Whole body MR imaging in ankylosing spondylitis: a descriptive pilot study in patients with suspected early and active confirmed ankylosing spondylitis

Background  

Ankylosing spondylitis is a chronic inflammatory rheumatic disorder which usually begins in early adulthood. The diagnosis is often delayed by many years. MR imaging has become the preferred imaging method for detection of early inflammation of the axial skeleton in ankylosing spondylitis.     

Predictive value of two-dimensional echocardiographic and hemodynamic measurements on admission with acute myocardial infarction

To identify high-risk patients with acute myocardial infarction, we compared admission values of two-dimensional echocardiography and hemodynamic monitoring. Left ventricular wall motion score (WMS), left ventricular stroke work index (LVSWI), and pulmonary capillary pressure (PCP) were obtained in 77 patients without clinical signs of heart failure. Progression into Killip grade 3 or 4 was found in 16 of 77 patients (21%) within 32 +/- 6 hours (mean +/- 1 standard deviation) after admission. Mean WMS, LVSWI, and PCP in those patients who developed severe pump failure were significantly different from those who did not: 13.4 +/- 4.9 versus 7.3 +/- 4, 30 +/- 4 versus 46 +/- 11 gm/m2, and 21 +/- 8 versus 12 +/- 6 mm Hg, respectively. Sensitivity of WMS of greater than 7 and LVSWI of less than 35 gm/m2 in predicting Killip grade 3 or 4 was 88% and 94%, specificity was 57% and 87%, positive predictive value was 35% and 65%, and negative predictive value was 95% and 98%. Sensitivity of PCP was low (50%). Early identification of patients developing myocardial rupture or reinfarction was limited by both methods. We conclude that echocardiographic examination on admission in patients with acute myocardial infarction provides an alternative approach for early identification of low-risk patients.     

Efficient target-selected mutagenesis in zebrafish

One of the most powerful methods available to assign function to a gene is to inactivate or knockout the gene. Recently,we described the first target-selected knockout in zebrafish. Here,we report on the further improvements of this procedure,resulting in a highly efficient and easy method to do target-selected mutagenesis in zebrafish. A library of 4608 ENU-mutagenized F1 animals was generated and kept as a living stock. The DNA of these animals was screened for mutations in 16 genes by use of CEL-I-mediated heteroduplex cleavage (TILLING) and subsequent resequencing. In total,255 mutations were identified,of which 14 resulted in a premature stop codon,7 in a splice donor/acceptor site mutation,and 119 in an amino acid change. By this method,we potentially knocked out 13 different genes in a few months time. Furthermore,we show that TILLING can be used to detect the full spectrum of ENU-induced mutations in a vertebrate genome with the presence of many naturally occurring polymorphisms.     

Direct amplification and genotyping of Dientamoeba fragilis from human stool specimens

Dientamoeba fragilis is a globally occurring parasite that has been recognized as a causative agent of gastrointestinal symptoms. A single-round PCR was developed to detect D. fragilis DNA directly from human stool samples. The genetic diversity of D. fragilis from 93 patients and 6 asymptomatic carriers was examined by PCR followed by restriction fragment length polymorphism and sequencing of part of the small-subunit rRNA gene. The data show that D. fragilis sequences can be studied directly from fecal specimens despite the absence of a cyst stage and without the need for prior culturing. In addition, the results suggest strongly that D. fragilis shows remarkably little variation in its small-subunit rRNA gene.