Bioaccessibility and Cellular Uptake of Lutein, Zeaxanthin and Ferulic Acid from Muffins and Breads Made from Hairless Canary Seed, Wheat and Corn Blends.

Using a simulated gastrointestinal digestion model combined with a Caco-2 cell model, this study aims to assess the bioaccessibility and cellular uptake of dietary lutein, zeaxanthin, and ferulic acid from muffins and bread prepared from blends of hairless canary seed (HCS), wheat, and corn. Residual digestive enzymes damaged the Caco-2 monolayer and necessitated the requirements for the additional clean-up of the digesta. Several digesta cleanup treatments were examined, and the C18 column, along with AEBSF inhibitor, was selected as the most effective treatment. However, the cleanup treatment reduced lutein, zeaxanthin, and ferulic acid concentrations. The bioaccessibility of lutein from muffins was high at 92-94% (without clean-up) and 81-86% (with cleanup); however, the cellular uptake was low (7-9%). The bioaccessibility and cellular uptake (4-11%) of zeaxanthin were lower than lutein. Ferulic acid from muffins exhibited a wide range of bioaccessibility for non-cleanup (105-229%) and clean-up (53-133%) digesta samples; however, cellular uptake was very low (0.5-1.8%). Bread made from wheat/HCS had higher lutein bioaccessibility (47-80%) than the control bread (42%), with an apical cellular uptake ranging from 4.3 to 9.2%. Similar to muffins, the bioaccessibility of zeaxanthin from bread was lower than lutein, while ferulic acid had a fairly high bioaccessibility at 98-103% (without clean-up) and 81-102% (with cleanup); however, zeaxanthin cellular uptake was low (0.2%). These results suggest that muffins and bread could boost the daily consumption of lutein, zeaxanthin, and ferulic acid, allowing for a small portion to be absorbed in the small intestine.

Thoracic Surgery In-Training Exam Predicts Written But Not Oral Board Pass Rates: A 15-Year Single-Center Analysis.

The purpose of the Thoracic Surgery Director's Association In-Training Exam (ITE) is to gauge competency and progression of thoracic surgery residents and to prepare residents for the American Board of Thoracic Surgery (ABTS) examinations. We sought to identify the relationship between traditional resident ITE scores and success at passing the written or oral portion of the ABTS examinations. ITE and ABTS examination records from 2003 to 2019 were examined for all 2-year traditional cardiothoracic surgery residents at a single institution. Paired t tests were carried out between residents on their first- and second-year ITE. Bivariate logistic regression was performed on each of the second ITE component with written or oral board passing rate as the outcome of interest. Sixty residents completed training and took both written and oral boards. First attempt board pass rates were 90% for written and 75% for oral board examination. There was a significant improvement in test scores for each resident between the first the second ITE (P< 0.001 for all scores). Both increasing overall raw (odds ratio 1.26, P = 0.022) and scaled (odds ratio 1.08, P = 0.006) ITE scores were associated with passing the written boards on first attempt. There were no associations identified for oral board passing rates. Traditional residents improved ITE scores from first to second attempt. Increasing ITE scores were associated with improved written but not oral ABTS component pass rates. The ITE serves prepare residents for the ABTS qualifying (written) exam and assists programs with gauging resident readiness for taking this exam.

The effect of oxidative stress on gene expression of Shiga toxin-producing Escherichia coli (STEC) O157:H7 and non-O157 serotypes.

Understanding the survival mechanisms used by Shiga toxin-producing Escherichia coli (STEC), including O157:H7 and non-O157 serotypes, is important for minimizing contamination of fresh produce and occurrence of foodborne outbreaks. Recent outbreaks linked to leafy green vegetables and sprouted seeds have prompted researchers to focus on investigating decontamination strategies. Several studies showed that hydrogen peroxide (H2O2) treatment has been effective in reducing pathogens on fresh produce. As such, the effect of hydrogen peroxide on stress-associated and virulence gene expression in six STEC isolates was investigated in this study. Logarithmic phase cells of E. coli O157:H7 (EDL933) and non-O157 serotypes, including E. coli O26:H11 (EC20070549), O103:H2 (EC19970811), O104:H4 (NML#11-3088), O111:NM (EC20070546) and O145:NM (EC19970355) were exposed to 2.5mM H2O2 for 40 min and gene expression was evaluated using quantitative real-time PCR. Different patterns of gene expression were observed in E. coli O157:H7 and non-O157 serotypes. Particularly, Shiga toxin gene stx2 was upregulated in O157:H7, but not in O104:H4. Moreover, stx1 was significantly upregulated in STEC O157:H7, but only slightly upregulated Stx1-positive non-O157 serotypes. However genes related to motility (fliC) and intimin gene (eae) were downregulated in most strains. Stress-associated sodA gene encoding manganese superoxide dismutase was significantly upregulated in all serotypes. The dps gene coding for non-specific DNA binding protein was upregulated in O145:NM, O111:NM, O103:H2 and O26:H11. However genes related to cold shock (cspC) and acid resistance (gadW) were significantly downregulated in all strains tested. The results of this study provide a basic understanding of the oxidative stress impact on survival and virulence of non-O157 serotype STEC strains.

Lactic acid bacteria and bifidobacteria attenuate the proinflammatory response in intestinal epithelial cells induced by Salmonella enterica serovar Typhimurium.

Inflammation is a physiological response to infections and tissue injury; however, abnormal immune responses can give rise to chronic inflammation and contribute to disease progression. Various dietary components, including probiotic lactic acid bacteria and prebiotics, have the potential to modulate intestinal inflammatory responses. One factor in particular, the chemokine interleukin-8 (IL-8, CXCL-8), is one of the major mediators of the inflammatory response. The purpose of this study was to investigate modulation of the inflammatory host response induced by Salmonella enterica serovar Typhimurium DT104 in the presence of selected probiotics and lactic acid bacteria (LAB) isolated from human sources, dairy products, and farm animals. IL-8 gene expression and protein production in HT-29 cells were evaluated by real-time PCR and ELISA, respectively. Pre-incubation of HT-29 cells with Lactobacillus kefir IM002, Bifidobacterium adolescentis FRP 61, Bifidobacterium longum FRP 68 and FRP 69, Bifidobacterium breve FRP 334, and Leuconostoc mesenteroides IM080 significantly inhibited IL-8 secretion induced by Salmonella Typhimurium DT104. Co-culture of selected probiotics and Salmonella Typhimurium DT104 reduced IL-8 production, while potential probiotics and LAB had no effect on IL-8 secretion in HT-29 cells preincubated with Salmonella Typhimurium DT104 prior to adding probiotics. Lactobacillus kefir IM002 supernatant also significantly reduced IL-8 production. In conclusion, our study suggests that probiotic bifidobacteria and LAB modulate cytokine induction and possess anti-inflammatory properties; however, the effectiveness is strain dependent.

Allocation of scarce resources during mass casualty events.

OBJECTIVES: This systematic review sought to identify the best available evidence regarding strategies for allocating scarce resources during mass casualty events (MCEs). Specifically, the review addresses the following questions: (1) What strategies are available to policymakers to optimize the allocation of scarce resources during MCEs? (2) What strategies are available to providers to optimize the allocation of scarce resources during MCEs? (3) What are the public's key perceptions and concerns regarding the implementation of strategies to allocate scarce resources during MCEs? (4) What methods are available to engage providers in discussions regarding the development and implementation of strategies to allocate scarce resources during MCEs? DATA SOURCES: We searched Medline, Scopus, Embase, CINAHL (Cumulative Index to Nursing and Allied Health Literature), Global Health, Web of Science®, and the Cochrane Database of Systematic Reviews from 1990 through 2011. To identify relevant non-peer-reviewed reports, we searched the New York Academy of Medicine's Grey Literature Report. We also reviewed relevant State and Federal plans, peer-reviewed reports and papers by nongovernmental organizations, and consensus statements published by professional societies. We included both English- and foreign-language studies. REVIEW METHODS: Our review included studies that evaluated tested strategies in real-world MCEs as well as strategies tested in drills, exercises, or computer simulations, all of which included a comparison group. We reviewed separately studies that lacked a comparison group but nonetheless evaluated promising strategies. We also identified consensus recommendations developed by professional societies or government panels. We reviewed existing State plans to examine the current state of planning for scarce resource allocation during MCEs. Two investigators independently reviewed each article, abstracted data, and assessed study quality. RESULTS: We considered 5,716 reports for this comparative effectiveness review (CER); we ultimately included 170 in the review. Twenty-seven studies focus on strategies for policymakers. Among this group were studies that examined various ways to distribute biological countermeasures more efficiently during a bioterror attack or influenza pandemic. They provided modest evidence that the way these systems are organized influences the speed of distribution. The review includes 119 studies that address strategies for providers. A number of these studies provided evidence suggesting that commonly used triage systems do not perform consistently in actual MCEs. The number of high-quality studies addressing other specific strategies was insufficient to support firm conclusions about their effectiveness. Only 10 studies included strategies that consider the public's perspective. However, these studies were consistent in their findings. In particular, the public believes that resource allocation guidelines should be simple and consistent across health care facilities but should allow facilities some flexibility to make allocation decisions based on the specific demand and supply situation. The public also believes that a successful allocation system should balance the goals of ensuring the functioning of society, saving the greatest number of people, protecting the most vulnerable people, reducing deaths and hospitalizations, and treating people fairly and equitably. The remaining 14 studies provided strategies for engaging providers in discussions about allocating and managing scarce medical resources. These studies did not identify one engagement approach as clearly superior; however, they consistently noted the importance of a broad, inclusive, and systematic engagement process. CONCLUSIONS: Scientific research to identify the most effective adaptive strategies to implement during MCEs is an emerging area. While it remains unclear which of the many options available to policymakers and providers will be most effective, ongoing efforts to develop a focused, well-organized program of applied research should help to identify the optimal methods, techniques, and technologies to strengthen our nation's capacity to respond to MCEs.

Utilization of different types of dietary fibres by potential probiotics.

A better understanding of the functionality of probiotics and dietary fibres with prebiotic activity is required for the development of improved synbiotic preparations. In this study, utilization of ß(2-1) fructans, galactooligosaccharides, and plant polysaccharides as prebiotics by lactobacilli, bifidobacteria, and pediococci was investigated. Our results demonstrate that prebiotics with linear chains consisting of galactose units are better utilized by probiotics than are those consisting of glucose and fructose units, and the ability of probiotic bacteria to utilize prebiotics is strain-specific. In addition, rye fructooligosaccharides represent a prebiotic fibre that supports the growth of a wide range of probiotic cultures and as such has a potential to improve the successfulness of probiotic treatments. This study also demonstrates dietary fibre utilization by pediococci and provides data supporting the possible use of pediococci as a probiotic in synbiotic combinations.

Escherichia coli O157:H7 stress and virulence gene expression on Romaine lettuce using comparative real-time PCR.

Foodborne outbreaks attributed to the contamination of fresh produce with Escherichia coli O157:H7 are a growing concern. In particular, leafy-green vegetables, including lettuce and spinach, are susceptible to contamination by irrigation water, manure, and food processing and storage practices. The survival of E. coli O157:H7 and natural microflora on Romaine lettuce stored at 4 degrees C and 15 degrees C over a 9-day period was evaluated by plate counts. A two-step reverse-transcription comparative quantitative real-time PCR assay was employed to evaluate expression of genes coding for the A subunit of Shiga-toxin 1 and 2 (stx1A and stx2A), intimin (eaeA), flagellin (fliC), sigmaS--general stress sigma factor (rpoS) and iron superoxide dismutase (sodB) in E. coli O157:H7. Results indicate that reducing the storage temperature from 15 degrees C to 4 degrees C significantly (P<0.05) reduced the growth of Escherichia coli O157:H7 on Romaine lettuce, however, viable populations remained after the end of both storage periods. At end of the storage period, a 0.430 and 0.180 log decrease in E. coli O157:H7 was observed at 4 degrees C and 15 degrees C, respectively. Under both storage temperatures, total aerobic plate counts increased over the duration of the experiment. An increase in E. coli O157:H7 fold expression was observed with stx2A. Although stx1A exhibited upregulation for all storage conditions, variable gene expression was observed throughout the storage period. In addition, fliC was up-regulated during storage at 15 degrees C, while transcription at 4 degrees C storage changed only slightly. Expression of eaeA was variable at 15 degrees C with a tendency towards down-regulation, however, this gene was slightly up-regulated when stored at 4 degrees C. A slight upregulation of rpoS and sodB was also observed at 4 degrees C. In conclusion, our results suggest E. coli O157:H7 may become more virulent with prolonged storage of Romaine lettuce, particularly when stored at refrigerated temperatures.

The effect of probiotics and organic acids on Shiga-toxin 2 gene expression in enterohemorrhagic Escherichia coli O157:H7.

Probiotics are known to have an inhibitory effect against the growth of various foodborne pathogens, however, the specific role of probiotics in Shiga-toxin-producing Escherichia coli (STEC) virulence gene expression has not been well defined. Shiga toxins are members of a family of highly potent bacterial toxins and are the main virulence marker for STEC. Shiga toxins inhibit protein synthesis in eukaryotic cells and play a role in hemorrhagic colitis and hemolytic uremic syndrome. STEC possesses Shiga toxin 1 (Stx1) and Shiga toxin 2 (Stx2), both of which have A and B subunits. Although STEC containing both Stx1 and Stx2 has been isolated from patients with hemorrhagic colitis, Stx2 is more frequently associated with human disease complications. Thus, the effect of Lactobacillus, Pediococcus, and Bifidobacterium strains on stx2A expression levels in STEC was investigated. Lactic acid bacteria and bifidobacteria were isolated from farm animals, dairy, and human sources and included L. rhamnosus GG, L. curvatus, L. plantarum, L. jensenii, L. acidophilus, L. casei, L. reuteri, P. acidilactici, P. cerevisiae, P. pentosaceus, B. thermophilum, B. boum, B. suis and B. animalis. E. coli O157:H7 (EDL 933) was coincubated with sub-lethal concentrations of each probiotic strain. Following RNA extraction and cDNA synthesis, relative stx2A mRNA levels were determined according to a comparative critical threshold (Ct) real-time PCR. Data were normalized to the endogenous control glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and the level of stx2A expression between treated and untreated STEC was compared. Observed for all probiotic strains tested, stx2A was down-regulated, when compared to the control culture. Probiotic production of organic acids, as demonstrated by a decrease in pH, influenced stx2A gene expression.

Current and future uses of real-time polymerase chain reaction and microarrays in the study of intestinal microbiota, and probiotic use and effectiveness.

Probiotics are defined as live microorganisms that confer a health benefit to the host when administered in adequate amounts. In addition to human health benefits, probiotics can improve various aspects of growth and performance in livestock and poultry, as well as control undesirable microorganisms in food animals. Studies indicate that probiotics can prevent or treat certain conditions, including atopic disease in infants, food allergy, infection after surgery, acute diarrhea, and symptoms associated with irritable bowel syndrome. Understanding the complete mechanism, effectiveness, and potential use of probiotics is limited by the availability and sensitivity of current methods (i.e., culturing techniques). In recent years, real-time polymerase chain reaction (PCR) and microarrays have become prominent and promising methods to examine quantitative changes of specific members of the microbial community and the influence of probiotics on the structure and function of human and animal intestinal ecosystems. Culture-independent studies have established that only a fraction of organisms present in feces are cultivable, therefore, results obtained by cultivation are limited. Conversely, in-depth knowledge of microbial genomes has enabled real-time PCR and microarrays to be more sensitive and has resulted in precise methods for comprehensive analysis of the complex gut microbiota. Additionally, these technologies can assess the influence of intestinal microorganisms on host metabolism, nutrient status, and disease. This paper reviews method technologies and applications of real-time PCR and microarray assays as they relate to the effect and use of probiotics on the intestinal microbiota and gastrointestinal disease.

Comparison of most probable number-PCR and most probable number-foci detection method for quantifying infectious Cryptosporidium parvum oocysts in environmental samples.

Microbial contamination of public water supplies is of significant concern, as numerous outbreaks, including Cryptosporidium, have been reported worldwide. Detection and enumeration of Cryptosporidium parvum oocysts in water supplies is important for the prevention of future cryptosporidiosis outbreaks. In addition to not identifying the oocyst species, the U.S. EPA Method 1622 does not provide information on oocyst viability or infectivity. As such, current detection strategies have been coupled with in vitro culture methods to assess oocyst infectivity. In this study, a most probable number (MPN) method was coupled with PCR (MPN-PCR) to quantify the number of infectious oocysts recovered from seeded raw water concentrates. The frequency of positive MPN-PCR results decreased as the oocyst numbers decreased. Similar results were observed when MPN was coupled to the foci detection method (MPN-FDM), which was done for comparison. For both methods, infectious oocysts were not detected below 10(3) seeded oocysts and the MPN-PCR and MPN-FDM estimates for each seed dose were generally within one-log unit of directly enumerated foci of infection. MPN-PCR estimates were 0.25, 0.54, 0 and 0.66 log(10) units higher than MPN-FDM estimates for the positive control, 10(5), 10(4) and 10(3) seed doses, respectively. The results show the MPN-PCR was the better method for the detection of infectious C. parvum oocysts in environmental water samples.