实验性兔主动脉粥样硬化易损斑块模型的建立与评价

目的探索建立实验性兔主动脉粥样硬化易损斑块模型的新方法。方法24只雄性日本大耳白家兔随机分为对照组8只,实验组16只,对照组给予普通饲料;实验组给予高胆固醇饲料、注射牛血清白蛋白及进行腹主动脉球囊拉伤术,分别于0周、3周、6周、10周检测血脂、ox-LDL、TNF-α、IL-1、IL-10,实验结束时取腹主动脉进行病理形态学分析及NF-κBp65亚基免疫组化染色分析。结果实验组斑块内膜面积比为53.6%,脂核面积与斑块面积比为54.9%,斑块纤维帽厚度与内膜中膜厚度（IMT）比约为8.5%;除甘油三酯变化不大外,实验组TC、LDL-C、HDL-C、LDL-C/HDL-C、TC/HDL-C、ox-LDL、TNF-α、IL-1、IL-10均有明显升高趋势,在3周、6周、10周时与对照组比较差异有统计学意义;且NF-κBp65亚基阳性染色面积较对照组高13.5倍。结论高脂喂养、免疫损伤加球囊拉伤可以成功建立家兔主动脉粥样硬化易损斑块模型。     

感染流行性出血热病毒家兔病毒血症的研究

本文采用流行性出血热病毒114株实验感染家兔,用免疫荧光法及病毒培养技术研究了家兔病毒血症动态,发现感染后第6天,病毒抗原首先在淋巴细胞及单核细胞中出现;次日,亦可见于粒细胞中,第10—12天的抗原反应较强,第15天则明显减弱至消失。而在红细胞及血小板中始终未见明显的抗原反应。从感染后第3—13天的血浆中分离出病毒;感染后第6—15天,外周血单核细胞病毒分离阳性。结果表明,流行性出血热病毒在接种局部增殖后,侵入血液,并在白细胞中复制增殖,可能使病毒随血循环播散至全身其它组织脏器,造成因血传播引起的靶器官感染。     

Viability and acrosome integrity of rabbit spermatozoa processed in a gelatin-supplemented extender

The effect of gelatin addition to the semen extender on the viability and acrosome integrity of rabbit spermatozoa was studied. Pooled semen samples were processed in a boar semen extender with or without gelatin addition. Semen samples were stored at 5 °C for 72 h. Viability and acrosome integrity was evaluated by light microscope. Results showed that gelatin addition had a significant positive effect on the quality of the stored semen.     

Measurement of extracellular pH,K(+), and lactate in ischemic heart

Simultaneous and continuous measurements of extracellular pH, potassium (K(+)), and lactate (L(-)) in ischemic rabbit papillary muscle are presented for the first time. Potentiometric pH and K(+) sensors and an amperometric lactate biosensor were used. These miniature electrodes were previously developed and individually tested for this purpose. The pH sensor was based on an iridium oxide layer electrodeposited on a planar platinum electrode fabricated on a flexible substrate. The potentiometric K(+) sensor was based on a polymeric membrane and valinomycin ionophore. The L(-) biosensor was based on lactate oxidase and an organic conducting salt polarized at 0.15V vs Ag/AgCl reference electrode. The utility of this novel analytical system to cardiovascular research was demonstrated by using the system to study the interrelationship of cellular K(+) and lactate loss in ischemic myocardium, and the role of extracellular pH and buffer capacity on this relationship. The results indicated: (i) sequential brief episodes of ischemia produced reproducible trends of L(-), pH, and K(+) changes during the first three episodes, (ii) extracellular L(-) increased with increasing buffer capacity of extracellular compartment, (iii) the patterns of extracellular L(-) and K(+) changes were not related directly, and (iv) L(-) transport and lactic acid diffusion were not the primary cause of extracellular acidosis during ischemia.     

Purinergic regulation of glucose and glutamine synthesis in isolated rabbit kidney-cortex tubules

The effects of extracellular purinergic agonists and their breakdown products on glucose and glutamine synthesis in rabbit kidney-cortex tubules incubated with aspartate + glycerol or alanine + glycerol + octanoate were investigated. A rapid extracellular degradation of ATP was accompanied by an accumulation of AMP, inosine, and hypoxanthine. Extracellular ATP and its breakdown products accelerated glucose synthesis in renal tubules, while ammonium released from adenine-containing compounds enhanced glutamine synthesis and diminished the degree of gluconeogenesis stimulation. In contrast to AMP and inosine, ATP evoked calcium signals, while both ATP and inosine decreased intracellular cAMP content and accelerated the flux through fructose-1,6-bisphosphatase as concluded from changes in gluconeogenic intermediates. Since (i) the activity of partially purified renal fructose-1,6-bisphosphatase was increased upon protein phosphatase-1 treatment and decreased following treatment of previously dephosphorylated enzyme with protein kinase A catalytic subunit and (ii) both 8-bromoadenosine 3',5'-cyclic monophosphate and 8-(4-chlorophenyltio)-cAMP inhibited renal glucose synthesis, it seems likely that in rabbit renal tubules ATP and inosine stimulate gluconeogenesis via cAMP decrease, which favors the appearance of a more active, dephosphorylated form of fructose-1,6-bisphosphatase, a key gluconeogenic enzyme.     

Articular cartilage reconstruction using xenogeneic epiphyses slices

Reconstruction of articular cartilage defects using adult osteochondral allografts is an established clinical procedure, whose principal drawback is lack of lateral integration of the grafts to the surrounding tissue. Autologous chondrocytes transplantation is a sophisticated technique requiring cell culture and a staged operation. Its main draw back is the lack of mechanical strength early on. This study was conducted in order to evaluate the possibility of using embryonal epiphyses as a cartilage reconstruction tissue. A xenogeneic human to rabbit sub-acute osteochondral defect model was designed to evaluate the possibility of allogeneic implantation in humans. The following procedures were perfomed (n = 5): transplantation of 1. live epiphyses 2. live epiphyses with autogeneic periosteum 3. de-vitalized epiphyses and 4. devitalized epiphyses with autogeneic articular chondrocytes. A fifth control group did not receive any implant. Animals in groups 1 and 2 had a viable reconstruction of the articular surface with little evidence of rejection and without pannus formation. Animals in groups 3 and 4 became severely arthritic and the graft was resorbed. Nitric oxide synthase accumulation was reduced in group 1 and 2 as compared to groups 3, 4, and 5, indicating a joint preserving function of the epiphyseal grafts. Epiphyseal grafts appear to be a feasible procedure for reconstruction of articular cartilage defects even in a xenogeneic model. This revised version was published online in July 2006 with corrections to the Cover Date.     

Relationships between growth at the sutures of the rabbit calvarium

The present study was designed to elucidate the relationships between growth increments at the cranial vault sutures in rabbits. Thirteen male New Zealand white rabbits were followed regularly from age 31 to 142 days using a roentgen stereophotogrammetric system. Spherical tantalum markers were implanted into the nasal, frontal, and parietal bones, and implant stability was checked at each stereo examination. Problems with instability were encountered only in the nasal bones. Registered growth rates conformed to our previous investigations. High correlations were observed between the following areas; the coronal suture to the frontonasal suture, the first principal component of the neurocranial suture group to the frontonasal suture, and the principal component of the craniofacial suture group to the coronal suture. Remaining relationships demonstrated dispersion to various extents. The findings indicate that there seems to exist a basic mutual dependence between neural and facial skeletal growth, as well as complex covariations between the various sutures of the rabbit calvarium.     

兔内毒素性急性肺损伤肺内NOS阳性细胞数及超微结构的变化

目的　从病理学和组织化学角度观察内毒素性肺损伤时肺组织超微结构和 NOS阳性染色细胞数的变化。方法　采用电镜、还原型辅酶 - -黄递酶 (NADPH- d)组织化学技术观察兔内毒素性急性肺损伤时肺组织超微结构的改变和肺内小血管、细小支气管、肺泡的 NOS阳性染色细胞数目的变化。结果 :内毒素注射后观察 30分钟组 (I3 0′组 )与内毒素注射后观察 1周组 (Iw 组 ) ,肺内小血管、 NOS阳性染色细胞数明显增多 ,细小支气管和肺泡则减少。 I3 0′组与 Iw 组分别与 C组比较 :(小动脉 :I3 0 vs C,P<0 .0 1;Iwvs C,P<0 .0 0 1;小静脉 :I3 0 vs C,P<0 .0 1;Iw vs C,P<0 .0 5 ;细小支气管 :I3 0vs C与 Iwvs C均为 P<0 .0 2 ;肺泡 :I3 0 vs C与 Iwvs C均为 P<0 .0 1)。电镜结果显示 ,I3 0′组部分肺毛细血管内见有大量红细胞集聚 ,毛细血管内皮变薄 ,微细结构不甚清楚 ,Iw组部分毛细血管内皮细胞损伤状况较 I3 0′组更显严重 ,除较多见红细胞渗入肺泡腔外 ,尚见部分肺泡上皮结构不甚完整而呈泡状改变。结论　内毒素性肺损伤 ,肺内 NOS阳性染色细胞数在小血管明显增加 ,在支气管内 ,肺泡内则明显减少。     

Identification of the hemoglobin binding sites on the inner surface of the erythrocyte membrane

The hemoglobin binding sites on the inner surface of the erythrocyte membrane were identified by measuring the fraction of hemoglobin released following selective proteolytic or lipolytic enzyme digestion. In addition, binding stoichiometry to and fractional hemoglobin release from inside-out vesicle preparations of human and rabbit membranes were compared since rabbit membranes differ significantly from human membranes only in that they lack glycophorin. Our results show that rabbit inside-out vesicles bind about 65% less human or rabbit hemoglobin under conditions of optimal and stoichiometric binding, despite being otherwise similar in composition. We suggest that this difference is either directly or indirectly due to the absence of glycophorin in rabbit membranes. Further supportive evidence includes demonstrating (a) that neuraminidase treatment of human membranes did not affect hemoglobin binding and (b) that reconstitution of isolated glycophorin into phospholipid vesicles increased the hemoglobin binding capacity in a manner proportional to the fraction of glycophorin molecules oriented with their cytoplasmic sides exposed to the exterior of the vesicle. Proteolysis of human inside-out vesicles either before or after addition of hemoglobin reduced the binding capacity by about 25%. This is consistent with the known proportion of total hemoglobin binding sites involving band 3 protein and the selective lability of the cytoplasmic aspect of band 3 protein to proteolysis. Phospholipid involvement in hemoglobin binding was determined using various phospholipase C preparations which differ in their reactivity profiles. Approximately 38% of the bound hemoglobin was released upon cleavage of phospholipid headgroups. These results suggest that the predominant sites of binding for hemoglobin on the inner surface of the red cell membrane are the two major integral membrane glycoproteins.     

Kubelka—Munk模型下的兔血管对He—Cd激光的散射与吸收特性

测量了兔动脉和静脉夺He-Cd激光的反射和透射传输特性。实验采用两积分球系统及波长为441.6nm的He-Cd激光器,并根据测量数据及采用Kubelka-Munk模型分析和计算了兔动脉和静脉组织对该波长激光的吸收系统、散射系数及总的光强I（x）及前向散射通量i(x)和后向散射通量j(x）随厚度的变化情况。结果表明,兔动脉和静脉的温反射率和透射率有明显差别,而且,动脉对激光的吸收系数明显较静脉的要小,耐动脉对激光的散射系数却明显较静脉的要大,在动脉和静脉组织中总的光强I(x)及前向散射通量i(x)和后向散射通量j(x)随厚度的变化情况也有明显的区别。