An Optical System of Star Sensors with Accuracy Performance Varying with the Field of View.

The field of view and single-star measurement accuracy are crucial metrics for assessing the performance of a star sensor. The field of view determines the spatial range of stars that can be captured by the sensor, while the single-star measurement accuracy determines the precision of attitude determination and control for the star sensor. The optical system of conventional star sensors is constrained by imaging relationships. Once the detector is determined, improving either the field of view or the single-star measurement accuracy will result in the degradation of the other. To address this issue, we propose an optical system for star sensors with accuracy performance varying with the field of view. By controlling the relationship between the field focal length of the optical system and the field of view, it is possible to simultaneously enhance both the field of view and the single-star measurement accuracy. We have designed corresponding optical systems to address the requirements for improving the single-star measurement accuracy and field of view. The design results confirm the feasibility of this star sensor. The star sensors are capable of simultaneously meeting the requirements for star pattern recognition and attitude determination, presenting broad application prospects in fields such as space navigation.

Glutamate Dehydrogenase as a Promising Target for Hyperinsulinism Hyperammonemia Syndrome Therapy.

Hyperinsulinism-hyperammonemia syndrome (HHS) is a rare disease characterized by recurrent hypoglycemia and persistent elevation of plasma ammonia, and it can lead to severe epilepsy and permanent brain damage. It has been demonstrated that functional mutations of glutamate dehydrogenase (GDH), an enzyme in the mitochondrial matrix, are responsible for the HHS. Thus, GDH has become a promising target for the small molecule therapeutic intervention of HHS. Several medicinal chemistry studies are currently aimed at GDH, however, to date, none of the compounds reported has been entered clinical trials. This perspective summarizes the progress in the discovery and development of GDH inhibitors, including the pathogenesis of HHS, potential binding sites, screening methods, and research models. Future therapeutic perspectives are offered to provide a reference for discovering potent GDH modulators and encourage additional research that will provide more comprehensive guidance for drug development.

A sensitive EZMTT method provides microscale, quantitative and high-throughput evaluation of drug efficacy in the treatment of Mycobacterium tuberculosis infectious diseases.

Drug resistance has become a serious public health problem in mycobacterial infectious diseases. Here, we investigated a water soluble tetrazolium salt (EZMTT)-based detection method to provide an easy, safe and quantitative antimycobacterial susceptibility test (AMST) method, especially for targeting early detection of loss of drug susceptibility in mycobacteria. After a single addition of the EZMTT detection reagent at the inoculation of mycobacteria culture, the AMST was continuously analyzed in a sealed 96-well plate (100 µl), or a sealed tube to ensure biosafety. Using Mycobacterium tuberculosis H37Ra as the model strain, the EZMTT assay was developed with high reproducibility (Z factor of 0.64) for facile measurements of growth and drug susceptibility. In the comparative AMST study, the 7-day EZMTT method identified not only the same set of drug resistance as the other two methods (the 30-day traditional Löwenstein Jensen solid medium assay and the 10-14 day 8 ml Mycobacteria Growth Indicator Tube liquid method), but also additional strains with loss of drug susceptibility. In conclusion, we demonstrated that the EZMTT-based AMST assay in a sealed microtiter plate has great potential for routine use in medical diagnosis and drug screening to battle the unmet medical need in the treatment of multi- and extensive-drug resistant mycobacteria.

FITC-labeled d-glucose analog is suitable as a probe for detecting insulin-dependent glucose uptake.

The detection of the insulin-dependent glucose uptake is a vital part in the research of diabetes. To establish a sensitive assay for measuring glucose uptake in living cells, we synthesized a FITC linked d-glucosamine 2 as a probe. 2 was obtained by the reaction of commercially available d-glucosamine hydrochloride and FITC and was determined as a single anomeric form by 1H NMR and 13C NMR. 2 exhibited good water solubility and stability. An uptake assay in HepG2 cells with or without insulin demonstrated that FITC showed strong cellular uptake, whereas uptake of 2 is much less but is insulin dependent. This suggests that 2 is specifically transported into cells through a receptor that is regulated by insulin and has potential application in screening of compounds or genes that regulate the insulin-dependence in cell-based assays.