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M Prins

Publications and source records attributed to M Prins.

At least 73 records · Page 4Linked to original sources
PubMed1996

Summary of track C: epidemiology and public health.

AIM: To review Track C on epidemiology and public health. DESCRIPTIVE EPIDEMIOLOGY: Recent trends in the descriptive epidemiology are reported, for example, the rapid spread of HIV in certain Asian countries and the more precise insights in the spread thanks to subtyping of HIV-1 (and HIV-2). TRANSMISSION: There is now ample evidence that sexually transmitted diseases enhance the rate of transmission. Viral load in the plasma of the mother is highly predictive for perinatal transmission. PROGRESSION: Natural history studies have shown that true non-progressors are probably rare. Preliminary evidence indicates that the progression rate to AIDS and death does not differ by HIV-1 subtype. Some genetic factors are associated with the rate of disease progression and a few with susceptibility to HIV infection. INTERVENTIONS AND PREVENTION: Needle-exchange programmes as an intervention measure for injecting drug users were hotly debated and so were HIV (home) testing and counselling. Successes in prevention were reported from Thailand and Uganda, and also from small scale programmes.

Female↗
PubMed1995

Transport of a hydrophilic compound into the cerebrospinal fluid during experimental allergic encephalomyelitis and after lipopolysaccharide administration.

PURPOSE: The transport of the hydrophilic model compound sodium fluorescein into the cerebrospinal fluid (CSF) of rats was studied during experimental allergic encephalomyelitis (EAE), as a model for local central nervous system (CNS) inflammatory disease, and after a single injection of a pyrogenic dose of lipopolysaccharide (LPS), as a model for a general inflammation. METHODS: Transport of sodium fluorescein was measured by means of serial CSF and plasma sampling. Transport of this hydrophilic model compound was studied in Lewis rats suffering from EAA and three hours after LPS administration in male Wistar rats. RESULTS: During acute EAE, sodium fluorescein concentrations in the CSF increased twofold compared to control animals, whereas plasma kinetics were comparable within both groups. After i.v. LPS administration, however, plasma as well as CSF kinetic parameters of sodium fluorescein concentration were significantly changed from those seen in control animals. Transport of sodium fluorescein from plasma into the CSF was calculated as the ratio Area Under the Curve (AUC)CSF/AUCPLASMA. During acute EAE this ratio increased 2-fold compared to control animals, whereas after i.v. LPS administration it was not significantly different from the one obtained in control animals. CONCLUSIONS: These results suggest an opening of the blood-brain barrier (BBB) during a cerebral inflammatory response, like acute EAE, but not after LPS administration.

Animals↗
PubMed1995

Lower prevalence and incidence of HIV-1 syncytium-inducing phenotype among injecting drug users compared with homosexual men.

OBJECTIVE: To study the prevalence, incidence and predictive value for progression to AIDS of the HIV-1 syncytium-inducing (SI) phenotype in HIV-infected injecting drug users (IDU) compared with HIV-infected homosexual men. DESIGN: Two prospective cohort studies on HIV-1 infection among IDU and homosexual men. METHODS: HIV-infected IDU (n = 225) and homosexual men (n = 366) without AIDS were studied from March 1989 through December 1993. Data on laboratory markers, including the presence of SI variants, demographics, behavioural characteristics and clinical events were collected at every visit. RESULTS: At baseline, SI variants were detected in 4% of IDU and 17% of homosexual men. During the study period 18 IDU and 68 homosexual men switched from non-SI to SI phenotype (4-year cumulative incidence, 14.6 and 28.4%, respectively) before AIDS diagnosis. Among participants with a documented date of HIV infection the cumulative incidence of SI was lower among IDU than homosexual men (4-year cumulative incidence, 6.2 and 20.7%, respectively). At AIDS diagnosis, 21% of all AIDS cases among IDU had the SI phenotype compared with 54% among homosexual men. In both risk groups an accelerated CD4 decline was found after the non-SI-to-SI switch. The SI phenotype appeared to be a predictor of AIDS (multivariate relative hazard, 5.33), independent of CD4 cell count and p24 antigen at baseline. In the multivariate time-dependent analysis, the relative hazard of SI phenotype decreased considerably, which is consistent with the hypothesis that the effect of SI phenotype on progression to AIDS is mediated by CD4 cell count. CONCLUSION: The SI phenotype is associated with accelerated CD4 decline and progression to AIDS in both risk groups. The remarkable lower prevalence and incidence of the SI phenotype among IDU may implicate a difference in pathogenesis and natural history of HIV infection linked to transmission group.

Adult↗
PubMed1995

Detection of Chlamydia trachomatis infection in urine samples from men and women by ligase chain reaction.

The suitability of urine specimens from women and men for the detection of Chlamydia trachomatis infection by a ligase chain reaction (LCR)-based assay with plasmid primers was examined with a group of patients attending a sexually transmitted disease clinic in Amsterdam, The Netherlands. Cervical specimens from 15 of 237 (6.3%) women tested positive for C. trachomatis by cell culture. Of the 25 (10.5%) female urine samples that tested positive by the plasmid-LCR assay, 13 were obtained from cervical culture-positive women. Nine of the 12 plasmid-LCR-positive urine samples from cervical culture-negative women were confirmed to be positive by a second LCR assay with primers based on chromosomal DNA. Urethral specimens from 24 of 258 (9.3%) men were positive for C. trachomatis infection by cell culture. Of the 25 (9.7%) urine samples that tested positive by plasmid-LCR, 20 were from culture-positive men. All five of the LCR-positive urine samples from culture-negative men were confirmed to be positive by the LCR with chromosomal DNA primers. Relative to cell culture, testing by plasmid-LCR analysis of male urine samples had a sensitivity of 83.3% and a specificity of 97.9%; after resolution of discordant samples, these values were 86.2 and 100%, respectively. In the study with women, the sensitivities of plasmid-LCR analysis of cervical and urine specimens in comparison with cervical cell culture were 93.3 and 86.7%, respectively. After resolution of discrepant samples, the sensitivities of the plasmid-LCR test for cervical swabs and female urine samples were 96.3 and 92.6%, respectively. These results indicate that the plasmid-LCR-based assay is a very reliable, sensitive, convenient test for the detection of C. trachomatis infection in female and male urine specimens.

Bacteriological Techniques↗
PubMed1994

A prospective study of antibody responses to defined epitopes of human papillomavirus (HPV) type 16 in relationship to genital and anorectal presence of HPV DNA.

The aim of this study was to investigate whether antibody responses against synthetic peptides derived from genital human papillomavirus (HPV) proteins are associated with laboratory-proven genital and anorectal HPV infection. In this study, 158 heterosexual patients (110 women and 48 men) were followed prospectively. At each visit we collected serum samples as well as specimens from several sites in the anogenital area for detection of HPV type 6/11 (HPV-6/11), -16, -18, and -33 DNAs by PCR. Immunoglobulin A (IgA) and IgG responses against disrupted bovine papilloma virions and eight different synthetic peptides derived from HPV-6/11, -16, and -18 were determined for serum samples from the first and the last visits. The subjects attended the Municipal Sexually Transmitted Disease Clinic in Amsterdam, The Netherlands, two to seven times (mean, four times) at approximately 4-month intervals. Women were monitored over a period of 155 person-years, and men were monitored over 65 person-years. The magnitudes of the IgA responses against HPV-16 late protein epitopes L1:13, L1:31, and L2:49 were significantly higher in the sera from the last visit among the currently HPV DNA-positive participants than in HPV DNA-negative persons (P = 0.02). When the persons positive for any HPV type at any time during the follow-up period were compared with those who were negative at all times during the follow-up period, we also found a significant elevation of IgA responses against L1:31 and L2:49 (P = 0.04 and 0.01, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Regional distribution and incidence of human papillomavirus infections among heterosexual men and women with multiple sexual partners: a prospective study.

OBJECTIVE: To assess prevalence, incidence and potential risk factors of human papillomavirus (HPV) infection among heterosexual men and women with multiple partners and to identify niches of HPV-infection. DESIGN: A prospective study of heterosexual men and women with multiple partners attending an STD clinic as participants in a study on HIV from May 1988 until January 1991. Routine STD examination and physical examination using colposcopy were performed, interviews with standardised questionnaires were administered. Specimens for HPV DNA detection by polymerase chain reaction were collected from multiple sites of the genital, anorectal and oral regions. In women cervical cytology was performed. SETTING: The STD Clinic of the Municipal Health Service of Amsterdam. PARTICIPANTS: 162 women and 85 men entered the study, 110 women and 48 men were followed up. RESULTS: At entry of the study 37 (23%) women and 24 (28%) men were found positive for HPV DNA at any site. Only in one woman was oral presence of HPV DNA found during follow-up. Abnormal cervical cytology was observed in four women. In multivariate analysis, diagnosis of condylomata [odds ratio (OR) 5.61, 95% confidence interval (CI) 1.86 to 16.90)], reporting genital dermatological abnormalities (OR 3.72, 95% CI 1.38 to 9.99) and age (OR per year 0.93, 95% CI 0.88 to 0.99) predicted independently the presence of HPV DNA in women at entry of the study. In women 59 of the 99 (60%) HPV infections were observed in the genital region and 40% in the anorectal region: in men these figures were 65% and 35%, respectively. The incidence of HPV infection was 47.1 and 50.5 per 100 person-years for women and men respectively. At least 20/99 (20%) infections in women were intermediate or long persistent and only 3/48 (6%) HPV infections in men (P = 0.03). No risk factor for persistency could be determined, either in women or in men. CONCLUSIONS: HPV infection was found to be a multicentric genital and/or anorectal event both in women and men. The oral presence of HPV DNA was detected only once in one of the participants. In women persistent HPV infection was more common than in men. Independent predictors for presence of HPV DNA in women were diagnosis of condylomata acuminata, reporting genital dermatologic abnormalities and age. Incidence of HPV infection in women turned out to be 47.1 infections per 100 person-years and for men 50.5 per 100 person-years.

Adult↗
PubMed1994

Determinants of penicillinase producing Neisseria gonorrhoeae infections in heterosexuals in Amsterdam.

BACKGROUND AND OBJECTIVES: At the STD clinic of the Municipal Health Service in Amsterdam, the annual number of infections with penicillinase-producing Neisseria gonorrhoeae (PPNG) strains remained relatively stable from 1983 until 1990, while the number of non-PPNG infections declined dramatically. To investigate the PPNG and non-PPNG epidemic, a cross sectional study was conducted in 1989 and 1990. The purpose of this study was to assess determinants of PPNG infections among heterosexuals diagnosed with gonorrhoeae. METHODS: In addition to routinely collected data in new consultations for STDs, information on alcohol use, drug use and sexual behaviour was obtained from patients diagnosed with gonorrhoea. The diagnosis of gonorrhoea was based on a positive culture and isolates were screened for PPNG. Logistic regression analysis was used to assess independent predictors of PPNG infection. RESULTS: Additional information was available of 328 women and 995 heterosexual men diagnosed with gonorrhoea. PPNG was diagnosed in 86/328 (26%) women and in 329/995 (33%) men. Logistic regression analysis identified a Central/South American nationality (odds ratio(OR) = 2.46) and older age (OR = 1.04 per year) as positively associated with PPNG infection in female patients. An inverse relation was found with use of hard drugs (OR = 0.29). Among men diagnosed with gonorrhoea, sexual contacts with window prostitutes (mainly women from Central/South America) (OR = 1.98) and a foreign nationality (OR = 1.78) were positively associated with PPNG infection, and sexual contact with drug using prostitutes (OR = 0.47) inversely. CONCLUSIONS: PPNG infections were especially common among Central and South American window prostitutes and their clients, but not among hard-drug addicted prostitutes and their clients. Since window prostitutes originating from Central and South American countries are transient in Amsterdam, prevention activities targeted at these prostitutes and their clients should be continued to limit the spread of PPNG and other STDs within these groups.

Adult↗
PubMed1994

Low molecular weight heparin: a critical analysis of clinical trials.

LMWHs are an important new class of antithrombotic agents. They differ from UFH in having relatively more anti-Xa activity, greater bioavailability at low doses, longer half-life, and more predictable anticoagulant response when administered in fixed doses. These properties allow LMWHs to be administered QD or at most BID and without laboratory monitoring. The incidence of heparin-induced thrombocytopenia also appears to be lower with an LMWH than with heparin. Given their favorable pharmacological profile, it was of interest to critically appraise clinical trials of thromboprophylaxis and treatment with these new agents. In orthopedic trials, it was noted that LMWH provided safe and effective thromboprophylaxis for patients undergoing major orthopedic surgery of the lower limb. In those having hip arthroplasty, LMWH was as effective as low-intensity warfarin therapy, but its use was associated with more wound hematomas. In those having total knee arthroplasty, LMWH was more effective than warfarin and did not increase bleeding. However, the prevalence of DVTs complicating this procedure as well as acute hip fracture remains unacceptably high, and additional studies of LMWH in combination with other prophylactic methods, such as external pneumatic compression, are needed. Only one adequately designed trial found less bleeding resulted from LMWH prophylaxis administered at an equivalent antithrombotic dose to UFH. In general medical patients, LMWH appeared to be as effective as UFH and had the advantages of less frequent injections and fewer injection site hematomas. In general surgical patients, there was a lower risk of thromboembolism but a trend toward an increase in bleeding events. Subjects with strokes and spinal cord injuries benefited from fewer thrombotic events, and the latter had fewer bleeding complications. Other potential indications for LMWH, such as cardiopulmonary bypass, hemodialysis, and preservation of graft patency, are presently under study. Perhaps the most impressive benefits of LMWH will be realized when it is used for the treatment of venous thromboembolism. The meta-analysis presented in this review showed a trend toward greater efficacy with LMWH and fewer major bleeding events in comparison with adjusted-dose intravenous UFH. Also, during the months following the thrombotic event, there was significantly less mortality in patients receiving LMWH. A further advantage was the subcutaneous route of administration and lack of requirement for laboratory monitoring. Additional treatment trials are presently in progress and may establish LMWH as the treatment of choice for patients with thromboembolic disorders.

Animals↗
PubMed1993

Calcitonin gene-related peptide and substance P immunoreactivity in the monkey trigeminal ganglion, an electron microscopic study.

Calcitonin gene-related peptide (CGRP) and substance P (SP) immunoreactivity was examined in neurons of the monkey trigeminal ganglion. Moreover, CGRP- and SP-positive varicose nerve fibers were found, occasionally forming pericellular arborizations around trigeminal somata, which, at light microscopic level, suggested the existence of synaptic contacts. Electron microscopic investigation however, revealed that although these varicose fibers ran in close range of somata and were containing accumulations of CGRP- and SP-positive vesicles, classical synaptic contacts were not present.

Animals↗
PubMed1993

Complex formation determines the activity of ribozymes directed against potato virus YN genomic RNA sequences.

A ribozyme was synthesized against a conserved region in the RNA-dependent RNA-polymerase encoding cistron of the important plant pathogen potato virus Y (PVY). This ribozyme was shown to cleave PVY-specific RNA-transcripts efficiently in vitro, with up to 95% of the substrate RNA being cleaved within 2 h incubation at 37 degrees C. A second ribozyme, designed with much shorter viral complementary arms in an attempt to optimize the efficiency of the cleavage reaction, surprisingly failed to cleave the substrates previously cleaved by the longer ribozyme. A much shorter PVY specific RNA-transcript of only 37 nucleotides (nt), however, was cleaved by this short ribozyme proving its ribozymic activity and indicating that the cleavage activity of the ribozyme is, in part, determined by the substrate involved. Analysis of cleavage reactions on non-denaturing polyacrylamide (PAA) gels indicated that incorrect basepairing, interfering with correct formation of the hammerhead structure, was likely to be responsible for the absence of detectable cleavage of the larger substrates by the short ribozyme.

Base Sequence↗
PubMed1993

Innervation of the superior tarsal (Müller's) muscle in the cynomolgus monkey: a retrograde tracing study.

PURPOSE: The retrograde transport of wheat germ agglutinin-horseradish peroxidase (WGA/HRP) was used to study the localization of the neurons that innervate the superior tarsal muscle in the cynomolgus monkey. METHODS: A 5-10% WGA-HRP solution was applied to the medial part of the superior tarsal muscle. Seventy-two hours later, the animals were killed and perfused with fixative. RESULTS: The WGA-HRP-labeled neurons were localized in the ipsilateral trigeminal ganglion, the ipsilateral pterygopalatine ganglion, and the ipsilateral superior cervical ganglion. The labeled somata of the sensory neurons were all found in the ophthalmic ganglionic part and the ophthalmic nerve part of the ipsilateral trigeminal ganglion. Most of the labeled somata were distributed somatotopically in the dorsal region of the ophthalmic part of the ganglion. The labeled somata of the sympathetic neurons were all located in the ipsilateral superior cervical ganglion. Most of these labeled somata, which were distributed somatotopically, were found in the cranial part of the ganglion. The labeled somata of the parasympathetic neurons were all located in the ipsilateral pterygopalatine ganglion, particularly in the central ovoid part of the ganglion. No labeled neurons were detected in the ipsilateral parasympathetic ciliary ganglion, the ipsilateral nodose ganglion, or the first three ipsilateral sensory spinal ganglia; labeled somata could not be detected in any of the contralateral ganglia examined. CONCLUSIONS: A complete documentation of all projections of the superior tarsal muscle in the monkey has been presented, and convincing data has been given about the parasympathetic innervation of Müller's muscle.

Animals↗
PubMed1992

Heparin binding to plasma proteins, an important mechanism for heparin resistance.

Heparin dosage requirements vary widely among patients with venous thromboembolism. In this study, we measured the proportion of anticoagulantly-active heparin which was reversibly bound and neutralized by plasma proteins (defined as reversible heparin neutralization) in the pre-treatment plasma (in vitro) and in the 6 h post-treatment plasma (ex vivo) of patients with venous thromboembolism treated with a fixed dose of heparin. Reversible heparin neutralization was assessed by comparing the heparin levels measured as anti-factor Xa activity before and after the addition of low affinity heparin which is essentially devoid of anti-factor Xa activity, in order to displace heparin bound to plasma proteins. The results indicate that reversible heparin neutralization due to binding to plasma proteins is a major determinant of the anticoagulant response to a fixed dose of standard heparin 6 h post-treatment and of the eventual heparin dose required to achieve a therapeutic anticoagulant effect on days 3-5 of heparin treatment.

Adult↗
PubMed1992

Characterization of RNA-mediated resistance to tomato spotted wilt virus in transgenic tobacco plants.

Recently high levels of protection against tomato spotted wilt virus (TSWV), a negative-strand RNA virus infecting plants, have been obtained by transforming tobacco with viral nucleoprotein (N) gene sequences. Here we demonstrate that this protection is primarily due to the presence of N gene transcripts in the cells of transgenic plants, and hence appears to be RNA-mediated. Further, transgenic tobacco plants are only protected to isolates and strains of TSWV and not to other tospoviruses that share considerable nucleotide sequence homology in their N genes to TSWV. In addition to being protected after mechanical inoculation, the transgenic tobacco plants are also resistant to inoculation using viruliferous thrips, i.e. Frankliniella occidentalis (Perg.), one of the most important natural vector species.

Cell Line, Transformed↗
PubMed1992

The pattern of trunk lateral line afferents and efferents in the rainbow trout (Salmo gairdneri).

The primary projections of the mechanosensory posterior lateral line nerve of the rainbow trout Salmo gairdneri, a teleost without lateral line specializations, were studied by applying horseradish peroxidase (HRP). The afferents project nearly exclusively to the nucleus medialis and a small nucleus caudalis in the hindbrain, and to the eminentia granularis. In addition, there is a sparse projection to the cerebellum, but a projection to the magnocellular nucleus is lacking. The afferent projection to the lateral part of the eminentia granularis is more dense than the projection to the medial nucleus, as shown by image processing of the HRP labeling. The efferent fibers originate from a bilateral pair of large octavolateral nuclei in the hindbrain. Characteristic for these nuclei are their large, fusiform and bipolar neurons. Another specific feature is the oblique orientation of the somata, with the main dendritic shaft coursing ventrolaterally and the axonal shaft coursing dorsomedially. The axons of the efferent neurons bifurcate. The shape, orientation and size of the efferent somata are the same in the entire efferent nucleus. In contrast to other teleosts, the occurrence of efferent somata found contralaterally (21%) is substantial. The part of the octavolateral efferent nucleus innervating the neuromasts of the trunk is estimated to contain at most 150 cell bodies unilaterally.

Afferent Pathways↗
PubMed1991

Characterization of the pea ENOD12B gene and expression analyses of the two ENOD12 genes in nodule, stem and flower tissue.

The ENOD12 gene family in pea consists of two different members. The cDNA clone, pPsENOD12, represents the PsENOD12A gene. The second ENOD12 gene, PsENOD12B, was selected from a genomic library using pPsENOD12 as a probe and this gene was sequenced and characterized. The coding regions of the two genes are strikingly similar. Both encode proteins having a signal peptide sequence and a region with pentapeptide units rich in prolines. ENOD12A has a series of rather conserved repeating pentapeptide units, whereas in ENOD12B the number of pentapeptide units is less and these are less conserved. From the amino acid sequence it is obvious that the PsENOD12 genes encode proline-rich proteins which are closely related to proteins that have been identified as components of soybean cell walls (SbPRPs). Previously, Northern blot analyses had shown that ENOD12 genes are expressed in a tissue-specific manner. A high expression level is found in Rhizobium-infected roots and in nodules, whereas expression in flower and stem is lower. This raised the question of which gene is expressed where and when. The availability of the sequences of both ENOD12 genes allowed us to analyse the expression of the two genes separately. Specific oligonucleotides were used to copy the ENOD12 mRNAs and to amplify the cDNAs in a polymerase chain reaction. It was demonstrated that in all the tissues containing ENOD12 mRNA, both genes PsENOD12A and PsENOD12B are transcribed and that the relative amounts of PsENOD12A and PsENOD12B mRNA within each tissue are more or less equal. Moreover, the expression pattern during infection and nodule development is the same for the two genes.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMedDate not supplied

Broad resistance to tospoviruses in transgenic tobacco plants expressing three tospoviral nucleoprotein gene sequences.

Transgenic tobacco plants have been obtained expressing nucleoprotein (N) gene sequences of three different tospoviruses known to affect vegetable crops: tomato spotted wilt virus (TSWV), tomato chlorotic spot virus (TCSV), and groundnut ringspot virus (GRSV). The chimeric plant transformation vector used comprised the three viral N gene sequences, each with a copy of the CaMV 35S promoter and the nos terminator. Despite the high levels of homology between the different N gene sequences (74-82%) and the presence of repeated promoter and terminator sequences in this construct, unrearranged copies of this triple N gene construct were stably maintained in both Escherichia coli and Agrobacterium tumefaciens plasmids used during the cloning process, as well as in several generations of transgenic tobacco plants. A transgenic tobacco line was obtained that exhibited high levels of resistance to all three tospoviruses, showing the possibility of producing transgenic plants with a broad resistance to tospoviruses by introducing tandemly cloned viral N gene sequences. DNA analysis of this transgenic plant line shows that the multivirus resistance trait is confined to a single genetic locus, which is very convenient for further breeding purposes.

Agrobacterium tumefaciens↗
PubMedDate not supplied

Incidence and risk factors for acquisition of sexually transmitted diseases in heterosexuals with multiple partners.

BACKGROUND AND OBJECTIVES: The incidence of four STDs that are mainly transmitted during vaginal intercourse, and risk factors for acquisition during follow-up were studied in a cohort of heterosexuals with multiple partners in Amsterdam, the Netherlands. These heterosexuals with > or = 5 different sexual partners in the preceding 6 months were recruited from an STD clinic and participated voluntarily in a longitudinal HIV study between 1987 and 1991. STUDY DESIGN: Using survival techniques, the authors analyzed data on general characteristics, sexual behavior, reported and diagnosed STDs of 155 men and 234 women participating at least twice in the HIV study and returning regularly. RESULTS: The majority of women were prostitutes and the majority of men were clients of prostitutes. For men and women, the 2-year cumulative incidence were 2.7% (95% confidence interval [95% CI] 0.9-8.3) and 0.8% (95% CI 0.1-5.8), respectively, for syphilis, 8.5% (95% CI 3.9-18.0) and 5.3% (95% CI 2.6-10.8) for gonorrhea, 20.2% (95% CI 12.5-31.9) and 31.9% (95% CI 23.7-42.2) for Chlamydia trachomatis infection, and 24.5% (95% CI 17.3-34.2) for trichomoniasis (examination in women only). Among men, STD(s) diagnosed at entry was found to be an independent predictor of infection with any of these STDs during follow-up (relative hazard (RH) = 2.58, 95% CI 1.18-5.64). Among women, risk factors were age < or = 25 years (RH = 1.82, 95% CI 1.13-2.19) and current report of commercial unprotected vaginal contacts (RH = 2.19, 95% CI 1.11-4.13). Among women, trichomoniasis during follow-up was predicted by current report of commercial contacts (RH = 2.59, 95% CI 1.16-5.79). C. trachomatis infection in women was associated with native country outside the Netherlands (RH = 2.47, 95% CI 1.38-4.43), reported history of STDs in the 4 months before the study (RH = 2.92, 95% CI 1.39-6.14) and age < or = 25 years (RH = 1.90, 95% CI 1.06-3.40). CONCLUSIONS: This study shows that STDs were common among this group of heterosexuals, despite regularly participating in the HIV study in which consistent condom use was promoted. Prevention efforts should be intensified for men and women having commercial sexual contacts, young women, and individuals with a history of STDs.

Adult↗