Photometric structure of the peculiar galaxy ESO 235-G58

We present the near-infrared and optical properties of the peculiar galaxy ESO 235-G58, which resembles a late-type ringed barred spiral seen close to face-on. However, the apparent bar of ESO 235-G58 is in reality an edge-on disk galaxy of relatively low luminosity. We have analyzed the light and color distributions of ESO 235-G58 in the NIR and optical bands and compared them with the typical properties observed for other morphological galaxy types, including polar ring galaxies. Similar properties are observed for ESO 235-G58, polar ring galaxies, and spiral galaxies, which leads us to conclude that this peculiar system is a polar-ring-related galaxy, characterized by a low inclined ring/disk structure, as pointed out by Buta & Crocker in an earlier study, rather than a barred galaxy.Comment: 16 pages, 15 figures, accepted for publication in Astronomy & Astrophysic

Phenotypic effects of expanded ataxin-1 polyglutamines with interruptions in vitro

Spinocerebellar ataxia type 1 is a neurodegenerative disease caused by expansion of an uninterrupted glutamine repeat in ataxin-1 protein. Protein aggregation and immunoreactivity to 1C2 monoclonal antibody are two distinct pathognomonic features of expanded ataxin-1, as well as of other polyglutamine disorders. Rare cases of non-affected elderly subjects carrying expanded ataxin-1 alleles were found in random population. However, in these alleles the glutamine stretch was interrupted by histidines. Due to lack of phenotype, these alleles should be considered "normal". Most importantly, occurrence of these unusual alleles provides a unique opportunity to investigate which molecular properties of expanded ataxin-1 are not coupled to polyglutamine pathogenesis. Towards this goal, we compared in vitro the immunoreactivity to 1C2 antibody and the ability to form aggregates of interrupted and uninterrupted alleles. Immunoblotting showed that expanded-interrupted ataxin-1 had an affinity to 1C2 resembling that of normal ataxin-1. On the contrary, filter assay showed that aggregation rate of expanded-interrupted ataxin-1 resembles that of expanded-uninterrupted ataxin-1. These observations indicate that affinity for 1C2 does not directly correlate with self-aggregation of ataxin-1. Moreover, self-aggregation is not directly affected by histidine interruptions. In conclusion, these results support the hypothesis that mechanisms underlying neuronal degeneration are triggered by protein misfolding rather than by protein aggregation

Orthostatic intolerance and autonomic dysfunction following bariatric surgery: A retrospective study and review of the literature

The prevalence and costs of the obesity epidemic and obesity-related conditions, including diabetes mellitus, is consistently increasing worldwide. Bariatric medicine is attempting to address this with weight loss and exercise programmes, and with increasing frequency, various forms of bariatric surgery. There has been considerable success reported after bariatric surgery but not without. We describe 14 patients with orthostatic intolerance (OI) post bariatric surgery. We report on OI (postural dizziness, palpitations and fainting), the results of cardiovascular autonomic testing and the associated and/or causative findings as well as reviewing the literature to consider the possible mechanisms. Comprehensive autonomic testing revealed that 35.7% (Buchwald et al., 2004) of these patients fulfilled the criteria for the Postural Tachycardia Syndrome (PoTS), 57.1% (Cremieux et al., 2008) had low levels of basal BP and 42.9% (Cammisotto & Bendayan, 2007) patients were presyncopal and 14.3% (Billakanty et al., 2008) experienced syncope. We propose that the incidence of OI post-bariatric surgery is higher than considered, that certain cohorts may be more susceptible to complications, and that further research is needed to identify the prevalence and, ideally anticipate occurrence. With the increasing prevalence of obesity and required clinical interventions, further understanding of the pathophysiological processes causing autonomic dysfunction after bariatric interventions will aid management, which may differ in those with an underlying disposition to autonomic involvement, such as diabetics, in whom such procedures are increasingly used

Ganglion cell complex analysis in glaucoma patients: what can it tell us?

Glaucoma is a group of optic neuropathies characterized by a progressive degeneration of retina ganglion cells (RGCs) and their axons that precedes functional changes detected on the visual field. The macular ganglion cell complex (GCC), available in commercial Fourier-domain optical coherence tomography, allows the quantification of the innermost retinal layers that are potentially involved in the glaucomatous damage, including the retinal nerve fiber (RNFL), ganglion cell and inner plexiform layers. The average GCC thickness and its related parameters represent a reliable biomarker in detecting preperimetric glaucomatous damage. The most accurate GCC parameters are represented by average and inferior GCC thicknesses, and they can be associated with progressive visual field loss. Although the diagnostic accuracy increases with more severe glaucomatous damage and higher signal strength values, it is not affected by increasing axial length, resulting in a more accurate discrimination of glaucomatous damage in myopic eyes with respect to the traditional RNFL thickness. The analysis of the structure-function relationship revealed a good agreement between the loss in retinal sensitivity and GCC thickness. The use of a 10-2° visual field grid, adjusted for the anatomical RGCs displacement, describes more accurately the relationship between RGCs thickness and visual field sensitivity loss

Dramatically different levels of cacna1a gene expression between pre-weaning wild type and leaner mice

Loss of function mutations of the CACNA1A gene, coding for the α1A subunit of P/Q type voltage-gated calcium channel (Ca(V)2.1), are responsible for Episodic Ataxia type 2 (EA2), an autosomal dominant disorder. A dominant negative effect of the EA2 mutated protein, rather than a haploinsufficiency mechanism, has been hypothesised both for protein-truncating and missense mutations. We analysed the cacna1a mRNA expression in leaner mice carrying a cacna1a mutation leading to a premature stop codon. The results showed a very low mutant mRNA expression compared to the wild type allele. Although the mutant mRNA slightly increases with age, its low level is likely due to degradation by nonsense mediated decay, a quality control mechanism that selectively degrades mRNA harbouring premature stop codons. These data have implications for EA2 in humans, suggesting a haploinsufficiency mechanism at least for some of the CACNA1A mutations leading to a premature stop codon

Localization and genomic structure of human deoxyhypusine synthase gene on chromosome 19p13.2-distal 19p13.1

The amino acid hypusine is formed post-translationally in a single cellular protein, the eukaryotic translation initiation factor 5A, by two enzymes, namely deoxyhypusine synthase and deoxyhypusine hydroxylase. Hypusine is found in all eukaryotes and in some archaebacteria, but not in eubacteria. The deoxyhypusine synthase cDNA was cloned and mapped by fluorescence in situ hybridization on chromosome 19p13.11-p13.12. Rare cDNAs containing internal deletions were also found. We localized the deoxyhypusine synthase gene on a high resolution cosmid/BAC contig map of chromosome 19 to a region in 19p13.2-distal 19p13.1 between MANB and JUNB. Analysis of the genomic exon/intron structure of the gene coding region showed that it consists of nine exons and spans a length of 6.6kb. From observation of the genomic structure, it seems likely that the internally deleted forms of mature RNA are the result of alternative splicing, rather than of artifacts

Lower urinary tract dysfunction in Parkinsonian syndromes

Purpose of review: The aim of this review is to outline the clinical presentation, pathophysiology and evaluation of lower urinary tract (LUT) dysfunction in Parkinson’s disease and other parkinsonian syndromes including multiple system atrophy, dementia with Lewy bodies, progressive supranuclear palsy and corticobasal degeneration. // Recent findings: LUT dysfunction commonly occurs in neurological disorders, including patients with parkinsonian syndromes. The pattern of LUT dysfunction and its severity are variable, depending upon the site of lesion within the neural pathways. Parkinsonian syndromes are broadly divided into Parkinson’s disease (PD) and a typical parkinsonian syndromes such as multiple system atrophy (MSA), dementia with Lewy bodies (DLB), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). Different parkinsonian syndromes have distinct clinical features (e.g. dysautonomia, early dementia, supranuclear gaze palsy, higher cortical signs), and the pattern of LUT dysfunction and its severity can differ. // Conclusions: LUT dysfunction is a common feature in patients with parkinsonian syndromes. Recognising the pattern of LUT dysfunction during the assessment of these patients can help management and possibly facilitate an earlier diagnosis

The Halo Shape and Evolution of Polar Disc Galaxies

We examine the properties and evolution of a simulated polar disc galaxy. This galaxy is comprised of two orthogonal discs, one of which contains old stars (old stellar disc), and the other, containing both younger stars and the cold gas (polar disc) of the galaxy. By exploring the shape of the inner region of the dark matter halo, we are able to confirm that the halo shape is a oblate ellipsoid flattened in the direction of the polar disc. We also note that there is a twist in the shape profile, where the innermost 3 kpc of the halo flattens in the direction perpendicular to the old disc, and then aligns with the polar disc out until the virial radius. This result is then compared to the halo shape inferred from the circular velocities of the two discs. We also use the temporal information of the simulation to track the system's evolution, and identify the processes which give rise to this unusual galaxy type. We confirm the proposal that the polar disc galaxy is the result of the last major merger, where the angular moment of the interaction is orthogonal to the angle of the infalling gas. This merger is followed by the resumption of coherent gas infall. We emphasise that the disc is rapidly restored after the major merger and that after this event the galaxy begins to tilt. A significant proportion of the infalling gas comes from filaments. This infalling gas from the filament gives the gas its angular momentum, and, in the case of the polar disc galaxy, the direction of the gas filament does not change before or after the last major merger.Comment: Accepted for publication in MNRAS; 14 pages; 14 figure