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A simple, rapid chemical coating and patterning method was developed and optimized for paper-based substrates for use in paper spray mass spectrometry (PS-MS). A variety of chlorosilanes were explored for coating paper substrates, and their effectiveness in forming hydrophobic surfaces was characterized via contact angle goniometry, scanning electron microscopy, and energy dispersive X-ray spectroscopy. Trichloromethylsilane was selected as the primary coating agent because of the short time required to produce a hydrophobic surface (contact angle > 130°), as well as the ease of patterning. Patterning was performed using 3D-printed masks and an oxygen/plasma cleaner. Optimal mask thickness and oxygen/plasma cleaning parameters were determined to produce channels varying from 0.5 to 2.5 mm in width. The effectiveness of the patterned substrates for PS-MS was determined via analysis of four antiretrovirals: emtricitabine, lamivudine, efavirenz, and dolutegravir. Calibration curves were made for each antiretroviral at varying channel widths, and the limits of detection and limits of quantification for each drug were determined. These results show that this patterning method results in an average 7.2-fold improvement in sensitivity and an average 190-fold improvement in limits of detection over uncoated paper substrates in a neat matrix. In a proof-of-concept experiment, calibration curves were generated for each antiretroviral in urine. A patterned paper substrate with a 2-mm channel resulted in an average 7.4-fold improvement in sensitivity and an average 18-fold improvement in limits of detection over uncoated paper substrates.

The quantum spin properties of nitrogen-vacancy defects in diamond enable diverse applications in quantum computing and communications 1 . However, fluorescent nanodiamonds also have attractive properties for in vitro biosensing, including brightness 2 , low cost 3 and selective manipulation of their emission 4 . Nanoparticle-based biosensors are essential for the early detection of disease, but they often lack the required sensitivity. Here we investigate fluorescent nanodiamonds as an ultrasensitive label for in vitro diagnostics, using a microwave field to modulate emission intensity 5 and frequency-domain analysis 6 to separate the signal from background autofluorescence 7 , which typically limits sensitivity. Focusing on the widely used, low-cost lateral flow format as an exemplar, we achieve a detection limit of 8.2 × 10 -19 molar for a biotin-avidin model, 10 5  times more sensitive than that obtained using gold nanoparticles. Single-copy detection of HIV-1 RNA can be achieved with the addition of a 10-minute isothermal amplification step, and is further demonstrated using a clinical plasma sample with an extraction step. This ultrasensitive quantum diagnostics platform is applicable to numerous diagnostic test formats and diseases, and has the potential to transform early diagnosis of disease for the benefit of patients and populations.

Background: Electronic patient-reported outcomes (PRO) provide quick and usually reliable assessments of patients' health-related quality of life (HRQL)., Objective: An electronic version of the Patient-Reported Outcomes Quality of Life-human immunodeficiency virus (PROQOL-HIV) questionnaire was developed, and its face validity and reliability were assessed using standard psychometric methods., Methods: A sample of 80 French outpatients (66% male, 52/79; mean age 46.7 years, SD 10.9) were recruited. Paper-based and electronic questionnaires were completed in a randomized crossover design (2-7 day interval). Biomedical data were collected. Questionnaire version and order effects were tested on full-scale scores in a 2-way ANOVA with patients as random effects. Test-retest reliability was evaluated using Pearson and intraclass correlation coefficients (ICC, with 95% confidence interval) for each dimension. Usability testing was carried out from patients' survey reports, specifically, general satisfaction, ease of completion, quality and clarity of user interface, and motivation to participate in follow-up PROQOL-HIV electronic assessments., Results: Questionnaire version and administration order effects (N=59 complete cases) were not significant at the 5% level, and no interaction was found between these 2 factors (P=.94). Reliability indexes were acceptable, with Pearson correlations greater than .7 and ICCs ranging from .708 to .939; scores were not statistically different between the two versions. A total of 63 (79%) complete patients' survey reports were available, and 55% of patients (30/55) reported being satisfied and interested in electronic assessment of their HRQL in clinical follow-up. Individual ratings of PROQOL-HIV user interface (85%-100% of positive responses) confirmed user interface clarity and usability., Conclusions: The electronic PROQOL-HIV introduces minor modifications to the original paper-based version, following International Society for Pharmacoeconomics and Outcomes Research (ISPOR) ePRO Task Force guidelines, and shows good reliability and face validity. Patients can complete the computerized PROQOL-HIV questionnaire and the scores from the paper or electronic versions share comparable accuracy and interpretation.

Background: A bridging study was performed to compare the safety, dose delivery, and acceptability of a prefilled plastic and user-filled paper applicator to assess whether a low-cost, user-filled, paper applicator could serve as a delivery option for tenofovir (TFV) 1% vaginal microbicide gel., Methods: The study used a randomized crossover design with 25 healthy women randomized to begin with the prefilled or user-filled applicator. Within each study arm, participants delivered two 4.0-mL doses of TFV 1% gel vaginally for 7 days, with one dose delivered at the clinic each morning and a second dose delivered at home each evening. To assess the primary objective, applicator safety, colposcopy examinations were performed at 2 time points in each study arm., Results: There were no colposcopic findings or adverse events attributable to either applicator. One case of vulvovaginal candidiasis was considered possibly related to gel use. On average, the user-filled applicator delivered 96% of the target dose, with 85% of doses falling within ± 10% of the average dose volume. Participants found both applicators comparable for ease of use, insertion, and dispensing gel, with 60% of participants preferring the user-filled applicator., Conclusions: This study suggests that both applicators are safe, and most women delivered TFV with the user-filled applicator as directed. Participants found both applicators acceptable, with a slight majority preferring the user-filled applicator. Incorporating a low-cost, user-filled, paper applicator to deliver TFV could help reduce costs and improve access to TFV 1% gel, especially in resource-limited settings heavily impacted by HIV.

Objectives: to determine the seroprevalence rate of toxoplasmosis, HIV, syphilis and rubella in a population of puerperal women., Methods: a prospective, cross-sectional study was performed from February 2007 to April 2008 at Hospital Geral, Universidade de Caxias do Sul in a population of 1,510 puerperal women. Women that gave birth to live born or stillborn infants were included in the study; maternal and perinatal variables were analyzed. Descriptive statistics and Pearson's chi-square with occasional Fisher's correction were used for comparisons. Alpha was set in 5%., Results: a total of 148 cases of congenital infection (9.8%) were identified: 66 cases of syphilis (4.4%), 40 cases of HIV (2.7%), 27 cases of toxoplasmosis (1.8%) and 15 cases of rubella (1.0%). In ten cases there was co-infection (four cases of HIV and syphilis, two cases of HIV and rubella, one case of HIV and toxoplasmosis, two cases of rubella and syphilis, and one case of toxoplasmosis and rubella). In a comparison between puerperal women with and without infection there was no statistical significance in relation to incidence of abortions, small for gestational age, prematurity, live births and stillbirths, and prenatal care. Need of neonatal intensive care unit (NICU), maternal schooling, maternal age higher than 35 years and drug use (alcohol, cocaine and crack) had statistical significance., Conclusion: the prevalence rate of infections was 9.8%. Need of NICU, maternal schooling lower than eight years, maternal age higher than 35 years and drug use were significantly associated with occurrence of congenital infection.

The stability of human immunodeficiency virus type 1 (HIV-1) DNA in whole blood collected on filter paper (FTA Card) was evaluated. After >4 years of storage at room temperature in the dark our qualitative assay detected virus at a rate similar to that of our initial test (58 of 60, 97%; P = 0.16), suggesting long-term HIV-1 DNA stability.

The use of dried blood spots lends itself to widespread application in large field studies, especially in remote areas. We present experience gained during a perinatal HIV transmission study in southern Africa in which dried blood spot samples were used for polymerase chain reaction (PCR) tests. In this study, 15,810 filter paper cards with dried blood spots were collected. Infants were seen at age 6 and 12 weeks, and PCR was routinely done in duplicate on each sample. Of 186 negative controls (infants born to HIV-negative women), two (1.1%) had a single strongly reactive PCR result; the repeated duplicates were both negative. In contrast, all 24 known positive samples were strongly positive in both tests. Results were available from 1,976 duplicate tests on 1,235 infants born to HIV-infected women. Based on the PCR result on a later sample, the positive predictive value was 97.6% if both replicates were strongly positive (absorbance: 0.8 OD450 U), 100% when one of the replicates was strongly positive, and 27% when one or both replicates were weakly positive (but none strongly positive). When both replicates were negative, the negative predictive value was > or = 96.2%. Thus, when a single HIV PCR test has a strongly positive result, the infant is very likely to be infected. A positive PCR result after age 1 month was 98.9% accurate in predicting antibody positivity after 15 months. Suggestions for sample collection, storage, and PCR testing are provided.

A method for detection of proviral human immunodeficiency virus DNA in dried blood spots on filter paper by direct polymerase chain reaction (PCR) has been developed. To develop the method, a standard system was used which was prepared from cells each containing a single integrated provirus and titrated with normal donor blood. This rapid procedure provides virtually quantitative yields of nuclear DNA and exploits most of the standard methodology described for blood specimens. A nested PCR using SK38-SK39 gag as the internal primer pair was also designed; this PCR detected a single copy of provirus per filter at near theoretical frequency with SK19 probe. The utility of the procedure was demonstrated with clinical specimens. Blood spot filters from human immunodeficiency virus-infected and uninfected individuals were readily and unequivocally discriminated. The method is designed for ultimate use with large (1.5-ml) sample preparation tubes that are compatible as PCR tubes with thermal cyclers. This will permit convenient, direct single-tube PCR of dried blood specimens on filters. It should be adaptable to analysis of dried blood spots for a variety of infectious or genetic diseases.