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OBJECTIVES: Norepinephrine is usually used in emergency situations such as in intensive care units (ICUs) for the restoration of blood pressure. The objective was to study the stability of highly-concentrated solutions of norepinephrine at 0.50mg/mL and 1.16mg/mL, diluted in glucose 5% (G5%) in polypropylene syringes, protected or not from light, up to 48h. MATERIALS AND METHODS: Chemical stability was analysed by high-performance liquid chromatography coupled to photodiode array detection at each time of the analysis. The method was validated according to the International Conference on Harmonisation Q2(R1). Physical stability was evaluated by visual and subvisual inspection. Three syringes for each condition were prepared. At each time of the analysis, three samples were analysed for each syringe. pH values were evaluated at each moment of the analysis. RESULTS: Solutions of norepinephrine at 0.50 and 1.16mg/mL, diluted in G5%, with or without protection from light, retained more than 95.0% of the initial concentration after a 48-hour storage at 20-25°C. No visual and subvisual modification occured during the stability study. No degradation product appearing during the stressed degradation was observed during the study but an additional peak with a relative retention at 0.66 was observed and constant. This peak was identified as 5-hydroxymethylfurfural, a degradation product of glucose. CONCLUSION: Norepinephrine diluted in G5% at 0.50mg/mL and 1.16mg/mL was physically and chemically stable over a period of 48hours at room temperature. These stability data of highly concentrated solutions provide additional knowledge to assist intensive care services in daily practice.
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Unidades de Cuidados Intensivos/estadística & datos numéricos , Norepinefrina/análisis , Vasoconstrictores/análisis , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Furaldehído/análogos & derivados , Furaldehído/análisis , Concentración de Iones de Hidrógeno , Luz , Norepinefrina/administración & dosificación , Polipropilenos , Reproducibilidad de los Resultados , Jeringas , Temperatura , Vasoconstrictores/administración & dosificaciónRESUMEN
French preparation guidelines state that pharmacy staff who manipulate cytotoxic drugs have to follow specific training. In order to assess the pharmaceutical assistants' skills and knowledge, we developed a "Cytotoxic Preparation Centralized Unit (CPCU) of errors," derived from the Canadian concept of "Chamber of horrors." A table listing 20 mistakes to track down was created and each pharmaceutical assistant spent 20 min in the "CPCU of errors" with the pharmacist, who wrote down the spotted mistakes in real time. Among the 21 trained pharmaceutical assistants, 15 were evaluated. On average, 11.9 mistakes on 20 were detected. The lowest score was 7 spotted errors on 20 and the highest was 16 on 20. Those results should be qualified depending on pharmaceutical assistants' years of experience in the preparation of chemotherapy. Those results may be explained by the way the role-playing was conducted. The simulation was not conducted during an actual preparation using the usual equipment. One of the major obstacles was the difficulty to clear some time for this project because its realization required a full-time pharmacist and the referring pharmaceutical assistant in addition to the evaluated pharmaceutical assistants. Overall, the staff feedback was positive and the role-playing led to a reminder of theoretical knowledge and the good use of some devices. It would be interesting to develop this type of project through a regional oncology network to create a medium that can be used by other hospitals.
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Antineoplásicos/uso terapéutico , Servicios Farmacéuticos , Farmacéuticos , Humanos , ConocimientoRESUMEN
A new function on the international database Stabilis® has been created: a database of research teams involved in stability and compatibility studies of drugs. The first part is descriptive. For each team, the list of publications and of molecules studied can be edited. A search function can extract data by using different criteria like the drug, galenic form, pharmacological class, molecule form (small molecule, monoclonal antibody), country, author and years of publications. The second part of the new function is interactive and allows Stabilis® users to suggest stability studies. After examination by collaborators of Stabilis®, the suggestions are rejected, modified or accepted, published on the website and available for all research teams. The United States of America (USA) was the main country in the 1990s but today, Europe has 67 active teams which publish stability studies and 50 for USA. Europe is now the more active zone in term of number of publications. Antibiotics and cytotoxics are the main pharmacological classes studied. Monoclonal antibodies are studied by few teams due to the complexity of the methodology to study the stability of these drugs. This database can facilitate the communication between research teams and users.
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Bases de Datos Factuales , Incompatibilidad de Medicamentos , Estabilidad de Medicamentos , Comunicación , Formas de Dosificación , Humanos , FarmaciaRESUMEN
Commercial infusion tubing and blood storage devices (tubing, blood and platelets bags) made of plasticized PVC were analyzed by spectroscopic, chromatographic and microscopic techniques in order to identify and quantify the additives added to the polymer (lubricants, thermal stabilizers, plasticizers) and to put into evidence their blooming onto the surface of the devices. For all the samples, deposits were observed on the surface but with different kinds of morphologies. Ethylene bis amide lubricant and metallic stearate stabilizers were implicated in the formation of these layers. In contact with aqueous media, these insoluble deposits were damaged, suggesting a possible particulate contamination of the infused solutions.
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Conservación de la Sangre/instrumentación , Cloruro de Polivinilo/química , Conservación de la Sangre/métodos , Humanos , Lubricantes/química , Estearatos/química , Propiedades de SuperficieRESUMEN
Pharmaceutical analyses of chemotherapy prescriptions by hospital pharmacists are activities codified by regulation and rules (bon usage). The involvement of the pharmacists in clinical pharmacy activities in the oncology setting is not clearly identified, justifying the development of a mapping of these activities from a questionnaire addressed to the professionals. One hundred and seven centers have participated to this study at the national level (overall participation rate of 32.4%). More than 95% of them used a computerized ordering system and three quarter of them submit the introduction of new compounds to an analysis by the drug therapeutic committee. Prescription analysis allowed detecting around 2% of errors from the current prescription. Clinical pharmacist participates to tumor boards of onco-hematology (RCP) at a level of 46% for senior pharmacist and 42% for junior pharmacist. This involvement in the RCP allowed anticipating protocol's modification and temporary used authorization. Ninety-two percent of the senior pharmacists estimate that they highlight the risk of no reimbursement for prescription out of the guideline during RCP, resulting to a modification of the prescription for 40% of them. This level of intervention is lower with respectively 64% and 10% for the juniors. This study underlines the expert value of the clinical pharmacist dedicated to oncology setting in pre and post analysis prescriptions. It could be targeted by a prospective analysis of both clinical and pharmacoeconomics impact of these interventions.
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Hematología , Oncología Médica , Farmacéuticos , Servicio de Farmacia en Hospital/organización & administración , Prescripciones de Medicamentos , Francia , Encuestas de Atención de la Salud , Humanos , Rol Profesional , Estudios ProspectivosRESUMEN
Nanoparticles made of metal-organic frameworks (nanoMOFs) attract a growing interest in gas storage, separation, catalysis, sensing and more recently, biomedicine. Achieving stable, versatile coatings on highly porous nanoMOFs without altering their ability to adsorb molecules of interest represents today a major challenge. Here we bring the proof of concept that the outer surface of porous nanoMOFs can be specifically functionalized in a rapid, biofriendly and non-covalent manner, leading to stable and versatile coatings. Cyclodextrin molecules bearing strong iron complexing groups (phosphates) were firmly anchored to the nanoMOFs' surface, within only a few minutes, simply by incubation with aqueous nanoMOF suspensions. The coating procedure did not affect the nanoMOF porosity, crystallinity, adsorption and release abilities. The stable cyclodextrin-based coating was further functionalized with: i) targeting moieties to increase the nanoMOF interaction with specific receptors and ii) poly(ethylene glycol) chains to escape the immune system. These results pave the way towards the design of surface-engineered nanoMOFs of interest for applications in the field of targeted drug delivery, catalysis, separation and sensing.
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Materiales Biocompatibles Revestidos/química , Ensayo de Materiales , Nanopartículas/química , Animales , Línea Celular , Ratones , PorosidadRESUMEN
The recommendations for the practical stability of anticancer drugs published in 2010 by the French Society of Hospital Pharmacists (SFPO) and the European Society of Oncology Pharmacists (ESOP) have been updated. Ten new molecules have been included (asparaginase, azacitidine, bevacizumab, clofarabine, eribuline mesylate, folinate sodium, levofolinate calcium, nelarabine, rituximab, temsirolimus).
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Antineoplásicos/química , Antineoplásicos/normas , Anticuerpos Monoclonales/análisis , Anticuerpos Monoclonales/química , Quimioterapia Adyuvante , Estabilidad de Medicamentos , Humanos , Oncología Médica , Farmacéuticos , Servicio de Farmacia en Hospital , Sociedades FarmacéuticasRESUMEN
We propose a concept of very specific immune-sensing platform dedicated to the quantification of biomarkers of Alzheimer disease (AD) in biological fluids. High sensitivity is required for the earliness of AD diagnostic, mainly based on clinical evaluation at present time. Accordingly, a controlled and adaptative surface functionalization of a silicon wafer with carboxylated alkyltrichlorosilane has been developed. The surface has extensively been characterized by AFM and X-ray Photoemissive Spectroscopy. The surface modification has been chemically assessed by XPS at each functionalization step. The survey spectra of silicon surface, after, 1, 3, 6 and 24 h of silanisation, highlight a significant enhancement of the functionalization efficiency upon time. The oxidation reaction has also been investigated by XPS and showed components related to the carboxylic group. AFM measurements pointed out a morphological modification consistent with a homogenous development of the carboxylic group and an almost protein monolayer on the surface. Moreover, we evaluated the biological activity of the grafted antibodies involved in (AD) biomarker detection onto this silanized surface by fluorescent microscopy. A sandwich immunoassay dedicated to the sensitive detection of one biomarker of Alzheimer disease (AD), the amyloid peptide 1-42 (Aß 1-42), was carried out. The results demonstrated that the controlled silanized surface provides a novel and viable way to detect biomarkers with high specificity and open the route to an original development of immune-sensing applications on such surfaces.
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Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/análisis , Técnicas Biosensibles/instrumentación , Inmunoensayo/instrumentación , Fragmentos de Péptidos/análisis , Biomarcadores/análisis , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Amiodarone hydrochloride, a class III antiarrhythmic agent, shows ß blocker-like and potassium channel blocker-like actions on the sinuatrial and atrioventricular nodes. It is given by mouth in the treatment of all forms of atrial, junctional and ventricular arrhythmias. Capsules for paediatric patients are not commercially available and must be prepared in the pharmacy department. The aim of the study was to evaluate the stability of amiodarone hydrochloride at different dosages, 10, 60 and 100 mg, in capsules for paediatric patients stored in three packages under dark conditions and at room temperatures over one year. At different intervals during the storage period, amiodarone hydrochloride concentration was tested using a high-performance liquid chromatography (HPLC) method. Amiodarone hydrochloride content remained greater than 95% of the initial concentration in all capsules at all dosages. The 10, 60 and 100 mg amiodarone paediatric capsules were stable for one year when stored in the three packages at ambient temperature and under dark conditions.
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Amiodarona/análisis , Antiarrítmicos/análisis , Cápsulas , Niño , Cromatografía Líquida de Alta Presión , Intervalos de Confianza , Oscuridad , Composición de Medicamentos , Embalaje de Medicamentos , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Humanos , Polvos , Reproducibilidad de los Resultados , TemperaturaRESUMEN
Stability studies performed by the pharmaceutical industry are only designed to fulfill licensing requirements. Thus, post-dilution or -reconstitution stability data are frequently limited to 24h only for bacteriological reasons regardless of the true chemical stability which could, in many cases, be longer. In practice, the pharmacy-based centralized preparation may require infusions to be made several days in advance to provide, for example, the filling of ambulatory devices for continuous infusions or batch preparations for dose banding. Furthermore, a non-justified limited stability for expensive products is obviously very costly. Thus, there is a compelling need for additional stability data covering practical uses of anticancer drugs. A European conference consensus was held in France, May 2010, under the auspices of the French Society of Oncology Pharmacy (SFPO) to propose adapted rules on stability in practical situations and guidelines to perform corresponding stability studies. For each anticancer drug, considering their therapeutic index, the pharmacokinetics/pharmacodynamics (PK/PD) variability, specific clinical use and risks related to degradation products, the classical limit of 10% of degradation can be inappropriate. Therefore, acceptance limits must be clinically relevant and should be defined for each drug individually. Design of stability studies has to reflect the different needs of the clinical practice (preparation for the week-ends, outpatient transportations, implantable devices, dose banding ). It is essential to use validated stability-indicating methods, separating degradation products being formed in the practical use of the drug. Sequential temperature designs should be encouraged to replicate problems seen in daily practice such as rupture of the cold-chain or temperature-cycling between refrigerated storage and ambient in-use conditions. Stressed conditions are recommended to evaluate not only the role of classical variables (pH, temperature, light) but also the mechanical stress. Physical stability such as particles' formation should be systematically evaluated. The consensus conference focused on the need to perform more studies on the stability of biotherapies, including a minimum of three complementary separating methods and a careful evaluation of submicron aggregates. The determination of the biological activity of proteins could be also useful. A guideline on the practical stability of anticancer drugs is proposed to cover current clinical and pharmaceutical practice. It should contribute to improved security of use, optimization of centralized handling and reduced costs. Finally, we have attempted to establish a new drug stability paradigm based on practical clinical needs, to complement regulatory guidelines which are essentially orientated to the stability of manufactured drugs.
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Antineoplásicos/química , Antineoplásicos/análisis , Industria Farmacéutica/normas , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Europa (Continente) , Francia , Luz , Reproducibilidad de los Resultados , Esterilización/normas , TemperaturaRESUMEN
The increasing use of array-comparative genomic hybridization (array-CGH) to identify copy number variations (CNVs) in patients with developmental delay (DD), mental retardation and/or dysmorphic features has allowed the recent recognition of numerous genomic imbalances, including the 15q13.3 microdeletion. Patients with this microdeletion generally present with relatively consistent breakpoints at BP4 and BP5, which include the CHRNA7 gene. About 100 index cases have been reported since the first publication in 2008. This large number of patients ascertained through highly variable samples has been necessary to describe the full phenotypic spectrum of this microdeletion, ranging from mental retardation with dysmorphic features, epilepsy, neuropsychiatric disturbances with or without cognitive impairment to complete absence of anomalies. Here, we describe a collaborative study reporting a new cohort of 12 index patients and 13 relatives carrying a heterozygous BP4-BP5 microdeletion out of a series of 4625 patients screened by array-CGH for DD. We confirm the clinical expressivity of the disease as well as the incomplete penetrance in seven families. We showed through a review of the literature that males are more likely to be symptomatic. Sequence analysis of CHRNA7 yielded no data to support the unmasking of recessive variants as a cause of phenotypic variability. We also report the first patient carrying a 15q13.3 homozygous microdeletion inherited from both parents. He had severe epileptic encephalopathy with retinopathy, autistic features and choreoathetosis. Besides the classical approximately 1.5 Mb BP4-BP5 microdeletion, we also describe three index patients and two relatives with a smaller 500 kb microdeletion, including the CHRNA7 gene.
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Deleción Cromosómica , Cromosomas Humanos Par 15/genética , Adolescente , Emparejamiento Base/genética , Niño , Preescolar , Hibridación Genómica Comparativa , Femenino , Heterocigoto , Humanos , Patrón de Herencia/genética , Masculino , Linaje , FenotipoRESUMEN
Cockayne syndrome is an autosomal recessive multisystem disorder characterized principally by neurological and sensory impairment, cachectic dwarfism, and photosensitivity. This rare disease is linked to mutations in the CSB/ERCC6 and CSA/ERCC8 genes encoding proteins involved in the transcription-coupled DNA repair pathway. The clinical spectrum of Cockayne syndrome encompasses a wide range of severity from severe prenatal forms to mild and late-onset presentations. We have reviewed the 45 published mutations in CSA and CSB to date and we report 43 new mutations in these genes together with the corresponding clinical data. Among the 84 reported kindreds, 52 (62%) have mutations in the CSB gene. Many types of mutations are scattered along the whole coding sequence of both genes, but clusters of missense mutations can be recognized and highlight the role of particular motifs in the proteins. Genotype-phenotype correlation hypotheses are considered with regard to these new molecular and clinical data. Additional cases of molecular prenatal diagnosis are reported and the strategy for prenatal testing is discussed. Two web-based locus-specific databases have been created to list all identified variants and to allow the inclusion of future reports (www.umd.be/CSA/ and www.umd.be/CSB/).
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Síndrome de Cockayne/genética , ADN Helicasas/genética , Enzimas Reparadoras del ADN/genética , Mutación/genética , Factores de Transcripción/genética , Secuencia de Aminoácidos , Síndrome de Cockayne/diagnóstico , ADN Helicasas/química , Enzimas Reparadoras del ADN/química , Bases de Datos Genéticas , Estudios de Asociación Genética , Humanos , Datos de Secuencia Molecular , Proteínas de Unión a Poli-ADP-Ribosa , Polimorfismo Genético , Alineación de Secuencia , Relación Estructura-Actividad , Factores de Transcripción/químicaRESUMEN
An unusual, intercalated photonic nanoarchitecture was discovered in the elytra of Taiwanese Trigonophorus rothschildi varians beetles. It consists of a multilayer structure intercalated with a random distribution of cylindrical holes normal to the plane of the multilayer. The nanoarchitectures were characterized structurally by scanning electron microscopy and optically by normal incidence, integrated and goniometric reflectance measurements. They exhibit an unsaturated specular and saturated non-specular component of the reflected light. Bioinspired, artificial nanoarchitectures of similar structure and with similar properties were realized by drilling holes of submicron size in a multilayer structure, showing that such photonic nanoarchitectures of biological origin may constitute valuable blueprints for artificial photonic materials.
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Escarabajos/química , Escarabajos/genética , Animales , Luz , Microscopía Electrónica de Rastreo , FotonesRESUMEN
Branchio-oculo-facial syndrome (BOFS) is an autosomal-dominant condition characterized by three main features, respectively: branchial defects, ocular anomalies, and craniofacial defects including cleft lip and/or palate (CL/P). We report on one family with three affected, and two sporadic cases that have been found to carry missense mutations in the newly reported BOFS gene: TFAP2A. This report confirms the involvement of this transcription factor in this developmental syndrome with clinical variability. Moreover, we present CT scan temporal bone anomalies in the familial cases, related to branchial arch defects, highlighting the importance of radiological investigations for differential diagnosis.
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Síndrome Branquio Oto Renal/genética , Hueso Temporal/anomalías , Factor de Transcripción AP-2/genética , Secuencia de Aminoácidos , Secuencia de Bases , Síndrome Branquio Oto Renal/complicaciones , Niño , Análisis Mutacional de ADN , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Linaje , Factor de Transcripción AP-2/fisiologíaRESUMEN
OBJECTIVE: To delineate a new syndrome of brain dysgenesis and cutis laxa based on the description of 11 patients belonging to nine unrelated families recruited through an international collaboration effort. METHODS: Careful clinical assessment of patients from birth to the age of 23 years with follow-up studies ranging from 3 to 20 years. Biochemical studies of serum proteins glycosylation by isoelectric focusing and capillary zone electrophoresis were performed in 10 patients. Brain MRI studies using conventional methods were analyzed in eight patients. RESULTS: An expanded clinical spectrum of a syndrome comprising facial dysmorphia (enlarged anterior fontanelles, downward slant of palpebral fissures, prominent root of the nose), a connective tissue disorder (inguinal hernia, hip dislocation, high myopia), and neurologic impairment was defined. Early developmental delay was followed by onset of generalized seizures by the end of the first decade and a subsequent neurodegenerative course. A defect of N- or N- plus O-glycosylation of serum transferrins and ApoCIII was observed in 10 patients. An unusual cobblestone-like cortical malformation over the frontal and parietal regions was seen in eight patients and cerebellar abnormalities, including two patients with Dandy-Walker malformation, were observed in three patients. CONCLUSIONS: Our results suggest that autosomal recessive cutis laxa, Debré type, initially considered a dermatologic syndrome, is a multisystemic disorder with cobblestone-like brain dysgenesis manifesting as developmental delay and an epileptic neurodegenerative syndrome. It might represent a metabolic cause of Dandy-Walker malformation. It is associated with a deficient N- and-O glycosylation of proteins and shares many similarities with muscle-eye-brain syndromes.
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Encéfalo/anomalías , Cutis Laxo , Síndrome de Dandy-Walker , Adolescente , Encéfalo/patología , Niño , Preescolar , Anomalías Congénitas/sangre , Anomalías Congénitas/genética , Anomalías Congénitas/patología , Cutis Laxo/sangre , Cutis Laxo/genética , Cutis Laxo/patología , Síndrome de Dandy-Walker/sangre , Síndrome de Dandy-Walker/genética , Síndrome de Dandy-Walker/patología , Electroforesis Capilar/métodos , Femenino , Glicosilación , Humanos , Lactante , Recién Nacido , Focalización Isoeléctrica/métodos , Estudios Longitudinales , Imagen por Resonancia Magnética/métodos , Masculino , Adulto JovenRESUMEN
Anodic decomposition of a vinylmagnesium halide or an ethynylmagnesium halide at a surface-hydrogenated silicon electrode leads to the formation of polymeric layers covalently anchored to the silicon surface. These layers have been characterized using spectroellipsometry and photoluminescence, infrared, and X-ray photoelectron spectroscopy. In the case of vinyl precursors, it appears that the multiple bonds are largely broken in the process. In the case of ethynyl, the layer formation rate is much higher for the chloride than for the bromide. The obtained polymer appears as a saturated skeleton bearing halide and unsaturated ethynyl groups. Furthermore, it appears that the solvent may be attacked by the ethynyl radicals leading to contamination of the polymer by solvent fragments, an effect that can largely be avoided by using appropriate solvents. The reaction pathways are discussed.
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We investigate optical excitations on single silver nanospheres and nanosphere composites with the Finite Difference Time Domain (FDTD) method. Our objective is to achieve polarization control of the enhanced local field, pertinent to SERS applications. We employ dimer and quadrumer structures, which can display broadband and highly confined near-field-intensity enhancement comparable to or exceeding the resonant value of smaller sized isolated spheres. Our results demonstrate that the polarization of the enhanced field can be controlled by the orientation of the multimers in respect to the illumination, rather than the illumination itself. In particular, we report cases where the enhanced field shares the same polarization with the exciting field, and cases where it is predominantly perpendicular to the source field. We call the later phenomenon depolarized enhancement. Furthermore, we study a realizable nanolens based on a tapered self-similar silver nanosphere array. The time evolution of the fields in such structures show conversion of a diffraction limited Gaussian beam to a focused spot, through sequential coupling of the nano-array spheres' Mie-plasmons. For a longitudinally excited nanolens design we observed the formation of an isolated focus with size about one tenth the vacuum wavelength. We believe such nanolens will aid scanning near-field optical microscopy (SNOM) detection and the excitation of surface plasmon based guiding devices.
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The aim of our study was to investigate the correlation between structural colour and scale morphology in butterflies. Detailed correlations between blue colour and structure were investigated in three lycaenid subfamilies, which represent a monophylum in the butterfly family Lycaenidae (Lepidoptera): the Coppers (Lycaeninae), the Hairstreaks (Theclinae) and the Blues (Polyommatinae). Complex investigations such as spectral measurements and characterization by means of light microscopy, scanning electron microscopy and transmission electron microscopy enabled us to demonstrate that: (i) a wide array of nanostructures generate blue colours; (ii) monophyletic groups use qualitatively similar structures; and (iii) the hue of the blue colour is characteristic for the microstructure and nanostructure of the body of the scales.
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Mariposas Diurnas/ultraestructura , Alas de Animales/ultraestructura , Animales , Mariposas Diurnas/clasificación , Color , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , NanoestructurasRESUMEN
Anodic decomposition of a phenylmagnesium halide at a surface-hydrogenated silicon electrode leads to formation of polymeric layers covalently anchored to the silicon surface. These layers have been characterized using spectroellipsometry, photoluminescence, infrared, and X-ray photoelectron spectroscopies. The phenyl ring appears preserved in the process, and the polymer formed is a polyphenylene. Contamination by aliphatic groups from the solvent may be minimized by using a solvent resistant to hydrogen abstraction by the phenyl radicals. Regioselectivity of the branching may be oriented to the para form by using 4-chlorophenylmagnesium bromide as the precursor.