Ultra-sensitive fluorescent biosensor for multiple bacteria detection based on CDs/QDs@ZIF-8 and microfluidic fluidized bed

An ultra-sensitive fluorescent biosensor based on CDs/QDs@ZIF-8 and microfluidic fluidized bed was developed for rapid and ultra-sensitive detection of multiple target bacteria. The zeolitic imidazolate frameworks (ZIF-8) act as the carrier to encapsulate three kinds of fluorescence signal molecules from the CDs/QDs@ZIF-8 signal amplification system. Besides, three kinds of target pathogenic bacteria were automatically, continuously, and circularly captured by the magnetic nanoparticles (MNPs) in the microfluidic fluidized bed. The neutral Na2EDTA solution was the first time reported to not only dissolve the ZIF-8 frameworks from the MNPs-bacteria-CDs/QDs@ZIF-8 sandwich complexes, but also release the CDs/QDs from sandwich complexes with no loss of fluorescence signal. Due to the advantages of signal amplification and automated sample pretreatment, the proposed fluorescent biosensor can simultaneously detect Escherichia coli O157:H7, Salmonella paratyphi A, and Salmonella paratyphi B as low as 101 CFU/mL within 1.5 h, respectively. The mean recovery in spiked milk samples can reach 99.18%, verifying the applicability of this biosensor in detecting multiple bacteria in real samples.

Astragaloside IV (ASIV) Mediates Endothelial Progenitor Cell (EPC) Exosomal LINC01963 to Inhibit Pyroptosis and Oxidative Stress in High Glucose-impaired Endothelial Cells

BACKGROUND

Hyperglycemia is widespread in the world's population, increasing the risk of many diseases. This study aimed to explore the regulatory effect and mechanism of astragaloside IV (ASIV)-mediated endothelial progenitor cells (EPCs) exosomal LINC01963 in endothelial cells (HUVECs) impaired by high glucose.

METHODS

Morphologies of exosomes were observed by light microscope and electron microscope. Immunofluorescence was used to identify EPCs and detect the expressions of caspase-1. LINC01963 was detected by quantitative reverse transcription PCR. NLRP3, ASC, and caspase-3 were detected by Western Blot. Nanoparticle tracking analysis was carried out to analyze the exosome diameter. High-throughput sequencing was applied to screen target lncRNAs. The proliferation of endothelial cells was measured by cell counting kit-8 assay. The apoptosis level of HUVECs was detected by flow cytometry and TdT-mediated dUTP Nick-End labeling. The levels of IL- 1β, IL-18, ROS, SOD, MDA, and LDH were measured by enzyme-linked immunosorbent assay.

RESULTS

ASIV could promote the secretion of the EPC exosome. LINC01963 was obtained by high-throughput sequencing. It was observed that high glucose could inhibit the proliferation, reduce the level of SOD, the expression of NLRP3, ASC, and caspase- 1, increase the levels of IL-1β, IL-18, ROS, MDA, and LDH, and promote apoptosis of HUVECs. Whereas LINC01963 could inhibit the apoptosis of HUVECs, the increase the expression of NLRP3, ASC, and caspase-1, and decrease the levels of IL-1β, IL-18, ROS, MDA, and LDH.

CONCLUSION

EPCs exosomal LINC01963 play an inhibitory role in high glucoseinduced pyroptosis and oxidative stress of HUVECs. This study provides new ideas and directions for treating hyperglycemia and researching exosomal lncRNAs.

Endothelial Progenitor-Cell-Derived Exosomes Induced by Astragaloside IV Accelerate Type I Diabetic-wound Healing via the PI3K/AKT/mTOR Pathway in Rats

OBJECTIVE

We explore the effects of endothelial progenitor cell (EPC)-derived exosomes (EPCexos) and of astragaloside IV (ASIV)-stimulated EPCexos (ASIV-EPCexos) on type I diabetic-wound healing, and determine the basic molecular mechanisms of action.

METHODS

EPCs were exposed to different concentrations of ASIV to generate ASIV-EPCexos. A chronic-wound healing model involving streptozotocin-stimulated diabetic rats was established. These rats were treated with EPCexos, ASIV-EPCexos, rapamycin, and wortmannin. Wound healing was evaluated by direct photographic observation, hematoxylin and eosin staining, and Masson's trichrome staining.

RESULTS

ASIV treatment increased the abilities of EPCs (e.g., proliferation), as well as exosome secretion. EPCexo showed a "cup holder" like structure. Treatment with ASIV-EPCexos increased the wound-healing rate, collagen-deposition area, bromodeoxyuridine uptake, VEGF expression, and the number of CD31- and αSMA- positive cells, whereas decreased epidermal thickness and CD45 expression. The expression of the PI3K/AKT/mTOR pathway increased, whereas the expression of inflammatory factor decreased. However, rapamycin and wortmannin reversed these changes.

CONCLUSIONS

ASIV-EPCexos may accelerate type I diabetic-wound healing via the PI3K/AKT/mTOR pathway. This study may lay the foundation for new clinical treatment options for patients with type I diabetic wounds.

Invasiveness assessment by artificial intelligence against intraoperative frozen section for pulmonary nodules ≤ 3 cm

PURPOSE

To investigate the performance of an artificial intelligence (AI) algorithm for assessing the malignancy and invasiveness of pulmonary nodules in a multicenter cohort.

METHODS

A previously developed deep learning system based on a 3D convolutional neural network was used to predict tumor malignancy and invasiveness. Dataset of pulmonary nodules no more than 3 cm was integrated with CT images and pathologic information. Receiver operating characteristic curve analysis was used to evaluate the performance of the system.

RESULTS

A total of 466 resected pulmonary nodules were included in this study. The areas under the curves (AUCs) of the deep learning system in the prediction of malignancy as compared with pathological reports were 0.80, 0.80, and 0.75 for all, subcentimeter, and solid nodules, respectively. Additionally, the AUC in the AI-assisted prediction of invasive adenocarcinoma (IA) among subsolid lesions (n = 184) was 0.88. Most malignancies that were misdiagnosed by the AI system as benign diseases with a diameter measuring greater than 1 cm (26/250, 10.4%) presented as solid nodules (19/26, 73.1%) on CT. In an exploratory analysis involving nodules underwent intraoperative pathologic examination, the concordance rate in identifying IA between the AI model and frozen section examination was 0.69, with a sensitivity of 0.50 and specificity of 0.97.

CONCLUSION

The deep learning system can discriminate malignant diseases for pulmonary nodules measuring no more than 3 cm. The AI model has a high positive predictive value for invasive adenocarcinoma with respect to intraoperative frozen section examination, which might help determine the individualized surgical strategy.

Parent Acceptance toward Inactivated COVID-19 Vaccination in Children with Acute Lymphoblastic Leukemia: The Power of Oncologist and Alliance

Objectives: The current study aims to survey the willingness of parents to vaccinate their children, who are childhood acute lymphoblastic leukemia survivors (CALLS), and identify factors associated with vaccine acceptance. Methods: Parents of CALLS on/off treatment, with the general condition of being amendable to vaccination, were recruited for interviews with attending oncologists about COVID-19 vaccination acceptance from July to November 2021 in China. After controlling for socioeconomic factors, the Association of Oncologists’ recommendations and parent−oncologist alliance with acceptance status were investigated. For validation, propensity score-matched (PSM) analysis was used. Results: A total of 424 families were included in the study, with CALLS mean remission age of 5.99 ± 3.40 years. Among them, 91 (21.4%) agreed, 168 (39.6%) hesitated, and 165 (38.9%) parents disagreed with the vaccination. The most common reason that kept parents from vaccinating their children was lack of recommendations from professional personnel (84/165, 50.9%), and massive amounts of internet information (78/175, 44.6%) was the main nonhealthcare resource against vaccination. Logistic regression analysis showed that only the recommendation from the oncologist was associated with parents’ vaccine acceptance (OR = 3.17, 95% CI = 1.93−5.20), as demonstrated by PSM comparison (42 in recommendation group vs. 18 in nonrecommendation group among 114 pairs, p < 0.001). An exploratory analysis revealed that parents with a better patient−oncologist alliance had a significantly higher level of acceptance (65.6% in alliance group vs. 15.6% in nonalliance group among 32 pairs, p < 0.001). Conclusions: Due to a lack of professional recommendation resources and the potential for serious consequences, parents were generally reluctant to vaccinate their CALLS. The recommendation of oncologists, which was influenced by the parent−oncologist alliance, significantly increased acceptance. This study emphasizes the critical role of oncologists in vaccinating cancer survivors and can be used to promote COVID-19 vaccines among vulnerable populations.

Immune checkpoint blocking impact and nomogram prediction of COVID-19 inactivated vaccine seroconversion in patients with cancer: a propensity-score matched analysis

BACKGROUND

Patients with cancer on active immune checkpoint inhibitors therapy were recommended to seek prophylaxis from COVID-19 by vaccination. There have been few reports to date to discuss the impact of progression cell death-1 blockers (PD-1B) on immune or vaccine-related outcomes, and what risk factors that contribute to the serological status remains to be elucidated. The study aims to find the impact of PD-1B on vaccination outcome and investigate other potential risk factors associated with the risk of seroconversion failure.

METHODS

Patients with active cancer treatment were retrospectively enrolled to investigate the interaction effects between PD-1B and vaccination. Through propensity score matching of demographic and clinical features, the seroconversion rates and immune/vaccination-related adverse events (irAE and vrAE) were compared in a head-to-head manner. Then, a nomogram predicting the failure risk was developed with variables significant in multivariate regression analysis and validated in an independent cohort.

RESULTS

Patients (n=454) receiving either PD-1B or COVID-19 vaccination, or both, were matched into three cohorts (vac+/PD-1B+, vac+/PD-1B-, and vac-/PD-1B+, respectively), with a non-concer control group of 206 participants. 68.1% (94/138), 71.3% (117/164), and 80.5% (166/206) were seropositive in vac+/PD-1B+cohort, vac+/PD-1B- cohort, and non-cancer control group, respectively. None of irAE or vrAE was observed to be escalated in PD-1B treatment except for low-grade rash.The vaccinated patients with cancer had a significantly lower rate of seroconversion rates than healthy control. A nomogram was thus built that encompassed age, pathology, and chemotherapy status to predict the seroconversion failure risk, which was validated in an independent cancer cohort of 196 patients.

CONCLUSION

Although patients with cancer had a generally decreased rate of seroconversion as compared with the healthy population, the COVID-19 vaccine was generally well tolerated, and seroconversion was not affected in patients receiving PD-1B. A nomogram predicting failure risk was developed, including age, chemotherapy status, pathology types, and rheumatic comorbidity.

Response of the particulate matter capture ability to leaf age and pollution intensity

Differences in leaf surface microstructure characteristics can lead to differences in the ability of trees to capture suspended particulate matter (PM). The influence of changes in leaf surface microstructure caused by growth and environmental pollution on the PM capture ability is poorly understood. This study assessed the influence of growth on leaf microstructure in leaves of different ages, and the influence of pollution intensity was assessed by studying trees growing under different pollution conditions. It was found that the ability of leaves of Taxus cuspidata var., Platycladus orientalis, and Pinus tabuliformis to absorb total suspended particles (TSP), PM10, PM2.5, and PM1 increased with leaf age. The amounts of TSP and PM10 captured by P. orientalis, P. tabuliformis, Sophora japonica, Populus tomentosa, and Ginkgo biloba were higher in heavily polluted areas than in clean areas. This may be because particle capture is influenced by leaf microstructure changes. With age increasing, the root mean square roughness (Rq) of three evergreen species leaves increased. Environmental pollution will change the leaf surface microstructure and its ability to capture PM. Compared with a clean area, in a heavily polluted area, the stomatal index of the leaves decreased, stomata were occluded, the leaf wax layer was degraded, the leaf surface contained more particles, the surface texture of S. japonica and G. biloba leaves became irregular, the boundaries of the epidermal cells became more irregular, and the trichrome of S. japonica became thinner, longer, and harder. The Rq value was generally higher in the heavily polluted area, and the roughness of the abaxial surface increased more than on the adaxial surface. In the heavily polluted area, the leaf microstructure changes were the main reason for the increase in the Rq value. With the increase in leaf roughness, the amount of PM on the leaf surface increased.