Photolysis and ozonolysis of (iso) desmosine-containing crosslinked peptides from porcine aorta elastin

This report describes the use of photolysis and ozonolysis as a means of achieving complete cleavage of the pyridinium ring of (iso)desmosine in crosslinked elastin peptides. Although photolysis leads to the opening of the ring with concomitant formation of lysine, the peptide chains remain attached. Subsequent ozonolysis is able to completely achieve the cleavage of the rest of the ring skeleton, thus leading to the separation of the peptide chains. Formation of new amino acids, i.e. α-aminoadipic and glutamic acids, is emphasized. Localization of these amino acids within the released peptides should be of help in structural investigations on the crosslinking zones involving either isodesmosine or desmosine. However, other amino acids such as tyrosine and phenylalanine are sensitive to this procedure and side reactions occur which are responsible for peptide bond cleavage with the formation of breakdown products.     

Radiofrequency Current Ablation of Porcine Right Atrium: Increased Lesion Size with Bipolar Two Catheter Technique Compared to Unipolar Application In Vitro and In Vivo

Interruption of atrial flutter and fibrillation by RF catheter ablation may be favored by large, elongated lesions. We administered RF current in unipolar and bipolar mode in porcine right atrium. Bipolar ablation was performed between the tip electrodes of two serially coupled catheters. With 4-mm tip electrodes in vitro, lesion length increased from a mean (SD) of 7.9 (1.2) mm at 3 mm-interelectrode distance (IED) to 13.3 (3.3) mm at 9-mm IED, but decreased at 12-mm IED due to nonconfluent lesions (P < 0.0001), With 4 mm distal electrodes and 8 mm IED, bipolar lesions were 65% longer than corresponding unipolar ablations. Switching to bipolar mode increased the lesion length more than increasing electrode tip length to 6 mm in unipolar mode. Power and temperature controlled ablation created equally sized lesions. Twelve anesthetized pigs were randomized to unipolar or two catheter bipolar temperature controlled ablation of the right atrial free wall. Bipolar ablation created confluent lesions with endocardial length × width of 13.5 (5.8) × 7.3 (3.7) mm, unipolar ablation 6.4 (2.8) × 4.6 (1.4) mm (P < 0.001 when comparing length and P = 0.013 for lesion width). The atrial lesions in both groups were transmural and extended into hilar lung lesions with maximal depth of 3.0 (1.1) and 2.6 (1.0) mm, respectively (P = 0.44). Five bipolarly and four unipolarly ablated pigs developed right diaphragmal paresis. We conclude that bipolar ablation may be preferable in situations where large, elongated lesions are favorable. The two catheter technique is feasible in porcine right atrium. Both bipolar and unipolar ablation of the porcine right atrial free wall may frequently be complicated by injury to the phrenic nerve and adjacent lung tissue.     

Capacitation-dependent concentration of lipid rafts in the apical ridge head area of porcine sperm cells

Lipid architecture of the plasma membrane plays an important role in the capacitation process of the sperm cell. During this process, an increase in membrane fluidity takes place, which coincides with a redistribution of cholesterol to the apical region of the head plasma membrane and subsequently an efflux of cholesterol. Cholesterol is also a major player in the formation of lipid rafts or microdomains in the membrane. Lipid rafts favour specific protein-protein interactions by concentrating certain proteins in these microdomains while excluding others. In this study, we investigated the organization of lipid rafts during in vitro capacitation of boar sperm cells. We report on the presence of the lipid raft-specific proteins caveolin-1 and flotillin-1 in sperm cells. Capacitation induced a change in membrane distribution of these proteins. Lipid analysis on detergent-resistant membranes (DRMs) of sperm cells indicated that capacitation induces a lipid raft concentration rather than a disintegration of lipid rafts, because the total amount of lipid in the DRM fraction remained unaltered. Using a proteomic approach, we identified several major DRM proteins, including proteins involved in capacitation-dependent processes and zona pellucida binding. Our data indicate that sperm raft reorganization may facilitate capacitation-specific signalling events and binding to the zona pellucida.     

静态与动态下脱细胞猪主动脉瓣种植人成纤维细胞初步研究

目的 探索在脱细胞猪主动脉瓣膜材料上种植人成纤维细胞的方法与效果；材料和方法 采用在脱细胞猪主动脉瓣膜材料上静态与动态种植人成纤维细胞，并对其结果进行比较研究。结果 静态种植不能在猪主动脉瓣叶的两侧形成完整的单层人成纤维细胞融合层；而经过动态种植，在一定条件下可以在猪主动脉瓣叶两侧形成完整的单层人成纤维细胞融合层；结论 动态种植较之静态种植易达到形成完整均匀的细胞种植效果。     

家猪心脏纤维支架的大体解剖

目的　观察猪心纤维支架 ,为猪心的研究和比较解剖学积累资料。方法　取甲醛固定后的猪心2 7例 ,液态塑料浸渍的塑化猪心 5例 ,解剖显示纤维支架后用游标卡尺进行观测。结果　猪心左纤维三角的三边分别平均为 17 4 1± 1 99mm、18.96± 3.2 6mm和 17.6 4± 2 .4 4mm ;右纤维三角三边分别为 15 .83± 2 .11mm、16 .19± 1.94mm和 2 0 .96± 2 .6 2mm ;二尖瓣环、三尖瓣环的周长平均为 73.0 0± 9.71mm ,6 8.89±7.2 4mm ;主动脉瓣环和肺动脉瓣环直径分别为 18.4 4± 2 .89mm和 16 .0 3± 2 .6 3mm ;猪Todaro腱呈扁带状 ,走行部位较深 ,且分支较人心多 ,长度为 2 0 98± 4 2 0mm。结论　猪心纤维支架与人类形态结构相似 ,但瓣环周长和Todaro腱形态有一定差别。     

家猪心脏三尖瓣复合体的形态学观测

目的　观测家猪心脏三尖瓣复合体 ,为家猪心脏研究和心脏移植积累资料。方法　甲醛固定的家猪心脏 35例 ,大体解剖并观测三尖瓣复合体。结果　家猪心脏三尖瓣复合体由瓣环、瓣膜、腱索和乳头肌构成 ,瓣环周长为 70 75± 8 4 5mm ,前瓣、后瓣、隔侧瓣、前隔连合、前后连合、后隔连合的高度分别为 14 5 8±2 6 4、14 16± 2 5 0、12 84± 2 37、6 2 9± 1 97、6 86± 1 0 1、6 5 1± 1 36mm。前隔连合、前后连合、后隔连合的宽度分别为 6 4 0± 1 5 4、6 78± 1 2 3、6 4 3± 1 4 6 ;前乳头肌起始 ,腱索附着于前瓣、后瓣和前后连合的条数分别为 3 0 0± 0 97、3 0 9± 1 0 9、2 4 4± 1 16 ;后乳肌起始 ,腱索附着于后瓣、隔侧瓣和后隔连合的条数分别为 2 6 0± 0 6 9、3 0 9± 1 6 3、1 14± 0 4 3。隔侧乳头肌起始 ,附着于前瓣、隔侧瓣、前隔连合的腱索条数分别为1 71± 0 6 7、2 37± 1 2 6、0 94± 0 4 2。结论　家猪心脏三尖瓣复合体中各结构与人类相似 ,但大小有一定差异。     

Immunohistochemical labelling of cytokines in lung lesions of pigs naturally infected with Mycoplasma hyopneumoniae

Mycoplasma hyopneumoniae (Mh) is the primary agent of porcine enzootic pneumonia (PEN), a chronic respiratory disease endemic to pig farms, and characterized histologically by infiltration of mononuclear cells in airways and prominent hyperplasia of the bronchus-associated lymphoid tissue (BALT). To gain further insight into the pathogenesis of PEN, cytokine expression in the lung, with particular attention to the BALT, was examined immunohistochemically in pigs naturally infected with Mh. An increase (P < 0.05) in proinflammatory and immunoregulatory cytokines (especially interleukin [IL]-2, IL-4 and tumour necrosis factor [TNF]-alpha, and to a lesser extent IL-1 [alpha and beta] and IL-6) was detected in the BALT, which showed intense lymphoid hyperplasia. IL-1beta and TNF-alpha were also detected in the bronchoalveolar exudate of infected pigs, and IL-6 and IL-8 were demonstrated in mononuclear cells of the alveolar septa. The results showed that in Mh infection, macrophage and lymphocyte activation results in the expression of a number of cytokines capable of inducing lung lesions and lymphoreticular hyperplasia of the BALT.     

静电法制备小微囊包裹成年猪胰岛的实验研究

目的　探索用静电法制备小微囊包裹成年猪胰岛细胞。方法　用自制的静电微囊发生装置、制备海藻酸钠 -多聚赖氨酸 -海藻酸钠 (APA)微囊 (微囊直径 <35 0 μm) ,包裹成年猪胰岛 ,体外检测APA小微囊猪胰岛生物活性及微囊膜的通透性 .结果　静电法制备的APA微囊直径 30 0～ 35 0 μm ,大小相对均一 .小微囊包裹成年猪胰岛后 ,每个微囊内可见 1～ 2个胰岛团 ,表面光滑 .囊内胰岛组织学结构完整 ,体外培养微囊化胰岛素分泌良好 ,葡萄糖刺激释放明显 ,显示了良好的细胞活力及微囊膜通透性 .结论　用我们自制的静电微囊发生装置能制备APA微囊包裹成年猪胰岛细胞 ,微囊直径 30 0～ 35 0 μm ,表面光滑 ,囊内猪胰岛生物活性良好     

Identification of the membrane protein of porcine epidemic diarrhea virus

Sequence information on the genome of porcine epidemic diarrhea virus (PEDV) has only recently been determined. In contrast, very little is known about the viral proteins. In the present report we have identified the membrane glycoprotein (M) of PEDV by use of rabbit anti-peptide sera and transient expression of the cloned M gene in Vero cells and by expression in the baculovirus system. The native M protein of PEDV is incorporated into virions, is N-glycosylated, and migrates with a relative mobility (Mr) of 27 k in polyacrylamide gels. In contrast, the M protein synthesized by recombinant baculoviruses migrates with a Mr of 23 k, that is, with identical mobility as the deglycosylated product of PEDV. Thus, it appears that M protein specified by the recombinant baculovirus is poorly, if at all, glycosylated. Using monoclonal antibodies and rabbit antipeptide sera specific for the N and C termini of the M protein, we were able to show that a 19 k band detected in PEDV-infected cells but not in virions represented a fragment of M from which the C terminus had been cleaved off. Finally, by electron microscopy and immunogold labelling, the relative orientation of M within the virion envelope was determined as NexoCcyt. In conclusion, all of these data strongly support the hypothesis that PEDV should be classified with the group I coronaviruses.