PubMed Health⌕ Search

Biomedical subjects

K Fenton

Publications and source records attributed to K Fenton.

17 recordsLinked to original sources

Application of a noninvasive oral fluid test for detection of treponemal IgG in a predominantly HIV-infected population.

The performance of a time-resolved fluorescence immunoassay (TRFIA) for detection of treponemal IgG from oral fluid specimens has been assessed in a predominantly HIV-infected population. Serological investigation is the method of choice for confirming clinical suspicion of syphilis; however, in the primary stage of disease, direct detection of treponemes in lesion fluid or Treponema pallidum DNA is recommended because of the reduced sensitivity of serological tests. There may be occasions when blood for serological investigation is difficult to obtain due to individual patient preference or logistical necessity to improve participation in screening initiatives, particularly in outreach situations. Collection of oral fluid for detection of treponemal antibody may prove an attractive alternative and, with this in mind, an oral fluid assay for detection of treponemal IgG was developed. Time-resolved fluorescence was used to detect treponemal IgG extracted from commercially available oral fluid collection devices. Paired serum and saliva samples were obtained from 210 individuals, 101 of whom were diagnosed with syphilis on the grounds of medical examination confirmed by serological testing. Oral fluid specimens from 14 subjects were rejected because they contained insufficient control antibody or were inhibitory. The population tested was predominantly men who have sex with men, many of whom were HIV infected. The overall sensitivity and specificity of the oral fluid assay was 95.8 and 86.1%, respectively, based on the 5th percentile of the positive results, and 93.7 and 91.1%, respectively, based on a cutoff derived by mixture model analysis. For individuals with primary syphilis, the optimum sensitivity of the oral fluid assay was 87.5%, whereas in those with disease classified as secondary syphilis and early latent syphilis, the sensitivity of the oral fluid assay was 100 and 94.7%, respectively. The oral fluid assay is a useful alternative to serological testing in certain situations, and further development of this technology to enable detection of treponemal IgM should increase its sensitivity for detecting cases of primary syphilis.

Adult↗

The prevalence of proline iminopeptidase negative Neisseria gonorrhoeae throughout England and Wales.

BACKGROUND: The accurate laboratory identification of Neisseria gonorrhoeae is an essential element of the diagnosis of gonorrhoea and is particularly important for medicolegal cases. The detection of proline iminopeptidase (Pip) activity is widely used as a marker for gonococci, although Pip negative N gonorrhoeae isolates have been shown to generate false negative identifications when using biochemical kits. This study aimed to determine the frequency of Pip negative gonococci in England and Wales. METHODS: A total of 2055 isolates were collected from consecutive patients attending 26 genitourinary medicine centres as part of the Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP). Upon receipt the identity of all isolates was confirmed using N gonorrhoeae specific monoclonal antibodies and the Pip status was determined using the Gonochek II kit. RESULTS: The overall prevalence of Pip negative isolates was found to be 4.33%. Significant geographical variation was observed between isolates from centres outside London (p< or =0.001). Variation was also observed within London between the nine different clinics submitting isolates (p = 0.025). There was also a higher frequency of these isolates among men who have sex with men (p< or =0.001), which may account for geographical variations. CONCLUSION: Pip negative N gonorrhoeae isolates are a very serious cause for concern as currently all biochemical test kits available within the United Kingdom require the presence of the Pip enzyme for an unambiguous identification of this pathogen. Raising awareness of the current prevalence of Pip negative N gonorrhoeae isolates is critical for the successful control of gonorrhoea.

Aminopeptidases↗

Who pays for sex? An analysis of the increasing prevalence of female commercial sex contacts among men in Britain.

BACKGROUND: In the United Kingdom the incidence of sexually transmitted infections (STI) and risky sexual behaviours is increasing. The role of commercial sex in this trend is poorly understood. Little is known about the men who pay for sex. We examined the epidemiology of female commercial sex contacts reported by men in 1990 and 2000. METHODS: National probability sample surveys of sexual attitudes and lifestyles (Natsal) of men aged 16-44 resident in Britain in 1990 (n = 6000) and 2000 (n = 4762). RESULTS: The proportion of men who reported paying women for sex in the previous 5 years increased from 2.0% (95% CI 1.6 to 2.5) in 1990 to 4.2% in 2000 (95% CI 3.6 to 4.9). In both surveys, paying for sex was more frequent in men aged between 25 years and 34 years, who were never or previously married, and who lived in London. There was no association with ethnicity, social class, homosexual contact, or injecting drug use. Men who paid for sex were more likely to report 10 or more sexual partners in the previous 5 years; only a minority of their lifetime sexual partners (19.3%) were commercial. They were more likely to meet partners abroad and to report previous STI. Only 15% reported having had an HIV test. CONCLUSION: The proportion of men who reported paying for heterosexual sex has increased, and these men have multiple commercial and non-commercial partners. Their higher rates of STI and low level of HIV testing suggest the need for prevention interventions for clients as well as sex workers.

Adolescent↗

An agenda for future research on HIV and sexual behaviour among African migrant communities in the UK.

The epidemiology of the recent rise in HIV cases in Britain highlights the need for more research among the heterosexual African migrant population. New research should not, however, only extend the limited number of studies that describe observable patterns in sexual health but should also seek to determine their underlying social causation. To achieve this, both methodological and ontological shifts are necessary in the existing research paradigm; we advocate that a broad range of qualitative techniques be deployed both to uncover the empirical details of specifically African sexual behaviours and to highlight and explore the 'relational' nature of sexual decision-making. Rather than fixing on individuals, analysis must situate them within the broader discursive and material frames that structure the boundaries of decision-making. In addition, researchers need to utilise the parallel literature on the social embeddedness of HIV in Africa to inform analysis of the British context. It would then be possible to address the crucial question of whether the social conditions known to cause high-risk behaviours and facilitate transmission in Africa persist, or are transformed, after migration to the UK. A key, and neglected, dimension of this is the role of spatial context in relational sexual decision-making and the constitution of social relationships in particular arenas. This needs further thought, particularly in relation to domestic space and gender identities. We believe that the research agenda proposed herein has much to contribute to interventions and service provision. Nevertheless, we are mindful of the need for self-reflexivity about our role in the production of powerful knowledges about sex. Our final proposal is that researchers seek ways to work with, not on, African communities in order to facilitate their own informed management of sexual health.

Humans↗

Provision of chlamydia testing in a nationwide service offering termination of pregnancy: with data capture to monitor prevalence of infection.

OBJECTIVES: To establish a methodology by which all women attending for termination of pregnancy (TOP) at British Pregnancy Advisory Service (BPAS) branches may be approached to participate in Chlamydia trachomatis screening. To examine the feasibility of monitoring C trachomatis prevalence and the impact of charging for screening on the uptake rate in this population. METHODS: Patients attending for TOP at participating BPAS branches were offered a test for chlamydia infection and asked to complete a questionnaire. Urine samples from participants were tested using a nucleic acid amplification test (NAAT). RESULTS: 1001 women provided a urine sample, a 77% response rate among those participating in the study. Factors significantly associated with taking up chlamydia screening included symptoms, previous TOP, parity, and no previous chlamydial test. Overall prevalence of genital chlamydial infection was 7.5%, with highest age specific prevalences occurring among attendees aged 20-24 years (11.5%) and under 20 years (10.8%). In univariate analysis, chlamydia positivity was significantly associated with respondent age and previous diagnosis with chlamydia. Only 35% of women who had the screening test would have done so had they been asked to pay the pound 20 clinical, administrative, and laboratory costs of the examination. CONCLUSIONS: We have demonstrated the feasibility of routine chlamydia screening and the potential for prospective prevalence monitoring across the nationwide BPAS service. In most cases the chlamydia result was available within the clinical contact period for the TOP. Charging patients directly for the test could reduce uptake of chlamydia screening to levels unsatisfactory for both the public health and prevalence monitoring purposes.

Abortion, Induced↗

Effect of computer-assisted self-interviews on reporting of sexual HIV risk behaviours in a general population sample: a methodological experiment.

OBJECTIVES: To develop methods to maximize the accuracy of reporting HIV risk behaviours in a general population survey. We assessed the feasibility of using a computer-assisted self-completion interview (CASI) in comparison with pen-and-paper self-completion interview (PAPI). DESIGN: A probability sample survey of residents aged 16-44 years in Britain, with alternate assignment of addresses to interview by CASI (462) or PAPI (439). METHODS: Personal interviews exploring demographic and sexual behaviour variables. Principal outcome measures were the impact of CASI in relation to PAPI on data quality and rates of reporting a range of behaviours. RESULTS: A total of 901 interviews were completed; 829 individuals were eligible for and accepted the self-completion module. Internal consistency of data items was greater with CASI than PAPI and item non-response was lower. Overall, there was no significant difference in rates of reporting between CASI and PAPI. The main effect for CASI compared with PAPI in a generalized estimating equation (GEE) analysis was an OR (95% CI) of 1.04 (0.92-1.17). Variables were also examined individually, including homosexual partnership (adjusted OR 1.26 95%, CI 0.69-2.29), payment for sex (adjusted OR 0.68 95% CI 0.29-1.59), masturbation (adjusted OR 0.89 95% CI 0.66 1.22) and five or more partners in the past 5 years (OR 0.85 95% CI 0.61 -1.19). CONCLUSION: We found no evidence of a consistent effect of CASI on rates of reporting sexual HIV risk behaviours in this sample. CASI resulted in improvement in internal consistency and a reduction in missed questions.

Adolescent↗

Assessing the impact of national anti-HIV sexual health campaigns: trends in the transmission of HIV and other sexually transmitted infections in England.

OBJECTIVE: To assess the impact of the sexual component of AIDS and HIV campaigns on transmission of HIV and other sexually transmitted infections (STIs). DESIGN: Comparison of time series data. SETTING: England, 1971-1999. OUTCOME MEASURES: HIV transmission and diagnoses among men who have sex with men (MSMs), rates of attendances and specific STI diagnoses (per 100 000 total population) at genitourinary medicine (GUM) clinics. RESULTS: Awareness of AIDS and campaigns in 1983-4 among homosexual men coincided with substantial declines in transmission of HIV and diagnoses of syphilis among MSMs. During general population campaigns in 1986-7 new GUM clinic attendances requiring treatment fell by 117/10(5) in men and 42/10(5) in women. Rates for gonorrhoea fell by 81/10(5) and 43/10(5) and genital herpes by 6/10(5) and 4/10(5), respectively. Previous rises in genital wart rates were interrupted, while rates of attendances not requiring treatment (the "worried well") increased by 47/10(5) and 58/10(5) for men and women, respectively. Since 1987 diagnoses of HIV among MSMs have not declined, averaging 1300-1400 annually. Following a period of unchanging rates there have been substantial increases in GUM attendances requiring treatment, notably for gonorrhoea, syphilis, and viral STIs since 1995. CONCLUSIONS: Self help initiatives and awareness among homosexual men in 1983-4 contributed significantly to a fall in HIV transmission among MSMs, and the general campaigns of 1986-7 were associated with similar effects on all STI transmission. Both effects seem to have occurred through changing sexual behaviour, and probably contributed to the UK's low national HIV prevalence. Bacterial STI incidence has increased significantly since 1995 and there is no evidence that recent prevention initiatives have reduced HIV transmission among MSMs, hence sexual health initiatives need to be comprehensively reinvigorated in England.

Condylomata Acuminata↗

Europe-wide surveillance for sexually transmitted infections: a timely and appropriate intervention.

Sexually transmitted infections (STIs), including HIV, pose a significant threat to the health and wellbeing of Europeans and require concerted and sustained intervention. Over the past decade, the number of reported cases of STIs, including antimicrobial resistant Neisseria gonorrhoeae, has increased appreciably, and outbreaks of syphilis have recently been reported in many Member states of the European Union (EU). Young people, homosexual men, and those with poor access to health care (including preventive and educational services) seem to be particularly affected, with increased travel and migration, high risk sexual behaviours, and a deterioration of public health responses to STI control (for example, partner notification) being key driving factors. Many of these demographic and behavioural trends are similar across EU states, as is the desire to develop and implement effective STI prevention and control programmes.

European Union↗

Lead effects on offspring depend on when mouse mothers were exposed to lead.

Target mice were nursed by mothers given lead starting (1) when target mice were born; (2) after conception of target mice, or (3) during the mothers' own pre-weaning age. These target mice are called, respectively, POSTNATAL, GESTATIONAL, and PRE-MATING. Compared to developments in control mice, postnatal lead slowed brain weight development, lowered asymptotic brain weight, decreased DNA per brain somewhat, but had no effect on protein per brain. Gestational lead similarly slowed brain weight development, lowered asymptotic brain weight, greatly decreased DNA per brain, but had no effect on protein per brain. In contrast, pre-mating lead significantly increased brain weight and protein per brain and lowered DNA per brain substantially. These effects of pre-mating lead on brain weight and protein per brain could be due to the effects of lead on developing maternal reproductive systems or to lead's presence during the rarely studied ovulation-to-fertilization period.

Animals↗

Behavioural intervention trials for HIV/STD prevention in schools: are they feasible?

OBJECTIVE: To assess the feasibility of conducting a large randomised controlled trial (RCT) of peer led intervention in schools to reduce the risk of HIV/STD and promote sexual health. METHODS: Four secondary schools in Greater London were randomly assigned to receive peer led intervention (two experimental schools) or to act as control schools. In the experimental schools, trained volunteers aged 16-17 years (year 12) delivered the peer led intervention to 13-14 year old pupils (year 9). In the control schools, year 9 pupils received the usual teacher led sex education. Questionnaire data collected from year 9 pupils at baseline included views on the quality of sex education/intervention received, and knowledge and attitudes about HIV/AIDS and other sexual matters. Focus groups were also conducted with peer educators and year 9 pupils. Data on the process of delivering sex education/intervention and on attitudes to the RCT were collected for each of the schools. Analysis focused on the acceptability of a randomised trial to schools, parents, and pupils. RESULTS: Nearly 500 parents were informed about the research and invited to examine the study questionnaire; only nine raised questions and only one pupil was withdrawn from the study. Questionnaire completion rates were around 90% in all schools. At baseline, the majority of year 9 pupils wanted more information about a wide range of sexual matters. Focus group work indicated considerable enthusiasm for peer led education, among peer educators and year 9 pupils. Class discipline was the most frequently noted problem with the delivery of the peer led intervention. CONCLUSION: Evaluation of a peer led behavioural intervention through an RCT can be acceptable to schools, pupils, and parents and is feasible in practice. In general, pupils who received the peer led intervention responded more positively than those in control schools. A large RCT of the long term (5-7 year) effects of this novel intervention on sexual health outcomes is now under way.

Adolescent↗

Lead acetate delays rapid postnatal mouse brain and body growth.

Starting at parturition and continuing until weaning, mothers of five mouse litters received tap water while five others had 10 mg PbAc/ml in their drinking water. The offspring receiving lead from the mothers had significantly lower body weights after the first days of receiving lead; their slowed body growth led to a 2-day delay of onset (usually at 16-18 days) of their last rapid body growth stage. They also had significantly smaller brain weights between age 14 days and weaning (23 days). The onset of rapid brain growth was delayed from its usual onset at 16-18 days to about 22-23 days before rising to about the same value as the control mice at 26 days. Thus, the initial effect on brain growth is decidedly greater than on body growth, though brain weight later reaches close to the control value.

Animals↗