bluuebunny/crossref_metadata_2025_split huggingface dataset:
A toolbox of strategies to improve test-taking skills: A comparison of student perceptions in physiology coursework
Authors: Metz Cynthia , Metz Cynthia , Metz Michael 
Published: May 2023

Recent changes in the Medical and Dental National Board Examination structures have renewed interest in the development of test-taking strategies for professional students. It is often assumed that these students have developed proficient test-taking skills and metacognitive abilities prior to admittance. However, the assessments in these programs and for national licensure require a high level of reasoning and integration that may necessitate additional training.The goal of this project was to present a toolbox of strategies that provided opportunities to: contemplate new test-taking strategies, observe modeling of appropriate skills, participate in formative and team-based activities to practice skills, and reflect on the use of the strategies following summative course assessments. It was hypothesized that the implementation of the immersive test-taking strategies program would improve student perceptions of their abilities and confidence regarding national board preparation.Dental students engage in physiology coursework in the first two semesters of the curriculum, which likely serves as a crucial time for the refinement of appropriate test-taking strategies. For this study, a “toolbox” of four methods was implemented with 120 students enrolled in a first-year Dental Physiology course. These included: 1. An introductory video that provided students with ten tips for approaching high-level exam questions 2. Problem solution videos interspersed with class practice problems to walk students through rationales 3. Collaborative group assessments in which students implemented the strategies in teams to prepare for exams and 4. Unit exam debriefings to review the question rationales.While all methods were positively reviewed on surveys, students indicated that the problem solution videos and the collaborative group assessments were more helpful and improved their test-taking skills significantly more than the other strategies (P<0.05, one-way ANOVA and Bonferroni post hoc test). On average, students rated their test-taking skills when entering the program at a 3.71 on a 5-point Likert scale. At the conclusion of the semester, they indicated that they had developed strong test-taking strategies for the course (average of 4.21) and felt more prepared to complete the National Board Dental Examination (average of 4.48)These results suggest that a multi-pronged approach, with frequent opportunities to practice test-taking strategies, can improve student perceptions of their ability to master high-level and integrated questions. Future studies will examine correlations between student perceptions and actual exam performance, and differences between medical and dental student populations. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Automation of the neonate autoresuscitation assay and its analysis
Authors: Ward Christopher , Patel Dipak , Ruiz Brandon , Garcia Acosta Mariana , Memos Nicoletta , Lusk Savannah , Aissi Eunice , Ray Russell 
Published: May 2023

Background: Sudden Infant Death Syndrome is thought to partly result from unseen brain abnormalities affecting cardio-respiratory function, but for which no clear genetic or environmental mechanisms are known. Mouse genetic and exposure models present an opportunity to uncover molecular and environmental mechanisms. However, measuring cardio-respiratory function in neonate mice is expensive, difficult, and inefficient. One major challenge is the time needed to carry out such measurements. The neonate autoresuscitation assay, consisting of repeated anoxic exposures followed by recovery, requires the full attention of an observer for the multi-hour duration of a single-subject assay, limiting throughput. To address this, we developed a closed-loop feature detection platform for automated neonate cardio-respiratory measurements. Methods: Our platform design consists of: 1) a pneumotachograph face-mask for precise respiratory measurements. 2) a micro-controller automated bell-housing gas switching system for rapid induction of respiratory challenges. 3) a micro-computer-based data-acquisition system with real-time feature detection and outputs for controlling gas exposure. 4) a data analysis suite that assists with recordkeeping and provides a facile method to extract key outcome measures. Results: Gas challenges are administered via the rotating bell housing system. A python program detects waveform features in real-time, such as apnea and bradycardia. Upon apnea detection, the system switches to a rescue gas. Resumption of normal breathing and heart rate can also be detected and incorporated into criteria for automated initiation of the next anoxic exposure trial. Data is stored for later offline automated analysis using the data analysis suite. Conclusions: The system offers a relatively inexpensive approach for automated high throughput neonate cardio-respiratory assessment. The improvements permitting increased throughput and reduced variation in experimental parameters makes the system suitable for screening of genetic and exposure risks as well as potential therapeutics for Sudden Infant Death Syndrome. NIH: R01 HL130249, UM1HG006348, R01DK114356. BCM KOMP2 Precision Disease Modeling Pilot Award, BCM McNair Scholar Program, March of Dimes Basil O’Connor Research Award, Parker B. Francis Fellowship, CJ Foundation for SIDS This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Chronic hyperoxia augments the hypoxic ventilatory response in adult rats
Authors: Danielson Matthew , Bavis Ryan 
Published: May 2023

Chronic hyperoxia during postnatal development causes long-lasting attenuation of the hypoxic ventilatory response (HVR) in rats, but similar exposures during adulthood do not attenuate the HVR (Ling et al. J Physiol 405: 561-571, 1996). However, the HVR has not been assessed in adult-exposed rats immediately after chronic hyperoxia (i.e., without several months of recovery in room air). This is important since chronic hyperoxia depresses breathing and blunts the HVR in newborn rats, and only some of these effects persist after return to room air. Accordingly, adult rats were studied after 4 and 14 days of exposure to either 60% O2 (Hyperoxia) or 21% O2 (Control). Ventilation was measured by whole-body plethysmography; metabolic O2 consumption and CO2 production were also measured in a subset of rats. Normoxic ventilation was unchanged, but Hyperoxia rats exhibited a slight increase in their acute HVR after both durations of chronic hyperoxia. Overall, minute ventilation was approximately 10% greater in Hyperoxia rats while breathing 12% O2 and 10% O2 than in Control rats; this effect did not differ significantly between female and male rats. The HVR was also enhanced after 4 days of hyperoxia after controlling for metabolic rate, but the results were less clear after 14 days. After the 14-day exposure, the HVR tended to be enhanced when tested at 12% O2 but not at 10% O2. These data demonstrate that chronic hyperoxia has different effects on the control of breathing in neonatal and adult rats when assessed immediately after the exposure. Supported by NIH grant P20 GM-103423 (Maine INBRE). This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Angiotensin II type 2 receptor-mediated dilation is greater in the cutaneous microvasculature of premenopausal women compared to men
Authors: Schwartz Kelsey , Lang James , Stanhewicz Anna 
Published: May 2023

Sex differences in the activation of the renin-angiotensin system (RAS) likely contribute to differences in cardiovascular outcomes in premenopausal women compared to age-matched men. It is established that women have a reduced activation of the vasoconstrictor angiotensin II – angiotensin II type 1 receptor (AT1R) pathway. Emerging evidence suggests that this may be mediated by a shift toward the more recently described vasodilatory RAS, including increased sensitivity of the vasodilatory angiotensin II type 2 receptor (AT2R). However, few in vivo studies have directly examined sex differences in AT2R-mediated dilation, or the balance between AT1R- and AT2R-mediated vascular responses in humans. Using the cutaneous microcirculation as a model, we hypothesized that AT2R-mediated dilation would be greater in premenopausal women compared to men, and that AT1R-blockade would augment AT2R-mediated dilation to a greater extent in men than in women. Eight healthy women (22±3 years) and 11 healthy men (23±5 years) participated in 1 experimental visit. Two intradermal microdialysis fibers were placed in the skin of the ventral forearm for graded infusions of either compound 21 (C21, AT2R agonist; 10-12 - 10-3 mol/L) alone or C21 + 43 μmol/L losartan (AT1R antagonist). Red blood cell flux was measured over each microdialysis site by laser-Doppler flowmetry. Cutaneous vascular conductance was calculated (CVC=doppler flux/mean arterial pressure) and normalized to maximum (%CVCmax; 28mM SNP+43°C). Women had a greater peak vasodilation response to C21 compared to men (27.2±5.7 versus 18.2±2.7 %CVCmax; p=0.03). AT1R-inhibition augmented peak C21-mediated dilation in men (31.3±4.5 versus 18.2±2.7 %CVCmax; p=0.009) but had no effect in women (24.5±6.5 versus 27.2±5.7 %CVCmax; p=0.34). These data suggest that premenopausal women have a greater AT2R-mediated vasodilation response than men, and that AT1R activation inhibits AT2R-mediated dilation in men, but not in women. This study is supported by National Heart, Lung, and Blood Institute Grant R00HL138133. Clinicaltrials.gov identifier: NCT05576155 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Microvascular Health is Reduced in Frequent Cannabis Users
Authors: Simovic Tijana , Mattheson Chloe , Cobb Kolton , Heefner Allison , Thode Christopher , Garten Ryan , Rodriguez-Miguelez Paula 
Published: May 2023

BACKGROUND: Microvascular dysfunction is a marker of endothelial vascular damage and is considered one of the earliest indicators of cardiovascular disease (CVD) development. Frequent cannabis use has been previously linked to increased CVD risk. However, whether microvascular health is impacted by cannabis use in otherwise healthy young adults has not been explored yet. PURPOSE: The purpose of this study was to investigate the impact of frequent cannabis usage on microvascular health in young healthy adults. METHODS: Thirteen frequent cannabis users (CU, 5 males and 8 females; age:23±3 yo; used cannabis 2.5±2 days/week) and thirteen demographical matched never users (NU, 5 males and 8 females; age:22±1 yo) completed a comprehensive assessment of microvascular function. Microvascular health was assessed using Laser Doppler Imaging coupled with Post Occlusive Reactive Hyperemia (PORH), to evaluate overall microvascular function, and Local Thermal Hyperemia (LTH) to evaluate neurogenic and endothelial mechanisms of vascular function. Blood flow was calculated as cutaneous vascular conductance, considering red blood cell flux and mean arterial blood pressure. RESULTS: Cannabis users exhibited significantly ( p=0.01) lower microvascular function when compared to never users (PORH, CU: 0.68±0.18 vs. NU: 0.85±0.14 mmHg/PU). Of note, microvascular function was significantly ( p=0.03) reduced in those that use cannabis more than 2.5 days/week (n=5; 0.55±0.10) when compared to those who used it less frequently (n=8; 0.76±0.18 mmHg/PU). In addition, neurogenic mechanisms (CU:1.31±0.57 vs. NU: 1.89±0.48 mmHg/PU; p=0.009) and endothelial mechanisms (CU: 1.61±0.44 vs. NU: 1.96±0.35 mmHg/PU; p=0.03) were significantly lower in cannabis users when compared to never users. CONCLUSIONS: Our results suggest that frequent cannabis users exhibit reduced microvascular health in comparison to never users, suggesting worse long-term CVD outcomes. Specifically, those that use cannabis more than 2 times per week exhibit lower microvascular function. In addition, cannabis use negatively impact neurogenic and endothelial microvascular mechanisms that warrant further investigation. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Nicotinamide adenine dinucleotide concentrations in a mouse model of Down Syndrome
Authors: Cooke Lauren , DeRuisseau Lara , Brandauer Josef 
Published: May 2023

Individuals with Down Syndrome (DS) may experience impaired cardiac and skeletal muscle function, resulting in lower work and exercise capacity, lower blood pressure, and reduced cardiovascular responses.Nicotinamide adenine dinucleotide (NAD) is critical for maintaining mitochondrial function. It transfers electrons within cells, acting as a messenger between metabolism and cell signals. It is uncertain whether DS pathophysiology is caused by an imbalance of NAD and/or changes in mitochondrial activity. Our study analyzed the levels of NAD in the tissue of wild-type and Ts65Dn (a mouse model of DS) mice. We hypothesized that NAD levels are differentially regulated in WT and Ts65Dn mouse tissue.NAD concentration was analyzed using a kinematic fluorescence assay. We normalized NAD concentration based on the tissue mass of each aliquot and corrected for between-plate differences using internal control samples. We found significantly different NAD concentrations in the left ventricle of Ts65Dn mice (WT, 22.8±5.1 mmol/mg, TS65 Dn, 15.3±4.1 mmol/mg [mean±SD], p=0.003), and non-significant but reduced concentrations in skeletal muscle (quadriceps, tibialis anterior), and kidney tissues of Ts65Dn animals. Our findings suggest that, based on our findings in a mouse model of DS, reduced NAD levels may be a part of the pathophysiology associated with DS. Characterizing this phenotype could lead to a better understanding of potential drug targets to alleviate the impaired cardiac and skeletal muscle function of DS, allowing for improved work and exercise capacity. This work was supported by a Gettysburg College Professional Development Grant to JB. LD was supported by NIH grants 1R15 HD076379, 3R15 HD076379-S1, 3R15 HD076379-S2, and 1R21HD099573. Further funding was provided by the Cross-disciplinary science institute at Gettysburg College via the Dickson Fund; Kolbe Fund; Albaugh Fund in Chemistry; Alberte Fund in Biology; and the Cormack, Hendrickson, Peterson and Schweizer Funds in Physics. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Hypocapnia increases heart rate in patients with Postural Orthostatic Tachycardia Syndrome (POTS)
Authors: Ranada Shaun , Karalasingham Kavithra , Baker Jacquie , Hira Rashmin , Wilson Richard , Phillips Aaron , Sheldon Robert , Raj Satish 
Published: May 2023

Background: Postural Orthostatic Tachycardia Syndrome (POTS) is characterized by chronic orthostatic intolerance and significantly impacts quality of life of patients. POTS predominantly affects women of child-bearing age with an estimated prevalence of up to 1%. POTS is defined by an excessive increase in heart rate (HR) of ≥30 bpm within 10 minutes of upright posture, in the absence of orthostatic hypotension. POTS is associated with chronic symptoms (≥6 months) including hyperventilation (HV) in the form of hyperpnea. HV reduces arterial CO2 (hypocapnia) and worsens tachycardia in POTS. Whether it is hypocapnia that increases HR in these patients is unclear. Studies have not investigated the effects of CO2 on HR due to the confounding effects of posture and ventilation. Objective: We aimed to determine if hypocapnia exacerbates tachycardia in POTS patients. Hypothesis: We hypothesize that hypocapnia will increase HR in POTS. Methods: We conducted a randomized crossover trial of hypocapnic HV vs. eucapnic HV in 13 female POTS patients (34±9 y). Participants completed the supine breathing protocol: 1) HV with resultant hypocapnia, and 2) HV (with end-tidal CO2 (ETCO2) clamped at baseline). Breath-by-breath respiratory (ventilation (VE), tidal volume (VT), ETCO2, end-tidal O2 (ETO2)) and beat-to-beat hemodynamics (HR, stroke volume (SV), cardiac output (CO)) were measured. Data are reported as mean±SD. Paired t-tests were used to compare respiratory and hemodynamic parameters between hypocapnic HV vs. eucapnic HV. Results: During HV, ETCO2 was significantly lower during hypocapnia vs. eucapnia (19.6±3.7 mmHg vs. 37.4±3.5 mmHg; p<0.0001). ETO2 was greater during hypocapnia vs eucapnia (117.4±4.7 mmHg vs. 114.6±3.1 mmHg; p<0.001). There was no difference in VE (22.2±6.5 L/min vs. 22.0±5.1 L/min; p=0.8) or VT (1.4±0.4 L vs. 1.4±0.3 L; p=0.9) between hypocapnia and eucapnia. HR was significantly greater during hypocapnia vs. eucapnia (99±12 bpm vs 82±10 bpm; p<0.001); SV was significantly lower during hypocapnia vs. eucapnia (66±14 mL vs. 74±13 mL; p=0.02); and there was no difference in CO between hypocapnia and eucapnia (6.4±1.3 L/min vs. 6.1±1.6 L/min; p=0.3). Conclusion: Independent of ventilation, hypocapnia increases HR in patients with POTS. Our findings suggests that hypocapnia causes a reduction in SV, perhaps due to increased blood pooling in the capacitance vessels leading to reduced venous return. This work was supported by Standing up to POTS. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Fentanyl induced disruption of the coordinated reciprocal activity of inspiratory and expiratory respiratory muscles
Authors: Grams Kirstyn , Neumueller Suzanne , Forster Hubert , Buiter Nicole , Hilbert Grace , Pan Lawrence , Lewis Stephen , Hodges Matthew 
Published: May 2023

Opioid induced respiratory depression (OIRD) occurs when respiratory pump and/or airway muscle activity are reduced ostensibly due to reduced output from the brainstem respiratory control system, resulting in central (CA) and/or obstructive apnea (OA) and reduced breathing frequency. Although less commonly reported in the literature, ORID may also result from an inappropriate activation of accessory muscles leading to the “Wooden Chest Syndrome” (WCS) -when airflow is limited due to simultaneous activation of inspiratory and expiratory pump and/or airway respiratory muscles to decrease chest wall compliance and inappropriately increase airway resistance. This phenomenon is difficult to directly study in humans, but here we present data from our large animal model (adult female goats). We tested the hypothesis that IV fentanyl would lead to transient dysfunction in respiratory accessory muscles indicative of WCS. We surgically instrumented goats (n=7) with electromyographic (EMG) wires in inspiratory (diaphragm; DIA) and expiratory (Transversus Abdominus; TA) pump muscles, as well as airway dilator (Thyropharyngeus; Thy) and constrictor (Genioglossus; GG) muscles. After >2 weeks of surgical recovery, responses to saline or various doses of fentanyl citrate (25-125 mcg/kg; IV) were tested for 30 min before and up to 90 min after injection. As described in an adjacent poster, particularly over the first several minutes after fentanyl injection, CA and OA were observed in some goats. However, disruption of airflow was primarily associated with increased simultaneous activation of pump and airway inspiratory and expiratory muscles resembling WCS. For most muscles, the rate of rise in muscle activity (an index of firing intensity) increased within 2 minutes following fentanyl injection and remained significantly (P<0.05) elevated up to 90 minutes. During WCS periods, airflow was oscillatory or interrupted suggesting transient closure of the airway. In addition, there were time- and dose-dependent effects on frequency, duration, and total activity of the pump and airway muscles. By 60 minutes post-injection, there were periods of transient return of muscle activity and airflow to at or below baseline values. There was no significant effect of saline on muscle activity. Overall, these data suggest that following fentanyl injection in awake goats, there was an increase in firing of pump and airway muscles which ultimately disrupts the coordinated reciprocal activity of inspiratory and expiratory muscles and contributes to OIRD. Supported by NIH DA050571 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.