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Sample records for rat model electronic

  1. Does prolonged pneumoperitoneum affect the kidney? Oxidative stress, stereological and electron microscopy study in a rat model

    Directory of Open Access Journals (Sweden)

    Diogo B. de Souza

    2013-01-01

    Full Text Available Purpose: Pneumoperitoneum (Pp at 12 to 15 mmHg in rats is associated with kidney damage. However, Pp at 8 mmHg is now known to best correlate to working pressures used in humans. Thus the aim of this work was to study the kidney of rats submitted to prolonged Pp at 8 mmHg. Materials and Methods: Rats were divided into a Sham group (n = 14, submitted to anesthesia, and a Pp group (n = 14, submitted to Pp at 8 mmHg, followed by deflation. In both groups, 7 animals were immediately killed and their kidneys were used for oxidative stress analyses. The remaining 7 rats in each group were evaluated after 6 weeks for the number of glomeruli and podocyte morphology. Results: For all analyzed parameters Sham and Pp groups presented no statistical difference. Conclusion: When submitted to adequate Pp pressures (8 mmHg, no kidney damage occurs in rats.

  2. Geometrical model for the electron

    International Nuclear Information System (INIS)

    El-Sherbini, T.M.

    1985-07-01

    A model for an electron of finite dimensions is proposed. This model disregards the concept of electronic charge and leads to Bohr's frequency formula for the hydrogen atom and to Maxwell's equations for electromagnetic fields. The stability of a free electron under the action of centrifugal and transverse forces is discussed. (author)

  3. Electron-microscopic autoradiography of tritiated testosterone in rat testis

    International Nuclear Information System (INIS)

    Frederik, P.M.; Molen, H.J. van der; Galjaard, H.; Klepper, D.

    1977-01-01

    The feasibility of a technique for autoradiography of diffusible substances has been further tested by analysing the localization of steroids in rats testes with the light- and electron-microscope. Testes of rats were perfused with tritiated testosterone (3 min) followed by 15-min perfusion with buffer containing a 100-fold excess of unlabelled testosterone. Tissue samples were frozen, freeze dried, fixed in osmium vapour and embedded in Epon. To exclude extraction of steroids, contact with water and other solvents was prevented during cutting of thin sections on an ultracryotome and further treatment for autoradiography. Light- and electron-microscopic observations indicated that the highest concentration of labelled testosterone was present within the basal parts of the Sertoli cell cytoplasm and in lipid inclusions of Sertoli cells within the seminiferous tubules. This is the first account of autoradiography of steroids at the electron-microscope level. (author)

  4. Modeling Incoherent Electron Cloud Effects

    International Nuclear Information System (INIS)

    Vay, Jean-Luc; Benedetto, E.; Fischer, W.; Franchetti, G.; Ohmi, K.; Schulte, D.; Sonnad, K.; Tomas, R.; Vay, J.-L.; Zimmermann, F.; Rumolo, G.; Pivi, M.; Raubenheimer, T.

    2007-01-01

    Incoherent electron effects could seriously limit the beam lifetime in proton or ion storage rings, such as LHC, SPS, or RHIC, or blow up the vertical emittance of positron beams, e.g., at the B factories or in linear-collider damping rings. Different approaches to modeling these effects each have their own merits and drawbacks. We describe several simulation codes which simplify the descriptions of the beam-electron interaction and of the accelerator structure in various different ways, and present results for a toy model of the SPS. In addition, we present evidence that for positron beams the interplay of incoherent electron-cloud effects and synchrotron radiation can lead to a significant increase in vertical equilibrium emittance. The magnitude of a few incoherent e+e- scattering processes is also estimated. Options for future code development are reviewed

  5. Localization of lead in rat peripheral nerve by electron microscopy

    International Nuclear Information System (INIS)

    Windebank, A.J.; Dyck, P.J.

    1985-01-01

    Lead intoxication in rats reliably produces segmental demyelination. Following a single intravenous injection of radioactive lead, localization of tracer was observed sequentially by quantitative electron microscopical autoradiography. The animals injected had been on a lead-containing diet for 70 days; as a result, the blood-nerve barrier was broken down and demyelination was proceeding. Six hours after a single dose, the lead was localized to the endoneurial space of the peroneal nerve, and 72 hours later, to the myelin membrane. Lead may exert a direct effect on the membrane and alter its stability both by altering the lipid content of the membrane and by directly interfering with the lamellar structure

  6. Impact of electronic-cigarette refill liquid on rat testis.

    Science.gov (United States)

    El Golli, N; Rahali, D; Jrad-Lamine, A; Dallagi, Y; Jallouli, M; Bdiri, Y; Ba, N; Lebret, M; Rosa, J P; El May, M; El Fazaa, S

    2016-07-01

    Electronic cigarettes (e-cigarettes) are becoming the fashionable alternative to decrease tobacco smoking, although their impact on health has not been fully assessed yet. The present study was designed to compare the impact of e-cigarette refill liquid (e-liquid) without nicotine to e-liquid with nicotine on rat testis. For this purpose, e-liquid with nicotine and e-liquid without nicotine (0.5 mg/kg of body weight) were administered to adult male Wistar rats via the intraperitoneally route during four weeks. Results showed that e-liquid with or without nicotine leads to diminished sperm density and viability, such as a decrease in testicular lactate dehydrogenase activity and testosterone level. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) analysis identified a reduction in cytochrome P450 side-chain cleavage (P450 scc) and 17 beta-hydroxysteroid dehydrogenase (17βHSD) mRNA level, two key enzymes of steroidogenesis. Following e-liquid exposure, histopathological examination showed alterations in testis tissue marked by germ cells desquamation, disorganization of the tubular contents of testis and cell deposits in seminiferous tubules. Finally, analysis of oxidative stress status pointed an outbreak of antioxidant enzyme activities such as superoxide dismutase, catalase and gluthatione-S-transferase, as well as an important increase in sulfhydril group content. Taken together, these results indicate that e-liquid per se induces toxicity in Wistar rat testis, similar to e-liquid with nicotine, by disrupting oxidative balance and steroidogenesis.

  7. Oxidative stress of crystalline lens in rat menopausal model

    OpenAIRE

    Acer, Semra; Pekel, Gökhan; Küçükatay, Vural; Karabulut, Aysun; Yağcı, Ramazan; Çetin, Ebru Nevin; Akyer, Şahika Pınar; Şahin, Barbaros

    2016-01-01

    ABSTRACT Purpose: To evaluate lenticular oxidative stress in rat menopausal models. Methods: Forty Wistar female albino rats were included in this study. A total of thirty rats underwent oophorectomy to generate a menopausal model. Ten rats that did not undergo oophorectomy formed the control group (Group 1). From the rats that underwent oophorectomy, 10 formed the menopause control group (Group 2), 10 were administered a daily injection of methylprednisolone until the end of the study (Gro...

  8. Electron-plasmon model in the electron liquid theory

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    M.V.Vavrukh

    2005-01-01

    Full Text Available Here we propose an accurate approach to the description of the electron liquid model in the electron and plasmon terms. Our ideas in the present paper are close to the conception of the collective variables which was developed in the papers of Bohm and Pines. However we use another body of mathematics in the transition to the expanded space of variable particles and plasmons realized by the transition operator. It is evident that in the Random Phase Approximation (RPA, the model which consists of two interactive subsystems of electrons and plasmons is equivalent to the electron liquid model with Coulomb interaction.

  9. Vlasov fluid model with electron pressure

    International Nuclear Information System (INIS)

    Gerwin, R.

    1975-11-01

    The Vlasov-ion, fluid-electron model of Freidberg for studying the linear stability of hot-ion pinch configurations is here extended to include electron pressure. Within the framework of an adiabatic electron-gas picture, it is shown that this model is still amenable to the numerical methods described by Lewis and Freidberg

  10. Analytical local electron-electron interaction model potentials for atoms

    International Nuclear Information System (INIS)

    Neugebauer, Johannes; Reiher, Markus; Hinze, Juergen

    2002-01-01

    Analytical local potentials for modeling the electron-electron interaction in an atom reduce significantly the computational effort in electronic structure calculations. The development of such potentials has a long history, but some promising ideas have not yet been taken into account for further improvements. We determine a local electron-electron interaction potential akin to those suggested by Green et al. [Phys. Rev. 184, 1 (1969)], which are widely used in atom-ion scattering calculations, electron-capture processes, and electronic structure calculations. Generalized Yukawa-type model potentials are introduced. This leads, however, to shell-dependent local potentials, because the origin behavior of such potentials is different for different shells as has been explicated analytically [J. Neugebauer, M. Reiher, and J. Hinze, Phys. Rev. A 65, 032518 (2002)]. It is found that the parameters that characterize these local potentials can be interpolated and extrapolated reliably for different nuclear charges and different numbers of electrons. The analytical behavior of the corresponding localized Hartree-Fock potentials at the origin and at long distances is utilized in order to reduce the number of fit parameters. It turns out that the shell-dependent form of Green's potential, which we also derive, yields results of comparable accuracy using only one shell-dependent parameter

  11. An improved experimental model for peripheral neuropathy in rats

    Directory of Open Access Journals (Sweden)

    Q.M. Dias

    2013-03-01

    Full Text Available A modification of the Bennett and Xie chronic constriction injury model of peripheral painful neuropathy was developed in rats. Under tribromoethanol anesthesia, a single ligature with 100% cotton glace thread was placed around the right sciatic nerve proximal to its trifurcation. The change in the hind paw reflex threshold after mechanical stimulation observed with this modified model was compared to the change in threshold observed in rats subjected to the Bennett and Xie or the Kim and Chung spinal ligation models. The mechanical threshold was measured with an automated electronic von Frey apparatus 0, 2, 7, and 14 days after surgery, and this threshold was compared to that measured in sham rats. All injury models produced significant hyperalgesia in the operated hind limb. The modified model produced mean ± SD thresholds in g (19.98 ± 3.08, 14.98 ± 1.86, and 13.80 ± 1.00 at 2, 7, and 14 days after surgery, respectively similar to those obtained with the spinal ligation model (20.03 ± 1.99, 13.46 ± 2.55, and 12.46 ± 2.38 at 2, 7, and 14 days after surgery, respectively, but less variable when compared to the Bennett and Xie model (21.20 ± 8.06, 18.61 ± 7.69, and 18.76 ± 6.46 at 2, 7, and 14 days after surgery, respectively. The modified method required less surgical skill than the spinal nerve ligation model.

  12. An improved experimental model for peripheral neuropathy in rats

    International Nuclear Information System (INIS)

    Dias, Q.M.; Rossaneis, A.C.; Fais, R.S.; Prado, W.A.

    2013-01-01

    A modification of the Bennett and Xie chronic constriction injury model of peripheral painful neuropathy was developed in rats. Under tribromoethanol anesthesia, a single ligature with 100% cotton glace thread was placed around the right sciatic nerve proximal to its trifurcation. The change in the hind paw reflex threshold after mechanical stimulation observed with this modified model was compared to the change in threshold observed in rats subjected to the Bennett and Xie or the Kim and Chung spinal ligation models. The mechanical threshold was measured with an automated electronic von Frey apparatus 0, 2, 7, and 14 days after surgery, and this threshold was compared to that measured in sham rats. All injury models produced significant hyperalgesia in the operated hind limb. The modified model produced mean ± SD thresholds in g (19.98 ± 3.08, 14.98 ± 1.86, and 13.80 ± 1.00 at 2, 7, and 14 days after surgery, respectively) similar to those obtained with the spinal ligation model (20.03 ± 1.99, 13.46 ± 2.55, and 12.46 ± 2.38 at 2, 7, and 14 days after surgery, respectively), but less variable when compared to the Bennett and Xie model (21.20 ± 8.06, 18.61 ± 7.69, and 18.76 ± 6.46 at 2, 7, and 14 days after surgery, respectively). The modified method required less surgical skill than the spinal nerve ligation model

  13. An improved experimental model for peripheral neuropathy in rats

    Directory of Open Access Journals (Sweden)

    Q.M. Dias

    Full Text Available A modification of the Bennett and Xie chronic constriction injury model of peripheral painful neuropathy was developed in rats. Under tribromoethanol anesthesia, a single ligature with 100% cotton glace thread was placed around the right sciatic nerve proximal to its trifurcation. The change in the hind paw reflex threshold after mechanical stimulation observed with this modified model was compared to the change in threshold observed in rats subjected to the Bennett and Xie or the Kim and Chung spinal ligation models. The mechanical threshold was measured with an automated electronic von Frey apparatus 0, 2, 7, and 14 days after surgery, and this threshold was compared to that measured in sham rats. All injury models produced significant hyperalgesia in the operated hind limb. The modified model produced mean ± SD thresholds in g (19.98 ± 3.08, 14.98 ± 1.86, and 13.80 ± 1.00 at 2, 7, and 14 days after surgery, respectively similar to those obtained with the spinal ligation model (20.03 ± 1.99, 13.46 ± 2.55, and 12.46 ± 2.38 at 2, 7, and 14 days after surgery, respectively, but less variable when compared to the Bennett and Xie model (21.20 ± 8.06, 18.61 ± 7.69, and 18.76 ± 6.46 at 2, 7, and 14 days after surgery, respectively. The modified method required less surgical skill than the spinal nerve ligation model.

  14. An improved experimental model for peripheral neuropathy in rats

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Q.M.; Rossaneis, A.C.; Fais, R.S.; Prado, W.A. [Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

    2013-03-15

    A modification of the Bennett and Xie chronic constriction injury model of peripheral painful neuropathy was developed in rats. Under tribromoethanol anesthesia, a single ligature with 100% cotton glace thread was placed around the right sciatic nerve proximal to its trifurcation. The change in the hind paw reflex threshold after mechanical stimulation observed with this modified model was compared to the change in threshold observed in rats subjected to the Bennett and Xie or the Kim and Chung spinal ligation models. The mechanical threshold was measured with an automated electronic von Frey apparatus 0, 2, 7, and 14 days after surgery, and this threshold was compared to that measured in sham rats. All injury models produced significant hyperalgesia in the operated hind limb. The modified model produced mean ± SD thresholds in g (19.98 ± 3.08, 14.98 ± 1.86, and 13.80 ± 1.00 at 2, 7, and 14 days after surgery, respectively) similar to those obtained with the spinal ligation model (20.03 ± 1.99, 13.46 ± 2.55, and 12.46 ± 2.38 at 2, 7, and 14 days after surgery, respectively), but less variable when compared to the Bennett and Xie model (21.20 ± 8.06, 18.61 ± 7.69, and 18.76 ± 6.46 at 2, 7, and 14 days after surgery, respectively). The modified method required less surgical skill than the spinal nerve ligation model.

  15. A classical model for the electron

    International Nuclear Information System (INIS)

    Visser, M.

    1989-01-01

    The construction of classical and semi-classical models for the electron has had a long and distinguished history. Such models are useful more for what they teach us about field theory than what they teach us about the electron. In this Letter I exhibit a classical model of the electron consisting of ordinary electromagnetism coupled with a self-interacting version of Newtonian gravity. The gravitational binding energy of the system balances the electrostatic energy in such a manner that the total rest mass of the electron is finite. (orig.)

  16. Ideal Experimental Rat Models for Liver Diseases.

    Science.gov (United States)

    Lee, Sang Woo; Kim, Sung Hoon; Min, Seon Ok; Kim, Kyung Sik

    2011-05-01

    There are many limitations for conducting liver disease research in human beings due to the high cost and potential ethical issues. For this reason, conducting a study that is difficult to perform in humans using appropriate animal models, can be beneficial in ascertaining the pathological physiology, and in developing new treatment modalities. However, it is difficult to determine the appropriate animal model which is suitable for research purposes, since every patient has different and diverse clinical symptoms, adverse reactions, and complications due to the pathological physiology. Also, it is not easy to reproduce identically various clinical situations in animal models. Recently, the Guide for the Care and Use of Laboratory Animals has tightened up the regulations, and therefore it is advisable to select the appropriate animals and decide upon the appropriate quantities through scientific and systemic considerations before conducting animal testing. Therefore, in this review article the authors examined various white rat animal testing models and determined the appropriate usable rat model, and the pros and cons of its application in liver disease research. The authors believe that this review will be beneficial in selecting proper laboratory animals for research purposes.

  17. Nutritional support contributes to recuperation in a rat model of aplastic anemia by enhancing mitochondrial function.

    Science.gov (United States)

    Yang, Guang; Zhao, Lifen; Liu, Bing; Shan, Yujia; Li, Yang; Zhou, Huimin; Jia, Li

    2018-02-01

    Acquired aplastic anemia (AA) is a hematopoietic stem cell disease that leads to hematopoietic disorder and peripheral blood pancytopenia. We investigated whether nutritional support is helpful to AA recovery. We established a rat model with AA. A nutrient mixture was administered to rats with AA through different dose gavage once per day for 55 d. Animals in this study were assigned to one of five groups: normal control (NC; group includes normal rats); AA (rats with AA); high dose (AA + nutritional mixture, 2266.95 mg/kg/d); medium dose (1511.3 mg/kg/d); and low dose (1057.91 mg/kg/d). The effects of nutrition administration on general status and mitochondrial function of rats with AA were evaluated. The nutrient mixture with which the rats were supplemented significantly improved weight, peripheral blood parameters, and histologic parameters of rats with AA in a dose-dependent manner. Furthermore, we observed that the number of mitochondria in the liver, spleen, kidney, and brain was increased after supplementation by transmission electron microscopy analysis. Nutrient administration also improved mitochondrial DNA content, adenosine triphosphate content, and membrane potential but inhibited oxidative stress, thus, repairing the mitochondrial dysfunction of the rats with AA. Taken together, nutrition supplements may contribute to the improvement of mitochondrial function and play an important role in the recuperation of rats with AA. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Effective electron-electron and electron-phonon interactions in the Hubbard-Holstein model

    International Nuclear Information System (INIS)

    Aprea, G.; Di Castro, C.; Grilli, M. . E-mail marco.grilli@roma1.infn.it; Lorenzana, J.

    2006-01-01

    We investigate the interplay between the electron-electron and the electron-phonon interaction in the Hubbard-Holstein model. We implement the flow-equation method to investigate within this model the effect of correlation on the electron-phonon effective coupling and, conversely, the effect of phonons in the effective electron-electron interaction. Using this technique we obtain analytical momentum-dependent expressions for the effective couplings and we study their behavior for different physical regimes. In agreement with other works on this subject, we find that the electron-electron attraction mediated by phonons in the presence of Hubbard repulsion is peaked at low transferred momenta. The role of the characteristic energies involved is also analyzed

  19. [Establishment of rat model of psychical erectile dysfunction].

    Science.gov (United States)

    Wang, Qiu-lin; Wang, Shu-ren; Duan, Jin

    2006-01-01

    To set up a method of establishing the animal model of psychical erectile dysfunction with emotional stress. All thirty-six male rats with normal sexual function were divided into three groups, i. e. normal group, model group and demasculinized group randomly according to their weights. The rats in the model group were suspended upside down in midair over the water and irritated repeatedly. Two weeks later, the sexual abilities of all rats, i. e. the times of mounting and intromitting the estrus female rats, the latent period of mounting, intromission and ejaculation, were recorded, and the number of rats that had sexual activities was also counted. And the hemorheology indices of the rats were measured. Compared with the normal rats, the latency of mounting [(152.5 +/- 24.6) s vs (42.4 +/- 9.6) s] and intromission [(437.0 +/- 67.7) s vs (130.8 +/- 39.1) s] of the model rats were longer (P 0.05). The hemorheology indices, e. g. blood viscosity, hematocrit (Hct) and red cell aggregation (RCA), of the model rats was significant higher than that of the normal and demasculinized rats (P erectile dysfunction can be made ideally with psychical stress.

  20. Establishment of animal model of dual liver transplantation in rat.

    Directory of Open Access Journals (Sweden)

    Ying Zhang

    Full Text Available The animal model of the whole-size and reduced-size liver transplantation in both rat and mouse has been successfully established. Because of the difficulties and complexities in microsurgical technology, the animal model of dual liver transplantation was still not established for twelve years since the first human dual liver transplantation has been made a success. There is an essential need to establish this animal model to lay a basic foundation for clinical practice. To study the physiological and histopathological changes of dual liver transplantation, "Y" type vein from the cross part between vena cava and two iliac of donor and "Y' type prosthesis were employed to recanalize portal vein and the bile duct between dual liver grafts and recipient. The dual right upper lobes about 45-50% of the recipient liver volume were taken as donor, one was orthotopically implanted at its original position, the other was rotated 180° sagitally and heterotopically positioned in the left upper quadrant. Microcirculation parameters, liver function, immunohistochemistry and survival were analyzed to evaluate the function of dual liver grafts. No significant difference in the hepatic microcirculatory flow was found between two grafts in the first 90 minutes after reperfusion. Light and electronic microscope showed the liver architecture was maintained without obvious features of cellular destruction and the continuity of the endothelium was preserved. Only 3 heterotopically positioned graft appeared patchy desquamation of endothelial cell, mitochondrial swelling and hepatocytes cytoplasmic vacuolization. Immunohistochemistry revealed there is no difference in hepatocyte activity and the ability of endothelia to contract and relax after reperfusion between dual grafts. Dual grafts made a rapid amelioration of liver function after reperfusion. 7 rats survived more than 7 days with survival rate of 58.3.%. Using "Y" type vein and bile duct prosthesis, we

  1. Transient Hypothyroidism During Lactation Arrests Myelination in the Anterior Commissure of Rats. A Magnetic Resonance Image and Electron Microscope Study.

    Science.gov (United States)

    Lucia, Federico S; Pacheco-Torres, Jesús; González-Granero, Susana; Canals, Santiago; Obregón, María-Jesús; García-Verdugo, José M; Berbel, Pere

    2018-01-01

    Thyroid hormone deficiency at early postnatal ages affects the cytoarchitecture and function of neocortical and telencephalic limbic areas, leading to impaired associative memory and in a wide spectrum of neurological and mental diseases. Neocortical areas project interhemispheric axons mostly through the corpus callosum and to a lesser extent through the anterior commissure (AC), while limbic areas mostly project through the AC and hippocampal commissures. Functional magnetic resonance data from children with late diagnosed congenital hypothyroidism and abnormal verbal memory processing, suggest altered ipsilateral and contralateral telencephalic connections. Gestational hypothyroidism affects AC development but the possible effect of transient and chronic postnatal hypothyroidism, as occurs in late diagnosed neonates with congenital hypothyroidism and in children growing up in iodine deficient areas, still remains unknown. We studied AC development using in vivo magnetic resonance imaging and electron microscopy in hypothyroid and control male rats. Four groups of methimazole (MMI) treated rats were studied. One group was MMI-treated from postnatal day (P) 0 to P21; some of these rats were also treated with L-thyroxine (T4) from P15 to P21, as a model for early transient hypothyroidism. Other rats were MMI-treated from P0 to P150 and from embryonic day (E) 10 to P170, as a chronic hypothyroidism group. The results were compared with age paired control rats. The normalized T2 signal using magnetic resonance image was higher in MMI-treated rats and correlated with the number and percentage of myelinated axons. Using electron microscopy, we observed decreased myelinated axon number and density in transient and chronic hypothyroid rats at P150, unmyelinated axon number increased slightly in chronic hypothyroid rats. In MMI-treated rats, the myelinated axon g-ratio and conduction velocity was similar to control rats, but with a decrease in conduction delays. These

  2. Transient Hypothyroidism During Lactation Arrests Myelination in the Anterior Commissure of Rats. A Magnetic Resonance Image and Electron Microscope Study

    Directory of Open Access Journals (Sweden)

    Federico S. Lucia

    2018-04-01

    Full Text Available Thyroid hormone deficiency at early postnatal ages affects the cytoarchitecture and function of neocortical and telencephalic limbic areas, leading to impaired associative memory and in a wide spectrum of neurological and mental diseases. Neocortical areas project interhemispheric axons mostly through the corpus callosum and to a lesser extent through the anterior commissure (AC, while limbic areas mostly project through the AC and hippocampal commissures. Functional magnetic resonance data from children with late diagnosed congenital hypothyroidism and abnormal verbal memory processing, suggest altered ipsilateral and contralateral telencephalic connections. Gestational hypothyroidism affects AC development but the possible effect of transient and chronic postnatal hypothyroidism, as occurs in late diagnosed neonates with congenital hypothyroidism and in children growing up in iodine deficient areas, still remains unknown. We studied AC development using in vivo magnetic resonance imaging and electron microscopy in hypothyroid and control male rats. Four groups of methimazole (MMI treated rats were studied. One group was MMI-treated from postnatal day (P 0 to P21; some of these rats were also treated with L-thyroxine (T4 from P15 to P21, as a model for early transient hypothyroidism. Other rats were MMI-treated from P0 to P150 and from embryonic day (E 10 to P170, as a chronic hypothyroidism group. The results were compared with age paired control rats. The normalized T2 signal using magnetic resonance image was higher in MMI-treated rats and correlated with the number and percentage of myelinated axons. Using electron microscopy, we observed decreased myelinated axon number and density in transient and chronic hypothyroid rats at P150, unmyelinated axon number increased slightly in chronic hypothyroid rats. In MMI-treated rats, the myelinated axon g-ratio and conduction velocity was similar to control rats, but with a decrease in conduction

  3. Evaluation by electronic paramagnetic resonance of the number of free radicals produced in irradiated rat bone

    International Nuclear Information System (INIS)

    Marble, G.; Valderas, R.

    1966-01-01

    The number of long half-life free radicals created by gamma irradiation in the bones of the rat has been determined from the electrons paramagnetic resonance spectrum. This number decreases slowly with time (calculated half life: 24 days). It is proportional to the dose of gamma radiation given to the rat. The method could find interesting applications in the field of biological dosimetry. (authors) [fr

  4. Status of Galileo interim radiation electron model

    Science.gov (United States)

    Garrett, H. B.; Jun, I.; Ratliff, J. M.; Evans, R. W.; Clough, G. A.; McEntire, R. W.

    2003-01-01

    Measurements of the high energy, omni-directional electron environment by the Galileo spacecraft Energetic Particle Detector (EDP) were used to develop a new model of Jupiter's trapped electron radiation in the jovian equatorial plane for the range 8 to 16 Jupiter radii.

  5. An Electronic Publishing Model for Academic Publishers.

    Science.gov (United States)

    Gold, Jon D.

    1994-01-01

    Describes an electronic publishing model based on Standard Generalized Markup Language (SGML) and considers its use by an academic publisher. Highlights include how SGML is used to produce an electronic book, hypertext, methods of delivery, intellectual property rights, and future possibilities. Sample documents are included. (two references) (LRW)

  6. Modeling microwave/electron-cloud interaction

    International Nuclear Information System (INIS)

    Mattes, M; Sorolla, E; Zimmermann, F

    2013-01-01

    Starting from the separate codes BI-RME and ECLOUD or PyECLOUD, we are developing a novel joint simulation tool, which models the combined effect of a charged particle beam and of microwaves on an electron cloud. Possible applications include the degradation of microwave transmission in telecommunication satellites by electron clouds; the microwave-transmission techniques being used in particle accelerators for the purpose of electroncloud diagnostics; the microwave emission by the electron cloud itself in the presence of a magnetic field; and the possible suppression of electron-cloud formation in an accelerator by injecting microwaves of suitable amplitude and frequency. A few early simulation results are presented. (author)

  7. Electron scattering in the interacting boson model

    NARCIS (Netherlands)

    Dieperink, AEL; Iachello, F; Rinat, A; Creswell, C

    1978-01-01

    It is suggested that the interacting boson model be used in the analysis of electron scattering data. Qualitative features of the expected behavior of the inelastic excitation of some 2 ÷ states inthe transitional Sm-Nd region are discussed

  8. ENU mutagenesis to generate genetically modified rat models.

    Science.gov (United States)

    van Boxtel, Ruben; Gould, Michael N; Cuppen, Edwin; Smits, Bart M G

    2010-01-01

    The rat is one of the most preferred model organisms in biomedical research and has been extremely useful for linking physiology and pathology to the genome. However, approaches to genetically modify specific genes in the rat germ line remain relatively scarce. To date, the most efficient approach for generating genetically modified rats has been the target-selected N-ethyl-N-nitrosourea (ENU) mutagenesis-based technology. Here, we describe the detailed protocols for ENU mutagenesis and mutant retrieval in the rat model organism.

  9. Thrombolytic and anticoagulation treatment in a rat embolic stroke model

    DEFF Research Database (Denmark)

    Rasmussen, Rune Skovgaard; Overgaard, K; Meden, P

    2003-01-01

    OBJECTIVES: The effects of pentasaccharide (PENTA), given alone or combined with thrombolysis using recombinant tissue plasminogen activator (rt-PA), on infarct size and clinical outcome were evaluated in a rat embolic stroke model. MATERIALS AND METHODS: Ninety-two rats were embolized unilateral...... alone or combined with rt-PA did not significantly increase mortality or tendency for hemorrhage.......OBJECTIVES: The effects of pentasaccharide (PENTA), given alone or combined with thrombolysis using recombinant tissue plasminogen activator (rt-PA), on infarct size and clinical outcome were evaluated in a rat embolic stroke model. MATERIALS AND METHODS: Ninety-two rats were embolized unilaterally...

  10. Kinetic electron model for plasma thruster plumes

    Science.gov (United States)

    Merino, Mario; Mauriño, Javier; Ahedo, Eduardo

    2018-03-01

    A paraxial model of an unmagnetized, collisionless plasma plume expanding into vacuum is presented. Electrons are treated kinetically, relying on the adiabatic invariance of their radial action integral for the integration of Vlasov's equation, whereas ions are treated as a cold species. The quasi-2D plasma density, self-consistent electric potential, and electron pressure, temperature, and heat fluxes are analyzed. In particular, the model yields the collisionless cooling of electrons, which differs from the Boltzmann relation and the simple polytropic laws usually employed in fluid and hybrid PIC/fluid plume codes.

  11. Striatal grafts in a rat model of Huntington's disease

    DEFF Research Database (Denmark)

    Guzman, R; Meyer, M; Lövblad, K O

    1999-01-01

    Survival and integration into the host brain of grafted tissue are crucial factors in neurotransplantation approaches. The present study explored the feasibility of using a clinical MR scanner to study striatal graft development in a rat model of Huntington's disease. Rat fetal lateral ganglionic...... time-points graft location could not be further verified. Measures for graft size and ventricle size obtained from MR images highly correlated with measures obtained from histologically processed sections (R = 0.8, P fetal rat lateral ganglionic...

  12. Electronic Payments Profitability Extent Model

    Directory of Open Access Journals (Sweden)

    Rudolf Vohnout

    2016-12-01

    Full Text Available Cashless payments are recent phenomena, which even increased with the introduction of contactless means like NFC, PayPass or payWave. Such new methods speed-up the entire payment process and in comparison to cash transactions are much simpler and faster. But on the other hand the key question for merchant is if it is worth to have such device, which accept these new payment means or not to have the terminal at all. What is the amount of cash flow, which delimits the cash holdings to be still profitable? This paper tries to give answers to such question by presenting general profitability model, which will address defining the cash threshold amount. The aim is to show that cash holdings could be profitable up to certain amount, but after the threshold is met, cashless payment methods are fairly superior despite their additional costs.

  13. Electron conductivity model for dense plasmas

    International Nuclear Information System (INIS)

    Lee, Y.T.; More, R.M.

    1984-01-01

    An electron conductivity model for dense plasmas is described which gives a consistent and complete set of transport coefficients including not only electrical conductivity and thermal conductivity, but also thermoelectric power, and Hall, Nernst, Ettinghausen, and Leduc--Righi coefficients. The model is useful for simulating plasma experiments with strong magnetic fields. The coefficients apply over a wide range of plasma temperature and density and are expressed in a computationally simple form. Different formulas are used for the electron relaxation time in plasma, liquid, and solid phases. Comparisons with recent calculations and available experimental measurement show the model gives results which are sufficiently accurate for many practical applications

  14. Model Comparison for Electron Thermal Transport

    Science.gov (United States)

    Moses, Gregory; Chenhall, Jeffrey; Cao, Duc; Delettrez, Jacques

    2015-11-01

    Four electron thermal transport models are compared for their ability to accurately and efficiently model non-local behavior in ICF simulations. Goncharov's transport model has accurately predicted shock timing in implosion simulations but is computationally slow and limited to 1D. The iSNB (implicit Schurtz Nicolai Busquet electron thermal transport method of Cao et al. uses multigroup diffusion to speed up the calculation. Chenhall has expanded upon the iSNB diffusion model to a higher order simplified P3 approximation and a Monte Carlo transport model, to bridge the gap between the iSNB and Goncharov models while maintaining computational efficiency. Comparisons of the above models for several test problems will be presented. This work was supported by Sandia National Laboratory - Albuquerque and the University of Rochester Laboratory for Laser Energetics.

  15. A Rat Excised Larynx Model of Vocal Fold Scar

    Science.gov (United States)

    Welham, Nathan V.; Montequin, Douglas W.; Tateya, Ichiro; Tateya, Tomoko; Choi, Seong Hee; Bless, Diane M.

    2009-01-01

    Purpose: To develop and evaluate a rat excised larynx model for the measurement of acoustic, aerodynamic, and vocal fold vibratory changes resulting from vocal fold scar. Method: Twenty-four 4-month-old male Sprague-Dawley rats were assigned to 1 of 4 experimental groups: chronic vocal fold scar, chronic vocal fold scar treated with 100-ng basic…

  16. ENU mutagenesis to generate genetically modified rat models

    NARCIS (Netherlands)

    van Boxtel, R.; Gould, M.; Cuppen, E.; Smits, B.M.

    2010-01-01

    The rat is one of the most preferred model organisms in biomedical research and has been extremely useful for linking physiology and pathology to the genome. However, approaches to genetically modify specific genes in the rat germ line remain relatively scarce. To date, the most efficient approach

  17. Electron autoradiographic study of intracellular conversion of fatty acids into glycogen in rats with alloxan diabetes

    International Nuclear Information System (INIS)

    Lebkova, N.P.; Bobkov, Y.I.; Gorbonova, V.D.; Kolesova, O.E.

    1985-01-01

    An electron-autoradiographic study was undertaken of the intracellular distribution of hydrogen of fatty acids in alloxan diabetes. Alloxan diabetes was induced in rats; between 2 weeks and 2 months after development of the disease 0.1 ml of tritium-oleic or tritium-arachidonic acid was injected into the caudel vein of the rats. After decapitation, myocardial tissue from the subendocardial zone of the left ventricle, liver tissue, and glycogen isolated from the liver by a biochemical method, were taken for electron-autoradiographic investigation. Analysis of the data showed that a radioactive isotope, injected into the blood stream of the animals in the form of oleic or arachidonic acids, is incorporated into various structures of hepatocytes and cardiomyocytes. Direct proof is obtained to show that glycogen in hepatocytes and cardiomyoctyes of diabetic rats may be formed from fatty acids

  18. Teaching Chemistry with Electron Density Models

    Science.gov (United States)

    Shusterman, Gwendolyn P.; Shusterman, Alan J.

    1997-07-01

    Linus Pauling once said that a topic must satisfy two criteria before it can be taught to students. First, students must be able to assimilate the topic within a reasonable amount of time. Second, the topic must be relevant to the educational needs and interests of the students. Unfortunately, the standard general chemistry textbook presentation of "electronic structure theory", set as it is in the language of molecular orbitals, has a difficult time satisfying either criterion. Many of the quantum mechanical aspects of molecular orbitals are too difficult for most beginning students to appreciate, much less master, and the few applications that are presented in the typical textbook are too limited in scope to excite much student interest. This article describes a powerful new method for teaching students about electronic structure and its relevance to chemical phenomena. This method, which we have developed and used for several years in general chemistry (G.P.S.) and organic chemistry (A.J.S.) courses, relies on computer-generated three-dimensional models of electron density distributions, and largely satisfies Pauling's two criteria. Students find electron density models easy to understand and use, and because these models are easily applied to a broad range of topics, they successfully convey to students the importance of electronic structure. In addition, when students finally learn about orbital concepts they are better prepared because they already have a well-developed three-dimensional picture of electronic structure to fall back on. We note in this regard that the types of models we use have found widespread, rigorous application in chemical research (1, 2), so students who understand and use electron density models do not need to "unlearn" anything before progressing to more advanced theories.

  19. Fine structure of the endolymphatic duct in the rat. A scanning and transmission electron microscopy study

    DEFF Research Database (Denmark)

    Qvortrup, K; Rostgaard, Jørgen; Bretlau, P

    1995-01-01

    To investigate the surface morphology of the endolymphatic duct epithelium, 8 rats were vascularly perfused with glutaraldehyde in a buffered and oxygenated blood substitute. Optimal preservation of the epithelium for scanning electron microscopy was attained by coating of the specimens with OsO4...

  20. Scanning electron microscopy of rat throat and trachea following the effects of radon decay products

    International Nuclear Information System (INIS)

    Rode, J.; Vaupotic, J.; Kobal, I.; Draslar, K.

    1996-01-01

    In two preliminary experiments, five laboratory rats were exposed in a small chamber to radon-rich air. In both experiments the exposure was about 0.9 WLM. The surface of throat and trachea was examined by scanning electron microscope. (author)

  1. Exact diagonalization library for quantum electron models

    Science.gov (United States)

    Iskakov, Sergei; Danilov, Michael

    2018-04-01

    We present an exact diagonalization C++ template library (EDLib) for solving quantum electron models, including the single-band finite Hubbard cluster and the multi-orbital impurity Anderson model. The observables that can be computed using EDLib are single particle Green's functions and spin-spin correlation functions. This code provides three different types of Hamiltonian matrix storage that can be chosen based on the model.

  2. The Anderson model for electron localisation

    International Nuclear Information System (INIS)

    Pruisken, A.M.M.; Schaefer, L.

    1982-01-01

    The Anderson model for localisation problems is treated with field theory employing the replica trick. We show that no valid perturbation theory results out of the usual (S2)2 formalism due to mishandling of symmetries. The problem is reformulated in terms of matrix fields. It is shown that the Anderson model asymptotically exhibits an exact local gauge symmetry. Elimination of massive longitudinal components leads to a non-compact sigma model, obtained earlier for the description of electronic disorder. We thus establish that the Anderson model is in the same universality class as Wegner's gauge invariant real matrix model. (orig.)

  3. The action of a dietary retinoid on gene expression and cancer induction in electron-irradiated rat skin

    International Nuclear Information System (INIS)

    Burns, F.J.; Chen, S.; Xu, G.; Wu, F.; Tang, M.S.

    2002-01-01

    Current models of radiation carcinogenesis generally assume that the DNA is damaged in a variety of ways by the radiation and that subsequent cell divisions contribute to the conversion of the damage to heritable mutations. Cancer may seem complex and intractable, but its complexity provides multiple opportunities for preventive interventions. Mitotic inhibitors are among the strongest cancer preventive agents, not only slowing the growth rate of preneoplasias but also increasing the fidelity of DNA repair processes. Ionizing radiation, including electrons, is a strong inducer of cancer in rat skin, and dietary retinoids have shown potent cancer preventive activity in the same system. A non-toxic dietary dose of retinyl acetate altered gene expression levels 24 hours after electron irradiation of rat skin. Of the 8740 genes on an Affymetrix rat expression array, the radiation significantly (5 fold or higher) altered 188, while the retinoid altered 231, including 16 radiation-altered genes that were reversely altered. While radiation strongly affected the expression of stress response, immune/inflammation and nucleic acid metabolism genes, the retinoid most strongly affected proliferation-related genes, including some significant reversals, such as, keratin 14, retinol binding protein, and calcium binding proteins. These results point to reversal of proliferation-relevant genes as a likely basis for the anti-radiogenic effects of dietary retinyl acetate. (author)

  4. Analgesic synergism of gabapentin and carbamazepine in rat model ...

    African Journals Online (AJOL)

    Analgesic synergism of gabapentin and carbamazepine in rat model of diabetic neuropathic pain. Sinan Mohammed Abdullah AL-Mahmood, Shahrin Tarmizi Bin Che Abdullah, Nik Nur Fatnoon Nik Ahmad, Abdul Hadi Bin Mohamed, Tariq Abdul Razak ...

  5. Electron scattering in the interacting boson model

    International Nuclear Information System (INIS)

    Dieperink, A.E.L.; Iachello, F.; Creswell, C.

    1978-01-01

    It is suggested that the interacting boson model be used in the analysis of electron scattering data. Qualitative features of the expected behavior of the inelastic excitation of some 2 + states in the transitional Sm-Nd region are discussed. (Auth.)

  6. Electron Correlation Models for Optical Activity

    DEFF Research Database (Denmark)

    Höhn, E. G.; O. E. Weigang, Jr.

    1968-01-01

    A two-system no-overlap model for rotatory strength is developed for electric-dipole forbidden as well as allowed transitions. General equations which allow for full utilization of symmetry in the chromophore and in the environment are obtained. The electron correlation terms are developed in full...

  7. Dietary models for inducing hypercholesterolemia in rats

    Directory of Open Access Journals (Sweden)

    Sheyla Leite Matos

    2005-03-01

    Full Text Available The present work aimed at finding a dietetical model capable of promoting the highest hypercholesterolemia without affecting the development of the rats. Sixty female Fisher rats were divided into five groups. The first one was fed a control diet; the remaining four were fed hypercholesterolemic diets with cholesterol and different contents of soybean oil, starch, casein, micronutrients and fiber and, consequently, different caloric values. After eight weeks animals were evaluated in relation to growth, fecal excretion, liver weight and fat, cholesterol and its fractions, serum biochemical parameters and sistolic pressure and compared with controls. The best result was obtained with the diet containing 25 % soybean oil, 1.0 % cholesterol, 13 % fiber and 4,538.4 Kcal/Kg, since it promoted an increase in LDL-cholesterol, a decrease in the HDL fraction and affected less the hepatic function of the animals.Modelos animais têm sido usados para investigar a relação entre desordens no metabolismo do colesterol e a aterogênese. A estratégia utilizada a fim de induzir hipercolesterolemia (dietas com alto teor de gordura e com colesterol adicionado leva à redução de sua ingestão pelos animais, o que induz desnutrição. O presente trabalho objetivou encontrar um modelo dietético capaz de promover a maior hipercolesterolemia, sem afetar o desenvolvimento dos animais. Sessenta ratas Fisher foram divididas em cinco grupos. O primeiro foi alimentado com uma dieta controle; os quatros restantes receberam dietas hipercolesterolêmicas, com colesterol e diferentes teores de óleo de soja, amido, caseína, micronutrientes e fibra e, conseqüentemente, diferentes valores calóricos. Após oito semanas os animais foram avaliados em relação ao crescimento, excreção fecal, peso e teor de gordura do fígado, colesterol e suas frações, parâmetros bioquímicos séricos e pressão sistólica. Os melhores resultados foram obtidos com a dieta contendo 25

  8. Model Order Reduction for Electronic Circuits:

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Shontz, Suzanne

    Electronic circuits are ubiquitous; they are used in numerous industries including: the semiconductor, communication, robotics, auto, and music industries (among many others). As products become more and more complicated, their electronic circuits also grow in size and complexity. This increased...... in the semiconductor industry. Circuit simulation proceeds by using Maxwell’s equations to create a mathematical model of the circuit. The boundary element method is then used to discretize the equations, and the variational form of the equations are then solved on the graph network....

  9. A model for disruption generated runaway electrons

    International Nuclear Information System (INIS)

    Russo, A.J.; Campbell, R.B.

    1993-01-01

    One of the possible consequences of disruptions in tokamaks is the generation of runaway electrons which can impact plasma facing components and cause damage, owing to high local energy deposition. This problem becomes more serious as the machine size and plasma current increase. Since large size and high currents are characteristics of proposed future machines, control of runaway generation is an important design consideration. A lumped circuit model for disruption runaway electron generation indicates that impurity concentration and type, as well as plasma motion, can strongly influence runaway behaviour. A comparison of disruption data from several runs on JET and DIII-D with model results demonstrate the effects of impurities, and plasma motion, on runaway number density and energy. The model is also applied to the calculation of runaway currents for ITER. (author). 16 refs, 13 figs

  10. Phenotypic Characterization of LEA Rat: A New Rat Model of Nonobese Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Tadashi Okamura

    2013-01-01

    Full Text Available Animal models have provided important information for the genetics and pathophysiology of diabetes. Here we have established a novel, nonobese rat strain with spontaneous diabetes, Long-Evans Agouti (LEA rat derived from Long-Evans (LE strain. The incidence of diabetes in the males was 10% at 6 months of age and 86% at 14 months, while none of the females developed diabetes. The blood glucose level in LEA male rats was between 200 and 300 mg/dl at 120 min according to OGTT. The glucose intolerance in correspondence with the impairment of insulin secretion was observed in male rats, which was the main cause of diabetes in LEA rats. Histological examination revealed that the reduction of β-cell mass was caused by progressive fibrosis in pancreatic islets in age-dependent manner. The intracytoplasmic hyaline droplet accumulation and the disappearance of tubular epithelial cell layer associated with thickening of basement membrane were evident in renal proximal tubules. The body mass index and glycaemic response to exogenous insulin were comparable to those of control rats. The unique characteristics of LEA rat are a great advantage not only to analyze the progression of diabetes, but also to disclose the genes involved in type 2 diabetes mellitus.

  11. An experimental study on choroidal neovascularization induced by Krypton laser in rat model.

    Science.gov (United States)

    Cui, Jing; Liu, Yuanyuan; Zhang, Jingkai; Yan, Hua

    2014-01-01

    The purpose of this work was to study the efficacy and safety of choroidal neovascularization (CNV) formation induced by Krypton laser in Brown Norway (BN) rats, and observe the trend of the change of CNV after laser photocoagulation. Twenty-five male BN rats were involved in this study. Two eyes of one rat without any laser photocoagulation were randomly selected as the control group, and the other 48 eyes of 24 rats were selected as the experimental group. Eight eyes of four rats were randomly selected to receive the examinations of fundus fluorescein angiography (FFA), histopathology, and transmission electron microscopy 3, 7, 14, 21, 28, and 56 days after laser photocoagulation. After laser photocoagulation, the leakage appeared in burns on day 7 (59%), reached the peak on day 21 (84%), (p0.05). The thickness of CNV increased from day 7 to day 21 (p0.05). The experimental model of CNV can be successfully induced by Krypton laser in rats with a stable, long-lasting, and high success rate. After laser photocoagulation, the leakages appear on day 7, reach the peak on day 21, and remain stable after day 21.

  12. Modeling the Nab Experiment Electronics in SPICE

    Science.gov (United States)

    Blose, Alexander; Crawford, Christopher; Sprow, Aaron; Nab Collaboration

    2017-09-01

    The goal of the Nab experiment is to measure the neutron decay coefficients a, the electron-neutrino correlation, as well as b, the Fierz interference term to precisely test the Standard Model, as well as probe for Beyond the Standard Model physics. In this experiment, protons from the beta decay of the neutron are guided through a magnetic field into a Silicon detector. Event reconstruction will be achieved via time-of-flight measurement for the proton and direct measurement of the coincident electron energy in highly segmented silicon detectors, so the amplification circuitry needs to preserve fast timing, provide good amplitude resolution, and be packaged in a high-density format. We have designed a SPICE simulation to model the full electronics chain for the Nab experiment in order to understand the contributions of each stage and optimize them for performance. Additionally, analytic solutions to each of the components have been determined where available. We will present a comparison of the output from the SPICE model, analytic solution, and empirically determined data.

  13. Stochastic model of the spinning electron

    International Nuclear Information System (INIS)

    Simaciu, I.; Borsos, Z.

    2002-01-01

    In Stochastic Electrodynamics (SED) it is demonstrated that electrostatic interaction is the result of the scattering of the Classical Zero-Point Field (CZPF) background by the charged particles. In such models, the electron is modelled as a two-dimensional oscillator, which interacts with the electric component of the CZPF background. The electron with spin is not only an electric monopole but also a magnetic dipole. The interaction of the spin electron with the CZPF background is not only electric but also magnetic. We calculate the scattering cross-section of magnetic dipole in the situation when a magnetic field, variable in time B arrow = B 0 arrow sin ωt, acts over the rigid magnetic dipole given by the symmetry of the model. The cross-section of a magnetic dipole σ m must be equal to the cross-section of an electric monopole σ e . This equality between σ m and σ e cross-sections is motivated, too, by the fact that, in the model of the two-dimensional oscillator, the electric charge q e has the motion speed c. (authors)

  14. Classical Electron Model with QED Corrections

    OpenAIRE

    Lenk, Ron

    2010-01-01

    In this article we build a metric for a classical general relativistic electron model with QED corrections. We calculate the stress-energy tensor for the radiative corrections to the Coulomb potential in both the near-field and far-field approximations. We solve the three field equations in both cases by using a perturbative expansion to first order in alpha (the fine-structure constant) while insisting that the usual (+, +, -, -) structure of the stress-energy tensor is maintained. The resul...

  15. Models of fast-electron penetration

    International Nuclear Information System (INIS)

    Perry, D.J.; Raisis, S.K.

    1994-01-01

    We introduce multiple scattering models of charged-particle penetration which are based on the previous analyses of Yang and Perry. Our development removes the main limitations of the Fermi-Eyges approach while retaining its considerable potential as a theory which is useful for applied work. We illustrate key predictions with sample calculations that are of particular interest in therapeutic applications, 5-20 MeV electrons incident on water. 8 refs., 5 figs

  16. Model potential for electron scattering from rubidium

    Energy Technology Data Exchange (ETDEWEB)

    Gien, T.E. (Memorial Univ. of Newfoundland, St. John' s, NF (Canada). Dept. of Physics)

    1992-11-28

    An analytic model potential for the e[sup -]-Rb[sup +] system is generated from experimental data, using an iteration method. The potential obtained can reproduce rather accurately the energy levels of rubidium. We employed it in the calculation of elastic differential cross sections for electron (and positron) scatterings from rubidium in the conventional Glauber approximation. The differential cross sections calculated in the model potential approach are compared to those in the frozen-core approach, employing either the Clementi-Roetti or the Szasz-McGinn wavefunctions. The core correlation and polarization effects are found to significantly affect the cross section results. (author).

  17. Model potential for electron scattering from rubidium

    International Nuclear Information System (INIS)

    Gien, T.E.

    1992-01-01

    An analytic model potential for the e - -Rb + system is generated from experimental data, using an iteration method. The potential obtained can reproduce rather accurately the energy levels of rubidium. We employed it in the calculation of elastic differential cross sections for electron (and positron) scatterings from rubidium in the conventional Glauber approximation. The differential cross sections calculated in the model potential approach are compared to those in the frozen-core approach, employing either the Clementi-Roetti or the Szasz-McGinn wavefunctions. The core correlation and polarization effects are found to significantly affect the cross section results. (author)

  18. Cannabis exacerbates depressive symptoms in rat model induced by reserpine.

    Science.gov (United States)

    Khadrawy, Yasser A; Sawie, Hussein G; Abdel-Salam, Omar M E; Hosny, Eman N

    2017-05-01

    Cannabis sativa is one of the most widely recreational drugs and its use is more prevalent among depressed patients. Some studies reported that Cannabis has antidepressant effects while others showed increased depressive symptoms in Cannabis users. Therefore, the present study aims to investigate the effect of Cannabis extract on the depressive-like rats. Twenty four rats were divided into: control, rat model of depression induced by reserpine and depressive-like rats treated with Cannabis sativa extract (10mg/kg expressed as Δ9-tetrahydrocannabinol). The depressive-like rats showed a severe decrease in motor activity as assessed by open field test (OFT). This was accompanied by a decrease in monoamine levels and a significant increase in acetylcholinesterase activity in the cortex and hippocampus. Na + ,K + -ATPase activity increased in the cortex and decreased in the hippocampus of rat model. In addition, a state of oxidative stress was evident in the two brain regions. This was indicated from the significant increase in the levels of lipid peroxidation and nitric oxide. No signs of improvement were observed in the behavioral and neurochemical analyses in the depressive-like rats treated with Cannabis extract. Furthermore, Cannabis extract exacerbated the lipid peroxidation in the cortex and hippocampus. According to the present findings, it could be concluded that Cannabis sativa aggravates the motor deficits and neurochemical changes induced in the cortex and hippocampus of rat model of depression. Therefore, the obtained results could explain the reported increase in the depressive symptoms and memory impairment among Cannabis users. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. A novel model of invasive fungal rhinosinusitis in rats.

    Science.gov (United States)

    Zhang, Fang; An, Yunfang; Li, Zeqing; Zhao, Changqing

    2013-01-01

    Invasive fungal rhinosinusitis (IFRS) is a life-threatening inflammatory disease that affects immunocompromised patients, but animal models of the disease are scarce. This study aimed to develop an IFRS model in neutropenic rats. The model was established in three consecutive steps: unilateral nasal obstruction with Merocel sponges, followed by administration of cyclophosphamide (CPA), and, finally, nasal inoculation with Aspergillus fumigatus. Fifty healthy Wistar rats were randomly divided into five groups, with group I as the controls, group II undergoing unilateral nasal obstruction alone, group III undergoing nasal obstruction with fungal inoculation, group IV undergoing nasal obstruction with administration of CPA, and group V undergoing nasal obstruction with administration of CPA and fungal inoculation. Hematology, histology, and mycology investigations were performed. The changes in the rat absolute neutrophil counts (ANCs) were statistically different across the groups. The administration of CPA decreased the ANCs, whereas nasal obstruction with fungal inoculation increased the ANCs, and nasal obstruction did not change them. Histological examination of the rats in group V revealed the hyphal invasion of sinus mucosa and bone, thrombosis, and tissue infarction. No pathology indicative of IFRS was observed in the remaining groups. Positive rates of fungal culture in tissue homogenates from the maxillary sinus (62.5%) and lung (25%) were found in group V, whereas groups I, II, III, and IV showed no fungal culture in the homogenates. A rat IFRS model was successfully developed through nasal obstruction, CPA-induced neutropenia, and fungal inoculation. The disease model closely mimics the pathophysiology of anthropic IFRS.

  20. Cerebral microbleeds in a neonatal rat model.

    Directory of Open Access Journals (Sweden)

    Brianna Carusillo Theriault

    Full Text Available In adult humans, cerebral microbleeds play important roles in neurodegenerative diseases but in neonates, the consequences of cerebral microbleeds are unknown. In rats, a single pro-angiogenic stimulus in utero predisposes to cerebral microbleeds after birth at term, a time when late oligodendrocyte progenitors (pre-oligodendrocytes dominate in the rat brain. We hypothesized that two independent pro-angiogenic stimuli in utero would be associated with a high likelihood of perinatal microbleeds that would be severely damaging to white matter.Pregnant Wistar rats were subjected to intrauterine ischemia (IUI and low-dose maternal lipopolysaccharide (mLPS at embryonic day (E 19. Pups were born vaginally or abdominally at E21-22. Brains were evaluated for angiogenic markers, microhemorrhages, myelination and axonal development. Neurological function was assessed out to 6 weeks.mRNA (Vegf, Cd31, Mmp2, Mmp9, Timp1, Timp2 and protein (CD31, MMP2, MMP9 for angiogenic markers, in situ proteolytic activity, and collagen IV immunoreactivity were altered, consistent with an angiogenic response. Vaginally delivered pups exposed to prenatal IUI+mLPS had spontaneous cerebral microbleeds, abnormal neurological function, and dysmorphic, hypomyelinated white matter and axonopathy. Pups exposed to the same pro-angiogenic stimuli in utero but delivered abdominally had minimal cerebral microbleeds, preserved myelination and axonal development, and neurological function similar to naïve controls.In rats, pro-angiogenic stimuli in utero can predispose to vascular fragility and lead to cerebral microbleeds. The study of microbleeds in the neonatal rat brain at full gestation may give insights into the consequences of microbleeds in human preterm infants during critical periods of white matter development.

  1. Oxidative stress of crystalline lens in rat menopausal model.

    Science.gov (United States)

    Acer, Semra; Pekel, Gökhan; Küçükatay, Vural; Karabulut, Aysun; Yağcı, Ramazan; Çetin, Ebru Nevin; Akyer, Şahika Pınar; Şahin, Barbaros

    2016-01-01

    To evaluate lenticular oxidative stress in rat menopausal models. Forty Wistar female albino rats were included in this study. A total of thirty rats underwent oophorectomy to generate a menopausal model. Ten rats that did not undergo oophorectomy formed the control group (Group 1). From the rats that underwent oophorectomy, 10 formed the menopause control group (Group 2), 10 were administered a daily injection of methylprednisolone until the end of the study (Group 3), and the remaining 10 rats were administered intraperitoneal streptozocin to induce diabetes mellitus (Group 4). Total oxidant status (TOS), total antioxidant capacity (TAC), and oxidative stress index (OSI) measurements of the crystalline lenses were analyzed. The mean OSI was the lowest in group 1 and highest in group 4. Nevertheless, the difference between the groups was not statistically significant in terms of OSI (p >0.05). The mean TOS values were similar between the groups (p >0.05), whereas the mean TAC of group 1 was significantly higher than that of the other groups (p <0.001). Our results indicate that menopause may not promote cataract formation.

  2. Oxidative stress of crystalline lens in rat menopausal model

    Directory of Open Access Journals (Sweden)

    Semra Acer

    Full Text Available ABSTRACT Purpose: To evaluate lenticular oxidative stress in rat menopausal models. Methods: Forty Wistar female albino rats were included in this study. A total of thirty rats underwent oophorectomy to generate a menopausal model. Ten rats that did not undergo oophorectomy formed the control group (Group 1. From the rats that underwent oophorectomy, 10 formed the menopause control group (Group 2, 10 were administered a daily injection of methylprednisolone until the end of the study (Group 3, and the remaining 10 rats were administered intraperitoneal streptozocin to induce diabetes mellitus (Group 4. Total oxidant status (TOS, total antioxidant capacity (TAC, and oxidative stress index (OSI measurements of the crystalline lenses were analyzed. Results: The mean OSI was the lowest in group 1 and highest in group 4. Nevertheless, the difference between the groups was not statistically significant in terms of OSI (p >0.05. The mean TOS values were similar between the groups (p >0.05, whereas the mean TAC of group 1 was significantly higher than that of the other groups (p <0.001. Conclusions: Our results indicate that menopause may not promote cataract formation.

  3. Long-term BPA infusions. Evaluation in the rat brain tumor and rat spinal cord models

    International Nuclear Information System (INIS)

    Coderre, J.A.; Micca, P.L.; Nawrocky, M.M.; Joel, D.D.; Morris, G.M.

    2000-01-01

    In the BPA-based dose escalation clinical trial, the observations of tumor recurrence in areas of extremely high calculated tumor doses suggest that the BPA distribution is non-uniform. Longer (6-hour) i.v. infusions of BPA are evaluated in the rat brain tumor and spinal cord models to address the questions of whether long-term infusions are more effective against the tumor and whether long-term infusions are detrimental in the central nervous system. In the rat spinal cord, the 50% effective doses (ED 50 ) for myeloparesis were not significantly different after a single i.p. injection of BPA-fructose or a 6 hour i.v. infusion. In the rat 9L gliosarcoma brain tumor model, BNCT following 2-hr or 6-hr infusions of BPA-F produced similar levels of long term survival. (author)

  4. Analysis of operating model of electronic invoice colombian Colombian electronic billing analysis of the operational model

    Directory of Open Access Journals (Sweden)

    Sérgio Roberto da Silva

    2016-06-01

    Full Text Available Colombia has been one of the first countries to introduce electronic billing process on a voluntary basis, from a traditional to a digital version. In this context, the article analyzes the electronic billing process implemented in Colombia and the advantages. Methodological research is applied, qualitative, descriptive and documentary; where the regulatory framework and the conceptualization of the model is identified; the process of adoption of electronic billing is analyzed, and finally the advantages and disadvantages of its implementation is analyzed. The findings indicate that the model applied in Colombia to issue an electronic billing in sending and receiving process, is not complex, but it requires a small adequate infrastructure and trained personnel to reach all sectors, especially the micro and business which is the largest business network in the country.

  5. Gut Microbial Diversity in Rat Model Induced by Rhubarb

    Science.gov (United States)

    Peng, Ying; Wu, Chunfu; Yang, Jingyu; Li, Xiaobo

    2014-01-01

    Rhubarb is often used to establish chronic diarrhea and spleen (Pi)-deficiency syndrome animal models in China. In this study, we utilized the enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) method to detect changes in bacterial diversity in feces and the bowel mucosa associated with this model. Total microbial genomic DNA from the small bowel (duodenum, jejunum, and ileum), large bowel (proximal colon, distal colon, and rectum), cecum, and feces of normal and rhubarb-exposed rats were used as templates for the ERIC-PCR analysis. We found that the fecal microbial composition did not correspond to the bowel bacteria mix. More bacterial diversity was observed in the ileum of rhubarb-exposed rats (Panalysis with the SPSS software, the Canonical Discriminant Function Formulae for model rats was established. PMID:25048267

  6. Characterizing a Rat Brca2 Knockout Model

    Science.gov (United States)

    2007-05-01

    Brca2 was tested in various tumor inducing experimental settings [49,52] * activated form Hs = Homo sapiens ; Rn = Rattus norvegicus; MMTV...sequencing gDNA from a wild-type 2 SD rat over a region of intron 21 that contains the splicing branch site 2 (underlined). ( el The same sequence from the...from the El pups at 1 week of age for macromolecule isolation. We also visually checked all Fk pups for gross abnormalities in physi- cal

  7. Modelling transport in single electron transistor

    International Nuclear Information System (INIS)

    Dinh Sy Hien; Huynh Lam Thu Thao; Le Hoang Minh

    2009-01-01

    We introduce a model of single electron transistor (SET). Simulation programme of SET is used as the exploratory tool in order to gain better understanding of process and device physics. This simulator includes a graphic user interface (GUI) in Matlab. The SET was simulated using GUI in Matlab to get current-voltage (I-V) characteristics. In addition, effects of device capacitance, bias, temperature on the I-V characteristics were obtained. In this work, we review the capabilities of the simulator of the SET. Typical simulations of the obtained I-V characteristics of the SET are presented.

  8. Beneficial effect of daidzin in dry eye rat model through the suppression of inflammation and oxidative stress in the cornea

    Directory of Open Access Journals (Sweden)

    Fan Xiao

    2018-05-01

    Full Text Available Present investigation evaluates the effect of daidzin in dry eye rat model through the suppression of inflammation and oxidative stress in the cornea. Briefly, electron spine resonance was used for the estimation of radical scavenging activity of daidzin and COX Fluorescent Activity Assay Kit was used for the estimation of PGS activity. Dry eye rat model was developed by removing the lacrimal gland and effect of daidzin was evaluated in dry eye rat model by estimating the fluorescein score, tear volume and expressions of heme oxigenase (HO-1, TNF α, Interlukin 6 (IL-6, matrix metallopeptidase 9 (MMP-9 and PGS-2. Result of the present study suggested that daidzin possess tyrosyl radical scavenging activity and thereby decreases the oxidative stress. Activity of PGS significantly increases in dry eye which was inhibited by daidzin treatment due to competitive inhibition of PGS. It also recovers the tear volume in dry eye rat model in which lacrimal gland was removed. Thus corneal erosion was improved by daidzin in dry eye rat model. Thus present study concludes that treatment with daidzin protects the cornea in dry eye rat model by suppression inflammation and oxidative stress. Keywords: Daidzin, Dry eye, Radical scavenging activity, Inflammation

  9. Beneficial effect of daidzin in dry eye rat model through the suppression of inflammation and oxidative stress in the cornea.

    Science.gov (United States)

    Xiao, Fan; Cui, Hua; Zhong, Xiao

    2018-05-01

    Present investigation evaluates the effect of daidzin in dry eye rat model through the suppression of inflammation and oxidative stress in the cornea. Briefly, electron spine resonance was used for the estimation of radical scavenging activity of daidzin and COX Fluorescent Activity Assay Kit was used for the estimation of PGS activity. Dry eye rat model was developed by removing the lacrimal gland and effect of daidzin was evaluated in dry eye rat model by estimating the fluorescein score, tear volume and expressions of heme oxigenase (HO-1), TNF α, Interlukin 6 (IL-6), matrix metallopeptidase 9 (MMP-9) and PGS-2. Result of the present study suggested that daidzin possess tyrosyl radical scavenging activity and thereby decreases the oxidative stress. Activity of PGS significantly increases in dry eye which was inhibited by daidzin treatment due to competitive inhibition of PGS. It also recovers the tear volume in dry eye rat model in which lacrimal gland was removed. Thus corneal erosion was improved by daidzin in dry eye rat model. Thus present study concludes that treatment with daidzin protects the cornea in dry eye rat model by suppression inflammation and oxidative stress.

  10. Transmission electron microscopy of heart and liver tissues from rats fed with gums arabic and tragacanth.

    Science.gov (United States)

    Anderson, D M; Ashby, P; Busuttil, A; Kempson, S A; Lawson, M E

    1984-04-01

    Transmission electron microscopy has been used to examine the ultrastructure of rat hearts and livers after diet supplementation with (a) 0, 0.5, 1.5, 2.5 and 3.5% (w/w) gum tragacanth (GT) for 91 days, (b) 0 and 1% GT for 5 days (c) 0, 1, 4 and 8% (w/w) gum arabic (GA) for 28 days. The preparation and scrutiny of the electron micrographs was undertaken by two independent teams of specialists. There were no detectable abnormalities in any of the organelles in the heart and liver specimens from any of the test animals and no inclusions nor other pathological changes were observed. All micrographs showed normal, healthy tissues; particular attention was given to the mitochondria in hepatocytes as they serve as sensitive indicators of the health and state of activity of cells. In addition, the data obtained from assays of the microsomal protein and cytochrome P-450 content of the livers showed that GA and GT did not cause inductive effects. These results do not support earlier suggestions, based on in vitro assays, that GA and GT cause changes in the function of rat heart and liver mitochondria and liver microsomes; however, they confirm a report by Zbinden that the ingestion of GT does not produce abnormalities in the cardiac function of rats.

  11. Persistent estrus rat models of polycystic ovary disease: an update.

    Science.gov (United States)

    Singh, Krishna B

    2005-10-01

    To critically review published articles on polycystic ovary (PCO) disease in rat models, with a focus on delineating its pathophysiology. Review of the English-language literature published from 1966 to March 2005 was performed through PubMed search. Keywords or phrases used were persistent estrus, chronic anovulation, polycystic ovary, polycystic ovary disease, and polycystic ovary syndrome. Articles were also located via bibliographies of published literature. University Health Sciences Center. Articles on persistent estrus and PCO in rats were selected and reviewed regarding the methods for induction of PCO disease. Changes in the reproductive cycle, ovarian morphology, hormonal parameters, and factors associated with the development of PCO disease in rat models were analyzed. Principal methods for inducing PCO in the rat include exposure to constant light, anterior hypothalamic and amygdaloidal lesions, and the use of androgens, estrogens, antiprogestin, and mifepristone. The validated rat PCO models provide useful information on morphologic and hormonal disturbances in the pathogenesis of chronic anovulation in this condition. These studies have aimed to replicate the morphologic and hormonal characteristics observed in the human PCO syndrome. The implications of these studies to human condition are discussed.

  12. Infrared Thermography in Serotonin-Induced Itch Model in Rats

    DEFF Research Database (Denmark)

    Jasemian, Yousef; Gazerani, Parisa; Dagnæs-Hansen, Frederik

    2012-01-01

    The study validated the application of infrared thermography in a serotonin-induced itch model in rats since the only available method in animal models of itch is the count of scratching bouts. Twenty four adult Sprague-Dawley male rats were used in 3 experiments: 1) local vasomotor response...... with no scratching reflex was investigated. Serotonin elicited significant scratching and lowered the local temperature at the site of injection. A negative dose-temperature relationship of serotonin was found by thermography. Vasoregulation at the site of serotonin injection took place in the absence of scratching...

  13. Morphofunctional analysis of experimental model of esophageal achalasia in rats.

    Science.gov (United States)

    Sabirov, A G; Raginov, I S; Burmistrov, M V; Chelyshev, Y A; Khasanov, R Sh; Moroshek, A A; Grigoriev, P N; Zefirov, A L; Mukhamedyarov, M A

    2010-10-01

    We carried out a detailed analysis of rat model of esophageal achalasia previously developed by us. Manifest morphological and functional disorders were observed in experimental achalasia: hyperplasia of the squamous epithelium, reduced number of nerve fibers, excessive growth of fibrous connective tissue in the esophageal wall, high contractile activity of the lower esophageal sphincter, and reduced motility of the longitudinal muscle layer. Changes in rat esophagus observed in experimental achalasia largely correlate with those in esophageal achalasia in humans. Hence, our experimental model can be used for the development of new methods of disease treatment.

  14. Surface morphology of the endolymphatic duct in the rat. A scanning electron microscopy study

    DEFF Research Database (Denmark)

    Qvortrup, K; Rostgaard, Jørgen; Bretlau, P

    1995-01-01

    microscopy was attained by coating of the specimens with osmium tetroxide and thiocarbohydrazide followed by a continuous dehydration procedure. This technique permitted, for the first time, an investigation of the surface morphology of the epithelial cells in the endolymphatic duct. Three types of cells......Following intracardiac vascular perfusion fixation of 8 rats with glutaraldehyde in a buffered and oxygenated blood substitute, the vestibular aqueduct and endolymphatic duct were opened by microsurgery of the resulting 16 temporal bones. Optimum preservation of the epithelium for scanning electron...... were identified with the scanning electron microscope. A polygonal and oblong epithelial cell was observed in the largest number throughout the duct, and in the juxtasaccular half of the duct, two additional types of epithelial cells were observed. The scanning electron microscopic observations...

  15. Model based design of electronic throttle control

    Science.gov (United States)

    Cherian, Fenin; Ranjan, Ashish; Bhowmick, Pathikrit; Rammohan, A.

    2017-11-01

    With the advent of torque based Engine Management Systems, the precise control and robust performance of the throttle body becomes a key factor in the overall performance of the vehicle. Electronic Throttle Control provides benefits such as improved air-fuel ratio for improving the vehicle performance and lower exhausts emissions to meet the stringent emission norms. Modern vehicles facilitate various features such as Cruise Control, Traction Control, Electronic Stability Program and Pre-crash systems. These systems require control over engine power without driver intervention, which is not possible with conventional mechanical throttle system. Thus these systems are integrated to function with the electronic throttle control. However, due to inherent non-linearities in the throttle body, the control becomes a difficult task. In order to eliminate the influence of this hysteresis at the initial operation of the butterfly valve, a control to compensate the shortage must be added to the duty required for starting throttle operation when the initial operation is detected. Therefore, a lot of work is being done in this field to incorporate the various nonlinearities to achieve robust control. In our present work, the ETB was tested to verify the working of the system. Calibration of the TPS sensors was carried out in order to acquire accurate throttle opening angle. The response of the calibrated system was then plotted against a step input signal. A linear model of the ETB was prepared using Simulink and its response was compared with the experimental data to find out the initial deviation of the model from the actual system. To reduce this deviation, non-linearities from existing literature were introduced to the system and a response analysis was performed to check the deviation from the actual system. Based on this investigation, an introduction of a new nonlinearity parameter can be used in future to reduce the deviation further making the control of the ETB more

  16. Modeling ion sensing in molecular electronics

    International Nuclear Information System (INIS)

    Chen, Caroline J.; Smeu, Manuel; Ratner, Mark A.

    2014-01-01

    We examine the ability of molecules to sense ions by measuring the change in molecular conductance in the presence of such charged species. The detection of protons (H + ), alkali metal cations (M + ), calcium ions (Ca 2+ ), and hydronium ions (H 3 O + ) is considered. Density functional theory (DFT) is used within the Keldysh non-equilibrium Green's function framework (NEGF) to model electron transport properties of quinolinedithiol (QDT, C 9 H 7 NS 2 ), bridging Al electrodes. The geometry of the transport region is relaxed with DFT. The transport properties of the device are modeled with NEGF-DFT to determine if this device can distinguish among the M + + QDT species containing monovalent cations, where M + = H + , Li + , Na + , or K + . Because of the asymmetry of QDT in between the two electrodes, both positive and negative biases are considered. The electron transmission function and conductance properties are simulated for electrode biases in the range from −0.5 V to 0.5 V at increments of 0.1 V. Scattering state analysis is used to determine the molecular orbitals that are the main contributors to the peaks in the transmission function near the Fermi level of the electrodes, and current-voltage relationships are obtained. The results show that QDT can be used as a proton detector by measuring transport through it and can conceivably act as a pH sensor in solutions. In addition, QDT may be able to distinguish among different monovalent species. This work suggests an approach to design modern molecular electronic conductance sensors with high sensitivity and specificity using well-established quantum chemistry

  17. Simvastatin Exposure and Rotator Cuff Repair in a Rat Model.

    Science.gov (United States)

    Deren, Matthew E; Ehteshami, John R; Dines, Joshua S; Drakos, Mark C; Behrens, Steve B; Doty, Stephen; Coleman, Struan H

    2017-03-01

    Simvastatin is a common medication prescribed for hypercholesterolemia that accelerates local bone formation. It is unclear whether simvastatin can accelerate healing at the tendon-bone interface after rotator cuff repair. This study was conducted to investigate whether local and systemic administration of simvastatin increased tendon-bone healing of the rotator cuff as detected by maximum load to failure in a controlled animal-based model. Supraspinatus tendon repair was performed on 120 Sprague-Dawley rats. Sixty rats had a polylactic acid membrane overlying the repair site. Of these, 30 contained simvastatin and 30 did not contain medication. Sixty rats underwent repair without a polylactic acid membrane. Of these, 30 received oral simvastatin (25 mg/kg/d) and 30 received a regular diet. At 4 weeks, 5 rats from each group were killed for histologic analysis. At 8 weeks, 5 rats from each group were killed for histologic analysis and the remaining 20 rats were killed for biomechanical analysis. One rat that received oral simvastatin died of muscle necrosis. Average maximum load to failure was 35.2±6.2 N for those receiving oral simvastatin, 36.8±9.0 N for oral control subjects, 39.5±12.8 N for those receiving local simvastatin, and 39.1±9.3 N for control subjects with a polylactic acid membrane. No statistically significant differences were found between any of the 4 groups (P>.05). Qualitative histologic findings showed that all groups showed increased collagen formation and organization at 8 weeks compared with 4 weeks, with no differences between the 4 groups at each time point. The use of systemic and local simvastatin offered no benefit over control groups. [Orthopedics. 2017; 40(2):e288-e292.]. Copyright 2016, SLACK Incorporated.

  18. Multidisciplinary Modelling Tools for Power Electronic Circuits

    DEFF Research Database (Denmark)

    Bahman, Amir Sajjad

    in reliability assessment of power modules, a three-dimensional lumped thermal network is proposed to be used for fast, accurate and detailed temperature estimation of power module in dynamic operation and different boundary conditions. Since an important issue in the reliability of power electronics...... environment to be used for optimization of cooling system layout with respect to thermal resistance and pressure drop reductions. Finally extraction of electrical parasitics in the multi-chip power modules will be investigated. As the switching frequency of power devices increases, the size of passive...... components are reduced considerably that leads to increase of power density and cost reduction. However, electrical parasitics become more challenging with increasing the switching frequency and paralleled chips in the integrated and denser packages. Therefore, electrical parasitic models are analyzed based...

  19. Generation and characterization of rat liver stem cell lines and their engraftment in a rat model of liver failure

    Science.gov (United States)

    Kuijk, Ewart W.; Rasmussen, Shauna; Blokzijl, Francis; Huch, Meritxell; Gehart, Helmuth; Toonen, Pim; Begthel, Harry; Clevers, Hans; Geurts, Aron M.; Cuppen, Edwin

    2016-01-01

    The rat is an important model for liver regeneration. However, there is no in vitro culture system that can capture the massive proliferation that can be observed after partial hepatectomy in rats. We here describe the generation of rat liver stem cell lines. Rat liver stem cells, which grow as cystic organoids, were characterized by high expression of the stem cell marker Lgr5, by the expression of liver progenitor and duct markers, and by low expression of hepatocyte markers, oval cell markers, and stellate cell markers. Prolonged cultures of rat liver organoids depended on high levels of WNT-signalling and the inhibition of BMP-signaling. Upon transplantation of clonal lines to a Fah−/− Il2rg−/− rat model of liver failure, the rat liver stem cells engrafted into the host liver where they differentiated into areas with FAH and Albumin positive hepatocytes. Rat liver stem cell lines hold potential as consistent reliable cell sources for pharmacological, toxicological or metabolic studies. In addition, rat liver stem cell lines may contribute to the development of regenerative medicine in liver disease. To our knowledge, the here described liver stem cell lines represent the first organoid culture system in the rat. PMID:26915950

  20. A study on the effects of electron beam irradiation on tooth extraction wound healing in rats

    International Nuclear Information System (INIS)

    Suzuki, Akiyoshi

    1983-01-01

    The wound of the upper jaw 3 days after the first molar tooth extraction in female rats was exposed to 1,500 rads (Group 2) and 2,000 rads (Group 3) of the 10 MeV electron beams, and its pathohistological changes were compared with those of rats with the tooth extraction alone (control group). In the control group, the tooth extraction wound was covered with epithelium 10 days later and new bones were formed 17 days later. Wound healing with the epithelium was seen in all irradiated rats 24 days later. The formation of the new teeth was seen 24 days later in the Group 2 and 38 days later in Group 3. Cell infiltration under the epithelial layers was still observed in some of the Group 3, although the wound was covered with epithelium, and the new bone covering the extraction wound was formed 38 days later. Healing was prolonged in Group 3, as compared with that in Group 2. (Namekawa, K.)

  1. Structural and functional changes in the intenstine of irradiated and hypothermic irradiated rats : a scanning and transmission electron microscopic study

    International Nuclear Information System (INIS)

    Chaudhuri, S.; Chaudhuri, Swapna; Roy, Bijon

    1982-01-01

    Severe destructive changes in the intestine of rats following whole body exposure to gamma rays (832 rads) were observed by light microscope, scanning and transmission electron microscope studies. Hypothermia (15deg C rectal temperature) induced prior to irradiation protected the intestinal mucosa from destruction. A simultaneous study showed that glucose absorption decreased significantly in irradiated rats, whereas it was increased in hypothermic irradiated animals. (author)

  2. Steroid-associated osteonecrosis animal model in rats

    Directory of Open Access Journals (Sweden)

    Li-Zhen Zheng

    2018-04-01

    Full Text Available Summary: Objective: Established preclinical disease models are essential for not only studying aetiology and/or pathophysiology of the relevant diseases but more importantly also for testing prevention and/or treatment concept(s. The present study proposed and established a detailed induction and assessment protocol for a unique and cost-effective preclinical steroid-associated osteonecrosis (SAON in rats with pulsed injections of lipopolysaccharide (LPS and methylprednisolone (MPS. Methods: Sixteen 24-week-old male Sprague–Dawley rats were used to induce SAON by one intravenous injection of LPS (0.2 mg/kg and three intraperitoneal injections of MPS (100 mg/kg with a time interval of 24 hour, and then, MPS (40 mg/kg was intraperitoneally injected three times a week from week 2 until sacrifice. Additional 12 rats were used as normal controls. Two and six weeks after induction, animals were scanned by metabolic dual energy X-ray absorptiometry for evaluation of tissue composition; serum was collected for bone turnover markers, Microfil perfusion was performed for angiography, the liver was collected for histopathology and bilateral femora and bilateral tibiae were collected for histological examination. Results: Three rats died after LPS injection, i.e., with 15.8% (3/19 mortality. Histological evaluation showed 100% incidence of SAON at week 2. Dual energy X-ray absorptiometry showed significantly higher fat percent and lower lean mass in SAON group at week 6. Micro-computed tomography (Micro-CT showed significant bone degradation at proximal tibia 6 weeks after SAON induction. Angiography illustrated significantly less blood vessels in the proximal tibia and significantly more leakage particles in the distal tibia 2 weeks after SAON induction. Serum amino-terminal propeptide of type I collagen and osteocalcin were significantly lower at both 2 and 6 weeks after SAON induction, and serum carboxy-terminal telopeptide was significantly

  3. Physiologically Based Pharmacokinetic Model for Terbinafine in Rats and Humans

    Science.gov (United States)

    Hosseini-Yeganeh, Mahboubeh; McLachlan, Andrew J.

    2002-01-01

    The aim of this study was to develop a physiologically based pharmacokinetic (PB-PK) model capable of describing and predicting terbinafine concentrations in plasma and tissues in rats and humans. A PB-PK model consisting of 12 tissue and 2 blood compartments was developed using concentration-time data for tissues from rats (n = 33) after intravenous bolus administration of terbinafine (6 mg/kg of body weight). It was assumed that all tissues except skin and testis tissues were well-stirred compartments with perfusion rate limitations. The uptake of terbinafine into skin and testis tissues was described by a PB-PK model which incorporates a membrane permeability rate limitation. The concentration-time data for terbinafine in human plasma and tissues were predicted by use of a scaled-up PB-PK model, which took oral absorption into consideration. The predictions obtained from the global PB-PK model for the concentration-time profile of terbinafine in human plasma and tissues were in close agreement with the observed concentration data for rats. The scaled-up PB-PK model provided an excellent prediction of published terbinafine concentration-time data obtained after the administration of single and multiple oral doses in humans. The estimated volume of distribution at steady state (Vss) obtained from the PB-PK model agreed with the reported value of 11 liters/kg. The apparent volume of distribution of terbinafine in skin and adipose tissues accounted for 41 and 52%, respectively, of the Vss for humans, indicating that uptake into and redistribution from these tissues dominate the pharmacokinetic profile of terbinafine. The PB-PK model developed in this study was capable of accurately predicting the plasma and tissue terbinafine concentrations in both rats and humans and provides insight into the physiological factors that determine terbinafine disposition. PMID:12069977

  4. Effects of electrohydraulic extracorporeal shock wave lithotripsy on submandibular gland in the rat: electron microscopic evaluation.

    Science.gov (United States)

    Bayar, Nuray; Kaymaz, F Figen; Apan, Alpaslan; Yilmaz, Erdal; Cakar, A Nur

    2002-05-15

    Extracorporeal shockwave lithotripsy (ESWL) has been applied in sialolithiasis as a new treatment modality. The aim of this experimental study is to investigate the local effects of electrohydraulic ESWL applied to the right submandibular gland of the rats. This prospective study was conveyed in four groups; groups I, II, III and IV; each group consisting of 20, 20, 18 and 9 rats, respectively, with a randomized distribution. Groups I, II, III and IV received 250, 500, 1000 and 2000 shock waves at 14-16 kV (average 15.1 kV), respectively, to the right submandibular glands on the 0th day. In groups I, II, III, right submandibular glands of the rats were removed on the 0th, 1st, 7th and 15th days; in group IV, this procedure could be managed only on the 0th and 7th days. Light and electron microscopic evaluation were assessed. Using the light microscopic changes, severity of damage score of the glands (SDS) was found. Statistical analysis was done using SDSs. Light and electron microscopic observations have shown that the damage produced by the shock waves were confined to focal areas in the acinar cells (AC), granulated convoluted tubule (GCT) cells and blood vessels at all doses applied. Vacuolization in the cytoplasms of the AC and GCT cells, disintegration of membranes, alteration in the cytoplasmic organization, swelling of the mitochondria and loss of the features were observed on electron microscopy. Increase in the secretion rate; stasis and dilatation in the blood vessels; blebbing and loss of features in the cytoplasm of the endothelial cells were observed. According to the result of the statistical analysis using SDSs; at 250 shock wave dose, a statistically significant difference between the SDSs of the days (0th, 1st, 7th and 15th) was found (Pwaves (Pwaves was found to have the lower value than the SDS at the 2000 shock wave. It was observed that produced damage was less prominent by small doses (250, 500 doses) initially (0th day). Electrohydraulic

  5. Establishment of an induced rat model of malignant pleural mesothelioma

    International Nuclear Information System (INIS)

    Han Dan; Wu Beihai; Yang Hongsheng; Song Guangyi

    2004-01-01

    Objective: To establish a convenient and practical malignant pleural mesothelioma (MPM) model induced by crocidolite in Da Yao, which has a high induction rate and can be used for imaging and multiple experimental studies and is similar to human MPM. Methods 40 mg of crocidolite suspension was injected into the right chest cavity in 100 Wistar rats in the test group, while same amount of sterilized saline water was injected in 20 rats in the control group. The animals were observed daily , and weighted once a month. CT scanning was performed regularly. When the rats were dead or dying, they were dissected immediately and pathological changes were recorded after CT examination. The experiment lasted for 2 years. Results: The overall induction rate was 71.6%. The survival time of the first MPM rat was 285 days. The mean living span of rats with MPM was (469 ± 21) days. The pathological features of the induced MPMs were multiple morphologically and there were some CT features in different periods. CT imaging could show some MPM features and find the tumour earlier. Conclusion: The cause, positions, tissues and clinical condition of induced tumors were the same as humans. The model had a higher similarity with human MPM in differentiation degree and histological type, and the model can be used to study the mechanism of MPM, to discuss the measures of prevention, and to guide clinical diagnosis and treatment. Multi-morphology of the history from the induced tumors could make up the shortage, which was the difficulty in getting all periods of tissue samples in clinical research and being used in imaging and many kinds of researches. It was a valuable animal model to study MPM. (authors)

  6. Acoustic noise improves motor learning in spontaneously hypertensive rats, a rat model of attention deficit hyperactivity disorder.

    Science.gov (United States)

    Söderlund, Göran B W; Eckernäs, Daniel; Holmblad, Olof; Bergquist, Filip

    2015-03-01

    The spontaneously hypertensive (SH) rat model of ADHD displays impaired motor learning. We used this characteristic to study if the recently described acoustic noise benefit in learning in children with ADHD is also observed in the SH rat model. SH rats and a Wistar control strain were trained in skilled reach and rotarod running under either ambient noise or in 75 dBA white noise. In other animals the effect of methylphenidate (MPH) on motor learning was assessed with the same paradigms. To determine if acoustic noise influenced spontaneous motor activity, the effect of acoustic noise was also determined in the open field activity paradigm. We confirm impaired motor learning in the SH rat compared to Wistar SCA controls. Acoustic noise restored motor learning in SH rats learning the Montoya reach test and the rotarod test, but had no influence on learning in Wistar rats. Noise had no effect on open field activity in SH rats, but increased corner time in Wistar. MPH completely restored rotarod learning and performance but did not improve skilled reach in the SH rat. It is suggested that the acoustic noise benefit previously reported in children with ADHD is shared by the SH rat model of ADHD, and the effect is in the same range as that of stimulant treatment. Acoustic noise may be useful as a non-pharmacological alternative to stimulant medication in the treatment of ADHD. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  7. A Model for Teaching Electronic Commerce Students

    Directory of Open Access Journals (Sweden)

    Howard C. Woodard

    2002-10-01

    Full Text Available The teaching of information technology in an ever-changing world at universities presents a challenge. Are courses taught as concepts, while ignoring hands-on courses, leaving the hands-on classes to the technical colleges or trade schools? Does this produce the best employees for industry or give students the knowledge and skills necessary to function in a high-tech world? At GeorgiaCollege & StateUniversity (GC&SU a model was developed that combines both concepts and practical hands-on skill to meet this challenge. Using this model, a program was developed that consists of classroom lecture of concepts as well as practical hands-on exercises for mastering the knowledge and developing the skills necessary to succeed in the high-tech world of electronic commerce. The students become productive day one of a new job assignment. This solves the problem of students having the "book knowledge" but not knowing how to apply what has been learned.

  8. Oncogenic action of beta, proton, alpha and electron radiation on the rat skin

    International Nuclear Information System (INIS)

    Burns, F.J.

    1980-01-01

    Rat skin is being utilized as an empirical model for testing dose and time related aspects of the oncogenic action of ionizing radiation, ultraviolet light, and polycyclic aromatic hydrocarbons. Molecular lesions in the skin DNA, including, strand breaks and thymine dimers, are being measured and compared to tumor induction. The induction and repair kinetics of molcular lesions are being compared to split dose repair. Modifiers and radiosensitizers are being utilized to test specific aspects of a chromosome breakage theory of radiation oncogenesis

  9. Tumorigenic action of beta, proton, alpha and electron radiation on the rat skin

    International Nuclear Information System (INIS)

    Burns, F.J.

    1980-01-01

    Rat skin is utilized as a model system for studying dose and time related aspects of the oncogenic action of ionizing radiation, ultraviolet light and polycyclic aromatic hydrocarbons. Molecular lesions in the DNA of the epidermis, including strand breaks and thymine dimers, are measured and compared to the temporal and dose related aspects of tumor induction. The induction and repair kinetics of molecular lesions are compared to split dose recovery as modified by sensitizers and type of radition of oncogenic damage

  10. Electron microscopic study of the spilt irradiation effects on the rat parotid ductal cells

    International Nuclear Information System (INIS)

    Kim, Sung Soo; Lee, Sang Rae

    1988-01-01

    This study was designed to investigate the effects of split irradiation on the salivary ductal cells, especially on the intercalated cells of the rat parotid glands. For this study, 24 Sprague-Dawley strain rats were irradiated on the head and neck region with two equal split doses of 9 Gy for a 4 hours interval by Co-60 teletherapy unit, Picker's mode l 4M 60. The conditions of irradiation were that field size, dose rate, SSD and depth were 12 X 5 cm, 222 cGy/min, 50 cm and 1 cm, respectively. The experimental animals were sacrificed 1, 2, 3, 6, 12, hours and 1, 3, 7, days after the irradiation and the changes of the irradiated intercalated cells of the parotid glands were examined under light and electron microscope. The results were as follows: 1. By the split irradiation, the degenerative changes of intercalated cells of the parotid glands appeared at 3 hours after irradiation and the most severe cellular degeneration observed at 6 hours after irradiation. The repair processes began from 12 hours after irradiation and have matured progressively. 2. Under electron microscope, loss of nuclear membrane, microvilli and secretory granules, derangement of chromosomes, degeneration of cytoplasm, atrophy or reduction of intracytoplasmic organelles were observed in the intercalated ductal cells after split irradiation. 3. Under light microscope, derangement of ductal cells, widening of cytoplasms and nuclei, hyperchromatism and proliferation of ductal cells were observed in intercalated ducts after split irradiation.

  11. Shaofu Zhuyu Decoction Regresses Endometriotic Lesions in a Rat Model

    Directory of Open Access Journals (Sweden)

    Guanghui Zhu

    2018-01-01

    Full Text Available The current therapies for endometriosis are restricted by various side effects and treatment outcome has been less than satisfactory. Shaofu Zhuyu Decoction (SZD, a classic traditional Chinese medicinal (TCM prescription for dysmenorrhea, has been widely used in clinical practice by TCM doctors to relieve symptoms of endometriosis. The present study aimed to investigate the effects of SZD on a rat model of endometriosis. Forty-eight female Sprague-Dawley rats with regular estrous cycles went through autotransplantation operation to establish endometriosis model. Then 38 rats with successful ectopic implants were randomized into two groups: vehicle- and SZD-treated groups. The latter were administered SZD through oral gavage for 4 weeks. By the end of the treatment period, the volume of the endometriotic lesions was measured, the histopathological properties of the ectopic endometrium were evaluated, and levels of proliferating cell nuclear antigen (PCNA, CD34, and hypoxia inducible factor- (HIF- 1α in the ectopic endometrium were detected with immunohistochemistry. Furthermore, apoptosis was assessed using the terminal deoxynucleotidyl transferase (TdT deoxyuridine 5′-triphosphate (dUTP nick-end labeling (TUNEL assay. In this study, SZD significantly reduced the size of ectopic lesions in rats with endometriosis, inhibited cell proliferation, increased cell apoptosis, and reduced microvessel density and HIF-1α expression. It suggested that SZD could be an effective therapy for the treatment and prevention of endometriosis recurrence.

  12. Model of electron capture in low-temperature glasses

    International Nuclear Information System (INIS)

    Bartczak, W.M.; Swiatla, D.; Kroh, J.

    1983-01-01

    The new model of electron capture by a statistical variety of traps in glassy matrices is proposed. The electron capture is interpreted as the radiationless transition (assisted by multiphonon emission) of the mobile electron to the localized state in the trap. The conception of 'unfair' and 'fair' traps is introduced. The 'unfair' trap captures the mobile electron by the shallow excited state. In contrast, the 'fair' trap captures the electron by the ground state. The model calculations of the statistical distributions of the occupied electron traps are presented and discussed with respect to experimental results. (author)

  13. Characterization of a frozen shoulder model using immobilization in rats.

    Science.gov (United States)

    Kim, Du Hwan; Lee, Kil-Ho; Lho, Yun-Mee; Ha, Eunyoung; Hwang, Ilseon; Song, Kwang-Soon; Cho, Chul-Hyun

    2016-12-08

    The objective of this study was to investigate serial changes for histology of joint capsule and range of motion of the glenohumeral joint after immobilization in rats. We hypothesized that a rat shoulder contracture model using immobilization would be capable of producing effects on the glenohumeral joint similar to those seen in patients with frozen shoulder. Sixty-four Sprague-Dawley rats were randomly divided into one control group (n = 8) and seven immobilization groups (n = 8 per group) that were immobilized with molding plaster for 3 days, or for 1, 2, 3, 4, 5, or 6 weeks. At each time point, eight rats were euthanized for histologic evaluation of the axillary recess and for measurement of the abduction angle. Infiltration of inflammatory cells was found in the synovial tissue until 2 weeks after immobilization. However, inflammatory cells were diminished and fibrosis was dominantly observed in the synovium and subsynovial tissue 3 weeks after immobilization. From 1 week after immobilization, the abduction angle of all immobilization groups at each time point was significantly lower than that of the control group. Our study demonstrated that a rat frozen shoulder model using immobilization generates the pathophysiologic process of inflammation leading to fibrosis on the glenohumeral joint similar to that seen in patients with frozen shoulder. This model was attained within 3 weeks after immobilization. It may serve as a useful tool to investigate pathogenesis at the molecular level and identify potential target genes that are involved in the development of frozen shoulder.

  14. Genital mycoplasmosis in rats: a model for intrauterine infection.

    Science.gov (United States)

    Brown, M B; Peltier, M; Hillier, M; Crenshaw, B; Reyes, L

    2001-09-01

    Microbial infections of the chorioamnion and amniotic fluid have devastating effects on pregnancy outcome and neonatal morbidity and mortality. The mechanisms by which bacterial pathogens cause adverse effects are best addressed by an animal model of the disease with a naturally-occurring pathogen. Intrauterine infection in humans as well as genital mycoplasmosis in humans and rodents is reviewed. We describe a genital infection in rats, which provides a model for the role of infection in pregnancy, pregnancy wastage, low birth weight, and fetal infection. Infection of Sprague-Dawley rats with Mycoplasma pulmonis either vaginally or intravenously resulted in decreased litter size, increased adverse pregnancy outcome, and in utero transmission of the microorganism to the fetus. Mycoplasma pulmonis is an ideal model to study maternal genital infection during pregnancy, the impact of infections on pregnancy outcome, fetal infection, and maternal-fetal immune interactions.

  15. Combating Combination of Hypertension and Diabetes in Different Rat Models

    Directory of Open Access Journals (Sweden)

    Talma Rosenthal

    2010-03-01

    Full Text Available Rat experimental models are used extensively for studying physiological mechanisms and treatments of hypertension and diabetes co-existence. Each one of these conditions is a major risk factor for cardiovascular disease (CVD, and the combination of the two conditions is a potent enhancer of CVD. Five major animal models that advanced our understanding of the mechanisms and therapeutic approaches in humans are discussed in this review: Zucker, Goto-Kakizaki, SHROB, SHR/NDmcr-cp and Cohen Rosenthal diabetic hypertensive (CRDH rats. The use of various drugs, such as angiotensin-converting enzyme (ACE inhibitors (ACEIs, various angiotensin receptor blockers (ARBs, and calcium channel blockers (CCBs, to combat the effects of concomitant pathologies on the combination of diabetes and hypertension, as well as the non-pharmacological approach are reviewed in detail for each rat model. Results from experiments on these models indicate that classical factors contributing to the pathology of hypertension and diabetes combination—Including hypertension, hyperglycemia, hyperinsulinemia and hyperlipidemia—can now be treated, although these treatments do not completely prevent renal complications. Animal studies have focused on several mechanisms involved in hypertension/diabetes that remain to be translated into clinical medicine, including hypoxia, oxidative stress, and advanced glycation. Several target molecules have been identified that need to be incorporated into a treatment modality. The challenge continues to be the identification and interpretation of the clinical evidence from the animal models and their application to human treatment.

  16. Research on lightning stroke model and characteristics of electronic transformer

    Directory of Open Access Journals (Sweden)

    Li Mu

    2018-01-01

    Full Text Available In order to improve the reliability of power supply, a large number of electronic voltage and current transformers are used in digital substations. In this paper, the mathematical model of the electronic transformer is analyzed firstly, and its circuit model is given. According to the difference of working characteristics between voltage transformer and current transformer, the circuit model of voltage type electronic transformer and current type electronic transformer is given respectively. By analyzing their broadband transmission characteristics, the accuracy of the model is verified, and their lightning analysis models are obtained.

  17. Prevention of injury by resveratrol in a rat model of adenine-induced ...

    African Journals Online (AJOL)

    phosphorous, and fibroblast growth factor-23 (FGF-23) in rat urine samples after 2 months of adenine ... parathyroid hormone, phosphorous and FGF-23 levels (p < 0.002). In rats ... cartilage degradation in animal models of arthritis. [11].

  18. Protective effects of Naringin in a rat model of spinal cord ischemia ...

    African Journals Online (AJOL)

    generation and downregulating inflammatory markers in an SCI rat model. Keywords: Naringin ... intestinal microflora to yield a metabolite called naringenin ... disease (PD). Moreover .... CAT was significantly reduced in SCII rats compared ...

  19. Free radicals imaged in vivo in the rat by using proton-electron double-resonance imaging

    International Nuclear Information System (INIS)

    Lurie, D.J.; Nicholson, Ian; Foster, M.A.; Mallard, J.R.

    1990-01-01

    A new technique called proton-electron double-resonance imaging is described for imaging free radicals in aqueous samples. The method is a combination of proton NMR imaging with nuclear electron double resonance. The results of using this technique to image free radicals in vivo in the rat are presented. Rats were injected intravenously with a nitroxide free radical solution and a series of images was obtained from which the clearance of the free radical through the liver and kidneys could be observed. (author)

  20. Electron Model of Linear-Field FFAG

    CERN Document Server

    Koscielniak, Shane R

    2005-01-01

    A fixed-field alternating-gradient accelerator (FFAG) that employs only linear-field elements ushers in a new regime in accelerator design and dynamics. The linear-field machine has the ability to compact an unprecedented range in momenta within a small component aperture. With a tune variation which results from the natural chromaticity, the beam crosses many strong, uncorrec-table, betatron resonances during acceleration. Further, relativistic particles in this machine exhibit a quasi-parabolic time-of-flight that cannot be addressed with a fixed-frequency rf system. This leads to a new concept of bucketless acceleration within a rotation manifold. With a large energy jump per cell, there is possibly strong synchro-betatron coupling. A few-MeV electron model has been proposed to demonstrate the feasibility of these untested acceleration features and to investigate them at length under a wide range of operating conditions. This paper presents a lattice optimized for a 1.3 GHz rf, initial technology choices f...

  1. A comparative behavioural study of mechanical hypersensitivity in 2 pain models in rats and humans.

    Science.gov (United States)

    Reitz, Marie-Céline; Hrncic, Dragan; Treede, Rolf-Detlef; Caspani, Ombretta

    2016-06-01

    The assessment of pain sensitivity in humans has been standardized using quantitative sensory testing, whereas in animals mostly paw withdrawal thresholds to diverse stimuli are measured. This study directly compares tests used in quantitative sensory testing (pinpricks, pressure algometer) with tests used in animal studies (electronic von Frey test: evF), which we applied to the dorsal hind limbs of humans after high frequency stimulation and rats after tibial nerve transection. Both experimental models induce profound mechanical hypersensitivity. At baseline, humans and rats showed a similar sensitivity to evF with 0.2 mm diameter tips, but significant differences for other test stimuli (all P pain models (P pain sensitivity, but probe size and shape should be standardized. Hypersensitivity to blunt pressure-the leading positive sensory sign after peripheral nerve injury in humans-is a novel finding in the tibial nerve transection model. By testing outside the primary zone of nerve damage (rat) or activation (humans), our methods likely involve effects of central sensitization in both species.

  2. Establishment of reproducible osteosarcoma rat model using orthotopic implantation technique.

    Science.gov (United States)

    Yu, Zhe; Sun, Honghui; Fan, Qingyu; Long, Hua; Yang, Tongtao; Ma, Bao'an

    2009-05-01

    In experimental musculoskeletal oncology, there remains a need for animal models that can be used to assess the efficacy of new and innovative treatment methodologies for bone tumors. Rat plays a very important role in the bone field especially in the evaluation of metabolic bone diseases. The objective of this study was to develop a rat osteosarcoma model for evaluation of new surgical and molecular methods of treatment for extremity sarcoma. One hundred male SD rats weighing 125.45+/-8.19 g were divided into 5 groups and anesthetized intraperitoneally with 10% chloral hydrate. Orthotopic implantation models of rat osteosarcoma were performed by injecting directly into the SD rat femur with a needle for inoculation with SD tumor cells. In the first step of the experiment, 2x10(5) to 1x10(6) UMR106 cells in 50 microl were injected intraosseously into median or distal part of the femoral shaft and the tumor take rate was determined. The second stage consisted of determining tumor volume, correlating findings from ultrasound with findings from necropsia and determining time of survival. In the third stage, the orthotopically implanted tumors and lung nodules were resected entirely, sectioned, and then counter stained with hematoxylin and eosin for histopathologic evaluation. The tumor take rate was 100% for implants with 8x10(5) tumor cells or more, which was much less than the amount required for subcutaneous implantation, with a high lung metastasis rate of 93.0%. Ultrasound and necropsia findings matched closely (r=0.942; p<0.01), which demonstrated that Doppler ultrasonography is a convenient and reliable technique for measuring cancer at any stage. Tumor growth curve showed that orthotopically implanted tumors expanded vigorously with time-lapse, especially in the first 3 weeks. The median time of survival was 38 days and surgical mortality was 0%. The UMR106 cell line has strong carcinogenic capability and high lung metastasis frequency. The present rat

  3. Creation of Consistent Burn Wounds: A Rat Model

    Directory of Open Access Journals (Sweden)

    Elijah Zhengyang Cai

    2014-07-01

    Full Text Available Background Burn infliction techniques are poorly described in rat models. An accurate study can only be achieved with wounds that are uniform in size and depth. We describe a simple reproducible method for creating consistent burn wounds in rats. Methods Ten male Sprague-Dawley rats were anesthetized and dorsum shaved. A 100 g cylindrical stainless-steel rod (1 cm diameter was heated to 100℃ in boiling water. Temperature was monitored using a thermocouple. We performed two consecutive toe-pinch tests on different limbs to assess the depth of sedation. Burn infliction was limited to the loin. The skin was pulled upwards, away from the underlying viscera, creating a flat surface. The rod rested on its own weight for 5, 10, and 20 seconds at three different sites on each rat. Wounds were evaluated for size, morphology and depth. Results Average wound size was 0.9957 cm2 (standard deviation [SD] 0.1845 (n=30. Wounds created with duration of 5 seconds were pale, with an indistinct margin of erythema. Wounds of 10 and 20 seconds were well-defined, uniformly brown with a rim of erythema. Average depths of tissue damage were 1.30 mm (SD 0.424, 2.35 mm (SD 0.071, and 2.60 mm (SD 0.283 for duration of 5, 10, 20 seconds respectively. Burn duration of 5 seconds resulted in full-thickness damage. Burn duration of 10 seconds and 20 seconds resulted in full-thickness damage, involving subjacent skeletal muscle. Conclusions This is a simple reproducible method for creating burn wounds consistent in size and depth in a rat burn model.

  4. Analytic model of electron pulse propagation in ultrafast electron diffraction experiments

    International Nuclear Information System (INIS)

    Michalik, A.M.; Sipe, J.E.

    2006-01-01

    We present a mean-field analytic model to study the propagation of electron pulses used in ultrafast electron diffraction experiments (UED). We assume a Gaussian form to characterize the electron pulse, and derive a system of ordinary differential equations that are solved quickly and easily to give the pulse dynamics. We compare our model to an N-body numerical simulation and are able to show excellent agreement between the two result sets. This model is a convenient alternative to time consuming and computationally intense N-body simulations in exploring the dynamics of UED electron pulses, and as a tool for refining UED experimental designs

  5. induced cerebral injury in a rat model

    African Journals Online (AJOL)

    Results: There was a significant decrease in neurological deficit, brain oedema, and volume of ... This is an Open Access article that uses a funding model which does not charge readers or .... Moreover, the percentage of infarct volume was.

  6. The electronic-commerce-oriented virtual merchandise model

    Science.gov (United States)

    Fang, Xiaocui; Lu, Dongming

    2004-03-01

    Electronic commerce has been the trend of commerce activities. Providing with Virtual Reality interface, electronic commerce has better expressing capacity and interaction means. But most of the applications of virtual reality technology in EC, 3D model is only the appearance description of merchandises. There is almost no information concerned with commerce information and interaction information. This resulted in disjunction of virtual model and commerce information. So we present Electronic Commerce oriented Virtual Merchandise Model (ECVMM), which combined a model with commerce information, interaction information and figure information of virtual merchandise. ECVMM with abundant information provides better support to information obtainment and communication in electronic commerce.

  7. Ideal Experimental Rat Models for Liver Diseases

    OpenAIRE

    Lee, Sang Woo; Kim, Sung Hoon; Min, Seon Ok; Kim, Kyung Sik

    2011-01-01

    There are many limitations for conducting liver disease research in human beings due to the high cost and potential ethical issues. For this reason, conducting a study that is difficult to perform in humans using appropriate animal models, can be beneficial in ascertaining the pathological physiology, and in developing new treatment modalities. However, it is difficult to determine the appropriate animal model which is suitable for research purposes, since every patient has different and dive...

  8. Lessons on electronic decoherence in molecules from exact modeling

    Science.gov (United States)

    Hu, Wenxiang; Gu, Bing; Franco, Ignacio

    2018-04-01

    Electronic decoherence processes in molecules and materials are usually thought and modeled via schemes for the system-bath evolution in which the bath is treated either implicitly or approximately. Here we present computations of the electronic decoherence dynamics of a model many-body molecular system described by the Su-Schrieffer-Heeger Hamiltonian with Hubbard electron-electron interactions using an exact method in which both electronic and nuclear degrees of freedom are taken into account explicitly and fully quantum mechanically. To represent the electron-nuclear Hamiltonian in matrix form and propagate the dynamics, the computations employ the Jordan-Wigner transformation for the fermionic creation/annihilation operators and the discrete variable representation for the nuclear operators. The simulations offer a standard for electronic decoherence that can be used to test approximations. They also provide a useful platform to answer fundamental questions about electronic decoherence that cannot be addressed through approximate or implicit schemes. Specifically, through simulations, we isolate basic mechanisms for electronic coherence loss and demonstrate that electronic decoherence is possible even for one-dimensional nuclear bath. Furthermore, we show that (i) decreasing the mass of the bath generally leads to faster electronic decoherence; (ii) electron-electron interactions strongly affect the electronic decoherence when the electron-nuclear dynamics is not pure-dephasing; (iii) classical bath models with initial conditions sampled from the Wigner distribution accurately capture the short-time electronic decoherence dynamics; (iv) model separable initial superpositions often used to understand decoherence after photoexcitation are only relevant in experiments that employ delta-like laser pulses to initiate the dynamics. These insights can be employed to interpret and properly model coherence phenomena in molecules.

  9. RAMAN LIGHT SCATTERING IN PSEUDOSPIN-ELECTRON MODEL AT STRONG PSEUDOSPIN-ELECTRON INTERACTION

    Directory of Open Access Journals (Sweden)

    T.S.Mysakovych

    2004-01-01

    Full Text Available Anharmonic phonon contributions to Raman scattering in locally anharmonic crystal systems in the framework of the pseudospin-electron model with tunneling splitting of levels are investigated. The case of strong pseudospin-electron coupling is considered. Pseudospin and electron contributions to scattering are taken into account. Frequency dependences of Raman scattering intensity for different values of model parameters and for different polarization of scattering and incident light are investigated.

  10. The concentration of kynurenine in rat model of asthma.

    Directory of Open Access Journals (Sweden)

    Barbara Mroczko

    2008-06-01

    Full Text Available Asthma is a chronic inflammatory disease that involves the immune system activation. Evidence is accumulating about the role of kynurenine pathway in the immune system regulation. The kynurenine pathway includes several metabolites of tryptophan, among others kynurenine (KYN. To study the immunological system regulation in asthma a simple and sensitive models of asthma are required. In the present study we induced rat model of asthma using ovalbumin (OVA sensitization followed by challenge with OVA. The development of asthma has been confirmed by plasma total IgE measurement and the histological examination. The concentration of KYN has been determined in plasma, lungs and liver by high-performance liquid chromatography (HPLC. In OVA sensitized rats the concentration of total IgE was statistically significantly increased as compared to VEH sensitized control groups (437.6 +/- 97.7 kU/l vs 159.2 +/- 22.7 kU/l, respectively; p< 0.01. In asthmatic animals, the number of eosinophils, neutrophils and mast cells increased considerably, and epithelial lesion and the increase in airway epithelium goblet cells and edema of bronchial mucosa were present. We did not observe any significant changes in the concentration of KYN in plasma, lungs or liver between studied groups. In conclusion, the concentration of KYN remains unchanged in asthmatic animals as compared to control groups. Further studies using rat model of asthma are warranted to establish the role of kynurenine pathway regulation in asthma.

  11. Aerosol Infection Model of Tuberculosis in Wistar Rats

    Directory of Open Access Journals (Sweden)

    Sheshagiri Gaonkar

    2010-01-01

    Full Text Available We explored suitability of a rat tuberculosis aerosol infection model for investigating the pharmacodynamics of new antimycobacterial agents. Infection of rats via the aerosol route led to a reproducible course of M. tuberculosis infection in the lungs. The pulmonary bacterial load increased logarithmically during the first six weeks, thereafter, the infection stabilized for the next 12 weeks. We observed macroscopically visible granulomas in the lungs with demonstrable acid-fast bacilli and associated histopathology. Rifampicin (RIF at a dose range of 30 to 270 mg/kg exhibited a sharp dose response while isoniazid (INH at a dose range of 10 to 90 mg/kg and ethambutol (EMB at 100 to 1000 mg/kg showed shallow dose responses. Pyrazinamide (PZA had no dose response between 300 and 1000 mg/kg dose range. In a separate time kill study at fixed drug doses (RIF 90 mg/kg, INH 30 mg/kg, EMB 300 mg/kg, and PZA 300 mg/kg the bactericidal effect of all the four drugs increased with longer duration of treatment from two weeks to four weeks. The observed infection profile and therapeutic outcomes in this rat model suggest that it can be used as an additional, pharmacologically relevant efficacy model to develop novel antitubercular compounds at the interface of discovery and development.

  12. Experimental rat lung tumor model with intrabronchial tumor cell implantation.

    Science.gov (United States)

    Gomes Neto, Antero; Simão, Antônio Felipe Leite; Miranda, Samuel de Paula; Mourão, Lívia Talita Cajaseiras; Bezerra, Nilfácio Prado; Almeida, Paulo Roberto Carvalho de; Ribeiro, Ronaldo de Albuquerque

    2008-01-01

    The objective of this study was to develop a rat lung tumor model for anticancer drug testing. Sixty-two female Wistar rats weighing 208 +/- 20 g were anesthetized intraperitoneally with 2.5% tribromoethanol (1 ml/100 g live weight), tracheotomized and intubated with an ultrafine catheter for inoculation with Walker's tumor cells. In the first step of the experiment, a technique was established for intrabronchial implantation of 10(5) to 5 x 10(5) tumor cells, and the tumor take rate was determined. The second stage consisted of determining tumor volume, correlating findings from high-resolution computed tomography (HRCT) with findings from necropsia and determining time of survival. The tumor take rate was 94.7% for implants with 4 x 10(5) tumor cells, HRCT and necropsia findings matched closely (r=0.953; p<0.0001), the median time of survival was 11 days, and surgical mortality was 4.8%. The present rat lung tumor model was shown to be feasible: the take rate was high, surgical mortality was negligible and the procedure was simple to perform and easily reproduced. HRCT was found to be a highly accurate tool for tumor diagnosis, localization and measurement and may be recommended for monitoring tumor growth in this model.

  13. The Fischer 344 rat as a model of presbycusis.

    Science.gov (United States)

    Syka, Josef

    2010-06-01

    Due to the rising number of the aged human population all over the world, presbycusis is a phenomenon that deserves the increasing attention of the medical community as regards to prevention and treatment. This requires finding appropriate animal models for human presbycusis that will be useful in future experiments. Among the available rat strains, the Fischer 344 (F344) strain promises to serve as a model producing prompt and profound presbycusis. Hearing thresholds begin to increase in this strain during the first year of life; toward the end of the second year, the thresholds are very high. The threshold shifts progress independently in both ears. The rapid deterioration of distortion product otoacoustic emissions, with the majority of outer hair cells (OHC) being present and morphologically intact, is apparently produced by the disruption of prestin. The age-related changes within inner ear function are accompanied by deterioration of acoustical signal processing within central auditory system, mainly due to impaired GABA inhibition. The loss of GABA inhibition in old animals is expressed primarily in the inferior colliculus but is also present in the cochlear nuclei and the auditory cortex. Sound-evoked behavioral reactions are also impaired in old F344 rats. Taken together, the described characteristics of the aging F344 rat auditory system supports the idea that this strain may serve as a suitable model for studying the mechanisms of presbycusis, its prevention and treatment. Copyright 2009 Elsevier B.V. All rights reserved.

  14. Mathematical model of glucose-insulin homeostasis in healthy rats.

    Science.gov (United States)

    Lombarte, Mercedes; Lupo, Maela; Campetelli, German; Basualdo, Marta; Rigalli, Alfredo

    2013-10-01

    According to the World Health Organization there are over 220 million people in the world with diabetes and 3.4 million people died in 2004 as a consequence of this pathology. Development of an artificial pancreas would allow to restore control of blood glucose by coupling an infusion pump to a continuous glucose sensor in the blood. The design of such a device requires the development and application of mathematical models which represent the gluco-regulatory system. Models developed by other research groups describe very well the gluco-regulatory system but have a large number of mathematical equations and require complex methodologies for the estimation of its parameters. In this work we propose a mathematical model to study the homeostasis of glucose and insulin in healthy rats. The proposed model consists of three differential equations and 8 parameters that describe the variation of: blood glucose concentration, blood insulin concentration and amount of glucose in the intestine. All parameters were obtained by setting functions to the values of glucose and insulin in blood obtained after oral glucose administration. In vivo and in silico validations were performed. Additionally, a qualitative analysis has been done to verify the aforementioned model. We have shown that this model has a single, biologically consistent equilibrium point. This model is a first step in the development of a mathematical model for the type I diabetic rat. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Monoenergetic electron parameters in a spheroid bubble model

    Science.gov (United States)

    Sattarian, H.; Sh., Rahmatallahpur; Tohidi, T.

    2013-02-01

    A reliable analytical expression for the potential of plasma waves with phase velocities near the speed of light is derived. The presented spheroid cavity model is more consistent than the previous spherical and ellipsoidal models and it explains the mono-energetic electron trajectory more accurately, especially at the relativistic region. The maximum energy of electrons is calculated and it is shown that the maximum energy of the spheroid model is less than that of the spherical model. The electron energy spectrum is also calculated and it is found that the energy distribution ratio of electrons ΔE/E for the spheroid model under the conditions reported here is half that of the spherical model and it is in good agreement with the experimental value in the same conditions. As a result, the quasi-mono-energetic electron output beam interacting with the laser plasma can be more appropriately described with this model.

  16. Monoenergetic electron parameters in a spheroid bubble model

    International Nuclear Information System (INIS)

    Sattarian, H.; Rahmatallahpur, Sh.; Tohidi, T.

    2013-01-01

    A reliable analytical expression for the potential of plasma waves with phase velocities near the speed of light is derived. The presented spheroid cavity model is more consistent than the previous spherical and ellipsoidal models and it explains the mono-energetic electron trajectory more accurately, especially at the relativistic region. The maximum energy of electrons is calculated and it is shown that the maximum energy of the spheroid model is less than that of the spherical model. The electron energy spectrum is also calculated and it is found that the energy distribution ratio of electrons ΔE/E for the spheroid model under the conditions reported here is half that of the spherical model and it is in good agreement with the experimental value in the same conditions. As a result, the quasi-mono-energetic electron output beam interacting with the laser plasma can be more appropriately described with this model. (physics of gases, plasmas, and electric discharges)

  17. An electron microscopic studies of radiation effects on the enamel development of the rat molar

    International Nuclear Information System (INIS)

    Cho, Hyo Suck; Yoo, Dong Soo

    1995-01-01

    Mandibular first molars of the rats were undertaken to observe the radiosensitivity of amelogenesis. Twenty four Sprague-Dawley rats received 396cGy radiation with the MK Cell irradiator using Cs-137, and twenty four rats served as control. They were divided into two groups; Group 1 which received radiation at the 14th day after gestation and group 2 which received radiation at the 19th day after gestation. Light Microscopy and Transmitted Electron Microscopy investigation was undertaken in the group 1 at the 15th, 18th, 20th, 22nd (2 days after birth), and 25th day (5 days after birth) after gestation, and in the group Z at the 21th (birth day), 22nd (2 days after birth), and 25th (5 days after birth) day after gestation. The following histopathologic findings were obtained. 1. Compared with control group, experimental group showed a delayed formation of enamel and dentin due to slow rate of differentiation of undifferentiated mesenchymal cells. 2. In the experimental groups, the arrangement of the inner enamel epithelium was irregular and there were many vacuoles in the cytoplasm. There were dilated rER and mitochondria, increase of the intercellular space, and loss of the cellular polarity. 3. In the group 1, early enamel without Tomes' process, and early organic matrix was observed at the 25th day after gestation. 4. In the group 2, histopathologic changes were similar to those of the group 1, but the degree of changes was more severe than that of the group l.

  18. An electron microscopic studies of radiation effects on the enamel development of the rat molar

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hyo Suck; Yoo, Dong Soo [Dept. of Oral and Maxillofacial Radiology, Graduate School, Seoul National University, Seoul (Korea, Republic of)

    1995-08-15

    Mandibular first molars of the rats were undertaken to observe the radiosensitivity of amelogenesis. Twenty four Sprague-Dawley rats received 396cGy radiation with the MK Cell irradiator using Cs-137, and twenty four rats served as control. They were divided into two groups; Group 1 which received radiation at the 14th day after gestation and group 2 which received radiation at the 19th day after gestation. Light Microscopy and Transmitted Electron Microscopy investigation was undertaken in the group 1 at the 15th, 18th, 20th, 22nd (2 days after birth), and 25th day (5 days after birth) after gestation, and in the group Z at the 21th (birth day), 22nd (2 days after birth), and 25th (5 days after birth) day after gestation. The following histopathologic findings were obtained. 1. Compared with control group, experimental group showed a delayed formation of enamel and dentin due to slow rate of differentiation of undifferentiated mesenchymal cells. 2. In the experimental groups, the arrangement of the inner enamel epithelium was irregular and there were many vacuoles in the cytoplasm. There were dilated rER and mitochondria, increase of the intercellular space, and loss of the cellular polarity. 3. In the group 1, early enamel without Tomes' process, and early organic matrix was observed at the 25th day after gestation. 4. In the group 2, histopathologic changes were similar to those of the group 1, but the degree of changes was more severe than that of the group l.

  19. A rat model for embolic encephalitis

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Rasmussen, Rune Skovgaard; Aalbæk, Bent

    2011-01-01

    have recently shown that sepsis is a common cause of microabscesses in the brain, and that S. aureus is one of the most common organisms isolated from these abscesses. This raises the question whether the blood-brain barrier truly makes the brain an immune-privileged organ or not. This makes the brain...... a most interesting organ in sepsis patients. However, symptoms of brain infection may be confused with systemic responses and gross neuropathologic lesions may be absent. Brain infection in sepsis patients is therefore prone to misclassification or diagnostic delay, and when the diagnosis is made...... it is difficult to obtain tissue for further examination. This puts a hard demand on animal models of brain lesions in sepsis. We hereby present a novel animal model of embolic encephalitis. Our model introduces bacteria by an embolus to an area of brain necrosis and damage to the blood-brain...

  20. GGF2 is neuroprotective in a rat model of cavernous nerve injury-induced erectile dysfunction.

    Science.gov (United States)

    Burnett, Arthur L; Sezen, Sena F; Hoke, Ahmet; Caggiano, Anthony O; Iaci, Jennifer; Lagoda, Gwen; Musicki, Biljana; Bella, Anthony J

    2015-04-01

    Erectile dysfunction is a major complication of radical prostatectomy, commonly associated with penile neuropathy. In animal models of peripheral nerve injury, glial growth factor-2 (GGF2), a member of the neuregulin family of growth factors, has neuroprotective and neurorestorative properties, but this potential has not been established after cavernous nerve (CN) injury. The effectiveness of GGF2 in preserving axonal integrity and recovering erectile function in a rat model of radical prostatectomy-associated CN injury. Adult male Sprague-Dawley rats underwent bilateral CN crush injury (BCNI) or sham surgery. Rats were administered GGF2 (0.5, 5, or 15 mg/kg) or vehicle subcutaneously 24 hour pre and 24-hour post-BCNI, and once weekly for 5 weeks. Erectile function was assessed in response to electrical stimulation of the CN. CN survival was assessed by fluorogold retrograde axonal tracing in major pelvic ganglia (MPG). Unmyelinated axons in the CNs were quantitated by electron microscopy. Erectile function recovery, CN survival, and unmyelinated CN axon preservation in response to GGF2 treatment following BCNI. Erectile function was decreased (P cells in the MPG was reduced (P Schwann cells in the BCNI group was higher (P Schwann cell compared with the BCNI group. GGF2 promotes erectile function recovery following CN injury in conjunction with preserving unmyelinated CN fibers. Our findings suggest the clinical opportunity to develop GGF2 as a neuroprotective therapy for radical prostatectomy. © 2015 International Society for Sexual Medicine.

  1. Reduction of mitochondrial electron transport complex activity is restricted to the ischemic focus after transient focal cerebral ischemia in rats

    DEFF Research Database (Denmark)

    Christensen, Thomas; Diemer, Nils Henrik

    2003-01-01

    Using histochemical methods offering high topographical resolution for evaluation of changes in the ischemic focus and the penumbra, the mitochondrial electron transport chain (ETC) complexes I, II, and IV were examined in rats subjected to 2 h of proximal occlusion of the middle cerebral artery...

  2. On the Localisation of d-Tubocurarine in Rat Liver Lysosomes in vivo by Electron Microscopy and Subcellular Fractionation

    NARCIS (Netherlands)

    Weitering, Jeanette G.; Mulder, Gerard J.; Meijer, Dirk K.F.; Lammers, Wim; Veenhuis, Maarten; Wendelaar Bonga, Sjoerd E.

    1975-01-01

    After i.v. injection in the rat, d-tubocurarine is taken up and concentrated by the liver. A method is developed for the visualisation of d-tubocurarine inside the liver cell by electron microscopy. Glutaraldehyde fixed liver blocks were immersed in an ammonium molybdate solution; d-tubocurarine was

  3. Modeling the mechanical properties of liver fibrosis in rats.

    Science.gov (United States)

    Zhu, Ying; Chen, Xin; Zhang, Xinyu; Chen, Siping; Shen, Yuanyuan; Song, Liang

    2016-06-14

    The progression of liver fibrosis changes the biomechanical properties of liver tissue. This study characterized and compared different liver fibrosis stages in rats in terms of viscoelasticity. Three viscoelastic models, the Voigt, Maxwell, and Zener models, were applied to experimental data from rheometer tests and then the elasticity and viscosity were estimated for each fibrosis stage. The study found that both elasticity and viscosity are correlated with the various stages of liver fibrosis. The study revealed that the Zener model is the optimal model for describing the mechanical properties of each fibrosis stage, but there is no significant difference between the Zener and Voigt models in their performance on liver fibrosis staging. Therefore the Voigt model can still be effectively used for liver fibrosis grading. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. A kinetic model for runaway electrons in the ionosphere

    Directory of Open Access Journals (Sweden)

    G. Garcia

    2006-09-01

    Full Text Available Electrodynamic models and measurements with satellites and incoherent scatter radars predict large field aligned current densities on one side of the auroral arcs. Different authors and different kinds of studies (experimental or modeling agree that the current density can reach up to hundreds of µA/m2. This large current density could be the cause of many phenomena such as tall red rays or triggering of unstable ion acoustic waves. In the present paper, we consider the issue of electrons moving through an ionospheric gas of positive ions and neutrals under the influence of a static electric field. We develop a kinetic model of collisions including electrons/electrons, electrons/ions and electrons/neutrals collisions. We use a Fokker-Planck approach to describe binary collisions between charged particles with a long-range interaction. We present the essential elements of this collision operator: the Langevin equation for electrons/ions and electrons/electrons collisions and the Monte-Carlo and null collision methods for electrons/neutrals collisions. A computational example is given illustrating the approach to equilibrium and the impact of the different terms (electrons/electrons and electrons/ions collisions on the one hand and electrons/neutrals collisions on the other hand. Then, a parallel electric field is applied in a new sample run. In this run, the electrons move in the z direction parallel to the electric field. The first results show that all the electron distribution functions are non-Maxwellian. Furthermore, runaway electrons can carry a significant part of the total current density, up to 20% of the total current density.

  5. A kinetic model for runaway electrons in the ionosphere

    Directory of Open Access Journals (Sweden)

    G. Garcia

    2006-09-01

    Full Text Available Electrodynamic models and measurements with satellites and incoherent scatter radars predict large field aligned current densities on one side of the auroral arcs. Different authors and different kinds of studies (experimental or modeling agree that the current density can reach up to hundreds of µA/m2. This large current density could be the cause of many phenomena such as tall red rays or triggering of unstable ion acoustic waves. In the present paper, we consider the issue of electrons moving through an ionospheric gas of positive ions and neutrals under the influence of a static electric field. We develop a kinetic model of collisions including electrons/electrons, electrons/ions and electrons/neutrals collisions. We use a Fokker-Planck approach to describe binary collisions between charged particles with a long-range interaction. We present the essential elements of this collision operator: the Langevin equation for electrons/ions and electrons/electrons collisions and the Monte-Carlo and null collision methods for electrons/neutrals collisions. A computational example is given illustrating the approach to equilibrium and the impact of the different terms (electrons/electrons and electrons/ions collisions on the one hand and electrons/neutrals collisions on the other hand. Then, a parallel electric field is applied in a new sample run. In this run, the electrons move in the z direction parallel to the electric field. The first results show that all the electron distribution functions are non-Maxwellian. Furthermore, runaway electrons can carry a significant part of the total current density, up to 20% of the total current density.

  6. FTL Quantum Models of the Photon and the Electron

    International Nuclear Information System (INIS)

    Gauthier, Richard F.

    2007-01-01

    A photon is modeled by an uncharged superluminal quantum moving at 1.414c along an open 45-degree helical trajectory with radius R = λ/2π (where λ is the helical pitch or wavelength). A mostly superluminal spatial model of an electron is composed of a charged pointlike quantum circulating at an extremely high frequency ( 2.5 x 1020 hz) in a closed, double-looped hehcal trajectory whose helical pitch is one Compton wavelength h/mc. The quantum has energy and momentum but not rest mass, so its speed is not limited by c. sThe quantum's speed is superluminal 57% of the time and subluminal 43% of the time, passing through c twice in each trajectory cycle. The quantum's maximum speed in the electron's rest frame is 2.515c and its minimum speed is .707c. The electron model's helical trajectory parameters are selected to produce the electron's spin (ℎ/2π)/2 and approximate (without small QED corrections) magnetic moment e(ℎ/2π)/2m (the Bohr magneton μB) as well as its Dirac equation-related 'jittery motion' angular frequency 2mc2/(ℎ/2π), amplitude (ℎ/2π)/2mc and internal speed c. The two possible helicities of the electron model correspond to the electron and the positron. With these models, an electron is like a closed circulating photon. The electron's inertia is proposed to be related to the electron model's circulating internal Compton momentum mc. The internal superluminalily of the photon model, the internal superluminahty/subluminality of the electron model, and the proposed approach to the electron's inertia as ''momentum at rest'' within the electron, could be relevant to possible mechanisms of superluminal communication and transportation

  7. Phase-Space Models of Solitary Electron Hoies

    DEFF Research Database (Denmark)

    Lynov, Jens-Peter; Michelsen, Poul; Pécseli, Hans

    1985-01-01

    Two different phase-space models of solitary electron holes are investigated and compared with results from computer simulations of an actual laboratory experiment, carried out in a strongly magnetized, cylindrical plasma column. In the two models, the velocity distribution of the electrons...

  8. A Rat Model for Muscle Regeneration in the Soft Palate

    Science.gov (United States)

    Carvajal Monroy, Paola L.; Grefte, Sander; Kuijpers-Jagtman, Anne M.; Helmich, Maria P. A. C.; Ulrich, Dietmar J. O.; Von den Hoff, Johannes W.; Wagener, Frank A. D. T. G.

    2013-01-01

    Background Children with a cleft in the soft palate have difficulties with speech, swallowing, and sucking. Despite successful surgical repositioning of the muscles, optimal function is often not achieved. Scar formation and defective regeneration may hamper the functional recovery of the muscles after cleft palate repair. Therefore, the aim of this study is to investigate the anatomy and histology of the soft palate in rats, and to establish an in vivo model for muscle regeneration after surgical injury. Methods Fourteen adult male Sprague Dawley rats were divided into four groups. Groups 1 (n = 4) and 2 (n = 2) were used to investigate the anatomy and histology of the soft palate, respectively. Group 3 (n = 6) was used for surgical wounding of the soft palate, and group 4 (n = 2) was used as unwounded control group. The wounds (1 mm) were evaluated by (immuno)histochemistry (AZAN staining, Pax7, MyoD, MyoG, MyHC, and ASMA) after 7 days. Results The present study shows that the anatomy and histology of the soft palate muscles of the rat is largely comparable with that in humans. All wounds showed clinical evidence of healing after 7 days. AZAN staining demonstrated extensive collagen deposition in the wound area, and initial regeneration of muscle fibers and salivary glands. Proliferating and differentiating satellite cells were identified in the wound area by antibody staining. Conclusions This model is the first, suitable for studying muscle regeneration in the rat soft palate, and allows the development of novel adjuvant strategies to promote muscle regeneration after cleft palate surgery. PMID:23554995

  9. Molecular modeling and multiscaling issues for electronic material applications

    CERN Document Server

    Iwamoto, Nancy; Yuen, Matthew; Fan, Haibo

    Volume 1 : Molecular Modeling and Multiscaling Issues for Electronic Material Applications provides a snapshot on the progression of molecular modeling in the electronics industry and how molecular modeling is currently being used to understand material performance to solve relevant issues in this field. This book is intended to introduce the reader to the evolving role of molecular modeling, especially seen through the eyes of the IEEE community involved in material modeling for electronic applications.  Part I presents  the role that quantum mechanics can play in performance prediction, such as properties dependent upon electronic structure, but also shows examples how molecular models may be used in performance diagnostics, especially when chemistry is part of the performance issue.  Part II gives examples of large-scale atomistic methods in material failure and shows several examples of transitioning between grain boundary simulations (on the atomistic level)and large-scale models including an example ...

  10. Effect of sildenafil citrate (Viagra) and ethanol on the Albino rat testis: a scanning electron microscopic approach.

    Science.gov (United States)

    Sivasankaran, T G; Udayakumar, R; Elanchezhiyan, C; Sabhanayakam, Selvi

    2008-02-01

    The effects of sildenafil citrate with ethanol on the rat testis was studied using scanning electron microscopy. Male Albino rats were divided into 8 groups, each being treated for a maximum of 45 days as follows. In the 4 short-term treatment groups, control rats were administered normal saline orally, whereas experimental animals were fed sildenafil citrate (Viagra) 1 microg/g with 18% ethanol (5 g/kg body weight), which was given orally as a single dose. After 1, 2.5, 4 and 24h the rats were killed. In the 4 long-term treatment groups, daily continuous doses of drug and ethanol with a single dosage were given for 15, 30 and 45 days and the animals killed 4h after the last dosage. Changes in the testis were compared with the normal healthy rat testis. The use of a scanning electron microscope for evaluation of the changes in the testis is more suitable for observation of the surface and morphological shapes of the tissue structures.

  11. [Establishment of rat model with diabetes mellitus and concomitant periodontitis and the carotid artery lesions in the model rats].

    Science.gov (United States)

    Ren, X Y; Wang, C; Liu, X; Li, H; Gao, J H; Ge, X J

    2017-12-09

    Objectives: To establish SD rat model with type 2 diabetes mellitus (DM) and concomitant chronic periodontitis (CP) and to evaluate the influence of periodontitis on the vascular lesions of type 2 diabetes rats. Methods: Totally 241 clean level SD rats were randomly divided into four groups, group A (normal control, NC, n= 27), group B (DM, n= 34), group C (CP, n= 90) and group D (DM+CP, n= 90). The rats of DM group were fed with high-fat and high-sugar diet for 8 to 10 weeks, and then were multiply injected with small dose streptozotocin under the condition of ice bath. Blood sugar levels after the injection were dynamically monitored at 72 h, 1 week, 2 weeks and 4 weeks, respectively. The CP model was established by means of ligation. Bilateral maxillary first and second molars were selected and ligated using 0.2 mm orthodontic wires binding with 4-0 surgical suture soaked with Porphyromonas gingivalis (Pg) suspension. After a period of 14 weeks, all the rats were put to death. Maxillary samples were subjected to methylene blue staining to observe alveolar bone loss. Bilateral carotid artery specimens were collected. The left carotid artery specimens were used to detect the prevalence of Pg using quantitative real-time PCR. The right carotid artery specimens were used to observe pathological changes. Results: Blood sugar levels of rats in group B and D increased and changed sharply after Streptozotocin injection with in 1 week. Symptoms of 'more drink, more food and body weight loss' appeared. The fasting blood glucose (FBG) was more than 7.8 mmol/L and (or) the random blood glucose (RBG) was more than 17.8 mmol/L. Both FBG and RBG became stable after 2 to 3 weeks. Levels of HbA1C in group B and D ([7.32±0.45]%, [9.41±0.45]%) were significantly higher than that of group A ([4.02±0.45]%) ( Pdiabetes vascular lesions.

  12. Orbital Models and Electronic Structure Theory

    DEFF Research Database (Denmark)

    Linderberg, Jan

    2012-01-01

    This tribute to the work by Carl Johan Ballhausen focuses on the emergence of quantitative means for the study of the electronic properties of complexes and molecules. Development, refinement and application of the orbital picture elucidated electric and magnetic features of ranges of molecules...

  13. Financing the Electronic Library: Models and Options.

    Science.gov (United States)

    Waters, Richard L.; Kralisz, Victor Frank

    1981-01-01

    Places the cost considerations associated with public library automation in a framework of public finance comfortable to most administrators, discusses the importance of experience with use patterns in the electronic library in opening up new and innovative financing methods, and stresses the role of the library in the information industry. (JL)

  14. Tumor induction and hair follicle damage for different electron penetrations in rat skin

    International Nuclear Information System (INIS)

    Burns, F.J.; Sinclair, I.P.; Albert, R.E.; Vanderlaan, M.

    1976-01-01

    The penetration and dose of an electron beam were varied in an attempt to locate the depth in growing-phase rat skin where irradiation was most effective in inducing tumors and morphological damage to the hair follicles. The hair was plucked to initiate the growing phase of the hair cycle, and 12 days later the dorsal skin was irradiated with electrons penetrating 0.5, 1.0, or 2.0 mm at doses from 500 to 4000 rad. Differences in the curves of tumor incidence as a function of dose for different penetrations were best resolved by plotting the results against the 0.4 mm dose, while comparable curves for destruction of the follicles were best resolved by the 0.8 mm dose. Since 0.8 mm corresponded approximately to the depth of the follicles, these results indicated that the target tissues for follicular damage and tumor induction were separated in depth and that the target for tumor induction was probably located in the region above or near the midpoint of the follicles. When the radiation penetrated sufficiently to reach the entire follicle, the number of tumors produced was not significantly greater than the number observed previously in resting-phase skin, and it was inferred that the additional size and greater mitotic activity of the growing-phase follicles at the time of irradiation did not increase the probability of tumor induction

  15. Preemptive analgesic effects of midazolam and diclofenac in rat model

    Directory of Open Access Journals (Sweden)

    Antigona Hasani

    2011-05-01

    Full Text Available The aim of the present study was to investigate the preemptive analgesic effects of intraperitoneally administrated midazolam and diclofenac, before acute and inflammatory induced pain in rat model.One hundred twenty-eight (n=8 in each group male Sprague Dawley rats were included in the study. Paw movements in response to thermal stimulation or paw flinching in response to formalin injection were compared after midazolam (0.1, 1, 5 and 10 mg/kg and diclofenac (10 mg/kg, intraperitoneal administration. Saline was used as a control.Preemptive analgesic effect was significant in both tests when diclofenac and midazolam was administrated before the pain stimuli (p<0.01 and p<0.001. Intraperitoneal injection of midazolam in doses 5 and 10 mg/kg, increase the response time in hot plate test and decrease the number of flinches in formalin test (p<0.01 vs. p<0.001. ED50 of midazolam (with diclofenac in hot plate test was 2.02 mg/kg (CI95% =-3.47-5.03 mg; and, 0.9 mg/kg (CI95% =-0.87-4.09 mg in phase I and 0.7 mg/kg (CI95% = 0.48-6.63 mg in phase II, in formalin test.Intraperitoneally administered midazolam and diclofenac had preemptive analgesic effects on acute thermal, and inflammatory induced pain in rats.

  16. Animal model of rapid crystalloid infusion in rats

    Directory of Open Access Journals (Sweden)

    Flavio Stillitano Orgaes

    2013-04-01

    Full Text Available PURPOSE: To describe an animal model of rapid intravenous infusion with different volumes of crystalloid and discuss the clinical findings. METHODS: Fifty six male Wistar rats were used, divided randomly in seven groups (n = 8. The rats of groups 1 to 6 received lactated Ringer´s solution intravenously, in the rate of 25 ml/min, with different volumes proportional to blood volume (BV. The rats of group 0 were submitted to the same procedure, but did not receive the fluid (control group. The data included respiratory rate, heart rate, saturation of peripheral oxygen (SpO2 in two times (before and after the infusion, and upshots (respiratory arrest and death. Dunnett´s test and ANOVA were used. RESULTS: The clinical signs significantly changed in the 2, 2.5 and 3 fold BV groups. The respiratory arrest was observed in the 1.5, 2, 2.5 and 3 fold BV groups, but death was present only in 2.5 and 3 fold BV groups. CONCLUSIONS: The infusion of crystalloid in the same volume of blood volume did not cause significant variation in respiratory and heart rate, saturation of peripheral oxygen and did not induce respiratory arrest. The infusion of a volume of 3 fold blood volume was lethal to all animals.

  17. On the applicability of one- and many-electron quantum chemistry models for hydrated electron clusters

    Science.gov (United States)

    Turi, László

    2016-04-01

    We evaluate the applicability of a hierarchy of quantum models in characterizing the binding energy of excess electrons to water clusters. In particular, we calculate the vertical detachment energy of an excess electron from water cluster anions with methods that include one-electron pseudopotential calculations, density functional theory (DFT) based calculations, and ab initio quantum chemistry using MP2 and eom-EA-CCSD levels of theory. The examined clusters range from the smallest cluster size (n = 2) up to nearly nanosize clusters with n = 1000 molecules. The examined cluster configurations are extracted from mixed quantum-classical molecular dynamics trajectories of cluster anions with n = 1000 water molecules using two different one-electron pseudopotenial models. We find that while MP2 calculations with large diffuse basis set provide a reasonable description for the hydrated electron system, DFT methods should be used with precaution and only after careful benchmarking. Strictly tested one-electron psudopotentials can still be considered as reasonable alternatives to DFT methods, especially in large systems. The results of quantum chemistry calculations performed on configurations, that represent possible excess electron binding motifs in the clusters, appear to be consistent with the results using a cavity structure preferring one-electron pseudopotential for the hydrated electron, while they are in sharp disagreement with the structural predictions of a non-cavity model.

  18. On the applicability of one- and many-electron quantum chemistry models for hydrated electron clusters

    Energy Technology Data Exchange (ETDEWEB)

    Turi, László, E-mail: turi@chem.elte.hu [Department of Physical Chemistry, Eötvös Loránd University, P.O. Box 32, H-1518 Budapest 112 (Hungary)

    2016-04-21

    We evaluate the applicability of a hierarchy of quantum models in characterizing the binding energy of excess electrons to water clusters. In particular, we calculate the vertical detachment energy of an excess electron from water cluster anions with methods that include one-electron pseudopotential calculations, density functional theory (DFT) based calculations, and ab initio quantum chemistry using MP2 and eom-EA-CCSD levels of theory. The examined clusters range from the smallest cluster size (n = 2) up to nearly nanosize clusters with n = 1000 molecules. The examined cluster configurations are extracted from mixed quantum-classical molecular dynamics trajectories of cluster anions with n = 1000 water molecules using two different one-electron pseudopotenial models. We find that while MP2 calculations with large diffuse basis set provide a reasonable description for the hydrated electron system, DFT methods should be used with precaution and only after careful benchmarking. Strictly tested one-electron psudopotentials can still be considered as reasonable alternatives to DFT methods, especially in large systems. The results of quantum chemistry calculations performed on configurations, that represent possible excess electron binding motifs in the clusters, appear to be consistent with the results using a cavity structure preferring one-electron pseudopotential for the hydrated electron, while they are in sharp disagreement with the structural predictions of a non-cavity model.

  19. Aortic superoxide production at the early hyperglycemic stage in a rat type 2 diabetes model and the effects of pravastatin.

    Science.gov (United States)

    Kikuchi, Chigusa; Kajikuri, Junko; Hori, Eisei; Nagami, Chie; Matsunaga, Tamihide; Kimura, Kazunori; Itoh, Takeo

    2014-01-01

    Endothelium-derived superoxide induces vascular dysfunctions. The aim of this study was to examine the activity of protein kinase C (PKC) isoforms and endothelial nitric oxide synthase (eNOS), which leads to vascular superoxide production in type 2 diabetes, in addition to the effects of pravastatin. We studied these mechanisms in Otsuka Long-Evans Tokushima Fatty (OLETF) rats (type 2 diabetes model) at the early hyperglycemic stage (vs. non-diabetic Long-Evans Tokushima Otsuka [LETO] rats). Superoxide production and catalase activity were measured in aortas, as were the protein expressions of PKCδ and phospho-Ser(1177) eNOS. Superoxide production was increased in OLETF rats, and this increase was inhibited by the selective conventional PKC (cPKC) inhibitor Gö6976 and by the non-selective cPKC and novel PKC inhibitor GF109203X. Phospho-Ser(1177) eNOS was significantly increased in OLETF rats, whereas the protein expressions of PKCδ and phosopho-Thr(505) PKCδ and catalase activity were all greatly reduced. Pravastatin administration to OLETF rats in vivo had normalizing effects on all of these variables. The increment in superoxide production seen in OLETF rats (but not the production in pravastatin-treated OLETF rats) was abolished by high concentration of N(ω)-nitro-L-arginine methyl ester (electron transport inhibitor of eNOS), by sepiapterin (precursor of tetrahydrobiopterin), and by LY294002 (phosphatidylinositol 3-kinase [PI3-kinase] inhibitor). In OLETF rats at the early hyperglycemic stage, aortic superoxide production is increased owing to activation of uncoupled eNOS through phosphorylation by PI3-kinase/Akt. This may be related to the observed reduction in PKCδ/catalase activities. Pravastatin inhibited endothelial superoxide production via normalization of PKCδ/catalase activities.

  20. Simple model of electron beam initiated dielectric breakdown

    International Nuclear Information System (INIS)

    Beers, B.L.; Daniell, R.E.; Delmer, T.N.

    1985-01-01

    A steady state model that describes the internal charge distribution of a planar dielectric sample exposed to a uniform electron beam was developed. The model includes the effects of charge deposition and ionization of the beam, separate trap-modulated mobilities for electrons and holes, electron-hole recombination, and pair production by drifting thermal electrons. If the incident beam current is greater than a certain critical value (which depends on sample thickness as well as other sample properties), the steady state solution is non-physical

  1. Comparison of two models of inflammatory bowel disease in rats.

    Science.gov (United States)

    Catana, Cristina Sorina; Magdas, Cristian; Tabaran, Flaviu Alexandru; Crăciun, Elena Cristina; Deak, Georgiana; Magdaş, Virginia Ana; Cozma, Vasile; Gherman, Călin Mircea; Berindan-Neagoe, Ioana; Dumitraşcu, Dan Lucian

    2018-03-26

    There is a need for experimental animal models for inflammatory bowel diseases (IBD), but no proposed model has been unanimously accepted. The aim of this study was to develop 2 affordable models of IBD in rats and to compare them. We produced IBD in rats using either dextran sodium sulfate (DSS) or 2, 4, 6-trinitrobenzene sulfonic acid (TNBS). The requirements for experimental models were: a predictable clinical course, histopathology and inflammation similar to human ulcerative colitis (UC) and Crohn's disease (CD). The effect of acute administration of DSS and TNBS on oxidative stress (as measured by the assessment of glutathione peroxidase - GPx) was verified. The activity of whole blood GPx was measured using a commercially available Randox kit (Crumlin, UK). The administration of DSS increased GPx activity compared to the control and TNBS-treated groups, but not to a statistically significant degree. Histological examination of the colonic mucosa following the administration of DSS showed multifocal erosions with minimal to mild inflammatory infiltrate, mainly by polymorphonuclear cells (PMN), lymphocytes and plasma cells. For TNBS-induced colitis, the histological changes manifested as multifocal areas of ulcerative colitis with mild to severe inflammatory infiltrate. Whole blood GPx values displayed a direct dependence on the chemical agent used. Our results show a correlation between histopathology, proinflammatory state and oxidative stress. The experimental DSSor TNBS-induced bowel inflammation used in this study corresponds to human IBD and is reproducible with characteristics indicative of acute inflammation in the case of the protocols mentioned.

  2. Localization of electrons by electron-electron interaction in an Anderson model

    International Nuclear Information System (INIS)

    Ritala, R.K.; Kurkijaervi, J.

    1981-01-01

    We study the effect of attractive Hubbard interaction on disordered electron system. We map the interacting system back to noninteracting one and determine self-consistently the disorder change due to interaction in the system. (author)

  3. Phenomenological model of an electron flow with a virtual cathode

    International Nuclear Information System (INIS)

    Koronovskij, A.A.; Khramov, A.E.; Anfinogenov, V.G.

    1999-01-01

    A phenomenological model of electron flow with a virtual cathode in diode space, which is a modification of cellular automation, is suggested. The type of models, called cellular conveyer, permits making allowance for distribution and delay in a beam with a virtual cathode. A good agreement between results of numerical study of electron flow dynamics and results obtained using the phenomenological model described has been achieved [ru

  4. Modelling of non-thermal electron cyclotron emission during ECRH

    International Nuclear Information System (INIS)

    Tribaldos, V.; Krivenski, V.

    1990-01-01

    The existence of suprathermal electrons during Electron Cyclotron Resonance Heating experiments in tokamaks is today a well established fact. At low densities the creation of large non-thermal electron tails affects the temperature profile measurements obtained by 2 nd harmonic, X-mode, low-field side, electron cyclotron emission. At higher densities suprathermal electrons can be detected by high-field side emission. In electron cyclotron current drive experiments a high energy suprathermal tail, asymmetric in v, is observed. Non-Maxwellian electron distribution functions are also typically observed during lower-hybrid current drive experiments. Fast electrons have been observed during ionic heating by neutral beams as well. Two distinct approaches are currently used in the interpretation of the experimental results: simple analytical models which reproduce some of the expected non-Maxwellian characteristics of the electron distribution function are employed to get a qualitative picture of the phenomena; sophisticated numerical Fokker-Planck calculations give the electron distribution function from which the emission spectra are computed. No algorithm is known to solve the inverse problem, i.e. to compute the electron distribution function from the emitted spectra. The proposed methods all relay on the basic assumption that the electron distribution function has a given functional dependence on a limited number of free parameters, which are then 'measured' by best fitting the experimental results. Here we discuss the legitimacy of this procedure. (author) 7 refs., 5 figs

  5. Dynamic pricing models for electronic business

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    learning. We present a detailed example of an e-business market to show the ... to auction based models and §6 is devoted to game theoretic models. ..... Machine learning models: An e-business market provides a rich playground for online.

  6. Electronic learning and constructivism: a model for nursing education.

    Science.gov (United States)

    Kala, Sasikarn; Isaramalai, Sang-Arun; Pohthong, Amnart

    2010-01-01

    Nurse educators are challenged to teach nursing students to become competent professionals, who have both in-depth knowledge and decision-making skills. The use of electronic learning methods has been found to facilitate the teaching-learning process in nursing education. Although learning theories are acknowledged as useful guides to design strategies and activities of learning, integration of these theories into technology-based courses appears limited. Constructivism is a theoretical paradigm that could prove to be effective in guiding the design of electronic learning experiences for the purpose of providing positive outcomes, such as the acquisition of knowledge and decision-making skills. Therefore, the purposes of this paper are to: describe electronic learning, present a brief overview of what is known about the outcomes of electronic learning, discuss constructivism theory, present a model for electronic learning using constructivism, and describe educators' roles emphasizing the utilization of the model in developing electronic learning experiences in nursing education.

  7. Power Electronic Packaging Design, Assembly Process, Reliability and Modeling

    CERN Document Server

    Liu, Yong

    2012-01-01

    Power Electronic Packaging presents an in-depth overview of power electronic packaging design, assembly,reliability and modeling. Since there is a drastic difference between IC fabrication and power electronic packaging, the book systematically introduces typical power electronic packaging design, assembly, reliability and failure analysis and material selection so readers can clearly understand each task's unique characteristics. Power electronic packaging is one of the fastest growing segments in the power electronic industry, due to the rapid growth of power integrated circuit (IC) fabrication, especially for applications like portable, consumer, home, computing and automotive electronics. This book also covers how advances in both semiconductor content and power advanced package design have helped cause advances in power device capability in recent years. The author extrapolates the most recent trends in the book's areas of focus to highlight where further improvement in materials and techniques can d...

  8. A Electronic Map Data Model Based on PDF

    Science.gov (United States)

    Zhou, Xiaodong; Yang, Chuncheng; Meng, Nina; Peng, Peng

    2018-05-01

    In this paper, we proposed the PDFEMAP (PDF electronic map) that is a kind of new electronic map products aiming at the current situation and demand of the use of electronic map products. Firstly gives the definition and characteristics of PDFEMAP, followed by a detailed description of the data model and method for generating PDFEMAP, and finally expounds application modes of the PDFEMAP which feasibility and effectiveness are verified.

  9. Transmission and scanning electron microscopy study of the characteristics and morphology of pericytes and novel desmin-immunopositive perivascular cells before and after castration in rat anterior pituitary gland.

    Science.gov (United States)

    Jindatip, Depicha; Fujiwara, Ken; Kouki, Tom; Yashiro, Takashi

    2012-09-01

    Pericytes are perivascular cells associated with microcirculation. Typically, they are localized close to the capillary wall, underneath the basement membrane, and have sparse cytoplasm and poorly developed cell organelles. However, the specific properties of pericytes vary by organ and the conditions within organs. We recently demonstrated that pericytes in rat anterior pituitary gland produce type I and III collagens. The present study attempted to determine the morphological characteristics of these pituitary pericytes. Castrated rats were used as a model of hormonal and vascular changes in the gland. Pericytes, as determined by desmin immunohistochemistry, were more numerous and stained more intensely in castrated rats. Transmission electron microscopy revealed that pituitary pericytes displayed the typical characteristics of pericytes. In pituitary sections from castrated rats, the Golgi apparatus of pericytes was well developed and the rough endoplasmic reticulum was elongated. Additionally, scanning electron microscopy revealed four pericyte shapes: oval, elongate, triangular, and multiangular. As compared with normal rats, the proportion of oval pericytes was lower, and the proportions of the other three shapes were higher, in castrated rats. These results suggest that pericytes change their fine structure and cell shape in response to hormonal and vascular changes in the anterior pituitary gland. In addition, a novel type of perivascular cell was found by desmin immunoelectron microscopy. The morphological properties of these cells were dissimilar to those of pericytes. The cells were localized in the perivascular space, had no basement membrane, and contained dilated rough endoplasmic reticulum. This new cell type will require further study of its origin and characteristics.

  10. Modeling postpartum depression in rats: theoretic and methodological issues

    Science.gov (United States)

    Ming, LI; Shinn-Yi, CHOU

    2016-01-01

    The postpartum period is when a host of changes occur at molecular, cellular, physiological and behavioral levels to prepare female humans for the challenge of maternity. Alteration or prevention of these normal adaptions is thought to contribute to disruptions of emotion regulation, motivation and cognitive abilities that underlie postpartum mental disorders, such as postpartum depression. Despite the high incidence of this disorder, and the detrimental consequences for both mother and child, its etiology and related neurobiological mechanisms remain poorly understood, partially due to the lack of appropriate animal models. In recent decades, there have been a number of attempts to model postpartum depression disorder in rats. In the present review, we first describe clinical symptoms of postpartum depression and discuss known risk factors, including both genetic and environmental factors. Thereafter, we discuss various rat models that have been developed to capture various aspects of this disorder and knowledge gained from such attempts. In doing so, we focus on the theories behind each attempt and the methods used to achieve their goals. Finally, we point out several understudied areas in this field and make suggestions for future directions. PMID:27469254

  11. Modeling postpartum depression in rats: theoretic and methodological issues

    Directory of Open Access Journals (Sweden)

    Ming LI

    2018-06-01

    Full Text Available The postpartum period is when a host of changes occur at molecular, cellular, physiological and behavioral levels to prepare female humans for the challenge of maternity. Alteration or prevention of these normal adaptions is thought to contribute to disruptions of emotion regulation, motivation and cognitive abilities that underlie postpartum mental disorders, such as postpartum depression. Despite the high incidence of this disorder, and the detrimental consequences for both mother and child, its etiology and related neurobiological mechanisms remain poorly understood, partially due to the lack of appropriate animal models. In recent decades, there have been a number of attempts to model postpartum depression disorder in rats. In the present review, we first describe clinical symptoms of postpartum depression and discuss known risk factors, including both genetic and environmental factors. Thereafter, we discuss various rat models that have been developed to capture various aspects of this disorder and knowledge gained from such attempts. In doing so, we focus on the theories behind each attempt and the methods used to achieve their goals. Finally, we point out several understudied areas in this field and make suggestions for future directions.

  12. Vascularized anal autotransplantation model in rats: preliminary report.

    Science.gov (United States)

    Araki, J; Mihara, M; Narushima, M; Iida, T; Sato, T; Koshima, I

    2011-11-01

    Ostomy has served as an effective surgery for various anorectal disfunctions. However, it must also be noted that those patients suffered greatly from stresses caused by their stoma. Many alternative therapies have been developed, but none have solved this critical issue. Meanwhile, due to the improvements in operative methods and immunosuppressive therapy, allotranplantation has gained great popularity in recent years. Therefore, we began development of an anal transplantation model. The operation was performed in six adult Wistar rats that were divided into two groups. Group 1 underwent vascular anastomoses, while group 2 did not Group 1 grafts survived, fully recovering anal function. However, many of the group 2 grafts did not survive; those that did survive showed major defects in their anus, never recovering anal function. We succeeded in establishing the rat anal transplantation model utilizing super-microsurgery. While research in anal transplantation was behind compared to that in other fields, we hope that this model will bring significant possibilities for the future. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Peculiarities of designing Holistic Electronic Government Services Integration Model

    Directory of Open Access Journals (Sweden)

    Tadas Limba

    2011-12-01

    Full Text Available Purpos– the aim ok this paper is to develop a Holistic Electronic Government Services Integration Model which could ensure the efficient integration of electronic government services in the local self-government level.Methodolog– the following analyses have been carried out in thirkpaper: theoretical-systematic; normative and conceptual comparative analysis of the researcha A method of modeling has also been applied.Finding– the scientific work analyzes the improvement opportunities of the models of electronic government services and their application alternatives in Lithuanian municipalities. The newly developed model of electronic government services that has been designed basng on the principle of integrating online expert consultation is primarily targeted at improvement of inside processes’ changes of an organization. Practicing the application of that model in the local self-government level starting with improvement of inside processes of an organization should help adapt more accurately and efficiently to the changing needs of the society while providing electronic government services, thus establishing a higher public value.Practical implication– the practical novelty of work is reflected not only through the integration opportunities’ assessment of the principle of online expert consultation services into the theoretical models of electronic government services that have already been developed by the scientists, but also on the basis of this principle there has been created a “Holistic Electronic Government Services Integration Model” in accordance with “E-Diamond” model basis and its practical application realization with the design of “The project of implementing the principle of online expert consultation on the model of electronic government services” for the future investigations.Originalit– the systematic, comparative analysis of the models of electronic government services carried out in the scientific

  14. Simulation model for electron irradiated IGZO thin film transistors

    Science.gov (United States)

    Dayananda, G. K.; Shantharama Rai, C.; Jayarama, A.; Kim, Hyun Jae

    2018-02-01

    An efficient drain current simulation model for the electron irradiation effect on the electrical parameters of amorphous In-Ga-Zn-O (IGZO) thin-film transistors is developed. The model is developed based on the specifications such as gate capacitance, channel length, channel width, flat band voltage etc. Electrical parameters of un-irradiated IGZO samples were simulated and compared with the experimental parameters and 1 kGy electron irradiated parameters. The effect of electron irradiation on the IGZO sample was analysed by developing a mathematical model.

  15. Modeling the distribution of Norway rats (Rattus norvegicus on offshore islands in the Falkland Islands

    Directory of Open Access Journals (Sweden)

    Michael A. Tabak

    2015-01-01

    Full Text Available Non-native rats (Rattus spp. threaten native island species worldwide. Efforts to eradicate them from islands have increased in frequency and become more ambitious in recent years. However, the long-term success of some eradication efforts has been compromised by the ability of rats, particularly Norway rats (Rattus norvegicus which are good swimmers, to recolonize islands following eradications. In the Falkland Islands, an archipelago in the South Atlantic Ocean, the distance of 250 m between islands (once suggested as the minimum separation distance for an effective barrier to recolonization has shown to be insufficient. Norway rats are present on about half of the 503 islands in the Falklands. Bird diversity is lower on islands with rats and two vulnerable passerine species, Troglodytes cobbi (the only endemic Falkland Islands passerine and Cinclodes antarcticus, have greatly reduced abundances and/or are absent on islands with rats. We used logistic regression models to investigate the potential factors that may determine the presence of Norway rats on 158 islands in the Falkland Islands. Our models included island area, distance to the nearest rat-infested island, island location, and the history of island use by humans as driving variables. Models best supported by data included only distance to the nearest potential source of rats and island area, but the relative magnitude of the effect of distance and area on the presence of rats varied depending on whether islands were in the eastern or western sector of the archipelago. The human use of an island was not a significant parameter in any models. A very large fraction (72% of islands within 500 m of the nearest potential rat source had rats, but 97% of islands farther than 1,000 m away from potential rat sources were free of rats.

  16. Unified model of secondary electron cascades in diamond

    International Nuclear Information System (INIS)

    Ziaja, Beata; London, Richard A.; Hajdu, Janos

    2005-01-01

    In this article we present a detailed and unified theoretical treatment of secondary electron cascades that follow the absorption of x-ray photons. A Monte Carlo model has been constructed that treats in detail the evolution of electron cascades induced by photoelectrons and by Auger electrons following inner shell ionizations. Detailed calculations are presented for cascades initiated by electron energies between 0.1 and 10 keV. The present article expands our earlier work [B. Ziaja, D. van der Spoel, A. Szoeke, and J. Hajdu, Phys. Rev. B 64, 214104 (2001), Phys. Rev. B 66, 024116 (2002)] by extending the primary energy range, by improving the treatment of secondary electrons, especially at low electron energies, by including ionization by holes, and by taking into account their coupling to the crystal lattice. The calculations describe the three-dimensional evolution of the electron cloud, and monitor the equivalent instantaneous temperature of the free electron gas as the system cools. The dissipation of the impact energy proceeds predominantly through the production of secondary electrons whose energies are comparable to the binding energies of the valence (40-50 eV) and of the core electrons (300 eV). The electron cloud generated by a 10 keV electron is strongly anisotropic in the early phases of the cascade (t≤1 fs). At later times, the sample is dominated by low energy electrons, and these are scattered more isotropically by atoms in the sample. Our results for the total number of secondary electrons agree with available experimental data, and show that the emission of secondary electrons approaches saturation within about 100 fs following the primary impact

  17. Chronic intermittent hypoxia induces cardiac inflammation and dysfunction in a rat obstructive sleep apnea model.

    Science.gov (United States)

    Wei, Qin; Bian, Yeping; Yu, Fuchao; Zhang, Qiang; Zhang, Guanghao; Li, Yang; Song, Songsong; Ren, Xiaomei; Tong, Jiayi

    2016-11-01

    Chronic intermittent hypoxia is considered to play an important role in cardiovascular pathogenesis during the development of obstructive sleep apnea (OSA). We used a well-described OSA rat model induced with simultaneous intermittent hypoxia. Male Sprague Dawley rats were individually placed into plexiglass chambers with air pressure and components were electronically controlled. The rats were exposed to intermittent hypoxia 8 hours daily for 5 weeks. The changes of cardiac structure and function were examined by ultrasound. The cardiac pathology, apoptosis, and fibrosis were analyzed by H&E staining, TUNNEL assay, and picosirius staining, respectively. The expression of inflammation and fibrosis marker genes was analyzed by quantitative real-time PCR and Western blot. Chronic intermittent hypoxia/low pressure resulted in significant increase of left ventricular internal diameters (LVIDs), end-systolic volume (ESV), end-diastolic volume (EDV), and blood lactate level and marked reduction in ejection fraction and fractional shortening. Chronic intermittent hypoxia increased TUNNEL-positive myocytes, disrupted normal arrangement of cardiac fibers, and increased Sirius stained collagen fibers. The expression levels of hypoxia induced factor (HIF)-1α, NF-kB, IL-6, and matrix metallopeptidase 2 (MMP-2) were significantly increased in the heart of rats exposed to chronic intermittent hypoxia. In conclusion, the left ventricular function was adversely affected by chronic intermittent hypoxia, which is associated with increased expression of HIF-1α and NF-kB signaling molecules and development of cardiac inflammation, apoptosis and fibrosis. © 2016 by the Journal of Biomedical Research. All rights reserved.

  18. A novel model for NSAID induced gastroenteropathy in rats.

    Science.gov (United States)

    Singh, Devendra Pratap; Borse, Swapnil P; Nivsarkar, Manish

    2016-01-01

    Progress in management of Nonsteroidal anti-inflammatory drug (NSAID) induced gastrointestinal toxicity requires the availability of appropriate experimental animal models that are as close to humans as feasible. Our objective was to develop a rat model for NSAID-induced gastroenteropathy and also to simulate the common clinical scenario of co-administration of NSAID and proton pump inhibitor (PPI) to explore if PPI contribute to exacerbation of NSAID-enteropathy. Rats were treated twice daily with pantoprazole sodium (PTZ; 10mg/kg peroral) or vehicle for a total of 10days. In some experiments, Diclofenac sodium (DCF; 9mg/kg) or vehicle was administered orally twice daily for the final 5days of PTZ/vehicle administration. After the last dose on 9th day, rats in all the groups were fasted but water was provided ad libitum. 12h after the last dose on 10th day, rats in all the groups were euthanized and their gastrointestinal tracts were assessed for haemorrhagic lesions, lipid peroxidation, intestinal permeability and gastrointestinal luminal pH alterations. Changes in haemoglobin, haematocrit and serum levels of albumin, total protein, ALT and bilirubin were calculated. The macroscopic and histological evidence suggested that administration of DCF resulted in significant gastroenteropathic damage and co-administration of PTZ resulted in significant exacerbation of NSAID enteropathy, while attenuation of NSAID induced gastropathy was observed. Our results were further supported by the significant decrease in haemoglobin and haematocrit levels and serum levels of albumin and total proteins, an increase in oxidative stress and intestinal permeability with the use of DCF either alone or in combination with PTZ. This model was developed to simulate the human clinical situation during NSAID therapy and indeed the present DCF regimen caused both gastric and small bowel alterations, such as multiple erosive lesions, together with a decrease in haemoglobin, haematocrit

  19. A SIMPLE EXPERIMENTAL MODEL OF HEAT SHOCK RESPONSE IN RATS

    Directory of Open Access Journals (Sweden)

    Tufi Neder Meyer

    1998-10-01

    Full Text Available Objective: To obtain a simple model for the elicitation of the heat shock response in rats. Design: Laboratory study. Setting: University research laboratories. Sample: Seventy-nine adult male albino rats (weight range 200 g to 570 g. Procedures: Exposure to heat stress by heating animals in a warm bath for 5 min after their rectal temperatures reached 107.60 F (420 C. Liver and lung samples were collected for heat-shock protein 70 (HSP70 detection (Western analysis. Results: Western analysis was positive for HSP70 in the liver and in the lungs of heated animals. There was a temporal correlation between heating and HSP70 detection: it was strongest 1 day after heating and reduced afterwards. No heated animals died. Conclusion: These data show that heating rats in a warm (45o C bath, according to parameters set in this model, elicits efficiently the heat shock response.OBJETIVO: Obter um modelo simples para tentar esclarecer a resposta ao choque térmico em ratos. LOCAL: Laboratório de pesquisa da Universidade. MÉTODO: Amostra: 79 ratos albinos, adultos, entre 200g a 570g. Procedimentos: Exposição ao calor, em banho quente, por 5 minutos, após a temperatura retal chegar a 42 graus centigrados. Biópsias de fígado e pulmão foram obtidas para detectar a proteina 70 (HSP 70, pelo "Western blot". RESULTADOS: As análises foram positivas nos animais aquecidos, com uma correlação entre aquecimento e constatação da HSP 70. Foi mais elevada no primeiro dia e não houve óbitos nos animais aquecidos. CONCLUSÃO: Os ratos aquecidos a 45 graus centígrados respondem eficientemente ao choque térmico.

  20. Microsurgical Bypass Training Rat Model: Part 2-Anastomosis Configurations.

    Science.gov (United States)

    Tayebi Meybodi, Ali; Lawton, Michael T; Yousef, Sonia; Mokhtari, Pooneh; Gandhi, Sirin; Benet, Arnau

    2017-11-01

    Mastery of microsurgical anastomosis is key to achieving good outcomes in cerebrovascular bypass procedures. Animal models (especially rodents) provide an optimal preclinical bypass training platform. However, the existing models for practicing different anastomosis configurations have several limitations. We sought to optimize the use of the rat's abdominal aorta and common iliac arteries (CIA) for practicing the 3 main anastomosis configurations commonly used in cerebrovascular surgery. Thirteen male Sprague-Dawley rats underwent inhalant anesthesia. The abdominal aorta and the CIAs were exposed. The distances between the major branches of the aorta were measured to find the optimal location for an end-to-end anastomosis. Also, the feasibility of performing side-to-side and end-to-side anastomoses between the CIAs was assessed. All bypass configurations could be performed between the left renal artery and the CIA bifurcation. The longest segments of the aorta without major branches were 1) between the left renal and left iliolumbar arteries (16.9 mm ± 4.6), and 2) between the right iliolumbar artery and the aortic bifurcation (9.7 mm ± 4.7). The CIAs could be juxtaposed for an average length of 7.6 mm ± 1.3, for a side-to-side anastomosis. The left CIA could be successfully reimplanted on to the right CIA at an average distance of 9.1 mm ± 1.6 from the aortic bifurcation. Our results show that rat's abdominal aorta and CIAs may be effectively used for all the anastomosis configurations used in cerebral revascularization procedures. We also provide technical nuances and anatomic descriptions to plan for practicing each bypass configuration. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Teaching Behavioral Modeling and Simulation Techniques for Power Electronics Courses

    Science.gov (United States)

    Abramovitz, A.

    2011-01-01

    This paper suggests a pedagogical approach to teaching the subject of behavioral modeling of switch-mode power electronics systems through simulation by general-purpose electronic circuit simulators. The methodology is oriented toward electrical engineering (EE) students at the undergraduate level, enrolled in courses such as "Power…

  2. Problem Resolution through Electronic Mail: A Five-Step Model.

    Science.gov (United States)

    Grandgenett, Neal; Grandgenett, Don

    2001-01-01

    Discusses the use of electronic mail within the general resolution and management of administrative problems and emphasizes the need for careful attention to problem definition and clarity of language. Presents a research-based five-step model for the effective use of electronic mail based on experiences at the University of Nebraska at Omaha.…

  3. The physiological response of obese rat model with rambutan peel extract treatment

    Directory of Open Access Journals (Sweden)

    Sri Rahayu Lestari

    2014-09-01

    Full Text Available Objective: To determine body weight gain, expression of Igf-1 and Igf-1 receptor on obese rat model treated with rambutan peel extract (RPE as a physiological response. Methods: Normal and obese rat feed with normal and high calorie diet around 1 2 weeks and continued to treat with ellagic acid, RPE 15, 30 and 60 mg/kg body weight respectively. Physiological responses observed were weight gain and expression of Igf-1 with its receptor. Body weight of rat was weighed once per week. Expression of Igf-1 and igf-1R observed with fluorescence immunohistochemistry. The intensity of Igf-1 and Igf-1R expression was analysis using FSX-BSW software. Results: The lowest weight gain was obtained on obese rat model treated with RPE 30 mg/kg body weight. The expression of Igf-1 and Igf-1R were reduced on obese rat model treated with RPE compared with obese rat model of non treatment (P<0.05. The low expression of Igf-1 and Igf-1R was found on obese rat model treated with ellagic acid and RPE 30 mg/kg body weight. Conclusions: The RPE was effecting to the physiological response on obese rat model. The RPE 30 mg/kg body weight inhibited body weight gain and decreased the expression of Igf-1 and Igf- 1R of obese rat model.

  4. Electronic field emission models beyond the Fowler-Nordheim one

    Science.gov (United States)

    Lepetit, Bruno

    2017-12-01

    We propose several quantum mechanical models to describe electronic field emission from first principles. These models allow us to correlate quantitatively the electronic emission current with the electrode surface details at the atomic scale. They all rely on electronic potential energy surfaces obtained from three dimensional density functional theory calculations. They differ by the various quantum mechanical methods (exact or perturbative, time dependent or time independent), which are used to describe tunneling through the electronic potential energy barrier. Comparison of these models between them and with the standard Fowler-Nordheim one in the context of one dimensional tunneling allows us to assess the impact on the accuracy of the computed current of the approximations made in each model. Among these methods, the time dependent perturbative one provides a well-balanced trade-off between accuracy and computational cost.

  5. Application of the Technology Acceptance Model (TAM) in electronic ...

    African Journals Online (AJOL)

    Application of the Technology Acceptance Model (TAM) in electronic ticket purchase for ... current study examined the perceived usefulness and ease of use of online technology ... The findings are discussed in the light of these perspectives.

  6. Modelling and implementing electronic health records in Denmark

    DEFF Research Database (Denmark)

    Bernstein, Knut; Rasmussen, Morten Bruun; Vingtoft, Søren

    2003-01-01

    The Danish Health IT strategy points out that integration between electronic health records (EHR) systems has a high priority. This paper reporst reports new tendencies in modelling and integration platforms globally and how this is reflected in the natinal development....

  7. A rat model of concurrent combined injuries (polytrauma)

    Science.gov (United States)

    Akscyn, Robert M; Franklin, J Lee; Gavrikova, Tatyana A; Schwacha, Martin G; Messina, Joseph L

    2015-01-01

    Polytrauma, a combination of injuries to more than one body part or organ system, is common in modern warfare and in automobile and industrial accidents. The combination of injuries can include burn injury, fracture, hemorrhage, trauma to the extremities, and trauma to specific organ systems. To investigate the effects of combined injuries, we have developed a new and highly reproducible model of polytrauma. This model combines burn injury with soft tissue and gastrointestinal (GI) tract trauma. Male Sprague Dawley rats were subjected to a 15-20% total body surface area scald burn, or a single puncture of the cecum with a G30 needle, or the combination of both injuries (polytrauma). Unlike many ‘double hit’ models, the injuries in our model were performed simultaneously. We asked whether multiple minor injuries, when combined, would result in a distinct phenotype, different from single minor injuries or a more severe single injury. There were differences between the single injuries and polytrauma in the maintenance of blood glucose, body temperature, body weight, hepatic mRNA and circulating levels of TNF-α, IL-1β and IL-6, and hepatic ER-stress. It has been suggested that models utilizing combinatorial injuries may be needed to more accurately model the human condition. We believe our model is ideal for studying the complex sequelae of polytrauma, which differs from single injuries. Insights gained from this model may suggest better treatment options to improve patient outcomes. PMID:26884923

  8. Electron microscopic observation of 137Cs-irradiated rat testis. Production of basal laminae for germ cells, despite their absence

    International Nuclear Information System (INIS)

    Sawada, Hajime; Esaki, Michiyo

    2003-01-01

    Whole body γ-ray irradiation of rats with caesium-137 ( 137 Cs) at embryonic day 20 induced marked reduction of the weight of the testis. Body weight and other tissues, however, seemed to remain normal. By light microscopy, complete loss of germ cells was observed in the testis. Other components, such as Sertoli cells and interstitial cells, seemed to be normal. The testes from day 8 postpartum rats contained very few spermatogonia compared with newborn rats, indicating loss of germ cells between days 0 and 8. In the adult, 137 Cs-irradiated testes showed two conspicuous features other than the loss of germ cells: empty vacuolar spaces between Sertoli cells and multilayered seminiferous tubule basal laminae (lamina densa). The junctional structures (ectoplasmic specializations) between Sertoli cells, however, seemed normal. The thickness of each layer of multilayered basal laminae was the same as that of normal rats and electron-lucent layers similar to lamina lucida were interposed between them. Of the empty vacuolar spaces between Sertoli cells, basal laminae bridge the gap. The basal laminae contained laminin, type IV collagen and heparan sulphate proteoglycan evenly distributed among layers, suggesting a normal composition. Rough estimation of the amount of basal laminae deposited in 137 Cs-irradiated rats indicates that it is within a range similar to that in normal testis. These features imply that Sertoli cells are, in part, determined perinatally to produce basal laminae for germ-line cells. (author)

  9. Uptake and processing of [3H]retinoids in rat liver studied by electron microscopic autoradiography

    International Nuclear Information System (INIS)

    Hendriks, H.F.; Elhanany, E.; Brouwer, A.; de Leeuw, A.M.; Knook, D.L.

    1988-01-01

    The role of rat liver cell organelles in retinoid uptake and processing was studied by electron microscopic autoradiography. [ 3 H]Retinoids were administered either orally, to make an inventory of the cell organelles involved, or intravenously as chylomicron remnant constituents to study retinoid processing by the liver with time. No qualitative differences were observed between the two routes of administration. Time-related changes in the distribution of grains were studied using chylomicron remnant [ 3 H]retinoids. The percentages of grains observed over cells and the space of Disse at 5 and 30 min after administration were, respectively: parenchymal cells, 72.6 and 70.4%; fat-storing cells, 5.0 and 18.1%, and the space of Disse, 14.4 and 8.9%. Low numbers of grains were observed over endothelial and Kupffer cells. The percentages of grains observed over parenchymal cell organelles were, respectively: sinusoidal area, 59.6 and 34.4%; smooth endoplasmic reticulum associated with glycogen, 13.8 and 13.4%; mitochondria, 5.4 and 13.6%; rough endoplasmic reticulum, 4.2 and 7.3%, and rough endoplasmic reticulum associated with mitochondria, 3.7 and 6.5%. It is concluded that chylomicron remnant [ 3 H]retinoids in combination with electron microscopic autoradiography provide a good system to study the liver processing of retinoids in vivo. These results, obtained in the intact liver under physiological conditions, further substantiate that retinoids are processed through parenchymal cells before storage occurs in fat-storing cell lipid droplets, that retinoid uptake is not mediated through lysosomes and that the endoplasmic reticulum is a major organelle in retinoid processing

  10. Radiation injuries of the spinal marrow of rats after irradiation with fast electrons

    International Nuclear Information System (INIS)

    Bruce-Micah, B.

    1973-01-01

    Twenty rats were fractionated irradiated on five days of the week with fast electrons of 42 MeV energy with a single dose of 200 r/day. After 1,000 r, 2,000 r, 3,000 r and 4,000 r HD, the animals were supravitally fixed and the spinal marrow was removed. The histological investigation already showed after 1,000 r HD distinct changes of the nerve cells and nerve fibers whereas the vessels appeared not to be injured. After 2,000 r HD, vessel changes with edemas occured for the first time. After 3,000 r HD, all nerve cells were severely injured, the glia tissue was denser and the vessels were enlarged despite endothelial proliferations. Furthermore, there were big edemas around the vessels and a beginning of demyelinisation in the dorsal column. After 4,000 r HD, a great part of the nerve cells and also a few glia cells were destroyed. The remaining glia cells were pyknotic and had partly several nucleoli. The tractus of the white matter consisted almost only now of a glia felt. With a survival time of six weeks, the glia had greatly regenerated and numerous new capillaries had sprouted in the grey matter. The white matter was strongly demyelinised. In the front lateral column, small round necrosis centres were visible. 18 weeks after irradiation, the glia tissue had greatly rebuilt itself. There were only very few nerve cells present. The strong sprouting of new capillaries in the grey matter was most noticeable. The results show that the application of fast electrons is of no advantage as regards injuring the nerve tissue compared to X-rays. (orig./LH) [de

  11. Supercomplexes of the mitochondrial electron transport chain decline in the aging rat heart.

    Science.gov (United States)

    Gómez, Luis A; Monette, Jeffrey S; Chavez, Juan D; Maier, Claudia S; Hagen, Tory M

    2009-10-01

    Accumulation of mitochondrial electron transport chain (ETC) defects is a recognized hallmark of the age-associated decline in cardiac bioenergetics; however, the molecular events involved are only poorly understood. In the present work, we hypothesized that age-related ETC deterioration stemmed partly from disassociation of large solid-state macromolecular assemblies termed "supercomplexes". Mitochondrial proteins from young and old rat hearts were separated by blue native-PAGE, protein bands analyzed by LC-MALDI-MS/MS, and protein levels quantified by densitometry. Results showed that supercomplexes comprised of various stoichiometries of complexes I, III and IV were observed, and declined significantly (p<0.05, n=4) with age. Supercomplexes displaying the highest molecular masses were the most severely affected. Considering that certain diseases (e.g. Barth Syndrome) display similar supercomplex destabilization as our results for aging, the deterioration in ETC supercomplexes may be an important underlying factor for both impaired mitochondrial function and loss of cardiac bioenergetics with age.

  12. A blueberry-enriched diet attenuates nephropathy in a rat model of hypertension via reduction in oxidative stress.

    Directory of Open Access Journals (Sweden)

    Carrie M Elks

    Full Text Available To assess renoprotective effects of a blueberry-enriched diet in a rat model of hypertension. Oxidative stress (OS appears to be involved in the development of hypertension and related renal injury. Pharmacological antioxidants can attenuate hypertension and hypertension-induced renal injury; however, attention has shifted recently to the therapeutic potential of natural products as antioxidants. Blueberries (BB have among the highest antioxidant capacities of fruits and vegetables.Male spontaneously hypertensive rats received a BB-enriched diet (2% w/w or an isocaloric control diet for 6 or 12 weeks or 2 days. Compared to controls, rats fed BB-enriched diet for 6 or 12 weeks exhibited lower blood pressure, improved glomerular filtration rate, and decreased renovascular resistance. As measured by electron paramagnetic resonance spectroscopy, significant decreases in total reactive oxygen species (ROS, peroxynitrite, and superoxide production rates were observed in kidney tissues in rats on long-term dietary treatment, consistent with reduced pathology and improved function. Additionally, measures of antioxidant status improved; specifically, renal glutathione and catalase activities increased markedly. Contrasted to these observations indicating reduced OS in the BB group after long-term feeding, similar measurements made in rats fed the same diet for only 2 days yielded evidence of increased OS; specifically, significant increases in total ROS, peroxynitrite, and superoxide production rates in all tissues (kidney, brain, and liver assayed in BB-fed rats. These results were evidence of "hormesis" during brief exposure, which dissipated with time as indicated by enhanced levels of catalase in heart and liver of BB group.Long-term feeding of BB-enriched diet lowered blood pressure, preserved renal hemodynamics, and improved redox status in kidneys of hypertensive rats and concomitantly demonstrated the potential to delay or attenuate development

  13. Model potentials in liquid water ionization by fast electron impact

    International Nuclear Information System (INIS)

    De Sanctis, M L; Stia, C R; Fojón, O A; Politis, M-F; Vuilleumier, R

    2015-01-01

    We study the ionization of water molecules in liquid phase by fast electron impact. We use our previous first-order model within an independent electron approximation that allows the reduction of the multielectronic problem into a monoelectronic one. The initial molecular states of the liquid water are represented in a realistic way through a Wannier orbital formalism. We complete our previous study by taking into account approximately the influence of the passive electrons of the target by means of different model potentials. We compute multiple differential cross sections for the most external orbital 1B 1 and compare them with other results

  14. Thermal modeling and design of electronic systems and devices

    International Nuclear Information System (INIS)

    Wirtz, R.A.; Lehmann, G.L.

    1990-01-01

    The thermal control electronic devices, particularly those in complex systems with high heat flux density, continues to be of interest to engineers involved in system cooling design and analysis. This volume contains papers presented at the 1990 ASME Winter Annual Meeting in two K-16 sponsored sessions: Empirical Modeling of Heat Transfer in Complex Electronic Systems and Design and Modeling of Heat Transfer Devices in High-Density Electronics. The first group deals with understanding the heat transfer processes in these complex systems. The second group focuses on the use of analysis techniques and empirically determined data in predicting device and system operating performance

  15. Aspergillus infection monitored by multimodal imaging in a rat model.

    Science.gov (United States)

    Pluhacek, Tomas; Petrik, Milos; Luptakova, Dominika; Benada, Oldrich; Palyzova, Andrea; Lemr, Karel; Havlicek, Vladimir

    2016-06-01

    Although myriads of experimental approaches have been published in the field of fungal infection diagnostics, interestingly, in 21st century there is no satisfactory early noninvasive tool for Aspergillus diagnostics with good sensitivity and specificity. In this work, we for the first time described the fungal burden in rat lungs by multimodal imaging approach. The Aspergillus infection was monitored by positron emission tomography and light microscopy employing modified Grocott's methenamine silver staining and eosin counterstaining. Laser ablation inductively coupled plasma mass spectrometry imaging has revealed a dramatic iron increase in fungi-affected areas, which can be presumably attributed to microbial siderophores. Quantitative elemental data were inferred from matrix-matched standards prepared from rat lungs. The iron, silver, and gold MS images collected with variable laser foci revealed that particularly silver or gold can be used as excellent elements useful for sensitively tracking the Aspergillus infection. The limit of detection was determined for both (107) Ag and (197) Au as 0.03 μg/g (5 μm laser focus). The selective incorporation of (107) Ag and (197) Au into fungal cell bodies and low background noise from both elements were confirmed by energy dispersive X-ray scattering utilizing the submicron lateral resolving power of scanning electron microscopy. The low limits of detection and quantitation of both gold and silver make ICP-MS imaging monitoring a viable alternative to standard optical evaluation used in current clinical settings. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Physiologically-Based Pharmacokinetic (PBPK) Model for the Thyroid Hormones in the Pregnant Rat and Fetus.

    Science.gov (United States)

    A developmental PBPK model is constructed to quantitatively describe the tissue economy of the thyroid hormones (THs), thyroxine (T4) and triiodothyronine (T3), in the rat. The model is also used to link maternal (THs) to rat fetal tissues via placental transfer. THs are importan...

  17. Validation of infrared thermography in serotonin-induced itch model in rats

    DEFF Research Database (Denmark)

    Dagnæs-Hansen, Frederik; Jasemian, Yousef; Gazerani, Parisa

    The number of scratching bouts is generally used as a standard method in animal models of itch. The aim of the present study was to validate the application of infrared thermography (IR-Th) in a serotonin-induced itch model in rats. Adult Sprague-Dawley male rats (n = 24) were used in 3 consecuti...

  18. Spreadsheet Modeling of Electron Distributions in Solids

    Science.gov (United States)

    Glassy, Wingfield V.

    2006-01-01

    A series of spreadsheet modeling exercises constructed as part of a new upper-level elective course on solid state materials and surface chemistry is described. The spreadsheet exercises are developed to provide students with the opportunity to interact with the conceptual framework where the role of the density of states and the Fermi-Dirac…

  19. Evaluation of treatment for dry eye with 2-hydroxyestradiol using a dry eye rat model.

    Science.gov (United States)

    Higuchi, Akihiro; Oonishi, Erina; Kawakita, Tetsuya; Tsubota, Kazuo

    2016-01-01

    2-hydroxy estradiol (2-OHE2) is a catechol derivative of 17β -Estradiol (E2) and it is synthesized from E2 catalyzed by cytochrome P4501A1. Previous studies reported that 2-OHE2 is a physiologic antioxidant in lipoproteins, liver microsomes, and the brain. Catechol derivatives show an anti-inflammatory effect through the inhibition of prostaglandin endoperoxide synthase (PGS) activity. Corneal erosion caused by dry eye is related to an increase in oxidative stress and inflammation in ocular surface cells. We investigated the therapeutic effects of 2-OHE2 on corneal damage caused by dry eye. Steroidal radical scavenging activity was confirmed through the electron spin resonance (ESR) method. PGS activity was measured using the COX Fluorescent Activity Assay Kit. To evaluate the effect of 2-OHE2 on the treatment for dry eye, 2-OHE2 was applied as an eye drop experiment using dry eye model rats. 2-OHE2 scavenged tyrosyl radical and possibly suppressed oxidative stress in corneal epithelial cells. In addition, 2-OHE2 inhibited PGS activity, and 2-OHE2 is probably a competitive inhibitor of PGS. Corneal PGS activity was upregulated in the dry eye group. Therefore, 2-OHE2 eye drops improved corneal erosion in dry eye model rats. 2-OHE2 is a candidate for the treatment of dry eye through the suppression of inflammation and oxidative stress in the cornea.

  20. Tiaolipiwei Acupuncture Reduces Albuminuria by Alleviating Podocyte Lesions in a Rat Model of Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Zhilong Zhang

    2018-01-01

    Full Text Available Background. Diabetic nephropathy is a common and serious complication of diabetes and a major cause of end-stage renal disease. Tiaolipiwei acupuncture is a safe treatment approach that may be effective for lowering albuminuria in diabetic nephropathy. Yet, the exact mechanisms of this therapeutic effect are unclear. Methods. A rodent model of type 2 diabetic nephropathy (T2DN was induced by a high-fat diet combined with low-dose streptozotocin. T2DN rats were treated with Tiaolipiwei acupuncture (ACU for 4, 8, or 12 weeks. At the end of treatment, urinary and blood samples were collected for analysis. Transmission electron microscopy was used to observe morphological changes, and protein expression levels of nephrin, CD2AP, podocalyxin, and desmin were quantified in renal tissue. Results. Compared to the T2DN groups, the T2DN + ACU groups showed significant improvements in 24-hour urinary protein, serum urea, cholesterol, and triglycerides at all time points. ACU treatment also improved the density of slit diaphragms. Simultaneously, ACU promoted the renal expression of nephrin, CD2AP, and podocalyxin and decreased the expression of desmin. Conclusion. Our study suggests that Tiaolipiwei acupuncture ameliorates podocyte lesions to reduce albuminuria and prevent the progression of T2DN in a rat model.

  1. Developing a model for application of electronic banking based on electronic trust

    Directory of Open Access Journals (Sweden)

    Amir Hooshang Nazarpoori

    2014-05-01

    Full Text Available This study develops a model for application of electronic banking based on electronic trust among costumers of Day bank in KhoramAbad city. A sample of 150 people was selected based on stratified random sampling. Questionnaires were used for the investigation. Results indicate that technology-based factors, user-based factors, and trust had negative relationships with perceived risk types including financial, functional, personal, and private. Moreover, trust including trust in system and trust in bank had a positive relationship with tendency to use and real application of electronic banking.

  2. Accounting of inter-electron correlations in the model of mobile electron shells

    International Nuclear Information System (INIS)

    Panov, Yu.D.; Moskvin, A.S.

    2000-01-01

    One studied the basic peculiar features of the model for mobile electron shells for multielectron atom or cluster. One offered a variation technique to take account of the electron correlations where the coordinates of the centre of single-particle atomic orbital served as variation parameters. It enables to interpret dramatically variation of electron density distribution under anisotropic external effect in terms of the limited initial basis. One studied specific correlated states that might make correlation contribution into the orbital current. Paper presents generalization of the typical MO-LCAO pattern with the limited set of single particle functions enabling to take account of additional multipole-multipole interactions in the cluster [ru

  3. Establishment of a rat model of early-stage liver failure and Th17/Treg imbalance

    OpenAIRE

    LI Dong; LU Zhonghua; GAN Jianhe

    2016-01-01

    ObjectiveTo investigate the methods for establishing a rat model of early-stage liver failure and the changes in Th17, Treg, and Th17/Treg after dexamethasone and thymosin interventions. MethodsA total of 64 rats were randomly divided into carbon tetrachloride (CCl4) group and endotoxin [lipopolysaccharide (LPS)]/D-galactosamine (D-GalN) combination group to establish the rat model of early-stage liver failure. The activities of the rats and changes in liver function and whole blood Th17 and ...

  4. A Model for an Electronic Information Marketplace

    Directory of Open Access Journals (Sweden)

    Wei Ge

    2005-11-01

    Full Text Available As the information content on the Internet increases, the task of locating desired information and assessing its quality becomes increasingly difficult. This development causes users to be more willing to pay for information that is focused on specific issues, verifiable, and available upon request. Thus, the nature of the Internet opens up the opportunity for information trading. In this context, the Internet cannot only be used to close the transaction, but also to deliver the product - desired information - to the user. Early attempts to implement such business models have fallen short of expectations. In this paper, we discuss the limitations of such practices and present a modified business model for information trading, which uses a reverse auction approach together with a multiple-buyer price discovery process

  5. Curative effect of sesame oil in a rat model of chronic kidney disease.

    Science.gov (United States)

    Liu, Chuan-Teng; Chien, Se-Ping; Hsu, Dur-Zong; Periasamy, Srinivasan; Liu, Ming-Yie

    2015-12-01

    Chronic kidney disease causes a progressive and irreversible loss of renal function. We investigated the curative effect of sesame oil, a natural, nutrient-rich, potent antioxidant, in a rat model of chronic kidney disease. Chronic kidney disease was induced by subcutaneously injecting uni-nephrectomized rats with deoxycorticosterone acetate (DOCA) and 1% NaCl [DOCA/salt] in drinking water. Four weeks later, the rats were gavaged with sesame oil (0.5 or 1 mL/kg per day) for 7 days. Renal injury, histopathological changes, hydroxyl radical, peroxynitrite, lipid peroxidation, Nrf2, osteopontin expression, and collagen were assessed 24 h after the last dose of sesame oil. Blood urea nitrogen, creatinine, urine volume, and albuminuria were significantly higher in the DOCA/salt treated rats than in control rats. Sesame oil significantly decreased these four tested parameters in DOCA/salt treated rats. In addition, creatinine clearance rate and nuclear Nrf2 expression were significantly decreased in the DOCA/salt treated rats compared to control rats. Sesame oil significantly decreased hydroxyl radical, peroxynitrite level, lipid peroxidation, osteopontin, and renal collagen deposition, but increased creatinine clearance rate and nuclear Nrf2 expression in DOCA/salt treated rats. We conclude that supplementation of sesame oil mitigates DOCA/salt induced chronic kidney disease in rats by activating Nrf2 and attenuating osteopontin expression and inhibiting renal fibrosis in rats. © 2015 Asian Pacific Society of Nephrology.

  6. Rheumatoid arthritis: identifying and characterising polymorphisms using rat models

    Science.gov (United States)

    2016-01-01

    ABSTRACT Rheumatoid arthritis is a chronic inflammatory joint disorder characterised by erosive inflammation of the articular cartilage and by destruction of the synovial joints. It is regulated by both genetic and environmental factors, and, currently, there is no preventative treatment or cure for this disease. Genome-wide association studies have identified ∼100 new loci associated with rheumatoid arthritis, in addition to the already known locus within the major histocompatibility complex II region. However, together, these loci account for only a modest fraction of the genetic variance associated with this disease and very little is known about the pathogenic roles of most of the risk loci identified. Here, we discuss how rat models of rheumatoid arthritis are being used to detect quantitative trait loci that regulate different arthritic traits by genetic linkage analysis and to positionally clone the underlying causative genes using congenic strains. By isolating specific loci on a fixed genetic background, congenic strains overcome the challenges of genetic heterogeneity and environmental interactions associated with human studies. Most importantly, congenic strains allow functional experimental studies be performed to investigate the pathological consequences of natural genetic polymorphisms, as illustrated by the discovery of several major disease genes that contribute to arthritis in rats. We discuss how these advances have provided new biological insights into arthritis in humans. PMID:27736747

  7. Magnetic resonance spectroscopy of traumatic brain in SD rats model

    International Nuclear Information System (INIS)

    Li Ke; Li Yangbin; Li Zhiming; Huang Yong; Li Bin; Lu Guangming

    2009-01-01

    Objective: To assess the value and prospect of magnetic resonance spectroscopy (MRS) in early diagnosis of traumatic brain with traumatic brain model in SD rats. Methods: Traumatic brain modal was established in 40 male SD rats utilizing a weigh-drop device, and MRS was performed before trauma and 4,8,24 and 48 hours after trauma. The ratio of N-acetylaspartate/creatine (NAA/Ct) and choline/creatine (Cho/Cr) were calculated and compared with pathological findings respectively. Results: Axonal changes were confirmed in microscopic study 4 hours after injury. The ratio of NAA/Ct decreased distinctly at 4 hours after trauma, followed by a steadily recover at 8 hours, and no significant change from 24h to 48h. There was no significant change in the ratio of Cho/Cr before and after trauma. Conclusion: MRS can be used to monitor the metabolic changes of brain non-invasively. MRS could play a positive role in early diagnosis, prognosis and follow-up of traumatic brain. (authors)

  8. A new model of progressive pulmonary fibrosis in rats

    Energy Technology Data Exchange (ETDEWEB)

    Last, J.A.; Gelzleichter, T.R.; Pinkerton, K.E.; Walker, R.M.; Witschi, H. (Univ. of California, Davis (United States))

    1993-08-01

    Sprague-Dawley rats were exposed for 6 h daily to 0.8 ppm of ozone and 14.4 ppm of nitrogen dioxide. Approximately 7 to 10 wk after the initiation of exposure, animals began to demonstrate respiratory insufficiency and severe weight loss. About half of the rats died between Days 55 and 78 of exposure; no overt ill effects were observed in animals exposed to filtered air, to ozone alone, or to nitrogen dioxide. Biochemical findings in animals exposed to ozone and nitrogen dioxide included increased lung content of DNA, protein, collagen, and elastin, which was about 300% higher than the control values. The collagen-specific crosslink hydroxy-pyridinium, a biomarker for mature collagen in the lung, was decreased by about 40%. These results are consistent with extensive breakdown and remodeling of the lung parenchyma and its associated vasculature. Histopathologic evaluation showed severe fibrosis, alveolar collapse, honeycombing, macrophage and mast cell accumulation, vascular smooth muscle hypertrophy, and other indications of severe progressive interstitial pulmonary fibrosis and end-stage lung disease. This unique animal model of progressive pulmonary fibrosis resembles the final stages of human idiopathic pulmonary fibrosis and should facilitate studying underlying mechanisms and potential therapy of progressive pulmonary fibrosis.

  9. Numerical model of the plasma formation at electron beam welding

    Energy Technology Data Exchange (ETDEWEB)

    Trushnikov, D. N., E-mail: trdimitr@yandex.ru [The Department for Applied Physics, Perm National Research Polytechnic University, Perm 614990 (Russian Federation); The Department for Welding Production and Technology of Constructional Materials, Perm National Research Polytechnic University, Perm 614990 (Russian Federation); Mladenov, G. M., E-mail: gmmladenov@abv.bg [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tzarigradsko Shose, 1784 Sofia (Bulgaria); Technology Centre of Electron Beam and Plasma Technologies and Techniques, 68-70 Vrania, ap.10, Banishora, 1309 Sofia (Bulgaria)

    2015-01-07

    The model of plasma formation in the keyhole in liquid metal as well as above the electron beam welding zone is described. The model is based on solution of two equations for the density of electrons and the mean electron energy. The mass transfer of heavy plasma particles (neutral atoms, excited atoms, and ions) is taken into account in the analysis by the diffusion equation for a multicomponent mixture. The electrostatic field is calculated using the Poisson equation. Thermionic electron emission is calculated for the keyhole wall. The ionization intensity of the vapors due to beam electrons and high-energy secondary and backscattered electrons is calibrated using the plasma parameters when there is no polarized collector electrode above the welding zone. The calculated data are in good agreement with experimental data. Results for the plasma parameters for excitation of a non-independent discharge are given. It is shown that there is a need to take into account the effect of a strong electric field near the keyhole walls on electron emission (the Schottky effect) in the calculation of the current for a non-independent discharge (hot cathode gas discharge). The calculated electron drift velocities are much bigger than the velocity at which current instabilities arise. This confirms the hypothesis for ion-acoustic instabilities, observed experimentally in previous research.

  10. Wendan decoction improves learning and memory deficits in a rat model of schizophrenia

    Institute of Scientific and Technical Information of China (English)

    Cuiping Yang; Changchun Cai; Xiaojin Yang; Yanping Yang; Zhigang Zhou; Jianhua Liu; Heping Ye; Hongjiao Wan

    2012-01-01

    An experimental model of schizophrenia was established using dizocilpine (MK-801). Rats were intragastrically administered with Wendan decoction or clozapine for 21 days prior to establishing the model. The results revealed that the latency of schizophrenia model rats to escape from the hidden platform in the Morris water maze was significantly shortened after administration of Wendan decoction or clozapine. In addition, the treated rats crossed the platform significantly more times than the untreated model rats. Moreover, the rate of successful long-term potentiation induction in the Wendan decoction group and clozapine group were also obviously increased compared with the model group, and the population spike peak latency was significantly shortened. These experimental findings suggest that Wendan decoction can improve the learning and memory ability of schizophrenic rats to the same extent as clozapine treatment.

  11. Characterization of the Prediabetic State in a Novel Rat Model of Type 2 Diabetes, the ZFDM Rat.

    Science.gov (United States)

    Gheni, Ghupurjan; Yokoi, Norihide; Beppu, Masayuki; Yamaguchi, Takuro; Hidaka, Shihomi; Kawabata, Ayako; Hoshino, Yoshikazu; Hoshino, Masayuki; Seino, Susumu

    2015-01-01

    We recently established a novel animal model of obese type 2 diabetes (T2D), the Zucker fatty diabetes mellitus (ZFDM) rat strain harboring the fatty mutation (fa) in the leptin receptor gene. Here we performed a phenotypic characterization of the strain, focusing mainly on the prediabetic state. At 6-8 weeks of age, fa/fa male rats exhibited mild glucose intolerance and severe insulin resistance. Although basal insulin secretion was remarkably high in the isolated pancreatic islets, the responses to both glucose stimulation and the incretin GLP-1 were retained. At 10-12 weeks of age, fa/fa male rats exhibited marked glucose intolerance as well as severe insulin resistance similar to that at the earlier age. In the pancreatic islets, the insulin secretory response to glucose stimulation was maintained but the response to the incretin was diminished. In nondiabetic Zucker fatty (ZF) rats, the insulin secretory responses to both glucose stimulation and the incretin in the pancreatic islets were similar to those of ZFDM rats. As islet architecture was destroyed with age in ZFDM rats, a combination of severe insulin resistance, diminished insulin secretory response to incretin, and intrinsic fragility of the islets may cause the development of T2D in this strain.

  12. Altered explorative strategies and reactive coping style in the FSL rat model of depression

    Directory of Open Access Journals (Sweden)

    Salvatore eMagara

    2015-04-01

    Full Text Available Modeling depression in animals is based on the observation of behaviors interpreted as analogue to human symptoms. Typical tests used in experimental depression research are designed to evoke an either-or outcome. It is known that explorative and coping strategies are relevant for depression, however these aspects are generally not considered in animal behavioral testing. Here we investigate the Flinders Sensitive Line (FSL, a rat model of depression, compared to the Sprague-Dawley (SD rat in three independent tests where the animals are allowed to express a more extensive behavioral repertoire. The multivariate concentric square field™ (MCSF and the novel cage tests evoke exploratory behaviors in a novel environment and the home cage change test evokes social behaviors in the re-establishment of a social hierarchy. In the MCSF test, FSL rats exhibited less exploratory drive and more risk-assessment behavior compared to SD rats. When re-exposed to the arena, FSL, but not SD rats, increased their exploratory behavior compared to the first trial and displayed risk-assessment behavior to the same extent as SD rats. Thus, the behavior of FSL rats was more similar to that of SDs when the rats were familiar with the arena. In the novel cage test FSL rats exhibited a reactive coping style, consistent with the reduced exploration observed in the MCSF. Reactive coping is associated with less aggressive behavior. Accordingly, FSL rats displayed less aggressive behavior in the home cage change test. Taken together, our data show that FSL rats express altered explorative behavior and reactive coping style. Reduced interest is a core symptom of depression, and individuals with a reactive coping style are more vulnerable to the disease. Our results support the use of FSL rats as an animal model of depression and increase our understanding of the FSL rat beyond the behavioral dimensions targeted by the traditional depression-related tests.

  13. Electron correlations in narrow energy bands: modified polar model approach

    Directory of Open Access Journals (Sweden)

    L. Didukh

    2008-09-01

    Full Text Available The electron correlations in narrow energy bands are examined within the framework of the modified form of polar model. This model permits to analyze the effect of strong Coulomb correlation, inter-atomic exchange and correlated hopping of electrons and explain some peculiarities of the properties of narrow-band materials, namely the metal-insulator transition with an increase of temperature, nonlinear concentration dependence of Curie temperature and peculiarities of transport properties of electronic subsystem. Using a variant of generalized Hartree-Fock approximation, the single-electron Green's function and quasi-particle energy spectrum of the model are calculated. Metal-insulator transition with the change of temperature is investigated in a system with correlated hopping. Processes of ferromagnetic ordering stabilization in the system with various forms of electronic DOS are studied. The static conductivity and effective spin-dependent masses of current carriers are calculated as a function of electron concentration at various DOS forms. The correlated hopping is shown to cause the electron-hole asymmetry of transport and ferromagnetic properties of narrow band materials.

  14. A model for electron currents near a field null

    International Nuclear Information System (INIS)

    Stark, R.A.; Miley, G.H.

    1987-01-01

    The fluid approximation is invalid near a field null, since the local electron orbit size and the magnetic scale length are comparable. To model the electron currents in this region we propose a single equation of motion describing the bulk electron dynamics. The equation applies to the plasma within one thermal orbit size of the null. The region is treated as unmagnetized; electrons are accelerated by the inductive electric field and drag on ions; damping is provided by viscosity due to electrons and collisions with ions. Through variational calculations and a particle tracking code for electrons, the size of the terms in the equation of motion have been estimated. The resulting equation of motion combines with Faraday's Law to produce a governing equation which implicitly contains the self inductive field of the electrons. This governing equation predicts that viscosity prevents complete cancellation of the ion current density by the electrons in the null region. Thus electron dynamics near the field null should not prevent the formation and deepening of field reversal using neutral-beam injection

  15. Intermittent Administration of Parathyroid Hormone [1-34] Prevents Particle-Induced Periprosthetic Osteolysis in a Rat Model.

    Directory of Open Access Journals (Sweden)

    Fanggang Bi

    Full Text Available We examined whether intermittent administration of parathyroid hormone [1-34] (PTH[1-34]; 60 μg/kg/day can prevent the negative effects of titanium (Ti particles on implant fixation and periprosthetic osteolysis in a rat model. Eighteen adult male rats (12 weeks old, bones still growing received intramedullary Ti implants in their bilateral femurs; 6 rats from the blank group received vehicle injections, and 12 rats from the control group and PTH treatment group received Ti particle injections at the time of operation and intra-articular injections 2 and 4 weeks postoperatively. Six of the rats that received Ti particles from the PTH group also received PTH[1-34] treatment. Six weeks postoperatively, all specimens were collected for assessment by X-ray, micro-CT, biomechanical, scanning electron microscopy (SEM, and dynamic histomorphometry. A lower BMD, BV/TV, Tb.N, maximal fixation strength, and mineral apposition rate were observed in the control group compared to the blank group, demonstrating that a periprosthetic osteolysis model had been successfully established. Administration of PTH[1-34] significantly increased the bone mineral density of the distal femur, BV/TV, Tb.N, Tb.Th, Tb.Sp, Con.D, SMI, and maximal fixation strength in the PTH group compared to that in the control group. SEM revealed higher bone-implant contact, thicker lamellar bone, and larger trabecular bone area in the PTH group than in the control group. A higher mineral apposition rate was observed in the PTH group compared to both the blank and control groups. These findings imply that intermittent administration of PTH[1-34] prevents periprosthetic osteolysis by promoting bone formation. The effects of PTH[1-34] were evaluated at a suprapharmacological dosage to the human equivalent in rats; therefore, additional studies are required to demonstrate its therapeutic potential in periprosthetic osteolysis.

  16. Bioburden Increases Heterotopic Ossification Formation in an Established Rat Model.

    Science.gov (United States)

    Pavey, Gabriel J; Qureshi, Ammar T; Hope, Donald N; Pavlicek, Rebecca L; Potter, Benjamin K; Forsberg, Jonathan A; Davis, Thomas A

    2015-09-01

    Heterotopic ossification (HO) develops in a majority of combat-related amputations wherein early bacterial colonization has been considered a potential early risk factor. Our group has recently developed a small animal model of trauma-induced HO that incorporates many of the multifaceted injury patterns of combat trauma in the absence of bacterial contamination and subsequent wound colonization. We sought to determine if (1) the presence of bioburden (Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus [MRSA]) increases the magnitude of ectopic bone formation in traumatized muscle after amputation; and (2) what persistent effects bacterial contamination has on late microbial flora within the amputation site. Using a blast-related HO model, we exposed 48 rats to blast overpressure, femur fracture, crush injury, and subsequent immediate transfemoral amputation through the zone of injury. Control injured rats (n = 8) were inoculated beneath the myodesis with phosphate-buffered saline not containing bacteria (vehicle) and treatment rats were inoculated with 1 × 10(6) colony-forming units of A baumannii (n = 20) or MRSA (n = 20). All animals formed HO. Heterotopic ossification was determined by quantitative volumetric measurements of ectopic bone at 12-weeks postinjury using micro-CT and qualitative histomorphometry for assessment of new bone formation in the residual limb. Bone marrow and muscle tissue biopsies were collected from the residual limb at 12 weeks to quantitatively measure the bioburden load and to qualitatively determine the species-level identification of the bacterial flora. At 12 weeks, we observed a greater volume of HO in rats infected with MRSA (68.9 ± 8.6 mm(3); 95% confidence interval [CI], 50.52-85.55) when compared with A baumannii (20.9 ± 3.7 mm(3); 95% CI, 13.61-28.14; p infection but were positive for other strains of bacteria (1.33 × 10(2) ± 0.89 × 10(2); 95% CI, -0.42 × 10(2)-3.08 × 10(2) and 1.25 × 10(6) ± 0

  17. Prediction Model for Relativistic Electrons at Geostationary Orbit

    Science.gov (United States)

    Khazanov, George V.; Lyatsky, Wladislaw

    2008-01-01

    We developed a new prediction model for forecasting relativistic (greater than 2MeV) electrons, which provides a VERY HIGH correlation between predicted and actually measured electron fluxes at geostationary orbit. This model implies the multi-step particle acceleration and is based on numerical integrating two linked continuity equations for primarily accelerated particles and relativistic electrons. The model includes a source and losses, and used solar wind data as only input parameters. We used the coupling function which is a best-fit combination of solar wind/interplanetary magnetic field parameters, responsible for the generation of geomagnetic activity, as a source. The loss function was derived from experimental data. We tested the model for four year period 2004-2007. The correlation coefficient between predicted and actual values of the electron fluxes for whole four year period as well as for each of these years is stable and incredibly high (about 0.9). The high and stable correlation between the computed and actual electron fluxes shows that the reliable forecasting these electrons at geostationary orbit is possible.

  18. Effectiveness of Saccharomyces boulardii in a rat model of colitis.

    Science.gov (United States)

    Soyturk, Mujde; Saygili, Saba Mukaddes; Baskin, Huseyin; Sagol, Ozgul; Yilmaz, Osman; Saygili, Fatih; Akpinar, Hale

    2012-11-28

    To investigate the effects of Saccharomyces boulardii (S. boulardii) in an experimental rat model of trinitrobenzene sulfonic acid (TNBS)-induced colitis. Thirty-two Wistar albino female rats were categorized into five groups. On the first day of the study, 50 mg TNBS was administered via a rectal catheter in order to induce colitis in all rats, except those in the control group. For 14 d, the rats were fed a standard diet, without the administration of any additional supplements to either the control or TNBS groups, in addition to 1 mg/kg per day S. boulardii to the S. boulardii group, 1 mg/kg per day methyl prednisolone (MP) to the MP group. The animals in the S. boulardii + MP group were coadministered these doses of S. boulardii and MP. During the study, weight loss, stool consistency, and the presence of obvious blood in the stool were evaluated, and the disease activity index (DAI) for colitis was recorded. The intestines were examined and colitis was macro- and microscopically scored. The serum and tissue levels of tumor necrosis factor-α (TNF-α) and nitric oxide (NO) were determined, and fungemia was evaluated in the blood samples. The mean DAI scores for the MP and S. boulardii + MP groups was significantly lower than the TNBS group (3.69 ± 0.61 vs 4.46 ± 0.34, P = 0.018 and 3.77 ± 0.73 vs 4.46 ± 0.34, P = 0.025, respectively). While no significant differences between the TNBS and the S. boulardii or MP groups could be determined in terms of serum NO levels, the level of serum NO in the S. boulardii + MP group was significantly higher than in the TNBS and S. boulardii groups (8.12 ± 4.25 μmol/L vs 3.18 ± 1.19 μmol/L, P = 0.013; 8.12 ± 4.25 μmol/L vs 3.47 ± 1.66 μmol/L, P = 0.012, respectively). The tissue NO levels in the S. boulardii, MP and S. boulardii + MP groups were significantly lower than the TNBS group (16.62 ± 2.27 μmol/L vs 29.72 ± 6.10 μmol/L, P = 0.002; 14.66 ± 5.18 μmol/L vs 29.72 ± 6.10 μmol/L, P = 0.003; 11.95 ± 2

  19. Modeling the customer in electronic commerce.

    Science.gov (United States)

    Helander, M G; Khalid, H M

    2000-12-01

    This paper reviews interface design of web pages for e-commerce. Different tasks in e-commerce are contrasted. A systems model is used to illustrate the information flow between three subsystems in e-commerce: store environment, customer, and web technology. A customer makes several decisions: to enter the store, to navigate, to purchase, to pay, and to keep the merchandize. This artificial environment must be designed so that it can support customer decision-making. To retain customers it must be pleasing and fun, and create a task with natural flow. Customers have different needs, competence and motivation, which affect decision-making. It may therefore be important to customize the design of the e-store environment. Future ergonomics research will have to investigate perceptual aspects, such as presentation of merchandize, and cognitive issues, such as product search and navigation, as well as decision making while considering various economic parameters. Five theories on e-commerce research are presented.

  20. Modeling of Jupiter's electron an ion radiation belts

    International Nuclear Information System (INIS)

    Sicard, Angelica

    2004-01-01

    In the Fifties, James Van Allen showed the existence of regions of the terrestrial magnetosphere consisted of energetic particles, trapped by the magnetic field: the radiation belts. The radiation belts of the Earth were the subject of many modeling works and are studied since several years at the Departement Environnement Spatial (DESP) of ONERA. In 1998, the DESP decided to adapt the radiation belts model of the Earth, Salammbo, to radiation environment of Jupiter. A first thesis was thus carried out on the subject and a first radiation belts model of electrons of Jupiter was developed [Santos-Costa, 2001]. The aim of this second thesis is to develop a radiation belts model for protons and heavy ions. In order to validate the developed model, the comparisons between Salammbo results and observations are essential. However, the validation is difficult in the case of protons and heavy ions because in-situ measurements of the probes are very few and most of the time contaminated by very energetic electrons. To solve this problem, a very good model of electrons radiation belts is essential to confirm or cancel the contamination of protons and heavy ions measurements. Thus, in parallel to the development of the protons and heavy ions radiation belts model, the electrons models, already existing, has been improved. Then Salammbo results have been compared to the different observations available (in-situ measurements, radio-astronomical observations). The different comparisons show a very good agreement between Salammbo results and observations. (author) [fr

  1. Spin delocalization phase transition in a correlated electrons model

    International Nuclear Information System (INIS)

    Huerta, L.

    1990-11-01

    In a simplified one-site model for correlated electrons systems we show the existence of a phase transition corresponding to spin delocalization. The system becomes a solvable model and zero-dimensional functional techniques are used. (author). 7 refs, 3 figs

  2. Modeling paraxial wave propagation in free-electron laser oscillators

    NARCIS (Netherlands)

    Karssenberg, J.G.; van der Slot, Petrus J.M.; Volokhine, I.; Verschuur, Jeroen W.J.; Boller, Klaus J.

    2006-01-01

    Modeling free-electron laser (FEL) oscillators requires calculation of both the light-beam interaction within the undulator and the light propagation outside the undulator. We have developed a paraxial optical propagation code that can be combined with various existing models of gain media, for

  3. Clinical and pathological manifestations of cardiovascular disease in rat models: the influence of acute ozone exposure

    Science.gov (United States)

    This paper shows that rat models of cardiovascular diseases have differential degrees of underlying pathologies at a young age. Rodent models of cardiovascular diseases (CVD) and metabolic disorders are used for examining susceptibility variations to environmental exposures. How...

  4. Efficacy of integrative medicine in deficiency of both qi and yin in the rat model of type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Jing Zhao

    2015-10-01

    Conclusions: A rat model of T2DM with both qi and yin deficiency was successfully replicated. CHF appeared to be more efficacious than IM and PIO in the rat model of qi and yin deficiency pattern of T2DM, though IM and PIO were each found to have their merits and drawbacks in attenuating T2DM indicators in the rat model.

  5. A rat uterine horn model of genital tract wound healing.

    Science.gov (United States)

    Schlaff, W D; Cooley, B C; Shen, W; Gittlesohn, A M; Rock, J A

    1987-11-01

    A rat uterine horn model of genital tract wound healing is described. Healing was reflected by acquisition of strength and elasticity, measured by burst strength (BS) and extensibility (EX), respectively. A tensiometer (Instron Corp., Canton, MA) was used to assess these characteristics in castrated and estrogen-supplemented or nonsupplemented animals. While the horn weights (HW), BS, and EX of contralateral horns were not significantly different, the intra-animal variation of HW was 7.2%, BS was 17.7% and EX was 38.2%. In a second experiment, one uterine horn was divided and anastomosed, and the animal given estrogen supplementation or a placebo pellet. Estrogen administration was found to increase BS and EX of anastomosed horns prior to 14 days, but had no beneficial effect at 21 or 42 days. The data suggest that estrogen may be required for optimal early healing of genital tract wounds.

  6. Modelling hot electron generation in short pulse target heating experiments

    Directory of Open Access Journals (Sweden)

    Sircombe N.J.

    2013-11-01

    Full Text Available Target heating experiments planned for the Orion laser facility, and electron beam driven fast ignition schemes, rely on the interaction of a short pulse high intensity laser with dense material to generate a flux of energetic electrons. It is essential that the characteristics of this electron source are well known in order to inform transport models in radiation hydrodynamics codes and allow effective evaluation of experimental results and forward modelling of future campaigns. We present results obtained with the particle in cell (PIC code EPOCH for realistic target and laser parameters, including first and second harmonic light. The hot electron distributions are characterised and their implications for onward transport and target heating are considered with the aid of the Monte-Carlo transport code THOR.

  7. Density-dependent electron transport and precise modeling of GaN high electron mobility transistors

    Energy Technology Data Exchange (ETDEWEB)

    Bajaj, Sanyam, E-mail: bajaj.10@osu.edu; Shoron, Omor F.; Park, Pil Sung; Krishnamoorthy, Sriram; Akyol, Fatih; Hung, Ting-Hsiang [Department of Electrical and Computer Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Reza, Shahed; Chumbes, Eduardo M. [Raytheon Integrated Defense Systems, Andover, Massachusetts 01810 (United States); Khurgin, Jacob [Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Rajan, Siddharth [Department of Electrical and Computer Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Department of Material Science and Engineering, The Ohio State University, Columbus, Ohio 43210 (United States)

    2015-10-12

    We report on the direct measurement of two-dimensional sheet charge density dependence of electron transport in AlGaN/GaN high electron mobility transistors (HEMTs). Pulsed IV measurements established increasing electron velocities with decreasing sheet charge densities, resulting in saturation velocity of 1.9 × 10{sup 7 }cm/s at a low sheet charge density of 7.8 × 10{sup 11 }cm{sup −2}. An optical phonon emission-based electron velocity model for GaN is also presented. It accommodates stimulated longitudinal optical (LO) phonon emission which clamps the electron velocity with strong electron-phonon interaction and long LO phonon lifetime in GaN. A comparison with the measured density-dependent saturation velocity shows that it captures the dependence rather well. Finally, the experimental result is applied in TCAD-based device simulator to predict DC and small signal characteristics of a reported GaN HEMT. Good agreement between the simulated and reported experimental results validated the measurement presented in this report and established accurate modeling of GaN HEMTs.

  8. Density-dependent electron transport and precise modeling of GaN high electron mobility transistors

    International Nuclear Information System (INIS)

    Bajaj, Sanyam; Shoron, Omor F.; Park, Pil Sung; Krishnamoorthy, Sriram; Akyol, Fatih; Hung, Ting-Hsiang; Reza, Shahed; Chumbes, Eduardo M.; Khurgin, Jacob; Rajan, Siddharth

    2015-01-01

    We report on the direct measurement of two-dimensional sheet charge density dependence of electron transport in AlGaN/GaN high electron mobility transistors (HEMTs). Pulsed IV measurements established increasing electron velocities with decreasing sheet charge densities, resulting in saturation velocity of 1.9 × 10 7  cm/s at a low sheet charge density of 7.8 × 10 11  cm −2 . An optical phonon emission-based electron velocity model for GaN is also presented. It accommodates stimulated longitudinal optical (LO) phonon emission which clamps the electron velocity with strong electron-phonon interaction and long LO phonon lifetime in GaN. A comparison with the measured density-dependent saturation velocity shows that it captures the dependence rather well. Finally, the experimental result is applied in TCAD-based device simulator to predict DC and small signal characteristics of a reported GaN HEMT. Good agreement between the simulated and reported experimental results validated the measurement presented in this report and established accurate modeling of GaN HEMTs

  9. Modeling electron fractionalization with unconventional Fock spaces.

    Science.gov (United States)

    Cobanera, Emilio

    2017-08-02

    It is shown that certain fractionally-charged quasiparticles can be modeled on D-dimensional lattices in terms of unconventional yet simple Fock algebras of creation and annihilation operators. These unconventional Fock algebras are derived from the usual fermionic algebra by taking roots (the square root, cubic root, etc) of the usual fermionic creation and annihilation operators. If the fermions carry non-Abelian charges, then this approach fractionalizes the Abelian charges only. In particular, the mth-root of a spinful fermion carries charge e/m and spin 1/2. Just like taking a root of a complex number, taking a root of a fermion yields a mildly non-unique result. As a consequence, there are several possible choices of quantum exchange statistics for fermion-root quasiparticles. These choices are tied to the dimensionality [Formula: see text] of the lattice by basic physical considerations. One particular family of fermion-root quasiparticles is directly connected to the parafermion zero-energy modes expected to emerge in certain mesoscopic devices involving fractional quantum Hall states. Hence, as an application of potential mesoscopic interest, I investigate numerically the hybridization of Majorana and parafermion zero-energy edge modes caused by fractionalizing but charge-conserving tunneling.

  10. USign--a security enhanced electronic consent model.

    Science.gov (United States)

    Li, Yanyan; Xie, Mengjun; Bian, Jiang

    2014-01-01

    Electronic consent becomes increasingly popular in the healthcare sector given the many benefits it provides. However, security concerns, e.g., how to verify the identity of a person who is remotely accessing the electronic consent system in a secure and user-friendly manner, also arise along with the popularity of electronic consent. Unfortunately, existing electronic consent systems do not pay sufficient attention to those issues. They mainly rely on conventional password based authentication to verify the identity of an electronic consent user, which is far from being sufficient given that identity theft threat is real and significant in reality. In this paper, we present a security enhanced electronic consent model called USign. USign enhances the identity protection and authentication for electronic consent systems by leveraging handwritten signatures everyone is familiar with and mobile computing technologies that are becoming ubiquitous. We developed a prototype of USign and conducted preliminary evaluation on accuracy and usability of signature verification. Our experimental results show the feasibility of the proposed model.

  11. Aberrant Pregnancy Adaptations in the Peripheral Immune Response in Type 1 Diabetes: A Rat Model.

    Directory of Open Access Journals (Sweden)

    Bart Groen

    Full Text Available Despite tight glycemic control, pregnancy complication rate in type 1 diabetes patients is higher than in normal pregnancy. Other etiological factors may be responsible for the development of adverse pregnancy outcome. Acceptance of the semi-allogeneic fetus is accompanied by adaptations in the maternal immune-response. Maladaptations of the immune-response has been shown to contribute to pregnancy complications. We hypothesized that type 1 diabetes, as an autoimmune disease, may be associated with maladaptations of the immune-response to pregnancy, possibly resulting in pregnancy complications.We studied pregnancy outcome and pregnancy-induced immunological adaptations in a normoglycemic rat-model of type 1 diabetes, i.e. biobreeding diabetes-prone rats (BBDP; 5 non-pregnant rats, 7 pregnant day 10 rats and 6 pregnant day 18 rats , versus non-diabetic control rats (i.e. congenic non-diabetic biobreeding diabetes-resistant (BBDR; 6 non-pregnant rats, 6 pregnant day 10 rats and 6 pregnant day 18 rats and Wistar-rats (6 non-pregnant, 6 pregnant day 10 rats and 5 pregnant day 18 rats.We observed reduced litter size, lower fetal weight of viable fetuses and increased numbers of resorptions versus control rats. These complications are accompanied by various differences in the immune-response between BBDP and control rats in both pregnant and non-pregnant animals. The immune-response in non-pregnant BBDP-rats was characterized by decreased percentages of lymphocytes, increased percentages of effector T-cells, regulatory T-cells and natural killer cells, an increased Th1/Th2-ratio and activated monocytes versus Wistar and BBDR-rats. Furthermore, pregnancy-induced adaptations in BBDP-rats coincided with an increased Th1/Th2-ratio, a decreased mean fluorescence intensity CD161a/NKR-P1b ratio and no further activation of monocytes versus non-diabetic control rats.This study suggests that even in the face of strict normoglycemia, pregnancy complications

  12. ELECTRONIC CIRCUIT BOARDS NON-UNIFORM COOLING SYSTEM MODEL

    Directory of Open Access Journals (Sweden)

    D. V. Yevdulov

    2016-01-01

    Full Text Available Abstract. The paper considers a mathematical model of non-uniform cooling of electronic circuit boards. The block diagram of the system implementing this approach, the method of calculation of the electronic board temperature field, as well as the principle of its thermal performance optimizing are presented. In the considered scheme the main heat elimination from electronic board is produced by the radiator system, and additional cooling of the most temperature-sensitive components is produced by thermoelectric batteries. Are given the two-dimensional temperature fields of the electronic board during its uniform and non-uniform cooling, is carried out their comparison. As follows from the calculations results, when using a uniform overall cooling of electronic unit there is a waste of energy for the cooling 0f electronic board parts which temperature is within acceptable temperature range without the cooling system. This approach leads to the increase in the cooling capacity of used thermoelectric batteries in comparison with the desired values. This largely reduces the efficiency of heat elimination system. The use for electronic boards cooling of non-uniform local heat elimination removes this disadvantage. The obtained dependences show that in this case, the energy required to create a given temperature is smaller than when using a common uniform cooling. In this approach the temperature field of the electronic board is more uniform and the cooling is more efficient. 

  13. Cyclosporin safety in a simplified rat brain tumor implantation model

    Directory of Open Access Journals (Sweden)

    Francisco H. C. Felix

    2012-01-01

    Full Text Available Brain cancer is the second neurological cause of death. A simplified animal brain tumor model using W256 (carcinoma 256, Walker cell line was developed to permit the testing of novel treatment modalities. Wistar rats had a cell tumor solution inoculated stereotactically in the basal ganglia (right subfrontal caudate. This model yielded tumor growth in 95% of the animals, and showed absence of extracranial metastasis and systemic infection. Survival median was 10 days. Estimated tumor volume was 17.08±6.7 mm³ on the 7th day and 67.25±19.8 mm³ on 9th day post-inoculation. Doubling time was 24.25 h. Tumor growth induced cachexia, but no hematological or biochemical alterations. This model behaved as an undifferentiated tumor and can be promising for studying tumor cell migration in the central nervous system. Dexamethasone 3.0 mg/kg/day diminished significantly survival in this model. Cyclosporine 10 mg/kg/day administration was safely tolerated.

  14. Tumorigenic action of beta, proton, alpha, and electron radiation on the rat skin. Progress report, August 1, 1974--July 31, 1975

    International Nuclear Information System (INIS)

    Albert, R.E.; Burns, F.J.

    1975-01-01

    The carcinogenic effects of ionizing radiation (α, β, electron, and protons) on rat skin were studied in an attempt to learn more about radiation carcinogenesis, especially how various parameters of the irradiation, such as dose distribution within the tissue and dose rate, affect the yield of tumors. It was found that when the dose was localized to a small region of skin, the tumor yield was reduced and the magnitude of the reduction indicated that the region of reduced response might extend about 150 μ into the irradiated zone. The proliferative state of the hair follicles at the time of irradiation had relatively little effect on tumor induction although old animals were less susceptible than young or newborn animals. The penetration requirement of at least 0.3 mm for producing tumors suggests that the hair follicle germ cells could be the oncogenic targets. Comprehensive experiments to measure the rate of recovery for tumor induction in split-dose exposure protocols indicated a recovery halftime of about 4 hrs for electrons and significant recovery for protons, which was used in a model to predict how recovery should affect the tumor response at low dose rates. Combinations of ionizing radiation and ultraviolet light were applied to rat skin to determine whether they are additive for producing tumors. (U.S.)

  15. A Model for Electronic Good Governance in Electronic Learning Sector of Iran

    Directory of Open Access Journals (Sweden)

    Alireza Moghaddasi

    2016-10-01

    Full Text Available Despite the various models and frameworks on electronic good governance are introduced, the multiple dimensions model of electronic good governance in the field of e-Learning has not been reviewed this subject in a integrated, comprehensive, process-oriented and systematic model. In this article, in order to explain the process of electronic good governance, by a systematic review of the related literature and backgrounds, all factors were identified using meta-synthesis methodology. Then, based on grounded theory methodology and Strauss and Corbin paradigmatic approach, the open, axial and selective coding were conducted. In the following, by using survey method, we determined the importance and priority of all proposed factors. It was also indicated that this research was innovative in the fields of methodology, results and the proposed model which had not been considered in the previous researches. So that, the proposed model resolved the shortcomings of past researches and made it possible for the public sector, private and civil society organizations to consider the process of establishing electronic good governance in e-Learning sector in Iran as a dynamic process.

  16. A ballistic transport model for electronic excitation following particle impact

    Science.gov (United States)

    Hanke, S.; Heuser, C.; Weidtmann, B.; Wucher, A.

    2018-01-01

    We present a ballistic model for the transport of electronic excitation energy induced by keV particle bombardment onto a solid surface. Starting from a free electron gas model, the Boltzmann transport equation (BTE) is employed to follow the evolution of the temporal and spatial distribution function f (r → , k → , t) describing the occupation probability of an electronic state k → at position r → and time t. Three different initializations of the distribution function are considered: i) a thermal distribution function with a locally and temporally elevated electron temperature, ii) a peak excitation at a specific energy above the Fermi level with a quasi-isotropic distribution in k-space and iii) an anisotropic peak excitation with k-vectors oriented in a specific transport direction. While the first initialization resembles a distribution function which may, for instance, result from electronic friction of moving atoms within an ion induced collision cascade, the peak excitation can in principle result from an autoionization process after excitation in close binary collisions. By numerically solving the BTE, we study the electronic energy exchange along a one dimensional transport direction to obtain a time and space resolved excitation energy distribution function, which is then analyzed in view of general transport characteristics of the chosen model system.

  17. Monte Carlo-based dose reconstruction in a rat model for scattered ionizing radiation investigations.

    Science.gov (United States)

    Kirkby, Charles; Ghasroddashti, Esmaeel; Kovalchuk, Anna; Kolb, Bryan; Kovalchuk, Olga

    2013-09-01

    In radiation biology, rats are often irradiated, but the precise dose distributions are often lacking, particularly in areas that receive scatter radiation. We used a non-dedicated set of resources to calculate detailed dose distributions, including doses to peripheral organs well outside of the primary field, in common rat exposure settings. We conducted a detailed dose reconstruction in a rat through an analog to the conventional human treatment planning process. The process consisted of: (i) Characterizing source properties of an X-ray irradiator system, (ii) acquiring a computed tomography (CT) scan of a rat model, and (iii) using a Monte Carlo (MC) dose calculation engine to generate the dose distribution within the rat model. We considered cranial and liver irradiation scenarios where the rest of the body was protected by a lead shield. Organs of interest were the brain, liver and gonads. The study also included paired scenarios where the dose to adjacent, shielded rats was determined as a potential control for analysis of bystander effects. We established the precise doses and dose distributions delivered to the peripheral organs in single and paired rats. Mean doses to non-targeted organs in irradiated rats ranged from 0.03-0.1% of the reference platform dose. Mean doses to the adjacent rat peripheral organs were consistent to within 10% those of the directly irradiated rat. This work provided details of dose distributions in rat models under common irradiation conditions and established an effective scenario for delivering only scattered radiation consistent with that in a directly irradiated rat.

  18. Delayed bone regeneration and low bone mass in a rat model of insulin-resistant type 2 diabetes mellitus is due to impaired osteoblast function.

    Science.gov (United States)

    Hamann, Christine; Goettsch, Claudia; Mettelsiefen, Jan; Henkenjohann, Veit; Rauner, Martina; Hempel, Ute; Bernhardt, Ricardo; Fratzl-Zelman, Nadja; Roschger, Paul; Rammelt, Stefan; Günther, Klaus-Peter; Hofbauer, Lorenz C

    2011-12-01

    Patients with diabetes mellitus have an impaired bone metabolism; however, the underlying mechanisms are poorly understood. Here, we analyzed the impact of type 2 diabetes mellitus on bone physiology and regeneration using Zucker diabetic fatty (ZDF) rats, an established rat model of insulin-resistant type 2 diabetes mellitus. ZDF rats develop diabetes with vascular complications when fed a Western diet. In 21-wk-old diabetic rats, bone mineral density (BMD) was 22.5% (total) and 54.6% (trabecular) lower at the distal femur and 17.2% (total) and 20.4% (trabecular) lower at the lumbar spine, respectively, compared with nondiabetic animals. BMD distribution measured by backscattered electron imaging postmortem was not different between diabetic and nondiabetic rats, but evaluation of histomorphometric indexes revealed lower mineralized bone volume/tissue volume, trabecular thickness, and trabecular number. Osteoblast differentiation of diabetic rats was impaired based on lower alkaline phosphatase activity (-20%) and mineralized matrix formation (-55%). In addition, the expression of the osteoblast-specific genes bone morphogenetic protein-2, RUNX2, osteocalcin, and osteopontin was reduced by 40-80%. Osteoclast biology was not affected based on tartrate-resistant acidic phosphatase staining, pit formation assay, and gene profiling. To validate the implications of these molecular and cellular findings in a clinically relevant model, a subcritical bone defect of 3 mm was created at the left femur after stabilization with a four-hole plate, and bone regeneration was monitored by X-ray and microcomputed tomography analyses over 12 wk. While nondiabetic rats filled the defects by 57%, diabetic rats showed delayed bone regeneration with only 21% defect filling. In conclusion, we identified suppressed osteoblastogenesis as a cause and mechanism for low bone mass and impaired bone regeneration in a rat model of type 2 diabetes mellitus.

  19. Electron scattering studies by means of various nuclear models

    International Nuclear Information System (INIS)

    Essaniyazov, Sh.; Juraev, Sh.; Ismatov, E.I.

    2006-01-01

    transition of nucleus into the excited state in the region of the discrete spectrum (ω>0). The study of the scattered electrons energy spectrum directly allows separation of the excited energy levels. The study of the inelastic electrons scattering gives opportunity to establish possible application of various nuclear models. Quasi-elastic scattering. A wide maximum in the energy spectrum of the scattered electrons corresponds to the direct collisions of the electron with particular nucleons in nucleus. (author)

  20. Evaluation of Lercanidipine in Paclitaxel-Induced Neuropathic Pain Model in Rat: A Preliminary Study

    OpenAIRE

    Saha, Lekha; Hota, Debasish; Chakrabarti, Amitava

    2012-01-01

    Objective. To demonstrate the antinociceptive effect of lercanidipine in paclitaxel-induced neuropathy model in rat. Materials and Methods. A total of 30 rats were divided into five groups of six rats in each group as follows: Gr I: 0.9% NaCl, Gr II: paclitaxel + 0.9% NaCl, Gr III: paclitaxel + lercanidipine 0.5 μg/kg, Gr IV: paclitaxel + lercanidipine 1 μg/kg, and Gr V: paclitaxel + lercanidipine 2.5 μg/kg. Paclitaxel-induced neuropathic pain in rat was produced by single intraperitoneal (i....

  1. Probabilistic model for the simulation of secondary electron emission

    Directory of Open Access Journals (Sweden)

    M. A. Furman

    2002-12-01

    Full Text Available We provide a detailed description of a model and its computational algorithm for the secondary electron emission process. The model is based on a broad phenomenological fit to data for the secondary-emission yield and the emitted-energy spectrum. We provide two sets of values for the parameters by fitting our model to two particular data sets, one for copper and the other one for stainless steel.

  2. An automatic rat brain extraction method based on a deformable surface model.

    Science.gov (United States)

    Li, Jiehua; Liu, Xiaofeng; Zhuo, Jiachen; Gullapalli, Rao P; Zara, Jason M

    2013-08-15

    The extraction of the brain from the skull in medical images is a necessary first step before image registration or segmentation. While pre-clinical MR imaging studies on small animals, such as rats, are increasing, fully automatic imaging processing techniques specific to small animal studies remain lacking. In this paper, we present an automatic rat brain extraction method, the Rat Brain Deformable model method (RBD), which adapts the popular human brain extraction tool (BET) through the incorporation of information on the brain geometry and MR image characteristics of the rat brain. The robustness of the method was demonstrated on T2-weighted MR images of 64 rats and compared with other brain extraction methods (BET, PCNN, PCNN-3D). The results demonstrate that RBD reliably extracts the rat brain with high accuracy (>92% volume overlap) and is robust against signal inhomogeneity in the images. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Plasma hormones facilitated the hypermotility of the colon in a chronic stress rat model.

    Directory of Open Access Journals (Sweden)

    Chengbai Liang

    Full Text Available OBJECTIVE: To study the relationship between brain-gut peptides, gastrointestinal hormones and altered motility in a rat model of repetitive water avoidance stress (WAS, which mimics the irritable bowel syndrome (IBS. METHODS: Male Wistar rats were submitted daily to 1-h of water avoidance stress (WAS or sham WAS (SWAS for 10 consecutive days. Plasma hormones were determined using Enzyme Immunoassay Kits. Proximal colonic smooth muscle (PCSM contractions were studied in an organ bath system. PCSM cells were isolated by enzymatic digestion and IKv and IBKca were recorded by the patch-clamp technique. RESULTS: The number of fecal pellets during 1 h of acute restraint stress and the plasma hormones levels of substance P (SP, thyrotropin-releasing hormone (TRH, motilin (MTL, and cholecystokinin (CCK in WAS rats were significantly increased compared with SWAS rats, whereas vasoactive intestinal peptide (VIP, calcitonin gene-related peptide (CGRP and corticotropin releasing hormone (CRH in WAS rats were not significantly changed and peptide YY (PYY in WAS rats was significantly decreased. Likewise, the amplitudes of spontaneous contractions of PCSM in WAS rats were significantly increased comparing with SWAS rats. The plasma of WAS rats (100 µl decreased the amplitude of spontaneous contractions of controls. The IKv and IBKCa of PCSMs were significantly decreased in WAS rats compared with SWAS rats and the plasma of WAS rats (100 µl increased the amplitude of IKv and IBKCa in normal rats. CONCLUSION: These results suggest that WAS leads to changes of plasma hormones levels and to disordered myogenic colonic motility in the short term, but that the colon rapidly establishes a new equilibrium to maintain the normal baseline functioning.

  4. MRI and morphological observation in C6 glioma model rats and significance

    International Nuclear Information System (INIS)

    Zhou Ying; Yuan Bo; Wang Hao; Lu Jin; Yuan Changji; Ma Yue; Tong Dan; Zhang Kun; Gao Feng; Wu Xiaogang

    2013-01-01

    Objective: To establish stable and reliable rat C6 glioma model, and to perform MRI dynamic observation and pathomorphological observation in model animal brain, and to provide experimental basis for pharmaceutical research on anti-glioma drugs. Methods: The C6 glioma cells were cultured and 20 μL cultural fluid containing 1×10 6 C6 cells was sterotactically implanted into the left caudate nuclei in 10 male Wistar rats, respectively. The changes in the behavior of the rats after implantation were observed and recorded. MRI dynamic scanning was performed in 10 rats 2, 3 and 4 weeks after implantation and the brain tissues were taken for general and pathological examination when the 10 rats were naturally dead. The survival period of tumor-bearing rats was calculated. Results: 2 weeks after implantation the rats showed decreased activities and food intake, fur lackluster, and conjunctival congestion and so on; 3 weeks later, some rats appeared nerve symptoms such as body twitch, body hemiplegy, body distortion, rotation and so on. All the 10 rats died in 8-30 d. The median survival period of the tumor-bearing rats was 18 d, the average survival period was (18.3±7.3) d. The pathological examination showed that the tumor cells were arranged irregularly closely and karyokinesis was easy to see; tumor vascular tissue proliferation and tumor invasive growth into surrounding normal tissues were found. The expression of glial fibrillary acidic protein (GFAP) was positive in the tumors. Conclusion: A stable animal model of intracranial glioma is successfully established by stereotactic implantation of C6 cells into the rat caudate nucleus. The results of MRI dynamic observation and pathohistological observation on the model animal brain tissue. Can provide experimental basis for selecting the appropriate time window to perform the pharmaceutical research on anti-glioma drugs. (authors)

  5. Naked DNA Immunization for Prevention of Prostate Cancer in a Dunning Rat Prostate Tumor Model

    National Research Council Canada - National Science Library

    Mincheff, Milcho

    2003-01-01

    ...: H-PSMA-T, R-"PSMA"-T, H-PSA, H-PSA-T, H-PAP-T and R"PSMA"-S. Preliminary studies using the Copenhagen rat tumor prostate model showed uniform tumor development in rats that were injected subcutaneously with 100 000 AT3B-lPSMA,PSA cells...

  6. A RAT MODEL OF HEART FAILURE INDUCED BY ISOPROTERENOL AND A HIGH SALT DIET

    Science.gov (United States)

    Rat models of heart failure (HF) show varied pathology and time to disease outcome, dependent on induction method. We found that subchronic (4wk) isoproterenol (ISO) infusion in Spontaneously Hypertensive Heart Failure (SHHF) rats caused cardiac injury with minimal hypertrophy. O...

  7. The morphological effect of electron irradiation on the healing of skin wounds and skin grafts in the rat

    International Nuclear Information System (INIS)

    Wang, Q.

    1995-01-01

    Current oncological practice frequently uses pre-, intra- or post-operative radiotherapy/chemotherapy. Before such treatment can begin it is imperative to establish that satisfactory wound healing will occur. Many previous studies have examined the response of wound healing to ionizing and non-ionizing radiation. In general, clinical and experimental reports indicate that ionizing radiation produces poor to difficult healing of wounds, and can even prevent healing altogether. It is for this reason that the effect of radiation on wound repair has been a long standing concern for surgeons, radiotherapists and radiobiologists. Electron irradiation produces large differences in depth-dose distributions. This enables the delivery of a constant maximal dose throughout the superficial layer of tissue, for example, the total depth of skin, with less damage in deeper tissue layers, compared to that produced by the use of electromagnetic radiation such as X-rays. It is for this reason that electron beam irradiation has been selected as a radiation source for radiation of the graft bed. To date there have been few morphological examinations of the effect of electron radiation on the healing of skin wounds in rats. A review of the literature shows no information on the use of radiation of the graft bed in skin graft surgery. In the present work the processes involved in wound repair in response to radiation were studied, morphologically, using two experimental models, incisional wounds combined with pre-operative radiation and skin autografts combined with radiation of the wound bed. In the latter case an unirradiated skin graft was surgically attached to an irradiated wound bed. Light microscopy (LM), backscattered electron imaging (BEI), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used as investigative tools. These repair processes include inflammation, re-epithelialization, re-formation of the dermo-epidermal junction, re

  8. The morphological effect of electron irradiation on the healing of skin wounds and skin grafts in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Q

    1995-07-01

    Current oncological practice frequently uses pre-, intra- or post-operative radiotherapy/chemotherapy. Before such treatment can begin it is imperative to establish that satisfactory wound healing will occur. Many previous studies have examined the response of wound healing to ionizing and non-ionizing radiation. In general, clinical and experimental reports indicate that ionizing radiation produces poor to difficult healing of wounds, and can even prevent healing altogether. It is for this reason that the effect of radiation on wound repair has been a long standing concern for surgeons, radiotherapists and radiobiologists. Electron irradiation produces large differences in depth-dose distributions. This enables the delivery of a constant maximal dose throughout the superficial layer of tissue, for example, the total depth of skin, with less damage in deeper tissue layers, compared to that produced by the use of electromagnetic radiation such as X-rays. It is for this reason that electron beam irradiation has been selected as a radiation source for radiation of the graft bed. To date there have been few morphological examinations of the effect of electron radiation on the healing of skin wounds in rats. A review of the literature shows no information on the use of radiation of the graft bed in skin graft surgery. In the present work the processes involved in wound repair in response to radiation were studied, morphologically, using two experimental models, incisional wounds combined with pre-operative radiation and skin autografts combined with radiation of the wound bed. In the latter case an unirradiated skin graft was surgically attached to an irradiated wound bed. Light microscopy (LM), backscattered electron imaging (BEI), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used as investigative tools. These repair processes include inflammation, re-epithelialization, re-formation of the dermo-epidermal junction, re

  9. Bladder overdistension with polyuria in a hypertensive rat model.

    Science.gov (United States)

    Velasquez Flores, Monica; Mossa, Abubakr H; Cammisotto, Philippe; Campeau, Lysanne

    2018-03-31

    Polyuria can lead to progressive chronic bladder overdistension. The impact of polyuria on the bladder has been extensively studied in settings of either diabetes or sucrose diuresis in animals. The goal of this study was to investigate the outcomes of polyuria in a hypertension setting. Male Dahl/SS rats, a hypertension model, received a high-salt or normal diet for 6 weeks. Twenty-four-hour water intake, micturition patterns, and blood pressures were recorded biweekly. Conscious cystometry was carried out at the end of this period. Bladders were collected to measure contractile force and for histological analysis. Paired t-tests were used to compare changes between Week 0 and Week 6 within each group. Unpaired t-tests were used for comparisons between groups for all parameters at Week 6. Six weeks of high-salt diet significantly increased water intake and total urine. Blood pressures and volume of urine per micturition was higher in rats on high-salt diet. Bladder overdistension in the high-salt diet group was confirmed by cystometry, shown by a significantly higher bladder capacity, and compliance. No difference in detrusor contractility was observed between both groups. Collagen content was significantly higher in the lamina propria of the high-salt group compared to the normal group, while the opposite was observed in the muscularis. Polyuria, in a hypertension context, leads to changes in bladder morphology and function. These findings help clarify the deleterious clinical impact of polyuria on voiding function, highlighting the variable consequences of bladder overdistension according to the underlying pathology. © 2018 Wiley Periodicals, Inc.

  10. Modeling and Verification of Dependable Electronic Power System Architecture

    Science.gov (United States)

    Yuan, Ling; Fan, Ping; Zhang, Xiao-fang

    The electronic power system can be viewed as a system composed of a set of concurrently interacting subsystems to generate, transmit, and distribute electric power. The complex interaction among sub-systems makes the design of electronic power system complicated. Furthermore, in order to guarantee the safe generation and distribution of electronic power, the fault tolerant mechanisms are incorporated in the system design to satisfy high reliability requirements. As a result, the incorporation makes the design of such system more complicated. We propose a dependable electronic power system architecture, which can provide a generic framework to guide the development of electronic power system to ease the development complexity. In order to provide common idioms and patterns to the system *designers, we formally model the electronic power system architecture by using the PVS formal language. Based on the PVS model of this system architecture, we formally verify the fault tolerant properties of the system architecture by using the PVS theorem prover, which can guarantee that the system architecture can satisfy high reliability requirements.

  11. The characterization of obese polycystic ovary syndrome rat model suitable for exercise intervention.

    Directory of Open Access Journals (Sweden)

    Chuyan Wu

    Full Text Available To develop a new polycystic ovary syndrome (PCOS rat model suitable for exercise intervention.Thirty six rats were randomly divided into three experimental groups: PCOS rats with high-fat diet (PF, n = 24, PCOS rats with ordinary diet (PO, n = 6, and control rats with ordinary diet (CO, n = 6. Two kinds of PCOS rat model were made by adjustment diet structure and testosterone injection for 28 days. After a successful animal model, PF model rats were randomly assigned to three groups: exercise with a continuation of high-fat diet (PF-EF, n = 6, sedentary with a continuation of high-fat diet (PF-SF, n = 6, exercise with an ordinary diet (PF-EO, n = 6. Fasting blood glucose (FBG and insulin (FINS, estrogen (E2, progesterone (P, and testosterone (T in serum were determined by RIA, and ovarian morphology was evaluated by Image-Pro plus 6.0.Body weight, Lee index, FINS increased significantly in PF rat model. Serum levels of E2 and T were significantly higher in PF and PO than in CO. Ovary organ index and ovarian areas were significant lower in PF than in CO. After intervention for 2 weeks, the levels of 1 h postprandial blood glucose (PBG1, 2 h postprandial blood glucose (PBG2, FINS and the serum levels of T decreased significantly in PF-EF rats and PF-EO rats. The ratio of FBG/FINS was significant higher in PF-EO rats than in PF-SF rats. Ovarian morphology showed that the numbers of preantral follicles and atretic follicles decreased significantly, and the numbers of antral follicles and corpora lutea increased significantly in the rats of PF-EF and PF-EO.By combination of high-fat diet and testosterone injection, the obese PCOS rat model is conformable with the lifestyle habits of fatty foods and insufficient exercise, and has metabolic and reproductive characteristics of human PCOS. This model can be applied to study exercise intervention.

  12. Fundamental models of electronic transport in amorphous semiconductors

    International Nuclear Information System (INIS)

    Emin, D.

    1982-01-01

    Significant fundamental questions lie at the heart of our understanding of the electronic and optical properties of semiconducting and insulating glasses. In this article the principal features of the Mott-CFO model and the small-polaron model are described. While the Mott-CFO model seems to apply to the high-mobility electron transport in glassy SiO 2 and Cd 2 As 3 it does not appear applicable to the most frequently studied chalocogenide glasses. Furthermore, the Mott-CFO model does not account for as basic a feature as the sign of the Hall effect. On the other hand, the small-polaron model accounts for the observed d.c. conductivity, Peltier heat and Hall mobility in a very simple and direct manner

  13. Modeling the electron-proton telescope on Solar Orbiter

    Energy Technology Data Exchange (ETDEWEB)

    Boden, Sebastian; Steinhagen, Jan; Kulkarni, S.R.; Tammen, Jan; Elftmann, Robert; Martin, Cesar; Ravanbakhsh, Ali; Boettcher, Stephan; Seimetz, Lars; Wimmer-Schweingruber, Robert F. [Christian-Albrechts-Universitaet, Kiel (Germany)

    2014-07-01

    The Electron Proton Telescope (EPT) is one of four sensors in the Energetic Particle Detector suite for Solar Orbiter. It investigates low energy electrons and protons of solar events in an energy range from 20 - 400 keV for electrons and 20 keV - 7 MeV for protons. It distinguishes electrons from protons using a magnet/foil technique with silicon detectors. There will be two EPT units, each with double-barreled telescopes, one looking sunwards/antisunwards and the other north/south. We set up a Monte Carlo model of EPT using the GEANT4 framework, which we can use to simulate interactions of energetic particles in the sensor. Here we present simulation results of the energy coverage for different ion species, and we study how it is possible to distinguish between them.

  14. Status of the Galileo interim radiation electron model

    Science.gov (United States)

    Garrett, H. B.; Jun, I.; Ratliff, J. M.; Evans, R. W.; Clough, G. A.; McEntire, R. W.

    2003-04-01

    Measurements of the high energy, omni-directional electron environment by the Galileo spacecraft Energetic Particle Detector (EPD) were used to develop a new model of Jupiter's trapped electron radiation in the jovian equatorial plane for the range 8 to 16 Jupiter radii (1 jovian radius = 71,400 km). 10-minute averages of these data formed an extensive database of observations of the jovian radiation belts between Jupiter orbit insertion (JOI) in 1995 and 2002. These data were then averaged to provide a differential flux spectrum at 0.174, 0.304, 0.527, 1.5, 2.0, 11.0, and 31 MeV in the jovian equatorial plane as a function of radial distance. This omni-directional, equatorial model was combined with the original Divine model of jovian electron radiation to yield estimates of the out-of-plane radiation environment. That model, referred to here as the Galileo Interim Radiation Electron (or GIRE) model, was then used to calculate the Europa mission dose for an average and a 1-sigma worst-case situation. The prediction of the GIRE model is about a factor of 2 lower than the Divine model estimate over the range of 100 to 1000 mils (2.54 to 25.4 mm) of aluminum shielding, but exceeds the Divine model by about 50% for thicker shielding. The model, the steps leading to its creation, and relevant issues and concerns are discussed. While work remains to be done, the GIRE model clearly represents a significant step forward in the study of the jovian radiation environment, and it is a useful and valuable tool for estimating that environment for future space missions.

  15. Effects of fluoxetine on mast cell morphology and protease-1 expression in gastric antrum in a rat model of depression

    Institute of Scientific and Technical Information of China (English)

    Zhen-Hua Chen; Ling Xiao; Ji-Hong Chen; He-Shen Luo; Gao-Hua Wang; Yong-Lan Huang; Xiao-Ping Wang

    2008-01-01

    AIM: To investigate the effects of fluoxetine on depression-induced changes of mast cell morphology and protease-1 (rMCP-1) expression in rats.METHODS: A Sprague-Dawley rat model of chronic stress-induced depression was established. Fifty experimental rats were randomly divided into the following groups: normal control group, fluoxetine +normal control group, depressed model group, saline + depressed model group, and fluoxetine + depressed model group. Laser scanning confocal microscopy (LSCM) immunofluorecence and RT-PCR techniques were used to investigate rMCP-1 expression in gastric antrum. Mast cell morphology was observed under transmission electron microscopy. ANOVA was used for statistical analysis among groups.RESULTS: Morphologic observation indicated that depression induced mast cell proliferation, activation,and granule hyperplasia. Compared with the normal control group, the average immunofluorescence intensity of gastric antrum rMCP-1 significantly increased in depressed model group (37.4 4- 7.7 vs 24.5+ 5.6, P < 0.01) or saline + depressed model group (39.9 4- 5.0 vs 24.5 ± 5.6, P < 0.01), while there was no significant difference between fluoxetine + normal control group (23.1 4- 3.4) or fluoxetine + depressed model group (26.1 4- 3.6) and normal control group.The average level of rMCP-lmRNA of gastric antrum significantly increased in depressed model group (0.759 ± 0.357 vs 0.476 ± 0.029, P < 0.01) or saline + depressed model group (0.781 4- 0.451 vs 0.476 ±0.029, P < 0.01 ), while no significant difference was found between fluoxetine + normal control group (0.460 ± 0.027) or fluoxetine + depressed model group (0.488 ± 0.030) and normal control group. Fluoxetine showed partial inhibitive effects on mast cell ultrastructural alterations and de-regulated rMCP-1 expression in gastric antrum of the depressed rat model.CONCLUSION: Chronic stress can induce mast cell proliferation, activation, and granule hyperplasia in gastric antrum. Fluoxetine

  16. Lodenafil treatment in the monocrotaline model of pulmonary hypertension in rats

    OpenAIRE

    Polonio, Igor Bastos; Acencio, Milena Marques Pagliareli; Pazetti, Rogério; Almeida, Francine Maria de; Silva, Bárbara Soares da; Pereira, Karina Aparecida Bonifácio; Souza, Rogério

    2014-01-01

    We assessed the effects of lodenafil on hemodynamics and inflammation in the rat model of monocrotaline-induced pulmonary hypertension (PH). Thirty male Sprague-Dawley rats were randomly divided into three groups: control; monocrotaline (experimental model); and lodenafil (experimental model followed by lodenafil treatment, p.o., 5 mg/kg daily for 28 days) Mean pulmonary artery pressure (mPAP) was obtained by right heart catheterization. We investigated right ventricular hypertrophy (RVH) and...

  17. Simulating certain aspects of hypogravity: Effects on the mandibular incisors of suspended rats (PULEH model)

    Science.gov (United States)

    Simmons, D. J.; Winter, F.; Morey-Holton, E. R.

    1984-01-01

    The effect of a hypogravity simulating model on the rate of mandibular incisor formation, dentinogenesis and, amelogenesis in laboratory rats was studied. The model is the partial unloading by elevating the hindquarters. In this system, rat hindquarters are elevated 30 to 40 deg from the cage floors to completely unload the hindlimbs, but the animals are free to move about using their forelimbs. This model replicates the fluid sift changes which occur during the weightlessness of spaceflight and produces an osteopenia in the weight bearing skeletons. The histogenesis and/or mineralization rates of the mandibular incisor during the first 19d of PULEH in young growing rats are recorded.

  18. The Chemical Modeling of Electronic Materials and Interconnections

    Science.gov (United States)

    Kivilahti, J. K.

    2002-12-01

    Thermodynamic and kinetic modeling, together with careful experimental work, is of great help for developing new electronic materials such as lead-free solders, their compatible metallizations and diffusion-barrier layers, as well as joining and bonding processes for advanced electronics manufacturing. When combined, these modeling techniques lead to a rationalization of the trial-and-error methods employed in the electronics industry, limiting experimentation and, thus, reducing significantly time-to-market of new products. This modeling provides useful information on the stabilities of phases (microstructures), driving forces for chemical reactions, and growth rates of reaction products occurring in interconnections or thin-film structures during processing, testing, and in longterm use of electronic devices. This is especially important when manufacturing advanced lead-free electronics where solder joint volumes are decreasing while the number of dissimilar reactive materials is increasing markedly. Therefore, a new concept of local nominal composition was introduced and applied together with the relevant ternary and multicomponent phase diagrams to some solder/conductor systems.

  19. Comparative Proteomic Analysis of Two Uveitis Models in Lewis Rats.

    Science.gov (United States)

    Pepple, Kathryn L; Rotkis, Lauren; Wilson, Leslie; Sandt, Angela; Van Gelder, Russell N

    2015-12-01

    Inflammation generates changes in the protein constituents of the aqueous humor. Proteins that change in multiple models of uveitis may be good biomarkers of disease or targets for therapeutic intervention. The present study was conducted to identify differentially-expressed proteins in the inflamed aqueous humor. Two models of uveitis were induced in Lewis rats: experimental autoimmune uveitis (EAU) and primed mycobacterial uveitis (PMU). Differential gel electrophoresis was used to compare naïve and inflamed aqueous humor. Differentially-expressed proteins were separated by using 2-D gel electrophoresis and excised for identification with matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF). Expression of select proteins was verified by Western blot analysis in both the aqueous and vitreous. The inflamed aqueous from both models demonstrated an increase in total protein concentration when compared to naïve aqueous. Calprotectin, a heterodimer of S100A8 and S100A9, was increased in the aqueous in both PMU and EAU. In the vitreous, S100A8 and S100A9 were preferentially elevated in PMU. Apolipoprotein E was elevated in the aqueous of both uveitis models but was preferentially elevated in EAU. Beta-B2-crystallin levels decreased in the aqueous and vitreous of EAU but not PMU. The proinflammatory molecules S100A8 and S100A9 were elevated in both models of uveitis but may play a more significant role in PMU than EAU. The neuroprotective protein β-B2-crystallin was found to decline in EAU. Therapies to modulate these proteins in vivo may be good targets in the treatment of ocular inflammation.

  20. Heterogeneous stock rat: a unique animal model for mapping genes influencing bone fragility.

    Science.gov (United States)

    Alam, Imranul; Koller, Daniel L; Sun, Qiwei; Roeder, Ryan K; Cañete, Toni; Blázquez, Gloria; López-Aumatell, Regina; Martínez-Membrives, Esther; Vicens-Costa, Elia; Mont, Carme; Díaz, Sira; Tobeña, Adolf; Fernández-Teruel, Alberto; Whitley, Adam; Strid, Pernilla; Diez, Margarita; Johannesson, Martina; Flint, Jonathan; Econs, Michael J; Turner, Charles H; Foroud, Tatiana

    2011-05-01

    Previously, we demonstrated that skeletal mass, structure and biomechanical properties vary considerably among 11 different inbred rat strains. Subsequently, we performed quantitative trait loci (QTL) analysis in four inbred rat strains (F344, LEW, COP and DA) for different bone phenotypes and identified several candidate genes influencing various bone traits. The standard approach to narrowing QTL intervals down to a few candidate genes typically employs the generation of congenic lines, which is time consuming and often not successful. A potential alternative approach is to use a highly genetically informative animal model resource capable of delivering very high resolution gene mapping such as Heterogeneous stock (HS) rat. HS rat was derived from eight inbred progenitors: ACI/N, BN/SsN, BUF/N, F344/N, M520/N, MR/N, WKY/N and WN/N. The genetic recombination pattern generated across 50 generations in these rats has been shown to deliver ultra-high even gene-level resolution for complex genetic studies. The purpose of this study is to investigate the usefulness of the HS rat model for fine mapping and identification of genes underlying bone fragility phenotypes. We compared bone geometry, density and strength phenotypes at multiple skeletal sites in HS rats with those obtained from five of the eight progenitor inbred strains. In addition, we estimated the heritability for different bone phenotypes in these rats and employed principal component analysis to explore relationships among bone phenotypes in the HS rats. Our study demonstrates that significant variability exists for different skeletal phenotypes in HS rats compared with their inbred progenitors. In addition, we estimated high heritability for several bone phenotypes and biologically interpretable factors explaining significant overall variability, suggesting that the HS rat model could be a unique genetic resource for rapid and efficient discovery of the genetic determinants of bone fragility. Copyright

  1. Light, electron microscopic and immunohistochemical study of the effect of low-dose aspirin during the proestrus phase on rat endometrium in the preimplantation period.

    Science.gov (United States)

    Ateş, Utku; Baka, Meral; Turgut, Mehmet; Uyanikgil, Yiğit; Ulker, Sibel; Yilmaz, Ozlem; Tavmergen, Erol; Yurtseven, Mine

    2007-04-01

    To evaluate structural alterations in rat endometrium at preimplantation following treatment with aspirin beginning from proestrus by light microscopy, electron microscopy and immunohistochemical techniques. Twenty rats were divided into control (n = 10) and experimental (n = 10) groups. Experimental rats were treated with low-dose aspirin daily (2 mg/kg/day) during estrus, beginning from the proestrus phase, mated at end of cycle and treated with aspirin. Untreated pregnant rats were the control group. Rats in both groups were sacrificed at the 84th pregnancy hour; the uterus was rapidly removed and dissected free of surrounding adipose tissue. Uteri specimens from nonpregnant rats were transferred into fixative solution and processed for light, electron microscopic and immunohistochemical study. Light and electron microscopy of endometrium from control rats conformed to mid-diestrus phase; endometrial histology of the aspirin-treated group conformed to late diestrus phase. The endometrial layer was significantly thicker in the aspirin-treated group compared to the untreated control group (p <0.001). No significant difference was found in vessel number between groups. Staining with alphaV integrin was more dense in the aspirin-treated group. Based on histologic findings, we suggest low-dose aspirin has positive effects on preparing endometrium before implantation.

  2. Kinetic modelling of runaway electron avalanches in tokamak plasmas

    International Nuclear Information System (INIS)

    Nilsson, E; Peysson, Y; Saint-Laurent, F; Decker, J; Granetz, R S; Vlainic, M

    2015-01-01

    Runaway electrons can be generated in tokamak plasmas if the accelerating force from the toroidal electric field exceeds the collisional drag force owing to Coulomb collisions with the background plasma. In ITER, disruptions are expected to generate runaway electrons mainly through knock-on collisions (Hender et al 2007 Nucl. Fusion 47 S128–202), where enough momentum can be transferred from existing runaways to slow electrons to transport the latter beyond a critical momentum, setting off an avalanche of runaway electrons. Since knock-on runaways are usually scattered off with a significant perpendicular component of the momentum with respect to the local magnetic field direction, these particles are highly magnetized. Consequently, the momentum dynamics require a full 3D kinetic description, since these electrons are highly sensitive to the magnetic non-uniformity of a toroidal configuration. For this purpose, a bounce-averaged knock-on source term is derived. The generation of runaway electrons from the combined effect of Dreicer mechanism and knock-on collision process is studied with the code LUKE, a solver of the 3D linearized bounce-averaged relativistic electron Fokker–Planck equation (Decker and Peysson 2004 DKE: a fast numerical solver for the 3D drift kinetic equation Report EUR-CEA-FC-1736, Euratom-CEA), through the calculation of the response of the electron distribution function to a constant parallel electric field. The model, which has been successfully benchmarked against the standard Dreicer runaway theory now describes the runaway generation by knock-on collisions as proposed by Rosenbluth (Rosenbluth and Putvinski 1997 Nucl. Fusion 37 1355–62). This paper shows that the avalanche effect can be important even in non-disruptive scenarios. Runaway formation through knock-on collisions is found to be strongly reduced when taking place off the magnetic axis, since trapped electrons can not contribute to the runaway electron population. Finally

  3. Electron inertia effects for an electron fluid model by the applied-B ion diode

    Energy Technology Data Exchange (ETDEWEB)

    Gordeev, A V; Levchenko, S V [Kurchatov Institute, Moscow (Russian Federation). Nuclear Fusion Institute

    1997-12-31

    Numerical calculations within the framework of the one-dimensional vortex-like electron fluid model in applied-B ion diodes, taking account the electron inertia effects, are presented. The existence of the additional relation between the magnetic field and the electric potential offers an opportunity to reduce the ion diode problem to the system of the algebraic equations for the constants introduced. The ion current density in an ion diode is determined only by the magnetic flux cut out by the virtual cathode. As an illustration, the ion diode impedance for the KALIF device was calculated. (author). 2 figs., 6 refs.

  4. Test particle modeling of wave-induced energetic electron precipitation

    International Nuclear Information System (INIS)

    Chang, H.C.; Inan, U.S.

    1985-01-01

    A test particle computer model of the precipitation of radiation belt electrons is extended to compute the dynamic energy spectrum of transient electron fluxes induced by short-duration VLF wave packets traveling along the geomagnetic field lines. The model is adapted to estimate the count rate and associated spectrum of precipitated electrons that would be observed by satellite-based particle detectors with given geometric factor and orientation with respect to the magnetic field. A constant-frequency wave pulse and a lightning-induced whistler wave packet are used as examples of the stimulating wave signals. The effects of asymmetry of particle mirror heights in the two hemispheres and the atmospheric backscatter of loss cone particles on the computed precipitated fluxes are discussed

  5. Model for voluntary wine and alcohol consumption in rats.

    Science.gov (United States)

    Arola, L; Roig, R; Cascón, E; Brunet, M J; Fornós, N; Sabaté, M; Raga, X; Batista, J; Salvadó, M J; Bladé, C

    1997-08-01

    It has been suggested that moderate consumption of ethanol and wine has a protective effect on human health. Animal models used to date for alcohol consumption can not mimic real situations in humans because the consumption is forced and/or excessive. The present study proposes to determine the effects of a voluntary and ad lib consumption model more similar to that of human behavior. Male Wistar rats had free access to either standard diet and water or the same diet plus red wine, sweet wine, or a solution equivalent to red wine (13.5% ethanol) or to sweet wine (20% ethanol + 130 g/L sucrose) for 30 days or 6 months. Daily wine consumption was 15.8 +/- 0.9 and 2.0 +/- 0.2 ml/day for sweet and red wines, respectively. The consumption of each of the alcoholic solutions was similar to that of the wine they were simulating. Drinking wine or ethanol did not affect food and water intakes or growth rate. Plasma metabolites were not substantially affected by consumption of wine or ethanol. Although moderate and high wine consumption did not change the activity of plasma marker enzymes of tissue damage, the consumption of the 2 alcoholic solutions caused a long-term increase in the activity of aspartate aminotransferase. It seems that wine consumption protects the organism from hepatic lesions induced by ethanol alone.

  6. Mathematical Model of Ammonia Handling in the Rat Renal Medulla

    Science.gov (United States)

    Noiret, Lorette; Baigent, Stephen; Jalan, Rajiv; Thomas, S. Randall

    2015-01-01

    The kidney is one of the main organs that produces ammonia and release it into the circulation. Under normal conditions, between 30 and 50% of the ammonia produced in the kidney is excreted in the urine, the rest being absorbed into the systemic circulation via the renal vein. In acidosis and in some pathological conditions, the proportion of urinary excretion can increase to 70% of the ammonia produced in the kidney. Mechanisms regulating the balance between urinary excretion and renal vein release are not fully understood. We developed a mathematical model that reflects current thinking about renal ammonia handling in order to investigate the role of each tubular segment and identify some of the components which might control this balance. The model treats the movements of water, sodium chloride, urea, NH3 and NH4+, and non-reabsorbable solute in an idealized renal medulla of the rat at steady state. A parameter study was performed to identify the transport parameters and microenvironmental conditions that most affect the rate of urinary ammonia excretion. Our results suggest that urinary ammonia excretion is mainly determined by those parameters that affect ammonia recycling in the loops of Henle. In particular, our results suggest a critical role for interstitial pH in the outer medulla and for luminal pH along the inner medullary collecting ducts. PMID:26280830

  7. Induced hypothermia is protective in a rat model of pneumococcal pneumonia associated with increased adenosine triphosphate availability and turnover

    NARCIS (Netherlands)

    Beurskens, Charlotte J. P.; Aslami, Hamid; Kuipers, Maria T.; Horn, Janneke; Vroom, Margreeth B.; van Kuilenburg, André B. P.; Roelofs, Joris J. T. H.; Schultz, Marcus J.; Juffermans, Nicole P.

    2012-01-01

    Objective: To determine the effect of induced hypothermia on bacterial growth, lung injury, and mitochondrial function in a rat model of pneumococcal pneumosepsis. Design: Animal study. Setting: University research laboratory. Subjects: Male Sprague-Dawley rats. Interventions: Subjects were

  8. The Influence of a High Salt Diet on a Rat Model of Isoproterenol-Induced Heart Failure

    Science.gov (United States)

    Rat models of heart failure (HF) show varied pathology and time to disease outcome, dependent on induction method. We found that subchronic (4 weeks) isoproterenol (ISO) infusion exacerbated cardiomyopathy in Spontaneously Hypertensive Heart Failure (SHHF) rats. Others have shown...

  9. Electronic Processes at Organic−Organic Interfaces: Insight from Modeling and Implications for Opto-electronic Devices †

    KAUST Repository

    Beljonne, David; Cornil, Jérôme; Muccioli, Luca; Zannoni, Claudio; Brédas, Jean-Luc; Castet, Frédéric

    2011-01-01

    We report on the recent progress achieved in modeling the electronic processes that take place at interfaces between π-conjugated materials in organic opto-electronic devices. First, we provide a critical overview of the current computational

  10. A Novel Newborn Rat Kernicterus Model Created by Injecting a Bilirubin Solution into the Cisterna Magna

    Science.gov (United States)

    Song, Sijie; Hu, Ying; Gu, Xianfang; Si, Feifei; Hua, Ziyu

    2014-01-01

    Background Kernicterus still occurs around the world; however, the mechanism of bilirubin neurotoxicity remains unclear, and effective treatment strategies are lacking. To solve these problems, several kernicterus (or acute bilirubin encephalopathy) animal models have been established, but these models are difficult and expensive. Therefore, the present study was performed to establish a novel kernicterus model that is simple and affordable by injecting unconjugated bilirubin solution into the cisterna magna (CM) of ordinary newborn Sprague-Dawley (SD) rats. Methods On postnatal day 5, SD rat pups were randomly divided into bilirubin and control groups. Then, either bilirubin solution or ddH2O (pH = 8.5) was injected into the CM at 10 µg/g (bodyweight). For model characterization, neurobehavioral outcomes were observed, mortality was calculated, and bodyweight was recorded after bilirubin injection and weaning. Apoptosis in the hippocampus was detected by H&E staining, TUNEL, flow cytometry and Western blotting. When the rats were 28 days old, learning and memory ability were evaluated using the Morris water maze test. Results The bilirubin-treated rats showed apparently abnormal neurological manifestations, such as clenched fists, opisthotonos and torsion spasms. Bodyweight gain in the bilirubin-treated rats was significantly lower than that in the controls (Pbilirubin-treated rats were both dramatically higher than those of the controls (P = 0.004 and 0.017, respectively). Apoptosis and necrosis in the hippocampal nerve cells in the bilirubin-treated rats were observed. The bilirubin-treated rats performed worse than the controls on the Morris water maze test. Conclusion By injecting bilirubin into the CM, we successfully created a new kernicterus model using ordinary SD rats; the model mimics both the acute clinical manifestations and the chronic sequelae. In particular, CM injection is easy to perform; thus, more stable models for follow-up study are

  11. Lemon juice has protective activity in a rat urolithiasis model

    Directory of Open Access Journals (Sweden)

    Oussama Abdelkhalek

    2007-10-01

    Full Text Available Abstract Background The use of herbal medicines (medicinal plants or phytotherapy has recently gained popularity in Europe and the United States. Nevertheless the exact mechanism of the preventive effects of these products is still far to be clearly established, being its knowledge necessary to successfully apply these therapies to avoid stone formation. Methods The effect of oral lemon juice administration on calcium oxalate urolithiasis was studied in male Wistar rats. Rats were rendered nephrolithic by providing drinking water containing 0.75% ethylene glycol [v/v] (EG and 2% ammonium chloride [w/v] (AC for 10 days. In addition to EG/AC treatment, three groups of rats were also gavage-administered solutions containing 100%, 75% or 50% lemon juice [v/v] (6 μl solution/g body weight. Positive control rats were treated with EG/AC but not lemon juice. Negative control rats were provided with normal drinking water, and were administered normal water by gavage. Each group contained 6 rats. After 10 days, serum samples were collected for analysis, the left kidney was removed and assessed for calcium levels using flame spectroscopy, and the right kidney was sectioned for histopathological analysis using light microscopy. Results Analysis showed that the rats treated with EG/AC alone had higher amounts of calcium in the kidneys compared to negative control rats. This EG/AC-induced increase in kidney calcium levels was inhibited by the administration of lemon juice. Histology showed that rats treated with EG/AC alone had large deposits of calcium oxalate crystals in all parts of the kidney, and that such deposits were not present in rats also treated with either 100% or 75% lemon juice. Conclusion These data suggest that lemon juice has a protective activity against urolithiasis.

  12. Aging aggravates long-term renal ischemia-reperfusion injury in a rat model.

    Science.gov (United States)

    Xu, Xianlin; Fan, Min; He, Xiaozhou; Liu, Jipu; Qin, Jiandi; Ye, Jianan

    2014-03-01

    Ischemia-reperfusion injury (IRI) has been considered as the major cause of acute kidney injury and can result in poor long-term graft function. Functional recovery after IRI is impaired in the elderly. In the present study, we aimed to compare kidney morphology, function, oxidative stress, inflammation, and development of renal fibrosis in young and aged rats after renal IRI. Rat models of warm renal IRI were established by clamping left pedicles for 45 min after right nephrectomy, then the clamp was removed, and kidneys were reperfused for up to 12 wk. Biochemical and histologic renal damage were assessed at 12 wk after reperfusion. The immunohistochemical staining of monocyte macrophage antigen-1 (ED-1) and transforming growth factor beta 1 (TGF-β1) and messenger RNA level of TGF-β1 in the kidney were analyzed. Renal IRI caused significant increases of malondialdehyde and 8-hydroxydeoxyguanosine levels and a decrease of superoxide dismutase activity in young and aged IRI rats; however, these changes were more obvious in the aged rats. IRI resulted in severe inflammation and tubulointerstitial fibrosis with decreased creatinine (Cr) clearance and increased histologic damage in aged rats compared with young rats. Moreover, we measured the ratio of Cr clearance between young and aged IRI rats. It demonstrated that aged IRI rats did have poor Cr clearance compared with the young IRI rats. ED-1 and TGF-β1 expression levels in the kidney were significantly higher in aged rats than in young rats after IRI. Aged rats are more susceptible to IRI-induced renal failure, which may associate with the increased oxidative stress, increased histologic damage, and increased inflammation and tubulointerstitial fibrosis. Targeting oxidative stress and inflammatory response should improve the kidney recovery after IRI. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Test of models for electron transport in laser produced plasmas

    International Nuclear Information System (INIS)

    Colombant, D.G.; Manheimer, W.M.; Busquet, M.

    2005-01-01

    This paper examines five different models of electron thermal transport in laser produced spherical implosions. These are classical, classical with a flux limit f, delocalization, beam deposition model, and Fokker-Planck solutions. In small targets, the results are strongly dependent on f for flux limit models, with small f's generating very steep temperature gradients. Delocalization models are characterized by large preheat in the center of the target. The beam deposition model agrees reasonably well with the Fokker-Planck simulation results. For large, high gain fusion targets, the delocalization model shows the gain substantially reduced by the preheat. However, flux limitation models show gain largely independent of f, with the beam deposition model also showing the same high gain

  14. Modeling of humidity-related reliability in enclosures with electronics

    DEFF Research Database (Denmark)

    Hygum, Morten Arnfeldt; Popok, Vladimir

    2015-01-01

    Reliability of electronics that operate outdoor is strongly affected by environmental factors such as temperature and humidity. Fluctuations of these parameters can lead to water condensation inside enclosures. Therefore, modelling of humidity distribution in a container with air and freely exposed...

  15. Towards model-based testing of electronic funds transfer systems

    NARCIS (Netherlands)

    Asaadi, H.R.; Khosravi, R.; Mousavi, M.R.; Noroozi, N.; Arbab, F.; Sirjani, M.

    2012-01-01

    We report on our first experience with applying model-based testing techniques to an operational Electronic Funds Transfer (EFT) switch. The goal is to test the conformance of the EFT switch to the standard flows described by the ISO 8583 standard. To this end, we first make a formalization of the

  16. Towards model-based testing of electronic funds transfer systems

    NARCIS (Netherlands)

    Asaadi, H.R.; Khosravi, R.; Mousavi, M.R.; Noroozi, N.

    2010-01-01

    We report on our first experience with applying model-based testing techniques to an operational Electronic Funds Transfer (EFT) switch. The goal is to test the conformance of the EFT switch to the standard flows described by the ISO 8583 standard. To this end, we first make a formalization of the

  17. A multi water bag model of drift kinetic electron plasma

    International Nuclear Information System (INIS)

    Morel, P.; Dreydemy Ghiro, F.; Berionni, V.; Gurcan, O.D.; Coulette, D.; Besse, N.

    2014-01-01

    A Multi Water Bag model is proposed for describing drift kinetic plasmas in a magnetized cylindrical geometry, relevant for various experimental devices, solar wind modeling... The Multi Water Bag (MWB) model is adapted to the description of a plasma with kinetic electrons as well as an arbitrary number of kinetic ions. This allows to describe the kinetic dynamics of the electrons, making possible the study of electron temperature gradient (ETG) modes, in addition to the effects of non adiabatic electrons on the ion temperature gradient (ITG) modes, that are of prime importance in the magnetized plasmas micro-turbulence [X. Garbet, Y. Idomura, L. Villard, T.H. Watanabe, Nucl. Fusion 50, 043002 (2010); J.A. Krommes, Ann. Rev. Fluid Mech. 44, 175 (2012)]. The MWB model is shown to link kinetic and fluid descriptions, depending on the number of bags considered. Linear stability of the ETG modes is presented and compared to the existing results regarding cylindrical ITG modes [P. Morel, E. Gravier, N. Besse, R. Klein, A. Ghizzo, P. Bertrand, W. Garbet, Ph. Ghendrih, V. Grandgirard, Y. Sarazin, Phys. Plasmas 14, 112109 (2007)]. (authors)

  18. Three phase carbon EOS model with electronic excitation

    International Nuclear Information System (INIS)

    van Thiel, M.; Ree, F.H.; Grover, R.

    1987-07-01

    A simple and rapid way for computing EOS data of multiphase solids with a liquid phase is described with emphasis on carbon. The method uses a scaling model for the liquid phase and includes a provision for electronic effects. The free energy minimum determines the stable phase

  19. Toward a generic model of trust for electronic commerce

    NARCIS (Netherlands)

    Tan, YH; Thoen, W

    2000-01-01

    The authors present a generic model of trust for electronic commerce consisting of two basic components, party trust and control trust, based on the concept that trust in a transaction with another party combines trust in the other parry and trust in the control mechanisms that ensure the successful

  20. Classical model of the Dirac electron in curved space

    International Nuclear Information System (INIS)

    Barut, A.O.; Pavsic, M.

    1987-01-01

    The action for the classical model of the electron exhibiting Zitterbewegung is generalized to curved space by introducing a spin connection. The dynamical equations and the symplectic structure are given for several different choices of the variables. In particular, we obtain the equation of motion for spin and compare it with the Papapetrou equation. (author)

  1. Technical Communicator: A New Model for the Electronic Resources Librarian?

    Science.gov (United States)

    Hulseberg, Anna

    2016-01-01

    This article explores whether technical communicator is a useful model for electronic resources (ER) librarians. The fields of ER librarianship and technical communication (TC) originated and continue to develop in relation to evolving technologies. A review of the literature reveals four common themes for ER librarianship and TC. While the…

  2. Study on the damage effect of 131I-iodinated oil internal radiation in SMMC-7721 hepatoma model in rat

    International Nuclear Information System (INIS)

    Wu Shuyan; Zhang Xuguang; Wang Xiangying; Li Su'an; Mao Dihua

    2004-01-01

    Objective: To investigate the damage effect of 131 I-iodinated oil internal radiation in hepatoma. Methods: SMMC-7721 rat hepatoma model was used to evaluate the damage of 131 I-iodinated oil internal radiation in carcinoma. 131 I-iodinated oil was injected sector-shapely into tumor model of SMMC-7721 hepatoma with arc-needle, matched with routine straight-needle injection. Tumor damage induced by 131 I-iodinated oil intralesion radiation in the carcinoma models are recorded through survival time, weight of rat, local carcinoma, pathology, electron microscopy. Results: Arc-needle injection 131 I-iodinated oil in SMMC-7721 hepatoma at subcutis could increase rat's survival time, the body weight kept less descent, the lumps necrosed wholly. Pathology and ultrastructure detection revealed cell necrosis and collapse, sever nuclear damage was observed in the death cells. The early characteristics of necrosis such as margination of heterochromatin was also found in some tumor cells. Besides, well differentiated tumor cells, degenerative tumor cells and some lymphocytes were seen. Conclusion: Arc-needle injection 131 I-iodinated oil step-by step sector-shapely into tumor is a better method and necrosis is the major effect of 131 I-iodinated oil internal radiation in carcinoma at the level of treated dosage

  3. Tissue responses to hexyl 5-aminolevulinate-induced photodynamic treatment in syngeneic orthotopic rat bladder cancer model: possible pathways of action

    Science.gov (United States)

    Arum, Carl-Jørgen; Gederaas, Odrun A.; Larsen, Eivind L. P.; Randeberg, Lise L.; Hjelde, Astrid; Krokan, Hans E.; Svaasand, Lars O.; Chen, Duan; Zhao, Chun-Mei

    2011-02-01

    Orthotopic bladder cancer model in rats mimics human bladder cancer with respect to urothelial tumorigenesis and progression. Utilizing this model at pT1 (superficial stage), we analyze the tissue responses to hexyl 5-aminolevulinate-induced photodynamic therapy (HAL-PDT). In comparison to untreated rats, HAL-PDT causes little change in tumor-free rat bladder but induces inflammatory changes with increased lymphocytes and mononuclear cell infiltration in rat bladders with tumor. Immunohistochemistry reveals that HAL-PDT is without effect on proliferating cell nuclear antigen expression within the tumor and increases caspase-3 expression in both normal urothelium and the tumor. Transmission electron microscopy reveals severe mitochondrial damage, formations of apoptotic bodies, vacuoles, and lipofuscin bodies, but no microvillus-formed niches in HAL-PDT-treated bladder cancer rats. Bioinformatics analysis of the gene expression profile indicates an activation of T-cell receptor signaling pathway in bladder cancer rats without PDT. HAL-PDT increases the expression of CD3 and CD45RA in the tumor (determined by immunohistochemistry). We suggest that pathways of action of HAL-PDT may include, at least, activations of mitochondrial apoptosis and autophagy, breakdown of cancer stem cell niches, and importantly, enhancement of T-cell activation.

  4. Alterations of the tunica vasculosa lentis in the rat model of retinopathy of prematurity.

    Science.gov (United States)

    Favazza, Tara L; Tanimoto, Naoyuki; Munro, Robert J; Beck, Susanne C; Garcia Garrido, Marina; Seide, Christina; Sothilingam, Vithiyanjali; Hansen, Ronald M; Fulton, Anne B; Seeliger, Mathias W; Akula, James D

    2013-08-01

    To study the relationship between retinal and tunica vasculosa lentis (TVL) disease in retinopathy of prematurity (ROP). Although the clinical hallmark of ROP is abnormal retinal blood vessels, the vessels of the anterior segment, including the TVL, are also altered. ROP was induced in Long-Evans pigmented and Sprague Dawley albino rats; room-air-reared (RAR) rats served as controls. Then, fluorescein angiographic images of the TVL and retinal vessels were serially obtained with a scanning laser ophthalmoscope near the height of retinal vascular disease, ~20 days of age, and again at 30 and 64 days of age. Additionally, electroretinograms (ERGs) were obtained prior to the first imaging session. The TVL images were analyzed for percent coverage of the posterior lens. The tortuosity of the retinal arterioles was determined using Retinal Image multiScale Analysis (Gelman et al. in Invest Ophthalmol Vis Sci 46:4734-4738, 2005). In the youngest ROP rats, the TVL was dense, while in RAR rats, it was relatively sparse. By 30 days, the TVL in RAR rats had almost fully regressed, while in ROP rats, it was still pronounced. By the final test age, the TVL had completely regressed in both ROP and RAR rats. In parallel, the tortuous retinal arterioles in ROP rats resolved with increasing age. ERG components indicating postreceptoral dysfunction, the b-wave, and oscillatory potentials were attenuated in ROP rats. These findings underscore the retinal vascular abnormalities and, for the first time, show abnormal anterior segment vasculature in the rat model of ROP. There is delayed regression of the TVL in the rat model of ROP. This demonstrates that ROP is a disease of the whole eye.

  5. Electron Flux Models for Different Energies at Geostationary Orbit

    Science.gov (United States)

    Boynton, R. J.; Balikhin, M. A.; Sibeck, D. G.; Walker, S. N.; Billings, S. A.; Ganushkina, N.

    2016-01-01

    Forecast models were derived for energetic electrons at all energy ranges sampled by the third-generation Geostationary Operational Environmental Satellites (GOES). These models were based on Multi-Input Single-Output Nonlinear Autoregressive Moving Average with Exogenous inputs methodologies. The model inputs include the solar wind velocity, density and pressure, the fraction of time that the interplanetary magnetic field (IMF) was southward, the IMF contribution of a solar wind-magnetosphere coupling function proposed by Boynton et al. (2011b), and the Dst index. As such, this study has deduced five new 1 h resolution models for the low-energy electrons measured by GOES (30-50 keV, 50-100 keV, 100-200 keV, 200-350 keV, and 350-600 keV) and extended the existing >800 keV and >2 MeV Geostationary Earth Orbit electron fluxes models to forecast at a 1 h resolution. All of these models were shown to provide accurate forecasts, with prediction efficiencies ranging between 66.9% and 82.3%.

  6. Significance of matrix diagonalization in modelling inelastic electron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Z. [University of Ulm, Ulm 89081 (Germany); Hambach, R. [University of Ulm, Ulm 89081 (Germany); University of Jena, Jena 07743 (Germany); Kaiser, U.; Rose, H. [University of Ulm, Ulm 89081 (Germany)

    2017-04-15

    Electron scattering is always applied as one of the routines to investigate nanostructures. Nowadays the development of hardware offers more and more prospect for this technique. For example imaging nanostructures with inelastic scattered electrons may allow to produce component-sensitive images with atomic resolution. Modelling inelastic electron scattering is therefore essential for interpreting these images. The main obstacle to study inelastic scattering problem is its complexity. During inelastic scattering, incident electrons entangle with objects, and the description of this process involves a multidimensional array. Since the simulation usually involves fourdimensional Fourier transforms, the computation is highly inefficient. In this work we have offered one solution to handle the multidimensional problem. By transforming a high dimensional array into twodimensional array, we are able to perform matrix diagonalization and approximate the original multidimensional array with its twodimensional eigenvectors. Our procedure reduces the complicated multidimensional problem to a twodimensional problem. In addition, it minimizes the number of twodimensional problems. This method is very useful for studying multiple inelastic scattering. - Highlights: • 4D problems are involved in modelling inelastic electron scattering. • By means of matrix diagonalization, the 4D problems can be simplified as 2D problems. • The number of 2D problems is minimized by using this approach.

  7. Spatial modeling of rat bites and prediction of rat infestation in Peshawar valley using binomial kriging with logistic regression.

    Science.gov (United States)

    Ali, Asad; Zaidi, Farrah; Fatima, Syeda Hira; Adnan, Muhammad; Ullah, Saleem

    2018-03-24

    In this study, we propose to develop a geostatistical computational framework to model the distribution of rat bite infestation of epidemic proportion in Peshawar valley, Pakistan. Two species Rattus norvegicus and Rattus rattus are suspected to spread the infestation. The framework combines strengths of maximum entropy algorithm and binomial kriging with logistic regression to spatially model the distribution of infestation and to determine the individual role of environmental predictors in modeling the distribution trends. Our results demonstrate the significance of a number of social and environmental factors in rat infestations such as (I) high human population density; (II) greater dispersal ability of rodents due to the availability of better connectivity routes such as roads, and (III) temperature and precipitation influencing rodent fecundity and life cycle.

  8. Improvement of insulin secretion in rat models of diabetes after ACEI/ARB therapy

    International Nuclear Information System (INIS)

    Tian Jingyan; Li Fengying; Liu Yun; Long Hongmei; Li Weiyi; Wang Xiao; Zhang Hongli; Li Guo; Luo Min

    2009-01-01

    Objective To study the effect of ACEI/ARB therapy on the secretion of insulin and glucagon as well as serum lipid peroxidation marker 8-iso PGF-2α levels in streptozoticin (STZ) induced diabetic rat models.Methods Twenty-four rat models of STZ induced diabetes were prepared (random blood sugar>16.7 mmol/L). Of which, 8 models were fed enalaprial 5mg/kg/d, 8 models were fed losartan 10μg/kg/d and 8 models left unterated. Fasting serum insulin,glucagon (with RIA) and 8-iso PGF-2α (with ELISA) levels were measured in these models and 8 control rats three weeks later. Intravenous glucose tolerance test (IVGTT) were performed in 12 rats (3 animals in each group) six weeks later. Results: Serum levels of insulin in the treated models were higher than those in the non-treated models but without significance (P>0.05). Serum levels of glucagon and 8-iso PGF-2α levels in the treated models were significantly lower than those in the non-treated models (P 6 x ) in the treated models. Conclusion: ACEI/ARB treatment could improve the secretion of insulin in rat models of diabetes, which might be beneficial for controlling the progression of the disease. This phenomenon is consistent with the result of clinical study. (authors)

  9. The JCR:LA-cp rat: a novel rodent model of cystic medial necrosis.

    Science.gov (United States)

    Pung, Yuh Fen; Chilian, William M; Bennett, Martin R; Figg, Nichola; Kamarulzaman, Mohd Hamzah

    2017-03-01

    Although there are multiple rodent models of the metabolic syndrome, very few develop vascular complications. In contrast, the JCR:LA-cp rat develops both metabolic syndrome and early atherosclerosis in predisposed areas. However, the pathology of the normal vessel wall has not been described. We examined JCR:LA control (+/+) or cp/cp rats fed normal chow diet for 6 or 18 mo. JCR:LA-cp rats developed multiple features of advanced cystic medial necrosis including "cysts," increased collagen formation and proteoglycan deposition around cysts, apoptosis of vascular smooth muscle cells, and spotty medial calcification. These appearances began within 6 mo and were extensive by 18 mo. JCR:LA-cp rats had reduced medial cellularity, increased medial thickness, and vessel hypoxia that was most marked in the adventitia. In conclusion, the normal chow-fed JCR:LA-cp rat represents a novel rodent model of cystic medial necrosis, associated with multiple metabolic abnormalities, vascular smooth muscle cell apoptosis, and vessel hypoxia. NEW & NOTEWORTHY Triggers for cystic medial necrosis (CMN) have been difficult to study due to lack of animal models to recapitulate the pathologies seen in humans. Our study is the first description of CMN in the rat. Thus the JCR:LA-cp rat represents a useful model to investigate the underlying molecular changes leading to the development of CMN. Copyright © 2017 the American Physiological Society.

  10. Additive effects of dietary glycotoxins and androgen excess on the kidney of a female rat model

    Directory of Open Access Journals (Sweden)

    Sotiria Palimeri

    2016-06-01

    Conclusions: The above mentioned data suggest that dietary glycotoxins, in combination with increased androgen exposure, exert a more profound negative impact on the kidney of an androgenized female rat model that mimics the metabolic characteristics of polycystic ovary syndrome.

  11. Band electron spectrum and thermodynamic properties of the pseudospin-electron model with tunneling splitting of levels

    Directory of Open Access Journals (Sweden)

    O.Ya.Farenyuk

    2006-01-01

    Full Text Available The pseudospin-electron model with tunneling splitting of levels is considered. Generalization of dynamic mean-field method for systems with correlated hopping was applied to the investigation of the model. Electron spectra, electron concentrations, average values of pseudospins and grand canonical potential were calculated within the alloy-analogy approximation. Electron spectrum and dependencies of the electron concentrations on chemical potential were obtained. It was shown that in the alloy-analogy approximation, the model possesses the first order phase transition to ferromagnetic state with the change of chemical potential and the second order phase transition with the change of temperature.

  12. Many-electron model for multiple ionization in atomic collisions

    International Nuclear Information System (INIS)

    Archubi, C D; Montanari, C C; Miraglia, J E

    2007-01-01

    We have developed a many-electron model for multiple ionization of heavy atoms bombarded by bare ions. It is based on the transport equation for an ion in an inhomogeneous electronic density. Ionization probabilities are obtained by employing the shell-to-shell local plasma approximation with the Levine and Louie dielectric function to take into account the binding energy of each shell. Post-collisional contributions due to Auger-like processes are taken into account by employing recent photoemission data. Results for single-to-quadruple ionization of Ne, Ar, Kr and Xe by protons are presented showing a very good agreement with experimental data

  13. Many-electron model for multiple ionization in atomic collisions

    Energy Technology Data Exchange (ETDEWEB)

    Archubi, C D [Instituto de AstronomIa y Fisica del Espacio, Casilla de Correo 67, Sucursal 28 (C1428EGA) Buenos Aires (Argentina); Montanari, C C [Instituto de AstronomIa y Fisica del Espacio, Casilla de Correo 67, Sucursal 28 (C1428EGA) Buenos Aires (Argentina); Miraglia, J E [Instituto de AstronomIa y Fisica del Espacio, Casilla de Correo 67, Sucursal 28 (C1428EGA) Buenos Aires (Argentina)

    2007-03-14

    We have developed a many-electron model for multiple ionization of heavy atoms bombarded by bare ions. It is based on the transport equation for an ion in an inhomogeneous electronic density. Ionization probabilities are obtained by employing the shell-to-shell local plasma approximation with the Levine and Louie dielectric function to take into account the binding energy of each shell. Post-collisional contributions due to Auger-like processes are taken into account by employing recent photoemission data. Results for single-to-quadruple ionization of Ne, Ar, Kr and Xe by protons are presented showing a very good agreement with experimental data.

  14. Magnetic Electron Filtering by Fluid Models for the PEGASES Thruster

    Science.gov (United States)

    Leray, Gary; Chabert, Pascal; Lichtenberg, Allan; Lieberman, Michael

    2009-10-01

    The PEGASES thruster produces thrust by creating positive and negative ions, which are then accelerated. To accelerate both type of ions, electrons need to be filtered, which is achieved by applying a static magnetic field strong enough to magnetize the electrons but not the ions. A 1D fluid model with three species (electrons, positive and negative ions) and an analytical model are proposed to understand this process for an oxygen plasma with p = 10 mTorr and B0 = 300 G [1]. The resulting ion-ion plasma formation in the transverse direction (perpendicular to the magnetic field) is demonstrated. It is shown that an additional electron/positive ion loss term is required. The solutions are evaluated for two main parameters: the ionizing fraction at the plasma center (x = 0), ne0/ng, and the electronegativity ratio at the center, α0=nn0/ne0. The effect of geometry and magnetic field amplitude are also discussed. [4pt] [1] Leray G, Chabert P, Lichtenberg A J and Lieberman M A, J. Phys. D: Appl. Phys., Plasma Modelling Cluster issue, to appear (2009)

  15. Structure-Activity Relationship Models for Rat Carcinogenesis and Assessing the Role Mutagens Play in Model Predictivity

    Science.gov (United States)

    Carrasquer, C. Alex; Batey, Kaylind; Qamar, Shahid; Cunningham, Albert R.; Cunningham, Suzanne L.

    2016-01-01

    We previously demonstrated that fragment based cat-SAR carcinogenesis models consisting solely of mutagenic or non-mutagenic carcinogens varied greatly in terms of their predictive accuracy. This led us to investigate how well the rat cancer cat-SAR model predicted mutagens and non-mutagens in their learning set. Four rat cancer cat-SAR models were developed: Complete Rat, Transgender Rat, Male Rat, and Female Rat, with leave-one-out (LOO) validation concordance values of 69%, 74%, 67%, and 73%, respectively. The mutagenic carcinogens produced concordance values in the range of 69–76% as compared to only 47–53% for non-mutagenic carcinogens. As a surrogate for mutagenicity comparisons between single site and multiple site carcinogen SAR models was analyzed. The LOO concordance values for models consisting of 1-site, 2-site, and 4+-site carcinogens were 66%, 71%, and 79%, respectively. As expected, the proportion of mutagens to non-mutagens also increased, rising from 54% for 1-site to 80% for 4+-site carcinogens. This study demonstrates that mutagenic chemicals, in both SAR learning sets and test sets, are influential in assessing model accuracy. This suggests that SAR models for carcinogens may require a two-step process in which mutagenicity is first determined before carcinogenicity can be accurately predicted. PMID:24697549

  16. A novel experimental model of erectile dysfunction in rats with heart failure using volume overload.

    Science.gov (United States)

    Silva, Fábio Henrique; Veiga, Frederico José Reis; Mora, Aline Gonçalves; Heck, Rodrigo Sader; De Oliveira, Caroline Candida; Gambero, Alessandra; Franco-Penteado, Carla Fernanda; Antunes, Edson; Gardner, Jason D; Priviero, Fernanda Bruschi Marinho; Claudino, Mário Angelo

    2017-01-01

    Patients with heart failure (HF) display erectile dysfunction (ED). However, the pathophysiology of ED during HF remains poorly investigated. This study aimed to characterize the aortocaval fistula (ACF) rat model associated with HF as a novel experimental model of ED. We have undertaken molecular and functional studies to evaluate the alterations of the nitric oxide (NO) pathway, autonomic nervous system and oxidative stress in the penis. Male rats were submitted to ACF for HF induction. Intracavernosal pressure in anesthetized rats was evaluated. Concentration-response curves to contractile (phenylephrine) and relaxant agents (sodium nitroprusside; SNP), as well as to electrical field stimulation (EFS), were obtained in the cavernosal smooth muscle (CSM) strips from sham and HF rats. Protein expression of endothelial NO synthase (eNOS) and neuronal NO synthase (nNOS) and phosphodiestarese-5 in CSM were evaluated, as well as NOX2 (gp91phox) and superoxide dismutase (SOD) mRNA expression. SOD activity and thiobarbituric acid reactive substances (TBARs) were also performed in plasma. HF rats display erectile dysfunction represented by decreased ICP responses compared to sham rats. The neurogenic contractile responses elicited by EFS were greater in CSM from the HF group. Likewise, phenylephrine-induced contractions were greater in CSM from HF rats. Nitrergic response induced by EFS were decreased in the cavernosal tissue, along with lower eNOS, nNOS and phosphodiestarese-5 protein expressions. An increase of NOX2 and SOD mRNA expression in CSM and plasma TBARs of HF group were detected. Plasma SOD activity was decreased in HF rats. ED in HF rats is associated with decreased NO bioavailability in erectile tissue due to eNOS/nNOS dowregulation and NOX2 upregulation, as well as hypercontractility of the penis. This rat model of ACF could be a useful tool to evaluate the molecular alterations of ED associated with HF.

  17. WNIN/GR-Ob - an insulin-resistant obese rat model from inbred WNIN strain.

    Science.gov (United States)

    Harishankar, N; Vajreswari, A; Giridharan, N V

    2011-09-01

    WNIN/GR-Ob is a mutant obese rat strain with impaired glucose tolerance (IGT) developed at the National Institute of Nutrition (NIN), Hyderabad, India, from the existing 80 year old Wistar rat (WNIN) stock colony. The data presented here pertain to its obese nature along with IGT trait as evidenced by physical, physiological and biochemical parameters. The study also explains its existence, in three phenotypes: homozygous lean (+/+), heterozygous carrier (+/-) and homozygous obese (-/-). Thirty animals (15 males and 15 females) from each phenotype (+/+, +/-, -/-) and 24 lean and obese (6 males and 6 females) rats were taken for growth and food intake studies respectively. Twelve adult rats from each phenotype were taken for body composition measurement by total body electrical conductivity (TOBEC); 12 rats of both genders from each phenotype at different ages were taken for clinical chemistry parameters. Physiological indices of insulin resistance were calculated according to the homeostasis model assessment for insulin resistance (HOMA-IR) and also by studying U¹⁴C 2-deoxy glucose uptake (2DG). WNINGR-Ob mutants had high growth, hyperphagia, polydipsia, polyurea, glycosuria, and significantly lower lean body mass, higher fat mass as compared with carrier and lean rats. These mutants, at 50 days of age displayed abnormal response to glucose load (IGT), hyperinsulinaemia, hypertriglyceridaemia, hypercholesterolaemia and hyperleptinaemia. Basal and insulin-stimulated glucose uptakes by diaphragm were significantly decreased in obese rats as compared with lean rats. Obese rats of the designated WNIN/GR-Ob strain showed obesity with IGT, as adjudged by physical, physiological and biochemical indices. These indices varied among the three phenotypes, being lowest in lean, highest in obese and intermediate in carrier phenotypes thereby suggesting that obesity is inherited as autosomal incomplete dominant trait in this strain. This mutant obese rat model is easy to

  18. Analog electronic model of the lobster pyloric central pattern generator

    Energy Technology Data Exchange (ETDEWEB)

    Volkovskii, A [Institute for Nonlinear Science, University of California San Diego, CA (United States); Brugioni, S [Institute for Nonlinear Science, University of California San Diego, CA (United States); Istituto Nazionale di Ottica Applicata Largo E. Fermi 6 50125 Florence (Italy); Levi, R [Institute for Nonlinear Science, University of California San Diego, CA (United States); Rabinovich, M [Institute for Nonlinear Science, University of California San Diego, CA (United States); Selverston, A [Institute for Nonlinear Science, University of California San Diego, CA (United States); Abarbane, H D I [Institute for Nonlinear Science, University of California San Diego, CA (United States)

    2005-01-01

    An electronic circuit intended to simulate the nonlinear dynamics of a simplified 3-cell model of the pyloric central pattern generator in California spiny lobster stomato gastric ganglion is presented. The model employs the synaptic phase locked loop (SPLL) concept where the frequency of oscillations of a postsynaptic cell is mainly controlled by the synaptic current which depends on the phase shift between the oscillations. The theoretical study showed that the system has a stable steady state with correct phase shifts between the oscillations and that this regime is stable when the frequency of the pacemaker cell is varied over a wide range. The main bifurcations in the system were studied analytically, in computer simulations, and in experiments with the electronic circuit. The experimental measurements are in good agreement with the expectations of the theoretical model.

  19. A theoretical model on surface electronic behavior: Strain effect

    International Nuclear Information System (INIS)

    Qin, W.G.; Shaw, D.

    2009-01-01

    Deformation from mechanical loading can affect surface electronic behavior. Surface deformation and electronic behavior can be quantitatively expressed using strain and work function, respectively, and their experimental relationship can be readily determined using the Kelvin probing technique. However, the theoretical correlation between work function and strain has been unclear. This study reports our theoretical exploration, for the first time, of the effect of strain on work function. We propose a simple electrostatic action model by considering the effect of a dislocation on work function of a one-dimensional lattice and further extend this model to the complex conditions for the effect of dislocation density. Based on this model, we established successfully a theoretical correlation between work function and strain.

  20. The Development Model Electronic Commerce of Regional Agriculture

    Science.gov (United States)

    Kang, Jun; Cai, Lecai; Li, Hongchan

    With the developing of the agricultural information, it is inevitable trend of the development of agricultural electronic commercial affairs. On the basis of existing study on the development application model of e-commerce, combined with the character of the agricultural information, compared with the developing model from the theory and reality, a new development model electronic commerce of regional agriculture base on the government is put up, and such key issues as problems of the security applications, payment mode, sharing mechanisms, and legal protection are analyzed, etc. The among coordination mechanism of the region is discussed on, it is significance for regulating the development of agricultural e-commerce and promoting the regional economical development.

  1. Effects of Chinese herbal medicine Yinsiwei compound on spatial learning and memory ability and the ultrastructure of hippocampal neurons in a rat model of sporadic Alzheimer disease.

    Science.gov (United States)

    Diwu, Yong-chang; Tian, Jin-zhou; Shi, Jing

    2011-02-01

    To study the effects of Chinese herbal medicine Yinsiwei compound (YSW) on spatial learning and memory ability in rats with sporadic Alzheimer disease (SAD) and the ultrastructural basis of the hippocampal neurons. A rat model of SAD was established by intracerebroventricular injection of streptozotocin. The rats were divided into six groups: sham-operation group, model group, donepezil control group, and YSW low, medium and high dose groups. Drug interventions were started on the 21st day after modeling and each treatment group was given the corresponding drugs by gavage for two months. Meanwhile, the model group and the sham-operation group were given the same volume of distilled water by gavage once a day for two months. The Morris water maze was adopted to test spatial learning and memory ability of the rats. The place navigation test and the spatial probe test were conducted. The escape latency, total swimming distance and swimming time in the target quadrant of the rats were recorded. Also, the hippocampus tissues of rats were taken out and the ultrastructure of hippocampus neurons were observed by an electron microscope. In the place navigation test, compared with the model group, the mean escape latency and the total swimming distance of the donepezil group and the YSW low, medium and high dose groups were significantly shortened (Pmicroscope also confirmed the efficacy of the drug treatment. Chinese herbal medicine YSW compound can improve spatial learning and memory impairment of rats with SAD. The ultrastructural basis may be that it can protect the microtubule structures of hippocampal neurons and prevent nerve axons from being damaged.

  2. Dynamics of myelin content decrease in the rat stroke model

    Science.gov (United States)

    Kisel, A.; Khodanovich, M.; Atochin, D.; Mustafina, L.; Yarnykh, V.

    2017-08-01

    The majority of studies were usually focused on neuronal death after brain ischemia; however, stroke affects all cell types including oligodendrocytes that form myelin sheath in the CNS. Our study is focused on the changes of myelin content in the ischemic core and neighbor structures in early terms (1, 3 and 10 days) after stroke. Stroke was modeled with middle cerebral artery occlusion (MCAo) in 15 male rats that were divided into three groups by time points after operation. Brain sections were histologically stained with Luxol Fast Blue (LFB) for myelin quantification. The significant demyelination was found in the ischemic core, corpus callosum, anterior commissure, whereas myelin content was increased in caudoputamen, internal capsule and piriform cortex compared with the contralateral hemisphere. The motor cortex showed a significant increase of myelin content on the 1st day and a significant decrease on the 3rd and 10th days after MCAo. These results suggest that stroke influences myelination not only in the ischemic core but also in distant structures.

  3. Rat animal model for preclinical testing of microparticle urethral bulking agents.

    Science.gov (United States)

    Mann-Gow, Travis K; Blaivas, Jerry G; King, Benjamin J; El-Ghannam, Ahmed; Knabe, Christine; Lam, Michael K; Kida, Masatoshi; Sikavi, Cameron S; Plante, Mark K; Krhut, Jan; Zvara, Peter

    2015-04-01

    To develop an economic, practical and readily available animal model for preclinical testing of urethral bulking therapies, as well as to establish feasible experimental methods that allow for complete analysis of hard microparticle bulking agents. Alumina ceramic beads suspended in hyaluronic acid were injected into the proximal urethra of 15 female rats under an operating microscope. We assessed overall lower urinary tract function, bulking material intraurethral integrity and local host tissue response over time. Microphotographs were taken during injection and again 6 months postoperatively, before urethral harvest. Urinary flow rate and voiding frequency were assessed before and after injection. At 6 months, the urethra was removed and embedded in resin. Hard tissue sections were cut using a sawing microtome, and processed for histological analysis using scanning electron microscopy, light microscopy and immunohistochemistry. Microphotographs of the urethra showed complete volume retention of the bulking agent at 6 months. There was no significant difference between average urinary frequency and mean urinary flow rate at 1 and 3 months postinjection as compared with baseline. Scanning electron microscopy proved suitable for evaluation of microparticle size and integrity, as well as local tissue remodeling. Light microscopy and immunohistochemistry allowed for evaluation of an inflammatory host tissue reaction to the bulking agent. The microsurgical injection technique, in vivo physiology and novel hard tissue processing for histology, described in the present study, will allow for future comprehensive preclinical testing of urethral bulking therapy agents containing microparticles made of a hard material. © 2015 The Japanese Urological Association.

  4. Modeling CICR in rat ventricular myocytes: voltage clamp studies

    Directory of Open Access Journals (Sweden)

    Palade Philip T

    2010-11-01

    Full Text Available Abstract Background The past thirty-five years have seen an intense search for the molecular mechanisms underlying calcium-induced calcium-release (CICR in cardiac myocytes, with voltage clamp (VC studies being the leading tool employed. Several VC protocols including lowering of extracellular calcium to affect Ca2+ loading of the sarcoplasmic reticulum (SR, and administration of blockers caffeine and thapsigargin have been utilized to probe the phenomena surrounding SR Ca2+ release. Here, we develop a deterministic mathematical model of a rat ventricular myocyte under VC conditions, to better understand mechanisms underlying the response of an isolated cell to calcium perturbation. Motivation for the study was to pinpoint key control variables influencing CICR and examine the role of CICR in the context of a physiological control system regulating cytosolic Ca2+ concentration ([Ca2+]myo. Methods The cell model consists of an electrical-equivalent model for the cell membrane and a fluid-compartment model describing the flux of ionic species between the extracellular and several intracellular compartments (cell cytosol, SR and the dyadic coupling unit (DCU, in which resides the mechanistic basis of CICR. The DCU is described as a controller-actuator mechanism, internally stabilized by negative feedback control of the unit's two diametrically-opposed Ca2+ channels (trigger-channel and release-channel. It releases Ca2+ flux into the cyto-plasm and is in turn enclosed within a negative feedback loop involving the SERCA pump, regulating[Ca2+]myo. Results Our model reproduces measured VC data published by several laboratories, and generates graded Ca2+ release at high Ca2+ gain in a homeostatically-controlled environment where [Ca2+]myo is precisely regulated. We elucidate the importance of the DCU elements in this process, particularly the role of the ryanodine receptor in controlling SR Ca2+ release, its activation by trigger Ca2+, and its

  5. About the free electron model in electric conduction of metals

    International Nuclear Information System (INIS)

    Hoffmann, C.

    1991-01-01

    In the model proposed by Drude to describe, among others, the electric conduction in metals, it is supposed that electrons move freely in the material with a time interval between encounters T and a probability distribution g(t). The name, 'electron pause time', will be assigned to the time T with that probability distribution. The calculations made by Drude turned out to be erroneous. The error can be corrected observing that the random variable 'pause time' appearing in this intuitive idea is not the previously defined random variable T, 'electron pause time', but another random variable S, which will be called 'observed pause time' whose probability density is Csg(s), where C is a normalization constant. With this distribution, the characteristics of the distribution, q(u), of the wait time can be obtained. (Author) [es

  6. Improving CASINO performance for models with large number of electrons

    International Nuclear Information System (INIS)

    Anton, L.; Alfe, D.; Hood, R.Q.; Tanqueray, D.

    2009-01-01

    Quantum Monte Carlo calculations have at their core algorithms based on statistical ensembles of multidimensional random walkers which are straightforward to use on parallel computers. Nevertheless some computations have reached the limit of the memory resources for models with more than 1000 electrons because of the need to store a large amount of electronic orbitals related data. Besides that, for systems with large number of electrons, it is interesting to study if the evolution of one configuration of random walkers can be done faster in parallel. We present a comparative study of two ways to solve these problems: (1) distributed orbital data done with MPI or Unix inter-process communication tools, (2) second level parallelism for configuration computation

  7. Modeling power electronics and interfacing energy conversion systems

    CERN Document Server

    Simões, Marcelo Godoy

    2017-01-01

    Discusses the application of mathematical and engineering tools for modeling, simulation and control oriented for energy systems, power electronics and renewable energy. This book builds on the background knowledge of electrical circuits, control of dc/dc converters and inverters, energy conversion and power electronics. The book shows readers how to apply computational methods for multi-domain simulation of energy systems and power electronics engineering problems. Each chapter has a brief introduction on the theoretical background, a description of the problems to be solved, and objectives to be achieved. Block diagrams, electrical circuits, mathematical analysis or computer code are covered. Each chapter concludes with discussions on what should be learned, suggestions for further studies and even some experimental work.

  8. Modeling and Control of a teletruck using electronic load sensing

    DEFF Research Database (Denmark)

    Hansen, Rico Hjerm; Iversen, Asger Malte; Jensen, Mads Schmidt

    2010-01-01

    system is most commonly controlled using a hydro-mechanical control scheme called Hydraulic Load Sensing (HLS). However, with the demands for increased efficiency and controllability the HLS solutions are reaching their limits. Motivated by availability of electronic controllable fluid power...... components and the potential of increased dynamic performance and efficiency, this paper investigates how HLS can be replaced with electronic control, i.e. Electronic Load Sensing (ELS). The investigation is performed by taking a specific application, a teletruck, and replace the HLS control with ELS. To aid...... the controller design for the ELS system, a complete model of the teletruck’s articulated arm and fluid power system is developed. To show the feasibility, a preliminary control structure for the ELS system is developed. The controller is tested on the machine, validating that features such as pump pressure...

  9. Statistics of excitations in the electron glass model

    Science.gov (United States)

    Palassini, Matteo

    2011-03-01

    We study the statistics of elementary excitations in the classical electron glass model of localized electrons interacting via the unscreened Coulomb interaction in the presence of disorder. We reconsider the long-standing puzzle of the exponential suppression of the single-particle density of states near the Fermi level, by measuring accurately the density of states of charged and electron-hole pair excitations via finite temperature Monte Carlo simulation and zero-temperature relaxation. We also investigate the statistics of large charge rearrangements after a perturbation of the system, which may shed some light on the slow relaxation and glassy phenomena recently observed in a variety of Anderson insulators. In collaboration with Martin Goethe.

  10. Calorie restriction attenuates cardiac remodeling and diastolic dysfunction in a rat model of metabolic syndrome.

    Science.gov (United States)

    Takatsu, Miwa; Nakashima, Chieko; Takahashi, Keiji; Murase, Tamayo; Hattori, Takuya; Ito, Hiromi; Murohara, Toyoaki; Nagata, Kohzo

    2013-11-01

    Calorie restriction (CR) can modulate the features of obesity-related metabolic and cardiovascular diseases. We have recently characterized DahlS.Z-Lepr(fa)/Lepr(fa) (DS/obese) rats, derived from a cross between Dahl salt-sensitive and Zucker rats, as a new animal model of metabolic syndrome. DS/obese rats develop hypertension and manifest left ventricular remodeling and diastolic dysfunction, as well as increased cardiac oxidative stress and inflammation. We have now investigated the effects of CR on cardiac pathophysiology in DS/obese rats. DS/obese rats were fed either normal laboratory chow ad libitum or a calorie-restricted diet (65% of the average food intake for ad libitum) from 9 to 13 weeks. Age-matched homozygous lean (DahlS.Z-Lepr(+)/Lepr(+) or DS/lean) littermates served as controls. CR reduced body weight in both DS/obese and DS/lean rats, as well as attenuated the development of hypertension in DS/obese rats without affecting blood pressure in DS/lean rats. CR also reduced body fat content, ameliorated left ventricular hypertrophy, fibrosis, and diastolic dysfunction, and attenuated cardiac oxidative stress and inflammation in DS/obese rats. In addition, it increased serum adiponectin concentration, as well as downregulated the expression of angiotensin-converting enzyme and angiotensin II type 1A receptor genes in the heart of DS/obese rats. Our results thus show that CR attenuated obesity and hypertension, as well as left ventricular remodeling and diastolic dysfunction in DS/obese rats, with these latter effects being associated with reduced cardiac oxidative stress and inflammation.

  11. Effect of Sirtuin-1 on Synaptic Plasticity in Nucleus Accumbens in a Rat Model of Heroin Addiction.

    Science.gov (United States)

    Xia, Baijuan; Li, Yixin; Li, Rongrong; Yin, Dan; Chen, Xingqiang; Li, Jie; Liang, Wenmei

    2018-06-05

    BACKGROUND Synaptic plasticity plays an important role in the process of addiction. This study investigated the relationship between synaptic plasticity and changes in addictive behavior and examined the expression of synaptic plasticity-associated proteins and genes in the nucleus accumbens (NAc) region in different rat models. MATERIAL AND METHODS Heroin addiction, SIRT1-overexpression, and SIRT1-silenced rat models were established. Polymerase chain reaction gene chip technology, immunohistochemistry, Western blotting, and transmission electron microscopy were used to detect changes in synaptic plasticity-related gene and protein expression, and changes in the ultrastructure of synapses, in the NAc. RESULTS Naloxone withdrawal symptoms appeared in the SIRT1-overexpression group. In the SIRT1-silenced group the symptoms were reduced. Immunohistochemistry and Western blotting results showed that FOXO1 expression decreased in the heroin addiction (HA) group but increased in the SIRT1-silenced group (paddiction. SIRT1 overexpression can increase behavioral sensitization in the NAc of rats, and SIRT1 silencing might ease withdrawal symptoms and reduce conditioned place preferences.

  12. Lemon juice has protective activity in a rat urolithiasis model

    OpenAIRE

    Touhami, Mohammed; Laroubi, Amine; Elhabazi, Khadija; Loubna, Farouk; Zrara, Ibtissam; Eljahiri, Younes; Oussama, Abdelkhalek; Grases, Félix; Chait, Abderrahman

    2007-01-01

    Abstract Background The use of herbal medicines (medicinal plants or phytotherapy) has recently gained popularity in Europe and the United States. Nevertheless the exact mechanism of the preventive effects of these products is still far to be clearly established, being its knowledge necessary to successfully apply these therapies to avoid stone formation. Methods The effect of oral lemon juice administration on calcium oxalate urolithiasis was studied in male Wistar rats. Rats were rendered n...

  13. In vivo Dentin Caries Model using Rat Molars

    OpenAIRE

    Takashi, HIGASHI; Junji, TAGAMI; Nobuhiro, HANADA; Cariology and Operative Dentistry, Department of Restorative Sciences, Tokyo Medical and Dental University; Cariology and Operative Dentistry, Department of Restorative Sciences, Tokyo Medical and Dental University; Department of Oral Science The National Institute of Infectious Diseases(NIID)

    2000-01-01

    Experimental dentinal caries was induced in rat molars which were inoculated orally with Streptococcus mutans and maintained on a carionenic diet 2000. After 30 days on the diet, the rats were sacrificed. The caries lesions were confirmed with a caries detector, then nanohardness determination of caries dentin were measured with nanoindentation. After hardness measurement, the lesion was examined by SEM and EDS. Dentin caries in sixteen fissures was induced among 20 fissures in the mandibular...

  14. Effect of Piper sarmentosum Extract on the Cardiovascular System of Diabetic Sprague-Dawley Rats: Electron Microscopic Study

    Directory of Open Access Journals (Sweden)

    Zar Chi Thent

    2012-01-01

    Full Text Available Although Piper sarmentosum (PS is known to possess the antidiabetic properties, its efficacy towards diabetic cardiovascular tissues is still obscured. The present study aimed to observe the electron microscopic changes on the cardiac tissue and proximal aorta of experimental rats treated with PS extract. Thirty-two male Sprague-Dawley rats were divided into four groups: untreated control group (C, PS-treated control group (CTx, untreated diabetic group (D, and PS-treated diabetic group (DTx. Intramuscular injection of streptozotocin (STZ, 50 mg/kg body weight was given to induce diabetes. Following 28 days of diabetes induction, PS extract (0.125 g/kg body weight was administered orally for 28 days. Body weight, fasting blood glucose, and urine glucose levels were measured at 4-week interval. At the end of the study, cardiac tissues and the aorta were viewed under transmission electron microscope (TEM. DTx group showed increase in body weight and decrease in fasting blood glucose and urine glucose level compared to the D group. Under TEM study, DTx group showed lesser ultrastructural degenerative changes in the cardiac tissues and the proximal aorta compared to the D group. The results indicate that PS restores ultrastructural integrity in the diabetic cardiovascular tissues.

  15. Autoimmunity in type 1 diabetes mellitus: a rat model

    International Nuclear Information System (INIS)

    Liu, Z.

    1987-01-01

    In this study, we have sought to isolate in vitro, from acutely diabetic BB rats, cytotoxic T lymphocytes, which exhibit specific cytotoxicity toward islet cells. Thoracic duct lymphocytes (TDL) from acutely diabetic BB rats cultured with irradiated MHC matched (RT1.u) islet cells and dendritic cells in vitro were shown to be specifically cytotoxic to MHC matched and mismatched allogeneic (RT1.1) and xenogeneic (hamster) islet target cells in a 3 H-leucine release assay. Two cell lines (V1A8 and V1D11) derived from the TDL culture showed similar patterns of non-MHC restricted islet cell killing which could be blocked by islet cells and cultured rat insulinoma cells (RIN5mF) but not by non-islet cells of various tissue origins. Both V1A8 and V1D11 were not cytotoxic to Natural Killer (NK) sensitive target cells, G1TC and YAC-1. Conventional surface markers for rat helper and suppressor/cytotoxic T cells were not detectable on either cell lines. The V1D11 cell line was positive for W 3/13 (rat T/NK marker) on OX-19 (rat T/macrophage marker), whereas the V1A8 cell line was only positive for W 3/13

  16. Novel Rat Model of Repetitive Portal Venous Embolization Mimicking Human Non-Cirrhotic Idiopathic Portal Hypertension

    DEFF Research Database (Denmark)

    Klein, Sabine; Hinüber, Christian; Hittatiya, Kanishka

    2016-01-01

    BACKGROUND: Non-cirrhotic idiopathic portal hypertension (NCIPH) is characterized by splenomegaly, anemia and portal hypertension, while liver function is preserved. However, no animal models have been established yet. This study assessed a rat model of NCIPH and characterized the hemodynamics......, and compared it to human NCIPH. METHODS: Portal pressure (PP) was measured invasively and coloured microspheres were injected in the ileocecal vein in rats. This procedure was performed weekly for 3 weeks (weekly embolization). Rats without and with single embolization served as controls. After four weeks (one...... in the weekly embolization group. Fibrotic markers αSMA and Desmin were upregulated in weekly embolized rats. DISCUSSION: This study establishes a model using repetitive embolization via portal veins, comparable with human NCIPH and may serve to test new therapies....

  17. Topiramate as a neuroprotective agent in a rat model of spinal cord injury

    Directory of Open Access Journals (Sweden)

    Firat Narin

    2017-01-01

    Full Text Available Topiramate (TPM is a widely used antiepileptic and antimigraine agent which has been shown to exert neuroprotective effects in various experimental traumatic brain injury and stroke models. However, its utility in spinal cord injury has not been studied extensively. Thus, we evaluated effects of TPM on secondary cellular injury mechanisms in an experimental rat model of traumatic spinal cord injury (SCI. After rat models of thoracic contusive SCI were established by free weight-drop method, TPM (40 mg/kg was given at 12-hour intervals for four times orally. Post TPM treatment, malondialdehyde and protein carbonyl levels were significantly reduced and reduced glutathione levels were increased, while immunoreactivity for endothelial nitric oxide synthase, inducible nitric oxide synthase, and apoptotic peptidase activating factor 1 was diminished in SCI rats. In addition, TPM treatment improved the functional recovery of SCI rats. This study suggests that administration of TPM exerts neuroprotective effects on SCI.

  18. Establishment of SHG-44 human glioma model in brain of wistar rat with stereotactic technique

    International Nuclear Information System (INIS)

    Hong Xinyu; Luo Yi'nan; Fu Shuanglin; Wang Zhanfeng; Bie Li; Cui Jiale

    2004-01-01

    Objective: To establish solid intracerebral human glioma model in Wistar rat with xenograft methods. Methods: The SHG-44 cells were injected into brain right caudate nucleus of previous immuno-inhibitory Wistar rats with stereotactic technique. The MRI scans were performed at 1 week and 2 weeks later after implantation. After 2 weeks the rats were killed and pathological examination and immunohistologic stain for human GFAP were used. Results: The MRI scan after 1 week of implantation showed the glioma was growing, pathological histochemical examination demonstrated the tumor was glioma. Human GFAP stain was positive. The growth rate of glioma model was about 60%. Conclusion: Solid intracerebral human glioma model in previous immuno-inhibitory Wistar rat is successfully established

  19. Power electronic converters modeling and control with case studies

    CERN Document Server

    Bacha, Seddik; Bratcu, Antoneta Iuliana

    2014-01-01

    Modern power electronic converters are involved in a very broad spectrum of applications: switched-mode power supplies, electrical-machine-motion-control, active power filters, distributed power generation, flexible AC transmission systems, renewable energy conversion systems and vehicular technology, among them. Power Electronics Converters Modeling and Control teaches the reader how to analyze and model the behavior of converters and so to improve their design and control. Dealing with a set of confirmed algorithms specifically developed for use with power converters, this text is in two parts: models and control methods. The first is a detailed exposition of the most usual power converter models: ·        switched and averaged models; ·        small/large-signal models; and ·        time/frequency models. The second focuses on three groups of control methods: ·        linear control approaches normally associated with power converters; ·        resonant controllers b...

  20. Translational mixed-effects PKPD modelling of recombinant human growth hormone - from hypophysectomized rat to patients

    DEFF Research Database (Denmark)

    Thorsted, A; Thygesen, P; Agersø, H

    2016-01-01

    BACKGROUND AND PURPOSE: We aimed to develop a mechanistic mixed-effects pharmacokinetic (PK)-pharmacodynamic (PD) (PKPD) model for recombinant human growth hormone (rhGH) in hypophysectomized rats and to predict the human PKPD relationship. EXPERIMENTAL APPROACH: A non-linear mixed-effects model...... was developed from experimental PKPD studies of rhGH and effects of long-term treatment as measured by insulin-like growth factor 1 (IGF-1) and bodyweight gain in rats. Modelled parameter values were scaled to human values using the allometric approach with fixed exponents for PKs and unscaled for PDs...... s.c. administration was over predicted. After correction of the human s.c. absorption model, the induction model for IGF-1 well described the human PKPD data. CONCLUSIONS: A translational mechanistic PKPD model for rhGH was successfully developed from experimental rat data. The model links...

  1. Effect of Qingnao tablet on blood viscosity of rat model of blood stasis induced by epinephrine

    Science.gov (United States)

    Xie, Guoqi; Hao, Shaojun; Ma, Zhenzhen; Liu, Xiaobin; Li, Jun; Li, Wenjun; Zhang, Zhengchen

    2018-04-01

    To establish a rat model of blood stasis with adrenaline (Adr) subcutaneous injection and ice bath stimulation. The effects of different doses on the blood viscosity of blood stasis model rats were observed. The rats were randomly divided into 6 groups: blank control group (no model), model group, positive control group, high, middle and low dose group. The whole blood viscosity and plasma viscosity were detected by blood viscosity instrument. Compared with the blank group, model group, high shear, low shear whole blood viscosity and plasma viscosity were significantly increased, TT PT significantly shortened, APTT was significantly prolonged, FIB increased significantly, indicating that the model was successful. Compared with the model group, can significantly reduce the Naoluotong group (cut, low cut). Qingnaopian high dose group (low cut), middle dose group (cut, low shear blood viscosity) (Pgroup, high dose group (Pgroup (Pblood rheology of blood stasis mice abnormal index, decrease the blood viscosity, blood stasis has certain hemostatic effect.

  2. Assessment of multislice CT to quantify pulmonary emphysema function and physiology in a rat model

    Science.gov (United States)

    Cao, Minsong; Stantz, Keith M.; Liang, Yun; Krishnamurthi, Ganapathy; Presson, Robert G., Jr.

    2005-04-01

    Purpose: The purpose of this study is to evaluate multi-slice computed tomography technology to quantify functional and physiologic changes in rats with pulmonary emphysema. Method: Seven rats were scanned using a 16-slice CT (Philips MX8000 IDT) before and after artificial inducement of emphysema. Functional parameters i.e. lung volumes were measured by non-contrast spiral scan during forced breath-hold at inspiration and expiration followed by image segmentation based on attenuation threshold. Dynamic CT imaging was performed immediately following the contrast injection to estimate physiology changes. Pulmonary perfusion, fractional blood volume, and mean transit times (MTTs) were estimated by fitting the time-density curves of contrast material using a compartmental model. Results: The preliminary results indicated that the lung volumes of emphysema rats increased by 3.52+/-1.70mL (pemphysema rats decreased by 91.76+/-68.11HU (pemphysema rats were 0.25+/-0.04ml/s/ml and 0.32+/-0.09ml/s/ml respectively. The fractional blood volumes for normal and emphysema rats were 0.21+/-0.04 and 0.15+/-0.02. There was a trend toward faster MTTs for emphysema rats (0.42+/-0.08s) than normal rats (0.89+/-0.19s) with ppulmonary emphysema appears promising for small animals.

  3. Modeling and multidimensional optimization of a tapered free electron laser

    Directory of Open Access Journals (Sweden)

    Y. Jiao

    2012-05-01

    Full Text Available Energy extraction efficiency of a free electron laser (FEL can be greatly increased using a tapered undulator and self-seeding. However, the extraction rate is limited by various effects that eventually lead to saturation of the peak intensity and power. To better understand these effects, we develop a model extending the Kroll-Morton-Rosenbluth, one-dimensional theory to include the physics of diffraction, optical guiding, and radially resolved particle trapping. The predictions of the model agree well with that of the GENESIS single-frequency numerical simulations. In particular, we discuss the evolution of the electron-radiation interaction along the tapered undulator and show that the decreasing of refractive guiding is the major cause of the efficiency reduction, particle detrapping, and then saturation of the radiation power. With this understanding, we develop a multidimensional optimization scheme based on GENESIS simulations to increase the energy extraction efficiency via an improved taper profile and variation in electron beam radius. We present optimization results for hard x-ray tapered FELs, and the dependence of the maximum extractable radiation power on various parameters of the initial electron beam, radiation field, and the undulator system. We also study the effect of the sideband growth in a tapered FEL. Such growth induces increased particle detrapping and thus decreased refractive guiding that together strongly limit the overall energy extraction efficiency.

  4. Rats

    Directory of Open Access Journals (Sweden)

    Alexey Kondrashov

    2012-01-01

    Full Text Available We aimed to perform a chemical analysis of both Alibernet red wine and an alcohol-free Alibernet red wine extract (AWE and to investigate the effects of AWE on nitric oxide and reactive oxygen species production as well as blood pressure development in normotensive Wistar Kyoto (WKY and spontaneously hypertensive rats (SHRs. Total antioxidant capacity together with total phenolic and selected mineral content was measured in wine and AWE. Young 6-week-old male WKY and SHR were treated with AWE (24,2 mg/kg/day for 3 weeks. Total NOS and SOD activities, eNOS and SOD1 protein expressions, and superoxide production were determined in the tissues. Both antioxidant capacity and phenolic content were significantly higher in AWE compared to wine. The AWE increased NOS activity in the left ventricle, aorta, and kidney of SHR, while it did not change NOS activity in WKY rats. Similarly, increased SOD activity in the plasma and left ventricle was observed in SHR only. There were no changes in eNOS and SOD1 expressions. In conclusion, phenolics and minerals included in AWE may contribute directly to increased NOS and SOD activities of SHR. Nevertheless, 3 weeks of AWE treatment failed to affect blood pressure of SHR.

  5. Epithelial cell kinetics in mouse and rat skin irradiated with electrons

    International Nuclear Information System (INIS)

    McMaster-Schuyler, L.

    1984-02-01

    Experiments were performed to examine the kinetic responses of mouse and rat epidermal cells in vivo after single doses of ionizing radiation including responses of hair follicles at times after irradiation. The labeling indices in both species were reduced to 30 to 50% of control values immediately following irradiation at all the doses. In the rat, the labeling indices recovered and overshot control values within the first three days after 300 to 1200 rads. The mouse labeling indices continued to be suppressed for up to 10 days after 300 to 2400 rads. This indicated that rat G 1 phase epidermal cells recovered three times faster than those of the mouse with respect to the ability to maintain or increase control level cell proliferation after irradiation. After 1800 and 2400 rads, doses which produce skin ulceration, both species showed a reduction in their labeling indices for up to 7 days, indicating that a dose-dependent mechanism of recovery may be operable in the rat. 99 refs., 15 figs., 6 tabs

  6. Comparison of blood biochemics between acute myocardial infarction models with blood stasis and simple acute myocardial infarction models in rats

    International Nuclear Information System (INIS)

    Qu Shaochun; Yu Xiaofeng; Wang Jia; Zhou Jinying; Xie Haolin; Sui Dayun

    2010-01-01

    Objective: To construct the acute myocardial infarction models in rats with blood stasis and study the difference on blood biochemics between the acute myocardial infarction models with blood stasis and the simple acute myocardial infarction models. Methods: Wistar rats were randomly divided into control group, acute blood stasis model group, acute myocardial infarction sham operation group, acute myocardial infarction model group and of acute myocardial infarction model with blood stasis group. The acute myocardial infarction models under the status of the acute blood stasis in rats were set up. The serum malondialdehyde (MDA), nitric oxide (NO), free fatty acid (FFA), tumor necrosis factor-α (TNF-α) levels were detected, the activities of serum superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the levels of prostacycline (PGI2), thromboxane A 2 (TXA 2 ) and endothelin (ET) in plasma were determined. Results: There were not obvious differences in MDA, SOD, GSH-Px and FFA between the acute myocardial infarction models with blood stasis in rats and the simple acute myocardial infarction models (P 2 and NO, and the increase extents of TXA 2 , ET and TNF-α in the acute myocardial infarction models in rats with blood stasis were higher than those in the simple acute myocardial infarction models (P 2 and NO, are significant when the acute myocardial infarction models in rats with blood stasis and the simple acute myocardial infarction models are compared. The results show that it is defective to evaluate pharmacodynamics of traditional Chinese drug with only simple acute myocardial infarction models. (authors)

  7. Two-point model for electron transport in EBT

    International Nuclear Information System (INIS)

    Chiu, S.C.; Guest, G.E.

    1980-01-01

    The electron transport in EBT is simulated by a two-point model corresponding to the central plasma and the edge. The central plasma is assumed to obey neoclassical collisionless transport. The edge plasma is assumed turbulent and modeled by Bohm diffusion. The steady-state temperatures and densities in both regions are obtained as functions of neutral influx and microwave power. It is found that as the neutral influx decreases and power increases, the edge density decreases while the core density increases. We conclude that if ring instability is responsible for the T-M mode transition, and if stability is correlated with cold electron density at the edge, it will depend sensitively on ambient gas pressure and microwave power

  8. Access Control Model for Sharing Composite Electronic Health Records

    Science.gov (United States)

    Jin, Jing; Ahn, Gail-Joon; Covington, Michael J.; Zhang, Xinwen

    The adoption of electronically formatted medical records, so called Electronic Health Records (EHRs), has become extremely important in healthcare systems to enable the exchange of medical information among stakeholders. An EHR generally consists of data with different types and sensitivity degrees which must be selectively shared based on the need-to-know principle. Security mechanisms are required to guarantee that only authorized users have access to specific portions of such critical record for legitimate purposes. In this paper, we propose a novel approach for modelling access control scheme for composite EHRs. Our model formulates the semantics and structural composition of an EHR document, from which we introduce a notion of authorized zones of the composite EHR at different granularity levels, taking into consideration of several important criteria such as data types, intended purposes and information sensitivities.

  9. Modeling Electronic Circular Dichroism within the Polarizable Embedding Approach

    DEFF Research Database (Denmark)

    Nørby, Morten S; Olsen, Jógvan Magnus Haugaard; Steinmann, Casper

    2017-01-01

    We present a systematic investigation of the key components needed to model single chromophore electronic circular dichroism (ECD) within the polarizable embedding (PE) approach. By relying on accurate forms of the embedding potential, where especially the inclusion of local field effects...... are in focus, we show that qualitative agreement between rotatory strength parameters calculated by full quantum mechanical calculations and the more efficient embedding calculations can be obtained. An important aspect in the computation of reliable absorption parameters is the need for conformational...... sampling. We show that a significant number of snapshots are needed to avoid artifacts in the calculated electronic circular dichroism parameters due to insufficient configurational sampling, thus highlighting the efficiency of the PE model....

  10. Use of mathematical modelling in electron beam processing: A guidebook

    International Nuclear Information System (INIS)

    2010-01-01

    The use of electron beam irradiation for industrial applications, like the sterilization of medical devices or cross-linking of polymers, has a long and successful track record and has proven itself to be a key technology. Emerging fields, including environmental applications of ionizing radiation, the sterilization of complex medical and pharmaceutical products or advanced material treatment, require the design and control of even more complex irradiators and irradiation processes. Mathematical models can aid the design process, for example by calculating absorbed dose distributions in a product, long before any prototype is built. They support process qualification through impact assessment of process variable uncertainties, and can be an indispensable teaching tool for technologists in training in the use of radiation processing. The IAEA, through various mechanisms, including its technical cooperation programme, coordinated research projects, technical meetings, guidelines and training materials, is promoting the use of radiation technologies to minimize the effects of harmful contaminants and develop value added products originating from low cost natural and human made raw materials. The need to publish a guidebook on the use of mathematical modelling for design processes in the electron beam treatment of materials was identified through the increased interest of radiation processing laboratories in Member States and as a result of recommendations from several IAEA expert meetings. In response, the IAEA has prepared this report using the services of an expert in the field. This publication should serve as both a guidebook and introductory tutorial for the use of mathematical modelling (using mostly Monte Carlo methods) in electron beam processing. The emphasis of this guide is on industrial irradiation methodologies with a strong reference to existing literature and applicable standards. Its target audience is readers who have a basic understanding of electron

  11. Transverse Momentum Distributions of Electron in Simulated QED Model

    Science.gov (United States)

    Kaur, Navdeep; Dahiya, Harleen

    2018-05-01

    In the present work, we have studied the transverse momentum distributions (TMDs) for the electron in simulated QED model. We have used the overlap representation of light-front wave functions where the spin-1/2 relativistic composite system consists of spin-1/2 fermion and spin-1 vector boson. The results have been obtained for T-even TMDs in transverse momentum plane for fixed value of longitudinal momentum fraction x.

  12. Tamoxifen induces regression of estradiol-induced mammary cancer in ACI.COP-Ept2 rat model

    OpenAIRE

    Ruhlen, Rachel L.; Willbrand, Dana M.; Besch-Williford, Cynthia L.; Ma, Lixin; Shull, James D.; Sauter, Edward R.

    2008-01-01

    The ACI rat is a unique model of human breast cancer in that mammary cancers are induced by estrogen without carcinogens, irradiation, xenografts or transgenic manipulations. We sought to characterize mammary cancers in a congenic variant of the ACI rat, the ACI.COP-Ept2. All rats with estradiol implants developed mammary cancers in 5–7 months. Rats bearing estradiol-induced mammary cancers were treated with tamoxifen for three weeks. Tamoxifen reduced tumor mass, measured by magnetic resonan...

  13. Cardiovascular disease-related parameters and oxidative stress in SHROB rats, a model for metabolic syndrome.

    Directory of Open Access Journals (Sweden)

    Eunice Molinar-Toribio

    Full Text Available SHROB rats have been suggested as a model for metabolic syndrome (MetS as a situation prior to the onset of CVD or type-2 diabetes, but information on descriptive biochemical parameters for this model is limited. Here, we extensively evaluate parameters related to CVD and oxidative stress (OS in SHROB rats. SHROB rats were monitored for 15 weeks and compared to a control group of Wistar rats. Body weight was recorded weekly. At the end of the study, parameters related to CVD and OS were evaluated in plasma, urine and different organs. SHROB rats presented statistically significant differences from Wistar rats in CVD risk factors: total cholesterol, LDL-cholesterol, triglycerides, apoA1, apoB100, abdominal fat, insulin, blood pressure, C-reactive protein, ICAM-1 and PAI-1. In adipose tissue, liver and brain, the endogenous antioxidant systems were activated, yet there was no significant oxidative damage to lipids (MDA or proteins (carbonylation. We conclude that SHROB rats present significant alterations in parameters related to inflammation, endothelial dysfunction, thrombotic activity, insulin resistance and OS measured in plasma as well as enhanced redox defence systems in vital organs that will be useful as markers of MetS and CVD for nutrition interventions.

  14. In vivo micro-CT analysis of bone remodeling in a rat calvarial defect model

    Energy Technology Data Exchange (ETDEWEB)

    Umoh, Joseph U; Holdsworth, David W [Pre-Clinical Imaging Research Centre, Robarts Research Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, PO Box 5015, 100 Perth Drive, London, ON N6A 5K8 (Canada); Sampaio, Arthur V; Underhill, T Michael [Laboratory of Molecular Skeletogenesis, Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC (Canada); Welch, Ian [Animal Care and Veterinary Services, University of Western Ontario, London, ON (Canada); Pitelka, Vasek; Goldberg, Harvey A [CIHR Group in Skeletal Development and Remodelling, University of Western Ontario, London, ON (Canada)], E-mail: jumoh@imaging.robarts.ca, E-mail: asampaio@interchange.ubc.ca, E-mail: tunderhi@interchange.ubc.ca, E-mail: iwelch@uwo.ca, E-mail: vasek.pitelka@schulich.uwo.ca, E-mail: hagoldbe@uwo.ca, E-mail: david.holdsworth@imaging.robarts.ca

    2009-04-07

    The rodent calvarial defect model is commonly used to investigate bone regeneration and wound healing. This study presents a micro-computed tomography (micro-CT) methodology for measuring the bone mineral content (BMC) in a rat calvarial defect and validates it by estimating its precision error. Two defect models were implemented. A single 6 mm diameter defect was created in 20 rats, which were imaged in vivo for longitudinal experiments. Three 5 mm diameter defects were created in three additional rats, which were repeatedly imaged ex vivo to determine precision. Four control rats and four rats treated with bone morphogenetic protein were imaged at 3, 6, 9 and 12 weeks post-surgery. Scan parameters were 80 kVp, 0.45 mA and 180 mAs. Images were reconstructed with an isotropic resolution of 45 {mu}m. At 6 weeks, the BMC in control animals (4.37 {+-} 0.66 mg) was significantly lower (p < 0.05) than that in treated rats (11.29 {+-} 1.01 mg). Linear regression between the BMC and bone fractional area, from 20 rats, showed a strong correlation (r{sup 2} = 0.70, p < 0.0001), indicating that the BMC can be used, in place of previous destructive analysis techniques, to characterize bone growth. The high precision (2.5%) of the micro-CT methodology indicates its utility in detecting small BMC changes in animals.

  15. Volumetric abnormalities of the brain in a rat model of recurrent headache.

    Science.gov (United States)

    Jia, Zhihua; Tang, Wenjing; Zhao, Dengfa; Hu, Guanqun; Li, Ruisheng; Yu, Shengyuan

    2018-01-01

    Voxel-based morphometry is used to detect structural brain changes in patients with migraine. However, the relevance of migraine and structural changes is not clear. This study investigated structural brain abnormalities based on voxel-based morphometry using a rat model of recurrent headache. The rat model was established by infusing an inflammatory soup through supradural catheters in conscious male rats. Rats were subgrouped according to the frequency and duration of the inflammatory soup infusion. Tactile sensory testing was conducted prior to infusion of the inflammatory soup or saline. The periorbital tactile thresholds in the high-frequency inflammatory soup stimulation group declined persistently from day 5. Increased white matter volume was observed in the rats three weeks after inflammatory soup stimulation, brainstem in the in the low-frequency inflammatory soup-infusion group and cortex in the high-frequency inflammatory soup-infusion group. After six weeks' stimulation, rats showed gray matter volume changes. The brain structural abnormalities recovered after the stimulation was stopped in the low-frequency inflammatory soup-infused rats and persisted even after the high-frequency inflammatory soup stimulus stopped. The changes of voxel-based morphometry in migraineurs may be the result of recurrent headache. Cognition, memory, and learning may play an important role in the chronification of migraines. Reducing migraine attacks has the promise of preventing chronicity of migraine.

  16. Enhanced angular overlap model for nonmetallic f -electron systems

    Science.gov (United States)

    Gajek, Z.

    2005-07-01

    An efficient method of interpretation of the crystal field effect in nonmetallic f -electron systems, the enhanced angular overlap model (EAOM), is presented. The method is established on the ground of perturbation expansion of the effective Hamiltonian for localized electrons and first-principles calculations related to available experimental data. The series of actinide compounds AO2 , oxychalcogenides AOX , and dichalcogenides UX2 where X=S ,Se,Te and A=U ,Np serve as probes of the effectiveness of the proposed method. An idea is to enhance the usual angular overlap model with ab initio calculations of those contributions to the crystal field potential, which cannot be represented by the usual angular overlap model (AOM). The enhancement leads to an improved fitting and makes the approach intrinsically coherent. In addition, the ab initio calculations of the main, AOM-consistent part of the crystal field potential allows one to fix the material-specific relations for the EAOM parameters in the effective Hamiltonian. Consequently, the electronic structure interpretation based on EAOM can be extended to systems of the lowest point symmetries or/and deficient experimental data. Several examples illustrating the promising capabilities of EAOM are given.

  17. Pharmacokinetic-pharmacodynamic modeling of diclofenac in normal and Freund's complete adjuvant-induced arthritic rats

    Science.gov (United States)

    Zhang, Jing; Li, Pei; Guo, Hai-fang; Liu, Li; Liu, Xiao-dong

    2012-01-01

    Aim: To characterize pharmacokinetic-pharmacodynamic modeling of diclofenac in Freund's complete adjuvant (FCA)-induced arthritic rats using prostaglandin E2 (PGE2) as a biomarker. Methods: The pharmacokinetics of diclofenac was investigated using 20-day-old arthritic rats. PGE2 level in the rats was measured using an enzyme immunoassay. A pharmacokinetic-pharmacodynamic (PK-PD) model was developed to illustrate the relationship between the plasma concentration of diclofenac and the inhibition of PGE2 production. The inhibition of diclofenac on lipopolysaccharide (LPS)-induced PGE2 production in blood cells was investigated in vitro. Results: Similar pharmacokinetic behavior of diclofenac was found both in normal and FCA-induced arthritic rats. Diclofenac significantly decreased the plasma levels of PGE2 in both normal and arthritic rats. The inhibitory effect on PGE2 levels in the plasma was in proportion to the plasma concentration of diclofenac. No delay in the onset of inhibition was observed, suggesting that the effect compartment was located in the central compartment. An inhibitory effect sigmoid Imax model was selected to characterize the relationship between the plasma concentration of diclofenac and the inhibition of PGE2 production in vivo. The Imax model was also used to illustrate the inhibition of diclofenac on LPS-induced PGE2 production in blood cells in vitro. Conclusion: Arthritis induced by FCA does not alter the pharmacokinetic behaviors of diclofenac in rats, but the pharmacodynamics of diclofenac is slightly affected. A PK-PD model characterizing an inhibitory effect sigmoid Imax can be used to fit the relationship between the plasma PGE2 and diclofenac levels in both normal rats and FCA-induced arthritic rats. PMID:22842736

  18. Characterization of SV-40 Tag rats as a model to study prostate cancer

    International Nuclear Information System (INIS)

    Harper, Curt E; Patel, Brijesh B; Cook, Leah M; Wang, Jun; Shirai, Tomoyuki; Eltoum, Isam A; Lamartiniere, Coral A

    2009-01-01

    Prostate cancer is the second most frequently diagnosed cancer in men. Animal models that closely mimic clinical disease in humans are invaluable tools in the fight against prostate cancer. Recently, a Simian Virus-40 T-antigen (SV-40 Tag) targeted probasin promoter rat model was developed. This model, however, has not been extensively characterized; hence we have investigated the ontogeny of prostate cancer and determined the role of sex steroid receptor and insulin-like growth factor-1 (IGF-1) signaling proteins in the novel SV-40 Tag rat. The SV-40 Tag rat was histopathologically characterized for time to tumor development, incidence and multiplicity and in the ventral, dorsal, lateral and anterior lobes of the prostate. Immunoassay techniques were employed to measure cell proliferation, apoptosis, and sex steroid receptor and growth factor signaling-related proteins. Steroid hormone concentrations were measured via coated well enzyme linked immunosorbent assay (ELISA) kits. Prostatic intraepithelial neoplasia (PIN) and well-differentiated prostate cancer developed as early as 2 and 10 weeks of age, respectively in the ventral prostate (VP) followed by in the dorsolateral (DLP). At 8 weeks of age, testosterone and dihydrotestosterone (DHT) concentrations in SV-40 Tag rats were increased when compared to non-transgenic rats. High cell proliferation and apoptotic indices were found in VP and DLP of transgenic rats. Furthermore, we observed increased protein expression of androgen receptor, IGF-1, IGF-1 receptor, and extracellular signal-regulated kinases in the prostates of SV-40 Tag rats. The rapid development of PIN and prostate cancer in conjunction with the large prostate size makes the SV-40 Tag rat a useful model for studying prostate cancer. This study provides evidence of the role of sex steroid and growth factor proteins in prostate cancer development and defines appropriate windows of opportunity for preclinical trials and aids in the rational design of

  19. Effect of TheraCyte-encapsulated parathyroid cells on lumbar fusion in a rat model

    OpenAIRE

    Chen, Sung-Hsiung; Huang, Shun-Chen; Lui, Chun-Chung; Lin, Tzu-Ping; Chou, Fong-Fu; Ko, Jih-Yang

    2012-01-01

    Introduction Implantation of TheraCyte 4 × 106 live parathyroid cells can increase the bone marrow density of the spine of ovariectomized rats. There has been no published study examining the effect of such implantation on spinal fusion outcomes. The purpose of this study was to examine the effect of TheraCyte-encapsulated parathyroid cells on posterolateral lumbar fusions in a rat model. Materials and methods Forty Sprague-Dawley rats underwent single-level, intertransverse process spinal fu...

  20. Anti-inflammatory activity of methyl palmitate and ethyl palmitate in different experimental rat models

    Energy Technology Data Exchange (ETDEWEB)

    Saeed, Noha M. [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Egyptian Russian University, Cairo (Egypt); El-Demerdash, Ebtehal [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo (Egypt); Abdel-Rahman, Hanaa M. [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Egyptian Russian University, Cairo (Egypt); Algandaby, Mardi M. [Department of Biology (Botany), Faculty of Science, King Abdulaziz University, Jeddah (Saudi Arabia); Al-Abbasi, Fahad A. [Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah (Saudi Arabia); Abdel-Naim, Ashraf B., E-mail: abnaim@pharma.asu.edu.eg [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo (Egypt)

    2012-10-01

    Methyl palmitate (MP) and ethyl palmitate (EP) are naturally occurring fatty acid esters reported as inflammatory cell inhibitors. In the current study, the potential anti-inflammatory activity of MP and EP was evaluated in different experimental rat models. Results showed that MP and EP caused reduction of carrageenan-induced rat paw edema in addition to diminishing prostaglandin E2 (PGE2) level in the inflammatory exudates. In lipopolysaccharide (LPS)-induced endotoxemia in rats, MP and EP reduced plasma levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). MP and EP decreased NF-κB expression in liver and lung tissues and ameliorated histopathological changes caused by LPS. Topical application of MP and EP reduced ear edema induced by croton oil in rats. In the same animal model, MP and EP reduced neutrophil infiltration, as indicated by decreased myeloperoxidase (MPO) activity. In conclusion, this study demonstrates the effectiveness of MP and EP in combating inflammation in several experimental models. -- Highlights: ► Efficacy of MP and EP in combating inflammation was displayed in several models. ► MP and EP reduced carrageenan-induced rat paw edema and prostaglandin E2 level. ► MP and EP decreased TNF-α and IL-6 levels in experimental endotoxemia. ► MP and EP reduced NF-κB expression and histological changes in rat liver and lung. ► MP and EP reduced croton oil-induced ear edema and neutrophil infiltration.

  1. Cardioprotective Effect of the Compound Yangshen Granule in Rat Models with Acute Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    Xie Ming

    2012-01-01

    Full Text Available The protective effect of Compound Yangshen Granules was observed in myocardial infarction rat model. Rats were randomly divided into 6 groups: the model group, the control group (sham operated, the positive drug group, and small, medium, and large dosage of the Yangshen granule groups, respectively. The rats in the 3 Yangshen granule groups were orally administrated with 0.7 g/kg, 1.4 g/kg, and 2.8 g/kg for 7 consecutive days, whereas the rats of the positive drug group treated with 0.14 g/kg of Danshen Dropping Pills, and rats in the control and model groups orally administrated with saline. The rat model of acute myocardial infarction was established with ligation of coronary artery. Electrocardiograms at different time points, the blood rheology, myocardial enzymes, infarct size, and myocardial morphologic changes were measured. The results demonstrated that the granules could improve blood rheology, decrease st-segment of electrocardiograms and the activities of LDH and CK in serum, reduce myocardial infarction size, and alleviate myocardial histopathologic changes. In addition, the effect of the granules depended on the dose administrated orally. The results suggest that the Yangshen granules could produce cardioprotection effect and have potential benefits in the prevention of ischemic heart disease.

  2. A model for hot electron phenomena: Theory and general results

    International Nuclear Information System (INIS)

    Carrillo, J.L.; Rodriquez, M.A.

    1988-10-01

    We propose a model for the description of the hot electron phenomena in semiconductors. Based on this model we are able to reproduce accurately the main characteristics observed in experiments of electric field transport, optical absorption, steady state photoluminescence and relaxation process. Our theory does not contain free nor adjustable parameters, it is very fast computerwise, and incorporates the main collision mechanisms including screening and phonon heating effects. Our description on a set of nonlinear rate equations in which the interactions are represented by coupling coefficients or effective frequencies. We calculate three coefficients from the characteristic constants and the band structure of the material. (author). 22 refs, 5 figs, 1 tab

  3. Modeling of the atomic and electronic structures of interfaces

    International Nuclear Information System (INIS)

    Sutton, A.P.

    1988-01-01

    Recent tight binding and Car-Parrinello simulations of grain boundaries in semiconductors are reviewed. A critique is given of some models of embrittlement that are based on electronic structure considerations. The structural unit model of grain boundary structure is critically assessed using some results for mixed tilt and twist grain boundaries. A new method of characterizing interfacial structure in terms of bond angle distribution functions is described. A new formulation of thermodynamic properties of interfaces is presented which focusses on the local atomic environment. Effective, temperature dependent N-body atomic interactions are derived for studying grain boundary structure at elevated temperature

  4. Towards model-based testing of electronic funds transfer systems

    OpenAIRE

    Asaadi, H.R.; Khosravi, R.; Mousavi, M.R.; Noroozi, N.

    2010-01-01

    We report on our first experience with applying model-based testing techniques to an operational Electronic Funds Transfer (EFT) switch. The goal is to test the conformance of the EFT switch to the standard flows described by the ISO 8583 standard. To this end, we first make a formalization of the transaction flows specified in the ISO 8583 standard in terms of a Labeled Transition System (LTS). This formalization paves the way for model-based testing based on the formal notion of Input-Outpu...

  5. Fuse Modeling for Reliability Study of Power Electronic Circuits

    DEFF Research Database (Denmark)

    Bahman, Amir Sajjad; Iannuzzo, Francesco; Blaabjerg, Frede

    2017-01-01

    This paper describes a comprehensive modeling approach on reliability of fuses used in power electronic circuits. When fuses are subjected to current pulses, cyclic temperature stress is introduced to the fuse element and will wear out the component. Furthermore, the fuse may be used in a large......, and rated voltage/current are opposed to shift in time to effect early breaking during the normal operation of the circuit. Therefore, in such cases, a reliable protection required for the other circuit components will not be achieved. The thermo-mechanical models, fatigue analysis and thermo...

  6. Postictal in situ MRS brain lactate in the rat kindling model.

    Science.gov (United States)

    Maton, B M; Najm, I M; Wang, Y; Lüders, H O; Ng, T C

    1999-12-10

    To determine the temporal and spatial extent of the lactate (Lact) changes as correlated with seizure characteristics and EEG changes in the rat kindling model. Prior studies using MRS have detected cerebral Lact postictally in animal models of seizures and in patients with intractable focal epilepsy. We performed MRS in sham control rats (n = 4) and in rats stimulated in the right hippocampus at two different stages of the kindling and at three time points after the seizures: 3 hours (n = 4 and 2). Lact/creatine (Cr) and N-acetylaspartate (NAA)/Cr ratios were measured in six contiguous voxels (three left, three right) covering the hippocampi, anterior and posterior regions, and compared with EEG and ictal behavior. Lact/Cr ratios were measured at a very low level in the sham control rats and in the >3-hour group. In the epilepsy.

  7. Rat models of spinal cord injury: from pathology to potential therapies

    Science.gov (United States)

    2016-01-01

    ABSTRACT A long-standing goal of spinal cord injury research is to develop effective spinal cord repair strategies for the clinic. Rat models of spinal cord injury provide an important mammalian model in which to evaluate treatment strategies and to understand the pathological basis of spinal cord injuries. These models have facilitated the development of robust tests for assessing the recovery of locomotor and sensory functions. Rat models have also allowed us to understand how neuronal circuitry changes following spinal cord injury and how recovery could be promoted by enhancing spontaneous regenerative mechanisms and by counteracting intrinsic inhibitory factors. Rat studies have also revealed possible routes to rescuing circuitry and cells in the acute stage of injury. Spatiotemporal and functional studies in these models highlight the therapeutic potential of manipulating inflammation, scarring and myelination. In addition, potential replacement therapies for spinal cord injury, including grafts and bridges, stem primarily from rat studies. Here, we discuss advantages and disadvantages of rat experimental spinal cord injury models and summarize knowledge gained from these models. We also discuss how an emerging understanding of different forms of injury, their pathology and degree of recovery has inspired numerous treatment strategies, some of which have led to clinical trials. PMID:27736748

  8. A novel knee prosthesis model of implant-related osteo- myelitis in rats

    DEFF Research Database (Denmark)

    Søe, Niels H.; Jensen, Nina Vendel; Nürnberg, Birgit Meinecke

    2012-01-01

    There have been numerous reports of animal models of osteomyelitis. Very few of these have been prosthesis models that imitate human conditions. We have developed a new rat model of implant-related osteomyelitis that mimics human osteomyelitis, to investigate the pathology of infection after...

  9. Evaluation by electronic paramagnetic resonance of the number of free radicals produced in irradiated rat bone; Evaluation par resonance paramagnetique electronique du nombre de radicaux libres produits dans l'os de rat irradie

    Energy Technology Data Exchange (ETDEWEB)

    Marble, G; Valderas, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1966-07-01

    The number of long half-life free radicals created by gamma irradiation in the bones of the rat has been determined from the electrons paramagnetic resonance spectrum. This number decreases slowly with time (calculated half life: 24 days). It is proportional to the dose of gamma radiation given to the rat. The method could find interesting applications in the field of biological dosimetry. (authors) [French] Le nombre de radicaux libres a vie longue crees par irradiation gamma dans l'os de rat a ete determine a partir du spectre de resonance paramagnetique electronique. Ce nombre decroit lentement avec le temps (demi-vie calculee {approx_equal} 24 jours). IL est proportionnel a la dose de rayonnement gamma delivree au rat. La methode pourra trouver en dosimetrie biologique des applications interessantes. (auteurs)

  10. Evaluation by electronic paramagnetic resonance of the number of free radicals produced in irradiated rat bone; Evaluation par resonance paramagnetique electronique du nombre de radicaux libres produits dans l'os de rat irradie

    Energy Technology Data Exchange (ETDEWEB)

    Marble, G.; Valderas, R. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1966-07-01

    The number of long half-life free radicals created by gamma irradiation in the bones of the rat has been determined from the electrons paramagnetic resonance spectrum. This number decreases slowly with time (calculated half life: 24 days). It is proportional to the dose of gamma radiation given to the rat. The method could find interesting applications in the field of biological dosimetry. (authors) [French] Le nombre de radicaux libres a vie longue crees par irradiation gamma dans l'os de rat a ete determine a partir du spectre de resonance paramagnetique electronique. Ce nombre decroit lentement avec le temps (demi-vie calculee {approx_equal} 24 jours). IL est proportionnel a la dose de rayonnement gamma delivree au rat. La methode pourra trouver en dosimetrie biologique des applications interessantes. (auteurs)

  11. Long-term characterization of the diet-induced obese and diet-resistant rat model

    DEFF Research Database (Denmark)

    Madsen, Andreas Nygaard; Hansen, Gitte; Paulsen, Sarah Juel

    2010-01-01

    , namely the selectively bred diet-induced obese (DIO) and diet-resistant (DR) rat strains. We show that they constitute useful models of the human obesity syndrome. DIO and DR rats were fed either a high-energy (HE) or a standard chow (Chow) diet from weaning to 9 months of age. Metabolic characterization......, the results underscore the effectiveness of GLP-1 mimetics both as anti-diabetes and anti-obesity agents....

  12. Abnormal air righting behaviour in the spontaneously hypertensive rat model of ADHD

    OpenAIRE

    Dommett, Eleanor J; Rostron, Claire L

    2011-01-01

    The spontaneously hypertensive rat (SHR) is the most commonly used model of attention-deficit hyperactivity disorder (ADHD), displaying the main symptoms of the disorder which are responsive to psychostimulant treatments. Research to date has focused on behavioural tests investigating functioning of the striatum or prefrontal cortex in these rats. However, there is now evidence that the superior colliculus, a structure associated with head and eye movements, may also be dysfunctional in ADHD....

  13. A magnetospheric specification model validation study: Geosynchronous electrons

    Science.gov (United States)

    Hilmer, R. V.; Ginet, G. P.

    2000-09-01

    The Rice University Magnetospheric Specification Model (MSM) is an operational space environment model of the inner and middle magnetosphere designed to specify charged particle fluxes up to 100keV. Validation test data taken between January 1996 and June 1998 consist of electron fluxes measured by a charge control system (CCS) on a defense satellite communications system (DSCS) spacecraft. The CCS includes both electrostatic analyzers to measure the particle environment and surface potential monitors to track differential charging between various materials and vehicle ground. While typical RMS error analysis methods provide a sense of the models overall abilities, they do not specifically address physical situations critical to operations, i.e., how well does the model specify when a high differential charging state is probable. In this validation study, differential charging states observed by DSCS are used to determine several threshold fluxes for the associated 20-50keV electrons and joint probability distributions are constructed to determine Hit, Miss, and False Alarm rates for the models. An MSM run covering the two and one-half year interval is performed using the minimum required input parameter set, consisting of only the magnetic activity index Kp, in order to statistically examine the model's seasonal and yearly performance. In addition, the relative merits of the input parameter, i.e., Kp, Dst, the equatorward boundary of diffuse aurora at midnight, cross-polar cap potential, solar wind density and velocity, and interplanetary magnetic field values, are evaluated as drivers of shorter model runs of 100 d each. In an effort to develop operational tools that can address spacecraft charging issues, we also identify temporal features in the model output that can be directly linked to input parameter variations and model boundary conditions. All model output is interpreted using the full three-dimensional, dipole tilt-dependent algorithms currently in

  14. Co-administration of morphine and gabapentin leads to dose dependent synergistic effects in a rat model of postoperative pain

    DEFF Research Database (Denmark)

    Papathanasiou, Theodoros; Juul, Rasmus Vestergaard; Heegaard, Anne-Marie

    2016-01-01

    dose combinations and investigate whether co-administration leads to synergistic effects in a preclinical model of postoperative pain. The pharmacodynamic effects of morphine (1, 3 and 7 mg/kg), gabapentin (10, 30 and 100 mg/kg) or their combination (9 combinations in total) were evaluated in the rat...... plantar incision model using an electronic von Frey device. The percentage of maximum possible effect (%MPE) and the area under the response curve (AUC) were used for evaluation of the antihyperalgesic effects of the drugs. Identification of synergistic interactions was based on Loewe additivity response...... surface analyses. The combination of morphine and gabapentin resulted in synergistic antihyperalgesic effects in a preclinical model of postoperative pain. The synergistic interactions were found to be dose dependent and the increase in observed response compared to the theoretical additive response...

  15. Endometriose: modelo experimental em ratas Endometriosis: experimental model in rats

    Directory of Open Access Journals (Sweden)

    Eduardo Schor

    1999-06-01

    that the free portion of the endometrium was directed towards the lumen of the abdominal cavity. After 21 days the animals were again operated to observe the size of the implants and to remove the ectopic endometrium for microscopic analysis. Results: we macroscopically observed a significant growth of the endometrial implants. Microscopic examination showed presence of glandular epithelium and stroma similar to topic epithelium. Conclusion: this model reproduces endometriosis in the female rat allowing a better study of this pathology, mainly the action of drugs on these implants.

  16. Mesenchymal stem cells in renal function recovery after acute kidney injury: use of a differentiating agent in a rat model.

    Science.gov (United States)

    La Manna, Gaetano; Bianchi, Francesca; Cappuccilli, Maria; Cenacchi, Giovanna; Tarantino, Lucia; Pasquinelli, Gianandrea; Valente, Sabrina; Della Bella, Elena; Cantoni, Silvia; Claudia, Cavallini; Neri, Flavia; Tsivian, Matvey; Nardo, Bruno; Ventura, Carlo; Stefoni, Sergio

    2011-01-01

    Acute kidney injury (AKI) is a major health care condition with limited current treatment options. Within this context, stem cells may provide a clinical approach for AKI. Moreover, a synthetic compound previously developed, hyaluronan monoesters with butyric acid (HB), able to induce metanephric differentiation, formation of capillary-like structures, and secretion of angiogenic cytokines, was tested in vitro. Thereafter, we investigated the effects of human mesenchymal stem cells from fetal membranes (FMhMSCs), both treated and untreated with HB, after induction of ischemic AKI in a rat model. At reperfusion following 45-min clamping of renal pedicles, each rat was randomly assigned to one of four groups: CTR, PBS, MSC, and MSC-HB. Renal function at 1, 3, 5, and 7 days was assessed. Histological samples were analyzed by light and electron microscopy and renal injury was graded. Cytokine analysis on serum samples was performed. FMhMSCs induced an accelerated renal functional recovery, demonstrated by biochemical parameters and confirmed by histology showing that histopathological alterations associated with ischemic injury were less severe in cell-treated kidneys. HB-treated rats showed a minor degree of inflammation, both at cytokine and TEM analyses. Better functional and morphological recovery were not associated to stem cells' regenerative processes, but possibly suggest paracrine effects on microenvironment that induce retrieval of renal damaged tissues. These results suggest that FMhMSCs could be useful in the treatment of AKI and the utilization of synthetic compounds could enhance the recovery induction ability of cells.

  17. Metabolic alterations of toxic and nonessential elements by the treatment of Sempervivum tectorum extract in a hyperlipidemic rat model.

    Science.gov (United States)

    Szentmihályi, Klára; Fehér, Erzsébet; Vinkler, Péter; Kéry, Agnes; Blázovics, Anna

    2004-01-01

    A hyperlipidemic rat model was used to examine the therapeutic effect of Sempervivum tectorum plant extract on the metabolic alterations of Al, As, B, Ba, Cd, Hg, Ni, Pb, and Ti in the liver and bile. Hyperlipidemia was produced by lipogenic diet and alcohol and verified by morphological investigation of the liver with the aid of light and an electron microscope. Element concentration in the liver and bile were determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The concentration values in the liver higher than the detection limit (Al, Ba, Ni, Ti) were unambiguous. Significant differences were found for the four groups at p < 0.05 level (ANOVA). A significant difference was observed between Al and B concentration in the bile fluids of the 4 groups (p < 0.05). The excretion of Al and Ti into the bile fluid increased significantly (p < 0.05). Following the administration of S. tectorum extract to rats with hyperlipidemia, the excretion of Al, B and Ba increased, whereas the excretion of Ti decreased significantly (p < 0.05). The favorable action of the extract (protecting the liver in hyperlipidemic rats) was verified by morphological studies, and its detoxicating property was shown by the elimination of Al, Ba, Ni, and Ti from the liver.

  18. A disposition kinetic study of Tramadol in bile duct ligated rats in perfused rat liver model.

    Science.gov (United States)

    Esmaeili, Zohre; Mohammadi, Saeid; Nezami, Alireza; Rouini, Mohammad Reza; Ardakani, Yalda Hosseinzadeh; Lavasani, Hoda; Ghazi-Khansari, Mahmoud

    2017-07-01

    Tramadol hydrochloride is a centrally acting synthetic opioid analgesic drug and is used to treat chronic pain. In this study, the effects of Bile Duct Ligation (BDL) on the pharmacokinetics of tramadol in a liver recirculating perfusion system of male rats were used. Twenty-four Wistar male rats were randomly divided into four groups: control, sham and two weeks BDL and four weeks BDL. Serum levels of liver enzymes were measured before perfusion and the pharmacokinetics of tramadol was evaluated by using liver recirculating perfusion system. Tramadol and metabolites concentrations were determined by HPLC-FL. The sharp increase in liver enzymes level in both BDL groups was observed and significant changes were also observed in liver weight and volume. Tramadol metabolites concentration significantly decreased compared with the control and sham group (Pbile duct diseases and the dose of tramadol should be accordingly adjusted. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  19. Modeling a Miniaturized Scanning Electron Microscope Focusing Column - Lessons Learned in Electron Optics Simulation

    Science.gov (United States)

    Loyd, Jody; Gregory, Don; Gaskin, Jessica

    2016-01-01

    This presentation discusses work done to assess the design of a focusing column in a miniaturized Scanning Electron Microscope (SEM) developed at the NASA Marshall Space Flight Center (MSFC) for use in-situ on the Moon-in particular for mineralogical analysis. The MSFC beam column design uses purely electrostatic fields for focusing, because of the severe constraints on mass and electrical power consumption imposed by the goals of lunar exploration and of spaceflight in general. The resolution of an SEM ultimately depends on the size of the focused spot of the scanning beam probe, for which the stated goal here is a diameter of 10 nanometers. Optical aberrations are the main challenge to this performance goal, because they blur the ideal geometrical optical image of the electron source, effectively widening the ideal spot size of the beam probe. In the present work the optical aberrations of the mini SEM focusing column were assessed using direct tracing of non-paraxial rays, as opposed to mathematical estimates of aberrations based on paraxial ray-traces. The geometrical ray-tracing employed here is completely analogous to ray-tracing as conventionally understood in the realm of photon optics, with the major difference being that in electron optics the lens is simply a smoothly varying electric field in vacuum, formed by precisely machined electrodes. Ray-tracing in this context, therefore, relies upon a model of the electrostatic field inside the focusing column to provide the mathematical description of the "lens" being traced. This work relied fundamentally on the boundary element method (BEM) for this electric field model. In carrying out this research the authors discovered that higher accuracy in the field model was essential if aberrations were to be reliably assessed using direct ray-tracing. This led to some work in testing alternative techniques for modeling the electrostatic field. Ultimately, the necessary accuracy was attained using a BEM

  20. Characterization of dystrophin deficient rats: a new model for Duchenne muscular dystrophy.

    Science.gov (United States)

    Larcher, Thibaut; Lafoux, Aude; Tesson, Laurent; Remy, Séverine; Thepenier, Virginie; François, Virginie; Le Guiner, Caroline; Goubin, Helicia; Dutilleul, Maéva; Guigand, Lydie; Toumaniantz, Gilles; De Cian, Anne; Boix, Charlotte; Renaud, Jean-Baptiste; Cherel, Yan; Giovannangeli, Carine; Concordet, Jean-Paul; Anegon, Ignacio; Huchet, Corinne

    2014-01-01

    A few animal models of Duchenne muscular dystrophy (DMD) are available, large ones such as pigs or dogs being expensive and difficult to handle. Mdx (X-linked muscular dystrophy) mice only partially mimic the human disease, with limited chronic muscular lesions and muscle weakness. Their small size also imposes limitations on analyses. A rat model could represent a useful alternative since rats are small animals but 10 times bigger than mice and could better reflect the lesions and functional abnormalities observed in DMD patients. Two lines of Dmd mutated-rats (Dmdmdx) were generated using TALENs targeting exon 23. Muscles of animals of both lines showed undetectable levels of dystrophin by western blot and less than 5% of dystrophin positive fibers by immunohistochemistry. At 3 months, limb and diaphragm muscles from Dmdmdx rats displayed severe necrosis and regeneration. At 7 months, these muscles also showed severe fibrosis and some adipose tissue infiltration. Dmdmdx rats showed significant reduction in muscle strength and a decrease in spontaneous motor activity. Furthermore, heart morphology was indicative of dilated cardiomyopathy associated histologically with necrotic and fibrotic changes. Echocardiography showed significant concentric remodeling and alteration of diastolic function. In conclusion, Dmdmdx rats represent a new faithful small animal model of DMD.

  1. Changes of cerebral contents of neuropeptides in rat models of multiple ischemic dementia (MID)

    International Nuclear Information System (INIS)

    Zheng Xianghong; Guo Jingcai; Song Changyi; Wang Shejiao; Chen Wei

    2005-01-01

    Objective: To investigate the significance of changes of cerebral contents of the neuropeptides somatostatin (SS), arginine vasopressin (AVP) and substance P in rat models of MID. Methods: The rat models consisted of 15 rats undergoing intracarotid injection of autogenous thrombus powder. Another group of 15 rats undergoing sham operation served as controls. Learning and memory ability in these rats was assessed with daily passive avoidance task testing for 10 consecutive days. The animals were sacrificed on 30d and contents of the neuropeptides in tissue homogenate from different areas of brain (frontal cortex, temporal cortex, hippocampus, thalamus and corpus striatum) were measured with (RIA). Results: On the first day of passive avoidance task testing, the frequency of errors in the MID group and the control group was about the same. From the third day on, the frequency of errors in the MID group was significantly higher than that in the control group (P<0.05). The neuropeptides contents of all these cerebral areas in the MID group were significantly higher than those in the control group (P<0.05 or P<0.01) with the only exception of the contents of substance P in thalamus (no significant difference between the contents in the two groups). Conclusion: The impairment of learning and memory in rat models with MID was possibly related to the lowered contents of SS, AVP and substance P in the brain tissue. (authors)

  2. Additive effect of mesenchymal stem cells and defibrotide in an arterial rat thrombosis model.

    Science.gov (United States)

    Dilli, Dilek; Kılıç, Emine; Yumuşak, Nihat; Beken, Serdar; Uçkan Çetinkaya, Duygu; Karabulut, Ramazan; Zenciroğlu, Ayşegu L

    2017-06-01

    In this study, we aimed to investigate the additive effect of mesenchymal stem cells (MSC) and defibrotide (DFT) in a rat model of femoral arterial thrombosis. Thirty Sprague Dawley rats were included. An arterial thrombosis model by ferric chloride (FeCl3) was developed in the left femoral artery. The rats were equally assigned to 5 groups: Group 1-Sham-operated (without arterial injury); Group 2-Phosphate buffered saline (PBS) injected; Group 3-MSC; Group 4-DFT; Group 5-MSC + DFT. All had two intraperitoneal injections of 0.5 ml: the 1st injection was 4 h after the procedure and the 2nd one 48 h after the 1st injection. The rats were sacrificed 7 days after the 2nd injection. Although the use of human bone marrow-derived (hBM) hBM-MSC or DFT alone enabled partial resolution of the thrombus, combining them resulted in near-complete resolution. Neovascularization was two-fold better in hBM-MSC + DFT treated rats (11.6 ± 2.4 channels) compared with the hBM-MSC (3.8 ± 2.7 channels) and DFT groups (5.5 ± 1.8 channels) (P < 0.0001 and P= 0.002, respectively). The combined use of hBM-MSC and DFT in a rat model of arterial thrombosis showed additive effect resulting in near-complete resolution of the thrombus.

  3. The Dismantling of the Japanese Model in Consumer Electronics

    DEFF Research Database (Denmark)

    Frøslev Christensen, Jens; Holm Olesen, Michael; Kjær, Jonas

    This paper addresses an issue of great importance for the future organization of the consumerelectronics industry: the "battle" of control over component-based digitization. We are now witnessing the dismantling of the Japanese Model that has prevailed in consumer electronicsover the past 30 years....... Specialized and large-scale component suppliers have taken the lead inmost component-based innovations and have obtained increasingly powerful positions in thevalue chain of consumer electronics. This paper provides an in-depth study of the strategic andstructural ramifications of one such component...... technology. Aframework is developed to explain the reluctance of most of the large consumer electronicsgiants in developing/adopting this new technology.Key words: Consumer electronics, Industrial dynamics, Open InnovationJEL Codes: L6, L68, O32...

  4. Electronic Commerce Success Model: A Search for Multiple Criteria

    Directory of Open Access Journals (Sweden)

    Didi Achjari

    2004-01-01

    Full Text Available The current study attempts to develop and examine framework of e-commerce success. In order to obtain comprehensive and robust measures, the framework accomodates key factors that are identified in the literature concerning the success of electronic commerce. The structural model comprises of four exogenous variables (Internal Driver, Internal Impediment, External Driver and Exgternal Impediment and one endogenous variable (Electornic Commerce Success eith 24 observed variables. The study that was administered within large Australian companies using questionaire survey concluded that benefits for both internal organization and external parties from the use of e-commerce were the main factor tro predict perceived and/or expected success of electronic commerce.

  5. Electron distribution in polar heterojunctions within a realistic model

    Energy Technology Data Exchange (ETDEWEB)

    Tien, Nguyen Thanh, E-mail: thanhtienctu@gmail.com [College of Natural Science, Can Tho University, 3-2 Road, Can Tho City (Viet Nam); Thao, Dinh Nhu [Center for Theoretical and Computational Physics, College of Education, Hue University, 34 Le Loi Street, Hue City (Viet Nam); Thao, Pham Thi Bich [College of Natural Science, Can Tho University, 3-2 Road, Can Tho City (Viet Nam); Quang, Doan Nhat [Institute of Physics, Vietnamese Academy of Science and Technology, 10 Dao Tan Street, Hanoi (Viet Nam)

    2015-12-15

    We present a theoretical study of the electron distribution, i.e., two-dimensional electron gas (2DEG) in polar heterojunctions (HJs) within a realistic model. The 2DEG is confined along the growth direction by a triangular quantum well with a finite potential barrier and a bent band figured by all confinement sources. Therein, interface polarization charges take a double role: they induce a confining potential and, furthermore, they can make some change in other confinements, e.g., in the Hartree potential from ionized impurities and 2DEG. Confinement by positive interface polarization charges is necessary for the ground state of 2DEG existing at a high sheet density. The 2DEG bulk density is found to be increased in the barrier, so that the scattering occurring in this layer (from interface polarization charges and alloy disorder) becomes paramount in a polar modulation-doped HJ.

  6. Electron electric dipole moment in Inverse Seesaw models

    Energy Technology Data Exchange (ETDEWEB)

    Abada, Asmaa; Toma, Takashi [Laboratoire de Physique Théorique, CNRS, University Paris-Sud, Université Paris-Saclay,91405 Orsay (France)

    2016-08-11

    We consider the contribution of sterile neutrinos to the electric dipole moment of charged leptons in the most minimal realisation of the Inverse Seesaw mechanism, in which the Standard Model is extended by two right-handed neutrinos and two sterile fermion states. Our study shows that the two pairs of (heavy) pseudo-Dirac mass eigenstates can give significant contributions to the electron electric dipole moment, lying close to future experimental sensitivity if their masses are above the electroweak scale. The major contribution comes from two-loop diagrams with pseudo-Dirac neutrino states running in the loops. In our analysis we further discuss the possibility of having a successful leptogenesis in this framework, compatible with a large electron electric dipole moment.

  7. Electron electric dipole moment in Inverse Seesaw models

    International Nuclear Information System (INIS)

    Abada, Asmaa; Toma, Takashi

    2016-01-01

    We consider the contribution of sterile neutrinos to the electric dipole moment of charged leptons in the most minimal realisation of the Inverse Seesaw mechanism, in which the Standard Model is extended by two right-handed neutrinos and two sterile fermion states. Our study shows that the two pairs of (heavy) pseudo-Dirac mass eigenstates can give significant contributions to the electron electric dipole moment, lying close to future experimental sensitivity if their masses are above the electroweak scale. The major contribution comes from two-loop diagrams with pseudo-Dirac neutrino states running in the loops. In our analysis we further discuss the possibility of having a successful leptogenesis in this framework, compatible with a large electron electric dipole moment.

  8. Characterization of Diabetic Neuropathy in the Zucker Diabetic Sprague-Dawley Rat: A New Animal Model for Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Eric P. Davidson

    2014-01-01

    Full Text Available Recently a new rat model for type 2 diabetes the Zucker diabetic Sprague-Dawley (ZDSD/Pco was created. In this study we sought to characterize the development of diabetic neuropathy in ZDSD rats using age-matched Sprague-Dawley rats as a control. Rats were examined at 34 weeks of age 12 weeks after the onset of hyperglycemia in ZDSD rats. At this time ZDSD rats were severely insulin resistant with slowing of both motor and sensory nerve conduction velocities. ZDSD rats also had fatty livers, elevated serum free fatty acids, triglycerides, and cholesterol, and elevated sciatic nerve nitrotyrosine levels. The corneas of ZDSD rats exhibited a decrease in subbasal epithelial corneal nerves and sensitivity. ZDSD rats were hypoalgesic but intraepidermal nerve fibers in the skin of the hindpaw were normal compared to Sprague-Dawley rats. However, the number of Langerhans cells was decreased. Vascular reactivity of epineurial arterioles, blood vessels that provide circulation to the sciatic nerve, to acetylcholine and calcitonin gene-related peptide was impaired in ZDSD rats. These data indicate that ZDSD rats develop many of the neural complications associated with type 2 diabetes and are a good animal model for preclinical investigations of drug development for diabetic neuropathy.

  9. [Study on the oxidative stress in the ovaries of a rat model of polycystic ovary].

    Science.gov (United States)

    Gong, Jin; Wu, Dong-bo; Zhang, Lan-lan; Li, Jia; Zhao, Xing; Zhang, Dan

    2015-03-01

    To establish a pathological animal model of polycystic ovary (PCO) by letrozole in rats. Investigate whether PCO were mediated by the effect of oxidative stress by measuring oxidative stress levels in this cohort of rats with PCO, and proceed a new way of treatment for polycystic ovary syndrom (PCOS). 90 SD female rats aged 6 weeks were randomly divided into two groups, including a control group of 45 rats that received vehicle only [19% aqueous solution of carboxmethlycellulose (CMC), 1 mL/d] once daily orally (p.o.), and an experimental group of 45 rats, which were administered letrozole at concentrations of 1 mg/kg p.o. dissolved in 1% CMC (1 mL/d) once daily. The treatment period was 28 d. During this period, vaginal smears were collected daily for estrus cycle determination and body masses were measured every 7 d. On the day subsequent to the last letrozole dose administration, rats were killed; Uteri and ovaries were then excised and weighed for the calculation of organ indexes. Serum hormone levels, SHBG and histologic changes in the ovaries were examined. Then testosterone free index (FAD) was calculated. Oxidant status was evaluated by determination of ovarian total oxidant status (TOS), malondialdehyde (MDA) concentration and intracellular reactive oxygen species (ROS) level, while antioxidant status was evaluated by determination of total antioxidant status (TAS) and superoxide dismutase (SOD) concentration. Vaginal smear test showed the estrus cycle began to disappear from day 12 to day 15. A statistically significant difference in growth curves, ovarian weights, uterine weights and organ indexes between the groups were also observed. In rats with PCO serum testosterone (T), follicle-stimulating hormone (FSH) concentrations and free androgen index (FADI) were significantly increased compared with the control group (rats without PCO). However, rats with PCO had decreased levels of estrogen (E2), luteinizing hormone (LH), and progesterone (P) compared

  10. An Electron microscopic, radioautographic study of protein synthesis in vitro in the palatal mucosa of the rat

    International Nuclear Information System (INIS)

    Kim, Hyun Joo

    1987-01-01

    The incorporation of 3H-proline by epithelial and connective tissue elements of rat palatal mucosa was studied in order to investigate the relative levels of protein synthesis by the epithelium and underlying connective tissue cells. Following a sixty minutes incorporation of the radioactive tracer in vitro, it was found that the suprabasal cells had most grains per unit area. Furthermore, the grains were more concentrated over the cytoplasm than the nucleus. This was in contrast with the labeling of basal cells which had twice as many grains over the nucleoplasm than that over the cytoplasm. In intermediate cells; i.e., the spinous layer, the number of silver grains per unit area was decreased from that of the surprabasal cells. In area where desmosomes were more prominent, many grains were in touch with such desmosomes. However, the labeling appeared to be reduced as soon as the cells became flattened. Moreover, the epidermal keratohyalin granules were relatively free of grains. Except for certain intercellular surfaces the keratinized cells were generally free of grains. On the connective tissue side, silver grains were primarily localized over the fibroblasts with occasional grains over collagenous fibers were found over palatal muscle cells, neural elements and so on. Most grains over collagenous fibers were found in relation to mature collagen fibrils. Thus, protein synthesis in isolated mucosas of the rat palate apparent take place both in epithelial and connective elements. There were no apparent tissue alterations caused by the in vitro incorporation procedure utilized under conditions of this study. Key words: Electron microscopy, Radioautography, Protein synthesis, In vitro, Rat, Palate, 3H-poline

  11. The Effects of Methylphenidate on Goal-Directed Behavior in a Rat Model of ADHD

    Directory of Open Access Journals (Sweden)

    Joman Y. Natsheh

    2015-11-01

    Full Text Available Although attentional and motor alterations in Attention Deficit Hyperactivity Disorder (ADHD have been well characterized, less is known about how this disorder impacts goal-directed behavior. To investigate whether there is a misbalance between goal-directed and habitual behaviors in an animal model of ADHD, we tested adult [P75-P105] Spontaneously Hypertensive Rats (SHR (ADHD rat model and Wistar-Kyoto rats (WKY, the normotensive control strain, on an instrumental conditioning paradigm with two phases: a free-operant training phase in which rats separately acquired two distinct action-outcome contingencies, and a choice test conducted in extinction prior to which one of the food outcomes was devalued through specific satiety. To assess the effects of Methylphenidate, a commonly used ADHD medication, on goal-directed behavior, we injected rats with either Methylphenidate or saline prior to the choice test. Both rat strains acquired an instrumental response, with SHR responding at greater rates over the course of training. During the choice test WKY demonstrated goal-directed behavior, responding more frequently on the lever that delivered, during training, the still-valued outcome. In contrast, SHR showed no goal-directed behavior, responding equally on both levers. However, methylphenidate administration prior to the choice test restored goal-directed behavior in SHR, and disrupted this behavior in WKY rats. This study provides the first experimental evidence for selective impairment in goal-directed behavior in rat models of ADHD, and how methylphenidate acts differently on SHR and WKY animals to restore or impair this behavior, respectively.

  12. Effects of synbiotics on intestinal mucosal barrier in rat model

    Directory of Open Access Journals (Sweden)

    Zhigang Xue

    2017-06-01

    Conclusions: Probiotics can improve the concentration of colonic probiotics, while synbiotics can improve probiotics concentration and mucosa thickness in colon, decrease L/M ratio and bacterial translocation. Synbiotics shows more protective effects on intestinal mucosal barrier in rats after cecectomy and gastrostomy and the intervention of specific antibiotics.

  13. The F8(-/-) rat as a model of hemophilic arthropathy

    DEFF Research Database (Denmark)

    Christensen, Kristine Rothaus; Roepstorff, K.; Wiinberg, B.

    2016-01-01

    . Methods Wild-type and F8(-/-) rats were treated with vehicle or recombinant human factor VIII (rhFVIII) prior to a needle-induced joint bleed. Joint swelling was measured prior to injury, the following 7 days and upon euthanasia. Histologic sections of the joint were stained, and athropathic changes...

  14. Opioid Receptors Blockade Modulates Apoptosis in a Rat Model of ...

    African Journals Online (AJOL)

    inflammation characterized by replacement of liver tissue by ... Materials and Methods: Cirrhosis was induced in rats by bile duct ligation .... treated with deoxyribonucleic acid labeling solution containing ... binding was inhibited using non-immune serum. .... studies considering the increased level of tumor necrosis factor-α.

  15. The Fischer 344 rat as a model of presbycusis

    Czech Academy of Sciences Publication Activity Database

    Syka, Josef

    2010-01-01

    Roč. 264, 1-2 (2010), s. 70-78 ISSN 0378-5955 R&D Projects: GA ČR GA309/07/1336; GA MŠk(CZ) LC554 Institutional research plan: CEZ:AV0Z50390703 Keywords : Rat * Fischer 344 * Presbycusis Subject RIV: FH - Neurology Impact factor: 2.428, year: 2010

  16. Cellular Biochemistry and Cytogenetics in a Rat Lung Tumor Model

    Science.gov (United States)

    1984-10-01

    lung tumor system the specific aims are: 1. To conduct studies of the effect of 3-methylchlanthrene (MCA) on DNA synthesis and cell proliferation in...alkylation of nucleic acids of the rat by N-methyl-N- nitrosourea , dimethylnitrosamine, dimethylsulfate, and methylmethanesulfonate. Biochem. J. 110:39-47

  17. Neuroprotective effect corilagin in spinal cord injury rat model by ...

    African Journals Online (AJOL)

    Background: Neurological functions get altered in a patient suffering from spinal cord injury (SCI). Present study evaluates the neuroprotective effect of corilagin in spinal cord injury rats by inhibiting nuclear factor-kappa B (NF-κB), inflammatory mediators and apoptosis. Materials and method: Spinal cord injury was ...

  18. Electron reactions in model liquids and biological systems

    International Nuclear Information System (INIS)

    Bakale, G.; Gregg, E.C.

    1982-01-01

    Progress is reported in the following studies: (1) Field-dependent electron attachment; (2) Dependence of electron attachment rate on electron-acceptor dipole moment; (3) Electron attachment in i-octane/TMS mixtures; (4) Electron attachment/detachment equilibria; (5) Electron attachment to reversed micelles; (6) Electron attachment to chemical carcinogens; (7) Radiation-induced bacterial mutagenesis; and (8) Bacterial mutagenicity of nitrobenzene derivatives. 14 references

  19. Theoretical modeling of electron mobility in superfluid {sup 4}He

    Energy Technology Data Exchange (ETDEWEB)

    Aitken, Frédéric; Bonifaci, Nelly [G2ELab-GreEn-ER, Equipe MDE, 21 Avenue des Martyrs, CS 90624, 38031 Grenoble Cedex 1 (France); Haeften, Klaus von [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Eloranta, Jussi, E-mail: Jussi.Eloranta@csun.edu [Department of Chemistry and Biochemistry, California State University at Northridge, 18111 Nordhoff St., Northridge, California 91330 (United States)

    2016-07-28

    The Orsay-Trento bosonic density functional theory model is extended to include dissipation due to the viscous response of superfluid {sup 4}He present at finite temperatures. The viscous functional is derived from the Navier-Stokes equation by using the Madelung transformation and includes the contribution of interfacial viscous response present at the gas-liquid boundaries. This contribution was obtained by calibrating the model against the experimentally determined electron mobilities from 1.2 K to 2.1 K along the saturated vapor pressure line, where the viscous response is dominated by thermal rotons. The temperature dependence of ion mobility was calculated for several different solvation cavity sizes and the data are rationalized in the context of roton scattering and Stokes limited mobility models. Results are compared to the experimentally observed “exotic ion” data, which provides estimates for the corresponding bubble sizes in the liquid. Possible sources of such ions are briefly discussed.

  20. Modeling of electron time variations in the radiation belts

    International Nuclear Information System (INIS)

    Chan, K.W.; Teague, M.J.; Schofield, N.J.; Vette, J.I.

    1979-01-01

    A review of the temporal variation in the trapped electron population of the inner and outer radiation zones is presented. Techniques presently used for modeling these zones are discussed and their deficiencies identified. An intermediate region is indicated between the zones in which the present modeling techniques are inadequate due to the magnitude and frequency of magnetic storms. Future trends are examined, and it is suggested that modeling of individual magnetic storms may be required in certain L bands. An analysis of seven magnetic storms is presented, establishing the independence of the depletion time of the storm flux and the storm magnitude. Provisional correlation between the storm magnitude and the Dst index is demonstrated

  1. Effects of gamma radiation on hard dental tissues of albino rats using scanning electron microscope - Part 1

    Science.gov (United States)

    El-Faramawy, Nabil; Ameen, Reham; El-Haddad, Khaled; Maghraby, Ahmed; El-Zainy, Medhat

    2011-12-01

    In the present study, 40 adult male albino rats were used to study the effect of gamma radiation on the hard dental tissues (enamel surface, dentinal tubules and the cementum surface). The rats were irradiated at 0.2, 0.5, 1.0, 2.0, 4.0 and 6.0 Gy gamma doses. The effects of irradiated hard dental tissues samples were investigated using a scanning electron microscope. For doses up to 0.5 Gy, there was no evidence of the existence of cracks on the enamel surface. With 1 Gy irradiation dose, cracks were clearly observed with localized erosive areas. At 2 Gy irradiation dose, the enamel showed morphological alterations as disturbed prismatic and interprismatic areas. An increase in dentinal tubules diameter and a contemporary inter-tubular dentine volume decrease were observed with higher irradiation dose. Concerning cementum, low doses,<0.5 Gy, showed surface irregularities and with increase in the irradiation dose to≥1 Gy, noticeable surface irregularities and erosive areas with decrease in Sharpey's fiber sites were observed. These observations could shed light on the hazardous effects of irradiation fields to the functioning of the human teeth.

  2. Modelling of electron transport and of sawtooth activity in tokamaks

    International Nuclear Information System (INIS)

    Angioni, C.

    2001-10-01

    Transport phenomena in tokamak plasmas strongly limit the particle and energy confinement and represent a crucial obstacle to controlled thermonuclear fusion. Within the vast framework of transport studies, three topics have been tackled in the present thesis: first, the computation of neoclassical transport coefficients for general axisymmetric equilibria and arbitrary collisionality regime; second, the analysis of the electron temperature behaviour and transport modelling of plasma discharges in the Tokamak a configuration Variable (TCV); third, the modelling and simulation of the sawtooth activity with different plasma heating conditions. The work dedicated to neoclassical theory has been undertaken in order to first analytically identify a set of equations suited for implementation in existing Fokker-Planck codes. Modifications of these codes enabled us to compute the neoclassical transport coefficients considering different realistic magnetic equilibrium configurations and covering a large range of variation of three key parameters: aspect ratio, collisionality, and effective charge number. A comparison of the numerical results with an analytical limit has permitted the identification of two expressions for the trapped particle fraction, capable of encapsulating the geometrical effects and thus enabling each transport coefficient to be fitted with a single analytical function. This has allowed us to provide simple analytical formulae for all the neoclassical transport coefficients valid for arbitrary aspect ratio and collisionality in general realistic geometry. This work is particularly useful for a correct evaluation of the neoclassical contribution in tokamak scenarios with large bootstrap cur- rent fraction, or improved confinement regimes with low anomalous transport and for the determination of the plasma current density profile, since the plasma conductivity is usually assumed neoclassical. These results have been included in the plasma transport code

  3. The effect of high energy electron irradiation on blood-brain barrier permeability to haloperidol and stobadin in rats

    Energy Technology Data Exchange (ETDEWEB)

    Trnovec, T; Kallay, Z [Komenskeho Univ., Bratislava (Czechoslovakia). Inst. of Preventive and Clinical Medicine; Volenec, K [Karlova Univ., Hradec Kralove (Czechoslovakia). Lekarska Fakulta; Bezek, S; Durisova, M; Scasnar, V; Kubu, M [Slovenska Akademia Vied, Bratislava (Czechoslovakia). Ustav Experimentalnej Farmakologie; Svoboda, V [Medical Academy J.E. Purkyne, Hradec Kralove (Czechoslovakia)

    1991-10-01

    The heads of rats were irradiated by 4 MeV electrons in doses 90, 180, and 360 Gy. The observed times of deaths ranged 120-600, 60-420, and 150-370 min after 90, 180, and 360 Gy, respectively. A dose dependent decrease of the brain uptake index of haloperidol was observed 1 and 3 h post radiation. On the other hand an increased brain uptake index was found for stobadin after head irradiation with doses of 180 and 360 Gy. Regional cerebral blood flow, blood pressure, and heart rate were not significantly altered in the period following irradiation with 180 Gy. The observed changes in blood-brain barrier (BBB) permeability seem to be the result of the damaged function of morphological structures forming the BBB rather than altered regional blood flow. (orig.).

  4. Metabolic Disorders and Diabetic Complications in Spontaneously Diabetic Torii Leprfa Rat: A New Obese Type 2 Diabetic Model

    Directory of Open Access Journals (Sweden)

    Yusuke Kemmochi

    2013-01-01

    Full Text Available Spontaneously Diabetic Torii Leprfa (SDT fatty rat, established by introducing the fa allele of the Zucker fatty rat into SDT rat genome, is a new model of obese type 2 diabetes. Both male and female SDT fatty rats show overt obesity, and hyperglycemia and hyperlipidemia are observed at a young age as compared with SDT rats. With early incidence of diabetes mellitus, diabetic complications, such as nephropathy, retinopathy, and neuropathy, in SDT fatty rats were seen at younger ages compared to those in the SDT rats. In this paper, we overview pathophysiological features in SDT fatty rats and also describe new insights regarding the hematology, blood pressure, renal complications, and sexual dysfunction. The SDT fatty rats showed an increase of leukocytes, especially the monocyte count, prominent hypertension associated with salt drinking, end-stage renal disease with aging, and hypogonadism. Unlike other diabetic models, the characteristic of SDT fatty rat is to present an incidence of diabetes in females, hypertension, and retinopathy. SDT fatty rat is a useful model for analysis of various metabolic disorders and the evaluation of drugs related to metabolic disease.

  5. Neuromyelitis optica study model based on chronic infusion of autoantibodies in rat cerebrospinal fluid.

    Science.gov (United States)

    Marignier, R; Ruiz, A; Cavagna, S; Nicole, A; Watrin, C; Touret, M; Parrot, S; Malleret, G; Peyron, C; Benetollo, C; Auvergnon, N; Vukusic, S; Giraudon, P

    2016-05-18

    Devic's neuromyelitis optica (NMO) is an autoimmune astrocytopathy, associated with central nervous system inflammation, demyelination, and neuronal injury. Several studies confirmed that autoantibodies directed against aquaporin-4 (AQP4-IgG) are relevant in the pathogenesis of NMO, mainly through complement-dependent toxicity leading to astrocyte death. However, the effect of the autoantibody per se and the exact role of intrathecal AQP4-IgG are still controversial. To explore the intrinsic effect of intrathecal AQP4-IgG, independent from additional inflammatory effector mechanisms, and to evaluate its clinical impact, we developed a new animal model, based on a prolonged infusion of purified immunoglobulins from NMO patient (IgG(AQP4+), NMO-rat) and healthy individual as control (Control-rat) in the cerebrospinal fluid (CSF) of live rats. We showed that CSF infusion of purified immunoglobulins led to diffusion in the brain, spinal cord, and optic nerves, the targeted structures in NMO. This was associated with astrocyte alteration in NMO-rats characterized by loss of aquaporin-4 expression in the spinal cord and the optic nerves compared to the Control-rats (p = 0.001 and p = 0.02, respectively). In addition, glutamate uptake tested on vigil rats was dramatically reduced in NMO-rats (p = 0.001) suggesting that astrocytopathy occurred in response to AQP4-IgG diffusion. In parallel, myelin was altered, as shown by the decrease of myelin basic protein staining by up to 46 and 22 % in the gray and white matter of the NMO-rats spinal cord, respectively (p = 0.03). Loss of neurofilament positive axons in NMO-rats (p = 0.003) revealed alteration of axonal integrity. Then, we investigated the clinical consequences of such alterations on the motor behavior of the NMO-rats. In a rotarod test, NMO-rats performance was lower compared to the controls (p = 0.0182). AQP4 expression, and myelin and axonal integrity were preserved in AQP4-Ig

  6. Radiation-induced hydronephrosis in the rat: a new experimental model

    International Nuclear Information System (INIS)

    Knowles, J.F.

    1985-01-01

    An experimental model for investigating the effects of localized X-irradiation on a single ureter or the bladder trigone in rats is described. Obstruction of the urinary tract in the irradiated region gives rise to hydroureter and hydronephrosis and the development of these, as detected urographically, gives a clear-cut end point. After irradiation of the ureter with a single dose of 37.4 gy many rats died of gut lesions but after 23.4 Gy only one such death occurred while 14 of 16 rats developed hydronephrosis. Irradiation of the bladder trigone was not associated with intercurrent deaths, even after 40 Gy, and after 25 Gy 9 of 11 rats developed hydronephrosis. (author)

  7. Resveratrol Reduces the Incidence of Portal Vein System Thrombosis after Splenectomy in a Rat Fibrosis Model

    Science.gov (United States)

    Xu, Meng; Xue, Wanli; Ma, Zhenhua; Bai, Jigang

    2016-01-01

    Purpose. To investigate the preventive effect of resveratrol (RES) on the formation of portal vein system thrombosis (PVST) in a rat fibrosis model. Methods. A total of 64 male SD rats, weighing 200–300 g, were divided into five groups: Sham operation, Splenectomy I, Splenectomy II, RES, and low molecular weight heparin (LMWH), with the former two groups as nonfibrosis controls. Blood samples were subjected to biochemical assays. Platelet apoptosis was measured by flow cytometry. All rats were euthanized for PVST detection one week after operation. Results. No PVST occurred in nonfibrosis controls. Compared to Splenectomy II, the incidences of PVST in RES and LMWH groups were significantly decreased (both p Splenectomy II (all p splenectomy in cirrhotic rat. Regulation of platelet function and induction of platelet apoptosis might be the underlying mechanisms. PMID:27433290

  8. Modeling nitrogen plasmas produced by intense electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Angus, J. R.; Swanekamp, S. B.; Schumer, J. W.; Hinshelwood, D. D. [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Mosher, D.; Ottinger, P. F. [Independent contractors for NRL through Engility, Inc., Alexandria, Virginia 22314 (United States)

    2016-05-15

    A new gas–chemistry model is presented to treat the breakdown of a nitrogen gas with pressures on the order of 1 Torr from intense electron beams with current densities on the order of 10 kA/cm{sup 2} and pulse durations on the order of 100 ns. For these parameter regimes, the gas transitions from a weakly ionized molecular state to a strongly ionized atomic state on the time scale of the beam pulse. The model is coupled to a 0D–circuit model using the rigid–beam approximation that can be driven by specifying the time and spatial profiles of the beam pulse. Simulation results are in good agreement with experimental measurements of the line–integrated electron density from experiments done using the Gamble II generator at the Naval Research Laboratory. It is found that the species are mostly in the ground and metastable states during the atomic phase, but that ionization proceeds predominantly through thermal ionization of optically allowed states with excitation energies close to the ionization limit.

  9. Effect of sodium aescinate treatment on PCOS rat model with insulin resistance.

    Science.gov (United States)

    Chen, L; Hu, L M; Wang, Y F; Yang, H Y; Huang, X Y; Zhou, W; Sun, H X

    2017-01-01

    Recent studies indicated that insulin resistance may contribute to the pathogenesis of polycystic ovary syndrome (PCOS); however, the specific mechanism is still unclear. To investigate the effect of sodium aescinate (SA) on PCOS-IR rat models. Sixty rats were randomly divided into the five groups: un-treated rats (n = 12), PCOS-IR group (n = 12), PCOS-IR group plus 50 mg/kg SA (n = 12), PCOS-IR group plus 10 mg/kg SA (n = 12), PCOS-IR group plus 150 mg/kg metformin (n = 12). On day 21, rats were sacrificed, and H(and)E staining was performed for histopathologic examination of the ovaries; moreover, the serum level of follicle-stimulating hormone (FSH), testosterone, and luteotropic hormone (LH) were measured, and the expression as well as phosphorylation of PI3K, Akt and Gsk-3β were examined using western blot assay. High dosage of SA treatment improved the morphological features of the ovaries in PCOS rats, and also induced significant decrease in serum expression of testosterone and LH/FSH ratio and significant decrease in the expression of p-PI3K, p-Akt and p-Gsk-3β. Our results demonstrated that SA treatment could alleviate the symptom of PCOS in rat model through regulating the PI3K/Akt/GSK3-β pathway (Fig. 4, Ref. 22).

  10. A New Experimental Polytrauma Model in Rats: Molecular Characterization of the Early Inflammatory Response

    Directory of Open Access Journals (Sweden)

    Sebastian Weckbach

    2012-01-01

    Full Text Available Background. The molecular mechanisms of the immune response after polytrauma are highly complex and far from fully understood. In this paper, we characterize a new standardized polytrauma model in rats based on the early molecular inflammatory and apoptotic response. Methods. Male Wistar rats (250 g, 6–10/group were anesthetized and exposed to chest trauma (ChT, closed head injury (CHI, or Tib/Fib fracture including a soft tissue trauma (Fx + STT or to the following combination of injuries: (1 ChT; (2 ChT + Fx + STT; (3 ChT + CHI; (4 CHI; (5 polytrauma (PT = ChT + CHI + Fx + STT. Sham-operated rats served as negative controls. The inflammatory response was quantified at 2 hours and 4 hours after trauma by analysis of “key” inflammatory mediators, including selected cytokines and complement components, in serum and bronchoalveolar (BAL fluid samples. Results. Polytraumatized (PT rats showed a significant systemic and intrapulmonary release of cytokines, chemokines, and complement anaphylatoxins, compared to rats with isolated injuries or selected combinations of injuries. Conclusion. This new rat model appears to closely mimic the early immunological response of polytrauma observed in humans and may provide a valid basis for evaluation of the complex pathophysiology and future therapeutic immune modulatory approaches in experimental polytrauma.

  11. A New Experimental Polytrauma Model in Rats: Molecular Characterization of the Early Inflammatory Response

    Science.gov (United States)

    Weckbach, Sebastian; Perl, Mario; Heiland, Tim; Braumüller, Sonja; Stahel, Philip F.; Flierl, Michael A.; Ignatius, Anita; Gebhard, Florian; Huber-Lang, Markus

    2012-01-01

    Background. The molecular mechanisms of the immune response after polytrauma are highly complex and far from fully understood. In this paper, we characterize a new standardized polytrauma model in rats based on the early molecular inflammatory and apoptotic response. Methods. Male Wistar rats (250 g, 6–10/group) were anesthetized and exposed to chest trauma (ChT), closed head injury (CHI), or Tib/Fib fracture including a soft tissue trauma (Fx + STT) or to the following combination of injuries: (1) ChT; (2) ChT + Fx + STT; (3) ChT + CHI; (4) CHI; (5) polytrauma (PT = ChT + CHI + Fx + STT). Sham-operated rats served as negative controls. The inflammatory response was quantified at 2 hours and 4 hours after trauma by analysis of “key” inflammatory mediators, including selected cytokines and complement components, in serum and bronchoalveolar (BAL) fluid samples. Results. Polytraumatized (PT) rats showed a significant systemic and intrapulmonary release of cytokines, chemokines, and complement anaphylatoxins, compared to rats with isolated injuries or selected combinations of injuries. Conclusion. This new rat model appears to closely mimic the early immunological response of polytrauma observed in humans and may provide a valid basis for evaluation of the complex pathophysiology and future therapeutic immune modulatory approaches in experimental polytrauma. PMID:22481866

  12. Radiation-induced cognitive dysfunction: an experimental model in the old rat

    Energy Technology Data Exchange (ETDEWEB)

    Lamproglou, Ioannis; Chen, QI Ming; Boisserie, Gilbert; Mazeron, Jean-Jacques; Poisson, Michel; Baillet, Francois; Le Poncin, Monique; Delattre, Jean-Yves

    1995-01-01

    Purpose: To develop a model of radiation-induced behavioral dysfunction. Methods and Materials: A course of whole brain radiation therapy (30 Gy/10 fractions/12 days) was administered to 26 Wistar rats ages 16-27 months, while 26 control rats received sham irradiation. Sequential behavioral studies including one-way avoidance, two-way avoidance, and a standard operant conditioning method (press-lever avoidance) were undertaken. In addition, rats were studied in a water maze 7 months postradiation therapy. Results: Prior to radiation therapy, both groups were similar. No difference was found 1 and 3 months postradiation therapy. At 6-7 months postradiation therapy, irradiated rats had a much lower percentage of avoidance than controls for one-way avoidance (23% vs. 55%, p {<=} 0.001) and two-way avoidance (18% vs. 40%, p {<=} 0.01). Seven months postradiation therapy the reaction time was increased (press-lever avoidance, 11.20 s vs. 8.43 s, p {<=} 0.05) and the percentage of correct response was lower (water maze, 53% vs. 82%) in irradiated rats compared with controls. Pathological examination did not demonstrate abnormalities of the irradiated brains at the light microscopic level. Conclusion: Behavioral dysfunction affecting mainly memory can be demonstrated following conventional radiation therapy in old rats. This model can be used to study the pathogenesis of radiation-induced cognitive changes.

  13. Radiation-induced cognitive dysfunction: an experimental model in the old rat

    International Nuclear Information System (INIS)

    Lamproglou, Ioannis; Chen, QI Ming; Boisserie, Gilbert; Mazeron, Jean-Jacques; Poisson, Michel; Baillet, Francois; Le Poncin, Monique; Delattre, Jean-Yves

    1995-01-01

    Purpose: To develop a model of radiation-induced behavioral dysfunction. Methods and Materials: A course of whole brain radiation therapy (30 Gy/10 fractions/12 days) was administered to 26 Wistar rats ages 16-27 months, while 26 control rats received sham irradiation. Sequential behavioral studies including one-way avoidance, two-way avoidance, and a standard operant conditioning method (press-lever avoidance) were undertaken. In addition, rats were studied in a water maze 7 months postradiation therapy. Results: Prior to radiation therapy, both groups were similar. No difference was found 1 and 3 months postradiation therapy. At 6-7 months postradiation therapy, irradiated rats had a much lower percentage of avoidance than controls for one-way avoidance (23% vs. 55%, p ≤ 0.001) and two-way avoidance (18% vs. 40%, p ≤ 0.01). Seven months postradiation therapy the reaction time was increased (press-lever avoidance, 11.20 s vs. 8.43 s, p ≤ 0.05) and the percentage of correct response was lower (water maze, 53% vs. 82%) in irradiated rats compared with controls. Pathological examination did not demonstrate abnormalities of the irradiated brains at the light microscopic level. Conclusion: Behavioral dysfunction affecting mainly memory can be demonstrated following conventional radiation therapy in old rats. This model can be used to study the pathogenesis of radiation-induced cognitive changes

  14. Radiation-induced cognitive dysfunction: An experimental model in the old rat

    International Nuclear Information System (INIS)

    Lamproglou, I.; Chen, Q.M.; Poisson, M.

    1995-01-01

    To develop a model of radiation-induced behavioral dysfunction. A course of whole brain radiation therapy (30 Gy/10 fractions/12 days) was administered to 26 Wistar rats ages 16-27 months, while 26 control rats received sham irradiation. Sequential behavioral studies including one-way avoidance, two-way avoidance, and a standard operant conditioning method (press-lever avoidance) were undertaken. In addition, rats were studied in a water maze 7 months postradiation therapy. Prior to radiation therapy, both groups were similar. No difference was found 1 and 3 months postradiation therapy. At 6-7 months postradiation therapy, irradiated rats had a much lower percentage of avoidance than controls for one-way avoidance (23% vs. 55%, p ≤ 0.001) and two-way avoidance (18% vs. 40%, p ≤ 0.01). Seven months postradiation therapy the reaction time was increased (press-lever avoidance, 11.20 s vs. 8.43 s, p ≤ 0.05) and the percentage of correct response was lower (water maze, 53% vs. 82%) in irradiated rats compared with controls. Pathological examination did not demonstrate abnormalities of the irradiated brains at the light microscopic level. Behavioral dysfunction affecting mainly memory can be demonstrated following conventional radiation therapy in old rats. This model can be used to study the pathogenesis of radiation-induced cognitive changes. 15 refs., 3 figs., 1 tab

  15. Generation of muscular dystrophy model rats with a CRISPR/Cas system.

    Science.gov (United States)

    Nakamura, Katsuyuki; Fujii, Wataru; Tsuboi, Masaya; Tanihata, Jun; Teramoto, Naomi; Takeuchi, Shiho; Naito, Kunihiko; Yamanouchi, Keitaro; Nishihara, Masugi

    2014-07-09

    Duchenne muscular dystrophy (DMD) is an X-linked lethal muscle disorder caused by mutations in the Dmd gene encoding Dystrophin. DMD model animals, such as mdx mice and canine X-linked muscular dystrophy dogs, have been widely utilized in the development of a treatment for DMD. Here, we demonstrate the generation of Dmd-mutated rats using a clustered interspaced short palindromic repeats (CRISPR)/Cas system, an RNA-based genome engineering technique that is also adaptive to rats. We simultaneously targeted two exons in the rat Dmd gene, which resulted in the absence of Dystrophin expression in the F0 generation. Dmd-mutated rats exhibited a decline in muscle strength, and the emergence of degenerative/regenerative phenotypes in the skeletal muscle, heart, and diaphragm. These mutations were heritable by the next generation, and F1 male rats exhibited similar phenotypes in their skeletal muscles. These model rats should prove to be useful for developing therapeutic methods to treat DMD.

  16. Step training in a rat model for complex aneurysmal vascular microsurgery

    Directory of Open Access Journals (Sweden)

    Martin Dan

    2015-12-01

    Full Text Available Introduction: Microsurgery training is a key step for the young neurosurgeons. Both in vascular and peripheral nerve pathology, microsurgical techniques are useful tools for the proper treatment. Many training models have been described, including ex vivo (chicken wings and in vivo (rat, rabbit ones. Complex microsurgery training include termino-terminal vessel anastomosis and nerve repair. The aim of this study was to describe a reproducible complex microsurgery training model in rats. Materials and methods: The experimental animals were Brown Norway male rats between 10-16 weeks (average 13 and weighing between 250-400g (average 320g. We performed n=10 rat hind limb replantations. The surgical steps and preoperative management are carefully described. We evaluated the vascular patency by clinical assessment-color, temperature, capillary refill. The rats were daily inspected for any signs of infections. The nerve regeneration was assessed by foot print method. Results: There were no case of vascular compromise or autophagia. All rats had long term survival (>90 days. The nerve regeneration was clinically completed at 6 months postoperative. The mean operative time was 183 minutes, and ischemia time was 25 minutes.

  17. An animal model to study lower urinary tract symptoms and erectile dysfunction: the hyperlipidaemic rat.

    Science.gov (United States)

    Rahman, Nadeem U; Phonsombat, Surat; Bochinski, Derek; Carrion, Rafael E; Nunes, Lora; Lue, Tom F

    2007-09-01

    To present evidence that rats fed a high-fat diet could serve as a useful animal model to study both lower urinary tract symptoms (LUTS) and erectile dysfunction (ED), as recent epidemiological studies have shown a strong association between LUTS and ED but the physiological basis behind this relationship is unknown. In all, 24 male Sprague-Dawley rats were divided into two groups: nine controls were fed a 'normal' diet and 15 were fed a high-fat diet (hyperlipidaemic rats). After 6 months all the rats had bladder and erectile functions evaluated using awake cystometry and cavernosal nerve electrostimulation, respectively. After the functional studies were completed, the penis, prostate and bladder were collected for immunohistochemical analysis. The hyperlipidaemic rats had significantly higher serum cholesterol and low-density lipoprotein than the controls (P enlargement, bladder overactivity, and ED. This rat model could be a useful research tool for understanding the common causes of LUTS and ED, as well as facilitating the development of preventive measures and better therapies to treat both conditions.

  18. One-electron reduction of mitomycin c by rat liver : role of cytochrome P-450 and NADPH-cytochrome P-450 reductase

    NARCIS (Netherlands)

    Vromans, R M; Van de Straat, R; Groeneveld, M.; Vermeulen, N P

    1. The role of cytochrome P-450 in the one-electron reduction of mitomycin c was studied in rat hepatic microsomal systems and in reconstituted systems of purified cytochrome P-450. Formation of H2O2 from redox cycling of the reduced mitomycin c in the presence of O2 and the alkylation of

  19. Intersite electron correlations in a Hubbard model on inhomogeneous lattices

    International Nuclear Information System (INIS)

    Takemori, Nayuta; Koga, Akihisa; Hafermann, Hartmut

    2016-01-01

    We study intersite electron correlations in the half-filled Hubbard model on square lattices with periodic and open boundary conditions by means of a real-space dual fermion approach. By calculating renormalization factors, we clarify that nearest-neighbor intersite correlations already significantly reduce the critical interaction. The Mott transition occurs at U/t ∼ 6.4, where U is the interaction strength and t is the hopping integral. This value is consistent with quantum Monte Carlo results. It shows the importance of short-range intersite correlations, which are taken into account in the framework of the real-space dual fermion approach. (paper)

  20. An experimental electronic model for a neuronal cell

    International Nuclear Information System (INIS)

    Campos-Cantón, I; Martel-Gallegos, G; Rangel-López, A; Vertiz-Hérnandez, A; Zarazúa, S

    2014-01-01

    Over the last two decades, the study of information transmission in living beings has acquired great relevance, because it regulates and conducts the functioning of all of the organs in the body. In information transmission pathways, the neuron plays an important role in that it receives, transmits, and processes electrical signals from different parts of the human body; these signals are transmitted as electrical impulses called action potentials, and they transmit information from one neuron to another. In this work, and with the aim of developing experiments for teaching biological processes, we implemented an electronic circuit of the neuron cell device and its mathematical model based on piecewise linear functions. (paper)

  1. Ocular changes in TgF344-AD rat model of Alzheimer's disease.

    Science.gov (United States)

    Tsai, Yuchun; Lu, Bin; Ljubimov, Alexander V; Girman, Sergey; Ross-Cisneros, Fred N; Sadun, Alfredo A; Svendsen, Clive N; Cohen, Robert M; Wang, Shaomei

    2014-01-29

    Alzheimer's disease (AD) is the most common neurodegenerative disorder characterized by progressive decline in learning, memory, and executive functions. In addition to cognitive and behavioral deficits, vision disturbances have been reported in early stage of AD, well before the diagnosis is clearly established. To further investigate ocular abnormalities, a novel AD transgenic rat model was analyzed. Transgenic (Tg) rats (TgF344-AD) heterozygous for human mutant APPswe/PS1ΔE9 and age-matched wild type (WT) rats, as well as 20 human postmortem retinal samples from both AD and healthy donors were used. Visual function in the rodent was analyzed using the optokinetic response and luminance threshold recording from the superior colliculus. Immunohistochemistry on retinal and brain sections was used to detect various markers including amyloid-β (Aβ) plaques. As expected, Aβ plaques were detected in the hippocampus, cortex, and retina of Tg rats. Plaque-like structures were also found in two AD human whole-mount retinas. The choroidal thickness was significantly reduced in both Tg rat and in AD human eyes when compared with age-matched controls. Tg rat eyes also showed hypertrophic retinal pigment epithelial cells, inflammatory cells, and upregulation of complement factor C3. Although visual acuity was lower in Tg than in WT rats, there was no significant difference in the retinal ganglion cell number and retinal vasculature. In this study, we observed pathological changes in the choroid and in RPE cells in the TgF344-AD rat model; choroidal thinning was observed further in human AD retina. Along with Ab deposition, the inflammatory response was manifested by microglial recruitment and complement activation. Further studies are needed to elucidate the significance and mechanisms of these pathological changes [corrected].

  2. Model Development for MODIS Thermal Band Electronic Crosstalk

    Science.gov (United States)

    Chang, Tiejun; Wu, Aisheng; Geng, Xu; Li, Yonghonh; Brinkman, Jake; Keller, Graziela; Xiong, Xiaoxiong

    2016-01-01

    MODerate-resolution Imaging Spectroradiometer (MODIS) has 36 bands. Among them, 16 thermal emissive bands covering a wavelength range from 3.8 to 14.4 m. After 16 years on-orbit operation, the electronic crosstalk of a few Terra MODIS thermal emissive bands developed substantial issues that cause biases in the EV brightness temperature measurements and surface feature contamination. The crosstalk effects on band 27 with center wavelength at 6.7 m and band 29 at 8.5 m increased significantly in recent years, affecting downstream products such as water vapor and cloud mask. The crosstalk effect is evident in the near-monthly scheduled lunar measurements, from which the crosstalk coefficients can be derived. The development of an alternative approach is very helpful for independent verification.In this work, a physical model was developed to assess the crosstalk impact on calibration as well as in Earth view brightness temperature retrieval. This model was applied to Terra MODIS band 29 empirically to correct the Earth brightness temperature measurements. In the model development, the detectors nonlinear response is considered. The impact of the electronic crosstalk is assessed in two steps. The first step consists of determining the impact on calibration using the on-board blackbody (BB). Due to the detectors nonlinear response and large background signal, both linear and nonlinear coefficients are affected by the crosstalk from sending bands. The second step is to calculate the effects on the Earth view brightness temperature retrieval. The effects include those from affected calibration coefficients and the contamination of Earth view measurements. This model links the measurement bias with crosstalk coefficients, detector non-linearity, and the ratio of Earth measurements between the sending and receiving bands. The correction of the electronic cross talk can be implemented empirically from the processed bias at different brightness temperature. The implementation

  3. Bilateral Cavernous Nerve Crush Injury in the Rat Model: A Comparative Review of Pharmacologic Interventions.

    Science.gov (United States)

    Haney, Nora M; Nguyen, Hoang M T; Honda, Matthew; Abdel-Mageed, Asim B; Hellstrom, Wayne J G

    2018-04-01

    It is common for men to develop erectile dysfunction after radical prostatectomy. The anatomy of the rat allows the cavernous nerve (CN) to be identified, dissected, and injured in a controlled fashion. Therefore, bilateral CN injury (BCNI) in the rat model is routinely used to study post-prostatectomy erectile dysfunction. To compare and contrast the available literature on pharmacologic intervention after BCNI in the rat. A literature search was performed on PubMed for cavernous nerve and injury and erectile dysfunction and rat. Only articles with BCNI and pharmacologic intervention that could be grouped into categories of immune modulation, growth factor therapy, receptor kinase inhibition, phosphodiesterase type 5 inhibition, and anti-inflammatory and antifibrotic interventions were included. To assess outcomes of pharmaceutical intervention on erectile function recovery after BCNI in the rat model. The ratio of maximum intracavernous pressure to mean arterial pressure was the main outcome measure chosen for this analysis. All interventions improved erectile function recovery after BCNI based on the ratio of maximum intracavernous pressure to mean arterial pressure results. Additional end-point analysis examined the corpus cavernosa and/or the major pelvic ganglion and CN. There was extreme heterogeneity within the literature, making accurate comparisons between crush injury and therapeutic interventions difficult. BCNI in the rat is the accepted animal model used to study nerve-sparing post-prostatectomy erectile dysfunction. However, an important limitation is extreme variability. Efforts should be made to decrease this variability and increase the translational utility toward clinical trials in humans. Haney NM, Nguyen HMT, Honda M, et al. Bilateral Cavernous Nerve Crush Injury in the Rat Model: A Comparative Review of Pharmacologic Interventions. Sex Med Rev 2018;6:234-241. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier

  4. [Experimental study on establishment of a simple model of rats crush injury-crush syndrome].

    Science.gov (United States)

    Chen, Xi; Liu, Yuehong; Xu, Wei; Qin, Tingwu; Zhao, Luping; Liu, Shuping; Zhang, Yi; Tan, Hong; Zhou, Yu

    2013-01-01

    To establish a repeatable, simple, and effective model of rat crush injury and crush syndrome. A total of 42 female Sprague Dawley rats (2-month-old, (CS) so as to lay a foundation for further study on CS. weighing 160-180 g) were divided randomly into the control group (n=6) and experimental group (n=36). The rats of the experimental group were used to establish the crush injury and CS model in both lower limbs by self-made crush injury mould. The survival rate and hematuria rate were observed after decompression. The biochemical indexes of blood were measured at 2, 4, 8, 12, 24, and 48 hours after decompression. The samples of muscle, kidney, and heart were harvested for morphological observation. There was no treatment in the control group, and the same tests were performed. Seven rats died and 15 rats had hematuria during compression in the experimental group. Swelling of the lower limb and muscle tissue was observed in the survival rats after reperfusion. The liver function test results showed that the levels of alanine transaminase and aspartate aminotransferase in the experimental group were significantly higher than those in the control group (P congestion and swelling, renal tubular epithelial cell degeneration, edema, necrosis, and myoglobin tube type were found in the kidneys; and myocardial structure had no obvious changes. The method of the crush injury and CS model by self-made crush injury mould is a simple and effective procedure and the experimental result is stable. It is a simple method to establish an effective model of rats crush injury and CS.

  5. Efficacy of Polaprezinc for Acute Radiation Proctitis in a Rat Model

    International Nuclear Information System (INIS)

    Doi, Hiroshi; Kamikonya, Norihiko; Takada, Yasuhiro; Fujiwara, Masayuki; Tsuboi, Keita; Inoue, Hiroyuki; Tanooka, Masao; Nakamura, Takeshi; Shikata, Toshiyuki; Tsujimura, Tohru; Hirota, Shozo

    2011-01-01

    Purpose: The purpose of the present study was to standardize the experimental rat model of radiation proctitis and to examine the efficacy of polaprezinc on radiation proctitis. Methods and Materials: A total of 54 female Wistar rats (5 weeks old) were used. The rats were divided into three groups: those treated with polaprezinc (PZ+), those treated with base alone, exclusive of polaprezinc (PZ-), and those treated without any medication (control). All the rats were irradiated to the rectum. Polaprezinc was prepared as an ointment. The ointment was administered rectally each day after irradiation. All rats were killed on the 10th day after irradiation. The mucosal changes were evaluated endoscopically and pathologically. The results were graded from 0 to 4 and compared according to milder or more severe status, as applicable. Results: According to the endoscopic findings, the proportion of mild changes in the PZ+, PZ-, and control group was 71.4%, 25.0%, and 14.3% respectively. On pathologic examination, the proportion of low-grade findings in the PZ+, PZ-, and control group was 80.0%, 58.3%, and 42.9% for mucosal damage, 85.0%, 41.7%, and 42.9% for a mild degree of inflammation, and 50.0%, 33.3%, and 4.8% for a shallow depth of inflammation, respectively. The PZ+ group tended to have milder mucosal damage than the other groups, according to all criteria used. In addition, significant differences were observed between the PZ+ and control groups regarding the endoscopic findings, degree of inflammation, and depth of inflammation. Conclusions: This model was confirmed to be a useful experimental rat model for radiation proctitis. The results of the present study have demonstrated the efficacy of polaprezinc against acute radiation-induced rectal disorders using the rat model.

  6. Comparison of Allogeneic and Syngeneic Rat Glioma Models by Using MRI and Histopathologic Evaluation.

    Science.gov (United States)

    Biasibetti, Elena; Valazza, Alberto; Capucchio, Maria T; Annovazzi, Laura; Battaglia, Luigi; Chirio, Daniela; Gallarate, Marina; Mellai, Marta; Muntoni, Elisabetta; Peira, Elena; Riganti, Chiara; Schiffer, Davide; Panciani, Pierpaolo; Lanotte, Michele

    2017-03-01

    Research in neurooncology traditionally requires appropriate in vivo animal models, on which therapeutic strategies are tested before human trials are designed and proceed. Several reproducible animal experimental models, in which human physiologic conditions can be mimicked, are available for studying glioblastoma multiforme. In an ideal rat model, the tumor is of glial origin, grows in predictable and reproducible patterns, closely resembles human gliomas histopathologically, and is weakly or nonimmunogenic. In the current study, we used MRI and histopathologic evaluation to compare the most widely used allogeneic rat glioma model, C6-Wistar, with the F98-Fischer syngeneic rat glioma model in terms of percentage tumor growth or regression and growth rate. In vivo MRI demonstrated considerable variation in tumor volume and frequency between the 2 rat models despite the same stereotactic implantation technique. Faster and more reproducible glioma growth occurred in the immunoresponsive environment of the F98-Fischer model, because the immune response is minimized toward syngeneic cells. The marked inability of the C6-Wistar allogeneic system to generate a reproducible model and the episodes of spontaneous tumor regression with this system may have been due to the increased humoral and cellular immune responses after tumor implantation.

  7. Preservation of Retina Ganglion Cell Function by Morphine in a Chronic Ocular-Hypertensive Rat Model

    OpenAIRE

    Husain, Shahid; Abdul, Yasir; Crosson, Craig E.

    2012-01-01

    Morphine, a broad range opioid-receptors agonist, provides retina neuroprotection against glaucomatous injury in chronic experimental rat model. Morphine-induced retina neuroprotection in glaucoma model is mediated partly via inhibition of TNF-alpha production and caspase-3 and caspase-8 activation.

  8. Effects of aspirin and enoxaparin in a rat model of liver fibrosis.

    Science.gov (United States)

    Li, Chen-Jie; Yang, Zhi-Hui; Shi, Xiao-Liu; Liu, De-Liang

    2017-09-21

    To examine the effects of aspirin and enoxaparin on liver function, coagulation index and histopathology in a rat model of liver fibrosis. METHODS Forty-five male Sprague-Dawley rats were randomly divided into the control group (n = 5) and model group (n = 40). Thioacetamide (TAA) was used to induce liver fibrosis in the model group. TAA-induced fibrotic rats received TAA continuously (n = 9), TAA + low-dose aspirin (n = 9), TAA + high-dose aspirin (n = 9) or TAA + enoxaparin (n = 9) for 4 wk. All rats were euthanized after 4 wk, and both hematoxylin-eosin and Masson staining were performed to observe pathological changes in liver tissue. Liver fibrosis was assessed according to the METAVIR score. Compared with untreated cirrhotic controls, a significant improvement in fibrosis grade was observed in the low-dose aspirin, high-dose aspirin and enoxaparin treated groups, especially in the high-dose aspirin treated group. Alanine aminotransferase and total bilirubin were higher, albumin was lower and both prothrombin time and international normalized ratio were prolonged in the four treatment groups compared to controls. No significant differences among the four groups were observed. Aspirin and enoxaparin can alleviate liver fibrosis in this rat model.

  9. Modeling of a new electron-streamer acceleration mechanism

    Science.gov (United States)

    Ihaddadene, K. M. A.; Dwyer, J. R.; Liu, N.; Celestin, S. J.

    2017-12-01

    Lightning stepped leaders and laboratory spark discharges in air are known to produce X-rays [e.g., Dwyer et al., Geophys. Res. lett., 32, L20809, 2005; Kochkin et al., J. Phys. D: Appl. Phys., 45, 425202, 2012]. However, the processes behind the production of these X-rays are still not very well understood. During discharges, encounters between streamers of different polarities are very common. For example, during the formation of a new leader step, the negative streamer zone around the tip of a negative leader and the positive streamers initiated from the posiive part of a bidirectional space leader strongly interact. In laboratory experiments, when streamers are approaching a sharp electrode, streamers with the opposite polarity are initiated from the electrode and collide with the former streamers. Recently, the encounter between negative and positive streamers has been proposed as a plausible mechanism for the production of X-rays by spark discharges [Cooray et la., JASTP, 71, 1890, 2009; Kochkin et al., J. Phys. D: Appl. Phys., 45, 425202, 2012], but modeling results have shown later that the increase of the electric field involved in this process, which is above the conventional breakdown threshold field, is accompanied by a strong increase of the electron density. The resulting increase in the conductivity, in turn, causes this electric field to collapse over a few tens of picoseconds, preventing the electrons reaching high energies and producing significant X-ray emissions [e.g., Ihaddadene and Celestin, Geophys. Res. Lett., 45, 5644, 2015]. In this work, we will present simulation results of a new electron acceleration mechanism for producing runaway electron energies above hundred keV. The mechanism couples multiple single streamers and streamer head-on collisions, similar to a laboratory discharge, and is suitable for explaining the high-energy X-rays produced by discharges in air and by lightning stepped leaders.

  10. Electronic Processes at Organic−Organic Interfaces: Insight from Modeling and Implications for Opto-electronic Devices †

    KAUST Repository

    Beljonne, David

    2011-02-08

    We report on the recent progress achieved in modeling the electronic processes that take place at interfaces between π-conjugated materials in organic opto-electronic devices. First, we provide a critical overview of the current computational techniques used to assess the morphology of organic: organic heterojunctions; we highlight the compromises that are necessary to handle large systems and multiple time scales while preserving the atomistic details required for subsequent computations of the electronic and optical properties. We then review some recent theoretical advances in describing the ground-state electronic structure at heterojunctions between donor and acceptor materials and highlight the role played by charge-transfer and long-range polarization effects. Finally, we discuss the modeling of the excited-state electronic structure at organic:organic interfaces, which is a key aspect in the understanding of the dynamics of photoinduced electron-transfer processes. © 2010 American Chemical Society.

  11. Preliminary Study of Quercetin Affecting the Hypothalamic-Pituitary-Gonadal Axis on Rat Endometriosis Model

    Directory of Open Access Journals (Sweden)

    Yang Cao

    2014-01-01

    Full Text Available In this study, the endometriosis rats model was randomly divided into 6 groups: model control group, ovariectomized group, Gestrinone group, and quercetin high/medium/low dose group. Rats were killed after 3 weeks of administration. The expression levels of serum FSH and LH were detected by ELISA. The localizations and quantities of ERα, ERβ, and PR were detected by immunohistochemistry and western blot. The results showed that the mechanism of quercetin inhibiting the growth of ectopic endometrium on rat endometriosis model may be through the decreasing of serum FSH and LH levels and then reducing local estrogen content to make the ectopic endometrium atrophy. Quercetin can decrease the expression of ERα, ERβ, and PR in hypothalamus, pituitary, and endometrium, thereby inhibiting estrogen and progesterone binding to their receptors to play the role of antiestrogen and progesterone.

  12. Improvement of Radiation-Mediated Immunosuppression of Human NSCLC Tumour Xenografts in a Nude Rat Model

    Directory of Open Access Journals (Sweden)

    Sergey V. Tokalov

    2010-01-01

    Full Text Available Human tumour xenografts in a nude rat model have consistently been used as an essential part of preclinical studies for anticancer drugs activity in human. Commonly, these animals receive whole body irradiation to assure immunosuppression. But whole body dose delivery might be inhomogeneous and the resulting incomplete bone marrow depletion may modify tumour behaviour. To improve irradiation-mediated immunosuppression of human non-small cell lung cancer (NSCLC xenografts in a nude rat model irradiation (2 + 2 Gy from opposite sides of animals has been performed using a conventional X-ray tube. The described modification of whole body irradiation improves growth properties of human NSCLC xenografts in a nude rat model. The design of the whole body irradiation mediated immunosuppression described here for NSCLC xenografts may be useful for research applications involving other types of human tumours.

  13. Removal of thallium by deferasirox in rats as biological model.

    Science.gov (United States)

    Saljooghi, Amir Sh; Fatemi, S Jamiladin

    2011-03-01

    The present research aimed to characterize the potential efficiency of deferasirox in removing thallium after its administration for 30 days following two dose levels of 20 and 160 μm of thallium (III) chloride to male Wistar rats every day. After thallium administration some abnormal clinical signs such as red staining around the eyes, greenish mottling on the liver, weakness, loss of hair and weight, were observed in animals. Deferasirox was given orally to different groups of rats for a period of one week immediately after thallium administration. After chelation therapy, animals were killed by exsanguination from the abdominal aorta, and then thallium and iron concentrations in various tissues were determined by standard addition method. The chelation therapy results showed that deferasirox was able to remove thallium ions from the body and clinical symptoms were also reduced. Copyright © 2010 John Wiley & Sons, Ltd.

  14. Cardioprotection by controlling hyperamylinemia in a "humanized" diabetic rat model.

    Science.gov (United States)

    Despa, Sanda; Sharma, Savita; Harris, Todd R; Dong, Hua; Li, Ning; Chiamvimonvat, Nipavan; Taegtmeyer, Heinrich; Margulies, Kenneth B; Hammock, Bruce D; Despa, Florin

    2014-08-21

    Chronic hypersecretion of the pancreatic hormone amylin is common in humans with obesity or prediabetic insulin resistance and induces amylin aggregation and proteotoxicity in the pancreas. We recently showed that hyperamylinemia also affects the cardiovascular system. Here, we investigated whether amylin aggregates interact directly with cardiac myocytes and whether controlling hyperamylinemia protects the heart. By Western blot, we found abundant amylin aggregates in lysates of cardiac myocytes from obese patients, but not in controls. Aggregated amylin was elevated in failing hearts, suggesting a role in myocyte injury. Using rats overexpressing human amylin in the pancreas (HIP rats) and control myocytes incubated with human amylin, we show that amylin aggregation at the sarcolemma induces oxidative stress and Ca(2+) dysregulation. In time, HIP rats developed cardiac hypertrophy and left-ventricular dilation. We then tested whether metabolites with antiaggregation properties, such as eicosanoid acids, limit myocardial amylin deposition. Rats were treated with an inhibitor of soluble epoxide hydrolase, the enzyme that degrades endogenous eicosanoids. Treatment doubled the blood concentration of eicosanoids, which drastically reduced incorporation of aggregated amylin in cardiac myocytes and blood cells, without affecting pancreatic amylin secretion. Animals in the treated group showed reduced cardiac hypertrophy and left-ventricular dilation. The cardioprotective mechanisms included the mitigation of amylin-induced cardiac oxidative stress and Ca(2+) dysregulation. The results suggest blood amylin as a novel therapeutic target in diabetic heart disease and elevating blood levels of antiaggregation metabolites as a pharmacological strategy to reduce amylin aggregation and amylin-mediated cardiotoxicity. © 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  15. Landauer-Datta-Lundstrom Generalized Transport Model for Nano electronics

    International Nuclear Information System (INIS)

    Kruglyak, Y.

    2014-01-01

    The Landauer-Datta-Lundstrom electron transport model is briefly summarized. If a band structure is given, the number of conduction modes can be evaluated and if a model for a mean-free-path for backscattering can be established, then the near-equilibrium thermoelectric transport coefficients can be calculated using the final expressions listed below for 1D, 2D, and 3D resistors in ballistic, quasi ballistic, and diffusive linear response regimes when there are differences in both voltage and temperature across the device. The final expressions of thermoelectric transport coefficients through the Fermi-Dirac integrals are collected for 1D, 2D, and 3D semiconductors with parabolic band structure and for 2D graphene linear dispersion in ballistic and diffusive regimes with the power law scattering.

  16. Multichannel model of magneto tunneling in disordered electron nanodevices

    International Nuclear Information System (INIS)

    Amado, M.; Dominguez-Adame, F.; Diez, E.

    2005-01-01

    We present a multichannel model of magnetotunneling transport in unintentionally disordered double-barrier GaAs-Al x Ga 1-x As heterostructures. The source of disorder comes from interface roughness at the heterojunctions. Disorder break translational symmetry along the lateral direction and therefore electrons can be scattered off the growth direction. The model correctly describes channel mixing due to these elastic scattering events. The magnetic field applied to the double-barrier heterostructure splits the resonant level into a set of equally-spaced resonances, the level spacing increasing with the magnetic field. We discuss the influence of the various parameters (epilayer widths and magnitude or disorder) on the lineshape of the resonant levels

  17. Modeling electron beam parameters and plasma interface position in an anode plasma electron gun with hydrogen atmosphere

    Science.gov (United States)

    Krauze, A.; Virbulis, J.; Kravtsov, A.

    2018-05-01

    A beam glow discharge based electron gun can be applied as heater for silicon crystal growth systems in which silicon rods are pulled from melt. Impacts of high-energy charged particles cause wear and tear of the gun and generate an additional source of silicon contamination. A steady-state model for electron beam formation has been developed to model the electron gun and optimize its design. Description of the model and first simulation results are presented. It has been shown that the model can simulate dimensions of particle impact areas on the cathode and anode, but further improvements of the model are needed to correctly simulate electron trajectory distribution in the beam and the beam current dependence on the applied gas pressure.

  18. Self-consistent modeling of electron cyclotron resonance ion sources

    International Nuclear Information System (INIS)

    Girard, A.; Hitz, D.; Melin, G.; Serebrennikov, K.; Lecot, C.

    2004-01-01

    In order to predict the performances of electron cyclotron resonance ion source (ECRIS), it is necessary to perfectly model the different parts of these sources: (i) magnetic configuration; (ii) plasma characteristics; (iii) extraction system. The magnetic configuration is easily calculated via commercial codes; different codes also simulate the ion extraction, either in two dimension, or even in three dimension (to take into account the shape of the plasma at the extraction influenced by the hexapole). However the characteristics of the plasma are not always mastered. This article describes the self-consistent modeling of ECRIS: we have developed a code which takes into account the most important construction parameters: the size of the plasma (length, diameter), the mirror ratio and axial magnetic profile, whether a biased probe is installed or not. These input parameters are used to feed a self-consistent code, which calculates the characteristics of the plasma: electron density and energy, charge state distribution, plasma potential. The code is briefly described, and some of its most interesting results are presented. Comparisons are made between the calculations and the results obtained experimentally

  19. Self-consistent modeling of electron cyclotron resonance ion sources

    Science.gov (United States)

    Girard, A.; Hitz, D.; Melin, G.; Serebrennikov, K.; Lécot, C.

    2004-05-01

    In order to predict the performances of electron cyclotron resonance ion source (ECRIS), it is necessary to perfectly model the different parts of these sources: (i) magnetic configuration; (ii) plasma characteristics; (iii) extraction system. The magnetic configuration is easily calculated via commercial codes; different codes also simulate the ion extraction, either in two dimension, or even in three dimension (to take into account the shape of the plasma at the extraction influenced by the hexapole). However the characteristics of the plasma are not always mastered. This article describes the self-consistent modeling of ECRIS: we have developed a code which takes into account the most important construction parameters: the size of the plasma (length, diameter), the mirror ratio and axial magnetic profile, whether a biased probe is installed or not. These input parameters are used to feed a self-consistent code, which calculates the characteristics of the plasma: electron density and energy, charge state distribution, plasma potential. The code is briefly described, and some of its most interesting results are presented. Comparisons are made between the calculations and the results obtained experimentally.

  20. Protective Effect of ECQ on Rat Reflux Esophagitis Model.

    Science.gov (United States)

    Jang, Hyeon-Soon; Han, Jeong Hoon; Jeong, Jun Yeong; Sohn, Uy Dong

    2012-12-01

    This study was designed to determine the protective effect of Rumex Aquaticus Herba extracts containing quercetin-3-β-D-glucuronopyranoside (ECQ) on experimental reflux esophagitis. Reflux esophagitis was induced by surgical procedure. The rats were divided into seven groups, namely normal group, control group, ECQ (1, 3, 10, 30 mg/kg) group and omeprazole (30 mg/kg) group. ECQ and omeprazole groups received intraduodenal administration. The Rats were starved for 24 hours before the experiments, but were freely allowed to drink water. ECQ group attenuated the gross esophagitis significantly compared to that treated with omeprazole in a dose-dependent manner. ECQ decreased the volume of gastric juice and increased the gastric pH, which are similar to those of omeprazole group. In addition, ECQ inhibited the acid output effectively in reflux esophagitis. Significantly increased amounts of malondialdehyde (MDA), myeloperoxidase (MPO) activity and the mucosal depletion of reduced glutathione (GSH) were observed in the reflux esophagitis. ECQ administration attenuated the decrement of the GSH levels and affected the MDA levels and MPO activity. These results suggest that the ECQ has a protective effect which may be attributed to its multiple effects including anti-secretory, anti-oxidative and anti-inflammatory actions on reflux esophagitis in rats.

  1. Radioprotective effect of a metalloporphyrin compound in rat eye model.

    Science.gov (United States)

    Mao, X W; Crapo, J D; Mekonnen, T; Lindsey, N; Martinez, P; Gridley, D S; Slater, J M

    2009-01-01

    The purpose of this study was to evaluate the efficacy of the antioxidant Mn (III) tetrakis (N-ethylpyridinium-2-yl) porphyrin (MnTE-2-PyP) in protecting ocular tissue and retinal microvasculature from radiation damage. 75 rats were treated with Mn TE-2-PyP at 2.5 micro g/injection into one eye an hour before proton irradiation. The radiation was delivered in a single fraction to total doses of 8 Gray (Gy) or 28 Gy; Rats were sacrificed 3 days and 3, 6, 9, and 12 months thereafter for histology and quantification of photoreceptor cell populations and retinal capillary changes. By 6 months following radiation, there was significant loss of retinal outer and inner nuclear layers in eyes receiving radiation only (8 and 28 Gy) (p eyes of rats treated with radiation plus metalloporphyrin. Retinal microvessel length density decreased significantly 6 months following 28 Gy (p eyes showed extensive damage to the photoreceptor layer, whereas the eyes of animals receiving radiation plus MnTE-2-PyP showed almost no morphological damage. MnTE-2-PyP treatment also suppressed radiation-induced apoptosis in our study. These results demonstrated that MnTE-2-PyP protected both photoreceptors and retinal capillaries from radiation damage, suggesting that this metalloporphyrin antioxidant is effective in regulating the damage induced by proton radiation.

  2. Evaluation of deltamethrin kinetics and dosimetry in the maturing rat using a PBPK model

    International Nuclear Information System (INIS)

    Tornero-Velez, Rogelio; Mirfazaelian, Ahmad; Kim, Kyu-Bong; Anand, Sathanandam S.; Kim, Hyo J.; Haines, Wendy T.; Bruckner, James V.; Fisher, Jeffrey W.

    2010-01-01

    Immature rats are more susceptible than adults to the acute neurotoxicity of pyrethroid insecticides like deltamethrin (DLM). A companion kinetics study (Kim et al., in press) revealed that blood and brain levels of the neuroactive parent compound were inversely related to age in rats 10, 21, 40 and 90 days old. The objective of the current study was to modify a physiologically based pharmacokinetic (PBPK) model of DLM disposition in the adult male Sprague-Dawley rat (Mirfazaelian et al., 2006), so blood and target organ dosimetry could be accurately predicted during maturation. Age-specific organ weights and age-dependent changes in the oxidative and hydrolytic clearance of DLM were modeled with a generalized Michaelis-Menten model for growth and the summary equations incorporated into the PBPK model. The model's simulations compared favorably with empirical DLM time-courses in plasma, blood, brain and fat for the four age-groups evaluated (10, 21, 40 and 90 days old). PND 10 pups' area under the 24-h brain concentration time curve (AUC 0-24h ) was 3.8-fold higher than that of the PND 90 adults. Our maturing rat PBPK model allows for updating with age- and chemical-dependent parameters, so pyrethroid dosimetry can be forecast in young and aged individuals. Hence, this model provides a methodology for risk assessors to consider age-specific adjustments to oral Reference Doses on the basis of PK differences.

  3. Modeling Blazar Spectra by Solving an Electron Transport Equation

    Science.gov (United States)

    Lewis, Tiffany; Finke, Justin; Becker, Peter A.

    2018-01-01

    Blazars are luminous active galaxies across the entire electromagnetic spectrum, but the spectral formation mechanisms, especially the particle acceleration, in these sources are not well understood. We develop a new theoretical model for simulating blazar spectra using a self-consistent electron number distribution. Specifically, we solve the particle transport equation considering shock acceleration, adiabatic expansion, stochastic acceleration due to MHD waves, Bohm diffusive particle escape, synchrotron radiation, and Compton radiation, where we implement the full Compton cross-section for seed photons from the accretion disk, the dust torus, and 26 individual broad lines. We used a modified Runge-Kutta method to solve the 2nd order equation, including development of a new mathematical method for normalizing stiff steady-state ordinary differential equations. We show that our self-consistent, transport-based blazar model can qualitatively fit the IR through Fermi g-ray data for 3C 279, with a single-zone, leptonic configuration. We use the solution for the electron distribution to calculate multi-wavelength SED spectra for 3C 279. We calculate the particle and magnetic field energy densities, which suggest that the emitting region is not always in equipartition (a common assumption), but sometimes matter dominated. The stratified broad line region (based on ratios in quasar reverberation mapping, and thus adding no free parameters) improves our estimate of the location of the emitting region, increasing it by ~5x. Our model provides a novel view into the physics at play in blazar jets, especially the relative strength of the shock and stochastic acceleration, where our model is well suited to distinguish between these processes, and we find that the latter tends to dominate.

  4. Applied economic model development algorithm for electronics company

    Directory of Open Access Journals (Sweden)

    Mikhailov I.

    2017-01-01

    Full Text Available The purpose of this paper is to report about received experience in the field of creating the actual methods and algorithms that help to simplify development of applied decision support systems. It reports about an algorithm, which is a result of two years research and have more than one-year practical verification. In a case of testing electronic components, the time of the contract conclusion is crucial point to make the greatest managerial mistake. At this stage, it is difficult to achieve a realistic assessment of time-limit and of wage-fund for future work. The creation of estimating model is possible way to solve this problem. In the article is represented an algorithm for creation of those models. The algorithm is based on example of the analytical model development that serves for amount of work estimation. The paper lists the algorithm’s stages and explains their meanings with participants’ goals. The implementation of the algorithm have made possible twofold acceleration of these models development and fulfilment of management’s requirements. The resulting models have made a significant economic effect. A new set of tasks was identified to be further theoretical study.

  5. A Landau fluid model for dissipative trapped electron modes

    International Nuclear Information System (INIS)

    Hedrick, C.L.; Leboeuf, J.N.; Sidikman, K.L.

    1995-09-01

    A Landau fluid model for dissipative trapped electron modes is developed which focuses on an improved description of the ion dynamics. The model is simple enough to allow nonlinear calculations with many harmonics for the times necessary to reach saturation. The model is motivated by a discussion that starts with the gyro-kinetic equation and emphasizes the importance of simultaneously including particular features of magnetic drift resonance, shear, and Landau effects. To ensure that these features are simultaneously incorporated in a Landau fluid model with only two evolution equations, a new approach to determining the closure coefficients is employed. The effect of this technique is to reduce the matching of fluid and kinetic responses to a single variable, rather than two, and to allow focusing on essential features of the fluctuations in question, rather than features that are only important for other types of fluctuations. Radially resolved nonlinear calculations of this model, advanced in time to reach saturation, are presented to partially illustrate its intended use. These calculations have a large number of poloidal and toroidal harmonics to represent the nonlinear dynamics in a converged steady state which includes cascading of energy to both short and long wavelengths

  6. Hormone-induced rat model of polycystic ovary syndrome: A systematic review.

    Science.gov (United States)

    Noroozzadeh, Mahsa; Behboudi-Gandevani, Samira; Zadeh-Vakili, Azita; Ramezani Tehrani, Fahimeh

    2017-12-15

    Despite polycystic ovary syndrome (PCOS) being one of the most common endocrine disorders affecting reproductive-aged women, the etiopathogenesis and mechanisms of this syndrome remain unclear. Considering the ethical limitations in human studies, animal models that reflect many features of PCOS are crucial resources to investigate this syndrome. We aimed to introduce the most suitable rat model of PCOS that closely mimics the endocrine, ovarian and metabolic disturbances of human PCOS phenotype, while maintaining normal reproductive system morphology in adulthood, in order to further more detailed investigations about PCOS. We searched Pubmed, Science direct, and Web of science between 1990 and 2016, for relevant English manuscripts, using keywords including the "Polycystic Ovary Syndrome AND Rat Model" to generate a subset of citations relevant to our research. Included were those articles that compared at least both ovarian histology or estrous cycle and reproductive hormonal profiles in hormone-induced rat model of PCOS and controls. Differences in the findings between hormone-induced PCOS rats appear to be a result of the degree of transplacental transfer of the steroid administered into the fetus, dose and type of hormone, route of administration and timing and duration of exposure. We conclude that prenatal hormone-induced rat model with a lower dose and shorter time of exposure during the critical period of fetal development that exhibits endocrine, ovarian and metabolic disturbances similar to PCOS in women, while maintaining normal reproductive system morphology in adulthood is more suitable than postnatal hormone-induced rat model to facilitate studies regarding PCOS. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Determination of equilibrium electron temperature and times using an electron swarm model with BOLSIG+ calculated collision frequencies and rate coefficients

    International Nuclear Information System (INIS)

    Pusateri, Elise N.; Morris, Heidi E.; Nelson, Eric M.; Ji, Wei

    2015-01-01

    Electromagnetic pulse (EMP) events produce low-energy conduction electrons from Compton electron or photoelectron ionizations with air. It is important to understand how conduction electrons interact with air in order to accurately predict EMP evolution and propagation. An electron swarm model can be used to monitor the time evolution of conduction electrons in an environment characterized by electric field and pressure. Here a swarm model is developed that is based on the coupled ordinary differential equations (ODEs) described by Higgins et al. (1973), hereinafter HLO. The ODEs characterize the swarm electric field, electron temperature, electron number density, and drift velocity. Important swarm parameters, the momentum transfer collision frequency, energy transfer collision frequency, and ionization rate, are calculated and compared to the previously reported fitted functions given in HLO. These swarm parameters are found using BOLSIG+, a two term Boltzmann solver developed by Hagelaar and Pitchford (2005), which utilizes updated cross sections from the LXcat website created by Pancheshnyi et al. (2012). We validate the swarm model by comparing to experimental effective ionization coefficient data in Dutton (1975) and drift velocity data in Ruiz-Vargas et al. (2010). In addition, we report on electron equilibrium temperatures and times for a uniform electric field of 1 StatV/cm for atmospheric heights from 0 to 40 km. We show that the equilibrium temperature and time are sensitive to the modifications in the collision frequencies and ionization rate based on the updated electron interaction cross sections

  8. Modelling of electronic and vibrational properties of carbon nanostructures

    Science.gov (United States)

    Margine, Elena Roxana

    The main goals of this dissertation work are the analysis and prediction of the properties of nanoscale carbon materials which hold great potential for nanotechnological applications such as strong conductive composites, field-effect transistors, diodes, rechargeable batteries, etc. Some of these exciting applications are already being actively developed, however their design via trial-and-error experimentation is often difficult and expensive. State-of-the-art simulation methods can be used as a powerful tool to streamline the path to practical implementations. In this thesis I use ab initio quantum-mechanical calculations to explore the response of nanoscale carbon materials to doping. A brief overview of the theoretical methods and of some basic concepts on carbon nanotubes are given in the first two chapters. In Chapter 3 we study the effect of doping in double-walled carbon nanotubes. These systems can be considered as nanoscale capacitors since they have two conducting (or semi-conducting) shells. The experimental work of our collaborators demonstrated for the first time that such a capacitor can be realized by the adsorption of bromine anions at the surface of the outer tube. Our theoretical analysis of the experimental results revealed that this quantum system, surprisingly, behaves exactly as the classical Faraday cage: the electric charge always resides on the outside surface of the conductor, even when the pristine tubes are not metallic. In Chapter 4 I present our findings on the phonon frequencies' response to electron doping in single-walled carbon nanotubes. It is well established that when graphite is doped with electrons, carbon-carbon bonds lengthen and all vibrational frequencies soften. However, in semiconducting carbon nanotubes, the frequency of one mode increases at low levels of alkali doping. Having carefully modelled the process with ab initio methods we conclude that the unusual behavior of the vibrational mode depends on which electronic

  9. [Effects of telmisartan on resistin expression in a rat model of nonalcoholic steatohepatitis and insulin resistance].

    Science.gov (United States)

    Zhang, Qiuzan; Wang, Yanrong; Liu, Yingli; Yang, Qian; Wang, Xiuru; Wang, Qiang; Zhang, Chenming; Wang, Bangmao

    2015-04-01

    To investigate the effects of telmisartan on expression of resistin in serum and liver under conditions of nonalcoholic steatohepatitis (NASH) and insulin resistance using a rat model system. Forty-five male Sprague-Dawley rats were randomly divided into a normal control group (NC, n=10), a model control group (MC, n=15), a polyene phosphatidylcholine prevention group (PP, n=10), and a telmisartan prevention group (TP, n=10). The NC group was given a standard diet and the other groups were given a high-fat diet for 16 weeks in order to induce NASH. At the end of week 12, 5 rats in the MC group were sacrificed for pathology confirmation of the NASH model. At the end of week 12, the TP group was given telmisartan (8.0 mg/kg/d) and the PP group was given polyene phosphatidylcholine (8.4 mg/kg/d) for an additional 4 weeks by intragastric administration. At the end of week 16, all rats were sacrificed and body weights recorded. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglycerides (TG), resistin, insulin and fasting blood glucose were measured. The insulin resistance value, HOMA-IR, was assessed by homeostasis mode assessment. Liver expression of the resistin protein was detected by western blotting and of the resistin mRNA was detected by RT-PCR. The F test and LSD test were used for statistical analyses. Compared to the NC group, the body weight and HOMA-IR of rats in the MC group were significantly increased (Pinsulin resistance were significantly lower in the TP group than in the MC group of rats (all Pinsulin resistance in NASH rats by decreasing the expression of serum resistin, and liver resistin protein and mRNA.

  10. Potential neuroprotective effects of acupuncture stimulation on diabetes mellitus in a global ischemic rat model

    International Nuclear Information System (INIS)

    Choi, Samjin; Lee, Gi-Ja; Chae, Su-Jin; Kang, Sung Wook; Park, Hun-Kuk; Yin, Chang-Shik; Lee, Seung-Hoon; Choi, Seok Keun

    2010-01-01

    Acupuncture (ACU) is known to be effective in ischemia treatment, and glutamate (GLU) excitotoxicity is an important factor in neuronal cell death. We observed the effect of ACU on cerebral blood flow (%CBF) and ΔGLU (the changes in GLU release) in the ischemic stroke rat model of diabetic mellitus (DM). A global ischemia was induced using the eleven-vessel occlusion (11-VO) method in 14 Sprague-Dawley rats (DM), which were randomly divided into two groups: the control group and the ACU-treatment group. Extracellular ΔGLU was assessed using an intra-cerebral biosensor system measuring 256 samples per second, simultaneously with %CBF and electroencephalogram. ACU stimulation was applied to ACU points GB34 and GB39 during the ischemic period. Twenty-three diagnostic parameters were proposed first for a detailed analysis of changes in %CBF and GLU release during ischemia/reperfusion. ACU rats showed a significant decrease in ischemic (p < 0.05) and reperfusion %CBF (p < 0.0001) than control rats, and a significantly larger decrease in ischemic ΔGLU (p < 0.05) and peak level of reperfusion ΔGLU (p < 0.005) than control rats. From these results, we suggest that ACU stimulation is responsible for the potential protection of neurons through suppression of %CBF response in the increased plasma osmolality and extracellular ΔGLU in diabetic rats under ischemic conditions

  11. Hepatoprotective Effects of Swimming Exercise against D-Galactose-Induced Senescence Rat Model

    Directory of Open Access Journals (Sweden)

    Chi-Chang Huang

    2013-01-01

    Full Text Available This study investigates whether a 12-week swimming exercise training can prevent liver damage or senescence associated biomarkers in an experimental aging model in rats. Twenty-three male Sprague-Dawley rats were divided into four groups: vehicle treatment with sedentary control (C, , aging induction with sedentary (A, , vehicle treatment with swimming exercise (SW, , and aging induction with swimming exercise (A + SW, . Rats in groups A and AS received intraperitoneal D-galactose injections (150 mg/kg/day for 12 weeks to induce aging. Rats in groups SW and A + SW were subjected to swimming exercise training for 12 weeks. Body weight, liver weight, epididymal fat mass, blood biochemistry, and liver pathology were performed at the end of the experiment. Hepatic senescence protein markers such as β-galactosidase, p53, and p21, as well as the inflammatory mediator, IL-6, were examined. The D-galactose-treated rats exhibited increases in AST and γ-GT plasma levels and β-galactosidase protein expression compared to the control group. Swimming exercise significantly reduced BW, epididymal fat mass, γ-GT activity, and p53, p21, and IL-6 protein levels compared to the aging group. These results suggest that a 12-week swimming exercise program suppresses senescence markers and downregulates inflammatory mediator in the liver tissues of D-galactose-induced aging rats.

  12. Strong interactions between learned helplessness and risky decision-making in a rat gambling model.

    Science.gov (United States)

    Nobrega, José N; Hedayatmofidi, Parisa S; Lobo, Daniela S

    2016-11-18

    Risky decision-making is characteristic of depression and of addictive disorders, including pathological gambling. However it is not clear whether a propensity to risky choices predisposes to depressive symptoms or whether the converse is the case. Here we tested the hypothesis that rats showing risky decision-making in a rat gambling task (rGT) would be more prone to depressive-like behaviour in the learned helplessness (LH) model. Results showed that baseline rGT choice behaviour did not predict escape deficits in the LH protocol. In contrast, exposure to the LH protocol resulted in a significant increase in risky rGT choices on retest. Unexpectedly, control rats subjected only to escapable stress in the LH protocol showed a subsequent decrease in riskier rGT choices. Further analyses indicated that the LH protocol affected primarily rats with high baseline levels of risky choices and that among these it had opposite effects in rats exposed to LH-inducing stress compared to rats exposed only to the escape trials. Together these findings suggest that while baseline risky decision making may not predict LH behaviour it interacts strongly with LH conditions in modulating subsequent decision-making behaviour. The suggested possibility that stress controllability may be a key factor should be further investigated.

  13. Motor Function and Dopamine Release Measurements in Transgenic Huntington’s Disease Model Rats

    Science.gov (United States)

    Ortiz, Andrea N.; Osterhaus, Gregory L.; Lauderdale, Kelli; Mahoney, Luke; Fowler, Stephen C.; von Hörsten, Stephan; Riess, Olaf; Johnson, Michael A.

    2013-01-01

    Huntington’s disease (HD) is a fatal, genetic, neurodegenerative disorder characterized by deficits in motor and cognitive function. Here, we have quantitatively characterized motor deficiencies and dopamine release dynamics in transgenic HD model rats. Behavioral analyses were conducted using a newly-developed force-sensing runway and a previously-developed force-plate actometer. Gait disturbances were readily observed in transgenic HD rats at 12 to 15 months of age. Additionally, dopamine system challenge by ip injection of amphetamine also revealed that these rats were resistant to the expression of focused stereotypy compared to wild-type controls. Moreover, dopamine release, evoked by the application of single and multiple electrical stimulus pulses applied at different frequencies, and measured using fast-scan cyclic voltammetry at carbon-fiber microelectrodes, was diminished in transgenic HD rats compared to age-matched wild-type control rats. Collectively, these results underscore the potential contribution of dopamine release alterations to the expression of motor impairments in transgenic HD rats. PMID:22418060

  14. A truncated conical beam model for analysis of the vibration of rat whiskers.

    Science.gov (United States)

    Yan, Wenyi; Kan, Qianhua; Kergrene, Kenan; Kang, Guozheng; Feng, Xi-Qiao; Rajan, Ramesh

    2013-08-09

    A truncated conical beam model is developed to study the vibration behaviour of a rat whisker. Translational and rotational springs are introduced to better represent the constraint conditions at the base of the whiskers in a living rat. Dimensional analysis shows that the natural frequency of a truncated conical beam with generic spring constraints at its ends is inversely proportional to the square root of the mass density. Under all the combinations of the classical free, pinned, sliding or fixed boundary conditions of a truncated conical beam, it is proved that the natural frequency can be expressed as f = α(rb/L(2))E/ρ and the frequency coefficient α only depends on the ratio of the radii at the two ends of the beam. The natural frequencies of a representative rat whisker are predicted for two typical situations: freely whisking in air and the tip touching an object. Our numerical results show that there exists a window where the natural frequencies of a rat whisker are very sensitive to the change of the rotational constraint at the base. This finding is also confirmed by the numerical results of 18 whiskers with their data available from literature. It can be concluded that the natural frequencies of a rat whisker can be adjusted within a wide range through manipulating the constraints of the follicle on the rat base by a behaving animal. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Vagus nerve stimulation delivered during motor rehabilitation improves recovery in a rat model of stroke.

    Science.gov (United States)

    Khodaparast, Navid; Hays, Seth A; Sloan, Andrew M; Fayyaz, Tabbassum; Hulsey, Daniel R; Rennaker, Robert L; Kilgard, Michael P

    2014-09-01

    Neural plasticity is widely believed to support functional recovery following brain damage. Vagus nerve stimulation paired with different forelimb movements causes long-lasting map plasticity in rat primary motor cortex that is specific to the paired movement. We tested the hypothesis that repeatedly pairing vagus nerve stimulation with upper forelimb movements would improve recovery of motor function in a rat model of stroke. Rats were separated into 3 groups: vagus nerve stimulation during rehabilitation (rehab), vagus nerve stimulation after rehab, and rehab alone. Animals underwent 4 training stages: shaping (motor skill learning), prelesion training, postlesion training, and therapeutic training. Rats were given a unilateral ischemic lesion within motor cortex and implanted with a left vagus nerve cuff. Animals were allowed 1 week of recovery before postlesion baseline training. During the therapeutic training stage, rats received vagus nerve stimulation paired with each successful trial. All 17 trained rats demonstrated significant contralateral forelimb impairment when performing a bradykinesia assessment task. Forelimb function was recovered completely to prelesion levels when vagus nerve stimulation was delivered during rehab training. Alternatively, intensive rehab training alone (without stimulation) failed to restore function to prelesion levels. Delivering the same amount of stimulation after rehab training did not yield improvements compared with rehab alone. These results demonstrate that vagus nerve stimulation repeatedly paired with successful forelimb movements can improve recovery after motor cortex ischemia and may be a viable option for stroke rehabilitation. © The Author(s) 2014.

  16. Thrombolytic effects in vivo of nattokinase in a carrageenan-induced rat model of thrombosis.

    Science.gov (United States)

    Xu, Jianping; Du, Ming; Yang, Xiulin; Chen, Qingquan; Chen, Hong; Lin, Dong-Hong

    2014-01-01

    Nattokinase is a serine protease produced by Bacillus subtilis during the fermentation of the soybean product natto. The fibrinolytic activity and thrombolytic effects of nattokinase have been observed in vitro, but the effect in vivo has still to be researched. The objective of this study was to demonstrate the activity of nattokinase in vivo. To establish a rat model of thrombosis, κ-carrageenan was injected subcutaneously into the toes of Sprague-Dawley (SD) rats. Histological examination confirmed thrombosis. The rats were then treated with varying doses of nattokinase and the resulting thrombolysis was histologically assessed. ELISA was used to determine the levels of the fibrin/fibrinogen degradation products (FDPs) and D-dimer, which are sensitive indices of fibrinolytic activity. Vermis kinase, a known thrombolytic agent, was used as a positive control. Biopsy results revealed partial thrombolysis in the tail vessels of the rats treated with nattokinase or vermis kinase. FDP and D-dimer levels were higher in rats treated with high-dose nattokinase than in those treated with saline. No difference in FDP or D-dimer levels was observed between rats treated with high-dose nattokinase and those treated with vermis kinase. Both the histological and physiological evidence from this study indicate that nattokinase exerts thrombolytic effects in vivo.

  17. Novel Rat Model of Repetitive Portal Venous Embolization Mimicking Human Non-Cirrhotic Idiopathic Portal Hypertension.

    Science.gov (United States)

    Klein, Sabine; Hinüber, Christian; Hittatiya, Kanishka; Schierwagen, Robert; Uschner, Frank Erhard; Strassburg, Christian P; Fischer, Hans-Peter; Spengler, Ulrich; Trebicka, Jonel

    2016-01-01

    Non-cirrhotic idiopathic portal hypertension (NCIPH) is characterized by splenomegaly, anemia and portal hypertension, while liver function is preserved. However, no animal models have been established yet. This study assessed a rat model of NCIPH and characterized the hemodynamics, and compared it to human NCIPH. Portal pressure (PP) was measured invasively and coloured microspheres were injected in the ileocecal vein in rats. This procedure was performed weekly for 3 weeks (weekly embolization). Rats without and with single embolization served as controls. After four weeks (one week after last embolization), hemodynamics were investigated, hepatic fibrosis and accumulation of myofibroblasts were analysed. General characteristics, laboratory analyses and liver histology were collected in patients with NCIPH. Weekly embolization induced a hyperdynamic circulation, with increased PP. The mesenteric flow and hepatic hydroxyproline content was significantly higher in weekly embolized compared to single embolized rats (mesenteric flow +54.1%, hydroxyproline +41.7%). Mesenteric blood flow and shunt volumes increased, whereas splanchnic vascular resistance was decreased in the weekly embolization group. Fibrotic markers αSMA and Desmin were upregulated in weekly embolized rats. This study establishes a model using repetitive embolization via portal veins, comparable with human NCIPH and may serve to test new therapies.

  18. Influence of manual therapy on functional mobility after joint injury in a rat model.

    Science.gov (United States)

    Ruhlen, Rachel L; Snider, Eric J; Sargentini, Neil J; Worthington, Bart D; Singh, Vineet K; Pazdernik, Vanessa K; Johnson, Jane C; Degenhardt, Brian F

    2013-10-01

    Animal models can be used to investigate manual therapy mechanisms, but testing manipulation in animal models is problematic because animals cannot directly report their pain. To develop a rat model of inflammatory joint injury to test the efficacy of manual therapy in reducing nociception and restoring function. The authors induced acute inflammatory joint injury in rats by injecting carrageenan into the ankle and then measured voluntary running wheel activity in treated and untreated rats. Treatments included manual therapy applied to the ankle and knee of the injured limb and several analgesic medications (eg, morphine, ketorolac, prednisone). Intra-articular injection of carrageenan to the ankle produced significant swelling (diameter of the ankle increased by 64% after injection; P=.004) and a robust reduction in voluntary running wheel activity (running distance reduced by 91% compared with controls; Pmanual therapy nor analgesic medications increased running wheel activity relative to untreated rats. Voluntary running wheel activity appears to be an appropriate functional measure to evaluate the impact of an acute inflammatory joint injury. However, efforts to treat the injury did not restore running relative to untreated rats.

  19. Theoretical modeling of electronic transport in molecular devices

    Science.gov (United States)

    Piccinin, Simone

    In this thesis a novel approach for simulating electronic transport in nanoscale structures is introduced. We consider an open quantum system (the electrons of structure) accelerated by an external electromotive force and dissipating energy through inelastic scattering with a heat bath (phonons) acting on the electrons. This method can be regarded as a quantum-mechanical extension of the semi-classical Boltzmann transport equation. We use periodic boundary conditions and employ Density Functional Theory to recast the many-particle problem in an effective single-particle mean-field problem. By explicitly treating the dissipation in the electrodes, the behavior of the potential is an outcome of our method, at variance with the scattering approaches based on the Landauer formalism. We study the self-consistent steady-state solution, analyzing the out-of-equilibrium electron distribution, the electrical characteristics, the behavior of the self-consistent potential and the density of states of the system. We apply the method to the study of electronic transport in several molecular devices, consisting of small organic molecules or atomic wires sandwiched between gold surfaces. For gold wires we recover the experimental evidence that transport in short wires is ballistic, independent of the length of the wire and with conductance of one quantum. In benzene-1,4-dithiol we find that the delocalization of the frontier orbitals of the molecule is responsible for the high value of conductance and that, by inserting methylene groups to decouple the sulfur atoms from the carbon ring, the current is reduced, in agreement with the experimental measurements. We study the effect a geometrical distortion in a molecular device, namely the relative rotation of the carbon rings in a biphenyl-4,4'-dithiol molecule. We find that the reduced coupling between pi orbitals of the rings induced by the rotation leads to a reduction of the conductance and that this behavior is captured by a

  20. General developmental health in the VPA-rat model of autism

    DEFF Research Database (Denmark)

    Favre, Mônica R; Rinaldi Barkat, Tania; Lamendola, Deborah

    2013-01-01

    Autism is a neurodevelopmental condition diagnosed by impaired social interaction, abnormal communication and, stereotyped behaviors. While post-mortem and imaging studies have provided good insights into the neurobiological symptomology of autism, animal models can be used to study...... with VPA during early pregnancy show an increased risk for giving birth to an autistic child. In rats, early embryonic exposure, around the time of neural tube closure, leads to autism-like anatomical and behavioral abnormalities in the offspring. Considering the increasing use of the VPA rat model, we...

  1. Liraglutide Improves Hypertension and Metabolic Perturbation in a Rat Model of Polycystic Ovarian Syndrome

    Science.gov (United States)

    Hoang, Vanessa; Bi, Jiangjiang; Mohankumar, Sheba M.; Vyas, Arpita K.

    2015-01-01

    Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder in women of reproductive age, with a prevalence of 5–8%. Type 2 diabetes and cardiovascular disease (CVD) are its long-term complications. Targeted therapies addressing both these complications together are lacking. Glucagon like peptide-1 (GLP-1) agonists that are used to treat type 2 diabetes mellitus have beneficial effects on the cardiovascular system. Hence we hypothesized that a GLP-1 agonist would improve both cardiovascular and metabolic outcomes in PCOS. To test this hypothesis, we used an established rat model of PCOS. Prepubertal female Sprague Dawley rats were sham-implanted or implanted s.c. with dihydrotestosterone (DHT) pellets (90 day release; 83μg/day). At 12 wks of age, sham implanted rats received saline injections and the DHT treated animals were administered either saline or liraglutide (0.2mg/kg s.c twice daily) for 4 weeks. Subgroups of rats were implanted with telemeters between 12-13 weeks of age to monitor blood pressure. DHT implanted rats had irregular estrus cycles and were significantly heavier than the control females at 12 weeks (mean± SEM 251.9±3.4 vs 216.8±3.4 respectively; pDHT treated rats significantly decreased body weight (mean± SEM 294.75 ±3.2 in DHT+ saline vs 276.25±2.7 in DHT+ liraglutide group respectively; pDHT implanted rats significantly improved glucose excursion during oral glucose tolerance test (area under the curve: DHT+ saline 28674±310 vs 24990± 420 in DHT +liraglutide p DHT rats were hypertensive and liraglutide treatment significantly improved mean arterial pressure. These results suggest that GLP-1 treatment could improve DHT–induced metabolic and blood pressure deficits associated with PCOS. PMID:26010091

  2. Gallic Acid Attenuates Postoperative Intra-Abdominal Adhesion by Inhibiting Inflammatory Reaction in a Rat Model

    Science.gov (United States)

    Wei, Guangbing; Wu, Yunhua; Gao, Qi; Shen, Cong; Chen, Zilu; Wang, Kang; Yu, Junhui

    2018-01-01

    Background Intra-abdominal adhesion is one of the most common complications after abdominal surgery. The efficacy of current treatments for intra-abdominal adhesion is unsatisfactory. In this study, we investigated the effect of gallic acid on the prevention and treatment of intra-abdominal adhesions after abdominal surgery using an intra-abdominal adhesion rat model. Material/Methods The experimental rats were randomly divided into the sham operation group, the control group, the chitosan group, and 3 gallic acid groups of different concentrations. All rats except those in the sham operation group received cecal abrasion to induce adhesion. From the first postoperative day, the rats in the gallic acid groups were administered different concentrations of gallic acid in a 2-ml gavage daily. All rats were sacrificed on postoperative day 7, and the degree of intra-abdominal adhesion was evaluated by the naked eye. The amount of collagen deposited between the injured peritoneal tissues was assessed by Sirius red staining. Serum levels of interleukin-6 (IL-6), tumor necrosis factor (TNF-α), and transforming growth factor-β (TGF-β) were measured by ELISA. Western blot was used to detect the level of NF-κB phosphorylation in the injured peritoneal or adhesion tissues of the rats. Results Compared with the control group, the scores of intra-abdominal adhesions in the rats treated with larger doses of gallic acid were significantly decreased, and the degree of inflammation and fibrosis was also significantly decreased. Gallic acid significantly reduced IL-6, TNF-α, and TGF-β1 serum levels. NF-κB phosphorylation in the higher gallic acid groups was significantly reduced. Conclusions Gallic acid inhibits the formation of postoperative intra-abdominal adhesions in rats by inhibiting the inflammatory reaction and fibrogenesis. Gallic acid is a promising drug for preventing intra-abdominal adhesions. PMID:29429982

  3. Effect of TheraCyte-encapsulated parathyroid cells on lumbar fusion in a rat model.

    Science.gov (United States)

    Chen, Sung-Hsiung; Huang, Shun-Chen; Lui, Chun-Chung; Lin, Tzu-Ping; Chou, Fong-Fu; Ko, Jih-Yang

    2012-09-01

    Implantation of TheraCyte 4 × 10(6) live parathyroid cells can increase the bone marrow density of the spine of ovariectomized rats. There has been no published study examining the effect of such implantation on spinal fusion outcomes. The purpose of this study was to examine the effect of TheraCyte-encapsulated parathyroid cells on posterolateral lumbar fusions in a rat model. Forty Sprague-Dawley rats underwent single-level, intertransverse process spinal fusions using iliac crest autograft. The rats were randomly assigned to two groups: Group 1 rats received sham operations on their necks (control; N = 20); Group 2 rats were implanted with TheraCyte-encapsulated 4 × 10(6) live parathyroid cells into the subcutis of their necks (TheraCyte; N = 20). Six weeks after surgery the rats were killed. Fusion was assessed by inspection, manual palpation, radiography, and histology. Blood was drawn to measure the serum levels of calcium, phosphorus, and intact parathyroid hormone (iPTH). Based on manual palpation, the control group had a fusion rate of 33 % (6/18) and the TheraCyte group had a fusion rate of 72 % (13/18) (P = 0.044). Histology confirmed the manual palpation results. Serum iPTH levels were significantly higher in the TheraCyte group compared with the control group (P TheraCyte-encapsulated 4 × 10(6) live parathyroid cells than in control rats without significant change in serum calcium or phosphorus concentrations. As with any animal study, the results may not extrapolate to a higher species. Further studies are needed to determine if these effects are clinically significant.

  4. Analgesic effect of Minocycline in rat model of inflammation-induced visceral pain

    Science.gov (United States)

    Kannampalli, Pradeep; Pochiraju, Soumya; Bruckert, Mitchell; Shaker, Reza; Banerjee, Banani; Sengupta, Jyoti N.

    2014-01-01

    The present study investigates the analgesic effect of minocycline, a semi-synthetic tetracycline antibiotic, in a rat model of inflammation-induced visceral pain. Inflammation was induced in male rats by intracolonic administration of tri-nitrobenzenesulphonic acid (TNBS). Visceral hyperalgesia was assessed by comparing the viscero-motor response (VMR) to graded colorectal distension (CRD) prior and post 7 days after TNBS treatment. Electrophysiology recordings from CRD-sensitive pelvic nerve afferents (PNA) and lumbo-sacral (LS) spinal neurons were performed in naïve and inflamed rats. Colonic inflammation produced visceral hyperalgesia characterized by increase in the VMRs to CRD accompanied with simultaneous activation of microglia in the spinal cord and satellite glial cells (SGCs) in the dorsal root ganglions (DRGs). Selectively inhibiting the glial activation following inflammation by araC (Arabinofuranosyl Cytidine) prevented the development of visceral hyperalgesia. Intrathecal minocycline significantly attenuated the VMR to CRD in inflamed rats, whereas systemic minocycline produced a delayed effect. In electrophysiology experiments, minocycline significantly attenuated the mechanotransduction of CRD-sensitive PNAs and the responses of CRD-sensitive LS spinal neurons in TNBS-treated rats. While the spinal effect of minocycline was observed within 5 min of administration, systemic injection of the drug produced a delayed effect (60 min) in inflamed rats. Interestingly, minocycline did not exhibit analgesic effect in naïve, non-inflamed rats. The results demonstrate that intrathecal injection of minocycline can effectively attenuate inflammation-induced visceral hyperalgesia. Minocycline might as well act on neuronal targets in the spinal cord of inflamed rats, in addition to the widely reported glial inhibitory action to produce analgesia. PMID:24485889

  5. Assessment of mitochondrial electron transport chain function in a primary astrocyte cell model of hyperhomocystinaemia.

    Science.gov (United States)

    Turkes, Fiona; Murphy, Elaine; Land, John; Demiray, Berna; Duberley, Kate; Briddon, Antony; Hargreaves, Iain

    2013-07-01

    Elevated plasma homocysteine (Hcy) has been detected in patients with various neurodegenerative conditions. Studies on neurones and cerebral tissue have revealed that hyperhomocystinaemia may inhibit mitochondrial electron transport chain (ETC) enzyme activity resulting in neuronal morbidity. As astrocytes convey a protective and supportive role towards neurones, we postulated that Hcy-induced astrocytic ETC inhibition may contribute to neurological dysfunction. In order to investigate this hypothesis, we established a cellular model of hyperhomocystinaemia using primary rat astrocytes. Which were incubated were incubated with 200 µM, 500 µM Hcy and the Hcy metabolite, thiolactone (10 µM). Following 96 h of incubation with 200 µM and 500 µM Hcy, an approximate two-fold (1.11 nmol/mg) and three-fold (1.45 nmol/mg) increase in mitochondrial levels of Hcy, respectively, were detected compared to control levels (0.54 nmol/mg). However, on exposure to Hcy (200 or 500 µM) and Hcy-thiolactone (10 µM), the activities of astrocytic ETC complex I, II-III and IV were found to be comparable to control levels. In addition, the extracellular lactate:pyruvate ratio and the intracellular glutathione status of primary rat astrocytes were not significantly different between Hcy (200 or 500 µM) treated and controls. In conclusion, the results of this study suggest that Hcy induced impairment of astrocytic ETC function may not contribute to the pathophysiology of hyperhomocystinaemia.

  6. Quercetin Decreases Insulin Resistance in a Polycystic Ovary Syndrome Rat Model by Improving Inflammatory Microenvironment.

    Science.gov (United States)

    Wang, Zhenzhi; Zhai, Dongxia; Zhang, Danying; Bai, Lingling; Yao, Ruipin; Yu, Jin; Cheng, Wen; Yu, Chaoqin

    2017-05-01

    Insulin resistance (IR) is a clinical feature of polycystic ovary syndrome (PCOS). Quercetin, derived from Chinese medicinal herbs such as hawthorn, has been proven practical in the management of IR in diabetes. However, whether quercetin could decrease IR in PCOS is unknown. This study aims to observe the therapeutic effect of quercetin on IR in a PCOS rat model and explore the underlying mechanism. An IR PCOS rat model was established by subcutaneous injection with dehydroepiandrosterone. The body weight, estrous cycle, and ovary morphology of the quercetin-treated rats were observed. Serum inflammatory cytokines were analyzed using enzyme-linked immunosorbent assay. In ovarian tissues, the expression of key genes involved in the inflammatory signaling pathway was detected through Western blot, real-time polymerase chain reaction, or immunohistochemistry. The nuclear translocation of nuclear factor κB (NF-κB) was also observed by immunofluorescence. The estrous cycle recovery rate of the insulin-resistant PCOS model after quercetin treatment was 58.33%. Quercetin significantly reduced the levels of blood insulin, interleukin 1β, IL-6, and tumor necrosis factor α. Quercetin also significantly decreased the granulosa cell nuclear translocation of NF-κB in the insulin-resistant PCOS rat model. The treatment inhibited the expression of inflammation-related genes, including the nicotinamide adenine dinucleotide phosphate oxidase subunit p22phox, oxidized low-density lipoprotein, and Toll-like receptor 4, in ovarian tissue. Quercetin improved IR and demonstrated a favorable therapeutic effect on the PCOS rats. The underlying mechanism of quercetin potentially involves the inhibition of the Toll-like receptor/NF-κB signaling pathway and the improvement in the inflammatory microenvironment of the ovarian tissue of the PCOS rat model.

  7. Induction of osteoarthritis by injecting monosodium iodoacetate into the patellofemoral joint of an experimental rat model.

    Science.gov (United States)

    Takahashi, Ikufumi; Matsuzaki, Taro; Kuroki, Hiroshi; Hoso, Masahiro

    2018-01-01

    This study aimed to investigate the histopathological changes in the patellofemoral joint using a rat model of osteoarthritis that was induced using monosodium iodoacetate, and to establish a novel model of patellofemoral osteoarthritis in a rat model using histopathological analysis. Sixty male rats were used. Osteoarthritis was induced through a single intra-articular injection of monosodium iodoacetate in both knee joints. Animals were equally divided into two experimental groups based on the monosodium iodoacetate dose: 0.2 mg and 1.0 mg. Histopathological changes in the articular cartilage of the patellofemoral joint and the infrapatellar fat pad were examined at 3 days, 1 week, 2 weeks, 4 weeks, 8 weeks, and 12 weeks after the monosodium iodoacetate injection. In the 1.0-mg group, the representative histopathological findings of osteoarthritis were observed in the articular cartilage of the patellofemoral joint over time. Additionally, the Osteoarthritis Research Society International scores of the patellofemoral joint increased over time. The synovitis scores of the infrapatellar fat pad in both groups were highest at 3 days, and then the values decreased over time. The fibrosis score of the infrapatellar fat pad in the 1.0-mg group increased with time, whereas the fibrosis score in the 0.2-mg group remained low. Representative histopathological findings of osteoarthritis were observed in the articular cartilage of the patellofemoral joint in a rat model of osteoarthritis induced using monosodium iodoacetate. With appropriate selection, this model may be regarded as an ideal patellofemoral osteoarthritis model.

  8. Analysis and modeling of electronic portal imaging exit dose measurements

    International Nuclear Information System (INIS)

    Pistorius, S.; Yeboah, C.

    1995-01-01

    In spite of the technical advances in treatment planning and delivery in recent years, it is still unclear whether the recommended accuracy in dose delivery is being achieved. Electronic portal imaging devices, now in routine use in many centres, have the potential for quantitative dosimetry. As part of a project which aims to develop an expert-system based On-line Dosimetric Verification (ODV) system we have investigated and modelled the dose deposited in the detector of a video based portal imaging system. Monte Carlo techniques were used to simulate gamma and x-ray beams in homogeneous slab phantom geometries. Exit doses and energy spectra were scored as a function of (i) slab thickness, (ii) field size and (iii) the air gap between the exit surface and the detector. The results confirm that in order to accurately calculate the dose in the high atomic number Gd 2 O 2 S detector for a range of air gaps, field sizes and slab thicknesses both the magnitude of the primary and scattered components and their effective energy need to be considered. An analytic, convolution based model which attempts to do this is proposed. The results of the simulation and the ability of the model to represent these data will be presented and discussed. This model is used to show that, after training, a back-propagation feed-forward cascade correlation neural network has the ability to identify and recognise the cause of, significant dosimetric errors

  9. The rat as a model for orthodontic tooth movement--a critical review and a proposed solution

    NARCIS (Netherlands)

    Ren, Yijin; Maltha, Jaap C; Kuijpers-Jagtman, Anne Marie

    2004-01-01

    The aims of this study were to perform a systematic review of the use of rats as a model for experimental tooth movement, to give a critical evaluation of the use of elastics as a force delivery system, and to describe a newly designed well-defined model for tooth movement in rats. The literature

  10. Modeling skin collimation using the electron pencil beam redefinition algorithm

    International Nuclear Information System (INIS)

    Chi, Pai-Chun M.; Hogstrom, Kenneth R.; Starkschall, George; Antolak, John A.; Boyd, Robert A.

    2005-01-01

    Skin collimation is an important tool for electron beam therapy that is used to minimize the penumbra when treating near critical structures, at extended treatment distances, with bolus, or using arc therapy. It is usually made of lead or lead alloy material that conforms to and is placed on patient surface. Presently, commercially available treatment-planning systems lack the ability to model skin collimation and to accurately calculate dose in its presence. The purpose of the present work was to evaluate the use of the pencil beam redefinition algorithm (PBRA) in calculating dose in the presence of skin collimation. Skin collimation was incorporated into the PBRA by terminating the transport of electrons once they enter the skin collimator. Both fixed- and arced-beam dose calculations for arced-beam geometries were evaluated by comparing them with measured dose distributions for 10- and 15-MeV beams. Fixed-beam dose distributions were measured in water at 88-cm source-to-surface distance with an air gap of 32 cm. The 6x20-cm 2 field (dimensions projected to isocenter) had a 10-mm thick lead collimator placed on the surface of the water with its edge 5 cm inside the field's edge located at +10 cm. Arced-beam dose distributions were measured in a 13.5-cm radius polystyrene circular phantom. The beam was arced 90 deg. (-45 deg. to +45 deg. ), and 10-mm thick lead collimation was placed at ±30 deg. . For the fixed beam at 10 MeV, the PBRA-calculated dose agreed with measured dose to within 2.0-mm distance to agreement (DTA) in the regions of high-dose gradient and 2.0% in regions of low dose gradient. At 15 MeV, the PBRA agreed to within a 2.0-mm DTA in the regions of high-dose gradient; however, the PBRA underestimated the dose by as much as 5.3% over small regions at depths less than 2 cm because it did not model electrons scattered from the edge of the skin collimation. For arced beams at 10 MeV, the agreement was 1-mm DTA in the high-dose gradient regions, and 2

  11. [The replacement therapy of rPTH(1-84) in established rat model of hypothyroidism].

    Science.gov (United States)

    Ding, Zhiwei; Li, Tiancheng; Liu, Yuhe; Xiao, Shuifang

    2015-12-01

    To investigate the replacement therapy of rPTH(1-84) (recombinant human parathyroid hormone (1-84)) to hypothyroidism in established rat model. Rat model of hypothyroidism was established by resecting parathyroids. A total of 30 rats with removal of parathyroids were divided into 6 groups randomly, 5 in each group, and applied respectively with saline injection (negative control group), calcitriol treatment (positive control group) and quadripartite PTH administration with dose of 20, 40, 80 and 160 µg/kg (experimental groups). Saline and rPTH(1-84) were injected subcutaneously daily. Calcitriol was gavaged once a day. Sham-operation was conducted in 5 rats of negative control group. To verify the authenticity of the rat model with hypothyroidism, the serum was insolated centrifugally from rat blood that was obtained from angular vein at specific time to measure calcium and phosphorus concentration. Urine in 12 hours was collected by metabolic cages and the calcium concentration was measured. After 10-week drug treatment, the experiment was terminated and bilateral femoral bone and L2-5 lumbar vertebra were removed from rats. Bone mineral density (BMD)of bilateral femoral bone and lumbar vertebra was analyzed by dual X-ray absorptiometry (DXA). The concentration of bone alkaline phosphatase (BALP) in serum was determined by radioimmunoassay. The rat model with hypothyroidism was obtained by excising parathyroid gland and was verified by monitoring calcium and phosphorus concentration subsequently. Administration of rPTH(1-84) in the dose of 80 or 160 µg/kg made serum calcium and phosphorus back to normal levels, with no significant difference between the doses (P>0.05). The BMD in each group of rats with rPTH(1-84) administration was increased significantly (P0.05). Calcium and phosphorus return to normal level by administration of rPTH(1-84) in the dose of 80 µg/kg or 160 µg/kg, with increase in BMD. Calcitriol can return the level of calcium to normal and

  12. Ranitidine reduced levodopa-induced dyskinesia in a rat model of Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Cui G

    2013-12-01

    Full Text Available Guiyun Cui,1,* Xinxin Yang,1,* Xiaoying Wang,2,* Zunsheng Zhang,1 Xuanye Yue,1 Hongjuan Shi,1 Xia Shen11Department of Neurology, 2Department of Ultrasound, the Affiliated Hospital of Xuzhou Medical College, Jiangsu, People’s Republic of China *These authors contributed equally to this workBackground: Chronic administration of levodopa in Parkinson’s disease leads to debilitating involuntary movements, termed levodopa-induced dyskinesia (LID. The pathogenesis of LID is poorly understood. Previous research has shown that histamine H2 receptors are highly expressed in the input (striatum and output (globus pallidus, substantia nigra regions of the basal ganglia, particularly in the GABAergic striatopallidal and striatonigral pathways. Therefore, a histamine H2 receptor antagonist could be used to reduce LID. In the present work, we investigated whether ranitidine has the potential to diminish LID in rats with dyskinesia and explored the underlying mechanisms involved.Methods: A rat model of PD was induced by 6-hydroxydopamine. Valid PD rats were then treated with levodopa (25 mg/kg, intraperitoneally and benserazide (12.5 mg/kg, intraperitoneally for 21 days to induce a rat model of LID. The acute and chronic effects of administration of ranitidine at different doses (5 mg/kg, 10 mg/kg, and 20 mg/kg on abnormal involuntary movements, levodopa-induced rotations, and the forelimb adjusting steps test were investigated in LID rats. The chronic effect of ranitidine (10 mg/kg on the expression of Arc and proenkephalin was also evaluated.Results: Levodopa elicited increased dyskinesia in PD rats. Acute ranitidine treatment had no effect on LID, but chronic ranitidine administration (10 mg/kg, 20 mg/kg reduced LID in rats with dyskinesia. Importantly, levodopa-induced rotations were not affected by chronic treatment with ranitidine. In addition, chronic ranitidine (10 mg/kg, 20 mg/kg significantly improved stepping of the lesioned forepaw. Real

  13. Validation of infrared thermography in serotonin-induced itch model in rats

    DEFF Research Database (Denmark)

    Dagnæs-Hansen, Frederik; Jasemian, Yousef; Gazerani, Parisa

    The number of scratching bouts is generally used as a standard method in animal models of itch. The aim of the present study was to validate the application of infrared thermography (IR-Th) in a serotonin-induced itch model in rats. Adult Sprague-Dawley male rats (n = 24) were used in 3 consecutive...... experiments. The first experiment evaluated vasomotor response (IR-Th) and scratching behavior (number of bouts) induced by intradermal serotonin (10 μl, 2%). Isotonic saline (control: 10 μl, 0.9%) and Methysergide (antagonist: 10 μl, 0.047 mg/ml) were used. The second experiment evaluated the dose......-response effect of intradermal serotonin (1%, 2% and 4%) on local temperature. The third experiment evaluated the anesthetized rats to test the local vasomotor responses in absent of scratching. Serotonin elicited significant scratching and lowered the local temperature at the site of injection. A dose...

  14. Avastin exhibits therapeutic effects on collagen-induced arthritis in rat model.

    Science.gov (United States)

    Wang, Yong; Da, Gula; Li, Hongbin; Zheng, Yi

    2013-12-01

    Avastin is the monoclonal antibody for vascular endothelial growth factor (VEGF). This study aimed to investigate therapeutic effect of Avastin on type II collagen-induced arthritis. Type II chicken collagen was injected into the tails of Wistar rats, and 60 modeled female rats were randomly divided into three groups (n = 20): Avastin group, Etanercept group, and control group. Arthritis index and joint pad thickness were scored, and the pathology of back metapedes was analyzed. The results showed that compared to control group, the arthritis index, target-to-non-target ratio, synovial pathological injury index, serum levels of VEGF and tumor necrosis factor alpha, and VEGF staining were decreased significantly 14 days after Avastin or Etanercept treatment, but there were no significant differences between Avastin group and Etanercept group. These data provide evidence that Avastin exhibits similar effects to Etanercept to relieve rheumatoid arthritis in rat model and suggest that Avastin is a promising therapeutic agent for rheumatoid arthritis.

  15. Transplantation of ES cells to Parkinson model rat irradiated with carbon ion beam

    International Nuclear Information System (INIS)

    Inaji, Motoki; Okauchi, Takashi; Nagai, Yuji; Nojima, Kumie; Suhara, Tetsuya

    2004-01-01

    The present study was designed to make a new Parkinson disease model using carbon ion beam. In this year, we irradiated right middle forebrain bundle of adult rats with charged carbon particles (290 MeV/nucleon, Mono peak, 150 Gy) and damaged right dopaminergic neurons pathway. To irradiate precisely, rats were set in the stereotactic frame with ear bars which was developed in this year. In 4 weeks after the irradiation, we performed methamphetamine induced rotation test and the autoradiography measurement on dopamine transporter using [ 11 C]PE2I to assess degeneration of dopaminergic neurons in caudate putamen (Cpu). As a result, ipsilateral rotation was observed and the distributions of dopamine transporter in the striatum decreased significantly. These results are similar to those of 6-OHDA lesioned rats, and indicate validity of this model. (author)

  16. Skeletal growth and long-term bone turnover after enterocystoplasty in a chronic rat model

    DEFF Research Database (Denmark)

    Gerharz, E.W.; Gasser, J.A.; Mosekilde, Li.

    2003-01-01

    OBJECTIVE: To investigate skeletal growth and bone metabolism in a chronic animal model of urinary diversion.MATERIALS AND METHODS: Young male Wistar rats (120) were allocated randomly to four groups undergoing: ileocystoplasty, ileocystoplasty and resection of the ileocaecal segment, colocystopl......OBJECTIVE: To investigate skeletal growth and bone metabolism in a chronic animal model of urinary diversion.MATERIALS AND METHODS: Young male Wistar rats (120) were allocated randomly to four groups undergoing: ileocystoplasty, ileocystoplasty and resection of the ileocaecal segment......, colocystoplasty, and controls. All animals received antibiotics for 1 week after surgery; half of each group remained on oral antibiotics. Bone-related biochemistry was measured in serum and urine. Dual-energy X-ray absorptiometry and peripheral quantitative computed tomography (pQCT) were used to determine bone...... no differences in bone length and volume. Loss of bone mass was almost exclusively in rats with ileocystoplasty and resection of the ileocaecal segment (-37.5%, pQCT, P

  17. A rat model of hypohidrotic ectodermal dysplasia carries a missense mutation in the Edaradd gene

    Science.gov (United States)

    2011-01-01

    Background Hypohidrotic ectodermal dysplasia (HED) is a congenital disorder characterized by sparse hair, oligodontia, and inability to sweat. It is caused by mutations in any of three Eda pathway genes: ectodysplasin (Eda), Eda receptor (Edar), and Edar-associated death domain (Edaradd), which encode ligand, receptor, and intracellular adaptor molecule, respectively. The Eda signaling pathway activates NF-κB, which is central to ectodermal differentiation. Although the causative genes and the molecular pathway affecting HED have been identified, no curative treatment for HED has been established. Previously, we found a rat spontaneous mutation that caused defects in hair follicles and named it sparse-and-wavy (swh). Here, we have established the swh rat as the first rat model of HED and successfully identified the swh mutation. Results The swh/swh rat showed sparse hair, abnormal morphology of teeth, and absence of sweat glands. The ectoderm-derived glands, meibomian, preputial, and tongue glands, were absent. We mapped the swh mutation to the most telomeric part of rat Chr 7 and found a Pro153Ser missense mutation in the Edaradd gene. This mutation was located in the death domain of EDARADD, which is crucial for signal transduction and resulted in failure to activate NF-κB. Conclusions These findings suggest that swh is a loss-of-function mutation in the rat Edaradd and indicate that the swh/swh rat would be an excellent animal model of HED that could be used to investigate the pathological basis of the disease and the development of new therapies. PMID:22013926

  18. A New Rat Model of Epileptic Spasms Based on Methylazoxymethanol-Induced Malformations of Cortical Development

    Directory of Open Access Journals (Sweden)

    Eun-Hee Kim

    2017-06-01

    Full Text Available Malformations of cortical development (MCDs can cause medically intractable epilepsies and cognitive disabilities in children. We developed a new model of MCD-associated epileptic spasms by treating rats prenatally with methylazoxymethanol acetate (MAM to induce cortical malformations and postnatally with N-methyl-d-aspartate (NMDA to induce spasms. To produce cortical malformations to infant rats, two dosages of MAM (15 mg/kg, intraperitoneally were injected to pregnant rats at gestational day 15. In prenatally MAM-exposed rats and the controls, spasms were triggered by single (6 mg/kg on postnatal day 12 (P12 or 10 mg/kg on P13 or 15 mg/kg on P15 or multiple doses (P12, P13, and P15 of NMDA. In prenatally MAM-exposed rats with single NMDA-provoked spasms at P15, we obtain the intracranial electroencephalography and examine the pretreatment response to adrenocorticotropic hormone (ACTH or vigabatrin. Rat pups prenatally exposed to MAM exhibited a significantly greater number of spasms in response to single and multiple postnatal NMDA doses than vehicle-exposed controls. Vigabatrin treatment prior to a single NMDA dose on P15 significantly suppressed spasms in MAM group rats (p < 0.05, while ACTH did not. The MAM group also showed significantly higher fast oscillation (25–100 Hz power during NMDA-induced spasms than controls (p = 0.047. This new model of MCD-based epileptic spasms with corresponding features of human spasms will be valuable for future research of the developmental epilepsy.

  19. Cyclosporin A significantly improves preeclampsia signs and suppresses inflammation in a rat model.

    Science.gov (United States)

    Hu, Bihui; Yang, Jinying; Huang, Qian; Bao, Junjie; Brennecke, Shaun Patrick; Liu, Huishu

    2016-05-01

    Preeclampsia is associated with an increased inflammatory response. Immune suppression might be an effective treatment. The aim of this study was to examine whether Cyclosporin A (CsA), an immunosuppressant, improves clinical characteristics of preeclampsia and suppresses inflammation in a lipopolysaccharide (LPS) induced preeclampsia rat model. Pregnant rats were randomly divided into 4 groups: group 1 (PE) rats each received LPS via tail vein on gestational day (GD) 14; group 2 (PE+CsA5) rats were pretreated with LPS (1.0 μg/kg) on GD 14 and were then treated with CsA (5mg/kg, ip) on GDs 16, 17 and 18; group 3 (PE+CsA10) rats were pretreated with LPS (1.0 μg/kg) on GD 14 and were then treated with CsA (10mg/kg, ip) on GDs 16, 17 and 18; group 4 (pregnant control, PC) rats were treated with the vehicle (saline) used for groups 1, 2 and 3. Systolic blood pressure, urinary albumin, biometric parameters and the levels of serum cytokines were measured on day 20. CsA treatment significantly reduced LPS-induced systolic blood pressure and the mean 24-h urinary albumin excretion. Pro-inflammatory cytokines IL-6, IL-17, IFN-γ and TNF-α were increased in the LPS treatment group but were reduced in (LPS+CsA) group (Ppreeclampsia signs and attenuated inflammatory responses in the LPS induced preeclampsia rat model which suggests that immunosuppressant might be an alternative management option for preeclampsia. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Neuroprotective effect of curcumin in an experimental rat model of subarachnoid hemorrhage.

    Science.gov (United States)

    Kuo, Chang-Po; Lu, Chueng-He; Wen, Li-Li; Cherng, Chen-Hwan; Wong, Chih-Shung; Borel, Cecil O; Ju, Da-Tong; Chen, Chun-Mei; Wu, Ching-Tang

    2011-12-01

    Subarachnoid hemorrhage (SAH) causes a high mortality rate and morbidity. It was suggested that oxidant stress plays an important role in neuronal injury after SAH. Therefore, we assessed the effect of curcumin on reducing cerebral vasospasm and neurologic injury in a SAH model in rat. A double-hemorrhage model was used to induce SAH in rats. Groups of animals were treated with intraperitoneal injection of 20 mg/kg curcumin (curcumin group, n = 24) or dimethyl sulfoxide (vehicle group, n = 33), normal saline (SAH group, n = 34) or normal saline (sham group, n = 22), 3 h after SAH induction and daily for 6 days. Glutamate was measured before SAH induction and once daily for 7 days. Glutamate transporter-1, wall thickness and the perimeter of the basilar artery, neurologic scores, neuronal degeneration, malondialdehyde, superoxide dismutase, and catalase activities were assessed. Changes of glutamate levels were lower in the curcumin group versus the SAH and vehicle groups, especially on day 1 (56 folds attenuation vs. vehicle). Correspondingly, glutamate transporter-1 was preserved after SAH in curcumin-treated rats. In the hippocampus and the cortex, malondialdehyde was attenuated (30% and 50%, respectively). Superoxide dismutase (35% and 64%) and catalase (34% and 38%) activities were increased in the curcumin rats compared with the SAH rats. Mortality rate (relative risk: 0.59), wall thickness (30%) and perimeter (31%) of the basilar artery, neuron degeneration scores (39%), and neurologic scores (31%) were improved in curcumin-treated rats. Curcumin in multiple doses is effective against glutamate neurotoxicity and oxidative stress and improves the mortality rate in rats with SAH.

  1. Possible mechanism of PNS protection against cisplatin-induced nephrotoxicity in rat models.

    Science.gov (United States)

    Liu, Xinwen; Huang, Zhenguang; Zou, Xiaoqin; Yang, Yufang; Qiu, Yue; Wen, Yan

    2015-01-01

    This study investigates the mechanism of the protective effect of Panax notoginsenosides (PNS) against cisplatin-induced nephrotoxicity via the hypoxia inducible factor 1 (HIF-1)/Bcl-2/adenovirus E1B 19 kDa-interacting protein 3 (BNIP3) pathway of autophagy. The rats underwent intraperitoneal injection with a single dose of cisplatin and a subset of rats were also intraperitoneally injected with 31.35 mg/kg PNS once a day. After 24 h exposure to cisplatin, the concentrations of urinary N-acetyl-β-D-glucosaminidase (NAG), blood urea nitrogen (BUN) and serum creatinine (Scr) were determined. The rat renal tissue was examined using H&E-staining, and the mitochondria of renal tubular epithelial cells were observed using transmission electron microscopy. The expressions of microtubule-associated protein-1 light chain (LC)3, autophagy-related gene (Atg)5, Beclin-1 and BNIP3 in rat renal tissue were detected using western blotting. The expression of HIF-1 was detected by immunohistochemistry. The results showed that PNS significantly protected against cisplatin-induced nephrotoxicity, as evidenced by decreasing the concentration of blood BUN and Scr, the attenuation of renal histopathological changes and the mitochondrial damages of renal cells, and the increase of mitochondria autophagosome in renal tubular epithelial cells. Additionally, PNS significantly increased the expression of LC3 and the ratio of LC3II/LC3I in rat renal tissue. Moreover, PNS significantly increased the expression of HIF-1α, BNIP3, Atg5 and Beclin-1 in rat renal tissue. In conclusion, the protective effect of PNS on cisplatin-induced nephrotoxicity was mainly due to its ability to enhancing the mitochondrial autophagy of renal tissue via the HIF-1α/BNIP3 pathway, and here is the first demonstration about it.

  2. A Model of Electron-Positron Pair Formation

    Directory of Open Access Journals (Sweden)

    Lehnert B.

    2008-01-01

    Full Text Available The elementary electron-positron pair formation process is consideredin terms of a revised quantum electrodynamic theory, with specialattention to the conservation of energy, spin, and electric charge.The theory leads to a wave-packet photon model of narrow line widthand needle-radiation properties, not being available from conventionalquantum electrodynamics which is based on Maxwell's equations. Themodel appears to be consistent with the observed pair productionprocess, in which the created electron and positron form two raysthat start within a very small region and have original directionsalong the path of the incoming photon. Conservation of angular momentum requires the photon to possess a spin, as given by the present theory but not by the conventional one. The nonzero electric field divergence further gives rise to a local intrinsic electric charge density within the photon body, whereas there is a vanishing total charge of the latter. This may explain the observed fact that the photon decays on account of the impact from an external electric field. Such a behaviour should not become possible for a photon having zero local electric charge density.

  3. Modeling of the response under radiation of electronic dosemeters

    International Nuclear Information System (INIS)

    Menard, S.

    2003-01-01

    The simulation with with calculation codes the interactions and the transport of primary and secondary radiations in the detectors allows to reduce the number of developed prototypes and the number of experiments under radiation. The simulation makes possible the determination of the response of the instrument for exposure configurations more extended that these ones of references radiations produced in laboratories. The M.C.N.P.X. allows to transport, over the photons, electrons and neutrons, the charged particles heavier than the electrons and to simulate the radiation - matter interactions for a certain number of particles. The present paper aims to present the interest of the use of the M.C.N.P.X. code in the study, research and evaluation phases of the instrumentation necessary to the dosimetry monitoring. To do that the presentation gives the results of the modeling of a prototype of a equivalent tissue proportional counter (C.P.E.T.) and of the C.R.A.M.A.L. ( radiation protection apparatus marketed by the Eurisys Mesures society). (N.C.)

  4. A proposed model of e-trust for electronic banking

    Directory of Open Access Journals (Sweden)

    Neda Yousefi

    2015-11-01

    Full Text Available Customer’s trust is the most important and one of the key factors of success in e-commerce. However, trust is the essential aspects of e-banking adoption and the main element for building long-term relationships with the bank's customers. So the purpose of this research is to investigate the factors influencing on customer′s trust in e-banking services and prioritize them. Therefore, designed questionnaire was distributed among 177 electronic service customers in number of banks in the city of Karaj, Iran. Likert quintuplet scales were used to measure the variables. After collecting the questionnaires, the data were analyzed by structural equation modeling (by using LISREL 8.5. The results revealed that quality of electronic services such as ease of use, privacy and security, individual characteristics of customers such as disposition to trust and features of bank such as reputation, size and dependence on government, have had the greatest effect on customer′s trust in e-banking services.

  5. Monte Carlo modeling of ion beam induced secondary electrons

    Energy Technology Data Exchange (ETDEWEB)

    Huh, U., E-mail: uhuh@vols.utk.edu [Biochemistry & Cellular & Molecular Biology, University of Tennessee, Knoxville, TN 37996-0840 (United States); Cho, W. [Electrical and Computer Engineering, University of Tennessee, Knoxville, TN 37996-2100 (United States); Joy, D.C. [Biochemistry & Cellular & Molecular Biology, University of Tennessee, Knoxville, TN 37996-0840 (United States); Center for Nanophase Materials Science, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

    2016-09-15

    Ion induced secondary electrons (iSE) can produce high-resolution images ranging from a few eV to 100 keV over a wide range of materials. The interpretation of such images requires knowledge of the secondary electron yields (iSE δ) for each of the elements and materials present and as a function of the incident beam energy. Experimental data for helium ions are currently limited to 40 elements and six compounds while other ions are not well represented. To overcome this limitation, we propose a simple procedure based on the comprehensive work of Berger et al. Here we show that between the energy range of 10–100 keV the Berger et al. data for elements and compounds can be accurately represented by a single universal curve. The agreement between the limited experimental data that is available and the predictive model is good, and has been found to provide reliable yield data for a wide range of elements and compounds. - Highlights: • The Universal ASTAR Yield Curve was derived from data recently published by NIST. • IONiSE incorporated with the Curve will predict iSE yield for elements and compounds. • This approach can also handle other ion beams by changing basic scattering profile.

  6. Orthotopic model of canine osteosarcoma in athymic rats for evaluation of stereotactic radiotherapy.

    Science.gov (United States)

    Schwartz, Anthony L; Custis, James T; Harmon, Joseph F; Powers, Barbara E; Chubb, Laura S; LaRue, Susan M; Ehrhart, Nicole P; Ryan, Stewart D

    2013-03-01

    To develop an orthotopic model of canine osteosarcoma in athymic rats as a model for evaluating the effects of stereotactic radiotherapy (SRT) on osteosarcoma cells. 26 athymic nude rats. 3 experiments were performed. In the first 2 experiments, rats were injected with 1 × 10(6) Abrams canine osteosarcoma cells into the proximal aspect of the tibia (n = 12) or distal aspect of the femur (6). Tumor engraftment and progression were monitored weekly via radiography, luciferase imaging, and measurement of urine pyridinoline concentration for 5 weeks and histologic evaluation after euthanasia. In the third experiment, 8 rats underwent canine osteosarcoma cell injection into the distal aspect of the femur and SRT was administered to the affected area in three 12-Gy fractions delivered on consecutive days (total radiation dose, 36 Gy). Percentage tumor necrosis and urinary pyridinoline concentrations were used to assess local tumor control. The short-term effect of SRT on skin was also evaluated. Tumors developed in 10 of 12 tibial sites and all 14 femoral sites. Administration of SRT to rats with femoral osteosarcoma was feasible and successful. Mean tumor necrosis of 95% was achieved histologically, and minimal adverse skin effects were observed. The orthotopic model of canine osteosarcoma in rats developed in this study was suitable for evaluating the effects of local tumor control and can be used in future studies to evaluate optimization of SRT duration, dose, and fractionation schemes. The model could also allow evaluation of other treatments in combination with SRT, such as chemotherapy or bisphosphonate, radioprotectant, or parathyroid hormone treatment.

  7. Studies on the pathogenicity of anaerobes, especially Prevotella bivia, in a rat pyometra model.

    Science.gov (United States)

    Mikamo, H; Kawazoe, K; Izumi, K; Watanabe, K; Ueno, K; Tamaya, T

    1998-01-01

    OBJECTIVE: Prevotella bivia is one of the anaerobic bacteria that resides in the flora of the female genital tract. We studied the pathogenicity of P. bivia in a rat pyometra model. METHODS: The experimental animal (rat) model of pyometra was developed to investigate the pathogenicity of P. bivia in a rat pyometra model. RESULTS: In the groups inoculated with aerobes alone, the infection rate was 10% (1/10) in the Staphylococcus aureus- or Staphylococcus agalactiae-inoculated group and 20% (2/10) in the Escherichia coli-inoculated group. Infection was not established in the groups inoculated with anaerobes alone. High infection rates were observed in all the mixed-infection groups. In the S. agalactiae- and Bacteroides fragilis-, S. agalactiae- and P. bivia-, F. coli- and B. fragilis-, and E. coli- and P. bivia-inoculated groups, an infection rate of 100% (10/10) was demonstrated. The efficacy of antibiotics such as flomoxef (FMOX) could be determined using a rat pyometra model. In relation to the alteration of vaginal microbial flora during the menstrual cycle, estrogen increased the growth of P. bivia. CONCLUSION: Mixture of aerobic bacteria and P. bivia increased the pathogenicity of P. bivia. Estrogen would be useful for raising up the inflammatory change of the uterus in experimental models of genital tract infection due to P. bivia. PMID:9702587

  8. Depressive-like symptoms in a reserpine-induced model of fibromyalgia in rats.

    Science.gov (United States)

    Blasco-Serra, Arantxa; Escrihuela-Vidal, Francesc; González-Soler, Eva M; Martínez-Expósito, Fernando; Blasco-Ausina, M Carmen; Martínez-Bellver, Sergio; Cervera-Ferri, Ana; Teruel-Martí, Vicent; Valverde-Navarro, Alfonso A

    2015-11-01

    Since the pathogenesis of fibromyalgia is unknown, treatment options are limited, ineffective and in fact based on symptom relief. A recently proposed rat model of fibromyalgia is based on central depletion of monamines caused by reserpine administration. This model showed widespread musculoskeletal pain and depressive-like symptoms, but the methodology used to measure such symptoms has been criticized. Evidence relates the high prevalence of pain and depression in fibromyalgia to common pathogenic pathways, most probably focused on the monoaminergic system. The present study aims at a validation of the reserpine model of fibromyalgia. For this purpose, rats undergoing this model have been tested for depressive-like symptoms with a Novelty-Suppressed Feeding Test adaptation. Animals administered with reserpine and subjected to forced food deprivation performed a smaller number of incursions to the center of the open field, evidenced by a decrease in the per-minute rate of the rats' approaching, smelling or touching the food. They also took more time to eat from the central food than control rats. These NSFT findings suggest the presence of depressive-like disorders in this animal model of fibromyalgia. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Small Animal Models for Human Metapneumovirus: Cotton Rat is More Permissive than Hamster and Mouse

    Science.gov (United States)

    Zhang, Yu; Niewiesk, Stefan; Li, Jianrong

    2014-01-01

    Human metapneumovirus (hMPV) is the second most prevalent causative agent of pediatric respiratory infections worldwide. Currently, there are no vaccines or antiviral drugs against this virus. One of the major hurdles in hMPV research is the difficulty to identify a robust small animal model to accurately evaluate the efficacy and safety of vaccines and therapeutics. In this study, we compared the replication and pathogenesis of hMPV in BALB/c mice, Syrian golden hamsters, and cotton rats. It was found that BALB/c mice are not permissive for hMPV infection despite the use of a high dose (6.5 log10 PFU) of virus for intranasal inoculation. In hamsters, hMPV replicated efficiently in nasal turbinates but demonstrated only limited replication in lungs. In cotton rats, hMPV replicated efficiently in both nasal turbinate and lung when intranasally administered with three different doses (4, 5, and 6 log10 PFU) of hMPV. Lungs of cotton rats infected by hMPV developed interstitial pneumonia with mononuclear cells infiltrates and increased lumen exudation. By immunohistochemistry, viral antigens were detected at the luminal surfaces of the bronchial epithelial cells in lungs. Vaccination of cotton rats with hMPV completely protected upper and lower respiratory tract from wildtype challenge. The immunization also elicited elevated serum neutralizing antibody. Collectively, these results demonstrated that cotton rat is a robust small animal model for hMPV infection. PMID:25438015

  10. The Establishment of Metabolic Syndrome Model by Induction of Fructose Drinking Water in Male Wistar Rats

    Directory of Open Access Journals (Sweden)

    Norshalizah Mamikutty

    2014-01-01

    Full Text Available Background. Metabolic syndrome can be caused by modification of diet by means of consumption of high carbohydrate and high fat diet such as fructose. Aims. To develop a metabolic syndrome rat model by induction of fructose drinking water (FDW in male Wistar rats. Methods. Eighteen male Wistar rats were fed with FDW 20% and FDW 25% for a duration of eight weeks. The physiological changes with regard to food and fluid intake, as well as calorie intake, were measured. The metabolic changes such as obesity, dyslipidaemia, hypertension, and hyperglycaemia were determined. Data was presented in mean ± SEM subjected to one-way ANOVA. Results. Male Wistar rats fed with FDW 20% for eight weeks developed significant higher obesity parameters compared to those fed with FDW 25%. There was hypertrophy of adipocytes in F20 and F25. There were also systolic hypertension, hypertriglyceridemia, and hyperglycemia in both groups. Conclusion. We conclude that the metabolic syndrome rat model is best established with the induction of FDW 20% for eight weeks. This was evident in the form of higher obesity parameter which caused the development of the metabolic syndrome.

  11. New Wistar Kyoto and spontaneously hypertensive rat transgenic models with ubiquitous expression of green fluorescent protein

    Directory of Open Access Journals (Sweden)

    Ana Isabel Garcia Diaz

    2016-04-01

    Full Text Available The Wistar Kyoto (WKY rat and the spontaneously hypertensive (SHR rat inbred strains are well-established models for human crescentic glomerulonephritis (CRGN and metabolic syndrome, respectively. Novel transgenic (Tg strains add research opportunities and increase scientific value to well-established rat models. We have created two novel Tg strains using Sleeping Beauty transposon germline transgenesis, ubiquitously expressing green fluorescent protein (GFP under the rat elongation factor 1 alpha (EF1a promoter on the WKY and SHR genetic backgrounds. The Sleeping Beauty system functioned with high transgenesis efficiency; 75% of new rats born after embryo microinjections were transgene positive. By ligation-mediated PCR, we located the genome integration sites, confirming no exonic disruption and defining a single or low copy number of the transgenes in the new WKY-GFP and SHR-GFP Tg lines. We report GFP-bright expression in embryos, tissues and organs in both lines and show preliminary in vitro and in vivo imaging data that demonstrate the utility of the new GFP-expressing lines for adoptive transfer, transplantation and fate mapping studies of CRGN, metabolic syndrome and other traits for which these strains have been extensively studied over the past four decades.

  12. Porphyromonas gingivalis and Treponema denticola Mixed Microbial Infection in a Rat Model of Periodontal Disease

    Directory of Open Access Journals (Sweden)

    Raj K. Verma

    2010-01-01

    Full Text Available Porphyromonas gingivalis and Treponema denticola are periodontal pathogens that express virulence factors associated with the pathogenesis of periodontitis. In this paper we tested the hypothesis that P. gingivalis and T. denticola are synergistic in terms of virulence; using a model of mixed microbial infection in rats. Groups of rats were orally infected with either P. gingivalis or T. denticola or mixed microbial infections for 7 and 12 weeks. P. gingivalis genomic DNA was detected more frequently by PCR than T. denticola. Both bacteria induced significantly high IgG, IgG2b, IgG1, IgG2a antibody levels indicating a stimulation of Th1 and Th2 immune response. Radiographic and morphometric measurements demonstrated that rats infected with the mixed infection exhibited significantly more alveolar bone loss than shaminfected control rats. Histology revealed apical migration of junctional epithelium, rete ridge elongation, and crestal alveolar bone resorption; resembling periodontal disease lesion. These results showed that P. gingivalis and T. denticola exhibit no synergistic virulence in a rat model of periodontal disease.

  13. Neuroprotective and behavioral efficacy of intravenous transplanted adipose stem cells in experimental Parkinsonian rat models

    Directory of Open Access Journals (Sweden)

    Malihe Nakhaeifard

    2016-02-01

    Full Text Available Background: Parkinson's disease is a deficiency of dopamine in the striatum, characterized by bradykinesis, rigidity and resting tremor. Adipose tissue-Derived Stem Cells (ADSCs have many advantages for cell therapy because of the easy availability and pluripotency without ethical problems. In this research, the effects of ADSCs transplantation on motor impairment of rat Parkinsonian models were evaluated. Materials and Methods: Parkinson model was constructed by the unilateral lesion of striatum of male Wistar rats using 20µg of 6-hydroxydopamine (6-OHDA as lesion group. Cell and α-MEM (α-minimal essential medium groups were lesioned animals that received intravenous injection of 3×106 cells suspended in medium and medium repectively. All rats were evaluated behaviorally with rotarod and apomorphine-induced rotation tests, at 4 and 8 weeks after cell transplantation. Results: Lesion and α-MEM groups showed increased contralateral turns while cell group significantly ameliorated both in rotarod and apomorphine-induced rotation tests. There was a significant difference of contralateral turns between cell and lesioned groups at 8 weeks after transplantation. Lesioned rats showed significant decrease of staying on the rod as compared to control, but in cell group there was a significant increase in comparision with the lesioned animals. Conclusion: ADSCs injected intravenously promote functional recovery in Parkinsonian rats.

  14. Bifidobacterium breve prevents necrotising enterocolitis by suppressing inflammatory responses in a preterm rat model.

    Science.gov (United States)

    Satoh, T; Izumi, H; Iwabuchi, N; Odamaki, T; Namba, K; Abe, F; Xiao, J Z

    2016-02-01

    Necrotising enterocolitis (NEC) is associated with inflammatory responses and barrier dysfunction in the gut. In this study, we investigated the effect of Bifidobacterium breve M-16V on factors related to NEC development using an experimental rat model. Caesarean-sectioned rats were given formula milk with or without B. breve M-16V by oral gavage thrice daily, and experimental NEC was induced by exposing the rats to hypoxic conditions. Naturally delivered rats that were reared by their mother were used as healthy controls. The pathological score of NEC and the expression of molecules related to inflammatory responses and the barrier function were assessed in the ileum. B. breve M-16V reduced the pathological scores of NEC and resulted in some improvement in survivability. B. breve M-16V suppressed the increased expression of molecules related to inflammation and barrier function that resulted from NEC induction. B. breve M-16V normalised Toll-like receptor (TRL)4 expression and enhanced TLR2 expression. Our data suggest that B. breve M-16V prevents NEC development by modulating TLR expressions and suppressing inflammatory responses in a rat model.

  15. Skeletal growth and long-term bone turnover after enterocystoplasty in a chronic rat model

    DEFF Research Database (Denmark)

    Gerharz, E.W.; Gasser, J.A.; Mosekilde, Li.

    2003-01-01

    OBJECTIVE: To investigate skeletal growth and bone metabolism in a chronic animal model of urinary diversion.MATERIALS AND METHODS: Young male Wistar rats (120) were allocated randomly to four groups undergoing: ileocystoplasty, ileocystoplasty and resection of the ileocaecal segment, colocystopl......OBJECTIVE: To investigate skeletal growth and bone metabolism in a chronic animal model of urinary diversion.MATERIALS AND METHODS: Young male Wistar rats (120) were allocated randomly to four groups undergoing: ileocystoplasty, ileocystoplasty and resection of the ileocaecal segment...... mass ex vivo.RESULTS: Most (90%) of the rats survived the study period (8 months); six rats died from bowel obstruction at the level of the entero-anastomosis and four had to be killed because of persistent severe diarrhoea. Vital intestinal mucosa was found in all augmented bladders. There were...... no differences in bone length and volume. Loss of bone mass was almost exclusively in rats with ileocystoplasty and resection of the ileocaecal segment (-37.5%, pQCT, P

  16. In vivo micro-CT analysis of bone remodeling in a rat calvarial defect model

    Science.gov (United States)

    Umoh, Joseph U.; Sampaio, Arthur V.; Welch, Ian; Pitelka, Vasek; Goldberg, Harvey A.; Underhill, T. Michael; Holdsworth, David W.

    2009-04-01

    The rodent calvarial defect model is commonly used to investigate bone regeneration and wound healing. This study presents a micro-computed tomography (micro-CT) methodology for measuring the bone mineral content (BMC) in a rat calvarial defect and validates it by estimating its precision error. Two defect models were implemented. A single 6 mm diameter defect was created in 20 rats, which were imaged in vivo for longitudinal experiments. Three 5 mm diameter defects were created in three additional rats, which were repeatedly imaged ex vivo to determine precision. Four control rats and four rats treated with bone morphogenetic protein were imaged at 3, 6, 9 and 12 weeks post-surgery. Scan parameters were 80 kVp, 0.45 mA and 180 mAs. Images were reconstructed with an isotropic resolution of 45 µm. At 6 weeks, the BMC in control animals (4.37 ± 0.66 mg) was significantly lower (p small BMC changes in animals.

  17. Royal Jelly Prevents Osteoporosis in Rats: Beneficial Effects in Ovariectomy Model and in Bone Tissue Culture Model

    Directory of Open Access Journals (Sweden)

    Saburo Hidaka

    2006-01-01

    Full Text Available Royal jelly (RJ has been used worldwide for many years as medical products, health foods and cosmetics. Since RJ contains testosterone and has steroid hormone-type activities, we hypothesized that it may have beneficial effects on osteoporosis. We used both an ovariectomized rat model and a tissue culture model. Rats were divided into eight groups as follows: sham-operated (Sham, ovariectomized (OVX, OVX given 0.5% (w/w raw RJ, OVX given 2.0% (w/w RJ, OVX given 0.5% (w/w protease-treated RJ (pRJ, OVX given 2.0% (w/w pRJ, OVX given 17β-estradiol and OVX given its vehicle, respectively. The Ovariectomy decreased tibial bone mineral density (BMD by 24%. Administration of 17β-estradiol to OVX rats recovered the tibial BMD decrease by 100%. Administration of 2.0% (w/w RJ and 0.5–2.0% (w/w pRJ to OVX rats recovered it by 85% or more. These results indicate that both RJ and pRJ are almost as effective as 17β-estradiol in preventing the development of bone loss induced by ovariectomy in rats. In tissue culture models, both RJ and pRJ increased calcium contents in femoral-diaphyseal and femoral-metaphyseal tissue cultures obtained from normal male rats. However, in a mouse marrow culture model, they neither inhibited the parathyroid hormone (PTH-induced calcium loss nor affected the formation of osteoclast-like cells induced by PTH in mouse marrow culture system. Therefore, our results suggest that both RJ and pRJ may prevent osteoporosis by enhancing intestinal calcium absorption, but not by directly antagonizing the action of PTH.

  18. Evaluation of early changes induced by diuron in the rat urinary bladder using different processing methods for scanning electron microscopy.

    Science.gov (United States)

    Fava, Rafaela Marono; Ferragut Cardoso, Ana Paula; da Rocha, Mitscheli Sanches; Nascimento E Pontes, Merielen Garcia; de Camargo, João Lauro Viana; de Oliveira, Maria Luiza Cotrim Sartor

    2015-07-03

    Diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] is a substituted urea herbicide carcinogenic to the rat urinary bladder at high dietary levels. The suggested non-genotoxic mode of action (MOA) of diuron encompasses cytotoxicity and necrosis followed by regenerative hyperplasia. Prenecrotic swollen cells as observed under scanning electron microscopy (SEM) have been reported as early morphological alterations, putatively related to diuron cytotoxicity. However, these changes were not observed in a previous SEM study conducted in this laboratory. This study evaluated whether these early alterations are actually due to diuron cytotoxicity or artifacts related to different processing methods used for SEM analysis. Male Wistar rats were fed ad libitum with basal diet, 7.1% sodium saccharin (NaS) or 2.500ppm diuron for seven days or 15 weeks. The urinary bladders were processed for histological and labeling indices examinations and for SEM using two different processing methods. The incidence of simple hyperplasia after 15 weeks of exposure to diuron or to NaS was significantly increased. By SEM, the incidences and severity of lesions were significantly increased in the diuron group independently of exposure time. The different SEM processing methods used allowed for visualization of swollen superficial cells after seven days of diuron exposure. Probably the absence these cells in a previous study was due to the use very few animals. Our results support the hypothesis that the swollen cell is an early key event due to diuron-induced cytotoxicity and is the result of a degenerative process involved in the non-genotoxic carcinogenic mode of action of high doses of diuron. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Evaluation of early changes induced by diuron in the rat urinary bladder using different processing methods for scanning electron microscopy

    International Nuclear Information System (INIS)

    Fava, Rafaela Marono; Ferragut Cardoso, Ana Paula; Sanches da Rocha, Mitscheli; Nascimento e Pontes, Merielen Garcia; Viana de Camargo, João Lauro; Cotrim Sartor de Oliveira, Maria Luiza

    2015-01-01

    Diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] is a substituted urea herbicide carcinogenic to the rat urinary bladder at high dietary levels. The suggested non-genotoxic mode of action (MOA) of diuron encompasses cytotoxicity and necrosis followed by regenerative hyperplasia. Prenecrotic swollen cells as observed under scanning electron microscopy (SEM) have been reported as early morphological alterations, putatively related to diuron cytotoxicity. However, these changes were not observed in a previous SEM study conducted in this laboratory. This study evaluated whether these early alterations are actually due to diuron cytotoxicity or artifacts related to different processing methods used for SEM analysis. Male Wistar rats were fed ad libitum with basal diet, 7.1% sodium saccharin (NaS) or 2.500 ppm diuron for seven days or 15 weeks. The urinary bladders were processed for histological and labeling indices examinations and for SEM using two different processing methods. The incidence of simple hyperplasia after 15 weeks of exposure to diuron or to NaS was significantly increased. By SEM, the incidences and severity of lesions were significantly increased in the diuron group independently of exposure time. The different SEM processing methods used allowed for visualization of swollen superficial cells after seven days of diuron exposure. Probably the absence these cells in a previous study was due to the use very few animals. Our results support the hypothesis that the swollen cell is an early key event due to diuron-induced cytotoxicity and is the result of a degenerative process involved in the non-genotoxic carcinogenic mode of action of high doses of diuron

  20. Core-electron binding energies from self-consistent field molecular orbital theory using a mixture of all-electron real atoms and valence-electron model atoms

    International Nuclear Information System (INIS)

    Quinn, C.M.; Schwartz, M.E.

    1981-01-01

    The chemistry of large systems such as clusters may be readily investigated by valence-electron theories based on model potentials, but such an approach does not allow for the examination of core-electron binding energies which are commonly measured experimentally for such systems. Here we merge our previously developed Gaussian based valence-electron model potential theory with all-electron ab initio theory to allow for the calculation of core orbital binding energies when desired. For the atoms whose cores are to be examined, we use the real nuclear changes, all of the electrons, and the appropriate many-electron basis sets. For the rest of the system we use reduced nuclear charges, the Gaussian based model potentials, only the valence electrons, and appropriate valence-electron basis sets. Detailed results for neutral Al 2 are presented for the cases of all-electron, mixed real--model, and model--model SCF--MO calculations. Several different all-electron and valence electron calculations have been done to test the use of the model potential per se, as well as the effect of basis set choice. The results are in all cases in excellent agreement with one another. Based on these studies, a set of ''double-zeta'' valence and all-electron basis functions have been used for further SCF--MO studies on Al 3 , Al 4 , AlNO, and OAl 3 . For a variety of difference combinations of real and model atoms we find excellent agreement for relative total energies, orbital energies (both core and valence), and Mulliken atomic populations. Finally, direct core-hole-state ionic calculations are reported in detail for Al 2 and AlNO, and noted for Al 3 and Al 4 . Results for corresponding frozen-orbital energy differences, relaxed SCF--MO energy differences, and relaxation energies are in all cases in excellent agreement (never differing by more than 0.07 eV, usually by somewhat less). The study clearly demonstrates the accuracy of the mixed real--model theory

  1. Diagnostic PET Imaging of Mammary Microcalcifications Using 64Cu-DOTA-Alendronate in a Rat Model of Breast Cancer.

    Science.gov (United States)

    Ahrens, Bradley J; Li, Lin; Ciminera, Alexandra K; Chea, Junie; Poku, Erasmus; Bading, James R; Weist, Michael R; Miller, Marcia M; Colcher, David M; Shively, John E

    2017-09-01

    The development of improved breast cancer screening methods is hindered by a lack of cancer-specific imaging agents and effective small-animal models to test them. The purpose of this study was to evaluate 64 Cu-DOTA-alendronate as a mammary microcalcification-targeting PET imaging agent, using an ideal rat model. Our long-term goal is to develop 64 Cu-DOTA-alendronate for the detection and noninvasive differentiation of malignant versus benign breast tumors with PET. Methods: DOTA-alendronate was synthesized, radiolabeled with 64 Cu, and administered to normal or tumor-bearing aged, female, retired breeder Sprague-Dawley rats for PET imaging. Mammary tissues were subsequently labeled and imaged with light, confocal, and electron microscopy to verify microcalcification targeting specificity of DOTA-alendronate and elucidate the histologic and ultrastructural characteristics of the microcalcifications in different mammary tumor types. Tumor uptake, biodistribution, and dosimetry studies were performed to evaluate the efficacy and safety of 64 Cu-DOTA-alendronate. Results: 64 Cu-DOTA-alendronate was radiolabeled with a 98% yield. PET imaging using aged, female, retired breeder rats showed specific binding of 64 Cu-DOTA-alendronate in mammary glands and mammary tumors. The highest uptake of 64 Cu-DOTA-alendronate was in malignant tumors and the lowest uptake in benign tumors and normal mammary tissue. Confocal analysis with carboxyfluorescein-alendronate confirmed the microcalcification binding specificity of alendronate derivatives. Biodistribution studies revealed tissue alendronate concentrations peaking within the first hour, then decreasing over the next 48 h. Our dosimetric analysis demonstrated a 64 Cu effective dose within the acceptable range for clinical PET imaging agents and the potential for translation into human patients. Conclusion: 64 Cu-DOTA-alendronate is a promising PET imaging agent for the sensitive and specific detection of mammary tumors as

  2. Comprehensive Power Losses Model for Electronic Power Transformer

    DEFF Research Database (Denmark)

    Yue, Quanyou; Li, Canbing; Cao, Yijia

    2018-01-01

    and considering the impact of the non-unity power factor and the three-phase unbalanced current, the overall power losses in the distribution network when using the EPT to replace the conventional transformer is analyzed, and the conditions in which the application of the EPT can cause less power losses...... reduced power losses in the distribution network require a comprehensive consideration when comparing the power losses of theEPT and conventional transformer. In this paper, a comprehensive power losses analysis model for the EPT in distribution networks is proposed. By analyzing the EPT self-losses......The electronic power transformer (EPT) has highe rpower losses than the conventional transformer. However, the EPT can correct the power factor, compensate the unbalanced current and reduce the line power losses in the distribution network.Therefore, the higher losses of the EPT and the consequent...

  3. Electron localization in liquid hydrocarbons: The Anderson model

    International Nuclear Information System (INIS)

    Hug, Gordon L.; Mozumder, A.

    2008-01-01

    Anderson's model is applied for initial localization in liquid hydrocarbons (particularly n-alkanes) in conjunction with certain results of scaling theory. Medium connectivity is calculated using experimental X-ray data on liquid structure, from which critical disorder (W/V) c is computed, where W is diagonal disorder and V is the transfer energy. Actual W prevailing in the liquid is computed from anisotropic molecular polarizability. V is estimated by a heuristic procedure originating in scaling theory. These values are used to compute the percentage of initially delocalized states available for low-energy electrons in alkane liquids. This percentage decreases monotonically from methane (100%) to n-pentane and beyond (0%). In ethane and propane, the initial states are highly delocalized (97.6% and 83.9%, respectively). Subsequent trapping changes the situation as evidenced in mobility studies. Butane presents a partially, intermediate delocalized case (53.2%)

  4. Numerical model of electron cyclotron resonance ion source

    Directory of Open Access Journals (Sweden)

    V. Mironov

    2015-12-01

    Full Text Available Important features of the electron cyclotron resonance ion source (ECRIS operation are accurately reproduced with a numerical code. The code uses the particle-in-cell technique to model the dynamics of ions in ECRIS plasma. It is shown that a gas dynamical ion confinement mechanism is sufficient to provide the ion production rates in ECRIS close to the experimentally observed values. Extracted ion currents are calculated and compared to the experiment for a few sources. Changes in the simulated extracted ion currents are obtained with varying the gas flow into the source chamber and the microwave power. Empirical scaling laws for ECRIS design are studied and the underlying physical effects are discussed.

  5. Comprehensive Power Losses Model for Electronic Power Transformer

    DEFF Research Database (Denmark)

    Yue, Quanyou; Li, Canbing; Cao, Yijia

    2018-01-01

    The electronic power transformer (EPT) has highe rpower losses than the conventional transformer. However, the EPT can correct the power factor, compensate the unbalanced current and reduce the line power losses in the distribution network.Therefore, the higher losses of the EPT and the consequent...... reduced power losses in the distribution network require a comprehensive consideration when comparing the power losses of theEPT and conventional transformer. In this paper, a comprehensive power losses analysis model for the EPT in distribution networks is proposed. By analyzing the EPT self......-losses and considering the impact of the non-unity power factor and the three-phase unbalanced current, the overall power losses in the distribution network when using the EPT to replace the conventional transformer is analyzed, and the conditions in which the application of the EPT can cause less power losses...

  6. An Electron Microscopic Study of the Irradiation Effects on the Striated Duct Cells of the Submandibular Gland in Rats

    International Nuclear Information System (INIS)

    Lee, Kyu Chan; Lee, Sang Rae

    1990-01-01

    The purpose of this study was to investigate the effects of irradiation on the striated duct cells of the rat submandibular gland ductal tissues which control the characteristics of saliva. For this study, the experimental group was composed of 36 irradiated Sprague Dawley strain rats divided into 8 subgroups- 1 hour, 2 hours, 3 hours, 6 hours, 12 hours, 24 hours, 48 hours, 72 hours after irradiation. 4 non-irradiated rats were used as the control group. The experimental animals were singly irradiated with a dose of 18 Gy gamma ray to their head and neck region by the Co-6-teletherapy unit and sacrificed after each experimental duration. The specimens were examined with a light microscope with an H-E stain and with a transmission electron microscope. The results of this study were as follows. 1. In the light micrograph, a severe atrophic change occurred in the striated duct cells at 2 hours after irradiation and gradual recovery occurred from 6 hours after irradiation. 2. The nuclear chromosomes of the striated duct cells were changed granular at 2 hours after irradiation. Recovery was observed at 6 hours after irradiation. Nuclear bodies were also observed from 3 hours after irradiation. 3. The mitochondria of the striated duct cells had indistinct cristae at 2 hours after irradiation, and were degenerated or swollen at 3 hours after irradiation. They recovered, however, from 6 hours, with an increasing number at 48 hours a regular arrangement was observed at 72 hours after irradiation. 4. The microvilli showed atrophic changes at 2 hours after irradiation and were almost lost at 3 hours after irradiation. They were observed again from 48 hours after irradiation. 5. The rough endoplasmic reticulum and golgi body were not apparent at 1 hours after irradiation and were dilated with degeneration 2 hours after, but intact rough endoplasmic reticulum were observed from 3 hours after irradiation and developed well at 24 hours after irradiation. By the result of this

  7. Establishment of 9L/F344 rat intracerebral glioma model of brain tumor stem cells

    Directory of Open Access Journals (Sweden)

    Zong-yu XIAO

    2015-04-01

    Full Text Available Objective To establish the 9L/F344 rat intracerebral glioma model of brain tumor stem cells.  Methods Rat 9L gliosarcoma stem-like cells were cultured in serum-free suspension. The expression of CD133 and nestin were tested by immunohistochemistry. A total of 48 inbredline male F344 rats were randomly divided into 2 groups, and 9L tumor sphere cells and 9L monolayer cells were respectively implanted into the right caudate nucleus of F344 rats in 2 groups. Survival time was observed and determined using the method of Kaplan-Meier survival analysis. Fourteen days after implantation or when the rats were dying, their brains were perfused and sectioned for HE staining, and CD133 and nestin were detected by immunohistochemistry.  Results Rat 9L tumor spheres were formed with suspension culture in serum-free medium. The gliomas formed in both groups were invasive without obvious capsule. More new vessels, bleeding and necrosis could be detected in 9L tumor spheres group. The tumor cells in both groups were positive for CD133 and nestin. There was no significant difference in the expression of CD133 and nestin between 2 groups (P > 0.05, for all. According to the expression of nestin, the tumors formed by 9L tumor sphere cells were more invasive. The median survival time of the rats bearing 9L tumor sphere cells was 15 d (95%CI: 15.219-15.781, and the median survival time of the rats bearing 9L monolayer cells was 21 d (95%CI: 20.395-21.605. There was significant difference between 2 groups (χ2 = 12.800, P = 0.000.  Conclusions 9L/F344 rat intracerebral glioma model of brain tumor stem cells is successfully established, which provides a glioma model for the future research. DOI: 10.3969/j.issn.1672-6731.2015.04.012

  8. Thermal expansion model for multiphase electronic packaging materials

    International Nuclear Information System (INIS)

    Allred, B.E.; Warren, W.E.

    1991-01-01

    Control of thermal expansion is often necessary in the design and selection of electronic packages. In some instances, it is desirable to have a coefficient of thermal expansion intermediate between values readily attainable with single or two phase materials. The addition of a third phase in the form of fillers, whiskers, or fibers can be used to attain intermediate expansions. To help design the thermal expansion of multiphase materials for specific applications, a closed form model has been developed that accurately predicts the effective elastic properties of isotropic filled materials and transversely isotropic lamina. Properties of filled matrix materials are used as inputs to the lamina model to obtain the composite elastic properties as a function of the volume fraction of each phase. Hybrid composites with two or more fiber types are easily handled with this model. This paper reports that results for glass, quartz, and Kevlar fibers with beta-eucryptite filled polymer matrices show good agreement with experimental results for X, Y, and Z thermal expansion coefficients

  9. Intervention of Peiyuan Huayu Decoction on the neuron damage in model rats with acute subdural hematoma

    Directory of Open Access Journals (Sweden)

    Xiao-Xuan Fan

    2017-07-01

    Full Text Available Objective: To study the intervention effect of Peiyuan Huayu Decoction on the neuron damage in model rats with acute subdural hematoma (ASDH. Methods: 160 SD rats were randomly divided into four groups, and the ASDH model rats were made by stereotactic autoblood injection, and sham operation group received craniotomy without blood injection. Sham operation group and model group were normally bred after model establishment, and 6 h after model establishment, the treatment group received intragastric administration of Peiyuan Huayu Decoction, and control group received intragastric administration of Piracetam Tablets, 1 time a day. On the 1d, 3d, 5d and 7d after model establishment, the general conditions of rats (activity, food intake and mental state were observed, blood was collected via auricula dextra, ELISA method was used to determine peripheral plasma NSE and S100毬 protein contents, routine HE staining was conducted after perfusion fixation, the neurons in blood injection side of brain tissue were counted, and the neuron damage was observed. Results: 26 rats were dead in the experiment. The general conditions of sham operation group were significantly better than those of other groups, treatment group was significantly better than model group and control group on the 5d group (P0.05; neuron count of sham operation group was basically stable, treatment group was not different from model group and control group on the 1d (P>0.05, treatment group was better than model group (P0.05 on the 3d, and treatment group was better than model group and control group on the 5d and 7d (P0.05, S100毬 protein and NSE contents decreased significantly on the 3d, and treatment group was significantly different from model group and control group (P<0.05, S100毬 protein and NSE contents increased on the 5d and 7d, the increase in treatment group was slower than that in model group and control group, and there was significant difference (P<0.05. Conclusion

  10. Bisphenol A Induces Hepatotoxicity through Oxidative Stress in Rat Model

    Directory of Open Access Journals (Sweden)

    Zeinab K. Hassan

    2012-01-01

    Full Text Available Reactive oxygen species (ROS are cytotoxic agents that lead to significant oxidative damage. Bisphenol A (BPA is a contaminant with increasing exposure to it and exerts both toxic and estrogenic effects on mammalian cells. Due to limited information concerning the effect of BPA on liver, this study investigates whether BPA causes hepatotoxicity by induction of oxidative stress in liver. Rats were divided into five groups: The first four groups, BPA (0.1, 1, 10, 50 mg/kg/day were administrated orally to rats for four weeks. The fifth group was taken water with vehicle. The final body weights in the 0.1 mg group showed a significant decrease compared to control group. Significant decreased levels of reduced glutathione, superoxide dismutase, glutathione peroxidase, glutathione-S-transferase, glutathione reductase and catalase activity were found in the 50 mg BPA group compared to control groups. High dose of BPA (50 mg/kg significantly increased the biochemical levels of ALT, ALP and total bilirubin. BPA effect on the activity of antioxidant genes was confirmed by real time PCR in which the expression levels of these genes in liver tissue were significantly decrease compared to control. Data from this study demonstrate that BPA generate ROS and reduce the antioxidant gene expression that causes hepatotoxicity.

  11. Dynamic computed tomography (CT) in the rat kidney and application to acute renal failure models

    International Nuclear Information System (INIS)

    Ishikawa, Isao; Saito, Tadashi; Ishii, Hirofumi; Bansho, Junichi; Koyama, Yukinori; Tobita, Akira

    1995-01-01

    Renal dynamic CT scanning is suitable for determining the excretion of contrast medium in the cortex and medulla of the kidney, which is valuable for understanding the pathogenesis of disease processes in various conditions. This form of scanning would be convenient for use, if a method of application to the rat kidney were available. Therefore, we developed a method of applying renal dynamic CT to rats and evaluated the cortical and medullary curves, e.g., the corticomedullary junction time which is correlated to creatinine clearance, in various rat models of acute renal failure. The rat was placed in a 10deg oblique position and a bilateral hilar slice was obtained before and 5, 10, 15, 20, 25, 30, 40, 50, 60, 80, 100, 120, 140, 160 and 180 sec after administering 0.5 ml of contrast medium using Somatom DR. The width of the slice was 4 mm and the scan time was 3 sec. The corticomedullary junction time in normal rats was 23.0±10.5 sec, the peak value of the cortical curve was 286.3±76.7 Hounsfield Unit (HU) and the peak value of the medullary curve was 390.1±66.2 HU. Corticomedullary junction time after exposure of the kidney was prolonged compared to that of the unexposed kidney. In rats with acute renal failure, the excretion pattern of contrast medium was similar in both the glycerol- and HgCl2-induced acute renal failure models. The peak values of the cortical curve were maintained three hours after a clamp was placed at the hilar region of the kidney for one hour, and the peak values of the medullary curve were maintained during the administration of 10μg/kg/min of angiotensin II. Dynamic CT curves in the acute renal failure models examined were slightly different from those in human acute renal failure. These results suggest that rats do not provide an ideal model for human acute renal failure. However, the application of dynamic CT to the rat kidney models was valuable for estimating the pathogenesis of various human kidney diseases. (author)

  12. Models for the transport of low energy electrons in water and the yield of hydrated electrons at early times

    International Nuclear Information System (INIS)

    Brenner, D.J.; Miller, J.H.; Ritchie, R.H.; Bichsel, H.

    1985-01-01

    An insulator model with four experimental energy bands was used to fit the optical properties of liquid water and to extend these data to non-zero momentum transfer. Inelastic mean free paths derived from this dielectric response function provided the basic information necessary to degrade high energy electrons to the subexcitation energy domain. Two approaches for the transport of subexcitation electrons were investigated. (i) Gas phase cross sections were used to degrade subexcitation electrons to thermal energy and the thermalization lengths were scaled to unit density. (ii) Thermalization lengths were estimated by age-diffusion theory with a stopping power deduced from the data on liquid water and transport cross sections derived from elastic scattering in water vapor. Theoretical ranges were compared to recent experimental results. A stochastic model was used to calculate the rapid diffusion and reaction of hydrated electrons with other radiolysis products. The sensitivity of the calculated yields to the model assumptions and comparison with experimental data are discussed

  13. Attention and executive functions in a rat model of chronic epilepsy.

    Science.gov (United States)

    Faure, Jean-Baptiste; Marques-Carneiro, José E; Akimana, Gladys; Cosquer, Brigitte; Ferrandon, Arielle; Herbeaux, Karine; Koning, Estelle; Barbelivien, Alexandra; Nehlig, Astrid; Cassel, Jean-Christophe

    2014-05-01

    Temporal lobe epilepsy is a relatively frequent, invalidating, and often refractory neurologic disorder. It is associated with cognitive impairments that affect memory and executive functions. In the rat lithium-pilocarpine temporal lobe epilepsy model, memory impairment and anxiety disorder are classically reported. Here we evaluated sustained visual attention in this model of epilepsy, a function not frequently explored. Thirty-five Sprague-Dawley rats were subjected to lithium-pilocarpine status epilepticus. Twenty of them received a carisbamate treatment for 7 days, starting 1 h after status epilepticus onset. Twelve controls received lithium and saline. Five months later, attention was assessed in the five-choice serial reaction time task, a task that tests visual attention and inhibitory control (impulsivity/compulsivity). Neuronal counting was performed in brain regions of interest to the functions studied (hippocampus, prefrontal cortex, nucleus basalis magnocellularis, and pedunculopontine tegmental nucleus). Lithium-pilocarpine rats developed motor seizures. When they were able to learn the task, they exhibited attention impairment and a tendency toward impulsivity and compulsivity. These disturbances occurred in the absence of neuronal loss in structures classically related to attentional performance, although they seemed to better correlate with neuronal loss in hippocampus. Globally, rats that received carisbamate and developed motor seizures were as impaired as untreated rats, whereas those that did not develop overt motor seizures performed like controls, despite evidence for hippocampal damage. This study shows that attention deficits reported by patients with temporal lobe epilepsy can be observed in the lithium-pilocarpine model. Carisbamate prevents the occurrence of motor seizures, attention impairment, impulsivity, and compulsivity in a subpopulation of neuroprotected rats. Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.

  14. Chronic prostatic infection and inflammation by Propionibacterium acnes in a rat prostate infection model.

    Science.gov (United States)

    Olsson, Jan; Drott, Johanna Bergh; Laurantzon, Lovisa; Laurantzon, Oscar; Bergh, Anders; Elgh, Fredrik

    2012-01-01

    Chronic inflammation in the prostate, seen as infiltration of inflammatory cells into the prostate gland in histological samples, affects approximately half the male population without indication of prostate disease, and is almost ubiquitous in patients diagnosed with benign prostate hyperplasia and cancer. Several studies have demonstrated the gram-positive bacterium Propionibacterium acnes to be frequently present in prostate tissue from men suffering from prostate disease. P. acnes has been shown to be associated with histological inflammation in human prostatectomy specimens, and also to induce strong inflammatory response in prostate-derived tissue culture models. The present paper describes a rat model for assessment of the pathogenic potential of P. acnes in prostate. Prostate glands of Sprague Dawley rats (n = 98) were exposed via an abdominal incision and live P. acnes or, in control rats, saline were injected into the ventral and dorso-lateral lobes. Rats were sacrificed 5 days, 3 weeks, 3 months and 6 months post infection, and prostate tissue was analyzed for bacterial content and histological inflammation. Rat sera were assessed for levels of CRP and anti-P. acnes IgG. Live P. acnes could be recovered from the dorso-lateral lobes up to 3 months post infection, while the ventral lobes were cleared from bacteria at that time. In samples up to 3 months post infection, the dorso-lateral lobes exhibited intense focal inflammation. CRP and IgG levels were elevated throughout the span of the experiment, and reached maximum levels 3 weeks and 3 months post infection, respectively. We show that P. acnes have the potential to cause chronic infection in previously healthy prostate, and that the infection has potential to cause chronic histological inflammation in the infected tissue. The high prevalence of P. acnes in human prostate tissue calls for resolution of pathogenic details. The present rat model suggests that complications such as chronic

  15. Establishment and evaluation of a rat model of inhalation lung injury induced by ship smog

    Directory of Open Access Journals (Sweden)

    Xin-xin DUAN

    2018-03-01

    Full Text Available Objective To establish and evaluate a rat model of inhalation lung injury induced by ship smog. Methods A rat model of inhalation lung injury was established by analyzing the composition of ship materials after combustion. Forty- two healthy male Wistar rats were randomly divided into normal control group and 2, 6, 12, 24, 48 and 72h groups (6 eachafter inhalation, these rats were killed at each time point, and the changes of arterial blood gas, coagulation function, the lung water content (% were detected. Macroscopic and microscopic changes in lung tissues were observed to judge the degree of lung injury. Results The main components after combustion of 7 kinds of nonmetal materials on ship included CO, CO2, H2S, NOx and other harmful gases in this study, AIKE in one gas detector was used to monitor O2, CO, CO2 and H2S, and their concentrations remained relatively stable within 15 minutes, and the injury time was 15 minutes. The rats presented with shortness of breath and mouth breathing. Smoke inhalation caused a significant hypoxemia, the concentration of blood COHb reached a peak value 2h and the lung water content (% did 6h after inhalation (P<0.05. It is metabolic acidosis in the early stage after inhalation, but metabolic acidosis combined with respiratory acidosis in the later period. Histopathological observation showed diffuse hemorrhage, edema and inflammatory cell infiltration in the lung tissue as manifestations of lung injury, and the injury did not recover at 72h after inhalation, the change of blood coagulation function was not statistically significant. Conclusion A rat model of inhalation lung injury induced by ship smog has been successfully established, and has the advantages of easy replication, stability and reliability, thus can be used to research and treat inhalation lung injury induced by ship smog in naval war environment and other cases. DOI: 10.11855/j.issn.0577-7402.2018.03.14

  16. Dynamic modeling of renal blood flow in Dahl hypertensive and normotensive rats

    DEFF Research Database (Denmark)

    Knudsen, Torben; Elmer, Henrik; Knudsen, Morten H

    2004-01-01

    A method is proposed in this paper which allows characterization of renal autoregulatory dynamics and efficiency using quantitative mathematical methods. Based on data from rat experiments, where arterial blood pressure and renal blood flow are measured, a quantitative model for renal blood flow...

  17. Prevention of injury by resveratrol in a rat model of adenine-induced ...

    African Journals Online (AJOL)

    administration were analyzed using an auto-analyzer. Results: Resveratrol treatment significantly inhibited ... administration in a rat model of CKD by inhibiting FGF-23, parathyroid hormone, and phosphate. Thus, resveratrol may be of therapeutic ... FGF-23 also inhibits the generation of vitamin D and maintains the balance ...

  18. Strain Differences in Antioxidants in Rat Models of Cardiovascular Disease Exposed to Ozone

    Science.gov (United States)

    We examined the hypothesis that antioxidant substances and enzymes in lung, heart and in bronchoalveolar lavage fluid (BALF) are altered in response to 03 in cardiovascular disease and/or metabolic syndrome (CVD)-prone rat models. CVD strains [spontaneously hypertensive (SH), SH ...

  19. Selenium prevents tumor development in a rat model for chemical carcinogenesis

    DEFF Research Database (Denmark)

    Bjorkhem-Bergman, L.; Torndal, U. B.; Eken, S.

    2005-01-01

    Previous studies in animals and humans have shown that selenium compounds can prevent cancer development. In this work we studied the tumor preventive effect of selenium supplementation, administrated as selenite, in the initiation, promotion and progression phases in a synchronized rat model for...

  20. Atorvastatin treatment during epileptogenesis in a rat model for temporal lobe epilepsy

    NARCIS (Netherlands)

    van Vliet, Erwin A.; Holtman, Linda; Aronica, Eleonora; Schmitz, Leanne J. M.; Wadman, Wytse J.; Gorter, Jan A.

    2011-01-01

    Purpose: It has been shown that blood-brain barrier leakage together with inflammation could contribute to epileptogenesis and seizure progression in a rat model for temporal lobe epilepsy. Because statins have been shown to reduce blood-brain barrier permeability and inflammation in neurological

  1. Ocular Changes in TgF344-AD Rat Model of Alzheimer's Disease

    OpenAIRE

    Tsai, Yuchun; Lu, Bin; Ljubimov, Alexander V.; Girman, Sergey; Ross-Cisneros, Fred N.; Sadun, Alfredo A.; Svendsen, Clive N.; Cohen, Robert M.; Wang, Shaomei

    2014-01-01

    In this study, we observed pathological changes in the choroid and in RPE cells in the TgF344-AD rat model; choroidal thinning was further observed in human AD retina. Along with Aβ deposition, the inflammatory response was manifested by microglial recruitment and complement activation.

  2. Oxidative stress in a rat model of cotton smoke inhalation-induced ...

    African Journals Online (AJOL)

    Background: Smoke inhalation injury refers to airway and lung parenchyma injury and general chemical damage caused by inhaling toxic gases and substances. The aim of this study was to explore the oxidative stress mechanism of cotton smoke inhalation-induced pulmonary injury in a rat model. Materials and Methods: ...

  3. Validity of Quinpirole Sensitization Rat Model of OCD: Linking Evidence from Animal and Clinical Studie

    Czech Academy of Sciences Publication Activity Database

    Stuchlík, Aleš; Radostová, Dominika; Hatalová, Hana; Valeš, Karel; Nekovářová, Tereza; Kopřivová, J.; Svoboda, Jan; Horáček, J.

    2016-01-01

    Roč. 10, Oct 26 (2016), č. článku 209. ISSN 1662-5153 R&D Projects: GA MZd(CZ) NV15-34524A Institutional support: RVO:67985823 Keywords : OCD * quinpirole * animal model * brain circuits * rat * human Subject RIV: FH - Neurology Impact factor: 3.104, year: 2016

  4. Electrospun biodegradable microfibers induce new collagen formation in a rat abdominal wall defect model

    DEFF Research Database (Denmark)

    Tarpø, Cecilie Lærke Glindtvad; Chen, Menglin; Nygaard, Jens Vinge

    2018-01-01

    and effect on collagen and elastin production of a degradable mesh releasing basic fibroblast growth factor (bFGF). Implantation of biodegradable mesh with or without bFGF in their core has been conducted in 40 rats in an abdominal wall defect model. Samples were explanted after 4, 8, and 24 weeks...

  5. The Dilator Naris Muscle as a Reporter of Facial Nerve Regeneration in a Rat Model

    NARCIS (Netherlands)

    Weinberg, J.S.; Kleiss, I.J.; Knox, C.J.; Heaton, J.T.; Hadlock, T.A.

    2016-01-01

    OBJECTIVE: Many investigators study facial nerve regeneration using the rat whisker pad model, although widely standardized outcomes measures of facial nerve regeneration in the rodent have not yet been developed. The intrinsic whisker pad "sling" muscles producing whisker protraction, situated at

  6. Influence of fluid resuscitation on renal microvascular PO2 in a normotensive rat model of endotoxemia

    NARCIS (Netherlands)

    Johannes, Tanja; Mik, Egbert G.; Nohé, Boris; Raat, Nicolaas J. H.; Unertl, Klaus E.; Ince, Can

    2006-01-01

    INTRODUCTION: Septic renal failure is often seen in the intensive care unit but its pathogenesis is only partly understood. This study, performed in a normotensive rat model of endotoxemia, tests the hypotheses that endotoxemia impairs renal microvascular PO2 (microPO2) and oxygen consumption

  7. Assessment of visceral sensitivity using radio telemetry in a rat model of maternal separation

    NARCIS (Netherlands)

    Welting, O.; van den Wijngaard, R. M.; de Jonge, W. J.; Holman, R.; Boeckxstaens, G. E.

    2005-01-01

    Stress plays an important role in the development of visceral hypersensitivity, a key mechanism underlying the pathophysiology of the irritable bowel syndrome. Visceral sensitivity in rats is generally assessed under restrain conditions. To avoid this potential stress factor, we developed a model

  8. Brain scan in cerebral ischemia. An experimental model in the rat

    International Nuclear Information System (INIS)

    Turner, J.H.

    1975-01-01

    A rapid embolic method for consistent induction of stroke in the rat is described. Brain scans were performed using a micro-pinhole collimator system, and the value of the model for studies in localization of radiopharmaceuticals in cerebral ischemia is demonstrated

  9. Sensitivity of Disease Parameters to Flexible Budesonide/Formoterol Treatment in an Allergic Rat Model

    OpenAIRE

    Brange , Charlotte; Smailagic , Amir; Jansson , Anne-Helene; Middleton , Brian; Miller-Larsson , Anna; Taylor , John D.; Silberstein , David S.; Lal , Harbans

    2009-01-01

    Sensitivity of Disease Parameters to Flexible Budesonide/Formoterol Treatment in an Allergic Rat Model correspondance: Corresponding author. Tel.: +46 46 33 6256; fax: +46 46 33 6624. (Brange, Charlotte) (Brange, Charlotte) AstraZeneca R&D Lund--> , Lund--> - SWEDEN (Brange, Charlotte) AstraZeneca R&D Lund--> , Lund--> - SWEDEN (Brange, Charlotte) AstraZeneca R&D Lun...

  10. Translational mixed-effects PKPD modelling of recombinant human growth hormone - from hypophysectomized rat to patients

    DEFF Research Database (Denmark)

    Thorsted, Anders; Thygesen, Peter; Agersø, Henrik

    2016-01-01

    was developed from experimental PKPD studies of rhGH and effects of long-term treatment as measured by insulin-like growth factor 1 (IGF-1) and bodyweight gain in rats. Modelled parameter values were scaled to human values using the allometric approach with fixed exponents for PKs and unscaled for PDs...... and validated through simulations relative to patient data. KEY RESULTS: The final model described rhGH PK as a two compartmental model with parallel linear and non-linear elimination terms, parallel first-order absorption with a total s.c. bioavailability of 87% in rats. Induction of IGF-1 was described...... by an indirect response model with stimulation of kin and related to rhGH exposure through an Emax relationship. Increase in bodyweight was directly linked to individual concentrations of IGF-1 by a linear relation. The scaled model provided robust predictions of human systemic PK of rhGH, but exposure following...

  11. An electron microscopic study on the effects of irradiation on the acinar cells of rat parotid gland

    International Nuclear Information System (INIS)

    Ko, Kwang Jun; Lee, Sang Rae

    1988-01-01

    The author studies the histopathologic changes according to a single or a split does and the time after irradiation on the acinar cells of rat parotid gland. 99 Sprague Dawley rats, weighing about 120 gm, were divided into control and 3 experimental groups. In experimental groups, Group I and II were delivered a single does of 15 Gy, 18 Gy and Group III and IV were delivered two equal split doses of 9 Gy, 10.5 Gy for a 4 hours interval, respectively. The experimental groups were delivered by a cobalt-60 teletherapy unit with a dose rate of 222 cGy/min, source-skin di stance of 50 cm, depth of 1 cm and a field size of 12 X 5 cm. The animals were sacrificed at 1, 2, 3, 6, 12 hours, 1, 3, 7 days after irradiation and examined by light and electro n microscopy. The results were as follows: 1. As the radiation dose increased and acinar cells delivered a single dose exposure were more damaged, and the change of acinar cells appeared faster than those of a split does exposure. 2. The histopathologic change of acinar cells appeared at 1 hour after irradiation. The recovery from damaged acinar cells appeared at 1 day after irradiation and there was a tendency that the recovery from damage of a split dose exposure was somewhat later than of a single dose exposure. 3. Light microscope showed atrophic change of acinar cells and nucleus, degeneration and vesicle formation of cytoplasm, widening of intercellular space and interlobular space. 4. Electron microscope showed loss of nuclear membrane, degeneration of nucleus and nucleoli, clumping of cytoplasm, widening and degeneration of rough endoplasmic reticulum, loss of cristae of mitochondria, lysosome, autophagosome and lipid droplet. 5. Electron microscopically, the change of rough endoplasmic reticulum was most prominent and this appeared at 1 hour after irradiation as early changes of acinar cells. The nuclear change appeared at 2 hours after irradiation and the loss of cristae of mitochondria was observed at 2 hours after

  12. An electron microscopic study on the effects of irradiation on the acinar cells of rat parotid gland

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Kwang Jun; Lee, Sang Rae [Dept. of Oral Radiology, College of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

    1988-11-15

    The author studies the histopathologic changes according to a single or a split does and the time after irradiation on the acinar cells of rat parotid gland. 99 Sprague Dawley rats, weighing about 120 gm, were divided into control and 3 experimental groups. In experimental groups, Group I and II were delivered a single does of 15 Gy, 18 Gy and Group III and IV were delivered two equal split doses of 9 Gy, 10.5 Gy for a 4 hours interval, respectively. The experimental groups were delivered by a cobalt-60 teletherapy unit with a dose rate of 222 cGy/min, source-skin di stance of 50 cm, depth of 1 cm and a field size of 12 X 5 cm. The animals were sacrificed at 1, 2, 3, 6, 12 hours, 1, 3, 7 days after irradiation and examined by light and electro n microscopy. The results were as follows: 1. As the radiation dose increased and acinar cells delivered a single dose exposure were more damaged, and the change of acinar cells appeared faster than those of a split does exposure. 2. The histopathologic change of acinar cells appeared at 1 hour after irradiation. The recovery from damaged acinar cells appeared at 1 day after irradiation and there was a tendency that the recovery from damage of a split dose exposure was somewhat later than of a single dose exposure. 3. Light microscope showed atrophic change of acinar cells and nucleus, degeneration and vesicle formation of cytoplasm, widening of intercellular space and interlobular space. 4. Electron microscope showed loss of nuclear membrane, degeneration of nucleus and nucleoli, clumping of cytoplasm, widening and degeneration of rough endoplasmic reticulum, loss of cristae of mitochondria, lysosome, autophagosome and lipid droplet. 5. Electron microscopically, the change of rough endoplasmic reticulum was most prominent and this appeared at 1 hour after irradiation as early changes of acinar cells. The nuclear change appeared at 2 hours after irradiation and the loss of cristae of mitochondria was observed at 2 hours after

  13. Dipyridamole reduces penile apoptosis in a rat model of post-prostatectomy erectile dysfunction

    Directory of Open Access Journals (Sweden)

    Omer Kutlu

    Full Text Available ABSTRACT Purpose: Despite the nerve-sparing technique, many patients suffer from erectile dysfunction after radical prostatectomy (RP due to cavernous nerve injury. The aim of this study was to evaluate dipyridamole as a potential treatment agent of post-radical prostatectomy erectile dysfunction. Material and methods: A total of 18 male Sprague-Dawley rats were randomized into three experimental Groups (SHAM+DMSO, BCNI+DMSO and BCNI+DIP. An animal model of bilateral cavernous nerve crush injury (BCNI was established to mimic the partial nerve damage during nerve-sparing RP. After creating of BCNI, dimethyl sulphoxide (DMSO was administered transperitoneally as a vehicle to SHAM+DMSO and BCNI+DMSO Groups. BCNI+DIP Group received dipyiridamole (10mg/kg/day as a solution in DMSO for 15 days. Afterwards, rats were evaluated for in vivo erectile response to cavernous nerve stimulation. Penile tissues were also analyzed biochemically for transforming growth factor-β1 (TGF-β1 level. Penile corporal apoptosis was determined by TUNEL method. Results: Erectile response was decreased in rats with BCNI and there was no significant improvement with dipyridamole treatment. TGF-β1 levels were increased in rats with BCNI and decreased with dipyridamole treatment. Dipyridamole led to reduced penile apoptosis in rats with BCNI and there was no significant difference when compared to sham operated rats. Conclusions: Although fifteen-day dipyridamole treatment has failed to improve erectile function in rats with BCNI, the decline in both TGF-β1 levels and apoptotic indices with treatment may be helpful in protecting penile morphology after cavernous nerve injury.

  14. Endothelin B receptors contribute to retinal ganglion cell loss in a rat model of glaucoma.

    Directory of Open Access Journals (Sweden)

    Alena Z Minton

    Full Text Available Glaucoma is an optic neuropathy, commonly associated with elevated intraocular pressure (IOP characterized by optic nerve degeneration, cupping of the optic disc, and loss of retinal ganglion cells which could lead to loss of vision. Endothelin-1 (ET-1 is a 21-amino acid vasoactive peptide that plays a key role in the pathogenesis of glaucoma; however, the receptors mediating these effects have not been defined. In the current study, endothelin B (ET(B receptor expression was assessed in vivo, in the Morrison's ocular hypertension model of glaucoma in rats. Elevation of IOP in Brown Norway rats produced increased expression of ET(B receptors in the retina, mainly in retinal ganglion cells (RGCs, nerve fiber layer (NFL, and also in the inner plexiform layer (IPL and inner nuclear layer (INL. To determine the role of ET(B receptors in neurodegeneration, Wistar-Kyoto wild type (WT and ET(B receptor-deficient (KO rats were subjected to retrograde labeling with Fluoro-Gold (FG, following which IOP was elevated in one eye while the contralateral eye served as control. IOP elevation for 4 weeks in WT rats caused an appreciable loss of RGCs, which was significantly attenuated in KO rats. In addition, degenerative changes in the optic nerve were greatly reduced in KO rats compared to those in WT rats. Taken together, elevated intraocular pressure mediated increase in ET(B receptor expression and its activation may contribute to a decrease in RGC survival as seen in glaucoma. These findings raise the possibility of using endothelin receptor antagonists as neuroprotective agents for the treatment of glaucoma.

  15. Type 2 Diabetes and Metformin Influence on Fracture Healing in an Experimental Rat Model.

    Science.gov (United States)

    La Fontaine, Javier; Chen, Chris; Hunt, Nathan; Jude, Edward; Lavery, Lawrence

    2016-01-01

    Persons with diabetes have a greater incidence of fractures compared with persons without diabetes. However, very little published information is available concerning the deleterious effect of late-stage diabetes on osseous structure and bone healing. The purpose of the present study was to evaluate the role of diabetes on fracture healing in a rat femur repair model. Thirty-six lean and diabetic Zucker rats were subdivided into 3 groups: (1) 12 lean rats as the control group; (2) 12 diabetic rats without blood glucose control (DM group); and (3) 12 diabetic rats treated with 300 mg/kg metformin to reduce the blood glucose levels (DM + Met group). Radiographs were taken every week to determine the incidence of bone repair and delayed union. All the rats were killed at 6 weeks after surgery. In both the sham-operated and the fractured and repaired femurs, significant decreases in the fracture-load/weight and marginal decreases in the fracture-load between the lean and DM groups were found. Metformin treatment significantly reduced the blood glucose and body weight 12 days postoperatively. Furthermore, a decrease in the fracture-load and fracture-load/weight in the repaired femurs was found in the DM + Met group. Diabetes impairs bone fracture healing. Metformin treatment reduces the blood glucose and body weight but had an adverse effect on fracture repair in diabetic rats. Further investigations are needed to reveal the mechanisms responsible for the effects of type 2 diabetes mellitus on bone and bone quality and the effect of medications such as metformin might have in diabetic bone in the presence of neuropathy and vascular disease. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Intermittent Fasting Pretreatment Prevents Cognitive Impairment in a Rat Model of Chronic Cerebral Hypoperfusion.

    Science.gov (United States)

    Hu, Yuan; Yang, Ying; Zhang, Miao; Deng, Min; Zhang, Jun-Jian

    2017-07-01

    Background: Whether intermittent fasting (IF) pretreatment can prevent vascular cognitive dysfunction remains unknown to our knowledge. Objective: We investigated the effects and underlying mechanisms of IF pretreatment on cognitive dysfunction in a permanent 2-vessel occlusion (2VO) vascular dementia rat model. Methods: Male Wistar rats weighing 200 g were subjected to either IF or ad libitum feeding for 12 wk before 2VO surgery. Rats in the IF protocol underwent alternative-day feed deprivation (FD). Memory of the animals was assessed by using the Morris water maze (MWM) and the novel object recognition (NOR) test 6 wk after the surgery. After behavioral testing, malondialdehyde and glutathione concentrations, superoxide dismutase (SOD) activity, gene expression of antioxidative enzymes, inflammatory protein concentrations, and microglia density were determined in the hippocampus of rats. Results: 2-vessel occlusion operation ad libitum (2VO-AL) rats had significantly longer escape latencies on day 4 of the training phase and spent a lower percentage of time in the target quadrant (25% compared with 38% and 41%) in the MWM, and had lower discrimination ratios (47% compared with 65% and 67%) in the NOR test than 2-vessel operation and alternate-day feed deprivation (2VO-FD) and sham operation ad libitum (Sham-AL) rats, respectively ( P < 0.05). This indicates that IF helps to prevent vascular cognitive deficits. 2VO-AL rats also had higher malondialdehyde (3.54 compared with 2.15 and 1.66 nmol/mg protein) and lower glutathione concentrations (53.25 compared with 66.41 and 91.71 nmol/mg protein), lower SOD activity (100.1 compared with 133.3 and 138.5 U/mg protein), lower gene expression of antioxidative enzymes, higher expression of inflammatory proteins, and higher microglia density in the hippocampus than 2VO-FD and Sham-AL rats, respectively ( P < 0.05). This suggests that IF has antioxidative and anti-inflammatory effects. Conclusions: IF pretreatment provided