No description available.

This study aimed to investigate the effects of commercially available natural (sugar cane molasses, white sugar and brown sugar) and artificial (Canderel™, Equal™, Natreen™, Sweetex™, Splenda™ and Swheet™) sweeteners on various physiological systems. The artificial sweeteners tested in this study may be categorised into their respective groups based on their primary ingredient. The brands Canderel™ and Equal™ contain aspartame, Natreen™ and Sweetex™ consist of saccharin and Splenda™ and Swheet™ are composed of sucralose. The inclusion of artificial or natural sweeteners in the human diet has been continually debated and their implication in the development of certain diseases has raised concern regarding their safe use. Therefore, it is necessary that these food products be subjected to a battery of tests to determine adverse effects on human health.

ABSTRACT With aging, changes in the immune system, makes cognitive performance, and the prevalence of stressors can lead to poorer overall functioning. Within the immune system, a balance should exist between cytokines regulating Th1 and Th2 immune responses; however, age-related declines in the endocrine and immune systems can disrupt this equilibrium. Several studies report higher levels of Th1 associated cytokines in inflammatory conditions of the brain, whereas fewer studies remark on Th2 associated cytokines and cognitive functioning. Declining cognitive abilities are a common concern that accompanies advancing age and some research has suggested the prevalence and impact of stressors lead to poorer performance. Participants included 92 older adults (M = 74.05 years) who completed tests of cognitive performance and stress measures, and 41 persons who had valid data on Th1 and Th2 cytokines. The results indicated that increasing age is significantly associated with several cognitive domains including executive functioning, speed of processing, and episodic memory. As hypothesized, moderation analysis revealed the relationship between Th1 and Th2 cytokinic profiles, as denoted by the IFN-γ/IL-4 ratio, is a significant moderator between stress and cognitive performance. Specifically, immune profiles skewed towards Th1 predict a significant amount of variation between high stress scores and low cognitive performance, whereas this was not found for immune profiles skewed towards Th2. Overall, the current study suggests that a pro-inflammatory state permits stress to exert a negative influence on cognitive performance.

Eine Vielzahl präklinischer Schlaganfallstudien zeigte die neuroprotektive und neuroregenerative Wirkung des hämatopoetischen Wachstumsfaktors G-CSF (Granulozyten-Kolonie stimulierender Faktor). Ein Wirkungsmechanismus des G-CSF ist die Mobilisation von protektiven Knochen-markzellen in die ischämische Läsion, wobei diese zeitverzögert nach G-CSF-Gabe stattfindet. Eine zusätzliche frühzeitige Transplantation mononukleärer Knochenmarkzellen (BM MNC) könnte diese therapeutische Lücke füllen. Ziel der vorliegenden Studie war es, die Wirksamkeit dieser Kombinations-therapie in einem Schlaganfallmodell der spontan hypertensiven Ratte (SHR) zu testen. Syngene BM MNC wurden aus dem Knochenmark von SHRs durch immunmagnetische Depletion der Granulozyten isoliert. Nach Verschluss der Arteria cerebri media wurde den Tieren über insgesamt 5 Tage G-CSF verabreicht und zusätzlich zu einem frühen (6h nach Schlaganfall) oder späteren (48h nach Schlaganfall) Zeitpunkt BM MNC intravenös appliziert. Unbehandelte Schlaganfalltiere sowie Tiere mit alleiniger G-CSF-Therapie dienten als Kontrolle. Das Infarktvolumen wurde weder durch die alleinige G-CSF-Gabe noch durch die zusätzliche Zelltherapie verändert. Dennoch wiesen Tiere mit G-CSF-Einzeltherapie eine anhaltende funktionelle Verbesserung des sensomotorischen Defizites auf. Während die zusätzliche frühzeitige Zelltransplantation (6h) keinen weiteren Therapieeffekt zeigte, führte die Zelltransplantation nach 48h zu einer Aufhebung des protektiven G-CSF Effektes. Die G-CSF-Therapie bewirkte erwartungsgemäß einen deutlichen Anstieg der zirkulierenden Leukozyten. Interessanterweise wurde der Granulozytengehalt im Blut und in der Milz durch die einmalige Zelltherapie nach 48h signifikant erhöht. Ein Großteil der transplantierten BM MNC (48h) konnte in der Milz nachgewiesen werden und führte dort vermutlich zu einer kompetitiven Hemmung des Granulozytenabbaus. Dies hatte sowohl den Anstieg der zirkulierenden Granulozyten als auch deren vermehrte Infiltration in das ischämische Hirngewebe zur Folge und könnte schließlich den negativen Einfluss auf die funktionelle Verbesserung erklären. Die beobachteten Interaktionsmechanismen werfen ein interessantes Licht auf die mögliche Wirkungsweise von Zelltherapien und unterstreichen die entscheidende Rolle des Immunsystems in der Pathophysiologie des Schlaganfalls.

Melatonin – is a hormone produced by the pineal gland during the dark time. Light during the night suppresses melatonin production. Melatonin is an important biological body regulator: it controls daily and seasonal biorhythms, glucose metabolism, gonadal activity, cardiovascular system, gastrointestinal tract and the activity of the immune system There is a lot of scientific information about the immunoregulative properties of melatonin. Melatonin modulates the development of some organs of the immune system, cell differentiation, immune response and cytokine production. The imunomodulatory activity of melatonin is usually determined by the following experimental models: surgical pinealectomy, in vivo treatment with melatonin or in vitro treatment of the immune cells with melatonin. However, during the experiments while keeping animals under constant light conditions, melatonin production was rarely naturally inhibited. For the experiments of this study, the method of constant lighting in the mouse model was applied. Our aim was to artificially evoke shift work conditions in order to find out how the deficiency of melatonin production influences the immune system of the shift workers. The results obtained showed that keeping mouse under constant lighting conditions the homeostasis of the immune system (antibody production, leukocyte and granulocyte migration) is disrupted. Therefore, shift work and its influence on the immune system could be considered as a factor for... [to full text] / Melatoninas – tamsiuoju paros metu kankorėžinėje liaukoje gaminamas hormonas. Šviesa nakties metu slopina melatonino produkciją. Melatoninas yra svarbus organizmo biologinis reguliatorius. Jis reguliuoja paros ir sezono bioritmus, gliukozės metabolizmą, lytinių liaukų aktyvumą, širdies ir kraujagyslių sistemos veiklą, virškinimo trakto veiklą, kitų endokrininių liaukų aktyvumą, imuninės sistemos veiklą. Literatūroje paskelbta nemažai duomenų apie imunoreguliacines melatonino savybes. Melatoninas panaikina su amžiumi susijusias užkrūčio liaukos ir blužnies involiucijas, skatina imuninės sistemos ląstelių proliferaciją, pagerina imuninį atsaką. Tyrinėjant imunoreguliacines melatonino savybes daugeliu atvejų taikomi tyrimo metodai, kurių metu atliekamos melatonino injekcijos arba pašalinama pagrindinė melatonino gamybos vieta - kankorėžinė liauka. Tačiau ankstesnių eksperimentų metu melatonino gamyba retai buvo natūraliai slopinama, laikant gyvūnus pastovaus apšvietimo sąlygomis. Disertacijos darbuose buvo taikytas pastovaus apšvietimo metodas modelinėje pelių sistemoje. Taip buvo siekta atkurti pamaininio darbo sąlygas ir ištirti galimą melatonino trūkumo poveikį žmonių, dirbančių pamaininį darbą, imuninei sistemai. Gauti rezultatai rodo, kad, laikant peles pastovaus apšvietimo sąlygomis, sutrinka jų imuninės sistemos homeostazė: antikūnų gamyba, leukocitų, granuliocitų migravimas. Dirbant pamaininį darbą reikėtų atkreipti dėmesį į jo poveikį imuninei sistemai ir įvertinti... [toliau žr. visą tekstą]

Melatoninas – tamsiuoju paros metu kankorėžinėje liaukoje gaminamas hormonas. Šviesa nakties metu slopina melatonino produkciją. Melatoninas yra svarbus organizmo biologinis reguliatorius. Jis reguliuoja paros ir sezono bioritmus, gliukozės metabolizmą, lytinių liaukų aktyvumą, širdies ir kraujagyslių sistemos veiklą, virškinimo trakto veiklą, kitų endokrininių liaukų aktyvumą, imuninės sistemos veiklą. Literatūroje paskelbta nemažai duomenų apie imunoreguliacines melatonino savybes. Melatoninas panaikina su amžiumi susijusias užkrūčio liaukos ir blužnies involiucijas, skatina imuninės sistemos ląstelių proliferaciją, pagerina imuninį atsaką. Tyrinėjant imunoreguliacines melatonino savybes daugeliu atvejų taikomi tyrimo metodai, kurių metu atliekamos melatonino injekcijos arba pašalinama pagrindinė melatonino gamybos vieta - kankorėžinė liauka. Tačiau ankstesnių eksperimentų metu melatonino gamyba retai buvo natūraliai slopinama, laikant gyvūnus pastovaus apšvietimo sąlygomis. Disertacijos darbuose buvo taikytas pastovaus apšvietimo metodas modelinėje pelių sistemoje. Taip buvo siekta atkurti pamaininio darbo sąlygas ir ištirti galimą melatonino trūkumo poveikį žmonių, dirbančių pamaininį darbą, imuninei sistemai. Gauti rezultatai rodo, kad, laikant peles pastovaus apšvietimo sąlygomis, sutrinka jų imuninės sistemos homeostazė: antikūnų gamyba, leukocitų, granuliocitų migravimas. Dirbant pamaininį darbą reikėtų atkreipti dėmesį į jo poveikį imuninei sistemai ir įvertinti... [toliau žr. visą tekstą] / Melatonin – is a hormone produced by the pineal gland during the dark time. Light during the night suppresses melatonin production. Melatonin is an important biological body regulator: it controls daily and seasonal biorhythms, glucose metabolism, gonadal activity, cardiovascular system, gastrointestinal tract and the activity of the immune system There is a lot of scientific information about the immunoregulative properties of melatonin. Melatonin modulates the development of some organs of the immune system, cell differentiation, immune response and cytokine production. The imunomodulatory activity of melatonin is usually determined by the following experimental models: surgical pinealectomy, in vivo treatment with melatonin or in vitro treatment of the immune cells with melatonin. However, during the experiments while keeping animals under constant light conditions, melatonin production was rarely naturally inhibited. For the experiments of this study, the method of constant lighting in the mouse model was applied. Our aim was to artificially evoke shift work conditions in order to find out how the deficiency of melatonin production influences the immune system of the shift workers. The results obtained showed that keeping mouse under constant lighting conditions the homeostasis of the immune system (antibody production, leukocyte and granulocyte migration) is disrupted. Therefore, shift work and its influence on the immune system could be considered as a factor for... [to full text]

Canada is the fourth largest producer of farmed salmon in the world, with Atlantic salmon being the major species cultivated. Paradoxically British Columbia (BC), which borders the Pacific Ocean, is the major producer province where Atlantic salmon was introduced in the mid-80’s. Escaped salmon may constitute a threat to natural populations of Pacific salmon as they compete for the same resources such as food and spawning territory. A potential solution to the aquaculture industry would be to further develop the aquaculture of native species in the region. The work presented here used semi-natural spawning channels to evaluate the effects of breeding strategies and early-rearing environments on the immune performance of Chinook salmon. Breeding strategy was tested analyzing artificial hatchery practices versus semi-natural propagation in spawning channels. Early-rearing environmental assessment contrasted indoor plastic hatchery tanks with outdoor gravelled-bottom spawning channels. A disease challenge involving over 1400 fish showed interaction effects between breeding strategy and rearing environment. Fish artificially mated presented a disease susceptibility influenced by the rearing environment. The contrary occurred in the offspring of self-breeding brood stock in the spawning channels, as no differences were observed in their susceptibility to the disease regardless of rearing environment. Monitoring of anti-Vibrio anguillarum antibodies during the disease challenge and a follow up of the survivors in sea net pens further confirmed the interaction between breeding strategy and rearing environment. Gene expression in pre- and post-infected artificially propagated fish showed differential gene expression when analyzed with a 695-gene cDNA microarray for Chinook salmon. Genotyping of major histocompatibility (MH) class II β1 alleles showed a tendency of a higher heterozygosity in survivors as expected, as well as a general tendency of a higher heterozygosity in semi-naturally propagated fish. The latter is likely a direct consequence of MH-linked mate choice, which was recently described in Chinook salmon (Neff et al., 2008). To further characterize the mating system of Chinook salmon in the spawning channels, brood stock were genotyped at 12 microsatellite loci. Females and males were found to mate randomly with regards to genetic pairwise relatedness, but they tended to mate with fish of similar condition as revealed by their pairwise differences in Fulton’s condition factor. This work demonstrated that genotype-by-environment interactions can modify the disease resistance of Chinook salmon. More importantly, these effects were seen after just one round of semi-natural spawning of domesticated hatchery fish, suggesting that further studies on spawning channels may highlight other hidden benefits. Therefore, breeding strategy and early-rearing environment should be considered when propagating cultured stocks. The use of more natural propagation methods such as spawning channels could improve the immune performance of Chinook salmon and help to expand the aquaculture of this native species in BC.

Obesity and type 2 diabetes (T2D) are associated with insulin resistance and increased levels of inflammation markers, suggesting activation of the immune system. However, the link between this so called ??low-grade inflammation?? and insulin resistance is poorly understood. In this thesis we aimed to investigate the direct effects of insulin on immune cells, and if these effects are changed in the setting of insulin resistance. We showed that insulin has anti-inflammatory effects by shifting T cell differentiation into a T helper type 2 phenotype. This effect was lost in insulin resistant subjects, which resulted in a more pro-inflammatory T helper type 1 cell hyperpolarisation. We also demonstrated that the Th1/2 balance is related to the degree of insulin resistance, and varies accordingly in clinical models of increasing or decreasing insulin resistance. Furthermore, we demonstrated that in a very early stage of pre-diabetes, where normal glucose tolerance and insulin sensitivity are still preserved, we cannot detect any immune activation, but we see a blunted food response of the appetite suppressant hormone PYY. Whilst this could put subjects at risk for further weight gain and development of obesity and T2D, we also demonstrated for the first time that PYY itself has strong anti-inflammatory properties, and that a deficiency in PYY could result in promoting a pro-inflammatory environment. In summary, we could demonstrate strong evidence that both, insulin and PYY are potent anti-inflammatory hormones which modulate immune function, and the observed deficiency in these hormones could contribute to further increase in inflammation and disease progression. Further work is indicated in this area to better understand the sequence and mechanism of immune activation, which may open up new therapeutic avenues for prevention and treatment of T2D.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.

Thesis (M.C.S.)--Carleton University, 2005. / Includes bibliographical references (p. 115-123). Also available in electronic format on the Internet.