Citations

Background— Although segmental or circumferential ablation is effective in eliminating pulmonary vein (PV)–mediated atrial fibrillation (AF), this procedure may be complicated by the occurrence of PV stenosis. Methods and Results— To establish the clinical presentation, diagnostic manifestations, and interventional management of PV stenosis, 23 patients with stenosis of 34 veins complicating ablation of AF were evaluated. Each patient became symptomatic 103±100 days after undergoing ablation. In 8 veins, the ablation producing the PV stenosis was a repeated procedure for continued AF. Nineteen patients presented with dyspnea on exertion, 7 with dyspnea at rest, 9 with cough, and 6 with chest pain. On multirow spiral computed tomography examination, the narrowest lumen of the affected PVs measured 3±2 mm compared with 13±3 mm at baseline ( P ≤0.001). The relative perfusion of affected lung segments on isotope scans was reduced to 4±3% of total perfusion compared with 22±10% in unaffected segments. At percutaneous intervention, these veins showed 80±13% stenosis, with a mean gradient of 12±5 mm Hg. This was significantly reduced to a residual stenosis of 9±8% ( P ≤0.001) and a residual gradient of 3±4 mm Hg ( P ≤0.001). Twenty veins were treated with balloon dilatation alone, whereas 14 veins were stented with standard 10-mm-diameter bare-metal stents. Although the symptomatic response was nearly immediate and impressive, 14 patients developed in-stent or in-segment restenosis, requiring repeated interventions in 13. Conclusions— Percutaneous intervention produces rapid and dramatic symptom relief in patients with highly symptomatic PV stenosis after radiofrequency ablation for AF. Nevertheless, alternative treatment methods will be required to decrease recurrent in-stent or in-segment restenosis.

Forkhead transcription factors FOXO1 (FKHR), FOXO3a (FKHRL1), and FOXO4 (AFX) play a pivotal role in tumor suppression by inducing growth arrest and apoptosis. Loss of function of these factors due to phosphorylation and proteasomal degradation has been implicated in cell transformation and malignancy. However, the ubiquitin ligase necessary for the ubiquitination of the FOXO factors and the relevance of this regulation to tumorigenesis have not been characterized. Here we demonstrate that Skp2, an oncogenic subunit of the Skp1/Cul1/F-box protein ubiquitin complex, interacts with, ubiquitinates, and promotes the degradation of FOXO1. This effect of Skp2 requires Akt-specific phosphorylation of FOXO1 at Ser-256. Moreover, expression of Skp2 inhibits transactivation of FOXO1 and abolishes the inhibitory effect of FOXO1 on cell proliferation and survival. Furthermore, expression of the FOXO1 protein is lost in a mouse lymphoma model, where Skp2 is overexpressed. These data suggest that the Skp2-promoted proteolysis of FOXO1 plays a key role in tumorigenesis.

Background— Observed rates of restenosis after drug-eluting stenting are low (<10%). Identification of a reliable and powerful angiographic end point will be useful in future trials. Methods and Results— Late loss (postprocedural minimum lumen diameter minus 8-month minimum lumen diameter) was measured in the angiographic cohorts of the SIRIUS (n=703) and E-SIRIUS (n=308) trials. Two techniques, the standard normal approximation and an optimized power transformation, were used to predict binary angiographic restenosis rates and compare them with observed restenosis rates. The mean in-stent late loss observed in the SIRIUS trial was 0.17±0.45 mm (sirolimus) versus 1.00±0.70 mm (control). If a normal distribution was assumed, late loss accurately estimated in-stent binary angiographic restenosis for the control arm (predicted 35.4% versus observed 35.4%) but underestimated it in the sirolimus arm (predicted 0.6% versus observed 3.2%). Power transformation improved the reliability of the estimate in the sirolimus arm (predicted 3.2% [CI 1.0% to 6.7%]) with similar improvements in the E-SIRIUS trial (predicted 4.0% [CI 1.2% to 7.0%] versus observed 3.9%). In the sirolimus-eluting stent arm, in-stent late loss correlated better with target-lesion revascularization than in-segment late loss (c-statistic=0.915 versus 0.665). Conclusions— Because distributions of late loss with a low mean are right-skewed, the use of a transformation improves the accuracy of predicting low binary restenosis rates. Late loss is monotonically correlated with the probability of restenosis and yields a more efficient estimate of the restenosis process in the era of lower binary restenosis rates.

Abstract Mantle-cell lymphoma (MCL) is a unique subtype of B-cell non-Hodgkin lymphoma (NHL) that behaves aggressively and remains incurable. In order to understand the pathogenesis of MCL and design new therapies, it is important to accurately analyze molecular changes in pathways dysregulated in MCL. We used antibody microarrays to compare patterns of protein expression between CD19+ purified B lymphocytes from normal tonsil and 7 cases of histologically confirmed MCL. Protein overexpression was defined as a higher than 1.3-fold or 2-fold increase in at least 67% of tumor samples compared with normal B-cell control. Of the polypeptides, 77 were overexpressed using the higher than 1.3-fold cutoff, and 13 were overexpressed using the 2-fold cutoff. These included cell cycle regulators (regulator of chromosome condensation 1 [RCC1], murine double minute 2 [MDM2]), a kinase (citron Rho-interacting kinase [CRIK]), chaperone proteins (heat shock 90-kDa protein [Hsp90], Hsp10), and phosphatase regulators (A-kinase anchor protein 1 [AKAP149], protein phosphatase 5 [PP5], and inhibitor 2). The elevated expression of some of these polypeptides was confirmed by immunoblotting and immunohistochemistry, whereas elevated expression of others could not be confirmed, illustrating the importance of confirmatory studies. This study describes a novel technique that identifies proteins dysregulated in MCL.

Background— Sirolimus-eluting stents (SESs) reduce angiographic restenosis in patients with focal, native coronary artery stenoses. This study evaluated the usefulness of SESs in complex native-vessel lesions at high risk for restenosis. Methods and Results— Angiographic follow-up at 240 days was obtained in 701 patients with long (15- to 25-mm) lesions in small-diameter (2.5- to 3.5-mm) native vessels who were randomly assigned to treatment with SESs or bare-metal stents (BMSs) in the SIRIUS trial. Quantitative angiographic measurements of minimal lumen diameter and percent diameter stenosis were obtained within the treated segment, within the stent, and within its 5-mm proximal and distal edges. Patients treated with SESs had lower rates of binary (>50% diameter stenosis) angiographic restenosis within the segment (8.9% versus 36.3% with the BMS; P <0.001) and within the stent (3.2% versus 35.4% with the BMS; P <0.001). SESs were associated with significantly less late lumen loss within the treated segment, within the stent, and within its 5-mm proximal and distal edges (all P <0.001). The reduction of restenosis with the SES was consistent in patients at risk for restenosis, including those with small vessels, long lesions, and diabetes mellitus. The frequency of late aneurysms was similar in the 2 groups. Conclusions— Compared with BMSs, SESs reduced angiographic late lumen loss within the stent and its adjacent 5-mm margins in patients with complex native-vessel lesions.

The objectives of this study were to determine the effectiveness of a novel, trypsinized density gradient treatment designed to remove viruses from semen and to evaluate sperm viability after treatment. Exp. 1: Cryopreserved human semen (n = 6 donors) was layered on 2-mL columns of 45% Isolate (Irvine Scientific, Santa Ana, CA, USA) with or without 0.25% trypsin (trypsin-exposed and control, respectively), which overlaid 2-mL columns of 90% Isolate with or without 10 µg/mL soy-based trypsin inactivator (Sigma, St. Louis, MO, USA) and centrifuged (700g for 30 min). The layering of multiple density gradients is facilitated by a novel polypropylene tube insert, which also prevents contamination when extracting treated sperm (USA and international patents pending). Pellets were washed and then incubated at room temperature. Sperm were examined (motility and supravital staining) at 0, 2, 24, and 48 h post-treatment and the results evaluated using Wilcoxon Signed Rank and Rank Sum tests. Exp. 2: A cytopathic cell (MT-2) assay was conducted (6 replicates) to determine the effect of trypsin (1-min exposure) on HIV-1 RNA infectivity. Viral replication was assessed by syncytium formation and p24 antigen production. Exp. 3: Two pools of fresh human semen (N1 = 3 and N2 = 8 donors) were inoculated (1:1) with 1 × 108 copies/mL of cultured HIV-1 RNA, and one pool (N2) was inoculated (1:1) with plasma collected from patients infected with either Hepatitis B DNA (HBV) or C (HCV) RNA viruses; spiked and non-spiked aliquots were processed as in Exp. 1. Treated sperm pellets were analyzed for HIV-1 or HBV and HCV concentrations by the Bayer Versant branched DNA (bDNA; version 3.0) and/or the Roche Amplicor quantitative RT-PCR (1.5 ultrasensitive) assays at Toga Laboratories (Pty), Ltd. (Edenvale, South Africa). As a result of Exp. 1, there was significantly (P &lt; 0.05) lower motility (but not supravital staining) between trypsin-treated and control sperm at 0 h (58.0 vs. 69.3%) and 2 h (54.7 vs. 62.9%) post-washing; however, no differences were noted after 24 h (P &gt; 0.05). In Exp. 2, trypsin exposure affected HIV-1 RNA infectivity negatively as compared to controls in terms of MT-2 cell syncytium formation and p24 antigen production. Results of the bDNA and/or RT-PCR assays in Exp. 3 indicated that the procedure effectively reduced HIV-1, HBV, and HCV viral copies in the spiked semen samples to undetectable levels or levels below clinical relevance. In conclusion, the novel trypsin density gradient procedure was effective for removing HIV-1, HBV and HCV from spiked semen without markedly affecting sperm survival. Extrapolation of these results to natural infections may be unfounded for viruses (e.g. HBV) that are thought to integrate into sperm chromatin.

AbstractFocal nodular hyperplasia (FNH) and hepatocellular adenoma (HA) are uncommon benign hepatic tumors that continue to pose diagnostic and therapeutic challenges. An update of a recent Mayo Clinic experience is presented to highlight the management of patients harboring these neoplasms. A marked female predominance was seen. Incidental diagnosis was more prevalent with FNH, whereas symptomatic presentation was typical of HA. The frequency of oral contraceptive steroid use was similar regardless of tumor histology. Preoperative diagnosis remains difficult. Scintigraphy proved most specific, and ultrasonography and computed tomography were equally sensitive. Resection was employed in most patients. There was no mortality and minimal morbidity. Selective observation of FNH was uneventful, but resolution of HA after abstinence of oral contraceptive steroids was uncommon. These findings and data from the literature support selective management of benign liver tumors.