Oxidative stability and consumer acceptance of fish oil fortified nutrition bars

Oat and soy-based nutrition bars were fortified with 4 levels of fish oil (0, 6, 12, or 18 g per approximately 600 g batch), representing 0%, 20%, 40%, or 60% replacement of canola oil. The commercially available purified fish oil was not emulsified nor encapsulated, and contained tocopherols. Baked nutrition bars were evaluated for proximate composition, water activity, alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic (DHA) content, and consumer acceptance using a 9-point hedonic scale. The bars were sealed in opaque bags and stored in a stability chamber at 25 °C and 50% relative humidity for 10 wk to assess oxidative stability. There were no significant (P > 0.05) differences in proximate composition, water activity, or ALA levels among treatments. EPA and DHA levels were significantly (P < 0.05) different among treatments, averaging 178.1 mg/serving (20-FO), 488.3 mg/serving (40-FO), and 664.6 mg/serving (60-FO), but none changed during storage. Headspace hexanal and propanal levels decreased over time but were not significantly different among treatments until week 10. Peroxide values were not significantly different except between the control and 60-FO bars. Low values obtained for these analyses suggest negligible oxidation in the bars. Consumer acceptance scores did not differ significantly between the control and lowest fortification level (20-FO), ranging from 6.4 to 6.6 for aroma, texture, flavor, and overall acceptability. These results suggest that nonemulsified, nonencapsulated fish oil can successfully replace canola oil in intermediate moisture nutrition bars to provide EPA and DHA levels as high as 178 mg/serving without affecting consumer acceptability or oxidative stability. Practical Application: Omega-3 fatty acid rich fish oil has been shown to have numerous health benefits, but there are limitations to its use in shelf-stable food products. In this study, nutrition bars were successfully fortified with nonencapsulated, nonemulsified fish oil to deliver 178 mg EPA and DHA per 35 g serving. The fortified bars were oxidatively stable over 10 wk and acceptable to consumers.     

On Command Drug Delivery via Cell‐Conveyed Phototherapeutics

Herein, the use of red blood cells (RBCs) as carriers of cytoplasmically interned phototherapeutic agents is described. Photolysis promotes drug release from the RBC carrier thereby providing the means to target specific diseased sites. This strategy is realized with a vitamin B12‐taxane conjugate (B12‐TAX), in which the drug is linked to the vitamin via a photolabile Co? C bond. The conjugate is introduced into mouse RBCs (mRBCs) via a pore‐forming/pore‐resealing procedure and is cytoplasmically retained due to the membrane impermeability of B12. Photolysis separates the taxane from the B12 cytoplasmic anchor, enabling the drug to exit the RBC carrier. A covalently appended Cy5 antenna sensitizes the conjugate (Cy5‐B12‐TAX) to far red light, thereby circumventing the intense light absorbing properties of hemoglobin (350–600 nm). Microscopy and imaging flow cytometry reveal that Cy5‐B12‐TAX‐loaded mRBCs act as drug carriers. Furthermore, intravital imaging of mice furnish a real time assessment of circulating phototherapeutic‐loaded mRBCs as well as evidence of the targeted photorelease of the taxane upon photolysis. Histopathology confirms that drug release occurs in a well resolved spatiotemporal fashion. Finally, acoustic angiography is employed to assess the consequences of taxane release at the tumor site in Nu/Nu‐tumor‐bearing mice.     

Systematic review of maintenance of behavior change following physical activity and dietary interventions.

Objective: In the past decade, there has been no systematic review of the evidence for maintenance of physical activity and/or dietary behavior change following intervention (follow-up). This systematic review addressed three questions: 1) How frequently do trials report on maintenance of behavior change? 2) How frequently do interventions achieve maintenance of behavior change? 3) What sample, methodologic, or intervention characteristics are common to trials achieving maintenance? Design: Systematic review of trials that evaluated a physical activity and/or dietary behavior change intervention among adults, with measurement at preintervention, postintervention, and at least 3 months following intervention completion (follow-up). Main Outcome Measures: Maintenance of behavior change was defined as a significant between-groups difference at postintervention and at follow-up, for one or more physical activity and/or dietary outcome. Results: Maintenance outcomes were reported in 35% of the 157 intervention trials initially considered for review. Of the 29 trials that met all inclusion criteria, 21 (72%) achieved maintenance. Characteristics common to trials achieving maintenance included those related to sample characteristics (targeting women), study methods (higher attrition and pretrial behavioral screening), and intervention characteristics (longer duration [>24 weeks], face-to-face contact, use of more intervention strategies [>6], and use of follow-up prompts). Conclusions: Maintenance of physical activity and dietary behavior change is not often reported; when it is, it is often achieved. To advance the evidence, the field needs consensus on reporting of maintenance outcomes, controlled evaluations of intervention strategies to promote maintenance, and more detailed reporting of interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sex differences in nicotine sensitization and conditioned hyperactivity in adolescent rats neonatally treated with quinpirole: Role of D2 and D3 receptor subtypes.

Neonatal quinpirole treatment in rats produces increased sensitivity of dopamine D2-like receptors throughout the animal’s lifetime, referred to as D2 priming. There is little information on the effects of nicotine in adolescent rats, especially in a model that has clinical relevance to psychosis where increased D2 receptor sensitivity is common. Male and female rats were treated with quinpirole (1 mg/kg) or saline from postnatal (P) day 1–P21, given nicotine (0.5 mg/kg) or saline from P33 through P49, and placed into a locomotor arena for behavioral testing. Nicotine or saline treatment was preceded by the D2-like receptor antagonist eticlopride, D3 antagonist nafadotride, or saline. Conditioned hyperactivity was analyzed on P50 in the same context in a drug-free test. In females, D2 priming increased the locomotor response to acute nicotine, but did not affect subsequent nicotine sensitization, and only non–D2-primed females demonstrated conditioned hyperactivity. Eticlopride and nafadotride blocked behavioral sensitization, although nafadotride was more effective at blocking nicotine-conditioned hyperactivity in females. In males, D? priming enhanced sensitization to nicotine and produced conditioned hyperactivity, which were blocked by eticlopride and nafadotride. These results have implications for psychosis and comorbidity of nicotine abuse in adolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The deterioration in physical function of hemodialysis patients

Introduction: Physical function in people on hemodialysis deteriorates significantly, however quantification of the rate of deterioration has not been well established. The aim of this study was to examine the rate of deterioration in objective physical function among end‐stage kidney disease patients receiving hemodialysis. Methods: One hundred and ninety‐three participants (mean age 67.5 ±13.2 years, 60.6% males) receiving hemodialysis in Australia. Objective physical function was assessed via the 30‐second sit‐to‐stand and eight‐foot timed up‐and‐go at baseline, 12 and 24 weeks. Findings: We found a decrease in the mean number 30‐second sit‐to‐stands performed from 10.0 (IQR, 4.0 to 13.0); 95% CI (8.0, 11.0) to 8.0 (IQR, 0.0 to 11.0); 95% CI (5.5, 9.0) at 12 weeks to 7.0 (IQR, 0.0 to 11.0); 95% CI (5.5, 9.0) at 24 weeks and a significant overall decreased rate (RR = 0.82; 95% CI, 0.80 to 0.85; P < 0.001). There was a decreased performance in the eight‐foot timed up‐and‐go time from 8.9 seconds (95% CI: 8.1 to 9.7) to 9.0 (95% CI: 8.1 to 9.7) after 12 weeks and further increasing to 9.7 (95% CI: 8.7 to 9.6) seconds after 24 weeks, and overall decreased rate (HR = 0.56; 95% CI, 0.39 to 0.80; P = 0.001) between baseline and week 24. Discussion: Physical function significantly decreases on hemodialysis. Exercise programs to address this physical function decline should be included in hemodialysis treatment regimens.     

Chemoenzymatic Isolation and Characterization of High Purity Mammalian Melanin

Although melanin is one of the most ubiquitous polymers in living systems, our understanding of its molecular structure, biosynthesis and biophysical properties has been limited to only a small number of organisms other than humans. This is in part due to the difficulty associated with isolating pure melanin. While purification methods exist, they typically involve harsh treatments with strong acid/base conditions combined with elevated temperatures that can lead to the polymer backbone degradation. To be successful, a viable isolation method must deliver a selective, yet complete degradation of non-melanin biopolymers as well as remove small molecule metabolites that are not integrative to the melanin backbone. Here, we demonstrate the use of chemoenzymatic processing guided by fluorescent probes for the purification and isolation of native mammalian melanin without significant induction of chemical degradation. This multi-step purification-tracking methodology enables quantitative isolation of pure melanin from mammalian tissue for spectroscopic characterization.