bluuebunny/crossref_metadata_2025_split huggingface dataset:
Caffeine free polyphenolic extracts from Yaupon holly (Ilex vomitoria) have chemopreventive potential and reduce the expression of inflammatory genes in non‐cancer human myofibroblast (CCD‐18) cells
Authors: Noratto Giuliana Doris , Kim Youngmok , Talcott Steve Terel , Mertens‐Talcott Susanne U. 
Published: June 2021

The objective of this study was to evaluate chemopreventive potential of different fractions of phenolics isolated from green tea (GT) and yaupon (YU) on human HT‐29 colon cancer cells and the anti‐inflammatory effects on colonic myofibroblasts CCD‐18 cells. Infusions from GT and YU leaves were fractionated into phenolics acids (Pa) and flavonoids (Fv) followed by caffeine removal (noC). Proliferation was determined by MTT assay, inhibition of hydrogenperoxide‐induced reactive oxygen species (ROS) by dichlorofluorescein (DCF) assay, and modulation of gene expression by RT‐PCR. Among extracts the order of antiproliferativepotency in HT‐29 cells was YU‐Fv‐noC > YU‐Fv > GT‐noC ~ GT. The IC50 values of YU‐Fv‐noC for HT‐29 and CCD‐18 were 15 and 68 mg gallic acid equiv./L, respectively.YU‐Fv‐noC showed low toxicity exerted in non‐cancer colon cells, though the protective effect against the H2O2 induced ROS was not significant. However, YU‐Fv‐noC significantly decreased the expression of the pro‐inflammatory genes IL‐6 and COX‐2, up to 99% and NF‐κB from 8 to 35% compared to untreated cells. The expression of cell‐protective catalase was increased by 1.1 to 1.4 fold in a dose‐dependent manner at 10‐40mg/L. In summary, our results indicate that flavonoids from YU seem to have anti‐cancer effects and also may have potential for use in chemoprevention based on their anti‐inflammatory effects.
Estrogenic compounds alter cell growth in non‐cancerous colonocytes
Authors: Weige Charles Conan , Allred Clinton D 
Published: June 2021

Studies have shown that hormone replacement therapy can reduce the risk of colon cancer in post‐menopausal women, and dietary phytoestrogens are also associated with lower risk of the disease. We have demonstrated that estradiol (E2) and genistein (Gen), a model soy phytoestrogen, do not inhibit colon cancer cell growth regardless of whether the cell expresses estrogen receptor beta (ERβ). These data demonstrate the need to determine the role of estrogenic compounds in non‐cancerous colonocytes, but data has been limited due to lack of appropriate in vitro models. We have employed young adult mouse colonocyte (YAMC) cells which were shown to express ERβ. Treatment of YAMCs with E2 or Gen caused a reduction in cell number in a dose responsive manner. This effect was significantly inhibited by treatment with ICI, an ER antagonist. Apoptosis was induced in response to estrogenic treatments, but preliminary data suggests these treatments do not significantly alter the cell cycle. When the oncogene Ras is over‐expressed in YAMC cells, the effects of the compounds are lost. This data is critical because it is the first to show estrogenic compounds alter the cellular activity of non‐cancerous colonocytes, which is the first step towards determining how these compounds reduce colon cancer risk.Grant Funding SourceThe American Institute for Cancer Research
Selenium‐regulated expression of non‐selenoprotein genes
Authors: Raines Anna M. , Sunde Roger A. 
Published: June 2021

Recent studies have linked super‐nutritional Se intake to both beneficial and adverse outcomes such as lowered risk for cancer and increased risk for type II diabetes. These paradoxical effects of high Se intake highlight the need for biomarkers of high Se status. While a subset of selenoprotein mRNAs are useful as biomarkers of Se deficiency, no selenoprotein mRNAs further increase at super‐nutritional intakes, precluding their use as biomarkers of high Se. To identify non‐selenoprotein genes regulated by Se, we used microarrays to analyze gene expression in liver and kidney from mice fed < 0.007 (‐Se), 0.05 (~Se), or 0.2 μg Se/g diet (+Se). Comparison analysis of expression in +Se vs. ~Se and +Se vs. ‐Se yielded 103 unique candidate biomarker genes changed = 1.4 fold. Detected selenoproteins show the expected pattern of Se‐regulation. The Se‐dependent expression of non‐selenoprotein genes is being confirmed by qRT‐PCR and tested in rats fed 0‐0.8 μg Se/g diet. So far, we have identified 6 genes changed > 3 fold only in +Se, and 1 transporter gene upregulated only in ‐Se in both mice and rats. Interestingly, four distinct patterns of Se‐regulation have emerged among the candidates: high in +Se; low in +Se; high in ‐Se; low in ‐Se (selenoprotein pattern). Candidate genes may be useful as high Se biomarkers and could be involved in Se homeostasis in Se deficiency or Se excess. Support: DK74184, DK07665, WISC04909Grant Funding SourceNIH
Effects of signaling through the retinoic acid receptors in motor neurons: implications for amyotrophic lateral sclerosis
Authors: Kolarcik Christi , Bowser Robert 
Published: June 2021

Amyotrophic lateral sclerosis (ALS), the most common form of motor neuron disease, is a progressive, fatal neurodegenerative disorder which is poorly understood and for which effective therapeutic interventions are lacking. Our laboratory has identified potential biomarkers for ALS and has characterized these proteins and related signaling pathways using a primary motor neuron‐enriched cell culture system. We focused on retinoid signaling as we have observed alterations in this pathway in sporadic ALS patients. Using all‐trans retinoic acid (ATRA) to stimulate the retinoic acid receptors (RARs), we further investigated the impact of signaling through the RARs on motor neuron survival. In the presence of ATRA, the number of branch points/cell was decreased in motor neurons. RAR β was localized to the nucleus irrespective of the presence of ATRA. RARα localized to axonal processes without ATRA, and this decreased with increasing ATRA concentrations. As similar phenomena have been observed in sporadic ALS patients, we believe that motor neurons may attempt to recapitulate a developmental process in an effort to maintain axonal connections as ALS progresses.Research Support: NIH grant ES013469 (RB); NIH T32 EB001026 (CK); NIH T32 05 TL1 RR024155‐02 (CK)
Dickkopf‐1 regulates epithelial cell migration by inhibiting directional orientation
Authors: Koch Stefan , Capaldo Christopher T , Nava Porfirio , Skerra Arne , Sacks David B , Parkos Charles A , Nusrat Asma 
Published: June 2021

Wnt signaling pathways regulate proliferation, motility and survival in a variety of human cell types. Dickkopf‐1 (Dkk‐1) is a secreted Wnt antagonist that has been shown to regulate tissue homeostasis in the intestine. In this report, we show that Dkk‐1 is secreted by migrating intestinal epithelial cells after wounding and during intestinal inflammation in vivo, and inhibits cell migration by attenuating directional orientation. We found that physiological concentrations of recombinant Dkk‐1 protein are sufficient to inhibit polarization of the microtubule organizing center and Golgi apparatus towards the leading edge of migrating epithelial cells. Cells exposed to Dkk‐1 exhibit a strong, mis‐localized activation of Cdc42, which coincides with an irregular localization of the polarity protein Par6 and increased phosphorylation of atypical PKC. In contrast, classical PKC phosphorylation is attenuated in the presence of Dkk‐1, suggesting that the observed effects on polarized cell migration might be mediated by inhibition of non‐canonical Wnt pathways. Taken together, these data demonstrate a previously undescribed role of Dkk‐1 in the establishment of directional polarity in epithelial cells, which contributes to the detrimental effects of Dkk‐1 in vivo.Supported by grants from the National Institutes of Health (DK72564, DK61379 and DK79392 to C.A.P., DK53202, DK55679, DK59888 to A.N.).
Talin mediates monocyte α4β1 integrin‐mediated migration, but not chemokine‐triggered α4β1 affinity up‐regulation or adhesion
Authors: Hyduk Sharon , Rullo Jacob , Puig Cano Adrianet , Chen Mian , Cybulsky Myron I. 
Published: June 2021

α4β1 integrin plays an important role in monocyte adhesion and emigration. Activation by chemokines and chemoattractants is required to increase α4β1 integrin affinity and mediate adhesion to VCAM‐1 expressed by cytokine‐activated endothelium. We investigated the role of talin, a cytoskeletal protein that interacts with integrin cytoplasmic tails, in α4β1 integrin‐dependent functions using formyl peptide receptor‐transfected U937 monocytic cells. fMLP‐induced affinity up‐regulation, measured by binding of soluble LDV‐FITC peptide, was unaffected by siRNA knockdown of talin‐1 or sequestration of talin through expression of a dominant inhibitory talin‐binding fragment of phosphatidylinositol phosphate kinase type I‐90. Similarly, talin‐1 knockdown did not inhibit fMLP or SDF‐1‐stimulated adhesion to VCAM‐1. Talin was however, essential for PMA‐induced adhesion to VCAM‐1, but not PMA‐induced α4β1 integrin affinity up‐regulation. In addition, talin knockdown reduced fMLP‐driven, α4β1 integrin‐dependent chemotactic migration across VCAM‐1 coated filters.These results suggest that talin association with the cytoplasmic tail of α4β1 integrin is not involved in chemokine‐induced affinity changes or adhesion. However, talin plays an important role in α4β1 integrin‐mediated chemotactic migration and PMA‐induced adhesion to VCAM‐1, steps that follow affinity modulation. Funded by CIHR.
Gender modulation of cardiac gene expression in rats with chronic volume overload
Authors: Walton Karen L. , McLarty Jennifer L. , Bennett Shante' , Melendez Giselle C. , Sabo‐Attwood Tara , Brower Gregory L. 
Published: June 2021

We have previously described gender differences in cardiac remodeling secondary to chronic volume overload in rats. However, the mechanisms underlying ovarian hormone mediated cardioprotection have not yet been elucidated. Accordingly, this study sought to identify altered cardiac gene expression contributing to the protection from adverse cardiac remodeling seen in female rats. To that end, left ventricular (LV) gene expression in male and intact and ovariectomized adult female rats (N=3 per group) with an aortocaval fistula was compared to sham‐operated controls. At three days post‐surgery, the hearts were excised, separated and the LV prepared for RNA isolation. An Applied Biosystems Low Density Inflammation Array allowed us to simultaneously examine 96 genes of interest. There were significant gender differences observed in the expression of genes kallikrein‐15, cyclooxgenase‐1 and ‐2, thromboxane synthases and nerve growth factor which were subsequently confirmed by RT‐PCR. Cytokine gene expression, including the TNF‐alpha superfamily, IL‐6 and stem cell factor were also similarly affected. Thus, ovarian hormone regulation of prostaglandin, cytokine and serine protease inflammatory gene expression in the heart are implicated in the attenuation of pathogenic remodeling induced by a chronic volume overload.Funding Sources: NIH grants RO1‐HL‐62228 and RO1‐HL‐073990
Role of the RGS (regulator of G protein signaling) domain of Axin in vertebrate axis formation
Authors: Schneider Patricia , Slusarski Diane , Houston Douglas 
Published: June 2021

The Wnt signaling network has major roles in developmental processes, human diseases and stem cell biology. A protein complex that includes Axin, APC and GSK3 tightly regulates this signaling. Axin, a key player in this complex, contains four critical domains: a β‐catenin binding domain, a GSK binding domain, an RGS domain and a DIX domain. Our study focuses on the role of the Axin‐RGS domain. Typically, RGS domains contain a conserved asparagine (Asn), critical for the ability to bind heterotrimeric G‐proteins. Interestingly, we find that the Axin‐RGS domain encodes a glutamine (Gln) at the equivalent position, suggesting a novel function for Axin‐RGS. We tested whether the Axin‐RGS domain functions in the context of Wnt signaling. We generated point mutations that converts the original Gln to Asn, predicted to increase affinity for Gα, and that converts Gln to Ala, predicted to abolish binding activity. We tested for the ability of the mutant forms to rescue Axin function in masterblind (mbl) zebrafish mutant embryos and in antisense morpholino knockdown of Axin in zebrafish and frog (Xenopus laevis). We found that the mutant constructs showed a differential ability to restore normal development in fish and frog embryos. These results suggest that the Axin‐RGS domain may be playing a role in regulating zygotic Wnt signaling.Grant Funding SourceRoy J. Carver Charitable Trust
Sleep deprivation and stress: an inseparable pair
Authors: Suchecki Deborah 
Published: June 2021

Prolonged sleep deprivation (SD) represents a stressful event for it activates the neuroendocrine stress response, as reflected by increased plasma levels of adrenaline, adrenocorticotropic hormone (ACTH) and corticosterone. However, the extent to which SD activates the hypothalamic‐pituitary‐adrenal (HPA) axis can be modulated by environmental factors. Using two versions of the platform method ‐ individual or group SD for 96h, we observed that group support reduces anxiety‐like behavior of animals in the elevated plus maze and, consequently, the stimulation of the HPA axis in response to this test. In a second study, we tested the influence of palatable solutions to reduce SD‐stimulated HPA axis activity. Although SD continued to result in high adrenocorticotropic hormone (ACTH) and corticosterone (CORT) plasma levels, animals provided with saccharin or sucrose (palatable) solutions exhibited lower hormone levels than those provided with water. Despite the fact that sleep‐deprived rats consumed a large amount of sucrose solution, they still consumed more chow than their control counterparts and lost just as much weight as the water‐provided sleep‐deprived group, indicating augmented energy expenditure. We pursued the mechanisms that could contribute to such an intense metabolic change and found that insulin levels were greatly reduced after SD and remained low after 96h of sleep recovery, whereas CORT levels were elevated at the end of SD and remained so after sleep recovery. Interestingly, the loss of body weight was due to loss of fat mass, but not to protein in the carcass. Finally, we looked at the feeding pattern and immunoreactivity (ir) of CRH and orexin in the hypothalamus of sleep‐deprived rats. The results showed that sleep‐deprived rats ate more during the daytime than control rats, ACTH and CORT levels were higher than in control rats throughout the entire period of SD and that both CRH and orexin‐ir were increased. The loss of body weight appeared to be related to elevated CORT levels, insofar as chronic administration of metyrapone (a CORT synthesis inhibitor) prevented this phenomenon. In conclusion, this set of data suggests that SD activates the HPA axis in its entirety, despite the modulatory influence of environmental factors. In addition, increased orexin‐ir appears to be involved with both stress and feeding responses induced by SD.Financial support provided by grants from Fundação de Amparo àPesquisa do Estado de São Paulo (FAPESP ‐ CEPID 98/14303‐3) and from Associação Fundo de Incentivo àPsicofarmacologia (AFIP).
Chromatin assembly factors and the challenges of DNA replication and repair
Authors: Almouzni Geneviève 
Published: June 2021

Inheritance and maintenance of the DNA sequence and its organization into chromatin are central for eukaryotic life. To orchestrate DNA‐replication and ‐repair processes in the context of chromatin is a challenge.Factors have been isolated from cell extracts that stimulate early steps in chromatin assembly in vitro. One such factor, chromatin assembly factor‐1 (CAF‐1), facilitates nucleosome formation coupled to DNA synthesis. It is thought to participate in a marking system at the crossroads of DNA replication and repair to monitor genome integrity and to define particular epigenetic states. We have now identified a chromatin assembly pathway independent of DNA synthesis involving the HIRA protein. Notably, CAF‐1 is part of the histone H3 complex, H3.1 complex (replicative form) and HIRA of the H3.3 complex (replacement form) (Tagami et al, 2004, Nakatani et al, 2004). In addition, another histone chaperone, Asf1, has to be integrated in a network of interactions leading to nucleosome deposition. A major goal in our laboratory is now to better integrate the function of these factors in vivo during development and also in connection with replication, repair and control of histone pools.We will discuss our recent findings on this topics and the interrelationships with other assembly factors.
Wnt7a is up‐regulated in mice with heritable misexpression of Six2 associated with frontonasal dysplasia
Authors: Hynd T.J. , Fong Keith S. K. , Fogelgren Ben , Kuroyama Mari , Lozanoff Scott 
Published: June 2021

Wnts are secreted glycoproteins involved in an array of developmental processes. In facial morphogenesis, Wnts appear to mediate development of the midface and fusion of the upper lip. We have previously described the Br mutant mouse displaying heritable frontonasal dysplasia (FND). Linkage analysis mapped the Br mutation near the homeobox transcription factor Six2, normally expressed in the facial mesenchyme during embryonic development. The purpose of this study is to determine possible upstream and downstream events of Six2, notably in the Wnt signaling pathway, leading to FND. Frontal nasal prominences (FNP) of E11.5 embryos were dissected and RNA extracted via Qiagen's RNeasy Mini Kit. Total RNA was reverse transcribed using Bio‐Rad's iScript cDNA Synthesis Kit. qRT‐PCR reactions were performed with SYBR Green Supermix and novel primers for Six2 and SABiosciences RT² Profiler PCR Array for Wnt signaling pathway molecules. The MyiQ iCycler thermocycler and single color real‐time PCR detection system (Bio‐Rad) were also used. Results suggest Six2 is expressed in a haploinsufficient pattern in the FNP. Additional data indicates Wnt7a expression is up‐regulated three‐fold in the Br/Br mutant. These data suggest Six2 may down‐regulate Wnt7a in the face and in the absence of suppression, Wnt7a may prevent further differentiation of midfacial structures resulting in FND. Further work will be necessary to determine specific downstream targets of Six2. Supported by R0‐1 DK064752 (SL).Grant Funding SourceNIH
Penetration of Fluorescent Nanospheres through the Canine Zona Pellucida
Authors: Lunn Matthew O. , Wright Shirley J. 
Published: June 2021

Mammalian oocytes are surrounded by an extracellular glycoprotein matrix called the zona pellucida (ZP). Sperm bind and penetrate the ZP to fertilize the oocyte. ZP structure and composition varies depending on the species. Surprisingly little is known about the ultrastructure of the ZP in companion animals. Our previous studies have shown the canine ZP is porous. The objective of this study was to determine whether the canine ZP prevents nanospheres the size of canine viruses from penetrating the ZP. Oocytes (n = 184) were isolated from ovaries from 21 dogs aged 6 months to 9 years. Oocytes were exposed to fluorescent nanospheres (24, 100, 210 nm), and confocal microscopy was used to determine how far the nanospheres penetrated the ZP. The 210 nm nanospheres penetrated the entire width of the ZP in only 24.6% of the oocytes (n = 57), whereas the 100 nm and the 24 nm nanospheres penetrated the ZP more often, 41.5% (n = 53 oocytes) and 86.3% (n = 74 oocytes), respectively. In some oocytes, most of the ZP was resistant to penetration, however, the nanospheres penetrated the ZP in discrete patches reminiscent of the path of transzonal processes of cumulus cells. Since the ZP inconsistently blocks nanospheres, in vitro fertilization is not a means to consistently produce viable, virus‐free offspring from infected dogs and endangered canids.Grant Funding SourceAKC Canine Health Foundation
Shunt revisions effect on frontal occipital horn ratio‐an anatomic study
Authors: Osuagwu Ferdnand Chisom , Lazareff Jorge 
Published: June 2021

BackgroundVentricular volume estimates can be challenging if dealing with multiple imaging modalities. Frontal and occipital horn ratio has been described as a simple linear measurement that correlates well with ventricular volume estimates. Multiple shunt revisions have been associated with potential changes in ventricular volumes.We aimed our study at determining the association between multiple shunt revisions with distal slit valve and evaluated the effect on the frontal‐occipital horn ratio (FOR).Materials and MethodsWe compared the frontal and occipital horn ratio in 16 children with one or more ventriculoperitoneal shunts insertion with distal slit valves.ResultsThe mean frontal‐occipital horn ratio in all groups was 0.55±0.04.The mean frontal‐occipital horn ratio for the patients shunted once (n=2) was 0.48±0.02, the patients shunted twice (n=3) was 0.56±0.03, the patients shunted thrice (n=5) was 0.55±0.04, the patients shunted four times (n=5) had a value of 0.56±0.02 while the patient who was shunted five times (n=1) had an FOR value of 0.57.ConclusionThe frontal and occipital horn ratio did not exhibit much change if two or more shunt revisions are conducted.Grant Funding SourceNone
The Use of Team Process Framework to Improve Small Group Learning
Authors: Khalil Mohammed K , Johnson Tristan E , Spector J. Michael , Payer Andrew F 
Published: June 2021

Working in teams is an important aspect of clinical practice and medical education. Medical educators have embraced instructional strategies that use multiple learners to facilitate learning. However, the learning benefits of these strategies should be substantiated by additional inquiries in the area of team cognition and team processes. There are limited efforts to evaluate the efficacy of learning processes associated with learning teams. This presentation provides theoretical background for team learning processes that influence team and individual learning. It also outlines the development of shared understanding or shared mental models, and how they impact students' performance. Team process behaviors, such as team communication and team coordination, mediate the process of developing shared mental models, which in turn affect learning outcomes. Understanding the role of shared mental models in small group learning improves the efficacy of small group learning.Grant Funding SourceN/A
A hydrophobic patch on proteinase 3, the target of autoantibodies in Wegener's granulomatosis, mediates membrane binding via NB1 receptors
Authors: Korkmaz Brice , Kuhl Angelika , Bayat Behnaz , Santoso Sentot , Jenne Dieter E. 
Published: June 2021

Proteinase 3 (PR3), the target antigen of antineutrophil cytoplasmic antibodies which are found in patients with Wegener's granulomatosis, is a neutrophil serine protease localized within cytoplasmic granules. A small fraction of it is translocated to the plasma membrane of neutrophils after cytokine priming. Recently, the human neutrophil antigen NB1 was identified as a specific neutrophil cell surface receptor of PR3. We hypothesized that the unique hydrophobic cluster of PR3 that is not present in other PR3 homologs accounts for its binding to the NB1 receptor expressed on the cellular surface of NB1 expressing cells. Instead of generating and testing various artificial human PR3 mutants, we cloned and expressed the very closely related gibbon (Hylobates pileatus) PR3 homolog which did not bind to the human NB1 receptor. Moreover, a human‐gibbon hybrid constructed from the N‐ and C‐terminal half of the human and gibbon PR3, respectively, did also not interact with human NB1. The C‐terminal half of gibbon PR3 differs only by 9 residues from human PR3, among which four closely spaced hydrophobic residues are substituted in a non conservative manner (Phe166Leu, Trp218Arg, Gly219Ala, Leu223His). The NB1 bound PR3 was active and was rapidly cleared from the surface by alpha‐1‐protease inhibitor (a1‐PI).Deutsche Forschungsgemeinschaft (SFB 571)