Performance of adenosine “stress-only” perfusion MRI in patients without a history of myocardial infarction: a clinical outcome study

To assess the diagnostic value of adenosine “stress-only” myocardial perfusion MR for ischemia detection as an indicator for coronary angiography in patients without a prior myocardial infarction and a necessity to exclude ischemia. Adenosine perfusion MRI was performed at 1.5 T in 139 patients with a suspicion of ischemia and no prior myocardial infarction. After 3 min of adenosine infusion a perfusion sequence was started. Patients with a perfusion defect were referred to coronary angiography (CAG). Patients with a normal perfusion were enrolled in follow-up. Fourteen out of 139 patients (10.1%) had a perfusion defect indicative of ischemia. These patients underwent a coronary angiogram, which showed complete agreement with the perfusion images. 125 patients with a normal myocardial perfusion entered follow-up (median 672 days, range 333–1287 days). In the first year of follow-up one Major Adverse Coronary Event (MACE) occurred and one patient had new onset chest pain with a confirmed coronary stenosis. Reaching a negative predictive value for MACE of 99.2% and for any coronary event of 98.4%. At 2 year follow-up no additional MACE occurred. Sensitivity of adenosine perfusion MR for MACE is 93.3% and specificity and positive predictive value are 100%. Adenosine myocardial perfusion MR for the detection of myocardial ischemia in a “stress-only” protocol in patients without prior myocardial infarctions, has a high diagnostic accuracy. This fast examination can play an important role in the evaluation of patients without prior myocardial infarctions and a necessity to exclude ischemia

The effect of pyramiding Phytophthora infestans resistance genes RPi-mcd1 and RPi-ber in potato

Despite efforts to control late blight in potatoes by introducing Rpi-genes from wild species into cultivated potato, there are still concerns regarding the durability and level of resistance. Pyramiding Rpi-genes can be a solution to increase both durability and level of resistance. In this study, two resistance genes, RPi-mcd1 and RPi-ber, introgressed from the wild tuber-bearing potato species Solanum microdontum and S. berthaultii were combined in a diploid S. tuberosum population. Individual genotypes from this population were classified after four groups, carrying no Rpi-gene, with only RPi-mcd1, with only RPi-ber, and a group with the pyramided RPi-mcd1 and RPi-ber by means of tightly linked molecular markers. The levels of resistance between the groups were compared in a field experiment in 2007. The group with RPi-mcd1 showed a significant delay to reach 50% infection of the leaf area of 3 days. The group with RPi-ber showed a delay of 3 weeks. The resistance level in the pyramid group suggested an additive effect of RPi-mcd1 with RPi-ber. This suggests that potato breeding can benefit from combining individual Rpi-genes, irrespective of the weak effect of RPi-mcd1 or the strong effect of RPi-ber

No efficacy of annual gynaecological screening in BRCA1/2 mutation carriers; an observational follow-up study

BRCA1/2 mutation carriers are offered gynaecological screening with the intention to reduce mortality by detecting ovarian cancer at an early stage. We examined compliance and efficacy of gynaecological screening in BRCA1/2 mutation carriers. In this multicentre, observational, follow-up study we examined medical record data of a consecutive series of 888 BRCA1/2 mutation carriers who started annual screening with transvaginal ultrasonography and serum CA125 between 1993 and 2005. The women were annually screened for 75% of their total period of follow-up. Compliance decreased with longer follow-up. Five of the 10 incident cancers were interval tumours, diagnosed in women with a normal screening result within 3-10 months before diagnosis. No difference in stage distribution between incident screen-detected and interval tumours was found. Eight of the 10 incident cancers were stage III/IV (80%). Cancers diagnosed in unscreened family members had a similar stage distribution (77% in stage III/IV). The observed number of cases detected during screening was not significantly higher than expected (Standardized Incidence Ratio (SIR): 1.5, 95% confidence interval: 0.7-2.8). For the subgroup that was fully compliant to annual screening, a similar SIR was found (1.6, 95% confidence interval: 0.5-3.6). Despite annual gynaecological screening, a high proportion of ovarian cancers in BRCA1/2 carriers are interval cancers and the large majority of all cancers are diagnosed in advanced stages. Therefore, it is unlikely that annual screening will reduce mortality from ovarian cancer in BRCA1/2 mutation carriers