Physicochemical And Toxicological Assessment Of Antimicrobial ε-Polylysine-Pectin Complexes

ε-Polylysine is an appealing FDA-approved, all natural antimicrobial biopolymer effective against a wide range of microorganisms. Its implementation is greatly limited by its strong cationic charge, which has been linked to instability in food systems, perceived astringency and bitterness, and the ability to inhibit lipid digestion. Previous studies have shown that controlled complexation of ε-polylysine with anionic pectin is able to prevent instability and astringency in simplified model food systems, while maintaining the antimicrobial character of polylysine. Isothermal titration calorimetry, micro-electrophoresis, microscopy, and turbidity analyses of the stability of electrostatic pectin-polylysine complexes in the presence of strongly anionic κ-carrageenan, and carrageenan-polylysine complexes in the presence of pectin at different mass ratios (pH 3.5) suggested that although polylysine-carrageenan interactions were much stronger, polylysine-pectin complexes maintained their stability in the presence of carrageenan. In vitro digestion models showed that electrostatic interactions between bile salts and polylysine, which have been suggested as the mechanism for lipase inhibition by polylysine (2ppm), were affected by components in the sample’s matrix. The implementation of an anionic (quillaja saponin) versus a non-ionic surfactant (Tween 20) in corn oil emulsions (2.5%w/w) showed a marked decrease of lipase inhibition, suggesting that electrostatic complexes formed by polylysine with other components prior to its exposure to bile salts in the small intestine may prevent the lipase-inhibiting polylysine-bile salts complex from occurring. Corn oil emulsions (2%w/w) stabilized by Tween 20 subjected to oral, gastric, and intestinal digestion in the presence and absence of mucin and polylysine (200ppm) demonstrated that polylysine forms electrostatic complexes with bile salt-stabilized mixed micelles, potentially decreasing lipid absorption and altering its metabolism. Complexes formed between polylysine and mucin prior to addition of bile salts showed a decrease in insolubilized oil after digestion, suggesting that interactions between polylysine and bile salts were somewhat inhibited. The influence of polylysine and pectin on the in vitro digestibility of animal feed either as individual components or as an electrostatic complex was assessed as part of a subchronic toxicity study. While pectin appeared to increase the rate and extent of lipid digestion, there did not seem to be any inhibition generated by polylysine

Variaciones del carpe diem y los conceptos de la vida y la muerte en el soneto “A una rosa”, de sor Juana Inés de la Cruz

This essay is a literary analysis of sor Juana Inés de la Cruz’s poem, “A una rosa.” sor Juana was, especially for her time period, a very influential and unique poet. The essay begins with a brief introduction of sor Juana, and then begins the analysis of the structure and figures of speech of “A una rosa.” The main topic of the essay is to examine the differing structures that sor Juana uses to demonstrate the concept of carpe diem and the similar structures she uses to establish her ideas of life and death as two things that are very similar, despite the fact that they are opposites. The research calls upon the works of literary analysts who have studied sor Juana’s use of these concepts and who have studied her different structures in depth. The essay also refers to other poems that sor Juana has written to demonstrate how her use of carpe diem is different in “A una rosa” than in her other poetry, and to show how her ideas of life and death in “A una rosa” are explained with structures similar to those of her other poems. The appendix includes a complete breakdown of the syllables and rhyme of “A una rosa.

Early Evidence for Using a Train-the-Trainer Program to Teach Debriefing for Meaningful Learning

Background Competent debriefers are essential to promote positive learner outcomes. While important, providing training to faculty may be difficult. The Train-The-Trainer (TTT) model is a successful approach for efficiently training large groups of individuals. Methods This study used a purposive, descriptive research design to test the feasibility and effectiveness of a TTT program for teaching debriefers how to implement and train others to use Debriefing for Meaningful Learning (DML). Results With training, assessment, and individualized feedback, trainers and trainees alike improved their ability to use DML, as well as self-assess their debriefing. Conclusion The TTT program was a successful, feasible, cost-effective way to provide DML training

Effects of volume training on strength and endurance of back muscles: a randomized controlled trial

CONTEXT: Strength/resistance training volume has historically been supported in the American College of Sports Medicine recommendations. However, for the back muscles, exercise prescription related to the number of sets, such as single vs. multiple, is not well established in the literature. OBJECTIVE: The purpose of this study was to compare the effects of two training volumes on strength and endurance of back extensor muscles in untrained young participants, with regard to a repeated measures design. DESIGN: Randomized controlled trial. SETTING: Laboratory of functional evaluation and human motor performance. PARTICIPANTS: Forty-four untrained young participants (mean age = 21 yrs) were randomized into three groups: single set (SSG, n = 14), multiple sets (MSG, n = 15), and untrained control (CG, n = 15). INTERVENTION: The SSG and MSG underwent a 10-wk progressive resistance training program (2 days·week-1) using a 45° Roman chair. MAIN OUTCOME MEASURES: Back maximal strength (dynamometer) and isometric and dynamic endurance (time-limit, trunk extension-flexion cycles, and electromyography muscle fatigue estimates). RESULTS: The results showed differences between the MSG and control group for isometric endurance time (mean 19.8 seconds, 95% CI 44.1 to 4.8), but without time intervention significance. Significant improvement after training (P 0.05) difference in either strength or electromyography estimates after training. CONCLUSIONS: Both multiple and single volume training were efficient in promoting better back endurance during dynamic performance based on mechanical variables (time and number of repetitions)

High Fat Diet Rich in Saturated Fatty Acids, but Not Monounsaturated Fatty Acids, Impairs Glycogen Preservation after Adiponectin Treatment

High fat diet (HFD) is associated with the progression of obesity, type 2 diabetes and diminished insulin sensitivity, which is characterized by a lower glucose uptake and glycogen synthesis capacity in skeletal muscle. Adiponectin (Ad), on the other hand, is a cytokine secreted by adipose tissue that promotes glucose uptake and fatty acid oxidation in skeletal muscle. PURPOSE: To determine the effects of Ad on skeletal muscle glycogen, GLUT 4, mitochondrial and lipid content in animals fed with a HFD but with alterations in dietary fatty acids (mixed fat western diet and predominately monounsaturated fatty acid). METHODS: Male Sprague Dawley rats were fed a Western-style (21% fat) HFD for 9 weeks to induce obesity, then, for 6 weeks, continued the mixed fat Western diet (WD) (9.8% saturated fat; 7.7% mono; 3.5% poly; n=8) or a HFD high in monounsaturated fatty acids (MUFA) (21% fat; 17.76% mono; 1.8% poly; n=8). A control group followed a 15-week standard Chow diet (CD) (4.8% fat; 0.74% saturated fat; 2% mono; 1.77% poly; n=9). Right and left hind-leg extensor digitorum longus (EDL) muscles were incubated in an organ bath (containing Krebs-Henseleit buffer with 2000 mg/L glucose, without calcium chloride and sodium bicarbonate) with or without 0.1 mg/ml Ad for 30 minutes. Glycogen content in the EDL muscle was measured by using periodic acid-schiff staining, while GLUT 4 protein content was measured using rabbit polyclonal antibody against GLUT 4 (ab654), mitochondrial content was measured using a mouse polyclonal antibody against COX 4 protein (ab14744) and lipid content was measured using BODIPY 493/503, using immunohistochemistry techniques. Images were quantified with ImageJ software. RESULTS: The Ad incubation resulted in a decrease in muscle glycogen content in animas fed with WD (4.85 ± 0.13 to 4.29 ± 0.11 AU; p=0.05). This decrease in glycogen content in the WD group was significantly different compared to a better preservation of glycogen in both CD (p=0.04) and the MUFA diet groups (p=0.012) (CD: 0.11 ± 0.071 AU; WD: -0.25 ± 0.14 AU; MUFA: 0.18 ± 0.05 AU; one way ANOVA, p=0.01). Animals fed with CD tended to have a better preservation of lipid content compared to animals fed with WD (p=0.07) and a diet high in MUFA (p=0.09) (CD: 25.93 ± 11.2 AU; WD: -21.09 ± 14.81 AU; MUFA: 25.97 ± 16.17 AU; one way ANOVA, p=0.06). There were no significant changes in GLUT 4 and mitochondrial content regardless of diet and adiponectin incubation. CONCLUSIONS: Animals fed with a western style HFD rich in saturated fat show an impaired response to adiponectin induced increase/preservation of glycogen in skeletal muscle compared to a chow diet, as well as a HFD rich in MUFA. Diets high in saturated fatty acids may have an impaired response to adiponectin treatment

Lower Skeletal Muscle Mitochondrial Content After a High Fat Diet Rich in Polyunsaturated Fatty Acids Compared to a High Fat Diet Rich in Monounsaturated Fatty Acids

High fat diet (HFD) has been associated with weight gain, insulin resistance, and type 2 diabetes. The composition of fatty acids in various diets (monounsaturated, polyunsaturated, saturated) influence levels of blood insulin, glucose, and the onset of metabolic and cardiovascular diseases. PURPOSE: Determine the effects of high fat diets with alterations in the major dietary fatty acid content (a mixed fat western diet, a polyunsaturated fatty acid diet or a monounsaturated fatty acid diet) on skeletal muscle glycogen, lipid, glucose transporter 4 (GLUT4), and mitochondrial content. METHODS: Male Sprague Dawley rats were fed a 21% (by weight; 41% total energy) high fat western-style diet for 9 weeks to induce obesity. They were then divided into 3 dietary groups that continued on a HFD for the next 6 weeks of 1) mixed fat western diet (WD) (9.8% saturated, 7.7% mono; 3.5% poly; n=9); 2) monounsaturated fat (MUFA) (2.8% saturated, 15.8% mono; 2.2% poly; n=9); or 3) polyunsaturated fat (PUFA) (3.0% saturated; 2.9%mono; 15.7% poly; n=8). A control group followed a 15-week low fat Chow diet (CD) (4.8% fat; 0.74% saturated fat; 2% mono; 1.77% poly; n=9). At the end of the dietary intervention, glycogen content was measured in extensor digitorum longus (EDL) with periodic acid-schiff staining. GLUT4 protein content was measured using rabbit polyclonal antibody against GLUT4 (ab654), mitochondrial content was measured using mouse polyclonal antibody against COX4 protein (ab14744), and lipid content was measured using BODIPY 493/503, using immunohistochemistry techniques. Images were captured by ZEN imaging software by ZEIS and data was analyzed with ImageJ. RESULTS: There were no significant differences in glycogen content after 6 weeks of HFD with different dietary fatty acid composition, compared to control chow diet. (AU± SEM; CD: 4.41±0.04, WD: 4.74± 0.13, MUFA: 4.54± 0.08, PUFA: 4.54± 0.11, one-way ANOVA p= 0.11). There were also no significant differences in GLUT4 protein content (AU± SEM; CD: 74.68± 5.91, WD: 64.42 ± 2.88, MUFA: 76.12± 6.51, PUFA: 62.83± 4.12; one-way ANOVA p= 0.17) and lipid content after a HFD differing in dietary fatty acids compared to a control chow diet. (AU± SEM; CD: 168± 19.28, WD: 141.3 ± 15.5, MUFA: 193.7 ± 15.3, PUFA: 152.1± 16,69; one-way ANOVA p=0.18). Mitochondria content was less in HFD rich in PUFA when compared to HFD rich in MUFA (CD; WD; AU± SEM; MUFA 60.33±7.31 vs. PUFA 37.42±5.53; MUFA vs. PUFA p= 0.03). CONCLUSION: Our data suggest that six weeks of high fat diet does not affect skeletal muscle glycogen content, lipid content and GLUT4 content regardless of dietary fatty acid composition. Six weeks of high fat diet rich in polyunsaturated fatty acids results in lower mitochondrial content compared to high fat diet rich in monounsaturated fatty acid. Our data suggest that high fat diet rich in polyunsaturated fatty acids may negatively impact skeletal muscle oxidative capacity compared to a diet rich in monounsaturated fatty acids

Food-grade cationic antimicrobial ε-polylysine transiently alters the gut microbial community and predicted metagenome function in CD-1 mice

Diet is an important factor influencing the composition and function of the gut microbiome, but the effect of antimicrobial agents present within foods is currently not understood. In this study, we investigated the effect of the food-grade cationic antimicrobial ε-polylysine on the gut microbiome structure and predicted metagenomic function in a mouse model. The relative abundances of predominant phyla and genera, as well as the overall community structure, were perturbed in response to the incorporation of dietary ε-polylysine. Unexpectedly, this modification to the gut microbiome was experienced transiently and resolved to the initial basal composition at the final sampling point. In addition, a differential non-random assembly was observed in the microbiomes characterized from male and female co-housed animals, although their perturbation trajectories in response to diet remain consistent. In conclusion, antimicrobial ε-polylysine incorporated into food systems transiently alters gut microbial communities in mice, as well as their predicted function. This indicates a dynamic but resilient microbiome that adapts to microbial-active dietary components

Constitutively Activated NLRP3 Inflammasome Causes Inflammation and Abnormal Skeletal Development in Mice

The NLRP3 inflammasome complex is responsible for maturation of the pro-inflammatory cytokine, IL-1β. Mutations in NLRP3 are responsible for the cryopyrinopathies, a spectrum of conditions including neonatal-onset multisystem inflammatory disease (NOMID). While excessive production of IL-1β and systemic inflammation are common to all cryopyrinopathy disorders, skeletal abnormalities, prominently in the knees, and low bone mass are unique features of patients with NOMID. To gain insights into the mechanisms underlying skeletal abnormalities in NOMID, we generated knock-in mice globally expressing the D301N NLRP3 mutation (ortholog of D303N in human NLRP3). NOMID mice exhibit neutrophilia in blood and many tissues, including knee joints, and high levels of serum inflammatory mediators. They also exhibit growth retardation and severe postnatal osteopenia stemming at least in part from abnormally accelerated bone resorption, attended by increased osteoclastogenesis. Histologic analysis of knee joints revealed abnormal growth plates, with loss of chondrocytes and growth arrest in the central region of the epiphyses. Most strikingly, a tissue “spike" was observed in the mid-region of the growth plate in the long bones of all NOMID mice that may be the precursor to more severe deformations analogous to those observed in NOMID patients. These findings provide direct evidence linking a NOMID-associated NLRP3-activating mutation to abnormalities of postnatal skeletal growth and bone remodeling

Expression of NF-κB p50 in Tumor Stroma Limits the Control of Tumors by Radiation Therapy

Radiation therapy aims to kill cancer cells with a minimum of normal tissue toxicity. Dying cancer cells have been proposed to be a source of tumor antigens and may release endogenous immune adjuvants into the tumor environment. For these reasons, radiation therapy may be an effective modality to initiate new anti-tumor adaptive immune responses that can target residual disease and distant metastases. However, tumors engender an environment dominated by M2 differentiated tumor macrophages that support tumor invasion, metastases and escape from immune control. In this study, we demonstrate that following radiation therapy of tumors in mice, there is an influx of tumor macrophages that ultimately polarize towards immune suppression. We demonstrate using in vitro models that this polarization is mediated by transcriptional regulation by NFκB p50, and that in mice lacking NFκB p50, radiation therapy is more effective. We propose that despite the opportunity for increased antigen-specific adaptive immune responses, the intrinsic processes of repair following radiation therapy may limit the ability to control residual disease