Construction of a Three-Dimensional-Printed Immunosensing Platform Based on Smartphone Photothermal Signal Integration.

The combination of the photothermal effect and immunoassay serves as a potent tool for crafting cost-effective and user-friendly biosensing systems. To ensure efficient light-to-heat conversion, we integrated three-dimensional-printed (3D printed) technology to devise a novel design. This design functions as the structural support for both the cell phone and laser probe, as well as a means for sample handling. The main body features a three-way cavity structure, securing the test sample at a fixed position to maintain consistent light distance and angle, thereby minimizing testing errors. Card slot insert facilitates precise sample positioning to ensure the adequacy of receiving light. The sample holder's wide front and narrow back design enables the accommodation of fixed samples while providing a broad field of view, with intervals therein effectively preventing cascading heat. Our design employs MB@MOF235 (methylene blue adsorbed by iron terephthalate) as the photothermal reagent, successfully enabling the detection of α-fetoprotein (AFP). The detection range spans from 0.01 to 50 ng/mL, with a lower detection limit (LOD) of 0.032 pg/mL. The detection method, combining simplicity, portability, and visualization, offers a reliable reference for furthering precision medicine toward personalized medicine. Meanwhile, to verify the method's accuracy electrochemical testing was conducted to support the proof using the electro-oxidizing activity of MB.

Quenching study of Cu2S-MPA/NGODs composites in electrochemiluminescence detection by modulating resonance energy transfer and adsorption process.

This study explores the principles of resonance energy transfer and adsorption modulation using composites of Cu2S-MPA/NGODs. These composites can efficiently control the quenching process of electrochemiluminescence (ECL). Mercaptopropionic acid (MPA) was added during the synthesis of Cu2S-MPA to enhance its attachment to nitrogen-doped graphene quantum dots (NGODs). The UV absorption peaks of NGODs coincided with the emission peaks of luminol ECL, enabling resonance energy transfer and enhancing the quenching capability of Cu2S-MPA. Meanwhile, there is another quenching strategy. When the readily reducible Cu+ ions underwent partial reduction to Cu when they were bound to NGODs. This weakened the electrocatalytic effect on reactive oxygen species (ROS) and had a detrimental impact on electron transfer. Under optimal conditions, the immunosensor ECL intensity decreased linearly with the logarithm of carcinoembryonic antigen (CEA) concentration in the range of 0.00001-40 ng/mL, with a detection limit of 0.269 fg/mL. The sensor was effectively utilized for the identification of CEA in actual serum samples.

A comparison study of the influence of milk protein versus whey protein in high-protein diets on adiposity in rats.

High-protein diets are known to reduce weight and fat deposition. However, there have been only a few studies on the efficacy of different types of high-protein diets in preventing obesity. Therefore, the emphasis of this study lies in comparing the efficacy of two high-protein diets (milk protein and whey protein) in preventing obesity and exploring specific mechanisms. Eighty Sprague Dawley rats were divided into two groups and fed with milk protein concentrate (MPC) and whey protein concentrate (WPC) for 12 weeks. Each group was divided into four levels: two low-fat regimens with either low or high protein content (L-14%, L-40%) and two high-fat regimens with either low or high protein content (H-14%, H-40%). The studies we have performed showed that rats treated with MPC at the 40% protein level had significantly reduced body weight, fat weight and fat ratio gain induced by a high-fat diet, while the protein level in the WPC group had no effect on body weight or body fat in rats fed with a high-fat diet. What is more, rats fed with MPC at the H-40% energy level showed a significant decrease in plasma triglyceride, total cholesterol and low-density lipoprotein cholesterol levels and a significant increase in plasma high-density lipoprotein cholesterol levels compared with the H-14% energy level group. In contrast, in the WPC groups, increasing the protein content in high-fat diets had no significant influence on plasma lipid levels. The results of the amino acid composition of the two proteins and plasma showed that the MPC diet of 40% protein level increased the transsulfuration pathway in rats, thereby increasing the level of H2S. This research work has shown that not all types of high-protein diets can effectively prevent obesity induced by high-fat diets, as effectiveness depends on the amino acid composition of the protein.

Dietary Dityrosine Induces Mitochondrial Dysfunction by Diminished Thyroid Hormone Function in Mouse Myocardia.

Oxidized tyrosine products (OTP) have been detected in commercial foods with high protein content, such as meat and milk products. OTP intake induces tissue oxidative stress and affects the normal activity of the hypothalamic-pituitary-thyroid axis (HPT). This study aims to investigate the effects of OTP and their main product, dityrosine (Dityr), on mouse myocardial function and myocardial energy metabolism. Mice received daily intragastric administration of either tyrosine (Tyr; 420 µg/kg body weight), Dityr (420 µg/kg body weight), or OTP (1909 µg/kg body weight) for 35 days. Additionally, H9c2 cells were incubated with various concentrations of Dityr for 72 h. We found that OTP and pure Dityr induced oxidative stress in growing mice and in H9c2 cells, resulting in a redox state imbalance, myocardial injury, mitochondrial dysfunction, and energy metabolism disorder. Dityr interferes with T3 regulation of the myocardium via the PI3K/AKT/GSK3ß pathway, leading to myocardial mitochondrial damage and energy metabolism disorders. Food-borne OTP, especially Dityr, can disrupt thyroid hormone function in mouse myocardia leading to mitochondrial dysfunction, energy metabolism disorder, and oxidative stress.