Modulation of the silica sol-gel composition for the promotion of direct electron transfer to encapsulated cytochrome

The direct electron transfer between indium-tin oxide electrodes (ITO) and cytochrome c encapsulated in different sol-gel silica networks was studied. Cyt c@silica modified electrodes were synthesized by a two-step encapsulation method mixing a phosphate buffer solution with dissolved cytochrome c and a silica sol prepared by the alcohol-free sol-gel route. These modified electrodes were characterized by cyclic voltammetry, UV-vis spectroscopy, and in situ UV-vis spectroelectrochemistry. The electrochemical response of encapsulated protein is influenced by the terminal groups of the silica pores. Cyt c does not present electrochemical response in conventional silica (hydroxyl terminated) or phenyl terminated silica. Direct electron transfer to encapsulated cytochrome c and ITO electrodes only takes place when the protein is encapsulated in methyl modified silica networks.We gratefully acknowledge Jesus Yanez and Prof. Jose Miguel Martin-Martinez from the Laboratory of Adhesion and Adhesives (University of Alicante) for their assistance in the measurements of contact angle. We also acknowledge the Financial support from the Spanish Ministerio de Economia y Competitividad and FEDER y Ciencia (MAT2010-15273), Generalitat Valenciana (PROMETEO2013/038), and the Fundacion Ramon Areces (CIVP16A1821). Alonso Gamero-Quijano is grateful to Generalitat Valenciana (Santiago Grisolia Program) for the funding of his research fellowship.Gamero-Quijano, A.; Huerta, F.; Morallón, E.; Montilla, F. (2014). Modulation of the silica sol-gel composition for the promotion of direct electron transfer to encapsulated cytochrome. Langmuir. 30(34):10531-10538. https://doi.org/10.1021/la5023517S1053110538303

A case-control and cohort study to determine the relationship between ethnic background and severe COVID-19.

BACKGROUND: People of minority ethnic backgrounds may be disproportionately affected by severe COVID-19. Whether this relates to increased infection risk, more severe disease progression, or worse in-hospital survival is unknown. The contribution of comorbidities or socioeconomic deprivation to ethnic patterning of outcomes is also unclear. METHODS: We conducted a case-control and a cohort study in an inner city primary and secondary care setting to examine whether ethnic background affects the risk of hospital admission with severe COVID-19 and/or in-hospital mortality. Inner city adult residents admitted to hospital with confirmed COVID-19 (n = 872 cases) were compared with 3,488 matched controls randomly sampled from a primary healthcare database comprising 344,083 people residing in the same region. For the cohort study, we studied 1827 adults consecutively admitted with COVID-19. The primary exposure variable was self-defined ethnicity. Analyses were adjusted for socio-demographic and clinical variables. FINDINGS: The 872 cases comprised 48.1% Black, 33.7% White, 12.6% Mixed/Other and 5.6% Asian patients. In conditional logistic regression analyses, Black and Mixed/Other ethnicity were associated with higher admission risk than white (OR 3.12 [95% CI 2.63–3.71] and 2.97 [2.30–3.85] respectively). Adjustment for comorbidities and deprivation modestly attenuated the association (OR 2.24 [1.83–2.74] for Black, 2.70 [2.03–3.59] for Mixed/Other). Asian ethnicity was not associated with higher admission risk (adjusted OR 1.01 [0.70–1.46]). In the cohort study of 1827 patients, 455 (28.9%) died over a median (IQR) of 8 (4–16) days. Age and male sex, but not Black (adjusted HR 1.06 [0.82–1.37]) or Mixed/Other ethnicity (adjusted HR 0.72 [0.47–1.10]), were associated with in-hospital mortality. Asian ethnicity was associated with higher in-hospital mortality but with a large confidence interval (adjusted HR 1.71 [1.15–2.56]). INTERPRETATION: Black and Mixed ethnicity are independently associated with greater admission risk with COVID-19 and may be risk factors for development of severe disease, but do not affect in-hospital mortality risk. Comorbidities and socioeconomic factors only partly account for this and additional ethnicity-related factors may play a large role. The impact of COVID-19 may be different in Asians. FUNDING: British Heart Foundation; the National Institute for Health Research; Health Data Research UK

Oxytocin Modulates Amygdala Reactivity to Masked Fearful Eyes

The amygdala reveals enhanced reactivity to fearful eye whites, even when they are backwardly masked by a neutral face and therefore processed with limited visual awareness. In our fMRI study, we investigated whether this effect is indeed associated with fear detection within the eyes of the neutral face mask, or more generally, with reactivity to any salient increase in eye white area. In addition, we examined whether a single dose of intranasal oxytocin would modulate amygdala responses to masked fearful eye whites via a double-blind, placebo-controlled pharmacological protocol. We found that increased amygdala responses to salient changes within a face’s eye region occurred specifically for masked fearful eyes but not for similar increases in white area as induced by nonsocial control stimuli. Administration of oxytocin attenuated amygdala responses to masked fearful eye whites. Our results suggest that the amygdala is particularly tuned to potential threat signals from the eye region. The dampening effects of oxytocin on early amygdala reactivity may reflect reduced vigilance for facial threat cues at a preconscious level. Future studies may investigate whether this early modulation accounts for the beneficial effects of oxytocin on social cognition in anxiety-related disorders, as suggested by previous studies