[Objective] To conduct a retrospective statistical comparison of alanine aminotransferase (ALT) test values in blood donors prior to blood collection, aiming to analyze the objective characteristics of the population with elevated ALT levels (ALT>50 U/L) and provide reference data for adjusting the screening eligibility threshold for ALT. [Methods] The preliminary ALT screening data of 30 341 blood donor samples collected prior to blood donation from three smart blood donation sites at the Shenzhen Blood Center between 2022 and 2023 were extracted and compared with data from a health examination department of a tertiary hospital in Shenzhen (representing the general population, n=24 906). Both datasets were categorized and statistically described. A retrospective analysis was conducted to examine the associations between ALT test results and factors such as donors' gender, age, ethnicity, donation site, donation season, and frequency of blood donation. [Results] The ALT levels in both blood donors and the general population were non-normally distributed. The 95th percentile of ALT values was calculated as 61.4 U/L (male: 67.8 U/L, female: 39.3 U/L) for blood donors and 58.1 U/L (male: 63.7 U/L, female: 51.2 U/L) for the general population. The non-compliance rates (ALT>50 U/L) were 7.65% (2 321/30 341) in blood donors and 7.08% (1 763/24 906) in the general population. There were significant differences (P<0.05) in the ALT failure rate among blood donors based on gender, age, and donation site, but no significant differences (P>0.05) during the blood donation season. There was no statistically significant difference (P>0.05) in the positive rates of four serological markers (HBsAg, anti HCV, HIV Ag/Ab, anti TP) for blood screening pathogens between ALT unqualified and qualified individuals (2.05% vs 1.5%). If the ALT qualification threshold was raised from 50 U/L to 90 U/L, the non qualification rates of male and female blood donors would decrease from 9.82% (2 074/21 125) to 2.23% (471/21 125) and from 2.70% (249/9 216) to 0.75% (69/9 216), respectively. Among the 154 blood donors who donated blood more than 3 times, 88.31% of the 248 ALT test results were in the range of 50-90 U/L. Among them, 9 cases had ALT>130 U/L, and ALT was converted to qualified in subsequent blood donations. [Conclusion] There are differences in the ALT failure rate among blood donors of different genders and ages, and different blood donation sites and operators can also affect the ALT detection values of blood donors. The vast majority of blood donors with ALT failure are caused by transient and non pathological factors. With the widespread use of blood virus nucleic acid testing, appropriately increasing the ALT qualification threshold for blood donors can expand the qualified population and alleviate the shortage of blood sources, and the risk of blood safety will not increase.

[Objective] To investigate the factors associated with alanine aminotransferase (ALT) abnormalities in multi-ethnic blood donors across five Zang autonomous prefectures in the plateau regions of Qinghai Province, and to provide evidence for ensuring blood safety and formulating screening strategies. [Methods] A retrospective analysis was performed on the ALT abnormal test results of blood donors in the Zang autonomous prefectures of Qinghai from 2022 to 2024. The correlations between ALT levels and factors including gender, age, altitude, and infectious markers were investigated. [Results] The overall ALT unqualified rate among blood donors in this region was 9.01%. Significant differences in ALT levels were observed across genders and age groups (P<0.05). Variations in ALT abnormality rates were also noted among different plateau regions (P<0.05). Overall, ALT values exhibited an increasing trend with rising altitude. The average ALT unqualified rates were 11.19% in Zang donors, 7.96% in Han donors, and 4.79% in donors from other ethnic groups (P<0.05). No statistically significant association was observed between ALT abnormality and the presence of HBV/HCV infectious markers (P>0.05). [Conclusion] In the plateau areas of Qinghai, multi-ethnic blood donors have a relatively high ALT levels and ALT unqualified rates, showing distinct regional characteristics. ALT elevation in voluntary blood donors is related to non-pathological factors such as gender, age, and dietary habits, but not to infectious indicators.

Objective　To identify the clinical characteristics of a case of abdominal multiple cystic echinococcosis in Shenzhen City, Guangdong Province, and to characterize the molecular biology of pathogen, in order to provide a basis for control and prevention of echinococcosis. Methods　Clinical and epidemiological data of 1 case of echinococcosis in Shenzhen City in January 2024 were collected. The pathological sections of the cyst tissue removed by surgery were examined by microscopy after staining. Nucleic acids were extracted from cyst tissue samples, and the ND1 and Cox1 gene sequences were amplified and sequenced by PCR. Sequence comparison and phylogenetic tree analysis were performed using Mega X, BLAST and other software. Results　The patient, male, 29 years old, a resident of Nyerong County, Nagqu City, Xizang Autonomous Region, had a history of exposure to domestic dogs and hepatic echinococcosis. Imaging showed abdominal multiple placeholder, consider echinococcosis recurrence; 12 pieces of cystic lesions from different parts of the abdominal cavity were surgically removed, and the pathological sections of cystic tissues showed cuticle layer, germinal layer, protoscolex of echinococcosis. PCR amplification of the specific genes ND1 and Cox1 were positive, and the amplified fragments were about 510 bp and 285 bp, respectively. Sequence comparison and phylogenetic tree analysis results showed that the homology between the sequences in this study and the ND1 gene of Echinococcus granulosus type G1 (JX217890.1, Qinghai), and Cox1 gene (MH050610.1, Xizang) in the GenBank database was 99%. It is closely related to the epidemic strains of Echinococcus granulosus in Xizang, Qinghai and Xinjiang in the phylogenetic tree, and is in the same evolutionary branch (type G1). Conclusion　The patient was an imported case of abdominal multiple cystic echinococcosis, and the genotype was G1, with a high probability that the infection originated in Xizang. It is recommended to enhance the surveillance and management of echinococcosis in non-endemic areas, and to strengthen the inspection and quarantine of livestock and agricultural by-products imported from endemic areas to prevent the spread of echinococcosis.

OBJECTIVE To explore the improvement effect and mechanism of salidroside on radiation-induced parotid gland injury in rats. METHODS Rats were randomly assigned into normal group， radiation group， salidroside low-dose （salidroside-L， 50 mg/kg） group， salidroside high-dose （salidroside-H， 100 mg/kg） group， and salidroside-H+inhibitor （100 mg/kg salidroside+0.1 µmol/kg H-89） group， with 10 rats in each group. Except for the normal group， rats in the other groups were subjected to radiation exposure to establish a model of radiation-induced parotid gland injury. Rats in each group were intraperitoneally injected with the corresponding drug or normal saline， once a day， for 40 consecutive days. After the last administration， the levels of reactive oxygen species （ROS）， cyclic adenosine monophosphate （cAMP）， superoxide dismutase （SOD）， and amylase in serum were detected； the pathological changes of parotid gland tissue were observed； the apoptosis rate of parotid gland tissue cells， the expression levels of B-cell lymphoma-2 （Bcl-2） and its associated X protein （Bax）， mRNA expression levels of interleukin-6 （IL- 6） and tumor necrosis factor-α （TNF-α）， the protein expression levels of type Ⅲ collagen （Col Ⅲ）， vasoactive intestinal peptide （VIP）， and the phosphorylation level of protein kinase A （PKA） in parotid gland tissue were determined. RESULTS Compared with normal group， the levels of ROS， amylase， apoptosis rate， Bax expression level， mRNA expression levels of IL-6 and TNF- α， and protein expression level of Col Ⅲ in the radiation group were significantly increased， while the levels of cAMP， SOD， Bcl-2 expression level， VIP protein expression level and PKA phosphorylation level were significantly decreased （P＜0.05）. Compared with radiation group， the above indicators in the salidroside-L group and salidroside-H group were significantly improved （P＜0.05）， and the improvement in the salidroside-H group was more significant （P＜0.05）； inhibitor H-89 significantly reversed the changes in the above indicators of the salidroside-H group （P＜0.05）. CONCLUSIONS Salidroside can effectively alleviate radiation-induced parotid gland injury in rats， and its mechanism may be related to the activation of the VIP-cAMP pathway.

The utilization of optimal orthodontic force is crucial to prevent undesirable side effects and ensure efficient tooth movement during orthodontic treatment.However,the sensitivity of existing detection techniques is not sufficient,and the criteria for evaluating optimal force have not been yet established.Here,by employing 3D finite element analysis methodology,we found that the apical distal region(A-D region)of mesial roots is particularly sensitive to orthodontic force in rats.Tartrate-resistant acidic phosphatase(TRAP)-positive osteoclasts began accumulating in the A-D region under the force of 40 grams(g),leading to alveolar bone resorption and tooth movement.When the force reached 80 g,TRAP-positive osteoclasts started appearing on the root surface in the A-D region.Additionally,micro-computed tomography revealed a significant root resorption at 80 g.Notably,the A-D region was identified as a major contributor to whole root resorption.It was determined that 40 g is the minimum effective force for tooth movement with minimal side effects according to the analysis of tooth movement,inclination,and hyalinization.These findings suggest that the A-D region with its changes on the root surface is an important consideration and sensitive indicator when evaluating orthodontic forces for a rat model.Collectively,our investigations into this region would aid in offering valuable implications for preventing and minimizing root resorption during patients'orthodontic treatment.

Objective To find out the prevalence of antiretroviral therapy(ART)drugs among treponema pallidum(TP)antibody(anti-TP)positive blood donors in Shenzhen,and to assess the blood safety risks brought about by the new trends of human immunodeficiency virus(HIV)diagnosis and treatment.Methods A stratified random sampling method was used to select 60 repeat blood donors(negative control group)who passed blood screening in Shenzhen from March 2019 to January 2023,and 3 people who regularly took known ART drugs were named positive control group,358 anti-TP positive/anti-HIV negative blood do-nors were named experimental group 1,20 anti-TP positive/anti-HIV positive blood donors were named ex-perimental group 2.The liquid chromatography-mass spectrometry(HPLC-MS/MS)was applied to detect the concentration of 8 ART drugs in plasma samples of each group,and the use of ART drugs was analyzed.Re-sults After the positive control group's plasma was diluted with a 1:6 dilution mixture,the ART drugs could still be detected.The positive mixed plasma samples of 1:6 people in Group 1 and Group 2 were split and validation,one ART drug positive sample was detected in Group 2,which was positive for anti-HIV,pro-tein immunoblotting,and HIV RNA.The detection rate of ART drugs in anti-TP positive blood donors was 0.26％,0.00％in Group 1 and 4.00％in Group 2.Conclusion The use of ART drugs has been found among anti-TP positive blood donors in Shenzhen,and people with HIV infection and high-risk sexual behavior are more likely to use antiretroviral drugs.

Circulating tumor DNA (ctDNA) is cell-free DNA released by tumors or circulating tumor cells, containing abundant tumor-specific information that can serve as biomarkers for cancer early screening, monitoring, prognosis, and prediction of treatment response. This is particularly attractive in the field of gastric cancer, where high-quality screening, monitoring, and prediction methods are currently lacking. Gastric cancer exhibits significant tumor heterogeneity, with large differences in genetic and epigenetic characteristics among different subgroups. Methylated ctDNA has high sensitivity and specificity, which can help clarify tumor genotyping and facilitate the formulation of precise diagnostic and therapeutic strategies. Furthermore, numerous studies have confirmed the unique advantages of methylated DNA in predicting treatment response, adjuvant therapy, and drug resistance assessment, which may be used in the future to enhance the efficacy of chemotherapy regimens and improve patient chemotherapeutic response, and even treat multidrug resistance. However, there are several challenges associated with methylated ctDNA, such as low sensitivity and specificity at single-target sites, limited association between some gastric cancer subtypes and ctDNA, off-target risks, and the lack of large-scale and high-quality clinical research evidence. This review mainly summarizes current research on the methylation status of ctDNA in gastric cancer and connects these findings to early screening, recurrence monitoring, and potential treatment opportunities for gastric cancer. With advances in technology and the deepening of interdisciplinary research, ctDNA detection will reveal more disease information and become an essential foundation for gastric cancer research and precision medicine treatment.

Objective:To investigate the safety and therapeutic effect of split liver transplantation (SLT) in clinical application.Methods:This is a retrospective case-series study. The clinical data of 203 consecutive SLT, 79 living donor liver transplantation (LDLT) and 1 298 whole liver transplantation (WLT) performed at the Third Affiliated Hospital of Sun Yat-sen University from July 2014 to July 2023 were retrospectively analyzed. Two hundred and three SLT liver grafts were obtained from 109 donors. One hundred and twenty-seven grafts were generated by in vitro splitting and 76 grafts were generated by in vivo splitting. There were 90 adult recipients and 113 pediatric recipients. According to time, SLT patients were divided into two groups: the early SLT group (40 cases, from July 2014 to December 2017) and the mature SLT technology group (163 cases, from January 2018 to July 2023). The survival of each group was analyzed and the main factors affecting the survival rate of SLT were analyzed. The Kaplan-Meier method and Log-rank test were used for survival analysis.Results:The cumulative survival rates at 1-, 3-, and 5-year were 74.58%, 71.47%, and 71.47% in the early SLT group, and 88.03%, 87.23%, and 87.23% in the mature SLT group, respectively. Survival rates in the mature SLT group were significantly higher than those in the early SLT group ( χ2=5.560, P=0.018). The cumulative survival rates at 1-, 3- and 5-year were 93.41%, 93.41%, 89.95% in the LDLT group and 87.38%, 81.98%, 77.04% in the WLT group, respectively. There was no significant difference among the mature SLT group, the LDLT group and the WLT group ( χ2=4.016, P=0.134). Abdominal hemorrhage, infection, primary liver graft nonfunction,and portal vein thrombosis were the main causes of early postoperative death. Conclusion:SLT can achieve results comparable to those of WLT and LDLT in mature technology liver transplant centers, but it needs to go through a certain time learning curve.

Circulating tumor DNA (ctDNA) is cell-free DNA released by tumors or circulating tumor cells, containing abundant tumor-specific information that can serve as biomarkers for cancer early screening, monitoring, prognosis, and prediction of treatment response. This is particularly attractive in the field of gastric cancer, where high-quality screening, monitoring, and prediction methods are currently lacking. Gastric cancer exhibits significant tumor heterogeneity, with large differences in genetic and epigenetic characteristics among different subgroups. Methylated ctDNA has high sensitivity and specificity, which can help clarify tumor genotyping and facilitate the formulation of precise diagnostic and therapeutic strategies. Furthermore, numerous studies have confirmed the unique advantages of methylated DNA in predicting treatment response, adjuvant therapy, and drug resistance assessment, which may be used in the future to enhance the efficacy of chemotherapy regimens and improve patient chemotherapeutic response, and even treat multidrug resistance. However, there are several challenges associated with methylated ctDNA, such as low sensitivity and specificity at single-target sites, limited association between some gastric cancer subtypes and ctDNA, off-target risks, and the lack of large-scale and high-quality clinical research evidence. This review mainly summarizes current research on the methylation status of ctDNA in gastric cancer and connects these findings to early screening, recurrence monitoring, and potential treatment opportunities for gastric cancer. With advances in technology and the deepening of interdisciplinary research, ctDNA detection will reveal more disease information and become an essential foundation for gastric cancer research and precision medicine treatment.

Objective:To establish a high performance liquid chromatography method for the simultaneous determination of dimethyl oxalate (DMO) and diethyl oxalate (DEO) in workplace air.Methods:From January 2022 to January 2023, air samples were collected by silica gel tubes, desorbed by acetonitrile, separated by C18 chromatographic column, detected by photo-array detector, and retention time was used to characterize and peak area was used to quantify at 210 nm wavelength.Results:The linear relationships of DMO and DEO were good, r>0.999. The detection limits of DMO and DEO were 0.39 and 0.52 μg/ml, respectively. The quantitative limit was 1.28 μg/ml for DMO and 1.72 μg/ml for DEO. Average desorption efficiency for DMO was 82.40%-92.72%, and DEO was 94.13%-97.69%. The intra-assay precision of DMO was 1.87%-6.18%, and DEO was 2.25%-3.31%. Inter-assay precision of DMO was 3.29%-5.73%, and DEO was 1.38%-2.94%. Average sampling efficiencies were 100% for both DMO and DEO. Breakthrough capacity of DMO was 37.61 mg (200 mg solid adsorbent), DEO was >28.11 mg (200 mg solid adsorbent). Samples should be stored at 4 ℃ for at least 7 days. Conclusion:This method is easy to operate and has strong practicability. All indicators meet the requirements of the specification, and it is suitable for the simultaneous determination of DMO and DEO in the workplace air.