Emotional experience in patients with clinically isolated syndrome and early multiple sclerosis.

BACKGROUND AND PURPOSE: Evidence suggests that there are changes in the processing of emotional information (EP) in people with multiple sclerosis (MS). It is unclear which functional domains of EP are affected, whether these changes are secondary to other MS-related neuropsychological or psychiatric symptoms and if EP changes are present in early MS. The aim of the study was to investigate EP in patients with early MS (clinically isolated syndrome and early relapsing/remitting MS) and healthy controls (HCs). METHODS: A total of 29 patients without neuropsychological or psychiatric deficits and 29 matched HCs were presented with pictures from the International Affective Picture System with negative, positive or neutral content. Participants rated the induced emotion regarding valence and arousal using nine-level Likert scales. A speeded recognition test assessed memory for the emotional stimuli and for the emotional modulation of response time. A subgroup of participants was tested during a magnetic resonance imaging (MRI) session. RESULTS: Patients in the MRI subgroup rated the experience induced by pictures with positive or negative emotional content significantly more weakly than HCs. Further, these patients were significantly less aroused when watching the pictures from the International Affective Picture System. There were no effects in the non-MRI subgroup or effects on emotional memory or response times. CONCLUSIONS: Emotional processing changes may be present in early MS in the form of flattened emotional experience on both the valence and arousal dimensions. These changes do not appear to be secondary to neuropsychological or psychiatric deficits. The fact that emotional flattening was only found in the MRI setting suggests that EP changes may be unmasked within stressful environments and points to the potential yet underestimated impact of the MRI setting on behavioral outcomes.

Termite soldiers contribute to social immunity by synthesizing potent oral secretions.

The importance of soldiers to termite society defence has long been recognized, but the contribution of soldiers to other societal functions, such as colony immunity, is less well understood. We explore this issue by examining the role of soldiers in protecting nestmates against pathogen infection. Even though they are unable to engage in grooming behaviour, we find that the presence of soldiers of the Darwin termite, Mastotermes darwiniensis, significantly improves the survival of nestmates following entomopathogenic infection. We also show that the copious exocrine oral secretions produced by Darwin termite soldiers contain a high concentration of proteins involved in digestion, chemical biosynthesis, and immunity. The oral secretions produced by soldiers are sufficient to protect nestmates against infection, and they have potent inhibitory activity against a broad spectrum of microbes. Our findings support the view that soldiers may play an important role in colony immunity, and broaden our understanding of the possible function of soldiers during the origin of soldier-first societies.

Ectoine protects DNA from damage by ionizing radiation.

Ectoine plays an important role in protecting biomolecules and entire cells against environmental stressors such as salinity, freezing, drying and high temperatures. Recent studies revealed that ectoine also provides effective protection for human skin cells from damage caused by UV-A radiation. These protective properties make ectoine a valuable compound and it is applied as an active ingredient in numerous pharmaceutical devices and cosmetics. Interestingly, the underlying mechanism resulting in protecting cells from radiation is not yet fully understood. Here we present a study on ectoine and its protective influence on DNA during electron irradiation. Applying gel electrophoresis and atomic force microscopy, we demonstrate for the first time that ectoine prevents DNA strand breaks caused by ionizing electron radiation. The results presented here point to future applications of ectoine for instance in cancer radiation therapy.

Ectoine can enhance structural changes in DNA in vitro.

Strand breaks and conformational changes of DNA have consequences for the physiological role of DNA. The natural protecting molecule ectoine is beneficial to entire bacterial cells and biomolecules such as proteins by mitigating detrimental effects of environmental stresses. It was postulated that ectoine-like molecules bind to negatively charged spheres that mimic DNA surfaces. We investigated the effect of ectoine on DNA and whether ectoine is able to protect DNA from damages caused by ultraviolet radiation (UV-A). In order to determine different isoforms of DNA, agarose gel electrophoresis and atomic force microscopy experiments were carried out with plasmid pUC19 DNA. Our quantitative results revealed that a prolonged incubation of DNA with ectoine leads to an increase in transitions from supercoiled (undamaged) to open circular (single-strand break) conformation at pH 6.6. The effect is pH dependent and no significant changes were observed at physiological pH of 7.5. After UV-A irradiation in ectoine solution, changes in DNA conformation were even more pronounced and this effect was pH dependent. We hypothesize that ectoine is attracted to the negatively charge surface of DNA at lower pH and therefore fails to act as a stabilizing agent for DNA in our in vitro experiments.

Volumetric assessment of optic nerve sheath and hypophysis in idiopathic intracranial hypertension.

BACKGROUND AND PURPOSE: Idiopathic intracranial hypertension is a headache syndrome characterized by increased CSF pressure. Compression of the hypophysis and distension of the optic nerve sheath are reliable imaging signs. The purpose of the study was to validate, in patients with idiopathic intracranial hypertension, MR imaging-based volumetric measurements of the optic nerve sheath and hypophysis as an objective observation method for more accurate diagnosis and posttreatment follow-up. MATERIALS AND METHODS: Twenty-three patients with idiopathic intracranial hypertension as well as age-, sex-, and body mass index-matched controls underwent volumetric measurements of the optic nerve, optic nerve sheath, and hypophysis on high-resolution T2-weighted MR images by using a 7-cm surface coil, followed by correlation with CSF opening pressures and clinical symptom scores of visual disturbances and headache. RESULTS: Mean values of optic nerve sheath (341.86 ± 163.69 mm(3) versus 127.56 ± 53.17 mm(3), P < .001) and hypophysis volumes (554.59 ± 142.82 mm(3) versus 686.60 ± 137.84 mm(3), P < .05) differed significantly between healthy and diseased subjects. No significant differences between mean optic nerve volumes were observed. Receiver operating characteristic analysis showed optic nerve sheath volumes of >201.30 mm(3) (sensitivity, 86.96%; specificity, 91.30%) and hypophysis volumes of <611.21 mm(3) (sensitivity, 78.26%; specificity, 69.57%) to be indicative of idiopathic intracranial hypertension diagnosis. In patients with idiopathic intracranial hypertension, no correlations were found between optic nerve sheath and hypophysis volumes and CSF opening pressures or clinical scores of visual disturbances and headache. CONCLUSIONS: Semiautomated volumetric measurement of optic nerve sheath and hypophysis has the potential to more accurately diagnose and follow patients with idiopathic intracranial hypertension.

[Statins and their influence on inflammatory processes in internal carotid artery stenosis]. / Statine und ihr Einfluss auf entzündliche Prozesse in arteriosklerotischen Plaques bei Patienten mit Stenose der Arteria carotis interna.

Arterio-arterial emboli originating from a high-grade stenosis of the internal carotid artery are a common cause for cerebral ischemias. Inflammatory processes are not only pivotal in the development of atherosclerotic vessel wall changes, but also for their clinical destabilization. Inflammatory cells, like macrophages, can turn a chronic high-grade carotid stenosis into a high-risk area for the development of arterial thromboses by way of a complex pathogenesis involving the elevation of proinflammatory factors, biosynthesis of collagen-degrading matrix metalloproteinases and expression of prothrombotic tissue factor. This process could affect the occurrence of perioperative complications during carotid endarterectomies. Statins are potent cholesterol-lowering agents. Among other lipid-independent effects, statins appear to play a significant role in preventing cardiovascular events. A number of studies have shown that statins possess plaque-stabilizing effects and that they improve cerebral autoregulation. A growing evidence supports the preoperative administration of statins in patients with high-grade stenoses of the internal carotid artery.

The ion coupling and organic substrate specificities of osmoregulatory transporter ProP in Escherichia coli.

Transporter ProP of Escherichia coli, a member of the major facilitator superfamily, mediates osmoprotective proline or glycine betaine accumulation by bacteria exposed to high osmolality environments. Morpholinopropane sulfonic acid, a common constituent of microbiological media, accumulates in osmoadapting E. coli cells but it is not osmoprotective and it did not influence proP transcription or ProP activity. The apparent K(m) for proline uptake via ProP increased with decreasing pH in the range 7.5-4. ProP-dependent proline uptake by de-energized bacteria was associated with alkalinization of the external medium. Thus ProP mediates cotransport of H(+) and zwitterionic proline and a transporter functional group with a pK(a) of 5-6 is implicated in catalysis. Exogenous proline or glycine betaine elicits K(+) release from osmoadapting E. coli cells and ProP activity is stimulated by exogenous K(+). However, uptake of proline or glycine betaine stimulated K(+) efflux from K(+)-loaded bacteria which expressed either ProP or alternative, osmoregulatory transporter ProU. This indicated that ProP was unlikely to mediate K(+) efflux. Zwitterions ectoine, pipecolate, proline betaine, N,N-dimethylglycine, carnitine and 1-carboxymethylpyridinium were identified as alternative ProP substrates. Choline, a cation and a structural analogue of glycine betaine, was a low affinity inhibitor but not a substrate of ProP.

Protein ProQ influences osmotic activation of compatible solute transporter ProP in Escherichia coli K-12.

ProP is an osmoregulatory compatible solute transporter in Escherichia coli K-12. Mutation proQ220::Tn5 decreased the rate constant for and the extent of ProP activation by an osmotic upshift but did not alter proP transcription or the ProP protein level. Allele proQ220::Tn5 was isolated, and the proQ sequence was determined. Locus proQ is upstream from prc (tsp) at 41.2 centisomes on the genetic map. The proQ220::Tn5 and prc phenotypes were different, however. Gene proQ is predicted to encode a 232-amino-acid, basic, hydrophilic protein (molecular mass, 25,876 Da; calculated isoelectric point, 9.66; 32% D, E, R, or K; 54.5% polar amino acids). The insertion of PCR-amplified proQ into vector pBAD24 produced a plasmid containing the wild-type proQ open reading frame, the expression of which yielded a soluble protein with an apparent molecular mass of 30 kDa. Antibodies raised against the overexpressed ProQ protein detected cross-reactive material in proQ+ bacteria but not in proQ220::Tn5 bacteria. ProQ may be a structural element that influences the osmotic activation of ProP at a posttranslational level.

Influence of salt concentration on the susceptibility of moderately halophilic bacteria to antimicrobials and its potential use for genetic transfer studies.

The influence of salinity on the susceptibility of 13 moderately halophilic collection strains belonging to the genera Chromohalobacter, Deleya, Halomonas, Vibrio, and Volcaniella to 10 common antimicrobials has been studied. Three different patterns of tolerance were found when salinity was varied from 10 to 1% (wt/vol) total salts in the testing media. The first one included the responses to ampicillin and rifampicin, where only minimal effects on the susceptibility were found. All moderate halophiles showed a high sensitivity to rifampicin regardless of the salt concentration. In the second group, including the responses to the aminoglycosides gentamycin, kanamycin, neomycin, and streptomycin, a remarkable and gradual increase of the toxicity was detected at lower salinities. Thirdly, the highest heterogeneity was found for the rest of antimicrobials assayed (trimethoprim, nalidixic acid, spectinomycin, and tetracycline), where the effect of salinity was moderate and dependent on both the individual strain and the antimicrobial tested. The data presented here should facilitate genetic studies on moderate halophiles. Thus, they simplify the design of selection media for genetic exchange experiments. Besides, by using low-salinity media, genes encoding resistance to a number of antimicrobials, especially to aminoglycosides, can be used as genetic markers for plasmids or transposons to be transferred to these extremophiles.

Transposon mutagenesis in halophilic eubacteria: conjugal transfer and insertion of transposon Tn5 and Tn1732 in Halomonas elongata.

Molecular genetic studies of halophilic eubacteria have been limited by the lack of a suitable method for mutagenesis. To overcome this, we established a transposon mutagenesis procedure for the ectoine-producing, halophilic bacterium Halomonas elongata. We used suicide plasmids pSUP101 and pSUP102-Gm to introduce the transposons Tn5 and Tn1732 respectively into H. elongata via Escherichia coli SM10 mediated conjugation. Our finding that H. elongata is sensitive to aminoglycoside antibiotics at low salinity enabled us to apply transposons that mediate kanamycin resistance. The insertions of transposon Tn1732 occurred at different sites in the chromosome of H. elongata, as proved by Southern hybridization analysis. Phenotypic analysis revealed that different auxotrophic and salt sensitive mutants were generated by mutagenesis with transposon Tn1732. To our knowledge this is the first report of a successful application of a transposon for direct generalized mutagenesis in a halophilic eubacterium.

[The behavior of polycyclic aromatic hydrocarbons in soil fertilized with sewage sludge-garbage compost. I. Field studies]. / Das Verhalten von polyzyklischen, aromatischen Kohlenwasserstoffen (PAK) in mit Müll-Klärschlamm-Kompost gedüngten Böden. I. Freilanduntersuchungen.

Sewage sludge-garbage composts which are used as soil conditioners usually contain high concentrations of PAH. A risk for human health could arise if the use of such composts leads to high concentrations of PAH in the soil and these are taken up by plants for human consumption. We investigated the fate of PAH introduced into the soil with sewage sludge-garbage compost and the possible association with the microbial flora. Field investigations in wineyards during more than 18 months showed no reduction of PAH in the soil. There was no seasonal variation and no correlation between microbial data and PAH concentrations in the wineyards treated with compost or untreated. From these findings it must be concluded that under natural conditions PAH persist in the soil for a long time and are not taken up by plants to an appreciable extent.

[The behavior of polycyclic aromatic hydrocarbons in soil fertilized with sewage sludge-garbage compost. II. Laboratory studies]. / Das Verhalten von polyzyklischen, aromatischen Kohlenwasserstoffen (PAK) in mit Müll-Klärschlamm-Kompost gedüngten Böden. II. Laborversuche.

The possible destruction in the soil of PAH present in sewage sludge-garbage composts in considerable amounts has been studied under various conditions. Sandy and loamy soil were mixed with the compost and kept in a climate chamber at 20 degrees C, 25 degrees C and 28 degrees C with 30% and 80% relative moisture. One part of the samples was illuminated the other kept in the dark. Control samples with and without compost were sterilized. PAH determinations, bacterial counts on Moutonagar and counts of the actinomycetes were carried out in regular intervals. No influence of temperature, moisture or light could be demonstrated under the experimental conditions. No difference in the behaviour of PAH concentrations in sterilized and nonsterilized soil samples during the periods of experiment, no increase or decrease of PAH were found. There was no correlation between bacterial counts and PAH concentrations. The laboratory experiments confirmed the results of the field investigations.

[Polycyclic aromatic hydrocarbons in agricultural soil (author's transl)]. / Polyzyklische, aromatische Kohlenwasserstoffe in landwirtschaftlich genutzten Böden.

The discussion about the possible consequences from the agricultural use of composted sewage sludge; which contains considerable amounts of polycyclic, aromatic hydrocarbons (PAH), caused us to investigate the normal concentrations of these substances in soil from agricultural land. In 50 soil samples, mainly from various parts of the Federal Republic of Germany the following 6 PAH were determined: fluoranthene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, benzo(ghi)perylene, indeno(1.2.3-cd)pyrene. In 74% of the samples benzopyrene concentration was between 2 and 50 microgram/kg, and the sum of the 6 compounds between 50 and 500 microgram/kg. No smaller values were found, and higher concentrations in most cases could be connected to some source of pollution.

[The determination of phenols in water: gas chromatographic identification by means of the electron affinity (author's transl)]. / Untersuchungen zur Bestimmung von Phenolen im Wasser: gaschromatographische Identifizierung auf Grund des Elektronenanlagerungsvermögens

The electron affinities for 98 phenolic compounds have been determined using an electron capture detector (ECD) and a flame ionisation detector (FID). The signals of the two detectors were registered simultanously on a two channel recorder by splitting the gas stream at the column outlet for the ECD and the FID (1:1). The peak areas were corrected for equal concentration and instrument parameters and the relation peak area (ECD)/peak area (FID) was used as a measure of electron affinity. The values thus measured are given in a table. Among the phenolics found in water there are several groups with high or very high electron affinity, e.g. dichlorophenols, trichlorophenols, tetra- and pentachlorophenol; the values of these compounds are about 10(2), 10(3), 10(4), and 3 times 10(4) times higher, respectively, than that of phenol itself and its alkyl derivatives. For the mono- and dinitrophenols the corresponding figures are between 10(2) (o-nitrophenol) and 5 times 10(3) (dinitrophenols). A comparatively high value was measured for salicylic aldehyde: about 2.5 times 10(2) compared with phenol. The application of these values in the identification of some peaks in the gas chromatogram of a river water extract is demonstrated.