All-experimental analysis of doubly resonant sum-frequency generation spectra: Application to aggregated rhodamine films.

A new method is proposed to analyze Doubly Resonant infrared-visible Sum-Frequency Generation (DR-SFG) spectra. Based on the transform technique, this approach is free from assumptions about vibronic modes, energies, or line widths and accurately captures through the overlap spectral function all required aspects of the vibronic structure from simple experimental linear absorption spectra. Details and implementation of the method are provided along with three examples treating rhodamine thin films about one monolayer thick. The technique leads to a perfect agreement between experiment and simulations of the visible DR-SFG line shapes, even in the case of complex intermolecular interactions resulting from J-aggregated chromophores in heterogeneous films. For films with mixed H- and J-aggregates, separation of their responses shows that the J-aggregate DR-SFG response is dominant. Our analysis also accounts for the unexplained results published in the early times of DR-SFG experiments.

Interrogating COVID-19 vaccine intent in the Philippines with a nationwide open-access online survey.

To mitigate the unprecedented health, social, and economic damage of COVID-19, the Philippines is undertaking a nationwide vaccination program to mitigate the effects of the global pandemic. In this study, we interrogated COVID-19 vaccine intent in the country by deploying a nationwide open-access online survey, two months before the rollout of the national vaccination program. The Health Belief Model (HBM) posits that people are likely to adopt disease prevention behaviors and to accept medical interventions like vaccines if there is sufficient motivation and cues to action. A majority of our 7,193 respondents (62.5%) indicated that they were willing to be vaccinated against COVID-19. Moreover, multivariable analysis revealed that HBM constructs were associated with vaccination intention in the Philippines. Perceptions of high susceptibility, high severity, and significant benefits were all good predictors for vaccination intent. We also found that external cues to action were important. Large majorities of our respondents would only receive the COVID-19 vaccines after many others had received it (72.8%) or after politicians had received it (68.2%). Finally, our study revealed that most (21%) were willing to pay an amount of PHP 1,000 (USD20) for the COVID-19 vaccines with an average willing-to-pay amount of PHP1,892 (USD38).

Effect of selenium supplementation on biochemical markers and outcome in critically ill patients.

BACKGROUND & AIMS: This study aimed to assess the effect of high dose selenium (Se) supplementation on Se status in blood, oxidative stress, thyroid function and possible effects on requirement for renal replacement therapy (RRT) in severely septic patients admitted to the intensive care unit (ICU). METHODS: This prospective single-centre study was carried out in 40 septic ICU patients who were randomized to high dose Se (Se+ group, N=18 (474, 316, 158 microg/day), each for 3 consecutive days followed by a standard dose of 31.6 microg/day of Se given as sodium selenite whereas the control group (Se-, N=22) received only the standard dose of Se. Plasma Se, glutathione peroxidase (GSH-Px), F2 isoprostanes, thyroid function tests (total T4 and total T3), C-reactive protein (CRP) and red blood cell (RBC) GSH-Px were estimated on day 0, 3, 7, 14. RESULTS: In the Se+ group, plasma Se increased by day 3 and 7 (P<0.0001) and day 14 (P=0.02), plasma GSH-Px increased by day 3 and 7 (P=0.01) as compared to Se- group. There was a significant negative correlation between plasma Se and SOFA (sepsis related organ failure assessment) (r=-0.36, P=0.03) along with low plasma Se and high CRP at the time of admission. Requirement for renal replacement therapy was not significantly different between the groups. CONCLUSION: Although high dose Se supplementation increased plasma Se and GSH-Px activity, it did not reduce oxidative damage or the requirement for RRT. Se levels in blood are influenced by redistribution and severity of illness and therefore should be interpreted with caution.

Periostin secreted by glioblastoma stem cells recruits M2 tumour-associated macrophages and promotes malignant growth.

Tumour-associated macrophages (TAMs) are enriched in glioblastoma multiformes (GBMs) that contain glioma stem cells (GSCs) at the apex of their cellular hierarchy. The correlation between TAM density and glioma grade suggests a supportive role for TAMs in tumour progression. Here we interrogated the molecular link between GSCs and TAM recruitment in GBMs and demonstrated that GSCs secrete periostin (POSTN) to recruit TAMs. TAM density correlates with POSTN levels in human GBMs. Silencing POSTN in GSCs markedly reduced TAM density, inhibited tumour growth, and increased survival of mice bearing GSC-derived xenografts. We found that TAMs in GBMs are not brain-resident microglia, but mainly monocyte-derived macrophages from peripheral blood. Disrupting POSTN specifically attenuated the tumour-supportive M2 type of TAMs in xenografts. POSTN recruits TAMs through the integrin αvß3 as blocking this signalling by an RGD peptide inhibited TAM recruitment. Our findings highlight the possibility of improving GBM treatment by targeting POSTN-mediated TAM recruitment.