bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of diagnostic and therapeutic targets of pancreatic cancer using proteomic approaches
Authors: Pandey Akhilesh , Jimeno Antonio , Molina Henrik , Hruban Ralph H , Maitra Anirban , Hidalgo Manuel , Harsha HC 
Published: June 2021

Pancreatic cancer remains one of the most lethal of all the solid malignancies. Using a quantitative proteomic strategy, we have carried out profiling studies to identify novel biomarkers and therapeutic targets in pancreatic cancer. Phosphotyrosine profiling revealed aberrant activation of epidermal growth factor receptor (EGFR) in a subset of pancreatic cancers. This correlated with phospho‐EGFR staining and response to the EGFR inhibitor, erlotinib, in mice carrying pancreatic cancer xenografts demonstrating the utility of activated EGFR as a biomarker that could be used to guide therapeutic decisions. Proteomic profiling of membrane fractions identified several proteins that are differentially expressed in pancreatic cancers. Immunohistochemical validation of one of the candidate markers, myeloid associated differentiation marker (MYADM), confirmed overexpression of this molecule in greater than 80% of pancreatic adenocarcinomas. Our studies emphasize the utility of advanced proteomic approaches in identifying novel biomarkers and therapeutic targets.This work was supported by Sol Goldman Trust for Pancreatic Cancer Research.
CNS changes after chronic sleep deprivation: roles in both food intake and metabolism
Authors: Hoffman Gloria 
Published: June 2021

In humans and animal models, chronic sleep loss stimulates feeding and leads to metabolic interactions associated with signs of the metabolic syndrome and progression to diabetes II. Understanding how sleep deprivation might produce these effects is more complicated and involves dissection of central nervous system pathways that normally regulate food intake and those which control peripheral metabolism. For the former, hypothalamic neuropeptide Y (NPY) and proopiomelanocortin (POMC) are key systems governing feeding. Sleep deprivation up‐regulates NPY and down‐regulates POMC in the hypothalamus that accounts for the hyperphagia. For the changes in metabolism, usually hyperphagia is accompanied by a slowing of metabolic rate but the opposite is seen in chronic sleep deprivation. The CNS's role in regulating metabolic rate is less well understood, although histamine may be involved. Central histamine neurons not only affect the maintenance of wakefulness, but are also regulators of peripheral metabolism via actions at the preganglionic sympathetic neurons. The rate‐limiting enzyme for histamine synthesis, histidine decarboxylase, is up‐regulated during sleep deprivation, and these changes predict the attenuation of body weight (prompted by hypermetabolism). The relationship of changes in histamine synthesis to those of glucose suggests that the amine might also be responsible for changes which lead to metabolic syndrome. Elevations in glucose:insulin ratios in sleep deprived rats were positively correlated with the extent of increased histidine decarboxylase gene expression. Together, these data raise the possibility that a dysregulation of histamine function when sleep is impaired might serve to trigger increased sympathetic tone and metabolic changes leading to diabetes.Supported by a Pilot and Feasibility grant from the Clinical Nutrition Research Unit of Maryland, P30DK072488.
Deep sequencing of mRNA to understand function of splicing regulatory factors
Authors: Burge Chris 
Published: June 2021

Splicing regulatory elements (SREs) and the associated splicing factors play central roles in the control of pre‐mRNA splicing and in exon evolution. We are studying in depth the regulatory properties of representative splicing factors, including the widely expressed factor hnRNP H, and the muscle‐ and brain‐specific factors of the CELF and Muscleblind families, using knockout or knockdown followed by deep sequencing of mRNAs (KO‐Seq or KD‐Seq), cross‐linking/immunoprecipitation/sequencing (CLIP‐Seq), and other approaches. In this talk I will discuss our progress towards understanding the functions of these factors, including the finding that the activity of G‐run intronic splicing enhancers (ISEs) and hnRNP H is highly dependent on the strength of the adjacent 5' splice site sequence, and the functional and evolutionary implications of this finding.Our work is supported by the NHGRI and the NIGMS.
Blue light photosensors: Examples of environmentally‐regulated protein/protein interactions
Authors: Gardner Kevin H. , Nash Abigail I. , Ko Wen‐huang , Correa Fernando , Wu Qiong 
Published: June 2021

Many biological processes are regulated by controlling protein conformation in response to specific environmental cues. This is often mediated by modular protein domains that use environmentally‐triggered changes in bound cofactor conformation or configuration to regulate protein/protein interactions. Photoreceptors exemplify these principles, as they depend on photochemistry mediated by organic chromophores to detect light. In particular, several classes of blue light sensors use flavin chromophores that alter their interactions with the surrounding protein to initiate conformational changes and signaling. We have used solution NMR spectroscopy and other biophysical methods to examine these processes in two classes of photosensory domains.The first of these are Light‐Oxygen‐Voltage (LOV) domains, members of the PAS family of environmental sensors. Illumination generates a covalent protein‐flavin bond within the α/β core of LOV domains, leading to conformational changes in the β‐sheet adjacent to the chromophore. These changes are propagated to non‐canonical protein elements on the other side of this sheet, modifying their function. We will show the generality of this process with data for several classes of LOV‐containing proteins, including serine/threonine kinases, histidine kinases and DNA binding proteins.We will compare these results with parallel studies of BLUF domains (sensors of Blue Light Utilizing FAD), which use different protein topology and photochemistry than LOV domains, but appear to harness light‐induced conformational changes in a similar manner despite these fundamental differences.This work is supported by grants from the NIH (R01 GM081875) and the Robert A. Welch Foundation (I‐1424).
The Role of Hepatocyte Growth Factor in Satellite Cell Mediated Angiogenesis
Authors: Flann Kyle L. , Rathbone Chris R. , Allen Ron E. , Rhoads Robert P. 
Published: June 2021

Skeletal muscle regeneration is a multifaceted process involving the spatial and temporal coordination of myogenic and angiogenic events. Satellite cells are well‐established myogenic precursor cells responsible for skeletal muscle growth and repair. We have recently demonstrated that satellite cells also promote angiogenesis, in part, through the secretion of soluble‐acting factors. Satellite cells produce a number of growth factors, some with pro‐angiogenic properties, although it not clear which of these growth factors participate in satellite cell‐mediated angiogenesis. One likely candidate protein is hepatocyte growth factor (HGF). To identify a role for HGF in satellite cell mediated angiogenesis, we employed an in vitro model consisting of rat microvascular fragments (MVF) embedded in a three‐dimensional collagen matrix. In an effort to block HGF action, various levels of anti‐HGF antibody were added to rat satellite cell conditioned medium and fed to MVF cultures. Following 5 days of culture, MVF were analyzed for indices of angiogenesis. Sprout number and length were decreased in a dose‐dependent manner by increasing levels of HGF inhibition. Addition of recombinant HGF during HGF inhibition sufficiently rescued angiogenesis in the MVF cultures. This data indicates that satellite cell‐derived HGF plays an important role in satellite cell mediated angiogenic processes.Grant Funding SourceNIH
Serum‐dependent epithelial cell sheet shrinkage upon detachment from temperature‐responsive culture surfaces
Authors: Kondo Makoto , Murakami Daisuke , Yamato Masayuki , Takagi Ryo , Namiki Hideo , Okano Teruo 
Published: June 2021

Primary oral mucosal epithelial cells show cell stratification similarly to those in vivo under the optimum culture conditions supplemented with serum. By temperature reduction, all the cells on temperature‐responsive surfaces are spontaneously detached as a single contiguous cell sheet since the surfaces change hydrophilic. We have utilized these cell sheets in regenerative medicine of cornea and esophagus. Interestingly, harvested cell sheets shrank to 50% of the original size. By utilizing porous membrane, stratified epithelium‐like cell sheets were also harvested even without serum. However, the harvested cell sheets didn't show any shrinkage, while cell proliferation and colony‐forming efficiency were the same with or without serum. In addition, cell adhesion on culture substrata was significantly weak under the serum‐free culture condition. Electron microscopy revealed that the basal surfaces of cell sheets cultured in the serum‐free condition had less minute processes participating in cell adhesion onto substrata. DNA array analyses showed some inflammatory‐related genes including MMP‐9, IL‐1α, IL‐1α receptor, and calpain 5 were significantly upregulated by serum. These findings would prompt the further investigations to understand underlying molecular mechanisms to achieve reproducible, safe, and effective clinical applications of epithelial cell sheets.Grant Funding SourceGrant‐in‐Aid for Scientific Research
Endoplasmic reticulum stress response is induced by sulfur mustard in the mouse ear vesicant model
Authors: Chang Yoke‐Chen , Soriano Melannie , Nguyen Michael , Casillas Robert P , Sabourin Carol L. , Gordon Marion K. , Gerecke Donald R. 
Published: June 2021

Time‐related changes in the histopathology of mouse skin occur after topical exposure to the vesicant agent, bis(2‐chloroethyl) sulfide (SM) using the mouse ear vesicant model (MEVM). Some of these changes include increasing edema, detachment of the epidermis from the dermis, and upregulation of laminin‐332. Endoplasmic reticulum stress response (ESR) was observed by confocal microscopy. Microarray analysis and RT‐PCR experiments indicated there was upregulation of several heat shock proteins and folding chaperones such glucose‐regulated protein 78 and GRP94 in the ER. It confirmed the confocal observations and suggested that ER stress occurs very quickly in the MEVM. The accumulation of laminin γ2 protein, one of the chains of laminin‐332, in the ER was visualized by confocal microscopy and co localized with the ER chaperones. This accumulation appeared specifically in the migrating, but not proliferating cells. These observations are consistent with recent reports that laminin‐332 is found in migrating, transformed epithelial cells that have left the cell cycle, but not in proliferating cells. These results suggest that laminin γ2 is misfolded after SM treatment, resulting in decreased secretion and reduced overall amounts of laminin‐332 in the extracellular matrix. This would explain the observation that there is a delayed wound healing response evident in this wound model.Grant Funding SourceES005022, ES004738, EY09056, and the NIH CounterACT Program through NIAMS U54AR055073
HEALING OF CORNEAL WOUNDS INDUCED BY VESICANTS
Authors: DeSantis Andrea , Hahn Rita A , Beloni John , Schultz Gregory , Heindel Ned , Svoboda Kathy KH , Babin Michael C , Gerecke Donald R. , Gordon Marion K 
Published: June 2021

Vesicants cause injury to the corneal epithelial‐stromal junction. Matrix metalloproteinase (MMP) activity delays proper wound healing. We followed healing of organ cultured rabbit corneas exposed to half mustard (CEES) and nitrogen mustard (NM) with subsequent addition of MMP inhibitors or a steroid. Corneas were cultured adapting the method of Foreman et al, Exp. Eye Res. 62:555, 1996. Vesicants were applied, and after 2 hr, were rinsed off. Over the next 22 hr medium alone or medium containing doxycycline, sancycline, Ilomastat, or Tobradex was added. Samples were analyzed by light and electron microscopy (EM). Half mustard (CEES) caused mild injury affecting basal cells. These rarely separated from the stromal layer. EM showed focal degradation of the basement membrane and dissolution of hemidesmosomes. Nitrogen mustard injury was more severe. Regions between the anchoring complexes showed epithelial‐stromal separation. EM showed adhesion complex remnamts prevented total separation. For CEES injury doxycycline, sancycline and Ilomostat ameliorated effects. For nitrogen mustard injuries, all 4 agents improved the histological appearance of the epithelial‐stromal border as compared to vesicant treated samples. However these agents did not totally eliminate separations between the layers.Grant Funding SourceNIH EY009056 and U54AR055073
PROSTATIC HOX GENES: EXPRESSION DURING DEVELOPMENT AND IN TRAMP TUMOR CELLS
Authors: Wang Billy C , Keith Ashena L , Pira Charmaine U , Feenstra Jennifer M , Oberg Kerby C 
Published: June 2021

Hox transcription factors play critical roles during development and reactivation may participate in tumorigenesis. For example, some prostate cancers overexpress androgen sensitive HOXC8, while others upregulate androgen insensitive HOXB13. A comprehensive Hox expression profile during prostate development has not been described. We generated a prostatic Hox expression profile in an effort to identify candidate Hox genes critical to prostate development and potentially tumorigenesis.Mouse prostates at various stages of development [0, 2, 6, 13, and 24 weeks of age] were collected RNA isolated, cDNA generated and semi‐quantitative PCR performed. We also examined Hox expression in the Transgenic Adenocarcinoma of Mouse Prostate (TRAMP) cell line. Hox genes with profiles of interest were subjected to quantitative PCR for confirmation.Hoxa10 is expressed through out prostate development and in TRAMP cells implicating it as a marker of prostate tissue similar to its corresponding expression in the female endometrium. Hoxb3 and d8 are present during development, and in TRAMP cells, but not prostates of older males. Furthermore, Hoxd11 and b13 have robust expression in older males, but are absent in TRAMP cells. Our analysis has identified prostate marker genes, genes that appear to be developmentally regulated and genes that appear to be reactivated or specifically repressed in the TRAMP tumor cells.Grant Funding SourceNIH, LLU Pathology Group
Dyad Pedagogy: A New Education Paradigm for Allied Health Programs
Authors: Chaudhri Ali Aftab , Sherman Lloyd , Marquez Samuel 
Published: June 2021

Allied health programs attract students from diverse educational backgrounds, though most have only been exposed to traditional lecture‐based modalities. While quantitative performances can be excellent in these programs, difficulties arise assessing if students can function in groups, a critical issue in the current interdepartmental health care model. The problem may be a consequence of the prevalence of lecture over non‐lecture class models, to which some have suggested re‐structuring course material into group projects. But would working in groups adversely affect learning required content? To explore this question, 21 sonography students in a gross anatomy class were randomly assigned into 9 dyads & 1 triad, and given weekly problem‐based assignments involving key anatomical concepts and oral projects. Dyads were assessed by pre‐ and post‐test comparisons, and qualitative performances on weekly assignments tracked over time. Early data showed improved post‐test results, increasingly sophisticated qualitative content in weekly assignments, and increased confidence in self‐expression. This suggests dyad pedagogy can be readily incorporated into anatomical instruction without any negative impact on learning critical content, and has the added value of encouraging students to learn from each other as well as helping them develop other workplace‐relevant skills.Grant Funding SourceDO NOT HAVE FUNDING
Student laboratory presentations as a learning tool in anatomy education
Authors: Chollet Madeleine Blair , Garofalo Evan , Teaford Mark , DeLeon Valerie 
Published: June 2021

Previous studies have shown that students who complete oral presentations in the anatomy laboratory believe they understand the material better and retain it longer; however, we have found no studies that empirically test such outcomes based on exam scores. The purpose of this study was to assess the effectiveness of oral lab presentations on exam performance. Specifically, we tested whether students (n = 132) performed better on exam questions on topics covered by their oral presentations than on other topics. Each student completed two graded[vbd1], 12‐minute lab presentations on two different assigned topics (e.g., thorax) during the course. Each student also took three examinations, each covering a third of the course material. Exam questions were characterized by type (memorization, pathway, analytical, other). A paired t‐test revealed that students performed better on topics covered by their presentations than on topics not covered by their presentations (p < 0.05). Two‐way repeated measures ANOVA (presentation‐by‐question type) also indicated a significant effect of question type on presentation‐related improvement in exam scores. For "pathway" questions, presenting students scored on average 5.6% higher on topics covered by their presentations than on topics not covered by their presentations (p < 0.05). These results demonstrate empirically that oral presentations are an effective learning tool.Grant Funding SourceNone
Understanding Anatomy Through the Art of Sculpting
Authors: Svigals Philip Zachary , Márquez Samuel 
Published: June 2021

Understanding anatomical structures in the context of their topographical position provides a basis for mastery of our discipline. However, the art of sculpture offers the opportunity for the health professional to improve his/her perception while greatly enhancing their understanding of anatomy. As a professional sculptor and medical student, one of the authors (PZS) was asked by Director of anatomy at SUNY Downstate Medical School (SM) to create a life size model of a heart with coronary vessels. An interactive version of the sculpture was posted online allowing students to rotate the model 360 degrees while multiple copies of the piece were distributed throughout the labs. Using images from Grant's and Netter Atlases PZS transformed the 2D into 3D structures by evaluating the contours, volume and proportion; improving the right brain's visual‐spatial perception and the left brain's praxis. Through molding the clay into anatomically correct structures by viewing the piece from every angle, spatial relationships were registered, understood and committed to memory. Practice analyzing the form trains the eye to see in greater detail and to better synthesize a sense of the whole. These skills allow a physician to readily differentiate the abnormal from the normal and make accurate decisions in a surgical or clinical setting. Common goals of surgeons and artists lie in the careful evaluation of their patients/subjects in all dimensions and visualizing the finished product in order to properly plan and execute a surgical procedure or sculpture. As the plastic surgeon places the scalpel to tissue to reconstruct an absent ear or deformed nose, so too must the sculptor meet similar concerns about size, shape, position and proportion as they place the chisel to stone. A sculpture workshop to help teach anatomy and develop valuable tactile and observational skills for the physician is being planned for the fourth year curriculum.Grant Funding Sourcen/a
NPC2 facilitates bidirectional transfer of cholesterol between NPC1 and lipid bilayers, a potential step in cholesterol egress from lysosomes.*
Authors: Infante Rodney , Brown Michael , Goldstein Joseph 
Published: June 2021

The trafficking of lipoprotein‐derived cholesterol from lysosomes is dependent on the polytopic membrane‐bound Niemann‐Pick C1 (NPC1) and the soluble Niemann‐Pick C2 lysosomal proteins. The requirement for these proteins in the transport of cholesterol out of the lysosomes remains unclear. Previously, we demonstrated the ability of the N‐terminal luminal domain of NPC1, hereinafter called NPC1(NTD), to bind cholesterol with nM affinity. We and others also showed the ability of NPC2 to bind cholesterol with similar affinity. Recently, we established an in vitro assay detecting the movement of [3H]cholesterol between these two proteins and model membranes. NPC2 readily transfers or receives [3H]cholesterol to and from phosphatidylcholine liposomes, relative to NPC1(NTD). The bidirectional transport of [3H]cholesterol between NPC1(NTD) and liposomes is accelerated over a 100 fold in the presence of NPC2. The naturally occurring mutant (Pro120Ser) form of NPC2 did not demonstrate significant cholesterol binding and had a reduction in the facilitation of cholesterol transport between NPC1(NTD) and liposomes. These studies begin to define the dual requirement of both proteins in the egress of lipoprotein‐derived cholesterol out of the lysosomes, thus explaining why mutations in either protein cause a similar clinical phenotype.*Infante, RE, et al. (2008) NPC2 facilitates bidirectional transfer of cholesterol between NPC1 and lipid bilayers, a step in cholesterol egress from lysosomes. Proc Natl Acad Sci USA 105:15287‐15292.
Role of LFA‐1 in the transmission and pathogenesis of human immunodeficiency virus type 1 (HIV‐1)
Authors: Walker Tiffany Nicole , Hildreth James EK 
Published: June 2021

HIV‐1infection induces formation of a virological synapse wherein CD4, chemokine receptors, and cell adhesion moleculessuch as the integrin LFA‐1 [RNSB1]form localized domains on the cell surface. Previous studies have shown that LFA‐1 on the surface of HIV‐1 particlesnot only retains its cellular function but also enhances virus attachment to susceptible cells by binding its counterreceptor ICAM‐1. Findings from our laboratory revealed that monoclonal antibodies (Mab) specific for LFA‐1 blocked HIV‐1 mediated syncytia formationand enhanced neutralization by antibodies from AIDS patients and by gp120 Mabs. The objective of this study is to determine if LFA‐1/ICAM‐1 interaction plays a limiting role in apoptosis, a process linked to both HIV‐1 infection and integrin biology such that disruption of this interaction leads to increasedapoptosis in HIV‐1‐infected cells. Using the TUNEL assay, we observed increased cell death in HIV‐1‐infected primary T cells treated with anti‐LFA‐1 Mab[RNSB2], as well as increased caspase 8 activation. HIV‐1‐infected cells treated with anti‐LFA‐1 Mab also released less virus compared to HIV‐1‐infected cells alone. These results suggests that anti‐LFA‐1 Mab blocks HIV‐1 infection by inducing apoptosis and that LFA‐1‐mediated signaling may be necessary to prevent HIV‐1‐induced apoptosis, thereby contributing to the spread of infection.Supported by NIH (R01HD040772)