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T C Quinn

Publications and source records attributed to T C Quinn.

At least 73 records · Page 4Linked to original sources
PubMed1999

In vitro infection and pathogenesis of Chlamydia pneumoniae in endovascular cells.

The strength of the epidemiologic and clinical associations of Chlamydia pneumoniae with atherosclerosis can be increased by the demonstration that C pneumoniae can initiate and sustain growth in human vascular cells as well as in animal models. To investigate the biological basis for the dissemination and proliferation of this organism in vascular cells, the in vitro growth of C pneumoniae was studied in 2 macrophage cell lines, peripheral blood monocyte (PBMC)-derived macrophages, human bronchoalveolar lavage (BAL) macrophages, several endothelial cell lines, and aortic artery smooth muscle cells. Five of 5 strains of C pneumoniae were capable of 3 passages in human U-937 macrophages and in murine RAW 246.7 macrophages. Titers were suppressed in both macrophage types with each passage as compared with growth in HEp-2 cells. Both human BAL macrophages and PBMC-derived macrophages were able to inhibit C pneumonia eafter 96 hours' growth. Eleven C pneumoniae strains were capable of replicating in normal human aortic artery-derived endothelial cells, umbilical vein-derived endothelial cells, and pulmonary artery endothelial cells. Infection in human aortic artery smooth muscle cells was also established for 13 strains of C pneumoniae. C pneumoniae was also capable of growing in endothelial cells derived from human cadaver coronary artery endothelial cells (CAEC). U-937 human macrophages that were infected with C pneumoniae were capable of transmitting the infection to CAEC when they were brought into contact with the endothelial cells by centrifugation, rocking overnight, and direct layering overnight, with and without using artificial laboratory tissue culture enhancements, such as centrifugation of the inoculum and cycloheximide in the growth media. The in vitro ability of C pneumoniae to maintain infections in macrophages, endothelial cells, and aortic smooth muscle cells may provide support for the hypothesis that C pneumoniae can infect such cells, which when followed by an immune response may contribute to atheroma formation in vivo. Stimulation of cytokine responses by infection with C pneumoniae has indicated that this organism is capable of interacting with the immune system. In vitro infection by C pneumoniae of U-937 macrophages stimulated the production of IL-1beta, IFN-gamma, and TNF-alpha in tissue culture. Human CAEC that are infected with C pneumoniae produce more IL-8 compared with those inoculated with killed C pneumoniae or negative control cells, indicating a chemokine response to infection that may play a role in recruitment of inflammatory cells to sites of infection in vascular cells. When IFN-gamma was used to up regulate HEp-2 and U-937 cells before infection by C pneumoniae, inhibition of a lytic growth cycle occurred in a dose related response. However, removal of the IFN-gamma after 24 to 48 hours' exposure allowed subsequent productive growth in the cells, perhaps indicating the prior induction of a persistent infection. More studies are needed to study the complex relationship between lytic infection and persistence, the ability of C pneumoniae to affect the immune response of vascular cells, and the potential for C pneumoniae to influence the initiation of or progression of atheromatous lesions.

Cell Division↗
PubMed1999

Emergency department-based HIV screening and counseling: experience with rapid and standard serologic testing.

STUDY OBJECTIVE: We sought to (1) determine whether some emergency departments could play an important role in the national strategy of early HIV detection through the implementation of a voluntary HIV screening program and (2) describe the experience with standard and rapid HIV testing. METHODS: Consenting adults were enrolled during 3 distinct phases between 1993 and 1995 for the assessment of routine testing only, routine versus rapid testing, and rapid testing only. Patients administered the rapid test were given information at the time of the visit. We assessed the cost of the program. RESULTS: Of 3,048 patients approached, 1,448 (48%) consented, 981 to standard and 467 to rapid testing. Of these, 6.4% and 3.2%, respectively, were newly identified as being HIV seropositive. More than twice as many new infections were diagnosed among those discharged from the ED as among those admitted (55 versus 21). Even among those previously tested, 5% proved seropositive. The mean+/-SD time to obtain results for the rapid assay performed in the hospital's main laboratory was 107+/-52 minutes, with 55% leaving the ED before receiving the results. Rapid assays performed in the ED satellite laboratory required 48+/-37 minutes, and only 20% left before getting the results. Follow-up among HIV-seropositive patients was 64% for the standard protocol and 73% for the rapid protocol (P >. 20). The prearranged HIV clinic intake appointment was kept by 62%. Rapid test sensitivity and specificity were 100% and 98.9%, respectively, with 5 initial false-positives and no false-negatives. Cost per patient enrolled and counseled was $38. Cost per infection detected was $601 for the routine test and $1,124 with the rapid test; these prices are competitive with those incurred at other sites. CONCLUSION: Emergency department-based HIV testing was well accepted and detected a significant number of new HIV infections earlier than might have otherwise been, particularly among patients sent home. The rapid test is best performed on-site and is very sensitive. Confirmation of initial results is required because of the occurrence of occasional false-positive results. With relatively high HIV detection and return rates, it is evident that some EDs could play a major role in the national strategy of early HIV detection.

Adolescent↗
PubMed1999

Latent infection of CD4+ T cells provides a mechanism for lifelong persistence of HIV-1, even in patients on effective combination therapy.

Combination therapy for HIV-1 infection can reduce plasma virus to undetectable levels, indicating that prolonged treatment might eradicate the infection. However, HIV-1 can persist in a latent form in resting CD4+ T cells. We measured the decay rate of this latent reservoir in 34 treated adults whose plasma virus levels were undetectable. The mean half-life of the latent reservoir was very long (43.9 months). If the latent reservoir consists of only 1 x 10(5) cells, eradication could take as long as 60 years. Thus, latent infection of resting CD4+ T cells provides a mechanism for lifelong persistence of HIV-1, even in patients on effective anti-retroviral therapy.

Adult↗
PubMed1999

Human immunodeficiency virus load in breast milk, mastitis, and mother-to-child transmission of human immunodeficiency virus type 1.

Human immunodeficiency virus (HIV) type 1 load in breast milk and mastitis were examined as risk factors for vertical transmission of HIV-1. Six weeks after delivery, HIV-1 load and sodium (an indicator of mastitis) were measured in breast milk from 334 HIV-1-infected women in Malawi. Median breast milk HIV-1 load was 700 copies/mL among women with HIV-1-infected infants versus undetectable (<200 copies/mL) among those with uninfected infants, respectively (P<. 0001). Elevated breast milk sodium levels consistent with mastitis occurred in 16.4% of HIV-1-infected women and were associated with increased vertical transmission of HIV-1 (P<.0001). Median breast milk HIV-1 load was 920 copies/mL among women with versus undetectable among those without elevated breast milk sodium levels, respectively (P<.0001). Mastitis and breast milk HIV-1 load may increase the risk of vertical transmission of HIV-1 through breast-feeding.

Adult↗
PubMed1999

Sex differences in longitudinal human immunodeficiency virus type 1 RNA levels among seroconverters.

Cross-sectional studies have demonstrated lower plasma human immunodeficiency virus type 1 (HIV-1) RNA virus levels (VLs) in women than in men, but it is unknown whether this sex difference is present at the time of seroconversion and throughout the course of infection. A nested case-control study was performed among HIV-1 seroconverters within a cohort of injection drug users. Plasma VL was determined longitudinally among both rapid progressors to AIDS (24 patients) and nonprogressors (47 controls). The initial median VL among female patients (n=10) was 14,918 copies/mL, compared with 148,354 copies/mL among male patients (n=14; P=.001); median plasma VL also tended to be lower among female (n=10) than among male controls (n=37; 11,917 vs. 61,311 copies/mL; P=.08). VL increased more rapidly over time in women than in men and subsequently converged in patients and controls, respectively. Understanding the mechanisms responsible for the sex difference in VL may provide insight into HIV-1 pathogenesis.

Acquired Immunodeficiency Syndrome↗
PubMed1999

The etiology of genital ulcer disease by multiplex polymerase chain reaction and relationship to HIV infection among patients attending sexually transmitted disease clinics in Pune, India.

OBJECTIVES: To determine the etiology of genital ulcer disease (GUD) among patients attending sexually transmitted disease (STD) clinics in Pune, India, and to examine the relationship to HIV infection and compare the clinical diagnosis of GUD with the results of a multiplex polymerase chain reaction (M-PCR) assay for Treponema pallidum, herpes simplex virus (HSV), and Hemophilus ducreyi infection. METHODS: Between June 20, 1994, and September 26, 1994, 302 patients with a genital ulcer were evaluated. Clinical etiology of GUD was based on physical appearance and microbiologic evaluations which included darkfield microscopy and serology for syphilis. Swabs of each genital ulcer were tested for HSV antigen by enzyme immunoassay (Herpchek; Dupont, Wilmington, DE) and processed in a multiplex PCR assay (M-PCR; Roche, Branchburg, NJ) for simultaneous detection of HSV, Treponema pallidum, and Hemophilus ducreyi. RESULTS: Two hundred seventy-seven men and 25 women with a median age of 25 were evaluated. The seroprevalence of HIV was 22.2%. The etiology of GUD as determined by M-PCR was HSV (26%), H. ducreyi (23%), T. pallidum (10%), and multiple infections (7%); no etiology was identified in 34%. HIV seroprevalence was higher among those patients positive for HSV compared with other etiologies (OR = 2.1, CI: 1.2-3.7; p = 0.01). When compared with M-PCR, the Herpchek test was 68.5% sensitive and 99.5% specific. Darkfield detection for T. pallidum was 39% sensitive and 82% specific, in contrast to rapid plasma reagin and fluorescent treponemal antibody absorption test, which was 66% sensitive and 90% specific. Clinical diagnosis alone or in combination with basic laboratory tests showed poor agreement with M-PCR.

Adolescent↗
PubMed1999

Control of Chlamydia trachomatis infections in female army recruits: cost-effective screening and treatment in training cohorts to prevent pelvic inflammatory disease.

CONTEXT: Chlamydia trachomatis genitourinary infections in females can lead to serious and costly sequelae. Programs such as basic (initial entry) military training with controlled points of entry offer an opportunity to screen large cohorts of women at risk for infection. OBJECTIVE: To assess the cost-effectiveness of three interventions for C. trachomatis infections in women beginning Army training: 1) screening using urine ligase chain reaction (LCR) by age, 2) unrestricted testing using urine LCR, and 3) universal antibiotic treatment with azithromycin. DESIGN: Cost-effectiveness analysis from a military perspective. SETTING AND PATIENTS: A hypothetical cohort of 10,000 women who intended to complete at least 2 years of military service was studied. Analysis was based on data from 13,204 female trainees screened for chlamydial infection at Fort Jackson, SC. OUTCOMES: Program and training costs, cost of illness averted, and pelvic inflammatory disease (PID) prevented were determined for a 1-year follow-up period. Using sensitivity analysis, outcomes over 2 years were studied. RESULTS: At a 9.2% prevalence, no screening resulted in $220,900 in training and sequelae costs and 276 cases of PID. Screening by age produced the lowest cost $217,600, over a 1-year period and prevented 222 cases of PID for a cost-savings of $15 per case of PID prevented. Universal testing prevented an additional 11 cases of PID at a cost of $226,400, or costing $800 per additional case of PID prevented over age-targeted screening. Universal treatment prevented an additional 32 cases of PID and cost $221,100, saving $167 per additional cases of PID prevented over universal screening. Over a 2-year period, universal treatment provided the highest cost-savings and prevented the most disease. CONCLUSION: Screening by age provided a cost-savings to the Army over a 1-year period. Other organizations accessing large cohorts of young women could also benefit, even in the short term, from implementation of an age-based chlamydial screening program. Universal testing or universal treatment may be warranted in which long-term societal goals, such as maximum reduction of PID, are relevant.

Adult↗
PubMed1999

Sensitivity and specificity of HIV-1 testing of urine compared with serum specimens: Rakai, Uganda. The Rakai Project Team.

BACKGROUND AND OBJECTIVES: To evaluate a urine HIV-1 test. STUDY DESIGN: Paired urine and blood samples from a sample of 222 subjects were assayed for HIV-1 using Calypte HIV-1 Urine enzyme immunoassay (EIA) with Western blot (WB) confirmation, and sera were tested by EIA and WB. Masked assays were done on stored, refrigerated urine at Johns Hopkins University (JH), and on fresh specimens at the Rakai Project, Entebbe (RP). We assessed the sensitivity and specificity of the urine relative to serum assays. RESULTS: Compliance with provision of urine samples (95.0%) was higher than provision of serum (90.5%). Ninety-six sera were HIV-positive; 92 were HIV-positive on stored urine at JH (sensitivity 95.8%, CI 91.8-99.8%); and 94 (100%) were positive on fresh samples at the RP laboratory (sensitivity = 100.0%). Among serum HIV-negative subjects, all frozen urine were negative at JH and 97.7% of fresh samples were negative at RP. CONCLUSIONS: The Calypte urine HIV-1 EIA with WB is sensitive and specific. In this population, provision of urine was more acceptable than provision of blood samples.

Blood↗
PubMed1999

Ability of the digene hybrid capture II test to identify Chlamydia trachomatis and Neisseria gonorrhoeae in cervical specimens.

The Digene Hybrid Capture II (HCII CT/GC) test is a combination test designed to detect Chlamydia trachomatis and Neisseria gonorrhoeae in a single specimen. It is a nucleic acid hybridization test which uses signal amplification to increase sensitivity. We compared its performance to that of culture on cervical specimens from 1,370 women. Direct fluorescent-antibody assay was used to resolve discrepant results for C. trachomatis. Samples were collected with a proprietary cervical brush or with endocervical swabs. The HCII CT/GC test proved to be sensitive and specific in detecting these organisms. Compared to N. gonorrhoeae culture, it had a sensitivity of 93% (87/94) and a specificity of 98.5% (1,244/1,263). Compared to C. trachomatis culture, the sensitivity was 97.7% (129/132) and specificity was 98.2% (1,216/1,238). Testing of some specimens with discrepant results by PCR suggested that the test would actually prove to be even more specific if it were compared to a nucleic acid amplification test (NAAT). The sensitivity of C. trachomatis culture was somewhat less, at 88.6% (117/132). The endocervical brush appeared to be better than Dacron swabs for collecting specimens. The HCII CT/GC test offers an attractive format that allows simultaneous detection of C. trachomatis and N. gonorrhoeae with a single specimen. An initial positive result is followed by repeat tests with probes to identify chlamydiae or gonococci. This test is more sensitive than C. trachomatis culture and is at least as sensitive as culture for gonococci. It deserves further evaluation and comparison with NAATs and may well offer an attractive alternative for diagnosis and screening of these infections.

Bacteriological Techniques↗
PubMed1999

Evaluation of the digene hybrid capture II CT-ID test for detection of Chlamydia trachomatis in endocervical specimens.

The performance characteristics of the new signal amplification-based Hybrid Capture (HC) II CT-ID test system (Digene, Silver Spring, Md.) with endocervical specimens were compared to those of tissue culture and PCR (AMPLICOR CT PCR; Roche Molecular Systems, Branchburg, N.J.) for detection of Chlamydia trachomatis in 587 women. HC II CT-ID identified 62 of 65 confirmed C. trachomatis-positive patients (sensitivity of 95.4%) and was negative for 517 of 522 patients who were negative by culture and PCR (specificity of 99.0%). Twelve of the 65 confirmed positive patients were negative by culture but were identified by both HC II CT-ID and PCR (sensitivity of culture was 81.5% [P < 0.01]). In comparison, PCR detected 59 of 65 positive specimens (sensitivity of 90.8%) and had a specificity of 99.6% (520 of 522). These results demonstrate that the Digene HC II CT-ID test is a highly sensitive and specific assay for the detection of C. trachomatis infection in endocervical specimens.

Adolescent↗
PubMed1999

Mastitis and immunological factors in breast milk of human immunodeficiency virus-infected women.

Human milk contains important immunological factors that protect the breast from infection and are thought to protect infants from infection, including human immunodeficiency virus (HIV) infection. Human milk immunological factors have not been well characterized in HIV-infected lactating women. Lysozyme, secretory leukocyte protease inhibitor (SLPI), sodium (an indicator of mastitis), and HIV were measured in breast milk of 334 HIV-infected women at 6 weeks postpartum. Women with mastitis, as indicated by elevated breast milk sodium concentrations, had higher median levels lysozyme (290 vs 221 mg/L, p < 0.04), SLPI (38 vs 19 mg/L, p < 0.0001) and HIV (920 copies/mL vs undetectable, p < 0.0001) compared with women without mastitis. Lower total plasma carotenoid levels (p < 0.02) and higher maternal HIV load (p < 0.006) by quartile were risk factors for mastitis. Mastitis, as indicated by elevated breast milk sodium levels, is associated with high concentrations of immunological factors and higher HIV load in breast milk.

Adult↗
PubMed1998

Sex differences in HIV-1 viral load and progression to AIDS.

BACKGROUND: Plasma HIV-1 RNA measurements are used for initiation of antiretroviral treatments. Whether the viral-load association with prognosis is similar in women and men is unknown. METHODS: We studied 812 specimens from 650 injection-drug users (IDUs) participating in a continuous observational study of patients based in a community clinic. HIV-1 load was measured by branched-chain DNA on samples from 527 IDUs from the baseline visit, and by reverse-transcriptase PCR and quantitative microculture on samples from 285 IDUs at a follow-up visit 3 years later. FNDINGS: Women had lower median viral-load measurements than men by branched-chain DNA (3365 vs 8907 copies/mL; p=0.001), reverse-transcriptase PCR (45416 vs 93130 copies/mL; p=0.02), and quantitative microculture (5 vs 8 infectious units per million peripheral blood mononuclear cells; p=0.015). This association remained even after adjustment for CD4 cell count, race, and drug use within the previous 6 months. Time to AIDS was statistically similar for men and women in a univariate proportional-hazards model and in a model adjusting for CD4 cell count. Proportional-hazards models showed that women with the same viral load as men had a 1.6-fold higher risk of AIDS (95% CI 1.10-2.32); or, equivalently, that women with half the viral load of men had a similar time to AIDS as men. INTERPRETATION: Although a biological mechanism remains unclear, these data suggest that current recommendations for HIV-1 viral-load thresholds to initiate antiretroviral therapy should be revised downwards for women.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Chlamydia trachomatis infections in female military recruits.

BACKGROUND: Asymptomatic genital Chlamydia trachomatis infections in women can lead to pelvic inflammatory disease, infertility, and ectopic pregnancy. To design a chlamydia-control program, we conducted a large survey of women in the U.S. military. METHODS: From January 1996 through December 1997, urine samples from 13,204 new female U.S. Army recruits from 50 states were screened by ligase chain reaction for C. trachomatis infection. Information on potential risk factors was obtained by questionnaire. With multivariate analysis, we identified criteria for a screening program. RESULTS: The overall prevalence of chlamydial infection was 9.2 percent, with a peak of 12.2 percent among the 17-year-old recruits. The prevalence was 15 percent or more among the recruits from five southern states. The following risk factors were independently associated with chlamydial infection: having ever had vaginal sex (odds ratio for infection, 5.9), being 25 years of age or less (odds ratio, 3.0), being black (odds ratio, 3.4), having had more than one sex partner in the previous 90 days (odds ratio, 1.4), having had a new partner in the previous 90 days (odds ratio, 1.3), having had a partner in the previous 90 days who did not always use condoms (odds ratio, 1.4), and having ever had a sexually transmitted disease (odds ratio, 1.2). A screening program for subjects 25 years of age or less (87.9 percent of our sample) would have identified 95.3 percent of the infected women. CONCLUSIONS: Among female military recruits, the prevalence of chlamydial infection is high. A control program that screens female recruits who are 25 years old or younger with urine DNA-amplification assays has the potential to reduce infection, transmission, and the sequelae of chlamydial infection.

Adolescent↗
PubMed1998

Incident Chlamydia trachomatis infections among inner-city adolescent females.

CONTEXT: Adolescents are at highest risk for infection with Chlamydia trachomatis, an important preventable cause of pelvic inflammatory disease and subsequent tubal factor infertility in US women. Current guidelines for delivery of adolescent primary care services recommend yearly chlamydia screening for those adolescent females considered to be at risk. OBJECTIVES: To describe the epidemiology of prevalent and incident chlamydia infection among adolescent females to assess the appropriate interval for chlamydia screening and to define risk factors that would identify adolescent females to target for screening. DESIGN: Prospective longitudinal study. PATIENTS: A consecutive sample of 3202 sexually active females 12 through 19 years old making 5360 patient visits over a 33-month period, January 1994 through September 1996. SETTING: Baltimore, Md, family planning, sexually transmitted disease, and school-based clinics. INTERVENTION: Testing for C trachomatis by polymerase chain reaction. MAIN OUTCOME MEASURES: Prevalence and incidence of C trachomatis infections; predictors of positive test result for C trachomatis. RESULTS: Chlamydia infection was found in 771 first visits (24.1%) and 299 repeat visits (13.9%); 933 adolescent females (29.1%) had at least 1 positive test result. Females who were 14 years old had the highest age-specific chlamydia prevalence rate (63 [27.5%] of 229 cases; P=.01). The chlamydia incidence rate was 28.0 cases per 1000 person-months (95% confidence interval, 24.9-31.5 cases). The median time was 7.2 months to a first positive chlamydia test result and 6.3 months to a repeat positive test result among those with repeat visits. Independent predictors of chlamydia infection--reason for clinic visit, clinic type, prior sexually transmitted diseases, multiple or new partners, or inconsistent condom use-failed to identify a subset of adolescent females with the majority of infections. CONCLUSIONS: A high prevalence and incidence of C trachomatis infection were found among adolescent females. We, therefore, recommend screening all sexually active adolescent females for chlamydia infection every 6 months, regardless of symptoms, prior infections, condom use, or multiple partner risks.

Adolescent↗
PubMed1998

A randomized, community trial of intensive sexually transmitted disease control for AIDS prevention, Rakai, Uganda.

OBJECTIVE: To describe the design and first-round survey results of a trial of intensive sexually transmitted disease (STD) control to reduce HIV-1 incidence. STUDY DESIGN: Randomized, controlled, community-based trial in Rakai District, Uganda. METHODS: In this ongoing study, 56 communities were grouped into 10 clusters designed to encompass social/sexual networks; clusters within blocks were randomly assigned to the intervention or control arm. Every 10 months, all consenting resident adults aged 15-59 years are visited in the home for interview and sample collection (serological sample, urine, and, in the case of women, self-administered vaginal swabs). Sera are tested for HIV-1, syphilis, gonorrhea, chlamydia, trichomonas and bacterial vaginosis. Following interview, all consenting adults are offered directly observed, single oral dose treatment (STD treatment in the intervention arm, anthelminthic and iron-folate in the control arm). Treatment is administered irrespective of symptoms or laboratory testing (mass treatment strategy). Both arms receive identical health education, condom and serological counseling services. RESULTS: In the first home visit round, the study enrolled 5834 intervention and 5784 control arm subjects. Compliance with interview, sample collection and treatment was high in both arms (over 90%). Study arm populations were comparable with respect to sociodemographic and behavioral characteristics, and baseline HIV and STD rates. The latter were high: 16.9% of all subjects were HIV-positive, 10.0% had syphilis, and 23.8% of women had trichomonas and 50.9% had bacterial vaginosis. CONCLUSIONS: Testing the effects of STD control on AIDS prevention is feasible in this Ugandan setting.

Acquired Immunodeficiency Syndrome↗
PubMed1998

HIV-1 DNA shedding in genital ulcers and its associated risk factors in Pune, India.

HIV infection status was determined in 302 consecutive patients with genital ulcer disease (GUD) presenting to two sexually transmitted disease (STD) clinics in Pune, India. Of the 71 (24%) individuals with HIV infection, 67 (94%) were HIV antibody-positive, and 4 (6%) were HIV antibody-negative but p24 antigen-positive at the time of presentation. HIV-1 DNA was detected in 24 (34%) specimens. The genital ulcers of all four acutely infected p24-antigenemic subjects were HIV-1 DNA-positive by polymerase chain reaction (PCR) assay, compared with 20 of 67 (30%) seropositive patients (p = .01). Presence of chancroid, GUD symptoms for > 10 days, and concurrent diagnosis of cervicitis or urethritis were significantly associated risk factors for HIV-1 DNA shedding in ulcers. Early GUD diagnosis and aggressive treatment of HIV-infected patients may significantly reduce secondary transmission of HIV to other sex partners.

Adolescent↗