猪急性冠状动脉微栓塞模型的建立

目的　应用微导管介入技术建立小型猪急性冠状动脉微栓塞（CME）模型。方法　巴马系小型猪随机分为假手术组和微栓塞组（CME组）;CME组再按微球数目不同分为5万、10万、15万、25万微球亚组（各组存活小型猪均为5头）。CME组通过经皮冠状动脉介入法,于前降支中远端,经微导管注入微栓塞球,假手术组注射生理盐水,各组术后9　h分别应用心脏超声检测心功能,HE染色和苏木素碱性复红苦味酸（HBFP）染色检测心肌微梗死面积。结果　①超声心动图参数显示,与假手术组比较,5万微球组心功能无明显改变（P>0.05）;与假手术组比较,10万微球组、15万微球组、25万微球组左心室射血分数（LVEF）均显著下降（P<0.05）,心脏超声表现为左心室短轴缩短率（FS）和心排血量（CO）下降及左心室舒张期末内径（LVEDd）增加。②CME各组均出现心肌微梗死灶,与5万微球组（4.62%±2.17%）比较,10万微球组（9.23%±3.97%）、15万微球组（12.24%±4.73%）、25万微球组（21.52%±6.19%）微梗死面积均明显增加（P<0.05）;③不同CME组之间比较,LVEF与微栓塞球数目成负相关（r－0.74,P<0.05）、心肌微梗死面积与微栓塞球数目成正相关（r0.87,P<0.05）。④心肌HE、HBFP染色示：10万微球组基本在每张切片均可发现微梗死灶,并且不引起大面积的心肌梗死。结论　经微导管于左前降支中段注射10万计数微球可以成功制作小型猪急性CME模型。     

Kinetic determination of malate dehydrogenase isozymes

These studies determine the levels of malate dehydrogenase isoenzymes in cardiac muscle by a steady state kinetic method which depends on the differential inhibition of these isoenzyme forms by high concentrations of oxaloacetate. This inhibition is similar to that exhibited by lactate dehydrogenase in the presence of high concentrations of pyruvate. The results obtained by this method are comparable in resolution to those obtained by CM-Sephadex fractionation and by differential centrifugation for the analyses of mitochondrial malate dehydrogenase and cytoplasmic malate dehydrogenase in tissues. The use of standard curves of percent inhibition of malate dehydrogenase activity plotted against the ratio of mitochondrial MDH activity to the total of mMDH and cMDH activities [$\text{m}\text{(m + c)}$ malate dehydrogenase ratio] (percent m-type) is introduced for studies of comparative mitochondrial function in heart muscle of different species or in different tissues of the same species.     

猪胸主动脉的零应力状态研究及其临床意义

目的　探讨猪胸主动脉的生物力学特性变化。方法　取 1～ 9月龄猪的胸主动脉各 6例 ,从每例标本的中段处将血管切为短圆环 ;将 7月龄猪胸主动脉分为上、中、下段 ,每段再分为 5个短圆环。将各血管沿其径向剪开 ,测量张开角的大小、壁厚和周长 ,并依周长计算出等效内径。结果　猪胸主动脉张开角由 1月的 (42 .1 7± 4 .0 6)°上升到 7月的 (76.2 2± 4 .4 0 )°,在 7月龄后达到稳定。对 7月龄猪胸主动脉自上而下分析则发现张开角由 (99.73± 6.79)°降至 (42 .0 9± 7.4 0 )°。壁厚 等效内径值随月龄增加而减小 ,于 7月龄后保持于 0 .1 8左右。结论　猪胸主动脉张开角、等效内径和壁厚随月龄的增加而增大 ;随着X L的增加各项指标均逐渐减小 ,血管的内外径在 7月龄后成比例生长。为猪→人异种血管移植和血管的病理改变后修复与功能重建提供依据     

The pig mesonephros

Summary The ultrastructure of the proximal tubule of mature mesonephric nephrons was studied in perfusion-fixed pig embryos of the 41st gestational day. Despite its 8–12 mm long course, the proximal tubule possesses no cytologically different subsegments except its very last cells at the abrupt transition into the distal tubule. The first brush-bordered proximal tubule cells stand considerably within Bowman's capsule, abuting its attenuated cells. In SEM specimens, the average luminal cell diameters are 8×13 m. The cells are 6–11 m in height with overlying microvilli 2–4 long. Lateral faces of perfectly disjoined cells exhibit plate-like interdigitating processes projecting more than 5 m deep into the neighboring cells. The basal cell face is completely covered with microvilli. The TEM pictures reveal an endocytic apparatus largely matching its metanephric counterpart. Mitochondria account for 23% of the cytoplasm and together with the many basolateral cell membranes indicate a high capacity for energy-dependent transport processes. Small basal lipid droplets represent a species peculiarity. Freeze-fracture specimens show an electrocoupling of the cells by gap junctions. The tight junction, with only 1–2 strands, characterizes a leaky epithelium. In most features, this tissue is as mature as its metanephric counterpart.Supported by the Deutsche Forschungsgemeinschaft.     

Oogonia and oocytes degeneration and the nutritive macrophages in the process of the development of the ovary in embryos of the domestic pig (Sus scrofa dom. L.)

Summary In the development the embryonic ovary numerous oogonia and oocytes degenerate. A histochemical study was carried out on the degenerated oogonia and oocytes in different stages of differentiation and development of the ovary in the pig embryos. In the oogonia the degenerative changes include chiefly the chromatin in interphasic and mitotic nuclei. The most numerous degenerations of the nuclei are in meiotic prophase. The degenerative process involves the changes in nuclear volume. Both, the large swollen nuclei, with chromosomes displaced and clustered at one pole, and also the small pycnotic nuclei are observed. Different kinds of oocytes degenerations are discussed.Special attention was paid to the gonadal cord cells and their role in nutrition of gonocytes and in the follicle formation. Some of the cord cells are transformed into macrophages, which ingeste degenerated oocytes. The supposed nutritive functions of these macrophages (nutritive macrophages) are discussed.     

Clofibrate treatment up-regulates novel organic cation transporter (OCTN)-2 in tissues of pigs as a model of non-proliferating species

Recent studies have shown that treatment of rodents with agonists of peroxisome proliferator-activated receptor (PPAR)-alpha causes an up-regulation of novel organic cation transporter (OCTN)-2, a carnitine transporter, and increases carnitine concentration in the liver. This study was performed to investigate whether such effects occur also in pigs which like humans have a lower expression of PPAR alpha and are less responsive to treatment with PPAR alpha agonists than rodents. An experiment with 18 pigs was performed which were fed a control diet or the same diet supplemented with 5 g clofibrate/kg for 28 days. Pigs treated with clofibrate had higher relative mRNA concentrations of OCTN2 in liver (3.1-fold), skeletal muscle (1.5-fold) and epithelial cells from small intestine (1.8-fold) than control pigs (P<0.05). Pigs treated with clofibrate had also higher concentrations of free and total carnitine in the liver and a higher concentration of free carnitine in skeletal muscle than control pigs (P<0.05). Concentrations of gamma-butyrobetaine, the precursor of endogenous formation of carnitine, in liver, muscle and plasma did not differ between both groups; the activity of gamma-butyrobetaine dioxygenase, the rate limiting enzyme of carnitine synthesis, in the liver was lower in pigs treated with clofibrate than in control pigs (P<0.05). This study shows for the first time that treatment with a PPAR alpha agonist causes an up-regulation of OCTN2 in liver, muscle and enterocytes from small intestine of pigs. This in turn increases carnitine concentrations in liver and muscle probably by enhancing carnitine uptake into cells.     

成年猪胰岛的分离与纯化

目的　研究成年猪胰岛的分离与纯化方法。方法　胰岛的分离采用导管内连续灌注胶原酶消化法 ,纯化采用Nycodenz连续密度梯度离心。 结果　消化后每个胰腺平均可获得 (3970 0 0±185 96 3)个胰岛或 (986 0± 3 0 43)个胰岛 /克胰腺组织 ,纯化后为 (1480 0 0± 890 0 0 )个胰岛 /胰腺或(3 75 0± 493)个胰岛 /克胰腺组织 ,纯度 >95 %。体外培养示胰岛对糖刺激反应良好 ;免疫组织化学检查证实胰岛细胞存活。结论　经本法获得的胰岛具有较高的纯度及良好的功能 ,可为临床提供可靠的移植物来源。     

猪胆总管脱细胞基质构建组织工程胆管的生物力学评价

目的　用不同的脱细胞方法对猪胆总管进行处理,比较脱细胞前后的生物力学变化,筛选适宜的脱细胞方法,为组织工程胆管支架材料的应用提供理论依据。 方法　30例猪胆总管,随机分为5组,A组：对照组, B组：0.05 % 胰蛋白酶+核酸酶,C组：0.1 % SDS+核酸酶,D组：1.0 % Triton X-100+核酸酶,E组：1.0 % Triton X-100+0.1 % SDS +核酸酶。在Test Resources生物力学试验机上进行加载一卸载试验和极限抗张强度试验。计算出生物力学材料常数（α1、β1、α2、β2）、弹性模量、极限抗张强度和断裂伸长率等指标。 结果　Ｄ组、Ｅ组的生物力学材料常数（α1、β1、α2、β2）与A组的差异无统计学意义（F = 12.21, P = 0.06）,Ｂ组、C组比A组、D组和Ｅ组的小（P < 0.01）;Ｄ组、Ｅ组的弹性模量比A组的稍增大,但差异不明显（P > 0.05）,Ｂ组、C组比A组的小（P < 0.05）;Ｄ组、Ｅ组的UTS值和SOF值与A组差异不明显（P > 0.05）;B组、C组的UTS值明显小于A组（P < 0.05）,SOF值明显大于A组（P < 0.05）。 结论 应用1.0 % Triton X-100+核酸酶和1.0 % Triton X-100+0.1 % SDS +核酸酶的脱细胞效果好,且不会影响猪胆总管的生物力学特性,是一种比较理想的猪胆总管脱细胞方法。     

3D技术打印椎体在全脊椎整块切除术中应用的初步探索

目的初步探索3D技术打印椎体在全脊椎整块切除术(Total en bloc spondylectomy,TES)中应用的可行性。方法选取广东紫金蓝塘土猪3只,T12、L1椎体进行后路全椎体切除术,置入3D打印假体,于T11、L2进行双侧椎弓根螺钉固定。观察术后土猪活动度、脊柱影像、双后腿痛觉和肌力。术后4月时处死,观察实体标本情况。结果手术成功,术后猪双后腿活动、痛觉良好。正侧位X片及CT三维重建,实物脊柱3D打印椎体-脊柱复合体观察,提示假体位置、椎间高度、脊椎序列完好。结论 3D技术打印椎体在临床脊柱全椎体切除术中的应用具有可行性,但需充分做好术前准备,如抗感染、补充血容量、假体型号合适、手术器械齐全等,才能保证手术的顺利完成。