The prevalence of diabetes mellitus in China has recently been increasing year by year,and spontaneous skin ulcers in diabetic patients,as one of the most serious complications,often develop on the patient's extremities represented by foot ulcers.Due to the complexity and variety of its pathogenesis,it leads to poor clinical outcomes and difficulty in healing.Thus,pa-tients often face the risk of amputation and death.Therefore,the exploration of mechanisms of the vascular pathogenesis of diabetic delayed-healing wounds and targeted screening of therapeutic agents has become a current research hotspot.Herein,in this paper,we briefly review the role of impaired angiogenesis and vascular dysfunction in diabetic skin ulcers,and the research progress of classical hypoglycemic and natural compounds against vascular lesions is preliminarily summarized to provide a theoretical basis for effective clinical treatment.

Objective:To conduct a statistical analysis on the condition of patients with pneumoconiosis complicated with chronic pulmonary heart disease based on the Tei index, and to establish a relevant prediction model.Methods:In March 2022, a retrospective analysis of 226 patients diagnosed with pneumoconiosis in the Department of Occupational Disease of Yantai Yantaishan Hospital from January 2016 to January 2022 was conducted. The patients with pneumoconiosis complicated by pulmonary heart disease were included in the pulmonary heart disease group and others were included in the non-pulmonary heart disease group. logistic regression analysis was used to screen out the relevant factors and establish a risk prediction model. Hosmer-Lemeshow test was applied to determine the goodness of fit of the model, and the receiver operating characteristic (ROC) area under the curve (AUC) was used to evaluate the predictive effect of the model.Results:Among the 226 patients with pneumoconiosis, 58 patients had chronic pulmonary heart disease, accounting for 25.7% of the surveyed population. The logistic analysis showed that the course of disease, pneumoconiosis stage and Tei index were influencing factors of pneumoconiosis complicated with pulmonary heart disease ( P<0.05). A risk prediction model for pneumoconiosis patients complicated with pulmonary heart disease was developed: Z=6.253 X1+1.265 X2+1.423 X3+9.264, in which X1 was the stage of pneumoconiosis, X2 was the course of disease, and X3 was the Tei index. Hosmer-Lemeshow test was used to evaluate the goodness of fit of the risk prediction model for pneumoconiosis patients complicated with pulmonary heart disease, the results indicated that the prediction model was in good agreement with the actual situation (χ 2=11.59, P=0.254). The diagnostic ability of the model was evaluated by the ROC curve, and the results showed that its AUC was 0.897, the sensitivity was 0.947, and the specificity was 0.784. Conclusion:The course of disease, pneumoconiosis stage and Tei index are the influencing factors of pneumoconiosis complicated with pulmonary heart disease. The model constructed based on these factors has a good prediction effect, which can provide a basis for the early detection and intervention of pneumoconiosis complicated with pulmonary heart disease.

Objective:To conduct a statistical analysis on the condition of patients with pneumoconiosis complicated with chronic pulmonary heart disease based on the Tei index, and to establish a relevant prediction model.Methods:In March 2022, a retrospective analysis of 226 patients diagnosed with pneumoconiosis in the Department of Occupational Disease of Yantai Yantaishan Hospital from January 2016 to January 2022 was conducted. The patients with pneumoconiosis complicated by pulmonary heart disease were included in the pulmonary heart disease group and others were included in the non-pulmonary heart disease group. logistic regression analysis was used to screen out the relevant factors and establish a risk prediction model. Hosmer-Lemeshow test was applied to determine the goodness of fit of the model, and the receiver operating characteristic (ROC) area under the curve (AUC) was used to evaluate the predictive effect of the model.Results:Among the 226 patients with pneumoconiosis, 58 patients had chronic pulmonary heart disease, accounting for 25.7% of the surveyed population. The logistic analysis showed that the course of disease, pneumoconiosis stage and Tei index were influencing factors of pneumoconiosis complicated with pulmonary heart disease ( P<0.05). A risk prediction model for pneumoconiosis patients complicated with pulmonary heart disease was developed: Z=6.253 X1+1.265 X2+1.423 X3+9.264, in which X1 was the stage of pneumoconiosis, X2 was the course of disease, and X3 was the Tei index. Hosmer-Lemeshow test was used to evaluate the goodness of fit of the risk prediction model for pneumoconiosis patients complicated with pulmonary heart disease, the results indicated that the prediction model was in good agreement with the actual situation (χ 2=11.59, P=0.254). The diagnostic ability of the model was evaluated by the ROC curve, and the results showed that its AUC was 0.897, the sensitivity was 0.947, and the specificity was 0.784. Conclusion:The course of disease, pneumoconiosis stage and Tei index are the influencing factors of pneumoconiosis complicated with pulmonary heart disease. The model constructed based on these factors has a good prediction effect, which can provide a basis for the early detection and intervention of pneumoconiosis complicated with pulmonary heart disease.

Objective:To explore the value of high frequency ultrasound combined with serum alpha-fetoprotein (AFP) in the accurate qualitative diagnosis of pediatric testicular tumors.Methods:The ultrasound characteristics (physical properties, calcification, alder blood flow classification) and AFP levels of 47 testicular tumors confirmed by operation and pathology were analyzed retrospectively. The tumors were further divided into two ways: malignant tumor group and benign tumor group, yolk sac tumor group and non yolk sac tumor group. The characteristics of ultrasound and the accurate qualitative diagnosis efficiency of AFP in testicular tumors were analyzed by receiver operating characteristic curve (ROC).Results:18 cases of yolk sac tumor showed solid or almost solid mass, which may be accompanied by several small anechoic areas without calcification. The Alder blood flow grade were grade 3. 29 cases of nonyolk sac tumor showed cystic, solid or mixed mass, most of them have calcification and some of them showed honeycomb echo. Alder blood flow grade were 0-3 grade. ROC curve analysis showed that the area under the curve, sensitivity and specificity of the ultrasound characteristics and AFP in the diagnosis of pediatric testicular malignancies were: solid or almost solid mass (0.894, 83.3%, 95.5%), and no calcification (0.904, 94.4%, 86.4%), Alder blood flow level 3 (0.941, 88.9%, 95.5%), AFP by best cut-off value 18.8 ng/ml (0.972, 100%, 95.5%), ultrasound features combined with AFP (0.992, 100%, 90.9%). All the testicular malignancies, such as yolk sac tumor, immature teratoma, teratoma combined with yolk sac tumor, can be identified by ultrasound features combined with AFP. Further analysis showed that the sensitivity and specificity of the diagnosis of yolk sac tumor with combined solid or almost solid and no calcification were both 100.0%, which can accurately distinguish all cases of yolk sac tumor.Conclusions:Pediatric testicular yolk sac tumor has specific ultrasound performance, high-frequency ultrasound can make a relatively accurate diagnosis, combined with serum AFP can further make a relatively accurate qualitative diagnosis of other malignant tumors of the testis in children.

Genome packaging is a fundamental process in a viral life cycle and a prime target of antiviral drugs. Herpesviruses use an ATP-driven packaging motor/terminase complex to translocate and cleave concatemeric dsDNA into procapsids but its molecular architecture and mechanism are unknown. We report atomic structures of a herpesvirus hexameric terminase complex in both the apo and ADP•BeF3-bound states. Each subunit of the hexameric ring comprises three components-the ATPase/terminase pUL15 and two regulator/fixer proteins, pUL28 and pUL33-unlike bacteriophage terminases. Distal to the nuclease domains, six ATPase domains form a central channel with conserved basic-patches conducive to DNA binding and trans-acting arginine fingers are essential to ATP hydrolysis and sequential DNA translocation. Rearrangement of the nuclease domains mediated by regulatory domains converts DNA translocation mode to cleavage mode. Our structures favor a sequential revolution model for DNA translocation and suggest mechanisms for concerted domain rearrangements leading to DNA cleavage.

Objective:To investigate the clinical significance of preserving supraclavicular nerve in the reduction and fixation of clavicular fracture.Methods:A retrospective study was conducted of the 68 pa-tients with clavicular fracture who had been treated surgically from October 2016 to April 2018 at Department of Orthopedics and Traumatology, Heyuan Hospital of Traditional Chinese Medicine.They were 35 males and 33 females, aged from 25 to 45 years (average, 34.8 years).The supraclavicular nerve was preserved in the re-duction and fixation of clavicular fracture in 32 patients (reservation group) but not in the other 36 ones (control group).The 2 groups were compared in terms of operation time, intraoperative blood loss, fracture healing time; postoperative pain tolerance, feeling (by the British Medical Research Council assessment), shoulder function (by the Constant-Murley scoring) and impact of numbness on life.Results:The 2 groups were compatible due to insignificant differences in the general clinical data between them ( P>0.05).All the 68 patients were followed up for 12 to 26 months (average, 15 months).There was no significant difference between the 2 groups either in intraoperative blood loss or fracture healing time ( P>0.05).The preservation group had significant longer operation time (72.6 min±7.2 min) than the control group (47.3 min±7.4 min), but a significantly lower rate of analgesic usage on the postoperative day [6.3%(2/32)] than the control group [91.7%(33/36)] (both P<0.05).By the British Medical Research Council assessment, the postoperative feeling was rated as S3 or S4 in 93.8%(30/32) of the patients in the preservation group, significantly higher than the 72.2% (26/36) of the control group ( P<0.05).The preservation group was also significantly better than the control group in Constant-Murley scores of the injured shoulder [100.0 (93.5, 100.0) versus 87.0 (81.0, 89.0)] and impact of numbness on life [0 versus 50.0%(18/36)] (both P<0.05). Conclusion:In surgical treatment of clavicular fracture, preservation of the supraclavicular nerve can have a positive effect on reducing postoperative pain in the operative area and impact of numbness on life.

Objective:To investigate the application value of high-frequency linear array probe in prenatal ultrasound diagnosis of fetal kidney fusion anomalies.Methods:A senior sonographer for prenatal diagnosis used a convex array probe and a high-frequency linear array probe to obtain and store renal images of the transverse section, sagittal and coronal plane and ectopic kidney of 27 fetuses with suspected or diagnosed fetal renal fossa emptiness, abnormal renal position and abnormal renal contour in Guangdong Women and Children Hospital from December 2018 to October 2019. The images were analyzed to judge the possibility of kidney fusions by another senior sonographer (subject 1) and a junior sonographer (subject 2) separately. Then, ROC curves were plotted and statistically analyzed based on postnatal follow-up results. The Kappa coefficient between the two subjects was calculated.Results:Areas under the two ROC curves were 0.969 and 0.756 when using a convex array probe, but 1.000 and 1.000 with a high-frequency linear array probe by two subjects separately. Subject 1 had no significant difference using two kinds of probes ( P>0.05), however, subject 2 had higher diagnostic accuracy when using high frequency linear array probes ( P<0.05). The diagnostic consistence of high-frequency linear array probe between subjects was higher than convex array probe, the Kappa coefficients were 1.000 and 0.516, respectively. Conclusions:The application of high-frequency linear array probe in prenatal diagnosis of fetal kidney fusion anomalies is feasible, and can improve the confidence and diagnostic accuracy for fetal kidney fusion anomalies.

Objective Studies have shown that problem based learning (PBL) can improve the students' ability of autonomous learning.However,it is unclear whether students' autonomous learning ability will affect students' evaluation in PBL teaching.This study took medical psychology course as an example to explore the influence of medical students' autonomous learning ability on PBL teaching effect.Methods 43 8-year program medical students of Grade 2010 and 2011 were enrolled in this study.Scale was used to assess medical students' autonomous learning ability before the start of the PBL teaching.Self made questionnaire was used to survey the students' evaluation in PBL teaching.Linear correlation analysis was used to detect the relationship between medical students' autonomous learning ability and students' evaluation in PBL teaching and their examination results.Results Medical students' autonomous leaming ability is significantly positively correlated to the students' evaluation of PBL teaching (P＜0.05).The correlation coefficient between learning motivation and "PBL enhanced learning interest" or "PBL enhanced information utilization ability" was high (r=0.507 and 0.536,respectively).It showed that students with stronger autonomous learning ability had more positive evaluation of PBL teaching.The students' learning motivation was also positively correlated to the test score (r=0.416,P=0.006).Students with stronger learning motivation had higher test score in the final exam.Conclusion These results indicate that the relationship between the students' autonomous learning ability and PBL teaching is bidirectional.The students with more powerful ability of autonomous learning will be more active in the process of PBL teaching,and the positive experience will promote their autonomous learning ability in turn.

Objective To discuss the diagnostic value of 3D-ultrasound for cord entanglement in monoam-niotic twins. Methods From November 2013 to March 2016,a total of 65 monoamniotic twinsunderwent routine obstetric ultrasonography to screen fetal abnormalities in our hospital. The cord was meticulously observedusing a systematic continuous sequence approach. Fetuses who showed cord entanglement by 2-D ultrasound or 3-D flow Doppler were all recruited. The gestational weeks,fetal malformation,ultrasonic image feature of cord entangle-ment,and clinicaloutcome were recorded and analyzed retrospectively. Results 4 monoamniotic twins showed cord entanglement. Three-dimensional color Doppler clearly delineated thefeatures of entanglement. At following-up of 8 fetuses,3 fetuses were found intrauterine fetal death and 3 fetuses with structural abnormalities except for 2 well infants.Conclusion Cord entanglement may threaten the safety of fetusesin monoamniotic pregnancies.In aid of 2-D ultrasound or 3-D flow Doppler in monoamniotic twins can help to find it in time ,monitor it carefully and provide evidence for obstetric treatment .

Objective To explore ultrasonographic characteristics and prognosis of cesarean scar pregnancy in the ultrasound.Methods To conducted a retrospective study of 8 cases of diagnoses of cesarean scar pregnancy in ultrasound in our hospital from January 2013 to August 2015.All cases had ultrasonographic examinations regularly during the pregnancy and were confirmed placenta increta by cesarean section or prenatal MRI (6 cases).The imaging characteristics of 8 cases of pregnant women in early pregnancy by transvaginal ultrasound,and the positions of gestational sac and chorion frondosum were observed.Ultrasonic follow-up results,numbers of cesarean delivery,final diagnosis,and pregnancy outcome were analyzed.Results Eight cases of patients were diagnosed cesarean scar pregnancy,and all of ceses were diagnosed placenta increta by ultrasound from 11 weeks to 24 weeks of gestation.It was found that the positions of chorion frondosum were located in the lower edge of gestational sac in Two-dimensional ultrasound and the chorion frondosum was covered in cesarean section scar.The echoes of proliferous chorion frondosum were stronger than the rest of chorion leve and decidua reflexa,and the thickness of proliferous chorion frondosum were thicker than the rest of chorion leve and decidua reflexa.In the follow-up ultrasound of 8 cases in the second trimester,the original position of chorion frondosum which covered and the position of placenta were roughly similar.The position of placenta did not move up with the gestational weeks,in addition,appeared as placenta previa and covered in cesarean section scar.Five patients had strong childbearing willing of continue to conceive,one case of which needed hysterectomy,four of which underwent cesarean section delivery with alive births after using bilateral iliac arteries balloon occlusion.The rest 3 cases underwent induction of labor after using bilateral iliac arteries balloon cclusion.Conclusions Cesarean scar pregnancy in first pregnancy may be develop as placenta accreta in second and third trimester pregnancy.If chorion frondosum was observed to cover cesarean section scar by ultrasound in early pregnancy,scar pregnancy diagnosis was established.Pregnant women who have strong willing to continue their pregnancy should be pay more attentin to thiers placenta previa and placenta percreta in second and third trimester pregnancy.Close follow-up are needed.