Search results for "ADP"

Increased dosage of Ink4/Arf protects against glucose intolerance and insulin resistance associated with aging

2013

Recent genome-wide association studies have linked type-2 diabetes mellitus to a genomic region in chromosome 9p21 near the Ink4/Arf locus, which encodes tumor suppressors that are up-regulated in a variety of mammalian organs during aging. However, it is unclear whether the susceptibility to type-2 diabetes is associated with altered expression of the Ink4/Arf locus. In the present study, we investigated the role of Ink4/Arf in age-dependent alterations of insulin and glucose homeostasis using Super-Ink4/Arf mice which bear an extra copy of the entire Ink4/Arf locus. We find that, in contrast to age-matched wild-type controls, Super-Ink4/Arf mice do not develop glucose intolerance with agi…

Mind the gap: Treefalls as drivers of parental trade-offs

2015

Abstract Tree‐fall gaps are small‐scale disturbances whose formation, colonization, and role in forest dynamics are well documented, but whose effects on animal ecology are still greatly overlooked, except for studies comparing species richness of gaps 6+ months old to that in the closed canopy. Other factors associated with the invasion of fresh tree‐fall gaps such as animal breeding adaptations have been largely neglected. I studied the immediate (within hours and days) arrival of the poison frog Dendrobates tinctorius in new tree‐fall gaps to examine the dynamics of their invasion in relation to tadpole rearing. I found that rearing sites are occupied sooner and tadpoles deposited at hig…

Regulation of Chromatin Remodeling through poly-ADP-ribosylation

2008

Physical inactivity increases oxidative stress, endothelial dysfunction, and atherosclerosis.

2005

Objective— Sedentary lifestyle is associated with increased cardiovascular events. The underlying molecular mechanisms are incompletely understood. Reactive oxygen species (ROS) contribute to endothelial dysfunction and atherosclerosis. An important source of vascular ROS is the NADPH oxidase. Methods and Results— C57BL6 mice were subjected to regular housing (physical inactivity) or voluntary training on running wheels (6 weeks). Inactivity increased vascular lipid peroxidation to 148±9% and upregulated superoxide release to 176±17% (L-012 chemiluminescence) and 188±29% (cytochrome C reduction assay), respectively. ROS production was predominantly increased in the endothelium and the medi…

Rho GTPases in human breast tumours: expression and mutation analyses and correlation with clinical parameters

2002

In the present study, we addressed the question of a putative relevance of Rho proteins in tumour progression by analysing their expression on protein and mRNA level in breast tumours. We show that the level of RhoA, RhoB, Rac1 and Cdc42 protein is largely enhanced in all tumour samples analysed (n=15) as compared to normal tissues originating from the same individual. The same is true for 32P-ADP-ribosylation of Rho proteins which is catalysed by Clostridium botulinum exoenzyme C3. Also the amount of Rho-GDI and ERK2 as well as the level of overall 32P-GTP binding acvitity was tumour-specific elevated, yet to a lower extent than Rho proteins. Although the amount of Rho proteins was enhance…

Activation of astroglial phospholipase D activity by phorbol ester involves ARF and Rho proteins.

2000

Primary cultures of rat cortical astrocytes express phospholipase D (PLD) isoforms 1 and 2 as determined by RT-PCR and Western blot. Basal PLD activity was strongly (10-fold) increased by 4beta-phorbol-12beta,13alpha-dibutyrate (PDB) (EC(50): 56 nM), an effect which was inhibited by Ro 31-8220 (0.1-1 microM), an inhibitor of protein kinase C (PKC), and by brefeldin A (10-100 microg/ml), an inhibitor of ADP-ribosylating factor (ARF) activation. Pretreatment of the cultures with Clostridium difficile toxin B-10463 (0.1-1 ng/ml), which inactivates small G proteins of the Rho family, led to a breakdown of the astroglial cytoskeleton; concomitantly, PLD activation by PDB was reduced by up to 50%…

Metabotropic glutamate receptors activate phospholipase D in astrocytes through a protein kinase C-dependent and Rho-independent pathway.

2003

Metabotropic glutamate receptors (mGluRs) are G protein-coupled receptors that mediate phospholipase D (PLD) activation in brain, but the mechanism underlying this response remains unclear. Here we used primary cultures of astrocytes as a cell model to explore the mechanism that links mGluRs to PLD. Glutamate activated both phospholipase C (PLC) and PLD with equal potency and this effect was mimicked by L-cysteinesulfinic acid, a putative neurotransmitter previously shown to activate mGluRs coupled to PLD, but not PLC, in adult brain. PLD activation by glutamate was dependent on Ca(2+) mobilization and fully blocked by both protein kinase C (PKC) inhibitors and PKC down-regulation, suggesti…

Gaviezes pagasta senlietu krātuves "Atmiņu pūrs" izveides nozīme vēstures liecību saglabāšanā un novadpētniecības attīstībā

2015

Novadpētniecības nozīme gadu gaitā pieaug, jo cilvēki arvien vairāk interesējas par savu kultūru, vēsturi un piederību. Cilvēkiem ir svarīgi būt piederīgiem un izjust piederības sajūtu. Novadpētniecība, kultūra, vēsture spēj veidot šo piederības sajūtu. Pētījuma mērķis ir izpētīt Gaviezes pagasta senlietu krātuves “Atmiņu pūrs” nozīmi novadpētniecībā un vēstures liecību turpmākā saglabāšanā. Pētījuma gaitā svarīgi uzzināt vietējo iedzīvotāju domas un vērtējumu par Gaviezē esošo senlietu krātuvi un tās darbību. Pētījuma rezultāti rāda, ka senlietu krātuve „Atmiņu pūrs” veic ļoti nozīmīgu novadpētniecības darbu. Senlietu krātuve Gaviezē ir nepieciešama, lai attīstītu un popularizētu vietējo n…

Spekku dzimta atmiņu stāstos un publikācijās

2022

Bakalaura darba mērķis ir apzināt un apkopot informāciju par Spekku dzimtu un tās nozīmīgumu Vecumnieku pagastā un Latvijā. Pētījuma procesā izpētīts Vecumnieku pagasta novadpētniecības centra krājums, Vecumnieku bibliotēkas novadpētniecības krājums. Veikta šo krājumu analīze. Pētījuma vajadzībām apskatītas pieejamās publikācijas Latvijas Nacionālās bibliotēkas Analītiskajā datubāzē un portālā Periodika.lv. Lai papildinātu iegūto informāciju par Spekku dzimtu ar nepublicētiem materiāliem un atmiņu stāstiem, iegūtas divas intervijas. Pētījuma rezultāti apliecina, ka Spekku dzimta ir pierādījusi spēju izdzīvot dažādos vēsturiski sarežģītajos laika periodos. Spekku dzimtas katra paaudze ieraks…

Novadpētniecība par Doles Tautas namu

2015

Doles Tautas nams ir sena ēka, kas tika izveidots kā Ķekavas krogs. Mūsdienās šajā namā notiek aktīva kultūras dzīve, kur tiek rīkoti dažādi pasākumi, kā arī ir aktuāla novadpētniecība. Pētījuma mērķis ir apkopot novadpētniecības informāciju par tautas namu, tā vēsturi, notikumiem, kas saistīti ar to, kā arī izpētīt mūsdienu situāciju. Pētījuma rezultāti rāda, ka Doles Tautas nams diezgan ilgu laiku ir darbojies kā izklaides vieta ceļotājiem, kur tiem bija iespēja piestāt un atpūsties, pašlaik ēkā atrodas galvenās Ķekavas pagasta kultūras iestādes.