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Brain-derived neurotrophic factor (BDNF) has a critical role in stress response including neuropsychiatric disorders that are precipitated by stress, such as major depressive disorder (MDD). BDNF acts through its full-length BDNF receptor tyrosine kinase B (TrkB) to trigger a pro-plasticity effect. In contrast, the truncated isoform of the BDNF receptor (TrkB.t1) triggers an anti-plasticity effect. In stress outcomes, BDNF acting in the hippocampus has a stress resilience effect, and, inversely, in the nucleus accumbens (NAc), BDNF acts as a stress susceptible molecule. It is unknown if BDNF-TrkB acts on a specific NAc projection neuron, i.e., medium spiny neuron (MSN or spiny projection neuron), a subtype in stress outcomes. To determine this, we performed chronic social or vicarious witness defeat stress (CSDS or CWDS) in mice expressing TrkB.t1 in dopamine receptor 1 or 2 containing MSNs (D1- or D2-MSNs). Our results showed that TrkB.t1 overexpression in NAc D2-MSNs prevented the CSDS-induced social avoidance or other stress susceptible behaviors in male and female mice. We further showed that this overexpression in D2-MSNs blocked stress susceptible behavior induced by intra-NAc BDNF infusion. In contrast, our results demonstrate that overexpression of TrkB.t1 on NAc D1-MSNs facilitates the SDS susceptible behaviors. Our study provides enhanced details into the NAc cell subtype role of BDNF-TrkB signaling in stress outcomes.

Sample preparation is a leading bottleneck in rapid detection of pathogenic bacteria. Here, we use Lyse-It® for bacterial cellular lysis, genomic DNA fragmentation, and protein release and degradation for both Listeria monocytogenes and Vibrio cholerae. The concept of Lyse-It® employs a conventional microwave and Lyse-It® slides for intensely focused microwave irradiation onto the sample. High microwave power and a

Pathogens that adapt to environmental stress can develop an increased tolerance to some physical or chemical antimicrobial treatments. The main objective of this study was to determine if acid adaptation increased the tolerance of Escherichia coli O157:H7 to high voltage atmospheric cold plasma (HVACP) in raw pineapple juice. Samples (10 mL) of juice were inoculated with non-acid-adapted (NAA) or acid-adapted (AA) E. coli to obtain a viable count of ~7.00 log10 CFU/mL. The samples were exposed to HVACP (70 kV) for 1–7 min, with inoculated non-HVACP-treated juice serving as a control. Juice samples were analyzed for survivors at 0.1 h and after 24 h of refrigeration (4 °C). Samples analyzed after 24 h exhibited significant decreases in viable NAA cells with sub-lethal injury detected in both NAA and AA survivors (p < 0.05). No NAA survivor in juice exposed to HVACP for 5 or 7 min was detected after 24 h. However, the number of AA survivors was 3.33 and 3.09 log10 CFU/mL in juice treated for 5 and 7 min, respectively (p < 0.05). These results indicate that acid adaptation increases the tolerance of E. coli to HVACP in pineapple juice. The potentially higher tolerance of AA E. coli O157:H7 to HVACP should be considered in developing safe juice processing parameters for this novel non-thermal technology.

As essential oils (EOs) possess GRAS status, there is a strong interest in their application to food preservation. Trends in the food industry suggest consumers are drawn to environmentally friendly alternatives and less synthetic chemical preservatives. Although the use of EOs has increased over the years, adverse effects have limited their use. This review aims to address the regulatory standards for EO usage in food, techniques for delivery of EOs, essential oils commonly used to control pathogens and molds, and advances with new active compounds that overcome sensory effects for meat products, fresh fruits and vegetables, fruit and vegetable juices, seafood, dairy products, and other products. This review will show adverse sensory effects can be overcome in various products by the use of edible coatings containing encapsulated EOs to facilitate the controlled release of EOs. Depending on the method of cooking, the food product has been shown to mask flavors associated with EOs. In addition, using active packaging materials can decrease the diffusion rate of the EOs, thus controlling undesirable flavor characteristics while still preserving or prolonging the shelf life of food. The use of encapsulation in packaging film can control the release of volatile or active ingredients. Further, use of EOs in the vapor phase allows for contact indirectly, and use of nanoemulsion, coating, and film wrap allows for the controlled release of the EOs. Research has also shown that combining EOs can prevent adverse sensory effects. Essential oils continue to serve as a very beneficial way of controlling undesirable microorganisms in food systems.

The US industrial revolution led to a significant increase in the amount of dietary sugar consumed annually. The impact has become a public health crisis over the past several decades. The consequences are seen in the dramatic rise in rates of obesity, type 2 diabetes mellitus, and cardiovascular disease.