Biomedical subjects

Helen O'Sullivan

Publications and source records attributed to Helen O'Sullivan.

3 recordsLinked to original sources

PubMed2004

Insights from ambulatory blood pressure monitoring: diagnosis of hypertension and diurnal blood pressure in renal transplant recipients.

BACKGROUND: Accurate diagnosis of hypertension is essential in chronic kidney disease patients, as it is linked to increased left ventricular mass, stroke, cardiovascular mortality and morbidity, and progression to end-stage renal disease. Elevated blood pressure (BP) detected by ambulatory BP monitoring (ABPM) has been shown to be predictive of worse outcome in chronic kidney disease patients. Another predictor of worse outcome is diurnal BP variation, measured also by ABPM. In this study, the authors examined the relationship (concordance or discordance) between blood pressure measured by ABPM compared with daytime office BP, and also explored the predictors of diurnal variation in renal transplant recipients. METHODS: All the patients who underwent renal transplantation and follow-up at the authors' institution from January 1998 to January 2003 were involved in this study (n=177) in addition to another randomly selected 64 patients that underwent transplantation before 1998. All patients had their ABPM performed according to previously described protocols at least 2 weeks after discharge from the hospital, dialysis-independent and with a functioning renal allograft. RESULTS: The authors found a positive correlation between systolic BP (SBP) diurnal variation and age (r =0.263, P <0.0001), glomerular filtration rate (GFR) (r =-0.229, P <0.0001), cyclosporine trough (r =0.171, P =0.047), and ABPM-to-transplant interval (r =-0.133, P =0.039). After fitting a regression model, the authors found that only GFR (P <0.0001) and age (P =0.001) were independent predictors of SBP diurnal variation (r =0.357). Concordance rate between casual BP and ABPM was 80%, and by using casual BP, only 15% of hypertensive renal transplant patients would be erroneously diagnosed as normotensive. CONCLUSIONS: The authors found that SBP diurnal variation is predicted independently by age and GFR, although it does correlate with cyclosporine trough and ABPM-to-transplant interval. In addition, the authors showed that ABPM is a more sensitive method for diagnosing hypertension than is sole reliance on office BP in renal transplant recipients.

Blood Pressure Monitoring, Ambulatory↗

PubMed2004

Bronchial auscultation: an effective adjunct to speech and language therapy bedside assessment when detecting dysphagia and aspiration?

Detection of aspiration by bedside examination has frequently been found to be clinically inadequate when compared with videofluoroscopy (VF) as the gold standard. In Doncaster, UK, a new multidisciplinary approach to bedside assessment was devised using physiotherapists (PT) performing bronchial auscultation (BA) in combination with the speech and language therapists' (SLT) clinical examination of dysphagia. In this study 105 patients referred for VF examination of dysphagia were first tested by the BA team. Comparison was made between the results of the VF team and the results of the BA team in classifying the patients as "aspirating" or at "risk of aspirating." A high degree of agreement was found for risk of aspiration (sensitivity 87%), although specificity was low (37%). BA was highly specific (88%) when confirming the absence of aspiration, but sensitivity to the presence of aspiration was 45%. From the 105 patients tested, the BA team would have failed to modify the diet in only one subject who was aspirating and would have unnecessarily modified the diet of 17 subjects. In conclusion, in the sample population of individuals with complex dysphagia, the BA team approach reliably detected patients identified by VF as at risk of aspiration. In the group of patients identified by VF as aspirating, the BA team proved unreliable in detecting the presence of aspiration, although it did reliably identify patients who were not aspirating. BA is a potentially useful clinical tool which requires further research.

Adolescent↗

PubMed2003

Mining for single nucleotide polymorphisms and insertions/deletions in maize expressed sequence tag data.

We have developed a computer based method to identify candidate single nucleotide polymorphisms (SNPs) and small insertions/deletions from expressed sequence tag data. Using a redundancy-based approach, valid SNPs are distinguished from erroneous sequence by their representation multiple times in an alignment of sequence reads. A second measure of validity was also calculated based on the cosegregation of the SNP pattern between multiple SNP loci in an alignment. The utility of this method was demonstrated by applying it to 102,551 maize (Zea mays) expressed sequence tag sequences. A total of 14,832 candidate polymorphisms were identified with an SNP redundancy score of two or greater. Segregation of these SNPs with haplotype indicates that candidate SNPs with high redundancy and cosegregation confidence scores are likely to represent true SNPs. This was confirmed by validation of 264 candidate SNPs from 27 loci, with a range of redundancy and cosegregation scores, in four inbred maize lines. The SNP transition/transversion ratio and insertion/deletion size frequencies correspond to those observed by direct sequencing methods of SNP discovery and suggest that the majority of predicted SNPs and insertion/deletions identified using this approach represent true genetic variation in maize.

Base Sequence↗