Development and characterization of polymorphic microsatellite markers in taro (Colocasia esculenta)

Microsatellite-containing sequences were isolated from enriched genomic libraries of taro (Colocasia esculenta (L.) Schott). The sequencing of 269 clones yielded 77 inserts containing repeat motifs. The majority of these (81.7%) were dinucleotide or trinucleotide repeats. The GT/CA repeat motif was the most common, accounting for 42% of all repeat types. From a total of 43 primer pairs designed, 41 produced markers within the expected size range. Sixteen (39%) were polymorphic when screened against a restricted set of taro genotypes from Southeast Asia and Oceania, with an average of 3.2 alleles detected on each locus. These markers represent a useful resource for taro germplasm management, genome mapping, and marker-assisted selection.

Can the Internet be used as a medium to evaluate knee angle?

Telemedicine promises to revolutionize medical care delivery in rural and remote areas. The ability to accurately evaluate physical impairment via the Internet is important to the possible future provision of Internet-based physiotherapy. This study evaluated the reliability and validity of assessing knee range of motion via the Internet. Two therapists evaluated knee angle on a single subject via two methods of assessment: the Internet and the traditional method (face-to-face). Nine random positions of the knee were chosen with the principal examiner performing 20 face-to-face and two sets of 20 Internet measures in each position (n=540). The secondary therapist performed Internet assessments only. The Internet connection was established at a readily available speed of 17 kbit/s. The Internet-based goniometer was found to be a valid tool for measuring both knee flexion and extension angles. It was shown to possess both high intra and inter-rater reliability. Difference average plots of the scores verified the consistency of measurement between both modes of assessment. The successful evaluation of the physical outcome measure of knee range of motion via the Internet assists the further development of Internet-based physiotherapy applications. (C) 2003 Elsevier Science Ltd. All rights reserved.

Quality of Life and Colorectal Cancer: a Review

Objectives: To describe what is known of quality of life for colorectal cancer patients, to review what has been done in the Australian setting and to identify emerging directions for future research to address current gaps in knowledge. Method: A literature search (using Medline, PsychInfo, CINAHL and Sociological Abstracts) was conducted and 41 articles identified for review. Results: Three key areas relating to quality of life in colorectal cancer patients emerged from the literature review: the definition and measurement of quality of life; predictors of quality of life; and the relationship of quality of life to survival. Results of existing studies are inconsistent in relation to quality of life over time and its relationship to survival. Small sample sizes and methodological limitations make interpretation difficult. Conclusions: There is a need for large-scale, longitudinal, population-based studies describing the quality of life experienced by colorectal cancer patients and its determinants. Measurement and simultaneous adjustment for potential confounding factors would productively advance knowledge in this area, as would an analysis of the economic cost of morbidity to the community and an assessment of the cost effectiveness of proposed interventions. Implications: As the Australian population ages, the prevalence of colorectal cancer within the community will increase. This burden of disease presents as a priority area for public health research. An improved understanding of quality of life and its predictors will inform the development and design of supportive interventions for those affected by the disease.

Evaluating plant breeding strategies by simulating gene action and dryland environment effects

Functional genomics is the systematic study of genome-wide effects of gene expression on organism growth and development with the ultimate aim of understanding how networks of genes influence traits. Here, we use a dynamic biophysical cropping systems model (APSIM-Sorg) to generate a state space of genotype performance based on 15 genes controlling four adaptive traits and then search this spice using a quantitative genetics model of a plant breeding program (QU-GENE) to simulate recurrent selection. Complex epistatic and gene X environment effects were generated for yield even though gene action at the trait level had been defined as simple additive effects. Given alternative breeding strategies that restricted either the cultivar maturity type or the drought environment type, the positive (+) alleles for 15 genes associated with the four adaptive traits were accumulated at different rates over cycles of selection. While early maturing genotypes were favored in the Severe-Terminal drought environment type, late genotypes were favored in the Mild-Terminal and Midseason drought environment types. In the Severe-Terminal environment, there was an interaction of the stay-green (SG) trait with other traits: Selection for + alleles of the SG genes was delayed until + alleles for genes associated with the transpiration efficiency and osmotic adjustment traits had been fixed. Given limitations in our current understanding of trait interaction and genetic control, the results are not conclusive. However, they demonstrate how the per se complexity of gene X gene X environment interactions will challenge the application of genomics and marker-assisted selection in crop improvement for dryland adaptation.