The Agony of Love and Fear: Nazism and the German Queer Community, 1920-1945

The Nazis’ persecution of LGBTQ individuals is an often-overlooked topic in the wider study of theSecond World War. This paper synthesises recent research on this subject to provide an introductionto queer life in Germany between 1920 and 1945; it deals largely with the lives and experiences of gaymen, particularly their fight for legal equality in the interwar years and their mistreatment during the Naziperiod. Although not aiming to break new ground in this field, this paper aims to raise awareness of andgenerate interest in this topic among a general, interdisciplinary audience, and also to remind readersthat the struggles faced by the worldwide queer community neither began nor ended with the Third Reich

Effects of Atrazine Exposure on Human Bone Marrow-derived Mesenchymal Stromal Cells Assessed by Combinatorial Assay Matrix

INTRODUCTION: Mesenchymal Stromal/Stem cells (MSCs) are an essential component of the regenerative and immunoregulatory stem cell compartment of the human body and thus of major importance in human physiology. The MSCs elicit their beneficial properties through a multitude of complementary mechanisms, which makes it challenging to assess their phenotype and function in environmental toxicity screening. We here employed the novel combinatorial assays matrix approach/technology to profile the MSC response to the herbicide Atrazine, which is a common environmental xenobiotic, that is in widespread agricultural use in the US and other countries, but banned in the EU. Our here presented approach is representative for screening the impact of environmental xenobiotics and toxins on MSCs as an essential representative component of human physiology and well-being. METHODS: We here employed the combinatorial assay matrix approach, including a panel of well standardized assays, such as flow cytometry, multiplex secretome analysis, and metabolic assays, to define the phenotype and functionality of human-donor-derived primary MSCs exposed to the representative xenobiotic Atrazine. This assay matrix approach is now also endorsed for characterization of cell therapies by leading regulatory agencies, such as FDA and EMA. RESULTS: Our results show that the exposure to Atrazine modulates the metabolic activity, size, and granularity of MSCs in a dose and time dependent manner. Intriguingly, Atrazine exposure leads to a broad modulation of the MSCs secretome (both upregulation and downmodulation of certain factors) with the identification of Interleukin-8 as the topmost upregulated representative secretory molecule. Interestingly, Atrazine attenuates IFNγ-induced upregulation of MHC-class-II, but not MHC-class-I, and early phosphorylation signals on MSCs. Furthermore, Atrazine exposure attenuates IFNγ responsive secretome of MSCs. Mechanistic knockdown analysis identified that the Atrazine-induced effector molecule Interleukin-8 affects only certain but not all the related angiogenic secretome of MSCs. DISCUSSION: The here described Combinatorial Assay Matrix Technology identified that Atrazine affects both the innate/resting and cytokine-induced/stimulated assay matrix functionality of human MSCs, as identified through the modulation of selective, but not all effector molecules, thus vouching for the great usefulness of this approach to study the impact of xenobiotics on this important human cellular subset involved in the regenerative healing responses in humans

Metabolic Effects of Acute Thiamine Depletion Are Reversed by Rapamycin in Breast and Leukemia Cells

Thiamine-dependent enzymes (TDEs) control metabolic pathways that are frequently altered in cancer and therefore present cancer-relevant targets. We have previously shown that the recombinant enzyme thiaminase cleaves and depletes intracellular thiamine, has growth inhibitory activity against leukemia and breast cancer cell lines, and that its growth inhibitory effects were reversed in leukemia cell lines by rapamycin. Now, we first show further evidence of thiaminase therapeutic potential by demonstrating its activity against breast and leukemia xenografts, and against a primary leukemia xenograft. We therefore further explored the metabolic effects of thiaminase in combination with rapamycin in leukemia and breast cell lines. Thiaminase decreased oxygen consumption rate and increased extracellular acidification rate, consistent with the inhibitory effect of acute thiamine depletion on the activity of the TDEs pyruvate dehydrogenase and 2-oxoglutarate dehydrogenase complexes; these effects were reversed by rapamycin. Metabolomic studies demonstrated intracellular thiamine depletion and the presence of the thiazole cleavage product in thiaminase-treated cells, providing validation of the experimental procedures. Accumulation of ribose and ribulose in both cell lines support the thiaminase-mediated suppression of the TDE transketolase. Interestingly, thiaminase suppression of another TDE, branched chain amino ketoacid dehydrogenase (BCKDH), showed very different patterns in the two cell lines: in RS4 leukemia cells it led to an increase in BCKDH substrates, and in MCF-7 breast cancer cells it led to a decrease in BCKDH products. Immunoblot analyses showed corresponding differences in expression of BCKDH pathway enzymes, and partial protection of thiaminase growth inhibition by gabapentin indicated that BCKDH inhibition may be a mechanism of thiaminase-mediated toxicity. Surprisingly, most of thiaminase-mediated metabolomic effects were also reversed by rapamycin. Thus, these studies demonstrate that acute intracellular thiamine depletion by recombinant thiaminase results in metabolic changes in thiamine-dependent metabolism, and demonstrate a previously unrecognized role of mTOR signaling in the regulation of thiamine-dependent metabolism

Effects of Atrazine exposure on human bone marrow-derived mesenchymal stromal cells assessed by combinatorial assay matrix

IntroductionMesenchymal Stromal/Stem cells (MSCs) are an essential component of the regenerative and immunoregulatory stem cell compartment of the human body and thus of major importance in human physiology. The MSCs elicit their beneficial properties through a multitude of complementary mechanisms, which makes it challenging to assess their phenotype and function in environmental toxicity screening. We here employed the novel combinatorial assays matrix approach/technology to profile the MSC response to the herbicide Atrazine, which is a common environmental xenobiotic, that is in widespread agricultural use in the US and other countries, but banned in the EU. Our here presented approach is representative for screening the impact of environmental xenobiotics and toxins on MSCs as an essential representative component of human physiology and well-being.MethodsWe here employed the combinatorial assay matrix approach, including a panel of well standardized assays, such as flow cytometry, multiplex secretome analysis, and metabolic assays, to define the phenotype and functionality of human-donor-derived primary MSCs exposed to the representative xenobiotic Atrazine. This assay matrix approach is now also endorsed for characterization of cell therapies by leading regulatory agencies, such as FDA and EMA.ResultsOur results show that the exposure to Atrazine modulates the metabolic activity, size, and granularity of MSCs in a dose and time dependent manner. Intriguingly, Atrazine exposure leads to a broad modulation of the MSCs secretome (both upregulation and downmodulation of certain factors) with the identification of Interleukin-8 as the topmost upregulated representative secretory molecule. Interestingly, Atrazine attenuates IFNγ-induced upregulation of MHC-class-II, but not MHC-class-I, and early phosphorylation signals on MSCs. Furthermore, Atrazine exposure attenuates IFNγ responsive secretome of MSCs. Mechanistic knockdown analysis identified that the Atrazine-induced effector molecule Interleukin-8 affects only certain but not all the related angiogenic secretome of MSCs.DiscussionThe here described Combinatorial Assay Matrix Technology identified that Atrazine affects both the innate/resting and cytokine-induced/stimulated assay matrix functionality of human MSCs, as identified through the modulation of selective, but not all effector molecules, thus vouching for the great usefulness of this approach to study the impact of xenobiotics on this important human cellular subset involved in the regenerative healing responses in humans

Pregnane X receptor regulates drug metabolism and transport in the vasculature and protects from oxidative stress

Aims Circulating endogenous, dietary and foreign chemicals can contribute to vascular dysfunction. The mechanism by which the vasculature protects itself from these chemicals is unknown. This study investigates whether the pregnane X receptor (PXR), the major transcriptional regulator of hepatic drug metabolism and transport that responds to such xenobiotics, mediates vascular protection by co-ordinating a defence gene program in the vasculature.Methods and Results PXR was detected in primary human and rat aortic endothelial and smooth muscle cells and blood vessels including human and rat aorta. Metabolic PXR target genes cytochrome P450 3A, 2B, 2C and glutathione-S-transferase mRNA and activity were induced by PXR ligands in rodent and human vascular cells and absent in the aortas from PXR null mice stimulated in vivo or in rat aortic smooth muscle cells expressing dominant negative PXR. Activation of aortic PXR by classical agonists had several protective effects; increased xenobiotic metabolism demonstrated by bio-activation of the pro-drug clopidogrel, which reduced adenosine diphosphate-induced platelet aggregation; increased expression of multidrug resistance protein 1, mediating chemical efflux from the vasculature; and protection from reactive oxygen species-mediated cell death.Conclusions PXR co-ordinately up-regulates drug metabolism, transport and anti-oxidant genes to protect the vasculature from endogenous and exogenous insults, thus representing a novel gatekeeper for vascular defence

Self-Assembled Polymeric Micellar Nanoparticles as Nanocarriers for Poorly Soluble Anticancer Drug Ethaselen

A series of monomethoxy poly(ethylene glycol)-poly(lactide) (mPEG-PLA) diblock copolymers were synthesized, and mPEG-PLA micelle was fabricated and used as a nanocarrier for solubilization and delivery of a promising anticancer drug ethaselen. Ethaselen was efficiently encapsulated into the micelles by the dialysis method, and the solubility of ethaselen in water was remarkably increased up to 82 μg/mL before freeze-drying. The mean diameter of ethaselen-loaded micelles ranged from 51 to 98 nm with a narrow size distribution and depended on the length of PLA block. In vitro hemolysis study indicated that mPEG-PLA copolymers and ethaselen-loaded polymeric micelles had no hemolytic effect on the erythrocyte. The enhanced antitumor efficacy and reduced toxic effect of ethaselen-loaded polymeric micelle when compared with ethaselen-HP-β-CD inclusion were observed at the same dose in H22human liver cancer cell bearing mouse models. These suggested that mPEG-PLA polymeric micelle nanoparticles had great potential as nanocarriers for effective solubilization of poorly soluble ethaselen and further reducing side effects and toxicities of the drug

Effect of amphiphilic diblock copolymers on P-glycoprotein substrate permeability in Caco-2 cells

A series of short block length methoxypoly(ethylene g\yco\)-blockpoly( caprolactone) (MePEG-b-PCL) diblock copolymers were synthesized, characterized and evaluated for enhancing the permeability of P-gp substrates in an intestinal epithelial cell line, caco-2. Altering MePEG:caprolactone feed weight ratios produced diblocks composed of varying PCL lengths, with MePEG of MW 550, 750 or 2000. The diblocks formed micelles above the critical micelle concentration (CMC) values and hydrophobicity, solubility, CMC, and micelle size, were dependent on the block lengths of the diblock copolymers. Caco-2 cellular accumulation studies with two homologous P-glycoprotein substrates, rhodamine 123 (R-123) and rhodamine 6G (R-6G), showed that accumulation of the relatively hydrophilic P-gp substrate, R-123, was enhanced at high concentrations of MePEG-b-PCL diblock copolymers above their CMC with little activity below the CMC. Whereas, cellular accumulation with the relatively hydrophobic substrate, R-6G, was maximally enhanced over a wide range of diblock concentrations, lower or close to the CMC and which also corresponded to an 8-25 fold reduction in diblock concentration compared to R-123. Diblocks with intermediate to high HLB values were more effective at enhancing R- 123 accumulation, while all diblocks were shown to enhance R-6G accumulation. Similar accumulation enhancement profiles with MePEG-b-PCL were observed with two additional P-gp substrates, doxorubicin and paclitaxel, which have large differences in their relative hydrophobicities. At high diblock copolymer concentrations, R-123 and R-6G accumulation decreased and was likely due to substantial partitioning of R-123 and R-6G into micelles, reducing the free fraction available for cellular uptake. A substantially different rate of substrate accumulation with MePEG-b-PCL was observed depending upon the hydrophobicity of the P-gp substrate. MePEG-b-PCL diblocks increased the rate and extent of R-123 accumulation, but not the rate of accumulation of R-6G. The difference in MePEG-b-PCL diblock composition and concentrations required to enhance the accumulation of P-gp substrates with different relative hydrophobicities suggests that additional pathways may be involved besides a reduction of P-gp mediated efflux. To determine the cellular uptake pathways contributing to enhanced caco-2 cellular accumulation of P-gp substrates by MePEG-b-PCL block copolymers, the effects of endocytosis inhibitors, ATP depletion conditions, and directional transepithelial flux experiments were performed. For the hydrophilic R-123, MePEG₁₇-b-PCL₅ enhanced the cellular accumulation of R-123 at high concentrations of diblock above the CMC, which did not appear to involve endocytosis of micellized R-123. This suggests that MePEG₁₇-b-PCL₅ micelles may provide a 'depot' for free unimer to interact with the cell membrane and contribute either to enhanced passive transmembrane diffusion of R-123 through membrane permeability changes, or inhibition of P-gp mediated efflux, or both. In the secretory direction, diblock was capable of reducing the efflux of both R-123 and R-6G. However, MePEG₁₇-b-PCL₅ greatly enhanced the cellular accumulation of R-123 in the transepithelial directional flux studies in the absence of an increase in the absorptive flux. It is proposed that the basolateral membrane permeability of R-123 may limit the absorptive flux. In contrast, MePEG₁₇-b-PCL₅ was able to enhance the absorptive flux of the hydrophobic R-6G. ATP depletion studies demonstrated that MePEG₁₇-b-PCL₅ increased the accumulation of R-123 possibly through a membrane permeabilization effect. Erythrocyte hemolysis studies also provided evidence that MePEG₁₇-b-PCL₅ caused membrane perturbation effects, which could result in enhanced transmembrane diffusion of R-123.Pharmaceutical Sciences, Faculty ofGraduat

Compacting Object Code via Parameterized Procedural Abstraction

ion by Michael Joseph Zastre B.Sc., Simon Fraser University, 1993 A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE in the Department of Computer Science We accept this thesis as conforming to the required standard ________________________________________________________________ Dr. R. N. Horspool, Supervisor (Dept. of Computer Science) ________________________________________________________________ Dr. D. M. Hoffman (Dept. of Computer Science) ________________________________________________________________ Dr. G. C. Shoja (Dept. of Computer Science) ________________________________________________________________ Dr. R. Vahldieck (Dept. of Electrical and Computer Engineering) Ó Michael Joseph Zastre, 1995 University of Victoria All rights reserved. This thesis may not be reproduced in whole or in part, by photocopying or other means, without the permission of the author. ii Supervisor: Dr. R. N. Horspool Abstract Current compiler ..