Image texture analysis and gas sensor array studies applied to vanilla encapsulation by octenyl succinic anhydride starches

Native starch derivatization with octenyl succinic anhydride (OSA) is a chemical modification designed to enhance flavor microencapsulation performance. Hi Cap 100 and Capsul are two OSA starches derived from waxy maize base, which are especially suited for encapsulation processes. This work performs for the first time the encapsulation of vanilla extract with Capsul and Hi Cap 100 using both spray and freeze drying procedures. The encapsulation efficiency was studied correlating the starch texture with the aroma retention. Texture analysis was accomplished by means of grey level co-occurrence matrix feature extraction (GLCM), yielding image parameters that clearly differ in function of the type of starch and the drying method used for the encapsulation of the flavor. In parallel, the data recorded with a gas sensor array (e-nose) and analyzed by unsupervised multivariate methods allowed to follow up the evolution of the aroma through the whole process. The joint analysis of the GLCM and sensor array recorded data indicates that Capsul shows a higher capacity for vanilla encapsulation than Hi Cap 100. In addition, the obtained converging information from GLCM and e-nose data clearly indicates that particle texture and aroma encapsulation are connected.Fil: Rodríguez, Silvio David. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Wilderjans, Tom F.. Faculty of Psychology and Educational Sciences. Methodology of Educational Sciences Research Group; BélgicaFil: Sosa, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; ArgentinaFil: Bernik, Delia Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentin

In vitro assessment of skin irritation and corrosion properties of graphene-related materials on a 3D epidermis

The increasing use of graphene-related materials (GRMs) in many technological applications, ranging from electronics to biomedicine, needs a careful evaluation of their impact on human health. Skin contact can be considered one of the most relevant exposure routes to GRMs. Hence, this study is focused on two main adverse outcomes at the skin level, irritation and corrosion, assessed following two specific Test Guidelines (TGs) defined by the Organization for Economic Co-operation and Development (OECD) (439 and 431, respectively) that use an in vitro 3D reconstructed human epidermis (RhE) model. After the evaluation of their suitability to test a large panel of powdered GRMs, it was found that the latter were not irritants or corrosive. Only GRMs prepared with irritant surfactants, not sufficiently removed, reduced RhE viability at levels lower than those predicting skin irritation (≤50%, after 42 min exposure followed by 42 h recovery), but not at levels lower than those predicting corrosion (<50%, after 3 min exposure or <15% after 1 h exposure). As an additional readout, a hierarchical clustering analysis on a panel of inflammatory mediators (interleukins: IL-1α, IL-1β, IL-6, and IL-18; tumor necrosis factor-α and prostaglandin E2) released by RhE exposed to these materials supported the lack of irritant and pro-inflammatory properties. Overall, these results demonstrate that both TGs are useful in assessing GRMs for their irritant or corrosion potential, and that the tested materials did not cause these adverse effects at the skin level. Only GRMs prepared using toxic surfactants, not adequately removed, turned out to be skin irritants

In vivo anti-inflammatory activity of some naturally occurring O- and N-prenyl secondary metabolites.

A series of O- and N-prenyl secondary metabolites of insect, fungal, and plant origin have been evaluated for their topical anti-inflammatory activity using the Croton oil ear test in mice as a model of acute inflammation. Some of the tested compounds revealed an effect (ID50 = 0.31 +0.56 μmol/cm2) comparable with that of the reference non-steroidal anti-inflammatory drug indomethacin (ID50 = 0.23 μmol/cm2)

Effect of lead on proliferation, oxidative stress and genotoxic damage of 3T3-L1 fibroblasts

Lead (Pb) is an environmental and industrial contaminant that still represents a public health problem. In this paper, we investigated the effect of Pb on proliferation, lipid peroxidation and the number of micronucleated cells in exponentially growing 3T3-L1 fibroblasts, a cell line previously used to evaluate different environmental contaminants. We found that Pb (10 μM or higher) was able to inhibit proliferation of exponentially growing cells after 24-h treatment, which was evaluated by the MTT assay and cell counting in Neubauer chamber, but cell survival was not affected according to the trypan blue exclusion assay. On the other hand, Pb was able to increase lipid peroxidation and the number of micronucleated cells, which are indicative of oxidative stress and genotoxic damage respectively. We also found that removal of Pb after 24-h treatment allowed cells to recover proliferation. Our results indicate that Pb was able to induce oxidative stress and genotoxicity in this cell line under standardized conditions, which supports the involvement of Pb in similar effects observed in human exposed to this heavy metal. In addition, Pb inhibits proliferation of exponentially growing fibroblasts but cells resume proliferation after removal of this metal, which suggests that it is important to move away Pb-exposed individuals from the source of contamination.Fil: Martini, Claudia Noemí. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; ArgentinaFil: Sosa, Fernando Nicolás. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fuchs, Julio Silvio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Vila, María del Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentin

Assessment of skin sensitization properties of few-layer graphene and graphene oxide through the Local Lymph Node Assay (OECD TG 442B)

: Skin contact is one of the most common exposure routes to graphene-based materials (GBMs) during their small-scale and industrial production or their use in technological applications. Nevertheless, toxic effects in humans by cutaneous exposure to GBMs remain largely unexplored, despite skin contact to other related materials has been associated with adverse effects. Hence, this in vivo study was carried out to evaluate the cutaneous effects of two GBMs, focusing on skin sensitization as a possible adverse outcome. Skin sensitization by few-layer graphene (FLG) and graphene oxide (GO) was evaluated following the Organization for Economic Cooperation and Development (OECD) guideline 442B (Local Lymph Node Assay; LLNA) measuring the proliferation of auricular lymph node cells during the induction phase of skin sensitization. Groups of four female CBA/JN mice (8-12 weeks) were daily exposed to FLG or GO through the dorsal skin of each ear (0.4-40 mg/mL, equal to 0.01-1.00 mg/ear) for 3 consecutive days, and proliferation of auricular lymph node cells was evaluated 3 days after the last treatment. During this period, no clinical signs of toxicity and no alterations in body weight and food or water consumptions were observed. In addition, no ear erythema or edema were recorded as signs of irritation or inflammation. Bromo-deoxyuridine (BrdU) incorporation in proliferating lymphocytes from ear lymph nodes (stimulation indexes <1.6) and the histological analysis of ear tissues excluded sensitizing or irritant properties of these materials, while myeloperoxidase activity in ear biopsies confirmed no inflammatory cells infiltrate. On the whole, this study indicates the absence of sensitization and irritant potential of FLG and GO

Sepsis en una unidad de terapia intensiva polivalente: revisión de 2 años

Se analizaron retrospectivamente todas las historias clínicas de los pacientes ingresados al Servicio de Tera­pia Intensiva del Hospital Escuela desde enero de 2006 a diciembre de 2007, con el objetivo de evaluar inciden­ cia, factores de riesgo, foco infeccioso, fallos orgánicos, esquemas antibióticos y mortalidad relacionados a la sepsis. Ingresaron al estudio 531 pacientes, 156 tuvie­ron sepsis, de los cuales 108 pacientes (69,2%) tuvieron sepsis a la admisión y 48 pacientes (30,7%) desarrollaron el cuadro en UTI, con edad promedio de 45 años. Los focos infecciosos más frecuentes fueron pulmón (53,2%), abdomen (48%)y sistema nervioso central (SNC), (12,8%). En 51 pacientes (32,5%) se aislaron gérmenes Gram posi­tivos (32,5%), siendo el Staphylococco aureus oxacilino resistente (SAOR) y el neumococo los más frecuentes. Los Gram negativos se aislaron en 48 pacientes (29,3%), siendo los más frecuentes Pseudomona sp y Klebsiella sp. Los esquemas antibióticos empíricos más utilizados fueron vancomicina/ imipenem (27%) y ciprofloxacina/ clindamicina (16%). La antibióticoterapia dirigida más usada fue vancomicina/ imipenem (14,1%) y ceftriaxona/ metronidazol (13,4%). Los factores de riesgo asociados fueron injuria cerebral, edad mayor a 60 años, hipertensión arterial y diabetes. Los fallos orgánicos, fueron en orden de frecuencia: pulmonar, neurológico, cardiovascular, renal, hepático y hematológico. El SOFA (secuential organ failure assessments) promedio fue 6,78, el APACHE II (acute physiology and chronic health evaluation) prome­ dio fue 20, con una mortaliuad de 51%.

Occupational exposure to graphene based nanomaterials: Risk assessment

Graphene-based materials (GBMs) are a family of novel materials including graphene, few layer graphene (FLG), graphene oxide (GO), reduced graphene oxide (rGO) and graphene nanoplatelets (GNP). Currently, the risk posed by them to human health is associated mainly with the occupational exposure during their industrial and small-scale production or waste discharge. The most significant occupational exposure routes are inhalation, oral, cutaneous and ocular, inhalation being the majorly involved and most studied one. This manuscript presents a critical up-to-date review of the available in vivo toxicity data of the most significant GBMs, after using these exposure routes. The few in vivo inhalation toxicity studies (limited to 5-days of repeated exposure and only one to 5 days per week for 4 weeks) indicate inflammatory/fibrotic effects at the pulmonary level, not always reversible after 14/90 days. More limited in vivo data are available for the oral and ocular exposure routes, whereas the studies on cutaneous toxicity are at the initial stage. A long persistence of GBMs in rodents is recorded, while contradictory genotoxic data are reported. Data gap identification is also provided. Based on the available data, the occupational exposure limit cannot be determined. More experimental toxicity studies according to specific guidelines (tentatively validated for nanomaterials) and more information on the actual occupational exposure level to GBMs are needed. Furthermore, ADME (Absorption, Distribution, Metabolism, Excretion), genotoxicity, developmental and reproductive toxicity data related to the occupational exposure to GBMs have to be implemented. In addition, sub-chronic and/or chronic studies are still needed to completely exclude other toxic effects and/or carcinogenicity

Sanitary problems related to the presence of Ostreopsis spp. in the Mediterranean Sea: a multidisciplinary scientific approach

The increased presence of potentially toxic microalgae in the Mediterranean area is a matter of great concern. Since the end of the last century, microalgae of the genus Ostreopsis have been detected more and more frequently in the Italian coastal waters. The presence of Ostreopsis spp. has been accompanied by the presence of previously undetected marine biotoxins (palytoxins) into the ecosystem with the increased possibility of human exposure. In response to the urgent need for toxicity characterization of palytoxin and its congeners, an integrated study encompassing both in vitro and in vivo methods was performed

Brownian fluctuations and hydrodynamics of a microhelix near a solid wall

We combine two-photon lithography and optical tweezers to investigate the Brownian fluctuations and propeller characteristics of a microfabricated helix. From the analysis of mean squared displacements and time correlation functions we recover the components of the full mobility tensor. We find that Brownian motion displays correlations between angular and translational fluctuations from which we can directly measure the hydrodynamic coupling coefficient that is responsible for thrust generation. By varying the distance of the microhelices from a no-slip boundary we can systematically measure the effects of a nearby wall on the resistance matrix. Our results indicate that a rotated helix moves faster when a nearby no-slip boundary is present, providing a quantitative insight on thrust enhancement in confined geometries for both synthetic and biological microswimmers

ESTABLECIMIENTO IN VITRO DE EXPLANTES DE JUGLANS JAMAICENSIS C. DC. (Original)

The work was developed in the Plant Biotechnology Center of the University of Granma with the objective of evaluating the in vitro establishment of Juglansjamaicensis explants. To this end, nodal segments and leaves collected from an 8-year-old tree were used, located in the Germplasm Bank of the Study Center, as well as nuts collected from trees from the locality of California, municipality of Buey Arriba. Three experiments were established under a completely randomized design, for 20 explants (nodal segments, leaf explants and cotyledonary explants) for each treatment and two replications. 70% alcohol, sodium hypochlorite (NaClO), mercury bichloride (HgCl2) 0.1%, 2% CuSO4 as well as 1% Mancozeb were used as disinfectants. As a result, aseptic implantation of cotyledonary explants was achieved using NaClO (0.5%) and HgCl2 (0.1%), prior to a double disinfection of the nuts using NaClO, Mancozeb and HgCl2, and breaking them by pressure. with a manual metal press within the laminar flow, and therefore the most suitable material for the in vitro establishment of Juglansjamaicensis were the cotyledonary fragments. It also contributes to the in vitro multiplication of this species for the recovery of its populations, the reduction of its category of threat and the use of environmental goods and services.El trabajo se desarrolló en el Centro de Biotecnología de las plantas de la Universidad de Granma con el objetivo de evaluar el establecimiento in vitro de explantes de Juglansjamaicensis. Para ello se utilizaron segmentos nodales y hojas colectados de un árbol de 8 años de edad, ubicado en el Banco de germoplasma del Centro de Estudios, así como nueces recolectadas de árboles de la localidad de California, municipio de Buey Arriba. Se establecieron tres experimentos bajo un diseño completamente aleatorizado, para 20 explantes (segmentos nodales, explantes foliares y explantescotiledonares) por cada tratamiento y dos réplicas. Se usaron como desinfectantes alcohol al 70%, hipoclorito de sodio (NaClO), bicloruro de mercurio (HgCl2) 0,1%, CuSO4 al 2% así, como Mancozeb al 1%. Como resultados se logró la implantación aséptica de los explantescotiledonares utilizando NaClO (0,5%) y HgCl2 (0,1%), previo a una doble desinfección de las nueces con empleo de NaClO, Mancozeb y HgCl2, y su rompimiento mediante presión con una prensa metálica manual dentro del flujo laminar, y por lo tanto el material más adecuado para el establecimiento in vitro de Juglansjamaicensis fueron los fragmentos cotiledonares. Asimismo se contribuye a la multiplicación in vitro de esta especie para la recuperación de sus poblaciones, la reducción de su categoría de amenaza y el aprovechamiento de bienes y servicios ambientales