Predictors of damage accrual and its impact on health-related quality of life of thrombotic antiphospholipid syndrome: Independent validation of the damage index for antiphospholipid syndrome (DIAPS).

OBJECTIVES: We aim to independently assess the validity of the damage index for antiphospholipid syndrome (DIAPS) in thrombotic antiphospholipid syndrome (APS) patients by exploring the prevalence and risk factors of organ damage and evaluating its impact on health-related quality of life (HR-QoL). METHODS: Cross-sectional study including all thrombotic APS patients (Sydney criteria) attending a Portuguese tertiary centre. Damage was assessed using the DIAPS, and HR-QoL using the 3- and 5-level EuroQol HR-QoL (EQ-D5-3L and 5L), and Visual Analogue Scale (VAS) applied via a phone questionnaire. Spearman's correlation between DIAPS and the HR-QoL scales was performed. Risk factors for damage accrual and HR-QoL impairment were explored using univariate and multivariate logistic regression. RESULTS: Among the 108 patients (female, 65.7%; white, 90.7%; primary APS, 75.9%; median disease duration, 6 years), damage (DIAPS≥1) developed in 48.2% of patients (mean ± SD DIAPS, 3.08 ± 1.83). DIAPS's neuropsychiatric domain was the most affected (24.2%), followed by the peripheral vascular domain (20.3%). No clinical, demographic nor laboratory parameters were significantly associated with damage. Regarding HR-QoL, pain/discomfort, anxiety/depression and usual activities domains were the most frequently impaired in both scales. DIAPS's domains correlated similarly with the EQ-5D-3L and 5L scales' individual domains. Female sex, medical disorders, secondary APS and type of presenting thrombosis (arterial) increased the risk of HR-QoL impairment. Total DIAPS was associated with higher odds of mobility, self-care and pain/discomfort impairment in both EQ-5D-3L and 5L scales but lost its independent risk in multivariable analysis. CONCLUSION: This external validation of DIAPS reinforces the ability of the score to correlate with HR-QoL while also highlighting risk factors for HR-QoL impairment other than damage accrual.

Brain damage serum biomarkers induced by COVID-19 in patients from northeast Brazil.

Neurological symptoms have been often reported in COVID-19 disease. In the present study, we evaluated brain damage associated with the increase of serum levels of neurological biomarkers S100B and neuron-specific enolase (NSE) induced by SARS-CoV-2 infection, in a population from Northeastern Brazil. Thirty-six healthy control (G1) individuals and 141 patients with confirmed COVID-19 were enrolled in this study. Positive-COVID-19 patients were divided into two groups according to the severity of illness by the National Institute of Health (NIH) criteria, 76 patients with mild symptoms for COVID-19 and (G2) and 65 with acute respiratory conditions requiring supplemental oxygenation via intensive care unit (ICU) admission (G3). A follow-up study was conducted with 23 patients from G2 14 (D14) and 21 (D21) days after the onset of symptoms. Serum levels of NSE and S100B were measured using the enzyme-linked immunoassay method (ELISA). Results revealed a significant positive association between G3 patients and S100B serum expression (p = 0.0403). The serum levels of NSE were also significantly enhanced in the G3 group compared to the control (p < 0.0001) and G2 group (p < 0.0001). In addition, clinical features such as symptoms and oxygenation status were not correlated with NSE or S100B serum expression. The follow-up study demonstrated a decrease over time (21 days) in NSE serum expression (p < 0.0001). These results suggest that brain damage is followed by acute virus exposure, with no long-term effects. Future work examining COVID-19 recovery will shed light on chronic neurological damage of SARS-CoV-2 infection.

Evaluating internalization and recycling of folate receptors in breast cancer cells using quantum dots.

Folic acid (FA) regulates metabolic activities essential to the human body. FA receptor (FR) overexpression has been reported for many cancers, but there are still few or conflicting data about FRs in breast cancer cells. Quantum dots (QDs) have arisen as tools to elucidate aspects on FRs, due to their unique physicochemical properties. Herein, QDs conjugated to FA were explored to study the internalization and recycling of FRs in breast cancer cells, using HeLa as an out-group control. QDs were covalently conjugated to FA under different conditions. The best conjugate was applied to study FRs in HeLa, MCF7, MDA-MB231, and T47D cells applying confocal microscopy and flow cytometry analyses. The conjugation efficiency and specificity were evaluated, respectively, using fluorescence correlation spectroscopy (FCS) and saturation assays. FCS confirmed the effectiveness of the conjugation. HeLa and T47D had/internalized a higher amount of FRs (95% and 90% of labeling, respectively) than MDA-MB231 cells (68%). MCF7 cells seem to have very low functional FRs (3%). Saturation assays proved the specificity of QD-FA conjugates and suggested that FR recycling rate is low in the majority of cells studied, except for T47D. QD-FA conjugates were successfully developed. Therapies targeting FRs may be more effective for HeLa, T47D, and MDA-MB231.

Quantum dots functionalized with 3-mercaptophenylboronic acids as novel nanoplatforms to evaluate sialic acid content on cell membranes.

Sialic acids (SAs) modulate essential physiological and pathological conditions, including cell-cell communication, immune response, neurological disorders, and cancer. Besides, SAs confer negative charges to cell membranes, also contributing to hemorheology. Phenylboronic acids, called as mimetic lectins, have been highlighted to study SA profiles. The association of these interesting molecules with the optical properties of quantum dots (QDs) can provide a deeper/complementary understanding of mechanisms involving SAs. Herein, we explored the thiol affinity to the QD surface to develop a simple, fast and direct attachment procedure to functionalize these nanocrystals with 3-mercaptophenylboronic acids (MPBAs). The functionalization was confirmed by fluorescence correlation spectroscopy and inductively coupled plasma spectrometry. The conjugate specificity/efficiency was proved in experiments using red blood cells (RBCs). A labeling >90% was found for RBCs incubated with conjugates, which reduced to 17% after neuraminidase pretreatment. Moreover, QDs-MPBA conjugates were applied in a comparative study using acute (KG-1) and chronic (K562) myelogenous leukemia cell lines. Results indicated that KG-1 membranes have a greater level of SA, with 100% of cells labeled and a median of fluorescence intensity of ca. 2.5-fold higher when compared to K562 (94%). Therefore, this novel QDs-MPBA conjugate can be considered a promising nanoplatform to evaluate SA contents in a variety of biological systems.