[Determination of two perfluorinated compounds in urine by liquid chromatography-tandem mass spectrometry].

Objective: To establish a method for the determination of two perfluorinated compounds in urine by liquid chromatography-tandem mass spectrometry. Methods: In November 2022, urine samples were extracted by acidic methanol, purified by WAX solid phase extraction column, and eluted with methanol water, then Waters ACQUITY UPLC BEH C18 column (100 mm×2.1 mm, 1.7 µm) was used with 1.0 mmol/L ammonium acetate solution and methanol as mobile phase. The gradient elution was carried out, the detection was carried out by electrospray negative ion multiple response monitoring (MRM) mode, and the quantitative method was internal standard method. Results: Perfluorooctanoic acid and perfluorooctane sulfonic acid had a good linear relationship in the concentration range of 0.5-50.0 µg/L, and the correlation coefficient was >0.999. The limit of detection was 0.017 µg/L, and the limit of quantitation was 0.005 µg/L. The average recoveries were 96.3% and 101.8%, respectively. Days of precision were 3.5%-6.2% and 3.1%-7.4%, respectively, daytime precision were 4.3%-6.8% and 4.7%-8.1%, respectively. Conclusion: The established method of liquid chromatography-tandem mass spectrometry is high sensitivity and accuracy, and is suitable for the determination of perfluorooctanoic acid and perfluorooctane sulfonic acid in human urine.

[Diagnostic value of identifying location and amount of free gas in the abdominal cavity by multidetector computed tomography in patients with acute gastrointestinal perforation].

Objective: To evaluate the relationships between the location and extent of diffusion of free intraperitoneal air by multi-slice spiral CT (MSCT) and between the location and size of acute gastrointestinal perforation. Methods: This was a descriptive case series. We examined abdominal CT images of 33 patients who were treated for intraoperatively confirmed gastrointestinal perforation (excluding appendiceal perforation) in the Department of General Surgery, Nanfang Hospital between January and September 2022. We identified five locations of intraperitoneal air: the subphrenic space, hepatic portal space, mid-abdominal wall, mesenteric space, and pelvic cavity. We allocated the 33 patients to an upper gastrointestinal perforation (n=23) and lower gastrointestinal perforation group (n=10) base on intraoperative findings and analyzed the relationships between the locations of free gas and of gastrointestinal perforation. Additionally, we established two models for analyzing the extent of diffusion of free gas in the abdominal cavity and constructed receiver operating characteristic (ROC) curves to analyze the relationships between the two models and the size of the gastrointestinal perforation. Results: In the upper gastrointestinal perforation group, free gas was located around the hepatic portal area in 91.3% (21/23) of patients: this is a significantly greater proportion than that found in the lower gastrointestinal perforation group (5/10) (P=0.016). In contrast, free gas was located in the mesenteric interspace in 8/10 patients in the lower gastrointestinal perforation group; this is a significantly greater proportion than was found in the upper gastrointestinal perforation group (8.7%, 2/23) (P<0.010). The sensitivity of diagnosis of upper gastrointestinal perforation base on the presence of hepatic portal free gas was 84.8% and the specificity 71.4%. Further, the sensitivity of diagnosis of lower gastrointestinal perforation base on the presence of mesenteric interspace free gas was 80.0% and the specificity 91.3%. The rates of presence of free gas in the subdiaphragmatic area, mid-abdominal wall, and pelvic cavity did not differ significantly between the two groups (all P>0.05). Receiver operating characteristic curves showed that when free gas was present in four or more of the studied locations in the abdominal cavity, the optimal cutoff for perforation diameter was 2 cm, the corresponding sensitivity 66.7%, and the specificity 100%, suggesting that abdominal free gas diffuses extensively when the diameter of the perforation is >2 cm. Another model revealed that when free gas is present in three or more of the studied locations, the optimal cutoff for perforation diameter is 1 cm, corresponding to a sensitivity of 91.7% and specificity of 76.2%; suggesting that free gas is relatively confined in the abdominal cavity when the diameter of the perforation is <1 cm. Conclusion: Identifying which of five locations in the abdominal cavity contains free intraperitoneal air by examining MSCT images can be used to assist in the diagnosis of the location and size of acute gastrointestinal perforations.

[Determination of triclocarban and triclosan in urine by QuEChERS extraction and ultra-performance liquid chromatography-tandem mass spectrometry].

Objective: To establish a method for the determination of triclocarban (TCC) and triclosan (TCS) in urine by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) after purification by QuEChERS. Methods: In May 2022, urine samples were extracted by acetonitrile, purified by QuEChERS, separated by Waters Acquity UPLC BEH C18 column (100 mm×2.1 mm, 1.7 µm), and eluated with water-acetonitrile as mobile phase gradient at a flow rate of 0.3 ml/min. The detection was conducted in negative ion mode (ESI(-)) and multiple reaction monitoring (MRM) scanning, it was quantified with a internal standard method, and the methodology was verified. Results: The linear ranges of TCC and TCS were 0.5-100.0 µg/L and 1.0-100.0 µg/L, and the correlation coefficients were 0.9997 and 0.9991, respectively. The limits of detection and quantitation of TCC and TCS were 0.17 and 0.33 µg/L, and 0.5 and 1.0 µg/L, respectively. The recoveries of TCC and TCS were 100.1%-102.8% and 96.7%-108.6%, and the relative standard deviations were 4.9%-6.7% and 4.1%-8.3%, respectively, at 2.0, 10.0 and 80.0 µg/L. Conclusion: QuEChERS-UPLC-MS/MS method is simple, rapid, sensitive and reproducible, and can be used for rapid and accurate simultaneous detection of TCC and TCS exposure levels in occupational population.

[Application of intraoperative endoscopic in laparoscopic gastric cancer surgery].

The application of intraoperative endoscopic in laparoscopic gastric cancer surgery can compensate for the limitations of a single laparoscopic mode that only relies only on serous vision, and work as the Chinese saying "four ounces can move a thousand pounds". Intraoperative endoscopy not only effectively helps to accurately locate the tumor boundary in real-time and achieve precise resection, but also enables real time and interactive inspection of the quality of esophagojejunal anastomosis, reduces postoperative complications such as anastomotic leakage and bleeding, and accelerates postoperative recovery. However, most centers in China do not emphasize the application of intraoperative endoscopy in laparoscopic gastric cancer surgery due to the lack of a good cooperation mechanism between the gastrointestinal surgery team and the digestive endoscopy team. Therefore, based on clinical practice experience, the author briefly discusses the application of intraoperative endoscopic in routine laparoscopic gastric cancer surgery, including pre-examination preparation operator position, endoscopic techniques, postoperative management, etc., covering application scenarios such as early tumor localization, confirmation of upper esophageal margin confirmation, anastomotic examination, biopsy of primary lesion specimens in neoadjuvant/conversion treatment cases. We hope that it will help gastroenterologists to better apply intraoperative endoscopy in laparoscopic gastric cancer surgery, and assist in precise resection and safe anastomosis of the operation.

[Prediction of protection probability against Omicron BA.1, BA.4 and BA.5 variants in symptomatic infections with prototype strain based on neutralization antibody levels].

Objective: To predict the protection probability of different clinical outcomes after reinfection with Omicron variant in symptomatic and unvaccinated COVID-19 patients who infected with prototype strain. Methods: The data used in this study were derived from a systematic review and meta-analysis which systematically searched PubMed, Embase, Web of Science, and Europe PMC databases, included published and uploaded studies of dynamic changes of neutralizing antibodies in symptomatic COVID-19 patients from 1 January 2020 to 2 October 2022 and extracted the literature information, study design, serological experiment information and antibody results. According to the scatter distribution characteristics of antibody titer data, a generalized additive model based on Gaussian distribution was used to fit the titer value of neutralizing antibody based on logarithmic conversion and the dynamic change pattern of neutralizing antibody in symptomatic and unvaccinated COVID-19 patients infected with prototype strain over time was obtained. In this study, the fitted antibody titers of patients on the 28th, 51st, and 261st day after symptom onset was selected to predict the protection probability. Results: Neutralizing antibodies produced in symptomatic and unvaccinated patients infected with prototype strain could provide protection against Omicron reinfection, and the probability of protection gradually decreased with time. Neutralizing antibody level on day 28 after symptom onset provided protection probability of 30.3% (95%CI: 20.0%-45.5%) against reinfection, 51.5% (95%CI: 33.4%-75.9%) against symptomatic reinfection, and 91.2% (95%CI: 77.1%-97.7%) against severe reinfection caused by Omicron BA.5. The protection probability against Omicron BA.1, BA.4 and BA.5 reinfections decreased significantly 261 days after symptom onset, showing 9.6%-12.9%, 18.4%-23.9% and 63.1%-70.3% against three clinical outcomes, respectively. At the same time point and against the same clinical outcome, the protection probability of BA.1 was the highest, followed by BA.4 and BA.5. Conclusions: Neutralizing antibodies induced in symptomatic and unvaccinated COVID-19 patients previously infected with the prototype strain have limited protection probability against Omicron BA.5 reinfections and symptomatic reinfections. The protection probability against Omicron BA.5 reinfections is 30.3% 28 days after symptom onset and decreases to about 10% after 261 days. However, the protection probability against severe reinfections is considerable, with over 90% 28 days after symptom onset and still exceeding 60% after 261 days.

["Graded early warning system" of RET germline mutation carriers in MEN2A/MEN2B families and total thyroidectomy (report of 7 cases)].

Objective: To explore the reasonable time of prophylactic thyroidectomy for RET gene carriers in multiple endocrine neoplasia(MEN) 2A/2B families. Methods: From May 2015 to August 2021, RET gene carriers in MEN2A/MEN2B families were dynamically followed up at the Department of Thyroid Head and Neck Surgery, Beijing Tongren Hospital of Capital Medical University. The high-risk patients were encouraged to undergo prophylacitc total thyroidectomy according to the principle of "graded early warning system", namely the evaluation of gene detection, calcitonin value and ultrasound examination successively. Seven cases underwent the surgery, including 3 males and 4 females, aged from 7 to 29 years. According to the risk stratification listed in the guidelines of the American Thyroid Association in 2015, there were 2 cases of the highest risk, 2 cases of the high risk and 3 cases of the modest risk. Calcitonin index remained within the normal range in 3 cases and elevated in 4 cases before operation. All 7 patients underwent thyroidectomy with lymph node dissection of the level Ⅵ performed in 4 patients. Results: The time from suggestion to operation was 2 to 37 months, with an average of 15.1 months. The 6 patients were medullary thyroid carcinoma and 1 case with C-cell hyperplasia. The follow-up time was 2 to 82 months, with an average of 38.4 months. Postoperative serum calcitonin levels of all cases decreased to normal level, with biochemical cure. There was no sign of recurrence on ultrasound examination. All 7 patients had no serious complications, no obvious thyroid dysfunction. Their height, weight and other indicators of pediatric patients were similar to those of their peers, with normal growth and development. Conclusion: For healthy people with MEN2A/MEN2B family history, prophylactic thyroidectomy can be carried out selectively based on the comprehensive evaluation of "graded early warning system" with strict screening and close monitoring.

Intracranial plaque characteristics on high-resolution MRI and high-sensitivity C-reactive protein levels: association and clinical relevance in acute cerebral infarction.

AIM: To investigate the association between intracranial plaque characteristics and high-sensitivity C-reactive protein (hs-CRP) levels, and their combined effects on the occurrence of acute cerebral infarction (ACI). MATERIALS AND METHODS: One hundred and forty-three patients with recent ischaemic events in the territory of middle cerebral artery or basilar artery were enrolled and divided into the ACI group (n=93) and non-ACI group (n=50) according to clinical data and diffusion-weighting imaging (DWI) results. All recruited patients underwent high-resolution magnetic resonance imaging (MRI) to assess intracranial plaque characteristics, including plaque enhancement, standardised wall index, stenosis ratio, T1 hyperintense component, remodelling pattern, plaque area, plaque burden, and maximum wall thickness. hs-CRP levels were further grouped into the low group (<1 mg/l), the intermediate group (1-3 mg/l), and the high group (≥3 mg/l). Multivariate logistic regression and receiver operating characteristic curve were constructed to evaluate the association between intracranial plaque characteristics and hs-CRP levels, as well as their synergistic effects on determining the occurrence of ACI. RESULTS: High hs-CRP levels were associated with strong plaque enhancement (p<0.001, odds ratio [OR] = 7.497). Strong plaque enhancement (p=0.002, OR=2.109) and high hs-CRP levels (p=0.009, OR=3.893) were independently associated with the occurrence of ACI after adjustments for sex, age, and other traditional atherosclerotic risk factors. The combination of hs-CRP levels and strong plaque enhancement provided incremental information to determine ACI with an AUC of 0.823, which was significantly higher than that of strong plaque enhancement (0.711) and hs-CRP levels (0.686), respectively. CONCLUSION: High hs-CRP levels were associated with strong plaque enhancement. The synergistic effects of hs-CRP levels and strong plaque enhancement provided incremental effects on the occurrence of ACI.

Assessment of the degree of arterial stenosis in intracranial atherosclerosis using 3D high-resolution MRI: comparison with time-of-flight MRA, contrast-enhanced MRA, and DSA.

AIM: To compare the accuracy of three-dimensional (3D) high-resolution (HR) magnetic resonance imaging (MRI), time-of-flight magnetic resonance angiography (TOF-MRA), contrast-enhanced magnetic resonance angiography (CE-MRA), and digital subtraction angiography (DSA) in measuring the degree of stenosis in intracranial atherosclerosis. MATERIALS AND METHODS: All patients with intracranial artery ischaemic events underwent HR-MRI, TOF-MRA, and CE-MRA analysis, and some of these patients underwent DSA examination. The correlation between different methods for measuring the degree of lumen stenosis was analysed. The accuracy of HR-MRI, TOF-MRA, and CE-MRA was evaluated and compared with that of DSA. RESULTS: A total of 189 arterial stenoses were identified in 93 patients. Of these, 72 patients with 142 arterial stenoses underwent DSA examination. A very strong correlation between HR-MRI and CE-MRA measurements was shown (r=0.839, p<0.0001). The correlation between HR-MRI and TOF-MRA measurements was strong (r=0.720, p<0.0001). A very strong correlation between HR-MRI and DSA measurements was found (r=0.864, p<0.0001), and a similar correlation was observed between CE-MRA, and DSA measurements (r=0.843, p<0.0001). The correlation between TOF-MRA and DSA measurements was strong (r=0.686, p<0.0001). There was substantial agreement between HR-MRI and DSA measurements (K = 0.772) and between CE-MRA, and DSA measurements (K = 0.734) that was slightly higher than the agreement between TOF-MRA and DSA measurements (K = 0.636). CONCLUSION: HR-MRI can accurately measure stenosis (especially for moderate and severe stenosis) in intracranial atherosclerosis by direct visualisation of the vessel lumen and steno-occlusive plaque.

[SENP1 induced protein deSUMO modification increased the chemotherapy sensitivity of endometrial cancer side population cells].

Objective: To inhibit the stemness maintenance potential of endometrial cancer and increase the sensitivity of endometrial cancer side population cells to chemotherapy drugs by inducing extensive deSUMOylation modification of proteins. Methods: Flow cytometry was used to sort and culture CD133(+) CD44(+) KLE endometrial cancer cell clone spheres. Protein expression level of small ubiquitin-related modifier 1 (SUMO1) and two stemness maintenance genes of tumor side population cells, octamer binding transcription factor-4 (Oct4) and sex determining region Y-box2 (Sox2), were detected by western blotting method. Lentivirus-mediated Sentrin/SUMO-specific proteases 1 (SENP1) gene was stably transfected into KLE side population cells. Western blotting was used to detect the protein expressions of SENP1, SUMO1, Oct4 and Sox2. The clone formation rate was compared between KLE side population cells with or without SENP1 overexpression. Flow cytometry was applied to detect cell cycle changes. 3-(4, 5-Dimethylthiazole-2)-2, 5-diphenyl-tetrazolium bromide (MTT) experiment and flow cytometry apoptosis method were used to detect the chemosensitivity of the side population of endometrial cancer cells to cisplatin. Tumor-bearing mouse models of endometrial cancer were established to detect the effect of SENP1 overexpression on the chemotherapy sensitivity of cisplatin. Results: Compared with CD133(-)CD44(-) KLE cells, CD133(+) CD44(+) KLE side population cells could form clonal spheres and express higher levels of SUMO1, Oct4 and Sox2 proteins (P<0.05). Compared with KLE side population cells that were not transfected with SENP1 gene, the expression level of SENP1 protein in KLE side population cells overexpressing SUMO1、Oct4 and Sox2 were lower. The clonal sphere formation rate was reduced from (25.67±5.44)% to (7.46±1.42)%, and cell cycle shifted from G(0)/G(1) phase to G(2) phase. IC(50) of cisplatin decreased from (55.46±6.14) µg/ml to (11.55±3.12) µg/ml, and cell apoptosis rate increased from (9.76±2.09)% to (16.79±3.44)%. Overexpression of SENP1 could reduce the tumorigenesis rate of KLE side population cells in vivo and increase their chemotherapy sensitivity to cisplatin (P<0.05). Conclusion: Overexpression of SENP1 can induce protein deSUMOylation modification, inhibit the stemness maintenance potential of endometrial cancer side population cells, and enhance their chemotherapy sensitivity, which provides a new reference for gene therapy of endometrial cancer.

[The expression profile and potential regulatory mechanism of ACE2 in chronic rhinosinusitis with nasal polyps].

Objective: To preliminarily analyze the expression of angiotensin-converting enzyme 2 (ACE2) and to investigate its potential regulatory mechanism in chronic rhinosinusitis with nasal polyps (CRSwNP). Methods: Patients underwent nasal endoscopic surgery in the Third Affiliated Hospital of Sun Yat-sen University from February 2020 to May 2021 were selected, including 17 males and 6 females, aging from 23 to 66 years old. Expression of ACE2 was evaluated via immunohistochemical staining in controls with non-chronic rhinosinusitis, non-eosinophilic CRSwNP (non-ECRSwNP), and eosinophilic CRSwNP (ECRSwNP) tissue, respectively. Correlations between ACE2 and the indicated Th1/Th2-related cytokines (IFN-γ, IL-4, IL-5, IL-13, IL-25, IL-33, TSLP and periostin) were analyzed based on GSE72713 dataset. Protein-protein interaction (PPI) network was constructed via string database, immune infiltration of GSE72713 dataset was evaluated using cibersort algorithm. ACE2 was comprehensively analyzed by microRNA regulatory network, gene set enrichment analysis (GSEA) and pharmacological analysis. Statistical analysis was performed using GraphPad 7.0 and SPSS 20.0 software. Results: ACE2 was up-regulated in non-ECRSwNP compared with ECRSwNP. Microarray analysis showed that ACE2 was positively correlated with IFN-γ while inversely correlated with IL-5, IL-13 and periostin significantly. Analysis of immune infiltration suggested that ACE2 expression correlated positively with the number of M1 macrophage while negatively with M2 macrophage. GSEA demonstrated that interferon-related signaling pathways were up-regulated in non-ECRSwNP, and miRNA-200B/miRNA-200C/miRNA-429 pathways targeting ACE2 were enriched in ECRSwNP. Results of pharmacological analysis indicated that ampicillin was able to promote the expression of ACE2 whereas acetaminophen could down regulated the expression of ACE2. Conclusion: Expression pattern of ACE2 is varied in non-ECRSwNP and ECRSwNP, which may be related to the different infiltration of indicated cytokines and different regulatory pathways of miRNA.

[Safety and effectiveness of esophagojejunostomy through extracorporeal versus intracorporeal methods after laparoscopic total gastrectomy].

Objective: To compare the safety and effectiveness of esophagojejunostomy (EJS) through extracorporeal and intracorporeal methods after laparoscopic total gastrectomy (LTG). Methods: A retrospective cohort study was carried out. Clinicopathological data of 261 gastric cancer patients who underwent LTG, D2 lymphadenectomy, and Roux-en-Y EJS with complete postoperative 6-month follow-up data at the General Surgery Department of Nanfang Hospital from October 2018 to June 2021 were collected. Among these 261 patients, 139 underwent EJS with a circular stapler via mini-laparotomy (extracorporeal group), while 122 underwent intracorporeal EJS (intracorporeal group), including 43 with OrVil(TM) anastomosis (OrVil(TM) subgroup) and 79 with Overlap anastomosis (Overlap subgroup). Compared with the extracorporeal group, the intracorporeal group had higher body mass index, smaller tumor size, earlier T stage and M stage (all P<0.05). Compared with the Overlap subgroup, the Orvil(TM) subgroup had higher proportions of upper gastrointestinal obstruction and esophagus involvement, and more advanced T stage (all P<0.05). No other significant differences in the baseline data were found (all P>0.05). The primary outcome was complications at postoperative 6-month. The secondary outcomes were operative status, intraoperative complication and postoperative recovery. Continuous variables with a skewed distribution are expressed as the median (interquartile range), and were compared using Mann-Whitney U test. Categorical variables are expressed as the number and percentage and were compared with the Pearson chi-square, continuity correction or Fisher's exact test. Results: Compared with the extracorporeal group, the intracorporeal group had smaller incision [5.0 (1.0) cm vs. 8.0 (1.0) cm, Z=-10.931, P=0.001], lower rate of combined organ resection [0.8% (1/122) vs. 7.9% (11/139), χ(2)=7.454, P=0.006] and higher rate of R0 resection [94.3% (115/122) vs. 84.9 (118/139), χ(2)=5.957, P=0.015]. The morbidity of intraoperative complication in the extracorporeal group and intracorporeal group was 2.9% (4/139) and 4.1% (5/122), respectively (χ(2)=0.040, P=0.842). In terms of postoperative recovery, the extracorporeal group had shorter time to liquid diet [(5.1±2.4) days vs. (5.9±3.6) days, t=-2.268, P=0.024] and soft diet [(7.3±3.7) days vs. (8.8±6.5) days, t=-2.227, P=0.027], and shorter postoperative hospital stay [(10.5±5.1) days vs. (12.2±7.7) days, t=-2.108, P=0.036]. The morbidity of postoperative complication within 6 months in the extracorporeal group and intracorporeal group was 25.9% (36/139) and 31.1%, (38/122) respectively (P=0.348). Furthermore, there was also no significant difference in the morbidity of postoperative EJS complications [extracorporeal group vs. intracorporeal group: 5.0% (7/139) vs. 82.% (10/122), P=0.302]. The severity of postoperative complications between the two groups was not statistically significant (P=0.289). In the intracorporeal group, the Orvil(TM) subgroup had more estimated blood loss [100.0 (100.0) ml vs.50.0 (50.0) ml, Z=-2.992, P=0.003] and larger incision [6.0 (1.0) cm vs. 5.0 (1.0) cm, Z=-3.428, P=0.001] than the Overlap subgroup, seemed to have higher morbidity of intraoperative complication [7.0% (3/43) vs. 2.5% (2/79),P=0.480] and postoperative complications [37.2% (16/43) vs. 27.8% (22/79), P=0.286], and more severe classification of complication (P=0.289). Conclusions: The intracorporeal EJS after LTG has similar safety to extracorporeal EJS. As for intracorporeal EJS, the Overlap method is safer and has more potential advantages than Orvil(TM) method, and is worthy of further exploration and optimization.

Effect of Al substitution on the magnetization reversal and complex magnetic properties of NiCr2O4 ceramics.

A series of polycrystalline NiCr2-xAlxO4 (0.1 ≤ x ≤ 0.25) spinel ceramics have been synthesized using a sol-gel method. DC magnetization measurements are carried out at different temperatures and magnetic fields. A novel magnetization reversal has been observed in the field cooling process for the x = 0.2 sample, which can be ascribed to the competition between two magnetic sublattices due to their different temperature dependences. The magnetic interaction evolution, related to the complex magnetic properties, is revealed by exchange constants that have been estimated according to ferrimagnetic Curie-Weiss fitting and mean field theory. The fitting result confirmed the evolution of antiferromagnetic and ferromagnetic components with Al substitution, which is supported by the observations from the isothermal magnetization measurements. The positive and negative values of the magnetic moment can be utilized for storage applications based on the results of magnetic switching effect measurements.