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Mitochondrial dysfunction is a hallmark of beta-amyloid (Abeta)-induced neuronal toxicity in Alzheimer's disease (AD). Here, we demonstrate that Abeta-binding alcohol dehydrogenase (ABAD) is a direct molecular link from Abeta to mitochondrial toxicity. Abeta interacts with ABAD in the mitochondria of AD patients and transgenic mice. The crystal structure of Abeta-bound ABAD shows substantial deformation of the active site that prevents nicotinamide adenine dinucleotide (NAD) binding. An ABAD peptide specifically inhibits ABAD-Abeta interaction and suppresses Abeta-induced apoptosis and free-radical generation in neurons. Transgenic mice overexpressing ABAD in an Abeta-rich environment manifest exaggerated neuronal oxidative stress and impaired memory. These data suggest that the ABAD-Abeta interaction may be a therapeutic target in AD.  相似文献   
63.
T. Tsuchiya 《Euphytica》1973,22(3):592-599
Summary Bulk seeds of each of nine strains of hexaploid triticale were classified according to size by passing them over four round-holed sieves, 8/64, 9/64, 10/64 and 11/64-inch mesh. The actual size was different in different strains depending on the characteristic seed size of the strain (Table 2). Of the nine strains, six had low aneuploid frequency (11.8% average) and three had high aneuploid frequency (39.0% average) in the bulk populations. Chromosome numbers were counted in root-tip mitosis of germinating seeds.The frequency of euploids was highest in large-seed classes in all but one strain, UM 6608 (Group F). The euploid frequency was variable in medium- and small-seed classes. It was suggested that the screening of larger seeds would give a higher frequency of euploids, particularly in most populations with a low frequency of aneuploids.  相似文献   
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We herein present clinical findings of an Iriomote cat with Hepatozoon felis parasitemia. A male Iriomote cat was captured for ecological analyses three times from January 2010 to January 2011. Although this cat did not show any hematological abnormalities at the time of the first capture, H. felis parasitemia and increased serum creatine kinase levels were detected at the second and third captures. H. felis infection was confirmed by polymerase chain reaction, and amplified 18S ribosomal RNA gene fragments were 100% identical to those of H. felis in leopard cats in Korea. Although the virulence of H. felis in this cat was suggested to be low, this is the first report of an H. felis-infected Iriomote cat with parasitemia.  相似文献   
66.
New perspectives on aquarium fish trade   总被引:1,自引:0,他引:1  
ABSTRACT:   Since the 1990s, the international market for importing aquarium fish is suspicious of stock coming from South-East Asia. Fish catches are still executed with cyanide-based toxic products. In the present paper, the potential of the French Polynesian Islands to develop a marine aquarium fish business with a new approach is explored. Coral reef fish are captured at the larval stage with crest nets, then larvae are reared in aquaria before being put on the world ornamental fish market. This approach offers several advantages: (i) larvae are captured with a passive system placed on the reef crest (crest net) that does not destroy the environment and limits the stress on collected larvae; (ii) larvae are then put into farmed basins that allow them to be controlled sanitarily; and (iii) larvae are weaned at the farm and fed rapidly with artificial food. This method increases survival rates as it eliminates the food acclimatization problem of fish captured at adult stage (main cause of fish mortality in aquaria). Overall, reared larvae will constitute a new product in terms of species, sizes and quality of ornamental fish on the aquarium market.  相似文献   
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Immobilised (killed) bovine spermatozoa were microinjected into bovine oocytes matured in vitro and cultured for six to nine days in vitro. A co-culture system with cumulus cells was used for the embryonic development. After one to two, three to four, five to six and seven to eight days the proportions of the oocytes which had developed to the two to four-cell, six to 12-cell, morula and blastocyst stages were 12.0 per cent (61 of 507), 9.3 per cent (47 of 507), 5.9 per cent (30 of 507) and 7.8 per cent (nine of 115), respectively. In contrast, none of the sham-operated group developed beyond the six-cell stage. This is the first report to show that bovine oocytes matured in vitro can undergo cleavage to the blastocyst stage after the injection of sperm in vitro. In addition, normal calves were obtained from the transfers of some of the embryos to recipient cows.  相似文献   
69.
The purpose of the present study is to investigate the feasibility of strain analysis using speckle tracking echocardiography (STE) in cats and to evaluate STE variables in cats with hypertrophic cardiomyopathy (HCM). Sixteen clinically healthy cats and 17 cats with HCM were used. Radial and circumferential strain and strain rate variables in healthy cats were measured using STE to assess the feasibility. Comparisons of global strain and strain variables between healthy cats and cats with HCM were performed. Segmental assessments of left ventricle (LV) wall for strain and strain rate variables in cats with HCM were also performed. As a result, technically adequate images were obtained in 97.6% of the segments for STE analysis. Sedation using buprenorphine and acepromazine did not affect any global strain nor strain rate variable. In LV segments of cats with HCM, reduced segmental radial strain and strain rate variables had significantly related with segmental LV hypertrophy. It is concluded that STE analysis using short axis images of LV appeared to be clinically feasible in cats, having the possibility to be useful for detecting myocardial dysfunctions in cats with diseased heart.  相似文献   
70.
The atomically smooth SrTiO(3) (100) with steps one unit cell in height was obtained by treating the crystal surface with a pH-controlled NH(4)F-HF solution. The homoepitaxy of SrTiO(3) film on the crystal surface proceeds in a perfect layer-by-layer mode as verified by reflection high-energy electron diffraction and atomic force microscopy. Ion scattering spectroscopy revealed that the TiO(2) atomic plane terminated the as-treated clean surface and that the terminating atomic layer could be tuned to the SrO atomic plane by homooepitaxial growth. This technology provides a well-defined substrate surface for atomically regulated epitaxial growth of such perovskite oxide films as YBa(2)Cu(3)O(7-delta).  相似文献   
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