Objective:To establish a one-pot lyophilized detection system based on recombinase polymerase amplification (RPA) and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR-associated protein (Cas13a) technology for the rapid diagnosis of cytomegalovirus (CMV) infection in liver transplantation recipients.Methods:This study is a methodology study. CRISPR RNA (crRNA) and RPA primers were designed targeting the CMV gene sequence. Optimal RPA primer sets were screened to establish the RPA-CRISPR/Cas13a-based CMV detection system. The limit of detection (LOD) was evaluated using gradient-diluted CMV plasmid standards. Cross-reactivity was assessed using genomic DNA from common opportunistic viruses in organ transplant recipients. Lyophilized reagents were validated with CMV-negative and positive samples. P-values were computed using two-sample t-tests for pairwise comparisons and one-way ANOVA for multi-group analyses to assess fluorescence value differences. Subsequently, lyophilized reagents were employed to detect 22 plasma samples from liver transplantation recipients collected at Renji Hospital, Shanghai Jiao Tong University School of Medicine, from June 3, 2024, to May 31, 2025. The test results were then compared with those obtained using quantitative real-time polymerase chain reaction (qPCR). Consistency between the two methods was evaluated using the Kappa coefficient calculated by Kappa test.Result:The established RPA-CRISPR/Cas13a system achieved a detection sensitivity of 1 copy/reaction and exhibited no cross-reactivity with other common opportunistic viruses in organ transplantation. Lyophilized RPA-CRISPR/Cas13a reagents demonstrated performance equivalent to non-lyophilized reagents. Concordance between lyophilized reagent detection and qPCR results for 22 clinical samples was 100% (22/22).Conclusion:A lyophilized CMV detection method based on RPA-CRISPR/Cas13a technology was successfully developed and validated for convenient diagnosing CMV infection in liver transplant recipients.

Objective:To systematically compares the medial plantar venous flap (MPVF) and the lateral toe flap (LTF) reconstruction of digit-pulp defect, aiming to establish whether there exist significant differences between the 2 flaps in flap survival rate, two-point discrimination (TPD), score of Vancouver Scar Scale (VSS) and score of digit-pulp defect reconstruction evaluation.Methods:With a prospective cohort design, this study enrolled 36 patients who were admitted in Department of Hand Surgery, Longgang Eighth People's Hospital of Shenzhen for digit-pulp defects with bone or tendon exposure between January 2024 and September 2024. According to the random grouping method, participants were divided into 2 groups. The MPVF group comprised 18 patients (21 digits) of 13 males (15 digits) and 5 females (6 digits), aged 13-58 (mean 44±12) years. The MPVF group included 9 left and 12 right digits, with distribution as follows: 2 thumbs, 5 index fingers, 7 middle fingers, 5 ring fingers and 2 little fingers. The soft tissue defect area ranged from 2.0 cm × 1.0 cm to 9.2 cm × 3.3 cm (mean 6.69 cm 2± 6.69 cm 2). Flap dimensions ranged from 2.1 cm×1.1 cm to 9.5 cm×3.5 cm (mean 7.54 cm 2±7.22 cm 2). Donor sites were closed primarily or by full-thickness skin grafts harvested from the leg. The LTF group included 18 patients (21 digits) of 15 males (17 digits) and 3 females (4 digits), aged 22-62 (mean 41±12) years. The affected digits in LTF group comprised 12 left and 9 right digits, with a distribution of: 3 thumbs, 9 index fingers, 5 middle fingers, 2 ring fingers and 2 little fingers. The area of soft tissue defect ranges from 1.4 cm × 1.0 cm to 3.9 cm × 1.8 cm (mean 3.93 cm 2± 1.80 cm 2). Flap dimensions ranged from 1.5 cm×1.2 cm to 4.0 cm×1.9 cm (mean 4.52 cm 2±1.89 cm 2). Donor sites were closed primarily, or by full-thickness skin grafts harvested through extension of proximal wound extension or from calf for defect coverage. Patients were contacted for postoperative follow-up by telephone or WeChat to arrange a visit of outpatient clinic or a home visit by surgeon. Statistical analysis was conducted to compare the 2 groups regarding: gender, age and flap dimensions, flap survival rate at 2 weeks after surgery and TPD of flaps, VSS scores, and digit-pulp defect reconstruction evaluation scale scores at 4 months and 6 months postoperatively. P<0.05 indicates a statistically significant difference. Results:The comparative analysis revealed no statistically significant differences between 2 groups in baseline characteristics: gender distribution ( χ2=0.53, P=0.47), mean age ( t=0.75, P=0.46), flap dimensions ( t=1.86, P=0.08), confirming a demographic and surgical parameter equivalence in subsequent outcome comparisons ( P>0.05). All flaps survived at 2 weeks after surgery. All skin grafts at donor sites demonstrated complete viability with uneventful primary wound healing. At 4 months after surgey, the TPD in the MPVF group were 14.71 mm±1.90 mm and 7.81 mm±1.78 mm, respectively, compared to 14.48 mm±1.57 mm and 7.67 mm±1.39 mm in the LTF group at 6 months after surgery. The VSS scores were 1.67±1.11 and 1.29±0.72 for MPVF versus 1.86±1.15 and 1.38±0.81 for LTF at corresponding time points. The digit-pulp defects reconstruction evaluation scale scores showed 88.43±2.62 and 91.43±3.59 for MPVF versus 88.19±2.70 and 91.19±3.50 for LTF. Statistical analysis revealed no significant differences (all P>0.05) at 2 postoperative time points. Conclusion:The MPVF demonstrated non-inferior clinical efficacy to the LTF in reconstruction of digit-pulp defects, with comparable outcomes in flap survival rate at 2 weeks, and in TPD, VSS scores, digit-pulp defect reconstruction evaluation scale scores at 4 months and at 6 month after surgey.

Objective:To systematically compares the medial plantar venous flap (MPVF) and the lateral toe flap (LTF) reconstruction of digit-pulp defect, aiming to establish whether there exist significant differences between the 2 flaps in flap survival rate, two-point discrimination (TPD), score of Vancouver Scar Scale (VSS) and score of digit-pulp defect reconstruction evaluation.Methods:With a prospective cohort design, this study enrolled 36 patients who were admitted in Department of Hand Surgery, Longgang Eighth People's Hospital of Shenzhen for digit-pulp defects with bone or tendon exposure between January 2024 and September 2024. According to the random grouping method, participants were divided into 2 groups. The MPVF group comprised 18 patients (21 digits) of 13 males (15 digits) and 5 females (6 digits), aged 13-58 (mean 44±12) years. The MPVF group included 9 left and 12 right digits, with distribution as follows: 2 thumbs, 5 index fingers, 7 middle fingers, 5 ring fingers and 2 little fingers. The soft tissue defect area ranged from 2.0 cm × 1.0 cm to 9.2 cm × 3.3 cm (mean 6.69 cm 2± 6.69 cm 2). Flap dimensions ranged from 2.1 cm×1.1 cm to 9.5 cm×3.5 cm (mean 7.54 cm 2±7.22 cm 2). Donor sites were closed primarily or by full-thickness skin grafts harvested from the leg. The LTF group included 18 patients (21 digits) of 15 males (17 digits) and 3 females (4 digits), aged 22-62 (mean 41±12) years. The affected digits in LTF group comprised 12 left and 9 right digits, with a distribution of: 3 thumbs, 9 index fingers, 5 middle fingers, 2 ring fingers and 2 little fingers. The area of soft tissue defect ranges from 1.4 cm × 1.0 cm to 3.9 cm × 1.8 cm (mean 3.93 cm 2± 1.80 cm 2). Flap dimensions ranged from 1.5 cm×1.2 cm to 4.0 cm×1.9 cm (mean 4.52 cm 2±1.89 cm 2). Donor sites were closed primarily, or by full-thickness skin grafts harvested through extension of proximal wound extension or from calf for defect coverage. Patients were contacted for postoperative follow-up by telephone or WeChat to arrange a visit of outpatient clinic or a home visit by surgeon. Statistical analysis was conducted to compare the 2 groups regarding: gender, age and flap dimensions, flap survival rate at 2 weeks after surgery and TPD of flaps, VSS scores, and digit-pulp defect reconstruction evaluation scale scores at 4 months and 6 months postoperatively. P<0.05 indicates a statistically significant difference. Results:The comparative analysis revealed no statistically significant differences between 2 groups in baseline characteristics: gender distribution ( χ2=0.53, P=0.47), mean age ( t=0.75, P=0.46), flap dimensions ( t=1.86, P=0.08), confirming a demographic and surgical parameter equivalence in subsequent outcome comparisons ( P>0.05). All flaps survived at 2 weeks after surgery. All skin grafts at donor sites demonstrated complete viability with uneventful primary wound healing. At 4 months after surgey, the TPD in the MPVF group were 14.71 mm±1.90 mm and 7.81 mm±1.78 mm, respectively, compared to 14.48 mm±1.57 mm and 7.67 mm±1.39 mm in the LTF group at 6 months after surgery. The VSS scores were 1.67±1.11 and 1.29±0.72 for MPVF versus 1.86±1.15 and 1.38±0.81 for LTF at corresponding time points. The digit-pulp defects reconstruction evaluation scale scores showed 88.43±2.62 and 91.43±3.59 for MPVF versus 88.19±2.70 and 91.19±3.50 for LTF. Statistical analysis revealed no significant differences (all P>0.05) at 2 postoperative time points. Conclusion:The MPVF demonstrated non-inferior clinical efficacy to the LTF in reconstruction of digit-pulp defects, with comparable outcomes in flap survival rate at 2 weeks, and in TPD, VSS scores, digit-pulp defect reconstruction evaluation scale scores at 4 months and at 6 month after surgey.

Objective:To establish a one-pot lyophilized detection system based on recombinase polymerase amplification (RPA) and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR-associated protein (Cas13a) technology for the rapid diagnosis of cytomegalovirus (CMV) infection in liver transplantation recipients.Methods:This study is a methodology study. CRISPR RNA (crRNA) and RPA primers were designed targeting the CMV gene sequence. Optimal RPA primer sets were screened to establish the RPA-CRISPR/Cas13a-based CMV detection system. The limit of detection (LOD) was evaluated using gradient-diluted CMV plasmid standards. Cross-reactivity was assessed using genomic DNA from common opportunistic viruses in organ transplant recipients. Lyophilized reagents were validated with CMV-negative and positive samples. P-values were computed using two-sample t-tests for pairwise comparisons and one-way ANOVA for multi-group analyses to assess fluorescence value differences. Subsequently, lyophilized reagents were employed to detect 22 plasma samples from liver transplantation recipients collected at Renji Hospital, Shanghai Jiao Tong University School of Medicine, from June 3, 2024, to May 31, 2025. The test results were then compared with those obtained using quantitative real-time polymerase chain reaction (qPCR). Consistency between the two methods was evaluated using the Kappa coefficient calculated by Kappa test.Result:The established RPA-CRISPR/Cas13a system achieved a detection sensitivity of 1 copy/reaction and exhibited no cross-reactivity with other common opportunistic viruses in organ transplantation. Lyophilized RPA-CRISPR/Cas13a reagents demonstrated performance equivalent to non-lyophilized reagents. Concordance between lyophilized reagent detection and qPCR results for 22 clinical samples was 100% (22/22).Conclusion:A lyophilized CMV detection method based on RPA-CRISPR/Cas13a technology was successfully developed and validated for convenient diagnosing CMV infection in liver transplant recipients.