Background and purpose:Life expectancy has continuously improved in recently years with the development of medical level. In 2012, the amount of people who were above 60 years old has reached 810 million and account for 11% of worldwide population. The worldwide population shift towards older ages will inevitably lead to more elderly patients being diagnosed with non-small cell lung cancer (NSCLC). It still remains controversial whether sublobar resection is effective in such cases. In order to solve this question, we need to understand the clinical characteristics of these tumors. Methods:From 2006 to 2012, a total of 310 patients with NSCLC who were above 65 years old underwent surgical resection in Department of Thoracic Surgery, the First Afifliated Hospital of China Medical University and the Second Department of Thoracic Surgical Oncology, Jilin Province Tumor Hospital. The clinical data were retrospectively analyzed in sex, stage, histology, smoking status, smoking amount, drinking status, surgical approaches, multimodality therapy and overall survival. Survival was analyzed by Kaplan–Meier method and log-rank test. Results:There were 256 (82.6%) elderly patients who underwent standard lobectomies and 54 (17.4%) patients who underwent sublobar resections. The overall 5-year survival rate was 52.9%. Patients with different surgical approaches (lobectomy and sublobar resection) had nearly the same 5-year survival rates (60.5%vs 60.8%, P=0.381). The prognosis were signiifcantly inlfuenced by gender (P=0.024), stage of disease (P=0.028), smoking status (P=0.034) and smoking amount (P=0.028). The multivariate Cox proportional hazards analysis revealed that the smoking status was associated with the hazard ratio of 1.660 (1.058-2.606;P=0.028). Conclusion:In elderly NSCLC patients, sublobar resection is considered to be an appropriate treatment in comparison with lobectomy, as this procedure provides an equivalent long-term survival. The survival of elderly patients with lung cancer is closely related to the smoking status.

Objective To determine the optimal procedure for preparation of the SPIO nanoparticles modified by dextran polylysine,and to evaluate the quality of this product.Methods The optimal preparation procedure of four factors (solution pH value,dextran concentration,reaction temperature and stirring rate) affecting SPIO hydrodynamic size were obtained through orthogonal experiments (3 levels).SPIO nanoparticles were synthesized under an optimum procedure.The shape and hydrodynamic size were detected by transmission electron microscope (TEM) and Malvern Zetasizer respectively.The content of Fe was detected by atomic absorption spectrophotometer,while chemical structures of SPIO nanoparticles were characterized and analyzed by infrared spectroscopy (IR) method.X-ray powder diffraction method was used to identify the ingredients,and the magnetic parameters were measured by vibrating sample magnetometer.Furthermore,experiments with ovarian cancer cells were performed to primarily validate the magnetic property of SPIO nanoparticles.Results The results of the orthogonal experiments showed that the optimum preparation procedure was as follows:dextran concentration of 10 mg/ml,pH 10,reaction temperature of 80 ℃ and stirring rate of 600 r/min.The TEM results showed the SPIO nanoparticles were in spherical shape,homogeneously distributed and uniform in size,and the mean diameter was 7.0 nm.The content of Fe was (12.36±0.08) g/L.The IR results clearly showed that the Fe3O4 was coated by dextran successfully.The Xray powder diffraction method showed that the sample contained Fe3O4 and the magnetism parameters indicated that the sample had superparamagnetism.The experiments with ovarian cancer cells demonstrated that SPIO nanoparticles could enter into the cells and then the cells had certain magnetic properties.Conclusions The SPIO nanoparticles synthesized under the optimal procedure are stable,small in size,with good dispersion and are feasible to enter into cells for rendering certain magnetic properties.This study has provided a good foundation and potential for further research.

Objective To investigate the promotion effect of human transcriptional positive cofactor 4 (PC4) overexpression on lymphatic metastasis in lung adenocarcinoma .Methods 96 samples of lung adenocarcinoma tissue were collected .The immuno‐histochemistry(IHC) and real‐time quantitative polymerase chain reaction (qRT‐PCR) were adopted for detecting the expression levels of PC4 protein and mRNA .The correlation of PC4 expression with lymphatic metastasis and TNM stage was analyzed .Re‐sults The expression of PC4 protein was positively correlated mRNA in lung adenocarcinoma (r=0 .63 ,P<0 .01);the expression of PC4 protein was positively correlated with lymph node metastasis (χ2 =8 .29 ,P<0 .01) and TNM stage (χ2 =4 .71 ,P<0 .05);the expression of PC4 mRNA was also positively correlated with lymph node metastasis (χ2 = 8 .40 ,P< 0 .01) and TNM stage (χ2 =5 .10 ,P<0 .05) .Conclusion PC4 overexpression is found to be closely associated with the lymph node metastasis and TNM stage .PC4 may facilitate the lymph node metastasis of lung adenocarcinoma .

Objective To compare the value of assessment with DWI and contrast-enhanced MRI (CE-MRI) in activity of sacroiliitis of patients with ankylosing spondylitis(AS).Methods Ninety-six patients conforming to modified New York criteria were prospectively collectedas the AS group, and twenty-one healthy volunteers were enrolled into the control group. According to the Bath AS disease activity index (BASDAI), erythrocyte sedimentation rate and C-reaction protein, AS patients were divided into the active AS group (n=60) and the chronic AS group (n=36) . All subjects were performed with conventional MRI, DWI and CE-MRI of bilateral sacroiliac joints. The MRI manifestations were reviewed and the ADC values and signal intensity enhancement rate (ΔSI) were measured.ANOVA was performed for the comparison ofΔSI and ADC values among active AS group, chronic AS group and control group with BASDAI and lab test results as the gold standards. ROC was analyzed with ΔSI and ADC values for activity of AS and paired
samples t test was obtained to comparethe areas under the ROC ofΔSI and ADC values.Results Among 96 cases of AS patients, MRI of sacroiliac jointsshowed that 62 cases had subchondral bone edema (57 cases of active group, 5 cases of chronic group), that 11 cases had bone surface erosion(4 cases of active group, 7 cases of chronic group), that 15 cases had bone sclerosis(6 cases of active group, 9 cases of chronic group) and that 58 cases had fat deposition on the sacroiliac joints (27 cases of active group, 31 cases of chronic group). The ΔSI values of the active group, the chronic group and control group were respectively (2.51 ± 1.69)%,(1.19 ± 0.67)%and(0.75 ± 0.21)%, and the ADCvalues were(1.33 ± 0.33)× 10-3,(1.00 ± 0.43)× 10-3 and(0.38±0.13)×10-3mm2/s. There were significant differences forΔSI and ADC values among three groups (F=18.375, 16.366. P<0.01), and statistical significance ofΔSI and ADC values were found between every two groups of three(P< 0.05).The area under the ROC between ΔSI and ADC to determine activity of AS patients were respectively 0.814 and 0.730, which had nostatistical significance(t=1.632, P=0.103). The sensitivity and specificity to determine activity of AS patients byΔSI=1.44%were 81.67%and 80.00%.The sensitivity and specificity to determine activity of AS patients by ADC=1.15 × 10-3/mm2 were 76.67% and 71.43%.Conclusion DWI and CE-MRI performed equally in detecting activity of AS patients.

Objective: To evaluate the relationship between the offset of a laser-assisted flap using the WaveLight FS200 femtosecond laser and the clinical results after femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK). Methods: In this prospective cohort study, 125 patients who underwent FS-LASIK for myopia by WaveLight FS200 femtosecond laser from June 2017 to July 2018 at the Tungwah Ophthalmic Center were divided into two groups according to the offset of the corneal flap from the pupil center: the no-offset group (57 eyes) and the certain-offset group (68 eyes); the baseline data, including age, sex, uncorrected visual acuity(UCVA), spherical degree, and central corneal thickness were matched in the two groups.UCVA, residual astigmatism, spherical degree, corneal curvature and aberration were observed 1 week and 1 month after surgery.The study protocol was approved by the Ethics Committee of Tungwah Hospital of Sun Yat-Sen University (No.2017DHLL004). Written informed consent was obtained from each subject prior to entering the study cohort. Results: UCVA, corneal curvature, spherical degree, spherical and corneal aberration between the two groups were not significantly different (all at P>0.05). One week after surgery, the residual astigmatism was ≤-0.50 D in 50 eyes (87.7%, 50/57)and >-0.50 D in 7 eyes (12.3%, 7/57) in the no-offset group; the residual astigmatism was ≤-0.50 D in 50 eyes (73.5%, 50/68) and >-0.50 D in 18 eyes (26.5%, 18/68) in the no-offset group.The residual astigmatism between the two groups 1 week after surgery was significantly different (χ²=3.902, P=0.048), and there was no significant difference in residual astigmatism 1 month after surgery (χ²=2.031, P=0.068). The trefoil of the no-offset group was statistically less than of the certain-offset group at 1 week and 1 month after surgery (0.05[0.04, 0.08]vs.0.06[0.04, 0.10]; 0.05[0.03, 0.07]vs.0.06[0.05, 0.09])(Z=-2.245, P=0.022; Z=-2.370, P=0.018). The spherical aberration and coma were not significantly different between the two groups at 1 week and 1 month after surgery (both at P>0.05). Conclusions The offset from femtosecond laser-assisted flap by WaveLight FS200 has no effect on long-term visual acuity or residual astigmatism.Some patients may have different visual experiences because of the residual astigmatism and higher order aberration during the early postoperative stage.

Objective To ensure the effectiveness and improve the capacity of laboratories in the measurement of γ spectra of radionuclides. Methods A statistical analysis was performed using relative deviation, accuracy, precision, and relative combined uncertainty for the nationwide assessment of radionuclide γ spectrum measurement. Results In the assessment from 2018 to 2020, our laboratory showed qualified or above results, and the performance in 2019 was excellent. The maximum relative deviation of 11 measurements from 2018 to 2020 was 18.01%. The assessment showed |Z_test|≤1 and U_test≤2.58 in 2018, |Z_test|≤1 and U_test≤1 in 2019, and U_test≤1 and U_rel≤20% in 2020. Conclusion Our laboratory employs the correct method for radionuclide γ spectrum measurement, and the analysis data are accurate and reliable.

OBJECTIVE: To develop and validate radiomics models based on non-enhanced magnetic resonance (MR) imaging for differentiating chondrosarcoma from enchondroma. METHODS: We retrospectively evaluated a total of 68 patients (including 27 with chondrosarcoma and 41 with enchondroma), who were randomly divided into training group (=46) and validation group (=22). Radiomics features were extracted from TWI and TWI-FS sequences of the whole tumor by two radiologists independently and selected by Low Variance, Univariate feature selection, and least absolute shrinkage and selection operator (LASSO). Radiomics models were constructed by multivariate logistic regression analysis based on the features from TWI and TWI-FS sequences. The receiver-operating characteristics (ROC) curve and intraclass correlation coefficient (ICC) analyses of the radiomics models and conventional MR imaging were performed to determine their diagnostic accuracy. RESULTS: The ICC value for interreader agreement of the radiomics features ranged from 0.779 to 0.923, which indicated good agreement. Ten and 11 features were selected from the TWI and TWI-FS sequences to construct radiomics models, respectively. The areas under the curve (AUCs) of TWI and TWI-FS models were 0.990 and 0.925 in training group and 0.915 and 0.855 in the validation group, respectively, showing no significant differences between the two sequence-based models (>0.05). In all the cases, the AUCs of the two radiomics models based on TWI and TWI-FS sequences and conventional MR imaging were 0.955, 0.901 and 0.569, respectively, demonstrating a significantly higher diagnostic accuracy of the two sequence-based radiomics models than conventional MR imaging (<0.01). CONCLUSIONS The radiomics models based on TWI and TWI-FS non-enhanced MR imaging can be used for the differentiation of chondrosarcoma from enchondroma.
Chondroma ; Chondrosarcoma ; Humans ; Magnetic Resonance Imaging ; ROC Curve ; Retrospective Studies

ObjectiveTo assess the microstructural involvement of gray matter in recovered COVID-19 patients using Synthetic MRI. MethodsThis study was conducted in 29 recovered COVID-19 patients， including severe group （SG， n=11） and ordinary group （OG， n=18）. Healthy volunteers matched by age， sex， BMI and years of education were selected as a healthy control group （HC=23 cases）. Each subject underwent synthetic MRI to generate quantitative T₁ and T₂ maps， and the T₁ and T₂ maps were segmented into 90 regions of interest （ROIs） using automatic anatomical labeling （AAL） mapping. T₁ and T₂ values for each ROI were obtained by averaging all voxels within the ROIs. The T₁ and T₂ values of the 90 brain regions between the three groups were compared. ResultsRelative to HC， the SG had significantly higher T2 values in bilateral orbital superior frontal gyrus， bilateral parahippocampal gyrus， bilateral putamen， bilateral middle temporal gyrus， bilateral Inferior temporal gyrus， left orbital superior frontal gyrus， left orbital inferior frontal gyrus， left gyrus rectus， left anterior cingulate and paracingulate gyri， right median cingulate and paracingulate gyri， left posterior cingulate gyrus， and left supramarginal gyrus （P＜0.05）； Relative to OG， SG showed significantly increased T₂ values in the left rectus gyrus， left parahippocampal gyrus， bilateral middle temporal gyrus， and bilateral inferior temporal gyrus （P＜0.05）. Relative to HC， the T₁ values of SG were significantly increased in bilateral orbital superior frontal gyrus， left rectus gyrus， left anterior cingulate and paracingulate gyri， right posterior cingulate gyrus， left parahippocampal gyrus， left lingual gyrus， left putamen， left thalamus（P＜0.05）； Relative to OG， the T₁ values of SG were significantly higher in the right posterior cingulate gyrus， right calcarine fissure and surrounding cortex， and left putamen （P＜0.05）. ConclusionsEven after recovering from COVID-19， patients may still have persistent or delayed damage to their brain gray matter structure， which is correlated with the severity of the condition. SyMRI can serve as a sensitive tool to assess the extent of microstructural damage to the central nervous system， aiding in early diagnosis of the disease.

Objective To improve the analysis of ¹³⁴Cs, ¹³⁷Cs, and ⁶⁰Co in aerosol samples by the national key radiation environment laboratories. Methods Intercomparison of analysis results of ¹³⁴Cs, ¹³⁷Cs, and ⁶⁰Co in standard aerosol samples was performed among the national key radiation environment laboratories according to Gamma spectrometry method of analyzing radionuclides in biological samples (GB/T 16145-1995 ), and the intercomparison results were evaluated by the standard deviation. Results Six laboratories were involved in the intercomparison. For ¹³⁴Cs, 50% of the laboratories showed a relative deviation less than 10%, and 50% showed a relative deviation of 10%-20%. For ¹³⁷Cs, 33.3% of the laboratories showed a relative deviation less than 10%, and 76.7% showed a relative deviation of 10%-20%. For ⁶⁰Cs, all laboratories showed a relative deviation less than 10%. The overall intercomparison results were acceptable. Conclusion The laboratories in this intercomparison show generally good results.

Objective: To explore the factors, characteristics and imaging manifestations of ankle joint injury in amateur marathoners (no formal training and no marathon career). Methods: From December 2018 to March 2019, the amateur marathon runners in Guangdong Zhuhai had been recruited as research subjects according to the study inclusion and exclusion criteria. The questionnaires were used to collect relevant data, and the subjects underwent MRI scans of the ankle joint. The ankle joint special phased array coils were used to perform fast spin echo sequence (TSE) coronal T₁WI and proton density-weighted fat-suppression sequence (PDWI-FS). Axial, coronal and sagittal scans, three-dimensional-double echo steady-state sequence (3D-DESS) and three-dimensional variable flip angle fast spin echo sequence (3D-SPACE) scans were also acquired. The results of the examination were independently analyzed by two radiologists (5 and 17 years of work experience, respectively) on the ligament, tendon, bone marrow and ankle joint injuries. When they had inconsistent views, the diagnosis provided by the third radiologist (27 years of work experience) was considered a final diagnosis. The relationship between ankle injury and different running postures, the number of participating in marathons and training intensity was analyzed, and the independent sample χ² was used for statistical analysis. The consistency of two radiologists was tested by Kappa test. Results: According to the inclusion and exclusion criteria, 39 subjects were included, with 64 ankles totally, 35 right ankles and 29 left ankles. MRI showed that (1) Ligament injuries: 28 ankles were anterior talofibular ligament injuriy;50 ankles were posterior talofibular ligament injury; 60 ankles the calcaneofibular ligament injuries and 54 ankles were deltoid ligament injuries, without complete injury. (2) Tendon sheath effusion and injuries: peritendinous effusion was common, with 47 flexor hallucis longus tenosynovitis, 49 posterior tibialis tenosynovitis, 37 flexor digitorum longus tenosynovitis, 7 peroneus longus tenosynovitis and 5 peroneus brevis tenosynovitis. (3) Synovitis effusion: 43 posterior ankle synovitis and local effusion. (4) Others: cartilage injury in 2 ankles, bone marrow edema in 8 ankles, and among them stress fracture in 2 ankles. The two radiologists had good consistency with the Kappa value of 0.91. Regarding the running posture, the incidence of ligaments injuries was obviously higher in those who landed on the hind foot than in those landed on front and middle foot,and the difference was statistically significant(P=0.013, χ² value was 6.191).The incidence of tendon injuries was higher in those who landed on the front middle foot than in those landed on the hind foot, and the difference was statistically significant (P=0.029, χ² value was 4.775). Those with larger training (training running ≥300 km/month) had significant ankle injury (P=0.005, χ² value was 7.844). Conclusion The MRI features of ankle joint injuries in amateur marathon volunteers are related to different running postures and training intensity.