Performance of a Point of Care Test for Detecting IgM and IgG Antibodies Against SARS-CoV-2 and Seroprevalence in Blood Donors and Health Care Workers in Panama.

Novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic, which has reached 28 million cases worldwide in 1 year. The serological detection of antibodies against the virus will play a pivotal role in complementing molecular tests to improve diagnostic accuracy, contact tracing, vaccine efficacy testing, and seroprevalence surveillance. Here, we aimed first to evaluate a lateral flow assay's ability to identify specific IgM and IgG antibodies against SARS-CoV-2 and second, to report the seroprevalence estimates of these antibodies among health care workers and healthy volunteer blood donors in Panama. We recruited study participants between April 30th and July 7th, 2020. For the test validation and performance evaluation, we analyzed serum samples from participants with clinical symptoms and confirmed positive RT-PCR for SARS-CoV-2, and a set of pre-pandemic serum samples. We used two by two table analysis to determine the test positive and negative percentage agreement as well as the Kappa agreement value with a 95% confidence interval. Then, we used the lateral flow assay to determine seroprevalence among serum samples from COVID-19 patients, potentially exposed health care workers, and healthy volunteer donors. Our results show this assay reached a positive percent agreement of 97.2% (95% CI 84.2-100.0%) for detecting both IgM and IgG. The assay showed a Kappa of 0.898 (95%CI 0.811-0.985) and 0.918 (95% CI 0.839-0.997) for IgM and IgG, respectively. The evaluation of serum samples from hospitalized COVID-19 patients indicates a correlation between test sensitivity and the number of days since symptom onset; the highest positive percent agreement [87% (95% CI 67.0-96.3%)] was observed at ≥15 days post-symptom onset (PSO). We found an overall antibody seroprevalence of 11.6% (95% CI 8.5-15.8%) among both health care workers and healthy blood donors. Our findings suggest this lateral flow assay could contribute significantly to implementing seroprevalence testing in locations with active community transmission of SARS-CoV-2.

Cell-Based Therapy for the Treatment of Glioblastoma: An Update from Preclinical to Clinical Studies.

Glioblastoma (GB), an aggressive primary tumor of the central nervous system, represents about 60% of all adult primary brain tumors. It is notorious for its extremely low (~5%) 5-year survival rate which signals the unsatisfactory results of the standard protocol for GB therapy. This issue has become, over time, the impetus for the discipline of bringing novel therapeutics to the surface and challenging them so they can be improved. The cell-based approach in treating GB found its way to clinical trials thanks to a marvelous number of preclinical studies that probed various types of cells aiming to combat GB and increase the survival rate. In this review, we aimed to summarize and discuss the up-to-date preclinical studies that utilized stem cells or immune cells to treat GB. Likewise, we tried to summarize the most recent clinical trials using both cell categories to treat or prevent recurrence of GB in patients. As with any other therapeutics, cell-based therapy in GB is still hampered by many drawbacks. Therefore, we highlighted several novel techniques, such as the use of biomaterials, scaffolds, nanoparticles, or cells in the 3D context that may depict a promising future when combined with the cell-based approach.

Vascular biomarkers and ApoE4 expression in mild cognitive impairment and Alzheimer's disease.

Vascular pathology and genetic markers such as apolipoprotein E allele ε4 (ApoE ε4) are risk factors for the progression from mild cognitive impairment (MCI) to Alzheimer's disease (AD). In Panama, a high prevalence of vascular risk factors and an increase in the aging population, generate the need to investigate biomarkers using specific, sensitive, non-invasive and cost-efficient methods that could be used in primary care. The main objective of this study was to explore the association between vascular biomarkers such as intima-media thickness (IMT) and stenosis, ApoΕ Îµ4 and cognitive function in a sample of older adults, including healthy controls (n = 41), MCI (n = 33), and AD (n = 12). A descriptive and cross-sectional study was conducted. Participants were part of the Panama Aging Research Initiative (PARI), the first prospective study in aging in Panama. Assessments included a neuropsychological battery, ApoΕ Îµ4 genotyping and a Doppler ultrasound of the left carotid artery to examine the presence of vascular risk factors. Neuropsychological tests were combined to form six cognitive domains: Global cognition, language, visuospatial abilities, learning and memory, attention and executive functions. Multivariable analyses (using age, education, and ApoE ε4 expression as covariates) were conducted. Participants with increased IMT showed poorer performance in memory and those with carotid stenosis showed poorer performance in language, visuospatial abilities and attention, independent of age, education or ApoΕ Îµ4 expression. The results support the use of vascular markers in cognitive assessments of aged individuals.