Publications by authors named "Meredith S"

My invitation from this Journal's Editor, Felicia Cox, to provide a paper for this themed issue, included the sentence 'I was wondering if you or a colleague would like to contribute a back to basics article on the relevant standards and guidelines for decontamination, including what is compliance?'. The reason it is so interesting to me is that the term 'back to basics' implies reverting to a simpler time in life - when by just sticking to the rules, life became easier. However, with decontamination this is not actually true.

View Article and Find Full Text PDF

Humans have two major high density lipoprotein (HDL) sub-fractions, HDL(2) and HDL(3), whereas mice have a monodisperse HDL profile. Epidemiological evidence has suggested that HDL(2) is more atheroprotective; however, currently there is no direct experimental evidence to support this postulate. The amino acid sequence of apoA-I is a primary determinant of HDL subclass formation.

View Article and Find Full Text PDF

beta-Rich self-assembly is a major structural class of polypeptides, but still little is known about its atomic structures and biophysical properties. Major impediments for structural and biophysical studies of peptide self-assemblies include their insolubility and heterogeneous composition. We have developed a model system, termed peptide self-assembly mimic (PSAM), based on the single-layer beta-sheet of Borrelia outer surface protein A.

View Article and Find Full Text PDF

Polyglutamine (poly(Q)) expansion is associated with protein aggregation into beta-sheet amyloid fibrils and neuronal cytotoxicity. In the mutant poly(Q) protein huntingtin, associated with Huntington's disease, both aggregation and cytotoxicity may be abrogated by a polyproline (poly(P)) domain flanking the C terminus of the poly(Q) region. To understand structural changes that may occur with the addition of the poly(P) sequence, we synthesized poly(Q) peptides with 3-15 glutamine residues and a corresponding set of poly(Q) peptides flanked on the C terminus by 11 proline residues (poly(Q)-poly(P)), as occurs in the huntingtin sequence.

View Article and Find Full Text PDF

Purpose: The mechanical theory of glaucoma postulates that raised intraocular pressure (IOP) causes laminar distortion resulting in damage to axons at the optic nerve head. There is some evidence that the change in morphology may occur over a short time course. The aim of this paper was to detail the acute morphologic changes at the optic nerve head when IOP was lowered with medical therapy in a clinical population.

View Article and Find Full Text PDF

Beta-amyloid (Abeta) aggregates at low concentrations in vivo, and this may involve covalently modified forms of these peptides. Modification of Abeta by 4-hydroxynonenal (4-HNE) initially increases the hydrophobicity of these peptides and subsequently leads to additional reactions, such as peptide cross-linking. To model these initial events, without confounding effects of subsequent reactions, we modified Abeta at each of its amino groups using a chemically simpler, close analogue of 4-HNE, the octanoyl group: K16-octanoic acid (OA)-Abeta, K28-OA-Abeta, and Nalpha-OA-Abeta.

View Article and Find Full Text PDF

Objective: To assess the long term risks and benefits of hormone replacement therapy (combined hormone therapy versus placebo, and oestrogen alone versus combined hormone therapy).

Design: Multicentre, randomised, placebo controlled, double blind trial.

Setting: General practices in UK (384), Australia (91), and New Zealand (24).

View Article and Find Full Text PDF

Insulin-degrading enzyme (IDE) is a zinc metalloprotease that hydrolyzes amyloid-beta (Abeta) and insulin, which are peptides associated with Alzheimer disease (AD) and diabetes, respectively. Our previous structural analysis of substrate-bound human 113-kDa IDE reveals that the N- and C-terminal domains of IDE, IDE-N and IDE-C, make substantial contact to form an enclosed catalytic chamber to entrap its substrates. Furthermore, IDE undergoes a switch between the closed and open conformations for catalysis.

View Article and Find Full Text PDF

Non-somatic synaptic and axonal compartments of neurons are primary pathological targets in many neurodegenerative conditions, ranging from Alzheimer disease through to motor neuron disease. Axons and synapses are protected from degeneration by the slow Wallerian degeneration (Wld(s)) gene. Significantly the molecular mechanisms through which this spontaneous genetic mutation delays degeneration remain controversial, and the downstream protein targets of Wld(s) resident in non-somatic compartments remain unknown.

View Article and Find Full Text PDF

Stickler syndrome due to mutations in COL2A1 is usually the result of premature termination codons and nonsense mediated decay resulting in haploinsufficiency of type II collagen. Here we present two missense mutations and one apparently silent mutation that each result in Stickler syndrome, but via different molecular mechanisms. One alters the translation initiating ATG codon.

View Article and Find Full Text PDF

Background/aims: The type II collagenopathies are a phenotypically diverse group of genetic skeletal disorders caused by a mutation in the gene coding for type II collagen. Reports published before the causative mutations were discovered suggest heritable bone dysplasias with skeletal malformations may be associated with a vitreoretinopathy.

Methods: A retrospective notes search of patients with a molecularly characterised type II collagenopathy chondrodysplasia who had been examined in the ophthalmology clinic was conducted.

View Article and Find Full Text PDF

We describe the clinical findings in two patients with double heterozygosity, both involving Stickler syndrome. In case 1, the proposita had Albright hereditary osteodystrophy which was inherited from her mother and type 1 Stickler syndrome which was a new mutation. The combination of manifestations from the two syndromes had resulted in initial diagnostic confusion.

View Article and Find Full Text PDF

Background: This paper describes the results of a feasibility study for a randomised controlled trial (RCT).

Methods: Twenty-nine members of the UK Dermatology Clinical Trials Network (UK DCTN) expressed an interest in recruiting for this study. Of these, 17 obtained full ethics and Research & Development (R&D) approval, and 15 successfully recruited patients into the study.

View Article and Find Full Text PDF

The early stages of peptide and protein aggregation include the formation of soluble oligomers, some of which may be cytotoxic. There is a paucity of structural information on these oligomers, however, because they are temporally unstable and tend to aggregate further into insoluble protofibrils and fibrils. To obtain structural information on soluble oligomers, we have developed a procedure for encapsulating a fibril-forming peptide, Peptide 1 (NH2-SDDYYYGFGSNKFGRPRDD-COOH), in 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine single bilayer vesicles (POPC SBVs).

View Article and Find Full Text PDF

Purpose: To identify possible risk factors for the development of posterior vitreous detachment (PVD).

Design: Retrospective case-control study.

Methods: A total of 138 cases with PVD and 114 age-matched controls were accrued from two different sites.

View Article and Find Full Text PDF

Background: Despite its inhibitory control requirements, antisaccade deficits have been consistently associated with working memory impairments in schizophrenia. We investigated whether variance in antisaccade performance could be better accounted for in terms of a specific inhibitory function.

Method: We assessed 48 clinically stable out-patients with schizophrenia on an antisaccade task, as well as on measures of spatial and verbal working memory, sustained selective attention, and a simple motoric go/no-go measure of response inhibition.

View Article and Find Full Text PDF

This review considers the design, synthesis, and mechanistic assessment of peptide-based fibrillogenesis inhibitors, mainly focusing on beta-amyloid, but generalizable to other aggregating proteins and peptides. In spite of revision of the "amyloid hypothesis," the investigation and development of fibrillogenesis inhibitors remain important scientific and therapeutic goals for at least three reasons. First, it is still premature to dismiss fibrils altogether as sources of cytotoxicity.

View Article and Find Full Text PDF

Monoclonal antibodies have become important therapeutic agents against certain cancers. Many tumor-specific antigens are mutant proteins that are predominantly intracellular and thus not readily accessible to monoclonal antibodies. We found that a wild-type transmembrane protein could be transformed into a tumor-specific antigen.

View Article and Find Full Text PDF

Aim: To detail the clinical findings in a British family with molecularly characterised Wagner syndrome.

Background: Only in the last year has the specific genetic defect in Wagner syndrome been identified, and the background literature of the molecular genetics is outlined. Clinical and laboratory findings in a second case of Wagner syndrome are included to highlight difficulties that can be encountered when identifying pathogenic mutations for disorders arising in complex genes.

View Article and Find Full Text PDF

It seems likely that the development of effective diabetes education for patients, carers and staff would prove highly cost-effective. Diabetes-e is an electronic diabetes encyclopaedia designed to provide comprehensive education to patients, carers (e.g.

View Article and Find Full Text PDF

In a recent model of beta-amyloid (Abeta) fibrils, based mainly on solid-state NMR data, a molecular layer consists of two beta-sheets (residues 12-23 and 31-40 of Abeta1-40), folded onto one another by a connecting "bend" structure (residues 25-29) in the side-chain dimension. In this paper, we use two N-methyl amino acids to disrupt each of the two beta-sheets individually (2NMe(NTerm), residues 17 and 19; and 2NMe(CTerm), residues 37 and 39), or both of them at the same time (4NMe, with the above four N-methylated residues). Our data indicate that incorporation of two N-methyl amino acids into one beta-sheet is sufficient to disrupt that sheet while leaving the other, unmodified beta-sheet intact and able to form fibrils.

View Article and Find Full Text PDF

Protein aggregation is a prominent feature of many neurodegenerative diseases, such as Alzheimer's, Huntington's, and Parkinson's diseases, as well as spongiform encephalopathies and systemic amyloidoses. These diseases are sometimes called protein misfolding diseases, but the latter term begs the question of what is the "folded" state of proteins for which normal structure and function are unknown. Amyloid consists of linear, unbranched protein or peptide fibrils of approximately 100 A diameter.

View Article and Find Full Text PDF

Background: Fall-related injuries, a major public health problem in long-term care, may be reduced by interventions that improve safety practices. Previous studies have shown that safety practice interventions can reduce falls; however, in long-term care these have relied heavily on external funding and staff. The aim of this study was to test whether a training program in safety practices for staff could reduce fall-related injuries in long-term care facilities.

View Article and Find Full Text PDF