DIFFERENT AQUAPORIN-4 EXPRESSION IN GLIOBLASTOMA MULTIFORME PATIENTS WITH AND WITHOUT SEIZURES

Aquaporin-4 (AQP-4), the most important water channel in the brain, is expressed by astrocyte endfeet abutting microvessels. Altered expression levels of AQP-4 and redistribution of the protein throughout the membranes of cells found in glioblastoma multiforme (GBM) lead to development of the oedema often found surrounding the tumour mass. Dysregulation of AQP-4 also occurs in hippocampal sclerosis and cortical dysplasia in patients with refractory partial epilepsy. This work reports on analysis of the relationship between AQP-4 expression and the incidence of epileptic seizures in patients with GBM. Immunohistochemical and PCR techniques were used to evaluate AQP-4 in biopsy specimens from 19 patients with GBM, 10 of whom had a history of seizures prior to surgery. AQP-4 mRNA levels were identical in the two groups of patients, but AQP-4 expression was more frequently detected on the GBM membranes from specimens of patients with seizures than from those without (10 vs. 2,

Five-year follow-up of secondary iris-claw intraocular lens implantation for the treatment of aphakia: Anterior chamber versus retropupillary implantation

Background Though several procedures of IOL implantation have been described (sutured scleral fixation, intra-scleral fixation, angle-supported anterior chamber, and anterior chamber or retropupillary iris-claw IOLs), there are no randomized trials which are comparing different techniques. Hence, the surgical treatment of aphakia still remains controversial and challenging. The purpose of this study was to compare the long-term efficacy and the rate of complications of anterior versus posterior Iris-claw intraocular lenses (IOL) implantation to correct for the treatment of aphakia without sufficient capsule support. Methods and findings Consecutive eyes having secondary implantation of aphakic iris-fixated IOLs with a followup of at least 5 years were considered. Mean correct distance visual acuity (CDVA) changes, percentage of eyes with CDVA improvement, mean corneal endothelial cell density (CECD) loss and the rate of other complications were used for statistical analysis. The study evaluated a total of 180 eyes (Group A: 87 anterior chamber iris-claw fixation, Group B: 93 retropupillary iris-claw implantation) of 180 consecutive different patients, with aphakia of various reasons. CDVA improved significantly in both groups after surgery (P<0.001, ANOVA), and was remarkably higher than baseline in both groups from first week and during the entire follow-up (P<0.001, Tukey’s Honest Significant Difference). There was no statistically significant difference in CDVA between the two groups during each follow-up visits (P = NS, unpaired t-test) and in the CDVA improvement percentage between the two groups (P = 0.882, Chi-square test). No significant changes in CECD were noted after surgery in both groups (ANOVA Group A: P = 0.067, Group B: P = 0.330P). No intra-operative complications occurred in both groups. There was no statistically significant difference in the rate of complications between the two groups (P = NS, Chi-square test), except for pigment precipitates which were higher in Group A (P<0.05, Chi-square test). Conclusions Five-year follow-up shows that secondary implantation of aphakic IOLs is effective and safe for the correction treatment of aphakia in eyes without capsule support

Photosynthetic growth despite a broken Q-cycle

Central in respiration or photosynthesis, the cytochrome bc1 and b6f complexes are regarded as functionally similar quinol oxidoreductases. They both catalyse a redox loop, the Q-cycle, which couples electron and proton transfer. This loop involves a bifurcated electron transfer step considered as being mechanistically mandatory, making the Q-cycle indispensable for growth. Attempts to falsify this paradigm in the case of cytochrome bc1 have failed. The rapid proteolytic degradation of b6f complexes bearing mutations aimed at hindering the Q-cycle has precluded so far the experimental assessment of this model in the photosynthetic chain. Here we combine mutations in Chlamydomonas that inactivate the redox loop but preserve high accumulation levels of b6f complexes. The oxidoreductase activity of these crippled complexes is sufficient to sustain photosynthetic growth, which demonstrates that the Q-cycle is dispensable for oxygenic photosynthesis

Global conformal anomaly in N=2 string

We show the existence of a global anomaly in the one-loop graphs of N=2 string theory, defined by sewing tree amplitudes, unless spacetime supersymmetry is imposed. The anomaly is responsible for the non-vanishing maximally helicity violating amplitudes. The supersymmetric completion of the N=2 string spectrum is formulated by extending the previous cohomological analysis with an external spin factor; the target space-time spin-statistics of these individual fields in a selfdual background are compatible with previous cohomological analysis as fields of arbitrary spin may be bosonized into one another. We further analyze duality relations between the open and closed string amplitudes and demonstrate this in the supersymmetric extension of the target space-time theory through the insertion of zero-momentum operators.Comment: 29 pages, LaTeX, one figur

Deinococcus geothermalis: The Pool of Extreme Radiation Resistance Genes Shrinks

Bacteria of the genus Deinococcus are extremely resistant to ionizing radiation (IR), ultraviolet light (UV) and desiccation. The mesophile Deinococcus radiodurans was the first member of this group whose genome was completely sequenced. Analysis of the genome sequence of D. radiodurans, however, failed to identify unique DNA repair systems. To further delineate the genes underlying the resistance phenotypes, we report the whole-genome sequence of a second Deinococcus species, the thermophile Deinococcus geothermalis, which at its optimal growth temperature is as resistant to IR, UV and desiccation as D. radiodurans, and a comparative analysis of the two Deinococcus genomes. Many D. radiodurans genes previously implicated in resistance, but for which no sensitive phenotype was observed upon disruption, are absent in D. geothermalis. In contrast, most D. radiodurans genes whose mutants displayed a radiation-sensitive phenotype in D. radiodurans are conserved in D. geothermalis. Supporting the existence of a Deinococcus radiation response regulon, a common palindromic DNA motif was identified in a conserved set of genes associated with resistance, and a dedicated transcriptional regulator was predicted. We present the case that these two species evolved essentially the same diverse set of gene families, and that the extreme stress-resistance phenotypes of the Deinococcus lineage emerged progressively by amassing cell-cleaning systems from different sources, but not by acquisition of novel DNA repair systems. Our reconstruction of the genomic evolution of the Deinococcus-Thermus phylum indicates that the corresponding set of enzymes proliferated mainly in the common ancestor of Deinococcus. Results of the comparative analysis weaken the arguments for a role of higher-order chromosome alignment structures in resistance; more clearly define and substantially revise downward the number of uncharacterized genes that might participate in DNA repair and contribute to resistance; and strengthen the case for a role in survival of systems involved in manganese and iron homeostasis

Exploring the anatomy of negative motor areas (NMAs): Findings in awake surgery

Positive motor responses have been used in neurosurgery for the identification of motor structures. With the term “negative motor responses” (NMRs) a complete inhibition of movement without loss of muscle tone or consciousness is meant. Papers already exist in the literature regarding cortical areas in which such NMRs are evoked, the so-called “negative motor areas” (NMAs), but their location and functional meaning are still poorly understood. This paper discusses the anatomy of the NMAs of the human brain, in light of our brain mapping experience. 21 patients underwent awake surgery and direct electrical stimulation (DES) was performed using bipolar electrodes. Excision was interrupted when functional responses were intraoperatively identified through DES. The labeled mapping sites were recorded by photography prior to and following tumor resection. Results depicting a probabilistic map of negative motor network anatomy were retrospectively analyzed. Our findings strongly support the fact that the precentral gyrus, classical site of the of the Primary Motor Areas, is also strongly involved in generating NMRs. The distribution of NMAs was noted not to be as rigid as previously described, ranging in different brain areas with a somatotopic arrangement. Presented anatomical results are consistent with the literature, but the exact functional meaning of NMAs and their subcortical connectivity is still far from being completely understood

An optical coherence tomography-based grading of diabetic maculopathy proposed by an international expert panel: The European School for Advanced Studies in Ophthalmology classification

To present an authoritative, universal, easy-to-use morphologic classification of diabetic maculopathy based on spectral domain optical coherence tomography

Noncoupled NADH:Ubiquinone Oxidoreductase of Azotobacter vinelandii Is Required for Diazotrophic Growth at High Oxygen Concentrations

The gene encoding the noncoupled NADH:ubiquinone oxidoreductase (NDH II) from Azotobacter vinelandii was cloned, sequenced, and used to construct an NDH II-deficient mutant strain. Compared to the wild type, this strain showed a marked decrease in respiratory activity. It was unable to grow diazotrophically at high aeration, while it was fully capable of growth at low aeration or in the presence of NH(4)(+). This result suggests that the role of NDH II is as a vital component of the respiratory protection mechanism of the nitrogenase complex in A. vinelandii. It was also found that the oxidation of NADPH in the A. vinelandii respiratory chain is catalyzed solely by NDH II