We have used the mdx mice strain (C57BL/10ScSn-mdx) as an experimental subject for the study of reiterative skeletal muscle necrosis–regeneration with basement membrane preservation. In young mdx muscle, by means of Hematoxylin–Eosin staining, different types of degenerative–regenerative groups (DRG) can be recognized and assigned to a defined muscle regeneration phase. To evaluate the expression of known key-regulatory genes in muscle regeneration, we have applied Laser Capture Microdissection technique to obtain tissue from different DRGs encompassing the complete skeletal muscle regenerative process. The expression of MyoD, Myf-5 and Myogenin showed a rapid increase in the first two days post-necrosis, which were followed by MRF4 expression, when newly regenerating fibers started to appear (3–5 days post-necrosis). MHCd mRNA levels, undetectable in mature non-injured fibers, increased progressively from the first day post-necrosis and reached its maximum level of expression in DRGs showing basophilic regenerating fibers. TGFβ-1 mRNA expression showed a prompt and strong increase following fiber necrosis that persisted during the inflammatory phase, and progressively decreased when new regenerating fibers began to appear. In contrast, IGF-2 mRNA expression decreased during the first days post-necrosis but was followed by a progressive rise in its expression coinciding with the appearance of the newly formed myofibers, reaching the maximum expression levels in DRGs composed of medium caliber basophilic regenerating myofibers (5–7 days post-necrosis). mdx degenerative–regenerative group typing, in conjunction with laser microdissection-based gene expression analysis, opens up a new approach to the molecular study of skeletal muscle regeneration.

We have used the mdx mice strain (C57BL/10ScSn-mdx) as an experimental subject for the study of reiterative skeletal muscle necrosis–regeneration with basement membrane preservation. In young mdx muscle, by means of Hematoxylin–Eosin staining, different types of degenerative–regenerative groups (DRG) can be recognized and assigned to a defined muscle regeneration phase. To evaluate the expression of known key-regulatory genes in muscle regeneration, we have applied Laser Capture Microdissection technique to obtain tissue from different DRGs encompassing the complete skeletal muscle regenerative process. The expression of MyoD, Myf-5 and Myogenin showed a rapid increase in the first two days post-necrosis, which were followed by MRF4 expression, when newly regenerating fibers started to appear (3–5 days post-necrosis). MHCd mRNA levels, undetectable in mature non-injured fibers, increased progressively from the first day post-necrosis and reached its maximum level of expression in DRGs showing basophilic regenerating fibers. TGFβ-1 mRNA expression showed a prompt and strong increase following fiber necrosis that persisted during the inflammatory phase, and progressively decreased when new regenerating fibers began to appear. In contrast, IGF-2 mRNA expression decreased during the first days post-necrosis but was followed by a progressive rise in its expression coinciding with the appearance of the newly formed myofibers, reaching the maximum expression levels in DRGs composed of medium caliber basophilic regenerating myofibers (5–7 days post-necrosis). mdx degenerative–regenerative group typing, in conjunction with laser microdissection-based gene expression analysis, opens up a new approach to the molecular study of skeletal muscle regeneration.

A. Vihola, M. Sirito, L. L. Bachinski, O. Raheem, M. Screen, T. Suominen, R. Krahe and B. Udd (2013) Neuropathology and Applied Neurobiology39, 390–405

Magnetic properties of fine Sr 2FeMoO 6 (SFMO) powders were systematically studied and superparamagnetism was observed. The SFMO samples were prepared using a citrate-gel method and were characterized by X-ray diffraction (XRD), ferromagnetic resonance (FMR) and Mossbauer spectroscopy. The XRD measurements showed that the powders are nearly pure and the Rietveld refinement gave particle sizes of 31 and 197nm and antisite disorders of 10 and 15%, respectively. The 197nm crystallite size sample has a T C=415 K and a magnetic moment of 3.0 mu B/f.u. Several measurements made by SQUID magnetometer, FMR and Mossbauer spectroscopy showed that the 31nm crystallite sample behaves superparamagnetically with blocking temperature T B=35 K and it has a reduced saturation magnetization of 1.0 mu B/f.u. at 5K and effective paramagnetic moment of 3.0 mu B. [All rights reserved Elsevier]

Based on previous reports the frequency of co-segregating recessive chloride channel (CLCN1) mutations in families with myotonic dystrophy type 2 (DM2) was suspected to be increased. We have studied the frequency of CLCN1 mutations in two separate patient and control cohorts from Germany and Finland, and for comparison in a German myotonic dystrophy type 1 (DM1) patient cohort. The frequency of heterozygous recessive chloride channel (CLCN1) mutations is disproportionally higher (5%) in currently diagnosed DM2 patients compared to 1.6%in the control population (p = 0.037), while the frequency in DM1 patients was the same as in the controls. Because the two genes segregate independently, the prevalence of CLCN1 mutations in the total DM2 patient population is, by definition, the same as in the control population. Our findings are, however, not based on the total DM2 population but on the currently diagnosed DM2 patients and indicate a selection bias in molecular diagnostic referrals. DM2 patients with co-segregating CLCN1 mutation have an increased likelihood to be referred for molecular diagnostic testing compared to DM2 patients without co-segregating CLCN1 mutation.

Sr 2FeMoO 6 (SFMO) thin films were grown on SrTiO 3 and MgO single crystal substrates by pulsed laser deposition. The SFMO target with nanometer sized grains for the film preparation was made from powder prepared by citrate-gel method. The parameters for ablation were optimized and the importance of the substrate temperature is observed. Film quality was verified with various X-ray diffraction methods and magnetometric measurements. The films are pure, without impurities such as metallic iron, Fe 2O 3, SrMoO 3 or SrMoO 4 and they are completely c-axis oriented. The Curie temperature for the films is higher than room temperature. [All rights reserved Elsevier].