Heterogeneous nuclear ribonucleoprotein A3, a novel RNA trafficking response element-binding protein

The cis-acting response element, A2RE, which is sufficient for cytoplasmic mRNA trafficking in oligodendrocytes, binds a small group of rat brain proteins. Predominant among these is heterogeneous nuclear ribonucleoprotein (hnRNP) A2, a trans-acting factor for cytoplasmic trafficking of RNAs bearing A2RE-like sequences. We have now identified the other A2RE-binding proteins as hnRNP A1/A1(B), hnRNP B1, and four isoforms of hnRNP A3. The rat and human hnRNP A3 cDNAs have been sequenced, revealing the existence of alternatively spliced mRNAs. In Western blotting, 38-, 39-, 41 -, and 41.5-kDa components were all recognized by antibodies against a peptide in the glycine-rich region of hnRNP A3, but only the 41- and 41.5-kDa bands bound antibodies to a 15-residue N-terminal peptide encoded by an alternatively spliced part of exon 1. The identities of these four proteins were verified by Edman sequencing and mass spectral analysis of tryptic fragments generated from electrophoretically separated bands. Sequence-specific binding of bacterially expressed hnRNP A3 to A2RE has been demonstrated by biosensor and UV cross-linking electrophoretic mobility shift assays. Mutational analysis and confocal microscopy data support the hypothesis that the hnRNP A3 isoforms have a role in cytoplasmic trafficking of RNA

Study of fever in patients with acute stroke

Fever is a common medical complication in patients with acute stroke and its presence has been associated with poor outcome. Although, the most frequent etiology of fever is an infectious process, a focus of infection cannot be often identified and it is thus attributed to the cerebral lesion itself (fever of central origin). The aim of our study was to evaluate the effect of fever on stroke outcome and to define the specific characteristics that influence the prognosis. We also investigated whether serum procalcitonin (PCT) and C-reactive protein (CRP) levels could be used as markers of infection in feverescent patients. The presence of fever was found to be an independent predictor for having ΒI score 80 years), early onset of fever (80 ετών), η πρώιμη εμφάνιση πυρετού (<24h), ο τύπος του Α.Ε.Ε. (η ενδοεγκεφαλική αιμορραγία και το καρδιοεμβολικό είχαν τη χειρότερη πρόγνωση) και η συνδυασμένη νοσηλεία στη μονάδα Α.Ε.Ε. και τον κοινό θάλαμο. Επιπλέον, δείξαμε ότι η προκαλσιτονίνη ορού μπορεί να χρησιμοποιηθεί σαν δείκτης διάγνωσης του πυρετού λοιμώδους αιτιολογίας στους ασθενείς με Α.Ε.Ε., αφού τα επίπεδα της δεν σχετίζονται με την ηλικία του ασθενούς, το επίπεδο συνείδησης και τη νευρολογική βλάβη κατά την εισαγωγή σε αντίθεση με τα επίπεδα της CRP. Συμπερασματικά, η μελέτη μας έδειξε πως η παρουσία του πυρετού στο Α.Ε.Ε. επιδεινώνει την αποκατάσταση των ασθενών και ότι η PCT ορού μπορεί να χρησιμοποιηθεί για τη διαφοροδιάγνωση του πυρετού λοιμώδους έναντι του πυρετού κεντρικής αιτιολογίας

Molecular characterization of a murine, major A/B type hnRNP protein: mBx

Journal URL: http://www.sciencedirect.com/science/journal/0167478

Aetiology of fever in patients with acute stroke

Objective. Fever in patients with acute stroke is usually related to infectious complications. In some cases, a focus of infection cannot be identified, fever does not respond to empirical antibiotic treatment: and is thought to be due to the central nervous system lesion. The aim of this study was to determine the frequency and origin of fever in patients with acute stroke and the characteristics associated with the presence of fever. Design. A retrospective study of 36 months’ duration. Setting. The study was carried out at ‘Alexandra’ Hospital, a tertiary care teaching centre in Athens, Greece. Subjects. A total of 330 patients hospitalized for acute stroke from June 1992 until July 1994. Results. In 37.6% of 330 patients, fever was noted; 22.7% had a documented infection and 14.8% had fever without a documented infection. In univariate analysis, older age was associated with the presence of fever (P = 0.001). The development of fever was associated with intracerebral haemorrhage versus ischaemic infarct (P &lt; 0.001) and with the presence of mass effect (P &lt; 0.001), transtentorial herniation (P &lt; 0.001), intraventricular blood (P &lt; 0.001), and larger size of ischaemic infarct (P = 0.0001) and of haemorrhage (P = 0.0002). Patients with fever had lower scores on admission on the Glasgow Coma Scale (P = 0.0001) and the Scandinavian Stroke Scale (P = 0.0001). The development of fever was associated with prior use of an invasive technique (P &lt; 0.001) and more specifically with urinary catheterization (P &lt; 0.001), but not with the presence of risk factors for infection. Patients with fever had a worse outcome assessed by the Modified Rankin Scale (P = 0.0001) and the Barthel Index (P = 0.0001). In multivariate analysis, age, Scandinavian Stroke Scale score and mass effect were found to be significantly associated with fever (P = 0.035, P = 0.0001 and P = 0.0004, respectively). Patients with fever without documented infection had an earlier onset of fever than those with infection (P = 0.0061). In a logistic regression analysis, tl-le only factor predictive of fever without documented infection versus infection was earlier onset of fever (P = 0.029). Conclusion. Patients with acute stroke who develop fever are older, suffer severe stroke, their fever is associated with the use of invasive techniques, and they have a poor outcome. In patients with fever without a focus of infection, the only characteristic that is different from patients with known infection is earlier onset of fever

Recognition of subsets of the mammalian A/B-type core heterogeneous nuclear ribonucleoprotein polypeptides by novel autoantibodies

This is also available in PubMed Central at: http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1217995Journal URL: http://www.biochemj.org/bj/default.ht

Recognition of subsets of the mammalian A/B-type core heterogeneous nuclear ribonucleoprotein polypeptides by novel autoantibodies.

The structurally related A/B-type core heterogeneous nuclear ribonucleoprotein (hnRNP) polypeptides of 34-39 kDa (A1, A2, B1 and B2) belong to a family of RNA-binding proteins that are major components of 40 S hnRNP complexes. By two-dimensional gel electrophoresis and peptide mapping analysis we compared each member of the A/B-type core proteins in the human and rat liver cells. This comparison revealed the unique presence in rat cells of major protein species, referred to as mBx polypeptides, that appeared as three charge isoforms at a position corresponding to the minor HeLa B1b protein spot. In addition, clear differences in the ratios of the A1 polypeptide to the A1b isoform were observed. The detection, in sera of patients with rheumatic autoimmune diseases, of two novel autoantibody specificities, one recognizing solely B2 protein and the second both the B2 and mBx polypeptides, helped to identify mBx proteins as new A/B-type hnRNP components, immunologically related to B2 protein. A common immunoreactive V8 protease peptide of approx. 17 kDa has been identified in B2 and mBx hnRNP polypeptides. mBx protein species are identified in cells of murine origin, and have a ubiquitous tissue distribution and developmental appearance