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The article discusses the works of novelist Anthony Trollope and provides information on the novels' critical reception on the German market throughout the 19th century. Topics include the German publishing of Trollope's works in English language, the translation of his works by August Kretzschmar and Lina Kayser, and the popularity and holdings of Trollope's novels in lending libraries. Novels include "The Three Clerks," "The Macdermots of Ballycloran," and "Framley Parsonage."

The article discusses the palaeographer C. Maier's practices when he examined the medieval manuscript the "Vercelli Book" especially his use of a reagent which damaged certain portions of the manuscript. Topics include the need for examining the stains left behind by C. Maier in the manuscript to understand material integrity of manuscripts, and information on various reagents that are used by paleographers.

Abstract: The effect of ibandronate 150mg/once monthly in the treatment of post-menopausal osteopenia and osteoporosis on bone micro-structure at the distal tibia and radius has not been considered to date. Seventy post-menopausal women with osteoporosis or osteopenia were recruited. All subjects received calcium and vitamin D supplementation and were randomized to either a group which took 150mg ibandronate oral monthly or a placebo group over a 12-month period. μCT measures of the distal tibia and radius were conducted every three months, with DXA lumbar spine and hip measurements conducted only pre and post and serum markers of bone formation and resorption measured every 6months. After 12-months no significant impact of ibandronate on the primary outcome measures bone-volume to tissue-volume and trabecular separation at the distal tibia (p ≥0.15) was found. Further multiple regression analyses of the primary end-points indicated a significant effect favoring the ibandronate intervention (p =0.045). Analysis of secondary end-points showed greater increases in distal tibia cortical thickness, cortical density and total density (p ≤0.043) with ibandronate and no significant effects at the distal radius, but greater increases of hip DXA-BMD and lumbar spine DXA-BMD (p ≤0.017). Ibandronate use resulted in a marked reduction in bone turnover (p <0.001). While ibandronate resulted in greater mineralization of bone, this effect differed from one body region to another. There was some impact of ibandronate on bone structure (cortical thickness) at the distal tibia, but not on bone-volume to tissue-volume or trabecular separation. [Copyright &y& Elsevier]

Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by remodelling of the bone marrow, including progressive myelofibrosis and exaggerated angiogenesis. Advanced PMF frequently shows a full-blown fibre meshwork, which avoids aspiration of cells, and the expression profile of genes related to stroma pathology at this stage remains largely undetermined. We investigated bone marrow core biopsies in PMF showing various degrees of myelofibrosis by custom-made low density arrays (LDA) representing target genes with designated roles in synthesis of extracellular matrix, matrix remodelling, cellular adhesion and motility. Among a set of 11 genes up-regulated in advanced stages of PMF ( P ≤ 0·01) three candidates, PTK2 protein tyrosine kinase 2 ( PTK2), transforming growth factor β type II receptor ( TGFBR2) and motility-related protein-1 (CD9 molecule, CD9), were investigated in more detail. PTK2, TGFBR2 and CD9 were significantly overexpressed in larger series of advanced PMF stages ( P ≤ 0·01 respectively). Endothelial cells of the increased microvessel network in PMF could be identified as a predominant source for PTK2, TGFBR2 and CD9. CD9 also strongly identified activated fibroblasts in advanced myelofibrosis. We conclude that PTK2, TGFBR2 and CD9 represent new target molecules involved in bone marrow remodelling of PMF and warrant further investigation for potential targeted therapy. [ABSTRACT FROM AUTHOR]

Abstract: The suppressor of cytokine signalling-1 (SOCS-1) is a negative regulator of signal transduction mediated by cytoplasmic tyrosine kinases such as the Janus kinases (JAKs). We investigated SOCS-1 expression in bone marrow cells from Philadelphia chromosome negative chronic myeloproliferative disorders (Ph− CMPD) and normal haematopoiesis (n =121), and additionally in peripheral blood samples (n =18). Except for chronic idiopathic myelofibrosis harbouring wild-type JAK2, other Ph− CMPD expressed significantly higher SOCS-1 levels of up to 14-fold compared to the control group (p <0.001) independent of the JAK2 status. The mononuclear cell fraction but not granulocytes in patients with Polycythaemia vera also significantly overexpressed SOCS-1. We conclude that up-regulation of the SOCS-1 gene might reflect a compensatory feedback mechanism with different emphasis among Ph− CMPD subtypes independent of an underlying JAK2 (V617F) mutation. [Copyright &y& Elsevier]

Objectives: Friend leukemia integration-1 (Fli-1), a member of the Ets gene family of transcription factors, has been demonstrated to be a target of a leukaemia inducing virus in mice, and is known to be part of a fusion gene in Ewings’ sarcoma in humans. Wild-type Fli-1 is involved in lineage commitment of megakaryocytes and myeloid progenitors through induction of Janus kinases (JAKs) following ligand binding to cytokine and growth factor receptors. Proliferation of atypical megakaryocytes is a predominant histopathological feature in Philadelphia chromosome negative chronic myeloproliferative disorders (Ph− CMPD) and a potential aberrant expression of Fli-1 has not been investigated so far. Methods: Fli-1 expression was investigated by real-time RT-PCR and immunohistochemistry in bone marrow cells derived from Ph− CMPD ( n = 80) and non-neoplastic haematopoiesis ( n = 21) following determination of the JAK2 status. Results: Fli-1 mRNA expression was significantly higher in Essential thrombocythaemia (ET) with JAK2 (V617F) compared with other Ph− CMPD and control ( P < 0.001). By immunohistochemistry, Fli-1 protein could be detected in nuclei of atypical megakaryocytes in Ph− CMPD and, less accentuated, in non-neoplastic megakaryocytes. Fli-1 protein expression by myeloid progenitors was considerably heterogenous in Ph− CMPD independent of an underlying JAK2 (V617F) mutation and without notable differences to non-neoplastic haematopoiesis. Conclusion: Fli-1 is rather constitutively expressed by bone marrow cells in Ph− CMPD independent of the underlying JAK2 status. The overall stronger labelling for Fli-1 in megakaryocytes in Ph− CMPD most likely reflects the degree of polyploidisation but aberrant activation of nuclear target genes can not be excluded. [ABSTRACT FROM AUTHOR]

Background: Microinjection of foreign DNA into pronuclei of zygotes has been the method of choice for the production of transgenic domestic animals. Following microinjection the transgene is randomly integrated into the host genome which can be associated with insertional mutagenesis and unwanted pathological side effects. Methods: Here, we evaluated the health status of pigs transgenic for the human regulator of complement activation (RCA) CD59 and conducted a complete pathomorphological examination on 19 RCA transgenic pigs at 1 to 32 months of age from nine transgenic lines. Nine wild-type animals served as controls. Expression levels of human complement regulator CD59 (hCD59) mRNA were measured by RT-PCR and distribution of hCD59 protein was determined by immunohistochemistry. Results: Albeit variable transgene expression levels, no specific pathomorphologic phenotype associated with the presence of the transgene in all analyzed pig lines could be detected. Conclusions: Transgenic expression of this human RCA gene construct is not correlated with a specific pathological phenotype in pigs. This is crucial for the application of the technology and the use of transgenic pigs for biomedical and agricultural applications. [ABSTRACT FROM AUTHOR]

Keloid and hypertrophic scarring represent chronic disfiguring dermatoses with a high resistance to therapy. The aim of our study was to assess for the first time the quality of life of patients with hypertrophic scars and keloids, because they suffer from quality of life impairment as much as patients with other chronic skin diseases. An item-pool was created modifying and supplementing the items of the Questionnaire on Experience with Skin Complaints. This questionnaire was distributed to 100 outpatients with keloids and hypertrophic scars. A factor analysis was used to identify the underlying dimensions. Two scales (psychological and physical impairment) of the questionnaire with nine and five items, respectively, were established. Test–retest reliability of the questionnaire was excellent (corr>0.9). Good validity was suggested by the correlation of physical impairment with pain ( P≤0.001), pruritus ( P<0.001), and the amount of restriction of mobility ( P<0.001). The psychological scale was associated with pain and restriction of mobility, although the correlations were lower. This study demonstrates for the first time an impairment of quality of life in a large group of patients with keloid and hypertrophic scarring. [ABSTRACT FROM AUTHOR]

Allograft-specific T-cell activation requires two signals, ‘signal one’ via the T-cell receptor and ‘signal two’ via costimulatory pathways. Animal models provide promising data that blockade of costimulatory signals can lead to T-cell anergy and tolerance. We analyzed 72 formalin-fixed and paraffin-embedded sequential heart allograft biopsies from 22 patients by quantitative real-time reverse transcriptase-polymerase chain reaction for the mRNA expression of the costimulatory molecules CD28, CD80, CD86, CD40, and CD154. mRNA expression levels were correlated to histological grade and time-point of rejection. mRNA expression of costimulatory molecules predominantly expressed by antigen-presenting cells (CD80, CD86, CD40), correlated with histological grade of cell-mediated acute rejection. Costimulatory molecules were up-regulated not only during rejection episodes early after transplantation, but also at late occurring rejection. The present results suggest a simultaneous and long-term therapeutical blockade of more than one costimulatory pathway for the prevention of repetitive T-cell mediated acute rejection episodes after heart transplantation. [ABSTRACT FROM AUTHOR]

Advanced chronic idiopathic myelofibrosis (IMF) with osteosclerosis and increase and thickening of bone trabeculae is typically contrasted by the absence or sparse presence of osteoclasts. Because osteoclast formation can be inhibited by osteoprotegerin ( OPG) we investigated OPG expression in IMF with severe fibrosis and osteosclerosis, which expressed significantly higher (up to 71-fold) OPG mRNA levels when compared with prefibrotic cellular IMF and control cases. The receptor activator of nuclear factor kappaB ligand ( RANKL), a positive regulator of osteoclast differentiation and putative antagonist of OPG was overexpressed by up to 34-fold exclusively in advanced IMF. Case-specific calculation of the RANKL/OPG ratio in advanced IMF showed a wide range without significant differences when compared with the prefibrotic IMF and non-neoplastic haematopoiesis. Immunohistochemical detection of OPG protein revealed strong labelling of endothelial cells within proliferating vessels in fibrotic IMF and heterogeneously labelled megakaryocytes, and fibroblasts. Osteosclerosis and impaired osteoclast function in IMF appears to be associated with upregulated endothelial OPG expression but concomitant reduction of the antagonist RANKL could not be demonstrated. We conclude that osteosclerosis in IMF is associated with increased endothelial OPG expression without concomitant RANKL downregulation. [ABSTRACT FROM AUTHOR]

Keloids are benign skin tumours occurring during wound healing in genetically predisposed patients. They are characterized by an abnormal deposition of extracellular matrix components, particularly collagen. There is uncertain evidence that transforming growth factor-beta (TGF β) is involved in keloid formation. Therefore we investigated the expression of TGFβ1, 2 and 3 and their receptors in keloids. hypertrophic scars and normal skin. Dermal fibroblasts were obtained from punch biopsies of patients with keloids and hypertrophic scars and from normal skin of healthy individuals. Total RNA was isolated and the expression of TGF β1, 2 and 3 and of TGF β receptors I and II (TGFβRI and II) was analysed by real-time PCR using the Lightcycler technique. Our data demonstrate significantly lower TGFβ2 mRNA with fibroblasts derived from keloids and normal skin (pO.O5). In contrast, TGFβ3 mRNA expression was significantly tower in keloid fibroblasts in comparison with fibroblasts derived from hypertrophic sear and normal skin (p<0.01). TGFβRII mRNA expression was significantly decreased in hypertrophic scar fibroblasts (p<0.001) and TGFβRII mRNA expression was decreased in keloids compared with hypertrophie sear fibroblasts (p<0.001). The ratio of TGF βRI/TGF βRII expression was increased in keloids compared with hypertrophic scar and normal skin fibroblasts. As recently supposed, an increased TGFβRI/TGFβRII ratio could promote fibrosis. Therefore our data support a possible role of TGFβRI and TGFβRII in combination with a certain TGFβ expression pattern as fibrosis-inducing factors in keloids. [ABSTRACT FROM AUTHOR]

Philadelphia chromosome negative chronic myeloproliferative disorders (Ph- CMPD) comprise haematopoietic stem cell disorders with currently unknown underlying molecular defect.Insulin-like growth factor 2 (IGF-2) is an imprinted gene that is known to be involved in the regulation of normal cell growth and that is overexpressed by a variety of tumors. The expression of IGF-2 in bone marrow cells is largely unknown.In order to elucidate gene expression level, protein expression pattern, and a potential role of IGF-2 in the pathogenesis of Ph- CMPD, we quantitatively analyzed the expression of the IGF-2 gene in bone marrow cells of 69 cases with Ph- CMPD and 31 control cases by applying real-time RT-PCR. IGF-2 gene expression in idiopathic myelofibrosis (IMF) was significantly increased by up to 11-fold as compared to the control group (P<0.0001). IMF also expressed higher IGF-2 gene level as compared to essential thrombocythaemia (ET) and polycythaemia vera (PV) (P<0.0001, P=0.005, respectively). Paranuclear IGF-2 protein could be demonstrated in IMF, ET, and PV exclusively in megakaryocytes and myeloid progenitor cells in contrast to undetectable IGF-2 protein in control cases. We conclude that overexpression of the IGF-2 gene is a pathogenic feature in IMF. In addition, an abundant translational and post-translational processing could explain the accumulation of IGF-2 protein detectable in all Ph- CMPD entities in contrast to non-neoplastic haematopoiesis.We conclude that IGF-2 represents a new molecular target for evaluation of underlying fundamental pathomechanisms in Ph- CMPD. [Copyright &y& Elsevier]

Telomerase is the enzyme required for the addition of telomeric repeats to the ends of chromosomes and thus for chromosome stability. Most somatic human cells lack telomerase activity because they do not express the telomerase reverse transcriptase (hTERT) gene. In contrast, in almost every neoplasia, cancer cells express hTERT and therefore prevent progressive telomere shortening during each cell division. Consecutively, cancer cells obtain the ability to divide without limits and overcome replicative senescence. Gene expression level of the telomerase catalytic subunit hTERT in normal and neoplastic haematopoiesis has not yet been described. Using a quantitative real-time RT-PCR assay, we analysed the level of hTERT expression in various haematologic stem cell disorders and normal bone marrow. We could demonstrate that hTERT is differentially expressed in various haematologic stem cell disorders with significant higher levels in refractory anemia (RA) and chronic myeloid leukemia (CML) compared to other haematopoietic stem cell disorders and non-neoplastic haematopoiesis which may be used as a prognostic indicator in these entities. [Copyright &y& Elsevier]

Bock O, Neusch M, Büsche G, Mengel M, Kreipe H. Constitutive expression of the FK506 binding protein 51 (FKBP51) in bone marrow cells and megakaryocytes derived from idiopathic myelofibrosis and non-neoplastic haematopoiesis. Eur J Haematol 2004: 72: 239–244. © Blackwell Munksgaard 2004. Overexpression of FK506 binding protein 51 (FKBP51) in megakaryocytic progenitor cells generated from purified CD34+ cells in patients with idiopathic myelofibrosis (IMF) has been demonstrated. It has been suggested that FKBP51 is involved in the dysregulation of the apoptotic programme with consecutive prolongation of cell survival. The knowledge of FKBP51 and its expression in bone marrow cells and mature megakaryocytes in non-neoplastic haematopoiesis and IMF is sparse. To evaluate a potential overexpression of FKBP51 in patients with IMF ( n = 37) compared with non-neoplastic haematopoiesis ( n = 31), total bone marrow cells as well as single megakaryocytes, isolated by laser microdissection, were quantitatively analysed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). By applying immunohistochemistry, FKBP51 gene expression was correlated with staining pattern and cellular localisation of the corresponding FKBP51 protein. We demonstrated that FKBP51 is constitutively expressed in non-neoplastic haematopoiesis. FKBP51 gene expression by total bone marrow cells as well as megakaryocytes was not significantly different in IMF. FKBP51 protein expression could be localised to myeloid progenitor cells as well as megakaryocytes. In particular, megakaryocytes were stained almost exclusively nuclear for FKBP51. No differences in expression patterns between both IMF and control cases could be demonstrated. For the first time, FKBP51 expression, in particular gene expression and subcellular localization was described in bone marrow cells of non-neoplastic and neoplastic haematopoiesis grown in vivo. We conclude that FKBP51 could be temporarily overexpressed in megakaryocytic progenitors rather than contribute to the accumulation of mature megakaryocytes in IMF. [ABSTRACT FROM AUTHOR]

Examines the relationships among the derivative structures of the perovskite type using group-subgroup relations between space groups. Tilted coordination octahedra characteristic of perovskites; Distortions of the octahedra; Space-group symmetry reductions.

Little is known about the expression of the polycythaemia rubra vera-1 ( PRV-1) gene in bone marrow cells. To determine the expression level of PRV-1 in the bone marrow, we analysed PRV-1 quantitatively in Polycythaemia vera, other chronic myeloproliferative disorders, and reactive states. We demonstrated that PRV-1 was constitutively expressed in both myeloproliferative and reactive states. We concluded that, rather than an upregulation of the PRV-1 gene in the clonal haematopoiesis of polycythaemia vera, a failure to downregulate PRV-1 in granulocytes emigrating from the bone marrow might be responsible for the increase of transcripts in peripheral cells. [ABSTRACT FROM AUTHOR]

Leukemia (2003) 17, 815-816. doi:10.1038/sj.leu.2402830 [ABSTRACT FROM AUTHOR]

Objective: Among Philadelphia chromosome−negative myeloproliferative neoplasms (Ph− MPN), essential thrombocythemia (ET) and the prefibrotic phase of primary myelofibrosis (PMF) represent two subtypes with considerable overlap. Materials and Methods: In this study, histopathological classification of 490 MPN cases was correlated with the allelic burden of JAK2V617F and MPLW515L. Results: Ph− MPN entities largely overlap with regard to JAK2V617F and MPLW515L allele burden, but ET displayed mutant allele burden <50%. PMF with different stages of myelofibrosis all yielded similar JAK2V617F allele burden. At initial presentation one-quarter of prefibrotic PMF cases exhibited an allele burden exceeding 50% (38% median JAK2V617F alleles, n=102). In ET, its main differential diagnosis, not a single case was found with >40% JAK2V617F alleles (median, 24% JAK2V617F alleles; n=90; p <0.001). Increase in JAK2V617F alleles during follow-up could not be linked to fibrosis or blastic progression but was related to polycythemic transformation in ET. MPLW515L was found in 3% of ET and 8% of PMF, with a significantly higher percentage of mutated alleles in fibrotic than prefibrotic PMF (median, 78% MPLW515L alleles; p <0.05). Conclusion: Histopathological categories ET and prefibrotic PMF correlate with significant differences in mutant allelic burden of JAK2V617F, but not of MPLW515L which, by contrast to JAK2V617F, shows a higher percentage of mutated alleles in fibrotic than in prefibrotic cases. Thus, for Ph− MPN in which ET and prefibrotic PMF represent the most probable diagnoses, a JAK2V617F allele burden >50% favors a diagnosis of prefibrotic PMF. [Copyright &y& Elsevier]

Summary: Between 1998 and 2018, the number of hospitalizations for major osteoporotic fractures increased. After standardization for age, these numerical increases translated into a reduced incidence of hospitalizations for hip fractures and an increased incidence of hospitalizations for spine, proximal humerus, and distal radius fractures in both sexes. Introduction: The longterm epidemiological trends of hospitalizations for major osteoporotic fractures (MOF) between 1998 and 2018 in Switzerland are unknown. Methods: The absolute number of acute hospitalizations for MOF (hip fractures and fractures of the spine, proximal humerus, and distal radius) and related length of acute hospital stay were extracted from the medical database of the Swiss Federal Office of Statistics. Age-standardized incidence rates were calculated using 1998 as the reference year. Results: Hospitalizations for MOF increased from 4483 to 7542 (+ 68.2%) in men and from 13,242 to 19,362 (+ 46.2%) in women. The age-standardized incidence of hospitalizations for MOF increased by 5.7% in men (p = 0.002) and by 5.1% in women (p = 0.018). The age-standardized incidence of hip fractures decreased by 15.3% in men (p < 0.001) and by 21.5% in women (p < 0.001). In parallel, the age-standardized incidence of MOF other than hip fractures increased by 31.8% in men (p < 0.001) and by 40.1% in women (p < 0.001). The mean length of acute hospital stays for MOF decreased from 16.3 to 8.5 days in men and from 16.9 to 8.1 days in women. Conclusion: Between 1998 and 2018, the number of hospitalizations for MOF increased significantly by a larger extent than expected based on the ageing of the Swiss population alone. This increase was solely driven by an increased incidence of MOF other than hip fractures as incident hip fractures decreased over time in both sexes, more so in women than in men. [ABSTRACT FROM AUTHOR]

Summary: Evolution of erythrocyte transfusion‐dependent (RBC‐TD) anaemia associated with haploinsufficiency of the ribosomal protein subunit S14 gene (RPS14) is a characteristic complication of myelodysplastic syndromes (MDS) with del(5q) [MDS.del(5q)]. Evaluating 39 patients with MDS.del(5q), <5% of anaemia progression was attributable to RPS14‐dependent alterations of normoblasts, pro‐erythroblasts, or CD34+CD71+ precursors. Ninety‐three percent of anaemia progression and 70% of the absolute decline in peripheral blood Hb value were attributable to disappearance of erythroblastic islands (Ery‐Is). Ery‐Is loss occurred independently of blast excess, TP53 mutation, additional chromosome aberrations and RPS14‐dependent alterations of normoblasts and pro‐erythroblasts. It was associated with RPS14‐dependent intrinsic (S100A8+) and extrinsic [tumour necrosis factor α (TNF‐α)‐overproduction] alterations of (CD169+) marrow macrophages (p < 0.00005). In a mouse model of RPS14 haploinsufficiency, Ery‐Is disappeared to a similar degree: approximately 70% of Ery‐Is loss was related to RPS14‐dependent S100A8 overexpression of marrow macrophages, less than 20% to that of CD71highTer119− immature precursors, and less than 5% to S100A8/p53 overexpression of normoblasts or pro‐erythroblasts. Marked Ery‐Is loss predicted reduced efficacy (erythrocyte transfusion independence) of lenalidomide therapy (p = 0.0006). Thus, erythroid hypoplasia, a characteristic complication of MDS.del(5q), seems to result primarily from a macrophage‐associated failure of the erythropoietic niche markedly reducing the productive capacity of erythropoiesis as the leading factor in anaemia progression and evolution of RBC‐TD in MDS.del(5q). [ABSTRACT FROM AUTHOR]

Lake Victoria is famous for its in evolutionary terms young but species-rich assemblage of cichlid fishes. This 'superflock' also includes additional species from adjacent water systems. Lake Victoria is surrounded by several smaller lakes that are connected to the main water body of Lake Victoria only through swampy areas. Lake Kanyaboli is one such lake, harbouring a much poorer species diversity, mostly comprised of Lake Victoria endemics, some of which are now considered extirpated from the main lake. The focus of this study was on the modern haplochromine component of the cichlid fauna, represented by Lipochromis maxillaris, Astatotilapia nubila, Xystichromis phytophagus and Astatotilapia sp. ' Bigeye', as well as a number of morphologically distinct haplochromine specimens that could not be assigned to any of the recognized species. We used five microsatellite markers to distinguish these five taxa. Genetically, L. maxillaris was clearly differentiated from all other taxa, and A. sp. ' Bigeye' was moderately differentiated from the remaining three. Astatotilapia nubila, X. phytophagus and the unidentified specimens constituted a partially overlapping cluster. As each of the clusters had several (5-14) private alleles, extremely recent divergence is suggested. As all taxa except for A. sp . ' Bigeye' and the unidentified specimens also occur or at least occurred in Lake Victoria, it is likely that they evolved as part of the Lake Victoria superflock, while A. sp . ' Bigeye' and the unidentified specimens may have currently evolved in situ. The observation of slightly distinct albeit overlapping body shapes and the extremely close genetic relationship between three of the five taxa are fully compatible and in support of the hybrid swarm theory of adaptive radiation. [ABSTRACT FROM AUTHOR]

A subset of myeloproliferative disorders (MPN) and myelodyplastic syndromes (MDS) evolves to fibrosis of the bone marrow associated with haematopoietic insufficiency. We have been interested in chemokines involved in fibrogenesis within the bone marrow. Besides TGFβ we could identify a number of additional mediators including osteoprotegerin and bone morphogenic proteins. In MPN JAK2 or MPL mutation are not linked to the propensity for bone marrow fibrosis. The hypothesis that an increased intramedullary decay of megakaryocytes undergoing appotosis takes place within the marrow, thus liberating fibrogenic cytokines, could not be confirmed. On the contrary, megakaryocytes in primary fibrosis revealed low expression of proapoptotic genes such as BNIP3. Interestingly, BNIP 3 expression was down regulated in megakaryocytic cell lines kept in hypoxic conditions. Furthermore, expression arrays revealed hypoxia inducible genes to be up-regulated in primary myelofibrosis. Fibrotic MPN are characterized by aberrant proplatelet formation which represent cytoplasmic pseudopodia and normally extend into the sinus. In fibrotic MPN orientation of proplatelet growth appears to be disturbed, which could lead to an aberrant deposition of platelets in the marrow with consecutive liberation of fibrogenic cytokines. [ABSTRACT FROM AUTHOR]

Abstract: Proplatelets represent pseudopodia of megakaryocytes which extend into bone marrow sinuses to release platelets. Proplatelets were visualized by immunohistochemical and confocal microscopy. In trephines from essential thrombocythaemia (ET, n =10), fibrotic (n =10) and pre-fibrotic (n =10) primary myelofibrosis (PMF) there was a significant increase of proplatelet density compared with normal bone marrow samples (n =10; p <0.001). Manifest fibrosis exhibited the highest density and volume ratio with significant differences to non-fibrotic PMF (p <0.001) and ET (p <0.001). This study demonstrates that besides megakaryocytic proliferation extensive pseudopodial proplatelet formation provides a hallmark of MPN. Fibrosing differ from non-fibrosing MPN by density and size of aberrant proplatelets. [ABSTRACT FROM AUTHOR]

Background We evaluated which aspects of neuromuscular performance are associated with bone mass, density, strength and geometry. Methods 417 women aged 60–94 years were examined. Countermovement jump, sit-to-stand test, grip strength, forearm and calf muscle cross-sectional area, areal bone mineral content and density (aBMC and aBMD) at the hip and lumbar spine via dual X-ray absorptiometry, and measures of volumetric vBMC and vBMD, bone geometry and section modulus at 4% and 66% of radius length and 4%, 38% and 66% of tibia length via peripheral quantitative computed tomography were performed. The first principal component of the neuromuscular variables was calculated to generate a summary neuromuscular variable. Percentage of total variance in bone parameters explained by the neuromuscular parameters was calculated. Step-wise regression was also performed. Results At all pQCT bone sites (radius, ulna, tibia, fibula), a greater percentage of total variance in measures of bone mass, cortical geometry and/or bone strength was explained by peak neuromuscular performance than for vBMD. Sit-to-stand performance did not relate strongly to bone parameters. No obvious differential in the explanatory power of neuromuscular performance was seen for DXA aBMC versus aBMD. In step-wise regression, bone mass, cortical morphology, and/or strength remained significant in relation to the first principal component of the neuromuscular variables. In no case was vBMD positively related to neuromuscular performance in the final step-wise regression models. Conclusion Peak neuromuscular performance has a stronger relationship with leg and forearm bone mass and cortical geometry as well as proximal forearm section modulus than with vBMD. [ABSTRACT FROM AUTHOR]

The microRNA/miR deregulation in BCR-ABL-negative myelodysplastic-myeloproliferative neoplasms (MDS/MPN) is not known. Myelopoiesis-associated miR-10a, miR-17-5p, miR-155, miR-223 and miR-424 were analysed by real-time polymerase chain reaction (PCR) in bone marrow cells of atypical chronic myeloid leukaemia (aCML, n = 7) and chronic myelomonocytic leukaemia (CMML, n = 8) and were compared to BCR-ABL-positive chronic myelogenous leukaemia (CML, n = 10) and non-neoplastic haematopoiesis ( n = 10). Down-regulation of miR-10a was found in CMML but also in CML (each p < 0.05, versus controls). Overexpression of miR-424 was detected in aCML ( p < 0.05, versus CML and controls). Despite different compositions of bone marrow cells, expression of myelopoiesis-associated microRNA shows mainly similar patterns in aCML and its main differential diagnosis CMML and does not allow discrimination of these two MDS/MPN entities. Therefore, the link of deregulated microRNA expression to disease-related phenotype and the underlying molecular mechanism are still unknown. [ABSTRACT FROM AUTHOR]

After publication of our article 1, we realized the need for posting a correction note in order to prevent i) overinterpretation of some results by the readers and ii) concerns about potentially unintended misguidance by the authors. [ABSTRACT FROM AUTHOR]

Primary myelofibrosis (PMF) is a chronic myeloproliferative neoplasm showing aberrant bone marrow remodeling with increased angiogenesis, progressive matrix accumulation, and fibrosis development. Thrombospondins (TSP) are factors sharing pro-fibrotic and anti-angiogenic properties, and have not been addressed in PMF before. We investigated the expression of TSP-1 and TSP-2 in PMF related to the stage of myelofibrosis ( n = 51) and in individual follow-up biopsies by real-time PCR, immunohistochemistry, and confocal laser scanning microscopy (CLSM). TSP-1 was significantly overexpressed (p < 0.05) in all stages of PMF when compared to controls. Individual follow-up biopsies showed involvement of TSP-1 during progressive myelofibrosis. TSP-2 was barely detectable but 40% of cases with advanced myelofibrosis showed a strong expression. Megakaryocytes and interstitial proplatelet formations were shown to be the relevant source for TSP-1 in PMF. Stroma cells like endothelial cells and fibroblasts showed no TSP-1 labeling when double-immunofluorescence staining and CLSM were applied. Based on its dual function, TSP-1 in PMF is likely to be a mediator within a pro-fibrotic environment which discriminates from ET cases. On the other hand, TSP-1 is a factor acting (ineffectively) against exaggerated angiogenesis. Both features suggest TSP-1 to be a biomarker for monitoring a PMF-targeted therapy. [ABSTRACT FROM AUTHOR]

Abstract: The microRNA/miR system might contribute to deregulation of cell homeostasis/disease phenotype. This is the first approach to generate an expression profile of 365 microRNAs in myelodysplastic syndromes (MDS) with normal karyotype (n =12) and distinct cytogenetic aberrations (n =12). In MDS-del(5q), a series of microRNAs not in the 5q-region was increased. MicroRNAs encoded on chromosomes 5, 7 and 8 were not differentially expressed in MDS with del(5q), −7 or +8. Evaluation in a larger cohort could confirm the up-regulation of the miR-1 in MDS. These findings provide evidence that MDS-haematopoiesis is distinct in its microRNA-expression pattern from non-neoplastic cells. [ABSTRACT FROM AUTHOR]

Abstract: We investigated whether, in myelodysplastic syndromes (MDS), aberrant expression of miR-150/miR-221/miR-222 and their designated target mRNA molecules MYB, p27 and c-KIT may be involved in insufficient haematopoiesis. In a series of MDS (n =52), an aberrant increase of miR-150 was found only in MDS with associated del(5q) (n =9; p <0.01). The mRNA expression of transcription factor MYB, the designated target of miR-150, was shown to correlate inversely with the miR-150 level. Acute leukaemia evolving from MDS (n =11) showed significantly decreased levels of miR-221 but not miR-222. We conclude that inhibition of proliferation via over-expressed miR-150 might contribute to myelodysplastic haematopoiesis in MDS-del(5q). [Copyright &y& Elsevier]

Background: In damaged organs tissue repair and replacement of cells by connective tissue provokes a response of fibroblasts to cellular stress factors such as hypoxia. MicroRNAs (miRNA) are small non-coding RNA molecules which bind to their mRNA targets which eventually lead to repression of translation. Whether the response of fibroblasts to stress factors also involves the miRNA system is largely unknown. Results: By miRNA profiling we identified down-regulation of miRNA-449a/b expression in hypoxic fibroblasts. Specific miRNA inhibitors and mimics showed direct evidence for targeting the serine protease inhibitor (serpin) protein (SERPINE1; plasminogen activator inhibitor-1, PAI-1) by miRNA-449a/b leading to SERPINE1 mRNA and protein up- and down-regulation, respectively. SERPINE1 expression in vivo could be located predominantly in areas of fibrosis and remodeling. Conclusions: Our study offers serious lines of evidence for a novel hypoxia-dependent mechanism involving hypoxia-induced decrease of clustered miRNA-449a/b, hypoxia-induced amplification of concomitant increase of targeted SERPINE1 (PAI-1) and its overexpression in tissues showing a hypoxic environment. [ABSTRACT FROM AUTHOR]

Lck/yes-related novel (Lyn) tyrosine kinase overexpression has been suggested to be important for leukaemic cell growth making it an attractive target for therapy. By contrast, Lyn deficiency was shown to be responsible for a phenotype resembling myeloproliferative neoplasm (MPN) in mice. We aimed to shed more light on Lyn's role in haematological neoplasm and systematically investigated Lyn expression in MPN, acute and chronic leukaemia subtypes ( n = 236). On top, B-cell chronic lymphocytic leukaemia (B-CLL) and chronic myeloid leukaemia significantly overexpressed Lyn when compared to de novo acute lymphoblastic leukaemia, de novo acute myeloid leukaemia (AML) and Philadelphia-chromosome-negative myeloproliferative neoplasms ( p < 0.001). Most of acute leukaemia subtypes showed a notable down-regulation of Lyn mRNA but anyhow individual cases were labelled for the active form of Lyn protein. Intriguingly, secondary AML evolved in myelodysplastic syndromes revealed almost undetectable Lyn. Overexpression of Lyn in B-CLL was associated with a significant down-regulation of microRNA-337-5p suggesting that aberrant expression of this particular microRNA could be involved in post-transcriptional control of Lyn mRNA fate. We conclude that tyrosine kinase Lyn contributes to the malignant phenotype in certain leukaemia subtypes and therefore attracts targeted therapy. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Micro 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 ( n = 66). Furthermore, we tested a potential influence of cytoreductive treatment on miRNA expression in bone marrow cells during the course of Ph− MPN ( n = 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, JAK2V617F mutations or cytoreductive treatment (bone marrow cells) were observed. [ABSTRACT FROM AUTHOR]

Objective: In order to identify factors involved in the aberrantly regulated apoptosis of megakaryocytes in primary myelofibrosis (PMF), the mRNA expression of human megakaryocytes in situ was quantified by real-time polymerase chain reaction low-density arrays. Materials and Methods: The mRNA from 200 to 300 laser-microdissected megakaryocytes per case from PMF (n = 22) and control (n = 10) bone marrow was reverse-transcribed into cDNA by random priming and subsequently amplified by primer-specific cDNA amplification. The mRNA of corresponding total bone marrow cells was reverse-transcribed into cDNA without the following amplification. For relative mRNA quantification, custom-made TaqMan low-density arrays with a setup of 48 different genes were applied. In addition, methylation analysis and immunohistochemistry of a selected candidate gene were accomplished. Results: A trend toward an overall downregulation of apoptosis-associated genes could be observed in megakaryocytes, whereas the total bone marrow cellularity exhibited an overall upregulation of these factors. Among several candidates with statistically significant deregulation BCL2/adenovirus E1B 19 kDa interacting protein 3 (BNIP3) and protein kinase C β1 were shown to be the most aberrantly expressed genes. Conclusion: Apoptosis-related gene expression profiling of human megakaryocytes reveals a set of candidates, most notably BNIP3, indicating that the increase of megakaryocytes in myeloproliferative neoplasia might not only be the result of increased proliferation but also of disturbed apoptosis. [Copyright &y& Elsevier]

The role of telomerase catalytic subunit hTERT in clonal malignancies including human leukemia is fundamental in overcoming cell senescence and enabling prolonged proliferation. One direct transcriptional activator of hTERT is the oncogene MYC which is known to be, in turn, activated by JAK2. To explore the relationship of telomerase, MYC and JAK2 in chronic myeloproliferative diseases, we investigated hTERT and MYC expression in bone marrow cells of essential thrombocythemia (ET) and polycythemia vera (PV). We could determine an up-regulation of MYC expression exclusively in JAK2wt ET, whereas hTERT expression was rather inconsistent across the groups. Interestingly, a significant correlation between MYC and hTERT expression could only be established in homozygous JAK2V617F PV and control cases. Thus, the functional link between MYC and hTERT seems to be impaired depending on the molecular ET subtype, which in turn may have implications on the phenotype and course of the disease. [ABSTRACT FROM AUTHOR]

Atypical megakaryocytes provide the histomorphological hallmark of all Philadelphia-chromosome negative chronic myeloproliferative disorder (Ph− CMPD) subtypes and have not been studied so far for the JAK2V617F mutation. The mutant gene dosage was determined in isolated megakaryocytes from 68 cases of JAK2+/Ph− CMPD by a pyrosequencing assay. Megakaryocytes from essential thrombocythemia (ET) showed significantly lower levels of mutated JAK2 alleles compared to patients with chronic idiopathic myelofibrosis (cIMF) with manifest fibrosis and polycythemia vera (PV) but not to prefibrotic cIMF. Solely, ET JAK2V617F in megakaryocytes is associated with a PV-like phenotype, and at least in one patient, the JAK2 mutation was exclusively acquired within the megakaryocytic lineage. The overt differences between prefibrotic and fibrotic cIMF suggested a causative role of the gene dosage of mutant JAK2 in fibrotic progression. Megakaryocyte analysis of a follow-up of eight individual cases with sequential biopsies, however, showed that progression to homozygosity of V617F mutated JAK2 and onset of manifest fibrosis appeared to be independent events. We conclude that megakaryocytes might be the predominant or even the exclusive lineage that acquires the JAK2V617F mutation in ET and that the JAK2V617F evolution to higher gene dosages represents a dynamic and complex process substantially involving megakaryocytes. [ABSTRACT FROM AUTHOR]

The role of β-catenin in epithelial neoplasms has been widely studied whereas current knowledge regarding β-catenin gene and protein expression in bone marrow cells derived from normal haematopoiesis and clonal haematological disorders is lacking. β-Catenin gene expression was quantitatively investigated in bone marrow cells derived from clonal haematological disorders [acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL), Philadelphia chromosome-positive chronic myeloid leukaemia (Ph+ CML], Ph− myeloproliferative disorders, n = 96) compared with non-neoplastic haematopoiesis ( n = 33) by real-time reverse transcription polymerase chain reaction. Cellular localization of β-catenin protein was detected by immunocytochemistry. β-Catenin gene expression was significantly increased in AML compared with ALL cases ( P < 0·0001), Ph+ CML ( P < 0·0001) and non-neoplastic haematopoiesis ( P = 0·019). Immunocytochemistry revealed that, in non-neoplastic haematopoiesis, the granulopoietic lineage as well as megakaryocytes showed membranous and cytoplasmic staining to various degrees along with unlabelled nuclei. Besides haematopoiesis, β-catenin prominently marked bone marrow vascularity and diverse stroma cells. β-Catenin gene was inversely expressed in AML and ALL with a lack of protein expression in neoplastic cells in ALL. In contrast, the other haematological disorders under study, except for Ph+ CML, did not show significant alterations of overall β-catenin gene expression compared with normal bone marrow. These data suggest different regulatory mechanisms in the expression and function of β-catenin in haematopoietic cells. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which discusses the lineage involvement of the combined genetic mutation of MPLW515L and JAK2V617F in myelodysplastic/myeloproliferative disease.

A letter to the editor is presented regarding B-cell chronic lymphocytic leukaemia (B-CLL) developing in a patient with polycythemia vera (PV) who is not affected by V617F mutation of the Janus kinase 2.

Background: In damaged organs tissue repair and replacement of cells by connective tissue provokes a response of fibroblasts to cellular stress factors such as hypoxia.MicroRNAs (miRNA) are small non-coding RNA molecules which bind to their mRNA targets which eventually lead to repression of translation. Whether the response of fibroblasts to stress factors also involves the miRNA system is largely unknown.Results: By miRNA profiling we identified down-regulation of miRNA-449a/b expression in hypoxic fibroblasts. Specific miRNA inhibitors and mimics showed direct evidence for targeting the serine protease inhibitor (serpin) protein (SERPINE1; plasminogen activator inhibitor-1, PAI-1) by miRNA-449a/b leading to SERPINE1 mRNA and protein up- and down-regulation, respectively. SERPINE1 expression in vivo could be located predominantly in areas of fibrosis and remodeling.Conclusions: Our study offers serious lines of evidence for a novel hypoxia-dependent mechanism involving hypoxia-induced decrease of clustered miRNA-449a/b, hypoxia-induced amplification of concomitant increase of targeted SERPINE1 (PAI-1) and its overexpression in tissues showing a hypoxic environment. [ABSTRACT FROM AUTHOR]