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91.
In a survey that was conducted during the year 2011, a local strain of Aphid lethal paralysis virus (ALPV) was identified and isolated from a wild population of Aphis nerii aphids living on Nerium oleander plants located in northern Israel. The new strain was tentatively named (ALPV-An). RNA extracted from the viral particles allowed the amplification and determination of the complete genome sequence. The virus genome is comprised of 9835 nucleotides. In a BLAST search analysis, the ALPV-An sequence showed 89 % nucleotide sequence identity with the whole genome of a South African ALPV and 96 and 94 % amino acid sequence identity with the ORF1 and ORF2 of that strain, respectively. In preliminary experiments, spray-applied, purified ALPV virions were highly pathogenic to the green peach aphid Myzus persicae; 95 % mortality was recorded 4 days post-infection. These preliminary results demonstrate the potential of ALPV for use as a biologic agent for some aphid control. Surprisingly, no visible ALPV pathogenic effects, such as morphological changes or paralysis, were observed in the A. nerii aphids infected with ALPV-An. The absence of clear ALPV symptoms in A. nerii led to the formulation of two hypotheses, which were partially examined in this study. The first hypothesis suggest that A. nerii is resistant or tolerant of ALPV, while the second hypothesis propose that ALPV-An may be a mild strain of ALPV. Currently, our results is in favor with the first hypothesis since ALPV-An is cryptic in A. nerii aphids and can be lethal for M. persicae aphids. 相似文献
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Comparison of myelopoiesis in continuous human bone marrow and cord blood cultures was performed. The presence of major histocompatibility complex (MHC) antigens on myeloid precursors (CFU-GM) from cord blood was confirmed using monoclonal antibodies (MoAb) defining class I (i.e., anti-beta 2-microglobulin (B2, MG1) anti-HLA-A,B heavy chain (W6/32), and anti-HLA locus B(4E), and class II (HLA-DR (7,2] antigens. The effect of long-term culture on the expression of these antigens was investigated. Our studies indicate that following prolonged in vitro culture there is a decrease in the expression of MHC antigens on CFU-GM. Our observations provide a rationale for considering the use of cord blood leukocytes subjected to long-term culture as an alternative to allogeneic hematopoietic cell transplantation. 相似文献
96.
Molecular clones of the integrated form of the genome of equine infectious anemia virus (EIAV), the etiologic agent of a naturally occurring, worldwide disease of horses, were obtained. The restriction map of a full-length genome was determined. Additional evidence for the close evolutionary relationship between EIAV and a prototype lentivirus (caprine arthritis encephalitis virus) was acquired by Southern blotting and immunological analyses. An interspecies radioimmunoassay was developed in which EIAV and ovine and caprine lentiviruses could be detected equally well. These studies make available precisely defined reagents to pursue the study of the mechanisms of pathogenesis of lentiviral induced diseases. 相似文献
97.
Further aspects of design for distal extension removable partial dentures based on the Kennedy classification 总被引:3,自引:0,他引:3
A supplement to the Kennedy classification of partially edentulous arches for restoration with removable partial dentures has been suggested. Factors affecting denture design relating to the position of the abutment teeth, the symmetry of the edentulous distal extensions, the arch form and the cross-sectional shape of the residual ridges have been discussed and classified. An understanding of the movement of the denture bases in relation to the influence of these factors makes for a rational approach to removable partial denture design and the treatment of complications observed clinically in removable partial denture wearers. 相似文献
98.
Nadav Kimelman‐Bleich Dror Seliktar Ilan Kallai Gregory A. Helm Zulma Gazit Dan Gazit Gadi Pelled 《Journal of tissue engineering and regenerative medicine》2011,5(5):384-393
Mechanical loading has been described as a highly important stimulus for improvements in the quality and strength of bone. It has also been shown that mechanical stimuli can induce the differentiation of mesenchymal stem cells (MSCs) along the osteogenic lineage. We have previously demonstrated the potent osteogenic effect of MSCs engineered to overexpress the BMP2 gene. In this study we investigated the effect of mechanical loading on BMP2‐expressing MSC‐like cells, using a special bioreactor designed to apply dynamic forces on cell‐seeded hydrogels. Cell viability, alkaline phosphatase (ALP) activity, BMP2 secretion and mineralized substance formation in the hydrogels were quantified. We found that cell metabolism increased as high as 6.8‐fold, ALP activity by 12.5‐fold, BMP2 secretion by 182‐fold and mineralized tissue formation by 1.72‐fold in hydrogels containing MSC‐like cells expressing BMP2, which were cultured in the presence of mechanical loading. We have shown that ex vivo mechanical loading had an additive effect on BMP2‐induced osteogenesis in genetically engineered MSC‐like cells. These data could be valuable for bone tissue‐engineering strategies of the future. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
99.
Molecular targets for tendon neoformation 总被引:2,自引:1,他引:2
Aslan H Kimelman-Bleich N Pelled G Gazit D 《The Journal of clinical investigation》2008,118(2):439-444
Tendons and ligaments are unique forms of connective tissue that are considered an integral part of the musculoskeletal system. The ultimate function of tendon is to connect muscles to bones and to conduct the forces generated by muscle contraction into movements of the joints, whereas ligaments connect bone to bone and provide joint stabilization. Unfortunately, the almost acellular and collagen I-rich structure of tendons and ligaments makes them very poorly regenerating tissues. Injured tendons and ligaments are considered a major clinical challenge in orthopedic and sports medicine. This Review discusses the several factors that might serve as molecular targets that upon activation can enhance or lead to tendon neoformation. 相似文献
100.
Grace J. Yoo Ellen G. Levine Caryn Aviv Cheryl Ewing Alfred Au 《Supportive care in cancer》2010,18(12):1521-1530