Tetrasomy 13 as the sole cytogenetic abnormality in acute myeloid leukemia M1 without maturation

We report a case of acute myeloid leukemia (AML) M1 showing a 48,XY,+13,+13 karyotype. Treatment was according to the Medical Research Council AML14 trial protocol with two courses of DAT chemotherapy. Postchemotherapy bone marrow examination failed to show complete remission or cytogenetic normalization. Despite having resistant disease, the patient initially remained clinically well although requiring regular blood transfusions for anemia. However his leukocyte count gradually increased and he became symptomatic. He was treated subsequently with FLAG but died approximately 2 weeks later, 6 months after first presenting. Tetrasomy 13 as the sole cytogenetic abnormality has not been reported previously in M1 AML and has only been reported in three other AML cases, all with an immature phenotype and poor outcome.     

Activation of bone morphogenetic protein/Smad signaling in bronchial epithelial cells during airway inflammation

Bone morphogenetic proteins (BMPs) are pleiotropic secreted proteins, structurally related to transforming growth factor (TGF)-beta and activins. BMPs play pivotal roles in the regulation of embryonic lung development and branching of airways and have recently been considered to influence inflammatory processes in adults due to their chemotactic activity on fibroblasts, myocytes, and inflammatory cells. In this study, we have investigated the possible involvement of BMPs in a model of experimental allergic-airway inflammation in situ using antibodies that detect activated Smad proteins, and have monitored the modulation of BMP ligands during the inflammatory response. Inflamed bronchial epithelial cells and a few scattered alveolar cells expressed levels of phosphorylated Smad1 (pSmad1/5), indicative of active BMP/Smad signaling. This was in contrast to healthy epithelium, which was devoid of immunoreactivity. A mechanistic explanation for increased pSmad1/5 staining during inflammation was provided by the upregulated expression of all the BMP type I receptors, i.e., activin receptor-like kinase (ALK)2, ALK3, and ALK6, in the inflamed bronchial epithelial cells. Furthermore, the mRNA and protein profiles for BMP ligands were significantly altered during airway inflammation with induction of BMP2, BMP4, and BMP6, and downregulation of BMP5 and BMP7. Collectively, our data demonstrate for the first time active BMP/Smad signaling during airway inflammation in bronchial epithelial cells and thus raise the possibility that BMPs could play a determining role in respiratory pathophysiology.     

Synthesis and characterisation of poly(arylene sulfides), 6. Synthesis of block copoly(arylene sulfides)

Novel ABA block copolymers of poly(1,4-phenylene sulfide) (PPS(A)) and poly-(2-methyl-1,4-phenylene sulfide) (PMPS(B)) were synthesised from bis(4-bromophenyl) sulfone (BBS) by sequential reaction with copper(I) 4-bromo-2-methylbenzenethiolate (CBMT) and copper(I) 4-bromobenzenethiolate (CBT). PPS, PMPS and PPS/PMPS random copolymers were also prepared to aid block copolymer characterisation. Polymer fractions were studied by hot-stage microscopy to evaluate melting ranges, and molar masses were computed from bromine end-group concentrations and from gel permeation chromatography studies. Compositional analyses were made by IR and ¹H NMR spectroscopy leading to confirmation of the block copolymer structure and to evaluation of the degrees of polymerisation of the individual blocks.     

High expression of MDR1, MRP1, and MRP3 in the hepatic progenitor cell compartment and hepatocytes in severe human liver disease

An increase in bile ductular structures is observed in diverse human liver diseases. These structures harbour the progenitor cell compartment of the liver. Since ATP-binding cassette (ABC) transporters may have a cytoprotective role in liver disease, an immunohistochemical study was performed on human liver specimens from patients with primary biliary cirrhosis (PBC), chronic hepatitis C virus (HCV) infection, submassive cell necrosis, and normal liver. The expression of MDR1, MDR3, BSEP, MRP1, MRP2, and MRP3 was determined using specific antibodies. Dilution series were constructed to determine the critical staining level in order to estimate the factor of up-regulation. In normal liver, hepatocytes showed canalicular staining for MDR3, BSEP, and MRP2. MDR1 stained the canalicular membrane of hepatocytes as well as that of cholangiocytes. MRP3 showed low immunoreactivity of bile duct epithelial cells and centrilobular hepatocytes only. Normal liver showed no immunoreactivity for MRP1. In diseased liver, the expression of MDR3, BSEP, and MRP2 was relatively stable. In PBC, HCV, and submassive necrosis, the expression levels of MDR1, MRP1, and MRP3 were increased. The strongest immunoreactivity was seen after submassive necrosis, where remaining islands of hepatocytes showed strong canalicular staining for MDR1 and MRP3. Regenerating bile ductules at the interface of portal tracts and necrotic areas stained intensely for MDR1, MRP1, and MRP3. In conclusion, MDR1, MRP1, and MRP3 are up-regulated in hepatocytes in severe human liver disease. Strong MDR1, MRP1, and MRP3 reactivity is seen in regenerating human bile ductules.     

Nerve growth factor (NGF) promotes angiogenesis in the quail chorioallantoic membrane.

Angiogenesis, the formation of new blood vessels, is tightly regulated by growth factors, such as vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF). The authors hypothesize that nerve growth factor (NGF), a well known neurotrophin, may play a direct angiogenic role. To test this hypothesis, the authors measured the effects of NGF on the natural vascularization of the quail chorioallantoic membrane (CAM). The angiogenic effect of NGF was compared to that of human recombinant VEGF165 (rhVEGF) and basic FGF (rhbFGF). In comparison to phosphate-buffered saline-treated controls, NGFs from different biological sources (mouse, viper, and cobra) increased the rate of angiogenesis in a dose-dependent fashion from 0.5 to 5 microg. For quantitative morphometry, grayscale images of the blood vessels end points of the CAM arteries were binarized for visualization and skeletonized for quantization by fractal analysis. In mouse NGF-treated embryos the fractal dimension (Df), indicative of arterial vessel length and density, increased to 1.266 +/- 0.021 compared to 1.131 +/- 0.018 (p < .001) for control embryos. This effect was similar to that of 0.5 microg rhVEGF (1.290 +/- 0.021, p < .001) and 1.5 microg rhbFGF (1.264 +/- 0.028, p < .001). The mouse NGF-induced angiogenic effect was blocked by 1 microM K252a (1.149 +/- 0.018, p < .001), an antagonist of the NGF/trkA receptor, but not by 1 microM SU-5416 (1.263 +/- 0.029, p < .001), the VEGF/Flk1 receptor antagonist, indicating a direct, selective angiogenic effect of NGF via quail embryo trkA receptor activation. These results confirm previous observations that NGF has angiogenic activity and suggest that this neurotrophin may also play an important role in the cardiovascular system, besides its well-known effects in the nervous system. The angiogenic properties of NGF may be beneficial in engineering new blood vessels and for developing novel antiangiogenesis therapies for cancer.     

Gains of 13q are correlated with a poor prognosis in liposarcoma.

Liposarcomas are a phenotypical heterogeneous group of tumors divided into four main subtypes: well-differentiated, dedifferentiated, myxoid/round cell, and pleomorphic. The aim of this study was to compare DNA sequence copy number changes of these subtypes as investigated by comparative genomic hybridization in 36 patients. Comparative genomic hybridization revealed genomic imbalances in tumors of 27 patients (mean 5.6 imbalances per tumor). The most frequent gains were within single regions of 1q, 12q, and 13q. We found a significant correlation of poor overall survival and gain of 13q21 (P=0.0221), 13q22 (P=0.0341), 13q31 (P=0.0410), and 13q32 (P=0.0074). The univariate Cox regression analysis revealed an increased risk of tumor-related death for patients whose liposarcomas possess with gains of 13q21 and 13q32 simultaneously (P=0.010; RR=7.1; 95% CI 1.6-31.7). Furthermore, 12 high-level amplifications were found in tumors of seven patients. In four cases 12q14-q15 and in two cases 13q32-q33 were amplified. We identified in different liposarcoma subtypes characteristic genomic changes: Gains and high-level amplifications of 12q occurred in all 11 investigated well-differentiated liposarcomas, and these changes were often present simultaneously with gains of 1q (mean 5.5 changes). In the two dedifferentiated liposarcomas, gains of 1q in both liposarcomas, and a high-level amplification of 13q were striking. Only eight of the 17 patients with myxoid/round cell liposarcomas showed changes in DNA copy number (mean 3.4 imbalances). In four of these eight cases gains of 13q occurred. The six pleomorphic liposarcomas possessed the most frequent genomic imbalances (mean number 16.3) of all liposarcoma subtypes investigated. These imbalances were in almost all chromosomal regions detected predominantly as over-representations of chromosomes 1, 5p, 13q, and 22q. Summarizing, all subtypes but well-differentiated liposarcomas showed gains of 13q, which were associated with a poor prognosis.     

Characterization of wild-type recombinant Bet v 1a as a candidate vaccine against birch pollen allergy

BACKGROUND: We describe the production in Escherichia coli as a recombinant protein of clinical grade wild-type Bet v 1a (rBet v 1a), to be used as a candidate vaccine against birch pollen allergy. METHODS: This recombinant protein was purified by hydrophobic interaction and ion exchange chromatography and characterized by SDS-PAGE, immunoprint and circular dichroism in parallel with natural Bet v 1 (nBet v 1) purified from a birch pollen extract. We also compared rBet v 1 and nBet v 1 for their capacity to induce histamine release from basophils and to stimulate T lymphocyte proliferation. RESULTS: rBet v 1a appears in SDS-PAGE as an 18-kDa monomeric protein, whereas purified nBet v 1 comprises a mixture of isoforms (resolving as three distinct bands and six spots after 1-dimensional and 2-dimensional electrophoresis, respectively). Both recombinant and natural purified Bet v 1 molecules are recognized by IgE from birch pollen-allergic patients as well as anti-Bet v 1 murine monoclonal antibodies, suggesting that the recombinant protein is correctly folded in a native configuration. Circular dichroism analysis confirmed that the two Bet v 1 molecules exhibit similar 3-dimensional structures, even if rBet v 1a appears more compact and stable in thermodenaturation/renaturation experiments. Both rBet v 1 and nBet v 1 induce the degranulation of sensitized basophils and proliferation of Bet v 1-specific T lymphocytes in a similar manner. CONCLUSIONS: On the basis of these structural and biological properties, rBet v 1a is a valid candidate vaccine against birch pollen allergy, currently evaluated in humans.     

Lymphatic endothelial cell identity is reversible and its maintenance requires Prox1 activity

The activity of the homeobox gene Prox1 is necessary and sufficient for venous blood endothelial cells (BECs) to acquire a lymphatic endothelial cell (LEC) fate. We determined that the differentiated LEC phenotype is a plastic, reprogrammable condition that depends on constant Prox1 activity for its maintenance. We show that conditional down-regulation of Prox1 during embryonic, postnatal, or adult stages is sufficient to reprogram LECs into BECs. Consequently, the identity of the mutant lymphatic vessels is also partially reprogrammed as they acquire some features typical of the blood vasculature. siRNA-mediated down-regulation of Prox1 in LECs in culture demonstrates that reprogramming of LECs into BECs is a Prox1-dependent, cell-autonomous process. We propose that Prox1 acts as a binary switch that suppresses BEC identity and promotes and maintains LEC identity; switching off Prox1 activity is sufficient to initiate a reprogramming cascade leading to the dedifferentiation of LECs into BECs. Therefore, LECs are one of the few differentiated cell types that require constant expression of a certain gene to maintain their phenotypic identity.     

Cellular nonmuscle myosins NMHC‐IIA and NMHC‐IIB and vertebrate heart looping

Flectin, a protein previously described to be expressed in a left‐dominant manner in the embryonic chick heart during looping, is a member of the nonmuscle myosin II (NMHC‐II) protein class. During looping, both NMHC‐IIA and NMHC‐IIB are expressed in the mouse heart on embryonic day 9.5. The patterns of localization of NMHC‐IIB, rather than NMHC‐IIA in the mouse looping heart and in neural crest cells, are equivalent to what we reported previously for flectin. Expression of full‐length human NMHC‐IIA and ‐IIB in 10 T1/2 cells demonstrated that flectin antibody recognizes both isoforms. Electron microscopy revealed that flectin antibody localizes in short cardiomyocyte cell processes extending from the basal layer of the cardiomyocytes into the cardiac jelly. Flectin antibody also recognizes stress fibrils in the cardiac jelly in the mouse and chick heart; while NMHC‐IIB antibody does not. Abnormally looping hearts of the Nodal^{Δ 600} homozygous mouse embryos show decreased NMHC‐IIB expression on both the mRNA and protein levels. These results document the characterization of flectin and extend the importance of NMHC‐II and the cytoskeletal actomyosin complex to the mammalian heart and cardiac looping. Developmental Dynamics 237:3577–3590, 2008. © 2008 Wiley‐Liss, Inc.     

An evaluation of semen analysis and in-vitro tests of sperm function in the prediction of the outcome of intrauterine AIH

Twenty-nine couples with an average of 5 years of infertilitywere selected for treatment by intrauterine insemination ofwashed semen (AIH). The criteria for selection were (i) thefemale partner showed no detectable fertility disorders by routinescreening; (ii) the male partner showed subnormal semen qualityon conventional semen analysis. Ovulation was stimulated uniformlywith clomiphene citrate and precipitated with human chorionicgonadotrophin (HCG). Inseminations were performed 31–32h post-HCG, with the day of HCG determined by ultrasound monitoringof follicular development. The fertilizing capacity of the malepartners‘ spermatozoa was tested in vitro using donatedhuman oocytes and/or the zona-free hamster oocyte penetrationassay. Up to eight cycles of AIH were alternated with cyclesof natural intercourse. While no pregnancies occurred in thegroup during normal coital cycles, the AIH pregnancy rate was17% per couple, but only 3% per insemination cycle. Four furtherpregnancies were achieved spontaneously in couples from thestudy group within 3 years of completion of the AIH therapyand four patients became pregnant following subsequent GIFTor IVF treatments. Neither of the in-vitro tests was helpfulin predicting the outcome of AIH, spontaneous pregnancy norof subsequent assisted conception procedures.