Dual-modality and Noninvasive Diagnostic of MNP-PEG-Mn Nanoprobe for Renal Fibrosis Based on Photoacoustic and Magnetic Resonance Imaging.

To date, imaging-guided multimodality therapy is important to improve the accuracy of the diagnosis of renal fibrosis, and nanoplatforms for imaging-guided multimodality diagnosis are gaining more and more attention. There are many limitations and deficiencies in clinical use for early-stage diagnosis of renal fibrosis, and multimodal imaging can contribute more thoroughly and provide in-detail information for effective clinical diagnosis. Melanin is an endogenous biomaterial, and we developed an ultrasmall particle size melanin nanoprobe (MNP-PEG-Mn) based on photoacoustic (PA) and magnetic resonance (MR) dual-modal imaging. MNP-PEG-Mn nanoprobe, with the average diameter about 2.7 nm, can be passively targeted for accumulation in the kidney, and it has excellent free radical scavenging and antioxidant abilities without further exacerbating renal fibrosis. Using the normal group signal as a control, the dual-modal imaging results showed that the MR imaging (MAI) and PA imaging (PAI) signals reached the strongest at 6 h when MNP-PEG-Mn entered the 7 day renal fibrosis group via the left vein of the tail end of the mice; however, the strength of the dual-modal imaging signal and the gradient of signal change were significantly weaker in the 28 day renal fibrosis group than in the 7 day renal fibrosis group and normal group. The phenomenon preliminarily indicates that as a PAI/MRI dual-modality contrast medium candidate, MNP-PEG-Mn has outstanding ability in clinical application potential.

Melanin theranostic nanoplatform as an efficient drug delivery system for imaging-guided renal fibrosis therapy.

As renal fibrosis nanotherapeutics, the endogenous biomaterial melanin not only has natural biocompatibility and biodegradability but also has inherent photoacoustic imaging ability and certain anti-inflammatory effects. These properties determine that melanin can not only as a carrier of medication but also track the biodistribution and renal uptake of drugs in vivo by photoacoustic imaging in real-time. Curcumin is a natural compound with biological activity, which has excellent ROS scavenging ability and good anti-inflammatory property. These materials appear more advantages in the development of nanoscale diagnostic and therapeutic platforms for future clinical translation. Herein, this study developed curcumin-loaded melanin nanoparticles (MNP-PEG-CUR NPs) as an efficient medication delivery system for photoacoustic imaging guidance renal fibrosis treatment. The nanoparticles are about 10 nm in size, exhibit good renal clearance efficiency, excellent photoacoustic imaging ability, and good in vitro and in vivo biocompatibility. These preliminary results indicated that MNP-PEG-CUR have clinically applicable potential as a therapeutic nanoplatform for renal fibrosis.

Efficacy of bed exercise in elderly patients after total hip arthroplasty: A retrospective study of 539 patients.

The purpose of this study was to observe the necessity of bed exercise therapy in the rehabilitation of elderly patients after hip replacement and to analyze whether bed exercise therapy has an impact on patients' psychological scores, hip function and postoperative complications. From January 2018 to January 2021, a total of 539 patients with end-stage femoral head necrosis or hip osteoarthritis were retrospectively analyzed. According to the method of postoperative rehabilitation exercise, patients were divided into 2 groups: Group A (routine gait) and Group B (bed exercise). There was no significant difference in general information between the 2 groups. There was no significant difference in baseline pain scores between patients in Group A and Group B (25.2 ±â€…9.6 vs 24.8 ±â€…10.4, P = .429). However, at 5 weeks post-operatively, the pain scores of patients in Group A were significantly higher than those in Group B (38.6 ±â€…7.7 vs 34.1 ±â€…8.1, P = .016). At 17 weeks post-operatively, the difference between Group A and Group B remained (40.9 ±â€…6.9 vs 37.5 ±â€…7.5, P = .041). Similar to the pain score, the hip function score compared between the 2 groups was significantly different at 5 weeks (39.7 ±â€…8.4 in Group A, 45.9 ±â€…9.2 in Group B, P < .001) and 17 weeks post-operatively (41.5 ±â€…7.6 in Group A, 47.2 ±â€…8.8 in Group B, P < .001). At 17 weeks post-operatively, between the 2 groups, only the range of motion (ROM) of abduction showed no significant difference. Patients in Group B exhibited a better ROM in any other movement posture. The results showed that compared with Group A, bed exercise rehabilitation training could reduce the incidence of deep venous thrombosis. This study demonstrates that bed exercise can improve the hip function and quality of life of elderly patients with total hip arthroplasty (THA) at an early postoperative stage. It can reduce the incidence of deep venous thrombosis of the lower limbs after surgery. For these patients, systematic bed exercise rehabilitation training is recommended in the early postoperative period.

Melanin-gelatin nanoparticles with both EPR effect and renal clearance for PA/MRI dual-modal imaging of tumors.

As cancer nanotherapeutics, the ideal multifunctional nanoparticles not only have the processing ability to accumulate effectively in tumors, but also can be excreted rapidly from the body via renal clearance after effective treatment. Melanin is an endogenous biological material, and gelatin has natural biocompatibility and biodegradability. Such materials are more promising in the development of diagnostic and therapeutic nanoplatform for future clinical translation. In this study, we have developed a kind of size-shrinkable PA/MRI theranostic agent based on gelatin fabricated ultrasmall melanin nanoparticles (MNPs-GNP). The MNPs-GNP nanoparticles, with a size of about 100 nm, presented good dispersibility, broadband light absorbance, negligible cellular cytotoxicity, preferable tumor accumulation by EPR-based passive targeting. The dual-modal imaging results showed that the nanoparticles have excellent photoacoustic (PA) imaging and nuclear magnetic resonance (MRI) imaging after tumor-bearing mice were intravenously injected with MNPs-GNP. Additionally, gelatin is the substrate of matrix metalloproteinase-2 (MMP-2), following with the degradation of gelatin nanoparticles by MMP-2, the large-size MNPs-GNP turns to be small-size melanin, which could mainly be excreted via renal clearance avoiding potential toxicity to body tissues. These preliminary results indicated that MNPs-GNP can overcome the dilemma between EPR and renal clearance, which has clinical application potentiality as a PA/MRI dual-modal candidate agent for cancer theranostics.