The Experts below are selected from a list of 1965 Experts worldwide ranked by ideXlab platform
Michael Solursh - One of the best experts on this subject based on the ideXlab platform.
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primary mesenchyme cell migration requires a chondroitin sulfate dermatan sulfate proteoglycan
Developmental Biology, 1991Co-Authors: Mary Constance Lane, Michael SolurshAbstract:Abstract Primary mesenchyme cell migration in the sea urchin embryo is inhibited by sulfate deprivation and exposure to exogenous β- d -Xylosides, two treatments known to disrupt proteoglycan synthesis. We show that in the developing sea urchin, exogenous Xyloside affects the synthesis by the primary mesenchyme cells of a very large, cell surface chondroitin sulfate/dermatan sulfate proteoglycan. This proteoglycan is present in a partially purified fraction that restores migratory ability to defective cells in vitro. The integrity of this chondroitin sulfate/dermatan sulfate proteoglycan appears essential for primary mesenchyme cell migration since treatment of actively migrating cells with chondroitinase ABC reversibly inhibited their migration in vitro.
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Primary mesenchyme cell migration requires a chondroitin sulfate/dermatan sulfate proteoglycan.
Developmental Biology, 1991Co-Authors: Mary Constance Lane, Michael SolurshAbstract:Abstract Primary mesenchyme cell migration in the sea urchin embryo is inhibited by sulfate deprivation and exposure to exogenous β- d -Xylosides, two treatments known to disrupt proteoglycan synthesis. We show that in the developing sea urchin, exogenous Xyloside affects the synthesis by the primary mesenchyme cells of a very large, cell surface chondroitin sulfate/dermatan sulfate proteoglycan. This proteoglycan is present in a partially purified fraction that restores migratory ability to defective cells in vitro. The integrity of this chondroitin sulfate/dermatan sulfate proteoglycan appears essential for primary mesenchyme cell migration since treatment of actively migrating cells with chondroitinase ABC reversibly inhibited their migration in vitro.
J. N. Cogburn - One of the best experts on this subject based on the ideXlab platform.
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Sulphation of proteochondroitin and 4-methylumbelliferyl beta-D-Xyloside-chondroitin formed by mouse mastocytoma cells cultured in sulphate-deficient medium.
The Biochemical journal, 1993Co-Authors: Jeremiah E. Silbert, Geetha Sugumaran, J. N. CogburnAbstract:Mouse mastocytoma cells were cultured in medium containing [3H]GlcN and concentrations of [35S]sulphate varying from 0.01 to 0.5 mM. Intracellular [35S]sulphate incorporation increased severalfold from the lowest concentrations, reaching a maximum at 0.1-0.2 mM, whereas incorporation of [3H]hexosamine remained constant at all sulphate concentrations. Proteo[3H]-chondroitin [35S]sulphate was isolated and incubated with chondroitin ABC lyase, yielding 35S-labelled and/or 3H-labelled delta Di-0S and delta Di-4S disaccharide products. The increasing percentage of delta Di-4S was consistent with the increasing sulphate incorporation at each higher [35S]sulphate concentration. Examination of proteochondroitin [35S]sulphate size by Sepharose CL-6B chromatography indicated a range consistent with various numbers of glycosaminoglycan chains on the protease-resistant serglycin core protein. Alkali-cleaved chondroitin [35S]sulphate products indicated similar size distributions at all sulphate concentrations with no indication of preferential sulphation being related to smaller or larger size. DEAE-cellulose chromatography of [3H]chondroitin [35S]sulphate glycosaminoglycans indicated a random undersulphation as [35S]sulphate concentration was lowered. Addition of 4-methylumbelliferyl beta-D-Xyloside to the cultures resulted in a 2-2.5-fold stimulation of [3H]chondroitin [35S]sulphate synthesis with formation of beta-Xyloside-[3H]chondroitin [35S]sulphate which was much smaller, as estimated by Sepharose CL-6B chromatography, than the decreased amount of [3H]chondroitin [35S]sulphate derived from proteo[3H]chondroitin [35S]sulphate. Much higher concentrations of sulphate were necessary to produce sulphation of the beta-Xyloside-[3H]chondroitin comparable with that of proteo[3H]-chondroitin, as indicated by chondroitin ABC lyase products and DEAE-cellulose chromatography. The specific radioactivities of the [3H]GalN in the proteo[3H]chondroitin [35S]sulphate and beta-Xyloside-[3H]chondroitin [35S]sulphate were calculated from the 3H and 35S c.p.m. of isolated dual-labelled delta Di-4S from each, and indicated that the presence of the beta-Xyloside resulted in a dilution of the [3H]GlcN by endogenous GlcN that was 4 times higher than that of cultures lacking the beta-Xyloside. The higher sulphate concentrations needed for sulphation of beta-Xyloside-chondroitin suggests that the membrane-bound nature of the proteochondroitin acceptor in juxtaposition to a chondroitin sulphate-synthesizing enzyme complex effectively reduces the apparent Km for adenosine 3'-phosphate 5'-phosphosulphate.
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Sulphation of proteochondroitin and 4-methylumbelliferyl β-d-Xyloside-chondroitin formed by mouse mastocytoma cells cultured in sulphate-deficient medium
Biochemical Journal, 1993Co-Authors: Jeremiah E. Silbert, Geetha Sugumaran, J. N. CogburnAbstract:Mouse mastocytoma cells were cultured in medium containing [3H]GlcN and concentrations of [35S]sulphate varying from 0.01 to 0.5 mM. Intracellular [35S]sulphate incorporation increased severalfold from the lowest concentrations, reaching a maximum at 0.1-0.2 mM, whereas incorporation of [3H]hexosamine remained constant at all sulphate concentrations. Proteo[3H]-chondroitin [35S]sulphate was isolated and incubated with chondroitin ABC lyase, yielding 35S-labelled and/or 3H-labelled delta Di-0S and delta Di-4S disaccharide products. The increasing percentage of delta Di-4S was consistent with the increasing sulphate incorporation at each higher [35S]sulphate concentration. Examination of proteochondroitin [35S]sulphate size by Sepharose CL-6B chromatography indicated a range consistent with various numbers of glycosaminoglycan chains on the protease-resistant serglycin core protein. Alkali-cleaved chondroitin [35S]sulphate products indicated similar size distributions at all sulphate concentrations with no indication of preferential sulphation being related to smaller or larger size. DEAE-cellulose chromatography of [3H]chondroitin [35S]sulphate glycosaminoglycans indicated a random undersulphation as [35S]sulphate concentration was lowered. Addition of 4-methylumbelliferyl beta-D-Xyloside to the cultures resulted in a 2-2.5-fold stimulation of [3H]chondroitin [35S]sulphate synthesis with formation of beta-Xyloside-[3H]chondroitin [35S]sulphate which was much smaller, as estimated by Sepharose CL-6B chromatography, than the decreased amount of [3H]chondroitin [35S]sulphate derived from proteo[3H]chondroitin [35S]sulphate. Much higher concentrations of sulphate were necessary to produce sulphation of the beta-Xyloside-[3H]chondroitin comparable with that of proteo[3H]-chondroitin, as indicated by chondroitin ABC lyase products and DEAE-cellulose chromatography. The specific radioactivities of the [3H]GalN in the proteo[3H]chondroitin [35S]sulphate and beta-Xyloside-[3H]chondroitin [35S]sulphate were calculated from the 3H and 35S c.p.m. of isolated dual-labelled delta Di-4S from each, and indicated that the presence of the beta-Xyloside resulted in a dilution of the [3H]GlcN by endogenous GlcN that was 4 times higher than that of cultures lacking the beta-Xyloside. The higher sulphate concentrations needed for sulphation of beta-Xyloside-chondroitin suggests that the membrane-bound nature of the proteochondroitin acceptor in juxtaposition to a chondroitin sulphate-synthesizing enzyme complex effectively reduces the apparent Km for adenosine 3′-phosphate 5′-phosphosulphate.
Ulf Ellervik - One of the best experts on this subject based on the ideXlab platform.
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lc ms ms characterization of Xyloside primed glycosaminoglycans with cytotoxic properties reveals structural diversity and novel glycan modifications
Journal of Biological Chemistry, 2018Co-Authors: Andrea Persson, Alejandro Gomez Toledo, Egor Vorontsov, Waqas Nasir, Daniel Willen, Fredrik Noborn, Ulf Ellervik, Katrin Mani, Jonas NilssonAbstract:Structural characterization of glycosaminoglycans remains a challenge but is essential for determining structure-function relationships between glycosaminoglycans and the biomolecules with which they interact and for gaining insight into the biosynthesis of glycosaminoglycans. We have recently reported that Xyloside-primed chondroitin/dermatan sulfate derived from a human breast carcinoma cell line, HCC70, has cytotoxic effects and shown that it differs in disaccharide composition from nontoxic chondroitin/dermatan sulfate derived from a human breast fibroblast cell line, CCD-1095Sk. To further investigate the structural requirements for the cytotoxic effect, we developed a novel LC-MS/MS approach based on reversed-phase dibutylamine ion-pairing chromatography and negative-mode higher-energy collision dissociation and used it in combination with cell growth studies and disaccharide fingerprinting. This strategy enabled detailed structural characterization of linkage regions, internal oligosaccharides, and nonreducing ends, revealing not only differences between Xyloside-primed chondroitin/dermatan sulfate from HCC70 cells and CCD-1095Sk cells, but also sialylation of the linkage region and previously undescribed methylation and sulfation of the nonreducing ends. Although the Xyloside-primed chondroitin/dermatan sulfate from HCC70 cells was less complex in terms of presence and distribution of iduronic acid than that from CCD-1095Sk cells, both glucuronic acid and iduronic acid appeared to be essential for the cytotoxic effect. Our data have moved us one step closer to understanding the structure of the cytotoxic chondroitin/dermatan sulfate from HCC70 cells primed on Xylosides and demonstrate the suitability of the LC-MS/MS approach for structural characterization of glycosaminoglycans.
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Naphthyl Thio- and Carba-xylopyranosides for Exploration of the Active Site of β-1,4-Galactosyltransferase 7 (β4GalT7)
Chemistry - A European Journal, 2017Co-Authors: Karin Thorsheim, Daniel Willen, Emil Tykesson, Jonas Ståhle, Jean-pierre Praly, Sébastien Vidal, Magnus Johnson, Göran Widmalm, Sophie Manner, Ulf EllervikAbstract:Xyloside analogues with substitution of the endocyclic oxygen atom by sulfur or carbon were investigated as substrates for β-1,4-galactosyltransferase 7 (β4GalT7), a key enzyme in the biosynthesis of glycosaminoglycan chains. The analogues with an endocyclic sulfur atom proved to be excellent substrates for β4GalT7, and were galactosylated approximately fifteen times more efficiently than the corresponding Xyloside. The 5a-carba-β-xylopyranoside in the d-configuration proved to be a good substrate for β4GalT7, whereas the enantiomer in the l-configuration showed no activity. Further investigations by X-ray crystallography, NMR spectroscopy, and molecular modeling provided a rationale for the pronounced activity of the sulfur analogues. Favorable π-π interactions between the 2-naphthyl moiety and a tyrosine side chain of the enzyme were observed for the thio analogues, which open up for the design of efficient GAG primers and inhibitors.
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hydroxylated oxanes as Xyloside analogs for determination of the minimal binding requirements of β4galt7
Tetrahedron Letters, 2017Co-Authors: Karin Thorsheim, Sebastian Clementson, Emil Tykesson, Dennis Bengtsson, Daniel Strand, Ulf EllervikAbstract:β-1,4-Galactosyltransferase 7 (β4GalT7) is a key enzyme in the biosynthesis of glycosaminoglycan (GAG) chains. Natural and synthetic Xylosides can be used to both inhibit and prime GAG synthesis by acting as inhibitors or substrates for β4GalT7. In this report, we exploit hydroxylated oxanes as deoxygenated Xyloside analogs to clarify the minimum protein-ligand interactions required for galactosylation and/or inhibition. Enantiomerically pure substances were synthesized using a chiral pool approach whereas the corresponding racemates were obtained from simple starting materials. The results of a β4GalT7 assay show that a single hydroxyl group on an oxane ring is insufficient to induce galactosylation or inhibition, which implies that at least two substituents, one of which being 3-OH, needs to be present.
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Xyloside primed chondroitin sulfate dermatan sulfate from breast carcinoma cells with a defined disaccharide composition has cytotoxic effects in vitro
Journal of Biological Chemistry, 2016Co-Authors: Andrea Persso, Ulf Ellervik, Anders Malmstrom, Emil Tykesso, Gunilla Westergrenthorsso, Katri ManiAbstract:We have previously reported that the Xyloside 2-(6-hydroxynaphthyl) β-D-xylopyranoside (XylNapOH), in contrast to 2-naphthyl β-D-xylopyranoside (XylNap), specifically reduces tumor growth both in vitro and in vivo. Although there are indications that this could be mediated by the Xyloside-primed glycosaminoglycans (GAGs) and that these differ in composition depending on Xyloside and cell type, detailed knowledge regarding a structure-function relationship is lacking. In this study, we isolated XylNapOH- and XylNap-primed GAGs from a breast carcinoma cell line, HCC70, and a breast fibroblast cell line, CCD-1095Sk, and demonstrated that both XylNapOH- and XylNap-primed chondroitin sulfate/dermatan sulfate (CS/DS) GAGs derived from HCC70 cells had a cytotoxic effect on HCC70 cells and CCD-1095Sk cells. The cytotoxic effect appeared to be mediated by induction of apoptosis and was inhibited in a concentration-dependent manner by the XylNap-primed heparan sulfate (HS) GAGs. In contrast, neither the CS/DS nor the HS derived from CCD-1095Sk cells primed on XylNapOH or XylNap had any effect on the growth of HCC70 cells or CCD-105Sk cells. These observations were related to the disaccharide composition of the XylNapOH- and XylNap-primed GAGs, which differed considerably between the two cell lines, but was similar when the GAGs were derived from the same cell line. To our knowledge, this is the first report on cytotoxic effects mediated by CS/DS. (Less)
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Synthesis of aromatic C-Xylosides by position inversion of glucose
Bioorganic & medicinal chemistry, 2006Co-Authors: Jesper Malmberg, Katrin Mani, Elin Säwén, Anders Wirén, Ulf EllervikAbstract:Two formally C-xylosylated analogs to 2-naphthyl beta-D-xylopyranoside, which is known to initiate priming of glucosaminoglycan chains, were synthesized by a position inversion of glucose (i.e., position I becomes position 5). The D-C-Xyloside showed priming, while the L-C-Xyloside did not initiate priming. (c) 2006 Elsevier Ltd. All rights reserved.
Mary Constance Lane - One of the best experts on this subject based on the ideXlab platform.
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primary mesenchyme cell migration requires a chondroitin sulfate dermatan sulfate proteoglycan
Developmental Biology, 1991Co-Authors: Mary Constance Lane, Michael SolurshAbstract:Abstract Primary mesenchyme cell migration in the sea urchin embryo is inhibited by sulfate deprivation and exposure to exogenous β- d -Xylosides, two treatments known to disrupt proteoglycan synthesis. We show that in the developing sea urchin, exogenous Xyloside affects the synthesis by the primary mesenchyme cells of a very large, cell surface chondroitin sulfate/dermatan sulfate proteoglycan. This proteoglycan is present in a partially purified fraction that restores migratory ability to defective cells in vitro. The integrity of this chondroitin sulfate/dermatan sulfate proteoglycan appears essential for primary mesenchyme cell migration since treatment of actively migrating cells with chondroitinase ABC reversibly inhibited their migration in vitro.
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Primary mesenchyme cell migration requires a chondroitin sulfate/dermatan sulfate proteoglycan.
Developmental Biology, 1991Co-Authors: Mary Constance Lane, Michael SolurshAbstract:Abstract Primary mesenchyme cell migration in the sea urchin embryo is inhibited by sulfate deprivation and exposure to exogenous β- d -Xylosides, two treatments known to disrupt proteoglycan synthesis. We show that in the developing sea urchin, exogenous Xyloside affects the synthesis by the primary mesenchyme cells of a very large, cell surface chondroitin sulfate/dermatan sulfate proteoglycan. This proteoglycan is present in a partially purified fraction that restores migratory ability to defective cells in vitro. The integrity of this chondroitin sulfate/dermatan sulfate proteoglycan appears essential for primary mesenchyme cell migration since treatment of actively migrating cells with chondroitinase ABC reversibly inhibited their migration in vitro.
Balagurunathan Kuberan - One of the best experts on this subject based on the ideXlab platform.
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Structural analysis of Xyloside primed GAG chains.
2017Co-Authors: Jie Shi Chua, Vy M. Tran, Mausam Kalita, Maritza V. Quintero, Orlando Antelope, Geethu Muruganandam, Yukio Saijoh, Balagurunathan KuberanAbstract:HUVEC cultures were treated with Xylosides 3 or 4 at 1, 10 or 100 μM with [S35]-SO4 and incubated for 2 days. GAGs from the media and cell extracts were then purified over a DEAE column. BLUE: Endogenous GAGs, GREEN: Xyloside 3 primed GAGs, and RED: Xyloside 4 primed GAGs. (A) 100,000 CPM of purified radiolabeled GAGs when primed at 1 or 10 μM, and 200,000 CPM of GAGs when primed at 100 μM were analyzed separately over a DEAE-3SW column for anion-exchange chromatography. When primed at 10 and 100 μM, Xyloside 3 primed GAGs have similar HS/CS ratios to the endogenous GAGs while Xyloside 4 primed GAGs have approximately 3–4 times the amount of CS than HS. When primed at 1 μM, both 3 and 4 primed more CS than HS, although 4 still primes relatively more CS than 3 (B). Radiolabeled GAGs were digested with heparitinase I/II/III and analyzed over the CarboPac analytical PA1 column. Generally, Xyloside primed GAGs have similar HS compositions to endogenous GAGs with the exception of Xyloside 4 primed at 100 μM that has an extra disulfated peak. (C) Radiolabeled GAGs were digested with chondroitinase ABC and analyzed over YMC PA-G column. The CS disaccharides primed by the Xylosides have additional disulfated peaks compared to endogenous CS; All peaks were identified by matching with HS and CS disaccharide standards.
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A glycan-based approach to therapeutic angiogenesis
2017Co-Authors: Jie Shi Chua, Vy M. Tran, Mausam Kalita, Maritza V. Quintero, Orlando Antelope, Geethu Muruganandam, Yukio Saijoh, Balagurunathan KuberanAbstract:Angiogenesis, the sprouting of new blood vessels from existing vasculature, involves multiple complex biological processes, and it is an essential step for hemostasis, tissue healing and regeneration. Angiogenesis stimulants can ameliorate human disease conditions including limb ischemia, chronic wounds, heart disease, and stroke. The current strategies to improve the bioavailability of pro-angiogenic growth factors, including VEGF and FGF2, have remained largely unsuccessful. This study demonstrates that small molecules, termed click-Xylosides, can promote angiogenesis in the in vitro matrigel tube formation assay and the ex ovo chick chorioallantoic membrane assay, depending on their aglycone moieties. Xyloside treatment enhances network connectivity and cell survivability, thereby, maintaining the network structures on matrigel culture for an extended period of time. These effects were achieved via the secreted Xyloside-primed glycosaminoglycans (GAG) chains that in part, act through an ERK1/2 mediated signaling pathway. Through the remodeling of GAGs in the extracellular matrix of endothelial cells, the glycan approach, involving Xylosides, offers great potential to effectively promote therapeutic angiogenesis.
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The effect of click-Xylosides on cell proliferation, viability, cell migration and cell morpholgy differentially in a concentration dependent manner.
2017Co-Authors: Jie Shi Chua, Vy M. Tran, Mausam Kalita, Maritza V. Quintero, Orlando Antelope, Geethu Muruganandam, Yukio Saijoh, Balagurunathan KuberanAbstract:(A) Cells were treated with Xylosides 2, 3 and 4 at 1, 10 and 100 μM over a period of 4 days and the number of cells were counted each day. Data shown was averaged over three experiments. Although a small increase in cell number was observed after Day 2 for all Xylosides treated at 1 μM, no statistical significance were found with the One-way ANOVA. (B) The cells were labeled with Calcein AM just before treatment with Xylosides 2, 3 and 4 at 1, 10 and 100 μM and after 72 hours of treatment, and the increase in fluorescence were used for comparison. Xyloside treatment did not affect cell viability. Data shown was averaged over six experiments. No statistical significance were found with the One-way ANOVA (S2A Table). (C) The effect of the Xylosides on cell migration was determined with the t-scratch assay. Cells were grown to confluence and two scratches were made in each well, forming a cross (t) in the middle. The cells were then treated with the corresponding Xylosides. Images of the cross were taken at the 12th and the 30th hour after the scratches were made. Cell area and circularity were obtained from the images of the t-scratch assay at the 12th hour. At least 50 cells were randomly chosen from each image and manually outlined in ImageJ to obtain area and circularity values. Circularity values ranged from 0 (infinitely elongated polygon) to 1 (perfect circle). Data shown was averaged over five experiments. No statistical significance were found with One-way ANOVA (S2A Table). Two-sample T-tests (unpaired data with unequal variances) were performed for each Xyloside treatment against the untreated control (S2B and S2C Table). Statistical significance, as determined by the student T-test against the no treatment control, is indicated by * when p
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Xylosides and Xylosides primed GAGs increases network connectivity of the HUVEC networks on matrigel.
2017Co-Authors: Jie Shi Chua, Vy M. Tran, Mausam Kalita, Maritza V. Quintero, Orlando Antelope, Geethu Muruganandam, Yukio Saijoh, Balagurunathan KuberanAbstract:(A) Priming activity of the Xylosides in HUVECs determined by radiolabeling with [S35]-SO4 (n = 3) depicted as fold change relative to control (= 1); The network properties of matrigel tube formation assay when cultured in (B) fresh media with Xylosides at 100 μM concentration (n = 9), (C) 1 and 10 μM concentration (n = 4 for both concentrations) and (D) conditioned media with unprimed Xylosides and Xyloside-primed GAGs (n = 3), were quantified after 8 hours with the Angiogenesis Analyzer plugin. Conditioned media was collected from HUVECs treated with 100 μM of Xylosides (or no treatment for control samples) for 2 days before use in the matrigel tube formation assay. The network properties compared are the number of junctions that are the branching points, segments that are the tube like elements delimited by 2 junctions, meshes thatare enclosed by segments and the total branching length of the formed network. One-way ANOVA with post-hoc Tukey’s test was used to determine statistical significance (S3B, S3C, S3D and S3F Table). The network characteristics are depicted as fold change relative to the untreated control in (E). One sample T-test against the mean value of 1 (control) was used to determine statistical significance (S3E and S3G Table). Generally, the greatest fold change was seen when the conditioned media was used, indicating that the differences between the treated samples and the untreated control was more pronounced with the conditioned media. The number of experiments conducted is indicated by the stated n value with 3 technical replicates per experiment. Statistically significant difference is indicated by * when p
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Click-Xylosides promoted endothelial tube formation in the matrigel tube formation assay.
2017Co-Authors: Jie Shi Chua, Vy M. Tran, Mausam Kalita, Maritza V. Quintero, Orlando Antelope, Geethu Muruganandam, Yukio Saijoh, Balagurunathan KuberanAbstract:(A) Nine click-Xylosides were preliminary screened for their ability to facilitate HUVEC network formation in matrigel cultures. The respective images were taken at 8 hours after cell seeding. (B) The network properties of the preliminary screening experiment was quantified at 8 hours using the Angiogenesis Analyser ImageJ plugin. The network properties compared are the number of junctions which are branching points, segments which are the tube like elements delimited by two junctions, meshes which are enclosed by segments and the total branching length of the formed network. The data for this preliminary study was averaged over three experiments. No statistical significance were observed between the treatments as determined by one-way ANOVA (S1A Table). Two-sample T-tests (unpaired data with unequal variances) were performed for each Xyloside treatment against the untreated control. Statistical significance, as determined by the student T-test against the no treatment control, is indicated by * when p
