BACKGROUND: Pathogenesis and pathophysiological changes of chronic compressive cervical myelopathy havenotbeen completely clarified.OBJECTIVE: To establish an animal model of experimental chronic compressive cervical myelopathy for the exploration of the pathological and electrophysiological changes after chronic spinal compression.DESIGN: A randomized and controlled observatory study using experimental animals as subjects.SETTING: An Animal Experimental Center of a University and an Orthopaedic Laboratory of Affiliated Hospital of a Military Medical University MATERIALS: The study was conducted in the Animal Experimental Center of Nantong Medical University and the Orthopaedic Laboratory of Shanghai Changzheng Hospital from June 2002 to April 2003. Sixty 12-week healthy Chinese rabbits of either gender with a bodymass between 2.5 kg and 3.0 kg were randomly divided into control group( n = 6) and study group( n = 54).METHODS: Titanic metal screw was put into C5 vertebra through cervical anterior approach for progressive compression to establish chronic cervical myelopathy model.MAIN OUTCOME MEASURES:Principal consequences: ①histological examination ;②electrophysiological examination. Secondary consequence:neural function evaluation.RESULTS: Totally 48 rabbits entered into result analysis, in which 6 rabbits from control group and 42 rabbits from study group. Modified Tarlov's motor function evaluation was 3 in 31 rabbits with compression signs, and 4 in 11rabbits without compression signs. The latency of N1 wave in cortical somatosensory evoked potentials (CSEP) was (9.11 ± 1.61 ), ( 11.36 ± 2.17)and (17.55 ± 3.73) ms respectively in animals of control group, animals of study group without compression signs and animals of study group with compression signs. The lantency of CSEP N1 wave was significantly longer in animals of study group with compression signs than that of the animals in the control group and study group without compression signs (P＜0.05).CONCLUSION: This animal model can simulate clinical invasion process of chronic compressive cervical myelopathy. The severer the spinal compression is, the more often the compression signs appear, the longer the lantency of CSEP N1 wave is, and the more serious the spinal pathological damages are.

AIM: To investigate the signaling mechanisms involved in the priming effects of lipopolysaccharide(LPS) on heat killed Staphylococcus aureus(HKSa)-induced nitric oxide(NO) production in macrophages.METHODS: Murine macrophage RAW264.7 was used in the experiment.Griess reagent was used to measure the content of nitrite in culture medium.Real-time PCR and Western blot was utilized to examine the mRNA and protein levels of toll-like receptor 2(TLR2),respectively.Dual luciferase reporter assay was used to assess the transcriptional activity of nuclear factor of activated T cells(NF-AT).RESULTS: The RAW264.7 cells pretreated with LPS for 24 h significantly enhanced NO production induced by HKSa,suggesting that LPS primed the macrophages and increased the reactivity of the cells to HKSa.LPS increased the mRNA and protein levels of TLR2 in a dose-dependent manner in RAW264.7 cells.The RAW264.7 cells pretreated with LPS enhanced NO production induced by peptidoglycan,one of the specific ligand of TLR2.The priming effect of LPS on HKSa-induced NO production was partly blocked by TLR2 neutralizing antibody.LPS significantly enhanced the transcriptional activity of NF-AT,which was inhibited by BAPTA/AM(a cell-permeable cytosolic calcium chelator) and cyclosporine A(CsA,an inhibitor for calcineurin).Both BAPTA/AM and CsA inhibited the priming effect of LPS on HKSa-induced NO production in RAW264.7 cells.CONCLUSION: The present study confirms the priming effect of LPS on the reactivity of RAW264.7 cells to HKSa.Pattern recognition receptor TLR2 and calcium/calcineurin/NF-AT signaling pathway may be involved in the priming process initiated by LPS.

Aim To study the effect of Baoxinbao film on endothelin(ET) and nitric oxide(NO) secretion in patients with stable angina pectoris(SAP).Methods 76 patients with SAP were randomly divided into two groups, with 40 cases in the baoxinbao group plastered with baoxinbao film and 36 cases in the isosorbide dinitrate group receiving isosorbide dinitrate. The levels of plasma ET and NO before and after treatment were observed. Results The concentrations of plasma ET were increased and plasma NO reduced significantly in the SAP patients respectively, as compared with those in the control group(all P

Objective To observe the changes of the peripheral blood T lymphocyte subsets following acute spinal cord injury and investigate the possible mechanism of these changes. Methods The SCI models of rats were made by Allen's method. Forty SD rats were divided into four groups, ie,normal control group, sham operation group, 100 g·cm group and 200 g·cm group. The expressions of CD4 and CD8 subsets of the peripheral blood T lymphocyte of the injured rats were determined by immunofluorescence labelling and flow cytometry at different times after injury. Results It was found that the expression of CD4 was significantly reduced to (30.40±4.76)% in 100 g·cm group and to (26.54± 9.34) % in 200 g·cm group, which were significantly lower than that of normal control group ( P ＜0.01 ). At 36 hours after injury, the ratio of CD4/CD8 was significantly reduced to 1.81 ± 0.55 in 100 g·cm group and and 1.29 ± 0.50 in 200 g·cm group, with statistical difference (P ＜ 0.05).Conclusions The immunoreaction is significantly depressed at the early stage of acute spinal cord injury. The severer injury results in more significant decrease of CD4 and ratio of CD4/CD8. The changes of CD4 and CD4/CD8 ratio can be used to indicate the severity of spinal cord injury.

Animals ; Disease Models, Animal ; Hypoglycemia ; chemically induced ; metabolism ; Hypothalamus ; drug effects ; metabolism ; Insulin ; pharmacology ; Intracellular Signaling Peptides and Proteins ; metabolism ; Male ; Neuropeptides ; metabolism ; Orexins ; Rats ; Rats, Sprague-Dawley

Mink plasmacytosis, caused by Aleutian Mink Disease Virus (AMDV), poses a threat to the development of the animal fur industry. Neutralizing antibodies against AMDV may result in a persistent infection rather than providing protection for minks. To date,no specific methods to prevent or cure this disease have been developed. In order to eliminate mink plasmacytosis, antibody detection technology has been used globally as a dominant approach to screen for AMDV-positive minks. This paper introduces the classical technology, counterimmunoelectrophoresis and emerging technology in terms of AMDV antibody detection,and provides a glimpse into the future development of these technologies.
Aleutian Mink Disease ; diagnosis ; immunology ; virology ; Aleutian Mink Disease Virus ; immunology ; isolation & purification ; Animals ; Antibodies, Viral ; immunology ; Immunoassay ; instrumentation ; methods ; Mink

Objective:To evaluate the effects of periodontitis on the expression of apoptosis-related proteins in pancreas of rats with Type 2 Diabetes Mellitus.Methods:Spontaneously type 2 diabetic OLETF rats were randomly divided into 2 groups:diabetes with or without periodontitis(diabetes group and combination group).LETO rats with the same germline and the same age but having normal glucose tolerance were randomly divided into control group and periodontitis group.20 weeks after periodontitis were established,all the rats were sacrificed and the pancreas were pathologically examined by HE staining.The expression of Bax,Bcl-2 and Caspase-3 in the pancreas islet were detected by immunohistochemistry staining and semi-quantitative analysis.Results:The expression of Bax, Bcl-2 and Caspase-3 in the pancreas islet was no significant difference between control and periodontitis groups(P=0.324,P=0.091,P=0.852).Compared with diabetes group,the expression of Bax and Caspase-3 in combination group showed a significant increase(P=0.000,P=0.000),and the expression of Bcl-2 was significantly decreased(P=0.022).Conclusion:Under healthy conditions,periodontitis has no effect on the expression of apoptosis-related proteins in rat pancreas islet.However,in rats with diabe-tes,periodontitis may affect the expression of apoptosis-related proteins in pancreas islet.

Objective To explore the relation between the expression of PBMCs IP-10 mRNA and systemic lupus erythematosus.Methods The expression of PBMCs IP-10 mRNA was investigated by RT-PCR semi quantitative method and samples from 46 patients with SLE,20 patients with RA,11 non-SLE patients with renal impairment and 20 healthy volunteers.Results The expression of PBMCs IP-10 mRNA in active SLE group was significantly higher than that in inactive group(P0.05).Serum levels of IP-10 were highly correlated with the expression levels of PBMCs IP-10 mRNA(r=0.897 1,P

Objective To investigate the effects of melatonin on choline acetyltransferase (ChAT) in rat hippocampus after isoflurane anesthesia. Methods Sixty male SD rats weighing 390 - 440 g were randomized into 5 groups (n = 12 each): control group (group C), 1% isoflurane group (group Ⅰ), 1% isoflurane + melatonin group (group IM) , 2% isoflurane group (group J) and 2% isoflurane + melatonin group (group JM) . In IM and JM groups, melatonin 10 mg/kg was administered intraperitoneally once a day for 7 consecutive days, while equal volume of normal saline was given intraperitoneally instead of melatonin in C, I and J groups. Groups Ⅰ and IM inhaled 1% isoflurane and groups J and JM 2% isoflurane for 4 h on 7th day. All the rats underwent Morris water maze test on the day after anesthesia for assessment of learning and memory ability (escape latency and probe time) . The training test was performed 4 times a day for S days. Six rats randomly selected from each group were sacrificed the end of the test. The blood samples were collected for detection of plasma melatonin level by ELISA.The brain tissues were removed for determination of the expression and activity of ChAT in hippocampus by Western blot or colorimetric assay. The left rats were selected and sacrificed for determination of the number of ChAT positive neurons in hippocampal CA1 region and entate gyrus by immunofluorescence. Results The plasma melatonin level and expression and activity of ChAT were significantly lower in group I than in group C ( P ＜ 0.01) . The escape latency was significantly longer, the probe time was significantly shorter, and the plasma melatonin level and expression and activity of ChAT were significantly lower in group J than in group C ( P ＜ 0.05 or 0.01) . The escape latency was significantly shorter, the probe time was significantly longer, and the plasma melatonin level and expression and activity of ChAT were significantly higher in group IM than in group Ⅰ ( P ＜ 0.05 or 0.01). The escape latency was significantly shorter and the plasma melatonin level and ChAT activity were significantly higher in group JM than in group J ( P ＜ 0.05 or 0.01) . The results of immunofluorescent staining showed that the number of ChAT positive neurons in hippocampal CA1 region and dentate gyrus wag consistent with the changes in the measured ChAT expression. Conclusion Melatonin can reduce isoflurane-mediated inhibition of ChAT expression and activity and thus improve spatial memory impaired by isoflurane anesthesia in rats.

Objective To study associations between manganese superoxide dismutase 9 Ala/Val (Mn-SOD 9 Ala/Val)genet-ic polymorphism and total superoxide dismutase (T-SOD)and Mn-SOD activity and the impact on coronary heart disease (CHD)were studied.Methods There were 82 CHD patients and 57 controls in this research.Sequencer was used to identify the genotype of Mn-SOD 9 Ala/Val genetic polymorphism and colorimeter was used to detect the serum T-SOD and Mn-SOD activity.Results Compared with the control group,the serum T-SOD and Mn-SOD activity of the CHD group was significantly reduced(t=4.83,6.57,P all<0.05),while the VV genotype and V allele of Mn-SOD 9 Ala/Val genetic poly-morphism of the CHD group were higher (χ2 =4.75,P <0.05).The serum T-SOD and Mn-SOD activity of the Mn-SOD 9 VV genotype was significantly lower than the Mn-SOD 9 AA genotype(t=2.96,3.11,P all<0.05).Conclusion The ser-um T-SOD and Mn-SOD activity in the CHD patients was reduced.Mn-SOD 9 Ala/Val genetic polymorphism was involved in the pathogenesis of CHD by influencing the Mn-SOD activity.