RESUMEN
Tioconazole is an effective antifungal agent with very low solubility in aqueous media, which limits its bioavailability and efficacy. Aiming to overcome the drug limitations by improving the solubility of this active pharmaceutical ingredient, solution precipitation techniques were employed to prepare four new crystalline salts, namely the mesylate, tosylate, maleate (1:1), and fumarate (1:1) hemihydrate. The thermal stabilities, dissolution properties, and structural characteristics of the solids were determined, and the study was extended to compare their properties with the already-known oxalate salt. The structural characterization of the new phases was carried out using a multi-method approach, which included thermal (differential scanning calorimetry and thermogravimetry), diffractometric (powder X-ray diffraction), and spectroscopic (near-infrared and mid-infrared) methodologies. The determination of the melting point of the salts confirmed the findings made by thermal methods. Functional characteristics of the salts, involving their intrinsic dissolution rates were also determined. It was found that the salts exhibited improved thermal stability and that the nature of the counterion modulated their dissolution characteristics. The salts displayed better intrinsic dissolution rates than the free base, to the point of being "highly soluble" according to the Biopharmaceutical Classification System. At pH 4.3, the sulfonic acid derivatives exhibited better dissolution rates than their carboxylic acid-derived counterparts, greatly improved regarding bare tioconazole. The results suggest that the salts have great potential to be used as replacements for the free base; in principle, careful salt selection may help to fulfill each solubility need for the different scenarios where the drug may be used.
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Imidazoles , Sales (Química) , Sales (Química)/química , Difracción de Rayos X , Oxalatos , Solubilidad , Rastreo Diferencial de CalorimetríaRESUMEN
Two novel Cu(I) tetradentate heteroleptic complexes, including nitrile-substituted bipyridines that can be anchored to semiconductor surfaces to be assembled in DSSCs, were synthesized and characterized by spectroscopic and electrochemical techniques. The crystal structures of both species were determined by X-ray diffraction. Results from DFT and TD-DFT calculations were found to be consistent with the experimental data. Emission at room temperature was observed for both complexes in the solid state, making them promising alternatives for the development of light-emitting diodes. We report for the first time the experimental evidence of photovoltaic conversion devices formed by Cu(I) complexes anchored to a TiO2 surface by means of nitrile groups present in substituted bipyridines, and subsequently tested as sensitizers for DSSCs, obtaining efficiency values for light to electrical energy conversion similar to those previously reported for analogous complexes with anchoring carboxylic groups.
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Dilocarcinus pagei is a South American crab commonly found in fishponds. As crabs are a source of astaxanthin (AST) and food inputs, this preliminary research aimed at studying the composition of females and males of this species to assess its potential for commercial applications, and at optimising the extraction of AST with edible oils to promote its use as an ingredient for the nutraceutical, pharmaceutical and feed industries. The chemical composition differed between males and females only in moisture, and the values obtained were: 65.4 ± 1.0% and 72.5 ± 3.1% moisture, 45.7-40.3% d.m. minerals, 22.0-24.1% d.m. fibres, 18.2-17.4% d.m. proteins, and 10.4-11.1% d.m. lipids. The Box-Behnken design was applied and validated for extraction with soya bean and sunflower oils, adjusting the oil:crab ratio, temperature, and extraction time. The optimal conditions found consisted of 140 mL/g, 90 °C and 170 min for soya bean oil, reaching an accumulation of AST of 50 ± 5 µg/g crab d.m. For sunflower oil, the conditions were 60 mL/g, 90 °C and 161 min, reaching 31 ± 3 µg/g crab d.m. Finally, the amounts of AST obtained using soya bean oil were higher than those obtained using sunflower oil; thus, soya bean oil would be recommended as a solvent to extract the pigment.
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Oral candidiasis is an opportunistic infection that affects mainly individuals with weakened immune system. Devices used in the oral area to treat this condition include buccal films, which present advantages over both oral tablets and gels. Since candidiasis causes pain, burning, and itching, the purpose of this work was to develop buccal films loaded with both lidocaine (anesthetic) and miconazole nitrate (MN, antifungal) to treat this pathology topically. MN was loaded in microparticles based on different natural polymers, and then, these microparticles were loaded in hydroxypropyl methylcellulose-gelatin-based films containing lidocaine. All developed films showed adequate adhesiveness and thickness. DSC and XRD tests suggested that the drugs were in an amorphous state in the therapeutic systems. Microparticles based on chitosan-alginate showed the highest MN encapsulation. Among the films, those containing the mentioned microparticles presented the highest tensile strength and the lowest elongation at break, possibly due to the strong interactions between both polymers. These films allowed a fast release of lidocaine and a controlled release of MN. Due to the latter, these systems showed antifungal activity for 24 h. Therefore, the treatment of oropharyngeal candidiasis with these films could reduce the number of daily applications with respect to conventional treatments.
RESUMEN
Tioconazole is an effective antifungal agent, which has a very low solubility in aqueous media, that limits its bioavailability and efficacy. In an effort to overcome the drug limitations by improving its solubility, the hydrochloride salt was prepared in methanolic 1 M HCl and obtained as the hemihydrate, as demonstrated by elemental analysis. Single crystals were grown by slow evaporation from an aqueous 1 M HCl solution and their structure was determined using single-crystal X-ray diffraction at 302 K. The structures resulting from dehydration and further rehydration were also assessed, at 333 and 283 K, respectively. The morphology of the crystal, which exhibited birefringence under polarized light, was verified by hot stage microscopy. The solid was characterized by additional means, including thermal analysis (melting point, differential scanning calorimetry and thermogravimetry), spectroscopic methods (mid infrared, near infrared, 1H, 13C and 15N nuclear magnetic resonance in solution, as well as 13C and 15N solid state with spinning at the magic angle) and X-ray diffraction techniques. Functional evaluation tests, including the intrinsic dissolution rate and the dissolution of powders were also performed. In the intrinsic dissolution rate test, the salt proved to dissolve over 2000 times faster than tioconazole. The results suggest that the new salt has physicochemical and performance properties which may support its use as a replacement of the free base in certain applications, especially where improved dissolution rate, solubility or bioavailability of the drug would be desired.
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Antifúngicos , Cloruro de Sodio , Difracción de Rayos X , Cristalografía por Rayos X , Espectroscopía de Resonancia Magnética , Rastreo Diferencial de Calorimetría , Agua/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier/métodosRESUMEN
Nifurtimox is a nitroheterocyclic drug employed for treatment of trypanosomiases (Chagas disease and West African sleeping sickness); its use for certain cancers has also been assessed. Despite having been in the market for over 50 years, knowledge of nifurtimox is still fragmentary and incomplete. Relevant aspects of the chemistry and biology of nifurtimox are reviewed to summarize the current knowledge of this drug. These comprise its chemical synthesis and the preparation of some analogues, as well as its chemical degradation. Selected physical data and physicochemical properties are also listed, along with different approaches toward the analytical characterization of the drug, including electrochemical (polarography, cyclic voltammetry), spectroscopic (ultraviolet-visible, nuclear magnetic resonance, electron spin resonance), and single crystal X-ray diffractometry. The array of polarographic, ultraviolet-visible spectroscopic, and chromatographic methods available for the analytical determination of nifurtimox (in bulk drug, pharmaceutical formulations, and biological samples), are also presented and discussed, along with chiral chromatographic and electrophoretic alternatives for the separation of the enantiomers of the drug. Aspects of the drug likeliness of nifurtimox, its classification in the Biopharmaceutical Classification System, and available pharmaceutical formulations are detailed, whereas pharmacological, chemical, and biological aspects of its metabolism and disposition are discussed.
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Enfermedad de Chagas , Farmacia , Humanos , Nifurtimox/química , Nifurtimox/farmacología , Nifurtimox/uso terapéutico , Enfermedad de Chagas/tratamiento farmacológico , Preparaciones FarmacéuticasRESUMEN
Nifurtimox (NFX) is a nitrofuran derivative used to treat Chagas disease, a neglected disease caused by the protozoan Trypanosoma cruzi. The drug is very sparingly soluble in aqueous media and no other solid phases of NFX have been reported to date. The preparation of the amorphous mode of NFX is reported, as well as its characterization by hot stage microscopy, thermal (differential scanning calorimetry and thermogravimetric analysis), spectroscopic (solid state nuclear magnetic resonance, mid-infrared, and near-infrared), diffractometric and functional (powder dissolution rate) means. The stability of the new phase was investigated. This was characterized using thermal, spectroscopic, and diffractometric methods, finding out its spontaneous reversion to the crystalline state, as sign of instability. In addition, the amorphous material proved to be sensitive to temperature, pressure, and mechanical stress, all of which accelerated phase conversion. However, it was able to remain stable in a model polymeric amorphous solid dispersion with PEG 4000 for more than one month. An approach for monitoring the conversion of the amorphous phase to its crystalline counterpart under thermal stress by chemometric analysis of mid-infrared spectra at different temperatures is also disclosed.
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Nifurtimox , Estabilidad de Medicamentos , Cristalización , Rastreo Diferencial de Calorimetría , Temperatura , Solubilidad , Difracción de Rayos X , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
BACKGROUND: Parathyroid hormone-related peptide (PTHrP) plays a key role in the development and progression of many tumors. We found that in colorectal cancer (CRC) HCT116 cells, the binding of PTHrP to its receptor PTHR type 1 (PTHR1) activates events associated with an aggressive phenotype. In HCT116 cell xenografts, PTHrP modulates the expression of molecular markers linked to tumor progression. Empirical evidence suggests that the Met receptor is involved in the development and evolution of CRC. Based on these data, we hypothesized that the signaling pathway trigged by PTHrP could be involved in the transactivation of Met and consequently in the aggressive behavior of CRC cells. AIM: To elucidate the relationship among PTHR1, PTHrP, and Met in CRC models. METHODS: For in vitro assays, HCT116 and Caco-2 cells derived from human CRC were incubated in the absence or presence of PTHrP (1-34) (10-8 M). Where indicated, cells were pre-incubated with specific kinase inhibitors or dimethylsulfoxide, the vehicle of the inhibitors. The protein levels were evaluated by Western blot technique. Real-time polymerase chain reaction (RT-qPCR) was carried out to determine the changes in gene expression. Wound healing assay and morphological monitoring were performed to evaluate cell migration and changes related to the epithelial-mesenchymal transition (EMT), respectively. The number of viable HCT116 cells was counted by trypan blue dye exclusion test to evaluate the effects of irinotecan (CPT-11), oxaliplatin (OXA), or doxorubicin (DOXO) with or without PTHrP. For in vivo tests, HCT116 cell xenografts on 6-wk-old male N:NIH (S)_nu mice received daily intratumoral injections of PTHrP (40 µg/kg) in 100 µL phosphate-buffered saline (PBS) or the vehicle (PBS) as a control during 20 d. Humanitarian slaughter was carried out and the tumors were removed, weighed, and fixed in a 4% formaldehyde solution for subsequent treatment by immunoassays. To evaluate the expression of molecular markers in human tumor samples, we studied 23 specimens obtained from CRC patients which were treated at the Hospital Interzonal de Graves y Agudos Dr. José Penna (Bahía Blanca, Buenos Aires, Argentina) and the Hospital Provincial de Neuquén (Neuquén, Neuquén, Argentina) from January 1990 to December 2007. Seven cases with normal colorectal tissues were assigned to the control group. Tumor tissue samples and clinical histories of patients were analyzed. Paraffin-embedded blocks from primary tumors were reviewed by hematoxylin-eosin staining technique; subsequently, representative histological samples were selected from each patient. From each paraffin block, tumor sections were stained for immunohistochemical detection. The statistical significance of differences was analyzed using proper statistical analysis. The results were considered statistically significant at P < 0.05. RESULTS: By Western blot analysis and using total Met antibody, we found that PTHrP regulated Met expression in HCT116 cells but not in Caco-2 cells. In HCT116 cells, Met protein levels increased at 30 min (P < 0.01) and at 20 h (P < 0.01) whereas the levels diminished at 3 min (P < 0.05), 10 min (P < 0.01), and 1 h to 5 h (P < 0.01) of PTHrP treatment. Using an active Met antibody, we found that where the protein levels of total Met decreased (3 min, 10 min, and 60 min of PTHrP exposure), the status of phosphorylated/activated Met increased (P < 0.01) at the same time, suggesting that Met undergoes proteasomal degradation after its phosphorylation/activation by PTHrP. The increment of its protein level after these decreases (at 30 min and 20 h) suggests a modulation of Met expression by PTHrP in order to improve Met levels and this idea is supported by our observation that the cytokine increased Met mRNA levels at least at 15 min in HCT116 cells as revealed by RT-qPCR analysis (P < 0.05). We then proceeded to evaluate the signaling pathways that mediate the phosphorylation/ activation of Met induced by PTHrP in HCT116 cells. By Western blot technique, we observed that PP1, a specific inhibitor of the activation of the proto-oncogene protein tyrosine kinase Src, blocked the effect of PTHrP on Met phosphorylation (P < 0.05). Furthermore, the selective inhibition of the ERK 1/2 mitogen-activated protein kinase (ERK 1/2 MAPK) using PD98059 and the p38 MAPK using SB203580 diminished the effect of PTHrP on Met phosphorylation/activation (P < 0.05). Using SU11274, the specific inhibitor of Met activation, and trypan blue dye exclusion test, Western blot, wound healing assay, and morphological analysis with a microscope, we observed the reversal of cell events induced by PTHrP such as cell proliferation (P < 0.05), migration (P < 0.05), and the EMT program (P < 0.01) in HCT116 cells. Also, PTHrP favored the chemoresistance to CPT-11 (P < 0.001), OXA (P < 0.01), and DOXO (P < 0.01) through the Met pathway. Taken together, these findings suggest that Met activated by PTHrP participates in events associated with the aggressive phenotype of CRC cells. By immunohistochemical analysis, we found that PTHrP in HCT116 cell xenografts enhanced the protein expression of Met (0.190 ± 0.014) compared to tumors from control mice (0.110 ± 0.012; P < 0.05) and of its own receptor (2.27 ± 0.20) compared to tumors from control mice (1.98 ± 0.14; P < 0.01). Finally, assuming that the changes in the expression of PTHrP and its receptor are directly correlated, we investigated the expression of both Met and PTHR1 in biopsies of CRC patients by immunohistochemical analysis. Comparing histologically differentiated tumors with respect to those less differentiated, we found that the labeling intensity for Met and PTHR1 increased and diminished in a gradual manner, respectively (P < 0.05). CONCLUSION: PTHrP acts through the Met pathway in CRC cells and regulates Met expression in a CRC animal model. More basic and clinical studies are needed to further evaluate the PTHrP/Met relationship.
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Neoplasias Colorrectales , Proteína Relacionada con la Hormona Paratiroidea , Animales , Células CACO-2 , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Humanos , Irinotecán , Masculino , Ratones , Proteína Relacionada con la Hormona Paratiroidea/genética , Proteína Relacionada con la Hormona Paratiroidea/metabolismo , Proteína Relacionada con la Hormona Paratiroidea/farmacología , Azul de Tripano/farmacologíaRESUMEN
Albendazole is a benzimidazole-type active pharmaceutical ingredient, and one of the most effective broad-spectrum anthelminthic agents. The drug has two solid-state forms (ALB I and ALB II) which are desmotropes; both of them seem to be currently marketed. However, using the wrong crystalline solid form for formulation may have an undesired impact on the physicochemical and/or bioavailability properties of the drug product. In order to develop new, simple, and less expensive alternatives toward the determination of the level of albendazole ALB I in its mixtures with ALB II, both desmotropes were prepared, and properly characterized by spectroscopic [solid-state nuclear magnetic resonance and near infrared (NIR)] and diffractometric (powder X-ray diffraction) methods. Then, the NIR and attenuated total reflectance-mid infrared (ATR-MIR) spectra of both forms were conveniently pre-treated and employed for the development and optimization of partial least squares (PLS)-potentiated quantification models (NIR/PLS and ATR-MIR/PLS). The latter were also subjected to validation (accuracy, precision, limits of detection and quantification, etc.) and further used to assess the level of the unwanted ALB II form in the bulk drug. The NIR/PLS method displayed the most satisfactory characteristics, including a limit of quantitation interval of 3.6 ± 1 %w/w; it outperformed both, the ATR-MIR/PLS counterpart (limit of quantitation interval of 14.0 ± 3.4 %w/w) and a previously published and more demanding Raman/PLS alternative.
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Albendazol , Análisis de los Mínimos Cuadrados , Espectroscopía de Resonancia Magnética , Polvos , Difracción de Rayos XRESUMEN
Colorectal cancer (CRC) remains one of the leading causes of mortality from malignant diseases worldwide. In general terms, CRC presents high heterogeneity due to the influence of different genetic and environmental factors; also, the neoplastic cells are strongly influenced by the extracellular matrix and several surrounding cells, known together as the tumor microenvironment (TME). Bidirectional communication takes place between the tumor and the TME through the release of autocrine and paracrine factors. Parathyroid hormone-related peptide (PTHrP) is a cytokine secreted by a wide variety of tissues and is able to regulate several cellular functions both in physiological as well as in pathological processes. It exerts its effects as a paracrine/autocrine factor, although its mode of action is mainly paracrine. It has been shown that this peptide is expressed by several tumors and that the tumor secretion of PTHrP is responsible for the malignant humoral hypercalcemia. Eight years ago, when our research group started studying PTHrP effects in the experimental models derived from intestinal tumors, the literature available at the time addressing the effects of PTHrP on colorectal tumors was limited, and no articles had been published regarding to the paracrine action of PTHrP in CRC cells. Based on this and on our previous findings regarding the role of PTH in CRC cells, our purpose in recent years has been to explore the role of PTHrP in CRC. We analyzed the behavior of CRC cells treated with exogenous PTHrP, focalizing in the study of the following events: Survival, cell cycle progression and proliferation, migration, chemoresistance, tumor-associated angiogenesis, epithelial to mesenchymal transition program and other events also associated with invasion, such us the induction of cancer stem cells features. This work summarizes the major findings obtained by our investigation group using in vitro and in vivo CRC models that evidence the participation of PTHrP in the acquisition of an aggressive phenotype of CRC cells and the molecular mechanisms involved in these processes. Recently, we found that this cytokine induces this malignant behavior not only by its direct action on these intestinal cells but also through its influence on cells derived from TME, promoting a communication between CRC cells and surrounding cells that contributes to the molecular and morphological changes observed in CRC cells. These investigations establish the basis for our next studies in order to address the clinical applicability of our findings. Recognizing the factors and mechanisms that promote invasion in CRC cells, evasion to the cytotoxic effects of current CRC therapies and thus metastasis is decisive for the identification of new markers with the potential to improve early diagnosis and/or to predict prognosis, to predetermine drug resistance and to provide treatment guidelines that include targeted therapies for this disease.
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Neoplasias Colorrectales , Hipercalcemia , Transición Epitelial-Mesenquimal , Humanos , Hormona Paratiroidea , Proteína Relacionada con la Hormona Paratiroidea , Fenotipo , Microambiente TumoralRESUMEN
The Drosophila repleta group comprises more than one hundred species that inhabit several environments in the Neotropics and use different hosts as rearing and feeding resources. Rather homogeneous in their external morphology, they are generally distinguished by the male genitalia, seemingly their fastest evolving morphological trait, constituting an excellent model to study patterns of genital evolution in the context of a continental adaptive radiation. Although much is known about the evolution of animal genitalia at population level, surveys on macroevolutionary scale of this phenomenon are scarce. This study used a suite of phylogenetic comparative methods to elucidate the macroevolutionary patterns of genital evolution through deep time and large continental scales. Our results indicate that male genital size and some aspects of shape have been evolving by speciational evolution, probably due to the microevolutionary processes involved in species mate recognition. In contrast, several features of the aedeagus shape seemed to have evolved in a gradual fashion, with heterogeneous evolutionary phenotypic rates among clades. In general, the tempo of the evolution of aedeagus morphology was constant from the origin of the group until the Pliocene, when it accelerated in some clades that diversified mainly in this period. The incidence of novel ecological conditions in the tempo of aedeagus evolution and the relationship between species mate recognition and speciation in the Drosophila repleta group are discussed.
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Drosophila , Genitales Masculinos , Animales , Evolución Biológica , Drosophila/genética , Genitales , Masculino , Fenotipo , FilogeniaRESUMEN
Parathyroid hormone-related peptide (PTHrP) exerts its effects on cells derived from colorectal cancer (CRC) and tumor microenvironment and is involved in processes requiring the epithelial-mesenchymal transition (EMT). Here, we report that PTHrP modulates factors expression and morphological changes associated with EMT in HCT116 cells from CRC. PTHrP increased the protein expression of SPARC, a factor involved in EMT, in HCT116 cells but not in Caco-2 cells also from CRC but with less aggressiveness. PTHrP also increased SPARC expression and its subsequent release from endothelial HMEC-1 cells. The conditioned media of PTHrP-treated HMEC-1 cells induced early changes related to EMT in HCT116 cells. Moreover, SPARC treatment on HCT116 cells potentiated PTHrP modulation in E-cadherin expression and cell migration. In vivo PTHrP also increased SPARC expression and decreased E-cadherin expression. These results suggest a novel PTHrP action on CRC progression involving the microenvironment in the modulation of events associated with EMT.
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Antígenos CD/metabolismo , Cadherinas/metabolismo , Neoplasias del Colon/patología , Células Endoteliales/citología , Osteonectina/metabolismo , Proteína Relacionada con la Hormona Paratiroidea/metabolismo , Regulación hacia Arriba , Animales , Células CACO-2 , Línea Celular , Movimiento Celular , Proliferación Celular , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Medios de Cultivo Condicionados/química , Progresión de la Enfermedad , Células Endoteliales/metabolismo , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Humanos , Ratones , Trasplante de Neoplasias , Osteonectina/genética , Proteína Relacionada con la Hormona Paratiroidea/genética , Microambiente TumoralRESUMEN
Among different Candida species triggering vaginal candidiasis, Candida albicans is the most predominant yeast. It is commonly treated using azole drugs such as Tioconazole (TIO) and Econazole (ECO). However, their low water solubility may affect their therapeutic efficiency. Therefore, the aim of this research was to produce a novel chitosan nanocapsule based delivery system comprising of TIO or ECO and to study their suitability in vaginal application. These systems were characterized by their physicochemical properties, encapsulation efficiency, in vitro release, storage stability, cytotoxicity, and in vitro biological activity. Both nanocapsules loaded with TIO (average hydrodynamic size of 146.8 ± 0.8 nm, zeta potential of +24.7 ± 1.1 mV) or ECO (average hydrodynamic size of 127.1 ± 1.5 nm, zeta potential of +33.0 ± 1.0 mV) showed excellent association efficiency (99% for TIO and 87% for ECO). The analysis of size, polydispersity index, and zeta potential of the systems at 4, 25, and 37 °C (over a period of two months) showed the stability of the systems. Finally, the developed nanosystems presented fungicidal activity against C. albicans at non-toxic concentrations (studied on model human skin cells). The results obtained from this study are the first step in the development of a pharmaceutical dosage form suitable for the treatment of vaginal candidiasis.
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Antifúngicos/administración & dosificación , Quitosano/química , Portadores de Fármacos/química , Nanopartículas/química , Antifúngicos/química , Candida albicans/efectos de los fármacos , Fenómenos Químicos , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Estabilidad de Medicamentos , Econazol/administración & dosificación , Econazol/química , Imidazoles/administración & dosificación , Imidazoles/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Nanocápsulas/química , Nanopartículas/ultraestructuraRESUMEN
The assessment of polymorphism is a problematical issue for regulatory agencies, because variations among crystalline forms of active pharmaceutical ingredient (API) can lead to changes in the efficacy and safety of formulated product. Such conversions are very hard to be detected, thus, the development of techniques for the identification, characterization and quantification of polymorphs results essential in all stages of the manufacturing process. The presence of excipients in formulated products may change the crystal stability of an API, by catalyzing a polymorphic transformation or stabilizing the less stable form. As paradox, all suitable analytical techniques (spectroscopies, thermal analysis, NMR and DRX, and others) for polymorphic analysis are affected by excipients. A deep understanding of the polymorphism-excipient relationship is in full accordance with Quality by Design (QbD) paradigm, the systematic approach focused in quality building into a product based in the full understanding of the products and process. In this work, a novel approach based on thermal stress, MIR monitoring, multivariate curve resolution with alternating least squares (MCR-ALS) and kinetic analysis was developed and applied to monitor polymorphism behavior of model API in formulated products. Commercial tablets, physical mixtures and commercial API, were processed and analyzed under the proposed approach. Commercial tablets of MFA revealed a fast conversion to Form II, contrasting to the behavior of the pure API. Physical mixtures showed similar behavior to commercial tablets, thus reduction in transformation times was related to MFA-excipients physical interaction, even at surface level. Calorimetric studies support the conclusion obtained. The developed approach could be extended to others APIs and other stress sources (humidity, solvents, mechanical forces and its combinations), being a valuable tool for QbD environment.
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Excipientes/química , Ácido Mefenámico/química , Química Farmacéutica/métodos , Cristalización/métodos , Humedad , Cinética , Análisis de los Mínimos Cuadrados , Comprimidos/químicaRESUMEN
Tioconazole (TCZ), a broad-spectrum antifungal agent, has significant activity against Candida albicans and other Candida species, and therefore, it is indicated for the topical treatment of superficial mycoses. The main goal of this work is to report an exhaustive identification and characterization procedure to improve and facilitate the online quality control and continuous process monitoring of TCZ in bulk material and loaded in two different dosage forms: ovules and nail lacquer. The methodologies were based on thermal (differential scanning calorimetry (DSC), melting point, and thermogravimetry (TG)), spectroscopic (ultraviolet (UV), Raman, near infrared (NIR), infrared spectroscopy coupled to attenuated total reflectance (FTIR-ATR), and nuclear magnetic resonance (NMR)), microscopic and X-ray diffraction (XRD). The TCZ bulk powder showed a high crystallinity, as observed by XRD, with a particles size distribution (3-95⯵m) resolved by microscopic measurements. TCZ melting point (82.8⯰C) and a degradation peak centered at 297.8⯰C were obtained by DSC and DTG, respectively. An unambiguous structure elucidation of TCZ was obtained by mono- and two- dimensional 1H and 13C NMR spectral data analysis. The FTIR-ATR, Raman and NIR spectra of both the raw material and the commercial products were analyzed and their characteristic bands were tabulated. The best methods for TCZ identification in ovules were DSC, TG, XRD, NIR and Raman, while NIR and FTIR-ATR were the most appropriate techniques to analyze it in the nail lacquer. DSC, TG, DRX, Raman, FTIR-ATR and NIR spectroscopy are effective techniques to be used in online process analysis, because they do not require sample preparation, and they are considerably sensitive to analyze complex samples.
RESUMEN
Vaginal candidiasis is considered a frequent opportunistic mucosal infection and the second most common cause of vaginitis after bacterial vaginosis. In this work, different vaginal films based on chitosan, hydroxypropyl methylcellulose and blends of these polymers containing tioconazole, were developed and thoroughly characterized to improve the conventional therapeutics of vaginal candidiasis. Mechanical properties, swelling, adhesiveness, morphology, antifungal activity, hemocompatibility and cytotoxicity were evaluated. The drug solid state in the films was analyzed by thermal and X-ray diffraction analysis. Films showed homogeneous surfaces and presented similar mechanical properties and adhesiveness. Time-kill studies displayed that films were more active than both tioconazole pure drug and traditional tioconazole ovule against Candida albicans, which is probably related to the fact that tioconazole is in amorphous state inside the films. Although all formulations proved to be hemocompatible, films based only on chitosan exhibited a certain degree of cytotoxicity and therefore they should be avoided. The system based on chitosan-hydroxypropyl methylcellulose with 40% PEG 400 as plasticizer presented fast antimicrobial activity as well as the lowest swelling. Additionally, this formulation did not produce substantial hemolytic and cytotoxic effects, indicating that films based on chitosan-hydroxypropyl methylcellulose could be a promising alternative dosage form for the treatment of vaginal candidiasis.
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Antifúngicos/administración & dosificación , Quitosano/química , Derivados de la Hipromelosa/química , Imidazoles/administración & dosificación , Adhesividad , Antifúngicos/química , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Candidiasis Vulvovaginal/tratamiento farmacológico , Línea Celular Tumoral , Química Farmacéutica/métodos , Portadores de Fármacos/química , Femenino , Humanos , Imidazoles/química , Imidazoles/farmacología , Plastificantes/química , Polietilenglicoles/química , Difracción de Rayos XRESUMEN
Nimodipine (NIM) is a calcium channel-blocking agent, which in the solid state exhibits two crystalline modifications, Mode I and Mode II. The first one is a racemic mixture, while the second is a conglomerate. Because the drug has poor aqueous solubility and Mode I is twice as soluble as Mode II, the former is widely preferred for the development of pharmaceutical forms. In order to study the effect of thermal stimuli on the behavior of NIM, an analytical method was developed coupling ATR-FTIR spectroscopy to Multivariate Curve Resolution with Alternating Least Squares (MCR-ALS). The method allowed to monitor the transformations of each polymorph, their respective mixtures and commercial samples, during the thermal treatment. It was observed that Mode II experienced changes during the experiments and the chemometric technique provided the abundance profile and the pure spectra of the different species involved. In this way, it was established that Mode II has two transitions, at 116.8⯰C and 131.9⯰C, which reflect that Mode II is first transformed into Mode I, which then melts. The liquid phase solidifies to give an amorphous (AM) vitreous solid, which does not revert to the crystalline state. The analysis of a commercial sample of NIM exhibited the similar transformations than Mode II; however, a pronounced decrease was noted in the first transition temperature (95⯰C), whereas the second remained essentially unchanged (131.6⯰C). This could be a result of the presence of mixtures of Mode I and Mode II (0.32:0.68) in the bulk solid, as confirmed by the analysis of a physical mixture of crystals of Modes I and II. Therefore, it was concluded that the developed ATR-FTIR/MCR-ALS method is suitable for the detailed analysis of the crystalline forms of NIM in bulk drug and enables de study of their possible thermally promoted interconversions.
Asunto(s)
Bloqueadores de los Canales de Calcio/química , Composición de Medicamentos/normas , Nimodipina/química , Química Farmacéutica , Cristalización , Almacenaje de Medicamentos , Análisis de los Mínimos Cuadrados , Control de Calidad , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier/instrumentación , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Temperatura de Transición , AguaRESUMEN
The understanding of materials and processes is a requirement when it comes to build quality into pharmaceutical products. This can be achieved through the development of rapid, efficient and versatile analytical methods able to perform qualification or quantification tasks along the manufacturing and control process. Process monitoring, capable of providing reliable real-time insights into the processes performance during the manufacturing of solid dosage forms, are the key to improve such understanding. In response to these demands, in recent times multivariate chemometrics algorithms have been increasingly associated to different analytical techniques, mainly vibrational spectroscopies [Raman, mid-infrared (MIR), near-infrared (NIR)], but also ultraviolet-visible (UV-vis) spectroscopy, X-ray powder diffraction and other methodologies. The resulting associations have been applied to the characterization and evaluation of different aspects of pharmaceutical materials at the solid state. This review examines the different scenarios where these methodological marriages have been successful. The list of analytical problems and regulatory demands solved by chemometrics analysis of solid-state multivariate data covers the whole manufacturing and control processes of both, active pharmaceutical ingredients in bulk and in their drug products. Hence, these combinations have found use in monitoring the crystallization processes of drugs and supramolecular drug associations (co-crystals, co-amorphous and salts), to access the correct crystal morphology, particle size, solubility and dissolution properties. In addition, they have been applied to identify and quantitate specific compounds, mainly active pharmaceutical ingredients in complex solid state mixtures. This included drug stability against different stimuli, solid-state transformations, or detection of adulterated or fraudulent medicines. The use of chemometrics-assisted analytical methods as part of the modern concept of process analytical technology, where every process step of every product batch from raw materials to final product must take place in a controlled manner is discussed. Finally, but no less important, the application of chemometrics methods to chemical imaging, aiming to extract spatial and compositional information is also revised.
Asunto(s)
Química Farmacéutica/métodos , Preparaciones Farmacéuticas/análisis , Tecnología Farmacéutica/métodos , Cristalización/métodos , Preparaciones Farmacéuticas/química , Espectroscopía Infrarroja Corta/métodos , Vibración , Difracción de Rayos X/métodosRESUMEN
Current regulations command to properly characterize pharmaceutically relevant solid systems. Chemometrics comprise a range of valuable tools, suitable to process large amounts of data and extract valuable information hidden in their structure. This review aims to detail the results of the fruitful association between analytical techniques and chemometrics methods, focusing on those which help to gain insight into the characteristics of drug polymorphism as an important aspect of the solid state of bulk drugs and drug products. Hence, the combination of Raman, terahertz, mid- and near- infrared spectroscopies, as well as instrumental signals resulting from X-ray powder diffraction, 13C solid state nuclear magnetic resonance spectroscopy and thermal methods with quali-and quantitative chemometrics methodologies are examined. The main issues reviewed, concerning pharmaceutical drug polymorphism, include the use of chemometrics-based approaches to perform polymorph classification and assignment of polymorphic identity, as well as the determination of given polymorphs in simple mixtures and complex systems. Aspects such as the solvation/desolvation of solids, phase transformation, crystallinity and the recrystallization from the amorphous state are also discussed. A brief perspective of the field for the next future is provided, based on the developments of the last decade and the current state of the art of analytical instrumentation and chemometrics methodologies.
Asunto(s)
Química Farmacéutica/métodos , Cristalización/métodos , Espectroscopía de Resonancia Magnética/métodos , Preparaciones Farmacéuticas/análisis , Espectrometría Raman/métodos , Preparaciones Farmacéuticas/química , Difracción de Rayos X/métodosRESUMEN
Parathyroid hormone-related peptide (PTHrP) is associated with several human cancers such as colon carcinoma. This disease is a complex multistep process that involves enhanced cell cycle progression and migration. Recently we obtained evidence that in the human colorectal adenocarcinoma Caco2 cells, exogenous PTHrP increases the proliferation and positively modulates cell cycle progression via ERK1/2, p38 MAPK and PI3K. The purpose of this study was to explore if the serine/threonine kinase RSK, which is involved in the progress of many cancers and it is emerging as a potential therapeutic target, mediates PTHrP effects on cancer colon cells. Western blot analysis revealed that PTHrP increases RSK phosphorylation via ERK1/2 signaling pathway but not through p38 MAPK. By performing subcellular fractionation, we found that the peptide also induces the nuclear localization of activated RSK, where many of its substrates are located. RSK participates in cell proliferation, in the upregulation of cyclin D1 and CDK6 and in the downregulation of p53 induced by PTHrP. Wound healing and transwell filter assays revealed that cell migration increased after PTHrP treatment. In addition, the hormone increases the protein expression of the focal adhesion kinase FAK, a regulator of cell motility. We observed that PTHrP induces cell migration and modulates FAK protein expression through ERK/RSK signaling pathway but not via p38 MAPK pathway. Finally, in vivo studies revealed that the hormone activates RSK in xenografts tumor. Taken together, our findings provide new insights into the deregulated cell cycle and migration that is characteristic of tumor intestinal cells.