• Framing stress and associated behaviours at work: an ethnography study in the United Kingdom

      Hampton, Paul; Chinyio, Ezekiel; Riva, Silvia (Emerald Publishing Group, 2019-11-18)
      Aim: The purpose is to understand more precisely the culture and interpersonal behaviours associated with stress. Methods: The research was conducted using a qualitative approach through an ethnographic methodology in relation to three companies. The greater part of the data collection period was structured into observations that ranged between 2 and 4 hours per day, 1 to 3 days per week, for a period of 6 months. A total of 10 sites were explored; and on each site, the observations involved activities by 5 to 20 people. Findings: The results showed the pivotal importance of interpersonal relationships in coping with the uncertainty of working conditions, the coordination of team-work, and managing responsibilities and power interactions. It was found that the impact of stress is multifaceted, affecting the physical status, interpersonal relationships, work performance, and emotional wellbeing of construction workers. The workers who were studied emphasised five sources of support that help moderate work-related stress: additional tools such as communication systems and software, a facilitated access to professional help (e.g. psychological services), organisational changes in leadership, provision of resources for the wellbeing of personnel (e.g. job training) and better teamwork. Practical implications: The study underlines the importance of dedicated services for stress management and specific training-related abilities devoted to reinforcing positive person-organization dynamics. In particular, the abilities should relate to managing the impact of stress in terms of physique, interpersonal relationships, work performance, and emotional well-being. Originality/value: This is one of the first studies to adopt a psychological perspective for understanding construction scenarios and phenomena and was conducted by a qualified psychologist.
    • Fungal gene sequences make excellent models for teaching data mining

      Hooley, Paul; Burns, Alan T. H.; Whitehead, Michael P. (Elsevier Science Direct, 2004)
      A brief introductory exercise in the use of on-line databases to examine fungal genes and their products is described. Fungal genes make particularly good teaching models owing to their relatively simple eukaryotic structure and wide range of homologues in higher organisms including humans. An evaluation of students' reactions to the exercise is included.
    • Fungal osmotolerance.

      Hooley, Paul; Fincham, Daron A.; Whitehead, Michael P.; Clipson, Nicholas J. W. (Elsevier Science Direct, 2003)
      Abstract not available. Article Outline as follows: I. Introduction. II. Physiological Mechanisms of Osmotolerance. III. Control of Osmotic Responses at the Molecular Level. A. Osmotic Adjustment in Yeasts: 1. Saccharomyces cerevisiae. a. Regulation of osmotic responses at the molecular level. b. Transcriptional responses. 2. Debaryomyces hansenii. 3. Other Yeasts. B. Oscp>smotic Adjustment in Filamentous Fungal Species: 1. Genes with “Osmotic” Phenotypes. 2. Molecular Approaches. 3. A. nidulans as a Model Expression System. 4. Life Cycle Stage Sensitivity. 5. Regulation of Osmotic Responses in A. nidulans. a. Introduction to transcription factors. IV. Conclusions. A. Comparisons of Yeast and Filamentous Models. B. Sporulation and Development. C. Origins of Fungal Stress Response Genes. D. Specificity of Stress Responses. E. Concluding Remarks. Acknowledgements. References.
    • Gain of 1q and loss of 22 are the most common changes detected by comparative genomic hybridisation in paediatric ependymoma.

      Ward, Samantha; Harding, Brian; Wilkins, Peter; Harkness, William; Hayward, Richard; Darling, John L.; Thomas, David G.; Warr, Tracy (Wiley Interscience, 2001)
      Ependymomas are the third most common brain tumour in the paediatric population. Although cytogenetic and molecular analyses have pinpointed deletions of chromosomes 6q, 17, and 22 in a subset of tumours, definitive patterns of genetic aberrations have not been determined. In the present study, we analysed 40 ependymomas from paediatric patients for genomic loss or gain using comparative genomic hybridisation (CGH). Eighteen of the tumours (45%) had no detectable regions of imbalance. In the remaining cases, the most common copy number aberrations were loss of 22 (25% of tumours) and gain of 1q (20%). Three regions of high copy number amplification were noted at 1q24-31 (three cases), 8q21-23 (two cases), and 9p (one case). Although there was no association with the loss or gain of any chromosome arm or with benign versus anaplastic histologic characteristics, the incidence of gain of 7q and 9p and loss of 17 and 22 was significantly higher in recurrent versus primary tumours. This study has identified a number of chromosomal regions that may contain candidate genes involved in the development of different subgroups of ependymoma.
    • Gene encoding the collagen type I and thrombospondin receptor CD36 is located on chromosome 7q11.2.

      Fernández-Ruiz, Elena; Armesilla, Angel Luis; Sánchez-Madrid, Francisco; Vega, Miguel A. (Elsevier BV, 1993)
      The human CD36 is a member of a gene family of structurally related glycoproteins and functions as a receptor for collagen type I and thrombospondin. CD36 also binds to red blood cells infected with the human malaria parasite Plasmodium falciparum. In the present study, the CD36 gene was assigned to chromosome 7 by using the polymerase chain reaction with DNA from human-hamster somatic cell hybrids. Furthermore, the use of a CD36 genomic probe has allowed the localization of the CD36 locus to the 7q11.2 band by fluorescence in situ hybridization coupled with GTG-banding.
    • Generating monoclonal antibody probes and techniques for characterizing and localizing reactivity to antigenic determinants

      Nelson, Paul N. (Oxford: Oxford University Press, 2001)
      This book: Epitope Mapping covers all the major methods for the identification and definition of epitopes. The Pepscan assay is used to define B cell epitopes and makes use of synthetic peptides but can only be used if the amino acid sequence is known. It can be adapted for the delineation of both helper T cells and cytotoxic T cells. The identification of combined B and T cell epitopes can also be achieved using synthetic peptides. There are other methodologies for analysing for cytotxic T cell epitopes such as the purification of antigens presented by MHC class I molecules and expression cloning. Site directed mutagenesis is also a powerful tool in epitope mapping and can be used to evaluate the role of single amino acids in immune complex formation. Protein footprinting makes use of monoclonal antibodies produced by hybridoma technology and relies on the fact that the epitope is protected from cleavage when bound as an antibody-antigen complex. It is only useful for small antigens. Other monoclonal antibody assays such as enzyme linked immunosorbent assay and haemaglutination and slot-blotting may also be used in epitope mapping. Random phage display libraries bring together the genetic and amino acid peptide sequence and can be screened with antibody and the resulting peptide DNA sequenced to confirm the amino acid sequence of a specific eptiope. Investigation of carbohydrates can also be useful to eptitope mapping as deglycosylation can lead to loss of antigenic activity. Epitopes are important to the pharmaceutical industry and wherever appropriate, pharmaceutical applications of the methods described are included. For each method there is a description of the technology, protocols, trouble-shooting, and advice on when to use the method. This book will therefore be invaluable to any researcher involved in epitope mapping.
    • Generation and characterization of monoclonal antibodies to the neural crest.

      Shakil, T.; Richardson, M. K.; Waldron, E.E.; Conde, Gillian; Wood, S.; Bland, Y.; Reynolds, Gary; Murray, Paul G.; Nelson, Paul N. (New Rochelle (NY): Mary Ann Liebert, Inc., 2001)
      The generation of monoclonal antibodies (MAbs) specific for quail neural crest may provide valuable tools for studying the differentiation of embryonic precursor cells. Unfortunately, relatively few antibodies are available because of the difficulty in obtaining sufficient cells for in vivo immunization strategies. We have overcome this problem by using intrasplenic immunization with formaldehyde-fixed cells harvested from neural crest cultures. In addition, booster injections of cultured whole-embryo cells were administered intraperitoneally. Following two fusions, a total of 18 hybridomas were generated with antibody reactivity to the cytoplasm of neural crest cells. Furthermore, 32 were reactive against both somite (a noncrest mesodermal control) and crest cultures, whilst 15 were not reactive. Out of those hybridomas reactive with neural crest, six designated 160D, 164D, OE, 12E, 120E and 124E were further characterized. Interestingly MAb supernatants OE, 12E, 120E, and 124E exhibited reactivity against some but not all neural crest cells suggesting that they might recognise subpopulations. Immunoglobulin isotyping of supernatants revealed that 4 (160D, 164D, OE, and 120E) were IgM and 2 (12E and 124E) were IgG(2b). On assessing their reactivity against human tissue sections, all six hybridoma supernatants cross-reacted with neuroendocrine cells within appendix, colon and rectum. These MAbs could provide novel reagents for the understanding of neural crest development.
    • Genomic and transcriptomic characterisation of undifferentiated pleomorphic sarcoma of bone

      Ali, Naser M.; Niada, Stefania; Brini, Anna T.; Morris, Mark R.; Kurusamy, Sathishkumar; Alholle, Abdullah; Huen, David; Antonescu, Cristina R.; Tirode, Franck; Sumathi, Vaiyapuri; et al. (Wiley, 2018-12-27)
      Undifferentiated pleomorphic sarcoma of bone (UPSb), is a rare primary bone sarcoma that lacks a specific line of differentiation. There is very little information about the genetic alterations leading to tumourigenesis or malignant transformation. Distinguishing between UPSb and other malignant bone sarcomas, including dedifferentiated chondrosarcoma and osteosarcoma, can be challenging due to overlapping features. To explore the genomic and transcriptomic landscape of UPSb tumours, whole-exome sequencing (WES) and RNA Sequencing (RNA-Seq) were performed on UPSb tumours. All tumours lacked hotspot mutations in IDH1/2 132 or 172 codons, thereby excluding the diagnosis of dedifferentiated chondrosarcoma. Recurrent somatic mutations in TP53 were identified in 4/14 samples (29%). Moreover, recurrent mutations in histone chromatin remodelling genes, including H3F3A, ATRX and DOT1L, were identified in 5/14 samples (36%), highlighting the potential role of deregulated chromatin remodelling pathways in UPSb tumourigenesis. The majority of recurrent mutations in chromatin remodelling genes identified here are reported in COSMIC, including the H3F3A G35 and K36 hotspot residues. Copy number alteration analysis identified gains and losses in genes that have been previously altered in UPSb or UPS of soft tissue. Eight somatic gene fusions were identified by RNA-Seq, two of which, CLTC-VMP1 and FARP1-STK24, were reported previously in multiple cancers. Five gene fusions were genomically characterised. Hierarchical clustering analysis, using RNA-Seq data, distinctly clustered UPSb tumours from osteosarcoma and other sarcomas, thus molecularly distinguishing UPSb from other sarcomas. RNA-Seq expression profiling analysis and quantitative RT-PCR showed an elevated expression in FGF23 which can be a potential molecular biomarker in UPSb. To our knowledge, this study represents the first comprehensive WES and RNA-Seq analysis of UPSb tumours revealing novel protein-coding recurrent gene mutations, gene fusions and identifying a potential UPSb molecular biomarker, thereby broadening the understanding of the pathogenic mechanisms and highlighting the possibility of developing novel targeted therapeutics.
    • Germline Mutations in the CDKN2B Tumor Suppressor Gene Predispose to Renal Cell Carcinoma.

      Jafri, Mariam; Wake, Naomi C; Ascher, David B; Pires, Douglas E V; Gentle, Dean; Morris, Mark R.; Rattenberry, Eleanor; Simpson, Michael A; Trembath, Richard C; Weber, Astrid; et al. (American Association for Cancer Research, 2015-04-14)
      Familial renal cell carcinoma (RCC) is genetically heterogeneous and may be caused by mutations in multiple genes, including VHL, MET, SDHB, FH, FLCN, PTEN, and BAP1. However, most individuals with inherited RCC do not have a detectable germline mutation. To identify novel inherited RCC genes, we undertook exome resequencing studies in a familial RCC kindred and identified a CDKN2B nonsense mutation that segregated with familial RCC status. Targeted resequencing of CDKN2B in individuals (n = 82) with features of inherited RCC then revealed three candidate CDKN2B missense mutations (p.Pro40Thr, p.Ala23Glu, and p.Asp86Asn). In silico analysis of the three-dimensional structures indicated that each missense substitution was likely pathogenic through reduced stability of the mutant or reduced affinity for cyclin-dependent kinases 4 and 6, and in vitro studies demonstrated that each of the mutations impaired CDKN2B-induced suppression of proliferation in an RCC cell line. These findings identify germline CDKN2B mutations as a novel cause of familial RCC.
    • Glucose induces and leptin decreases expression of uncoupling protein-2 mRNA in human islets.

      Brown, James E. P.; Thomas, Steven; Digby, Janet E.; Dunmore, Simon J. (Elsevier BV, 2002)
      Elevated islet uncoupling protein-2 (UCP-2) impairs beta-cell function and UCP-2 may be increased in clinical obesity and diabetes. We investigated the effects of glucose and leptin on UCP-2 expression in isolated human islets. Human islets were incubated for 24 h with glucose (5.5-22 mmol/l)+/-leptin (0-10 nmol/l). Some islet batches were incubated at high (22 mmol/l), and subsequently lower (5.5 mmol/l), glucose to assess reversibility of effects. Leptin effects on insulin release were also measured. Glucose dose-dependently increased UCP-2 expression in all islet batches, maximally by three-fold. This was not fully reversed by subsequently reduced glucose levels. Leptin decreased UCP-2 expression by up to 75%, and maximally inhibited insulin release by 47%, at 22 mmol/l glucose. This is the first report of UCP-2 expression in human islets and provides novel evidence of its role in the loss of beta-cell function in diabetes.
    • Granulocyte-macrophage colony-stimulating factor, phorbol ester, and sodium butyrate induce the CD11c integrin gene promoter activity during myeloid cell differentiation.

      Rubio, M.A.; Lopez-Rodriguez, C.; Nueda, A.; Aller, P.; Armesilla, Angel Luis; Vega, Miguel A.; Corbí, A.L. (American Society of Hematology, 1995)
      To analyze the activity of the CD11c promoter during myeloid differentiation without the limitations of transient expression systems, we have stably transfected the myeloid U937 cell line with the pCD11C361-Luc plasmid, in which the expression of the firefly luciferase cDNA is driven by the CD11c promoter region -361/+43, previously shown to confer myeloid specificity to reporter genes. The stable transfectants (U937-C361) retained the ability to differentiate in response to phorbol-ester (PMA), sodium butyrate (SB), granulocyte-macrophage colony-stimulating factor (GM-CSF), and other differentiating agents. U937-C361 differentiation correlated with increased cellular luciferase levels, showing the inducibility of the CD11c promoter during myeloid differentiation and establishing the U937-C361 cells as a suitable system for studying the myeloid differentiation-inducing capacity of cytokines, growth, factors, and other biological response modifiers. Unexpectedly, the inducibility of the CD11c gene promoter showed distinct kinetics and magnitude on the PMA-, SB-, GM-CSF-triggered differentiation. Moreover, SB synergized with either PMA or GM-CSF in enhancing both the CD11c promoter activity and the cell surface expression of p150,95 on differentiating U937 cells. Furthermore, we showed the existence of a c-Myb-binding site at -85, the importance of the -99/-61 region in the CD11c promoter inducibility during PMA- or SB-triggered differentiation, and the dependency of the GM-CSF and PMA responsiveness of the CD11c promoter on an intact AP-1-binding site located at -60. These results, together with the lack of functional effect of mutations disrupting the Sp1-and Myb-binding sites within the proximal region of the CD11c promoter, indicate that the myeloid differentiation pathways indicated by SB and phorbol esters (or GM-CSF) activate a distinct set of transcription factors and show that the myeloid differentiation-inducibility of the CD11c gene maps to the -99/-53 proximal region of the promoter.
    • Group III metabotropic glutamate receptor activation inhibits Ca2+ influx and nitric oxide synthase activity in bone marrow stromal cells.

      Foreman, Megan A.; Gu, Yuchun; Howl, John D.; Jones, Sarah; Publicover, Stephen J. (Wiley InterScience, 2005)
      Nitric oxide (NO) is pivotal to bone physiology. In the central nervous system constitutive, Ca(2+)-calmodulin regulated NO synthase activity and glutamate signalling are intimately linked. Since L-glutamate signalling occurs in bone and is implicated in bone regulation, we have investigated the effect of L-glutamate on NO synthase in bone-derived cells. Treatment of marrow stromal cells with L-glutamate reduced basal NO synthase activity by 40%. Imaging showed that L-glutamate caused a rapid, usually localised and slowly-reversible fall in [Ca(2+)](i). This effect was resistant to disruption of intracellular Ca(2+) stores but sensitive to extracellular La(3+) or omission of extracellular Ca(2+), demonstrating that glutamate acts by inhibition of membrane Ca(2+) influx. The only previous description of such an effect of L-glutamate is via activation of the group III receptor, mGluR6, in the retina. Using Western blotting and RT-PCR we detected mGluR6 protein and transcripts in marrow stromal cells. The effects of L-glutamate on NOS activity and [Ca(2+)](i) in marrow stromal cells were abolished by a group III mGluR inhibitor, (S)-2-amino-2-methyl-4-phosphonobutyric acid. Recording of membrane potential showed that, similarly to the effects of retinal mGluR6 activation, L-glutamate induced membrane hyperpolarisation (-16 +/- 2 mV), which was also sensitive to group III mGluR inhibition. L-glutamate had no effect on cAMP levels. We conclude that activation of a group III mGluR in bone marrow stromal cells inhibits a Ca(2+)-permeable plasma membrane channel, reducing [Ca(2+)](i) and suppressing generation of NO. These observations directly link bone L-glutamate signalling to processes central to bone growth and regulation.
    • Hepatic drug targeting: phase I evaluation of polymer-bound doxorubicin.

      Seymour, Leonard W.; Ferry, David R.; Anderson, David; Hesslewood, Stuart; Julyan, Peter J.; Poyner, Richard; Doran, Jayne; Young, Annie M.; Burtles, Sally; Kerr, David J. (American Society of Clinical Oncology, 2002)
      PURPOSE: Preclinical studies have shown good anticancer activity following targeting of a polymer bearing doxorubicin with galactosamine (PK2) to the liver. The present phase I study was devised to determine the toxicity, pharmacokinetic profile, and targeting capability of PK2. PATIENTS AND METHODS: Doxorubicin was linked via a lysosomally degradable tetrapeptide sequence to N-(2-hydroxypropyl)methacrylamide copolymers bearing galactosamine. Targeting, toxicity, and efficacy were evaluated in 31 patients with primary (n = 25) or metastatic (n = 6) liver cancer. Body distribution of the radiolabelled polymer conjugate was assessed using gamma-camera imaging and single-photon emission computed tomography. RESULTS: The polymer was administered by intravenous (i.v.) infusion over 1 hour, repeated every 3 weeks. Dose escalation proceeded from 20 to 160 mg/m(2) (doxorubicin equivalents), the maximum-tolerated dose, which was associated with severe fatigue, grade 4 neutropenia, and grade 3 mucositis. Twenty-four hours after administration, 16.9% +/- 3.9% of the administered dose of doxorubicin targeted to the liver and 3.3% +/- 5.6% of dose was delivered to tumor. Doxorubicin-polymer conjugate without galactosamine showed no targeting. Three hepatoma patients showed partial responses, with one in continuing partial remission 47 months after therapy. CONCLUSION: The recommended PK2 dose is 120 mg/m(2), administered every 3 weeks by IV infusion. Liver-specific doxorubicin delivery is achievable using galactosamine-modified polymers, and targeting is also seen in primary hepatocellular tumors.
    • High Performance liquid chromatography-mass spectrometry analysis for rat metabolism and pharmacokinetic studies of lithospermic acid B from danshen

      Cui, Liang; Chan, Wan; Wu, Jian-Lin; Jiang, Zhi-Hong; Chan, Kelvin C.; Cai, Zongwei (Amsterdam: Elsevier, 2008)
      Metabolism and pharmacokinetic studies on rat were conducted for lithospermic acid B, one of the components from Radix Salviae Miltiorrhizae (danshen) that shows many bioactivities. Liquid chromatography–electrospray ionization mass spectrometry method was applied for the determination of lithospermic acid B and its metabolites in samples from in vitro and in vivo metabolism studies. Rat plasma samples collected after intravenous administration were analyzed for obtaining pharmacokinetic data of lithospermic acid B. Four O-methylated metabolites, namely one monomethyl-, two dimethyl- and one trimethyl-lithospermic acid B, were detected when lithospermic acid B was incubated in rat hepatic cytosol. These four metabolites were also detected in rat bile, plasma and feces samples after intravenous administration of lithospermic acid B. The in vitro and in vivo results indicate that the methylation is the main metabolic pathway of lithospermic acid B. The danshen component and its methylated metabolites were excreted to rat bile and feces. (Elsevier)
    • Human endogenous retrovirus HERV-K10 implicated in rheumatoid arthritis and systemic lupus erythematosus: potential pathological triggers?

      Nelson, Paul N.; Shaw, M.; Roden, Denise A.; Freimanis, Graham L.; Nevill, Alan M.; Rylance, Paul (Czech Republic: Palacky University, Olomouc: Faculty of Medicine and Dentistry, 2006)
      Human endogenous retroviruses (HERVs) are a group of integrated RNA viruses within our human genome. Whilst many are regarded as defective, a number possess the potential to generate retroviral products. Indeed HERVs such as those belonging to the HERV-K family produce retroviral particles in the teratocarcinoma cell line GH and the breast cancer cell line T47D. It has been argued that some retroelements may be beneficial to the human host, perhaps conferring a selective advantage, whereas others may be harmful. Furthermore certain HERVs might be involved in the pathogenesis of autoimmune diseases. The precise mechanisms in diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) may include molecular mimicry and superantigen motifs that evoke and augment unwarranted immune responses. The precise mechanisms in diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) may include molecular mimicry and superantigen motifs that evoke and augment unwarranted immune responses. In the RA joint, tissue destruction is evident over time with recruitment of lymphoid and other cells plus the presence of rheumatoid factor that exhibits increased affinity and change in isotype; evidence of an antigen-driven immune response. The precise trigger of course, remains unknown although certain HERVs have been implicated. In a previous study we found evidence for increased expression of HERV-K10 mRNA in patients with RA. Here we have extended this work by investigating the serological expression to HERV-K10 in patients with RA, SLE, osteoarthritis, normals and other inflammatory disease groups. The study utilised a novel peptide ELISA immunoassay using segments of HERV-K10 identified through bioinformatic analysis. In particular, biotinylation of peptides was necessary for serological discrimination between patients. Overall a significant difference (p<0.05) was found for RA patients in terms of antibody activity to HERV-K10. There was also an increased level of antibodies to HERV-K10 in patients with renal lupus although this was below the level of significance. It is possible that HERV-K10 could act as a trigger in RA/SLE through regions of similarity to host proteins. In this case, the immune response to HERV-K10 could lead to collateral damage and pathogenesis of disease.
    • Human endogenous retroviruses: transposable elements with potential?

      Nelson, Paul N.; Hooley, Paul; Roden, Denise A.; Ejtehadi, H. Davari; Rylance, Paul; Warren, Phil; Martin, Jan H.; Murray, Paul G. (Wiley InterScience, 2004)
      Human endogenous retroviruses (HERVs) are a significant component of a wider family of retroelements that constitute part of the human genome. These viruses, perhaps representative of previous exogenous retroviral infection, have been integrated and passed through successive generations within the germ line. The retention of HERVs and isolated elements, such as long-terminal repeats, could have the potential to harm. In this review we describe HERVs within the context of the family of known transposable elements and survey these viruses in terms of superantigens and molecular mimics. It is entirely possible that these mechanisms provide the potential for undesired immune responses.
    • ICAM-1 expression and leukocyte behavior in the microcirculation of chronically ischemic rat skeletal muscles.

      Anderson, Stephen I.; Shiner, Ruth; Brown, Margaret D.; Hudlicka, Olga (Elsevier, 2006)
      In muscle microcirculation, short periods of ischemia followed by reperfusion are known to upregulate leukocyte and endothelial adhesion molecules, but little is known about leukocyte adherence and ICAM-1 expression during chronic ischemia or any likely effect of muscle activity which is recommended in chronic ischemia due to peripheral arterial disease. Leukocyte rolling and stationary adhesion were observed in post-capillary venules in ischemic and contralateral rat extensor digitorum longus (EDL) muscles 3 and 7 days after unilateral ligation of the common iliac artery and in 3-day ischemic EDLs that were electrically stimulated on days 1 and 2 post-ligation (7 x 15 min per day). ICAM-1 was localized immunohistochemically to venular vessels in all muscles. Following ligation, use of the ischemic leg was observed to be restricted for the first 3 days, returning to normal by 7 days. After 3 days, leukocyte rolling/adherence and ICAM-1 expression were no different in ischemic than control muscles, but all were increased in contralateral muscles. In ischemic muscles, electrical stimulation doubled the numbers of rolling leukocytes and upregulated ICAM-1 expression. After 7 days, increased muscle activity as a result of natural movement also resulted in greater ICAM-1 expression, a 4- to 5-fold increase in rolling leukocyte numbers and a 3-fold increase in stationary adherent leukocytes. Chronic ischemia thus increases ICAM-1 and leukocyte adherence in muscle microcirculation only when combined with contractile activity. Post-capillary venular endothelium may be modified by muscle acidosis when contractions are performed under low flow conditions or by changes in rheological (shear force) factors.
    • Identification and biological applications of rhegnylogically-organized cell penetrating peptides.

      Howl, John D.; Jones, Sarah (Australian Peptide Association, 2007)
      Introduction: Many different cell penetrating peptides (CPPs) have been utilized as vectors to affect the highly efficient intracellular delivery of bioactive moieties. A majority of such studies employ sychnologically-organized tandem combinations of a cargo (message) and a CPP (address). To date, bioactive cargoes have included peptides, proteins and a range of oligonucleotides attached either by direct chemical conjugation or as a component of a larger macromolecular complex. Moreover, a majority of CPPs, including the commonly used sequences Tat and penetratin, are designed to be both biologically and toxicologically inert. More recently, a QSAR-based algorithm has been developed to predict cryptic polycationic CPP motifs within the primary sequences of proteins. As described here, this novel technology has enabled the study of rhegnylogic CPPs in which multiple pharmacophores for cellular penetration and desirable biological activities are discontinuously organized within the primary sequence of single peptide. This organization differs from the more commonly utilized sychnologic strategy which joins functionally discrete and continous address and messages together in a tandem construct.
    • Identification of differentially expressed genes in paediatric ependymoma

      Suarez-Merino, Blanca; Hubank, Mike; Hayward, Richard; Harkness, William; Thompson, Dominic; Phipps, Kim; Revesz, Tamas; Darling, John L.; Thomas, David G.; Warr, Tracy (Society for Neuro-Oncology and Duke University Press, 2003)
      To date, the genetic events that contribute to the pathogenesis of ependymoma are essentially unknown. Furthermore, previous cytogenetic studies have demonstrated that approximately 50% of tumors have no detectable chromosome abnormalities. In this study, we used the Affymetrix GeneChip U95Av2 microarrays to generate gene expression profiles in 11 pediatric ependymoma, comprising 6 fresh frozen samples and 5 short-term cultures. A total of 107 genes were differentially expressed in both the biopsies and cell cultures compared with normal control tissue derived from corpus callosum. The 84 genes with increased expression included many encoding adhesion and extracellular matrix proteins; genes involved in the cell cycle, such as cyclin D1, CDK2, CDK4, and Wee1; transcription factors such as Zic1; and known oncogenes such as c-myc, WNT5A, JUN, TC21, RAB36, and FOP. An interesting group also found to be overexpressed comprises the insulin-like growth factor binding proteins IGFBP2, IGFBP3, and IGFBP4, which may be responsible for the autostimulation of cell growth in these tumors. Of the 23 genes that were underexpressed by 5-fold or less, 6 were of unknown function. Others included the apoptotic control gene ATIP the DAAM1 gene associated with the Wnt/frz oncogenic pathway, and genes involved in vesicle trafficking and recycling within and across cells, such as NPC1, RAB40B, TJP2, and SH3GL3. We have identified a number of candidate genes and genetic pathways that have not previously been associated with the pathogenesis of pediatric ependymoma. Further evaluation of the expression or mutation status of these genes will elucidate their roles in ependymoma development.
    • Identification of extensive genomic loss and gain by comparative genomic hybridisation in malignant astrocytoma in children and young adults.

      Warr, Tracy; Ward, Samantha; Burrows, J.; Harding, Brian; Wilkins, Peter; Harkness, William; Hayward, Richard; Darling, John L.; Thomas, David G. (Wiley Interscience, 2001)
      Although astrocytomas are the most common central nervous system tumours in all age groups, there is substantial evidence that tumours arising in young patients (< 25 years of age) do not have the same genetic abnormalities that are characteristic of tumours in older patients. Furthermore, novel, consistent changes have not been identified in astrocytomas in children and young adults. We analysed 13 malignant astrocytomas from young patients using comparative genomic hybridisation. Regions of genomic imbalance were identified in 10 cases. The most common recurrent copy number aberrations were loss of 16p (54% of cases), 17p (38%), 19p (38%), and 22 (38%) and gain on 2q (38%), 12q (38%), 13 (38%), 4q (31%), 5q (31%), and 8q (31%). Seven regions of high copy number amplification were observed at 8q21-22 (three cases), 7q22-23 (two cases), and 1p21-22, 2q22, 12q13-pter, 12q15-21, and 13q11-14 (one case each). This study provides evidence of new characteristic chromosomal imbalances from which potential candidate genes involved in the development of malignant astrocytoma in children and young adults may be identified.