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The hallmarks of chromosome organization in multicellular eukaryotes are chromosome territories (CT), chromatin compartments, and insulated domains, including topologically associated domains (TADs). Yet, most of these elements of chromosome organization are derived from analyses of a limited set of model organisms, while large eukaryotic groups, including insects, remain mostly unexplored. Here we combine Hi-C, biophysical modeling, and microscopy to characterize the 3D genome architecture of the silkmoth, Bombyx mori. In contrast to other eukaryotes, B. mori chromosomes form highly separated territories. Similar to other eukaryotes, B. mori chromosomes segregate into active A and inactive B compartments, yet unlike in vertebrate systems, contacts between euchromatic A regions appear to be a strong driver of compartmentalization. Remarkably, we also identify a third compartment, called secluded "S," with a unique contact pattern. Each S region shows prominent short-range self-contacts and is remarkably devoid of contacts with the rest of the chromosome, including other S regions. Compartment S hosts a unique combination of genetic and epigenetic features, localizes towards the periphery of CTs, and shows developmental plasticity. Biophysical modeling reveals that the formation of such secluded domains requires highly localized loop extrusion within them, along with a low level of extrusion in A and B. Our Hi-C data supports predicted genome-wide and localized extrusion. Such a broad, non-uniform distribution of extruders has not been seen in other organisms. Overall, our analyses support loop extrusion in insects and highlight the evolutionary plasticity of 3D genome organization, driven by a new combination of known processes.

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The hallmarks of chromosome organization in multicellular eukaryotes are chromosome territories (CT), chromatin compartments, and different types of domains, including topologically associated domains (TADs). Yet, most of these concepts derive from analyses of organisms with monocentric chromosomes. Here we describe the 3D genome architecture of an organism with holocentric chromosomes, the silkworm Bombyx mori . At the genome-wide scale, B. mori chromosomes form highly separated territories and lack substantial trans contacts. As described in other eukaryotes, B. mori chromosomes segregate into an active A and an inactive B compartment. Remarkably, we also identify a third compartment, Secluded "S", with a unique contact pattern. Compartment S shows strong enrichment of short-range contacts and depletion of long-range contacts. It hosts a unique combination of genetic and epigenetic features, localizes at the periphery of CTs and shows developmental plasticity. Biophysical modeling shows that formation of such secluded domains requires a new mechanism - a high density of extruded loops within them along with low level of extrusion and compartmentalization of A and B. Together with other evidence of loop extrusion in interphase, this suggests SMC-mediated loop extrusion in this insect. Overall, our analyses highlight the evolutionary plasticity of 3D genome organization driven by a new combination of known processes.

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BACKGROUND AND OBJECTIVE: In daily clinical practise, there is a lack of representative and robust data on the health-related quality of life (QoL) of patients with atrial fibrillation (AF). PARTICIPANTS AND METHOD: In the non-interventional MOVE study, 638 physicians (predominantly cardiologists) in ambulatory care (78.0% of all centres) or hospital-based (12.7%), documented prospectively and retrospectively data from 3354 consecutive patients with ECG-confirmed AF in the previous 12 months (mean age 68.9 +/- 10.1 years; 62.4% males, mean CHADS (2) score 1.9 +/- 1.3). 1136 (33.9%) had paroxysmal, 899 (26.8%) persistent and 1295 (38.6%) permanent AF. RESULTS: Symptoms within the previous 4 weeks were present in 89.9% of the cases and 43.1% of the patients reported palpitations in the range from sometimes to very frequently. As treatment aim, physicians reported rate control in 64%, rhythm control in 8%, and both in 19% of the cases (not stated: 8%). In the University of Toronto Atrial Fibrillation Severity Scale (AFSS), emergency room attendance or hospitalizations for AF or associated diseases in the previous 12 months were reported in 24.2% or 30.8%, respectively. Rhythm control was associated with higher emergency room admittance or hospitalization rates, respectively. The EQ-5D index (0.94 points) was near the maximum of 1; thus this index does not appear to reflect QoL of AF patients adequately. Analyses of the Visual Analogue Scale (VAS) of the EuroQol (EQ-5D), and the assessment scale or specific questions of AFSS, respectively, indicated an intermediate QoL or disease burden, respectively. No or only small differences were documented between subgroups with different AF types, or subgroups treated according to different aims. CONCLUSION: The great majority of AF patients had one or more recent AF symptoms, and their overall QoL was limited. In daily practise, rate control is not inferior to rhythm control in AF patients with respect to QoL.

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Twelve patients with insufficient transcranial Doppler signal underwent transcranial color-coded ultrasonography before and after administration of SH U 508A with different modes of administration. Clinically useful enhancement time after bolus injection was surpassed by that after standard infusion (1 mL/min), whereas further prolongation was observed after individualized infusion. Intravenous infusion of SH U 508A provides a prolonged useful enhancement compared with that after bolus injection.

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Although paradoxical embolism through a patent foramen ovale (PFO) has become an established cause of cerebral ischemia in younger patients without other obvious causes of stroke, the therapeutic options have not been investigated satisfactorily. There are still uncertainties about the natural history of PFO patients after suffering a stroke, and diagnostic criteria proving a causal and not incidental relation to the embolic event are not established. The stroke recurrence has been evaluated in several studies in a heterogeneous population and seems as low as 1.9% per year. Secondary prophylactic treatment has become a matter of discussion since efforts were made to close the PFO either surgically or by percutaneous transcatheter methods. Foramen closure seems to be effective in eliminating the mechanism of paradoxical embolism but its benefit-risk ratio has yet to be established. Following the goals of evidence-based medicine, none of the therapeutic options can be recommended. Fortunately, the issue has gone to trial and there are two studies underway to compare foramen closure to medical therapy.

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INTRODUCTION: A prospective, randomized and controlled trial is conducted to compare carotid endarterectomy and carotid stenting in high grade symptomatic carotid artery stenoses. METHODS: According to the study design symptomatic patients with a angiographically high-grade (> or = 70%) internal carotid artery stenosis are included. Pre- and postinterventional diagnostics during the hospitalization period includes neurological assessment, duplex sonography of the cervical and cerebral arteries and magnetic resonance imaging of the brain. Follow-up examinations are scheduled after 1, 6 and 12 months and consist of a neurological assessment and duplex sonography. After 12 months selective angiography and magnetic resonance imaging of the brain will be performed additionally. During a period of 9 months up to now 23/137 patients treated for a carotid artery stenosis were included in the study, 11 patients underwent surgery and 12 patients carotid stenting. RESULTS: Carotid stenting and endarterectomy was primarily successful without residual stenosis > 30% in each patient without the occurrence of stroke or death. In 18 follow-up examinations (neurological assessment including duplex sonography) of 13 patients (13 follow-up examinations after 30 days, 5 after 6 months) no relevant restenosis and no stroke occurred. CONCLUSION: As of yet, carotid stenting was a safe procedure. Due to the small number of patients a definitive conclusion can not be drawn.

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Calpain (Ca(2+)-dependent intracellular protease)-induced proteolysis has been considered to play a role in myoblast fusion to myotubes. We found previously that calpastatin (the endogenous inhibitor of calpain) diminishes transiently during myoblast differentiation. To gain information about the regulation of calpain and calpastatin in differentiating myoblasts, we evaluated the stability and synthesis of calpain and calpastatin, and measured their mRNA levels in L8 myoblasts. We show here that mu-calpain and m-calpain are stable, long-lived proteins in both dividing and differentiating L8 myoblasts. Calpain is synthesized in differentiating myoblasts, and calpain mRNA levels do not change during differentiation. In contrast, calpastatin (though also a long-lived protein in myoblasts), is less stable in differentiating myoblasts than in the dividing cells, and its synthesis is inhibited upon initiation of differentiation. Inhibition of calpastatin synthesis is followed by a diminution in calpastatin mRNA levels. A similar calpastatin mRNA diminution is observed upon drug-induced inhibition of protein translation. On the other hand, transforming growth factor beta (which inhibits differentiation) allows calpastatin synthesis and prevents the diminution in calpastatin mRNA. The overall results suggest that at the onset of myoblast differentiation, calpastatin is regulated mainly at the level of translation and that an inhibition of calpastatin synthesis leads to the decrease in its mRNA stability. The existing calpastatin then diminishes, resulting in decreased calpastatin activity in the fusing myoblasts, allowing calpain activation and protein degradation required for fusion.

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Epidermal growth factor (EGF) stimulates the growth of various types of cells via its cell surface tyrosine kinase receptor. The EGF receptor (EGF-R) has an oncogenic potential when overexpressed in a wide range of tumor cells. Geldanamycin (GA) and herbimycin (HA), specific inhibitors of the cytosolic chaperone HSP 90 and its endoplasmic reticulum homologue GRP 94, were shown to accelerate degradation of the EGF-R and of its homologue p185(c-)(erbB-2). Here we compared the effects of GA and HA on intracellular degradation and maturation of EGF-R. By using an inhibitor of proteasomal degradation, we learned that GA, but not HA, blocks processing of newly synthesized EGF-R. The effects of GA and HA on receptor degradation are mediated by the cytosolic portion of EGF-R and could be conferred to the erythropoietin receptor (EPO-R), by employing the respective chimera. Neither HA nor GA affected stability of newly synthesized EGF-R lacking the cytosolic domain (Ex EGF-R), but GA caused intracellular retention of this mutant. Taken together, our results imply that GA has two distinct targets of action on the EGF-R, one for promoting its degradation and another for mediating its intracellular retention. Apparently, degradation of the EGF-R mediated by GA or HA requires the presence of the EGF-R cytosolic domain, whereas intracellular retention in the presence of GA is coupled to the extracellular domain of the EGF-R.

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The erythropoietin receptor (EPO-R) is the cellular target for erythropoietin (EPO), the primary hormone that mediates the proliferation of immature erythroblasts and their differentiation into mature erythrocytes. Unusual features of the EPO-R are its short half-life (t(1/2) 1-2 h), its degradation via multiple pathways and the fact that less than 1% of total cellular EPO-R molecules are found on the cell surface. The contribution of EPO-R structural determinants to the regulation of its intracellular metabolism is still unclear. The epidermal growth factor receptor (EGF-R), unlike the EPO-R, is efficiently transported to the cell surface and displays a much longer metabolic half-life. To determine which EPO-R cytosolic domains are involved in intracellular degradation, we studied chimeric receptor molecules constructed of EGF-R extracellular and transmembrane parts, linked to the full length or truncated cytosolic part of the EPO-R. The chimeras were expressed in transiently transfected COS 7 cells and stably expressed in Ba/F3 cells. Our experiments indicate that the cytosolic part of the EPO-R contains determinants that mark it for rapid degradation, in association with the endoplasmic reticulum (ER). This degradation was insensitive to brefeldin A and was inhibited by specific proteasomal inhibitors. A truncated EGF-R/EPO-R chimera containing only 50 amino acids of the EPO-R membrane-proximal cytosolic part was also rapidly degraded suggesting that these 50 amino acids are involved in receptor degradation.

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Erythropoietin (EPO) promotes the viability, proliferation and differentiation of mammalian erythroid progenitor cells via its specific cell surface receptor. The EPO receptor (EPO-R) is a member of the cytokine receptor superfamily and is comprised of one identified subunit which homodimerizes upon ligand binding. To study the role of the intracellular domain of the EPO-R in the endocytosis of EPO, we compared the rate and extent of 125I-EPO endocytosis by wild type (wt) EPO-R and five cytoplasmically truncated EPO-Rs: 1-251 EPO-R, 1-257 EPO-R, 1-267 EPO-R, 1-276 EPO-R and 1-306 EPO-R which contain 4, 10, 20, 29 or 59 amino acids of the cytoplasmic domain, respectively. We also studied an EPO-R mutant (PB) which lacks amino acid residues 281-300 of the cytoplasmic domain. The experiments were conducted in COS 7 cells transfected with the EPO-R cDNAs and in Ba/F3 cells stably expressing the wt EPO-R, 1-251 or 1-257 EPO-R. Cells expressing wt EPO-R, PB EPO-R (delta281-300), 1-276 EPO-R or 1-306 EPO-R internalized approximately 50% of 125I-EPO bound to the cell surface, while cells expressing 1-251, 1-257 or 1-267 EPO-R internalized only 25% of the bound 125I-EPO. The steady-state expression levels of these latter receptors on the cell surface were typically 2-5-fold higher than wt EPO-R. Our data indicate that amino acid residues 267-276 (FEGLFTTHK) of the EPO-R cytoplasmic domain may have a role in receptor internalization. Metabolic labeling experiments suggest that in transiently transfected COS 7 cells most of the wt EPO-R and 1-257 EPO-Rs do not exit the ER and may be degraded there. The half-life of both receptors was essentially similar and was in the range of 1 h. In Ba/F3 cells the mature Golgi processed 1-257 EPO-R was more stable than the corresponding form of the wt EPO-R, possibly contributing to its higher cell surface expression.

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We report a patient who developed stiff-man syndrome, including disabling shoulder subluxation and wrist ankylosis, in association with breast cancer. Immunologic investigations disclosed autoimmunity directed against not only glutamic acid decarboxylase but also amphiphysin, a 128-kd protein located in the presynaptic compartment of neurons. The patient improved after surgery and corticosteroid treatment and has been stable for nearly 4 years on only anti-estrogenics. The triad of stiff-man syndrome, breast cancer, and autoantibodies against amphiphysin identifies a new autoimmune paraneoplastic syndrome of the CNS.

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BACKGROUND AND PURPOSE: We sought to determine whether early (< 8 hours) or delayed (8 to 24 hours) recanalization after stroke may be an independent variable in the improvement of clinical outcome in patients with occlusion of the middle cerebral artery. METHODS: We prospectively studied 77 patients by combined Scandinavian Stroke Scale score at admission, repeated computed tomography and angiography before and after thrombolytic treatment at < 8 hours after stroke onset, and transcranial Doppler ultrasound 24 hours later. We tested an association between clinical and neuroradiological baseline characteristics, recanalization, and outcome as assessed by the modified Rankin Scale 4 weeks after stroke and determined the effect of recanalization on mortality and good outcome (Rankin Scale grades 0 to 3) by multiple logistic regression analyses. RESULTS: Recanalization rates at 8 and 24 hours after stroke correlated with sites of occlusion (middle cerebral artery branch, 73% and 73%, trunk, 27% and 38%, respectively; intracranial internal carotid artery bifurcation, 14% and 14%; P = .002), collaterals (good, 43% and 51%, respectively; scarce, 17% and 19%, respectively; P = .01), and Scandinavian Stroke Scale score at admission (P = .002). Six of 6 patients with delayed recanalization had good outcomes. Recanalization at < 8 hours after symptom onset had no independent predictive value for good outcome (P = .69). Recanalization at 24 hours increased the proportion of good outcomes from 23% to 75% in a subgroup of patients. Recanalization did not independently affect mortality (P > .15). CONCLUSIONS: Even if delayed, arterial recanalization may improve clinical outcome in a subgroup of patients with middle cerebral artery occlusion.

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PURPOSE: To investigate the incidence and prognostic value of local brain swelling, the extent of parenchymal hypodensity, and the hyperdense middle cerebral artery sign as shown by CT within the first 5 hours after the onset of symptoms in patients with angiographically proved middle cerebral artery trunk occlusions. METHODS: Fifty-three patients were studied prospectively with CT 46 to 292 minutes (median, 120; mean, 134 +/- 59) after symptom onset and scored clinically at admission and 4 weeks later. All patients were treated with recombinant tissue plasminogen activator (30 to 100 mg). RESULTS: Early CT showed parenchymal hypodensity in 43 patients (81%), local brain swelling in 20 patients (38%), and hyperdensity of the middle cerebral artery trunk in 25 patients (47%). Hypodensity covering more than 50% of the middle cerebral artery territory had an 85%, local brain swelling a 70%, and the hyperdense middle cerebral artery sign a 32% positive predictive value for fatal clinical outcome. Specificity of these findings for fatal outcome was 94%, 83%, and 51%, respectively, and sensitivity was 61%, 78% and 44%, respectively. CONCLUSIONS: Early CT in acute middle cerebral artery trunk occlusion is highly predictive for fatal clinical outcome if there is extended hypodensity or local brain swelling despite aggressive therapeutic attempts such as thrombolysis or decompressive surgery.

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Investigated the effects of rational vs. irrational belief systems (as measured by the Ellis Irrational Values Scale) and rational vs. irrational self-verbalizations on levels of anxiety and persistence on a performance task. Ss (N = 40) were instructed to assemble a virtually insolvable task call Soma. The variables of interest were how long each S would persist on this task and how much anxiety (as measured by the A-State portion of the State-Trait Anxiety Inventory) was aroused in working on this task. Following a baseline trial trying to solve Soma, Ss were assigned to either a rational or irrational self-talk condition and were led to believe that such self-talk would help in a second attempt to solve Soma. In line with cognitive models of psychology, it was found that rational self-talk Ss showed a significant decrease in levels of state anxiety compared to irrational self-talk Ss in attempting to solve Soma in the second trial. Contrary to cognitive models of psychology, scores obtained from the EIVS and the A-Trait portion of the STAI were not found to be related to persistence.

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