Polyethylene glycol (PEG) is extensively used to increasing the in vivo and in vitro stability of liposomes. However, PEGylated liposomes also produce some negative effects with further research, such as low cellular uptake, poor "endosomal escape" of pH sensitive liposome (PSL) and accelerated blood clearance (ABC) phenomenon, and this situation is referred as the "PEG dilemma". "PEG dilemma" posed severe challenges for the targeted delivery of PEGylated liposomes-loaded anticancer drugs, effective intracellular release of PEGylated PSL-encapsulated gene and protein drugs, and repeated administration of PEGylated liposomes. Therefore, it is urgent to solve the "PEG dilemma". This review focused on the definition, classification of "PEG dilemma", and discussed several possible approaches to overcome "PEG dilemma".
Antineoplastic Agents ; chemistry ; Drug Carriers ; chemistry ; Liposomes ; chemistry ; Polyethylene Glycols ; chemistry

Objective To study the value of ultrasound-guided fine needle aspiration (FNA) in the diagnosis of axillary lymph node metastasis in breast cancer,and to compared with conventional ultrasound in the diagnosis of metastatic lymph nodes of breast cancer.Methods Five hundred patients were enrolled into study prospectively from our hospital.The set of standard for patients into study:patients were diagnosed by BI-RADS and classified into class 4 or class 5 preoperative,the maximum diameter of the tumor was less than 2 cm,and there was no case of distant metastasis.Ultrasound guided FNA was performed in each case,and the results were compared with conventional ultrasound diagnosis results,using pathological findings as gold standard.Results The sensitivity,specificity,positive predictive value,negative predictive value and accuracy in the diagnosis of axillary lymph node by conventional ultrasound were 60.6%,67.6%,77.2%,48.7%,and 63.1%,respectively,and by ultrasound-guided FNA were 78%,100%,100%,71.6%,and 85.6%,respectively.There were significant differences between the two diagnostic methods statistically(χ2=113.2,P<0.001).Conclusions Ultrasound-guided FNA can effectively reduce the number of sentinel lymph node biopsy,which displays a certain clinical value.

The epidural venous plexus is considered as a cause of low back and leg pain but has been neglected for a long time. As an auxiliary drainage system of the vena cava, the epidural venous plexus plays an important role in the circulation of body fluids, and its tortuous expansion may lead to clinical symptoms similar to a herniated disc or spinal stenosis, by compressing nerve roots or dura. Due to the lack of specificity of imaging findings, it is difficult to distinguish accurately from disc herniation or spinal stenosis. The epidural venous plexus is tortuous and thin-walled, which is easy to be broken during the operation that resulted in obscuring the surgical field and leading to other complications such as postoperative hematoma. Despite researches of epidural venous plexus have been carried out for years, details are still left unknow. We hereby reviewed the latest research progress of the epidural venous plexus including anatomical structure, morphological characteristics, clinical significance and imaging examination.

Objective To discuss the clinical value of ultrasonic elastography for thyroid nodules,and compared with pathology.Methods 77 patients with 105 thyroid lesions were analyzed.Tissue stiffness on elastography was scored from one(greatest elastics train)to five (no strain).Results On elastography:scores 1 and 2 were found in 75％ benign lesions.Scores 3 to 5 were found in 97.4％ malignant lesions.There were statistically difference in the scores of elastography between the benign and malignant lesions (P ＜0.01).Conclusions The ultrasonic elastography had positive significance in differentiating benign and malignant thyroid nodules.If the score of elastography is more than or equal to 3,the thyroid nodule is highprobablely malignant.

Objective To explore the effect of entire process nursing intervention during nebulization treatment of acute wheezing episodes in school-age children.Methods One hundred and forty-one children with acute wheezing episodes were divided into the experimental group (75 patients) and the control group (66 patients) by whether willing to accept nursing intervention or not,respectively.Routine nursing such as cognition of wheezing knowledge and respiration instruction was given to both groups,while specialists accompanied the whole procedure of inhalation treatment and they gave nursing intervention such as respiration,saliva swallow,expiration through nose,grasp of inhalation tank and body position maintenance to the experimental group.The improvement of wheezing and subjective sense by the patients,transcutaneous oxygen saturation (SaO_2),and the compliance of patients were measured and evaluated.Results Improvement of wheezing and comfort feeling were found in 97.3% of the experimental group,while 80.3% of the control group.And SaO_2 value (higher than 95%) was 92.0% in the experimental group,75.8% in the control group.The compliance of the experimental group was also better than the control group.Conclusions Entire process nursing intervention during nebulization treatment can improve clinical effect and the compliance of wheezing children.

Objective To explore the advantages of Argus method by comparing the accuracy and timeliness of Argus and artificial methods for measuring femoral head necrosis area in MRI scanning.Methods Totally 17 patients (31 hips) were measured with Argus and artificial methods respectively for the necrosis area, and then the measuring results and time were compared, and the correlation was investigated between the results and the patients' pain degree, along with that between the results and the extent of femoral head collapse.Results The necrosis area ratios determined by Argus and artificial methods were (33.5±4.08)%and (34.6±4.06)%respectively, with no statistical difference between the ratios (P>0.05). The time consumed by artificial method was (21.3 ±3.62)min, significantly longer than (7.89 ±1.03)min by Argus method, with P<0.001. Regression analysis proved that the necrosis areas were positively correlated with the patients' pain degree, and the correlation coefficient by Argus method was 0.807 8, more than 0.740 9 by artificial method. The femoral heads of 11 cases(16 hips) collapsed in the follow-up period, the necrosis areas were positively correlated with the patients collapse level, but the correlation coefficient by Argus method was 0.783 8, more than 0.726 7 by artificial method.Conclusion Argus method gains high accuracy and timeliness when used in MRI scanning of femoral head necrosis area, and thus is worth popularizing clinically.

Objective:To investigate the imaging features of breast solid papillary carcinoma(SPC) by ultrasonography.Methods:The ultrasonic images of 218 breast SPC patients confirmed by pathology in Fudan University Cancer Center from December 2012 to January 2020 were retrospectively reviewed. The manifestations were preliminarily classified into 6 types, and the ultrasonic imaging features were summarized.Results:There were 22 cases with negative ultrasound findings. The cases of solid mass, nodular with ductal dilatation, cystic-solid mass, intraductal abnormal echo, simple ductal dilation and non-ductal flaky hypoechoic area or structural disorders were 79(36.2%), 33(15.1%), 29(13.3%), 30(13.8%), 20(9.2%) and 5(2.3%), respectively, and the diagnostic rates of ultrasound were 70.9%, 24.2%, 75.9%, 20%, 0 and 0, respectively.Conclusions:The ultrasonic manifestations of breast SPC are diverse, while cystic-solid findings can be seen as a clue of breast SPC.

Introduction：Neonatal tetanus is a major cause of neonatal mortality in many developing countries and remains a major public health problem. This study aimed to determine risk factors associated with neonatal tetanus in Wenzhou, China.Methodology：Medical records of neonatal tetanus cases from 17 hospitals over a 13-year period (2000–2012) were reviewed for potential risk factors. Controls were selected from neonates with diseases other than tetanus who were admitted to the same facility during the same period. The potential risk factors of the neonatal tetanus group were compared with the control group using univariate analysis and an unconditional logistic regression model.Results：A total of 246 neonates with tetanus and 257 controls were included in this study. Univariate analysis showed that having untrained birth attendants, home delivery, an unsterile method of delivery and being a migrant to Wenzhou were significantly different between the two groups (P < 0.001). Logistic regression analysis revealed that the odds of having an untrained birth attendant, home delivery and an unsterile method of delivery were significantly higher in the tetanus group than the control group (odds ratio: 1371.0; 95% confidence interval: 206.0, 9123.5).Conclusion：This study identified that the main risks of neonatal tetanus in cases from Wenzhou were having an untrained birth attendant, home delivery and an unsterile method of delivery. Preventive measures directed to these risk factors may reduce the occurrence of neonatal tetanus in the studied area.

Objective To evaluate the knowledge,attitude and practice(KAP)related with AIDS of local floating population.Methods A total of 1 942 floating persons were sampled by multistage cluster sampling and interviewed with questionnaire in the agricultural markets,construction sites,and their habitats within 3 communities in Hongkou District.Results 82.9% of the interviewees were 20 ～49 years old.The average score was 34.77 ±3.52 (maximum score is 44)for knowledge,12.11 ±2.32(maximum score is 19)for attitude,5.50 ±0.95(maximum score is 7)for practice,respectively.The scores increased with educational level significantly.The scores of knowledge were 33.26 ±3.54,34.63 ±3.23,36.56 ±3.39 among the subjects with educational levels of primary school and below,junior high school,senior high school and above.The scores of attitude were 13.77 ±2.27,14.79 ±2.39,15.62 ±2.38,respectively.And the score of practice was 5.40 ±0.90,5.51 ±0.93,5.58 ±1.03,respectively.Conclusion In the present,the KAP relating AIDS of local floating population is poor in Hongkou District.A variety of intervention methods and operational patterns should be developed for the floating population with different educational levels and jobs.

Background: Panax notoginseng saponins (PNS) are bioactive substances extracted from P. notoginseng that are widely used to treat cardiovascular and cerebrovascular diseases and interstitial diseases. PNS have the functions of scavenging free radicals, anti-inflammation, improving blood supply for tissue and so on. Objectives: The aim of this study was to investigate the effects of PNS on the oxidative stress of immune cells induced by porcine circovirus 2 (PCV2) infection in vitro and in vivo. Methods: Using an oxidative stress model of PCV2 infection in a porcine lung cell line (3D4/2 cells) and mice, the levels of nitric oxide (NO), reactive oxygen species (ROS), total glutathione (T-GSH), reduced glutathione (GSH), and oxidized glutathione (GSSG) and the activities of xanthine oxidase (XOD), myeloperoxidase (MPO) and inducible nitric oxide synthetase (iNOS) were determined to evaluate the regulatory effects of PNS on oxidative stress. Results: PNS treatment significantly reduced the levels of NO and ROS, the content of GSSG and the activities of XOD, MPO, and iNOS (p < 0.05), while significantly increasing GSH and the ratio of GSH/GSSG in infected 3D4/2 cells (p < 0.05).Similarly, in the in vivo study, PNS treatment significantly decreased the level of ROS in spleen lymphocytes of infected mice (p < 0.05), increased the levels of GSH and T-GSH (p < 0.05), significantly decreased the GSSG level (p < 0.05), and decreased the activities of XOD, MPO, and iNOS. Conclusions PNS could regulate the oxidative stress of immune cells induced by PCV2 infection in vitro and in vivo.