Nucleic acid-based approaches to investigate microbial-related cheese quality defects

peer-reviewedThe microbial profile of cheese is a primary determinant of cheese quality. Microorganisms can contribute to aroma and taste defects, form biogenic amines, cause gas and secondary fermentation defects, and can contribute to cheese pinking and mineral deposition issues. These defects may be as a result of seasonality and the variability in the composition of the milk supplied, variations in cheese processing parameters, as well as the nature and number of the non-starter microorganisms which come from the milk or other environmental sources. Such defects can be responsible for production and product recall costs and thus represent a significant economic burden for the dairy industry worldwide. Traditional non-molecular approaches are often considered biased and have inherently slow turnaround times. Molecular techniques can provide early and rapid detection of defects that result from the presence of specific spoilage microbes and, ultimately, assist in enhancing cheese quality and reducing costs. Here we review the DNA-based methods that are available to detect/quantify spoilage bacteria, and relevant metabolic pathways in cheeses and, in the process, highlight how these strategies can be employed to improve cheese quality and reduce the associated economic burden on cheese processors.This work was funded by the Department of Agriculture, Food and the Marine under the Food Institutional Research Measure. Daniel J. O’Sullivan is in receipt of a Teagasc Walsh Fellowship, Grant Number:2012205

Underwater Central California: A Guide to Saving Your Ocean Heritage

Describes the state of the wildlife and habitats inside the three national marine sanctuaries that stretch along the coast of central California, and identifies key threats to the future of California's coast

Temporal and spatial differences in microbial composition during the manufacture of a Continental-type cheese

peer-reviewedWe sought to determine if the time, within a production day, that a cheese is manufactured has an influence on the microbial community present within that cheese. To facilitate this, 16S rRNA amplicon sequencing was used to elucidate the microbial community dynamics of brine salted Continental-type cheese in cheeses produced early and late in the production day. Differences in microbial composition of the core and rind of the cheese were also investigated. Throughout ripening, it was apparent that late production day cheeses had a more diverse microbial population than their early day equivalents. Spatial variation between the cheese core and rind was also noted in that cheese rinds were found to initially have a more diverse microbial population but thereafter the opposite was the case. Interestingly, the genera Thermus, Pseudoalteromonas and Bifidobacterium, not routinely associated with a Continental-type cheese produced from pasteurised milk were detected. The significance, if any, of the presence of these genera will require further attention. Ultimately, the use of high throughput sequencing has facilitated a novel and detailed analysis of the temporal and spatial distribution of microbes in this complex cheese system and established that the period during a production cycle at which a cheese is manufactured can influence its microbial composition.This work was funded by the Department of Agriculture, Food and the Marine under the Food Institutional Research Measure through the ‘Cheeseboard 2015’ project. Daniel J. O’Sullivan is in receipt of a Teagasc Walsh Fellowship, Grant Number: 201220

High-throughput DNA sequencing to survey bacterial histidine and tyrosine decarboxylases in raw milk cheeses

peer-reviewedBackground The aim of this study was to employ high-throughput DNA sequencing to assess the incidence of bacteria with biogenic amine (BA; histamine and tyramine) producing potential from among 10 different cheeses varieties. To facilitate this, a diagnostic approach using degenerate PCR primer pairs that were previously designed to amplify segments of the histidine (hdc) and tyrosine (tdc) decarboxylase gene clusters were employed. In contrast to previous studies in which the decarboxylase genes of specific isolates were studied, in this instance amplifications were performed using total metagenomic DNA extracts. Results Amplicons were initially cloned to facilitate Sanger sequencing of individual gene fragments to ensure that a variety of hdc and tdc genes were present. Once this was established, high throughput DNA sequencing of these amplicons was performed to provide a more in-depth analysis of the histamine- and tyramine-producing bacteria present in the cheeses. High-throughput sequencing resulted in generation of a total of 1,563,764 sequencing reads and revealed that Lactobacillus curvatus, Enterococcus faecium and E. faecalis were the dominant species with tyramine producing potential, while Lb. buchneri was found to be the dominant species harbouring histaminogenic potential. Commonly used cheese starter bacteria, including Streptococcus thermophilus and Lb. delbreueckii, were also identified as having biogenic amine producing potential in the cheese studied. Molecular analysis of bacterial communities was then further complemented with HPLC quantification of histamine and tyramine in the sampled cheeses. Conclusions In this study, high-throughput DNA sequencing successfully identified populations capable of amine production in a variety of cheeses. This approach also gave an insight into the broader hdc and tdc complement within the various cheeses. This approach can be used to detect amine producing communities not only in food matrices but also in the production environment itself.This work was funded by the Department of Agriculture, Food and the Marine under the Food Institutional Research Measure through the ‘Cheeseboard 2015’ project. Daniel J. O’Sullivan is in receipt of a Teagasc Walsh Fellowship, Grant Number: 2012205

Yeast genomic expression patterns in response to low-shear modeled microgravity

The low-shear microgravity environment, modeled by rotating suspension culture bioreactors called high aspect ratio vessels (HARVs), allows investigation in ground-based studies of the effects of microgravity on eukaryotic cells and provides insights into the impact of space flight on cellular physiology. We have previously demonstrated that low-shear modeled microgravity (LSMMG) causes significant phenotypic changes of a select group of Saccharomyces cerevisiae genes associated with the establishment of cell polarity, bipolar budding, and cell separation. However, the mechanisms cells utilize to sense and respond to microgravity and the fundamental gene expression changes that occur are largely unknown. In this study, we examined the global transcriptional response of yeast cells grown under LSMMG conditions using DNA microarray analysis in order to determine if exposure to LSMMG results in changes in gene expression. LSMMG differentially changed the expression of a significant number of genes (1372) when yeast cells were cultured for either five generations or twenty-five generations in HARVs, as compared to cells grown under identical conditions in normal gravity. We identified genes in cell wall integrity signaling pathways containing MAP kinase cascades that may provide clues to novel physiological responses of eukaryotic cells to the external stress of a low-shear modeled microgravity environment. A comparison of the microgravity response to other environmental stress response (ESR) genes showed that 26% of the genes that respond significantly to LSMMG are involved in a general environmental stress response, while 74% of the genes may represent a unique transcriptional response to microgravity. In addition, we found changes in genes involved in budding, cell polarity establishment, and cell separation that validate our hypothesis that phenotypic changes observed in cells grown in microgravity are reflected in genome-wide changes. This study documents a considerable response to yeast cell growth in low-shear modeled microgravity that is evident, at least in part, by changes in gene expression. Notably, we identified genes that are involved in cell signaling pathways that allow cells to detect environmental changes, to respond within the cell, and to change accordingly, as well as genes of unknown function that may have a unique transcriptional response to microgravity. We also uncovered significant changes in the expression of many genes involved in cell polarization and bud formation that correlate well with the phenotypic effects observed in yeast cells when grown under similar conditions. These results are noteworthy as they have implications for human space flight

Occupational Therapy on College Campuses: Facilitating Student Success Through Occupation

Purpose: To explore how occupational therapy services fit into a supported education model on college campuses. Rationale: College students present with many strengths and challenges in college settings. There are limited services for young adults to succeed in college and students with various diagnoses face challenges in the areas of time management, organization, academic skills, and in social areas of college (Orentlicher, & Olson, 2010; Rogers, Kash-MacDonald, Bruker, & Maru, 2010). Higher education is a role emerging area for occupational therapists, and there are some pioneering occupational therapists who have discovered multiple ways to provide services to students who are challenged by aspects of college life. Objectives: Describe the history and current practice of supported education and its fit within the domain of OT. Describe a variety of OT supported education programmes Identify aspects of the supported education programmes that participants could apply to their college or practice setting Format: This workshop will begin by describing the history and models of supported education. The presenters will define six examples of OT programmes on college campuses. Finally, the presenters will encourage participants to share ideas and identify aspects of the various programs that they could apply to their college or practice setting

Shifting gears versus sudden stops: qualitative study of consultations about driving in patients with cognitive impairment

Objective General practitioners (GPs) report finding consultations on fitness to drive (FtD) in people with cognitive impairment difficult and potentially damaging to the physician–patient relationship. We aimed to explore GP and patient experiences to understand how the negative impacts associated with FtD consultations may be mitigated. Methods Individual qualitative interviews were conducted with GPs (n=12) and patients/carers (n=6) in Ireland. We recruited a maximum variation sample of GPs using criteria of length of time qualified, practice location and practice size. Patients with cognitive impairment were recruited via driving assessment services and participating general practices. Interviews were audio-recorded, transcribed and analysed thematically by the multidisciplinary research team using an approach informed by the framework method. Results The issue of FtD arose in consultations in two ways: introduced by GPs to proactively prepare patients for future driving cessation or by patients who urgently needed a medical report for an expiring driving license. The former strategy, implementable by GPs who had strong relational continuity with their patients, helped prevent crisis consultations from arising. The latter scenario became acrimonious if cognition had not been openly discussed with patients previously and was now potentially impacting on their right to drive. Patients called for greater clarity and empathy for the threat of driving cessation from their GPs. Conclusion GPs used their longitudinal relationship with cognitively impaired patients to reduce the potential for conflict in consultations on FtD. These efforts could be augmented by explicit discussion of cognitive impairment at an earlier stage for all affected patients. Patients would benefit from greater input into planning driving cessation and acknowledgement from their GPs of the impact this may have on their quality of life.Road Safety Authority of Irelan

Examining the transformation of midwifery education in Australia to inform future directions: an integrative review

BackgroundIntegral to quality midwifery practice is the education of midwives. Like other countries, Australia faces ongoing challenges in delivering midwifery education programs. Reasons include escalating program costs, challenges in securing meaningful clinical experiences, subsumption of midwifery with nursing, and associated loss of identity in some institutions.AimTo critically examine the literature exploring the historical and current drivers, supports and impediments for entry-to-practice midwifery programs to identify strategies to strengthen midwifery education in Australia.MethodsA structured integrative literature review using Whittemore and Knafl’s five-stage framework was undertaken; 1) problem identification, 2) literature search, 3) data evaluation, 4) data analysis, and 5) presentation of results.FindingsThe literature search identified 50 articles for inclusion. The thematic analysis identified four key themes: i. a commitment to educational reform, ii. building a midwifery workforce, iii. quality maternity care through midwifery education, and iv. progressing excellence in midwifery education.DiscussionExtensive literature describes the evolution of midwifery education in Australia over the last 30 years. Through collaboration and amidst opposition, quality midwifery education has been established in Australia. Identification of midwifery as a distinct profession and transformative leadership have been integral to this evolution and must be grown and sustained to prevent a decline in standards or quality.ConclusionThere is a need to address priorities in midwifery education and for the evaluation of midwifery programs and pedagogy. The provision and maintenance of quality education and practice require shared responsibility between education providers and health care services

Compromised Lactobacillus helveticus starter activity in the presence of facultative heterofermentative Lactobacillus casei DPC6987 results in atypical eye formation in Swiss-type cheese

peer-reviewedNonstarter lactic acid bacteria are commonly implicated in undesirable gas formation in several varieties, including Cheddar, Dutch-, and Swiss-type cheeses, primarily due to their ability to ferment a wide variety of substrates. This effect can be magnified due to factors that detrimentally affect the composition or activity of starter bacteria, resulting in the presence of greater than normal amounts of fermentable carbohydrates and citrate. The objective of this study was to determine the potential for a facultatively heterofermentative Lactobacillus (Lactobacillus casei DPC6987) isolated from a cheese plant environment to promote gas defects in the event of compromised starter activity. A Swiss-type cheese was manufactured, at pilot scale and in triplicate, containing a typical starter culture (Streptococcus thermophilus and Lactobacillus helveticus) together with propionic acid bacteria. Lactobacillus helveticus populations were omitted in certain vats to mimic starter failure. Lactobacillus casei DPC6987 was added to each experimental vat at 4 log cfu/g. Cheese compositional analysis and X-ray computed tomography revealed that the failure of starter bacteria, in this case L. helveticus, coupled with the presence of a faculatively heterofermentative Lactobacillus (L. casei) led to excessive eye formation during ripening. The availability of excess amounts of lactose, galactose, and citrate during the initial ripening stages likely provided the heterofermentative L. casei with sufficient substrates for gas formation. The accrual of these fermentable substrates was notable in cheeses lacking the L. helveticus starter population. The results of this study are commercially relevant, as they demonstrate the importance of viability of starter populations and the control of specific nonstarter lactic acid bacteria to ensure appropriate eye formation in Swiss-type cheese