Objective To review the examination techniques and the current research progress of the magnetic resonance diffusion weighted-imaging (DWI) used in liver. Methods The recent and relevant literatures about the principles and the current study situation of liver DWI were scrutinized and analyzed retrospectively. In addition, the existing problems of liver DWI were discussed. Results DWI could demonstrate the normal and abnormal structure and function through measuring the diffusion motions of water molecule in the liver. With the improving technology and better understanding of diffusion dynamics, DWI has been used for the diagnosis and differential diagnosis for hepatic diseases. Conclusion DWI as a non-invasive examine method, may provide valuable functional information for clinical diagnosis and treatment.

Adult ; Dust ; Female ; Glass ; Humans ; Male ; Middle Aged ; Occupational Diseases ; epidemiology ; Prevalence ; Skin Diseases ; epidemiology ; Young Adult

OBJECTIVE:To investigate the risk,advantages and disadvantages and countermeasures of new drugs,generic drugs and imported drugs in different transfer opportunities,and to provide basis for improvement of development strategy for phar-maceutical enterprises. METHODS:The analysis was done in accordance with relevant regulations on transferable projects in the process of applying for registrations of new drugs,generic drugs and imported drugs. The transfer period and risk were explored and countermeasures were put forward. RESULTS & CONCLUSIONS:Transferable projects included intellectual property rights (patents,patent application,technical secrets,application information,non-disclosed data,etc.)and ownership rights(clinical tri-al approvals,new drug certificates,drug approval number,pharmaceutical product registration certificates,imported product regis-tration certificates,etc.)in the process of applying for registrations. There are 4 opportunities for drug technology transfer,opportu-nity 1 is before applying clinical trial approvals after the completion of non-clinical research such as pharmacology,toxicology;op-portunity 2 is ahead of clinical trial after the acquirement of clinical trial approvals;opportunity 3 is new drug technology transfer;opportunity 4 is production technology transfer. The new drugs have 4 transfer opportunities,generic drugs and imported drugs can transfer in opportunity 1,2,4. Different transfer opportunities present different risks and profits. The risk gradually decreases with the further promotion of drug registration process,while the innovation decreases at the same time. Pharmaceutical enterprises should combine with the policy,market and their own features to select a suitable transfer period.

BACKGROUND:Col agen and silk fibroin materials for construction of spinal cord scaffolds have been proven to repair or partial y repair damaged spinal cord nerve function. OBJECTIVE:To introduce partial characteristics of the col agen and silk fibroin and to review the recent progress and application as scaffolds in spinal cord tissue engineering. METHODS:A computer-based search of CNKI and PubMed databases (2003-01/2012-10) was performed for articles addressing the application of col agen and silk fibroin scaffolds in spinal cord injury with the keywords of“col agen, silk fibroin, scaffold, spinal cord injury”in Chinese and English, respectively. RESULTS AND CONCLUSION:Col agen has low antigenicity, good biocompatibility and biodegradability. Col agen and its degradation products can cause no inflammatory reactions in the body, but have the disadvantages of rapid degradation and poor mechanical properties. Silk fibroin has good biocompatibility and excellent mechanical properties, but its degradation is slow. The col agen and silk fibroin are compounded using an electrostatic spinning technology to improve the physical properties of the material on the basis of maintaining good biocompatibility. At present, fibroin or col agen materials in terms of nervous system repair have been studied, laying some foundation for spinal cord tissue engineering. Considering the similar characteristics and mechanics performance to the spinal cord tissue, col agen/silk fibroin composite materials are expected to become the ideal scaffold materials for spinal cord tissue engineering.

Objective To explore the effect of electromyogram-triggered neuromusclar stimulation (ETNS) on motor function of upper limbs of stroke patients. Methods 45 stroke patients from July, 2011 to December, 2012 in China Rehabilitation Research Center were randomly divided into control group (n=15), neuromuscular electrical stimulation (NMES) group (n=15) and ETNS group (n=15). 3 groups were given routine medication and rehabilitation treatment. They were assessed with the largest surface electromyography (sEMG), Simple Test for Evaluating Hand Function (STEF), and modified Barthel Index before and after treatment. Results After treatment, the range of sEMG of extension carpi radialis and STEF improved in three groups (P<0.05). NMES group and ETNS group were better than the control group (P<0.05), and ETNS group was better than NMES group (P<0.05). The scores of modified Barthel Index rose (P<0.05), NMES group and ETNS group were better than the control group (P<0.05). Conclusion Both NMES and ETNS can improve the motor recovery of upper limbs after stroke, and ETNS is more effective.

Iron uptake mechanism of Vibrio alginolyticus was primarily investigated. V.alginolyticus could survive in the medium with high-concentration iron chelator. The strain of V. alginolyticus isolated from diseased fish produced more siderophore than that from marine environment. The extract of siderophore from V. alginolyticus could stimulate the growth of Escherichia coli mutant AN93. Under iron limitation,the growth rate was decreased and several outer membrane proteins were induced. Adding iron into the iron-limited medium the normal growth could be recovered.

Objective: To investigate analgesic effect of gabapentin(GBP)combined with agmatine(AGM)on diabetic neuropathic pain(DNP)model rats and explore possible mechanism. Methods: SPF SD male rats were injected intraperitoneally with STZ 65 mg/kg to create a neuropathic pain model of diabetic rats. The model rats were randomly divided into 5 groups(n=8): the model group, low-dose GBP group(30 mg/kg, ip), high-dose GBP group(100 mg/kg, ip), AGM group(80 mg/kg, ig)and the GBP-AGM combined group(GBP 30 mg/kg, ip+AGM 80 mg/kg, ig). In addition, a control group was set with 8 randomly selected normal rats. The control group and the model group were intragastrically and intraperitoneally administered an equal volume of physiological saline, respectively, while the test groups were administered drugs with the given dose in the indicated manner, all for continuous 14 days. The rat body mass, tail vein blood glucose, mechanical withdrawal threshold(MWT)and thermal withdrawal latency(TWL) were measured on day 1 before STZ injection and every 7th day after STZ injection, and the plantar tenderness meter was used for the MWT and TWL measurement. The rats were sacrificed 24 h after the last administration, and the spinal cord tissues were harvested. Western blotting was used to detect the expression of p-ERK and c-Fos protein in spinal cord tissues. Results: Compared with the normal control group, the body mass was reduced, blood glucose increased, MWT decreased, and TWL shortened in the model group, all significantly(P<0.01). After 14 days of the continuous drug administration, compared with the model group, the body mass and blood glucose showed no significant changes(both P>0.05)in all of the drug-test groups, while the MWT was increased and the TWL was prolonged in the GBP 100 mg/kg group and the GBP-AGM combined group(both P<0.01). Western blotting results showed that the level of p-ERK and c-Fos protein in the spindal cord was significantly higher in the model group than in the control group(P<0.05). Further, the p-ERK and c-Fos protein level was significantly lower in the GBP+AGM combined group than in the model group(P<0.05)and there was no statistical difference between the GBP 100 mg/kg group and the GBP-AGM combination group. Conclusion: The combination of GBP 30 mg/kg with AGM 80 mg/kg could alleviate neuropathic pain in diabetic rats, which is similar to GBP 100mg/kg and the analgesic effect is likely related to the inhibition of ERK/c-Fos signaling pathway in the spina cord.

This review introduced the research progress of covalent modification strategies in local anesthetic drug delivery systems. As a commonly used and multimodal analgesic drug, local anesthetics have limited duration of action and potential toxicity in clinical application. In order to prolong the analgesic effect and reduce systemic toxicity, researchers are committed to the development of sustained-release local anesthetics with long-lasting dose-controlled-release functions. When it comes to the delivery of local anesthetics, the covalent modification strategy is a key approach. By covalently binding drugs to large molecule carriers, covalent modification strategies can improve drug stability, targeting and delivery efficiency. Macromolecular prodrugs can modulate the kinetic process of the drug, so that the drug is released in the form of the active ingredient and achieve better therapeutic effects. In recent years, stimulus-responsive macromolecular prodrugs have become a research hotpot for local anesthetic drug delivery systems, and the stimulus-responsive performance of macromolecular prodrugs can rapidly release drugs under internal and external stimulus conditions, and maintain low toxicity and high efficiency in blood circulation and normal tissues. These emerging research directions provide important guidance for prolonging the analgesic effect of local anesthetics and reducing systemic toxicity, and provide new idea for the development of more effective drug delivery systems in the future.

BACKGROUND: Thrombus formation and neointimal hyperplasia limit its use for revascularization of small-caliber vessels (<6mm diameter) in the coronary or peripheral circulation.OBJECTIVE: To improve hemocompatibility, the luminal surface of a small diameter expanded polytetrafluoroethylene (Eptfe) vascular prosthesis was modified with alginate and recombinant hirudin.DESIGN: Observational experiment.SETTING: This study was performed in Nanomedicine and Biosensor Laboratory, Bio-X Center, Harbin Institute of Technology from Marcy 2006 to June 2007.MATERIALS: The GORE-TEX Epife vascular grafts (W. L Gore & Associates, Inc., Flagstaff, AZ) used in this study were 4mm in internal diameter. rHir was obtained from Calbiochem, Germany. Sodium alginate (also called alginic acid sodium salt; medium viscosity) was purchased from Sigma.METHODS: A p-diazonium diphenyl amine polymer (PA) was used as an interlayer between alginate and recombinant hirudin (rHir). The diazonium moieties were capable of covalently coupling with electron-rich aromatic systems such as histidine and tyrosine residues of hirudin. No need for chemical pretreatment took all advantage by preserving the bulk properties with almost no effect on stability and elasticity of the Eptfe vascular graft. rHir amount on Epife surface Was determined by the Micro BCA (Bicinchoninic acid) Protein Assay kit.MAIN OUTCOME MEASURES: ① Determination rHir amount on Eptfe surface; ② Static water contact angles; ③ Attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR) was employed to confirm the change taking place in the Eptfe graft surface modification process; ④ Characterization of the surface morphology and platelet adhesion by SEM; ⑤ APTT and PT; ⑥ Percent hemolysis.RESULTS: ① The amount of rHir adsorbed onto the Eptfe vascular was deduced to be 16.35 μg/cm2. ② Surface analysis ATR-FTTR revealed the presence of new functional groups on the modified graft surfaces. ③ The water contact angle of the modified graft surface decreased. ④ The longer APTT and PT value lower than 5% hemolysis level and dramatically decrease of platelet adhesion assay showed that rHir modified graft had great improved blood compatibility.CONCLUS10N: Cross-linked Alg/rHir onto Eptfe can improve luminal surface and hemocompatibility.

SHIV-CN97001 played an important role in assessing the immune effect and strategy of the AIDS vaccine which included genes of the predominant prevalent HIV-1 strain in China. In this study, SHIV-CN97001 was in vivo passaged serially to construct pathogenic SHIV-CN97001/rhesus macaques model. To identify variation in the gp120 region of SHIV-CN97001 during passage, the fragments of gp120 gene were amplified by RT-PCR from the plasma of SHIV-CN97001 infected animals at the peak viral load time point and the gene distances (divergence, diversity) were calculated using DISTANCE. The analysis revealed that the genetic distances of SHIV-CN97001 in the third passage animals were the highest during in vivo passage. It had a relationship between viral divergence from the founder strain and viral replication ability. The nucleic acid sequence of the V3 region was highly conservative. All of the SHIV-CN97001 strains had V3 loop central motif (GPGQ) and were predicted to be using CCR5 co-receptor on the basis of the critical amino acids within V3 loop. These results show that there was no significant increase in the genetic distance during serial passage, and SHIV-CN97001 gp120 gene evolved toward ancestral states upon transmission to a new host. This could partly explain why there was no pathogenic viral strain obtained during in vivo passage.