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In 2018, to help undergraduate medical students strengthen their self-learning and scientific research skills, we introduced an instructional model that combined literature-based learning with experimental design. We tested this model on the molecular biology class at Tongji University. In the first step of the model, a topic is chosen, and students find, read, and evaluate scientific papers in groups and deliver presentations. In the second step, they design scientific experiments in groups and discuss their proposed experiments in class, which is to be followed by further experimental verification in the lab course. This entire activity was given 20% weightage in the final score. The model led to better student-centered teaching and self-directed learning according to quantitative and qualitative assessment. Students showed great interest in literature and research. They enjoyed group work and gained experience in organization and presentation. Apart from a significant increase in final score, assessment data from students indicated that they were satisfied with this teaching model and considered it a positive experience. Looking at the positive impact of the literature-based learning and experiment design model, we support its continued use for teaching molecular biology to undergraduate medical students.

Background: Ferroptosis is extremely relevant to the progression of neurodegenerative pathologies such as Alzheimer's disease (AD). Ubiquitin-specific proteases (USP) can affect the NADPH oxidase family. Objective: Our study aimed to elucidate the potential role and molecular basis of a certain USP19 in reducing ferroptosis and mitochondrial injury in AD cells by targeting NOX4 stability. Methods: The deubiquitinase USP family gene USP19, which affects the stability of NOX4 protein, was first screened. The cell model of AD was constructed after interfering with SH-SY5Y cells by Aβ1-40, and then SH-SY5Y cells were infected with lentiviral vectors to knock down USP19 and overexpress NOX4, respectively. Finally, the groups were tested for cell viability, changes in cellular mitochondrial membrane potential, lipid reactive oxygen species, intracellular iron metabolism, and NOX4, Mf1, Mf2, and Drp1 protein expression. Results: 5 μmol/L Aβ1-40 intervened in SH-SY5Y cells for 24 h to construct a cell model of AD. Knockdown of USP19 decreased the expression of NOX4 protein, promoted the expression of mitochondrial fusion proteins Mnf1 and Mnf2, and inhibited the expression of the splitting protein Drp1. Furthermore, USP19 knockdown decreased mitochondrial membrane potential, SOD, MDA, intracellular iron content and increased GSH/GSSG ratio in SH-SY5Y cells. Our study revealed that NOX4 protein interacts with USP19 and knockdown of USP19 enhanced ubiquitination to maintain NOX4 protein stability. Conclusions: USP19 attenuates mitochondrial damage in SH-SY5Y cells by targeting NOX4 protein with Aβ1-40. [ABSTRACT FROM AUTHOR]

Real‐time monitoring the therapeutic process of sonodynamic therapy (SDT) is essential to optimize the treatment course in time and eventually improve the efficacy. The generation of singlet oxygen (1O2) is a quintessential characteristic of SDT, which permits non‐invasive monitoring of SDT by real‐time imaging of 1O2 inside the tumor. Nonetheless, the majority of probes are unable to measure 1O2 in real time because of its short half‐life and strong oxidative capacity. Here, the study constructs a ratiometric nanoplatform (DTPI) utilizing two fluorescent probes and the sonosensitizer TiO2. The poisonous 1O2 generated by DTPI following ultrasonic (US) radiation efficiently destroys tumor cells. The structural disruption of fluorescent dye IR‐1061 by 1O2 leads to a reduction in the DTPI fluorescence signal at 1100 nm, while US radiation has no impact on the fluorescence signal at 1550 nm. Thus, DTPI provides a precise and consistent reflection of the treatment efficacy at the tumor site, leveraging the ratiometric fluorescence signal and variations in oxygen content throughout the treatment process. This ratiometric‐fluorescence‐based reflection strategy establishes an effective and dependable platform for the real‐time monitoring and assessment of the cancer therapeutic effect through ratiometric probes. [ABSTRACT FROM AUTHOR]

High hydrogen sulfide (H2S) expression has been shown to play a crucial role in tumor growth and proliferation in colon cancer. So far, most probes used for monitoring H2S offer single‐modal imaging, which makes the collection of accurate information for tumor diagnosis difficult. In the present study, a novel dual‐modal imaging probe in the second near‐infrared (NIR‐II, 950‐1700) window is proposed and constructed by coating a uniform shell of polydopamine (PDA) on the surface of cuprous oxide (Cu2O)‐conjugated downconversion nanoparticles (DCNPs). Of note, DCNP‐Cu2O@PDA is in the "on" state, with emission centered at 1550 nm (irradiation using a 980nm laser) in non‐neoplastic tissues. Colon tumors with endogenous H2S overexpression can induce the in situ transformation of Cu2O to copper sulfide (Cu2‐XS）. Owing to the competitive absorption between Cu2‐XS and DCNPs at a wavelength of 980 nm, the generated DCNP‐Cu2‐XS@PDA exhibits a quenched NIR‐II fluorescence (FL) signal. Meanwhile, Cu2‐XS exhibits a strong absorbance at 1250 nm, enhancing the NIR‐II photoacoustic (PA) signal accompanied by NIR‐II FL attenuation. The switching in PA and FL signals at the tumor site offered "double assurances" for the accurate monitoring of H2S. [ABSTRACT FROM AUTHOR]

H2O2 is a widely used eco‐friendly oxidant and a potential energy carrier. Photocatalytic H2O2 production from water and O2 is an ideal approach with the potential to address the current energy crisis and environmental issues. Three zig‐zag two‐dimensional coordination polymers (2D CPs), named CuX‐dptz, were synthesized by a rapid and facile method at room temperature, showing preeminent H2O2 photoproduction performance under pure water and open air without any additives. CuBr‐dptz exhibits a H2O2 production rate high up to 1874 μmol g−1 h−1, exceeding most reported photocatalysts under this condition, even comparable to those supported by sacrificial agents and O2. The coordination environment of Cu can be modulated by halogen atoms (X=Cl, Br, I), which in turn affects the electron transfer process and finally determines the reaction activity. This is the first time that 2D CPs have been used for photocatalytic H2O2 production in such challenging conditions, which provides a new pathway for the development of portable in situ H2O2 photosynthesis devices. [ABSTRACT FROM AUTHOR]

Biochemistry and cellular biology courses for medical students at Tongji University include the assessment that provides students with feedback to enhance their learning, which is a type of formative assessment. However, frequent instant feedback and guidance for students is often absent or inconsistently included in the teaching process. WeChat, the most popular Chinese social media, was introduced in biochemistry and cellular biology course. A WeChat official account (OA) was set up as an instant interactive platform. Over a period of two semesters, OA sent 73 push notifications. The components included course notices, preclass thought questions, after-class study materials, answer questions and feedback, simulation exercises, teacher-student interaction, and research progress relevant to the course. WeChat OA served as an active-learning teaching tool, provided more frequent feedback and guidance to students, and facilitated better student-centered communication in the teaching process. Using the WeChat OA in medical teaching emphasized interactive, interoperable, effective, engaging, adaptable, and more participatory teaching styles. As a new platform, WeChat OA was free, Internet-reliant, and easily managed. Using this new medium as a communication tool accelerated further advancement of instant feedback and improvement in teaching activities. Notifications and interactive feedback via the mobile social medium WeChat OA anytime and anywhere facilitated a student-centered teaching mode. Use of WeChat OA significantly increased the proportion of students interactively participating and resulted in a high degree of student satisfaction.