Hemodynamic monitoring can reflect cardiac function and blood perfusion and is an indispensable monitoring method in clinical practice. Invasive hemodynamic monitoring methods represented by the thermodilution method are limited in their clinical application scope because they require vascular cannulation. Non-invasive hemodynamic monitoring has attracted extensive attention from medical companies and clinicians at home and abroad in recent years due to its advantages such as safety, non-invasiveness, continuous monitoring, simple operation, and low cost. This paper designs a non-invasive hemodynamic monitoring system based on the impedance cardiography, including hardware, algorithm, software design, and performance parameter evaluation. Among them, the hardware part mainly includes a differential high-frequency constant current source stimulation circuit, impedance cardiogram signal acquisition, and ECG signal acquisition circuit. Signal processing includes wave filtering, impedance cardiogram signal calibration, and ECG signal and impedance cardiogram signal feature point recognition. According to the collected impedance cardiogram and ECG signals, hemodynamic parameters such as heart rate (HR), stroke volume (SV), cardiac output (CO), stroke index (SI), cardiac index (CI), and cardiac contractility index (ICON) are calculated based on the Nyboer thoracic cylinder model. After testing, the key technical indicators of the system hardware are better than that of the relevant medical device standards. The system was used to collect impedance cardiogram and ECG signal data from 40 volunteers. The calculated HR, SV, and CO, three important hemodynamic indicators, were compared with the ICONCore non-invasive cardiac output monitor of OSYPKA Medical in Germany. Their Pearson correlation coefficients were 0.992 ( P<0.001), 0.948 ( P<0.001), and 0.933 ( P<0.001), respectively, verifying that the designed system has high accuracy and reliability.
Cardiography, Impedance/methods* ; Humans ; Hemodynamic Monitoring/methods* ; Equipment Design ; Signal Processing, Computer-Assisted ; Hemodynamics ; Algorithms ; Monitoring, Physiologic/methods* ; Electrocardiography

End-tidal carbon dioxide monitoring is an important means of evaluating human lung function and is widely used in fields such as clinical emergency treatment and cardiopulmonary resuscitation. This paper develops a microstream end-tidal carbon dioxide monitoring system. It adopts an integrated gas circuit design to further reduce the size of the equipment. The system uses the method of calculating the root mean square (RMS) of differential pressure signals to regulate the gas circuit flow, enabling the system to stably operate at a flow state of 30 mL/min. In addition, by simultaneously detecting multiple environmental parameters such as temperature and pressure, the system realizes system state monitoring and gas parameter compensation. The test results show that various indicators of the system meet the requirements of relevant standards, laying a good foundation for subsequent engineering applications.
Carbon Dioxide/analysis* ; Equipment Design ; Monitoring, Physiologic/methods* ; Humans

In order to improve the effect of transcranial electrical stimulation treatment and realize personalized treatment for patients with varying severity levels, this paper designed an integrated four-channel EEG recording multimodal transcranial electrical stimulation system. This system can conduct real-time monitoring on EEG and related characteristic analysis before stimulation, in stimulation, and after stimulation. This enables physicians and researchers to resolve real-time brain states, evaluate transcranial electrical stimulation effect, and then artificially adjust the stimulation parameters. After relevant testing and verification, the system can select four stimulation modes: TACS, TDCS, TPCS and TRNS, which can output the constant stimulation current of 0.03 mA accuracy in the range of ±2 mA and the stimulation frequency of low frequency of 0~4 kHz (precision of 0.01 Hz) and high frequency 50~100 kHz, which can obtain more accurate EEG signals under stimulation interference, demonstrating a good market application prospect.
Electroencephalography/methods* ; Transcranial Direct Current Stimulation/instrumentation* ; Humans ; Equipment Design

This paper introduces a 16-channel multimodal high-precision transcranial electrical stimulation system specifically for non-invasive brain stimulation. This system added TMCS mixed four traditional stimulation modes with TACS, TDCS, TPCS and TRNS. By designing a compensated high-precision constant current source, the constant stimulation current with an accuracy of 0.03 mA in the range of ±2 mA and the stimulation frequency of 50~200 kHz with low frequency of 0~4 kHz (high frequency of 0.1 Hz) are realized. In TACS stimulation mode, there are five adjustable wave forms: triangular wave, sine wave, sawtooth wave, square wave and mixed wave. The system has dual closed-loop control overcurrent detection and simultaneous real-time electrode contact impedance detection. After relevant tests and verification, the system has good stimulation accuracy, high safety and reliability. Compared with the existing products at home and abroad, it features lower cost, richer stimulation mode and waveforms, demonstrating a certain market application value.
Transcranial Direct Current Stimulation/instrumentation* ; Equipment Design ; Humans

Esophageal cancer is a malignant tumor with a high incidence in China. At pesent, advanced esophageal cancer patients are still frequently encountered. The primary treatment for resectable advanced esophageal cancer is surgery-based multimodality therapy, including preoperative neoadjuvant therapy, such as chemotherapy, chemoradiotherapy or chemotherapy plus immunotherapy, followed by radical esophagectomy with thoraco-abdominal two-field or cervico-thoraco-abdominal three-field lymphadenectomy via minimally invasive approach or thoracotomy. In addition, adjuvant chemotherapy, radiotherapy, or chemoradiotherapy, or immunotherapy may also be administered if suggested by postoperative pathological results. Although the treatment outcome of esophageal cancer has improved significantly in China, many clinical issues remain controversial. In this article, we summarize the current hotspots and important issues of esophageal cancer in China, including prevention and early diagnosis, treatment selection for early esophageal cancer, surgical approach selection, lymphadenectomy method, preoperative neoadjuvant therapy, postoperative adjuvant therapy, and nutritional support treatment.
Humans ; Esophageal Neoplasms/surgery* ; Combined Modality Therapy ; Neoadjuvant Therapy/methods* ; Chemoradiotherapy ; Chemotherapy, Adjuvant ; Esophagectomy/methods*

The human UDP-glucuronosyltransferase 1A1 (UGT1A1), one of the most essential conjugative enzymes, is responsible for the metabolism and detoxification of bilirubin and other endogenous substances, as well as many different xenobiotic compounds. Deciphering UGT1A1 relevance to human diseases and characterizing the effects of small molecules on the activities of UGT1A1 requires reliable tools for probing the function of this key enzyme in complex biological matrices. Herein, an easy-to-use assay for highly-selective and sensitive monitoring of UGT1A1 activities in various biological matrices, using liquid chromatography with fluorescence detection (LC-FD), has been developed and validated. The newly developed LC-FD based assay has been confirmed in terms of sensitivity, specificity, precision, quanti-tative linear range and stability. One of its main advantages is lowering the limits of detection and quantification by about 100-fold in comparison to the previous assay that used the same probe substrate, enabling reliable quantification of lower amounts of active enzyme than any other method. The precision test demonstrated that both intra- and inter-day variations for this assay were less than 5.5％. Further-more, the newly developed assay has also been successfully used to screen and characterize the regu-latory effects of small molecules on the expression level of UGT1A1 in living cells. Overall, an easy-to-use LC-FD based assay has been developed for ultra-sensitive UGT1A1 activities measurements in various biological systems, providing an inexpensive and practical approach for exploring the role of UGT1A1 in human diseases, interactions with xenobiotics, and characterization modulatory effects of small mole-cules on this conjugative enzyme.

Objective To investigate the effects of adoptive reinfusion of regulatory T cell (Treg) on the recovery of islet function and graft survival time after islet allograft transplantation. Methods The diabetic model was established using C57BL/6 mice as recipients, and Balb/c mice were chosen as donors for islet allografts transplantation beneath the renal capsule. The recipient mice were divided into 3 groups and 3 mice in each group according to different processing Methods: Treg experiment group (Treg group, 1×10⁶ Treg cells were injected via tail vein at 1 d before operation), positive control group [sirolimus (SRL) group, SRL at a dose of 300 μg/(kg·d) was intragastrically given every day from 1 d before operation] and blank control group (control group, an equivalent volume of normal saline was intragastrically given every day from 1 d before operation). Enzyme-linked immune absorbent assay (ELISA) was used to detect the changes of blood glucose and C-peptide in mice within 14 days after transplantation. In vivo imaging technique was used to dynamically monitor the survival of mice within 14 days after transplantation. Results In each group, the blood glucose levels at postoperative 3 d were significantly decreased compared with those before transplantation (all P < 0.001). At postoperative 1 d, the C-peptide levels showed an explosive rise to varying degree in each group. At postoperative 3 d, the C-peptide levels in each group were significantly higher than that before operation (all P < 0.001). At the end of the observation period at 14 d after operation, the C-peptide levels in the SRL and Treg groups were (427±50) pmol/L and (833±57) pmol/L, relatively higher than that in the control group. But the blood glucose levels were (14.5±0.5) mmol/L and (12.1±0.6) mmol/L, significantly lower than that in the control group (all P < 0.001). Compared with the SRL group, the explosive release amount of C-peptide was significantly lower, the declining trend was more remarkably stable, and the C-peptide level was considerably higher in the Treg group at the end of the observation period (all P < 0.001). At postoperative 14 d, the grafts were almost completely apoptotic in the control group, over 50% of the grafts survived in the SRL group, and over 80% of the grafts survived in the Treg group. Conclusions Adoptive reinfusion of Treg cells can effectively protect islet grafts, prolong the survival time of grafts, and maintain the normal levels of blood glucose and C-peptide in the recipient mice.

Objective To explore the effects of Qa-1 and PD-L1 loaded artificial liposomal treatment in allograft rejection and its outcomes .Methods The extracellular domains of Qa-1 and PD-L1 were loaded on liposome surface by streptavidin-biotin system . Mixed lymphocyte reaction (MLR) was performed for measuring Qa-1/PD-L1 liposome biological function .Then liposome was co-transplanted with allo-islets via portal vein .The levels of blood glucose and C-peptide were detected daily after transplantation .Also hepatic lymphocytes after transplantation were isolated for determining the proportion of activated cells and signaling pathway changes .Results Artificial liposome could be easily loaded with biotinylated peptide and its diameter was between 50 to 500 nm . Qa-1/PD-L1 liposome could significantly suppress lymphocyte proliferation , activation and secretion of IFN-γ in MLR by an activation of SHP1/2 and an inhibition of Syk pathway .Qa-1/ PD-L1 liposomes could suppress the activation of hepatic lymphocytes in vivo by activating SHP1/2 ,protecting islet allografts and maintaining a normal level of blood glucose in recipients .Conclusions Qa-1/PD-L1 loaded liposome can effectively suppress allograft rejection and improve the outcomes of islet transplantation .

Purpose To investigate the expression of signal transduction and activator 3 (Stat3) ,and phosphorylated Stat3 (p-Stat3) in human gastric cancer cell lines MGC-803 and BGC-823,and to explore the role of p-Stat3 in the invasion and migration of gastric cancer. Methods The expressed Stat3 and p-Stat3 in gastric cancer MGC-803 and BGC-823 cells were investigated by flow cytometry,and the migration and invasion abilities of cancer cells were observed using scratch test and in vitro Transwell test. Results Flow cytometry showed that the expression of Stat3 in MGC-803 and BGC-823 cells was basically unchanged before and after IL-6 stimulation (10 ng/mL) ,and the activated p-Stat3,however,was significantly higher after IL-6 stimulation. The activated p-Stat3 in BGC-823 cells was higher than that of MGC-803 cells (P < 0. 001) . The results of scratch tests showed that the scar healing area of BGC-823 cells was significantly larger than that of MGC-803 cells after 48 h (P = 0. 031) . Transwell cell experiments showed that the number of penetrating cells from BGC-823 cell line were significantly greater than those from MGC-803 cell line (P < 0. 001) . Conclusion Over activated p-Stat3 enhances the invasion and migration of MGC-803 and BGC-823 gastric cancer cells.

BACKGROUND:Previous studies on immunosuppression and anti-rejection after organ transplantation mainly focused on effects of T lymphocytes-mediated immune response and immunosuppressive agents on T lymphocytes. Effects of dendritic cel s were unclear. The manifestation and mechanism of immunosuppressive agent effects on dendritic cel s are not identical. OBJECTIVE:To compare the effects of different immunosuppressive agents on expression and function of costimulatory molecules of dendritic cel s, and to explore the mechanism of action of immunosuppressive agents. METHODS:20μg/L rapamycin, 0.04 mg/L mycophenolate, 10μg/L tacrolimus and 1 mg/L cyclosporine A were separately added during bone marrow cel s of C57BL/6 mice were differentiated into dendritic cel s. RESULTS AND CONCLUSION:Flow cytometry results revealed that CD40 expression in each group:rapamycin0.05). One-way mixed lymphocyte reaction results displayed dendritic cel costimulatory T cel proliferation in each group:rapamycin