OBJECTIVE: To explore the design points of a three-dimensional (3D) printed customized cementless intercalary endoprosthesis with an intra-neck curved stem and to evaluate the key points and mid-term effectiveness of its application in the reconstruction of ultrashort bone segments in the proximal femur. METHODS: Between October 2015 and January 2021, 17 patients underwent reconstruction with a 3D printed-customized cementless intercalary endoprosthesis with an intra-neck curved stem. There were 11 males and 6 females, the age ranged from 10 to 76 years, with an average of 30.1 years. There were 9 cases of osteosarcoma, 4 cases of Ewing sarcoma, 2 cases of chondrosarcoma, 1 case of liposarcoma, and 1 case of myofibroblastoma. The disease duration was 5-14 months, with an average of 9.5 months. Enneking staging included 16 cases of stage ⅡB and 1 case of stage ⅢB. The distances from the center of the femoral head to the body midline and the acetabular apex were measured preoperatively on X-ray images. Additionally, the distances from the tip of the intra-neck curved stem to the body midline and the acetabular apex were measured at immediate postoperatively and last follow-up. The neck-shaft angle was also measured preoperatively, at immediate postoperatively, and at last follow-up. The status of osseointegration at the bone-prosthesis interface and bone growth into the prosthesis surface were assessed by X-ray films, CT, and Tomosynthesis-Shimadzu metal artefact reduction technology (T-SMART). The survival status of the patients, presence of local recurrence or distant metastasis, and occurrence of postoperative complications were assessed. The recovery of lower limb function was evaluated pre- and post-operatively using the Musculoskeletal Tumor Society (MSTS) scoring system, and pain relief was evaluated using the visual analogue scale (VAS) scores. RESULTS: The patient's femoral resection length was (163.1±57.5) mm, the remaining proximal femoral length was (69.6±9.3) mm, and the percentage of femoral resection length/total femoral length was 38.7%±14.6%. All 17 patients were followed up 25-86 months with an average of 58.1 months. During the follow-up, 1 patient died of lung metastasis at 46 months postoperatively, and the remaining 16 patients survived tumor-free. There was no complication such as periprosthetic infection, delayed incision healing, aseptic loosening, prosthesis fracture, or periprosthetic fracture. No evidence of micromotion or wear around the implanted stem of the prosthesis was detected in X-ray and T-SMART evaluations. There was no significant radiolucent lines, and radiographic evidence of bone ingrowth into the bone-prosthesis interface was observed in all stems. There was no significant difference in the distance from the tip of the curved stem to the body midline and the apex of the acetabulum at immediate postoperatively and last follow-up compared with the distance from the center of the femoral head to the body midline and the apex of the acetabulum before operation, respectively (P>0.05), and there was no significant difference in the above indexes between immediate postoperatively and last follow-up (P>0.05). The differences in the neck-shaft angle at various time points before and after operation were also not significant (P>0.05). At last follow-up, the MSTS score was 26.1±1.2 and the VAS score was 0.1±0.5, which were significantly improved when compared with those before operation [19.4±2.1 and 5.7±1.0, respectively] (t=14.735, P<0.001; t=21.301, P<0.001). At last follow-up, none of the patients walked with the aid of crutches or other walkers. CONCLUSION The 3D printed customized cementless intercalary endoprosthesis with an intra-neck curved stem is an effective method for reconstructing ultrashort bone segments in the proximal femur following malignant tumor resection. The operation is reliable, the postoperative lower limb function is satisfactory, and the incidence of complications is low.
Female ; Male ; Humans ; Child ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Aged ; Femur/surgery* ; Lower Extremity ; Bone-Implant Interface ; Femur Head ; Artificial Limbs

Objective:To evaluate the safety and efficacy of a dedicated neonatal-infant brain 0.35 T MRI system.Methods:A dual-center controlled clinical trial was conducted with single-arm objective performance criteria. From June to July 2020, sixty-six infants aged 0-12 (6.3±3.4) months were recruited from Children′s Hospital of Soochow University and the First People′s Hospital of Lianyungang prospectively. All infants underwent brain MRI with a dedicated neonatal-infant 0.35 T brain MRI system, using the dedicated two-channel transceiver head coil. MRI protocol included spin echo T 1WI, fast spin echo T 2WI, fluid attenuated inversion recovery, diffusion weighted imaging and 3D gradient echo sequence. MRI sequences were set with three orientations (axial, sagittal and coronal). Each case received at least two scanning planes and two scanning sequences. Five-point Likert scoring system was used to evaluate the image quality of acquired images, and the target value was set as at least 3 points per image. The temperature, heart rate and breathe of the infants were recorded before and after MRI; the acoustic noise of the MRI system was measured during the scanning process; and the adverse reactions were recorded if presented. Results:Five infants successfully completed their examination during non-sedated sleep in a single attempt, and 61 infants after sedation with chloral hydrate. Based on MRI-based five-point Likert scoring system, 41 cases achieved a score of 5, 21 cases with a score of 4 and 4 cases with a score of 3. Cases with score of 3 was due to movement of the infants during the scan, which resulted in motion related artifacts. The vital signs of all infants showed stable before and after imaging, with heart rate of (126.8±12.9) beats per minute, breathe of (38.2±6.8) times per minute. It was found that 47 cases showed no sign of temperature raise after brain MRI, 15 cases had less than 0.3 ℃ raise and 4 cases had 0.3 ℃ to 0.5 ℃ raise. The noise recorded during the scanning process was (57.5±1.8) dB(A). One case had mild diarrhea on the day of MR scan, and the symptoms disappeared on the second day without treatment; no adverse reactions were found for the rest subjects.Conclusion:Dedicated neonatal-infant 0.35 T brain MRI system allows data acquisition with high safety and excellent image quality, which has potentials in the clinical applications.

Objective: To evaluate the accuracy and feasibility of coronary artery calcium score ( CACS) on virtual non-contrast scan ( VNC) images obtained from coronary artery CT angiography ( CCTA) scan with dual －layer spectral detector CT (SDCT) ． Methods : The data of 197 patients who underwent CCTA scan in hospital were analyzed retrospectively，and 88 patients with CACS ＞0 were further analyzed． Linear regression analysis of CACS and coronary artery calcium volume ( CACV) of true non-contrast (TNC) images and VNC images ( CACS-TNC， CACS-VNC，CACV-TNC，CACV-VNC) was performed to obtain linear regression equation and correction coefficients λ 1AVG and λ2AVG ．CACS-VNC and CACV-VNC were corrected by the corresponding regression equation and recorded as CCACS-VNC and CCACV-VNC，respectively．Spearman correlation coefficient was used for correlation analysis and Bland-Altman plot was used for consistency test．Mann-Whitney U test was used to compare the difference between the two groups. Results : For the total coronary artery，there was a strong correlation between CACS- TNC and CACS-VNC (rs = 0. 952，P ＜0. 001 ，λ 1AVG = 2. 19 ) ，CACV-TNC and CACV-VNC ( rs = 0. 954，P < 0. 001，λ2AVG = 1. 93) ．The results of Mann-Whitney U test showed that there was no significant difference between CACS-TNC and CCACS-VNC or between CACV-TNC and CCACV-VNC，and the Bland-Altman plot showed good consistency between CACS-TNC and CCACS-VNC ，CACV-TNC and CCACV-VNC． Conclusion VNC images based on SDCT can accurately measure CACS and be used for cardiovascular risk classification，which is expected to replace TNC scan and reduce the radiation dose of patients.

Objective:To study the effectiveness of a strategy for detecting early gastric cancer using high-definition gastroscopy.Methods:A total of 849 patients over 35 years old who underwent gastroscopy in the Seventh Medical Center of PLA General Hospital from December 2018 to January 2019 were enrolled to a prospective study. During gastroscopy, biopsies were taken at any suspicious lesions in patients who had never been infected with Helicobacter pylori. In ulcer-type lesions, biopsies were taken at the edge of the ulcer. Outside the atrophic area, biopsies were taken at lesions in the cardia which were reddish under white light, or lesions in the non-cardiac area which were white or showed clear borders under white light. Inside the atrophic area, biopsies were taken at elevated lesions with clear borders or irregular depressions on the top, or flat/depressed lesions with irregular borders or being ocherous under narrow band imaging. In addition, biopsies were performed on any lesion that did not meet the above standard but was considered necessary. The high-risk patients were followed up by gastroscopy to observe the detection and missed diagnosis of neoplasm that meet the above standard, and to determine the sensitivity and positive predictive value of the strategy. Results:A total of 548 patients were biopsied (781 lesions). Among the 327 lesions that met the above standard, 16 lesions (4.9%) were diagnosed as epithelial neoplasm, of which 10 (3.1%) were high-grade neoplasm. Among the 454 lesions that did not meet the standard, only 1 (0.2%) epithelial neoplasm was diagnosed, and there was no high-grade neoplasm. The positive predictive value of this screening strategy for gastric epithelial neoplasm and high-grade neoplasm was higher than those who did not meet the standard (4.9% VS 0.2%, χ2=19.49, P<0.01; 3.1% VS 0, P<0.001). There were 146 patients (17.2%, 146/849) followed up by gastroscopy. During the follow-up, 2 high-grade intramucosal neoplasms were found. 84.2% (16/19) of epithelial tumors and 83.3% (10/12) of high-grade neoplasm were detected during the initial gastroscopy. Conclusion:This screening strategy can efficiently detect early gastric cancer under high-definition gastroscopy.

To investigate the efficacy and safety of endoscopic bougie dilation and stent implantation for pediatric caustic esophageal stenosis. Clinical characteristics, diagnosis and treatment of children with pediatric caustic esophageal stenosis from October 2009 to December 2019 at Department of Gastroenterology, the Seventh Medical Center of PLA General Hospital were retrospectively analyzed. A total of 50 caustic esophageal stenosis cases were enrolled, among whom, 94.0% (47/50) received conservative treatment before sending to our hospital. Thirty-six (72.0%) of them accidently ingested caustic substance of alkali and 22.0% (11/50) of them accidently ingested caustic substance of acid. Forty-six children (92.0%) who ingested caustic agents were younger than 7 years old. The stenosis was more common in the upper esophagus, accounting for 64.0% (32/50). Twenty-seven cases (54.0%) underwent simple bougie dilation and 16 cases (32.0%) underwent bougie dilation combined with stent treatment. All 50 children underwent a total of 1 260 expansions. The numbers of simple dilations and dilations combined with stent implantation were 37.8±26.2, 20.9±12.6 respectively with significant difference ( t=2.453, P=0.021). Among them, 2 cases (4.0%) underwent surgery, 5 cases (10.0%) underwent surgery combined with dilatation and stent implantation. The stenosis diameter widened significantly after treatment (1.1±0.2 cm VS 0.2±0.1 cm, t=23.004, P<0.001), and the Stooler grade of dysphagia improved significantly (grade 3.5±0.5 VS 1.2±0.7, t=19.925, P<0.001). Perforation occurred in only 1 patient, who was cured by conservative treatment with stent implantation. The total effective rate was 100.0% (50/50) and the satisfaction rate was 98.0% (49/50). Endoscopic bougie dilation and bougie dilation combined with stent implantation is safe and effective for pediatric caustic esophageal stenosis. Combination with stent implantation can reduce the number of dilation times.

Overexpression of ABCG2 transporter in cancer cells has been linked to the development of multidrug resistance (MDR), an obstacle to cancer therapy. Our recent study uncovered that the MET inhibitor, tepotinib, is a potent reversal agent for ABCB1-mediated MDR. In the present study, we reported for the first time that the MET inhibitor tepotinib can also reverse ABCG2-mediated MDR in vitro and in vivo by directly binding to the drug-binding site of ABCG2 and reversibly inhibiting ABCG2 drug efflux activity, therefore enhancing the cytotoxicity of substrate drugs in drug-resistant cancer cells. Furthermore, the ABCB1/ABCG2 double-transfected cell model and ABCG2 gene knockout cell model demonstrated that tepotinib specifically inhibits the two MDR transporters. In mice bearing drug-resistant tumors, tepotinib increased the intratumoral accumulation of ABCG2 substrate drug topotecan and enhanced its antitumor effect. Therefore, our study provides a new potential of repositioning tepotinib as an ABCG2 inhibitor and combining tepotinib with substrate drugs to antagonize ABCG2-mediated MDR.

Objective:To analyze the endoscopic and histological characteristics of Helicobacter pylori ( HP)-negative early gastric cancer (EGC) and high grade intraepithelial neoplasia (HGIN). Methods:Data of patients diagnosed as having EGC or HGIN confirmed by pathology at the Seventh Medical Center of Chinese People′s Liberation Army General Hospital from January 2013 to January 2020 were collected. Patients were included according to the diagnostic criteria of HP-negative gastric cancer, and their endoscopic features and histopathological characteristics were retrospectively analyzed. Results:Among 469 lesions of EGC/HGIN, HP-negative lesions accounted for 2.1% (10/469), which included 3 signet ring cell carcinomas, 3 fundic gland type carcinomas, 1 foveolar adenocarcinoma, 1 HGIN of the cardia, 1 familial adenomatous polyposis with gastric HGIN, and 1 Lynch syndrome with gastric HGIN. The 3 cases of signet ring cell carcinoma were all whitish flat/depressed lesions and commonly seen in the lower part of the stomach (2/3). Most of the 7 cases of differentiated EGC/HGIN were elevated type (5/7) and commonly seen in the upper and middle stomach (6/7). Conclusion:HP-negative EGCs are usually solitary lesions under gastroscopy. Undifferentiated type mostly appears whitish flat/depressed in the lower part of the stomach, while differentiated type appears elevated in the upper and middle part.

Objective:To propose a strategy for detecting early gastric cancer (EGC) under high-definition gastroscopy.Methods:Data of 469 lesions of EGC or high grade intraepithelial neoplasia (HGIN) confirmed by pathology detected at The Seventh Medical Center of Chinese People′s Liberation Army General Hospital from January 2013 to January 2020 were collected and gastroscopic images were re-interpreted. The Helicobacter pylori ( HP) infection status, lesion location in the area of atrophy or at the cardia, morphological type of lesions, lesions with/without clear or regular boundary, and lesion color were analyzed for morphological characteristics of EGC and HGIN under high-definition gastroscopy. Results:Among the 469 lesions of EGC or HGIN, HP-negative lesions accounted for 2.1% (10/469) and ulcerative lesions for 7.7% (36/469). Among non-ulcerative lesions of suspected HP infection ( n=423), there were 28 lesions in the cardia outside the atrophic area and 82.1% (23/28) were reddish under white light imaging. There were 29 non-cardiac lesions outside the atrophic area and 82.8% (24/29) were white or showed clear border under white light imaging. Inside the atrophic area, there were 73 elevated lesions, 95.9% (70/73) of which had clear border or irregular depression on the top. There were 293 flat/depressed lesions in the atrophic area, and 90.8% (266/293) had irregular border or were brown under narrow band imaging. Conclusion:According to the status of HP infection, the location and morphological category of lesions, above endoscopic features can be used as clues to detect EGC and HGIN.

Objective:To evaluate the relationship between transforming growth factor beta-3 (TGF-β 3)/mammalian homologs of the drosophila mad gene 3 (Smad3) signaling pathway and neuronal apoptosis during reduction of focal cerebral ischemia-reperfusion (I/R) injury by isoflurane postconditioning (ISO) in rats. Methods:Sixty clean-grade healthy male Sprague-Dawley rats, aged 6-8 weeks, weighing 210-230 g, were randomly divided into 5 groups ( n=12 each): sham operation group (group S), cerebral I/R group (group I/R), cerebral I/R plus isoflurane postconditioning group (group I/R+ ISO), cerebral I/R plus pirfenidone group (group I/R+ P), and cerebral I/R plus isoflurane postconditioning plus pirfenidone group (group I/R+ ISO+ P). Local cerebral I/R was produced by middle cerebral artery occlusion for 1.5 h followed by 24-h reperfusion in anesthetized rats.Pirfenidone 5 μg/kg was injected into the lateral ventricle at 30 min before ischemia in I/R+ P and I/R+ ISO+ P groups.In I/R+ ISO and I/R+ ISO+ P groups, 1.5% isoflurane was inhaled for 1 h starting from the time point immediately after onset of reperfusion.Neuro-functional deficit was assessed using neurologic deficit scores (NDS) at the end of reperfusion.Then the animals were sacrificed, and brain tissues were removed for determination of the neuronal damage rate (by Nissl staining), neuronal apoptosis rate (by TUNEL), expression of TGF-β 3 (using immunofluorescence), and expression of TGF-β 3, phosphorylated Smad3 (p-Smad3), caspase-3, Bax and Bcl-2 (by Western blot). Results:Compared with group S, the NDS, neuronal damage rate and apoptosis rate of neurons were significantly increased, the expression of TGF-β 3, caspase-3 and Bax was up-regulated, and the expression of p-Smad3 and Bcl-2 was down-regulated in group I/R ( P<0.05). Compared with group I/R, the NDS, neuronal damage rate and apoptosis rate of neurons were significantly decreased, the expression of TGF-β 3, p-Smad3 and Bcl-2 was up-regulated, and the expression of caspase-3 and Bax was down-regulated in group I/R+ ISO, and the NDS, neuronal damage rate and apoptosis rate of neurons were significantly increased, the expression of TGF-β 3 and p-Smad3 was down-regulated, and the expression of caspase-3 was up-regulated in group I/R+ P ( P<0.05). Compared with group I/R+ ISO, the NDS, neuronal damage rate and apoptosis rate of neurons were significantly increased, the expression of TGF-β 3, p-Smad3 and Bcl-2 was down-regulated, and the expression of caspase-3 and Bax was up-regulated in group I/R+ ISO+ P ( P<0.05). Conclusion:Isoflurane postconditioning can inhibit neuronal apoptosis by activating the TGF-β 3/Smad3 signaling pathway, thus reducing focal I/R injury in rats.

Objective To evaluate the clinical value of epithelial vessel branch detected by non-magnifying narrow-band imaging ( NM-NBI ) in diagnosis of early esophageal cancer. Methods A retrospective analysis was performed on data of 59 patients, who underwent endoscopy with NM-NBI and iodine staining to screen early esophageal cancer in PLA General Hospital from January 2013 to May 2015. The final diagnosis for all lesions were determined by pathology. The diagnostic accuracy, sensitivity and specificity of NM-NBI and iodine staining for early esophageal cancer were compared. Results The accuracy, sensitivity and specificity of NM-NBI on the epithelial vessel branch in diagnosis of early esophageal cancer were 83. 1％ (49/59), 91. 3％ (21/23) and 77. 8％ (28/36), respectively, and the corresponding statistical values of iodine staining were 55. 9％ ( 33/59) , 95. 7％ ( 22/23) and 30. 6％ ( 11/36), respectively. The accuracy (χ2=1. 45, P=0. 028) and specificity (χ2=21. 4, P=0. 000) of epithelial vessel branch by NM-NBI were significantly higher than those of iodine staining, and there was no significant difference in the sensitivity between the two methods (χ2=22. 3, P=1. 000) . Conclusion The observation of epithelial vessel branch using NM-NBI was useful and reliable in diagnosis of early esophageal cancer with high accuracy and specificity, and can be possible for application in the clinic.