Prevalence of Chlamydia trachomatis in young men in north west London

BACKGROUND

Chlamydia trachomatis is the most common, treatable, bacterial sexually transmitted infection in England and Wales. Among men, chlamydial infection is an important cause of non-gonococcal urethritis, epididymitis, and proctitis. The case for wider screening among women has been accepted by an expert advisory group. In the absence of estimates of the prevalence of infection in men, its potential impact at the population level is difficult to assess.

OBJECTIVE

To estimate the prevalence of Chlamydia trachomatis in young men in clinic and community based samples in north west London.

METHOD

Cross sectional survey in healthcare centres and general practices in north west London. 1002 males aged 18-35 years, living in north west London, were recruited by staff in occupational health departments, general practices, student health services, and a "well man" clinic and by postal recruitment in four GP practices. The men were tested for C trachomatis using the ligase chain reaction assay on urine samples. The main outcome measure was prevalence of C trachomatis infection in men aged 18-35 years.

RESULTS

The overall response rate was 51%. Prevalence of confirmed infection was 1.9% (95% CI: 1.14% to 2.96%) in all men. Best estimated minimum prevalence of infection was 1% (95% CI: 0.58% to 1.50%). Estimated prevalence was highest among men aged over 30 years.

CONCLUSIONS

The estimated prevalence among men is commensurate with that described for female populations in London. The results suggest that recruitment of men to screening programmes would be difficult. However, a higher proportion of chlamydial infection may be detected in men than in women by existing approaches to control through genitourinary medicine clinic based case finding and contact tracing. Screening of young women and the contact tracing of the male partners of positive females may be an efficient approach to improving chlamydia control.

Prevalence of sexual dysfunction in new heterosexual attenders at a central London genitourinary medicine clinic in 1998

OBJECTIVE

To determine the prevalence of sexual dysfunction and dissatisfaction (SD) among new heterosexual attendees at a central London genitourinary medicine (GUM) clinic.

METHODS

Consecutive new attendees seen by a single clinician were asked a probe question about SD in the previous year. A clinical interview followed a positive response to the probe question. Demographic information was obtained using standard clinic forms.

RESULTS

37% of 103 men and 20% of 100 women participants gave positive responses, and 24% of the men and 12% of the women wanted treatment for their problems.

CONCLUSIONS

Our results indicate a relatively high rate of SD in new GUM clinic attendees that is not currently being detected or managed. SD may lead to psychological problems, which can be reversed with appropriate treatment. The financial implications of such treatment are discussed.

Identifying alcohol-related harm in young drinkers: the role of accident and emergency departments

Data are presented from a screening study of ambulant attendees at two London Accident and Emergency (A&E) departments. Among young people (aged 16-24 years), 37.2% were drinking harmfully [an Alcohol-Use Disorders Identification Test (AUDIT) score of 8 or more]; 17.3% admitted to drinking alcohol in the 6 h prior to attendance; and 14.6% considered that their attendance was alcohol related. Young women were as likely as men to score 8 or over. This age group had nearly twice the odds of scoring highly on the AUDIT, compared to those over 25 years old, and were more likely to report that their attendance was alcohol related. Screening in A&E departments would identify considerable numbers of young people who might benefit from brief intervention, but the problems of doing so are acknowledged.

Incidence of gonorrhoea diagnosed in GUM clinics in South Thames (west) region

OBJECTIVES

To describe the incidence of gonorrhoea diagnosed in genitourinary medicine (GUM) clinics in South Thames (West) between 1995 and 1996, and how it changed among population subgroups.

SETTINGS AND SUBJECTS

Cases of uncomplicated and complicated gonorrhoea diagnosed at 13 GUM clinics in the former South Thames West (STW) Regional Health Authority that reported disaggregate data to the South Thames GUM Clinic Collaborative STD Surveillance Scheme.

METHODS

Annual incidence rates (per 100,000) of gonorrhoea diagnoses by sex, age group, ethnic group, area of residence, and year were calculated. Poisson regression models were used to calculate risk ratios (RR) to describe the key differences in the variation of gonorrhoea cases by these variables. Relative differences in the incidence of diagnosed gonorrhoea between 1995 and 1996 were investigated by including an interaction between year and the other variables (age group, sex, ethnic group, region) and testing whether any were significant using a likelihood ratio test.

RESULTS

Area of residence, sex, age group, and ethnic group were key predictors of the rates of diagnosed gonorrhoea. The risk ratio for gonorrhoea (after adjustment for the other variables) was: 13 times higher among blacks than the white population; twice as high in inner London compared with outer London; and three times lower in the "shire" region compared with outer London. The rate of diagnosed gonorrhoea was significantly higher in the black population in the shire region than the inner London white population. The rate of gonorrhoea diagnosed by GUM clinics from 1995 to 1996 almost doubled in the white population aged 15-44 years, from 16 cases per 100,000 to 30 cases per 100,000 (adjusted RR 2.0, 95% CI 1.6 to 2.4), whereas increased rates in the black and Asian/other ethnic groups were not statistically significant (adjusted RR 1.1, 95% CI 0.9 to 1.4; and 1.4, 95% CI 0.7 to 2.7 respectively).

CONCLUSION

The observed increase in gonorrhoea between 1995 and 1996 occurred mostly among heterosexual white men and women. Overall, the rates of gonorrhoea among young people, especially in the black population and in inner London represent a significant public health problem that may merit further targeted interventions, the effectiveness of which could be monitored through further development of routine surveillance data.

HIV prevalence and risk behaviour among female injecting drug users in London, 1990 to 1996

OBJECTIVE

To describe trends in HIV prevalence among female injecting drug users (IDU) in London between 1990 and 1996.

DESIGN

HIV prevalence and risk behaviour were measured yearly between 1990 and 1993, and in 1996, in point prevalence HIV surveys of IDU recruited from both drug-treatment and community-based settings within Greater London. Sample sizes were 173 in 1990, 111 in 1991, 128 in 1992, 146 in 1993 and 200 in 1996.

METHODS

Each survey used structured questionnaires and common sampling and interview strategies. Oral fluid specimens were collected for testing for antibodies to HIV (anti-HIV). Multiple logistic regression was used to assess the trend in HIV prevalence.

RESULTS

The percentage of female IDU testing positive for antibodies to HIV showed a marked decline over the study period, from 15.0% in 1990 to 1.0% in 1996 (P < 0.001). This trend was independent of all other variables examined. Each year, higher HIV prevalences were found among IDU recruited from community settings compared with treatment agencies.

CONCLUSIONS

These results concur with those of IDU recruited from treatment sites, although the yearly estimates in this study are higher. London benefits from low prevalence of HIV infection among IDU, coupled with behaviour change facilitated by early intervention. Continued surveillance of injectors recruited from both community and treatment settings is necessary in order properly to assess HIV prevalence among IDU.

Thermochemistry of Oxo Transfer from Coordinated Nitrite in the Dinitro(5,10,15,20-tetrakis(o-pivalamidophenyl)porphinato)iron(III) Anion

The thermochemistry of oxo transfer from coordinated nitrite in the dinitro(5,10,15,20-tetrakis(o-pivalamidophenyl)porphinato)iron(III) anion, ion-paired with the tetrapropylammonium ion, {[Fe(III)TpivPP(NO(2))(2)](-)Pr(4)N(+)}, has been evaluated in acetonitrile solution. This oxo-transfer half-reaction of {[Fe(III)TpivPP(NO(2))(2)](-)Pr(4)N(+)} has been assessed on the basis of the determination of the E(1/2) = +0.54 V vs SHE for the reversible [Fe(II/III)TpivPP(NO)(NO(2))](-)(/0) couple and the measurement of the formation constants for the association of NO and NO(2)(-) with the mononitroiron(III) porphyrin derivative. The formation constant for nitric oxide association, K(NO), has the value (1.21 +/- 0.08) x 10(3). The stability constant, K(2), for association of a second nitro ligand in 0.0100 M tetrapropylammonium perchlorate medium has been estimated as 2.18 x 10(3). The oxo-transfer half-reaction free energy, DeltaG degrees ((X/XO)), for addition of oxygen to [Fe(II)TpivPP(NO)(NO(2))](-) to form {[Fe(III)TpivPP(NO(2))(2)](-)Pr(4)N(+)} has been found to be -50 kJ/mol.

T-cell proliferative response to human papillomavirus type 16 peptides: relationship to cervical intraepithelial neoplasia

The incidence of human papillomavirus (HPV)-related cervical intraepithelial neoplasia (CIN) and cervical cancer is increased with immunodeficiency, but the role of immune response, including cell-mediated immunity, in disease prevention is not well understood. In this study, T-cell proliferative responses to six synthetic peptides with predicted immunogenic determinants from the HPV-16 E4, E6, E7, and L1 open reading frames were analyzed in 22 sexually active women with new-onset CIN and 65 sexually active women without cervical disease, characterized by cytology, colposcopy, and HPV testing. T-cell proliferative responses were demonstrated to all six HPV-16 peptides. Although not statistically significant, rates of reactivity to E6 (24-45) were higher among sexually active women without disease (26%) than among women with current CIN (7%), as was the overall number of peptides stimulating a response. Women with CIN may not respond to selected HPV antigens as well as women without disease do.

The hepatitis B virus-encoded transcriptional trans-activator hbx appears to be a novel protein serine/threonine kinase

To study the functional mechanism of the hepatitis B virus (HBV) X (hbx) gene product, we have expressed the hbx protein in E. coli and purified it by HPLC. The purified hbx protein was shown to be active in transactivating transcription directed by the LTR sequence of HIV-1. The hbx protein was found to have an intrinsic serine/threonine protein kinase activity. The hbx protein was detected in hepatitis B virions, and tryptic phosphopeptide maps of the hbx protein phosphorylated in the virion and of the in vitro phosphorylated bacterially expressed hbx protein were similar. Inactivation of the hbx protein by heat, protein-denaturing agents, or an ATP affinity analog, p-fluorosulfonylbenzoyl 5'-adenosine, resulted in loss of both protein kinase activity and trans-activation activity. These results suggest that the HBV-encoded trans-activator hbx is a novel protein kinase.

M protein (M1) of influenza virus: antigenic analysis and intracellular localization with monoclonal antibodies

A panel of 16 monoclonal antibodies recognizing M protein (M1) of influenza virus was generated. Competition analyses resulted in localization of 14 monoclonal antibodies to three antigenic sites. Three monoclonal antibodies localized to site 1B recognized a peptide synthesized to M1 (residues 220 to 236) with enzyme-linked immunosorbent assay titers equivalent to or greater than that seen with purified M1; therefore, site 1B is located near the C terminus of M1. Sites 2 and 3 localize to the N-terminal half of M1. Antigenic variation of M proteins was seen when the monoclonal antibodies were tested against 14 strains of type A influenza viruses. Several monoclonal antibodies showed specific recognition of A/PR/8/34 and A/USSR/90/77 M proteins and little or no reactivity for all other strains tested. Immunofluorescence analysis with the monoclonal antibodies showed migration of M protein to the nucleus during the replicative cycle and demonstrated association of M protein with actin filaments in the cytoplasm. Use of a vaccinia virus recombinant containing the M-protein gene demonstrated migration of M protein to the nucleus in the absence of synthesis of gene products from other influenza virus RNA segments.

Expression of immunogenic epitopes of hepatitis B surface antigen with hybrid flagellin proteins by a vaccine strain of Salmonella

A nonvirulent Salmonella dublin flagellin-negative, aromatic-dependent live vaccine strain has been used to express hepatitis B virus surface antigen epitopes in an immunogenic form. The envelope proteins of the virion are encoded by the S gene, which contains the pre-S1, pre-S2, and S coding regions. Synthetic oligonucleotides corresponding to amino acid residues S-(122-137) and pre-S2-(120-145) were inserted in-frame into the hypervariable region of a cloned Salmonella flagellin gene, and the recombinant plasmids were introduced into a flagellin-negative aroA mutant live vaccine strain of S. dublin, SL5928. The flagellin gene was expressed in bacteria carrying the plasmids as detected by immunoblotting with anti-flagellin (H1-d) serum. Both the S and pre-S2 epitopes were detected in bacteria carrying the relevant plasmid by immunoblotting with anti-HBs (antibody to hepatitis B virus surface antigen) and anti-peptide antisera. Animals immunized intramuscularly or orally with the live recombinant bacteria developed antibodies specific to these hepatitis B virus epitopes as detected by ELISA.

Patients' knowledge concerning their medications on discharge from hospital

Fifty patients were interviewed, on discharge from hospital, about their medications. Nine (18%) patients did not know, and a further four (8%) had inappropriate beliefs about why they were taking at least one of their discharge medications. Very few patients knew of significant side-effects which they might expect, or precautions which they should take, and over half did not know how long they were to continue taking their medicines. A small proportion was unable to read the bottle or open the container. Thus, even patients who, by virtue of an in-patient stay, have had a prolonged opportunity for education regarding their medicines have very little knowledge of their medicines upon discharge from hospital.

Premedication with lorazepam before bone marrow biopsy

Fifty patients were randomised in a double blind placebo controlled study to examine the influence of lorazepam (4 mg orally) before bone marrow aspiration and trephine biopsy. Assessment was made by a visual analogue linear pain scale compiled after the procedure and again 24 hours later. There was no difference in the pain recalled immediately after the procedure between the two groups, but the next day the patients who had received lorazepam showed amnesia with a 60% (p less than 0.01) reduction in the pain scale; 36% of the patients in this group had no recall of the procedure at all. There was no amnesic effect in the group taking placebo. Side effects were few, and it is concluded that lorazepam is a useful premedication agent before bone marrow biopsy.

Factors modulating the secretion of thyrotropin and other hormones of the thyroid axis

The first portion of this paper is devoted to an overview of the normal function of the hypothalamo-pituitary-thyroid axis. This section emphasizes areas of current research interest and it identifies several sites and mechanisms that are potentially important interfaces with toxins or toxic mechanisms. We then describe an in vitro technique for the continuous superfusion of enzymatically dispersed pituitary cells; this approach is particularly valuable in studying the dynamics of the TSH responses to the factors known (or suspected) to regulate TSH secretion in vivo. Using this technique, we have found that 10(-5)M prostaglandin (PG)I2 stimulates TSH secretion without altering the response to TRH (10(-8)M), and that this stimulation is not due to its rapid conversion to 6-keto PGF1 alpha. In contrast PGs of the E series (PGE1 and PGE2, 10(-5)M) increase responsiveness to TRH but have no effect alone. We found no effects of any of the other prostanoids tested (PGs A2, B2, F1 alpha, F2 alpha, thromboxanes A2 and B2, and the endoperoxide analog, U-44069. Somatostain (10(-9)M inhibits TRH-induced TSH secretion, but does not alter the responsiveness to PGI2. These findings suggest that somatostatin blocks TSH secretion at a point that is functionally prior to the involvement of the PGs, and perhaps does so by blocking synthesis or limiting availability of selected PGs.

The role of noradrenaline, dopamine and 5-hydroxytryptamine in the hyperactivity response resulting from the administration of tranylcypramine to rats pretreated with lithium or rubidium

1. The administration of 15 mg/kg tranylcypromine sulphate (Tc) to rats which have been given lithium chloride (LiCl) in the diet (30 mmol/kg dry food) for 14 days produces hyperactivity within 4 hrs, and this lasts for at least 4 further hours. 2. If LiCl is replaced by rubidium chloride (RbCl) at the same dose, the hyperactivity following Tc is increased and it appears within 2 hrs. 3. 5-Hydroxytryptamine (5HT) accumulation after a monoamine oxidase inhibitor (Tc) is increased 46% and 85% respectively above control values by LiCl and RbCl administration. 4. The hyperactivity produced by the above combinations is inhibited by alpha-methyl-p-tyrosine (alphampt). The inhibition is more effective following LiCl than RbCl treatment. 5. After sodium chloride (NaCl) and LiCl treatment, but not after RbCl treatment, the combination of alphampt and Tc produced rat brain concentrations of dopamine (DA) significantly below control values. 6. The smaller increase of brain noradrenaline (NA) after Tc and RbCl suggests that a lower percentage of NA is being metabolised by MAO. The greater decrease of NA after giving alphampt to RbCl and LiCl treated rats suggests an increased "turnover" rate of Na. 7. The hyperactivity syndrome seen in rats after the administration of LiCl or RbCl and Tc is dependent upon both 5HT and dopamine mechanisms.