Short Note on the Density of States in 3D Weyl Semimetals.

The average density of states in a disordered three-dimensional Weyl system is discussed in the case of a continuous distribution of random scattering. Our results clearly indicate that the average density of states does not vanish, reflecting the absence of a critical point for a metal-insulator transition. This calculation supports recent suggestions of an avoided quantum critical point in the disordered three-dimensional Weyl semimetal. However, the effective density of states can be very small such that the saddle-approximation with a vanishing density of states might be valid for practical cases.

Human pregnancy is accompanied by modifications in B cell development and immunoglobulin profile.

Though human pregnancy success has been classically linked with a shift into a Th2 immunoglobulin producing cell response, a clear picture concerning B cell development and immunoglobulin profile during human pregnancy is missing. We analyzed in this work the dynamic of different B cell populations in peripheral blood of pregnant women on the first, second and third trimester of pregnancy. As control, age-matched non-pregnant fertile women were included. Additionally, we quantified the levels of immunoglobulin (IgG1, IgG2, IgG3, IgG4, IgM, IgA and IgE) in the serum of pregnant and non-pregnant women. We observed a significant decrease in the percentages of transitional B cells in peripheral blood of pregnant women as compared to non-pregnant control women. Besides, percentages of naïve as well as switched and non-switched memory B cells in peripheral blood of pregnant women were similar to those in non-pregnant control women. Interestingly, although we did not observe differences in the activation status of B cells as well as in the percentages of plasma cells between pregnant and non-pregnant women, we observed significantly higher levels of IgM, IgA, IgG3, more likely natural antibodies, as well IgG4 in serum of pregnant women compared to non-pregnant age matched control women.

Myeloid protein tyrosine phosphatase 1B (PTP1B) deficiency protects against atherosclerotic plaque formation in the ApoE-/- mouse model of atherosclerosis with alterations in IL10/AMPKα pathway.

OBJECTIVE: Cardiovascular disease (CVD) is the most prevalent cause of mortality among patients with Type 1 or Type 2 diabetes, due to accelerated atherosclerosis. Recent evidence suggests a strong link between atherosclerosis and insulin resistance due to impaired insulin receptor (IR) signaling. Moreover, inflammatory cells, in particular macrophages, play a key role in pathogenesis of atherosclerosis and insulin resistance in humans. We hypothesized that inhibiting the activity of protein tyrosine phosphatase 1B (PTP1B), the major negative regulator of the IR, specifically in macrophages, would have beneficial anti-inflammatory effects and lead to protection against atherosclerosis and CVD. METHODS: We generated novel macrophage-specific PTP1B knockout mice on atherogenic background (ApoE-/-/LysM-PTP1B). Mice were fed standard or pro-atherogenic diet, and body weight, adiposity (echoMRI), glucose homeostasis, atherosclerotic plaque development, and molecular, biochemical and targeted lipidomic eicosanoid analyses were performed. RESULTS: Myeloid-PTP1B knockout mice on atherogenic background (ApoE-/-/LysM-PTP1B) exhibited a striking improvement in glucose homeostasis, decreased circulating lipids and decreased atherosclerotic plaque lesions, in the absence of body weight/adiposity differences. This was associated with enhanced phosphorylation of aortic Akt, AMPKα and increased secretion of circulating anti-inflammatory cytokine interleukin-10 (IL-10) and prostaglandin E2 (PGE2), without measurable alterations in IR phosphorylation, suggesting a direct beneficial effect of myeloid-PTP1B targeting. CONCLUSIONS: Here we demonstrate that inhibiting the activity of PTP1B specifically in myeloid lineage cells protects against atherosclerotic plaque formation, under atherogenic conditions, in an ApoE-/- mouse model of atherosclerosis. Our findings suggest for the first time that macrophage PTP1B targeting could be a therapeutic target for atherosclerosis treatment and reduction of CVD risk.

Superior functional outcome after femoral derotation osteotomy according to gait analysis in cerebral palsy.

The femoral derotation osteotomy (FDO) is seen as the golden standard treatment in children with cerebral palsy and internal rotation gait. Variable outcomes with cases of over- and undercorrection mainly in the less involved patients have been reported. The determination of the amount of derotation is still inconsistent. 138 patients (age: 11 (± 3.3) years) with cerebral palsy and internal rotation gait were examined pre- and 1 year postoperatively after distal or proximal FDO, using standardized clinical examination and 3D gait analysis. Three groups were defined retrospectively depending on the amount of derotation in relation to the mean hip rotation in stance (MHR) during gait analysis: Group A (derotation angle > MHR + 10°), Group B (derotation angle = MHR ± 10°), Group C (derotation angle

Mobile stroke unit for diagnosis-based triage of persons with suspected stroke.

BACKGROUND: In this feasibility study, we tested whether prehospital diagnostic stroke workup enables rational decision-making regarding treatment and the target hospital in persons with suspected stroke. METHODS: A mobile stroke unit that delivers imaging (including multimodal brain imaging with CT angiography and CT perfusion), point-of-care-laboratory analysis, and neurologic expertise directly at the emergency site was analyzed for its use in prehospital diagnosis-based triage of suspected stroke patients. RESULTS: We present 4 complementary cases with suspected stroke who underwent prehospital diagnostic workup that enabled direct diagnosis-based treatment decisions and reliable triage regarding the most appropriate medical facility for that individual, e.g., a primary hospital vs specialized centers of a tertiary hospital. CONCLUSIONS: This preliminary report demonstrates the feasibility of prehospital diagnostic stroke workup for immediate etiology-specific decision-making regarding the necessary time-sensitive stroke treatment and the most appropriate target hospital.

Pancreatic enucleation: improved outcomes compared to resection.

INTRODUCTION: Pancreatic enucleation is associated with a low operative mortality and preserved pancreatic parenchyma. However, enucleation is an uncommon operation, and good comparative data with resection are lacking. Therefore, the aim of this analysis was to compare the outcomes of pancreatic enucleation and resection. MATERIAL AND METHODS: From 1998 through 2010, 45 consecutive patients with small (mean, 2.3 cm) pancreatic lesions underwent enucleation. These patients were matched with 90 patients undergoing pancreatoduodenectomy (n = 38) or distal pancreatectomy (n = 52). Serious morbidity was defined in accordance with the American College of Surgeons-National Surgical Quality Improvement Program. Outcomes were compared with standard statistical analyses. RESULTS: Operative time was shorter (183 vs. 271 min, p < 0.01), and operative blood loss was significantly lower (160 vs. 691 ml, p < 0.01) with enucleation. Fewer patients undergoing enucleation required monitoring in an intensive care unit (20% vs. 41%, p < 0.02). Serious morbidity was less common among patients who underwent enucleation compared to those who had a resection (13% vs. 29%, p = 0.05). Pancreatic endocrine (4% vs. 17%, p = 0.05) and exocrine (2% vs. 17%, p < 0.05) insufficiency were less common with enucleation. Ten-year survival was no different between enucleation and resection. CONCLUSION: Compared to resection, pancreatic enucleation is associated with improved operative as well as short- and long-term postoperative outcomes. For small benign and premalignant pancreatic lesions, enucleation should be considered the procedure of choice when technically appropriate.

Occurrence of biogenic amine-forming lactic acid bacteria in wine and cider.

A collection of 810 lactic acid bacteria (LAB) strains isolated from wine and cider was screened for potential biogenic amine (BA) producers by combining molecular and phenotypic approaches. A newly developed multiplex PCR method allowed for the simultaneous detection of four genes involved in the production of histamine (histidine decarboxylase, hdc), tyramine (tyrosine decarboxylase, tyrdc) and putrescine (via either ornithine decarboxylase, odc, or agmatine deiminase, agdi) while TLC and HPLC analysis allowed for BA-production determination. One hundred and fifty-eight LAB strains were monitored by the molecular/phenotypic double approach and revealed a good correlation between genotypic and phenotypic data. Eighteen per cent of the tested strains were positive for at least one BA target gene with up to three detected simultaneously, in particular amongst Lactobacillus brevis and Lactobacillus hilgardii isolates for the tyrdc and agdi genes. The most frequent gene corresponded to the agdi gene detected in 112 strains (14% of all LAB strains) of 10 different LAB species. The tyrdc gene was detected in 67 strains represented by 7 different LAB species (8% overall), especially those isolated from wine. Lower levels of hdc(+) (2% of strains) and especially odc(+) (0.5% of strains) strains were observed. Interestingly, species that have never been described to carry BA-producing pathway genes were identified in this study. Furthermore, only one cadaverine-producer was detected and corresponded to Lactobacillus 30a, a collection strain not found in fermented beverages, although cadaverine is commonly detected in wines.

Tunable band gap in hydrogenated quasi-free-standing graphene.

We show by angle-resolved photoemission spectroscopy that a tunable gap in quasi-free-standing monolayer graphene on Au can be induced by hydrogenation. The size of the gap can be controlled via hydrogen loading and reaches approximately 1.0 eV for a hydrogen coverage of 8%. The local rehybridization from sp(2) to sp(3) in the chemical bonding is observed by X-ray photoelectron spectroscopy and X-ray absorption and allows for a determination of the amount of chemisorbed hydrogen. The hydrogen induced gap formation is completely reversible by annealing without damaging the graphene. Calculations of the hydrogen loading dependent core level binding energies and the spectral function of graphene are in excellent agreement with photoemission experiments. Hydrogenation of graphene gives access to tunable electronic and optical properties and thereby provides a model system to study hydrogen storage in carbon materials.

Whole blood-derived miRNA profiles as potential new tools for ovarian cancer screening.

BACKGROUND: Screening is an unsolved problem for ovarian cancer (OvCA). As late detection is equivalent to poor prognosis, we analysed whether OvCA patients show diagnostically meaningful microRNA (miRNA) patterns in blood cells. METHODS: Blood-borne whole miRNome profiles from 24 patients with OvCA and 15 age- and sex-matched healthy controls were biostatistically evaluated. RESULTS: Student's t-test revealed 147 significantly deregulated miRNAs before and 4 after Benjamini-Hochberg adjustment. Although these included miRNAs already linked to OvCA (e.g., miR-16, miR-155), others had never before been connected to specific diseases. A bioinformatically calculated miRNA profile allowed for discrimination between blood samples of OvCA patients and healthy controls with an accuracy of >76%. When only cancers of the serous subtype were considered and compared with an extended control group (n=39), accuracy, specificity and sensitivity all increased to >85%. CONCLUSION: Our proof-of-principle study strengthens the hypothesis that neoplastic diseases generate characteristic miRNA fingerprints in blood cells. Still, the obtained OvCA-associated miRNA pattern is not yet sensitive and specific enough to permit the monitoring of disease progression or even preventive screening. Microarray-based miRNA profiling from peripheral blood could thus be combined with other markers to improve the notoriously difficult but important screening for OvCA.

Random-gap model for graphene and graphene bilayers.

The effect of a randomly fluctuating gap, created by a random staggered potential, is studied in a monolayer and a bilayer of graphene. The density of states, the one-particle scattering rate, and the transport properties (diffusion coefficient and conductivity) are calculated at the neutrality point. All of these quantities vanish at a critical value of the average staggered potential, signaling a continuous transition to an insulating behavior. Transport quantities are directly linked to the one-particle scattering rate. Although the behavior is qualitatively the same in mono- and bilayers, the effect of disorder is much stronger in the latter.

[Freezing of gait : phenomenology, pathophysiology, and therapeutic approaches]. / Freezing während des Gehens : Phänomen, Pathophysiologie, Therapie.

Freezing of gait (FOG) is a common disturbance in Parkinson's disease (PD) and other higher-level gait disorders. It appears most often during the later stages of PD but is seen also during the initial phases before oral substitution of levodopa has started. The disorder has its own pathophysiology and differs from bradykinesia. It can occur both on and off medication. It interferes with activities of daily life, reduces mobility, and is an important risk factor for falling. While patients with FOG during medication do not reliably respond to pharmacotherapy or deep brain stimulation, external cues have been demonstrated that influence FOG effectively. They are applied as auditory, visual, tactile, or mental cues. This article discusses available pharmacological and physiotherapeutic approaches to the treatment of FOG.

Suppression of magnetotransport in strongly disordered graphene.

A tight-binding model with randomly fluctuating atomic positions is studied to discuss the effect of strong disorder in graphene. We employ a strong-disorder expansion for the transport quantities and find a diffusive behavior, where the conductivity is decreasing with increasing disorder. For sufficiently strong disorder the magnetic field drops out of the diffusion coefficient and the conductivity. This signals a strong suppression of magnetotransport effects, a result which is consistent with recent experimental observations by Morozov et al.

Nonlinear electromagnetic response of graphene: frequency multiplication and the self-consistent-field effects.

Graphene is a recently discovered carbon-based material with unique physical properties. This is a monolayer of graphite, and the two-dimensional electrons and holes in it are described by the effective Dirac equation with a vanishing effective mass. As a consequence, the electromagnetic response of graphene is predicted to be strongly nonlinear. We develop a quasi-classical kinetic theory of the nonlinear electromagnetic response of graphene, taking into account the self-consistent-field effects. The response of the system to both harmonic and pulse excitation is considered. The frequency multiplication effect, resulting from the nonlinearity of the electromagnetic response, is studied under realistic experimental conditions. The frequency upconversion efficiency is analyzed as a function of the applied electric field and parameters of the samples. Possible applications of graphene in terahertz electronics are discussed.

New electromagnetic mode in graphene.

A new, weakly damped, transverse electromagnetic mode is predicted in graphene. The mode frequency omega lies in the window 1.667<[see text]omega/micro < 2, where micro is the chemical potential, and can be tuned from radio waves to the infrared by changing the density of charge carriers through a gate voltage.

Reduced cellular toxicity of a new silver-containing antimicrobial dressing and clinical performance in non-healing wounds.

Bacterial colonisation of wounds may delay wound healing. Modern silver-containing dressings are antimicrobial, yet cellular toxicity is a serious side-effect. We provide data for a newly formulated silver-containing ointment dressing, Atrauman Ag, for antimicrobial activity and cytotoxicity. Atrauman Ag effectively killed a panel of commensal skin as well as pathogenic bacterial strains while cytotoxicity for HaCaT keratinocytes was only around 10%. With these favourable in vitro tests, Atrauman Ag was analysed in 86 patients with traumatic and non-healing wounds of different aetiologies. The wound state was evaluated for 3 subsequent dressing changes. The slough score was reduced from 59.2 to 35.8%, granulation tissue increased from 27 to 40% and epithelialisation went up from 12.1 to 24%. We conclude that Atrauman Ag has a superior profile of antimicrobial activity over cellular toxicity and the low silver ion release rate may prevent interference with wound-healing mechanisms.

Robust transport properties in graphene.

Two-dimensional Dirac fermions are used to discuss quasiparticles in graphene in the presence of impurity scattering. Transport properties are completely dominated by diffusion. This may explain why recent experiments did not find weak localization in graphene. The diffusion coefficient of the quasiparticles decreases strongly with increasing strength of disorder. Using the Kubo formalism, however, we find a robust minimal conductivity that is independent of disorder. This is a consequence of the fact that the change of the diffusion coefficient is fully compensated by a change of the number of delocalized quasiparticle states.

Impact of reflux disease on general and disease-related quality of life - evidence from a recent comparative methodological study in Germany.

BACKGROUND: The clinical and socioeconomic burden of gastro-esophageal reflux disease (GERD) is considerable. The primary symptom of GERD is heartburn, but it may also be associated with extraesophageal manifestations, such as asthma, chest pain and otolaryngologic disorders. AIM: To describe the impact of heartburn on patients' Health-Related Quality of Life (HRQL) in Germany, using validated generic and disease-specific instruments to measure patient-reported outcomes. METHOD: Patients with symptoms of heartburn completed the German versions of the Gastrointestinal Symptom Rating Scale (GSRS), the Quality of Life in Reflux and Dyspepsia questionnaire (QOLRAD), the Short Form-36 (SF-36) and the Hospital Anxiety and Depression (HAD) scale. Frequency and severity of heartburn during the previous 7 days were also recorded. RESULTS: 142 consecutive patients completed the assessments (mean age of 47.5 years, SD = 14.6; 55.6 % female). 70 % of patients had moderate symptoms. Over half (68 %) had symptoms on more than 4 days in the previous week. Patients were most bothered by symptoms of reflux with a mean GSRS score, (ranges from 1 [not bothered] to 7 [very bothered]), of 3.9, indigestion of 3.3 and abdominal pain of 3.0, respectively. As a result of their symptoms, patients experienced problems with food and drink. The mean QOLRAD score (ranges from 1 to 7; the lower the value the more severe the impact on quality of life) of daily functioning was 4.4, impaired vitality 4.6, emotional distress 5.0 and sleep disturbance 5.1, respectively. This led to impaired overall HRQL across all domains (mean SF-36 score of this heartburn population compared to a general population in Germany). Using HAD, 25 % of patients were anxious and 8 % were depressed. CONCLUSION: There is consistent evidence that heartburn substantially impairs all aspects of health-related quality of life.

[The importance of conventional radiographs in the diagnosis of osteosarcoma]. / Die Bedeutung von Nativröntgenaufnahmen in der Diagnosestellung des Osteosarkoms.

We report about a 12-year-old boy with a history of recurrent patella luxation. Due to persistent pain in the distal left femur a MRI examination was performed in another hospital which suggested a malignant bone tumor. Without validation of the MRI findings by conventional radiographs bone biopsy was performed. Histopathological examination yielded the diagnosis of a chondroblastic osteosarcoma. Before initiating polychemotherapy, plain radiographs for the first time, a nuclear imaging study and an additional MRI examination were performed in our hospital. The results of these studies made the diagnosis of an osteosarcoma unlikely. In particular, plain radiographs did not show any osseous lesion which was characteristic of an osteosarcoma. To establish a definite diagnosis biopsy was repeated with resection of the bone area which showed suspicious changes in MRI studies. An osteosarcoma was ruled out by histopathological examination. The pathologic changes detected in MRI were rated as bone bruise on plain radiographs and seemed to be of traumatic origin. Our case report emphasises the importance of conventional radiographs in establishing the diagnosis of an osteoarcoma respectively bone tumors and tumor-like lesions in general. They still remain the mainstay in diagnosing bone forming tumors. MRI imaging studies may show changes which mimick solid lesions but in deed can be of traumatic origin. Without informing the pathologist about the exact origin of the specimen, histopathological examination may lead to the misdiagnosis of a chondroblastic osteosarcoma if specimen, like in this case report, represents epiphyseal tissue showing cartilaginous areas with reactive bone formation.