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41.
The release of immunoreactive (ir) dynorphin (DYN) and alpha-neoendorphin (ir-ANEO) from the isolated perfused rat duodenum was demonstrated using specific radioimmunoassays (RIAs). Depolarization of the tissue by increasing the potassium (K+) concentration up to 108 mM enhanced the release of ir-DYN and ir-ANEO in Ca2+-dependent manner. Administration of the serotonin-releasing agent fenfluramine (10(-6) M) and the serotonin receptor agonist m-chlorophenylpiperazine (m-CPP, 10(-6) M) stimulated the release of ir-DYN and ir-ANEO from the duodenum. A subsequent study revealed that serotonin (5-HT, 10(-6)-10(-4) M) induced a dose-dependent increase in the release of ir-DYN and ir-ANEO from the duodenum. The effect of 5-HT on the release of ir-DYN and ir-ANEO from the duodenum was antagonized by 5-HT antagonist cyproheptadine (10(-6) M). The presence of dynorphin and the related peptides in the gastrointestinal tract (GIT) and their release from the duodenum in vitro indicate that these peptides may act as transmitters involved in some GIT functions. Furthermore, our results suggest that at least part of 5-HT effects on the GIT may be mediated by the release of dynorphin and the related peptides. 相似文献
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Christina L. Nemeth David A. Gutman Waqas Majeed Shella D. Keilholz Gretchen N. Neigh 《PloS one》2014,9(5)
Microvascular disease leads to alterations of cerebral vasculature including the formation of microembolic (ME) strokes. Though ME are associated with changes in mood and the severity and progression of cognitive decline, the effect of ME strokes on cerebral microstructure and its relationship to behavioral endpoints is unknown. Here, we used adult and aged male rats to test the hypotheses that ME lesions result in subtle changes to white and gray matter integrity as detected by high-throughput diffusion tensor imaging (DTI) and that these structural disruptions correspond to behavioral deficits. Two weeks post-surgery, aged animals showed depressive-like behaviors in the sucrose consumption test in the absence of altered cerebral diffusivity as assessed by ex-vivo DTI. Furthermore, DTI indices did not correlate with the degree of behavioral disruption in aged animals or in a subset of animals with observed tissue cavitation and subtle DTI alterations. Together, data suggest that behavioral deficits are not the result of damage to brain regions or white matter tracts, rather the activity of other systems may underlie functional disruption and recovery. 相似文献
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A. Majeed 《BMJ (Clinical research ed.)》1996,313(7068):1274-1275
48.
Majeed R. A. Al-Hilli Barry G. Warner Taro Asada Ali Douabul 《Wetlands Ecology and Management》2009,17(3):207-223
A vast ecosystem of wetlands and lakes once covered the Mesopotamian Plain of southern Iraq. Widespread drainage in the 1990s
nearly obliterated both components of the landscape. This paper reports the results of a study undertaken in 1972–1975 on
the vegetation of the wetlands prior to drainage and provides a unique baseline for gauging future restoration of the wetland
ecosystems in Mesopotamia. Five representative study sites were used to assess the flora, three of which were wetlands. A
total of 371 plant species were recorded in the five sites, of which approximately 40% represent obligate or facultative wetland
species. The wetland vegetation was classified into five major physiognomic forms (submerged, floating, herbaceous tall emergent,
herbaceous low emergent and woody low emergent), which was further subdivided into 24 fresh and halophytic communities. Water
levels greatly fluctuated across the different types of wetlands, and mean surface water depth ranged from below to greater
than 2 m above the sediment surface, reflecting permanently, seasonally or intermittently wet habitats. Aboveground biomass
was also highly variable among the communities. The Phragmites australis community, which was the most extensive community type, had the greatest biomass with an average value of approximately 5,000 g m−2 in summer. Distribution and community composition were largely controlled by water levels and saline-freshwater gradients.
Canonical correspondence analysis showed that salinity and water depth were the most important factors to explain species
distribution. Environmental variables related to soil salinity separated halophytic species in woody low emergent and herbaceous
low emergent forms (Tamarix galica, Cressa cretica, Alhagi mannifera, Aeluropus lagopoides, Juncus rigida, and Suaeda vermiculata) from other species. Their habitats were also the driest, and soil organic matter content was lower than those of other species.
Habitats with deepest water were dominated by submerged aquatic and floating leaved species such as Nymphoides peltata, Ceratophyllum demersum, and Najas armata. Such diverse environmental conditions in the Mesopotamian wetland would be greatly affected by evapotranspiration, river
water inputs from north, ground water inputs, local soil conditions, and a tide or seiche-controlled northward transgression
of water from the Gulf. These environmental conditions should be considered in restoration plans if plant communities existed
in the mid-1970s are to be part of the desired restoration goals.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Faeza Abdul Kareem Almashal Al-Hujaj Hamsa Hussein Jassem Ahmed Majeed Al-Masoudi Najim Aboud 《Russian Journal of Bioorganic Chemistry》2020,46(3):360-370
Russian Journal of Bioorganic Chemistry - A new series of 1,4-disubstituted-1,2,3-triazolethymine derivatives (VIa–e) were synthesized and characterized by spectroscopic studies. The in vitro... 相似文献