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Effets d'un décalage horaire "simulé" et d'une sieste sur les performances physiques et psychomotrices du sportif / Effects of a simulated jet lag and short nap on physical and psychomotor performances in athletesPetit, Élisabeth 09 December 2013 (has links)
Résumé : Chez le sportif, le franchissement de plusieurs fuseaux horaires avec décalage horaire s'accompagne d'une fatigue avec somnolence diurne, d'une diminution des performances cognitives, sportives et de la vigilance. Une sieste de courte durée pourrait être une solution adaptée pour prévenir les effets du jet lag. A notre connaissance, aucune étude n'a évalué les effets d'une sieste et/ou les effets combinés du décalage horaire et d'une sieste sur les performances des athlètes.C'est pourquoi, l'objectif de cette thèse est d'étudier chez des athlètes, les effets d'une avance de phase de 5 heures (simulant un voyage transméridien vers l'Est) et d'une sieste post-prandiale de 20 minutes sur les réponses à un exercice physique de courte durée et à des tâches psychomotrices ainsi que sur le sommeil subséquent. Seize sujets jeunes, sains, de sexe masculin et sportifs (âge : 22.2 ± 1.7 ans ; taille : 178.3 ± 5.6 cm, poids : 73,6 ± 7,9 kg ; VC>2 max : 55.5 ± 9,1 ml.min.kg"' ; siesteurs non habituels) ont participé à cette étude. Aucun ne présentait de pathologie du sommeil. Chaque sujet a passé en laboratoire une nuit d'habituation et 8 nuits expérimentales dont 4 en condition normale (23H-7H, 2 nuits pré-tests et 2 post-tests) et 4 en avance de phase de 5 h ( 18H-2H, 2 nuits pré et 2 post-tests) avec enregistrement EEG continu. Après un repas standardisé au laboratoire, les sujets ont été soumis, entre 13 et 14H (condition normale), et entre 08 et 09H (condition de décalage), soit à une sieste (20 min de sommeil), soit à une période de repos en décubitus sans sommeil. A l'issue, les sujets ont réalisé un test de performance attentionnelle, évaluant 6 champs de l'attention, un test de Handgrip et un test Wingate avec mesure de la lactatémie en fin d'exercice et lors de la récupération. Ces mêmes tests ont été reconduits 2 heures plus tard dans le même ordre. La température rectale a été enregistrée par holter tout au long de la période expérimentale.Les résultats montrent que le décalage horaire modifie l'architecture du sommeil de la nuit pré tests avec un déficit de sommeil d"lh20, se traduisant par une moindre efficacité de sommeil. En revanche, ce décalage améliore la qualité du sommeil de la nuit subséquente (post-tests) avec une augmentation de la quantité du N3 et du sommeil paradoxal. Une baisse significative de l'amplitude de la température interne témoigne d'un réajustement actif des sujets. L'architecture de la sieste (stades 2 et 3) est similaire qu'elle ait lieu après une nuit normale ou après décalage horaire avec toutefois une quantité de SP qui tend à augmenter après la nuit en avance de phase. Elle n'a pas d'effets sur la composition du sommeil qui suit (condition normale ou en décalage), en dehors d'une augmentation de la latence d'endormissement en condition de décalage... / Purpose T he aim of thé study vvas to examine thé effects of a post-prandial 20 min nap on a short-term physicalexercise and subséquent sleep in athlètes keeping their usual sleep schedules and in 5-h phase-advance condition.Methods Sixteen healthy young mâle athlètes (âge 22.2 ± 1.7 years. non-habitual nappers) participated in thé study.After a baseline 8-h time in bed in normal and 5-h advanced sleep schedules, a standardized moming and lunch in alaboratory enviromnent, subjects undervvent either a nap (20 min of sleep elapsed from 3 epochs of stage 1 or 1 epochof stage 2), or a rest without sleep by lying in a bed, between 13:00 and 14:00 hours in non-shifted condition or 08:00and 09:00 hours in shifted condition, after vvhich anaerobic exercises were perforrned tvvice 2 h apart. Core bodytempérature vvas recorded throughout thé study period.Resuhs The nap extended sleep onset latency from6.72 ± 3.83 to 11.84 ± 13.44 min, after shifted condition but did not modify sleep architecture of thé post-trial nightamong athlètes, vvhether shifted or not. Moreover, napping did not improve physical performance but it delayedacrophase and batyphase of core body température rhythm pararneters.Conclusion N apping showed no reliable benefit on short-term performances of athlètes exercising at local time or aftera simulated jet lag.
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The behavioural thermoregulation and ecophysiology of the leopard tortoise (Geochelone pardalis) in the Nama-Karoo.McMaster, Megan Kay. 30 May 2014 (has links)
The leopard tortoise (Geochelone pardalis) is the largest of the southern African tortoise
species and has a wide distribution range. However, there is a lack of ecological and
physiological information about the species, especially arid and semi-arid regions. The
Nama-Karoo, an arid region of South Africa, is subject to large fluctuations in rainfall, food
availability and ambient temperatures (Ta). This study focused on the thermal behaviour,
thermoregulatory, digestive and metabolic plasticity of the leopard tortoise within the Nama-
Karoo biome.
Seasonal changes in activity patterns and body temperature (Tb) were investigated in
free ranging leopard tortoises in the Nama-Karoo. Leopard tortoises had unimodal daily
activity patterns in winter, bimodal in summer, and there were daily and seasonal differences
in the extent to which certain behaviours were practiced. Daily activity behaviours were
executed at lower Tb and at lower Ta in winter compared to summer. In summer, core Tb of
all tortoises oscillated on a daily basis well below maximum Ta, while core Tb of all tortoises
in winter oscillated well above the daily Ta range. Tortoises were therefore able to maintain
their Tb independently of Ta. Differences in Tb as measured from various positions on the
tortoises body was investigated in relation to Ta. There was a strong seasonal and temporal
influence on the relationship between various Tb’s, with the skin and external shell
temperatures being more variable in response to fluctuating Ta’s compared with cloacal and
core Tb. Cloacal temperatures were significantly different to other Tb measurements
suggesting that it should be treated with circumspection as an exclusive measure of Tb.
Heating and cooling rates of leopard tortoises were investigated in the field and under
controlled laboratory conditions to determine if the tortoises maximise operational daily
activity periods, and to determine the effect of behaviour and size on the rate of heat flux. In
the laboratory, cooling rates were faster than heating rates in summer and winter for all size
classes and decreased with increasing body mass. Leopard tortoises had significantly faster
heating and cooling rates in winter than in summer. Free-ranging leopard tortoises had faster
heating rates than cooling rates and their heat flux was largely independent of Ta. Heating
and cooling rates were dependant on body mass and surface area-to-volume ratio of
individuals. Under experimental conditions, tortoises physiologically adjusted their rate of
heat flux, while free-ranging tortoises used physiological and behavioural mechanisms to
minimise the risk of overheating, to aid thermal inertia and maximise operative activity time.
Seasonal climatic cycles and fluctuating daily temperatures influence the oxygen
consumption (VO2) of reptiles, however the result of these effects on metabolism in
chelonians is poorly understood. The effect of seasonal and daily differences in Ta on VO2
was investigated. Leopard tortoises’ VO2 was slightly higher than reported for other
chelonians. There were significant differences in tortoise VO2 at different Ta’s during the day
and night and in different seasons. This metabolic plasticity is possibly an adaptive
mechanism to cope with unpredictable environmental conditions.
Unpredictable climatic conditions lead to unpredictable food and water availability.
Little is known how tortoises adjust dietary parameters in response to food type and water
availability, and if this affects body mass, energy and water balance. Therefore this study
also considered whether leopard tortoises adjusted food transit rate, food intake and water
loss to cope with a diet fluctuating in fibre and water content, and whether body mass, energy
and water balance were maintained. Leopard tortoises fed a high fibre, low water content diet
had lower food intake rates, longer food transit times, but lower daily energy assimilation
compared with tortoises fed a low fibre, high water content diet. Tortoises fed a high fibre,
low water content diet had lower urine osmolality, but similar total water loss to those fed a
high fibre, low water content diet. The results indicate that tortoises can adjust digestive
parameters according to diet composition and exercise some control over energy and water
balance.
It is concluded that leopard tortoises show a high degree of plasticity in their thermal
behaviour and physiology which allows survival in an unpredictable environment,
particularly where there are fluctuations in rainfall, food availability and Ta’s. Seasonal and
daily variation in thermoregulation, metabolic rate and the uptake of energy allows the
leopard tortoise to maximise the duration of operative temperature, to minimise energy loss
and to use variable and unpredictable seasonal resources. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.
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Integrated physiology and behaviour of Thallomys nigricauda along an aridity gradient.Coleman, Joy Carol. January 2008 (has links)
Climate change predictions suggest that the continent most vulnerable to climate
change is Africa. The impacts of potential changes which include increases in air
temperatures and rainfall variability are negative with potential species extinctions
projected throughout southern Africa. A number of climate models have been applied
to examine the consequences of climate change for ranges of South African animal
species. One such model frequently predicted range shifts from west to east, which is
realistic considering the marked aridity gradient in an east-west direction across the
country, but the authors suggested that these shifts may not be as marked if species
are able to use physiological and behavioural methods to adapt to an increase in
aridity. Information on the degree to which behavioural and physiological flexibility
affect species range in southern Africa is scant which is surprising given its
importance with regard to climate change.
Thallomys nigricauda occurs along an east-west aridity gradient in southern
Africa, inhabiting mesic, semi-xeric and xeric regions. One would expect phenotypic
flexibility in physiological and behavioural traits in response to the diverse
environmental conditions to be related to the success and range of the species. The
wide distribution and arboreal habits, suggesting that T. nigricauda is exposed to
greater extremes of temperature than fossorial rodents, makes T. nigricauda an ideal
species to test this assumption. Hence I expected that T. nigricauda would exhibit
variation in physiological and behavioural traits measured along an aridity gradient.
This has important implications in predicting the survival of small mammal species in
the light of climate change in southern Africa.
Thallomys nigricauda were live-trapped in winter 2006 and 2007 and summer
2007 using Elliot traps in three sites: mesic site Weenen Game Reserve (KwaZuluiv
Natal Province, South Africa); semi-xeric site Haina Game Farm (Botswana) on the
northern boundary of the Central Kalahari Desert and xeric site Molopo Nature
Reserve (southern Kalahari savannah, North-West Province, South Africa).
I studied the home-range size of T. nigricauda by radiotracking 12 males and
16 females in winter 2006, 2007 and summer 2007. Home ranges were estimated
using 100% and 95% minimum convex polygons and 95% and 50% fixed kernels.
Home ranges varied widely, from 166 to 80199m2 for males and from 46 to 8810m2
for females. Males had larger home ranges than females, which supports a
promiscuous mating system reported for the species. Although range size was reduced
in both sexes in winter, this was not significant. I found no significant difference in
home range size along the aridity gradient. It is suggested that a combination of
precipitation, habitat productivity and breeding system influences the size of home
range of the species, and that this species displays phenotypic flexibility in terms of its
behavioural responses to these factors.
I measured the urine concentrating ability (UCA), as indicated by urine
osmolality and relative medullary thickness (RMT), and water turnover rate (WTR) of
T. nigricauda. There was no significant difference in RMT between sites or sex and
no difference in osmolalities when site, season and sex were taken into account. In
addition, specific WTR was not significantly influenced by season. Lack of significant
differences could be the result of the high degree of individual variation in the traits
measured, an indication of the flexibility in UCA and WTR. However, higher urine
osmolality and lower WTR’s were recorded in the dry winter months.
I quantified the thermal environment perceived by a small, arboreal,
mammalian endotherm using a number of methods at three study sites in winter and
summer. Our area of interest was how well these methods accurately portrayed the
actual temperatures that small mammals are exposed to. Temperature differences
between the methods were largest during the midday, when temperatures were
highest. All methods recorded a greater range of temperatures during photophase than
during scotophase. Black-bulb and model temperatures produced more accurate, rapid
measurements when compared to measurements produced by direct temperature
recording devices, particularly during photophase, when solar radiation is the major
influence of heating. Other methods lagged behind black-bulb measurements.
Although the mean temperatures of some of the methods were significantly different,
there was a high degree of correlation between all methods, even after randomization
and generation of 25% and 10% subsamples. Computed thermal indices and blackbulb
temperatures produced similar thermal profiles. In studies requiring accurate
time series measurements, it is suggested that black-bulb or copper models be
employed rather than direct temperature recording devices. Simpler measurement
devices would suffice for studies requiring an estimate of the temperature variation
and trends in the microclimate of small mammalian endotherms, particularly arboreal
or cavity dwelling species.
In the wild, across an aridity gradient, I measured abdominal body
temperarture (Tb) of T. nigricauda using implanted iButtons®. All but three T.
nigricauda displayed significant 24 h Tb rhythmicity. The Tb range for free-living T.
nigricauda was 32.33-40.63 oC (n = 13) and 32.69-40.15 oC (n = 17) in winter and
summer respectively. Although there was variation in Tb profiles, T. nigricauda
generally displayed a bimodal distribution of Tb, with high and low Tb values during
scotophase and photopase respectively. Body temperature range was significantly
greater in winter, when T. nigricauda reduced its minimum Tb. It was shown that the
maximum amplitude of circadian rhythms of body temperature was on average
259.6% of expected values. To determine the extent to which the microclimate of T.
nigricauda cavities assists in the maintenance of Tb, I measured the temperatures of
cavities across the gradient, providing an indication of the degree of buffering
provided by refugia. I measured the temperatures of shallow and deep regions of
cavities using iButtons® in summer and winter and recorded operative and shade
temperatures for comparison. Compared with operative temperature, cavities had
stable microclimates, displaying smaller ranges in temperature. Mean minimum and
maximum cavity temperatures differed significantly to operative temperature and
between seasons, whereas there was no significant difference between shallow and
deep measurements in cavities. Differences in the buffering capacities of the cavities
between seasons were not significant. To determine whether T. nigricauda alter its
length of exposure in response to lower ambient temperatures in winter as a means of
maintaining Tb, I measured the activity of T. nigricauda, defined as the proportion of
fixes outside the home cavity of the individual. Males spent a greater proportion of the
active phase away from their home cavity in summer, and significantly in winter
when compared with females, but there were no differences between seasons. It is
suggested that T. nigricauda realize energy savings by lowering its Tb during their rest
phase during the day, allowing them to maintain nocturnal activity and overall energy
balance.
Thus, besides the larger male home range, a result of the reproductive pattern,
the physiological and behavioural traits of T. nigricauda measured in this study did
not differ between aridity sites or seasons. The results of this study, in highlighting the
variation in physiological and behavioural responses of subpopulations of T.
nigricauda to diverse conditions, suggest that this variation is due to phenotypic
flexibility. Understanding the extent and nature of this flexibility is critical to our
comprehension of the consequences climate change. By defining the presence and
extent of intraspecific variation in physiology and behaviour, this study resolved the
necessary first step towards this understanding for the widely distributed T.
nigricauda in southern Africa. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
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Metabolisches Syndrom: Die Effekte von 20-Hydroxyecdyson und 17-beta-Östradiol auf das Fettgewebe und die subkutane Körpertemperatur der ovariektomierten Ratte / Metabolic Syndrome: Effects of 20-hydroxyecdysone and 17-beta-estradiol on fat and subcutaneous body temperature of ovariectomized ratsPettenkofer, Moritz 09 December 2014 (has links)
No description available.
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Human responses to cold and wind /Gavhed, Désirée, January 2003 (has links) (PDF)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 6 uppsatser.
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Molecular and Behavioral Analysis of <em>Drosophila</em> Circadian Photoreception and Circadian Thermoreception: A DissertationBusza, Ania 23 May 2007 (has links)
Circadian clocks are biological timekeepers that help maintain an organism’s behavior and physiological state optimally timed to the Earth’s day/night cycle. To do this, these internal pacemakers must accurately keep track of time. Equally importantly, they must be able to adjust their oscillations in response to external time cues to remain properly synchronized with the environment, and correctly anticipate environmental changes. When the internal clock is offset from its surrounding day/night cycle, clinically relevant disruptions develop, ranging from inconveniences such as jet-lag to more severe problems such as sleep disorders or mood disorders. In this work, I have used the fruit fly, Drosophila melanogaster, as a model organism to investigate how light and temperature can synchronize circadian systems.
My initial studies centered on an intracellular photoreceptor, CRYPTOCHROME (CRY). CRY is a blue light photoreceptor previously identified as a major component of the primary light-input pathway into the Drosophila circadian clock. We used molecular techniques to show that after light-activation, CRY binds to the key circadian molecule TIMELESS (TIM). This interaction irreversibly targets TIM, but not CRY, for degradation. Further studies characterizing a newly isolated cry mutant, crym, showed that the carboxyl-terminus of CRY is not necessary for CRY’s ability to impart photic information to the molecular clock. Instead, the C-terminus appears to be necessary for normal CRY stability and protein-protein interactions. Thus, we conclude that in contrast to previous reports on CRYs of other species, where the C-terminal domain was required for transduction of photic information, the C-terminus of DrosophilaCRY has a purely modulatory function.
During the second part of my dissertation work, I focused my studies on circadian thermoreception. While the effects of light in synchronization of the Drosophilaclock to environmental cycles have been extensively characterized, significantly less is known about temperature input pathways into the circadian pacemaker. I have used two approaches to look at how temperature affects the circadian system. First, I conducted a series of behavioral analyses looking at how locomotor rhythms can be phase-shifted in response to temperature cycles. By examining the behavior of genetically ablated flies, we determined that the well-characterized neurons controlling morning and evening surges of activity during light/dark cycles are also implicated in morning and evening behaviors under temperature cycles. However, we also find evidence of cells that contribute to modulating afternoon and evening behavior specifically under temperature cycles. These data contribute to a growing number of studies in the field suggesting that pacemaker cells may play different roles under various environmental conditions. Additionally, we provide data showing that intercellular communication plays an important role in regulating circadian response to temperature cycles. When the morning oscillator is absent or attenuated, the evening cells respond abnormally quickly to temperature cycles. My work thus provides information on the roles of different cell groups during temperature cycles, and suggests that beyond simply synchronizing individual oscillating cells, intercellular network activity may also have a role in modulating proper response to environmental time cues.
Finally, I present some preliminary work looking at effects of temperature on known circadian molecules. Using a combination of in vivo and cell culture techniques, I have found that TIM protein levels decrease at higher temperatures. My cell culture data suggest that this is a proteasome-independent degradation event. As TIM is also a key molecule in the light-input pathway, the stability of TIM proteins may be a key point of integration for light and temperature input pathways. While additional research needs to be conducted to confirm these effects in vivoin wild-type flies, these preliminary results identify a possible avenue for further study.
Taken together, my work has contributed new data on both molecular and neuronal substrates involved in processing light and temperature inputs into the Drosophila circadian clock.
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Restrição alimentar intra-uterina e suas repercussões sobre o desenvolvimento da termorregulação da prole / Maternal food restriction and its impact on offspring's development of thermoregulationSouza, Thais Ladeira Vieira de [UNIFESP] 29 April 2009 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:46Z (GMT). No. of bitstreams: 0
Previous issue date: 2009-04-29 / Introdução: Estudo previamente realizado em nosso laboratório demonstrou que a restrição alimentar intra-uterina (RAIU) provoca um retardo na termorregulação dos recém-nascidos. Em neonatos o tecido adiposo marrom (TAM) é essencial para a termogênese, principalmente devido à presença de proteínas desacopladoras (UCPs), cuja expressão pode ser modificada pela ação de hormônios como os hormônios da tireóide, a leptina e a insulina, que podem ser afetados pela restrição alimentar. A bomba de cálcio do retículo sarcoplasmático (SERCA1), presente no músculo e recentemente identificada no TAM, pode contribuir para a produção de calor. Objetivo: Avaliar a expressão das proteínas UCP1, UCP2, UCP3 e da SERCA1 no TAM e da UCP3 e da SERCA1 no músculo esquelético (ME) de animais submetidos a RAIU, bem como o perfil plasmático de insulina, leptina e hormônios tireoidianos destes filhotes. Métodos: Ratos fêmeas Wistar EPM-1 controle (C) receberam ração ad libitum durante todo o período gestacional e o grupo restrito (R) recebeu 50% desta quantidade. Quinze horas após o nascimento (pico de expressão das UCPs), os filhotes foram pesados e decapitados para coleta de sangue (pool) para a dosagem plasmática de insulina, leptina, T3 e T4 por ELISA. Foram coletados TAM e ME, para determinação da expressão das UCPs e da SERCA1 por imuno-histoquímica. Para análise dos resultados, utilizou-se o teste “t” de Student não pareado, com nível de significância de 5%. Resultados: Os animais R (n=16) apresentaram durante a gestação um ganho de peso corporal (g) significantemente inferior quando comparado ao C (n=16), (27,6 ± 3,8 e 109,0 ± 4,1). Os filhotes R (n=172) apresentaram redução significante do peso corporal (g) ao nascimento em relação aos filhotes C (n=169) (4,82 ± 0,05 e 5,83 ± 0,04); entretanto, não houve redução no número de filhotes por ninhada. A RAIU levou a um aumento significante na expressão (pixels) da UCP1 e da UCP2 no TAM da prole R em relação à prole C (em 42% e 53%, respectivamente). Não observamos diferença significante entre os grupos em relação à expressão da UCP3 e da SERCA1 no TAM e no ME. A concentração plasmática de insulina (ng/ml) foi significantemente maior nos filhotes R (n=8) em relação aos C (n=13) (3,34 ± 0,78 e 1,17 ± 0,18) e os níveis plasmáticos de T3 (ng/ml) foram significantemente menores nos filhotes R (n=10) quando comparados aos C (n=14) (0,82 ± 0,06 e 1,09 ± 0,08). Não houve diferenças significantes para as dosagens plasmáticas de leptina (pg/ml) (R (n=8) 987,79 ± 261,08 e C (n=11) 1255,54 ± 392,37) e T4 (ng/ml) (R (n=10) 20,99 ± 3,74 e C (n=12) 16,00 ± 1,68). Conclusão: O atraso no desenvolvimento da termorregulação previamente descritos nesses animais não parece resultar de redução na termogênese, mas de aumento na termólise, pois a RAIU provocou baixo peso dos filhotes ao nascimento, levando a uma maior relação superfície/ volume. A maior expressão da UCP1 e UCP2 no TAM observada nos filhotes restritos possivelmente ocorreu como um mecanismo compensatório para aumentar a termogênese, o que pode ter sido modulado por ação hormonal. / Background: Previous study from our laboratory has shown that intrauterine food restriction (IUFR) delayed thermoregulation of the newborns. In neonates brown adipose tissue (BAT) is essential for thermogenesis mainly due to the presence of uncoupling proteins (UCPs) and their expression can be modified by action of hormones such as thyroid hormone, leptin and insulin, which can be affected by food restriction. The sarcoplasmic reticulum Ca++ ATPase, (SERCA1) recently identified in BAT may contribute to heat production. Aim: The aim of this study was to evaluate the protein expression of UCP1, UCP2, UCP3 and SERCA1 in BAT and UCP3 and SERCA1 in skeletal muscle (SM) and the plasmatic concentration of insulin, leptin, T3 and T4 of newborn rats exposed to IUFR. Methods: Female Wistar EPM-1 control rats received chow ad libitum during pregnancy period (C) and food-restricted rats (R) received 50% of the amount ingested by C. Fifteen hours after birth, newborns were weighted and sacrificed by decapitation. Blood was collected for determination of insulin, leptin, T3 and T4 by ELISA. BAT and SM were used for determination of protein expression (UCPs and SERCA1) by immunohistochemistry. Unpaired Student’s t-test was used for statistical analysis of the results (p<0,05). Results: R animals (n=16) showed a significant lower weight gain (g) during pregnancy when compared to C (n=16) (27,6 ± 3,8 and 109,0 ± 4,1). R pups (n=172) showed a significant reduction in their body weight (g) at birth when compared to C (n=169) (4,82 ± 0,05 and 5,83 ± 0,04); however, there was no reduction in number of pups per litter. IUFR caused a significant increase in the expression (pixels) of UCP1 and UCP2 in BAT of the pups (42% and 53% respectively). UCP3 and SERCA1 expression in BAT and SM showed no significant differences between groups. Plasmatic insulin (ng/ml) was significantly higher in R pups (n=8) when compared to C (n=13) (3,34 ± 0,78 and 1,17 ± 0,18) and T3 levels (ng/ml) was significantly lower in R pups (n=10) when compared to C (n=14) (0,82 ± 0,06 and 1,09 ± 0,08). No differences between groups were found for leptin (pg/ml) (R (n=8) 987,79 ± 261,08 and C (n=11) 1255,54 ± 392,37) and T4 (ng/ml) levels (R (n=10) 20,99 ± 3,74 and C (n=12) 16,00 ± 1,68). Conclusion: The delay in development of thermoregulation previously described in these animals appears not to result from impairment in thermogenesis, but from an increase in heat loss, since IUFR caused low birth weight in pups, leading to greater surface/ volume ratio. The higher expression of UCP1 and UCP2 in BAT showed by R pups possibly occurred as a compensatory mechanism to increase thermogenesis, which may have been modulated by hormonal regulation. / TEDE / BV UNIFESP: Teses e dissertações
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Vybrané techniky monitorace v intenzivní péči v historickém kontextu / Selected technology monitoring in intesive care in a historical contextKNAJZLOVÁ, Petra January 2017 (has links)
The diploma thesis presents the development of selected monitoring techniques of basic life functions in historical continuity. From the measured variables, this work includes measurements of cardiac activity, blood pressure, pulse, respiration and body temperature of the adults patients with intensice care in a historical context. This is a theoretical diploma thesis, which is divided into several chapters describing the history of nursing, a view of the monitoring in intesive care in the historical context to the presents. The first part of this historical work describes the beginnings of nursing. Its own origin and development, until now. The prestige of the nurse´s profession is formed by the society. In the leading positions in medicine previously dominated the men, in nursing care mainly women. A balanced relationship between a nurse and a doctor has been and is very important. The next part is devoted to the development of intensive care and the development of the role of the nurse in these departmenst. The history of intensive care has led to new partnership relationships between physician and nurse. There was an unfamiliar environment in which critical patients had to be cared for. This new role for the sister led to the increase of copetencies, there was a need to increase the education activity that focused on intensive care area. The view of urgent condition has changed over time. Already in the early sources, the urgent condition was described as a condition in which the health and life of the affected person is urgently threatened. These urgent conditions gave rise to the first beds for intensive care. Futher, the development of all monitoring techniques to date, servise of the monitoring technology. The negatives associated with monitoring technology are described too. The thesis will be used as a preview of changing nursing care in the context of changes in monitoring techniques of the intensive care.
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Ecologia termal da jararaca-ilhoa, Bothrops insularis (Serpentes, Viperidae) : um estudo em condições naturais /Bovo, Rafael Parelli. January 2009 (has links)
Resumo: Dada a importância da temperatura na maior parte dos processos biológicos, estudos sobre a termorregulação têm desempenhado importante papel no entendimento sobre a ecologia dos vertebrados ectotérmicos. Em serpentes, como em outros ectotérmicos, o controle da temperatura corpórea (Tc) é dependente da utilização de fontes externas de calor e principalmente de ajustes comportamentais, embora ajustes fisiológicos e morfológicos também ocorram. Em geral, esse controle é alcançado por meio da escolha de ambientes quentes ou frios, cuja disponibilidade pode variar ao longo do dia e das estações do ano. A termorregulação, portanto, constitui aspecto central da biologia das serpentes, as quais dedicam porção considerável de seu tempo e energia a essa atividade. Os objetivos do presente estudo foram documentar a variação sazonal e circadiana da temperatura corpórea da jararaca-ilhoa, Bothrops insularis, em seu ambiente natural, a Ilha da Queimada Grande (IQG), a fim de prover análise descritiva da Tc e do comportamento termorregulatório destes animais à luz dos custos e benefícios da regulação da Tc na região tropical; e entender como estes parâmetros são ditados/influenciados por fatores ambientais (temperatura local e de microhábitats, umidade relativa, precipitação, radiação solar, vento, características do substrato) e bióticos (tamanho dos indivíduos, sexo, estágio reprodutivo, estado digestivo). (1) As jararacas-ilhoa são usualmente termoconformadoras, embora consigam atingir a temperatura corpórea preferida em todas as estações do ano; (2) as temperaturas ambientais indicam que a IQG é um ambiente termicamente favorável para essas serpentes; (3) a Tc destes animais sofre forte influência da variação sazonal e circadiana da temperatura ambientel... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Given the pervasive effects of temperature on most biological processes, studies focusing on thermoregulation are pivotal to the understanding of ectotherm's vertebrate ecology. In snakes, like other ectotherms, body temperature (Tb) control is dependent of external heat sources and based mainly on behavioral adjustments, although physiological and/or morphological adjustments can also occur. In general, such control is achieved through the choice of warm or cold environments, whose availability may vary along the days and/or seasons. Thus, thermoregulation can be regarded as a central aspect of snake biology, and these animals invest considerable time and energy into this activity. The aims of the present study were to document the seasonal and circadian variation in the Tb's of the golden lancehead, Bothrops insularis, in its natural habitat, the Queimada Grande Island (QGI). We then used such database to provide a descriptive analysis of Tb variation and thermoregulatory behavior for this species in the light of the costs-benefits theory applied to a tropical region. Our second goal was to understand how body temperature is dictated/influenced by environmental (local and microhabitat temperatures, relative humidity, precipitation, solar radiation, wind, substrate characteristics) and biotic factors (individual size, sex, reproductive stage, digestive state). The main findings of the present study were: (1) Golden lanceheads can be regarded as being thermoconformers, although they do reach their preferred body temperature in all seasons; (2) environmental temperatures indicate that QGI has a high thermal quality, i.e., it is thermically suitable for the snakes; (3) Tb is strongly influenced by seasonal and diel variation of the environmental temperature; (4) B. insularis selected... (Complete abstract click electronic access below) / Orientador: Otavio Augusto Vuolo Marques / Coorientador: Denis Otávio Vieira de Andrade / Banca: Ricardo Jannini Sawaya / Banca: Carlos Arturo Navas / Mestre
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Participação dos receptores opióides mu e kappa da substância cinzenta periaquedutal na febre induzida por estresse de contençãoSilva, Caroline Cristina 15 July 2016 (has links)
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Previous issue date: 2016-07-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The endogenous opioids are involved in analgesia, thermoregulation and physiological responses to various stressful stimuli such as infection, psychological stress and hypoxia. The mu and kappa receptors in the hypothalamus play a role in endotoxin-induced fever and hypoxia-induced anapyrexia (opposite response to fever), respectively. In addition, periaqueductal gray (PAG), which express both mu and kappa receptors, is involved in defence and thermoregulatory responses. Thus, our hypothesis is that mu and kappa opioid receptors in the PAG modulate the restraint-induced fever in rats by activating and inhibiting this response, respectively. To this end, body temperature (Tb) and heat loss index (HLI; inference for heat conservation/loss) and oxygen consumption (VO ; inference for thermogenesis) of unanesthetized Wistar rats submitted or not to restraint stress, was monitored before and after intra-PAG microinjection of the selective mu opioid receptor antagonist (CTAP; 1 and 10 μg/ 100 nL/ animal), the selective kappa-opioid receptor antagonist (nor-BNI; 1 and 4 μg/ 100 nL/ animal), or vehicle (saline; 100nL/ animal). CTAP and nor-BNI did not change the Tb or the HLI of the animals in euthermia. During the restraint stress, Tb increased in all groups of animals. However, this effect was significantly lower in animals treated with CTAP, and significantly higher in animals treated with nor-BNI. No treatment affected HLI, but CTAP decreased thermogenesis and nor-BNI increased thermogenesis. The results indicate that the mu and kappa opioid receptors in the PAG of rats play a pyrogenic and antipyretic role, respectively, during fever induced by restraint stress and these receptors in PAG may not be essential for the maintenance of Tb during euthermia. / Os opióides endógenos estão envolvidos na analgesia, termorregulação e respostas fisiológicas a vários estímulos estressantes, como infecção, estresse psicológico e hipóxia. Os receptores mu e kappa no hipotálamo desempenham um papel na febre induzida por endotoxina e anapirexia induzida por hipoxia (resposta oposta à febre), respectivamente. Além disso, a substância cinzenta periaquedutal (PAG), que expressa ambos os receptores mu e kappa, está envolvida na defesa e respostas de termorregulação. Assim, nossa hipótese é que os receptores opióides mu e kappa na PAG modulam a febre induzida por contenção em ratos, ativando e inibindo esta resposta, respectivamente. Para este fim, a temperatura corporal (Tc) e o índice de perda de calor (IPC; inferência para a conservação/perda de calor) e o consumo de oxigênio (VO ; inferência para a termogênese) de ratos Wistar não anestesiados submetidos ou não ao estresse contenção, foi monitorado antes e depois microinjeção intra-PAG do antagonista seletivo do receptor opióide mu (CTAP; 1 e 10 μg/ 100 nL/ animal), antagonista seletivo do receptor opióide kappa (nor-BNI; 1 e 4 μg/ 100 nL/ animal) ou veículo (solução salina; 100 nL / animal). A microinjeção de CTAP ou nor-BNI não alterou a Tc ou IPC dos animais em eutermia. Durante o estresse de contenção, a Tc aumentou em todos os grupos de animais. No entanto, este efeito foi significativamente menor no grupo de animais tratados com CTAP, e significativamente maior em animais tratados com nor-BNI. Nenhum tratamento afetou o IPC, mas o CTAP diminuiu a termogênese e o nor-BNI aumentou a termogênese. Os resultados indicam que os receptores opióides mu e kappa na PAG de ratos desempenham um papel pirogênico e antipirético, respectivamente, durante a febre induzida pelo estresse de contenção e estes receptores na PAG podem não ser essenciais para a manutenção de Tc durante eutermia.
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