Myelin breakdown in the posterior funiculus of the kitten after dorsal rhizotomy

Summary Morphological aspects of myelin breakdown in the posterior funiculus during Wallerian degeneration were studied in kittens subjected to lumbosacral dorsal rhizotomies 6–8 days after birth. The first sign of myelin breakdown was characterized by swollen or shrunken nerve fibers. Shortly thereafter there was an increased occurrence of collapsed myelin sheaths and later of rounded myelin bodies. Myelin was clearly seen in microglial cells. Correlative observations on Marchi-stained material indicated the simultaneous and frequent appearance of Marchi-positive bodies (MPB:s) and myelin bodies. Due to the rapidity of the degeneration process in the kitten, the increase in the occurrence of Marchi-positive granules (MPG:s) seemed to start concomitantly with increased occurrence of MPB:s. However, the frequent occurrence of MPG:s outlasted that for MPB:s. The findings indicate that the MPB:s may be the counterpart to myelin bodies and the MPG:s to lipid droplets. Microglial cells may be responsible for the primary uptake of degenerating myelin and the subsequent transformation of myelin bodies to lipid droplets. The much faster breakdown of myelin and elimination of lipid material in the degenerating posteror funiculus of the kitten, as compared to the adult, seemed to be due not only to the lower myelin content in the kitten, but also to a higher density of microglia and a greater efficiency in the myelin breakdown process in the degenerating posterior funiculus of the kitten.     

Effect of erythrocyte breakdown products on stem cells and erythropoietin formation

In experiments on CBA mice and albino rats the effect of erythrocyte breakdown products (EBP) on the number of colony-forming units (CFU), differentiation of stem cells, and erythropoietin production was studied. After three or four injections of EBP to normal or lethally irradiated (1000 rad) mice, no changes in the number of CFU or in differentiation of the stem cells were observed after transplantation of bone marrow. Daily administration of EBP to mice for 3 days before irradiation (1000 rad) and bone marrow transplantation led to an increase in the number of colonies in the recipients' spleen, mainly on account of colonies of erythroid type. Injection of EBP into the animals did not change the erythropoietic activity of the blood serum. The possible role of EBP in the mechanism of autoregulation of erythropoiesis is discussed.Division of Experimental Pathology and Experimental Diagnosis, Sverdlovsk Scientific-Research Institute of Tuberculosis. Sverdlovsk Scientific-Research Institute of Work Hygiene and Occupational Diseases. Department of Pathological Physiology, Sverdlovsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Fedorov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 8, pp. 143–145, August, 1977.     

Zygote score and status 1 or 2 days after cleavage and assisted reproduction outcome.

OBJECTIVE: To determine whether pronuclear morphology is a useful additional criterion when selecting embryos for transfer. METHOD: A modified Tesarik and Greco scoring system was used in this retrospective study to assess the pronuclear morphology of 883 zygotes from 214 in vitro fertilization or intracytoplasmic sperm injection cycles. Pronucleus size and presence of cytoplasmic halo were also noted. Embryo selection was performed on Day 2 or 3 following oocyte retrieval. The chi2, analysis of variance, Kruskal-Wallis, and Fisher exact tests were used where appropriate. RESULTS: A stepwise logistic regression revealed that a better embryo quality was associated with both pattern 0 of the scoring system and pronuclei of equal size on Days 2 or 3. Higher pregnancy and multiple gestation rates were obtained when at least 1 embryo classified as pattern 0 was included in the set of embryos transferred. CONCLUSION: Combined with embryo morphology evaluation on Days 2 and 3, a scoring system based on pronuclear morphology seems to provide a good criterion when selecting embryos for transfer.     

Oligogalacturonic acid inhibit bone resorption and collagen degradation through its interaction with type I collagen

In this study, we showed that oligogalacturonic acid (OGA) purified from flax pectin inhibit in vitro osteoclastic bone resorption in a dose-dependent manner. The OGA inhibitory effect was neither linked to an effect on osteoclast apoptosis, nor to an inhibition of cathepsin K activity. By means of an in vitro collagen degradation assay we demonstrated that OGA prevented triple-helical type I collagen cleavage by cathepsin K in a dose and chain length dependent manner. This inhibition was not restricted to cathepsin K, since collagenolytic activity of other lysosomal cysteine proteases, such as cathepsin B and cathepsin L, as well as matrixmetalloproteinases such as MMP-9 were also inhibited. Interestingly, using non-collagen substrates we demonstrated that OGA does not inhibit the proteolytic activity of cathepsin B and L, suggesting that OGA inhibits collagen degradation without affecting the lysosomal cysteine enzyme proteolytic activity. Finally, preliminary study using surface plasmon resonance (SPR) showed that OGA binds to type I collagen but not to albumin, consistent with a specific effect on collagen. These results suggest that the observed inhibition of collagen degradation by OGA may be due to its ability to bind to the collagen molecule. By masking the collagen surface, OGA may render the collagen cleavage site less accessible to enzymes and thus prevent its enzymatic degradation.     

铅对小鼠卵母细胞成熟和体外受精的影响

目的 :探讨铅对小鼠生殖作用的影响。方法 :采用小鼠卵母细胞体外培养、体外受精的方法研究了铅对小鼠卵母细胞的成熟和体外受精的影响。结果 :铅对小鼠卵母细胞生发泡破裂没有影响 ,但可以抑制卵母细胞第一极体的释放 ,影响卵母细胞的存活率并可降低体外受精率和超排卵的卵母细胞数量。随着培养时间的延续 ,卵母细胞的第一极体的释放率和体外受精率都有显著提高。结论 :铅可以破坏卵母细胞减数分裂进行 ,降低卵母细胞的受精能力 ,影响小鼠的正常生殖功能     

Perception of oral food breakdown. The concept of sensory trajectory

Texture perceived in mouth largely depends on the behaviour of the food when it is broken down and transformed by the mouth elements. Texture results from a dynamic process in which texture attributes are continuously analysed by the oral sensory systems during mastication. However, the particular sequence of perceptual events that occur during oral food breakdown remains unknown. The aim of the present study is to describe the succession of perceptual events that happen in mouth during mastication and to show that for each food a texture pathway can be built. This for, we used a sensory method enabling to evaluate the dynamics of texture perceptions during food consumption: the Temporal Dominance of Sensation. On different breakfast cereals, we measured the sensation dominating at each point of the mastication process. We showed that the dynamics of appearance and disappearance of each texture sensation experienced in mouth during the eating process differed among cereals. However, some common features in this sensory trajectory were also observed for the category of products studied. Hardness, crackliness and crispness were rather perceived at the beginning of the mastication period, brittleness and lightness in the middle and stickiness at the end.     

The strategy of group embryo culture based on pronuclear pattern on blastocyst development: a two center analysis

Purpose

To compare two embryo grouping strategies.

Methods

Retrospective time-course analysis in two different centres. Two culture protocols were used at the zygote stage: “Random Group” in which zygotes were randomly grouped and “Definite Group” in which zygotes were grouped based on pronuclear pattern. Embryo culture was extended to blastocyst stage. Primary and secondary outcomes were respectively the blastulation rate and the cumulative clinical pregnancy and implantation rates.

Result(s)

A similar blastulation rate [42 and 41 % day (5 + 6) blastocysts] was obtained in the two groups. Conversely, after adjusting for baseline and cycle variables, cumulative pregnancy [adjusted Odds Ratio = 2.10 (95%CI: 1.08–4.07)] and implantation [adjusted Odds Ratio = 1.78 (95%CI: 1.06–2.97)] rates were significantly higher in the “Random Group” compared to the “Definite Group”.

Conclusion(s)

Two strategies of group culture gave similar results in terms of blastulation rate but the random grouping of zygotes improves pregnancy and implantation rates in IVF-cycles.

Electronic supplementary material

The online version of this article (doi:10.1007/s10815-014-0350-9) contains supplementary material, which is available to authorized users.     

MR3种系统故障解决方案

当线圈ID不能工作,在磁共振系统的SRI功能诊断下排除线圈ID故障问题。当试图运行实时扫描时,系统冲撞壁纸,可以通过一故障修复程序进行清理的实时缓冲文件。当使用MRCE时,发生动态禁用故障,可以通过清理原装DD板上的二极管表面,改变BRM梯度的设置温度等方式来排除故障。     

Recombinant angiopoietin-like protein 4 attenuates intestinal barrier structure and function injury after ischemia/reperfusion

BACKGROUNDIntestinal barrier breakdown, a frequent complication of intestinal ischemia-reperfusion (I/R) including dysfunction and the structure changes of the intestine, is characterized by a loss of tight junction and enhanced permeability of the intestinal barrier and increased mortality. To develop effective and novel therapeutics is important for the improvement of outcome of patients with intestinal barrier deterioration. Recombinant human angiopoietin-like protein 4 (rhANGPTL4) is reported to protect the blood-brain barrier when administered exogenously, and endogenous ANGPTL4 deficiency deteriorates radiation-induced intestinal injury. AIMTo identify whether rhANGPTL4 may protect intestinal barrier breakdown induced by I/R.METHODSIntestinal I/R injury was elicited through clamping the superior mesenteric artery for 60 min followed by 240 min reperfusion. Intestinal epithelial (Caco-2) cells and human umbilical vein endothelial cells were challenged by hypoxia/ reoxygenation to mimic I/R in vitro.RESULTSIndicators including fluorescein isothiocyanate-conjugated dextran (4 kilodaltons; FD-4) clearance, ratio of phosphorylated myosin light chain/total myosin light chain, myosin light chain kinase and loss of zonula occludens-1, claudin-2 and VE-cadherin were significantly increased after intestinal I/R or cell hypoxia/reoxygenation. rhANGPTL4 treatment significantly reversed these indicators, which were associated with inhibiting the inflammatory and oxidative cascade, excessive activation of cellular autophagy and apoptosis and improvement of survival rate. Similar results were observed in vitro when cells were challenged by hypoxia/reoxygenation, whereas rhANGPTL4 reversed the indicators close to normal level in Caco-2 cells and human umbilical vein endothelial cells significantly.CONCLUSIONrhANGPTL4 can function as a protective agent against intestinal injury induced by intestinal I/R and improve survival via maintenance of intestinal barrier structure and functions.