Objective This study aims to achieve high-yield functional expression of the human voltage-gated potassium channel K_V3.1 using an Escherichia coli cell-free protein synthesis system, thereby providing a novel synthetic approach for drug screening, structural analysis and functional characterization of K_V3.1. Methods K_V3.1 was expressed in an Escherichia coli cell-free protein synthesis system for 10 hours in the presence of peptide surfactant A₆K. The secondary structure of K_V3.1 was analyzed by circular dichroism spectroscopy. The potassium channel activity of the recombinant protein liposome K_V3.1-A₆K was investigated using fluorescent dyes Oxonol VI as indicators, which are capable of reflecting alterations in membrane potential. Results Soluble K_V3.1 protein was successfully synthesized, achieving a purified yield of up to 1.2 mg/mL via an Escherichia coli cell-free protein synthesis system. Circular dichroism spectroscopy revealed that K_V3.1 exhibited characteristic α-helical secondary structures. Membrane potential fluorescence assays demonstrated that the K_V3.1-A₆K proteoliposomes, which were reconstructed with surfactant peptide A₆K, exhibited remarkable potassium ion permeability. Conclusion This study successfully achieved high-yield expression of human K_V3.1 with activity using an Escherichia coli-based cell-free protein synthesis system. This innovative method not only significantly enhances the expression yield of K_V3.1, but also maintains its functional activity, thereby establishing a novel and efficient synthetic platform for drug screening and advancing our understanding of structure-function relationships in K_V3.1 research.
Humans ; Escherichia coli/metabolism* ; Shaw Potassium Channels/biosynthesis* ; Cell-Free System ; Circular Dichroism ; Protein Biosynthesis ; Recombinant Proteins/metabolism* ; Membrane Potentials ; Shab Potassium Channels

Emerging evidences have indicated the role of ferroptosis in the progression of metabolic-associated fatty liver disease (MAFLD); thus, inhibiting ferroptosis is a promising strategy for the development of MAFLD therapeutics. Recent studies have demonstrated the antioxidative effect of the gut commensal bacterium Akkermansia muciniphila (A. muc); however, whether it can alleviate ferroptosis remains unclear. The current study indicates A. muc intervention efficiently reversed high-fat high-fructose diet (HFHFD)-induced lipid peroxidation and ferroptosis in the liver. These beneficial effects were mediated by activation of the hepatic AMPK/SIRT1/PGC-1α axis, as evidenced by the finding that AMPK deficiency abrogated the amelioration of lipid peroxidation in vitro and in vivo. Furthermore, the short-chain fatty acids (SCFAs) were enriched upon A. muc treatment, and acetate was identified as a key activator of hepatic AMPK signalling. Mechanistically, microbiota-derived acetate was transported to the liver and metabolized to adenosine monophosphate (AMP), which triggered AMPK activation. Furthermore, a colonization assay in germ-free mice confirmed that A. muc mediated antiferroptotic effects in the absence of other microbes. These data indicated that A. muc exerts antiferroptotic effects against MAFLD, at least partially by producing acetate, which activates the hepatic AMPK/SIRT1/PGC-1α axis to alleviate ferroptosis via the inhibition of polyunsaturated fatty acid (PUFA) synthesis.

Objective:To analyze the risk factors for central lymph node metastasis (CLNM) in patients with papillary thyroid cancer (PTC) aged 55 years and above, and to construct a predictive model with columnar graph.Methods:This retrospective study included 406 PTC patients aged 55 and above, treated at the First Affiliated Hospital of Zhengzhou University from Nov. 2019 to Feb. 2022. Data on demographic characteristics, disease features, and laboratory test results were collected. Univariate and multivariate logistic regression analyses were used to identify risk factors for CLNM and develop a clinical prediction model and nomogram.Results:The study involved 406 patients, divided into a modeling group (285 patients) and a validation group (121 patients). The predictive model identified independent risk factors for CLNM. In the modeling group, the model demonstrated a ROC AUC of 0.769, with 82.6% sensitivity, 63.0% specificity, and 67.7% accuracy. The validation group showed 66.7% sensitivity, 74.5% specificity, and 72.7% accuracy, with an AUC of 0.760. Hosmer-Lemeshow tests indicated good fit in both groups. Decision curve analysis confirmed the model's clinical decision-making value, showing better performance than traditional strategies and good generalizability and reliability.Conclusions:Sex, maximum tumor diameter, bilateral involvement of thyroid lobes, clinically evident cervical lymph nodes, and local invasion are independent predictive factors for CLNM in patients over 55 with papillary thyroid carcinoma (PTC). A clinical risk stratification nomogram model based on these risk factors demonstrates good predictive performance.

Objective To analyze the clinical characteristics of C-TI-RADS 3 thyroid nodules with a diameter greater than 2 cm and explore their correlation with gender,nodule ingredient,contralateral cancer presence,diffuse echo changes,TPOAB and TGAB.Methods A retrospective analysis was made on the clinical and pathological information of 94 patients with thyroid nodules who were admitted to our department from September 2022 to March 2023.All the patients underwent cytological and/or histopathological examinations.The proportions of TBS I category,benign tumors,low-risk tumors,and malignant tumors were calculated.The proportion of TBS type Ⅰ,benign tumors,low-risk tumors,and malignant tumors was quantified.Subsequently,a comparative analysis was conducted among the benign,low-risk,and malignant groups in terms of clinical characteristics including gender distribution,nodule composition,contralateral cancer occurrence,diffuse echo changes presence,as well as TPOAB and TGAB levels.Results Seven cases in TBS I category were excluded.Among the remaining 87 cases with confirmed pathology results for nodules,there were 72 benign cases(38 cytology cases and 34 histology cases),5 low-risk thyroid tumors(2 cytology cases and 3 histology cases),10 malignant cases(8 PTC cases,1 FTC case,and 1 MTC case).There was a significant difference in nodule ingredient(cystic/solid)between different pathological types(x2=10.369,P=0.006).However,no statistical significance was found in terms of gender,diffuse echo changes,contralateral cancer presence,TPOAB or TGAB(P＞0.05).Further analysis showed that the proportion of solid component was higher in low-risk tumors than in benign nodules(x2=9.571,P=0.002).No statistical significance was found between malignant nodules and low-risk nodules(x2=2.143,P=0.143),or between malignant nodules and benign nodules(x2=2.165,P=0.141).Conclusion Although TI-RADS 3 nodules are generally considered as potentially benign according to various versions of thyroid imaging reporting and data system,malignant nodules still account for a certain proportion.Attention should be paid to thyroid nodules with a typical ultrasonic signs,such as cystic nodules,thyroid follicular tumors and medullary thyroid carcinoma.Ultrasound guided fine needle aspiration cytopathology is necessary for evaluating benign and malignant nodules.It is necessary to pay attention to unsatisfactory or undiagnosable specimens to improve the accuracy of diagnosis.

Objective:To evaluate the effectiveness of hands-on training and video demonstration in training of forceps delivery for residents.Methods:Forty nine residents who were rotating in the obstetrics department of Peking Union Medical College Hospital from 2019 to 2021 were enrolled. The residents were randomly divided into two groups: the instructor group ( n=24) was taught by hands-on training of forceps delivery and the video group ( n=25) was instructed by watching video demonstration. All the trainees completed the self-confidence questionnaire survey, and were evaluated by written tests and objective structured assessment of technical skills scoring system. Results:The scores of self-confidence in each item after the simulation training were higher than those before training in both groups; and there were no significant differences between two groups in the increment of scores(mastering knowledge: 1.54±0.98 vs. 1.40±0.71, U=266.68, P=0.480;mastering operation skills: 1.42±0.93 vs.1.80±0.87, U=233.47, P=0.161; mastering forceps structure: 1.63±1.10 vs. 1.88±0.93, U=261.63, P=0.416; confidence in independent operation: 1.13±0.90 vs. 1.00±1.08, U=287.74, P=0.799; evaluation of simulation training: 0.21±0.51 vs. 0.16±0.55, U=288.27, P=0.776). In the written tests, the scores of the instructor group were significantly higher than those of the video group (83.00±7.18 vs.70.56±10.37; t=4.86, P<0.001). In the practical operation, the instructor group significantly outperformed the video group in items of “right blade placement” (0.71±0.46 vs. 0.20±0.41, U=147.54, P<0.001), “objective total score” (6.17±1.46 vs. 4.72±1.65, U=155.49, P=0.003) and “correct traction” (0.85±0.31 vs. 0.56±0.51, U=213.86, P=0.036). Conclusion:Training delivered via hands-on instruction and demonstration was generally more effective than that delivered via video, although both groups show a increased self-confidence in learning and performing forceps delivery.

【Objective】 To analyze the quality level of the laboratory pre-analytical phase, so as to take effective quality improvement interventions to further standardize the operation and provide basis for ensuring the quality of blood testing. 【Methods】 Pre-analytical phase quality indicators of blood screening laboratory in Shanghai Blood Center were established, and those had serious impact on blood safety were defined as the sentinel indicators. The pre-analytical quality level of our laboratory from 2018 to 2020 was statistically analyzed in terms of four parts including sample collection, preservation and submission, centrifugation and quality inspection, which contained 17 indicators. 【Results】 Eleven sentinel indicators were established, and the order of peak value from high to low in three years was as follows: " label omission" rated at 0.000 62% (2020), " label error" 0.000 57% (2018), " inappropriate storage of samples before detection" 0.007 39 (2018), " unqualified application form for sample detection" 0.007 39 (2018). The causes were analyzed and relevant measures were taken. Six monitoring indicators were established, and the order of peak value from high to low in three years was as follows: " insufficient sample" rated at 0.002 59% (year 2018), " hemolysis" 0.002 80% (year 2020), " pale color of blood supernatant (diluted)" 0.000 86 (2018), " automatic sampling interfered by blood clot" 0.027 02% (2018). 【Conclusion】 The quality indexes of pre-analytical phase in our laboratory have reached the level of domestic and international clinical laboratories. The establishment of pre-analytical quality indicators and sentinel indicators, with effective analysis and application, can fully record and monitor the quality of each link before laboratory testing, which is helpful to timely identify risks, detect deviations, and quickly implement corrective and preventive measures, thus further ensure the safety of clinical blood use.

Objective? To explore the effects of structured hypothermia intervention program in elderly intestinal cancer patients with frailty. Methods? From November 2017 to July 2018, we selected 96 patients with surgery for intestinal cancer scored more than two points in Fried frailty assessment for the aged before surgery at the First Affiliated Hospital of Hu'nan Normal University & People's Hospital of Hu'nan Province by cluster sampling. All of the patients were divided into experimental group (n=48) and control group (n=48) with the method of random number table. Experimental group carried out the structured management model, formulated and implemented the structured hypothermia intervention program, while control group provided warm nursing based on nursing routine. We compared the respiration, blood pressure, heart rate and blood oxygen saturation before, during and after surgery as well as temperature, incidence of hypothermia and related indicators (extubation time, retention time in resuscitation room, urine volume and intraoperative blood loss) at each time points during surgery. Results were analyzed with the repeated measure variance analysis, t test and χ2 test. Results? There were interactions between time and groups in temperature, blood pressure, heart rate, respiration and blood oxygen saturation (P＜ 0.05). The fluctuation with time of the above vital signs in the experimental group was lower than that of control group. In experimental group, the incidence of hypothermia was lower than that in control group; the extubation time and retention time in resuscitation room were shorter than those in control group; the intraoperative blood loss was less than that in control group and the urine volume was more than that in control group;the differences were all statistically significant (P＜ 0.01). Conclusions? The application of structured hypothermia intervention program in elderly intestinal cancer patients with frailty can effectively maintain the stable intraoperative vital signs, shorten the time anesthesia resuscitation, reduce the incidences of hypothermia and related complications, standardize preventive measures for intraoperative hypothermia and guarantee patient intraoperative safety among elderly intestinal cancer patients with frailty.

Hepatic cellular carcinoma is the third most common cause of cancer deaths in China.Partial hepatectomy is still the most effective treatment for hepatic cellular carcinoma.The liver is an organ with strong regenerative ability,and its regenerative mechanism is very complex.Majority of patients with hepatic cellular carcinoma are accompanied by cirrhosis,and cirrhosis is an important factor affecting the regeneration of the remaining liver after surgery.Liver regeneration is obviously impaired under this condition.However,the anti-liver fibrosis mechanisms behind these processes have not been completely elucidated,the current treatment of fibrosis is merely supportive care,and thus further definition of the antiliver fibrosis related factors such as keratinocyte growth factor,hepatocyte growth factor,milk fat globule epidermal growth factor 8,collagen-binding vascular endothelial growth factor,ex vivo expansion of circulating CD34+ cells has far-reaching significance for improving their prognosis.This article mainly introduces some relevant factors associated with anti liver fibrosis,for later use of single factor or a combination of multifarious factors to resist liver fibrosis,to provide reference for improving the ability of remained liver regeneration after partial hepatectomy.

Objective To clarify the role of BRAFV600E and TERT promoter mutations in cervical lymph node metastasis in papillary thyroid carcinoma.Methods The data of 432 patients with thyroid papillary carcinoma who underwent surgery from February 2017 to September 2017 at the First Affiliated Hospital of Zhengzhou University were analyzed retrospectively.The mutation of BRAFV600E and TERT promoter was detected by Sanger sequencing.The effect of BRAFV600E and TERT on cervical lymph node metastasis in patients with papillary thyroid carcinoma was analyzed by Chi-square test.Results The mutation rates of BRAFV600E and TERT promoter were 77.8％ (336/ 432) and 5.3％ (23/432) respectively in 432 papillary thyroid carcinoma patients.The probability of cervical lymph node metastasis in patients with BRAFV600E mutation was significantly higher than that in non-mutation patients (P ＜ 0.05).The probability of cervical lymph node metastasis in patients with TERT promoter mutation was significantly higher than that in non-mutated patients (P ＜ 0.05).Patients with both BRAFV600E and TERT promotermutation had a significantly higher incidence of cervical lymph node metastases than patients with the BRAFV600E mutation alone (P ＜ 0.05).Conclusions The mutations of BRAFV600E and TERT promoter are closely relevant to the occurrence of cervical lymph node metastasis in papillary thyroid carcinoma.Preoperative fine-needle aspiration cytology and postoperative routine pathological molecular diagnosis can help clinicians to develop a more rational treatment strategy,and a more accurate assessment of the risk of relapse.

OBJECTIVE:To investigate the perioperative prophylactic use of antibiotics in thoracic surgery department of 7 hos-pitals in Nantong city,and to provide reference for rational drug use in clinic. METHODS:In retrospective study,6652 dis-charged patients with thoracic surgery were selected from 7"third-level hospitals"of Nantong city during 2015-2016. The gender, age,length of stay,preoperative medication,medication timing,classification of incision,operation time,drug name,usage and dosage,route of administration,drug combination and prognosis were analyzed statistically. According to the relevant regulations of special rectification and the principle of perioperative antibiotics use,the rationality of antibiotics use was evaluated. RE-SULTS:Among 6652 patients,there were 2761 cases of typeⅠincision and 3891 cases of typeⅡincision. All of them used anti-biotics. Primary prophylactic time was 0.5-2 h before operation in 5282 cases,accounting for 79.40％;1370 cases were given medicine more than 2 h before surgery or after surgery,accounting for 20.60％. Totally 1070 cases received prophylactic medica-tion within 48 h,accounting for 16.09％;5582 cases received prophylactic medication more than 48 h,accounting for 83.91％. A total of 5702 cases were given only one antibiotic,and 950 cases received two-drug combination. A total of 6342 patients used an-tibiotics irrationally,accounting for 95.34％. Eight categories 15 kinds of antibiotics were involved. β-lactam/β-lactamase inhibi-tors,fluoroquinolones and cephalosporins were mostly used. CONCLUSIONS:After the implementation of special rectification, there are still many irrational phenomena in the prophylactic use of antibiotics in thoracic surgery department of 7 hospitals in Nan-tong city. Some indexes exceed the national standard and still need to be further managed and improved.