Search results for "eläin"
showing 10 items of 169 documents
Moderate exercise in mice improves cancer plus chemotherapy-induced muscle wasting and mitochondrial alterations
2019
Cancer cachexia is a multifactorial syndrome characterized by anorexia, body wasting, and muscle and adipose tissue loss, impairing patient's tolerance to anticancer treatments and survival. The aim of the present study was to compare the effects induced in mice by tumor growth alone (C26) or in combination with chemotherapy [C26 oxaliplatin and 5-fluorouracil (oxfu)] and to evaluate the potential of moderate exercise. Oxfu administration to C26 mice exacerbated muscle wasting and triggered autophagy or mitophagy, decreased protein synthesis, and induced mitochondrial alterations. Exercise in C26 oxfu mice counteracted the loss of muscle mass and strength, partially rescuing autophagy and m…
The protective value of a defensive display varies with the experience of wild predators
2019
AbstractPredation has driven the evolution of diverse adaptations for defence among prey, and one striking example is the deimatic display. While such displays can resemble, or indeed co-occur with, aposematic ‘warning’ signals, theory suggests deimatic displays may function independently of predator learning. The survival value of deimatic displays against wild predators has not been tested before. Here we used the mountain katydid Acripeza reticulata to test the efficacy of a putative deimatic display in the wild. Mountain katydids have a complex defence strategy; they are camouflaged at rest, but reveal a striking red-, blue-, and black-banded abdomen when attacked. We presented live kat…
Auditory-evoked potentials to changes in sound duration in urethane-anesthetized mice
2019
Spectrotemporally complex sounds carry important information for acoustic communication. Among the important features of these sounds is the temporal duration. An event‐related potential called mismatch negativity indexes auditory change detection in humans. An analogous response (mismatch response) has been found to duration changes in speech sounds in rats but not yet in mice. We addressed whether mice show this response, and, if elicited, whether this response is functionally analogous to mismatch negativity or whether adaptation‐based models suffice to explain them. Auditory‐evoked potentials were epidurally recorded above the mice auditory cortex. The differential response to the chang…
Age affects myosin relaxation states in skeletal muscle fibers of female but not male mice
2018
The recent discovery that myosin has two distinct states in relaxed muscle–disordered relaxed (DRX) and super-relaxed (SRX)–provides another factor to consider in our fundamental understanding of the aging mechanism in skeletal muscle, since myosin is thought to be a potential contributor to dynapenia (age-associated loss of muscle strength independent of atrophy). The primary goal of this study was to determine the effects of age on DRX and SRX states and to examine their sex specificity. We have used quantitative fluorescence microscopy of the fluorescent nucleotide analog 2′/3′-O-(N-methylanthraniloyl) ATP (mantATP) to measure single-nucleotide turnover kinetics of myosin in skinned skel…
Polar Bear in 'Fortitude'. Affective Aesthetics and Politics of Climate Change
2021
In the first season of the television Eco Noir crime series “Fortitude” (2015) the polar bear appears as a sticky object that embodies an ambiguous affective charge as an icon of global warming. This article discusses the ways in which the polar bear evokes viewer affect in the series through two discourses. The first one relates to violence, essentially present in crime narratives, and how the human and nonhuman animal are positioned in relation to global warming, violence and each other. It raises questions of place and belonging in a local and global context and examines how the polar bear is constructed in terms of stranger danger and victimization in relation to human animals and the t…
Mammal assemblage composition predicts global patterns in emerging infectious disease risk
2021
Abstract As a source of emerging infectious diseases, wildlife assemblages (and related spatial patterns) must be quantitatively assessed to help identify high‐risk locations. Previous assessments have largely focussed on the distributions of individual species; however, transmission dynamics are expected to depend on assemblage composition. Moreover, disease–diversity relationships have mainly been studied in the context of species loss, but assemblage composition and disease risk (e.g. infection prevalence in wildlife assemblages) can change without extinction. Based on the predicted distributions and abundances of 4466 mammal species, we estimated global patterns of disease risk through …
Exercise and Metformin Intervention Prevents Lipotoxicity-Induced Hepatocyte Apoptosis by Alleviating Oxidative and ER Stress and Activating the AMPK…
2022
Objective. Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes (T2DM) commonly coexist and act synergistically to drive adverse clinical outcomes. This study is aimed at investigating the effects of exercise intervention and oral hypoglycaemic drug of metformin (MET) alone or combined on hepatic lipid accumulation. To investigate if oxidative stress and endoplasmic reticulum stress (ERS) are involved in lipotoxicity-induced hepatocyte apoptosis in diabetic mice and whether exercise and/or MET alleviated oxidative stress or ERS-apoptosis by AMPK-Nrf2-HO-1 signaling pathway. Methods. Forty db/db mice with diabetes ( random blood glucose ≥ 250 mg / dL ) were randomly allocated i…
The effect of social information from live demonstrators compared to video playback on blue tit foraging decisions.
2019
Video playback provides a promising method to study social interactions, and the number of video playback experiments has been growing in recent years. Using videos has advantages over live individuals as it increases the repeatability of demonstrations, and enables researchers to manipulate the features of the presented stimulus. How observers respond to video playback might, however, differ among species, and the efficacy of video playback should be validated by investigating if individuals’ responses to videos are comparable to their responses to live demonstrators. Here, we use a novel foraging task to compare blue tits’ (Cyanistes caeruleus) responses to social information from a live …
CVG-ICP-OES -menetelmän käyttö elohopean analysointiin eläinkudoksesta
2015
Tässä Pro gradu –tutkielmassa käsitellään elohopean määritystä eläinkudoksesta kemiallinen höyryn muodostus induktiivisesti kytketty plasma optinen emissio spektrometria –menetelmällä (CVG-ICP-OES) ja siihen liittyvää näytteenkäsittelyä. Tutkimuksen kirjallisessa osassa käydään läpi muun muassa eri näytteenliuotusmenetelmiä, analyysimenetelmiä, tutkittavien metallien pelkistämistä CVG-ICP-OES –analyysiä varten ja CVG-ICP-OES –analyysissä esiintyviä häiriöitä. Näytteenliuotusosassa keskitytään pääasiassa tutkimuksessa käytetyn ultraäänihajotuksen esittelyyn, tämän lisäksi myös muita yleisiä näytteenliuotusmenetelmiä esitetään. Analyysimenetelmä osiossa suurin huomio keskittyy ICP-OES –laitte…
Social transmission in the wild can reduce predation pressure on novel prey signals
2021
Funder: Suomen Kulttuurirahasto (Finnish Cultural Foundation); doi: https://doi.org/10.13039/501100003125