An Efficient Probe-Based Quantitative PCR Assay Targeting Human-Specific DNA in ST6GALNAC3 for the Quantification of Human Cells in Preclinical Animal Models

Precise quantification of human cells in preclinical animal models by a sensitive and specific approach is warranted. The probe-based quantitative PCR (qPCR) assay as a sensitive and swift approach is suitable for the quantification of human cells by targeting human-specific DNA sequences. In this study, we developed an efficient qPCR assay targeting human-specific DNA in ST6GALNAC3 (termed ST6GAL-qPCR) for the quantification of human cells in preclinical animal models. ST6GAL-qPCR probe was synthesized with FAM and non-fluorescent quencher-minor groove binder conjugated to the 5' and 3' end of the probe, respectively. Genomic DNA from human, rhesus monkeys, cynomolgus monkeys, New Zealand White rabbits, SD rats, C57BL/6, and BALB/c mice were utilized for analyzing the specificity and sensitivity of the ST6GAL-qPCR assay. The ST6GAL-qPCR assay targeted human-specific DNA was cloned to pUCM-T vector and released by EcoR I/Hind III digestion for generating a calibration curve. Cell mixing experiment was performed to validate the ST6GAL-qPCR assay by analysis of 0.1%, 0.01%, and 0.001% of human leukocytes mixed with murine thymocytes. The ST6GAL-qPCR assay detected human DNA rather than DNA from the tested animal species. The amplification efficiency of the ST6GAL-qPCR assay was 93% and the linearity of calibration curve was R2 = 0.999. The ST6GAL-qPCR assay detected as low as 5 copies of human-specific DNA and is efficient to specially amplify as low as 30-pg human DNA in the presence of 1 μg of DNA from the tested species, respectively. The ST6GAL-qPCR assay was able to quantify as low as 0.01% of human leukocytes within murine thymocytes. This ST6GAL-qPCR assay can be used as an efficient approach for the quantification of human cells in preclinical animal models.

The state of health professions students' self-directed learning ability during online study and the factors that influence it

BACKGROUND

Universities have widely switched from traditional face-to-face classes to online instruction as a result of the epidemic. Self-directed learning is becoming the new norm for university students' learning styles. The ability of health professions students to learn independently during online study directly impacts the effectiveness of online medical education. The ability to learn on their own initiative may be affected by health professions students' professional identities, defined as their positive perceptions, evaluations, emotional experiences, and identity as professionals related to medicine. This study aimed to look into the current status and the factors that influence health professions students' self-directed learning ability (SDLA) during online study and its relationship with professional identity.

METHODS

This study was conducted from September to November 2022 at a medical school in East China. An online questionnaire was used to collect participants' status of online learning, self-directed learning ability (SDLA), and professional identity.

RESULTS

One thousand two hundred ninety-eight health professions students demonstrated intermediate self-directed learning ability during online study. In terms of teacher-student interaction (F = 14.778, P < 0.001), student-student interaction (F = 15.713, P < 0.001), and learning concentration (F = 13.424, P < 0.001), there were significant differences in health professions students' self-directed learning ability. Professional identity and self-directed learning ability positively correlated (r = 0.589-0.802, P < 0.01). Academic atmosphere and professional identity were significant predictors.

CONCLUSIONS

The self-directed learning ability of health professions students while receiving instruction online is at an intermediate level and is influenced by several factors. Developing health professions students' professional identities can enhance their ability for self-directed learning.

Hyperoside mediates protection from diabetes kidney disease by regulating ROS-ERK signaling pathway and pyroptosis

Renal tubular injury is a key factor in the progression of diabetic kidney disease to end-stage renal disease. Hyperoside, a natural flavonol glycoside in various plants, is a potentially effective drug for the clinical treatment of diabetic kidney disease. However, the specific mechanisms remain unknown. Therefore, this study will explore the effect and mechanism of hyperoside on renal tubulointerstitium in diabetic kidney disease. db/db mouse (C57BL/KsJ) is a model of type 2 diabetes resulting from Leptin receptor point mutations, with the appearance of diabetic kidney disease. Therefore, db/db mice were used for in vivo experimental studies. In vitro, human renal tubular epithelial cells were incubated with bovine serum albumin to simulate the injury of renal tubular epithelial cells caused by excessive albumin in primary urine. The experimental results showed that hyperoside could improve kidney function and reduce kidney tissue damage in mice, and could inhibit oxidative stress, extracellularly regulated protein kinases 1/2 signaling activation, and pyroptosis in human renal tubular epithelial cells. Therefore, hyperoside inhibited oxidative stress by regulating the activation of the extracellularly regulated protein kinases 1/2/mitogen-activated protein kinase signaling pathway, thereby alleviating proteinuria-induced pyroptosis in renal tubular epithelial cells. This study provides novel evidence that could facilitate the clinical application of hyperoside in diabetic kidney disease treatment.