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ABSTRACTAccurate point-of-care (POC) diagnostic tests for Chlamydia trachomatisinfection are urgently needed for the rapid treatment of patients. In a blind comparative study, we evaluated microwave-accelerated metal-enhanced fluorescence (MAMEF) assays for ultrafast and sensitive detection of C. trachomatisDNA from vaginal swabs. The results of two distinct MAMEF assays were compared to those of nucleic acid amplification tests (NAATs). The first assay targeted the C. trachomatis16S rRNA gene, and the second assay targeted the C. trachomatiscryptic plasmid. Using pure C. trachomatis, the MAMEF assays detected as few as 10 inclusion-forming units/ml of C. trachomatisin less than 9 min, including DNA extraction and detection. A total of 257 dry vaginal swabs from 245 female adolescents aged 14 to 22 years were analyzed. Swabs were eluted with water, the solutions were lysed to release and to fragment genomic DNA, and MAMEF-based DNA detection was performed. The prevalence of C. trachomatisby NAATs was 17.5%. Of the 45 samples that were C. trachomatispositive and the 212 samples that were C. trachomatisnegative by NAATs, 33/45 and 197/212 were correctly identified by the MAMEF assays if both assays were required to be positive (sensitivity, 73.3%; specificity, 92.9%). Using the plasmid-based assay alone, 37/45 C. trachomatis-positive and 197/212 C. trachomatis-negative samples were detected (sensitivity, 82.2%; specificity, 92.9%). Using the 16S rRNA assay alone, 34/45 C. trachomatis-positive and 197/212 C. trachomatis-negative samples were detected (sensitivity, 75.5%; specificity, 92.9%). The overall rates of agreement with NAAT results for the individual 16S rRNA and cryptic plasmid assays were 89.5% and 91.0%, respectively. Given the sensitivity, specificity, and rapid detection of the plasmid-based assay, the plasmid-based MAMEF assay appears to be suited for clinical POC testing.

Point-of-care (POC) tests are an important strategy to address the epidemic of sexually transmitted infections (STIs) among both adolescents and young adults. Although access to care and confidentiality are major barriers to STI care, POC tests allow the clinician to provide immediate and confidential test results and treatment. In addition, POC test results constitute a teachable moment; that is, an opportunity to provide immediate feedback to the patient that may impact his/her risk behaviors. This paper reviews published data and manufacturer's product literature describing current POC STI tests, including studies of test performance and impact on treatment intervals and disease spread. It presents theoretical and proposed pitfalls and solutions of implementing POC tests in clinical and nontraditional settings and home care venues. We reviewed the available STI tests according to the World Health Organization criteria for judging POC tests the affordable, sensitive, specific, user-friendly, rapid and robust, equipment-free, and delivered fscriteria.

Reproduction was studied in male C57B/6 mice treated with contaminated soils from a 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) manufacturing site in Newark, New Jersey, and a metal scrap yard where equipment from the manufacturing site was recycled. The soils contained a wide variety of contaminants including 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). Treated males were mated to females given decontaminated soil. No acute toxicity was observed in treated males. 2,3,7,8-TCDD (up to 90 µg/kg) or 2,3,7,8-TCDD from the contaminated soils (up to 288 µg/kg) had no adverse effect on reproduction when the male mouse was treated. However, treatment of males with soil from the 2,4,5-T manufacturing site was associated with a marked decrease in viable litters at whelping and a decrease in pup survival. This toxicity may be associated with TCDD in combination with other toxic compounds that are present on the soil.

Reproduction in female C57B/6 mice treated with contaminated soils from a 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) manufacturing site and a metal scrap yard in Newark, New Jersey was studied. Soils contained a wide variety of contaminants, including halogenated dibenzodioxins and dibenzofurans, benzene, alkylbenzenes, chlorobenzenes, polyaromatic hydrocarbons, phenolics, phenoxy acids and other compounds. Acute and reproductive toxicity (primarily fewer live pups born and fewer pups surviving until weaning) was observed from the manufacturing site soil (soil A; with 2,050 µg 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD)/kg soil and 18 mg total dibenzodioxins and dibenzofurans/kg soil); the scrap yard soil (soil B; with 230 (µg 2,3,7,8-TCDD/kg soil) had no observable effect. Soil recontaminated with 2,3,7,8-TCDD, or 2,3,7,8-TCDD in corn oil interfered with estrus cycling and completely prevented reproduction. If 2,3,7,8-TCDD treatment was terminated, estrus cycling resumed within four weeks, but reproduction was still unsuccessful for these mice. The results suggest that 1) the manufacturing site soil (soil A) is toxic but the signs of toxicity cannot be solely attributed to the 2,3,7,8-TCDD content; 2) even though the bioavailability of 2,3,7,8-TCDD from this soil is low (Umbreitet al. 1986), other reproductive toxins are bioavailable or the low doses of 2,3,7,8-TCDD that are bioavailable may be sufficient to be reproductive toxins; 3) 2,3,7,8-TCDD blocks estrus in mice and (as previously reported) interferes with reproduction; and 4) after cessation of dosing, thein situ concentrations of 2,3,7,8-TCDD that block estrus are decreased below an effective level within four weeks.