotics produced via fermentation with fish peptone due to Histamine contamination. Just few micrograms of Histamine can result in adverse reactions when administered intravenously. Thus in this paper a new method for identification and quantitation of Histamine at ppm levels in the antibiotic Gentamicin is described. The method is based on separation of Histamine from Gentamicin and other excipients present in the drug matrix, by hydrophilic interaction liquid chromatography (HILIC) coupled to a Q-TOF/MS detector; quantitation is based on the standard addition approach. The method was validated for repeatability, inter-day precision, specificity, accuracy (relative and absolute bias) linearity, limit of detection and quantitation. Uncertainty was estimated and evaluated by comparison with values expected according to the Horwitz theory. The method showed satisfactory performances and good sensitivity, reaching a limit of quantitation of approximately 1 ppm. The method proposed can be a starting point for the development of Histamine quantitation methods in other antibiotics or even in other medicinal products which active ingredient is produced via fermentation in presence of fish peptone.


Asunto(s)
Antibacterianos/análisis , Cromatografía Liquida , Contaminación de Medicamentos , Gentamicinas/análisis , Histamina/análisis , Espectrometría de Masas en Tándem , Calibración , Cromatografía Liquida/normas , Histamina/efectos adversos , Estándares de Referencia , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/normas , Incertidumbre
5.
Ann Ist Super Sanita ; 52(1): 128-32, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27033629

RESUMEN

OBJECTIVES: The increasing illegal and on-line market of medicines and food supplements is helping the widespread diffusion of harmful counterfeit and forbidden products among consumers of developed countries. The objectives of this survey were the description of the main frauds recognized by public officers and the detection of illegal or counterfeit drugs and food supplements. METHODS: Medicines and food supplements found by Police forces on the illegal market or resulting from seizures made by Italian Customs authorities were visually inspected and analysed to evaluate their quality and the presence of other undeclared substances. RESULTS: The visual inspection and the chemical analysis revealed unsuitable packaging (mostly lacking of adequate information for consumers), absence of the declared active substances and presence of undeclared active substances. Products containing doping agents, illegal substances and active ingredients requiring medical supervision were found. CONCLUSION: The present work confirmed the health risk associated with assumption of medicines purchased on the Internet and from the illegal supply chain and evidenced a new threat to consumer safety related to the presence of pharmaceutical active ingredients in food supplements claiming to contain only "natural ingredients".


Asunto(s)
Medicamentos Falsificados , Suplementos Dietéticos , Tráfico de Drogas , Drogas Ilícitas/efectos adversos , Internet , Seguridad de Productos para el Consumidor , Etiquetado de Medicamentos , Humanos , Italia , Preparaciones Farmacéuticas/análisis , Medición de Riesgo , Encuestas y Cuestionarios
6.
J Pharm Biomed Anal ; 96: 170-86, 2014 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-24747148

RESUMEN

Novel synthetic analogs of Sildenafil are constantly detected as adulterants in counterfeit drugs and dietary supplements. Their intake constitutes a serious health hazard as side effects are unknown. In this paper an investigation is carried out on NMR and MS/MS spectra of Sildenafil, Thiosildenafil, Acetildenafil and thirteen of their analogs: a list of key signals is reported and discussed with the intent to provide a tool that can help in detecting adulteration and in elucidating the structure of novel analogs. In this view extensive spectral data were reported, discussed and summarized in tables. A discussion on mass fragmentation and NMR chemical shifts is also provided to rationalize assignation. Moreover, a comprehensive information on the route of synthesis is provided for the benefit of those medicines control laboratories that need to synthesize analogs reference standards in-house.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Piperazinas/análisis , Pirimidinas/análisis , Sulfonas/análisis , Espectrometría de Masas en Tándem/métodos , Medicamentos Falsificados/análisis , Suplementos Dietéticos/análisis , Contaminación de Medicamentos , Inhibidores de Fosfodiesterasa 5/análisis , Inhibidores de Fosfodiesterasa 5/química , Piperazinas/química , Purinas/análisis , Purinas/química , Pirimidinas/química , Citrato de Sildenafil , Sulfonas/química
7.
J Sex Med ; 9(8): 2130-7, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22612848

RESUMEN

INTRODUCTION: In developed countries the phenomenon of pharmaceutical counterfeiting is steadily increasing through the illegal and the Internet market. Medicines for the treatment of erectile dysfunctions containing phosphodiesterase type 5 inhibitors (PDE5) are especially prone to falsification. AIMS: To obtain evidence of the health risks for patients taking these products and to provide useful information to general practitioners and specialists in sexual medicine. METHODS: First the samples were visually inspected and then analyzed to get information about their identity and quality. MAIN OUTCOME MEASURES: A survey on the PDE5 medicines analyzed by the Italian official medicines control laboratory between 2005 and 2011 was performed. All the analyzed medicines were gathered from the Italian illegal market (seizures by police forces) or were bought from illegal online pharmacies. Results. The study revealed that 24% of the analyzed samples were counterfeit and 54% were illegal medicines. In 12% of the cases an intermediate classification (illegal/counterfeit) was assigned. Only 7% of the samples were original. Moreover, the examination of the packaging evidenced potential risks: outer and immediate packaging missing; inconsistency between the carton box and the blister as regards the expiry date and/or the batch number; expiry date or manufacturer's name or country missing. CONCLUSIONS: In 19% of the samples a potential health risk for patients was identified due to either the presence in the sample of more than one undeclared PDE5(s) or an amount of the active ingredient higher than that declared (up to 190% of the maximum dose) or to the presence of potentially dangerous excipients of non-pharmaceutical origin or quality (e.g., gypsum or non-purified talc).


Asunto(s)
Medicamentos Falsificados/administración & dosificación , Medicamentos Falsificados/efectos adversos , Disfunción Eréctil/tratamiento farmacológico , Fraude , Humanos , Internet , Italia , Masculino , Persona de Mediana Edad , Inhibidores de Fosfodiesterasa 5
8.
NMR Biomed ; 25(4): 632-42, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22020805

RESUMEN

Magnetic resonance imaging (MRI) and spectroscopy (MRS) offer powerful approaches for detecting physiological and metabolic alterations in malignancies and help investigate underlying molecular mechanisms. Research on epithelial ovarian carcinoma (EOC), the gynaecological malignancy with the highest death rate characterised by frequent relapse and onset of drug resistance, could benefit from application of these molecular imaging approaches. In this study, MRI/MRS were used to characterise solid tumour models obtained by subcutaneous (s.c.) or intraperitoneal (i.p.) implantation of human SKOV3.ip cells in severe combined immunodeficiency (SCID) mice. In vivo MRI/MRS, ex vivo magic-angle-spinning (MAS), and in vitro (1)H-NMR measurements were carried out at 4.7 T, 9.4 T, and 9.4/16.5 T, respectively. MRI evaluation was performed by T1-, T2-, and diffusion-weighted (DW) multislice spin-echo imaging. The in vivo (1)H spectra of all tumour models showed a prominent resonance of total choline-containing metabolites (tCho). Quantitative in vivo MRS of both i.p. and s.c. SKOV3.ip xenografts showed that the mean tCho content was in the 2.9-4.5 mM range, with a mean PCho/tCho ratio of 0.99 ± 0.01 [23 examinations, 14-34 days post injection (dpi)], in good agreement with ex vivo and in vitro analyses. Myo-inositol ranged between 11.7 and 17.0 mM, with a trend towards higher values in i.p. xenografts at 14-16 dpi. The average apparent diffusion coefficient (ADC) values of SKOV3.ip xenografts [1.64 ± 0.11 (n = 9, i.p.) and 1.58 ± 0.03 x10(-3) mm(2)/s (n = 7, s.c.)] were in agreement with values reported for tumours from patients with EOC, while the mean vascular signal fraction (VSF) was lower (≤ 4%), probably due to the more rapid growth of preclinical models. Both s.c. and i.p. xenografts are valuable preclinical models for monitoring biochemical and physiopathological changes associated with in vivo EOC tumour growth and response to therapy, which may serve as the basis for further clinical development of noninvasive MR approaches.


Asunto(s)
Biomarcadores de Tumor/análisis , Diagnóstico por Computador/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética/métodos , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/metabolismo , Animales , Línea Celular Tumoral , Femenino , Humanos , Ratones , Ratones Desnudos , Protones , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
J Pharm Biomed Anal ; 53(2): 215-20, 2010 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-20547026

RESUMEN

The growth of pharmaceutical counterfeiting is a major public health problem. This growth is resulting in a proportional increase in the number of samples that medicines control laboratories have to test. Thus the need for simple and affordable preliminary screening methods to be used by inspectors to decide in the field whether to collect a sample for further laboratory analysis or not. This paper intends to evaluate the possibility to employ for preliminary examinations of suspicious samples an optical spectrophotometer (colorimeter) used in the graphic industry, capable of measuring the reflectance visible spectrum of solid materials. The colorimeter was tested on original and counterfeited Viagra, Cialis and Levitra by measuring the colour of tablets' surface and of a specific spot of the packages. Various batches of the original drugs were employed both to investigate precision and robustness of the technique and to build spectral libraries. These libraries were used to compare suspicious samples to the corresponding original by means of a wavelength distance pattern recognition method. The method was eventually tested on suspicious samples sized by police authorities in order to evaluate its effectiveness. The device resulted precise and robust toward ambient conditions changes, although some limits emerged: the libraries of original samples need a frequent update and a lower precision is to be expected for tablets which surface is extremely convex.


Asunto(s)
Colorimetría/instrumentación , Fraude/prevención & control , Reconocimiento de Normas Patrones Automatizadas/métodos , Comprimidos/análisis , Colorimetría/métodos , Embalaje de Medicamentos , Propiedades de Superficie
10.
J Pharm Biomed Anal ; 48(2): 477-81, 2008 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-18599248

RESUMEN

Diclofenac sodium is a nonsteroidal anti-inflammatory drug widely used in painful and inflammatory diseases. It can exist in different hydrate phases. Recently the physico-chemical and pharmaceutical properties of a trihydrate form, named DSH3 were reported by the same authors. This short communication discusses how samples of a same polymorphic form can display dissimilar analytical signatures when obtained by different routes. Data from hot-stage microscopy, FT-IR spectroscopy, X-ray powder diffraction (XRDP) and thermal analysis were used to characterise the DSH3 samples prepared by different methods. Through the case study of diclofenac sodium, this work highlights how the method used to prepare a specific crystal modification can generate samples with different morphologies and therefore different properties and physical stability.


Asunto(s)
Diclofenaco/química , Cristalización , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
11.
J Med Chem ; 51(4): 1058-62, 2008 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-18232652

RESUMEN

Some synthesized 1,2-dihydrospiro[isoquinoline-4(3 H),4'-piperidin]-3-ones were evaluated as ligands for nociceptin receptor (NOP receptor). Their affinity was established by binding studies, and efficacy was investigated by GTP binding experiments. Selectivity toward DOP, KOP, and MOP receptors was assessed, and structural requirements affecting affinity and selectivity were remarked. Most notably, compound 6d displayed nanomolar NOP receptor affinity and showed more than 800-fold selectivity. The new structures exerted full or partial agonistic activity.


Asunto(s)
Ciclohexanos/síntesis química , Isoquinolinas/síntesis química , Piperidinas/síntesis química , Receptores Opioides/agonistas , Compuestos de Espiro/síntesis química , Línea Celular , Ciclohexanos/química , Ciclohexanos/farmacología , Humanos , Isoquinolinas/química , Isoquinolinas/farmacología , Modelos Moleculares , Piperidinas/química , Piperidinas/farmacología , Ensayo de Unión Radioligante , Compuestos de Espiro/química , Compuestos de Espiro/farmacología , Relación Estructura-Actividad , Receptor de Nociceptina
12.
Environ Mol Mutagen ; 48(9): 754-71, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18008355

RESUMEN

Because of its environmental and industrial importance, the aromatic amines are the single chemical class most studied for its ability to induce mutations and cancer. The large database of mutagenicity and carcinogenicity results has been studied with Quantitative Structure-Activity Relationship (QSAR) approaches by several authors, leading to models for the following: (a) the mutagenic potency in Salmonella thyphimurium; (b) the carcinogenic potency in rodents; and (c) the discrimination between rodent carcinogens and noncarcinogens. However, satisfactory models for the discrimination between mutagens and nonmutagens are lacking. The present work provides new QSARs for mutagenic/nonmutagenic homocyclic aromatic amines in S. typhimurium strains TA98 and TA100. The two new models are validated by checking their ability to predict the mutagenicity of further aromatic amines not included in the training set, and not used to generate the QSAR models. In addition, we also validated previous QSAR models for the carcinogenicity/noncarcinogenicity of the aromatic amines with external data. The mechanistic implications of the models are discussed in light of the other QSARs for the aromatic amines. The results of the analysis point to two QSAR models (one for mutagenicity and one for rodent carcinogenicity) as reliable tools for the in silico characterization of the risk posed by the aromatic amines.


Asunto(s)
Aminas/toxicidad , Carcinógenos/toxicidad , Mutágenos/toxicidad , Modelos Químicos , Relación Estructura-Actividad Cuantitativa , Salmonella typhimurium/genética
13.
J Pharm Biomed Anal ; 45(3): 443-9, 2007 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-17709225

RESUMEN

Diclofenac sodium is a non-steroidal anti-inflammatory drug widely used in painful and inflammatory diseases. It can exist in different hydrate phases. By exposure to different conditions of temperature and relative humidity can be isolated a trihydrate form never described in literature. The methods of preparation of the trihydrate form (named DSH3) were described and its physico-chemical properties were investigated. Data from FTIR spectroscopy, X-ray powder diffraction and thermal analysis were used for identification and characterisation of DSH3 in comparison with the anhydrous form (DS, the commercial form) and the hydrate form DSH (obtained by exposure of DS to relative humidity even below 60% and already described and characterised in a previous article of the same authors). Intrinsic dissolution studies were performed to compare the pharmaceutical properties of DS and DSH with DSH3, since this form was accidentally found on the Italian market as active pharmaceutical ingredient (API). This work stresses the importance of assessing the correct crystalline form also in API of well-established use to guarantee quality, safety and efficacy of the final dosage form. Furthermore, this study suggests that isomorphic hydrate forms with a different dislocation of water within the crystal structures can exist.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Diclofenaco/química , Rastreo Diferencial de Calorimetría , Cristalización , Estabilidad de Medicamentos , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Agua/química , Difracción de Rayos X
14.
Anal Biochem ; 367(1): 111-21, 2007 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-17512489

RESUMEN

Proton nuclear magnetic resonance (NMR) spectroscopy was used to identify and quantify the metabolites present in cultured mouse fibroblast cells 3T6 in their native state and after treatment with PD166866, an inhibitor of the fibroblast growth factor receptor. Cell extracts were prepared according to the Bligh-Dyer protocol which prevents artifacts deriving from the chemical demolition of macromolecules. Also the growth medium was subjected to the same extraction procedure. The NMR approach made possible the identification and quantification of about 40 different metabolites at nanomoles/mg of protein level: the biological relevance of the variation of some metabolite levels is discussed. Our experimental procedure offers a prospective method for the evaluation of variations of the metabolic profile deriving from different biochemical treatments of these cells.


Asunto(s)
Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/antagonistas & inhibidores , Aminoácidos/metabolismo , Animales , Línea Celular , Dimetilsulfóxido , Inhibidores Enzimáticos/farmacología , Ratones , Resonancia Magnética Nuclear Biomolecular/métodos , Nucleótidos/metabolismo , Pirimidinas/farmacología , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Urea/análogos & derivados , Urea/farmacología
15.
Bioorg Chem ; 35(3): 243-57, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17303215

RESUMEN

Two acetylcholinesterase (AChE) inhibitors structurally related to Tacrine, 6-methoxytacrine (1a) and 9-heptylamino-6-methoxytacrine (1b), and their interaction with Electrophorus Electricus AChE were investigated. The complete assignment of the 1H and 13C NMR spectra of 1a and 1b was performed by mono-dimensional and homo- and hetero-correlated two-dimensional NMR experiments. This study was undertaken to elucidate the interaction modes between AChE and 1a and 1b in solution, using NMR. The interaction between the two inhibitors and AChE was studied by the analysis of the motional parameters non-selective and selective spin-lattice relaxation times, thereby allowing the motional state of 1a and 1b, both free and bound with AChE, to be defined. The relaxation data pointed out the ligands molecular moiety most involved in the binding with AChE. The relevant ligand/enzyme interaction constants were also evaluated for both compounds and resulted to be 859 and 5412M(-1) for 1a and1b, respectively.


Asunto(s)
Acetilcolinesterasa/química , Espectroscopía de Resonancia Magnética/métodos , Tacrina/análogos & derivados , Tacrina/química , Acetilcolinesterasa/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Ligandos , Espectroscopía de Resonancia Magnética/normas , Estructura Molecular , Protones , Estándares de Referencia , Sensibilidad y Especificidad , Relación Estructura-Actividad , Tacrina/farmacología
16.
J Pharm Biomed Anal ; 42(1): 56-63, 2006 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-16870384

RESUMEN

A measurement result cannot be properly interpreted if not accompanied by its uncertainty. Several methods to estimate uncertainty have been developed. From those methods three in particular were chosen in this work to estimate the uncertainty of the Eu. Ph. chloroquine phosphate assay, a potentiometric titration commonly used in medicinal control laboratories. The famous error-budget approach (also called bottom-up or step-by-step) described by the ISO Guide to the expression of Uncertainty in Measurement (GUM) was the first method chosen. It is based on the combination of uncertainty contributions that have to be directly derived from the measurement process. The second method employed was the Analytical Method Committee top-down which estimates uncertainty through reproducibility obtained during inter-laboratory studies. Data for its application were collected in a proficiency testing study carried out by over 50 laboratories throughout Europe. The last method chosen was the one proposed by Barwick and Ellison. It uses a combination of precision, trueness and ruggedness data to estimate uncertainty. These data were collected from a validation process specifically designed for uncertainty estimation. All the three approaches presented a distinctive set of advantages and drawbacks in their implementation. An expanded uncertainty of about 1% was assessed for the assay investigated.


Asunto(s)
Cloroquina/análogos & derivados , Cloroquina/análisis , Potenciometría , Incertidumbre
18.
J Pharm Biomed Anal ; 40(5): 1105-13, 2006 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-16256287

RESUMEN

Diclofenac sodium is a non-steroidal anti-inflammatory drug widely used in painful and inflammatory diseases. In standard conditions, by exposure to relative humidity even below 60% at 25 degrees C, the anhydrous form DS gives rise to a hydrate species DSH, a tetrahydrate form different from that obtained by crystallisation from water and previously described. The method of preparation and the physico-chemical properties of the hydrate form were investigated. Data from FTIR spectroscopy, X-ray powder diffraction and thermal analysis were used for the identification and the characterisation of DSH. DS and DSH were easily differentiated by their IR spectra, X-ray patterns and thermal behaviour. DSH stability was followed at room temperature over a period of 1 year and under different conditions of temperature to verify the tendency to solid-solid transition and to study its existence range. Solubility and intrinsic dissolution studies were performed to compare the physico-chemical properties of DS and DSH. Differences in solubility and intrinsic dissolution rates were pointed out: these studies showed that DS dissolved faster than DSH. Storage under uncontrolled environmental conditions or contact with water vapour during manufacturing process could thus influence the performance of the final dosage form.


Asunto(s)
Diclofenaco/química , Calibración , Fenómenos Químicos , Química Física , Humedad , Indicadores y Reactivos , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Agua , Difracción de Rayos X
19.
Environ Mol Mutagen ; 46(4): 268-80, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15991240

RESUMEN

Aldehydes are widespread environmental and industrial compounds, able to stimulate a range of adverse health effects (e.g., general toxicity, allergenic reactions, mutagenicity, and carcinogenicity). We have previously presented quantitative structure-activity relationships (QSARs) for the genotoxicity of simple and alpha,beta-unsaturated aliphatic aldehydes. In this study, we show that the QSAR models are able to correctly predict--based only on the knowledge of the chemical structure--the genotoxicity of other aldehydes, not considered in the development phase of the models. This adds confidence to the reliability of our QSAR models as tools for the theoretical assessment of the genotoxic hazard posed by aldehydes. The analysis of SOS Chromotest induction ability and the ease of formation of DNA adducts by the aldehydes provided further mechanistic insights.


Asunto(s)
Aldehídos/química , Aldehídos/toxicidad , Aductos de ADN/efectos de los fármacos , Mutágenos/química , Mutágenos/toxicidad , Relación Estructura-Actividad Cuantitativa , Simulación por Computador , Estructura Molecular , Pruebas de Mutagenicidad , Salmonella/efectos de los fármacos
20.
Eur J Med Chem ; 39(12): 1047-57, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15571866

RESUMEN

A series of 4-amino-2-methylquinoline and 4-aminoquinazoline derivatives, including the reference NOP antagonist JTC-801, were synthesized by an alternative pathway and their in vitro pharmacological properties were investigated. 3-Substitution of the quinoline ring resulted very critical for affinity. So 3-methyl derivative 4j showed a similar potency compared with the reference 4h while bulky lipophilic or electron withdrawing groups in the same position strongly decreased affinity. Structural and conformational requirements for affinity were outlined by NOE NMR and computational methods and suggestions for a pharmacophore model design were provided.


Asunto(s)
Aminoquinolinas/síntesis química , Benzamidas/síntesis química , Antagonistas de Narcóticos , Aminoquinolinas/química , Aminoquinolinas/metabolismo , Aminoquinolinas/farmacología , Benzamidas/química , Benzamidas/metabolismo , Benzamidas/farmacología , Unión Competitiva , Calorimetría , Relación Dosis-Respuesta a Droga , Proteínas de Unión al GTP/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Humanos , Técnicas In Vitro , Modelos Logísticos , Conformación Molecular , Estructura Molecular , Péptidos Opioides/metabolismo , Unión Proteica , Receptores Opioides/metabolismo , Relación Estructura-Actividad , Receptor de Nociceptina , Nociceptina
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