An electrochemical chemical oxygen demand(COD)sensor was proposed based on a FTO/TiO2/PbO2 electrode and a thin-layer electrochemical cell.The FTO/TiO2/PbO2 electrode was characterized by X-ray photoelectronic spectroscopy(XPS),X-ray diffraction(XRD)spectroscopy and electrochemical technique,and the results indicated that the rapid decrease in the output signals of the electrochemical COD sensor could be attributed to oxidation of PbSO4 occurring on the surface of FTO/TiO2/PbO2 electrode.The PbO2 deposition time and concentration of Na2SO4 were further optimized and then the electrochemical COD sensor was challenged by real samples including laker water sample,river water sample and wastewater sample.The evolution trend of signals of the electrochemical COD sensor in response to lake and river water samples was identical with that obtained with the standard method(HJ/T399-2007,Water quality-determination of the chemical oxygen demand-fast digestion-spectrophotometric method).The electrochemical COD sensor exhibited significant increase in the signal intensity after the samples were switched from lake water to wastewater sample,and a mean value of 32.5 mg/L with relative standard deviation(RSD)of 6.8%were obtained after measuring 45 times the wastewater with COD value of 30 mg/L under a sampling interval of 400 s.The as-prepared electrochemical COD sensor possessed good promise in regular monitoring of COD,discharge of wastewater and industrial process control,with advantages such as a small sampling interval,mild reaction conditions and no requirement of toxic and harmful chemical reagents.

Objective:To investigate the therapeutic effect of exosomes derived from remote ischemic conditioning on neurological dysfunction after cardiopulmonary resuscitation in a rat model of cardiac arrest and the relationship with glycocalyx protection.Methods:Exosomes were isolated from the blood of healthy adult male Sprague-Dawley rats using ultracentrifugation after undergoing remote ischemic conditioning for use as intervention drugs. Nanoparticle tracking analysis technology was used for exosome detection. Thirty-six adult male Sprague-Dawley rats were randomly assigned to 3 groups ( n=12 each) :Sham group, Control group and Exosome group. Cardiac arrest was induced by asphyxia for 7 min in the Control and Exosome groups. Placebo or exosomes (1×10 10 Particles) were infused intravenously at 5 min after the rats had returned of spontaneous circulation. Neuropsychological deficit score (NDS), open field test, Y maze and Morris water maze were used to assess neurological outcomes. The levels of plasma Hyaluronic acid (HA) and syndecan-1 (Sdc-1) were detected by Elisa. The expression levels of matrix metalloproteinase-2/9 (MMP-2/9) in hippocampal CA1 region were detected by Western blot. Results:After undergoing remote ischemic conditioning, the plasma levels of exosomes were elevated in rats compared to normal rats. Compared with the control group, the behavioral experiment of rats in the exosomes group were significantly improved, as evidenced by an increase in horizontal locomotor distance (5.86±2.89 vs. 17.53±5.51, P< 0.05), an increase in the correct rate of spontaneous alternation (13.29±15.07 vs. 42.63±10.25, P< 0.05), and a shortening of avoidance latency (25.83±8.54 vs. 13.49±4.55, P< 0.05). Plasma HA and Sdc-1 levels were significantly lower 24 h after resuscitation (HA: 26.34±9.83 vs. 14.84±6.26, P< 0.05; Sdc-1: 0.05±0.03 vs. 0.02±0.02, P<0.05), along with significantly lower MMP-2/9 levels in hippocampal tissue. Conclusions:Exosomes extracted from the plasma of rats undergoing remote ischemic conditioning can improve neurological dysfunction after cardiac arrest in rats, and the mechanism may be related to the inhibition of metalloproteinases and the reduction of endothelial glycocalyx degradation.

To investigate the effect and the mechanism of ppk1 gene deletion on the drug susceptibility of uropathogenic Escherichia coli producing extended-spectrum beta-lactamases (ESBLs-UPEC). The study was an experimental study. From March to April 2021, a strain of ESBLs-UPEC (genotype was TEM combined with CTX-M-14) named as UE210113, was isolated from urine sample of the patient with urinary tract infection in the Laboratory Department of Guangzhou Eighth People's Hospital, meanwhile its ppk1 gene knock-out strain Δpk1 and complemented strain Δpk1-C were constructed by suicide plasmid homologous recombination technique, which was used to study the effect of ppk1 gene on ESBLs-UPEC drug sensitivity and its mechanism. The drug susceptibility of UE210113, Δpk1, and Δpk1-C were measured by Vitek2 Compact System and broth microdilution method. The quantitative expression of ESBLs, outer membrane protein and multidrug efflux systems encoding genes of UE210113, Δpk1 and Δpk1-C were performed by using qRT-PCR analysis. By using two independent sample Mann-Whitney U test, the drug susceptibility results showed that, compared with UE210113 strain, the sensitivities of Δpk1 to ceftazidime, cefepime, tobramycin, minocycline and cotrimoxazole were enhanced (Z=-2.121,P<0.05;Z=-2.236,P<0.05;Z=-2.236,P<0.05;Z=-2.121,P<0.05), and the drug susceptibility of Δpk1-C restored to the same as which of UE210113 (Z=0,P>0.05). The expression levels of ESBLs-enconding genes bla_TEM and bla_CTX-M-14 in Δpk1 were significantly down-regulated compared with UE210113, but the expression was not restored in Δpk1-C. The expression of outer membrane protein gene omp F in Δpk1 was significantly up-regulated, while the expression of omp A and omp C were down-regulated. The results showed that the expression of multidrug efflux systems encoding genes tol C, mdt A and mdtG were down-regulated in Δpk1 compared with UE210113. The expression of all of the outer membrane protein genes and the multidrug efflux systems genes were restored in Δpk1-C. In conclusion,the lost of ppk1 gene can affect the expression of the outer membrane protein and multidrug efflux systems encoding genes of ESBLs-UPEC, which increase the sensitivity of ESBLs-UPEC to various drugs.
Humans ; beta-Lactamases/metabolism* ; Uropathogenic Escherichia coli/metabolism* ; Urinary Tract Infections ; Plasmids ; Membrane Proteins/genetics* ; Escherichia coli Infections ; Microbial Sensitivity Tests ; Anti-Bacterial Agents/pharmacology*

To investigate the effect and the mechanism of ppk1 gene deletion on the drug susceptibility of uropathogenic Escherichia coli producing extended-spectrum beta-lactamases (ESBLs-UPEC). The study was an experimental study. From March to April 2021, a strain of ESBLs-UPEC (genotype was TEM combined with CTX-M-14) named as UE210113, was isolated from urine sample of the patient with urinary tract infection in the Laboratory Department of Guangzhou Eighth People's Hospital, meanwhile its ppk1 gene knock-out strain Δpk1 and complemented strain Δpk1-C were constructed by suicide plasmid homologous recombination technique, which was used to study the effect of ppk1 gene on ESBLs-UPEC drug sensitivity and its mechanism. The drug susceptibility of UE210113, Δpk1, and Δpk1-C were measured by Vitek2 Compact System and broth microdilution method. The quantitative expression of ESBLs, outer membrane protein and multidrug efflux systems encoding genes of UE210113, Δpk1 and Δpk1-C were performed by using qRT-PCR analysis. By using two independent sample Mann-Whitney U test, the drug susceptibility results showed that, compared with UE210113 strain, the sensitivities of Δpk1 to ceftazidime, cefepime, tobramycin, minocycline and cotrimoxazole were enhanced (Z=-2.121,P<0.05;Z=-2.236,P<0.05;Z=-2.236,P<0.05;Z=-2.121,P<0.05), and the drug susceptibility of Δpk1-C restored to the same as which of UE210113 (Z=0,P>0.05). The expression levels of ESBLs-enconding genes bla_TEM and bla_CTX-M-14 in Δpk1 were significantly down-regulated compared with UE210113, but the expression was not restored in Δpk1-C. The expression of outer membrane protein gene omp F in Δpk1 was significantly up-regulated, while the expression of omp A and omp C were down-regulated. The results showed that the expression of multidrug efflux systems encoding genes tol C, mdt A and mdtG were down-regulated in Δpk1 compared with UE210113. The expression of all of the outer membrane protein genes and the multidrug efflux systems genes were restored in Δpk1-C. In conclusion,the lost of ppk1 gene can affect the expression of the outer membrane protein and multidrug efflux systems encoding genes of ESBLs-UPEC, which increase the sensitivity of ESBLs-UPEC to various drugs.
Humans ; beta-Lactamases/metabolism* ; Uropathogenic Escherichia coli/metabolism* ; Urinary Tract Infections ; Plasmids ; Membrane Proteins/genetics* ; Escherichia coli Infections ; Microbial Sensitivity Tests ; Anti-Bacterial Agents/pharmacology*

Objective: To establish a predictive model for survival benefit of patients with intrahepatic cholangiocarcinoma (ICC) who received adjuvant chemotherapy after radical resection. Methods: The clinical and pathological data of 249 patients with ICC who underwent radical resection and adjuvant chemotherapy at 8 hospitals in China from January 2010 to December 2018 were retrospectively collected. There were 121 males and 128 females,with 88 cases>60 years old and 161 cases≤60 years old. Feature selection was performed by univariate and multivariate Cox regression analysis. Overall survival time and survival status were used as outcome indicators,then target clinical features were selected. Patients were stratified into high-risk group and low-risk group,survival differences between the two groups were analyzed. Using the selected clinical features, the traditional CoxPH model and deep learning DeepSurv survival prediction model were constructed, and the performance of the models were evaluated according to concordance index(C-index). Results: Portal vein invasion, carcinoembryonic antigen>5 μg/L,abnormal lymphocyte count, low grade tumor pathological differentiation and positive lymph nodes>0 were independent adverse prognostic factors for overall survival in 249 patients with adjuvant chemotherapy after radical resection (all P<0.05). The survival benefit of adjuvant chemotherapy in the high-risk group was significantly lower than that in the low-risk group (P<0.05). Using the above five features, the traditional CoxPH model and the deep learning DeepSurv survival prediction model were constructed. The C-index values of the training set were 0.687 and 0.770, and the C-index values of the test set were 0.606 and 0.763,respectively. Conclusion: Compared with the traditional Cox model, the DeepSurv model can more accurately predict the survival probability of patients with ICC undergoing adjuvant chemotherapy at a certain time point, and more accurately judge the survival benefit of adjuvant chemotherapy.

Objectives: To construct a nomogram for prediction of intrahepatic cholangiocarcinoma (ICC) lymph node metastasis based on inflammation-related markers,and to conduct its clinical verification. Methods: Clinical and pathological data of 858 ICC patients who underwent radical resection were retrospectively collected at 10 domestic tertiary hospitals in China from January 2010 to December 2018. Among the 508 patients who underwent lymph node dissection,207 cases had complete variable clinical data for constructing the nomogram,including 84 males,123 females,109 patients≥60 years old,98 patients<60 years old and 69 patients were pathologically diagnosed with positive lymph nodes after surgery. Receiver operating characteristic curve was drawn to calculate the accuracy of preoperative imaging examinations to determine lymph node status,and the difference in overall survival time was compared by Log-rank test. Partial regression squares and statistically significant preoperative variables were screened by backward stepwise regression analysis. R software was applied to construct a nomogram,clinical decision curve and clinical influence curve,and Bootstrap method was used for internal verification. Moreover,retrospectively collecting clinical information of 107 ICC patients with intraoperative lymph node dissection admitted to 9 tertiary hospitals in China from January 2019 to June 2021 was for external verification to verify the accuracy of the nomogram. 80 patients with complete clinical data but without lymph node dissection were divided into lymph node metastasis high-risk group and low-risk group according to the score of the nomogram among the 858 patients. Log-rank test was used to compare the overall survival of patients with or without lymph node metastasis diagnosed by pathology. Results: The area under the curve of preoperative imaging examinations for lymph node status assessment of 440 patients was 0.615,with a false negative rate of 62.8% (113/180) and a false positive rate of 14.2% (37/260). The median survival time of 207 patients used to construct a nomogram with positive or negative postoperative pathological lymph node metastases was 18.5 months and 27.1 months,respectively (P<0.05). Five variables related to lymph node metastasis were screened out by backward stepwise regression analysis,which were combined calculi,neutrophil/lymphocyte ratio,albumin,liver capsule invasion and systemic immune inflammation index,according to which a nomogram was constructed with concordance index(C-index) of 0.737 (95%CI: 0.667 to 0.806). The C-index of external verification was 0.674 (95%CI:0.569 to 0.779). The calibration prediction curve was in good agreement with the reference curve. The results of the clinical decision curve showed that when the risk threshold of high lymph node metastasis in the nomogram was set to about 0.32,the maximum net benefit could be obtained by 0.11,and the cost/benefit ratio was 1∶2. The results of clinical influence curve showed that when the risk threshold of high lymph node metastasis in the nomogram was set to about 0.6,the probability of correctly predicting lymph node metastasis could reach more than 90%. There was no significant difference in overall survival time between patients with high/low risk of lymph node metastasis assessed by the nomogram and those with pathologically confirmed lymph node metastasis or without lymph node metastasis (Log-rank test:P=0.082 and 0.510,respectively). Conclusion: The prediction accuracy of preoperative nomogram for ICC lymph node metastasis based on inflammation-related markers is satisfactory,which can be used as a supplementary method for preoperative diagnosis of lymph node metastasis and is helpful for clinicians to make personalized decision of lymph node dissection for patients with ICC.

Objective: To analyze the clinical characteristics of children with Burkitt lymphoma (BL) and to summarize the mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 (CNCL-B-NHL-2017) regimen. Methods: Clinical features of 436 BL patients who were ≤18 years old and treated with the CNCL-B-NHL-2017 regimen from May 2017 to April 2021 were analyzed retrospectively. Clinical characteristics of patients at disease onset were analyzed and the therapeutic effects of patients with different clinical stages and risk groups were compared. Survival analysis was performed by Kaplan-Meier method, and Cox regression was used to identify the prognostic factors. Results: Among 436 patients, there were 368 (84.4%) males and 68 (15.6%) females, the age of disease onset was 6.0 (4.0, 9.0) years old. According to the St. Jude staging system, there were 4 patients (0.9%) with stage Ⅰ, 30 patients (6.9%) with stage Ⅱ, 217 patients (49.8%) with stage Ⅲ, and 185 patients (42.4%) with stage Ⅳ. All patients were stratified into following risk groups: group A (n=1, 0.2%), group B1 (n=46, 10.6%), group B2 (n=19, 4.4%), group C1 (n=285, 65.4%), group C2 (n=85, 19.5%). Sixty-three patients (14.4%) were treated with chemotherapy only and 373 patients (85.6%) were treated with chemotherapy combined with rituximab. Twenty-one patients (4.8%) suffered from progressive disease, 3 patients (0.7%) relapsed, and 13 patients (3.0%) died of treatment-related complications. The follow-up time of all patients was 24.0 (13.0, 35.0) months, the 2-year event free survival (EFS) rate of all patients was (90.9±1.4) %. The 2-year EFS rates of group A, B1, B2, C1 and C2 were 100.0%, 100.0%, (94.7±5.1) %, (90.7±1.7) % and (85.9±4.0) %, respectively. The 2-year EFS rates was higher in group A, B1, and B2 than those in group C1 (χ²=4.16, P=0.041) and group C2 (χ²=7.21, P=0.007). The 2-year EFS rates of the patients treated with chemotherapy alone and those treated with chemotherapy combined with rituximab were (79.3±5.1)% and (92.9±1.4)% (χ²=14.23, P<0.001) respectively. Multivariate analysis showed that stage Ⅳ (including leukemia stage), serum lactate dehydrogenase (LDH)>4-fold normal value, and with residual tumor in the mid-term evaluation were risk factors for poor prognosis (HR=1.38,1.23,8.52,95%CI 1.05-1.82,1.05-1.43,3.96-18.30). Conclusions: The CNCL-B-NHL-2017 regimen show significant effect in the treatment of pediatric BL. The combination of rituximab improve the efficacy further.
Adolescent ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use* ; Burkitt Lymphoma/drug therapy* ; Child ; Disease-Free Survival ; Female ; Humans ; Lactate Dehydrogenases ; Lymphoma, B-Cell/drug therapy* ; Male ; Prognosis ; Retrospective Studies ; Rituximab/therapeutic use* ; Treatment Outcome

Objective: To explore the diagnostic value and model of serum Golgi protein 73 (GP73) in patients with hepatitis C cirrhosis. Methods: 271 cases with chronic hepatitis C virus infection who were treated in the Fifth Medical Center of PLA General Hospital from January 2010 to December 2017 were retrospectively collected as the research objects, including 126 cases with hepatitis and 145 cases with liver cirrhosis. Serum GP73 and liver stiffness measurement (LSM) based on transient elastography test were performed in all patients. Simultaneously, blood routine, liver function, coagulation function and other related indicators were collected. GP73 diagnostic efficiency for liver cirrhosis was evaluated by receiver operating characteristic curve (ROC). GP73 diagnostic value was clarified after comparison with aspartate aminotransferase/platelet ratio index (APRI), FIB-4 index (FIB-4) and LSM. Compensated hepatitis C virus-related cirrhosis diagnostic model based on serological index was established by logistic regression analysis. Results: The area under the receiver operating characteristic curve (AUC) of GP73, LSM, FIB-4 and APRI in the diagnosis of compensated hepatitis C virus-related cirrhosis were 0.923, 0.839, 0.836 and 0.800 respectively, and GP73 had the best diagnostic efficiency (P <0.001). LSM and GP73 combined use had improved the diagnostic sensitivity of cirrhosis to 97.24%. Multivariate logistic regression analysis revealed that GP73, age, and platelets were independent predictors of cirrhosis.Compensated hepatitis C virus-related cirrhosis diagnostic model (GAP) was established based on the result: LogitP=1/[1+exp(6.145+0.013×platelet-0.059×age-0.059×GP73)].AUC model for diagnosing compensated liver cirrhosis was 0.944, and the optimal cut-off value was 0.56, with sensitivity and specificity of 84.03% and 92.06%, respectively, and the diagnostic efficiency of this model was better than that of APRI, FIB-4, LSM and GP73 alone (P<0.05). Conclusion: GP73 is a reliable serum biomarker for the diagnosis of compensated hepatitis C virus-related cirrhosis. The GAP diagnostic model based on GP73, platelet count, and age can further improve the diagnostic efficiency and help to diagnose patients with compensated hepatitis C virus-related cirrhosis.
Aspartate Aminotransferases ; Biomarkers ; Fibrosis ; Hepatitis C ; Hepatitis C, Chronic/complications* ; Humans ; Infant, Newborn ; Liver/pathology* ; Liver Cirrhosis/pathology* ; Polyesters ; ROC Curve ; Retrospective Studies

Abstract: Objective To evaluate the key quality control and protective performance test of Halcyon medical linear accelerator. Methods WS 674-2020Specification for Testing of Quality Control in Medical Linear Accelerator（ According to the hereinafter WS 674-2020） ， referred to and the manufacturer´s manual the performance of the first Halcyon medical linear accelerator in Results ， ， Hunan Province was tested. The results showed that all ten indicators of the accelerator including dose deviation ， ， （ ， ， ， - repeatability linearity daily stability and symmetry the results were 0.10% 0.03% 0.04% 0.50% and 100.50% 100.80% ）， - - respectively met the requirements of WS 674 2020. The results of manufacturer quality control indicators such as dose rate ， ， stability in beam gantry rotation isocenter and mechanical position accuracy megavolt image parameters and cone beam computer tomography image parameters met the requirements of the manufacturer´s regulations. Due to the special structure and ， - ： function of the accelerator it is difficult to detect the parameter required by WS 674 2020 as below the radiation leakage - ， ， ， ， outside the M zone the uniformity the indicators related to the light field the offset of the radiation beam axis the zero scale Conclusion - position of the rotating motion scale and others. It is difficult to carry out complete testing according to WS 6742020 for Halcyon medical linear accelerator and it is urgent for the state to issue relevant testing standards to standardize and strengthen the quality control testing of various accelerators.

Abstract: Objective To follow up and evaluate the stability testing status of γ stereotactic radiotherapy system (hereinafter γ knife WS 582-2017 Specifications for Testing of Quality Control in X and γ referred to ) in medical institutions based on the RayStereotactic Radiotherapy System WS 582-2017 Methods (hereinafter referred to ). A total of 43 medical institutions using γ knife and 54 medical physics personnel were recruited as the research subjects by random sampling method. Based on the - - standard tracking evaluation method, we followed up the evaluation of γ knife stability testing based on WS 582 2017. Results - Only 66.7% of the 54 subjects preformed WS 582 2017 in their daily work. Only 30.2% (all were tertiary hospital) of 43 medical institutions were equipped with complete quality control and testing equipment. The implementation rate of γ knife stability test was 67.4%, and it was not carried out in strict accordance with the test events and test cycle requirements - specified in the WS 582 2017. There were incomplete test events, incomplete records or test cycles that did not meet the Conclusion standard requirements in γ knife stability test. Medical institutions did not carry out γ knife stability tests in strict - accordance with the projects and cycle required by the WS 582 2017. The reasons are related to medical institutions are not equipped with complete testing equipment, the personnel are lack of understanding of relevant national standards, the poor publicity and implementation of the standards, the lack of standardized training channels and inadequate health supervision.