A highly integrated digital PCR system with on-chip heating for accurate DNA quantitative analysis.

Digital polymerase chain reaction (dPCR) is extensively used for highly sensitive disease diagnosis due to its single-molecule detection ability. However, current dPCR systems require intricate DNA sample distribution, rely on cumbersome external heaters, and exhibit sluggish thermal cycling, hampering efficiency and speed of the dPCR process. Herein, we presented the development of a microwell array based dPCR system featuring an integrated self-heating dPCR chip. By utilizing hydrodynamic and electrothermal simulations, the chip's structure is optimized, resulting in improved partitioning within microwells and uniform thermal distribution. Through strategic hydrophilic/hydrophobic modifications on the chip's surface, we effectively secured the compartmentalization of sample within the microwells by employing an overlaying oil phase, which renders homogeneity and independence of samples in the microwells. To achieve precise, stable, uniform, and rapid self-heating of the chip, the ITO heating layer and the temperature control algorithm are deliberately designed. With a capacity of 22,500 microwells that can be easily expanded, the system successfully quantified EGFR plasmid solutions, exhibiting a dynamic linear range of 105 and a detection limit of 10 copies per reaction. To further validate its performance, we employed the dPCR platform for quantitative detection of BCR-ABL1 mutation gene fragments, where its performance was compared against the QuantStudio 3D, and the self-heating dPCR system demonstrated similar analytical accuracy to the commercial dPCR system. Notably, the individual chip is produced on a semiconductor manufacturing line, benefiting from mass production capabilities, so the chips are cost-effective and conducive to widespread adoption and accessibility.

Oral administration of camellia oil ameliorates obesity and modifies the gut microbiota composition in mice fed a high-fat diet.

Obesity, which is often caused by adipocyte metabolism dysfunction, is rapidly becoming a serious global health issue. Studies in the literature have shown that camellia oil (Camellia oleifera Abel) exerted potential lipid regulation and other multiple biological activities. Here, we aimed to investigate the effects of camellia oil on obese mice induced by a high-fat diet and to explore gut microbiota alterations after camellia oil intervention. The results showed that oral administration of camellia oil dramatically attenuated the fat deposits, serum levels of the total cholesterol, triacylglycerol, low-density lipoprotein cholesterol, fasting plasma glucose, the atherosclerosis index, the hepatic steatosis and inflammation in high-fat diet-induced obese mice. Meanwhile, the high-density lipoprotein cholesterol level in obese mice was enhanced after the camellia oil treatment. Furthermore, 16S rRNA analysis showed that certain aspects of the gut microbiota, especially the gut microbiota diversity and the relative abundance of Actinobacteria, Coriobacteriaceae, Lactobacillus and Anoxybacillus, were significantly increased by camellia oil treatment while the ratio of Firmicutes to Bacteroidetes was decreased. Taken together, our finding suggested that camellia oil was a potential dietary supplement and functional food for ameliorating fat deposits, hyperglycemia and fatty liver, probably by modifying the gut microbiota composition.