bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human Apolipoprotein E Isoforms Influence Neurite Outgrowth and Regeneration In Vitro and In Vivo
Authors: Maggard Rachel Susanne Jolly , Calulot Christopher M. , Hager Lydia E. , Ritter Kyle J. , Turba Brittany N. , Hoffman Jared D. , Lin Ai‐Ling , Johnson Lance A. , Alilain Warren J. 
Published: June 2021

Translating spinal cord injury (SCI) therapies which promote axonal regeneration from preclinical animal models into the human population is challenging. One potential obstacle is that human genetic predispositions may limit the efficacy of such experimental treatments. The clinically relevant ApoE4 (E4) allele, present in about 14% of the human population, corresponds to an increased incidence of Alzheimer's disease—however, its role in recovery from SCI is poorly understood despite suggestive data implicating its involvement. Indeed, two clinical studies found that SCI individuals with the E4 allele had less motor recovery than individuals without the allele despite longer time in rehabilitation. ApoE4 may mediate this diminished recovery by limiting regeneration and sprouting. Robust regeneration is energy intensive and requires efficient mitochondria, and studies have shown that ApoE4 impairs mitochondrial function. Given these mitochondrial deficits, we hypothesize that ApoE4 can impair regeneration and sprouting. To test this hypothesis, we investigated the impact of ApoE4 on sprouting and neurite outgrowth. In our experiments, we cultured dorsal root ganglia neurons from mice expressing human ApoE isoforms—ApoE2 (E2), ApoE3 (E3), or ApoE4—under the control of the endogenous mouse ApoE promoter. We then analyzed differences in 1) neurite complexity and 2) robustness of outgrowth between genotypes. In two of three independent experiments, E4 neurons had decreased neurite outgrowth and decreased neurite branching compared to E2 and E3 neurons. Data from the Spot Assay, an in vitro model of the glial scar and CNS regeneration, also suggest that chondroitin sulfate proteoglycans may inhibit regeneration in E4 neurons to an even greater extent than in E3 neurons. In addition, with preliminary in vivo data, we are beginning to characterize serotonergic sprouting after lateral C2 hemisection in mice of each ApoE genotype. Since outgrowth, sprouting, and regeneration all partially mediate recovery after CNS injury, impairments in these processes can adversely affect recovery. These foundational studies address not only the possible genetic influence of ApoE4 on recovery from CNS injury, but also a critical gap in knowledge—whether there is a genetic contribution underlying responses to treatment in SCI individuals.Support or Funding InformationUniversity of Kentucky Startup FundsThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Lipopolysaccharide Differentially Alters Oligodendrocyte Precursor Cell Proliferation
Authors: McKinley Raechel Elaine , Ghaderzadeh Sadaf , Csoka Antonei 
Published: June 2021

Multiple Sclerosis (MS) is a debilitating autoimmune disease that impacts 2.3 million people worldwide. In the pathogenesis of the disease, specialized nervous cells called Oligodendrocytes (OLs) are targeted and damaged. When OLs are damaged by the immune system, myelin is destroyed resulting in neuronal cell death. In the adult brain, pools of progenitor cells called Oligodendrocyte Precursor Cells (OPCs) are proliferated, migrated and differentiated to replace and repair mature OLs in the process called remyelination. However, in MS this process does not occur properly. Many factors such as inflammation contribute to the lack of proper remyelination. Moreover, in MS patients, it has been shown that there are increases in Toll‐Like receptors (TLRs). To determine if TLR2 and TLR4 activation plays a role in the proliferation step of remyelination, we treated Induced Pluripotent Stem cell derived OPCs with LPS and hypothesized that LPS treatments will increase the proliferation of OPCs through TLR4 and TLR2 activation. To analyze cell proliferation, a methylthiazol tetrazolium (MTT) assay and immunocytochemistry staining was conducted. Altogether, we found that LPS altered OPC cell proliferation in a dose dependent manner.Support or Funding InformationNational Institute of Health (NIH) R25 Resource Grant. (1 R25 AG047843‐01)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Ontogeny of Southern Cassowary, Maleo, and Helmeted Guinea Fowl Casques: Implications for the Study of Bony Patterning in Non‐avian Dinosaur Cranial Ornaments
Authors: Green Todd , Gignac Paul 
Published: June 2021

Cranial ornamentations (e.g. horns, domes, ridges, rugosities, crests, casques)—some intricately comprised of numerous bony elements—are common among living and extinct archosaurs. Yet, the developmental processes and selective regimes that bring about these metabolically expensive and seemingly bizarre structures remains a mystery. Such features have independently evolved at least 11 times among birds and are varied in their external morphology. Keratinous sheathing and obliterated sutures in late‐stage development have led to contradictory interpretations of cranial osteology for these species and has left it unclear whether the internal morphology of underlying bones of different casqued birds is arranged in a similar fashion. Here we compare the ontogeny for three of the independent casque acquisitions among Aves to clarify their constituent parts. To evaluate the null hypothesis that avian cranial ornaments possess similar anatomical patterns, we analyzed developmental series of skulls of southern cassowaries (Casuarius casuarius), maleos (Macrocephalon maleo), and helmeted guinea fowl (Numida meleagris) using μCT imaging. Sampling neonates and juveniles with incipient casques allowed us to track telescoping elements and measure growth. Our results point toward at least two modes of casque ontogeny among modern birds: (1) disunited, in which a midline chondrocranial element grows relatively slowly and posteriad to buttresses lateral dermatocranial bones (i.e. cassowaries), and (2) geminal, in which a rapidly growing casque is built from anteriad right‐left dermatocranial constituents only (i.e. Neognathae). These findings suggest that cassowaries are developmental outliers among extant casqued birds and extinct dinosaurs. Counterintuitively, this work identifies modern cassowaries—previously considered hallmark analogs for non‐avian dinosaurs—as poor osteo‐developmental models for studying the deep history of archosaur casque evolution.Support or Funding Information2018 American Association of Anatomists ‐ Visiting Scholarship (Todd L. Green); 2017 National Science Foundation ‐ Major Research Instrumentation Grant (Paul M. Gignac); 2016 Western Interior Paleontological Society ‐ Karl Hirsch Memorial Grant (Todd L. Green); 2015 National Science Foundation ‐ Early‐concept Grant for Exploratory Research (Paul M. Gignac); 2015 National Science Foundation ‐ Division of Environmental Biology (Paul M. Gignac)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Neonatal Ectotympanic Bone Variation among Lorisiforms and Tarsiers
Authors: Fricano Ellen E. I. , Smith Timothy D , DeLeon Valerie B 
Published: June 2021

Ectotympanic bone morphology is a classic characteristic used to differentiate primates and identify fossil affinities, often depicted as either a ring or tube falling along strict phylogenetic lines. Though ectotympanic bone morphology has been frequently cited in academic literature, the way in which this bone lengthens within and across taxa is still not well understood. The lorisiform ectotympanic bone is often characterized as ring‐like and fused to a slightly expanded petrosal bulla, however some authors have suggested that the degree to which the ectotympanic bone contributes to the external auditory meatus may vary within lorisiforms. The ectotympanic of tarsiers is often depicted as slightly elongate, though not as long as catarrhine primates. It is possible, and likely, that the lorisiform ear canal is longer than the lemuriforms though not as long as tarsiers. However, the degree to which the ectotympanic bone contributes to the ear canal has been a subject of some debate. Thus, can ontogeny resolve the questions surrounding the lorisiform and tarsier ectotympanic bones? Across lorisiforms, is the external auditory meatus derived from the petrosal bone, ectotympanic bone, or some combination of the two at birth?To address these questions, three genera of neonatal lorisiforms (Galago senegalensis, Nycticebus pygmaeus, and Loris tardigradus) and one species of tarsier (Tarsius syrichta) were qualitatively analyzed. It was found that in all three lorisiform species, the ectotympanic ring is formed by birth. The elongation of the ectotympanic bone in lorisiforms occurs almost immediately postnatally. The lorisiform and tarsier ectotympanic bones extend laterally as simple tubes, without forming the tubercles that are observed at intermediate stages in catarrhine species. The precise bony makeup of the lorisiform external auditory meatus varies among the genera studied. At birth among Loris and Nycticebus, the ear canal is already elongated but likely incorporates contributions from structures derived from the squamosal and petrous namely the post‐glenoid tubercle and the auditory bulla. The tarsier ectotympanic bone closely resembles the Galago at birth, and we suggest that the tarsier cranial proportions may be an underlying factor in the ultimate lengthening of the bone in this taxon.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Disappearing Enamel and Molars: The Evolution of a Dietary Niche Focused on Gums
Authors: Burrows Anne M , Hartstone‐Rose Adam , Nash Leanne T , Silcox Mary T , Selig Keegan R , López‐Torres Sergi 
Published: June 2021

Gummivory, a diet focused primarily on gums, is a relatively rare dietary niche among mammals, but is found in several species of strepsirrhine primates. Getting gums requires either gouging a wound in tree bark to stimulate gum flow or scraping at a semi‐dried gum plug. Both of these acquisition activities focus on the anterior dentition, and the processing of the gums requires minimal mastication with molars. Primate diets focused on leaves and fruits are associated with specific dental signatures, morphological features that can also be used when examining the fossil record. Does gummivory, a relatively low‐quality diet based on foods that are readily available, have a consistent dental signature among primates? How did the evolutionary process of gummivory in primates shape the dentition, if at all? The present study was designed to evaluate these questions. Linear measurements were collected via calipers from select anterior teeth and the last lower molar from lorisid primates that feed primarily on gums and their closely‐related, non‐gummivorous relatives: Loris spp. (n=19), Nycticebus coucang (n=61), Arctocebus spp. (n=8), and Perodicticus spp. (n=40). Mean scaled differences were compared among the four groups using Bonferroni corrected one‐way ANOVA's (alpha <0.05). For some of these taxa, differential enamel thickness in the lower canine, used to represent the toothcomb, was examined via Micro‐CT scans. We found consistent reduction (p<0.05) of the lower last molar in gummivorous taxa relative to the non‐gummivorous taxa. We also found differential distribution of enamel thickness in the anterior teeth (specifically, the toothcomb) with reduced enamel on the lingual surface relative to the labial surface of the toothcomb teeth. This feature is consistent with the findings from previous studies of other gouging mammals, and gummivorous primates. Together, these dental findings suggest a potential dental signature of gummivory in primates: reduction of the lower last molar and differential distribution of enamel thickness in the anterior teeth.Support or Funding InformationNSERC Discovery Grant and Department of Anthropology, University of Toronto.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Mesenchymal Cells Utilize Integrins to Attach to Titanium Implant Surfaces
Authors: LALLIER THOMAS Edward 
Published: June 2021

ObjectivesTitanium implants have been used for decades to effectively replace missing teeth. Recently, surface modifications have been used to enhance implant osteointegration. Despite these innovations, little is known about how cells interact with modified titanium surfaces. This study aims to examine how mesenchymal cells attached to modified titanium surfaces.MethodsHuman periodontal ligament (PDL) and gingival fibroblasts were evaluated for their ability to survive and attach to three different commercially available implants; Dual thermo‐etched titanium (DTET), hydroxyapatite coated dual transition surface (HADTS) and moderately rough titanium oxide layer with high crystallinity and a high phosphorus content (MRTOP). Subsequently, the cell attachments to modified titanium surfaces were examined for enhancement using serum proteins and inhibition using anti‐integrin as well as anti‐extracellular matrix molecule (ECM) antibodies.ResultsCells attached to modified titanium implant surfaces in a time dependent manner over 24 hours, with no significant difference between the surface modifications examined. Cell attachment was dependent upon the presence of serum in the growth media. Serum is known to contain several ECM proteins, including; fibronection, fibrinogen, and vitronectin. Integrin β1 antibodies significantly inhibited cell attachment, while αVβ3 antibodies did not. Fibronectin/RGD dependent integrin receptor antibodies (αV and α5) inhibited early attachment (before 8 hours). In contrast, collagen dependent integrin receptor antibodies (α1 and α2) inhibited only later attachment (after 8 hours). Finally, laminin dependent integrin receptor antibodies (α3 and α6) failed to significantly inhibit cell attachment. In addition, fibronectin (and to a lesser extent fibrinogen) antibodies inhibited early cell attachment, while collagen Type I antibodies inhibited later attachment.ConclusionsCell attachments to titanium surfaces are at least partially modulated by integrin receptors via ECM proteins coating the titanium surfaces. Cell attachment can be broken down into 2 phases: (1) mediated by serum fibronectin/fibrinogen for the first 8 hours, and (2) mediated by collagens produced by the mesenchymal cells between 8 and 24 hours. Further studies are needed to determine if any of these integrin mediated attachment events effect osteoinduction or osteointegration.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Creating a 3D Model to Study Equine Lameness
Authors: Lee Alexander K. K. , Uhl Elizabeth W. , Osborn Michelle L. 
Published: June 2021

Chronic lamenesses in horses are often managed but not effectively treated. We hypothesize that (1) a causal relationship exists between the forces created by aberrant biomechanical positions and movements, and degenerative joint diseases, and (2) adjusting the aberrant biomechanics will treat the lameness. As a first step in testing our hypotheses, we have constructed a computer model using equine CT data to model full body positions and gaits that may be related to various equine lamenesses. 3D equine bone models were reconstructed from equine CT data obtained from the University of Georgia and Louisiana State University using the 3D visualization and analysis software, Avizo®. The bone models were imported into Autodesk® Maya® for repositioning of the full skeleton. In Autodesk® Maya®, a full 3D rig was attached to the model to allow for accurate positioning and animation. The ribbon spine technique was used on the spine and neck of the model to allow for accurate positioning with the ability to rotate and bend the spine. The rig was adopted to be manipulated using controls for easier and quicker positioning. To create a trot animation using the model, still frames from Muybridge were used as reference; and the model was matched to the positioning in the photos. Once key positions were set, an animation could be rendered. To demonstrate the utility of the model, we used it to compare the habitual standing posture of a horse with a left front anatomical club foot to that of a horse with normal front limb anatomy using photographs taken from different angles. The model demonstrated there were whole body postural effects of the anatomical club foot in that the horse's vertebral column was bent around the limb with the club foot and the pelvis tilted so the opposite hip was slightly raised. The limb with the club foot was also rotated laterally, which further exacerbated the club shape of the hoof by increasing the stress impacting its lateral wall. Identification of these secondary postural affects allowed them to be targeted and effectively resolved through rehabilitative exercises, which greatly diminished the negative impact of the anatomic abnormality. Our future goal is to further expand the usefulness of the model for 3D biomechanical analysis of equine lameness and to develop a protocol for 3D model creation that can be adopted and edited for use in various animal or human studies.Support or Funding InformationLouisiana State University School of Veterinary Medicine Charles V. Cusimano Equine Health Studies ProgramThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Visible Humanity
Authors: Spitzer Victor Michael 
Published: June 2021

The objective of this work is to utilize Visible Human Project type imaging on a donated human cadaver specimen and integrate that image data and resultant anatomical modeling with the medical history and life experience of the donor for the education of medical and healthcare students. The Visible Human Project (1991) was focused on producing three‐dimensional, photographic image data of optimal human anatomy. Criteria for Visible Human specimens required a young donated cadaver with no visible pathology and no surgical interventions. In 2000, a woman presented with a passionate desire to be a “visible human”. It was eventually agreed (after she examined the freezer and cryomacrotome that would be used to section her) that her wish would be granted if the conditions of her death made it possible and if she would also include her medical and life history including video documentation of her remaining life as part of her donation. Motivation for her body and life history donation was to increase compassion among healthcare workers. In contrast to Visible Human Project criteria, she was 72 years old in 2000, had 26 surgeries including four cervical screws with connecting wires to stabilize her cervical vertebrae and a prosthetic hip. She survived melanoma, breast cancer and severe depression. She was sure and determined she would die within a year. She passed away on February 16, 2015. She was imaged with CT and MR and frozen. A plastic copy of her hip prosthesis was 3D printed from the CT data. The hip region was thawed and the prosthetic hip replaced with the plastic copy to permit sectioning the pelvis. The cervical screws and wires were not removed and were successfully sectioned. The cadaver was blocked into four subunits, each less than 20” in height in a manner similar to the Visible Human. Each block was embedded in polyvinyl alcohol dyed blue. Photographic images with 7,360 × 4,912 pixels (pixel size = 63 microns) were acquired in Nikon raw image format. Data includes over 20,000 transverse cross‐sectional photographs, CT and MR images, medical records and hours of recorded video of her life from 2002 till her death. She was introduced to participants at the Fourth Visible Human Conference in Keystone Colorado, October 17–19, 2002. At that conference, some participants participated in videotaped interviews with the donor.Segmentation of the photographic images has begun and 3D models of her aged vasculature reveal their tortuosity and pathology. 4K and HD videos of the cross‐sectional photographs have been rendered and will be available for viewing. CT renderings of the whole body and the cervical vertebral fusion will also be presented. This is NOT part of the Visible Human Project and that was made clear to the donor prior to herSupport or Funding InformationFunding provided by Touch of Life Technologies, Inc. and the University of Colorado Department of Cell and Developmental Biology.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The “Avocado Lab:” an inquiry‐based laboratory experiment to interrogate the function of polyphenol oxidase in avocado browning
Authors: Peres Shelby , Riley Kasandra 
Published: June 2021

In the presence of oxygen, polyphenol oxidases (PPO) catalyze oxidation of phenolic compounds into quinones, the polymerization of which is responsible for the visible browning of cut fruits. PPOs are expressed in diverse organisms including animals, fungi, and plants, and the avocado fruit provides students a unique vehicle for qualitatively exploring this enzymatic reaction. Here, we present a scalable, inquiry‐based laboratory experience that is tunable for non‐science undergraduates to 300‐level biochemistry students. Students are provided with a single Haas avocado and access to an assortment of common laboratory and household reagents including salts, oils, soaps, EDTA, reducing reagents, onions, sugar, acids/bases, etc., as well as the ability to control temperature, light, or exposure to air. Each student designs a well‐controlled experiment to test a hypothesis regarding the effect of one or two variables on avocado browning in a two to three‐hour span. During the incubation time, biochemistry students use the Protein Data Bank and primary literature to better understand the structure of PPO and other molecular components of the avocado, while non‐major students discuss the roles of pH, temperature, and substrate availability on an enzyme. Due to the inherent complexity of fruit flesh, avocado browning is not completely understood and is likely multi‐faceted, leading to opportunities for discussion in both classrooms. The insoluble brown phytomelanins produced in the browning reaction appear on a controllable time scale and are easily depicted in a color photo, so students can create a figure to accompany a qualitative analysis of their experimental results in a single lab period. Furthermore, since avocados are familiar foods and select test reagents are generally recognized as safe, the optimal protocol investigated in the lab can be further applied to best practices in the kitchen in everyday life, promoting the transfer of knowledge learned in the classroom to practical environments.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.