bluuebunny/crossref_metadata_2025_split huggingface dataset:
A circadian zip code determines rhythmic leukocyte trafficking to tissues
Authors: He Wenyan , Kraus Kerstin , Druzd David , de Juan Alba , Ince Louise , Chen Chien‐Sin , Scheiermann Christoph 
Published: November 2023

Circadian rhythms are important in aligning physiological processes to the rhythmic environment most organisms are exposed to. Recent evidence indicates the time‐of‐day to strongly influence the immune response. However, the dynamics of leukocyte migration over the course of the day are unknown. Here, we investigated an oscillatory migration behavior of key leukocyte subpopulations in murine blood, i.e. neutrophils, B cells, CD4 T cells, CD8 T cells, natural killer (NK) cells, NKT cells, eosinophils, inflammatory as well non‐inflammatory monocytes. We observed oscillations in the surface expression of adhesion molecules and chemokine receptors on leukocyte subtypes and endothelial cells of various vascular beds. To test the relevance of these oscillations, we performed function‐blocking experiments using antibodies directed against adhesion molecules, followed by homing assays. Our data indicate VCAM‐1 to be pivotal in the rhythmic recruitment of most leukocytes subsets, whereas ICAM‐1 appears to be involved most prominently in mediating rhythmic homing of T and B lymphocytes. In contrast, individual targeting of ICAM‐2, E‐selectin or P‐selectin yielded no effects on rhythmic recruitment. Furthermore, we explored the role of chemokine receptor (Gαi‐protein)‐mediated signaling in this process by pulsed pre‐incubation of leukocytes with pertussis toxin. These data additionally indicate chemokines as important regulators of rhythmic leukocyte recruitment. Together, our data demonstrate the existence of a concerted, rhythmic leukocyte‐ and tissue‐specific molecular signature in the expression of pro‐migratory factors, which allows for the recruitment of select leukocyte subsets at distinct times.Support or Funding InformationFunded by the German Research Foundation (Emmy Noether SCHE 1645/2‐1 and SFB914 projects B09 and Z03) and the European Research Council (CIRCODE, 635872)
Sympathetic nerves regulate rhythmic leukocyte recruitment to arteries and veins
Authors: de Juan Alba , Druzd David , Zuchtriegel Gabriele , Kraus Kerstin , Reichel Christoph , Scheiermann Christoph 
Published: November 2023

Recent evidence points to a critical role of the time‐of‐day in the regulation of leukocyte recruitment to tissues. Using in vivo quantitative imaging analyses across the day in inflammatory scenarios, we observed circadian (~24h) leukocyte recruitment in arteries and veins of the macro‐ and microvasculature. Interestingly however, while in arteries the number of adherent cells peaked in the morning, in veins it peaked at night. These differences were functionally associated with a vessel‐type‐specific oscillatory pattern in the expression of the adhesion molecule ICAM‐1 but not of other promigratory molecules or clock genes. ICAM‐1‐deficient mice lacked rhythmic leukocyte adhesion in both arteries and veins, which was also observed in studies using functional ICAM‐1‐blocking antibodies. Since the sympathetic nervous system (SNS) is an important orchestrator of rhythmicity in peripheral tissues, we disrupted the SNS systemically by 6‐OHDA treatment. This resulted in a lack of oscillations in both arteries and veins. To assess the functional role of direct sympathetic innervation in this process, we surgically denervated sympathetic input to vessels locally by unilaterally cutting the superior cervical ganglion. While the contralateral, nerve‐intact sides still exhibited rhythmicity in both leukocyte adhesion and ICAM‐1 expression, local denervation resulted in a loss of oscillations. Similar results were obtained by administration of beta adrenergic receptor antagonists. Interestingly, when using Ng2Cre x Bmal1flox/flox mice, in which the core clock gene Bmal1 and thus rhythmicity was selectively deleted in arteriolar Ng2+‐pericytes, an ablation of the oscillations was observed in both arteries and veins. Thus, using pharmacological, surgical and genetic approaches, our data point to an important role of arteries in regulating rhythmic leukocyte recruitment to veins.Support or Funding InformationFunded by the German Research Foundation (Emmy Noether SCHE 1645/2‐1 and SFB914 projects B09 and Z03) and the European Research Council (CIRCODE, 635872)
Impact of Learning Approaches on Academic Performance of Preclinical Medical Students: Superficial Vs Deep
Authors: Kayali Zeina , Abdulwali Fareeha K , Peeran Ahmed A , Obad Adam S , Shareef Mohammad A 
Published: November 2023

IntroductionMedical students often adopt different learning strategies and motives that guide them during studying. Preclinical students often face difficulties coping with new learning environments hence impacting their learning styles. The literature shows that studies examining the influence of surface and deep learning approaches on the academic performance of preclinical students are limited. Hence, this study aims to measure the impact of superficial and deep learning approaches on their academic performance.MethodsThe revised two‐factor version of the Study Process Questionnaire (R‐SPQ‐2F) was distributed among first, second and third year medical students at Alfaisal University. Each learning approach, surface or deep, is composed of motives and strategies. Exploratory factor analysis was conducted to validate the tool and Cronbach's alpha to assess its reliability. GPA was grouped into four groups: excellent (>3.5), good (3.0–3.5), average (2.5 – 2.9) and poor (<2.5). Regression analysis explored the prediction of academic performance by different learning styles. One‐way Analysis of Variance (ANOVA) and independent samples t‐test were used to examine the differences between learning styles, different study resources and average study time.ResultsA total of 159 students were enrolled in the study and the tool was tested to be valid and reliable. Deep learning approach predicted higher academic performance among the students (β 0.26, p=0.001). Excellent students showed higher ratings of deep learning strategies than good (p=0.025) and average students (p=0.001). Students who study for more than 8 hours daily also ranked higher in deep learning strategies than those who study for 4–6 hours (0.024) and 2–4 hours (p=0.01). Additionally, students who read books demonstrated higher self‐rating in deep motives and strategies (p=0.008 & p=0.005, respectively). Those who watch videos and utilize internet to expand medical knowledge tend to have higher ratings in deep motives with p values of 0.038 and 0.019, respectively.ConclusionThis study demonstrates adequate validity and reliability of R‐SPQ‐2F model among the study subjects. Students with deep approach style tend to study for a longer time, use different resources and achieve a higher GPA compared to students with surface approach. This may help students with surface approach shift their learning motivations to deep motives in order to achieve a transition to deep learning approach.
Early Echocardiography experience assists in improving and retaining knowledge of Cardiac Anatomy and Physiology for medical students
Authors: Elmoselhi Adel , Eladl Mohamed , Seif Mohamed 
Published: November 2023

BackgroundEchocardiography (Echo) has become an increasingly valuable tool in clinical patient care. Acquiring the needed skills for its use is now critical for all practitioners. Recently the medical education around the globe has been undergoing a major transformation to prioritize competency and clinical integration with basic medical sciences. Our aim is to explore the feasibility of early echocardiography experience as an effective tool to improve and sustain knowledge of cardiac anatomy and physiology to second‐year medical students.MethodsThe study was conducted on 66 medical students in a problem‐based learning (PBL) curriculum. Students were introduced to cardiac anatomy and physiology as well as the basic principles of ultrasonography before the Echo sessions. A pretest was conducted at the start of the Echo theoretical session, consisting of 10 questions related to anatomical structures and phases of the cardiac cycle. The Echo practical sessions included hands‐on experience on standardized patients with a checklist of structure and function that are commonly demonstrated in left parasternal and apical four chamber windows. An early post‐test with the same questions was repeated immediately after the Echo clinical sessions to test knowledge gained during the sessions. Another late post‐test using the same questions was conducted after five months to test the retention of the student's knowledge. Furthermore, surveys were conducted to gather students' feedback.ResultsThe early post‐test outcome revealed a significant improvement in identifying the cardiac structures and function in comparison to the pre‐test. The mean of the student's scores increased from 6.58 (SD = 1.75) to 9.59 (SD = 1.04) with P value ≤ 0.0001. This significant improvement has been maintained in the late post‐test after five months with a mean of 9.2 (SD = 1.74) with insignificant correlations between post‐test and late post‐test (P Value = 0.12). Furthermore, 95% of students admitted that preceding basic knowledge is essential for identification of Echo images and 86% stated that integrating this experience is helpful in consolidating different phases of the cardiac cycle.ConclusionIntroducing Echo spatial orientation and hands‐on experience in the early years of a medical curriculum seems to improve and enhance the retention of student's knowledge of cardiac anatomy and physiology. The Echo experience was well received and endorsed by the students and needs to be considered in new medical curricula development.Support or Funding InformationN/A
Building Bridges: Addressing Real World Problems with Technology but without a Protocol using Design Instruction in a Physiology Lab
Authors: Vaidyam Aditya , Batts Jacob T , Chan Hayley , Pelaez Nancy 
Published: November 2023

Research methods, physiology equipment, and undergraduate students have changed. The next generation of students readily use social networking tools to informally interact, and memorized knowledge has been devalued since the Internet is always available everywhere. Being able to search the Internet quickly, to find the right information, and to apply it in a lab course to the current culture is imperative to making instruction relevant to biomedical innovation. Unlike most physiology lab courses where students learn about technology (how instruments work, what each does) but with few opportunities to explore, here we describe technology use in a course where components were made available and students were encouraged to build and calibrate their own instruments for addressing a particular problem. Findings show benefits when modular components were used to bring theoretical knowledge closer to ‘real world’ applications with technology. Building their own instrument was more active than using an instrument. Given autonomy to solve problems in real‐life scenarios, the students experimentally tested their own solutions and critiqued how well design features may work. A gap between two ends of the spectrum for students who were learning about technology use was bridged by building from principles to the complex system of research methods done with new technology. Furthermore, time and other costs were a relevant concern when an idea was pitched to a client focused on innovation. In conclusion, the modular components now available for physiology research make it feasible to shift physiology lab courses toward designing and building from scratch an instrument to address a given problem instead of taking measurements to confirm existing knowledge. By doing this, students developed originality and confidence for achieving success collaboratively. Volunteers from other institutions are being recruited to pilot tools and rubrics to support and evaluate online team dialogue for this and other projects like this one.Support or Funding InformationThis work was supported in part by Purdue University Instructional Equipment Funding awards in 2014 and 2016.
Lessons from a hybrid undergraduate Human Biology course
Authors: Seiler Kathleen 
Published: November 2023

Undergraduate online education has increased in popularity in recent years and can used as a means to deliver undergraduate general education science courses. Delivery of laboratory material can be problematic in an online format. The hybrid course delivery method can alleviate this constraint by allowing lecture material to be delivered in an online format with a weekly meeting for in‐person laboratory exercises. This hybrid model was used to deliver a general education science course called Introduction to Human Biology (SCI‐115) at Champlain College in Spring and Fall 2016 semesters. Class sizes were very small (9 students in one section and 14 in another). Information regarding the outcomes of the two courses with student feedback and instructor reflection will be presented.Support or Funding InformationNA
The Wright Cardiac Cycle Table: A Novel Tool to Teach the Cardiac Cycle
Authors: Wright Bruce Eric 
Published: November 2023

The Wiggers Diagram has been the standard tool for teaching the events of the cardiac cycle for nearly 100 years. However, as it often displays related cardiac cycle events on different figures in the diagram, many students have trouble grasping how these components work together to pump blood into arteries. The Wright Cardiac Cycle Table is a new teaching tool that provides a more integrative view.In this four‐row stacked‐figures table, each row displays the events that occur in each phase of the cardiac cycle. From top to bottom, the rows depict the compartmental pressures and other events of 1) slow passive filling of a ventricle (atrial and late ventricular diastole); 2) active filling (atrial systole); 3) active ventricular emptying (ventricular systole); and 4) rapid filling (atrial/early ventricular diastole). Each column represents one of four compartments (venous, atrium, ventricle, and artery) placed in a linear orientation. In the top row (slow filling in diastole), pressures in each compartment are displayed which demonstrate why the atrioventricular valve is open and the other valve (pulmonic or aortic) is closed. A blood bolus is shown following its pressure gradient from the venous compartment into the atrium. The second row displays changes in pressures following the P wave (active filling/atrial systole) and the bolus moving into the ventricle. The third row (ventricular systole) follows QRS. It displays changes in pressures, valve openings and closings, heart sounds, and blood flow from ventricle to artery during this phase. Finally, following the T wave actions of the rapid filling phase of early ventricular diastole are displayed.When the four different rows are stacked one below another the ECG is represented vertically as each wave drives the events of the subsequent phase. One can then track either each column to note which events occur in each compartment over time, or each row for the events that occur in every compartment in each phase of the cardiac cycle. Either the right or left heart can be depicted. Pathologies (e.g. aortic stenosis) can be demonstrated from the point of view of pressure change and/or fluid flow change. If animated, one can also represent filling and emptying of the chambers to further demonstrate changes in volumes of the atrium and ventricle during the cycle. One can also insert start/end volumes numerically into the table but this is not recommended.For sheer detail, nothing can truly replace the Wiggers Diagram. Still, this table has potential to supplement the Wiggers Diagram and reach a population of students who need a more concrete depiction of the cardiac cycle. The author has used this table as a medical teaching tool with great success. Future studies may more adequately assess its effectiveness across a wider group of students.
Flipping the Anatomy and Neuroanatomy Classrooms in the First Year of Dental School
Authors: Druzinsky Robert E , Doubleday Allison F 
Published: November 2023

Over the past few years, faculty in the UIC College of Dentistry have found that attendance at lectures has been poor, often 50% or less, in the first year curriculum. All lectures in the D1 curriculum are recorded automatically using the Echo360 system and these videos are used routinely by students. Pass rates for D1 students at UIC for Part I of the National Board Examination, which is taken in the middle of the second year of the curriculum, have been extremely high ‐ 100% for the past five years. In other words, many of our students are successful in spite of the fact that they rarely attend the lectures in the basic sciences and many students often watch recordings of lectures rather than attend in person.Since students use recorded lectures to study already, we believe that classroom time can be used more productively. Therefore, in the current academic year we are flipping the classroom for many sessions. Rather than presenting new material in the classroom, we ask students to prepare ahead of time by reading from assigned texts and completing various assignments online. We are using several software tools to create these online activities.Rather than simply editing videos from previous years, new videos, usually less than 30 minutes long, are produced. The TechSmith Camtasia© add in for Microsoft Powerpoint© is used to create videos with audio narration over the slides. Presentations are in tablet mode so that the instructor can draw on the slides and the drawings are recorded. The videos opened in Camtasia© where the video and audio are edited. The most recent version of Camtasia© also allows quizzes to be created and added to the videos. Students are required to watch the videos and complete the quizzes before they attend the classroom session. Scores on these quizzes are exported automatically to the Blackboard© gradebook for the class.Applications such as SoftChalk© and Explain Everything©, along with the testing function in Blackboard, are also being used to produce interactive materials that students must finish before coming to the classroom. These activities hold students accountable for the content and act as formative assessment for both faculty and students.Face to face classroom sessions now include very few traditional didactic lectures. Students are quizzed on the relevant material using TurningPoint Cloud©, Kahoot©, and other polling tools. TurningPoint Cloud© is particularly useful because it is very flexible and, like Camtasia©, scores are recorded automatically in Blackboard©. Most of the face to face class time is used as a question and answer session.Although the flipped classroom approach is new to us, and we have no hard data for any real evaluation, we have found that questions asked by students indicate that they are coming to the classroom far better prepared than they have in previous years.
Metal drives chemistry: dual‐function of acireductone dioxygenase enzymes
Authors: Deshpande Aditi Rajiva , Wagenpfeil Karina , Pochapsky Thomas Charles , Petsko Gregory , Ringe Dagmar 
Published: November 2023

Acireductone dioxygenase (ARD) from the methionine salvage pathway of Klebsiella oxytoca is the only known naturally occurring metalloenzyme which exhibits dual‐chemistry in vivo determined solely by the identity of the divalent transition metal ion (Fe2+ or Ni2+) in the active site. The Fe2+ containing isozyme catalyzes the on‐pathway reaction using substrates acireductone and dioxygen to generate formate and the ketoacid precursor of methionine, whereas the Ni2+ containing isozyme uses the same substrates to catalyze an off‐pathway shunt to methylthiopropionate, carbon monoxide and formate. We recently have shown that mammalian homologs of ARD (mouse and human) are also capable of this metal‐dependent dual‐chemistry in vitro. The possibility of this dual chemistry in mammals is interesting since carbon monoxide, one of the products of off‐pathway reaction, is an anti‐apoptotic molecule. In addition, several biochemical and genetic studies have indicated an inhibitory role of human ARD in cancer. Recombinant mouse and human ARD isozymes were expressed and purified to obtain a homogeneous single transition metal (Mn, Fe, Co, Ni) bound form of the enzymes. The Fe2+‐bound ARD showed highest activity compared to the other metal‐bound forms of ARD. Similar to ARD from Klebsiella, both human and mouse ARD bound to Ni2+, Co2+ or Mn2+ catalyzed the off‐pathway reaction whereas Fe2+‐bound ARD catalyzed the on‐pathway reaction of the methionine salvage pathway. Thermal stability indicated a large difference in melting temperatures of the proteins; with Ni2+‐bound ARD being the most stable followed by Co2+ and Fe2+ and Mn2+ being the least stable. Crystal structures of Ni2+‐bound mouse ARD co‐crystallized with product and substrate analogs provided insight into metal coordination, substrate and product binding coordination and catalytic mechanism. Solution NMR data of Fe2+, Ni2+ and Co2+‐bound human ARD isozymes indicate that the metal center imparts significant structural differences to the overall protein structure.Support or Funding InformationThis work was supported in part by a grant from the National Institutes of Health (GM26788 to G.A.P. and D.R.)