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To investigate influenza vaccination rates and perceptions underlying vaccine noncompliance. Participants: Participants included undergraduate students (N = 365) at a rural, medium-sized university...

Background Neuropathic pain patients have described experiencing unprovoked, intermittent pain attacks with shooting, stabbing, and burning qualities. Rodent models used in previous literature usually only involve acute exposure, and/or are unable to manipulate the stimulation intensity in vivo by the experimenter during an experiment. New method This paper describes a method to induce controllable pain behaviors in rodents using a wireless portable electronic device that can be manipulated within the course of an experiment. A stimulating electrode was implanted at the L5 spinal nerve location in Sprague-Dawley rats and our custom-built wireless stimulating device was attached to deliver variable stimulation in freely moving animals (50 Hz, 0.5 V; 100 Hz, 1 V). Results Implantation itself did not induce hypersensitivity as measured by the mechanical paw withdrawal threshold test. Observation of pain behaviors (paw elevation and licking) indicated that high stimulation intensity yielded a significant increase in pain behaviors. Even further, high intensity stimulation resulted in a behavioral “wind-up” of pain behaviors that persisted into the resting period when no stimulation was applied. Comparison with existing methods and conclusions This method can be used to study pain behaviors in a controllable way in freely moving rodents in comparison to existing models that are acute and/or are unable to manipulate the stimulation intensity in vivo.

Supplemental Digital Content is Available in the Text., We report a systematic review and meta-analysis of studies that assessed the antinociceptive efficacy of cannabinoids, cannabis-based medicines, and endocannabinoid system modulators on pain-associated behavioural outcomes in animal models of pathological or injury-related persistent pain. In April 2019, we systematically searched 3 online databases and used crowd science and machine learning to identify studies for inclusion. We calculated a standardised mean difference effect size for each comparison and performed a random-effects meta-analysis. We assessed the impact of study design characteristics and reporting of mitigations to reduce the risk of bias. We meta-analysed 374 studies in which 171 interventions were assessed for antinociceptive efficacy in rodent models of pathological or injury-related pain. Most experiments were conducted in male animals (86%). Antinociceptive efficacy was most frequently measured by attenuation of hypersensitivity to evoked limb withdrawal. Selective cannabinoid type 1, cannabinoid type 2, nonselective cannabinoid receptor agonists (including delta-9-tetrahydrocannabinol) and peroxisome proliferator-activated receptor-alpha agonists (predominantly palmitoylethanolamide) significantly attenuated pain-associated behaviours in a broad range of inflammatory and neuropathic pain models. Fatty acid amide hydrolase inhibitors, monoacylglycerol lipase inhibitors, and cannabidiol significantly attenuated pain-associated behaviours in neuropathic pain models but yielded mixed results in inflammatory pain models. The reporting of criteria to reduce the risk of bias was low; therefore, the studies have an unclear risk of bias. The value of future studies could be enhanced by improving the reporting of methodological criteria, the clinical relevance of the models, and behavioural assessments. Notwithstanding, the evidence supports the hypothesis of cannabinoid-induced analgesia.

Preclinical pain assessments can be criticized for failing to adequately characterize the human clinical pain experience. Although recent assessments have improved upon this shortcoming, there are still significant limitations. One concern is that current procedures fail to examine underlying motivational drives related to pain. Therefore, we used a novel approach-avoidance paradigm that allowed a rat to either satisfy hunger or avoid noxious stimulation to reveal prioritizing of motivational drives. The operant paradigm utilized a single lever that the animal pressed for appetitive reward (approach). The lever press was associated with mechanical stimulation of an inflamed paw induced by subcutaneous injection of carrageenan (avoidance). The results revealed that carrageenan-injected animals had a significant suppression of lever pressing and, in addition, had a longer latency to approach and press a lever for appetitive reward. The pattern of operant behavioral responses indicates that the motivation to avoid pain superseded the motivation to alleviate hunger. Utilization of approach-avoidance paradigms, such as this one, can allow researchers to unravel the complexities of the pain experience with the goal of enhancing translation to clinical efficacy.

Local field potentials (LFP) reflect the spatially weighted low-frequency activity nearest to a recording electrode. LFP recording is a window to a wide range of cellular activities and has gained increasing attention over recent years. We here review major conceptual issues related to LFP with the goal of creating a resource for non-experts considering implementing LFP into their research. We discuss the cellular activity that constitutes the local field potential; recording techniques, including recommendations and limitations; approaches to analysis of LFP data (with focus on power-banded analyses); and finally we discuss reports of the successful use of LFP in clinical applications.

A micro-flipped classroom combines the traditional lecture-based course and the flipped classroom for a blended mixture of the two pedagogical approaches. It allows the instructor time to lecture in class, while promoting more interactive discussions between the students. In this study, we compared the differences between a traditional lecture-based course and a micro-flipped course to see if there were differences in three exam grades and overall course grades. Exam specific analyses revealed that exams delivered in the early and mid-semester (Exams 1 and 2) resulted in slightly higher grades in the micro-flipped class group, and the statistically significant benefits of the micro-flipped course emerged during the third exam. We conclude that all increases in student performance are meaningful, and benefits of the micro-flipped classroom can be realized within the course of one semester.

The anterior cingulate cortex (ACC) has been extensively cited as a key area for processing pain affect. While local field potential (LFP) studies in other fields have yielded a great deal of information about neural oscillations, there is a poverty in the pain literature about the neural LFP profile related to pain, particularly in freely moving animals. In this study, we revealed the LFP profile in the ACC in freely moving rats during carrageenan inflammation. Mechanical allodynia was recorded before and after unilateral injection of carrageenan/saline in the left hindpaw. LFP activity in the ACC was recorded at baseline, after injection, and after injection with mechanical stimulation to the paw using a von Frey filament. This study uniquely reveals that carrageenan injection significantly recruited ACC LFP activity in delta, theta, and alpha bands (0-13Hz). Application of von Frey mechanical stimulation to the carrageenan-injected paw resulted in a significant increase in delta, theta, and alpha bands over and above what was recruited by carrageenan alone and further expanded the LFP range to additionally include beta activity (13-30Hz). Taken together, these data reveal significant changes in the lowest-frequency activities in the LFP range during painful inflammation, which merit attention. LFP is a powerful window to reveal wide-range, integrated synaptic processing by low-frequency cellular events during behavior. Information about LFP during pain broadens the scope of our understanding of pain mechanisms, our greatest resource for designing management approaches.

The ventral tegmental area (VTA) has been established as a critical nucleus for processing behavioral changes that occur during psychostimulant use. Although it is known that cocaine induced locomotor activity is initiated in the VTA, not much is known about the electrical activity in real time. The use of our custom-designed wireless module for recording local field potential (LFP) activity provides an opportunity to confirm and identify changes in neuronal activity within the VTA of freely moving rats. The purpose of this study was to investigate the changes in VTA LFP activity in real time that underlie cocaine induced changes in locomotor behavior. Recording electrodes were implanted in the VTA of rats. Locomotor behavior and LFP activity were simultaneously recorded at baseline, and after saline and cocaine injections. Results indicate that cocaine treatment caused increases in both locomotor behavior and LFP activity in the VTA. Specifically, LFP activity was highest during the first 30 min following the cocaine injection and was most robust in Delta and Theta frequency bands; indicating the role of low frequency VTA activity in the initiation of acute stimulant-induced locomotor behavior. Our results suggest that LFP recording in freely moving animals can be used in the future to provide valuable information pertaining to drug induced changes in neural activity.