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Biomedical subjects

Paul Watson

Publications and source records attributed to Paul Watson.

11 recordsLinked to original sources
PubMed2006

Determination of (234)U/ (238)U isotope ratios in environmental waters by quadrupole ICP-MS after U stripping from alpha-spectrometry counting sources.

The 234U/238U isotope ratio has been widely used as a tracer for geochemical processes in underground aquifers. Quadrupole-based inductively coupled plasma mass spectrometry (ICP-MS) equipped with a high-efficiency nebulizer and a membrane desolvator was employed for the determination of 234U/238U isotope ratios in natural water samples. The instrumental limit of detection for 234U was at the low pg L(-1) level with very low sample consumption. Measurement precision (234U/238U) was 3-5% for bottled mineral water with elevated uranium concentration (>1 microg L(-1)). For the analysis of groundwater samples from the Almonte-Marisma underground aquifer (Huelva, Spain), uranium was stripped from stainless steel planchets that had previously been used as radiometric counting sources for alpha-particle spectrometry. Potential spectral interferences from other metals introduced during the dissolution were investigated. Matrix-matched blank solutions were needed to subtract the background on 234U due to the formation of platinum argides, and to allow for mass bias correction and background correction. The Pt appears to be an impurity present in the stainless steel, either as a minor component by itself or after extraction from the anode and a subsequent uranium electrodeposition. The 234U/238U isotope ratio data were in very good agreement with those of alpha spectrometry, while precision was improved by a factor of up to 10 and counting time was reduced down to approximately 20 min (10 replicate measurements).

Journal Article↗
PubMed2006

An audit of self acupuncture for chronic musculoskeletal pain.

BACKGROUND: Acupuncture is increasingly offered as a treatment for chronic pain, but continued treatment is expensive. Self acupuncture might offer a cost effective alternative. The aim of this project was to investigate the effectiveness and safety of self acupuncture in a pain clinic. METHODS: A retrospective audit was conducted by postal questionnaire of all patients with chronic pain who were taught self acupuncture as a home pain management strategy in the previous three years. The study was conducted by a researcher not involved in the patient's treatment. The patients selected for self acupuncture were those who had responded to acupuncture previously, met certain criteria, and had been taught self acupuncture successfully. Patients were taught self acupuncture using three acupuncture points (LI4, ST44, LR3). RESULTS: Of 52 eligible patients (70% female) who were approached, 38 valid questionnaires were returned, giving a response rate of 73.1% . Of these, 76.3% were female; 86.8% (33) still used self acupuncture and 13.3% (5) had stopped; 86.8% of the patients continued to experience pain reduction with self acupuncture. The reported pain relief gained was 5.7 (SD 2.6) measured on a visual analogue scale, improvement in quality of life was reported by 73.7% and no serious adverse effects were reported. CONCLUSION: This audit suggests that self acupuncture is effective for pain relief and improves quality of life in this selected group of patients. Safety can be maintained provided that pre-selection is done with care, and appropriate training is carried out. Self acupuncture has considerable potential to reduce clinic waiting lists and appointment times for patients. Further research is required to determine the cost effectiveness of this approach.

Acupuncture Therapy↗
PubMed2003

A web-based platform for virtual screening.

A fully integrated, web-based, virtual screening platform has been developed to allow rapid virtual screening of large numbers of compounds. ORACLE is used to store information at all stages of the process. The system includes a large database of historical compounds from high throughput screenings (HTS) chemical suppliers, ATLAS, containing over 3.1 million unique compounds with their associated physiochemical properties (ClogP, MW, etc.). The database can be screened using a web-based interface to produce compound subsets for virtual screening or virtual library (VL) enumeration. In order to carry out the latter task within ORACLE a reaction data cartridge has been developed. Virtual libraries can be enumerated rapidly using the web-based interface to the cartridge. The compound subsets can be seamlessly submitted for virtual screening experiments, and the results can be viewed via another web-based interface allowing ad hoc querying of the virtual screening data stored in ORACLE.

Algorithms↗
PubMedDate not supplied

Virtual screening using protein-ligand docking: avoiding artificial enrichment.

This study addresses a number of topical issues around the use of protein-ligand docking in virtual screening. We show that, for the validation of such methods, it is key to use focused libraries (containing compounds with one-dimensional properties, similar to the actives), rather than "random" or "drug-like" libraries to test the actives against. We also show that, to obtain good enrichments, the docking program needs to produce reliable binding modes. We demonstrate how pharmacophores can be used to guide the dockings and improve enrichments, and we compare the performance of three consensus-ranking protocols against ranking based on individual scoring functions. Finally, we show that protein-ligand docking can be an effective aid in the screening for weak, fragment-like binders, which has rapidly become a popular strategy for hit identification. All results presented are based on carefully constructed virtual screening experiments against four targets, using the protein-ligand docking program GOLD.

Ligands↗