Publications by authors named "Dixon G"

Many factors have been individually related to outcome in populations of non-small-cell lung cancer (NSCLC) patients. Factors responsible for the outcome of an individual after surgical resection are poorly understood. We have examined the importance of 'tumour volume' in determining prognosis of patients following resection of NSCLC in a multivariate model.

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Incoming students to the School of Dentistry, University of Otago, were surveyed in 1992, 1993, and 1994. Since 1992 there has been a marked trend for the students to originate from an overseas culture, to have more wealthy parents who support their education, and an increase in the numbers who expect to practice overseas upon graduation. This has implications for workforce planning in New Zealand and raises issues relating to equality of access to tertiary education.

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Bronchial epithelial dysplasia is a non-invasive cellular change often associated with physical or chemical injury and considered a pre-neoplastic lesion in the formation of lung cancer. A series of 39 bronchial dysplasias associated with both neoplastic and non-neoplastic lesions were assessed for expression of markers of differentiation by immunocytochemistry and compared with samples of normal bronchial epithelium. The normal bronchial epithelium studied expressed cytokeratins (CKs) 4, 6, 7, 8, 18, and 19 in all cases; CK 13 in 13 cases; and peanut agglutinin (PNA) in seven cases.

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An in vitro transcription system from the trout testis nuclei was developed to study trout protamine gene expression. The protamine promoter contains, among others, two regulatory elements: 1) a cAMP-responsive element or CRE element (TGACGTCA) which is present in position 5' to TATA box, and 2) GC box (CCGCCC) which is present in position 3' to TATA box. The removal of the CRE-binding protein by titration (by the addition of appropriate oligonucleotides to the incubation mixture) resulted in a decrease in transcription of the protamine gene.

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The purpose of this retrospective study was to examine the relationship between tumor volume and age in resected non-small cell lung cancer (NSCLC). Differences exist in the behavior, growth rate, and metastatic potential of solid tumors in both aged humans and experimental animal models. Data from 669 cases of NSCLC resected between 1980 and 1992 were reviewed (445 males; 224 females; median age 67 years, range 16-86).

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We report the complete DNA sequences of the protamine P1 gene and flanking regions for 13 species of the marsupial family Dasyuridae. The structure of the protamine locus is conserved in dasyurids and consists of two exons (of lengths 142-151 and 47 bp) separated by an intron (208-240 bp). A key feature of the dasyurid intron is a 38-40 bp duplication found in all species examined to date.

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A characteristic feature of the sperm P1 protamines of eutherian mammals is the constant presence of six to nine cysteine residues per molecule. During spermiogenesis these residues become oxidized to form a three-dimensional network of disulfide bridges between, and within, protamine molecules in the sperm chromatin. This covalent cross linking strongly stabilizes eutherian sperm nuclei.

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Adolescent health service usage is a neglected research area. Data are important for planning of services and for prioritizing needs. A sample of 871 18-year-olds was surveyed about its use of health services in the preceding year.

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Although expression of the bcl-2 protein has been investigated in a number of non-haematological malignancies, little is known of its distribution in premalignant lesions. Expression of bcl-2 was investigated immunohistochemically in archival biopsies of normal (n = 8) and dysplastic bronchial epithelium (n = 56) and in 31 bronchial resection margins and their corresponding carcinomas. All dysplasias had lost the prominent basal staining pattern seen in histologically normal epithelium.

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A complete cDNA sequence (1026 bp) and a partial structure of a gene encoding the trout testis chromosomal HMG (high mobility group) 2 protein (HMG-T2) is presented. The deduced protein consists of 214 amino acids and shares over 80% similarity to the trout HMG-1 protein (HMG-T1) as well as to the mammalian or avian HMG-2 proteins. Northern blot analysis revealed two transcripts, a major one of 1.

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We generated diffraction-limited laser radiation that is continuously tunable from 3.1 to 4.4 microm by mixing the output from a Ti:sapphire laser with the intracavity field of a single-frequency, 1.

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Protamine P1 genes have been sequenced following PCR amplification from 11 mammals representing five major mammalian orders: Rodentia (rat and guinea pig), Carnivora (cat and bear), Proboscidea (elephant), Perissodactyla (horse), and Artiodactyla (camel, deer, elk, moose, and gazelle). The predicted amino acid sequence for these genes together with previously reported sequences results in a data set of 25 different P1 genes and 30 different P1 amino acid sequences. The alignment of all these sequences reveals that protamines are amongst the most rapidly diverging proteins studied.

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We report the DNA sequences of protamine P1 genes and flanking regions from 21 mammalian species, including representatives of all extant marsupial orders. The protamine P1 locus in marsupials displays highly conserved 5' and 3' flanking sequences, as well as a highly variable intron. Marsupial protamines examined are distinct from those of eutherian mammals in lacking cysteine residues, a feature that may be correlated with lower stability of marsupial sperm nuclei during chromatin condensation.

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The isoprenoid sterols play a crucial role in the viability of all fungi; those unable to synthesise ergosterol because of inhibition, growth conditions or mutation must take it up from the environment. A range of compound types have been discovered which interfere with the biosynthetic pathway from acetate to ergosterol and these compounds have antifungal actions. Inhibition of several of the steps has yielded agents which have been used with great success as medical and agrochemical agents.

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The objective of this study was to determine the consequences of disrupting spermatozoal chromatin condensation on spermatozoal development and function. The avian protamine, galline, was targeted to spermatids of transgenic mice using the mouse protamine 1 gene promoter. Three transgenic mouse lines were established that expressed galline mRNA at 65%, 120%, and 185% of the level found in rooster testis.

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We studied the morbidity in New Zealand using hospital discharge data from 1980 to 1988, and found a reduced head injury (HI) rate over this time overall, but no change in the rate among Maori males and an increased rate among Maori females. In 1988 the rate was 228/100,000 with peaks among males and females aged under 10, males aged 15-25, and both sexes over 84 years old. The rate among young Maori males was higher than in other groups until the age of 55.

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Objective: To determine the prevalence of autoantibodies to high mobility group (HMG) proteins in systemic sclerosis (SSc).

Methods: One hundred ninety-seven unselected sera from patients diagnosed as SSc (n = 180) or Raynaud's phenomenon (RP) (n = 17) were tested for HMG autoantibodies by ELISA and immunoblotting.

Results: Seventy-one of the 180 (39.

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Perchloric acid extraction of trout testis nuclei revealed the presence of two large high-mobility-group (HMG) proteins, HMG-T1 and HMG-T2. The sequence of a complete cDNA (1407 bp) for trout testis HMG-1 protein (referred as to HMG-T1) has been determined. The deduced HMG-T1 protein contains 203 amino acids with more than 86% similarity to mammalian HMG-1 proteins.

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The properties of diode-pumped lasers with gradient-index (GRIN)-mirror resonators are described. The total loss of typical GRIN elements is measured and is found to be comparable with conventional mirrors. The efficiency, threshold, and modal quality of GRIN-mirror Nd:YAG lasers are shown to compare favorably with conventional designs.

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Bronchial epithelial dysplasia is thought to be a premalignant stage in the evolution of lung cancers. Using the CM-1 polyclonal antibody, we have examined the expression of the p53 protein in a larger series of bronchial dysplasias (n = 60) than hitherto investigated. The p53 protein was detected in 14% of mild, 25% of moderate and 59% of severe dysplasias; increased p53 expression correlated with the severity of dysplasia.

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