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Abstract In addition to an inflammatory reaction, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)-infected patients present lymphopenia, which we recently reported as being related to abnormal programmed cell death. As an efficient humoral response requires CD4 T-cell help, we hypothesized that the propensity of CD4 T cells to die may impact the quantity and quality of the humoral response in acutely infected individuals. In addition to specific immunoglobulins (Ig)A, IgM, and IgG against SARS-CoV-2 nucleocapsid (N), membrane (M), and spike (S1) proteins, we assessed the quality of IgG response by measuring the avidity index. Because the S protein represents the main target for neutralization and antibody-dependent cellular cytotoxicity responses, we also analyzed anti-S-specific IgG using S-transfected cells (S-Flow). Our results demonstrated that most COVID-19 patients have a predominant IgA anti-N humoral response during the early phase of infection. This specific humoral response preceded the anti-S1 in time and magnitude. The avidity index of anti-S1 IgG was low in acutely infected individuals compared to convalescent patients. We showed that the percentage of apoptotic CD4 T cells is inversely correlated with the levels of specific IgG antibodies. These lower levels were also correlated positively with plasma levels of CXCL10, a marker of disease severity, and soluble Fas ligand that contributes to T-cell death. Finally, we found lower S-Flow responses in patients with higher CD4 T-cell apoptosis. Altogether, these results demonstrate that individuals with high levels of CD4 T-cell apoptosis and CXCL10 have a poor ability to build an efficient anti-S response. Consequently, preventing CD4 T-cell death might be a strategy for improving humoral response during the acute phase, thereby reducing COVID-19 pathogenicity.

Alejandro Rodriguez-Garcia,1 Alejandro Babayan-Sosa,2 Arturo Ramirez-Miranda,3 Concepcion Santa Cruz-Valdes,3 Everardo Hernandez-Quintela,4 Julio C Hernandez-Camarena,1 Nallely Ramos-Betancourt,5 Regina Velasco-Ramos,2 Raul E Ruiz-Lozano1 1Tecnologico de Monterrey, School of Medicine and Health Sciences, Institute of Ophthalmology and Visual Sciences, Cornea and External Disease Service, Monterrey, Mexico; 2Cornea and Refractive Surgery Service, Fundación Hospital Nuestra Señora de la Luz, I. A. P, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico; 3Cornea and Refractive Surgery Service, Instituto de Oftalmología Conde de Valenciana, I.A.P, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico; 4Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA; 5Asociación para Evitar la Ceguera en México, I.A.P, Mexico City, MexicoCorrespondence: Alejandro Rodriguez-Garcia, Tecnologico de Monterrey, School of Medicine and Health Sciences, Institute of Ophthalmology and Visual Sciences, Cornea and External Disease Service, Hospital Zambrano Hellion, TecSalud, Av. Batallon de San Patricio #112, Col. Real de San Agustin, San Pedro Garza Garcia, N.L. CP. 66278, Mexico, Tel/Fax +52 81 88 88 05 51, Email immuneye@gmail.comAbstract: Dry eye disease (DED) has a higher prevalence than many important systemic disorders like cardiovascular disease and diabetes mellitus, representing a significant quality of life burden for the affected patients. It is a common reason for consultation in general eye clinics worldwide. Nowadays, the diagnostic and therapeutic approach at the high corneal and ocular surface specialty level should be reserved for cases of severe and chronic dry eye disease associated with systemic autoimmune diseases or complicated corneal and ocular surface pathologies. In such cases, the diagnostic and therapeutic approach is often complex, elaborate, time-consuming, and costly due to the use of extensive dry eye questionnaires, noninvasive electronic diagnostic equipment, and clinical laboratory and ancillary tests. However, other eye care specialists attend a fair amount of DED cases; therefore, its diagnosis, classification, and management should be simple, practical, achievable, and effective. Considering that many patients attending non-specialized dry eye clinics would benefit from better ophthalmological attention, we decided to elaborate a practical DED classification system based on disease severity to help clinicians discriminate cases needing referral to subspecialty clinics from those they could attend. Additionally, we propose a systematic management approach and general management considerations to improve patients’ therapeutic outcomes according to disease severity.Keywords: dry eye disease, fluorescein staining, tear breakup time, Schirmer test, tear osmolarity, dry eye questionnaire

La exposición crónica al arsénico (As) favorece el desarrollo de enfermedades como hidroarsenicismo o HACRE, hipertensión y cáncer, especialmente de piel, pulmón y vejiga. Asimismo, el flúor (F) produce fluorosis esquelética y dental. Desde 2006 la Organización Mundial de la Salud (OMS) recomienda una concentración máxima de As en agua potable de 0,01 mg/L; mientras en Argentina el valor continúa en estudio, aceptando 0,05 mg/L (si bien el Código Alimentario Argentino (CAA) indica 0,01 mg/L). La concentración máxima de F recomendada por la OMS es 1,5 mg/L; mientras CAA la regula según la temperatura media de la región. Este trabajo se localiza en caseríos dispersos en el monte a los alrededores de San José de Boquerón (Santiago del Estero). La zona carece de servicios básicos como energía eléctrica o agua potable. Sus pobladores consumen agua de pozo contaminada con As y F. Se busca proveer una solución, mediante el desarrollo e implementación de un filtro sustentable, con materiales económicos, que permita disminuir el contenido de As y F en agua para consumo. El filtro propuesto consiste en 4 baldes plásticos de 20 L, 1 Kg de clavos, arena, carbón de hueso-leña y granza. Tras el filtrado del agua contaminada con este sistema, se cuantificaron concentraciones de: As entre 0,025-0,05 mg/L y F entre 0,73-0,98 mg/L, conteniendo inicialmente 0,25 y 3,1 mg/L, respectivamente. Así, se lograron tratar 140 L (en 7 batches) de agua apta para consumo. Se evidenció la necesidad de acompañamiento durante la implementación del dispositivo en la zona.

Accountability policies through standardized testing are widespread in diverse educational systems. Based on an ethnographic research study, we sought to understand how a learning assessment policy, used for over three decades in primary and lower secondary education, is lived and interpreted in daily school life in Chile. This article analyzes how learning assessment policies are re-contextualized (translated and interpreted) in three elementary and high schools located in poor neighborhoods with different performance categorization according to students' test results. We conducted interviews and observations with teachers and school leadership team members. Results show that school actors experience the effects of testing both as a menace and as a pressure despite their different school categorization performance. They consider the tests a decontextualized and unjust measurement and therefore respond with similar strategies that seek to avoid these negative consequences. This study contributes to understanding the effects of tight accountability systems that attempt to place different levels of pressure through categorization.