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Background: Studies analyzing optimal voltage thresholds for scar detection with electroanatomic mapping frequently lack a gold standard for comparison.Objective: The purpose of this study was to use a porcine infarct model with ex vivo magnetic resonance imaging (MRI) integration to characterize the relationship between interelectrode spacing and bipolar voltage thresholds and examine the influence of 3-dimensional scar on unipolar voltages.Methods: Thirty-two combined endocardial-epicardial electroanatomic maps were created in 8 postinfarct porcine subjects (bipolar 2-mm, 5-mm, and 8-mm interelectrode spacing and unipolar) for comparison with ex vivo MRI. Two thresholds were compared: (1) 95% normal distribution and (2) best fit to MRI. Direct electrogram analysis was performed in regions across from MRI-defined scar and adjacent to scar border zone.Results: A linear increase in optimal thresholds was observed with wider bipole spacing. The 95% thresholds for scar were lower than MRI-matched thresholds with moderate sensitivity for nontransmural scar (54% endo, 63% epi). Unipolar endocardial scar area exceeded MRI-defined scar, resulting in mismatched false scar in 5 of 8 (63%). Endocardial and epicardial unipolar voltages were lower than normal in regions adjacent and across from scar.Conclusion: Variations in interelectrode spacing necessitate tailored bipolar voltage thresholds to optimize scar detection. Statistical 95% thresholds appear to be conservative and not fully sensitive for the detection of scar defined by high-resolution ex vivo MRI. In the presence of endocardial scar, unipolar mapping to quantitatively characterize epicardial scar may be overly sensitive due to 3-dimensional spatial averaging. [ABSTRACT FROM AUTHOR]

Abstract: Metabolic measurements and screening of Trichoderma reesei have conventionally been performed during the hyphal stage of fungal development. To determine if flow cytometric measurements of protein expression could be made on germinating spores we created a gene construct, placing the Renilla reniformis green fluorescent protein gene under control of the cellobiohydrolase I (cbh1) promoter and terminator of T. reesei. This vector was transformed into T. reesei and GFP expression was measured in germlings by flow cytometry. Fluorescence associated with GFP expression was observed in germlings grown under conditions known to induce cellulases in Trichoderma. Spores were mutated using UV light and germinating spores were screened for increased GFP expression using high-speed cell sorting, to select for strains with genetic changes associated with increased protein expression. Secondary screens for cellulase production were conducted in microtitre plates. Flow cytometric screening of germinating spores expressing GFP yielded a mutant with improved ability to hydrolyse biomass. [ABSTRACT FROM AUTHOR]

Background: In performing catheter ablation of paroxysmal atrial fibrillation (PAF), the advent of electroanatomical mapping (EAM) has significantly reduced fluoroscopy time. Recent advances in the ability of EAM systems to simultaneously visualize multiple catheters have allowed some operators to perform certain procedures, such as catheter ablation of supraventricular tachycardias, with zero fluoroscopy use. Objective: The purpose of this study was to evaluate the feasibility and safety of pulmonary vein (PV) isolation with zero fluoroscopy use, using a combination of three-dimensional EAM and intracardiac echocardiography (ICE). Methods: Using the NavX EAM system, the right atrial (RA) and coronary sinus (CS) geometries were created without fluoroscopy. Fluoroless transseptal puncture was performed under ICE guidance. Using a deflectable sheath and a multipolar catheter, the left atrial (LA) and PV anatomies were rendered and, in select cases, integrated with a three-dimensional computed tomography (CT) image. Irrigated radiofrequency ablation was performed to encircle each pair of ipsilateral PVs. Results: This series included 20 consecutive PAF patients. RA/CS mapping required 5.5 ± 2.6 minutes. In all patients, single (n = 18) or dual (n = 2) transseptal access was successfully achieved. The LA-PV anatomy was rendered using either a circular (14 patients) or penta-array (six patients) catheter in 22 ± 10 minutes; CT image integration was used in 11 patients. Using 49 ± 18 ablation lesions/patient, electrical isolation was achieved in 38/39 ipsilateral PV isolating lesion sets (97%). The procedure time was 244 ± 75 minutes. There were no complications. Conclusion: Completely fluoroless catheter ablation of paroxysmal AF is safely feasible using a combination of ICE and EAM. [ABSTRACT FROM AUTHOR]

Abstract: The use of a computer navigation system is intended to optimize implant positioning. This study compares prospectively followed total knee arthroplasty (TKA) done with imageless computer-assisted navigation with a cohort of TKA done with manual instruments. Primary TKAs were performed on 147 knees, with 78 in the manual group and 69 in the navigated group. Coronal alignment was determined by postoperative full-length standing radiographs. The 2 groups had similar mean values for radiographic mechanical axis at 0.4°. There was a larger variation in alignment in the manual group, with 58% of the manual group within 2° of neutral compared with 78% of the navigated group (P = .008). The navigation system reproducibly resulted in a more reliable reproduction of the mechanical axis. [Copyright &y& Elsevier]

To study the effect of residual microscopic resection line disease in gastric cancer, we compared 47 patients with positive margins to 572 patients who underwent RO resections using a multivariate analysis of factors affecting outcome. Although the presence of positive margins was a significant and independent predictor of outcome for the entire group (N = 619), this factor lost significance in patients who had undergone D2 or D3 lymph node dissections (N = 466). Subset analysis within the D2/D3 group determined that this finding was limited mainly to those patients with >5 positive nodes (N = 189). The survival of patients who had ≤5 positive nodes (N = 277) was significantly worsened by a microscopically involved margin. Supporting this observation, intraoperative reexcision of microscopic disease based on frozen section analysis resulted in a significant improvement in overall survival in patients with ≤5 positive nodes but not in those with >5 positive nodes. We conclude that the significance of a positive microscopic margin in gastric cancer is dependent on the extent of disease. This factor is not predictive of outcome in patients who have undergone complete gross resection and have pathologically proved advanced nodal disease. Thus the goal in these cases should be an RO resection when feasible but with the realization that the presence of ≥5 positive nodes (N2 disease according to the 1997 American Joint Committee on Cancer criteria) will mainly determine outcome and not microscopic residual cancer at the margin. [ABSTRACT FROM AUTHOR]

Abstract: A 61-year-old woman presented with left upper quadrant/flank pain and increasing abdominal girth. CT scan showed a large complex, multi-cystic lesion in the left abdomen. Laparotomy revealed a large retroperitoneal mass attached to the left kidney. Left nephrectomy was performed and pathology demonstrated a benign cystic nephroma. Surgical oncologists should be aware of this rare renal lesion as the clinical and radiographic presentation may mimic other intra-abdominal cystic lesions. [Copyright &y& Elsevier]

The rare memory B cells in thymus (Thy) are considered the cells of origin for primary mediastinal large B-cell lymphoma. The objectives of the present study were to characterize the normal memory B-cell compartment in Thy and to support its association with primary mediastinal B-cell lymphoma. Seven paired human tissue samples from Thy and sternum bone marrow (BM) were harvested during cardiac surgery. B-cell subsets were phenotyped by Euroflow standard and fluorescence-activated cell sorting for microarray analysis on the Human Exon 1.0 ST Arrays platform. Differentially expressed genes between Thy and BM memory B cells were identified and correlated with the molecular subclasses of diffuse large B-cell lymphoma. Within Thy, 4% (median; range 2%–14%) of the CD45 + hematopoietic cells were CD19 + B cells, with a major fraction being CD27 + /CD38 – memory B cells (median 80%, range 76%–93%). The BM contained 14% (median; range 3%–27%), of which only a minor fraction (median 5%, range 2%–10%) were memory B cells. Global gene expression analysis of the memory B-cell subsets from the two compartments identified 133 genes upregulated in Thy, including AICDA, REL, STAT1, TNF family, SLAMF1, CD80, and CD86. In addition, exons 4 and 5 in the 3′ end of AICDA were more highly expressed in Thy than in BM. The Thy memory B-cell gene profile was overexpressed in primary mediastinal B-cell lymphoma compared with other diffuse large B-cell lymphoma subclasses. The present study describes a Thy memory B-cell subset and its gene profile correlated with primary mediastinal B-cell lymphomas, suggesting origin from Thy memory B cells. [ABSTRACT FROM AUTHOR]

Clear cell carcinoma originating in the abdominal wall is rare and usually develops within endometriotic implants in the scar. We describe 2 patients: a 42 year old with a 15 cm mass on the abdominal wall treated with neoadjuvant chemotherapy and excision and a 51 year old with a 6 cm abdominal mass treated with excision and adjuvant radiotherapy. [ABSTRACT FROM AUTHOR]

For decades, the enzymes of the fungus Hypocrea jecorina have served as a model system for the breakdown of cellulose. Three-dimensional structures for almost all H. jecorina cellulose- degrading enzymes are available, except for HjLPMO9A, belonging to the AA9 family of lytic polysaccharide monooxygenases (LPMOs). These enzymes enhance the hydrolytic activity of cellulases and are essential for cost-efficient conversion of lignocellulosic biomass. Here, using structural and spectroscopic analyses, we found that native HjLPMO9A contains a catalytic domain and a family-1 carbohydrate-binding module (CBM1) connected via a linker sequence. A C terminally truncated variant of HjLPMO9A containing 21 residues of the predicted linker was expressed at levels sufficient for analysis. Here, using structural, spectroscopic, and biochemical analyses, we found that this truncated variant exhibited reduced binding to and activity on cellulose compared with the full-length enzyme. Importantly, a 0.95-Å resolution X-ray structure of truncated HjLPMO9Arevealed that the linker forms an integral part of the catalytic domain structure, covering a hydrophobic patch on the catalytic AA9 module. We noted that the oxidized catalytic center contains a Cu(II) coordinated by two His ligands, one of which has a His-brace in which the His-1 terminal amine group also coordinates to a copper. The final equatorial position of the Cu(II) is occupied by a water-derived ligand. The spectroscopic characteristics of the truncated variant were not measurably different from those of full-length HjLPMO9A, indicating that the presence of the CBM1 module increases the affinity of HjLPMO9A for cellulose binding, but does not affect the active site. [ABSTRACT FROM AUTHOR]

Abstract: We have measured and of carbon-doped MgB2 under hydrostatic pressures up to 15.6 kbar. is determined to be −0.20  K/kbar and decreases with pressure at a rate that is consistent with the theoretical value for pure MgB2, . By analyzing our results within the theoretical framework of a dirty two-gap supersonductor, we determine values for the interband coupling and the ratio between the diffusivities associated with the two bands at three different pressures. We also extract the diffusivities and coherence lengths associated with each band. Finally, we estimate the pressure dependence of the charge carrier concentration in the band to be . [Copyright &y& Elsevier]

Reliable safe water supply is a pillar of society and a key to public health. The Nordic countries have an abundance of clean fresh water as a source for drinking water supplies. They have followed developments in safeguarding water, both the recommendations of the World Health Organization framework for safe drinking water and European legislation. Worldwide, including the Nordic countries, small water supplies are less compliant with water safety regulation. The forthcoming EU directive on drinking water require risk-based approaches and improved transparency on water quality. This research looks at the Nordic frameworks for safe water supply, with emphasis on risk-based approaches and smaller systems. We analyzed the legal frameworks for safe water, the structure of the water sector across the Nordic countries and explored how prepared these countries are to meet these requirements. Our findings show that, while legal requirements are mostly in place, delivery of information to the public needs to be improved. Most Nordic countries are in the process of implementing risk-based management in large and medium size water supplies, whereas small supplies are lagging. We conclude that a key to success is increased training and support for small supplies. We suggest wider adoption of the Nordic model of cooperation with benchmarking of safe water for all to transfer knowledge between the countries. This work provides insights into challenges and opportunities for the Nordic countries and provides insights relevant to countries worldwide in their effort towards realization of SDG Target 6.1. [ABSTRACT FROM AUTHOR]