For a long period of time, silk fibroin has been applied in biomedical areas. Along with the development of biotechnology, new functions of silk fibroin are being found and developed. From the suture of surgery to the therapeutic drug and the ordinary tissue engineering frame to high grade frame with drug buffer system, exploitation of silk fibroin is constantly introduced with something new from the old ones. In our review, we summarize the applications of silk fibroin in tissue engineering, drug buffer system and medical care.
Fibroins ; therapeutic use ; Humans ; Tissue Engineering

The cultured HUVE cells were infected with HFRS veruses. At different intervals after in-fection cytotoxicity of NK and LAK by 4 hours Cr release method. It was found that the infec-tion of endothelial cells inhibit the lytic activity of NK and LAK cells. Theinhibition. It is sug-gested that the deceased susceptibility of HFRS virus infected endothelial cells to NK and LAKcells may protect the viruses from the cellular immunity during the course of HFRS.

Evolutionary psychology holds such an opinion that negative situation may threaten survival, trigger avoidance motive and have poor effects on the human-body function and the psychological quality. Both disgusted and sad situations can induce negative emotions. However, differences between the two situations on attention capture and emotion cognition during the emotion induction are still not well known. Typical disgusted and sad situation images were used in the present study to induce two negative emotions, and 15 young students (7 males and 8 females, aged 27 ± 3) were recruited in the experiments. Electroencephalogram of 32 leads was recorded when the subjects were viewing situation images, and event-related potentials (ERP) of all leads were obtained for future analysis. Paired sample t tests were carried out on two ERP signals separately induced by disgusted and sad situation images to get time quantum with significant statistical differences between the two ERP signals. Root-mean-square deviations of two ERP signals during each time quantum were calculated and the brain topographic map based on root-mean-square deviations was drawn to display differences of two ERP signals in spatial. Results showed that differences of ERP signals induced by disgusted and sad situation images were mainly manifested in T1 (120-450 ms) early and T2 (800-1,000 ms) later. During the period of T1, the occipital lobe reflecting attention capture was activated by both disgusted and sad situation images, but the prefrontal cortex reflecting emotion sense was activated only by disgusted situation images. During the period of T2, the prefrontal cortex was activated by both disgusted and sad situation images. However, the parietal lobe was activated only by disgusted situation images, which showed stronger emotional perception. The research results would have enlightenment to deepen understanding of negative emotion and to exploredeep cognitive neuroscience mechanisms of negative emotion induction.
Adult ; Attention ; Brain Mapping ; Cognition ; Electroencephalography ; Emotions ; Evoked Potentials ; Female ; Humans ; Male ; Occipital Lobe ; physiology ; Parietal Lobe ; physiology ; Prefrontal Cortex ; physiology

Objective:To investigate the neuropsychological characteristics of Chinese agraphia caused by basal ganglia(BG)infarction.Methods:The writing abilities of 40 patients with BG infarction were detected by Chinese agraphia battery(CAB),and all the writing scores and agraphia quotient were calculated.The head CT/MRI images in agraphia and non-agraphia groups were standardized,the infarction were revealed and the superposition of two-dimensional arrays were performed,so that the central tendency of infarction was visually displayed.Results: Among the 40 patients,21 had left BG infraction,and 17 had agraphia;19 had right BG infraction,and 4 had agraphia.The two-dimensional superimposing neuroimages showed that BG infarctions caused agraphia was mostly in the left BG,including the left putamen,the head and body of the caudate nucleus,but there were fewer infarctions in the right putamen and the body of the candate nucleus.BG infarction caused agraphia was mostly aphasic agraphia,which was characterized by the orthographic disorders,paragraphia,and grammar mistakes.Conclusions: BG infarction may result in aphasic agraphia,which suggested that BG is involed in writing and processing,and it is the subcortical center of this advanced neurofunction in writing.

Objective: To evaluate the effects of micro-arc oxidation (MAO) and poly-L-lactic acid (PLLA) surface-modification on the biocompatibility of magnesium alloy WE42. Methods: Micro-arc oxidation surface-modificated WE42 (MAO/WE42) materials and MAO+PLLA surface-modificated WE42(MAO+PLLA/WE42) materials were prepared. The surface topography of materials in the physiological environment was observed in vitro by scanning electron microscopy. The human umbilical vein endothelial cells(HUVECs) were treated by leaching liquor of materials. The relative growth rate(RGR) was assessed by MTT assay to evaluate the level of cytotoxicity. The coagulation time(PT, RT) and hemolytic ratio were determined to evaluate the blood compatibility of those materials. Results: The observation of scanning electron microscopy indicated that WE42 corroded seriously after immersion. There were no obvious corrosion holes on the surface of MAO/WE42 and MAO+PLLA/WE42 materials after immersion. It was found that there were good anticoagulant properties but no apparent cytotoxicity in MAO/WE42 and MAO+PLLA/WE42 materials. The results of hemolysis test showed that there were lower hemolysis rates in MAO and MAO+PLLA materials than that of WE42. The material of MAO+PLLA possessed the better anti-hemolytic properties than that of MAO(P < 0.01). Conclusion: Micro-arc oxidation surface modification improved the biocompatibility of WE42. PLLA sealing treatment improved the anti-hemolytic performance of WE42. MAO+PLLA provided a safe drug-loading surface for drug-eluting stents of magnesium alloy.

AIMTo further elucidate the role of agmatine on the pharmacological effects of opioids. METHODSThe effect of L-arginine and L-arginine decarboxylase(L-ADC) antibodies on pain threshold, morphine ntinociception and tolerance were investigated in mouse acetic acid writhing test, mouse radiant heat tail flick test and mouse hot plate test. RESULTSIn mouse acetic acid writhing test, intracerebroventricular injection of L-arginine dose-ependently inhibited the writhing of mice compared with saline control. L-arginine did not influence the tail flick latency itself in mouse radiant heat tail flick test, but enhanced antinociceptive effect of morphine in a dose-dependent manner. The possible maximal analgesia percentage of morphine 2.5 mg*kg-1 was increased from 23% to 71%. Furthermore, L-arginine inhibited acute tolerance induced by morphine 100 mg*kg-1in mouse radiant heat tail flick test. The effect of L-arginine as mentioned above could be antagonized by idazoxan (3 mg*kg-1, ip), which is a selective antagonist of imidazoline receptors. L-ADC specific antibodies inhibited morphine antinociception and promoted the development of tolerance to morphine in mouse radiant heat tail flick test and 55℃ hot plate test. CONCLUSIONL-Arginine and L-ADC play important roles in the formation of pain threshold, morphine antinociception and tolerance.

BAcKGROUND:In recent years,the pedicle screws fixation technique,which is used in fixation for atlantoaxial instability associated with trauma,severe degeneration and tumorectomy,has been developed.However,this kind of technique easily causes several complications,including malpositional screws,vascular injuries,and even vertebral artery injury.Based on the biomechanical characteristics of memory alloy and determination of atlantoaxial data,a neotype shape memory alloy cervical hook was designed to treat atlantoaxial instability.OBJECTIVE:To investigate the biomechanieal characteristics of the neotype shape memory alloy cervical hook for atlantoaxial instability.DESIGN,TIME AND SETTING:Repeated measurement analysis of variance test was performed in the Laboratory of Clinical Anatomy and Medical Biomechanics,Southern Medical University between March and April 2008.MATERIALS:Eight fresh adult craniocervical specimens(C0-C4)were provided by Department of Clinical Anatomy,Southern Medical University.Atlantoaxial neotype shape memory alloy cervical hook(50.8%-51.8%nickel and the remaining part was titanium)was fabricated by Shanghai Xinchang Memory Alloy Co.,Ltd.METHODS:The included eight C0-C4 specimens were used to test three-dimension ranges of motion(ROM)by fixation and neotype shape memory alloy cervical hook fixation.Then,the positions of spine varying from no loading to the maximum loading status were scanned and analyzed using image processing software to determine the three-dimensional ROM under different statuses.MAIN OUTCOME MEASURES:Three-dimensional ROM of tested specimens.RESULTS:Neotype shape memory alloy cervical hook fixation and Germany AESCULAP SSE hanger fixation had similar flexion-extension range of motion(P=0.595).Lateral bending three-dimensional ROM was greater in the neotype shape memory alloy cervical hook fixation group than in the Germany AESCULAP AAE hanger fixation(P< 0.05).The rotatory three-dimensional ROM was smaller in the neotype shape memory alloy cervical hook fixation group than in the Germany AESCULAP AAE hanger fixation(P<0.05).CONCLUSION:Neotype shape memory alloy cervical hook fixation had comparative post-surgery immediate stability with the Germany AESCULAP AAE hanger fixation.Neotype shape memory alloy cervical hook fixation produced a little worse biomechanical lateral bending stability and a little better biomechanical rotatory stability than Germany AESCULAP AAE hanger fixation.

By Silica gel, Sephadex LH-20 and other materials for isolation and purification and by physicochemical methods and spectral analysis for structural identification, 23 compounds were isolated and identified from ethyl acetate portion of alcohol extract solution of Osmanthus fragrans fruits. Their structures were identified as nicotinamide (1), D-allitol (2), 5-hydroxymethyl-2-furancarboxaldehyde (3), acetyloleanolic acid (4), benzoic acid (5), ergosta-7,22-dien-3-one (6), beta-sitosterol (7), borreriagenin (8), cerevistero (9), c-veratroylglycol (10), methyl-2-O-beta-glucopyranosylbenzoate (11), 3', 7-dihydroxy-4'-methoxyisoflavon (12), umbelliferone (13), caffeic acid methyl ester (14), oleanolic acid (15), (-) -chicanine (16), dillapiol (17), 3beta,5alpha, 9alpha-trihydroxyergosta-7-22-dien-6-one (18), 2alpha-hydroxy-oleanolic acid (19), betulinic acid (20), betulin (21), 3, 3'-bisdemethylpinoresinol (22), and lupeol (23). All compounds were isolated from the osmanthus fruit for the first time. Except for compounds 4, 7, 15, 19, 23, the rest ones were isolated from the this plant for the first time.
Drugs, Chinese Herbal ; chemistry ; Fruit ; chemistry ; Oleaceae ; chemistry

OBJECTIVE:To investigate whether the magnesium sulfate injection(MSI)into cisterna magna in a rabbit with subarachnoid hemorrhage(SAH)can reverse the cerebral vasospasm and damage of brain tissues.METHODS:The single-hemorrhage SAH rabbit model was used.Thirty New Zealand white rabbits were randomly divided into the following three groups(n=10,in the each group):sham group,model group and MSI group.At 24 hours after SAH,the rabbits were injected with 0.1 mL?kg-1 of saline into cisterna magna in sham and model groups,while 0.1 mL?kg-1 of 4% magnesium sulfate was injected into cisterna magna of rabbits in MSI group.All animals were sacrificed at 48 hours after SAH.Basilar arteries and hippocampus were then removed for measurement of the cross-sectional areas of basilar arteries and the hippocampus normal neuron density of CA1 regions.RESULTS:The cross-sectional areas of basilar artery and the hippocampus normal neuron density of CA1 regions were smaller in model group than in the other two groups(P0.05).CONCLUSIONS:This study results indicate that injecting magnesium sulfate into cisterna magna can reverse the cerebral vasospasm and the following hippocampal neuron damage in rabbits with subarachnoid hemorrhage.

Objective To evaluate the effects of isoflurane anesthesia on NR1 expression and neuronal apoptosis in the hippocampus and cortex of adult rats .Methods Thirty-six adult male Sprague-Dawley rats , weighing 250-280 g ,were randomly assigned into 3 groups using a random number table :control group (group C , n=6 ) ,O2 inhalation group (group O , n=6 ) and isoflurane anesthesia group (group I , n=24 ) .The rats were exposed to 2% isoflurane (group I) ,to pure oxygen (group O) ,or to air (group C) for 2 h .At 2 h ,and 1 ,7 and 14 days after the rats were awake (T1-4 ) ,Morris water maze test was performed .The rats were then sacrificed and brains were removed for isolation of the hippocampus and cortex .NR1 expression was detected using SABC immuno-histochemical technique and neuronal apoptosis was determined using TUNEL .Results Compared with group C , the escape latency at T2 and total swimming distance at T1 ,2 were significantly prolonged , and the expression of NR1 in hippocampi was down-regulated at T1 ,2 in group I ,and the expression of NR1 in the cortex was down-regulated in O and I groups ( P<0.05) .There was no significant difference in the apoptosis index between the three groups ( P> 0.05 ) .Conclusion Isoflurane anesthesia can decrease the cognitive function transiently ,which is related to inhibition of up-regulation of NR1 expression in the hippocampi ,but not related to neuronal apoptosis in adult rats .