Short-term effects of air pollutants and meteorological factors on outpatients with allergic airway disease in Ningbo, China, 2015-2021

OBJECTIVES

The allergic airway disease, such as allergic rhinitis, chronic rhinosinusitis, asthma, is a general term of a range of inflammatory disorders affecting the upper and lower airways and lung parenchyma. This study aimed to investigate the short-term effects of air pollutants and meteorological factors on AAD-related daily outpatient visits.

STUDY DESIGN

An ecological study.

METHODS

Data on outpatient visits due to AAD (n = 4,554,404) were collected from the platform of the Ningbo Health Information from January 1, 2015 to December 31, 2021. A Quasi-Poisson generalized additive regression model was established to analyze the lag effects of air pollution on daily outpatient visits for AAD. Restricted cubic spline functions were used to explore the potential non-linear relationships between air pollutants and meteorological and daily outpatient visits for AAD.

RESULTS

PM2.5, PM10, SO2, NO2, or CO were associated with daily outpatient visits for AAD, and there was a significant increasing trend in the cumulative lag effects. SO2 had the largest effect at Lag07, with a 25.3% (95% CI: 21.6%-29.0%) increase in AAD for every 10 μg/m3 increase in exposure concentration. Subgroup analysis showed that the 0-18 years old age group had the strongest effects, especially for AR, and all effects were stronger in the cold season.

CONCLUSIONS

Given that patients aged 0-18 are more susceptible to environmental changes, protective measures specifically for children should be taken during dry and cold weather conditions with poor air quality.

Constraints on Ultraheavy Dark Matter Properties from Dwarf Spheroidal Galaxies with LHAASO Observations

In this Letter we try to search for signals generated by ultraheavy dark matter at the Large High Altitude Air Shower Observatory (LHAASO) data. We look for possible γ rays by dark matter annihilation or decay from 16 dwarf spheroidal galaxies in the field of view of the LHAASO. Dwarf spheroidal galaxies are among the most promising targets for indirect detection of dark matter that have low fluxes of astrophysical γ-ray background while having large amount of dark matter. By analyzing more than 700 days of observational data at LHAASO, no significant dark matter signal from 1 TeV to 1 EeV is detected. Accordingly we derive the most stringent constraints on the ultraheavy dark matter annihilation cross section up to EeV. The constraints on the lifetime of dark matter in decay mode are also derived.

Relationship between pericoronary fat-attenuation values quantified by coronary computed tomography angiography and coronary artery disease severity

AIM

To explore the relationship between pericoronary fat-attenuation index (FAI) values and coronary artery disease (CAD) severity measured using coronary computed tomography angiography (CCTA).

MATERIALS AND METHODS

This study retrospectively included 428 patients with CAD who were eligible and underwent CCTA at our hospital. CAD severity on CCTA images including obstructive stenosis and extensive lesions, and segment stenosis and involvement score (SSS, SIS), and CAD-RADS classification were assessed. FAI values for left anterior descending (LAD), left circumflex (LCX) branches, and right coronary artery (RCA) were quantified using fully automated software. The relationship between FAI values and CAD severity was assessed using univariate and multivariate regression models.

RESULTS

Univariate analyses showed that sex and current smoking were associated with elevated FAILAD and FAILCX values (all P<0.05), whereas CAD severity was not relevant (all P>0.05). Not only clinical factors such as sex, current smoking, and hypertension were associated with elevated FAIRCA, but also indicators to assess CAD severity including obstructive stenosis, SIS, and SSS were related to it (all P<0.05). Multivariate analysis demonstrated that after correcting for the effects of other conventional cardiovascular risk factors and CCTA imaging features, current smoking was an independent risk factor for elevated FAI values (odds ratio [OR] = 0.569, 0.458, and 0.517; all P<0.05), whereas that SSS (OR=1.041, P=0.027) for elevated FAIRCA values.

CONCLUSION

Following correction for conventional cardiovascular risk factors and imaging characteristics, current smoking was an independent clinical risk factor for elevated FAI values, and SSS was an independent risk factor for elevated FAIRCA values.

[Early experience with mechanical hemodynamic support for catheter ablation of malignant ventricular tachycardia]

Objective: To explore the role of mechanical hemodynamic support (MHS) in mapping and catheter ablation of patients with hemodynamically unstable ventricular tachycardia (VT), report single-center experience in a cohort of consecutive patients receiving VT ablation during MHS therapy, and provide evidence-based medical evidence for clinical practice. Methods: This was a retrospective cohort study. Patients with hemodynamically unstable VT who underwent catheter ablation with MHS at Beijing Anzhen Hospital, Capital Medical University between August 2021 and December 2023 were included. Patients were divided into rescue group and preventive group according to the purpose of treatment. Their demographic data, periprocedural details, and clinical outcomes were collected and analyzed. Results: A total of 15 patients with hemodynamically unstable VT were included (8 patients in the rescue group and 7 patients in the preventive group). The acute procedure was successful in all patients. One patient in the rescue group had surgical left ventricular assist device (LVAD) implantation, remaining 14 patients received extracorporeal membrane oxygenation (ECMO) for circulation support. ECMO decannulation was performed in 12 patients due to clinical and hemodynamic stability, of which 6 patients were decannulation immediately after surgery and the remaining patients were decannulation at 2.0 (2.5) d after surgery. Two patients in the rescue group died during the index admission due to refractory heart failure and cerebral hemorrhage. During a median follow-up of 30 d (1 d to 12 months), one patient with LVAD had one episode of ventricular fibrillation at 6 months after discharge, and no further episodes of ventricular fibrillation and/or VT occurred after treatment with antiarrhythmic drugs. No malignant ventricular arrhythmia occurred in the remaining 12 patients who were followed up. Conclusions: MHS contributes to the successful completion of mapping and catheter ablation in patients with hemodynamically unstable VT, providing desirable hemodynamic status for emergency and elective conditions.

Evidence for particle acceleration approaching PeV energies in the W51 complex

The γ-ray emission from the W51 complex is widely acknowledged to be attributed to the interaction between the cosmic rays (CRs) accelerated by the shock of supernova remnant (SNR) W51C and the dense molecular clouds in the adjacent star-forming region, W51B. However, the maximum acceleration capability of W51C for CRs remains elusive. Based on observations conducted with the Large High Altitude Air Shower Observatory (LHAASO), we report a significant detection of γ rays emanating from the W51 complex, with energies from 2 to 200 TeV. The LHAASO measurements, for the first time, extend the γ-ray emission from the W51 complex beyond 100 TeV and reveal a significant spectrum bending at tens of TeV. By combining the "π0-decay bump" featured data from Fermi-LAT, the broadband γ-ray spectrum of the W51 region can be well-characterized by a simple pp-collision model. The observed spectral bending feature suggests an exponential cutoff at ∼400 TeV or a power-law break at ∼200 TeV in the CR proton spectrum, most likely providing the first evidence of SNRs serving as CR accelerators approaching the PeV regime. Additionally, two young star clusters within W51B could also be theoretically viable to produce the most energetic γ rays observed by LHAASO. Our findings strongly support the presence of extreme CR accelerators within the W51 complex and provide new insights into the origin of Galactic CRs.

DM-Fusion: Deep Model-Driven Network for Heterogeneous Image Fusion

Heterogeneous image fusion (HIF) is an enhancement technique for highlighting the discriminative information and textural detail from heterogeneous source images. Although various deep neural network-based HIF methods have been proposed, the most widely used single data-driven manner of the convolutional neural network always fails to give a guaranteed theoretical architecture and optimal convergence for the HIF problem. In this article, a deep model-driven neural network is designed for this HIF problem, which adaptively integrates the merits of model-based techniques for interpretability and deep learning-based methods for generalizability. Unlike the general network architecture as a black box, the proposed objective function is tailored to several domain knowledge network modules to model the compact and explainable deep model-driven HIF network termed DM-fusion. The proposed deep model-driven neural network shows the feasibility and effectiveness of three parts, the specific HIF model, an iterative parameter learning scheme, and data-driven network architecture. Furthermore, the task-driven loss function strategy is proposed to achieve feature enhancement and preservation. Numerous experiments on four fusion tasks and downstream applications illustrate the advancement of DM-fusion compared with the state-of-the-art (SOTA) methods both in fusion quality and efficiency. The source code will be available soon.

SSP-Net: A Siamese-Based Structure-Preserving Generative Adversarial Network for Unpaired Medical Image Enhancement

Recently, unpaired medical image enhancement is one of the important topics in medical research. Although deep learning-based methods have achieved remarkable success in medical image enhancement, such methods face the challenge of low-quality training sets and the lack of a large amount of data for paired training data. In this article, a dual input mechanism image enhancement method based on Siamese structure (SSP-Net) is proposed, which takes into account the structure of target highlight (texture enhancement) and background balance (consistent background contrast) from unpaired low-quality and high-quality medical images. Furthermore, the proposed method introduces the mechanism of the generative adversarial network to achieve structure-preserving enhancement by jointly iterating adversarial learning. Experiments comprehensively illustrate the performance in unpaired image enhancement of the proposed SSP-Net compared with other state-of-the-art techniques.

Correlation between left atrial appendage morphology based on fractal dimension quantification and its hemodynamic parameters in patients with atrial fibrillation

AIMS

To investigate the relationship between left atrial appendage (LAA) morphology, quantified based on fractal dimension (FD), and LAA hemodynamic parameters in patients with atrial fibrillation (AF), in an effort to reveal the effect of LAA shape on blood flow.

MATERIALS AND METHODS

225 patients with AF who underwent cardiac computed tomography angiography (CTA) and transesophageal echocardiography (TEE) were enrolled. LAA morphology was quantified based on FD on cardiac CTA images, and LAA hemodynamic parameters, including injection fraction (EF), filling peak flow velocity (FV), maximum speed of emptying (PEV), and wall motion velocity (WMV), were assessed using TEE.

RESULTS

We divided the patients with AF into two groups based on a mean LAA FD of 1.32: the low FD group (n=124) and the high FD group (n=101). Compared to the low FD group, there were more patients with LAA circulatory stasis/thrombus (P=0.008) in the high FD group, as well as lower LAA FV (P=0.004), LAA PEV (P=0.007), and LAA WMV (P=0.007). LAA FD was an independent and significant determinant of LAA EF (β = -11.755, P=0.001), LAA FV (β = -17.364, P=0.004), LAA PEV (β = -18.743, P<0.001), and LAA WMV (β = -7.740, P=0.001) in multiple linear regression analysis.

CONCLUSIONS

LAA FD is an essential determinant of LAA hemodynamic parameters, suggesting that the relatively complex morphology of the LAA may influence its hemodynamics, which can correlate with embolic events.

The effects of different impeller combinations in the Sphingan WL gum fermentation process

The fermentation of the high-viscosity polysaccharide WL gum has always been associated with poor mass transfer. Appropriate impeller configurations are key factors in maintaining homogeneity and sufficient mass transfer conditions. Therefore, a flat-folded disc turbine impeller (FFDT) taking into account both the reduced cavitation effect and the increased contact area was designed. Besides, a curved cross impeller (CC) and a fishbone-shaped impeller (FS) generating axial flow were also designed. The energy consumption and efficiency of the designed impellers and eight reported impellers were evaluated through fermentation and principal component analysis (PCA). Compared to the commonly-used six-blade flat-blade disc turbine (FBDT), the ungassed power number of FFDT was reduced by 50 %. Combinations of six-blade Brumajin impeller (BM) + FFDT and CC + FFDT produced high WL gum production and viscosity (34.0 g/L, 35.50 g/L, and 62.64 Pa·s, 61.68 Pa·s, respectively) and were suitable impellers for WL biosynthesis. WL gum from BM + FFDT showed higher viscosity, viscoelasticity, and molecular weight than that from FBDT + FBDT. In addition, fewer amino acids and pyruvic acid intermediates were formed using BM + FFDT, indicating a greater metabolic flux towards WL gum synthesis. This work provided an important reference for the design of impellers in high-viscosity fermentation systems.

A novel polycyclic quinazoline and three quinolines alkaloids from marine-derived fungus trichoderma longibrachiatum QD01 with anti-bacterial and anti-quorum sensing activities

A novel polycyclic quinazoline alkaloid (1) along with one new natural quinoline alkaloid (2) and two known quinoline alkaloids (3,4) were isolated from the marine-derived fungus Trichoderma longibrachiatum QD01. Structural determinations of those isolates were established by comprehensive spectroscopic analyses and literature comparison. Single-crystal X-ray diffraction analysis of novel compound verified its structure and stereochemistry, representing the first characterised crystal structure of a trimeric-type of tetrahydroquinazoline. Compound 4 exhibited potential antibacterial and anti-quorum sensing activity against C. violaceum and C. violaceum CV026. The sub-MIC of 4 observably decreased the violacein production in C. violaceum CV026 by 55% on 15 μg/mL. Furthermore, molecular docking results revealed that 4 has stronger binding interactions with CviR receptor than ligand C6-HSL with lower binding energy of -8.68 kcal/mol. Hydrogen bond and π-π interactions formed by Trp84, Tyr88, Trp111, and Phe126 were predicted to play an important role in the inhibition against C. violaceum CV026.

LSPR sensing for in situ monitoring the Ag dissolution of Au@Ag core-shell nanoparticles in biological environments

Silver nanoparticles (AgNPs) are extensively used as an antibacterial agent, and monitoring the dissolution behavior of AgNPs in native biological environments is critical in both optimizing their performance and regulating their safety. However, current assessment methods rely on sophisticated analytical tools that are off-site and time-consuming with potential underestimations, due to complicated sample preparation. Although localized surface plasmon resonance (LSPR) sensing offers a facile method for the detection of AgNP dissolution, it is limited by low sensitivity and poor nanoparticle stability in native biological environments. Herein, we constructed a highly sensitive and stable LSPR sensor using gold-silver core-shell nanoparticles (Au@AgNPs), in combination with polymeric stabilizing agents, for the direct measurement of the Ag shell dissolution in native biological media. The high sensitivity was attributed to the acute and large LSPR shift generated by bimetallic nanoparticles. The sensor was used for the real-time monitoring of the Ag dissolution of Au@AgNPs during their co-culture with both bacteria and fibroblast cells. The media pH was found to dominate the Ag dissolution process, where Au@AgNPs exhibited bactericidal effects in the bacteria environment with relatively low pH, but they showed little toxicity towards fibroblast cells at pH 7.4. The minimum inhibition concentration of Au@AgNPs for bacterial growth was found similar to that of AgNO3 in terms of released Ag amount. Thus, stabilized Au@AgNPs not only allow the in-situ monitoring of Ag dissolution via LSPR sensing but also constitute an effective antibacterial agent with controlled toxicity, holding great potential for future biomedical and healthcare applications.

Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15  PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

Metabolic labeling-mediated visualization, capture, and inactivation of Gram-positive bacteria via biotin-streptavidin interactions

We introduce a biotinylated D-amino acid probe capable of metabolically incorporating into bacterial PG. Leveraging the robust affinity between biotin and streptavidin, the probe has demonstrated efficacy in imaging, capture, and targeted inactivation of Gram-positive bacteria through synergistic pairings with commercially available streptavidin-modified fluorescent dyes and nanomaterials. The versatility of the probe is underscored by its compatibility with a variety of commercially available streptavidin-modified reagents. This adaptability allows the probe to be applied across diverse scenarios by integrating with these commercial reagents.

Accuracy of quantitative viral secondary standards: a re-examination

Interlaboratory agreement of viral load assays depends on the accuracy and uniformity of quantitative calibrators. Previous work demonstrated poor agreement of secondary cytomegalovirus (CMV) standards with nominal values. This study re-evaluated this issue among commercially produced secondary standards for both BK virus (BKV) and CMV, using digital polymerase chain reaction (dPCR) to compare the materials from three different manufacturers. Overall, standards showed an improved agreement compared to prior work, against nominal values in both log10 copies/mL and log10 international unit (IU)/mL, with bias from manufacturer-assigned nominal values of 0.0-0.9 log10 units (either copies or IU)/mL. Standards normalized to IU and those values assigned by dPCR rather than by real-time PCR (qPCR) showed better agreement with nominal values. The latter reinforces prior conclusions regarding the utility of using such methods for quantitative value assignment in reference materials. Quantitative standards have improved over the last several years, and the remaining bias from nominal values might be further reduced by universal implementation of dPCR methods for value assignment, normalized to IU.

IMPORTANCE

Interlaboratory agreement of viral load assays depends on accuracy and uniformity of quantitative calibrators. Previous work, published in JCM several years ago, demonstrated poor agreement of secondary cytomegalovirus (CMV) standards with nominal values. This study re-evaluated this issue among commercially produced secondary standards for both BK virus (BKV) and CMV, using digital polymerase chain reaction (dPCR) to compare the materials from three different manufacturers. Overall, standards showed an improved agreement compared to prior work, against nominal values, indicating a substantial improvement in the production of accurate secondary viral standards, while supporting the need for further work in this area and for the broad adaption of international unit (IU) as a reporting standard for quantitative viral load results.

Preparation of bacterial cellulose-based antibacterial membranes with prolonged release of drugs: Emphasis on the chemical structure of drugs

Bacterial cellulose (BC) based antibacterial membranes were synthesized, including BC-cefoperazone (BC-CEF) and BC-cefoperazone sodium (BC-CEF/Na). To examine the various drug loading processes, the structure, morphology, and physical-chemical characteristics of membranes were evaluated. Results demonstrated that both types of medicines were successfully absorbed into membranes, and membranes displayed identical morphology and FT-IR peaks. BC-CEF showed lower crystalline of XRD, which was likely caused by the combination of carboxyl and hydroxyl. However, there were no drug peaks seen in the membranes, indicating no alteration of ribbon crystallization of BC. Two types of antibacterial membranes have significantly distinct drug-loading traits and drug-releasing profiles. The drug loading rate of CEF (46.4 mg/g) was significantly greater than CEF/Na (30.3 mg/g). The cumulative drug-releasing profiles showed that only BC-CEF continues to release drugs for a lengthy period up to 48 h and exhibited good antimicrobial activity against S. aureus and E. coli until 48 h. The cytotoxicity assay demonstrated the great biocompatibility of all membranes. Findings indicated that BC-CEF has the potential use as a prolonged biocide in the biomedical. The idea that BC membranes can naturally incorporate the carboxyl groups from antibiotics is also innovative and can be useful in developing of drug delivery systems.

Stimuli-Responsive Polymer-Based Nanosystems for Cancer Theranostics

Stimuli-responsive polymers can respond to internal stimuli, such as reactive oxygen species (ROS), glutathione (GSH), and pH, biological stimuli, such as enzymes, and external stimuli, such as lasers and ultrasound, etc., by changing their hydrophobicity/hydrophilicity, degradability, ionizability, etc., and thus have been widely used in biomedical applications. Due to the characteristics of the tumor microenvironment (TME), stimuli-responsive polymers that cater specifically to the TME have been extensively used to prepare smart nanovehicles for the targeted delivery of therapeutic and diagnostic agents to tumor tissues. Compared to conventional drug delivery nanosystems, TME-responsive nanosystems have many advantages, such as high sensitivity, broad applicability among different tumors, functional versatility, and improved biosafety. In recent years, a great deal of research has been devoted to engineering efficient stimuli-responsive polymeric nanosystems, and significant improvement has been made to both cancer diagnosis and therapy. In this review, we summarize some recent research advances involving the use of stimuli-responsive polymer nanocarriers in drug delivery, tumor imaging, therapy, and theranostics. Various chemical stimuli will be described in the context of stimuli-responsive nanosystems. Accordingly, the functional chemical groups responsible for the responsiveness and the strategies to incorporate these groups into the polymer will be discussed in detail. With the research on this topic expending at a fast pace, some innovative concepts, such as sequential and cascade drug release, NIR-II imaging, and multifunctional formulations, have emerged as popular strategies for enhanced performance, which will also be included here with up-to-date illustrations. We hope that this review will offer valuable insights for the selection and optimization of stimuli-responsive polymers to help accelerate their future applications in cancer diagnosis and treatment.

Antimicrobial peptides fight against Pseudomonas aeruginosa at a sub-inhibitory concentration via anti-QS pathway

The broad-spectrum antimicrobial ability of de novo designed amphiphilic antimicrobial peptides (AMPs) G(IIKK)3I-NH2 (G3) and C8-G(IIKK)2I-NH2 (C8G2) have been demonstrated. Nonetheless, their potential as anti-quorum-sensing (anti-QS) agents, particularly against the opportunistic pathogen Pseudomonas aeruginosa at subinhibitory concentrations, has received limited attention. In this study, we proved that treating P. aeruginosa PAO1 with both AMPs at subinhibitory concentrations led to significant inhibition of QS-regulated virulence factors, including pyocyanin, elastase, proteases, and bacterial motility. Additionally, the AMPs exhibited remarkable capabilities in suppressing biofilm formation and their elimination rate of mature biofilm exceeded 95%. Moreover, both AMPs substantially downregulated the expression of QS-related genes. CD analysis revealed that both AMPs induced structural alterations in the important QS-related protein LasR in vitro. Molecular docking results indicated that both peptides bind to the hydrophobic groove of the LasR dimer. Notably, upon mutating key binding sites (D5, E11, and F87) to Ala, the binding efficiency of LasR to both peptides significantly decreased. We revealed the potential of antibacterial peptides G3 and C8G2 at their sub-MIC concentrations as QS inhibitors against P. aeruginosa and elucidated their action mechanism. These findings contribute to our understanding of the therapeutic potential of these peptides in combating P. aeruginosa infections by targeting the QS system.

Deep learning for the early identification of periodontitis: a retrospective, multicentre study

AIM

To develop a deep-learning model to help general dental practitioners diagnose periodontitis accurately and at an early stage.

MATERIALS AND METHODS

First, the panoramic radiographs (PARs) from the Second Affiliated Hospital of Nanchang University were input into the convolutional neural network (CNN) architecture to establish the PAR-CNN model for healthy controls and periodontitis patients. Then, the PARs from the Affiliated Hospital of Jiangxi University of Traditional Chinese Medicine were included in the second testing set to validate the effectiveness of the model with data from two centres. Heat maps were produced using a gradient-weighted class activation mapping method to visualise the regions of interest of the model. The accuracy and time required to read the PARs were compared between the model, periodontal experts, and general dental practitioners. Areas under the receiver operating characteristic curve (AUCs) were used to evaluate the performance of the model.

RESULTS

The AUC of the PAR-CNN model was 0.843, and the AUC of the second test set was 0.793. The heat map showed that the regions of interest predicted by the model were periodontitis bone lesions. The accuracy of the model, periodontal experts, and general dental practitioners was 0.800, 0.813, and 0.693, respectively. The time required to read each PAR by periodontal experts (6.042 ± 1.148 seconds) and general dental practitioners (13.105 ± 3.153 seconds), which was significantly longer than the time required by the model (0.027 ± 0.002 seconds).

CONCLUSION

The ability of the CNN model to diagnose periodontitis approached the level of periodontal experts. Deep-learning methods can assist general dental practitioners to diagnose periodontitis quickly and accurately.

[Quality of blood smear examinations for malaria parasites in Chenzhou City after malaria elimination]

OBJECTIVE

To analyze the quality of blood smear examinations for malaria parasites in Chenzhou City, so as to provide insights into sustainable consolidation of malaria elimination achievements.

METHODS

All positive blood smears from fever patients were irregularly sampled from each county (district) of Chenzhou City from 2018 to 2022 and reexamined, and no less than 3% negative blood smears were reexamined. The preparation, dyeing, cleanliness and microscopic examination results of blood smear were reexamined, and the quality of blood smear reexaminations was assessed using a descriptive statistical method.

RESULTS

A total of 13 625 fever patients received blood smear examinations for malaria parasites in Chenzhou City from 2018 to 2022, of which 21 were positive and 13 604 were negative; 687 blood samples were reviewed, and the percentage of negative blood smear reexaminations was 4.90% (666/13 604), with a 63.51% rate of qualified negative blood smears preparation, a 67.87% rate of qualified dyeing and a 76.13% rate of qualified cleanliness, and no missing diagnosis found. There were 21 positive blood smears reexamined, and the proportions of qualified blood smears preparation, dyeing and cleanliness were all 85.71%, with 2 smears mistaking Plasmodium species (9.52%). The percentage of qualified negative blood smears preparation was 51.41% in 2022, which reduced by 31.61% in relative to that (75.17%) in 2019 (χ2 = 9.033, P < 0.05), and the percentage of qualified negative blood smears dyeing was 60.19% in 2022, which reduced by 28.82% in relative to that (84.56%) in 2019 (χ2 = 19.498, P < 0.05), while the percentage of qualified negative blood smears cleanliness was 62.96% in 2022, which reduced by 28.93% in relative to that (88.59%) in 2019 (χ2 = 23.826, P < 0.001). In addition, there were no significant differences in the proportion of qualified negative blood smears preparation (χ2 = 0.260, P > 0.05) or dyeing (χ2 = 1.094, P > 0.05) among the three years, while a significant difference was detected in the percentage of qualified negative blood smears cleanliness (χ2 = 12.175, P < 0.05).

CONCLUSIONS

No missing diagnosis was seen in blood smear examinations for malaria parasites among fever patients in Chenzhou City after malaria elimination; however, there were reductions in proportions of qualified blood smears preparation, dyeing and cleanliness. Quality control of blood smear examinations is recommended to be reinforced in key regions of Chenzhou City.

[Changes of uterine morphology and endometrial T2 signal intensity in the fibrotic repair secondary to endometrial injury]

Objective: To investigate the value of uterine morphological parameters and endometrial T2 signal intensity (T2-SI) in evaluating the degree of the fibrotic repair secondary to endometrial injury. Methods: From Sep. 2018 to Feb. 2023, this study prospectively enrolled 29 patients with fibrotic repair secondary to severe endometrial injury (severe group), 17 patients with fibrotic repair secondary to mild to moderate endometrial injury (mild to moderate group), and 40 healthy women of reproductive age (control group) in Nanjing Drum Tower Hospital. The length of uterine cavity (LUC), length of cervix and isthmus (LCI), width of upper uterine cavity (WUUC) and width of lower uterine cavity (WLUC) were measured using magnetic resonance imaging. T2-SI of endometrium and subcutaneous fat of buttocks were measured, and endometrial normalized T2-SI (nT2-SI; T2-SI of endometrium/T2-SI of subcutaneous fat of buttocks) was calculated. Statistical analyses of data were performed using one-way analysis of variance, Mann-Whitney U test, intraclass correlation coefficient, Spearman rho test, area under the receiver operating characteristic curve (AUC). Results: LUC, WUUC, WLUC and endometrial nT2-SI of severe group [(19.7±3.5) mm, (26.9±6.4) mm, (7.9±1.4) mm, 0.73±0.11, respectively] were significantly lower than those of the control group (all P<0.01), while LCI and WUUC/LUC [(51.3±7.3) mm and 1.38±0.34] were significantly higher than those of the control group (all P<0.001). LUC and WLUC of severe group were significantly lower than those of mild to moderate group [(32.4±5.1) mm and (8.8±1.2) mm; all P<0.05], while LCI and WUUC/LUC were significantly higher than those of mild to moderate group [(41.8±8.6) mm and 0.94±0.16; all P<0.001]. LUC and endometrial nT2-SI of mild to moderate group were significantly lower than those of the control group [ (32.4±5.1) vs (35.3±3.5) mm, 0.68±0.13 vs 0.80±0.12; all P<0.01]. LUC, WUUC, WLUC and endometrial nT2-SI were significantly negatively correlated to the degree of the fibrotic repair secondary to endometrial injury (Spearman rho:-0.794, -0.441, -0.471 and -0.316, respectively; all P<0.05), while LCI and WUUC/LUC were significantly positively correlated to the degree of the fibrotic repair secondary to endometrial injury (Spearman rho: 0.481 and 0.674, respectively; all P<0.05). LUC and WUUC/LUC showed high value in distinguishing severe group from the control group or mild to moderate group (all AUC>0.9, all P<0.001). Conclusion: As noninvasive and quantitative biomarkers, uterine morphological parameters and endometrial nT2-SI could evaluate the degree of the fibrotic repair secondary to endometrial injury.

An electrophilic fragment screening for the development of small molecules targeting caspase-2

Recent Alzheimer's research has shown increasing interest in the caspase-2 (Casp2) enzyme. However, the available Casp2 inhibitors, which have been pentapeptides or peptidomimetics, face challenges for use as CNS drugs. In this study, we successfully screened a 1920-compound chloroacetamide-based, electrophilic fragment library from Enamine. Our two-point dose screen identified 64 Casp2 hits, which were further evaluated in a ten-point dose-response study to assess selectivity over Casp3. We discovered compounds with inhibition values in the single-digit micromolar and sub-micromolar range, as well as up to 32-fold selectivity for Casp2 over Casp3. Target engagement analysis confirmed the covalent-irreversible binding of the selected fragments to Cys320 at the active site of Casp2. Overall, our findings lay a strong foundation for the future development of small-molecule Casp2 inhibitors.

Observation of Single-Top-Quark Production in Association with a Photon Using the ATLAS Detector

This Letter reports the observation of single top quarks produced together with a photon, which directly probes the electroweak coupling of the top quark. The analysis uses 139  fb^{-1} of 13 TeV proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider. Requiring a photon with transverse momentum larger than 20 GeV and within the detector acceptance, the fiducial cross section is measured to be 688±23(stat) _{-71}^{+75}(syst)  fb, to be compared with the standard model prediction of 515_{-42}^{+36}  fb at next-to-leading order in QCD.

[Safety and efficacy of yellow zebra guide wire exchange system in the treatment of complete upper digestive stenosis]

To investigate the efficacy and safety of yellow zebra guide wire exchange system in the treatment of complete upper digestive stenosis. To analyze the success rate and adverse events, a retrospective analysis was conducted on patients with complete digestive stenosis in Zhongda Hospital Affiliated to Southeast University from May 2019 to April 2023 and the First Affiliated Hospital of Nanjing Medical University from August 2011 to March 2015. A total of 41 patients were included, including 25 males and 16 females, aged (65±12) years (28-94 years). Among them, 40 patients were successfully inserted with yellow zebra guide wire and underwent endoscopic treatment using the outer tube replacement with hard steel wire, with 97.6% (40/41) effective rate. Eleven patients (27.5%) were accompanied by varying degrees of retrosternal pain, without complications such as bleeding or perforation.