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81.
JA Kiernan 《Biotechnic & histochemistry》2001,76(5):253-255
Here we describe a method for gross staining of gray matter in slices of formaldehyde-fixed human brain. After protection of white matter with 4% phenol at 60°C for 5 min followed by a cold water wash, the gray matter was stained for 10-15 min at 20-25°C with 1% aqueous copper(II) phthalocyanine tetrasulfonic acid tetrasodium salt (CPTS). The staining resisted all attempts to be washed from the gray matter. Stained slices can be stored indefinitely in slightly acidified water, or plastinated as permanent dry specimens. 相似文献
82.
Spontaneous coronary artery dissection is a rare cause of myocardial ischemia or sudden cardiac death. We describe a patient with polycythemia vera and a chronic spontaneous coronary artery dissection who was treated with successful angioplasty and long stenting. 相似文献
83.
Earlier studies have shown that thwarting of feeding behaviour in the laying hen is expressed through a specific vocalisation, the gakel-call. The first aim of this study was to investigate whether the effect of deprivation per se on the occurrence of gakel-calls can be distinguished from the effect of the additional frustration. Frustration is defined as the state of an animal that results from nonreward in the expectancy of reward. The second aim was to investigate whether the occurrence of gakel-calls is restricted to a food context or whether it can be regarded as an expression of frustration in general. For this purpose, 20 hens were deprived of food, water and dustbath. After deprivation at a fixed time, a cue was given and the hens were rewarded with access to food, water or dust during a 15-min session on 4 consecutive days. On the fifth day, they were thwarted in the associated behaviours by blocking the access to these commodities, after the hens had been presented the signal that previously preceded the reward. We then recorded behaviours that might reflect the state of frustration in three 15-min periods. The period "Pre-Frustration" started 15 min before "Frustration". This, in turn, was followed by the period "Post-frustration" in which the hens were rewarded again. Nesting behaviour was thwarted by blocking the access to the nest (Frustration) after a hen had reached the last stage of its prelaying behaviour.In the food, water and dustbath context, deprivation elicited gakel-calls. The additional frustration resulted in a higher number of gakel-calls in all contexts except the food context. However, together with the findings of previous experiments, the results of this study suggest that frustration, in general, is expressed through the gakel-call. Frustration in the nest context elicited more gakel-calls than the other contexts. This latter finding is discussed in the light of the occurrence of the gakel-call under natural circumstances. 相似文献
84.
Bas Brinkhof Helena TA van Tol Marian JA Groot Koerkamp Frank M Riemers Sascha G IJzer Kaveh Mashayekhi Henk P Haagsman Bernard AJ Roelen 《BMC genomics》2015,16(1)
Background
Genes and signalling pathways involved in pluripotency have been studied extensively in mouse and human pre-implantation embryos and embryonic stem (ES) cells. The unsuccessful attempts to generate ES cell lines from other species including cattle suggests that other genes and pathways are involved in maintaining pluripotency in these species. To investigate which genes are involved in bovine pluripotency, expression profiles were generated from morula, blastocyst, trophectoderm and inner cell mass (ICM) samples using microarray analysis. As MAPK inhibition can increase the NANOG/GATA6 ratio in the inner cell mass, additionally blastocysts were cultured in the presence of a MAPK inhibitor and changes in gene expression in the inner cell mass were analysed.Results
Between morula and blastocyst 3,774 genes were differentially expressed and the largest differences were found in blastocyst up-regulated genes. Gene ontology (GO) analysis shows lipid metabolic process as the term most enriched with genes expressed at higher levels in blastocysts. Genes with higher expression levels in morulae were enriched in the RNA processing GO term. Of the 497 differentially expressed genes comparing ICM and TE, the expression of NANOG, SOX2 and POU5F1 was increased in the ICM confirming their evolutionary preserved role in pluripotency. Several genes implicated to be involved in differentiation or fate determination were also expressed at higher levels in the ICM. Genes expressed at higher levels in the ICM were enriched in the RNA splicing and regulation of gene expression GO term. Although NANOG expression was elevated upon MAPK inhibition, SOX2 and POU5F1 expression showed little increase. Expression of other genes in the MAPK pathway including DUSP4 and SPRY4, or influenced by MAPK inhibition such as IFNT, was down-regulated.Conclusion
The data obtained from the microarray studies provide further insight in gene expression during bovine embryonic development. They show an expression profile in pluripotent cells that indicates a pluripotent, epiblast-like state. The inability to culture ICM cells as stem cells in the presence of an inhibitor of MAPK activity together with the reported data indicates that MAPK inhibition alone is not sufficient to maintain a pluripotent character in bovine cells.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1448-x) contains supplementary material, which is available to authorized users. 相似文献85.
86.
87.
TO PUBLICATIONS OF THE SOCIETY FOR APPLIED BACTERIOLOGY 总被引:1,自引:1,他引:0
88.
I Prieto-Potín JA Roman-Blas MJ Martínez-Calatrava R Gómez R Largo Gabriel Herrero-Beaumont 《Arthritis research & therapy》2013,15(4):R81
Objective
The aim of this study was to determine whether hypercholesterolemia increases articular damage in a rabbit model of chronic arthritis.Methods
Hypercholesterolemia was induced in 18 rabbits by administrating a high-fat diet (HFD). Fifteen rabbits were fed normal chow as controls. Chronic antigen-induced arthritis (AIA) was induced in half of the HFD and control rabbits, previously immunized, by intra-articular injections of ovalbumin. After sacrifice, lipid and systemic inflammation markers were analyzed in blood serum. Synovium was analyzed by Krenn score, multinucleated cell counting, immunohistochemistry of RAM11 and CD31, and TNF-α and macrophage chemoattractant protein-1 (MCP-1) gene expression. Active bone resorption was assessed by protein expression of receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG) and quantification of cathepsin K, contact surface and the invasive area of pannus into bone.Results
Rabbits receiving the HFD showed higher total serum cholesterol, HDL, triglycerides and CRP levels than rabbits fed a normal diet. Synovitis score was increased in HFD, and particularly in AIA and AIA + HFD groups. AIA + HFD synovium was characterized by a massive infiltration of RAM11+ cells, higher presence of multinucleated foam cells and bigger vascularization than AIA. Cathepsin K+ osteoclasts and the contact surface of bone resorbing pannus were also increased in rabbits with AIA + HFD compared with AIA alone. Synovial TNF-α and MCP-1 gene expression was increased in AIA and HFD rabbits compared with healthy animals. RANKL protein expression in AIA and AIA + HFD groups was higher compared with either HFD or normal groups.Conclusions
This experimental model demonstrates that hypercholesterolemia increments joint tissue damage in chronic arthritis, with foam macrophages being key players in this process. 相似文献89.
Sacha?Ferdinandusse Hans?R?Waterham Simon?JR?Heales Garry?K?Brown Iain?P?Hargreaves Jan-Willem?Taanman Roxana?Gunny Lara?Abulhoul Ronald?JA?Wanders Peter?T?Clayton James?V?Leonard Shamima?RahmanEmail author 《Orphanet journal of rare diseases》2013,8(1):188
Background
Deficiency of 3-hydroxy-isobutyryl-CoA hydrolase (HIBCH) caused by HIBCH mutations is a rare cerebral organic aciduria caused by disturbance of valine catabolism. Multiple mitochondrial respiratory chain (RC) enzyme deficiencies can arise from a number of mechanisms, including defective maintenance or expression of mitochondrial DNA. Impaired biosynthesis of iron-sulphur clusters and lipoic acid can lead to pyruvate dehydrogenase complex (PDHc) deficiency in addition to multiple RC deficiencies, known as the multiple mitochondrial dysfunctions syndrome.Methods
Two brothers born to distantly related Pakistani parents presenting in early infancy with a progressive neurodegenerative disorder, associated with basal ganglia changes on brain magnetic resonance imaging, were investigated for suspected Leigh-like mitochondrial disease. The index case had deficiencies of multiple RC enzymes and PDHc in skeletal muscle and fibroblasts respectively, but these were normal in his younger brother. The observation of persistently elevated hydroxy-C4-carnitine levels in the younger brother led to suspicion of HIBCH deficiency, which was investigated by biochemical assay in cultured skin fibroblasts and molecular genetic analysis.Results
Specific spectrophotometric enzyme assay revealed HIBCH activity to be below detectable limits in cultured skin fibroblasts from both brothers. Direct Sanger sequence analysis demonstrated a novel homozygous pathogenic missense mutation c.950G <A; p.Gly317Glu in the HIBCH gene, which segregated with infantile-onset neurodegeneration within the family.Conclusions
HIBCH deficiency, a disorder of valine catabolism, is a novel cause of the multiple mitochondrial dysfunctions syndrome, and should be considered in the differential diagnosis of patients presenting with multiple RC deficiencies and/or pyruvate dehydrogenase deficiency.90.
Loes?AM?Leenen Ben?FM?WijnenEmail author Reina?JA?de Kinderen Marian?HJM?Majoie Caroline?M?van Heugten Silvia?MAA?Evers 《BMC neurology》2014,14(1):255