Poisson-Lie T-dual sigma models on supermanifolds

We investigate Poisson-Lie symmetry for T-dual sigma models on supermanifolds in general and on Lie supergroups in particular. We show that the integrability condition on this super Poisson-Lie symmetry is equivalent to the super Jacobi identities of the Lie super-bialgebras. As examples we consider models related to four dimensional Lie super-bialgebras $((2A1,1 + 2A)^1, D10_p=1/2)$ and $((2A1,1 + 2A)^1, I)$. Then generally it is shown that for Abelian case (g, I) the super Poisson-Lie T-duality transforms the role of fermionic (bosonic) fields in the model to bosonic (fermionic) fields on the dual model and vice versa.Comment: 13 pages, Revised and accepted for publication in JHE

On cohomological dimension and depth under linkage

Some relations between cohomological dimensions and depths of linked ideals are investigated and discussed by various examples.Comment: 7 page

String cosmology from Poisson-Lie T-dual sigma models on supermanifolds

We generalize the formulation of Poisson-Lie T-dual sigma models on manifolds to supermanifolds. In this respect, we formulate 1+1 dimensional string cosmological models on the Lie supergroup C^3 and its dual (A_1,1 + 2A)^0_(1,0,0), which are coupled to two fermionic fields. Then, we solve the equations of motion of the models and show that there is a essential singularity for the metric of the original model and its dual.Comment: 17 pages, Appendix and three references have adde

Extending the functionalities of shear-driven chromatography nano-channels using high aspect ratio etching

An new injection system is presented for shear-driven chromatography. The device has been fabricated by high aspect ratio etching of silicon. The performance of the injection slit is studied through the aid of computational fluid dynamics, and the first experimental results are presented

Gonadal function in males after chemotherapy for early-stage Hodgkin's lymphoma treated in four subsequent trials by the European Organisation for Research and Treatment of Cancer: EORTC Lymphoma Group and the Groupe d'Etude des Lymphomes de l'Adulte.

Contains fulltext : 51705.pdf (publisher's version ) (Open Access)PURPOSE: To analyze fertility in male patients treated with various combinations of radiotherapy and chemotherapy, with or without alkylating agents, or with radiotherapy alone for Hodgkin's lymphoma. PATIENTS AND METHODS: Follicle-stimulating hormone (FSH) levels were measured in patients with early-stage upper-diaphragmatic disease enrolled in four European Organisation for Research and Treatment of Cancer (EORTC) trials (H6-H9). Median follow-up after therapy was 32 months. Patients with FSH measurement at least 12 months after end of treatment (n = 355) were selected to assess post-treatment fertility. Patients with FSH measurement 0 to 9 months after therapy (n = 349) were selected to analyze fertility recovery; of these, patients with elevated FSH (> 10 U/L; n = 101) were followed until recovery. Factors predictive for therapy-related infertility were assessed by logistic regression. RESULTS: The proportion of elevated FSH was 3% and 8% in patients treated with radiotherapy only or with nonalkylating chemotherapy (doxorubicin, bleomycin, vinblastine, dacarbazine [ABVD], epirubicin, bleomycin, vinblastine, prednisone [EBVP]); it was 60% (P < .001) after chemotherapy containing alkylating agents (mechlorethamine, vincristine, procarbazine, prednisone [MOPP], MOPP/doxorubicin, bleomycin, vinblastine [ABV], bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone [BEACOPP]). After a median time of 19 months, recovery of fertility occurred in 82% of patients treated without alkylating chemotherapy. This proportion was 30%, statistically (P < .001) lower in those treated with alkylating chemotherapy, and median time to recovery was 27 months. The post-treatment proportion of elevated FSH increased significantly (P < .001) with the dose of alkylating chemotherapy administered, and recovery was less frequent and slower after higher doses. Age more than 50 years and stage II disease also contributed to poor outcome. CONCLUSION: Fertility can be secured after nonalkylating chemotherapy for Hodgkin's lymphoma. In contrast, alkylating chemotherapy has a dismal effect, even after a limited number of cycles

Phase Behavior of Polyelectrolyte Block Copolymers in Mixed Solvents

We have studied the phase behavior of the poly(n-butyl acrylate)-b-poly(acrylic acid) block copolymer in a mixture of two miscible solvents, water and tetrahydrofuran (THF). The techniques used to examine the different polymers, structures and phases formed in mixed solvents were static and dynamic light scattering, small-angle neutron scattering, nuclear magnetic resonance and fluorescence microscopy. By lowering the water/THF mixing ratio X, the sequence unimers, micron-sized droplets, polymeric micelles was observed. The transition between unimers and the micron-sized droplets occurred at X = 0.75, whereas the microstructuration into core-shell polymeric micelles was effective below X = 0.4. At intermediate mixing ratios, a coexistence between the micron-sized droplets and the polymeric micelles was observed. Combining the different aforementioned techniques, it was concluded that the droplet dispersion resulted from a solvent partitioning that was induced by the hydrophobic blocks. Comparison of poly(n-butyl acrylate) homopolymers and poly(n-butyl acrylate)-b-poly(acrylic acid) block copolymers suggested that the droplets were rich in THF and concentrated in copolymers and that they were stabilized by the hydrophilic poly(acrylic acid) moieties.Comment: 11 pages, 12 figures, to appear in Macromolecule

The effect of bisphosphonate treatment on osteoclast precursor cells in postmenopausal osteoporosis: The TRIO study

Bisphosphonates are used to treat bone disease characterised by increased bone resorption by inhibiting the activity of mature osteoclasts, resulting in decreased bone turnover. Bisphosphonates may also reduce the population of osteoclast precursor cells. Our aims were to investigate the effect of bisphosphonates on i) osteoclast precursor cells and ii) circulating cytokine and cytokine receptor in postmenopausal women with osteoporosis compared with healthy premenopausal women. Participants were 62 postmenopausal women (mean age 66) from a 48-week parallel group trial of bisphosphonates. They received ibandronate 150 mg/month (n = 22), alendronate 70 mg/week (n = 19) or risedronate 35 mg/week (n = 21). Fasting blood was collected at baseline, weeks 1 and 48. At baseline, blood was also collected from 25 healthy premenopausal women (mean age 37) to constitute a control group. Peripheral blood mononuclear cells were extracted and stained for CD14, M-CSFR, CD11b and TNFRII receptors. Flow cytometry was used to identify cells expressing CD14 + and M-CSFR + or CD11b + or TNFRII +. RANKL and OPG were measured to evaluate potential mediation of the bisphosphonate effect. After 48 weeks of treatment, there was a decrease in the percentage of cells expressing M-CSFR and CD11b receptors by 53% and 49% respectively (p < 0.01). Cells expressing M-CSFR and CD11b were decreased with ibandronate and risedronate after 48 weeks to the lower part of the premenopausal reference interval. These effects were not significantly different between each of the treatment groups. There was no significant effect on RANKL and OPG throughout the study period. Bisphosphonates inhibit bone resorption in the short-term by direct action on mature osteoclasts. There is also a later effect mediated in part by a reduction in the population of circulating osteoclast precursors

Apoptosis, autophagy and ER stress in mevalonate cascade inhibition-induced cell death of human atrial fibroblasts

3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitors (statins) are cholesterol-lowering drugs that exert other cellular effects and underlie their beneficial health effects, including those associated with myocardial remodeling. We recently demonstrated that statins induces apoptosis and autophagy in human lung mesenchymal cells. Here, we extend our knowledge showing that statins simultaneously induces activation of the apoptosis, autophagy and the unfolded protein response (UPR) in primary human atrial fibroblasts (hATF). Thus we tested the degree to which coordination exists between signaling from mitochondria, endoplasmic reticulum and lysosomes during response to simvastatin exposure. Pharmacologic blockade of the activation of ER-dependent cysteine-dependent aspartate-directed protease (caspase)-4 and lysosomal cathepsin-B and -L significantly decreased simvastatin-induced cell death. Simvastatin altered total abundance and the mitochondrial fraction of proapoptotic and antiapoptotic proteins, while c-Jun N-terminal kinase/stress-activated protein kinase mediated effects on B-cell lymphoma 2 expression. Chemical inhibition of autophagy flux with bafilomycin-A1 augmented simvastatin-induced caspase activation, UPR and cell death. In mouse embryonic fibroblasts that are deficient in autophagy protein 5 and refractory to autophagy induction, caspase-7 and UPR were hyper-induced upon treatment with simvastatin. These data demonstrate that mevalonate cascade inhibition-induced death of hATF manifests from a complex mechanism involving co-regulation of apoptosis, autophagy and UPR. Furthermore, autophagy has a crucial role in determining the extent of ER stress, UPR and permissiveness of hATF to cell death induced by statins

γ-Aminobutyric acid (GABA) signalling in human pancreatic islets is altered in type 2 diabetes

AIMS/HYPOTHESIS: γ-Aminobutyric acid (GABA) is a signalling molecule in the interstitial space in pancreatic islets. We examined the expression and function of the GABA signalling system components in human pancreatic islets from normoglycaemic and type 2 diabetic individuals. METHODS: Expression of GABA signalling system components was studied by microarray, quantitative PCR analysis, immunohistochemistry and patch-clamp experiments on cells in intact islets. Hormone release was measured from intact islets. RESULTS: The GABA signalling system was compromised in islets from type 2 diabetic individuals, where the expression of the genes encoding the α1, α2, β2 and β3 GABA(A) channel subunits was downregulated. GABA originating within the islets evoked tonic currents in the cells. The currents were enhanced by pentobarbital and inhibited by the GABA(A) receptor antagonist, SR95531. The effects of SR95531 on hormone release revealed that activation of GABA(A) channels (GABA(A) receptors) decreased both insulin and glucagon secretion. The GABA(B) receptor antagonist, CPG55845, increased insulin release in islets (16.7 mmol/l glucose) from normoglycaemic and type 2 diabetic individuals. CONCLUSIONS/INTERPRETATION: Interstitial GABA activates GABA(A) channels and GABA(B) receptors and effectively modulates hormone release in islets from type 2 diabetic and normoglycaemic individuals