This paper presents an operational approach to predicting fire growth for wildland fires in Canada. The approach addresses data assimilation to provide predictions in a timely and efficient manner. Fuels and elevation grids, forecast weather, and active fire locations are entered into a fire-growth model; then predicted fire perimeters are mapped and presented on the web. The Moderate Resolution Imaging Spectroradiometer (MODIS) and the National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer (NOAA/AVHRR) satellite-based detection systems are used to detect current wildland fires (referred to as hotspots). For selected regions, fire-growth simulation environments are assembled. Fuel type data from several fire management agencies are available in grid format at a resolution of 100 m or less; in areas where such data are not available, a national fuels map based on Satellite Pour l'Observation de la Terre Vegetation sensor (SPOTVGT) land cover and forest inventory is used. Similarly, terrain data are available from a variety of sources. Current hotspots are used as ignition points while past hotspots are used to delineate area burned. Surface wind, temperature, and dew-point values (forecast by Environment Canada) are used to determine the fire weather conditions at the fire location. A case study of two large fires in Canada consisting of 54 fire simulation days is used to test these hypotheses.

The Canadian Forest Fire Danger Rating System (CFFDRS) is used daily across Canada for evaluating forest fire danger. Fuel-type information is one of the inputs required by the models used in the CFFDRS. In this project, three fuel-type maps with a 25 m resolution were produced for a pilot study area located in Alberta using land cover only; land cover and biomass; and, land cover, biomass and leaf area index data derived from satellite imagery. The relationships between inputs and fuel types were determined mainly by the opinions of forest fire scientists and incorporated into a computer program using fuzzy set methodology. Not all the CFFDRS fuel types could be distinguished using these inputs; three of the coniferous types had to be grouped into one common fuel type. Overall accuracy was between 74 and 83% based on ground-truth comparisons. The most accurate map resulted from land cover and biomass data. Detailed accuracy assessment indicated that the overall accuracy increased up to 86% if ambiguous fuel type identification was considered. No combination of inputs was able to define a fuel type with absolute certainty, which is a reflection of differing expert opinions and the small number of inputs used to produce the maps.

The Fire Monitoring, Mapping and Modelling System (Fire M3) is an initiative of the Canada Centre for Remote Sensing (CCRS) and the Canadian Forest Service (CFS), both agencies of Natural Resources Canada. The goals of Fire M3 are to use low-reso- lution satellite imagery to monitor actively burning fires on a daily basis; to estimate annual area burned; and to model fire behav- ior, biomass consumption, and carbon emissions from fires. Same-day fire products are made available on the Fire M3 web site and have been used for a variety of purposes including national reporting and climate change research. The daily operation of the system during the forest fire season involves 1) satellite image reception in Saskatchewan and Quebec; 2) production of geocod- ed, Canada-wide composite images at CCRS; 3) application of CCRS fire, smoke, and burned-area detection algorithms to pro- duce raw fire products; 4) production of final daily fire products at CFS, including weather-based fire behavior modeling; and 5) dissemination of daily fire products on the Fire M3 web site within 12 hours of satellite reception.

This paper provides an overview of four national forest fire management information systems currently used in Canada. The Canadian forest fire danger rating system (CFFDRS) is a non-spatial system, which provides the science framework for fire danger rating in Canada. The spatial fire management system (sFMS) is a geographic information system based fire management information system that implements two core subsystems of the CFFDRS, along with other models and systems. The sFMS is the spatial engine that has been used to implement both of Canada's national forest fire management information systems, the Canadian wildland fire information system (CWFIS) and the fire monitoring, mapping and modeling system (Fire M3). The CWFIS is Canada's national fire management information system; it presents daily information on fire weather, fire behavior potential and selected upper atmospheric conditions. Fire M3 integrates the use of satellite technology for monitoring and mapping large fire occurrence in Canada. Fire M3 also incorporates information from CWFIS to model the impacts of large forest fires based on fire weather conditions and potential fire behavior.

Loss of heterozygosity on chromosome 22q was detected in 53% of 123 ovarian carcinomas, suggesting the presence of at least one tumour suppressor gene. We have refined the location of one possible tumour suppressor gene to the region between the microsatellite markers D22S299 and CYP2D. Located within this region are the genes SREBP2 (sterol regulatory element binding protein 2) and NAGA (N-acetyl-alpha-D-galactosaminidase). Investigation of the coding exons of these genes by single stranded conformational polymorphism/heteroduplex analysis failed to identify any somatic genetic alterations in 57 ovarian tumours which exhibited LOH on 22q13. The CYP2D gene locus straddles the distal boundary of the candidate region. Germline variants of the active CYP2D6 gene with differing abilities to metabolise specific substrates have been implicated in the development of various cancers. Comparison of the frequency of the two common germline mutations among 258 ovarian tumours and 231 non-cancer controls did not reveal any significant differences between the two groups, This suggests that the known polymorphic variants of CYP2D6 are not involved in ovarian cancer predisposition. We also conclude that neither NAGA nor SREBP2 are likely to be mutated in ovarian carcinomas, Int. J. Cancer 87:798-802, 2000. (C) 2000 Wiley-Liss, Inc.

If genetic testing for breast and ovarian cancer predisposition is to become available within a public health care system there needs to be a rational and cost-effective approach to mutation analysis. We have screened for BRCA1 mutations in 230 women with breast cancer, all from the Wessex region of southern England, in order to establish the parameters on which to base a cost-effective regional mutation analysis strategy. Truncating mutations were detected in 10/155 (6.5%) consecutive cases selected only for diagnosis under the age of 40 (nine of these ten women had a strong family history of breast or ovarian cancer), 3/61 (4.9%) bilateral-breast cancer cases (all three mutations occurring among women for whom the first cancer was diagnosed under 40 years) and 8/30 (26.6%) breast cancer cases presenting to the genetics clinic (for whom a strong family history of breast and/or ovarian cancer was present). Ten different mutations were detected in 17 families, but three of these accounted for 10/17 (59%) of the families. The cost of screening the population for mutations in the entire BRCA1 gene is unacceptably high. However, the cost of screening a carefully selected patient cohort is low, the risk of misinterpretation much less and the potential clinical benefits clearer.

No association of a 306-bp insertion polymorphism in the progesterone receptor gene with ovarian and breast cancer

Endometriosis is a very common gynecological condition in which tissue similar to endometrium proliferates at sites outside the uterine cavity, most commonly the ovary. Although it generally remains a benign condition, malignant transformation has been documented. and it is commonly found in association with endometrioid subtype ovarian cancer. Tumor suppressor genes are commonly altered in ovarian cancers, and the development of endometriosis may involve mutations in the same class of genes. We have investigated this possibility by examining DNA from 40 cases of endometriosis for clonal status, alterations in TP53 and RASK, and allelic losses at candidate ovarian tumor suppressor loci on chromosome arms 6q, 9p, l1q, 17p, l7q, and 22q. The majority of endometriotic cysts were monoclonal, but interestingly, 8 of 10 normal endometrial glands were also monoclonal, demonstrating that both are able to develop from a single progenitor cell. No mutations were detected in TP53 or RASK. Loss of heterozygosity (LOH) was detected on chromosomes 9p (18%), 1lq (18%), and 22q (15%). In total, 11 of 40 (28%) cases demonstrated LOH at one or more of these loci. This study, which is the first to report LOH in endometriosis, supports the notion that tumor suppressor gene inactivation may play a role in the development of at least a subset of cases.

The CDKN2 gene encodes a cell cycle regulatory protein and is located on chromosome 9p21, a region deleted in a wide variety of primary tumours. While mutations in the CDKN2 gene itself are frequently observed in tumour cell lines, they are less common in primary tumours. We have investigated the role of the CDKN2 gene in ovarian cancer by analysis for allelic loss of 9p21 and single-strand conformational polymorphism analysis of exons 1 and 2 of CDKN2 in 67 primary ovarian tumours. Loss of heterozygosity on 9p21 was frequently observed (24/50 informative tumours) and was common in early-stage tumours, suggesting that it is an early event in ovarian tumorigenesis. Homozygous deletion of the CDKN2 gene was detected in only 1 tumour. No somatic or germline mutations were observed in CDKN2, though a codon 140 polymorphism was detected in 2 cases. This suggests that CDKN2 is not involved in ovarian tumorigenesis and that another gene(s) may be the target of the frequent 9p allelic losses observed.

The metastatic potential of a solid tumor is dependent upon its ability to interact with the extracellular matrix. The integrin superfamily is a group of proteins that are fundamental in such interactions and play a major role in cell-cell and cell-matrix adhesion. Localization of the integrin proteins was performed in normal ovary, primary epithelial ovarian tumors and metastatic tumor cells in ascitic samples. Expression of alpha1, alpha3, alpha6 and beta4 was observed on normal ovarian epithelium with variable expression of alpha5. Loss of alpha1 expression by malignant cells in the primary tumors was noted. beta4, a component of the laminin receptor which was strongly expressed by both normal ovary and solid tumor, was absent from the ascitic tumor cells in the majority of cases. There was an associated loss of alpha6 expression, indicating a deficiency of hemidesmosomes in the ascitic tumor cells. This alteration of integrin expression by metastatic malignant epithelial ovarian tumor cells may therefore represent one important mechanism by which metastatic disease occurs.

Frequent loss of heterozygosity (LOH) has been reported on 22q in ovarian carcinoma, implying the presence of a tumour-suppressor gene. The neurofibromatosis type 2 gene (NF2) at 22q12 is a plausible candidate. Analysis of 9 of the 17 exons of NF2 by single-strand conformational polymorphism (SSCP) in 67 ovarian carcinomas did not detect any somatic mutations, suggesting that NF2 is not involved in the pathogenesis of ovarian carcinoma. LOH data support this conclusion and that the putative tumour-suppressor gene lies distal to NF2, beyond D22S283.

Frequent loss of heterozygosity has been described on several chromosomes in ovarian carcinoma (OC), but few tumour suppressor genes (TSGs) have been analysed. Mutations in the GTPase-related domain (GRD) of the TSG NF1 have been described in tumours not usually associated with neurofibromatosis type 1 (NF1). We analysed 36 OCs for mutations in this domain using single-strand conformation polymorphism. The NF1-GRD can downregulate the active form of p21RAS and, therefore, we analysed the same tumours for mutations in RASK. No cases of mutations in NF1-GRD were seen, and only two cases of RASK mutations were found. Thus, activation of the RAS signalling pathway by RASK or NF1 mutations does not appear to be common in OC.

OBJECTIVE:To compare the expression of cell adhesion molecules by endometrium and endometriosis. DESIGN:A comparative study of integrin expression, determined immunohistochemically, in eutopic and ectopic endometrium biopsied synchronously from patients with endometriosis diagnosed at laparoscopy or laparotomy. SETTING:University Departments of Obstetrics and Gynaecology, and Pathology, Southampton; Department of Obstetrics and Gynaecology, Newcastle upon Tyne. SAMPLES:Eighteen paired samples of endometria and endometriosis. RESULTS:A wide distribution of collagen-laminin receptor proteins was demonstrated. alpha 1 integrin expression was limited to secretory endometrium. beta 3 expression was only demonstrated on proliferative endometrium. CONCLUSIONS:Expressions of the integrin proteins differed between the various elements of the endometrium. Cyclical changes in integrin expression also were demonstrated. No difference in cell adhesion molecule expression was seen when comparing endometrial and endometriosis samples.