Bibliografias temáticas / Rats Physiology

Literatura científica selecionada sobre o tema "Rats Physiology"

Autor: Grafiati

Publicado: 4 de junho de 2021

Última modificação: 20 de fevereiro de 2023

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Artigos de revistas sobre o assunto "Rats Physiology":

Barney, Christopher C. "Restrained rats and the observer effect in physiology". Experimental Physiology 96, n.º 12 (23 de novembro de 2011): 1253–54. http://dx.doi.org/10.1113/expphysiol.2011.061267.

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Musch, T. I., A. Bruno, G. E. Bradford, A. Vayonis e R. L. Moore. "Measurements of metabolic rate in rats: a comparison of techniques". Journal of Applied Physiology 65, n.º 2 (1 de agosto de 1988): 964–70. http://dx.doi.org/10.1152/jappl.1988.65.2.964.

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Two different open-circuit techniques of measuring metabolic rate were examined in rats at rest and during exercise. With one technique ambient air was drawn through a tightly fitting mask that was secured to the rat's head, whereas with the other technique the rat was placed into and ambient air was drawn through a Plexiglas box. Two series of experiments were performed. In series I, two groups were studied that consisted of rats that had received myocardial infarctions produced by coronary arterial ligations and rats that had received sham operations. In this series of experiments O2 uptake (VO2) and CO2 production (VCO2) were measured at rest, during four levels of submaximal exercise, and during maximal treadmill exercise in the same group of rats by use of both techniques in random order. VO2, VCO2, and the calculated respiratory exchange ratio (R) were similar at rest, during the highest level of submaximal exercise (20% grade, 37 m/min), and during maximal exercise; however, VO2 and VCO2 were significantly lower with the metabolic box technique compared with the mask technique during the three lowest work loads (5% grade, 19 m/min; 10% grade, 24 m/min; and 15% grade, 31 m/min). These differences appeared to be associated with a change in gait produced when the mask was worn. In series II, the arterial blood gas and acid-base responses to both submaximal and maximal exercise were measured using both techniques in a group of instrumented rats that had a catheter placed into the right carotid artery.(ABSTRACT TRUNCATED AT 250 WORDS)

Guerrero, Fr, e H. Burnet. "Effects of compression rate on rats carotid blood flow". Archives of Physiology and Biochemistry 103, n.º 2 (janeiro de 1995): 196–201. http://dx.doi.org/10.3109/13813459508996133.

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Sokoloff, Greta, Robert F. Kirby e Mark S. Blumberg. "Further evidence that BAT thermogenesis modulates cardiac rate in infant rats". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 274, n.º 6 (1 de junho de 1998): R1712—R1717. http://dx.doi.org/10.1152/ajpregu.1998.274.6.r1712.

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Previous research in infant rats suggested that brown adipose tissue (BAT), by providing warm blood to the heart during moderate cold exposure, protects cardiac rate. This protective role for BAT thermogenesis was examined further in the present study. In experiment 1, 1-wk-old rats in a warm environment were pretreated with saline or chlorisondamine (a ganglionic blocker), and then BAT thermogenesis was stimulated by injection with the β3-agonist CL-316243. In experiment 2, pups were pretreated with chlorisondamine and injected with CL-316243, and after BAT thermogenesis was stimulated the interscapular region of the pups was cooled externally with a thermode. In both experiments, cardiac rate, oxygen consumption, and physiological temperatures were monitored. Activation of BAT thermogenesis substantially increased cardiac rate in saline- and chlorisondamine-treated pups, and focal cooling of the interscapular region was sufficient to lower cardiac rate. The results of these studies support the hypothesis that BAT thermogenesis contributes directly to the modulation of cardiac rate.

Holloszy, John O. "Mortality rate and longevity of food-restricted exercising male rats: a reevaluation". Journal of Applied Physiology 82, n.º 2 (1 de fevereiro de 1997): 399–403. http://dx.doi.org/10.1152/jappl.1997.82.2.399.

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Holloszy, John O. Mortality rate and longevity of food-restricted exercising male rats: a reevaluation. J. Appl. Physiol. 82(2): 399–403, 1997.—Food restriction increases the maximal longevity of rats. Male rats do not increase their food intake to compensate for the increase in energy expenditure in response to exercise. However, a decrease in the availability of energy for growth and cell proliferation that induces an increase in maximal longevity in sedentary rats only results in an improvement in average survival, with no extension of maximal life span, when caused by exercise. In a previous study (J. O. Holloszy and K. B. Schechtman. J. Appl. Physiol. 70: 1529–1535, 1991), to test the possibility that exercise prevents the extension of life span by food restriction, wheel running and food restriction were combined. The food-restricted runners showed the same increase in maximal life span as food-restricted sedentary rats but had an increased mortality rate during the first one-half of their mortality curve. The purpose of the present study was to determine the pathological cause of this increased early mortality. However, in contrast to our previous results, the food-restricted wheel-running rats in this study showed no increase in early mortality, and their survival curves were virtually identical to those of sedentary animals that were food restricted so as to keep their body weights the same as those of the runners. Thus it is possible that the rats in the previous study had a health problem that had no effect on longevity except when both food restriction and exercise were superimposed on it. Possibly of interest in this regard, the rats in this study did considerably more voluntary running than those in the previous study. It is concluded that 1) moderate caloric restriction combined with exercise does not normally increase the early mortality rate in male rats, 2) exercise does not interfere with the extension of maximal life span by food restriction, and 3) the beneficial effects of food restriction and exercise on survival are not additive or synergistic.

Odenweller, C. M., C. T. Hsu, E. Sipe, J. P. Layshock, S. Varyani, R. L. Rosian e S. E. DiCarlo. "Laboratory exercise using "virtual rats" to teach endocrine physiology." Advances in Physiology Education 273, n.º 6 (dezembro de 1997): S24. http://dx.doi.org/10.1152/advances.1997.273.6.s24.

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Animal experimentation is limited in many curricula due to the expense, lack of adequate animal facilities and equipment, and limited experience of the teachers. There are also ethical concerns dealing with the comfort and safety of the animals. To overcome these obstacles, we developed a "dry laboratory" using "virtual rats." The "virtual rat" eliminates the obstacles inherent in animal experimentation, such as inadequate budgets, as well as avoiding important animal rights issues. Furthermore, no special materials are required for the completion of this exercise. Our goal in developing this dry laboratory was to create an experience that would provide students with an appreciation for the value of laboratory data collection and analysis. Students are exposed to the challenge of animal experimentation, experimental design, data collection, and analysis and interpretation without the issues surrounding the use of live animals.

Hofer, M. A. "Nutrient control of cardiac rate in infant rats: role of arterial baroreceptors". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 249, n.º 4 (1 de outubro de 1985): R443—R448. http://dx.doi.org/10.1152/ajpregu.1985.249.4.r443.

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A surgical procedure is described for the deafferentation of carotid sinus (CS) and aortic depressor (AD) baroreceptors in 2-wk suckling rats. Baroreflex testing in unanesthetized pups showed that cardiac rate responses to acute elevations of blood pressure were reduced to less than 9% of controls after combined denervation (CSAD), 28% after AD and 47% after CS denervation at 4 h. After 24 h of nutrient deprivation, resting cardiac rates of sham operated controls fell a mean of -148 beat/min, significantly more than CS, AD, or CSAD groups (P less than 0.01). Baroreflex test responses in individuals correlated significantly with their later responses to nutrient deprivation (r = 0.67, P less than 0.01). There were no significant differences in base-line cardiac rate, systolic blood pressure, or cardiac rate during 24 h intragastric milk infusion between deafferented and control pups. These experiments suggest that arterial baroreceptors are important in the cardiovascular adjustments after nutrient deprivation in suckling rats.

Holloszy, J. O., e E. K. Smith. "Longevity of cold-exposed rats: a reevaluation of the "rate-of-living theory"". Journal of Applied Physiology 61, n.º 5 (1 de novembro de 1986): 1656–60. http://dx.doi.org/10.1152/jappl.1986.61.5.1656.

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It has been postulated that increased energy expenditure results in shortened survival. To test this “rate-of-living theory” we examined the effect of raising energy expenditure by means of cold exposure on the longevity of rats. Male 6-mo-old SPF Long-Evans rats were gradually accustomed to immersion in cool water (23 degrees C). After 3 mo they were standing in the cool water for 4 h/day, 5 days/wk. They were maintained on this program until age 32 mo. The cold exposure resulted in a 44% increase in food intake (P less than 0.001). Despite their greater food intake, the cold-exposed rats' body weights were significantly lower than those of control animals from age 11 to 32 mo. The average age at death of the cold-exposed rats was 968 +/- 141 days compared with 923 +/- 159 days for the controls. The cold exposure appeared to protect against neoplasia, particularly sarcomas; only 24% of the necropsied cold-exposed rats had malignancies compared with 57% for the controls. The results of this study provide no support for the concept that increased energy expenditure decreases longevity.

Vitela, M., M. Herrera-Rosales, J. R. Haywood e S. W. Mifflin. "Baroreflex regulation of renal sympathetic nerve activity and heart rate in renal wrap hypertensive rats". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 288, n.º 4 (abril de 2005): R856—R862. http://dx.doi.org/10.1152/ajpregu.00620.2004.

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Despite its usefulness as a nongenetic model of hypertension, little information is available regarding baroreflex function in the Grollman, renal wrap model of hypertension in the rat. Baroreflex regulation of renal sympathetic nerve activity (RSNA) and heart rate (HR) were studied in male, Sprague-Dawley rats hypertensive (HT) for 1 or 4–6 wk after unilateral nephrectomy and figure-8 ligature around the remaining kidney or normotensive (NT) after sham surgery. Rats were anesthetized with Inactin and RSNA, and HR was recorded during intravenous infusions of sodium nitroprusside or phenylephrine to lower or raise mean arterial pressure (MAP). Response curves were analyzed using a logistic sigmoid function. In 1- and 4-wk HT rats the midpoints of RSNA and HR reflex curves were shifted to the right ( P < 0.05). Comparing NT to 1- or 4-wk HT rats, the gain of RSNA-MAP curves was no different; however, gain was reduced in the HR-MAP curves at both 1 and 4 wk in HT rats ( P < 0.05). In anesthetized rats the HR range was small; therefore, MAP and HR were measured in conscious rats during intravenous injections of three doses of phenylephrine and three doses of sodium nitroprusside. Linear regressions revealed a reduced slope in both 1- and 4-wk HT rats compared with NT rats ( P < 0.05). The results indicate that baroreflex curves are shifted to the right, to higher pressures, in hypertension. After 1–4 wk of hypertension the gain of baroreflex regulation of RSNA is not altered; however, the gain of HR regulation is reduced.

Jaldow, Eli J., e David A. OAkley. "Performance on a differential reinforcement of low-rate schedule in neodecorticated rats and rats with hippocampal lesions". Psychobiology 18, n.º 4 (dezembro de 1990): 394–403. http://dx.doi.org/10.3758/bf03333086.

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Mais fontes

Teses / dissertações sobre o assunto "Rats Physiology":

Hohl, Rodrigo. "Padronização de um modelo de indução de overreaching em ratos : desenvolvimento e perspectivas de investigação em natação e esteira". [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314733.

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Orientador: Denise Vaz de Macedo
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-08T20:10:55Z (GMT). No. of bitstreams: 1 Hohl_Rodrigo_D.pdf: 822844 bytes, checksum: fd38d4c98d17c89e25fcfd09540ba103 (MD5) Previous issue date: 2007
Resumo: O empirismo do treinamento pode levar a um desequilíbrio entre estímulo da atividade motora e tempo de recuperação do esforço. Como conseqüência o atleta pode experimentar um estado agudo de fadiga e queda de desempenho denominado de overreaching, revertido em poucos dias. A persistência desta situação de desequilíbrio pode levar a um quadro crônico de sensação de fadiga acompanhado de queda de desempenho denominado de síndrome do overtraining (OTS), que pode durar semanas ou meses. O objetivo deste trabalho foi padronizar um protocolo controlado e reprodutível de treinamento em ratos que contivesse um período de desequilíbrio entre o estímulo do exercício e o tempo de recuperação que gerasse queda de desempenho. Há duas formas de exercício em ratos amplamente utilizadas na literatura: a natação e a corrida em esteira. Os primeiros dois capítulos deste trabalho descrevem a padronização de um teste de desempenho em natação, reprodutível ao longo do crescimento animal, para ser utilizado em estudos longitudinais. Para isso, precisávamos considerar o empuxo sofrido pelo animal no meio líquido e validamos (Capítulo I) um aparato de medição de volume para animais vivos e conscientes (AMV). No capítulo II apresentamos os dados da comparação da reprodutibilidade de dois testes de desempenho até a exaustão na natação durante os cinco primeiros meses de vida dos ratos. Um teste com adição de cargas ajustadas de acordo com o porcentual da massa corporal (MC) e outro com cargas constantes (CC). Utilizando o AMV constatamos que a densidade dos animais não variava e, como conseqüência, o teste MC diminuía o tempo de exaustão conforme os ratos aumentavam a massa durante o crescimento, enquanto o teste CC mantinha o tempo de exaustão ao longo do tempo. Paralelamente, iniciamos os estudos com exercício em esteira. No Capítulo III apresentamos um protocolo de 11 semanas, onde o desequilíbrio entre exercício e recuperação foi determinado pelo aumento das sessões diárias nas três últimas semanas em 2, 3 e 4 vezes, com diminuição no tempo de recuperação entre elas. Selecionamos no final desse treinamento dois grupos de ratos, aqueles que apresentaram baixo desempenho (BD) e aqueles que apresentaram aumento ou manutenção do desempenho (AD). Embora ambos os grupos tenham apresentado uma diminuição da massa corporal durante o aumento da freqüência de treinamento, o grupo BD precisou de uma semana a mais de repouso para voltar a aumentar a massa, sem modificar o desempenho. No Capítulo IV comparamos quatro grupos de ratos obtidos desse protocolo (Controle (CO), Treinados (T), BD e AD) em análises no sangue (glutamina, glutamato, alanina e hemograma) e músculo (citrato sintase (CS), lactato desidrogenase e glicogênio). Comparando BD com T e AD observamos: (1) diminuição da concentração plasmática de glutamina e aumento na de glutamato, com valores semelhantes aos do grupo CO; (2) diminuição da capacidade oxidativa (CS) e manutenção dos estoques de glicogênio; (3) leucocitose. Em vista das diferenças encontrada entre os grupos BD e AD, concluímos que o protocolo de treinamento de indução de overreaching representa uma ferramenta metodológica importante, que pode auxiliar no desvendamento dos mecanismos causadores da queda de desempenho nos estados de overreaching/OTS
Abstract: The empirical training can lead to an imbalance between the motor activity stress and recovery. As consequence, the athlete can try an acute state of fatigue and performance decrement called overreaching, reverted in a few days. This continuous unbalance can lead to a chronic fatigue state called as overtraining syndrome (OTS), that may last weeks or months. Our goal was to standardize a controlled and reproducible training protocol in rats that contained an unbalance period between exercise stress and recovery with performance decrement. Two forms of exercise is widely used for rats training in literature: swimming and treadmill running. Chapters I and II describe an adequate standardization for workload in swimming tests when applied to longitudinal studies with sedentary rats. Therefore, considering the rats' buoyance, we validate (Chapter I) an apparatus for measuring conscientious living rat body volume (AMV). In chapter II, we evaluated two types of swimming tests with overload in sedentary rats: one with the load adjusted according to percentage of body weight (BW) and another one with constant load (CL) over time. Through the AMV, we found that the rats' density did not vary significantly, as consequence, MC test showed performance decrement as the rats had their mass increased, while CC test maintained performance along rats growth. In time, we initiate the studies with treadmill exercise. In Chapter III, we present an eleven weeks training protocol where the unbalance between exercise stress and recovery was determined by the increase of the daily sessions in 2, 3 and 4 times in the last three weeks, reducing the recovery time between sessions. We selected two groups of rats in the end of the training protocol, those that presented low performance (BD) and those that presented performance increase or maintenance (AD). Although both groups (AD and BD) showed corporal mass reduction during the increase of the daily frequency, BD group return to increase the mass one week later than AD group, without modifying the performance. In Chapter IV, we compare four groups of rats after the eleven weeks training protocol (Control (CO), Trained (T), AD and BD) in blood (glutamine, glutamate, alanine and hematological variables) and muscle analyses (citrate synthase (CS), lactate dehydrogenase and glycogen). Comparing BD with AD and T groups, we observe: (1) reduction of the glutamine plasma concentration and increase of glutamate, with similar CO values; (2) reduction of the oxidative capacity (CS) and maintenance of the glycogen stores; (3) leucocitosys. We conclude that the training protocol induces the rats to overreaching and it represents a relevant methodological tool in overreaching / OTS metabolical mechanisms research envolved in performance decrement
Doutorado
Fisiologia
Doutor em Biologia Funcional e Molecular

Feng, Tian Bin. "The effects of clomiphene citrate on ovarian function in rats". Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28984.

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In the present study, the effects of clomiphene citrate (CC) on ovulation, ovarian growth and ovarian steroidogenesis were examined. Ovulation in rats in response to PMSG was completely blocked by administration of three daily treatments of 1.0 mg CC/rat, but was restored by administration of hCG as a preovulatory LH surge substitute. When the number of treatment days was reduced to two days, 1.0 mg of CC enhanced ovulation in response to PMSG, whereas treatment for one day with the same dose of CC did not affect ovulation. The effects of CC on ovulation appear to be dose-dependent. The effects of CC on ovarian growth were similar to the effects of CC on ovulation. The ovarian growth induced by PMSG was inhibited by high doses of CC, while a lower dose had no effect. The inhibition of ovarian growth in terms of ovarian weight by a high dose of CC was restored by hCG given as a preovulatory LH surge. Treatment duration with CC appears to have an important influence on ovarian growth. Three daily treatments with high doses of CC significantly inhibited ovarian growth. However, when the number of treatment days was reduced from three to two, the opposite results were obtained in that CC significantly stimulated ovarian growth. The effects of CC on ovarian steroidogenesis in response to PMSG were dose-dependent. A higher dose of CC significantly stimulated estradiol-17β biosynthesis. Clomiphene citrate did not show any inhibitory effects on progesterone production. Progesterone production was stimulated by hCG in CC treated rats. Lower doses of CC stimulated progesterone and androgen production. Further studies on this are necessary. Histological examination of the ovary revealed that CC selectively inhibited the development of nondominant follicles. The dominant follicles were unaffected as for they were able to develop to the mature stage. These results suggest that the effects of CC on ovulation, ovarian growth and ovarian steroidogenesis are dose-dependent and affected by treatment duration. Clomiphene citrate is assumed to exert its action via a gonadotropic mechanism.
Medicine, Faculty of
Obstetrics and Gynaecology, Department of
Graduate

Chura, Lindsay R. "The effect of chronic and acute maternal stress on expression of placental barrier genes in the rat /". Connect to online version, 2006. http://ada.mtholyoke.edu/setr/websrc/pdfs/mhc/2006/143.pdf.

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Van, Wageningen Gerhard Derek. "The crossed mesostriatal pathway and circling behaviour in rats". Master's thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/21152.

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Bibliography: pages 326-345.
Rats with unilateral 6-OHDA lesions of the nigrostriatal (NS) projection display motor asymmetry in the form of rotational behaviour. The rotation is in the direction ipsilateral with respect to the lesioned side (Ungerstedt 1979). The nett ipsilateral rotations decrease with time, from 1 week to about a month. This decrease has been interpreted as recovery from the lesion-induced motor asymmetry (Glick and Cox 1978). Pritzel et al. (1983) have ascribed the recovery from motor asymmetry to increased activity of a crossed NS projection, which is spared by the ipsilateral lesion. The present study has defined the size and anatomical path of this crossed projection, and has examined its involvement in the behavioural recovery of rats from lesion-induced motor asymmetry. The anatomy of the crossed projection was investigated in male Long-Evans rats using retrograde HRP tract tracing from deposition sites in the striatum.

Lee, Ronald Duane. "The synthesis of 2-((E)-1'-propenyl)-(E)-2-pentenoic acid and its metabolism and pharmacokinetics in rats". Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26437.

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The anticonvulsant drug valproic acid (VPA) is extensively metabolized with 16 metabolites identified in man. Of interest are the unsaturated metabolites which appear to be responsible for the observed secondary antiepileptic activity and/or idiosyncratic hepatotoxicity. A study by Abbott et al . (1986) has shown 2-((E)-1'-propenyl)-(E)-2-pentenoic acid ((E,E)-2,3'-diene VPA) to be a major unsaturated metabolite of VPA. Acheampong (1985) demonstrated that an isomeric mixture of 2,3'-diene VPA prevented pentylenetetrazole-induced seizures in mice and had 60% the potency of VPA. Research on (E,E)-2,3'-diene VPA is limited even though the diene appears to be a contributor to the secondary antiepileptic effect. Available synthesis of 2,3'-diene VPA result in two or more isomers with very low yields as shown by Acheampong and Abbott (1985). The object of this work was, therefore, to synthesize (E,E)-2,3'-diene VPA in sufficient quantity and isomeric purity for metabolic and pharmacokinetic studies in rats. Synthesis of (E,E)-2,3'-diene VPA was achieved by the alkylation of ethyl (Z)-2-pentenoate to afford ethyl 2-(l'-hydroxypropyl)-(E)-2-pentenoate. Dehydration using methanesulfonyl chloride and potassium hydride gave the ethyl ester of (E,E)-2,3'-diene VPA. Hydrolysis of the ester in 1 N NaOH afforded an 81.2% pure sample of (E,E)- 2,3'-diene VPA as determined by GCMS and NMR. A second method was used to unequivocally synthesize (E,E)-2,3' - diene VPA whereby an O-trimethylsilylketene acetal was oxidized via a hydride abstractor to yield two isomers of 2,3'-diene VPA plus the starting material (E)-3-ene VPA. The identity of the products were determined by GCMS with the major isomer being (E,E)-2,3'-diene VPA. In the metabolism studies, Wistar rats were given 100 mg/kg i.p. of (E,E)-2,3'-diene VPA and bile and urine collected for 24 hours. GCMS analysis revealed three metabolites present in both bile and urine. These were reduction products of (E,E)-2,3'-diene VPA metabolism and consisted of the monounsatured (E)-3-ene VPA and (E)-2-ene VPA plus the fully saturated VPA. These results suggest that trace levels of (E)-3-ene VPA observed after VPA dosing may not be a direct metabolic product of VPA itself but rather a reduced metabolite of (E,E)-2,3'-diene VPA. All polar metabolites are yet to be identified. For the pharmacokinetic studies, two doses, 20 and 100 mg/kg of (E,E)-2,3'-diene VPA were administered i.v. to Wistar rats and the plasma concentration vs time decline curve determined using GCMS analysis of the plasma samples. The bile duct of these animals was then cannulated and the study repeated. A comparison between the elimination rate constant (KE), clearance (C1), and volume of distribution (Vd) between the bile duct intact and cannulated rats for both dose groups revealed no significant differences (p>0.1). A comparison of the KE, Vd, and C1 between dosage groups of both bile duct intact and cannulated rats revealed no significant difference (p>0.08-0.7). Therefore, extensive enterohepatic recirculation was not apparent and the elimination of (E,E)-2,3'-diene VPA appeared to be dose-independent. The diene seems to follow a simple one-compartment model with a half-life of 35.9±8.9 (S.D.) minutes and a large volume of distribution of 0.95±0.22 (S.D.) L/kg. In vitro protein binding studies revealed that (E,E)-2,3'-diene VPA saturates plasma proteins between concentrations of 30 - 600 ug/mL. The percent of (E,E)-2,3'-diene VPA bound decreases from 92.1% to 28.7% as the concentration of diene increases suggesting concentration-dependent protein binding. The synthesis of (E,E)-2,3'-diene VPA in substantial quantities has allowed metabolic and pharmacokinetic studies to be performed in rats. Preliminary studies showed that (E,E)-2,3' -diene VPA was metabolically reduced to monounsaturated and saturated products. Pharmacokinetic data appear to indicate a potential for the diene to accumulate in the central nervous system. Further studies are required to determine the contribution of (E,E)-2,3'-diene VPA to the secondary antiepileptic activity of VPA.
Pharmaceutical Sciences, Faculty of
Graduate

Anand, Uma. "Target derived influences on primary afferent neurons in rats". Thesis, King's College London (University of London), 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283305.

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Walker, Celia Gillian Rowena. "Dietary and metabolic regulation of leptin in rats". Thesis, The University of Sydney, 2005. https://hdl.handle.net/2123/28031.

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Obesity has become one of the most prevalent health concerns of developed countries. Consequently metabolic research in recent years has focussed on the control of body weight, causes of obesity, and possible preventative measures. Body weight is usually maintained through a series of hormonal and neuronal actions which respond to changes in energy balance. The adipose tissue hormone leptin plays an important role in the regulation of body weight, by decreasing appetite and increasing energy expenditure through a number of central and peripheral effects. Basal leptin levels are raised proportionately to adiposity but leptin levels are also acutely altered by nutritional state. Because of the importance of this hormone in body weight homeostasis it is necessary to understand how it is regulated.

Courtois, Frédérique J. "Residual erectile capacity of paraplegic rats". Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74335.

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This series of studies was designed to investigate the residual erectile capacity of paraplegic rats. Results from human studies suggest that erectile capacity in paraplegic men may be maintained following psychogenic, but not reflexogenic, stimulation. Using an animal model to overcome methodological difficulties associated with human studies, reflexogenic stimulation was defined as local stimulation of the genitals, and psychogenic stimulation as stimulation of a key central structure. Results from higher CNS stimulation showed that electrical stimulation of the medial preoptic area of the hypothalamus reliably triggers penile responses in rats and elicits penile responses as a post-stimulation effect. Optimal stimulation parameters were identified and used to maximize the effect on spinal animals. The effect of central stimulation was then compared to that of local stimulation to examine whether truly sexual responses were elicited. Results demonstrated that central stimulation elicits primarily erectile responses with a few urine-marking responses. The two stimulation sources were then used to test the residual erectile capacity of paraplegic rats whose lesions interrupted the L6-S1 fibers. Results showed that a high proportion of animals (85%) indeed maintain erectile responses to central stimulation but lose reflex activity from the genital area. These results support the hypothesis under study and are discussed in terms of the neural substrates of erection and their implication at the human level.

Andalib, Ali. "Relationship between a trial fibrillation and hypertension in rats". Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=83962.

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The importance of hypertension as a risk factor for the development of AF is well recognized. Despite this leading importance, the role of essential hypertension in providing a substrate for AF is incompletely understood. The present study was undertaken to investigate the possibility of having rats as an adequate animal model for the relationship between hypertension and AF in man and to elucidate the role of hypertension as a risk factor for AF. The results of this study show that structural remodeling especially in the form of increased amount of interstitial fibrosis seems to be the major contributing factor to the AF sustainability. Although it can be concluded that hypertension could accelerate the accumulation of fibrosis which occurs during the normal process of aging, a clear relationship between hypertension and AF in this rat model was not found. Further work in the other animal models of hypertension would be interesting.

Amoni, Matthew. "The effects of magnesium treatment on short-term changes in heart rate variability, ventricular function and lipid profile in streptozotocin-induced diabetic rats". Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/24459.

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INTRODUCTION: Diabetes mellitus is a major and rapidly growing worldwide health problem, causing mortality largely in developing countries such as South Africa. Diabetes induces life threatening cardiovascular complications including cardiac autonomic neuropathy, ventricular dysfunction and dyslipidaemia, which are dependent on the duration and severity of the diabetes. Most complications are identified at a late, irreversible stage following long-standing diabetes; therefore, early detection and treatment of cardiovascular complications may reverse impairments and improve outcomes. The early treatment of diabetic complications remains ineffective, as the associated underlying features, such as electrolyte disturbances, are poorly understood. A key electrolyte disturbance in diabetes is hypomagnesaemia, which is also an independent cardiovascular risk factor. However, the effects of magnesium (Mg²⁺) supplementation are unclear. Therefore, this study investigated the effects of Mg²⁺ treatment on the early manifestations of streptozotocin (STZ)-induced diabetic cardiac complications. METHODS: Adult male Wistar rats were treated once with STZ (50 mg/kg, i.p.) or vehicle (citrate), and daily for seven days with MgSO4 (270 mg/kg, i.p.) or saline. Blood glucose and body weight were monitored daily. On the eighth day, in vivo tail-pulse plethysmography was recorded for analysis of heart rate variability (HRV), a marker of cardiac autonomic function. Ex vivo, Langendorff-based left ventricular (LV) pressure-volume parameters were measured using an intraventricular balloon. Other hearts were stained with Masson's trichrome and haematoxylin and eosin for histological analysis. Cardiac tissue Mg²⁺ concentration as well as plasma lipid- and Mg²⁺ levels were measured by colorimetric assays. RESULTS: Diabetes reduced heart rate and increased the low-frequency (LF)/high-frequency (HF) power ratio. Mg²⁺ treatment prevented theses diabetes-induced changes in heart rate and in the low-frequency (LF)/high-frequency (HF) power ratio (p < 0.05, n = 9/group). In addition, Mg²⁺ restored orthostatic stress induced changes in heart rate, and LF/HF ratio in diabetic rats (p < 0.05, n = 9/group). In isolated hearts, Mg²⁺ reversed the diabetes-induced decrease in LV end-diastolic elastance (p < 0.05, n = 6/group) and the right shift of end diastolic equilibrium volume intercept from 49 ± 6 μ L to 25 ± 5 μL (p < 0.05, n = 6/group), without altering LV developed pressure or end systolic elastance. Diabetes significantly increased plasma triglyceride, total cholesterol and blood glucose (p < 0.05, n = 7/group), and significantly decreased body weight (p < 0.05, n ≥ 16/group) compared to control, but these changes were not prevented by Mg²⁺ treatment. Neither diabetes nor Mg²⁺ treatment altered plasma- and tissue Mg²⁺ levels. Histologically, diabetes and Mg²⁺ treatment also did not alter cardiomyocyte size or the amount of interstitial collagen in myocardial tissue. CONCLUSION: These results show that Mg²⁺ treatment attenuates diabetes-induced autonomic dysfunction and improves LV diastolic distensibility in short-term diabetes. However, the diabetic metabolic disturbances of hyperglycaemia and dyslipidaemia, the changes in cardiac microstructure or the plasma- and cardiac tissue Mg²⁺ levels were uninfluenced by Mg²⁺ treatment. This suggests that Mg²⁺ exerted its beneficial effects independent of these factors, highlighting the underling mechanisms remain to be clarified. The Mg²⁺ levels not measured in this study by which changes could have been mediated was intracellularly; an aspect that should be further explored in future studies. Furthermore, whether these effects would be translatable to chronic diabetes is an important next question. Thus, the results of this study suggest that Mg²⁺ may have a modulatory role in treating early diabetic cardiovascular complications, but future studies will need to clarify the underlying mechanisms.

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Livros sobre o assunto "Rats Physiology":

1947-, Kolb Bryan, e Tees Richard C, eds. The Cerebral cortex of the rat. Cambridge, Mass: MIT Press, 1990.

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Elger, M. The vascular pole of the renal glomerulus of rat. Berlin: Springer, 1998.

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Zilles, Karl. The cortex of the rat: A stereotaxic atlas. Berlin: Springer-Verlag, 1985.

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Everett, John W. Neurobiology of reproduction in the female rat: A fifty-year perspective. Berlin: Springer-Verlag, 1989.

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Altman, Joseph. Atlas of prenatal rat brain development. Boca Raton, Fla: CRC Press, 1995.

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Semagin, Vladlen Nikolaevich. Tip nervnoĭ sistemy: Stressoustoĭchivostʹ i reproduktivnai͡a︡ funkt͡s︡ii͡a︡. Moskva: "Nauka", 1988.

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Wingerd, Bruce D. Rat dissection manual. Burlington, N.C: Carolina Biological Supply, 1988.

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Alvarez-Bolado, G. Developmental brain maps: Structure of the embryonic rat brain. New York: Elsevier, 1996.

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Cassella, J. P. The rat nervous system: An introduction to preparatory techniques. Chichester: J. Wiley, 1997.

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E. A. J. F. Lakke. The projections to the spinal cord of the rat during development: A time-table of descent. Berlin: Springer, 1997.

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Capítulos de livros sobre o assunto "Rats Physiology":

Borbély, Alexander A., Peter Achermann, Lorenz Trachsel e Irene Tobler. "Sleep Homeostasis in Humans and Rats". In Clinical Physiology of Sleep, 191–98. New York, NY: Springer New York, 1988. http://dx.doi.org/10.1007/978-1-4614-7599-6_13.

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Pohl, M., P. Mareš, L. Velíšek e L. Stanková. "Motor Seizures in Immature Rats". In Physiology, Pharmacology and Development of Epileptogenic Phenomena, 179–81. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-46732-5_41.

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Kehoe, Priscilla, e Elliott M. Blass. "Behavioral Responsivity to Tastes in Developing Rats". In The Physiology of Thirst and Sodium Appetite, 25–29. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4757-0366-5_5.

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Moe, Karen. "The Ontogeny of Salt Intake in Rats". In The Physiology of Thirst and Sodium Appetite, 31–36. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4757-0366-5_6.

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de Caro, G., e L. G. Micossi. "Selective Antidipsogenic Effect of Kassinin in Wistar Rats". In The Physiology of Thirst and Sodium Appetite, 245–49. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4757-0366-5_32.

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Blass, Elliott M. "The Ontogeny of Thirst Mechanisms in Albino Rats". In The Physiology of Thirst and Sodium Appetite, 19–24. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4757-0366-5_4.

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Kraly, F. Scott. "Disorderly Drinking During Development in Spontaneously Hypertensive Rats". In The Physiology of Thirst and Sodium Appetite, 541–45. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4757-0366-5_72.

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Desrayaud, Sandrine, e Michel Lemaire. "Brain Penetration of SDZ PSC 833 in Rats". In Biology and Physiology of the Blood-Brain Barrier, 197–204. Boston, MA: Springer US, 1996. http://dx.doi.org/10.1007/978-1-4757-9489-2_33.

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Mueli, Christian, e Georges Peters. "The Nature of the Salt Appetite of Adrenalectomized Rats". In The Physiology of Thirst and Sodium Appetite, 465–72. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4757-0366-5_61.

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Schulkin, Jay. "Behavioral Dynamics in the Appetite for Salt in Rats". In The Physiology of Thirst and Sodium Appetite, 497–502. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4757-0366-5_66.

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Trabalhos de conferências sobre o assunto "Rats Physiology":

Arum Cahyaning Putri, Eka, Raden Argarini, Bambang Purwanto e Lilik Herawati. "Intermittent Physical Training Decreases Peak of Blood Glucose Level after Meals in Rats". In Surabaya International Physiology Seminar. SCITEPRESS - Science and Technology Publications, 2017. http://dx.doi.org/10.5220/0007333100760079.

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Nafi'ah, Imelda Rosalyn Sianipar, Nurul Paramita, Rabia e Neng Tine Kartinah. "Fgf 21 Secretion as Acute Response to Exercise in High Fat Diet Fed Rats". In Surabaya International Physiology Seminar. SCITEPRESS - Science and Technology Publications, 2017. http://dx.doi.org/10.5220/0007336002080211.

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Hartini Yuliawati, Tri, Dewi Ratna Sari, Rimbun, Atika, Iskantijah e Ari Gunawan. "Effect of Exhaustive Exercise on Blood Lymphocyte Count and Diameter of Splenic White Pulp in Rats". In Surabaya International Physiology Seminar. SCITEPRESS - Science and Technology Publications, 2017. http://dx.doi.org/10.5220/0007338102980303.

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Rambung, Etha, Viskasari P. Kalanjati e Abdurachman. "Aluminum Foil Shield Diminishes the Electromagnetic Radiation of Mobile Phones in the Cerebellum of Adult Male Rats". In Surabaya International Physiology Seminar. SCITEPRESS - Science and Technology Publications, 2017. http://dx.doi.org/10.5220/0007333500970100.

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Pamungkas Wicaksono, Faris, Sugiharto, Rias Gesang Kinanti, Paulus Liben, Suhartono Taat Putra e Purwo Sri Rejeki. "Impact of Music on Sport Intensity (Allegro) and on Levels of Left Ventricular Myocardial Damage in Wistar Rats". In Surabaya International Physiology Seminar. SCITEPRESS - Science and Technology Publications, 2017. http://dx.doi.org/10.5220/0007339403780382.

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Mahruzza Putri, Elyna, Achadiyani, Sunarjati, Sudigdoadi, Oki Suwarsa e Adi Santosa Maliki. "The Effect of Cantaloupe Extract on Sperm Quality of Adult White Rats (Rattus Novergicus) Strain Induced by Ciproteron Acetat". In Surabaya International Physiology Seminar. SCITEPRESS - Science and Technology Publications, 2017. http://dx.doi.org/10.5220/0007333200800083.

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Wanito Wigati, Kristanti, Sundari Indah Wiyasihati e Misbakhul Munir. "Low, Moderate, and High Intensity Swimming Exercise Has No Negative Effect on Semen Analysis Test in Male Wistar Rats". In Surabaya International Physiology Seminar. SCITEPRESS - Science and Technology Publications, 2017. http://dx.doi.org/10.5220/0007334901650168.

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Sukirno, Herlia Elvita, Mohammad Zulkarnain e Rostika Flora. "Correlation Between Oxidative Stress Level with Plasma Beta Endorphin Level of Male Laboratory Rats Given Aerobic and Anaerobic Exercise". In Surabaya International Physiology Seminar. SCITEPRESS - Science and Technology Publications, 2017. http://dx.doi.org/10.5220/0007337402710276.

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Flora, Rostika, Lisna Ferta Sari, Muhammad Zulkarnain e Sukirno. "The Difference of B-Endorfin Level in Brain Tissue and Testicular Tissue on Wistar Rats Given Once a Week Aerobic and Anaerobic Exercise". In Surabaya International Physiology Seminar. SCITEPRESS - Science and Technology Publications, 2017. http://dx.doi.org/10.5220/0007337102560260.

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K. Dharmawan, Dion, Viskasari P. Kalanjati e Abdurachman. "The Effect of an Aluminium Foil Shield on Reducing The Strength of Electromagnetic Radiation of Mobile Phones Reaching the Oculi of Adult Male Rats". In Surabaya International Physiology Seminar. SCITEPRESS - Science and Technology Publications, 2017. http://dx.doi.org/10.5220/0007332900670071.

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Relatórios de organizações sobre o assunto "Rats Physiology":

Chang, Min Cheol, Yoo Jin Choo e Sohyun Kim. Effect of Prehabilitation for Patients with Frailty Undergoing Colorectal Cancer Surgery: A Systematic Review and Meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, novembro de 2022. http://dx.doi.org/10.37766/inplasy2022.11.0105.

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Review question / Objective: We performed a meta-analysis to assess the impact of prehabilitation before colorectal surgery on functional outcome and postoperative complications in patients with frailty. Condition being studied: Colorectal cancer is a common disease in the elderly, and over 65 years of age accounts for more than 50% of all patients with colorectal cancer. The patients with colorectal cancer surgery showed 8.7% major morbidity and mortality and 31.6% minor complications. The high complication rate of patients with colorectal surgery is related to the fact that there are many elderly patients. Frailty is common in elderly patients, and the frailty is associated with adverse perioperative outcomes. The frail patients with colorectal surgery showed worse postoperative morbidity, mortality and prolonged length of hospital stay. Although the frailty results from irresistible aging-associated decline in reserve and function across multiple physiologic systems, several attempts have been conducted to improve frailty in patients with colorectal cancer surgery and consequently improve the postoperative outcomes. Prehabilitation was one of these attempts for improving physical activity and postoperative outcomes on patients with frailty undergoing colorectal cancer surgery. So far, several studies conducted clinical trials for determining whether prehabilitation has positive effect on improving postoperative outcomes in patients with frailty undergoing colorectal surgery. However, the results of these previous studies are controversial.

Brosh, Arieh, David Robertshaw, Yoav Aharoni, Zvi Holzer, Mario Gutman e Amichai Arieli. Estimation of Energy Expenditure of Free Living and Growing Domesticated Ruminants by Heart Rate Measurement. United States Department of Agriculture, abril de 2002. http://dx.doi.org/10.32747/2002.7580685.bard.

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Research objectives were: 1) To study the effect of diet energy density, level of exercise, thermal conditions and reproductive state on cardiovascular function as it relates to oxygen (O2) mobilization. 2) To validate the use of heart rate (HR) to predict energy expenditure (EE) of ruminants, by measuring and calculating the energy balance components at different productive and reproductive states. 3) To validate the use of HR to identify changes in the metabolizable energy (ME) and ME intake (MEI) of grazing ruminants. Background: The development of an effective method for the measurement of EE is essential for understanding the management of both grazing and confined feedlot animals. The use of HR as a method of estimating EE in free-ranging large ruminants has been limited by the availability of suitable field monitoring equipment and by the absence of empirical understanding of the relationship between cardiac function and metabolic rate. Recent developments in microelectronics provide a good opportunity to use small HR devices to monitor free-range animals. The estimation of O2 uptake (VO2) of animals from their HR has to be based upon a consistent relationship between HR and VO2. The question as to whether, or to what extent, feeding level, environmental conditions and reproductive state affect such a relationship is still unanswered. Studies on the basic physiology of O2 mobilization (in USA) and field and feedlot-based investigations (in Israel) covered a , variety of conditions in order to investigate the possibilities of using HR to estimate EE. In USA the physiological studies conducted using animals with implanted flow probes, show that: I) although stroke volume decreases during intense exercise, VO2 per one heart beat per kgBW0.75 (O2 Pulse, O2P) actually increases and measurement of EE by HR and constant O2P may underestimate VO2unless the slope of the regression relating to heart rate and VO2 is also determined, 2) alterations in VO2 associated with the level of feeding and the effects of feeding itself have no effect on O2P, 3) both pregnancy and lactation may increase blood volume, especially lactation; but they have no effect on O2P, 4) ambient temperature in the range of 15 to 25°C in the resting animal has no effect on O2P, and 5) severe heat stress, induced by exercise, elevates body temperature to a sufficient extent that 14% of cardiac output may be required to dissipate the heat generated by exercise rather than for O2 transport. However, this is an unusual situation and its affect on EE estimation in a freely grazing animal, especially when heart rate is monitored over several days, is minor. In Israel three experiments were carried out in the hot summer to define changes in O2P attributable to changes in the time of day or In the heat load. The animals used were lambs and young calves in the growing phase and highly yielding dairy cows. In the growing animals the time of day, or the heat load, affected HR and VO2, but had no effect on O2P. On the other hand, the O2P measured in lactating cows was affected by the heat load; this is similar to the finding in the USA study of sheep. Energy balance trials were conducted to compare MEI recovery by the retained energy (RE) and by EE as measured by HR and O2P. The trial hypothesis was that if HR reliably estimated EE, the MEI proportion to (EE+RE) would not be significantly different from 1.0. Beef cows along a year of their reproductive cycle and growing lambs were used. The MEI recoveries of both trials were not significantly different from 1.0, 1.062+0.026 and 0.957+0.024 respectively. The cows' reproductive state did not affect the O2P, which is similar to the finding in the USA study. Pasture ME content and animal variables such as HR, VO2, O2P and EE of cows on grazing and in confinement were measured throughout three years under twenty-nine combinations of herbage quality and cows' reproductive state. In twelve grazing states, individual faecal output (FO) was measured and MEI was calculated. Regression analyses of the EE and RE dependent on MEI were highly significant (P<0.001). The predicted values of EE at zero intake (78 kcal/kgBW0.75), were similar to those estimated by NRC (1984). The EE at maintenance condition of the grazing cows (EE=MEI, 125 kcal/kgBW0.75) which are in the range of 96.1 to 125.5 as presented by NRC (1996 pp 6-7) for beef cows. Average daily HR and EE were significantly increased by lactation, P<0.001 and P<0.02 respectively. Grazing ME significantly increased HR and EE, P<0.001 and P<0.00l respectively. In contradiction to the finding in confined ewes and cows, the O2P of the grazing cows was significantly affected by the combined treatments (P<0.00l ); this effect was significantly related to the diet ME (P<0.00l ) and consequently to the MEI (P<0.03). Grazing significantly increased O2P compared to confinement. So, when EE of grazing animals during a certain season of the year is estimated using the HR method, the O2P must be re measured whenever grazing ME changes. A high correlation (R2>0.96) of group average EE and of HR dependency on MEI was also found in confined cows, which were fed six different diets and in growing lambs on three diets. In conclusion, the studies conducted in USA and in Israel investigated in depth the physiological mechanisms of cardiovascular and O2 mobilization, and went on to investigate a wide variety of ruminant species, ages, reproductive states, diets ME, time of intake and time of day, and compared these variables under grazing and confinement conditions. From these combined studies we can conclude that EE can be determined from HR measurements during several days, multiplied by O2P measured over a short period of time (10-15 min). The study showed that RE could be determined during the growing phase without slaughtering. In the near future the development microelectronic devices will enable wide use of the HR method to determine EE and energy balance. It will open new scopes of physiological and agricultural research with minimizes strain on animals. The method also has a high potential as a tool for herd management.

Harman, Gary E., e Ilan Chet. Enhancement of plant disease resistance and productivity through use of root symbiotic fungi. United States Department of Agriculture, julho de 2008. http://dx.doi.org/10.32747/2008.7695588.bard.

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The objectives of the project were to (a) compare effects ofT22 and T-203 on growth promotion and induced resistance of maize inbred line Mol7; (b) follow induced resistance of pathogenesis-related proteins through changes in gene expression with a root and foliar pathogen in the presence or absence of T22 or T-203 and (c) to follow changes in the proteome of Mol? over time in roots and leaves in the presence or absence of T22 or T-203. The research built changes in our concepts regarding the effects of Trichoderma on plants; we hypothesized that there would be major changes in the physiology of plants and these would be reflected in changes in the plant proteome as a consequence of root infection by Trichoderma spp. Further, Trichoderma spp. differ in their effects on plants and these changes are largely a consequence of the production of different elicitors of elicitor mixtures that are produced in the zone of communication that is established by root infection by Trichoderma spp. In this work, we demonstrated that both T22 and T-203 increase growth and induce resistance to pathogens in maize. In Israel, it was shown that a hydrophobin is critical for root colonization by Trichoderma strains, and that peptaibols and an expansin-like protein from Ttrichoderma probably act as elicitors of induced resistance in plants. Further, this fungus induces the jasmonate/ethylene pathway of disease resistance and a specific cucumber MAPK is required for transduction of the resistance signal. This is the first such gene known to be induced by fungal systems. In the USA, extensive proteomic analyses of maize demonstrated a number of proteins are differentially regulated by T. harzianum strain T22. The pattern of up-regulation strongly supports the contention that this fungus induces increases in plant disease resistance, respiratory rates and photosynthesis. These are all very consistent with the observations of effects of the fungus on plants in the greenhouse and field. In addition, the chitinolytic complex of maize was examined. The numbers of maize genes encoding these enzymes was increased about 3-fold and their locations on maize chromosomes determined by sequence identification in specific BAC libraries on the web. One of the chitinolytic enzymes was determined to be a heterodimer between a specific exochitinase and different endochitinases dependent upon tissue differences (shoot or root) and the presence or absence of T. harzianum. These heterodimers, which were discovered in this work, are very strongly antifungal, especially the one from shoots in the presence of the biocontrol fungus. Finally, RNA was isolated from plants at Cornell and sent to Israel for transcriptome assessment using Affymetrix chips (the chips became available for maize at the end of the project). The data was sent back to Cornell for bioinformatic analyses and found, in large sense, to be consistent with the proteomic data. The final assessment of this data is just now possible since the full annotation of the sequences in the maize Affy chips is just now available. This work is already being used to discover more effective strains of Trichoderma. It also is expected to elucidate how we may be able to manipulate and breed plants for greater disease resistance, enhanced growth and yield and similar goals. This will be possible since the changes in gene and protein expression that lead to better plant performance can be elucidated by following changes induced by Trichoderma strains. The work was in, some parts, collaborative but in others, most specifically transcriptome analyses, fully synergistic.

Sherman, Amir, Rebecca Grumet, Ron Ophir, Nurit Katzir e Yiqun Weng. Whole genome approach for genetic analysis in cucumber: Fruit size as a test case. United States Department of Agriculture, dezembro de 2013. http://dx.doi.org/10.32747/2013.7594399.bard.

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The Cucurbitaceae family includes a broad array of economically and nutritionally important crop species that are consumed as vegetables, staple starches and desserts. Fruit of these species, and types within species, exhibit extensive diversity as evidenced by variation in size, shape, color, flavor, and others. Fruit size and shape are critical quality determinants that delineate uses and market classes and are key traits under selection in breeding programs. However, the underlying genetic bases for variation in fruit size remain to be determined. A few species the Cucurbitaceae family were sequenced during the time of this project (cucumber was already sequenced when the project started watermelon and melon sequence became available during the project) but functional genomic tools are still missing. This research program had three major goals: 1. Develop whole genome cucumber and melon SNP arrays. 2. Develop and characterize cucumber populations segregating for fruit size. 3. Combine genomic tools, segregating populations, and phenotypic characterization to identify loci associated with fruit size. As suggested by the reviewers the work concentrated mostly in cucumber and not both in cucumber and melon. In order to develop a SNP (single nucleotide polymorphism) array for cucumber, available and newly generated sequence from two cucumber cultivars with extreme differences in shape and size, pickling GY14 and Chinese long 9930, were analyzed for variation (SNPs). A large set of high quality SNPs was discovered between the two parents of the RILs population (GY14 and 9930) and used to design a custom SNP array with 35000 SNPs using Agilent technology. The array was validated using 9930, Gy14 and F1 progeny of the two parents. Several mapping populations were developed for linkage mapping of quantitative trait loci (QTL) for fruit size These includes 145 F3 families and 150 recombinant inbred line (RILs F7 or F8 (Gy14 X 9930) and third population contained 450 F2 plants from a cross between Gy14 and a wild plant from India. The main population that was used in this study is the RILs population of Gy14 X 9930. Phenotypic and morphological analyses of 9930, Gy14, and their segregating F2 and RIL progeny indicated that several, likely independent, factors influence cucumber fruit size and shape, including factors that act both pre-anthesis and post-pollination. These include: amount, rate, duration, and plane of cell division pre- and post-anthesis and orientation of cell expansion. Analysis of F2 and RIL progeny indicated that factors influencing fruit length were largely determined pre-anthesis, while fruit diameter was more strongly influenced by environment and growth factors post-anthesis. These results suggest involvement of multiple genetically segregating factors expected to map independently onto the cucumber genome. Using the SNP array and the phenotypic data two major QTLs for fruit size of cucumber were mapped in very high accuracy (around 300 Kb) with large set of markers that should facilitate identification and cloning of major genes that contribute to fruit size in cucumber. In addition, a highly accurate haplotype map of all RILS was created to allow fine mapping of other traits segregating in this population. A detailed cucumber genetic map with 6000 markers was also established (currently the most detailed genetic map of cucumber). The integration of genetics physiology and genomic approaches in this project yielded new major infrastructure tools that can be used for understanding fruit size and many other traits of importance in cucumber. The SNP array and genetic population with an ultra-fine map can be used for future breeding efforts, high resolution mapping and cloning of traits of interest that segregate in this population. The genetic map that was developed can be used for other breeding efforts in other populations. The study of fruit development that was done during this project will be important in dissecting function of genes that that contribute to the fruit size QTLs. The SNP array can be used as tool for mapping different traits in cucumber. The development of the tools and knowledge will thus promote genetic improvement of cucumber and related cucurbits.