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11.
Differential regulation of basic protein phosphorylation by calcium phospholipid and cyclic-AMP-dependent protein kinases 总被引:2,自引:0,他引:2
Myelin basic protein, an 80-kilodalton (kDa) protein in rat oligodendrocytes, and an 80-kDa basic protein in neuroblastoma x neonatal Chinese hamster brain explant hybrids were phosphorylated extensively when the cells were treated with either phorbol esters (TPA) or diacylglycerols (e.g., oleyoyl-acetylglycerol). TPA-stimulated phosphorylation was inhibited by pre-incubation with 50 microM psychosine (galactosyl-sphingosine), confirming that it is mediated through the phospholipid-dependent protein kinase C (PK-C). Surprisingly, phosphorylation of these proteins was inhibited by incubation of cells with agents which result in activation of cyclic-AMP-dependent protein kinase (dibutyryl cyclic AMP or forskolin). In contrast, phosphorylation of other nonbasic proteins, for example, the oligodendrocyte-specific 2',3'-cyclic nucleotide phosphohydrolase, was stimulated under these conditions (Vartanian et al.: Proceedings of the National Academy of Sciences of the United States of America 85:939, 1988). The possible role of cyclic AMP in activating specific phosphatases or restricting the availability of diacylglycerol for PK-C activation is discussed. 相似文献
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Gaute W. Seljestad María Quintela Ellika Faust Kim T. Halvorsen Franois Besnier Eeva Jansson Geir Dahle Halvor Knutsen Carl Andr Arild Folkvord Kevin A. Glover 《Ecology and evolution》2020,10(12):6120-6135
Capture and long‐distance translocation of cleaner fish to control lice infestations on marine salmonid farms has the potential to influence wild populations via overexploitation in source regions, and introgression in recipient regions. Knowledge of population genetic structure is therefore required. We studied the genetic structure of ballan wrasse, a phenotypically diverse and extensively used cleaner fish, from 18 locations in Norway and Sweden, and from Galicia, Spain, using 82 SNP markers. We detected two very distinct genetic groups in Scandinavia, northwestern and southeastern. These groups were split by a stretch of sandy beaches in southwest Norway, representing a habitat discontinuity for this rocky shore associated benthic egg‐laying species. Wrasse from Galicia were highly differentiated from all Scandinavian locations, but more similar to northwestern than southeastern locations. Distinct genetic differences were observed between sympatric spotty and plain phenotypes in Galicia, but not in Scandinavia. The mechanisms underlying the geographic patterns between phenotypes are discussed, but not identified. We conclude that extensive aquaculture‐mediated translocation of ballan wrasse from Sweden and southern Norway to western and middle Norway has the potential to mix genetically distinct populations. These results question the sustainability of the current cleaner fish practice. 相似文献
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Exposure to interparental violence is associated with negative outcomes, such as depression, post-traumatic stress disorder and reduced cognitive abilities. However, little is known about the potential effects of witnessing domestic violence during childhood on gray matter volume (GMV) or cortical thickness. High-resolution 3.0 T volumetric scans (Siemens Trio Scanner) were obtained on 52 subjects (18–25 years) including 22 (6 males/16 females) with a history of visually witnessing episodes of domestic violence, and 30 (8 males/22 females) unexposed control subjects, with neither a current nor past DSM-IV Axis I or II disorder. Potential confounding effects of age, gender, level of parental verbal aggression, parental education, financial stress, full scale IQ, and total GMV, or average thickness were modeled using voxel based morphometry and FreeSurfer. Witnessing domestic violence subjects had a 6.1% GMV reduction in the right lingual gyrus (BA18) (P = 0.029, False Discovery Rate corrected peak level). Thickness in this region was also reduced, as was thickness in V2 bilaterally and left occipital pole. Theses regions were maximally sensitive to exposure to witnessing domestic violence between 11–13 years of age. Regional reductions in GMV and thickness were observed in both susceptible and resilient witnessing domestic violence subjects. Results in subjects witnessing domestic violence were similar to previously reported results in subjects with childhood sexual abuse, as the primary region affected was visual cortex. Brain regions that process and convey the adverse sensory input of the abuse may be specifically modified by this experience, particularly in subjects exposed to a single type of maltreatment. Exposure to multiple types of maltreatment is more commonly associated with morphological alterations in corticolimbic regions. These findings fit with preclinical studies showing that visual cortex is a highly plastic structure. 相似文献
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Of a consecutive series of 25 patients with peritonitis secondary to colonic diverticular disease all, except one with faecal peritonitis, underwent some form of emergency resection.All the three patients with faecal peritonitis died, but the 22 with purulent peritonitis survived. The average duration of the emergency admission of the 22 survivors was 25.4 days, and in nine (41%) of them intestinal continuity had been restored by the end of that admission.Thus some form of emergency resection is the operation of choice in patients with spreading peritonitis due to diverticular disease of the sigmoid colon. 相似文献