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Sample records for model rats electronic

  1. Validating myelin water imaging with transmission electron microscopy in a rat spinal cord injury model.

    Science.gov (United States)

    Chen, Henry Szu-Meng; Holmes, Nathan; Liu, Jie; Tetzlaff, Wolfram; Kozlowski, Piotr

    2017-06-01

    Myelin content is an important marker for neuropathology and MRI generated myelin water fraction (MWF) has been shown to correlate well with myelin content. However, because MWF is based on the amount of signal from myelin water, that is, the water trapped between the myelin lipid bilayers, the reading may depend heavily on myelin morphology. This is of special concern when there is a mix of intact myelin and myelin debris, as in the case of injury. To investigate what MWF measures in the presence of debris, we compared MWF to transmission electron microscopy (TEM) derived myelin fraction that measures the amount of compact appearing myelin. A rat spinal cord injury model was used with time points at normal (normal myelin), 3 weeks post-injury (myelin debris), and 8 weeks post-injury (myelin debris, partially cleared). The myelin period between normal and 3 or 8 weeks post-injury cords did not differ significantly, suggesting that as long as the bilayer structure is intact, myelin debris has the same water content as intact myelin. The MWF also correlated strongly with the TEM-derived myelin fraction, suggesting that MWF measures the amount of compact appearing myelin in both intact myelin and myelin debris. From the TEM images, it appears that as myelin degenerates, it tends to form large watery spaces within the myelin sheaths that are not classified as myelin water. The results presented in this study improve our understanding and allows for better interpretation of MWF in the presence of myelin debris. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Neural differentiation of transplanted neural stem cells in a rat model of striatal lacunar infarction: light and electron microscopic observations

    Science.gov (United States)

    Muñetón-Gómez, Vilma C.; Doncel-Pérez, Ernesto; Fernandez, Ana P.; Serrano, Julia; Pozo-Rodrigálvarez, Andrea; Vellosillo-Huerta, Lara; Taylor, Julian S.; Cardona-Gómez, Gloria P.; Nieto-Sampedro, Manuel; Martínez-Murillo, Ricardo

    2012-01-01

    The increased risk and prevalence of lacunar stroke and Parkinson's disease (PD) makes the search for better experimental models an important requirement for translational research. In this study we assess ischemic damage of the nigrostriatal pathway in a model of lacunar stroke evoked by damaging the perforating arteries in the territory of the substantia nigra (SN) of the rat after stereotaxic administration of endothelin-1 (ET-1), a potent vasoconstrictor peptide. We hypothesized that transplantation of neural stem cells (NSCs) with the capacity of differentiating into diverse cell types such as neurons and glia, but with limited proliferation potential, would constitute an alternative and/or adjuvant therapy for lacunar stroke. These cells showed neuritogenic activity in vitro and a high potential for neural differentiation. Light and electron microscopy immunocytochemistry was used to characterize GFP-positive neurons derived from the transplants. 48 h after ET-1 injection, we characterized an area of selective degeneration of dopaminergic neurons within the nigrostriatal pathway characterized with tissue necrosis and glial scar formation, with subsequent behavioral signs of Parkinsonism. Light microscopy showed that grafted cells within the striatal infarction zone differentiated with a high yield into mature glial cells (GFAP-positive) and neuron types present in the normal striatum. Electron microscopy revealed that NSCs-derived neurons integrated into the host circuitry establishing synaptic contacts, mostly of the asymmetric type. Astrocytes were closely associated with normal small-sized blood vessels in the area of infarct, suggesting a possible role in the regulation of the blood brain barrier and angiogenesis. Our results encourage the use of NSCs as a cell-replacement therapy for the treatment of human vascular Parkinsonism. PMID:22876219

  3. 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.

  4. Stationary Electron Atomic Model

    Science.gov (United States)

    Pressler, David E.

    1998-04-01

    I will present a novel theory concerning the position and nature of the electron inside the atom. This new concept is consistant with present experimental evidence and adheres strictly to the valence-shell electron-pair repulsion (VSEPR) model presently used in chemistry for predicting the shapes of molecules and ions. In addition, I will discuss the atomic model concept as being a true harmonic oscillator, periodic motion at resonant frequency which produces radiation at discrete frequencies or line spectra is possible because the electron is under the action of two restoring forces, electrostatic attraction and superconducting respulsion of the electron's magnetic field by the nucleus.

  5. Rat Genome and Model Resources.

    Science.gov (United States)

    Shimoyama, Mary; Smith, Jennifer R; Bryda, Elizabeth; Kuramoto, Takashi; Saba, Laura; Dwinell, Melinda

    2017-07-01

    Rats remain a major model for studying disease mechanisms and discovery, validation, and testing of new compounds to improve human health. The rat's value continues to grow as indicated by the more than 1.4 million publications (second to human) at PubMed documenting important discoveries using this model. Advanced sequencing technologies, genome modification techniques, and the development of embryonic stem cell protocols ensure the rat remains an important mammalian model for disease studies. The 2004 release of the reference genome has been followed by the production of complete genomes for more than two dozen individual strains utilizing NextGen sequencing technologies; their analyses have identified over 80 million variants. This explosion in genomic data has been accompanied by the ability to selectively edit the rat genome, leading to hundreds of new strains through multiple technologies. A number of resources have been developed to provide investigators with access to precision rat models, comprehensive datasets, and sophisticated software tools necessary for their research. Those profiled here include the Rat Genome Database, PhenoGen, Gene Editing Rat Resource Center, Rat Resource and Research Center, and the National BioResource Project for the Rat in Japan. © The Author 2017. Published by Oxford University Press.

  6. Botulinum neurotoxin effects on masseter muscle fibre in WNIN obese rats-Scanning electron microscope analysis.

    Science.gov (United States)

    Nemani, Shivaram; Putchha, Uday K; Periketi, Madhusudhanachary; Pothana, Sailaja; Nappanveettil, Giridharan; Nemani, Harishankar

    2016-09-01

    WNIN/Ob obese mutant rats are unique in comparison to similar rodent models of obesity established in the West. The present study is aimed to evaluate the masticatory function and histological changes in masseter muscle fibres treated with botulinum toxin type A (BoNT/A) in WNIN/Ob rats. Twelve WNIN/Ob obese rats and 12 lean rats at 35 days of age were taken and divided into four groups (6 rats in each group): Group-I (WNIN/Ob) and Group-II (lean) rats were injected with BoNT/A (1 unit) into right side of masseter muscle. For control left masseter of both phenotypes was injected with saline. Group-III (WNIN/Ob) and Group-IV (lean) rats were without any treatment. Growth and food intake was monitored daily for 45 days. Rats were euthanized and gross necropsy was carried out to check any abnormalities. Masseter muscles were dissected and mean muscle mass was recorded. Small portion of muscle was stored in 10% formalin for hematoxylin-eosin (H&E) staining and remaining tissue stored in gluteraldehyde for scanning electron microscopy (SEM). There is a significant decrease in the body weights and food intake of BoNT/A treated obese rats. The H&E staining of the masseter muscle in both groups showed normal morphology and orientation. The SEM analysis showed that, fibre size in BoNT/A treated masseter muscle of obese rats increased more than the saline treated side and in control rats. The increase in the muscle fibre size and transition of muscle fibre subtypes may be due to the reduced masticatory function of the masseter muscle. SCANNING 38:396-402, 2016. © 2015 Wiley Periodicals, Inc. © Wiley Periodicals, Inc.

  7. 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

  8. Electron microscopic study of the effects of thallium poisoning on the rat cerebellum.

    Science.gov (United States)

    Hasan, M; Ashraf, I; Bajpai, V K

    1978-01-01

    Rats were given thallium acetate (5 mg elemental thallium/kg body weight) intra-peritoneally daily for 7 days. The brain was fixed by perfusion-fixation and small pieces of the cerebellum were processed for electron microscopy. Variegated mitochondrial profiles, increased incidence of electron--dense bodies and proliferation of Golgi zones were observed in the thallium--poisoned rat cerebellum. Multilamellar cytoplasmic bodies were discernible in the cerebellar cortex of the thallium-treated rats.

  9. A deterministic model of electron transport for electron probe microanalysis

    Science.gov (United States)

    Bünger, J.; Richter, S.; Torrilhon, M.

    2018-01-01

    Within the last decades significant improvements in the spatial resolution of electron probe microanalysis (EPMA) were obtained by instrumental enhancements. In contrast, the quantification procedures essentially remained unchanged. As the classical procedures assume either homogeneity or a multi-layered structure of the material, they limit the spatial resolution of EPMA. The possibilities of improving the spatial resolution through more sophisticated quantification procedures are therefore almost untouched. We investigate a new analytical model (M 1-model) for the quantification procedure based on fast and accurate modelling of electron-X-ray-matter interactions in complex materials using a deterministic approach to solve the electron transport equations. We outline the derivation of the model from the Boltzmann equation for electron transport using the method of moments with a minimum entropy closure and present first numerical results for three different test cases (homogeneous, thin film and interface). Taking Monte Carlo as a reference, the results for the three test cases show that the M 1-model is able to reproduce the electron dynamics in EPMA applications very well. Compared to classical analytical models like XPP and PAP, the M 1-model is more accurate and far more flexible, which indicates the potential of deterministic models of electron transport to further increase the spatial resolution of EPMA.

  10. Modeling of power electronic systems with EMTP

    Science.gov (United States)

    Tam, Kwa-Sur; Dravid, Narayan V.

    1989-01-01

    In view of the potential impact of power electronics on power systems, there is need for a computer modeling/analysis tool to perform simulation studies on power systems with power electronic components as well as to educate engineering students about such systems. The modeling of the major power electronic components of the NASA Space Station Freedom Electric Power System is described along with ElectroMagnetic Transients Program (EMTP) and it is demonstrated that EMTP can serve as a very useful tool for teaching, design, analysis, and research in the area of power systems with power electronic components. EMTP modeling of power electronic circuits is described and simulation results are presented.

  11. A rat model for hepatitis E virus

    Directory of Open Access Journals (Sweden)

    Yannick Debing

    2016-10-01

    Full Text Available Hepatitis E virus (HEV is one of the prime causes of acute viral hepatitis, and chronic hepatitis E is increasingly recognized as an important problem in the transplant setting. Nevertheless, the fundamental understanding of the biology of HEV replication is limited and there are few therapeutic options. The development of such therapies is partially hindered by the lack of a robust and convenient animal model. We propose the infection of athymic nude rats with the rat HEV strain LA-B350 as such a model. A cDNA clone, pLA-B350, was constructed and the infectivity of its capped RNA transcripts was confirmed in vitro and in vivo. Furthermore, a subgenomic replicon, pLA-B350/luc, was constructed and validated for in vitro antiviral studies. Interestingly, rat HEV proved to be less sensitive to the antiviral activity of α-interferon, ribavirin and mycophenolic acid than genotype 3 HEV (a strain that infects humans. As a proof-of-concept, part of the C-terminal polymerase sequence of pLA-B350/luc was swapped with its genotype 3 HEV counterpart: the resulting chimeric replicon replicated with comparable efficiency as the wild-type construct, confirming that LA-B350 strain is amenable to humanization (replacement of certain sequences or motifs by their counterparts from human HEV strains. Finally, ribavirin effectively inhibited LA-B350 replication in athymic nude rats, confirming the suitability of the rat model for antiviral studies.

  12. 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

  13. 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...

  14. Skeletal dosimetry in a voxel-based rat phantom for internal exposures to photons and electrons.

    Science.gov (United States)

    Xie, Tianwu; Han, Dao; Liu, Yang; Sun, Wenjuan; Liu, Qian

    2010-05-01

    The skeleton makes a significant contribution to the whole body absorbed dose evaluation of rats, since the bone marrow and bone surface in the skeleton express high radiosensitivity and are considered to be important dose-limiting tissues. The bone marrow can be categorized as red bone marrow (RBM) and yellow bone marrow (YBM). It is important to investigate the bone marrow in skeletal dosimetry. Cryosectional color images of the skeleton of a 156 g rat were segmented into mineral bone (including cortical bone and trabecular bone), RBM, and YBM. These three tissue types were identified at 40 different bone sites and integrated into a previously developed voxel-based rat computational phantom. Photon and electron skeletal absorbed fractions were then calculated using the MCNPX Monte Carlo code. Absorbed fraction (AF) and specific absorbed fraction (SAF) for mineral bone, RBM, and YBM at the 40 different bone sites were established for monoenergetic photon and electron sources placed in 18 organs and seven bone sites. Discrete photon energy was varied from 0.01 to 5.0 MeV in 21 discrete steps, while 21 discrete electron energies were studied, from 0.1 to 10.0 MeV. The trends and values found were consistent with the results of other researchers [M. G. Stabin, T. E. Peterson, G. E. Holburn, and M. A. Emmons, "Voxel-based mouse and rat models for internal dose calculations," J. Nucl. Med. 47, 655-659 (2006)]. S-factors for the radionuclides 169Er, 143Pr, 89Sr, 32P, and 90Y, located in 18 organs and seven bone sites for the skeleton, were calculated and are provided in detail. For internal dose calculations, the AF data reveal that the mineral bone in the rat skeletal system is responsible for significant attenuation of gamma rays, especially at low energies. The photon SAF curves of RBM show that, for photon energies greater than 0.6 MeV, there is an increase in secondary photons emitted from the mineral bone as photon energy increases. The SAF values calculated in

  15. Skeletal dosimetry in a voxel-based rat phantom for internal exposures to photons and electrons

    Energy Technology Data Exchange (ETDEWEB)

    Xie Tianwu; Han Dao; Liu Yang; Sun Wenjuan; Liu Qian [Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2010-05-15

    Purpose: The skeleton makes a significant contribution to the whole body absorbed dose evaluation of rats, since the bone marrow and bone surface in the skeleton express high radiosensitivity and are considered to be important dose-limiting tissues. The bone marrow can be categorized as red bone marrow (RBM) and yellow bone marrow (YBM). It is important to investigate the bone marrow in skeletal dosimetry. Methods: Cryosectional color images of the skeleton of a 156 g rat were segmented into mineral bone (including cortical bone and trabecular bone), RBM, and YBM. These three tissue types were identified at 40 different bone sites and integrated into a previously developed voxel-based rat computational phantom. Photon and electron skeletal absorbed fractions were then calculated using the MCNPX Monte Carlo code. Results: Absorbed fraction (AF) and specific absorbed fraction (SAF) for mineral bone, RBM, and YBM at the 40 different bone sites were established for monoenergetic photon and electron sources placed in 18 organs and seven bone sites. Discrete photon energy was varied from 0.01 to 5.0 MeV in 21 discrete steps, while 21 discrete electron energies were studied, from 0.1 to 10.0 MeV. The trends and values found were consistent with the results of other researchers [M. G. Stabin, T. E. Peterson, G. E. Holburn, and M. A. Emmons, ''Voxel-based mouse and rat models for internal dose calculations,'' J. Nucl. Med. 47, 655-659 (2006)]. S-factors for the radionuclides {sup 169}Er, {sup 143}Pr, {sup 89}Sr, {sup 32}P, and {sup 90}Y, located in 18 organs and seven bone sites for the skeleton, were calculated and are provided in detail. Conclusions: For internal dose calculations, the AF data reveal that the mineral bone in the rat skeletal system is responsible for significant attenuation of gamma rays, especially at low energies. The photon SAF curves of RBM show that, for photon energies greater than 0.6 MeV, there is an increase in secondary

  16. Boltzmann-Electron Model in Aleph.

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, Thomas Patrick; Hooper, Russell

    2014-11-01

    We apply the Boltzmann-electron model in the electrostatic, particle-in-cell, finite- element code Aleph to a plasma sheath. By assuming a Boltzmann energy distribution for the electrons, the model eliminates the need to resolve the electron plasma fre- quency, and avoids the numerical "grid instability" that can cause unphysical heating of electrons. This allows much larger timesteps to be used than with kinetic electrons. Ions are treated with the standard PIC algorithm. The Boltzmann-electron model re- quires solution of a nonlinear Poisson equation, for which we use an iterative Newton solver (NOX) from the Trilinos Project. Results for the spatial variation of density and voltage in the plasma sheath agree well with an analytic model

  17. 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.

  18. 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.

  19. Rat Model of Parkes Weber Syndrome.

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    Krzysztof Bojakowski

    Full Text Available The Parkes Weber syndrome is a congenital vascular malformation, characterized by varicose veins, arterio-venous fistulas and overgrown limbs. No broadly accepted animal model of Parkes Weber syndrome has been described. We created side-to-side arterio-venous fistula between common femoral vessels with proximal non-absorbable ligature on common femoral vein limiting the enlargement of the vein diameter in Wistar rats. Contralateral limb was sham operated. Invasive blood pressure measurements in both iliac and inferior cava veins were performed in rats 30 days after fistula creation. Tight circumference and femoral bone length were measured. Histopathology and morphology of soleus muscle, extensor digitorum longus muscle, and the common femoral vessel were analyzed. 30 days following arterio-venous fistula creation, a statistically significant elevation of blood pressure in common iliac vein and limb overgrowth was observed. Limb enlargement was caused by muscle overgrowth, varicose veins formation and bone elongation. Arterio-venous fistula with proximal outflow limitation led to significant increase of femoral vein circumference and venous wall thickness. Our study indicates that the described rat model mimics major clinical features characteristic for the human Parkes Weber syndrome: presence of arterio-venous fistula, venous hypertension and dilatation, varicose veins formation, and the limb hypertrophy. We reveal that limb overgrowth is caused by bone elongation, muscle hypertrophy, and venous dilatation. The newly established model will permit detailed studies on the mechanisms underlying the disease and on the efficacy of novel therapeutic strategies for the Parkes Weber syndrome treatment.

  20. Properties of Flicker ERGs in Rat Models with Retinal Degeneration.

    Science.gov (United States)

    An, Jing; Guo, Qun; Li, Li; Zhang, Zuoming

    2012-01-01

    Purpose. To describe the characteristics of rod and cone functions in rat models for congenital stationary night blindness (CSNB) and retinal cone dysfunction (RCD). Methods. Rod and cone function were isolated by recording the rod-/cone-driven flicker and blue light flicker electroretinograms (ERGs). Results. During dark adaptation, the amplitudes of flicker ERGs in CSNB rats were lower than those in control rats; the responses of RCD rats were similar to control rats. During light adaptation, the amplitudes of flicker ERGs in CSNB rats were reduced; whereas the responses of RCD rats were not detected. Blue flicker ERGs were not observed in CSNB rats at lower frequencies. The cone driven critical flicker frequencies (CFFs) in control rats were 62 Hz. The rod driven CFF of RCD rats was 20 Hz; whereas the rod-/cone-driven CFF of CSNB rats both were about 25 Hz. Conclusions. The function of the rod system was damaged completely, the cones were the source of vision in CSNB rats. Rod system function is excellent in RCD rat. The rods of albinism rats are sensitive to frequencies less than 20 Hz; whereas the cones are sensitive to frequencies up to 62 Hz.

  1. 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.

  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. 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.

  4. Multidisciplinary Modelling Tools for Power Electronic Circuits

    DEFF Research Database (Denmark)

    Bahman, Amir Sajjad

    package, e.g. power module, DFR approach meets trade-offs in electrical, thermal and mechanical design of the device. Today, virtual prototyping of power electronic circuits using advanced simulation tools is becoming attractive due to cost/time saving in building potential designs. With simulations......This thesis presents multidisciplinary modelling techniques in a Design For Reliability (DFR) approach for power electronic circuits. With increasing penetration of renewable energy systems, the demand for reliable power conversion systems is becoming critical. Since a large part of electricity...... is processed through power electronics, highly efficient, sustainable, reliable and cost-effective power electronic devices are needed. Reliability of a product is defined as the ability to perform within its predefined functions under given conditions in a specific time. Because power electronic devices...

  5. Electron-Ionic Model of Ball Lightening

    OpenAIRE

    Fedosin, Sergey G.; Kim, Anatolii S.

    2001-01-01

    The model of ball lightning is presented where outside electron envelope is kept by inside volume of positive charges. The moving of electron in outside envelope is a reason of strong magnetic field, which controls the state of hot ionized air inside of ball lightning. The conditions of origins of ball lightning are investigated and the values of parameters for ball lightning of maximum power are calculated.

  6. 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

  7. 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.

  8. 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.

  9. 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...... eminences grown as free-floating roller-tube cultures can be successfully grafted in a rat Huntington model and that a clinical MR scanner offers a useful noninvasive tool for studying striatal graft development....

  10. [MAM-E17 schizophrenia rat model].

    Science.gov (United States)

    Kállai, Veronika; Tóth, Attila; Gálosi, Rita; Szabó, Imre; Petykó, Zoltán; Karádi, Zoltán; Kállai, János; Lénárd, László

    2015-01-01

    Schizophrenia is a serious neuropsychiatric disorder. Several brain structures, neurotransmitter systems, genetic and environmental risk factors are suspected in the background. Because of its complexity the mechanism of the disorder is not known exactly, so the treatment of patients is unsolved. In the research of schizophrenia application of the rodent models is widespread. In this study one of these models based on the effect of methylazoxymethanol- acetate (MAM) is described, which is a neurodevelopmental, validated rat model. This antimitotic agent is able to evoke a number of schizophrenic symptomes temporarily disrupting the prenatal neurogenesis. The model reproduces numerous histological and neurophysiological changes of the human disorder, moreover it also represents several behavioral and cognitive phenomena resembling those in schizophrenia. A salient advantage of the model is the demonstration of the diachronic feature of the disorder, that is, postpubertal appearance of the positive symptoms. This model provides widespread opportunities for manipulations of the symptoms, so that using it in the future investigations can lead to a better understanding of this disorder.

  11. Mathematical model I. Electron and quantum mechanics

    Directory of Open Access Journals (Sweden)

    Nitin Ramchandra Gadre

    2011-03-01

    Full Text Available The basic particle electron obeys various theories like electrodynamics, quantum mechanics and special relativity. Particle under different experimental conditions behaves differently, allowing us to observe different characteristics which become basis for these theories. In this paper, we have made an attempt to suggest a classical picture by studying the requirements of these three modern theories. The basic presumption is: There must be certain structural characteristics in a particle like electron which make it obey postulates of modern theories. As it is ‘difficult’ to find structure of electron experimentally, we make a mathematical attempt. For a classical approach, we require well defined systems and we have studied a system with two charged particles, proton and electron in a hydrogen atom. An attempt has been made to give a model to describe electron as seen by the proton. We then discuss how the model can satisfy the requirements of the three modern theories in a classical manner. The paper discusses basic aspects of relativity and electrodynamics. However the focus of the paper is on quantum mechanics.

  12. Mathematical model I. Electron and quantum mechanics

    Science.gov (United States)

    Gadre, Nitin Ramchandra

    2011-03-01

    The basic particle electron obeys various theories like electrodynamics, quantum mechanics and special relativity. Particle under different experimental conditions behaves differently, allowing us to observe different characteristics which become basis for these theories. In this paper, we have made an attempt to suggest a classical picture by studying the requirements of these three modern theories. The basic presumption is: There must be certain structural characteristics in a particle like electron which make it obey postulates of modern theories. As it is `difficult' to find structure of electron experimentally, we make a mathematical attempt. For a classical approach, we require well defined systems and we have studied a system with two charged particles, proton and electron in a hydrogen atom. An attempt has been made to give a model to describe electron as seen by the proton. We then discuss how the model can satisfy the requirements of the three modern theories in a classical manner. The paper discusses basic aspects of relativity and electrodynamics. However the focus of the paper is on quantum mechanics.

  13. 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.

  14. 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)

  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. 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. Ontological modeling of electronic health information exchange.

    Science.gov (United States)

    McMurray, J; Zhu, L; McKillop, I; Chen, H

    2015-08-01

    Investments of resources to purposively improve the movement of information between health system providers are currently made with imperfect information. No inventories of system-level electronic health information flows currently exist, nor do measures of inter-organizational electronic information exchange. Using Protégé 4, an open-source OWL Web ontology language editor and knowledge-based framework, we formalized a model that decomposes inter-organizational electronic health information flow into derivative concepts such as diversity, breadth, volume, structure, standardization and connectivity. The ontology was populated with data from a regional health system and the flows were measured. Individual instance's properties were inferred from their class associations as determined by their data and object property rules. It was also possible to visualize interoperability activity for regional analysis and planning purposes. A property called Impact was created from the total number of patients or clients that a health entity in the region served in a year, and the total number of health service providers or organizations with whom it exchanged information in support of clinical decision-making, diagnosis or treatment. Identifying providers with a high Impact but low Interoperability score could assist planners and policy-makers to optimize technology investments intended to electronically share patient information across the continuum of care. Finally, we demonstrated how linked ontologies were used to identify logical inconsistencies in self-reported data for the study. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Podocyte Injury and Albuminuria in Experimental Hyperuricemic Model Rats

    Directory of Open Access Journals (Sweden)

    Shinichiro Asakawa

    2017-01-01

    Full Text Available Although hyperuricemia is shown to accelerate chronic kidney disease, the mechanisms remain unclear. Accumulating studies also indicate that uric acid has both pro- and antioxidant properties. We postulated that hyperuricemia impairs the function of glomerular podocytes, resulting in albuminuria. Hyperuricemic model was induced by oral administration of 2% oxonic acid, a uricase inhibitor. Oxonic acid caused a twofold increase in serum uric acid levels at 8 weeks when compared to control animals. Hyperuricemia in this model was associated with the increase in blood pressure and the wall-thickening of afferent arterioles as well as arcuate arteries. Notably, hyperuricemic rats showed significant albuminuria, and the podocyte injury marker, desmin, was upregulated in the glomeruli. Conversely, podocin, the key component of podocyte slit diaphragm, was downregulated. Structural analysis using transmission electron microscopy confirmed podocyte injury in this model. We found that urinary 8-hydroxy-2′-deoxyguanosine levels were significantly increased and correlated with albuminuria and podocytopathy. Interestingly, although the superoxide dismutase mimetic, tempol, ameliorated the vascular changes and the hypertension, it failed to reduce albuminuria, suggesting that vascular remodeling and podocyte injury in this model are mediated through different mechanisms. In conclusion, vasculopathy and podocytopathy may distinctly contribute to the kidney injury in a hyperuricemic state.

  19. 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.

  20. 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 ...

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

    African Journals Online (AJOL)

    of endogenous opioids in the apoptosis process in a rat model of cirrhotic cardiomyopathy. Materials and Methods: Cirrhosis was ... Conclusion: Apoptosis occurs during cirrhotic cardiomyopathy and endogenous opioid receptors blockade using naltrexone ..... Further research would define the responsible pathways.

  2. 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

  3. Ovariectomized rats as a model of postmenopausal osteoarthritis

    DEFF Research Database (Denmark)

    Høegh-Andersen, Pernille; Tankó, László B; Andersen, Thomas L

    2004-01-01

    We aimed to assess the effect of ovariectomy on cartilage turnover and degradation, to evaluate whether ovariectomized (OVX) rats could form an experimental model of postmenopausal osteoarthritis. The effect of ovariectomy on cartilage was studied using two cohorts of female Sprague-Dawley rats...... for collagen type II degradation products (CTX-II), and bone resorption was quantified in serum using an assay for bone collagen type I fragments (CTX-I). Surface erosion in the cartilage of the knee was more severe in OVX rats than in sham-operated animals, particularly in the 7-month-old cohort (P = 0...... inhibited the ovariectomy-induced acceleration of cartilage and bone turnover and significantly suppressed cartilage degradation and erosion seen in vehicle-treated OVX rats. The study indicates that estrogen deficiency accelerates cartilage turnover and increases cartilage surface erosion. OVX rats provide...

  4. Modeling ion sensing in molecular electronics

    Science.gov (United States)

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

    2014-02-01

    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 (Ca2+), and hydronium ions (H3O+) 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, C9H7NS2), 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.

  5. 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

  6. Radioautographic measurement of electron-induced epidermal kinetic effects in different aged rats

    International Nuclear Information System (INIS)

    Sargent, E.V.; Burns, F.J.

    1987-01-01

    We have previously shown that the ability of rat epidermal cells to repair electron-induced DNA damage decreases as a function of age. The present investigation was performed to examine the relationship between this finding and sensitivity of epidermal cells to the cytotoxic effects of the radiation. Male CD rats at ages 2, 28, 100, 200, 420, and 728 days were injected with [ 3 H]-thymidine [( 3 H]Thd) at a dose of 2 mu Ci/g body weight. One hour later, the rats were anesthetized and the dorsal skin irradiated with various doses of 0.8 meV electrons at a dose rate of 660 rads/min. At 24 h after irradiation, radioautographs were made of a sheet of epidermis that was separated by trypsinization from the underlying dermis. Labeled cells were scored either as singlets or doublets (adjacent labeled cells). The percent labeled cells and percent labeled cells as doublets were determined. The estimated labeling index (the proportion of cells labeled by a single exposure to [ 3 H]Thd) of the epidermal basal layer decreased as a function of age. The slope of the semilog plot of the percent labeled cells as doublets as a function of electron dose indicates that the Do value decreases with increasing age. The results show, however, that the greatest difference in sensitivity occurs between 2-day (neonatal) and 28-day (pubescent) animals and again between 420-day (adult) and 728-day (senescent) animals

  7. The carbohydrate sensitive rat as a model of obesity.

    Directory of Open Access Journals (Sweden)

    Nachiket A Nadkarni

    Full Text Available BACKGROUND: Sensitivity to obesity is highly variable in humans, and rats fed a high fat diet (HFD are used as a model of this inhomogeneity. Energy expenditure components (basal metabolism, thermic effect of feeding, activity and variations in substrate partitioning are possible factors underlying the variability. Unfortunately, in rats as in humans, results have often been inconclusive and measurements usually made after obesity onset, obscuring if metabolism was a cause or consequence. Additionally, the role of high carbohydrate diet (HCD has seldom been studied. METHODOLOGY/FINDINGS: Rats (n=24 were fed for 3 weeks on HCD and then 3 weeks on HFD. Body composition was tracked by MRI and compared to energy expenditure components measured prior to obesity. RESULTS: 1 under HFD, as expected, by adiposity rats were variable enough to be separable into relatively fat resistant (FR and sensitive (FS groups, 2 under HCD, and again by adiposity, rats were also variable enough to be separable into carbohydrate resistant (CR and sensitive (CS groups, the normal body weight of CS rats hiding viscerally-biased fat accumulation, 3 HCD adiposity sensitivity was not related to that under HFD, and both HCD and HFD adiposity sensitivities were not related to energy expenditure components (BMR, TEF, activity cost, and 4 only carbohydrate to fat partitioning in response to an HCD test meal was related to HCD-induced adiposity. CONCLUSIONS/SIGNIFICANCE: The rat model of human obesity is based on substantial variance in adiposity gains under HFD (FR/FS model. Here, since we also found this phenomenon under HCD, where it was also linked to an identifiable metabolic difference, we should consider the existence of another model: the carbohydrate resistant (CR or sensitive (CS rat. This new model is potentially complementary to the FR/FS model due to relatively greater visceral fat accumulation on a low fat high carbohydrate diet.

  8. 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.

  9. Percutaneous Salivary Gland Ablation using Ethanol in a Rat Model

    Directory of Open Access Journals (Sweden)

    Emma Burch

    2017-12-01

    Full Text Available Objectives: Sialorrhea is a common health and psychosocial problem for children with neuromuscular dysfunction secondary to a variety of disorders such as cerebral palsy. Current accepted treatments include the injection of botulinum toxin into the submandibular glands for temporary symptom relief. The purpose of this study is to demonstrate the feasibility of percutaneous ethanol injection for longer lasting salivary gland ablation in an animal model. Material and Methods: Twenty rats were used in this study. In each rat, 98% ethanol was injected into the right submandibular gland under ultrasound guidance. No intervention was performed on the left gland, which served as the control. Ten rats were sacrificed and glands evaluated at three weeks, with the remaining 10 rats sacrificed and evaluated at three months. Unpaired, 1-tailed T-tests were used to analyse the data. Results: Ethanol injections induced a significant and sustained reduction in salivary gland size. Treated glands were 41% smaller by mass than untreated controls in the 10 rats sacrificed at three weeks (P < 0.001. Treated glands were 43% smaller by mass than untreated controls in the 10 rats sacrificed at three months (P < 0.001. Qualitative histologic analysis demonstrated extensive parenchymal damage, inflammation, and fibrosis at both three week and three month time points. Conclusions: Using a rat model, we demonstrated dramatic and sustained submandibular gland damage after percutaneous injection of ethanol.

  10. Alteration of parafollicular (C cells activity in the experimental model of hypothyroidism in rats.

    Directory of Open Access Journals (Sweden)

    Zbigniew Puchalski

    2007-06-01

    Full Text Available Our previous study has shown the alteration of C cells activity in rats with experimental model of hyperthyroidism. The aim of the present study was the evaluation of parafollicular cells activity in rats with hypothyroidism evoked by propylthiouracil (PTU given in drinking water over 21 days. Histological, ultrastructural and immunocytochemical studies using specific antibodies against calcitonin and CGRP were performed on thyroid glands taken from experimental and control groups of rats. Moreover, in all animals the calcitonin plasma levels were evaluated by radioimmunoassay. After chronic administration of PTU, thyroid image showed predominant microfollicular hyperplasia and attenuated density of parafollicular cells. The intensity of immunocytochemical reactions for CT and CGRP were weaker in the majority of C cells in comparison to the control rats, in which strong immunocytochemical reaction was observed. Examination in the electron microscope reveals the features of hypoactivity both in follicular and parafollicular cells, in which the quantity and electron density of secretory granules were smaller in comparison to the control group. These microscopic changes were accompanied by a significant decrease of calcitonin plasma concentration. Alteration of C cells activity in the experimental model of hypothyroidism, accompanied by microfollicular hypertrophy, may point to the mutual cooperation between parafollicular and follicular cells.

  11. A rat model of early stage osteonecrosis induced by glucocorticoids

    Directory of Open Access Journals (Sweden)

    Kerachian Mohammad

    2011-12-01

    Full Text Available Abstract Background Glucocorticoid (GC-induced osteonecrosis (ON is an important complication of medical therapy. The exact pathomechanisms of ON has not been clearly elucidated. There is a need for a reproducible animal model that better approximates the clinical scenario. Methods To determine the genetic susceptibility of rats to develop GC-induced femoral head ON, we evaluated 5 different inbred strains of rats (Spontaneous Hypertensive Rat, Wistar Kyoto, Wistar Furth, SASCO Fisher and Lewis. Prednisone pellets (dosage of 1.82-2.56 mg/kg/day were implanted subcutaneously for 90. After 90 days, the femurs were resected and examined histologically and radiographically. Pathological and histological examination was performed. Hematoxylin and eosin (H & E staining was used to delineate the femoral head osteonecrosis lesions as well as abnormalities of articular cartilage and growth plate. Results The greatest differences in H & E staining were seen in the Wistar Kyoto and Wistar Furth groups. In these groups 4 out of 5 and 3 out of 5, respectively, steroid-induced rats revealed growth plate disruption with acellular areas. The TUNEL apoptosis staining assay for apoptosis revealed that 4 out of 5 of Wistar Kyoto rats, 5 out of 5 of Wistar Furth, 2 out of 4 of surviving Lewis and 2 out of 2 of the surviving spontaneous hypertensive rats had apoptotic osteocytes in trabeculae, whereas none of the Fisher rats showed apoptotic osteocytes. Conclusions We postulate that Wistar Kyoto, Wistar Furth and spontaneous hypertensive rats may be strains of rats more susceptible to develop ON of the femoral head while Fisher rats were the most resistant.

  12. Phenotypic modulation of corpus cavernosum smooth muscle cells in a rat model of cavernous neurectomy.

    Directory of Open Access Journals (Sweden)

    Fan Yang

    Full Text Available Patients undergoing radical prostatectomy (RP are at high risk for erectile dysfunction (ED due to potential cavernous nerve (CN damage during surgery. Penile hypoxia after RP is thought to significantly contribute to ED pathogenesis.We previously showed that corpora cavernosum smooth muscle cells (CCSMCs undergo phenotypic modulation under hypoxic conditions in vitro. Here, we studied such changes in an in vivo post-RP ED model by investigating CCSMCs in bilateral cavernous neurectomy (BCN rats.Sprague-Dawley rats underwent sham (n = 12 or BCN (n = 12 surgery. After 12 weeks, they were injected with apomorphine to determine erectile function. The penile tissues were harvested and assessed for fibrosis using Masson trichrome staining and for molecular markers of phenotypic modulation using immunohistochemistry and western blotting. CCSMC morphological structure was evaluated by hematoxylin-eosin (H&E staining and transmission electron microscopy (TEM.Erectile function was significantly lower in BCN rats than in sham rats. BCN increased hypoxia-inducible factor-1α and collagen protein expression in corpora cavernous tissue. H&E staining and TEM showed that CCSMCs in BCN rats underwent hypertrophy and showed rough endoplasmic reticulum formation. The expression of CCSMC phenotypic markers, such as smooth muscle α-actin, smooth muscle myosin heavy chain, and desmin, was markedly lower, whereas vimentin protein expression was significantly higher in BCN rats than in control rats.CCSMCs undergo phenotype modulation in rats with cavernous neurectomy. The results have unveiled physiological transformations that occur at the cellular and molecular levels and have helped characterize CN injury-induced ED.

  13. 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 unilaterally...... group, 4% (P treatment. Compared with rt-PA treatment alone, 0.5 mg/kg PENTA...... alone or combined with rt-PA did not significantly increase mortality or tendency for hemorrhage....

  14. 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.

  15. 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...

  16. Zinc deficiency in the 11 day rat embryo: a scanning and transmission electron microscope study

    Energy Technology Data Exchange (ETDEWEB)

    Harding, A.J.; Dreosti, I.E.; Tulsi, R.S.

    1988-01-01

    Zinc deficient rat embryos were obtained on the 11th day of pregnancy and examined by scanning and transmission electron microscopy. Scanning electron microscopy revealed an increase in the number of deformed embryos, as well as embryonic growth retardation. In addition, the epithelium of zinc deficient embryos displayed a marked increase in surface microvilli, as well as the presence of blebbing. Transmission electron microscopy indicated extensive cell death in the neural epithelium which was apparently more severely damaged by zinc deficiency than were mesenchymal cells. Mitochondrial cristae were affected to a greater degree than any other membrane of the cell and cristael disintegration appeared to represent the principal cellular lesion preceding necrosis of neural cells and neural tube teratology. 29 references, 4 figures, 1 table.

  17. Transgenic Rat Models for Breast Cancer Research

    Science.gov (United States)

    1998-10-01

    mutations in the rat genome is suggested on the heels of the recent abilities to clone animals from somatic cells, as was the case for sheep named...34 Dolly " (32). In this approach one would generate the desired mutations by gene targeting in somatic cells that can be grown in culture. One cell clones

  18. induced cerebral injury in a rat model

    African Journals Online (AJOL)

    SDS-PAGE was used for the separation of proteins, after which samples were transferred to polyvinylidene fluoride (PVDF) membranes. Monoclonal rabbit antibodies against rat LC3 were used to label the tissue proteins, and thereafter, samples were rinsed with phosphate-buffered saline (PBS) solution with the detergent ...

  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. Modeling Electronic Properties of Complex Oxides

    Science.gov (United States)

    Krishnaswamy, Karthik

    Complex oxides are a class of materials that have recently emerged as potential candidates for electronic applications owing to their interesting electronic properties. The goal of this dissertation is to develop a fundamental understanding of these electronic properties using a combination of first-principles approaches based on density functional theory (DFT), and Schrodinger-Poisson (SP) simulation (Abstract shortened by ProQuest.

  1. 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.

  2. On the Computation of Secondary Electron Emission Models

    OpenAIRE

    Clerc, Sebastien; Dennison, JR; Hoffmann, Ryan; Abbott, Jonathon

    2006-01-01

    Secondary electron emission is a critical contributor to the charge particle current balance in spacecraft charging. Spacecraft charging simulation codes use a parameterized expression for the secondary electron (SE) yield delta(Eo) as a function of the incident electron energy Eo. Simple three-step physics models of the electron penetration, transport, and emission from a solid are typically expressed in terms of the incident electron penetration depth at normal incidence R(Eo) and the mean ...

  3. 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.

  4. 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.

  5. 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.

  6. Detection of visual signals by rats: A computational model

    Science.gov (United States)

    We applied a neural network model of classical conditioning proposed by Schmajuk, Lam, and Gray (1996) to visual signal detection and discrimination tasks designed to assess sustained attention in rats (Bushnell, 1999). The model describes the animals’ expectation of receiving fo...

  7. 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)

  8. 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)

  9. 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.

  10. 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...

  11. Urodynamic evaluation and electrical and pharmacologic neurostimulation. The rat model.

    Science.gov (United States)

    Mersdorf, A; Schmidt, R A; Tanagho, E A

    1993-05-01

    We introduce a rat model that allows simultaneous or independent recording of bladder and sphincteric activity. Via a polyethylene tube inserted into the bladder dome, bladder pressure is measured in response to constant intravesical saline perfusion. The electrical activity of the intra-abdominal urethra (a well-defined striated muscular tube which, in the rat, constitutes the external urethral sphincter) is recorded simultaneously with an electromyography needle electrode. Thus, precise statements can be made about detrusor/sphincter interrelationships. Changes in urodynamic parameters with the anesthetics urethane, methoxyflurane (Metofane), and thiobutabarbital sodium (Inactin) were investigated. High-frequency oscillations in intraluminal bladder pressure could be demonstrated during micturition cycles only in rats anesthetized with urethane or Metofane. As this high-frequency activity is generated by the striated muscle of the intra-abdominal urethra, the external sphincter of the rat is the force behind urine expulsion. The anesthetic Inactin combined with a low intravesical perfusion rate attenuated spontaneous bladder and sphincteric activity and abolished micturition cycles. This rat model can provide accurate and reproducible measurements of urodynamic changes in response to electrical stimulation of the pelvic and pudendal nerves and pharmacologic stimulation with neuropeptides at the lumbosacral spinal cord level. We recommend using this model with urethane or Metofane for physiologic studies of micturition and with Inactin for meticulous neuropharmacologic and electrostimulatory evaluation of urodynamic parameters.

  12. Physiologically based pharmacokinetic modeling of deltamethrin: Development of a rat and human diffusion-limited model

    Science.gov (United States)

    Mirfazaelian et al. (2006) developed a physiologically based pharmacokinetic (PBPK) model for the pyrethroid pesticide deltamethrin in the rat. This model describes gastrointestinal tract absorption as a saturable process mediated by phase III efflux transporters which pump delta...

  13. Gait Impairment in a Rat Model of Focal Cerebral Ischemia

    Directory of Open Access Journals (Sweden)

    Saara Parkkinen

    2013-01-01

    Full Text Available The availability of proper tests for gait evaluation following cerebral ischemia in rats has been limited. The automated, quantitative CatWalk system, which was initially designed to measure gait in models of spinal cord injury, neuropathic pain, and peripheral nerve injury, is said to be a useful tool for the study of motor impairment in stroke animals. Here we report our experiences of using CatWalk XT with rats subjected to transient middle cerebral artery occlusion (MCAO, during their six-week followup. Large corticostriatal infarct was confirmed by MRI in all MCAO rats, which was associated with severe sensorimotor impairment. In contrast, the gait impairment was at most mild, which is consistent with seemingly normal locomotion of MCAO rats. Many of the gait parameters were affected by body weight, walking speed, and motivation despite the use of a goal box. In addition, MCAO rats showed bilateral compensation, which was developed to stabilize proper locomotion. All of these interferences may confound the data interpretation. Taken together, the translational applicability of CatWalk XT in evaluating motor impairment and treatment efficacy remains to be limited at least in rats with severe corticostriatal infarct and loss of body weight.

  14. Decreases in 15-lipoxygenase metabolites in Olmsted syndrome model rats.

    Science.gov (United States)

    Wakabayashi, Masato; Yoshioka, Takeshi; Higashino, Kenichi; Numata, Yoshito; Igarashi, Yasuyuki; Kihara, Akio

    2017-03-01

    Olmsted syndrome (OS) is a congenital dermatosis characterized by palmoplantar keratoderma and periorificial keratotic plaque. TRPV3 (transient receptor potential vanilloid subtype 3) encodes a thermosensitive Ca 2+ channel and is the causative gene of OS. However, the molecular mechanism that causes the pathological development of OS is unclear. We aimed to investigate the molecular mechanisms underlying OS pathology from the perspective of lipid metabolism. Comprehensive lipidomics and microarray analyses were conducted on tissue samples from a non-lesional skin area of OS model rats (Ht rats) and from wild type (WT) rats as the control. Infiltration of leukocytes such as eosinophils and neutrophils and an increase in the fibrotic region were detected in the unaffected skin area of Ht rats compared with the WT rats. Among about 600 lipid species examined, the levels of 15-lipoxygenase (LOX) metabolites, the precursors of anti-inflammatory and pro-resolving lipid mediators, and dihydroceramides decreased by ≥16-fold in Ht rats compared with WT rats. Consistent with the decreases in the 15-LOX metabolites, expression levels of the genes that encode the 15-LOXs, Alox15 and Alox15b, were largely reduced. Conversely, increased expression levels were detected of Il36b, Ccl20, Cxcl1, and Cxcl2, which encode cytokines/chemokines, and S100a8 and S100a9, which encode the Ca 2+ binding proteins that are implicated in epidermal proliferation. The pro-inflammatory state in the unaffected skin of Ht rats caused by decreases in 15-LOX metabolites and increases in cytokines/chemokines may contribute to the pathogenesis of OS. Copyright © 2016 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

  15. Cosmic-ray electrons in the closed-galaxy model

    International Nuclear Information System (INIS)

    Badhwar, G.D.; Stephens, S.A.

    1976-01-01

    We have examined the consequences of the ''closed galaxy'' cosmic-ray confinement model of Rasmussen and Peters with regard to the electron component of cosmic rays. It is found that the predictions of this model are inconsistent with the observed intensity and charge composition of electrons. The model is also inconsistent with the galactic radio emission

  16. A novel rat contact lens model for Fusarium keratitis

    Science.gov (United States)

    Abou Shousha, Mohamed; Santos, Andrea Rachelle C.; Oechsler, Rafael A.; Iovieno, Alfonso; Maestre-Mesa, Jorge; Ruggeri, Marco; Echegaray, Jose J.; Dubovy, Sander R.; Perez, Victor L.; Miller, Darlene; Alfonso, Eduardo C.

    2013-01-01

    Purpose The aim of this study was to develop and characterize a new contact lens–associated fungal keratitis rat model and to assess the ability of non-invasive spectral-domain optical coherence tomography (SD-OCT) to detect pathological changes in vivo in fungal keratitis. Methods We used SD-OCT to image and measure the cornea of Sprague Dawley rats. Fusarium infection was initiated in the rat eye by fitting Fusarium solani–soaked contact lenses on the experimental eye, while the control animals received contact lenses soaked in sterile saline. The fungal infection was monitored with periodic slit-lamp examination and in vivo SD-OCT imaging of the rat eye, and confirmed by histology, counting of viable fungi in the infected rat cornea, and PCR with specific primers for Fusarium sp. Results We imaged and measured the rat cornea with SD-OCT. Custom-made contact lenses were developed based on the OCT measurements. Incubation of contact lenses in a F. solani suspension resulted in biofilm formation. We induced contact lens–associated Fusarium keratitis by fitting the rat eyes for 4 h with the Fusarium-contaminated contact lenses. The SD-OCT images of the cornea correlated well with the slit-lamp and histopathological results and clearly defined clinical signs of infection, namely, increased corneal thickening, loss of epithelial continuity, hyper-reflective areas representing infiltrates, and endothelial plaques characteristic of fungal infection. Moreover, in three cases, SD-OCT detected the infection without any clear findings on slit-lamp examination. Infection was confirmed with histological fungal staining, PCR, and microbiological culture positivity. Conclusions We developed a highly reproducible rat contact lens model and successfully induced contact lens–associated Fusarium keratitis in this model. The clinical presentation of contact lens–associated Fusarium keratitis in the rat model is similar to the human condition. SD-OCT is a valuable tool that

  17. Building and Application of Cardiopulmonary Bypass Model in Rats

    Directory of Open Access Journals (Sweden)

    Zhang Kun

    2017-01-01

    Full Text Available To build a cardiopulmonary bypass model in rats, and research the feasibility. Method Cardiopulmonary bypass was built in 10 adult male SD rats of clean grade through intubation in jugular vein, caudal artery, and femoral artery, and bypass was sustained for 60 min at the flow rate of 100ml/(kg•min to monitor heart rate, blood pressure, blood gas, and electrolyte. Result Puncture succeeded in all the 20 rats, and cardiopulmonary bypass was finished under given conditions. Conclusion The model has the following advantages, economical efficiency, simplicity, minimal invasion, cardiopulmonary bypass parameter setting similar to that of clinical trail, high rate of success. Thus, it is reliable for researching pathological and physiological changes after cardiopulmonary bypass and evaluating therapeutic strategy.

  18. 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.)

  19. 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.

  20. 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.

  1. Electron microscope study of thallium-induced alterations in the oligodendrocytes of the rat area postrema.

    Science.gov (United States)

    Hasan, M; Bajpai, V K; Shipstone, A C

    1977-01-01

    Thallotoxicosis following accidental ingestion of thallium in rodenticides and in cases of homicidal and suicidal ingestion are well documented in the literature. The mechanism of action of thallium, in particular the pathogenesis of its neurotoxic manifestations, is not entirely clear. This is the first electron microscopic investigation dealing with the effect of thallium on the oligodendrocytes of the area postrema. The area postrema is devoid of a blood-brain barrier, indicating that the hemoneural transport of thallous ions may be quite substantial in this region. Rats weighing 155-175 g were given intraperitoneal injections of 5 mg/kg thallous acetate for 7 days (35 mg/kg total dose). Following perfusion-fixation, ultrathin sections of area postrema were examined with an electron microscope. The oligodendrocytes exhibited pleomorphic vacuolated dense bodies in their perikaryon. The findings were also suggestive of the fact that either the multiplication of oligodendrocytes or their aggregation to form "giant cell" was operative.

  2. Evaluation of a modified rat model for functional dyspepsia.

    Science.gov (United States)

    Liang, Qiankun; Yan, Yuan; Mao, Lanfang; Du, Xiaojuan; Liang, Jingjing; Liu, Junhong; Wang, Longde; Li, Hongfang

    2018-04-13

    The purpose of this study was to establish a modified rat model with functional dyspepsia (FD) and analyze the changes in gastrointestinal motility and brain-gut peptide levels in serum and brain-gut axis. Male Wistar rats were divided into control group (Con) and FD model group. FD model was established by stimulating semi-starvation rats via tail damping, provocation, and forced exercise fatigue until gastrointestinal motility disorder appeared, and then levels of motilin, leptin, cholecystokinin (CCK), and vasoactive intestinal peptide (VIP) were detected in serum by enzyme linked immunosorbent assay and in duodenum, antrum, and hypothalamus by immunohistochemistry, reverse transcriptase-polymerase chain reaction, and Western blot. The results showed rates of intestinal propulsion and gastric emptying slowed down markedly compared to Con (P < 0.05), the gastrointestinal electric activity attenuated, and migrating motor complex (MMC) interrupted in the model group. The levels of leptin and VIP markedly increased, but motilin decreased as compared to the Con (P < 0.05) in serum and in the above tissues. It is interesting that the level of CCK decreased in the antrum and duodenum but increased in the hypothalamus as compared to Con (P < 0.05). The modified rat model meets the diagnostic criteria of FD and can be used as a method for studying FD in animals.

  3. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. 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

  6. A New Rat Model for Orthotopic Abdominal Wall Allotransplantation

    Directory of Open Access Journals (Sweden)

    William W. Lao, MD

    2014-04-01

    Conclusions: Technical, histological, and immunological aspects of a new rat model are described. These results give clues to what occurs in human abdominal wall transplantation. In addition, Th1, a proinflammatory cell, was found to be a potential biomarker for allograft rejection.

  7. VHDL Model of Electronic-Lock System

    Directory of Open Access Journals (Sweden)

    J. Noga

    2000-04-01

    Full Text Available The paper describes the design of an electronic-lock system which wascompleted as part of the Basic VHDL course in the Department of Controland Measurement Faculty of Electrical Engineering and Informatics,Technical University of Ostrava, Czech Republic in co-operation withthe Department if Electronic Engineering, University of Hull, GreatBritain in the frame of TEMPUS project no. S_JEP/09468-95.

  8. [Biomarker screening of rat pulmonary hypertension model by transcriptome sequencing].

    Science.gov (United States)

    Hu, F; Xie, L; Yu, L; Chen, J; Liu, H M

    2016-04-01

    To screen relative gene and pathway of rat severe pulmonary hypertension by transcriptome sequencing. Pulmonary hypertension animal model of SD rats was established by left lung resection and hypodermic injection of monocrotaline.Monocrotaline was injected subcutaneously one week after left lung resection.Eight rats at 1, 3, 5 weeks after the injection of monocrotaline respectively were named group M1, group M2 and group M3.Eight normal rats were assigned into control group (group C). The right lung tissue was used for transcriptome sequencing to screen the differentially expressed genes.KEGG pathway analysis was performed to screen the pathways with enriched differentially expressed genes. The animal model was established successfully.The pulmonary artery pressure was as follows: group C (28.6±3.0) mmHg(1 mmHg=0.133 kPa), group M1 (38.9±3.3) mmHg, group M2 (50.8±3.9) mmHg, group M3 (51.5±3.5) mmHg.The pressure elevated in group M1 compared with group C (P=0.007). The pressure in M2 and M3 elevated compared with M1(P=0.002 and Ppulmonary hypertension were epithelial specific receptor tyrosine kinase(Tie2) and thrombospondin-1(TSP-1). Tie2 was down-regulated (qpulmonary hypertension and up-regulated (qpulmonary hypertension.TSP-1 was up-regulated (qpulmonary hypertension and down-regulated (qpulmonary hypertension.In the stage of severe pulmonary hypertension, the differentially expressed genes were enriched mainly in the pathways of phosphatidylinostitol 3-kinase, focal adhesion kinase and extracellular matrix receptor interaction. The study provides transcriptome information of rat pulmonary hypertension model and normal rat.Possible mechanisms of pulmonary hypertension are found.These genes and pathways might be new precursor for the diagnosis and treatment of pulmonary hypertension.

  9. Lessons from rat models of hypertension : from Goldblatt to genetic engineering

    NARCIS (Netherlands)

    Pinto, YM; Paul, M; Ganten, D

    Over the past 50 years various animal models of hypertension have been developed, predominantly in the rat. In this review we discuss the use of the rat as a model of hypertension, and evaluate what these models have taught us. Interestingly, the spontaneously hypertensive rat (SHR) is by far the

  10. 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.

  11. 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.

  12. 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

  13. Neuromodulation attenuates bladder hyperactivity in a rat cystitis model.

    Science.gov (United States)

    Su, Xin; Nickles, Angela; Nelson, Dwight E

    2013-12-06

    We investigated the regulation of urinary bladder function by electrical stimulation of the L6 spinal nerve (SN) using cystometry in normal rats and in rats with cystitis induced by intravesical infusion of dilute acetic acid. In anesthetized rats, a cannula was placed into the bladder dome for saline/acetic acid infusion and intravesical pressure monitoring. Threshold pressure (TP), basal pressure (BP) and inter-contraction interval (ICI) were measured from the bladder pressure recording and void volume (VV) was measured by weighing the voided fluid. Comparison of cystometrograms obtained with infusion of saline or acetic acid showed that acetic acid decreases TP, ICI and VV. These excitatory effects, characteristic of acetic acid induced bladder hyperactivity, were significantly reversed by bilateral SN stimulation (P Hz and at motor threshold (0.19 ± 0.01 milliamps) increased ICI (265%) and VV (217%). In rats perfused with acetic acid, the corresponding increases produced by SN stimulation were 350% for ICI and 383% for VV. The percentage increases in the acetic acid-treated group were not significantly higher than those in saline-treated group. Using continuous flow cystyometry, we find that SN stimulation can produce effects on micturition consistent with its effects on isovolumetric model, and consistent with the therapeutic effect observed with InterStim® therapy in overactive bladder patients. Although the effect of SN stimulation was slightly greater in bladder irritated over normal rats, the difference was not statistically significant.

  14. Experimental model of heterotopic ossification in Wistar rats

    Energy Technology Data Exchange (ETDEWEB)

    Zotz, T.G.G. [Escola Politécnica, Programa de Pós-Graduação em Tecnologia em Saúde, Pontifícia Universidade Católica do Paraná, Curitiba, PR (Brazil); Paula, J.B. de [Médico,Doutor em Engenharia Biomédica, Curitiba, PR (Brazil); Moser, A.D.L. [Escola Politécnica, Programa de Pós-Graduação em Tecnologia em Saúde, Pontifícia Universidade Católica do Paraná, Curitiba, PR (Brazil)

    2012-04-05

    Heterotopic ossification (HO) is a metaplastic biological process in which there is newly formed bone in soft tissues adjacent to large joints, resulting in joint mobility deficit. In order to determine which treatment techniques are more appropriate for such condition, experimental models of induced heterotopic bone formation have been proposed using heterologous demineralized bone matrix implants and bone morphogenetic protein and other tissues. The objective of the present experimental study was to identify a reliable protocol to induce HO in Wistar rats, based on autologous bone marrow (BM) implantation, comparing 3 different BM volumes and based on literature evidence of this HO induction model in larger laboratory animals. Twelve male Wistar albino rats weighing 350/390 g were used. The animals were anesthetized for blood sampling before HO induction in order to quantify serum alkaline phosphatase (ALP). HO was induced by BM implantation in both quadriceps muscles of these animals, experimental group (EG). Thirty-five days after the induction, another blood sample was collected for ALP determination. The results showed a weight gain in the EG and no significant difference in ALP levels when comparing the periods before and after induction. Qualitative histological analysis confirmed the occurrence of heterotopic ossification in all 12 EG rats. In conclusion, the HO induction model was effective when 0.35 mL autologous BM was applied to the quadriceps of Wistar rats.

  15. Experimental model of heterotopic ossification in Wistar rats

    International Nuclear Information System (INIS)

    Zotz, T.G.G.; Paula, J.B. de; Moser, A.D.L.

    2012-01-01

    Heterotopic ossification (HO) is a metaplastic biological process in which there is newly formed bone in soft tissues adjacent to large joints, resulting in joint mobility deficit. In order to determine which treatment techniques are more appropriate for such condition, experimental models of induced heterotopic bone formation have been proposed using heterologous demineralized bone matrix implants and bone morphogenetic protein and other tissues. The objective of the present experimental study was to identify a reliable protocol to induce HO in Wistar rats, based on autologous bone marrow (BM) implantation, comparing 3 different BM volumes and based on literature evidence of this HO induction model in larger laboratory animals. Twelve male Wistar albino rats weighing 350/390 g were used. The animals were anesthetized for blood sampling before HO induction in order to quantify serum alkaline phosphatase (ALP). HO was induced by BM implantation in both quadriceps muscles of these animals, experimental group (EG). Thirty-five days after the induction, another blood sample was collected for ALP determination. The results showed a weight gain in the EG and no significant difference in ALP levels when comparing the periods before and after induction. Qualitative histological analysis confirmed the occurrence of heterotopic ossification in all 12 EG rats. In conclusion, the HO induction model was effective when 0.35 mL autologous BM was applied to the quadriceps of Wistar rats

  16. 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

  17. Modeling mini-orange electron spectrometers

    International Nuclear Information System (INIS)

    Canzian da Silva, Nelson; Dietzsch, Olacio

    1994-01-01

    A method for calculating the transmission of mini-orange electron spectrometers is presented. The method makes use of the analytical solution for the magnetic field of a plane magnet in the calculation of the spectrometer spatial field distribution by superimposing the fields of the several magnets that compose the system. Electron trajectories through the spectrometer are integrated numerically in a Monte Carlo calculation and the transmission of the spectrometer as a function of the electron energy is evaluated. A six-magnet mini-orange spectrometer was built and its transmission functions for several distances from source to detector were measured and compared to the calculations. The overall agreement is found to be good. The method is quite general and can be applied to the design of systems composed of plane magnets, predicting their performance before assembling them. ((orig.))

  18. A comparative study of changes of autophagy in rat models of CLP versus LPS induced sepsis.

    Science.gov (United States)

    Zhang, Binglun; Liu, Chunfeng; Yang, Ni; Wang, Xiangdie

    2017-09-01

    In the present study, two different rat models of sepsis, cecal ligation and puncture (CLP), and lipopolysaccharide (LPS), were established. Changes in autophagy in both models were compared using transmission electron microscopy (TEM), immunohistochemistry, western blotting, and quantitative polymerase chain reaction techniques. Consequently, TEM analysis revealed autophagic bodies in the CLP and LPS sepsis models. In addition, autophagy-related protein LC3 A-specific staining was detected in the cytoplasm. However, analysis of protein and gene expression levels revealed a statistically significant increase in autophagic activity 12 and 24 h following induction of the CLP group, and 2 h following induction of the LPS group. Thus, it was concluded that both models of sepsis exhibited increased autophagic activity of the cardiomyocytes over time. The LPS model was superior to the CLP model in perturbation of molecular biological mechanisms, while the latter would be more likely suited for the study of physiological functions.

  19. Effects of aminoguanidine, a potent nitric oxide synthase inhibitor, on myocardial and organ structure in a rat model of hemorrhagic shock

    Directory of Open Access Journals (Sweden)

    Mona M Soliman

    2014-01-01

    Full Text Available Background: Nitric oxide (NO has been shown to increase following hemorrhagic shock (HS. Peroxynitrite is produced by the reaction of NO with reactive oxygen species, leads to nitrosative stress mediated organ injury. We examined the protective effects of a potent inhibitor of NO synthase, aminoguanidine (AG, on myocardial and multiple organ structure in a rat model of HS. Materials and Methods: Male Sprague Dawley rats (300-350 g were assigned to 3 experimental groups (n = 6 per group: (1 Normotensive rats (N, (2 HS rats and (3 HS rats treated with AG (HS-AG. Rats were hemorrhaged over 60 min to reach a mean arterial blood pressure of 40 mmHg. Rats were treated with 1 ml of 60 mg/kg AG intra-arterially after 60 min HS. Resuscitation was performed in vivo by the reinfusion of the shed blood for 30 min to restore normo-tension. Biopsy samples were taken for light and electron microscopy. Results: Histological examination of hemorrhagic shocked untreated rats revealed structural damage. Less histological damage was observed in multiple organs in AG-treated rats. AG-treatment decreased the number of inflammatory cells and mitochondrial swollen in myocardial cells. Conclusion: AG treatment reduced microscopic damage and injury in multiple organs in a HS model in rats.

  20. 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 ...

  1. 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 w...

  2. Neuropathic pain in a Fabry disease rat model.

    Science.gov (United States)

    Miller, James J; Aoki, Kazuhiro; Moehring, Francie; Murphy, Carly A; O'Hara, Crystal L; Tiemeyer, Michael; Stucky, Cheryl L; Dahms, Nancy M

    2018-03-22

    Fabry disease, the most common lysosomal storage disease, affects multiple organs and results in a shortened life span. This disease is caused by a deficiency of the lysosomal enzyme α-galactosidase A, which leads to glycosphingolipid accumulation in many cell types. Neuropathic pain is an early and severely debilitating symptom in patients with Fabry disease, but the cellular and molecular mechanisms that cause the pain are unknown. We generated a rat model of Fabry disease, the first nonmouse model to our knowledge. Fabry rats had substantial serum and tissue accumulation of α-galactosyl glycosphingolipids and had pronounced mechanical pain behavior. Additionally, Fabry rat dorsal root ganglia displayed global N-glycan alterations, sensory neurons were laden with inclusions, and sensory neuron somata exhibited prominent sensitization to mechanical force. We found that the cation channel transient receptor potential ankyrin 1 (TRPA1) is sensitized in Fabry rat sensory neurons and that TRPA1 antagonism reversed the behavioral mechanical sensitization. This study points toward TRPA1 as a potentially novel target to treat the pain experienced by patients with Fabry disease.

  3. 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.

  4. Azithromycin reduces inflammation in a rat model of acute conjunctivitis

    Science.gov (United States)

    Fernandez-Robredo, Patricia; Recalde, Sergio; Moreno-Orduña, Maite; García-García, Laura; Zarranz-Ventura, Javier; García-Layana, Alfredo

    2013-01-01

    Purpose Macrolide antibiotics are known to have various anti-inflammatory effects in addition to their antimicrobial activity, but the mechanisms are still unclear. The effect of azithromycin on inflammatory molecules in the lipopolysaccharide-induced rat conjunctivitis model was investigated. Methods Twenty-four Wistar rats were divided into two groups receiving topical ocular azithromycin (15 mg/g) or vehicle. In total, six doses (25 µl) were administered as one dose twice a day for three days before subconjunctival lipopolysaccharide injection (3 mg/ml). Before the rats were euthanized, mucus secretion, conjunctival and palpebral edema and redness were evaluated. Real-time polymerase chain reaction was used to determine gene expression for interleukin-6, cyclooxygenase-2, tumor necrosis factor-α, matrix metalloproteinase (MMP)-2, and MMP-9. Interleukin-6 was determined with enzyme-linked immunosorbent assay, nuclear factor-kappa B with western blot, and MMP-2 activity with gelatin zymogram. Four eyes per group were processed for histology and subsequent periodic acid-Schiff staining and CD68 for immunofluorescence. The Student t test or the Wilcoxon test for independent samples was applied (SPSS v.15.0). Results Azithromycin-treated animals showed a significant reduction in all clinical signs (pazithromycin group (p=0.063). Mucus secretion by goblet cells and the macrophage count in conjunctival tissue were also decreased in the azithromycin group (pazithromycin administration ameliorates induced inflammation effects in a rat model of acute conjunctivitis. PMID:23378729

  5. 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.

  6. Validation of the rat model of cryptogenic infantile spasms

    Science.gov (United States)

    Chachua, Tamar; Yum, Mi-Sun; Velíšková, Jana; Velíšek, Libor

    2011-01-01

    Purpose To determine whether a new model of cryptogenic infantile spasms consisting of prenatal priming with betamethasone and postnatal trigger of spasms by N-methyl-D-aspartic acid responds to chronic ACTH treatment, and has similar EEG signature, efficacy of treatments, and behavioral impairments as human infantile spasms. Methods Rats prenatally primed with betamethasone on gestational day 15 were used. Spasms were triggered with N-methyl-D-aspartic acid between postnatal days (P) 10-15 in a single session or in multiple sessions in one subject. The expression of spasms was compared to prenatally saline-injected controls. Effects of relevant treatments (ACTH, vigabatrin, methylprednisolone, rapamycin) were determined in betamethasone-primed rats. In the rats after spasms, behavioral evaluation was performed in the open field and and elevated plus maze on P20-22. Key Findings NMDA at P10-15 (the rat “infant” period) triggers the spasms significantly earlier and in greater numbers in the prenatal betamethasone-exposed brain compared to controls. Similar to human condition, the spasms occur in clusters. Repeated trigger of spasms is associated with ictal EEG electrodecrements and interictal large-amplitude waves, a possible rat variant of hypsarrhythmia. Chronic ACTH treatment in a randomized experiment, and chronic pretreatment with methylprednisolone significantly suppress number of spasms similar to human condition. Pretreatment with vigabatrin, but not rapamycin, suppressed the spasms. Significant behavioral changes occurred following multiple bouts of spasms. Significance The model of infantile spasms has remarkable similarities with the human condition in semiology, EEG, pharmacological response, and long-term outcome. Thus, the model can be used for search of novel and more effective treatments for infantile spasms. PMID:21854372

  7. Effect of Hexavalent Chromium on Electron Leakage of Respiratory Chain in Mitochondria Isolated from Rat Liver

    Directory of Open Access Journals (Sweden)

    Ying Xie

    2013-03-01

    Full Text Available Background/Aims: In the present study, we explored reactive axygen species (ROS production in mitochondria, the mechanism of hexavalent chromium (Cr(VI hepatotoxicity, and the role of protection by GSH. Methods: Intact mitochondria were isolated from rat liver tissues and mitochondrial basal respiratory rates of NADH and FADH2 respiratory chains were determined. Mitochondria were treated with Cr(VI, GSH and several complex inhibitors. Mitochondria energized by glutamate/malate were separately or jointly treated with Rotenone (Rot, diphenyleneiodonium (DPI and antimycinA (Ant, while mitochondria energized by succinate were separately or jointly treated with Rot, DPI ‚ thenoyltrifluoroacetone (TTFA and Ant. Results: Cr(VI concentration-dependently induced ROS production in the NADH and FADH2 respiratory chain in liver mitochondria. Basal respiratory rate of the mitochondrial FADH2 respiratory chain was significantly higher than that of NADH respiratory chain. Hepatic mitochondrial electron leakage induced by Cr(VI from NADH respiratory chain were mainly from ubiquinone binding sites of complex I and complex III. Conclusion: Treatment with 50µM Cr(VI enhances forward movement of electrons through FADH2 respiratory chain and leaking through the ubiquinone binding site of complex III. Moreover, the protective effect of GSH on liver mitochondria electron leakage is through removing excess H2O2 and reducing total ROS.

  8. 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.

  9. 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.

  10. Electronic Warfare in Army Models - A Survey.

    Science.gov (United States)

    1980-08-01

    CCM) PROVING GROUND TENIAS SAMJAM EIEM SPREAD SPECTRUM US ARMY ELECTRONIC FOREIGN SCIENCE & OFFICE OF MISSILE WARFARE LAB (EWL) TECHNOLOGY CENTER...IPAR MULTIRADAR SPREAD SPECTRUM ECMFUZ IRSS OTOALOC TAC ZINGERS EIEM ITF PATCOM TAM EOCM SIM FAC MGM-H4D RFSS TENIAS GTSF MG(-H4H ROLJAM ZAP I HMSM MSL...USAFAS TRASANA USAPAS TCF ASD WPAFU TENIAS ______ ___ ECAC _________ WAR EAGLE _________CATRADA WARRANT am________ 3DBDM ZAP 1 ____________ MEW EWL ZAP 2

  11. Reliability Modeling of Critical Electronic Devices.

    Science.gov (United States)

    1983-05-01

    Electronics, Vol. QE-15, No. 1, up January 1979, pp. 11-13. 15. Newman, D.H. and Ritchie, S., Degradation Pnenomena in Gallium Aluminium Arsenide Stripe...8217RESERVOIR COLD CATHODE TRAP FIGURE 7.2-1: HELIUM-CADMIUM LASER TUBE Principle design considerations relating to the lifetime of the device include (Ref 1): o...available in two basic design types. The contact design is either screw machined or stamped and formed. The screw machined contacts are close entry

  12. Mathematical model I. Electron and quantum mechanics

    OpenAIRE

    Nitin Ramchandra Gadre

    2011-01-01

    The basic particle electron obeys various theories like electrodynamics, quantum mechanics and special relativity. Particle under different experimental conditions behaves differently, allowing us to observe different characteristics which become basis for these theories. In this paper, we have made an attempt to suggest a classical picture by studying the requirements of these three modern theories. The basic presumption is: There must be certain structural characteristics in a particle like...

  13. 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.

  14. 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...

  15. 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

  16. 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 ...

  17. Electronic Business Development as a Sustainable Competitive Advantage Model

    Directory of Open Access Journals (Sweden)

    Narimantas Kazimieras Paliulis

    2012-07-01

    Full Text Available The paper examines the practical usefulness of information technologies in business reviewing electronic business concepts provided in science literature and also the newest tendencies of electronic business development. The paper offers a review of various authors works on e-strategies and IT influence on companies’ functionality. An analysis of disadvantages in various electronic business development models is provided. On the basis of analyses done on the theory of electronic business development and on disadvantages of e-business models, the main aspects of e-business development as sustainable competitive advantage are identified. A fully – formed model of electronic business development as sustainable competitive advantage is presented. Conclusions are provided.Article in Lithuanian

  18. [Experimental model of orthotopic uterus transplantation in the laboratory rat].

    Science.gov (United States)

    Ionac, M; Jiga, L; Motoc, A; Lupu, C; Bordoş, D

    2002-01-01

    This study develops and standardizes an experimental model of uterus transplantation in the laboratory rat. Twelve orthotropic uterus transplantation were done. Animals were randomized in three groups. Postoperative survival was 100% and 75% at 72 hours. Recipients were euthanased at 24 hours, 48 hours and 72 hours and the grafts were harvested. Patency of the microsurgical anastomoses was 100% at 24 hours, 63% at 48 hours and 0% at 72 hours. The explanted uterine grafts were fixed in formalize and analyzed under light microscopy. The acute allograft rejection starts during the second day after transplantation. In additional dissection, anatomy of the pelvic region with regard to the topography of the uterus, tube and ovarian vessels was studied. This model of uterus transplantation in rats proposes a standardized tool for further research regarding cellular mechanisms of the acute allograft rejection and, for future, pregnancy of the transplanted uterus.

  19. 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...

  20. A Unified Model of Secondary Electron Cascades in Diamond

    Energy Technology Data Exchange (ETDEWEB)

    Ziaja, B; London, R A; Hajdu, J

    2004-10-13

    In this paper we present a detailed and unified theoretical treatment of secondary electron cascades that follow the absorption of an X-ray photon. 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 0.1-10 keV. The present paper expands our earlier work 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 {le} 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 late time 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.

  1. New two-fluid (localized + band electron) model for manganites

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. New two-fluid (localized + band electron) model for manganites. ( With HR Krishnamurthy,GV Pai,SR Hassan,V Shenoy,. Key ideas: T Gupta ….) Two types of eg electronic states arise in doped manganites (due to strong JT coupling, strong U, filling conditions, …):.

  2. 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…

  3. 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.…

  4. Efficacy of Female Rat Models in Translational Cardiovascular Aging Research

    OpenAIRE

    Rice, K. M.; Fannin, J. C.; Gillette, C.; Blough, E. R.

    2014-01-01

    Cardiovascular disease is the leading cause of death in women in the United States. Aging is a primary risk factor for the development of cardiovascular disease as well as cardiovascular-related morbidity and mortality. Aging is a universal process that all humans undergo; however, research in aging is limited by cost and time constraints. Therefore, most research in aging has been done in primates and rodents; however it is unknown how well the effects of aging in rat models translate into h...

  5. 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.

  6. 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.

  7. 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.

  8. Electronic Modeling and Design for Extreme Temperatures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We are developing CAD tools, models and methodologies for electronics design for circuit operation in extreme environments with focus on very low temperatures...

  9. 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.

  10. A rat model for embolic encephalitis

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Agerholm, Jørgen Steen; Aalbæk, Bent

    2011-01-01

    gain access to the brain by the circulation and, no foreign materials other than bacteria are implated in the brain. This ensures high face-validity and high construct-validity of the model for three reasons: 1) Cerebral infarction by thrombosis or disseminated intravascular coagulation is a key...

  11. A rat model for embolic encephalitis

    DEFF Research Database (Denmark)

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

    2011-01-01

    -brain-barrier. This provides our model with several advantages: minimized surgical intervention, bacteria gain access to the brain by the circulation and, no foreign materials are implated in the brain. We thereby mirror the human scenario in several ways: 1: Cerebral infarction by thrombosis or disseminated intravascular...

  12. Pazopanib-Induced Hepatotoxicity in an Experimental Rat Model.

    Science.gov (United States)

    Cetin, Bulent; Yılmaz, Guldal Esendagli; Armagan, Berkan; Afsar, Baris; Demirci, Umut; Gulbahar, Ozlem; Gumusay, Ozge; Bilgetekin, Irem; Ozet, Ahmet; Uner, Aytug

    2018-01-01

    Pazopanib is an effective treatment for advanced renal cell carcinoma and soft tissue sarcoma. Besides classical adverse events of this drug class, hepatotoxicity has been described as a frequent side effect. The aim of the present study was to evaluate the effect of pazopanib on the liver in an experimental rat model. Sixteen Wistar albino rats were divided into 3 groups: experimental toxicity was induced with pazopanib (10 mg/kg) administered for 28 days (group 2) or 56 days (group 3) orally by gavage. Group 1 (control group) received only distilled water. Rats in groups 2 and 3 were sacrificed after the collection of blood and tissue samples on the 28th and 56th days, respectively. We found significant differences in bilirubin, alkaline phosphatase, lactate dehydrogenase, glucose, triglyceride, very-low-density lipoprotein, and iron values (p 0.050). All rats in the control group had normal histological features; however, none of the rats in groups 2 and 3 showed normal histology. In group 2, we observed mild sinusoidal dilatation, congestion, enlarged Kupffer cells, accumulation of yellow-brown-black pigment in the Kupffer cells and the accumulation of hemosiderin with Prussian blue reaction in the hepatocytes. In group 3, the findings mentioned above were more prominent, and besides these findings focal acinar transformation and macrovesicular steatosis were also observed. In group 3, mild inflammation within the portal areas was observed consisting of lymphocytes, neutrophils, and eosinophils. This study is the first that reports the biochemical and histopathological evaluation of pazopanib-related hepatic toxicity. © 2018 S. Karger AG, Basel.

  13. 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

  14. 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.

  15. Muon-Electron Conversion in a Family Gauge Boson Model

    OpenAIRE

    Koide, Yoshio; Yamanaka, Masato

    2016-01-01

    We study the $\\mu$-$e$ conversion in muonic atoms via an exchange of family gauge boson (FGB) $A_{2}^{\\ 1}$ in a $U(3)$ FGB model. Within the class of FGB model, we consider three types of family-number assignments for quarks. We evaluate the $\\mu$-$e$ conversion rate for various target nuclei, and find that next generation $\\mu$-$e$ conversion search experiments can cover entire energy scale of the model for all of types of the quark family-number assignments. We show that the conversion rat...

  16. 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.......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....

  17. An efficient strategy for establishing a model of sensorineural deafness in rats

    Directory of Open Access Journals (Sweden)

    Long Ma

    2015-01-01

    Full Text Available Ototoxic drugs can be used to produce a loss of cochlear hair cells to create animal models of deafness. However, to the best of our knowledge, there is no report on the establishment of a rat deafness model through the combined application of aminoglycosides and loop diuretics. The aim of this study was to use single or combined administration of furosemide and kanamycin sulfate to establish rat models of deafness. The rats received intravenous injections of different doses of furosemide and/or intramuscular injections of kanamycin sulfate. The auditory brainstem response was measured to determine the hearing threshold after drug application. Immunocytochemistry and confocal microscopy were performed to evaluate inner ear morphology. In the group receiving combined administration of furosemide and kanamycin, the auditory brainstem response threshold showed significant elevation 3 days after administration, higher than that produced by furosemide or kanamycin alone. The hair cells showed varying degrees of injury, from the apical turn to the basal turn of the cochlea and from the outer hair cells to the inner hair cells. The spiral ganglion cells maintained a normal morphology during the first week after the hair cells completely disappeared, and then gradually degenerated. After 2 months, the majority of spiral ganglion cells disappeared, but a few remained. These findings demonstrate that the combined administration of furosemide and kanamycin has a synergistic ototoxic effect, and that these drugs can produce hair cell loss and hearing loss in rats. These findings suggest that even in patients with severe deafness, electronic cochlear implants may partially restore hearing.

  18. Rodent models in neuroscience research: is it a rat race?

    Directory of Open Access Journals (Sweden)

    Bart Ellenbroek

    2016-10-01

    Full Text Available Rodents (especially Mus musculus and Rattus norvegicus have been the most widely used models in biomedical research for many years. A notable shift has taken place over the last two decades, with mice taking a more and more prominent role in biomedical science compared to rats. This shift was primarily instigated by the availability of a much larger genetic toolbox for mice, particularly embryonic-stem-cell-based targeting technology for gene disruption. With the recent emergence of tools for altering the rat genome, notably genome-editing technologies, the technological gap between the two organisms is closing, and it is becoming more important to consider the physiological, anatomical, biochemical and pharmacological differences between rats and mice when choosing the right model system for a specific biological question. The aim of this short review and accompanying poster is to highlight some of the most important differences, and to discuss their impact on studies of human diseases, with a special focus on neuropsychiatric disorders.

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

    DEFF Research Database (Denmark)

    Guzman, R; Meyer, M; Lövblad, K O

    1999-01-01

    , which was found unaltered for the first 21 days posttransplantation, whereas a hypointense graft signal was detected at 99 days posttransplantation. At 2 days posttransplantation, T2-weighted images showed the graft region as a hyperintense area surrounded by a rim of low signal intensity but at later...... 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 ...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...

  20. Efficacy of female rat models in translational cardiovascular aging research.

    Science.gov (United States)

    Rice, K M; Fannin, J C; Gillette, C; Blough, E R

    2014-01-01

    Cardiovascular disease is the leading cause of death in women in the United States. Aging is a primary risk factor for the development of cardiovascular disease as well as cardiovascular-related morbidity and mortality. Aging is a universal process that all humans undergo; however, research in aging is limited by cost and time constraints. Therefore, most research in aging has been done in primates and rodents; however it is unknown how well the effects of aging in rat models translate into humans. To compound the complication of aging gender has also been indicated as a risk factor for various cardiovascular diseases. This review addresses the systemic pathophysiology of the cardiovascular system associated with aging and gender for aging research with regard to the applicability of rat derived data for translational application to human aging.

  1. Bonding and Molecular Geometry without Orbitals- The Electron Domain Model

    Science.gov (United States)

    Gillespie, Ronald J.; Spencer, James N.; Moog, Richard S.

    1996-07-01

    An alternative to the conventional valence bond approach to bonding and geometry-the electron domain model-is presented. This approach avoids some of the problems with the standard approach and presents fewer difficulties for the student, while still providing a physical basis for the VSEPR model and a link to the valence bond model. The electron domain model also emphasizes the importance of the Pauli principle in understanding the chemical bond and molecular geometry. A letter from Derek W. Smith in our April 2000 issue addresses the above.

  2. Rat Models of Ventricular Fibrillation Following Acute Myocardial Infarction

    DEFF Research Database (Denmark)

    Hundahl, Laura A.; Tfelt-Hansen, Jacob; Jespersen, Thomas

    2017-01-01

    A number of animal models have been designed in order to unravel the underlying mechanisms of acute ischemia-induced arrhythmias and to test compounds and interventions for antiarrhythmic therapy. This is important as acute myocardial infarction (AMI) continues to be the major cause of sudden car...... for ventricular arrhythmias occurring during the acute phase of AMI. It provides a description of models developed, advantages and disadvantages of rats, as well as an overview of the most important interventions investigated and the relevance for human pathophysiology....

  3. A rat model with an isolated bladder in situ

    DEFF Research Database (Denmark)

    Thulesen, J; Olsen, P S; Grevstad, J U

    1997-01-01

    to the proximal part of the descending colon. The animals were treated with antibiotics, and saline was infused daily into the bladder in order to prevent atrophy. This in situ model is considered to be useful in studies investigating the influence of specific compounds, such as carcinogens, on the bladder......This paper describes our method for producing a rat model with an isolated bladder in situ in which the bladder makes no contact with urine. First, the right kidney was removed, then an external catheter was placed in the right ureter for bladder infusions, and next the left ureter was anatomosed...

  4. 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

  5. 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.

  6. A model for electron/ion recombination in ionization chambers

    International Nuclear Information System (INIS)

    Sailor, W.C.

    1988-05-01

    The recombination of free electrons and positive ions along charged particle tracks in gases has been modeled using electron tranport equations, which assume homogeneous distribution in the vicinity of the tracks. The equations include space charge terms, which have been negelected in previous models. A formula for the electron yield as a function of detector applied potential is obtained from a perturbation solution valid when the ratio of the Debye length to the charge column radius is larger then unity. When this ratio is very large, the formula reduces to that of previous models. Pulse height measurements in a 3 He ionization chamber indicate 2% to 30% losses to recombination which vary with applied field, particle type, and energy. Using reasonable values for the electron transport coefficients, the calculated loss of signal to recommendation is generally in agreement with experiment, but the variation with applied bias is stronger in the experiment

  7. A rat model for muscle regeneration in the soft palate.

    Directory of Open Access Journals (Sweden)

    Paola L Carvajal Monroy

    Full Text Available 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 (immunohistochemistry (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.

  8. Ischemic postconditioning influences electron transport chain protein turnover in Langendorff-perfused rat hearts

    Directory of Open Access Journals (Sweden)

    Song Cao

    2016-02-01

    Full Text Available Ischemia postconditioning (IPo is a promising strategy in reducing myocardial ischemia reperfusion (I/R injury (MIRI, but its specific molecular mechanism is incompletely understood. Langendorff-perfused isolated rat hearts were subjected to global I/R and received IPo in the absence or presence of the mitochondrial ATP-sensitive potassium channel (mitoKATP blocker 5-hydroxydecanoate (5-HD. Myocardial mitochondria were extracted and mitochondrial comparative proteomics was analyzed. IPo significantly reduces post-ischemic myocardial infarction and improved cardiac function in I/R rat hearts, while 5-HD basically cancelled IPo’s myocardial protective effect. Joint application of two-dimensional polyacrylamide gel electrophoresis (2DE and MALDI-TOF MS identified eight differentially expressed proteins between groups. Expression of cardiac succinate dehydrogenase (ubiquinone flavoprotein subunit (SDHA increased more than two-fold after I/R, while IPo led to overexpression of dihydrolipoyl dehydrogenase (DLD, NADH dehydrogenase (ubiquinone flavoprotein 1 and isoform CRA_b (NDUFV1. When the mitoKATP was blocked, MICOS complex subunit Mic60 (IMMT and Stress-70 protein (Grp75 were over expressed, while DLDH, ATPase subunit A (ATPA and rCG44606 were decreased. Seven of the differential proteins belong to electron transport chain (ETC or metabolism regulating proteins, and five of them were induced by closing mitoKATP in I/R hearts. We thus conclude that IPo’s myocardial protective effect relies on energy homeostasis regulation. DLD, SDHA, NDUFV1, Grp75, ATPA and rCG44606 may contribute to IPo’s cardial protective effect.

  9. Ischemic postconditioning influences electron transport chain protein turnover in Langendorff-perfused rat hearts.

    Science.gov (United States)

    Cao, Song; Liu, Yun; Wang, Haiying; Mao, Xiaowen; Chen, Jincong; Liu, Jiming; Xia, Zhengyuan; Zhang, Lin; Liu, Xingkui; Yu, Tian

    2016-01-01

    Ischemia postconditioning (IPo) is a promising strategy in reducing myocardial ischemia reperfusion (I/R) injury (MIRI), but its specific molecular mechanism is incompletely understood. Langendorff-perfused isolated rat hearts were subjected to global I/R and received IPo in the absence or presence of the mitochondrial ATP-sensitive potassium channel (mitoKATP) blocker 5-hydroxydecanoate (5-HD). Myocardial mitochondria were extracted and mitochondrial comparative proteomics was analyzed. IPo significantly reduces post-ischemic myocardial infarction and improved cardiac function in I/R rat hearts, while 5-HD basically cancelled IPo's myocardial protective effect. Joint application of two-dimensional polyacrylamide gel electrophoresis (2DE) and MALDI-TOF MS identified eight differentially expressed proteins between groups. Expression of cardiac succinate dehydrogenase (ubiquinone) flavoprotein subunit (SDHA) increased more than two-fold after I/R, while IPo led to overexpression of dihydrolipoyl dehydrogenase (DLD), NADH dehydrogenase (ubiquinone) flavoprotein 1 and isoform CRA_b (NDUFV1). When the mitoKATP was blocked, MICOS complex subunit Mic60 (IMMT) and Stress-70 protein (Grp75) were over expressed, while DLDH, ATPase subunit A (ATPA) and rCG44606 were decreased. Seven of the differential proteins belong to electron transport chain (ETC) or metabolism regulating proteins, and five of them were induced by closing mitoKATP in I/R hearts. We thus conclude that IPo's myocardial protective effect relies on energy homeostasis regulation. DLD, SDHA, NDUFV1, Grp75, ATPA and rCG44606 may contribute to IPo's cardial protective effect.

  10. 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 ...... describe myogenic responses and tubuloglomerular feedback responses separately. The method is applied to data from normo- and hypertensive Dahl rats, and a discriminator that separates data from normotensive Dahl R rats and hypertensive Dahl S rats is constructed....

  11. Task Flow Modeling in Electronic Business Environments

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available In recent years, internet based commerce has developed as a new paradigm. Many factors such as "at home delivery", easy ordering, and usually lower prices contributed to the success of the e-commerce. However, more recently, companies realized that one of the major factors in having a successful internet based business is the design of a user interface that is in concordance with the users' expectations, which includes both functionality and user friendly features. The func-tionality feature of an e-business interface is one of the most important elements when discussing about a specific internet based business. In our paper, we present methods to model task flows for e-business interfaces. We strengthen our study with the design modeling of a practical scenario that may appear in an on-line commercial environment.

  12. 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

  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. An animal model of spontaneous metabolic syndrome: Nile grass rat.

    Science.gov (United States)

    Noda, Kousuke; Melhorn, Mark I; Zandi, Souska; Frimmel, Sonja; Tayyari, Faryan; Hisatomi, Toshio; Almulki, Lama; Pronczuk, Andrzej; Hayes, K C; Hafezi-Moghadam, Ali

    2010-07-01

    Metabolic syndrome (MetS) is a prevalent and complex disease, characterized by the variable coexistence of obesity, dyslipidemia, hyperinsulinaemia, and hypertension. The alarming rise in the prevalence of metabolic disorders makes it imperative to innovate preventive or therapeutic measures for MetS and its complications. However, the elucidation of the pathogenesis of MetS has been hampered by the lack of realistic models. For example, the existing animal models of MetS, i.e., genetically engineered rodents, imitate certain aspects of the disease, while lacking other important components. Defining the natural course of MetS in a spontaneous animal model of the disease would be desirable. Here, we introduce the Nile grass rat (NGR), Arvicanthis niloticus, as a novel model of MetS. Studies of over 1100 NGRs in captivity, fed normal chow, revealed that most of these animals spontaneously develop dyslipidemia (P<0.01), and hyperglycemia (P<0.01) by 1 yr of age. Further characterization showed that the diabetic rats develop liver steatosis, abdominal fat accumulation, nephropathy, atrophy of pancreatic islets of Langerhans, fatty streaks in the aorta, and hypertension (P<0.01). Diabetic NGRs in the early phase of the disease develop hyperinsulinemia, and show a strong inverse correlation between plasma adiponectin and HbA1c levels (P<0.01). These data indicate that the NGR is a valuable, spontaneous model for exploring the etiology and pathophysiology of MetS as well as its various complications.

  15. [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.

  16. Classical Antiferromagnetism in Kinetically Frustrated Electronic Models

    Science.gov (United States)

    Sposetti, C. N.; Bravo, B.; Trumper, A. E.; Gazza, C. J.; Manuel, L. O.

    2014-05-01

    We study, by means of the density matrix renormalization group, the infinite U Hubbard model—with one hole doped away from half filling—in triangular and square lattices with frustrated hoppings, which invalidate Nagaoka's theorem. We find that these kinetically frustrated models have antiferromagnetic ground states with classical local magnetization in the thermodynamic limit. We identify the mechanism of this kinetic antiferromagnetism with the release of the kinetic energy frustration, as the hole moves in the established antiferromagnetic background. This release can occur in two different ways: by a nontrivial spin Berry phase acquired by the hole, or by the effective vanishing of the hopping amplitude along the frustrating loops.

  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. 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.

  19. Modeling and simulation of electronic structure, material interface and random doping in nano-electronic devices

    International Nuclear Information System (INIS)

    Chen Duan; Wei Guowei

    2010-01-01

    The miniaturization of nano-scale electronic devices, such as metal oxide semiconductor field effect transistors (MOSFETs), has given rise to a pressing demand in the new theoretical understanding and practical tactic for dealing with quantum mechanical effects in integrated circuits. Modeling and simulation of this class of problems have emerged as an important topic in applied and computational mathematics. This work presents mathematical models and computational algorithms for the simulation of nano-scale MOSFETs. We introduce a unified two-scale energy functional to describe the electrons and the continuum electrostatic potential of the nano-electronic device. This framework enables us to put microscopic and macroscopic descriptions in an equal footing at nano-scale. By optimization of the energy functional, we derive consistently coupled Poisson-Kohn-Sham equations. Additionally, layered structures are crucial to the electrostatic and transport properties of nano-transistors. A material interface model is proposed for more accurate description of the electrostatics governed by the Poisson equation. Finally, a new individual dopant model that utilizes the Dirac delta function is proposed to understand the random doping effect in nano-electronic devices. Two mathematical algorithms, the matched interface and boundary (MIB) method and the Dirichlet-to-Neumann mapping (DNM) technique, are introduced to improve the computational efficiency of nano-device simulations. Electronic structures are computed via subband decomposition and the transport properties, such as the I-V curves and electron density, are evaluated via the non-equilibrium Green's functions (NEGF) formalism. Two distinct device configurations, a double-gate MOSFET and a four-gate MOSFET, are considered in our three-dimensional numerical simulations. For these devices, the current fluctuation and voltage threshold lowering effect induced by the discrete dopant model are explored. Numerical convergence

  20. Theoretical model of fast electron emission from surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Reinhold, C.; Burgdoerfer, J. [Univ. of Tennessee, Knoxville, TN (United States)]|[Oak Ridge National Laboratory, TN (United States)

    1993-05-01

    Electron emission in glancing-angle ion-surface collisions has become a focus of ion-surface interactions. Electron spectra can provide detailed information on the above surface neutralization dynamics of multiply charged ions, the electronic structure of the surface (surface density of states), and the long-ranged image interactions near the surface. Recent experiments have found that the convoy peak, well known from ion-atom and ion-solid collisions, is dramatically altered. The peak is broadened and shifted in energy which has been attributed to dynamical image interactions. We present a microscopic model for the emission of fast electrons in glancing-angle surface collisions. A classical trajectory Monte Carlo approach is utilized to calculate the evolution of electrons in the presence of their self image, the projectile Coulomb field and the image potential induced by the projectile. The excitation of collective surface modes is also incorporated.

  1. 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.

  2. 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.

  3. A New Perspective for Modeling Power Electronics Converters : Complementarity Framework

    NARCIS (Netherlands)

    Vasca, Francesco; Iannelli, Luigi; Camlibel, M. Kanat; Frasca, Roberto

    2009-01-01

    The switching behavior of power converters with "ideal" electronic devices (EDs) makes it difficult to define a switched model that describes the dynamics of the converter in all possible operating conditions, i.e., a "complete" model. Indeed, simplifying assumptions on the sequences of modes are

  4. Test of theoretical models for ultrafast heterogeneous electron ...

    Indian Academy of Sciences (India)

    Administrator

    with the predictions of different theoretical models for light-induced ultrafast heterogeneous electron transfer (HET). ... theory model based on molecular dynamics simulations for the vibrational modes were also considered. Based on the known vibrational .... Pseudo 3D map of a 2PPE measurement with. Pe' achored via the ...

  5. 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

  6. 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

  7. MODEL OF ELECTRON CLOUD INSTABILITY IN FERMILAB RECYCLER

    Energy Technology Data Exchange (ETDEWEB)

    Antipov, Sergey A. [Chicago U.; Burov, A. [Fermilab; Nagaitsev, S. [Fermilab

    2016-10-04

    An electron cloud instability might limit the intensity in the Fermilab Recycler after the PIP-II upgrade. A multibunch instability typically develops in the horizontal plane within a hundred turns and, in certain conditions, leads to beam loss. Recent studies have indicated that the instability is caused by an electron cloud, trapped in the Recycler index dipole magnets. We developed an analytical model of an electron cloud driven instability with the electrons trapped in combined function dipoles. The resulting instability growth rate of about 30 revolutions is consistent with experimental observations and qualitatively agrees with the simulation in the PEI code. The model allows an estimation of the instability rate for the future intensity upgrades.

  8. 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.

  9. Transformer Model in Wide Frequency Bandwidth for Power Electronics Systems

    OpenAIRE

    Gonzalez-Garcia, Carlos; Pleite, Jorge

    2013-01-01

    The development of the smart grids leads to new challenges on the power electronics equipment and power transformers. The use of power electronic transformer presents several advantages, but new problems related with the application of high frequency voltage and current components come across. Thus, an accurate knowledge of the transformer behavior in a wide frequency range is mandatory. A novel modeling procedure to relate the transformer physical behavior and its frequency response by means...

  10. Modeling electron fractionalization with unconventional Fock spaces

    Science.gov (United States)

    Cobanera, Emilio

    2017-08-01

    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 D=1,2,3,\\ldots 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.

  11. Mechanism of auditory hypersensitivity in human autism using autism model rats.

    Science.gov (United States)

    Ida-Eto, Michiru; Hara, Nao; Ohkawara, Takeshi; Narita, Masaaki

    2017-04-01

    Auditory hypersensitivity is one of the major complications in autism spectrum disorder. The aim of this study was to investigate whether the auditory brain center is affected in autism model rats. Autism model rats were prepared by prenatal exposure to thalidomide on embryonic day 9 and 10 in pregnant rats. The superior olivary complex (SOC), a complex of auditory nuclei, was immunostained with anti-calbindin d28k antibody at postnatal day 50. In autism model rats, SOC immunoreactivity was markedly decreased. Strength of immunostaining of SOC auditory fibers was also weak in autism model rats. Surprisingly, the size of the medial nucleus of trapezoid body, a nucleus exerting inhibitory function in SOC, was significantly decreased in autism model rats. Auditory hypersensitivity may be, in part, due to impairment of inhibitory processing by the auditory brain center. © 2016 Japan Pediatric Society.

  12. 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

  13. Three-dimensional structure of peripheral exocrine gland in rat pancreas: reconstruction using transmission electron microscopic examination of serial sections.

    Science.gov (United States)

    Ashizawa, Nobuo; Sakai, Toshio; Yoneyama, Tsunao; Naora, Hiroyuki; Kinoshita, Yoshikazu

    2005-11-01

    The purpose of this study was to elucidate the 3-dimensional structure of the peripheral pancreatic exocrine gland. We observed serial sections of rat pancreatic tissue using a transmission electron microscope and traced the intercalated duct lumina, intra-acinar secretory canaliculi, intercalated duct cells or centroacinar cells, and basement membranes of acini onto a transparent sheet. These traced diagrams were reconstructed. The intra-acinar secretory canaliculus had branches but no anastomosis. The intercellular secretory canaliculus was extended from the central lumen through the space between the lateral surfaces of the acinar cells to the acinar base. Furthermore, the cytoplasmic process of each centroacinar cell was extended along the central lumen and connected to an intercalated duct cell; thus, centroacinar cells with the same structure as intercalated duct cells were not isolated from the intercalated duct cells. In this study, we elucidated the normal 3-dimensional structure of the peripheral pancreatic exocrine gland. To understand the pathogenesis of chronic pancreatitis, in the future we intend to examine the morphologic changes of pancreatic tissue during the onset and advancement of chronic pancreatitis using animal models.

  14. Novel rat tail discitis model using bioluminescent Staphylococcus aureus.

    Science.gov (United States)

    Bostian, Phillip A; Karnes, Jonathan M; Cui, Shari; Robinson, Lisa J; Daffner, Scott D; Witt, Michelle R; Emery, Sanford E

    2017-09-01

    Management of spondylodiscitis is a challenging clinical problem requiring medical and surgical treatment strategies. The purpose of this study was to establish a rat model of spondylodiscitis that utilizes bioluminescent Staphylococcus aureus (S. aureus), thus permitting in vivo surveillance of infection intensity. Inocula of the bioluminescent S. aureus strain XEN36 were created in concentrations of 10 2 CFU/0.1 ml, 10 4  CFU/0.1 ml, and 10 6  CFU/0.1 ml. Three groups of rats were injected with the bacteria in the most proximal intervertebral tail segment. The third most proximal tail segment was injected with saline as a control. Bioluminescence was measured at baseline, 3 days, and weekly for a total of 6 weeks. Detected bioluminescence for each group peaked at day 3 and returned to baseline in 21 days. The average intensity was highest for the experimental group injected with the most concentrated bacterial solution (10 6  CFU/0.1 ml). Radiographic analysis revealed loss of intervertebral disc space and evidence of osseous bridging. Saline-injected spaces exhibited no decrease in intervertebral spacing as compared to distal sites. Histologic analysis revealed neutrophilic infiltrates, destruction of the annulus fibrosus and nucleus pulposus, destruction of vertebral endplates, and osseous bridging. Saline-injected discs exhibited preserved annulus fibrosus and nucleus pulposus on histology. This study demonstrates that injection of bioluminescent S. aureus into the intervertebral disc of a rat tail is a viable animal model for spondylodiscitis research. This model allows for real-time, in vivo quantification of infection intensity, which may decrease the number of animals required for infection studies of the intervertebral disc. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2075-2081, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  15. Ionospheric topside models compared with experimental electron density profiles

    Directory of Open Access Journals (Sweden)

    S. M. Radicella

    2005-06-01

    Full Text Available Recently an increasing number of topside electron density profiles has been made available to the scientific community on the Internet. These data are important for ionospheric modeling purposes, since the experimental information on the electron density above the ionosphere maximum of ionization is very scarce. The present work compares NeQuick and IRI models with the topside electron density profiles available in the databases of the ISIS2, IK19 and Cosmos 1809 satellites. Experimental electron content from the F2 peak up to satellite height and electron densities at fixed heights above the peak have been compared under a wide range of different conditions. The analysis performed points out the behavior of the models and the improvements needed to be assessed to have a better reproduction of the experimental results. NeQuick topside is a modified Epstein layer, with thickness parameter determined by an empirical relation. It appears that its performance is strongly affected by this parameter, indicating the need for improvements of its formulation. IRI topside is based on Booker's approach to consider two parts with constant height gradients. It appears that this formulation leads to an overestimation of the electron density in the upper part of the profiles, and overestimation of TEC.

  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. 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

  18. Fluorescing fatty acids in rat fatty liver models.

    Science.gov (United States)

    Croce, Anna C; Ferrigno, Andrea; Di Pasqua, Laura G; Berardo, Clarissa; Mannucci, Barbara; Bottiroli, Giovanni; Vairetti, Mariapia

    2017-06-01

    The autofluorescence (AF) of NAD(P)H and flavins has been at the basis of many in-situ studies of liver energy metabolism and functionality. Conversely, few data have been so far reported on fluorescing lipids. In this work we investigated the AF of liver lipid extracts from two fatty liver models, Wistar rats fed with MCD diet for 12 days (Wi-MCD), and obese (fa/fa) Zucker rats. Among the most abundant fatty acids in the lipid extracts, indicated by mass spectrometry, arachidonic acid (AA) exhibited higher quantum yield than the other fluorescing fatty acids (FLFA), and red shifted AF spectrum. This allowed to estimate the AA contribution to the overall emission of lipid extracts by curve fitting analysis. AA prevailed in obese Zucker livers, accounting for the different AF spectral profiles between the two models. AF and mass spectrometry indicated also a different balance between the fluorescing fraction and the overall amount of AA in the two models. The ability of AF to detect directly AA and FLFA was demonstrated, suggesting its supportive role as tool in wide-ranging applications, from the control of animal origin food, to experimental investigations on liver fat accumulation, lipotoxicity and disease progression, with potential translation to the clinics. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. The MAM-E17 schizophrenia rat model: Comprehensive behavioral analysis of pre-pubertal, pubertal and adult rats.

    Science.gov (United States)

    Kállai, Veronika; Tóth, Attila; Gálosi, Rita; Péczely, László; Ollmann, Tamás; Petykó, Zoltán; László, Kristóf; Kállai, János; Szabó, Imre; Karádi, Zoltán; Lénárd, László

    2017-08-14

    The MAM-E17 model is one of the most accepted schizophrenia rat models, which follows the neurodevelopmental theory of the disease. While symptoms of MAM-E17 rats were studied extensively, their examinations were usually restricted to adulthood and in a few cases to prepuberty. It is well known, however, that schizophrenia symptoms often start at puberty or early adulthood. Therefore the purpose of this study was to investigate the behavioral characteristics of MAM-E17 rats in various tests throughout three different age-periods, namely in prepuberty, late puberty and adulthood. In open field test, MAM-E17 rats displayed increased locomotor activity, elevated sniffing frequency and, as tendency, enhanced rearing activity. The elevated activity turned up in late puberty and remained there in adulthood, too. There was also a deficient prepulse inhibition (PPI) of startle response in late puberty and adulthood, but not before puberty. In rotarod task, MAM-treated rats performed better than control rats. The enhanced performance on rotarod was only present in late puberty and adulthood. In elevated plus maze test MAM-treated rats displayed diminished anxiety mostly in prepuberty. Histological analysis revealed reduced volume and cell disarray in the dorsal hippocampus. This is the first comprehensive study about symptoms of MAM-E17 rats manifested in behavioral tests carried out in prepuberty, late puberty and adulthood. Results display the age-dependent appearance of schizophrenia symptoms in the same rats. The present findings provide basic information to accomplish the schizophrenia related animal research, as well as can also confer further data to develop preventive treatment for human patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. [Causes of death in STZ-induced rat models of diabetes mellitus].

    Science.gov (United States)

    Wang, Yan-Jiang; Xie, Xi-Sheng; Feng, Sheng-Gang; Long, Qiong-Xian; Ai, Na; Wang, Bao-Fu

    2014-07-01

    To identify conditions that may improve the successful rate of STZ-induced rat models of diabetes mellitus (DM). 100 male SD rats were randomly divided into control group (n = 10) and experimental group (n = 90). Rats in the experimental group were treated with intraperitoneal injection of STZ 65 mg/kg once, and were then categorized into succeeded DM model group and failed group. Their body masses and levels of fasting blood glucose (FBG), urine glucose (UG), urine protein (UP), urine routine, renal function, liver function, blood lipids and kidney hypertrophy index (KHI) were monitored and compared. Dead rats were dissected to observe diseased organs. Pathological changes of those diseased organs were examined by HE staining. DM rat models were established through a single intraperitoneal injection of STZ, with a success rate of 58.89%. During the experiment, 43.33% of rats died. Compared with the rats in the failed group, the DM rat models had significantly higher levels of body mass, food intake, water intake, urine output, FBG, creatinine, blood urea nitrogen, KHI, urinary tract infections, and mortality; but lower levels of total protein, albumin and cholesterol and triglyceride (P causes of 11 dead rats were not clear. DM rat models can be established through a single intraperitoneal injection of STZ 65 mg/kg, but with high mortality rate. The deaths may be associated with infection, malnutrition, suffocation of lymphatic circulation, toxicity of STZ, and changes in environmental and climate conditions.

  1. 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.

  2. Spatial memory impairments in a prediabetic rat model.

    Science.gov (United States)

    Soares, E; Prediger, R D; Nunes, S; Castro, A A; Viana, S D; Lemos, C; De Souza, C M; Agostinho, P; Cunha, R A; Carvalho, E; Fontes Ribeiro, C A; Reis, F; Pereira, F C

    2013-10-10

    Diabetes is associated with an increased risk for brain disorders, namely cognitive impairments associated with hippocampal dysfunction underlying diabetic encephalopathy. However, the impact of a prediabetic state on cognitive function is unknown. Therefore, we now investigated whether spatial learning and memory deficits and the underlying hippocampal dysfunction were already present in a prediabetic animal model. Adult Wistar rats drinking high-sucrose (HSu) diet (35% sucrose solution during 9 weeks) were compared to controls' drinking water. HSu rats exhibited fasting normoglycemia accompanied by hyperinsulinemia and hypertriglyceridemia in the fed state, and insulin resistance with impaired glucose tolerance confirming them as a prediabetic rodent model. HSu rats displayed a poorer performance in hippocampal-dependent short- and long-term spatial memory performance, assessed with the modified Y-maze and Morris water maze tasks, respectively; this was accompanied by a reduction of insulin receptor-β density with normal levels of insulin receptor substrate-1 pSer636/639, and decreased hippocampal glucocorticoid receptor levels without changes of the plasma corticosterone levels. Importantly, HSu animals exhibited increased hippocampal levels of AMPA and NMDA receptor subunits GluA1 and GLUN1, respectively, whereas the levels of protein markers related to nerve terminals (synaptophysin) and oxidative stress/inflammation (HNE, RAGE, TNF-α) remained unaltered. These findings indicate that 9 weeks of sucrose consumption resulted in a metabolic condition suggestive of a prediabetic state, which translated into short- and long-term spatial memory deficits accompanied by alterations in hippocampal glutamatergic neurotransmission and abnormal glucocorticoid signaling. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  3. Regional 4-D modeling of the ionospheric electron density

    Science.gov (United States)

    Schmidt, M.; Bilitza, D.; Shum, C. K.; Zeilhofer, C.

    2008-08-01

    The knowledge of the electron density is the key point in correcting ionospheric delays of electromagnetic measurements and in studying the ionosphere. During the last decade GNSS, in particular GPS, has become a promising tool for monitoring the total electron content (TEC), i.e., the integral of the electron density along the ray-path between the transmitting satellite and the receiver. Hence, geometry-free GNSS measurements provide informations on the electron density, which is basically a four-dimensional function depending on spatial position and time. In addition, these GNSS measurements can be combined with other available data including nadir, over-ocean TEC observations from dual-frequency radar altimetry (T/P, JASON, ENVISAT), and TECs from GPS-LEO occultation systems (e.g., FORMOSAT-3/COSMIC, CHAMP) with heterogeneous sampling and accuracy. In this paper, we present different multi-dimensional approaches for modeling spatio-temporal variations of the ionospheric electron density. To be more specific, we split the target function into a reference part, computed from the International Reference Ionosphere (IRI), and an unknown correction term. Due to the localizing feature of B-spline functions we apply tensor-product spline expansions to model the correction term in a certain multi-dimensional region either completely or partly. Furthermore, the multi-resolution representation derived from wavelet analysis allows monitoring the ionosphere at different resolutions levels. For demonstration we apply three approaches to electron density data over South America.

  4. Loss of Glial Cells of the Hippocampus in a Rat Model of Post-traumatic Stress Disorder.

    Science.gov (United States)

    Han, Fang; Xiao, Bing; Wen, Lili

    2015-05-01

    Single prolonged stress (SPS) rats is a rodent model of post traumatic stress disorder (PTSD). Abnormal hippocampal morphology and function were found in the PTSD patients. Our previous study has shown that SPS induce loss of hippocampal neurons. But the effects of SPS on glial cells in the hippocampus have not been evaluated. In the present study, wistar male rats were examined at 1, 4, 7, or 14 days after SPS. The morris water maze were performed to examine hippocampal-dependent cognition. The neurometabolite and morphological change in the hippocampal neurons and glial cells were investigated using in vivo proton magnetic resonance spectroscopy and transmission electron microscopy. Immunofluorescence histochemistry and western blotting for Glial fibrillary acidic protein (GFAP) was used to evaluate change of astrocytes. SPS rats showed increased escape latency. The significant reductions in N-acetylaspartate, creatine, and choline-containing compounds in the hippocampus of SPS rats were found. Moreover, abnormal morphological characteristics in glial cells of the SPS group were observed. The number of GFAP-positive cells, intensity of GFAP-ir and GFAP-protein within the hippocampus increased after SPS at 1 day, and then decreased. The findings suggested that SPS induced loss/impairment of glial cell in the hippocampus; also loss of glial cells may due to the astrocytes reduction within the hippocampus of SPS rats.

  5. Neuroprotective effects of propofol, thiopental, etomidate, and midazolam in fetal rat brain in ischemia-reperfusion model.

    Science.gov (United States)

    Harman, Ferhat; Hasturk, Askin Esen; Yaman, Mehmet; Arca, Turkan; Kilinc, Kamer; Sargon, Mustafa Fevzi; Kaptanoglu, Erkan

    2012-07-01

    The aim of this study was to investigate the neuroprotective effects of propofol, thiopental, etomidate, and midazolam as anesthetic drugs in fetal rat brain in the ischemia-reperfusion (IR) model. Pregnant rats of day 19 were randomly allocated into eight groups. Fetal brain ischemia was induced by clamping the utero-ovarian artery bilaterally for 30 min and reperfusion was achieved by removing the clamps for 60 min. In the control group, fetal rat brains were obtained immediately after laparotomy. In the sham group, fetal rat brains were obtained 90 min after laparotomy. In the IR group, IR procedure was performed. No treatment was given in the IR group. One milliliter intralipid solution, 40 mg/kg propofol, 3 mg/kg thiopental, 0.1 mg/kg etomidate, and 3 mg/kg midazolam was administered intraperitoneally in the vehicle group, propofol group, thiopental group, etomidate group, and midazolam group, respectively, 20 min before IR procedure. At the end of the reperfusion period, the whole brains of the fetal rats were removed for evaluation of thiobarbituric acid reactive substances and for examination by electron microscopy. According to lipid peroxidation data, all the anesthetic drugs provide neuroprotection; however, ultrastructural findings and mitochondrial scoring confirms that only propofol and midazolam provides a strong neuroprotective effect. Propofol and midazolam may be used to protect fetal brain in case of acute fetal distress and hypoxic injury as a first choice anesthetic drug in cesarean delivery.

  6. 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.

  7. 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

  8. Modelling and simulation of beam formation in electron guns

    International Nuclear Information System (INIS)

    Sabchevski, S.; Barbarich, I.

    1996-01-01

    This paper describes a new PC version of the software package GUN-EBT for computer simulation of beam formation in rotationally symmetric electron guns with thermionic cathodes. It is based on a self-consistent physical model which takes into account the beam space charge and the initial velocity effects. The theoretical framework used for both the formulation of the model and for the interpretation of the results of numerical experiments is the formalism of the charged particle dynamics in phase space. This enables not only a trajectory analysis (ray tracing) but also a phase-space analysis of beams to be performed. The package can be used as an effective tool for computer aided design and optimization of electron guns in various electron-optical systems. The operation of the package is illustrated with a typical example. (orig.)

  9. Modelling and simulation of beam formation in electron guns

    Energy Technology Data Exchange (ETDEWEB)

    Sabchevski, S. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. po Elektronika; Mladenov, G. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. po Elektronika; Titov, A. [St. Petersburg State Electrotechnical University, St. Petersburg (Russian Federation); Barbarich, I. [St. Petersburg State Electrotechnical University, St. Petersburg (Russian Federation)

    1996-11-01

    This paper describes a new PC version of the software package GUN-EBT for computer simulation of beam formation in rotationally symmetric electron guns with thermionic cathodes. It is based on a self-consistent physical model which takes into account the beam space charge and the initial velocity effects. The theoretical framework used for both the formulation of the model and for the interpretation of the results of numerical experiments is the formalism of the charged particle dynamics in phase space. This enables not only a trajectory analysis (ray tracing) but also a phase-space analysis of beams to be performed. The package can be used as an effective tool for computer aided design and optimization of electron guns in various electron-optical systems. The operation of the package is illustrated with a typical example. (orig.).

  10. 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.

  11. 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

  12. 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…

  13. 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 v...

  14. 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)

  15. Metformin and atorvastatin reduce adhesion formation in a rat uterine horn model.

    Science.gov (United States)

    Yilmaz, Bulent; Aksakal, Orhan; Gungor, Tayfun; Sirvan, Levent; Sut, Necdet; Kelekci, Sefa; Soysal, Sunullah; Mollamahmutoglu, Leyla

    2009-03-01

    The aim of the present study was to determine whether atorvastatin and metformin are effective in preventing adhesions in a rat uterine horn model. A total of 40 non-pregnant, female Wistar albino rats, weighing 180-210 g, were used as a model for post-operative adhesion formation. The rats were randomized into four groups after seven standard lesions were inflicted in each uterine horn and lower abdominal sidewall using bipolar cauterization. The rats were given atorvastatin 2.5 mg/kg/day, p.o. (10 rats), atorvastatin 30 mg/kg/day, p.o. (10 rats), metformin 50 mg/kg/day, p.o. (10 rats) and no treatment was applied in the control group (10 rats). The animals were killed 2 weeks later and adhesions were scored both clinically and pathologically by authors blinded to groups. One rat in the control group died before the end of the 2 week period. Total clinical adhesion scores regarding extent, severity and degree of adhesions and histopathological findings including inflammation and fibrosis were significantly lower in the metformin (P < 0.001 and P < 0.01, respectively) and atorvastatin 30 mg/kg/day (P < 0.001 and P < 0.01, respectively) groups when compared with control group. Metformin and atorvastatin are both effective for prevention of adhesion formation in a rat uterine horn model.

  16. Hemorheology index changes in a rat acute blood stasis model: a ...

    African Journals Online (AJOL)

    Hemorheology index changes in a rat acute blood stasis model: a systematic review and meta-analysis. ... Chinese National Knowledge Infrastructure database (CNKI), Chinese Medical Journal Database (CMJD), Chinese Biology Medicine disc (CBM), Wanfang database, and PubMed for studies of rat blood stasis models; ...

  17. Teriparatide and the treatment of bisphosphonate-related osteonecrosis of the jaw: a rat model

    NARCIS (Netherlands)

    Ersan, N.; van Ruijven, L.J.; Bronckers, A.L.J.J.; Olgaç, V.; Ìlgüy, D.; Everts, V.

    2014-01-01

    Objectives: The objectives of this study were to establish a bisphosphonate-related osteonecrosis of the jaw (BRONJ) rat model and to analyse the effects of teriparatide (TP) on this model. Methods: Sprague-Dawley rats were divided into three groups: I—zoledronic acid (ZA, n = 10); II—ZA and

  18. Modeling of magnetic components for power electronic converters

    Science.gov (United States)

    Hranov, Tsveti; Hinov, Nikolay

    2017-12-01

    The paper presents the modelling of magnetic components, used in the power electronic devices. Non-linear inductor and transformer are presented. During the design stage are taken into account that the converters are operated with non-sinusoidal currents and voltages. The models are realized in the MATLAB environment and their verification is done using computer simulations. The advantages of these models against the existing models are that relations between the parameters are formalized and this way the computational procedure is significantly faster. This is important in the cases when the quasi-steady-state regime in devices comes significantly slower and the investigations are requiring long simulation times.

  19. 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.)

  20. Altered state of primordial follicles in neonatal and early infantile rats due to maternal hypothyroidism: Light and electron microscopy approach.

    Science.gov (United States)

    Danilović Luković, Jelena; Korać, Aleksandra; Milošević, Ivan; Lužajić, Tijana; Puškaš, Nela; Kovačević Filipović, Milica; Radovanović, Anita

    2016-11-01

    Thyroid hormones (TH) are one of the key factors for normal prenatal development in mammals. Previously, we showed that subclinical maternal hypothyroidism leads to premature atresia of ovarian follicles in female rat offspring in the pre-pubertal and pubertal periods. The influence of decreased concentration of TH on primordial follicles pool formation during neonatal and early infantile period of rat pups was not investigated previously. Maternal hypothyroidism during pregnancy has irreversible negative influence on primordial follicles pool formation and population of resting oocytes in female rat offspring. The study was done on neonatal and early infantile control (n-10) and hypothyroid (n-10) female rat pups derived from control (n-6) and propylthiouracil (PTU) treated pregnant dams (n-6), respectively. Ovaries of all pups were removed and processed for light and transmission electron microscopy (TEM). Number of nests, oogonia and oocytes per nest, primordial, primary, secondary and preantral follicles were determined. Screening for overall calcium presence in ovarian tissue was done using Alizarin red staining. Morphology and volume density of nucleus, mitochondria and smooth endoplasmic reticulum (sER) in the oocytes in primordial follicles was also assessed. Caspase-3 and terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL), both markers for apoptosis, and proliferating cell nuclear antigen (PCNA) for proliferation were determined in oocytes and granulosa cells in different type of follicles. In neonatal period, ovaries of hypothyroid pups had a decreased number of oogonia, oocytes and nests, an increased number of primordial follicles and a decreased number of primary and secondary follicles, while in early infantile period, increased number of primary, secondary and preantral follicles were found. Alizarin red staining was intense in hypothyroid neonatal rats that also had the highest content of dilated sER. Number of mitochondria with

  1. 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.

    2016-10-01

    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%.

  2. 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.

  3. Modafinil improves monocrotaline-induced pulmonary hypertension rat model.

    Science.gov (United States)

    Lee, Hyeryon; Kim, Kwan Chang; Cho, Min-Sun; Suh, Suk-Hyo; Hong, Young Mi

    2016-07-01

    Pulmonary arterial hypertension (PAH) progressively leads to increases in pulmonary vasoconstriction. Modafinil plays a role in vasorelaxation and blocking KCa3.1 channel with a result of elevating intracellular cyclic adenosine monophosphate (cAMP) levels. The purpose of this study is to evaluate the effects on modafinil in monocrotaline (MCT)-induced PAH rat. The rats were separated into three groups: the control group, the monocrotaline (M) group (MCT 60 mg/kg), and the modafinil (MD) group (MCT 60 mg/kg + modafinil). Reduced right ventricular pressure (RVP) was observed in the MD group. Right ventricular hypertrophy was improved in the MD group. Reduced number of intra-acinar pulmonary arteries and medial wall thickness were noted in the MD group. After the administration of modafinil, protein expressions of endothelin-1 (ET-1), endothelin receptor A (ERA) and KCa3.1 channel were significantly reduced. Modafinil suppressed pulmonary artery smooth muscle cell (PASMC) proliferation via cAMP and KCa3.1 channel. Additionally, we confirmed protein expressions such as Bcl-2-associated X, vascular endothelial growth factor, tumor necrosis factor-α, and interleukin-6 were reduced in the MD group. Modafinil improved PAH by vasorelaxation and a decrease in medial thickening via ET-1, ERA, and KCa3.1 down regulation. This is a meaningful study of a modafinil in PAH model.

  4. Bone healing models in rat tibia after different injuries.

    Science.gov (United States)

    Hussar, P; Piirsoo, A; Märtson, A; Toom, A; Haviko, T; Hussar, U

    2001-01-01

    Gradual elaboration of an adequate and efficient multistage method for experimental remodelling of specific wound healing process--bone repair. Comparison of clinical characteristics with the results of microanatomy, histology, electronmicroscopy and computer morphometry. An investigation of posttraumatic bone repair after internal fracture, excision and cortical perforation was carried out on 142 young adult male Wistar rats. The repair was studied in normal and affected animals (exercises, immobilization, isolation of periost) at 1-42 days after operation. The posttraumatic bone callus development and the related soft tissue repair, likewise the continuous remodelling, is an ordinary process of osteohisto- and organogenese. In trained rats the blood supply and bone formation is increased, whereas in immobilized animals it is inhibited and destroyed (osteoporose, pseudoarthrosis). After the injury some characteristics of bone repair histogenese will be became evident (after the perforation the primary endosteal and secondary periosteal ossification, inhibition of endosteal bone repair after the isolation of periost etc.). The posttraumatic bone healing, like embryohistogenese, has similar repair stages in all models of the experiments as well as similar tissue and cell responses (callus formation, its replacement, bone remodelling, etc.). However, the repair process in general (order of chondrous and/or bone callus stages, etc.) is variable and dependent on the mode and degree of injury. The use of bone cortex perforation in wound healing study is more recommendable as compared to internal fracture and excision (possibility of in situ study the periost and callus tissue compartments in bone repair machinery separately).

  5. 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

  6. 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.

  7. 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.

  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

    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. Transformer Model in Wide Frequency Bandwidth for Power Electronics Systems

    Directory of Open Access Journals (Sweden)

    Carlos Gonzalez-Garcia

    2013-01-01

    Full Text Available The development of the smart grids leads to new challenges on the power electronics equipment and power transformers. The use of power electronic transformer presents several advantages, but new problems related with the application of high frequency voltage and current components come across. Thus, an accurate knowledge of the transformer behavior in a wide frequency range is mandatory. A novel modeling procedure to relate the transformer physical behavior and its frequency response by means of electrical parameters is presented. Its usability is demonstrated by an example where a power transformer is used as filter and voltage reducer in an AC-DC-AC converter.

  10. ELECTRON AVALANCHE MODEL OF DIELECTRIC-VACUUM SURFACE BREAKDOWN

    Energy Technology Data Exchange (ETDEWEB)

    Lauer, E J

    2007-02-21

    The model assumes that an 'initiating event' results in positive ions on the surface near the anode and reverses the direction of the normal component of electric field so that electrons in vacuum are attracted to the dielectric locally. A sequence of surface electron avalanches progresses in steps from the anode to the cathode. For 200 kV across 1 cm, the spacing of avalanches is predicted to be about 13 microns. The time for avalanches to step from the anode to the cathode is predicted to be about a ns.

  11. 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.

  12. 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)

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

    Directory of Open Access Journals (Sweden)

    Ghupurjan Gheni

    2015-01-01

    Full Text Available 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.

  14. Impaired voluntary wheel running behavior in the unilateral 6-hydroxydopamine rat model of Parkinson's disease.

    Science.gov (United States)

    Pan, Qi; Zhang, Wangming; Wang, Jinyan; Luo, Fei; Chang, Jingyu; Xu, Ruxiang

    2015-02-01

    The aim of this study was to investigate voluntary wheel running behavior in the unilateral 6-hydroxydopamine (6-OHDA) rat model. Male Sprague-Dawley rats were assigned to 2 groups : 6-OHDA group (n=17) and control group (n=8). The unilateral 6-OHDA rat model was induced by injection of 6-OHDA into unilateral medial forebrain bundle using a stereotaxic instrument. Voluntary wheel running activity was assessed per day in successfully lesioned rats (n=10) and control rats. Each behavioral test lasted an hour. The following parameters were investigated during behavioral tests : the number of running bouts, the distance moved in the wheel, average peak speed in running bouts and average duration from the running start to the peak speed. The number of running bouts and the distance moved in the wheel were significantly decreased in successfully lesioned rats compared with control rats. In addition, average peak speed in running bouts was decreased, and average duration from the running start to the peak speed was increased in lesioned animals, which might indicate motor deficits in these rats. These behavioral changes were still observed 42 days after lesion. Voluntary wheel running behavior is impaired in the unilateral 6-OHDA rat model and may represent a useful tool to quantify motor deficits in this model.

  15. 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.

  16. Hyperactivity and hypoactivity in a rat model of Huntington's disease: the systemic 3-nitropropionic acid model.

    Science.gov (United States)

    Borlongan, C V; Koutouzis, T K; Freeman, T B; Hauser, R A; Cahill, D W; Sanberg, P R

    1997-08-01

    The present study proposes the use of systemic 3-nitropropionic acid (3-NP) treatment in rats as a model of Huntington's disease (HD). The systemic 3-NP model involves chronic injection of low dose intraperitoneal (i.p.) injections of 3-NP to rats once every 4 days over a period of time. Evidence from our experimental studies suggests that manipulating the number of injections can result in either increased nocturnal spontaneous locomotor activity (hyperactivity) or nocturnal akinesia (hypoactivity) [1]. For example, two injections of 3-NP (using the treatment of one injection every 4 days) result in hyperactivity, while four injections or more of 3-NP lead to hypoactivity [1]. The locomotor activity is recorded by Digiscan locomotor activity monitors [11]. The observation of these two types of locomotor activity is unique since no excitotoxin model has replicated a two-stage progression of a HD-like behavioral alteration. Most studies using excitotoxins like quinolinic acid (QA) and kainic acid (KA) have only reproduced the hyperactivity stage [4,5,7]. With the systemic 3-NP model, investigations into at least two stages of the disease are made possible. This allows for better assessment of intervention strategies such as neural transplants across different stages of the disease. The systemic 3-NP rat model is believed to be an improved animal model of HD.

  17. 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.

  18. 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...

  19. Treatment of rat Walker-256 carcinosarcoma with photodynamic therapy and endotoxin irradiated with high-energy electrons

    Science.gov (United States)

    Dima, Vasile F.; Vasiliu, Virgil V.; Laky, Dezideriu; Ionescu, Mircea D.; Dima, Stefan V.

    1994-03-01

    Experiments were performed on five batches of Wistar inbred rats with Walker-256 carcinosarcoma receiving sole treatment photodynamic therapy (PDT), irradiated endotoxin (R-LPS), native-endotoxin (N-LPS), or associated therapy (PDT + R-LPS) and the control batch (saline) consisted of animals with untreated Walker-256 tumors. The results were as follows: the sole treatment (PDT, R-LPS, N-LPS) gave survival rates between 56.3 and 60.7% and cure rates ranging from 32.1 to 37.5%. The `combined' therapy in multiple doses increased significantly (88.6%) the survival rate of tumor bearing rats as well as the highest incidence of complete tumor regression (71.4%). This work demonstrates that `combined' photodynamic and immunotherapy with irradiated endotoxin stimulates cell-mediated antitumoral activity and induces changes in the tumoral incidence in Walker-256 carcinosarcoma in the rat model.

  20. Sleep Changes in a Rat Prenatal Stress Model of Depression

    DEFF Research Database (Denmark)

    Skoven, Christian; Sickman, Helle M.; Bastlund, Jesper Frank

    Major depression is one of the most frequently occurring mental health disorders, but is characterized by diverse symptomatology. Sleep disturbances, however, are commonplace in depressive patients. These alterations include increased duration of Rapid Eye Movement Sleep (REMS) and increased sleep...... fragmentation. Stressful life events during the second trimester of human pregnancy increase the risk of depression in the offspring. Similarly, rodents exposed to prenatal stress (PNS) during gestation express depression- like behavioral changes. Accordingly, we investigated sleep changes in a rat PNS model...... determination of sleep-wakefulness state. As traumatic episodes can trigger episodes of clinical depression, we also investigated effects of an acute stressor during the recording period. PNS animals (n=21) had an 82% increase in amount of REMS (11.6±1.4% vs 6.3±0.9%; p

  1. [Changes of urinary proteins in a bacterial meningitis rat model].

    Science.gov (United States)

    Ni, Yanying; Zhang, Fanshuang; An, Manxia; Gao, Youhe

    2017-07-25

    Unlike cerebrospinal fluid or blood, urine accumulates metabolic changes of the body and has the potential to be a promising source of early biomarkers discovery. Bacterial meningitis is a major cause of illness among neonates and children worldwide. In this study, we used Escherichia coli-injected rat model to mimic meningitis and collected urine samples on day 1 and day 3. We used two different methods to digest proteins and analyzed peptides by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). We identified 17 and 20 differential proteins by two methods respectively on day 1, and 5 differential proteins by filter-aided digestion method on day 3. Finding these differential proteins laid a foundation to further explore biomarkers of bacterial meningitis.

  2. 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.

  3. Modeling interpopulation dispersal by banner-tailed kangaroo rats

    Science.gov (United States)

    Skvarla, J.L.; Nichols, J.D.; Hines, J.E.; Waser, P.M.

    2004-01-01

    Many metapopulation models assume rules of population connectivity that are implicitly based on what we know about within-population dispersal, but especially for vertebrates, few data exist to assess whether interpopulation dispersal is just within-population dispersal "scaled up." We extended existing multi-stratum mark-release-recapture models to incorporate the robust design, allowing us to compare patterns of within- and between-population movement in the banner-tailed kangaroo rat (Dipodomys spectabilis). Movement was rare among eight populations separated by only a few hundred meters: seven years of twice-annual sampling captured >1200 individuals but only 26 interpopulation dispersers. We developed a program that implemented models with parameters for capture, survival, and interpopulation movement probability and that evaluated competing hypotheses in a model selection framework. We evaluated variants of the island, stepping-stone, and isolation-by-distance models of interpopulation movement, incorporating effects of age, season, and habitat (short or tall grass). For both sexes, QAICc values clearly favored isolation-by-distance models, or models combining the effects of isolation by distance and habitat. Models with probability of dispersal expressed as linear-logistic functions of distance and as negative exponentials of distance fit the data equally well. Interpopulation movement probabilities were similar among sexes (perhaps slightly biased toward females), greater for juveniles than adults (especially for females), and greater before than during the breeding season (especially for females). These patterns resemble those previously described for within-population dispersal in this species, which we interpret as indicating that the same processes initiate both within- and between-population dispersal.

  4. A model of calcium homeostasis in the rat.

    Science.gov (United States)

    Granjon, David; Bonny, Olivier; Edwards, Aurélie

    2016-11-01

    We developed a model of calcium homeostasis in the rat to better understand the impact of dysfunctions such as primary hyperparathyroidism and vitamin D deficiency on calcium balance. The model accounts for the regulation of calcium intestinal uptake, bone resorption, and renal reabsorption by parathyroid hormone (PTH), vitamin D 3 , and Ca 2+ itself. It is the first such model to incorporate recent findings regarding the role of the calcium-sensing receptor (CaSR) in the kidney, the presence of a rapidly exchangeable pool in bone, and the delayed response of vitamin D 3 synthesis. Accounting for two (fast and slow) calcium storage compartments in bone allows the model to properly predict the effects of bisphophonates on the plasma levels of Ca 2+ ([Ca 2+ ] p ), PTH, and vitamin D 3 Our model also suggests that Ca 2+ exchange rates between plasma and the fast pool vary with both sex and age, allowing [Ca 2+ ] p to remain constant in spite of sex- and age-based hormonal and other differences. Our results suggest that the inconstant hypercalciuria that is observed in primary hyperparathyroidism can be attributed in part to counterbalancing effects of PTH and CaSR in the kidney. Our model also correctly predicts that calcimimetic agents such as cinacalcet bring down [Ca 2+ ] p to within its normal range in primary hyperparathyroidism. In addition, the model provides a simulation of CYP24A1 inactivation that leads to a situation reminiscent of infantile hypercalcemia. In summary, our model of calcium handling can be used to decipher the complex regulation of calcium homeostasis. Copyright © 2016 the American Physiological Society.

  5. Histopathological nature of myofascial trigger points at different stages of recovery from injury in a rat model.

    Science.gov (United States)

    Zhang, Hui; Lü, Jiao-Jiao; Huang, Qiang-Min; Liu, Lin; Liu, Qing-Guang; Eric, Opoku-Antwi

    2017-12-01

    To investigate the histopathological nature of myofascial trigger points (MTrPs) or spots (MTrSs) at different stages of recovery from injury in a rat model. Forty Sprague-Dawley rats were randomly divided into two groups: a control group (CG) and experimental group (EG). The CG was further randomly subdivided into CG1 and CG2 subgroups. The CG2 was used for palpating the taut band and CG1 as a blank. EG was subdivided into three groups according to recovery times: 4 weeks (4W), 8 weeks (8W) and 12 weeks (12W); these groups consisted of eight rats each. All CG rats received no intervention, whereas the intervention in EG rats was by a blunt strike to the vastus medialis and eccentric exercise for 8 weeks. The taut bands with spontaneous electrical activity were then detected in the muscle to guide a muscle biopsy. The histopathological findings were investigated under optical and electron microscopes in all groups. Under optical microscopy, the differently augmented sizes of round fibres (contracture knots) with deep staining in the transverse section and fusiform shapes in a longitudinal view were clearly seen in CG2 and EGs with a large diameter; the number of contracture knots was significantly more in EGs than in CGs. Under an electron microscope, the mitochondria in EGs significantly decreased with abnormal structures. The sarcomeres were significantly shortened in the 8W and 12W EGs. An injury can cause activation of MTrSs in a muscle and an activated level of MTrPs depending on the number of contracture knots in muscle with impaired energy production. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  6. 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.

  7. Differentiated analysis of orthodontic tooth movement in rats with an improved rat model and three-dimensional imaging.

    Science.gov (United States)

    Kirschneck, Christian; Proff, Peter; Fanghaenel, Jochen; Behr, Michael; Wahlmann, Ulrich; Roemer, Piero

    2013-12-01

    Rat models currently available for analysis of orthodontic tooth movement often lack differentiated, reliable and precise measurement systems allowing researchers to separately investigate the individual contribution of tooth tipping, body translation and root torque to overall displacement. Many previously proposed models have serious limitations such as the rather inaccurate analysis of the effects of orthodontic forces on rat incisors. We therefore developed a differentiated measurement system that was used within a rat model with the aim of overcoming the limitations of previous studies. The first left upper molar and the upper incisors of 24 male Wistar rats were subjected to a constant orthodontic force of 0.25 N by means of a NiTi closed coil spring for up to four weeks. The extent of the various types of tooth movement was measured optometrically with a CCD microscope camera and cephalometrically by means of cone beam computed tomography (CBCT). Both types of measurement proved to be reliable for consecutive measurements and the significant tooth movement induced had no harmful effects on the animals. Movement kinetics corresponded to known physiological processes and tipping and body movement equally contributed to the tooth displacement. The upper incisors of the rats were significantly deformed and their natural eruption was effectively halted. The results showed that our proposed measurement systems used within a rat model resolved most of the inadequacies of previous studies. They are reliable, precise and physiological tools for the differentiated analysis of orthodontic tooth movement while simultaneously preserving animal welfare. Copyright © 2013 Elsevier GmbH. All rights reserved.

  8. 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...

  9. In Situ Perfusion Model in Rat Colon for Drug Absorption Studies: Comparison with Small Intestine and Caco-2 Cell Model.

    Science.gov (United States)

    Lozoya-Agullo, Isabel; González-Álvarez, Isabel; González-Álvarez, Marta; Merino-Sanjuán, Matilde; Bermejo, Marival

    2015-09-01

    Our aim is to develop and to validate the in situ closed loop perfusion method in rat colon and to compare with small intestine and Caco-2 cell models. Correlations with human oral fraction absorbed (Fa) and human colon fraction absorbed (Fa_colon) were developed to check the applicability of the rat colon model for controlled release (CR) drug screening. Sixteen model drugs were selected and their permeabilities assessed in rat small intestine and colon, and in Caco-2 monolayers. Correlations between colon/intestine/Caco-2 permeabilities versus human Fa and human Fa_colon have been explored to check model predictability and to apply a BCS approach in order to propose a cut off value for CR screening. Rat intestine perfusion with Doluisio's method and single-pass technique provided a similar range of permeabilities demonstrating the possibility of combining data from different laboratories. Rat colon permeability was well correlated with Caco-2 cell-4 days model reflecting a higher paracellular permeability. Rat colon permeabilities were also higher than human colon ones. In spite of the magnitude differences, a good sigmoidal relationship has been shown between rat colon permeabilities and human colon fractions absorbed, indicating that rat colon perfusion can be used for compound classification and screening of CR candidates. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  10. 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.

  11. Advanced electron crystallography through model-based imaging

    Science.gov (United States)

    Van Aert, Sandra; De Backer, Annick; Martinez, Gerardo T.; den Dekker, Arnold J.; Van Dyck, Dirk; Bals, Sara; Van Tendeloo, Gustaaf

    2016-01-01

    The increasing need for precise determination of the atomic arrangement of non-periodic structures in materials design and the control of nanostructures explains the growing interest in quantitative transmission electron microscopy. The aim is to extract precise and accurate numbers for unknown structure parameters including atomic positions, chemical concentrations and atomic numbers. For this purpose, statistical parameter estimation theory has been shown to provide reliable results. In this theory, observations are considered purely as data planes, from which structure parameters have to be determined using a parametric model describing the images. As such, the positions of atom columns can be measured with a precision of the order of a few picometres, even though the resolution of the electron microscope is still one or two orders of magnitude larger. Moreover, small differences in average atomic number, which cannot be distinguished visually, can be quantified using high-angle annular dark-field scanning transmission electron microscopy images. In addition, this theory allows one to measure compositional changes at interfaces, to count atoms with single-atom sensitivity, and to reconstruct atomic structures in three dimensions. This feature article brings the reader up to date, summarizing the underlying theory and highlighting some of the recent applications of quantitative model-based transmisson electron microscopy. PMID:26870383

  12. Advanced electron crystallography through model-based imaging

    Directory of Open Access Journals (Sweden)

    Sandra Van Aert

    2016-01-01

    Full Text Available The increasing need for precise determination of the atomic arrangement of non-periodic structures in materials design and the control of nanostructures explains the growing interest in quantitative transmission electron microscopy. The aim is to extract precise and accurate numbers for unknown structure parameters including atomic positions, chemical concentrations and atomic numbers. For this purpose, statistical parameter estimation theory has been shown to provide reliable results. In this theory, observations are considered purely as data planes, from which structure parameters have to be determined using a parametric model describing the images. As such, the positions of atom columns can be measured with a precision of the order of a few picometres, even though the resolution of the electron microscope is still one or two orders of magnitude larger. Moreover, small differences in average atomic number, which cannot be distinguished visually, can be quantified using high-angle annular dark-field scanning transmission electron microscopy images. In addition, this theory allows one to measure compositional changes at interfaces, to count atoms with single-atom sensitivity, and to reconstruct atomic structures in three dimensions. This feature article brings the reader up to date, summarizing the underlying theory and highlighting some of the recent applications of quantitative model-based transmisson electron microscopy.

  13. Electronic Model of a Ferroelectric Field Effect Transistor

    Science.gov (United States)

    MacLeod, Todd C.; Ho, Fat Duen; Russell, Larry (Technical Monitor)

    2001-01-01

    A pair of electronic models has been developed of a Ferroelectric Field Effect transistor. These models can be used in standard electrical circuit simulation programs to simulate the main characteristics of the FFET. The models use the Schmitt trigger circuit as a basis for their design. One model uses bipolar junction transistors and one uses MOSFET's. Each model has the main characteristics of the FFET, which are the current hysterisis with different gate voltages and decay of the drain current when the gate voltage is off. The drain current from each model has similar values to an actual FFET that was measured experimentally. T'he input and o Output resistance in the models are also similar to that of the FFET. The models are valid for all frequencies below RF levels. No attempt was made to model the high frequency characteristics of the FFET. Each model can be used to design circuits using FFET's with standard electrical simulation packages. These circuits can be used in designing non-volatile memory circuits and logic circuits and is compatible with all SPICE based circuit analysis programs. The models consist of only standard electrical components, such as BJT's, MOSFET's, diodes, resistors, and capacitors. Each model is compared to the experimental data measured from an actual FFET.

  14. Evaluation of borate bioactive glass scaffolds with different pore sizes in a rat subcutaneous implantation model.

    Science.gov (United States)

    Deliormanli, Aylin M; Liu, Xin; Rahaman, Mohamed N

    2014-01-01

    Borate bioactive glass has been shown to convert faster and more completely to hydroxyapatite and enhance new bone formation in vivo when compared to silicate bioactive glass (such as 45S5 and 13-93 bioactive glass). In this work, the effects of the borate glass microstructure on its conversion to hydroxyapatite (HA) in vitro and its ability to support tissue ingrowth in a rat subcutaneous implantation model were investigated. Bioactive borate glass scaffolds, designated 13-93B3, with a grid-like microstructure and pore widths of 300, 600, and 900 µm were prepared by a robocasting technique. The scaffolds were implanted subcutaneously for 4 weeks in Sprague Dawley rats. Silicate 13-93 glass scaffolds with the same microstructure were used as the control. The conversion of the scaffolds to HA was studied as a function of immersion time in a simulated body fluid. Histology and scanning electron microscopy were used to evaluate conversion of the bioactive glass implants to hydroxyapatite, as well as tissue ingrowth and blood vessel formation in the implants. The pore size of the scaffolds was found to have little effect on tissue infiltration and angiogenesis after the 4-week implantation.

  15. Photochemically induced spinal ischaemia: a model of spinal cord trauma in the rat

    Science.gov (United States)

    Olby, Natasha J.; Blakemore, W. F.

    1995-05-01

    Focal thrombosis was induced in the dorsal funiculus of the rat spinal cord by exposing the cord to light following intravenous injection of the photoactive dye, rose bengal. The light source was a 599 standing wave dye laser, pumped by an Innova 70 - 4 argon ion laser (Coherent Ltd, Cambridge, UK) and the light was delivered to the operative site via an optical fiber. The histological characteristics of the development and resolution of the lesion have been studied. Forty rats were examined with light and electron microscopy at various time points between 30 minutes and one month after irradiation and the lesion length was measured. Platelet aggregation, increased extracellular space in the white matter and vacuolation of the neurones and glia of the grey matter were present 30 minutes after injury. Progressive necrosis of the white and grey matter developed over the subsequent 24 hours to produce a fusiform lesion that occupied the dorsal funiculus and dorsal horns of the spinal cord at its center and tapered cranially and caudally along the dorsal columns for a total distance of seven millimeters. By one month after injury the area of necrosis had become a cyst lined by astrocytes ventrolaterally and meningeal cells dorsally. Measurements of lesion length showed a variability of 26%. This model of spinal cord trauma produces a lesion that is sufficiently reproducible to be suitable for performing studies aimed at tissue preservation and repair.

  16. Ethyl pyruvate reduces hepatic mitochondrial swelling and dysfunction in a rat model of sepsis.

    Science.gov (United States)

    Jiang, Zhiyi; Li, Xiaoyue; Lin, Zongqin; Chen, Juan; Guan, Xiangdong; Chen, Minying

    2015-01-01

    Sepsis causes mitochondrial oxidative injury and swelling. Ethyl pyruvate (EP) is a cytoprotective agent, while aquaporin-8 (AQP8) is a mitochondrial water channel that can induce mitochondrial swelling. We assessed whether EP protects mitochondria during sepsis, and whether AQP8 contributes to the underlying mechanisms. A cecal ligation and puncture (CLP) sepsis model was established in Sprague-Dawley rats, randomized to 3 groups: sham (n=20), CLP (n=59) and CLP+EP (n=51). All rats received postoperative intraperitoneal fluid resuscitation (30 ml/kg); the CLP+EP group also received intraperitoneal EP (100 mg/kg). Survival was assessed at 24 hours. Hepatic mitochondrial ultrastructure was characterized by electron microscopy. The membrane potential of isolated hepatic mitochondria was determined using JC-1 and flow cytometry. Mitochondrial AQP8 expression and cytochrome C (Cyt C) release were measured by Western blotting (values normalized to ß-actin). Survival in the sham, CLP and CLP+EP groups was 100%, 21% and 41%, respectively. Mitochondrial cross-sectional area was smaller in the CLP+EP group than in the CLP group (0.231±0.110 vs. 0.641±0.460 µm(2); Psepsis outcome by targeting the mitochondrion, possibly through modulation of AQP8 expression.

  17. [Effect of ethanol extract from Matbuhi Aftimun on blood lipide level in rat hyperilpldemla model].

    Science.gov (United States)

    Islam, Rabigul; Mamat, Yultuz; Rapkat, Haximjan

    2010-07-01

    To investigate the acute toxicity, lipid reducing effect and mechanism of action of ethanol extracts of Matbuhi Aftimun (E-MA), a classic prescription of Uighur medicine, on hyperlipidemia rat model. The LD50 or maximum tolerance of rats to E-MA was determined by simplified probit method. Hyperlipidemia rat model was established in SD rats by feeding high lipid emulsion, then E-MA at different dosages (0.80 g/kg, 1.60 g/kg and 3.20 g/kg) was given orally to them. The effects of E-MA on model rats' serum lipids, including total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C), high density lipoprotein-cholesterol (HDL-C), triglyceride (TG), were observed. And its effects on malondialdehydec (MDA) content, superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), total lipase, including lipoprotein lipase (LPL) and hepato-lipase (HL) activities in the liver homogenate were assayed. The maximum tolerance of rats to E-MA was 64 g (crude drug)/kg. Compared with the hyperlipidemia model rat, the blood TC level was lower (P 0.05), also on the levels of SOD, GSH-PX and total lipase in the liver homogenate (P > 0.05). E-MA shows a serum TC reducing effect on hyperlipidemia rat model with low toxicity in mice.

  18. Quantum entanglement in two-electron atomic models

    Energy Technology Data Exchange (ETDEWEB)

    Manzano, D; Plastino, A R; Dehesa, J S [Instituto Carlos I de Fisica Teorica y Computacional, Universidad de Granada, Granada E-18071 (Spain); Koga, T, E-mail: arplastino@ugr.e [Applied Chemistry Research Unit, Graduate School of Engineering, Muroran Institute of Technology, Muroran, Hokkaido 050-8585 (Japan)

    2010-07-09

    We explore the main entanglement properties exhibited by the eigenfunctions of two exactly soluble two-electron models, the Crandall atom and the Hooke atom, and compare them with the entanglement features of helium-like systems. We compute the amount of entanglement associated with the wavefunctions corresponding to the fundamental and first few excited states of these models. We investigate the dependence of the entanglement on the parameters of the models and on the quantum numbers of the eigenstates. It is found that the amount of entanglement of the system tends to increase with energy in both models. In addition, we study the entanglement of a few states of helium-like systems, which we compute using high-quality Kinoshita-like eigenfunctions. The dependence of the entanglement of helium-like atoms on the nuclear charge and on energy is found to be consistent with the trends observed in the previous two model systems.

  19. Putting structure into context: fitting of atomic models into electron microscopic and electron tomographic reconstructions.

    Science.gov (United States)

    Volkmann, Niels

    2012-02-01

    A complete understanding of complex dynamic cellular processes such as cell migration or cell adhesion requires the integration of atomic level structural information into the larger cellular context. While direct atomic-level information at the cellular level remains inaccessible, electron microscopy, electron tomography and their associated computational image processing approaches have now matured to a point where sub-cellular structures can be imaged in three dimensions at the nanometer scale. Atomic-resolution information obtained by other means can be combined with this data to obtain three-dimensional models of large macromolecular assemblies in their cellular context. This article summarizes some recent advances in this field. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. 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

  1. 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.

  2. 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...

  3. 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.

  4. Osteoprotective effect of Monascus-fermented dioscorea in ovariectomized rat model of postmenopausal osteoporosis.

    Science.gov (United States)

    Chiang, Shen-Shih; Chang, Shang-Ping; Pan, Tzu-Ming

    2011-09-14

    This experiment established the ovariectomized (OVX) rat model of postmenopausal osteoporosis and examined the effect of the oral administration of different dosages of dioscorea, red mold dioscorea (RMD), and soy isoflavones on bone mineral density (BMD). Three months after osteoporosis had been induced and 4 weeks after feeding had begun, the tibia and femur BMD of OVX rats administered RMD showed significant increases compared with that of all other groups of OVX rats. Closer examination using microcomputed tomography also revealed that the RMD-administered rats had denser trabecular bone volume and a higher trabecular number compared to all other rat groups. Reconstructed 3D imaging indicated increases in cancellous bone mineral content, cancellous bone mineral density, and cortical bone mineral content of the proximal tibia in OVX rats. These findings indicate that administration of monacolin K and phytoestrogen diosgenin could prevent bone loss induced by estrogen deficiency.

  5. 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...

  6. Sodium salicylate reduced insulin resistance in the retina of a type 2 diabetic rat model.

    Science.gov (United States)

    Jiang, Youde; Thakran, Shalini; Bheemreddy, Rajini; Coppess, William; Walker, Robert J; Steinle, Jena J

    2015-01-01

    Sodium salicylate has been reported to reduce markers of diabetic retinopathy in a type 1 rat model. Because rates of type 2 diabetes are on the rise, we wanted to determine whether salicylate could improve insulin resistance in a type 2 rat model, as well as improve retinal function. We treated lean and obese BBZDR/Wor type 2 diabetic rats with salicylate in their chow for 2 months. Prior to salicylate treatment, rats underwent an electroretinogram to measure retinal function. After 2 months of treatment, rats underwent an additional electroretinogram prior to sacrifice. In addition to the animal model, we also treated retinal endothelial cells (REC) and rat Müller cells with salicylate and performed the same analyses as done for the rat retinal lysates. To investigate the role of salicylate in insulin signaling, we measured TNFα and caspase 3 levels by ELISA, as well as performed Western blotting for insulin receptor substrate 1, insulin receptor, SOCS3, and pro- and anti-apoptotic markers. Data demonstrated that salicylate significantly improved retinal function, as well as reduced TNFα and SOCS3-induced insulin resistance in all samples. Overall, results suggest that salicylate is effective in reducing insulin resistance in the retina of type 2 diabetic rat models.

  7. Sodium Salicylate Reduced Insulin Resistance in the Retina of a Type 2 Diabetic Rat Model

    Science.gov (United States)

    Jiang, Youde; Thakran, Shalini; Bheemreddy, Rajini; Coppess, William; Walker, Robert J.; Steinle, Jena J.

    2015-01-01

    Sodium salicylate has been reported to reduce markers of diabetic retinopathy in a type 1 rat model. Because rates of type 2 diabetes are on the rise, we wanted to determine whether salicylate could improve insulin resistance in a type 2 rat model, as well as improve retinal function. We treated lean and obese BBZDR/Wor type 2 diabetic rats with salicylate in their chow for 2 months. Prior to salicylate treatment, rats underwent an electroretinogram to measure retinal function. After 2 months of treatment, rats underwent an additional electroretinogram prior to sacrifice. In addition to the animal model, we also treated retinal endothelial cells (REC) and rat Müller cells with salicylate and performed the same analyses as done for the rat retinal lysates. To investigate the role of salicylate in insulin signaling, we measured TNFα and caspase 3 levels by ELISA, as well as performed Western blotting for insulin receptor substrate 1, insulin receptor, SOCS3, and pro- and anti-apoptotic markers. Data demonstrated that salicylate significantly improved retinal function, as well as reduced TNFα and SOCS3-induced insulin resistance in all samples. Overall, results suggest that salicylate is effective in reducing insulin resistance in the retina of type 2 diabetic rat models. PMID:25874611

  8. Fenugreek Prevents the Development of STZ-Induced Diabetic Nephropathy in a Rat Model of Diabetes

    Directory of Open Access Journals (Sweden)

    Yingli Jin

    2014-01-01

    evidently reduced by fenugreek treatment. Furthermore, the upregulation of TGF-β1 and CTGF at a transcriptional and translational level in DN rats was distinctly inhibited by fenugreek. Consequently, fenugreek prevents DN development in a STZ-induced diabetic rat model.

  9. Basement membrane chondroitin sulfate proteoglycan alterations in a rat model of polycystic kidney disease

    DEFF Research Database (Denmark)

    Ehara, T; Carone, F A; McCarthy, K J

    1994-01-01

    Alterations in basement membrane components, notably proteoglycans, in a rat model of polycystic kidney disease have been investigated. Rats were fed phenol II (2-amino-4-hydroxyphenyl-5-phenyl thiazole) for 4 days and then changed to normal diet for a 7-day recovery period. Marked dilation of di...

  10. Evaluation of novel resorbable membranes for bone augmentation in a rat model

    NARCIS (Netherlands)

    Zeng, N.; van Leeuwen, A.C.; Yuan, Huipin; Bos, R.R.M.; Grijpma, Dirk W.; Kuijer, R.

    2016-01-01

    Objectives Our study compared two novel, biodegradable poly(trimethylene carbonate) (PTMC) barrier membranes to clinically applied barrier membranes in maintaining volume of block autologous bone grafts in a rat mandible model. Material and methods Two hundred and forty rats were included in this

  11. Evaluation of novel resorbable membranes for bone augmentation in a rat model

    NARCIS (Netherlands)

    Zeng, Ni; van Leeuwen, Anne; Yuan, Huipin; Bos, Ruud R M; Grijpma, Dirk W; Kuijer, Roelof

    ObjectivesOur study compared two novel, biodegradable poly(trimethylene carbonate) (PTMC) barrier membranes to clinically applied barrier membranes in maintaining volume of block autologous bone grafts in a rat mandible model. Material and methodsTwo hundred and forty rats were included in this

  12. Effects of oral adsorbent in the rat model of chronic renal failure.

    Science.gov (United States)

    Yoshida, Y; Sakai, T; Ise, M

    1992-01-01

    The effects of oral adsorbent, AST-120 (Kureha Chemical Ind. Co., Tokyo), were studied in the rat model of subtotal nephrectomy. In 34 female Sprague-Dawley rats, three quarters of the renal mass were removed from the left kidney by ligation of 3 branches of the left renal artery. One week later, the right kidney was removed. Two days after right nephrectomy, control rats were fed standard rat chow ad libitum, while AST-120-treated rats were fed standard rat chow containing AST-120 ad libitum. The animals were observed for 9 weeks. Of the control rats, some became severely ill and appeared to be almost dying before 9 weeks, while paired AST-120-treated rats appeared well. Body weight was maintained better in AST-120-treated rats than in control rats. At completion of the study, levels of BUN and serum creatinine were lower and glomerular filtration rate and renal plasma flow rate were higher in AST-120-treated than in control rats (p < 0.05), although there was no statistically significant difference in proteinuria. Serum uremic peak 2a measured by high-performance liquid chromatography, which is considered to correspond to uremic toxins, was statistically lower in AST-120-treated rats (p < 0.05). Finally, a marked reduction in the degree of glomerular sclerosis was noted in AST-120-treated versus control rats (p < 0.05). The results indicate that AST-120 is effective in the treatment of chronic renal failure in terms of reducing uremic symptoms as well as preserving renal function and glomerular architecture. The data also indicate that a reduction in uremic toxins could delay the progressive damage of renal function and glomerular architecture in chronic renal failure.

  13. 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.

  14. 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

  15. Computational electronics semiclassical and quantum device modeling and simulation

    CERN Document Server

    Vasileska, Dragica; Klimeck, Gerhard

    2010-01-01

    Starting with the simplest semiclassical approaches and ending with the description of complex fully quantum-mechanical methods for quantum transport analysis of state-of-the-art devices, Computational Electronics: Semiclassical and Quantum Device Modeling and Simulation provides a comprehensive overview of the essential techniques and methods for effectively analyzing transport in semiconductor devices. With the transistor reaching its limits and new device designs and paradigms of operation being explored, this timely resource delivers the simulation methods needed to properly model state-of

  16. 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.

  17. The Empowerment of Plasma Modeling by Fundamental Electron Scattering Data

    Science.gov (United States)

    Kushner, Mark J.

    2015-09-01

    Modeling of low temperature plasmas addresses at least 3 goals - investigation of fundamental processes, analysis and optimization of current technologies, and prediction of performance of as yet unbuilt systems for new applications. The former modeling may be performed on somewhat idealized systems in simple gases, while the latter will likely address geometrically and electromagnetically intricate systems with complex gas mixtures, and now gases in contact with liquids. The variety of fundamental electron and ion scattering data (FSD) required for these activities increases from the former to the latter, while the accuracy required of that data probably decreases. In each case, the fidelity, depth and impact of the modeling depends on the availability of FSD. Modeling is, in fact, empowered by the availability and robustness of FSD. In this talk, examples of the impact of and requirements for FSD in plasma modeling will be discussed from each of these three perspectives using results from multidimensional and global models. The fundamental studies will focus on modeling of inductively coupled plasmas sustained in Ar/Cl2 where the electron scattering from feed gases and their fragments ultimately determine gas temperatures. Examples of the optimization of current technologies will focus on modeling of remote plasma etching of Si and Si3N4 in Ar/NF3/N2/O2 mixtures. Modeling of systems as yet unbuilt will address the interaction of atmospheric pressure plasmas with liquids Work was supported by the US Dept. of Energy (DE-SC0001939), National Science Foundation (CHE-124752), and the Semiconductor Research Corp.

  18. Neurophysiological modeling of bladder afferent activity in the rat overactive bladder model.

    Science.gov (United States)

    Choudhary, Mahipal; van Asselt, Els; van Mastrigt, Ron; Clavica, Francesco

    2015-07-01

    The overactive bladder (OAB) is a syndrome-based urinary dysfunction characterized by "urgency, with or without urge incontinence, usually with frequency and nocturia". Earlier we developed a mathematical model of bladder nerve activity during voiding in anesthetized rats and found that the nerve activity in the relaxation phase of voiding contractions was all afferent. In the present study, we applied this mathematical model to an acetic acid (AA) rat model of bladder overactivity to study the sensitivity of afferent fibers in intact nerves to bladder pressure and volume changes. The afferent activity in the filling phase and the slope, i.e., the sensitivity of the afferent fibers to pressure changes in the post-void relaxation phase, were found to be significantly higher in AA than in saline measurements, while the offset (nerve activity at pressure ~0) and maximum pressure were comparable. We have thus shown, for the first time, that the sensitivity of afferent fibers in the OAB can be studied without cutting nerves or preparation of single fibers. We conclude that bladder overactivity induced by AA in rats is neurogenic in origin and is caused by increased sensitivity of afferent sensors in the bladder wall.

  19. Use of scanning electron microscopy to confirm the identity of tropical rat mite (Ornithonyssus bacoti): the cause of rat mite dermatitis.

    Science.gov (United States)

    Nath, Anjan Jyoti; Islam, Saidul; Sahu, Samyak

    2016-03-01

    Cutaneous lesions in human patient due to the bite of rat mite Ornithonyssus bacoti are frequently misdiagnosed as allergies, fungal infection, or bacterial infection. Bite lesions in the personnel working in a Laboratory Animal facility which was infested with O. bacoti is reported here along with its therapeutic management. Diagnosis of the parasites obtained from the clothing of the personnel and later from the infested mice colony was based on preliminary light microscopy and confirmed by scanning electron microscopy. The mean length and breadth of adult female mite were 1.13 mm × 0.63 mm. The body is hairy, unsegmented and has four pairs of legs. The gnathostoma has long pointed chelicerae and pedipalp. The dorsal surface has one dorsal shield, and the ventral surface has three shields- sternal, genital and anal shield. Treatment of dermatitis involved antihistaminic drugs for a period of 3-5 days. The skin lesion, characterized by papular erythema, tends to disappear within a period of 4-5 days of antihistaminic treatment. In untreated cases, the lesions disappeared within 7-10 days. Tropical rat mite O. bacoti Hirst, 1931 was identified to be the cause of infestation in the laboratory mice colony of Pasteur Institute of India, Coonoor, Tamil Nadu, predisposing the animal handlers to be temporary host.

  20. A Novel Model of Intravital Platelet Imaging Using CD41-ZsGreen1 Transgenic Rats.

    Directory of Open Access Journals (Sweden)

    Makoto Mizuno

    Full Text Available Platelets play pivotal roles in both hemostasis and thrombosis. Although models of intravital platelet imaging are available for thrombosis studies in mice, few are available for rat studies. The present effort aimed to generate fluorescent platelets in rats and assess their dynamics in a rat model of arterial injury. We generated CD41-ZsGreen1 transgenic rats, in which green fluorescence protein ZsGreen1 was expressed specifically in megakaryocytes and thus platelets. The transgenic rats exhibited normal hematological and biochemical values with the exception of body weight and erythroid parameters, which were slightly lower than those of wild-type rats. Platelet aggregation, induced by 20 μM ADP and 10 μg/ml collagen, and blood clotting times were not significantly different between transgenic and wild-type rats. Saphenous arteries of transgenic rats were injured with 10% FeCl3, and the formation of fluorescent thrombi was evaluated using confocal microscopy. FeCl3 caused time-dependent increases in the mean fluorescence intensity of injured arteries of vehicle-treated rats. Prasugrel (3 mg/kg, p.o., administered 2 h before FeCl3, significantly inhibited fluorescence compared with vehicle-treated rats (4.5 ± 0.4 vs. 14.9 ± 2.4 arbitrary fluorescence units at 30 min, respectively, n = 8, P = 0.0037. These data indicate that CD41-ZsGreen1 transgenic rats represent a useful model for intravital imaging of platelet-mediated thrombus formation and the evaluation of antithrombotic agents.

  1. 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

  2. Combination antioxidant effect of α-tocoferol and erdosteine in ischemia-reperfusion injury in rat model.

    Science.gov (United States)

    Yurdakul, Talat; Kulaksizoglu, Haluk; Pişkin, Mehmet Mesut; Avunduk, Mustafa Cihat; Ertemli, Esra; Gokçe, Gürhan; Barişkaner, Hülagü; Byükbaş, Sadik; Kocabas, Volkan

    2010-09-01

    Renal ischemia/reperfusion (I/R) which is an important cause of renal dysfunction is inevitable in renal transplantation, surgical revascularization of the renal artery, partial nephrectomy and treatment of suprarenal aortic aneurysms. The purpose of this study was to investigate the efficacy of α-tocopherol and erdosteine combination in the reduction in injury induced by ROS in a rat model of renal ischemia-reperfusion. Thirty-six- male Wistar albino rats weighing 200-250 g were utilized for this study. Rats were divided into six groups, and each group was consistent of six rats: (1) sham-operated (control), (2) ischemia group (3) I/R group, (4) I/R/α-tocoferol group (5) I/erdosteine group (6). I/R/α-tocoferol and erdosteine group. Biochemically tissue MDA, XO and SOD activities, light and electron microscopic findings were evaluated. The erdosteine and α-tocoferol significantly reversed the effect of protein oxidation and lipid peroxidation induced by I/R shown by the decreased levels of MDA and XO activities. Both MDA and XO levels were found to be lower in group 6 compared to single agent treatment groups, and this was significantly different. All treatment groups showed increased SOD activity, which accounts for their oxidative properties. The mean Paller score of the combination treatment group (group 6) was lower than all groups except the sham group (3.67 ± 1.2), and this finding was statistically significant (0.05). Our results showed that the antioxidant pretreatment with α-tocopherol and erdosteine combination reduced lipid peroxidation of renal cellular membranes in a model of normothermic renal ischemia-reperfusion in rats. Combination of erdosteine and α-tocopherol has a synergistic effect of protection against oxidative processes. Long-term use of α-tocopherol seems to have a greater effect on the prevention of IR injury. However, further investigations are needed for the clinical applications of our findings.

  3. Functional gait analysis in a spinal contusion rat model.

    Science.gov (United States)

    Bhimani, Abhiraj D; Kheirkhah, Pouyan; Arnone, Gregory D; Nahhas, Cindy R; Kumar, Prateek; Wonais, Matt; Hidrogo, Hugo; Aguilar, Eddy; Spalinski, Daniel; Gopalka, Mahie; Roth, Steven; Mehta, Ankit I

    2017-12-01

    Evaluating functional performance of spinal cord injury (SCI) rat models is essential for the development of novel treatments and breakthroughs. However, due to the variety of functional analysis methods available - each with its own strengths and weaknesses - it can be challenging to choose the most appropriate functional analysis test for the animal model. Therefore, we analyzed the strengths and weaknesses of five methods in order to determine which test is not only accurate and easily reproducible, but also relatively inexpensive so that it can be adopted universally. When comparing the Basso, Beattie, and Bresnahan (BBB) test, Ladder walking test, CatWalk test, Rotating Rod test, Microsoft Kinect system and VICON, we used the criteria of sensitivity, quality of data generated, statistical analysis of data, and rate of human error. These specific tests were chosen in order to compare the advantages and disadvantages of simple yet effective methods (BBB, Ladder test, and Rotating Rod test) to more complex and computerized methods (Catwalk, Microsoft Kinect and VICON). Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. 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

  5. Modeling Radiation Belt Electron Dynamics with the DREAM3D Diffusion Model

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Weichao [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cunningham, Gregory S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chen, Yue [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Henderson, Michael G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Morley, Steven K. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reeves, Geoffrey D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Blake, Bernard J. [The Aerospace Corporation, El Segundo, CA (United States); Baker, Daniel N. [Lab. for Atmospheric and Space Physics, Boulder, CO (United States); Spence, Harlan [Univ. of New Hampshire, Durham, NH (United States)

    2014-02-14

    The simulation results from our 3D diffusion model on the CRRES era suggest; our model captures the general variations of radiation belt electrons, including the dropouts and the enhancements; the overestimations inside the plasmapause can be improved by increasing the PA diffusion from hiss waves; and that better DLL and wave models are required.

  6. 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...

  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. 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.

  9. 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.

  10. 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.

  11. Effect of Antihypertensive Drug Treatment on Oxidative Stress Markers in Heart of Spontaneously Hypertensive Rat Models.

    Science.gov (United States)

    Yusoff, Nik Syamimi Nik; Mustapha, Zulkarnain; Sharif, Sharifah Emilia Tuan; Govindasamy, Chandran; Sirajudeen, Kuttulebbai Nainamohamed Salam

    2017-01-01

    Oxidative stress has been suggested to play a role in hypertension- and hypertension-induced organ damage. The effect of antihypertensive drug treatments on oxidative stress markers has not been well assessed. Therefore, in this study we investigated the effect of enalapril on oxidative stress markers in hearts of hypertensive rat models such as spontaneously hypertensive rats (SHR) and SHRs administered N-nitro-L-arginine methyl ester (SHR+L-NAME rats). Male rats were divided into four groups: SHRs, SHR+enalapril (SHR-E) rats, SHR+L-NAME rats, SHR+enalapril+L-NAME (SHRE+L-NAME) rats. Rats (SHREs) were administered enalapril (30 mg kg-1 day-1) in drinking water from week 4 to week 28 and L-NAME (25 mg kg-1 day-1) from week 16 to week 28 in drinking water. At the end of 28 weeks, animals were sacrificed, and their hearts were collected for the assessment of oxidative stress markers and histological examination. Enalapril treatment significantly enhanced the total antioxidant status (TAS) (P heart. The fibrosis areas in SHRs and SHR+L-NAME rats were also markedly reduced. These findings suggest that enalapril might play a protective role in hypertension- and hypertension-induced organ damage.

  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. The rat: a laboratory model for studies of the diving response

    Science.gov (United States)

    Gan, Qi; Juric, Rajko

    2010-01-01

    Underwater submersion in mammals induces apnea, parasympathetically mediated bradycardia, and sympathetically mediated peripheral vasoconstriction. These effects are collectively termed the diving response, potentially the most powerful autonomic reflex known. Although these physiological responses are directed by neurons in the brain, study of neural control of the diving response has been hampered since 1) it is difficult to study the brains of animals while they are underwater, 2) feral marine mammals are usually large and have brains of variable size, and 3) there are but few references on the brains of naturally diving species. Similar responses are elicited in anesthetized rodents after stimulation of their nasal mucosa, but this nasopharyngeal reflex has not been compared directly with natural diving behavior in the rat. In the present study, we compared hemodynamic responses elicited in awake rats during volitional underwater submersion with those of rats swimming on the water's surface, rats involuntarily submerged, and rats either anesthetized or decerebrate and stimulated nasally with ammonia vapors. We show that the hemodynamic changes to voluntary diving in the rat are similar to those of naturally diving marine mammals. We also show that the responses of voluntary diving rats are 1) significantly different from those seen during swimming, 2) generally similar to those elicited in trained rats involuntarily “dunked” underwater, and 3) generally different from those seen from dunking naive rats underwater. Nasal stimulation of anesthetized rats differed most from the hemodynamic variables of rats trained to dive voluntarily. We propose that the rat trained to dive underwater is an excellent laboratory model to study neural control of the mammalian diving response, and also suggest that some investigations may be done with nasal stimulation of decerebrate preparations to decipher such control. PMID:20093670

  14. Young Sprague Dawley rats infected by Plasmodium berghei: A relevant experimental model to study cerebral malaria.

    Directory of Open Access Journals (Sweden)

    Sokhna Keita Alassane

    Full Text Available Cerebral malaria (CM is the most severe manifestation of human malaria yet is still poorly understood. Mouse models have been developed to address the subject. However, their relevance to mimic human pathogenesis is largely debated. Here we study an alternative cerebral malaria model with an experimental Plasmodium berghei Keyberg 173 (K173 infection in Sprague Dawley rats. As in Human, not all infected subjects showed cerebral malaria, with 45% of the rats exhibiting Experimental Cerebral Malaria (ECM symptoms while the majority (55% of the remaining rats developed severe anemia and hyperparasitemia (NoECM. These results allow, within the same population, a comparison of the noxious effects of the infection between ECM and severe malaria without ECM. Among the ECM rats, 77.8% died between day 5 and day 12 post-infection, while the remaining rats were spontaneously cured of neurological signs within 24-48 hours. The clinical ECM signs observed were paresis quickly evolving to limb paralysis, global paralysis associated with respiratory distress, and coma. The red blood cell (RBC count remained normal but a drastic decrease of platelet count and an increase of white blood cell numbers were noted. ECM rats also showed a decrease of glucose and total CO2 levels and an increase of creatinine levels compared to control rats or rats with no ECM. Assessment of the blood-brain barrier revealed loss of integrity, and interestingly histopathological analysis highlighted cyto-adherence and sequestration of infected RBCs in brain vessels from ECM rats only. Overall, this ECM rat model showed numerous clinical and histopathological features similar to Human CM and appears to be a promising model to achieve further understanding the CM pathophysiology in Humans and to evaluate the activity of specific antimalarial drugs in avoiding/limiting cerebral damages from malaria.

  15. Modeling radiation belt electron dynamics during GEM challenge intervals with the DREAM3D diffusion model

    Science.gov (United States)

    Tu, Weichao; Cunningham, G. S.; Chen, Y.; Henderson, M. G.; Camporeale, E.; Reeves, G. D.

    2013-10-01

    a response to the Geospace Environment Modeling (GEM) "Global Radiation Belt Modeling Challenge," a 3D diffusion model is used to simulate the radiation belt electron dynamics during two intervals of the Combined Release and Radiation Effects Satellite (CRRES) mission, 15 August to 15 October 1990 and 1 February to 31 July 1991. The 3D diffusion model, developed as part of the Dynamic Radiation Environment Assimilation Model (DREAM) project, includes radial, pitch angle, and momentum diffusion and mixed pitch angle-momentum diffusion, which are driven by dynamic wave databases from the statistical CRRES wave data, including plasmaspheric hiss, lower-band, and upper-band chorus. By comparing the DREAM3D model outputs to the CRRES electron phase space density (PSD) data, we find that, with a data-driven boundary condition at Lmax = 5.5, the electron enhancements can generally be explained by radial diffusion, though additional local heating from chorus waves is required. Because the PSD reductions are included in the boundary condition at Lmax = 5.5, our model captures the fast electron dropouts over a large L range, producing better model performance compared to previous published results. Plasmaspheric hiss produces electron losses inside the plasmasphere, but the model still sometimes overestimates the PSD there. Test simulations using reduced radial diffusion coefficients or increased pitch angle diffusion coefficients inside the plasmasphere suggest that better wave models and more realistic radial diffusion coefficients, both inside and outside the plasmasphere, are needed to improve the model performance. Statistically, the results show that, with the data-driven outer boundary condition, including radial diffusion and plasmaspheric hiss is sufficient to model the electrons during geomagnetically quiet times, but to best capture the radiation belt variations during active times, pitch angle and momentum diffusion from chorus waves are required.

  16. 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

  17. 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)

  18. Modelling of electron transport and of sawtooth activity in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    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

  19. 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.

  20. 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.

  1. Degraded neural and behavioral processing of speech sounds in a rat model of Rett syndrome.

    Science.gov (United States)

    Engineer, Crystal T; Rahebi, Kimiya C; Borland, Michael S; Buell, Elizabeth P; Centanni, Tracy M; Fink, Melyssa K; Im, Kwok W; Wilson, Linda G; Kilgard, Michael P

    2015-11-01

    Individuals with Rett syndrome have greatly impaired speech and language abilities. Auditory brainstem responses to sounds are normal, but cortical responses are highly abnormal. In this study, we used the novel rat Mecp2 knockout model of Rett syndrome to document the neural and behavioral processing of speech sounds. We hypothesized that both speech discrimination ability and the neural response to speech sounds would be impaired in Mecp2 rats. We expected that extensive speech training would improve speech discrimination ability and the cortical response to speech sounds. Our results reveal that speech responses across all four auditory cortex fields of Mecp2 rats were hyperexcitable, responded slower, and were less able to follow rapidly presented sounds. While Mecp2 rats could accurately perform consonant and vowel discrimination tasks in quiet, they were significantly impaired at speech sound discrimination in background noise. Extensive speech training improved discrimination ability. Training shifted cortical responses in both Mecp2 and control rats to favor the onset of speech sounds. While training increased the response to low frequency sounds in control rats, the opposite occurred in Mecp2 rats. Although neural coding and plasticity are abnormal in the rat model of Rett syndrome, extensive therapy appears to be effective. These findings may help to explain some aspects of communication deficits in Rett syndrome and suggest that extensive rehabilitation therapy might prove beneficial. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Assessment of pharmacokinetic interaction of spirulina with glitazone in a type 2 diabetes rat model.

    Science.gov (United States)

    Gupta, Annu; Nair, Anroop; Kumria, Rachna; Al-Dhubiab, Bandar-E; Chattopadhyaya, Ipshita; Gupta, Sumeet

    2013-12-01

    The objective of the current study was to assess the possible pharmacokinetic interactions of spirulina with glitazones in an insulin resistance rat model. Wistar male albino rats were equally divided into five groups: insulin resistant rats+spirulina (500 mg/kg)+pioglitazone (10 mg/kg), insulin resistant rats+pioglitazone (10 mg/kg), insulin resistant rats+spirulina (500 mg/kg)+rosiglitazone (10 mg/kg), insulin resistant rats+rosiglitazone (10 mg/kg), and insulin resistant rats+spirulina (500 mg/kg). Described doses of pioglitazone, rosiglitazone, or spirulina were per orally administered and the plasma drug concentrations were determined. The pharmacokinetic parameters such as Tmax, Cmax, AUC(0-α), t1/2, and Kel were determined by plotting the drug concentration as a function of time. The data observed in this acute study indicated that there was no statistically significant difference in any of the pharmacokinetic parameters (Tmax, Cmax, AUC(0-α), t1/2, and Kel) of glitazones (pioglitazone, rosiglitazone) or spirulina, when they were coadministered. Given the promising results, this study concludes that the coadministration of spirulina does not influence the pharmacokinetics of glitazones in a type 2 diabetes rat model. Further chronic in vivo studies are recommended to assess the real time effect.

  3. Diet-induced metabolic syndrome model in rats

    Directory of Open Access Journals (Sweden)

    Reza Homayounfar

    2013-03-01

    Full Text Available Background & Objective: Risk for heart disease, diabetes, and stroke increases with the number of the metabolic risk factors. In general, a person who has the metabolic syndrome is twice as likely to develop heart disease and five times as likely to develop diabetes as someone who does not have the metabolic syndrome. High-calorie-diet rodent models have contributed significantly to the analysis of the pathophysiology of the metabolic syndrome, but their phenotype varies distinctly between different studies and maybe is not very similar to a model of the metabolic syndrome in humans. We sought to create a model in this study close to the disease in humans.   Materials & Methods: Twenty male, Wistar rats were randomly assigned to the high-calorie diet group with 416 calories per 100 grams (researcher made or the control diet group for 12 weeks. Weight changes, lipid profile, glucose, insulin levels, and QUICKI index (an indicator of insulin sensitivity were measured. Weight changes were compared using the repeated measures and the independent t-test, and serum factors were compared using the independent t-test.   Results: There was a significant change in weight, glucose, insulin, and lipid profile except for HDL at the end of the study. The QUICKI index (0.34 ± 0.02 vs. 0.40 ± 0.01; p value <0.0001 suggested that insulin resistance had been created in the high-calorie diet group.   Conclusion: The present study demonstrates the ability to make diet-induced metabolic syndrome domestically.

  4. 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.

  5. Pulmonary Transcriptional Response to Ozone in Healthy and Cardiovascular Compromised Rat Models

    Science.gov (United States)

    The genetic cardiovascular disease (CVD) and associated metabolic impairments can influence the lung injury from inhaled pollutants. We hypothesized that comparative assessment of global pulmonary expression profile of healthy and CVD-prone rat models will provide mechanistic ins...

  6. Suitability of the rat subdermal model for tissue engineering of heart valves.

    Science.gov (United States)

    Christ, Torsten; Dohmen, Pascal M; Holinski, Sebastian; Schönau, Melanie; Heinze, Georg; Konertz, Wolfgang

    2014-12-10

    Tissue engineering (TE) is a promising approach to overcome problems associated with biological heart valve prosthesis. Currently several animal models are used to advance this method. The rat subdermal model is uncomplicated and widely used, but its suitability for TE has not yet been shown. Using the rat subdermal model we implanted two decellularized porcine aortic wall specimens (of which one was endothelialized) and one native porcine aortic wall specimen in 30 Lewis rats, respectively. Endothelial cells (EC) were harvested from the rat jugular veins. After explantation Hematoxylin/Eosin-staining, CD-68-positive cell staining, fibroblast-staining and Von-Willebrand factor staining were performed. All animals survived without complications. Endothelialization was confirmed to be effective by Giemsa staining. Histological evaluation of specimens in Hematoxylin/Eosin staining showed significant decrease (pbiological compatibility, but further questions must be researched using other models.

  7. Evaluating resveratrol as a therapeutic bone agent: preclinical evidence from rat models of osteoporosis.

    Science.gov (United States)

    Tou, Janet C

    2015-08-01

    Resveratrol (RSV) is a naturally occurring plant polyphenol that has potential to attenuate osteoporosis with distinct pathologies. This review evaluates preclinical evidence regarding the efficacy and safety of RSV as a therapeutic bone agent using different rat models. Limitations of these animal models are discussed, and suggestions for strengthening the experimental design of future studies are provided. The ovariectomized rat model of postmenopausal osteoporosis reported that RSV supplementation attenuated estrogen deficiency-induced bone loss and trabecular structural deterioration. RSV safety was indicated by the absence of stimulation of estrogen-sensitive tissue. Providing RSV to rats aged >6 months attenuated age-related bone mass loss and structural deterioration but produced inconsistent effects on bones in rats aged osteoporosis reported that RSV attenuated bone loss in old rats, but higher doses and longer duration supplementation before mechanical loading were required for younger rats. Limitations common to studies using rat models of osteoporosis include requirements to include animals that are skeletally mature, longer study durations, and to adjust for potential confounding effects due to altered body weight and endocrine function. Strengthening experimental design can contribute to translation of animal results to clinically relevant recommendations for humans. Published 2015. This article is U.S. Government work and is in the public domain in the USA.

  8. Mesozeaxanthin Protects Retina from Oxidative Stress in a Rat Model.

    Science.gov (United States)

    Orhan, Cemal; Akdemir, Fatih; Tuzcu, Mehmet; Sahin, Nurhan; Yilmaz, Ismet; Deshpande, Jayant; Juturu, Vijaya; Sahin, Kazim

    2016-11-01

    Mesozeaxanthin (MZ) is able to protect against chronic and cumulative eye damage and neutralize free radicals produced by oxidative stress. The objective of the present study was to evaluate the protective potential of MZ against retinal oxidative damage and growth and transcription factors of the retina in rats fed with high-fat diet (HFD). Twenty-eight Sprague Dawley rats were randomly divided into the following 4 groups: (1) Control, (2) MZ (100 mg/kg bw/d), (3) HFD (42% of calories as fat), and (4) HFD+MZ (100 mg/kg bw/d) group rats were administered daily as supplement for 12 weeks. Consumption of HFD was associated with hyperglycemia and oxidative stress as reflected by increased serum MDA concentration (P retina of rats fed with HFD had increased levels of vascular endothelial growth factor (VEGF), inducible nitric oxide (iNOS), intercellular adhesion molecule-1 (ICAM-1), and nuclear factor-kappa B (NF-κB) levels and decreased nuclear factor erythroid 2-related factor 2 (Nrf2) and heme-oxygenase 1(HO-1) levels compared to the healthy rat retina (P retina of rats fed (P retina and the ability to modulate oxidative stress of retina in rats fed an HFD by suppressing retinal lipid peroxidation and regulating growth and transcription factors.

  9. Electron/muon specific two Higgs doublet model

    Energy Technology Data Exchange (ETDEWEB)

    Kajiyama, Yuji, E-mail: kajiyama-yuuji@akita-pref.ed.jp [Akita Highschool, Tegata-Nakadai 1, Akita, 010-0851 (Japan); Okada, Hiroshi, E-mail: hokada@kias.re.kr [School of Physics, KIAS, Seoul 130-722 (Korea, Republic of); Yagyu, Kei, E-mail: keiyagyu@ncu.edu.tw [Department of Physics, National Central University, Chungli, 32001, Taiwan, ROC (China)

    2014-10-15

    We discuss two Higgs doublet models with a softly-broken discrete S{sub 3} symmetry, where the mass matrix for charged-leptons is predicted as the diagonal form in the weak eigenbasis of lepton fields. Similarly to an introduction of Z{sub 2} symmetry, the tree level flavor changing neutral current can be forbidden by imposing the S{sub 3} symmetry to the model. Under the S{sub 3} symmetry, there are four types of Yukawa interactions depending on the S{sub 3} charge assignment to right-handed fermions. We find that extra Higgs bosons can be muon and electron specific in one of four types of the Yukawa interaction. This property does not appear in any other two Higgs doublet models with a softly-broken Z{sub 2} symmetry. We discuss the phenomenology of the muon and electron specific Higgs bosons at the Large Hadron Collider; namely we evaluate allowed parameter regions from the current Higgs boson search data and discovery potential of such a Higgs boson at the 14 TeV run.

  10. The role of intestinal endotoxemia in a rat model of aluminum neurotoxicity

    OpenAIRE

    Wang, Feng; Guo, Rui-Xia; Li, Wen-Xing; Yu, Bao-Feng; Han, Bai; Liu, Li-Xin; Han, De-Wu

    2017-01-01

    The present study aimed to investigate the effects of intestinal endotoxemia (IETM) in a rat model of aluminum neurotoxicity established by D-galactose and aluminum trichloride (AlCl3). Adult Wistar rats were administered D-galactose and AlCl3 to create the aluminum neurotoxicity model. The learning and memory abilities of the rats were subsequently observed using a Morris water maze test and the serum levels of lipopolysaccharide (LPS), tumor necrosis factor (TNF)-α, interleukin (IL)-1, diam...

  11. Absence of warm-up during active avoidance learning in a rat model of anxiety vulnerability: Insights from computational modeling

    Directory of Open Access Journals (Sweden)

    Catherine E Myers

    2014-08-01

    Full Text Available Avoidance behaviors, in which a learned response causes omission of an upcoming punisher, are a core feature of many psychiatric disorders. While reinforcement learning (RL models have been widely used to study the development of appetitive behaviors, less attention has been paid to avoidance. Here, we present a RL model of leverpress avoidance learning in Sprague-Dawley (SD rats, and in the inbred Wistar-Kyoto (WKY rat, which has been proposed as a model of anxiety vulnerability. We focus on warm-up, transiently decreased avoidance responding at the start of a testing session, which is shown by SD but not WKY rats. We first show that a RL model can correctly simulate key aspects of acquisition, extinction, and warm-up in SD rats; we then show that WKY behavior can be simulated by altering three model parameters, which respectively govern the tendency to explore new behaviors vs. exploit previously-reinforced ones, the tendency to repeat previous behaviors regardless of reinforcement, and the learning rate for predicting future outcomes. This suggests that several, dissociable mechanisms may contribute independently to strain differences in behavior. The model predicts that, if the standard inter-session interval is shortened from 48 to 24 hours, SD rats (but not WKY will continue to show warm-up; we confirm this prediction in an empirical study with SD and WKY rats. The model further predicts that SD rats will continue to show warm-up with inter-session intervals as short as a few minutes, while WKY rats will not show warm-up, even with inter-session intervals as long as a month. Together, the modeling and empirical data indicate that strain differences in warm-up are qualitative, rather than just the result of differential sensitivity to task variables. Understanding the mechanisms that govern expression of warm-up behavior in avoidance may lead to better understanding of pathological avoidance, and potential pathways to modify these processes.

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

    Directory of Open Access Journals (Sweden)

    Fábio Henrique Silva

    Full Text Available 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.

  13. 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

  14. 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.

  15. The electronic disability record: purpose, parameters, and model use case.

    Science.gov (United States)

    Tulu, Bengisu; Horan, Thomas A

    2009-01-01

    The active engagement of consumers is an important factor in achieving widespread success of health information systems. The disability community represents a major segment of the healthcare arena, with more than 50 million Americans experiencing some form of disability. In keeping with the "consumer-driven" approach to e-health systems, this paper considers the distinctive aspects of electronic and personal health record use by this segment of society. Drawing upon the information shared during two national policy forums on this topic, the authors present the concept of Electronic Disability Records (EDR). The authors outline the purpose and parameters of such records, with specific attention to its ability to organize health and financial data in a manner that can be used to expedite the disability determination process. In doing so, the authors discuss its interaction with Electronic Health Records (EHR) and Personal Health Records (PHR). The authors then draw upon these general parameters to outline a model use case for disability determination and discuss related implications for disability health management. The paper further reports on the subsequent considerations of these and related deliberations by the American Health Information Community (AHIC).

  16. 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.

  17. 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

    and thiocarbohydrazide followed by a continuous dehydration procedure. Three types of cells were identified with the scanning electron microscope: A polygonal and oblong epithelial cell was observed in the largest number throughout the duct, whereas in the juxta-saccular half of the duct two additional types...... of epithelial cells were observed. The scanning electron microscopical observations are compared and discussed with reference to transmission electron microscopical observations of the endolymphatic duct....

  18. 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...

  19. 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

  20. The antioxidative and antilipidemic effects of different molecular weight chitosans in metabolic syndrome model rats.

    Science.gov (United States)

    Anraku, Makoto; Michihara, Akihiro; Yasufuku, Taira; Akasaki, Kenji; Tsuchiya, Daiju; Nishio, Hiroaki; Maruyama, Toru; Otagiri, Masaki; Maezaki, Yuji; Kondo, Yuko; Tomida, Hisao

    2010-01-01

    The effect of high and low molecular weight chitosans (HMC; 1000 kDa, LMC; 30 kDa) on oxidative stress and hypercholesterolemia was investigated using male 6-week-old Wistar Kyoto rats as a normal model (Normal-rats) and spontaneously hypertensive rat/ND mcr-cp (SHP/ND) as a metabolic syndrome model (MS-rats), respectively. In Normal-rats, the ingestion of both chitosans over a 4 week period resulted in a significant decrease in total body weight (BW), glucose (Gl), triglyceride (TG), low density lipoprotein (LDL) and serum creatinine (Cre) levels. The ingestion of both chitosans also resulted in a lowered ratio of oxidized to reduced albumin and an increase in total plasma antioxidant activity. In addition to similar results in Normal-rats, the ingestion of only HMC over a 4 week period resulted in a significant decrease in total cholesterol levels in MS-rats. Further, the ingestion of LMC resulted in a significantly higher antioxidant activity than was observed for HMC in both rat models. In in vitro studies, LMC caused a significantly higher reduction in the levels of two stable radicals, compared to HMC, and the effect was both dose- and time-dependent. The findings also show that LDL showed strong binding in the case of HMC. These results suggest that LMC has a high antioxidant activity as well as antilipidemic effects, while HMC results in a significant reduction in the levels of pro-oxidants such as LDL in the gastrointestinal tract, thereby inhibiting the subsequent development of oxidative stress in the systemic circulation in metabolic model rats.

  1. 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

    The availability of useful animal models reflecting the human obesity syndrome is crucial in the search for novel compounds for the pharmacological treatment of obesity. In the current study, we have performed an extensive characterization of the obesity syndrome in a polygenetic animal model......, 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...... including blood biochemistry and glucose homeostasis was examined at 2, 3, 6, and 9 months of age. Furthermore, in 6-month-old HE-fed DIO rats, the anti-obesity effects of liraglutide and sibutramine were examined in a 28-day study. Only HE-fed DIO rats developed visceral obesity, hyperleptinemia...

  2. Reliable modeling of the electronic spectra of realistic uranium complexes

    Science.gov (United States)

    Tecmer, Paweł; Govind, Niranjan; Kowalski, Karol; de Jong, Wibe A.; Visscher, Lucas

    2013-07-01

    We present an EOMCCSD (equation of motion coupled cluster with singles and doubles) study of excited states of the small [UO2]2+ and [UO2]+ model systems as well as the larger UVIO2(saldien) complex. In addition, the triples contribution within the EOMCCSDT and CR-EOMCCSD(T) (completely renormalized EOMCCSD with non-iterative triples) approaches for the [UO2]2+ and [UO2]+ systems as well as the active-space variant of the CR-EOMCCSD(T) method—CR-EOMCCSd(t)—for the UVIO2(saldien) molecule are investigated. The coupled cluster data were employed as benchmark to choose the "best" appropriate exchange-correlation functional for subsequent time-dependent density functional (TD-DFT) studies on the transition energies for closed-shell species. Furthermore, the influence of the saldien ligands on the electronic structure and excitation energies of the [UO2]+ molecule is discussed. The electronic excitations as well as their oscillator dipole strengths modeled with TD-DFT approach using the CAM-B3LYP exchange-correlation functional for the [UVO2(saldien)]- with explicit inclusion of two dimethyl sulfoxide molecules are in good agreement with the experimental data of Takao et al. [Inorg. Chem. 49, 2349 (2010), 10.1021/ic902225f].

  3. Eldecalcitol prevents endothelial dysfunction in postmenopausal osteoporosis model rats.

    Science.gov (United States)

    Serizawa, Kenichi; Yogo, Kenji; Tashiro, Yoshihito; Takeda, Satoshi; Kawasaki, Ryohei; Aizawa, Ken; Endo, Koichi

    2016-02-01

    Postmenopausal women have high incidence of cardiovascular events as estrogen deficiency can cause endothelial dysfunction. Vitamin D is reported to be beneficial on endothelial function, but it remains controversial whether vitamin D is effective for endothelial dysfunction under the treatment for osteoporosis in postmenopausal women. The aim of this study was to evaluate the endothelial protective effect of eldecalcitol (ELD) in ovariectomized (OVX) rats. ELD (20  ng/kg) was orally administrated five times a week for 4 weeks from 1 day after surgery. After that, flow-mediated dilation (FMD) as an indicator of endothelial function was measured by high-resolution ultrasound in the femoral artery of living rats. ELD ameliorated the reduction of FMD in OVX rats. ELD inhibited the increase in NOX4, nitrotyrosine, and p65 and the decrease in dimer/monomer ratio of nitric oxide synthase in OVX rat femoral arteries. ELD also prevented the decrease in peroxisome proliferator-activated receptor gamma (PPARγ) in femoral arteries and cultured endothelial cells. Although PPARγ is known to inhibit osteoblastogenesis, ELD understandably increased bone mineral density of OVX rats without increase in PPARγ in bone marrow. These results suggest that ELD prevented the deterioration of endothelial function under condition of preventing bone loss in OVX rats. This endothelial protective effect of ELD might be exerted through improvement of endothelial nitric oxide synthase uncoupling, which is mediated by an antioxidative effect through normalization of vascular PPARγ/NF-κB signaling. © 2016 Society for Endocrinology.

  4. 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

  5. Establishment of a rat model of craniocerebral blast injury induced by cabin explosion

    Directory of Open Access Journals (Sweden)

    Yan-teng LI

    2017-10-01

    Full Text Available Objective To establish a rat model of craniocerebral blast injury caused by the shock wave of cabin explosion. Methods Fifty male adult Sprague–Dawley rats were randomly divided into 5 groups (10 each: 3g, 5g, 8g TNT with vest groups, 5g TNT without vest group and control group. Uncased explosives of different equivalent were suspended in the cabin center. After anesthesia, with exception of control group, the rats were placed in prone position about 31 cm below the explosive, facing the explosive with or without vest. After the explosion, the survived rats were observed, serological and pathological examinations were performed at 3h, 1d and 3d after the explosion. Results In terms of tissue damage and mortality, compared with the control group, no obvious injury formed in rats of the 3g TNT with vest group, and all of them survived; Rats in 5g TNT with vest group showed mild lung injury, brain tissue edema, enlarged blood vessel, patchy hemorrhage on the brain surface, and with a mortality of 30%; Rats in 8g TNT with vest group showed serious organ damage with a mortality of 80%; Rats in 5g TNT without vest group suffered from severe lung injury, almost all died right after the explosion. Therefore, rats in 5g TNT with vest group were more in line with the experimental needs. Further serum and pathologic examinations showed that the brain water content increased, the serum neuron specific enolase (NSE and S-100β protein also increased markedly, and necrotic or apoptotic changes happened in the cortex and hippocampus neurons. Conclusion A stable animal model of craniocerebral blast injury may be established with rats in the case of chest and abdomen protected and then exposed to 5g TNT explosion in cabin. DOI: 10.11855/j.issn.0577-7402.2017.09.13

  6. DDX4-EGFP transgenic rat model for the study of germline development and spermatogenesis.

    Science.gov (United States)

    Gassei, Kathrin; Sheng, Yi; Fayomi, Adetunji; Mital, Payal; Sukhwani, Meena; Lin, Chih-Cheng; Peters, Karen A; Althouse, Andrew; Valli, Hanna; Orwig, Kyle E

    2017-03-01

    Spermatogonial stem cells (SSC) are essential for spermatogenesis and male fertility. In addition, these adult tissue stem cells can be used as vehicles for germline modification in animal models and may have application for treating male infertility. To facilitate the investigation of SSCs and germ lineage development in rats, we generated a DEAD-box helicase 4 (DDX4) (VASA) promoter-enhanced green fluorescent protein (EGFP) reporter transgenic rat. Quantitative real-time polymerase chain reaction and immunofluorescence confirmed that EGFP was expressed in the germ cells of the ovaries and testes and was absent in somatic cells and tissues. Germ cell transplantation demonstrated that the EGFP-positive germ cell population from DDX4-EGFP rat testes contained SSCs capable of establishing spermatogenesis in experimentally infertile mouse recipient testes. EGFP-positive germ cells could be easily isolated by fluorescence-activated cells sorting, while simultaneously removing testicular somatic cells from DDX4-EGFP rat pup testes. The EGFP-positive fraction provided an optimal cell suspension to establish rat SSC cultures that maintained long-term expression of zinc finger and BTB domain containing 16 (ZBTB16) and spalt-like transcription factor 4 (SALL4), two markers of mouse SSCs that are conserved in rats. The novel DDX4-EGFP germ cell reporter rat described here combined with previously described GCS-EGFP rats, rat SSC culture and gene editing tools will improve the utility of the rat model for studying stem cells and germ lineage development. © The Authors 2017. Published by Oxford University Press on behalf of Society for the Study of Reproduction.

  7. 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.

  8. 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)

  9. 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

  10. Naringin prevents bone loss in a rat model of type 1 Diabetes mellitus.

    Science.gov (United States)

    Rivoira, M; Rodríguez, V; Picotto, G; Battaglino, R; Tolosa de Talamoni, N

    2018-01-01

    The aim of this work was to know whether naringin (NA) could prevent the bone complications in a model of streptozotocin (STZ) induced diabetes. Rats were divided in: 1) controls, 2) STZ-rats, 3) STZ-rats treated with 40 mg NA/kg, and 4) STZ-rats treated with 80 mg NA/kg. BMD and BMC were performed by DEXA. Bone histomorphometry and histology as well as TRAP staining were done in tibia. Osteocalcin (OCN) was determined in bone and serum. Glutathione content and SOD and catalase activities were assayed in bone marrow from femur. The data showed that NA80 increased the BMD and BMC from the long bones of STZ-rats. Both NA40 and NA80 normalized the trabecular number and the trabecular separations. An increase in the number of adipocytes and TRAP(+) cells in tibia from STZ-rats was blocked by NA. NA40 treatment increased the number of OCN(+) cells, but only the NA80 treatment allowed to reach the control values. NA normalized the SOD and catalase activities in bone marrow of femur from STZ-rats. In conclusion, NA avoids alterations in the physical properties and microstructure of bone from STZ-rats probably by stimulation of osteoblastogenesis, inhibition of the osteoclastogenesis and adipogenesis via blocking the oxidative stress. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. 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

  12. 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.

  13. Impaired Decision Making and Loss of Inhibitory-Control in a Rat Model of Huntington Disease.

    Science.gov (United States)

    El Massioui, Nicole; Lamirault, Charlotte; Yagüe, Sara; Adjeroud, Najia; Garces, Daniel; Maillard, Alexis; Tallot, Lucille; Yu-Taeger, Libo; Riess, Olaf; Allain, Philippe; Nguyen, Huu Phuc; von Hörsten, Stephan; Doyère, Valérie

    2016-01-01

    Cognitive deficits associated with Huntington disease (HD) are generally dominated by executive function disorders often associated with disinhibition and impulsivity/compulsivity. Few studies have directly examined symptoms and consequences of behavioral disinhibition in HD and its relation with decision-making. To assess the different forms of impulsivity in a transgenic model of HD (tgHD rats), two tasks assessing cognitive/choice impulsivity were used: risky decision-making with a rat gambling task (RGT) and intertemporal choices with a delay discounting task (DD). To assess waiting or action impulsivity the differential reinforcement of low rate of responding task (DRL) was used. In parallel, the volume as well as cellular activity of the amygdala was analyzed. In contrast to WT rats, 15 months old tgHD rats exhibited a poor efficiency in the RGT task with difficulties to choose advantageous options, a steep DD curve as delays increased in the DD task and a high rate of premature and bursts responses in the DRL task. tgHD rats also demonstrated a concomitant and correlated presence of both action and cognitive/choice impulsivity in contrast to wild type (WT) animals. Moreover, a reduced volume associated with an increased basal cellular activity of the central nucleus of amygdala indicated a dysfunctional amygdala in tgHD rats, which could underlie inhibitory dyscontrol. In conclusion, tgHD rats are a good model for impulsivity disorder that could be used more widely to identify potential pharmacotherapies to treat these invasive symptoms in HD.

  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. 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...

  16. 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

  17. 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

    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...... 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...... are compared and discussed with reference to previous transmission electron microscopic studies of the endolymphatic duct....

  18. Modeling skin collimation using the electron pencil beam redefinition algorithm.

    Science.gov (United States)

    Chi, Pai-Chun M; Hogstrom, Kenneth R; Starkschall, George; Antolak, John A; Boyd, Robert A

    2005-11-01

    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 6 x 20-cm2 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 degrees (-45 degrees to +45 degrees), and 10-mm thick lead collimation was placed at +/- 30 degrees. 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

  19. 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...

  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. 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. 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...

  3. Effect of amniotic membrane to reduce postlaminectomy epidural adhesion on a rat model.

    Science.gov (United States)

    Choi, Hyu Jin; Kim, Kyoung Beom; Kwon, Young-Min

    2011-06-01

    Epidural fibrosis and adhesion are the main reasons for post-laminectomy sustained pain and functional disability. In this study, the authors investigate the effect of irradiated freeze-dried human amniotic membrane on reducing epidural adhesion after laminectomy on a rat model. A total of 20 rats were divided into two groups. The group A did not receive human amniotic membrane implantation after laminectomy and group B underwent human amniotic membrane implantation after laminectomy. Gross and microscopic findings were evaluated and compared at postoperative 1, 3 and 8 weeks. The amount of scar tissue and tenacity were reduced grossly in group of rats with human amniotic membrane implantation (group B). On a microscopic evaluation, there were less inflammatory cell infiltration and fibroblast proliferation in group B. This experimental study shows that implantation of irradiated freeze-dried human amniotic membrane reduce epidural fibrosis and adhesion after spinal laminectomy in a rat model.

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

    Directory of Open Access Journals (Sweden)

    Jacob Kjell

    2016-10-01

    Full Text Available 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.

  5. 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

  6. 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.)

  7. 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.

  8. 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.

  9. 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.

  10. Demonstration of 5'-nucleotidase activity in unfixed cryostat sections of rat liver using a combined light- and electron-microscope procedure

    NARCIS (Netherlands)

    Song, J.; Bosch, K. S.; Tigchelaar, W.; van den Munckhof, R. J.; Schellens, J. P.; van Noorden, C. J.; Frederiks, W. M.

    1995-01-01

    In the present study a technique was developed to demonstrate 5'-nucleotidase activity in unfixed cryostat sections of rat liver at the light- and electron-microscope level using a semipermeable membrane. In order to retain the ultrastructure of the unfixed material as much as possible, incubations

  11. 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

  12. Hematological disorders in 6-hydroxydopamine-induced rat model of Parkinson’s disease

    OpenAIRE

    Lucian Hritcu

    2008-01-01

    Objective: The present work was undertaken in order to investigate the effects of right-unilateral lesion of substantia nigra neurons by means of 6- hydroxydopamine (6-OHDA), a dopaminergic-selective neurotoxin, on hematological parameters in rats. The primary reason for the using of rat model of Parkinson’s disease was the interest regarding the role of the central dopaminergic system in hematopoiesis regulation because some neurological diseases like Parkinson’s disease are well-correlated ...

  13. Effect of Vitamin B5 on Liver Enzyme Levels in Bile Duct Ligation Cholestatic Rat Model

    OpenAIRE

    Fatemeh Sadat Emami; Akram Eidi; Pejman Mortazavi; Ahmad Asghari

    2017-01-01

    Background and Objectives: Accumulation of toxic bile salts in a bile duct ligation (BDL) animal model plays a pivotal role in the induction of liver fibrosis. Vitamin B5 is an essential nutrient, which acts as a cofactor in many detoxification system enzymes. In the present research, the antifibrotic effect of vitamin B5 was investigated on liver cholestasis induced by BDL in rats. Methods: In this experimental study, 72 male Wistar rats were divided into 9 groups: Control, sham-operat...

  14. Deep brain stimulation exacerbates hypokinetic dysarthria in a rat model of Parkinson's disease.

    Science.gov (United States)

    King, Nathaniel O; Anderson, Collin J; Dorval, Alan D

    2016-02-01

    Motor symptoms of Parkinson's disease (PD) follow the degeneration of dopaminergic neurons in the substantia nigra pars compacta. Deep brain stimulation (DBS) treats some parkinsonian symptoms, such as tremor, rigidity, and bradykinesia, but may worsen certain medial motor symptoms, including hypokinetic dysarthria. The mechanisms by which DBS exacerbates dysarthria while improving other symptoms are unclear and difficult to study in human patients. This study proposes an animal model of DBS-exacerbated dysarthria. We use the unilateral, 6-hydroxydopamine (6-OHDA) rat model of PD to test the hypothesis that DBS exacerbates quantifiable aspects of vocalization. Mating calls were recorded from sexually experienced male rats under healthy and parkinsonian conditions and during DBS of the subthalamic nucleus. Relative to healthy rats, parkinsonian animals made fewer calls with shorter and less complex vocalizations. In the parkinsonian rats, putatively therapeutic DBS further reduced call frequency, duration, and complexity. The individual utterances of parkinsonian rats spanned a greater bandwidth than those of healthy rats, potentially reducing the effectiveness of the vocal signal. This utterance bandwidth was further increased by DBS. We propose that the parkinsonism-associated changes in call frequency, duration, complexity, and dynamic range combine to constitute a rat analog of parkinsonian dysarthria. Because DBS exacerbates the parkinsonism-associated changes in each of these metrics, the subthalamic stimulated 6-OHDA rat is a good model of DBS-induced hypokinetic dysarthria in PD. This model will help researchers examine how DBS alleviates many motor symptoms of PD while exacerbating parkinsonian speech deficits that can greatly diminish patient quality of life. © 2015 Wiley Periodicals, Inc.

  15. Effect of Ozone on Intestinal Epithelial Homeostasis in a Rat Model

    Directory of Open Access Journals (Sweden)

    Igor Sukhotnik

    2015-01-01

    Full Text Available Background: The positive effects of ozone therapy have been described in many gastrointestinal disorders. The mechanisms of this positive effect of ozone therapy are poorly understood. The purpose of the present study was to investigate whether the use of ozone may potentiate the gut intestinal mucosal homeostasis in a rat model. Methods: Adult rats weighing 250–280 g were randomly assigned to one of three experimental groups of 8 rats each: 1 Control rats were given 2 mL of water by gavage and intraperitoneally (IP for 5 days; 2 O3-PO rats were treated with 2 mL of ozone/oxygen mixture by gavage and 2 mL of water IP for 5 days; 3 O3-IP rats were treated with 2 mL of water by gavage and 2 mL of ozone/oxygen mixture IP for 5 days. Rats were sacrificed on day 6. Bowel and mucosal weight, mucosal DNA and protein, villus height and crypt depth, and cell proliferation and apoptosis were evaluated following sacrifice. Results: The group of O3-IP rats demonstrated a greater jejunal and ileal villus height and crypt depth, a greater enterocyte proliferation index in jejunum, and lower enterocyte apoptosis in ileum compared to control animals. Oral administration of the ozone/oxygen mixture resulted in a less significant effect on cell turnover. Conclusions: Treatment with an ozone/oxygen mixture stimulates intestinal cell turnover in a rat model. Intraperitoneal administration of ozone resulted in a more significant intestinal trophic effect than oral administration.

  16. A comparison of elderly and adult multiple organ dysfunction syndrome in the rat model.

    Science.gov (United States)

    Zhu, Qinglei; Qian, Xiaoshun; Wang, Shiwen; Yin, Tong; Yang, Jie; Xue, Qiao; Xu, Bin

    2006-08-01

    Multiple organ dysfunction syndrome (MODS) in the elderly is the most common cause of mortality in critically ill elderly patients, and it is different from MODS in the adult in clinic. Rare studies have been done on its pathogenesis and the comparison between adult and elderly MODS animal models. This work aimed at exploring the mechanisms mediating elderly MODS and compared this with adult MODS. Male Sprague-Dawley aged and adult rats were intraperitoneally injected with zymosan for incitement of MODS. Aged rats receiving zymosan showed severer pulmonary, cardiac and renal dysfunctions than adult rats. Likewise, the tissue lesions under light microscope in major organs of zymosan treated aged rats were much worse than those of zymosan treated adult rats. Moreover, zymosan treated aged rats showed 142% and 64% greater increase in pulmonary alveolar macrophages (AMs) apoptotic rate and serum TNF-alpha level, respectively, whereas 43% smaller increase in serum IL-10 level compared to zymosan treated adult rats. Furthermore, lung injury was much worse than that in other organs in zymosan treated aged rats. Overall, these results suggest that zymosan can be used in aged rats to incite MODS in the elderly. In the animal model of elderly MODS, there are (1) severer injury in lung, heart and kidney vs adult; (2) easier to develop severe systemic inflammatory response syndrome (SIRS) instead of compensatory anti-inflammatory response syndrome (CARS) compared to the adult; and (3) severer inflammation in lung than other organs indicative of the possible roles of lung in triggering MODS in the elderly.

  17. Hearing impairment in the P23H-1 retinal degeneration rat model

    Directory of Open Access Journals (Sweden)

    Jorge V. Sotoca

    2014-09-01

    Full Text Available The transgenic P23H line 1 (P23H-1 rat expresses a variant of rhodopsin with a mutation that leads to loss of visual function. This rat strain is an experimental model usually employed to study photoreceptor degeneration. Although the mutated protein should not interfere with other sensory functions, observing severe loss of auditory reflexes in response to natural sounds led us to study auditory brain response (ABR recording. Animals were separated into different hearing levels following the response to natural stimuli (hand clapping and kissing sounds. Of all the analyzed animals, 25.9% presented auditory loss before 50 days of age (P50 and 45% were totally deaf by P200. ABR recordings showed that all the rats had a higher hearing threshold than the control Sprague-Dawley (SD rats, which was also higher than any other rat strains. The integrity of the central and peripheral auditory pathway was analyzed by histology and immunocytochemistry. In the cochlear nucleus (CN, statistical differences were found between SD and P23H-1 rats in VGluT1 distribution, but none were found when labeling all the CN synapses with anti-Syntaxin. This finding suggests anatomical and/or molecular abnormalities in the auditory downstream pathway. The inner ear of the hypoacusic P23H-1 rats showed several anatomical defects, including loss and disruption of hair cells and spiral ganglion neurons. All these results can explain, at least in part, how hearing impairment can occur in a high percentage of P23H-1 rats. P23H-1 rats may be considered an experimental model with visual and auditory dysfunctions in future research.

  18. The Dismantling of the Japanese Model in Consumer Electronics

    DEFF Research Database (Denmark)

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

    -based innovation, the current transformation ofsound amplification from conventional to digital amplifiers. We study the early formation of thisnew technology as especially reflected in the particularly dynamic cluster of innovation inDenmark and extend the analysis to the global strategizing around this new......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...

  19. Nonlinear electromagnetic gyrokinetic particle simulations with the electron hybrid model

    Science.gov (United States)

    Nishimura, Y.; Lin, Z.; Chen, L.; Hahm, T.; Wang, W.; Lee, W.

    2006-10-01

    The electromagnetic model with fluid electrons is successfully implemented into the global gyrokinetic code GTC. In the ideal MHD limit, shear Alfven wave oscillation and continuum damping is demonstrated. Nonlinear electromagnetic simulation is further pursued in the presence of finite ηi. Turbulence transport in the AITG unstable β regime is studied. This work is supported by Department of Energy (DOE) Grant DE-FG02-03ER54724, Cooperative Agreement No. DE-FC02-04ER54796 (UCI), DOE Contract No. DE-AC02-76CH03073 (PPPL), and in part by SciDAC Center for Gyrokinetic Particle Simulation of Turbulent Transport in Burning Plasmas. Z. Lin, et al., Science 281, 1835 (1998). F. Zonca and L. Chen, Plasma Phys. Controlled Fusion 30, 2240 (1998); G. Zhao and L. Chen, Phys. Plasmas 9, 861 (2002).

  20. 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...

  1. 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......-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...... 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...

  2. 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.

  3. Finite Element Models for Electron Beam Freeform Fabrication Process

    Science.gov (United States)

    Chandra, Umesh

    2012-01-01

    Electron beam freeform fabrication (EBF3) is a member of an emerging class of direct manufacturing processes known as solid freeform fabrication (SFF); another member of the class is the laser deposition process. Successful application of the EBF3 process requires precise control of a number of process parameters such as the EB power, speed, and metal feed rate in order to ensure thermal management; good fusion between the substrate and the first layer and between successive layers; minimize part distortion and residual stresses; and control the microstructure of the finished product. This is the only effort thus far that has addressed computer simulation of the EBF3 process. The models developed in this effort can assist in reducing the number of trials in the laboratory or on the shop floor while making high-quality parts. With some modifications, their use can be further extended to the simulation of laser, TIG (tungsten inert gas), and other deposition processes. A solid mechanics-based finite element code, ABAQUS, was chosen as the primary engine in developing these models whereas a computational fluid dynamics (CFD) code, Fluent, was used in a support role. Several innovative concepts were developed, some of which are highlighted below. These concepts were implemented in a number of new computer models either in the form of stand-alone programs or as user subroutines for ABAQUS and Fluent codes. A database of thermo-physical, mechanical, fluid, and metallurgical properties of stainless steel 304 was developed. Computing models for Gaussian and raster modes of the electron beam heat input were developed. Also, new schemes were devised to account for the heat sink effect during the deposition process. These innovations, and others, lead to improved models for thermal management and prediction of transient/residual stresses and distortions. Two approaches for the prediction of microstructure were pursued. The first was an empirical approach involving the

  4. Modeling Electronic Skin Response to Normal Distributed Force

    Directory of Open Access Journals (Sweden)

    Lucia Seminara

    2018-02-01

    Full Text Available The reference electronic skin is a sensor array based on PVDF (Polyvinylidene fluoride piezoelectric polymers, coupled to a rigid substrate and covered by an elastomer layer. It is first evaluated how a distributed normal force (Hertzian distribution is transmitted to an extended PVDF sensor through the elastomer layer. A simplified approach based on Boussinesq’s half-space assumption is used to get a qualitative picture and extensive FEM simulations allow determination of the quantitative response for the actual finite elastomer layer. The ultimate use of the present model is to estimate the electrical sensor output from a measure of a basic mechanical action at the skin surface. However this requires that the PVDF piezoelectric coefficient be known a-priori. This was not the case in the present investigation. However, the numerical model has been used to fit experimental data from a real skin prototype and to estimate the sensor piezoelectric coefficient. It turned out that this value depends on the preload and decreases as a result of PVDF aging and fatigue. This framework contains all the fundamental ingredients of a fully predictive model, suggesting a number of future developments potentially useful for skin design and validation of the fabrication technology.

  5. 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

  6. Adipose-Derived Stem Cells Improve Collagenase-Induced Tendinopathy in a Rat Model.

    Science.gov (United States)

    Oshita, Takashi; Tobita, Morikuni; Tajima, Satoshi; Mizuno, Hiroshi

    2016-08-01

    Tendinopathy is a common and highly prevalent musculoskeletal disorder characterized by repetitive activity-related pain and focal tendon tenderness. Histopathologically, tendinopathic tissue mainly shows degenerative changes. Therefore, tendinopathy is not affected by anti-inflammatory therapies. A novel approach, including a stem cell-based therapy, may be beneficial for its treatment. The purpose of this study was to evaluate the effects of adipose-derived stem cells (ASCs) on tendon healing in a rat tendinopathy model. The hypothesis was that ASC transplantation would improve degeneration in collagenase-induced tendinopathy. Controlled laboratory study. Sixteen F344/NSlc rats underwent collagenase injection into the Achilles tendon to induce tendinopathy. At 1 week after collagenase injection, 8 rats received ASCs (ASC group) and 8 received phosphate-buffered saline alone (PBS group). Animals were sacrificed at 4 or 12 weeks after ASC administration, and the degree of degeneration in each tendon was histologically evaluated according to the Bonar scale. The microstructure of healing tendons was observed by scanning electron microscopy. Reverse-transcription polymerase chain reaction (RT-PCR) was performed to measure the ratio of type III collagen messenger RNA (mRNA) to type I collagen mRNA in tendons. The median Bonar scale score in the ASC and PBS groups was 2.5 and 5.33 at 4 weeks after treatment and 1.0 and 4.0 at 12 weeks after treatment, respectively. Histologically, the ASC group showed a significantly lower degree of tendon degeneration than the PBS group at both time points. In the RT-PCR analysis, the ratio of type III collagen to type I collagen was significantly lower in the ASC group than in the PBS group at 12 weeks after treatment. Moreover, this ratio decreased over time in the ASC group, whereas it increased over time in the PBS group. The study findings demonstrate that the application of ASCs results in significant improvement in the

  7. 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

  8. Impact of IUdR on Rat 9L glioma cell survival for 25-35 keV photon-activated auger electron therapy.

    Science.gov (United States)

    Alvarez, Diane; Hogstrom, Kenneth R; Brown, Thomas A D; Ii, Kenneth L Matthews; Dugas, Joseph P; Ham, Kyungmin; Varnes, Marie E

    2014-12-01

    The goal of the current study was to measure the energy dependence of survival of rat 9L glioma cells labeled with iododeoxyuridine (IUdR) that underwent photon-activated Auger electron therapy using 25-35 keV monochromatic X rays, i.e., above and below the K-edge energy of iodine. Rat 9L glioma cells were selected because of their radioresistance, ability to be implanted for future in vivo studies and analogy to radioresistant human gliomas. Survival curves were measured for a 4 MV X-ray beam and synchrotron produced monochromatic 35, 30 and 25 keV X-ray beams. IUdR was incorporated into the DNA at levels of 0, 9 and 18% thymidine replacement for 4 MV and 35 keV and 0 and 18% thymidine replacement for 30 and 25 keV. For 10 combinations of beam energy and thymidine replacement, 62 data sets (3-13 per combination) provided 776 data points (47-148 per combination). Survival versus dose data taken for the same combination, but on different days, were merged by including the zero-dose points in the nonlinear, chi-squared data fitting using the linear-quadratic model and letting the best estimate to the zero-dose plating efficiency for each of the different days be a fitting parameter. When comparing two survival curves, the ratio of doses resulting in 10% survival gave sensitization enhancement ratios (SER10) from which contributions due to linear energy transfer (LET) (SER10,LET), IUdR radiosensitization (SER10,RS), the Auger effect (SER10,AE) and the total of all effects (SER10,T) were determined. At 4 MV and 35, 30 and 25 keV, SER10,LET values were 1.00, 1.08 ± 0.03, 1.22 ± 0.02 and 1.37 ± 0.02, respectively. At 4 MV SER10,RS values for 9 and 18% IUdR were 1.28 ± 0.02 and 1.40 ± 0.02, respectively. Assuming LET effects were independent of percentage IUdR and radiosensitization effects were independent of energy, SER10,AE values for 18% IUdR at 35, 30 and 25 keV were 1.35 ± 0.05, 1.06 ± 0.03 and 0.98 ± 0.03, respectively. The value for 9% IUdR at 35 keV was 1

  9. Physiologically based pharmacokinetic modeling of tea catechin mixture in rats and humans.

    Science.gov (United States)

    Law, Francis C P; Yao, Meicun; Bi, Hui-Chang; Lam, Stephen

    2017-06-01

    Although green tea ( Camellia sinensis) (GT) contains a large number of polyphenolic compounds with anti-oxidative and anti-proliferative activities, little is known of the pharmacokinetics and tissue dose of tea catechins (TCs) as a chemical mixture in humans. The objectives of this study were to develop and validate a physiologically based pharmacokinetic (PBPK) model of tea catechin mixture (TCM) in rats and humans, and to predict an integrated or total concentration of TCM in the plasma of humans after consuming GT or Polyphenon E (PE). To this end, a PBPK model of epigallocatechin gallate (EGCg) consisting of 13 first-order, blood flow-limited tissue compartments was first developed in rats. The rat model was scaled up to humans by replacing its physiological parameters, pharmacokinetic parameters and tissue/blood partition coefficients (PCs) with human-specific values. Both rat and human EGCg models were then extrapolated to other TCs by substituting its physicochemical parameters, pharmacokinetic parameters, and PCs with catechin-specific values. Finally, a PBPK model of TCM was constructed by linking three rat (or human) tea catechin models together without including a description for pharmacokinetic interaction between the TCs. The mixture PBPK model accurately predicted the pharmacokinetic behaviors of three individual TCs in the plasma of rats and humans after GT or PE consumption. Model-predicted total TCM concentration in the plasma was linearly related to the dose consumed by humans. The mixture PBPK model is able to translate an external dose of TCM into internal target tissue doses for future safety assessment and dose-response analysis studies in humans. The modeling framework as described in this paper is also applicable to the bioactive chemical in other plant-based health products.

  10. 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)

  11. 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.

  12. [Analysis of tropalgin effects in an inflammation pain model in rats with different pain threshold].

    Science.gov (United States)

    Zarubina, I V; Fedorova, O N; Shabanov, P D

    2015-01-01

    Individual pain sensitivity of male Wistar rats was determined in a tail-flick model after action of focused thermal ray (flick) on tail. Rats with latency less than 5 sec were qualified as high sensitive (HS) to pain, more than 10 sec as low sensitive (LS) to pain. Effects of a new nonopioid analgetic tropalgin 2 mg/kg (ED50) i.p. was studied in both groups of rats. Tropalgin was effective as an analgetic in aseptic inflammation model (formaldehyde test). The analgetic effects of tropalgin were same as after administration of methamizol sodium (50 mg/kg) or diclofenac sodium (7 mg/kg). Tropalgin did not change individual pain sensitivity in both HS and LS rats without inflammation. In HS to pain rats, the common time of pain behavioral reactions was decreased by 53% in an acute phase of pain and by 58% in a tonic phase of pain in inflammation pain model. In LS to pain rats, the time of leaking of inflamed paw was decreased by 42% in the first phase and by 66% in the second phase. We suggest that analgetic effect of tropalgin is connected with adenosine release in purinergic neurons that has been demonstrated earlier for drugs of tropin structure.

  13. Protective effects of leflunomide on renal lesions in a rat model if diabetic nephropathy.

    Science.gov (United States)

    Zhang, Qing; Ji, Yongqiang; Lv, Wei; He, Tianwei; Wang, Jianping

    2016-01-01

    Diabetic nephropathy is one of the most common chronic complications of diabetes with poor efficacy of clinical treatment. This study investigated the protective effects of leflunomide, a new immunosuppressant, on tubulointerstitial lesions in a rat model of diabetic nephropathy. Diabetes was induced with streptozotocin (STZ, 50 mg/kg) by intraperitoneal injection in male Wistar rats. Two weeks after STZ injection, diabetic rats were treated daily for 8 weeks with low (5 mg/kg) and high dose (10 mg/kg) of leflunomide, and benazepril hydrochloride (4 mg/kg) as a positive control. In diabetic rats, the 24-h urine volume, urine protein and microalbumin, blood creatinine and urea nitrogen significantly increased, which were attenuated by leflunomide treatment in a dose-dependent manner (all p diabetic rats were mitigated by leflunomide treatment. Immunohistochemistry study and real-time polymerase chain reaction results demonstrated that osteopontin (OPN), transforming growth factor beta 1 (TGF-β1), α-smooth muscle actin and CD68 expression in the renal tubulointerstitial region were significantly increased in the diabetic rats, while these increases were inhibited by leflunomide treatment. These findings suggest that leflunomide protects the kidney injury of diabetic rats might through its inhibition of OPN/TGF-β1 mediated extracellular matrix deposition and tubulointerstitial fibrosis, as well as its inhibition on tubular epithelial-myofibroblast transdifferentiation.

  14. Effect of Bile Acid on Fetal Lung in Rat Model of Intrahepatic Cholestasis of Pregnancy

    Directory of Open Access Journals (Sweden)

    Ling Yu

    2014-01-01

    Full Text Available Objective. To determine the correlation between maternal bile acid (BA level and fetal pulmonary surfactant in rats and study the effects of BA on fetal lung in rat model of intrahepatic cholestasis of pregnancy. Methods. Forty pregnant rats were treated with (A 5.5 mg/kg BA, (B 1.4 mg/kg BA, and (C 1 ml physiological saline. Levels of total bile acid (TBA, ALT, AST, TBIL, DBIL, and SP-A were determined and the lungs of fetal rats were analyzed for pathological changes. Results. Groups A and B intervened with BA showed significant higher level of TBA in both maternal and fetal serum, more mortality rate of fetal rats, more concentration of SP-A in fetal serum, and wider alveolus mesenchyme of fetal rats than the control Group C. Higher level of BA associated with increased fetal risk and lower numerical density of mitochondria in type II alveolar epithelial cells. The levels of TBA in maternal serum were found to have significant positive correlation with those in fetal serum and SP-A level but negatively with the area of alveolus and the numerical density of lamellar body. Conclusions. The TBA level in maternal serum showed significant association with lung pathological changes in fetal rats.

  15. [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

  16. Evaluation of the effects of photobiomodulation on vertebras in two rat models of experimental osteoporosis.

    Science.gov (United States)

    Fredoni, Mohammadjavad; Ghatrehsamani, Mahdi; Abdollahifar, Mohammad-Amin; Bayat, Sahar; Bayat, Mohammad

    2017-09-01

    The aim of this study was to evaluate the effects of photobiomodulation (PBM) on cancellous bone in rat models of ovariectomized induced osteoporosis (OVX-D) and glucocorticoid-induced osteoporosis (GIOP). The experiment comprised of nine groups. A group of healthy rats was used for baseline evaluations. The OVX-D rats were further divided into groups as follows: control rats with osteoporosis, OVX-D rats that received alendronate (1 mg/kg 60 days), OVX-D rats treated with pulsed wave laser (890 nm, 80 Hz, 900 s, 0.0061 W/cm 2 , 5.5 J/cm 2 , three times a week, 60 days), and OVX-D rats treated with alendronate + pulsed laser. Dexamethasone was administered to the remaining rats that were split into four groups: control, alendronate-treated rats, laser-treated rats, and GIOP rats treated with alendronate + laser. T12, L1, L2, and L3 vertebrae were subjected to laser. Results of the current study demonstrated that OVX-D and GIOP significantly decreased some stereological parameters, and type 1 collagen gene expression compared to the healthy group. There was a significant increase in osteoclast number in both OVX-D and glucocorticoid administration compared to the healthy group. However, the detrimental effect of the OVX-D procedure on bone was more serious than glucocorticoid administration. Results showed that laser alone had a detrimental effect on trabecular bone volume, and cortical bone volume in groups GIOP and OVX-D compared to those in the healthy group. Alendronate significantly improved total vertebral bone volume, trabecular bone volume, and cortical bone volume, in GIOP and OVX-D groups compared to the laser-treated groups. Furthermore, the alendronate + laser in OVX-D rats and GIOP rats produced significantly increased osteoblast number and type 1 collagen gene expression and caused a significant decrease in osteoclast number compared to the controls.

  17. 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.

  18. ideal hepatotoxicity model in rats using carbon tetrachloride (ccl4)

    African Journals Online (AJOL)

    DR. AMINU

    Pharmacology Department, ABU Zaria and kept in the animal house of Physiology Department, Bayero. University Kano, Nigeria. The rats were kept under the same .... research thesis, Department of Biochemistry, post graduate school Bayero University, Kano. Tappel, A.L. (1972). Vitamin E and free radical peroxidation of ...

  19. 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...

  20. 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.

  1. 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

  2. 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 ...

  3. Electronic pairing mechanism due to band modification in a two-band model: Tc evaluation

    International Nuclear Information System (INIS)

    Mizia, J.; Gorski, G.; Traa, M.R.M.J.

    1997-01-01

    Following the electronic model developed by us previously (Mizia and Romanowski, Mizia) we estimate the superconducting transition temperature in a simple electronic two-band model for materials characterized by a broad superconducting band and a narrow level within the same energy range. A large electron deformation coupling constant and large electron correlation effects are assumed. It is shown that high-temperature superconductivity is entirely possible within a range of reasonable electronic parameters. This model does not assume any artificial interactions to obtain a negative pairing potential. Instead, the negative part of the electronic interaction potential comes from the modification of the electron dispersion relation with growing number of superconducting pairs. Such a modification is possible in soft electronic systems, i.e. in systems partial to band modification due to large internal stresses, strong electronic correlation effects and broad band narrow level charge transfer during the superconducting transition. (orig.)

  4. The methylazoxymethanol acetate (MAM-E17) rat model: molecular and functional effects in the hippocampus.

    Science.gov (United States)

    Hradetzky, Eva; Sanderson, Thomas M; Tsang, Tsz M; Sherwood, John L; Fitzjohn, Stephen M; Lakics, Viktor; Malik, Nadia; Schoeffmann, Stephanie; O'Neill, Michael J; Cheng, Tammy Mk; Harris, Laura W; Rahmoune, Hassan; Guest, Paul C; Sher, Emanuele; Collingridge, Graham L; Holmes, Elaine; Tricklebank, Mark D; Bahn, Sabine

    2012-01-01

    Administration of the DNA-alkylating agent methylazoxymethanol acetate (MAM) on embryonic day 17 (E17) produces behavioral and anatomical brain abnormalities, which model some aspects of schizophrenia. This has lead to the premise that MAM rats are a neurodevelopmental model for schizophrenia. However, the underlying molecular pathways affected in this model have not been elucidated. In this study, we investigated the molecular phenotype of adult MAM rats by focusing on the frontal cortex and hippocampal areas, as these are known to be affected in schizophrenia. Proteomic and metabonomic analyses showed that the MAM treatment on E17 resulted primarily in deficits in hippocampal glutamatergic neurotransmission, as seen in some schizophrenia patients. Most importantly, these results were consistent with our finding of functional deficits in glutamatergic neurotransmission, as identified using electrophysiological recordings. Thus, this study provides the first molecular evidence, combined with functional validation, that the MAM-E17 rat model reproduces hippocampal deficits relevant to the pathology of schizophrenia.

  5. The rat model in microsurgery education: classical exercises and new horizons.

    Science.gov (United States)

    Shurey, Sandra; Akelina, Yelena; Legagneux, Josette; Malzone, Gerardo; Jiga, Lucian; Ghanem, Ali Mahmoud

    2014-05-01

    Microsurgery is a precise surgical skill that requires an extensive training period and the supervision of expert instructors. The classical training schemes in microsurgery have started with multiday experimental courses on the rat model. These courses have offered a low threat supervised high fidelity laboratory setting in which students can steadily and rapidly progress. This simulated environment allows students to make and recognise mistakes in microsurgery techniques and thus shifts any related risks of the early training period from the operating room to the lab. To achieve a high level of skill acquisition before beginning clinical practice, students are trained on a comprehensive set of exercises the rat model can uniquely provide, with progressive complexity as competency improves. This paper presents the utility of the classical rat model in three of the earliest microsurgery training centres and the new prospects that this versatile and expansive training model offers.

  6. [Analysis on establishment and affecting factors of qi stagnation and blood stasis rat model].

    Science.gov (United States)

    Wang, Tingting; Jia, Cheng; Chen, Yu; Li, Xin; Cheng, Jiayi

    2012-06-01

    To study on the method for establishing the Qi stagnation and blood stasis rat model and analyze the affecting factors. The orthogonal design was adopted to study the influences of joint stimulations including noise, light, electricity, ice water bath, tail-clamping on model rats. The 'flying spot' method was used to dynamically simulate blood flow velocity in microcirculation. the pressure sensing technology of MOTO was adopted to detect hemorheology-related indicators. And the coagulation method was used to detect blood coagulation-related indicators. Compared with the negative control group, all model groups showed significant reduction in the blood flow velocity in mesenteric microcirculation and increase in the whole blood viscosity at high, medium and low shear rate, the plasma viscosity and the fibrinogen content in four blood coagulation indicators. Noise, light, electricity, tail-clamping, bondage and icewater-bath make significant impact on model rats.

  7. Improving high-altitude emp modeling capabilities by using a non-equilibrium electron swarm model to monitor conduction electron evolution

    Science.gov (United States)

    Pusateri, Elise Noel

    An Electromagnetic Pulse (EMP) can severely disrupt the use of electronic devices in its path causing a significant amount of infrastructural damage. EMP can also cause breakdown of the surrounding atmosphere during lightning discharges. This makes modeling EMP phenomenon an important research effort in many military and atmospheric physics applications. EMP events include high-energy Compton electrons or photoelectrons that ionize air and produce low energy conduction electrons. A sufficient number of conduction electrons will damp or alter the EMP through conduction current. Therefore, it is important to understand how conduction electrons interact with air in order to accurately predict the EMP evolution and propagation in the air. It is common for EMP simulation codes to use an equilibrium ohmic model for computing the conduction current. Equilibrium ohmic models assume the conduction electrons are always in equilibrium with the local instantaneous electric field, i.e. for a specific EMP electric field, the conduction electrons instantaneously reach steady state without a transient process. An equilibrium model will work well if the electrons have time to reach their equilibrium distribution with respect to the rise time or duration of the EMP. If the time to reach equilibrium is comparable or longer than the rise time or duration of the EMP then the equilibrium model would not accurately predict the conduction current necessary for the EMP simulation. This is because transport coefficients used in the conduction current calculation will be found based on equilibrium reactions rates which may differ significantly from their non-equilibrium values. We see this deficiency in Los Alamos National Laboratory's EMP code, CHAP-LA (Compton High Altitude Pulse-Los Alamos), when modeling certain EMP scenarios at high altitudes, such as upward EMP, where the ionization rate by secondary electrons is over predicted by the equilibrium model, causing the EMP to short

  8. Inflammatory responses in two commonly used rat models for experimental tooth movement: comparison with ligature-induced periodontitis

    NARCIS (Netherlands)

    Xie, R.; Kuijpers-Jagtman, A.M.; Maltha, J.C.

    2011-01-01

    OBJECTIVE: To compare two often used rat models for experimental tooth movement, namely the elastic band, and the coil spring model. They were compared with a silk-ligature-induced periodontitis model. DESIGN: Thirty six, 6-weeks-old rats were used. In a split mouth design four experimental

  9. The role of intestinal endotoxemia in a rat model of aluminum neurotoxicity.

    Science.gov (United States)

    Wang, Feng; Guo, Rui-Xia; Li, Wen-Xing; Yu, Bao-Feng; Han, Bai; Liu, Li-Xin; Han, De-Wu

    2017-08-01

    The present study aimed to investigate the effects of intestinal endotoxemia (IETM) in a rat model of aluminum neurotoxicity established by D-galactose and aluminum trichloride (AlCl3). Adult Wistar rats were administered D‑galactose and AlCl3 to create the aluminum neurotoxicity model. The learning and memory abilities of the rats were subsequently observed using a Morris water maze test and the serum levels of lipopolysaccharide (LPS), tumor necrosis factor (TNF)‑α, interleukin (IL)‑1, diamine oxidase (DAO), glutamine (Gln) and glutaminase were measured. The expression of S‑100β in the serum was detected using an enzyme‑linked immunosorbent assay. The expression levels of the amyloid β‑protein (Aβ) precursor (APP), presenilin 1 (PS1), β‑site APP‑cleaving enzyme (BACE), zona occludens protein (ZO)‑1 and Aβ 1‑40 in the brain of rats were detected via reverse‑transcription polymerase chain reaction, western blotting and immunohistochemistry. The levels of LPS, TNF‑α, IL‑1, DAO, Gln and S‑100β in serum and the mRNA and protein expression levels of APP, PS1, BACE and Aβ1‑40 in the brain were markedly increased in the model rats compared with controls. The level of glutaminase in the serum and the expression of ZO‑1 in the brain were decreased in the model rats compared with controls. IETM was present in the rat model of aluminum neurotoxicity established by D‑galactose and AlCl3 and may be important in the development of this neurotoxicity.

  10. A gliotoxin model of occipital seizures in rats.

    Science.gov (United States)

    Mirsattari, Seyed M; Shen, Bixia; Leung, L Stan; Rajakumar, Nagalingam

    2008-09-01

    Intracortical microinjection of fluorocitrate, a reversible inhibitor of glial tricarboxylic acid (TCA), results in impaired glial metabolism and epileptic seizures. To determine the potential contribution of epileptic activities to the metabolic properties of fluorocitrate, we investigated the seizure-inducing property of fluorocitrate at different doses. Twenty-seven male Sprague Dawley rats (250-400g) were studied with chronically implanted electrodes and cannulae in the occipital cortices. A week after surgery, awake behaving rats were injected with 0.2microl solution containing various concentrations of fluorocitrate or saline in the right occipital cortex; two sham-treated animals did not receive an injection. EEG was recorded with implanted electrodes. Thionin staining was used to verify injection sites. Twenty rats underwent immunohistochemistry for glial fibrilary acidic protein (GFAP) and neuronal nuclear-specific antigen (NeuN) 48h after the injections. Seizures developed within an hour of injection in all the rats that received > or =0.8nmol fluorocitrate and 2 of 4 rats that received 0.4nmol fluorocitrate. Five of 12 animals that received > or =1.2nmol fluorocitrate experienced status epilepticus. There was a significant increase in GFAP staining at the injection site in doses > or =0.8nmol fluorocitrate. There was only mild neuronal loss revealed by NeuN staining at the injection site in the animals that had received 1.6nmol flourocitrate. This study shows that fluorocitrate results in focal epileptic seizures with secondary generalization in a dose-dependent manner, including low doses of this agent previously used for studies of brain metabolism.

  11. Modeling neuro-vascular coupling in rat cerebellum: characterization of deviations from linearity

    DEFF Research Database (Denmark)

    Rasmussen, Tina; Holstein-Rathlou, Niels-Henrik; Lauritzen, Martin

    2009-01-01

    We investigated the quantitative relation between neuronal activity and blood flow by means of a general parametric mathematical model which described the neuro-vascular system as being dynamic, linear, time-invariant, and subjected to additive noise. The model was constructed from measurements...... for linearizability. We exercised the model on data from rat cerebellar cortex. In anesthetized rats, stimulation of the inferior olive caused climbing fiber activity and blood flow changes. Field potential amplitudes were used as an indicator of neuronal activity and blood flow was measured by laser...

  12. Lumped Parameter Modeling for Rapid Vibration Response Prototyping and Test Correlation for Electronic Units

    Science.gov (United States)

    Van Dyke, Michael B.

    2013-01-01

    Present preliminary work using lumped parameter models to approximate dynamic response of electronic units to random vibration; Derive a general N-DOF model for application to electronic units; Illustrate parametric influence of model parameters; Implication of coupled dynamics for unit/board design; Demonstrate use of model to infer printed wiring board (PWB) dynamics from external chassis test measurement.

  13. Light microscopic distribution and electron microscopic identification of severely damaged cells in x-irradiated oral epithelium in rat

    International Nuclear Information System (INIS)

    Liu, H.M.; Meyer, J.; Waterhouse, J.P.

    1975-01-01

    After x irradiation with a single dose of 5000 R to the lower lip of shielded rats, the responses of the epithelium of the mucosa were studied at 2, 6, 26, and 50 hr by light and electron microscopy. Light microscopy showed sharp contrasts in the intensity of staining among the irradiated basal cells, and the presence of focally distributed dark cells. These were identified in the electron microscope as degenerating cells with condensed nuclear and cytoplasmic contents and degenerate organelles. Quantitative analysis of the pattern of distribution of dark cells revealed a marked increase in over-all frequency, pairing, and formation of larger clusters by 50 hr. At this time dark cells were 11.6 percent of the total number of the basal cells and the largest cluster consisted of 12 adjacent cells. The distribution of dark cells at 50 hr fitted the negative binomial distribution (goodness of fit, chi 2 = 5.03, p = 0.185) and showed significant clustering. The mechanism of pair and cluster formation is discussed. (U.S.)

  14. A Massless-Point-Charge Model for the Electron

    Directory of Open Access Journals (Sweden)

    Daywitt W. C.

    2010-04-01

    Full Text Available "It is rather remarkable that the modern concept of electrodynamics is not quite 100 years old and yet still does not rest firmly upon uniformly accepted theoretical foundations. Maxwell's theory of the electromagnetic field is firmly ensconced in modern physics, to be sure, but the details of how charged particles are to be coupled to this field remain somewhat uncertain, despite the enormous advances in quantum electrodynamics over the past 45 years. Our theories remain mathematically ill-posed and mired in conceptual ambiguities which quantum mechanics has only moved to another arena rather than resolve. Fundamentally, we still do not understand just what is a charged particle" (Grandy W.T. Jr. Relativistic quantum mechanics of leptons and fields. Kluwer Academic Publishers, Dordrecht-London, 1991, p.367. As a partial answer to the preceeding quote, this paper presents a new model for the electron that combines the seminal work of Puthoff with the theory of the Planck vacuum (PV, the basic idea for the model following from Puthoff with the PV theory adding some important details.

  15. Electron percolation in realistic models of carbon nanotube networks

    Science.gov (United States)

    Simoneau, Louis-Philippe; Villeneuve, Jérémie; Rochefort, Alain

    2015-09-01

    The influence of penetrable and curved carbon nanotubes (CNT) on the charge percolation in three-dimensional disordered CNT networks have been studied with Monte-Carlo simulations. By considering carbon nanotubes as solid objects but where the overlap between their electron cloud can be controlled, we observed that the structural characteristics of networks containing lower aspect ratio CNT are highly sensitive to the degree of penetration between crossed nanotubes. Following our efficient strategy to displace CNT to different positions to create more realistic statistical models, we conclude that the connectivity between objects increases with the hard-core/soft-shell radii ratio. In contrast, the presence of curved CNT in the random networks leads to an increasing percolation threshold and to a decreasing electrical conductivity at saturation. The waviness of CNT decreases the effective distance between the nanotube extremities, hence reducing their connectivity and degrading their electrical properties. We present the results of our simulation in terms of thickness of the CNT network from which simple structural parameters such as the volume fraction or the carbon nanotube density can be accurately evaluated with our more realistic models.

  16. Electron beam lithographic modeling assisted by artificial intelligence technology

    Science.gov (United States)

    Nakayamada, Noriaki; Nishimura, Rieko; Miura, Satoru; Nomura, Haruyuki; Kamikubo, Takashi

    2017-07-01

    We propose a new concept of tuning a point-spread function (a "kernel" function) in the modeling of electron beam lithography using the machine learning scheme. Normally in the work of artificial intelligence, the researchers focus on the output results from a neural network, such as success ratio in image recognition or improved production yield, etc. In this work, we put more focus on the weights connecting the nodes in a convolutional neural network, which are naturally the fractions of a point-spread function, and take out those weighted fractions after learning to be utilized as a tuned kernel. Proof-of-concept of the kernel tuning has been demonstrated using the examples of proximity effect correction with 2-layer network, and charging effect correction with 3-layer network. This type of new tuning method can be beneficial to give researchers more insights to come up with a better model, yet it might be too early to be deployed to production to give better critical dimension (CD) and positional accuracy almost instantly.

  17. Python framework for kinetic modeling of electronically excited reaction pathways

    Science.gov (United States)

    Verboncoeur, John; Parsey, Guy; Guclu, Yaman; Christlieb, Andrew

    2012-10-01

    The use of plasma energy to enhance and control the chemical reactions during combustion, a technology referred to as ``plasma assisted combustion'' (PAC), can result in a variety of beneficial effects: e.g. stable lean operation, pollution reduction, and wider range of p-T operating conditions. While experimental evidence abounds, theoretical understanding of PAC is at best incomplete, and numerical tools still lack in reliable predictive capabilities. In the context of a joint experimental-numerical effort at Michigan State University, we present here an open-source modular Python framework dedicated to the dynamic optimization of non-equilibrium PAC systems. Multiple sources of experimental reaction data, e.g. reaction rates, cross-sections and oscillator strengths, are used in order to quantify the effect of data uncertainty and limiting assumptions. A collisional-radiative model (CRM) is implemented to organize reactions by importance and as a potential means of measuring a non-Maxwellian electron energy distribution function (EEDF), when coupled to optical emission spectroscopy data. Finally, we explore scaling laws in PAC parameter space using a kinetic global model (KGM) accelerated with CRM optimized reaction sequences and sparse stiff integrators.

  18. Betulinic acid attenuates renal fibrosis in rat chronic kidney disease model.

    Science.gov (United States)

    Sharma, Anshuk; Thakur, Richa; Lingaraju, Madhu C; Kumar, Dhirendra; Mathesh, Karikalan; Telang, Avinash G; Singh, Thakur Uttam; Kumar, Dinesh

    2017-05-01

    Most chronic kidney diseases (CKDs), regardless of the nature of the initial injury, progress to end-stage renal disease (ESRD) characterized by fibrosis with irreversible loss of tissue and function. Thus, improved and more effective therapies are critical. Betulinic acid (BA), a pentacyclic triterpene is a compound in the pipeline of anti-cancer drug development. It has been shown to a possess variety of beneficial effects in many disease conditions. However, its efficacy against CKD is yet to be explored. The present study was undertaken to investigate the effect of BA on renal fibrosis in the rat model of adenine-induced CKD. CKD rats gained significantly less weight during the experimental period when compared to control rats and BA treatment did not significantly increase the weight gain in CKD rats. CKD rats showed elevated levels of serum blood urea nitrogen (BUN), creatinine and uric acid along with increased levels of kidney injury markers such as cystatin C and neutrophil gelatinase-associated lipocalin (NGAL). Further, in comparison to control rats, kidney samples from CKD rats revealed increased profibrotic protein levels like transforming growth factor-beta (TGF-β), connective tissue growth factor (CTGF), fibronectin, collagen type I and hydroxyproline indicating a progressive fibrotic response. These data are further fortified by histological findings where kidney damage and fibrosis are clearly evident as dilatation of tubules, glomerular degeneration and vacuolation along with deposition of collagen fibers. However, the above-mentioned findings in CKD rats were significantly reversed by BA-treatment revealing its nephroprotective potential and anti-fibrotic activity. The biochemical mechanism of the nephroprotective and anti-fibrotic effect of BA in the adenine-induced CKD rats might be mediated by inhibition of pro-fibrotic protein production thereby hindering the kidney tissue damage along with improvement in kidney function. Thus, BA could be

  19. 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 animal study revealed that there were more fusions in rats that received 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.

  20. Different emotional disturbances in two experimental models of temporal lobe epilepsy in rats.

    Directory of Open Access Journals (Sweden)

    Marion Inostroza

    Full Text Available Affective symptoms such as anxiety and depression are frequently observed in patients with epilepsy. The mechanisms of comorbidity of epilepsy and affective disorders, however, remain unclear. Diverse models are traditionally used in epilepsy research, including the status epilepticus (SE model in rats, which are aimed at generating chronic epileptic animals; however, the implications of different SE models and rat strains in emotional behaviors has not been reported. To address this issue, we examined the emotional sequelae of two SE models of temporal lobe epilepsy (TLE--the lithium-pilocarpine (LIP model and the kainic acid (KA model--in two different rat strains (Wistar and Sprague-Dawley, which differ significantly in the pattern and extent of TLE-associated brain lesions. We found differences between LIP- and KA-treated animals in tests for depression-like and anxiety-like behaviors, as well as differences in plasma corticosterone levels. Whereas only LIP-treated rats displayed increased motivation to consume saccharin, both SE models led to reduced motivation for social contact, with LIP-treated animals being particularly affected. Evaluation of behavior in the open field test indicated very low levels of anxiety in LIP-treated rats and a mild decrease in KA-treated rats compared to controls. After exposure to a battery of behavioral tests, plasma corticosterone levels were increased only in LIP-treated animals. This hyperactivity in the hypothalamus-pituitary-adrenocortical (HPA axis was highly correlated with performance in the open field test and the social interaction test, suggesting that comorbidity of epilepsy and emotional behaviors might also be related to other factors such as HPA axis function. Our results indicate that altered emotional behaviors are not inherent to the epileptic condition in experimental TLE; instead, they likely reflect alterations in anxiety levels related to model-dependent dysregulation of the HPA axis.

  1. 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.

  2. Loss of Parvalbumin in the Hippocampus of MAM Schizophrenia Model Rats Is Attenuated by Peripubertal Diazepam.

    Science.gov (United States)

    Du, Yijuan; Grace, Anthony A

    2016-11-01

    Loss of parvalbumin interneurons in the hippocampus is a robust finding in schizophrenia brains. Rats exposed during embryonic day 17 to methylazoxymethanol acetate exhibit characteristics consistent with an animal model of schizophrenia, including decreased parvalbumin interneurons in the ventral hippocampus. We reported previously that peripubertal administration of diazepam prevented the emergence of pathophysiology in adult methylazoxymethanol acetate rats. We used an unbiased stereological method to examine the impact of peripubertal diazepam treatment on parvalbumin interneuron number in the ventral subiculum, dentate gyrus of the hippocampus and the basolateral amygdala. Methylazoxymethanol acetate rats with peripubertal diazepam showed significantly more parvalbumin interneurons (3355±173 in the ventral subiculum, 1211±76 in the dentate gyrus) than methylazoxymethanol acetate without diazepam (2375±109 and 824±54, respectively). No change was found in the basolateral amygdala. Peripubertal diazepam attenuated the decrease of parvalbumin in the ventral hippocampus of methylazoxymethanol acetate rats. © The Author 2016. Published by Oxford University Press on behalf of CINP.

  3. Speech sound discrimination training improves auditory cortex responses in a rat model of autism

    Directory of Open Access Journals (Sweden)

    Crystal T Engineer

    2014-08-01

    Full Text Available Children with autism often have language impairments and degraded cortical responses to speech. Extensive behavioral interventions can improve language outcomes and cortical responses. Prenatal exposure to the antiepileptic drug valproic acid (VPA increases the risk for autism and language impairment. Prenatal exposure to VPA also causes weaker and delayed auditory cortex responses in rats. In this study, we document speech sound discrimination ability in VPA exposed rats and document the effect of extensive speech training on auditory cortex responses. VPA exposed rats were significantly impaired at consonant, but not vowel, discrimination. Extensive speech training resulted in both stronger and faster anterior auditory field responses compared to untrained VPA exposed rats, and restored responses to control levels. This neural response improvement generalized to non-trained sounds. The rodent VPA model of autism may be used to improve the understanding of speech processing in autism and contribute to improving language outcomes.

  4. Transgenic rat model of neurodegeneration caused by mutation in the TDP gene.

    Science.gov (United States)

    Zhou, Hongxia; Huang, Cao; Chen, Han; Wang, Dian; Landel, Carlisle P; Xia, Pedro Yuxing; Bowser, Robert; Liu, Yong-Jian; Xia, Xu Gang

    2010-03-26

    TDP-43 proteinopathies have been observed in a wide range of neurodegenerative diseases. Mutations in the gene encoding TDP-43 (i.e., TDP) have been identified in amyotrophic lateral sclerosis (ALS) and in frontotemporal lobe degeneration associated with motor neuron disease. To study the consequences of TDP mutation in an intact system, we created transgenic rats expressing normal human TDP or a mutant form of human TDP with a M337V substitution. Overexpression of mutant, but not normal, TDP caused widespread neurodegeneration that predominantly affected the motor system. TDP mutation reproduced ALS phenotypes in transgenic rats, as seen by progressive degeneration of motor neurons and denervation atrophy of skeletal muscles. This robust rat model also recapitulated features of TDP-43 proteinopathies including the formation of TDP-43 inclusions, cytoplasmic localization of phosphorylated TDP-43, and fragmentation of TDP-43 protein. TDP transgenic rats will be useful for deciphering the mechanisms underlying TDP-43-related neurodegenerative diseases.

  5. 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

  6. Bone marrow mesenchymal stem cells combined with minocycline improve spinal cord injury in a rat model.

    Science.gov (United States)

    Chen, Dayong; Zeng, Wei; Fu, Yunfeng; Gao, Meng; Lv, Guohua

    2015-01-01

    The aims of this study were to assess that the effects of bone marrow mesenchymal stem cells (BMSCs) combination with minocycline improve spinal cord injury (SCI) in rat model. In the present study, the Wistar rats were randomly divided into five groups: control group, SCI group, BMSCs group, Minocycline group and BMSCs + minocycline group. Basso, Beattie and Bresnahan (BBB) test and MPO activity were used to assess the effect of combination therapy on locomotion and neutrophil infiltration. Inflammation factors, VEGF and BDNF expression, caspase-3 activation, phosphorylation-p38MAPK, proNGF, p75NTR and RhoA expressions were estimated using commercial kits or western blot, respectively. BBB scores were significantly increased and MPO activity was significantly undermined by combination therapy. In addition, combination therapy significantly decreased inflammation factors in SCI rats. Results from western blot showed that combination therapy significantly up-regulated the protein of VEGF and BDNF expression and down-regulated the protein of phosphorylation-p38MAPK, proNGF, p75NTR and RhoA expressions in SCI rats. Combination therapy stimulation also suppressed the caspase-3 activation in SCI rats. These results demonstrated that the effects of bone marrow mesenchymal stem cells combination with minocycline improve SCI in rat model.

  7. 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

  8. 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

  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. 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.

  11. Longitudinal MRI monitoring of brain damage in the neonatal ventral hippocampal lesion rat model of schizophrenia.

    Science.gov (United States)

    Bertrand, Jean-Baptiste; Langlois, Jean-Baptiste; Bégou, Mélina; Volle, Julien; Brun, Philippe; d'Amato, Thierry; Saoud, Mohamed; Suaud-Chagny, Marie-Françoise

    2010-02-01

    Rat with excitotoxic neonatal ventral hippocampal lesions (NVHL rats) is considered as a heuristic neurodevelopmental model for studying schizophrenia. Extensive study of this model is limited by the lack of clear validity criteria of such lesions and because ascertaining of the lesions is realized postmortem with histological examination after completing experiments. Here, in a first experiment, by assessing the locomotor response to amphetamine in adult NVHL rats, we further specify that the lesions must be bilateral and confined to the ventral hippocampus to obtain the validated behavioral phenotype. We then show a longitudinal magnetic resonance imaging (MRI) protocol suitable for the detection of brain structural changes in NVHL rats. The T(2)-weighted images acquired in adult NVHL rats reveal the same structural changes as those appraised with histological protocol. Moreover, we demonstrate that the lesion status in adulthood can be accurately predicted from the T(2)-weighted images acquired in the juvenile period. As technical advantages, our MRI protocol makes possible to select animals according to lesion criteria as soon as in the juvenile period before long-lasting experiments and gives access in vivo to a quantitative parameter indicative of the lesion extent. Finally, we show that the lesion size increases only slightly between juvenile and adult periods. These latter results are discussed in the context of the specific postpubertal emergence of the behavioral deficits in NVHL rats.

  12. Effect of Coenzyme Q10 on ischemia and neuronal damage in an experimental traumatic brain-injury model in rats

    Directory of Open Access Journals (Sweden)

    Hanci Volkan

    2011-07-01

    Full Text Available Abstract Background Head trauma is one of the most important clinical issues that not only can be fatal and disabling, requiring long-term treatment and care, but also can cause heavy financial burden. Formation or distribution of free oxygen radicals should be decreased to enable fixing of poor neurological outcomes and to prevent neuronal damage secondary to ischemia after trauma. Coenzyme Q10 (CoQ10, a component of the mitochondrial electron transport chain, is a strong antioxidant that plays a role in membrane stabilization. In this study, the role of CoQ10 in the treatment of head trauma is researched by analyzing the histopathological and biochemical effects of CoQ10 administered after experimental traumatic brain injury in rats. A traumatic brain-injury model was created in all rats. Trauma was inflicted on rats by the free fall of an object of 450 g weight from a height of 70 cm on the frontoparietal midline onto a metal disc fixed between the coronal and the lambdoid sutures after a midline incision was carried out. Results In the biochemical tests, tissue malondialdehyde (MDA levels were significantly higher in the traumatic brain-injury group compared to the sham group (p 10 after trauma was shown to be protective because it significantly lowered the increased MDA levels (p 10 group had SOD levels ranging between those of sham group and traumatic brain-injury group, and no statistically significant increase was detected. Histopathological results showed a statistically significant difference between the CoQ10 and the other trauma-subjected groups with reference to vascular congestion, neuronal loss, nuclear pyknosis, nuclear hyperchromasia, cytoplasmic eosinophilia, and axonal edema (p Conclusion Neuronal degenerative findings and the secondary brain damage and ischemia caused by oxidative stress are decreased by CoQ10 use in rats with traumatic brain injury.

  13. Differential effects of B7-1 blockade in the rat experimental autoimmune encephalomyelitis model

    DEFF Research Database (Denmark)

    Gallon, L; Chandraker, A; Issazadeh-Navikas, Shohreh

    1997-01-01

    Blocking the CD28-B7 T cell costimulatory activation pathway protects animals from developing experimental autoimmune encephalomyelitis (EAE). In the mouse EAE model, selective blockade of B7-1 by specific mAbs has been shown to protect animals from EAE. In the Lewis rat model, we have shown that...

  14. Development and identification of a multicompartment model for the distribution of adriamycin in the rat

    NARCIS (Netherlands)

    Sonneveld, P.; Mulder, J.A.

    1981-01-01

    The distribution kinetics of adriamycin in the rat were analyzed by using a multicompartment mathematical model. The set of a priori unknown model parameters, the drug rate constants, were estimated from 48 hr multicompartment drug distribution data by applying multivariate system identification

  15. Profiling and Identification of Cerebrospinal Fluid Proteins in a Rat EAE Model of Multiple Sclerosis

    NARCIS (Netherlands)

    Rosenling, Therese; Stoop, Marcel P.; Attali, Amos; van Aken, Hans; Suidgeest, Ernst; Christin, Christin; Stingl, Christoph; Suits, Frank; Horvatovich, Peter; Hintzen, Rogier Q.; Tuinstra, Tinka; Bischoff, Rainer; Luider, Theo M.

    The experimental autoimmune encephalomyelitis (EAR) model resembles certain aspects of multiple sclerosis (MScl), with common features such as motor dysfunction, axonal degradation, and infiltration of T-cells. We studied the cerebrospinal fluid (CSF) proteome in the EAE rat model to identify

  16. Electron-microscopic examination of effects of yokukansan, a traditional Japanese medicine, on degeneration of cerebral cells in thiamine-deficient rats.

    Science.gov (United States)

    Iizuka, Seiichi; Kawakami, Zenji; Imamura, Sachiko; Yamaguchi, Takuji; Sekiguchi, Kyoji; Kanno, Hitomi; Ueki, Toshiyuki; Kase, Yoshio; Ikarashi, Yasushi

    2010-10-01

    We previously demonstrated that yokukansan ameliorated not only learning disturbance but also behavioral and psychological symptoms of dementia-like behaviors (anxiety, aggressiveness) and neurological symptoms (opisthotonus) induced in rats by dietary thiamine deficiency (TD). In the present study, the effects of yokukansan on degeneration of cerebral cells were further examined electron-microscopically during pre-symptomatic and symptomatic stages in TD rats. In the pre-symptomatic TD stage, which appeared as increase in aggressive behaviors on the 21st and 28th days of TD diet-feeding, severe edematous degeneration of astrocytes was detected by electron microscopy, although the changes were not observed by light microscopy. In the symptomatic TD stage (the 34th day) characterized by development of neurological symptoms, severe sponge-like degeneration and multiple hemorrhages in the parenchyma were obvious by light microscopy. The electron-microscopic examination showed degeneration in neurons, oligodendroglias, and myelin sheaths in addition to astrocytes. TD rats, which exhibited multiple hemorrhages light microscopically, showed severe edematous changes and hypertrophy of the foot processes of astrocytes surrounding blood vessels. Administration of yokukansan ameliorated not only the TD-induced aggressive behavior and neurological symptoms but also degeneration of the cerebral cells. These results suggest that the inhibitory effect of yokukansan on degeneration in various brain cells might be closely related to the amelioration of aggression and neurological symptoms in TD rats. © 2010 Japanese Society of Neuropathology.

  17. Modeling High Altitude EMP using a Non-Equilibrium Electron Swarm Model to Monitor Conduction Electron Evolution (LA-UR-15-26151)

    Science.gov (United States)

    Pusateri, E. N.; Morris, H. E.; Nelson, E.; Ji, W.

    2015-12-01

    Electromagnetic pulse (EMP) events in the atmosphere are important physical phenomena that occur through both man-made and natural processes, such as lightning, and can be disruptive to surrounding electrical systems. Due to the disruptive nature of EMP, it is important to accurately predict EMP evolution and propagation with computational models. In EMP, low-energy conduction electrons are produced from Compton electron or photoelectron ionizations with air. These conduction electrons continue to interact with the surrounding air and alter the EMP waveform. Many EMP simulation codes use an equilibrium ohmic model for computing the conduction current. The equilibrium model works well when the equilibration time is short compared to the rise time or duration of the EMP. However, at high altitude, the conduction electron equilibration time can be comparable to or longer than the rise time or duration of the EMP. This matters, for example, when calculating the EMP propagating upward toward a satellite. In these scenarios, the equilibrium ionization rate becomes very large for even a modest electric field. The ohmic model produces an unphysically large number of conduction electrons that prematurely and abruptly short the EMP in the simulation code. An electron swarm model, which simulates the time evolution of conduction electrons, can be used to overcome the limitations exhibited by the equilibrium ohmic model. We have developed and validated an electron swarm model in an environment characterized by electric field and pressure previously in Pusateri et al. (2015). This swarm model has been integrated into CHAP-LA, a state-of-the-art EMP code developed by researchers at Los Alamos National Laboratory, which previously calculated conduction current using an ohmic model. We demonstrate the EMP damping behavior caused by the ohmic model at high altitudes and show improvements on high altitude EMP modeling obtained by employing the swarm model.

  18. 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.

  19. Hydrogen coadministration slows the development of COPD-like lung disease in a cigarette smoke-induced rat model

    Directory of Open Access Journals (Sweden)

    Liu X

    2017-05-01

    Full Text Available Xiaoyu Liu,1,* Cuiqing Ma,2,* Xiaoyu Wang,1 Wenjing Wang,1 Zhu Li,1 Xiansheng Wang,1 Pengyu Wang,1 Wuzhuang Sun,1 Baojian Xue3 1Department of Respiratory Medicine, The First Hospital of Hebei Medical University, 2Department of Immunology, Hebei Medical University, Shijiazhuang, 3Life Science Research Center, Hebei North University, Zhangjiakou, People’s Republic of China *These authors contributed equally to this work Background: Chronic obstructive pulmonary disease (COPD is a progressive pulmonary disease caused by harmful gases or particles. Recent studies have shown that 2% hydrogen or hydrogen water is effective in the treatment and prevention of a variety of diseases. This study investigated the beneficial effects and the possible mechanisms of different hydrogen concentrations on COPD.Methods: A rat COPD model was established through smoke exposure methods, and inhalation of different concentrations of hydrogen was used as the intervention. The daily condition of rats and the weight changes were observed; lung function and right ventricular hypertrophy index were assessed. Also, white blood cells were assessed in bronchoalveolar lavage fluid. Pathologic changes in the lung tissue were analyzed using light microscopy and electron microscopy; cardiovascular structure and pulmonary arterial pressure changes in rats were observed using ultrasonography. Tumor necrosis factor alpha, interleukin (IL-6, IL-17, IL-23, matrix metalloproteinase-12, tissue inhibitor of metalloproteinase-1, caspase-3, caspase-8 protein, and mRNA levels in the lung tissue were determined using immunohistochemistry, Western blot, and real-time polymerase chain reaction.Results: The results showed that hydrogen inhalation significantly reduced the number of inflammatory cells in the bronchoalveolar lavage fluid, and the mRNA and protein expression levels of tumor necrosis factor alpha, IL-6, IL-17, IL-23, matrix metalloproteinase-12, caspase-3, and caspase-8, but

  20. Experimental tuberculosis in the Wistar rat: a model for protective immunity and control of infection.

    Directory of Open Access Journals (Sweden)

    Amit Singhal

    Full Text Available BACKGROUND: Despite the availability of many animal models for tuberculosis (TB research, there still exists a need for better understanding of the quiescent stage of disease observed in many humans. Here, we explored the use of the Wistar rat model for the study of protective immunity and control of Mycobacterium tuberculosis (Mtb infection. METHODOLOGY/PRINCIPAL FINDINGS: The kinetics of bacillary growth, evaluated by the colony stimulating assay (CFU and the extent of lung pathology in Mtb infected Wistar rats were dependent on the virulence of the strains and the size of the infecting inoculums. Bacillary growth control was associated with induction of T helper type 1 (Th1 activation, the magnitude of which was also Mtb strain and dose dependent. Histopathology analysis of the infected lungs demonstrated the formation of well organized granulomas comprising epithelioid cells, multinucleated giant cells and foamy macrophages surrounded by large numbers of lymphocytes. The late stage subclinical form of disease was reactivated by immunosuppression leading to increased lung CFU. CONCLUSION: The Wistar rat is a valuable model for better understanding host-pathogen interactions that result in control of Mtb infection and potentially establishment of latent TB. These properties together with the ease of manipulation, relatively low cost and well established use of rats in toxicology and pharmacokinetic analyses make the rat a good animal model for TB drug discovery.

  1. First principles based multiparadigm modeling of electronic structures and dynamics

    Science.gov (United States)

    Xiao, Hai

    enabling the tunability of CBO. We predict that Na further improves the CBO through electrostatically elevating the valence levels to decrease the CBO, explaining the observed essential role of Na for high performance. Moreover we find that K leads to a dramatic decrease in the CBO to 0.05 eV, much better than Na. We suggest that the efficiency of CIGS devices might be improved substantially by tuning the ratio of Na to K, with the improved phase stability of Na balancing phase instability from K. All these defects reduce interfacial stability slightly, but not significantly. A number of exotic structures have been formed through high pressure chemistry, but applications have been hindered by difficulties in recovering the high pressure phase to ambient conditions (i.e., one atmosphere and room temperature). Here we use dispersion-corrected DFT (PBE-ulg flavor) to predict that above 60 GPa the most stable form of N2O (the laughing gas in its molecular form) is a 1D polymer with an all-nitrogen backbone analogous to cis-polyacetylene in which alternate N are bonded (ionic covalent) to O. The analogous trans-polymer is only 0.03-0.10 eV/molecular unit less stable. Upon relaxation to ambient conditions both polymers relax below 14 GPa to the same stable non-planar trans-polymer, accompanied by possible electronic structure transitions. The predicted phonon spectrum and dissociation kinetics validate the stability of this trans-poly-NNO at ambient conditions, which has potential applications as a new type of conducting polymer with all-nitrogen chains and as a high-energy oxidizer for rocket propulsion. This work illustrates in silico materials discovery particularly in the realm of extreme conditions. Modeling non-adiabatic electron dynamics has been a long-standing challenge for computational chemistry and materials science, and the eFF method presents a cost-efficient alternative. However, due to the deficiency of FSG representation, eFF is limited to low-Z elements with

  2. Modeling Photovoltaic Module-Level Power Electronics in the System Advisor Model; NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-07-01

    Module-level power electronics, such as DC power optimizers, microinverters, and those found in AC modules, are increasing in popularity in smaller-scale photovoltaic (PV) systems as their prices continue to decline. Therefore, it is important to provide PV modelers with guidelines about how to model these distributed power electronics appropriately in PV modeling software. This paper extends the work completed at NREL that provided recommendations to model the performance of distributed power electronics in NREL’s popular PVWatts calculator [1], to provide similar guidelines for modeling these technologies in NREL's more complex System Advisor Model (SAM). Module-level power electronics - such as DC power optimizers, microinverters, and those found in AC modules-- are increasing in popularity in smaller-scale photovoltaic (PV) systems as their prices continue to decline. Therefore, it is important to provide PV modelers with guidelines about how to model these distributed power electronics appropriately in PV modeling software.

  3. 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.

  4. 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.

  5. Glutamatergic signaling and low prodynorphin expression are associated with intact memory and reduced anxiety in rat models of healthy aging

    Directory of Open Access Journals (Sweden)

    Caroline eMenard

    2014-05-01

    Full Text Available The LOU/C/Jall (LOU rat strain is considered a model of healthy aging due to its increased longevity, maintenance of stable body weight (BW throughout life and low incidence of age-related diseases. However, aging LOU rat cognitive and anxiety status has yet to be investigated. In the present study, male and female LOU rat cognitive performances (6-42 months were assessed using novel object recognition and Morris Water Maze tasks. Recognition memory remained intact in all LOU rats up to 42 months of age. As for spatial memory, old LOU rat performed similarly as young animals for learning acquisition, reversal learning and retention. While LOU rat BW remained stable despite aging, 20-month-old ad-libitum-fed (OAL male Sprague Dawley rats become obese. We determined if long-term caloric restriction (LTCR prevents age-related BW increase and cognitive deficits in this rat strain, as observed in the obesity-resistant LOU rats. Compared to young animals, recognition memory was impaired in OAL but intact in 20-month-old calorie-restricted (OCR rats. Similarly, OAL spatial learning acquisition was impaired but LTCR prevented the deficits. Exacerbated stress responses may favor age-related cognitive decline. In the elevated plus maze and open field tasks, LOU and OCR rats exhibited high levels of exploratory activity whereas OAL rats displayed anxious behaviors. Expression of prodynorphin (Pdyn, an endogenous peptide involved in stress-related memory impairments, was increased in the hippocampus of OAL rats. Group 1 metabotropic glutamate receptor 5 and immediate early genes Homer 1a and Arc expression, both associated with successful cognitive aging, were unaltered in aging LOU rats but lower in OAL than OCR rats. Altogether, our results, supported by principal component analysis and correlation matrix, suggest that intact memory and low anxiety are associated with glutamatergic signaling and low Pdyn expression in the hippocampus of non obese aging

  6. Orthosiphon stamineus (Misai Kucing) ameliorated postmenopausal osteoporosis in rat model.

    Science.gov (United States)

    Bokhari, Rubiatul Adawiyah; Lau, Seng Fong; Mohamed, Suhaila

    2018-02-01

    Orthosiphon stamineus (OS) or Misai Kucing (Java tea) is a popular herbal supplement from Southeast Asia for various metabolic, age-related diseases. This study investigated the potential use of OS leaf extracts to ameliorate osteoporosis in ovariectomized rats. Fifty-six female Sprague-Dawley rats were randomly allocated into eight groups (n = 7): SHAM (healthy sham control); OVX (ovarietomized) nontreated rats (negative control); OVX + Remifemin (100 mg/kg body weight), and 2% green tea extract (positive controls); OVX + OS 50% ethanolic and aqueous extracts, both at either 150 or 300 mg/kg. After 16 weeks, the rats' bones and blood were evaluated for osteoporosis indicators (protein and mRNA expressions), micro-computed tomography for bone histomorphometry, and three-point bending test for tibia mechanical strength. The extracts dose-dependently and significantly (P < 0.05) improved bone strength and flexibility, bone mineral density, bone formation protein markers (P1NP), and bone histomorphometry. All extracts reduced the inflammation biomarker (interleukin-6). The extracts up-regulated osteoblastogenesis (bone morphogenetic protein-2) and collagen-1 synthesis (collagen type 1 alpha-1) mRNA expressions, and down-regulated bone resorption (TNFSF11 and nuclear factor-kappa B) mRNA expressions. Both the water and 50% ethanolic extract were effective. The effective dose is equivalent to 25 to 50 mg/kg extract for humans. The extract showed bone-protective and antiosteoporotic effects (improving bone strength, flexibility, bone density, and bone morphometry) by reducing inflammation and the bone resorption biomarkers, while enhancing bone formation biomarkers and collagen synthesis.

  7. 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.

  8. 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

  9. 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.

  10. Modelling the main ionospheric trough using the Electron Density Assimilative Model (EDAM) with assimilated GPS TEC

    Science.gov (United States)

    Parker, James A. D.; Eleri Pryse, S.; Jackson-Booth, Natasha; Buckland, Rachel A.

    2018-01-01

    The main ionospheric trough is a large-scale spatial depletion in the electron density distribution at the interface between the high- and mid-latitude ionosphere. In western Europe it appears in early evening, progresses equatorward during the night, and retreats rapidly poleward at dawn. It exhibits substantial day-to-day variability and under conditions of increased geomagnetic activity it moves progressively to lower latitudes. Steep gradients on the trough-walls on either side of the trough minimum, and their variability, can cause problems for radio applications. Numerous studies have sought to characterize and quantify the trough behaviour. The Electron Density Assimilative Model (EDAM) models the ionosphere on a global scale. It assimilates observations into a background ionosphere, the International Reference Ionosphere 2007 (IRI2007), to provide a full 3-D representation of the ionospheric plasma distribution at specified times and days. This current investigation studied the capability of EDAM to model the ionosphere in the region of the main trough. Total electron content (TEC) measurements from 46 GPS stations in western Europe from September to December 2002 were assimilated into EDAM to provide a model of the ionosphere in the trough region. Vertical electron content profiles through the model revealed the trough and the detail of its structure. Statistical results are presented of the latitude of the trough minimum, TEC at the minimum and of other defined parameters that characterize the trough structure. The results are compared with previous observations made with the Navy Ionospheric Monitoring System (NIMS), and reveal the potential of EDAM to model the large-scale structure of the ionosphere.

  11. 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

  12. Modeling of Electronic Properties in Organic Semiconductor Device Structures

    Science.gov (United States)

    Chang, Hsiu-Chuang

    Organic semiconductors (OSCs) have recently become viable for a wide range of electronic devices, some of which have already been commercialized. With the mechanical flexibility of organic materials and promising performance of organic field effect transistors (OFETs) and organic bulk heterojunction devices, OSCs have been demonstrated in applications such as radio frequency identification tags, flexible displays, and photovoltaic cells. Transient phenomena play decisive roles in the performance of electronic devices and OFETs in particular. The dynamics of the establishment and depletion of the conducting channel in OFETs are investigated theoretically. The device structures explored resemble typical organic thin-film transistors with one of the channel contacts removed. By calculating the displacement current associated with charging and discharging of the channel in these capacitors, transient effects on the carrier transport in OSCs may be studied. In terms of the relevant models it is shown that the non-linearity of the process plays a key role. The non-linearity arises in the simplest case from the fact that channel resistance varies during the charging and discharging phases. Traps can be introduced into the models and their effects examined in some detail. When carriers are injected into the device, a conducting channel is established with traps that are initially empty. Gradual filling of the traps then modifies the transport characteristics of the injected charge carriers. In contrast, dc measurements as they are typically performed to characterize the transport properties of organic semiconductor channels investigate a steady state with traps partially filled. Numerical and approximate analytical models of the formation of the conducting channel and the resulting displacement currents are presented. For the process of transient carrier extraction, it is shown that if the channel capacitance is partially or completely discharged through the channel

  13. Model of nanodegradation processes in electronic equipment of NPP Kozloduy

    International Nuclear Information System (INIS)

    J. Boucher Blvd, 1164 Sofia, BG (Bulgaria))" data-affiliation=" (Sofia University, Faculty of Physics, 5 J. Boucher Blvd, 1164 Sofia, BG (Bulgaria))" >Popov, A

    2014-01-01

    From the complex studies it was proof that the main degradation processes in the three groups of elements for the extended period of time are slow; do not lead to a hopping change in basic parameters and to catastrophic failures. This gives grounds to suggest a common diffusion model, which is limited to the following: -in electronic components containing a p-n junction, is performed diffusion of residual cooper atoms, that are accumulated in the area of a spatial charge under the influence of the electric field and the local temperature, creating micro-shunt regions; -in the contactor systems whose contact surfaces are made of metal alloys under the influence of increased temperature starts decomposition of a homogeneous alloy. Conditions are created for diffusion of individual atoms to the surface, micro-phases of homogeneous atoms are formed and modify the contact resistances; -in the course of time in the insulating materials are changed the mechanisms of polarization, double bonds and dipoles are disrupting, leading to the release of carbon atoms. The latter diffuse at elevated temperatures and form conductive cords, which amend the dielectric losses and the specific resistance of the materials

  14. Model of nanodegradation processes in electronic equipment of NPP Kozloduy

    Science.gov (United States)

    Popov, A.

    2014-12-01

    From the complex studies it was proof that the main degradation processes in the three groups of elements for the extended period of time are slow; do not lead to a hopping change in basic parameters and to catastrophic failures. This gives grounds to suggest a common diffusion model, which is limited to the following: -in electronic components containing a p-n junction, is performed diffusion of residual cooper atoms, that are accumulated in the area of a spatial charge under the influence of the electric field and the local temperature, creating micro-shunt regions; -in the contactor systems whose contact surfaces are made of metal alloys under the influence of increased temperature starts decomposition of a homogeneous alloy. Conditions are created for diffusion of individual atoms to the surface, micro-phases of homogeneous atoms are formed and modify the contact resistances; -in the course of time in the insulating materials are changed the mechanisms of polarization, double bonds and dipoles are disrupting, leading to the release of carbon atoms. The latter diffuse at elevated temperatures and form conductive cords, which amend the dielectric losses and the specific resistance of the materials.

  15. Western diet enhances benzo(a)pyrene-induced colon tumorigenesis in a polyposis in rat coli (PIRC) rat model of colon cancer.

    Science.gov (United States)

    Harris, Kelly L; Pulliam, Stephanie R; Okoro, Emmanuel; Guo, Zhongmao; Washington, Mary K; Adunyah, Samuel E; Amos-Landgraf, James M; Ramesh, Aramandla

    2016-05-17

    Consumption of Western diet (WD), contaminated with environmental toxicants, has been implicated as one of the risk factors for sporadic colon cancer. Our earlier studies using a mouse model revealed that compared to unsaturated dietary fat, the saturated dietary fat exacerbated the development of colon tumors caused by B(a)P. The objective of this study was to study how WD potentiates B(a)P-induced colon carcinogenesis in the adult male rats that carry a mutation in the Apc locus - the polyposis in the rat colon (PIRC) rats. Groups of PIRC rats were fed with AIN-76A standard diet (RD) or Western diet (WD) and received 25, 50, or 100 μg B(a)P/kg body weight (wt) via oral gavage for 60 days. Subsequent to exposure, rats were euthanized; colons were retrieved and preserved in 10% formalin for counting the polyp numbers, measuring the polyp size, and histological analyses. Blood samples were collected and concentrations of cholesterol, triglycerides, glucose, insulin and leptin were measured. Rats that received WD + B(a)P showed increased levels of cholesterol, triglycerides, and leptin in comparison to RD + B(a)P groups or controls. The colon tumor numbers showed a B(a)P dose-response relationship. Adenomas with high grade dysplasia were prominent in B(a)P + WD rats compared to B(a)P + RD rats and controls (p diet - toxicant interactions in sporadic colon tumor development.

  16. 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...

  17. Increased numbers of orexin/hypocretin neurons in a genetic rat depression model

    DEFF Research Database (Denmark)

    Mikrouli, Elli; Wörtwein, Gitta; Soylu, Rana

    2011-01-01

    The Flinders Sensitive Line (FSL) rat is a genetic animal model of depression that displays characteristics similar to those of depressed patients including lower body weight, decreased appetite and reduced REM sleep latency. Hypothalamic neuropeptides such as orexin/hypocretin, melanin-concentra......The Flinders Sensitive Line (FSL) rat is a genetic animal model of depression that displays characteristics similar to those of depressed patients including lower body weight, decreased appetite and reduced REM sleep latency. Hypothalamic neuropeptides such as orexin/hypocretin, melanin...

  18. Model of charge-state distributions for electron cyclotron resonance ion source plasmas

    Directory of Open Access Journals (Sweden)

    D. H. Edgell

    1999-12-01

    Full Text Available A computer model for the ion charge-state distribution (CSD in an electron cyclotron resonance ion source (ECRIS plasma is presented that incorporates non-Maxwellian distribution functions, multiple atomic species, and ion confinement due to the ambipolar potential well that arises from confinement of the electron cyclotron resonance (ECR heated electrons. Atomic processes incorporated into the model include multiple ionization and multiple charge exchange with rate coefficients calculated for non-Maxwellian electron distributions. The electron distribution function is calculated using a Fokker-Planck code with an ECR heating term. This eliminates the electron temperature as an arbitrary user input. The model produces results that are a good match to CSD data from the ANL-ECRII ECRIS. Extending the model to 1D axial will also allow the model to determine the plasma and electrostatic potential profiles, further eliminating arbitrary user input to the model.

  19. 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.

  20. 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.

  1. Auditory evoked potentials in a newborn Wistar rat model of hyperbilirubinemia.

    Science.gov (United States)

    Gökdoğan, Çağıl; Genç, Aydan; Gülbahar, Özlem; Gökdoğan, Ozan; Helvacı, Ayşe; Bezgin, Selin Üstün; Memiş, Leyla

    2016-01-01

    Hyperbilirubinemia is a common health problem in newborns. Its effects can be different according to the level and duration of the hyperbilirubinemia. The toxic effect of bilirubin on the auditory system can be seen as a sensory neural hearing loss or auditory neuropathy spectrum disorder (ANSD). The purpose of our study was to determine the effects of toxic bilirubin level on the auditory system by using Auditory Brainstem Response audiometry. Rats are used as animal models due to their low cost and easy attainability. Auditory Brainstem Response was used for auditory assessment. In this study, three groups were established: experimental, control and placebo groups. In the experimental group, which consists of rats with hyperbilirubinemia, sensory neural hearing loss was found bilaterally in 4 rats (66.67%) and unilaterally in 2 rats (16.67%) and auditory neuropathy spectrum disorder was found unilaterally in 1 rat (8.33%). Auditory Brainstem Response thresholds were significantly elevated compared to control and placebo groups (p<0.05). Hyperbilirubinemia of newborn rats may result both in sensory neural hearing loss and auditory neuropathy spectrum disorder. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  2. Auditory evoked potentials in a newborn Wistar rat model of hyperbilirubinemia

    Directory of Open Access Journals (Sweden)

    Çagil Gökdogan

    2016-04-01

    Full Text Available ABSTRACT INTRODUCTION: Hyperbilirubinemia is a common health problem in newborns. Its effects can be different according to the level and duration of the hyperbilirubinemia. The toxic effect of bilirubin on the auditory system can be seen as a sensory neural hearing loss or auditory neuropathy spectrum disorder (ANSD. OBJECTIVE: The purpose of our study was to determine the effects of toxic bilirubin level on the auditory system by using Auditory Brainstem Response audiometry. METHODS: Rats are used as animal models due to their low cost and easy attainability. Auditory Brainstem Response was used for auditory assessment. In this study, three groups were established: experimental, control and placebo groups. RESULTS: In the experimental group, which consists of rats with hyperbilirubinemia, sensory neural hearing loss was found bilaterally in 4 rats (66.67% and unilaterally in 2 rats (16.67% and auditory neuropathy spectrum disorder was found unilaterally in 1 rat (8.33%. Auditory Brainstem Response thresholds were significantly elevated compared to control and placebo groups (p < 0.05. CONCLUSION: Hyperbilirubinemia of newborn rats may result both in sensory neural hearing loss and auditory neuropathy spectrum disorder.

  3. 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.

  4. Sensory and motor characterization in the postnatal valproate rat model of autism.

    Science.gov (United States)

    Reynolds, Stacey; Millette, Alexandre; Devine, Darragh P

    2012-01-01

    Although autism is diagnosed according to three core features of social deficits, communication impairments, and repetitive or stereotyped behaviors, other behavioral features such as sensory and motor impairments are present in more than 70% of individuals with autism spectrum disorders (ASD). Exposure of rat pups to the teratogen valproate during sensitive periods of brain development has been shown to elicit behavioral features associated with autism diagnosis and has been proposed as a valid animal model of the disorder. The purpose of this study was to characterize sensory and motor performance in rats postnatally treated with valproate. Thirty-four rat pups were injected with either valproate (150 mg/kg) or saline on postnatal days 6-12. Auditory and tactile startle as well as auditory sensory gating was assessed during both the juvenile and adolescent stages of development; motor testing was conducted during late adolescence and included a sunflower seed eating task and a vermicelli handling task. Valproate-treated rats were underresponsive to auditory stimuli, showed deficits in auditory sensory gating, and demonstrated impairments in motor speed and performance. These findings suggest that postnatal valproate treatment elicits sensory and motor features often seen in individuals with ASD. Further, the hyposensitivity seen in postnatally valproate-treated rats contrasted with hypersensitivity previously reported in prenatally valproate-exposed rats. This suggests that timing of teratogenic exposure during early brain development may be important to consider when investigating the neurobiological basis of sensorimotor impairments in ASD. Copyright © 2012 S. Karger AG, Basel.

  5. Genotypic and phenotypic characterization of P23H line 1 rat model.

    Directory of Open Access Journals (Sweden)

    Elise Orhan

    Full Text Available Rod-cone dystrophy, also known as retinitis pigmentosa (RP, is the most common inherited degenerative photoreceptor disease, for which no therapy is currently available. The P23H rat is one of the most commonly used autosomal dominant RP models. It has been created by incorporation of a mutated mouse rhodopsin (Rho transgene in the wild-type (WT Sprague Dawley rat. Detailed genetic characterization of this transgenic animal has however never been fully reported. Here we filled this knowledge gap on P23H Line 1 rat (P23H-1 and provide additional phenotypic information applying non-invasive and state-of-the-art in vivo techniques that are relevant for preclinical therapeutic evaluations. Transgene sequence was analyzed by Sanger sequencing. Using quantitative PCR, transgene copy number was calculated and its expression measured in retinal tissue. Full field electroretinography (ERG and spectral domain optical coherence tomography (SD-OCT were performed at 1-, 2-, 3- and 6-months of age. Sanger sequencing revealed that P23H-1 rat carries the mutated mouse genomic Rho sequence from the promoter to the 3' UTR. Transgene copy numbers were estimated at 9 and 18 copies in the hemizygous and homozygous rats respectively. In 1-month-old hemizygous P23H-1 rats, transgene expression represented 43% of all Rho expressed alleles. ERG showed a progressive rod-cone dysfunction peaking at 6 months-of-age. SD-OCT confirmed a progressive thinning of the photoreceptor cell layer leading to the disappearance of the outer retina by 6 months with additional morphological changes in the inner retinal cell layers in hemizygous P23H-1 rats. These results provide precise genotypic information of the P23H-1 rat with additional phenotypic characterization that will serve basis for therapeutic interventions, especially for those aiming at gene editing.

  6. 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

  7. 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

  8. 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.

  9. Cervical intervertebral disc degeneration induced by unbalanced dynamic and static forces: a novel in vivo rat model.

    Science.gov (United States)

    Wang, Yong-Jun; Shi, Qi; Lu, W W; Cheung, K C M; Darowish, Michael; Li, Tian-Fang; Dong, Yu-Feng; Zhou, Chong-Jian; Zhou, Quan; Hu, Zhi-Jun; Liu, Mei; Bian, Qin; Li, Chen-Guang; Luk, K D K; Leong, J C Y

    2006-06-15

    Establishment of a novel in vivo animal model of cervical spondylosis. To investigate apoptotic, degenerative, and inflammatory changes occurring in the cervical intervertebral discs of rats. Cervical degeneration occurs as the result of imbalance of both static and dynamic spinal stabilizers. The disc degeneration that occurs is characterized by increased local inflammation and increased apoptosis of intervertebral disc cells. By excising the paraspinal musculature and posterior cervical spinal ligaments of rats, both static and dynamic cervical stabilizers were disrupted. The resultant biomechanical imbalance resulted in biochemical and histologic changes, which were characterized by light microscopy, electron microscopy, immunostaining, enzyme-linked immunosorbent assay, polymerase chain reaction, and in situ hybridization. Histologic analysis showed characteristic degenerative changes of the intervertebral discs and vertebral endplates following surgery. Ultrastructural examination revealed apoptotic changes, which were verified by immunostaining. Instability also resulted in significant up-regulation of inflammatory factors, as shown by enzyme-linked immunosorbent assay, polymerase chain reaction, and in situ hybridization. By creating static and dynamic posterior instability of the cervical spine, this novel model of cervical spondylosis results in rapid intervertebral disc degeneration characterized by increased apoptosis and local inflammation, such as that seen clinically.

  10. Test of theoretical models for ultrafast heterogeneous electron ...

    Indian Academy of Sciences (India)

    Administrator

    (UHV) chambers, each equipped with a load-lock port, were employed for preparing and characteriz- ing the samples. A mobile UHV chamber served as the shuttle ..... there is no automatic transition to adiabatic electron transfer for high electronic coupling strength and the excitation of high energy vibrational modes can not.

  11. Developing Argumentation Strategies in Electronic Dialogs: Is Modeling Effective?

    Science.gov (United States)

    Mayweg-Paus, Elisabeth; Macagno, Fabrizio; Kuhn, Deanna

    2016-01-01

    The study presented here examines how interacting with a more capable interlocutor influences use of argumentation strategies in electronic discourse. To address this question, 54 young adolescents participating in an intervention centered on electronic peer dialogs were randomly assigned to either an experimental or control condition. In both…

  12. Dynamic examination of the femur in a rat model of osteoporosis after injection of CPC containing ABK and PLLA

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, A.; Kusaka, T.; Sasaki, S.; Takano, I.; Tahara, Y.; Ishii, Y. [Kyorin Univ. School of Medicine, Tokyo (Japan). Dept. of Orthopaedic Surgery

    2001-07-01

    We developed calcium phosphate cement containing antibiotics and poly lactic acid, and examined the effects on bone strength by injecting the cement into the medullary space of the femur in model rats with osteoporosis. A good strength of bone was obtained over 6 months by injecting bone paste into the medullary space of the femur in model rats with bone formation. (orig.)

  13. The rat as a model for orthodontic tooth movement--a critical review and a proposed solution.

    NARCIS (Netherlands)

    Ren, Y.; Maltha, J.C.; Kuijpers-Jagtman, A.M.

    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

  14. 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

  15. Electron kinetics modeling in a weakly ionized gas

    International Nuclear Information System (INIS)

    Boeuf, Jean-Pierre

    1985-01-01

    This work presents some features of electron kinetics in a weakly ionized gas. After a summary of the basis and recent developments of the kinetic theory, and a review of the most efficient numerical techniques for solving the Boltzmann equation, several aspects of electron motion in gases are analysed. Relaxation phenomena toward equilibrium under a uniform electric field, and the question of the existence of the hydrodynamic regime are first studied. The coupling between electron kinetics and chemical kinetics due to second kind collisions in Nitrogen is then analysed; a quantitative description of the evolution of the energy balance, accounting for electron-molecule as well as molecule-molecule energy transfer is also given. Finally, electron kinetics in space charge distorted, highly non uniform electric fields (glow discharges, streamers propagation) is investigated with microscopic numerical methods based on Boltzmann and Poisson equations. (author) [fr

  16. The improved DGR analytical model of electron density height profile and total electron content in the ionosphere

    OpenAIRE

    Radicella, S. M.; Zhang, M. L.

    1995-01-01

    Tests of the analytical model of the electron density profile originally proposed by G, Di Giovanni and S.M. Radicella (DGR model) have shown the need to introduce improvements in order to obtain a model able to reproduce the ionosphere in a larger spectrum of geophysical and time conditions. The present paper reviews the steps toward such progress and presents the final formulation of the model. It gives also a brief re- view of tests of the improved model done by different authors.

  17. [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 (Prats of maximum rPTH(1-84) injection group (160 µg/kg) were higher than those of normal control group (Prats treated with calcitriol had normal calcium levels and showed the increase of BMD and phosphorus

  18. Freshly isolated hepatocyte transplantation in acetaminophen-induced hepatotoxicity model in rats

    Directory of Open Access Journals (Sweden)

    Daniela Rodrigues

    2012-12-01

    Full Text Available CONTEXT: Hepatocyte transplantation is an attractive therapeutic modality for liver disease as an alternative for orthotopic liver transplantation. OBJECTIVE: The aim of the current study was to investigate the feasibility of freshly isolated rat hepatocyte transplantation in acetaminophen-induced hepatotoxicity model. METHODS: Hepatocytes were isolated from male Wistar rats and transplanted 24 hours after acetaminophen administration in female recipients. Female rats received either 1x10(7 hepatocytes or phosphate buffered saline through the portal vein or into the spleen and were sacrificed after 48 hours. RESULTS: Alanine aminotransferase levels measured within the experiment did not differ between groups at any time point. Molecular analysis and histology showed presence of hepatocytes in liver of transplanted animals injected either through portal vein or spleen. CONCLUSION: These data demonstrate the feasibility and efficacy of hepatocyte transplantation in the liver or spleen in a mild acetaminophen-induced hepatotoxicity model.

  19. 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.

  20. Cardiovascular and hormonal (aldosterone) responses in a rat model which mimics responses to weightlessness

    Science.gov (United States)

    Musacchia, X. J.; Steffen, J. M.

    1984-01-01

    Cardiovascular responses and fluid/electrolyte shifts seen during spaceflight have been attributed to cephalad redistribution of vascular fluid. The antiorthostatic (AO) rat (suspended, head-down tilt of 15-20 deg) is used to model these responses. This study documents that elevated blood pressures in AO rats are sustained for periods of up to seven days, compared with presuspension values. Increased blood pressures in AO rats suggests a specific response to AO positioning, potentially relatable to a cephalad fluid shift. To assess a role for hormonal regulation of sodium excretion, serum aldosterone levels were measured. Circulating aldosterone concentrations were seen to increase approximately 100 percent during seven days of AO suspension, concurrently with a pronounced natriuresis. These results suggest that aldosterone may not be involved in the long term regulation of increased Na(+) excretion in AO animals. These studies continue to show the usefulness of models for the development of animal protocols for space flight.

  1. 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...

  2. Role of group 3 innate lymphoid cells during experimental otitis media in a rat model.

    Science.gov (United States)

    Cho, Chang Gun; Gong, Sung Ho; Kim, Hee-Bok; Song, Jae-Jun; Park, Joo Hyun; Lim, Yun-Sung; Park, Seok-Won

    2016-09-01

    The objective of this study was to evaluate the role of group 3 innate lymphoid cells (ILC3) in the middle ear (ME) mucosal response to bacterial infection in a rat model. To confirm the role of ILC3 in bacterially induced otitis media (OM), the serum concentrations of IL-17 and IL-22 were determined by ELISA, and the tissue expression of IL-17 and IL-22 in infected ME mucosa was assessed by immunohistochemical staining. Immunohistochemical staining of specific cell surface markers was also assessed to confirm the origin of the cells expressing IL-17 and IL-22. Twenty Sprague-Dawley rats were used in the surgically-induced animal model of OM. OM was induced by inoculation of non-typeable Haemophilus influenzae into the ME cavity of the rats. The rats were divided into four experimental groups: three infected groups and one control group. Infected groups were subdivided into sets of 5 rats, one for each of the three time points (1, 4 and 7 days post-inoculation). For determination of rat IL-17 and IL-22 levels in infected rats and control rats, infected or control ME mucosa sections were analyzed by immunohistochemistry with specific antibodies directed against IL-17 and IL-22. Immunohistochemical staining for CD3, RORγt, and NKp46 were also conducted on the samples to confirm the origin of cells expressing IL-17 and IL-22. IL-17 and IL-22 serum concentrations were significantly increased in the infected rats compared to control rats. Immunohistochemical staining revealed increased IL-17 and IL-22 expressions in all infected ME mucosae from the first day after inoculation. In addition, the results of tissue staining for the specific surface markers were negative for CD3 and NKp46, but were highly positive for RORγt. IL-17 and IL-22 revealed their association with the bacterially induced proliferative and hyperplastic responses of ME mucosa, which are characteristic features in pathogenesis of OM. Surface marker examination showed that the source cells for IL-17

  3. 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

  4. Susceptibility and Phase Transitions in the Pseudospin-Electron Model at Weak Coupling

    International Nuclear Information System (INIS)

    Stasyuk, I.V.; Mysakovych, T.S.

    2003-01-01

    The pseudospin-electron model (PEM) is considered in the case of the weak pseudospin-electron coupling. It is shown that the transition to uniform and chess-board phases occurs when the chemical potential is situated near the electron band edges and near the band centre, respectively. The incommensurate phase is realized at the intermediate values of the chemical potential. (author)

  5. 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.

  6. The effect of captopril on endometriotic implants in a rat model.

    Science.gov (United States)

    Oktem, Mesut; Ozcan, Pinar; Erdem, Ozlem; Karakaya, Cengiz; Cenksoy, Cahit; Guner, Haldun; Karabacak, Onur; Dursun, Polat

    2014-09-01

    To determine the effects of captopril on experimentally induced endometriosis in a rat model. Twenty-four adult, mature female Wistar-Albino rats in which endometriotic implants were induced by transplanting autologous uterine tissue to ectopic sites on the peritoneum. After the endometriotic implants were formed surgically, the 24 rats were randomly divided into three groups. Group 1 (captopril group, eight rats) were given 50 mg kg(-1)d(-1) of oral captopril for 21 d. Group 2 (leuprolide acetate group, eight rats) were given a single 1 mg kg(-1) subcutaneous injection of leuprolide acetate. Group 3 (control) were given no medication and served as controls (eight rats). The surface area of the endometriotic implants and the score of histologic analysis. Also, VEGF and MCP-1 levels in peritoneal fluids and bloods were analyzed. At the beginning of the medical treatment, the mean surface areas of the endometriotic implants were comparable in all three groups. At the end of the treatment the mean implant surface area in the captopril group and leuprolide acetate group was less than that in the control group. Mean histopathological examination score for the implants post treatment was lower in the captopril and leuprolide acetate groups. Peritoneal fluids VEGF level in the captopril and leuprolide acetate groups was lower than that in the control group. The post-treatment MCP-1 level was also lower in the captopril and leuprolide acetate groups than in the control group. The serum VEGF and MCP-1 levels post treatment were significantly lower in the captopril and leuprolide acetate groups than in the control group. Administration of captopril reduced the size and progression of endometriotic lesions in a rat model. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  7. Motor hyperactivity of the iron-deficient rat - an animal model of restless legs syndrome.

    Science.gov (United States)

    Lai, Yuan-Yang; Cheng, Yu-Hsuan; Hsieh, Kung-Chiao; Nguyen, Darian; Chew, Keng-Tee; Ramanathan, Lalini; Siegel, Jerome M

    2017-12-01

    Abnormal striatal dopamine transmission has been hypothesized to cause restless legs syndrome. Dopaminergic drugs are commonly used to treat restless legs syndrome. However, they cause adverse effects with long-term use. An animal model would allow the systematic testing of potential therapeutic drugs. A high prevalence of restless legs syndrome has been reported in iron-deficient anemic patients. We hypothesized that the iron-deficient animal would exhibit signs similar to those in restless legs syndrome patients. After baseline polysomnographic recordings, iron-deficient rats received pramipexole injection. Then, iron-deficient rats were fed a standard rodent diet, and polysomnographic recording were performed for 2 days each week for 4 weeks. Iron-deficient rats have low hematocrit levels and show signs of restless legs syndrome: sleep fragmentation and periodic leg movements in wake and in slow-wave sleep. Iron-deficient rats had a positive response to pramipexole treatment. After the iron-deficient rats were fed the standard rodent diet, hematocrit returned to normal levels, and sleep quality improved, with increased average duration of wake and slow-wave sleep episodes. Periodic leg movements decreased during both waking and sleep. Hematocrit levels positively correlated with the average duration of episodes in wake and in slow-wave sleep and negatively correlated with periodic leg movements in wake and in sleep. Western blot analysis showed that striatal dopamine transporter levels were higher in iron-deficient rats. The iron-deficient rat is a useful animal model of iron-deficient anemic restless legs syndrome. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society.

  8. Impaired decision making and loss of inhibitory-control in a rat model of Huntington disease

    Directory of Open Access Journals (Sweden)

    Nicole El Massioui

    2016-10-01

    Full Text Available Cognitive deficits associated with Huntington disease (HD are generally dominated by executive function disorders often associated with disinhibition and impulsivity/compulsivity. Few studies have directly examined symptoms and consequences of behavioral disinhibition in HD and its relation with decision-making. To assess the different forms of impulsivity in a transgenic model of HD (tgHD rats, two tasks assessing cognitive/choice impulsivity were used: risky decision-making with a Rat Gambling Task (RGT and intertemporal choices with a delay discounting task (DD. To assess waiting or action impulsivity the differential reinforcement of low rate of responding task (DRL was used. In parallel, the volume as well as cellular activity of the amygdala was analyzed. In contrast to WT rats, 15 months old tgHD rats exhibited a poor efficiency in the RGT task with difficulties to choose advantageous options, a steep delay discounting curve as delays increased in the DD task and a high rate of premature and bursts responses in the DRL task. tgHD rats also demonstrated a simultaneous and correlated presence of both action and cognitive/choice impulsivity in contrast to WT animals. Moreover, a reduced volume associated with an increased basal cellular activity of the central nucleus of amygdala indicated a dysfunctional amygdala in tgHD rats, which could underlie inhibitory dyscontrol. In conclusion, tgHD rats are a good model for impulsivity disorder that could be used more widely to identify potential pharmacotherapies to treat these invasive symptoms in HD.

  9. 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.

  10. Slow electron energy balance for hybrid models of direct-current glow discharges

    Science.gov (United States)

    Eliseev, S. I.; Bogdanov, E. A.; Kudryavtsev, A. A.

    2017-09-01

    In this paper, we present the formulation of slow electron energy balance for hybrid models of direct current (DC) glow discharge. Electrons originating from non-local ionization (secondary) contribute significantly to the energy balance of slow electrons. An approach towards calculating effective energy brought by a secondary electron to the group of slow electrons by means of Coulomb collisions is suggested. The value of effective energy shows a considerable dependence on external parameters of a discharge, such as gas pressure, type, and geometric parameters. The slow electron energy balance was implemented into a simple hybrid model that uses analytical formulation for the description of non-local ionization by fast electrons. Simulations of short (without positive column) DC glow discharge in argon are carried out for a range of gas pressures. Comparison with experimental data showed generally good agreement in terms of current-voltage characteristics, electron density, and electron temperature. Simulations also capture the trend of increasing electron density with decreasing pressure observed in the experiment. Analysis shows that for considered conditions, the product of maximum electron density ne and electron temperature Te in negative glow is independent of gas pressure and depends on the gas type, cathode material, and discharge current. Decreasing gas pressure reduces the heating rate of slow electrons during Coulomb collisions with secondary electrons, which leads to lower values of Te and, in turn, higher maximum ne.

  11. Diagnostic PET Imaging of Mammary Microcalcifications Using64Cu-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

  12. 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.

  13. Effect of erythropoietin on intestinal injury and bacterial translocation in neonatal rat model of necrotizing enterocolitis

    Directory of Open Access Journals (Sweden)

    Xiao-qing CHEN

    2012-05-01

    Full Text Available Objective  To observe the influence of erythropoietin (EPO on intestinal histopathological changes and bacterial translocation (BT in neonatal rat model of necrotizing enterocolitis (NEC, and explore the protective effect of EPO against NEC. Methods  Seventy-five three-day-old SD rat pups were randomly divided into three groups (25 in each group: normal control group, NEC model group and EPO intervention group. The rat pups in normal control group were placed together with their mothers and breast fed, receiving no other intervention. NEC model group rats were separated from their mothers, housed in an incubator, and gavaged with rat-milk substitute, then experienced hypoxia (breathing 100% nitrogen gas for 90s and cold stress (4℃ for 10min three times daily for 3 days. EPO intervention group rats were fed with the substitute of rat-milk supplemented with 0.1U/ml of EPO, and they were also given hypoxia and cold stress similar to that of the NEC model group. Blood samples were obtained via cardiac puncture, and 2-cm-length of terminal ileum proximal to the ileocecal valve were obtained from the animals on the 4th day. The histopathological changes in terminal ileum were scored after hematoxylin-eosin (HE staining, and the scores ≥2 were defined as NEC. To determine the incidence of bacterial translocation, 16S rRNA real-time fluorescence quantitative PCR was used to detect the bacterial DNA in blood samples. Results  Compared with the NEC model group, the mean rank-sum rate of the intestinal histopathological score (39.4583 vs 53.8696, NEC incidence [25%(6/24 vs 57%(13/23] and bacterial translocation rate [17% (4/24 vs 65%(15/23] in EPO intervention group were significantly lowered (P < 0.05, P < 0.01. Conclusion  Enteral EPO administration is not only effective for reduction of the severity and incidence of NEC, but also for decrease of the bacterial translocation rate in neonatal rat models.

  14. 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.

  15. 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.

  16. Use of decorin to prevent epidural fibrosis in a post-laminectomy rat model.

    Science.gov (United States)

    Turkoglu, Erhan; Dinc, Cem; Tuncer, Cengiz; Oktay, Murat; Serbes, Gokhan; Sekerci, Zeki

    2014-02-05

    The formation of epidural fibrosis adjacent to the dura mater is a complex multi-step process that is associated with a marked reduction in tissue cellularity and the excessive deposition of extracellular matrix components. Extensive epidural fibrosis is a major cause of post-laminectomy syndrome. Decorin strongly inhibits fibrosis formation in various tissues via blockade of transforming growth factor-β1. The aim of this study was to investigate the effects of a topical application of decorin on the formation of epidural fibrosis in a rat laminectomy model. Twenty-four female Wistar albino rats (250-350 g) were equally and randomly divided into three groups (control, spongostan and decorin). Laminectomy was performed between the L3 and L5 levels in all rats. The dura mater was directly exposed to spongostan soaked with saline (2 cc/kg) or decorin (100 µg/kg). Four weeks later, the laminectomized spine of the rats was completely removed between the L3 and L5 levels. The extent of the epidural fibrosis and arachnoidal involvement was histopathologically evaluated and graded. Our data revealed that epidural fibrosis was significantly reduced in the group treated with decorin compared to the spongostan and control groups (Plaminectomy rat model. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. 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

  18. 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.

  19. 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

  20. 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.

  1. Challenges of 4D(ata Model for Electronic Government

    Directory of Open Access Journals (Sweden)

    Bogdan GHILIC-MICU

    2015-01-01

    Full Text Available Social evolution pyramid, built on the foundation of the ‘90s capitalist society, lead to the emergence of the informational society – years 1990 to 2005 – and knowledge society – years 2005 to 2020. The literature starts using a new concept, a new form of association – artificial intelligence society – foreseen to be established in the next time frame. All these developments of human society and translations or leaps (most of the times apparently timeless were, are and will be possible only due to the advancing information and communications technologies. The leap to Democracy 3.0, based on information and communication technologies prompts to a radical change in the majority of the classical concepts targeting society structure and the way it is guided and controlled. Thus, concepts become electronic concepts (or e-concepts through the use of new technologies. E-concepts keep the essence of the classical principles of liberty and democracy, adding a major aspect of the new way of communication and spreading ideas between people. The main problem is to quantify, analyze and foresee the way technological changes will influence not only the economic system, but also the daily life of the individual and the society. Unfortunately (or maybe fortunately, depending on the point of view, all these evolutions and technological and social developments are as many challenges for the governments of the world. In this paper we will highlight only four of the challenges facing the governments, grouped in a structured model with the following specific concepts: Big Data, Social Data, Linked Data and Mobile Data. This is an emerging paradigm of the information and communication technology supporting national and global eGovernment projects.

  2. A two-state stochastic model of REM sleep architecture in the rat.

    Science.gov (United States)

    Gregory, Gavin G; Cabeza, Rafael

    2002-11-01

    Rapid eye movement (REM) sleep is a recurring state throughout the sleeping period. Based on the examination of 45 sleep records of 3-mo-old male rats during the middle of the light phase, a stochastic model is proposed for the sequence X(1),Y(2), X(2),Y(2),. of REM sleep durations X and inter-REM sleep waiting times Y experienced by a rat during a sleeping period. In our model the probability distribution of any variable in the sequence, given the past, is allowed to depend on only the immediately previous variable. The conditional distributions f(y(i) | x(i)) and g(x(i+1) | y(i)) do not depend on the index i. It is shown that the marginal distributions tend to stationarity. Aggregations of the data on a discrete time scale suggest that the conditional distributions be formulated as two-component mixtures. These component distributions are modeled as Poisson and their means are called the means of short and long waiting time and the means of short and long REM sleep duration. Associated with each mean is a probability weight. Parametric forms are given to the means and probability weights. The model estimated by maximum likelihood shows a good fit to data of the 3-mo-old rats. The model fit to a smaller data set obtained from rats aged 15-22 mo shows a significant shortening of the means for both short and long REM sleep bout durations compared with the means of the 3-mo-old rats. Neuronal correlates for the behavior of the model are discussed in the context of the reciprocal interaction model of REM sleep regulation.

  3. 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

  4. A new theoretical model for scattering of electrons by molecules. 1

    International Nuclear Information System (INIS)

    Peixoto, E.M.A.; Mu-tao, L.; Nogueira, J.C.

    1975-01-01

    A new theoretical model for electron-molecule scattering is suggested. The e-H 2 scattering is studied and the superiority of the new model over the commonly used Independent Atom Model (IAM) is demonstrated. Comparing theoretical and experimental data for 40keV electrons scattered by H 2 utilizing the new model, its validity is proved, while Partial Wave and First Born calculations, employing the Independent Atom Model, strongly deviated from the experiment [pt

  5. Retrograde amnesia produced by electron beam exposure: causal parameters and duration of memory loss. [Rats

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, T.G.; Hardy, K.A.

    1985-01-01

    The production of retrograde amnesia (RA) upon electron beam exposure has been investigated. RA production was evaluated using a single-trial avoidance task across a 10/sup 4/ dose range for 10-, 1-, and 0.1-..mu..sec pulsed exposures. The dose-response curve obtained at each pulse duration showed significant RA production. The most effective dose range was 0.1-10 rad at a dose rate of 10/sup 6/ rad/sec. By employing a 10 rad (10/sup 6/ rad/sec) pulse, a memory loss of the events occurring in the previous 4 sec was demonstrated. The conclusion was that the RA effect might be due to sensory activation which provided a novel stimulus that masked previous stimuli.

  6. 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

  7. Estradiol does not affect spasms in the betamethasone-NMDA rat model of infantile spasms.

    Science.gov (United States)

    Chachua, Tamar; Di Grazia, Paola; Chern, Chian-Ru; Johnkutty, Meenu; Hellman, Benjamin; Lau, Ho An; Shakil, Faariah; Daniel, Margaret; Goletiani, Cezar; Velíšková, Jana; Velíšek, Libor

    2016-08-01

    This study attempted to validate the effects of neonatal estradiol in ameliorating the spasms in the prenatally betamethasone-primed N-methyl-d-aspartate (NMDA) model of infantile spasms in rats as shown previously in a mouse Arx gene knock-in expansion model of infantile spasms. Neonatal rats prenatally exposed to betamethasone (on day 15 of pregnancy) were treated with subcutaneous 40 ng/g estradiol benzoate (EB) between postnatal days (P)3-P10 or P0-P5. A synthetic estrogen analogue, diethylstilbestrol, was used between P0 and P5 (2 μg per rat, s.c.). On P12, P13, and P15, the rats were subjected to NMDA-triggered spasms, and latency to onset and number of spasms were evaluated. Rats with EB on P3-P10 were tested after spasms in the open field, novel object recognition, and elevated plus maze to determine effects of treatment on behavior. Additional rats with P3-P10 or P0-P5 EB were investigated for γ-aminobutyric acid (GABA)ergic neurons (glutamate decarboxylase [GAD]67 expression) in the neocortex. As a positive control, a group of rats received either subcutaneous adrenocorticotropic hormone (ACTH) (2 × 0.3 mg/kg on P12 and 3 × 0.3 mg/kg on P13 and P14) or vehicle after the first episode of spasms on P12. Neither EB treatment nor diethylstilbestrol consistently affected expression of spasms in this model, although we found a significant increase in GAD67-immunopositive cells in the neocortex after P3-P10 and P0-P5 EB treatment, consistent with a study in mice. Behavioral tests showed increase in lateralization in male rats treated with P3-P10 EB, a behavioral trait usually associated with female sex. Diethylstilbestrol treatment in male rats resulted in arrested pubertal descent of testes. ACTH had robust effects in suppressing spasms. Treatment of infantile spasms (IS) using neonatal EB may be justified in those cases of IS that present with detectable deficits in GABAergic neurons. In other types of IS, the efficacy of neonatal EB and its analogues is

  8. EDUCATIONAL COMPLEX ON ELECTRICAL ENGINEERING AND ELECTRONICS BASED ON MODELING IN PROGRAM TINA

    Directory of Open Access Journals (Sweden)

    Vladimir A. Alekhin

    2014-01-01

    Full Text Available The educational complex on the electrical engineering and electronics has been developed. It contains a course of lectures and lecture notes in the electronic form, a new computer laboratory practical work and practical training. All electronic manuals are based on modeling of electric and electronic circuits in the new effective program TINA. The educational complex is being successfully used in educational process on internal and distant learning. 

  9. Effects of hydrogen-rich water on abnormalities in a SHR.Cg-Leprcp/NDmcr rat - a metabolic syndrome rat model

    OpenAIRE

    Hashimoto Michio; Katakura Masanori; Nabika Toru; Tanabe Yoko; Hossain Shahdat; Tsuchikura Satoru; Shido Osamu

    2011-01-01

    Abstract Background Hydrogen (H2), a potent free radical scavenger, selectively reduces the hydroxyl radical, which is the most cytotoxic of the reactive oxygen species (ROS). An increase in oxygen free radicals induces oxidative stress, which is known to be involved in the development of metabolic syndrome. Therefore, we investigated whether hydrogen-rich water (HRW) affects metabolic abnormalities in the metabolic syndrome rat model, SHR.Cg-Leprcp/NDmcr (SHR-cp). Methods Male SHR-cp rats (5...

  10. Cerebral markers of the serotonergic system in rat models of obesity and after Roux-en-Y gastric bypass

    DEFF Research Database (Denmark)

    Ratner, Cecilia; Ettrup, Anders; Bueter, Marco

    2012-01-01

    DIO as compared to pgDR rats corresponds to what is reported in overweight humans and suggests that the dysfunctions of the 5-HT system associated with overeating or propensity to become overweight are polygenically determined. Our results support that the obesity-prone rat model has high translational value......Food intake and body weight are regulated by a complex system of neural and hormonal signals, of which the anorexigenic neurotransmitter serotonin (5-hydroxytryptamine or 5-HT) is central. In this study, rat models of obesity and weight loss intervention were compared with regard to several 5-HT...... markers. Using receptor autoradiography, brain regional-densities of the serotonin transporter (SERT) and the 5-HT(2A) and 5-HT(4) receptors were measured in (i) selectively bred polygenic diet-induced obese (pgDIO) rats, (ii) outbred DIO rats, and (iii) Roux-en-Y gastric bypass (RYGB)-operated rats. pg...

  11. 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.

  12. 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)

  13. Electronic Modeling and Design for Extreme Temperatures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop electronics for operation at temperatures that range from -230oC to +130oC. This new technology will minimize the requirements for external...

  14. Electronic Modeling and Design for Extreme Temperatures, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop electronics for operation at temperatures that range from -230oC to +130oC. This new technology will minimize the requirements for external...

  15. New two-fluid (localized + band electron) model for manganites

    Indian Academy of Sciences (India)

    Two types of eg electronic states arise in doped manganites (due to strong JT coupling, strong U, filling conditions, …): Localized, with JT distortion, do not hop; Without distortion, hop and form a band ...

  16. Comparison of Goto-Kakizaki rats and high fat diet-induced obese rats: Are they reliable models to study Type 2 Diabetes mellitus?

    Directory of Open Access Journals (Sweden)

    Wilson Mitsuo Tatagiba Kuwabara

    Full Text Available Type 2 Diabetes mellitus (T2DM is an evident growing disease that affects different cultures throughout the world. T2DM occurs under the influence of three main factors: the genetic background, environmental and behavioral components. Obesity is strongly associated to the development of T2DM in the occident, while in the orient most of the diabetic patients are considered lean. Genetics may be a key factor in the development of T2DM in societies where obesity is not a recurrent public health problem. Herein, two different models of rats were used to understand their differences and reliability as experimental models to study the pathophysiology of T2DM, in two different approaches: the genetic (GK rats and the environmental (HFD-induced obese rats influences. GK rats were resistant to weight gain even though food/energy consumption (relative to body weight was higher in this group. HFD, on the other hand, induced obesity in Wistar rats. White adipose tissue (WAT expansion in this group was accompanied by immune cells infiltration, inflammation and insulin resistance. GK rats also presented WAT inflammation and insulin resistance; however, no immune cells infiltration was observed in the WAT of this group. Liver of HFD group presented fat accumulation without differences in inflammatory cytokines content, while liver of GK rats didn't present fat accumulation, but showed an increase of IL-6 and IL-10 content and glycogen. Also, GK rats showed increased plasma GOT and GPT. Soleus muscle of HFD presented normal insulin signaling, contrary to GK rats, which presented higher content of basal phosphorylation of GSK-3β. Our results demonstrated that HFD developed a mild insulin resistance in Wistar rats, but was not sufficient to develop T2DM. In contrast, GK rats presented all the typical hallmarks of T2DM, such as insulin resistance, defective insulin production, fasting hyperglycemia/hyperinsulinemia and lipid plasma alteration. Thus, on the given

  17. A Comparative Study of Spectral Auroral Intensity Predictions From Multiple Electron Transport Models

    Science.gov (United States)

    Grubbs, Guy; Michell, Robert; Samara, Marilia; Hampton, Donald; Hecht, James; Solomon, Stanley; Jahn, Jorg-Micha

    2018-01-01

    It is important to routinely examine and update models used to predict auroral emissions resulting from precipitating electrons in Earth's magnetotail. These models are commonly used to invert spectral auroral ground-based images to infer characteristics about incident electron populations when in situ measurements are unavailable. In this work, we examine and compare auroral emission intensities predicted by three commonly used electron transport models using varying electron population characteristics. We then compare model predictions to same-volume in situ electron measurements and ground-based imaging to qualitatively examine modeling prediction error. Initial comparisons showed differences in predictions by the GLobal airglOW (GLOW) model and the other transport models examined. Chemical reaction rates and radiative rates in GLOW were updated using recent publications, and predictions showed better agreement with the other models and the same-volume data, stressing that these rates are important to consider when modeling auroral processes. Predictions by each model exhibit similar behavior for varying atmospheric constants, energies, and energy fluxes. Same-volume electron data and images are highly correlated with predictions by each model, showing that these models can be used to accurately derive electron characteristics and ionospheric parameters based solely on multispectral optical imaging data.

  18. Electron injector for high-voltage model of collective accelerator

    International Nuclear Information System (INIS)

    Belikov, V.V.; Zvyagintsev, A.V.; Lymar', A.G.; Martynenko, P.A.; Khizhnyak, N.A.

    1987-01-01

    The design and test results of an electron gun with the beam compression and axial hole aimed at collective acceleration are presented. The electron gun is tested at 150 kV, the pulse duration being 12 ms. The hallow beam has 10 mm in diameter, with 1 mm thick wall, that corresponds to the compression degree of 200. The beam microperveance is 4.5 mA/V 3/2

  19. Pharmacokinetic/Pharmacodynamic Relationship of Gabapentin in a CFA-induced Inflammatory Hyperalgesia Rat Model

    DEFF Research Database (Denmark)

    Larsen, Malte Selch; Keizer, Ron; Munro, Gordon

    2016-01-01

    PURPOSE: Gabapentin displays non-linear drug disposition, which complicates dosing for optimal therapeutic effect. Thus, the current study was performed to elucidate the pharmacokinetic/pharmacodynamic (PKPD) relationship of gabapentin's effect on mechanical hypersensitivity in a rat model of CFA...... provides further knowledge into the understanding of gabapentin's non-linear pharmacokinetics and the link between plasma/brain disposition and anti-hyperalgesic effects. The model suggests that intestinal absorption is the primary source of non-linearity and that the investigated rat model provides......-induced inflammatory hyperalgesia. METHODS: A semi-mechanistic population-based PKPD model was developed using nonlinear mixed-effects modelling, based on gabapentin plasma and brain extracellular fluid (ECF) time-concentration data and measurements of CFA-evoked mechanical hyperalgesia following administration...

  20. 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

  1. 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: ...

  2. [Cardioprotective properties of zoniporide studied on experimental ischemia and reperfusion models in rat myocardium].

    Science.gov (United States)

    Gurova, N A; Spasov, A A; Timofeeva, A S; Zheltova, A A; Fedorchuk, V Iu

    2013-01-01

    Using the experimental model of rat heart ischemia/reperfusion, it is established that zoniporide (inhibitor of Na+/H+ exchanger) produces a significant (1.4-fold) decrease in the area of myocardial necrosis, 2.1-fold decrease in the serum troponin I level, and 2-fold decrease in the severity of post-reperfusion arrhythmias.

  3. RAT Selection and Resource Allocation in Heterogeneous Networks - OPNET Modeler in Optimization Studies

    DEFF Research Database (Denmark)

    Zakrzewska, Anna; Ruepp, Sarah Renée; Berger, Michael Stübert

    2013-01-01

    The paper addresses the problem of optimal selection of Radio Access Technology (RAT) and assignment of resources in a multistandard wireless network scenario. It is shown how OPNET Modeler can be used to perform optimization studies using Integer Linear Programming (ILP) solvers. In this way...

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

    African Journals Online (AJOL)

    1Department of Nephrology, Heping Hospital Affiliated to Changzhi Medical College, Changzhi, Shanxi 046000, 2Clinical. Medicine ... tubule swelling and expansion induced by adenine administration. Conclusion: ... administration in a rat model of CKD by inhibiting FGF-23, parathyroid hormone, and phosphate. Thus,.

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

    African Journals Online (AJOL)

    Department of Orthopaedics II, Ankang City Central Hospital, Ankang, Shanxi 725000, China. *For correspondence: Email: ... Purpose: To evaluate the activity of naringin (NAR) in a rat model of spinal cord ischemic injury (SCII). Methods: Forty female ... NAR administration effectively downregulated the protein expression of ...

  6. 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 ...

  7. Impaired coronary endothelial function in a rat model of spontaneous albuminuria

    NARCIS (Netherlands)

    Gschwend, Simone; Pinto-Sietsma, Sara-Joan; Buikema, Hendrik; Pinto, Yigal M.; van Gilst, Wiek H.; Schulz, Angela; de Zeeuw, Dick; Kreutz, Reinhold

    2002-01-01

    BACKGROUND: Albuminuria is an independent risk factor of coronary artery disease and has been proposed to reflect a general endothelial disorder. The Munich Wistar Frömter (MWF) rat strain develops spontaneous albuminuria and, therefore, may be an interesting experimental model to study alterations

  8. Effects of Ecballium elaterium on brain in a rat model of sepsis ...

    African Journals Online (AJOL)

    Here we examined the anti-inflammatory and antioxidant effects of Ecballium elaterium (EE) on brain, and explored its therapeutic potential in an animal model of sepsis-associated encephalopathy (SAE) [induced by cecal ligation and puncture (CLP)]. Thirty rats were divided into three groups of 10 each: control, sepsis, ...

  9. Assessing Autophagy in Sciatic Nerves of a Rat Model that Develops Inflammatory Autoimmune Peripheral Neuropathies

    Directory of Open Access Journals (Sweden)

    Susana Brun

    2017-09-01

    Full Text Available The rat sciatic nerve has attracted widespread attention as an excellent model system for studying autophagy alterations in peripheral neuropathies. In our laboratory, we have developed an original rat model, which we used currently in routine novel drug screening and to evaluate treatment strategies for chronic inflammatory demyelinating polyneuropathy (CIDP and other closely related diseases. Lewis rats injected with the S-palmitoylated P0(180-199 peptide develop a chronic, sometimes relapsing-remitting type of disease. Our model fulfills electrophysiological criteria of demyelination with axonal degeneration, confirmed by immunohistopathology and several typical features of CIDP. We have set up a series of techniques that led us to examine the failures of autophagy pathways in the sciatic nerve of these model rats and to follow the possible improvement of these defects after treatment. Based on these newly introduced methods, a novel area of investigation is now open and will allow us to more thoroughly examine important features of certain autophagy pathways occurring in sciatic nerves.

  10. 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

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

    African Journals Online (AJOL)

    Purpose: To investigate the preventive effect of resveratrol against renal pathological changes in a rat model of chronic kidney disease (CKD). Methods: CKD was induced by daily intragastric administration of adenine (200 mg/kg) for 1 month. The effect of 10, 15, and 20 mg/kg doses of resveratrol on the levels of ...

  12. 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