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 investigate the short-term efficacy and safety of cardiac contractility modulation (CCM) in patients with heart failure.Methods:This was a cross-sectional study of patients with heart failure who underwent CCM placement at the First Affiliated Hospital of Xinjiang Medical University from February to June 2022. With a follow-up of 3 months, CCM sensation, impedance, percent output, and work time were monitored, and patients were compared with pre-and 3-month postoperative left ventricular ejection fraction (LVEF) values, and 6-minute walk test distance and New York Heart Association (NYHA) cardiac function classification, and the occurrence of complications was recorded.Results:CCM was successfully implanted in all 9 patients. Seven(7/9) of them were male, aged (56±14) years, 3 patients had ischaemic cardiomyopathy and 6 patients had dilated cardiomyopathy. At 3-month postoperative follow-up, threshold was stable, sense was significantly lower at follow-up than before (right ventricle: (16.3±7.0) mV vs. (8.2±1.1) mV, P<0.05; local sense: (15.7±4.9) mV vs. (6.7±2.5) mV, P<0.05), and impedance was significantly lower at follow-up than before (right ventricle (846±179) Ω vs. (470±65) Ω, P<0.05, local sense: (832±246) Ω vs. (464±63) Ω, P<0.05). The CCM output percentage was (86.9±10.7) %, the output amplitude was (6.7±0.4) V, and the daily operating time was (8.6±1.0) h. LVEF was elevated compared to preoperative ((29.4±5.2) % vs. (38.3±4.3) %, P<0.05), the 6-minute walk test was significantly longer than before ((96.8±66.7)m vs. (289.3±121.7)m, P<0.05). No significant increase in the number of NYHA Class Ⅲ-Ⅳ patients was seen (7/9 vs. 2/9, P>0.05). The patient was not re-hospitalised for worsening heart failure symptoms, had no malignant arrhythmic events and experienced significant relief of symptoms such as chest tightness and shortness of breath. No postoperative complications related to pocket hematoma, pocket infection and rupture, electrode detachment, valve function impairment, pericardial effusion, or cardiac perforation were found. Conclusions:CCM has better short-term safety and efficacy in patients with heart failure.

Objective:To evaluate the feasibility and safety of PT Scope (short for intelligent pressure and temperature controlled flexible ureteroscopy)combined with Thulium laser in the intracavitary treatment of upper urinary tract stones.Methods:A retrospective analysis was conducted on the clinical data of 13 patients with upper urinary tract stones who were treated with PT Scope combined with Thulium laser lithotripsy in Sun Yat-Sen Memorial Hospital from February to April 2024. There were 7 males and 6 females. The patients had a mean age of (46±10) years old, with an accumulated stone diameter of (25.8±13.3) mm. There were 7 cases of lower calyx stones (53.8%), and 3 cases of concomitant ureteral stones (23.1%).Four patients (30.8%) had positive preoperative urine cultures, and six patients (46.2%) had leukocyte counts greater than 100 cells/μl in their urine tests. The Thulium laser power was set at 45 W (1.5 J at 30 Hz, 0.3 J at 150 Hz). The renal pelvic pressure threshold was set at 30 mmHg (1 mmHg=0.133 kPa), and the temperature threshold at 43 ℃. Postoperatively, double J stents were placed for 2 to 4 weeks.Results:All 13 patients successfully completed the surgery. The median operative time was 30 (25, 90) minutes. The intraoperative average renal pelvic pressure in these 13 patients ranged from 8 mmHg to 24 mmHg, and the average renal pelvic temperature ranged from 25 ℃ to 34 ℃. Postoperatively, 1 patient experienced a fever (38.0 ℃) and 2 patients required analgesic treatment due to postoperative pain. There were no other intraoperative or postoperative complications. The median postoperative hospital stay was (1.5±0.8) days. The stone-free rate of 1 month was 84.6%(11/13).Conclusions:PT Scope combined with Thulium laser could effectively control renal pelvic pressure and temperature, achieve a high stone-free rate, and have a low complication rate. It is a safe and effective treatment for upper urinary tract stones.

Objective:To analyze the impact of post-dialysis blood pressure (Post-BP) on the long-term survival prognosis of maintenance hemodialysis (MHD) patients and the related risk factors.Methods:It was a retrospective cohort study. The data of patients who underwent their first hemodialysis (HD) from January 1, 2007, to June 30, 2021, as recorded in the dialysis registration system of the Kidney Disease Center, the First Affiliated Hospital, Zhejiang University School of Medicine was retrospectively analyzed. The mean Post-BP was calculated for each HD session 4-6 months after hemodialysis. According to the mean value of post-dialysis diastolic pressure (Post-DBP) at 4-6 months after dialysis, patients were divided into 3 groups (Post-DBP<80 mmHg, 80 mmHg≤Post-DBP<90 mmHg, Post-DBP≥90 mmHg). According to whether the mean value of post-dialysis systolic pressure (Post-SBP) was ≥140 mmHg and whether the mean value of Post-DBP was ≥80 mmHg, patients were divided into 4 groups (Post-SBP<140 mmHg, Post-DBP≥80 mmHg; Post-SBP≥140 mmHg, Post-DBP≥80 mmHg; Post-SBP<140 mmHg, Post-DBP<80 mmHg; Post-SBP≥140 mmHg, Post-DBP<80 mmHg). Patients' first dialysis time was used as the starting point of follow-up, and the end point of follow-up was death or conversion to peritoneal dialysis or kidney transplantation or up to December 31, 2021. Kaplan-Meier survival analysis, Log-rank test, and multivariate Cox regression model were used to analyze the relationship between Post-BP and survival rate and the related factors of prognosis in MHD patients.Results:According to inclusion criteria, a total of 1 213 patients were included. Kaplan-Meier survival curve showed that the long-term survival rate had statistically significant differences among Post-DBP<80 mmHg, 80 mmHg≤Post-DBP<90 mmHg and Post-DBP≥90 mmHg groups (Log-rank test, χ2=58.838, P<0.001), and Post-DBP<80 mmHg group was the lowest. Further comparing the cardiovascular diseases (CVD) mortality among the three groups, the curve showed a statistically significant difference (Log-rank test, χ2=27.926, P< 0.001), and the highest CVD mortality was found in the Post-DBP<80 mmHg group. Multivariate Cox regression model analysis showed that Post-DBP<80 mmHg was an independent associated factor for death in MHD patients (with Post-DBP mmHg≥90 group as reference, HR=4.197, 95% CI 1.452-12.197, P=0.008). When patients were divided into 4 groups according to whether the mean value of Post-SBP was ≥140 mmHg and whether the mean value of Post-DBP was ≥80 mmHg, Kaplan-Meier survival analysis showed a statistically significant difference in long-term survival rate among the four groups (Log-rank test, χ2=65.636, P<0.001), among which Post-SBP≥140 mmHg, Post-DBP<80 mmHg group had the lowest long-term survival rate. Further comparing the CVD mortality rate among the four groups, the curve showed a statistically significant difference (Log-rank test, χ2=29.784, P<0.001), and the highest CVD mortality rate was found in the Post-SBP≥140 mmHg, Post-DBP<80 mmHg group. Multivariate Cox regression analysis revealed that regardless of whether the average Post-SBP was ≥140 mmHg, Post-DBP<80 mmHg was an independent associated factor for death in MHD patients(with Post-SBP<140 mmHg, Post-DBP≥80 mmHg group as reference, Post-SBP≥140 mmHg, Post-DBP<80 mmHg group: HR=3.416, 95% CI 1.294-9.019, P=0.013; Post-SBP<140 mmHg, Post-DBP<80 mmHg group: HR=3.574, 95% CI 1.451-8.802, P=0.006). Conclusions:The long-term survival rate of the group with Post-SBP≥140 mmHg and Post-DBP<80 mmHg is significantly lower. Post-DBP<80 mmHg is an independent risk factor for death in MHD patients regardless of whether the average Post-SBP is ≥140 mmHg.

Objective:To conduct a scoping review of research on home-based palliative care for heart failure patients, explore its current development status, and provide a theoretical basis for future advancements in this field.Methods:A systematic search was performed in databases including CNKI, VIP, CBMdisc, Wanfang Data, PubMed, Web of Science, Embase, and Cochrane Library for literature related to home-based palliative care for heart failure patients. The search covered publications from the inception of each database until December 31, 2023. Literature was screened, and data were extracted, analyzed, and discussed.Results:A total of 19 studies were included, including randomized controlled trials, cohort studies, and qualitative research. The conceptual frameworks for home-based palliative care services for heart failure patients in these studies included the 6S model of palliative care, the 4C model of transitional care, the Omaha System, and chronic disease care models. The structure of these services was primarily nurse-led multidisciplinary team collaboration. Service forms included home visits and telephone follow-ups, with varying service frequencies. The content of the services included physical, psychological, social, and spiritual support. Outcome indicators mainly included patient readmission rates, quality of life, symptom burden, cost-effectiveness, and caregiver burden. Cohort study outcomes primarily focused on patient treatment preferences and place of death. Qualitative research explored the experiences of heart failure patients, caregivers, and healthcare providers with home-based palliative care.Conclusions:Home-based palliative care for heart failure patients has demonstrated positive effects in practice. It is recommended to standardize home-based palliative care models, clarify the needs of patients and their families, and identify barriers and facilitators to the development of home-based palliative care, thereby promoting its advancement for heart failure patients.

The silent lung that occurs during the perioperative period is characterized by rapid onset,rapid progression,and high mortality.This article reports a case of a 62-year-old patient with a left lower lung nodule who underwent lower lung segmentectomy under thoracoscopy and was assisted with tracheal intubation using rocuronium.21 minutes after the first administration,the patient presented with increased airway pressure,difficult ventilation,a"steel lung"feel,and symptoms similar to silent lung.Subsequently,80 mg of methylprednisolone and 50 μg of epinephrine(in divided doses)were injected intravenously,but no relief was observed,and the blood oxygen saturation decreased to 38％.In this case,after giving another 1 mg of epinephrine,the airway pressure gradually decreased to 33 cmH2O,and the blood oxygen saturation gradually increased.Considering that airway spasm might be caused by multiple intubation stimulations,additional rocuronium bromide was added to allow for reintubation.However,the patient again experienced increased airway pressure and difficulty in ventilation prior to intubation.The clinical pharmacist conducted a correlation evaluation of this adverse event and considered the result as possible.The mechanism,rescue and prevention of silent lung induced by rocuronium was also discussed in the case report.A thorough anesthesia assessment should be conducted prior to surgery,and an appropriate anesthesia induction plan should be formulated.Once an adverse event occurs,it should be promptly identified and treated.

Objective:To study the effect of blood volume feedback control system on improving intradialytic-hypotension (IDH) in maintenance hemodialysis (MHD) patients.Methods:It was a prospective cohort study. Thirty MHD patients with recurrent IDH in the Dialysis Center of the First Affiliated Hospital of Zhejiang University School of Medicine from March 2021 to March 2022 were selected. A self-control study was conducted in MHD patients. The patients were treated with routine hemodialysis in both baseline phase (A1) and reversal phase (A2), while with hemodialysis under the blood volume feedback control system in intervention phase (B). Each phase lasted for 4 weeks (12 hemodialysis sessions). The average occurrences of IDH and IDH-related adverse events (IDH-RAE, stopping dehydration for more than 10 minutes or getting off the hemodialysis machine 10 minutes earlier due to IDH) of each patient between phase A1, B, and A2 were calculated and compared. In a total of 1 080 dialysis records, a logistic regression analysis model was established with age, sex and intervention as independent variables and with the occurrence of IDH-RAE as the outcome.Results:A total of 30 eligible patients were included in the study, including 14 males (46.7%) and 16 females (53.3%), aged 63.0 (56.5, 72.5) years old, with a median dialysis age of 84.0 (37.2, 120.0) months. The average times of IDH in 30 MHD patients decreased from 1.17 (0.83, 1.67) in stage A1 (before intervention) to 0.33 (0.25, 0.58) in stage B (after intervention) ( P<0.05). The frequency of IDH-RAE decreased significantly from 0.29 (0.19, 0.47) in stage A1 to 0.17 (0,0.25) in stage B ( P<0.05). Logistic regression analysis results indicated that the use of blood volume feedback control system reduced the risk of IDH-RAE by 53% ( OR=0.47, 95% CI 0.34-0.64, P<0.001). Conclusions:The application of blood volume feedback control system can effectively reduce the occurrences of IDH and the risk of IDH-RAE in MHD patients.

Objective:To explore the clinical value of serum insulin combined with cardiac-related markers in evaluating the severity of sepsis associated encephalopathy (SAE).Methods:The clinical data of 130 children with sepsis who admitted to the Pediatric Intensive Care Unit of Hunan Children's Hospital from January 2018 to December 2021 were analyzed retrospectively, and the differences of serum insulin and cardiac-related markers in children with sepsis and SAE were compared.Results:The levels of serum insulin, creatine kinase isoenzyme, hypersensitive troponin T, and N-terminal cerebral urine peptide in the SAE group were significantly higher than those in the non-SAE group ( P<0.05), but there was no significant difference in heart rate and lactic acid ( P>0.05). The levels of serum insulin, creatine kinase isoenzyme, hypersensitive troponin T, N-terminal cerebral urine peptide and lactic acid in the death group were significantly higher than those in the survival group ( P<0.05), while the heart rate was not significantly different ( P>0.05). The area under ROC curve of serum insulin, creatine kinase isoenzyme, hypersensitive troponin T, and N-terminal cerebral urine peptide in predicting SAE were 0.841, 0.599, 0.700, and 0.667, respectively; in terms of judging the prognosis of sepsis, the area under ROC curve were 0.647, 0.669, 0.645, and 0.683, respectively; and in terms of judging the prognosis of children with SAE, the areas under the ROC curve were 0.509, 0.682, 0.666 and 0.555, respectively. Binary logistic regression equation was established with serum insulin, creatine kinase isoenzyme, hypersensitive troponin T, and N-terminal cerebral urine peptide: Y=8.153×NT-proBNP+1.704×CTnT-hs+27.121×insulin+0.946×CK-MB+1.573. The area under the ROC curve of the new variable Y in predicting sepsis SAE, evaluating the prognosis of sepsis, and predicting the prognosis of children with sepsis and SAE was 0.890, 0.756, and 0.729, respectively. Conclusions:Serum insulin, creatine kinase isoenzyme, hypersensitive troponin T, and N-terminal cerebral urine peptide can be used alone to determine the severity of sepsis and sepsis in children with SAE. The combined value of the four indicators is obviously better than that of the single indicator. The combined application of the four indicators may better evaluate the severity of sepsis and SAE.

Objective:To determine the impact of early serum sodium concentrations on the survival prognosis in maintenance hemodialysis (MHD) patients.Methods:It was a retrospective cohort study. The newly admitted hemodialysis patients who were included in the registration system of Zhejiang Province Dialysis Quality Control Center from January 1, 2010 to December 31, 2019 were identified. Follow-up was conducted until December 31, 2020. Baseline data were collected for the first three months of dialysis, in which the mean level of serum sodium was defined as early serum sodium. Patients were divided into five groups based on early serum sodium level. Restricted cubic spline (RCS) was used to fit the relationship between long-term serum sodium level and risk of death. Kaplan-Meier model and Log-rank test were used to compare the survival rates of different groups. Multivariable Cox regression was used to analyze the correlation between early serum sodium level and death.Results:A total of 26 309 MHD patients were included in this study, and their ages were (59.07±15.41) years (ranging from 18 to 100 years). Among them, 13 643 (51.9%) were over 60 years old and 15 843 (60.2%) were males. Among the primary diseases of chronic renal failure, chronic glomerulonephritis was the first [13 703 cases (52.1%)], followed by diabetic nephropathy [6 460 cases (24.6%)], hypertensive nephropathy [1 293 cases (4.9%)], polycystic kidney disease [1 164 cases (4.4%)], etc. According to early serum sodium level, 12 883 patients (49.0%) had hyponatremia (serum sodium <135 mmol/L), of which 4 001 patients (15.2%) had serum sodium ≤130 mmol/L; 1 529 patients (5.8%) had hypernatremia (serum sodium >145 mmol/L). Patients were divided into the following 5 groups: 4 001 cases (15.2%) in group 1 (serum sodium ≤130 mmol/L), 8 882 cases (33.8%) in group 2 (130 145 mmol/L). Among them, patients in the Na≤130 mmol/L group had a slightly older age, a higher proportion of diabetes and cardiovascular disease, a lower level of blood uric acid, albumin, hemoglobin, and a higher level of alkaline phosphatase and leukocytes, while patients in the Na >145 mmol/L group had an older age and a higher proportion of cardiovascular disease. After follow-up of (55.67±33.58) months, a total of 4 954 patients (18.8%) died, 1 537 patients (5.8%) underwent kidney transplantation, 128 patients (0.5%) were converted to peritoneal dialysis. Of the deaths, 990 (20.0%) were due to cardiovascular diseases, 498 (10.1%) to cerebrovascular diseases and 400 (8.1%) to infections, and cardiovascular disease was the main cause of death. RCS curve fitting of the relationship between serum sodium level and risk of death found that the all-cause mortality hazard ratio ( HR) increased with decreasing or increasing serum sodium, and the optimal serum sodium was between 135 mmol/L and 140 mmol/L. Kaplan-Meier survival curve showed that the risk of all-cause death (Log-rank test, χ2=66.5, P<0.001), the risk of cardiovascular death (Log-rank test, χ2=31.5, P<0.001) and the risk of infection death (Log-rank test, χ 2=28.6, P<0.001) were significantly different among five groups. The 10-year cumulative survival rate was 63.0%, 71.5%, 72.5%, 67.8% and 61.4% in groups with different serum sodium levels from low to high, and the 10-year cumulative cardiovascular mortality rate was 9.6%, 6.2%, 5.5%, 7.3% and 11.7%, and the 10-year cumulative infection mortality rate was 4.9%, 3.2%, 1.7%, 2.8% and 3.9%. Multivariable Cox regression showed early serum sodium level >145 mmol/L was an independent relevant factor for all-cause death in MHD patients ( HR=1.237, 95% CI 1.045-1.465, P=0.013). Conclusions:MDH patients are more likely to develop hyponatremia in the early stage of dialysis. The cumulative survival rate of all-cause death, cardiovascular death and infection death in patients with predialysis serum sodium ≤130 mmol/L and >145 mmol/L within three months after initiation of dialysis is significantly lower than those in other levels. Early serum sodium >145 mmol/L is associated with higher mortality in MHD patients.

BACKGROUND: The expression of programmed cell death ligand 1 (PD-L1) as a biomarker for immunotherapy in non-small cell lung cancer (NSCLC) is routinely detected in clinical pathology department. However, the spatial heterogeneity of PD-L1 expression in intrapulmonary tumors and extrapulmonary metastases is still a challenge for the clinical testing. This study aims to explore the differences of PD-L1 expression in test samples obtaining from different sites of NSCLC. This study may contribute to the detection strategy of PD-L1 in patients with advanced lung cancer. METHODS: One hundred and thirty-one cases of consecutively detected PD-L1 (22c3 assay, Dako) staining in metastatic NSCLC and 972 cases of non-paired intrapulmonary NSCLC were collected. The discrepancies of tumor proportion score (TPS) of PD-L1 expression in intrapulmonary samples and extrapulmonary metastatic samples of different sites were compared. RESULTS: The positive expression rate of PD-L1 in extrapulmonary metastatic NSCLC (TPS ≥ 1%) was 61.83%, and the TPS was significantly higher than that in intrapulmonary tumors (P=0.03). The PD-L1 scores of the specimens obtained from different sites were significantly different (P=0.007). The positive rates of PD-L1 in liver and adrenal metastases were 85.71% and 77.78% respectively, and their TPS were significantly higher than that of the intrapulmonary samples (P<0.05). The positive rates of PD-L1 in lymph node, bone, brain, soft tissue, and pleural metastases was 40.00%-66.67%, with no significant differences compared to intrapulmonary tumors. The analysis of histological subtype and sample type showed that the PD-L1 score of extrapulmonary samples of adenocarcinoma subtype or surgical specimen was significantly higher than that of intrapulmonary tumors. The analysis of clinicopathological parameters showed that the PD-L1 positive expression or high expression were significantly correlated with male patients, smoking history, and epidermal growth factor receptor (EGFR) wild type. CONCLUSIONS The expression of PD-L1 in metastatic NSCLC is generally higher than that in intrapulmonary tumor, and the positive rate of PD-L1 expression was discrepant in different sites of specimen. The differences of PD-L1 score between extrapulmonary metastatic samples and intrapulmonary samples may be associated with different metastatic sites, histological subtype, and specimen type.
B7-H1 Antigen/metabolism* ; Biomarkers, Tumor/metabolism* ; Carcinoma, Non-Small-Cell Lung/drug therapy* ; Humans ; Immunohistochemistry ; Lung Neoplasms/drug therapy* ; Male