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The aim of this study was to compare the frequency of human leukocyte antigen (HLA) genotypes in 1-18-year-old patients with type 1 diabetes newly diagnosed in 1986-1987 (n = 430), 1996-2000 (n = 342) and in 2003-2005 (n = 171). We tested the hypothesis that the HLA DQ genotype distribution changes over time. Swedish type 1 diabetes patients and controls were typed for HLA using polymerase chain reaction amplification and allele specific probes for DQ A1* and B1* alleles. The most common type 1 diabetes HLA DQA1*-B1*genotype 0501-0201/0301-0302 was 36% (153/430) in 1986-1987 and 37% (127/342) in 1996-2000, but decreased to 19% (33/171) in 2003-2005 (P \ 0.0001). The 0501-0201/0501-0201 genotype increased from 1% in 1986-1987 to 7% in 1996-2000 (P = 0.0047) and to 5% in 2003-2005 (P > 0.05). This study in 1-18-year-old Swedish type 1 diabetes patients supports the notion that there is a temporal change in HLA risk.

In a large case-control study of Swedish incident type I diabetes patients and controls, 0-34 years of age, we tested the hypothesis that the GIMAP5 gene, a key genetic factor for lymphopenia in spontaneous BioBreeding rat diabetes, is associated with type I diabetes; with islet autoantibodies in incident type I diabetes patients or with age at clinical onset in incident type I diabetes patients. Initial scans of allelic association were followed by more detailed logistic regression modeling that adjusted for known type I diabetes risk factors and potential confounding variables. The single nucleotide polymorphism (SNP) rs6598, located in a polyadenylation signal of GIMAP5, was associated with the presence of significant levels of IA-2 autoantibodies in the type I diabetes patients. Patients with the minor allele A of rs6598 had an increased prevalence of IA-2 autoantibody levels compared to patients without the minor allele (OR=2.2; Bonferroni-corrected P=0.003), after adjusting for age at clinical onset (P=8.0 x 10(-13)) and the numbers of HLA-DQ A1*0501-B1*0201 haplotypes (P=2.4 x 10(-5)) and DQ A1*0301-B1*0302 haplotypes (P=0.002). GIMAP5 polymorphism was not associated with type I diabetes or with GAD65 or insulin autoantibodies, ICA, or age at clinical onset in patients. These data suggest that the GIMAP5 gene is associated with islet autoimmunity in type I diabetes and add to recent findings implicating the same SNP in another autoimmune disease.

SUMO4 M55V, located in IDDM5, has been a focus for debate because of its association to type I diabetes (TIDM) in Asians but not in Caucasians. The current study aims to test the significance of M55V association to TIDM in a large cohort of Swedish Caucasians, and to test whether M55V is associated in those carrying human leukocyte antigen (HLA) class II molecules. A total of 673 TIDM patients and 535 age- and sex-matched healthy controls were included in the study. PCR-RFLP was performed to identify the genotype and allele variations. Our data suggest that SUMO4 M55V is not associated with susceptibility to TIDM by itself. When we stratified our patients and controls based on heterozygosity for HLA-DR3/DR4 and SUMO4 genotypes, we found that presence of SUMO4 GG increased further the relative risk conferred by HLA-DR3/DR4 to TIDM, whereas SUMO4 AA decreased the risk. From the current study, we conclude that SUMO4 M55V is associated with TIDM in association with high-risk HLA-DR3 and DR4, but not by itself.

Abstract In today's competitive environment in the oilfield industry, the end-user must choose the very lowest-cost material that will meet the technical needs of the application. This requirement is passed on to the manufacturer, who must use materials that are appropriate yet still meet economic criteria. Another factor has been the expansion of field development into deeper, more corrosive environments, increasing the demand for corrosion-resistant alloys (CRAs) at a time when the demand and cost for stainless materials has increased. In expandable sand control systems, an added burden to the manufacturer is that this new technology must compete with existing non-expandable screens that are low-cost to manufacture with commodity type raw materials. One such example is 13Cr, being the first choice in a CRA for the base pipe in conventional sand screens. Although 13Cr is one of the least costly of the CRAs, it does provide the necessary corrosion resistance in mild H2S environments under a variety of chloride/temperature conditions. However, it lacks the ductility needed for 20 to 25% expansion as a solid expandable. 316L or UNS S31603 is a commodity CRA material with sufficient ductility and strength for use as an expandable screen base pipe, but its corrosion resistance is often questioned; particularly its resistance to chloride stress-corrosion cracking (SCC). This paper provides the data necessary to establish a performance envelope for S31603 and discusses the potential application of the material in several projects. Thus, S31603 is shown to provide a cost-effective CRA material for base pipes in sandcontrol screens. Introduction In expandable screen systems, the capability exists for the screen to be expanded against the borehole ID, virtually eliminating the annulus around the screen and the need for gravel packing. Also, this increases the sand screen surface area, thus reducing pressure drop across the filter and increasing production rates. Because of its high strength, the expanded screen can provide superior support to stabilize the borehole, which then minimizes the potential for sand production(1). Finally, expandable screens can provide a larger production ID than is normally possible with traditional screens. The challenge with the expandable concept has been to provide not only materials that can maintain integrity in the more corrosive environments now being developed but also materials that provide the economic feasibility to allow them to be competitive in today's marketplace. The base pipe of a conventional, non-expanding sand screen is simply a pipe that has been perforated to allow fluid to flow in from the surrounding wellbore. The basic concept behind "solid expansion" of a screen system is simply to expand this perforated pipe downhole and thereby only slightly reduce the collapse strength as a result of having increased the diameter and reduced the wall. In contrast, a slotted pipe that has long thin slots cut lengthwise in the pipe has very little collapse strength after expansion. Therefore, while slotted pipe is easy to expand, it is also easy to collapse, and thus, is unable to prevent the wellbore from caving in.