Abstract: Objective　To explore the diagnostic value and advantage of metagenomic next-generation sequencing (mNGS) in the diagnosis of Strongyloidiasis co-infected with other pathogens. Methods　According to the inclusion and exclusion criteria, the clinical data of 5 patients diagnosed with Strongyloides stercoralis in Sun Yat-sen Memorial Hospital, Sun Yat-sen University from November 2020 to October 2022 were retrospectively collected. The clinical characteristics of the patients were analyzed, and the positive rates of Strongyloides stercoralis in 6 samples from 5 patients were compared by using mNGS and liquid-based cytology microscopy, and the detection rates of Strongyloides stercoralis eggs in the feces of 5 patients were compared by using the fecal direct smear method. The consistency between mNGS and bacterial and fungal culture results of the 6 samples was analyzed and compared. Results　Three of the 5 patients were farmers. All 5 patients had underlying diseases, with fever and cough as the main clinical manifestations, and the imaging features were mostly glass shadow and density shadow. Blood routine examination showed an increase in the percentage of neutrophils in 4 of the 5 patients, and none of the 5 patients had an increase in eosinophils. Procalcitonin levels were elevated in all five patients. Among the 6 samples from the 5 patients, the detection rate of Strongyloides stercoralis detection by mNGS was 100%, and the detection rate of liquid-based cytology was 50%. The detection rate of Strongyloides stercoralis eggs using the direct fecal smear method was 20% in 5 patients. Among the 6 samples, Human betaherpesvirus 5 was detected by mNGS, and Pneumocystis jirovecii was detected in 3 samples, Aspergillus fumigates was detected in 3 samples, and Pseudomonas aeruginosa was detected in 2 samples. Except for Strongyloides stercoralis and viruses detected by mNGS, the results of routine culture were completely consistent with those of bacteria and fungi detected by mNGS in 1 sample, inconsistent in 2 samples, and partially consistent in 3 samples. Conclusions　The detection rate of Strongyloides stercoralis by mNGS may be higher than that by fecal direct smear and liquid-based cytology. Compared to conventional bacterial and fungal cultures, mNGS has a wide detection range and may be more suitable for the detection of Strongyloides stercoralis infection co-infected with other pathogens. It presents significant diagnostic advantages for mixed infections and may be used as an early diagnosis method for Strongyloides stercoralis infection.

Objective:To preliminarily investigate the effect of circIGF2BP3 on autophagy in photoaged dermal fibroblasts.Methods:Human dermal fibroblasts were isolated from circumcised foreskin tissues from 6 children in the Department of Urological Surgery, Third Affiliated Hospital of Sun Yat-sen University. An ultraviolet A (UVA) -induced photoaged human dermal fibroblast model (UVA radiation group) was established by repeated UVA radiation at a dose of 10 J/cm 2 for 14 consecutive days, and human dermal fibroblasts receiving no treatment served as control group. The photoaged cell model was verified by β-galactosidase staining, Western blot analysis for determining P21 protein expression, and cell counting kit-8 (CCK8) assay for evaluating cell viability. Moreover, Western blot analysis was performed to determine the protein expression of autophagy-related proteins P62, microtubule-associated protein 1 light chain 3 (LC3) -Ⅰand LC3-Ⅱ in photoaged human dermal fibroblasts, and real-time quantitative RCR (qRT-PCR) to verify the differential expression of circIGF2BP3 between photoaged and normal human dermal fibroblasts. Furthermore, circIGF2BP3 was biologically annotated. Some cultured primary human dermal fibroblasts were divided into 4 groups: empty vector group transfected with an empty vector, UVA + empty vector group transfected with an empty vector followed by repeated UVA radiation, circIGF2BP3 group transfected with a circIGF2BP3-overexpressing lentiviral vector, UVA + circIGF2BP3 group transfected with a circIGF2BP3-overexpressing lentiviral vector followed by repeated UVA radiation. Western blot analysis was performed to determine the expression of autophagy-related proteins. Statistical analysis was carried out by using t test, one-way analysis of variance and least significant difference- t test. Results:Compared with the control group, the UVA radiation group showed significantly increased proportions of β-galactosidase-positive cells (61.33% ± 5.78% vs. 6.37% ± 0.32%, t = 9.49, P < 0.01) and P21 expression (1.25 ± 0.03 vs. 1.00 ± 0.05, t = 4.26, P < 0.05), but significantly decreased cell viability (74.33% ± 3.48% vs. 100%, t = 7.38, P < 0.01). Moreover, the P62 expression and LC3-Ⅱ/Ⅰ ratio were significantly higher in the UVA radiation group than in the control group (both P < 0.05). The relative expression of circIGF2BP3 was 0.72 ± 0.04 in the photoaged human dermal fibroblasts, which was significantly lower than that in the normal human dermal fibroblasts (1.00 ± 0.03, t = 5.46, P < 0.01). The P62 expression and LC3-Ⅱ/Ⅰ ratio were significantly lower in the circIGF2BP3 group (0.60 ± 0.01, 0.71 ± 0.01, respectively) than in the empty vector group (1.00 ± 0.02, 1.00 ± 0.01, t = 16.25, 2.75, P < 0.01, < 0.05, respectively), and lower in the UVA + circIGF2BP3 group (1.05 ± 0.02, 2.04 ± 0.05, respectively) than in the UVA + empty vector group (1.31 ± 0.02, 2.72 ± 0.14, t = 10.493, 6.472, respectively, both P < 0.01) . Conclusion:circIGF2BP3 can regulate autophagy in UVA-induced photoaged dermal fibroblasts, which provides a new potential therapeutic target for the prevention and treatment of skin photoaging.