• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 36
  • 30
  • 15
  • 6
  • 1
  • Tagged with
  • 88
  • 50
  • 32
  • 19
  • 19
  • 19
  • 16
  • 15
  • 11
  • 9
  • 9
  • 8
  • 8
  • 7
  • 7
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

A Systematic Review on the Cognitive Benefits and Neurophysiological Correlates of Exergaming in Healthy Older Adults

Stojan, Robert, Voelcker-Rehage, Claudia 02 July 2019 (has links)
Human aging is associated with structural and functional brain deteriorations and a corresponding cognitive decline. Exergaming (i.e., physically active video-gaming) has been supposed to attenuate age-related brain deteriorations and may even improve cognitive functions in healthy older adults. Effects of exergaming, however, vary largely across studies. Moreover, the underlying neurophysiological mechanisms by which exergaming may affect cognitive and brain function are still poorly understood. Therefore, we systematically reviewed the effects of exergame interventions on cognitive outcomes and neurophysiological correlates in healthy older adults (>60 years). After screening 2709 studies (Cochrane Library, PsycINFO, Pubmed, Scopus), we found 15 eligible studies, four of which comprised neurophysiological measures. Most studies reported within group improvements in exergamers and favorable interaction effects compared to passive controls. Fewer studies found superior effects of exergaming over physically active control groups and, if so, solely for executive functions. Regarding individual cognitive domains, results showed no consistence. Positive effects on neurophysiological outcomes were present in all respective studies. In summary, exergaming seems to be equally or slightly more effective than other physical interventions on cognitive functions in healthy older adults. Tailored interventions using well-considered exergames and intervention designs, however, may result in more distinct effects on cognitive functions.
32

Avalia??o participativa da qualidade do solo e sanidade dos cultivos para o manejo integrado da h?rnia das cruc?feras em ambiente de montanha / Participatory evaluation of soil quality and health of crops for integrated management of cruciferous clubroot in mountain environment

Carvalho, Eduardo Spitz de 31 March 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2018-09-11T12:50:42Z No. of bitstreams: 1 2016 - Eduardo Spitz de Carvalho.pdf: 2778180 bytes, checksum: 34e805f58061af534403ec60b6659541 (MD5) / Made available in DSpace on 2018-09-11T12:50:42Z (GMT). No. of bitstreams: 1 2016 - Eduardo Spitz de Carvalho.pdf: 2778180 bytes, checksum: 34e805f58061af534403ec60b6659541 (MD5) Previous issue date: 2016-03-31 / The municipality of Nova Friburgo is an important producer of brassica, in the Alto Rio Grande region, mainly cauliflower. This culture of great economic value has suffered with the incidence of clubroot causing huge losses, reaching 100% loss. For the prevention of the disease, it is necessary to understand that there is imbalance on the environment and that a change in the soil and crop management is crucial. In the region, young people have great importance in the production process and many of them study in technical courses offered by CEFFA (Centro Familiar de Forma??o por Altern?ncia) Col?gio Estadual Agr?cola (CEA) Rei Alberto I. The courses offered at the school work with the Pedagogy of Alternation. The aim of this study was to build with farmers and their children brassica crop management opportunities for minimizing impact of clubroot disease, with the association of local and academic knowledge. Therefore, we applied two questionnaires, one with 123 students from CEFFA CEA Rei Alberto I to the selection of the Production Units who grow brassicas and present incidence of clubroot, the other one, with 48 students, seeking to characterize the production systems, as for the topography, the main crops, and management strategies used to control the disease. At the end we selected eight production units (PUs) in different watersheds, distributed in the territorial space of the 3rd district, which were characterized by the history of clubroot in the production area, the forms of tillage, acidity correction and fertilization, seedlings source, planting season, crop rotation strategies, source of irrigation water and established strategies for coexistence with clubroot. Later, there were quality assessments of the soil, the health of crops and the potential for clubroot with students and their parents in each of the UPs. Soil samples were collected for fertility analysis. Then, there was a return of the reviews for farmers so they exchanged their joining knowledge. The management practices identified in the production units (PUs) evaluated in the 3rd District of Nova Friburgo- RJ have contributed to the spread and incidence of the disease. To live with the disease a change in the local production system design is necessary, pointing to new strategies regarding the encouragement of biotic and nutritional balance of soil and crop over the pathogen. The use of indicators to assess the local impact of potential hernia of cruciferous was efficient to point out the bottlenecks in the production of brassica system against the disease. The highly acidic pH and low Ca++ content in the soil, associated with frequent mechanization without cleaning the equipment might explain the high incidence of clubroot in the production units. The PUs require monitoring over time through evaluations of agro-ecosystems, using the tools presented in this study, as well as actions aimed at promoting the indicators towards sustainability, thus leading to the balance of soil, crops and biota / O munic?pio de Nova Friburgo ? importante produtor de br?ssicas na regi?o do Alto Rio Grande, principalmente, couve-flor. Esta cultura de grande valor econ?mico para o munic?pio vem sofrendo com a incid?ncia da h?rnia das cruc?feras com preju?zos de at? 100% de perda. Para preven??o da doen?a ? necess?rio o entendimento de que h? desequil?brio no ambiente e que a mudan?a no manejo do solo e da cultura ? imprescind?vel. Na regi?o, os jovens t?m grande import?ncia no processo de produ??o e grande parte desses estuda em cursos t?cnicos no CEFFA (Centro Familiar de Forma??o por Altern?ncia) Col?gio Estadual Agr?cola (CEA) Rei Alberto I, que funcionam com a Pedagogia da Altern?ncia. O objetivo desse trabalho foi construir participativamente junto aos agricultores e seus filhos possibilidades de manejo de cultivo de br?ssicas para o conv?vio com a doen?a h?rnia das cruc?feras, a partir da associa??o de conhecimentos locais e acad?micos. Para tanto, aplicou-se dois question?rios, um com os 123 alunos do CEFFA CEA Rei Alberto I para a sele??o das Unidades Produtivas que cultivam br?ssicas e que apresentam incid?ncia de h?rnia, o outro com 48 desses alunos, buscando caracterizar os sistemas de produ??o, quanto ao relevo, principais cultivos, e estrat?gias de manejo utilizadas para o controle da h?rnia. Ao final foram selecionadas oito unidades de produ??o (UPs) em diferentes microbacias, distribu?das no espa?o territorial do 3? distrito, as quais foram caracterizadas, quanto ao hist?rico da h?rnia das cruc?feras na ?rea de produ??o, formas de preparo do solo, corre??o da acidez e aduba??o, origem das mudas, ?poca do ano de plantio, estrat?gias de rota??o de cultivos, a origem da ?gua de irriga??o e as estrat?gias estabelecidas para a conviv?ncia com a h?rnia das cruc?feras. Posteriormente, foram avaliadas a qualidade do solo, a sanidade dos cultivos e a potencialidade para a h?rnia das cruc?feras, com os alunos e seus pais em cada UP. Foi coletado solos para an?lise de fertilidade. Posteriormente, foram retornadas as avalia??es para que os agricultores trocassem seus saberes. As pr?ticas de manejo identificadas nas unidades de produ??o (UPs) avaliadas do 3? Distrito de Nova Friburgo contribuem para dissemina??o e incid?ncia da doen?a. Para conviv?ncia com a doen?a deve ser mudada a concep??o do sistema produtivo local, apontando para novas estrat?gias para favorecimento do equil?brio bi?tico e nutricional do solo e das culturas em detrimento ao pat?geno. O uso de indicadores para avaliar a potencialidade de incid?ncia local da h?rnia das cruc?feras apontou os gargalos no sistema produtivo de br?ssicas em rela??o a doen?a. Os valores de pH, fortemente ?cidos, e os baixos teores de Ca no solo, associados a mecaniza??o frequente e sem limpeza dos equipamentos explicam a alta incid?ncia da h?rnia das cruc?feras nas unidades produtivas. As UPs necessitam acompanhamento ao longo do tempo, com avalia??es dos agroecossistemas, usando ferramentas como as apresentadas neste estudo, assim como a??es para promo??o dos indicadores no sentido da sustentabilidade, logo o equil?brio do solo, dos cultivos e da biota
33

Alterungsbedingte Effekte auf DNA-Methylierungsprofile entwicklungsrelevanter Gene in Eizellen und Embryonen am Modellorganismus Bos taurus / Aging-induced effects on DNA methylation profiles of developmental genes in oocytes and embryos on the model organism Bos taurus

Mattern, Felix January 2016 (has links) (PDF)
Die postovulatorische Alterung sowie die ovarielle Alterung konnten bei der Anwendung assistierter Reproduktionstechniken (ARTs) als entscheidende Faktoren identifiziert werden, die den Reproduktionserfolg nachhaltig beeinträchtigen. Die postovulatorische Alterung tritt ein, sobald die reife Eizelle nicht mehr innerhalb ihres physiologischen Zeitfensters befruchtet wird. Die ovarielle Alterung beschreibt hingegen die Abnahme des Follikel-Vorrats mit zunehmendem Alter des weiblichen Individuums bzw. des Ovars. Sowohl die postovulatorische Alterung als auch die ovarielle Alterung führen u.a. zu einer reduzierten Oozytenqualität und einer geringeren Blastozystenrate. Die Zielsetzung dieser Arbeit bestand darin, den Einfluss der postovulatorischen Alterung und der ovariellen Alterung im Holstein-Rind (Bos taurus) auf die DNA-Methylierung entwicklungsrelevanter Gene in Eizellen und Embryonen zu untersuchen. Aus Schlachthof-Ovarien wurden Antralfollikeln unterschiedlicher Größe (<2 mm, 3-5 mm und >6 mm) isoliert. Eizellen aus Follikeln der Größe 3-5 mm wurden für 24h (physiologisch) und 48h (gealtert) in vitro gereift (IVM). Die gereiften Oozyten wurden anschließend in vitro fertilisiert und Embryonen im 4-6 Zellstadium generiert. Sowohl in den unreifen Eizellen aus Antralfollikeln unterschiedlicher Größe als auch in den gereiften Oozyten und den Embryonen wurde die Promotormethylierung der Gene bH19, bSNRPN, bZAR1, bDNMT3A, bOCT4, bDNMT3Lo und bDNMT3Ls analysiert. Zur Untersuchung der ovariellen Alterung wurden mittelgroßen Antralfollikel aus Ovarien lebender Rinder (in vivo) unterschiedlichen Alters (9-12 Monate, 3-7 Jahre und 8-11 Jahre) gewonnen. In den daraus isolierten unreifen Eizellen wurde die DNA-Methylierung der Promotorregionen der Gene bTERF2, bREC8, bBCL-XL, bPISD, bBUB1, bDNMT3Lo, bH19 und bSNRPN bestimmt. Als Methode zur Analyse der Promotormethylierung wurde die Limiting Dilution Bisulfit-Sequenzierung angewendet. In unreifen Eizellen aus Antralfollikeln unterschiedlicher Größe (<2 mm, 3-5 mm und >6 mm) konnte ein erhöhtes Auftreten abnormal methylierter Allele in den geprägten Genen bH19 und bSNRPN von Eizellen kleiner Follikel (<2 mm) identifiziert werden. Dieses Ergebnis könnte eine mögliche Ursache einer bereits bekannten und mehrfach beschriebenen geringeren Entwicklungskompetenz von Eizellen kleiner Follikel (<2 mm) auf epigenetischer Ebene darstellen. Die verlängerte Reifungsdauer der IVM-Eizellen hatte eine signifikante Hypermethylierung in der Promotorregion des Gens DNMT3Lo von 48h-gereiften Eizellen zur Folge. Beim Übergang von 48h-gereiften Eizellen zum Embryo konnte eine signifikante Hypomethylierung von CpG7 des stammzellspezifischen Transkripts DNMT3Ls beobachtet werden. Diese CpG-Stelle wies ebenfalls einen signifikanten Anstieg von CpGs mit nicht-eindeutigem Methylierungszustand in unreifen Eizellen mit steigender Follikelgröße auf. Da sich die CpG-Position innerhalb eines Sequenz-Motivs einer Bindungsstelle des Transkriptionsfaktors CREB befindet, könnten die Methylierungsdaten auf eine Interaktion zwischen dem Transkriptionsfaktor CREB und der DNA-Methylierung während der Entwicklung und Reifung der Eizelle sowie der Transition von der Eizelle zum Embryo hindeuten. Die DNA-Methylierungsprofile der untersuchten Gene in unreifen Eizellen aus Kühen unterschiedlichen Alters (9-12 Monate, 3-7 Jahre und 8-11 Jahre) wiesen keine signifikanten Unterschiede zwischen den Altersgruppen auf. Die ovarielle Alterung bei Rindern zwischen 9 Monaten und 11 Jahren zeigte damit keinen Effekt auf die DNA-Methylierung der untersuchten Promotorregionen der Gene bTERF2, bREC8, bBCL-XL, bPISD, bBUB1, bDNMT3Lo, bH19 und bSNRPN. Nach einer simulierten postovulatorischen Alterung durch eine in vitro Reifung für 48h konnte eine Veränderung der DNA-Methylierung der Oozyten-spezifischen (DNMT3Lo) und Stammzell-spezifischen (DNMT3Ls) Promotoren des katalytisch inaktiven Cofaktors von DNMT3A, DNMT3L, beobachtet werden. Die veränderte DNA-Methylierung von DNMT3Ls tritt dabei erst im frühen Embryo in Erscheinung und interagiert vermutlich mit dem Transkriptionsfaktor CREB. Die Veränderungen von DNMT3Lo in Eizellen und DNMT3Ls in den daraus generierten Embryonen lässt vermuten, dass es sich hierbei um eine dynamische Anpassung des Embryos auf äußere Umweltbedingungen der Eizelle über die Methylierung der DNA handelt. / Postovulatory aging and ovarian aging have been identified as key factors in assisted reproductive techniques (ARTs) and have a lasting effect on reproductive success. Postovulatory aging occurs if the mature egg is not fertilized within its physiological time window. On the other hand, ovarian aging describes the decrease in the follicular reserve with increasing age of the female or the ovary, respectively. Both post-ovulatory aging and ovarian aging result in reduced oocyte quality and lower blastocyst rate. The aim of this thesis was to explore the effects of postovulatory aging and ovarian aging in Holstein cattle (Bos taurus) on the DNA methylation of developmentally important genes in oocytes and embryos. Antral follicles of different sizes (<2 mm, 3-5 mm and> 6 mm) were isolated from slaughterhouse ovaries. Female germ cells from middle-sized follicles (3-5 mm) were matured for 24h (physiological conditions) and 48h (aged conditions) in vitro (IVM). The IVM- oocytes were subsequently fertilized in vitro and embryos at the 4-6 cell stage were generated. Promoter methylation of the genes bH19, bSNRPN, bZAR1, bDNMT3A, bOCT4, bDNMT3Lo and bDNMT3Ls was analysed in immature oocytes from antral follicles of different sizes as well as in matured oocytes and the respective embryos. For studying ovarian aging, middle-sized antral follicles were obtained in vivo from animals of different age groups (9-12 months, 3-7 years and 8-11 years). In the extracted immature gametes, the DNA methylation of the promoter regions of bTERF2, bREC8, bBCL-XL, bPISD, bBUB1, bDNMT3Lo, bH19 and bSNRPN was examined. The limiting dilution bisulfite (pyro)sequencing method was applied to determine the promoter methylation of the candidate genes at the single allele level. In immature oocytes from antral follicles of different diameters (<2 mm, 3-5 mm and> 6 mm) an increased occurrence of abnormally methylated alleles of the imprinted genes bH19 and bSNRPN was identified in small follicles (<2 mm). This failure to establish imprinting could be a possible cause of a well-known reduced developmental potential of small follicles (<2 mm) at the epigenetic level. The extended maturation time of the IVM-oocytes resulted in a significant hypermethylation in the promoter region of DNMT3Lo in 48h matured oocytes. After transition from 48h matured oocytes to embryos, a significant hypomethylation of CpG7 of the stem cell specific transcript DNMT3Ls was detected. The same CpG site showed a significant increase of CpGs with unclear methylation state in immature female germ cells with increasing follicular size. This CpG position is located within a potential binding site of the transcription factor CREB. Thus, the methylation data indicates an interaction between the transcription factor CREB and the DNA methylation during development and maturation of oocytes as well as during transition from the oocyte to the embryo. The DNA methylation profiles of the analysed genes in immature oocytes from cows of different age (9-12 months, 3-7 years and 8-11 years) showed no significant differences between age groups. Hence, the ovarian aging in cattle between 9 months and 11 years caused no effect on the DNA methylation of bTERF2, bREC8, bBCL-XL, bPISD, bBUB1, bDNMT3Lo, bH19 and bSNRPN. After a simulated postovulatory aging by in vitro maturation for 48h, a change in the DNA methylation of the oocyte-specific (DNMT3Lo) and stem cell-specific (DNMT3Ls) promoters of the catalytically inactive DNA-methyltransferase DNMT3L was observed. The altered DNA methylation of DNMT3Ls occurs in the early embryo and probably interacts with the transcription factor CREB. The changes of DNMT3Lo in oocytes and DNMT3Ls in the resulting embryos might represent a dynamic adaptation to external environmental conditions.
34

Entwicklung der körperlichen Leistungsfähigkeit : eine prospektive Längsschnittstudie mit Personen im mittleren und späteren Erwachsenenalter /

Tittlbach, Susanne, January 2002 (has links)
Originally presented as the author's Thesis (doctoral)--Karlsruhe Universität, 2001. / Includes bibliographical references (p. 239-256).
35

Type 2 Diabetes in Octogenarians Is Associated with Decreased Low Molecular Weight Adiponectin

Gräßler, Jürgen, Gruber, Matthias, Radke, Rolf-Bernd, Kopprasch, Steffi, Schwarz, Peter E. H., Kamke, Wolfram, Bornstein, Stefan R., Fischer, Sabine 21 February 2014 (has links) (PDF)
Background: Adiponectin circulates in the blood in three different multimer isoforms, of which the high molecular weight form (HMW) is presumed to mediate insulin sensitivity. We examined whether adiponectin oligomer distribution is associated with aging and type 2 diabetes (T2D) in octogenarians without characteristic features of metabolic syndrome. Methods: The study included 154 octogenarians (58 men, 96 women), 24 normoglycemic middle-aged controls (11 men, 13 women; mean age 44 years), and 33 middle-aged individuals (14 men, 19 women; mean age 55 years) with T2D. Based on oral glucose tolerance test 62 octogenarians had normal, 63 impaired glucose tolerance, and 29 octogenarians had newly detected T2D. Serum adiponectin multimer isoforms were measured after overnight fast by enzyme-linked immunosorbent assays. Results:Compared to the normoglycemic middle-aged control group, male normoglycemic octogenarians revealed significantly higher total adiponectin and all adiponectin isoforms. The same was true for females with the exception of low molecular weight (LMW) adiponectin, which was not statistically higher in octogenarians. Male and female octogenarians with T2D had significantly higher levels of total, HMW, and middle molecular weight (MMW) adiponectin, but not LMW adiponectin, than middle-aged individuals with T2D. Female, but not male, octogenarians revealed significantly lower total adiponectin than normoglycemic octogenarians. Compared with normoglycemic octogenarians, male and female octogenarians with T2D were characterized by significantly lower LMW adiponectin. In male and female octogenarians, total adiponectin and all multimer isoforms were directly correlated with HDL cholesterol. LMW adiponectin in octogenarians of both sexes was inversely correlated with glucose level at 2-hour oral glucose tolerance test. Conclusions: Serum levels of total adiponectin as well as its HMW and MMW isoforms were significantly higher in octogenarians with normoglycemia or T2D than in corresponding middle-aged control groups. In male and female octogenarians without metabolic syndrome, T2D was associated with lower LMW adiponectin, while the HMW and MMW isoforms were not statistically different. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
36

Die Untersuchung der replikativen Seneszenz kaniner dermaler Fibroblasten als Beitrag zur Alternsforschung

Streit, Susanne 15 May 2006 (has links) (PDF)
Mit der vorliegenden Arbeit sollte nachgewiesen werden, dass bei in vitro kultivierten kaninen dermalen Fibroblasten einer Hunderasse nach einer bestimmte Kultivierungszeit replikative Seneszenz entsteht und dass das replikative Vermögen dieser Zellen in der Zellkultur abhängig vom Alter des Spendertieres ist. Dreißig Beagle aus zwei Versuchstieranstalten wurden als Hautspender genutzt. Diese Tiere wurden in die drei Altersgruppen jung, adult und alt unterteilt. Mit Hilfe einer Hautstanze wurde bei allen Tieren im Bereich der rechten Skapula ein Hautstück gewonnen. Diese Hautstücken wurden in Zellkulturflaschen verbracht. Die aus diesem Explantat auswandernden Zellen stellten die Grundlage für die Primärkultur dar. Die Zellen wurden in regelmäßigen Abständen subkultiviert. Dabei wurden immer die Gesamtzellzahl und die Vitalität der Kulturen bestimmt. Diese Werte bildeten die Grundlage für die Berechnung der Parameter des replikativen Vermögens der Zellen. Auf Grundlage der erstellten Wachstumskurven konnte die Generationszeit der Zellen berechnet werden. Parallel zur Kultivierung der Zellen erfolgte die morphologische Betrachtung der Zellen mit Hilfe eines Phasenkontrastmikroskops und histologischen Färbungen, die unter dem Lichtmikroskop näher beurteilt wurden. / This thesis aims to demonstrate that, after a certain period of time, replicative senescence develops in canine dermal fibroblasts of a certain dog breed when cultured in vitro. It is also shown that the replicative capacity of these cells is related to the age of the donor animal. Thirty Beagles from two experimental facilities were used as skin donors. The animals were divided in three age groups: young, adult and old. Skin samples from the right scapula were taken from all animals by means of a punch biopsy and transferred to cell culture vessels. The primary culture was based on the cells emigrating from these explants. The cells were subcultured at regular intervals, at which the total number of cells and the vitality of the cultures were also determined. Based on these parameters, the replicative capacity of the cells was calculated and growth curves were created, which were then used to calculate the generation times of the cells. Parallel to cultivation, the cells underwent morphological dissection using a phase contrast microscope on the one hand and a light-optical microscope with histological staining on the other hand.
37

Zelluläre und molekularbiologische Grundlagen der vorzeitigen Alterung humaner Fibroblasten nach Bestrahlung mit Röntgenstrahlen und Kohlenstoff-Ionen

Winter, Marcus. Unknown Date (has links) (PDF)
Darmstadt, Techn. Universiẗat, Diss., 2007.
38

Type 2 Diabetes in Octogenarians Is Associated with Decreased Low Molecular Weight Adiponectin

Gräßler, Jürgen, Gruber, Matthias, Radke, Rolf-Bernd, Kopprasch, Steffi, Schwarz, Peter E. H., Kamke, Wolfram, Bornstein, Stefan R., Fischer, Sabine January 2011 (has links)
Background: Adiponectin circulates in the blood in three different multimer isoforms, of which the high molecular weight form (HMW) is presumed to mediate insulin sensitivity. We examined whether adiponectin oligomer distribution is associated with aging and type 2 diabetes (T2D) in octogenarians without characteristic features of metabolic syndrome. Methods: The study included 154 octogenarians (58 men, 96 women), 24 normoglycemic middle-aged controls (11 men, 13 women; mean age 44 years), and 33 middle-aged individuals (14 men, 19 women; mean age 55 years) with T2D. Based on oral glucose tolerance test 62 octogenarians had normal, 63 impaired glucose tolerance, and 29 octogenarians had newly detected T2D. Serum adiponectin multimer isoforms were measured after overnight fast by enzyme-linked immunosorbent assays. Results:Compared to the normoglycemic middle-aged control group, male normoglycemic octogenarians revealed significantly higher total adiponectin and all adiponectin isoforms. The same was true for females with the exception of low molecular weight (LMW) adiponectin, which was not statistically higher in octogenarians. Male and female octogenarians with T2D had significantly higher levels of total, HMW, and middle molecular weight (MMW) adiponectin, but not LMW adiponectin, than middle-aged individuals with T2D. Female, but not male, octogenarians revealed significantly lower total adiponectin than normoglycemic octogenarians. Compared with normoglycemic octogenarians, male and female octogenarians with T2D were characterized by significantly lower LMW adiponectin. In male and female octogenarians, total adiponectin and all multimer isoforms were directly correlated with HDL cholesterol. LMW adiponectin in octogenarians of both sexes was inversely correlated with glucose level at 2-hour oral glucose tolerance test. Conclusions: Serum levels of total adiponectin as well as its HMW and MMW isoforms were significantly higher in octogenarians with normoglycemia or T2D than in corresponding middle-aged control groups. In male and female octogenarians without metabolic syndrome, T2D was associated with lower LMW adiponectin, while the HMW and MMW isoforms were not statistically different. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
39

Neural stem cell expansion rejuvenates learning strategies and memory throughout life

Berdugo-Vega, Gabriel 03 February 2021 (has links)
Der Hippocampus ist ein Hirnareal welches fundamental für die Generierung von bewussten Erinnerungen und für die Etablierung von flexiblen Beziehungen zwischen kontextuellen Repräsentationen ist. Hippocampale Fehlfunktion während des Alterns wurde als ein Schlüsselfaktor für den kognitiven Abbau vorgeschlagen und im Kontext einer schnell alternden Bevölkerung wird es zwingend notwenig, mögliche Mechanismen zu verstehen, die diese Einschränkungen verhindern oder rückgängig machen können. Der Hippocampus ist ein von nur zwei Arealen im Gehirn, in dem neue Neuronen ständig im Erwachsenenleben erzeugt werden. Deren Rolle beim Lernen und bei Gedächtnisfunktionen ist jedoch nicht gut verstanden. Interessanterweise wurde adulte hippocampale Neurogenese als eine zelluläre Komponente eines Gehirnreservenmechanismus vorgeschlagen, mit dem Potenzial kognitive Fähigkeiten ein Leben lang zu erhalten sowie ein mögliches Ziel für therapeutische Ansätze darzustellen. In dieser Arbeit habe ich eine spezifische, genetisch-bedingte Expandierung von hippocampalen Nervenstammzellen genutzt, um deren intrinsisches Potenzial, neugeborene Neuronen zu erzeugen, auszuschöpfen, was zu einer lebenslangen erhöhten Neurogenese geführt hat. Dies hat die hippocampale Funktion auf mehreren Ebenen gefördert, vom verbesserten flexiblen Lernen in Navigationsaufgaben in der Jugend, über Kompensation des altersbedingten kognitiven Abbaus bis hin zur Verjüngung von kontextuellem Gedächtnis beim Altern. Zusammengefasst stellt meine Arbeit ein besseres Verständnis des funktionellen Beitrags der Neurogenese zu Lernen und Gedächtnis zur Verfügung and zeigt, dass kritische Aspekte hippocampaler kognitiver Beeinträchtigung im Alter rückgängig gemacht oder ein Leben lang durch extrinsische Ausnutzung der endogenen Hirnreserven kompensiert werden können.
40

Funktionelle Neuroplastizität im primären somatosensorischen Kortex durch Erlernen neuer motorischer Fertigkeiten - Ein Vergleich zwischen jungen und alten Erwachsenen mittels somatosensibler evozierter Potentiale

Predel, Claudia 06 April 2023 (has links)
No description available.

Page generated in 0.0486 seconds