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A R Jones

Publications and source records attributed to A R Jones.

At least 19 recordsLinked to original sources
PubMed2006

Radioactive materials in biosolids: dose modeling.

The Interagency Steering Committee on Radiation Standards (ISCORS) has recently completed a study of the occurrence within the United States of radioactive materials in sewage sludge and sewage incineration ash. One component of that effort was an examination of the possible transport of radioactivity from sludge into the local environment and the subsequent exposure of humans. A stochastic environmental pathway model was applied separately to seven hypothetical, generic sludge-release scenarios, leading to the creation of seven tables of Dose-to-Source Ratios (DSR), which can be used in translating from specific activity in sludge into dose to an individual. These DSR values were then combined with the results of an ISCORS survey of sludge and ash at more than 300 publicly owned treatment works, to explore the potential for radiation exposure of sludge workers and members of the public. This paper provides a brief overview of the pathway modeling methodology employed in the exposure and dose assessments and discusses technical aspects of the results obtained.

Environmental Monitoring↗
PubMed2005

Whole-grain intake of British young people aged 4-18 years.

Inverse associations between whole-grain food consumption and risk of CVD, some cancers and type 2 diabetes have been reported. However, there are few reports of whole-grain intake, particularly among young people. The objective of the present study was to estimate whole-grain intake in a nationally representative sample of young people aged 4-18 years living in Great Britain. Whole-grain intake was estimated using 7 d weighed dietary records from 1583 young people who participated in the cross-sectional National Diet and Nutrition Survey in 1997. Whole-grain intake was quantified from the consumption of all foods containing > or =10 % whole-grain content. Median whole-grain intake was 7 g/d (interquartile range 0-19 g/d), with a corresponding mean of 13 (sd 18) g/d. Intake was significantly lower among young people whose head of household had a manual occupation, but did not differ significantly by sex, age, region or season. There was no whole-grain intake for 27 % of participants. The percentages for less than one and less than three 16 g amounts of whole-grain intake per d were 70 and 94, respectively, while corresponding percentages based on 20 g amounts were 76 and 97. Foods with <51 % whole-grain content provided 28 % of whole-grain intake overall, with a higher percentage in older adolescents. The main sources of whole-grain intake were breakfast cereals (56 %) and bread (25 %). The present study provides the first quantification of absolute whole-grain intake from all significant food sources in any representative age group in the UK. Although there is some debate regarding the quantity of whole grains required for good health, whole-grain intake among British young people is low.

Adolescent↗
PubMed2004

Control of glycolysis in mature boar spermatozoa: effect of pH in vitro.

The glycolytic pathway in boar sperm is sensitive to pH, which decreases as lactate is produced from either glucose or fructose in vitro. The build up of lactate appears to be due to the saturation of mitochondrial lactate transporters, which causes the cytoplasmic pH to fall. Phosphofructokinase has been shown to be sensitive to this drop in pH rather than to the build up of lactate ions or ATP, thereby controlling the rate of glycolysis in vitro.

Animals↗
PubMed2002

The effect of (R,S)-ornidazole on the fertility of male mice and the excretion and metabolism of 36Cl-(R,S)-ornidazole and 36Cl-(R,S)-alpha-chlorohydrin in male mice and rats.

(R,S)-Ornidazole, an effective antifertility agent for male rats at 400 mg/kg/day, was ineffective at this dose in male mice and at 1000 mg/kg/day caused neural effects. The compound was not excreted unchanged and more polar metabolites and Cl- were detected in 0-8 h urine following a single injection (400 mg/kg). In 8-24 h urine even these metabolites and most Cl ion were absent, indicating rapid metabolism of ornidazole. There was no organ specific accumulation of 36Cl-(R,S)-ornidazole in murine tissues. After injection of 36Cl-(R,S)-alpha-chlorohydrin, another antifertility agent in the rat but not the mouse, there was also no tissue-specific accumulation of radioactivity in the reproductive tract of either species. Urinary excretion rates of alpha-chlorohydrin were twice as rapid in mice as in rats. In mice, alpha-chlorohydrin was the major urinary metabolite, but in the rat metabolites included Cl-, 3-chlorolactate (BCLA) at 5 and 10 h and BCLA only at 24 h. BCLA was the major metabolite detected in most tissues at 10 and 24 h. In the rat cauda (but not caput) epididymidis the glycolytic inhibitor 3-chlorolactaldehyde was present at 5 h (but not 10 h), indicative of early metabolism. These results demonstrate a greater metabolism and excretion of putative antifertility agents in the mouse than the rat, lowering the amount of effective inhibitor circulating in the animal, which may explain why (R,S)-alpha-chlorohydrin and (R,S)-ornidazole are ineffective in this species at the dosages and injection times used, despite their spermatozoa being sensitive to inhibition by (R,S)-alpha-chlorohydrin in vitro.

Amebicides↗
PubMed2002

Lack of antifertility properties of novel halogenated glycolytic inhibitors and the urinary excretion and metabolism of 1,6-dichloro-1,6-dideoxy-D-fructofuranose in the male rat.

The antifertility action of (R,S)-alpha-chlorohydrin administered orally to male rats was compared with that of several novel chlorinated compounds known to inhibit glycolysis and the kinematics of rat sperm in vitro. Oral gavage of 1,6-dichloro-1,6-dideoxy-D-fructofuranose (dichlorodideoxyfructose, DCF), 1-chloro-3-hydroxypropanone, its dimethylketal and bromopyruvate did not reduce the fertility of male rats below that of controls at the equivalent antifertility dose of (R,S)-alpha-chlorohydrin (5 mg/kg/day) or higher. As anticipated for a compound cleaved to products of (S)-chirality even high doses of DCF (200 mg/kg) showed no effect on renal function. 36Cl-Labelled DCF administered orally to male rats was eliminated only slowly in the urine (16% of the ingested dose excreted in 96 h). In the first 8 h, approximately 50% of DCF was excreted unchanged, 30% was excreted as 3-chlorolactate (BCLA), the oxidation product 3-chlorolactaldehyde and 25% as Cl-. By 24 h little DCF remained and the major metabolite (70%) was BCLA and 20% Cl-. The high rate of dechlorination is most likely responsible for the low antifertility action of DCF.

Acetone↗
PubMed2001

Using benthic recruitment to assess the significance of contaminated sediments: the influence of taxonomic resolution.

The use of small-scale experimental units as a means of evaluating the ecological effects of contaminated sediments was examined at the species, family, mixed and phylum levels of taxonomic resolution. Sediments were taken from various locations representing a range of contaminant loads. Containers with these sediments were placed in situ at a relatively uncontaminated location for 90 days. The containers were retrieved and the abundance of the macrofauna which recruited to the containers was estimated. The results showed that the composition of the benthic communities in the more highly contaminated sediments differed significantly from those in less contaminated sediments. Analyses at the different taxonomic levels showed that all but the phylum level data showed some differences in community structure among sediment types. The study showed that small-scale experiments are useful for examining the effects of contaminants and that higher levels of taxonomic resolution can be used to describe variations in the structure of benthic communities at this spatial scale.

Animals↗
PubMed2001

Smoke alarm ownership and installation: a comparison of a rural and a suburban community in Georgia.

As part of a smoke alarm giveaway and installation program (The Get-Alarmed Campaign), a total of 454 households were surveyed in two counties in Georgia, one metropolitan and one nonmetropolitan. The targeted communities in these counties had a high prevalence of low-income and minority populations and thus were at high risk of house fire-related morbidity and mortality. The objectives of the program were to determine the prevalence of and predictors for installed, functioning smoke alarms, and to install at least one smoke alarm and/or smoke alarm batteries in 100% of participating homes in need. Characteristics associated with smoke alarm ownership included home ownership, having a higher income, and having a central heating source, factors which should be considered in targeting future intervention strategies. At onset, 159/454 households (35.0%) had no smoke alarms installed and 56/275 households with existing smoke alarms (20.4%) had none that were functional. Regardless of ownership status, a free smoke alarm was installed in the household of 93.8% of participants and new batteries were installed in existing smoke alarms for 31.7% of participants. This project illustrates the usefulness of a door-to-door campaign in increasing smoke alarm ownership in both a rural and a suburban community with a high concentration of residents at high risk of house fire-related morbidity and mortality.

Accident Prevention↗
PubMed2001

Expression profiling using microarrays fabricated by an ink-jet oligonucleotide synthesizer.

We describe a flexible system for gene expression profiling using arrays of tens of thousands of oligonucleotides synthesized in situ by an ink-jet printing method employing standard phosphoramidite chemistry. We have characterized the dependence of hybridization specificity and sensitivity on parameters including oligonucleotide length, hybridization stringency, sequence identity, sample abundance, and sample preparation method. We find that 60-mer oligonucleotides reliably detect transcript ratios at one copy per cell in complex biological samples, and that ink-jet arrays are compatible with several different sample amplification and labeling techniques. Furthermore, results using only a single carefully selected oligonucleotide per gene correlate closely with those obtained using complementary DNA (cDNA) arrays. Most of the genes for which measurements differ are members of gene families that can only be distinguished by oligonucleotides. Because different oligonucleotide sequences can be specified for each array, we anticipate that ink-jet oligonucleotide array technology will be useful in a wide variety of DNA microarray applications.

Cells, Cultured↗
PubMed2001

Time to think: temporal considerations in nursing practice and research.

UNLABELLED: AIMS OF THE STUDY/PAPER: To explore the meaning of nursing time, both as it is represented in the literature and interpreted within nursing practice. To explore how nursing time may be better conceptualized through exploring non-nursing literature and the use of theory derivation. BACKGROUND/RATIONALE: The dynamic of time is one of the most important influences upon nursing behaviour, yet temporal issues have attracted very little attention in the literature regarding nursing practice, theory and research. DESIGN/METHOD: In the course of this literature review an attempt is made, via the process of theory derivation, to clarify the meaning of 'nursing time', and how nursing time is valued and perceived by others. RESULTS/FINDINGS: The literature reveals misconceptions and a lack of value of nursing time, possibly indicative of the dominance of linear models of time (such as clock and calendar time), and the historical ascendancy of medicine and the positivistic sciences over nursing. It is proposed here that nurses exist and practice within nonlinear, complex and parallel temporal worlds; these are considered by examining research data that illustrates a moment in nursing time. Exploring this moment gives an opportunity to introduce some terms and concepts that may be useful in the future conceptualization of nursing time. CONCLUSIONS: It is recommended that attention to such factors as the complex temporal dynamics inherent within health care in general, and nursing in particular, should be considered within the domains of nursing practice and research. This may help in distinguishing the fundamental identity and nature of nursing within health care and health care professions.

Humans↗
PubMed2001

Root mucilage from pea and its utilization by rhizosphere bacteria as a sole carbon source.

Plant roots secrete a complex polysaccharide mucilage that may provide a significant source of carbon for microbes that colonize the rhizosphere. High molecular weight mucilage was separated by high-pressure liquid chromatography gel filtration from low molecular weight components of pea root exudate. Purified pea root mucilage generally was similar in sugar and glycosidic linkage composition to mucilage from cowpea, wheat, rice, and maize, but appeared to contain an unusually high amount of material that was similar to arabinogalactan protein. Purified pea mucilage was used as the sole carbon source for growth of several pea rhizosphere bacteria, including Rhizobium leguminosarum 8401 and 4292, Burkholderia cepacia AMMD, and Pseudomonas fluorescens PRA25. These species grew on mucilage to cell densities of three- to 25-fold higher than controls with no added carbon source, with cell densities of 1 to 15% of those obtained on an equal weight of glucose. Micromolar concentrations of nod gene-inducing flavonoids specifically stimulated mucilage-dependent growth of R. leguminosarum 8401 to levels almost equaling the glucose controls. R. leguminosarum 8401 was able to hydrolyze p-nitrophenyl glycosides of various sugars and partially utilize a number of purified plant polysaccharides as sole carbon sources, indicating that R. leguminosarum 8401 can make an unexpected variety of carbohydrases, in accordance with its ability to extensively utilize pea root mucilage.

Amino Acids↗
PubMed2000

Functional discovery via a compendium of expression profiles.

Ascertaining the impact of uncharacterized perturbations on the cell is a fundamental problem in biology. Here, we describe how a single assay can be used to monitor hundreds of different cellular functions simultaneously. We constructed a reference database or "compendium" of expression profiles corresponding to 300 diverse mutations and chemical treatments in S. cerevisiae, and we show that the cellular pathways affected can be determined by pattern matching, even among very subtle profiles. The utility of this approach is validated by examining profiles caused by deletions of uncharacterized genes: we identify and experimentally confirm that eight uncharacterized open reading frames encode proteins required for sterol metabolism, cell wall function, mitochondrial respiration, or protein synthesis. We also show that the compendium can be used to characterize pharmacological perturbations by identifying a novel target of the commonly used drug dyclonine.

Cell Wall↗
PubMed2000

Early outcomes after allogeneic stem cell transplantation for leukemia and myelodysplasia without protective isolation: a 10-year experience.

Although it is common practice to use some form of isolation to protect allogeneic stem cell transplant patients from infection, the necessity for these practices in all environments has not been demonstrated. The current study evaluated patterns of infection and 100-day transplant-related mortality in 288 patients with myelodysplasia and leukemia transplanted without isolation. Patients were allowed out of hospital at any time within constraints of the medication schedule. Fever, foci of infection, and positive cultures within 28 days and death within 100 days because of the transplant procedure were recorded. Fever occurred in 57% of patients, and 10% had a clinical or radiographic focus of infection. Most infections were apparently endogenous; blood cultures from 24% of recipients grew organisms, 87% of which were gram-positive bacteria. Four patients (1%) died with aspergillus infection in circumstances indicating that isolation would not have been helpful. Twenty percent of patients remained without evidence of infection throughout. Transplant-related mortality at 100 days was 1% for 108 patients with early leukemia receiving transplants from matched siblings. For patients at higher risk, by virtue of donor and/or disease status, mortality was 21%. These figures compare favorably with those reported to the International Bone Marrow Transplant Registry, the majority of patients having been subjected to some form of isolation. We conclude that allogeneic stem cell transplantation can be safely performed in some environments without confining patients continuously to the hospital.

Adolescent↗
PubMed2000

Widespread aneuploidy revealed by DNA microarray expression profiling.

Expression profiling using DNA microarrays holds great promise for a variety of research applications, including the systematic characterization of genes discovered by sequencing projects. To demonstrate the general usefulness of this approach, we recently obtained expression profiles for nearly 300 Saccharomyces cerevisiae deletion mutants. Approximately 8% of the mutants profiled exhibited chromosome-wide expression biases, leading to spurious correlations among profiles. Competitive hybridization of genomic DNA from the mutant strains and their isogenic parental wild-type strains showed they were aneuploid for whole chromosomes or chromosomal segments. Expression profile data published by several other laboratories also suggest the use of aneuploid strains. In five separate cases, the extra chromosome harboured a close homologue of the deleted gene; in two cases, a clear growth advantage for cells acquiring the extra chromosome was demonstrated. Our results have implications for interpreting whole-genome expression data, particularly from cells known to suffer genomic instability, such as malignant or immortalized cells.

Aneuploidy↗
PubMed2000

Metabolism of the putative antifertility agents 3-(36)chloro-1-hydroxypropanone and its dimethyl ketal in the male rat.

3-(36)Chloro-1-hydroxypropanone (CHOP), a specific inhibitor of sperm glycolysis in vitro, is rapidly metabolized by the male rat to alpha-chlorohydrin, 3-chlorolactate and the inhibitory sperm metabolite, 3-chlorolactaldehyde, presumably all being of the (S)-configuration. The dimethyl ketal of (36)Cl-CHOP [3-(36)Cl-dimethyl-CHOP] is rapidly metabolized producing identical metabolites and excreted radioactivity in urine at a similar rate. As neither compound produced diuresis, glucosuria or induced the formation of spermatocoeles, conditions associated with related male antifertility and antiglycolytic agents, they could represent an alternative means of producing (S)-3-chlorolactaldehyde within spermatozoa in vivo.

Acetone↗
PubMed2000

Testicular microlithiasis in a UK population: its incidence, associations and follow-up.

OBJECTIVES: To determine the incidence of testicular microlithiasis in men presenting for testicular ultrasonography, to identify any associated pathology (with particular reference to testicular neoplasia) and to report the follow-up of those patients in whom testicular microlithiasis was identified. PATIENTS AND METHODS: In this retrospective study, the results of all testicular ultrasonography undertaken between July 1995 and March 1998 in a district general hospital were reviewed. The records of all patients diagnosed ultrasonographically to have testicular microlithiasis were retrieved and the pathology database was accessed for all testicular tumours diagnosed in the same period. RESULTS: During the study period 2215 scans were taken; 34 cases of testicular microlithiasis were identified, giving an incidence of 1.4%. Thirty-one testicular tumours were removed during the same period. Of the 34 cases with testicular microlithiasis, five had histologically confirmed testicular tumours (15%). The incidence of testicular tumours in the scans showing no microlithiasis was 26 in 2181 (1.1%). The differential incidence of tumours in the two groups is statistically significant (P < 0.001, chi-square analysis). Patients with testicular microlithiasis but no tumour were followed up for a median (range) of 41 (19-54) months; no interval tumours have developed to date. CONCLUSION: This study confirms an incidence of testicular microlithiasis comparable with that in other reported series, albeit in a selected population. There was a strong association between testicular microlithiasis and testicular tumours. Whether this is a causal relationship has yet to be determined. Careful clinical and ultrasonographic follow-up of these patients is therefore recommended until the significance of testicular microlithiasis is clear.

Adult↗