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J Parsons

Publications and source records attributed to J Parsons.

At least 37 records · Page 2Linked to original sources
PubMed2001

[IRepeat sequences of genomes of Rhizobium and Sinorhizobium meliloti: a comparative analysis].

Amongst prokaryotic genomes, those of nitrogen-fixing members of the Rhizobiaceae family are relatively large (6-9 Mb), often include mega-plasmids of 1.5-2 Mb, and contain numerous families of repeated DNA sequences. Although most essential nodulation and nitrogen fixation genes are well characterized, these represent only a small fraction of the DNA content. Little is known about the detailed structure of rhizobial genomes. With the development of sequencing techniques and new bio-informatic tools such studies become possible, however. Using the 2275 shotgun sequences of ANU265 (a derivative of NGR234 cured of pNGR234a), we have identified numerous families of repeats. Amongst these, the 58-bp-long NGRREP-4 represents the third most abundant DNA sequence after the RIME1 and RIME2 repeats, all of which are also found in Sinorhizobium meliloti. Surprisingly, studies on the distribution of these elements showed that in proportion to its size, the chromosome of NGR234 carries many more RIME modules than pNGR234a or pNGR234b. Together with the presence in NGR234 and S. meliloti 1021 of an insertion sequence (IS) element more conserved than essential nodulation and nitrogen fixation genes, these results give new insights into the origin and evolution of rhizobial genomes.

Base Sequence↗
PubMed2000

Activation of JNK3 alpha 1 requires both MKK4 and MKK7: kinetic characterization of in vitro phosphorylated JNK3 alpha 1.

JNK3 alpha 1 is predominantly a neuronal specific MAP kinase that is believed to require, like all MAP kinases, both threonine and tyrosine phosphorylation for maximal enzyme activity. In this study we investigated the in vitro activation of JNK3 alpha 1 by MAP kinase kinase 4 (MKK4), MAP kinase kinase 7 (MKK7), and the combination of MKK4 + MKK7. Mass spectral analysis showed that MKK7 was capable of monophosphorylating JNK3 alpha 1 in vitro, whereas both MKK4 and MKK7 were required for bisphosphorylation and maximal enzyme activity. Measuring catalysis under Vmax conditions showed MKK4 + MKK7-activated JNK3 alpha 1 had Vmax 715-fold greater than nonactivated JNK3 alpha 1 and MKK7-activated JNK3 alpha 1 had Vmax 250-fold greater than nonactivated JNK3 alpha 1. In contrast, MKK4-activated JNK3 alpha 1 had no increase in Vmax compared to nonactivated levels and had no phosphorylation on the basis of mass spectrometry. These data suggest that MKK7 was largely responsible for JNK3 alpha 1 activation and that a single threonine phosphorylation may be all that is needed for JNK3 alpha 1 to be active. The steady-state rate constants kcat, Km(GST-ATF2++), and Km(ATP) for both monophosphorylated and bisphosphorylated JNK3 alpha 1 were within 2-fold between the two enzyme forms, suggesting the addition of tyrosine phosphorylation does not affect the binding of ATF2, ATP, or maximal turnover. Finally, the MAP kinase inhibitor, SB203580, had an IC50 value approximately 4-fold more potent on the monophosphorylated JNK3 alpha 1 compared to the bisphosphorylated JNK3 alpha 1, suggesting only a modest effect of tyrosine phosphorylation on inhibitor binding.

Activating Transcription Factor 2↗
PubMed2000

Interventions for treating bacterial vaginosis in pregnancy.

BACKGROUND: Bacterial vaginosis has been associated with poor perinatal outcome. Since the infections are amenable to treatment, identification during pregnancy and treatment may reduce the risk of preterm birth and its consequences. OBJECTIVES: The objective of this review was to assess the effects of antibiotic treatment of bacterial vaginosis in pregnancy. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register. SELECTION CRITERIA: Randomised trials comparing one antibiotic regimen with placebo or no treatment, or which compare two or more alternative antibiotic regimens in pregnant women with bacterial vaginosis. DATA COLLECTION AND ANALYSIS: Trial quality assessments and data extraction were done independently by three reviewers. Study authors were contacted for additional information. MAIN RESULTS: Five trials involving 1504 women were included. These trials were of good quality. Antibiotic therapy was highly effective at eradicating infection during pregnancy as judged by 'test-of-cure' following therapy (odds ratio 0.22, 95% confidence interval 0.17 to 0.27). The effect of treating bacterial vaginosis during pregnancy showed a trend to less births before 37 weeks gestation (odds ratio 0.78, 95% confidence interval 0.60 to 1.02). The prevention of preterm birth less than 37 weeks gestation was most marked in the subgroup of women with a previous preterm birth (odds ratio 0.37, 95% confidence interval 0.23 to 0. 60). REVIEWER'S CONCLUSIONS: The current evidence does not support screening and treating all pregnant women for bacterial vaginosis to prevent preterm birth and its consequences. For women with a history of a previous preterm birth there is some suggestion that detection and treatment of bacterial vaginosis early in pregnancy may prevent a proportion of these women having a further preterm birth. It is not known whether this is associated with an improvement in neonatal well-being.

Anti-Bacterial Agents↗
PubMed2000

The SF-36 summary scales: problems and solutions.

To determine the accuracy of the SF-36 summary mental and physical health scales in reflecting their underlying subscales using the traditional method of scoring based on factor coefficients derived through principle components analysis and orthogonal rotation. A representative Australian population survey containing the SF-36 was used to obtain factor coefficients from principle components analysis and orthogonal rotation for scoring the physical component summary (PCS) and the mental component summary (MCS) of the SF-36 in the traditional way. In addition two other methods were used to produce coefficients. The first method used maximum likelihood extraction and oblique rotation. The second method fit a structural equation model to the data in a confirmatory factor analysis. The coefficients derived by each of the methods were applied to the data of a second representative population survey. This survey also provided data on physical and mental health status which allowed comparison of the summary scores and underlying subscales according to various health states. Neither of the scoring methods based on the exploratory factor analyses methods (orthogonal and oblique) produced summary scale scores, by age group, that adequately reflected the underlying subscales. When coefficients derived using structural equation modeling were fit to the data in a confirmatory factor analysis the MCS and PCS accurately reflected their underlying subscale scores. They also produced MCS and PCS scores for the various health states as would be expected from the underlying subscales. The traditional methods of scoring the SF-36 summary scales produce results that would not be expected from the underlying subscales. The problem was only corrected by fitting a structural equation model to the data in a confirmatory factor analysis. The results advise caution in the use of the SF-36 summary scales and suggests that alternative methods of developing factor coefficients need to be employed in studies using the SF-36 summary scales.

Adolescent↗
PubMed2000

Pharmacy-based needle exchange (PBNX) schemes in south east England: a survey of service providers.

AIMS: To describe the activities of service providers with regard to (i) the business operation and policies defining pharmacy-based needle exchange (PBNX) in South East England; (ii) the day-to-day work of PBNX outlets from the provider perspective; and (iii) problems encountered by PBNX providers. DESIGN: (i) Postal self-completion questionnaire to all participating PBNX community pharmacies in South East England; and (ii) postal self-completion questionnaire to needle exchange coordinators. SETTING: Community pharmacy needle exchanges. PARTICIPANTS: Pharmacists in charge of needle exchange; and needle exchange coordinators. FINDINGS: Data were collected (i) from 381/440 (86.7%) participating community pharmacists, and (ii) 32/36 (88.9%) of coordinators. The study found that PBNX was reaching injecting drug users (many of whom used PBNX regularly), and providing a wide range of injecting equipment. Although pharmacists reported that problems such as shoplifting occurred relatively frequently, more serious problems such as violence were relatively rare. However, PBNX pharmacists reported needing further training for themselves and their staff. Suggested improvements included better advertising of services and improving returns rates for used injecting equipment. CONCLUSION: Needle exchange can reasonably be provided by non-specialist health care professionals such as community pharmacists. However, attention should to be paid to the educational needs of service providers who also require adequate support.

Education, Pharmacy↗
PubMed2000

New use of Argyle trocar catheter: treatment of pelvic abscess following transvaginal ultrasound-directed follicle aspiration (UDFA).

This report describes the use of an Argyle trocar catheter for the drainage of pelvic abscesses following transvaginal ultrasound-directed follicle aspiration (UDFA) for oocyte collection. Three patients treated with this technique recovered uneventfully. We conclude that the use of an Argyle trocar catheter for colpotomy in the management of pelvic abscesses appears to be simple and effective.

Abscess↗
PubMed1999

The health-related quality-of-life of never smokers, ex-smokers, and light, moderate, and heavy smokers.

BACKGROUND: Health related quality-of-life is recognized as an important health outcome measure; how ever, it may also have a significant application in smoking reduction and cessation programs. METHODS: Representative population data (n = 3010) was used to compare the quality-of-life status of differ ent smoking categories with never smokers. RESULTS: Statistically significant differences in mean quality-of-life scores, as measured by the SF-36 health status questionnaire, were observed between never smokers, as the reference group, ex-smokers, all smokers, and light, moderate, and heavy smokers. Heavy smokers also scored significantly lower than both other groups of smokers, scoring as low as the 29th percentile of the population on the general health dimension and lower than the 36th percentile of the population on all the mental health dimensions. CONCLUSIONS: The design of public health smoking cessation programs should consider the varying characteristics of different segments of the smoking population. The advantages of improved quality-of-life may strengthen the argument for encouraging heavier smokers to become light smokers as a precursor to total cessation.

Adolescent↗
PubMed1999

A combined vaccine against hepatitis A and B in children and adolescents.

BACKGROUND: Pediatric monocomponent formulations of vaccines against hepatitis A and B have been proved to be safe and immunogenic in children. OBJECTIVES: To investigate the safety and immunogenicity of a combined hepatitis A/B vaccine in children 1 to 15 years of age. METHODS: Three doses of a combined vaccine containing 360 enzyme-linked immunosorbent assay units of hepatitis A antigen and 10 microg of hepatitis B surface antigen were administered in a 0-, 1-, 6-month schedule to three groups of children: a group of 1- to 6-year-olds (n = 60); and two groups of 6- to 15-year-olds (both n = 60). RESULTS: Reactogenicity, assessed using diary cards, was not affected by the age of the subjects or the vaccine lot and was similar to that described with the monocomponent vaccines. Local and systemic reactions were mostly mild or moderate and resolved spontaneously. One month after the second dose 100 and 98.8% of all three groups had seroconverted against hepatitis A virus and hepatitis B virus, respectively. After the third dose all subjects were seropositive for both components, with geometric mean titers for anti-hepatitis A virus of 6518 to 8907 mIU/ml and for anti-hepatitis B surface antibody of 7255 to 11732 mIU/ml in the three groups. CONCLUSION: The combined pediatric hepatitis A/B vaccine formulation was well-tolerated and highly immunogenic in children 1 to 15 years old.

Adolescent↗
PubMed1999

Preradiotherapy computed tomography as a predictor of local control in supraglottic carcinoma.

PURPOSE: To determine the utility of pretreatment computed tomography (CT) for predicting primary site control in patients with supraglottic squamous cell carcinoma (SCC) treated with definitive radiotherapy (RT). MATERIALS AND METHODS: Pretreatment CT studies in 63 patients were reviewed. Minimum length of follow-up was 2 years. Local recurrence and treatment complications resulting in permanent loss of laryngeal function were documented. Tumor volume was calculated using a computer digitizer, and pre-epiglottic space (PES) spread was estimated. The data were analyzed using a combination of Fisher's exact test, logistic regression modeling, and multivariate analyses. Five-year local control rates were calculated using the product-limit method. RESULTS: Local control rates were inversely and roughly linearly related to tumor volume, although there seemed to be a threshold volume at which primary site prognosis diminished. Local control was 89% in tumors less than 6 cm3 and 52% when volumes were > or =6 cm3 (P = .0012). The likelihood of maintaining laryngeal function also varied with tumor volume: 89% for tumors less than 6 cm3 and 40% for tumors > or =6 cm3 (P = .00004). Pre-epiglottic space involvement by tumor of > or =25% was associated with a reduced chance of saving the larynx (P = .0076). Multivariate analyses revealed that only tumor volume independently altered these end points. CONCLUSION: Pretreatment CT measurements of tumor volume permits stratification of patients with supraglottic SCC treated with RT alone (which allows preservation of laryngeal function) into groups in which local control is more likely and less likely. Pre-epiglottic space spread is not a contraindication to using RT as the primary treatment for supraglottic SCC.

Carcinoma, Squamous Cell↗
PubMed1999

Health related quality of life in a population sample with arthritis.

OBJECTIVE: To determine the prevalence and health related quality of life of a community sample of people with arthritis and compare it with persons with other chronic diseases and the healthy population in South Australia. METHODS: A representative population survey by trained interviewers in autumn 1995 using a multi-stage, systematic, clustered area sample of 4200 urban and country households. There were 3001 (73.6%) respondents aged 15 or over. Subjects were asked, "Have you ever been told by a doctor that you have arthritis?" and "What type?", in addition to the Medical Outcome Survey Short Form-36 (SF-36) health status survey. RESULTS: Medically confirmed arthritis was self-reported in 666 (22.1%) as osteoarthritis (OA) (8.6%), rheumatoid arthritis (RA) (4.0%), and other, or unspecified arthritis (9.6%). People with arthritis were more likely to be female, aged, and of lower socioeonomic status. SF-36 scores were compared to nonarthritic subjects and adjusted for differences in age, sex, and occupational status. Scores were significantly lower for respondents with arthritis, compared with the rest of the population across all subscales of the SF-36 (p<0.05). This was most marked in the subscales measuring physical function and pain. CONCLUSION: Self-reported arthritis is common in the South Australian population, particularly in those aged over 65 years. Arthritis has a major impact on the health related quality of life in the community setting.

Adolescent↗