In case of ischemic stroke(IS),thrombus in the vascular system can cause ischemia and hypoxia in brain tissue,produce inflammatory cytokines and cause brain tissue damage,while reactive oxygen species during ischemia-reperfusion cause stress injury.Conventional drug administra-tion is limited by the selective permeability of the blood-brain barrier and the low bioavailability of the drug itself,and its therapeutic effect against IS is unsatisfactory.Nanomedicine is expected to bring hope in that it has a unique mechanism of action and can cross the blood-brain barrier to reach the periphery of the infarct,release drugs or therapeutic genes,and exert a therapeutic effect.Nanomedi-cine inhibits platelet aggregation,enhances the efficacy of thrombolytic drugs,dissolves thrombus,increases blood supply to ischemic areas,eliminates reactive oxygen species and weakens injury response by fighting inflammatory cytokines.Loaded therapeutic genes regulate the differentiation pro-cess of neural stem cells,increase the number of neurons,induce the occurrence of blood vessels,and enhance the repair function of brain tissue.Nanomedicines can not only improve pharmacokinetics and pharmacodynamics to achieve more effective drug treatment,but also use nanoimaging technology to achieve real-time monitoring and condition assessment of therapy.

Objective:To introduce the stereotactic cardiac radioablation (SCRA) based on the stereotactic body radiotherapy (SBRT), and comprehensively evaluate the new approach by short-term effectiveness and safety.Methods:Patients with ventricular arrhythmia (VA) were evaluated and included in this clinical trial, who were immobilized by vacuum bag and performed simulation with 4-dimensional computed tomography (4DCT). In this study, the planning target volume (PTV) was set as the target to design a SBRT plan using volumetric modulated arc therapy (VMAT), which was evaluated by dose parameters such as R 50%, homogeneity index and conformity index, etc. The results of Holter and echocardiography were monitored during the follow-up and compared with the data before treatment. Results:Three subjects with ventricular tachycardia (VT) and one with premature ventricular contraction (PVC) received the same prescription of 25 Gy in a single fraction. The average volume of PTV was 71.4 cm 3(60.3-89.4 cm 3). The average time of beam delivery was 12.0 min (4.5-21.0 min). And the short-term follow-up lasted for an average of 18 weeks (14-25 weeks), which showed significant decrease in both VT and PVC load without complications. Conclusion:This study reports the implementation method of SCRA and proves its short-term effectiveness and safety, but the effects and standards of the key radiotherapy techniques still need to be explored.

Objective:To investigate the clinicopathological features, immunohistochemical phenotypes and molecular characteristics of adenosquamous carcinoma of the lung(ASC)in elderly patients.Methods:Clinical data of 72 ASC patients in the Department of Pathology, The Second Affiliated Hospital of Soochow University from January 2009 to December 2020 were retrospectively analyzed, and 48 patients aged ≥60 years were selected.Clinical manifestations, imaging findings, histopathological and immunohistochemical characteristics were collected, and gene mutations were detected by the amplification refractory mutation system(ARMS-PCR).Results:There were 48 patients including 32 males and 16 females with a mean age of 70 years(range: 60-84 years). The maximum diameters of the tumors ranged from 0.3 to 9.0 cm(mean: 2.8 cm). Microscopically, the tumors contained two components, squamous cell carcinoma and adenocarcinoma, with the squamous cell carcinoma tissue showing intercellular bridges and the adenocarcinoma tissue showing papillary, acinar or tubular structures.Immunohistochemistry assays detected varying expression levels of CK7(30/31), CK5/6(20/28), TTF1(12/31), P40(15/17), and P63(12/13). Molecular testing showed that the EGFR mutation rate was 58.8%(10/17)and the ALK fusion mutation rate was 5.9%(1/17), while ROS1 and MET mutations were not detected.All 48 patients underwent surgical resection.Conclusions:ASC cases are relatively rare and prone to misdiagnosis.The diagnosis requires the combination of HE morphology, immunohistochemistry and imaging examination, and surgery is the main treatment option.The mutation rate of the EGFR gene is relatively high in ASC patients.

Objective:To assess the correlation between circulating chemerin and two indicators of renal function, estimated glomerular filtration rate (eGFR) and urine albumin creatinine ratio (UACR), in individuals with type 2 diabetes and to determine whether chemerin is an independent marker of early renal insufficiency.Methods:A total of 742 patients with type 2 diabetes were recruited into the cross-sectional community study. Basic information, anthropometric parameters, and biochemical parameters of these individuals were determined and collected, and serum chemerin level was measured using enzyme-linked immunosorbent assay.Results:Chemerin levels were significantly higher in the eGFR-impaired group compared with eGFR-normal group, and macroalbuminuria group compared to the normal or microalbuminuria groups. Spearman′ rank correlation analysis showed serum chemerin level was correlated with eGFR ( r=-0.25, P<0.001), UACR ( r=0.23, P<0.001) and some other biochemical indicators such as triglyceride. And univariate and multivariate logistic regression analyses revealed circulating chemerin was an independent risk factor for eGFR impairment or proteinuria after adjusting corresponding covariates. Receiver operating characteristic (ROC) curve analysis showed that the area under curve (AUC) of circulating chemerin for predicting early impaired eGFR in type 2 diabetes was 0.747, while the AUC of circulating chemerin for predicting macroalbuminuria in type 2 diabetes was 0.748. Conclusion:Circulating chemerin is associated with eGFR or UACR and may be a potential diagnostic marker for early renal insufficiency in type 2 diabetes.

Objective:To evaluate the clinical efficacy of Rotarex percutaneous mechanical thrombectomy(PMT) for treatment of lower extremity arterial graft occlusion.Methods:The clinical data of 19 patients with lower extremity arterial bypass occlusion admitted to our hospital from January 2016 to December 2020 were retrospectively analyzed. All patients were treated with Rotarex-based endovascular therapy. After 12 months follow-up, the clinical features, surgical outcomes and follow-up data were analyzed to identify effectiveness and safety of the therapy. Independent sample t test was used to analyze the measurement data of continuous normal distribution which were expressed as mean±standard deviation( ± s), enumeration data were expressed as number and percentage, and the comparison between groups were analyzed by chi-square test. Results:A technical success rate of 100% was demonstrated. Rotarex combined with catheter directed thrombolysis was performed in 2 cases, Rotarex combined with percutaneous transluminal angioplasty (PTA) was performed in 9 cases. Rotarex combined with stent implantation was performed in 8 patients. The Ankle brachial index significantly increased (0.82±0.14 vs 0.47±0.11, P<0.05). Critical limb ischemia (Rutherford class 4 or higher) improved significantly (0 case vs 9 cases, P<0.05). Distal embolism occurred in 1 patient and acute myocardial infarction occurred in 1 patient. There was no vascular rupture, haemorrhage, infection, pseudoaneurysm, death and amputation. Kaplan-Meier survival analysis revealed 12-month primary patency rate and freedom from clinically driven target lesion revascularization was 78.9% and 89.5% respectively. Conclusion:Rotarex-based endovascular therapy is a safe and effective treatment for graft occlusion after lower extremity arterial prosthesis bypass with high patency rate and few complications.

The training program of radiation therapists in the United States has been established early, and the mode of training, qualification and continuing education are relatively complete. Literature review was conducted at home and abroad and United States Department of Labor, American Registry of Radiologic Technologists, American Society of Radiologic Technologists as well as Joint Review Committee on Education in Radiologic Technology websites were reviewed. The training mode, qualification, work content, continuing education and employment situation of American radiotherapists were analyzed, aiming to provide some reference and enlightenment for the establishment of a new model for the training of professional radiologists suitable for the national conditions of China Mainland.

Objective:To investigate the relationship between serum lipocalin-2 level and the risk of cardiovascular disease(CVD) in patients with type 2 diabetes.Methods:A total of 279 type 2 diabetic patients were enrolled in this study. Basic information and clinical data were collected. These patients were divided into CVD group and non-CVD group according to their cardiovascular disease status. Serum lipocalin-2 level was assessed by enzyme linked immunosorbent assay.Results:Compared to non-CVD group, serum lipocalin-2 level was significantly higher in CVD group( P<0.01). The Spearman correlation analysis showed that serum lipocalin-2 level was positively correlated with waist circumstance, diastolic blood pressure, uric acid, triglyceride, and HbA 1C( P<0.05), while negatively correlated with high density lipoprotein-cholesterol level( P<0.01). In addition, the univariate and multivariate logistic regression analysis revealed that serum lipocalin-2 was an independent risk factor for CVD( P<0.01)after adjustment for potential confounders. Moreover, receiver operating characteristic curve analysis demonstrated that the area under curve value of lipocalin-2 was 0.74, with the optimal cutoff value of lipocalin-2 66.84 ng/mL. Conclusion:Serum lipocalin-2 is closely associated with CVD in patients with type 2 diabetes, which might be considered as one of the predictors for CVD in type 2 diabetes mellitus.

Virtual monochromatic images (VMI) that reconstructed on dual-energy computed tomography (DECT) have further application prospects in radiotherapy, and there is still a lack of clinical dose verification. In this study, GE Revolution CT scanner was used to perform conventional imaging and gemstone spectral imaging on the simulated head and body phantom. The CT images were imported to radiotherapy treatment planning system (TPS), and the same treatment plans were transplanted to compare the CT value and the dose distribution. The results show that the VMI can be imported into TPS for CT value-relative electron density conversion and dose calculation. Compared to conventional images, the VMI varies from 70 to 140 keV, has little difference in dose distribution of 6 MV photon treatment plan.
Electrons ; Phantoms, Imaging ; Tomography Scanners, X-Ray Computed ; Tomography, X-Ray Computed

Objective:To establish a dental fluorosis model of SD rats with various degrees, to observe the microstructures of enamel samples under scanning electron microscope and to clarify the changes of enamel microstructures with various degrees of dental fluorosis, so as to provide clinical reference for the treatment of patients with moderate and severe dental fluorosis.Methods:Thirty male SD rats (6 weeks of age) were randomly divided into 3 groups with 10 rats in each group. The control group was fed with deionized water without fluoride, the low fluoride group was fed with 50 mg/L NaF deionized water and the high fluoride group was fed with 100 mg/L NaF deionized water in order to establish the dental fluorosis model of rats. After feeding for 6 weeks, the rats were sacrificed and the mandibular incisor teeth were collected and recorded. The surface and sagittal plane of each tooth were observed by scanning electron microscopy and the enamel thickness was measured.Results:In the control group, the enamel color was brown yellow. Enamel color discoloration occurred both in low-fluoride group and high-fluoride group. The enamel color in low-fluoride group was mostly yellow and white striped while in high-fluoride group was mostly chalky white. Under electronic microscope, the enamel rods were alternately arranged and their structure was clear and plump in the control group. The enamel rods of moderate fluorosis were arranged in a straight orientation like tips of bamboo shoots. The enamel rods of severe fluorosis, however, became thinner and the tips of rods were broken. In the control group, sagittal images of enamel turned out to be a dense outer structure with clear boundaries among the inner. The structure of the middle layer was reticulated showing a clear boundary with middle and outer layers. The structure of enamel rods in the inner layers was arranged vertically and horizontally. In the moderate fluorosis group, the outer layer of the enamel became thinner and the middle layer disappeared although the boundary between the outer and middle layers was still clear. In the inner layer, the vertically arranged enamel rods seemed still clear, however the horizontal enamel rods disappeared. In the severe fluorosis group, the outer layer could not be traced. The middle layer was exposed to the air and the inner enamel rods contracted. The inner layers of the enamel had gradually become thinner with the development of the dental fluorosis. The thicknesses of inner layers in control, moderate and the severe groups were (180.71 ±7.01), (157.10 ±11.04) and (121.10 ±12.56) μm respectively. As for the thicknesses of the full layers in the above mentioned three groups, the same trend was observed. The thicknesses, in order of the severity of dental fluorosis, were (241.54 ±7.76), (207.42 ±14.36) and (143.79 ±14.60) μm. Conclusions:With the development of dental fluorosis, the outer enamel layers became thinner or disappeared and the inner enamel layers became thinner or lost its normal structure as well. It is highly recommended that the resin penetration could be used for the proper treatment of moderate and severe dental fluorosis and the strong bleaching and the micro-grinding should be used cautiously.

Objective:To evaluate the safety and efficacy of a combination of percutaneous mechanical thrombectomy (PMT) and drug coated balloon(DCB)for the treatment of in-stent restenosis(ISR) and arterial thrombosis of the lower extremity.Methods:The clinical data of 53 patients treated with PMT + DCB were analyzed retrospectively, including 38 cases of ISR and 15 cases of arterial thrombosis. 33 patients were males and the others were females , the mean age was (68.6±9.4) years . Patients were followed at 30 days, 6 months, and 12 months concerning clinical symptoms, calculation of ABIs and duplex ultrasonography.Results:Procedural success was achieved in all 53 patients. One patient died of cardiovascular event perioperatively. 6 operation-related complications occurred including 5 cases of distal embolism during the PMT managed by using 5 F angiography catheter suction and one case of artery perforation during PMT procedure, a balloon was used to cover it. 47 (88.6%) patients completed 12-month follow-up, the TLR was 10.6% (5/47). One patient had the amputation 4 months later; There were 7 cases with arterial restenosis.PMT+ DCB were performed again in 4 cases, 1 case received stent implantation and 2 cases treated by medication.Conclusion:The use of combination of PMT and DCB is a safe and effective method to treat ISR and arterial thrombosis of the lower extremity.