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Objective:To investigate the effect of radioactive 125I seed on angiogenesis of subcutaneously transplanted hepatocellular carcinoma in nude mice and underlying mechanism. Methods:The subcutaneous transplanted tumor model of human hepatocellular carcinoma Huh7 cells was established in nude mice. Twelve nude mice were randomly divided into observation group and control group with 6 mice in each group. The 125I seed with activity of 2.96×10 7Bq was implanted into the transplanted tumor of observation group and another with 0 Bq as control group, respectively. The volume of the transplanted tumor was measured every 4 d and the growth curve of the tumor was recorded. The microvessel density (MVD) of the transplanted tumor was evaluated by immunohistochemical detection of CD31. VEGF-A and HIF-1α protein and mRNA were detected by immunohistochemistry and RT-PCR, respectively. Results:The growth rate of tumor in the observation group was slower than that in the control group, and the difference of tumor volume between two groups at 12 d after 125I seed implantation was significantly different( t=3.167, P<0.05). At 28 d after transplantation, the tumor volumes of control and observation group approached to (963.61 ± 89.56) mm 3and (602.10±75.98) mm 3, respectively. The MVD of the observation group was significantly lower than that of the control group ( t=6.361, P<0.05). The relative expression of VEGF-A and HIF-1α mRNA in the observation group was significantly lower than that in the control group ( t=10.480, 6.414, P<0.05). Protein expression levels of VEGF-A and HIF-1α in the observation group were lower than those in the control group ( t=10.890, 12.250, P<0.05). Conclusions:Radioactive 125I seed can inhibit the growth of HCC xenografts by reducing tumor microvessels, which may be related to the decrease of VEGF-A and HIF-1α expression.
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Objective:To compare the differences in dosimetric parameters of target areas between 125I seed implantation with degradable catheters and by hand under the assistance of a real-time intraoperative treatment planning system (TPS). Methods:Forty-two simulated lesions were divided into a degradable catheter group and a free-hand group, with twenty-one lesions in each group. 125I seeds were implanted according to the TPS.The pre-plan and post-implant dosimetric parameters were collected, including the minimum dose ( Dmin), maximum dose ( Dmax), mean dose ( Dmean), conformal index (CI), external index (EI), homogeneity index (HI), minimum prescription dose delivered to 90% of the target volume ( D90), and the mean percentage of volume receiving 90% of the prescription doses ( V90). The Bland-Altman method was employed to analyze the consistency of pre-plan and post-implant dosimetric parameters and the Wilcoxon rank-sum test was used for the comparison of the two groups. Results:According to the Bland-Altman analysis, the dosimetric parameters of the two groups were all in agreement before and after seed implantation except for the Dmin and V90 of the free-hand group.Furthermore, the degradable catheter group had smaller error ranges of Dmax ( Z=-3.824, P<0.005), CI ( Z=-1.962, P<0.005), HI ( Z=-2.352, P<0.005), D90 ( Z=-2.453, P<0.005), and V90 ( Z=-3.159, P<0.005). Conclusions:The dosimetric parameters of 125I seed implantation with degradable catheters under the assistance of real-time TPS have good pre-plan and post-implant consistency and smaller error ranges.
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Objective@#To investigate the level of the core knowledge and related factors of cancer prevention and treatment among residents in the upper gastrointestinal cancer screening areas of Sichuan Province in 2018. @*Methods@#From April to May 2018, a total of 1 386 residents from Chaotian District of Guangyuan, Enyang District of Bazhong, Nanjiang County of Bazhong, Cangxi County of Guangyuan, Shehong County of Suining, Yilong County of Nanchong, Xichong County of Nanchong and Xuanhan County of Dazhou were recruited in this study. A questionnaire survey was conducted to collect basic demographic characteristics and the knowledge of cancer prevention and treatment. The level of the core knowledge of cancer prevention and treatment of different population was analyzed. A multivariate linear regression model was performed to analyze the related factors. @*Results@#In total, 80.9% (1 120) of all subjects was 25-64 years old and 48.0% (665) were male. The total number of questions answered by the subjects was 18 018, of which 12 147 were known, and the overall awareness rate among the respondents was 67.42%. The female respondents, respondentsaged 65 years old and over, with junior college education or above, and worked in government institutions had a good performance of the core knowledge (P<0.05), about 70.11% (6 571/9 373), 69.23% (387/559), 76.05% (6 327/8 320), and 77.09% (5 602/7 267) respectively. The results of multivariate linear regression showed that the older the age [β=0.871 (95%CI: 0.623-1.119)], the higher the educational level [β=0.741 (95%CI: 0.540-0.943)], the more questions respondents could know; compared with the workers in government organization and institution, workers in enterprise [β=-2.913 (95%CI:-3.499--2.327)], farming workers [β=-0.635 (95%CI:-1.175--0.095)] and other occupation people [β=-1.126 (95%CI:-1.663--0.589)] could know fewer questions. @*Conclusion@#In 2018, the level of the core knowledge of cancer prevention and treatment among residents in upper gastrointestinal cancer screening areas of Sichuan Province was relatively high. Age, education level and occupation were relevant factors.
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Objective@#To investigate the safety and efficacy of irreversible electroporation (IRE) hepatic ablation with high-frequency bipolar pulse in swine.@*Methods@#The experimental study was conducted. A total of 18 swines of either gender, aged (6.8+ 0.8)months with a range of 5.5-8.0 months, were collected from Animal Laboratory Center of Army Medical University. were randomly divided into 15 in experimental group and 3 in control group. The swines in experimental group underwent IRE hepatic ablation with high-frequency bipolar pulse, and 3 swines were chose randomly and underwent enhanced CT examination immediately after ablation, and at 3, 7, 14, and 28 days after ablation. The liver tissues were taken for histopathological examination. The swines in the control group underwent IRE hepatic ablation with high-frequency monopolar burst, and was performed enhanced CT examination at 3 days after ablation. Liver tissues were taken for histopathological examination. Observation indicators: (1) comparison of muscle contraction of siwnes between two groups; (2) imaging performance on enhanced CT after IRE ablation in the experimental group; (3) hepatic histopathological findings after IRE ablation in the experimental group; (4) comparison of apoptotic index in the ablation zone between two groups. The measurement data with normal distribution were expressed as Mean±SD, and comparison between groups was performed by the independent sample t test.@*Results@#(1) Comparison of muscle contraction between two groups: swines in both groups underwent ablation successfully. The degree of muscle contraction was (9.8±0.4)m/s2 and (48.6±0.5)m/s2 in the experimental group and in the control group, respectively, showing statistically significant difference between the two groups (t=-163.50, P<0.05). (2) Imaging performance on enhanced CT after IRE ablation in the experimental group: the enhanced CT examination of swines immediately after IRE ablation showed a low-density shadow and clear boundary in the ablation zone. There was no obvious abnormality in the ablation zone and its adjacent large vessels. No serious complications occurred after the ablation. The boundary between the ablation zone and the normal liver tissue of the experimental group gradually became blurred over time, and the ablation zone was gradually replaced by normal liver tissue. The ablation zone at the 28 days after ablation was significantly reduced or even disappeared on imaging of enhanced CT examination.The maximum diameter of the ablation zone was (1.81±0.17)cm immediately after ablation, (1.75±0.19)cm at the 3 days after ablation, (1.32±0.22)cm at the 7 days after ablation, (0.65±0.14)cm at the 14 days after ablation, (0.28±0.10)cm at the 28 days after ablation, respectively. (3) Hepatic histopathological findings after IRE ablation in the experimental group: the HE staining of ablated tissue immediately after ablation showed that the cells in the ablation zone were swollen, arranged disorderly, and bleeding was observed around some of the needles.The bile ducts and blood vessels were intact in the ablation zone, and a large number of deeply stained nuclei were seen at 3 days after ablation, some of the nucleus and apoptotic bodies were partially dissolved or cleaved. A large number of inflammatory cell were infiltrated around the ablation zone. Intact vascular and biliary endothelial cells were observed by von Willebrand factor staining, a larger number of apoptotic cells with deeply stained nuclei in the ablation zone were observed by terminal-deoxynucleoitidyl transferase mediated nick end labeling staining, and partial deposited dark brown calcium salt was seen by Von Kossa staining. More newborn hepatocytes were observed growing from the periphery of the ablation zone to the center at the 7, 14, 28 days after ablation. Smooth muscle cell proliferation was observed at 14 and 28 days after ablation. The ablation zone was replaced by new cells on 28 days after ablation. (4) Comparison of apoptotic index in the ablation zone between two groups: the apoptotic index of the ablation zone was significantly higher in the experimental group than in the control group on the 3 days after operation (76.67%±0.04% vs. 64.03%±0.05%, t=4.79, P<0.05).@*Conclusion@#IRE hepatic ablation of swine using high-frequency bipolar pulse is safe and reliable, and it has more apoptotic cells than IRE ablation with high-frequency monopolar burst.
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Objective To investigate the safety and efficacy of irreversible electroporation (IRE) hepatic ablation with high-frequency bipolar pulse in swine.Methods The experimental study was conducted.A total of 18 swines of either gender,aged (6.8+0.8)months with a range of 5.5-8.0 months,were collected from Animal Laboratory Center of Army Medical University.were randomly divided into 15 in experimental group and 3 in control group.The swines in experimental group underwent IRE hepatic ablation with high-frequency bipolar pulse,and 3 swines were chose randomly and underwent enhanced CT examination immediately after ablation,and at 3,7,14,and 28 days after ablation.The liver tissues were taken for histopathological examination.The swines in the control group underwent IRE hepatic ablation with high-frequency monopolar burst,and was performed enhanced CT examination at 3 days after ablation.Liver tissues were taken for histopathological examination.Observation indicators:(1) comparison of muscle contraction of siwnes between two groups;(2) imaging performance on enhanced CT after IRE ablation in the experimental group;(3) hepatic histopathological findings after IRE ablation in the experimental group;(4) comparison of apoptotic index in the ablation zone between two groups.The measurement data with normal distribution were expressed as Mean±SD,and comparison between groups was performed by the independent sample t test.Results (1) Comparison of muscle contraction between two groups:swines in both groups underwent ablation successfully.The degree of muscle contraction was (9.8±0.4)m/s2 and (48.6±0.5) m/s2 in the experimental group and in the control group,respectively,showing statistically significant difference between the two groups (t =-163.50,P＜0.05).(2) Imaging performance on enhanced CT after IRE ablation in the experimental group:the enhanced CT examination of swines immediately after IRE ablation showed a low-density shadow and clear boundary in the ablation zone.There was no obvious abnormality in the ablation zone and its adjacent large vessels.No serious complications occurred after the ablation.The boundary between the ablation zone and the normal liver tissue of the experimental group gradually became blurred over time,and the ablation zone was gradually replaced by normal liver tissue.The ablation zone at the 28 days after ablation was significantly reduced or even disappeared on imaging of enhanced CT examination.The maximum diameter of the ablation zone was (1.81±0.17) cm immediately after ablation,(1.75±0.19) cm at the 3 days after ablation,(1.32±0.22)cm at the 7 days after ablation,(0.65±0.14)cm at the 14 days after ablation,(0.28±0.10)cm at the 28 days after ablation,respectively.(3) Hepatic histopathological findings after IRE ablation in the experimental group:the HE staining of ablated tissue immediately after ablation showed that the cells in the ablation zone were swollen,arranged disorderly,and bleeding was observed around some of the needles.The bile ducts and blood vessels were intact in the ablation zone,and a large number of deeply stained nuclei were seen at 3 days after ablation,some of the nucleus and apoptotic bodies were partially dissolved or cleaved.A large number of inflammatory cell were infiltrated around the ablation zone.Intact vascular and biliary endothelial cells were observed by yon Willebrand factor staining,a larger number of apoptotic cells with deeply stained nuclei in the ablation zone were observed by terminal-deoxynucleoitidyl transferase mediated nick end labeling staining,and partial deposited dark brown calcium salt was seen by Von Kossa staining.More newborn hepatocytes were observed growing from the periphery of the ablation zone to the center at the 7,14,28 days after ablation.Smooth muscle cell proliferation was observed at 14 and 28 days after ablation.The ablation zone was replaced by new cells on 28 days after ablation.(4) Comparison of apoptotic index in the ablation zone between two groups:the apoptotic index of the ablation zone was significantly higher in the experimental group than in the control group on the 3 days after operation (76.67％±0.04％ vs.64.03％±0.05％,t=4.79,P＜0.05).Conclusion IRE hepatic ablation of swine using high-frequency bipolar pulse is safe and reliable,and it has more apoptotic cells than IRE ablation with high-frequency monopolar burst.
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Objective@#To evaluate the clinical performance of HPV genotyping with cytology for detecting cervical precancer among women attending co-testing.@*Methods@#A total of 2 883 females who participated in cervical cancer screening program were recruited from Erdos in 2016. All the participants were tested by cytology and HPV genotyping. In 2017, women with abnormal cytology results or HPV positive were followed up. Pathological cervical intraepithelial neoplasia (CIN) 2+ was the study end-point. Clinical performance indexes were calculated, including sensitivity, specificity, positive predictive value, negative predictive value, referral rate and missed cases.@*Results@#INNO-LiPA resulted in a detection rate of 18.87%(544/2 883) for the 14-type high risk HPV. HPV16 was the most common infectious genotype (4.06%), followed by HPV52 (3.61%), HPV51 (2.50%), HPV58 (1.98%), and HPV18 (1.56%). With more HPV genotypes added into the group, sensitivity increased and the specificity decreased. Addition of HPV16, 58, 33, 39, 52, 18, 31 for detection lead to the maximun value of area under the curve (AUC)=0.913 (95%CI: 0.882-0.944). Compared with traditional screening method by cytology, cotesting decreased the number of missed diagnosis. Meanwhile, the fifth method (co-testing: triage of women with HPV16/18+ , cytological minor abnormalities and HPV58, 33, 39, 52, 31+ or cytological high grade abnormalities) did not increase referral rate (8.99% vs. 8.71%, P=0.525), with five cases of missed diagnosis (sensitivity of 92.1% and specificity of 93.2%).@*Conclusions@#Co-testing with triage of women with HPV16/18+ , cytological minor abnormalities and HPV58, 33, 39, 52, 31+ or cytological high grade abnormalities would provide better clinical performance. In co-testing, triage of HPV16/18 was used in women with normal cytology; triage of HPV58, 33, 39, 52 and 31 was used in women with low-grade abnormal cytology; referral colposcopy was used in women with high-grade abnormal cytology, which would provide better clinical performance.
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Objective@#To explore the relationship between high risk HPV (HR-HPV) DNA load and cervical lesions in HR-HPV single/ multiple infections.@*Methods@#Two thousand six hundred and forty-six women from Shanxi, Henan and Xinjiang were recruited into a cervical cancer screening program. Cervical exfoliated cell specimens collected from all of the participants were detected by hybrid capture Ⅱ (HC2), cytological diagnosis was performed according to the Bethesda System, and pathological diagnosis was interpreted using cervical intraepithelial neoplasia (CIN) terminology.Totally 571 cervical specimens were selected and retested to ascertain the HPV types and single/ multiple infections by liner array, a PCR-based method. Semi-quantitative result of HR-HPV DNA load (pg/ml) was estimated by HR HC2.According to the taxonomy of "International Human Papillomavirus Reference Center" , 13 HR-HPVs, including HPV16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and 68, which could be detected by HR HC2 were divided into 4 subgroups.@*Results@#The positive rate of HR-HPV in normal cervix (436 cases), CIN1 (88 cases), CIN2+ (47 cases) group were 29.82%, 85.23% and 100%, respectively. The overall prevalence and median viral load increased coordinating with the pathological degree of cervical lesions (P<0.001). The positive rate and viral load of single infection with HR-HPV belongs to α9 species increased coordinating with the pathological degree of cervical lesions (P<0.05). The viral load of single infection with HR-HPV belongs to α7 species in CIN1 group was higher than those of normal group and CIN2+ group, but without statistical significance (P=0.130). The viral load of multiple infections in CIN1 group was 559.13 pg/ml, significantly higher than 37.73 pg/ml of normal histology (P=0.025), but without significant difference of 332.91 pg/ml of CIN2+ group (P=0.790). The median viral load of HPV single infection in CIN1 group was 167.93 pg/ml, significantly lower than 559.73 pg/ml of multiple infections (P=0.044). The incidence of co-infection with HR-HPVs belong to α9 species was 80.56%, dominated in all patterns of multiple infections and their median viral load increased coordinating with the pathological degree of cervical lesions, but without significant difference (P>0.05). The incidence of co-infection with HR-HPVs belong to α7 species was 66.67%, their median viral load in CIN1 group was higher than that of CIN2+ group, but without statistical significance (P>0.05).@*Conclusions@#Viral loads of single/ multiple infections with HR-HPVs belong to different species show different tendencies coordinating with the pathological degree of cervical lesions. Women with high grade of cervical lesion were dominantly infected with high viral load of HR-HPVs belong to α9 species, and the viral load of multiple infections is higher than that of single infection in low grade of cervical lesion.
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Objective@#To evaluate the feasibility and effectiveness of isothermal human papillomavirus (HPV) DNA amplification test as a primary screening test in the early detection of cervical cancer.@*Methods@#From June to August 2016, 2, 774 women aged 30-64 years old from Inner Mongolia were recruited for cervical cancer screening. HPV DNA was detected by Isomega and cobas4800. INNO-LiPA HPV Genotyping Extra was served as a reference method for the cases whose results were inconsistent by using these two methods. Histological diagnosis was considered as a gold standard to estimate the effectiveness and accuracy of Isomega and cobas4800 for detecting CIN2 or greater.@*Results@#The concordance of Isomega and cobas4800 was 94.84% (Kappa=0.82) for high risk HPV (HR-HPV), 99.68% (Kappa=0.95) for HPV16, 99.78% (Kappa=0.91) for HPV18 and 94.34% (Kappa=0.76) for other HR-HPV types. The concordances of Isomega and the reference were 99.71% (Kappa=0.96), 99.86% (Kappa=0.94) and 96.76% (Kappa=0.87) for HPV16, 18 and other HR-HPV, respectively, while the concordances of cobas4800 and the reference were 99.82% (Kappa=0.97), 99.86% (Kappa=0.94) and 97.51% (Kappa=0.90), respectively. The sensitivity and specificity of Isomega for detecting CIN2+ (including CIN2, CIN3 and squamous cell carcinoma) were 87.76% and 82.94%, respectively, while those of cobas4800 were 89.80% and 85.06%, respectively.@*Conclusions@#The concordances of Isomega and cobas4800 is confident. These two methods can accurately detect the HPV16 and 18 genotyping, and have good sensitivity and specificity for clinical diagnosis and population screening of cervical cancer.
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Objective To compare the accuracy of 125I seeds longitudinal distance between groups by degradable catheters and hand.Methods The study was divided into two groups (implantation by degradable catheters and that by hand).There were 12 simulated lesions in each group.Seed needle and 125I seeds were implanted by three physicians according to the set longitudinal distance (0.5 and 1.0 cm).Postoperative CT was conducted and the longitudinal distance between seeds was measured,and then the data was analyzed between the actual distance and the designed distance in each group.Results The degree of deviation from the set distance were (0.184 ±0.047) and (0.127 ±0.051) cm in the group by hand,and (0.007 ± 0.006) and (-0.003 ± 0.006) cm in degradable catheters group.The degree of deviation of the seeds in the catheter group was significantly lower than the group by hand (t =3.804,2.499,P ＜0.05).Conclusions The accuracy of the longitudinal distance of the group by catheter is much better than that by hand.
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BACKGROUND@#The preferred therapy for patients with pulmonary nodules which highly suspected as lung cancer by low-dose spiral computed tomography (CT) is surgery, but the best screening method of whole body is not clear yet. The aim of this study is to investigate the differences in the progression-free survival (PFS) of patients with Ia stage non-small cell lung cancer after screening of positron emission computed tomography (PET)-CT and conventional imaging (B-ultrasound/CT/MRI/ECT, BCME).@*METHODS@#A total of 300 cases of Ia stage non-small cell lung cancer were collected, of which 170 cases were performed PET-CT and 130 cases were performed BCME before operation. The basic characteristics of the two groups were analyzed by propensity score matching (PSM), and 114 cases of each group were included in the study. The survival analysis was carried out by the Kaplan-Meier survival curve and the Cox regression analysis.@*RESULTS@#There was no significant difference between each group analyzed by PSM. The PFS of PET-CT and BCME were (44.9±27.2) months and (44.1±33.1) months (χ2=1.284, P=0.257). Both of the method ssucceed in screening. It is not the PFS influence factors. The false positive of PET-CT and BCME were 10 cases and 8 cases (χ2=0.241, P=0.623).@*CONCLUSIONS@#Both PET-CT and BCME can be used as a screening method for Ia stage non-small cell lung cancer according to individualized choice of patients.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Carcinoma, Non-Small-Cell Lung , Diagnostic Imaging , Pathology , General Surgery , Disease-Free Survival , Early Detection of Cancer , Methods , Fluorodeoxyglucose F18 , Lung Neoplasms , Diagnostic Imaging , Pathology , General Surgery , Neoplasm Staging , Positron Emission Tomography Computed Tomography , Preoperative PeriodABSTRACT
Objective To investigate the risk factors of pneumorrhagia and pneumothorax occurring after CT-guided cutting needle biopsy for pulmonary solid nodules.Methods The clinical data and imaging materials of 320 patients with pulmonary solid nodule (≤3 cm),who received 16 G semi-automatic cutting needle biopsy,were retrospectively analyzed.Both univariate and multivariate logistic regression analysis methods were used to evaluate the risk factors of pneumorrhagia and pneumothorax.Results The incidence of needle track hemorrhage was 33.1％ and the incidence of pneumothorax was 18.1％,the diagnostic accuracy for benign and malignant nodules was 99.6％.Needle track length was an independent risk factor for pneumorrhagia;every increase of 3 cm in needle track length,the risk of pneumorrhagia would increase 3.881 times,besides,the risk of pneumorrhagia had a parallel relationship with the time used for puncturing (P=0.061) as well as with the number of pleural puncturing (P=0.062).The age,lesion's location and needle-pleural angle were independent risk factors for pneumothorax.Each increase of 10 years in age,the risk of pneumothorax would increase 2.102 times.The pneumothorax risk of pulmonary lesion located at upper lung lobe was strikingly lower than that of pulmonary lesion located at lower lung lobe.Each increase of 20 degrees in needle-pleural angle,the risk of pneumothorax would increase 2.413 times.Emphysema was excluded from the equation because it had only a minute difference (P=0.086).Based on the pneumorrhagia and pneumothorax probability values,ROC curves of pneumorrhagia and pneumothorax were drawn,and AUC values of pneumorrhagia and pneumothorax were 0.753 and 0.725 respectively.Conclusion The occurrences of pneumorrhagia and pneumothorax after CT-guided cutting needle biopsy for pulmonary solid nodules are affected by many factors.Careful preoperative evaluation and skilled intraoperative manipulation can effectively reduce the incidence of pneumorrhagia and pneumothorax.
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Objective To evaluate the accuracy of magnifying endoscopy with narrow-band imaging (ME-NBI) for detecting early esophageal cancer invasion depth. Methods We searched Embase, Pubmed, Web of Science, Cochrane Library, CBM, CNKI, Wanfang and VIP databases from inception to Feb.2016. Domestic articles related to the accuracy of ME-NBI detecting the early esophageal cancer invasion depth were collected comprehensively. The quality of the papers was evaluated by quality assessment of diagnostic accuracy studies (QUADAS). Data analysis was conducted by Stata 12.0 software. Results Seven group data from six studies including 319 patients with 366 lesions met the inclusion criteria. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, SROC area under the curve and DOR were 93.8 % (95 % CI: 0.886~0.967), 75.2 % (95 % CI: 0.658~0.827), 3.779 (95 % CI: 2.685 ~ 5.318), 0.083 (95 % CI: 0.044~0.155), 0.80 (95 % CI: 0.770~0.840) and 45.658 (95 % CI:21.006~99.240). Conclusions The results suggest that ME-NBI may be an effective tool for detecting invasion depth of early esophageal cancer, which plays an important role in clinical selection of surgical approach and treatment.
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The number average molecular weights of five fractionated samples of pomelo pectin were determined osmometrically in aqueous solution. The values of Mn ranged from 4.74?104 to 1.83?144 for different fractions.From the data of osmotic pressure and intrinsic viscosity, the [?]-M relation obtained is[?]3.23?10-7M1.75in 0.9% NaCl solution of pH 4.83 at 37℃.