Publications by authors named "Katrina Madden"

Background: Emerging evidence suggests that repetitive transcranial magnetic stimulation (rTMS) enhances cognition in mild cognitive impairment (MCI). Accelerated intermittent theta burst stimulation (iTBS) rTMS protocols are promising as they substantially reduce burden by shortening the treatment course, but the safety, feasibility, and acceptability of iTBS have not been established in MCI.

Methods: 24 older adults with amnestic MCI (aMCI) due to possible Alzheimer's disease enrolled in a phase I trial of open-label accelerated iTBS to the left dorsolateral prefrontal cortex (8 stimulation sessions of 600 pulses of iTBS/day for 3 days).

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Acute myeloid leukaemia (AML) is an aggressive type of leukaemia with low rates of long-term survival. While the current standard of care is based on cytotoxic chemotherapy, a promising emerging approach is differentiation therapy. However, most current differentiating agents target specific mutations and are effective only in certain patient subtypes.

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Barriers to the ready adoption of biocatalysis into asymmetric synthesis for early stage medicinal chemistry are addressed, using ketone reduction by alcohol dehydrogenase as a model reaction. An efficient substrate screening approach is used to show the wide substrate scope of commercial alcohol dehydrogenase enzymes, with a high tolerance to chemical groups employed in drug discovery (heterocycle, trifluoromethyl and nitrile/nitro groups) observed. We use our screening data to build a preliminary predictive pharmacophore-based screening tool using Forge software, with a precision of 0.

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Tuberculosis, a deadly infectious lung disease caused by (Mtb), remains the leading cause of bacterial disease-related deaths worldwide. Mtb reprograms and disables key antibacterial response pathways, many of which are regulated by epigenetic mechanisms that control the accessibility of chromatin to the transcriptional machinery. Recent reports suggest that host phosphatases, such as PPM1A, contribute to regulating chromatin accessibility during bacterial infections.

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Introduction: Complement-based drug discovery is undergoing a renaissance, empowered by new advances in structural biology, complement biology and drug development. Certain components of the complement pathway, particularly C1q and C3, have been extensively studied in the context of neurodegenerative disease, and established as key therapeutic targets. C5 also has huge therapeutic potential in this arena, with its druggability clearly demonstrated by the success of C5-inhibitor eculizumab.

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The androgen receptor (AR) is an important drug target in prostate cancer and a driver of castration-resistant prostate cancer (CRPC). A significant challenge in designing effective drugs lies in targeting constitutively active AR variants and, most importantly, nearly all AR variants lacking the ligand-binding domain (LBD). Recent findings show that an AR's constitutive activity may occur in the presence of somatic DNA mutations within non-coding regions, but the role of these mutations remains elusive.

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Despite much progress in developing better drugs, many patients with acute myeloid leukemia (AML) still die within a year of diagnosis. This is partly because it is difficult to identify therapeutic targets that are effective across multiple AML subtypes. One common factor across AML subtypes is the presence of a block in differentiation.

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Tuberculosis (TB) remains the leading cause of bacterial disease-related death and is among the top 10 overall causes of death worldwide. The complex nature of this infectious lung disease has proven difficult to treat, and significant research efforts are now evaluating the feasibility of host-directed, adjunctive therapies. An attractive approach in host-directed therapy targets host epigenetics, or gene regulation, to redirect the immune response in a host-beneficial manner.

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Palladium-catalyzed reactions are among the most commonly used procedures in organic synthesis. The products have a range of uses, including as intermediates in total synthesis and as screening compounds for drug discovery or agrochemical projects. Despite the known and potentially deleterious effects of low-level metal impurities in biological assays, the quantification of metal remaining in reaction products to verify the effective removal of the transition element is rarely reported.

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Induction of differentiation is a promising therapeutic strategy against acute myeloid leukemia. However, current differentiation therapies are effective only to specific patient populations. To identify novel differentiation agents with wider efficacy, we developed a phenotypic high-throughput screen with a range of genetically diverse cell lines.

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The reconnection of the scientific community with phenotypic drug discovery has created exciting new possibilities to develop therapies for diseases with highly complex biology. It promises to revolutionise fields such as neurodegenerative disease and regenerative medicine, where the development of new drugs has consistently proved elusive. Arguably, the greatest challenge in readopting the phenotypic drug discovery approach exists in establishing a crucial chain of translatability between phenotype and benefit to patients in the clinic.

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Two truncated analogues of the polyenyl photoprotective xanthomonadin pigments have been synthesised utilising an iterative Heck-Mizoroki (HM)/iododeboronation cross coupling approach and investigated as models of the natural product photoprotective agents in bacteria. Despite the instability of these types of compounds, both analogues proved to be sufficiently stable to allow isolation, spectroscopic analysis and biological studies of their photoprotective behaviour which showed that despite their shorter polyene chain length, they retained the ability to protect bacteria from photochemical damage; i.e.

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Vinyliodide reacts chemoselectively under Heck-Mizoroki conditions with terminal alkenes, including vinylboronate esters, to give dienes. The resulting dienylboronates undergo Suzuki-Miyaura couplings with aryl, heteroaryl and alkenyl halides to access dienes and trienes.

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This review provides insight into the variety of structures and biological activities found in the non-isoprenoid family of polyene natural products and examines the strategies and synthetic methods applied for the polyenic components in particular by way of examples.

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A new synthetic route to 3-(heteroaryl) tetrahydropyrazolo[3,4-c]pyridines has been developed that uses the Suzuki-Miyaura cross-coupling of a triflate 6 with (hetero)aryl boronic acids or esters. Using Pd(OAc)2 and XPhos or an XPhos precatalyst, a diverse range of substituents at the C3 position of the tetrahydropyrazolo[3,4-c]pyridine skeleton were prepared. The use of pivaloyloxymethyl and benzyl protection also offers the potential to differentially functionalize the pyrazole and tetrahydropyridine nitrogens.

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