Aplicação e avanços da espectroscopia de luminescência em análises farmacêuticas

This paper provides a review on the latest advances and applications of the luminescence spectroscopy for the development of pharmaceuticals analyses methods, basically based on the photo- and chemiluminescence. The different forms of the drugs determination on pharmaceuticals through the fluorescence and chemiluminescence are discussed. The analyses include the drugs native fluorescence (liquid and solid-phases); the fluorescence from the oxidizing or reducing forms of the drug; the fluorescence from the chemical derivatization and their photochemistry and hydrolysis reactions. The quenching of luminescence and chemiluminescence generation for the pharmaceutical quantification are also shown. Finally, the trends and future perspectives of the luminescence spectroscopy in the field of the pharmaceutical research are discussed.

Beauty and personal care in mass market: A strategic analysis of perfumery and cosmetics at Sonae MC

Directed internship

Entry strategies on an emerging market: Brazil: case studies of French cosmetics companies in Brazil

Este trabalho envolve as estrategias de entrada sobre um mercado emergente, o mercado brasileiro. Os estudos de casos que apoiam o assunto são de empresas francesas do setor de cosméticos. Uma revisão da literatura sobre o assunto sera comparada com os resultados dos estudos de caso. Isso para conduzir numa observação do estado atual das caractéristicos de instalação no mercado brasileiro deste setor para empresas estrangeiras de tamanho médio. O estudo da literatura que já existe sobre o assunto se concentra sobre varias problemáticas conectadas com a problemática geral: as razões para internacionalizar, o modo de entrada, os obstáculos encontrados, as estrategias especificais e as adaptações do marketing mix. Depois este trabalho se concentra sobre tres empresas francesas representativas das problematicas atuais do setor : Norlessi, LaboBio e Plains Cosmetics. Os estudos de caso são sustentados por entrevistas e coleção de dados de varios origens, descrevedo mas precisamente na parte de methodologia. Depois será feito uma cross-analysis tentando comparar as conclusões do estudo empirico e do estudo literário. As conclusões finais tem como objetivo de ser uma observação objetiva do raciocinio das empresas consideradas sobre as problemáticas escolhidas.

Application of an HPLC method for analysis of propolis extract

Propolis obtained from honeybee hives has been widely used in medicine, cosmetics, and industry due to its versatile biological activities (antioxidant, antimicrobial, fungicidal, antiviral, antiulcer, immunostimulating, and cytostatic). These activities are mainly attributed to the presence of flavonoids in propolis, which points out the interest in quantifying these constituents in propolis preparations, as well as validation of analytical methodologies. High-performance liquid chromatography (HPLC) methods have been reported to quantify isolated flavonoids or these compounds in complex biological matrices, such as herbal raw materials and extractive preparations. An efficient, precise, and reliable method was developed for quantification of propolis extractive solution using HPLC with UV detection. The chromatograms were obtained from various gradient elution systems (GES) tested in order to establish the ideal conditions for the analysis of propolis extractive solution, using methanol and water: acetonitrile (97.5 : 2.5, v/v) as mobile phase. Gradient reversed phase chromatography was performed using a stainless steel column (250 x 4.6 mm i.d., 5 mum) filled with Chromsep RP 18 (Varian), column temperature at 30.0 +/- 0.1degreesC and detection at 310 nm. The main validation parameters of the method were also determined. The method showed linearity for chrysin in the range 0.24-2.4 mug mL(-1) with good correlation coefficients (0.9975). Precision and accuracy were determined. The obtained results demonstrate the efficiency of the proposed method. The analytical procedure is reliable and offers advantages in terms of speed and cost of reagents.

Analysis of zinc oxide nanoparticles as a potential mutagen of respiratory epithelia

Metallische Nanopartikel und ihre Oxide (z.B. ZnO NP, TiO2 NP und Fe2O3 NP) werden aufgrund ihrer chemischen und physikalischen Eigenschaften häufig als Additive in der Reifenproduktion, in Katalysatoren, Lebensmitteln, Arzneimitteln und Kosmetikprodukten verwendet. Künftig wird ein kontinuierlicher Anstieg der industriellen Anwendung (~ 1663 Tonnen im Jahr 2025) mit gesteigerter Freisetzung in die Umwelt erwartet, was zwangsläufig zu einer vermehrten Aufnahme über das respiratorische Epithel führt. Metalldampffieber ist als gesundheitsschädigender Effekt von Metalloxid-haltigen Aerosolen (z.B. ZnO) nach Inhalation bekannt. Immunreaktionen, wie beispielsweise Entzündungen, werden häufig mit der Entstehung von Sauerstoffradikalen (ROS) in Verbindung gebracht, die wiederum zu DNA-Schäden führen können. Drei mögliche Ursachen der Genotoxität werden angenommen: direkte Interaktion von Nanopartikeln mit intrazellulären Strukturen, Interaktion von Ionen dissoziierter Partikel mit intrazellulären Strukturen sowie die Entstehung von ROS initiiert durch Partikel oder Ionen.rnDie vorliegende Studie befasst sich mit den Mechanismen der Genotoxizität von ZnO Nanopartikeln (ZnO NP), als Beispiel für metallische Nanopartikel, im respiratorischen Epithel. In der Studie wurde gezielt die intrazelluläre Aufnahme und Verteilung von ZnO NP, deren Toxizität, deren DNA schädigendes Potential sowie die Aktivierung der DNA damage response (DDR) analysiert.rnEs konnten kaum internalisierte ZnO NP mittels TEM detektiert werden. Innerhalb der ersten Sekunden nach Behandlung mit ZnO NP wurde spektrofluorometrisch ein starker Anstieg der intrazellulären Zn2+ Konzentration gemessen. In unbehandelten Zellen war Zn2+ in granulären Strukturen lokalisiert. Die Behandlung mit ZnO NP führte zu einer Akkumulation von Zn2+ in diesen Strukturen. Im zeitlichen Verlauf verlagerten sich die Zn2+-Ionen in das Zytoplasma, sowie in Zellkerne und Mitochondrien. Es wurde keine Kolokalisation von Zn2+ mit den frühen Endosomen und dem endoplasmatischen Retikulum beobachtet. Die Vorbehandlung der Zellen mit Diethylen-triaminpentaessigsäure (DTPA), als extrazellulärem Komplexbildner, verhinderte den intrazellulären Anstieg von Zn2+ nach Behandlung mit den Partikeln.rnDie Behandlung mit ZnO NP resultierte in einer zeit- und dosisabhängigen Reduktion der zellulären Viabilität, während die intrazelluläre ROS-Konzentrationen in den ersten 30 min leicht und anschließend kontinuierlich bis zum Ende der Messung anstiegen. Außerdem verringerte sich das mitochondriale Membranpotential, während sich die Anzahl der frühapoptotischen Zellen in einer zeitabhängigen Weise erhöhte. rnDNA Doppelstrangbrüche (DNA DSB) wurden mittels Immunfluoreszenz-Färbung der γH2A.X foci sichtbar gemacht und konnten nach Behandlung mit ZnO NP detektiert werden. Die Vorbehandlung mit dem Radikalfänger N-Acetyl-L-Cytein (NAC) resultierte in stark reduzierten intrazellulären ROS-Konzentrationen sowie wenigen DNA DSB. Die DNA Schädigung wurde durch Vorbehandlung mit DTPA ganz verhindert.rnDie Aktivierung der DDR wurde durch die Analyse von ATM, ATR, Chk1, Chk2, p53 und p21 mittels Western Blot und ELISA nach Behandlung mit ZnO NP überprüft. Der ATR/Chk1 Signalweg wurde durch ZnO NP nicht aktiviert. Die Komplexierung von Zn2+ resultierte in einer verminderten ATM/Chk2 Signalwegaktivierung. Es zeigte sich, dass das Abfangen von ROS keinen Effekt auf die ATM/Chk2 Signalwegaktivierung hatte.rnZusammengefasst wurde festgestellt, dass die Exposition mit ZnO NP in der Entstehung von ROS, reduzierter Viabilität und vermindertem mitochondrialem Membranpotential resultiert, sowie zeitabhängig eine frühe Apoptose initiiert. ZnO NP dissoziierten extrazellulär und wurden schnell als Zn2+ über unbekannte Mechanismen internalisiert. Die Zn2+-Ionen wurden im Zytoplasma, sowie besonders in den Mitochondrien und dem Zellkern, akkumuliert. Die DDR Signalgebung wurde durch ZnO NP aktiviert, jedoch nicht durch NAC inhibiert. Es wurde gezeigt, dass DTPA die DDR Aktivierung komplett inhibierte. Die Behandlung mit ZnO NP induzierte DNA DSB. Die Inhibition von ROS reduzierte die DNA DSB und die Komplexierung der Zn2+ verhinderte die Entstehung von DNA DSB.rnDiese Daten sprechen für die Dissoziation der Partikel und die hierbei freigesetzten Zn2+ als Hauptmediator der Genotoxizität metallischer Nanopartikel. rn

Laparoscopic versus open total mesorectal excision for stage I-III mid and low rectal cancer: a retrospective 5 years analysis

Introduction. Total mesorectal excision (TME) is the cornerstone of a correct surgical therapy for extraperitoneal rectal cancer. Aim of the study is to evaluate our 5 years experience confronting retrospectively laparoscopic (lap) TME in respect to its laparotomic (open) counterpart. Patients and Methods. 30 patients were treated laparoscopically for stage I-III extraperitoneal rectal cancer and retrospectively compared to a homogeneous group, stratified for sex, age, comorbidities and stage of disease. Results. 30 days mortality was zero for both groups, while morbidity was 20% for the lap group and 36.6% for the open group. Mean lymph nodes harvested was 24 ± 12 for the lap group, 26 ± 14 for the open group (p > 0.05). Five years overall and disease free survival was respectively 82.2% and 81.4% in the lap group, 79.9% and 79.6% in the open group, without statistical significance (p>0.05). Discussion. Minimally invasive TME resulted a safe, effective and oncologically adequate procedure when retrospectively compared to its laparotomic counterpart, with 5 years overall survival and disease free survival reaching no statistical significance compared to the open approach, but with all the advantages of the laparoscopy such as less pain and blood loss, faster recovery, less morbidity and better cosmetics. Conclusions. Our study has retrospectively demonstrated that laparoscopic TME is feasible and oncologically effective, even if it remains a complex minimally invasive procedure, requiring adequate skill. More prospective, randomized studies are necessary to define such a procedure as the new gold standard in treatment of stage I-III extraperitoneal rectal cancer.

Analysis of N-nitrosames in water using micellar electrokinetic chromatography (MEKC) and development of online and offline methods of extraction and enrichment of neutral polar analytes

Evaluation of the quality of the environment is essential for human wellness as pollutants in trace amounts can cause serious health problem. Nitrosamines are a group of compounds that are considered potential carcinogens and can be found in drinking water (as disinfection byproducts), foods, beverages and cosmetics. To monitor the level of these compounds to minimize daily intakes, fast and reliable analytical techniques are required. As these compounds are relatively highly polar, extraction and enrichment from environmental samples (aqueous) are challenging. Also, the trend of analytical techniques toward the reduction of sample size and minimization of organic solvent use demands new methods of analysis. In light of fulfilling these requirements, a new method of online preconcentration tailored to an electrokinetic chromatography is introduced. In this method, electroosmotic flow (EOF) was suppressed to increase the interaction time between analyte and micellar phase, therefore the only force to mobilize the neutral analytes is the interaction of analyte with moving micelles. In absence of EOF, polarity of applied potential was switched (negative or positive) to force (anionic or cationic) micelles to move toward the detector. To avoid the excessive band broadening due to longer analysis time caused by slow moving micelles, auxiliary pressure was introduced to boost the micelle movement toward the detector using an in house designed and built apparatus. Applying the external auxiliary pressure significantly reduced the analysis times without compromising separation efficiency. Parameters, such as type of surfactants, composition of background electrolyte (BGE), type of capillary, matrix effect, organic modifiers, etc., were evaluated in optimization of the method. The enrichment factors for targeted analytes were impressive, particularly; cationic surfactants were shown to be suitable for analysis of nitrosamines due to their ability to act as hydrogen bond donors. Ammonium perfluorooctanoate (APFO) also showed remarkable results in term of peak shapes and number of theoretical plates. It was shown that the separation results were best when a high conductivity sample was paired with a BGE of lower conductivity. Using higher surfactant concentrations (up to 200 mM SDS) than usual (50 mM SDS) for micellar electrokinetic chromatography (MEKC) improved the sweeping. A new method for micro-extraction and enrichment of highly polar neutral analytes (N-Nitrosamines in particular) based on three-phase drop micro-extraction was introduced and its performance studied. In this method, a new device using some easy-to-find components was fabricated and its operation and application demonstrated. Compared to conventional extraction methods (liquid-liquid extraction), consumption of organic solvents and operation times were significantly lower.

Raman microscopy of formamide-intercalated kaolinites treated by controlled-rate thermal analysis technology

Raman spectroscopy of formamide-intercalated kaolinites treated using controlled-rate thermal analysis technology (CRTA), allowing the separation of adsorbed formamide from intercalated formamide in formamide-intercalated kaolinites, is reported. The Raman spectra of the CRTA-treated formamide-intercalated kaolinites are significantly different from those of the intercalated kaolinites, which display a combination of both intercalated and adsorbed formamide. An intense band is observed at 3629 cm-1, attributed to the inner surface hydroxyls hydrogen bonded to the formamide. Broad bands are observed at 3600 and 3639 cm-1, assigned to the inner surface hydroxyls, which are hydrogen bonded to the adsorbed water molecules. The hydroxyl-stretching band of the inner hydroxyl is observed at 3621 cm-1 in the Raman spectra of the CRTA-treated formamide-intercalated kaolinites. The results of thermal analysis show that the amount of intercalated formamide between the kaolinite layers is independent of the presence of water. Significant differences are observed in the CO stretching region between the adsorbed and intercalated formamide.

Detailed analysis of a conservative difference approximation for the time fractional diffusion equation

Diffusion equations that use time fractional derivatives are attractive because they describe a wealth of problems involving non-Markovian Random walks. The time fractional diffusion equation (TFDE) is obtained from the standard diffusion equation by replacing the first-order time derivative with a fractional derivative of order α ∈ (0, 1). Developing numerical methods for solving fractional partial differential equations is a new research field and the theoretical analysis of the numerical methods associated with them is not fully developed. In this paper an explicit conservative difference approximation (ECDA) for TFDE is proposed. We give a detailed analysis for this ECDA and generate discrete models of random walk suitable for simulating random variables whose spatial probability density evolves in time according to this fractional diffusion equation. The stability and convergence of the ECDA for TFDE in a bounded domain are discussed. Finally, some numerical examples are presented to show the application of the present technique.

Determination of preventive maintenance lead time using hybrid analysis

The time for conducting Preventive Maintenance (PM) on an asset is often determined using a predefined alarm limit based on trends of a hazard function. In this paper, the authors propose using both hazard and reliability functions to improve the accuracy of the prediction particularly when the failure characteristic of the asset whole life is modelled using different failure distributions for the different stages of the life of the asset. The proposed method is validated using simulations and case studies.