In primary myelofibrosis (PMF) and essential thrombocythemia (ET) the megakaryocytic lineage characteristically shows aberrant proliferation and maturation in which the regulatory microRNA (miR) system might be involved. Laser-microdissected PMF and ET megakaryocytes were analysed with real-time polymerase chain reaction (PCR) low density arrays comprising 365 microRNAs. The highest megakaryocytic expression levels were observed for miR-223, which is known to be expressed also in granulopoiesis. Cluster analysis revealed a tendency of disease-specific megakaryocytic microRNA expression profiles indicating that a complex shift of microRNA expression appears to be the underlying defect. Increased accumulation of miR-146b was observed in cellular stage PMF (p = 0.0125) but not ET megakaryopoiesis. In conclusion, this is the first microRNA profiling of in situ-derived PMF, ET and normal megakaryocytes.

International audienceMicro RNA (miRNA) are small non-coding RNA molecules which have a post-transcriptional inhibitory regulation function, e.g. in megakaryopoiesis. A characteristic of Philadelphia chromosome-negative myeloproliferative neoplasm (Ph MPN) is the abundance of morphologically aberrant megakaryocytes. Based on previously published in vitro megakaryocytic differentiation assay data, we selected miRNA 10a, 17-5p, 20a and 126 and potential target proteins (HOXA1, RUNX1) for analysis of laser-microdissected bone marrow megakaryocytes from Ph MPN and controls ( = 66). Furthermore, we tested a potential influence of cytoreductive treatment on miRNA expression in bone marrow cells during the course of Ph MPN ( = 18). In summary, miRNA 17-5p, 20a and 126 are constitutively expressed in Ph MPN megakaryopoiesis while low or absent miRNA 10a appeared to correlate with strong megakaryocytic HOXA1 protein expression. No association to thrombocytosis, JAK2 mutations or cytoreductive treatment (bone marrow cells) were observed

through a drilled bone hole from dorsal to ventral and then sutured on itself. The follow-up of the radiological and clinical results showed in 30 cases an excellent, in 6 cases a satisfactory result.Zusammenfassung. [1972][1973][1974][1975][1976][1977][1978] wurden an der Medizinischen Hochschule Hannover 43 fibulare Bandplastiken durchgeffihrt; 36 nachuntersucht. In 22 F~illen wurde eine modifizierte Evans-Plastik angewandt: Die distal gestielte Peronaeus brevis-Sehne wird halb gespalten bis auf H6he des prox. Retinaculums, dort nach ventral durch den AuBenkn6chel gefiihrt und u. h. davon in sich vern/iht. Radiologisch wurden pr~i-und postoperativ gehaltene standardisierte Aufnahmen vom OSG in 2 Ebenen angefertigt. Nach 20 klinischen und 3 radiologischen Parametern waren 30 Plastiken sehr gut bis gut, 6 befriedigend.Summary. From 1972 to 1979, 728 patients with dislocated ankle fractures were treated by osteosynthesis at the "Bergmannsheil"Bochum. 684 patients were followed up to the time when the metal implants were removed (~ 6.8 months post op.) : The functional result was good in 534 (78 %), sufficient in 103 (15 %), and insufficient in 47 (7 %) cases. 306 patients were followed up 3 to 8 years post op. : The functional result was good in 235 (77 %), sufficient in 52 (17 %), and insufficient in 19 (6 %) cases.