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Biomedical subjects

T C Quinn

Publications and source records attributed to T C Quinn.

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

Chlamydia, gonorrhea, and HIV-1 prevalence among five populations of women in the Czech and Slovak Republics.

BACKGROUND: Five populations at risk for sexually transmitted diseases (STDs) in the Czech and Slovak Republics were sampled. GOAL: To estimate prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, and HIV-1 infections. STUDY DESIGN: Urine specimens were collected serially from women at a Prague prenatal clinic (n = 134), a Prague dermatovenerealogy clinic (n = 91), sex workers from northern and central Bohemia (n = 35), students from a northern Bohemian school (n = 217), and Gypsies from Jarovnice, Slovakia (n = 128). These specimens were tested for chlamydia and gonorrhea using a ligase chain reaction pooling algorithm, and for HIV using an enzyme immunoassay confirmed by Western blot. RESULTS: The prevalence of chlamydia was 2.2% (95% CI, 0.4-6.4) in the prenatal clinic, 5.5% (95% CI, 1.8-12.4) in the STD clinic, 22.9% (95% CI, 10.4-40.1) among street sex workers, 8.2% (95% CI, 3.6-15.6) among sexually active female high school students, and 3.9% (95% CI, 1.3-8.9) among Gypsy women. Gonorrhea was found in only two populations: 2.2% (95% CI, 0.3-7.7) in the STD clinic, and 2.9% (95% CI, 0.1-14.9) among sex workers. No HIV-1 infection was detected. CONCLUSIONS: Urine screening was an efficient and accurate method for identifying groups at risk for STDs in the Czech Republic and Slovakia because sample collection was fast and noninvasive, and potential participation bias was reduced by high acceptability.

Adolescent↗
PubMed2001

Modification of syphilitic genital ulcer manifestations by coexistent HIV infection.

BACKGROUND: Conflicting data exist regarding whether HIV infection leads to changes in the clinical manifestations and severity of genital ulcer disease (GUD). GOAL: To determine the impact of HIV on the etiology and clinical severity of GUD. STUDY DESIGN: From July 1990 to July 1992, consecutive patients presenting to the two Baltimore City Health Department (BCHD) Sexually Transmitted Diseases clinics were approached as candidates for enrollment in a prospective study to determine factors associated with the transmission and acquisition of sexually transmitted diseases (STDs). RESULTS: Of the 1368 patients who presented to the BCHD, 214 (16%) had genital ulcerations: 160 (21%) of 757 men and 54 (9%) of 611 women. Among the patients with GUD who had undergone HIV testing, 28 (14%) of 204 were infected with HIV: 25 (17%) of 151 men and 3 (6%) of 53 women. Although both groups-those infected with HIV and those not infected with HIV--presented with GUD of similar duration (10 versus 11 days; P = 0.17), multiple lesions were found more frequently in men with HIV infection than in uninfected men: 87% versus 62% (P = 0.02). Although not statistically significant, GUD in men with HIV infection more often were deep (64% versus 44%, respectively) rather than superficial (36% versus 57%, respectively; P = 0.08), and larger (505 mm(2) versus 109 mm 2; P = 0.06). Primary syphilis caused more GUD among men with HIV infection than among uninfected men: 9 (36%) of 25 versus 24 (19%) of 126, respectively (P < 0.01). Secondary syphilis was diagnosed with concomitant GUD more frequently among men with HIV infection than among uninfected men: 3 (13%) of 25 versus 3 (2%) of 123, respectively (P < 0.01). CONCLUSIONS: In this study, patients who presented with GUD were more likely to be infected with HIV. A higher proportion of men with HIV infection had multiple lesions, and the lesions were more likely to be caused by syphilis.

Adolescent↗
PubMed2001

Adolescent chlamydia testing practices and diagnosed infections in a large managed care organization.

GOAL: To determine chlamydia screening practices and the resulting positive test results for adolescents enrolled in a large nonprofit managed care organization. STUDY DESIGN: The electronic medical records of all 12- to 19-year-olds enrolled in a large nonprofit managed care organization serving a demographically diverse patient population from January 1998 through December 1999 were reviewed retrospectively. RESULTS: Among the 43,205 female and 44,133 male managed care organization members, ages 12 to 19 years in 1998-1999, 7575 adolescents (8.7%) (6914 females [16%] and 661 males [1.5%]) were tested for chlamydia. Among the members tested, chlamydia was diagnosed in 1109 adolescents (14.6%) (983 females [14.2] and 126 males [19.1%]); 761 (68.6%) adolescents were retested for chlamydia; and 182 (16.4%) had repeat positive test results. The median time to diagnosis of a repeat infection was 6 months. CONCLUSIONS: Chlamydia imposes a large disease burden in the private, organized healthcare sector. Managed care organizations can use operational data to enhance chlamydia prevention services by defining testing practices and local disease prevalence.

Adolescent↗
PubMed2001

Enhancing the specificity of the COBAS AMPLICOR CT/NG test for Neisseria gonorrhoeae by retesting specimens with equivocal results.

The COBAS AMPLICOR CT/NG test for Neisseria gonorrhoeae cross-reacts with certain strains of nonpathogenic Neisseria species. In some strains, the target sequence is identical to that of N. gonorrhoeae, whereas other strains have a small number of mismatches within the regions recognized by the primers or probe used in the COBAS AMPLICOR NG test. These cross-reactive strains are occasionally present in urogenital specimens, causing false-positive results in the COBAS AMPLICOR NG test. Analysis of the data generated in a large multicenter clinical trial showed that 2.9% of the specimens gave signals between A(660)s of 0.2 and 3.5 but that one-half of these equivocal specimens did not contain N. gonorrhoeae. Most of these equivocal specimens were correctly classified as true positive or true negative by retesting in duplicate and defining a PCR-positive result as two of three results with an A(660) of > or =2.0. If specimens had been classified as positive or negative based on a single test result using a cutoff of an A(660) of 0.2, specificity would have ranged from 96.2 to 98.9% depending on specimen type, sex, and presence of symptoms. By employing the equivocal zone-retesting algorithm, specificity increased to 98.6 to 99.9% with little effect (0.1 to 4.9% decrease) on sensitivity in most specimen types, enabling the test to achieve a positive predictive value of at least 90% in populations with a prevalence of 4% or higher. In lower-prevalence populations, the test could be used to screen for presumptive infections that would have to be confirmed by an independent test.

Adult↗
PubMed2001

Predictors of repeat Chlamydia trachomatis infections diagnosed by DNA amplification testing among inner city females.

OBJECTIVE: To describe the epidemiology of prevalent and incident chlamydia infection in order to assess the appropriate interval for chlamydia screening; and to identify risk factors predictive of infection and repeat infections. DESIGN: Prospective longitudinal study of a consecutive sample of 3860 sexually active females aged 12-60 years tested for C. trachomatis by polymerase chain reaction in Baltimore City clinics during 11,904 patient visits over a 33 month period. RESULTS: Chlamydia prevalence, incidence, and frequency to diagnosis of infection varied by age. Among 2073 females < 25 years, chlamydia infection was found in 31.2%. The median times to first and repeat incident infections were 7.0 months and 7.6 months, respectively. Among 1787 females > or = 25 years, chlamydia infection was found in 9.6%. Median times to first and repeat incident infections were 13.8 months and 11.0 months, respectively. Age < 25 years yielded the highest risk of infection. CONCLUSIONS: Since a high burden of chlamydia was found among mostly asymptomatic females < 25 years in a spectrum of clinical settings, we recommend chlamydia screening for all sexually active females < 25 years at least twice yearly.

Adolescent↗
PubMed2001

Presence of Chlamydia pneumoniae in human symptomatic and asymptomatic carotid atherosclerotic plaque.

BACKGROUND: Chlamydia pneumoniae has been identified in atherosclerotic plaques of patients with cerebrovascular and cardiovascular disease. However, the direct causative effect of C pneumoniae infection in the activation of atherosclerotic plaque to a prothrombotic state remains to be established. The aim of the present study is to examine the correlation between intraplaque presence of chlamydiae and symptomatic carotid disease in humans. METHODS: Plaques from 37 symptomatic and 57 asymptomatic consenting patients undergoing carotid endarterectomy were snap-frozen, and the tissue was prepared for polymerase chain reaction analysis for Chlamydia pneumoniae per Institutional Review Board-approved protocol. Blood was drawn from each patient at the time of surgery for serological analysis. RESULTS: The overall rate of plaques positive for C pneumoniae was 14.82%, with 5 of 37 (13.5%) plaques from symptomatic patients and 9 of 57 (15.8%) from asymptomatic patients, which revealed a definitive presence of the organism. No association existed between C pneumoniae presence and symptomatic disease (P:=1.0). Also, no association existed between presence of C pneumoniae and severity of stenosis. Finally, seropositivity for anti-chlamydial IgG, IgA, and IgM anti-chlamydial antibodies did not correlate with identification of C pneumoniae in the plaques. However, high-serum anti-chlamydial IgA levels (>/=1:128) were associated with occurrence of symptomatic disease (P=0.03; odds ratio, 2.86; 95% CI, 1.12 to 7.28). CONCLUSIONS: Presence of C pneumoniae as a single factor does not appear to be sufficient to explain the occurrence of cerebrovascular symptoms. Low sensitivity of seropositivity for IgG, IgA, or IgM associated with PCR-identified C pneumoniae presence in the plaque makes it unlikely to be valuable as the single determining factor for actively infected plaque. Association of high-level anti-chlamydial IgA with symptomatic disease suggests that chronic or acute chlamydial infection anywhere in the body could play a role in atherosclerotic plaque activation and be used as a marker to target populations in future stroke prevention trials.

Aged↗
PubMed2000

Atherosclerosis in apoE knockout mice infected with multiple pathogens.

Cytomegalovirus (CMV) and Chlamydia pneumoniae (CP) possibly contribute to atherosclerosis. Murine CMV (MCMV) and CP increase lesion size in apoE knockout mice. In this study, apoE knockout mice were infected with MCMV and CP to determine whether infection with multiple pathogens increases lesion size to a greater extent than either pathogen alone and whether infection with MCMV changes serum cytokine levels in a manner that could increase lesion development. One group of mice received MCMV at 2 weeks of age, followed by 2 doses of CP at 6 and 8 weeks of age. Additional groups received only MCMV or CP. Animals were killed at 16 weeks of age to determine lesion area. Infection with MCMV alone, CP alone, and both MCMV and CP increased lesion size 84% (P<.001), 70% (P<.0001), and 45% (P<.01), respectively. The MCMV-induced increase in circulating levels of interferon-gamma may have contributed to this increase.

Animals↗
PubMed2000

Effect of azithromycin on murine arteriosclerosis exacerbated by Chlamydia pneumoniae.

Chlamydia pneumoniae infection can exacerbate atherosclerosis in animals. To test the hypothesis that antibiotic therapy inhibits the atherogenic effects of C. pneumoniae infection, 10-week-old apolipoprotein E (ApoE) null mice were infected with C. pneumoniae or placebo, were treated for 2 weeks after infection with azithromycin or placebo, and were killed at 20 weeks of age. Infection did not affect the size of the aortic lesion, and antibiotic treatment had no effect. Another group of mice, 12-week-old ApoE mice, were infected with C. pneumoniae or placebo, were treated for 2 weeks after infection with azithromycin or placebo, and were killed at 26 weeks of age. C. pneumoniae infection increased the size of the lesion in infected mice, but azithromycin did not reduce the size of the aortic lesion in infected mice. Therefore, immediate therapy of acute infection may be necessary to prevent the proatherogenic effects of C. pneumoniae infection.

Animals↗
PubMed2000

Feasibility of pooling sera for HIV-1 viral RNA to diagnose acute primary HIV-1 infection and estimate HIV incidence.

OBJECTIVE: To develop a pooling method for detection of viral RNA for diagnosis of acute HIV infection and estimation of HIV-1 incidence. METHODS: Sera from 700 consecutive seronegative patients attending sexually transmitted disease clinics in Pune, India, were screened individually for p24 antigen, and pooled into seven pools of 100 for detection of HIV-1 RNA by reverse transcriptase-polymerase chain reaction. HIV-1 incidence was calculated by the traditional cohort method, the p24 antigen method, and a multistage pooling method in which RNA-positive pools were re-analyzed in smaller pools. RESULTS: Sera from 700 individuals were grouped into seven pools of 100, of which four were positive. These four positive pools were subdivided into eight pools of 50, of which seven were positive. The seven positive pools were subdivided into 35 pools of 10, of which 10 were positive. Based on the 10 RNA-positive pools, the point estimate of HIV-1 incidence was 19.9% per year [95% confidence interval (CI), 7.3-31.8%]. Of the 700 samples analyzed for p24 antigen, eight were positive, resulting in a point estimate of incidence of 18.5%/year (8.0-36.5%). In contrast, the incidence rate based on the traditional cohort method of follow-up was lower at 9.4%/year (4.8-16.4%) due to a low follow-up rate. Testing of individual samples from the 10 RNA-positive pools identified 10 individuals with acute primary HIV-1. CONCLUSION: The multistage pooling method for detection of HIV-1 RNA was more sensitive than the p24 antigen method, and was five-fold less expensive than the p24 antigen assays. Pooling samples for RNA detection was effective in estimating current incidence rates with cost savings that would be practical for use in developing countries.

Follow-Up Studies↗
PubMed2000

Biphasic decay of latently infected CD4+ T cells in acute human immunodeficiency virus type 1 infection.

Latent infection of resting CD4(+) T cells represents a major barrier to eradication of human immunodeficiency virus type 1 (HIV-1). The establishment and rate of decay of latent HIV-1 in resting CD(+) T cells from 9 acute seroconverters, 7 of whom began to receive highly active antiretroviral therapy (HAART) shortly after presentation, were studied. Before the initiation of therapy, these patients had very high frequencies of latently infected CD4(+) T cells, with a median frequency of 205 infectious units per million resting CD4(+) T cells. These values are > or =1 log higher than those seen in chronically infected patients who are not undergoing HAART. The number of latently infected cells declined dramatically after initiation of HAART but then tended to level off at a low but stable level. The biphasic decay of latent HIV in resting CD4(+) T cells in acute seroconverters supports current models of pre- and postintegration latency.

Acute Disease↗
PubMed2000

Male circumcision and HIV acquisition and transmission: cohort studies in Rakai, Uganda. Rakai Project Team.

BACKGROUND: Male circumcision is associated with reduced HIV acquisition. METHODS: HIV acquisition was determined in a cohort of 5507 HIV-negative Ugandan men, and in 187 HIV-negative men in discordant relationships. Transmission was determined in 223 HIV-positive men with HIV-negative partners. HIV incidence per 100 person years (py) and adjusted rate ratios (RR) and 95% confidence intervals (CI) were estimated by Poisson regression. HIV-1 serum viral load was determined for the seropositive partners in HIV-discordant couples. RESULTS: The prevalence of circumcision was 16.5% for all men; 99.1% in Muslims and 3.7% in non-Muslims. Circumcision was significantly associated with reduced HIV acquisition in the cohort as a whole (RR 0.53, CI 0.33-0.87), but not among non-Muslim men. Prepubertal circumcision significantly reduced HIV acquisition (RR 0.49, CI 0.26-0.82), but postpubertal circumcision did not. In discordant couples with HIV-negative men, no serconversions occurred in 50 circumcised men, whereas HIV acquisition was 16.7 per 100 py in uncircumcised men (P = 0.004). In couples with HIV-positive men, HIV transmission was significantly reduced in circumcised men with HIV viral loads less than 50000 copies/ml (P = 0.02). INTERPRETATION: Prepubertal circumcision may reduce male HIV acquisition in a general population, but the protective effects are confounded by cultural and behavioral factors in Muslims. In discordant couples, circumcision reduces HIV acquisition and transmission. The assessment of circumcision for HIV prevention is complex and requires randomized trials.

Adolescent↗