Comparison of Heart Rate Variability between Normoxia and Hypobaric Hypoxia Exposure

This study aimed to use the sample entropy(Samp En)method to compare the difference between normoxia and hypobaric hypoxia exposure in heart rate variability.Eight healthy male volunteers were included in this research.For each subject,electrocardiography and finger pulse signal were recorded to obtain the heart rate time series.The Sp O2 signal was collected at the same time.In normoxia or hypobaric hypoxia 4300 m section,the segment of RR time series from the second5 min episode(from the 6 th to the 10 th min)was chosen for the Samp En calculation.The differences between normoxia and hypobaric hypoxia states were analyzed.Results showed that a significant difference exists in Samp En between two states(normoxia 0.54±0.05 vs hypobaric hypoxia 4300 m exposure 0.46±0.05),indicating the regulatory mechanisms of autonomic nervous system from a nonlinear perspective.

Lipoprotein-biomimetic nanostructure enables tumor-targeted penetration delivery for enhanced photo-gene therapy towards glioma

Glioma is one of the most malignant primary tumors affecting the brain.The efficacy of therapeutics for glioma is seriously compromised by the restriction of blood-brain barrier(BBB),interstitial tumor pressure of resistance to chemotherapy/radiation,and the inevitable damage to normal brain tissues.Inspired by the natural structure and properties of high-density lipoprotein(HDL),a tumor-penetrating lipoprotein was prepared by the fusion tLyP-1 to apolipoprotein A-I-mimicking peptides(D4F),together with indocyanine green(ICG)incorporation and lipophilic small interfering RNA targeted HIF-1α(siHIF)surface anchor for site-specific photo-gene therapy.tLyP-1 peptide is fused to HDL-surface to facilitate BBB permeability,tumor-homing capacity and-site accumulation of photosensitizer and siRNA.Upon NIR light irradiation,ICG not only served as real-time targeted imaging agent,but also provided toxic reactive oxygen species and local hyperthermia for glioma phototherapy.The HIF-1αsiRNA in this nanoplatform downregulated the hypoxia-induced HIF-1αlevel in tumor microenvironment and enhanced the photodynamic therapy against glioma.These studies demonstrated that the nanoparticles could not only efficiently across BBB and carry the payloads to orthotopic glioma,but also modulate tumor microenvironment,thereby inhibiting tumor growth with biosafety.Overall,this study develops a new multifunctional drug delivery system for glioma theranostic,providing deeper insights into orthotopic brain tumor imaging and treatment.