Objective To summarize and analyze the different modality on molecular imaging of tracking and monitoring for islet transplantation．Methods The current domestic and foreign reports on molecular imaging of islet transplantation were reviewed．Results Magnetic resonance imaging has high sensitivity，high spatial resolution，no ionizing radiation，is clinically applicable，and could be used of real-time MR-guided injections，but can’t discriminate between liver and dead cells，difficult to do in patients with liver iron overload．Nuclear molecular imaging only displays liver cells generate signal，is clinically applicable，but disadvantage is genetic manipulation，ionizing radiation，no anatomical information，low spatial resolution．The advantage of in vivo optical imaging is only liver cells generate signal，widely available，no ionizing radiation，and the disadvantage is genetic manipulation，not clinically applicable，low spatial resolution．Conclusions Islet imaging using magnetic resonance，nuclear molecular imaging，in vivo optical imaging，or multimodal imaging of microencapsulated islets may provide us with a direct means to interrogate islet cell distribution，survival，and function．Multimodal imaging of microencapsulated islets may be best way for tracking and monitoring in the future．
Accurate placement of pedicle screws is a key factor of spinal surgery. Investigation of a new real-time intra-operative monitoring method is an important area of clinical application research which makes a contribution to planting pedicle screw accurately. Porcine spines were chosen as experimental objects.The changes of reduced scattering coefficient (μ's) along normal puncture path, medial perforation path and lateral perforation path were measured and studied. A conclusion is drawn that there are two distinct peaks throughout the puncture process, appearing at the junction of cancellous bone and cortical bone, at the beginning and at the end, respectively. The reduced scattering coefficient is proved to be a good monitoring factor which can identify whether the screw is about to reach the critical position of the spine puncture. Moreover, the variation provides an important reference for spinal surgical navigation process.
ObjectiveTo explore the status of the career maturity of medical students (eight-year program) and its related factors. MethodsFrom April to June in 2010, College Students Maturity Self-test Questionnaire was used for the investigation of the career maturity of the medical students (eight-year program) at West China Medical School of Sichuan University. ResultsThe subjects were graded into three groups according to the scores of their questionnaires:high, moderate, and low career maturity. The proportion of each group was 15.2%, 13.8%, 71.0%, respectively. Gender difference was not found in the overall career maturity (Z=-0.206, P=0.837), while there was positive correlation between grade and overall career maturity (rs=0.180, P=0.030). ConclusionThe medical students (eight-year program) with relatively low overall career maturity account for a larger proportion than those with high and median career maturity. As grade increases, career maturity changes significantly. This research suggests that long schooling medical students are in urgent need for prompt and valid professional career education.
ObjectiveTo evaluate the diagnostic value of magnetic resonance cholangiopancreatography (MRCP) for biliary strictures post-orthotopic liver transplantation (OLT). MethodsA systematic review was performed by searching electronic bibliographic databases, including the Cochrane Library, Medline, EMbase, CNKI, and WanFang from 1994 to 2014. The pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were used to describe the diagnostic value. Summary receiver operating characteristic (SROC) curve with area under the SROC curve (AUC) were used to summarize overall diagnostic performance. ResultsSix studies involving 261 subjects were eligible for the analysis. The summary estimates of pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and AUC of MRCP for the diagnosis of biliary strictures after OLT were 89% (95% CI:0.83-0.94), 94% (95% CI:0.88-0.98), 8.04 (95% CI:2.83-22.85), 0.11 (95% CI:0.04-0.37), and 0.961, respectively. ConclusionMRCP is a sensitive and specific technique to diagnose biliary strictures after OLT.
Medical magnetic nanoparticles are nano-medical materials with superparamagnetism, which can be collected in the tumor tissue through blood circulation, and magnetic particle imaging technology can be used to visualize the concentration of magnetic nanoparticles in the living body to achieve the purpose of tumor imaging. Based on the nonlinear magnetization characteristics of magnetic particles and the frequency characteristics of their magnetization, a differential detection method for the third harmonic of magnetic particle detection signals is proposed. It was modeled and analyzed, to study the nonlinear magnetization response characteristics of magnetic particles under alternating field, and the spectral characteristics of magnetic particle signals. At the same time, the relationship between each harmonic and the amount of medical magnetic nanoparticle samples was studied. On this basis, a signal detection experimental system was built to analyze the spectral characteristics and power spectral density of the detected signal, and to study the relationship between the signal and the excitation frequency. The signal detection experiment was carried out by the above method. The experimental results showed that under the alternating excitation field, the medical magnetic nanoparticles would generate a spike signal higher than the background sensing signal, and the magnetic particle signal existed in the odd harmonics of the detected signal spectrum. And the spectral energy was concentrated at the third harmonic, that is, the third harmonic magnetic particle signal detection that meets the medical detection requirement could be realized. In addition, the relationship between each harmonic and the particle sample volume had a positive growth relationship, and the detected medical magnetic nanoparticle sample volume could be determined according to the relationship. At the same time, the selection of the excitation frequency was limited by the sensitivity of the system, and the detection peak of the third harmonic of the detection signal was reached at the excitation frequency of 1 kHz. It provides theoretical and technical support for the detection of medical magnetic nanoparticle imaging signals in magnetic particle imaging research.
Objective To explore the molecular mechanism of LINC00626 regulating malignant progression of lung adenocarcinoma metastasis through JAK1/STAT3/KHSRP axis. Methods Quantitative real-time polymerase chain polymerase chain reaction was used to detect the expression of LINC00626 and KHSRP mRNA in human non-small-cell lung carcinoma cell lines (A549, H1299, H1975, H1437), human normal bronchial epithelial cell line (16HBE) and 144 lung adenocarcinoma tissues. The knockdown LINC00626 lentivirus and the control lentivirus were transferred into H1299 and H1437 cells, and named as sh-LINC00626 group (silencing of LINC00626 by transfecting short hairpin RNA lentiviral vector and sh-NC Group negative control by transfecting short hairpin RNA lentiviral). The overexpressed LINC00626 lentivirus and the control lentivirus were transferred into A549 and H1975 cells and named as LINC00626 group and Vector group. KHSRP vector on the basis of silencing LINC00626 and blank vector on the basis of silencing LINC00626 were added in H1437 cells. Cell counting kit-8 assay and Transwell migration/invasion assay were used to detect cell proliferation, migration and invasion. The expression levels of JAK/STAT and KHSRP in stably transfected cells were detected by Western blot. The effect of LINC00626 in vivo was studied in nude mice. Nuclear-cytoplasmic separation and RNA fluorescence in situ hybridization assay are used to predict the subcellular localization of LINC00626 and KHSRP. RNA pull down and mass spectrometry analysis were used to identify LINC00626 binding proteins. Results The expression levels of LINC00626 and KHSRP in non-small-cell lung carcinoma cell lines were significantly higher than those in normal human bronchial epithelial cells. LINC00626 and KHSRP were highly expressed in lung adenocarcinoma. Compared with the control group, the cell proliferation rate, colony formation, cell migration and invasion of H1437 cells were significantly decreased in knockdown group, while the reverse was true for over-expression. LINC00626 and KHSRP were located in the nucleus. LINC00626 directly binded to the KHSRP protein. Compared with the control group, H1437 cells transfected with knockdown LINC00626 and KHSRP significantly increased cell proliferation rate, cell migration, number of invasions. Compared with the control group, knockdown group showed a significant decrease in tumor volume and weight, cell proliferation rate and proliferation index, and the number of lung metastases. While the overexpression group showed an opposite effect, there were significant differences among the groups (P<0.01). The expression of JAK1 and STAT3 mRNA and protein in sh-LINC00626 group was lower than that in sh-NC Group (P<0.05), and the expression of JAK1 and STAT3 mRNA and protein in sh-LINC00626 group was higher than that in Vector group (P<0.05). Conclusion LINC00626 promotes malignant progression of lung adenocarcinoma metastasis through JAK1/STAT3/KHSRP signaling axis.
ObjectiveTo explore the relationship between the signal intensity on hepatobiliary phase of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI and the degree of differentiation of hepatocelluar carcinoma (HCC). MethodsForty-eight cases of HCC with Gd-EOB-DTPA-enhanced MRI images in our hospital were retrospectively included. The signal to noise ratio (SNR), contrast ratio (CR), enhancement ratio of signal to noise ratio (%EnhancementSNR), enhancement ratio of the contrast ratio (%EnhancementCR), enhancement ratio (ER), and relative enhancement ratio (RER) were calculated, respectively. Then comparisons of these signal values among different differentiations of HCC were performed. ResultsAmong the 48 cases of HCC, there were 6 cases of well differentiated, 24 cases of moderately differentiated, and 18 cases of poorly differentiated. There were 37 cases of Child-Turcotte-Pugh (CTP)A classification and 11 cases of B classification, respectively. Neither in all cases nor in cases of CTP A classification, there was no statistically significant difference in SNR, CR, %EnhancementSNR, %EnhancementCR, ER, and RER among cases of different differentiation (P > 0.05). ConclusionThe signal intensity on hepatobiliary phase images of Gd-EOB-DTPA-enhanced MRI has limited value in predicting the degree of differentiation of HCC.
ObjectiveTo investigate the application value of contrast-enhanced ultrasound (CEUS) technique to assist the repair of oral and maxillofacial defects by superficial inferior epigastric artery perforator flap.MethodsSixteen oral cancer patients, 10 males and 6 females, who were to undergo superficial inferior epigastric artery perforator flap repair between June 2018 and February 2020, were selected, with an average age of 55.8 years (range, 24-77 years). There were 13 cases of squamous cell carcinoma, 2 cases of adenoid cystic carcinoma, and 1 case of mucinous epidermis-like carcinoma. The color Doppler ultrasound (CDUS) and CEUS were used to screen the superficial inferior epigastric artery, assisted in the design of the flap, and compared it with the actual intraoperative exploration. The sensitivity, specificity, positive predictive value, and negative predictive value of CEUS and CDUS examinations were analyzed. Fourteen of 16 patients were repaired with superficial inferior epigastric artery perforator flap, and 2 patients were repaired with superficial iliac artery flap because the source artery was not found. After surgery, regular follow-up was performed to check for disease recurrence and metastasis and to evaluate the appearance of the patien’s donor area, the recovery of transoral feeding function, and the presence of complications.ResultsComparison of preoperative CDUS and CEUS findings and intraoperative exploration showed that CEUS had 100% sensitivity, specificity, positive predictive value, and negative predictive value for vascular exploration of the superficial inferior epigastric artery perforator flap, compared with 57%, 100%, 100%, and 25% for CDUS. The preoperative CDUS identified 25 penetrating vessels in 14 cases repaired with superficial inferior epigastric artery flaps. All vessel signals were enhanced by CEUS enhancement, and an additional 11 penetrating vessels were identified confirmed intraoperatively. The preoperative CEUS measurements of the initial diameter of superficial arteries in the abdominal wall were significantly higher than both CDUS and intraoperative measurements (P<0.05); the difference in peak systolic velocity between CEUS and CDUS measurements was significant (t=3.708, P=0.003). One case of superficial epigastric artery perforator flap developed venous embolism crisis at 48 hours after operation, the wound healing delayed. The other incisions in donor sites healed by first intention. All the patients were followed up 3-12 months, with an average of 8 months. No recurrence or metastasis appeared during the follow-up. There was no serious complications such as abdominal wall hernia, the location of abdominal scarring was hidden, and transoral feeding was resumed.ConclusionThe superficial inferior epigastric artery perforator flap with small injury in supply area and hidden scar location is a better choice for repairing oral and maxillofacial defects. The use of CEUS technique to assist the preoperative design of the superficial inferior epigastric artery perforator flap has good feasibility and high accuracy.