• Quality control of herbal medicines

      Liang, Yi-Zeng; Xie, Peishan; Chan, Kelvin C. (Elsevier, 2004)
      Different chromatographic and electrophoretic techniques commonly used in the instrumental inspection of herbal medicines (HM) are first comprehensively reviewed. Chemical fingerprints obtained by chromatographic and electrophoretic techniques, especially by hyphenated chromatographies, are strongly recommended for the purpose of quality control of herbal medicines, since they might represent appropriately the "chemical integrities" of the herbal medicines and therefore be used for authentication and identification of the herbal products. Based on the conception of phytoequivalence, the chromatographic fingerprints of herbal medicines could be utilized for addressing the problem of quality control of herbal medicines. Several novel chemometric methods for evaluating the fingerprints of herbal products, such as the method based on information theory, similarity estimation, chemical pattern recognition, spectral correlative chromatogram (SCC), multivariate resolution, etc. are discussed in detail with examples, which showed that the combination of chromatographic fingerprints of herbal medicines and the chemometric evaluation might be a powerful tool for quality control of herbal products.
    • Randomised controlled trial of a home-based physical activity intervention in breast cancer survivors

      Lahart, Ian M.; Metsios, George S.; Nevill, Alan M.; Kitas, George D.; Carmichael, Amtul R. (2016-03-17)
      Background: To improve adherence to physical activity (PA), behavioural support in the form of behavioural change counselling may be necessary. However, limited evidence of the effectiveness of home-based PA combined with counselling in breast cancer patients exists. The aim of this current randomised controlled trial with a parallel group design was to evaluate the effectiveness of a home-based PA intervention on PA levels, anthropometric measures, health-related quality of life (HRQoL), and blood biomarkers in breast cancer survivors. Methods: Eighty post-adjuvant therapy invasive breast cancer patients (age = 53.6 ± 9.4 years; height = 161.2 ± 6.8 cm; mass = 68.7 ± 10.5 kg) were randomly allocated to a 6-month home-based PA intervention or usual care. The intervention group received face-to-face and telephone PA counselling aimed at encouraging the achievement of current recommended PA guidelines. All patients were evaluated for our primary outcome, PA (International PA Questionnaire) and secondary outcomes, mass, BMI, body fat %, HRQoL (Functional assessment of Cancer Therapy-Breast), insulin resistance, triglycerides (TG) and total (TC), high-density lipoprotein (HDL-C) and low-density lipoprotein (LDL-C) cholesterol were assessed at baseline and at 6-months. Results: On the basis of linear mixed-model analyses adjusted for baseline values performed on 40 patients in each group, total, leisure and vigorous PA significantly increased from baseline to post-intervention in the intervention compared to usual care (between-group differences, 578.5 MET-min∙wk−1, p = .024, 382.2 MET-min∙wk−1, p = .010, and 264.1 MET-min∙wk−1, p = .007, respectively). Both body mass and BMI decreased significantly in the intervention compared to usual care (between-group differences, −1.6 kg, p = .040, and −.6 kg/m2, p = .020, respectively). Of the HRQoL variables, FACT-Breast, Trial Outcome Index, functional wellbeing, and breast cancer subscale improved significantly in the PA group compared to the usual care group (between-group differences, 5.1, p= .024; 5.6, p = .001; 1.9 p = .025; and 2.8, p=.007, respectively). Finally, TC and LDL-C was significantly reduced in the PA group compared to the usual care group (between-group differences, −.38 mmol∙L−1, p=.001; and −.3 mmol∙L−1, p=.023, respectively). Conclusions: We found that home-based PA resulted in significant albeit small to moderate improvements in selfreported PA, mass, BMI, breast cancer specific HRQoL, and TC and LDL-C compared with usual care.
    • Reactivity and isotype profiling of monoclonal antibodies using multiple antigenic peptides.

      Waldron, E.E.; Murray, Paul G.; Kolar, Zdenek; Young, Lawrence S.; Brown, C.; Reynolds, Gary; Baumforth, Karl R. N.; Toomey, S.; Astley, S.J.; Perera, Shantha; et al. (New Rochelle (NY): Mary Ann Liebert, Inc., 2002)
      The characterisation of monoclonal antibodies (MAbs) is essential for the development of assay systems particularly where antigens have been developed using synthetic peptides. Indeed some peptide-carrier conjugates fail to induce immune responses and may not generate antibodies that bind to native protein. As an alternative to peptide-carrier conjugates, multiple antigenic peptides (MAPs) have been used for immunization strategies, but with little regard to the characteristics of the MAbs produced. In this study, we used 3 MAPs of Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) to immunise BALB/c mice. Overall, the polyclonal antibody responses from tail bleeds showed that MAPs evoked B-cell responses. However, on screening 144 hybridomas, 24 MAb supernatants exhibited weak to moderate reactivity in enzyme-linked immunosorbant assay (ELISA) and against cell cytospin preparations (B95.8 and AG876 LCL), respectively. Isotype profiling of hybridoma supernatants also showed that 11 out of 24 were IgM. Further characterization of 6 MAbs in Western blotting showed reactivity to recombinant LMP1 and only one MAb (B28D) showed weak reactivity to the malignant cells (Hodgkin/Reed-Sternberg; HRS cells) of an EBV+ Hodgkin's lymphoma using paraffin-embedded tissue. It is probable that these MAPs failed to augment T-cell help and contributed to the production of low affinity (IgM) antibodies. These observations may be of importance to future immunization strategies, where MAPs are used in the production of monoclonal reagents.
    • Recent advances in the engineering of nanosized active pharmaceutical ingredients: Promises and challenges

      Kaialy, Waseem; Al Shafiee, Maen (Elsevier BV, 2015-12-08)
      The advances in the field of nanotechnology have revolutionized the field of delivery of poorly soluble active pharmaceutical ingredients (APIs). Nanosized formulations have been extensively investigated to achieve a rapid dissolution and therefore pharmacokinetic properties similar to those observed in solutions. The present review outlines the recent advances, promises and challenges of the engineering nanosized APIs. The principles, merits, demerits and applications of the current ‘bottom-up’ and ‘top-down’ technologies by which the state of the art nanosized APIs can be produced were described. Although the number of research reports on the nanoparticle engineering topic has been growing in the last decade, the challenge is to take numerous research outcomes and convert them into strategies for the development of marketable products.
    • Reduced expression of endothelial and inducible nitric oxide synthase in a multidrug resistant variant of the MCF-7 human breast cancer cell line.

      Lahiri, M.; Martin, Jan H. (Spandidos Publications Ltd, 2004)
      The purpose of the present study was to investigate expression of endothelial and inducible nitric oxide synthase in the MCF-7 human breast cancer cell line compared to a multidrug resistant variant, MCF-7-ADR. Immunohistochemical investigations demonstrated 51% of MCF-7 cells stained positive for endothelial nitric oxide synthase, with 46% positive for inducible nitric oxide synthase. However, in the breast cancer cell line that was multidrug resistant there was a much lower positive staining for endothelial nitric oxide synthase at 20% and for inducible nitric oxide synthase at 15%. For the multidrug resistant variant, there was also lower nitric oxide production and the band intensity for immunoblotting for endothelial nitric oxide synthase was weaker than for the parent cell line. These results lend further support to the proposal that expression of NOS is negatively associated with human breast cancer progression.
    • Regulation of beta-cell viability and gene expression by distinct agonist fragments of adiponectin

      Brown, James E. P.; Conner, Alex C..; Digby, Janet E.; Ward, Kenya L.; Ramanjaneya, Manjunath; Randeva, Harpal S.; Dunmore, Simon J. (2010)
      Obesity is an established risk factor for type 2 diabetes. Activation of the adiponectin receptors has a clear role in improving insulin resistance although conflicting evidence exists for its effects on pancreatic beta-cells. Previous reports have identified both adiponectin receptors (ADR-1 and ADR-2) in the betacell. Recent evidence has suggested that two distinct regions of the adiponectin molecule, the globular domain and a small N-terminal region, have agonist properties. This study investigates the effects of two agonist regions of adiponectin on insulin secretion, gene expression, cell viability and cell signalling in the rat beta-cell line BRIN-BD11, as well as investigating the expression levels of adiponectin receptors (ADRs) in these cells. Cells were treated with globular adiponectin and adiponectin (15-36)±leptin to investigate cell viability, expression of key beta-cell genes and ERK1/2 activation. Both globular adiponectin and adiponectin (15-36) caused significant ERK1/2 dependent increases in cell viability. Leptin co-incubation attenuated adiponectin (15-36) but not globular adiponectin induced cell viability. Globular adiponectin, but not adiponectin (15-36), caused a significant 450% increase in PDX-1 expression and a 45% decrease in LPL expression. ADR-1 was expressed at a higher level than ADR-2, and ADR mRNA levels were differentially regulated by non-esterified fatty acids and peroxisome-proliferator-activated receptor agonists. These data provide evidence of roles for two distinct adiponectin agonist domains in the beta-cell and confirm the potentially important role of adiponectin receptor agonism in maintaining beta-cell mass.
    • Regulation of uncoupling protein-2 (UCP-2) expression in human glioma cells by peroxisome proliferators-activated receptor (PPAR) agonists

      Brown, James E. P.; Darling, John L.; Dunmore, Simon J.; Bassey, S. (Society for Neuro-Oncology and Duke University Press, 2005)
      Recent studies have suggested that the glitazones, a group of PPAR agonists commonly prescribed as therapy in type 2 diabetes, could have a role in regulation of cell viability in astrocytomas and glioma cell lines, possibly due to a modulation of reactive oxygen species (ROS) production. PPAR agonists are also known to regulate expression of the mitochondrial protein UCP-2, and UCP-2 has a purported role in ROS regulation amongst others. This study investigated the expression of UCP-2 in U251MG glioma cells and its regulation by PPAR agonists. U251MG glioma cells were cultured according to standard methods and treated with PPAR alpha, delta, and gamma agonists (10 μM WY14643, 10 nM PGI2, 10 μM rosiglitazone and 10 nM PGJ2, respectively) for 24 h. Total RNA was subsequently extracted and semiquantitative RT-PCR used to evaluate UCP-2 mRNA expression. Results showed that UCP-2 was expressed in all control and treatment samples and that its expression was regulated differentially by the various PPAR receptor subtype agonists tested. This novel finding that UCP-2 is expressed in glioma cells, and that its expression is regulated by PPAR agonists, suggests a potential mechanism for the cytotoxic effects of glitazones that have been previously reported, and describes a mechanism which could possibly be manipulated as a potential therapeutic avenue in the future.
    • Resistance of medical biofilms

      Brown, Michael R. W.; Smith, Anthony W. (IWA Publishing, 2003)
      This timely book will introduce its readers to the structure and function of biofilms at a fundamental level as determined during the past decade of research, including: Extracellular polymers as the biofilm matrix; Biofilm phenotype (differential gene expression, interspecies signalling); Biofilm ecology; Biofilm monitoring; Resistance of biofilms to antimicrobial agents and Biofilm abatement. (IWA Publishing)
    • Resistin down-regulates insulin receptor expression, and modulates cell viability in rodent pancreatic beta-cells.

      Brown, James E. P.; Onyango, David J.; Dunmore, Simon J. (Elsevier, 2007)
      The adipokine resistin is known to induce insulin resistance in rodent tissues. Increases in adipose tissue mass are known to have a negative effect on pancreatic beta-cell function, although the mechanisms are poorly understood. This study investigated the effects of resistin on insulin secretion, insulin receptor expression and cell viability in pancreatic beta-cells. BTC-6 or BRIN-BD11 cells were treated for 24h with resistin, and insulin receptor expression, insulin secretion and cell viability were measured. Incubation with 40ng/ml resistin caused significant decreases in insulin receptor mRNA and protein expression, but did not affect insulin secretion. At low concentrations, resistin caused significant increases in cell viability. These data implicate resistin as a factor that may regulate beta-cell function/viability, and suggests a potential mechanism by which increased adiposity causes beta-cell dysfunction.
    • Response of short-term cultures derived from human malignant glioma to aziridinylbenzoquinone, etoposide and doxorubicin: an in vitro phase II trial.

      Darling, John L.; Thomas, David G. (Lippincott Williams & Wilkins, Inc., 2001)
      The relative resistance of malignant glioma to chemotherapy makes the identification of new cytotoxic drugs critically important. The use of short-term cultures derived from these tumors to screen drugs at doses that can be attained within human intracranial tumors provides a model system that should be capable of identifying effective drugs suitable for clinical evaluation. The sensitivity of a panel of short-term cultures derived from 22 malignant astrocytoma and four malignant oligodendroglioma was assessed to aziridinylbenzoquinone (AZQ), etoposide and doxorubicin (DOX) using a [(35)S] methione uptake assay. The ID(50) of each culture was compared to the levels of drug which could be achieved in the tumor using standard doses. There was marked heterogeneity between cultures in response to each drug. Whilst there was no evidence that cultures derived from grade III astrocytoma were more sensitive to any of the drugs than cultures derived from grade IV astrocytoma, cultures derived from oligodendroglioma tended to be more sensitive to the alkylating agent AZQ, but not to either of the other drugs. The sensitivity of these short-term cultures at concentrations that can be achieved in situ corresponded well with the clinical efficacy of AZQ and etoposide. Although DOX appeared to be toxic to human gliomas cells in vitro, its limited penetration into the intact brain would seem to preclude its use i.v., but it is likely to be effective if local drug delivery techniques could be employed. The study suggests that short-term cultures derived from malignant glioma should be used to screen investigational agents for potential clinical efficacy.
    • Rheumatoid factors: what's new?

      Westwood, Olwyn M. R.; Nelson, Paul N.; Hay, Frank C. (Oxford: Oxford Journals, 2006)
      Rheumatoid arthritis (RA) is a classic example of an autoimmune disorder, with chronic inflammation of the synovial membrane, and deterioration of cartilage and bone in the affected joints. The resultant pain, loss of function and permanent disability are also associated with increased morbidity and mortality.
    • Role of sexual behavior in the acquisition of asymptomatic Epstein-Barr virus infection: a longitudinal study.

      Woodman, Ciaran; Collins, Stuart; Vavrusova, Nicol; Rao, Ankit; Middeldorp, Jaap; Kolar, Zdenek; Kumari, Angela; Nelson, Paul N.; Young, Lawrence S.; Murray, Paul G. (Lippincott Williams & Wilkins, 2005)
      BACKGROUND: The natural history of Epstein-Barr virus (EBV) infection is poorly defined. We report the prevalence and subsequent incidence of EBV infection in a cohort of sexually active young women and explore the social and sexual determinants of incident infections. METHODS: The study population was drawn from a cohort of young women, who were recruited for a longitudinal study of risk factors for early cervical neoplasia. A case-control analysis, nested within the cohort of 45 women for whom the first EBV sample tested was EBV-negative and who had further follow-up, was undertaken. EBV serostatus was determined in serum with a synthetic peptide-based enzyme-linked immunosorbent assay; EBV DNA was measured in cervical smears with the use of quantitative polymerase chain reaction. RESULTS: Of 1023 women 15-19 years of age included in this analysis, 978 (95.6%) tested positive for antibodies to EBV in their first serum sample. Of 45 women who tested negative, 22 subsequently acquired an asymptomatic EBV infection; the median time to seroconversion was 25 months (range, 1-60 months), and the median age at seroconversion was 18 years (range, 16-21 years). The risk of seroconversion increased with increasing number of sexual partners [compared with 1 partner, odds ratio (OR) was 1.28 for 2 partners and 2.23 for 3 or more; chiTREND 5.02; df 1; P < 0.05] and was greatest when a new sexual partner had been acquired in the 2 years before seroconversion (OR 4.78; chi 4.62; df 1; P < 0.05). EBV DNA was detected in 9 of 14 women who seroconverted and who also provided cervical samples. CONCLUSIONS: In susceptible young women, the acquisition of EBV infection is associated with their sexual behavior.
    • Salinity induced differences in growth, ion distribution and partitioning in barley between the cultivar Maythorpe and its derived mutant Golden Promise

      Wei, Wenxue; Bilsborrow, Paul E.; Hooley, Paul; Fincham, Daron A.; Lombi, Enzo; Forster, Brian P. (Springer Verlag, 2003)
      Dry matter changes and ion partitioning in two near isogenic barley cultivars Maythorpe (relatively salt sensitive) and Golden Promise (relatively salt tolerant) were studied in response to increasing salinity. Although the growth of both cultivars was significantly reduced by exposure to NaCl, the effect was greater in Maythorpe, whilst Golden Promise maintained an increased ratio of young to old leaf blade. Golden Promise maintained significantly lower Na+ concentrations in young expanding tissues compared with Maythorpe. Partitioning of Cl– was evident in that both varieties maintained lower Cl– concentrations in mesophyll than in epidermal cells. Golden Promise maintained higher K+/Na+ and Ca2+/Na+ ratios in young leaf blade and young sheath tissues than Maythorpe when exposed to salt. Differences in ion partitioning and the maintenance of higher K+ and Ca2+ to Na+ ratios, especially in young growing and recently expanded tissues, would appear to be important mechanisms contributing to the improved salt tolerance of Golden Promise.
    • Screening of a HUVEC cDNA library with transplant-associated coronary artery disease sera identifies RPL7 as a candidate autoantigen associated with this disease.

      Linke, A.T.; Marchant, B.; Marsh, P.; Frampton, Geoffrey; Murphy, John J.; Rose, Marlene L. (Wiley InterScience, 2001)
      A HUVEC cDNA library was screened with sera from two patients who had developed transplant-associated coronary artery disease (TxCAD) following cardiac transplantation. A total of six positive clones were isolated from a primary screen of 40 000 genes. Subsequent DNA sequence analysis identified these to be lysyl tRNA synthetase, ribosomal protein L7, ribosomal protein L9, beta transducin and TANK. Another gene whose product could not be identified showed homology to a human cDNA clone (DKFZp566M063) derived from fetal kidney. Full-length constructs of selected genes were expressed as his-tag recombinant fusion proteins and used to screen a wider patient base by ELISA to determine prevalence and association with TxCAD. Of these ribosomal protein L7 showed the highest prevalence (55.6%) with TxCAD sera compared to 10% non-CAD.
    • Signaling pathway of ginsenoside-Rg1 leading to nitric oxide production in endothelial cells.

      Leung, Kar Wah; Cheng, Yuen-Kit; Mak, Nai Ki; Chan, Kelvin C.; Fan, T. P. David; Wong, Ricky N. S. (Elsevier, 2006)
      We here provide definitive evidence that ginsenoside-Rg1, the pharmacologically active component of ginseng, is a functional ligand of the glucocorticoid receptor (GR) as determined by fluorescence polarization assay. Rg1 increased the phosphorylation of GR, phosphatidylinositol-3 kinase (PI3K), Akt/PKB and endothelial nitric oxide synthase (eNOS) leading to increase nitric oxide (NO) production in human umbilical vein endothelial cell. Rg1-induced eNOS phosphorylation and NO production were significantly reduced by RU486, LY294,002, or SH-6. Also, knockdown of GR completely eliminated the Rg1-induced NO production. This study revealed that Rg1 can indeed serve as an agonist ligand for GR and the activated GR can induce rapid NO production from eNOS via the non-transcriptional PI3K/Akt pathway.
    • Simultaneous detection of precore/basal core promoter mutations in hepatitis B virus using arrayed primer extension.

      Ha, Wai-Yan; Lau, Chi-Chiu; Yue, Patrick Y. K.; Hung, Kaman K. M.; Chan, Kelvin C.; Chui, Siu-Hon; Chui, Albert K. K.; Yam, Wing-Cheong; Wong, Ricky N. S. (Adis, 2006)
      BACKGROUND: Hepatitis B is a major disease that causes serious public health problems worldwide. The loss of HBeAg expression due to point mutations or single nucleotide polymorphisms (SNPs) in the precore/basal core promoter region of the hepatitis B virus (HBV) is associated with hepatocellular cirrhosis and carcinoma. Simultaneous screening for these mutations is strongly advocated for monitoring disease development in HBV-infected patients. The aim of this study is to apply arrayed primer extension (APEX) for the detection of HBV SNPs at the precore/basal core promoter. METHODS AND RESULTS: We optimized APEX for simultaneous detection of eight potential sites of SNPs in the precore/basal core promoter region of HBV. The precore/basal core promoter regions of HBV from 36 HBV-infected patients were amplified by PCR. After purification and DNA fragmentation, the short, single-stranded HBV DNA fragments were allowed to hybridize with the oligonucleotides corresponding to the sites of SNPs immobilized on glass slides, followed by incorporation of different fluorescently labeled dideoxynucleotides. This allows fast and unequivocal discrimination between wild-type and mutant genotypes with high dideoxy-nucleotide incorporation efficiency, sensitivity, and specificity. The coexistence of both genotypes was also detected; this was undetected by DNA sequencing. CONCLUSION: The simultaneous detection of SNPs in HBV precore/basal core promoter by APEX enables large-scale diagnostic analysis, which can be extended to the whole HBV genome.
    • Simultaneous qualitative and quantitative analyses of the major constituents in the rhizome of Ligusticum Chuanxiong using HPLC-DAD-MS.

      Yi, Tao; Leung, Kelvin Sze-Yin; Lu, Guang-Hua; Chan, Kelvin C.; Zhang, Hao (Tokyo: The Pharmaceutical Society of Japan, 2006)
      An HPLC-DAD-MS method was developed for the qualitative and quantitative analysis of the major constituents in Chuanxiong (the dried rhizome of Ligusticum chuanxiong Hort). Twenty compounds including phenolic constituents, alkylphthalides and phthalide dimers were identified using online ESI-MS and comparisons with literature data and standard compounds, and six of them were quantified by HPLC-DAD simultaneously. A comprehensive validation of the method including sensitivity, linearity, repeatability and recovery was conducted. The linear regressions were acquired with R(2) > 0.99 and limit of detection (LOD, S/N = 3) values were between 1.5 and 2.5 ng. The repeatability was evaluated by intra- and inter-day assays, and relative standard deviation (RSD) values were reported within 1.87%. The recovery studies for the quantified compounds were observed in the range of 96.36-102.37% with RSD values less than 2.63%. These phenolic constituents and alkylphthalides, the major constituents in Chuanxiong, are generally regarded as the index for the quality assessment of this herb. The overall procedure is accurate and reproducible, which is considered suitable for the qualitative and quantitative analyses of a large number of Chuanxiong samples.
    • Some aspects of toxic contaminants in herbal medicines.

      Chan, Kelvin C. (Elsevier, 2003)
      A World Health Organisation survey indicated that about 70-80% of the world populations rely on non-conventional medicine mainly of herbal sources in their primary healthcare. In recent years, we have witnessed the increasing growth in popularity of over-the-counter (OTC) health foods, nutraceuticals, and medicinal products from plants or other natural sources in developed countries. This indirectly indicates that the public is not satisfied with their orthodox medical (OM) treatment. Such increase in popularity has also brought concerns and fears over the professionalism of practitioners, and quality, efficacy and safety of their treatment methods and products from herbal and natural sources available in the market. Over the past decade several news-catching episodes in developed communities indicated adverse effects, sometimes life threatening, allegedly arisen consequential to taking of OTC herbal products or traditional medicines from various ethnic groups. These OTC products may be contaminated with excessive or banned pesticides, microbial contaminants, heavy metals, chemical toxins, and for adulterated with orthodox drugs. Excessive or banned pesticides, heavy metals and microbial contaminants may be related to the source of these herbal materials, if they are grown under contaminated environment or during collection of these plant materials. Chemical toxins may come from unfavourable or wrong storage conditions or chemical treatment due to storage. The presence of orthodox drugs can be related to unprofessional practice of manufacturers. Some of these environment related factors can be controlled by implementing standard operating procedures (SOP) leading to Good Agricultural Practice (GAP), Good Laboratory Practice (GLP), Good Supply Practice (GSP) and Good Manufacturing Practice (GMP) for producing these medicinal products from herbal or natural sources. The public's belief that herbal and natural products are safer than synthetic medicines can only be ascertained by imposing regulatory standards on these products that should be manufactured using these Good Practices. Using Chinese medicines, as examples, this paper illustrate how advances in chemical and biomedical analysis would help to detect intentional and unintentional toxic contaminants in herbal substances. The paper also summarises how modernization and progress are being carried out to get the best out of Chinese medicines for public healthcare.
    • South Asian ethnicity and material deprivation increase the risk of Epstein-Barr virus infection in childhood Hodgkin's disease.

      Flavell, K.J.; Biddulph, J.P.; Powell, J.E.; Parkes, S.E.; Redfern, D.; Weinreb, M.; Nelson, Paul N.; Mann, J.R.; Young, Lawrence S.; Murray, Paul G. (Nature Publishing Group, 2001)
      In order to further define the factors associated with the observed variations in the Epstein-Barr virus-positive rate in childhood Hodgkin's disease, we have studied the effect of material deprivation (measured by the Townsend score) and ethnic origin on the frequency of Epstein-Barr virus-positivity in 55 cases of childhood Hodgkin's disease, diagnosed between 1981 and 1999, from a multi-ethnic region of the United Kingdom. Epstein-Barr virus status was determined by immunohistochemistry for the Epstein-Barr virus-encoded latent membrane protein-1. 62% of cases were Epstein-Barr virus-positive. Ethnic group was the strongest predictor of Epstein-Barr virus-positivity, with South Asians having a more than 20-fold risk of being Epstein-Barr virus-positive compared with non-South Asians. An increased risk was still present after adjusting for deprivation. Townsend scores were significantly higher (indicating more deprivation) in the Epstein-Barr virus-positive group, particularly in males. The relative risk of Epstein-Barr virus-positivity showed a gradient with increasing Townsend score; the risk being 7-times higher in the most deprived quartile compared with the least deprived group. Although the association between Townsend score and Epstein-Barr virus-positivity was reduced after adjusting for ethnic group, the risk of Epstein-Barr virus-positivity was still 3-times higher in the most deprived compared with the least deprived quartile. In addition, cases having 2 or more siblings were 5-times as likely to be Epstein-Barr virus-positive as those from smaller families. These results provide the first evidence of a strong association between Epstein-Barr virus-positive Hodgkin's disease and South Asian children from the United Kingdom. In addition, deprivation may increase the likelihood of Epstein-Barr virus-positive disease independently of ethnicity.
    • Spectrum of copy number changes in low grade paediatric brain tumours detected by comparative genomic hybdidisation

      Warr, Tracy; Ward, Samantha; Idowu, Michael O.; Gregory, S.; Darling, John L.; Thomas, David G. (Society for Neuro-Oncology and Duke University Press, 2001)
      Several different types of low-grade brain tumours arise predominantly in the paediatric population, including astrocytoma, craniopharygioma and choroid plexus papilloma (CPP). As yet, the genetic events that contribute to their development have not been well defined. We have used comparative genomic hybridisation (CGH) to identify regions of genetic loss and gain in a series of 30 low grade tumours comprising 7 pilocytic astrocytoma (WHO grade I), 12 grade II astrocytoma, 5 craniopharyngioma (WHO grade I) and 6 CPP (WHO grade I). In the group of astrocytoma, there were no detectable regions of genomic imbalance in all 7 grade I tumours and in 9 of 12 grade II tumours. The copy number changes in the remaining 3 cases of grade II astrocytoma were gain of 7p and 12p; loss of 1p, 12q and 22; gain of 2q, 3, 8q and 18q, respectively. Similarly, 4 of 5 craniopharyngioma appeared to have normal CGH profiles, although multiple changes including gain of 4, 6q, 8q and 18q and loss of 17, 20q and 22 were observed in the sixth case. In contrast, copy number aberrations were detected in 3 of 6 CPP. In one tumour, gain of 7 was the sole change, whereas gain of 3q and 6q and loss of 9q and 21 were detected in a second case. However, in the remaining CPP all chromosomes except X and Y were involved in copy number changes with gain of 1, 7, 9, 12, 15, 16, 18, 20 and 22 and loss of the remaining autosomes. Overall, genomic imbalance was detected in only 7 of these low grade tumours and it was not possible to identify consistent regions of loss and gain. Considerably larger numbers of each tumour type need to be analysed in order to elucidate the genetic pathways involved in tumourigenesis.