Objective To investigate the feasibility and accuracy of convolutional neural networks for automatically delineating the pancreatic cancer gross target volume(GTV)in pancreatic enhanced CT.Methods The localizable enhanced CT images of 114 patients with pancreatic cancer were retrospectively selected,in which the GTV was manually delineated using AccuContour.The imaging data were then import to AccuLearning and randomly divided as the training set,validation set and test set at a ratio of 8:1:1.Flex and Segresnet were used to train the automatic segmentation model,with each network structure trained continuously 3 times using fixed training parameters.The model was evaluated in terms of Dice similarity coefficient(DSC),95%Hausdorff distance(HD95),average symmetric surface distance(ASSD)and relative volume difference(RVD).Results In the model training phase,Flex-3 test results in Flex group were the worst,with a minimum DSC of 0.14%and an average DSC of 56.30%,while Flex-1 performed well,achieving a minimum DSC of 47.90%and an average DSC of 67.35%.Meanwhile,Segresnet-2 in Segresnet group had the worst test results,with a minimum DSC of 0.00%and an average DSC of 42.46%,while Segresnet-3 test results were better,with a minimum DSC of 42.65%and an average DSC of 63.28%.In the fixed testing phase,the best results among all were as follows:average DSC and RVD values of 63.88%and 29.41%in Segresnet-3 group,average ASSD value of 4.43 mm in Segresnet-2 group,and average HD95 value of 12.87 mm in Segresnet-1 group.Conclusion Both Flex and Segresnet architectures of convolutional neural network can be used for the automatic pancreatic tumor GTV segmentation training,with Segresnet performing better in comprehensive evaluation.

Objective To investigate the feasibility and accuracy of convolutional neural networks for automatically delineating the pancreatic cancer gross target volume(GTV)in pancreatic enhanced CT.Methods The localizable enhanced CT images of 114 patients with pancreatic cancer were retrospectively selected,in which the GTV was manually delineated using AccuContour.The imaging data were then import to AccuLearning and randomly divided as the training set,validation set and test set at a ratio of 8:1:1.Flex and Segresnet were used to train the automatic segmentation model,with each network structure trained continuously 3 times using fixed training parameters.The model was evaluated in terms of Dice similarity coefficient(DSC),95%Hausdorff distance(HD95),average symmetric surface distance(ASSD)and relative volume difference(RVD).Results In the model training phase,Flex-3 test results in Flex group were the worst,with a minimum DSC of 0.14%and an average DSC of 56.30%,while Flex-1 performed well,achieving a minimum DSC of 47.90%and an average DSC of 67.35%.Meanwhile,Segresnet-2 in Segresnet group had the worst test results,with a minimum DSC of 0.00%and an average DSC of 42.46%,while Segresnet-3 test results were better,with a minimum DSC of 42.65%and an average DSC of 63.28%.In the fixed testing phase,the best results among all were as follows:average DSC and RVD values of 63.88%and 29.41%in Segresnet-3 group,average ASSD value of 4.43 mm in Segresnet-2 group,and average HD95 value of 12.87 mm in Segresnet-1 group.Conclusion Both Flex and Segresnet architectures of convolutional neural network can be used for the automatic pancreatic tumor GTV segmentation training,with Segresnet performing better in comprehensive evaluation.

Background and aim:Few studies have reported hepatitis B surface antigen(HBsAg)kinetics after nucleos(t)ide analog(NA)discontinuation in patients with noncirrhotic chronic hepatitis B(CHB).The study specifically investigated long-term HBsAg kinetics after NA discontinuation. Methods:Between January 2014 to January 2024,this study prospectively enrolled 106 outpatients with noncirrhotic CHB who met the discontinuation criteria after NA consolidation treatment.Demographic,clinical,and laboratory data were collected and analyzed after NA discontinuation. Results:Ninety-six patients who finished 5 years of follow-up were included.HBsAg remained unde-tectable in 29 patients with end of treatment(EOT)HBsAg negativity.Among 67 patients with EOT HBsAg positivity,HBsAg seroclearance occurred in 12(17.9％)patients with an estimated annual inci-dence of HBsAg seroclearance of 3.6％.Patients with EOT HBsAg levels of ≤1000 IU/mL had a higher HBsAg seroclearance rate than those with EOT HBsAg levels of＞1000 IU/mL(33.3％vs.5.4％).The pro-portion of patients with HBsAg ≤1000 IU/mL increased during follow-up.Logistic regression analysis indicated that the EOT HBsAg level was an independent factor for HBsAg seroclearance and an HBsAg level decline exceeding 1 log10 IU/mL.The optimal EOT HBsAg cutoff for both HBsAg seroclearance and an HBsAg level decline exceeding 1 log10 IU/mL was 359 IU/mL. Conclusions:Patients with EOT HBsAg negativity experienced no relapse and maintained HBsAg sero-clearance during 5 years of follow-up after NA discontinuation.A higher HBsAg seroclearance rate can be obtained in patients with EOT HBsAg levels of ≤1000 IU/mL during 5 years of follow-up after NA discontinuation.Close monitoring and proper NA retreatment are recommended to guarantee the safety of NA discontinuation.

OBJECTIVE: To investigate the expression of RNA methyltransferase METTL14 in hepatocellular carcinoma (HCC) and its clinical significance. METHODS: Immunohistochemical staining was used to detect the expression of METTL14 in 147 pairs of HCC and adjacent hepatic tissues. According to the scores rated by pathologists, the 147 cases of HCC were divided into high and low METTL14 expression groups. The correlation between the expression of METTL14 and clinicopathological parameters was analyzed, and Kaplan-Meier method was used to analyze the relationship between the expression of METTL14 and the prognosis and survival (including the overall survival and disease-free survival) of the patients with HCC after operation. Univariate analysis and multivariate analysis were carried out to assess the impact of METTL14 expression level on the overall survival and tumor-free survival of the patients after operation using a COX regression model and explore whether METTL14 expression level is an independent prognostic risk factor of the postoperative patients. RESULTS: The expression of METTL14 was significantly lower in HCC tissues than in the adjacent tissues ( < 0.001). METTL14 expression in HCC tissues was significantly correlated with the tumor size (=0.044) and TNM stage (=0.046). A low expression of METTL14 in HCC tissues was significantly correlated with a poor prognosis and a significantly shortened overall survival time and disease-free survival time of the patients ( < 0.05), and was an independent risk factor affecting the overall survival and disease-free survival of HCC patients. CONCLUSIONS METTL14 may be a new prognostic marker for patients with HCC after hepatectomy.
Biomarkers, Tumor ; Carcinoma, Hepatocellular ; Disease-Free Survival ; Hepatectomy ; Humans ; Kaplan-Meier Estimate ; Liver Neoplasms ; Methyltransferases ; Prognosis

Objective: To investigate the effects of direct-acting antiviral agents (DAA) therapy on the frequency of myeloid-derived suppressor cells (MDSC) and their subset of monocytic myeloid-derived suppressor cells (M-MDSC) in chronic hepatitis C (CHC) patients. Methods: A total of 32 treatment-naive CHC patients and 16 healthy controls were recruited at Third Affiliated Hospital of Sun Yat-Sen University from June 2016 to June 2017. The peripheral blood mononuclear cells (PBMC) were separated from the peripheral blood of patients with CHC before DAA therapy, at four weeks after DAA therapy, at 12 weeks after DAA therapy and 12 weeks after the end of DAA therapy. The frequencies of MDSC and M-MDSC were detected by the flow cytometer. The t test, U test and chi-square test was employed to analyze the data. Results: All the 32 treatment-naive patients achieved the rapid virological response and no virological breakthrough was observed. Before DAA therapy, the frequency of MDSC in CHC patients was 2.18%, which was higher than healthy individuals (0.60%; Z=-4.593, P<0.01), and positively correlated with the plasma levels of hepatitis C virus (HCV) RNA (r=0.688, P<0.01) and aspartate aminotransferase (r=0.735, P<0.01). After four weeks of DAA therapy, the frequency of MDSC decreased significantly to 1.07%, with no statistical significance compared to the controls (Z=-1.221, P>0.05). However, at 12 weeks after DAA therapy, the MDSC frequency increased, with statically significance compared to the controls (1.64% vs 0.60%, Z=-3.117, P=0.002). At 12 weeks after the end of DAA therapy, the MDSC frequency had decreased to 1.29% again, with no statistical significance compared to the controls (Z=-1.387, P=0.664). The changes of M-MDSC frequency were slightly different. Before DAA therapy, the frequency of M-MDSC in CHC patients was higher compared to healthy controls (1.66% vs 0.81%, Z=-2.745, P<0.01). The frequencies of M-MDSC were 0.91%, 1.09% and 1.10% at four, 12 weeks after DAA and 12 weeks after the end of DAA therapy, respectively. The differences were not statistically significant compared to the controls (Z=-0.589, -1.028 and -0.486, respectively, all P>0.05). Conclusion Immune status of the peripheral MDSC and M-MDSC can return to normal after DAA therapy in CHC patients.

Objective To evaluate the effects of dexmedetomidine on the development of perioperative cardiovascular events in elderly patients.Methods Forty-eight patients of both sexes,aged 65-85 yr,with body mass index of 19.5-25.3 kg/m2,of American Society Anesthesiologists physical status Ⅱ or Ⅲ,scheduled for elective abdomninal or lower limb surgery under general anesthesia,were divided into 2 groups (n =24 each) using a random number table:general anesthesia group (group G) and dexmedetomidine plus general anesthesia group (group D).In group D,dexmedetomidine was intravenously infused in a loading dose of 0.25 μg/kg over 10 min and then continuously infused at 0.2 μg · kg-1 · h-1 until 30 min before the end of surgery.The equal volume of normal saline was intravenously infused instead in group G.At 1 day before surgery and 1 and 2 days after surgery,dynamic electrocardiogram was used to monitor heart rate variability including standard deviation of normal-to-normal intervals,standard deviation of the average 5-min normal-to-normal intervals,and root of the mean of the sum of the squares of differences between adjacent normal-to-normal intervals.The development of intraoperative cardiovascular events and requirement for vasoactive drugs were recorded,and the development of cardiovascular events within 2 days after surgery was also recorded.Results Compared with group G,standard deviation of normal-to-normal intervals and standard deviation of the average 5-min normal-to-normal intervals at 1 and 2 days after surgery and root of the mean of the sum of the squares of differences between adjacent normal-to-normal intervals at 2 days after surgery were significantly increased,the total incidence of intraoperative cardiovascular events and requirement for vasoactive drugs were decreased,and the total incidence of cardiovascular events within 2 days after surgery was decreased in group D (P ＜0.05).Conclusion Dexmedetomidine can reduce the development of perioperative cardiovascular events in elderly patients.