Influence of surfactant and processing conditions in the stability of oil-in-water nanoemulsions

This work evaluates the influence of the type of surfactant (Tween 20, SDS and DTAB) and processing conditions on the stability of oil-in-water nanoemulsions, measured in terms of hydrodynamic diameter (Hd), polydispersity index (PdI) and zeta potential (Zp). Nanoemulsions were prepared using high-pressure homogenization based on a 24 level factorial design. Results show that processing parameters such as homogenization pressure, surfactant concentrations and oil:water ratio significantly affected the values of Hd and PdI of nanoemulsions. The value of Hd of anionic nanoemulsions decreased (from 177 to 128 nm) with the increase of the homogenization pressure. The increase in the surfactant concentration and the decrease of the oil:water ratio lead to a decrease of Hd for the cationic nanoemulsions (from 198 to 135 nm). The increase of the oil:water ratio lead to a decrease of Hd for the non-ionic nanoemulsions (from 341 to 171 nm); this is contrary to the usual assumption that higher content in oil results in higher values of Hd. Those nanoemulsions showed a good kinetic stability (evaluated after centrifugation, heatingcooling cycles and thermal stress) upon measuring the Hd during 28 and 35 days of storage, without visual evidence of creaming and phase separation. After one year of storage the nanoemulsions produced with the anionic surfactant remained kinetically stable, without visual evidence of creaming and/or phase separation.Helder D. Silva, and Miguel A. Cerqueira (SFRH/BD/81288/2011, and SFRH/BPD/72753/2010, respectively) are the recipients of a fellowship from the Fundacao para a Ciencia e Tecnologia (FCT, Portugal). The authors would like to acknowledge to Francesco Donsi and Giovanna Ferrari from Department of Industrial Engineering, University of Salerno for helping in the viscosity and density measurements and to Rui Fernandes from IBMC, University of Porto for assistance in taking the TEM pictures. The authors thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013 and the project "BioInd-Biotechnology and Bioengineering for improved Industrial and Agro-Food processes", REF.NORTE-07-0124- FEDER-000028, co-funded by the Programa Operacional Regional do Norte (ON.2 - 0 Novo Norte), QREN, FEDER. We also thank to the European Commission: BIOCAPS (316265, FP7/REGPOT-2012-2013.1). The support of EU Cost Action FA1001 is gratefully acknowledged. Also the authors acknowledge Stepan for providing the Neobee 1053 oil

Nanoemulsions for food applications: development and characterization

The application of nanotechnology to food, medical and pharmaceutical industries has received great attention from the scientific community. Driven by the increasing consumers’ demand for healthier and safer food products and the need for edible systems able to encapsulate, protect, and release functional compounds, researchers are currently focusing their efforts in nanotechnology to address issues relevant to food and nutrition. Nanoemulsion technology is particularly suited for the fabrication of encapsulating systems for functional compounds as it prevents their degradation and improves their bioavailability. This review focuses on nanoemulsions and provides an overview of the production methods, materials used (solvents, emulsifiers and functional ingredients) and of the current analytical techniques that can be used for the identification and characterization of nanoemulsions. Finally, nanotechnological applications in foods currently marketed are reported.M.A. Cerqueira (SFRH/BPD/72753/2010) is recipient of a fellowship from the Fundacao para a Ciencia e Tecnologia (FCT, Portugal)

Erratum to Nanoemulsions for Food Applications: Development and Characterization (Food and Bioprocess Technology, (2012), 5, (854-867), 10.1007/s11947-011-0683-7)

Artigo completo publicado na revista "Food and Bioprocess Technology." 5:3 (2012) 854-867 e disponível no RepositóriUM em http://hdl.handle.net/1822/22397Where it reads: 2. Production of nanoemulsions 2.1. High-energy approaches • Ultrasound – when two immiscible liquids are submitted to high frequency sound waves in the presence of a surfactant, emulsion droplets are formed by cavitation. It should be read: 2. Production of nanoemulsions 2.2. High-energy approaches • Ultrasound – when two immiscible liquids are submitted to high intensity sound waves in the presence of a surfactant, emulsion droplets are formed by cavitation

Avaliação química e biológica da proteína do grão em cultivares de milho de alta qualidade protéica.

Cultivares de milho de alta qualidade protéica (QPM) desenvolvidos pela Embrapa Milho e Sorgo foram avaliados quanto ao conteúdo de aminoácidos essenciais e aproveitamento biológico da proteína, em ratos Wistar machos, recém-desmamados. Sete grupos de seis animais foram mantidos durante dez dias sob condições ambientais padronizadas, recebendo cada grupo uma das seguintes rações: a) controle a 10% e a 7% de proteína (caseína), b) aprotéica, c) experimentais com milho a 7% de proteína (QPM amarelo - BR 473, QPM branco - BR 451 e milho comum - BR 136), d) mistura arroz-feijão a 10% de proteína (1:1 em base protéica). A qualidade protéica do milho BR 473 foi semelhante à do milho BR 451 e significativamente superior (p<O,05) à do milho BR 136, segundo os índices NPR (Net Protein Ratio- 3,37; 3,54 e 2,58, respectivamente para BR 473, BR 451 e BR 136) e NPU (Net Protein Utilization - 56%,58% e 43%, respectivamente). Os milhos QPM possuem valor protéico elevado (média de 83% em relação à proteína de referência), similar ao da mistura arroz-feijão, constituindo-se em alimentos promissores para uso em programas de combate à desnutrição no Brasil, em especial para crianças de baixa renda

Microcrystalline silicon thin films prepared by RF reactive magnetron sputter deposition

Hydrogenated microcrystalline silicon (microc-Si:H) thin films with Cu as a dopant material (about 2 wt.%) were deposited by RF planar magnetron sputtering in an argon/hydrogen plasma. The composition and microstructure of the films were analysed by SEM, ERD/RBS, X-ray diffraction and Raman spectroscopy. These techniques revealed a columnar film structure, each column consisting of several small (nano) crystals with a lateral dimension up to 10nm. The crystals are oriented, generally with the (111) plane parallel to the sample surface. The hydrogen content of the thin films is about 27-33 at.%. Low deposition rates and low sputter gas pressures favour crystallisation and grain growth. The behaviour can be understood in terms of the diffusion or relaxation length of the deposited Si-atoms

Estudio retrospectivo de la eficacia y seguridad del natalizumab en el tratamiento de la esclerosis múltiple en Portugal

INTRODUCTION. Studies have shown that natalizumab is an effective treatment for relapsing-remitting multiple sclerosis (RRMS). To date, no data are available in Portuguese patients. AIM. To determine the efficacy and safety of natalizumab in patients with RRMS in routine clinical practice in Portugal. PATIENTS AND METHODS. Clinical data for adult patients with RRMS treated with natalizumab at specialist neurology centres in Portugal were entered retrospectively into a database for analysis between October 2010 and February 2012. Changes in annualized relapse rates (ARR), Expanded Disability Status Scale (EDSS) scores and disability status were analysed. RESULTS. A total of 383 patients from 20 centres were included. Prior to starting natalizumab, the baseline median EDSS score was 4 and the mean ARR was 1.64. Most patients had previously received multiple sclerosis treatment (93.0%). Median natalizumab treatment duration was 12 months. Natalizumab treatment was associated with significant (p = 12 months (n = 288) and for >= 24 months (n = 160). Natalizumab was more effective in patients with less disability (EDSS < 3) and in those who had not previously received disease-modifying treatments. Two cases of progressive multifocal leukoencephalopathy were reported. No new unexpected adverse events occurred. CONCLUSION. Natalizumab is well tolerated, and is effective in reducing relapse rate and stabilising disease in patients with RRMS in the clinical practice setting in Portugal. Its efficacy persists with continued treatment, and it may be particularly effective in patients with less disability and without prior disease modifying therapy.Introduccion. Los estudios han demostrado que el natalizumab constituye un tratamiento eficaz contra la esclerosis multiple remitente recurrente (EMRR). Hasta la fecha, no habia datos de pacientes portugueses. Objetivo. Determinar la eficacia y la seguridad del natalizumab en pacientes con EMRR atendidos en la practica clinica ordinaria en Portugal. Pacientes y metodos. Los datos clinicos de adultos con EMRR tratados con natalizumab en centros especializados de neurologia en Portugal se introdujeron de forma retrospectiva en una base de datos para llevar a cabo un analisis entre octubre de 2010 y febrero de 2012. Se analizo el cambio en la tasa anualizada de brotes (TAB), en las puntuaciones de la escala ampliada de discapacidad (EDSS) y en el estado de discapacidad. Resultados. Se admitio un total de 383 pacientes atendidos en 20 centros. Antes de iniciar el tratamiento con natalizumab, la mediana inicial de la EDSS era de 4,0 y la TAB media, de 1,64. La mayor parte de los pacientes ya habia recibido tratamiento contra la esclerosis multiple (93,0%). La duracion media del tratamiento con natalizumab era de 12 meses. El tratamiento propicio reducciones significativas (p = 12 meses (n = 288) y durante >= 24 meses (n = 160). El natalizumab resulto mas eficaz en los pacientes que presentaban un menor grado de discapacidad (EDSS < 3,0) y en los que no habian recibido ningun tratamiento modificador de la enfermedad. Se notificaron dos casos de leucoencefalopatia multifocal progresiva. No hubo efectos adversos inesperados. Conclusion. El natalizumab presenta una tolerabilidad satisfactoria y se muestra eficaz en la reduccion de las recidivas y la estabilizacion de la EMRR en el marco de la practica clinica ordinaria en Portugal. Conserva su eficacia con el tratamiento continuado y podria ser eficaz especialmente en los pacientes con menos discapacidad y en aquellos que no han recibido ningun tratamiento modificador de la enfermedad hasta el momento

Central Diabetes Insipidus Following Immunization With BNT162b2 mRNA COVID-19 Vaccine: a Case Report

Introduction: Cases of central diabetes insipidus (CDI) have been reported after COVID-19 infection, with hypophysitis being the most likely cause. COVID-19 vaccines potential adverse effects may mimetize some of these complications. Case report: Woman 37 years old, with rheumatoid arthritis under adalimumab (40 mg twice a month) since December 2018. She was in her usual state of health when she has received the second dose of BNT162b2 mRNA COVID-19 vaccine (June 2021). Seven days later, she started reporting intense thirst and polyuria and consulted her family physician. Blood analysis: creatinine 0.7 mg/dL, glucose 95mg/dL, Na+ 141mEq/L, K+ 3.9 mEq/L, TSH 3.8 mcUI/L (0.38-5.33), FT4 0.9 ng/dL (0.6-1.1), cortisol 215.4 nmol/L (185-624), ACTH 21.9 pg/mL (6- 48), FSH 4.76 UI/L, LH5.62 UI/L, estradiol 323 pmol/L, IGF1 74.8 ng/mL (88-209), PRL 24.7mcg/L (3.3-26.7) osmolality 298.2 mOs/Kg (250- 325); Urine analysis: volume 10200 mL/24h, osmolality 75 mOs/Kg (300-900), density 1.002. On water restriction test: 0' - Serum osmolality 308.8mOsm/Kg vs. urine osmolality 61.0 mOsm/Kg; 60' - urine osmolality 102 mOsm/Kg; urine osmolality 1 h after desmopressine was 511mOsm/kg. MRI revealed no abnormal signs consistent with hypophysitis except for the loss of the posterior pituitary bright spot on T1 weighted imaging. Diagnosis of CDI was assumed, and started therapy with desmopressine. A report of potential adverse effect was addressed to national health authorities. Conclusion: In hypophysitis MRI often shows loss of posterior pituitary bright spot on T1 weighted imaging, pituitary enlargement or stalk thickening but those findings were not present in this patient. To the best of our knowledge, CDI has never been reported following administration of a COVID-19 vaccine.info:eu-repo/semantics/publishedVersio

Management of Operational Parameters and Novel Spinneret Configurations for the Electrohydrodynamic Processing of Functional Polymers

[EN] Functional materials have become key drivers in the development of multiple high-end technologies. Electrohydrodynamic processing (EHDP) is a straightforward method to generate polymer micro- and nanostructures that can be applied to the food, pharmaceutical, environmental, and biomedical areas, among others, since these can yield materials with higher performance. Some of the EHDP's advantages over other polymer processing technologies rely on its high versatility, by which the final assembly can be modified in different ways to combine materials with multiple properties and also in different morphological structures, and the use of room processing conditions, meaning that thermolabile ingredients can be incorporated with minimal activity loss. This review provides the historical background, process basics, and the state-of-the-art of the most recent advances achieved in the EHDP technology dealing with the control of its operational parameters to optimize processability and achieve end-product quality and homogeneity. It also focuses on the newly developed modes of operation and spinneret configurations that can lead to the formation of a wide range of micro- and nanostructures with different functionalities and solve some of its current technical limitations. Finally, it also further highlights the potential applications of the resultant hierarchical functional polymer-based materials obtained by these novel EHDP methods.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and by the I&D&I AgriFood XXI project, operation number NORTE-01-0145-FEDER-000041, co-financed by the European Regional Development Fund (FEDER) under the scope of NORTE 2020 (ProgramaOperacional Regional do Norte 2014/2020). Pedro Silva is the recipient of a fellowship (SFRD/BD/130247/2017) supported by FCT. S. TorresGiner acknowledges Spanish Ministry of Science and Innovation (MICI) for the funding received during his Ramon y Cajal contract (RYC2019027784-I).Silva, PM.; Torres-Giner, S.; Vicente, AA.; Cerqueira, MA. (2022). Management of Operational Parameters and Novel Spinneret Configurations for the Electrohydrodynamic Processing of Functional Polymers. Macromolecular Materials and Engineering. 307(5):1-21. https://doi.org/10.1002/mame.202100858121307

Estudo preliminar da actividade antimicrobiana das folhas de cydonia oblonga miller

O marmelo é reconhecido como uma importante fonte de compostos promotores da saúde sendo que a actividade antimicrobiana dos extractos da sua polpa, casca e sementes foi já avaliada. Não existem porém estudos da actividade antimicrobiana das folhas de marmeleiro. Este estudo preliminar teve como objectivo determinar a actividade dos seus extractos metanólicos. Concluiu-se que os extractos testados não apresentam actividade em E. coli, S. aureus, C. albicans, C. glabrata, A. niger, A. fumigatus, Mucor spp e Absídia spp pelo que novos extractos devem ser preparados sendo posteriormente avaliados. Quince fruit is recognized an important source of health promoting compounds being the antimicrobial activities of the quince pulp, peel grape and seed extracts already evaluated. No results are known for quince leaves antimicrobial activity. This preliminary work intended to determine the activity of quince leaves methanolic extracts. These had no antimicrobial activity either against E. coli, S. aureus, C. albicans, C. glabrata, A. niger, A. fumigatus, Mucor spp e Absídia spp and new extracts must be prepared and evaluated