bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasability of osseous landmarks for reconstruction of the anterior cruciate ligament ő comparison experts and beginners (914.7)
Authors: Hirtler Lena , Rieschl Domink , Lübbers Anke , Weninger Patrick
Published: June 2021

BACKGROUND: During knee joint arthroscopy an easy orientation is important to achieve an anatomical correct reconstruction. The lateral intercondylar ridge (LIR) as well as the lateral bifurcate ridge (LBR) were described in literature as possible landmarks to find the location for the femoral tunnel placement.

The objective of this trial was, to show the feasibility of the LIR and the LBR as landmarks of the femoral attachment of the ACL in all levels of specialization.

METHODS: 36 formalin‐phenol‐fixed lower extremities from donations to the anatomical institute were required for this study. All soft tissue, apart from the knee ligament, was removed. The two bundles of the ACL were identified and marked. Afterwards, also the ACL was removed and the origin of the two bundles was marked and photographed. The bone of the intercondylar fossa was exposed and again photographs were taken. All photographs were made in a standardized setting. Using these photographs a trauma surgeon, an anatomist and a medical student had to identify and mark the ridges if discernible.

RESULTS: There was a significant difference between the markings of the medical student on the one side and the trauma surgeon resp. the anatomist on the other side.

CONCLUSIONS: This trial shows the feasibility of the LBR and LIR as osseous landmarks during arthroscopic surgery of the knee. As these ridges are not easily discernible, the surgeon has to know the anatomy of the intercondylar notch perfectly to stand even a small chance in correctly placing the drill hole in ACL reconstruction. For beginners in arthroscopic surgery, easier identifiably landmarks have to be introduced.
Anatomic study of the volar surface of the distal radius (915.3)
Authors: Barros Mirna , Costa Antonio , Barros Marcos Felipe , Chakkour Ivan
Published: June 2021

Purpose: Analyze the anatomy of the the volar surface of the distal radius.Methods: We have studied 54 radiuses with Contour Gauge (General®, nº 337, USA) the volar surface of the radius in three planes: a)longitudinal, medium point of the volar surface of the distal radius; b)transversal, medial surface, perpendicular to the radius’ long axis and c)parallel to the joint, distant 5 mm from it. We have measured the inclination of distal radius on the volar and lateral planes,the morphology of the volar surface through the angle between the diaphysis and the watershed line(a);distance between the beginning of the protuberance and the watershed line(A);distance between the watershed line and the joint(B);distance from the protuberance beginning to the joint(C) and the height of volar portion(D). We have classified the contours into four types: Type I‐plain, with sudden inclination in the radial half; Type II ‐concave; Type III‐convex and Type IV‐plain.

Results: The inclination angle (a) varied from 12o to 26o, average 19.81o ± 3.40º. The A value varied from 11.53mm to 33.12mm, average 19.54mm ± 4.98mm; the B value varied from 3.02mm to 7.40mm, average 4.74mm ± 0.85mm; the C value varied from 16.29mm to 39.19mm, average 24.29mm ± 5.13mm; and the D value varied from 4.42mm to 9.21mm, average 6.75mm ± 1.05mm. The contours classification in the long radius axis perpendicular plane were: 11 Type I, 17 Type II, 14 Type III and 12 Type IV. Parallel to the joint, 19 were Type I, 12 Type II, 11 Type III and 12 Type IV.Conclusion: The morphology of the radius volar surface was variable, and the study helped in the comprehension of the anatomy.
A unique case of bilateral sciatic nerve variation within the gluteal compartment (915.9)
Authors: Butz James , Raman Daya
Published: June 2021

In the course of routine cadaver dissection, variants in the emergence of the sciatic nerve (SN) from the pelvis to the gluteal compartment were discovered bilaterally. Meticulous dissection was used to isolate and visualize the SN via lateral reflection of the gluteus maximus showing the SN and its variants described herein. In the left gluteal region, the SN had a high division where the fibular division exited the pelvis superior to the piriformis muscle while the tibial division exited inferior to the piriformis. Additionally, in the right gluteal region, the fibular division was observed to have split the piriformis muscle before it joined the tibial division of the SN which exited the pelvis inferior to the piriformis muscle. An abnormal pathway of a nerve’s course emerging through or around a muscle may yield dual or anomalous innervation of a muscle. As it applies to this case, speculation may be placed on the patient’s piriformis and gluteus maximus muscles receiving variant innervation by the SN or a division of that nerve. Further, if inappropriately trapped within the confines of a muscle or regular boundaries, variant emergence of a nerve could give rise to distal neuropathy. As was seen in this case the patients right piriformis muscle, having been split by the SN, appears atrophied in comparison to the patients left piriformis muscle, which was entrapped by fibular and tibial divisions of the SN.
Case report of a giant hepatic cyst observed during routine dissection in gross anatomy lab (916.3)
Authors: Siu Maggie , Khey Beldman Heather , Chang He , Garach Mehul , Moldovan Nataliya , Yu Bobby , Farias Anna
Published: June 2021

Introduction: Most hepatic cysts are asymptomatic and found incidentally. Giant cysts (>= 6cm across) are likely to be symptomatic and lead to complications such as hemorrhage, rupture, infection, and biliary tree obstruction. Liver cysts are found in 1% of autopsies, but there are currently no cited reports of giant hepatic cysts in cadavers.

Case report: The hepatic cyst was found during routine abdominal dissection for an undergraduate medical class. The donor was an 83 year old Caucasian female with failure of respiratory, renal, and cardiac systems. On inspection, the liver was markedly enlarged with the inferior border of the right lobe surpassing the costal margin. The consistency of the left lobe was spongy, while the right lobe was unremarkable. Removal of the liver resulted in rupture of the cyst and release of its viscous, purulent, and malodorous contents.

Measurements: On gross examination, the liver was measured to be about 20cm at the mid‐clavicular line (normal averages 7cm), while the cyst is approximately 13cm in diameter. We will present a reconstruction of the cyst.

Conclusion: It can be hypothesized that the cyst was previously detected but treatment was withheld due to the patient’s various comorbidities.
Frequency and evolutionary importance of human palatal pneumatization (918.13)
Authors: Swerdloff Daniel , Pagano Anthony , Delman Bradley , Adar Tony , Lawson William , Marquez Samuel
Published: June 2021

Pneumatization of the human hard palate is rare but, when present, occurs via maxillary sinus expansion. Emil Zuckerkandl, the father of sinus anatomy, was the first to document this condition in 1892, illustrating a clear communication between maxillary sinus and hard palate. Later studies have given frequencies of less than 5% with a slightly greater commonality among females. Still others have described palatal pneumatization among a range of non‐human animals including our closest living relative, the chimpanzee. This study examined CT scans from 200 human heads to quantify the frequency of palatal pneumatization and assess for relationships with variables of age, sex, and ancestry. Results showed that only two individuals exhibited palatal pneumatization. One was a European female and the other an Indian male, both aged 20‐40 years. Thus palatal pneumatization occurred at a rate of 1% in our sample with no observable relationship with sex or ancestry. Conversely, most chimpanzee crania exhibited extensive palatal pneumatization, a potential consequence of greater robusticity of the masticatory apparatus. Other non‐primate animals such as deer and mountain goats also exhibited extensive palatal pneumatization, which are apparently homoplastic. Nonetheless, the expression of a pneumatized hard palate among chimpanzees and humans may be a shared derived character inherited from a common ancestor approximately 6.5 million years ago.
Interspecific comparison of ontegenetic change in temporal bone pneumatization (918.22)
Authors: Hill Cheryl
Published: June 2021

Comparative studies of temporal bone pneumatization in adult chimpanzees and modern humans have shown that human temporal bones have reduced pneumatization compared to chimpanzee temporal bones, following the general trend towards reduction in pneumatization over the course of hominid evolution. Although the adult pattern of pneumatization in chimpanzees is well studied, extensive quantitative comparisons of the ontogenetic change in pneumatization of the temporal bone in chimpanzees and modern humans have not been completed. The purpose of this study is to compare patterns of ontogenetic change in temporal bone pneumatization in humans and chimpanzees.

High resolution computed tomography scans were acquired from cross‐sectional ontogenetic series of human (n=29) and chimpanzee (n =30) temporal bones. The sample included individuals ranging in age from neonate to adult for both species. Surface areas and volumes of the temporal bone air cell tracts were calculated using Amira for both species.

Results indicate that, from an early age, chimpanzees show larger surface areas and volumes of the temporal bone air cell tracts compared to modern humans. Although there are some differences in timing of pneumatization in the two species, these differences in size may result from the progression of the air cells from both the mastoid and squamous antrums in chimpanzees. This study highlights the early establishment of adult size differences in pneumatization.
The ontogeny of sexual dimorphism in the skull of the springbok antelope (Antidorcas marsupialis) (918.7)
Authors: Brakora Katherine
Published: June 2021

Antelope (Artiodactyla: Bovidae) provide many classic examples of sexual dimorphism, but the ontogenetic pathway to adult sexual dimorphism has not been systematically studied. Moreover, it is unknown whether the development of obvious sexual differences in horn size correlate with the development of sexual differences in other horn traits, skull size, or skull shape. To better understand springbok skull development in general, and the development of sexual dimorphism in particular, I compared skulls from more than 50 springbok (Antidorcas marsupialis), which had been harvested, sexed and age‐estimated from a wild population in northern Namibia from 1992‐1994, and ranged from 7 months to >5 years old. Seven traits were examined: horn length, circumference, and number of horn rings, and skull size and shape in ventral and lateral views. Skulls were photographed in ventral and lateral views, landmarks were digitized, and 2D geometric morphometric analysis was performed using standard software and procedures. For each trait, male and female values were compared in yearlings and in adults to test the hypothesis that springbok sexual dimorphism increases after one year of age. By one year of age, males were significantly larger than females in horn length, horn circumference, and the sexes differed significantly in lateral skull shape. After one year of age, sexual differences increase in horn circumference and lateral skull size, and decrease and then reverse in the number of horn rings. Sexual differences were observed in nearly all trait studied. However, sexual differences arose at various times for the different traits. Whether these differences increased, were maintained, or reversed with age also depended on the trait. The developmental timing of sexual differences in size and shape indicates that sex‐specific changes in skull shape, and not allometry through male growth, are the primary mechanism for achieving sexual differences in skull shape.

Grant Funding Source: Supported by an NSF‐GRF pre‐doctoral fellowship.
Effects of the propylthiouracil on tooth development in newts (921.3)
Authors: Miwa Yoko , Sunohara Masataka , Shimada Kazuyuki , Sato Iwao
Published: June 2021

Objective: Propylthiouracil (PTU) is originally a thiouracil‐derived drug used to treat hyperthyroidism by blocking the effect of thyroid hormone. Recently, PTU is using as a marker of pollutant as a potential thyroid hormone disruptor in aquatic environments. The purpose of this study was to evaluate the effects of exposure to PTU on the development of the teeth and the regeneration of alveolar bone following amputation.

Method: Japanese newts (Cynops pyrrhogaster) were maintained in aqueous solutions with or without 100 ug/ml PTU for one month and tracked the sequential development of the tooth cap, the tooth bud, and ultimately the maturation of the sequential tooth germ. Fifty days after the amputation procedure of the right mandible alveolar bone, the newts were observed the effect of PTU by the expression levels of mRNA of thyroid hormone receptor detected in‐situ hybridization. A microscope and digital camera interfaced with Image Analysis & Measurement Software WinROOF (Mitani Corp., Japan) were used to measure the areas of regenerated alveolar bone.

Result: The amputated mandible sites were observed microscopically. The regenerated area of alveolar bone in amputation with PTU treatment was significantly smaller than that in the amputation without PTU treatment (Student’s t‐test, p<0.001). There were no differences in the bone histology and tooth germ generation with or without PTU.

Conclusion: These data indicate that PTU may affect the tooth germ development and the regeneration of alveolar bone in newts.
Developmental origins of the stomodeum links brain and jaw size evolution (921.8)
Authors: Fish Jennifer , Schneider Richard
Published: June 2021

The evolutionary relationship between brain size and jaw size has been explored in many Vertebrate clades, and is particularly relevant to studies of human evolution. In hominins, an increase in brain size is associated with smaller jaws, but the degree to which these evolutionary changes are independent is largely unknown. We have used quail and duck, two embryos with remarkably different jaw size, to investigate the early developmental relationship between brain and jaw size. Species‐specific jaw size in quail and duck is associated with corresponding differences in early developmental head patterning, including differences in brain regionalization and the size of the stomodeum, or primary mouth. At HH13, the stomodeum in duck is long and narrow, whereas the stomodeum in quail is shorter and rounder. Neural crest migration in quck embryos indicates that stomodeum morphology affects the number of neural crest migrating into the region around the stomodeum, which subsequently determines the initial size of the jaw primordia. To investigate the molecular origins of the distinct head morphology in duck and quail embryos, we investigated the expression of early neural plate and brain regionalization genes, including Pitx2, Pax6, Otx2, Fgf8, Shh, and Krox20. We find that duck embryos exhibit an anterior shift in head patterning at neural plate stages, which increases the length between the midbrain and the primitive foregut in duck relative to quail. Our data suggest that species‐specific differences in jaw size are mediated, in part, by very early developmental mechanisms establishing brain regionalization.

Grant Funding Source: Supported by NIH NIDCR R01 DE016402 and F32 DE021929
Effectiveness of diode laser 904nm in the regeneration of bone defects in diabetic rats (922.17)
Authors: Silva Jairo , Fazan Valéria Paula , Pardini Luís , Thomazini José
Published: June 2021

The acceleration of bone formation in the repair of large bone defects is a major challenge in health science. Diabetes Mellitus is a chronic metabolic syndrome that causes decreased blood flow and consequently interferes negatively on the consolidation time of bone defects. Therapy with low intensity laser has shown efficiency in cellular regeneration and can influence immune and inflammatory responses that play an important role on bone tissue the regeneration. This study aims to evaluate the efficacy of 904nm laser diode in the regeneration of bone tissue to repair a bone defect in diabetic rats. Forty male Wistar rats were divided into 4 groups: Group 1, control, not diabetic and without laser treatment; Group 2, diabetic animals, induced by a single venous injection of streptozotocin (STZ) (40mg/Kg) without laser treatment; Group 3, diabetic animals treated with laser dose 60w 4J/cm for 17s every other day, for 14 days; Group 4, diabetic animals treated with laser dose 120w 4J/cm for 17s every other day, for 14 days. Bone defect was induced with a 2 mm drill on the left tibia and different groups were evaluated by X‐ray and bone densitometry. Our results show that the laser diode 904nm is enhancing bone repair in diabetic rats. Further histopathological evaluations will confirm these findings.

Grant Funding Source: FAPESP, CNPq and FAEPA
V‐ATPase‐mediated secretion and activation of cathepsins in breast cancer cells: investigating the role of vacuolar H+‐ATPases subunit A isoforms in breast cancer metastasis (934.4)
Authors: Hinton Ayana
Published: June 2021

V‐ATPases are multi‐subunit H+ pumps that acidify intracellular compartments and are essential for bone degradation synaptic signaling, etc. They are at the cell surface of the highly metastatic breast cancer cell line MDA‐MB231, and may contribute to its metastatic phenotype. We hypothesize that V‐ATPases create a low pH environment that promotes tumor cell invasion by activating secreted cathepsins. Cathepsins cleave extracellular matrix proteins and activate other proteases, facilitating local tumor invasion. We are studying the role of subunit a isoforms in secretion and activation of cathepsin B and L. The 4 subunit a isoforms are responsible for cellular localization of V‐ATPases. Treatment with concanamycin A (a general V‐ATPase inhibitor) affects the activity of intracellular and secreted cathepsins B and L. Concanamycin A treamtment also affects the secretion of cathepsins B and L. siRNAs were used to reduce mRNA expression of each subunit a isoform. We have previously shown that knockdown of the a4 isoform decreased the level of processed cathepsin L in conditioned media, but not the unprocessed form. Our previous findings also indicate a4 targets V‐ATPases to the cell surface, thus we hypothesize that the a4 isoform will have the largest effect on secretion and activation of cathepsin B and/or L. Following isoform‐specific knockdown, immunoblotting and cathepsin activity assays are being used to analyze cathepsin B and L expression and activity in conditioned media and cell lysates of MB231 cells. This study increases our understanding of the role V‐ATPases are playing in the activation of secreted cathepsins in the tumor microenvironment of MB231 cells.

Grant Funding Source: Funded by Denison University Anderson Fellowship
Epigenetic deregulation of Bcl‐2 leads to apoptosis resistance in melanoma (942.2)
Authors: Sengupta Deepanwita , Avaritt Nathan , Tackett Alan
Published: June 2021

Aberrant activity of the histone methyltransferase enhancer of zeste homolog 2 (EZH2) has been reported to be associated with different types of cancer. One of the major characteristics of cancer is unregulated cellular proliferation and evasion of apoptosis. Over the years, independent studies by different laboratories have reported the involvement of EZH2 in cell proliferation and apoptosis resistance in different types of cancer. Yet a detailed mechanism of EZH2‐mediated resistance to apoptosis in cancer is still lacking. One of the goals of our laboratory is to determine the contribution of EZH2 to evasion of apoptosis in advanced stages of melanoma. We have performed proliferation assays and annexin V/propidium iodide staining, which indicate increased proliferation and reduced apoptosis in late melanoma. Our studies also indicate presence of increased mRNA and protein levels of the anti‐apoptotic protein Bcl‐2 in metastatic melanoma. Chromatin immunoprecipitation performed with antibodies specific to EZH2 and trimethylated lysine 27 on histone H3 (H3K27me3) followed by quantitative PCR have shown higher EZH2 and H3K27me3 (silencing mark) enrichment in BCL‐2 promoter in melanoma cell line WM115 (isolated from a primary tumor) compared to matched melanoma cell line WM266‐4 (isolated from subsequent metastasis in the same patient). All these results suggest that reduced binding of EZH2 to BCL‐2 promoter in metastatic melanoma results in reduced silencing of Bcl‐2 that ultimately contributes to apoptosis resistance in advanced stages of the disease.

Grant Funding Source: NIH/NCI R33CA173264 (Tackett, PI), and NIH/NIGMS R01GM106024 (Tackett, PI)
The effect of the estrogenic compounds E2 and BPA on the expression of histone modifying enzymes in two prostate cancer models (942.4)
Authors: Burton Kevin , Bajdas Alicia , Shaw Lisa , Morey Lisa
Published: June 2021

Prostate cancer is the most common form of cancer for males and it has been shown that exposure to estrogenic compounds can increase the likelihood of developing prostate cancer. The goal of this study is to determine the effect of physiological doses of two estrogenic compounds, estradiol (E2) and bisphenol A (BPA), on the expression of histone modifying enzymes (HMEs) in prostate cancer cells. Alterations to the expression of HMEs could potentially lead to global changes in gene expression that may play an important role in the development of prostate cancer due to increased exposure to E2 or BPA. To determine the role of these estrogenic compounds in prostate cancer, two prostate cancer cell lines, LNCaP and PC3, were treated with E2 or BPA alone or in combination with ICI, an estrogen receptor antagonist. All treatments were carried out using physiological conditions. We then isolated RNA from the cells and analyzed changes in mRNA expression of SIRT1, a histone deacetylase, and SET8, a histone methyltransferase, using semi‐quantitative RT‐PCR. The results of our experiments show that the expression of the two HMEs being studied was altered by treatment with E2 or BPA alone as well as in combination with the ICI. We also observed different changes in gene expression of the HMEs between the two cell lines. These results indicate that the estrogenic compounds E2 and BPA do affect the expression of HMEs in two different prostate cancer models, and therefore demonstrate a complex effect in prostate cancer.
Programming of phosphoenolpyruvate carboxykinase by maternal high fat diet may contribute to hepatic fat accumulation in female offspring rats (942.6)
Authors: Cui Hemiao , Zhou Dan , Chen Hong , Pan Yuan‐Xiang
Published: June 2021

Phosphoenolpyruvate carboxykinase (PEPCK) produces phosphoenolpyruvate during glyceroneogenesis. We previously demonstrated that high fat diet during pregnancy induced PEPCK mRNA expression in neonatal pups, which is characterized by histone modifications in specific regions of the gene. In the present study, we investigated persistency of the alterations in adult offspring. Dams were fed either control or high fat diet throughout gestation and lactation. Offspring were placed on control diet after weaning, generating C/C and HF/C groups. Liver was collected at 12 wks of age. Hepatic NADH level was increased in both genders but fat accumulation occurred only in female liver (HF/C). This was accompanied by a significant increase of PEPCK and Fatty Acid Synthase (FASN) mRNA expression in female liver. The induction of PEPCK gene expression was associated with an increased dimethylated histone H3 lysine 4 level in multiple regions of the gene. Meanwhile, trimethylated histone H3 lysine 4 was induced at a specific coding region in HF/C, accompanied by a decreased trimethylated histone H3 lysine 9 level at the promoter. In conclusion, maternal high fat diet programs PEPCK expression through histone modifications in adult offspring. Persistent PEPCK induction contributes to triglyceride synthesis. Combined with induced FASN and NADH, this leads to increased fat deposition in a gender‐specific manner.
Roles of sphingolipid metabolism in non‐alcoholic fatty liver disease (96.1)
Authors: Geng Tuoyu , Sutter Alton , Chavin Kenneth , Cowart L
Published: June 2021

Non‐alcoholic fatty liver disease (NAFLD) comprises hepatic steatosis that often progresses to inflammation and ultimately cirrhosis, hepatocellular carcinoma, and subsequent need for transplant. Mechanisms mediating the NAFLD are of major clinical interest. Epidemiological studies in humans have linked consumption of dietary saturated fat to NAFLD severity. Because we have previously demonstrated that saturated fatty acids increase transcription of sphingosine kinase 1 (SphK1), and known roles of SphK1 in recruitment of inflammatory cells, we hypothesized that SphK1 may contribute to NAFLD progression. Our data indicate that SphK1 message increases in both mouse and human progressive NAFLD, and SphK1‐null animals demonstrated protection from NAFLD. Saturated fatty acids induced SphK1 in hepatocytes, and treating hepatocytes with the SphK1 product, sphingosine‐1‐phosphate (S1P), increased inflammatory signaling in a manner dependent on S1P receptors. These data implicate the SphK1/S1P axis in progression of liver disease arising from obesity and/or dietary saturated fat and suggest the potential of therapeutic targeting of this axis in NAFLD treatment.
Isolation and characterization of a novel class of potent anti‐HIV proteins from an Australian soft coral (975.6)
Authors: Ramessar Koreen , Xiong Chang , Krumpe Lauren , Buckheit Robert , Wilson Jennifer , McMahon James , O'Keefe Barry
Published: June 2021

An estimated 34 million people are living with the human immunodeficiency virus (HIV) worldwide. Increasing resistance to antiretrovirals (ARVs) challenges current therapies and it is critical to identify novel non‐ARV anti‐HIV agents to prevent infection. Here we report the isolation of a novel class of proteins, called Cnidarins, from the soft coral Synthecium sp. (phylum Cnidaria). The proteins were purified by sequential ethanol and ammonium sulphate precipitation followed by hydrophobic interaction chromatography. The purified proteins, CNID‐1, CNID‐2 and CNID‐3, were monomers of ~170 amino acids with molecular weights of ~18 kDa. CNID‐1 and CNID‐3 (fully sequenced) showed no significant homology (>25%) to any known protein. All three cnidarins showed picomolar to low‐nanomolar activity against laboratory strains and primary isolates of HIV‐1. They inhibited viral fusion in a concentration‐dependant manner but not viral attachment, indicating the proteins’ antiviral effects occur after initial virus‐to‐cell attachment but prior to viral entry. CNID‐1 was the most potent (EC50 of 85 pM) and bound to viral glycoproteins gp120 and gp41 equally in a concentration‐dependant manner, but not to other glycoproteins or soluble CD4. Pre‐treatment with CNID‐1 did not block sCD4 binding to gp120 and vice versa and its gp120 binding was independent of glycosylation. Pre‐treatment with other potent antiviral proteins, cyanovirin and scytovirin, did not affect CNID‐1 binding to gp120 and gp41, and seemed to promote slightly better binding of CNID‐1, while griffithsin pre‐treatment reduced CNID‐1 binding but not completely. Recombinant production in E.coli resulted in C‐terminal truncated forms of CNID‐1 (14‐16kDa, EC50 of 45‐150nM). Ongoing work includes optimizing expression conditions to produce fully active rCNID‐1. Cnidarins represent a novel class of proteins that target viral fusion and inhibit HIV infection in a manner different from any currently identified anti‐HIV agent.

Grant Funding Source: Supported by the Intramural Research Program, National Cancer Institute
Investigation of the interaction between human cathelicidin LL‐37 and CpG DNA (978.2)
Authors: Radford Michelle , Avelsgard Irmamarie , Craig Maria
Published: June 2021

The human cathelicidin LL‐37, an antimicrobial peptide of innate immunity, forms complexes with extracellular DNA and transports DNA across cell membranes. Complex formation between LL‐37 and DNA is the first in a series of events that upregulate an autoimmune response to self‐DNA. In order to characterize LL‐37/DNA binding, we have performed electrophoretic mobility shift assays (EMSA), western blotting, and isothermal titration calorimetry (ITC). By EMSA, we observe a shift in DNA mobility with increasing LL‐37 concentration over the range 5‐50 uM, and quantitative analysis of gel images was performed to derive binding curves for the association of LL‐37 with DNA. Western blots in this concentration range indicate that LL‐37 self‐associates in the absence of DNA, forming complexes that increase in size as LL‐37 concentration increases. These LL‐37 self‐complexes decrease in size in the presence of DNA. The ITC results support a two‐site model for LL‐37/DNA association with a 20:1 peptide: DNA ratio and association binding constants on the order of 108 to 109 M‐1. These data suggest that LL‐37 self‐associates at concentrations sufficient to bind DNA, and that DNA binding to LL‐37 displaces LL‐37 self ‐contacts. This mode of binding may allow efficient incorporation of DNA into complexes at LL‐37 concentrations above a specific threshold level. This work was supported by the Mary Baldwin College Summer Research Fellows Program.
Post‐translational modifications of host proteins in pathogen defense (98.3)
Authors: Xavier Ramnik
Published: June 2021

Autophagy is a cellular disposal system that directs cytoplasmic cargo into lysosomes for proteolytic degradation. In addition to recycling biomass such as organelles, autophagy serves to capture and kill intracellular pathogens, thus representing a central mechanism of host defense that is evolutionarily conserved from plants to mammals, emerging evidence highlights the critical role of autophagy in host defense against a broad range of bacteria, which collectively represent one of the most medically important groups of human pathogens. Understanding how cells select and sort pathogens into the autophagic pathway without destroying important cellular components is a major question in the field. Using integrative genomics, we have previously identified FNBP1L (formin binding protein 1‐like) and LRSAM1 as essential for autophagy of S. Typhimurium. FNBP1L contains an F‐BAR domain, which is typically involved in membrane bending and linking membranes with the cytoskeleton. Although FNBPL1 is dispensable for classical forms of autophagy induced by serum starvation or rapamycin, FNBP1L expression serves to restrict the growth of S. Typhimurium through the antibacterial autophagy pathway. LRSAM1 functions as a human antibacterial sensor protein that both interacts with autophagic machinery and mediates target selection for antibacterial autophagy. LRSAM1 is a target‐specific E3 ligase responsible for the ubiquitination of intracellular S. Typhimurium and thus meditates a key step in the induction of the major anti‐Salmonella autophagy pathway. We will present data based on screening >3000 candidate genes in the autophagic response to S. Typhimurium. The initial set was selected based on their identification as: (1) common genetic variants associated with Crohn’s disease and ulcerative colitis; (2) genes associated with the selective autophagic targeting of viruses/bacteria; (3) E3 ubiquitin ligases; and (4) genes identified through proteomic protein‐protein interaction analysis as key regulators of the autophagy network
Functional genomic elucidation of nicotinic acid catabolism in Bacillus niacini towards a metabolic engineering approach to environmental remediation (980.2)
Authors: Harvey Zachary , Snider Mark
Published: June 2021

N‐heterocyclic aromatic compounds, particularly those used as pharmaceuticals and herbicides, constitute environmental contaminants of emerging concern due to their water solubility and carcinogenicity. Metabolic engineering could yield a biotechnological solution to this problem, and thus we investigate the functional genomics of Bacillus niacnini with regard to nicotinic acid (vitamin B3) catabolism. Such metabolism is poorly understood in phyla beyond protobacteria, and thus the identification of the genes responsible for this phenotype could suggest an evolutionary origin for such chemistry and provide new “parts” for the previously described remediation framework. Nicotinic acid catabolism‐relevant genes were identified first by the whole genome sequencing of B. niacini using the Illumina platform, followed by bioinformatics using de Bruijn graphs as part of the Velvet package. Following annotation and function predictions based on position‐specific iterated basic logical alignment searches, predicted genes were confirmed using RT‐PCR.
A Model Interaction for Structural Biology and Health Research: Implications of the Antibody D25 bound to the RSV Pre‐Fusion Glycoprotein (LB100)
Authors: Cheranov Maksim , Eaton Muriel , Hattemer Mark , McClain Amy , Rajendiran Pranav , Rana Riya , Saripalli Nithin , Singh Jai , Yang Louise , Kessler Eric , Tuel Kelley , Whalen Joseph , Graham Barney , McLellan Jason
Published: June 2021

Respiratory syncytial virus (RSV) is a paramyxovirus that infects all infants by age 3 and causes extensive morbidity, hospitalization, and global mortality in young infants. RSV F is a type I fusion glycoprotein essential for viral entry into cells, and exists as a trimer of heterodimers. Furin cleavage produces F1 and F2 subunits and exposes the hydrophobic fusion peptide which is buried at the base of the cavity formed by the prefusion trimer. An unknown triggering event causes a major conformational rearrangement producing a 10 Å heptad repeat (HR) with fusion peptide exposed on the distal end positioned to pierce the target cell membrane. The C‐terminus HR anchored in the viral membrane then swings around to approximate the N‐terminus HR resulting in an anti‐parallel 6‐helix bundle pulling the virus and cell membranes together to mediate fusion and allow viral entry. The Blue Valley CAPS SMART (Students Modeling a Research Topic) Team modeled RSV F in complex with the human antibody D25 using JMol and 3D printing technology. D25 binds antigenic site Ø locking the protein in its prefusion state. The stabilized prefusion trimer has been shown to elicit antibodies to antigenic site Ø with potent neutralizing activity. Thus, solving the atomic structure of the prefusion RSV F facilitated development of a candidate vaccine now being produced for evaluation in clinical trials.

Grant Funding Source: Supported by grants from the NIH‐SEPA and NIH‐CTSA.
Calorie restriction promotes genome stability in mismatch repair defected cells during aging (LB118)
Authors: Lo Yi‐Chen , Chang Jia‐Chi , Teong Xiao Tong , Lo Yun‐Jun , Leow Siew‐Keng , Kao Cheng‐Fu
Published: June 2021

Mismatch repair is a DNA repair system which is critical for the maintenance of genome stability. Defects in mismatch repair have been linked to colorectal and sporadic cancers. Calorie restriction (CR) has been shown to extend life span in various organisms and reduce tumor incidence in mammals. By using Saccharomyces cerevisiae model system for CR and aging studies, mismatch repair defective cells (msh2Δ, msh3Δ, msh6Δ, msh2Δmsh3Δ, msh2Δmsh6Δ and msh3Δmsh6Δ) were cultured with normal (2% glucose) and CR (0.5% glucose) medium. Here we demonstrate that CR containing 0.5% glucose compared to normal treatment (2.0% glucose) can extend life span and promote HOM3 gene stability in all MMR‐defected cells during aging process in yeast. Although the levels of reactive oxygen species (ROS) were significantly increased during aging and CR dramatically reduce the levels of ROS, the levels of ROS had no positive correlation with HOM3 gene mutation rates by comparing those in wild type cells and MMR‐defected cells. The underlying mechanisms need to be further investigated.
Functional Identification of DNA Methylation Patterns of Tumor Suppressor Genes in Cancer (LB127)
Authors: Akinhanmi Margaret
Published: June 2021

Promoter hypermethylation is a well‐studied epigenetic modification that regulates gene expression. During tumorigenesis, hypermethylation of the entire CpG‐rich region (CpG island) at the promoter of tumor suppressor genes can silence gene expression and lead to cell proliferation. However, analyses of clinical genomic data rarely find hypermethylation at the entire promoter. DNA methyltransferase inhibitors (DNMTis) have been successfully used therapeutically on the basis that they reverse this hypermethylation effect but it is unclear which partial changes affect gene silencing and thus which patients can benefit from these targeted therapies. We seek to pinpoint individual CpGs that contribute to gene silencing using the promoter region of a known tumor suppressor gene, cyclin‐dependent kinase inhibitor 2A (CDKN2A). We generated a library of CDKN2A promoter sequences with random CpG methylation. The library is then used with a cell reporter system to separate methylation patterns that lead to gene silencing from those that lead to expression. Using highly parallelized bisulfite sequencing, we have pinpointed methylation events at individual CpG sites that contribute to gene silencing. Our analysis will advance our understanding DNA methylation's role in gene regulation. Furthermore, pinpointing functional promoter hypermethylation patterns could improve identification of patients that benefit from DNMTis.
Development of new tools for detection and quantification of the infectious hematopoietic necrosis virus (IHNV) in a zebrafish model of infection (LB146)
Authors: Gonzalez‐Montalban Nuria , Mancini Justin , Feng Chiguang , Ravindran Chinnarajan , Keys Robin , Vasta Gerardo
Published: June 2021

Galectins are a conserved family of carbohydrate‐binding proteins involved in a wide variety of cellular processes, such as cell‐cell interactions, tumor proliferation and metastasis, regulation of innate and adaptive immune responses, and recognition of microbial pathogens. Based on distinctive structural features, galectins are classified into the “proto”, “chimera” and “tandem‐repeat” types. Our prior studies have shown that all three categories are expressed in zebrafish (Danio rerio), and suggested that DrGal1, DrGal3 and DrGal9 play a key role during experimental infection of zebrafish cell lines with infectious hematopoietic necrosis virus (IHNV). IHNV, an economically important pathogen of both wild and farmed salmonids, is a negative‐sense single‐stranded virus belonging to the genus Novirhabdovirus. The lack of standardized tools for the rigorous detection and quantification of IHNV viral particles in vitro, and commercial antibodies for use in standard immunoassays has seriously hindered progress toward the resolution of this problem. Thus, the development of tools and techniques that will enable the optimization of the IHNV‐zebrafish infection model for the mechanistic study of the IHNV infection process and the subsequent host immune response is of great interest. In this study, we designed a protocol for production and purification of the viral G (glycoprotein) protein of IHNV in recombinant bacteria, and initiated the production of polyclonal antibodies, that will enable us to visualize potential interactions between galectins and IHNV particles.

Grant Funding Source: Supported by grant 5R01GM070589‐06 from the National Institutes of Health to GRV, and the Department of Biotechnology, New Delhi, India, to CR; NGM is supported by grant 5T32AI095190‐02; RK is supported by the ExPERT Program from the NSF
Monocyte chemotactic protein induced protein 1 (MCPIP1) fails to affect adipogenesis in immortalized mouse embryonic fibroblasts (iMEF) (LB149)
Authors: Holdaway Brett , Naik Chaitasi , Chang Yingzi
Published: June 2021

Background: Increased adipogenesis is associated with chronic inflammation. MCPIP1 has been shown to suppress inflammation through regulating pro‐inflammatory cytokines in the immune system. Recent studies found that MCPIP1 is involved in the process of adipogenesis in 3T3‐L1 cells but the results are controversial. Our preliminary data indicates that MCPIP1 knockout impaired hepatic insulin signaling. The current study was designed to deterimine if MCPIP1 affects adipogenesis by regulating the insulin signal transduction pathway. Methods: MEFs were isolated from both MCPIP1 heterozygous (no phenotypic changes) and knockout C57/BL6 mice and immortalized. At 2 days post‐confluency, the cells were treated with or without a differentiation cocktail containing dexamethasone, IBMX, trogliterazone, and different concentrations of insulin. After 48 hours, cells were switched to medium containing 10% FBS with or without the different concentrations of insulin for the remainder of the differentiation period. Adipocyte differentiation was measured using Oil Red‐O staining by visualizing the intracellular lipid droplets. Lipids were extracted with isopropanol. The concentration of lipid was measured, calculated, and expressed by normalizing to the protein concentration. Results: Although a slight increase in adipogenesis was seen in the MCPIP1 KO model compared to the heterozygous model, overall there was no significant difference between these groups (p>0.05). Also, no difference in adipogenesis was observed among the different concentrations of insulin groups in cells from either heterozygous or MCPIP1 KO mice (p>0.05). Conclusion: From the data we collected thus far, we conclude that MCPIP1 might not play a key role in adipogenesis in iMEFs. Insulin may not be required to stimulate adipogenesis in iMEFs isolated from MCPIP1 knockout and heterozygous mice.

Grant Funding Source: Supported by ATSU‐KCOM Biomedical Sciences Program
Effect of Aloe Vera gel and Selenium on Cisplatin‐induced oxidative stress in Wister albino rats (LB155)
Authors: Imaga Ngozi , OSIME E , Ezeji S , Okafor Uzoma
Published: June 2021

Cisplatin (Cis‐diamminedichloroplatinum II, CP) is an important chemotherapeutic agent, useful in the management of cancers, but with side effects like nephrotoxicity. The present study studied the effect of Aloe vera gel (AVG) and selenium on Cisplatin induced oxidative stress on the kidneys and livers of male and female Wister albino rats, injected with cisplatin (7mg/kg), selenium (6mg/kg) and Aloe vera (6mg/kg), alone or in combination. The results show that though CP increased lipid peroxidation (LPO) and decreased reduced glutathione (GSH) concentrations in male Wister albino rats compared to female Wister albino rats, treatment with Aloe vera; reversed CP‐induced kidney and liver damage in both male and female rats. While pre‐treatment with Selenium and Aloe vera limited CP‐induced alterations of antioxidant enzyme activities and significantly prevented CP‐induced kidney and liver damage. The levels of Liver and Renal functioning enzymes, Hematological parameters and Cholesterol, TG and LDL levels in the untreated group increased while the treated and pretreated groups had a lower level of these enzymes with the Aloe vera group having the lowest levels of these enzymes. Histological studies on the kidneys and livers of male and female Wister albino rats showed significant damage.

In conclusion, research showed that Aloe vera and Selenium ameliorated oxidative stress and loss of cellular antioxidants, thus acting as an anti‐lipidemic agent and also an immune booster.
The role of MCPIP‐1 in maintaining lipid homeostasis (LB156)
Authors: Moody Joshua , Sedinkin Jessica , Chang Yingzi
Published: June 2021

Background:Increased inflammation is associated with alterations of lipid and lipoprotein metabolism. Recent studies suggest that MCPIP1 (Monocyte Chemotactic Protein induced Protein‐1) may have a role in maintaining normal metabolic balance by negatively regulating chronic inflammation. Our preliminary data revealed that the MCPIP1 deficient (MCPIP1‐/‐) mice have reduced body lipid deposits compared to control mice. The current project was designed to test if MCPIP1 is involved in maintaining lipid homeostasis by affecting hepatic lipid production and distribution. Methods: MCPIP1‐/‐ mice (C57/BL6 background, 6 weeks old) were identified by PCR. The serum and liver from control and MCPIP1‐/‐ mice were collected after fasting. Serum lipids (LDL/VLDL‐cholesterol and total triglyceride) and liver lipids (total cholesterol and triglyceride) were measured using commercially available kits. Results: The data collected from sixteen samples (eight control and eight MCPIP1‐/‐) showed that in MCPIP1 ‐/‐ mice the mean serum HDL‐cholesterol and total triglyceride concentrations were about 49% and 31% lower respectively, compared to control mice. In contrast, serum concentration of LDL/VLDL‐cholesterol in MCPIP1‐/‐ mice increased about 66% when compared to control. Triglyceride in the liver tissue of MCPIP‐/‐ mice was also drastically decreased (72% lower than control). No changes were observed in total cholesterol in liver tissue. Conclusion: The lack of MCPIP1 is associated with alterations of lipid homeostasis.

Grant Funding Source: Supported by KCOM Graduate Program in Biomedical Sciences
Development of subclass‐specific antivirulence inhibitors against disulfide oxidoreductase DsbA (LB193)
Authors: Premkumar Lakshmanane , McMahon Roisin , Kurth Fabian , Duprez Wilko , Martin Jennifer
Published: June 2021

The emergence of “superbugs” bacterial strains coupled with a steady decline in the new antibiotics is a growing public health and economic concern. Novel antibacterial strategies, new molecular targets and new classes of drugs with long‐term clinical effectiveness are urgently needed. Disulfide bond forming proteins (DsbA and DsbB) are a master regulator of bacterial virulence and pathogenesis. DsbA/DsbB disruption affects multiple downstream effector molecules, resulting in pleiotropic effects on the virulence of important human bacterial pathogens without exerting growth inhibition. These findings identify DsbA/DsbB as a target for a new class of bacterial antivirulence that disarm pathogenic bacteria rather than killing them. We explored the druggability of twelve well‐characterized DsbA enzymes for the overall fold, the surface properties, the conformations of three loops contributing to the binding surface and the sequence identity of residues contributing to these loops. Two distinct structural classes were identified, classes I and II, which are differentiated by their central β‐sheet arrangements and roughly separate the Gram‐negative from Gram‐positive DsbAs. The classes can be further subdivided into a total of four subclasses on the basis of surface features, which are supported by bioinformatic analyses and a wealth of biochemical/biophysical characterizations. In the context of inhibitor development, our findings point to the opportunity to develop a single antivirulence drug effective against DsbAs encoded by at least seven enterobacterial pathogens. I will present our current work on the development of structure‐based peptidomimetic inhibitors targeting this pivotal mediator of bacterial virulence.

Grant Funding Source: australian research council