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 measure the air-absorbed dose rate of gamma radiation in public areas for the situation of the local radiation environment. Methods Using a large-volume γ spectrometer system with a NaI(Tl) detector mounted on a UAV, we conducted large-scale airborne radiation monitoring in public areas in southwestern China, to measure the air-absorbed dose rate at a height of 1 m from the earth’s surface. Results The airborne radiation monitoring data were used to analyze the local radiation environment. The mean air-absorbed dose rate at a height of 1 m was 43.6 ± 12.9 nGy/h. Seven abnormal radiation points were detected, and two of them were located where construction was ongoing. At one of the abnormal radiation points, FH40G meter measurements showed that the air-absorbed dose rate at a height of 1 m was up to 22.0 μGy/h. Field soil samples were collected for HPGe γ spectrometer analysis: the ²³²Th radionuclide activity concentration was 96.0 kBq/kg, and the ²²⁶Ra radionuclide activity concentration was 9.9 kBq/kg. Conclusion Using the UAV-mounted large-volume γ spectrometer system with NaI(Tl) detectors for large-scale airborne monitoring is a fast and effective method for dragnet monitoring of the level of radiation in public areas.

【Objective】 To explore the the potential risks of antiretroviral therapy(ART) drugs on blood safety among blood donors in Shenzhen. 【Methods】 High pressure liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) was used to measure ART drugs concentrations in the plasma of regular blood donors (negative control group, n=86) and anti-HIV positive individuals (experimental group, n=98, detected from approximately 440 000 blood donors during 2019—2023). The baseline plasma concentrations of ART drugs in the negative control group were clarified, and the impact of ART drugs on blood safety was analyzed. 【Results】 The baseline concentrations of ART drugs were not detected in 86 samples of negative control group. Four positive ART drugs samples were detected in 1∶2 pooled plasma samples of 98 anti-HIV positive blood donors plasma in the resolution test. The ART positive rate of anti-HIV positive donors was 4.08%, with tenofovir, lamivudine and efavirenz detected in three blood donors and lamivudine, lopinavir, ritonavir and zidovudine detected in one blood donor. 【Conclusion】 ART drugs were found among anti-HIV positive blood donors in Shenzhen. Additional research is needed to investigate the motivation of these specific donors, so as to ascertain the groups most susceptible to potential risks, and guarantee blood safety.

Objective To analyze the correlation between the expression of soluble glycoprotein A(GPA)in plasma of healthy blood donors and anti-M and anti-"Mia"antibodies.Methods Plasma from healthy donors from February 9,2022 to February 15,2023 was collected:irregular antibody-negative NN type(group Ⅰ,n=118)and MM type(group Ⅱ,n=51),anti-M antibody positive NN type(group Ⅲ,n=145)and anti-"Mia"antibody positive companion type(group Ⅳ,n= 87),the GPA content in plasma of different individuals in 4 groups was detected,and the difference in GPA expression was analyzed by t-test.Results The average plasma GPA contents in groupsⅠ,Ⅱ,Ⅲ and Ⅳ were 9.941±0.252,10.97±0.256,5.139±0.129 and 4.28±0.139ng/ml,respectively.The average GPA content of groups Ⅰ and Ⅱ was higher,and the average GPA content of groups Ⅲ and Ⅳ was lower,and the differences were statistically significant(all P＜0.01).Conclusion The GPA content in plasma of healthy donors with anti-M and anti-"Mia"antibodies was significantly lower than that of the antibody-negative group.The results of this study lay a foundation for further investigation of whether GPA in plasma has the ability to neutralize anti-M and anti-"Mia"antibodies,improve disease diagnosis and safe blood transfusion.

Background::Atopic dermatitis (AD) affects approximately 10% of adults worldwide. CM310 is a humanized monoclonal antibody targeting interleukin-4 receptor alpha that blocks interleukin-4 and interleukin-13 signaling. This trial aimed to evaluate the efficacy and safety of CM310 in Chinese adults with moderate-to-severe AD.Methods::This multicenter, randomized, double-blind, placebo-controlled, phase 2b trial was conducted in 21 medical institutions in China from February to November 2021. Totally 120 eligible patients were enrolled and randomized (1:1:1) to receive subcutaneous injections of 300 mg CM310, 150 mg CM310, or placebo every 2 weeks for 16 weeks, followed by an 8-week follow-up period. The primary endpoint was the proportion of patients achieving ≥75% improvement in the Eczema Area and Severity Index (EASI-75) score from baseline at week 16. Safety and pharmacodynamics were also studied.Results::At week 16, the proportion of EASI-75 responders from baseline was significantly higher in the CM310 groups (70% [28/40] for high-dose and 65% [26/40] for low-dose) than that in the placebo group (20%[8/40]). The differences in EASI-75 response rate were 50% (high vs. placebo, 95% CI 31%–69%) and 45% (low vs. placebo, 95% CI 26%–64%), with both P values <0.0001. CM310 at both doses also significantly improved the EASI score, Investigator’s Global Assessment score, daily peak pruritus Numerical Rating Scale, AD-affected body surface area, and Dermatology Life Quality Index compared with placebo. CM310 treatment reduced levels of thymus and activation-regulated chemokine, total immunoglobulin E, lactate dehydrogenase, and blood eosinophils. The incidence of treatment-emergent adverse events (TEAEs) was similar among all three groups, with the most common TEAEs reported being upper respiratory tract infection, atopic dermatitis, hyperlipidemia, and hyperuricemia. No severe adverse events were deemed to be attributed to CM310. Conclusion::CM310 at 150 mg and 300 mg every 2 weeks demonstrated significant efficacy and was well-tolerated in adults with moderate-to-severe AD.Trial Registration::ClinicalTrials.gov, NCT04805411.

Objective To investigate the application of intra pelvic pressure(IPP)in ultramicro-channel percutaneous nephrolithotripsy.Methods From January 2022 to January 2023,60 patients with urinary calculi who needed Super mini-PCNL(SMP)in The First Hospital of Jiaxing selected as the study objects.According to random number method,the patients were divided into control group and experimental group,with 30 cases.Both groups were treated with ultra-micro channel percutaneous nephrolithotripsia,while the experimental group was monitored and regulated IPP in real time during the operation,and observed and compared clinical indicators,IPP,fever,urinary protein,renal function,hemoglobin(Hb)and adverse reactions between the two groups.Results Compared with the control group,the hospitalization time of experimental group was shortened and the stone clearance rate was increased(P<0.05).The IPP levels of experimental groups at 6min,12min,24min and 36min were lower than those of control group(P<0.05).The fever of experimental group was lower than that of control group at 2d,3d,4d and 5d after operation(P<0.05).The urinary protein level of experimental group was lower than that of control group at 1d,2d,3d and 4d after operation(P<0.05).Compared with control group,blood urea nitrogen(BUN)and serum creatinine(SCr)levels of experimental group were decreased,and Hb levels were increased(P<0.05).The incidence of adverse reactions in experimental group was lower than that in control group(P<0.05).Conclusion Monitoring and adjusting intrapelvic pressure during super-mini percutaneous nephrolithotomy is beneficial in reducing postoperative fever in patients with urolithiasis,reducing urinary protein expression and kidney function damage,and controlling the occurrence of adverse reactions.It is worth recommending.

Objective:To investigate alterations in the glymphatic system of spinocerebellar ataxia type 3 (SCA3) patients based on quantitative MRI, and its association with genetic information and motor dysfunction.Methods:The study was a cross-sectional study. This prospective study recruited 39 confirmed SCA3 patients (SCA3 group) and 40 matched healthy controls (HC group) who were seen at the Southwest Hospital of Army Medical University from May 2017 to June 2023. All subjects underwent cranial MRI scanning. Clinical assessments were conducted on all participants using the scale for the assessment and rating of ataxia (SARA) and the international cooperative ataxia rating scale (ICARS). The automatic segmentation and volume measurement of the choroid plexus based on Freesurfer 6.0; the perivascular interstitial space (PVS) was automatically segmented based on the deep-learning model VB-Net, and the volume of the PVS in each brain region was quantified after manual correction. Independent samples t-test and Mann-Whitney U-test were used to analyze the changes in the class lymphatic system in the SCA3 group and the HC group. Pearson partial correlation analysis was used to explore the relationship between CAG repeats, the glymphatic system, and motor dysfunction. Results:The standardized choroid plexus volume in the SCA3 group was (1.24±0.36)×10 3 mm 3, and that in the HC group was (0.96±0.34)×10 3 mm 3, with a statistically significant difference ( t=4.01, P<0.001). PVS volumes in the frontal lobe, temporal lobe, parietal lobe, basal ganglia, cerebellum, thalamus, and brainstem regions in the SCA3 group were significantly higher than those of HC group ( P<0.05). Partial correlation analysis revealed that CAG repeats in SCA3 group were positively correlated with SARA, ICARS, and basal ganglia PVS volumes ( r=0.65, 0.58, 0.29; P=0.001, 0.001, 0.042). Cerebellar and temporal lobe PVS volumes were positively correlated with SARA ( r=0.59, 0.47; P=0.001, 0.003), and positively correlated with ICARS scores ( r=0.61, 0.40; P=0.001, 0.011). Choroid plexus volume was positively correlated with cerebellar and basal ganglia PVS volumes ( r=0.41, 0.31; P=0.009, 0.043). Conclusions:The glymphatic system of SCA3 patients have significant alteration and have association with CAG repeats and motor dysfunction.

Objective:To evaluate the influence of a moisturizer containing oat kernel oil for xeroderma and water content of the stratum corneum in children.Methods:From September to December 2022, 30 children with xeroderma were treated in the Dermatology Department of Tongzhou Maternal and Child Health Hospital of Beijing; 13 were males and 17 were females, and the age was 7.33±2.63 years. This was a single-center self-controlled trial. All children applied the moisturizer on the dry skin of the bilateral limbs two time per day for 14 days, and were followed up at 7 days and 14 days. Efficacy was evaluated according to the water content of the stratum corneum, visual scale, xerosis severity scale (XSS), Specified Symptom Sum Score (SRRC), Visual Analog Scale (VAS) and so on. and side-reactions were recorded.Results:After application of the moisturizer, the median of water content in the stratum corneum was 49.00 (33.83, 87.25), 48.84 (32.58, 100.34) at 7 d and 14 d respectively, showing significant increases compared with that at baseline (median 26.51 (16.00, 47.75) ( Z=-3.075, Z=-2.911, P<0.01). The visual scale, XSS, SRRC and VAS showed that compared with the baseline at 7 d, 14 d, the skin dryness and pruritus scores improved significantly ( Z=-4.424, -4.150, -3.943, -4.400; Z=-4.744, -4.409, -4.260, -4.409, P<0.01). Conclusions:The application of this moisturizer containing oat kernel oil could effectively improve skin dryness and the water content of the stratum corneum without serious adverse reactions.

Objective:To investigate the level change of serum total n-terminal propeptide of type Ⅰ precollagen (t-PINP) /type Ⅰ collagen carboxy-terminal peptide (beta-CTX) ratio, 25-hydroxyvitamin D (25-hydroxyvitamin D, 25 (OH) ) ratio, and 25-hydroxyvitamin D in elderly women with differentiated thyroid cancer (DTC) after surgery and its value in the prevention and treatment of osteoporosis (OP) .Methods:From Jan. 2020 to May. 2021, 112 elderly female postoperative DTC patients treated with thyroid stimulating hormone (TSH) suppression in Department of Endocrinology of Wenzhou Hospital of Integrative Medicine were collected for a prospective study, and the incidence of OP after 1 year of treatment was counted, and according to the incidence of OP, they were divided into incidence group ( n=78) and non-incidence group ( n=34). The general information, thyroid parameters [TSH, free triiodothyronine (FT3), free thyroxine (FT4) ], bone mineral density (BMD), and serum t-titrosine (BMD) were compared between the two groups. SPSS22.0 software was used, and the counting data was described by examples χ2 test. Grade data was expressed in u, Ridit test was used, measurement data was described in mean±standard deviation ( ±s), t test was used, Pearson correlation coefficient model was used to analyze postoperative thyroid index and serum t-PINP/β- Correlation between CTX ratio and 25 (OH) D level, and serum t-PINP after 1 year of treatment was analyzed through interaction/β- The role of CTX ratio and 25 (OH) D level in OP occurrence. Results:The incidence of OP after 1 year of TSH suppression treatment in 112 elderly female post-DTC patients in this study was 69.64% (78/112) ; serum TSH levels (0.63±0.19) mIU/ml after 1 year of treatment in patients who developed OP were lower than those in patients who did not develop OP (0.81±0.22) mIU/ml, and serum FT3 (6.15±1.71) pmol/ml and FT4 levels (24.63±4.28) pmol/ml were higher than those of patients without OP (4.32±1.29) pmol/ml and (20.36±3.70) pmol/ml ( t1=4.391, t2=5.581, t3=5.050,all P<0.05) .Serum t-PINP/β-CTX ratio (130.27±18.09) and 25 (OH) D level (20.18±4.15) ng/ml after 1 year of treatment in patients with OP were lower than those in patients without OP (148.56±20.37) and (23.36±4.36) ng/ml ( t1=4.733, t2=3.672, both P<0.05) ; serum TSH levels were positively correlated with serum t-PINP/β-CTX ratio and 25 (OH) D levels, and serum FT3 and FT4 levels were negatively correlated with serum t-PINP/β-CTX ratio and 25 (OH) D levels after 1 year of treatment in patients with OP ( P<0.05) ; low serum t-PINP/β-CTX ratio after 1 year of treatment expression, and low 25 (OH) D levels showed a positive interaction in OP occurrence in a superphase multiplicative model ( P<0.05) . Conclusion:Serum t-PINP/β-CTX ratio and 25 (OH) D level are closely associated with the occurrence of OP after DTC in elderly women, and postoperative monitoring can help prevent and treat OP.