Posttraumatic stress disorder symptoms and family functioning in adult children facing parental cancer: a comparison study

This study analyzed posttraumatic stress disorder (PTSD) symptoms and family functioning in a sample of adult children caregivers of cancer patients and in a group of adult children of nonchronically ill parents. Participants completed measures of family functioning and PTSD symptoms. The parental cancer group was subdivided into PTSD subgroups, and significant differences, on family functioning, were found. In the parental cancer group, the predictors of PTSD symptoms were being a woman and having an enmeshed or chaotic family functioning. Chaotic functioning mediated the relationship between family communication/satisfaction and PTSD symptoms, in the parental cancer group. Finally, there was a higher prevalence of PTSD symptoms in the parental cancer group, and participants with a probable PTSD diagnosis showed higher levels of family imbalance. This study shows that adult children facing parental cancer, who have a poorer family balance, may benefit from interventions that target family functioning.This research was supported by a grant (SFRH/BD/43275/2008) awarded to the first author (RJT) by the Portuguese Foundation for Science and Technology.info:eu-repo/semantics/publishedVersio

Denaturation of whey proteins of milk during ohmic heating

Ohmic heating has often been said to improve the sensorial quality of foodstuffs, which has been ttributed mainly to its volumetric heating mechanism and (eventually) to the presence of an electric field. This is still subject to doubts and questions from the scientific community, and it is therefore important to determine the effect of ohmic heating on food constituents. We have investigated whether ohmic heating technology would give rise to changes on the denaturation of whey proteins from bovine milk. Whey protein solutions samples were heated at 85 ºC (up to 30 min) and ohmic heating experiments were also adapted to simulate the sample temperature changes during conventional (indirect heating) experiments. Our results show that ohmic heating seems to reduce protein unfolding and denaturation, when compared with conventional heating

Exploring the denaturation of whey proteins upon application of moderate electric fields : a kinetic and thermodynamic study

Thermal processing often results in disruption of the native conformation of whey proteins, thus affecting functional properties. The aim of this work was to evaluate the effects of moderate electric fields on denaturation kinetics and thermodynamic properties of whey protein dispersions at temperatures ranging from 75 to 90 °C. Application of electric fields led to a lower denaturation of whey proteins, kinetically traduced by lower values of reaction order (n) and rate constant (k) (p 30% of native soluble protein than conventional heating) and has determined also considerable changes in calculated thermodynamic properties (such as Ea, ΔH, ΔS). In general, denaturation reactions during moderate electric fields processing were less dependent on temperature increase.RNP gratefully acknowledges a doctoral grant (SFRH/BD/31635/2006) from the Fundacao para Ciencia e Tecnologia (FCT, Portugal

Influence of moderate electric fields on the formation and properties of whey protein network structures

Gelation plays a major role in enhancing textural properties of foods (substituting fats), once it provides unique textural properties that gives pleasant mouth feel, and enables holding water and other ingredients in one matrix. The general objective of this study was to assess the effects of MEF on properties of whey protein hydrogels. Results show that MEF originated a weaker gel structure than conventional heating treatment. Significant decreases in storage and loss moduli were observed upon application of MEF. Aggregation and cross-linking patterns of whey proteins during MEF was not sufficiently high to form a true elastic gel network. As conclusion, MEF may provide a novel method for production of a protein matrix with distinctive properties. However a larger body of research is needed to fully address the role of the MEF on protein electrostatics and protein-protein interactions

Effects of moderate electric fields (MEF) on denaturation of whey proteins solutions

Electric fields application during thermal processing are now receiving increased attention due to uniform heating of liquids and extremely rapid heating rates, which presumably enables higher temperatures to be applied without inducing excessive denaturation of the constituent proteins [1]. The aim of this work was to evaluate the effects of moderate electric fields (MEF) on denaturation kinetics and thermodynamic properties of whey protein dispersions at temperatures ranging from 75 to 90 ºC. Application of MEF led to a lower denaturation of whey proteins, kinetically traduced by lower values of reaction order (n) and rate constant (k) (p 30% of native soluble protein than conventional heating). In general, denaturation reactions during MEF were less dependent on temperature increase presenting higher values of ΔG# in the range of temperatures studied. Further, MEF produced smaller changes (p < 0.05) in whey protein aggregates’ size when compared with a conventional heating MEF offers the potential to change the functional and technological properties of whey proteins, by changing their degree of denaturation. An accurate selection of the MEF process variables may allow controlling the size of protein nanoparticles. These findings could open novel perspectives on the use of OH not only in food and bioprocessing applications, but also in the pharmaceutical area

First reports of computed tomographic colonography for the screening of colorectal polyps in acromegalic patients

*Aim:* To analyze the CTC performance for the screening of colorectal polyps in acromegalic patients. &#xd;&#xa;&#xd;&#xa;*Materials and Methods:* A prospective study of 21 acromegalic patients, 12 male and 9 female, average age 49, who underwent CTC and CC. CTC was performed with a GE Helical Multislice Computed Tomography Apparatus. The colonoscopy was performed, in the same day, without previous knowledge of the CTC diagnostics. The study evaluated the capacity of CTC to detect patients with colorectal polyps and identify each colorectal lesion described by CC. &#xd;&#xa;&#xd;&#xa;*Results:* In two patients (2/21), CC was incomplete. However, in all patients CTC was complete. In Phase I (&#x201c;Per Patient&#x201d;), CTC diagnosed 8 of the 9 patients with colorectal polyps and showed 88% sensitivity, 75% specificity and 81% accuracy. In Phase II (&#x201c;Per Polyp&#x201d;), out of the 21 acromegalic patients included in this study, 12 presented normal findings at CC. A total of 19 polyps were identified in 9 patients. 10 of the 19 polyps were smaller than 10 mm, and 9 were equal to or larger than 10. CTC identified 7 of the 9 polyps &#x2265; 10 mm described by CC and only 6 of the 10 small polyps identified at CC were detected by CTC. The histological analysis of resected lesions revealed 12 tubular adenomas, 6 hyperplastic polyps and 1 colonic tubulo-villous adenoma with an adenocarcinoma focus. &#xd;&#xa;&#xd;&#xa;*Conclusion:* In this study, CTC was performed without complications and a complete and safe colorectal evaluation was possible in all acromegalic patients. Moreover, CTC showed good sensitivity to identify acromegalic patients with colorectal polyps

Application of binary packing for starch separation by hydrodynamic chromatography

Columns packed with commercial glass beads of 5 and 19 microns average diameter and binary mixtures with finest fraction of 5 micron (30 % volume fraction of the mixture) were used to analyse starch by hydrodynamic chromatography (HDC). Experiments were carried out at 3 and 15 ºC. The observed resolution increased with the application of binary packing as compared with single-size packing. The best results were obtained at starch’s amylopectin and amylose separation with a glass beads mixture (5 + 19 micron) at 3ºC. In what concerns amylopectin and amylose separation, a lower pressure drop were obtained for the mixed binary packing when compared with the packing containing uniform 5 micron glass beads. For the Hylon VII starch RRT were 0.777 and 0.964 for amylopectin (AP) and amylose (AM), respectively, while for the Tapioca starch the obtained RRTs were 0.799 and 0.923. Application of unbound glass beads as column packing might reduce equipment and running costs in preparative scale separations.Fundação para a Ciência e a Tecnologia (FCT) .FEDER - projecto POCI_EQU_58337/200

Tortuosity variation in a low density binary particulate bed

The importance of particle size ratio and particle composition in the properties of a mixed bed is well known. Nevertheless, the dependence of the bed channel tortuosity T on the porosity ε in the form T=1/εn, where n is assumed to be a constant, shows that the value of n depends on the properties of the packed bed. For loose packing, experimental data for binary mixtures of glass beads of a size ratio from 1 up to 53.8 was analysed in terms of porosity, tortuosity and permeability. The packing procedure was performed without intensive compacting methods e.g. vibration, etc. Obtained results show that the parameter n is a function of the volume fraction of large particles xD and, for spherical particles, lies in the range 0.4–0.5. The explanation for this variation is (1) a distortion effect on the small particles arrangement occurring near the large particle surface; (2) in the region of minimum porosity, near contact points of large particles, the occurrence of dead zones that are free of small particles. A relationship accounting for this effect is proposed that may be useful for the analysis of transport phenomena in granular bed filters, chromatographic columns, etc.Fundação para a Ciência e a Tecnologia FCT); FEDE

Effect of real particles packing with large size ratio on porosity and tortuosity of filter bed

The complexity of processes involved in the formation of granular beds results in limited information about permeability κ , which directly rela tes with packing porosity ε and tortuosity T . For a mixed bed of particles significantly different in size, the influence of packing affects permeability. For a better understanding of the underlying relationship between κ , ε , and T in mixed beds of particles significantly different in size, simplified porous media model of binary mixture of spheres were used. Boundary analysis of the binary packing showed that the approach based on the fractional porosity of large and small size particle fractions gives a tool for ε control. This approach allows a new insight into the mixture structure and provides explanation for the different types of the obtained porosity. Binary packing of glass beads with size ratios 13.3, 20, and 26.7 were investigated. As a basic relation for the dependence of T on ε, at different volume fraction xD of large particles in the mixture, the formula T=1/ εⁿ was used. The obtained experimental results show that the parameter n is a function of the packing content xD and may vary in the range of 0.4-0.5. The reason for n variation was explained by the wall effect of the small particles arrangement occurring near the large particles surface. A model accounting for this effect is proposed and may be useful for transport phenomena analysis in granular bed filters.Fundação para a Ciência e a Tecnologia (FCT) – Programa Operacional “Ciência, Tecnologia, Inovação” (POCTI) - POCTI/EQU/37500/2001.União Europeia (UE). Fundo Europeu de Desenvolvimento Regional (FEDER)

Particulate binary mixtures : dependence of packing porosity on particle size ratio

Binary mixtures with significant size ratios are scarcely studied. Yet, contaminants of chromatographic columns or ion-exchange resins have size ratios of delta < 0.1. Binary mixtures of glass beads with delta = 0.1-0.0375 were used experimentally to measure packing porosity. Simultaneously, a significant number of published data was analyzed. A linear mixing model was adopted to predict the porosity of each particle fraction in the binary mixture. Deviations from the model may be caused by wedging of small particles between the large ones. Large particles may disturb the porous medium properties by inducing a wall effect over the small particles. Wedging analysis led to the conclusion that, for delta < 0.01, its effect is insignificant. The wall effect yields an additional void around the large particles as long as delta > 0.0035. For delta < 0.0035, the small particles form a monosized dense packing and both wedging and wall effects become negligible.Fundação para a Ciência e a Tecnologia (FCT) e FEDER – POCTI/EQU/37500/2001