Morphological and Glucose Metabolism Abnormalities in Alcoholic Korsakoff's Syndrome: Group Comparisons and Individual Analyses

Background

Gray matter volume studies have been limited to few brain regions of interest, and white matter and glucose metabolism have received limited research attention in Korsakoff''s syndrome (KS). Because of the lack of brain biomarkers, KS was found to be underdiagnosed in postmortem studies.

Methodology/Principal Findings

Nine consecutively selected patients with KS and 22 matched controls underwent both structural magnetic resonance imaging and ¹⁸F-fluorodeoxyglucose positron emission tomography examinations. Using a whole-brain analysis, the between-group comparisons of gray matter and white matter density and relative glucose uptake between patients with KS and controls showed the involvement of both the frontocerebellar and the Papez circuits, including morphological abnormalities in their nodes and connection tracts and probably resulting hypometabolism. The direct comparison of the regional distribution and degree of gray matter hypodensity and hypometabolism within the KS group indicated very consistent gray matter distribution of both abnormalities, with a single area of significant difference in the middle cingulate cortex showing greater hypometabolism than hypodensity. Finally, the analysis of the variability in the individual patterns of brain abnormalities within our sample of KS patients revealed that the middle cingulate cortex was the only brain region showing significant GM hypodensity and hypometabolism in each of our 9 KS patients.

Conclusions/Significance

These results indicate widespread brain abnormalities in KS including both gray and white matter damage mainly involving two brain networks, namely, the fronto-cerebellar circuit and the Papez circuit. Furthermore, our findings suggest that the middle cingulate cortex may play a key role in the pathophysiology of KS and could be considered as a potential in vivo brain biomarker.     

Die Dolipore der Basidiomyceten

Zusammenfassung Bei den Doliporen einiger Basidiomyceten sind weitere Differenzierungen bekannt geworden. 1. Der Porenkanal kann durch 1–3 Membranen oder durch Pfropfen verschlossen werden. 2. Das Parenthesom ist von einem ribosomenreichen Material bedeckt, das durch endoplasmatisches Reticulum vom übrigen Cytoplasma abgegrenzt wird. Diese Abßenkappe kontrolliert vielleicht den Stofftransport.

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The dolipore of the basidiomycetes

Summary Using electron microscopy, more details have been found in the fine structure of dolipores in some basidiomycetes: 1. The pore channel may be closed by 1–3 membranes or plugs. 2. The parenthesome is covered by large plugs of material rich in ribosomes which is separated from the cytoplasm by endoplasmic reticulum. It is suggested that this outer cap controls the intercellular transport.

     

Plasmid-determined resistance to arsenic and antimony inPseudomonas aeruginosa

Resistance to arsenic salts in aPseudomonas aeruginosa clinical isolate was shown to be determined by a 100 kb transferable plasmid. The resistance pattern included arsenate, arsenite, and antimonate ions. Arsenate and arsenite resistances were inducible by previous exposure of cultures to subinhibitory amounts of either of the two ions. Phosphate ions protectedP. aeruginosa cells from the toxic effects of arsenate but did not alter arsenite toxicity.     

Indigenous bacteria with antagonistic and plant-growth-promoting activities improve slow-filtration efficiency in soilless cultivation

In tomato soilless culture, slow filtration allows one to control the development of diseases caused by pathogenic microorganisms. During the disinfecting process, microbial elimination is ensured by mechanical and biological factors. In this study, system efficacy was enhanced further to a biological activation of filter by inoculating the pozzolana grains contained in the filtering unit with 5 selected bacteria. Three strains identified as Pseudomonas putida and 2 as Bacillus cereus came from a filter whose high efficiency to eliminate pathogens has been proven over years. These 5 bacteria displayed either a plant growth promoting activity (P. putida strains) or antagonistic properties (B. cereus strains). Over the first months following their introduction in the filter, the bacterial colonisation of pozzolana grains was particularly high as compared to the one observed in the control filter. Conversely to Bacillus spp. populations, Pseudomonas spp. ones remained abundant throughout the whole cultural season. The biological activation of filter unit very significantly enhanced fungal elimination with respect to the one displayed by the control filter. Indeed, the 6-month period needed by the control filter to reach its best efficacy against Fusarium oxysporum was shortened for the bacteria-amended filter; in addition, a high efficacy filtration was got as soon as the first month. Fast colonization of pozzolana grains by selected bacteria and their subsequent interaction with F. oxysporum are likely responsible for filter efficiency. Our results suggest that Pseudomonas spp. act by competition for nutrients, and Bacillus spp. by antibiosis and (or) direct parasitism. Elimination of other fungal pathogens, i.e., Pythium spp., seems to differ from that of Fusarium since both filters demonstrated a high efficacy at the experiment start. Pythium spp. elimination appears to mainly rely on physical factors. It is worth noting that a certain percentage of the 5 pozzolana-inoculated bacteria failed to colonise the filter unit and were, thus, driven to the plants by the nutrient solution. Their contribution to the establishment of a beneficial microbial community in the rhizosphere is discussed.     

Physical and functional interaction of the Arabidopsis K(+) channel AKT2 and phosphatase AtPP2CA

The AKT2 K(+) channel is endowed with unique functional properties, being the only weak inward rectifier characterized to date in Arabidopsis. The gene is expressed widely, mainly in the phloem but also at lower levels in leaf epiderm, mesophyll, and guard cells. The AKT2 mRNA level is upregulated by abscisic acid. By screening a two-hybrid cDNA library, we isolated a protein phosphatase 2C (AtPP2CA) involved in abscisic acid signaling as a putative partner of AKT2. We further confirmed the interaction by in vitro binding studies. The expression of AtPP2CA (beta-glucuronidase reporter gene) displayed a pattern largely overlapping that of AKT2 and was upregulated by abscisic acid. Coexpression of AtPP2CA with AKT2 in COS cells and Xenopus laevis oocytes was found to induce both an inhibition of the AKT2 current and an increase of the channel inward rectification. Site-directed mutagenesis and pharmacological analysis revealed that this functional interaction involves AtPP2CA phosphatase activity. Regulation of AKT2 activity by AtPP2CA in planta could allow the control of K(+) transport and membrane polarization during stress situations.     

Synthesis,spectral studies,DNA binding,photocleavage, antimicrobial and anticancer activities of isoindol Ru(II) polypyridyl complexes

Abstract

Three new Ru(II) polypyridyl complexes [Ru(phen)₂CIIP]²⁺ (1) {CIIP = 2-(5-Chloro-3a H-Isoindol-3-yl)-1H-Imidazo[4,5-f][1, 10]phenantholine} (phen = 1, 10 phenanthroline), [Ru(bpy)₂CIIP]²⁺ (2) (bpy = 2, 2′ bipyridine) and [Ru(dmb)₂CIIP]²⁺ (3) (dmb = 4, 4′-dimethyl 2, 2′ bipyridine) were synthesized and characterized by different spectral methods. The DNA-binding behavior of these complexes was investigated by absorption, emission spectroscopic titration and viscosity measurements, indicating that these three complexes bind to CT-DNA in an intercalative mode, but binding affinities of these complexes were different. The DNA-binding constants K_b of complexes 1, 2 and 3 were calculated in the order of 10⁶. All three complexes cleave pBR322 DNA in photoactivated cleavage studies and exhibit good antimicrobial activity. Anticancer activity of these Ru(II) complexes was evaluated in MCF7 cells. Cytotoxicity by MTT assay showed growth inhibition in a dose dependent manner. Cell cycle analysis by flow cytometry data showed an increase in Sub G1 population. Annexin V FITC/PI staining confirms that these complexes cause cell death by the induction of apoptosis.     

New hyalellids (Crustacea, Amphipoda, Hyalellidae) from Lake Titicaca

Two new species of hyalellid amphipods, Hyalella crawfordi and H. gauthieri, are described from Lake Titicaca; H. echinus (Faxon, 1876) is redescribed. The H. echinus group of species is newly proposed for these three species, and a group diagnosis is provided. A key to the three species in the group is provided Full article published online at http://www.senckenberg.de/odes/06-10.htm.     

Comparison of various BCG preparations in the EORTC — ICIG experimental screening for systemic immunity adjuvants applicable to cancer immunotherapy

Summary Nine lyophilized, five frozen, and one fresh BCG preparation from various sources were tested for their activity as adjuvants of systemic immunity in mice. Using three tests, the IgM response to sheep red blood cells, immunoprophylaxis of L1210 leukemia, and immunoprophylaxis of Lewis tumor, results consistent with both immunostimulation and immunodepression were observed, varying as a function of the BCG strain, its storage conditions, and the assay used. Only fresh Pasteur strain BCG was effective in all three tests; its activity was modified by lyophilization and by freezing. Possible reasons for the superiority of fresh Pasteur BCG as an adjuvant are discussed.European Organization for Research and Treatment of CancerInstitut de Cancérologie et d'Immunogénétique     

Spontaneous hybridization between a male-sterile oilseed rape and two weeds

Spontaneous interspecific hybrids were produced under natural conditions (pollination by wind and bees) between a male-sterile cybrid Brassica napus (AACC, 2n = 38) and two weeds Brassica adpressa (AdAd, 2n = 14) and Raphanus raphanistrum (RrRr, 2n = 18). After characterization by chromosome counts and isozyme analyses, we observed 512 and 3 734 inter-specific seeds per m² for the B. napus-B. adpressa and B. napus-R. raphanistrum trials respectively. Most of the hybrids studied had the expected triploid structure (ACX). In order to quantify the frequency of allosyndesis between the genomes involved in the hybrids, their meiotic behavior was compared to a haploid of B. napus (AC). For the B. napus-B. adpressa hybrids, we concluded that probably no allosyndesis occurred between the two parental genomes, and that genetic factors regulating homoeologous chromosome pairing were carried by the B. adpressa genome. For the B. napus-R. raphanistrum hybrids, high chromosome pairing and the presence of multivalents (in 9.16% of the pollen mother cells) indicate that recombination is possible between chromosomes of different genomes. Pollen fertility of the hybrids ranged from 0 to 30%. Blackleg inoculation tests were performed on the three parental species and on the interspecific hybrids. BC₁ production with the weeds and with rapeseed was attempted. Results are discussed in regard to the risk assessment of transgenic rapeseed cultivation, F₁ hybrid rapeseed variety production, and rapeseed improvement.     

A Comparative Structure–Function Analysis and Molecular Mechanism of Action of Endonucleases from Serratia marcescens and Physarum polycephalum

Structural and functional characteristics were compared for wild-type nuclease from Serratia marcescens, which belongs to the family of DNA/RNA nonspecific endonucleases, its mutational forms, and the nuclease I-PpoI from Physarum polycephalum, which is a representative of the Cys-His box-containing subgroup of the superfamily of extremely specific intron-encoded homing DNases. Despite the lack of sequence homology and the overall different topology of the Serratia marcescens and I-PpoI nucleases, their active sites have a remarkable structural similarity. Both of them have a unique magnesium atom in the active site, which is a part of the coordinatively bonded water–magnesium complex involved in their catalytic acts. In the enzyme–substrate complexes, the Mg²⁺ ion is chelated by an Asp residue, coordinates two oxygen atoms of DNA, and stabilizes the transition state of the phosphate anion and 3"-OH group of the leaving nucleotide. A new mechanism of the phosphodiester bond cleavage, which is common for the Serratia marcescens and I-PpoI nucleases and differs from the known functioning mechanism of the restriction and homing endonucleases, was proposed. It presumes a His residue as a general base for the activation of a non-cluster water molecule at the nucleophilic in line displacement of the 3"-leaving group. A strained metalloenzyme–substrate complex is formed during hydrolysis and relaxes to the initial state after the reaction.