n-Octanol/ water partition coefficients (Kow ) is an important parameter commonly used to explain toxicity, activity and transmembrane of drugs. However, it is difficult to be detected by direct experimental determination. In this work, a set of 29 neutral and acidic analogues of naphthalene and anthraquinone with reliable experimental Kow data was chosen as model compounds for establishing linear relationship between the logarithm of apparent n-octanol/ water partition coefficient (lgKow), and the logarithm of reversed phase-high performance liquid chromatography (RP-HPLC) retention factor of the solutes corresponding to neat aqueous fraction of mobile phase (lgkw ) as the quantitative structure-retention relationship (QSRR) model. Methanol-water mixture was used as mobile phase at various pH, and retention time (tR ) was rectified by a dual-point retention time correction (DP-RTC) in this method. The experiment results indicated that the proposed QSRR model had good correlation coefficient R2 = 0. 974 -0. 976 with satisfactory results of internal and external validation (the cross-validated correlation coefficient R2cv of 0. 970-0. 973, and 1. 4% ≤relative error (RE)≤7. 9% for all the 6 verification compounds). In addition, this QSRR model was compared with linear solvation energy relationship ( LSER) involved in different descriptors of molecular structure, showing no differences. The QSRR model was applied to measure Kow of 11 naphthalenes and anthraquinones, and the predicted data were compared with Shake-flask method (SFM) experimental ones, as well as calculated ones obtained by software. The results suggested that the proposed method for Kow determination in this work was more accurate, simple and fast. To the best of our knowledge, this is the first report on measuring Kow data for these compounds. The proposed strategy provides the possibility in determining Kow of lipophilic components in complex mixture more quickly and accurately by RP-HPLC.

Objective To analyze the clinical characteristics, risk factors, prevention, and treatments of de novo malignant tumors after orthotopic liver transplantation (OLT). Methods The clinical data of 4 patients with de novo malignant tumors out of the 726 patients undergoing OLT from October 2003 to December 2008 were analyzed. Results The morbidity of de novo malignant tumors after OLT was 0.6 % (4/726), and all of them were men. The 4 de novo malignant tumors were respectively diagnosed as acute myeloid leukaemia, gastric carcinoma, lung cancer, undifferentiated embryonal sarcoma of the liver. The age of patients during OLT was 42-57 years (mean 52 years). The age of patients' onset was 45-60 years (mean 53 years). The length was 6-38 months from liver transplantation to diagnosis of de novo malignant tumors (mean 31 months). All of the 4 patients died of tumor progression and multiple organ failure. The survival time was 12-48 months after OLT (mean 39.5 months), and that was 6-10 months after diagnosis of de novo malignant tumors (mean 8.5 months). Conclusion The incidence of de novo malignant tumors after OLT in China is lower than in abroad. The delayed diagnosis time is a main cause of death for patients with de novo malignant tumors after OLT. To think highly of precancerous lesions and high risk of factors, early diagnosis, and early treatment are the keys to improve the survival time.

Objective To investigate the indications, complication and survival of combined liver-kidney transplantation (CLKTs) after liver/kidney transplantation. Methods From Oct. 2003 to Dec. 2008, the clinical data of 3 patients who underwent CLKTs after liver/kidney transplantation were retrospectively followed up and literature was reviewed at our institution. The perioperative mortality, post-operative complications, survival were analyzed. Results The perioperative mortality of patients with CLKTs was 1/3. The postoperative complications: one patient with massive abdominal bleeding died of pulmonary infection, acute renal failure of graft, multiple organ failure on the 29th day after operation; 3 patients with pulmonary infection; no acute rejection of the graft. Two of 3 patients survived 56 months, 228 months from primary transplantation, respectively, while survived 40 months, 48 months from CLKTs, respectively. Conclusion CLKTs is only radical treatment method for patients with end-stage liver disease and end-stage kidney disease. CLKTs after liver/kidney transplantation were feasible.

Objective To investigate the occurrence and treatment of lamivudine resistance in immunocompromised chronic hepatitis B liver transplantation recipient. Methods From Oct 2003 to Mar 2005, 157 chronic hepatitis B liver recipients were analyzed retrospectively to investigate the occurrence and treatment of lamivudine resistant chronic hepatitis B. Results Ten (6. 37% ) cases developed resistance to lamivudine within 1 year after liver transplantation. These patients were treated subsequently with Adefovir dipivoxil or Entecavir. The mean reduction in HBV DNA levels at weeks 12,24,48 was(3. 85?0. 79)、(3. 27?0.84)、(3. 19?0.58) and 3,4,5 cases achieved HBV DNA

0.05). Compared with BHD group,HCC group had better liver function as assessed by Child-Pugh scores. Postoperatively, the period of artificial respiration was shorter in HCC group(P0.05). Elderly HCC patients meeting Milan criteria(n=12) had 1-,2-y overall and disease-free survival equivalent to patients exceeding Milan criteria (n=19).Conclusions Liver transplantation is safe and feasible in elderly patients. The prognosis of elderly patients with HCC after LT is comparable to those with benign hepatic disease. Milan criteria for selecting HCC patients for LT may be too restrictive and could be expanded in the elderly over sixty years of age.

Objective To evaluate the effect of liver transplantation(LT)on the prognosis in patients with intrahepatic cholangiocarcinoma(ICC).Methods A retrospective analysis was performed on 11 consecutive patients with ICC who underwent LT between October 2003 and November 2008 at our institution.The overall and disease-free survival rates were calculated by the Kaplan-Mayer method.Results The median survival time Was 9.0 months(2.5-53 months).The 1-,2-,3-and 4-year disease-free survival rate and overall survival rate of all the patients were 51.9%、51.9%、51.9%、51.9%and 50.5%、50.5%、50.5%、50.5%,respectively.The perioperative mortality and the recurrence rate were 0 and 43.5%,respectively.The survival rate and disease-free survival time of patients with recurrence were 2.5-10 months(mean 7.5 months)and 1-8 months(mean 3.8 months).Conclusions The prognosis of LT for ICC is rather poor.ICC patients with lymph node metastasis.vascular or bile duct invasion is contraindicated for LT.

AIM: To clone and express mouse telomerase reverse transcriptase(mTERT) cDNA and obtain eukaryotic expression vector.METHODS: The cDNA of mTERT was amplified by RT-PCR and PCR.After purification,the gene fragment was cloned into a vector PUC-19.The sequence of inserted mTERT gene fragment was also detected.RESULTS: The recombinant plasmid PUC-19-mTERT was constructed.Positive clones were screened and identified by PCR and digestion with restriction enzyme.The size of gene fragment was(3 369) bp and in accordance with the expected one.CONCLUSION: The mTERT cDNA was obtained and the recombinant eukaryotic expression vector was successfully constructed.The study lays foundation for DCs vaccine modified by mTERT gene for the treatment of tumor.

Objective To evaluate the role of hepatic artery interventional therapy for the prevention and treatment of biliary complications in orthotopic liver transplantation(OLT) with hepatic artery stricture (HAS). Methods We retrospectively analyzed biliary complications of 22 OLT recipients with HAS from Oct 2003 to Mar 2006 and evaluated the role of hepatic artery interventional therapy. Results One of three OLT recipients receiving early retrieval second transplants died of severe infection. The remaining 18 recipients were complicated with elevated?-glutamyl transferase and alkaline phosphatase, among them eleven (61. 1%) developed biliary stricture(BS) ,1(5. 6%) suffered from biliary leakage. Six (50%) of the 12 patients receiving hepatic artery interventional therapy developed BS later which was ameliorated by biliary interventional treatment. One of 2 patients receiving no hepatic artery interventional therapy developed BS which was cured by conservative treatment. None of the 4 patients receiving hepatic artery interventional therapy after the establishment of BS was cured and 3 (3/4) were improved and 1 (1/4) continued to deteriorate after hepatic artery and biliary interventional treatment. Conclusions Patients with HAS after OLT have a high rate of biliary complications. The result of hepatic artery interventional therapy to prevent and treat biliary complications of the patients with HAS is not satisfactory.

Objective: To understand the status of awarences and the influencing factors of food safety among medical students in Shangdong Province,and to provide a reference for improving a healthy eating habit among students on their knowledge about food safety,attitude and behavior. Methods: A total of 2 322 students from 2 medical colleges and universities in Shandong province selected through stratified cluster sampling were investigated with questionnaires. Results: Univariate analysis of variance showed that food safety knowledge differed by gender, grade, major, origin of student, whether learned nutrition knowledge, monthly cost on food (&chi;2/H=20.48, 128.02, 98.61, 36.50, 77.60, 171.03,P<0.01). In multiple Logistic regression analysis, results showed that gender, major,origin of student, monthly cost on food and the attention of food affect college students’ food safety awareness (P<0.05). Conclusion Food safety awareness among medical students in Shandong Province is relatively high but varies by multiple factors. It is necessary to improve food safety awareness of medical students through various channels.

Objective: To investigate the prevalence and influencing factors of suicidal ideation and the effects of daily stress and positive mental health on suicidal ideation among college freshmen in Wuhan. This study aims to provide a scientific basis for mental health improvement and suicide prevention among college students from the perspective of positive psychology. Methods: In December 2020, a convenient sampling method was used to select 2 592 freshmen from three universities in Wuhan. Demographic information, suicidal ideation, positive mental health, and daily stress were assessed. T test and Logistic regression analysis were used to analyze the status and influencing factors of suicidal ideation among college freshmen. Results: The one year prevalence of suicidal ideation was 27.5%. Freshmen with suicidal ideation had higher daily stress scores and daily stress scores in different domains than freshmen without suicidal ideation( t =-13.00--4.68)， the positive mental health scores of freshmen with suicidal ideation were lower than freshmen without suicidal ideation ( t =17.14， P <0.01). Female ( OR=1.72, 95%CI =1.44-2.05), the higher education level of the mother (OR=1.27, 95%CI=1.05-1.53) and total experience of daily stress ( OR=1.11, 95%CI =1.09- 1.13 ) were associated with risk of oneyear suicidal ideation. Positive mental health was negatively associated with suicidal ideation ( OR=0.88, 95%CI=0.87-0.90, P <0.01) and had a moderating effect on the association between daily stress and suicidal ideation. Conclusion Suicidal ideation among college freshmen is closely related to daily stress and positive mental health. It is necessary to pay close attention to daily stress of freshmen and reduce suicidal ideation by improving positive mental health.