Chemo-photodynamic antitumour therapy based on Er-doped upconversion nanoparticles coated with hypocrellin B and MnO2

An antitumour chemo-photodynamic therapy nanoplatform was constructed based on phospholipid-coated NaYF4: Yb/Er upconversion nanoparticles (UCNPs). In this work, the amphiphilic block copolymer DSPE-PEG2000 was combined with the surface ligand oleic acid of the UCNPs through hydrophobic interaction to form liposomes with a dense hydrophobic layer in which the photosensitizer hypocrellin B (HB) was assembled. The coated HB formed J-aggregates, which caused a large redshift in the absorption spectrum and improved the quantum efficiency of energy transfer. Furthermore, MnO2 nanosheets grew in-situ on the liposomes through OMn coordination. Therefore, a multifunctional tumour microenvironment (TME)-responsive theranostic nanoplatform integrating photodynamic therapy (PDT) and chemodynamic therapy (CDT) was successfully developed. The results showed that this NIR-mediated chemo-photodynamic therapy nanoplatform was highly efficient for oncotherapy.

Hyperbaric Oxygen Therapy Following Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction

INTRODUCTION

Hyperbaric oxygen therapy (HBOT) is a promising treatment modality for ischemic heart disease including myocardial infarction where outcomes are frequently poor despite early revascularization.

OBJECTIVE

To compare single-photon emission computed tomography (SPECT) findings in patients undergoing primary percutaneous coronary intervention (PPCI) for ST-elevation myocardial infarction (STEMI) treated with HBOT vs. control at 6 weeks.

METHODS

In this pilot study, 24 patients were randomly allocated to HBOT (n = 13) and control groups (n = 11). Both groups underwent PPCI and were treated following the guidelines for STEMI management. The HBOT group received additional 15 and 90-minute HBOT sessions. All participants underwent SPECT at initial presentation (within 48 h of PPCI) and at follow up.

RESULTS

Baseline characteristics were similar in both groups. The number of affected SPECT segments in the HBOT group at baseline and 6 weeks were 47.1 ± 14.6% vs. 33.7 ± 16.2%, respectively, with p = 0.039, and in the control group, the number of affected segment at these times were 55.5 ± 19.5% vs. 45.9 ± 17.9%, respectively, with p = 0.090. At follow-up, a decrease in the summed rest score was noted in both groups (HBOT: 20 ± 6.0 vs. 12.7 ± 8.1; p = 0.0017; control: 23 ± 8.2 vs. 16.7 ± 6.6; p = 0.031). The left ventricular ejection fraction in the HBOT group improved from 44 ± 22.1% to 57.2 ± 15.4% (p = 0.011) and in the control group from 45.9 ± 18.2% to 55 ± 12.1% (p = 0.044).

CONCLUSIONS

HBOT use in STEMI patients was associated with an improvement in perfusion and an increase in ejection fraction following PPCI. These observations warrant a larger randomized clinical trial.