Zhihui Liu

Background: Non-neutropenic invasive pulmonary fungal disease (IPFD) is increasingly recognized but remains challenging to diagnose due to nonspecific clinical and radiological features. This retrospective, single-center study was conducted at the First Affiliated Hospital of Guangzhou University of Chinese Medicine and aimed to develop and evaluate a diagnostic model based on immuno-Serologic biomarkers for distinguishing non-neutropenic IPFD from bacterial pneumonia. Methods: A total of 157 pneumonia patients (65 non-neutropenic IPFD cases and 92 bacterial pneumonia cases) admitted to the First Affiliated Hospital of Guangzhou University of Chinese Medicine between April 2018 and December 2022 were enrolled. Least Absolute Shrinkage and Selection Operator (LASSO) regression and collinearity analysis were applied to screen key variables, followed by the development of diagnostic models using nine machine learning algorithms. Model performance was comprehensively evaluated, and temporal validation in an independent later cohort from the same center was conducted using data from 102 pneumonia patients (33 non-neutropenic IPFD and 69 bacterial pneumonia cases) admitted between January 2023 and March 2025. Results: Five biomarkers were identified as predictors: galactomannan (GM), monocyte human leukocyte antigen-DR expression (mHLA-DR), monocyte count, interleukin-6 (IL-6), and 1,3-β-D-glucan (BDG). The Light Gradient Boosting Machine (LightGBM) model demonstrated optimal performance in the validation set, with an area under the receiver operating characteristic curve (AUC) of 0.865 (95% CI: 0.728– 0.999) and accuracy of 0.781. In the test set, the model achieved an AUC of 0.810 and accuracy of 0.750. Decision curve analysis (DCA) indicated favorable net benefits across probability thresholds of 0– 1. Temporal validation yielded an AUC of 0.821 and accuracy of 0.794. Conclusion: The immuno-serologic diagnostic model exhibits strong discriminatory performance in differentiating bacterial pneumonia from non-neutropenic IPFD, highlighting its potential for clinical application.

Background: Lung cancer is the leading cause of cancer-related deaths worldwide, so research and development of potential therapeutic targets is urgent. Methods: The target gene, AKR1C2, was screened using the TCGA and FerrDb databases. The expression of AKR1C2 in lung cancer, its correlation with the clinical characteristics of patients, and the biological roles and molecular mechanisms involved were assessed by bioinformatics. The expression levels of AKR1C2 in normal lung epithelial cells and lung cancer cells were compared by qRT-PCR and Western blot. The effects of AKR1C2 knockdown on the malignant phenotype of lung cancer cells were evaluated using Transwell, wound healing, and CCK8 assays. Finally, the impact of silencing AKR1C2 on malondialdehyde, reactive oxygen species, Fe²⁺ levels, and ferroptosis-related genes in lung cancer cells were experimentally investigated. Results: AKR1C2 is highly expressed in lung adenocarcinoma tissues, and the expression level correlates with patient gender, tumor stage, lymph node metastasis, and prognosis. AKR1C2 is associated with substance metabolism, steroid hormone biosynthesis, cellular lipid metabolism, and oxidoreductase activity. AKR1C2 had high expression levels in A549 cells. AKR1C2 silencing inhibited cell viability, invasion, and migration. In A549 cells, AKR1C2 knockdown markedly raised the levels of reactive oxygen species, malondialdehyde, and Fe²⁺. The knockdown of AKR1C2 regulated the expression of ferroptosis-related genes. Conclusion: Our study demonstrates that AKR1C2 knockdown promotes ferroptosis and inhibits malignant biological behaviors in lung cancer cells.

Horseradish peroxidase (HRP) combined with its fluorescence substrates is attracting increasing attention for biochemical analysis. Amplex red is the most widely used fluorescence substrate to HRP; however, it suffers from some drawbacks, such as nonspecific responsiveness toward carboxylesterases. Discovering a new small molecular fluorescence substrate with improved sensitivity and selectivity for HRP is thus desired. Herein, three dihydrofluorescein derivatives (DCFHs) are presented to serve as HRP substrates through fluorescence turn-on methods. The most promising one, 2,7-dichloro-9-(2-(hydroxymethyl)phenyl)-9H-xanthene-3,6-diol (DCFH-1), exhibited excellent sensitivity in the detection of HRP. Moreover, DCFH-1 does not respond to carboxylesterase, thus holding advantages over Amplex red. In the further study, the detection reagent in the commercial ELISA kits was replaced with DCFH-1 to establish a new fluorescence ELISA, which works very well in the quantification of inflammatory cytokine biomarkers from in vitro models.

Pasteurella multocida, one of the major zoonotic pathogens, may cause localized cellulitis, bacteremia, septic shock, and other symptoms in people. Accidental bites or scratches in close contact between humans and cats are one of the causes of P. multocida infection in humans. The prevalence of diseases due to P. multocida in humans may be rising as a result of the popularity of cat cafes in China. However, the epidemiology of P. multocida in cat-themed cafes in South China is yet to be reported. P. multocida in 92 healthy cats from four cafes with pet-cat themes was examined in their tonsils and oral cavities. The antibiotic susceptibility of each isolate was evaluated by using the disk-susceptibility testing method. The 19 P. multocida were selected for whole-genome sequencing (WGS), together with the genome data of eight previously described clinical strains isolated from humans, and the analysis of antimicrobial resistance (AMR) determinants, capsular genotyping, MLST genotyping, and virulence gene profiles was carried out. The results showed that 48.91% of cats (45/90) were positive for P. multocida. All isolated P. multocida stains were highly resistant to erythromycin (15 μg) (100%) and nonsensitive to fluoroquinolones (5 μg) (37.38%), while they were all susceptible to penicillin (10 untis), tetracycline (30 μg), doxycycline (30 μg), and chloramphenicol (30 μg). According to WGS analysis, those with the gyrA resistance gene were all insensitive to fluoroquinolone antibiotics. Virulence gene profiles showed that the genes pfhA, nanH, and plpB were practically all present in cats compared to humans. To conclude, increased antibiotic resistance, along with virulence factors, complicates the treatment of P. multocida infection. Thus, clinical treatment for P. multocida infection should be performed more cautiously.

基于Transwell膜孔的分子筛作用，探讨利用Transwell优选人类高质量精子的可行性。 收集2023年11月–2024年5月广州中医药大学第一附属医院男科新鲜精液标本162份。分析经5 μm和8 μm孔径Transwell精子优选的差异并经透射电子显微镜（transmission electron microscope, TEM）观察微观结构差异，比较Transwell优选精子30 min、60 min、80 min后精液参数的变化，比较Transwell与密度梯度离心法（density gradient centrifugation, DGC）和上游法（swim-up methods, SU）对不同质量精子优化后精液参数的差异。本研究将精子前向运动（progressive motility, PR）百分率设定为主要结局指标，精子活力、正常精子形态率（normal sperm morphology rate, NSMR）、DNA碎片指数（DNA fragmentation index, DFI）、精子浓度及回收率设定为次要结局指标。 当孔径为5 μm、优选时间为60 min时，Transwell优选精子效果更佳。在正常精液组中，与DGC法相比，Transwell优选后的精子PR百分率中位数从77.50%升至92.05%（PPP6 mL^－1升至14.15×10⁶ mL^－1（PPPPPPP<0.01）。 Transwell优选方法在获得足够数量、活力高、形态良好以及DNA完整性较佳的精子方面表现出较好性能。这种特性使其有望成为辅助生殖技术中精选高质量精子的简便实用方法。