Novel Test (novel + test)

Distribution by Scientific Domains

Selected Abstracts

A novel method to identify gene,gene effects in nuclear families: the MDR-PDT

E.R. Martin
Abstract It is now well recognized that gene,gene and gene,environment interactions are important in complex diseases, and statistical methods to detect interactions are becoming widespread. Traditional parametric approaches are limited in their ability to detect high-order interactions and handle sparse data, and standard stepwise procedures may miss interactions that occur in the absence of detectable main effects. To address these limitations, the multifactor dimensionality reduction (MDR) method [Ritchie et al., 2001: Am J Hum Genet 69:138,147] was developed. The MDR is wellsuited for examining high-order interactions and detecting interactions without main effects. The MDR was originally designed to analyze balanced case-control data. The analysis can use family data, but requires a single matched pair be selected from each family. This may be a discordant sib pair, or may be constructed from triad data when parents are available. To take advantage of additional affected and unaffected siblings requires a test statistic that measures the association of genotype with disease in general nuclear families. We have developed a novel test, the MDR-PDT, by merging the MDR method with the genotype-Pedigree Disequilibrium Test (geno-PDT)[Martin et al., 2003: Genet Epidemiol 25:203,213]. MDR-PDT allows identification of single-locus effects or joint effects of multiple loci in families of diverse structure. We present simulations to demonstrate the validity of the test and evaluate its power. To examine its applicability to real data, we applied the MDR-PDT to data from candidate genes for Alzheimer disease (AD) in a large family dataset. These results show the utility of the MDR-PDT for understanding the genetics of complex diseases. Genet. Epidemiol. 2006. © 2005 Wiley-Liss, Inc. [source]

A new multiplex assay allowing simultaneous detection of the inhibition of cell proliferation and induction of cell death

Józefa W, sierska-G
Abstract The efficacy of distinct anti-cancer drugs used in the chemotherapy of human malignancies varies between tumor tissues and depends largely on the ability of the therapeutic agents to simultaneously inhibit cell proliferation and to eliminate malignant cells by apoptosis. Especially, detection of early apoptotic changes seems to be important because early stages of apoptosis differ from those of necrosis. Therefore, the development of a novel test allowing fast and concomitant screening of the anti-proliferative and pro-apoptotic action of a number of anti-cancer drugs is of great interest. For this purpose, we choose as an experimental model a well characterized anti-proliferative and pro-apoptotic effect of cisplatin (CP) on human cervical carcinoma HeLaS3 cells. As previously reported, exposure of HeLaS3 to CP resulted in a concomitant inhibition of cell proliferation and induction of apoptosis in a dose- and time-dependent manner. In the present study we performed two independent approaches. In the first approach, we examined the cell proliferation and activity of caspases-3/7 in two separate microtiter plates using the CellTiter-GloÔ Luminescent Cell Viability Assay and the Caspase-GloÔ 3/7 Assay, respectively. In the second approach, we determined the same parameters sequentially in one microtiter plate by a mutiplexing assay using CellTiter-BlueÔ Cell Viability Assay and Caspase-GloÔ 3/7 Assay. The both approaches gave very similar results indicating that this new multiplexing assay offers an important advantage for simultaneous detection of cell number and activation of caspases-3/7. The new multiplexing assay offers a range of benefits over standard assays. © 2005 Wiley-Liss, Inc. [source]

Faecal lactoferrin , a novel test to differentiate between the irritable and inflamed bowel?

Aliment Pharmacol Ther,31, 1365,1370 Summary Background, Distinguishing between inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) can be challenging. Aims, To investigate the utility of faecal lactoferrin as a marker of inflammation in patients with IBD, IBS and controls. Methods, Disease activity in IBD patients was assessed using the modified Harvey,Bradshaw Activity Index. Stool samples were analysed using an ELISA assay. Results, We recruited 137 patients with IBS, 126 with ulcerative colitis (UC) and 104 with Crohn's disease (CD), and 98 healthy volunteers. The median ± IQ lactoferrin concentration (,g/g faecal weight) was 0 ± 1.4 for IBS patients, 6.6 ± 42 for UC patients, 4 ± 12.7 for CD patients and 0.5 ± 2 for healthy controls. Lactoferrin levels were significantly higher in IBD patients compared with IBS/healthy controls (P < 0.001). The median lactoferrin concentrations were significantly higher in active UC & CD patients compared with inactive patients (P < 0.001 and P = 0.002 respectively). The sensitivity, specificity, positive and negative predictive values of lactoferrin in distinguishing active IBD from IBS/healthy controls were 67% and 96%, 87% and 86.8% respectively. Conclusions, Lactoferrin is useful to differentiate between IBD and IBS, and can be used as an adjunct to blood parameters to determine IBD patients who have ongoing inflammation. [source]

Heterozygosity,fitness correlations and associative overdominance: new detection method and proof of principle in the Iberian wild boar

Heterozygosity-fitness correlations (HFC) may result from a genome-wide process , inbreeding , or local effects within the genome. The majority of empirical studies reporting HFCs have attributed correlations to inbreeding depression. However, HFCs are unlikely to be caused by inbreeding depression because heterozygosity measured at a small number of neutral markers is unlikely to accurately capture a genome-wide pattern. Testing the strengths of localized effects caused by associative overdominance has proven challenging. In their current paper, Amos and Acevedo-Whitehouse present a novel test for local HFCs. Using stochastic simulations, they determine the conditions under which single-locus HFCs arise, before testing the strength of the correlation between the neutral marker and a linked gene under selection in their simulations. They used insights gained from simulation to statistically investigate the likely cause of correlations between heterozygosity and disease status using data on bovine tuberculosis infections in a wild boar population. They discover that a single microsatellite marker is an excellent predictor of tuberculosis progression in infected individuals. The results are relevant for wild boar management but, more generally, they demonstrate how single-locus HFCs could be used to identify coding loci under selection in free-living populations. [source]

Eastchester clapping sign: A novel test of parietal neglect,

Lyle W. Ostrow MD
Hand clapping is a motor program mastered in infancy. Inspired by a question posed by an Eastchester High School AP Psychology class, we present a case series of 14 patients with hemispatial neglect who, when asked to clap, repeatedly performed one-handed motions stopping abruptly at the midline of the visual hemispace, as if pantomiming slapping an invisible board. In contrast, hemiplegic patients without neglect will reach across and clap against their plegic hands. This phenomenon provides an easy, rapid, and unambiguous test for neglect, applicable to patients of any ethnicity or age. Ann Neurol 2009;66:114,117 [source]

Fifty years of Australian pediatric gastroenterology

Don Cameron
Abstract When the Gastroenterological Society of Australia (GESA) began 50 years ago there were very few pediatric gastroenterologists in the world. The ,Mother' of Paediatric Gastroenterology was Australian Charlotte (,Charlo') Anderson who established one of the world's first pediatric gastroenterology units in Melbourne in the early 1960s. Her earlier work in Birmingham had identified gluten as the component of wheat responsible for celiac disease and helped separate maldigestion (cystic fibrosis) and mucosal malabsorption. The first comprehensive textbook of Paediatric Gastroenterology was edited by Charlotte Anderson and Valerie Burke in 1975. Rudge Townley succeeded Charlotte Anderson in Melbourne and went on to further develop small bowel biopsy techniques making it a safe, simple, and quick procedure that led to much greater understanding of small bowel disease and ultimately the discovery of Rotavirus by Ruth Bishop et al. and subsequently to Rotavirus immunization. Australian Paediatric Gastroenterology subsequently developed rapidly with units being established in all mainland capital cities by the end of the 1970s. The Australian Society of Paediatric Gastroenterology Hepatology and Nutrition (AuSPGHAN) was established in the 1980s. Australians have contributed significantly in many areas of gastroenterology in infants, children, and adolescents including celiac disease, cystic fibrosis, liver disease, transplantation, gastrointestinal infection, allergy, indigenous health, inflammatory bowel disease, gastrointestinal motility, and the development of novel tests of gastrointestinal function and basic science. There have also been major contributions to nutrition in cystic fibrosis, end-stage liver disease, and intestinal failure. The future of Australian Paediatric Gastroenterology is in good hands. [source]