L-citrulline is a nonprotein amino acid that plays an important role in human health and has great market demand. Although microbial cell factories have been widely used for biosynthesis, there are still challenges such as genetic instability and low efficiency in the biosynthesis of L-citrulline. In this study, an efficient, plasmid-free, non-inducible L-citrulline-producing strain of Escherichia coli BL21(DE3) was engineered by combined strategies. Firstly, a chassis strain capable of synthesizing L-citrulline was constructed by block of L-citrulline degradation and removal of feedback inhibition, with the L-citrulline titer of 0.43 g/L. Secondly, a push-pull-restrain strategy was employed to enhance the L-citrulline biosynthesis, which realized the L-citrulline titer of 6.0 g/L. Thirdly, the NADPH synthesis and L-citrulline transport were strengthened to promote the synthesis efficiency, which achieved the L-citrulline titer of 11.6 g/L. Finally, fed-batch fermentation was performed with the engineered strain in a 3 L fermenter, in which the L-citrulline titer reached 44.9 g/L. This study lays the foundation for the industrial production of L-citrulline and provides insights for the modification of other amino acid metabolic networks.
Citrulline/biosynthesis* ; Escherichia coli/genetics* ; Metabolic Engineering/methods* ; Fermentation ; NADP/biosynthesis*

Objective:To evaluate the efficacy and safety of rituximab (RTX) in the treatment of idiopathic membranous nephropathy (IMN), explore the influencing factors of the therapeutic effect and construct a nomogram model for predicting the therapeutic effect.Methods:A single retrospective study was conducted in IMN patients in the First Affiliated Hospital of Zhejiang University School of Medicine from January 2017 to December 2022. All patients received monotherapy with RTX and were followed up for at least 12 months. RTX regimen adopted a B-cell guided regimen to achieve 0 cells/μl of peripheral blood CD19+ B cells through multiple administrations, followed by monitoring every 2?3 months and adding doses as needed to maintain this state. The complete response rate, partial response rate, and composite response rate at 6 months, 12 months and the end of follow up were analyzed. Logistic stepwise regression and R language were applied to construct a nomogram model for efficacy prediction. The receiver operating characteristic (ROC) curve, calibration curve and Hosmer-Lemeshow test were used to internally validate the nomogram model.Results:A total of 147 IMN patients were included in the study, with age of 56 (47, 65) years, 99 (67.4%) males. There were 69 (46.9%) newly treated patients, 78 (53.1%) retreatment patients. The follow-up time was 14.4 (12.0, 15.0) months. The total RTX dose was 1 800 (1 200, 2 400) mg. The composite response rates at 6 months, 12 months and the end of the follow-up were 36.7% (54/147), 59.9% (88/147) and 63.3% (93/147), respectively. The complete remission rates at 6 months, 12 months and the end of the follow-up were 6.1% (9/147), 13.6% (20/147) and 19.7% (29/147), respectively. Logistic stepwise regression analysis showed that age ≥ 65 years ( OR=0.335, 95% CI 0.135?0.833), retreatment ( OR=0.333, 95% CI 0.144?0.771), high cholesterol ( OR=0.716, 95% CI 0.577?0.888), high serum creatinine ( OR=0.978, 95% CI 0.963?0.993) and B-cell reconstruction within 6 months ( OR=0.273, 95% CI 0.115?0.645) were independent correlated factors affecting composite remission. Based on these factors, a nomogram model for predicting the therapeutic effect of RTX in IMN patients was constructed. The ROC curve indicated that the accuracy of this model in predicting composite remission was good ( AUC=0.814, 95% CI 0.744-0.883). The calibration curve showed that the predicted composite response rate had a good fit with the actual response rate (Hosmer-Lemeshow test χ2=11.917, P=0.155). Conclusions:RTX has good efficacy and safety as a monotherapy for IMN patients. The constructed nomogram prediction model has high discrimination and accuracy to predict the efficacy of RTX treatment for IMN.

Objective:To evaluate the efficacy and safety of rituximab (RTX) in the treatment of idiopathic membranous nephropathy (IMN), explore the influencing factors of the therapeutic effect and construct a nomogram model for predicting the therapeutic effect.Methods:A single retrospective study was conducted in IMN patients in the First Affiliated Hospital of Zhejiang University School of Medicine from January 2017 to December 2022. All patients received monotherapy with RTX and were followed up for at least 12 months. RTX regimen adopted a B-cell guided regimen to achieve 0 cells/μl of peripheral blood CD19+ B cells through multiple administrations, followed by monitoring every 2?3 months and adding doses as needed to maintain this state. The complete response rate, partial response rate, and composite response rate at 6 months, 12 months and the end of follow up were analyzed. Logistic stepwise regression and R language were applied to construct a nomogram model for efficacy prediction. The receiver operating characteristic (ROC) curve, calibration curve and Hosmer-Lemeshow test were used to internally validate the nomogram model.Results:A total of 147 IMN patients were included in the study, with age of 56 (47, 65) years, 99 (67.4%) males. There were 69 (46.9%) newly treated patients, 78 (53.1%) retreatment patients. The follow-up time was 14.4 (12.0, 15.0) months. The total RTX dose was 1 800 (1 200, 2 400) mg. The composite response rates at 6 months, 12 months and the end of the follow-up were 36.7% (54/147), 59.9% (88/147) and 63.3% (93/147), respectively. The complete remission rates at 6 months, 12 months and the end of the follow-up were 6.1% (9/147), 13.6% (20/147) and 19.7% (29/147), respectively. Logistic stepwise regression analysis showed that age ≥ 65 years ( OR=0.335, 95% CI 0.135?0.833), retreatment ( OR=0.333, 95% CI 0.144?0.771), high cholesterol ( OR=0.716, 95% CI 0.577?0.888), high serum creatinine ( OR=0.978, 95% CI 0.963?0.993) and B-cell reconstruction within 6 months ( OR=0.273, 95% CI 0.115?0.645) were independent correlated factors affecting composite remission. Based on these factors, a nomogram model for predicting the therapeutic effect of RTX in IMN patients was constructed. The ROC curve indicated that the accuracy of this model in predicting composite remission was good ( AUC=0.814, 95% CI 0.744-0.883). The calibration curve showed that the predicted composite response rate had a good fit with the actual response rate (Hosmer-Lemeshow test χ2=11.917, P=0.155). Conclusions:RTX has good efficacy and safety as a monotherapy for IMN patients. The constructed nomogram prediction model has high discrimination and accuracy to predict the efficacy of RTX treatment for IMN.

The pathological classification and diagnostic criteria for lung neuroendocrine neoplasms (NENs) in the 2021 World Health Organization (WHO) lung tumor classification are similar to the prior classifications. However, the advances on the molecular studies of lung NENs have shown that both small cell lung carcinoma and large cell neuroendocrine carcinoma are highly heterogeneous tumors with neuroendocrine characteristics and can be subclassified based on the features of genomics or transcriptomics, which are valuable in the diagnosis of lung NENs subtypes and patient treatment. In addition, it is necessary to interpret emerging concepts such as "lung neuroendocrine tumor G3" and "histological transformation" from pathological perspectives, as well as to know the novel neuroendocrine biomarkers such as INSM1 and POU2F3. This article summarized the diagnostic changes and the advances of molecular pathology of lung NENs based on the latest WHO classification and molecular research.

The paper reports a rare case of idiopathic multicentric Castleman's disease with nephrotic syndrome as the first presentation. The patient was a 68-year-old male, presented with edema at admission. His clinical manifestations included nephrotic syndrome, and multiple enlarged lymph nodes. Renal biopsy showed minimal change disease, and cervical lymph node biopsy showed Castleman's disease. The patient received treatment of glucocorticoid combined with tocilizumab, and then rituximab. After 14 months of follow-up, the patient achieved remission of nephrotic syndrome.

This article reports the diagnosis and treatment of a case of acromegaly in a pregnant patient who took bromocriptine during pregnancy and delivered successfully. A retrospective summary of the clinical data and treatment outcomes before and after two pregnancies of the patient is provided. The patient took bromocriptine during the second pregnancy, and her condition remained stable. A baby girl was delivered by caesarean section at full term. The article suggests that pregnancy in acromegaly patients, after the stabilization of the condition, can lead to favorable outcomes. The use of dopamine receptor agonists during pregnancy does not increase adverse events during the perinatal period.

Objective To establish a personalized Stanford type B aortic dissection numerical simulation model, and using computational fluid dynamics (CFD) numerical simulation to obtain the hemodynamic behavior and law of the type B aortic dissection at different stages of development. Methods Based on the theory of three-dimensional model reconstruction, we used CT images of a patient with type B aortic dissection in the Xiamen Cardiovascular Hospital of Xiamen University, relevant medical image processing software to reconstruct a personalized aortic three-dimensional model, and CFD to reconstruct the model which was simulated in fluid mechanics. Results The three-dimensional reconstruction model could intuitively observe the changing trend of the false cavity at different stages of the dissection development. Through fluid mechanics simulation, the blood flow rate, pressure, wall shear stress, vascular wall Von Mises stress and other parameters at different stages of the dissection development were obtained. Conclusion The hemodynamic behavior and law of relevant parameters in the development stage of aortic dissection are analyzed. The combination of the values of relevant parameters and clinical medical detection and diagnosis can well predict the development of the disease, and finally provide more theories and methods for the scientific diagnosis of aortic dissection.

OBJECTIVE: To investigate the effectiveness of arthroscopic multi-point fixation with anchor and suture in the treatment of tibial insertion avulsion fracture of anterior cruciate ligament (ACL) involving the anterior root of lateral meniscus (LM). METHODS: A retrospective analysis was conducted on the clinical data of 28 patients with tibial insertion avulsion fracture of ACL involving the anterior root of LM who were treated with arthroscopic multi-point fixation with anchor and suture between October 2017 and January 2023. There were 12 males and 16 females with the mean age of 26 years (range, 13-57 years). There were 20 cases of sports injury and 8 cases of traffic accident injury. In 2 cases of old fracture, the time from injury to operation was 45 days and 90 days, respectively; in 26 cases of fresh fracture, the time from injury to operation was 3-20 days (mean, 6.7 days). According to the Meyers-McKeever classification, there were 4 cases of type Ⅱ, 11 cases of type Ⅲ, and 13 cases of type Ⅳ. The preoperative Lysholm knee function score was 42.1±9.0, the International Knee Documentation Committee (IKDC) score was 40.0±7.3, and the Tegner score was 0.7±0.7. RESULTS: All operations were successfully completed, and the incisions healed by first intention. All the 28 patients were followed up 5-60 months (mean, 20.4 months). During the follow-up, there was nocomplication such as infection, vascular or nerve injury, loosening or breakage of internal fixator, or stiffness of knee joint. Postoperative X-ray films showed satisfactory fracture reduction and firm fixation. All fractures healed clinically, and the healing time was 8-16 weeks (mean, 10.3 weeks). At last follow-up, Lachman test and anterior drawer test were negative. At last follow-up, Lysholm knee function score was 92.4±5.5, IKDC score was 91.6±4.4, and Tegner score was 5.2±1.1, which significantly improved when compared with preoperative scores ( t=-22.899, P<0.001; t=-29.870, P<0.001; t=-19.979, P<0.001). CONCLUSION Multi-point fixation with anchor and suture in the treatment of tibial insertion avulsion fracture of ACL involving the anterior root of LM can not only fix the LM, but also effectively reduce and fix the avulsion fracture, which can obtain good effectiveness.
Male ; Female ; Humans ; Adult ; Anterior Cruciate Ligament/surgery* ; Menisci, Tibial/surgery* ; Fractures, Avulsion/surgery* ; Retrospective Studies ; Anterior Cruciate Ligament Injuries/surgery* ; Treatment Outcome ; Arthroscopy ; Tibial Fractures/surgery* ; Knee Joint/surgery* ; Sutures ; Suture Techniques

OBJECTIVE: To investigate the repair method of type Ⅱc injury in the lateral meniscus popliteal tendon area based on the porcine knee joint. METHODS: Eighteen commercially available fresh porcine knee joints were randomly divided into 3 groups ( n=6). After preparing a type Ⅱc injury in the lateral meniscus popliteal tendon area, and the anterior (group A), posterior (group B), or anterior and posterior (group C) of the popliteal hiatus (PH) was sutured by vertical mattress. The tension meter was used to apply gradient tensions of 2, 4, 6, 8, and 10 N along the tibial plateau horizontally, respectively, to pull the midpoint of the lateral meniscus popliteal tendon area. The displacement values before modeling, after modeling, and after suture were recorded. The reduction value of lateral meniscus displacement and reduction rate after suture were calculated and compared between groups. RESULTS: There was no significant difference between groups ( P>0.05) in the displacement values before modeling, after modeling, and after suture under different tensions. There was no significant difference between groups A and C ( P>0.05) in the reduction value of lateral meniscus displacement and reduction rate after suture under different tensions. The reduction value of lateral meniscus displacement and reduction rate after suture in group B were lower than those in groups A and C. The reduction value of lateral meniscus displacement under tension of 2 N and the reduction rates under tensions of 2, 4, and 6 N between groups A and B showed significant differences ( P<0.05). The reduction value of lateral meniscus displacement and the reduction rate under tensions of 2, 4, and 6 N between groups B and C showed significant differences ( P<0.05). CONCLUSION Suturing the anterior area of PH is the key to repairing type Ⅱc injury of lateral meniscus popliteal tendon area.
Animals ; Humans ; Knee ; Knee Joint ; Menisci, Tibial/surgery* ; Swine ; Tendons ; Tibia