Effect of dopamine on hemodynamics and cerebral oxygen metabolism in the early stage-of post-resuscitation in rabbit with cardiac arrest北大核心CSCD

Objective To observe the effects of dopamine in different doses on hemodynamics and cerebral oxygen metabolism in the early stage of post-resuscitation in rabbit with cardiac arrest. Methods Healthy adult rabbits were randomly(random number) divided into 4 groups according to the different doses of dopamine administration: control group (CG), low dose group (LG), medium dose group (MG), high dose group (HG), (n=15 in each group). Ventricular fibrillation (VF) was induced by electricity and cardiopulmonary resuscitation (CPR) was performed subsequently as the experiment designed. When 10 rabbits with restoration of spontaneous circulation (ROSC) were got each group, it was enough for experiment carried out. Cardiac output (CO), mean arterial pressure (MAP), heart rate (HR), systemic vascular resistance index (SVRI) and the cerebral local tissue blood oxygen saturation (TOI) were observed at 0 min, 15 min, 30 min, 60 min, 120 min after ROSC. The animals were sacrificed at 120 min after ROSC, brain tissues were harvested for study by using HE staining. Repeated measure analysis of variance was used to determine the statistical significance among the four groups at different intervals. Multi-group quantitative data was analyzed by one way ANOVA and then further by LSD test for multiple comparisons. Chi-square test or Fisher's exact probabilities was applied for multi-group binomial classification variable. Log-rank test was used for comparisons of survival curves in four groups. A two-tailed value of P<0.05 was considered statistically significant. Results There were no differences in the rate of ROSC among groups. Compared with CG and LG, ROSC time was shorter in MG (27715 vs. 19012, PO.01 ; 25216 vs. 19012, P=0.016 ) with higher 120 min survival rate ( 20% vs. 90%,∗2=9.899, P=0.005; 30% vj. 90%,∗2=7.5, P=0.02) . CO was higher in MG than that in other groups at all given intervals in the early stage of post-resuscitation(P<0.05). MAP levels were significantly higher in MG and HG compared with CG and LG at given intervals 15 min after ROSC (P相似文献   

家兔体内低密度脂蛋白受体分布的免疫荧光研究

以本实验室制备的两种抗兔低密度脂蛋白受体单克隆抗体，进行间接免疫荧光染色，观察此种受体在兔各种组织中的分布。结果显示，肝细胞、肾上腺皮质细胞的特异性免疫荧光最强；卵泡细胞、黄体细胞、肠道及支气管上皮细胞和表皮基底细胞等都显示较强的免疫荧光；心肌、骨骼肌、肾上腺髓质及结缔组织的荧光很弱，而脑实质几乎无荧光反应。提示低密度脂蛋白受体活性可能与组织的生理功能和代谢特性有关。     

Flow studies in a rigid model of an aorto-renal junction A case for high shear as a cause of the localization of sudanophilic lesions in rabbits

Flow studies were made in a rigid model of an aorto-renal junction in an attempt to explain two observations made in our laboratory in cholesterol-fed rabbits. First, the area of the lesion was proportional to the area of the orifice it surrounded, and hence probably to the flow into the branch. Second, lesions developed proximal as well as distal to blind stumps of a renal artery in nephrectomized rabbits. The branch had a sharp entrance, and came off at 90°. The area ratio of the branch and distal aorta to the proximal aorta was 1.27 and steady flow at Reynolds numbers of 570–1070 was studied both with dye injections and with a hot-film anaemometer. The flow ratio was varied from 0.16 to 0.58.

Secondary motions were observed in the main channel and in the side branch at all flow rates. Boundary layer separation occurred on the outer wall of the main branch and on the proximal wall of the side branch. The thickness of the boundary layer separation in the main branch depended on the flow rate ratio.

Downstream from the junction the velocity profiles were highly asymmetric in both the renal artery and the distal aorta. In the plane of the junction, peak velocities were skewed towards the inner wall. The velocity profiles perpendicular to the plane of the junction were less disturbed.

The calculated shear stress on the inner wall of the main branch within one diameter of the junction was much higher than that calculated for the corresponding Poiseuille flow. The magnitude of the shear stress, and its extension downstream from the junction increased as the flow into the branch increased. This correlated with previous observation by Cornhill and Roach [1] in the cholesterol-fed rabbit, that atherosclerotic lesions develip in regions of high shear

If the branch was occluded, no vortex formed in it, and streamlines in the trunk were not affected. This is opposite to the observations of Malcolm and Roach [2] in glass models with a rounded junctional zone where a vortex formed at the entrance when the branch was occluded. Since blind stumps develop proximal as well as distal lesions in the cholesterol-fed rabbit [3], the entrance geometry is probably very critical.     

Analysis of immune responses against H pylori in rabbits

AIM： To investigate the immunogenicity of H pylori proteins, to evaluate the production rate of anti H pylori IgG antibodies in relation to time and to demonstrate the fidelity of newly optimized in-house enzymelinked immunosorbent assay （ELISA） technique as an alternative for H pylori infection assay.
METHODS： In the present study, 100 μg of formalinfixed H pylori whole cell antigens was injected into an experimental animal （New Zealand white female rabbit） intramuscularly on d 0, 16, 27 and 35. The first two doses were injected with adjuvants. On d 0, a serum sample was collected from the rabbit before immunization and this pre-immunized serum was used as a negative control for the whole study. To evaluate the immunogenic responses of the injected antigen, serum samples were collected from the rabbit at regular intervals up to d 42. The sera were analyzed using inhouse ELISA and Western blot techniques.
RESULTS： The production of anti Hpylor/IgG antibodies in the rabbit in response to the injected antigen increased almost exponentially up to d 14 and after that it was maintained at the same level until the last day （d 42）. By analyzing the immune profiles of immunized sera, 11 proteins were identified to be immunogenic, among them 2 （approximately 100 kDa and 85 kDa） were most prominent.
CONCLUSION： Analysis of the immune responses against pathogenic microorganisms like H py/ori is necessary for the development of various diagnostic and preventive approaches. The results of this experiment reveal that the formalin-fixed H pylori whole cell antigens injected into the rabbit are highly immunogenic. These prominent proteins （approximately 100 kDa and 85 kDa） might have higher immunogenic effects among humans infected with H pylori and some of these immunogenic proteins can be included in diagnostic approaches based on serology and also for vaccine formulation. The in- house ELISA is a promising alternative compared to invasive techniques.     

介入治疗对兔VX2肝癌细胞增殖和凋亡的影响

目的研究介入治疗对肿瘤细胞凋亡和增殖的影响.方法建立兔VX2肝癌的动物模型,将实验动物分为介入组和对照组,用TUNEL法观察肿瘤细胞凋亡情况,采用原位杂交和免疫组化法检测凋亡和增殖相关基因bcl-2、bax及PCNA的表达情况.结果(1)介入组凋亡指数明显高于对照组,两组的细胞凋亡率分别为62.6 ±32.21%和21.4±10.43%(P＜0.05);介入组PCNA为38.80±15.73%,对照组为68.54±24.43%,前者显著低于后者(P＜0.05);(2)介入组bcl-2表达率为10.34±6.66%,显著低于对照组的24.5±11.53%(P＜0.05),而介入组bax的表达率为58.27±38.33%,显著高于对照组的32.13±23.76%(P＜0.05).bcl-2和bax基因mRNA表达与蛋白的表达相一致.结论抑制肿瘤细胞增殖和诱导其凋亡是介入治疗肝癌的重要机制之一.     

伴刀豆球蛋白A刺激高胆固醇血症兔的单核细胞释放高水平的生长因子

复制高胆固醇血症（ｈｙｐｅｒｃｈｏｌｅｓｔｅｒｏｌｅｍｉａ，ＨＣ）兔模型，取共血液分离单核细胞（ｍｏｎｏｃｙｔｅｓ ＭＣ），培养于含或不含伴刀豆球蛋白Ａ（ｃｏｎｃａｎａｖａｌｉｎ Ａ，ＣＯｎＡ）的无血清ＤＭＥ／Ｆ１２培养基中，惧要不同条件的ＭＣ条件培养基（ＭＣ－ｃｏｎｄｉｔｉｏｎｅｄ ｍｅｄｉｕｍ，ＭＣ－ＣＭ）并检测其促有丝分裂活性。结果表明经Ｃｏｎ Ａ激活的ＨＣ兔的ＭＣ－ＣＭ刺激＾３Ｈ－ＴｄＲ掺     

应用自制复合电极同步记录兔左心室游离壁三层心肌的单相动作电位

应用自制复合电极同步记录家兔在体三层心肌的单相动作电位 (MAP) ,并与经典的心内膜电极、心外膜吸附电极和三层独立电极记录结果进行比较。结果显示 :①应用自制复合电极同步记录家兔在体的三层心肌MAP形态及时程与经典的记录结果相近 ;②在心动周期 (CL)为 30 0ms时 ,三层心肌的MAP复极达 90 %的时程 (MAPD90 )无显著差异 ,当CL为 80 0ms时 ,家兔心外膜心肌 (Epi)、中层心肌 (M)和心内膜心肌 (Endo)的MAPD90 分别为 2 15± 18,2 6 2± 16 ,2 16± 12ms,M与Epi及Endo相比 ,差异有显著性 (P <0 .0 5 ,n =8) ,跨室壁复极离散度为 34± 3ms。结论 :应用复合电极同步记录在体心肌跨室壁三层MAP是可行的 ,家兔心脏跨室壁心肌电生理在正常心率时无明显差异 ,而当心率减慢时则异质性增加。     

Effect of polyglycolic acid sheets with fibrin glue (MCFP technique) on the healing of wounds after partial resection of the border of the tongue in rabbits: a preliminary study

The aim of this study was to examine the effectiveness of covering wounds to the tongue with a polyglycolic acid (PGA) sheet and fibrin glue. Eighteen mature male Japanese white rabbits had a unilateral glossectomy involving an area 10mm×10mm×2mm. After glossectomy the tongues were covered with PGA sheets 8mm×8mm in size and fibrin glue (mucosal defect covered with fibrin glue and polyglycolic acid sheet=MCFP) 1 week after the operation (n=3), after 2 weeks (n=3), and after 4 weeks (n=3). In control groups, after 1, 2, and 4 weeks (n=3 in each group), the partially resected tongues were closed with absorbable sutures (polyglactin 910). One week (experimental and control groups 1), 2 weeks (experimental and control groups 2) and 4 weeks (experimental and control groups 3) after operation the tongues were harvested and stained for microscopic examination. Histological examination showed that the covered wound surface had not epithelialised and the basal layer had yet to form in experimental group 1, but had formed in experimental group 2. However, in control group 1, epithelialisation of the sutured wound had begun. Immunohistochemical examination showed that, in experimental group 1, the non-uniform epithelial layer of the covered wound surface expressed cytokeratin AE1/AE3, and the epithelial and connective tissue layers stained strongly for FGF-2. Similar results were obtained in experimental group 2, whereas in experimental group 3, FGF-2 was expressed only in the connective tissue layer, and epithelialisation was complete. However, in control group 1, AE1/AE3 was expressed in the epithelial layer, and FGF was expressed in the connective tissue layer beneath the basal layer. In control groups 2 and 3, AE1/AE3 and FGF-2 were expressed in patterns similar to those in experimental groups 2 and 3. We suggest that this method is useful and the operation is simple. However, further testing of the method is needed and it should be widely used clinically before it is recommended.     

兔脂肪干细胞的分离培养鉴定及诱导分化研究

目的:分离培养家兔脂肪干细胞(Adipose-derived stem cells,ASCs),观察体外培养生长特性,并在特定条件下诱导分化,探讨其成脂成骨分化能力。方法:无菌条件下切取家兔腹股沟处脂肪组织,0.25%Ⅰ型胶原酶消化,分离培养原代细胞,取第3代ASCs做实验,用HE染色观察细胞形态,MTT比色法测定细胞生长曲线;用流式细胞仪检测其细胞表面标志物;用油红O染色和茜素红染色鉴定成脂和成骨诱导分化。结果:从家兔脂肪组织中分离获得的ASCs形态为长梭形,成纤维细胞样,生长活力旺盛,具有较强的增殖能力;流式细胞仪分析CD29呈阳性表达,CD31呈阴性表达;成脂诱导的细胞油红O染色阳性,成骨诱导的细胞茜素红染色阳性。结论:本实验分离培养的细胞为ASCs,具有成脂和成骨分化潜能。     

Differential Susceptibility to Experimental Allergic Encephalomyelitis (EAE) in Genetically Defined A+ and A− Rabbits

Only one out of 57 A-/ A- rabbits immunized with rat or guinea-pig myelin developed clinical signs suggestive of EAE. On the contrary, clinical signs of acute or chronic EAE were found in two thirds of the 102 A + /A+ and A + /A - rabbits immunized in the same way. About one third of the diseased animals had reversible acute EAE, another third died paralysed and the last third developed chronic progressive or relapsing EAE. Incidence and severity of EAE symptoms were positively correlated with age and no significant difference was observed between males and females.

Cellular and humoral anti-myelin responses were stronger in A⁺ than in A^? rabbits. Anti-A antibodies, on the contrary, were only detected in A ^? rabbits. The A ⁺ rabbits did not make Anti-A at any time. Anti-A antibodies increased early, in A^? rabbits, after immunization with myelin (11–30 days) and were later replaced by a low, but specific, anti-myelin response (60–90 days).

The gene responsible for the susceptibility to EAE is autosomal and dominant over resistance. This gene must be closely linked to the A locus or might be the A gene itself. The low susceptibility of A^? rabbits to the disease could be, in this last case, a consequence of the competition between the early anti-A and the normal anti-myelin immune responses, both induced by the injection of myelin.