No abstract

Since December 2019, the novel COVID-19 outbreak has spread rapidly around the globe and infected millions of people. Although the major transmission route of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is considered to be airborne droplets and close contact, the ocular transmission route has been reported with great concern. The current work summarises the characteristics of SARS-CoV-2, the ocular distribution of the major SARS-CoV-2 binding protein, and the experimental and clinical evidence of the ocular transmission route. Although it seems that the likelihood of the ocular surface being an infection gateway is low, SARS-CoV-2 infection or transmission via the ocular surface may cause conjunctivitis and other ocular discomfort. Therefore, good eye protection is an essential safeguard procedure, especially for medical staff.

We report the atomic N-doped SnO2 films with p-type conduction grown via reactive sputtering at high nitrogen partial pressure. From the high-resolution x-ray photoelectron spectroscopy (XPS) and x-ray diffraction patterns, it is deduced that the N 1s with binding energy of 397 eV could be attributed to the atomic N in the SnO2 films. In addition, the results of Hall effect measurement indicate that the atomic N incorporated substitutionally at O sites act as acceptors, which is responsible for the p-type conduction of the N-doped SnO2 films. It is believed that these findings should stimulate further research on p-type SnO2 films and SnO2-based ultraviolet optoelectronic devices.

Tyrosine hydroxylase (TH), the initial enzyme in the melanin pathway, catalyzes tyrosine conversion into Dopa. Although expression and regulation of TH have been shown to affect cuticle pigmentation in insects, no direct functional studies to date have focused on the specific physiological processes involving the enzyme during mosquito development. In the current study, silencing of AsTH during the time period of continuous high expression in Anopheles sinensis pupae led to significant impairment of cuticle tanning and thickness, imposing a severe obstacle to eclosion in adults. Meanwhile, deficiency of melanin in interference individuals led to suppression of melanization, compared to control individuals. Consequently, the ability to defend exogenous microorganisms declined sharply. Accompanying down-regulation of the basal expression of five antimicrobial peptide genes resulted in further significant weakening of immunity. TH homologs as well as the composition of upstream transcription factor binding sites at the pupal stage are highly conserved in the Anopheles genus, implying that the TH-mediated functions are crucial in Anopheles. The collective evidence strongly suggests that TH is essential for Anopheles pupae tanning and immunity and provides a reference for further studies to validate the utility of the key genes involved in the melanization pathway in controlling mosquito development.

Herein, a novel phototheranostic nanocomplex that is self-assembled from bovine serum albumin (BSA) and indocyanine green (ICG) is developed for enhanced near-infrared (NIR) fluorescence imaging, which benefits the guidance on in vivo cancer photothermal therapy (PTT). The study confirms that the binding of ICG with the bind sits on the albumin will result in improved hydrolytic stability and high photoluminescence quantum yield (PLQY). The ICG loading ratio in the nanocomplex is optimized and confirms the loading ratio of 0.5% ICG to be the optimal content. The optimized ICG-BSA nanocomplex (ICG-BSA NC) possesses a higher PLQY of 16.8% than that of free ICG (2.7%). The high PLQY and efficient passive targeting ability of ICG-BSA NC help improve its in vivo tumor accumulation and NIR fluorescence imaging significantly. Under laser irradiation, efficient PTT with obvious tumor growth suppression on a triple negative breast tumor model can be observed in the ICG-BSA NC treated group.