Epithelium-derived kallistatin promotes CD4+ T-cell chemotaxis to TH2-type inflammation in chronic rhinosinusitis.

BACKGROUND: The function of kallistatin in airway inflammation, particularly chronic rhinosinusitis with nasal polyps (CRSwNP), has not been elucidated. OBJECTIVE: We sought to investigate the role of kallistatin in airway inflammation. METHODS: Kallistatin and proinflammatory cytokine expression levels were detected in nasal polyps. For the in vivo studies, we constructed the kallistatin-overexpressing transgenic mice to elucidate the role of kallistatin in airway inflammation. Furthermore, the levels of plasma IgE and proinflammatory cytokines in the airways were evaluated in the kallistatin-/- rat in vivo model under a type 2 inflammatory background. Finally, the Notch signaling pathway was explored to understand the role of kallistatin in CRSwNP. RESULTS: We showed that the expression of kallistatin was significantly higher in nasal polyps than in the normal nasal mucosa and correlated with IL-4 expression. We also discovered that the nasal mucosa of kallistatin-overexpressing transgenic mice expressed higher levels of IL-4 expression, associating to TH2-type inflammation. Interestingly, we observed lower IL-4 levels in the nasal mucosa and lower total plasma IgE of the kallistatin-/- group treated with house dust mite allergen compared with the wild-type house dust mite group. Finally, we observed a significant increase in the expression of Jagged2 in the nasal epithelium cells transduced with adenovirus-kallistatin. This heightened expression correlated with increased secretion of IL-4, attributed to the augmented population of CD4+CD45+Notch1+ T cells. These findings collectively may contribute to the induction of TH2-type inflammation. CONCLUSIONS: Kallistatin was demonstrated to be involved in the CRSwNP pathogenesis by enhancing the TH2 inflammation, which was found to be associated with more expression of IL-4, potentially facilitated through Jagged2-Notch1 signaling in CD4+ T cells.

An Expeditious Neutralization Assay for Porcine Reproductive and Respiratory Syndrome Virus Based on a Recombinant Virus Expressing Green Fluorescent Protein.

Due to the extensive genetic and antigenic variation in Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), as well as its rapid mutability and evolution, PRRS prevention and control can be challenging. An expeditious and sensitive neutralization assay for PRRSV is presented to monitor neutralizing antibodies (NAbs) in serum during vaccine research. Here, a PRRSV expressing eGFP was successfully rescued with reverse genetics based on the infectious clone HuN4-F112-eGFP which we constructed. The fluorescent protein expressions of the reporter viruses remained stable for at least five passages. Based on this reporter virus, the neutralization assay can be easily used to evaluate the level of NAbs by counting cells with green fluorescence. Compared with the classical CPE assay, the newly developed assay increases sensitivity by one- to four-fold at the early antibody response stage, thus saving 2 days of assay waiting time. By using this assay to unveil the dynamics of neutralizing antibodies against PRRSV, priming immunity through either a single virulent challenge or only vaccination could produce limited NAbs, but re-infection with PRRSV would induce a faster and stronger NAb response. Overall, the novel HuN4-F112-eGFP-based neutralization assay holds the potential to provide a highly efficient platform for evaluating the next generation of PRRS vaccines.

Transbronchial cryoablation in peripheral lung parenchyma with a novel thin cryoprobe and initial clinical testing.

BACKGROUND: Transbronchial cryoablation shows potential as a local therapy for inoperable peripheral lung cancer. However, its clinical application for peripheral pulmonary lesions has not been reported yet. METHODS: An improved cryoprobe with an 8-mm-long, 1.9-mm-wide cryotip was used. Initially, the safety and effectiveness of this cryoprobe were assessed in an in vivo porcine model. Transbronchial cryoablation with 2 or 3 freeze-thaw cycles (10 min or 15 min in each freezing time) was performed in 18 pigs under CT monitoring. Radiological and pathological examinations were performed to evaluate the extent of cryoablation. Subsequently, nine patients with stage IA peripheral lung cancer or metastases underwent transbronchial cryoablation with this cryoprobe under the guidance of navigation bronchoscopy and cone-beam CT. Technical success, safety and outcomes were assessed. RESULTS: 36 cryoablation procedures were performed successfully without any major complications in the porcine model. The extent of cryoablation increased with freezing time and the number of freeze-thaw cycles, which peaked at 24 hours and then gradually decreased. Pathological results showed a change from massive haemorrhage at 24 hours to fibrous hyperplasia with chronic inflammation after 4 weeks. In the clinical trial, 10 cryoablations were performed on 9 tumours with a technical success rate of 100%. One mild treatment-related complication occurred. Of the nine tumours, seven achieved complete ablation, while two exhibited incomplete ablation and subsequent local progression at 6 months. CONCLUSION: Our initial experience indicated that transbronchial cryoablation was a safe and feasible procedure for non-surgical peripheral stage IA lung cancer or pulmonary metastases. TRIAL REGISTRATION NUMBER: ChiCTR2200061544.

Self-balancing Incremental Broad Learning System with privacy protection.

Incremental learning algorithms have been developed as an efficient solution for fast remodeling in Broad Learning Systems (BLS) without a retraining process. Even though the structure and performance of broad learning are gradually showing superiority, private data leakage in broad learning systems is still a problem that needs to be solved. Recently, Multiparty Secure Broad Learning System (MSBLS) is proposed to allow two clients to participate training. However, privacy-preserving broad learning across multiple clients has received limited attention. In this paper, we propose a Self-Balancing Incremental Broad Learning System (SIBLS) with privacy protection by considering the effect of different data sample sizes from clients, which allows multiple clients to be involved in the incremental learning. Specifically, we design a client selection strategy to select two clients in each round by reducing the gap in the number of data samples in the incremental updating process. To ensure the security under the participation of multiple clients, we introduce a mediator in the data encryption and feature mapping process. Three classical datasets are used to validate the effectiveness of our proposed SIBLS, including MNIST, Fashion and NORB datasets. Experimental results show that our proposed SIBLS can have comparable performance with MSBLS while achieving better performance than federated learning in terms of accuracy and running time.

Direct observation of photoinduced sequential spin transition in a halogen-bonded hybrid system by complementary ultrafast optical and electron probes.

A detailed understanding of the ultrafast dynamics of halogen-bonded materials is desired for designing supramolecular materials and tuning various electronic properties by external stimuli. Here, a prototypical halogen-bonded multifunctional material containing spin crossover (SCO) cations and paramagnetic radical anions is studied as a model system of photo-switchable SCO hybrid systems using ultrafast electron diffraction and two complementary optical spectroscopic techniques. Our results reveal a sequential dynamics from SCO to radical dimer softening, uncovering a key transient intermediate state. In combination with quantum chemistry calculations, we demonstrate the presence of halogen bonds in the low- and high-temperature phases and propose their role during the photoinduced sequential dynamics, underscoring the significance of exploring ultrafast dynamics. Our research highlights the promising utility of halogen bonds in finely tuning functional properties across diverse photoactive multifunctional materials.

Automatic detection of pulmonary embolism on computed tomography pulmonary angiogram scan using a three-dimensional convolutional neural network.

OBJECTIVE: To propose a convolutional neural network (EmbNet) for automatic pulmonary embolism detection on computed tomography pulmonary angiogram (CTPA) scans and to assess its diagnostic performance. METHODS: 305 consecutive CTPA scans between January 2019 and December 2021 were enrolled in this study (142 for training, 163 for internal validation), and 250 CTPA scans from a public dataset were used for external validation. The framework comprised a preprocessing step to segment the pulmonary vessels and the EmbNet to detect emboli. Emboli were divided into three location-based subgroups for detailed evaluation: central arteries, lobar branches, and peripheral regions. Ground truth was established by three radiologists. RESULTS: The EmbNet's per-scan level sensitivity, specificity, positive predictive value (PPV), and negative predictive value were 90.9%, 75.4%, 48.4%, and 97.0% (internal validation) and 88.0%, 70.5%, 42.7%, and 95.9% (external validation). At the per-embolus level, the overall sensitivity and PPV of the EmbNet were 86.0% and 61.3% (internal validation), and 83.5% and 57.5% (external validation). The sensitivity and PPV of central emboli were 89.7% and 52.0% (internal validation), and 94.4% and 43.0% (external validation); of lobar emboli were 95.2% and 76.9% (internal validation), and 93.5% and 72.5% (external validation); and of peripheral emboli were 82.6% and 61.7% (internal validation), and 80.2% and 59.4% (external validation). The average false positive rate was 0.45 false emboli per scan (internal validation) and 0.69 false emboli per scan (external validation). CONCLUSION: The EmbNet provides high sensitivity across embolus locations, suggesting its potential utility for initial screening in clinical practice.

Kilohertz droplet-on-demand serial femtosecond crystallography at the European XFEL station FXE.

X-ray Free Electron Lasers (XFELs) allow the collection of high-quality serial femtosecond crystallography data. The next generation of megahertz superconducting FELs promises to drastically reduce data collection times, enabling the capture of more structures with higher signal-to-noise ratios and facilitating more complex experiments. Currently, gas dynamic virtual nozzles (GDVNs) stand as the sole delivery method capable of best utilizing the repetition rate of megahertz sources for crystallography. However, their substantial sample consumption renders their use impractical for many protein targets in serial crystallography experiments. Here, we present a novel application of a droplet-on-demand injection method, which allowed operation at 47 kHz at the European XFEL (EuXFEL) by tailoring a multi-droplet injection scheme for each macro-pulse. We demonstrate a collection rate of 150 000 indexed patterns per hour. We show that the performance and effective data collection rate are comparable to GDVN, with a sample consumption reduction of two orders of magnitude. We present lysozyme crystallographic data using the Large Pixel Detector at the femtosecond x-ray experiment endstation. Significant improvement of the crystallographic statistics was made by correcting for a systematic drift of the photon energy in the EuXFEL macro-pulse train, which was characterized from indexing the individual frames in the pulse train. This is the highest resolution protein structure collected and reported at the EuXFEL at 1.38 Å resolution.

Structural Evolution of Photoexcited Methylcobalamin toward a CarH-like Metastable State: Evidence from Time-Resolved X-ray Absorption and X-ray Emission.

CarH is a protein photoreceptor that uses a form of B12, adenosylcobalamin (AdoCbl), to sense light via formation of a metastable excited state. Aside from AdoCbl bound to CarH, methylcobalamin (MeCbl) is the only other example─to date─of photoexcited cobalamins forming metastable excited states with lifetimes of nanoseconds or longer. The UV-visible spectra of the excited states of MeCbl and AdoCbl bound to CarH are similar. We have used transient Co K-edge X-ray absorption and X-ray emission spectroscopies in conjunction with transient absorption spectroscopy in the UV-visible region to characterize the excited states of MeCbl. These data show that the metastable excited state of MeCbl has a slightly expanded corrin ring and increased electron density on the cobalt, but only small changes in the axial bond lengths.