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Parallel Banking – Frankfurt Can Bring some Light into the Darkness_3
THOMAS SCHÄFER
Inflation and Growth: New Evidence from a Dynamic Panel Threshold Analysis_4
ALEXANDER BICK | STEPHANIE KREMER | DIETER NAUTZ
Who Benefits from Building Insurance Groups?_6
SEBASTIAN SCHLÜTTER | HELMUT GRÜNDL
IT Innovation: Mindfully Resisting the Bandwagon_8
ROMAN BECK | WOLFGANG KÖNIG | IMMANUEL PAHLKE | MARTIN WOLF
“The Part-Time Master in Finance is GBS' Answer to the Bologna Process”_10
UWE WALZ
House of Finance Wins New LOEWE Center_12
Nuclear Magnetic Resonance ("NMR") is a powerful and versatile technique relying on nuclei that posses a spin. Since its discovery more than 6 decades ago, NMR and related techniques has become a tool with innumerable applications throughout the fields of Physics, Chemistry, Biology and Medicine. Numerous Nobel Prizes have been awarded for work in the field and a multi billion dollar industry has developed on its basis.
One of NMR's major shortcomings is its inherent lack of sensitivity. Because it relies on the Boltzmann populations of spin states with a minuscule Zeeman splitting, this is particularly true for room temperature experiments.
As a result, in an enormous technological effort to enlarge the Zeeman splitting NMR magnets have been moving to higher and higher magnetic fields. However, even for proton spins possessing the largest magnetic moment of all nuclei, the degree of polarization that can be achieved in the strongest spectroscopic magnets available today (~24 T) at room temperature is merely ~ 8*(10 exp (-5)). In other words, this low polarization theoretically allows a sensitivity enhancement of 104 towards full polarization.
Since Magnetic Resonance Imaging ("MRI") is based on the same principle, it shares this problem with NMR. Furthermore, for technical and physiological reasons full body MRI tomographs do not reach the magnetic field strengths of spectroscopic NMR magnets, making this even more of an issue for MRI.
In consequence, MRI is chiefly restricted to detecting protons, while both MRI and NMR detection of 13C (or other low nuclei) under physiological conditions, i.e. low natural abundance of 13C and a low concentration of the respective substance, suffer from long acquisitions times that are necessary to obtain adequate signal to noise ratios ("SNR").
However, this drawb of NMR can be overcome. The enormous potential sensitivity increase of four orders of magnitude can - at least partially - be exploited by several hyperpolarization techniques, creating entirely new applications and fields of research.
These hyperpolarization techniques comprise chemical approaches like Parahydrogen Induced Polarization ("PHIP") or Photochemically Induced Dynamic Nuclear Polarization ("Photo-CIDNP"), as well as physical techniques like optically pumped (noble) gases13, 14 or Dynamic Nuclear Polarization ("DNP"), which will be the focus of this work. A hyperpolarized substance will render a larger signal without being physically or chemically altered in any other way. It is therefore "marked" without any marker, making it an agent free contrast agent for MRI.
DNP is a technique, in which hyperpolarization of nuclear spins is achieved by microwave (\MW") irradiation of unpaired electron spins in radicals, which are coupled to these nuclei, e.g. 1H, 13C or 15N. The electron spin population is perturbed if the microwave irradiation is resonant with the electron spin transition, which affects the polarization of hyperfine-coupled close nuclei. For large microwave power (i.e. saturating the electron spin transition) the orders of magnitude larger thermal electron spin polarization is effectively transferred to these nuclear spins in the sample. For proton spins the maximum polarization gain amounts to 660, whereas for 13C the sensitivity gain can be as large as 2600. In contrast to e.g. PHIP, which is restricted to specific reaction precursors, DNP is not limited to specific nuclei or hyperpolarization target molecules, making it a very versatile technique. DNP has been first proposed by Overhauser in 1953,15 and experimentally observed shortly thereafter in metals16 and liquids,17 both being systems with mobile electrons. In the 1960s and 70s, DNP was used as a spectroscopic tool in liquids, thoroughly mapping the effect in the low field regime. As well, several other transfer mechanisms were discovered, which are active in the solid state with localized electrons, namely the solid effect the cross effect and thermal mixing. The theory for all three of these mechanisms predicts reduced transfer efficiencies at higher magnetic fields. This fact and the lack of high frequency microwave sources to excite electron spins at magnetic field strengths above 1 T, effectively relegated DNP to a position of an interesting scientifi curiosity.
In the early 1990s, DNP came to a renaissance, when DNP was performed at high field in solid state magic angle spinning ("MAS") experiments using high power gyrotron microwave sources. This pioneering work sparked a surge of new developments and applications.
As well, this success triggered attempts to investigate also the potential of DNP in the liquid state at high magnetic fields, e.g. at 3.4 T35{38 and 9.2 T. To date, DNP can be considered one of the "hot topics" in the field of magnetic resonance, bringing about special issue in magnetic resonance journals and DNP sections on magnetic resonance conferences.
This thesis deals with the development of an in-bore liquid state DNP polarizer for MRI applications operating in ow through mode at a magnetic field strength of 1.5 T. Following this introductory chapter, the theoretical background necessary to understand and interpret the experimental results is explained in chapter 2. Subsequently, chapter 3 deals with the issue of performing liquid state DNP at high magnetic fields and its challenges. The chapter comprises a quick overview of the necessary hardware, the experimental findings for various samples and the interpretation of these findings. along with the ramifications for the aim of this work. Chapter 4 deals with the issue of increasing sensitivity and contrast in MRI, in particular by means of DNP. The chapter illustrates the development of our polarizer by presenting the hardware that was developed and demonstrating its performance under various conditions. As well, several alternative approaches are introduced and compared to our approach. Finally, chapter 5 summarizes the findings and gives an outlook on further developments.
The main purpose of the Transition Radiation Detector (TRD) located in the central barrel of ALICE (A Large Ion Collider Experiment) is electron identification for separation from pions at momenta pt > 1 GeV/c, since in this momentum range the measurements of the specific energy loss (dE/dx) of the Time Projection Chamber (TPC) is no longer sufficient. Furthermore, it provides a fast trigger for high transverse momentum charged particles (pt > 3 GeV/c) and makes a significant contribution to the optimization of the tracking of reaction products in heavy-ion collisions. Its whole setup comprises 18 supermodules out of which 13 are presently operational and mounted cylindrically around the beam axis of the Large Hadron Collider (LHC). A supermodule contains either 30 or 24 chambers, each consisting of a radiator for transition radiation creation, a drift and an amplifying region followed by the read-out electronics. In total, the TRD is an array of 522 chambers operated with about 28 m3 of a Xe-CO2 [85-15%] gas mixture. During the work of this thesis, the testing, commissioning, operation and maintenance of detector parts, the gas system and its online quality monitor, improvements on the detector control user-interface and studies about a new pre-trigger module for data read-out have been accomplished. The TRD gas system mixes, distributes and circulates the operational gas mixture through the detector. Its overall optimization has been achieved by minimizing gas leakage, surveying, controlling, maintaining and continuously improving it as well as designing and carrying out upgrades. Gas quality monitors of the type \GOOFIE" (Gas prOportional cOunter For drIfting Electrons) can be used in gaseous detectors as on-line monitors of the electron drift velocity, gain and gas properties. One of these devices has been implemented within the TRD gas system, while another one surveys the gas of the TPC. Both devices had to be adapted to the specific needs of the detectors, were under constant surveillance and control, and needed to be further developed on both hardware and software side. To improve the operation of the TRD, modifications on its DCS software (Detector Control System) used for monitoring, controlling, operating, regulating and configuring of hardware and computing devices have been carried out. The DCS is designed to enable an operator to interact with equipment through user interfaces that display the information from the system. The main focus of this work was laid on the optimization of the usability and design of the user interface. The front-end electronics of the TRD require an early start signal (\pre-trigger") from the fast forward detectors or the Time-Of-Flight detector during the running periods. The realization of a new hardware concept for the read-out of the TRD pre-trigger system has been studied and first tests were performed. This new module called PIMDDL (Pre-trigger Interface Module Detector Data Link) is meant to acquire all data necessary to simulate and predict the full pre-trigger functionality, and to verify its proper operation. Furthermore, it shall provide all functionalities of the so-called Control Box Bottom as well as keep the functionalities of the already existing PIM (Pre-trigger Interface Module) in order to combine and replace these two modules in the future.
Grave visitation and concepts of life after death : a comparative study in Frankfurt and Hong Kong
(2012)
Grave visitation is a tradition common to many cultures. Yet, this sensitive topic is rarely addressed in cross cultural comparisons. Why do people visit the graves of their parents? What do they do in the cemetery? Could there be a similar set of intentions behind the diverse customs? By examining the visiting patterns in Frankfurt and Hong Kong, this research is aimed at comparing the concepts of life after death that underlie the practice. Phenomenologically oriented, this is an exploratory study based on qualitative interviews. Integrated with in-depth semi-structure interviewing and thematic analysis, the project covered twelve cases in each city. Research participants were purposefully selected. Data analysis was conducted according to the analytical framework approach. After identifying and clustering of themes, three central and interlocking issues were found: 1. the grave as a new home that connects the living and the dead; 2. death and the interpretation of hope; and 3.intergenerational reciprocity and continuing bonds. Though the images of life after death were ambiguously depicted, grave tending reflected shared expectations of the world beyond. Most significantly, visits to the graves strengthened the ties between the living and the dead, revealing a longing for a continued bond regardless of the forms of burial. At the end, this research illustrated not only the meanings of death but also the notion of religiosity through evaluating the secularisation thesis. Emphasising the dynamics of tradition and personal experience, this contextual reading of current death rituals serves as an original source for religious dialogue and education.
A subgroup of pediatric acute T-lymphoblastic leukemia (T-ALL) was characterized by a gene expression profile comparable to that of early T-cell precursors (ETPs) with a highly unfavorable outcome. We have investigated clinical and molecular characteristics of the ETP-ALL subgroup in adult T-ALL. As ETP-ALL represents a subgroup of early T-ALL we particularly focused on this cohort and identified 178 adult patients enrolled in the German Acute Lymphoblastic Leukemia Multicenter studies (05/93–07/03). Of these, 32% (57/178) were classified as ETP-ALL based on their characteristic immunophenotype. The outcome of adults with ETP-ALL was poor with an overall survival of only 35% at 10 years, comparable to the inferior outcome of early T-ALL with 38%. The molecular characterization of adult ETP-ALL revealed distinct alterations with overexpression of stem cell-related genes (BAALC, IGFBP7, MN1, WT1). Interestingly, we found a low rate of NOTCH1 mutations and no FBXW7 mutations in adult ETP-ALL. In contrast, FLT3 mutations, rare in the overall cohort of T-ALL, were very frequent and nearly exclusively found in ETP-ALL characterized by a specific immunophenotype. These molecular characteristics provide biologic insights and implications with respect to innovative treatment strategies (for example, tyrosine kinase inhibitors) for this high-risk subgroup of adult ETP-ALL.
Optogenetic approaches using light-activated proteins like Channelrhodopsin-2 (ChR2) enable investigating the function of populations of neurons in live Caenorhabditis elegans (and other) animals, as ChR2 expression can be targeted to these cells using specific promoters. Sub-populations of these neurons, or even single cells, can be further addressed by restricting the illumination to the cell of interest. However, this is technically demanding, particularly in free moving animals. Thus, it would be helpful if expression of ChR2 could be restricted to single neurons or neuron pairs, as even wide-field illumination would photostimulate only this particular cell. To this end we adopted the use of Cre or FLP recombinases and conditional ChR2 expression at the intersection of two promoter expression domains, i.e. in the cell of interest only. Success of this method depends on precise knowledge of the individual promoters' expression patterns and on relative expression levels of recombinase and ChR2. A bicistronic expression cassette with GFP helps to identify the correct expression pattern. Here we show specific expression in the AVA reverse command neurons and the aversive polymodal sensory ASH neurons. This approach shall enable to generate strains for optogenetic manipulation of each of the 302 C. elegans neurons. This may eventually allow to model the C. elegans nervous system in its entirety, based on functional data for each neuron.
Spinocerebellar Ataxia Type 2 (SCA2) is caused by expansion of a polyglutamine encoding triplet repeat in the human ATXN2 gene beyond (CAG)31. This is thought to mediate toxic gain-of-function by protein aggregation and to affect RNA processing, resulting in degenerative processes affecting preferentially cerebellar neurons. As a faithful animal model, we generated a knock-in mouse replacing the single CAG of murine Atxn2 with CAG42, a frequent patient genotype. This expansion size was inherited stably. The mice showed phenotypes with reduced weight and later motor incoordination. Although brain Atxn2 mRNA became elevated, soluble ATXN2 protein levels diminished over time, which might explain partial loss-of-function effects. Deficits in soluble ATXN2 protein correlated with the appearance of insoluble ATXN2, a progressive feature in cerebellum possibly reflecting toxic gains-of-function. Since in vitro ATXN2 overexpression was known to reduce levels of its protein interactor PABPC1, we studied expansion effects on PABPC1. In cortex, PABPC1 transcript and soluble and insoluble protein levels were increased. In the more vulnerable cerebellum, the progressive insolubility of PABPC1 was accompanied by decreased soluble protein levels, with PABPC1 mRNA showing no compensatory increase. The sequestration of PABPC1 into insolubility by ATXN2 function gains was validated in human cell culture. To understand consequences on mRNA processing, transcriptome profiles at medium and old age in three different tissues were studied and demonstrated a selective induction of Fbxw8 in the old cerebellum. Fbxw8 is encoded next to the Atxn2 locus and was shown in vitro to decrease the level of expanded insoluble ATXN2 protein. In conclusion, our data support the concept that expanded ATXN2 undergoes progressive insolubility and affects PABPC1 by a toxic gain-of-function mechanism with tissuespecific effects, which may be partially alleviated by the induction of FBXW8.
Background: Acoustic Radiation Force Impulse (ARFI)-imaging is an ultrasound-based elastography method enabling quantitative measurement of tissue stiffness. The aim of the present study was to evaluate sensitivity and specificity of ARFI-imaging for differentiation of thyroid nodules and to compare it to the well evaluated qualitative real-time elastography (RTE).
Methods: ARFI-imaging involves the mechanical excitation of tissue using acoustic pulses to generate localized displacements resulting in shear-wave propagation which is tracked using correlation-based methods and recorded in m/s. Inclusion criteria were: nodules $5 mm, and cytological/histological assessment. All patients received conventional ultrasound, real-time elastography (RTE) and ARFI-imaging.
Results: One-hundred-fifty-eight nodules in 138 patients were available for analysis. One-hundred-thirty-seven nodules were benign on cytology/histology, and twenty-one nodules were malignant. The median velocity of ARFI-imaging in the healthy thyroid tissue, as well as in benign and malignant thyroid nodules was 1.76 m/s, 1.90 m/s, and 2.69 m/s, respectively. While no significant difference in median velocity was found between healthy thyroid tissue and benign thyroid nodules, a significant difference was found between malignant thyroid nodules on the one hand and healthy thyroid tissue (p = 0.0019) or benign thyroid nodules (p = 0.0039) on the other hand. No significant difference of diagnostic accuracy for the diagnosis of malignant thyroid nodules was found between RTE and ARFI-imaging (0.74 vs. 0.69, p = 0.54). The combination of RTE with ARFI did not improve diagnostic accuracy.
Conclusions: ARFI can be used as an additional tool in the diagnostic work up of thyroid nodules with high negative predictive value and comparable results to RTE.
Purpose: To investigate the prognostic value of survivin expression in pretreatment specimens from patients with anal cancer treated with concurrent 5-FU and mitomycin C-based chemoradiation (CRT).
Material and methods: Immunohistochemical staining for survivin was performed in pretreatment biopsies of 62 patients with anal carcinoma. Survivin expression was correlated with clinical and histopathological characteristics as well as local failure free- (LFFS), distant metastases free- (DMFS), cancer specific- (CSS), and overall survival (OS).
Results: Survivin staining intensity was weak in 10%, intermediate in 48% and intense in 42% of the patients. No association between survivin expression and clinicopathologic factors (tumor stage, age and HIV status) could be shown. In univariate analysis, the level of survivin staining was significantly correlated with DMFS (low survivin vs. high survivin: 94% vs. 74%, p=0.04). T-stage, N-stage and the tumor grading were significantly associated with OS and CSS and with DMFS and LFFS, respectively. In multivariate analysis, survivin was confirmed as independent prognostic parameter for DMFS (RR, 0.04; p=0.02) and for OS (RR, 0.27; p=0.04).
Conclusion: Our results demonstrated that the level of pretreatment survivin is correlated with the clinical outcome in patients with anal carcinoma treated with concurrent CRT. Further studies are warranted to elucidate the complex role of survivin for the oncologic treatment and to exploit the protein as a therapeutic target in combined modality treatment of anal cancer.
In the title molecule, C18H17N5O2, the dihedral angle between the benzene plane and the benzimidazole plane is 19.8 (1)° and the angle between the benzene plane and the triazole plane is 16.7 (1)°. In the crystal, molecules are connected by O—H[cdots, three dots, centered]N hydrogen bonds, forming zigzag chains along the c-axis direction. The chains are connected by bifurcated N—H[cdots, three dots, centered](N,N) hydrogen bonds into layers parallel to (100). These layers are connected along the a-axis direction by weak C—H[cdots, three dots, centered]O contacts, forming a three-dimensional network.
SHARPIN (SHANK-associated RH domain interacting protein) is part of a large multi-protein E3 ubiquitin ligase complex called LUBAC (linear ubiquitin chain assembly complex), which catalyzes the formation of linear ubiquitin chains and regulates immune and apoptopic signaling pathways. The C-terminal half of SHARPIN contains ubiquitin-like domain and Npl4-zinc finger domains that mediate the interaction with the LUBAC subunit HOIP and ubiquitin, respectively. In contrast, the N-terminal region does not show any homology with known protein interaction domains but has been suggested to be responsible for self-association of SHARPIN, presumably via a coiled-coil region. We have determined the crystal structure of the N-terminal portion of SHARPIN, which adopts the highly conserved pleckstrin homology superfold that is often used as a scaffold to create protein interaction modules. We show that in SHARPIN, this domain does not appear to be used as a ligand recognition domain because it lacks many of the surface properties that are present in other pleckstrin homology fold-based interaction modules. Instead, it acts as a dimerization module extending the functional applications of this superfold.
Tumor progression and pregnancy share many common features, such as immune tolerance and invasion. The invasion of trophoblasts in the placenta into the uterine wall is essential for fetal development, and is thus precisely regulated. Its deregulation has been implicated in preeclampsia, a leading cause for maternal and perinatal mortality and morbidity. Pathogenesis of preeclampsia remains to be defined. Microarray-based gene profiling has been widely used for identifying genes responsible for preeclampsia. In this review, we have summarized the recent data from the microarray studies with preeclamptic placentas. Despite the complex of gene signatures, suggestive of the heterogeneity of preeclampsia, these studies identified a number of differentially expressed genes associated with preeclampsia. Interestingly, most of them have been reported to be tightly involved in tumor progression. We have discussed these interesting genes and analyzed their potential molecular functions in preeclampsia, compared with their roles in malignancy development. Further investigations are warranted to explore the involvement in molecular network of each identified gene, which may provide not only novel strategies for prevention and therapy for preeclampsia but also a better understanding of cancer cells. The trophoblastic cells, with their capacity for proliferation and differentiation, apoptosis and survival, migration, angiogenesis and immune modulation by exploiting similar molecular pathways, make them a compelling model for cancer research.
Activation of TRPC6 channels is essential for lung ischaemia–reperfusion induced oedema in mice
(2012)
Lung ischaemia–reperfusion-induced oedema (LIRE) is a life-threatening condition that causes pulmonary oedema induced by endothelial dysfunction. Here we show that lungs from mice lacking nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox2y/−) or the classical transient receptor potential channel 6 (TRPC6−/−) are protected from LIR-induced oedema (LIRE). Generation of chimeric mice by bone marrow cell transplantation and endothelial-specific Nox2 deletion showed that endothelial Nox2, but not leukocytic Nox2 or TRPC6, are responsible for LIRE. Lung endothelial cells from Nox2- or TRPC6-deficient mice showed attenuated ischaemia-induced Ca2+ influx, cellular shape changes and impaired barrier function. Production of reactive oxygen species was completely abolished in Nox2y/− cells. A novel mechanistic model comprising endothelial Nox2-derived production of superoxide, activation of phospholipase C-γ, inhibition of diacylglycerol (DAG) kinase, DAG-mediated activation of TRPC6 and ensuing LIRE is supported by pharmacological and molecular evidence. This mechanism highlights novel pharmacological targets for the treatment of LIRE.
A decade since the availability of Mycobacterium tuberculosis (Mtb) genome sequence, no promising drug has seen the light of the day. This not only indicates the challenges in discovering new drugs but also suggests a gap in our current understanding of Mtb biology. We attempt to bridge this gap by carrying out extensive re-annotation and constructing a systems level protein interaction map of Mtb with an objective of finding novel drug target candidates. Towards this, we synergized crowd sourcing and social networking methods through an initiative ‘Connect to Decode’ (C2D) to generate the first and largest manually curated interactome of Mtb termed ‘interactome pathway’ (IPW), encompassing a total of 1434 proteins connected through 2575 functional relationships. Interactions leading to gene regulation, signal transduction, metabolism, structural complex formation have been catalogued. In the process, we have functionally annotated 87% of the Mtb genome in context of gene products. We further combine IPW with STRING based network to report central proteins, which may be assessed as potential drug targets for development of drugs with least possible side effects. The fact that five of the 17 predicted drug targets are already experimentally validated either genetically or biochemically lends credence to our unique approach.
Even in V1, where neurons have well characterized classical receptive fields (CRFs), it has been difficult to deduce which features of natural scenes stimuli they actually respond to. Forward models based upon CRF stimuli have had limited success in predicting the response of V1 neurons to natural scenes. As natural scenes exhibit complex spatial and temporal correlations, this could be due to surround effects that modulate the sensitivity of the CRF. Here, instead of attempting a forward model, we quantify the importance of the natural scenes surround for awake macaque monkeys by modeling it non-parametrically. We also quantify the influence of two forms of trial to trial variability. The first is related to the neuron’s own spike history. The second is related to ongoing mean field population activity reflected by the local field potential (LFP). We find that the surround produces strong temporal modulations in the firing rate that can be both suppressive and facilitative. Further, the LFP is found to induce a precise timing in spikes, which tend to be temporally localized on sharp LFP transients in the gamma frequency range. Using the pseudo R2 as a measure of model fit, we find that during natural scene viewing the CRF dominates, accounting for 60% of the fit, but that taken collectively the surround, spike history and LFP are almost as important, accounting for 40%. However, overall only a small proportion of V1 spiking statistics could be explained (R2~5%), even when the full stimulus, spike history and LFP were taken into account. This suggests that under natural scene conditions, the dominant influence on V1 neurons is not the stimulus, nor the mean field dynamics of the LFP, but the complex, incoherent dynamics of the network in which neurons are embedded.
Previous PET and MRI studies have indicated that the degree to which pathology translates into clinical symptoms is strongly dependent on sex with women more likely to express pathology as a diagnosis of AD, whereas men are more resistant to clinical symptoms in the face of the same degree of pathology. Here we use DTI to investigate the difference between male and female white matter tracts in healthy older participants (24 women, 16 men) and participants with mild cognitive impairment (21 women, 12 men). Differences between control and MCI participants were found in fractional anisotropy (FA), radial diffusion (DR), axial diffusion (DA) and mean diffusion (MD). A significant main effect of sex was also reported for FA, MD and DR indices, with male control and male MCI participants having significantly more microstructural damage than their female counterparts. There was no sex by diagnosis interaction. Male MCIs also had significantly less normalised grey matter (GM) volume than female MCIs. However, in terms of absolute brain volume, male controls had significantly more brain volume than female controls. Normalised GM and WM volumes were found to decrease significantly with age with no age by sex interaction. Overall, these data suggest that the same degree of cognitive impairment is associated with greater structural damage in men compared with women.
Background: In patients with genotype 1 chronic hepatitis C infection, telaprevir (TVR) in combination with peginterferon and ribavirin (PR) significantly increased sustained virologic response (SVR) rates compared with PR alone. However, genotypic changes could be observed in TVR-treated patients who did not achieve an SVR.
Methods: Population sequence analysis of the NS3•4A region was performed in patients who did not achieve SVR with TVR-based treatment.
Results: Resistant variants were observed after treatment with a telaprevir-based regimen in 12% of treatment-naïve patients (ADVANCE; T12PR arm), 6% of prior relapsers, 24% of prior partial responders, and 51% of prior null responder patients (REALIZE, T12PR48 arms). NS3 protease variants V36M, R155K, and V36M+R155K emerged frequently in patients with genotype 1a and V36A, T54A, and A156S/T in patients with genotype 1b. Lower-level resistance to telaprevir was conferred by V36A/M, T54A/S, R155K/T, and A156S variants; and higher-level resistance to telaprevir was conferred by A156T and V36M+R155K variants. Virologic failure during telaprevir treatment was more common in patients with genotype 1a and in prior PR nonresponder patients and was associated with higher-level telaprevir-resistant variants. Relapse was usually associated with wild-type or lower-level resistant variants. After treatment, viral populations were wild-type with a median time of 10 months for genotype 1a and 3 weeks for genotype 1b patients.
Conclusions: A consistent, subtype-dependent resistance profile was observed in patients who did not achieve an SVR with telaprevir-based treatment. The primary role of TVR is to inhibit wild-type virus and variants with lower-levels of resistance to telaprevir. The complementary role of PR is to clear any remaining telaprevir-resistant variants, especially higher-level telaprevir-resistant variants. Resistant variants are detectable in most patients who fail to achieve SVR, but their levels decline over time after treatment.
In the title compound, C27H37N2 +·Cl−·2CH2Cl2, the cation and the anion are each located on a crystallographic mirror plane. Both of the dichloromethane solvent molecules show a disorder across a mirror plane over two equally occupied positions. Additionally, one isopropyl group is also disordered. In the crystal, the cations are connected to the chloride ions via C—H[cdots, three dots, centered]Cl hydrogen bonds.
In the title compound, C27H37N2 +·Br−·2CH2Cl2, both the cation and the anion are located on a crystallographic mirror plane. Both of the dichloromethane solvent molecules show a disorder across a mirror plane over two equally occupied positions. In the crystal, the cations are connnected to the bromide ions via C—H[cdots, three dots, centered]Br hydrogen bonds.
Molecules of the title compound (alternative name: butane-1,4-diyl dinicotinate), C16H16N2O4, lie on a inversion centre, located at the mid-point of the central C—C bond of the aliphatic chain, giving one half-molecule per asymmetric unit. The butane chain adopts an all-trans conformation. The dihedral angle between the mean plane of the butane-3-carboxylate group [for the non-H atoms, maximum deviation = 0.0871 (15) Å] and the pyridine ring is 10.83 (7)°. In the crystal, molecules lie in planes parallel to (122). The structure features weak π–π interactions with a centroid–centroid distance of 3.9281 (11) Å.
The crystal structure of the title compound, [Fe(C5H5)(CH3CN)(CO)2]BF4, of which only the coordinates of the non-H atoms of the cation have previously been reported [Fadel et al. (1979 [triangle]). Z. Anorg. Allg. Chem. 453, 98–106] has been redetermined. The FeII atom in the complex cation is coordinated by a cyclopentadienyl ring, two carbonyl ligands and an acetonitrile molecule displaying a three-legged piano stool structure. Three of the four F atoms of the BF4 − anion are disordered over two sets of sites, with a site-occupancy factor of 0.709 (10) for the major occupied site.
A new polymorph of the title compound, [Pd2(C8H18P)2(C8H19P)2], has been found. It belongs to the triclinic P-1 space group, whereas the known form [Leoni, Sommovigo, Pasquali, Sabatino & Braga (1992 [triangle]), J. Organomet. Chem. 423, 263–270] crystallizes in the monoclinic C2/c space group. The title compound features a dinuclear palladium complex with a planar central Pd2(μ-P)2 core (r.m.s. deviation = 0.003 Å). The Pd—Pd distance of 2.5988 (5) Å is within the range of a PdI—PdI bond. The molecules of both polymorphs are located on a crystallographic centre of inversion. The molecular conformations of the two polymorphs are essentially identical. The crystal packing patterns, on the other hand, are slightly different.
Introduction: Acute kidney injury (AKI) after cardiac surgery increases length of hospital stay and in-hospital mortality. A significant number of patients undergoing cardiac surgical procedures require perioperative intra-aortic balloon pump (IABP) support. Use of an IABP has been linked to an increased incidence of perioperative renal dysfunction and death. This might be due to dislodgement of atherosclerotic material in the descending thoracic aorta (DTA). Therefore, we retrospectively studied the correlation between DTA atheroma, AKI and in-hospital mortality.
Methods: A total of 454 patients were retrospectively matched to one of four groups: -IABP/-DTA atheroma, +IABP/-DTA atheroma, -IABP/+DTA atheroma, +IABP/+DTA atheroma. Patients were then matched according to presence/absence of DTA atheroma, presence/absence of IABP, performed surgical procedure, age, gender and left ventricular ejection fraction (LVEF). DTA atheroma was assessed through standard transesophageal echocardiography (TEE) imaging studies of the descending thoracic aorta.
Results: Basic patient characteristics, except for age and gender, did not differ between groups. Perioperative AKI in patients with -DTA atheroma/+IABP was 5.1% versus 1.7% in patients with -DTA atheroma/-IABP. In patients with +DTA atheroma/+IABP the incidence of AKI was 12.6% versus 5.1% in patients with +DTA atheroma/-IABP. In-hospital mortality in patients with +DTA atheroma/-IABP was 3.4% versus 8.4% with +DTA atheroma/+IABP. In patients with +DTA atheroma/+IABP in hospital mortality was 20.2% versus 6.4% with +DTA atheroma/-IABP. Multivariate logistic regression identified DTA atheroma > 1 mm (P = *0.002, odds ratio (OR) = 4.13, confidence interval (CI) = 1.66 to 10.30), as well as IABP support (P = *0.015, OR = 3.04, CI = 1.24 to 7.45) as independent predictors of perioperative AKI and increased in-hospital mortality. DTA atheroma in conjunction with IABP significantly increased the risk of developing acute kidney injury (P = 0.0016) and in-hospital mortality (P = 0.0001) when compared to control subjects without IABP and without DTA atheroma.
Conclusions: Perioperative IABP and DTA atheroma are independent predictors of perioperative AKI and in-hospital mortality. Whether adding an IABP in patients with severe DTA calcification increases their risk of developing AKI and mortality postoperatively cannot be clearly answered in this study. Nevertheless, when IABP and DTA are combined, patients are more likely to develop AKI and to die postoperatively in comparison to patients without IABP and DTA atheroma.
Introduction: In order to assess the significance of drug levels measured in intensive care medicine, clinical and forensic toxicology, as well as for therapeutic drug monitoring, it is essential that a comprehensive collection of data is readily available. Therefore, it makes sense to offer a carefully referenced compilation of therapeutic and toxic plasma concentration ranges, as well as half-lives, of a large number of drugs and other xenobiotics for quick and comprehensive information.
Methods: Data have been abstracted from original papers and text books, as well as from previous compilations, and have been completed with data collected in our own forensic and clinical toxicology laboratory. The data presented in the table and corresponding annotations have been developed over the past 20 years and longer. A previous compilation has been completely revised and updated. In addition, more than 170 substances, especially drugs that have been introduced to the market since 2003 as well as illegal drugs, which became known to cause intoxications, were added. All data were carefully referenced and more than 200 new references were included. Moreover, the annotations providing details were completely revised and more than 100 annotations were added.
Results: For nearly 1,000 drugs and other xenobiotics, therapeutic ("normal") and, if data were available, toxic and comatose-fatal blood-plasma concentrations and elimination half-lives were compiled in a table.
Conclusions: In case of intoxications, the concentration of the ingested substances and/or metabolites in blood plasma better predicts the clinical severity of the case when compared to the assumed amount and time of ingestion. Comparing and contrasting the clinical case against the data provided, including the half-life, may support the decision for or against further intensive care. In addition, the data provided are useful for the therapeutic monitoring of pharmacotherapies, to facilitate the diagnostic assessment and monitoring of acute and chronic intoxications, and to support forensic and clinical expert opinions.
Expansions of the polyglutamine (polyQ) domain (≥34) in Ataxin-2 (ATXN2) are the primary cause of spinocerebellar ataxia type 2 (SCA2). Recent studies reported that intermediate-length (27–33) expansions increase the risk of Amyotrophic Lateral Sclerosis (ALS) in 1–4% of cases in diverse populations. This study investigates the Turkish population with respect to ALS risk, genotyping 158 sporadic, 78 familial patients and 420 neurologically healthy controls. We re-assessed the effect of ATXN2 expansions and extended the analysis for the first time to cover the ATXN2 locus with 18 Single Nucleotide Polymorphisms (SNPs) and their haplotypes. In accordance with other studies, our results confirmed that 31–32 polyQ repeats in the ATXN2 gene are associated with risk of developing ALS in 1.7% of the Turkish ALS cohort (p = 0.0172). Additionally, a significant association of a 136 kb haplotype block across the ATXN2 and SH2B3 genes was found in 19.4% of a subset of our ALS cohort and in 10.1% of the controls (p = 0.0057, OR: 2.23). ATXN2 and SH2B3 encode proteins that both interact with growth receptor tyrosine kinases. Our novel observations suggest that genotyping of SNPs at this locus may be useful for the study of ALS risk in a high percentage of individuals and that ATXN2 and SH2B3 variants may interact in modulating the disease pathway.
The neural correlates of developmental dyslexia have been investigated intensively over the last two decades and reliable evidence for a dysfunction of left-hemispheric reading systems in dyslexic readers has been found in functional neuroimaging studies. In addition, structural imaging studies using voxel-based morphometry (VBM) demonstrated grey matter reductions in dyslexics in several brain regions. To objectively assess the consistency of these findings, we performed activation likelihood estimation (ALE) meta-analysis on nine published VBM studies reporting 62 foci of grey matter reduction in dyslexic readers. We found six significant clusters of convergence in bilateral temporo-parietal and left occipito-temporal cortical regions and in the cerebellum bilaterally. To identify possible overlaps between structural and functional deviations in dyslexic readers, we conducted additional ALE meta-analyses of imaging studies reporting functional underactivations (125 foci from 24 studies) or overactivations (95 foci from 11 studies ) in dyslexics. Subsequent conjunction analyses revealed overlaps between the results of the VBM meta-analysis and the meta-analysis of functional underactivations in the fusiform and supramarginal gyri of the left hemisphere. An overlap between VBM results and the meta-analysis of functional overactivations was found in the left cerebellum. The results of our study provide evidence for consistent grey matter variations bilaterally in the dyslexic brain and substantial overlap of these structural variations with functional abnormalities in left hemispheric regions.
We describe and analyze a Neandertal postcranial skeleton and dentition, which together show unambiguous signs of right-handedness. Asymmetries between the left and right upper arm in Regourdou 1 were identified nearly 20 years ago, then confirmed by more detailed analyses of the inner bone structure for the clavicle, humerus, radius and ulna. The total pattern of all bones in the shoulder and arm reveals that Regourdou 1 was a right-hander. Confirmatory evidence comes from the mandibular incisors, which display a distinct pattern of right oblique scratches, typical of right-handed manipulations performed at the front of the mouth. Regourdou's right handedness is consistent with the strong pattern of manual lateralization in Neandertals and further confirms a modern pattern of left brain dominance, presumably signally linguistic competence. These observations along with cultural, genetic and morphological evidence indicate language competence in Neandertals and their European precursors.
Visual perception is highly variable and can be influenced by the surrounding world. Previous research has revealed that body perception can be biased due to adaptation to thin or fat body shapes. The aim of the present study was to show that adaptation to certain body shapes and the resulting perceptual biases transfer across different identities of adaptation and test stimuli. We designed two similar adaptation experiments in which healthy female participants adapted to pictures of either thin or fat bodies and subsequently compared more or less distorted pictures of their own body to their actual body shape. In the first experiment (n = 16) the same identity was used as adaptation and test stimuli (i.e. pictures of the participant’s own body) while in the second experiment (n = 16) we used pictures of unfamiliar thin or fat bodies as adaptation stimuli. We found comparable adaptation effects in both experiments: After adaptation to a thin body, participants rated a thinner than actual body picture to be the most realistic and vice versa. We therefore assume that adaptation to certain body shapes transfers across different identities. These results raise the questions of whether some type of natural adaptation occurs in everyday life. Natural and predominant exposure to certain bodily features like body shape – especially the thin ideal in Western societies – could bias perception for these features. In this regard, further research might shed light on aspects of body dissatisfaction and the development of body image disturbances in terms of eating disorders.
The theoretical basis for the link between the leaf exchange of carbonyl sulfide (COS), carbon dioxide (CO2) and water vapour (H2O) and the assumptions that need to be made in order to use COS as a tracer for canopy net photosynthesis, transpiration and stomatal conductance, are reviewed. The ratios of COS to CO2 and H2O deposition velocities used to this end are shown to vary with the ratio of the internal to ambient CO2 and H2O mole fractions and the relative limitations by boundary layer, stomatal and internal conductance for COS. It is suggested that these deposition velocity ratios exhibit considerable variability, a finding that challenges current parameterizations, which treat these as vegetation-specific constants. COS is shown to represent a better tracer for CO2 than H2O. Using COS as a tracer for stomatal conductance is hampered by our present poor understanding of the leaf internal conductance to COS. Estimating canopy level CO2 and H2O fluxes requires disentangling leaf COS exchange from other ecosystem sources/sinks of COS. We conclude that future priorities for COS research should be to improve the quantitative understanding of the variability in the ratios of COS to CO2 and H2O deposition velocities and the controlling factors, and to develop operational methods for disentangling ecosystem COS exchange into contributions by leaves and other sources/sinks. To this end, integrated studies, which concurrently quantify the ecosystem-scale CO2, H2O and COS exchange and the corresponding component fluxes, are urgently needed.
We investigate the potential of carbonyl sulfide (COS) for being used as a tracer for canopy net photosynthesis, transpiration and stomatal conductance by examining the theoretical basis of the link between leaf COS, carbon dioxide (CO2) and water vapour (H2O) exchange. Our analysis identifies several limitations that need to be overcome to this end, however at present we lack appropriate ecosystem-scale field measurements for assessing their practical significance. It however appears that COS represents a better tracer for CO2 than H2O. Concurrent measurements of ecosystem scale COS, CO2 and H2O exchange are advocated.
This paper examines data on financial sophistication among the U.S. older population, using a special-purpose module implemented in the Health and Retirement Study. We show that financial sophistication is deficient for older respondents (aged 55+). Specifically, many in this group lack a basic grasp of asset pricing, risk diversification, portfolio choice, and investment fees. Subpopulations with particular deficits include women, the least educated, persons over the age of 75, and non-Whites. In view of the fact that people are increasingly being asked to take on responsibility for their own retirement security, such lack of knowledge can have serious implications.
This paper studies constrained portfolio problems that may involve constraints on the probability or the expected size of a shortfall of wealth or consumption. Our first contribution is that we solve the problems by dynamic programming, which is in contrast to the existing literature that applies the martingale method. More precisely, we construct the non-separable value function by formalizing the optimal constrained terminal wealth to be a (conjectured) contingent claim on the optimal non-constrained terminal wealth. This is relevant by itself, but also opens up the opportunity to derive new solutions to constrained problems. As a second contribution, we thus derive new results for non-strict constraints on the shortfall of inter¬mediate wealth and/or consumption.
Background: With increasing numbers of lamellar keratoplasties, eye banks are challenged to deliver precut lamellar donor tissue. In Europe, the most common technique of corneal storage is organ culture which requires a deswelling process before surgical processing. The aim of this study was to investigate the influence of different deswelling times on the cutting plane quality after microkeratome-assisted lamellar dissection.
Methods: Eight paired donor corneas (16 specimens) not suitable for transplantation were organ cultured under standard conditions at the Eye Bank of the Ludwig-Maximilians Universität, Munich, Germany. Pairs of corneal buttons were analyzed during the deswelling process in dextrane-containing medium. While one cornea was cut at an early time point during the deswelling process and put back into deswelling medium thereafter, the partner cornea was completely deswollen and dissected after 72 hours. Specimens were then further processed for scanning electron microscopy. Surface quality was assessed both digitally using Scanning Probe Imaging Processing software, and manually by three blinded graders.
Results: The corneal buttons processed at the beginning of the deswelling process had a smoother surface when compared to the partner cornea that was cut at the end of the deswelling process. In our setting, no relevant difference was detectable between manual and automated microkeratome dissection.
Conclusion: For lamellar keratoplasty, organ-cultured corneas should be processed at an early stage during the deswelling process. We interpret the smoother dissection plane during early deswelling as a result of mechanical properties in a highly hydrated cornea.
Background: Cyanobacteria possess several cytochrome P450s, but very little is known about their catalytic functions. CYP110 genes unique to cyanaobacteria are widely distributed in heterocyst-forming cyanobacteria including nitrogen-fixing genera Nostoc and Anabaena. We screened the biocatalytic functions of all P450s from three cyanobacterial strains of genus Nostoc or Anabaena using a series of small molecules that contain flavonoids, sesquiterpenes, low-molecular-weight drugs, and other aromatic compounds.
Results: Escherichia coli cells carrying each P450 gene that was inserted into the pRED vector, containing the RhFRed reductase domain sequence from Rhodococcus sp. NCIMB 9784 P450RhF (CYP116B2), were co-cultured with substrates and products were identified when bioconversion reactions proceeded. Consequently, CYP110E1 of Nostoc sp. strain PCC 7120, located in close proximity to the first branch point in the phylogenetic tree of the CYP110 family, was found to be promiscuous for the substrate range mediating the biotransformation of various small molecules. Naringenin and (hydroxyl) flavanones were respectively converted to apigenin and (hydroxyl) flavones, by functioning as a flavone synthase. Such an activity is reported for the first time in prokaryotic P450s. Additionally, CYP110E1 biotransformed the notable sesquiterpene zerumbone, anti-inflammatory drugs ibuprofen and flurbiprofen (methylester forms), and some aryl compounds such as 1-methoxy and 1-ethoxy naphthalene to produce hydroxylated compounds that are difficult to synthesize chemically, including novel compounds.
Conclusion: We elucidated that the CYP110E1 gene, C-terminally fused to the P450RhF RhFRed reductase domain sequence, is functionally expressed in E. coli to synthesize a robust monooxygenase, which shows promiscuous substrate specificity (affinity) for various small molecules, allowing the biosynthesis of not only flavones (from flavanones) but also a variety of hydroxyl-small molecules that may span pharmaceutical and nutraceutical industries.
The biosynthesis pathway to diadinoxanthin and fucoxanthin was elucidated in Phaeodactylum tricornutum by a combined approach involving metabolite analysis identification of gene function. For the initial steps leading to β-carotene, putative genes were selected from the genomic database and the function of several of them identified by genetic pathway complementation in Escherichia coli. They included genes encoding a phytoene synthase, a phytoene desaturase, a ζ-carotene desaturase, and a lycopene β-cyclase. Intermediates of the pathway beyond β-carotene, present in trace amounts, were separated by TLC and identified as violaxanthin and neoxanthin in the enriched fraction. Neoxanthin is a branching point for the synthesis of both diadinoxanthin and fucoxanthin and the mechanisms for their formation were proposed. A single isomerization of one of the allenic double bounds in neoxanthin yields diadinoxanhin. Two reactions, hydroxylation at C8 in combination with a keto-enol tautomerization and acetylation of the 3′-HO group results in the formation of fucoxanthin.
Chronic kidney disease (CKD) is an important cause of morbidity and mortality in HIV-positive individuals. Hepatitis C (HCV) co-infection has been associated with increased risk of CKD, but prior studies lack information on potential mechanisms. We evaluated the association between HCV or hepatitis B (HBV) co-infection and progressive CKD among 3,441 antiretroviral-treated clinical trial participants. Progressive CKD was defined as the composite of end-stage renal disease, renal death, or significant glomerular filtration rate (eGFR) decline (25% decline to eGFR <60 mL/min/1.73 m2 or 25% decline with a baseline <60). Generalized Estimating Equations were used to model the odds of progressive CKD. At baseline, 13.8% and 3.3% of participants were co-infected with HCV and HBV, respectively. Median eGFR was 111, and 3.7% developed progressive CKD. After adjustment, the odds of progressive CKD were increased in participants with HCV (OR 1.72, 95% CI 1.07–2.76) or HBV (OR 2.26, 95% CI 1.15–4.44). Participants with undetectable or low HCV-RNA had similar odds of progressive CKD as HCV seronegative participants, while participants with HCV-RNA >800,000 IU/ml had increased odds (OR 3.07; 95% CI 1.60–5.90). Interleukin-6, hyaluronic acid, and the FIB-4 hepatic fibrosis index were higher among participants who developed progressive CKD, but were no longer associated with progressive CKD after adjustment. Future studies should validate the relationship between HCV viremia and CKD.
Background: To perform a comprehensive study on the relationship between vitamin D metabolism and the response to interferon-α-based therapy of chronic hepatitis C.
Methodology/Principal Findings: Associations between a functionally relevant polymorphism in the gene encoding the vitamin D 1α-hydroxylase (CYP27B1-1260 rs10877012) and the response to treatment with pegylated interferon-α (PEG-IFN-α) and ribavirin were determined in 701 patients with chronic hepatitis C. In addition, associations between serum concentrations of 25-hydroxyvitamin D3 (25[OH]D3) and treatment outcome were analysed. CYP27B1-1260 rs10877012 was found to be an independent predictor of sustained virologic response (SVR) in patients with poor-response IL28B genotypes (15% difference in SVR for rs10877012 genotype AA vs. CC, p = 0.02, OR = 1.52, 95% CI = 1.061–2.188), but not in patients with favourable IL28B genotype. Patients with chronic hepatitis C showed a high prevalence of vitamin D insufficiency (25[OH]D3<20 ng/mL) during all seasons, but 25(OH)D3 serum levels were not associated with treatment outcome.
Conclusions/Significance: Our study suggests a role of bioactive vitamin D (1,25[OH]2D3, calcitriol) in the response to treatment of chronic hepatitis C. However, serum concentration of the calcitriol precursor 25(OH)D3 is not a suitable predictor of treatment outcome.
Amino acids can induce yeast cell adhesion but how amino acids are sensed and signal the modulation of the FLO adhesion genes is not clear. We discovered that the budding yeast Saccharomyces cerevisiae CEN.PK evolved invasive growth ability under prolonged nitrogen limitation. Such invasive mutants were used to identify amino acid transporters as regulators of FLO11 and invasive growth. One invasive mutant had elevated levels of FLO11 mRNA and a Q320STOP mutation in the SFL1 gene that encodes a protein kinase A pathway regulated repressor of FLO11. Glutamine-transporter genes DIP5 and GNP1 were essential for FLO11 expression, invasive growth and biofilm formation in this mutant. Invasive growth relied on known regulators of FLO11 and the Ssy1-Ptr3-Ssy5 complex that controls DIP5 and GNP1, suggesting that Dip5 and Gnp1 operates downstream of the Ssy1-Ptr3-Ssy5 complex for regulation of FLO11 expression in a protein kinase A dependent manner. The role of Dip5 and Gnp1 appears to be conserved in the S. cerevisiae strain ∑1278b since the dip5 gnp1 ∑1278b mutant showed no invasive phenotype.
Secondly, the amino acid transporter gene GAP1 was found to influence invasive growth through FLO11 as well as other FLO genes. Cells carrying a dominant loss-of-function PTR3647::CWNKNPLSSIN allele had increased transcription of the adhesion genes FLO1, 5, 9, 10, 11 and the amino acid transporter gene GAP1. Deletion of GAP1 caused loss of FLO11 expression and invasive growth. However, deletions of FLO11 and genes encoding components of the mitogen-activated protein kinase pathway or the protein kinase A pathway were not sufficient to abolish invasive growth, suggesting involvement of other FLO genes and alternative pathways. Increased intracellular amino acid pools in the PTR3647::CWNKNPLSSIN-containing strain opens the possibility that Gap1 regulates the FLO genes through alteration of the amino acid pool sizes.
Background and Aims: The prevalence of hepatitis C virus (HCV) antibodies in Germany has been estimated to be in the range of 0.4–0.63%. Screening for HCV is recommended in patients with elevated ALT levels or significant risk factors for HCV transmission only. However, 15–30% of patients report no risk factors and ALT levels can be normal in up to 20–30% of patients with chronic HCV infection. The aim of this study was to assess the HCV seroprevalence in patients visiting two tertiary care emergency departments in Berlin and Frankfurt, respectively.
Methods: Between May 2008 and March 2010, a total of 28,809 consecutive patients were screened for the presence of anti-HCV antibodies. Anti-HCV positive sera were subsequently tested for HCV-RNA.
Results: The overall HCV seroprevalence was 2.6% (95% CI: 2.4–2.8; 2.4% in Berlin and 3.5% in Frankfurt). HCV-RNA was detectable in 68% of anti-HCV positive cases. Thus, the prevalence of chronic HCV infection in the overall study population was 1.6% (95% CI 1.5–1.8). The most commonly reported risk factor was former/current injection drug use (IDU; 31.2%) and those with IDU as the main risk factor were significantly younger than patients without IDU (p<0.001) and the male-to-female ratio was 72% (121 vs. 46 patients; p<0.001). Finally, 18.8% of contacted HCV-RNA positive patients had not been diagnosed previously.
Conclusions: The HCV seroprevalence was more than four times higher compared to current estimates and almost one fifth of contacted HCV-RNA positive patients had not been diagnosed previously.
Recent evidence has demonstrated additional roles for the neuronal guidance protein receptor UNC5B outside the nervous system. Given the fact that ischemia reperfusion injury (IRI) of the liver is a common source of liver dysfunction and the role of UNC5B during an acute inflammatory response we investigated the role of UNC5B on acute hepatic IRI. We report here that UNC5B+/− mice display reduced hepatic IRI and neutrophil (PMN) infiltration compared to WT controls. This correlated with serum levels of lactate dehydrogenase (LDH), aspartate- (AST) and alanine- (ALT) aminotransferase, the presence of PMN within ischemic hepatic tissue, and serum levels of inflammatory cytokines. Moreover, injection of an anti-UNC5B antibody resulted in a significant reduction of hepatic IR injury. This was associated with reduced parameters of liver injury (LDH, ALT, AST) and accumulation of PMN within the injured hepatic tissue. In conclusion our studies demonstrate a significant role for UNC5B in the development of hepatic IRI and identified UNC5B as a potential drug target to prevent liver dysfunction in the future.
Background: Dopamine plays an important role in orienting and the regulation of selective attention to relevant stimulus characteristics. Thus, we examined the influences of functional variants related to dopamine inactivation in the dopamine transporter (DAT1) and catechol-O-methyltransferase genes (COMT) on the time-course of visual processing in a contingent negative variation (CNV) task.
Methods: 64-channel EEG recordings were obtained from 195 healthy adolescents of a community-based sample during a continuous performance task (A-X version). Early and late CNV as well as preceding visual evoked potential components were assessed.
Results: Significant additive main effects of DAT1 and COMT on the occipito-temporal early CNV were observed. In addition, there was a trend towards an interaction between the two polymorphisms. Source analysis showed early CNV generators in the ventral visual stream and in frontal regions. There was a strong negative correlation between occipito-temporal visual post-processing and the frontal early CNV component. The early CNV time interval 500–1000 ms after the visual cue was specifically affected while the preceding visual perception stages were not influenced.
Conclusions: Late visual potentials allow the genomic imaging of dopamine inactivation effects on visual post-processing. The same specific time-interval has been found to be affected by DAT1 and COMT during motor post-processing but not motor preparation. We propose the hypothesis that similar dopaminergic mechanisms modulate working memory encoding in both the visual and motor and perhaps other systems.
The Arabidopsis arenosa complex is closely related to the model plant Arabidopsis thaliana. Species and subspecies in the complex are mainly biennial, predominantly outcrossing, herbaceous, and with a distribution range covering most parts of latitudes and the eastern reaches of Europe. In this study we present the first comprehensive evolutionary history of the A. arenosa species complex, covering its natural range, by using chromosome counts, nuclear AFLP data, and a maternally inherited marker from the chloroplast genome [trnL intron (trnL) and trnL/F intergenic spacer (trnL/F-IGS) of tRNALeu and tRNAPhe, respectively]. We unravel the broad-scale cytogeographic and phylogeographic patterns of diploids and tetraploids. Diploid cytotypes were exclusively found on the Balkan Peninsula and in the Carpathians while tetraploid cytotypes were found throughout the remaining distribution range of the A. arenosa complex. Three centers of genetic diversity were identified: the Balkan Peninsula, the Carpathians, and the unglaciated Eastern and Southeastern Alps. All three could have served as long-term refugia during Pleistocene climate oscillations. We hypothesize that the Western Carpathians were and still are the cradle of speciation within the A. arenosa complex due to the high species number and genetic diversity and the concurrence of both cytotypes there.
Staurosporine induces necroptotic cell death under caspase-compromised conditions in U937 cells
(2012)
For a long time necrosis was thought to be an uncontrolled process but evidences recently have revealed that necrosis can also occur in a regulated manner. Necroptosis, a type of programmed necrosis is defined as a death receptor-initiated process under caspase-compromised conditions. The process requires the kinase activity of receptor-interacting protein kinase 1 and 3 (RIPK1 and RIPK3) and mixed lineage kinase domain-like protein (MLKL), as a substrate of RIPK3. The further downstream events remain elusive. We applied known inhibitors to characterize the contributing enzymes in necroptosis and their effect on cell viability and different cellular functions were detected mainly by flow cytometry. Here we report that staurosporine, the classical inducer of intrinsic apoptotic pathway can induce necroptosis under caspase-compromised conditions in U937 cell line. This process could be hampered at least partially by the RIPK1 inhibitor necrotstin-1 and by the heat shock protein 90 kDa inhibitor geldanamycin. Moreover both the staurosporine-triggered and the classical death ligand-induced necroptotic pathway can be effectively arrested by a lysosomal enzyme inhibitor CA-074-OMe and the recently discovered MLKL inhibitor necrosulfonamide. We also confirmed that the enzymatic role of poly(ADP-ribose)polymerase (PARP) is dispensable in necroptosis but it contributes to membrane disruption in secondary necrosis. In conclusion, we identified a novel way of necroptosis induction that can facilitate our understanding of the molecular mechanisms of necroptosis. Our results shed light on alternative application of staurosporine, as a possible anticancer therapeutic agent. Furthermore, we showed that the CA-074-OMe has a target in the signaling pathway leading to necroptosis. Finally, we could differentiate necroptotic and secondary necrotic processes based on participation of PARP enzyme.
Atomic-level analyses of non-native protein ensembles constitute an important aspect of protein folding studies to reach a more complete understanding of how proteins attain their native form exhibiting biological activity. Previously, formation of hydrophobic clusters in the 6 M urea-denatured state of an ultrafast folding mini-protein known as TC5b from both photo-CIDNP NOE transfer studies and FCS measurements was observed. Here, we elucidate the structural properties of this mini-protein denatured in 6 M urea performing 15N NMR relaxation studies together with a thorough NOE analysis. Even though our results demonstrate that no elements of secondary structure persist in the denatured state, the heterogeneous distribution of R2 rate constants together with observing pronounced heteronuclear NOEs along the peptide backbone reveals specific regions of urea-denatured TC5b exhibiting a high degree of structural rigidity more frequently observed for native proteins. The data are complemented with studies on two TC5b point mutants to verify the importance of hydrophobic interactions for fast folding. Our results corroborate earlier findings of a hydrophobic cluster present in urea-denatured TC5b comprising both native and non-native contacts underscoring their importance for ultra rapid folding. The data assist in finding ways of interpreting the effects of pre-existing native and/or non-native interactions on the ultrafast folding of proteins; a fact, which might have to be considered when defining the starting conditions for molecular dynamics simulation studies of protein folding.
Sponges play a key role in Antarctic marine benthic community structure and dynamics and are often a dominant component of many Southern Ocean benthic communities. Understanding the drivers of sponge distribution in Antarctica enables us to understand many of general benthic biodiversity patterns in the region. The sponges of the Antarctic and neighbouring oceanographic regions were assessed for species richness and biogeographic patterns using over 8,800 distribution records. Species-rich regions include the Antarctic Peninsula, South Shetland Islands, South Georgia, Eastern Weddell Sea, Kerguelen Plateau, Falkland Islands and north New Zealand. Sampling intensity varied greatly within the study area, with sampling hotspots found at the Antarctic Peninsula, South Georgia, north New Zealand and Tierra del Fuego, with limited sampling in the Bellingshausen and Amundsen seas in the Southern Ocean. In contrast to previous studies we found that eurybathy and circumpolar distributions are important but not dominant characteristics in Antarctic sponges. Overall Antarctic sponge species endemism is ~43%, with a higher level for the class Hexactinellida (68%). Endemism levels are lower than previous estimates, but still indicate the importance of the Polar Front in isolating the Southern Ocean fauna. Nineteen distinct sponge distribution patterns were found, ranging from regional endemics to cosmopolitan species. A single, distinct Antarctic demosponge fauna is found to encompass all areas within the Polar Front, and the sub-Antarctic regions of the Kerguelen Plateau and Macquarie Island. Biogeographical analyses indicate stronger faunal links between Antarctica and South America, with little evidence of links between Antarctica and South Africa, Southern Australia or New Zealand. We conclude that the biogeographic and species distribution patterns observed are largely driven by the Antarctic Circumpolar Current and the timing of past continent connectivity.
Background: Dabigatran etexilate (DE) is a new oral direct thrombin inhibitor. Clinical trials point towards a favourable risk-to-benefit profile of DE compared to warfarin. In this study, we evaluated whether hemorrhagic transformation (HT) occurs after experimental stroke under DE treatment as we have shown for warfarin.
Methods: 44 male C57BL/6 mice were pretreated orally with 37.5 mg/kg DE, 75 mg/kg DE or saline and diluted thrombin time (dTT) and DE plasma concentrations were monitored. Ischemic stroke was induced by transient middle cerebral artery occlusion (tMCAO) for 1 h or 3 h. We assessed functional outcome and HT blood volume 24 h and 72 h after tMCAO.
Results: After 1 h tMCAO, HT blood volume did not differ significantly between mice pretreated with DE 37.5 mg/kg and controls (1.5±0.5 µl vs. 1.8±0.5 µl, p>0.05). After 3 h tMCAO, DE-anticoagulated mice did also not show an increase in HT, neither at the dose of 37.5 mg/kg equivalent to anticoagulant treatment in the therapeutic range (1.3±0.9 µl vs. control 2.3±0.5 µl, p>0.05) nor at 75 mg/kg, clearly representing supratherapeutic anticoagulation (1.8±0.8 µl, p>0.05). Furthermore, no significant increase in HT under continued anticoagulation with DE 75 mg/kg could be found at 72 h after tMCAO for 1 h (1.7±0.9 µl vs. control 1.6±0.4 µl, p>0.05).
Conclusion: Our experimental data suggest that DE does not significantly increase hemorrhagic transformation after transient focal cerebral ischemia in mice. From a translational viewpoint, this indicates that a continuation of DE anticoagulation in case of an ischemic stroke might be safe, but clearly, clinical data on this question are warranted.
Temporal variation in the detectability of a species can bias estimates of relative abundance if not handled correctly. For example, when effort varies in space and/or time it becomes necessary to take variation in detectability into account when data are analyzed. We demonstrate the importance of incorporating seasonality into the analysis of data with unequal sample sizes due to lost traps at a particular density of a species. A case study of count data was simulated using a spring-active carabid beetle. Traps were ‘lost’ randomly during high beetle activity in high abundance sites and during low beetle activity in low abundance sites. Five different models were fitted to datasets with different levels of loss. If sample sizes were unequal and a seasonality variable was not included in models that assumed the number of individuals was log-normally distributed, the models severely under- or overestimated the true effect size. Results did not improve when seasonality and number of trapping days were included in these models as offset terms, but only performed well when the response variable was specified as following a negative binomial distribution. Finally, if seasonal variation of a species is unknown, which is often the case, seasonality can be added as a free factor, resulting in well-performing negative binomial models. Based on these results we recommend (a) add sampling effort (number of trapping days in our example) to the models as an offset term, (b) if precise information is available on seasonal variation in detectability of a study object, add seasonality to the models as an offset term; (c) if information on seasonal variation in detectability is inadequate, add seasonality as a free factor; and (d) specify the response variable of count data as following a negative binomial or over-dispersed Poisson distribution.
Although their applications have not yet extended widely due to their incipient state, nano-technologies and nano-medicines may be presumed to be at the origin of the next great technological revolution, foreseeably contributing to a new stage with respect to evolutions in mankind’s progress. Their possibilities are truly immense in enormously varied spheres, but the risks and uncertainties they engender are enormous too. Because access and use of the unceasingly increasing mega-quantity of information they generate will place further strain on the protection of personal life, privacy, the exercise of freedom, as well as the safeguarding of other fundamental principles and rights.
Background: Adaptation to low oxygen by changing gene expression is vitally important for cell survival and tissue development. The sprouting of new blood vessels, initiated from endothelial cells, restores the oxygen supply of ischemic tissues. In contrast to the transcriptional response induced by hypoxia, which is mainly mediated by members of the HIF family, there are only few studies investigating alternative splicing events. Therefore, we performed an exon array for the genome-wide analysis of hypoxia-related changes of alternative splicing in endothelial cells.
Methodology/Principal findings: Human umbilical vein endothelial cells (HUVECs) were incubated under hypoxic conditions (1% O(2)) for 48 h. Genome-wide transcript and exon expression levels were assessed using the Affymetrix GeneChip Human Exon 1.0 ST Array. We found altered expression of 294 genes after hypoxia treatment. Upregulated genes are highly enriched in glucose metabolism and angiogenesis related processes, whereas downregulated genes are mainly connected to cell cycle and DNA repair. Thus, gene expression patterns recapitulate known adaptations to low oxygen supply. Alternative splicing events, until now not related to hypoxia, are shown for nine genes: six which are implicated in angiogenesis-mediated cytoskeleton remodeling (cask, itsn1, larp6, sptan1, tpm1 and robo1); one, which is involved in the synthesis of membrane-anchors (pign) and two universal regulators of gene expression (cugbp1 and max).
Conclusions/Significance: For the first time, this study investigates changes in splicing in the physiological response to hypoxia on a genome-wide scale. Nine alternative splicing events, until now not related to hypoxia, are reported, considerably expanding the information on splicing changes due to low oxygen supply. Therefore, this study provides further knowledge on hypoxia induced gene expression changes and presents new starting points to study the hypoxia adaptation of endothelial cells.