PURPOSE: To screen laboratory markers with predictive value in early spinal surgical site infections (SSI) that are diagnosed within 30 days postoperatively. METHODS: Patients who underwent surgical treatment for internal spinal fixation between March 2022 and March 2023 in our hospital were retrospectively studied. The inclusion criteria were aged >18 years, undergoing internal fixation surgery, complete medical records with >30 days of postoperative follow-up, diagnosis was made within 30 days postoperatively, and an informed consent form was obtained. The exclusion criteria were abnormal white blood cell count or neutrophil percentage in the preoperative blood routine and combined diseases that may affect the C-reactive protein (CRP) or procalcitonin (PCT) values, including lower respiratory tract infection, renal insufficiency, and liver disease. We collected patients' personal information, surgical information, and blood laboratory data, including CRP, PCT, lymphocyte-neutrophil ratio, platelet-neutrophil ratio, and routine blood tests on preoperative and postoperative days 3, 5, and 7, from these patients. These data were statistically analyzed to determine which laboratory markers were statistically significant. The diagnostic value and optimal diagnostic threshold of these laboratory markers were further determined by receiver operating characteristic curve analysis. RESULTS: A total of 106 patients were enrolled in this study, of whom 8 patients were diagnosed with early SSI. A total of 4 laboratory markers were screened, namely, CRP on postoperative day 7 (optimal diagnostic threshold of ≥64.1 mg/L, sensitivity of 100%, specificity of 76.5%, area under the curve (AUC) of 0.908), PCT on postoperative day 7 (optimal diagnostic threshold of ≥0.2 ng/mL, sensitivity of 87.5%, specificity of 94.1%, AUC of 0.967), lymphocyte count on postoperative day 5 (optimal diagnostic threshold of ≤0.67 × 10⁹/L, sensitivity of 50%, specificity of 95.9%, AUC of 0.760), and lymphocyte count on postoperative day 7 (optimal diagnostic threshold of ≤1.32 × 10⁹/L, sensitivity of 87.5%, specificity of 55.1%, AUC of 0.721). CONCLUSION We concluded that CRP and PCT levels on postoperative day 7 and lymphocyte counts on postoperative days 5 and 7 are useful markers in screening for early spinal SSI.
Humans ; Retrospective Studies ; Male ; Female ; Biomarkers/blood* ; Middle Aged ; C-Reactive Protein/analysis* ; Surgical Wound Infection/blood* ; Procalcitonin/blood* ; Adult ; Aged ; Postoperative Period ; ROC Curve ; Predictive Value of Tests ; Spine/surgery*

Objective:To study the molecular phylogeny and virulence gene profile of Francisella salimarina. Methods:Phylogenetic analysis of Francisella salimarina was performed based on the global genome data of related Francisella species on GenBank database. The consistency in phylogenetic analysis based on single marker genes (such as 16S rRNA gene, rpoB gene and mdh gene) and the core genome as compared. Virulence genes and antibiotic resistance genes were annotated using the virulence factor database (VFDB) and the Comprehensive Antibiotic Resistance Database (CARD), respectively. The virulence of Francisella salimarina was analyzed with a Galleria mellonella (greater wax moth) infection model using Francisella philomiragia ATCC 25015 T as reference strain. Results:The phylogenetic analysis revealed that Francisella salimarina was closely related to Francisella philomiragia. The phylogenetic tree based on mdh gene was highly similar to that based on the core genome. Francisella salimarina could be differentiated from other related species by 16S rRNA gene or mdh gene, with the latter being more accurate. Eight Francisella salimarina strains carried multiple virulence genes, mainly involved in secretion, adhesion, immune regulation, motility and stress survival. Moreover, beta-lactam resistance gene blaFPH was identified in all eight strains. Francisella salimarina showed high lethality in the Galleria mellonella infection model, which was similar to Francisella philomiragia ATCC 25015 T. Conclusions:Francisella salimarina was a rare pathogen with similar pathogenicity to Francisella philomiragia. The mdh gene could be used as a molecular target for rapid identification of Francisella salimarina.

ObjectiveTo observe the ultrastructural changes of Chlamydia trachomatis after treatment with azithromycin.Methods The Chlamydia trachomatis laboratory strain (D/UW-3/Cx) was cultured in McCoy cells with or without the presence of azithromycin of 0.0667,0.1340,0.1900,0.2680 and 0.3330 mg/L for 48 hours.The ultrastructural changes of host cells andChlamydia trachomatis were observed by transmission electron microscopy.ResultsAfter 48-hour culture,vesicles increased in number both inside and outside of the inclusion bodies with the rise in azithromycin concentration; there were abnormally large reticulate bodies,some of which experienced abnormal division and even necrosis or breakdown; the number of elementary bodies was decreased,while their size was enlarged,with a more wrinkled outer membrane.No inclusionbodieswereseenwhentheconcentrationofazithromycinwas0.333mg/L. Conclusions Azithromycin can induce an increment in the outer membrane of Chlamydia trachomatis,formation of vesicles,abnormal enlargement or breakdown of reticulate bodies,and a decrease in elementary bodies.

Designed experiment teaching fits well with characteristic of naval hygiene training subjects on the sea.Attention should be paid to several key points including content selection,training plan design and teaching effect evaluation.It was proved that designed experiments enhanced the practical ability of the undergraduates and significantly improved the effect of naval hygiene training subjects.