bluuebunny/crossref_metadata_2025 huggingface dataset:
En Bloc Dissection of Thoracic and Abdominal Viscera: a Beneficial Approach for Medical Student Learning
Authors: Xi Alan , Kulkarni Namrata , Hankin Mark
Published: June 2021

A typical medical school approach to dissecting the thorax and abdomen begins with removal of the anterior body wall. With the viscera caged in the body cavities, access to dissection is limited, the view is restricted, and critical relationships may be disrupted due to removal of structures. To overcome these challenges, an en bloc dissection of the thoracic and abdominal viscera was experimented, in which the thoracic and abdominal organs, diaphragm, and neurovasculature were removed as a unit for dissection and study. Removal of the visceral block required transecting: (1) structures that traverse the anatomical thoracic inlet, (2) the mural attachments of the diaphragm, and (3) the ureters, rectum, and distal ends of the abdominal aorta and inferior vena cava. This preparation has a number of advantages: (1) a 360° view of the viscera not confined by body wall; (2) increased space for dissection of abdominal organs and neurovasculature; (3) a clear display of relationships between retroperitoneal organs (e.g., kidneys and great vessels); (4) an easier view of the diaphragm in relation to surrounding structures; and (5) unhindered dissection of the posterior abdominal and thoracic walls. In addition, integrity of the thoraco‐abdominal structures (e.g., descending aorta, esophagus, sympathetic chain and vagus nerve) was maintained. First‐year medical students found these preparations to be extremely useful as a supplement to more traditional dissection. We conclude that en bloc dissection of thoracic and abdominal viscera provides advantages that underscore its potential role in anatomy education.
GTP Hydrolysis is Not Required for Post‐translational Protein Insertion by a Chloroplast Signal Recognition Particle
Authors: Sharma Priyanka , Kight Alicia , Goforth Robyn , Henry Ralph
Published: June 2021

Light harvesting chlorophyll binding proteins (LHCPs) are a family of nuclear encoded chloroplast thylakoid proteins that are synthesized in the cytosol, imported into the chloroplast stroma, and subsequently directed to the thylakoid membrane. LHCP targeting/insertion into thylakoid membranes requires GTP, a thylakoid protein insertase, and two prokaryote derived GTPases, chloroplast signal recognition particle (cpSRP) and its membrane receptor (cpFtsY). cpSRP binds LHCP in the stroma to form a soluble targeting complex that is directed to thylakoids owing to affinity of cpSRP for cpFtsY, an interaction requiring GTP. LHCP insertion requires Albino‐3 (Alb3), which stimulates GTP hydrolysis by cpSRP/cpFtsY and releases cpSRP from cpFtsY. The role of GTP in LHCP insertion is less clear. Using assays that reconstitute LHCP integration into isolated thylakoids, we have demonstrated that GTP hydrolysis is not required for LHCP insertion. GMP‐PNP, a non‐hydrolysable analogue of GTP, is sufficient to support LHCP integration. Surprisingly, LHCP integration supported by GMP‐PNP, and not GTP, is sensitive to elevated concentrations of free cpSRP/cpFtsY. Our data supports a mechanism in which guanine nucleotide binding by cpSRP/cpFtsY is required for LHCP release from cpSRP whereas GTP hydrolysis serves to recycle cpSRP from cpFtsY for subsequent rounds of targeting. It is hypothesized that guanine nucleotide binding will only serve to release LHCP from cpSRP in the presence of an available Alb3 insertase to prevent unproductive targeting.
Transport of Alzheimer's Associated Amyloid‐β Through Membranes Catalyzed by P‐Glycoprotein
Authors: McCormick James , Vogel Pia , Wise John
Published: June 2021

The broad range of substrates that can be transported by ABCB1 plasma membrane transporters has been well established. Of these transporters, MDR1 P‐glycoprotein (P‐gp), has been extensively studied and is best known for the abilities to confer general multidrug resistance to populations of cancer cells and for preventing pharmaceutical products from crossing the blood brain barrier (BBB). P‐gp action has recently been also implicated in Alzheimer's disease (AD). One of the clearance pathways of amyloid‐β, thought to be a causative agent in neurodegeneration and symptom onset in AD, is suggested to be through P‐gp across the BBB. In this study, a P‐gp model with amyloid‐β bound to drug binding domains was used in targeted molecular dynamics simulation (TMD) of the catalytic cycle. TMD employed four different crystallographic conformations to move the protein through open inside to open outside conformations. Transport of amyloid‐β through the membrane was observed during the putative catalytic cycles. Results suggest that the catalytic cycle resulted in movement of amyloid‐β to P‐gp structures productive for release to the extracellular space. These simulations have elucidated specific molecular interactions between P‐gp and amyloid‐β that result in amyloid‐β transport. Such studies have enabled a detailed and targeted biochemical analysis of amyloid‐β transport through the BBB. This work is supported by NIH NIGMS [Grant 1R15‐GM094771‐01A1] to PDV and JGW, SMU Research Council, SMU Dean's Research Council, the SMU Center for Drug Discovery, Design and Delivery, and the Communities Foundation of Texas, Dallas.
Development and in silico Evaluation of Large‐Scale Metabolite Identification Methods Using Functional Group Detection for Metabolomics
Authors: Mitchell Joshua , Fan Teresa , Lane Andrew , Moseley Hunter
Published: June 2021

Large‐scale identification of metabolites is key to understanding metabolism at the systems level. Advances in metabolomics technologies, particularly ultra‐high resolution mass spectrometry enable rapid, comprehensive analysis of metabolites that is impractical to achieve by conventional methods. A significant barrier to meaningful data interpretation is the identification of metabolites including unknowns and the determination of their role(s) in metabolic networks. Chemoselective (CS) probes to tag metabolite functional groups combined with high mass accuracy provide additional structural constraints for metabolite identification and quantification. We have developed a novel algorithm that efficiently detects functional groups within existing metabolite databases such as KEGG Ligand and the Human Metabolome Database, allowing for combined molecular formula and functional group queries to aid in metabolite identification without a priori knowledge. Analysis of the isomeric compounds in both HMDB and KEGG demonstrated a high percentage of isomeric molecular formulae (43% and 28% respectively), indicating the necessity for techniques such as CS‐tagging. Furthermore, these databases have only moderate overlap in molecular formulae. Thus, it is prudent to use multiple databases in metabolite assignment, since each major metabolite database represents different portions of metabolism. In silico analysis of CS‐tagging strategies demonstrate that combined FT‐MS derived molecular formulae and CS‐tagging can uniquely identify up to 71% of KEGG and 37% of the combined KEGG/HMDB database compared with 41% and 17% respectively without adduct formation.
Investigation of the cellular mechanism of apoptosis in renal failure during sepsis
Authors: Lampl Thomas , Del Gaizo Moore Victoria
Published: June 2021

Sepsis, a condition that affects 750,000 people per year, is characterized as a severe inflammatory response to infection. Patients exhibit highly increased concentrations of circulating cytokines as a result of their immune response. Consequently, end‐organ failure observed in many septic patients has been linked to these increased cytokine levels, with tissue damage resulting, at least in part, via apoptosis. Specifically, acute kidney injury (AKI) induced by sepsis is a serious problem, and is poorly characterized. This study aims to determine the cellular mechanism of apoptosis during sepsis using an in vitro model of sepsis‐induced AKI. Cultured kidney cells were treated with either cytokines secreted from THP1 cells exposed to LPS, or recombinant cytokines. Then, MTT assays, at various times post‐exposure, were used to measure changes in cell viability. Furthermore, flow cytometry of whole cells stained with Annexin‐V‐FITC determined specifically the amount of apoptosis incurred. Our results show a small, yet significant, decrease in cell viability for cultured cells treated with recombinant cytokines versus untreated cells. Correlated flow cytometry results indicate that the majority of the cell death occurring is in fact due to apoptosis. Additionally, Western blotting, immunoprecipitation, and BH3 profiling assays were conducted to determine which BCL‐2 family proteins may be important in cytokine‐mediated apoptosis. Data from these analyzes suggest anti‐apoptotic BCL‐2 and pro‐apoptotic BIM are key contributors. Further experiments are currently underway using primary kidney cells, and eventually the in vivo cecal ligation and puncture (CLP) model in mice will be employed to give additional insight.
Cloning, Expression and Refolding of the Metacaspase Scp3 of Schizophyllum commune in Brewer's Yeast and E. coli
Authors: Jaksic Alexander , Loew Ethan , Kaminski Anne , Glaser Andrew , Fox Kristin
Published: June 2021

Metacaspases are Arg/Lys specific heterodimeric peptidases that are composed of a p10 and a p20 subunit that induce cell death cascades in fungi, plants and protozoa, making them novel drug‐targets. The fungus Schizophyllum commune contains five genes that code for metacaspases, of which only one, Scp3, has been expressed completely in Escherichia coli. Our overall aim is to produce soluble, active Scp3, however the Scp3 expressed in E. coli has been insoluble and inactive, compelling us to investigate a variety of different methods of expression. Homologous caspase proteins have been successfully produced via expression of the individual p10 and p20 subunits, that are then unfolded, combined and refolded into the active protein. Both subunits have already been cloned into the expression vector, pQE80/82(Qiagen), p20 expression was successful, and expression of p10 is underway in E. coli. In a parallel project we are attempting to express the full‐length Scp3 in E. coli and yeast. The full scp3 gene has been cloned into the pEQ80(Qiagen) and expressed in E. coli. After unfolding in guanidine HCl and refolding by dilution, small‐scale experiments have yielded soluble Scp3. Scp3 has also been cloned into the pYES vector (Invitrogen) and transformed into brewer's yeast, but no expression of Scp3 is observed when yeast are induced with galactose. Our aim is to produce soluble and active Scp3 that can be isolated for structural and functional analysis.
Effect of Obesity on the Hepatotoxicity of High Dose Oral (‐)‐Epigallocatechin‐3‐gallate
Authors: James Karma , Lambert Joshua
Published: June 2021

Fatty liver disease is a co‐morbidity of obesity which is characterized by increased hepatic oxidative stress and increased sensitivity to drug induced liver injury (DILI). Green tea based dietary supplements containing high levels of the polyphenol (‐)‐epigallocatechin‐3‐gallate (EGCG) have become popular for weight loss. Case‐studies have reported hepatotoxicity associated with consumption of green tea‐based supplements and laboratory studies have shown the potential hepatotoxicity of EGCG in animals. With a growing body of evidence of high dose EGCG mediated liver toxicity, and studies showing increased sensitivity to DILI in obese subjects, it is reasonable to hypothesize that obesity may increase susceptibility to EGCG mediated hepatotoxicity. We tested this hypothesis in high fat‐fed obese C57BL/6J mice. Obese and age‐matched lean controls were treated with 0, 500, or 750 mg/kg EGCG by oral gavage, once daily for 2 d. At 500 mg/kg, EGCG treatment increased plasma alanine aminotransferase (ALT) and hepatic malondialdehyde (MDA) levels to a greater extent in obese mice compared to lean, age‐matched controls. By contrast, plasma ALT and hepatic MDA levels were greater in lean mice treated with 750 mg/kg EGCG compared to obese mice. EGCG treatment dose‐dependently reduced hepatic mRNA expression of peroxisome proliferator‐activator receptor g coactivator‐1a and forkhead box O3 in obese mice. Since these genes are related to antioxidant response, further studies are underway to determine the effect of EGCG on the expression and activity of antioxidant enzymes. The results of these experiments provide insight into factors that moderate sensitivity to EGCG mediated hepatotoxicity.
Piezo1 Integration of Vascular Architecture with Physiological Force
Authors: Li Jing , Hou Bing , Muraki Katsuhiko , Ainscough Justin , Beech David
Published: June 2021

The mechanisms by which physical forces regulate endothelial cells to determine the complexities of vascular structure and function are enigmatic. Studies of sensory neurons have suggested Piezo proteins as subunits of Ca2+‐permeable non‐selective cationic channels for detection of noxious mechanical impact. Here we show Piezo1 (Fam38a) channels as sensors of frictional force (shear stress) and determinants of vascular structure in both development and adult physiology. Global or endothelial‐specific disruption of mouse Piezo1 profoundly disturbed the developing vasculature and was embryonic lethal within days of the heart beating. Haploinsufficiency was not lethal but endothelial abnormality was detected in mature vessels. The importance of Piezo1 channels as sensors of blood flow was shown by Piezo1 dependence of shear‐stress‐evoked ionic current and calcium influx in endothelial cells and the ability of exogenous Piezo1 to confer sensitivity to shear stress on otherwise resistant cells. Downstream of this calcium influx there was protease activation and spatial reorganization of endothelial cells to the polarity of the applied force. The data suggest that Piezo1 channels function as pivotal integrators in vascular biology. This work was supported by Welcome trust and Medical Research Council.
Impact of Aging on Aortic Wave Reflection during Lower Body Negative Pressure
Authors: Schneider Aaron , Barnes Jill , Joyner Michael , Casey Darren
Published: June 2021

Evidence suggests that increased sympathetic tone but no change of blood pressure (BP) via lower body negative pressure (LBNP) reduces indices of aortic wave reflection in young adults. The aim of this study was to examine whether aging affects central artery hemodynamics and indices of wave reflection during LBNP. In 12 young (27 ± 2 years, 5F/7M) and 10 older (70 ± 2 years 5F/5M) subjects, noninvasive aortic pressure waveforms were synthesized from high‐fidelity radial pressure waveforms via applanation tonometry before and during 10 minutes of LBNP (‐20mmHg). Aortic BP and indices of aortic wave reflection (i.e. Augmentation index; AIx) were calculated from the generated aortic pressure waveform. Aortic systolic BP decreased during LBNP in the young (110 ± 3 vs. 106 ± 3 mmHg, P<0.05), but not the older adults (139 ± 3 vs. 136 ± 3 mmHg, P=0.15). Aortic diastolic BP did not change in either group (P=0.56). Since heart rate (HR) changed in the young (P<0.05) but not in the older adults (P=0.33) during LBNP, we used the AIx normalized to a HR of 75bpm as an index of wave reflection. AIx@75bpm decreased in young adults (‐6 ± 3 vs. ‐13 ± 3%, P<0.001), whereas no change was observed in older adults (26 ± 3 vs. 25 ± 3%, P=0.39). Our data suggest that reductions in aortic systolic blood pressure and wave reflection during lower body negative pressure are attenuated in older compared to young adults.

Funded by NIH HL‐105467
Computational Analysis of Cellular Environment During Neural Progenitor Cell Differentiation
Authors: Mahadevan Arun , Robinson Jacob , Qutub Amina
Published: June 2021

Objective

The objective of this study is to quantify the influence of multi‐cellular environment in Neural Progenitor Cell (NPC) differentiation using time‐lapse phase contrast microscopy.

Methods

Differentiating human NPCs were tracked over 14 days using time‐lapse phase contrast microscopy.

image

An intensity‐gradient thresholding method was used to extract cell locations and morphological features such as neurite length. A graph theory‐based approach was then employed to quantify cellular neighborhood, with vertices defined as cell centroids and spatial proximity between cells used to define edges.

image

Global network properties such as characteristic path length and global clustering coefficient were evaluated at each time point to quantify the spatial topology of differentiating cells. Parallel assays in patch‐clamp electrophysiology were performed to compare functional maturation with network properties.

Results

Our image‐processing algorithm rapidly and robustly extracts relevant cell morphological features and locations. Time‐lapse image sequence analysis showed that cultures at different stages of electrical maturation (assayed through patch clamp electrophysiology) exhibit unique network topology.

Conclusion

We have developed a method to analyze NPC differentiation based on time‐lapse microscopy, which can be used to non‐invasively investigate the role of multi‐cellular neighborhood at different stages of NPC differentiation.

Support

This work is supported in part by NSF CAREER Award 1150645 and an NSF IGERT Training Grant.
Relationship of Age to Respiratory Muscle Strength and Mortality in Mechanically Ventilated MICU Patients HL113494, HL112085
Authors: Supinski Gerald , Callahan Leigh Ann
Published: June 2021

Aging is associated with increased mortality in critical illness. It is thought that this higher mortality is due to the development of more severe organ failure in older patients. We examined the relationship of age to diaphragm strength, lung mechanics, the SOFA (severity of organ failure) score, and survival in 57 mechanically ventilated patients. We assessed: (a) Pdi Twitch (transdiaphragmatic twitch pressure) (b) maximum inspiratory pressure, (c) respiratory compliance, (d) airway resistance, (e) length of ventilator dependence, and (f) mortality. Age ranged from 22 to 85 years. There was not a statistically significant variation of either Pdi twitch, MIP, compliance, resistance, SOFA, or the time on mechanical ventilation as a function of age. Death occurred in 18 patients due to withdrawal of life support, and in 12 of these, mechanical ventilation was the only form of support withdrawn. There was a higher mortality in patients > 55 years of age than in younger patients (p=0.05). This increase in mortality with aging could not be explained on the basis of greater organ failure or more severe weakness. In summary, the most common mechanism of death in the intensive care unit is withdrawal of mechanical ventilation in patients with respiratory failure. This occurs more frequently in older patients despite the fact that these patients do not develop more weakness or greater organ failure during critical illness when compared to younger patients. These data indicate that the greater rate of care withdrawal in older patients is based on factors other than their level of physiologic impairments
The Pseudomonas aeruginosa virulence factor Cif inhibits the generation of the pro‐resolving lipid mediator 15‐epi lipoxin A4
Authors: Bomberger Jennifer , Flitter Becca , Ono Emiko , Hvorecny Kelli , Bahl Christopher , Madden Dean , Levy Bruce
Published: June 2021

Pseudomonas aeruginosa is an opportunistic Gram‐negative bacteria that causes a wide range of severe nosocomial infections, especially in immunocompromised patients with chronic inflammatory lung disease. P. aeruginosa infections are characterized by persistent and robust neutrophilic inflammation which can cause damage to host tissue. Lipoxins, including 15‐epi‐lipoxin A4 (15‐epi‐LXA4), are lipid mediators that play a critical role in resolving inflammation and promoting tissue homeostasis.The production of 14,15‐epoxy‐eicosatrienoic acid (14,15‐EET) by airway epithelial cells stimulates the generation of 15‐epi‐LXA4 by neighboring neutrophils through transcellular biosynthesis. We have identified a P. aeruginosa virulence factor with epoxide hydrolase activity called cystic fibrosis inhibitory factor (Cif), which we hypothesize disrupts the generation of 15‐epi‐LXA4. We show that both P. aeruginosa and recombinant Cif protein alone hydrolyzes the epoxide moiety of (14,15‐EET), whereas a cif deletion mutant P. aeruginosa or catalytically‐dead D129S mutant of Cif have no effect. Furthermore, the Cif‐mediated reduction of 14,15‐EET inhibited the generation of 15‐epi‐LXA4 by activated neutrophils in vitro. The D129S mutant Cif was also incapable of reducing 15‐epi‐LXA4 biosynthesis.Taken together, our data suggest a novel model whereby the P. aeruginosa virulence factor Cif reduces 15‐epi‐LXA4 in the airways, thus promoting persistent inflammation and consequent lung damage.
Inhibition of trophoblast invasion by the growth arrest‐specific 6 (Gas6) protein
Authors: Mejia Camilo , Johnston Andrew , Lutz Rebecca , Arroyo Juan , Reynolds Paul
Published: June 2021

Preeclampsia (PE) is a complicated obstetric complication characterized by increased blood pressure and decreased trophoblast invasion. The growth arrest‐specific 6 (Gas6) protein is known to induce different responses in cells including prevention of apoptosis and enhanced cell migration and invasion. This protein is secreted in response to growth arrest and it is increased during PE. Gas6 binds and induces signaling through the AXL receptor tyrosine kinase. Our objective was to identify expression of AXL in human control and PE placentas and to determine the role of Gas6 in trophoblast invasion as compared to cancer cells. Human control and PE placental samples were collected shortly after delivery. Tissues were frozen in liquid nitrogen for western blot studies or embedded for histological analysis. First trimester trophoblast cells were treated with Gas6 and invasion was measured using an xCELLigence RTCA DP (Real Time Cell Analysis Dual Plate) instrument. We observed: 1) AXL localization to the placental trophoblast cells; 2) decreased AXL expression in the syncytiotrophoblast of the PE placenta; 3) a 15% (p<0.05) decrease in trophoblast invasion after 24 hours of Gas6 treatment; and 4) a 36% increase (p<0.05) in cell invasion of A549 human adenocarcinoma cells after 24 hours of Gas6 treatment. We conclude that AXL receptor expression is decreased in the PE placenta and that Gas6 does not induce invasion in trophoblast cells. These results give insight into pathways associated with increased Gas6 observed during PE and could be useful in the clarifying potential mechanisms that orchestrate decreased trophoblast invasion in PE. (Supported by NIH grant 7K99HD055054‐02).
EXPLORING THE CORRELATION BETWEEN INTRINSIC FLUORESCENCE AND PROTEIN AGGREGATION
Authors: Bennett Christopher , Alibeik Sara , Valverde Paloma
Published: June 2021

Progressive nerve and brain cell damage associated with Alzheimer's disease, has been attributed to the build‐up of aggregated proteins. Detection of amyloid aggregation, through the measuring their intrinsic fluorescence, could be a valuable approach for early detection of the disease.

The purpose of our study was to teach the correlation between intrinsic fluorescence and protein aggregation within the visible range in an interdisciplinary undergraduate summer research course. Students used purified green fluorescent protein (GFP, Biorad), unpurified enhanced green fluorescent protein (EGFP, Edvotek) and liquid silk fibroin protein (SFP, Silktap) as model proteins. We focused our experimentation on sonication conditions that led to gelation of SFP due to β‐sheet formation. Using single model proteins and combined protein solutions, samples were sonicated and fluorescence was measured at 405 and 500nm wavelengths. UV light was also used to compare the green fluorescence emitted by the GFP and EGFP samples.

Our results showed an increase in fluorescence of single model protein solutions post‐sonication when compared with the pre‐sonication protein solutions. When EGFP and SFP solutions were combined and sonicated together, we observed a decrease in fluorescence. Similar results were obtained when purified GFP and SFP solutions were combined and sonicated.

In future experiments, students are planning to design a minimally invasive device able to detect early stages of amyloid aggregation in the brain as a senior project for an undergraduate biomedical engineering major.
Using Generalizability Analysis to Establish Guidelines for Designing Horizontally Integrated Anatomy Assessments
Authors: Byram Jessica , McAteer James , Seifert Mark , Wilson Adam
Published: June 2021

Background & Purpose

In the context of planning assessments for a combined gross anatomy/histology course, this study used generalizability analysis to estimate the number of gross anatomy and histology items that would be needed on a series of examinations to reliably assess discipline‐specific knowledge.

Methods

Scores of first‐year medical students (n=145) who sat for 3 gross anatomy and histology written and practical examinations were analyzed. A generalizability study (G‐study) estimated the reliability of the written and practical examination scores, and a decision study (D‐study) estimated the optimum assessment parameters for reaching a minimum reliability of 0.8.

Results

Estimated G coefficients for calculating reliability were 蠅0.782 for the gross anatomy examinations and 蠅0.659 for the histology examinations. Assuming that a series of 4 separate examinations would be ideal for assessing a breadth of content in a combined gross anatomy/histology course, the D‐study estimated that a minimum of 35 and 40 items for a gross anatomy written and practical examination, respectively, would be needed to reach a reliability of 0.8 for measuring gross anatomy knowledge alone. Furthermore, each of the 4 examinations would require an additional 40 written and 45 practical items to reliability assess one's knowledge of histology.

Conclusion

This study helps to establish basic parameters for designing horizontally integrated anatomy assessments. Future studies will investigate how incorporating ‘truly integrated items' (that require knowledge of histology and gross anatomy to answer a single question) may affect the reliability of such assessments.
Effective Medical Education Resource Design and Integrative Learning: A Lesson in Autosomal Recessive Polycystic Kidney Disease
Authors: Gonzales Fred , Post Miriam , Lee Lisa
Published: June 2021

Autosomal Recessive Polycystic Kidney Disease (ARPKD) is the most common ciliopathy affecting children and has a diverse penetrance. Health care practitioners must be aware of the varying phenotypes and pathophysiology during embryonic development so that proper management and counseling options may be considered. With limited instructional contact hours during training, effective online learning resources are becoming increasingly important. The objective of this project was to create an interactive, online learning module to provide a comprehensive and integrated lesson on ARPKD and to evaluate its educational value at different years of training. The module was created using an actual ARPKD case integrated with a normal development tutorial and self‐assessment tools that provide instant feedback for reinforcement of the material. The module was given to first‐year medical students, graduate students and pathology residents in various years of training. The educational value of the module was evaluated by a user survey and quantitative comparison between pre‐ and post‐test scores, assessed before and after utilizing the module. A retention study was conducted thirty days after completion of the module to determine the long‐term educational value of this teaching modality. The results show that the interactive and clinically oriented module effectively promoted learning and retention, and was positively received by trainees in all stages. Stand‐alone, online learning modules that present clinical cases in a highly integrated manner show promise as an effective undergraduate and graduate medical education tool.
The Impact of Ultrasound Education in Medical Gross Anatomy on Student Experience During Clinical Rotations
Authors: Zoll Kyle , Arseneaux Mattie , Atieh Tahani , Beatty Derek , Kondrashova Tatyana , Kondrashov Peter
Published: June 2021

Objective

To show the effect of ultrasound education on clinical rotations, we surveyed students at the conclusion of their third year and evaluated their perception of: (1) how ultrasound training in gross anatomy impacted their clinical thinking; (2) how often they were able to use ultrasound; (3) the obstacles that prevented them from using ultrasound; and (4) the specialties in which students were able to use ultrasound most.

Methods

Osteopathic medical students received ultrasound training as part of their anatomy course during the first two years of their education. At the conclusion of their first year of clinical rotations, 85 students were surveyed about the impact that ultrasound training had on their clinical thinking, and if they were able to use their skills.

Results

The students thought that ultrasound training had a significant effect on their clinical decision making during their first year of rotations (P<.05). Students were able to use their ultrasound skills during clinical rotations (P<.05). Many students experienced at least one obstacle preventing them from using ultrasound. The most common cause was lack of permission (P<.05). They also listed shortage of equipment and lack of confidence as other obstacles. Ultrasound was most commonly used during obstetrics/gynecology rotations (P<.05).

Conclusion

Ultrasound training had a strong impact on clinical rotations and aided in student decision‐making ability. Ultrasound was used in a variety of specialties throughout clinical rotations. Despite encountering obstacles, the current study supports the inclusion of ultrasound into medical school curriculum as it improves clinical thinking and skills during clinical rotations.
Investigating the Molecular Genetics of Alcohol Dependence: SWSN‐9 Influences Acute Functional Tolerance Development in C. elegans
Authors: Austin Makeda , Blackwell Gina , Mathies Laura , Bettinger Jill
Published: June 2021

Alcoholism is a serious health concern. It is known that an individual's acute ethanol response has significant impacts on the development of alcohol dependence. This study investigated what effect the SWI/SNF chromatin remodeling complex has on acute ethanol response phenotypes. SWI/SNF influences transcription by modifying nucleosome position, thus altering gene expression. Using the simple genetic model, Caenorhabditis elegans, we tested one member of the SWI/SNF complex, SWSN‐9. We tested its role in ethanol responses and examined behavioral effects. It was hypothesized that SWSN‐9 would influence the development of acute functional tolerance (AFT). AFT is defined as a decrease in the intoxicating effects of ethanol during a single continued exposure to a drug, and is indicative of neural adaptation to ethanol effects. Locomotion speed assays were conducted, and we observed the development of AFT by observing an increase in speed over continued ethanol exposure. We compared AFT development of the wild‐type and the mutant strain, which is missing the swsn‐9 DNA sequence. Relative speed comparisons, tested at 0mM and 400mM concentrations of ethanol, indicate that AFT development by swsn‐9 mutants has a statistically significant defect relative to wild‐type. Subsequent rescue methods utilized extra‐chromosomal array injections, followed by gamma irradiation of the C. elegans for full array integration. Locomotion analyses indicate that one rescue strain exhibits AFT similar to wild‐type. We conclude that SWSN‐9 is influencing ethanol tolerance in C. elegans. Further study is necessary to determine where genes are necessary for phenotypic expression.
Analysis of Mutant Constructs of Human BIK and their Interaction with KSHV vBCL‐2
Authors: Normand Caitlyn , Kumarjiguda Deepa , Roecklein‐Canfield Jennifer
Published: June 2021

Kaposi's sarcoma‐associated herpesvirus (KSHV) is a skin cancer caused by a gamma‐ herpesvirus.The virus is a “tumor” transforming virus and thus often leads to cancer in the infected patient. Its association with AIDS over the past two decades has brought increased attention to the roll viral infection plays in the evolution of cancer. KSHV has been shown to interfere in one major pathway that controls cell growth, the apoptotic pathway, important for the maintenance of normal growth and development. Viruses require a live cell for survival and have evolved a mechanism to interfere with apoptosis to create immortal cell hosts. The virus expresses a protein, vBCL‐2 that interferes with pro‐apoptotic proteins and promotes tumor growth. This viral protein is a functional homology of the human Bcl2 protein and has been shown to interact with several BH3 domain containing family members. Previously we had identified an interaction between the KSHV vBcl2 protein and the human BH3 domain containing protein, BIK using the Yeast Two Hybrid System. Current studies have demonstrated critical residues in the BH3 domain of the host Bcl2 family member, BAK, that are critical for vBcl2 interaction. We generated mutants with amino acid substitutions in homologous residues in the BH3 domain of the BIK protein to elucidate the binding interface in this interaction. Using the yeast two hybrid (Y2H) assay and biochemical methods, we analyzed the effect the mutations had on the vBcl2‐hBIK interaction. Identification of the critical amino acid residues in the BH3 domain of BIK will provide valuable insight into the mechanism of viral invasion of the cell and aid in the development of drug targets to prevent tumor development.
Protein Engineering of Coenzyme‐A‐Dependent Aldehyde Dehydrogenase for Commercial Scale 1,4‐Butanediol Production in Escherichia coli
Authors: Shah Amit , Liu Wayne , Kinley Brian , Kuchinskas Mike , Chan Kui , Steer Brian , Li Jingyi , Yim Harry
Published: June 2021

Genomatica has developed a novel commercial process, the GENO BDO™ process, for direct production of the intermediate 1,4‐butanediol (BDO) from carbohydrate feedstocks. BDO is used in a variety of polymer applications, including polyurethanes and polyesters, with over 1.7 million tons of BDO produced annually. Genomatica has leveraged its integrated metabolic engineering platform to maximize carbon flux through the BDO synthetic pathway. This heterologous pathway includes a coenzyme‐A‐dependent aldehyde dehydrogenase (Ald), which catalyzes the conversion of 4‐hydroxybutryl‐CoA to 4‐hydroxybutyraldehyde in the presence of reduced cofactor. Genomatica has performed extensive protein engineering on this enzyme to develop an Ald biocatalyst with increased substrate specificity that can support the required high flux over the course of the entire fermentation. In this poster, the biochemical characteristics of the Ald variants and their impact on performance will be highlighted.
Physiological Characterization of Arginine Kinase Found in Caenorhabditis elegans
Authors: Simonis Dempsey , Chin Melanie
Published: June 2021

Phosphagen kinases (PKs) are a family of enzymes that catalyze the reversible transfer of the high‐energy phosphate group of ATP to a guanidino containing substrate molecule. PKs are involved in maintaining energy homeostasis in response to a sudden, high‐energy demand. There are eight classes of phosphagen kinases based on the substrate they bind. Of these, creatine kinase (CK), found in vertebrates, and arginine kinase (AK), found in invertebrates, are the most widely studied. It has been proposed that AK is the most ancestral PK, and that the others, including CK, have evolved from the AK enzyme. CKs have been well studied physiologically in mice and previous experiments in mice that lack CK isoforms found decreased stress tolerance, decreased muscle function, and increased amounts of mitochondrial volume. By comparison, less is known about the AKs and their role in cellular physiology. We are exploring the potential of using an invertebrate model system for the study of the physiological role of AKs. To facilitate this, we have worked with the C. elegans Genetics Consortium at the University of Oklahoma's Advanced Center for Genome Technology to construct knockouts of four of the AKs in C. elegans. Two of these, W10 and F44 were genetically backcrossed with wild type to isolate the deletion in a wild type background. Through comparison to a wild type strain, the impact that each missing AK isoform has on physiological characteristics, such as aging, energy availability, and burst activity of muscle, will be examined. By comparing two distantly related organisms, with similar PK systems, it is our goal to identify conserved physiological functions of the PK family of enzymes.
Kinetic Analysis of the Processivity of Human Cytochrome P450 17A1
Authors: Gonzalez Eric , Nagy Leslie , Guengerich Frederick
Published: June 2021

Human cytochrome P450 (P450) 17A1 is one of several P450 monoxygenases involved in the biosynthesis of steroids. Notably, P450 17A1 is responsible for 17α‐hydroxylation of the 21‐carbon steroids pregnenolone and progesterone, which are used in glucocorticoid production. 17α‐Hydroxypregnenolone and 17α‐hydroxyprogesterone are also further oxidized by P450 17A1 in a 17α,20‐lyase reaction generating the 19‐carbon androgens dehydroepiandrosterone and androstenendione, respectively. Selective stimulation of the 17α,20‐lyase reaction is observed with human cytochrome b5 (b5). Inhibition of P450 17A1 is a goal in some cancer therapies because of its role in generating sex hormone precursors through the cleavage reaction. However, complete inhibition of the enzyme concomitantly impedes glucocorticoid synthesis. This issue poses the question of whether the 17α,20‐lyase reaction succeeds 17α‐hydroxylation in a successive or distributive manner. To date, the processivity of human P450 17A1 (with and without b5) has yet to be systematically determined. Steady‐state kinetic parameters have been measured for human P450 17A1 reactions and binding constants have been obtained via spectral titrations. Pulse‐chase assays using radio‐labeled substrates and pre‐steady‐state analyses further elucidate the rate constants of key steps in the two‐reaction mechanism for both steroids. Human P450 17A1 is partially processive with pregnenolone. The kinetic analyses yield data to further model the processivity in the presence and absence of b5 utilizing KinTek Explorer® software.
Anthropometric Profile and Rate of Sweating in Women Soccer Athletes
Authors: Chaud Daniela , Apollinario Vanessa , Abreu Edeli , Rossi Luciana
Published: June 2021

Soccer is a sport that arouses most interest in young people, adults and elderly of both sexes. Soccer requires intense energy expenditure during practice, games and competitions, including quick race, explosion, endurance training, jumping, strength and flexibility exercises. The aim of this study was to evaluate the anthropometric profile and determine sweating rate (SR) and risk of dehydration percentage in women Soccer athletes. Anthropometric data was collected regarding weight, height and three skinfolds, and from these the body mass index and body fat percentage were calculated. 15 Soccer players female, who had averaged 26.1 (2.9) years, 61.8 (8.0) kg and 162.2 (5.1) cm participated. The BMI was 23.5 (3.1) kg/m2 and 28.5% G (3,7), classifying them as eutrophic with body fat excess. The hydration status after competitive training, we obtained SR 0.3 (0.1) L/h and Water Déficit (WD) 0.5% (0.2)%. Thus, despite the low risk of dehydration rehydration no specific recommendations were found, and shall remain the guidance of weighing before and after to situation water monitoring, in view of the adverse weather conditions for the competitive practice in a tropical climate country.
C/EBP‐beta Regulates Lipid Homeostasis and Autophagy Activation in Liver and Macrophages
Authors: ZAHID MD KHURSHIDUL , Doyel Allie , Janssen Rachel , Wang Shu , Friedman Jacob , Rahman Shaikh
Published: June 2021

Hyperlipidemia and macrophage foam cell formation result from dysregulation of lipid metabolism and are associated with obesity and atherosclerosis. Autophagy is a lysosomal degradative pathway that plays a crucial role in the metabolism and storage of cellular lipids. However, the molecular connection between autophagy and lipid homeostasis remains elusive. CCAAT/enhancer binding protein‐beta(C/EBPb) is a transcription factor and an important regulator of hepatic steatosis, inflammation, and ER stress. However, whether C/EBPb plays a role in lipid balance in liver and macrophage foam cells via interacting with autophagy machinery remains unexplored. The present study demonstrated that hematopoietic C/EBPb deletion in ApoE‐/‐(C/EBPb‐/‐→ApoE‐/‐) mice attenuated high fat/high cholesterol(HF/HC) diet (11 wks.) mediated induction of hepatic and serum cholesterol levels and genes implicated in TG (fatty acid synthase, stearoyl‐CoA desaturase) and cholesterol metabolism (HMG‐CoA reductase) compared to control (WT→ApoE‐/‐) mice. In addition, increased expression of autophagy protein (ATG5) and reduction of inflammasome activation were found in liver of (C/EBPb‐/‐→ApoE‐/‐) mice. Interestingly, silencing of C/EBPb in RAW 264.7 macrophage cells prevented atherogenic lipid mediated foam cell formation and cholesterol accumulation but increased autophagy activation, and cholesterol efflux. The present results suggest that C/EBPb may interact with autophagy machinery to regulate lipid metabolism in liver and macrophage foam cells. Funded by AHA Beginning Grant In Aid and Startup Fund (Texas Tech University).
SATIN (Satiety Innovation)Project: Dietary Supplementation with Type 3 Resistant Starch Induces Distinct Changes in Gut Microbiota of Overweight Human Volunteers
Authors: Bonnema Angela , Kelly Jennifer , Ryan Sheila , McKinnon Hannah , Romero‐Gonzalez Reyna , Louis Petra , Bosscher Douwina , Duncan Sylvia , Johnstone Alexandra , Flint Harry , Harrold Joanne , Halford Jason , Shirazi‐Beechey Soraya
Published: June 2021

The dramatic increase in obesity and associated diseases has focused interest on the influence of dietary ingredients in controlling satiety. Dietary resistant starch (RS), which undergoes colonic microbial fermentation, has been associated with increased levels of satiety. The work utilized 16S rRNA sequencing to characterize changes occurring in the intestinal microbiota following dietary supplementation with an RS type 3 (ActiStar® 11700, Cargill). RS consumption significantly altered the gut microbiota by enriching a distinct group of taxa, including the primary starch degrader Ruminococcus bromii, and the major butyrate producer Eubacterium rectale; both increasing in over 84% of subjects (p<0.05). RS also caused an increase of Bifidobacterium adolescentis and Faecalibacterium prausnitzii in the majority of subjects, albeit not significantly. The enrichment of these two species has not been previously demonstrated in humans. In summary, we show that the incorporation of RS into the diet significantly changes the faecal microbiota by enriching a distinct group of bacteria involved with starch fermentation and/or butyrate production.
The Long‐Term Impact of Water and Sanitation on Childhood Cognition
Authors: Wulan Nisaa' , Smith Emily , Prado Elizabeth , Apriatni Mandri , Muadz Husni , Shankar Anuraj
Published: June 2021

Unsafe water and poor sanitation may negatively affect brain development, however few studies have examined the long‐term impact on children's cognitive function.

Our objective was to assess the relationship between household access to safe water and toilet facilities during the prenatal period with childhood cognition 9‐12 years later.

The Supplementation with Multiple Micronutrients Intervention Trial (SUMMIT), conducted in 2001‐2004 In Indonesia, compared the health effects of a prenatal multiple micronutrient supplement to an iron and folic acid supplement. At baseline, information collected included water supply, sanitation, and maternal education. We assessed cognition in 3687 children of SUMMIT participants at 9‐12 years of age. Children of mothers who had access to safe toilet facilities during pregnancy had higher scores in Digit Span Forward (95%CI 0.008‐0.17, P<0.03), Information (95%CI 0.08‐0.2, P<0.001), Block Design (95%CI 0.01‐0.1, P<0.02), and Word List Memory (95%CI 0.006‐0.17, P<0.03) tests after adjusting for cluster randomization, data collector, maternal education, socio‐economic status and home environment score. Children of mothers with access to safe water during pregnancy had higher Word List Memory scores (95%CI 0.01‐0.19, P<0.02).

The finding that safe water and toilet facilities were associated with child cognition even after adjustment for socio‐economic status and maternal education suggests that interventions to improve water and sanitation in early life may have long‐term benefits on child cognitive abilities.
Members of the CCN Family of Matricellular Proteins are Required for the Formation and Maintenance of Multiple Skeletal Tissues
Authors: Lyons Karen
Published: June 2021

The roles of members of the CCN (Cyr61/CTGF/Nov) family of matricellular proteins have been best characterized in the context of fibrosis. It is clear that CCNs also have roles in normal tissues, but these are less well characterized. Moreover, CCN1 has anti‐fibrotic properties, whereas CCN2 is profibrotic, indicating that these CCNs have unique functions in fibrosis. Multiple CCN family members are expressed in skeletal tissues, including bone and tendon. The objective of this study was to examine whether various CCN family members are required in these tissues, and whether or not they may have divergent functions during development, as is the case in fibrotic conditions. We therefore generated mice lacking CCN1 (Cyr61) or CCN2 (CTGF) in osteoblasts using osteoblast‐specific Cre drivers, and in tendon using Scx‐Cre. Mice lacking CCN1 or CCN2 in osteoblasts exhibited an osteopenic phenotype, suggesting that CCN1 and CCN2 have some overlapping functions in osteoblasts. Studies are ongoing to define the impact of CCN1 and CCN2 on osteoblast survival, proliferation, and differentiation. Moreover, these studies revealed a unique role for CCN1 in a subset of tendons in the mouse. In the absence of CCN1, tendon fibroblasts acquire a fibrotic phenotype. Thus, the antifibrotic properties of CCN1 that have been demonstrated in the context of pathological conditions are required for the normal formation of organized extracellular matrix in the tendon. Our results thus indicate that CCN1 and CCN2 have both overlapping and opposing functions, depending on the cell type. The mechanisms leading to these differential activities of CCN1 and CCN2 are under investigation.

These studies were supported by NIH AR052686 and the Jonsson Comprehensive Cancer Center, UCLA (KML)