Lipid hydroperoxide-induced and hemoglobin-enhanced oxidative damage to colon cancer cells

Epidemiological studies have indicated that Western diets are related to an increase in a series of malignancies. Among the compounds that are credited for this toxic effect are heme and lipid peroxides. We evaluated the effects of hemoglobin (Hb) and linoleic acid hydroperoxides (LAOOH) on a series of toxicological endpoints, such as cytotoxicity, redox status, lipid peroxidation, and DNA damage. We demonstrated that the preincubation of SW480 cells with Hb and its subsequent exposure to LAOOH (Hb + LAOOH) led to an increase in cell death, DCFH oxidation, malonaldehyde formation, and DNA fragmentation and that these effects were related to the peroxide group and the heme present in Hb. Furthermore, Hb and LAOOH alone exerted a toxic effect on the endpoints assayed only at concentrations higher than 100 mu M. We were also able to show that SW480 cells presented a higher level of the modified DNA bases 8-oxo-7,8-dihydro-2`-deoxyguanosine and 1,N(2)-etheno-2`-deoxyguanosine compared to the control. Furthermore, incubations with Hb led to an increase in intracellular iron levels, and this high level of iron correlated with DNA oxidation, as measured as EndoIII- and Fpg-sensitive sites. Thus, Hb from either red meat or bowel bleeding could act as an enhancer of fatty acid hydroperoxide genotoxicity, which contributes to the accumulation of DNA lesions in colon cancer cells. (C) 2011 Elsevier Inc. All rights reserved.

Novel immunoadjuvants based on cationic lipid: Preparation, characterization and activity in vivo

The interactions between three different protein antigens and dioctadecyldimethylammonium bromide (DODAB) dispersed in aqueous solutions from probe sonication or adsorbed its one bilayer onto particles was comparatively investigated. The three model proteins were bovine serum albumin (BSA), purified 18 kDa/14 kDa antigens from Taenia crassiceps (18/14-Tcra) and a recombinant, heat-shock protein hsp-18 kDa from Mycobacterium leprae. Protein-DODAB complexes in water solution were characterized by dynamic light scattering for sizing and zeta-potential analysis. Cationic complexes (80-100 nm of mean hydrodynamic diameter) displayed sizes similar to those of DODAB bilayer fragments (BF) in aqueous solution and good colloid stability over a range of DODAB and protein concentrations. The amount of cationic lipid required for attaining zero of zeta-potential at a given protein amount depended on protein nature being smaller for 18 kDa/14 kDa antigens than for BSA. Mean diameters for DODAB/protein complexes increased, whereas zeta-potentials decreased with NaCl or protein concentration. In mice, weak IgG production but significant cellular immune responses were induced by the complexes in comparison to antigens alone or carried by aluminum hydroxide as shown from IgG in serum determined by ELISA, delayed type hypersensitivity reaction from footpad swelling tests and cytokines analysis. The novel cationic adjuvant/protein complexes revealed good colloid stability and potential for vaccine design at a reduced DODAB concentration. (C) 2009 Elsevier Ltd. All rights reserved.

Total phenolic content and free radical scavenging activities of methanolic extract powders of tropical fruit residues

Methanolic extract powders of acerola, passion fruit and pineapple industrial residues, including pulp, seeds and peel, altogether (except for acerola) devoid of seeds, were screened for antioxidant capacity. The total phenolic contents (TPCs) of the extract powders were compared with their radical-scavenging activities (RSA) against both DPPH(center dot) and superoxide anion (O(2)(center dot-)) radicals, and their protective effect against liposome peroxidation, triggered by peroxyl radical. Lipid peroxidation was followed by the fluorescence decay of the probe, 4,4-difluoro-5-(4-phenyl-1,3-butadienyl)-4-bora-3a,4a-diaza-s-indacene-3-undecanoic acid (C(11)-BODIPY(581/591)). The TPCs of acerola, passion fruit and pineapple extract powders were (94.6 +/- 7.4); (41.2 +/- 4.2) and (9.1 +/- 1.3) mg of gallic acid equivalents g(-1) of dry extract, respectively. Acerola showed the best RSA-DPPH(center dot) scores, whereas passion fruit was more protective on the RSA-O(2)(center dot-) system. Together with the protective effects against lipid peroxidation (rate of BODIPY decay) which, were similar for acerola and passion fruit extracts, these data suggest that the methanolic extracts of acerola and passion fruit residues may be useful as antioxidant supplements, particularly the acerola extract, due to its high phenolic content. (C) 2008 Elsevier Ltd. All rights reserved

Hybrid materials from intermolecular associations between cationic lipid and polymers

Intermolecular associations between a cationic lipid and two model polymers were evaluated from preparation and characterization of hybrid thin films cast on silicon wafers. The novel materials were prepared by spin-coating of a chloroformic solution of lipid and polymer on silicon wafer. Polymers tested for miscibility with the cationic lipid dioctadecyldimethylammonium bromide (DODAB) were polystyrene (PS) and poly(methyl methacrylate) (PMMA). The films thus obtained were characterized by ellipsometry, wettability, optical and atomic force microscopy, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and activity against Escherichia coli. Whereas intermolecular ion-dipole interactions were available for the PMMA-DODAB interacting pair producing smooth PMMA-DODAB films, the absence of such interactions for PS-DODAB films caused lipid segregation, poor film stability (detachment from the silicon wafer) and large rugosity. In addition, the well-established but still remarkable antimicrobial DODAB properties were transferred to the novel hybrid PMMA/DODAB coating, which is demonstrated to be highly effective against E. coli.

Salinity influences glutathione S-transferase activity and lipid peroxidation responses in the Crassostrea gigas oyster exposed to diesel oil

Biochemical responses in bivalve mollusks are commonly employed in environmental studies as biomarkers of aquatic contamination. The present study evaluated the possible influence of salinity (35, 25,15 and 9 ppt) in the biomarker responses of Crassostrea gigas oysters exposed to diesel at different nominal concentrations (0.01, 0.1 and 1 mLL(-1)) using a semi-static exposure system. Salinity alone did not resulted in major changes in the gill`s catalase activity (CAT), glutathione S-transferase activity (GST) and lipid peroxidation levels (measured as malondialdehyde. MDA), but influenced diesel related responses. At 25 ppt salinity, but not at the other salinity levels, oysters exposed to diesel showed a strikingly positive concentration-dependent GST response. At 25 ppt and 1 mLL(-1) diesel, the GST activity in the gills remained elevated, even after one week of depuration in clean water. The increased MDA levels in the oysters exposed to diesel comparing to control groups at 9, 15 and 35 ppt salinities suggest the occurrence of lipid peroxidation in those salinities, but not at 25 ppt salinity. The MDA quickly returned to basal levels after 24 h of depuration. CAT activity was unaltered by the treatments employed. High toxicity for 1 mLL(-1) diesel was observed only at 35 ppt salinity, but not in the other salinities. Results from this study strongly suggest that salinity influences the diesel related biomarker responses and toxicity in C. gigas, and that some of those responses remain altered even after depuration. (C) 2011 Elsevier B.V. All rights reserved.

Antimicrobial Particles from Cationic Lipid and Polyelectrolytes

Hybrid nanoparticles from cationic lipid and polymers were prepared and characterized regarding physical properties and antimicrobial activity. Carboxymethylcellulose (CMC) and polydiallyldimethylammonium chloride (PDDA) were sequentially added to cationic bilayer fragments (BF) prepared from ultrasonic dispersion in water of the synthetic and cationic lipid dioctadecyldimethylammonium bromide (DODAB). Particles thus obtained were characterized by dynamic light-scattering for determination of z-average diameter (Dz) and zeta-potential (zeta). Antimicrobial activity of the DODAB BF/CMC/PDDA particles against Pseudomonas aeruginosa or Staphylococcus aureus was determined by plating and CFU counting over a range of particle compositions. DODAB BF/CMC/PDDA particles exhibited sizes and zeta-potentials strictly dependent on DODAB, CM C, and PDDA concentrations. At 0.1 mM DODAB, 0.1 mg/mL CMC, and 0.1 mg/mL PDDA, small cationic particles with Dz = 100 nm and zeta = 30 mV were obtained. At 0.5 mM DODAB, 0.5 mg/mL CMC and 0.5 mg/mL PDDA, large cationic particles with Dz = 470 nm and zeta= 50 mV were obtained. Both particulates were highly reproducible regarding physical properties and yielded 0% of p. aeruginosa viability (10(7) CFU/mL) at 1 or 2 mu g/mL PDDA dissolved in solution or in form of particles, respectively. 99% of S. aureus cells died at 10 mu g/mL PDDA alone or in small or large DODAB BF/CMC/PDDA particles. The antimicrobial effect was dependent on the amount of positive charge on particles and independent of particle size. A high microbicide potency for PDDA over a range of nanomolar concentrations was disclosed. P. aeruginosa was more sensitive to all cationic assemblies than S. aureus.

Palliativa patienters livskvalitet vid behandling med parenteral nutrition : en litteraturöversikt

Syfte: Litteraturöversiktens syfte var att belysa vilken påverkan parenteral nutrition har på livskvaliteten hos palliativa patienter. Metod: Denna studie har genomförts som en litteraturöversikt. Vetenskapliga artiklar har insamlats från databaserna Cinahl, Medline och Pubmed. Totalt fann författarna 12 vetenskapliga artiklar som svarade mot litteraturstudiens syfte. De utvalda artiklarna var både kvantitativa och kvalitativa. Kvalitetsgranskningen utfördes med hjälp av granskningsmallar och artiklarna som lade grunden till resultatet motsvarade medel till hög kvalitet. Resultat: Resultatet visade på att flertalet patienter kände en trygghet och lättnad när den parenterala nutritionen introducerades. Patienterna ansåg att vetskapen att deras nutritionsbehov blev tillfredsställt gjorde att de inte behövde vara rädda för att svälta ihjäl. De upplevde en ökad livskvalitet då de slapp oroa sig för födointaget och orkade medverka mera aktivt i det sociala familjelivet. Flertalet av patienterna uppgav en förbättrad livskvalitet när möjlighet gavs att få parenteral nutrition i hemmet trots att det innebar inskränkningar i familjelivet. De uppgav även en ökad styrka till att hantera bland annat sjukdomssymtom och behandlingsbiverkningar. Den parenterala nutritionen gav i vissa fall problem med biverkningar, men de flesta patienterna skattade ändå livskvaliteten högre av att få näringsdroppet. Resultatet visade även på att om den parenterala nutritionen sattes in i ett tidigt skede kunde en förbättring av nutritionsstatusen ske och patienterna behöll sin kroppsvikt under en något längre tid. Det resulterade i en ökad skattning av livskvaliteten. De sista veckorna i livet hade näringsdroppet ingen mätbar positiv effekt.

Egenvård i nutrition till personer med hjärtsvikt.

Syfte:            Syftet med denna litteraturstudie var att studera hur personer med hjärtsvikt kan få en förbättrad nutrition genom egenvård. Metod:          Studien genomfördes som en litteraturöversikt. Artiklarna söktes via databaserna CINAHL och PubMed. Resultat:       Studiens resultat innehöll 10 artiklar med kvantitativ ansats. En förutsättning för att personer med hjärtsvikt ska klara sin egenvård och ges möjlighet att förbättra sin nutrition är utbildning. Utbildningsmetoder som i föreliggande litteraturstudie har visat sig fungera är att kombinera skriftlig och muntlig utbildning. Undervisningen bör innehålla information om vilken typ av mat personer med hjärtsvikt behöver äta samt varför. En god följsamhet till givna riktlinjer nås genom att ge personer med hjärtsvikt individuellt anpassad information samt att uppföljning sker och information ges kontinuerligt. Slutsats:        Det är mycket viktigt att hälso- och sjukvårdspersonal kombinerar muntlig och skriftlig information vid utbildning inom nutrition riktad till personer med hjärtsvikt för att stärka deras egenvård. Hälso- och sjukvårdspersonal bör se till att kontinuerlig uppföljning sker för att optimera följsamheten.  

Sjuksköterskors erfarenheter av parenteral nutrition för patienter i livets slutskede : En litteraturöversikt

Bakgrund: Tidigare forskning har visat att parenteral nutrition ges till patienter som befinner sig i livets slutskede även om den medicinska nyttan är oklar. Syfte: Att genom en vetenskaplig litteraturöversikt beskriva sjuksköterskors erfarenheter av vad som är betydelsefullt i arbetet med parenteral nutrition för patienter i livets slutskede. Metod: Examensarbetet är utformat som en litteraturöversikt. Tretton artiklar med kvalitativ och kvantitativ design valdes ut. Artiklarna söktes på databaserna CINAHL och Pubmed Resultat: Delaktighet i vårdteam var av stor betydelse, ett fungerade samarbete där sjuksköterskan ville och fick möjlighet att arbeta som omvårdnadsansvarig upplevdes av sjuksköterskan resultera i god personcentrerad vård. Erfarenhet och egna känslor spelar en betydande roll i hur mycket sjuksköterskan vågar och vill vara delaktig i beslut angående PN i livets slutskede, och vilken relation som skapas med patientens närstående. Slutsats: Ökad kunskap om parenteral nutrition i livets slutskede och personcentrerad vård behövs för att sjuksköterskorna ska våga vara aktivt delaktig och stärka patienten i livets slutskede.