Biosensors have become powerful tools for real-time monitoring of specific small molecules and precise control of gene expression in biological systems. High-throughput sensors for 1, 4-butanediamine biosynthesis can greatly improve the screening efficiency of high-yielding 1, 4-butanediamine strains. However, the strategies for adapting the characteristics of biosensors are still rarely studied, which limits the applicability of 1, 4-butanediamine biosensors. In this paper, we propose the development of a 1, 4-butanediamine biosensor based on the transcriptional regulator PuuR, whose homologous operator puuO is installed in the constitutive promoter P_gapA of Escherichia coli to control the expression of the downstream superfolder green fluorescent protein (sfGFP) as the reporter protein. Finally, the biosensor showed a stable linear relationship between the GFP/OD₆₀₀ value and the concentration of 1, 4-butanediamine when the concentration of 1, 4-butanediamine was 0-50 mmol/L. The promoters with different strengths in the E. coli genome were used to modify the 1, 4-butanediamine biosensor, and the functional properties of the PuuR-based 1, 4-butanediamine biosensor were explored and improved, which laid the groundwork for high-throughput screening of engineered strains highly producing 1, 4-butanediamine.
Biosensing Techniques/methods* ; Escherichia coli/metabolism* ; Promoter Regions, Genetic/genetics* ; Green Fluorescent Proteins/metabolism* ; Transcription Factors/genetics* ; Escherichia coli Proteins/genetics* ; Diamines/metabolism* ; Gene Expression Regulation, Bacterial

Objective:To discuss the clinical curative effect of the treatment of bundling bone fragment with figure-of-eight suture through double bone tunnels in the chronic bong mallet finger.Methods:A retrospective analysis was performed on patients with chronic bong mallet fingers who underwent surgery in the Department of Hand and Foot Microsurgery of Nanjing Jiangbei Hospital from May 2021 to February 2023. During the procedure, made into transverse double bone tunnels on the base of the distal phalanx with 0. 8 mm Kirschner wire, bundling bone fragment with figure-of-eight suture through double bone tunnels, then fixed with Kirschner wire elastic compression. Removal of the Kirschner wire 3 weeks after the procedure, the active flexion and extension range of the joints of the affected finger and the corresponding finger were measured at the last follow-up, then the range of motion (ROM) of the distal interphalangeal joint (DIPJ) and total action movement (TAM) of the fingers (affected and healthy finger) were recorded. The curative effects were evaluated according to the TAM system of the American Association of Hand Surgeons, including 4 grades: excellent, good, fair, and poor. SPSS 13. 0 software was used for statistical analysis of the data, and the measurement data conforming to normal distribution were expressed as Mean ± SD. The ROM of DIPJ and TAM of the affected finger were compared with the corresponding healthy finger 6 months after surgery by a paired sample t test. P<0. 05 indicates that the difference is statistically significant. Results:A total of 30 patients (30 digits) were enrolled, including 19 males and 11 females, and the age ranged from 18 to 62 years old, with an average age of 31 years old. The time from injury to operation was 24 to 65 days (mean of 35 days) . According to Wehbe and Schneider classification, there were 8 cases of type Ⅰa, 6 cases of type Ⅰb, 7 cases of type Ⅱa, 5 cases of type Ⅱb, 2 cases of type Ⅲa and 2 cases of type Ⅲb. All incisions healed well, the intraoperative blood loss was minimal, with no infection. All 30 cases were followed up for 6 to 7 months. All fractures were well aligned and healed, malformed fingers were completely corrected, and no needle tunnel infection or needle breakage were observed. At the last follow-up, the differences of the ROM of the DIPJ [ (30. 2±3. 5) °vs. (30. 4±3. 3) °, t=2. 57, P=0. 463] and the TAM [ (235. 3± 3. 6) ° vs. (237. 7± 4. 2) °, t=1. 78, P= 0. 247 ] between the affected and healthy fingers were not statistically significant. Finger function assessment: 27 cases were excellent, and 3 cases were good, and the excellent and good rate was 100%. Conclusion:Satisfactory therapeutic outcome for the treatment of chronic bong mallet finger deformity can be achieved by bundling bone fragment with figure-of-eight suture through double bone tunnels. It is an effective and practical method.

Objective:To discuss the clinical curative effect of the treatment of bundling bone fragment with figure-of-eight suture through double bone tunnels in the chronic bony mallet finger.Methods:A retrospective analysis was performed on patients with chronic bony mallet fingers who underwent surgery in the Department of Hand and Foot Microsurgery of Nanjing Jiangbei Hospital from May 2021 to February 2023. During the procedure, made into transverse double bone tunnels on the base of the distal phalanx with 0.8 mm Kirschner wire, bundling bone fragment with figure-of-eight suture through double bone tunnels, then fixed with Kirschner wire elastic compression. Removal of the Kirschner wire 3 weeks after the procedure, the active flexion and extension range of the joints of the affected finger and the corresponding finger were measured at the last follow-up, then the range of motion (ROM) of the distal interphalangeal joint (DIPJ) and total action movement (TAM) of the fingers (affected and healthy finger) were recorded. The curative effects were evaluated according to the TAM system of the American Association of Hand Surgeons, including 4 grades: excellent, good, fair, and poor. SPSS 13.0 software was used for statistical analysis of the data, and the measurement data conforming to normal distribution were expressed as Mean±SD. The ROM of DIPJ and TAM of the affected finger were compared with the corresponding healthy finger 6 months after surgery by a paired sample t-test. P<0.05 indicated that the difference was statistically significant. Results:A total of 30 patients (30 digits) were enrolled, including 19 males and 11 females, and the age ranged from 18 to 62 years old, with an average age of 31 years old. The time from injury to operation was 24 to 65 days (mean of 35 days). According to Wehbe and Schneider classification, there were 8 cases of type Ⅰa, 6 cases of type Ⅰb, 7 cases of type Ⅱa, 5 cases of type Ⅱb, 2 cases of type Ⅲa and 2 cases of type Ⅲb. All incisions healed well, the intraoperative blood loss was minimal, with no infection. All 30 cases were followed up for 6 to 7 months. All fractures were well aligned and healed, malformed fingers were completely corrected, and no needle tunnel infection or needle breakage were observed. At the last follow-up, the differences of the ROM of the DIPJ [(30.2±3.5)° vs. (30.4±3.3)°, t=2.57, P=0.463] and the TAM [(235.3±3.6)° vs. (237.7±4.2)°, t=1.78, P=0.247] between the affected and healthy fingers were not statistically significant. Finger function assessment: 27 cases were excellent, and 3 cases were good, and the excellent and good rate was 100%. Conclusion:Satisfactory therapeutic outcome for the treatment of chronic bony mallet finger deformity can be achieved by bundling bone fragment with figure-of-eight suture through double bone tunnels. It is an effective and practical method.

Objective:To discuss the clinical curative effect and feasibility of the combination therapy of the minimally invasive percutaneous quantitative suture technique eight times and Kirschner wire elastic fixation in the treatment of mallet finger.Methods:A retrospective analysis was performed on patients with tendon zone Ⅰ rupture of tendinous mallet fingers who underwent surgery in the Department of Hand and Foot Microsurgery of Nanjing Jiangbei Hospital from July 2021 to June 2023. During the procedure, firstly, the extensor digitalis tendon in the zone Ⅰ was sutured percutaneous with 3-0 thread monofilament sutures in the "quantitative 8-stitch method " according to the pre-marked number sequence of 1 to 8, and fixed at the base of the distal phalanx via a constructed bone tunnel. Secondly, the distal interphalangeal joint (DIPJ) was fixed elastically with Kirschner wire, without damage to the articular surface. Four to five weeks after the operation, the Kirschner wire was removed, and flexion and extension of the affected finger were gradually increased. At the last follow-up, the range of motion (ROM) and the total action motion (TAM) of the finger were recorded, and the healthy side of the ROM and TAM slightly differed. Finger function was evaluated following the American Association of Hand Surgeons TAM system. It was divided into four grades: excellent, good, fair and poor. SPSS 15.0 software was used for statistical analysis. Measurement data conforming to normal distribution were expressed as Mean±SD, and a paired sample t-test was used for comparison between the affected finger and the corresponding healthy finger. Results:A total of 30 patients (30 digits) were enrolled, including 19 males and 11 females with the age of (38.5±4.3) years (14 to 71 years). All were single closed injuries. Time from injury to operation was (1.1±0.4) d (3 h to 7 d). The distance of tendon break was (8.4±0.5) mm (4 to 12 mm). Mallet finger deformities were all corrected postoperatively. There were no complications such as scar, exposed suture, nail tract infection, or nail removal on the dorsal side of the affected finger. All patients were followed up for (7.5±1.3) months (6-13 months). At the last follow-up, the ROM of DIPJ of the affected finger and the corresponding healthy finger were 43.28°±2.03° and 44.15°±1.12°, respectively, with no statistical significance ( t=1.32, P=0.084). TAM of the affected finger and the corresponding healthy finger were 240.15°±5.13° and 242.13°±3.11°, respectively, with no significant difference ( t=2.12, P=0.135). According to TAM system evaluation criteria, excellent in 27 cases, good in 3 cases, excellent and good rate was 100% (30/30). Conclusion:The combination of the minimally invasive percutaneous quantitative suture technique eight times and Kirschner wire elastic fixation has a satisfactory treatment outcome in the mallet finger, and there is no damage to the DIPJ surface. It is a simple, safe, effective method with minimal invasion.

Objective:To discuss the clinical curative effect of the treatment of bundling bone fragment with figure-of-eight suture through double bone tunnels in the chronic bong mallet finger.Methods:A retrospective analysis was performed on patients with chronic bong mallet fingers who underwent surgery in the Department of Hand and Foot Microsurgery of Nanjing Jiangbei Hospital from May 2021 to February 2023. During the procedure, made into transverse double bone tunnels on the base of the distal phalanx with 0. 8 mm Kirschner wire, bundling bone fragment with figure-of-eight suture through double bone tunnels, then fixed with Kirschner wire elastic compression. Removal of the Kirschner wire 3 weeks after the procedure, the active flexion and extension range of the joints of the affected finger and the corresponding finger were measured at the last follow-up, then the range of motion (ROM) of the distal interphalangeal joint (DIPJ) and total action movement (TAM) of the fingers (affected and healthy finger) were recorded. The curative effects were evaluated according to the TAM system of the American Association of Hand Surgeons, including 4 grades: excellent, good, fair, and poor. SPSS 13. 0 software was used for statistical analysis of the data, and the measurement data conforming to normal distribution were expressed as Mean ± SD. The ROM of DIPJ and TAM of the affected finger were compared with the corresponding healthy finger 6 months after surgery by a paired sample t test. P<0. 05 indicates that the difference is statistically significant. Results:A total of 30 patients (30 digits) were enrolled, including 19 males and 11 females, and the age ranged from 18 to 62 years old, with an average age of 31 years old. The time from injury to operation was 24 to 65 days (mean of 35 days) . According to Wehbe and Schneider classification, there were 8 cases of type Ⅰa, 6 cases of type Ⅰb, 7 cases of type Ⅱa, 5 cases of type Ⅱb, 2 cases of type Ⅲa and 2 cases of type Ⅲb. All incisions healed well, the intraoperative blood loss was minimal, with no infection. All 30 cases were followed up for 6 to 7 months. All fractures were well aligned and healed, malformed fingers were completely corrected, and no needle tunnel infection or needle breakage were observed. At the last follow-up, the differences of the ROM of the DIPJ [ (30. 2±3. 5) °vs. (30. 4±3. 3) °, t=2. 57, P=0. 463] and the TAM [ (235. 3± 3. 6) ° vs. (237. 7± 4. 2) °, t=1. 78, P= 0. 247 ] between the affected and healthy fingers were not statistically significant. Finger function assessment: 27 cases were excellent, and 3 cases were good, and the excellent and good rate was 100%. Conclusion:Satisfactory therapeutic outcome for the treatment of chronic bong mallet finger deformity can be achieved by bundling bone fragment with figure-of-eight suture through double bone tunnels. It is an effective and practical method.

Objective:To discuss the clinical curative effect of the treatment of bundling bone fragment with figure-of-eight suture through double bone tunnels in the chronic bony mallet finger.Methods:A retrospective analysis was performed on patients with chronic bony mallet fingers who underwent surgery in the Department of Hand and Foot Microsurgery of Nanjing Jiangbei Hospital from May 2021 to February 2023. During the procedure, made into transverse double bone tunnels on the base of the distal phalanx with 0.8 mm Kirschner wire, bundling bone fragment with figure-of-eight suture through double bone tunnels, then fixed with Kirschner wire elastic compression. Removal of the Kirschner wire 3 weeks after the procedure, the active flexion and extension range of the joints of the affected finger and the corresponding finger were measured at the last follow-up, then the range of motion (ROM) of the distal interphalangeal joint (DIPJ) and total action movement (TAM) of the fingers (affected and healthy finger) were recorded. The curative effects were evaluated according to the TAM system of the American Association of Hand Surgeons, including 4 grades: excellent, good, fair, and poor. SPSS 13.0 software was used for statistical analysis of the data, and the measurement data conforming to normal distribution were expressed as Mean±SD. The ROM of DIPJ and TAM of the affected finger were compared with the corresponding healthy finger 6 months after surgery by a paired sample t-test. P<0.05 indicated that the difference was statistically significant. Results:A total of 30 patients (30 digits) were enrolled, including 19 males and 11 females, and the age ranged from 18 to 62 years old, with an average age of 31 years old. The time from injury to operation was 24 to 65 days (mean of 35 days). According to Wehbe and Schneider classification, there were 8 cases of type Ⅰa, 6 cases of type Ⅰb, 7 cases of type Ⅱa, 5 cases of type Ⅱb, 2 cases of type Ⅲa and 2 cases of type Ⅲb. All incisions healed well, the intraoperative blood loss was minimal, with no infection. All 30 cases were followed up for 6 to 7 months. All fractures were well aligned and healed, malformed fingers were completely corrected, and no needle tunnel infection or needle breakage were observed. At the last follow-up, the differences of the ROM of the DIPJ [(30.2±3.5)° vs. (30.4±3.3)°, t=2.57, P=0.463] and the TAM [(235.3±3.6)° vs. (237.7±4.2)°, t=1.78, P=0.247] between the affected and healthy fingers were not statistically significant. Finger function assessment: 27 cases were excellent, and 3 cases were good, and the excellent and good rate was 100%. Conclusion:Satisfactory therapeutic outcome for the treatment of chronic bony mallet finger deformity can be achieved by bundling bone fragment with figure-of-eight suture through double bone tunnels. It is an effective and practical method.

Objective:To discuss the clinical curative effect and feasibility of the combination therapy of the minimally invasive percutaneous quantitative suture technique eight times and Kirschner wire elastic fixation in the treatment of mallet finger.Methods:A retrospective analysis was performed on patients with tendon zone Ⅰ rupture of tendinous mallet fingers who underwent surgery in the Department of Hand and Foot Microsurgery of Nanjing Jiangbei Hospital from July 2021 to June 2023. During the procedure, firstly, the extensor digitalis tendon in the zone Ⅰ was sutured percutaneous with 3-0 thread monofilament sutures in the "quantitative 8-stitch method " according to the pre-marked number sequence of 1 to 8, and fixed at the base of the distal phalanx via a constructed bone tunnel. Secondly, the distal interphalangeal joint (DIPJ) was fixed elastically with Kirschner wire, without damage to the articular surface. Four to five weeks after the operation, the Kirschner wire was removed, and flexion and extension of the affected finger were gradually increased. At the last follow-up, the range of motion (ROM) and the total action motion (TAM) of the finger were recorded, and the healthy side of the ROM and TAM slightly differed. Finger function was evaluated following the American Association of Hand Surgeons TAM system. It was divided into four grades: excellent, good, fair and poor. SPSS 15.0 software was used for statistical analysis. Measurement data conforming to normal distribution were expressed as Mean±SD, and a paired sample t-test was used for comparison between the affected finger and the corresponding healthy finger. Results:A total of 30 patients (30 digits) were enrolled, including 19 males and 11 females with the age of (38.5±4.3) years (14 to 71 years). All were single closed injuries. Time from injury to operation was (1.1±0.4) d (3 h to 7 d). The distance of tendon break was (8.4±0.5) mm (4 to 12 mm). Mallet finger deformities were all corrected postoperatively. There were no complications such as scar, exposed suture, nail tract infection, or nail removal on the dorsal side of the affected finger. All patients were followed up for (7.5±1.3) months (6-13 months). At the last follow-up, the ROM of DIPJ of the affected finger and the corresponding healthy finger were 43.28°±2.03° and 44.15°±1.12°, respectively, with no statistical significance ( t=1.32, P=0.084). TAM of the affected finger and the corresponding healthy finger were 240.15°±5.13° and 242.13°±3.11°, respectively, with no significant difference ( t=2.12, P=0.135). According to TAM system evaluation criteria, excellent in 27 cases, good in 3 cases, excellent and good rate was 100% (30/30). Conclusion:The combination of the minimally invasive percutaneous quantitative suture technique eight times and Kirschner wire elastic fixation has a satisfactory treatment outcome in the mallet finger, and there is no damage to the DIPJ surface. It is a simple, safe, effective method with minimal invasion.

Objective:To investigate the predictive value of inflammatory markers for the risk of stroke-associated infection (SAI) in patients with anterior circulation large vessel occlusive stroke who received endovascular therapy.Methods:Patients with anterior circulation large vessel occlusive stroke received endovascular treatment in Nanjing First Hospital, Nanjing Medical University from 2016 to 2020 were retrospectively enrolled. The clinical data of SAI group and non-SAI group were compared. Multivariate logistic regression analysis was used to screen the independent influencing factors of SAI, and then the predictive nomogram was established according to these influencing factors to verify its clinical application efficiency. Results:A total of 409 patients were enrolled during the study. Their age was 71.3±11.7 years, and 250 were male (61.1%). The median baseline Naitonal Institutes of Health Stroke Scale (NIHSS) score was 16. One hundred and nineteen patients (29.1%) received intravenous thrombolysis, 376 (91.9%) were successfully recanalized after endovascular therapy, and 293 (71.6%) developed SAI. Univariate analysis showed that age, atrial fibrillation ratio, NIHSS score at admission, fasting blood glucose, triglyceride, high sensitivity C reactive protein (hs-CRP), leukocyte count, neutrophil count, neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) were significantly higher than those in the non-SAI group (all P<0.05). Multivariate logistic regression analysis showed that age, NIHSS score at admission, fasting blood glucose, hs-CRP, leukocyte count, neutrophil count and NLR were the independent influencing factors of SAI ( P<0.05). Receiver operating characteristics curve analysis showed that the predictive value of multiple inflammatory markers (hs-CRP, leukocyte count, neutrophil count and NLR) for SAI was significantly better than that of the single inflammatory marker ( P<0.01). The area under the curve was 0.782 (95% confidence interval 0.719-0.846), and the predictive sensitivity and specificity were 80.6% and 64.5% respectively. Decision curve analysis showed that compared with the traditional indicators, the predictive nomogram based on inflammation related indicators (hs-CRP, leukocyte count and NLR) had a higher net profitability for predicting SAI. Conclusion:The hs-CRP, leukocyte count and NLR can be used to predict the risks of SAI in patients with acute ischemic stroke receiving endovascular therapy.

Objective:To investigate the predictive values of serum hypersensitive C-reactive protein (hs-CRP) and lipoprotein-associated phospholipase A 2 (Lp-PLA 2) for early neurological deterioration (END) and parenchymal hematoma (PH)-type 2 hemorrhagic transformation (HT) after intravenous thrombolysis in patients with acute ischemic stroke. Methods:Patients with acute ischemic stroke treated with intravenous thrombolysis in the Department of Neurology, Nanjing First Hospital, Nanjing Medical University from January 2018 to January 2021 were enrolled retrospectively. END was defined as an increase of ≥4 in the National Institutes of Health Stroke Scale (NIHSS) score at 24 h after thrombolysis compared with the baseline. PH-2 type HT was defined as parenchymal hematoma with obvious space occupying effect or hemorrhage at the distant site of infarct. Multivariate logistic regression analysis was used to determine the independent influencing factors of END and PH-2 type HT. The receiver operating characteristic (ROC) curve was used to evaluate the predictive value of hs-CRP and Lp-PLA 2 levels for END and PH-2 type HT. Results:A total of 804 patients with acute ischemic stroke treated with intravenous thrombolysis were included, of which 63 (7.8%) developed END within 24 h after intravenous thrombolysis; 41 (5.1%) developed HT, of which 38 were PH-2 type HT. Univariate analysis showed that the levels of serum hs-CRP and Lp-PLA 2 in the END group were significantly higher than those in the non-END group (all P<0.05), and the levels of serum hs-CRP and Lp-PLA 2 in the PH-2 HT group were significantly higher than those in the non-PH-2 HT group ( P<0.05). Multivariate logistic analysis showed that hs-CRP (odds ratio [ OR] 1.017, 95% confidence interval [ CI] 1.001-1.034; P=0.043) and Lp-PLA 2 ( OR 1.002, 95% CI 1.000-1.003; P=0.020) were the independent risk factors for END after intravenous thrombolysis. In addition, hs-CRP ( OR 1.019, 95% CI 1.002-1.036; P=0.027) and Lp-PLA 2 ( OR 1.002, 95% CI 1.000-1.003; P=0.018) were also the independent risk factors for PH-2 HT after intravenous thrombolysis. The ROC curve analysis showed that the areas under the curve of hs-CRP and Lp-PLA 2 for predicting END were 0.675 (95% CI 0.609-0.741; P<0.001) and 0.606 (95% CI 0.528-0.683; P=0.005) respectively, and the areas under the curve for predicting PH-2 HT were 0.641 (95% CI 0.545-0.737; P=0.003) and 0.600 (95% CI 0.500-0.699; P= 0.051) respectively. Conclusion:Higher baseline serum hs-CRP and Lp-PLA 2 are the independent predictors of END and PH-2 type HT after intravenous thrombolysis in patients with acute ischemic stroke.

Objective:To investigate the correlation between fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVHs) and outcomes after endovascular mechanical thrombectomy (EMT) in patients with anterior circulation large vessel occlusive stroke.Methods:Using " Nanjing First Hospital Stroke Database" , consecutive patients with anterior circulation large vessel occlusive stroke received EMT treatment from June 2015 to December 2018 were enrolled retrospectively. Before EMT treatment, the distal FVH grade and the American Society of Intervention and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) collateral circulation grade were evaluated. The modified Rankin Scale was used to evaluate the functional outcome of patients at 3 months after onset, and 0-2 was defined as a good outcome. Spearman correlation analysis was used to analyze the correlation between the distal FVH grade and the ASITN/SIR collateral circulation grade. Multivariate logistic regression analysis was used to identify the independent predictors of the outcomes. Results:A total of 117 patients with acute anterior circulation large vessel occlusive stroke were enrolled, aged 70.74±12.50 years, 72 (61.5%) were male. The baseline National Institutes of Health Stroke Scale (NIHSS) score was 13.73±4.91. Seventy-four patients (63.2%) had a good outcome and 43 (36.8%) had a poor outcome. The distal FVH grade was grade 0 in 8 cases (6.84%), grade 1 in 34 cases (29.06%), and grade 2 in 75 cases (64.10%). Compared with the distal FVH low-grade group (grade 0-1), the high-grade group (grade 2) had a higher ASITN/SIR collateral circulation grade ( P<0.001) and lower baseline National Institutes of Health Stroke Scale (NIHSS) score ( P=0.026). Spearman correlation analysis showed that the distal FVH grade was significantly positively correlated with the ASITN/SIR collateral circulation grade ( r=0.620, P<0.001). Multivariate logistic regression analysis showed that the high distal FVH grade (odds ratio [ OR] 0.336, 95% confidence interval [ CI] 0.128-0.879; P=0.026) was independently associated with the good outcomes, while the higher baseline NIHSS score ( OR 1.036, 95% CI 0.988-1.229; P=0.048) and symptomatic cerebral hemorrhage ( OR 5.597, 95% CI 1.052-29.761; P=0.043) were independently associated with the poor outcomes. Conclusion:The distal FVHs can reflect the state of collateral circulation. The high grade of distal FVHs is associated with the good outcomes after EMT in patients with anterior circulation large vessel occlusive stroke.