Search

Objectives: We evaluated the ability and accuracy of preoperative identification and localization of sentinel lymph nodes (SLNs) using intradermal injection of ultrasound contrast agent. Materials and methods: Prospectively recruited 191 early breast cancer patients with clinically negative axillary lymph nodes (ALNs). All participants received intradermal injection of microbubble contrast agent. Following the identification and localization of SLNs using contrast-enhanced ultrasound (CEUS), Markers were deployed in the SLNs US-guided. Subsequently, the SLNs with Markers were stained and marked with a suspension of nano-carbon US-guided to assist in intraoperative localization of SLNs. Standard SLNB with methylene blue tracing was performed intraoperatively to assess the consistency between the two methods of SLNs localization, thereby determining the ability and accuracy of CEUS in identifying and localizing SLNs. Results: A total of 179 patients were included in the final evaluation analysis, in which a microbubble contrast agent was injected subcutaneously in the areolar region. A total of 201 SLNs were identified, with a median of 1 SLN per patient. Each SLN was identified in 157 patients, and two SLNs were identified in 22 patients. Among the 201 SLNs from the 179 patients, the proportion that could be individually matched between CEUS and the blue dye method was 95.5% (192/201), and the consistency evaluation in SLNs identification between CEUS and blue dye staining was excellent (Kappa value = 0.62, P < 0.001). Conclusion: The consistency of identification and localization of SLNs in early breast cancer patients between CEUS and the blue dye method was strong. [ABSTRACT FROM AUTHOR]

The disintegration of nanoparticles and drug release are important and imperative for nanoparticle formulations of therapeutic agents. However, quantitatively monitoring the drug release of nanomedicines is a major challenge. In this work, boron-dipyrromethene (BDP) was applied as a model drug to study the disassembly of nanoparticles and drug release. BDP dimers with disulfide and ester bonds were synthesized, and their nanoparticles were made. The accurate analysis of bond breaking in BDP nanoparticles could not be realized by using confocal laser scanning microscopy. Hence, the possible products after bond cleavage were quantified by using liquid chromatography tandem mass spectrometry (LC-MS/MS). BDP nanoparticles could be endocytosed into cancer cells, and the disulfide bonds and ester bonds were broken to promote the disassociation of nanoparticles and BDP release. Then, near-infrared BDP nanoparticles were investigated in live mice by near-infrared fluorescence imaging and LC-MS/MS. The release of BDP was low (<10%) and BDP maintained the original dimer structure in vivo, which showed that the bond breaking for BDP nanoparticles was difficult in vivo. These results could help us understand the breaking law of disulfide bonds and ester bonds in nanoparticles and are beneficial for developing practical new drug formulations. [ABSTRACT FROM AUTHOR]

Subalpine forests provide crucial ecosystem services and are increasingly threatened by human alterations like bare-cut slopes from highway construction. External soil spray seeding (ESSS) is often employed to restore these slopes, but the cement it introduces can negatively affect soil fungi, which are vital for the ecological sustainability of restored slopes. Despite previous extensive discussions about ESSS-restored slopes, fungal dynamics and their underlying ecological mechanisms during ESSS-based restorations still remain elusive. Here, we conducted a 196-day simulation experiment using natural soils from a subalpine forest ecosystem. By using nuclear ribosomal internal transcribed spacer (ITS) sequencing, we revealed soil fungal dynamics and their ecological mechanisms during simulated ESSS-based restorations. Results showed a decline in fungal α-diversity and significant shifts in community structures from the initial day to day 46, followed by relative stabilities. These dynamics were mainly characterized by ectomycorrhizal, plant pathogenic, and saprotrophic fungi, with ectomycorrhizal fungi being depleted, while saprotrophic and pathogenic fungi showed enrichment over time. Shifts in nitrate nitrogen ( NO 3 − −N) content primarily regulated these dynamics via mediating homogeneous selections. High NO 3 − −N levels at later stages (days 46 to 196, especially day 46) might exclude those poorly adapted fungal species, resulting in great diversity loss and community shifts. Despite reduced homogeneous selections and NO 3 − −N levels after day 46, fungal communities did not show a recovery but continued to undergo changes compared to their initial states, suggesting the less resilient of fungi during ESSS-based restorations. This study highlights the need to manage soil NO 3 − −N levels for fungal communities during ESSS-based restorations. It provides novel insights for maintaining the ecological sustainability of ESSS-restored slopes and seeking new restoration strategies for cut slopes caused by infrastructure in subalpine forests. [ABSTRACT FROM AUTHOR]

Canopy gaps can result in abiotic heterogeneities and diverse niches from gap borders to centers, potentially affecting fine root decompositions mediated by soil fungal communities. Despite extensive discussions on the relationship between soil fungi and fine root decomposition, the mechanism by which gap locations regulate fine root decomposition through the soil fungal community remains elusive. Here, we conducted an in situ field decomposition experiment of Chinese Toon (Toona sinensis) fine roots in a low-efficiency weeping cypress (Cupressus funebris) plantation forest across three microhabitats: gap centers, gap borders, and closed canopy areas. Soil fungal communities were determined using internal transcribed spacer (ITS) sequencing after two years of field incubation. Results showed that soil properties and nutrient content in residual roots varied across the three microhabitats, with the gap borders exhibiting the highest decomposition rates. While fungal α-diversity remained relatively consistent, taxonomic compositions differed significantly. Decomposition rates did not show significant correlations with soil properties, observed fungal ASVs, or overall community composition. However, they positively correlated with the relative abundance of saprotrophic Sordariomycetes, which in turn positively correlated with soil total nitrogen (with a highest correlation), peaking at the gap borders. Overall community variations were primarily driven by soil temperature and magnesium content in residual roots. Further analysis revealed high fungal community similarities and low dispersal limitations between the gap borders and closed canopy areas, with more phylogenetically clustered communities at the borders. These results demonstrate that the gap borders possess a high decomposition rate, likely due to the centralization of functions driven by soil fungi such as saprotrophs existing in the "microbial seed bank" or migrating from closed canopy areas. These findings highlight the key role of soil fungi, especially saprotrophic fungi, in fine root decomposition at the gap borders, stressing the importance of soil fungi-driven mechanisms in nutrient cycling, and also informing sustainable forest management practices. [ABSTRACT FROM AUTHOR]