Search

We report the case of a 4-year-old female infant who developed ongoing deep dermal necrosis of the bilateral legs after jellyfish contact in Thailand. Stepwise radical debridement and vacuum assisted wound therapy seemed to be an effective strategy to prevent progressive soft tissue loss.

During competition, kayak athletes must optimally adapt to environmental factors (e.g. wind, waves) to achieve peak performance. However, the ability to adapt to such perturbations has never been assessed in kayak paddling. Therefore, the aim of the current study was to evaluate the local dynamic stability in sports technique of youth sprint kayak athletes. In a cross-sectional study, 14 healthy male athletes were recruited from an elite youth sprint kayak squad. During an incremental kayak ergometer test, mean power, heart rates and local dynamic technique stability of hands, arms, trunk and paddle were registered and the association with the athletes 2000 m free-water times were estimated using mixed models. The 2000 m free-water performance significantly predicted the paddles (p = .037) local dynamic stability whereas no association was found for the trunk or the upper extremity kinematics. In conclusion, kayak athletes with high-performance capability over 2000 m paddling depict high local dynamic technique stability. This emphasizes the importance of a stable technique for advanced kayak skills, especially regarding paddling movements.

Background: Spaced learning has been shown to be effective in various areas like traditional knowledge or motor skill acquisition. To evaluate the impact of implementation of the spaced learning concept in laparoscopic training was the aim of this study., Methods: To evaluate the effectiveness of spaced learning, subjects were asked to perform four surgeon's square knots on a bowel model prior and post 3 h of hands-on training. All subjects were medical students and novice in laparoscopic suturing. Total time, knot stability (evaluated via tensiometer), suture accuracy, knot quality (Muresan score), and laparoscopic performance (Munz checklist) were assessed. Moreover, motivation was accessed using Questionnaire on Current Motivation., Results: Twenty students were included in the study; after simple randomization, ten were trained using "spaced learning" concept and ten conservatively. Both groups had comparable baseline characteristics and improved after training significantly regarding all aspects assessed in this study. Subjects that trained via spaced learning were superior in terms of suture performance, knot quality, and suture strength. Ultimately, spaced learning significantly decreased anxiety and impression of challenge compared to controls., Conclusion: The spaced learning concept is very suitable for complex motor skill acquisition like laparoscopic suturing and knot tying. It significantly improves laparoscopic performance and knot quality as shown by the knot score and suture strength. Thus, we recommend to incorporate spaced learning into training courses and surgical programs.

In 2009, the passing of the Family Smoking Prevention and Tobacco Control Act facilitated the establishment of the FDA Center for Tobacco Products (CTP), and gave it regulatory authority over the marketing, manufacture and distribution of tobacco products, including those termed 'modified risk'. On 4-6 April 2016, the Institute for In Vitro Sciences, Inc. (IIVS) convened a workshop conference entitled, In Vitro Exposure Systems and Dosimetry Assessment Tools for Inhaled Tobacco Products, to bring together stakeholders representing regulatory agencies, academia and industry to address the research priorities articulated by the FDA CTP. Specific topics were covered to assess the status of current in vitro smoke and aerosol/vapour exposure systems, as well as the various approaches and challenges to quantifying the complex exposures in in vitro pulmonary models developed for evaluating adverse pulmonary events resulting from tobacco product exposures. The four core topics covered were: a) Tobacco Smoke and E-Cigarette Aerosols; b) Air-Liquid Interface-In Vitro Exposure Systems; c) Dosimetry Approaches for Particles and Vapours/In Vitro Dosimetry Determinations; and d) Exposure Microenvironment/Physiology of Cells. The 2.5-day workshop included presentations from 20 expert speakers, poster sessions, networking discussions, and breakout sessions which identified key findings and provided recommendations to advance these technologies. Here, we will report on the proceedings, recommendations, and outcome of the April 2016 technical workshop, including paths forward for developing and validating non-animal test methods for tobacco product smoke and next generation tobacco product aerosol/vapour exposures. With the recent FDA publication of the final deeming rule for the governance of tobacco products, there is an unprecedented necessity to evaluate a very large number of tobacco-based products and ingredients. The questionable relevance, high cost, and ethical considerations for the use of in vivo testing methods highlight the necessity of robust in vitro approaches to elucidate tobacco-based exposures and how they may lead to pulmonary diseases that contribute to lung exposure-induced mortality worldwide., (2017 FRAME.)

Exposure to air pollution resulting from fossil fuel combustion has been linked to multiple short-term and long term health effects. In a previous study, exposure of lung epithelial cells to engine exhaust from heavy fuel oil (HFO) and diesel fuel (DF), two of the main fuels used in marine engines, led to an increased regulation of several pathways associated with adverse cellular effects, including pro-inflammatory pathways. In addition, DF exhaust exposure was shown to have a wider response on multiple cellular regulatory levels compared to HFO emissions, suggesting a potentially higher toxicity of DF emissions over HFO. In order to further understand these effects, as well as to validate these findings in another cell line, we investigated macrophages under the same conditions as a more inflammation-relevant model. An air-liquid interface aerosol exposure system was used to provide a more biologically relevant exposure system compared to submerged experiments, with cells exposed to either the complete aerosol (particle and gas phase), or the gas phase only (with particles filtered out). Data from cytotoxicity assays were integrated with metabolomics and proteomics analyses, including stable isotope-assisted metabolomics, in order to uncover pathways affected by combustion aerosol exposure in macrophages. Through this approach, we determined differing phenotypic effects associated with the different components of aerosol. The particle phase of diluted combustion aerosols was found to induce increased cell death in macrophages, while the gas phase was found more to affect the metabolic profile. In particular, a higher cytotoxicity of DF aerosol emission was observed in relation to the HFO aerosol. Furthermore, macrophage exposure to the gas phase of HFO leads to an induction of a pro-inflammatory metabolic and proteomic phenotype. These results validate the effects found in lung epithelial cells, confirming the role of inflammation and cellular stress in the response to combustion aerosols.

Background: Ship engine emissions are important with regard to lung and cardiovascular diseases especially in coastal regions worldwide. Known cellular responses to combustion particles include oxidative stress and inflammatory signalling., Objectives: To provide a molecular link between the chemical and physical characteristics of ship emission particles and the cellular responses they elicit and to identify potentially harmful fractions in shipping emission aerosols., Methods: Through an air-liquid interface exposure system, we exposed human lung cells under realistic in vitro conditions to exhaust fumes from a ship engine running on either common heavy fuel oil (HFO) or cleaner-burning diesel fuel (DF). Advanced chemical analyses of the exhaust aerosols were combined with transcriptional, proteomic and metabolomic profiling including isotope labelling methods to characterise the lung cell responses., Results: The HFO emissions contained high concentrations of toxic compounds such as metals and polycyclic aromatic hydrocarbon, and were higher in particle mass. These compounds were lower in DF emissions, which in turn had higher concentrations of elemental carbon ("soot"). Common cellular reactions included cellular stress responses and endocytosis. Reactions to HFO emissions were dominated by oxidative stress and inflammatory responses, whereas DF emissions induced generally a broader biological response than HFO emissions and affected essential cellular pathways such as energy metabolism, protein synthesis, and chromatin modification., Conclusions: Despite a lower content of known toxic compounds, combustion particles from the clean shipping fuel DF influenced several essential pathways of lung cell metabolism more strongly than particles from the unrefined fuel HFO. This might be attributable to a higher soot content in DF. Thus the role of diesel soot, which is a known carcinogen in acute air pollution-induced health effects should be further investigated. For the use of HFO and DF we recommend a reduction of carbonaceous soot in the ship emissions by implementation of filtration devices.

Background: Prospective data of transumbilically laparoscopic-assisted appendectomies (TULAA) is absent in the pediatric population. We therefore compared the midterm outcome of TULAA with open (OA) and laparoscopic (LA) appendectomies in children with appendicitis in a matched prospective study., Methods: A total of 20 patients operated with TULAA were matched to 20 cases operated by LA and OA, respectively, according to sex, age, and histology of the resected appendix. All 60 children were evaluated during a 3-month follow-up visit., Results: The subjective pain level after discharge, the rate of complications, and persistent painful wound as well as the duration of days refraining from school or kindergarten were similar in all three groups. The wound satisfaction was significantly higher in TULAA and LA. Children operated with TULAA had a faster return to full physical activity compared with OA., Conclusion: Our data suggest that TULAA, LA, and OA have a similar outcome 3 months after surgery apart from cosmetic appearance of the wound and return to full physical activity in pediatric patients. Whether parental bias or the increased wound satisfaction act as confounders for early return to full physical activity should be evaluated in larger prospective randomized trials., (Georg Thieme Verlag KG Stuttgart · New York.)

In this paper we describe a new approach to quantify the stability and coalescence kinetics of thermally switchable emulsions using an imaging-based microcentrifugation method. We first show that combining synchronized high-speed imaging with microfluidic centrifugation allows the direct measurement of the thermodynamic stability of emulsions, as expressed by the critical disjoining pressure. We apply this to a thermoresponsive emulsion, allowing us to measure the critical disjoining pressure as a function of temperature. The same method, combined with quantitative image analysis, also gives access to droplet-scale details of the coalescence process. We illustrate this by measuring temperature-dependent coalescence rates and by analysing the temperature-induced switching between two distinct microscopic mechanisms by which dense emulsions can destabilise to form a homogeneous oil phase.

Background: The pathogenesis of intestinal dysmotility in gastroschisis is not completely understood. Peel formation and disorganization of interstitial Cajal cells (ICC) have been proposed in humans. The aim of this study was to evaluate the impact of prenatal coverage of gastroschisis on gut inflammation and expression of ICC in a fetal lamb model., Methods: Twenty-one German blackhead sheep with an abdominal wall defect that was created fetoscopically on day 77 of 145 days gestation were used in this study. Intrauterine surgery with the aim to cover the defect was performed 3 weeks later; two fetuses were covered completely, 5 partially and 11 remained uncovered. Three fetuses without gastroschisis were used as controls. All fetuses were retrieved by cesarean section at day 135. Samples of the small intestine were stained with hematoxylin and eosin for histologic analysis of peel formation and serosal and muscular thickness. For ICC detection, immunohistochemistry using anti-CD117 (c-Kit) antibody was used., Results: In all samples with exposure to amniotic fluid, peel formation and significantly decreased ICC were found. Complete coverage reduced peel formation and disorganization of ICC compared to uncovered animals almost to the level of controls., Conclusions: Peel formation and ICC derangement were significantly reduced by prenatal coverage of gastroschisis. Moreover, this animal model mimics the histopathological bowel changes as seen in human gastroschisis and may, therefore, be used for further research on the pathophysiology and fetal therapy of this malformation.

Objective: To test the clinical and sonographic predictors of testicular torsion (TT) with the aim of reducing negative exploration rates., Patients and Methods: We performed a prospective study of all boys treated for 'acute scrotum' at our institute between January 2001 and April 2012 and clinical findings were documented. If available, ultrasonography (US) was added to the diagnostic evaluation. A prediction of the diagnosis was based on clinical and sonographic features, and was followed by surgical exploration in all patients., Results: A total of 104 patients were included in the 16-month period of the study. No single finding excluded TT. The clinical features (pain <24 h, nausea/vomiting, abnormal cremasteric reflex, high position of the testis) appeared predictive (100% sensitivity) and the clinical scoring system was proven to be reliable, reducing the negative exploration rate by >55%. Ultrasound predictors alone were not able to identify all boys with TT., Conclusions: It is safe to refrain from routine surgical exploration in every child with acute scrotum if the clinical score is applied, which results in a marked reduction of negative explorations. A reliable diagnosis could not be obtained based on US alone. As scrotal US is unpleasant for the child, we propose to refrain from this if the clinical score is positive. Patients with a negative clinical score are suitable candidates for US to establish and secure diagnosis., (© 2013 The Authors. BJU International © 2013 BJU International.)

Introduction: The embryogenesis of gastroschisis is not completely understood. The aim of our study was to evaluate the impact of a simple abdominal wall defect versus a defect including eviscerated intestine or omentum for the development of gastroschisis in a fetal lamb model., Material and Methods: At mid-gestation (day 77) an abdominal wall defect was fetoscopically created with three different approaches in 19 German blackhead sheep. The intestine was eviscerated in 7 fetuses (group 1). The peritoneum was incised and a patch of the omentum pulled through the incision in 5 fetuses (group 2). In 7 fetuses (group 3) the skin and rectus muscle were incised until the peritoneum was visible. In this group, no abdominal contents were exteriorized and the peritoneum was left intact. A second fetoscopic procedure was performed 21 days later, assessing the condition and extension of eviscerated bowel. The fetus was retrieved by Cesarean section on day 132 and evaluated., Results: The second fetoscopy acting as a control for the creation of gastroschisis demonstrated eviscerated and inflamed intestine in all 3 groups. The amount of eviscerated intestine did not appear to depend on the size of the defect nor on its duration., Discussion: It appears that a simple incision of the abdominal wall with intact peritoneum is sufficient for the development of gastroschisis in a fetal sheep model. This finding may improve the understanding of the etiology of gastroschisis., (Copyright © 2012 S. Karger AG, Basel.)

Background: Gastroschisis is a malformation consisting of an abdominal wall defect with eviscerated bowel. Its standard treatment is postnatal repositioning or temporary prosthetic bag placement. The aim of our study is to evaluate the feasibility of its fetoscopic management in a lamb model., Methods: At mid-gestation (day 75), gastroschisis was created in eight German blackhead sheep. A second fetoscopic procedure was performed on day 105, assessing the viability, extension, and potential for repositioning of eviscerated bowel. The fetus was retrieved by Cesarean section on day 132 and evaluated., Results: In six fetuses gastroschisis could be successfully created and assessed with fetoscopy. Two fetuses were lost due to technical complications. Primary repair by repositioning the intestine into the abdomen was not possible because it grew into an inflammatory conglomerate too large for the small fetal abdominal cavity., Conclusions: Although technically demanding, we were able to produce and reassess six cases of gastroschisis by fetoscopy. As primary repositioning appears unfavorable, fetoscopic prosthetic bag placement may become an alternative.

We present the results of experiments studying droplet coalescence in a dense layer of emulsion droplets using microfluidic circuits. The microfluidic structure allows direct observation of collisions and coalescence events between oil droplets dispersed in water. The coalescence rate of a flowing hexadecane-in-water emulsion was measured as a function of the droplet velocity and droplet concentration from image sequences measured with a high-speed camera. A trajectory analysis of colliding droplet pairs allows evaluation of the film drainage profile and coalescence time t(c.) The coalescence times obtained for thousands of droplet pairs enable us to calculate coalescence time distributions for each set of experimental parameters, which are the mean droplet approach velocity (v(0)), the mean dispersed phase fraction (φ) and the mean hydraulic diameter of a droplet pair (d(p)). The expected value E(t(c)) of the coalescence time distributions scales as E(t(c)) is proportional to (v(0))(-0.105±0.043)(d(p))(0.562±0.287), but is independent of φ. We discuss the potential of the procedure for the prediction of emulsion stability in industrial applications.

The acidic oxide SO₂ and protic acid HCl are among the gases released in the combustion of coal and the incineration of municipal waste. They are typically removed by wet or dry scrubbing involving calcium carbonate or calcium hydroxide. The molten alkali carbonate eutectic provides a liquid-state alternative that readily absorbs SO₂ and HCl and does not become covered with a passivating layer. Gas-liquid scattering experiments utilizing the eutectic mixture (44 mol % Li₂CO₃, 31 mol % Na₂CO₃, 25 mol % K₂CO₃) reveal that the reaction probability for HCl(g) + CO₃²⁻ → CO₂(g) + OH⁻ + Cl⁻ is 0.31 ± 0.02 at 683 K and rises to 0.39 at 783 K. Gaseous CO₂ is formed within 10⁻⁴ s or less, implying that the reaction takes place in a liquid depth of less than 1000 Å. When the melt is exposed to D₂O, the analogous reaction D₂O(g) + CO₃²⁻ → CO₂(g) + 2OD⁻ occurs too slowly to measure and no water uptake is observed. Together with previous studies of SO₂(g) + CO₃²⁻ → CO₂(g) + SO₃²⁻, these results demonstrate that molten carbonates efficiently remove both gaseous HCl and SO₂ while reacting at most weakly with water vapor. The experiments further highlight the remarkable ability of hot CO₃²⁻ ions to behave as a base in reactions with protic and Lewis acids.

Molecular beam scattering experiments are used to investigate reactions of SO(2) at the surface of a molten alkali carbonate eutectic at 683 K. We find that two-thirds of the SO(2) molecules that thermalize at the surface of the melt are converted to gaseous CO(2) via the reaction SO(2)(g) + CO(3)(2-) --> CO(2)(g) + SO(3)(-2). The CO(2) product is formed from SO(2) in less than 10(-6) s, implying that the reaction takes place in a shallow liquid region less than 100 A deep. The reaction probability does not vary between 683 and 883 K, further implying a compensation between decreasing SO(2) residence time in the near-interfacial region and increasing reactivity at higher temperatures. These results demonstrate the remarkable efficiency of SO(2) --> CO(2) conversion by molten carbonates, which appear to be much more reactive than dry calcium carbonate or wet slurries commonly used for flue gas desulfurization in coal-burning power plants.

Phospholipids are a main component of cell membranes. Therefore, the experimental investigation of the self-organization of phospholipids is of great interest. Here we present results concerning the orientation of the phospholipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) at the surface of the polar solvents formamide and 3-hydroxypropionitrile (HPN), which we investigated by means of neutral impact collision ion scattering spectroscopy. It is shown that, in HPN, at low POPC surface excesses, the phospholipids are oriented with the polar headgroups pointing out of the solution. It is concluded that the behavior of lipids at the surface of liquids is more complex than expected and to a great extent dependent on the solvent. Comprehension of the behavior of POPC in the applied solvents might contribute to the understanding of the self-organization of phospholipids in water.

The aim of the current study was to investigate the role of promoter methylation of adenomatous polyposis coli (APC) and epithelial cadherin (E-cadherin) genes in endometrial tumorigenesis. The methylation status of both genes was investigated in 43 cases of normal endometrium, 21 simple hyperplasia, 17 atypical hyperplasia, and 86 endometrial carcinoma (EC). Additionally, the methylation pattern of both genes was analyzed in 24 primary ECs and their corresponding metastases. DNA methylation of the APC gene increased from atypical hyperplasia (23.5%) to endometrial carcinoma, reaching its highest level of 77.4% in early stage cancer (FIGO I and II) and decreasing stepwise to 24.2% in advanced stage carcinomas (FIGO III and IV). No methylation of APC was found in normal endometrium or simple hyperplasia. Methylation of E-cadherin was found only in EC (22.1%). The mean age of the patients with aberrant APC methylation was 68.8 years and was significantly higher compared to the mean age (60.9 years) of the patients without methylation of APC promoter (P = 0.02). APC promoter methylation significantly correlated with decreased protein expression of APC (P = 0.039), with increased expression of the Ki-67 proliferative marker (P = 0.006) and decreased metastatic potential (P = 0.002). There was no correlation between APC and E-cadherin methylation patterns and the other clinicopathologic features, nor with patient outcome. Our results suggest that hypermethylation of APC promoter region is an early event in endometrial tumorigenesis.

Development of cardiac hypertrophy and progression to heart failure entails profound changes in myocardial metabolism, characterized by a switch from fatty acid utilization to glycolysis and lipid accumulation. We report that hypoxia-inducible factor (HIF)1alpha and PPARgamma, key mediators of glycolysis and lipid anabolism, respectively, are jointly upregulated in hypertrophic cardiomyopathy and cooperate to mediate key changes in cardiac metabolism. In response to pathologic stress, HIF1alpha activates glycolytic genes and PPARgamma, whose product, in turn, activates fatty acid uptake and glycerolipid biosynthesis genes. These changes result in increased glycolytic flux and glucose-to-lipid conversion via the glycerol-3-phosphate pathway, apoptosis, and contractile dysfunction. Ventricular deletion of Hif1alpha in mice prevents hypertrophy-induced PPARgamma activation, the consequent metabolic reprogramming, and contractile dysfunction. We propose a model in which activation of the HIF1alpha-PPARgamma axis by pathologic stress underlies key changes in cell metabolism that are characteristic of and contribute to common forms of heart disease.

Objective: The aim of this study was to investigate the role of p16 in tumorigenesis of endometrial carcinoma (EC)., Methods: Expression of p16 protein was analyzed using immunohistochemistry. The methylation status of p16 promoter region was determined by methylation-specific PCR. Deletion analysis of the p16 gene was performed by PCR-analyses., Results: Aberrant protein expression of p16 was observed in 18 of 46 (39.2%) ECs and correlated significantly with p16 alterations, including gene deletions in 26 of 46 (56.5%) ECs and promoter hypermethylation in 8 of 46 (17.4%) ECs (p<0.001). A significant increase in the frequency of p16 alterations from early stage (I-II) to advanced stage (III-IV) ECs was observed (p=0.002). There was no significant correlation between p16 protein expression and the clinico-pathological features of EC. The development of metastases correlated significantly with the frequency of p16 alterations: p16 alterations were detected in 14 of 15 (93.3%) PTs with metastases and in only 18 of 31 (58.1%) PTs without metastases (p=0.018). The genetic comparison of 15 primary ECs and their paired metastases revealed that in most of the cases the deleted region of p16 gene remains the same or becomes larger during the progression from primary tumor to its corresponding metastases., Conclusion: Our results suggest that p16 alterations and particularly p16 gene deletions in ECs are associated with increased incidence of metastases.

Unlabelled: To date, no effective adjuvant drug preventing the aggressive spread of tumour cells in late stages of cancer disease or at the time-point of primary tumour removal is available. Although proteases, including members of the large serine protease family, were shown to be promising targets for an anti-metastatic cancer therapy, synthetic protease inhibitors (SPIs) have so far failed to be introduced into the clinic. In addition to considerations in the design of classical in vivo -tests of SPIs as cancer therapy agents, we here review our findings with a straightforward, highly sensitive and very fast in vivo metastasis model and its implications in the development of efficient anti-metastatic SPIs. The lacZ-tagging of tumour cells of this very aggressive T-cell lymphoma model allowed highly sensitive and reproducible detection of metastases within seven days after tumour cell inoculation by X-gal staining of whole organs, allowing cost-effective and material-saving side-by-side screening of a series of SPIs with different specificities for different serine proteases. By establishment of specificity/antimetastatic efficacy correlations we identified coagulation factor Xa as one important target of anti-metastatic SPIs and could use this information for the subsequent design and optimization of factor Xa-specific lead structures., Conclusion: We exemplify the usefulness of high-throughput in vivo analysis to direct optimization of lead structures and how this may allow unexpected insight into the molecular biology of metastasis.

As-deposited films of multilayered polyelectrolytes are considered to be non-equilibrium structures. Due to the strong attraction between oppositely charged polyions, polyelectrolyte interdiffusion is thought to be suppressed during the adsorption process. Equilibration is promoted by a decrease of the electrostatic attraction between polyion pairs. We have used neutral impact collision ion scattering spectroscopy to investigate the influence of polyelectrolyte multilayer annealing in water and aqueous 1 M NaCl solutions at different temperatures (20 and 70 degrees C) on the increase in interpenetration of a single polyelectrolyte layer throughout the whole film. The multilayers were composed of poly(4-vinylpyridinium) and poly(4-styrenesulfonate). Contrast between neighboring layers was established by labelling the layer in question with the heavy atom ruthenium. It is found that both temperature and salt increase layer interpenetration, whereas salt has a stronger influence than temperature. From numerical simulations polyelectrolyte diffusion coefficients were evaluated for the different annealing conditions. The influence of temperature and salt on the equilibration of the film is interpreted in terms of increased screening of polyion charges and binding of small counterions to polyion monomeric units.

The chemical potential of a surfactant in solution can be calculated from the Gibbs adsorption equation when the surface excess of the surfactant and the surface tension of the solution as a function of surfactant concentration are known. We have investigated a solution of the nonionic surfactant 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) in the polar solvent 3-hydroxypropionitrile at concentrations below and above the critical micelle concentration (cmc). Neutral impact collision ion scattering spectroscopy was applied for the direct measurement of the surface excess of POPC as a function of concentration. The Gibbs adsorption equation was applied in conjunction with surface tension measurements to evaluate the chemical potential and the activity coefficients of POPC, respectively. We find that the solution shows ideal behavior up to the cmc and that the chemical potential remains constant at concentrations larger than the cmc.

Neutral impact collision ion scattering spectroscopy under normal incidence is known to yield the concentration depth profiles of all elements except hydrogen at the surface of liquids and other amorphous material. In the evaluation of the data one tactically has to assume that the top surface layer and the adjacent layers are laterally homogeneous. In the present paper we establish that the angular resolved mode of this spectroscopy is able to test with high accuracy whether the lateral homogeneity is valid and-if this is not the case-in which way the top layer is structured. In particular, it is possible to map out the local environment of selected atoms. We expect that this so far inaccessible information on the local topography at liquid surfaces will have an impact on the understanding of reactions at the gas/liquid interface.

Commonly, the surface excess is determined from surface tension measurements via the Gibbs equation. This equation relates the activity (chemical potential), the surface excess, and the surface tension. When knowing two out of the three quantities, the third one can be calculated. Unfortunately, in the case of surface active components the concentration is in most cases too low to determine the activity from a measurable change in the bulk properties and thus assumptions are made about the activity coefficients. However, if the surface excess is measured directly and the surface tension is known, the activity can be determined making use of the Gibbs equation. The surface excess is the quantity of a surfactant solution which changes most strongly with the concentration. Thus it is obvious that this procedure should be used to determine activity coefficients of surfactants. One of the few techniques for determining the surface excess directly is neutral impact collision ion scattering spectroscopy (NICISS). With NICISS concentration depth profiles can be measured in the surface near region with a depth resolution of a few angströms. The surface excess and the activities are investigated here for the system tetrabutylphosphonium bromide (Bu4PBr) dissolved in the polar solvent formamide.

MR imaging technology is continually evolving and improving. Endorectal MR imaging provides excellent anatomic detail and is the most accurate imaging modality for staging prostate cancer with the ability to affect therapy and cure in many men. Failure to detect microscopic disease and microscopic capsular invasion remain significant weaknesses. MR spectroscopy has great potential for improving the sensitivity and specificity of MR imaging and expanding its diagnostic and staging usefulness.

Objective: We evaluated whether the use of multiple window and level settings on a soft-copy workstation improves diagnostic accuracy on chest and abdominal CT. We hypothesized that routinely using window and level settings during soft-copy interpretation would beneficially affect the final diagnosis without compromising efficiency., Materials and Methods: Two hundred three randomly selected abdominal and chest CT scans were interpreted by three radiologists using a four-monitor soft-copy workstation (images per screen, nine; resolution, 2K). After the initial interpretations, all scans were reevaluated by the same radiologists using additional liver and bone window and level settings. Differences in conspicuity and characterization of abnormalities were graded on a three-point scale., Results: Conspicuity and characterization of abnormalities were improved in 67% of abnormal findings (81/121; p = 0.01). Improvement (a finding that substantially affected the final diagnosis) was present in 18% of abnormal findings (22/121; p = 0.04). On average, the evaluation of images at multiple window and level settings required an additional 40 sec per case., Conclusion: The use of multiple window and level settings during soft-copy interpretation resulted in improved lesion detectability and characterization with greater diagnostic efficacy. Using soft-copy workstations, radiologists can evaluate images using multiple settings without compromising efficiency.

Recent advances in MR imaging techniques and its multiplanar capability allow for improved detection and characterization of benign and malignant processes occurring in the thoracoabdominal region. It is important to the staging process of patients with known malignancy to correctly diagnose incidental masses in this region, including hepatic or adrenal lesions, which initially may be identified by other imaging modalities. MR imaging provides a complimentary role in lesion detection and diagnosis that may ultimately affect therapeutic management and outcome.

Objective: The purpose of this study was to describe the imaging features of posttransplant lymphoproliferative disorder (PTLD) in pancreas transplant recipients., Conclusion: The prominent image finding of PTLD in pancreas transplant recipients is diffuse allograft enlargement, an appearance that may be indistinguishable from the image findings of acute pancreatitis or transplant rejection. However, failure of response to immunosuppressive therapy, presence of intraallograft or extraallograft focal masses, or organomegaly may suggest the diagnosis of PTLD.

Objective: The purpose of our study was to assess the use of low-milliamperage CT fluoroscopy guidance for percutaneous abdominopelvic biopsy and therapeutic procedures., Materials and Methods: We reviewed the clinical records and relevant imaging studies of 97 patients who underwent 119 percutaneous CT fluoroscopy-guided abdominal or pelvic procedures: fluid collection aspiration or drainage catheter insertion (n = 59), biopsy (n = 49), hepatocellular carcinoma ethanol ablation (n = 6), chemoneurolysis (n = 4), and brachytherapy catheter insertion (n = 1). These procedures were guided using a helical CT scanner providing real-time fluoroscopy reconstruction at six frames per second. A control panel and video monitor beside the gantry allowed direct operator control during all interventional procedures., Results: One hundred twelve (94.1%) procedures were successfully performed using either a stand-off needle holder and continuous real-time CT fluoroscopy guidance or incremental manual insertion and intermittent CT fluoroscopy to confirm position. Image quality using low milliamperage was adequate for needle or drainage tube placement in all but two low-contrast liver lesions. Two hematomas were accessed but yielded no fluid on aspiration; one drainage procedure was abandoned after the patient developed endotoxic shock. Imaging of ethanol distribution during injection facilitated tumor ablation and neurolytic procedures. CT fluoroscopy allowed rapid assessment of needle, guidewire, dilator, and catheter placement, especially in nonaxial planes. Average CT fluoroscopy time for biopsy and therapeutic procedures was 133 sec (range, 35-336 sec) and 186 sec (range, 20-660 sec), respectively., Conclusion: CT fluoroscopy is a practical clinical tool that facilitates effective performance of percutaneous abdominal and pelvic interventional procedures.

Purpose: Traditionally, live renal donors are evaluated with excretory urography and renal arteriography. Helical computerized tomography (CT) arteriography offers a less invasive alternative for demonstrating necessary anatomical information before laparoscopic allograft harvest. We evaluate the accuracy of helical CT arteriography in depicting renal vascular anatomy with an emphasis on the detection of arterial and venous anomalies., Materials and Methods: Imaging studies were done on 175 patients according to a standard CT arteriography protocol with early arterial phase scanning (14 to 20-second delay), and 1 mm. axial and 3-dimensional maximum intensity projection reconstructions. Renal vascular anatomy was mapped with attention to aberrant arterial and venous anatomy. Intraoperative findings were correlated at laparoscopic donor nephrectomy., Results: There was overall agreement between CT arteriography and laparoscopic findings in 163 cases (93%). Supernumerary renal arteries were identified in 40 cases (23%). Sensitivity, specificity and accuracy of CT arteriography for arterial anatomy were 91, 98 and 96%, respectively. Cases with less than 2 mm. accessory arteries or early branching single vessels simulating dual arteries were misdiagnosed. Venous anomalies occurred in 11 patients (6.3%). Sensitivity, specificity and accuracy of CT arteriography for venous anatomy were 65, 100, and 97%, respectively. Misdiagnoses included early venous bifurcations and supernumerary tributary veins, which were poorly opacified., Conclusions: Helical CT is highly accurate and specific for the demonstration of renal arterial anatomy. Poor opacification resulted in a lower sensitivity for venous anatomy. Overall, helical CT provides essential anatomical information, and is an alternative to standard urography and arteriography.

The ubiquity of the world-wide web allows unique educational opportunities for continuing medical education (CME). We have designed a comprehensive breast imaging CME curriculum to permit individual physicians in their homes or offices to use personal computers to ease the burden of this process. Category 1 CME credits can be earned off-hours without having the physician travel out of town. In addition, since the course is computer-based, the overall costs to the participant are substantially reduced. The program can be updated on an ongoing basis to include new technology or to provide additional information requested by the users.

Purpose: To evaluate the use of dynamic contrast material-enhanced gradient-recalled-echo MR imaging for the diagnosis of acute pancreatic transplant rejection, as confirmed at histopathologic analysis., Materials and Methods: Thirty MR imaging studies were performed in 25 patients within 3 days of percutaneous biopsy or pancreatectomy. The mean percentage of parenchymal enhancement (MPPE) at dynamic contrast-enhanced MR imaging was calculated., Results: Biopsy findings were no evidence of rejection (n = 7 [23%]), mild rejection (n = 10 [33%]), moderate (n = 6 [20%]) and severe (n = 2 [7%]) acute rejection, and infarction (n = 5 [17%]). The corresponding MPPEs at 1 minute were 106%, 66%, 62%, 57%, and 3%, respectively. Overlap of cases in the normal and rejection groups occurred; however, using an MPPE cutoff of 100% resulted in a sensitivity of 96%. An MPPE over 120% was seen in the normal group only. The MPPE was significantly greater in the normal group than in the rejection or infarction group (P < .05)., Conclusion: Dynamic contrast-enhanced MR imaging is highly sensitive for the detection of acute pancreatic transplant rejection. Because of overlap of cases in the normal and rejection groups, percutaneous biopsy may be needed in some cases. Pancreatic allografts with infarction can be clearly identified.

Objective: Torsion of a renal transplant is a rare complication with nonspecific clinical manifestations. Prompt detection is necessary to allow surgical treatment and to preserve renal function. We describe the radiologic appearances of torsion of intraperitoneal renal transplants in patients who have undergone simultaneous renal and pancreatic transplantation or dual renal transplantation., Conclusion: Renal transplant torsion should be suspected when a change in renal axis associated with abnormal perfusion occurs in an intraperitoneal kidney.

The article discusses the importance of implementing a clinical pathway in the neonatal intensive care unit that emphasizes parent education. Through an extensive literature review, a clinical path was developed that incorporates parent education through an individualized, developmentally supportive model of interaction. The clinical path is designed to be utilized as a teaching tool from birth to discharge from the hospital. The path can serve as a guide for teaching and identifying learning objectives a long a time line as well as for providing consistent documentation.

A computerized radiology education teaching file application, MRW (Multimedia Radiology Workstation), was produced in our department as a collaboration of faculty, fellows and a doctoral student. This inexpensive and flexible system is novice-programmable and is capable of capturing images from multiple modalities (including still and cine image) and organizing them into individual electronic teaching cases. Help and tutorial functions support the main case display functions.

A pilot study was conducted to investigate the influence of electromagnetic fields in the short-wave range (3-30 MHz) radio transmitter signals on salivary melatonin concentration in dairy cattle. The hypothesis to be tested was whether EMF exposure would lower salivary melatonin concentrations, and whether removal of the EMF source would be followed by higher concentration levels. For this pilot study, a controlled intervention trial was designed. Two commercial dairy herds at two farms were compared, one located at a distance of 500 m (exposed), the other at a distance of 4,000 m (unexposed) from the transmitter. At each farm, five cows were monitored with respect to their salivary melatonin concentrations over a period of ten consecutive days. Saliva samples were collected at two-hour intervals during the dark phase of the night. As an additional intervention, the short-wave transmitter was switched off during three of the ten days (off phase). The samples were analyzed using a radioimmunoassay. The average nightly field strength readings were 21-fold greater on the exposed farm (1.59 mA/m) than on the control farm (0.076 mA/m). The mean values of the two initial nights did not show a statistically significant difference between exposed and unexposed cows. Therefore, a chronic melatonin reduction effect seemed unlikely. However, on the first night of re-exposure after the transmitter had been off for three days, the difference in salivary melatonin concentration between the two farms (3.89 pg/ml, CI: 2.04, 7.41) was statistically significant, indicating a two- to seven-fold increase of melatonin concentration. Thus, a delayed acute effect of EMF on melatonin concentration cannot completely be excluded. However, results should be interpreted with caution and further trials are required in order to confirm the results.

Objective: The objective of this study was to evaluate the ability of transrectal surface coil MR imaging to reveal local recurrence of malignancy in men who have had radical prostatectomy for prostatic adenocarcinoma., Subjects and Methods: We performed prospective analysis of 41 men who had undergone radical prostatectomy (range of time since surgery, 8 months to 5 years; mean, 26 months), 35 of whom had clinical suspicion of recurrent prostatic cancer and the remaining six of whom had no clinical evidence of recurrent prostatic cancer (controls). Our imaging used a transrectal surface coil on a 1.5-T MR scanner. Sagittal and axial fat-saturated T2-weighted fast spin-echo as well as axial T1-weighted unenhanced and gadolinium-enhanced MR images of the prostatic bed were acquired in all patients. Thirty-one of the 35 men with clinical suspicion of recurrent prostatic cancer had elevated prostate-specific antigen (PSA) levels (> or = 0.4 ng/ml), and 22 of these 31 men had a palpable prostatic bed module or induration. The four of 35 men with clinical suspicion of recurrent prostatic cancer who had PSA levels less than 0.4 ng/ml had a palpable prostatic bed nodule or induration. Transrectal biopsy of the prostatic bed was directed by digital palpation or transrectal sonography in all 35 men with clinical suspicion of recurrent malignancy., Results: Thirty-one of the 35 men who had clinical suspicion of local recurrence of prostatic cancer had a soft-tissue nodule revealed in the prostatic bed by transrectal surface coil MR imaging. Compared with the adjacent muscle, all nodules were isointense on the T1-weighted images, hyperintense on the T2-weighted images, and enhanced with gadolinium administration. The 22 patients who had an abnormal MR scan and a palpable nodule or induration and the nine patients with elevated PSA levels, no palpable abnormality, and an abnormality revealed by MR imaging underwent transrectal biopsy; all had recurrent prostatic cancer proven by histology in the four patients with a palpable prostatic bed nodule or induration and normal PSA levels, MR imaging showed no distinct soft-tissue nodule or area of enhancement in the prostatic bed; transrectal biopsy of the palpable nodule or induration yielded fibrosis but no malignancy in all four patients. In the six control patients with no clinical evidence of local recurrence, MR imaging revealed no evidence of recurrent malignancy; all six control patients continue to have no clinical evidence of recurrent prostatic cancer with a minimum follow-up of 22 months. Thus, the sensitivity of MR imaging in revealing local recurrence of prostatic cancer was 100% (95% confidence interval = 89-100%), and the specificity also was 100% (95% confidence interval = 69-100%). The kappa coefficient was 1.0 (p < .001)., Conclusion: MR imaging with a transrectal surface coil is a useful imaging tool to evaluate men who have undergone radical prostatectomy and are suspected of having local recurrence of malignancy in the prostatic bed.

The adrenal glands are affected by complex physiologic and neoplastic processes. Recently described computed tomography densitometry and chemical shift MR imaging techniques are useful to distinguish between benign and malignant masses. Knowledge of the basic gross pathologic and histologic correlates of adrenal disease helps in applying these new imaging methods and in understanding established cross-sectional studies.

Objective: Maintaining high standards in a large CT imaging department with multiple scanners, a large technical and clerical staff, and a rotating staff of radiologists is an ongoing challenge. We undertook a project to design and implement a simple, rapidly performed computer-assisted system of quality assurance (QA) for use in abdominal CT. In our project, we also analyzed the results of that QA system., Materials and Methods: We graded 1810 abdominal CT studies done in a 50-week period, using a three-point scale to indicate the quality of the following five parameters of technical quality: IV contrast enhancement, oral contrast opacification, window settings and artifacts, conformity to radiologists' protocol, and completeness and accuracy of header and scout data. In addition, a parameter reflecting performance of the film library and clerical staff was similarly graded. To provide a measure of peer review for radiologists, any disagreements with prior CT study reports were recorded when comparison studies were reviewed in the process of CT interpretation. A commercially available spreadsheet and database software program was tailored to allow rapid, easily performed data entry and analysis. Tables and graphs showing performance of technologists and film library and clerical staff were generated. This customized program was made available on the radiology department computer network. Results generated by the program were further analyzed with linear regression models., Results: Our QA system was successfully integrated into the routine operation of the abdominal CT division. During the first 11.5 months of operation, the system reflected improvement in each of the technical parameters with a statistically significant improvement in the combined average technical score (from 1.15 to 1.68 on a scale of 0-2; p < .0001). The "Throughout Speed/Old Exams" parameter for performance of the film library and clerical staff, which was analyzed separately from the technical parameters, also improved significantly (from 1.3 to 1.8; p < .02). Improvements were statistically significant, even when we controlled for potential variations in quality among different CT scanners and variations among the radiologists who rated the quality of the examination. Thirty-eight disagreements with previous scan interpretations (5% of all scan comparisons) were recorded for evaluation at peer review conferences., Conclusion: The ability to monitor performance continuously using a rapid, computer-assisted system has effected measurable improvement in our CT service. Technologist and film library and clerical staff performance improved for all parameters studied. Deficiencies were revealed and trends demonstrated. The QA system allowed us to identify disagreements in interpretation of CT examinations for subsequent peer review by radiologists. Our QA software program has been made available on the Internet as freeware to licensed Excel users via anonymous file transfer protocol at Internet Protocol 134.192.6.110.

Objective: Laparoscopic techniques are evolving for a wide range of surgical procedures outside the biliary tree. We describe the CT findings of important complications detected after nonbiliary laparoscopic gastrointestinal surgery and the role of CT in their management., Materials and Methods: Over a 3-year period, 209 patients had nonbiliary gastrointestinal laparoscopic procedures (partial or total colectomy, splenectomy, Nissen fundoplication, lymph-node dissection, herniorrhaphy, appendectomy, and exploratory laparoscopy). Thirty-seven abdominopelvic CT studies were performed on 18 (9%) of these patients for complications after surgery. In all cases CT findings were reviewed and correlated with follow-up surgical, clinical, or interventional radiologic findings., Results: Fourteen major complications were detected on CT in 12 of 18 (67%) patients who had undergone partial or total colectomy (6/25, 24%), splenectomy (4/41, 10%), appendectomy (1/15, 7%), or lymph-node dissection (1/43, 2%). These complications included seven abscesses (three of the splenic bed, two of the pelvis, one of the liver, and one of the abdominal wall). The remaining complications were four hematomas (two in the abdominal wall caused by trocar site bleeding, one intraperitoneal, and one retroperitoneal), one case of colon perforation, one case of pancreatitis, and one case of splenic infarction. Percutaneous abscess drainage was performed successfully in seven patients, using CT guidance in six. Six patients had negative CT studies., Conclusion: Major complications may occur after complex nonbiliary laparoscopic procedures and are probably related to lack of experience with new surgical techniques. In this study, such complications occurred most often after laparoscopic colectomy and splenectomy. CT valuable in their diagnosis and in the management of abscess collections.

Purpose: To compare seven large-core, long-throw, 14-gauge biopsy guns for yield and quality of breast tissue obtained., Materials and Methods: A two-phase, randomized and blinded study was performed. In the first phase, four fully automated 14-gauge biopsy guns (BIP, Manan, Biopsy, and ASAP) and one semiautomated device (Temno) were used to obtain breast cores from a cadaver. Samples were assessed for volume, number of fragments, and crush artifact. In the second phase, seven biopsy guns (previously mentioned guns plus Monopty and Ultra-Cut guns) were used to obtain cores from a breast parenchyma model. These cores were then evaluated for weight, volume, and number of fragments., Results: The mean specimen volume of cadaveric breast tissue obtained was 17.9 mm3 for the BIP gun, 17.8 for the Manan gun, 14.9 for the Biopsy gun, 14.1 for the ASAP gun, and 9.9 for the Temno gun. The Temno gun obtained statistically significantly smaller volumes than all other guns. For the breast parenchyma model, mean obtained volumes were 24.5, 24.1, 16.2, 21.7, 17.5, 20.0, and 15.2 mm3, respectively. The BIP and Manan guns yielded statistically significantly larger cores than all other guns except the ASAP., Conclusion: Yields of breast tissue provided by each biopsy device differed statistically significantly. BIP and Manan biopsy guns yielded the greatest volume of core tissue, which may facilitate histopathologic diagnosis from breast biopsies performed with imaging guidance.

Objective: Despite the increasing success of pancreatic transplantation for diabetes, rejection remains the most common cause of graft loss. The purpose of this study was to correlate gray-scale sonographic morphology and Doppler resistive index (RI) with acute pancreatic transplant rejection as determined by percutaneous, sonographically guided biopsy of the pancreas., Subjects and Methods: Fifty-one sonograms of 36 patients were correlated with sonographically guided biopsies performed for clinically suspected acute rejection. Sonographic studies consisted of gray-scale morphologic assessment of gland size, texture, marginal definition, peripancreatic fluid, and duct dilatation as well as measurement of the average Doppler RI. Biopsies were performed within 48 hr of sonography. After localization by sonography, we performed percutaneous biopsy with an 18-gauge automated biopsy device., Results: Biopsy findings were acute rejection (n = 40, 78%), chronic rejection (n = 2, 4%), and no evidence of rejection (n = 9, 18%). Procedure-related hemorrhage occurred in one patient and resolved spontaneously. Gray-scale sonographic abnormalities were present in 37 studies (73%). The most common abnormality was pancreatic enlargement (n = 23) with a sensitivity and specificity of 58% and 100%, respectively, for acute rejection. Loss of marginal definition occurred in nine studies with a sensitivity and specificity of 15% and 73%, respectively, for acute rejection. An RI > or = 0.7 was found in 11 studies (22%) with a sensitivity of 20% and a specificity of 73% for acute rejection., Conclusion: For the diagnosis of acute pancreatic rejection, sonographically guided percutaneous biopsy is superior to gray-scale and spectral Doppler sonography. Sonographically guided percutaneous biopsy is a safe technique with a high success rate. Gray-scale and spectral Doppler sonography lack sensitivity, and a normal RI should not delay biopsy.

The present study was designed to investigate biomechanical and clinical changes in the mandibular complex by means of finite element analysis. An analytical model developed from human native mandibles was used for this model, CT image data were transferred to a computer, and an edge extraction program generated the cross-section of bone by specifying a range of CT values for each slice. Pixel data from the CT scan were converted into a vector of points (x, y, z) which can specify the boundaries of bone. Lateral surfaces are defined by stacking up the slices and making use of the vectorized data. The constructed model was used as input data for the finite element analysis. The models were solved for stresses and forces. The highest principal stresses occurred at the bite point, anterior aspects of the coronoid processes, symphyseal region, and right and left sides of the mandibular corpus. For further investigation muscular structures have to be integrated to establish a model, which can be analysed under multivariate aspects.

Objective: We describe the CT findings of medial transfer of a sartorius muscle flap, which is done to protect the femoral blood vessels after radical inguinal lymphadenectomy for cancer or surgical debridement of infected femoral vascular grafts., Materials and Methods: We reviewed the appearances and initial interpretations of 33 CT studies in 17 patients who underwent medial sartorius flap transfer after either (1) inguinal lymphadenectomy for melanoma or penile cancer or (2) debridement of infected groin wounds complicating vascular reconstruction of the femoral arteries. Muscle flap transfer was defined by the surgical record as either complete or incomplete. In complete sartorius muscle transfer, the proximal end of the muscle is dissected from the anterior superior iliac spine, rotated along its long axis, and sutured medially to the inguinal ligament. In incomplete transfer, the muscle it mobilized and stretched medially, and its medial border is fixed to the inguinal ligament and deep tissues. Clinical correlation and follow-up examinations were done for all patients, and CT reevaluation at intervals was done in nine patients., Results: Complete sartorius flap transfer resulted in a mass anterolateral or anterior to the femoral vessels on postoperative CT scans in 20 studies; five of these masses were misinterpreted initially as possible recurrent metastatic lymphadenopathy, infection, or hematoma. Incomplete sartorius flap transfer resulted in bandlike stretching of the muscle over the femoral vessels in 13 studies., Conclusion: Medial transfer of the sartorius muscle causes a variable appearance of the groin on CT scans. The findings on CT scans after complete sartorius flap transfer should be distinguished from recurrent lymphadenopathy and from postoperative phlegmon or hematoma.

Purpose: To determine the value of magnetic resonance (MR) angiography and MR imaging with dynamic gadopentetate dimeglumine-enhanced gradient-echo (Gd-GRE) sequences in detection of vascular complications of pancreatic transplantation., Materials and Methods: Three radiologists evaluated findings of 32 MR examinations in 20 adult patients who underwent pancreatic transplantation. The images were obtained with a surface coil and T1-weighted and T2-weighted fast spin-echo sequences, Gd-GRE sequences, and MR angiography. Vascular abnormality was confirmed at surgery or biopsy, and vascular patency with clinical correlation., Results: Absence of flow was found in six of 32 studies (19%): acute vascular thrombosis of the vascular pedicle and/or branch vessels in four studies (three patients) and chronic pancreatic rejection in two studies (one patient). Gd-GRE images helped identify infarction in two patients. The sensitivity of MR angiography for detection of acute vascular compromise was 100%, and the specificity was 93%., Conclusion: MR angiography and MR imaging with Gd-GRE sequences allow detection of vascular complications of pancreatic transplantation.