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74.
CD39 activity correlates with stage and inhibits platelet reactivity in chronic lymphocytic leukemia
Dianne Pulte Kim E Olson M Johan Broekman Naziba Islam Harold S Ballard Richard R Furman Ashley E Olson Aaron J Marcus 《Journal of translational medicine》2007,5(1):23
Background
Chronic lymphocytic leukemia (CLL) is characterized by accumulation of mature appearing lymphocytes and is rarely complicated by thrombosis. One possible explanation for the paucity of thrombotic events in these patients may be the presence of the ecto-nucleotidase CD39/NTDPase-1 on the surface of the malignant cells in CLL. CD39 is the major promoter of platelet inhibition in vivo via its metabolism of ADP to AMP. We hypothesize that if CD39 is observed on CLL cells, then patients with CLL may be relatively protected against platelet aggregation and recruitment and that CD39 may have other effects on CLL, including modulation of the disease, via its metabolism of ATP. 相似文献75.
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77.
Cellular and developmental patterns of expression of Ret and glial cell line-derived neurotrophic factor receptor alpha mRNAs 总被引:6,自引:0,他引:6
C. A. Nosrat Andreas Tomac Barry J. Hoffer Lars Olson 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,115(3):410-422
Glial cell line-derived neurotrophic factor (GDNF) has recently been shown to signal by binding to GDNF receptor-alpha (GDNFR-α),
after which the GDNF-GDNFR-α associates with and activates the tyrosine kinase receptor Ret. We have localized Ret messenger
RNA (mRNA) in the developing and adult rodent and compared with to the expression of GDNF and GDNFR-α mRNA. Ret mRNA is strongly
expressed in dopamine neurons and α-motorneurons as well as in thalamus, ruber and occlumotor nuclei, the habenular complex,
septum, cerebellum, and brain stem nuclei. Ret mRNA was also found in several sensory systems, in ganglia, and in nonneuronal
tissues such as teeth and vibrissae. Very strong Ret mRNA signals are present in kidney and the gastrointestinal tract, where
Ret and GDNF mRNA expression patterns are precisely complementary. The presence of Ret protein was confirmed in adult dopamine
neurons using immunohistochemistry. GDNFR-α mRNA was strongly expressed in the developing and adult dopamine neurons. It was
also found in neurons in deep layers of cortex cerebri, in hippocampus, septum, the dentate gyrus, tectum, and the developing
spinal cord. In the kidney and the gastrointestinal tract, GDNFR-α mRNA and Ret mRNA distribution overlapped. Dorsal root
ganglia, cranial ganglia, and developing peripheral nerves were also positive. GDNFR-α was additionally found in sensory areas
and in developing teeth. Sensory areas included inner ear, eye, olfactory epithelium, and the vomeronasal organ, as well as
developing tongue papillae. The temporospatial pattern of expression of GDNFR-α mRNA did not always match that of Ret mRNA.
For instance, GDNFR-α mRNA was also found in the developing ventral striatum, including the olfactory tubercle, and in hippocampus.
These areas seemed devoid of Ret mRNA, suggesting that GDNFR-α might also have functions unrelated to Ret.
Received: 2 January 1997 / Accepted: 26 February 1997 相似文献
78.
Brilakis ES Olson LJ Berry GJ Daly RC Loisance D Zucker M Cooper LT 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2000,46(5):569-572
Giant cell myocarditis is a highly lethal disorder characterized by rapidly progressive congestive heart failure. The aim of this study was to describe the clinical course of patients with giant cell myocarditis who received a ventricular assist device. Patients with giant cell myocarditis were identified from the Multicenter Giant cell Myocarditis Registry. Bridging to cardiac transplantation in the giant cell myocarditis patients who received a ventricular assist device was compared with bridging in the general population of heart failure patients, as reported in the literature. Median posttransplantation survival for patients with giant cell myocarditis who received and did not receive ventricular assist devices was calculated by the Kaplan-Meier method and compared with use of the log-rank test. Nine patients with giant cell myocarditis who received ventricular assist devices were identified. Seven patients survived to transplantation, four were alive 30 days posttransplantation, and two survived to 1 year. The rate of successful bridging to transplantation in seven of nine patients (78%) is similar to that reported for other ventricular assist device recipients. Posttransplantation survival of 57% (4 of 7) at 30 days and 29% (2 of 7) at 1 year was significantly lower compared with 93% 1-year survival of the 30 patients with giant cell myocarditis who did not receive ventricular assist devices before transplantation (p<0.001). Ventricular assist devices can be an effective bridge to transplantation for patients with heart failure caused by giant cell myocarditis. Although their posttransplantation survival was poor in our series, a few patients had long-term survival. 相似文献
79.
C A Olson E W Cupp S Luckhart J M Ribeiro C Levy 《Journal of medical entomology》1992,29(6):1060-1062
Adults and immatures of Ixodes pacificus Cooley & Kohls were collected by flagging vegetation and from lizards during a 3-mo period in the Hualapai Mountain Park, Mohave County, AZ, in 1991. Collections were made at altitudes > or = 2,134 m. Two of 48 gut-salivary gland extracts of adult ticks were positive by IFA using a monoclonal antibody (H5332) specific to Borrelia burgdorferi. These are the first records of I. pacificus and of spirochetes tentatively identified as B. burgdorferi in Arizona. 相似文献
80.
The distribution of monomeric and polymeric actin in spermatozoa from the bull, boar, rabbit, human, rat, mouse, golden hamster, and guinea pig has been examined by using a monoclonal antiactin antibody and NBD-phallacidin. Actin was present in sperm from each species. When the monoclonal antibody was used, there was a species-specific distribution and intensity of fluorescence, but no generalized pattern. Specific fluorescence was noted in the neck and principal piece of human sperm; in the postacrosomal region, neck, and midpiece of bull and boar sperm; in the postacrosomal region, neck, and principal/equatorial segment border of rabbit sperm; in the neck region of hamster sperm; and in the neck, midpiece, and principal piece of rat, mouse, and guinea pig sperm. Sperm from all eight species displayed no specific fluorescence with NBD-phallacidin, indicating that actin was present in a nonfilamentous form. SDS extracts of sperm were analyzed by SDS-PAGE and Western blotting; in sperm from each species, a 42-kD protein with specific affinity for the monoclonal antibody was present. 相似文献