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991.
992.
Nadine Douziech Ildikò Seres Anis Larbi Edit Szikszay Pierre Michel Roy Marcel Arcand Gilles Dupuis Tamàs Fulop 《Experimental gerontology》2002,37(2-3):369-387
Previously, we have demonstrated age-associated alterations in transmembrane signaling. One of the most reproducible alterations found in the immune response with aging is the decrease of lymphocyte proliferation on stimulation with various different mitogens. Here, we confirm that proliferative responses to stimulation with phytohaemagglutin (PHA), recombinant human IL-2, or anti-CD3 monoclonal antibody are all greater in the young (20-25 years) than old (60-87 years) population. We attempted to modulate the proliferative response using various agents acting at different levels of transmembrane signaling (pertussis toxin, cholera toxin, isoproterenol, PMA, Ca ionophore A23187), as well as at the level of the lymphocyte plasma membrane (methyl-beta-cyclodextrin, MBCD), or by using antioxidant vitamins (Vitamin E or C). None of these agents was able to restore effectively the proliferative response of lymphocytes from the aged to the level of young subjects. Even the combination of A23187 and PMA acting directly on calcium metabolism and protein kinase C activity was insufficient to restore the decreased mitogenic capacity of T cells from elderly subjects. Cyclodextrin, which decreases the cholesterol content of the membrane, increased the proliferative response of lymphocytes of elderly subjects, but not to the level of the young. Vitamin E had a very strong inhibitory effect on lymphocyte stimulation in both the age groups, except in combination with MBCD in T cells of the elderly, while Vitamin C had no significant modulatory effect. MAPK ERK and p38 activation was found to be decreased with aging in T cells after anti-CD3 mAb stimulation. Vitamin E but not Vitamin C strongly inhibited MAPK ERK or p38 activation. The direct activation of certain molecules or the modulation of the cholesterol content of the membrane seems to be effective immunomodulatory interventions with aging. 相似文献
993.
Insulin-like growth factor-I receptors in human brain and pituitary gland: An autoradiographic study
Jacques De Keyser Nadine Wilczak Jean-Paul De Backer Luc Herroelen G. Vauquelin 《Synapse (New York, N.Y.)》1994,17(3):196-202
Insulin-like growth factor (IGF)-I receptors were studied in adult human postmortem brain and pituitary gland using quantitative autoradiography with human recombinant [125I]IGF-I. The highest densities were found in the choroid plexus, pituitary gland-where IGF-I receptors were mainly concentrated in the anterior lobe, pineal gland, glomerular layer of the olfactory bulb, and the molecular layer of the cerebellar cortex. Moderate densities were present in cerebral cortex, caudate nucleus, putamen, accumbens, the CA1, CA2, CA3 fields and dentate gyrus of the hippocampus, the dendate nucleus of the cerebellum, amygdala, thalamus, pontine nuclei, and substantia nigra. All other brain areas, including white matter, contained low densities of IGF-I receptors. The finding that several well-defined brain structures are enriched with IGF-I receptors suggests a rieurotrophic/survival or neuromodulatory role of insulin-like growth factors on specific neuronal systems. IGF-I receptors observed in the white matter may be associated with oligodendrocytes. © 1994 Wiley-Liss, Inc. 相似文献
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996.
Carlos Portugal-Nunes Teresa Costa Castanho Liliana Amorim Pedro Silva Moreira Jos Mariz Fernanda Marques Nuno Sousa Nadine Correia Santos Joana Almeida Palha 《Nutrients》2020,12(11)
Several conditions are risk factors for iron deficiency (ID), some of which are highly prevalent in older individuals. Despite the amount of evidence pointing for a role of ID in cognition, mood and physical functional ability, the research addressing these associations in older individuals is still scarce. In the present study, 162 older community-dwelling individuals (29.53% classified as ID) were enrolled in a cross-sectional analysis and characterized regarding cognition, mood, functional ability, general nutritional intake and iron status. Assessment of iron status was performed using several blood biomarkers. Storage and erythropoiesis dimensions were positively associated with memory, along with an interaction (moderator effect) between iron storage and nutritional status. A more depressed mood was negatively associated with (iron) transport, transport saturation and erythropoiesis dimensions, and functional tiredness was positively associated with the erythropoiesis dimension. These observations indicate that lower iron status is associated with depressive mood, functional tiredness and poorer memory ability, with the latter moderated by nutritional status. These findings suggest that using iron as a continuous variable may be useful in finding associations with iron homeostasis, eventually missed when iron levels are considered within the usual classification groups. 相似文献
997.
Freiberg Alice Horvath Katy Hahne Taurai Monalisa Drössler Stephanie Kämpf Daniel Spura Anke Buhs Bernhard Reibling Nadine De Bock Freia Apfelbacher Christian Seidler Andreas 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2021,64(12):1592-1602
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Zur Prävention tröpfchenübertragener Infektionskrankheiten wird das Tragen einer Maske im öffentlichen Raum... 相似文献
998.
Myriam Abboud Rana Rizk Fatme AlAnouti Dimitrios Papandreou Suzan Haidar Nadine Mahboub 《Nutrients》2021,13(1)
Evidence of synergic health effects of co-supplementation with vitamin D and probiotics is emerging. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses PRISMA statement, scientific databases and the grey literature were searched, and a narrative review and risk of bias assessment were conducted. Seven randomized controlled trials were included, which had low risk of bias. Six studies were double-blind, and once single-blind, extended over 6–12 weeks, and included 50–105 participants. Conditions explored included schizophrenia, gestational diabetes, type 2 diabetes and coronary heart disease, polycystic ovarian syndrome, osteopenia, irritable bowel syndrome (IBS), and infantile colic. Supplementation frequency was daily or bi-monthly, with mainly vitamin D3, and Lactobacillus, Bifidobacterium, and Streptococcus. Comparators were placebo, vitamin D, lower vitamin D dose, and probiotics and lower vitamin D dose. The co-supplementation yielded greater health benefits than its comparators did in all studies except in one assessing IBS. Beneficial effects included decreased disease severity, improved mental health, metabolic parameters, mainly insulin sensitivity, dyslipidemia, inflammation, and antioxidative capacity, and lower use of healthcare. Co-supplementation of vitamin D and probiotics generated greater health benefits than its comparators did. More studies in other diseases and various populations are needed to confirm these findings and to elucidate the optimal form, composition, and frequency of this co-supplementation. 相似文献
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1000.
Jan-Carlo?JanssenEmail authorView authors OrcID profile Sebastian?Mei?ner Nadine?Woythal Vikas?Prasad Winfried?Brenner Gerd?Diederichs Bernd?Hamm Marcus?R.?Makowski 《European radiology》2018,28(2):610-619