To determine if alterations of trabecular pattern, or the rate of change of jaw trabeculae, are associated with rate of hip fracture.
Participants in a population-based study of residents of a ...California retirement community (Leisure World Cohort Study) were asked for permission to obtain their dental radiographs. Periapical radiographs were retrieved on 598 women (average age at time of first radiograph=77 years). Several measurements of trabecular pattern (strut analysis), textural properties (run-length analysis) and Fourier analysis were made in several anatomical regions of the jaw. These trabecular features and clinical information self-reported by subjects in the early 1980s were examined for association with hip fracture rate using Cox proportional-hazard regression.
Rate of hip fracture increased with decreasing average length of node-to-terminus struts in the mandibular incisor region. Each 0.01 mm per year decrease in the average length of node-to-terminus struts increased hip fracture rate by a factor of 2.9 (P=0.02, accuracy=73%). Inclusion of clinical parameters improved the predictive model compared with use of the radiographic parameter alone (accuracy=79%). Similar results were seen for percent change per year in this parameter.
Changes in radiographic trabecular structure, augmented with clinical information, are predictive of hip fracture in elderly women. Further refinement of both the radiographic and clinical parameters may lead to a screening process accessible to a large number of women and to early diagnosis and treatment of osteoporosis.
Most human sequence variation is in the form of single-nucleotide polymorphisms (SNPs). It has been proposed that coding-region SNPs (cSNPs) be used for direct association studies to determine the ...genetic basis of complex traits. The success of such studies depends on the frequency of disease-associated alleles, and their distribution in different ethnic populations. If disease-associated alleles are frequent in most populations, then direct genotyping of candidate variants could show robust associations in manageable study samples. This approach is less feasible if the genetic risk from a given candidate gene is due to many infrequent alleles. Previous studies of several genes demonstrated that most variants are relatively infrequent (<0.05). These surveys genotyped small samples (n<75) and thus had limited ability to identify rare alleles. Here we evaluate the prevalence and distribution of such rare alleles by genotyping an ethnically diverse reference sample that is more than six times larger than those used in previous studies (n=450). We screened for variants in the complete coding sequence and intron-exon junctions of two candidate genes for neuropsychiatric phenotypes: SLC6A4, encoding the serotonin transporter; and SLC18A2, encoding the vesicular monoamine transporter. Both genes have unique roles in neuronal transmission, and variants in either gene might be associated with neurobehavioral phenotypes.
Linkage disequilibrium (LD) mapping may be a powerful means for genome screening to identify susceptibility loci for common diseases. A new statistical approach for detection of LD around a disease ...gene is presented here. This method compares the distribution of haplotypes in affected individuals versus that expected for individuals descended from a common ancestor who carried a mutation of the disease gene. Simulations demonstrate that this method, which we term “ancestral haplotype reconstruction” (AHR), should be powerful for genome screening of phenotypes characterized by a high degree of etiologic heterogeneity, even with currently available marker maps. AHR is best suited to application in isolated populations where affected individuals are relatively recently descended (<∼25 generations) from a common disease mutation–bearing founder.
Recent interest in using association studies to investigate complex traits has focused attention on understanding linkage disequilibrium (LD) in the human genome. We examined the genome-wide ...distribution and magnitude of such background LD (BLD) using 1036 densely spaced microsatellites, in a sample from the demographically well characterized population of the Central Valley of Costa Rica. High levels of BLD were found between linked markers several centiMorgans apart, and although BLD was significantly related to genetic distance between markers it was not spread uniformly throughout the genome. Understanding the forces governing the distribution of BLD in the genome will require similar investigations using a standard set of markers in other populations.
Background: Obesity has an adverse impact on metabolic parameters including CKD. Bariatric procedures produce significant weight loss compared to non-surgical means and have a positive effect on ...renal and non-renal parameters. The present study retrospectively evaluated the effect of bariatric procedures and weight loss on renal function, proteinuria, hypertension, lipid profile and diabetic status in chronic kidney disease (CKD) patients in Queensland, Australia. Methods: Of the 880 patients who consented to the CKD Registry, data of patients who underwent bariatric procedures were analysed. Changes in anthropometric measures, renal functions, lipid profile, glycosylated haemoglobin A1c (HbA1c) (%), proteinuria and requirement for blood pressure medications and insulin dose were noted during follow-up. Results: Eight patients (1%) (mean age 48 years: there were 5 men) underwent bariatric procedures (gastric banding - four, gastric sleeve - three and gastric bypass - one). Mean follow-up duration was 10 years. During follow-up a trend towards reduction was noted in weight (kg) (163 - 115 p = 0.01), proteinuria (g/mol) (381 - 65 p = 0.302), HbA1c (%) (8.1 to 6.7 p = 0.03) and total cholesterol (mmol/L) (4.7 to 4.0 p = 0.33). The estimated glomerular filtration rate (eGFR) (mL/min/1.73m2) did not change significantly (58.1 - 54.1 p = 0.426). Reductions of anti-hypertensive medications (1.8 - 0.75, p = 0.08) and insulin dose (IU) (61.3 - 25 p = 0.37) were also noted. One patient developed complications requiring removal of the gastric band. One patient progressed to end-stage renal disease. Conclusions: There was significant weight loss leading to improvement in multiple metabolic parameters. There was a trend towards a slow progression of CKD post-bariatric surgery during the follow-up. Although the numbers are small bariatric procedures appears to have a significant role in the management of obesity associated with CKD and related metabolic conditions.
Information systems with an abundance of graphics data are growing rapidly due to advances in data storage technology, the development of multimedia communications across networks, and the fact that ...parallel computers are leading to faster image processing systems.
This book addresses image information retrieval and spatial reasoning using an approach called Symbolic Projection, which supports descriptions of the image content on the basis of the spatial relationships between the pictorial objects. Image information systems have a wide variety of applications, including information retrieval on the World Wide Web, medical pictorial archiving, computer-aided design, robotics, and geographical information systems, and this book is comprehensively illustrated with examples from these areas.
Symbolic Projection now forms the basis of an enormous number and range of information retrieval algorithms, and also supports query-by-picture and qualitative spatial reasoning. Both authors are international experts in the field, and the book will serve as an excellent source for those working in multimedia systems and image information systems who wish to find out more about this exciting area.
Key Features* An all-inclusive source to the field--all you need to know* S-K. Chang is the leading authority in this field, which he pioneered* Includes a wide variety of applications, including information retrieval on the World Wide Web, computer-aided design, and geographical information systems
Manic depressive illness, or bipolar disorder (BP), is characterized by episodes of elevated mood (mania) and depression. We designed a multistage study in the genetically isolated population of the ...Central Valley of Costa Rica to identify genes that promote susceptibility to severe BP (termed BPI), and screened the genome ot two Costa Rican BPI pedigrees (McInnes et al., submitted). We considered only individuals who fulfilled very stringent diagnostic criteria for BPI to be affected. The strongest evidence for a BPI locus was observed in 18q22-q23. We tested 16 additional markers in this region and seven yielded peak lod scores over 1.0. These suggestive lod scores were obtained over a far greater chromosomal length (about 40 cM) than in any other genome region. This localization is supported by marker haplotypes shared by 23 of 26 BPI affected individuals studied. Additionally, marker allele frequencies over portions of this region are significantly different in the patient sample from those of the general Costa Rican population. Finally, we performed an analysis which made use of both the evidence for linkage and for association in 18q23, and we observed significant lod scores for two markers in this region.
Underground mines require fool-proof, mine-wide communication systems for smooth functioning of mine production and worker safety. Proper and reliable communication systems not only decrease machine ...break down time, but more importantly provide immediate transmission of messages from the underground working area to the surface for normal mining operations as well as necessary rescue operations in case of disaster. Therefore, a reliable and effective communication system is an essential requisite for safe working, and maintaining the requisite production and productivity of underground mines. Existing wired communication systems cannot reach parts of complex mines, and are ineffective in many disaster situations. Wireless Communication in Underground Mines focuses on the recent advancement in wireless communication technologies for underground mines and other hazardous areas. This comprehensive book provides a unified foundation of wireless communication systems for transmission of data, voice and video. The book also incorporates intrinsically safe design and development aspects of circuits, which are essential for underground mines and hazardous areas. The book consists of recent wireless communication technologies designed and developed by the authors for underground mines and draws upon their experiences in the fields. Wireless Communication in Underground Mines covers a wide range of the recent practices of wireless communication systems as well as wireless sensor networking, radio frequency identification devices, system specific embedded software, application software, and designing and developing techniques for intrinsic safe circuits.
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