[Pseudolymphatic allergic immune reaction after tattooing]

Allergic reactions occurring after tattooing, especially after the use of red tattoo ink ingredients are relatively rare. We report a painful skin reaction occurring 6 months after the tattoing of the right lower extremity in a 30-year-old female patient. Pathohistological and immunchemical results confirmed a pseudolymphoma. Only the tangential excision of the affected areas led to a sufficient healing process. Split thickness skin grafts were used for defect coverage. 2 years later, the patient was still pain free and the wounds had healed completely without any irritation.

A novel CO2- and SO2-tolerant dual phase composite membrane for oxygen separation

Here we report a novel, cheap, non-toxic, CO₂- and SO₂-stable dual phase composite oxygen transport membrane (Al_0.02Ga_0.02Zn_0.96O_1.02–Gd_0.1Ce_0.9O_1.95−δ) for oxygen separation.

Vacancy patterning and patterning vacancies: controlled self-assembly of fullerenes on metal surfaces

A density functional theory study accounting for van der Waals interactions reveals the potential of metal surface vacancies as anchor points for the construction of user-defined 2D patterns of adsorbate molecules via a controlled self-assembly process. Vice versa, energetic criteria indicate the formation of regular adsorbate-induced vacancies after adsorbate self-assembly on clean surfaces. These processes are exemplified by adsorbing C₆₀ fullerene on Al(111), Au(111), and Be(0001) surfaces with and without single, triple, and septuple atom pits. An analysis of vacancy-adatom formation energetics precedes the study of the adsorption processes.

[Cutaneous infection with Aggregatibacter actinomycetemcomitans]

BACKGROUND

Aggregatibacter actinomycetemcomitans is a small, gram-negative, non-motile, coccobacillus. Aggregatibacter actinomycetemcomitans is known to cause periodontal disease and to be associated with actinomycosis.

CASE REPORT

We report a patient developed a chronic wound following trauma about the right heel. The lesion resolved after oral antibiotic therapy with cefpodoxime und surgical debridement. Bacterial cultures grew abundant Aggregatibacter actinomycetemcomitans, but no actinomyces species.

OBJECTIVE

The importance of Aggregatibacter actinomycetemcomitans in chronic wounds needs to be explored.

Ordered phases of ethylene adsorbed on charged fullerenes and their aggregates

In spite of extensive investigations of ethylene adsorbed on graphite, bundles of nanotubes, and crystals of fullerenes, little is known about the existence of commensurate phases; they have escaped detection in almost all previous work. Here we present a combined experimental and theoretical study of ethylene adsorbed on free C₆₀ and its aggregates. The ion yield of [Formula: see text] measured by mass spectrometry reveals a propensity to form a structurally ordered phase on monomers, dimers and trimers of C₆₀ in which all sterically accessible hollow sites over carbon rings are occupied. Presumably the enhancement of the corrugation by the curvature of the fullerene surface favors this phase which is akin to a hypothetical 1 × 1 phase on graphite. Experimental data also reveal the number of molecules in groove sites of the C₆₀ dimer through tetramer. The identity of the sites, adsorption energies and orientations of the adsorbed molecules are determined by molecular dynamics calculations based on quantum chemical potentials, as well as density functional theory. The decrease in orientational order with increasing temperature is also explored in the simulations whereas in the experiment it is impossible to vary the temperature.

[Acute complications after endoscopic resection of duodenal adenomas]

With the increasing technological development of endoscopy in recent years the diagnosis of and endoscopic therapy for duodenal adenomas has gained in importance. Due to its potentially malignant transformation an effective and safe therapy is necessary. The endoscopic resection has been shown to be safe and effective, even in cases of resection of large duodenal adenomas. Several studies have supported this thesis but are based on relatively small numbers of patients. In our clinic we have performed endoscopic resections of 178 duodenal adenomas over a period of 14 years, including sporadic duodenal adenomas as well as adenomas in familial polyposis syndromes. The aim of this retrospective analysis was to determine the acute complications associated with this technique. The rate of severe complications such as major bleeding or perforations was 9%. Further complications were minor bleeding (15.7%), pain needing treatment with analgesia (6.7%), fever (2.8%) and pancreatitis (0.6%). Summing up our experience with the endoscopic resection of adenomas of the small bowel we also consider the endoscopic resection of duodenal adenomas in most cases as a safe and effective alternative to surgical therapy. Because of the potential complications and their management especially in the resection of large adenomas with a size more than 2 cm, the endoscopic resection should be performed on an inpatient basis in experienced centres.

Ethylene glycol revisited: Molecular dynamics simulations and visualization of the liquid and its hydrogen-bond network

Molecular dynamics simulations of liquid ethylene glycol described by the OPLS-AA force field were performed to gain insight into its hydrogen-bond structure. We use the population correlation function as a statistical measure for the hydrogen-bond lifetime. In an attempt to understand the complicated hydrogen-bonding, we developed new molecular visualization tools within the Vish Visualization shell and used it to visualize the life of each individual hydrogen-bond. With this tool hydrogen-bond formation and breaking as well as clustering and chain formation in hydrogen-bonded liquids can be observed directly. Liquid ethylene glycol at room temperature does not show significant clustering or chain building. The hydrogen-bonds break often due to the rotational and vibrational motions of the molecules leading to an H-bond half-life time of approximately 1.5 ps. However, most of the H-bonds are reformed again so that after 50 ps only 40% of these H-bonds are irreversibly broken due to diffusional motion. This hydrogen-bond half-life time due to diffusional motion is 80.3 ps. The work was preceded by a careful check of various OPLS-based force fields used in the literature. It was found that they lead to quite different angular and H-bond distributions.

Bladder augmentation with small intestinal submucosa leads to unsatisfactory long-term results

PURPOSE

To evaluate the use of small intestinal submucosa (SIS) for bladder augmentation in a series of select patients.

MATERIAL AND METHODS

Six patients (age 6.5-15.4, mean 9.8 years) underwent bladder augmentation with SIS: one after a cloacal exstrophy repair, one after multiple surgery of the bladder because of vesicoureteral reflux, two with spina bifida, two after bladder exstrophy repair. All suffered from a microbladder with a mean volume of 61.5 ml (range 15-120, 7-36% of expected bladder capacity for age). Preoperative bladder compliance ranged from 1.0 to 3.3 (mean 1.3) ml/cmH2O.

RESULTS

Follow-up time ranged from 4.6 to 33.5 (mean 24.4) months. An increase of bladder volume was achieved in four patients (53-370 ml, 16-95% of expected bladder capacity for age). Bladder compliance postoperatively ranged from 0.9 to 5.6 (mean 3.0) ml/cmH2O. Histological examinations showed a complete conversion of SIS, leaving irregular urothelial lining and bladder wall containing muscular, vascular and relatively thick connective tissue in four patients and regular urothelium in two patients. Major complications were bladder stones in two patients and a bladder rupture in one patient.

CONCLUSION

Bladder augmentation with SIS in humans failed to fulfill the hopes raised by animal studies. Due to the insufficient increase in bladder compliance and therefore failure to accomplish sufficient protection of the upper urinary tract, bladder augmentation with SIS cannot be recommended as a substitute for enterocystoplasty.

Decorating (C60) n+, n = 1-3, with CO2 at low temperatures: Sterically enhanced physisorption

Multiple attachment of CO₂ to the monomer, dimer and trimer cations of C₆₀ has been observed in the mass spectra of He nanodroplets sequentially doped with C₆₀ and CO₂ and exposed to electron ionization at 50 eV. Remarkable anomalies were seen in the ion yield for CO₂ coverage for (C₆₀)₂⁺(CO₂)₈ and (C₆₀)₃⁺(CO₂)_1,2. These provide insight into the influence of steric properties on the nature of physisorption. The enhanced stabilities of (C₆₀)₂⁺(CO₂)₈ and (C₆₀)₃⁺(CO₂)_1,2 are attributed to physisorption inside the "groove" of the dimer and the two "dimples" in the trimer cations of C₆₀. Molecular dynamics simulations provide a qualitative assessment of the observed physisorption and a useful visualization of structural aspects.

Higher precision level at individual laying performance tests in noncage housing systems

With the Weihenstephan funnel nest box, 12 laying hen flocks were tested for their individual laying performance, egg quality, and nesting behavior in a noncage environment. During the whole observation period of 8 yr, a transponder-based data recording system was continuously improved and resulted in a recording accuracy of 97%. At peak production, heritabilities for the number of eggs laid are in some flocks higher than expected. With improved data accuracy, heritability estimates on individual egg weights are more stable. Heritabilities for nesting behavior traits range between a low to moderate level, providing very useful information for laying hen selection to help improve traits that cannot be recorded in cages. Over the years, the benefits of the Weihenstephan funnel nest box for laying hen breeders have grown. This is due to higher data recording accuracies and extended testing capacities, which result in more reliable genetic parameters.

Adsorption of hydrogen on neutral and charged fullerene: experiment and theory

Helium droplets are doped with fullerenes (either C60 or C70) and hydrogen (H2 or D2) and investigated by high-resolution mass spectrometry. In addition to pure helium and hydrogen cluster ions, hydrogen-fullerene complexes are observed upon electron ionization. The composition of the main ion series is (H2)(n)HC(m)(+) where m = 60 or 70. Another series of even-numbered ions, (H2)(n)C(m)(+), is slightly weaker in stark contrast to pure hydrogen cluster ions for which the even-numbered series (H2)(n)(+) is barely detectable. The ion series (H2)(n)HC(m)(+) and (H2)(n)C(m)(+) exhibit abrupt drops in ion abundance at n = 32 for C60 and 37 for C70, indicating formation of an energetically favorable commensurate phase, with each face of the fullerene ion being covered by one adsorbate molecule. However, the first solvation layer is not complete until a total of 49 H2 are adsorbed on C60(+); the corresponding value for C70(+) is 51. Surprisingly, these values do not exhibit a hydrogen-deuterium isotope effect even though the isotope effect for H2/D2 adsorbates on graphite exceeds 6%. We also observe doubly charged fullerene-deuterium clusters; they, too, exhibit abrupt drops in ion abundance at n = 32 and 37 for C60 and C70, respectively. The findings imply that the charge is localized on the fullerene, stabilizing the system against charge separation. Density functional calculations for C60-hydrogen complexes with up to five hydrogen atoms provide insight into the experimental findings and the structure of the ions. The binding energy of physisorbed H2 is 57 meV for H2C60(+) and (H2)2C60(+), and slightly above 70 meV for H2HC60(+) and (H2)2HC60(+). The lone hydrogen in the odd-numbered complexes is covalently bound atop a carbon atom but a large barrier of 1.69 eV impedes chemisorption of the H2 molecules. Calculations for neutral and doubly charged complexes are presented as well.

Capturing self-propelled particles in a moving microwedge

Catching fish with a fishing net is typically done either by dragging a fishing net through quiescent water or by placing a stationary basket trap into a stream. We transfer these general concepts to micron-sized self-motile particles moving in a solvent at low Reynolds number and study their collective trapping behavior by means of computer simulations of a two-dimensional system of self-propelled rods. A chevron-shaped obstacle is dragged through the active suspension with a constant speed v and acts as a trapping "net." Three trapping states can be identified corresponding to no trapping, partial trapping, and complete trapping and their relative stability is studied as a function of the apex angle of the wedge, the swimmer density, and the drag speed v. When the net is dragged along the inner wedge, complete trapping is facilitated and a partially trapped state changes into a complete trapping state if the drag speed exceeds a certain value. Reversing the drag direction leads to a reentrant transition from no trapping to complete trapping and then back to no trapping upon increasing the drag speed along the outer wedge contour. The transition to complete trapping is marked by a templated self-assembly of rods forming polar smectic structures anchored onto the inner contour of the wedge. Our predictions can be verified in experiments of artificial or microbial swimmers confined in microfluidic trapping devices.

Adsorption of Polar and Nonpolar Molecules on Isolated Cationic C60 , C70 , and Their Aggregates

Physisorption on graphite, graphene, nanotubes, and other graphitic structures has been the subject of numerous studies, partly driven by interest in the nature of order in two-dimensional systems, their phase transitions, and the use of graphitic scaffolds for reversible storage of hydrogen at high volumetric density and low mass. In contrast, physisorption on individual fullerenes or small aggregates of fullerenes has remained largely unexplored, last but not least, because of technical challenges. A summary of recent progress in identifying specific adsorption sites on positively charged C₆₀ , C₇₀ , and their aggregates is given in this Minireview. Adsorption energies and storage capacities for helium, hydrogen, methane, oxygen, nitrogen, water, and ammonia are determined. Mass spectrometric data reveal the formation of a commensurate phase in which all hollow sites of C₆₀ or C₇₀ are occupied. This phase is identified for all nonpolar molecules, including oxygen, which does not form a commensurate phase on planar graphite. The polar molecules, on the other hand, do not wet fullerenes and they do not form this commensurate phase. A hierarchy of other distinct adsorption sites are identified for nonpolar molecules, namely, groove sites for fullerene dimers and beyond, and dimple sites for fullerene trimers and beyond. Furthermore, evidence is presented for the preferential adsorption of hydrogen and methane in registered sites on fullerene dimers. The interpretation of experimental data that merely count the number of preferred adsorption sites is aided by molecular dynamics simulations, which utilize interaction potentials derived from ab initio calculations to determine adsorption energies.

Methane adsorption on aggregates of fullerenes: site-selective storage capacities and adsorption energies

Methane adsorption on positively charged aggregates of C60 is investigated by both mass spectrometry and computer simulations. Calculated adsorption energies of 118-281 meV are in the optimal range for high-density storage of natural gas. Groove sites, dimple sites, and the first complete adsorption shells are identified experimentally and confirmed by molecular dynamics simulations, using a newly developed force field for methane-methane and fullerene-methane interaction. The effects of corrugation and curvature are discussed and compared with data for adsorption on graphite, graphene, and carbon nanotubes.

Methane Adsorption on Graphitic Nanostructures: Every Molecule Counts

Bundles of single-walled nanotubes are promising candidates for storage of hydrogen, methane, and other hydrogen-rich molecules, but experiments are hindered by nonuniformity of the tubes. We overcome the problem by investigating methane adsorption on aggregates of fullerenes containing up to six C(60); the systems feature adsorption sites similar to those of nanotube bundles. Four different types of adsorption sites are distinguished, namely, registered sites above the carbon hexagons and pentagons, groove sites between adjacent fullerenes, dimple sites between three adjacent fullerenes, and exterior sites. The nature and adsorption energies of the sites in C(60) aggregates are determined by density functional theory and molecular dynamics (MD) simulations. Excellent agreement between experiment and theory is obtained for the adsorption capacity in these sites.

Body size is not critical for critical PO2 in scarabaeid and tenebrionid beetles

Constraints on oxygen delivery potentially limit animal body size. Because diffusion rates are highly distance dependent, and because tracheal length increases with size, gas exchange was traditionally thought to be more difficult for larger insects. As yet the effect of body size on critical oxygen partial pressure (Pcrit) has not been measured for any clade of insect species for which there are interspecific data on tracheal scaling. We addressed this deficiency by measuring Pcrit over a 4150-fold mass range (ratio of largest to smallest species mean) of two families of Coleoptera (Tenebrionidae and Scarabaeidae). We exposed adult beetles to progressively lower oxygen levels and measured their ability to maintain CO2 release rates. Absolute metabolic rates increased hypometrically with beetle body mass (M) at both normoxic (M0.748) and hypoxic (M0.846) conditions. Pcrit, however, was independent of body size. Maximum overall conductances for oxygen from air to mitochondria (GO2,max) matched metabolic rates as insects became larger, likely enabling the similar Pcrit values observed in large and small beetles. These data suggest that current atmospheric oxygen levels do not limit body size of insects because of limitations on gas exchange. However, increasing relative investment in the tracheal system in larger insects may produce trade-offs or meet spatial limits that constrain insect size.

How to capture active particles

In many applications, it is important to catch collections of autonomously navigating microbes and man-made microswimmers in a controlled way. Using computer simulation of a two-dimensional system of self-propelled rods we show that a static chevron-shaped wall represents an excellent trapping device for self-motile particles. Its catching efficiency can be controlled by varying the apex angle of the trap which defines the sharpness of the cusp. Upon decreasing the angle we find a sequence of three emergent states: no trapping at wide angles followed by a sharp transition towards complete trapping at medium angles and a crossover to partial trapping at small cusp angles. A generic trapping "phase diagram" maps out the conditions at which the capture of active particles at a given density is rendered optimal.

Multifocal epithelioid hemangioendothelioma derived from the spine region: case report and literature review

Background

Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor with malignant biological behavior. It arises from endothelial cells, usually within soft tissues, and can occur in almost all locations.

Case Report

We report a unique case of a 25-year-old man who presented with sudden attacks of severe back pain followed by acute non-traumatic paraplegia. Emergency diagnostics revealed a pathologic fracture of the T7 vertebra with tumor tissue invasion of the spinal canal. Furthermore, multifocal metastases were found.

Results

To achieve en bloc resection, interdisciplinary surgical approaches were indicated. Despite multimodal therapy concepts, including radiotherapy and chemotherapy as well as endovascular embolization, the patient died within 8 weeks.

Conclusion

Prognosis of EHE is unpredictable and mainly determined by its location. The lesions are potentially aggressive; therefore, en bloc resection should be attempted whenever possible. However, as shown in the literature, only 15% of patients are suitable for total resection.