Specific Salivary Neuropeptides Shift Synchronously during Acute Stress in Fire Recruits.

Once thought of as an immune-privileged site, we now know that the nervous system communicates in a bidirectional manner with the immune system via the neuroimmune axis. Neuropeptides constitute a component of this axis, playing critical roles in the brain and periphery. The function of salivary neuropeptides in the acute stress response is not well understood. The purpose of this study is to investigate salivary neuropeptide levels during acute stress. Salivary samples were collected from fire recruits engaged in a stress training exercise previously shown to induce acute stress, at three separate timepoints during the exercise and levels of oxytocin, neurotensin, Substance P, α-MSH, and ß-Endorphin were measured using the Human Neuropeptide 5-Plex Custom Assay Eve Technologies. All neuropeptides increased throughout the acute stress simulation and during the recovery phase. Exploratory factor analysis (EFA) identified one factor contributing to baseline values across five neuropeptides and Pairwise Pearson Correlation Coefficient analysis showed positive correlations >0.9 for almost all neuropeptide combinations at the pre-stress timepoint. Further analysis identified negative and positive correlations between past-life trauma and self-assessed hardiness, respectively. Calculated neuropeptide scores showed an overall positive correlation to self-assessed hardiness. Altogether, our results suggest that salivary neuropeptides increase synchronously during acute stress and higher levels correlate with an increase in self-assessed hardiness. Further study is required to determine if interventions designed to enhance neuropeptide activity can increase stress resilience, especially in high-stress occupations such as firefighting.

Time- and temperature-dependent postmortem ∆9-tetrahydrocannabinol concentration changes in rabbits following controlled inhaled cannabis administration.

ostmortem redistribution (PMR), a well-known phenomenon in forensic toxicology, can result in substantial changes in drug concentrations after death, depending on the chemical characteristics of the drug, blood collection site, storage conditions of the body and postmortem interval (PMI). Limited PMR data are available for ∆9-tetrahydrocannabinol (THC), the primary psychoactive component in Cannabis sativa. PMR was evaluated after controlled cannabis inhalation via a smoking machine and exposure chamber in New Zealand white rabbits. Necropsies were performed on five control rabbits immediately after euthanasia, whereas 27 others were stored at room temperature (21°C) or refrigerated conditions (4°C) until necropsy at 2, 6, 16, 24 or 36 h after death. THC and its Phase I and glucuronidated Phase II metabolites were quantified in blood, vitreous humor, urine, bile and tissues by liquid chromatography-tandem mass spectrometry (LC-MS-MS). Under refrigerated temperature, heart blood THC concentrations significantly increased at PMI 2 h in rabbits, whereas peripheral blood THC concentrations showed a significant increase at PMI 16 h. Central:peripheral blood and liver:peripheral blood ratios for THC ranged from 0.13 to 4.1 and 0.28 to 8.9, respectively. Lung revealed the highest THC concentrations, while brain and liver exhibited the most stable THC concentrations over time. This report contributes much needed data to our understanding of postmortem THC behavior and can aid toxicologists in the interpretation of THC concentrations in medicolegal death investigations.

Impact of the USMLE Step 1 and COMLEX Level 1 transition to Pass/Fail on osteopathic medical student stress levels and board preparation.

CONTEXT: The United States Medical Licensing Examination (USMLE) Step 1 and Comprehensive Osteopathic Medical Licensing Exam (COMLEX) Level 1 transitioned from a numeric scoring system to a Pass/Fail designation in 2022. This transition intended to decrease stress, improve medical student well-being, and encourage residency program directors to emphasize other aspects of residency applications. Pass/Fail score transitions in the undergraduate medical education curriculum have improved medical student psychological well-being and satisfaction; whether these same benefits translate to the board examination period is unknown. OBJECTIVES: The objectives of this study are to assess the impact of USMLE Step 1 and COMLEX Level 1 grade scale transition on medical student stress, wellness, board preparation decisions, and future residency selection processes. Investigators hypothesized that students under the Pass/Fail designation would experience less stress during the intensive study period leading up to USMLE Step 1 and COMLEX Level 1 and devote more time to other aspects of their residency applications. METHODS: To examine the impact on osteopathic medical student (OMS) stress and approach to board preparation, two surveys were administered to Rocky Vista University College of Osteopathic Medicine (RVU-COM) students before (Class of 2023) and after (Class of 2024) the transition to a Pass/Fail designation. All students within the RVU-COM Classes of 2023 and 2024 were invited to participate. The Cohen Perceived Stress Scale (PSS-10) was administered at the beginning of the focused board study period in May 2021 and 2022 to the Class of 2023 and 2024, respectively. The investigator-designed Licensing Exam Questionnaire (LEQ), meant to capture board preparation patterns, residency application perspectives, and wellness during examination preparation, was administered immediately after the board examination deadline in July 2021 and 2022 to the Class of 2023 and 2024, respectively. Statistical analysis included the use of independent t tests (numeric variables) and chi-square tests (categorical data). This project was considered exempt from full Institutional Review Board review. RESULTS: Approximately one-third of the Class of 2023 (PSS-10: n=86; LEQ: n=93) and 2024 (PSS-10=89; LEQ: n=92) responded. No difference was detected in mean PSS-10 score, 20.14 (SD=7.3) compared to 19.92 (SD=6.56) for the Class of 2023 and 2024 (p=0.84), respectively. The Class of 2023 reported more weeks studying (mean 6.27 weeks, SD=0.79) vs. the Class of 2024 (mean 5.44 weeks, SD=0.007), p<0.001, more practice examinations taken X 2 (1, n=182)=13.75, p<0.001, and a greater proportion scheduled examinations after June 20 X 2 (1, n=182)=29.01, p<0.001. No difference existed in hours studying per day, sequence of Step 1/Level 1, time between examinations, money spent, or type of study resources utilized. CONCLUSIONS: The transition of USMLE Step 1 and COMLEX Level 1 to a Pass/Fail designation did not reduce stress for OMSs at a single, multicampus COM. Respondents, however, altered board preparation practices in meaningful ways. As student behaviors and board-study patterns emerge, these insights must be connected to outcomes in the future.

Cytokine fluctuation during acute stress is correlated to life trauma.

BACKGROUND: Multiple studies have demonstrated that human neurobiology and behavior are inextricably linked to the activity of our immune systems. Trauma is associated with a multitude of immune system changes; reflecting this, posttraumatic stress disorder (PTSD) is often comorbid with immune-related conditions such as autoimmune disorders. To further investigate this phenomenon, we tested our hypothesis that cytokine fluctuations during and after an acute stress response correlates with experienced life trauma. METHODS: Using a prospective observational approach, this cohort study measured biomarker profiles in firefighter participants (n = 63), with 9 participants having prior PTSD diagnoses and 54 without prior PTSD diagnoses. In addition, life trauma scores were determined from all participants using the Life Events Checklist 5 (LEC-5) survey. Baseline salivary biomarker concentrations were determined, along with levels immediately before, immediately after, and 1 hour following a standardized stressful training event. Biomarkers measured using these salivary samples included 42 cytokines and 6 steroid and thyroid hormones. The concentrations of these markers were then correlated, using Pearson correlation coefficients, with the participants' LEC-5 scores. t Tests were also performed to compare cytokine values between the populations with and without prior PTSD diagnosis. RESULTS: Included in the cytokine panel were interleukin (IL)-8, IL-10, IL-1B, GCSF, IL1-Ra, Groα, IFNa2, PDGFAA, and VEGF, all of which demonstrated positive correlation at various time points in individuals with increased severity of LEC-5 scores (and thus increased experienced life trauma). Concentrations of Groα, PDGFAA, IL1-Ra, IL-1a, Mip1a, IL-1a, IL-6, Mip1b, TNFα, and TGFα were also found to be significantly altered at various time points in participants with prior PTSD diagnoses, demonstrating some overlap with the LEC-5 Pearson correlations. CONCLUSION: The results support our hypothesis and demonstrate that LEC-5 scores are indeed significantly correlated to cytokine concentrations and fluctuations surrounding a stress test. LEVEL OF EVIDENCE: Diagnostic Tests or Criteria; Level IV.

Impact of COVID-19 on Rocky Vista University medical students' mental health: A cross-sectional survey.

Background: The COVID-19 pandemic brought immense changes to medical school curriculums world-wide, such as the widespread adoption of virtual learning. We sought to better understand the impact on medical students' mental health at Rocky Vista University College of Osteopathic Medicine, Parker, CO, United States. This study assessed the impact the pandemic had on anxiety and depression levels of medical students. It also assessed the impact of several domains on student mental health during the pandemic and how various sub-groups within the studied population were affected. Methods: A cross-sectional survey was sent to students through an online anonymous google survey in May to June 2021, centered around the 7-item questionnaire used to screen for Generalized Anxiety Disorder GAD-7, 9-item questionnaire used to screen for depression PHQ-9, and self-designed questions to assess the personal impact of the pandemic. Data obtained were screened for error and analyzed with significance value of p < 0.05. Results: A total of 152 responses were received (25.5% response rate). Of these, 64.1% identified as female, 75.8% were white, 50.3% were between ages 21-25, and 77.8% were first year medical students. During the pandemic, 79.6% of respondents felt more anxious and 65.1% felt more depressed. 67.8% of students reported feeling social isolation amidst the pandemic. Students living with friends were more likely to see a therapist for depression during the pandemic (p = 0.0169) and prescribed an antidepressant (p = 0.0394). Females and students in relationships were more likely to score higher on GAD-7 (p = 0.0194) and (p = 0.0244), respectively. Conclusion: This study investigated the effect of the pandemic on medical students' mental health and the need to address this issue. Results suggest that the pandemic had a negative impact on medical student's mental health and that anxiety and depression levels worsened for pre-clinical medical students at Rocky Vista University. As such, it is imperative to incorporate additional resources to protect the well-being of medical students as they progress through their medical careers.

Principal component analysis of salivary cytokines and hormones in the acute stress response.

The acute stress response is characterized by activation of multiple interconnected systems in the body, resulting in the release of a flood of hormones and immune mediators into circulation. In addition to detection of these molecules in the serum, saliva can serve as a source of these markers as well and can be collected in a non-invasive way. The complete profile of salivary biomarkers associated with the hypothalamic pituitary adrenal/gonadal axes and the immune system during the acute stress response has not been fully elucidated. In a cohort of 62 first responders engaged in a stress training exercise, we set out to determine patterns of cytokine, chemokine and hormone shifts during the acute stress response. Salivary samples were collected immediately before (pre-stress), immediately after (post-stress) and 1 h after the stress test (recovery). Multiplex ELISA panels of 42 cytokines and 6 steroid and thyroid hormones were used to determine concentrations of these biomarkers during the three aforementioned time points. Principal components analysis was conducted to determine patterns in the large data sets collected. In our ≥0.3 loading principal components analysis, for pre-stress vs. post, post-stress vs. recovery and pre-stress vs. recovery, a total of three, four and three factors accounted for 56.6, 68.34, and 61.70% of the biomarker variation for each phase respectively. In the ≥0.7 loading principal components analysis, three, four and three factors were found for pre-stress vs. post, post-stress vs. recovery and pre-stress vs. recovery stages, respectively. Of note, in our ≥0.3 loading principal components analysis, MCP1 was present in all three factors from pre-stress to post-stress, and fractalkine was found to be in all four factors post-stress vs. recovery and pre vs. recovery from stress. Additionally, hormones testosterone, estradiol, T4 and T3 grouped together consistently in the same factor for all phases of acute stress in both ≥0.3 and ≥0.7 principal components analysis. Overall, our results identified specific patterns of immune markers and hormones that shift during acute stress and warrant further investigation to understand their mechanistic role in regulating the stress response.

Dried Plum's Polyphenolic Compounds and Carbohydrates Contribute to Its Osteoprotective Effects and Exhibit Prebiotic Activity in Estrogen Deficient C57BL/6 Mice.

Evidence of dried plum's benefits on bone continues to emerge. This study investigated the contribution of the fruit's polyphenol (PP) and carbohydrate (CHO) components on a bone model of postmenopausal osteoporosis to explore their prebiotic activity. Osteopenic ovariectomized mice were fed diets supplemented with dried plum, a crude extract of dried plum's polyphenolic compounds, or the PP or CHO fraction of the crude extract. The effects of treatments on the bone phenotype were assessed at 5 and 10 weeks as well as the prebiotic activity of the different components of dried plum. Both the CHO and PP fractions of the extract contributed to the effects on bone with the CHO suppressing bone formation and resorption, and the PP temporally down-regulating formation. The PP and CHO components also altered the gut microbiota and cecal short chain fatty acids. These findings demonstrate that the CHO as well as the PP components of dried plum have potential prebiotic activity, but they have differential roles in mediating the alterations in bone formation and resorption that protect bone in estrogen deficiency.

In vitro effect of hydroxyethyl starch on coagulation in dogs as assessed by dynamic viscoelastic coagulometry.

OBJECTIVE: To evaluate the effect of 6% hydroxyethyl starch (HES) 670/0.75 and 6% HES 130/0.4 dilution of canine whole blood on coagulation using dynamic viscoelastic coagulometry (DVC). ANIMALS: 56 healthy adult dogs. PROCEDURES: 2 blood samples were obtained from each dog and randomized to 1 of 7 groups-undiluted or 2 dilutions (1:3 or 1:10) of 3 different fluids: saline (0.9% NaCl) solution, 6% HES 670/0.75, or 6% HES 130/0.4. Dilutions were calculated to simulate approximately a 10- or 30-mL/kg body weight IV bolus of each fluid. DVC was performed on each sample. Coagulation parameters compared between groups included clot rate (CR), platelet function (PF), and activated clotting time. RESULTS: Dilution with saline solution did not significantly affect coagulation, while dilution with HES 670/0.75 and HES 130/0.4 caused a dose-dependent significant decrease in CR (1:3 HES 670/0.75, P = 0.007; 1:10 HES 670/0.75, P = 0.002; 1:3 HES130/0.4, P < 0.0001; and 1:10 HES 130/0.4, P = 0.0003) and PF (1:3 HES 670/0.75, P < 0.0001; 1:10 HES 670/0.75, P < 0.0001; 1:3 HES130/0.4, P < 0.0001; and 1:10 HES 130/0.4, P = 0.0015). CLINICAL RELEVANCE: Dilution of canine blood with HES 670/0.75 and HES 130/0.4, at clinically relevant doses (10 and 30 mL/kg), led to significant hypocoagulability beyond dilutional effect. This was, in part, due to impaired PF, which was significantly greater with HES 670/0.75. Further research using DVC to assess the effects of HES on coagulation in dogs, ideally with clinical conditions warranting HES administration, is needed.

Comparative Histopathology of Bovine Acute Interstitial Pneumonia and Bovine Respiratory Syncytial Virus-Associated Interstitial Pneumonia.

Acute interstitial pneumonia (AIP) is a significant disease of cattle and many aetiologies have been implicated on the basis of the characteristic pathological lesions. Bovine respiratory syncytial virus (BRSV) is one of the key aetiological factors in bovine respiratory disease complex and several studies have suggested, controversially, that BRSV may be an underlying cause of bovine AIP. BRSV infection is known to cause several distinctive histopathological changes, including epithelial syncytia formation and intracytoplasmic viral inclusions. However, distinguishing bovine AIP from BRSV-related pneumonia by clinical presentation, gross pathology or histopathology can sometimes be challenging. In order to identify the potential distinguishing features, we compared the histopathological findings of AIP that were, and were not, associated with BRSV infection in naturally occurring cases. We found that multinucleated giant cells were more frequently identified in cattle with AIP while bronchiolitis was more common in BRSV-infected cattle. However, this was not considered a sole indicator of either disease group. Statistically, we identified that a combination of several histopathological features, including alveolar septal necrosis, presence of multinucleated giant cells and bronchiolitis, can serve as an excellent indicator for distinguishing between idiopathic AIP and BRSV-related pneumonia, with a strong statistical significance (P = 0.0004). Based on the results of this retrospective study, we present a histopathological scoring system for predicting BRSV-associated AIP.

Evaluation of the intervertebral disk, vertebral body, and spinal cord for changes secondary to percutaneous laser disk ablation.

OBJECTIVE: To evaluate the intervertebral disk, vertebral endplates, and spinal cord for perioperative changes secondary to percutaneous laser disk ablation (PLDA) and correlate findings to clinical outcomes in dogs receiving thoracolumbar PLDA. STUDY DESIGN: Blinded study. ANIMALS: Thirty dogs. METHODS: Magnetic resonance imaging (MRI) was performed before PLDA (control/Group C), immediately following PLDA (Group I), and 3 months later (perioperative/Group P). Dogs were followed 3 years. Groups and dogs were randomized for evaluation. Two radiologists were blinded to each MRI study and dog. Each radiologist evaluated the disk, vertebral body, and spinal cord at each disk space receiving PLDA. RESULTS: Mean disk degeneration was increased in Group P at L1-2 (p < .0001) and L2-3 (p = .0081). Both radiologists identified mild diskitis (1%-15%) in Group P (radiologist 1, p < .0001; radiologist 2, p = .0012). Cranial endplate lesions were identified in Group P at T11-12 (p = .0353), T13-L1 (p = .0026), and L4-5 (p = .0210). Lesions were identified in the caudal endplates of all eight disk spaces in Group P: T10-11 (p = .0004), T11-12 (p < .0001), T12-13 (p < .0001), T13-L1 (p < .0001), L1-2 (p < .0001), L2-3 (p < .0001), L3-4 (p < .0001), and L4-5 (p < .0001). There was no disk extrusion or spinal cord lesions identified. CONCLUSION: This study evaluated effects that may occur secondary to PLDA, using MRI. Although vertebral body changes were identified, they did not correlate with clinical complications. CLINICAL SIGNIFICANCE: PLDA appears to be a safe, effective procedure performed on thoracolumbar disks to reduce recurrence of intervertebral disk herniation (IVDH) in dogs that previously experienced IVDH, despite the appearance of visible vertebral endplate lesions and mild diskitis on MRI.

Effect of Bidirectional Insertion of External Skeletal Fixation Pins on Axial Pullout Strength in Canine Cadaveric Bone.

OBJECTIVE: The aim of this study was to evaluate the effect of bidirectional insertion on axial pullout strength of tapered run out (TRO), traditional negative profile (TNP) and positive profile (PP) pins. STUDY DESIGN: Cadaveric adult canine tibiae were harvested. Tapered run out pins (Group 1) were inserted unidirectionally to the desired position; bidirectionally past the desired position, then withdrawn to the desired position (Group 2); and bidirectionally as described for Group 2, repeated twice (Group 3). Traditional negative profile pins (Group 4-6) and PP pins (Group 9-11) were placed in the same manner. Tapered run out (Group 7), TNP (Group 8) and PP pins (Group 12) were driven unidirectionally such that the shaft of the pin violated the cis-cortex. A servohydraulic testing machine extracted the pins and measured axial peak pullout strength. RESULTS: Positive profile pins had significantly greater pullout strength than TRO and TNP pins placed unidirectionally to the desired position. Method of insertion had no effect on peak pullout strength of TNP pins. TRO and PP pins inserted unidirectionally to the desired position had significantly greater peak pullout strengths than insertion bidirectionally or if the shaft of the pin violated the cis-cortex. CONCLUSION: The authors recommend that pins used for external skeletal fixation should be placed unidirectionally to the desired position with fluoroscopic guidance, intra-operative depth gauge measurements or measurements from preoperative radiographs. Repositioning pins results in loss of peak pullout strength with TRO and PP pins.

Effects of 12 Months Consumption of 100 g Dried Plum (Prunes) on Bone Biomarkers, Density, and Strength in Men.

Several male animal studies have demonstrated bone-protective effects of dried plum; however, no human male study has evaluated the effect of dried plum on bone health. We conducted a randomized controlled clinical study to test if daily inclusion of 100 g of dried plum in the diet positively influenced bone mineral density (BMD), bone strength, and bone biomarkers in men. Sixty-six men were randomly assigned to one of two daily treatment groups: (1) control (0 g dried plum) or (2) 100 g dried plum. Blood samples were collected at baseline and after 3, 6, and 12 months to assess bone biomarkers. Bone was measured at baseline and after 6 and 12 months via dual-energy X-ray absorptiometry and peripheral quantitative computed tomography. Tartrate-resistant acid phosphatase-5b (TRAP5b) and C-terminal collagen cross-link (CTX) levels decreased significantly in the dried plum group at 3-, 6-, and 12-month intervals compared with baseline. No changes were observed in the control group for TRAP5b and CTX levels. Bone-specific alkaline phosphatase levels decreased significantly after 6 and 12 months in the control and dried plum groups. BMD for total body, spine (L1-L4), hip, and ulna did not change in the control and dried plum groups from baseline to 6 or 12 months. In the proximal tibia, endosteal circumferences increased significantly within the dried plum group during the course of treatment. The results suggest that daily consumption of 100 g dried plum for 12 months has modest bone-protective effects in men. ClinicalTrials.gov identifier: NCT04720833.

Isolate Virulence and Cultivar Response in the Winter Wheat: Pyrenophora tritici-repentis (Tan Spot) Pathosystem in Oklahoma.

Prevalence of tan spot of wheat caused by the fungus Pyrenophora tritici-repentis has become more prevalent in Oklahoma as no-till cultivation in wheat has increased. Hence, developing wheat varieties resistant to tan spot has been emphasized, and selecting pathogen isolates to screen for resistance to this disease is critical. Twelve isolates of P. tritici-repentis were used to inoculate 11 wheat cultivars in a greenhouse study in splitplot experiments. Virulence of isolates and cultivar resistance were measured in percent leaf area infection for all possible isolate x cultivar interactions. Isolates differed significantly (P < 0.01) in virulence on wheat cultivars, and cultivars differed significantly in disease reaction to isolates. Increased virulence of isolates detected increased variability in cultivar response (percent leaf area infection) (r = 0.56, P < 0.05) while increased susceptibility in cultivars detected increased variance in virulence of the isolates (r = 0.76, P < 0.01). A significant isolate × cultivar interaction indicated specificity between isolates and cultivars, however, cluster analysis indicated low to moderate physiological specialization. Similarity in wheat cultivars in response to pathogen isolates also was determined by cluster analysis. The use of diverse isolates of the fungus would facilitate evaluation of resistance in wheat cultivars to tan spot.

Influence of Temperature and Photoperiod on the Fecundity of Habrobracon hebetor Say (Hymenoptera: Braconidae) and on the Paralysis of Host Larvae, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae).

Studies were carried out in the laboratory to understand the optimum environmental conditions at which the ectoparasitoid, Habrobracon hebetor Say (Hymenoptera: Braconidae), can paralyze and lay eggs when reared on the larvae of the stored product pest, Plodia interpunctella Hübner (Lepidoptera: Pyralidae). At the four temperatures investigated (20, 25, 30, and 35 °C), optimum temperatures for oviposition were found to be 25 and 30 °C, while 35 °C was the least favorable temperature. No significant differences were found between the percentages of diapausing and non-diapausing larvae paralyzed by the wasp at the temperatures of 20, 25, 30, 35 °C within 5 days. However, in another experiment that investigated the effect of photoperiods at different temperatures that included 15, 19 and 28 °C, the number of paralyzed larvae was highly reduced at low temperatures (15 °C) but photoperiods had no significant impact on the number of host larvae paralyzed. In addition, observations at short time intervals also showed that lower temperatures slowed down host larvae paralysis. The results suggest that H. hebetor can paralyze host larvae of P. interpunctella more efficiently and deposit more eggs at temperatures within the range of 20-30 °C.

Development of methodology and reference intervals for the analysis of the free-ranging Atlantic horseshoe crab Limulus polyphemus hemolymph.

BACKGROUND: The Atlantic horseshoe crab, Limulus polyphemus, is valuable to fishing and biomedical industries, for education in public aquaria, and of ecological importance because the eggs provide a critical food source for migratory shorebirds. While hematologic and biochemical analyses are fundamental tools for health assessment, reports are limited for the four extant species of horseshoe crabs; L polyphemus (East Coast North America), Carcinoscorpius rotundicauda (mangrove horseshoe crab Southeast Asia), Tachypleus gigas, and Tachypleus tridentatus (Southeast and East Asia). OBJECTIVES: This prospective study measured hemolymph values to determine RIs from free-ranging horseshoe crabs during the annual breeding aggregation in Delaware Bay, USA. METHODS: Near-shore animals were briefly manually restrained for hemolymph collection from the cardiac sinus. Hematologic samples (25 males, 25 females) were collected for hemocytometer counts using the Natt and Herrick method. A second set of 50 animals (25 males, 25 females) was sampled for biochemistry measurands, including copper concentration by spectrophotometer, osmolality by vapor pressure osmometer, and protein electrophoresis. RESULTS: Total hemocyte counts varied widely (RI 6600-44 300/µL). Electrolytes were consistent with osmoconformers living in seawater. There was a marked difference in sexes, with females showing much lower protein, glucose, and copper levels. Eleven females had multiple outliers, and all data were excluded from RI calculations. CONCLUSIONS: Further studies of this species outside of spawning season are needed. Expanding our knowledge of horseshoe crab health is important to decreasing morbidity and mortality in research applications and maximizing longevity and overall health in display settings.

Trapping Tribolium castaneum (Coleoptera: Tenebrionidae) and Other Beetles in Flourmills: Evaluating Fumigation Efficacy and Estimating Population Density.

This paper reports beetle pests common to flourmills targeted during a series of trapping studies over a two-year period in flourmill 1 and a one year period in flourmill 2. Objectives were (1) use pheromone-baited traps to detect T. castaneum (Herbst) and other pest species present for their distribution over space and time, (2) monitor T. castaneum activity before and after fumigations to assess efficacy of the treatment, and (3) correlate counts of T. castaneum via trap capture against direct T. castaneum counts from samples of the milled flour to assess the value of trap data to estimate relative size of the pest population. Traps were deployed in two different flourmills over two consecutive years. T. castaneum was the most commonly trapped beetle during both years in mill 1. In mill 2, Typhaea stercorea (L.) and Cryptolestes ferrugineus (Stephens) were both captured in higher numbers than T. castaneum. In mill 1, trap capture was higher overall during Year 2 for most of the species compared with capture during Year 1, likely due to a dust cover modification made for the pitfall trap used in Year 2. Trap capture was also evaluated by location within the mills and a significant difference was found in the capture of T. stercorea during both years in mill 1. T. castaneum captures were significantly reduced following most fumigations, which used methyl bromide in milling areas and phosphine in bulk-stored finished flour. However, in most cases trap catches showed that beetle populations were not eliminated. Trap captures after fumigation suggest either that the fumigations were not entirely effective, or that full grown adult beetles were entering the mill soon after fumigation. When captures of T. castaneum from traps in two spaces of mill 1 during Year 2 were compared with counts of beetles from samples of siftings collected in the finished flour, the correlation coefficients were nearly significant for both sets of traps.

Early prediction of the risk of scoring lower than 500 on the COMLEX 1.

BACKGROUND: The Comprehensive Osteopathic Medical Licensing Examination of the United States Level 1 (COMLEX 1) is important for medical students to be able to graduate. There is a glaring need to identify students who are at a significant risk of performing poorly on COMLEX 1 as early as possible so that extra assistance can be provided to those students. Our goal is to produce a reliable predictive model to identify students who are at risk of scoring lower than 500 on COMLEX 1 at the earliest possible time. METHODS: Academic data from medical students who matriculated at Rocky Vista University College of Osteopathic Medicine between 2011 and 2017 were obtained. Odds ratios were used to assess the predictors for scoring lower than 500 on COMLEX 1. Correlation with COMLEX 1 scores was assessed with Pearson correlation coefficient. The predictive models were developed by multiple logistic regression, backward logistic regression, and logistic regression with average scores in courses in the first three semesters, and were based on performances on the Medical College Admissions Test (MCAT) before admission, as well as students' performances in preclinical courses during the first three semesters. The models were generated in about 82% of the student performance data and were then validated in the remaining 18% of the data. RESULTS: Odds ratios showed that MCAT scores and final grades in each course in the first three semesters were significant in predicting a score lower than 500 on COMLEX 1. Performances in third-semester courses including Renal System II, Cardiovascular System II, and Respiratory System II were most important in prediction. The three predictive models had sensitivities of 65.8 -71%, and specificities of 83.2 - 88.2% in predicting a score lower than 500 on COMLEX 1. CONCLUSIONS: Lower MCAT scores and lower grades in the first three semesters of medical school predict scoring lower than 500 on COMLEX 1. Students who are identified at risk by our models will have a 65.8 -71% chance of actually scoring lower than 500 on COMLEX 1. Those students will have enough time to receive assistance before taking COMLEX 1.

Safety and efficacy of cold atmospheric plasma for the sterilization of a Pasteurella multocida-contaminated subcutaneously implanted foreign body in rabbits.

OBJECTIVE: To determine whether a stainless steel implant sterilized with a novel cold atmospheric plasma sterilization (CAPS) device adversely affects local tissues in rabbits and whether CAPS was as effective as steam sterilization with an autoclave to inactivate Pasteurella multocida. ANIMALS: 31 healthy New Zealand White rabbits. PROCEDURES: Steam-autoclaved stainless steel implants inoculated with P multocida underwent a second steam autoclave sterilization (AIA) or CAPS (AICAPS). One AIA implant and 3 AICAPS implants were randomly placed subcutaneously at 4 sites in 21 rabbits (84 implants). These rabbits were monitored daily for 5 days for evidence of systemic illness and local tissue reactions at the implantation sites and then euthanized. Samples were taken from each implant site for bacterial culture and histologic examination. RESULTS: Cultures of samples obtained from all sites were negative for bacterial growth. No significant difference was observed in mean skin thickness or erythema between AIA and AICAPS implant sites on any observed day. Also, individual histologic grades for the epidermis, dermis, subcutis, and muscle and total histologic grade were not significantly different between AIA and AICAPS implant sites. CONCLUSIONS AND CLINICAL RELEVANCE: Cold atmospheric plasma sterilization was noninferior to steam sterilization of P multocida-contaminated stainless steel implants in the rabbits in the present study. However, studies of the efficacy of CAPS for inactivation of other important bacteria are needed.

The effect of environmental conditions on the rate of RNA degradation in dried blood stains.

The relationship between RNA degradation and the age of a bloodstain has been suggested by the work of several investigators. A prior study from this laboratory described a qPCR assay that was effective at estimating the age of bloodstains stored in an environmentally controlled laboratory for periods of up to one year. In this study, the effect of the environmental conditions on the rate of RNA degradation during storage was analyzed. Bloodstains were prepared on stain cards and stored in one of 9 different environments for periods of up to 24 weeks. At selected times during the storage term, RNA was extracted, reverse transcribed, and the integrity of select transcripts analyzed. Three temperatures (37 °C, 20 °C, and 4 °C) and three relative humidities (rH) (75 %, 35 %, and 10 %) were combined pairwise. The rate of RNA degradation was found to increase 5-10 fold in stains stored at 37 °C versus those stored at 20 °C. The rate of RNA degradation was faster for stains stored at 20 °C compared to 4 °C but differed only 2-4 fold. Multivariate regression analysis suggests elevations in temperature or rH will accelerate RNA degradation and will do so to a similar extent. It is clear from the data that the integrity of the transcriptome in dried bloodstains is better preserved in a cold and dry environment. Investigations are ongoing to develop an approach for the estimation of sample age that incorporates the environmental conditions of a crime scene into the age estimate.

Evaluation of Two-Leaf Sampling Units to Estimate Sugarcane Aphid (Hemiptera: Aphididae) Economic Thresholds in Commercial Grain Sorghum.

Sugarcane aphid Melanaphis sacchari Zehntner is a significant economic pest of grain sorghum in the United States. Effective monitoring and early detection are cornerstones for managing invasive pests. The recently developed binomial sequential sampling plan estimates sugarcane aphid economic thresholds (ETs) based on classification whether a 2-leaf sample unit has ≤ or ≥ 50 M. sacchari. In this study, we evaluated eight 2-leaf sampling units for potential use in the sequential sampling plan. From 2016 through 2017, whole plant counts of M. sacchari were recorded non-destructively in situ on sorghum plants from 140 fields located in five states. Plant canopies were stratified into three categories. Two leaves from each stratum were used to compare linear relationships between M. sacchari numbers per two-leaf sample unit and total M. sacchari density per plant. Analysis revealed that two randomly selected leaves from the middle stratum accounted more variation for estimating M. sacchari density when compared to two leaves from the other strata. Comparison of eight two-leaf sampling units within plant growth stages were variable in quantifying variation of M. sacchari densities. When growth stages were combined, the standard uppermost + lowermost leaf sample unit and a unit consisting of two randomly selected leaves from the middle stratum revealed little difference in their enumeration of variation in M. sacchari density. Because other sample units were either less predictive and/or more variable in estimating M. sacchari density, we suggest that the (L1+U1) sample unit remain the preferred method for appraising M. sacchari ETs.