BACKGROUND: The event of paroxysmal deplorizing shift (PDS) is the cellular hallmark of brain neurons of epileptiform activities. Its development used to be considered to be related to abnormal synaptic interactions. Recertly, the intrinsic nature of PDS has received more attention.OBJECTIVE: To observe the characteristics of epileptiform activities of rat hippocampal CA1 pyramidal neurons induced by low-dosage veratridine and investigate its possible ion mechanism.DESIGN: An exploratory and observational trial.SETTING: Institute of Neuroscience, Fourth Military Medical University of Chinese PLA.MATERIALS: This study was conducted at the Institute of Neuroscience,Fourth Military Medical University of Chinese PLA, from October 2002 to October 2004. Forty healthy SD rats of 14 days old were selected. Drugs were provided from Tianjin Drug Company and Sigma Company.METHODS: Rats were anesthetized by intraperitoneal injection, and their brain was removed and cut into slices. Epileptiform activities were induced by 0.5 μ mol/L veratridine. Then 80 nmol/L tetrodotoxin was added into the perfused solution on 6 cerebral slices, and 5 μmol/L phenytoin was used on another 5 cerebral slices. The electrophysiological characteristics of the cells under the effect of different kinds of drugs were observed.MAIN OUTCOME MEASURE: Discharge pattern of cells and tetrodotoxin-sensitive sodium currents under voltage-clamp configuration through Ⅰ-Ⅴ reaction.RESULTS: After perfusion of 0.5 μmol/L veratridine, the rat pyramidal neurons in CA1 area displayed relatively fixed-mode of runs of PDS bursting,followed by the hyperpolarization of cell membrane. Such epileptiform activities were blocked either by 80 nmol/L tetrodotoxin or 5 μnol/L phenytoin. The tetrodotoxin-sensitive sodium currents in epileptic neurons and normal controls under voltage-clamp configuration on holding potential of -55 rmV, -60 rmV, -65 mV. This shows that persistent sodium currents could be improved by low-dosage veratridine in a voltage-dependent manner.CONCLUSION: Low-dosage veratridine may induce runs of PDS like epileptiform activities on rat CA1 pyramidal neurons. Such changes can be blocked by low-dosage tetrodotoxin or phenytoin. Its ion mechanism may be related to persistent sodium currents.

Objective To summarize the experience of individualized treatment for hepatic artery thrombosis after liver transplantation.Methods From October 2002 to January 2015,5 patients with hepatic artery thrombosis after liver transplantation were treated with surgical exploration,interventional therapy or thrombolytic therapy according to the reasons.Results All the 5 patients were cured without serious complications.Conclusions There are many reasons for the occurrence of hepatic artery thrombosis after liver transplantation.Early diagnosis is the key point,and individual treatment highlights the concept of precision medicine.

Aim To observe the production of anti-idiotypic antibodies directed against AK auto Ab in the rabbit sera after long-term, high dose allogenic AK auto Ab injection. Methods Allogenic AK auto Ab (5mg/kg)was injected intramuscularly to rabbit once every other day for 90 days. Anti-idiotypic antibodies in rabbit sera were detected by ELISA. Results Rabbits injected with AK auto Ab generated anti-idiotypic antibodies that could react to F(ab′ )2 of AK auto Ab. The titers of anti-idiotypic antibodies reached the highest levels at 4 weeks after the administration of AK auto Ab and then gradually decreased. Conclusion Rabbits could be induced to form immune tolerance when high-does allogenic AK auto Ab is administrated for long-term.

Objective To construct and express human ScFv against keratin in E.coli,and identify its binding activity with antigens and antigenic specificity.Methods By genetic engineering technology,human anti-keratin ScFv was constructed from Fab fragment selected from established semi-synthetic phage antibody library.The binding activity with antigens and antigenic specificity of expressed products were i-dentified by ELISA.Results Results of DNA sequence analysis showed that nucleotide sequence of V?and VH of ScFv gene was similar to that of V?and VH of Fab gene,suggesting that there was no mutation in the construction of ScFv.The soluble anti-keratin ScFv was found to have a good antigenic specificity as well as excellent binding activity with target antigens by ELISA.However,the binding activity of ScFv with keratin was lower than that of Fab.Conclusions The successful expression and identification of human an-ti-keratin ScFv might lay a solid foundation for further observation of biological activities of anti-keratin au-toantibody,manufacture of genetic-engineering anti-keratin products,and promotion of clinical application of genetic-engineering anti-keratin antibodies.

Objective:To explore the clinical diagnosis and treatment of invasive gastrointestinal fungal infection plus pulmonary infection after renal transplantation.Methods:Clinical data were analyzed retrospectively for one patient with invasive fungal infection plus pulmonary infection after renal transplantation. The middle-aged female recipient underwent allogeneic kidney transplantation due to end-stage uremia. After successful kidney transplantation, there was postprandial epigastric pain not relieved by proton pump inhibitor. Gastroscopy after admission suggested that the nature of gastric mucosal lesions was to be determined. Pathological examination and special staining confirmed mucor.Results:After clarifying her conditions, the doses of such immunosuppression as tacrolimus, mycophenolate mofetil and prednisone were tapered and discontinued when necessary and using amphotericin B liposome plus posaconazole alleviated the digestive tract symptoms. Chest tightness, fever, shortness of breath after activities hinted at pulmonary infection after renal transplantation. Treatment was guided by the results of sputum culture.Conclusions:Mucor infection is rare in digestive tract complicated with pulmonary infection after renal transplantation. Clinicians should actively search for etiological evidence, seek multidisciplinary consultations for a definite diagnosis and provide empirical anti-infection treatments. Due attention is to be paid for double infection caused by anti-infection treatments and anti-infection treatment strategy should be timely adjusted and the dosage of immunosuppressant based upon immune monitoring.

Objective:To study the predictive value of systemic immune-inflammation index (SII), alpha-fetoprotein (AFP) and tumor diameter on microvascular invasion (MVI) in patients with resectable hepatocellular carcinoma (HCC), with an aim to establish a preoperative prediction model.Methods:The clinical data of 283 patients who underwent hepatectomy at the First Affiliated Hospital of Nanchang University from September 2017 to September 2020 were retrospectively analyzed. In the 283 patients with HCC who were included into this study, 249 were males and 34 were females, aged (53.7±11.0) years. Using postoperative pathology findings, these patients were divided into two groups: the MVI negative group ( n=140) and the MVI positive group ( n=143). Correlation between MVI and related indicators was analyzed using logistic regression analysis. The prediction model of MVI was then established by selecting independent risk factors. Univariate and multivariate analysis of recurrence-free survival (RFS) were performed using the Cox proportional hazards regression model. Results:Multivariate logistic regression analysis showed that AFP>400 ng/ml ( OR=2.304, 95% CI: 1.329-3.995, P=0.003), SII>376.30×10 9/L ( OR=2.249, 95% CI: 1.299-3.894, P=0.004) and tumor diameter>5 cm ( OR=2.728, 95% CI: 1.587-4.687, P<0.001) were independent risk factors for MVI. The Cox proportional hazards regression model showed that AFP ( HR=1.663, 95% CI: 1.063-2.602, P=0.026) and SII ( HR=1.851, 95% CI: 1.173-2.920, P=0.008) were independent risk factors for RFS in HCC patients. The sensitivity and specificity of the model based on SII, AFP and tumor diameter were 59.4% and 75.7%, respectively. Conclusions:SII, AFP and tumor diameter were closely related to occurrence of MVI in patients with HCC. AFP and SII were independent prognostic factors of RFS. This prediction model has certain predictive values for occurrence of MVI and prognosis of HCC patients.

Objective:To explore the diagnosis and treatment of pure red cell aplastic anemia (PRCA) caused by parvovirus B19 (HPV-B19)infection after liver transplantation (LT).Methods:Three adult PRCA patients caused by parvovirus B19 infection after LT were reviewed retrospectively.The relevant literatures were collected to sort out the detection methods and treatment of parvovirus B19 infection after LT.Results:All three patients received liver transplantation due to end-stage liver disease with massive intraoperative blood transfusion and smooth postoperative recovery.Severe anemia occurred at 1-2 Months after discharge.Hemorrhagic anemia was excluded after re-admission and PRCA was diagnosed by bone marrow aspiration and next generation sequencing (NGS). After tapering the intensity of immunosuppressive therapy, intravenous immunoglobulin (IVIG) was administered for 7-10 days and hemoglobin soon normalized.A review of 15 recent literatures on HPV-B19 infection after LT revealed that the diagnosis and treatment of parvovirus B19 infection after LT gradually were became same.Conclusions:HPV-B19 infection causes PRCA after LT in adults.Diagnosing with NGS, intravenous injection of immunoglobulin and modification of immunosuppressant regimen may achieve excellent therapeutic efficacies.