Tumor hypoxia is one of the major challenges for the treatment of tumors, as it may negatively affect the efficacy of various anticancer modalities. In this study, a tumor-targeted redox-responsive composite biocatalyst is designed and fabricated, which may combine tumor starvation therapy and low-temperature photothermal therapy for the treatment of oxygen-deprived tumors. The nanosystem was prepared by loading porous hollow Prussian Blue nanoparticles (PHPBNs) with glucose oxidase (GOx) and then coating their surface with hyaluronic acid (HA) via redox-cleavable linkage, therefore allowing the nanocarrier to bind specifically with CD44-overexpressing tumor cells while also exerting control over the cargo release profile. The nanocarriers are designed to enhance the efficacy of the hypoxia-suppressed GOx-mediated starvation therapy by catalyzing the decomposition of intratumoral hydroperoxide into oxygen with PHPBNs, and the enhanced glucose depletion by the two complementary biocatalysts may consequently suppress the expression of heat shock proteins (HSPs) after photothermal treatment to reduce their resistance to the PHPBN-mediated low-temperature photothermal therapies.

Background: Medical students experience depression and anxiety at a higher rate than the general population or students from other specialties. While there is a growing literature on the high prevalence of depression and anxiety symptoms and about potential risk factors to the prevalence of depression and anxiety symptoms among medical students, there is a paucity of evidence focused on the prevalence of depression and anxiety symptoms and associations with family function, social support and coping styles in Chinese vocational medicine students. This study aims to investigate the prevalence of depression and anxiety symptoms among Chinese medical students and assess the correlation between depression/anxiety symptoms and family function, social support and coping styles. Methods: A sample of 2057 medical students from Chongqing Medical and Pharmaceutical College in China was investigated with a self-report questionnaire, which included demographic information, Zung self-rating depression scale, Zung Self-Rating Anxiety Scale, Family APGAR Index, Social Support Rating Scale and Trait Coping Style Questionnaire. Results: The prevalence of depression and anxiety symptoms among the medical students was 57.5 and 30.8%, respectively. Older students(≥20 years) experienced higher levels of depression and anxiety. More depression and anxiety symptoms were exhibited among students with big financial burden, big study-induced stress and poor sleep quality. Students with large employment pressure showed more anxiety symptoms. Students who live alone or had bad relationship with their lovers or classmates or friends showed higher depression and anxiety scores. Depression and anxiety symptoms had highly significant correlations with family functioning, social support and coping style. Conclusions: Academic staffs should take measures to reduce depression and anxiety among medical students and to provide educational counseling and psychological support for students to cope with these problems.

To investigate the influence of surface-functionalized substrates with nanostructures on the behaviors of mesenchymal stem cells, we conjugated bone morphogenetic protein 2 (BMP2) onto TiO(2) nanotubes with different diameter sizes of 30, 60, and 100 nm for in vitro study. Polydopamine was employed as the intermediate layer for the conjugation of BMP2. The successful conjugation of BMP2 onto TiO(2) nanotubes was revealed by field-emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), and contact angle measurements. Immunofluorescence staining of vinculin, osteocalcin (OCN), and osteopontin (OPN) revealed that BMP2-functionalized TiO(2) nanotubes was favorable for cell growth. More importantly, MSCs cultured onto BMP2-functionalized TiO(2) nanotubes displayed significantly higher (p < 0.05 or p < 0.01) differentiation levels of ALP and mineralization after 7 and 14 day cultures, respectively. The results suggested that surface functionalization of TiO(2) nanotubes with BMP2 was beneficial for cell proliferation and differentiation. The approach presented here has potential application for the development of titanium-based implants for enhanced bone osseointegration.

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The size‐mediated cytotoxicity of TiO2 nanoparticles is investigated at the cellular and molecular levels. The cytotoxicity dramatically increases around a particle size of 100 nm (nanoscale effect). This finding affords new insights into the cytotoxicity of nanomaterials, and has potential implications in the design of nanostructured biomaterials.