Performance characteristics of the boson rapid SARS-cov-2 antigen test card vs RT-PCR: Cross-reactivity and emerging variants.

Background: SARS-CoV-2 virus has undergone several mutations on its genome, since the onset of the pandemic. Multiple variants of concern (VOC) have emerged including Alpha, Beta, Gamma, and Delta with the more recent one being the Omicron (B.1.1.529). Specific rapid antigen tests (RADs) have been used for the detection of SARS-CoV-2. However, since the emergence of new VOCs, the performance characteristics of these RADs needs to be re-evaluated. Objectives: The main purposes of this clinical study were to determine the diagnostic sensitivity and specificity of the BOSON Rapid Antigen Test compared to the gold standard real time RT-PCR and to determine the ability of the RAD to accurately depict different VOC. Additionally, the cross reactivity to other viruses and pathogen, as well as, the possible interference of non Covid-19 hospitalized patients for various causes, were investigated. Results: A total of 623 individuals (symptomatic) were tested. The sensitivity, specificity and accuracy of the BOSON RAD was 95.27%, 100% and 98.45% (n = 448), meeting the WHO recommended standards. Additionally, the Delta (83.33%, Ct < 34) and Omicron (100%, Ct < 26) VOC were determined with high sensitivity. Also, there was no interference from hospitalized, non-Covid 19 patients, and no cross-reactivity was detected. Conclusions: The study showed that this RAD could rapidly identify individuals with SARS-CoV-2, including those with the new dominant Omicron VOC, with no cross reactivity from other pathogens.

Detection of Chlamydia trachomatis inside spermatozoa using flow cytometry: Effects of antibiotic treatment (before and after) on sperm count parameters.

There is increasing evidence that Chlamydia trachomatis (CT) infection can directly affect male fertility. However, only few have investigated the effects of CT on semen parameters, and mostly with inconclusive results. The main aims of this study were to identify CT inside spermatozoa, and the possible pre and post antibiotic treatment effects on the overall semen parameters. We developed a flow cytometric method for the detection of CT inside spermatozoa (SPI™). Briefly, sperm cells were fixed, membrane permeabilized and DNA was loosened using DNAse. Sperm cells were incubated with a primary monoclonal antibody against CT and with a secondary fluorescent antibody (vs primary), and analysed using a flow cytometer. Of 2415 infertile individuals, 48.61% were found positive for CT. 170 CT+ samples were included in the CT antibiotic treatment study. 78.82% (134/170) of the CT+ showed a significant reduction in the percentage of the iCT infected spermatozoa after the antibiotic treatment; 59.70% (80/134) decreased to non-detectable levels. Spermcount data were also recorded. Spermatozoa morphology (normal and teratozoospermia index, TZI) and motility (fast progressive and non-progressive spermatozoa) were statistically significant altered in CT+ pre-treatment vs control group. CT antibiotic treatment showed statistically significant effects on normal spermatozoa morphology, mid-piece and tail defects, and TZI. The study demonstrated that semen flow cytometric analysis of semen could be a valuable tool for faster and accurate identification of individuals with asymptomatic CT infection. It also identified a positive effect of antibiotic therapy on semen parameters, that could help males with infertility.

Evaluation of the Boson rapid Ag test vs RT-PCR for use as a self-testing platform.

The gold standard test available for detecting COVID-19 patients is Real Time RT-PCR. However, this method is expensive, needing special equipment and skilled laboratory staff. Recently, less expensive antigen tests have become available, that could easily and rapidly identify new COVID-19 cases. Our objective was to evaluate the Boson Rapid Antigen Test Card versus the RT-rtPCR, using samples taken both by laymen (self-testing) and professionals. The sensitivity, specificity and accuracy rates were, 98.18%, 100.00%, and 99.28%, respectively. The positive and negative predictive values were 100.00% and 98.82%, respectively. The detection rate for asymptomatic patients was 90.48%, and detection rate for Ct values ≥30 was 91.67%. Our results indicate a high coincidence rate between the Boson and the referencing RT-rtPCR method, meeting the performance standards recommended by the WHO. Therefore, this test could facilitate a fast self-testing screening method, for the detection of infected individuals.

Dyslexic participants show intact spontaneous categorization processes.

We examine the performance of dyslexic participants on an unsupervised categorization task against that of matched non-dyslexic control participants. Unsupervised categorization is a cognitive process critical for conceptual development. Existing research in dyslexia has emphasized perceptual tasks and supervised categorization tasks (for which intact attentional processes are paramount), but there have been no studies on unsupervised categorization. Our investigation was based on Pothos and Chater's (Cognit. Sci., 2002; 26: 303-343) model of unsupervised categorization and the corresponding methodology for analysing results. Across all performance indices and various data-processing options, we could identify no difference between dyslexic and non-dyslexic participants.

The cognitive bases of learning to read and spell in Greek: evidence from a longitudinal study.

We conducted a longitudinal study examining the role of phonemic awareness, phonological processing, and grammatical skills in the development of reading and spelling abilities in Greek. A battery of cognitive, linguistic, and literacy tasks was administered to 131 primary school children (65 7-year-olds and 66 9-year-olds) and was repeated in the following year (8- and 10-year-olds, respectively). Phoneme awareness, speech rate, and rapid automatized naming (RAN) were concurrent predictors of reading rate at Time 1 (T1), and speech rate was a longitudinal predictor of reading rate at Time 2 (T2) when reading at T1 was controlled. The predictors of spelling differed from those of reading; phoneme awareness and speech rate predicted concurrent attainments at T1, and phoneme awareness was a robust longitudinal predictor. Despite the differences in the degree of transparency between the Greek and English orthographies, phoneme awareness predicts variations in learning to read and spell in both languages.