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The world's power systems are facing a structural change including liberalization of markets and integration of renewable energy sources. This paper describes the challenges that lie ahead in this process and points out avenues for overcoming different problems at different scopes, ranging from individual homes to international super-grids. We apply energy system models at those different scopes and find a trade-off between technical and social complexity. Small-scale systems would require technological breakthroughs, especially for storage, but individual agents can and do already start to build and operate such systems. In contrast, large-scale systems could potentially be more efficient from a techno-economic point of view. However, new political frameworks are required that enable long-term cooperation among sovereign entities through mutual trust. Which scope first achieves its breakthrough is not clear yet. [ABSTRACT FROM AUTHOR]

Purpose: Treatment with metamizole (dipyrone) has steadily increased in Germany over the last decade. The consequences of this increase for metamizole-induced agranulocytosis (MIA) are unclear. The present study addressed this topic using data from the Berlin Case-Control Surveillance Study. Methods: Adult patients (≥18 years of age) with acute nonchemotherapy-induced agranulocytosis were identified by active surveillance in all 51 Berlin hospitals between 2000 and 2010. Cases related to metamizole were ascertained applying the drug causality criteria of the World Health Organization. The incidence rate of MIA was calculated and standardised by age and sex based on the German standard population in 2010. Results: Twenty-six MIA cases out of 88 (30 %) patients with validated agranulocytosis were ascertained. The incidence of MIA was 0.96 (95 % confidence interval (CI) 0.95-0.97) cases per million per year. The median age of MIA cases was 50 years (quartile (Q)1 31 years; Q3 68 years) and 19 (73 %) of them were women. In 17 (65 %) cases, neutrophil granulocytes dropped below the value of 0.1 × 10 cells/L with three patients suffering from sepsis. Headache and postoperative pain were the most frequent indications for metamizole in outpatients ( n = 16) and inpatients ( n = 10), respectively. The median treatment duration was 6 days (Q1 4 days; Q3 19 days). Conclusions: MIA persists as a severe condition in current pharmacotherapy. The continuous increase of metamizole applications should be critically assessed, especially in regard to indications in the outpatient setting and with respect to metamizole treatment duration. [ABSTRACT FROM AUTHOR]

Nanoscale biological materials formed by the assembly of defined block-domain proteins control the formation of cellular compartments such as organelles. Here, we introduce an approach to intentionally 'program' the de novo synthesis and self-assembly of genetically encoded amphiphilic proteins to form cellular compartments, or organelles, in Escherichia coli. These proteins serve as building blocks for the formation of artificial compartments in vivo in a similar way to lipid-based organelles. We investigated the formation of these organelles using epifluorescence microscopy, total internal reflection fluorescence microscopy and transmission electron microscopy. The in vivo modification of these protein-based de novo organelles, by means of site-specific incorporation of unnatural amino acids, allows the introduction of artificial chemical functionalities. Co-localization of membrane proteins results in the formation of functionalized artificial organelles combining artificial and natural cellular function. Adding these protein structures to the cellular machinery may have consequences in nanobiotechnology, synthetic biology and materials science, including the constitution of artificial cells and bio-based metamaterials. [ABSTRACT FROM AUTHOR]

Purpose: Drug-induced agranulocytosis (DIAG) is a rare but serious adverse drug reaction. The Berlin Case-Control Surveillance Study (FAKOS) aimed to identify pharmaceuticals with an increased risk for this condition. Methods: Adult patients with acute non-chemotherapy-induced agranulocytosis, developed in hospital or in the outpatient setting, were ascertained by active surveillance in all 51 Berlin hospitals between the years 2000 and 2010. Applying the criteria of the World Health Organization, a standardized drug causality assessment was conducted for each agranulocytosis patient to determine possible drug aetiology. Drug risks were quantified in a case-control design with unconditional logistic regression analysis. Results: Sixty-three out of 88 validated cases of agranulocytosis were identified as being at least probably drug-related. Drug causality assessment resulted in 36 pharmaceuticals with a certain or probable relationship to agranulocytosis. Drugs involved in ≥ 3 cases with a probable or certain causality were metamizole (dipyrone) ( N = 10), clozapine ( N = 6), sulfasalazine ( N = 5), thiamazole ( N = 5), and carbamazepine ( N = 3). In case-control analysis, six drugs were identified with significant odds ratios for DIAG. The highest odds ratios were observed for clozapine, sulfasalazine, and thiamazole. Conclusions: Our findings are generally in agreement with those of earlier case-control studies. The spectrum of drugs causing acute agranulocytosis has not changed considerably over recent years, despite many newly marketed drugs. Evidence for induction of agranulocytosis by some new pharmaceuticals is supported. [ABSTRACT FROM AUTHOR]

Background Glaucoma comprises age-related neurodegenerative diseases of retinal ganglion cells, the worldwide prevalence of which is increasing. Local pharmacotherapy is the primary treatment option, especially in the elderly. But this therapeutic approach may include risks for adverse drug effects and drug-drug interactions, of particular importance in frail nursing home resident populations. Objective The aim of the present study was to investigate anti-glaucoma pharmacotherapy in nursing home residents in the context of multi-morbidity and related systemic comedication. Methods Data for 8,685 nursing home residents with 88,695 drug prescriptions were analysed according to diagnosis and local or systemic pharmacotherapy. Data were provided in anonymous form by a German public health insurance company. Results The study cohort was characterized by a mean age of 83.6 ± 7.3 years (range: 65-106 years), 21 % of nursing home residents were at least 90 years old and 83.7 % were women. For each nursing home resident, an average of 6.0 ± 3.3 different drugs were registered. A diagnosis of glaucoma was recorded in 520 (6.0 %) nursing home residents; all subjects had co-existing medical conditions. Dementia was a frequent co-morbidity, diagnosed in 51.7 % of nursing home residents with glaucoma. Anti-glaucoma drugs contributed to 0.5 % of all prescriptions and were prescribed to 341 nursing home residents. The most frequently used anti-glaucoma ophthalmics were b-blockers (n = 219), followed by prostaglandin analogues (n = 101) and carbonic anhydrase inhibitors (n = 86). Local antiglaucoma therapy was co-prescribed with a systemic pharmacotherapy in 338 nursing home residents. An ophthalmic agent was, on average, combined with 6.5 ± 3.2 prescriptions for systemic agents. Thus, 71.9 % of nursing home residents were prescribed ophthalmic b-blockers and a concomitant antihypertensive medication; local and systemic b-blockers were combined in 20.2 %of these patients. Co-treatment with cardiac glycosides or calcium antagonists was found in 13 % of nursing home residents prescribed ophthalmic parasympathomimetics, and in 14 % of those prescribed ophthalmic b-blockers, with the potential for drug-drug interactions to influence cardiac function. Conclusions Anti-glaucoma pharmacotherapy in nursing home residents is frequently prescribed in the context of polypharmacy. This may modify the efficacy and safety of local and systemic therapies. Therefore, individualized pharmacotherapy that integrates anti-glaucoma drug therapy into the overall treatment rationale in nursing home residents is necessary. However, to realize this concept, further clinical research in nursing home residents is warranted. [ABSTRACT FROM AUTHOR]

Telomere length has emerged as a biological correlate for ageing, which in turn is a risk factor for the manifestation of cardiovascular diseases. This study investigated the relation between leucocyte telomere length (LTL) and its genetic background to cardiac structure and function in patients with arterial hypertension. We analysed a cohort of 1,106 treated hypertensive patients (83.3% males; mean age, 57.9 ± 9.8 years) with an ejection fraction (EF) over 40% and documented cardiovascular disease or target organ damage. LTL and genotypes of single nucleotide polymorphisms (SNPs), previously implicated in LTL, were determined by real-time PCR. The mean left ventricular mass index (LVMI) and EF were 51.8 ± 21.0 g/H and 61.1 ± 9.6%, respectively. In multivariate adjusted analysis, a 1.5-fold LTL was positively related with a 2.2% increase of LVMI (CI = 0.1% to 4.2%, p = 0.044) and an absolute increase in EF of 0.6% (CI = 0.1% to 1.1%, p = 0.028). One SNP near TERC (rs16847897) showed a significant absolute difference in EF dependent on allele status (rs16847897, G allele 2.7%; CI = 0.7% to 4.6%; p = 0.008, p = 0.048, after adjustment for multiple testing). This applied also for two SNPs in BICD1 (rs2630578, C allele −1.8%; CI = −2.8% to −0.7%; p = 0.002, p = 0.018; rs1151026, G allele −1.9%, CI = −3.0% to −0.8%; p < 0.001, p = 0.002) with the extension that a frequent haplotype in BICD1 showed an absolute −1.8% (CI = −3.0% to −0.7%; p = 0.002, p = 0.008) lower EF compared with those lacking this haplotype. Our results point to a role of genetic variants recently implicated in LTL for left ventricular function in hypertensive patients. [ABSTRACT FROM AUTHOR]

We consider atoms with closed shells, i.e. the electron number N is 2, 8, 10,..., and weak electron-electron interaction. Then there exists a unique solution γ of the Dirac–Fock equations $$[D_{g,\alpha}^{(\gamma)},\gamma]=0$$ with the additional property that γ is the orthogonal projector onto the first N positive eigenvalues of the Dirac–Fock operator $$D_{g,\alpha}^{(\gamma)}$$ . Moreover, γ minimizes the energy of the relativistic electron-positron field in Hartree–Fock approximation, if the splitting of $$\mathfrak{H}:=L^2(\mathbb{R}^3)\otimes \mathbb{C}^4$$ into electron and positron subspace is chosen self-consistently, i.e. the projection onto the electron-subspace is given by the positive spectral projection of $$D_{g,\alpha}^{(\gamma)}$$ . For fixed electron-nucleus coupling constant g:=α Z we give quantitative estimates on the maximal value of the fine structure constant α for which the existence can be guaranteed. [ABSTRACT FROM AUTHOR]

Recently the block-diagonalization of Dirac-operators was investigated from a mathematical point of view in the one-particle case [14]. We extend this result to the N-particle case. This leads to a perturbative realization of the Furry picture in the N-particle two-spinor space. [ABSTRACT FROM AUTHOR]

Objective: Evaluation of the benefits of a virtual reality (VR) environment with a head-mounted display (HMD) for decision-making in liver surgery. Background: Training in liver surgery involves appraising radiologic images and considering the patient's clinical information. Accurate assessment of 2D-tomography images is complex and requires considerable experience, and often the images are divorced from the clinical information. We present a comprehensive and interactive tool for visualizing operation planning data in a VR environment using a head-mounted-display and compare it to 3D visualization and 2D-tomography. Methods: Ninety medical students were randomized into three groups (1:1:1 ratio). All participants analyzed three liver surgery patient cases with increasing difficulty. The cases were analyzed using 2D-tomography data (group "2D"), a 3D visualization on a 2D display (group "3D") or within a VR environment (group "VR"). The VR environment was displayed using the "Oculus Rift ™" HMD technology. Participants answered 11 questions on anatomy, tumor involvement and surgical decision-making and 18 evaluative questions (Likert scale). Results: Sum of correct answers were significantly higher in the 3D (7.1 ± 1.4, p < 0.001) and VR (7.1 ± 1.4, p < 0.001) groups than the 2D group (5.4 ± 1.4) while there was no difference between 3D and VR (p = 0.987). Times to answer in the 3D (6:44 ± 02:22 min, p < 0.001) and VR (6:24 ± 02:43 min, p < 0.001) groups were significantly faster than the 2D group (09:13 ± 03:10 min) while there was no difference between 3D and VR (p = 0.419). The VR environment was evaluated as most useful for identification of anatomic anomalies, risk and target structures and for the transfer of anatomical and pathological information to the intraoperative situation in the questionnaire. Conclusions: A VR environment with 3D visualization using a HMD is useful as a surgical training tool to accurately and quickly determine liver anatomy and tumor involvement in surgery. [ABSTRACT FROM AUTHOR]

Background: Virtual reality (VR) with head-mounted displays (HMD) may improve medical training and patient care by improving display and integration of different types of information. The aim of this study was to evaluate among different healthcare professions the potential of an interactive and immersive VR environment for liver surgery that integrates all relevant patient data from different sources needed for planning and training of procedures. Methods: 3D-models of the liver, other abdominal organs, vessels, and tumors of a sample patient with multiple hepatic masses were created. 3D-models, clinical patient data, and other imaging data were visualized in a dedicated VR environment with an HMD (IMHOTEP). Users could interact with the data using head movements and a computer mouse. Structures of interest could be selected and viewed individually or grouped. IMHOTEP was evaluated in the context of preoperative planning and training of liver surgery and for the potential of broader surgical application. A standardized questionnaire was voluntarily answered by four groups (students, nurses, resident and attending surgeons). Results: In the evaluation by 158 participants (57 medical students, 35 resident surgeons, 13 attending surgeons and 53 nurses), 89.9% found the VR system agreeable to work with. Participants generally agreed that complex cases in particular could be assessed better (94.3%) and faster (84.8%) with VR than with traditional 2D display methods. The highest potential was seen in student training (87.3%), resident training (84.6%), and clinical routine use (80.3%). Least potential was seen in nursing training (54.8%). Conclusions: The present study demonstrates that using VR with HMD to integrate all available patient data for the preoperative planning of hepatic resections is a viable concept. VR with HMD promises great potential to improve medical training and operation planning and thereby to achieve improvement in patient care. [ABSTRACT FROM AUTHOR]

BACKGROUND: Hypertension treatment guidelines recommend combination therapy with diuretics and other antihypertensive agents, including angiotensin II type 1 (AT1) receptor antagonists. This trial investigated the possibility of pharmacokinetic interactions between the AT1 receptor antagonist olmesartan medoxomil and the thiazide diuretic hydrochlorothiazide in healthy subjects. METHODS: Twenty-four healthy normotensive adult male subjects underwent three consecutive 7-day treatment periods (A, B and C, respectively) during which they were randomised to receive: olmesartan medoxomil 20mg once daily (regimen A), hydrochlorothiazide 25mg once daily (regimen B), or olmesartan medoxomil 20mg once daily plus hydrochlorothiazide 25mg once daily (regimen C). Treatment periods were separated by washouts of 7-14 days. The primary pharmacokinetic parameters evaluated were: the area under the plasma concentration versus time curve at steady state (AUCss,τ), the maximum plasma concentration at steady state (Css,max), and the time at which Css,max occurred (tmax). RESULTS: Complete data sets from 17 subjects were available for pharmacokinetic analyses. Mean concentration versus time profiles were similar for monotherapy and combination treatment for both olmesartan (the active metabolite of olmesartan medoxomil) and hydrochlorothiazide. For olmesartan, comparison of-monotherapy with combination therapy showed that for AUCss,τ and Css,max point-estimates were close to unity, demonstrating bioequivalence. For hydrochlorothiazide, combination therapy resulted in decreases in AUCss,τ and Css,max of approximately 10% versus monotherapy; nevertheless, since 90% CIs were within the acceptance range, bioequivalence was proven. Median tmax values for olmesartan and hydrochlorothiazide for periods A, B and C were identical, indicating bioequivalence. Both olmesartan medoxomil and hydrochlorothiazide were well tolerated. CONCLUSION: These results show that there is little or no potential for a clinically relevant pharmacokinetic interaction between olmesartan medoxomil 20mg and hydrochlorothiazide 25mg, and therefore dosage adjustment should not be necessary when they are co-administered. [ABSTRACT FROM AUTHOR]

Abstract: Immune-mediated heparin-induced thrombocytopenia (HIT) is the clinically most important adverse drug reaction (ADR) in response to heparin therapy characterized by a prothrombotic state despite a decrease in platelet count. We conducted a genome-wide association study in 96 suspected HIT cases and 96 controls to explore the genetic predisposition for HIT within a case-control pharmacovigilance study followed by replication in additional 86 cases and 86 controls from the same study. One single nucleotide polymorphism (SNP, rs1433265, P = 6.5 × 10−5, odds ratio (OR) 2.79) from 16 identified SNPs was successfully replicated (P = 1.5 × 10−4, OR 2.77; combined data set P = 2.7 × 10−8, OR 2.77) and remained the most strongly associated SNP after imputing locus genotypes. Fine mapping revealed a significantly associated risk-conferring haplotype (P = 4.9 × 10−6, OR 2.41). In order to find rare variants contributing to the association signals, we applied a targeted resequencing approach in a subgroup of 73 HIT patients and 23 controls for the regions with the 16 most strongly HIT-associated SNPs. C-alpha testing was applied to test for the impact of rare variants and we detected two candidate genes, the discoidin domain receptor tyrosine kinase 1 (DDR1, P = 3.6 × 10−2) and the multiple C2 and transmembrane domain containing 2 (MCTP2, P = 4.5 × 10−2). For the genes interactor of little elongation complex ELL subunit 1 (ICE1) and a disintegrin-like and metalloproteinase with thrombospondin type 1 motif, 16 (ADAMTS16) nearby rs1433265, we identified several missense variants. Although replication in an independent population is warranted, these findings provide a basis for future studies aiming to identify and characterize genetic susceptibility factors for HIT.Key messages: We identified and validated a HIT-associated locus on chromosome 5.Targeted NGS analysis for rare variants identifies DDR1 and MCTP2 as novel candidates.In addition, missense variants for ADAMTS16 and ICE1 were identified in the locus. [ABSTRACT FROM AUTHOR]

We have studied two different β-peptides in methanol using explicit solvent molecular dynamics simulations and the GROMOS 53A6 force field: a heptapeptide (peptide 1) expected to form a left-handed 314-helix, and a hexapeptide (peptide 2) expected to form a β-hairpin in solution. Our analysis has focused on identifying and analyzing the stability of the dominant secondary structure conformations adopted by the peptides, as well as on comparing the experimental NOE distance upper bounds and 3J-coupling values with their counterparts calculated on the basis of the simulated ensembles. Moreover, we have critically compared the present results with the analogous results obtained with the GROMOS 45A3 (peptide 1) and 43A1 (peptide 2) force fields. We conclude that within the limits of conformational sampling employed here, the GROMOS 53A6 force field satisfactorily reproduces experimental findings regarding the behavior of short β-peptides, with accuracy that is comparable to but not exceeding that of the previous versions of the force field.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]