Effect of neoadjuvant chemotherapy on low-density lipoprotein (LDL) receptor and LDL receptor-related protein 1 (LRP-1) receptor in locally advanced breast cancer

Low-density lipoprotein (LDL) receptors are overexpressed in most neoplastic cell lines and provide a mechanism for the internalization and concentration of drug-laden nanoemulsions that bind to these receptors. The aim of the present study was to determine whether the administration of standard chemotherapeutic schemes can alter the expression of LDL and LDL receptor-related protein 1 (LRP-1) receptors in breast carcinoma. Fragments of tumoral and normal breast tissue from 16 consecutive volunteer women with breast cancer in stage II or III were obtained from biopsies before the beginning of neoadjuvant chemotherapy and after chemotherapy, from fragments excised during mastectomy. Tissues were analyzed by immunohistochemistry for both receptors. Because complete response to treatment was achieved in 4 patients, only the tumors from 12 were analyzed. Before chemotherapy, there was overexpression of LDL receptor in the tumoral tissue compared to normal breast tissue in 8 of these patients. LRP-1 receptor overexpression was observed in tumors of 4 patients. After chemotherapy, expression of both receptors decreased in the tumors of 6 patients, increased in 4 and was unchanged in 2. Nonetheless, even when chemotherapy reduced receptors expression, the expression was still above normal. The fact that chemotherapy does not impair LDL receptors expression supports the use of drug carrier systems that target neoplastic cells by the LDL receptor endocytic pathway in patients on conventional chemotherapy.

Production and characterization of lipid microparticles produced by spray cooling encapsulating a low molar mass hydrophilic compound

The objective of this research was to produce and characterize lipid particles (MpLs) that may be used as carriers of high amounts of hydrophilic core and evaluate the influence of the core amount on the performance of lipid microparticles. The MpLs were produced by spray cooling from solid and liquid lipid mixtures (stearic and oleic fatty acids and partly hydrogenated vegetable fat) containing glucose solution as core and soy lecithin as surfactant. The performance of MpLs was evaluated by means of the effective amount of encapsulated core, the core amount present on the surface of MpLs (superficial glucose) and the core release profile in aqueous solution. Morphological observations showed that MpLs presented spherical shape and a rugged and continuous surface, and an average diameter between 25 and 32 µm. The effective amount of encapsulated core was greater than 78% for all formulations evaluated. Larger amounts of superficial glucose were found in formulations in which more concentrated glucose solutions were used, regardless of the glucose lipid-solution ratio. The release results showed that core retention was significantly influenced by the glucose solution concentration, whereas release modulation was influenced by the glucose lipid-solution ratio.

The use of cashew apple residue as source of fiber in low fat hamburgers

The main purpose of this study was to produce hamburgers with partial substitution of the meat with cashew apple residue powder. The powder residue was obtained after the extraction of the pulp and dehydration in stove with air circulation. Three formulations of hamburgers with increasing concentration of the residue as well as a control sample were prepared. The formulated products with cashew apple residue powder presented lower humidity and proteins and 35% lipid reduction. However, there was an increase in carbohydrates and pH with the addition of the powder from the cashew apple residue. Some formulations showed an improvement of the final product yield. The total dietary fiber value was between 0 and 7.66%, with higher content of insoluble dietary fiber. The addition of up to 10.70% of the residue did not cause significant sensory changes in the flavor of the samples. The production of hamburgers with a partial substitution of cow meat with the cashew apple residue could be a feasible option since it resulted in product with high nutritional quality that is rich or have high dietary fiber content and is low in fat.

Effect of thinning on flower and fruit and of edible coatings on postharvest quality of jaboticaba fruit stored at low temperature

Jaboticaba is a Brazilian fruit, native to the Atlantic forest, which belongs to the Myrtaceae family. In this work we describe the effect of the thinning of "flower", "fruit" and "flower & fruit" compared to non-thinned fruit (control) and of edible coatings with respect on nutritional composition, overall acceptability and shelf-life of jaboticaba ‘Sabara’, grown in an irrigated commercial orchard. "Flower and fruit" thinning allows fruit with higher quality as diameter, volume and mass. Non-thinned fruit shows higher yield, however fruit have lower quality. As a result of the improving quality at harvest, the shelf life was twice (~8 days) for thinned fruit. The lack of change in concentration of soluble sugar and absence of formation of volatile compounds during storage indicate that there was no natural fermentation of the jaboticaba pulp after harvest. Treatments with wax and calcium did not improve the jaboticaba shelf life.

Mesure de la concentration en métaux traces dans la solution de sol par microlysimétrie

La présente étude porte sur l’évaluation d’une méthode d’acquisition de la solution de sol présente à l’interface sol-racine, dans la rhizosphère. Cette interface constitue le lieu privilégié de prise en charge par les plantes des contaminants, tels que les métaux traces. Comme les plantes acquièrent ces éléments à partir de la phase liquide, la solution de sol de la rhizosphère est une composante clé pour déterminer la fraction de métaux traces biodisponibles. La microlysimétrie est la méthode in situ la plus appropriée pour aborder les difficultés liées à l’échelle microscopique de la rhizosphère. Ainsi, dans les études sur la biodisponibilité des métaux traces au niveau de la rhizosphère, les microlysimètres (Rhizon©) gagnent en popularité sans, toutefois, avoir fait l’objet d’études exhaustives. L’objectif de cette étude est donc d’évaluer la capacité de ces microlysimètres à préserver l’intégrité chimique de la solution, tout en optimisant leur utilisation. Pour ce faire, les microlysimètres ont été soumis à une série d’expériences en présence de solutions et de sols, où la quantité de solution prélevée et le comportement des métaux traces (Cd, Cu, Ni, Pb, Zn) ont été étudiés. Les résultats montrent que les microlysimètres fonctionnent de façon optimale lorsque le contenu en eau du sol est au-dessus de la capacité au champ et lorsqu’il y a peu de matière organique et d’argile. Les sols sableux ayant un faible contenu en C organique reproduisent mieux le volume prélevé et la solution sous la capacité au champ peut être récoltée. L’utilisation des microlysimètres dans ces sols est donc optimale. Dans les essais en solution, les microlysimètres ont atteint un équilibre avec la solution après 10 h de prélèvement. En respectant ce délai et les conditions optimales préalablement établies (pH acide et COD élevé), les microlysimètres préservent la composition chimique de la solution. Dans les essais en sol, cet équilibre n’a pas été atteint après dix jours et huit prélèvements. Le contenu en matière organique et l’activité microbienne semblent responsables de la modification des concentrations en métaux au cours de ces prélèvements, notamment, dans l’horizon FH où les microlysimètres performent très mal. En revanche, dans l’horizon B, les concentrations tendent à se stabiliser vers la fin de la série de prélèvements en se rapprochant des valeurs de référence. Bien que des valeurs plus élevées s’observent pour les microlysimètres, leurs concentrations en métaux sont comparables à celles des méthodes de référence (extrait à l’eau, lysimètres de terrain avec et sans tension). En somme, les microlysimètres se comportent généralement mieux dans l’horizon B. Même si leur utilisation est plus optimale dans un sol sableux, cet horizon est privilégié pour de futures études sur le terrain avec les microlysimètres.

Studies on the Production, Properties and Processability of Low Protein Latex

Latex protein allergy is a serious problem faced by users of natural rubber latex products. This is severe in health care workers, who are constantly using latex products like examination gloves, surgical gloves etc. Out of the total proteins only a small fraction is extractable and only these proteins cause allergic reactions in sensitized people. Enzymic deproteinisation of latex and leaching and chlorination of latex products are the common methods used to reduce the severity of the problem.Enzyme deproteinisation is a cubersome process involving high cost and process loss.Physical properties of such films are poor. Leaching is a lengthy process and in leached latex products presence of extractable proteins is observed on further storing. Chlorination causes yellowing of latex products and reduction in tensile properties.In this context a more simple process of removal of extractable proteins from latex itself was investigated. This thesis reports the application of poly propylene glycol (PPG) to displace extractable proteins from natural latex. PPG is added to 60 % centrifuged natural latex to the extent of 0.2 % m/rn, subssequently diluted to 30 % dry rubber content and again concentrated to obtain a low protein latex.Dilution of concentrated latex and subsequent concentration lead to a total reduction in non - rubber solids in the concentrate, especially proteins and reduction in the ionic concentration in the aqueous phase of the latex. It has been reported that proteins in natural rubber / latex affect its behaviour in the vulcanisation process. Ionic concentration in the aqueous phase of latex influence the stability, viscosity and flow behaviour of natural latex. Hence, a detailed technological evaluation was carried out on this low protein latex. In this study, low protein latex was compared with single centrifuged latex ( the raw material to almost every latex product), double centrifuged latex ( because dilution and second concentration of latex is accompanied by protein removal to some extent and reduction in the ionic concentration of the aqueous phase of latex.). Studies were conducted on Sulphur cure in conventional and EV systems under conditions of post ~ cure and prevulcanisation of latex. Studies were conducted on radiation cure in latex stage. Extractable protein content in vulcanised low protein latex films are observed to be very low. lt is observed that this low protein latex is some what slower curing than single centrifuged latex, but faster than double centrifuged latex. Modulus of low protein latex films were slightly low. In general physical properties of vulcanised low protein latex films are only siightly lower than single centrifuged latex. Ageing properties of the low protein latex films were satisfactory. Viscosity and flow behaviour of low protein latex is much better than double centrifuged latex and almost comparable to single centrifuged latex. On observing that the physical properties and flow behaviour of low protein latex was satisfactory, it was used for the preparation of examination gloves and the gloves were evaluated. It is observed that the properties are conforming to the Indian Standard Specifications. It is thus observed that PPG treatment of natural latex is a simple process of preparing low protein latex. Extractable protein content in these films are very low.The physical properties of the films are comparable to ordinary centrifuged latex and better than conventionally deprotenized latex films. This latex can be used for the production of examination gloves.

Seismic behavior of capacity designed masonry walls in low seismicity regions

Eurocode 8 representing a new generation of structural design codes in Europe defines ‎requirements for the design of buildings against earthquake action. In Central and ‎Western Europe, the newly defined earthquake zones and corresponding design ground ‎acceleration values, will lead in many cases to earthquake actions which are remarkably ‎higher than those defined so far by the design codes used until now in Central Europe. ‎ In many cases, the weak points of masonry structures during an earthquake are the corner ‎regions of the walls. Loading of masonry walls by earthquake action leads in most cases ‎to high shear forces. The corresponding bending moment in such a wall typically causes a ‎significant increase of the eccentricity of the normal force in the critical wall cross ‎section. This in turn leads ultimately to a reduction of the size of the compression zone in ‎unreinforced walls and a high concentration of normal stresses and shear stresses in the ‎corner regions. ‎ Corner-Gap-Elements, consisting of a bearing beam located underneath the wall and ‎made of a sufficiently strong material (such as reinforced concrete), reduce the effect of ‎the eccentricity of the normal force and thus restricts the pinching effect of the ‎compression zone. In fact, the deformation can be concentrated in the joint below the ‎bearing beam. According to the principles of the Capacity Design philosophy, the ‎masonry itself is protected from high stresses as a potential cause of brittle failure. ‎ Shaking table tests at the NTU Athens Earthquake Engineering Laboratory have proven ‎the effectiveness of the Corner-Gap-Element. The following presentation will cover the ‎evaluation of various experimental results as well as a numerical modeling of the ‎observed phenomena.‎

Magnetic interactions between transition metal impurities and clusters mediated by low-dimensional metallic hosts: A first principles theoretical investigation

The magnetic properties and interactions between transition metal (TM) impurities and clusters in low-dimensional metallic hosts are studied using a first principles theoretical method. In the first part of this work, the effect of magnetic order in 3d-5d systems is addressed from the perspective of its influence on the enhancement of the magnetic anisotropy energy (MAE). In the second part, the possibility of using external electric fields (EFs) to control the magnetic properties and interactions between nanoparticles deposited at noble metal surfaces is investigated. The influence of 3d composition and magnetic order on the spin polarization of the substrate and its consequences on the MAE are analyzed for the case of 3d impurities in one- and two-dimensional polarizable hosts. It is shown that the MAE and easy- axis of monoatomic free standing 3d-Pt wires is mainly determined by the atomic spin-orbit (SO) coupling contributions. The competition between ferromagnetic (FM) and antiferromagnetic (AF) order in FePtn wires is studied in detail for n=1-4 as a function of the relative position between Fe atoms. Our results show an oscillatory behavior of the magnetic polarization of Pt atoms as a function of their distance from the magnetic impurities, which can be correlated to a long-ranged magnetic coupling of the Fe atoms. Exceptionally large variations of the induced spin and orbital moments at the Pt atoms are found as a function of concentration and magnetic order. Along with a violation of the third Hund’s rule at the Fe sites, these variations result in a non trivial behavior of the MAE. In the case of TM impurities and dimers at the Cu(111), the effects of surface charging and applied EFs on the magnetic properties and substrate-mediated magnetic interactions have been investigated. The modifications of the surface electronic structure, impurity local moments and magnetic exchange coupling as a result of the EF-induced metallic screening and charge rearrangements are analysed. In a first study, the properties of surface substitutional Co and Fe impurities are investigated as a function of the external charge per surface atom q. At large inter-impurity distances the effective magnetic exchange coupling ∆E between impurities shows RKKY-like oscillations as a function of the distance which are not significantly affected by the considered values of q. For distances r < 10 Å, important modifications in the magnitude of ∆E, involving changes from FM to AF coupling, are found depending non-monotonously on the value and polarity of q. The interaction energies are analysed from a local perspective. In a second study, the interplay between external EF effects, internal magnetic order and substrate-mediated magnetic coupling has been investigated for Mn dimers on Cu(111). Our calculations show that EF (∼ 1eV/Å) can induce a switching from AF to FM ground-state magnetic order within single Mn dimers. The relative coupling between a pair of dimers also shows RKKY-like oscillations as a function of the inter-dimer distance. Their effective magnetic exchange interaction is found to depend significantly on the magnetic order within the Mn dimers and on their relative orientation on the surface. The dependence of the substrate-mediated interaction on the magnetic state of the dimers is qualitatively explained in terms of the differences in the scattering of surface electrons. At short inter-dimer distances, the ground-state configuration is determined by an interplay between exchange interactions and EF effects. These results demonstrate that external surface charging and applied EFs offer remarkable possibilities of manipulating the sign and strength of the magnetic coupling of surface supported nanoparticles.

Corticosterone plasma concentrations in Carioca High- and Low-Conditioned freezing rats after a fear conditioned task

Our group in the Psychology Department at Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio) developed a rat genetic model of extreme freezing in response to contextual cues in an experimental chamber previously associated with footshock. One of the lines, Carioca High Freezing (CHF), exhibits an enhanced conditioned freezing response, whereas the other line, Carioca Low Freezing (CLF), shows the opposite response. The present study investigated corticosterone concentration between these two lines of animals and a random (RND) line of rats both under basal conditions and test condition after an emotional challenge using a contextual fear conditioning protocol. Comparisons between basal and test plasma corticosterone concentrations suggested differential basal and fear-induced differences between the two lines. The differences between basal conditions is an important and relevant aspect to be considered in behavioral experiments using or assessing stress and could help to understand variability in naïve populations.

Preferred structures in large-scale circulation and the effect of doubling greenhouse gas concentration in HadCM3

Preferred structures in the surface pressure variability are investigated in and compared between two 100-year simulations of the Hadley Centre climate model HadCM3. In the first (control) simulation, the model is forced with pre-industrial carbon dioxide concentration (1×CO2) and in the second simulation the model is forced with doubled CO2 concentration (2×CO2). Daily winter (December-January-February) surface pressures over the Northern Hemisphere are analysed. The identification of preferred patterns is addressed using multivariate mixture models. For the control simulation, two significant flow regimes are obtained at 5% and 2.5% significance levels within the state space spanned by the leading two principal components. They show a high pressure centre over the North Pacific/Aleutian Islands associated with a low pressure centre over the North Atlantic, and its reverse. For the 2×CO2 simulation, no such behaviour is obtained. At higher-dimensional state space, flow patterns are obtained from both simulations. They are found to be significant at the 1% level for the control simulation and at the 2.5% level for the 2×CO2 simulation. Hence under CO2 doubling, regime behaviour in the large-scale wave dynamics weakens. Doubling greenhouse gas concentration affects both the frequency of occurrence of regimes and also the pattern structures. The less frequent regime becomes amplified and the more frequent regime weakens. The largest change is observed over the Pacific where a significant deepening of the Aleutian low is obtained under CO2 doubling.

Uneven distribution of nutrients in the root zone affects the incidence of blossom end rot and concentration of calcium and potassium in fruits of tomato

Tomato plants ( Lycopersicon esculentum Mill. var. DRK) were grown hydroponically to determine the effect of an uneven distribution of nutrients in the root zone on blossomend rot (BER) and Ca and K concentrations in the fruits. The plants were grown in rockwool with their root system divided into two portions. Each portion was irrigated with nutrient solutions with either the same or the different electrical conductivity (EC) in the range 0 to 6 dS m(-1). Solutions with high EC supplied to both sides of the root system significantly increased the incidence of BER. However, when only water or a solution of low EC was supplied to one portion, BER was reduced by 80%. Fruit yields were significantly higher ( P < 0.01) for plants that received solutions of the uneven EC treatments (6/0 or 4.5/0 EC treatment). Plants supplied with solutions of uneven EC generally had higher leaf and fruit concentrations of Ca but lower concentrations of K than those supplied with solutions of high EC. There was no difference in Ca concentration at the distal end of young fruits of the uneven EC treatment but it was reduced in the high EC treatments. The concentration of K in the mature fruits of the uneven EC treatments was lower than that of the high EC treatments and higher or similar that of the 3/3 or 2.5/2.5 EC treatments ( controls). A clear relationship was found between the incidence of BER and the exudation rate. High rate of xylem exudation was observed in the uneven EC treatments. Reduction of BER in the uneven EC treatments is most likely to be the effect of high exudation rate on Ca status in the young fruits. It was concluded that high EC of solution had positive effects on Ca concentration and incidence of BER provided that nutrient solution with low EC or water is supplied to the one portion of the root system.

Carbon dioxide induced stomatal closure increases radiative forcing of climate via a rapid reduction in low cloud

We performed an ensemble of twelve five-year experiments using a coupled climate-carbon-cycle model with scenarios of prescribed atmospheric carbon dioxide concentration; CO2 was instantaneously doubled or quadrupled at the start of the experiments. Within these five years, climate feedback is not significantly influenced by the effects of climate change on the carbon system. However, rapid changes take place, within much less than a year, due to the physiological effect of CO2 on plant stomatal conductance, leading to adjustment in the shortwave cloud radiative effect over land, due to a reduction in low cloud cover. This causes a 10% enhancement to the radiative forcing due to CO2, which leads to an increase in the equilibrium warming of 0.4 and 0.7 K for doubling and quadrupling. The implications for calibration of energy-balance models are discussed.

Effects of dietary vitamin A concentration of roasted soybean inclusion on marbling, adipose cellularity, and fatty acid composition of beef

A feedlot trial was conducted to determine the effect of dietary vitamin A concentration and roasted soybean (SB) inclusion on carcass characteristics, adipose tissue cellularity, and muscle fatty acid composition. Angus-crossbred steers (n = 168; 295 +/- 1.8 kg) were allotted to 24 pens (7 steers each). Four treatments, in a 2 x 2 factorial arrangement, were investigated: no supplemental vitamin A, no roasted soybeans (NANS); no vitamin A, roasted SB (20% of the diet on a DM basis; NASB); with supplemental (2,700 IU/kg) vitamin A, no roasted SB (WANS); and with supplemental vitamin A, roasted SB (WASB). Diets included high moisture corn, 5% corn silage, 10 to 20% supplement, and 20% roasted SB in the SB treatments on a DM basis. The calculated vitamin A concentration in the basal diet was < 1,300 IU/kg of DM. Blood samples (2 steers/pen) were collected for serum vitamin A determination. Steers were slaughtered after 168 d on feed. Carcass characteristics and LM composition were determined. Fatty acid composition of LM was analyzed, and adipose cellularity in the i.m. and s.c. depots was determined. No vitamin A x SB interactions were detected (P > 0.10) for cattle performance, carcass composition, or muscle fatty acid composition. Low vitamin A diets (NA) did not affect (P > 0.05) ADG, DMI, or G:F. Quality grade tended (P = 0.07) to be greater in NA steers. Marbling scores and the percentage of carcasses grading > or = Choice(-) were 10% greater for NA steers, although these trends were not significant (P = 0.11 and 0.13, respectively). Backfat thickness and yield grade were not affected (P > 0.26) by vitamin A supplementation. Composition of the LM was not affected (P > 0.15) by vitamin A or SB supplementation. Serum retinol at slaughter was 44% lower (P < 0.01) for steers fed NA than for steers supplemented with vitamin A (23.0 vs. 41.1 microg/dL). A vitamin A x SB interaction occurred (P < 0.05) for adipose cellularity in the i.m. depot; when no SB was fed, vitamin A supplementation decreased cell density and increased cell size. However, when SB was fed, vitamin A supplementation did not affect adipose cellularity. Adipose cellularity at the s.c. depot was not affected (P > 0.18) by vitamin A or SB treatments. Fatty acid profile of the LM was not affected by vitamin A (P > 0.05), but SB increased (P < 0.05) PUFA (7.88 vs. 4.30 g/100 g). It was concluded that feeding NA tended to increase marbling without affecting back-fat and yield grade. It appeared that NA induced hyperplasia in the i.m. but not in the s.c. fat depot.

Uneven distribution of nutrients in the root zone affects the incidence of blossom end rot and concentration of calcium and potassium in fruits of tomato

Tomato plants ( Lycopersicon esculentum Mill. var. DRK) were grown hydroponically to determine the effect of an uneven distribution of nutrients in the root zone on blossomend rot (BER) and Ca and K concentrations in the fruits. The plants were grown in rockwool with their root system divided into two portions. Each portion was irrigated with nutrient solutions with either the same or the different electrical conductivity (EC) in the range 0 to 6 dS m(-1). Solutions with high EC supplied to both sides of the root system significantly increased the incidence of BER. However, when only water or a solution of low EC was supplied to one portion, BER was reduced by 80%. Fruit yields were significantly higher ( P < 0.01) for plants that received solutions of the uneven EC treatments (6/0 or 4.5/0 EC treatment). Plants supplied with solutions of uneven EC generally had higher leaf and fruit concentrations of Ca but lower concentrations of K than those supplied with solutions of high EC. There was no difference in Ca concentration at the distal end of young fruits of the uneven EC treatment but it was reduced in the high EC treatments. The concentration of K in the mature fruits of the uneven EC treatments was lower than that of the high EC treatments and higher or similar that of the 3/3 or 2.5/2.5 EC treatments ( controls). A clear relationship was found between the incidence of BER and the exudation rate. High rate of xylem exudation was observed in the uneven EC treatments. Reduction of BER in the uneven EC treatments is most likely to be the effect of high exudation rate on Ca status in the young fruits. It was concluded that high EC of solution had positive effects on Ca concentration and incidence of BER provided that nutrient solution with low EC or water is supplied to the one portion of the root system.

Mechanisms by which cysteine can inhibit or promote the oxidation of low density lipoprotein by copper

Oxidised low density lipoprotein (LDL) may play a role in atherogenesis. We have investigated some of the mechanisms by which the thiol cysteine and the disulphide cystine can influence the oxidation of LDL by copper ions. Cysteine or cystine (100 PM) inhibited the oxidation of native LDL by copper in a simple phosphate buffer. One of the mechanisms by which cysteine (or more likely its oxidation products in the presence of copper) and cystine inhibited LDL oxidation was by decreasing the binding of copper to LDL (97% inhibition). Cysteine, but not cystine, rapidly reduced Cu2+ to Cu+. This may help to explain the antioxidant effect of cysteine as it may limit the amount of Cu2+ that is available to convert alpha-tocopherol in LDL into the prooxidant alpha-tocopherol radical. Cysteine (but not cystine) had a prooxidant effect, however, toward partially oxidised LDL in the presence of a low copper concentration, which may have been due to the rapid breakdown of lipid hydroperoxides in partially oxidised LDL by Cu+ generated by cysteine. To prove that cysteine can cause the rapid breakdown of lipid hydroperoxides in LDL, we enriched LDL with lipid hydroperoxides using an azo initiator in the absence of copper. Cysteine, but not cystine, increased the rate of lipid hydroperoxide decomposition to thiobarbituric acid-reactive substances (TBARS) in the presence of copper. (C) 2003 Elsevier Ireland Ltd. All rights reserved.