Liver cancer is one of the most common malignant tumors worldwide. Currently, the available treatment methods cannot fully control its recurrence and mortality rate. Establishing appropriate animal models for liver cancer is crucial for developing new treatment technologies and strategies. The patient-derived xenograft (PDX) model preserves the tumor's microenvironment and heterogeneity, which makes it advantageous for biological research, drug evaluation, personalized medicine, and other purposes. This article reviews the development, preparation techniques, application fields, and challenges of PDX models in liver cancer, providing insights for the research and exploration of PDX models in diagnostic and therapeutic strategies of liver cancer.
Liver Neoplasms/drug therapy* ; Animals ; Humans ; Xenograft Model Antitumor Assays/methods* ; Mice ; Disease Models, Animal

Objective:To explore the relationship between hemoglobin variability (Hb-var) and risk of all-cause death and cardiovascular death in patients with peritoneal dialysis (PD), and to provide basis for reducing the risk of death in PD patients.Methods:It was a multicenter retrospective cohort study. The clinical data of regular PD patients from Nanfang Hospital of Southern Medical University, Shunde Hospital of Southern Medical University, Foshan First People's Hospital and Ganzhou People's Hospital from July 1, 2008 to December 31, 2019 were collected. Hb-var was calculated based on hemoglobin at baseline before PD and in the first year after PD. The patients were divided into low Hb-var group, moderate Hb-var group and high Hb-var group according to the tertiles of first year Hb-var, and the differences of baseline clinical data among three groups were compared. Follow-up endpoints included death, transfer to hemodialysis, transfer to kidney transplantation, transfer to other centers, loss of follow-up, or on December 31, 2021. Cox regression analysis model was used to analyze the association of the first-year Hb-var with all-cause death and cardiovascular death. Fine-Gray competitive risk regression model was used to evaluate the impact of competitive events on mortality risk.Results:A total of 1 562 patients with PD were included in the study, aged (47.6±13.8) years old, with 821 males (52.6%) and baseline hemoglobin of 81 (69, 94) g/L. Hb-var in the first year of PD was 26.6 (16.7, 40.3) g/L. There were statistically significant differences in age, body mass index, serum albumin, hemoglobin, serum creatinine, serum calcium, serum phosphorus, intact parathyroid hormone and the proportion of renin-angiotensin system inhibitors among low Hb-var group (<20.0 g/L), moderate Hb-var group (20.0-35.5 g/L) and high Hb-var group (≥35.5 g/L, all P<0.05). The follow-up time was 33 (19, 51) months, and 208 patients (13.3%) died, among which 111 patients (53.4%) died of cardiovascular death. Multivariate Cox regression analysis showed that the higher Hb-var in the first year, the lower the risk of all-cause death ( HR=0.98, 95% CI 0.97-0.99, P=0.018) and cardiovascular death ( HR=0.98, 95% CI 0.97-0.99, P=0.041) in PD patients. Compared with low Hb-var group, the risk of all-cause death ( HR=0.56, 95% CI 0.37-0.82, P=0.003) and cardiovascular death ( HR=0.54, 95% CI 0.31-0.95, P=0.032) was lowest in the high Hb-var group. The competitive risk regression model analysis showed that Hb-var in the first year was still negatively correlated with the risk of all-cause death ( HR=0.98, 95% CI 0.97-0.99, P=0.041) and cardiovascular death ( HR=0.98, 95% CI 0.97-0.99, P=0.039). Conclusion:High Hb-var in the first year is associated with low risk of all-cause death and cardiovascular death in PD patients with severe anemia at baseline.

Objective: To investigate the infection sources and the transmission chains of three outbreaks caused by 2019-nCoV Omicron variant possibly spread through cross-border logistics in Beijing. Methods: Epidemiological investigation and big data were used to identify the exposure points of the cases. Close contacts were traced from the exposure points, and the cases' and environmental samples were collected for nucleic acid tests. Positive samples were analyzed by gene sequencing. Results: The Omicron variant causing 3 outbreaks in Beijing from January to April, 2022 belonged to BA.1, BA.1.1 and BA.2. The outbreaks lasted for 8, 12 and 8 days respectively, and 6, 42 and 32 cases infected with 2019-nCoV were reported respectively. International mail might be the infection source for 1 outbreak, and imported clothes might be the infection sources for another 2 outbreaks. The interval between the shipment start time of the imported goods and the infection time of the index case was 3-4 days. The mean incubation period (Q₁, Q₃) was 3 (2,4) days and the mean serial interval (Q₁, Q₃) was 3 (2,4)days. Conclusions: The 3 outbreaks highlighted the risk of infection by Omicron variant from international logistics-related imported goods at normal temperature. Omicron variant has stronger transmissibility, indicating that rapid epidemiological investigation and strict management are needed.
Humans ; Beijing ; SARS-CoV-2 ; COVID-19 ; Disease Outbreaks ; China/epidemiology*

Objective: To investigate the epidemiological characteristics and the transmission chain of a family clustering of COVID-19 cases caused by severe acute respiratory 2019-nCoV Delta variant in Changping district of Beijing. Methods: Epidemiological investigation was conducted and big data were used to reveal the exposure history of the cases. Close contacts were screened according to the investigation results, and human and environmental samples were collected for nucleic acid tests. Positive samples were analyzed by gene sequencing. Results: On November 1, 2021, a total of 5 COVID-19 cases caused by 2019-nCoV Delta variant were reported in a family detected through active screening. The infection source was a person in the same designated isolation hotel where the first case of the family cluster was isolated from 22 to 27, October. The first case was possibly infected through aerosol particles in the ventilation duct system of the isolation hotel. After the isolation discharge on October 27, and the first case caused secondary infections of four family members while living together from October 27 to November 1, 2021. Conclusion: 2019-nCoV Delta variant is prone to cause family cluster, and close attention needs to be paid to virus transmission through ventilation duct system in isolation hotels.
Aerosols ; COVID-19 ; Epidemics ; Humans ; SARS-CoV-2

Objective:To explore the relationship between low serum albumin levels and its duration on first episode of peritonitis in peritoneal dialysis (PD) patients.Methods:PD patients who were regularly followed up in the Pearl River Delta region from September 1, 2000 to July 6, 2021 in Shunde Hospital of Southern Medical University, Nanfang Hospital of Southern Medical University, and Foshan First People′s Hospital were retrospectively selected. The patients were divided into low serum albumin group (LSA group, mean albumin<35 g/L), moderate serum albumin group (MSA group, 35 g/L≤mean albumin<40 g/L) and high serum albumin group (HSA group, mean albumin≥40 g/L) according to the mean albumin of the patients, and the differences among the three groups were compared. The Kaplan-Meier survival analysis method was used to compare the risk of peritonitis events in different mean albumin groups and different durations of hypoalbuminemia. The multivariate Cox regression model was used to analyze the relationship between serum albumin levels and duration of hypoalbuminemia and new-onset peritonitis.Results:A total of 1 853 PD patients were included in this study, aged (49.72±15.34) years, and 1 036(55.9%) males. There were 551 patients (29.7%) in the LSA group, 920 patients (49.7%) in the MSA group, and 382 patients (20.6%) in the HSA group. The median follow-up was 37 (15, 66) months and there were 508 patients (27.4%) with new-onset peritonitis during the follow-up. Compared with the LSA group, the incidence of new peritonitis in the MSA group and HSA group was lower ( χ2=14.053, P<0.001; χ2=21.857, P<0.001), but there was no significant difference in the incidence of new peritonitis between the HSA group and MSA group. The Kaplan-Meier survival analysis showed that the cumulative incidence of peritonitis in the LSA group was significantly higher than that in the MSA group and HSA group (Log-rank χ2=22.128, P<0.001). Compared with PD patients with normal serum albumin, the patients with longer duration of hypoalbuminemia tended to have a higher incidence of new peritonitis. Multivariate Cox regression analysis showed that the mean albumin<35 g/L (LSA group/MSA group, HR=1.495, 95% CI 1.198-1.866, P<0.001; LSA group/HSA group, HR=1.459, 95% CI 1.104-1.928, P=0.008) was an independent risk factor of new-onset peritonitis in PD patients and the prolongation of duration of hypoalbuminemia had a significantly higher risk of new-onset peritonitis ( HR=1.013, 95% CI 1.003-1.024, P=0.014). Conclusion:The mean albumin<35 g/L and prolong duration of hypoalbuminemia are independent risk factors of PD-related peritonitis in PD patients.

Objective: A method for the determination of acetochlor and its metabolites in urine by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was established. Methods: After cleaned-up by a HLB extraction cartridges, the urine was eluted with 1% acetic acid acetonitrile solution. The target compounds were separated by ACQUITY UPLC®HSS T3 Column (2.1 mm×100 mm×1.8 μm) by using 1% formic acid solution and acetonitrile as mobile phase with gradient elution program, and analyzed in positive electrospray ionization mode by liquid chromatography tandem mass spectrometry. Results: All the target compounds showed good linear relationships in the range of 1-50 μg/L, and the correlation coefficients (r) were higher than 0.997. The recoveries rates at three different spiked levels for all target compounds in blank matrices were 107.6%-129.1%, and the relative standard deviations (RSD) were 1.5%-9.9% (n=6) . The limits of detection and quantitation of the method were 0.04-0.11 μg/L and 0.15-0.42 μg/L, respectively, and target substances were detected in all urine samples from occupational exposure workers to acetochlor. Conclusion: This method is suitable for rapid screening and analysis of acetochlor and metabolites in urine with the advantages of accuracy, rapidity, simplicity, high sensitivity and good specificity.
Acetonitriles ; Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Humans ; Solid Phase Extraction ; Tandem Mass Spectrometry ; Toluidines

Aim To investigate the hepatotoxic effect of aqueous extract of fructus psoraleae (WEFP) on lipopolysaccharide (LPS)-induced hepatotoxicity in SD rats under immune stress and its mechanism. Methods SD rats were divided into control (CON), LPS, WEFP, LPS+WEFP group. The LPS and LPS+WEFP groups were injected with 4 mg·kg-1 LPS via tail vein; 2 h later, the rats in WEFP group and LPS+WEFP group received the WEFP (1.1 g·kg-1·d-1) by oral gavage for seven consecutive days. Different endpoints such as body weight, liver index, bile flow rate, serum biochemical, histopathological changes, inflammatory cytokines, protein and mRNA expression levels were determined to clarify the liver toxicity and mechanism of WEFP. Results Compared with the CON group, rats in the LPS group had no significant changes in body weight, liver coefficient, serum ALT, AST, and ALP liver injury indicators; mild steatosis in the liver of the rats in the WEFP group did not cause liver damage; for rats in the LPS+WEFP group, body weight and bile excretion decreased, liver coefficient, serum ALT, AST, ALP, TBA levels significantly increased, and IL-1 and TNF-α secretion in the liver increased; at the same time, the pathological changes such as inflammatory reaction, cholestasis, and steatosis appeared in liver, RhoA mRNA and protein expression increased, and TLR4 and ICAM-1 pro-inflammatory gene expression increased, leading to acute liver injury. Conclusions The non-hepatotoxic dose of LPS can cause the same dose of psoralen to show more obvious liver toxicity, leading to the body's immunospecific response. Psoralen can cause immune stress rats to activate the expression of RhoA and other pro-inflammatory genes, further aggravate the release of inflammatory factors,and promote inflammatory reaction damage to liver cells and intrahepatic bile duct tissues,leading to obstruction of bile acid efflux and causing special effects such as heterogeneous liver injury.

OBJECTIVES: To study the prognostic value of measurable residual disease (MRD) for childhood acute myeloid leukemia (AML) by analyzing MRD-guided risk stratification therapy. METHODS: A total of 93 children with AML were prospectively enrolled in this study. Chemotherapy with the 2015-AML-03 regimen was completed according to the risk stratification determined by genetic abnormality at initial diagnosis and MRD and bone marrow cytology after induction therapy I. Multiparameter flow cytometry was used to dynamically monitor MRD and analyze the prognostic effect of MRD on 3-year cumulative incidence of recurrence (CIR) rate, event-free survival (EFS) rate, and overall survival (OS) rate. RESULTS: The 93 children with AML had a 3-year CIR rate of 48%±6%, a median time to recurrence of 11 months (range 2-32 months), a 3-year OS rate of 65%±6%, and a 3-year EFS rate of 50%±5%. After induction therapy I and intensive therapy I, the MRD-positive children had a significantly higher 3-year CIR rate and significantly lower 3-year EFS and OS rates than the MRD-negative children ( CONCLUSIONS MRD has predictive value for the prognosis of children with AML. Based on the MRD-guided risk stratification therapy, reasonable application of chemotherapy may improve the overall prognosis of children with AML.
Child ; Disease Progression ; Flow Cytometry ; Humans ; Leukemia, Myeloid, Acute/drug therapy* ; Neoplasm, Residual ; Prognosis

Objective To investigate the correction between the levels of vascular endothelial growth factor (VEGF), serum amyloid A (SAA), hypersensitive C-reactive protein (hs-CRP) and acute cerebral infarction (ACI), and to provide the basis for the diagnosis and treatment of ACI.Methods A total of 76patients with ACI in the hospital from August to October 2017were selected as ACI group.In addition, 32healthy subjects underwent physical examination in the same period in this hospital were selected as negative control group (NC group).The levels of SAA and hs-CRP were detected by nephelometry, while the level of VEGF was measured by enzyme-linked immunosorbent assay (ELISA).The differences of detection indexes between two groups were compared, and the diagnostic value of each index and the combined test were evaluated with the Youden index.Results The levels of SAA, hs-CRP and VEGF in ACI group, were significantly higher than those of NC group (P＜0.01).The levels of VEGF was positively correlated with SAA and hs-CRP (r=0.434and0.631, P=0.000and 0.000).The optimal diagnostic critical points of VEGF, SAA and hs-CRP in the diagnosis of ACI were 161.93pg/mL, 3.81mg/L and 4.63mg/L, and the sensitivities were 93.55％, 65.91％and64.44％, the specificities were 60.00％, 93.75％and 90.32％, respectively.Combined detection with hs-CRP and VEGF was superior to single index detection and other joint detection.The sensitivity, specificity and Youden index of combined detection with hs-CRP and VEGF were 96.67％, 95.65％and 0.92respectively.Conclusion The levels of VEGF, SAA and hs-CRP increase in patients with ACI, and they play important roles in the diagnosis of ACI.VEGF are positively related to SAA and hs-CRP, and there may be an synergistic effect exist.VEGF may be involved in the pathological process of cerebral infarction.The combined detection of hs-CRP and VEGF is of high clinical value in the diagnosis of cerebral infarction.

Objective The implementation and prospect of excellent young scientists fund in the department of health sciences of national natural science of foundation of china were reviewed and discussed to propose suggestions for future development.Methods The applications and grants of excellent young scientists fund in health sciences field from 2012 to 2017 wereanalyzed among different medical branches,regions and supporting institutions.The age,gender,title and academic rank of both applicants and awardees were analyzed.Results The applications and grants of excellent young scientists fund vary greatly in the different branches of medical science,as well as in the different regions and supporting institutions.The person in charge of such projects has been better developed after being awarded.Conclusions The establishment and implementation of the excellent young scientists fund has promoted the growth of young medical scientists.