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International Immunology Aug 2017Autoimmune and inflammatory conditions are frequent complications in patients with reduced numbers of T cells. Here, we describe a mouse model of thymic stromal...
Autoimmune and inflammatory conditions are frequent complications in patients with reduced numbers of T cells. Here, we describe a mouse model of thymic stromal dysplasia resulting in peripheral T-cell lymphopenia. In Foxn1:CFP-NTR transgenic mice, the bacterial nitroreductase enzyme is expressed in thymic epithelial cells and converts the prodrug CB1954 into a cytotoxic agent. This strategy enables titratable and durable destruction of thymopoietic tissue in early embryogenesis. Our results indicate that the resulting low levels of thymic capacity for T-cell production create a predisposition for the development of a complex autoimmune syndrome, chiefly characterized by inflammatory bowel disease and lymphocytic organ infiltrations. We conclude that the Foxn1:CFP-NTR transgenic mouse strain represents a suitable animal model to optimize established clinical protocols, such as thymus transplantation, to correct various forms of thymic dysplasia and to explore novel treatment options.
Topics: Anaplasia; Animals; Antineoplastic Agents; Apoptosis; Autoimmunity; Aziridines; Disease Models, Animal; Forkhead Transcription Factors; Humans; Inflammatory Bowel Diseases; Lymphopenia; Mice; Mice, Inbred C57BL; Mice, Transgenic; T-Lymphocytes; Thymus Gland
PubMed: 28992076
DOI: 10.1093/intimm/dxx048 -
Bioscience, Biotechnology, and... 2012Synthetic studies of Annonaceous acetogenins isolated from the plant family Annonaceae and marine natural products (miraziridine A, tokaramide A, and callipeltins)... (Review)
Review
Synthetic studies of Annonaceous acetogenins isolated from the plant family Annonaceae and marine natural products (miraziridine A, tokaramide A, and callipeltins) containing unusual amino acids, and recent studies of the structure-activity relationship of cysteine protease inhibitor are described.
Topics: Acetogenins; Animals; Annonaceae; Aziridines; Biological Products; Cysteine Proteinase Inhibitors; Molecular Structure; Oligopeptides; Peptides, Cyclic; Porifera; Structure-Activity Relationship
PubMed: 22785468
DOI: 10.1271/bbb.120176 -
Organic Letters May 2020Piperazines are prevalent in pharmaceuticals and natural products, but traditional methods do not typically introduce stereochemical complexity into the ring. To expand...
Piperazines are prevalent in pharmaceuticals and natural products, but traditional methods do not typically introduce stereochemical complexity into the ring. To expand access to these scaffolds, we report Rh-catalyzed ring expansions of aziridines and sulfonyl-1,2,3-triazoles to furnish dehydropiperazines with excellent diastereocontrol. Productive ring expansion proceeds via a pseudo-1,4-sigmatropic rearrangement of an aziridinium ylide species. However, the structural features of the carbene precursor are important, as pyridotriazoles undergo competing cheletropic extrusion to furnish ketimines.
Topics: Aziridines; Catalysis; Imines; Molecular Structure; Nitriles; Piperazines; Rhodium; Triazoles
PubMed: 32320259
DOI: 10.1021/acs.orglett.0c01124 -
Synapse (New York, N.Y.) Jun 2019Cancer survivorship has increased greatly as therapies have become more advanced and effective. Thus, we must now focus on improving the quality of life of patients...
Cancer survivorship has increased greatly as therapies have become more advanced and effective. Thus, we must now focus on improving the quality of life of patients after treatment. After chemotherapy, many patients experience chemotherapy-induced cognitive decline, indicating a need to investigate pathologies associated with this condition. In this study, we addressed cognitive impairment after thioTEPA treatment by assessing behavior and assaying cytokine production and the structure of dendrites in the hippocampus. Male mice were given three intraperitoneal injections of thioTEPA. Five weeks later, the mice underwent behavior testing, and brains were collected for Golgi staining and cytokine analysis. Behavior tests included y-maze and Morris water maze and licking behavioral task. Cytokines measured include: IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-5, IL-10, IL-12p70, MCP-1, TNF-α, GMCSF, and RANTES. We observed decreased memory retention in behavioral tasks. Also, dendritic arborization and length were decreased after chemotherapy treatment. Finally, thioTEPA decreased cytokine production in animals treated with chemotherapy, compared to saline-treated controls. Here, we used a mouse model to correlate the decreases in dendritic complexity and inflammatory cytokine production with cognitive impairment after chemotherapy.
Topics: Animals; Antineoplastic Agents, Alkylating; Brain; Cognition; Cognitive Dysfunction; Cytokines; Injections, Intraperitoneal; Male; Maze Learning; Mice; Mice, Inbred C57BL; Movement; Thiotepa
PubMed: 30586195
DOI: 10.1002/syn.22085 -
Expert Opinion on Drug Metabolism &... Jul 2017Apaziquone (also known as EO9 and Qapzola) is a prodrug that is activated to DNA damaging species by oxidoreductases (particularly NQO1) and has the ability to kill... (Review)
Review
Apaziquone (also known as EO9 and Qapzola) is a prodrug that is activated to DNA damaging species by oxidoreductases (particularly NQO1) and has the ability to kill aerobic and/or hypoxic cancer cells. Areas covered: Whilst its poor pharmacokinetic properties contributed to its failure in phase II clinical trials when administered intravenously, these properties were ideal for loco-regional therapies. Apaziquone demonstrated good anti-cancer activity against non-muscle invasive bladder cancer (NMIBC) when administered intravesically to marker lesions and was well tolerated with no systemic side effects. However, phase III clinical trials did not reach statistical significance for the primary endpoint of 2-year recurrence in apaziquone over placebo although improvements were observed. Post-hoc analysis of the combined study data did indicate a significant benefit for patients treated with apaziquone, especially when the instillation of apaziquone was given 30 min or more after surgery. A further phase III study is ongoing to test the hypotheses generated in the unsuccessful phase III studies conducted to date. Expert opinion: Because of its specific pharmacological properties, Apaziquone is excellently suited for local therapy such as NMIBC. Future studies should include proper biomarkers.
Topics: Administration, Intravesical; Animals; Antineoplastic Agents; Aziridines; Humans; Indolequinones; Neoplasm Invasiveness; Neoplasm Recurrence, Local; Urinary Bladder Neoplasms
PubMed: 28637373
DOI: 10.1080/17425255.2017.1341490 -
Transplantation and Cellular Therapy Mar 2023Allogenic hematopoietic cell transplantation (HCT) is the best curative approach for patients with severe aplastic anemia (SAA). The outcomes of HCT from haploidentical...
Impact of Conditioning Regimen and Graft-versus-Host Disease Prophylaxis on The Outcome of Haploidentical Peripheral Blood Stem Cell Transplantation for High-Risk Severe Aplastic Anemia in Children and Young Adults: A Report from the Pediatric Severe Aplastic Anemia Consortium of India.
Allogenic hematopoietic cell transplantation (HCT) is the best curative approach for patients with severe aplastic anemia (SAA). The outcomes of HCT from haploidentical family donors (HFDs) have improved, making it a feasible option for patients lacking an HLA-identical donor. However, data on HFD-HCT for younger patients with SAA is sparse. In this multicenter retrospective study, we evaluated the outcomes of 79 patients undergoing HFD-HCT for SAA. All the patients were heavily pretransfused, the median time to HCT was >12 months, and 67% had failed previous therapies. Conditioning was based on fludarabine (Flu)-cyclophosphamide (Cy)-antithymocyte globulin (ATG)/total body irradiation (TBI) with or without thiotepa/melphalan (TT/Mel). Post-transplantation Cy (PTCy) and calcineurin inhibitors (CNIs)/sirolimus were used as graft-versus-host disease (GVHD) prophylaxis with or without abatacept. The rate of primary graft failure (PGF) was 16.43% overall, lower in patients conditioned with TT/Mel. The incidences of acute and chronic GVHD were 26.4% and 18.9%, respectively. At a median follow-up of 48 months, the overall survival (OS) and event-free survival (EFS) were 61.6% and 58.1%, respectively. Both OS and EFS were better in the TT/Mel recipients and with abatacept as GVHD prophylaxis. On multivariate analysis, the use of abatacept was found to favorably impact the outcome variables, including GVHD and EFS. Our study suggests that PTCy-based HFD-HCT is a reasonable option for young patients with high-risk SAA, in whom optimization of conditioning and GVHD prophylaxis might further improve outcomes.
Topics: Humans; Child; Young Adult; Peripheral Blood Stem Cell Transplantation; Anemia, Aplastic; Abatacept; Retrospective Studies; Cyclophosphamide; Graft vs Host Disease; Thiotepa
PubMed: 36572385
DOI: 10.1016/j.jtct.2022.12.010 -
Dalton Transactions (Cambridge, England... May 2012The synthesis, spectroscopic and X-ray structural characterization of copper(II) and palladium(II) complexes with aziridine ligands as 2-dimethylaziridine HNCH(2)CMe(2)...
The synthesis, spectroscopic and X-ray structural characterization of copper(II) and palladium(II) complexes with aziridine ligands as 2-dimethylaziridine HNCH(2)CMe(2) (a), the bidentate N-(2-aminoethyl)aziridines C(2)H(4)NC(2)H(4)NH(2) (b) or CH(2)CMe(2)NCH(2)CMe(2)NH(2) (c) as well as the unsaturated azirine NCH(2)CPh (d) are reported. Cleavage of the cyclometallated Pd(II) dimer [μ-Cl(C(6)H(4)CHMeNMe(2)-C,N)Pd](2) with ligand a yielded compound [Cl(NHCH(2)CMe(2))(C(6)H(4)CHMe(2)NMe(2)-C,N)Pd] (1a). The reaction of the aziridine complex trans-[Cl(2)Pd(HNC(2)H(4))(2)] with an excess of aziridine in the presence of AgOTf gave the ionic chelate complex trans-[(C(2)H(4)NC(2)H(4)NH(2)-N,N')(2)Pd](OTf)(2) (2b) which contains the new ligand b formed by an unexpected insertion and ring opening reaction of two aziridines ("aziridine dimerization"). CuCl(2) reacted in pure HNC(2)H(4) or HNCH(2)CMe(2) (b) again by "dimerization" to give the tris-chelated ionic complex [Cu(C(2)H(4)NC(2)H(4)NH(2)-N,N')(3)]Cl(2) (3b) or the bis-chelated complex [CuCl(C(2)H(2)Me(2)NC(2)H(2)Me(2)NH(2)-N,N')(2)]Cl (4c). By addition of 2H-3-phenylazirine (d) to PdCl(2), trans-[Cl(2)Pd(NCH(2)CPh)(2)] (5d) was formed. All new compounds were characterized by NMR, IR and mass spectra and also by X-ray structure analyses (except 3b). Additionally the cytotoxic effects of these complexes were examined on HL-60 and NALM-6 human leukemia cells and melanoma WM-115 cells. The antimicrobial activity was also determined. The growth of Gram-positive bacterial strains (S. aureus, S. epidermidis, E. faecalis) was inhibited by almost all tested complexes at the concentrations of 37.5-300.0 μg mL(-1). However, MIC values of complexes obtained for Gram-negative E. coli and P. aeruginosa, as well as for C. albicans yeast, mostly exceeded 300 μg mL(-1). The highest antibacterial activity was achieved by complexes 1a and 2b. Complex 2b also inhibited the growth of Gram-negative bacteria.
Topics: Anti-Infective Agents; Antineoplastic Agents; Aziridines; Bacteria; Candida albicans; Cell Line, Tumor; Chemistry Techniques, Synthetic; Copper; Dimerization; Humans; Inhibitory Concentration 50; Microbial Sensitivity Tests; Organometallic Compounds; Palladium
PubMed: 22466757
DOI: 10.1039/c2dt12107g -
Journal of Natural Medicines Jan 2024Epoxides, aziridines, and cyclopropanes are found in various medicinal natural products, including polyketides, terpenes, peptides, and alkaloids. Many classes of... (Review)
Review
Epoxides, aziridines, and cyclopropanes are found in various medicinal natural products, including polyketides, terpenes, peptides, and alkaloids. Many classes of biosynthetic enzymes are involved in constructing these ring structures during their biosynthesis. This review summarizes our current knowledge regarding how α-ketoglutarate-dependent nonheme iron enzymes catalyze the formation of epoxides, aziridines, and cyclopropanes in nature, with a focus on enzyme mechanisms.
Topics: Iron; Ketoglutaric Acids; Catalysis; Cyclopropanes; Aziridines; Epoxy Compounds
PubMed: 37980694
DOI: 10.1007/s11418-023-01760-4 -
Chemistry (Weinheim An Der Bergstrasse,... Dec 2018Cyclophellitol aziridines are potent irreversible inhibitors of retaining glycosidases and versatile intermediates in the synthesis of activity-based glycosidase probes...
Cyclophellitol aziridines are potent irreversible inhibitors of retaining glycosidases and versatile intermediates in the synthesis of activity-based glycosidase probes (ABPs). Direct 3-amino-2-(trifluoromethyl)quinazolin-4(3H)-one-mediated aziridination of l-ido-configured cyclohexene has enabled the synthesis of new covalent inhibitors and ABPs of α-l-iduronidase, deficiency of which underlies the lysosomal storage disorder mucopolysaccharidosis type I (MPS I). The iduronidase ABPs react covalently and irreversibly in an activity-based manner with human recombinant α-l-iduronidase (rIDUA, Aldurazyme ). The structures of IDUA when complexed with the inhibitors in a non-covalent transition state mimicking form and a covalent enzyme-bound form provide insights into its conformational itinerary. Inhibitors 1-3 adopt a half-chair conformation in solution ( H and H ), as predicted by DFT calculations, which is different from the conformation of the Michaelis complex observed by crystallographic studies. Consequently, 1-3 may need to overcome an energy barrier in order to switch from the H conformation to the transition state ( B) binding conformation before reacting and adopting a covalent S conformation. rIDUA can be labeled with fluorescent Cy5 ABP 2, which allows monitoring of the delivery of therapeutic recombinant enzyme to lysosomes, as is intended in enzyme replacement therapy for the treatment of MPS I patients.
Topics: Aziridines; Chromatography, Liquid; Cyclohexanols; Enzyme Assays; Enzyme Inhibitors; Fluorescent Dyes; Humans; Iduronidase; Microscopy, Fluorescence; Models, Molecular; Recombinant Proteins; Staining and Labeling; Tandem Mass Spectrometry
PubMed: 30307091
DOI: 10.1002/chem.201804662 -
Journal of the American Chemical Society Nov 2022Aziridines are readily available C(sp) precursors that afford valuable β-functionalized amines upon ring opening. In this article, we report a Ni/photoredox methodology...
Aziridines are readily available C(sp) precursors that afford valuable β-functionalized amines upon ring opening. In this article, we report a Ni/photoredox methodology for C(sp)-C(sp) cross-coupling between aziridines and methyl/1°/2° aliphatic alcohols activated as benzaldehyde dialkyl acetals. Orthogonal activation modes of each alkyl coupling partner facilitate cross-selectivity in the C(sp)-C(sp) bond-forming reaction: the benzaldehyde dialkyl acetal is activated via hydrogen atom abstraction and β-scission via a bromine radical (generated in situ from single-electron oxidation of bromide), whereas the aziridine is activated at the Ni center via reduction. We demonstrate that an Ni(II) azametallacycle, conventionally proposed in aziridine cross-coupling, is not an intermediate in the productive cross-coupling. Rather, stoichiometric organometallic and linear free energy relationship studies indicate that aziridine activation proceeds via Ni(I) oxidative addition, a previously unexplored elementary step.
Topics: Acetals; Catalysis; Benzaldehydes; Nickel; Aziridines
PubMed: 36256882
DOI: 10.1021/jacs.2c09294