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Williams JA, Kao JY, Omary MB. How Can Individuals and the GI Community Reduce Climate Change? Gastroenterology 2020; 158:14-17. [PMID: 31626756 DOI: 10.1053/j.gastro.2019.10.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 10/02/2019] [Indexed: 12/02/2022]
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Williams JA, Powell G, Mallon AM, Simon MM. Genomic Mutation Identification in Mice Using Illumina Sequencing and Linux-Based Computational Methods. ACTA ACUST UNITED AC 2019; 9:e64. [PMID: 31532925 DOI: 10.1002/cpmo.64] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Genetically modified mice are an essential tool for modeling disease-causing mechanisms and discovering gene function. SNP genotyping was traditionally used to associate candidate regions with traits in the mouse, but failed to reveal novel variants without further targeted sequencing. Using a robust set of computational protocols, we present a platform to enable scientists to detect variants arising from whole-genome and exome sequencing experiments. This article guides researchers on aligning reads to the mouse genome, quality-assurance strategies, mutation discovery, comparing mutations to previously discovered mouse SNPs, and the annotation of novel variants, in order to predict mutation consequences on the protein level. Challenges unique to the mouse are discussed, and two protocols use self-contained containers to maintain version control and allow users to adapt our approach to new techniques by upgrading container versions. Our protocols are suited for servers or office workstations and are usable by non-bioinformatics specialists. © 2019 by John Wiley & Sons, Inc.
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Bravo-Merodio L, Williams JA, Gkoutos GV, Acharjee A. -Omics biomarker identification pipeline for translational medicine. J Transl Med 2019; 17:155. [PMID: 31088492 PMCID: PMC6518609 DOI: 10.1186/s12967-019-1912-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Accepted: 05/08/2019] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Translational medicine (TM) is an emerging domain that aims to facilitate medical or biological advances efficiently from the scientist to the clinician. Central to the TM vision is to narrow the gap between basic science and applied science in terms of time, cost and early diagnosis of the disease state. Biomarker identification is one of the main challenges within TM. The identification of disease biomarkers from -omics data will not only help the stratification of diverse patient cohorts but will also provide early diagnostic information which could improve patient management and potentially prevent adverse outcomes. However, biomarker identification needs to be robust and reproducible. Hence a robust unbiased computational framework that can help clinicians identify those biomarkers is necessary. METHODS We developed a pipeline (workflow) that includes two different supervised classification techniques based on regularization methods to identify biomarkers from -omics or other high dimension clinical datasets. The pipeline includes several important steps such as quality control and stability of selected biomarkers. The process takes input files (outcome and independent variables or -omics data) and pre-processes (normalization, missing values) them. After a random division of samples into training and test sets, Least Absolute Shrinkage and Selection Operator and Elastic Net feature selection methods are applied to identify the most important features representing potential biomarker candidates. The penalization parameters are optimised using 10-fold cross validation and the process undergoes 100 iterations and a combinatorial analysis to select the best performing multivariate model. An empirical unbiased assessment of their quality as biomarkers for clinical use is performed through a Receiver Operating Characteristic curve and its Area Under the Curve analysis on both permuted and real data for 1000 different randomized training and test sets. We validated this pipeline against previously published biomarkers. RESULTS We applied this pipeline to three different datasets with previously published biomarkers: lipidomics data by Acharjee et al. (Metabolomics 13:25, 2017) and transcriptomics data by Rajamani and Bhasin (Genome Med 8:38, 2016) and Mills et al. (Blood 114:1063-1072, 2009). Our results demonstrate that our method was able to identify both previously published biomarkers as well as new variables that add value to the published results. CONCLUSIONS We developed a robust pipeline to identify clinically relevant biomarkers that can be applied to different -omics datasets. Such identification reveals potentially novel drug targets and can be used as a part of a machine-learning based patient stratification framework in the translational medicine settings.
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Williams JA. Cholecystokinin (CCK) Regulation of Pancreatic Acinar Cells: Physiological Actions and Signal Transduction Mechanisms. Compr Physiol 2019; 9:535-564. [PMID: 30873601 DOI: 10.1002/cphy.c180014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Pancreatic acinar cells synthesize and secrete about 20 digestive enzymes and ancillary proteins with the processes that match the supply of these enzymes to their need in digestion being regulated by a number of hormones (CCK, secretin and insulin), neurotransmitters (acetylcholine and VIP) and growth factors (EGF and IGF). Of these regulators, one of the most important and best studied is the gastrointestinal hormone, cholecystokinin (CCK). Furthermore, the acinar cell has become a model for seven transmembrane, heterotrimeric G protein coupled receptors to regulate multiple processes by distinct signal transduction cascades. In this review, we briefly describe the chemistry and physiology of CCK and then consider the major physiological effects of CCK on pancreatic acinar cells. The majority of the review is devoted to the physiologic signaling pathways activated by CCK receptors and heterotrimeric G proteins and the functions they affect. The pathways covered include the traditional second messenger pathways PLC-IP3-Ca2+ , DAG-PKC, and AC-cAMP-PKA/EPAC that primarily relate to secretion. Then there are the protein-protein interaction pathways Akt-mTOR-S6K, the three major MAPK pathways (ERK, JNK, and p38 MAPK), and Ca2+ -calcineurin-NFAT pathways that primarily regulate non-secretory processes including biosynthesis and growth, and several miscellaneous pathways that include the Rho family small G proteins, PKD, FAK, and Src that may regulate both secretory and nonsecretory processes but are not as well understood. © 2019 American Physiological Society. Compr Physiol 9:535-564, 2019.
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Park MJ, Iyer S, Xue X, Cunha JB, Gu S, Moons D, Pipe SW, Williams JA, Simeone DM, Shah YM, Omary MB. HIF1-alpha Regulates Acinar Cell Function and Response to Injury in Mouse Pancreas. Gastroenterology 2018; 154:1630-1634.e3. [PMID: 29409830 PMCID: PMC5927829 DOI: 10.1053/j.gastro.2018.01.037] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 01/02/2018] [Accepted: 01/19/2018] [Indexed: 12/28/2022]
Abstract
We investigated whether intrapancreatic coagulation, with deposition of the fibrinogen-γ dimer (Fib-γD) and hypoxia, affect the severity of acute pancreatitis (AP) in mice. Pancreata of mice with AP induced by administration of cerulein or by L-arginine, or from patients with pancreatitis, had increased deposition of Fib-γD compared with control pancreata. Heparin administration protected mice from cerulein-induced AP and prevented Fib-γD formation. Cerulein administration resulted in activation and stabilization of hypoxia-inducible factor-1α (HIF1α) in pancreata of oxygen-dependent degradation domain-luciferase HIF1α reporter mice. Cerulein also led to induction of genes regulated by HIF1α, including Vegfa and Ero1a, before evidence of Fib-γD deposition or histologic features of AP. Expression of tissue factor, which is regulated by vascular endothelial growth factor, also increased following cerulein administration. Mice with acinar cell-specific disruption of Hif1a (Hif1aAc-/-) developed spontaneous endoplasmic reticulum stress and less severe AP, but did not accumulate Fib-γD following administration of cerulein. Feeding mice increased pancreatic expression of HIF1α, indicating a physiologic role in the exocrine pancreas. Therefore, HIF1α has bifunctional roles, in exocrine pancreas homeostasis and progression of AP that is promoted by intrapancreatic coagulation.
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Elenbaas JS, Cunha JB, Azuero-Dajud R, Nelson B, Oral EA, Williams JA, Stewart CL, Omary MB. Lamin A/C Maintains Exocrine Pancreas Homeostasis by Regulating Stability of RB and Activity of E2F. Gastroenterology 2018; 154:1625-1629.e8. [PMID: 29366840 PMCID: PMC5927841 DOI: 10.1053/j.gastro.2018.01.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 11/29/2017] [Accepted: 01/09/2018] [Indexed: 12/18/2022]
Abstract
Lamins have important roles in nuclear structure and cell signaling. Several diseases are associated with mutations in the lamin A/C gene (LMNA in humans). Patients with familial partial lipodystrophy caused by LMNA mutations develop pancreatitis, but lamin function in the pancreas and how these mutations affect pancreatic regulation are unknown. We generated mice with inducible exocrine pancreas-specific disruption of Lmna and showed that LMNA is lost from most exocrine pancreas cells. LMNA-knockout pancreata develop endoplasmic reticulum stress with loss of acinar cell markers, increased autophagy, apoptosis, and cell proliferation, compared to CreERT2- mice (littermate controls). Disruption of Lmna led to a phenotype that resembled chronic pancreatitis, with increased Sirius Red staining and α-smooth muscle actin in male LMNA-knockout mice compared to littermate males, but not in female mice. LMNA-knockout pancreata have reduced levels of RB and activation of E2F, based on increased expression of E2F target genes. Therefore, lamins maintain pancreatic homeostasis by regulating RB stability and E2F activity.
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Williams JA, Yule DI. Can pancreatitis be treated by inhibiting Ca 2+ signaling? ANNALS OF TRANSLATIONAL MEDICINE 2018; 6:124. [PMID: 29955584 DOI: 10.21037/atm.2017.06.07] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Khoriaty R, Vogel N, Hoenerhoff MJ, Sans MD, Zhu G, Everett L, Nelson B, Durairaj H, McKnight B, Zhang B, Ernst SA, Ginsburg D, Williams JA. SEC23B is required for pancreatic acinar cell function in adult mice. Mol Biol Cell 2017; 28:2146-2154. [PMID: 28539403 PMCID: PMC5509426 DOI: 10.1091/mbc.e17-01-0001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 05/08/2017] [Accepted: 05/19/2017] [Indexed: 12/27/2022] Open
Abstract
Inactivation of Sec23b exclusively in the pancreatic acinar cells of adult mice results in loss of pancreatic mass, with evidence of cell loss, degeneration of exocrine cells (with smaller-than-normal zymogen granules and ER dilation), ER stress, and increased pancreatic cell apoptosis. Mice with germline absence of SEC23B die perinatally, exhibiting massive pancreatic degeneration. We generated mice with tamoxifen-inducible, pancreatic acinar cell–specific Sec23b deletion. Inactivation of Sec23b exclusively in the pancreatic acinar cells of adult mice results in decreased overall pancreatic weights from pancreatic cell loss (decreased pancreatic DNA, RNA, and total protein content), as well as degeneration of exocrine cells, decreased zymogen granules, and alterations in the endoplasmic reticulum (ER), ranging from vesicular ER to markedly expanded cisternae with accumulation of moderate-density content or intracisternal granules. Acinar Sec23b deletion results in induction of ER stress and increased apoptosis in the pancreas, potentially explaining the loss of pancreatic cells and decreased pancreatic weight. These findings demonstrate that SEC23B is required for normal function of pancreatic acinar cells in adult mice.
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Spicer LJ, Schütz LF, Williams JA, Schreiber NB, Evans JR, Totty ML, Gilliam JN. G protein-coupled receptor 34 in ovarian granulosa cells of cattle: changes during follicular development and potential functional implications. Domest Anim Endocrinol 2017; 59:90-99. [PMID: 28040605 PMCID: PMC5357439 DOI: 10.1016/j.domaniend.2016.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 11/30/2016] [Accepted: 12/01/2016] [Indexed: 01/08/2023]
Abstract
Abundance of G protein-coupled receptor 34 (GPR34) mRNA is greater in granulosa cells (GCs) of cystic vs normal follicles of cattle. The present experiments were designed to determine if GPR34 mRNA in granulosa cell [GC] changes during selection and growth of dominant follicles in cattle as well as to investigate the hormonal regulation of GPR34 mRNA in bovine GC in vitro. In Exp. 1, estrous cycles of nonlactating cows were synchronized and then ovariectomized on either day 3-4 or 5-6 after ovulation. GPR34 mRNA abundance in GC was 2.8- to 3.8-fold greater (P < 0.05) in small (1-5 mm) and large (≥8 mm) estrogen-inactive dominant follicles than in large estrogen-active follicles. Also, GPR34 mRNA tended to be greater (P < 0.10) in F2 than F1 follicles on day 3-4 postovulation. In Exp. 2-7, ovaries were collected at an abattoir and GC were isolated and treated in vitro. Expression of GPR34 was increased (P < 0.05) 2.2-fold by IGF1. Tumor necrosis factor (TNF)-α decreased (P < 0.05) the IGF1-induced GPR34 mRNA abundance in small-follicle GC, whereas IGF1 decreased (P < 0.05) GPR34 expression by 45% in large-follicle GC. Treatment of small-follicle GC with either IL-2, prostaglandin E2 or angiogenin decreased (P < 0.05) GPR34 expression, whereas FSH, cortisol, wingless 3A, or hedgehog proteins did not affect (P > 0.10) GPR34 expression. In Exp. 6 and 7, 2 presumed ligands of GPR34, L-a-lysophosphatidylserine (LPPS) and LPP-ethanolamine, increased (P < 0.05) GC numbers and estradiol production by 2-fold or more in small-follicle GC, and this response was only observed in IGF1-treated GC. In conclusion, GPR34 is a developmentally and hormonally regulated gene in GC, and its presumed ligands enhance IGF1-induced proliferation and steroidogenesis of bovine GC.
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Scheerens H, Malong A, Bassett K, Boyd Z, Gupta V, Harris J, Mesick C, Simnett S, Stevens H, Gilbert H, Risser P, Kalamegham R, Jordan J, Engel J, Chen S, Essioux L, Williams JA. Current Status of Companion and Complementary Diagnostics: Strategic Considerations for Development and Launch. Clin Transl Sci 2017; 10:84-92. [PMID: 28121072 PMCID: PMC5355969 DOI: 10.1111/cts.12455] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 01/18/2017] [Indexed: 02/06/2023] Open
Abstract
US Food and Drug Administration (FDA)‐approved diagnostic assays play an increasingly common role in managing patients to prolong lifespan while also enhancing quality of life. Diagnostic assays can be essential for the safe and effective use of therapeutics (companion diagnostic), or may inform on improving the benefit/risk ratio without restricting drug access (complementary diagnostic). This tutorial reviews strategic considerations for drug and assay development resulting in FDA‐approved companion or complementary diagnostic status.
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Li C, A. Williams J. Regulation of CCK-induced ERK1/2 activation by PKC epsilon in rat pancreatic acinar cells. AIMS MOLECULAR SCIENCE 2017. [DOI: 10.3934/molsci.2017.4.463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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Kang MH, Prieto López LO, Chen B, Teo K, Williams JA, Milne WI, Cole MT. Mechanical Robustness of Graphene on Flexible Transparent Substrates. ACS APPLIED MATERIALS & INTERFACES 2016; 8:22506-22515. [PMID: 27482734 DOI: 10.1021/acsami.6b06557] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This study reports on a facile and widely applicable method of transferring chemical vapor deposited (CVD) graphene uniformly onto optically transparent and mechanically flexible substrates using commercially available, low-cost ultraviolet adhesive (UVA) and hot-press lamination (HPL). We report on the adhesion potential between the graphene and the substrate, and we compare these findings with those of the more commonly used cast polymer handler transfer processes. Graphene transferred with the two proposed methods showed lower surface energy and displayed a higher degree of adhesion (UVA: 4.40 ± 1.09 N/m, HPL: 0.60 ± 0.26 N/m) compared to equivalent CVD-graphene transferred using conventional poly(methyl methacrylate) (PMMA: 0.44 ± 0.06 N/m). The mechanical robustness of the transferred graphene was investigated by measuring the differential resistance as a function of bend angle and repeated bend-relax cycles across a range of bend radii. At a bend angle of 100° and a 2.5 mm bend radius, for both transfer techniques, the normalized resistance of graphene transferred on polyethylene terephthalate (PET) was around 80 times less than that of indium-tin oxide on PET. After 10(4) bend cycles, the resistance of the transferred graphene on PET using UVA and HPL was found to be, on average, around 25.5 and 8.1% higher than that of PMMA-transferred graphene, indicating that UVA- and HPL-transferred graphene are more strongly adhered compared to PMMA-transferred graphene. The robustness, in terms of maintained electrical performance upon mechanical fatigue, of the transferred graphene was around 60 times improved over ITO/PET upon many thousands of repeated bending stress cycles. On the basis of present production methods, the development of the next-generation of highly conformal, diverse form factor electronics, exploiting the emerging family of two-dimensional materials, necessitates the development of simple, low-cost, and mechanically robust transfer processes; the developed UVA and HPL approaches show significant potential and allow for large-area-compatible, near-room temperature transfer of graphene onto a diverse range of polymeric supports.
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Simonelli M, Zucali P, Santoro A, Thomas MB, de Braud FG, Borghaei H, Berlin J, Denlinger CS, Noberasco C, Rimassa L, Kim TY, English PA, Abbattista A, Gallo Stampino C, Carpentieri M, Williams JA. Phase I study of PF-03446962, a fully human monoclonal antibody against activin receptor-like kinase-1, in patients with hepatocellular carcinoma. Ann Oncol 2016; 27:1782-7. [PMID: 27329247 DOI: 10.1093/annonc/mdw240] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 06/09/2016] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND This expansion cohort of a multicenter, dose-escalation, phase I study (NCT00557856) evaluated safety, tolerability, antitumor activity, pharmacokinetics, and pharmacodynamic effects of the anti-activin receptor-like kinase-1 (ALK-1) monoclonal antibody PF-03446962 in advanced hepatocellular carcinoma (HCC). PATIENTS AND METHODS Patients with HCC and disease progression after prior antiangiogenic therapy or intolerance to treatment received PF-03446962 7 mg/kg intravenously biweekly, as recommended in the dose-escalation part of the study. RESULTS Twenty-four patients received PF-03446962. The most frequent treatment-related adverse events (AEs) were thrombocytopenia (33.3%), asthenia (29.2), and chills (16.7%). Two patients experienced treatment-related telangiectasia, suggesting an in vivo knockout of ALK-1 function through ALK-1 pathway inhibition. Overall, treatment-related grade 3-4 AEs were reported in eight patients (33.3%). Treatment-related grade 3-4 thrombocytopenia was noted in four patients. No complete or partial responses were reported. Twelve (50%) patients achieved stable disease, which lasted ≥12 weeks in seven (29.2%) patients. The median time to progression was 3 months. Biomarker analyses showed higher mean tumor expression of c-tumor mesenchymal-epithelial transition factor and higher mean serum levels of bone morphogenetic protein-9 in patients with disease control (DC) for ≥12 weeks versus patients with disease progression. Conversely, lower mean serum transforming growth factor-β and vascular endothelial growth factor receptor-3 levels were detected in patients with DC versus patients with progression. CONCLUSIONS The observed safety, tolerability, pharmacokinetic profile, and clinical activity support further evaluation of PF-03446962 in patients with HCC and other solid malignancies, as single agent or in combination with other antiangiogenic, chemotherapeutic, or immunotherapeutic agents. TRIAL REGISTRATION NUMBER NCT00557856.
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Aria A, Kidambi PR, Weatherup RS, Xiao L, Williams JA, Hofmann S. Time Evolution of the Wettability of Supported Graphene under Ambient Air Exposure. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2016; 120:2215-2224. [PMID: 26900413 PMCID: PMC4754094 DOI: 10.1021/acs.jpcc.5b10492] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 01/07/2016] [Indexed: 05/08/2023]
Abstract
The wettability of graphene is both fundamental and crucial for interfacing in most applications, but a detailed understanding of its time evolution remains elusive. Here we systematically investigate the wettability of metal-supported, chemical vapor deposited graphene films as a function of ambient air exposure time using water and various other test liquids with widely different surface tensions. The wettability of graphene is not constant, but varies with substrate interactions and air exposure time. The substrate interactions affect the initial graphene wettability, where, for instance, water contact angles of ∼85 and ∼61° were measured for Ni and Cu supported graphene, respectively, after just minutes of air exposure. Analysis of the surface free energy components indicates that the substrate interactions strongly influence the Lewis acid-base component of supported graphene, which is considerably weaker for Ni supported graphene than for Cu supported graphene, suggesting that the classical van der Waals interaction theory alone is insufficient to describe the wettability of graphene. For prolonged air exposure, the effect of physisorption of airborne contaminants becomes increasingly dominant, resulting in an increase of water contact angle that follows a universal linear-logarithmic relationship with exposure time, until saturating at a maximum value of 92-98°. The adsorbed contaminants render all supported graphene samples increasingly nonpolar, although their total surface free energy decreases only by 10-16% to about 37-41 mJ/m2. Our finding shows that failure to account for the air exposure time may lead to widely different wettability values and contradicting arguments about the wetting transparency of graphene.
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Hou Y, Ernst SA, Lentz SI, Williams JA. Genetic deletion of Rab27B in pancreatic acinar cells affects granules size and has inhibitory effects on amylase secretion. Biochem Biophys Res Commun 2016; 471:610-5. [PMID: 26845357 DOI: 10.1016/j.bbrc.2016.01.180] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 01/29/2016] [Indexed: 11/26/2022]
Abstract
Small G protein Rab27B is expressed in various secretory cell types and plays a role in mediating secretion. In pancreatic acinar cells, Rab27B was found to be expressed on the zymogen granule membrane and by overexpression to regulate the secretion of zymogen granules. However, the effect of Rab27B deletion on the physiology of pancreatic acinar cells is unknown. In the current study, we utilized the Rab27B KO mouse model to better understand the role of Rab27B in the secretion of pancreatic acinar cells. Our data show that Rab27B deficiency had no obvious effects on the expression of major digestive enzymes and other closely related proteins, e.g. similar small G proteins, such as Rab3D and Rab27A, and putative downstream effectors. The overall morphology of acinar cells was not changed in the knockout pancreas. However, the size of zymogen granules was decreased in KO acinar cells, suggesting a role of Rab27B in regulating the maturation of secretory granules. The secretion of digestive enzymes was moderately decreased in KO acini, compared with the WT control. These data indicate that Rab27B is involved at a different steps of zymogen granule maturation and secretion, which is distinct from that of Rab3D.
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Hou Y, Ernst SA, Heidenreich K, Williams JA. Glucagon-like peptide-1 receptor is present in pancreatic acinar cells and regulates amylase secretion through cAMP. Am J Physiol Gastrointest Liver Physiol 2016; 310:G26-33. [PMID: 26542397 PMCID: PMC4698438 DOI: 10.1152/ajpgi.00293.2015] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 10/27/2015] [Indexed: 01/31/2023]
Abstract
Glucagon-like peptide-1 (GLP-1) is a glucoincretin hormone that can act through its receptor (GLP-1R) on pancreatic β-cells and increase insulin secretion and production. GLP-1R agonists are used clinically to treat type 2 diabetes. GLP-1 may also regulate the exocrine pancreas at multiple levels, including inhibition through the central nervous system, stimulation indirectly through insulin, and stimulation directly on acinar cells. However, it has been unclear whether GLP-1R is present in pancreatic acini and what physiological functions these receptors regulate. In the current study we utilized GLP-1R knockout (KO) mice to study the role of GLP-1R in acinar cells. RNA expression of GLP-1R was detected in acutely isolated pancreatic acini. Acinar cell morphology and expression of digestive enzymes were not affected by loss of GLP-1R. GLP-1 induced amylase secretion in wild-type (WT) acini. In GLP-1R KO mice, this effect was abolished, whereas vasoactive intestinal peptide-induced amylase release in KO acini showed a pattern similar to that in WT acini. GLP-1 stimulated cAMP production and increased protein kinase A-mediated protein phosphorylation in WT acini, and these effects were absent in KO acini. These data show that GLP-1R is present in pancreatic acinar cells and that GLP-1 can regulate secretion through its receptor and cAMP signaling pathway.
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Abstract
BACKGROUND Glucagon Like Peptide 1 (GLP-1) mimetic drugs or degradation inhibitors mimic the action of native GLP-1 as a incretin hormone and have become a common second line of therapy for Type 2 diabetes. However, an important clinical issue is whether these drugs increase the incidence of pancreatitis and pancreatic cancer. OBJECTIVE This paper reviews the physiology of GLP-1 including its synthesis, secretion and action of the peptide. Reported effects of the mimetic drugs on the exocrine pancreas in animal studies are also reviewed. RESULTS GLP-1 is synthesized in a specific class of enteroendocrine cell, the L-cell, by post-translational processing of proglucagon. It is released in response to the presence of nutrients in the small intestine and stimulates vagal afferent nerve endings as well as entering the blood where it is rapidly degraded by dipeptidyl peptidase IV. Its actions are mediated by specific G-protein coupled receptors. The major target tissues are the pancreatic islet beta cells, the brain and the heart but GLP-1 also affects gastrointestinal motility and secretion including the exocrine pancreas where its major systemic action is to inhibit secretion. In some animal, as well as human studies, the GLP-1 mimetic drugs are associated with pancreatitis or precursor lessions to pancreatic cancer but a mechanism is not clear. The most common occurrence of pathology in rodents is when the drugs are combined with a high fat diet. CONCLUSIONS There is nothing in the physiology of GLP-1 or animal toxicology studies to support a mechanism of action or a major concern about the action of GLP-1 mimetic drugs on the exocrine pancreas. Further studies are warranted using animal models of disease and high fat diets.
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Kang YK, Yau T, Park JW, Lim HY, Lee TY, Obi S, Chan SL, Qin S, Kim RD, Casey M, Chen C, Bhattacharyya H, Williams JA, Valota O, Chakrabarti D, Kudo M. Randomized phase II study of axitinib versus placebo plus best supportive care in second-line treatment of advanced hepatocellular carcinoma. Ann Oncol 2015; 26:2457-63. [PMID: 26386123 DOI: 10.1093/annonc/mdv388] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 09/10/2015] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The efficacy and safety of axitinib, a potent and selective vascular endothelial growth factor receptors 1-3 inhibitor, combined with best supportive care (BSC) was evaluated in a global, randomized, placebo-controlled phase II trial in patients with locally advanced or metastatic hepatocellular carcinoma (HCC). PATIENTS AND METHODS Patients with HCC and Child-Pugh Class A who progressed on or were intolerant to one prior antiangiogenic therapy were stratified by tumour invasion (presence/absence of extrahepatic spread and/or vascular invasion) and region (Asian/non-Asian) and randomized (2:1) to axitinib/BSC (starting dose 5 mg twice-daily) or placebo/BSC. The primary end point was overall survival (OS). RESULTS The estimated hazard ratio for OS was 0.907 [95% confidence interval (CI) 0.646-1.274; one-sided stratified P = 0.287] for axitinib/BSC (n = 134) versus placebo/BSC (n = 68), with the median (95% CI) of 12.7 (10.2-14.9) versus 9.7 (5.9-11.8) months, respectively. Results of prespecified subgroup analyses in Asian versus non-Asian patients or presence versus absence of tumour invasion were consistent with the overall population. Improvements favouring axitinib/BSC (P < 0.01) were observed in secondary efficacy end point analyses [progression-free survival (PFS), time to tumour progression (TTP), and clinical benefit rate (CBR)], and were retained among Asian patients in the prespecified subgroup analyses. Overall response rate did not differ significantly between treatments and patient-reported outcomes favoured placebo/BSC. Most common all-causality adverse events with axitinib/BSC were diarrhoea (54%), hypertension (54%), and decreased appetite (47%). Baseline serum analyses identified potential new prognostic (interleukin-6, E-selectin, interleukin-8, angiopoietin-2, migration inhibitory factor, and c-MET) or predictive (E-selectin and stromal-derived factor-1) factors for survival. CONCLUSIONS Axitinib/BSC did not improve OS over placebo/BSC in the overall population or in stratification subgroups. However, axitinib/BSC resulted in significantly longer PFS and TTP and higher CBR, with acceptable toxicity in patients with advanced HCC. TRIAL REGISTRATION ClinicalTrials.gov, NCT01210495.
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Holtz BJ, Lodewyk KB, Sebolt-Leopold JS, Ernst SA, Williams JA. ERK activation is required for CCK-mediated pancreatic adaptive growth in mice. Am J Physiol Gastrointest Liver Physiol 2014; 307:G700-10. [PMID: 25104499 PMCID: PMC4187068 DOI: 10.1152/ajpgi.00163.2014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
High levels of cholecystokinin (CCK) can stimulate pancreatic adaptive growth in which mature acinar cells divide, leading to enhanced pancreatic mass with parallel increases in protein, DNA, RNA, and digestive enzyme content. Prolonged release of CCK can be induced by feeding trypsin inhibitor (TI) to disrupt normal feedback control. This leads to exocrine growth in a CCK-dependent manner. The extracellular signal-related kinase (ERK) pathway regulates many proliferative processes in various tissues and disease models. The aim of this study was to evaluate the role of ERK signaling in pancreatic adaptive growth using the MEK inhibitors PD-0325901 and trametinib (GSK-1120212). It was determined that PD-0325901 given two times daily by gavage or mixed into powdered chow was an effective and specific inhibitor of ERK signaling in vivo. TI-containing chow led to a robust increase in pancreatic mass, protein, DNA, and RNA content. This pancreatic adaptive growth was blocked in mice fed chow containing the MEK inhibitors. PD-0325901 blocked TI-induced ERK-regulated early response genes, cell-cycle proteins, and mitogenesis by acinar cells. It was determined that ERK signaling is necessary for the initiation of pancreatic adaptive growth but not necessary to maintain it. PD-0325901 blocked adaptive growth when given before cell-cycle initiation but not after mitogenesis had been established. Furthermore, GSK-1120212, a chemically distinct inhibitor of the ERK pathway that is now approved for clinical use, inhibited growth similar to PD-0325901. These data demonstrate that the ERK pathway is required for CCK-stimulated pancreatic adaptive growth.
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Twelves C, Chmielowska E, Havel L, Popat S, Swieboda-Sadlej A, Sawrycki P, Bycott P, Ingrosso A, Kim S, Williams JA, Chen C, Olszanski AJ, de Besi P, Schiller JH. Randomised phase II study of axitinib or bevacizumab combined with paclitaxel/carboplatin as first-line therapy for patients with advanced non-small-cell lung cancer. Ann Oncol 2014; 25:132-8. [PMID: 24356624 DOI: 10.1093/annonc/mdt489] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Efficacy and safety of first-line axitinib/paclitaxel/carboplatin versus bevacizumab/paclitaxel/carboplatin in advanced non-squamous non-small-cell lung cancer (NSCLC) was evaluated. PATIENTS AND METHODS Patients with stage IIIB/IV disease stratified by adjuvant therapy and gender were randomised 1 : 1 to axitinib (5 mg twice daily) or bevacizumab [15 mg/kg every 3 weeks (Q3W)], both with paclitaxel (200 mg/m(2) Q3W)/carboplatin (AUC 6 mg min/ml Q3W). RESULTS The trial was discontinued after preliminary analysis. Median progression-free survival (primary end point) for axitinib (N = 58) and bevacizumab (N = 60), respectively, was 5.7 and 6.1 months [hazard ratio (HR) 1.09, 95% confidence interval (CI) 0.68-1.76; one-sided stratified P = 0.64]; median overall survival was 10.6 and 13.3 months (HR 1.12, 95% CI 0.74-1.69; one-sided stratified P = 0.70). Objective response rates (95% CI) were 29.3% (18.1-42.7) and 43.3% (30.6-56.8), respectively; risk ratio 0.676 (95% CI 0.41-1.11; one-sided stratified P = 0.94). The most common grade 3/4 adverse events included neutropenia (28% versus 20%), fatigue (14% versus 7%), and hypertension (14% versus 5%). Patient-reported outcomes based on the EORTC QLQ-C30 were similar between arms. CONCLUSIONS In patients with advanced non-squamous NSCLC, axitinib/paclitaxel/carboplatin did not improve efficacy versus bevacizumab/paclitaxel/carboplatin, and was less well tolerated.
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Labonte D, Williams JA, Federle W. Surface contact and design of fibrillar ‘friction pads’ in stick insects (
Carausius morosus
): mechanisms for large friction coefficients and negligible adhesion. J R Soc Interface 2014. [DOI: 10.1098/rsif.2014.0192] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Labonte D, Williams JA, Federle W. Surface contact and design of fibrillar 'friction pads' in stick insects (Carausius morosus): mechanisms for large friction coefficients and negligible adhesion. J R Soc Interface 2014; 11:20140034. [PMID: 24554580 PMCID: PMC3973371 DOI: 10.1098/rsif.2014.0034] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Many stick insects and mantophasmids possess tarsal ‘heel pads’ (euplantulae) covered by arrays of conical, micrometre-sized hairs (acanthae). These pads are used mainly under compression; they respond to load with increasing shear resistance, and show negligible adhesion. Reflected-light microscopy in stick insects (Carausius morosus) revealed that the contact area of ‘heel pads’ changes with normal load on three hierarchical levels. First, loading brought larger areas of the convex pads into contact. Second, loading increased the density of acanthae in contact. Third, higher loads changed the shape of individual hair contacts gradually from circular (tip contact) to elongated (side contact). The resulting increase in real contact area can explain the load dependence of friction, indicating a constant shear stress between acanthae and substrate. As the euplantula contact area is negligible for small loads (similar to hard materials), but increases sharply with load (resembling soft materials), these pads show high friction coefficients despite little adhesion. This property appears essential for the pads’ use in locomotion. Several morphological characteristics of hairy friction pads are in apparent contrast to hairy pads used for adhesion, highlighting key adaptations for both pad types. Our results are relevant for the design of fibrillar structures with high friction coefficients but small adhesion.
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Evans JR, Schreiber NB, Williams JA, Spicer LJ. Effects of fibroblast growth factor 9 on steroidogenesis and control of FGFR2IIIc mRNA in porcine granulosa cells. J Anim Sci 2014; 92:511-9. [PMID: 24664559 PMCID: PMC10837796 DOI: 10.2527/jas.2013-6989] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The objectives of this study were to investigate the effects of fibroblast growth factor 9 (FGF9) on hormone-stimulated porcine granulosa cell proliferation and steroid production and to further elucidate the hormonal and developmental control of FGFR2IIIc gene expression in granulosa cells. Porcine ovaries were collected from a local slaughterhouse and granulosa cells were collected from small to medium (1 to 5 mm) follicles for 5 in vitro studies that were conducted. Cells were cultured for 48 h in 5% fetal calf serum plus 5% porcine serum and then treated with various combinations of FSH, IGF-I, FGF9, Sonic hedgehog (SHH), cortisol, PGE2, and/or wingless-type mouse mammary tumor virus integration site family member 5A (WNT5A) in serum-free medium for an additional 24 or 48 h. Medium was collected for analysis of steroid concentration via RIA, or RNA was collected for gene expression analysis of FGFR2IIIc via quantitative reverse transcription PCR. Fibroblast growth factor 9 stimulated (P < 0.05) IGF-I-induced estradiol production in the presence of FSH and testosterone. However, FGF9 had inconsistent effects on progesterone production, stimulating progesterone production in the presence of FSH and testosterone but inhibiting progesterone production in the presence of IGF-I, FSH, and testosterone. Cell numbers were increased (P < 0.05) by FGF9 in the presence of IGF-I and FSH but not in the presence of FSH and absence of IGF-I. For FGFR2IIIc mRNA studies, granulosa cells were treated with FSH, IGF-I, FGF9, SHH, cortisol, PGE2, or WNT5A. Follicle-stimulating hormone alone had no effect (P > 0.10) whereas IGF-I increased (P < 0.05) FGFR2IIIc mRNA abundance. Cortisol, PGE2, SHH, and WNT5A had no effect (P > 0.10) on FGFR2IIIc gene expression whereas FGF9 in the presence of FSH and IGF-I inhibited (P < 0.05) FGFR2IIIc gene expression. In an in vivo study, granulosa cells from large (7 to 14 mm) follicles had greater (P < 0.05) abundance of FGFR2IIIc mRNA than small (1 to 3 mm) or medium (4 to 6 mm) follicles. In conclusion, IGF-I-induced FGFR2IIIc mRNA may be a mechanism for increased responses to FGF9 in FSH plus IGF-I-treated granulosa cells. Fibroblast growth factor 9 and IGF-I may work together as amplifiers of follicular growth and granulosa cell differentiation by stimulating estradiol production and concomitantly stimulating granulosa cell growth in pigs.
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