Dual-sized hollow particle incorporated fibroin thermal insulating coatings on catheter for cerebral therapeutic hypothermia

TiO2 Nanotube Implants Modified with Silk Fibroin and Mesoporous Silica Nanocomposite Coatings Enable Efficient Drug Release to Promote Osteogenesis

Enhanced bone healing within 1 week after post-titanium (Ti) dental implant surgery especially contributes to the subsequent long-term osseointegration, and the commonly used drug-loaded TiO2 nanotubes (TNTs) can promote osteogenesis yet still face the challenge of burst drug release that makes it difficult to maintain long-term effective drug concentrations and good osseointegration. Here, we prepared a double drug loading/release system of silk fibroin/mesoporous silica nanoparticles (SF/MSN) nanocomposite coating modified TNTs (TAMA) with AZD2858 (Wnt/β-catenin pathway agonist for promoting osteogenesis) as the therapeutic drug, realizing a long-term stable drug release and better osteogenesis. The increased β-sheet content of SF reduced the degradation rate of the SF/MSN coating, thus avoiding the AZD2858 burst release. The adsorption of MSN maintained the effective drug concentration more than 1 week that was especially critical for early bone healing. Under the protection of SF/MSN coating, the TAMA implant showed a well-organized spatial release of AZD2858, well enabling the osteogenic differentiation and mineralization at cellular level for up to 21 days. Animal experiments further demonstrated that the slow release of AZD2858 in the TAMA implant effectively activated the Wnt/β-catenin pathway, enabling rapid bone healing in the early stage of implantation and finally achieving the best osseointegration efficacy. Thus, this study proposed an efficient strategy for developing high-performance dental implants via the construction of a biodegradable SF/MSN coating.

MgSO4 as a novel hypothermia infusion solution promotes ischemic stroke recovery through Ca2+ regulation of neurovascular units

The neuroprotection of acute ischemic stroke (AIS) patients to alleviate the reperfusion injury is a long-standing problem. Although the intra-arterial selective cooling saline infusion (IA-SCSI) is a promising technique to improve the outcome of AIS, the clinical results are not sufficiently satisfactory. Magnesium-containing solutions such as magnesium sulfate (MgSO4) can protect cells by modulating the intracellular Ca2+ content in damaged cells, suggesting that they could be hypothermia infusion solution. In this study, we hypothesized that MgSO4, as a novel hypothermia infusion solution (IA-SCMI), can promote AIS recovery. Methods: First, IA-SCMI was performed in rats subjected to the middle cerebral artery occlusion. The effect of combined hypothermia and MgSO4 treatment on different neurovascular (NVU) cells after oxygen-glucose deprivation/reoxygenation (OGD/R) injury was examined. Results: Compared with the IA-SCSI or IA-MgSO4 infusion alone, IA-SCMI offered the best protective effect by improving neurological defects, and alleviating brain integrity damage and CBF reduction. Meanwhile, in vitro results revealed that the combination of hypothermia and MgSO4 provided maximum protection to the NVU cells, and this protective effect was mainly achieved through the regulation of Ca2+ homeostasis in different cells. Conclusion: MgSO4 may be a promising hypothermia infusion solution to facilitate the recovery of neurological function in AIS patients.

Trends and hotspots of the neuroprotection of hypothermia treatment: A bibliometric and visualized analysis of research from 1992 to 2023

AIM

Recent studies have extensively investigated hypothermia as a therapeutic approach for mitigating neural damage. Despite this, bibliometric analyses specifically focusing on this area remain scarce. Consequently, this study aims to comprehensively outline the historical framework of research and to pinpoint future research directions and trends.

METHODS

Articles spanning from 2003 to 2023, relevant to both "neuroprotection" and "hypothermia", were sourced from the Web of Science Core Collection. The CiteSpace software facilitated a comprehensive evaluation and analysis of these publications. This analysis included examining the annual productivity, collaboration among nations, institutions, and authors, as well as the network of co-cited references, authors and journals, and the co-occurrence of keywords, and their respective clusters and trends, all of which were visualized.

RESULTS

This study included 2103 articles on the neuroprotection effects of hypothermia, noting a consistent increase in publications since 1992. The United States, the University of California System, and Ji Xunming emerged as the most productive nation, institution, and author, respectively. Analysis of the top 10 co-cited publications revealed that seven articles focused on the effects of hypothermia in infants with hypoxic-ischemic encephalopathy, while three studies addressed cardiac arrest. Shankaran S and the journal Stroke were the most frequently co-cited author and journal, respectively. Keyword cluster analysis identified ischemic stroke as the primary focus of hypothermia therapy historically, with cardiac arrest and neonatal hypoxic-ischemic encephalopathy emerging as current research foci.

CONCLUSIONS

Recent studies on the neuroprotective effects of hypothermia in cardiac arrest and neonatal hypoxic-ischemic encephalopathy suggest that hypothermia may mitigate neural damage associated with these conditions. However, the application of hypothermia in the treatment of ischemic stroke remains confined to animal models and in vitro studies, with a notable absence of evidence from multicenter randomized controlled trials (RCTs). Further research is required to address this gap.

Nanothermometry for cellular temperature monitoring and disease diagnostics

Body temperature variations, including the generation, transfer, and dissipation of heat, play an important role throughout life and participate in all biological events. Cellular temperature information is an indispensable link in the comprehensive understanding of life science processes, but traditional testing strategies cannot provide sufficient information due to their low precision and inefficient cellular‐entrance. In recent years, with the help of luminescent nanomaterials, a variety of new thermometers have been developed to achieve real‐time temperature measurement at the micro/nano scale. In this review, we summarized the latest advances in several nanoparticles for cellular temperature detection and their related applications in revealing cell metabolism and disease diagnosis. Furthermore, this review proposed a few challenges for the nano‐thermometry, expecting to spark novel thought to push forward its preclinical and translational uses.

Multifunctional wet-adhesive chitosan/acrylic conduit for sutureless repair of peripheral nerve injuries

The incidence of peripheral nerve injury (PNI) is high worldwide, and a poor prognosis is common. Surgical closure and repair of the affected area are crucial to ensure the effective treatment of peripheral nerve injuries. Despite being the standard treatment approach, reliance on sutures to seal the severed nerve ends introduces several limitations and restrictions. This technique is intricate and time-consuming, and the application of threading and punctate sutures may lead to tissue damage and heightened tension concentrations, thus increasing the risk of fixation failure and local inflammation. This study aimed to develop easily implantable chitosan-based peripheral nerve repair conduits that combine acrylic acid and cleavable N-hydroxysuccinimide to reduce nerve damage during repair. In ex vivo tissue adhesion tests, the conduit achieved maximal interfacial toughness of 705 J m-2 ± 30 J m-2, allowing continuous bridging of the severed nerve ends. Adhesive repair significantly reduces local inflammation caused by conventional sutures, and the positive charge of chitosan disrupts the bacterial cell wall and reduces implant-related infections. This promises to open new avenues for sutureless nerve repair and reliable medical implants.