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1.
Mater Today Bio ; 8: 100083, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33294837

RESUMO

The fast and non-invasive detection of odors and volatile organic compounds (VOCs) by gas sensors and electronic noses is a growing field of interest, mostly due to a large scope of potential applications. Additional drivers for the expansion of the field include the development of alternative and sustainable sensing materials. The discovery that isolated cross-linked polymeric structures of suberin spontaneously self-assemble as a film inspired us to develop new sensing composite materials consisting of suberin and a liquid crystal (LC). Due to their stimuli-responsive and optically active nature, liquid crystals are interesting probes in gas sensing. Herein, we report the isolation and the chemical characterization of two suberin types (from cork and from potato peels) resorting to analyses of gas chromatography-mass spectrometry (GC-MS), solution nuclear magnetic resonance (NMR), and X-ray photoelectron spectroscopy (XPS). The collected data highlighted their compositional and structural differences. Cork suberin showed a higher proportion of longer aliphatic constituents and is more esterified than potato suberin. Accordingly, when casted it formed films with larger surface irregularities and a higher C/O ratio. When either type of suberin was combined with the liquid crystal 5CB, the ensuing hybrid materials showed distinctive morphological and sensing properties towards a set of 12 VOCs (comprising heptane, hexane, chloroform, toluene, dichlormethane, diethylether, ethyl acetate, acetonitrile, acetone, ethanol, methanol, and acetic acid). The optical responses generated by the materials are reversible and reproducible, showing stability for 3 weeks. The individual VOC-sensing responses of the two hybrid materials are discussed taking as basis the chemistry of each suberin type. A support vector machines (SVM) algorithm based on the features of the optical responses was implemented to assess the VOC identification ability of the materials, revealing that the two distinct suberin-based sensors complement each other, since they selectively identify distinct VOCs or VOC groups. It is expected that such new environmentally-friendly gas sensing materials derived from natural diversity can be combined in arrays to enlarge selectivity and sensing capacity.

2.
Mater Today Bio ; 5: 100039, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32211605

RESUMO

Suberin, a plant polyester, consists of polyfunctional long-chain fatty acids and glycerol and is an intriguing candidate as a novel antimicrobial material. We purified suberin from cork using ionic-liquid catalysis during which the glycerol bonds that ensure the polymeric nature of suberin remained intact or were only partially cleaved-yielding the closest to a native configuration reported to date. The chemistry of suberin, both in situ (in cryogenically ground cork) and ex situ (ionic-liquid extracted), was elucidated using high-resolution one- and two-dimensional solution-state NMR analyses. Centrifugation was used to isolate suberin particles of distinct densities and their monomeric composition, assembly, and bactericidal effect, inter alia, were assessed. Analysis of the molecular structure of suberin revealed the relative abundance of linear aliphatic vs. acylglycerol esters, comprising all acylglycerol configurations and the amounts of total carbonyls (C[bond, double bond]O), free acid end groups (COOH), OH aliphatics, and OH aromatics. Suberin centrifuged fractions revealed generic physiochemical properties and monomeric composition â€‹and self-assemble into polygonal structures that display distinct degrees of compactness when lyophilized. Suberin particles-suberinsomes-display bactericidal activity against major human pathogenic bacteria. Fingerprinting the multifunctionality of complex (plant) polyesters such as suberin allows for the identification of novel polymer assemblies with significant value-added properties.

3.
Curr Cancer Drug Targets ; 18(3): 222-230, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28460619

RESUMO

Cancer is a global health issue that impairs the life quality of patients and origins thousands of deaths annually worldwide. Six-transmembrane epithelial antigen of the prostate (STEAP1) was identified to be overexpressed in several types of cancers, namely in prostate cancer (PCa). Considering its secondary structure, associated with its location in the cell membrane, has been suggested a role in intercellular communication between tumour cells. Taking into account its high specificity and overexpression in human cancers, STEAP1 is nowadays a promising candidate to be imposed as a therapeutic target. Several strategies have been developed during the last few years for targeting STEAP1, including antibody-drug conjugates, monoclonal antibodies (mAbs), DNA vaccines and small noncoding RNAs (ncRNAs). This review presents the current knowledge about STEAP1 protein expression in human tissues, its biochemical properties and targeting strategies with the purpose to evaluate its potential as therapeutic agent for cancer.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Oxirredutases/antagonistas & inibidores , Animais , Antígenos de Neoplasias/imunologia , Humanos , Neoplasias/imunologia , Neoplasias/metabolismo , Oxirredutases/imunologia , Transporte Proteico
4.
Anim Genet ; 46(4): 452-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26153924

RESUMO

In the course of human migrations, domestic animals often have been translocated to islands with the aim of assuring food availability. These founder events are expected to leave a genetic footprint that may be recognised nowadays. Herewith, we have examined the mitochondrial diversity of goat populations living in the Canarian and Balearic archipelagos. Median-joining network analysis produced very distinct network topologies for these two populations. Indeed, a majority of Canarian goats shared a single ancestral haplotype that segregated in all sampled islands, suggesting a single founder effect followed by a stepping-stone pattern of diffusion. This haplotype also was present in samples collected from archaeological assemblies at Gran Canaria and Lanzarote, making evident its widespread distribution in ancient times. In stark contrast, goats from Majorca and Ibiza did not share any mitochondrial haplotypes, indicating the occurrence of two independent founder events. Furthermore, in Majorcan goats, we detected the segregation of the mitochondrial G haplogroup that has only been identified in goats from Egypt, Iran and Turkey. This finding suggests the translocation of Asian and/or African goats to Majorca, possibly as a consequence of the Phoenician and Carthaginian colonisations of this island.


Assuntos
DNA Mitocondrial/genética , Efeito Fundador , Genética Populacional , Cabras/genética , Animais , Animais Domésticos/genética , Pool Gênico , Deriva Genética , Haplótipos , Ilhas , Dados de Sequência Molecular , Análise de Sequência de DNA , Espanha
7.
Actas urol. esp ; 32(10): 1035-1036, nov.-dic. 2008. ilus
Artigo em Es | IBECS | ID: ibc-69621

RESUMO

El quiste de Tarlov o quiste perineural son lesiones de las raíces nerviosas localizadas a nivel de la región sacra y de etiología incierta. La mayoría de estos quistes permanecen asintomáticos y carecen de relevancia clínica. Los quistes sintomáticos son infrecuentes y los síntomas más habituales son el dolor y las radiculopatías. Nosotros presentamos el caso de una mujer de 53 años con un quiste de Tarlov sintomático ( síndrome de frecuencia y urgencia miccional) que tras el tratamiento quirúrgico presenta una mejoría clínica importante (AU)


Tarlov cysts or perineural cyst are lesions of the nerve roots located at the sacral level and uncertain etiology. Most of these cysts remain asymptomatic with no clinical relevance. The symptomatic cysts are uncommon and the usual symptoms are pain or radiculopathy. We report the case of a 53 year old woman with a symptomatic cyst (with a history of frequency and urgency syndrom), that disappears after surgery (AU)


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Cistos Aracnóideos/complicações , Cistos Aracnóideos/diagnóstico , Radiculopatia/complicações , Radiculopatia/diagnóstico , Urografia/métodos , Laminectomia/métodos , Fatores de Risco , Cistos Aracnóideos , Urografia/normas , Urografia/tendências , Urografia , Qualidade de Vida
10.
Arch. esp. urol. (Ed. impr.) ; 61(4): 544-546, mayo 2008. ilus
Artigo em Es | IBECS | ID: ibc-64503

RESUMO

Objetivo: Presentar un nuevo caso de melanoma localizado en el glande. Métodos/Resultados: Presentamos en este artículo el caso de un paciente diagnosticado y tratado en nuestro servicio, describiendo su forma de presentación así como su manejo terapéutico. Conclusiones: El melanoma de localización peneana es una forma infrecuente de presentación de este tipo de tumores cutáneos. Hacemos especial hincapié en su diagnóstico, presentación clínica y manejo terapéutico, ya que se trata de una neoplasia que requiere un diagnóstico y tratamiento precoces debido a su pronta diseminación metastásica (AU)


Objective: To report one case of melanoma of the glans penis. Methods/Results: We present the case of a patient diagnosed and treated in our department describing diagnosis and therapeutic management. Conclusions: Melanoma of the penis is an uncommon presentation form of this kind of cutaneous tumor. We especially emphasize its diagnosis, clinical presentation and therapeutic management due to its prompt metastatic dissemination requiring early diagnosis and treatment (AU)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Melanoma/complicações , Melanoma/diagnóstico , Metástase Neoplásica/diagnóstico , Metástase Neoplásica/patologia , Prostatectomia/métodos , Biópsia/métodos , Neoplasias Penianas/complicações , Imunoterapia/métodos , Interferons/uso terapêutico , Excisão de Linfonodo/métodos , Adenocarcinoma/complicações , Neoplasias Penianas/diagnóstico , Adenocarcinoma/diagnóstico , Neoplasias Penianas/patologia , Pênis/patologia , Pênis/cirurgia , Pênis
11.
Actas Urol Esp ; 32(10): 1035-6, 2008.
Artigo em Espanhol | MEDLINE | ID: mdl-19143297

RESUMO

Tarlov cysts or perineural cyst are lesions of the nerve roots located at the sacral level and uncertain aetiology. Most of these cysts remain asymptomatic with no clinical relevance. The symptomatic cysts are uncommon and the usual symptoms are pain or radiculopathy. We report the case of a 53-year-old woman witha symptomatic cyst (with a history of frequency and urgency syndrom), that disappears after surgery.


Assuntos
Cistos de Tarlov/complicações , Cistos de Tarlov/cirurgia , Doenças da Bexiga Urinária/etiologia , Doenças da Bexiga Urinária/cirurgia , Transtornos Urinários/etiologia , Transtornos Urinários/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade
14.
Drug Dev Ind Pharm ; 26(7): 785-90, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10872100

RESUMO

The evaluation of the biopharmaceutical quality of omeprazole enteric-coated products (granules in capsules) with respect to its dissolution characteristics is not specifically regulated in any of the most common official pharmacopoeia. USP 23 includes a general monograph for enteric-coated products. This paper reports the evaluation of the medium pH effect on the dissolution rates of omeprazole from four omeprazole-containing products of different manufacturers. It is concluded that the USP 23 recommended dissolution procedure for enteric-coated products is not suitable due to the degradation of omeprazole under such conditions. Furthermore, the medium with pH 8.0 showed different dissolution rates not observed at pH 7.4, allowing discrimination between products of different manufacturers.


Assuntos
Antiulcerosos/administração & dosagem , Química Farmacêutica/métodos , Omeprazol/administração & dosagem , Administração Oral , Avaliação de Medicamentos/métodos , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Comprimidos com Revestimento Entérico
15.
Int J Pharm ; 182(1): 41-7, 1999 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-10332073

RESUMO

Permeation of caffeine through human skin and artificial membranes (mounted in modified Franz type diffusion cells) was evaluated, either from saturated solutions or from commercially available topical formulations (all containing 3% caffeine). Data interpretation of the caffeine diffusion through human skin does not implicate transfer through pores despite caffeine being a relatively polar molecule. No correlation was found between transfer though the synthetic membranes (cellulose acetate impregnated with isopropyl myristate and silicone rubber soaked in isopropyl myristate) and that observed through skin. The synthetic membranes can be used for assessing product performance in quality assurance but will give little indication of its performance in vivo. The study investigated the percutaneous permeation of caffeine through human skin in order to obtain a mechanistic interpretation of its route of permeation. Synthetic membranes were also examined to determine if they could be used as models for human skin. Different commercial formulations investigated to determine the significance of enhancement strategies.


Assuntos
Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Membranas Artificiais , Administração Tópica , Cafeína/química , Cafeína/farmacocinética , Celulose/análogos & derivados , Estimulantes do Sistema Nervoso Central/química , Estimulantes do Sistema Nervoso Central/farmacocinética , Química Farmacêutica , Difusão , Humanos , Técnicas In Vitro , Cinética , Permeabilidade , Silício , Pele/metabolismo , Absorção Cutânea , Solubilidade , Soluções
16.
Eur J Pharm Sci ; 7(4): 311-5, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9971914

RESUMO

Omeprazole, a proton pump inhibitor, effectively suppresses the gastric acid secretion in the parietal cells of the stomach. Several previously published papers focus on the pharmacokinetics of the drug and its interactions with physiological aspects or with other drugs. The increasing number of omeprazole containing products available in the market, raises questions of therapeutic equivalence and/or generic substitution. The bioequivalence evaluation between two or more formulations provides information about in vivo performance. In a favorable decision regarding bioequivalence, the products are considered to have a similar therapeutic efficacy when used under the same therapeutic conditions. This paper reports the design, results and some important aspects involved in a bioequivalence study between two solid oral formulations from different manufacturers. Some important findings were the high intra-subject variability observed for Cmax and the variability observed between subject profiles, probably caused by the multi-unit type of formulations studied.


Assuntos
Antiulcerosos/administração & dosagem , Antiulcerosos/farmacologia , Omeprazol/administração & dosagem , Omeprazol/farmacocinética , Adulto , Área Sob a Curva , Estudos Cross-Over , Feminino , Meia-Vida , Humanos , Masculino , Modelos Biológicos , Comprimidos com Revestimento Entérico , Equivalência Terapêutica
17.
J Pharm Biomed Anal ; 14(5): 617-22, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8738192

RESUMO

An isocratic high-performance liquid chromatographic method is described for the quantitative analysis of low concentrations of apovincaminic acid (AVA) in blood plasma. AVA, interfering plasma components and primidone (used as the internal standard) were separated on a reversed-phase column of LiChrospher 60 RP-Select B (125 mm x 3 mm i.d.; 5 microns) (Merck). A UV-Vis detector was used at a wavelength of 254 nm. Each chromatographic separation was completed in 14 min and the results showed a relative recovery which varied between 95.9 and 116%, a good overall precision (relative standard deviation, 7.00%) and sensitivity over a linear range of 5.00-300 ng ml-1 (R = 0.999) for AVA in plasma. The method was applied to the analysis of plasma samples obtained from healthy subjects treated with one single oral dose of 20 mg of vinpocetine. The results indicate the method to be suitable for pharmacokinetic studies.


Assuntos
Vasodilatadores/sangue , Alcaloides de Vinca/sangue , Administração Oral , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão/métodos , Preparações de Ação Retardada , Humanos , Sensibilidade e Especificidade , Comprimidos , Vasodilatadores/farmacocinética , Alcaloides de Vinca/farmacocinética
18.
Eur J Drug Metab Pharmacokinet ; 20(4): 275-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8983932

RESUMO

The influence of an antacid on droxicam pharmacokinetics was investigated in 12 healthy male volunteers. A two way cross-over study was performed after the oral administration of 20 mg of droxicam (Ombolan capsules) and droxicam together with an antacid (Mucal powder). The plasma concentrations of piroxicam, the active moiety of droxicam, were determined by a high-performance liquid chromatographic method. The pharmacokinetic parameter values (mean +/- RSD) of piroxicam after administration of droxicam alone were: AUC0-->infinity = 125.5 +/- 25.1 micrograms.h/l, Cmax = 2.08 +/- 19.9 micrograms/l, tmax = 7.08 +/- 36.8 h and t1/2 = 46.3 +/- 27.0 h. Following administration of droxicam together with the antacid the values obtained for the same parameters were: AUC0-->infinity = 135.1 +/- 24.1 micrograms.h/l. Cmax = 1.85 +/- 23.9 micrograms/l, tmax = 8.17 +/- 34.9 h and t1/2 = 52.0 +/- 22.4 h. These results indicate that concurrent administration of the antacid does not significantly change the bioavailability and pharmacokinetics of droxicam.


Assuntos
Compostos de Alumínio/farmacologia , Antiácidos/farmacologia , Anti-Inflamatórios não Esteroides/farmacocinética , Compostos de Magnésio/farmacologia , Piroxicam/sangue , Piridinas/farmacocinética , Silicatos/farmacologia , Administração Oral , Adulto , Análise de Variância , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/sangue , Disponibilidade Biológica , Estudos Cross-Over , Humanos , Masculino , Piridinas/administração & dosagem , Piridinas/sangue
20.
Eur J Surg Oncol ; 20(5): 592-4, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7926067

RESUMO

Solitary extramedullary plasmacytoma (EMP) of the rectum is an exceedingly rare entity. We report the fourth case of solitary EMP of the rectum and the first one treated by endoscopic polypectomy and radiotherapy. The patient showed no signs of local recurrence or dissemination of the disease after a 12-month follow-up. This case report is presented along with a review of the literature dealing with solitary plasmacytomas of the rectum.


Assuntos
Plasmocitoma/terapia , Proctoscopia , Neoplasias Retais/terapia , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Humanos , Plasmocitoma/radioterapia , Plasmocitoma/cirurgia , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia
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