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71.
The effects of neonatal 6-hydroxydopamine (6-OH-DA) treatment (systemic administration) on norasrenaline (NA) metabolism, trun over, and receptor charasteristics have been investigated in rat brain in the adult atage. This treatment is known to preferentially affect the locus coeruleus (LC) NA system leading to a marked NA denervation in the cerebral cortex and a hyperinnervation of NA nerve terminals in the pons and medulla oblongata without influencing the LC perikarya. The main NA metabolite, 3-methoxy-4-hydroxyphenylglycol (MOPEG) was reduced by about 70% in the cerebral cortex after 6-OH-DA-treatment at birth while the endogenous NA was almost completely depleted (-92%). The MOPEG levels were not significantly changed in the pons medulla after 6-OH-DA treatment in contrast to the 60% increase of the endogenous NA concentration. The relative reduction of NA in the cerebral cortex of 6-OH-Da treated rats increased in the cerebral cortex is increased after 6-OH-DA, while decreased in the pons-medulla, possibly related to changes in the activation of presynaptic α-adrenoreceptors in both regions. NA-induced formation of cAMP in vitro was found to be markedly increased in the cerebral cortex after 6-OH-DA, whereas no consistent change was observed in the pons medulla. Measurements of α- and β-receptor binding in vitro using radioligand techniques showed an increase of binding sites (20%–50%) for both receptors in the neocortex after 6-OH-DA, whereas no changes were observed in the pons medulla. The 6-OH-Da induced changes in NA turnover, cAMP generating systems, and receptor density may all represent compensatory processes following the altered development of the NA neurons induced by 6-OH-DA. 相似文献
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Jun Ying Mohammad H. Rahbar D. Michael Hallman Ladia M. Hernandez Margret R. Spitz Michele R. Forman Olga Y. Gorlova 《PloS one》2013,8(2)
Evidence from human and animal research indicates that choline metabolic pathways may be activated during a variety of diseases, including cancer. We report results of a case-control study of 2821 lung cancer cases and 2923 controls that assessed associations of choline and betaine dietary intakes with lung cancer. Using multivariable logistic regression analyses, we report a significant association between higher betaine intake and lower lung cancer risk that varied by smoking status. Specifically, no significant association was observed between betaine intake and lung cancer among never-smokers. However, higher betaine intake was significantly associated with reduced lung cancer risk among smokers, and the protective effect was more evident among current than former smokers: for former and current smokers, the ORs (95% CI) of lung cancer for individuals with highest as compared to lowest quartiles of intake were 0.70(0.55–0.88) and 0.51(0.39–0.66) respectively. Significant linear trend of higher betaine intake and lower lung cancer risk was observed among both former (ptrend = 0.002) and current (ptrend<0.0001) smokers. A similar protective effect was also observed with choline intake both in overall analysis as well as among current smokers, with p-values for chi-square tests being 0.001 and 0.004 respectively, but the effect was less evident, as no linear trend was observed. Our results suggest that choline and betaine intake, especially higher betaine intake, may be protective against lung cancer through mitigating the adverse effect of smoking. 相似文献
74.
Hallman DM Olsson EM von Schéele B Melin L Lyskov E 《Applied psychophysiology and biofeedback》2011,36(2):71-80
Recent studies focusing on autonomic nervous system (ANS) dysfunctions, together with theoretical pathophysiological models
of musculoskeletal disorders, indicate the involvement of ANS regulation in development and maintenance of chronic muscle
pain. Research has demonstrated the effectiveness of heart rate variability (HRV) biofeedback (BF) in increasing HRV and reducing
the symptoms of different disorders characterized by ANS aberration. The study investigated the effects of resonance frequency
HRV BF on autonomic regulation and perceived health, pain, stress and disability in 24 subjects with stress-related chronic
neck-shoulder pain. Twelve subjects participated in 10 weekly sessions of resonant HRV BF and were compared to a control group.
Subjective reports and HRV measures during relaxation and in response to a standardized stress protocol were assessed for
both groups pre- and post-intervention. Group × time interactions revealed a significantly stronger increase over time in
perceived health (SF-36) for the treatment group, including vitality, bodily pain and social functioning. Interactions were
also seen for HRV during relaxation and reactivity to stress. The present pilot study indicates improvement in perceived health
over a 10 week intervention with HRV-biofeedback in subjects with chronic neck-pain. Increased resting HRV as well as enhanced
reactivity to hand grip and cold pressor tests might reflect beneficial effects on ANS regulation, and suggest that this intervention
protocol is suitable for a larger controlled trial. 相似文献
75.
Bactrocera invadens Drew, Tsuruta & White (Diptera: Tephritidae) is spreading throughout central Africa attacking a variety of fruit; quarantines are placed on fruit from this region that are considered hosts. The only phytosanitary treatment that is commercially available is an ionizing irradiation treatment for all Tephritidae at 150 Gy. The development of other treatments, such as heat, cold, or fumigation, usually requires testing tens of thousands of insects at a dose that provides efficacy and may take several years. It may be possible to shorten the time required to develop treatments by comparing tolerance of a new quarantine pest to tolerances of pests with similar behaviors and modes of infestation for which treatment schedules are available. Cold and heat tolerance ofB. invadens was compared with tolerance of Anastrepha ludens (Loew), Bactrocera dorsalis (Hendel), and Ceratitis capitata (Wiedemann) in vitro. Third-instar B. invadens was no more cold tolerant than the other species when treated in diet at 0.94 +/- 0.65 degrees C and no more heat tolerant than C. capitata when immersed in vials in water at 44.7 +/- 0.1 degrees C. The data at 0.94 +/- 0.65 degrees C was used to include B. invadens in a USDA cold treatment schedule for citrus fruit from Africa so that trade would not be interrupted while protecting U.S. agriculture from this invasive pest. 相似文献
76.
Jönsson C Hallman K Andersson H Stemme G Malkoch M Malmström E Hult A Moberg C 《Bioorganic & medicinal chemistry letters》2002,12(14):1857-1861
Metal complexes of chiral oxazoline derivatives immobilized on soluble as well as insoluble supports serve as versatile asymmetric catalysts in a variety of applications. In a few cases recovery and reuse of the chiral ligands have been achieved. 相似文献
77.
Surfactant lipids in the alveolar space are believed to play an important role in normal respiratory function. Although the surface-active phospholipids have been extensively studied, the possible role of glycolipids in the surfactant remains to be explored. We have studied the glycolipid composition of cell-free bronchoalveolar lavage from healthy subjects and from adult patients with respiratory distress syndrome. Glycolipids were barely detectable in bronchoalveolar lavage from healthy subjects. However, in adult respiratory distress syndrome, the amount of glycolipid relative to phospholipid was increased by more than twenty times. These lipids, identified as lactosylceramide (galactose-glucose-ceramide) and paragloboside (galactose-N-acetylglucosamine-galactose-glucose-ceramide), may prove to be sensitive markers of lung injury. Since the glycolipids decreased the surface activity of surfactant in vitro, their potential role in the pathogenesis of adult respiratory distress syndrome should be considered. 相似文献
78.
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80.
Lamellar bodies and alveolar lavage from adult mammalian lung contain unusually high concentrations of phosphatidylglycerol that could serve as a sensitive indicator of surfactant. Phosphatidylglycerol was absent and phosphatidylinositol was correspondingly prominent in surfactant from the preterm rabbit fetus. Phosphatidylglycerol rapidly appeared and phosphatidylinositol decreased following the delivery. Surfactant isolated from the prematurely born rabbit or from humans with respiratory distress syndrome never contained phosphatidylglycerol. Comparison between lamellar bodies from fetal and postnatal rabbits revealed remarkably similar composition except for the acidic phospholipids; however, the physico-chemical properties were different. The compressibility of the surface film (i.e. the ratio of the fractional decrease in surface area and the corresponding decrease in surface tension) at low surface tensions was higher with fetal than with postnatal surfactant, whereas the difference in minimum surface tensions was small. These data suggest that phosphatidylglycerol is not an essential component required for the formation of the complex, but it improves the properties of surfactant in stabilizing the alveoli. 相似文献