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1.
Exp Cell Res ; 442(1): 114196, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-39117090

ABSTRACT

Reproduction by egg-laying (oviparity) or live-bearing (viviparity) is a genetically determined trait fundamental to the biology of amniotes. Squamates are an emerging model for the genetics of reproductive mode yet lack cell culture models valuable for exploring molecular mechanisms. Here, we report a novel primary culture model for reproductive biology: cell cultures derived from the oviduct tissues (infundibulum, uterus and vagina) of oviparous and viviparous common lizards (Lacertidae: Zootoca vivipara). We maintained and expanded these cultures for over 100 days, including repeated subculturing and successful revival of cryopreserved cells. Immunocytochemical investigation suggested expression of both epithelial and fibroblast-like proteins, and RNA sequencing of cultured cells as compared to in vivo oviduct tissue showed changes in gene expression in response to the cell culture environment. Despite this, we confirmed the maintenance of distinct gene expression patterns in viviparous and oviparous cells after 60+ days of cell culture, finding 354 differentially expressed genes between viviparous and oviparous cells. Furthermore, we confirmed the expression of 15 viviparity-associated candidate genes in cells maintained for 60+ days in culture. Our study demonstrates the feasibility and utility of oviduct cell culture for molecular analysis of reproductive mode and provides a tool for future genetic experiments.


Subject(s)
Lizards , Oviducts , Oviparity , Viviparity, Nonmammalian , Animals , Female , Lizards/genetics , Lizards/physiology , Oviducts/cytology , Oviducts/metabolism , Viviparity, Nonmammalian/genetics , Oviparity/genetics , Cells, Cultured , Primary Cell Culture/methods
2.
BMC Vet Res ; 20(1): 236, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38824607

ABSTRACT

BACKGROUND: The chicken's inflammatory response is an essential part of the bird's response to infection. A single dose of Escherichia coli (E. coli) lipopolysaccharide (LPS) endotoxin can activate the acute phase response (APR) and lead to the production of acute phase proteins (APPs). In this study, the responses of established chicken APPs, Serum amyloid A (SAA) and Alpha-1-acid-glycoprotein (AGP), were compared to two novel APPs, Hemopexin (Hpx) and Extracellular fatty acid binding protein (Ex-FABP), in 15-day old broilers over a time course of 48Ā h post E.coli LPS challenge. We aimed to investigate and validate their role as biomarkers of an APR. Novel plant extracts, Citrus (CTS) and cucumber (CMB), were used as dietary supplements to investigate their ability to reduce the inflammatory response initiated by the endotoxin. RESULTS: A significant increase of established (SAA, AGP) and novel (Ex-FABP, Hpx) APPs was detected post E.coli LPS challenge. Extracellular fatty acid binding protein (Ex-FABP) showed a similar early response to SAA post LPS challenge by increasing ~ 20-fold at 12Ā h post challenge (P < 0.001). Hemopexin (Hpx) showed a later response by increasing Ć¢ĀˆĀ¼5-fold at 24Ā h post challenge (P < 0.001) with a similar trend to AGP. No differences in APP responses were identified between diets (CTS and CMB) using any of the established or novel biomarkers. CONCLUSIONS: Hpx and Ex-FABP were confirmed as potential biomarkers of APR in broilers when using an E. coli LPS model along with SAA and AGP. However, no clear advantage for using either of dietary supplements to modulate the APR was identified at the dosage used.


Subject(s)
Acute-Phase Proteins , Acute-Phase Reaction , Biomarkers , Chickens , Escherichia coli , Lipopolysaccharides , Animals , Biomarkers/blood , Lipopolysaccharides/pharmacology , Acute-Phase Proteins/metabolism , Acute-Phase Proteins/analysis , Endotoxins , Serum Amyloid A Protein/analysis , Serum Amyloid A Protein/metabolism , Orosomucoid/metabolism , Dietary Supplements , Plant Extracts/pharmacology , Fatty Acid-Binding Proteins/metabolism , Poultry Diseases/microbiology , Hemopexin/metabolism
3.
Rapid Commun Mass Spectrom ; 37(10): e9497, 2023 May 30.
Article in English | MEDLINE | ID: mdl-36851885

ABSTRACT

RATIONALE: The study of protein synthesis in farm animals is uncommon despite its potential to increase knowledge about metabolism and discover new biomarkers of health and growth status. The present study describes a novel dynamic proteomics approach for the measurement of protein fractional synthesis rate (FSR) in broiler chickens. METHODS: Chickens received a 10Ā g/kg oral dose of 2 H2 O at day 21 of their life. Body water 2 H abundance was measured in plasma samples using a portable Fourier transform infrared spectrometer. Free and protein-bound amino acids (AAs) were isolated and had their 2 H enrichment measured by gas chromatography with mass spectrometry (GC/MS). Peptide 2 H enrichment was measured by proteomics analysis of plasma and muscle samples. Albumin, fibrinogen and muscle protein FSR were calculated from GC/MS and proteomics data. RESULTS: Ala appeared to be more enriched at the site of protein synthesis than in the AA free pools. Glu was found to be the AA closest to isotopic equilibrium between the different AA pools. Glu was used as an anchor to calculate n(AA) values necessary for chicken protein FSR calculation in dynamic proteomics studies. FSR values calculated using proteomics data and GC/MS data showed good agreement as evidenced by a Bland-Altman residual plot. CONCLUSIONS: A new dynamic proteomics approach for the measurement of broiler chicken individual protein FSR based on the administration of a single 2 H2 O oral bolus has been developed and validated. The proposed approach could facilitate new immunological and nutritional studies on free-living animals.


Subject(s)
Chickens , Proteomics , Animals , Gas Chromatography-Mass Spectrometry/methods , Muscles/metabolism , Peptides/metabolism
4.
Lancet Oncol ; 23(12): 1508-1516, 2022 12.
Article in English | MEDLINE | ID: mdl-36400098

ABSTRACT

BACKGROUND: Stereotactic ablative body radiotherapy (SABR) is a non-invasive treatment option for primary renal cell carcinoma, for which long-term data are awaited. The primary aim of this study was to report on long-term efficacy and safety of SABR for localised renal cell carcinoma. METHODS: This study was an individual patient data meta-analysis, for which patients undergoing SABR for primary renal cell carcinoma across 12 institutions in five countries (Australia, Canada, Germany, Japan, and the USA) were eligible. Eligible patients had at least 2 years of follow-up, were aged 18 years or older, had any performance status, and had no previous local therapy. Patients with metastatic renal cell carcinoma or upper-tract urothelial carcinoma were excluded. SABR was delivered as a single or multiple fractions of greater than 5 Gy. The primary endpoint was investigator-assessed local failure per the Response Evaluation Criteria in Solid Tumours version 1.1, and was evaluated using cumulative incidence functions. FINDINGS: 190 patients received SABR between March 23, 2007, and Sept 20, 2018. Single-fraction SABR was delivered in 81 (43%) patients and multifraction SABR was delivered in 109 (57%) patients. Median follow-up was 5Ā·0 years (IQR 3Ā·4-6Ā·8). 139 (73%) patients were men, and 51 (27%) were women. Median age was 73Ā·6 years (IQR 66Ā·2-82Ā·0). Median tumour diameter was 4Ā·0 cm (IQR 2Ā·8-4Ā·9). 96 (75%) of 128 patients with available operability details were deemed inoperable by the referring urologist. 56 (29%) of 190 patients had a solitary kidney. Median baseline estimated glomerular filtration rate (eGFR) was 60Ā·0 mL/min per 1Ā·73 m2 (IQR 42Ā·0-76Ā·0) and decreased by 14Ā·2 mL/min per 1Ā·73 m2 (IQR 5Ā·4-22Ā·5) by 5 years post-SABR. Seven (4%) patients required dialysis post-SABR. The cumulative incidence of local failure at 5 years was 5Ā·5% (95% CI 2Ā·8-9Ā·5) overall, with single-fraction SABR yielding fewer local failures than multifraction (Gray's p=0Ā·020). There were no grade 3 toxic effects or treatment-related deaths. One (1%) patient developed an acute grade 4 duodenal ulcer and late grade 4 gastritis. INTERPRETATION: SABR is effective and safe in the long term for patients with primary renal cell carcinoma. Single-fraction SABR might yield less local failure than multifraction, but further evidence from randomised trials is needed to elucidate optimal treatment schedules. These mature data lend further support for renal SABR as a treatment option for patients unwilling or unfit to undergo surgery. FUNDING: None.


Subject(s)
Carcinoma, Renal Cell , Carcinoma, Transitional Cell , Kidney Neoplasms , Radiosurgery , Urinary Bladder Neoplasms , Male , Humans , Female , Aged , Carcinoma, Renal Cell/radiotherapy , Carcinoma, Renal Cell/surgery , Radiosurgery/adverse effects , Kidney Neoplasms/radiotherapy , Kidney Neoplasms/surgery , Kidney
5.
Chemistry ; 28(48): e202201107, 2022 Aug 26.
Article in English | MEDLINE | ID: mdl-35642626

ABSTRACT

A range of highly functionalized polycyclic fragments have been synthesized, employing a catalytic dehydrative cyclization. A range of nucleophiles are shown to be successful, with the reaction producing numerous high value motifs.


Subject(s)
Cyclization , Catalysis
6.
Org Biomol Chem ; 20(42): 8209-8211, 2022 Nov 02.
Article in English | MEDLINE | ID: mdl-36239212

ABSTRACT

Herein, we report the development of a novel route to tricyclic lactam products via a facile aza-[4 + 2] cycloaddition of catalytically generated acyliminium ions. Employing a Ca(NTf2)2/nBu4NPF6 catalyst system in low loadings, a range of diverse fused ring systems can be synthesised in predominantly good yields.


Subject(s)
Cycloaddition Reaction , Catalysis , Ions
7.
Int J Mol Sci ; 23(3)2022 Jan 21.
Article in English | MEDLINE | ID: mdl-35163083

ABSTRACT

In the past two decades, extensive efforts have been made to develop agents targeting prostate-specific membrane antigen (PSMA) for prostate cancer imaging and therapy. To date, represented by two recent approvals of [68Ga]Ga-PSMA-11 and [18F]F-DCFPyL by the United States Food and Drug Administration (US-FDA) for positron emission tomography (PET) imaging to identify suspected metastases or recurrence in patients with prostate cancer, PSMA-targeting imaging and theranostic agents derived from small molecule PSMA inhibitors have advanced to clinical practice and trials of prostate cancer. The focus of current development of new PSMA-targeting agents has thus shifted to the improvement of in vivo pharmacokinetics and higher specific binding affinity with the aims to further increase the detection sensitivity and specificity and minimize the toxicity to non-target tissues, particularly the kidneys. The main strategies involve systematic chemical modifications of the linkage between the targeting moiety and imaging/therapy payloads. In addition to a summary of the development history of PSMA-targeting agents, this review provides an overview of current advances and future promise of PSMA-targeted imaging and theranostics with focuses on the structural determinants of the chemical modification towards the next generation of PSMA-targeting agents.


Subject(s)
Antigens, Surface/metabolism , Glutamate Carboxypeptidase II/antagonists & inhibitors , Glutamate Carboxypeptidase II/metabolism , Positron-Emission Tomography/methods , Prostatic Neoplasms/diagnostic imaging , Prostatic Neoplasms/radiotherapy , Radiopharmaceuticals/therapeutic use , Humans , Male , Precision Medicine , Prostatic Neoplasms/pathology , Radiopharmaceuticals/metabolism
8.
J Neurochem ; 158(2): 217-232, 2021 07.
Article in English | MEDLINE | ID: mdl-33864399

ABSTRACT

Gangliosides are expressed on plasma membranes throughout the body and enriched in the nervous system. A critical role for complex a- and b-series gangliosides in central and peripheral nervous system ageing has been established through transgenic manipulation of enzymes in ganglioside biosynthesis. Disrupting GalNAc-transferase (GalNAc-T), thus eliminating all a- and b-series complex gangliosides (with consequent over-expression of GM3 and GD3) leads to an age-dependent neurodegeneration. Mice that express only GM3 ganglioside (double knockout produced by crossing GalNAc-T-/- and GD3 synthase-/- mice, Dbl KO) display markedly accelerated neurodegeneration with reduced survival. Degenerating axons and disrupted node of Ranvier architecture are key features of complex ganglioside-deficient mice. Previously, we have shown that reintroduction of both a- and b-series gangliosides into neurons on a global GalNAcT-/- background is sufficient to rescue this age-dependent neurodegenerative phenotype. To determine the relative roles of a- and b-series gangliosides in this rescue paradigm, we herein reintroduced GalNAc-T into neurons of Dbl KO mice, thereby reconstituting a-series but not b-series complex gangliosides. We assessed survival, axon degeneration, axo-glial integrity, inflammatory markers and lipid-raft formation in these Rescue mice compared to wild-type and Dbl KO mice. We found that this neuronal reconstitution of a-series complex gangliosides abrogated the adult lethal phenotype in Dbl KO mice, and partially attenuated the neurodegenerative features. This suggests that whilst neuronal expression of a-series gangliosides is critical for survival during ageing, it is not entirely sufficient to restore complete nervous system integrity in the absence of either b-series or glial a-series gangliosides.


Subject(s)
G(M3) Ganglioside/metabolism , Gangliosides/metabolism , Genes, Lethal/genetics , Neurons/metabolism , Animals , Axons/pathology , Heredodegenerative Disorders, Nervous System/genetics , Heredodegenerative Disorders, Nervous System/pathology , Inflammation/metabolism , Membrane Microdomains/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , N-Acetylgalactosaminyltransferases/genetics , Phenotype , Ranvier's Nodes/pathology , Sialyltransferases/genetics , Survival Analysis , Polypeptide N-acetylgalactosaminyltransferase
9.
Brain ; 143(5): 1383-1399, 2020 05 01.
Article in English | MEDLINE | ID: mdl-32419025

ABSTRACT

Pelizaeus-Merzbacher disease is a fatal X-linked leukodystrophy caused by mutations in the PLP1 gene, which is expressed in the CNS by oligodendrocytes. Disease onset, symptoms and mortality span a broad spectrum depending on the nature of the mutation and thus the degree of CNS hypomyelination. In the absence of an effective treatment, direct cell transplantation into the CNS to restore myelin has been tested in animal models of severe forms of the disease with failure of developmental myelination, and more recently, in severely affected patients with early disease onset due to point mutations in the PLP1 gene, and absence of myelin by MRI. In patients with a PLP1 duplication mutation, the most common cause of Pelizaeus-Merzbacher disease, the pathology is poorly defined because of a paucity of autopsy material. To address this, we examined two elderly patients with duplication of PLP1 in whom the overall syndrome, including end-stage pathology, indicated a complex disease involving dysmyelination, demyelination and axonal degeneration. Using the corresponding Plp1 transgenic mouse model, we then tested the capacity of transplanted neural stem cells to restore myelin in the context of PLP overexpression. Although developmental myelination and axonal coverage by endogenous oligodendrocytes was extensive, as assessed using electron microscopy (n = 3 at each of four end points) and immunostaining (n = 3 at each of four end points), wild-type neural precursors, transplanted into the brains of the newborn mutants, were able to effectively compete and replace the defective myelin (n = 2 at each of four end points). These data demonstrate the potential of neural stem cell therapies to restore normal myelination and protect axons in patients with PLP1 gene duplication mutation and further, provide proof of principle for the benefits of stem cell transplantation for other fatal leukodystrophies with 'normal' developmental myelination.


Subject(s)
Brain/pathology , Disease Models, Animal , Neural Stem Cells/transplantation , Pelizaeus-Merzbacher Disease/pathology , Animals , Humans , Male , Mice, Transgenic , Mutation , Myelin Proteolipid Protein/genetics , Myelin Sheath/pathology , Pelizaeus-Merzbacher Disease/genetics
10.
Int J Mol Sci ; 22(21)2021 Oct 28.
Article in English | MEDLINE | ID: mdl-34769107

ABSTRACT

Herniation of the intervertebral disc (IVDH) is the most common cause of neurological and intervertebral disc degeneration-related diseases. Since the disc starts to degenerate before it can be observed by currently available diagnostic methods, there is an urgent need for novel diagnostic approaches. To identify molecular networks and pathways which may play important roles in intervertebral disc herniation, as well as to reveal the potential features which could be useful for monitoring disease progression and prognosis, multi-omics profiling, including high-resolution liquid chromatography-mass spectrometry (LC-MS)-based metabolomics and tandem mass tag (TMT)-based proteomics was performed. Cerebrospinal fluid of nine dogs with IVDH and six healthy controls were used for the analyses, and an additional five IVDH samples were used for proteomic data validation. Furthermore, multi-omics data were integrated to decipher a complex interaction between individual omics layers, leading to an improved prediction model. Together with metabolic pathways related to amino acids and lipid metabolism and coagulation cascades, our integromics prediction model identified the key features in IVDH, namely the proteins follistatin Like 1 (FSTL1), secretogranin V (SCG5), nucleobindin 1 (NUCB1), calcitonin re-ceptor-stimulating peptide 2 precursor (CRSP2) and the metabolites N-acetyl-D-glucosamine and adenine, involved in neuropathic pain, myelination, and neurotransmission and inflammatory response, respectively. Their clinical application is to be further investigated. The utilization of a novel integrative interdisciplinary approach may provide new opportunities to apply innovative diagnostic and monitoring methods as well as improve treatment strategies and personalized care for patients with degenerative spinal disorders.


Subject(s)
Dog Diseases/cerebrospinal fluid , Intervertebral Disc Displacement/veterinary , Animals , Case-Control Studies , Dogs , Intervertebral Disc Displacement/cerebrospinal fluid , Metabolome , Proteome , Proteomics
11.
J Neurosci ; 39(1): 63-77, 2019 01 02.
Article in English | MEDLINE | ID: mdl-30446529

ABSTRACT

Sulfatides and gangliosides are raft-associated glycolipids essential for maintaining myelinated nerve integrity. Mice deficient in sulfatide (cerebroside sulfotransferase knock-out, CST-/-) or complex gangliosides (Ɵ-1,4-N-acetylegalactosaminyltransferase1 knock-out, GalNAc-T-/-) display prominent disorganization of proteins at the node of Ranvier (NoR) in early life and age-dependent neurodegeneration. Loss of neuronal rather than glial complex gangliosides underpins the GalNAc-T-/- phenotype, as shown by neuron- or glial-specific rescue, whereas sulfatide is principally expressed and functional in glial membranes. The similarities in NoR phenotype of CST-/-, GalNAc-T-/-, and axo-glial protein-deficient mice suggests that these glycolipids stabilize membrane proteins including neurofascin155 (NF155) and myelin-associated glycoprotein (MAG) at axo-glial junctions. To assess the functional interactions between sulfatide and gangliosides, CST-/- and GalNAc-T-/- genotypes were interbred. CST-/-Ɨ GalNAc-T-/- mice develop normally to postnatal day 10 (P10), but all die between P20 and P25, coinciding with peak myelination. Ultrastructural, immunohistological, and biochemical analysis of either sex revealed widespread axonal degeneration and disruption to the axo-glial junction at the NoR. In addition to sulfatide-dependent loss of NF155, CST-/- Ɨ GalNAc-T-/- mice exhibited a major reduction in MAG protein levels in CNS myelin compared with WT and single-lipid-deficient mice. The CST-/- Ɨ GalNAc-T-/- phenotype was fully restored to that of CST-/- mice by neuron-specific expression of complex gangliosides, but not by their glial-specific expression nor by the global expression of a-series gangliosides. These data indicate that sulfatide and complex b-series gangliosides on the glial and neuronal membranes, respectively, act in concert to promote NF155 and MAG in maintaining the stable axo-glial interactions essential for normal nerve function.SIGNIFICANCE STATEMENT Sulfatides and complex gangliosides are membrane glycolipids with important roles in maintaining nervous system integrity. Node of Ranvier maintenance in particular requires stable compartmentalization of multiple membrane proteins. The axo-glial adhesion molecules neurofascin155 (NF155) and myelin-associated glycoprotein (MAG) require membrane microdomains containing either sulfatides or complex gangliosides to localize and function effectively. The cooperative roles of these microdomains and associated proteins are unknown. Here, we show vital interdependent roles for sulfatides and complex gangliosides because double (but not single) deficiency causes a rapidly lethal phenotype at an early age. These findings suggest that sulfatides and complex gangliosides on opposing axo-glial membranes are responsible for essential tethering of the axo-glial junction proteins NF155 and MAG, which interact to maintain the nodal complex.


Subject(s)
Axons/physiology , Gangliosides/metabolism , Gangliosides/physiology , Myelin Sheath/physiology , Neuroglia/physiology , Neurons/physiology , Sulfoglycosphingolipids/metabolism , Animals , Cell Adhesion Molecules/genetics , Female , Genotype , Life Expectancy , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Myelin-Associated Glycoprotein/genetics , Myelin-Associated Glycoprotein/physiology , N-Acetylgalactosaminyltransferases/genetics , Nerve Growth Factors/genetics , Neuroglia/metabolism , Neurons/metabolism , Ranvier's Nodes/physiology , Sulfotransferases/genetics , Sulfotransferases/physiology
12.
Chemistry ; 26(62): 14118-14123, 2020 Nov 06.
Article in English | MEDLINE | ID: mdl-32710473

ABSTRACT

A 5-step enantioselective synthesis of the potent anti-HIV nucleoside islatravir is reported. The highly efficient route was enabled by a novel enantioselective alkynylation of an α,Ɵ-unsaturated ketone, a unique ozonolysis-dealkylation cascade in water, and an enzymatic aldol-glycosylation cascade.

13.
Mol Pharm ; 17(11): 4180-4188, 2020 11 02.
Article in English | MEDLINE | ID: mdl-32960613

ABSTRACT

Targeted α particle therapy (TAT) is ideal for treating disease while minimizing damage to surrounding nontargeted tissues due to short path length and high linear energy transfer (LET). We developed a TAT for metastatic uveal melanoma, targeting the melanocortin-1 receptor (MC1R), which is expressed in 94% of uveal melanomas. Two versions of the therapy are being investigated: 225Ac-DOTA-Ahx-MC1RL (225Ac-Ahx) and 225Ac-DOTA-di-d-Glu-MC1RL (225Ac-di-d-Glu). The biodistribution (BD) from each was studied and a multicompartment pharmacokinetic (PK) model was developed to describe drug distribution rates. Two groups of 16 severe combined immunodeficient (SCID) mice bearing high MC1R expressing tumors were intravenously injected with 225Ac-Ahx or 225Ac-di-d-Glu. After injection, four groups (n = 4) were euthanized at 24, 96, 144, and 288 h time points for each cohort. Tumors and 13 other organs were harvested at each time point. Isomeric ƎĀ³ spectra were measured in tissue samples using a scintillation ƎĀ³ detector and converted to α activity using factors for ƎĀ³ ray abundance per α decay. Time activity curves were calculated for each organ. A five-compartment PK model was built with the following compartments: blood, tumor, normal tissue, kidney, and liver. This model is characterized by a system of five ordinary differential equations using mass action kinetics, which describe uptake, intercompartmental transitions, and clearance rates. The ordinary differential equations were simultaneously solved and fit to experimental data using a genetic algorithm for optimization. The BD data show that both compounds have minimal distribution to organs at risk other than the kidney and liver. The PK parameter estimates had less than 5% error. From these data, 225Ac-Ahx showed larger and faster uptake in the liver. Both compounds had comparable uptake and clearance rates for other compartments. The BD and PK behavior for two targeted radiopharmaceuticals were investigated. The PK model fit the experimental data and provided insight into the kinetics of the compounds systematically.


Subject(s)
Alpha Particles/therapeutic use , Melanoma, Experimental/drug therapy , Melanoma/drug therapy , Radiopharmaceuticals/administration & dosage , Radiopharmaceuticals/pharmacokinetics , Uveal Neoplasms/drug therapy , alpha-MSH/administration & dosage , alpha-MSH/pharmacokinetics , Animals , Cell Line, Tumor , Ligands , Melanoma/metabolism , Melanoma/pathology , Melanoma, Experimental/metabolism , Melanoma, Experimental/pathology , Metabolic Clearance Rate , Mice , Mice, Inbred BALB C , Mice, SCID , Molecular Targeted Therapy/methods , Receptor, Melanocortin, Type 1/metabolism , Tissue Distribution , Treatment Outcome , Tumor Burden/drug effects , Uveal Neoplasms/metabolism , Uveal Neoplasms/pathology , Xenograft Model Antitumor Assays
14.
J Org Chem ; 85(2): 301-305, 2020 Jan 17.
Article in English | MEDLINE | ID: mdl-31775003

ABSTRACT

A mild and facile Peterson olefination has been developed employing low catalyst loading of the BrĆønsted acid HNTf2. The reactions are typically performed at room temperature, with the reaction tolerant to a range of useful functionalities. Furthermore, we have extended this methodology to the synthesis of enynes.

15.
J Org Chem ; 85(8): 5615-5628, 2020 04 17.
Article in English | MEDLINE | ID: mdl-32208694

ABSTRACT

Herein we report our full investigation into the calcium catalyzed generation and trapping of N-acyliminium ions from readily available 3-hydroxyisoindolinones. We have successfully employed a range of traditional nucleophiles including carbon, nitrogen, and sulfur containing reactive partners. The reaction is tolerant to a wide range of functionalities and provides high value scaffolds in good to excellent yields.

16.
Eur J Neurosci ; 50(12): 3896-3905, 2019 12.
Article in English | MEDLINE | ID: mdl-31336405

ABSTRACT

Canine degenerative myelopathy (DM) is a progressive neurological disorder that may be considered to be a large animal model for specific forms of the fatal human disease, familial amyotrophic lateral sclerosis (fALS). DM is associated with a c118G>A mutation of the superoxide dismutase 1 (Sod1) gene, and a significant proportion of cases are inherited in an autosomal recessive manner in contrast to the largely, but not exclusively, dominant mode of inheritance in fALS. The consensus view is that these Sod1/SOD1 mutations result in a toxic gain of function but the mechanisms remain unclear. Here we used an in vitro neuroblastoma cell line transfection system to monitor wild-type and mutant forms of SOD1 fusion proteins containing either a Cherry or an enhanced green fluorescent protein (EGFP) tag. These fusion proteins retained SOD1 enzymatic activity on a native gel assay system. We demonstrate that SOD1 aggregate density is significantly higher in DM transfectants compared to wild-type. In addition, we show by co-immunoprecipitation and confocal microscopy, evidence for a potential interaction between wild-type and mutant forms of SOD1 in co-transfected cells. While in vitro studies have shown SOD1 heterodimer formation in fALS models, this is the first report for DM SOD1. Therefore, despite for the majority of cases there is a difference in the mode of inheritance between fALS and DM, a similar interaction between wild-type and mutant SOD1 forms can occur. Clarifying the role of SOD1 in DM may also be of benefit to understanding the role of SOD1 in fALS.


Subject(s)
Amyotrophic Lateral Sclerosis/genetics , Mutation/genetics , Superoxide Dismutase-1/genetics , Superoxide Dismutase/genetics , Animals , Cell Line , Disease Models, Animal , Dogs , Green Fluorescent Proteins/genetics , Humans , Spinal Cord Diseases/genetics
17.
Molecules ; 24(23)2019 Nov 26.
Article in English | MEDLINE | ID: mdl-31779154

ABSTRACT

Targeted alpha-particle therapy (TAT) aims to selectively deliver radionuclides emitting α-particles (cytotoxic payload) to tumors by chelation to monoclonal antibodies, peptides or small molecules that recognize tumor-associated antigens or cell-surface receptors. Because of the high linear energy transfer (LET) and short range of alpha (α) particles in tissue, cancer cells can be significantly damaged while causing minimal toxicity to surrounding healthy cells. Recent clinical studies have demonstrated the remarkable efficacy of TAT in the treatment of metastatic, castration-resistant prostate cancer. In this comprehensive review, we discuss the current consensus regarding the properties of the α-particle-emitting radionuclides that are potentially relevant for use in the clinic; the TAT-mediated mechanisms responsible for cell death; the different classes of targeting moieties and radiometal chelators available for TAT development; current approaches to calculating radiation dosimetry for TATs; and lead optimization via medicinal chemistry to improve the TAT radiopharmaceutical properties. We have also summarized the use of TATs in pre-clinical and clinical studies to date.


Subject(s)
Alpha Particles/therapeutic use , Neoplasms/radiotherapy , Radiopharmaceuticals/therapeutic use , Animals , Antibodies, Monoclonal/therapeutic use , Humans , Radioisotopes/therapeutic use , Radiometry/methods
18.
J Org Chem ; 82(17): 9023-9029, 2017 09 01.
Article in English | MEDLINE | ID: mdl-28776371

ABSTRACT

A highly efficient asymmetric synthesis of the key tetrahydropyranol intermediate of DPP-4 inhibitor omarigliptin (1) is described. The successful development of a protecting-group- and precious-metal-free synthesis was achieved via the discovery of a practical asymmetric Henry reaction and the application of a one-pot nitro-Michael-lactolization-dehydration through-process. Other features of the synthesis include a highly efficient MsCl-mediated dehydration and a crystallization-induced dynamic resolution for exceptional ee and dr upgrade. The synthesis of this complex intermediate utilizes simple starting materials and proceeds in four linear steps.


Subject(s)
Dipeptidyl-Peptidase IV Inhibitors/chemical synthesis , Heterocyclic Compounds, 2-Ring/chemical synthesis , Pyrans/chemical synthesis , Dipeptidyl-Peptidase IV Inhibitors/chemistry , Heterocyclic Compounds, 2-Ring/chemistry , Molecular Structure , Pyrans/chemistry
19.
Regul Toxicol Pharmacol ; 90: 22-28, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28822875

ABSTRACT

The ICH M7 Option 4 control of (potentially) mutagenic impurities is based on the use of scientific principles in lieu of routine analytical testing. This approach can reduce the burden of analytical testing without compromising patient safety, provided a scientifically rigorous approach is taken which is backed up by sufficient theoretical and/or analytical data. This paper introduces a consortium-led initiative and offers a proposal on the supporting evidence that could be presented in regulatory submissions.


Subject(s)
Drug Contamination/prevention & control , Mutagenicity Tests/standards , Mutagens/toxicity , Pharmaceutical Preparations/standards , Technology, Pharmaceutical/standards , Computer Simulation , Humans , Mutagenicity Tests/methods , Pharmaceutical Preparations/chemical synthesis , Practice Guidelines as Topic , Quality Control , Quantitative Structure-Activity Relationship , Risk Assessment
20.
J Org Chem ; 81(20): 10009-10015, 2016 10 21.
Article in English | MEDLINE | ID: mdl-27700080

ABSTRACT

A novel method for the oxidation of indolines to indoles is described. The method uses a Cu(I) catalyst and an organic percarbonate as the stoichiometric oxidant. The procedure was successfully applied at 0.5 kg scale in the production of a key intermediate in the synthesis of Elbasvir, which is a novel therapy for the treatment of hepatitis C virus infection.


Subject(s)
Copper/chemistry , Indoles/chemistry , Catalysis , Oxidation-Reduction , Spectrum Analysis/methods
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