Adult grade II diffuse astrocytomas are genetically distinct from and more aggressive than their paediatric counterparts.

Diffuse astrocytomas (WHO grade II) typically present as slow-growing tumours showing significant cellular differentiation, but possessing a tendency towards malignant progression. They account for ~10% of all astrocytic tumours, with a peak incidence between 30 and 40 years of age. Median survival is reported as around 6-8 years.

Genome-wide analysis of subependymomas shows underlying chromosomal copy number changes involving chromosomes 6, 7, 8 and 14 in a proportion of cases.

Subependymomas (SE) are slow-growing brain tumors that tend to occur within the ventricles of middle-aged and elderly adults. The World Health Organization classifies these tumors within the ependymoma group. Previous limited analysis of this tumor type had not revealed significant underlying cytogenetic abnormalities.

Lysophosphatidic acid cooperates with 1alpha,25(OH)2D3 in stimulating human MG63 osteoblast maturation.

Osteoblast maturation is partly controlled by the interaction of 1alpha,25(OH)(2)D(3) (D3), an active metabolite of Vitamin D, with other growth factors. The first reports describing the in vitro effect of D3 on human osteoblast differentiation performed experiments in the presence of serum. One potentially exciting candidate that might help explain the D3 responses observed for osteoblasts cultured with serum is lysophosphatidic acid (LPA).

Immunoglobulin light-chain genes in the rhesus macaque II: lambda light-chain germline sequences for subgroups IGLV1, IGLV2, IGLV3, IGLV4 and IGLV5.

The combined processes of immunoglobulin (IG) gene rearrangement and somatic hypermutation allow for the creation of an extremely diverse antibody repertoire. Knowledge of the germline sequence of the IG genes is required so that hypermutation and the affinity matured humoral response can be properly studied. Variable region genes can be arranged into subgroups; in humans, there are 11 IGLV subgroups and 6 IGKV subgroups.

Immunoglobulin light-chain genes in the rhesus macaque I: kappa light-chain germline sequences for subgroups IGKV1, IGKV and IGKV3.

The combined processes of immunoglobulin (IG) gene rearrangement and somatic hypermutation allow for the creation of an extremely diverse antibody repertoire. Knowledge of the germline sequence of the IG genes is required so that hypermutation and the affinity matured humoral response can be properly studied. Variable region genes can be arranged into subgroups; in humans, there are 11 IGLV subgroups and six IGKV subgroups.

Quantitative trait locus mapping based on resampling in a vast maize testcross experiment and its relevance to quantitative genetics for complex traits.

From simulation studies it is known that the allocation of experimental resources has a crucial effect on power of QTL detection as well as on accuracy and precision of QTL estimates. In this study, we used a very large experimental data set composed of 976 F(5) maize testcross progenies evaluated in 19 environments and cross-validation to assess the effect of sample size (N), number of test environments (E), and significance threshold on the number of detected QTL, the proportion of the genotypic variance explained by them, and the corresponding bias of estimates for grain yield, grain moisture, and plant height. In addition, we used computer simulations to compare the usefulness of two cross-validation schemes for obtaining unbiased estimates of QTL effects.

Effect of acupuncture on nausea of pregnancy: a randomized, controlled trial.

Objective: To compare acupuncture with sham (placebo) acupuncture for treatment of nausea of pregnancy.

Methods: In a subject- and observer-masked, randomized, controlled trial in the maternity unit at Exeter Hospital, we gave 55 women between 6 and 10 weeks' gestation genuine, traditional-style acupuncture or sham treatment with a cocktail stick on three or four occasions over 3 weeks. The main outcome measure was nausea score, as determined by subject report on a visual analogue scale in a daily diary.

Teaching biomedical applications to secondary students.

Certain aspects of biomedical engineering applications lend themselves well to experimentation that can be done by high school students. This paper describes two experiments done during a six-week summer internship program in which two high school students used electrodes, circuit boards, and computers to mimic a sophisticated heart monitor and also to control a robotic car. Our experience suggests that simple illustrations of complex instrumentation can be effective in introducing adolescents to the biomedical engineering field.

Efficient marker-based recurrent selection for multiple quantitative trait loci.

We studied the efficiency of recurrent selection based solely on marker genotypes (marker-based selection), in order to increase favourable allele frequency at 50 previously detected quantitative trait loci (QTLs). Two selection procedures were investigated, using computer simulations: (1) Truncation Selection (MTS), in which individuals are ranked based on marker score, and best individuals are selected for recombination; and (2) QTL Complementation Selection (QCS), in which individuals are selected such that their QTL composition complements those individuals already selected. Provided QTL locations are accurate, marker-based selection with a population size of 200 was very effective in rapidly increasing frequencies of favourable QTL alleles.

Nitric oxide production during adjuvant-induced and collagen-induced arthritis.

Objective: To investigate the role of nitric oxide (NO) production and NO synthase (NOS) induction during adjuvant-induced arthritis (AIA) and collagen-induced arthritis (CIA) in Dark Agouti rats.

Methods: Urinary nitrate excretion and immune NOS (INOS) messenger RNA (mRNA) expression were measured in the joint, lymph node, spleen, and liver tissues following the induction of either AIA or CIA.

Results: Urinary nitrate excretion and iNOS mRNA expression increased substantially during joint inflammation in both models of arthritis.

Geodemographic segmentation systems for screening health data.

Aim: To describe how geodemographic segmentation systems might be useful as a quick and easy way of exploring postcoded health databases for potential interesting patterns related to deprivation and other socioeconomic characteristics.

Design And Setting: This is demonstrated using GB Profiles, a freely available geodemographic classification system developed at Leeds University. It is used here to screen a database of colorectal cancer registrations as a first step in the analysis of that data.

Algorithms for reengineering 1991 census geography.

"The availability of GIS [geographic information systems] technology and digital boundaries of census output areas now makes it possible for users to design their own census geography. Three algorithms are described that can be used for this purpose. An Arc/Info implementation is briefly outlined and case studies presented to demonstrate some of the results of explicitly designing zoning systems for use with 1991 [U.

Putting the 1991 census sample of anonymised records on your Unix workstation.

"The authors describe the development of a customised computer software package for easing the analysis of the U.K. 1991 Sample of Anonymised Records.

Methods to evaluate populations for alleles to improve an elite hybrid.

Elite hybrids can be improved by the introgression of favorable alleles not already present in the hybrid. Our first objective was to evaluate several estimators derived from quantitative genetic theory that attempt to quantify the relative number of useful alleles in potential donor populations. Secondly, we wanted to evaluate two proposed ways of determining relatedness of donor populations to the parents of the elite hybrid.

Do interventions that improve immunisation uptake also reduce social inequalities in uptake?

Objective: To investigate whether an intervention designed to improve overall immunisation uptake affected social inequalities in uptake.

Design: Cross-sectional small area analyses measuring immunisation uptake in cohorts of children before and after intervention. Small areas classified into five groups, from most deprived to most affluent, with Townsend deprivation score of census enumeration districts.

Are multidimensional social classifications of areas useful in UK health service research?

Objectives: To show the advantages and disadvantages of a multi-dimensional small area classification in the analysis of child health data in order to measure social inequalities in health and to identify the types of area that have greater health needs.

Design: Health data on children from the district child health information system and a survey of primary school children's height were classified by the census enumeration district of residence using the Super profiles neighbourhood classification.

Setting: County of Northumberland, United Kingdom.

Do inaccuracies in small area deprivation analyses matter?

Objective: To assess the accuracy of computerised matching of postcode to enumeration district (ED) and to determine whether any mismatching reduces the validity of methods to distinguish socioeconomic differences in "small area" deprivation studies.

Design: Computerised and manual matching of postcodes to EDs were compared and the census based Townsend deprivation score was compared with socioeconomic data on individual families.

Setting: County of Northumberland, England, 1989.

Measurement of social inequalities in health and use of health services among children in Northumberland.

Social inequalities in a variety of indicators of child health were measured using a 'small area' geographical method of social classification. Cross sectional analyses of routine child health information and of a population survey of the height of primary school children were used. Social classification was by census enumeration district of residence using the Townsend deprivation score.

Cancer in young people in the north of England, 1968-85: analysis by census wards.

Objective: To determine whether the seeming excess of childhood leukaemia and lymphoma identified in Seascale, Cumbria, UK, remains unusual when put into a wider context.

Design: Analysis of cancer incidence by geographical area.

Setting: The north of England including the Northern and North Western Regional Health Authority regions and the Southport and South Sefton districts of the Mersey Regional Health Authority.

The case for samples of anonymized records from the 1991 census.

"The census of population represents a rich source of social data. Other countries have released samples of anonymized records from their censuses to the research community for secondary analysis. So far this has not been done in Britain.

Measuring child health inequalities using aggregations of Enumeration Districts.

In demonstrating health variations between different areas in a district, it is conventional to use local authority ward-to-ward variations. In rural districts, because wards have small, heterogeneous populations, this method is less useful. We have investigated alternative ways of showing variations in child health by using different aggregations of Enumeration Districts (ED) in a small, sparsely populated rural area.