20 research outputs found
Polymeric Complexes of Cornstarch and Waxy Cornstarch Phosphates with Milk Casein and Their Performance as Biodegradable Materials
Abstract. Complexes of phosphated cornstarch and waxy cornstarch with casein were prepared and characterised. They were prepared from casein in defatted milk and corn and waxy corn starches phosphated to degree of substitution values (DS) of 0.0637 and 0.0968, respectively. The components were blended in starch to casein ratios of 2:1, 1:1, and 1:2, then precipitated with hydrochloric acid. Aqueous solubility, water binding capacity, IR spectra, and thermal analysis (thermogravimetry, TG, and differential thermogravimetry, DTG) of the precipitates revealed that they were not simple physical mixtures of the components. The components interact with one another electrostatically with involvement of the starch phosphate groups and the peptide bonds of casein as documented by the IR spectra. Because of their insolubility in 7 M aqueous urea solution they might also be considered as complexes in which the components were chemically bound. Enzymatic studies showed that they are biodegradable materials
Application of Acid Whey in Orange Drink Production
Svrha je ovoga rada bila usporediti kvalitetu napitaka od naranče s onom napitaka od naranče i sirutke tijekom 12 mjeseci skladištenja. Napici su sadržavali 12 % ekstrakta, od čega je polovina bila koncentrat naranče. Za proizvodnju napitaka sa sirutkom dodano je 50 % sirutke od ukupne količine dodane vode. Napici od naranče sa sirutkom imali su veći udjel proteina, pepela, glukoze, laktoze i vitamina B2, no manji udjel saharoze, fruktoze i vitamina C, te manju sposobnost uklanjanja DPPH radikala od napitaka napravljenih samo s narančom. Nisu pronađene bitne razlike u udjelu polifenola ili sposobnosti uklanjanja ABTS kationa između ta dva tipa napitaka. Parametri boje mjereni prema CIE sustavu uvelike su se razlikovali, iako je prema senzorskoj procjeni prihvatljivost boje napitaka bila gotovo ista. Sveukupna ocjena senzorske kakvoće napitaka od naranče sa sirutkom bila je 2-10 % lošija od napitaka napravljenih samo s narančom. Intenzitet okusa naranče, te slatke i osvježavajuće arome napitaka od naranče bili su veći u tim napicima nego u onima od naranče i sirutke, u kojima su prevladavali kiseli okus i aroma sirutke. Tijekom skladištenja znatno su se smanjili udjeli saharoze i laktoze, antioksidativna aktivnost, senzorska kakvoća, intenzitet arome naranče, te kiseli i osvježavajući okus napitaka sa sirutkom, dok su se povećali udjeli glukoze i fruktozeThe aim of this study is to compare qualitative changes in orange and orange beverages containing whey during 12 months of storage. The beverages contained 12 % extract, half of which was orange concentrate, the rest was sugar or sugar and whey extract. Acid whey was used in the production of beverages, added at a rate of 50 % of the used water. Orange beverages with whey contained more protein, ash, glucose, lactose and vitamin B2 than the orange beverages, but less sucrose, fructose and vitamin C, and also showed lower antioxidant activity against the DPPH radical. No significant differences between the two types of beverages were found in the polyphenolic content or activity against the ABTS cation radical. The type of beverage had a significant effect on the colour parameter values under the CIELAB system, although no significant differences were found between the beverages in the sensory evaluation of colour desirability. The overall sensory evaluation of orange beverages with whey was 2–10 % lower than of other orange beverages. The intensity of orange, sweet and refreshing taste was greater in orange beverages, while that of sour and whey taste was greater in orange beverages containing whey. There were significant decreases in sucrose, lactose, all indicators of antioxidant activity and sensory quality during storage. Levels of glucose and fructose rose with the storage period, while the intensity of sour, orange and refreshing taste decreased
Seronegative Infection with Toxoplasma gondii in Asymptomatic Human Immunodeficiency Virus Type 1 (HIV-1)-Infected Patients and in Blood Donors
Background: Toxoplasmosis is a common opportunistic infection in AIDS patients. The routine diagnostics is based on serologic testing and IgG avidity index, but it may have limited utility in immunodeficient patients; thus, it is recommendable to detect T. gondii DNA in subjects with advanced HIV disease. The results of the studies published so far focused on patients with clinical symptoms of toxoplasmosis. Our study encompassed a group of HIV-infected subjects on cART therapy, without immunological disturbances and clinical symptoms of T. gondii infection. Methods: The study was retrospective, and samples were collected between 2013 and 2016. We evaluate the prevalence of serological (IgM, IgG, and avidity IgG) and molecular (DNA) T. gondii infection markers in asymptomatic HIV-infected patients and the control group using serologic (ELISA) and quantitative (real-time PCR) molecular testing. Results: Of 152 HIV-infected in routine follow-up tested for T. gondii IgM and IgG, 6 (3.9%) and 50 (32.9%) were positive, respectively. Of 168 serum samples from blood donors, 1 (0.6%) and 49 (29.2%) were IgM+ and IgG+ positive, respectively. IgM seroprevalence in HIV-infected patients was significantly higher than in blood donors. T. gondii DNA (genotype II) was identified in 47 (30.9%) HIV-infected patients, with 13 (8.6%) IgM−IgG− samples. In blood donors, T. gondii DNA was present in 15 (8.9%) IgM−IgG−. Conclusions: In both groups, T. gondii DNA was detectable in seronegative subjects, implying the need to supplement the routine serological testing via the molecular method. It can help the accurate monitoring of the reactivation of infection in asymptomatic HIV-infected persons, and the quick introduction of specific therapy, in blood donors, would be of high importance for safe blood donations
Automatic air volume control system for ventilation of two patients using a single ventilator: a large animal model study
Abstract The COVID-19 pandemic outbreak led to a global ventilator shortage. Hence, various strategies for using a single ventilator to support multiple patients have been considered. A device called Ventil previously validated for independent lung ventilation was used in this study to evaluate its usability for shared ventilation. We performed experiments with a total number of 16 animals. Eight pairs of pigs were ventilated by a ventilator or anesthetic machine and by Ventil for up to 27 h. In one experiment, 200 ml of saline was introduced to one subject’s lungs to reduce their compliance. The experiments were analyzed in terms of arterial blood gases and respiratory parameters. In addition to the animal study, we performed a series of laboratory experiments with artificial lungs (ALs). The resistance and compliance of one AL (affected) were altered, while the tidal volume (TV) and peak pressure (Ppeak) in the second (unaffected) AL were analyzed. In addition, to assess the risk of transmission of pathogens between AL respiratory tracts, laboratory tests were performed using phantoms of virus particles. The physiological level of analyzed parameters in ventilated animals was maintained, except for CO2 tension, for which a permissive hypercapnia was indicated. Experiments did not lead to injuries in the animal’s lungs except for one subject, as indicated by CT scan analysis. In laboratory experiments, changes in TV and Ppeak in the unaffected AL were less than 11%, except for 2 cases where the TV change was 20%. No cross-contamination was found in simulations of pathogen transmission. We conclude that ventilation using Ventil can be considered safe in patients undergoing deep sedation without spontaneous breathing efforts