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Alan Fraser

Publications and source records attributed to Alan Fraser.

9 recordsLinked to original sources
PubMed2006

EAE laboratory standards and accreditation.

Laboratory standards have been set by the European Association of Echocardiography of the European Society of Cardiology, in order to homogenize the practice of echocardiography in Europe and therefore ultimately, to protect patients. These standards have been developed for transthoracic, transesophageal and stress Echocardiography into two levels; the basic level, set to provide basic laboratory standards for an optimal clinical service and the advanced level, which is set to establish a fewer number of advanced laboratories in each country, where by in addition to basic standards, they may be providing extensive teaching and research.

Accreditation↗
PubMed2006

Splicing of NOD2 (CARD15) RNA transcripts.

Mutated variants of NOD2, a cytosolic Toll-like receptor (TLR) that recognizes bacterial peptidoglycan, are responsible for increased susceptibility to Crohn's disease (CD). TLRs and their related plant counterparts, the disease-resistance R proteins, undergo alternative splicing as a means of controlling activity. Here we report that regions of NOD2 RNA transcripts that encode the N-terminal and leucine-rich repeat (LRR) domains are alternatively spliced, potentially creating at least eight putative NOD2 variants. The most common variant is a short truncated isoform designated NOD2-short which terminates at residue position 820 leaving three LRR domains. An N-terminally spliced variant designated NOD2-190 contains only CARD1 and a partial CARD2 domain. The expression of transcripts encoding full-length and alternatively spliced forms of NOD2 was altered in blood mononuclear cells and monocytic cell lines stimulated by bacterial products. NOD2-short and NOD2-190 were inactive and unresponsive to muramyl dipeptide (MDP), but did not antagonize the activity of wild-type NOD2. Alternative splicing of NOD2 transcripts represents a potential mechanism by which the intracellular bacterial sensing activity of NOD2 is altered or down-regulated.

Alternative Splicing↗
PubMed2005

Functional diagnosis of coronary stenosis using tissue tracking provides best sensitivity and specificity for left circumflex disease: experience from the MYDISE (myocardial Doppler in stress echocardiography) study.

AIMS: To evaluate the diagnostic capacity of quantitative analysis of segmental longitudinal myocardial displacement images (tissue tracking, TT) during dobutamine stress echocardiography for the detection of patients with coronary artery disease (CAD). METHODS AND RESULTS: TT-generated colour-coded maps of systolic segmental longitudinal displacement were obtained by post-processing of echocardiographic data from 105 patients with CAD and 90 low risk individuals selected from MYDISE database. Quantitative analysis of the distribution pattern of segmental displacement during dobutamine stress was most successful when a ratio of basal (high amplitude) to apical (low amplitude) colour-coded displacement bands (B/A ratio) was employed. Applied in four different left ventricular sectors, the B/A ratio provided a significant discrimination of patients with CAD (p<0.05 in the anterior and p<0.001 in the inferior wall) as assessed by receiver operating characteristic analysis. The procedure was most sensitive when applied in inferior wall for the detection of left circumflex coronary artery disease, the B/A ratio of 0.8 giving the best combination of sensitivity (77+/-8%) and specificity (77+/-5%) values. CONCLUSION: Quantification of dobutamine stress echocardiography using TT is an efficient diagnostic approach and a valuable additional modality in functional cardiac imaging for the initial identification of patients suspected for CAD.

Adrenergic beta-Agonists↗
PubMed2003

Nurse-led dyspepsia clinic using the urea breath test for Helicobacter pylori.

AIM: To audit the results of a nurse-led dyspepsia clinic. METHODS: Referrals to the Gastroenterology Department at Auckland Hospital for gastroscopy were assessed in a dyspepsia clinic. Initial evaluation included consultation and a urea breath test (UBT). Patients given eradication treatment prior to initial clinic assessment were excluded. Patients with a positive UBT were given eradication treatment and were reviewed two months later for symptom assessment and follow-up UBT. Patients with a negative UBT were usually referred back to the GP. RESULTS: There were 173 patients; mean age 38 years; 73 had a positive UBT (42%). A positive UBT was significantly associated with place of birth (NZ 16%; other place of birth 60%; p = 0.001). If the dominant symptom was epigastric pain 54% had a positive UBT; if it was reflux or bloating 29% were positive, p = 0.005. Forty nine UBT-positive patients had follow-up data and of these 43 had successful eradication (88%). Of patients with successful eradication, 40% had an excellent response, 38% improved, and 22% were not improved. After a mean follow up of 3.3 years 42/173 (24%) patients had a gastroscopy. Of these, 30 were initially UBT negative and 12 were UBT positive (9 had been successfully eradicated). The endoscopic findings were normal in 27, reflux oesophagitis in 13, pyloric stenosis in one, and gastric ulcer (HP+ve) in one. Helicobacter pylori status by biopsy was consistent with the UBT result. One hundred and thirteen patients also had H. pylori serology (Cobas Core, Roche) performed. There were three false negatives (negative predictive value of 94% [51/54]) and seven false positives (positive predictive value of 88% [52/59]). CONCLUSIONS: The urea breath test was found to be useful as part of the initial assessment of selected patients who would otherwise have been referred for endoscopy. It is likely that the need for gastroscopy was reduced, but longer follow up will be required to determine whether or not this effect is simply due to delayed referral. This approach is likely to have value only in patients who have a relatively high chance of being H. pylori positive.

Adult↗
PubMed2002

Endoscopic injection therapy for non-variceal upper gastrointestinal bleeding at Auckland Hospital.

AIM: The aim of this study was to audit the efficacy of endoscopic injection therapy for non-variceal upper gastrointestinal (GI) bleeding at Auckland Hospital. METHODS: The medical records of 183 patients who had undergone endoscopic injection of adrenaline for non-variceal upper GI bleeding at Auckland Hospital between November 1996 and May 1999 were reviewed. RESULTS: Primary haemostasis was achieved in 177 (96.7%) patients and six (3.3%) patients had early surgery due to failure of injection therapy. The overall rate of rebleeding was 18.6%. The rate of rebleeding according to the stigmata seen at the time of endoscopy was 36.8% for patients showing spurting vessel; 24% for active ooze; 18.2% for visible vessel; and 3.2% for adherent clot. Active spurting vessels seen on endoscopy were associated with higher risk of repeat injection (p <0.01) and death (p <0.001). Sixteen (9%) patients had repeat injection. Haemostasis was achieved in all, and no deaths or surgical interventions were observed in this subgroup. CONCLUSIONS: Endoscopic injection therapy is an effective, simple and cheap first-line therapy for non-variceal upper GI bleeding. The repeat injection also appears to be an effective treatment for patients rebleeding after the initial injection therapy.

Aged↗