Tissue formation and host remodeling of an elastomeric biodegradable scaffold in an ovine pulmonary leaflet replacement model.

In pursuit of a suitable scaffold material for cardiac valve tissue engineering applications, an acellular, electrospun, biodegradable polyester carbonate urethane urea (PECUU) scaffold was evaluated as a pulmonary valve leaflet replacement in vivo. In sheep (n = 8), a single pulmonary valve leaflet was replaced with a PECUU leaflet and followed for 1, 6, and 12 weeks. Implanted leaflet function was assessed in vivo by echocardiography. Explanted samples were studied for gross pathology, microscopic changes in the extracellular matrix, host cellular re-population, and immune responses, and for biomechanical properties. PECUU leaflets showed normal leaflet motion at implant, but decreased leaflet motion and dimensions at 6 weeks. The leaflets accumulated α-SMA and CD45 positive cells, with surfaces covered with endothelial cells (CD31+). New collagen formation occurred (Picrosirius Red). Accumulated tissue thickness correlated with the decrease in leaflet motion. The PECUU scaffolds had histologic evidence of scaffold degradation and an accumulation of pro-inflammatory/M1 and anti-inflammatory/M2 macrophages over time in vivo. The extent of inflammatory cell accumulation correlated with tissue formation and polymer degradation but was also associated with leaflet thickening and decreased leaflet motion. Future studies should explore pre-implant seeding of polymer scaffolds, more advanced polymer fabrication methods able to more closely approximate native tissue structure and function, and other techniques to control and balance the degradation of biomaterials and new tissue formation by modulation of the host immune response.

Good performance of rapid prostate-specific antigen test for detection of semen exposure in women: implications for qualitative research.

BACKGROUND: Prostate-specific antigen (PSA) is a valid biomarker of semen exposure in women and has been used to assess reliability of self-reported sexual behavior as well as serve as a proxy measure for condom efficacy. Quantitative PSA tests are expensive and require specialized equipment. A simple, rapid, and inexpensive test for PSA would facilitate semen biomarker evaluation in a variety of research settings. This study evaluated the performance of a rapid PSA test compared with a quantitative assay to identify semen in vaginal swab specimens. METHODS: We tested 581 vaginal swabs collected from 492 women participating in 2 separate research studies in Bangladesh and Zimbabwe. PSA in vaginal secretions was detected using the quantitative IMx (Abbott Laboratories) assay and the ABAcard p30 (Abacus Diagnostics) rapid immunochromatographic strip test. RESULTS: The ABAcard test was 100% sensitive (95% confidence interval [CI], 98%-100%) and 96% specific (95% CI, 93%-97%) compared with the quantitative test in detecting >1.0 ng PSA/mL vaginal swab eluate. Rapid PSA results were semiquantitative and correlated well with PSA concentrations (kappa = 0.88; 95% CI, 0.85-0.90). CONCLUSION: Rapid PSA detection requires no instrumentation and can be performed easily and economically. Having rapid PSA results available immediately following interview provides opportunities to explore discrepancies between the objective marker of recent semen exposure and self-reported behaviors.

Flow Preservation of Umbilical Vein for Autologous Shunt and Cardiovascular Reconstruction.

BACKGROUND: Synthetic graft materials are commonly used for shunts and cardiovascular reconstruction in neonates, but are prone to thrombosis and scarring. The umbilical vein is a potential source of autologous, endothelialized tissue for neonatal shunts and tissue reconstruction, but requires preservation before implantation. METHODS: Umbilical cords were collected in UW solution with antibiotics at 4°C until dissection. Umbilical vein segments were tested for burst pressure before and after 2 weeks of preservation. Umbilical veins segments were preserved under static or flow conditions at 4°C in UW solution with 5% human plasma lysate for 7 days. Veins were evaluated with histopathology, scanning electron microscopy, and platelet adhesion testing. RESULTS: Umbilical veins have no difference in burst pressure at harvest (n = 16) compared with 2 weeks of preservation (n = 11; 431 ± 229 versus 438 ± 244 mm Hg). After 1 week, static and flow-preserved veins showed viability of the vessel segments with endothelium staining positive for CD31, von Willebrand factor, and endothelial nitric oxide synthase. Scanning electron microscopy demonstrated preservation of normal endothelial morphology and flow alignment in the flow-preserved samples compared with cobblestone endothelial appearance and some endothelial cell loss in the static samples. Static samples had significantly more platelet adhesion than flow-preserved samples did. CONCLUSIONS: Umbilical veins have adequate burst strength to function at neonatal systemic pressures. Preservation under flow conditions demonstrated normal endothelial and overall vascular morphology with less platelet adhesion compared with static samples. Preserved autologous umbilical veins are potential source for endothelialized shunts or cardiovascular repair tissue for neonates.

Rapid antigen testing compares favorably with transcription-mediated amplification assay for the detection of Trichomonas vaginalis in young women.

BACKGROUND: Diagnosis of Trichomonas vaginalis (TV) infection is limited by imperfect testing methods. Newer tests, such as rapid antigen and nucleic acid amplification tests, are often compared with culture, which is not widely used but is more sensitive than wet mount. We assessed the sensitivity and specificity of 4 tests for the identification of TV using 3 statistical approaches. METHODS: Sexually active adolescent women aged 14-21 years (n=330) were recruited from a teen health center and emergency department. Vaginal swabs were tested for TV using wet mount, culture (InPouch TV; Biomed Diagnostics), rapid antigen testing (OSOM TV; Genzyme Diagnostics), and transcription-mediated amplification testing (TMA; APTIMA TV analyte specific reagents; Gen-Probe). RESULTS: TV was detected in 61 participants (18.5%). Compared with a composite reference standard (i.e., any TV test with positive results), the sensitivities of wet mount, culture, rapid antigen testing, and TMA were 50.8%, 75.4%, 82%, and 98.4%, respectively. Using latent class analysis, the sensitivity of wet mount (56%) was significantly lower than that of other tests, and the sensitivities of culture and rapid antigen testing were similar (83% and 90%, respectively); specificity was 100% for each of these 3 methods. TMA had a sensitivity of 98.2% and a specificity of 98%. Tests performed equally well regardless of whether the participant had bleeding or other infections. The sensitivities of the rapid antigen test and TMA were comparable (92.5% and 97.5%, respectively) in women who had vaginal symptoms. CONCLUSIONS: Wet mount alone is insufficient for the reliable diagnosis of TV infection in women. TMA and rapid antigen tests are highly sensitive and specific, and both are superior to wet mount. Rapid antigen testing is equivalent to culture, and it compares favorably with the sensitivity of TMA for the detection of TV.

Vaginal swab specimen processing methods influence performance of rapid semen detection tests: a cautionary tale.

BACKGROUND: Detection of semen biomarkers in vaginal fluid can be used to assess women's recent exposure to semen. Quantitative tests for detection of prostate-specific antigen (PSA) perform well, but are expensive and require specialized equipment. We assessed two rapid immunochromatographic strip tests for identification of semen in vaginal swabs. STUDY DESIGN: We tested 581 vaginal swabs collected from 492 women. Vaginal secretions were eluted into saline, and PSA was measured using the quantitative IMx (Abbott Laboratories, Abbott Park, IL, USA) assay. Specimens were also tested using the ABAcard p30 test (Abacus Diagnostics, West Hills, CA, USA) for detection of PSA and RSID-Semen test (Independent Forensics, Hillside, IL, USA) for detection of semenogelin (Sg). RESULTS: Vaginal swab extraction using saline was compatible with direct assessment of vaginal swab eluates using ABAcard for PSA detection, but not for Sg detection using RSID. The rapid PSA test detected 91% of specimens containing semen compared to 74% by the rapid Sg test. CONCLUSION: Investigators are urged to optimize vaginal swab specimen preparation methods for performance of RSID or other tests to detect semen components other than PSA. Previously described methods for PSA testing are not uniformly applicable to other tests.

Mycoplasma genitalium detected by transcription-mediated amplification is associated with Chlamydia trachomatis in adolescent women.

OBJECTIVES: The clinical significance of Mycoplasma genitalium (MG) infection in adolescent women is poorly understood. We compared the prevalence of MG with that of other sexually transmitted organisms such as Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Trichomonas vaginalis (TV) and assessed the associations of MG with sexual behaviors, genitourinary symptoms, physical and laboratory findings. STUDY DESIGN: Women aged 14 to 21 years (n = 331) were recruited from an urban medical center. The subjects' sexual behaviors, genitourinary symptoms, and physical findings were recorded. Endocervical swabs were collected for CT and NG testing and vaginal swabs for wet mount, Gram stain, TV and MG testing. MG infection was identified by nucleic acid amplification using a transcription-mediated amplification assay. RESULTS: MG was detected in 74 (22.4%), CT in 79 (24.4%), TV in 60 (18.2%), and NG in 35 (10.7%) subjects. MG infection was not associated with vaginal symptoms, physical evidence of cervicitis, or findings on wet mount or Gram stain. In logistic regression, variables positively associated with MG were current CT [odds ratio (OR), 2.3; 95% confidence interval (CI), 1.4-4.4] and recent sexual contact (< or =7 days) (OR, 2.0; CI, 1.1-3.2). Dysuria (OR, 0.44; CI, 0.2-0.96) and use of hormonal contraception (OR, 0.55; CI, 0.3-1.0) were negatively associated with MG infection. CONCLUSION: In adolescent women, MG infection was as common as chlamydial infection and trichomoniasis and more common than gonorrhea. MG was associated with CT and recent sexual contact but not with vaginal symptoms or signs of cervicitis.