Objective:To elucidate the effects of Pg in modulation of monocyte adhesion to human umbilical vein endothelial cells (HUVECs).Methods:The model of infection of HUVECs by Pg was established in vitro.HUVECs were infected with Pg381 and Pg33277 and then incubated with THP-1 monocytes respectively.The amount of THP-1 adhesion to HUVECs was tested by rose Ben-gal staining assay.Results:Pg381-infected HUVECs demonstrated significantly increased adhesion of THP-1 cells compared to those infected with Pg33277(0.210 ±0.025 vs 0.078 ±0.024,P<0.05)or control HUVECs(0.062 ±0.022,P<0.05)after 6 h cul-ture.There was no differences among the above three groups after 24 h culture(P>0.05).Conclusion:The infection of Pg381 can increased the adhesion of monocytes to HUVECs.

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

Adult ; Female ; Humans ; Motor Neuron Disease ; complications ; Neck ; pathology ; Thyroid Neoplasms ; complications

Human erythropoietin receptor (hEPOR) plays an important role in regulating the red blood cell production by promoting the proliferation and differentiation of RBC from erythroid precursors, hEpoR is a transmembrane protein, and its extrocellular domain (sEpoR) is of great importance in Epo signal transduction pathway. We cloned the gene of sEpoR by RT-PCR from the total RNA of human fetal liver and expressed it in E. coli after insertion of the gene in the expression vector pBV220. The cloned gene was confirmed by sequencing analysis and gene product was confirmed by both Western blot and its first 11 amino acid residues sequence of the N-terminal. In vitro bioassay showed that the purified gene product can repress the growth of TF-cells in the presence of Epo.

It is reported that polyethylene glycol-lipid (PEG-lipid) derivatives increase liposomes stability, prolong the blood circulation of liposomes, enhance their tumor-targeting efficiency, and improve drug efficacy. Therefore, it is of great importance to investigate the influence of modified PEG-lipid derivatives on the physical, chemical, and biological characteristics of liposomes for the promotion of dealing with the existed problems, such as the accelerated blood clearance (ABC) phenomenon when repeated intravous injection at a certain time-interval, and developing novel targeted pharmaceutical preparations. In this review, the effects of modified PEG-lipid derivatives were summarized in many aspects. It indicats that the chemical bonds (amide, ether, ester, and disulfide) between PEG and lipid, as well as the species of lipids, such as the commonly used phosphatidylethanolamine, cholesterol, and diacylglycerol have substantial effects on the grafted liposomes stability in vitro and in vivo. Besides, the properties of lipids (the fatty acid chain length and saturation) and the groups (methoxy, carboxylic and amino) at the distal ends of the PEG chains were also considered to be important factors. In the end, the influence of the average molecular weight of PEG and the molar ratio of PEG-lipid derivatives in the total lipid were further focused.
Cholesterol ; chemistry ; Drug Delivery Systems ; methods ; Drug Stability ; Fatty Acids ; chemistry ; Liposomes ; chemistry ; pharmacokinetics ; Phosphatidylethanolamines ; chemistry ; Polyethylene Glycols ; chemistry

Polyethylene glycol (PEG) lipid derivatives could increase the stability of liposomes in vivo and in vitro and prolong the circulation time of liposomes in vivo. However, the chemical bond between PEG and lipid was so stable that liposomes modified with traditional PEG-lipid derivatives could not release their contents at targeted tissue immediately and the pharmacodynamic effect was reduced. The concept of cleavable PEG-lipid was raised in recent years and these PEG-lipid derivatives could break under physiological or pathological condition. The cleavable PEG-lipid derivatives could prolong the circulation time of liposomes, and after arriving at targeted location, PEG fragment had cleaved from the surface of liposomes, so liposomes could bind with pathological cells and release contents into cells. Removal of the protective polymer layer is necessary once the liposome close to the tumour to allow to fuse and release drug. Attempts have been made to increase the circulation time and reconstitute the cellular affinity of liposomes by incorporating PEG-lipid derivatives. This review focused on the kinds of cleavable PEG-lipid derivatives, types of cleavage, the application feature to liposomes and the advantages and localizations.
Cholesterol ; analogs & derivatives ; chemistry ; Drug Delivery Systems ; methods ; Humans ; Liposomes ; chemistry ; Phosphatidylethanolamines ; chemistry ; Polyethylene Glycols ; chemistry

Objective To analyze and evaluate the characteristics of cerebral sparganosis on MRI. Methods MRI appearances of 15 cases of cerebral sparganosis proven by pathology or serological test were retrospectively studied.Results A total of 21 lesions were found,some of them were single and some were multiple but asymmetrical.8 lesions were found in parietal lobe,6 in frontal lobe,2 in temporal lobe,2 in oceipital lobe,1 in basal ganglia,1 in cerebellar hemisphere and 1 in pons.The lesions carried slightly hypointense on T_1-weighted images and moderate hyperintense on T_2-weighted images.Most lesions showed pefilesional brain parenchyma edema.Enhanced MRI was performed in 10 cases,and all of them demonstrated abnormal enhancement such as peripheral ring-type,tortuous beaded shape or serpiginons tubular shape enhancement.Follow-up MR images in 6 eases were analyzed,and the location and shape of the lesions changed in 2 of them.Conclusion There are some specific MRI findings on cerebral sparganosis.Enhanced MRI and follow-up examination are important for the diagnosis of cerebral sparganosis.

Objective To compare the stability effect of the fixation segment using the new test system based robotics to simulate the complex human movement at natural state about the three-level fixa-tion by using four, five or six pedicle screws in treatment of thoracolumbar burst fractures. Methods Six human cadaveric spines were dissected from T_(11)-L_3. The inferior half part of L_1 vertebral bodies and L_1-L_2 dises were resected to mimie an unstable L_1 burst fracture with loss of anterior column support. Specimens were tested in accordance with the following order:intact, 4,5 and 6 pedicle screws fixation at the three-level fixation. The range of motion (ROM) of the fixation segment (T_(11)-L_3) was measured with the six-freedom degree robotics system controlled by mixed force and displacement during flexion, exten-sion, lateral bending and axial torsion, when the stiffness was calculated. One-way statistieal analysis was used for analyzing the collected data. Results With increased number of screws, the ROM of the fixa-tion segment (T_(11)-L_3) was gradually decreased and the stiffness gradually increased. The ROM under ax-ial rotation of six and five screws group became smaller than four screws group (P < 0.05). The stiffness under axial rotation of six screws group was higher than four screws group (P < 0.05). There was no sta-tistical difference between five screws group and four screws group in regard of the stiffness in axial rota-tion (P > 0.05). There were no significant differences in ROM and stiffness under six different loading directions between six screws group and five screws group (P > 0.05). No statistical difference was observed for three fixation modes in aspects of ROMs and stiffness under flexion-extension or lateral ben-ding (P > 0.05). Conclusions Three-level fixation of burst fractures with five or six screws offers im-proved biomechanical stability compared with traditional four screws fixation. But the difference is insig-nificant between six and five screws fixations.

Objective To explore the clinicopathological features, diagnosis and therapy for pancreatic mutinous noncystic adenocareinoma(MNAC). Methods Eleven MNAC cases treated in our hospital were studied retrospectively. The clinical and pathologic data were reviewed. Results Of the 11 patients, 6 were male and 5 were female. The age ranged from 47 to 76 years with average of 60. 5 years.The main complains included upper abdominal discomfort in 8 cases, abdominal mass in 1 case and jaundice in 2 cases. CA199 serum test was positive in all patients and 5-fold high above normal value in 6 cases. The preoperative radiography of MNAC was usually not specific. Tumors located in the head in 5 cases and in the body and tail of the pancreas in 6 cases. The diameter of the tumor was 4 - 11 cm with average of 6. 5 cm.All cases underwent operation, with radical resection in 2 cases. Liver or abdominal metastasis was found in 5 cases. Postoperative immunohistochemistry showed that MUC-1 was negative in all patients. MUC-2,PCNA and Ki-67 were positive in all patients. All 9 cases that were followed-up died within 5 -22 months,with an average survival time of 10 months. Conclusions The diagnosis of MNAC depends on pathology. Its prognosis is poor.

BACKGROUND:Extensive studies have shown that transcutaneous electrical nerve stimulation (TENS) plays a positive role in relieving the pain caused by a variety of diseases. However, its exact effect to manage pain in patients with knee osteoarthritis is stil controversial. TENS is classified into h-TENS and l-TENS, but currently its respective role in relieving the pain caused by knee osteoarthritis is not clear yet. OBJECTIVE: To compare the efficacy of h-TENS and l-TENS on pain relieving among patients with knee osteoarthritis. METHODS: A computer-based search was performed on PubMed, Embase and Cochrane database for randomized controled trials on TENS for the treatment of knee pain in patients with knee osteoarthritis which were reported before February 2014. Methodology quality of the trials was criticaly assessed and relative data were extracted. These studies were selected independently by two reviewers according to the inclusion and exclusion criteria. Meta-analysis was performed using Revman5.2 software. RESULTS AND CONCLUSION:A total of 10 randomized controled trials involving 519 cases were included. The results of meta-analysis showed that the h-TENS group had significant effects on pain relief in knee osteoarthritis patients in comparison to the control group [MD=-0.56, 95%CI(-0.98,-0.15),P=0.008]; the l-TENS group had no significant effect on pain relief in knee osteoarthritis patients in comparison to the control group [MD=-0.13, 95%CI(-1.63, 1.38),P=0.87]; the h-TENS group had significant effect on pain relief in knee osteoarthritis patients in comparison to the l-TENS group [MD=-0.85, 95%CI(-1.32, -0.37), P=0.000 5]. These findings indicate that h-TENS performs something positive to reduce pain in knee osteoarthritis patients that l-TENS cannot do. Owing to the limitations of this study, further work is needed to determine the role of TENS in pain management among patients with knee osteoarthritis.