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61.
Terry Crow Juan-Juan Xue-Bian Vilma Siddiqi Joseph T. Neary† 《Journal of neurochemistry》2001,78(2):358-364
The mitogen‐activated protein kinase (MAPK) cascade is an important contributor to synaptic plasticity and learning in both vertebrates and invertebrates. In the nudibranch mollusk Hermissenda, phosphorylation and activation of the extracellular signal‐regulated protein kinase (ERK), a key member of a MAPK cascade, is produced by one‐trial and multitrial Pavlovian conditioning. Several signal transduction pathways that are activated by 5‐hydroxytryptamine (5‐HT) and may contribute to conditioning have been identified in type B photoreceptors. However, the regulation of ERK activity by ‘upstream’ signaling molecules has not been previously investigated in Hermissenda. In the present study we examined the role of protein kinase C (PKC) in the serotonin (5‐HT) activation of the ERK pathway. The phorbol ester TPA produced an increase in ERK phosphorylation that was blocked by the PKC inhibitors GF109203X or Gö6976. TPA‐dependent ERK phosphorylation was also blocked by the MEK1 inhibitors PD098059 or U0126. The increased phosphorylation of ERK by 5‐HT was reduced but not blocked by pretreatment with the calcium chelator BAPTA‐AM or pretreatment with Gö6976 or GF109203X. These results indicate that Ca2+‐dependent PKC activation contributes to ERK phosphorylation, although a PKC‐independent pathway is also involved in 5‐HT‐dependent ERK phosphorylation and activation. 相似文献
62.
Belonolaimus longicaudatus is a serious problem on bermudagrass, a common warm-season turfgrass, in Florida. The cancellation of organophosphate nematicides necessitates that new management tools be identified for use on sports turf. Postplant application of 1,3-dichloropropene (1,3-D) on bermudagrass was evaluated for management of B. longicaudatus on golf course fairways and driving ranges. A series of 10 experiments were conducted to evaluate the effectiveness of 1,3-D in reducing population densities of B. longicaudatus and enhancing bermudagrass recovery from nematode damage. In 5 of 10 experiments, 1,3-D injected at 46.8 liters/ha was effective in reducing population densities of B. longicaudatus (P < 0.05) compared to untreated plots 2 to 4 weeks after treatment. One month after treatment, population densities of B. longicaudatus ranged from 59% to 97% of those in untreated plots. Nematode suppression generally lasted 2 months or less. Turf visual performance was improved following injection with 1,3-D (P < 0.05) over untreated plots when other factors were not limiting. Turf root development also was enhanced following injection with 1,3-D. Postplant injection of 1,3-D could be a useful nematode management tool for certain sports turf applications. 相似文献
63.
L F Marek J Mudge L Darnielle D Grant N Hanson M Paz Y Huihuang R Denny K Larson D Foster-Hartnett A Cooper D Danesh D Larsen T Schmidt R Staggs J A Crow E Retzel N D Young R C Shoemaker 《Génome》2001,44(4):572-581
We are building a framework physical infrastructure across the soybean genome by using SSR (simple sequence repeat) and RFLP (restriction fragment length polymorphism) markers to identify BACs (bacterial artificial chromosomes) from two soybean BAC libraries. The libraries were prepared from two genotypes, each digested with a different restriction enzyme. The BACs identified by each marker were grouped into contigs. We have obtained BAC- end sequence from BACs within each contig. The sequences were analyzed by the University of Minnesota Center for Computational Genomics and Bioinformatics using BLAST algorithms to search nucleotide and protein databases. The SSR-identified BACs had a higher percentage of significant BLAST hits than did the RFLP-identified BACs. This difference was due to a higher percentage of hits to repetitive-type sequences for the SSR-identified BACs that was offset in part, however, by a somewhat larger proportion of RFLP-identified significant hits with similarity to experimentally defined genes and soybean ESTs (expressed sequence tags). These genes represented a wide range of metabolic functions. In these analyses, only repetitive sequences from SSR-identified contigs appeared to be clustered. The BAC-end sequences also allowed us to identify microsynteny between soybean and the model plants Arabidopsis thaliana and Medicago truncatula. This map-based approach to genome sampling provides a means of assaying soybean genome structure and organization. 相似文献
64.
Mary K Crow 《Arthritis research & therapy》2009,11(5):245-11
Advances in genetics and new understanding of the molecular pathways that mediate innate and adaptive immune system activation,
along with renewed focus on the role of the complement system as a mediator of inflammation, have stimulated elaboration of
a scheme that might explain key mechanisms in the pathogenesis of systemic lupus erythematosus. Clinical observations identifying
important comorbidities in patients with lupus have been a recent focus of research linking immune mechanisms with clinical
manifestations of disease. While these advances have identified rational and promising targets for therapy, so far the therapeutic
trials of new biologic agents have not met their potential. Nonetheless, progress in understanding the underlying immunopathogenesis
of lupus and its impact on clinical disease has accelerated the pace of clinical research to improve the outcomes of patients
with systemic lupus erythematosus. 相似文献
65.
OBJECTIVE--To investigate the social adjustment in childhood of people who as adults have psychiatric disorders. DESIGN--Subjects in a prospectively followed up cohort (the national child development study) who had been admitted as adults to psychiatric hospitals were compared with the rest of the cohort on ratings of social behaviour made by teachers at the ages of 7 and 11 years. SUBJECTS--40 adult patients with schizophrenic illnesses, 35 with affective psychoses, and 79 with neurotic illness who had been admitted for psychiatric reasons by the age of 28. 1914 randomly selected members of the cohort who had never been admitted for psychiatric treatment. MAIN OUTCOME MEASURES--Overall scores and scores for overreaction (externalising behaviour) and underreaction (internalising behaviour) with the Bristol social adjustment guide at ages 7 and 11. RESULTS--At the age of 7 children who developed schizophrenia were rated by their teachers as manifesting more social maladjustment than controls (overall score 4.3 (SD 2.4) v 3.1 (2.0); P < 0.01). This was more apparent in the boys (5 (2.6)) than the girls (3.4 (1.8)) and related to overreactive rather than underreactive behaviour. At both ages prepsychotic (affective) children differed little from normal controls. By the age of 11 preneurotic children, particularly the girls, had an increased rating of maladjustment (including overreactions and underreactions). CONCLUSION--Abnormalities of social adjustment are detectable in childhood in some people who develop psychotic illness. Sex and the rate of development of different components of the capacity for social interaction are important determinants of the risk of psychosis and other psychiatric disorders in adulthood. 相似文献
66.
67.
D O Kasprisin M Crow C McClintock J Lawson 《American journal of physical anthropology》1987,73(1):1-7
Large numbers of Indians from Oklahoma were screened for a variety of red cell antigens. Sufficient numbers of Cherokees, Creeks, and Choctaws were studied to calculate gene frequencies. These tribes originated in the Southeastern United States and were forcibly moved to Oklahoma. The Creeks and Choctaws have not been studied previously. A small number of Cherokees remained in North Carolina, and their blood types have been reported. The blood types of the Oklahoma Cherokees are quite similar to those observed there but one important difference was discovered. The data previously reported concerning the Eastern Cherokees revealed the absence of the Dia antigen. The present study found that the Oklahoma Cherokees do have the Dia antigen, although in a lower percentage than the other southeastern tribes. The Creeks and Choctaws share a linguistic heritage as well as having similar red cell phenotypes. 相似文献
68.
69.
70.
R. S. Crow 《BMJ (Clinical research ed.)》1960,2(5194):271-273