Martin Churchill

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Tumour necrosis factor-alpha (TNF-alpha) is a potent pro-inflammatory and immunomodulatory cytokine implicated in inflammatory conditions such as rheumatoid arthritis, Crohn's disease, multiple sclerosis and the cachexia associated with cancer or human immunodeficiency virus infection. TNF-alpha is initially expressed as a 233-amino-acid membrane-anchored(More)
Tumor necrosis factor-alpha (TNF-alpha) is released from a cell membrane-anchored precursor by proteolytic cleavage. We have shown that broad spectrum synthetic inhibitors of matrix metalloproteinases (MMPs) prevent the processing of the TNF precursor but do not inhibit the release of other cytokines. Purified MMPs, stromelysin, matrilysin, collagenase, and(More)
Semantic specifications of programming languages typically have poor modularity. This hinders reuse of parts of the semantics of one language when specifying a different language -- even when the two languages have many constructs in common -- and evolution of a language may require major reformulation of its semantics. Such drawbacks have discouraged(More)
The HIV-1 gene promoter is a bi-directional promoter of transcription. We report the characterization of the negative sense promoter (NSP) by analysis of the effect on negative sense transcription of a series of LTR U3 region substitution mutants. Mutations in the region nt −58 to −183 (positive sense transcription initiation nt +1) reduced transcription to(More)
For structural operational semantics (SOS) of process algebras, various notions of bisimulation have been studied, together with rule formats ensuring that bisimilarity is a congruence. For programming languages, however, SOS generally involves auxiliary entities (e.g. stores) and computed values, and the standard bisimulation and rule formats are not(More)
Game semantics extends the Curry-Howard isomorphism to a three-way correspondence: proofs, programs, strategies. But the universe of strategies goes beyond intuitionistic logics and lambda calculus, to capture stateful programs. In this paper we describe a logical counterpart to this extension, in which proofs denote such strategies. We can embed(More)
Game semantics has been used to interpret both proofs and functional programs: an important further development on the programming side has been to model higher-order programs with state by allowing strategies with “history-sensitive” behaviour. In this paper, we develop a detailed analysis of the structure of these strategies from a logical perspective by(More)
Transition rules with negative premises are needed in the structural operational semantics of programming and specification constructs, such as priority and interrupt, as well as in timed extensions of specification languages. The well-known proof-theoretic semantics for transition system specifications involving negative premises is based on well-supported(More)
A result on observational equivalence for PCF and innocent strategies, as presented at the Games for Logic and Programming Languages (GaLoP) workshop in York, March 2009. The full abstraction result for PCF using game semantics requires one to identify all innocent strategies that are innocently indistinguishable. This involves a quantification over all(More)
Recent work has identified heterozygous mutations in DNMT3a in 4.1–22.1% of patients with acute myeloid leukemia (AML). Here we show that 3.3% of patients with high risk myelodysplastic syndrome (MDS) also possess heterozygous mutations in the methyltransferase domain of DNMT3a. Our results suggest that DNMT3a mutations may precede the development of AML.(More)