Patient-Specific Minimal Residual Disease Primers Amplify with Uniformly High Efficiency.

The widespread use of PCR to quantify minimal residual disease has been hampered by the apparently wide variation in amplification efficiency (AE) of PCR primers. A new method to measure AE was developed on the basis of the Ct results of PCR amplification of single copies of a target molecule placed by limiting dilution into wells of a microplate. The mean one copy Ct of a population of primers or of a reference primer was calibrated against the AE determined by the standard method of regression analysis. The AE of a test primer could then be determined by relating its one copy Ct value to the calibrated mean one copy Ct value. This new method was much more precise than direct determination of AE by regression analysis. The AE of minimal residual disease primers, and of primers for eight other genes, was determined to be >95% and often close to 100%. A primer/plasmid standard was produced to enable transfer of the method to other laboratories. The one copy Ct method thus enables AE of a patient-specific primer to be simply and accurately determined.

Deviations of acoustic low-level descriptors in speech features of a set of triplets, one with autism.

Verbal speech of children diagnosed with ASD is explored in order to identify patterns autism has left in speech, and to model such patterns for implementing automatic diagnostic and screening frameworks. In this study, we identify the deviations of acoustic low-level descriptors (LLDs) in voice of an autistic adolescent from her typically developing triplet siblings. The goal is to identify the atypicality in voice introduced by autism under minimum gender, age, genetic, and language bias and use the gained insights to build a more generalized model by adding more subjects hierarchically. We report the most significant LLDs that describe the deviations of acoustic features due to autism for categories of utterances and feature groups.

BCR-ABL1 expression, RT-qPCR and treatment decisions in chronic myeloid leukaemia.

AIMS: RT-qPCR is used to quantify minimal residual disease (MRD) in chronic myeloid leukaemia (CML) in order to make decisions on treatment, but its results depend on the level of BCR-ABL1 expression as well as leukaemic cell number. The aims of the study were to quantify inter-individual differences in expression level, to determine the relationship between expression level and response to treatment, and to investigate the effect of expression level on interpretation of the RT-qPCR result. METHODS: BCR-ABL1 expression was studied in 248 samples from 65 patients with CML by determining the difference between MRD quantified by RT-qPCR and DNA-qPCR. The results were analysed statistically and by simple indicative modelling. RESULTS: Inter-individual levels of expression approximated a normal distribution with an SD of 0.36 log. Expression at diagnosis correlated with expression during treatment. Response to treatment, as measured by the number of leukaemic cells after 3, 6 or 12 months of treatment, was not related to the level of expression. Indicative modelling suggested that interpretation of RT-qPCR results in relation to treatment guidelines could be affected by variation in expression when MRD was around 10% at 3 months and by both expression variation and Poisson variation when MRD was around or below the limit of detection of RT-qPCR. CONCLUSIONS: Variation between individuals in expression of BCR-ABL1 can materially affect interpretation of the RT-qPCR when this test is used to make decisions on treatment.

A DNA real-time quantitative PCR method suitable for routine monitoring of low levels of minimal residual disease in chronic myeloid leukemia.

The BCR-ABL1 sequence has advantages over the BCR-ABL1 transcript as a molecular marker in chronic myeloid leukemia and has been used in research studies. We developed a DNA real-time quantitative PCR (qPCR) method for quantification of BCR-ABL1 sequences, which is also potentially suitable for routine use. The BCR-ABL1 breakpoint was sequenced after isolation by nested short-range PCR of DNA from blood, marrow, and cells on slides, obtained either at diagnosis or during treatment, or from artificial mixtures. PCR primers were chosen from a library of presynthesized and pretested BCR (n = 19) and ABL1 (n = 568) primers. BCR-ABL1 sequences were quantified relative to BCR sequences in 521 assays on 266 samples from 92 patients. For minimal residual disease detectable by DNA qPCR and RT-qPCR, DNA qPCR gave similar minimal residual disease results as RT-qPCR but had better precision at low minimal residual disease levels. The limit of detection of DNA qPCR depended on the amount of DNA assayed, being 10(-5.8) when 5 µg was assayed and 10(-7.0) when 80 µg was assayed. DNA qPCR may be useful and practical for monitoring the increasing number of patients with minimal residual disease around or below the limit of detection of RT-qPCR as the assay itself is simple and the up-front costs will be amortized if sequential assays are performed.

Effect of augmented sensorimotor input on learning verbal and nonverbal tasks among children with autism spectrum disorders.

Thirty-four children, with autism spectrum disorders, ages 4-14 years, were matched and randomly assigned to one of two conditions for learning a novel juice-making task and producing two novel words about the event. Seventeen sighted children were manually guided to perform the task and tactually prompted during imitated productions of novel words for the event. Their matched controls heard the novel words and watched the juice-making task being performed. Performances on four verbal and two nonverbal measures right after instruction and at 24-48 h post-instruction, revealed higher scores for the ''hands-on'', participation than observation group on both verbal and nonverbal tasks. This study offers a paradigm for exploring the instructional advantage of enhanced participatory experience.

Monitoring and feedback of hand hygiene compliance and the impact on facility-acquired methicillin-resistant Staphylococcus aureus.

In 2006, we began monitoring hand hygiene compliance by direct observation. In 2006, with no changes in the methicillin-resistant Staphylococcus aureus (MRSA) control program, a 38% reduction of facility-acquired rates for this organism was realized. These results indicate that focused monitoring of hand hygiene can reduce facility-acquired rates of MRSA.

Impact of implementing a method of feedback and accountability related to contact precautions compliance.

BACKGROUND: In January 2002, Infection control professionals for Spartanburg Regional Healthcare System held a planning retreat focused on patient safety. The main challenge discussed was the control of antibiotic-resistant organisms. Rounds on the patient care units had revealed compliance issues with the current isolation procedures. The team developed a process improvement project coined the Effective Processes in Infection Control Project (EPIC). With a broad challenge of antibiotic resistance, the focus was narrowed to isolation precautions for methicillin-resistant Staphylococcus aureus (MRSA). METHODS: The initial stage of the EPIC project was education, followed by routine unit rounds to monitor compliance. A tool was developed to provide immediate feedback for the nursing units. Summary reports were generated for clinical directors as a method of accountability for unit leadership. Rates for facility-acquired MRSA were monitored and compared with MRSA days at risk. RESULTS: Over a 1-year period of increased accountability, the facility-acquired rate of MRSA decreased by 30%, even though the days at risk increased. The decrease was maintained during year 2. CONCLUSIONS: The results of this project point to the importance of accountability with isolation precautions in the effort to combat the spread of MRSA in the hospital setting.