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Bacterial conjugation, a commonly used method to horizontally transfer functional genes from donor to recipient strains, plays an important role in the genetic manipulation of bacteria for basic research and industrial production. Successful conjugation depends on the donor‐recipient cell recognition and a tight mating junction formation. However, the efficiency of conjugative transfer is usually very low. In this work, we developed a new technique that employed DNA molecule "glue" to increase the match frequency and the interaction stability between the donor and recipient cells. We used two E. coli strains, ETZ and BL21, as a model system, and modified them with the complementary ssDNA oligonucleotides by click chemistry. The conjugation efficiency of the modified bacteria was improved more than 4 times from 10 %–46 %. This technique is simple and generalizable as it only relies on the active amino groups on the bacterial surface. It is expected to have broad applications in constructing engineered bacteria. [ABSTRACT FROM AUTHOR]

Photoactivatable carbon monoxide‐releasing molecules (CORMs), typically based on transition‐metal carbonyl complexes, have reliance on activation by UV or visible light that restricts their biomedical applications. To address this limitation, a near‐infrared (NIR)‐responsive nanoplatform is presented based on upconversion nanoparticles (UCNPs) loading with manganese carbonyl complex Mn2(CO)10 that concurrently releases CO and manganese ion (Mn2+). With the UCNPs, the more tissue‐penetrable NIR is used to locally generate UV light for photodecomposition of Mn2(CO)10 into CO and manganese oxide (MnOX), after which MnOX is reduced to Mn2+ by the overexpressed glutathione in cancer cells. Moreover, the released Mn2+ can serve as a magnetic resonance imaging contrast agent to monitor the NIR‐controlled corelease of CO and Mn2+ in real time. Therefore, this nanoplatform can provide a potential strategy for NIR‐enabled spatiotemporally release of CO and Mn2+, enhancing the controlled delivery and biomedical application of CORMs. [ABSTRACT FROM AUTHOR]

Stimulated emission depletion (STED) microscopy, as a popular super-resolution imaging technique, has been widely used in bio-structure analysis and resolving the dynamics of biological processes beyond the diffraction limit. The performance of STED critically depends on the optical properties of the fluorescent probes. Ideally, the probe should process high brightness and good photostability, and exhibit a sensitive response to the depletion beam. Organic dyes and fluorescent proteins, as the most widely used STED probes, suffer from low brightness and exhibit rapid photobleaching under a high excitation power. Recently, luminescent nanoparticles (NPs) have emerged as promising fluorescent probes in biological imaging due to their high brightness and good photostability. STED imaging using various kinds of NPs, including quantum dots, polymer dots, carbon dots, aggregation-induced emission dots, etc., has been demonstrated. This review will comprehensively review recent advances in fluorescent NP-based STED probes, discuss their advantages and pitfalls, and outline the directions for future development. [ABSTRACT FROM AUTHOR]

Background: Characteristic symptoms and signs are often absent in patients with hepatocellular carcinoma (HCC). As a result, many patients are not diagnosed until their tumors have grown to large (> 5cm) or huge sizes (> 10cm). Liver resection has traditionally been reserved for patients with small HCC, but more recently it is being used for patients with large and huge tumors. The aim of this study was to determine risk predictors of recurrence, patterns of recurrence, and survival rates for large and huge HCC patients who underwent curative liver resection. Materials and methods: We retrospectively identified a subgroup of patients who underwent liver resection for HCC with diameters 5 cm or larger. Overall survival (OS) and recurrence‐free survival (RFS) rates were calculated using the Kaplan–Meier method. Univariate and multivariate Cox regression analyses were performed to investigate potential risk factors for recurrence and death. Results: Among 897 patients, the median follow‐up was 48 (range, 5–140) months. The 1‐, 3‐, and 5‐year RFS rates were 51.6%, 36.1%, and 30.1%, respectively, and OS rates were 80.2%, 55.4%, and 47.7%, respectively. Significant independent predictors of recurrence were preoperative satellite nodule (HR = 2.25; 95% CI, 1.17–4.31; p =.02), preoperative AFP levels above 400 ng/ml (HR = 1.23; 95% CI, 1.04–1.45; p =.01), resection margins of 1 cm or less (HR = 1.21; 95% CI, 1.00–1.46; p =.047), cirrhosis (HR = 2.64; 95% CI, 2.13–3.28; p <.001), and microvascular invasion (HR = 1.71; 95% CI, 1.45–2.20; p <.001). All of these except narrow resection margin were also independent risk factors of OS. Conclusions: Hepatic resection for patients with large and huge HCC without hepatic vascular invasion, extrahepatic metastases, or severe chronic liver disease results in acceptable long‐term outcomes. [ABSTRACT FROM AUTHOR]

Bacterial conjugation, a commonly used method to horizontally transfer functional genes from donor to recipient strains, plays an important role in the genetic manipulation of bacteria for basic research and industrial production. Successful conjugation depends on the donor-recipient cell recognition and a tight mating junction formation. However, the efficiency of conjugative transfer is usually very low. In this work, we developed a new technique that employed DNA molecule "glue" to increase the match frequency and the interaction stability between the donor and recipient cells. We used two E. coli strains, ETZ and BL21, as a model system, and modified them with the complementary ssDNA oligonucleotides by click chemistry. The conjugation efficiency of the modified bacteria was improved more than 4 times from 10 %-46 %. This technique is simple and generalizable as it only relies on the active amino groups on the bacterial surface. It is expected to have broad applications in constructing engineered bacteria., (© 2024 Wiley-VCH GmbH.)

Extracellular vesicles (EVs) are small, membrane-bound structures released by various cell types into the extracellular environment, which play a crucial role in intercellular communication and the transfer of biomolecules between cells. Given their functional significance, there are intense research interests to use EVs as disease markers and drug carriers. However, EVs characterization is greatly hindered by the small size, the low biomolecule payload, and the high level of heterogeneity. To address these challenges, researchers have adopted sensitive microscopic methods such as single-molecule fluorescence imaging, single-particle dark-field imaging, surface-enhanced Raman scattering, and surface plasmon resonance imaging for single EV analysis. These techniques can detect signals from individual EVs, enabling a detailed study of the heterogeneity. Analysis of EVs cargo has provided insights into the protein/nucleic acid expression and enabled subgroup differentiation. Superresolution mapping has visualized EVs structures, and single EV tracking has offered insights into their release and uptake mechanisms. In this review, we will summarize the recent advances in optical imaging of single EVs, including the biomarkers used for EV labeling, the performance of the reported microscopic methods, and their biological findings. Finally, we will address the limitations of the existing methods and outline prospects for future development in this field., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Co-published by Nanjing University and American Chemical Society.)

Chicoric acid (CA), a natural phenolic acid extracted from chicory and the echinacea (purple coneflower) plant ( Echinacea purpurea ), has been regarded as a nutraceutical that has powerful antioxidant and antiobesity activities. We investigated the inhibitory effects of CA on systemic inflammation-induced neuroinflammation, amyloidogenesis, and cognitive impairment. C57BL/6J mice were treated with 0.05% CA in the drinking water for 45 d. The mice were then treated by intraperitoneal injection of lipopolysaccharide (LPS). It was found that CA prevented LPS-induced memory impairment and neuronal loss through behavioral tests and histological examination. Furthermore, amyloidogenesis in the CNS was detected. The results showed that CA prevented LPS-induced increases in amyloid β (1-42 specific) (Aβ 1-42 ) accumulation, levels of amyloid precursor protein, and neuronal β-secretase 1 (BACE1), as well as the equilibrium cholinergic system in mouse brain. Moreover, CA down-regulated LPS-induced glial overactivation by inhibiting the MAPK and NF-κB pathway. Consequently, CA reduced the levels of NF-κB transcriptionally regulated inflammatory mediators and cytokines such as iNOS, cyclooxygenase-2 (COX-2), IL-1β, and TNF-α in both mouse brain and BV2 microglial cells. These results demonstrated that CA alleviated memory impairment and amyloidogenesis triggered by LPS through suppressing NF-κB transcriptional pathway, suggesting that CA might be a plausible therapeutic intervention for neuroinflammation-related diseases such as Alzheimer disease.-Liu, Q., Chen, Y., Shen, C., Xiao, Y., Wang, Y., Liu, Z., Liu, X. Chicoric acid supplementation prevents systemic inflammation-induced memory impairment and amyloidogenesis via inhibition of NF-κB., (© FASEB.)