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Ashley Jones

Publications and source records attributed to Ashley Jones.

6 recordsLinked to original sources
PubMed2006

Gross anatomical, CT and MRI analyses of the buccal fat pad with special emphasis on volumetric variations.

The use of the buccal fat pad (BFP) has increased in popularity in recent years because of its reliability, ease of harvest, and low complication rate during oral and maxillofacial procedures. The aim of this study was to evaluate the volumetric variations of the BFP with a CT and MRI, as well as the thickness, weight and volume with conventional methods. We have examined the BFP from 80 formalin fixed adult cadavers (mean age 59) derived from both males (45) and females (35). In addition, we also examined 20 cadaveric BFPs using MR and CT imaging. Digital image analysis software was used to measure the volumetric distribution and to characterize the morphology of BFP. The BFP can be divided into three lobes (anterior, intermediate, and posterior) and has four extensions (buccal, pterygoid, pterygopalatine, and temporal). The BFP is fixed by six ligaments, to the maxilla, posterior zygoma, inner and outer rim of infraorbital fissure, temporalis tendon, and buccinator membrane. The mean volume in males was 10.2 ml and ranged 7.8-11.2 ml, while in females the mean volume was 8.9 ml and ranged 7.2-10.8 ml. Additionally, the mean thickness was 6 mm, with a mean weight of 9.7 g. These facts may be important when considering the use of the BFP in reconstruction, particularly whether the correct volume has been removed from each side in aesthetic, oral, or maxillofacial procedures.

Adipose Tissue↗
PubMed2005

Once-daily netilmicin for neutropenic pyrexia in paediatric oncology.

AIM: To establish the safety and efficacy of single daily intravenous netilmicin 6 mg/kg with piperacillin 100 mg/kg every 8 h for empirical, first-line management of children with neutropenic pyrexia following cytotoxic chemotherapy. METHODS: Observational study of children admitted to a regional oncology unit from October 1999-April 2002. Primary outcome measure was temperature 72 h after commencing antibiotic therapy; secondary measures were mortality, nephrotoxicity, symptomatic ototoxicity and serum netilmicin levels. RESULTS: 280 episodes for 128 patients (median age 7.1 y) were documented, and 248 episodes were evaluated and compared with a previous cohort of 100 episodes for which the only difference was administration of netilmicin three times daily. Twenty-seven per cent of single-dose netilmicin episodes remained febrile at 72 h compared to 32% in the comparator group (difference -4.7%; 95 % CI: -6.8% to 16.2%; p = 0.41). No patients died and we were unable to find evidence of nephrotoxicity or ototoxicity. Eighty-nine per cent of "peak" serum netilmicin levels measured 30 min after infusion were 10 mg/l or greater, and 94% and 86% measured 12-16 h after the first and third dose, respectively, were 1 mg/l or less. Peak serum netilmicin level measurements and 12-16-h measurements after the first dose were abandoned after the first 180 episodes. CONCLUSIONS: Netilmicin can safely be given as a single daily dose to children with febrile neutropenia who do not have biochemical evidence of nephrotoxicity. Monitoring peak serum levels of netilmicin is unnecessary. Levels taken 12-16 h after the third dose are adequate to monitor therapy if used in conjunction with a therapeutic guideline detailing the response to abnormal serum creatinine and netilmicin levels.

Adolescent↗
PubMed2005

Gene set coregulated by the Saccharomyces cerevisiae nonsense-mediated mRNA decay pathway.

The nonsense-mediated mRNA decay (NMD) pathway has historically been thought of as an RNA surveillance system that degrades mRNAs with premature translation termination codons, but the NMD pathway of Saccharomyces cerevisiae has a second role regulating the decay of some wild-type mRNAs. In S. cerevisiae, a significant number of wild-type mRNAs are affected when NMD is inactivated. These mRNAs are either wild-type NMD substrates or mRNAs whose abundance increases as an indirect consequence of NMD. A current challenge is to sort the mRNAs that accumulate when NMD is inactivated into direct and indirect targets. We have developed a bioinformatics-based approach to address this challenge. Our approach involves using existing genomic and function databases to identify transcription factors whose mRNAs are elevated in NMD-deficient cells and the genes that they regulate. Using this strategy, we have investigated a coregulated set of genes. We have shown that NMD regulates accumulation of ADR1 and GAL4 mRNAs, which encode transcription activators, and that Adr1 is probably a transcription activator of ATS1. This regulation is physiologically significant because overexpression of ADR1 causes a respiratory defect that mimics the defect seen in strains with an inactive NMD pathway. This strategy is significant because it allows us to classify the genes regulated by NMD into functionally related sets, an important step toward understanding the role NMD plays in the normal functioning of yeast cells.

Binding Sites↗
PubMed2003

Quantifying cell scattering: the blob algorithm revisited.

BACKGROUND: A method to objectively quantify cell scattering would permit quantitative evaluation of therapies and compounds intended to affect this physiologic process, which has relevance to normal (e.g., development) and pathologic (e.g., metastasis) events. METHODS: A grid-based modified blob analysis was performed on a set of images of Madin-Darby Canine Kidney (MDCK) cells to quantify the following parameters: the number of cellular clusters in each image, the size of the clusters in terms of pixel counts, and the number of cells in each cluster. These parameters were used as measures of cell scattering and were compared with subjective assessments of scattering made by three experienced examiners. RESULTS: The quantitative parameters correlated strongly to subjective assessments. The algorithm displayed a different concept of "clustering" than the examiners and consistently identified more clusters than did the examiners. There was close agreement in the number of cells counted. All three quantitative parameters correlated strongly to the subjective scattering scores, as follows: cluster count (r(s) = -0.765 to -0.789, P < 0.0001), cluster size in pixels (r(s) = 0.838 to 0.845, P < 0.0001), and cluster size in cells (r(s) = 0.758 to 0.804, P < 0.0001). The parameters were continuous, providing greater resolving power than ordinal subjective scores. CONCLUSIONS: The findings confirmed that our algorithm reproduces the traditional classification of scattering with improved resolution, quantification, and objectivity.

Algorithms↗
PubMed1999

Wobble board (ankle disc) training effects on the discrimination of inversion movements.

To assess the effect of a five-week training program using a wobble board on discrimination of discrete movements at the ankle, 40 ankles were tested from 20 subjects in a group of elite athletes. Players in a first grade rugby league squad were randomly allocated to either a wobble board training or no-training group. Pre-tests to assess discrimination of inversion movements made while standing were carried out on both ankles of all subjects using an automated device that enabled a normal share of weightbearing on the tested ankle. From a sequence of 160 inversion movements, a discrimination index was determined. This measure represents the relative difference in angular extent needed for an inversion movement to be differentiated 75 per cent of the time from the standard movement of 12.5 degrees below horizontal. Subjects were re-tested after either undertaking a five-week wobble board training program, or after having had no training. Discrimination of movements into inversion improved from the pre-test (Weber fraction 8.8 per cent) to the post training test (6.4 per cent) in the wobble board trained group. This discrimination improvement was significantly greater than the change in the untrained group (pre-test: 8.4 per cent and post-test: 8.1 per cent). These data demonstrate that wobble board training can improve discrimination of discrete ankle inversion movements, and support the Weber fraction as a measure of movement sensitivity.

Journal Article↗