To address the limitations of traditional minimally invasive thermal ablation technology such as poor conformability, carbonization and electromagnetic radiation, this paper proposes a steam thermal ablation technology that uses saturated steam internal energy to replace the traditional electromagnetic radiation energy. Through the steam thermal ablation system and the steam thermal ablation needle designed based on simulation, the ex vivo pig liver experiments were carried out. The results have the characteristics of the maximum ablation axis ratio (short diameter / long diameter) and non-carbonization with the same type of thermal ablation technology. Based on the near-infrared light, in this paper the curative effect of the reduced scattering coefficient of the steam thermal ablation results was evaluated. The reduced scattering coefficients of the coagulation area all exceeded 16, reaching the completely damaged state, which verified that the steam thermal ablation can effectively inactivate the tumor cells.
Steam ; Animals ; Swine ; Liver Neoplasms/surgery* ; Ablation Techniques/methods* ; Liver/surgery* ; Equipment Design

The minimally invasive thermal ablation technology differs from traditional surgical operations, which requires auxiliary equipment to evaluate ablation results. However, the ultrasound and CT currently used in clinical practice have shortcomings such as artifacts and radiation. Therefore, this paper proposes a design for a minimally invasive thermal ablation evaluation system based on the principle of electrical impedance tomography technology to monitor the ablation range. At the same time, the innovative introduction of a programmable gain feedforward signal as the parameter signal of the multiplier demodulator in the electrical impedance tomography system design can effectively solve the problem of weak signals being submerged in noise and improve imaging accuracy. The system controls the amplitude of the excitation current signal and the acquisition / processing of boundary voltages via an STM32, uploads the collected data to an upper computer, and reconstructs the conductivity distribution using the Newton-Raphson algorithm to map the size of the ablation area. Experimental results show that the system can effectively reflect the size of the microwave ablation area. Under the same minimally invasive ablation parameters, the average imaging errors are 0.6 mm for the long diameter, 0.8 mm for the short diameter, and 1.75% for the axial ratio (long diameter / short diameter), demonstrating high consistency. This verifies the technical potential of electrical impedance tomography in minimally invasive thermal ablation.
Electric Impedance ; Tomography/instrumentation* ; Equipment Design

Background Aluminum and fluoride are neurotoxic, and aluminum exposure alone is closely related to the overall cognitive function of operational workers. It is unclear about the effect of aluminum and fluoride interactions on cognitive function. Objective To evaluate a potential interaction effect of blood aluminum and urinary fluoride on the overall cognitive function of workers working in an aluminum plant. Methods Using cluster sampling, 230 workers in the electrolysis workshop of an aluminum group company in Shanxi Province were selected, and plasma aluminum concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS) and urinary fluoride by ion-selective electrode. The study participants were divided into a low blood aluminum group and a high blood aluminum group according to the median (M) of blood aluminum concentration, and a low urinary fluoride group and a high urinary fluoride group by a predetermined cutoff point (2.160 mg·L⁻¹). The Montreal Cognitive Assessment-Beijing (MoCA-BJ) was used to assess overall cognitive function of the workers. Logistic regression model was used to analyze the relationship between blood aluminum, urinary fluoride, and mild cognitive impairment (MCI), including multiplicative interaction analysis and correlation analysis; R language was used to fit an additive interaction model of blood aluminum and urinary fluoride on MCI and to calculate synergy index (S), relative excess risk due to interaction (RERI), and attributable proportion due to interaction (API). Results Among the 230 operational workers, the median blood aluminum concentration (P₂₅, P₇₅) was 40.11 (25.16, 58.89) µg·L⁻¹, and there were 104 cases of abnormal urinary fluoride, with an abnormality rate of 45.2%. There was a multiplicative interaction (OR=7.783, 95%CI: 1.377, 43.991) and no additive interaction (RERI=0.030, 95%CI: −0.498, 0.559; API=0.018, 95%CI: −0.279, 0.316; S=1.049, 95%CI: 0.519, 2.118) for the effect between blood aluminum and urinary fluoride on overall cognitive function of the workers. The logistic regression analysis showed that the risk of MCI was 12.105 (95%CI: 2.802, 52.287) times higher in workers with both high blood aluminum and high urinary fluoride than in those with low blood aluminum and low urinary fluoride, after adjusting for selected influencing factors. Conclusion Occupational exposure related high blood aluminum and high urinary fluoride are risk factors for cognitive dysfunction, and the coexistence of both indicators increases the risk of MCI in workers with occupational aluminum exposure, with a multiplicative interaction.

At present , methamphetamine has become a major hidden danger in global public health safety. In order to judge methamphetamine addicts and methamphetamine abstainers more scientifically and reliably, this study analyzed the endogenous metabolites in plasma, serum and urine of methamphetamine addicts, methamphetamine abstainers and healthy volunteers by highly sensitive high-throughput liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) analytical instrument. The obtained metabolomic data were processed by univariate analysis (t-test) and multivariate analysis (PLS-DA and OPLS-DA) and eligible potential biomarkers were then screened.The identified biomarkers set enrichment analysis to find the connection between metabolites and metabolic pathways.Multivariate statistical results showed that methamphetamine acute group, recovery group and healthy group were clearly separated.3, 18 and 6 regulated metabolites were identified in serum, plasma and urine, respectively, suggesting that lipid metabolism was abnormal in methamphetamine acute group, and that fatty acid metabolism, sulfate/sulfite metabolism and sex hormone metabolism were abnormal in methamphetamine recovery group.The selected potential biomarkers in this study provide the possibility for scientific judgment of the clinical stage of methamphetamine detoxification.

Objective:To analyze the distribution and drug resistance of wound pathogenic microorganisms in outpatients of wound healing center so as to provide a basis for the standardized construction of wound healing centers.Methods:A retrospective case series study was used to analyzed the data of 365 outpatients treated at Ruijin Hospital, Shanghai Jiaotong University School of Medicine from December 2017 to October 2019. There were 220 males and 145 females, aged (58.8±18.9)years (range, 18-98 years). The patients included 92 first-visit patients and 273 re-visit patients. The culture results (positive rate of pathogenic microorganisms, bacterial species, bacterial distribution) and drug sensitivity results of the wound secretions were compared and analyzed.Results:(1) Among 365 samples of wound secretions, 198 patients were positive for pathogenic microorganisms with a positive rate of 54.3%. A total of 107 strains (51.0%) of Gram-positive bacteria were detected, mainly Staphylococcus aureus (70 strains, 33.3%); 95 strains (45.2%) of Gram-negative bacteria were detected, mainly Escherichia coli (20 strains, 9.5%), followed by Pseudomonas aeruginosa (17 strains, 8.1%); 8 strains (3.8%) of fungi were detected. (2) A total of 26 (28.3%) first-visit patients were positive for pathogenic microorganisms, and 172 (63.0%) re-visit patients were positive for pathogenic microorganisms. The rate of positive microorganism detection had significant differences between first-visit and re-visit patients ( P<0.05). (3) A total of 29 strains were detected in first-visit patients, including 16 strains (55.2%) of Gram-positive bacteria, 11 strains (37.9%) of Gram-negative bacteria and 2 strains (6.9%) of fungi. A total of 181 strains were detected in re-visit patients, including 91 strains (50.3%) of Gram-positive bacteria, 84 strains (46.4%) of Gram-negative bacteria and 6 strains (3.3%) of fungi. The microbial distribution was significantly different between first-visit and re-visit patients ( P<0.05). (4) Compared with first-visit patients, the resistance of Staphylococcus aureus isolated from the re-visit patients to spenicillin, oxacillin, ciprofloxacin, tetracycline, clindamycin, moxifloxacin, erythromycin, and levofloxacin were increased variably. No vancomycin-resistant Staphylococcus aureus was detected, indicating that the staphylococcus aureus presented in the wound was highly sensitive to vancomycin. Conclusions:Staphylococcus aureus is the most common microorganism in wound secretions in outpatients of wound healing center. The rate of positive pathogenic microorganisms in wound secretions of re-visit patients is significantly higher than that of first-visit patients, and the distribution of pathogenic microorganisms of first-visited and revisited patients differs significantly. The Staphylococcus aureus detected in re-visit patients has a higher resistance to common antibiotics compared with first-visit patients. It is suggested that timely detection of pathogenic microorganisms in outpatients and effective control and supervision of outpatient infections are important contents that cannot be ignored in the construction of wound healing center.

Objective:To explore the effect of occupational aluminum (Al) exposure on workers' overall cognitive level and speech function.Methods:In July 2019, by using cluster sampling method, the group of 232 exposed to Al from an Al plant in Shanxi Province were selected as the exposed group, and the group of 228 not exposed to Al were selected as the control group. The blood Al concentration was determined by inductively coupled plasma mass spectrometry (ICP-MAS) . The exposed group was divided into high exposure group and low exposure group according to the median ( M) concentration of Al in serum. The general cognitive function and speech function were evaluated with the Montreal Cognitive Assessment Scale (MoCA) , and the differences in the general cognitive function and speech function between the groups were compared, and non-conditional logistic regression was used to analyze the possible influencing factors of mild cognitive impairment (MCI) . Results:There were significant differences in age, working age, education and drinking status between Al exposed group and control group ( P<0.05) . The total MoCA score, animal naming tese (ANT) score and category fluency repetition (CFT) score in Al exposure group were lower than control group and the differences were statistically significant ( P<0.05) . The full rate of ANT was lower than that of CFT in Al exposure group ( P<0.05) . The total MoCA score, ANT score and CFT score in the high exposure group were significantly lower than those in the control group ( P<0.05) . The score of MoCA, ANT and CFT in high exposure group were lower than those in low exposure group between the level of serum aluminum>60 μg/L group and ≤60 μg/L group ( P<0.05) . Logistic regression analysis showed that working age, serun Al concentration, ANT score, CFT score and SR score were the possible influencing factors of MCI in occupational Al exposure workers ( P<0.05) . Conclusion:Occupational Al exposure can lead to impaired speech function of workers, the higher the ANT score, CFT score and SR score, the lower working age and serum Al concentration, the lower risk of MCI.

Objective:To explore the effect of occupational aluminum (Al) exposure on workers' overall cognitive level and speech function.Methods:In July 2019, by using cluster sampling method, the group of 232 exposed to Al from an Al plant in Shanxi Province were selected as the exposed group, and the group of 228 not exposed to Al were selected as the control group. The blood Al concentration was determined by inductively coupled plasma mass spectrometry (ICP-MAS) . The exposed group was divided into high exposure group and low exposure group according to the median ( M) concentration of Al in serum. The general cognitive function and speech function were evaluated with the Montreal Cognitive Assessment Scale (MoCA) , and the differences in the general cognitive function and speech function between the groups were compared, and non-conditional logistic regression was used to analyze the possible influencing factors of mild cognitive impairment (MCI) . Results:There were significant differences in age, working age, education and drinking status between Al exposed group and control group ( P<0.05) . The total MoCA score, animal naming tese (ANT) score and category fluency repetition (CFT) score in Al exposure group were lower than control group and the differences were statistically significant ( P<0.05) . The full rate of ANT was lower than that of CFT in Al exposure group ( P<0.05) . The total MoCA score, ANT score and CFT score in the high exposure group were significantly lower than those in the control group ( P<0.05) . The score of MoCA, ANT and CFT in high exposure group were lower than those in low exposure group between the level of serum aluminum>60 μg/L group and ≤60 μg/L group ( P<0.05) . Logistic regression analysis showed that working age, serun Al concentration, ANT score, CFT score and SR score were the possible influencing factors of MCI in occupational Al exposure workers ( P<0.05) . Conclusion:Occupational Al exposure can lead to impaired speech function of workers, the higher the ANT score, CFT score and SR score, the lower working age and serum Al concentration, the lower risk of MCI.

OBJECTIVE: To explore the relationship between occupational aluminum exposure and fasting blood glucose level in workers. METHODS: A cluster sampling method was used to select 178 occupational aluminum-exposed workers as the exposure group, and 178 workers without occupational aluminum exposure as the control group in a large aluminum factory in Shanxi Province. Glucose oxidase method was used to measure the fasting blood glucose level, and inductively coupled plasma mass spectrometry was used to measure the plasma aluminum level in these workers. A generalized linear model was used to analyze the correlation between plasma aluminum exposure level and fasting blood glucose in these workers. RESULTS: The blood aluminum level of workers in the exposure group was higher than that of the control group [median: 39.58 vs 16.67 μg/L, P<0.01]. The fasting blood glucose level of workers in the exposure group was higher than that of the control group [(5.33±0.79) vs(5.15±0.41) mmol/L, P<0.01]. The results of the generalized linear model analysis showed that the blood aluminum level of workers was positively correlated with their fasting blood glucose level after adjusting for age, body mass index, smoking, drinking, exercise, family history of diabetes, and incidence of diabetes(P<0.05). There was a dose-response relationship between the blood aluminum level and fasting blood glucose level of workers in the groups of junior high school and below and high school(all P_(trend)<0.01). There was no correlation found between blood aluminum level and fasting blood glucose level in the group of college and above(P_(trend)>0.05). There was a dose-response relationship between the blood aluminum level and the fasting blood glucose level in the workers in the non-exercise group(P_(trend)<0.01). There was no correlation found between the blood aluminum level and the fasting blood glucose level in the exercise group(P_(trend)>0.05). CONCLUSION: The blood aluminum level of workers exposed to occupational aluminum is positively correlated with their fasting blood glucose level. Higher education level or exercise can moderately reduce the effect of blood aluminum level on fasting blood glucose.

Objective To explore the method of isolation, identification and in vitro differentiation of islet stem cells in neonatal rat. Methods The whole pancreata of neonatal rats were digested with collagenase, then,under the (condition) of pH 7.4～7.6,the digested tissue fragments were cultured with serum and serum-free RPMI 1640 (( bFGF), EGF, N2).The whole formation process of new islet cell-like cell masses was examined.The insulin (release) test was used to detect islet function. The expression of nestin was tested by immunocytochemistry. Results The nestin positive cells can be found within 36 h of culture of the digested pancreatic fragments.After addition of bFGF,ECF,N2,nestin positive cells proliferated fast and formed new islets-like cell masses after 18～24 d, and (insulin)ssion could be confirmed. Conclusions The nestin positive cells of pancreatic cells possess the character of islet stem cells, and can form islet like cell masses through culture in vitro.