Hydrogen (H2) therapy is a highly promising strategy against several diseases due to its inherent biosafety. However, the current H2 treatment modalities rely predominantly on the systemic administration of the gas, resulting in poor targeting and utilization. Furthermore, although H2 has significant anti-tumor effects, the underlying mechanisms have not yet been elucidated. Due to their ultrasmall size, nanomaterials are highly suitable drug-delivery systems with a myriad of biomedical applications. Nanocarrier-mediated H2 delivery, as well as in situ production of H2 by nanogenerators, can significantly improve targeted accumulation of the gas and accelerate the therapeutic effects. In addition, nanomaterials can be further modified to enhance passive or active accumulation at the target site. In this Perspective, we summarize the mechanism of H2 therapy and describe possibilities for combining H2 therapy with nanomaterials. We also discuss the current challenges of H2 therapy and provide some insights into this burgeoning field.
Abstract Glutathione (GSH), the most common and abundant antioxidant in the body, is particularly concentrated in cancer cells (2–10 mM). This concentration is approximately 1000 times that of normal cells, making GSH a specific tumor marker. Overexpression of GSH is critical for mapping the redox state of cancer cells. However, there are few probes and detection methods responsive to GSH that can quantitatively visualize GSH in vivo in two‐photon excitation fluorescence (TPEF) imaging mode. The experimental results show that TPEF‐GSH could not only target GSH in tumors, but also establish the quantitative relationship between TPEF signal and GSH concentration. We explored the optimal two‐photon excitation wavelength of TPEF‐GSH, the optimal cell incubation duration with TPEF‐GSH, the best imaging time point for GSH in cells, and the quantitative relationship between the TPEF signal and the changes in GSH concentrations. In zebrafish embryo and zebrafish experiments, the ratiometric value of TPEF‐GSH increased with the decrease of GSH concentration. Microinjection and co‐incubation were used to verify whether the ratiometric value could quantify endogenous GSH in tumor‐bearing zebrafish, and the obtained GSH levels were 4.66 mM and 5.16 mM, respectively. The ratio TPEF probe could accurately visualize and quantify GSH in vivo, reflecting the redox status of the tumor. The design of the ratiometric molecular probe provides a reliable strategy for the development of TPEF nanoprobe in vivo. In this article, a new GSH sensitive molecular probe, TPEF‐GSH, has been developed with good specificity and sensitivity. TPEF‐GSH was successfully used to image cancer cells in vitro and tumor‐bearing zebrafish in vivo, and to further detect GSH levels.
To compare the performance of different imaging classifiers in the prospective diagnosis of prostate diseases based on multiparameter MRI.A total of 238 patients with pathological outcomes were enrolled from September 2019 to July 2021, including 142 in the training set and 96 in the test set. After the regions of interest were manually segmented, decision tree (DT), Gaussian naive Bayes (GNB), XGBoost, logistic regression, random forest (RF) and support vector machine classifier (SVC) models were established on the training set and tested on the independent test set. The prospective diagnostic performance of each classifier was compared by using the AUC, F1-score and Brier score.In the patient-based data set, the top three classifiers of combined sequences in terms of the AUC were logistic regression (0.865), RF (0.862), and DT (0.852); RF "was significantly different from the other two classifiers (P =0.022, P =0.005), while logistic regression and DT had no statistical significance (P =0.802). In the lesions-based data set, the top three classifiers of combined sequences in terms of the AUC were RF (0.931), logistic regression (0.922) and GNB (0.922). These three classifiers were significantly different from.The results of this experiment show that radiomics has a high diagnostic efficiency for prostate lesions. The RF classifier generally performed better overall than the other classifiers in the experiment. The XGBoost and logistic regression models also had high classification value in the lesions-based data set.
Abstract MicroRNA‐21 (MiR‐21) has been confirmed to be upregulated in tumors, and its abnormal expression is closely associated with tumor occurrence. However, the traditional imaging methods are limited to qualitative imaging of miR‐21, and no effective strategy has been developed for monitoring its concentration in vivo during cancer initiation and progression. Herein, a biosensor is created utilizing a NIR‐II ratiometric fluorescent nanoprobe to quantitatively monitor dynamic alterations in miR‐21 levels in vivo. The nanoprobe (termed DCNP@DNA2@IR806) is constructed by introducing IR806 as a donor and down‐conversion nanoparticles (DCNP) as the acceptor, using DNA as linkers. Upon miR‐21‐responsive initiation of the nanoprobe, the 1550 nm fluorescent signal of DCNP stimulated by a 808 nm laser (F 1550, 808Ex ) increased because of the close proximity of IR806 to the DCNP and the subsequent non‐radiative energy transfer (NRET). Meanwhile, the 1550 nm fluorescent signal of DCNP stimulated by a 980 nm laser (F 1550, 980Ex ) remained stable because of the absence of NRET. This ratiometric NIR‐II fluorescent signal has been confirmed to be a reliable indicator of miR‐21 concentration in vivo. The strategy holds promise for further enhancing the understanding of microRNAs‐based molecular mechanisms underlying cancer progression, laying a foundation for the early diagnosis of microRNAs‐related diseases.
Abstract Bacterial infection becomes a severe threat to human life and health worldwide. Antibiotics with the ability to resist pathogenic bacteria are therefore widely used, but the misuse or abuse of antibiotics can generate multidrug‐resistant bacteria or resistant biofilms. Advanced antibacterial technologies are needed to counter the rapid emergence of drug‐resistant bacteria. With the excellent optical properties, engineerable surface chemistry, neglectable biotoxicity, gold nanocrystals are particularly attractive in biomedicine for cancer therapy and antibacterial therapy, as well as nanoprobes for bioimaging and disease diagnosis. In this perspective, gold nanocrystal‐based antibacterial performance and deep‐tissue imaging are summarized, including near‐infrared‐light excited photoacoustic imaging and fluorescence imaging through deep tissue infections. On the basis of integrating “imaging‐therapy‐targeting” in single nanotheranostic, the current challenges of imaging‐guided antibacterial and therapy based on gold nanocrystals are discussed, and some insights are provided into the gold nanocrystal‐based nanoplatform that integrates antibacterial activity and therapy. This perspective is expected to provide comprehensive guidance for diagnosing and combating bacterial infections based on gold nanostructures.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)