Crop wild relative populations of Beta vulgaris allow direct mapping of agronomically important genes

Rapid identification of agronomically important genes is of pivotal interest for crop breeding. One source of such genes are crop wild relative (CWR) populations. Here we used a CWR population of <200 wild beets (B. vulgaris ssp. maritima), sampled in their natural habitat, to identify the sugar beet (Beta vulgaris ssp. vulgaris) resistance gene Rz2 with a modified version of mapping-by-sequencing (MBS). For that, we generated a draft genome sequence of the wild beet. Our results show the importance of preserving CWR in situ and demonstrate the great potential of CWR for rapid discovery of causal genes relevant for crop improvement. The candidate gene for Rz2 was identified by MBS and subsequently corroborated via RNA interference (RNAi). Rz2 encodes a CC-NB-LRR protein. Access to the DNA sequence of Rz2 opens the path to improvement of resistance towards rhizomania not only by marker-assisted breeding but also by genome editing.

Variation among wild relatives of crop plants can be used to identify genes underlying traits of agronomic importance. Here, the authors show that a modified mapping-by-sequencing approach can rapidly identify the genetic basis for viral resistance in sugar beet using wild beet populations in their natural habitat.

Cognitive interventions in mild Alzheimer's disease: a therapy-evaluation study on the interaction of medication and cognitive treatment

Background/Aims

Many studies have shown that not only pharmacological treatment but also cognitive stimulation in the early stages of Alzheimer's disease (AD) improves language processing and (other) cognitive functions, stabilizes Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL) functions and increases the subjective quality of life (wherein a combination of pharmacological intervention and cognitive stimulation could provide greater relief of clinical symptoms than either intervention given alone). Today, it is no longer the question of whether cognitive stimulation helps but rather what kind of stimulation helps more than others.

Methods

A sample of 42 subjects with mild AD (all medicated with an acetylcholinesterase inhibitor and well adjusted) underwent clinical and cognitive evaluation and participated in a 6-month study with 2 experimental groups (i.e. ‘client-centered’ global stimulation vs. cognitive training) and a control group. Since the test performance also depends on the individual test, we used a wide variety of tests; we z-transformed the results and then calculated the mean value for the global cognitive status (using the Mini-Mental State Examination) as well as for the single functional areas.

Results

Between-group differences were found, they were overall in favor of the experimental groups. Different functional areas led to different treatment and test patterns. Client-centered, global, cognitive therapy stimulated many cognitive functions and thus led to a better performance in language processing and ADL/IADL. The subjective quality of life increased as well. The cognitive training (of working memory) improved only the ADL/IADL performance (more, however, than client-centered, global, cognitive stimulation) and stabilized the level of performance in the other three functional areas.

© 2013 S. Karger AG, Basel

Risk and monitoring based indicators of receiving water status: alternative or complementary elements in IWRM?

The European Water Framework Directive (WFD) was enacted in the year 2000 with a stepwise approach. After legal implementation in the various member states large efforts were undertaken for the initial characterization of water bodies, risk assessment, to implement extensive monitoring schemes and to develop management plans at different aggregation levels by the year 2010. The initial characterization process and risk assessment had to be finalized by 2004 and delineated water bodies including a typological classification and identified the significant pressures and impacts in a screening procedure. In parallel, monitoring programmes and new biological indicator systems were developed in order to proof and refine the results of the risk assessment with an ecological indicator based assessment in a subsequent step which was finalized in 2009. Although the risk assessment for Germany was based on existing data that were originally collected for other purposes and came from a large variety of environmental or economical sectors, the results differ only slightly from the monitoring and indicator based information with respect to classifications of the 'ecological status' and 'chemical status'. From this result we conclude that a risk assessment based on a careful application and intelligent combination of existing data sources with proven quality allows the recognition of trends and the identification of priorities for action of measures already at an early stage of a management process. However, monitoring schemes and advanced sets of ecological indicators are essential in later management steps both for narrowing uncertainties remaining from the risk assessment and to allow for effect controls of implemented measures. Moreover, these monitoring indicators should differentiate the effects of multiple stressors more factor specific and with respect to ecosystem states and functions. In conclusion, we see risk and indicator based assessments as complementary elements in Integrated Water Resources Management (IWRM), which have to be linked in systematic and phased procedures.

Element patterns for particulate matter in stormwater effluent

Particulate matter in stormwater deteriorates the quality of receiving water and sediment. Characterization of stormwater particulate matter by means of its particle-associated element pattern provides an aid to determining its impact on receiving surface waters. During a 6 month measurement campaign, we determined particle-associated concentrations of major pollutants and rare earths for three combined water/stormwater outlets in the town of Stassfurt. We differentiated the particle-associated constituents on the basis of a hierarchical cluster analysis. Repeating the cluster analysis on random subsets, we gained information about the variability of the element patterns between and within the sites. In general, constituents associated with sewage and sewer sediment behave differently compared with constituents associated with runoff. The degree to which associations can be established for element patterns from site to site is limited by the variability encountered within sample sets taken from individual sites. The latter variability depends on the complexity of the catchment.

Identification of significant pressures and impacts upon receiving waters

This study gives a review on the process of identification of significant pressures and impacts, which is an important part of river basin planning and in particular for implementing the EU Water Framework Directive (WFD) (2000/60/EC). The questions: what is a "significant pressure" in terms of the WFD? which sources and driving forces have to be regarded? which data can be used? which pressure on a water body is significant? and which implications and requirements result from the identification process?--should be considered. The European Commission requires reporting from all Member States about the status of the water bodies within a river basin district and about the risk of failing the environmental objectives by the end of 2004. Therefore, a number of prevailing projects across Europe aim to develop a guideline on a common understanding of the most effective approach towards the identification of significant anthropogenic pressures, and the analysis of potential impacts including the identification of appropriate tools and models. In such a guideline suitable and intelligent criteria have to be developed in order to enable a uniform assessment of the anthropogenic pressures within a river basin district.

River Water Quality Model no. 1 (RWQM1): I. Modelling approach

Successful river water quality modelling requires the specification of an appropriate model structure and process formulation. Both must be related to the compartment structure of running water ecosystems including their longitudinal, vertical, and lateral zonation patterns. Furthermore, the temporal variability of abiotic boundary conditions may be important and must be incorporated by an appropriate choice of model parameters. A six-step decision procedure is proposed to achieve these objectives. The steps address the determination of the following model features: (1) temporal representation (dynamic or steady-state); (2) model dimensionality; (3) mixing; (4) advection; (5) reaction terms; and (6) boundary conditions. Numerical criteria based on process time constants and length scales provide a basis for these decisions.

River Water Quality Model no. 1 (RWQM1): II. Biochemical process equations

In this paper, biochemical process equations are presented as a basis for water quality modelling in rivers under aerobic and anoxic conditions. These equations are not new, but they summarise parts of the development over the past 75 years. The primary goals of the presentation are to stimulate communication among modellers and field-oriented researchers of river water quality and of wastewater treatment, to facilitate practical application of river water quality modelling, and to encourage the use of elemental mass balances for the derivation of stoichiometric coefficients of biochemical transformation processes. This paper is part of a series of three papers. In the first paper, the general modelling approach is described; in the present paper, the biochemical process equations of a complex model are presented; and in the third paper, recommendations are given for the selection of a reasonable submodel for a specific application.

River Water Quality Model no. 1 (RWQM1): case study. I. Compartmentalisation approach applied to oxygen balances in the River Lahn (Germany)

A case study on the application of the River Water Quality Model No. 1 (RWQM1) is presented in order to illustrate the importance of modelling a sediment compartment for an ecologically meaningful assessment of the impact of wastewater effluents and combined sewer overflows. The focus of this case study is on the compartmentalisation approach of the RWQM1 that makes such a description possible. In contrast to this, a strongly simplified biochemical submodel is used that considers only oxygen and dissolved substrate. The object of the case study is the River Lahn, a moderately polluted 5th order stream in Germany, for which the connectivity of surface/subsurface flows and mass fluxes within river sediments have been intensively investigated. The hyporheic flow between a downwelling and upwelling zone of a riffle-pool sequence has been studied with the aid of tracer experiments and continuous records of water constituents. High diurnal fluctuations of oxygen travelled to considerable depth of the sediment and oxygen in the interstitial water decreased considerably while travelling through the riffle. Starting with the implementation of a strongly simplified version of the biochemical part of the RWQM1, but with the consideration of a sediment pore water compartment in addition to the water column compartment, a calibration procedure is performed using tracer data from the water column and the sediment. The calibrated model is then used to study the system response to wastewater treatment plant effluent and combined sewer overflow emissions. The modelling approach makes it possible to quantify the sediment oxygen demand and the spatial and temporal extent of sediment zones with oxygen depletion. However, the spatially averaged approach does not account for inhomogeneities in the sediment. It is shown that for this river with its alluvial coarse sediments even moderate emissions from sewerage systems may be high enough to drop sediment oxygen concentrations to low levels while those in the surface flow remain close to saturation. Similarly, it is demonstrated that combined sewer overflows may cause anoxic sediment oxygen conditions for extended time periods. The implications for ecologically sound river water quality modelling and for specific quality objectives are discussed.

River Water Quality Model no. 1 (RWQM1): III. Biochemical submodel selection

The new River Water Quality Model no. 1 introduced in the two accompanying papers by Shanahan et al. and Reichert et al. is comprehensive. Shanahan et al. introduced a six-step decision procedure to select the necessary model features for a certain application. This paper specifically addresses one of these steps, i.e. the selection of submodels of the comprehensive biochemical conversion model introduced in Reichert et al. Specific conditions for inclusion of one or the other conversion process or model component are introduced, as are some general rules that can support the selection. Examples of simplified models are presented.

Endogenous natriuretic factors 6: the stereochemistry of a natriuretic gamma-tocopherol metabolite LLU-alpha

2,7,8-Trimethyl-(S)-2-(beta-carboxyethyl)-6-hydroxy chroman (S-LLU-alpha) isolated from human uremic urine is apparently an oxidative side-chain degradation product of gamma-tocopherol. This compound exhibits natriuretic activity in vivo and it appears to mediate the inhibition of the 70 pS K+ channel in the apical membrane of the thick ascending limb of the nephron. The stereochemistry at the C-2 of LLU-alpha has been unequivocally established to be S(+) by X-ray crystallographic analysis of a diastereomeric amide derivative. It was also established that the chroman ring oxidation of S-LLU-alpha proceeded without racemization at C-2. This finding can be extended to nonepimerization at C-2 of alpha-delta tocopherols (Vitamin E) during side-chain oxidation and stereospecificity (retention or inversion) of oxidative opening of the chroman ring. The resolution of the enantiomers of the parent compound and derivatives was accomplished by chiral high-performance liquid chromatography. The stereospecific enzymatic hydrolysis by an array of commercially available enzymes of the racemic methyl ester of LLU-alpha was investigated. The lipase from Humicola languinosa appears to be the best enzyme for resolution by selective hydrolysis of the racemic methyl ester.

Spectroscopic evidence for preexisting T- and R-state insulin hexamer conformations

The insulin hexamer is an allosteric protein exhibiting both positive and negative cooperative homotropic interactions and positive cooperative heterotropic interactions (C. R. Bloom et al., J. Mol. Biol. 245, 324-330, 1995). In this study, detailed spectroscopic analyses of the UV/Vis absorbance spectra of the Co(II)-substituted human insulin hexamer and the 1H NMR spectra of the Zn(II)-substituted hexamer have been carried out under a variety of ligation conditions to test the applicability of the sequential (KNF) and the half-site reactivity (SMB) models for allostery. Through spectral decomposition of the characteristic d-->d transitions of the octahedral Co(II)-T-state and tetrahedral Co(II)-R-state species, and analysis of the 1H NMR spectra of T- and R-state species, these studies establish the presence of preexisting T- and R-state protein conformations in the absence of ligands for the phenolic pockets. The demonstration of preexisting R-state species with unoccupied sites is incompatible with the principles upon which the KNF model is based. However, the SMB model requires preexisting T- and R-states. This feature, and the symmetry constraints of the SMB model make it appropriate for describing the allosteric properties of the insulin hexamer.

[Radiation protection through cytokine release by N-acetylcysteine]

BACKGROUND

Interleukin-1, tumornecrosisfactor-alpha and interferon-gamma endogenously provide protection of the hematopoietic system against radiation. Thiols have already been used successfully as radioprotective agents. In this study the effect von N-acetylcysteine (NAC) on the release of interleukin-1 alpha and beta (IL-1), interleukin-2 (IL-2), interferon-gamma (IFN-gamma) and tumornecrosisfactor-alpha (TNF-alpha) was assessed in an in vitro assay.

PATIENTS AND METHODS

Whole blood samples from 8 healthy volunteers were stimulated with 7.5 micrograms/ml PHA. NAC was added at concentrations of 0.6, 6, 12 and 24 mmol/l. Subsequently the samples were irradiated with a dose of 18 Gy according to preceding validation experiments.

RESULTS

IL-1 alpha, IL-1 beta b and IL-2: In comparison to stimulation and radiation alone the addition of 0.6 and 6 mmol/l, with IL-2 also 12 mmol/l, NAC resulted in a significant increase of the cytokine-concentrations. The highest concentration of 24 mmol/l NAC, however, resulted in a decrease beyond control levels. IFN-gamma and TNF-alpha: Until 12 mmol/l NAC no changes were observed. 24 mmol/l NAC resulted in a significant decrease, too.

CONCLUSION

N-acetylcysteine is capable to co-stimulate radioprotective cytokines like IL-1 alpha and IL-1 beta and to enhance IL-2 in vitro, whereas higher doses result in a suppression.

Structural asymmetry and half-site reactivity in the T to R allosteric transition of the insulin hexamer

The zinc-insulin hexamer, the storage form of insulin in the pancreas, is an allosteric protein capable of undergoing transitions between three distinct conformational states, designated T6, T3R3, and R6, on the basis of their ligand binding properties, allosteric behavior, and pseudo point symmetries [Kaarsholm, N. C., Ko, H.-C., & Dunn, M. F. (1989) Biochemistry 28, 4427-4435]. The transition from the T-state to the R-state involves a coil-to-helix transition in residues 1-8 of the B-chain wherein the ring of PheB1 is displaced by approximately 30 A. This motion also is accompanied by small changes in the positions of A-chain residues and other B-chain residues. In this paper, one- and two-dimensional (COSY and NOESY) 1H NMR are used to characterize the ligand-induced T to R transitions of wild-type and EB13Q mutant human zinc-insulin hexamers and to make sequence-specific assignments of all resonances in the aromatic region of the R6 complex with resorcinol. The changes in the 1H NMR spectrum (at 500 and 600 MHz) that occur during the T to R transition provide specific signatures of the conformation change. Analysis of the dependence of these spectral changes for the phenol-induced transition as a function of the concentration of phenol establish (1) that the interconversion of T6 and R6 occurs via a third species assigned as T3R3 and (2) that the system shows both negative and positive cooperative allosteric behavior. One- and two-dimensional COSY and NOESY studies show that, in the absence of phenolic compounds, anions act as heterotropic effectors that shift the distribution of hexamer conformations in favor of the R-state with the order of effectiveness, SCN- > N3- >> I- >> Cl-. Analysis of one- and two-dimensional spectra indicate that with wild-type insulin, SCN- and N3- give T3R3 species, whereas the EB13Q mutant gives an R6 species. An allosteric model for the insulin T to R transition based on the structural asymmetry model [Seydoux, F., Malhotra, O. P., & Bernhard, S. A. (1974) CRC Crit. Rev. Biochem. 2, 227-257] is proposed that explains the negative and positive allosteric properties of the system, including the role of T3R3 and the action of homotropic and heterotropic effectors.

[Significance of historical and current hallucinogenic research in psychiatry]

Research in experimental psychosis has a long tradition extending through several stages. With the world wide abuse of psychoactive substances it came to an abrupt end. Systematic questions within this framework of research are still unresolved, and research on newly developed compounds is almost completely lacking. A review of the pharmacological and psychological effects of various psychoactive agents is provided, and results of recent experimental studies on arylalkylamines are discussed. It is argued that from a systematic as well as from a methodological viewpoint the traditional approach of experimental psychosis represents a valuable tool in psychiatric research.

Psychological effects of MDE in normal subjects. Are entactogens a new class of psychoactive agents?

The so-called entactogens 3,4-methylenedioxymethamphetamine ([MDMA] also known as "Ecstasy," or "Adam") and its analog 3,4-methylenedioxyethamphetamine ([MDE] also known as "Eve") exert similar psychotropic effects in humans. Two double-blind placebo-controlled psychometric studies with normal control subjects were conducted. Placebo or MDE (140 mg) was administered orally to eight male volunteers at 1:30 P.M. and to six subjects (3 male, 3 female) at 11 P.M. Psychologic tests and clinical ratings were performed 1 hour before the administration of the drugs, as well as 2, 5, and 24 hours after drug intake and 7 days thereafter in the first study. In the second study, measures were taken at times -1, +8.5, +24 hours, and +7 days. The majority of the psychotropic effects resembled those that have already been described in anecdotal reports. The substance produced a partially controllable state of enhanced insight, empathy, and peaceful feelings. All subjects displayed a general stimulation with increased psychomotor drive, logorrhea, and facilitation of communication. One of the fourteen volunteers developed a toxic psychosis. One volunteer displayed a dysphoric reaction, one suffered from episodes of anxiety for some days after the experiment. The findings support the hypothesis that MDMA and MDE represent a novel pharmacologic class.

Mescaline-induced psychopathological, neuropsychological, and neurometabolic effects in normal subjects: experimental psychosis as a tool for psychiatric research

The psychological, neuropsychological, and neurometabolic effects of the hallucinogenic agent mescaline were investigated in 12 normal men who were volunteers. Mescaline produced an acute psychotic state 3 1/2-4 hr after drug intake, as measured by the Brief Psychiatric Rating Scale (BPRS) and Paranoid Depression Scale (PDS). The Assessment of Altered States of Consciousness (APZ) questionnaire revealed specific effects of mescaline in the visual system. Neuropsychological effects were studied with a face/nonface decision task with known right-hemisphere advantage, in which mescaline induced a decrease of functioning of the right hemisphere. In functional brain imaging using single photon emission computed tomography (SPECT), mescaline produced a "hyperfrontal" pattern with an emphasis on the right hemisphere, which was correlated with mescaline-induced psychotic psychopathology. Our findings question the validity of the concept of hypofrontality as an explanation for schizophrenic symptomatology. The study of psychoactive substances under controlled laboratory conditions has the methodological advantage of intraindividual control, and hence, minimal variability of data.

[Relations of model and drug-induced psychoses to schizophrenic diseases]

From the clinical point of view, substance-induced psychosis can be rather similar to schizophrenia. However, the question whether phenomenological resemblances represent similar underlying causal mechanisms is unsolved. Whereas the interest in experimentally induced psychosis was purely academic until the mid-1960s, the widespread use of "recreational" drugs provided this research with an important practical impact. With respect to a given case the differential diagnosis between schizophrenia and drug-induced psychosis it is often problematic. The differences in psychopathology refer to the disturbances of experience in general (Ichstörungen), the character of the hallucinations and the quality and quantity of the alterations of consciousness. Contrary to the sharp distinctions which used to be drawn between schizophrenia and drug-induced psychotic states, we hold that these states are rather similar, and may even represent a common underlying pathology. Hence, the renewed interest in the study on experimentally induced psychotic states using advanced methodology seems justified.

The T to R transition in the copper(II)-substituted insulin hexamer. Anion complexes of the R-state species exhibiting type 1 and type 2 spectral characteristics

The R-state conformation of the Cu(II)-substituted insulin hexamer has been identified, and a number of its derivatives have been studied via 1H NMR, ESR, and UV-visible spectroscopy. This work establishes that the Cu(II)-substituted insulin hexamer undergoes an analogous T to R conformational transition in solution that has been identified previously for Zn(II)- and Co(II)-insulin hexamers [Roy, M., Brader, M.L., Lee, R. W.-K., Kaarsholm, N.C., Hansen, J., & Dunn, M.F. (1989) J. Biol. Chem. 264, 19081-19085]. The data indicate that each Cu(II) center of the R-state Cu(II)-insulin hexamer possesses a coordination site that is accessible to anions from solution. Both phenol and anionic ligands that coordinate to the Cu(II) ions are required to generate the necessary heterotropic interactions that stabilize the R-state structure. With phenylmethylthiolate (PMT), a Cu(II)-R6 adduct that displays the spectral features of blue (type 1) copper proteins is obtained. This complex is proposed to embody a pseudotetrahedral CuIIN3S(PMT) chromophore, in which N is HisB10 (imidazolyl). The remaining ligands examined gave rise to Cu(II)-R6 adducts that possessed the spectral characteristics of normal (type 2) Cu(II) proteins. Under reducing conditions, Cu(I)-T6 and Cu(I)-R6 hexamers have been identified.

[Cytotoxicity of lipid ether ilmofosine in combination with radiotherapy in vitro]

Alkyllysophospholipids (ALP) represent a new class of cytotoxic agents. The cytotoxic potential was demonstrated by in vivo and in vitro models. In this study the interaction of the ALP Ilmofosine in combination with radiotherapy was tested in vitro using the colony forming assay. The cell lines B-16, K-562 and Meth-A were used as targets. The cell lines showed similar sensitivity to radiation therapy. The B-16 cell line proved to be resistant to Ilmofosine; the K-562 cell line showed little sensitivity whereas the Meth-A cell line was very sensitive to Ilmofosine. In the K-562 and Meth-A cell lines that were sensitive to both agents a clear addition of both effects was observed. In the case of the B-16 cell line in combination no effect was seen exceeding the pure radiation effect. No synergistic and no antagonistic effect was observed.

[Dose distribution of electrons obtained from linear accelerators equipped with a beam scanning system]

Homogeneous distribution of electrons used for therapeutic purposes and obtained from accelerators, is achieved by means of Potter-Bucky diaphragms or by repeated, staggered, sawtooth-shaped sweeping movements of the electron beam (scanning) over the radiation field. The repetition of the scanning process (number of scans) can result in long measurement times for achieving a sufficiently homogeneous, dosimetrically adequate distribution of the electrons. This "time problem" makes it imperative to achieve good homogeneity while keeping the number of scans as low as possible. To solve the problem, the scanning movement of the electron beam is simulated by a computer programme and the interdependence of the homogeneity of the irradiation field and number of scans is investigated. Since changing the ratio of the two deflection rates exercises a significant influence, it is mandatory in dosimetry to pay close attention to a strict observance of the deflection rates.